Add TuxOnIce support adapted for the 4.5-gnu kernel versionpck-4.5-gnu

97 files changed, 20917 insertions, 155 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 76d68c5df..a70383d0f 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -4059,6 +4059,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 					HIGHMEM regardless of setting
 					of CONFIG_HIGHPTE.
 
+	uuid_debug=	(Boolean) whether to enable debugging of TuxOnIce's
+			uuid support.
+
 	vdso=		[X86,SH]
 			On X86_32, this is an alias for vdso32=.  Otherwise:
 
diff --git a/Documentation/power/tuxonice-internals.txt b/Documentation/power/tuxonice-internals.txt
new file mode 100644
index 000000000..0c6a2163a
--- /dev/null
+++ b/Documentation/power/tuxonice-internals.txt
@@ -0,0 +1,532 @@
+		   TuxOnIce 4.0 Internal Documentation.
+			Updated to 23 March 2015
+
+(Please note that incremental image support mentioned in this document is work
+in progress. This document may need updating prior to the actual release of
+4.0!)
+
+1.  Introduction.
+
+    TuxOnIce 4.0 is an addition to the Linux Kernel, designed to
+    allow the user to quickly shutdown and quickly boot a computer, without
+    needing to close documents or programs. It is equivalent to the
+    hibernate facility in some laptops. This implementation, however,
+    requires no special BIOS or hardware support.
+
+    The code in these files is based upon the original implementation
+    prepared by Gabor Kuti and additional work by Pavel Machek and a
+    host of others. This code has been substantially reworked by Nigel
+    Cunningham, again with the help and testing of many others, not the
+    least of whom are Bernard Blackham and Michael Frank. At its heart,
+    however, the operation is essentially the same as Gabor's version.
+
+2.  Overview of operation.
+
+    The basic sequence of operations is as follows:
+
+	a. Quiesce all other activity.
+	b. Ensure enough memory and storage space are available, and attempt
+	   to free memory/storage if necessary.
+	c. Allocate the required memory and storage space.
+	d. Write the image.
+	e. Power down.
+
+    There are a number of complicating factors which mean that things are
+    not as simple as the above would imply, however...
+
+    o The activity of each process must be stopped at a point where it will
+    not be holding locks necessary for saving the image, or unexpectedly
+    restart operations due to something like a timeout and thereby make
+    our image inconsistent.
+
+    o It is desirous that we sync outstanding I/O to disk before calculating
+    image statistics. This reduces corruption if one should suspend but
+    then not resume, and also makes later parts of the operation safer (see
+    below).
+
+    o We need to get as close as we can to an atomic copy of the data.
+    Inconsistencies in the image will result in inconsistent memory contents at
+    resume time, and thus in instability of the system and/or file system
+    corruption. This would appear to imply a maximum image size of one half of
+    the amount of RAM, but we have a solution... (again, below).
+
+    o In 2.6 and later, we choose to play nicely with the other suspend-to-disk
+    implementations.
+
+3.  Detailed description of internals.
+
+    a. Quiescing activity.
+
+    Safely quiescing the system is achieved using three separate but related
+    aspects.
+
+    First, we use the vanilla kerne's support for freezing processes. This code
+    is based on the observation that the vast majority of processes don't need
+    to run during suspend. They can be 'frozen'. The kernel therefore
+    implements a refrigerator routine, which processes enter and in which they
+    remain until the cycle is complete. Processes enter the refrigerator via
+    try_to_freeze() invocations at appropriate places.  A process cannot be
+    frozen in any old place. It must not be holding locks that will be needed
+    for writing the image or freezing other processes. For this reason,
+    userspace processes generally enter the refrigerator via the signal
+    handling code, and kernel threads at the place in their event loops where
+    they drop locks and yield to other processes or sleep. The task of freezing
+    processes is complicated by the fact that there can be interdependencies
+    between processes. Freezing process A before process B may mean that
+    process B cannot be frozen, because it stops at waiting for process A
+    rather than in the refrigerator. This issue is seen where userspace waits
+    on freezeable kernel threads or fuse filesystem threads. To address this
+    issue, we implement the following algorithm for quiescing activity:
+
+	- Freeze filesystems (including fuse - userspace programs starting
+		new requests are immediately frozen; programs already running
+		requests complete their work before being frozen in the next
+		step)
+	- Freeze userspace
+	- Thaw filesystems (this is safe now that userspace is frozen and no
+		fuse requests are outstanding).
+	- Invoke sys_sync (noop on fuse).
+	- Freeze filesystems
+	- Freeze kernel threads
+
+    If we need to free memory, we thaw kernel threads and filesystems, but not
+    userspace. We can then free caches without worrying about deadlocks due to
+    swap files being on frozen filesystems or such like.
+
+    b. Ensure enough memory & storage are available.
+
+    We have a number of constraints to meet in order to be able to successfully
+    suspend and resume.
+
+    First, the image will be written in two parts, described below. One of
+    these parts needs to have an atomic copy made, which of course implies a
+    maximum size of one half of the amount of system memory. The other part
+    ('pageset') is not atomically copied, and can therefore be as large or
+    small as desired.
+
+    Second, we have constraints on the amount of storage available. In these
+    calculations, we may also consider any compression that will be done. The
+    cryptoapi module allows the user to configure an expected compression ratio.
+
+    Third, the user can specify an arbitrary limit on the image size, in
+    megabytes. This limit is treated as a soft limit, so that we don't fail the
+    attempt to suspend if we cannot meet this constraint.
+
+    c. Allocate the required memory and storage space.
+
+    Having done the initial freeze, we determine whether the above constraints
+    are met, and seek to allocate the metadata for the image. If the constraints
+    are not met, or we fail to allocate the required space for the metadata, we
+    seek to free the amount of memory that we calculate is needed and try again.
+    We allow up to four iterations of this loop before aborting the cycle. If
+    we do fail, it should only be because of a bug in TuxOnIce's calculations
+    or the vanilla kernel code for freeing memory.
+
+    These steps are merged together in the prepare_image function, found in
+    prepare_image.c. The functions are merged because of the cyclical nature
+    of the problem of calculating how much memory and storage is needed. Since
+    the data structures containing the information about the image must
+    themselves take memory and use storage, the amount of memory and storage
+    required changes as we prepare the image. Since the changes are not large,
+    only one or two iterations will be required to achieve a solution.
+
+    The recursive nature of the algorithm is miminised by keeping user space
+    frozen while preparing the image, and by the fact that our records of which
+    pages are to be saved and which pageset they are saved in use bitmaps (so
+    that changes in number or fragmentation of the pages to be saved don't
+    feedback via changes in the amount of memory needed for metadata). The
+    recursiveness is thus limited to any extra slab pages allocated to store the
+    extents that record storage used, and the effects of seeking to free memory.
+
+    d. Write the image.
+
+    We previously mentioned the need to create an atomic copy of the data, and
+    the half-of-memory limitation that is implied in this. This limitation is
+    circumvented by dividing the memory to be saved into two parts, called
+    pagesets.
+
+    Pageset2 contains most of the page cache - the pages on the active and
+    inactive LRU lists that aren't needed or modified while TuxOnIce is
+    running, so they can be safely written without an atomic copy. They are
+    therefore saved first and reloaded last. While saving these pages,
+    TuxOnIce carefully ensures that the work of writing the pages doesn't make
+    the image inconsistent. With the support for Kernel (Video) Mode Setting
+    going into the kernel at the time of writing, we need to check for pages
+    on the LRU that are used by KMS, and exclude them from pageset2. They are
+    atomically copied as part of pageset 1.
+
+    Once pageset2 has been saved, we prepare to do the atomic copy of remaining
+    memory. As part of the preparation, we power down drivers, thereby providing
+    them with the opportunity to have their state recorded in the image. The
+    amount of memory allocated by drivers for this is usually negligible, but if
+    DRI is in use, video drivers may require significants amounts. Ideally we
+    would be able to query drivers while preparing the image as to the amount of
+    memory they will need. Unfortunately no such mechanism exists at the time of
+    writing. For this reason, TuxOnIce allows the user to set an
+    'extra_pages_allowance', which is used to seek to ensure sufficient memory
+    is available for drivers at this point. TuxOnIce also lets the user set this
+    value to 0. In this case, a test driver suspend is done while preparing the
+    image, and the difference (plus a margin) used instead. TuxOnIce will also
+    automatically restart the hibernation process (twice at most) if it finds
+    that the extra pages allowance is not sufficient. It will then use what was
+    actually needed (plus a margin, again). Failure to hibernate should thus
+    be an extremely rare occurence.
+
+    Having suspended the drivers, we save the CPU context before making an
+    atomic copy of pageset1, resuming the drivers and saving the atomic copy.
+    After saving the two pagesets, we just need to save our metadata before
+    powering down.
+
+    As we mentioned earlier, the contents of pageset2 pages aren't needed once
+    they've been saved. We therefore use them as the destination of our atomic
+    copy. In the unlikely event that pageset1 is larger, extra pages are
+    allocated while the image is being prepared. This is normally only a real
+    possibility when the system has just been booted and the page cache is
+    small.
+
+    This is where we need to be careful about syncing, however. Pageset2 will
+    probably contain filesystem meta data. If this is overwritten with pageset1
+    and then a sync occurs, the filesystem will be corrupted - at least until
+    resume time and another sync of the restored data. Since there is a
+    possibility that the user might not resume or (may it never be!) that
+    TuxOnIce might oops, we do our utmost to avoid syncing filesystems after
+    copying pageset1.
+
+    e. Incremental images
+
+    TuxOnIce 4.0 introduces a new incremental image mode which changes things a
+    little. When incremental images are enabled, we save a 'normal' image the
+    first time we hibernate. One resume however, we do not free the image or
+    the associated storage. Instead, it is retained until the next attempt at
+    hibernating and a mechanism is enabled which is used to track which pages
+    of memory are modified between the two cycles. The modified pages can then
+    be added to the existing image, rather than unmodified pages being saved
+    again unnecessarily.
+
+    Incremental image support is available in 64 bit Linux only, due to the
+    requirement for extra page flags.
+
+    This support is accomplished in the following way:
+
+    1) Tracking of pages.
+
+    The tracking of changed pages is accomplished using the page fault
+    mechanism. When we reach a point at which we want to start tracking
+    changes, most pages are marked read-only and also flagged as being
+    read-only because of this support. Since this cannot happen for every page
+    of RAM, some are marked as untracked and always treated as modified whn
+    preparing an incremental iamge. When a process attempts to modify a page
+    that is marked read-only in this way, a page fault occurs, with TuxOnIce
+    code marking the page writable and dirty before allowing the write to
+    continue. In this way, the effect of incremental images on performance is
+    minimised - a page only causes a fault once. Small modifications to the
+    page allocator further reduce the number of faults that occur - free pages
+    are not tracked; they are made writable and marked as dirty as part of
+    being allocated.
+
+    2) Saving the incremental image / atomicity.
+
+    The page fault mechanism is also used to improve the means by which
+    atomicity of the image is acheived. When it is time to do an atomic copy,
+    the flags for pages are reset, with the result being that it is no longer
+    necessary for us to do an atomic of pageset1. Instead, we normally write
+    the uncopied pages to disk. When an attempt is made to modify a page that
+    has not yet been saved, the page-fault mechanism makes a copy of the page
+    prior to allowing the write. This copy is then written to disk. Likewise,
+    on resume, if a process attempts to write to a page that has been read
+    while the rest of the image is still being loaded, a copy of that page is
+    made prior to the write being allowed. At the end of loading the image,
+    modified pages can thus be restored to their 'atomic copy' contents prior
+    to restarting normal operation. We also mark pages that are yet to be read
+    as invalid PFNs, so that we can capture as a bug any attempt by a
+    half-restored kernel to access a page that hasn't yet been reloaded.
+
+    f. Power down.
+
+    Powering down uses standard kernel routines. TuxOnIce supports powering down
+    using the ACPI S3, S4 and S5 methods or the kernel's non-ACPI power-off.
+    Supporting suspend to ram (S3) as a power off option might sound strange,
+    but it allows the user to quickly get their system up and running again if
+    the battery doesn't run out (we just need to re-read the overwritten pages)
+    and if the battery does run out (or the user removes power), they can still
+    resume.
+
+4.  Data Structures.
+
+    TuxOnIce uses three main structures to store its metadata and configuration
+    information:
+
+    a) Pageflags bitmaps.
+
+    TuxOnIce records which pages will be in pageset1, pageset2, the destination
+    of the atomic copy and the source of the atomically restored image using
+    bitmaps. The code used is that written for swsusp, with small improvements
+    to match TuxOnIce's requirements.
+
+    The pageset1 bitmap is thus easily stored in the image header for use at
+    resume time.
+
+    As mentioned above, using bitmaps also means that the amount of memory and
+    storage required for recording the above information is constant. This
+    greatly simplifies the work of preparing the image. In earlier versions of
+    TuxOnIce, extents were used to record which pages would be stored. In that
+    case, however, eating memory could result in greater fragmentation of the
+    lists of pages, which in turn required more memory to store the extents and
+    more storage in the image header. These could in turn require further
+    freeing of memory, and another iteration. All of this complexity is removed
+    by having bitmaps.
+
+    Bitmaps also make a lot of sense because TuxOnIce only ever iterates
+    through the lists. There is therefore no cost to not being able to find the
+    nth page in order 0 time. We only need to worry about the cost of finding
+    the n+1th page, given the location of the nth page. Bitwise optimisations
+    help here.
+
+    b) Extents for block data.
+
+    TuxOnIce supports writing the image to multiple block devices. In the case
+    of swap, multiple partitions and/or files may be in use, and we happily use
+    them all (with the exception of compcache pages, which we allocate but do
+    not use). This use of multiple block devices is accomplished as follows:
+
+    Whatever the actual source of the allocated storage, the destination of the
+    image can be viewed in terms of one or more block devices, and on each
+    device, a list of sectors. To simplify matters, we only use contiguous,
+    PAGE_SIZE aligned sectors, like the swap code does.
+
+    Since sector numbers on each bdev may well not start at 0, it makes much
+    more sense to use extents here. Contiguous ranges of pages can thus be
+    represented in the extents by contiguous values.
+
+    Variations in block size are taken account of in transforming this data
+    into the parameters for bio submission.
+
+    We can thus implement a layer of abstraction wherein the core of TuxOnIce
+    doesn't have to worry about which device we're currently writing to or
+    where in the device we are. It simply requests that the next page in the
+    pageset or header be written, leaving the details to this lower layer.
+    The lower layer remembers where in the sequence of devices and blocks each
+    pageset starts. The header always starts at the beginning of the allocated
+    storage.
+
+    So extents are:
+
+    struct extent {
+      unsigned long minimum, maximum;
+      struct extent *next;
+    }
+
+    These are combined into chains of extents for a device:
+
+    struct extent_chain {
+      int size; /* size of the extent ie sum (max-min+1) */
+      int allocs, frees;
+      char *name;
+      struct extent *first, *last_touched;
+    };
+
+    For each bdev, we need to store a little more info (simplified definition):
+
+    struct toi_bdev_info {
+       struct block_device *bdev;
+
+       char uuid[17];
+       dev_t dev_t;
+       int bmap_shift;
+       int blocks_per_page;
+    };
+
+    The uuid is the main means used to identify the device in the storage
+    image. This means we can cope with the dev_t representation of a device
+    changing between saving the image and restoring it, as may happen on some
+    bioses or in the LVM case.
+
+    bmap_shift and blocks_per_page apply the effects of variations in blocks
+    per page settings for the filesystem and underlying bdev. For most
+    filesystems, these are the same, but for xfs, they can have independant
+    values.
+
+    Combining these two structures together, we have everything we need to
+    record what devices and what blocks on each device are being used to
+    store the image, and to submit i/o using bio_submit.
+
+    The last elements in the picture are a means of recording how the storage
+    is being used.
+
+    We do this first and foremost by implementing a layer of abstraction on
+    top of the devices and extent chains which allows us to view however many
+    devices there might be as one long storage tape, with a single 'head' that
+    tracks a 'current position' on the tape:
+
+    struct extent_iterate_state {
+      struct extent_chain *chains;
+      int num_chains;
+      int current_chain;
+      struct extent *current_extent;
+      unsigned long current_offset;
+    };
+
+    That is, *chains points to an array of size num_chains of extent chains.
+    For the filewriter, this is always a single chain. For the swapwriter, the
+    array is of size MAX_SWAPFILES.
+
+    current_chain, current_extent and current_offset thus point to the current
+    index in the chains array (and into a matching array of struct
+    suspend_bdev_info), the current extent in that chain (to optimise access),
+    and the current value in the offset.
+
+    The image is divided into three parts:
+    - The header
+    - Pageset 1
+    - Pageset 2
+
+    The header always starts at the first device and first block. We know its
+    size before we begin to save the image because we carefully account for
+    everything that will be stored in it.
+
+    The second pageset (LRU) is stored first. It begins on the next page after
+    the end of the header.
+
+    The first pageset is stored second. It's start location is only known once
+    pageset2 has been saved, since pageset2 may be compressed as it is written.
+    This location is thus recorded at the end of saving pageset2. It is page
+    aligned also.
+
+    Since this information is needed at resume time, and the location of extents
+    in memory will differ at resume time, this needs to be stored in a portable
+    way:
+
+    struct extent_iterate_saved_state {
+        int chain_num;
+        int extent_num;
+        unsigned long offset;
+    };
+
+    We can thus implement a layer of abstraction wherein the core of TuxOnIce
+    doesn't have to worry about which device we're currently writing to or
+    where in the device we are. It simply requests that the next page in the
+    pageset or header be written, leaving the details to this layer, and
+    invokes the routines to remember and restore the position, without having
+    to worry about the details of how the data is arranged on disk or such like.
+
+    c) Modules
+
+    One aim in designing TuxOnIce was to make it flexible. We wanted to allow
+    for the implementation of different methods of transforming a page to be
+    written to disk and different methods of getting the pages stored.
+
+    In early versions (the betas and perhaps Suspend1), compression support was
+    inlined in the image writing code, and the data structures and code for
+    managing swap were intertwined with the rest of the code. A number of people
+    had expressed interest in implementing image encryption, and alternative
+    methods of storing the image.
+
+    In order to achieve this, TuxOnIce was given a modular design.
+
+    A module is a single file which encapsulates the functionality needed
+    to transform a pageset of data (encryption or compression, for example),
+    or to write the pageset to a device. The former type of module is called
+    a 'page-transformer', the later a 'writer'.
+
+    Modules are linked together in pipeline fashion. There may be zero or more
+    page transformers in a pipeline, and there is always exactly one writer.
+    The pipeline follows this pattern:
+
+		---------------------------------
+		|          TuxOnIce Core        |
+		---------------------------------
+				|
+				|
+		---------------------------------
+		|	Page transformer 1	|
+		---------------------------------
+				|
+				|
+		---------------------------------
+		|	Page transformer 2	|
+		---------------------------------
+				|
+				|
+		---------------------------------
+		|            Writer		|
+		---------------------------------
+
+    During the writing of an image, the core code feeds pages one at a time
+    to the first module. This module performs whatever transformations it
+    implements on the incoming data, completely consuming the incoming data and
+    feeding output in a similar manner to the next module.
+
+    All routines are SMP safe, and the final result of the transformations is
+    written with an index (provided by the core) and size of the output by the
+    writer. As a result, we can have multithreaded I/O without needing to
+    worry about the sequence in which pages are written (or read).
+
+    During reading, the pipeline works in the reverse direction. The core code
+    calls the first module with the address of a buffer which should be filled.
+    (Note that the buffer size is always PAGE_SIZE at this time). This module
+    will in turn request data from the next module and so on down until the
+    writer is made to read from the stored image.
+
+    Part of definition of the structure of a module thus looks like this:
+
+        int (*rw_init) (int rw, int stream_number);
+        int (*rw_cleanup) (int rw);
+        int (*write_chunk) (struct page *buffer_page);
+        int (*read_chunk) (struct page *buffer_page, int sync);
+
+    It should be noted that the _cleanup routine may be called before the
+    full stream of data has been read or written. While writing the image,
+    the user may (depending upon settings) choose to abort suspending, and
+    if we are in the midst of writing the last portion of the image, a portion
+    of the second pageset may be reread. This may also happen if an error
+    occurs and we seek to abort the process of writing the image.
+
+    The modular design is also useful in a number of other ways. It provides
+    a means where by we can add support for:
+
+    - providing overall initialisation and cleanup routines;
+    - serialising configuration information in the image header;
+    - providing debugging information to the user;
+    - determining memory and image storage requirements;
+    - dis/enabling components at run-time;
+    - configuring the module (see below);
+
+    ...and routines for writers specific to their work:
+    - Parsing a resume= location;
+    - Determining whether an image exists;
+    - Marking a resume as having been attempted;
+    - Invalidating an image;
+
+    Since some parts of the core - the user interface and storage manager
+    support - have use for some of these functions, they are registered as
+    'miscellaneous' modules as well.
+
+    d) Sysfs data structures.
+
+    This brings us naturally to support for configuring TuxOnIce. We desired to
+    provide a way to make TuxOnIce as flexible and configurable as possible.
+    The user shouldn't have to reboot just because they want to now hibernate to
+    a file instead of a partition, for example.
+
+    To accomplish this, TuxOnIce implements a very generic means whereby the
+    core and modules can register new sysfs entries. All TuxOnIce entries use
+    a single _store and _show routine, both of which are found in
+    tuxonice_sysfs.c in the kernel/power directory. These routines handle the
+    most common operations - getting and setting the values of bits, integers,
+    longs, unsigned longs and strings in one place, and allow overrides for
+    customised get and set options as well as side-effect routines for all
+    reads and writes.
+
+    When combined with some simple macros, a new sysfs entry can then be defined
+    in just a couple of lines:
+
+        SYSFS_INT("progress_granularity", SYSFS_RW, &progress_granularity, 1,
+                        2048, 0, NULL),
+
+    This defines a sysfs entry named "progress_granularity" which is rw and
+    allows the user to access an integer stored at &progress_granularity, giving
+    it a value between 1 and 2048 inclusive.
+
+    Sysfs entries are registered under /sys/power/tuxonice, and entries for
+    modules are located in a subdirectory named after the module.
+
diff --git a/Documentation/power/tuxonice.txt b/Documentation/power/tuxonice.txt
new file mode 100644
index 000000000..3bf0575ef
--- /dev/null
+++ b/Documentation/power/tuxonice.txt
@@ -0,0 +1,948 @@
+	--- TuxOnIce, version 3.0 ---
+
+1.  What is it?
+2.  Why would you want it?
+3.  What do you need to use it?
+4.  Why not just use the version already in the kernel?
+5.  How do you use it?
+6.  What do all those entries in /sys/power/tuxonice do?
+7.  How do you get support?
+8.  I think I've found a bug. What should I do?
+9.  When will XXX be supported?
+10  How does it work?
+11. Who wrote TuxOnIce?
+
+1. What is it?
+
+   Imagine you're sitting at your computer, working away. For some reason, you
+   need to turn off your computer for a while - perhaps it's time to go home
+   for the day. When you come back to your computer next, you're going to want
+   to carry on where you left off. Now imagine that you could push a button and
+   have your computer store the contents of its memory to disk and power down.
+   Then, when you next start up your computer, it loads that image back into
+   memory and you can carry on from where you were, just as if you'd never
+   turned the computer off. You have far less time to start up, no reopening of
+   applications or finding what directory you put that file in yesterday.
+   That's what TuxOnIce does.
+
+   TuxOnIce has a long heritage. It began life as work by Gabor Kuti, who,
+   with some help from Pavel Machek, got an early version going in 1999. The
+   project was then taken over by Florent Chabaud while still in alpha version
+   numbers. Nigel Cunningham came on the scene when Florent was unable to
+   continue, moving the project into betas, then 1.0, 2.0 and so on up to
+   the present series. During the 2.0 series, the name was contracted to
+   Suspend2 and the website suspend2.net created. Beginning around July 2007,
+   a transition to calling the software TuxOnIce was made, to seek to help
+   make it clear that TuxOnIce is more concerned with hibernation than suspend
+   to ram.
+
+   Pavel Machek's swsusp code, which was merged around 2.5.17 retains the
+   original name, and was essentially a fork of the beta code until Rafael
+   Wysocki came on the scene in 2005 and began to improve it further.
+
+2. Why would you want it?
+
+   Why wouldn't you want it?
+
+   Being able to save the state of your system and quickly restore it improves
+   your productivity - you get a useful system in far less time than through
+   the normal boot process. You also get to be completely 'green', using zero
+   power, or as close to that as possible (the computer may still provide
+   minimal power to some devices, so they can initiate a power on, but that
+   will be the same amount of power as would be used if you told the computer
+   to shutdown.
+
+3. What do you need to use it?
+
+   a. Kernel Support.
+
+   i) The TuxOnIce patch.
+
+   TuxOnIce is part of the Linux Kernel. This version is not part of Linus's
+   2.6 tree at the moment, so you will need to download the kernel source and
+   apply the latest patch. Having done that, enable the appropriate options in
+   make [menu|x]config (under Power Management Options - look for "Enhanced
+   Hibernation"), compile and install your kernel. TuxOnIce works with SMP,
+   Highmem, preemption, fuse filesystems, x86-32, PPC and x86_64.
+
+   TuxOnIce patches are available from http://tuxonice.net.
+
+   ii) Compression support.
+
+   Compression support is implemented via the cryptoapi. You will therefore want
+   to select any Cryptoapi transforms that you want to use on your image from
+   the Cryptoapi menu while configuring your kernel. We recommend the use of the
+   LZO compression method - it is very fast and still achieves good compression.
+
+   You can also tell TuxOnIce to write its image to an encrypted and/or
+   compressed filesystem/swap partition. In that case, you don't need to do
+   anything special for TuxOnIce when it comes to kernel configuration.
+
+   iii) Configuring other options.
+
+   While you're configuring your kernel, try to configure as much as possible
+   to build as modules. We recommend this because there are a number of drivers
+   that are still in the process of implementing proper power management
+   support. In those cases, the best way to work around their current lack is
+   to build them as modules and remove the modules while hibernating. You might
+   also bug the driver authors to get their support up to speed, or even help!
+
+   b. Storage.
+
+   i) Swap.
+
+   TuxOnIce can store the hibernation image in your swap partition, a swap file or
+   a combination thereof. Whichever combination you choose, you will probably
+   want to create enough swap space to store the largest image you could have,
+   plus the space you'd normally use for swap. A good rule of thumb would be
+   to calculate the amount of swap you'd want without using TuxOnIce, and then
+   add the amount of memory you have. This swapspace can be arranged in any way
+   you'd like. It can be in one partition or file, or spread over a number. The
+   only requirement is that they be active when you start a hibernation cycle.
+
+   There is one exception to this requirement. TuxOnIce has the ability to turn
+   on one swap file or partition at the start of hibernating and turn it back off
+   at the end. If you want to ensure you have enough memory to store a image
+   when your memory is fully used, you might want to make one swap partition or
+   file for 'normal' use, and another for TuxOnIce to activate & deactivate
+   automatically. (Further details below).
+
+   ii) Normal files.
+
+   TuxOnIce includes a 'file allocator'. The file allocator can store your
+   image in a simple file. Since Linux has the concept of everything being a
+   file, this is more powerful than it initially sounds. If, for example, you
+   were to set up a network block device file, you could hibernate to a network
+   server. This has been tested and works to a point, but nbd itself isn't
+   stateless enough for our purposes.
+
+   Take extra care when setting up the file allocator. If you just type
+   commands without thinking and then try to hibernate, you could cause
+   irreversible corruption on your filesystems! Make sure you have backups.
+
+   Most people will only want to hibernate to a local file. To achieve that, do
+   something along the lines of:
+
+   echo "TuxOnIce" > /hibernation-file
+   dd if=/dev/zero bs=1M count=512 >> /hibernation-file
+
+   This will create a 512MB file called /hibernation-file. To get TuxOnIce to use
+   it:
+
+   echo /hibernation-file > /sys/power/tuxonice/file/target
+
+   Then
+
+   cat /sys/power/tuxonice/resume
+
+   Put the results of this into your bootloader's configuration (see also step
+   C, below):
+
+   ---EXAMPLE-ONLY-DON'T-COPY-AND-PASTE---
+   # cat /sys/power/tuxonice/resume
+   file:/dev/hda2:0x1e001
+
+   In this example, we would edit the append= line of our lilo.conf|menu.lst
+   so that it included:
+
+   resume=file:/dev/hda2:0x1e001
+   ---EXAMPLE-ONLY-DON'T-COPY-AND-PASTE---
+
+   For those who are thinking 'Could I make the file sparse?', the answer is
+   'No!'. At the moment, there is no way for TuxOnIce to fill in the holes in
+   a sparse file while hibernating. In the longer term (post merge!), I'd like
+   to change things so that the file could be dynamically resized and have
+   holes filled as needed. Right now, however, that's not possible and not a
+   priority.
+
+   c. Bootloader configuration.
+
+   Using TuxOnIce also requires that you add an extra parameter to
+   your lilo.conf or equivalent. Here's an example for a swap partition:
+
+   append="resume=swap:/dev/hda1"
+
+   This would tell TuxOnIce that /dev/hda1 is a swap partition you
+   have. TuxOnIce will use the swap signature of this partition as a
+   pointer to your data when you hibernate. This means that (in this example)
+   /dev/hda1 doesn't need to be _the_ swap partition where all of your data
+   is actually stored. It just needs to be a swap partition that has a
+   valid signature.
+
+   You don't need to have a swap partition for this purpose. TuxOnIce
+   can also use a swap file, but usage is a little more complex. Having made
+   your swap file, turn it on and do
+
+   cat /sys/power/tuxonice/swap/headerlocations
+
+   (this assumes you've already compiled your kernel with TuxOnIce
+   support and booted it). The results of the cat command will tell you
+   what you need to put in lilo.conf:
+
+   For swap partitions like /dev/hda1, simply use resume=/dev/hda1.
+   For swapfile `swapfile`, use resume=swap:/dev/hda2:0x242d.
+
+   If the swapfile changes for any reason (it is moved to a different
+   location, it is deleted and recreated, or the filesystem is
+   defragmented) then you will have to check
+   /sys/power/tuxonice/swap/headerlocations for a new resume_block value.
+
+   Once you've compiled and installed the kernel and adjusted your bootloader
+   configuration, you should only need to reboot for the most basic part
+   of TuxOnIce to be ready.
+
+   If you only compile in the swap allocator, or only compile in the file
+   allocator, you don't need to add the "swap:" part of the resume=
+   parameters above. resume=/dev/hda2:0x242d will work just as well. If you
+   have compiled both and your storage is on swap, you can also use this
+   format (the swap allocator is the default allocator).
+
+   When compiling your kernel, one of the options in the 'Power Management
+   Support' menu, just above the 'Enhanced Hibernation (TuxOnIce)' entry is
+   called 'Default resume partition'. This can be used to set a default value
+   for the resume= parameter.
+
+   d. The hibernate script.
+
+   Since the driver model in 2.6 kernels is still being developed, you may need
+   to do more than just configure TuxOnIce. Users of TuxOnIce usually start the
+   process via a script which prepares for the hibernation cycle, tells the
+   kernel to do its stuff and then restore things afterwards. This script might
+   involve:
+
+   - Switching to a text console and back if X doesn't like the video card
+     status on resume.
+   - Un/reloading drivers that don't play well with hibernation.
+
+   Note that you might not be able to unload some drivers if there are
+   processes using them. You might have to kill off processes that hold
+   devices open. Hint: if your X server accesses an USB mouse, doing a
+   'chvt' to a text console releases the device and you can unload the
+   module.
+
+   Check out the latest script (available on tuxonice.net).
+
+   e. The userspace user interface.
+
+   TuxOnIce has very limited support for displaying status if you only apply
+   the kernel patch - it can printk messages, but that is all. In addition,
+   some of the functions mentioned in this document (such as cancelling a cycle
+   or performing interactive debugging) are unavailable. To utilise these
+   functions, or simply get a nice display, you need the 'userui' component.
+   Userui comes in three flavours, usplash, fbsplash and text. Text should
+   work on any console. Usplash and fbsplash require the appropriate
+   (distro specific?) support.
+
+   To utilise a userui, TuxOnIce just needs to be told where to find the
+   userspace binary:
+
+   echo "/usr/local/sbin/tuxoniceui_fbsplash" > /sys/power/tuxonice/user_interface/program
+
+   The hibernate script can do this for you, and a default value for this
+   setting can be configured when compiling the kernel. This path is also
+   stored in the image header, so if you have an initrd or initramfs, you can
+   use the userui during the first part of resuming (prior to the atomic
+   restore) by putting the binary in the same path in your initrd/ramfs.
+   Alternatively, you can put it in a different location and do an echo
+   similar to the above prior to the echo > do_resume. The value saved in the
+   image header will then be ignored.
+
+4. Why not just use the version already in the kernel?
+
+   The version in the vanilla kernel has a number of drawbacks. The most
+   serious of these are:
+	- it has a maximum image size of 1/2 total memory;
+	- it doesn't allocate storage until after it has snapshotted memory.
+	  This means that you can't be sure hibernating will work until you
+	  see it start to write the image;
+	- it does not allow you to press escape to cancel a cycle;
+	- it does not allow you to press escape to cancel resuming;
+	- it does not allow you to automatically swapon a file when
+	  starting a cycle;
+	- it does not allow you to use multiple swap partitions or files;
+	- it does not allow you to use ordinary files;
+	- it just invalidates an image and continues to boot if you
+	  accidentally boot the wrong kernel after hibernating;
+	- it doesn't support any sort of nice display while hibernating;
+	- it is moving toward requiring that you have an initrd/initramfs
+	  to ever have a hope of resuming (uswsusp). While uswsusp will
+	  address some of the concerns above, it won't address all of them,
+          and will be more complicated to get set up;
+        - it doesn't have support for suspend-to-both (write a hibernation
+	  image, then suspend to ram; I think this is known as ReadySafe
+	  under M$).
+
+5. How do you use it?
+
+   A hibernation cycle can be started directly by doing:
+
+	echo > /sys/power/tuxonice/do_hibernate
+
+   In practice, though, you'll probably want to use the hibernate script
+   to unload modules, configure the kernel the way you like it and so on.
+   In that case, you'd do (as root):
+
+	hibernate
+
+   See the hibernate script's man page for more details on the options it
+   takes.
+
+   If you're using the text or splash user interface modules, one feature of
+   TuxOnIce that you might find useful is that you can press Escape at any time
+   during hibernating, and the process will be aborted.
+
+   Due to the way hibernation works, this means you'll have your system back and
+   perfectly usable almost instantly. The only exception is when it's at the
+   very end of writing the image. Then it will need to reload a small (usually
+   4-50MBs, depending upon the image characteristics) portion first.
+
+   Likewise, when resuming, you can press escape and resuming will be aborted.
+   The computer will then powerdown again according to settings at that time for
+   the powerdown method or rebooting.
+
+   You can change the settings for powering down while the image is being
+   written by pressing 'R' to toggle rebooting and 'O' to toggle between
+   suspending to ram and powering down completely).
+
+   If you run into problems with resuming, adding the "noresume" option to
+   the kernel command line will let you skip the resume step and recover your
+   system. This option shouldn't normally be needed, because TuxOnIce modifies
+   the image header prior to the atomic restore, and will thus prompt you
+   if it detects that you've tried to resume an image before (this flag is
+   removed if you press Escape to cancel a resume, so you won't be prompted
+   then).
+
+   Recent kernels (2.6.24 onwards) add support for resuming from a different
+   kernel to the one that was hibernated (thanks to Rafael for his work on
+   this - I've just embraced and enhanced the support for TuxOnIce). This
+   should further reduce the need for you to use the noresume option.
+
+6. What do all those entries in /sys/power/tuxonice do?
+
+   /sys/power/tuxonice is the directory which contains files you can use to
+   tune and configure TuxOnIce to your liking. The exact contents of
+   the directory will depend upon the version of TuxOnIce you're
+   running and the options you selected at compile time. In the following
+   descriptions, names in brackets refer to compile time options.
+   (Note that they're all dependant upon you having selected CONFIG_TUXONICE
+   in the first place!).
+
+   Since the values of these settings can open potential security risks, the
+   writeable ones are accessible only to the root user. You may want to
+   configure sudo to allow you to invoke your hibernate script as an ordinary
+   user.
+
+   - alloc/failure_test
+
+   This debugging option provides a way of testing TuxOnIce's handling of
+   memory allocation failures. Each allocation type that TuxOnIce makes has
+   been given a unique number (see the source code). Echo the appropriate
+   number into this entry, and when TuxOnIce attempts to do that allocation,
+   it will pretend there was a failure and act accordingly.
+
+   - alloc/find_max_mem_allocated
+
+   This debugging option will cause TuxOnIce to find the maximum amount of
+   memory it used during a cycle, and report that information in debugging
+   information at the end of the cycle.
+
+   - alt_resume_param
+
+   Instead of powering down after writing a hibernation image, TuxOnIce
+   supports resuming from a different image. This entry lets you set the
+   location of the signature for that image (the resume= value you'd use
+   for it). Using an alternate image and keep_image mode, you can do things
+   like using an alternate image to power down an uninterruptible power
+   supply.
+
+   - block_io/target_outstanding_io
+
+   This value controls the amount of memory that the block I/O code says it
+   needs when the core code is calculating how much memory is needed for
+   hibernating and for resuming. It doesn't directly control the amount of
+   I/O that is submitted at any one time - that depends on the amount of
+   available memory (we may have more available than we asked for), the
+   throughput that is being achieved and the ability of the CPU to keep up
+   with disk throughput (particularly where we're compressing pages).
+
+   - checksum/enabled
+
+   Use cryptoapi hashing routines to verify that Pageset2 pages don't change
+   while we're saving the first part of the image, and to get any pages that
+   do change resaved in the atomic copy. This should normally not be needed,
+   but if you're seeing issues, please enable this. If your issues stop you
+   being able to resume, enable this option, hibernate and cancel the cycle
+   after the atomic copy is done. If the debugging info shows a non-zero
+   number of pages resaved, please report this to Nigel.
+
+   - compression/algorithm
+
+   Set the cryptoapi algorithm used for compressing the image.
+
+   - compression/expected_compression
+
+   These values allow you to set an expected compression ratio, which TuxOnice
+   will use in calculating whether it meets constraints on the image size. If
+   this expected compression ratio is not attained, the hibernation cycle will
+   abort, so it is wise to allow some spare. You can see what compression
+   ratio is achieved in the logs after hibernating.
+
+   - debug_info:
+
+   This file returns information about your configuration that may be helpful
+   in diagnosing problems with hibernating.
+
+   - did_suspend_to_both:
+
+   This file can be used when you hibernate with powerdown method 3 (ie suspend
+   to ram after writing the image). There can be two outcomes in this case. We
+   can resume from the suspend-to-ram before the battery runs out, or we can run
+   out of juice and and up resuming like normal. This entry lets you find out,
+   post resume, which way we went. If the value is 1, we resumed from suspend
+   to ram. This can be useful when actions need to be run post suspend-to-ram
+   that don't need to be run if we did the normal resume from power off.
+
+   - do_hibernate:
+
+   When anything is written to this file, the kernel side of TuxOnIce will
+   begin to attempt to write an image to disk and power down. You'll normally
+   want to run the hibernate script instead, to get modules unloaded first.
+
+   - do_resume:
+
+   When anything is written to this file TuxOnIce will attempt to read and
+   restore an image. If there is no image, it will return almost immediately.
+   If an image exists, the echo > will never return. Instead, the original
+   kernel context will be restored and the original echo > do_hibernate will
+   return.
+
+   - */enabled
+
+   These option can be used to temporarily disable various parts of TuxOnIce.
+
+   - extra_pages_allowance
+
+   When TuxOnIce does its atomic copy, it calls the driver model suspend
+   and resume methods. If you have DRI enabled with a driver such as fglrx,
+   this can result in the driver allocating a substantial amount of memory
+   for storing its state. Extra_pages_allowance tells TuxOnIce how much
+   extra memory it should ensure is available for those allocations. If
+   your attempts at hibernating end with a message in dmesg indicating that
+   insufficient extra pages were allowed, you need to increase this value.
+
+   - file/target:
+
+   Read this value to get the current setting. Write to it to point TuxOnice
+   at a new storage location for the file allocator. See section 3.b.ii above
+   for details of how to set up the file allocator.
+
+   - freezer_test
+
+   This entry can be used to get TuxOnIce to just test the freezer and prepare
+   an image without actually doing a hibernation cycle. It is useful for
+   diagnosing freezing and image preparation issues.
+
+   - full_pageset2
+
+   TuxOnIce divides the pages that are stored in an image into two sets. The
+   difference between the two sets is that pages in pageset 1 are atomically
+   copied, and pages in pageset 2 are written to disk without being copied
+   first. A page CAN be written to disk without being copied first if and only
+   if its contents will not be modified or used at any time after userspace
+   processes are frozen. A page MUST be in pageset 1 if its contents are
+   modified or used at any time after userspace processes have been frozen.
+
+   Normally (ie if this option is enabled), TuxOnIce will put all pages on the
+   per-zone LRUs in pageset2, then remove those pages used by any userspace
+   user interface helper and TuxOnIce storage manager that are running,
+   together with pages used by the GEM memory manager introduced around 2.6.28
+   kernels.
+
+   If this option is disabled, a much more conservative approach will be taken.
+   The only pages in pageset2 will be those belonging to userspace processes,
+   with the exclusion of those belonging to the TuxOnIce userspace helpers
+   mentioned above. This will result in a much smaller pageset2, and will
+   therefore result in smaller images than are possible with this option
+   enabled.
+
+   - ignore_rootfs
+
+   TuxOnIce records which device is mounted as the root filesystem when
+   writing the hibernation image. It will normally check at resume time that
+   this device isn't already mounted - that would be a cause of filesystem
+   corruption. In some particular cases (RAM based root filesystems), you
+   might want to disable this check. This option allows you to do that.
+
+   - image_exists:
+
+   Can be used in a script to determine whether a valid image exists at the
+   location currently pointed to by resume=. Returns up to three lines.
+   The first is whether an image exists (-1 for unsure, otherwise 0 or 1).
+   If an image eixsts, additional lines will return the machine and version.
+   Echoing anything to this entry removes any current image.
+
+   - image_size_limit:
+
+   The maximum size of hibernation image written to disk, measured in megabytes
+   (1024*1024).
+
+   - last_result:
+
+   The result of the last hibernation cycle, as defined in
+   include/linux/suspend-debug.h with the values SUSPEND_ABORTED to
+   SUSPEND_KEPT_IMAGE. This is a bitmask.
+
+   - late_cpu_hotplug:
+
+   This sysfs entry controls whether cpu hotplugging is done - as normal - just
+   before (unplug) and after (replug) the atomic copy/restore (so that all
+   CPUs/cores are available for multithreaded I/O). The alternative is to
+   unplug all secondary CPUs/cores at the start of hibernating/resuming, and
+   replug them at the end of resuming. No multithreaded I/O will be possible in
+   this configuration, but the odd machine has been reported to require it.
+
+   - lid_file:
+
+   This determines which ACPI button file we look in to determine whether the
+   lid is open or closed after resuming from suspend to disk or power off.
+   If the entry is set to "lid/LID", we'll open /proc/acpi/button/lid/LID/state
+   and check its contents at the appropriate moment. See post_wake_state below
+   for more details on how this entry is used.
+
+   - log_everything (CONFIG_PM_DEBUG):
+
+   Setting this option results in all messages printed being logged. Normally,
+   only a subset are logged, so as to not slow the process and not clutter the
+   logs. Useful for debugging. It can be toggled during a cycle by pressing
+   'L'.
+
+   - no_load_direct:
+
+   This is a debugging option. If, when loading the atomically copied pages of
+   an image, TuxOnIce finds that the destination address for a page is free,
+   it will normally allocate the image, load the data directly into that
+   address and skip it in the atomic restore. If this option is disabled, the
+   page will be loaded somewhere else and atomically restored like other pages.
+
+   - no_flusher_thread:
+
+   When doing multithreaded I/O (see below), the first online CPU can be used
+   to _just_ submit compressed pages when writing the image, rather than
+   compressing and submitting data. This option is normally disabled, but has
+   been included because Nigel would like to see whether it will be more useful
+   as the number of cores/cpus in computers increases.
+
+   - no_multithreaded_io:
+
+   TuxOnIce will normally create one thread per cpu/core on your computer,
+   each of which will then perform I/O. This will generally result in
+   throughput that's the maximum the storage medium can handle. There
+   shouldn't be any reason to disable multithreaded I/O now, but this option
+   has been retained for debugging purposes.
+
+   - no_pageset2
+
+   See the entry for full_pageset2 above for an explanation of pagesets.
+   Enabling this option causes TuxOnIce to do an atomic copy of all pages,
+   thereby limiting the maximum image size to 1/2 of memory, as swsusp does.
+
+   - no_pageset2_if_unneeded
+
+   See the entry for full_pageset2 above for an explanation of pagesets.
+   Enabling this option causes TuxOnIce to act like no_pageset2 was enabled
+   if and only it isn't needed anyway. This option may still make TuxOnIce
+   less reliable because pageset2 pages are normally used to store the
+   atomic copy - drivers that want to do allocations of larger amounts of
+   memory in one shot will be more likely to find that those amounts aren't
+   available if this option is enabled.
+
+   - pause_between_steps (CONFIG_PM_DEBUG):
+
+   This option is used during debugging, to make TuxOnIce pause between
+   each step of the process. It is ignored when the nice display is on.
+
+   - post_wake_state:
+
+   TuxOnIce provides support for automatically waking after a user-selected
+   delay, and using a different powerdown method if the lid is still closed.
+   (Yes, we're assuming a laptop).  This entry lets you choose what state
+   should be entered next. The values are those described under
+   powerdown_method, below. It can be used to suspend to RAM after hibernating,
+   then powerdown properly (say) 20 minutes. It can also be used to power down
+   properly, then wake at (say) 6.30am and suspend to RAM until you're ready
+   to use the machine.
+
+   - powerdown_method:
+
+   Used to select a method by which TuxOnIce should powerdown after writing the
+   image. Currently:
+
+   0: Don't use ACPI to power off.
+   3: Attempt to enter Suspend-to-ram.
+   4: Attempt to enter ACPI S4 mode.
+   5: Attempt to power down via ACPI S5 mode.
+
+   Note that these options are highly dependant upon your hardware & software:
+
+   3: When succesful, your machine suspends to ram instead of powering off.
+      The advantage of using this mode is that it doesn't matter whether your
+      battery has enough charge to make it through to your next resume. If it
+      lasts, you will simply resume from suspend to ram (and the image on disk
+      will be discarded). If the battery runs out, you will resume from disk
+      instead. The disadvantage is that it takes longer than a normal
+      suspend-to-ram to enter the state, since the suspend-to-disk image needs
+      to be written first.
+   4/5: When successful, your machine will be off and comsume (almost) no power.
+      But it might still react to some external events like opening the lid or
+      trafic on  a network or usb device. For the bios, resume is then the same
+      as warm boot, similar to a situation where you used the command `reboot'
+      to reboot your machine. If your machine has problems on warm boot or if
+      you want to protect your machine with the bios password, this is probably
+      not the right choice. Mode 4 may be necessary on some machines where ACPI
+      wake up methods need to be run to properly reinitialise hardware after a
+      hibernation cycle.
+   0: Switch the machine completely off. The only possible wakeup is the power
+      button. For the bios, resume is then the same as a cold boot, in
+      particular you would  have to provide your bios boot password if your
+      machine uses that feature for booting.
+
+   - progressbar_granularity_limit:
+
+   This option can be used to limit the granularity of the progress bar
+   displayed with a bootsplash screen. The value is the maximum number of
+   steps. That is, 10 will make the progress bar jump in 10% increments.
+
+   - reboot:
+
+   This option causes TuxOnIce to reboot rather than powering down
+   at the end of saving an image. It can be toggled during a cycle by pressing
+   'R'.
+
+   - resume:
+
+   This sysfs entry can be used to read and set the location in which TuxOnIce
+   will look for the signature of an image - the value set using resume= at
+   boot time or CONFIG_PM_STD_PARTITION ("Default resume partition"). By
+   writing to this file as well as modifying your bootloader's configuration
+   file (eg menu.lst), you can set or reset the location of your image or the
+   method of storing the image without rebooting.
+
+   - replace_swsusp (CONFIG_TOI_REPLACE_SWSUSP):
+
+   This option makes
+
+     echo disk > /sys/power/state
+
+   activate TuxOnIce instead of swsusp. Regardless of whether this option is
+   enabled, any invocation of swsusp's resume time trigger will cause TuxOnIce
+   to check for an image too. This is due to the fact that at resume time, we
+   can't know whether this option was enabled until we see if an image is there
+   for us to resume from. (And when an image exists, we don't care whether we
+   did replace swsusp anyway - we just want to resume).
+
+   - resume_commandline:
+
+   This entry can be read after resuming to see the commandline that was used
+   when resuming began. You might use this to set up two bootloader entries
+   that are the same apart from the fact that one includes a extra append=
+   argument "at_work=1". You could then grep resume_commandline in your
+   post-resume scripts and configure networking (for example) differently
+   depending upon whether you're at home or work. resume_commandline can be
+   set to arbitrary text if you wish to remove sensitive contents.
+
+   - swap/swapfilename:
+
+   This entry is used to specify the swapfile or partition that
+   TuxOnIce will attempt to swapon/swapoff automatically. Thus, if
+   I normally use /dev/hda1 for swap, and want to use /dev/hda2 for specifically
+   for my hibernation image, I would
+
+   echo /dev/hda2 > /sys/power/tuxonice/swap/swapfile
+
+   /dev/hda2 would then be automatically swapon'd and swapoff'd. Note that the
+   swapon and swapoff occur while other processes are frozen (including kswapd)
+   so this swap file will not be used up when attempting to free memory. The
+   parition/file is also given the highest priority, so other swapfiles/partitions
+   will only be used to save the image when this one is filled.
+
+   The value of this file is used by headerlocations along with any currently
+   activated swapfiles/partitions.
+
+   - swap/headerlocations:
+
+   This option tells you the resume= options to use for swap devices you
+   currently have activated. It is particularly useful when you only want to
+   use a swap file to store your image. See above for further details.
+
+   - test_bio
+
+   This is a debugging option. When enabled, TuxOnIce will not hibernate.
+   Instead, when asked to write an image, it will skip the atomic copy,
+   just doing the writing of the image and then returning control to the
+   user at the point where it would have powered off. This is useful for
+   testing throughput in different configurations.
+
+   - test_filter_speed
+
+   This is a debugging option. When enabled, TuxOnIce will not hibernate.
+   Instead, when asked to write an image, it will not write anything or do
+   an atomic copy, but will only run any enabled compression algorithm on the
+   data that would have been written (the source pages of the atomic copy in
+   the case of pageset 1). This is useful for comparing the performance of
+   compression algorithms and for determining the extent to which an upgrade
+   to your storage method would improve hibernation speed.
+
+   - user_interface/debug_sections (CONFIG_PM_DEBUG):
+
+   This value, together with the console log level, controls what debugging
+   information is displayed. The console log level determines the level of
+   detail, and this value determines what detail is displayed. This value is
+   a bit vector, and the meaning of the bits can be found in the kernel tree
+   in include/linux/tuxonice.h. It can be overridden using the kernel's
+   command line option suspend_dbg.
+
+   - user_interface/default_console_level (CONFIG_PM_DEBUG):
+
+   This determines the value of the console log level at the start of a
+   hibernation cycle. If debugging is compiled in, the console log level can be
+   changed during a cycle by pressing the digit keys. Meanings are:
+
+   0: Nice display.
+   1: Nice display plus numerical progress.
+   2: Errors only.
+   3: Low level debugging info.
+   4: Medium level debugging info.
+   5: High level debugging info.
+   6: Verbose debugging info.
+
+   - user_interface/enable_escape:
+
+   Setting this to "1" will enable you abort a hibernation cycle or resuming by
+   pressing escape, "0" (default) disables this feature. Note that enabling
+   this option means that you cannot initiate a hibernation cycle and then walk
+   away from your computer, expecting it to be secure. With feature disabled,
+   you can validly have this expectation once TuxOnice begins to write the
+   image to disk. (Prior to this point, it is possible that TuxOnice might
+   about because of failure to freeze all processes or because constraints
+   on its ability to save the image are not met).
+
+   - user_interface/program
+
+   This entry is used to tell TuxOnice what userspace program to use for
+   providing a user interface while hibernating. The program uses a netlink
+   socket to pass messages back and forward to the kernel, allowing all of the
+   functions formerly implemented in the kernel user interface components.
+
+   - version:
+
+   The version of TuxOnIce you have compiled into the currently running kernel.
+
+   - wake_alarm_dir:
+
+   As mentioned above (post_wake_state), TuxOnIce supports automatically waking
+   after some delay. This entry allows you to select which wake alarm to use.
+   It should contain the value "rtc0" if you're wanting to use
+   /sys/class/rtc/rtc0.
+
+   - wake_delay:
+
+   This value determines the delay from the end of writing the image until the
+   wake alarm is triggered. You can set an absolute time by writing the desired
+   time into /sys/class/rtc/<wake_alarm_dir>/wakealarm and leaving these values
+   empty.
+
+   Note that for the wakeup to actually occur, you may need to modify entries
+   in /proc/acpi/wakeup. This is done by echoing the name of the button in the
+   first column (eg PBTN) into the file.
+
+7. How do you get support?
+
+   Glad you asked. TuxOnIce is being actively maintained and supported
+   by Nigel (the guy doing most of the kernel coding at the moment), Bernard
+   (who maintains the hibernate script and userspace user interface components)
+   and its users.
+
+   Resources availble include HowTos, FAQs and a Wiki, all available via
+   tuxonice.net.  You can find the mailing lists there.
+
+8. I think I've found a bug. What should I do?
+
+   By far and a way, the most common problems people have with TuxOnIce
+   related to drivers not having adequate power management support. In this
+   case, it is not a bug with TuxOnIce, but we can still help you. As we
+   mentioned above, such issues can usually be worked around by building the
+   functionality as modules and unloading them while hibernating. Please visit
+   the Wiki for up-to-date lists of known issues and work arounds.
+
+   If this information doesn't help, try running:
+
+   hibernate --bug-report
+
+   ..and sending the output to the users mailing list.
+
+   Good information on how to provide us with useful information from an
+   oops is found in the file REPORTING-BUGS, in the top level directory
+   of the kernel tree. If you get an oops, please especially note the
+   information about running what is printed on the screen through ksymoops.
+   The raw information is useless.
+
+9. When will XXX be supported?
+
+   If there's a feature missing from TuxOnIce that you'd like, feel free to
+   ask. We try to be obliging, within reason.
+
+   Patches are welcome. Please send to the list.
+
+10. How does it work?
+
+   TuxOnIce does its work in a number of steps.
+
+   a. Freezing system activity.
+
+   The first main stage in hibernating is to stop all other activity. This is
+   achieved in stages. Processes are considered in fours groups, which we will
+   describe in reverse order for clarity's sake: Threads with the PF_NOFREEZE
+   flag, kernel threads without this flag, userspace processes with the
+   PF_SYNCTHREAD flag and all other processes. The first set (PF_NOFREEZE) are
+   untouched by the refrigerator code. They are allowed to run during hibernating
+   and resuming, and are used to support user interaction, storage access or the
+   like. Other kernel threads (those unneeded while hibernating) are frozen last.
+   This leaves us with userspace processes that need to be frozen. When a
+   process enters one of the *_sync system calls, we set a PF_SYNCTHREAD flag on
+   that process for the duration of that call. Processes that have this flag are
+   frozen after processes without it, so that we can seek to ensure that dirty
+   data is synced to disk as quickly as possible in a situation where other
+   processes may be submitting writes at the same time. Freezing the processes
+   that are submitting data stops new I/O from being submitted. Syncthreads can
+   then cleanly finish their work. So the order is:
+
+   - Userspace processes without PF_SYNCTHREAD or PF_NOFREEZE;
+   - Userspace processes with PF_SYNCTHREAD (they won't have NOFREEZE);
+   - Kernel processes without PF_NOFREEZE.
+
+   b. Eating memory.
+
+   For a successful hibernation cycle, you need to have enough disk space to store the
+   image and enough memory for the various limitations of TuxOnIce's
+   algorithm. You can also specify a maximum image size. In order to attain
+   to those constraints, TuxOnIce may 'eat' memory. If, after freezing
+   processes, the constraints aren't met, TuxOnIce will thaw all the
+   other processes and begin to eat memory until its calculations indicate
+   the constraints are met. It will then freeze processes again and recheck
+   its calculations.
+
+   c. Allocation of storage.
+
+   Next, TuxOnIce allocates the storage that will be used to save
+   the image.
+
+   The core of TuxOnIce knows nothing about how or where pages are stored. We
+   therefore request the active allocator (remember you might have compiled in
+   more than one!) to allocate enough storage for our expect image size. If
+   this request cannot be fulfilled, we eat more memory and try again. If it
+   is fulfiled, we seek to allocate additional storage, just in case our
+   expected compression ratio (if any) isn't achieved. This time, however, we
+   just continue if we can't allocate enough storage.
+
+   If these calls to our allocator change the characteristics of the image
+   such that we haven't allocated enough memory, we also loop. (The allocator
+   may well need to allocate space for its storage information).
+
+   d. Write the first part of the image.
+
+   TuxOnIce stores the image in two sets of pages called 'pagesets'.
+   Pageset 2 contains pages on the active and inactive lists; essentially
+   the page cache. Pageset 1 contains all other pages, including the kernel.
+   We use two pagesets for one important reason: We need to make an atomic copy
+   of the kernel to ensure consistency of the image. Without a second pageset,
+   that would limit us to an image that was at most half the amount of memory
+   available. Using two pagesets allows us to store a full image. Since pageset
+   2 pages won't be needed in saving pageset 1, we first save pageset 2 pages.
+   We can then make our atomic copy of the remaining pages using both pageset 2
+   pages and any other pages that are free. While saving both pagesets, we are
+   careful not to corrupt the image. Among other things, we use lowlevel block
+   I/O routines that don't change the pagecache contents.
+
+   The next step, then, is writing pageset 2.
+
+   e. Suspending drivers and storing processor context.
+
+   Having written pageset2, TuxOnIce calls the power management functions to
+   notify drivers of the hibernation, and saves the processor state in preparation
+   for the atomic copy of memory we are about to make.
+
+   f. Atomic copy.
+
+   At this stage, everything else but the TuxOnIce code is halted. Processes
+   are frozen or idling, drivers are quiesced and have stored (ideally and where
+   necessary) their configuration in memory we are about to atomically copy.
+   In our lowlevel architecture specific code, we have saved the CPU state.
+   We can therefore now do our atomic copy before resuming drivers etc.
+
+   g. Save the atomic copy (pageset 1).
+
+   TuxOnice can then write the atomic copy of the remaining pages. Since we
+   have copied the pages into other locations, we can continue to use the
+   normal block I/O routines without fear of corruption our image.
+
+   f. Save the image header.
+
+   Nearly there! We save our settings and other parameters needed for
+   reloading pageset 1 in an 'image header'. We also tell our allocator to
+   serialise its data at this stage, so that it can reread the image at resume
+   time.
+
+   g. Set the image header.
+
+   Finally, we edit the header at our resume= location. The signature is
+   changed by the allocator to reflect the fact that an image exists, and to
+   point to the start of that data if necessary (swap allocator).
+
+   h. Power down.
+
+   Or reboot if we're debugging and the appropriate option is selected.
+
+   Whew!
+
+   Reloading the image.
+   --------------------
+
+   Reloading the image is essentially the reverse of all the above. We load
+   our copy of pageset 1, being careful to choose locations that aren't going
+   to be overwritten as we copy it back (We start very early in the boot
+   process, so there are no other processes to quiesce here). We then copy
+   pageset 1 back to its original location in memory and restore the process
+   context. We are now running with the original kernel. Next, we reload the
+   pageset 2 pages, free the memory and swap used by TuxOnIce, restore
+   the pageset header and restart processes. Sounds easy in comparison to
+   hibernating, doesn't it!
+
+   There is of course more to TuxOnIce than this, but this explanation
+   should be a good start. If there's interest, I'll write further
+   documentation on range pages and the low level I/O.
+
+11. Who wrote TuxOnIce?
+
+   (Answer based on the writings of Florent Chabaud, credits in files and
+   Nigel's limited knowledge; apologies to anyone missed out!)
+
+   The main developers of TuxOnIce have been...
+
+   Gabor Kuti
+   Pavel Machek
+   Florent Chabaud
+   Bernard Blackham
+   Nigel Cunningham
+
+   Significant portions of swsusp, the code in the vanilla kernel which
+   TuxOnIce enhances, have been worked on by Rafael Wysocki. Thanks should
+   also be expressed to him.
+
+   The above mentioned developers have been aided in their efforts by a host
+   of hundreds, if not thousands of testers and people who have submitted bug
+   fixes & suggestions. Of special note are the efforts of Michael Frank, who
+   had his computers repetitively hibernate and resume for literally tens of
+   thousands of cycles and developed scripts to stress the system and test
+   TuxOnIce far beyond the point most of us (Nigel included!) would consider
+   testing. His efforts have contributed as much to TuxOnIce as any of the
+   names above.
diff --git a/MAINTAINERS b/MAINTAINERS
index 6ee06ea47..ef7947adf 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11181,6 +11181,13 @@ S:	Maintained
 F:	drivers/tc/
 F:	include/linux/tc.h
 
+TUXONICE (ENHANCED HIBERNATION)
+P:	Nigel Cunningham
+M:	nigel@nigelcunningham.com.au
+L:	tuxonice-devel@tuxonice.net
+W:	http://tuxonice.net
+S:	Maintained
+
 U14-34F SCSI DRIVER
 M:	Dario Ballabio <ballabio_dario@emc.com>
 L:	linux-scsi@vger.kernel.org
diff --git a/arch/x86/kernel/espfix_64.c b/arch/x86/kernel/espfix_64.c
index 4d38416e2..a457bce46 100644
--- a/arch/x86/kernel/espfix_64.c
+++ b/arch/x86/kernel/espfix_64.c
@@ -173,6 +173,7 @@ void init_espfix_ap(int cpu)
 		struct page *page = alloc_pages_node(node, PGALLOC_GFP, 0);
 
 		pmd_p = (pmd_t *)page_address(page);
+                SetPageTOI_Untracked(virt_to_page(pmd_p));
 		pud = __pud(__pa(pmd_p) | (PGTABLE_PROT & ptemask));
 		paravirt_alloc_pmd(&init_mm, __pa(pmd_p) >> PAGE_SHIFT);
 		for (n = 0; n < ESPFIX_PUD_CLONES; n++)
@@ -185,6 +186,7 @@ void init_espfix_ap(int cpu)
 		struct page *page = alloc_pages_node(node, PGALLOC_GFP, 0);
 
 		pte_p = (pte_t *)page_address(page);
+                SetPageTOI_Untracked(virt_to_page(pte_p));
 		pmd = __pmd(__pa(pte_p) | (PGTABLE_PROT & ptemask));
 		paravirt_alloc_pte(&init_mm, __pa(pte_p) >> PAGE_SHIFT);
 		for (n = 0; n < ESPFIX_PMD_CLONES; n++)
@@ -193,6 +195,7 @@ void init_espfix_ap(int cpu)
 
 	pte_p = pte_offset_kernel(&pmd, addr);
 	stack_page = page_address(alloc_pages_node(node, GFP_KERNEL, 0));
+        SetPageTOI_Untracked(virt_to_page(stack_page));
 	pte = __pte(__pa(stack_page) | (__PAGE_KERNEL_RO & ptemask));
 	for (n = 0; n < ESPFIX_PTE_CLONES; n++)
 		set_pte(&pte_p[n*PTE_STRIDE], pte);
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 3d743da82..4b20bb75b 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -12,6 +12,7 @@
 #include <linux/percpu.h>
 #include <linux/timex.h>
 #include <linux/static_key.h>
+#include <linux/mm.h>
 
 #include <asm/hpet.h>
 #include <asm/timer.h>
@@ -195,6 +196,10 @@ static void cyc2ns_init(int cpu)
 
 	c2n->head = c2n->data;
 	c2n->tail = c2n->data;
+
+        // Don't let TuxOnIce make data RO - a secondary CPU will cause a triple fault
+        // if it loads microcode, which then does a printk, which may end up invoking cycles_2_ns
+        SetPageTOI_Untracked(virt_to_page(c2n));
 }
 
 static inline unsigned long long cycles_2_ns(unsigned long long cyc)
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index e830c71a1..8d2472be4 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -13,6 +13,7 @@
 #include <linux/hugetlb.h>		/* hstate_index_to_shift	*/
 #include <linux/prefetch.h>		/* prefetchw			*/
 #include <linux/context_tracking.h>	/* exception_enter(), ...	*/
+#include <linux/tuxonice.h>             /* incremental image support    */
 #include <linux/uaccess.h>		/* faulthandler_disabled()	*/
 
 #include <asm/traps.h>			/* dotraplinkage, ...		*/
@@ -662,6 +663,10 @@ no_context(struct pt_regs *regs, unsigned long error_code,
 	unsigned long flags;
 	int sig;
 
+        if (toi_make_writable(init_mm.pgd, address)) {
+            return;
+        }
+
 	/* Are we prepared to handle this kernel fault? */
 	if (fixup_exception(regs)) {
 		/*
@@ -916,10 +921,101 @@ mm_fault_error(struct pt_regs *regs, unsigned long error_code,
 	}
 }
 
+#ifdef CONFIG_TOI_INCREMENTAL
+/**
+ * _toi_do_cbw - Do a copy-before-write before letting the faulting process continue
+ */
+static void toi_do_cbw(struct page *page)
+{
+    struct toi_cbw_state *state = this_cpu_ptr(&toi_cbw_states);
+
+    state->active = 1;
+    wmb();
+
+    if (state->enabled && state->next && PageTOI_CBW(page)) {
+        struct toi_cbw *this = state->next;
+        memcpy(this->virt, page_address(page), PAGE_SIZE);
+        this->pfn = page_to_pfn(page);
+        state->next = this->next;
+    }
+
+    state->active = 0;
+}
+
+/**
+ * _toi_make_writable - Defuse TOI's write protection
+ */
+int _toi_make_writable(pte_t *pte)
+{
+    struct page *page = pte_page(*pte);
+    if (PageTOI_RO(page)) {
+        pgd_t *pgd = __va(read_cr3());
+        /*
+         * If this is a TuxOnIce caused fault, we may not have permission to
+         * write to a page needed to reset the permissions of the original
+         * page. Use swapper_pg_dir to get around this.
+         */
+        load_cr3(swapper_pg_dir);
+
+        set_pte_atomic(pte, pte_mkwrite(*pte));
+        SetPageTOI_Dirty(page);
+        ClearPageTOI_RO(page);
+
+        toi_do_cbw(page);
+
+        load_cr3(pgd);
+        return 1;
+    }
+    return 0;
+}
+
+/**
+ * toi_make_writable - Handle a (potential) fault caused by TOI's write protection
+ *
+ * Make a page writable that was protected. Might be because of a fault, or
+ * because we're allocating it and want it to be untracked.
+ *
+ * Note that in the fault handling case, we don't care about the error code. If
+ * called from the double fault handler, we won't have one. We just check to
+ * see if the page was made RO by TOI, and mark it dirty/release the protection
+ * if it was.
+ */
+int toi_make_writable(pgd_t *pgd, unsigned long address)
+{
+    pud_t *pud;
+    pmd_t *pmd;
+    pte_t *pte;
+
+    pgd = pgd + pgd_index(address);
+    if (!pgd_present(*pgd))
+        return 0;
+
+    pud = pud_offset(pgd, address);
+    if (!pud_present(*pud))
+        return 0;
+
+    if (pud_large(*pud))
+        return _toi_make_writable((pte_t *) pud);
+
+    pmd = pmd_offset(pud, address);
+    if (!pmd_present(*pmd))
+        return 0;
+
+    if (pmd_large(*pmd))
+        return _toi_make_writable((pte_t *) pmd);
+
+    pte = pte_offset_kernel(pmd, address);
+    if (!pte_present(*pte))
+        return 0;
+
+    return _toi_make_writable(pte);
+}
+#endif
+
 static int spurious_fault_check(unsigned long error_code, pte_t *pte)
 {
 	if ((error_code & PF_WRITE) && !pte_write(*pte))
-		return 0;
+                return 0;
 
 	if ((error_code & PF_INSTR) && !pte_exec(*pte))
 		return 0;
@@ -1082,6 +1178,15 @@ __do_page_fault(struct pt_regs *regs, unsigned long error_code,
 		kmemcheck_hide(regs);
 	prefetchw(&mm->mmap_sem);
 
+        /*
+         * Detect and handle page faults due to TuxOnIce making pages read-only
+         * so that it can create incremental images.
+         *
+         * Do it early to avoid double faults.
+         */
+        if (unlikely(toi_make_writable(init_mm.pgd, address)))
+            return;
+
 	if (unlikely(kmmio_fault(regs, address)))
 		return;
 
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index 493f54172..695ac7d37 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -150,9 +150,10 @@ static int page_size_mask;
 
 static void __init probe_page_size_mask(void)
 {
-#if !defined(CONFIG_DEBUG_PAGEALLOC) && !defined(CONFIG_KMEMCHECK)
+#if !defined(CONFIG_DEBUG_PAGEALLOC) && !defined(CONFIG_KMEMCHECK) && !defined(CONFIG_TOI_INCREMENTAL)
 	/*
-	 * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
+         * For CONFIG_DEBUG_PAGEALLOC or TuxOnIce's incremental image support,
+         * identity mapping will use small pages.
 	 * This will simplify cpa(), which otherwise needs to support splitting
 	 * large pages into small in interrupt context, etc.
 	 */
diff --git a/block/Makefile b/block/Makefile
index 4a3668393..37afa486e 100644
--- a/block/Makefile
+++ b/block/Makefile
@@ -7,7 +7,7 @@ obj-$(CONFIG_BLOCK) := bio.o elevator.o blk-core.o blk-tag.o blk-sysfs.o \
 			blk-exec.o blk-merge.o blk-softirq.o blk-timeout.o \
 			blk-lib.o blk-mq.o blk-mq-tag.o \
 			blk-mq-sysfs.o blk-mq-cpu.o blk-mq-cpumap.o ioctl.o \
-			genhd.o scsi_ioctl.o partition-generic.o ioprio.o \
+			uuid.o genhd.o scsi_ioctl.o partition-generic.o ioprio.o \
 			badblocks.o partitions/
 
 obj-$(CONFIG_BOUNCE)	+= bounce.o
diff --git a/block/blk-core.c b/block/blk-core.c
index b83d29755..64d137b04 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -48,6 +48,8 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(block_unplug);
 
 DEFINE_IDA(blk_queue_ida);
 
+int trap_non_toi_io;
+
 /*
  * For the allocated request tables
  */
@@ -2104,6 +2106,9 @@ blk_qc_t submit_bio(int rw, struct bio *bio)
 {
 	bio->bi_rw |= rw;
 
+	if (unlikely(trap_non_toi_io))
+		BUG_ON(!bio_flagged(bio, BIO_TOI));
+
 	/*
 	 * If it's a regular read/write or a barrier with data attached,
 	 * go through the normal accounting stuff before submission.
diff --git a/block/genhd.c b/block/genhd.c
index 9f42526b4..7a6a655d8 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -18,6 +18,8 @@
 #include <linux/kobj_map.h>
 #include <linux/mutex.h>
 #include <linux/idr.h>
+#include <linux/ctype.h>
+#include <linux/fs_uuid.h>
 #include <linux/log2.h>
 #include <linux/pm_runtime.h>
 #include <linux/badblocks.h>
@@ -1417,6 +1419,85 @@ int invalidate_partition(struct gendisk *disk, int partno)
 
 EXPORT_SYMBOL(invalidate_partition);
 
+dev_t blk_lookup_fs_info(struct fs_info *seek)
+{
+	dev_t devt = MKDEV(0, 0);
+	struct class_dev_iter iter;
+	struct device *dev;
+	int best_score = 0;
+
+	class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
+	while (best_score < 3 && (dev = class_dev_iter_next(&iter))) {
+		struct gendisk *disk = dev_to_disk(dev);
+		struct disk_part_iter piter;
+		struct hd_struct *part;
+
+		disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
+
+		while (best_score < 3 && (part = disk_part_iter_next(&piter))) {
+			int score = part_matches_fs_info(part, seek);
+			if (score > best_score) {
+				devt = part_devt(part);
+				best_score = score;
+			}
+		}
+		disk_part_iter_exit(&piter);
+	}
+	class_dev_iter_exit(&iter);
+	return devt;
+}
+
+/* Caller uses NULL, key to start. For each match found, we return a bdev on
+ * which we have done blkdev_get, and we do the blkdev_put on block devices
+ * that are passed to us. When no more matches are found, we return NULL.
+ */
+struct block_device *next_bdev_of_type(struct block_device *last,
+	const char *key)
+{
+	dev_t devt = MKDEV(0, 0);
+	struct class_dev_iter iter;
+	struct device *dev;
+	struct block_device *next = NULL, *bdev;
+	int got_last = 0;
+
+	if (!key)
+		goto out;
+
+	class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
+	while (!devt && (dev = class_dev_iter_next(&iter))) {
+		struct gendisk *disk = dev_to_disk(dev);
+		struct disk_part_iter piter;
+		struct hd_struct *part;
+
+		disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
+
+		while ((part = disk_part_iter_next(&piter))) {
+			bdev = bdget(part_devt(part));
+			if (last && !got_last) {
+				if (last == bdev)
+					got_last = 1;
+				continue;
+			}
+
+			if (blkdev_get(bdev, FMODE_READ, 0))
+				continue;
+
+			if (bdev_matches_key(bdev, key)) {
+				next = bdev;
+				break;
+			}
+
+			blkdev_put(bdev, FMODE_READ);
+		}
+		disk_part_iter_exit(&piter);
+	}
+	class_dev_iter_exit(&iter);
+out:
+	if (last)
+		blkdev_put(last, FMODE_READ);
+	return next;
+}
+
 /*
  * Disk events - monitor disk events like media change and eject request.
  */
diff --git a/block/uuid.c b/block/uuid.c
new file mode 100644
index 000000000..4610d7b8f
--- /dev/null
+++ b/block/uuid.c
@@ -0,0 +1,509 @@
+#include <linux/blkdev.h>
+#include <linux/ctype.h>
+#include <linux/fs_uuid.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+
+static int debug_enabled;
+
+#define PRINTK(fmt, args...) do {					\
+	if (debug_enabled)						\
+		printk(KERN_DEBUG fmt, ## args);			\
+	} while(0)
+
+#define PRINT_HEX_DUMP(v1, v2, v3, v4, v5, v6, v7, v8)			\
+	do {								\
+		if (debug_enabled)					\
+			print_hex_dump(v1, v2, v3, v4, v5, v6, v7, v8);	\
+	} while(0)
+
+/*
+ * Simple UUID translation
+ */
+
+struct uuid_info {
+	const char *key;
+	const char *name;
+	long bkoff;
+	unsigned sboff;
+	unsigned sig_len;
+	const char *magic;
+	int uuid_offset;
+	int last_mount_offset;
+	int last_mount_size;
+};
+
+/*
+ * Based on libuuid's blkid_magic array. Note that I don't
+ * have uuid offsets for all of these yet - mssing ones are 0x0.
+ * Further information welcome.
+ *
+ * Rearranged by page of fs signature for optimisation.
+ */
+static struct uuid_info uuid_list[] = {
+ { NULL, "oracleasm", 0, 32, 8, "ORCLDISK", 0x0, 0, 0 },
+ { "ntfs", "ntfs", 0, 3, 8, "NTFS    ", 0x0, 0, 0 },
+ { "vfat", "vfat", 0, 0x52, 5, "MSWIN", 0x0, 0, 0 },
+ { "vfat", "vfat", 0, 0x52, 8, "FAT32   ", 0x0, 0, 0 },
+ { "vfat", "vfat", 0, 0x36, 5, "MSDOS", 0x0, 0, 0 },
+ { "vfat", "vfat", 0, 0x36, 8, "FAT16   ", 0x0, 0, 0 },
+ { "vfat", "vfat", 0, 0x36, 8, "FAT12   ", 0x0, 0, 0 },
+ { "vfat", "vfat", 0, 0, 1, "\353", 0x0, 0, 0 },
+ { "vfat", "vfat", 0, 0, 1, "\351", 0x0, 0, 0 },
+ { "vfat", "vfat", 0, 0x1fe, 2, "\125\252", 0x0, 0, 0 },
+ { "xfs", "xfs", 0, 0, 4, "XFSB", 0x20, 0, 0 },
+ { "romfs", "romfs", 0, 0, 8, "-rom1fs-", 0x0, 0, 0 },
+ { "bfs", "bfs", 0, 0, 4, "\316\372\173\033", 0, 0, 0 },
+ { "cramfs", "cramfs", 0, 0, 4, "E=\315\050", 0x0, 0, 0 },
+ { "qnx4", "qnx4", 0, 4, 6, "QNX4FS", 0, 0, 0 },
+ { NULL, "crypt_LUKS", 0, 0, 6, "LUKS\xba\xbe", 0x0, 0, 0 },
+ { "squashfs", "squashfs", 0, 0, 4, "sqsh", 0, 0, 0 },
+ { "squashfs", "squashfs", 0, 0, 4, "hsqs", 0, 0, 0 },
+ { "ocfs", "ocfs", 0, 8, 9, "OracleCFS", 0x0, 0, 0 },
+ { "lvm2pv", "lvm2pv", 0, 0x018, 8, "LVM2 001", 0x0, 0, 0 },
+ { "sysv", "sysv", 0, 0x3f8, 4, "\020~\030\375", 0, 0, 0 },
+ { "ext", "ext", 1, 0x38, 2, "\123\357", 0x468, 0x42c, 4 },
+ { "minix", "minix", 1, 0x10, 2, "\177\023", 0, 0, 0 },
+ { "minix", "minix", 1, 0x10, 2, "\217\023", 0, 0, 0 },
+ { "minix", "minix", 1, 0x10, 2, "\150\044", 0, 0, 0 },
+ { "minix", "minix", 1, 0x10, 2, "\170\044", 0, 0, 0 },
+ { "lvm2pv", "lvm2pv", 1, 0x018, 8, "LVM2 001", 0x0, 0, 0 },
+ { "vxfs", "vxfs", 1, 0, 4, "\365\374\001\245", 0, 0, 0 },
+ { "hfsplus", "hfsplus", 1, 0, 2, "BD", 0x0, 0, 0 },
+ { "hfsplus", "hfsplus", 1, 0, 2, "H+", 0x0, 0, 0 },
+ { "hfsplus", "hfsplus", 1, 0, 2, "HX", 0x0, 0, 0 },
+ { "hfs", "hfs", 1, 0, 2, "BD", 0x0, 0, 0 },
+ { "ocfs2", "ocfs2", 1, 0, 6, "OCFSV2", 0x0, 0, 0 },
+ { "lvm2pv", "lvm2pv", 0, 0x218, 8, "LVM2 001", 0x0, 0, 0 },
+ { "lvm2pv", "lvm2pv", 1, 0x218, 8, "LVM2 001", 0x0, 0, 0 },
+ { "ocfs2", "ocfs2", 2, 0, 6, "OCFSV2", 0x0, 0, 0 },
+ { "swap", "swap", 0, 0xff6, 10, "SWAP-SPACE", 0x40c, 0, 0 },
+ { "swap", "swap", 0, 0xff6, 10, "SWAPSPACE2", 0x40c, 0, 0 },
+ { "swap", "swsuspend", 0, 0xff6, 9, "S1SUSPEND", 0x40c, 0, 0 },
+ { "swap", "swsuspend", 0, 0xff6, 9, "S2SUSPEND", 0x40c, 0, 0 },
+ { "swap", "swsuspend", 0, 0xff6, 9, "ULSUSPEND", 0x40c, 0, 0 },
+ { "ocfs2", "ocfs2", 4, 0, 6, "OCFSV2", 0x0, 0, 0 },
+ { "ocfs2", "ocfs2", 8, 0, 6, "OCFSV2", 0x0, 0, 0 },
+ { "hpfs", "hpfs", 8, 0, 4, "I\350\225\371", 0, 0, 0 },
+ { "reiserfs", "reiserfs", 8, 0x34, 8, "ReIsErFs", 0x10054, 0, 0 },
+ { "reiserfs", "reiserfs", 8, 20, 8, "ReIsErFs", 0x10054, 0, 0 },
+ { "zfs", "zfs", 8, 0, 8, "\0\0\x02\xf5\xb0\x07\xb1\x0c", 0x0, 0, 0 },
+ { "zfs", "zfs", 8, 0, 8, "\x0c\xb1\x07\xb0\xf5\x02\0\0", 0x0, 0, 0 },
+ { "ufs", "ufs", 8, 0x55c, 4, "T\031\001\000", 0, 0, 0 },
+ { "swap", "swap", 0, 0x1ff6, 10, "SWAP-SPACE", 0x40c, 0, 0 },
+ { "swap", "swap", 0, 0x1ff6, 10, "SWAPSPACE2", 0x40c, 0, 0 },
+ { "swap", "swsuspend", 0, 0x1ff6, 9, "S1SUSPEND", 0x40c, 0, 0 },
+ { "swap", "swsuspend", 0, 0x1ff6, 9, "S2SUSPEND", 0x40c, 0, 0 },
+ { "swap", "swsuspend", 0, 0x1ff6, 9, "ULSUSPEND", 0x40c, 0, 0 },
+ { "reiserfs", "reiserfs", 64, 0x34, 9, "ReIsEr2Fs", 0x10054, 0, 0 },
+ { "reiserfs", "reiserfs", 64, 0x34, 9, "ReIsEr3Fs", 0x10054, 0, 0 },
+ { "reiserfs", "reiserfs", 64, 0x34, 8, "ReIsErFs", 0x10054, 0, 0 },
+ { "reiser4", "reiser4", 64, 0, 7, "ReIsEr4", 0x100544, 0, 0 },
+ { "gfs2", "gfs2", 64, 0, 4, "\x01\x16\x19\x70", 0x0, 0, 0 },
+ { "gfs", "gfs", 64, 0, 4, "\x01\x16\x19\x70", 0x0, 0, 0 },
+ { "btrfs", "btrfs", 64, 0x40, 8, "_BHRfS_M", 0x0, 0, 0 },
+ { "swap", "swap", 0, 0x3ff6, 10, "SWAP-SPACE", 0x40c, 0, 0 },
+ { "swap", "swap", 0, 0x3ff6, 10, "SWAPSPACE2", 0x40c, 0, 0 },
+ { "swap", "swsuspend", 0, 0x3ff6, 9, "S1SUSPEND", 0x40c, 0, 0 },
+ { "swap", "swsuspend", 0, 0x3ff6, 9, "S2SUSPEND", 0x40c, 0, 0 },
+ { "swap", "swsuspend", 0, 0x3ff6, 9, "ULSUSPEND", 0x40c, 0, 0 },
+ { "udf", "udf", 32, 1, 5, "BEA01", 0x0, 0, 0 },
+ { "udf", "udf", 32, 1, 5, "BOOT2", 0x0, 0, 0 },
+ { "udf", "udf", 32, 1, 5, "CD001", 0x0, 0, 0 },
+ { "udf", "udf", 32, 1, 5, "CDW02", 0x0, 0, 0 },
+ { "udf", "udf", 32, 1, 5, "NSR02", 0x0, 0, 0 },
+ { "udf", "udf", 32, 1, 5, "NSR03", 0x0, 0, 0 },
+ { "udf", "udf", 32, 1, 5, "TEA01", 0x0, 0, 0 },
+ { "iso9660", "iso9660", 32, 1, 5, "CD001", 0x0, 0, 0 },
+ { "iso9660", "iso9660", 32, 9, 5, "CDROM", 0x0, 0, 0 },
+ { "jfs", "jfs", 32, 0, 4, "JFS1", 0x88, 0, 0 },
+ { "swap", "swap", 0, 0x7ff6, 10, "SWAP-SPACE", 0x40c, 0, 0 },
+ { "swap", "swap", 0, 0x7ff6, 10, "SWAPSPACE2", 0x40c, 0, 0 },
+ { "swap", "swsuspend", 0, 0x7ff6, 9, "S1SUSPEND", 0x40c, 0, 0 },
+ { "swap", "swsuspend", 0, 0x7ff6, 9, "S2SUSPEND", 0x40c, 0, 0 },
+ { "swap", "swsuspend", 0, 0x7ff6, 9, "ULSUSPEND", 0x40c, 0, 0 },
+ { "swap", "swap", 0, 0xfff6, 10, "SWAP-SPACE", 0x40c, 0, 0 },
+ { "swap", "swap", 0, 0xfff6, 10, "SWAPSPACE2", 0x40c, 0, 0 },
+ { "swap", "swsuspend", 0, 0xfff6, 9, "S1SUSPEND", 0x40c, 0, 0 },
+ { "swap", "swsuspend", 0, 0xfff6, 9, "S2SUSPEND", 0x40c, 0, 0 },
+ { "swap", "swsuspend", 0, 0xfff6, 9, "ULSUSPEND", 0x40c, 0, 0 },
+ { "zfs", "zfs", 264, 0, 8, "\0\0\x02\xf5\xb0\x07\xb1\x0c", 0x0, 0, 0 },
+ { "zfs", "zfs", 264, 0, 8, "\x0c\xb1\x07\xb0\xf5\x02\0\0", 0x0, 0, 0 },
+ { NULL, NULL, 0, 0, 0, NULL, 0x0, 0, 0 }
+};
+
+static int null_uuid(const char *uuid)
+{
+	int i;
+
+	for (i = 0; i < 16 && !uuid[i]; i++);
+
+	return (i == 16);
+}
+
+
+static void uuid_end_bio(struct bio *bio)
+{
+	struct page *page = bio->bi_io_vec[0].bv_page;
+
+        if (bio->bi_error)
+            SetPageError(page);
+
+	unlock_page(page);
+	bio_put(bio);
+}
+
+
+/**
+ * submit - submit BIO request
+ * @dev: The block device we're using.
+ * @page_num: The page we're reading.
+ *
+ * Based on Patrick Mochell's pmdisk code from long ago: "Straight from the
+ * textbook - allocate and initialize the bio. If we're writing, make sure
+ * the page is marked as dirty. Then submit it and carry on."
+ **/
+static struct page *read_bdev_page(struct block_device *dev, int page_num)
+{
+	struct bio *bio = NULL;
+	struct page *page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
+
+	if (!page) {
+		printk(KERN_ERR "Failed to allocate a page for reading data "
+				"in UUID checks.");
+		return NULL;
+	}
+
+	bio = bio_alloc(GFP_NOFS, 1);
+	bio->bi_bdev = dev;
+	bio->bi_iter.bi_sector = page_num << 3;
+	bio->bi_end_io = uuid_end_bio;
+	bio->bi_flags |= (1 << BIO_TOI);
+
+	PRINTK("Submitting bio on device %lx, page %d using bio %p and page %p.\n",
+			(unsigned long) dev->bd_dev, page_num, bio, page);
+
+	if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
+		printk(KERN_DEBUG "ERROR: adding page to bio at %d\n",
+				page_num);
+		bio_put(bio);
+		__free_page(page);
+		printk(KERN_DEBUG "read_bdev_page freed page %p (in error "
+				"path).\n", page);
+		return NULL;
+	}
+
+	lock_page(page);
+	submit_bio(READ | REQ_SYNC, bio);
+
+	wait_on_page_locked(page);
+	if (PageError(page)) {
+		__free_page(page);
+		page = NULL;
+	}
+	return page;
+}
+
+int bdev_matches_key(struct block_device *bdev, const char *key)
+{
+	unsigned char *data = NULL;
+	struct page *data_page = NULL;
+
+	int dev_offset, pg_num, pg_off, i;
+	int last_pg_num = -1;
+	int result = 0;
+	char buf[50];
+
+	if (null_uuid(key)) {
+		PRINTK("Refusing to find a NULL key.\n");
+		return 0;
+	}
+
+	if (!bdev->bd_disk) {
+		bdevname(bdev, buf);
+		PRINTK("bdev %s has no bd_disk.\n", buf);
+		return 0;
+	}
+
+	if (!bdev->bd_disk->queue) {
+		bdevname(bdev, buf);
+		PRINTK("bdev %s has no queue.\n", buf);
+		return 0;
+	}
+
+	for (i = 0; uuid_list[i].name; i++) {
+		struct uuid_info *dat = &uuid_list[i];
+
+		if (!dat->key || strcmp(dat->key, key))
+			continue;
+
+		dev_offset = (dat->bkoff << 10) + dat->sboff;
+		pg_num = dev_offset >> 12;
+		pg_off = dev_offset & 0xfff;
+
+		if ((((pg_num + 1) << 3) - 1) > bdev->bd_part->nr_sects >> 1)
+			continue;
+
+		if (pg_num != last_pg_num) {
+			if (data_page) {
+				kunmap(data_page);
+				__free_page(data_page);
+			}
+			data_page = read_bdev_page(bdev, pg_num);
+			if (!data_page)
+				continue;
+			data = kmap(data_page);
+		}
+
+		last_pg_num = pg_num;
+
+		if (strncmp(&data[pg_off], dat->magic, dat->sig_len))
+			continue;
+
+		result = 1;
+		break;
+	}
+
+	if (data_page) {
+		kunmap(data_page);
+		__free_page(data_page);
+	}
+
+	return result;
+}
+
+/* 
+ * part_matches_fs_info - Does the given partition match the details given?
+ *
+ * Returns a score saying how good the match is.
+ * 0 = no UUID match.
+ * 1 = UUID but last mount time differs.
+ * 2 = UUID, last mount time but not dev_t
+ * 3 = perfect match
+ *
+ * This lets us cope elegantly with probing resulting in dev_ts changing
+ * from boot to boot, and with the case where a user copies a partition
+ * (UUID is non unique), and we need to check the last mount time of the
+ * correct partition.
+ */
+int part_matches_fs_info(struct hd_struct *part, struct fs_info *seek)
+{
+	struct block_device *bdev;
+	struct fs_info *got;
+	int result = 0;
+	char buf[50];
+
+	if (null_uuid((char *) &seek->uuid)) {
+		PRINTK("Refusing to find a NULL uuid.\n");
+		return 0;
+	}
+
+	bdev = bdget(part_devt(part));
+
+	PRINTK("part_matches fs info considering %x.\n", part_devt(part));
+
+	if (blkdev_get(bdev, FMODE_READ, 0)) {
+		PRINTK("blkdev_get failed.\n");
+		return 0;
+	}
+
+	if (!bdev->bd_disk) {
+		bdevname(bdev, buf);
+		PRINTK("bdev %s has no bd_disk.\n", buf);
+		goto out;
+	}
+
+	if (!bdev->bd_disk->queue) {
+		bdevname(bdev, buf);
+		PRINTK("bdev %s has no queue.\n", buf);
+		goto out;
+	}
+
+	got = fs_info_from_block_dev(bdev);
+
+	if (got && !memcmp(got->uuid, seek->uuid, 16)) {
+		PRINTK(" Have matching UUID.\n");
+		PRINTK(" Got: LMS %d, LM %p.\n", got->last_mount_size, got->last_mount);
+		PRINTK(" Seek: LMS %d, LM %p.\n", seek->last_mount_size, seek->last_mount);
+		result = 1;
+
+		if (got->last_mount_size == seek->last_mount_size &&
+		    got->last_mount && seek->last_mount &&
+		    !memcmp(got->last_mount, seek->last_mount,
+			    got->last_mount_size)) {
+			result = 2;
+
+			PRINTK(" Matching last mount time.\n");
+
+			if (part_devt(part) == seek->dev_t) {
+				result = 3;
+				PRINTK(" Matching dev_t.\n");
+			} else
+				PRINTK("Dev_ts differ (%x vs %x).\n", part_devt(part), seek->dev_t);
+		}
+	}
+
+	PRINTK(" Score for %x is %d.\n", part_devt(part), result);
+	free_fs_info(got);
+out:
+	blkdev_put(bdev, FMODE_READ);
+	return result;
+}
+
+void free_fs_info(struct fs_info *fs_info)
+{
+	if (!fs_info || IS_ERR(fs_info))
+		return;
+
+	if (fs_info->last_mount)
+		kfree(fs_info->last_mount);
+
+	kfree(fs_info);
+}
+
+struct fs_info *fs_info_from_block_dev(struct block_device *bdev)
+{
+	unsigned char *data = NULL;
+	struct page *data_page = NULL;
+
+	int dev_offset, pg_num, pg_off;
+	int uuid_pg_num, uuid_pg_off, i;
+	unsigned char *uuid_data = NULL;
+	struct page *uuid_data_page = NULL;
+
+	int last_pg_num = -1, last_uuid_pg_num = 0;
+	char buf[50];
+	struct fs_info *fs_info = NULL;
+
+	bdevname(bdev, buf);
+
+	PRINTK("uuid_from_block_dev looking for partition type of %s.\n", buf);
+
+	for (i = 0; uuid_list[i].name; i++) {
+		struct uuid_info *dat = &uuid_list[i];
+		dev_offset = (dat->bkoff << 10) + dat->sboff;
+		pg_num = dev_offset >> 12;
+		pg_off = dev_offset & 0xfff;
+		uuid_pg_num = dat->uuid_offset >> 12;
+		uuid_pg_off = dat->uuid_offset & 0xfff;
+
+		if ((((pg_num + 1) << 3) - 1) > bdev->bd_part->nr_sects >> 1)
+			continue;
+
+		/* Ignore partition types with no UUID offset */
+		if (!dat->uuid_offset)
+			continue;
+
+		if (pg_num != last_pg_num) {
+			if (data_page) {
+				kunmap(data_page);
+				__free_page(data_page);
+			}
+			data_page = read_bdev_page(bdev, pg_num);
+			if (!data_page)
+				continue;
+			data = kmap(data_page);
+		}
+
+		last_pg_num = pg_num;
+
+		if (strncmp(&data[pg_off], dat->magic, dat->sig_len))
+			continue;
+
+		PRINTK("This partition looks like %s.\n", dat->name);
+
+		fs_info = kzalloc(sizeof(struct fs_info), GFP_KERNEL);
+
+		if (!fs_info) {
+			PRINTK("Failed to allocate fs_info struct.");
+			fs_info = ERR_PTR(-ENOMEM);
+			break;
+		}
+
+		/* UUID can't be off the end of the disk */
+		if ((uuid_pg_num > bdev->bd_part->nr_sects >> 3) ||
+				!dat->uuid_offset)
+			goto no_uuid;
+
+		if (!uuid_data || uuid_pg_num != last_uuid_pg_num) {
+			/* No need to reread the page from above */
+			if (uuid_pg_num == pg_num && uuid_data)
+				memcpy(uuid_data, data, PAGE_SIZE);
+			else {
+				if (uuid_data_page) {
+					kunmap(uuid_data_page);
+					__free_page(uuid_data_page);
+				}
+				uuid_data_page = read_bdev_page(bdev, uuid_pg_num);
+				if (!uuid_data_page)
+					continue;
+				uuid_data = kmap(uuid_data_page);
+			}
+		}
+
+		last_uuid_pg_num = uuid_pg_num;
+		memcpy(&fs_info->uuid, &uuid_data[uuid_pg_off], 16);
+		fs_info->dev_t = bdev->bd_dev;
+
+no_uuid:
+		PRINT_HEX_DUMP(KERN_EMERG, "fs_info_from_block_dev "
+				"returning uuid ", DUMP_PREFIX_NONE, 16, 1,
+				fs_info->uuid, 16, 0);
+
+		if (dat->last_mount_size) {
+			int pg = dat->last_mount_offset >> 12, sz;
+			int off = dat->last_mount_offset & 0xfff;
+			struct page *last_mount = read_bdev_page(bdev, pg);
+			unsigned char *last_mount_data;
+			char *ptr;
+
+			if (!last_mount) {
+				fs_info = ERR_PTR(-ENOMEM);
+				break;
+			}
+			last_mount_data = kmap(last_mount);
+			sz = dat->last_mount_size;
+			ptr = kmalloc(sz, GFP_KERNEL);
+
+			if (!ptr) {
+				printk(KERN_EMERG "fs_info_from_block_dev "
+					"failed to get memory for last mount "
+					"timestamp.");
+				free_fs_info(fs_info);
+				fs_info = ERR_PTR(-ENOMEM);
+			} else {
+				fs_info->last_mount = ptr;
+				fs_info->last_mount_size = sz;
+				memcpy(ptr, &last_mount_data[off], sz);
+			}
+
+			kunmap(last_mount);
+			__free_page(last_mount);
+		}
+		break;
+	}
+
+	if (data_page) {
+		kunmap(data_page);
+		__free_page(data_page);
+	}
+
+	if (uuid_data_page) {
+		kunmap(uuid_data_page);
+		__free_page(uuid_data_page);
+	}
+
+	return fs_info;
+}
+
+static int __init uuid_debug_setup(char *str)
+{
+	int value;
+
+	if (sscanf(str, "=%d", &value))
+		debug_enabled = value;
+
+	return 1;
+}
+
+__setup("uuid_debug", uuid_debug_setup);
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index 2e8c77e71..8d75300f9 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -137,7 +137,7 @@ int drm_gem_object_init(struct drm_device *dev,
 
 	drm_gem_private_object_init(dev, obj, size);
 
-	filp = shmem_file_setup("drm mm object", size, VM_NORESERVE);
+	filp = shmem_file_setup("drm mm object", size, VM_NORESERVE, 1);
 	if (IS_ERR(filp))
 		return PTR_ERR(filp);
 
diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c
index 4e19d0f9c..aaaf6838d 100644
--- a/drivers/gpu/drm/ttm/ttm_tt.c
+++ b/drivers/gpu/drm/ttm/ttm_tt.c
@@ -339,7 +339,7 @@ int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistent_swap_storage)
 	if (!persistent_swap_storage) {
 		swap_storage = shmem_file_setup("ttm swap",
 						ttm->num_pages << PAGE_SHIFT,
-						0);
+						0, 0);
 		if (IS_ERR(swap_storage)) {
 			pr_err("Failed allocating swap storage\n");
 			return PTR_ERR(swap_storage);
diff --git a/drivers/staging/android/ashmem.c b/drivers/staging/android/ashmem.c
index 5bb1283d1..f4f8f0373 100644
--- a/drivers/staging/android/ashmem.c
+++ b/drivers/staging/android/ashmem.c
@@ -387,7 +387,7 @@ static int ashmem_mmap(struct file *file, struct vm_area_struct *vma)
 			name = asma->name;
 
 		/* ... and allocate the backing shmem file */
-		vmfile = shmem_file_setup(name, asma->size, vma->vm_flags);
+		vmfile = shmem_file_setup(name, asma->size, vma->vm_flags, 0);
 		if (IS_ERR(vmfile)) {
 			ret = PTR_ERR(vmfile);
 			goto out;
diff --git a/fs/drop_caches.c b/fs/drop_caches.c
index d72d52b90..4f591f190 100644
--- a/fs/drop_caches.c
+++ b/fs/drop_caches.c
@@ -8,6 +8,7 @@
 #include <linux/writeback.h>
 #include <linux/sysctl.h>
 #include <linux/gfp.h>
+#include <linux/export.h>
 #include "internal.h"
 
 /* A global variable is a bit ugly, but it keeps the code simple */
@@ -39,6 +40,12 @@ static void drop_pagecache_sb(struct super_block *sb, void *unused)
 	iput(toput_inode);
 }
 
+/* For TuxOnIce */
+void drop_pagecache(void)
+{
+	iterate_supers(drop_pagecache_sb, NULL);
+}
+
 int drop_caches_sysctl_handler(struct ctl_table *table, int write,
 	void __user *buffer, size_t *length, loff_t *ppos)
 {
diff --git a/fs/super.c b/fs/super.c
index 74914b1ba..ad57841f7 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -36,7 +36,7 @@
 #include "internal.h"
 
 
-static LIST_HEAD(super_blocks);
+LIST_HEAD(super_blocks);
 static DEFINE_SPINLOCK(sb_lock);
 
 static char *sb_writers_name[SB_FREEZE_LEVELS] = {
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 88bc64f00..b721a9d63 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -32,6 +32,8 @@
 /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
 #include <linux/blk_types.h>
 
+extern int trap_non_toi_io;
+
 #define BIO_DEBUG
 
 #ifdef BIO_DEBUG
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 86a38ea18..fee9e23a3 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -120,13 +120,14 @@ struct bio {
 #define BIO_QUIET	6	/* Make BIO Quiet */
 #define BIO_CHAIN	7	/* chained bio, ->bi_remaining in effect */
 #define BIO_REFFED	8	/* bio has elevated ->bi_cnt */
+#define BIO_TOI		9	/* bio is TuxOnIce submitted */	
 
 /*
  * Flags starting here get preserved by bio_reset() - this includes
  * BIO_POOL_IDX()
  */
-#define BIO_RESET_BITS	13
-#define BIO_OWNS_VEC	13	/* bio_free() should free bvec */
+#define BIO_RESET_BITS	14
+#define BIO_OWNS_VEC	14	/* bio_free() should free bvec */
 
 /*
  * top 4 bits of bio flags indicate the pool this bio came from
diff --git a/include/linux/fs.h b/include/linux/fs.h
index ae6810021..cf958ec45 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1278,6 +1278,8 @@ struct mm_struct;
 #define UMOUNT_NOFOLLOW	0x00000008	/* Don't follow symlink on umount */
 #define UMOUNT_UNUSED	0x80000000	/* Flag guaranteed to be unused */
 
+extern struct list_head super_blocks;
+
 /* sb->s_iflags */
 #define SB_I_CGROUPWB	0x00000001	/* cgroup-aware writeback enabled */
 #define SB_I_NOEXEC	0x00000002	/* Ignore executables on this fs */
@@ -1774,6 +1776,8 @@ struct super_operations {
 #else
 #define S_DAX		0	/* Make all the DAX code disappear */
 #endif
+#define S_ATOMIC_COPY	16384	/* Pages mapped with this inode need to be
+				   atomically copied (gem) */
 
 /*
  * Note that nosuid etc flags are inode-specific: setting some file-system
@@ -2306,6 +2310,13 @@ extern struct super_block *freeze_bdev(struct block_device *);
 extern void emergency_thaw_all(void);
 extern int thaw_bdev(struct block_device *bdev, struct super_block *sb);
 extern int fsync_bdev(struct block_device *);
+extern int fsync_super(struct super_block *);
+extern int fsync_no_super(struct block_device *);
+#define FS_FREEZER_FUSE 1
+#define FS_FREEZER_NORMAL 2
+#define FS_FREEZER_ALL (FS_FREEZER_FUSE | FS_FREEZER_NORMAL)
+void freeze_filesystems(int which);
+void thaw_filesystems(int which);
 #ifdef CONFIG_FS_DAX
 extern bool blkdev_dax_capable(struct block_device *bdev);
 #else
diff --git a/include/linux/fs_uuid.h b/include/linux/fs_uuid.h
new file mode 100644
index 000000000..3234135b5
--- /dev/null
+++ b/include/linux/fs_uuid.h
@@ -0,0 +1,19 @@
+#include <linux/device.h>
+
+struct hd_struct;
+struct block_device;
+
+struct fs_info {
+	char uuid[16];
+	dev_t dev_t;
+	char *last_mount;
+	int last_mount_size;
+};
+
+int part_matches_fs_info(struct hd_struct *part, struct fs_info *seek);
+dev_t blk_lookup_fs_info(struct fs_info *seek);
+struct fs_info *fs_info_from_block_dev(struct block_device *bdev);
+void free_fs_info(struct fs_info *fs_info);
+int bdev_matches_key(struct block_device *bdev, const char *key);
+struct block_device *next_bdev_of_type(struct block_device *last,
+	const char *key);
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index af1f2b24b..0b6edf722 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -35,7 +35,8 @@ struct vm_area_struct;
 #define ___GFP_DIRECT_RECLAIM	0x400000u
 #define ___GFP_OTHER_NODE	0x800000u
 #define ___GFP_WRITE		0x1000000u
-#define ___GFP_KSWAPD_RECLAIM	0x2000000u
+#define ___GFP_TOI_NOTRACK      0x2000000u
+#define ___GFP_KSWAPD_RECLAIM	0x4000000u
 /* If the above are modified, __GFP_BITS_SHIFT may need updating */
 
 /*
@@ -153,6 +154,7 @@ struct vm_area_struct;
 #define __GFP_REPEAT	((__force gfp_t)___GFP_REPEAT)
 #define __GFP_NOFAIL	((__force gfp_t)___GFP_NOFAIL)
 #define __GFP_NORETRY	((__force gfp_t)___GFP_NORETRY)
+#define __GFP_TOI_NOTRACK	((__force gfp_t)___GFP_TOI_NOTRACK)	/* Allocator wants page untracked by TOI */
 
 /*
  * Action modifiers
@@ -186,7 +188,7 @@ struct vm_area_struct;
 #define __GFP_OTHER_NODE ((__force gfp_t)___GFP_OTHER_NODE)
 
 /* Room for N __GFP_FOO bits */
-#define __GFP_BITS_SHIFT 26
+#define __GFP_BITS_SHIFT 27
 #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
 
 /*
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 516e14944..ccc992c6a 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2225,6 +2225,7 @@ int drop_caches_sysctl_handler(struct ctl_table *, int,
 					void __user *, size_t *, loff_t *);
 #endif
 
+void drop_pagecache(void);
 void drop_slab(void);
 void drop_slab_node(int nid);
 
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 19724e6eb..2e7ecb771 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -101,6 +101,12 @@ enum pageflags {
 #ifdef CONFIG_MEMORY_FAILURE
 	PG_hwpoison,		/* hardware poisoned page. Don't touch */
 #endif
+#ifdef CONFIG_TOI_INCREMENTAL
+	PG_toi_untracked,	/* Don't track dirtiness of this page - assume always dirty */
+	PG_toi_ro,		/* Page was made RO by TOI */
+	PG_toi_cbw,		/* Copy the page before it is written to */
+	PG_toi_dirty,		/* Page has been modified */
+#endif
 #if defined(CONFIG_IDLE_PAGE_TRACKING) && defined(CONFIG_64BIT)
 	PG_young,
 	PG_idle,
@@ -343,6 +349,17 @@ TESTSCFLAG(HWPoison, hwpoison, PF_ANY)
 PAGEFLAG_FALSE(HWPoison)
 #define __PG_HWPOISON 0
 #endif
+#ifdef CONFIG_TOI_INCREMENTAL
+PAGEFLAG(TOI_RO, toi_ro)
+PAGEFLAG(TOI_Dirty, toi_dirty)
+PAGEFLAG(TOI_Untracked, toi_untracked)
+PAGEFLAG(TOI_CBW, toi_cbw)
+#else
+PAGEFLAG_FALSE(TOI_RO)
+PAGEFLAG_FALSE(TOI_Dirty)
+PAGEFLAG_FALSE(TOI_Untracked)
+PAGEFLAG_FALSE(TOI_CBW)
+#endif
 
 #if defined(CONFIG_IDLE_PAGE_TRACKING) && defined(CONFIG_64BIT)
 TESTPAGEFLAG(Young, young, PF_ANY)
@@ -665,8 +682,12 @@ static inline void ClearPageSlabPfmemalloc(struct page *page)
  * __PG_HWPOISON is exceptional because it needs to be kept beyond page's
  * alloc-free cycle to prevent from reusing the page.
  */
-#define PAGE_FLAGS_CHECK_AT_PREP	\
-	(((1 << NR_PAGEFLAGS) - 1) & ~__PG_HWPOISON)
+#ifdef CONFIG_TOI_INCREMENTAL
+#define PAGE_FLAGS_CHECK_AT_PREP	(((1 << NR_PAGEFLAGS) - 1) & \
+        ~((1 << PG_toi_dirty) | (1 << PG_toi_ro) | ~__PG_HWPOISON))
+#else
+#define PAGE_FLAGS_CHECK_AT_PREP	(((1 << NR_PAGEFLAGS) - 1) & ~__PG_HWPOISON)
+#endif
 
 #define PAGE_FLAGS_PRIVATE				\
 	(1 << PG_private | 1 << PG_private_2)
diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
index 4d4780c00..665cd8591 100644
--- a/include/linux/shmem_fs.h
+++ b/include/linux/shmem_fs.h
@@ -45,9 +45,10 @@ static inline struct shmem_inode_info *SHMEM_I(struct inode *inode)
 extern int shmem_init(void);
 extern int shmem_fill_super(struct super_block *sb, void *data, int silent);
 extern struct file *shmem_file_setup(const char *name,
-					loff_t size, unsigned long flags);
+					loff_t size, unsigned long flags,
+					int atomic_copy);
 extern struct file *shmem_kernel_file_setup(const char *name, loff_t size,
-					    unsigned long flags);
+					    unsigned long flags, int atomic_copy);
 extern int shmem_zero_setup(struct vm_area_struct *);
 extern int shmem_lock(struct file *file, int lock, struct user_struct *user);
 extern bool shmem_mapping(struct address_space *mapping);
diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index 8b6ec7ef0..0e527a70e 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -491,6 +491,74 @@ extern bool pm_print_times_enabled;
 #define pm_print_times_enabled	(false)
 #endif
 
+enum {
+	TOI_CAN_HIBERNATE,
+	TOI_CAN_RESUME,
+	TOI_RESUME_DEVICE_OK,
+	TOI_NORESUME_SPECIFIED,
+	TOI_SANITY_CHECK_PROMPT,
+	TOI_CONTINUE_REQ,
+	TOI_RESUMED_BEFORE,
+	TOI_BOOT_TIME,
+	TOI_NOW_RESUMING,
+	TOI_IGNORE_LOGLEVEL,
+	TOI_TRYING_TO_RESUME,
+	TOI_LOADING_ALT_IMAGE,
+	TOI_STOP_RESUME,
+	TOI_IO_STOPPED,
+	TOI_NOTIFIERS_PREPARE,
+	TOI_CLUSTER_MODE,
+	TOI_BOOT_KERNEL,
+	TOI_DEVICE_HOTPLUG_LOCKED,
+};
+
+#ifdef CONFIG_TOI
+
+/* Used in init dir files */
+extern unsigned long toi_state;
+#define set_toi_state(bit) (set_bit(bit, &toi_state))
+#define clear_toi_state(bit) (clear_bit(bit, &toi_state))
+#define test_toi_state(bit) (test_bit(bit, &toi_state))
+extern int toi_running;
+
+#define test_action_state(bit) (test_bit(bit, &toi_bkd.toi_action))
+extern int try_tuxonice_hibernate(void);
+
+#else /* !CONFIG_TOI */
+
+#define toi_state		(0)
+#define set_toi_state(bit) do { } while (0)
+#define clear_toi_state(bit) do { } while (0)
+#define test_toi_state(bit) (0)
+#define toi_running (0)
+
+static inline int try_tuxonice_hibernate(void) { return 0; }
+#define test_action_state(bit) (0)
+
+#endif /* CONFIG_TOI */
+
+#ifdef CONFIG_HIBERNATION
+#ifdef CONFIG_TOI
+extern void try_tuxonice_resume(void);
+#else
+#define try_tuxonice_resume() do { } while (0)
+#endif
+
+extern int resume_attempted;
+extern int software_resume(void);
+
+static inline void check_resume_attempted(void)
+{
+	if (resume_attempted)
+		return;
+
+	software_resume();
+}
+#else
+#define check_resume_attempted() do { } while (0)
+#define resume_attempted (0)
+#endif
+
 #ifdef CONFIG_PM_AUTOSLEEP
 
 /* kernel/power/autosleep.c */
diff --git a/include/linux/swap.h b/include/linux/swap.h
index d18b65c53..44324f10f 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -288,6 +288,7 @@ static inline void workingset_node_shadows_dec(struct radix_tree_node *node)
 extern unsigned long totalram_pages;
 extern unsigned long totalreserve_pages;
 extern unsigned long nr_free_buffer_pages(void);
+extern unsigned long nr_unallocated_buffer_pages(void);
 extern unsigned long nr_free_pagecache_pages(void);
 
 /* Definition of global_page_state not available yet */
@@ -328,6 +329,8 @@ extern unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *mem,
 						struct zone *zone,
 						unsigned long *nr_scanned);
 extern unsigned long shrink_all_memory(unsigned long nr_pages);
+extern unsigned long shrink_memory_mask(unsigned long nr_to_reclaim,
+		gfp_t mask);
 extern int vm_swappiness;
 extern int remove_mapping(struct address_space *mapping, struct page *page);
 extern unsigned long vm_total_pages;
@@ -413,14 +416,18 @@ extern void swapcache_free(swp_entry_t);
 extern int free_swap_and_cache(swp_entry_t);
 extern int swap_type_of(dev_t, sector_t, struct block_device **);
 extern unsigned int count_swap_pages(int, int);
+extern sector_t map_swap_entry(swp_entry_t entry, struct block_device **);
 extern sector_t map_swap_page(struct page *, struct block_device **);
 extern sector_t swapdev_block(int, pgoff_t);
+extern struct swap_info_struct *get_swap_info_struct(unsigned);
 extern int page_swapcount(struct page *);
 extern int swp_swapcount(swp_entry_t entry);
 extern struct swap_info_struct *page_swap_info(struct page *);
 extern int reuse_swap_page(struct page *);
 extern int try_to_free_swap(struct page *);
 struct backing_dev_info;
+extern void get_swap_range_of_type(int type, swp_entry_t *start,
+		swp_entry_t *end, unsigned int limit);
 
 #else /* CONFIG_SWAP */
 
diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h
index b4c2a485b..c54e16a5d 100644
--- a/include/linux/thread_info.h
+++ b/include/linux/thread_info.h
@@ -56,10 +56,10 @@ extern long do_no_restart_syscall(struct restart_block *parm);
 #ifdef __KERNEL__
 
 #ifdef CONFIG_DEBUG_STACK_USAGE
-# define THREADINFO_GFP		(GFP_KERNEL_ACCOUNT | __GFP_NOTRACK | \
+# define THREADINFO_GFP		(GFP_KERNEL_ACCOUNT | __GFP_NOTRACK | ___GFP_TOI_NOTRACK | \
 				 __GFP_ZERO)
 #else
-# define THREADINFO_GFP		(GFP_KERNEL_ACCOUNT | __GFP_NOTRACK)
+# define THREADINFO_GFP		(GFP_KERNEL_ACCOUNT | __GFP_NOTRACK | ___GFP_TOI_NOTRACK)
 #endif
 
 /*
diff --git a/include/linux/tuxonice.h b/include/linux/tuxonice.h
new file mode 100644
index 000000000..67b05a750
--- /dev/null
+++ b/include/linux/tuxonice.h
@@ -0,0 +1,48 @@
+/*
+ * include/linux/tuxonice.h
+ *
+ * Copyright (C) 2015 Nigel Cunningham (nigel at tuxonice net)
+ *
+ * This file is released under the GPLv2.
+ */
+
+#ifndef INCLUDE_LINUX_TUXONICE_H
+#define INCLUDE_LINUX_TUXONICE_H
+#ifdef CONFIG_TOI_INCREMENTAL
+extern void toi_set_logbuf_untracked(void);
+extern int toi_make_writable(pgd_t *pgd, unsigned long address);
+
+static inline int toi_incremental_support(void)
+{
+    return 1;
+}
+
+/* Copy Before Write */
+struct toi_cbw {
+    unsigned long pfn;
+    void *virt;
+    struct toi_cbw *next;
+};
+
+struct toi_cbw_state {
+    bool active;            /* Is a fault handler running? */
+    bool enabled;           /* Are we doing copy before write? */
+    int size;               /* The number of pages allocated */
+    struct toi_cbw *first, *next, *last;  /* Pointers to the data structure */
+};
+
+#define CBWS_PER_PAGE (PAGE_SIZE / sizeof(struct toi_cbw))
+DECLARE_PER_CPU(struct toi_cbw_state, toi_cbw_states);
+#else
+#define toi_set_logbuf_untracked() do { } while(0)
+static inline int toi_make_writable(pgd_t *pgd, unsigned long addr)
+{
+    return 0;
+}
+
+static inline int toi_incremental_support(void)
+{
+    return 0;
+}
+#endif
+#endif
diff --git a/include/uapi/linux/netlink.h b/include/uapi/linux/netlink.h
index f095155d8..f95de72f5 100644
--- a/include/uapi/linux/netlink.h
+++ b/include/uapi/linux/netlink.h
@@ -27,6 +27,8 @@
 #define NETLINK_ECRYPTFS	19
 #define NETLINK_RDMA		20
 #define NETLINK_CRYPTO		21	/* Crypto layer */
+#define NETLINK_TOI_USERUI	22	/* TuxOnIce's userui */
+#define NETLINK_TOI_USM		23	/* Userspace storage manager */
 
 #define NETLINK_INET_DIAG	NETLINK_SOCK_DIAG
 
diff --git a/init/do_mounts.c b/init/do_mounts.c
index dea5de95c..1fed72621 100644
--- a/init/do_mounts.c
+++ b/init/do_mounts.c
@@ -597,6 +597,8 @@ void __init prepare_namespace(void)
 	if (is_floppy && rd_doload && rd_load_disk(0))
 		ROOT_DEV = Root_RAM0;
 
+	check_resume_attempted();
+
 	mount_root();
 out:
 	devtmpfs_mount("dev");
diff --git a/init/do_mounts_initrd.c b/init/do_mounts_initrd.c
index a1000ca29..56b5a0c8a 100644
--- a/init/do_mounts_initrd.c
+++ b/init/do_mounts_initrd.c
@@ -15,6 +15,7 @@
 #include <linux/romfs_fs.h>
 #include <linux/initrd.h>
 #include <linux/sched.h>
+#include <linux/suspend.h>
 #include <linux/freezer.h>
 #include <linux/kmod.h>
 
@@ -79,6 +80,11 @@ static void __init handle_initrd(void)
 
 	current->flags &= ~PF_FREEZER_SKIP;
 
+	if (!resume_attempted)
+		printk(KERN_ERR "TuxOnIce: No attempt was made to resume from "
+				"any image that might exist.\n");
+	clear_toi_state(TOI_BOOT_TIME);
+
 	/* move initrd to rootfs' /old */
 	sys_mount("..", ".", NULL, MS_MOVE, NULL);
 	/* switch root and cwd back to / of rootfs */
diff --git a/ipc/shm.c b/ipc/shm.c
index 331fc1b0b..12934ca3a 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -578,7 +578,7 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
 		if  ((shmflg & SHM_NORESERVE) &&
 				sysctl_overcommit_memory != OVERCOMMIT_NEVER)
 			acctflag = VM_NORESERVE;
-		file = shmem_kernel_file_setup(name, size, acctflag);
+		file = shmem_kernel_file_setup(name, size, acctflag, 0);
 	}
 	error = PTR_ERR(file);
 	if (IS_ERR(file))
diff --git a/kernel/fork.c b/kernel/fork.c
index 2e391c754..bb061d0ea 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -138,7 +138,7 @@ static struct kmem_cache *task_struct_cachep;
 
 static inline struct task_struct *alloc_task_struct_node(int node)
 {
-	return kmem_cache_alloc_node(task_struct_cachep, GFP_KERNEL, node);
+	return kmem_cache_alloc_node(task_struct_cachep, GFP_KERNEL | ___GFP_TOI_NOTRACK, node);
 }
 
 static inline void free_task_struct(struct task_struct *tsk)
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 9ff173dca..12d8a8f88 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -275,7 +275,7 @@ struct task_struct *kthread_create_on_node(int (*threadfn)(void *data),
 	DECLARE_COMPLETION_ONSTACK(done);
 	struct task_struct *task;
 	struct kthread_create_info *create = kmalloc(sizeof(*create),
-						     GFP_KERNEL);
+						     GFP_KERNEL | ___GFP_TOI_NOTRACK);
 
 	if (!create)
 		return ERR_PTR(-ENOMEM);
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index 68d3ebc12..5f93a3ccd 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -101,6 +101,284 @@ config PM_STD_PARTITION
 	  suspended image to. It will simply pick the first available swap 
 	  device.
 
+menuconfig TOI_CORE
+	bool "Enhanced Hibernation (TuxOnIce)"
+	depends on HIBERNATION
+	default y
+	---help---
+	  TuxOnIce is the 'new and improved' suspend support.
+
+	  See the TuxOnIce home page (tuxonice.net)
+	  for FAQs, HOWTOs and other documentation.
+
+	comment "Image Storage (you need at least one allocator)"
+		depends on TOI_CORE
+
+	config TOI_FILE
+		bool "File Allocator"
+		depends on TOI_CORE
+		default y
+		---help---
+		  This option enables support for storing an image in a
+		  simple file. You might want this if your swap is
+		  sometimes full enough that you don't have enough spare
+		  space to store an image.
+
+	config TOI_SWAP
+		bool "Swap Allocator"
+		depends on TOI_CORE && SWAP
+		default y
+		---help---
+		  This option enables support for storing an image in your
+		  swap space.
+
+	comment "General Options"
+		depends on TOI_CORE
+
+	config TOI_PRUNE
+		bool "Image pruning support"
+		depends on TOI_CORE && CRYPTO && BROKEN
+		default y
+		---help---
+		  This option adds support for using cryptoapi hashing
+		  algorithms to identify pages with the same content. We
+		  then write a much smaller pointer to the first copy of
+		  the data instead of a complete (perhaps compressed)
+                  additional copy.
+
+		  You probably want this, so say Y here.
+
+	comment "No image pruning support available without Cryptoapi support."
+		depends on TOI_CORE && !CRYPTO
+
+	config TOI_CRYPTO
+		bool "Compression support"
+		depends on TOI_CORE && CRYPTO
+		default y
+		---help---
+		  This option adds support for using cryptoapi compression
+		  algorithms. Compression is particularly useful as it can
+		  more than double your suspend and resume speed (depending
+		  upon how well your image compresses).
+
+		  You probably want this, so say Y here.
+
+	comment "No compression support available without Cryptoapi support."
+		depends on TOI_CORE && !CRYPTO
+
+	config TOI_USERUI
+		bool "Userspace User Interface support"
+		depends on TOI_CORE && NET && (VT || SERIAL_CONSOLE)
+		default y
+		---help---
+		  This option enabled support for a userspace based user interface
+		  to TuxOnIce, which allows you to have a nice display while suspending
+		  and resuming, and also enables features such as pressing escape to
+		  cancel a cycle or interactive debugging.
+
+	config TOI_USERUI_DEFAULT_PATH
+		string "Default userui program location"
+		default "/usr/local/sbin/tuxoniceui_text"
+		depends on TOI_USERUI
+		---help---
+		  This entry allows you to specify a default path to the userui binary.
+
+	config TOI_DEFAULT_IMAGE_SIZE_LIMIT
+		int "Default image size limit"
+		range -2 65536 
+		default "-2"
+		depends on TOI_CORE
+		---help---
+		  This entry allows you to specify a default image size limit. It can
+		  be overridden at run-time using /sys/power/tuxonice/image_size_limit.
+
+	config TOI_KEEP_IMAGE
+		bool "Allow Keep Image Mode"
+		depends on TOI_CORE
+		---help---
+		  This option allows you to keep and image and reuse it. It is intended
+		  __ONLY__ for use with systems where all filesystems are mounted read-
+		  only (kiosks, for example). To use it, compile this option in and boot
+		  normally. Set the KEEP_IMAGE flag in /sys/power/tuxonice and suspend.
+		  When you resume, the image will not be removed. You will be unable to turn
+		  off swap partitions (assuming you are using the swap allocator), but future
+		  suspends simply do a power-down. The image can be updated using the
+		  kernel command line parameter suspend_act= to turn off the keep image
+		  bit. Keep image mode is a little less user friendly on purpose - it
+		  should not be used without thought!
+
+	config TOI_INCREMENTAL
+		bool "Incremental Image Support"
+		depends on TOI_CORE && 64BIT && TOI_KEEP_IMAGE
+		default n
+		---help---
+		  This option enables the work in progress toward using the dirty page
+		  tracking to record changes to pages. It is hoped that
+		  this will be an initial step toward implementing storing just
+		  the differences between consecutive images, which will
+		  increase the amount of storage needed for the image, but also
+		  increase the speed at which writing an image occurs and
+		  reduce the wear and tear on drives.
+
+		  At the moment, all that is implemented is the first step of keeping
+		  an existing image and then comparing it to the contents in memory
+		  (by setting /sys/power/tuxonice/verify_image to 1 and triggering a
+		  (fake) resume) to see what the page change tracking should find to be
+		  different. If you have verify_image set to 1, TuxOnIce will automatically
+		  invalidate the old image when you next try to hibernate, so there's no
+		  greater chance of disk corruption than normal.
+
+	comment "No incremental image support available without Keep Image support."
+		depends on TOI_CORE && !TOI_KEEP_IMAGE && 64BIT
+
+	config TOI_REPLACE_SWSUSP
+		bool "Replace swsusp by default"
+		default y
+		depends on TOI_CORE
+		---help---
+		  TuxOnIce can replace swsusp. This option makes that the default state,
+		  requiring you to echo 0 > /sys/power/tuxonice/replace_swsusp if you want
+		  to use the vanilla kernel functionality. Note that your initrd/ramfs will
+		  need to do this before trying to resume, too.
+		  With overriding swsusp enabled, echoing disk  to /sys/power/state will
+		  start a TuxOnIce cycle. If resume= doesn't specify an allocator and both
+		  the swap and file allocators are compiled in, the swap allocator will be
+		  used by default.
+
+	config TOI_IGNORE_LATE_INITCALL
+		bool "Wait for initrd/ramfs to run, by default"
+		default n
+		depends on TOI_CORE
+		---help---
+		  When booting, TuxOnIce can check for an image and start to resume prior
+		  to any initrd/ramfs running (via a late initcall).
+
+		  If you don't have an initrd/ramfs, this is what you want to happen -
+		  otherwise you won't be able to safely resume. You should set this option
+		  to 'No'.
+
+		  If, however, you want your initrd/ramfs to run anyway before resuming,
+		  you need to tell TuxOnIce to ignore that earlier opportunity to resume.
+		  This can be done either by using this compile time option, or by
+		  overriding this option with the boot-time parameter toi_initramfs_resume_only=1.
+
+		  Note that if TuxOnIce can't resume at the earlier opportunity, the
+		  value of this option won't matter - the initramfs/initrd (if any) will
+		  run anyway.
+
+	menuconfig TOI_CLUSTER
+		bool "Cluster support"
+		default n
+		depends on TOI_CORE && NET && BROKEN
+		---help---
+		  Support for linking multiple machines in a cluster so that they suspend
+		  and resume together.
+
+	config TOI_DEFAULT_CLUSTER_INTERFACE
+		string "Default cluster interface"
+		depends on TOI_CLUSTER
+		---help---
+		  The default interface on which to communicate with other nodes in
+		  the cluster.
+
+		  If no value is set here, cluster support will be disabled by default.
+
+	config TOI_DEFAULT_CLUSTER_KEY
+		string "Default cluster key"
+		default "Default"
+		depends on TOI_CLUSTER
+		---help---
+		  The default key used by this node. All nodes in the same cluster
+		  have the same key. Multiple clusters may coexist on the same lan
+		  by using different values for this key.
+
+	config TOI_CLUSTER_IMAGE_TIMEOUT
+		int "Timeout when checking for image"
+		default 15
+		depends on TOI_CLUSTER
+		---help---
+		  Timeout (seconds) before continuing to boot when waiting to see
+		  whether other nodes might have an image. Set to -1 to wait
+		  indefinitely. In WAIT_UNTIL_NODES is non zero, we might continue
+		  booting sooner than this timeout.
+
+	config TOI_CLUSTER_WAIT_UNTIL_NODES
+		int "Nodes without image before continuing"
+		default 0
+		depends on TOI_CLUSTER
+		---help---
+		  When booting and no image is found, we wait to see if other nodes
+		  have an image before continuing to boot. This value lets us
+		  continue after seeing a certain number of nodes without an image,
+		  instead of continuing to wait for the timeout. Set to 0 to only
+		  use the timeout.
+
+	config TOI_DEFAULT_CLUSTER_PRE_HIBERNATE
+		string "Default pre-hibernate script"
+		depends on TOI_CLUSTER
+		---help---
+		  The default script to be called when starting to hibernate.
+
+	config TOI_DEFAULT_CLUSTER_POST_HIBERNATE
+		string "Default post-hibernate script"
+		depends on TOI_CLUSTER
+		---help---
+		  The default script to be called after resuming from hibernation.
+
+	config TOI_DEFAULT_WAIT
+		int "Default waiting time for emergency boot messages"
+		default "25"
+		range -1 32768
+		depends on TOI_CORE
+		help
+		  TuxOnIce can display warnings very early in the process of resuming,
+		  if (for example) it appears that you have booted a kernel that doesn't
+		  match an image on disk. It can then give you the opportunity to either
+		  continue booting that kernel, or reboot the machine. This option can be
+		  used to control how long to wait in such circumstances. -1 means wait
+		  forever. 0 means don't wait at all (do the default action, which will
+		  generally be to continue booting and remove the image). Values of 1 or
+		  more indicate a number of seconds (up to 255) to wait before doing the
+		  default.
+
+	config  TOI_DEFAULT_EXTRA_PAGES_ALLOWANCE
+		int "Default extra pages allowance"
+		default "2000"
+		range 500 32768
+		depends on TOI_CORE
+		help
+		  This value controls the default for the allowance TuxOnIce makes for
+		  drivers to allocate extra memory during the atomic copy. The default
+		  value of 2000 will be okay in most cases. If you are using
+		  DRI, the easiest way to find what value to use is to try to hibernate
+		  and look at how many pages were actually needed in the sysfs entry
+		  /sys/power/tuxonice/debug_info (first number on the last line), adding
+		  a little extra because the value is not always the same.
+
+	config TOI_CHECKSUM
+		bool "Checksum pageset2"
+		default n
+		depends on TOI_CORE
+		select CRYPTO
+		select CRYPTO_ALGAPI
+		select CRYPTO_MD4
+		---help---
+		  Adds support for checksumming pageset2 pages, to ensure you really get an
+		  atomic copy. Since some filesystems (XFS especially) change metadata even
+		  when there's no other activity, we need this to check for pages that have
+		  been changed while we were saving the page cache. If your debugging output
+		  always says no pages were resaved, you may be able to safely disable this
+		  option.
+
+config TOI
+	bool
+	depends on TOI_CORE!=n
+	default y
+
+config TOI_ZRAM_SUPPORT
+	def_bool y
+	depends on TOI && ZRAM!=n
+
 config PM_SLEEP
 	def_bool y
 	depends on SUSPEND || HIBERNATE_CALLBACKS
diff --git a/kernel/power/Makefile b/kernel/power/Makefile
index cb880a14c..82c4795e8 100644
--- a/kernel/power/Makefile
+++ b/kernel/power/Makefile
@@ -1,6 +1,38 @@
 
 ccflags-$(CONFIG_PM_DEBUG)	:= -DDEBUG
 
+tuxonice_core-y := tuxonice_modules.o
+
+obj-$(CONFIG_TOI)		+= tuxonice_builtin.o
+obj-$(CONFIG_TOI_INCREMENTAL)   += tuxonice_incremental.o \
+    tuxonice_copy_before_write.o
+
+tuxonice_core-$(CONFIG_PM_DEBUG)	+= tuxonice_alloc.o
+
+# Compile these in after allocation debugging, if used.
+
+tuxonice_core-y += tuxonice_sysfs.o tuxonice_highlevel.o \
+		tuxonice_io.o tuxonice_pagedir.o tuxonice_prepare_image.o \
+		tuxonice_extent.o tuxonice_pageflags.o tuxonice_ui.o \
+		tuxonice_power_off.o tuxonice_atomic_copy.o
+
+tuxonice_core-$(CONFIG_TOI_CHECKSUM)	+= tuxonice_checksum.o
+
+tuxonice_core-$(CONFIG_NET)	+= tuxonice_storage.o tuxonice_netlink.o
+
+obj-$(CONFIG_TOI_CORE)		+= tuxonice_core.o
+obj-$(CONFIG_TOI_PRUNE)		+= tuxonice_prune.o
+obj-$(CONFIG_TOI_CRYPTO)	+= tuxonice_compress.o
+
+tuxonice_bio-y := tuxonice_bio_core.o tuxonice_bio_chains.o \
+		tuxonice_bio_signature.o
+
+obj-$(CONFIG_TOI_SWAP)		+= tuxonice_bio.o tuxonice_swap.o
+obj-$(CONFIG_TOI_FILE)		+= tuxonice_bio.o tuxonice_file.o
+obj-$(CONFIG_TOI_CLUSTER)	+= tuxonice_cluster.o
+
+obj-$(CONFIG_TOI_USERUI)	+= tuxonice_userui.o
+
 obj-y				+= qos.o
 obj-$(CONFIG_PM)		+= main.o
 obj-$(CONFIG_VT_CONSOLE_SLEEP)	+= console.o
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index b7342a24f..153e51db5 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -31,7 +31,7 @@
 #include <linux/ktime.h>
 #include <trace/events/power.h>
 
-#include "power.h"
+#include "tuxonice.h"
 
 
 static int nocompress;
@@ -39,7 +39,7 @@ static int noresume;
 static int nohibernate;
 static int resume_wait;
 static unsigned int resume_delay;
-static char resume_file[256] = CONFIG_PM_STD_PARTITION;
+char resume_file[256] = CONFIG_PM_STD_PARTITION;
 dev_t swsusp_resume_device;
 sector_t swsusp_resume_block;
 __visible int in_suspend __nosavedata;
@@ -123,7 +123,7 @@ static int hibernation_test(int level) { return 0; }
  * platform_begin - Call platform to start hibernation.
  * @platform_mode: Whether or not to use the platform driver.
  */
-static int platform_begin(int platform_mode)
+int platform_begin(int platform_mode)
 {
 	return (platform_mode && hibernation_ops) ?
 		hibernation_ops->begin() : 0;
@@ -133,7 +133,7 @@ static int platform_begin(int platform_mode)
  * platform_end - Call platform to finish transition to the working state.
  * @platform_mode: Whether or not to use the platform driver.
  */
-static void platform_end(int platform_mode)
+void platform_end(int platform_mode)
 {
 	if (platform_mode && hibernation_ops)
 		hibernation_ops->end();
@@ -147,7 +147,7 @@ static void platform_end(int platform_mode)
  * if so configured, and return an error code if that fails.
  */
 
-static int platform_pre_snapshot(int platform_mode)
+int platform_pre_snapshot(int platform_mode)
 {
 	return (platform_mode && hibernation_ops) ?
 		hibernation_ops->pre_snapshot() : 0;
@@ -162,7 +162,7 @@ static int platform_pre_snapshot(int platform_mode)
  *
  * This routine is called on one CPU with interrupts disabled.
  */
-static void platform_leave(int platform_mode)
+void platform_leave(int platform_mode)
 {
 	if (platform_mode && hibernation_ops)
 		hibernation_ops->leave();
@@ -177,7 +177,7 @@ static void platform_leave(int platform_mode)
  *
  * This routine must be called after platform_prepare().
  */
-static void platform_finish(int platform_mode)
+void platform_finish(int platform_mode)
 {
 	if (platform_mode && hibernation_ops)
 		hibernation_ops->finish();
@@ -193,7 +193,7 @@ static void platform_finish(int platform_mode)
  * If the restore fails after this function has been called,
  * platform_restore_cleanup() must be called.
  */
-static int platform_pre_restore(int platform_mode)
+int platform_pre_restore(int platform_mode)
 {
 	return (platform_mode && hibernation_ops) ?
 		hibernation_ops->pre_restore() : 0;
@@ -210,7 +210,7 @@ static int platform_pre_restore(int platform_mode)
  * function must be called too, regardless of the result of
  * platform_pre_restore().
  */
-static void platform_restore_cleanup(int platform_mode)
+void platform_restore_cleanup(int platform_mode)
 {
 	if (platform_mode && hibernation_ops)
 		hibernation_ops->restore_cleanup();
@@ -220,7 +220,7 @@ static void platform_restore_cleanup(int platform_mode)
  * platform_recover - Recover from a failure to suspend devices.
  * @platform_mode: Whether or not to use the platform driver.
  */
-static void platform_recover(int platform_mode)
+void platform_recover(int platform_mode)
 {
 	if (platform_mode && hibernation_ops && hibernation_ops->recover)
 		hibernation_ops->recover();
@@ -648,6 +648,9 @@ int hibernate(void)
 {
 	int error;
 
+	if (test_action_state(TOI_REPLACE_SWSUSP))
+		return try_tuxonice_hibernate();
+
 	if (!hibernation_available()) {
 		pr_debug("PM: Hibernation not available.\n");
 		return -EPERM;
@@ -737,11 +740,19 @@ int hibernate(void)
  * attempts to recover gracefully and make the kernel return to the normal mode
  * of operation.
  */
-static int software_resume(void)
+int software_resume(void)
 {
 	int error;
 	unsigned int flags;
 
+	resume_attempted = 1;
+
+	/*
+	 * We can't know (until an image header - if any - is loaded), whether
+	 * we did override swsusp. We therefore ensure that both are tried.
+	 */
+	try_tuxonice_resume();
+
 	/*
 	 * If the user said "noresume".. bail out early.
 	 */
@@ -1128,6 +1139,7 @@ static int __init hibernate_setup(char *str)
 static int __init noresume_setup(char *str)
 {
 	noresume = 1;
+	set_toi_state(TOI_NORESUME_SPECIFIED);
 	return 1;
 }
 
diff --git a/kernel/power/power.h b/kernel/power/power.h
index efe1b3b17..2577c6d01 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -36,8 +36,12 @@ static inline char *check_image_kernel(struct swsusp_info *info)
 	return arch_hibernation_header_restore(info) ?
 			"architecture specific data" : NULL;
 }
+#else
+extern char *check_image_kernel(struct swsusp_info *info);
 #endif /* CONFIG_ARCH_HIBERNATION_HEADER */
+extern int init_header(struct swsusp_info *info);
 
+extern char resume_file[256];
 /*
  * Keep some memory free so that I/O operations can succeed without paging
  * [Might this be more than 4 MB?]
@@ -86,6 +90,8 @@ static struct kobj_attribute _name##_attr = {	\
 	.show	= _name##_show,			\
 }
 
+extern struct pbe *restore_pblist;
+
 /* Preferred image size in bytes (default 500 MB) */
 extern unsigned long image_size;
 /* Size of memory reserved for drivers (default SPARE_PAGES x PAGE_SIZE) */
@@ -269,6 +275,31 @@ static inline void suspend_thaw_processes(void)
 }
 #endif
 
+extern struct page *saveable_page(struct zone *z, unsigned long p);
+#ifdef CONFIG_HIGHMEM
+struct page *saveable_highmem_page(struct zone *z, unsigned long p);
+#else
+static
+inline void *saveable_highmem_page(struct zone *z, unsigned long p)
+{
+	return NULL;
+}
+#endif
+
+#define PBES_PER_PAGE (PAGE_SIZE / sizeof(struct pbe))
+extern struct list_head nosave_regions;
+
+/**
+ *	This structure represents a range of page frames the contents of which
+ *	should not be saved during the suspend.
+ */
+
+struct nosave_region {
+	struct list_head list;
+	unsigned long start_pfn;
+	unsigned long end_pfn;
+};
+
 #ifdef CONFIG_PM_AUTOSLEEP
 
 /* kernel/power/autosleep.c */
@@ -295,3 +326,10 @@ extern int pm_wake_lock(const char *buf);
 extern int pm_wake_unlock(const char *buf);
 
 #endif /* !CONFIG_PM_WAKELOCKS */
+
+#ifdef CONFIG_TOI
+unsigned long toi_get_nonconflicting_page(void);
+#define BM_END_OF_MAP	(~0UL)
+#else
+#define toi_get_nonconflicting_page() (0)
+#endif
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 3a9706043..542163a01 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -36,6 +36,9 @@
 #include <asm/tlbflush.h>
 #include <asm/io.h>
 
+#include "tuxonice_modules.h"
+#include "tuxonice_builtin.h"
+#include "tuxonice_alloc.h"
 #include "power.h"
 
 static int swsusp_page_is_free(struct page *);
@@ -98,6 +101,9 @@ static void *get_image_page(gfp_t gfp_mask, int safe_needed)
 {
 	void *res;
 
+        if (toi_running)
+            return (void *) toi_get_nonconflicting_page();
+
 	res = (void *)get_zeroed_page(gfp_mask);
 	if (safe_needed)
 		while (res && swsusp_page_is_free(virt_to_page(res))) {
@@ -143,6 +149,11 @@ static inline void free_image_page(void *addr, int clear_nosave_free)
 
 	page = virt_to_page(addr);
 
+        if (toi_running) {
+            toi__free_page(29, page);
+            return;
+        }
+
 	swsusp_unset_page_forbidden(page);
 	if (clear_nosave_free)
 		swsusp_unset_page_free(page);
@@ -302,13 +313,15 @@ struct bm_position {
 	int node_bit;
 };
 
+#define BM_POSITION_SLOTS (NR_CPUS * 2)
+
 struct memory_bitmap {
 	struct list_head zones;
 	struct linked_page *p_list;	/* list of pages used to store zone
 					 * bitmap objects and bitmap block
 					 * objects
 					 */
-	struct bm_position cur;	/* most recently used bit position */
+	struct bm_position cur[BM_POSITION_SLOTS];    /* most recently used bit position */
 };
 
 /* Functions that operate on memory bitmaps */
@@ -473,16 +486,39 @@ static void free_zone_bm_rtree(struct mem_zone_bm_rtree *zone,
 		free_image_page(node->data, clear_nosave_free);
 }
 
-static void memory_bm_position_reset(struct memory_bitmap *bm)
+void memory_bm_position_reset(struct memory_bitmap *bm)
 {
-	bm->cur.zone = list_entry(bm->zones.next, struct mem_zone_bm_rtree,
+    int index;
+
+    for (index = 0; index < BM_POSITION_SLOTS; index++) {
+	bm->cur[index].zone = list_entry(bm->zones.next, struct mem_zone_bm_rtree,
 				  list);
-	bm->cur.node = list_entry(bm->cur.zone->leaves.next,
+	bm->cur[index].node = list_entry(bm->cur[index].zone->leaves.next,
 				  struct rtree_node, list);
-	bm->cur.node_pfn = 0;
-	bm->cur.node_bit = 0;
+	bm->cur[index].node_pfn = 0;
+	bm->cur[index].node_bit = 0;
+    }
 }
 
+static void memory_bm_clear_current(struct memory_bitmap *bm, int index);
+unsigned long memory_bm_next_pfn(struct memory_bitmap *bm, int index);
+
+/**
+ *      memory_bm_clear
+ *      @param bm - The bitmap to clear
+ *
+ *      Only run while single threaded - locking not needed
+ */
+void memory_bm_clear(struct memory_bitmap *bm)
+{
+    memory_bm_position_reset(bm);
+
+    while (memory_bm_next_pfn(bm, 0) != BM_END_OF_MAP) {
+        memory_bm_clear_current(bm, 0);
+    }
+
+    memory_bm_position_reset(bm);
+}
 static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free);
 
 struct mem_extent {
@@ -595,7 +631,8 @@ memory_bm_create(struct memory_bitmap *bm, gfp_t gfp_mask, int safe_needed)
 	}
 
 	bm->p_list = ca.chain;
-	memory_bm_position_reset(bm);
+
+        memory_bm_position_reset(bm);
  Exit:
 	free_mem_extents(&mem_extents);
 	return error;
@@ -631,14 +668,24 @@ static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free)
  *	It walks the radix tree to find the page which contains the bit for
  *	pfn and returns the bit position in **addr and *bit_nr.
  */
-static int memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
-			      void **addr, unsigned int *bit_nr)
+int memory_bm_find_bit(struct memory_bitmap *bm, int index,
+        unsigned long pfn, void **addr, unsigned int *bit_nr)
 {
 	struct mem_zone_bm_rtree *curr, *zone;
 	struct rtree_node *node;
 	int i, block_nr;
 
-	zone = bm->cur.zone;
+        if (!bm->cur[index].zone) {
+            // Reset
+            bm->cur[index].zone = list_entry(bm->zones.next, struct mem_zone_bm_rtree,
+                    list);
+            bm->cur[index].node = list_entry(bm->cur[index].zone->leaves.next,
+                    struct rtree_node, list);
+            bm->cur[index].node_pfn = 0;
+            bm->cur[index].node_bit = 0;
+        }
+
+	zone = bm->cur[index].zone;
 
 	if (pfn >= zone->start_pfn && pfn < zone->end_pfn)
 		goto zone_found;
@@ -662,8 +709,8 @@ zone_found:
 	 * node for our pfn.
 	 */
 
-	node = bm->cur.node;
-	if (((pfn - zone->start_pfn) & ~BM_BLOCK_MASK) == bm->cur.node_pfn)
+	node = bm->cur[index].node;
+	if (((pfn - zone->start_pfn) & ~BM_BLOCK_MASK) == bm->cur[index].node_pfn)
 		goto node_found;
 
 	node      = zone->rtree;
@@ -680,9 +727,9 @@ zone_found:
 
 node_found:
 	/* Update last position */
-	bm->cur.zone = zone;
-	bm->cur.node = node;
-	bm->cur.node_pfn = (pfn - zone->start_pfn) & ~BM_BLOCK_MASK;
+	bm->cur[index].zone = zone;
+	bm->cur[index].node = node;
+	bm->cur[index].node_pfn = (pfn - zone->start_pfn) & ~BM_BLOCK_MASK;
 
 	/* Set return values */
 	*addr = node->data;
@@ -691,66 +738,66 @@ node_found:
 	return 0;
 }
 
-static void memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn)
+void memory_bm_set_bit(struct memory_bitmap *bm, int index, unsigned long pfn)
 {
 	void *addr;
 	unsigned int bit;
 	int error;
 
-	error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+	error = memory_bm_find_bit(bm, index, pfn, &addr, &bit);
 	BUG_ON(error);
 	set_bit(bit, addr);
 }
 
-static int mem_bm_set_bit_check(struct memory_bitmap *bm, unsigned long pfn)
+int mem_bm_set_bit_check(struct memory_bitmap *bm, int index, unsigned long pfn)
 {
 	void *addr;
 	unsigned int bit;
 	int error;
 
-	error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+	error = memory_bm_find_bit(bm, index, pfn, &addr, &bit);
 	if (!error)
 		set_bit(bit, addr);
 
 	return error;
 }
 
-static void memory_bm_clear_bit(struct memory_bitmap *bm, unsigned long pfn)
+void memory_bm_clear_bit(struct memory_bitmap *bm, int index, unsigned long pfn)
 {
 	void *addr;
 	unsigned int bit;
 	int error;
 
-	error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+	error = memory_bm_find_bit(bm, index, pfn, &addr, &bit);
 	BUG_ON(error);
 	clear_bit(bit, addr);
 }
 
-static void memory_bm_clear_current(struct memory_bitmap *bm)
+static void memory_bm_clear_current(struct memory_bitmap *bm, int index)
 {
 	int bit;
 
-	bit = max(bm->cur.node_bit - 1, 0);
-	clear_bit(bit, bm->cur.node->data);
+	bit = max(bm->cur[index].node_bit - 1, 0);
+	clear_bit(bit, bm->cur[index].node->data);
 }
 
-static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn)
+int memory_bm_test_bit(struct memory_bitmap *bm, int index, unsigned long pfn)
 {
 	void *addr;
 	unsigned int bit;
 	int error;
 
-	error = memory_bm_find_bit(bm, pfn, &addr, &bit);
+	error = memory_bm_find_bit(bm, index, pfn, &addr, &bit);
 	BUG_ON(error);
 	return test_bit(bit, addr);
 }
 
-static bool memory_bm_pfn_present(struct memory_bitmap *bm, unsigned long pfn)
+static bool memory_bm_pfn_present(struct memory_bitmap *bm, int index, unsigned long pfn)
 {
 	void *addr;
 	unsigned int bit;
 
-	return !memory_bm_find_bit(bm, pfn, &addr, &bit);
+	return !memory_bm_find_bit(bm, index, pfn, &addr, &bit);
 }
 
 /*
@@ -763,25 +810,25 @@ static bool memory_bm_pfn_present(struct memory_bitmap *bm, unsigned long pfn)
  *
  *	Returns true if there is a next node, false otherwise.
  */
-static bool rtree_next_node(struct memory_bitmap *bm)
+static bool rtree_next_node(struct memory_bitmap *bm, int index)
 {
-	bm->cur.node = list_entry(bm->cur.node->list.next,
+	bm->cur[index].node = list_entry(bm->cur[index].node->list.next,
 				  struct rtree_node, list);
-	if (&bm->cur.node->list != &bm->cur.zone->leaves) {
-		bm->cur.node_pfn += BM_BITS_PER_BLOCK;
-		bm->cur.node_bit  = 0;
+	if (&bm->cur[index].node->list != &bm->cur[index].zone->leaves) {
+		bm->cur[index].node_pfn += BM_BITS_PER_BLOCK;
+		bm->cur[index].node_bit  = 0;
 		touch_softlockup_watchdog();
 		return true;
 	}
 
 	/* No more nodes, goto next zone */
-	bm->cur.zone = list_entry(bm->cur.zone->list.next,
+	bm->cur[index].zone = list_entry(bm->cur[index].zone->list.next,
 				  struct mem_zone_bm_rtree, list);
-	if (&bm->cur.zone->list != &bm->zones) {
-		bm->cur.node = list_entry(bm->cur.zone->leaves.next,
+	if (&bm->cur[index].zone->list != &bm->zones) {
+		bm->cur[index].node = list_entry(bm->cur[index].zone->leaves.next,
 					  struct rtree_node, list);
-		bm->cur.node_pfn = 0;
-		bm->cur.node_bit = 0;
+		bm->cur[index].node_pfn = 0;
+		bm->cur[index].node_bit = 0;
 		return true;
 	}
 
@@ -799,38 +846,29 @@ static bool rtree_next_node(struct memory_bitmap *bm)
  *	It is required to run memory_bm_position_reset() before the
  *	first call to this function.
  */
-static unsigned long memory_bm_next_pfn(struct memory_bitmap *bm)
+unsigned long memory_bm_next_pfn(struct memory_bitmap *bm, int index)
 {
 	unsigned long bits, pfn, pages;
 	int bit;
 
+        index += NR_CPUS; /* Iteration state is separated from get/set/test */
+
 	do {
-		pages	  = bm->cur.zone->end_pfn - bm->cur.zone->start_pfn;
-		bits      = min(pages - bm->cur.node_pfn, BM_BITS_PER_BLOCK);
-		bit	  = find_next_bit(bm->cur.node->data, bits,
-					  bm->cur.node_bit);
+		pages	  = bm->cur[index].zone->end_pfn - bm->cur[index].zone->start_pfn;
+		bits      = min(pages - bm->cur[index].node_pfn, BM_BITS_PER_BLOCK);
+		bit	  = find_next_bit(bm->cur[index].node->data, bits,
+					  bm->cur[index].node_bit);
 		if (bit < bits) {
-			pfn = bm->cur.zone->start_pfn + bm->cur.node_pfn + bit;
-			bm->cur.node_bit = bit + 1;
+			pfn = bm->cur[index].zone->start_pfn + bm->cur[index].node_pfn + bit;
+			bm->cur[index].node_bit = bit + 1;
 			return pfn;
 		}
-	} while (rtree_next_node(bm));
+	} while (rtree_next_node(bm, index));
 
 	return BM_END_OF_MAP;
 }
 
-/**
- *	This structure represents a range of page frames the contents of which
- *	should not be saved during the suspend.
- */
-
-struct nosave_region {
-	struct list_head list;
-	unsigned long start_pfn;
-	unsigned long end_pfn;
-};
-
-static LIST_HEAD(nosave_regions);
+LIST_HEAD(nosave_regions);
 
 /**
  *	register_nosave_region - register a range of page frames the contents
@@ -889,37 +927,37 @@ static struct memory_bitmap *free_pages_map;
 void swsusp_set_page_free(struct page *page)
 {
 	if (free_pages_map)
-		memory_bm_set_bit(free_pages_map, page_to_pfn(page));
+		memory_bm_set_bit(free_pages_map, 0, page_to_pfn(page));
 }
 
 static int swsusp_page_is_free(struct page *page)
 {
 	return free_pages_map ?
-		memory_bm_test_bit(free_pages_map, page_to_pfn(page)) : 0;
+		memory_bm_test_bit(free_pages_map, 0, page_to_pfn(page)) : 0;
 }
 
 void swsusp_unset_page_free(struct page *page)
 {
 	if (free_pages_map)
-		memory_bm_clear_bit(free_pages_map, page_to_pfn(page));
+		memory_bm_clear_bit(free_pages_map, 0, page_to_pfn(page));
 }
 
 static void swsusp_set_page_forbidden(struct page *page)
 {
 	if (forbidden_pages_map)
-		memory_bm_set_bit(forbidden_pages_map, page_to_pfn(page));
+		memory_bm_set_bit(forbidden_pages_map, 0, page_to_pfn(page));
 }
 
 int swsusp_page_is_forbidden(struct page *page)
 {
 	return forbidden_pages_map ?
-		memory_bm_test_bit(forbidden_pages_map, page_to_pfn(page)) : 0;
+		memory_bm_test_bit(forbidden_pages_map, 0, page_to_pfn(page)) : 0;
 }
 
 static void swsusp_unset_page_forbidden(struct page *page)
 {
 	if (forbidden_pages_map)
-		memory_bm_clear_bit(forbidden_pages_map, page_to_pfn(page));
+		memory_bm_clear_bit(forbidden_pages_map, 0, page_to_pfn(page));
 }
 
 /**
@@ -950,7 +988,7 @@ static void mark_nosave_pages(struct memory_bitmap *bm)
 				 * touch the PFNs for which the error is
 				 * returned anyway.
 				 */
-				mem_bm_set_bit_check(bm, pfn);
+				mem_bm_set_bit_check(bm, 0, pfn);
 			}
 	}
 }
@@ -1078,7 +1116,7 @@ static unsigned int count_free_highmem_pages(void)
  *	We should save the page if it isn't Nosave or NosaveFree, or Reserved,
  *	and it isn't a part of a free chunk of pages.
  */
-static struct page *saveable_highmem_page(struct zone *zone, unsigned long pfn)
+struct page *saveable_highmem_page(struct zone *zone, unsigned long pfn)
 {
 	struct page *page;
 
@@ -1125,11 +1163,6 @@ static unsigned int count_highmem_pages(void)
 	}
 	return n;
 }
-#else
-static inline void *saveable_highmem_page(struct zone *z, unsigned long p)
-{
-	return NULL;
-}
 #endif /* CONFIG_HIGHMEM */
 
 /**
@@ -1140,7 +1173,7 @@ static inline void *saveable_highmem_page(struct zone *z, unsigned long p)
  *	of pages statically defined as 'unsaveable', and it isn't a part of
  *	a free chunk of pages.
  */
-static struct page *saveable_page(struct zone *zone, unsigned long pfn)
+struct page *saveable_page(struct zone *zone, unsigned long pfn)
 {
 	struct page *page;
 
@@ -1278,15 +1311,15 @@ copy_data_pages(struct memory_bitmap *copy_bm, struct memory_bitmap *orig_bm)
 		max_zone_pfn = zone_end_pfn(zone);
 		for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
 			if (page_is_saveable(zone, pfn))
-				memory_bm_set_bit(orig_bm, pfn);
+				memory_bm_set_bit(orig_bm, 0, pfn);
 	}
 	memory_bm_position_reset(orig_bm);
 	memory_bm_position_reset(copy_bm);
 	for(;;) {
-		pfn = memory_bm_next_pfn(orig_bm);
+		pfn = memory_bm_next_pfn(orig_bm, 0);
 		if (unlikely(pfn == BM_END_OF_MAP))
 			break;
-		copy_data_page(memory_bm_next_pfn(copy_bm), pfn);
+		copy_data_page(memory_bm_next_pfn(copy_bm, 0), pfn);
 	}
 }
 
@@ -1332,8 +1365,8 @@ void swsusp_free(void)
 	memory_bm_position_reset(free_pages_map);
 
 loop:
-	fr_pfn = memory_bm_next_pfn(free_pages_map);
-	fb_pfn = memory_bm_next_pfn(forbidden_pages_map);
+	fr_pfn = memory_bm_next_pfn(free_pages_map, 0);
+	fb_pfn = memory_bm_next_pfn(forbidden_pages_map, 0);
 
 	/*
 	 * Find the next bit set in both bitmaps. This is guaranteed to
@@ -1341,16 +1374,16 @@ loop:
 	 */
 	do {
 		if (fb_pfn < fr_pfn)
-			fb_pfn = memory_bm_next_pfn(forbidden_pages_map);
+			fb_pfn = memory_bm_next_pfn(forbidden_pages_map, 0);
 		if (fr_pfn < fb_pfn)
-			fr_pfn = memory_bm_next_pfn(free_pages_map);
+			fr_pfn = memory_bm_next_pfn(free_pages_map, 0);
 	} while (fb_pfn != fr_pfn);
 
 	if (fr_pfn != BM_END_OF_MAP && pfn_valid(fr_pfn)) {
 		struct page *page = pfn_to_page(fr_pfn);
 
-		memory_bm_clear_current(forbidden_pages_map);
-		memory_bm_clear_current(free_pages_map);
+		memory_bm_clear_current(forbidden_pages_map, 0);
+		memory_bm_clear_current(free_pages_map, 0);
 		__free_page(page);
 		goto loop;
 	}
@@ -1385,7 +1418,7 @@ static unsigned long preallocate_image_pages(unsigned long nr_pages, gfp_t mask)
 		page = alloc_image_page(mask);
 		if (!page)
 			break;
-		memory_bm_set_bit(&copy_bm, page_to_pfn(page));
+		memory_bm_set_bit(&copy_bm, 0, page_to_pfn(page));
 		if (PageHighMem(page))
 			alloc_highmem++;
 		else
@@ -1481,7 +1514,7 @@ static unsigned long free_unnecessary_pages(void)
 	memory_bm_position_reset(&copy_bm);
 
 	while (to_free_normal > 0 || to_free_highmem > 0) {
-		unsigned long pfn = memory_bm_next_pfn(&copy_bm);
+		unsigned long pfn = memory_bm_next_pfn(&copy_bm, 0);
 		struct page *page = pfn_to_page(pfn);
 
 		if (PageHighMem(page)) {
@@ -1495,7 +1528,7 @@ static unsigned long free_unnecessary_pages(void)
 			to_free_normal--;
 			alloc_normal--;
 		}
-		memory_bm_clear_bit(&copy_bm, pfn);
+		memory_bm_clear_bit(&copy_bm, 0, pfn);
 		swsusp_unset_page_forbidden(page);
 		swsusp_unset_page_free(page);
 		__free_page(page);
@@ -1780,7 +1813,7 @@ alloc_highmem_pages(struct memory_bitmap *bm, unsigned int nr_highmem)
 		struct page *page;
 
 		page = alloc_image_page(__GFP_HIGHMEM|__GFP_KSWAPD_RECLAIM);
-		memory_bm_set_bit(bm, page_to_pfn(page));
+		memory_bm_set_bit(bm, 0, page_to_pfn(page));
 	}
 	return nr_highmem;
 }
@@ -1823,7 +1856,7 @@ swsusp_alloc(struct memory_bitmap *orig_bm, struct memory_bitmap *copy_bm,
 			page = alloc_image_page(GFP_ATOMIC | __GFP_COLD);
 			if (!page)
 				goto err_out;
-			memory_bm_set_bit(copy_bm, page_to_pfn(page));
+			memory_bm_set_bit(copy_bm, 0, page_to_pfn(page));
 		}
 	}
 
@@ -1838,6 +1871,9 @@ asmlinkage __visible int swsusp_save(void)
 {
 	unsigned int nr_pages, nr_highmem;
 
+        if (toi_running)
+            return toi_post_context_save();
+
 	printk(KERN_INFO "PM: Creating hibernation image:\n");
 
 	drain_local_pages(NULL);
@@ -1885,7 +1921,7 @@ static int init_header_complete(struct swsusp_info *info)
 	return 0;
 }
 
-static char *check_image_kernel(struct swsusp_info *info)
+char *check_image_kernel(struct swsusp_info *info)
 {
 	if (info->version_code != LINUX_VERSION_CODE)
 		return "kernel version";
@@ -1906,7 +1942,7 @@ unsigned long snapshot_get_image_size(void)
 	return nr_copy_pages + nr_meta_pages + 1;
 }
 
-static int init_header(struct swsusp_info *info)
+int init_header(struct swsusp_info *info)
 {
 	memset(info, 0, sizeof(struct swsusp_info));
 	info->num_physpages = get_num_physpages();
@@ -1928,7 +1964,7 @@ pack_pfns(unsigned long *buf, struct memory_bitmap *bm)
 	int j;
 
 	for (j = 0; j < PAGE_SIZE / sizeof(long); j++) {
-		buf[j] = memory_bm_next_pfn(bm);
+		buf[j] = memory_bm_next_pfn(bm, 0);
 		if (unlikely(buf[j] == BM_END_OF_MAP))
 			break;
 		/* Save page key for data page (s390 only). */
@@ -1979,7 +2015,7 @@ int snapshot_read_next(struct snapshot_handle *handle)
 	} else {
 		struct page *page;
 
-		page = pfn_to_page(memory_bm_next_pfn(&copy_bm));
+		page = pfn_to_page(memory_bm_next_pfn(&copy_bm, 0));
 		if (PageHighMem(page)) {
 			/* Highmem pages are copied to the buffer,
 			 * because we can't return with a kmapped
@@ -2021,7 +2057,7 @@ static int mark_unsafe_pages(struct memory_bitmap *bm)
 	/* Mark pages that correspond to the "original" pfns as "unsafe" */
 	memory_bm_position_reset(bm);
 	do {
-		pfn = memory_bm_next_pfn(bm);
+		pfn = memory_bm_next_pfn(bm, 0);
 		if (likely(pfn != BM_END_OF_MAP)) {
 			if (likely(pfn_valid(pfn)))
 				swsusp_set_page_free(pfn_to_page(pfn));
@@ -2041,10 +2077,10 @@ duplicate_memory_bitmap(struct memory_bitmap *dst, struct memory_bitmap *src)
 	unsigned long pfn;
 
 	memory_bm_position_reset(src);
-	pfn = memory_bm_next_pfn(src);
+	pfn = memory_bm_next_pfn(src, 0);
 	while (pfn != BM_END_OF_MAP) {
-		memory_bm_set_bit(dst, pfn);
-		pfn = memory_bm_next_pfn(src);
+		memory_bm_set_bit(dst, 0, pfn);
+		pfn = memory_bm_next_pfn(src, 0);
 	}
 }
 
@@ -2095,8 +2131,8 @@ static int unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm)
 		/* Extract and buffer page key for data page (s390 only). */
 		page_key_memorize(buf + j);
 
-		if (memory_bm_pfn_present(bm, buf[j]))
-			memory_bm_set_bit(bm, buf[j]);
+		if (memory_bm_pfn_present(bm, 0, buf[j]))
+			memory_bm_set_bit(bm, 0, buf[j]);
 		else
 			return -EFAULT;
 	}
@@ -2139,12 +2175,12 @@ static unsigned int count_highmem_image_pages(struct memory_bitmap *bm)
 	unsigned int cnt = 0;
 
 	memory_bm_position_reset(bm);
-	pfn = memory_bm_next_pfn(bm);
+	pfn = memory_bm_next_pfn(bm, 0);
 	while (pfn != BM_END_OF_MAP) {
 		if (PageHighMem(pfn_to_page(pfn)))
 			cnt++;
 
-		pfn = memory_bm_next_pfn(bm);
+		pfn = memory_bm_next_pfn(bm, 0);
 	}
 	return cnt;
 }
@@ -2189,7 +2225,7 @@ prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p)
 		page = alloc_page(__GFP_HIGHMEM);
 		if (!swsusp_page_is_free(page)) {
 			/* The page is "safe", set its bit the bitmap */
-			memory_bm_set_bit(bm, page_to_pfn(page));
+			memory_bm_set_bit(bm, 0, page_to_pfn(page));
 			safe_highmem_pages++;
 		}
 		/* Mark the page as allocated */
@@ -2247,7 +2283,7 @@ get_highmem_page_buffer(struct page *page, struct chain_allocator *ca)
 
 		/* Copy of the page will be stored in high memory */
 		kaddr = buffer;
-		tmp = pfn_to_page(memory_bm_next_pfn(safe_highmem_bm));
+		tmp = pfn_to_page(memory_bm_next_pfn(safe_highmem_bm, 0));
 		safe_highmem_pages--;
 		last_highmem_page = tmp;
 		pbe->copy_page = tmp;
@@ -2418,7 +2454,7 @@ static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca)
 {
 	struct pbe *pbe;
 	struct page *page;
-	unsigned long pfn = memory_bm_next_pfn(bm);
+	unsigned long pfn = memory_bm_next_pfn(bm, 0);
 
 	if (pfn == BM_END_OF_MAP)
 		return ERR_PTR(-EFAULT);
@@ -2605,3 +2641,82 @@ int restore_highmem(void)
 	return 0;
 }
 #endif /* CONFIG_HIGHMEM */
+
+struct memory_bitmap *pageset1_map, *pageset2_map, *free_map, *nosave_map,
+  *pageset1_copy_map, *io_map, *page_resave_map, *compare_map;
+
+int resume_attempted;
+
+int memory_bm_write(struct memory_bitmap *bm, int (*rw_chunk)
+	(int rw, struct toi_module_ops *owner, char *buffer, int buffer_size))
+{
+    int result;
+
+    memory_bm_position_reset(bm);
+
+    do {
+        result = rw_chunk(WRITE, NULL, (char *) bm->cur[0].node->data, PAGE_SIZE);
+
+        if (result)
+            return result;
+    } while (rtree_next_node(bm, 0));
+    return 0;
+}
+
+int memory_bm_read(struct memory_bitmap *bm, int (*rw_chunk)
+	(int rw, struct toi_module_ops *owner, char *buffer, int buffer_size))
+{
+    int result;
+
+    memory_bm_position_reset(bm);
+
+    do {
+        result = rw_chunk(READ, NULL, (char *) bm->cur[0].node->data, PAGE_SIZE);
+
+        if (result)
+            return result;
+
+    } while (rtree_next_node(bm, 0));
+    return 0;
+}
+
+int memory_bm_space_needed(struct memory_bitmap *bm)
+{
+    unsigned long bytes = 0;
+
+    memory_bm_position_reset(bm);
+    do {
+        bytes += PAGE_SIZE;
+    } while (rtree_next_node(bm, 0));
+    return bytes;
+}
+
+int toi_alloc_bitmap(struct memory_bitmap **bm)
+{
+    int error;
+    struct memory_bitmap *bm1;
+
+    bm1 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL);
+    if (!bm1)
+        return -ENOMEM;
+
+    error = memory_bm_create(bm1, GFP_KERNEL, PG_ANY);
+    if (error) {
+        printk("Error returned - %d.\n", error);
+        kfree(bm1);
+        return -ENOMEM;
+    }
+
+    *bm = bm1;
+    return 0;
+}
+
+void toi_free_bitmap(struct memory_bitmap **bm)
+{
+    if (!*bm)
+        return;
+
+    memory_bm_free(*bm, 0);
+    kfree(*bm);
+    *bm = NULL;
+}
diff --git a/kernel/power/tuxonice.h b/kernel/power/tuxonice.h
new file mode 100644
index 000000000..10b65633f
--- /dev/null
+++ b/kernel/power/tuxonice.h
@@ -0,0 +1,260 @@
+/*
+ * kernel/power/tuxonice.h
+ *
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * It contains declarations used throughout swsusp.
+ *
+ */
+
+#ifndef KERNEL_POWER_TOI_H
+#define KERNEL_POWER_TOI_H
+
+#include <linux/delay.h>
+#include <linux/bootmem.h>
+#include <linux/suspend.h>
+#include <linux/fs.h>
+#include <asm/setup.h>
+#include "tuxonice_pageflags.h"
+#include "power.h"
+
+#define TOI_CORE_VERSION "3.3"
+#define        TOI_HEADER_VERSION 3
+#define MY_BOOT_KERNEL_DATA_VERSION 4
+
+struct toi_boot_kernel_data {
+        int version;
+        int size;
+        unsigned long toi_action;
+        unsigned long toi_debug_state;
+        u32 toi_default_console_level;
+        int toi_io_time[2][2];
+        char toi_nosave_commandline[COMMAND_LINE_SIZE];
+        unsigned long pages_used[33];
+        unsigned long incremental_bytes_in;
+        unsigned long incremental_bytes_out;
+        unsigned long compress_bytes_in;
+        unsigned long compress_bytes_out;
+        unsigned long pruned_pages;
+};
+
+extern struct toi_boot_kernel_data toi_bkd;
+
+/* Location of book kernel data struct in kernel being resumed */
+extern unsigned long boot_kernel_data_buffer;
+
+/*                 == Action states ==                 */
+
+enum {
+        TOI_REBOOT,
+        TOI_PAUSE,
+        TOI_LOGALL,
+        TOI_CAN_CANCEL,
+        TOI_KEEP_IMAGE,
+        TOI_FREEZER_TEST,
+        TOI_SINGLESTEP,
+        TOI_PAUSE_NEAR_PAGESET_END,
+        TOI_TEST_FILTER_SPEED,
+        TOI_TEST_BIO,
+        TOI_NO_PAGESET2,
+        TOI_IGNORE_ROOTFS,
+        TOI_REPLACE_SWSUSP,
+        TOI_PAGESET2_FULL,
+        TOI_ABORT_ON_RESAVE_NEEDED,
+        TOI_NO_MULTITHREADED_IO,
+        TOI_NO_DIRECT_LOAD, /* Obsolete */
+        TOI_LATE_CPU_HOTPLUG, /* Obsolete */
+        TOI_GET_MAX_MEM_ALLOCD,
+        TOI_NO_FLUSHER_THREAD,
+        TOI_NO_PS2_IF_UNNEEDED,
+        TOI_POST_RESUME_BREAKPOINT,
+        TOI_NO_READAHEAD,
+        TOI_TRACE_DEBUG_ON,
+        TOI_INCREMENTAL_IMAGE,
+};
+
+extern unsigned long toi_bootflags_mask;
+
+#define clear_action_state(bit) (test_and_clear_bit(bit, &toi_bkd.toi_action))
+
+/*                 == Result states ==                 */
+
+enum {
+        TOI_ABORTED,
+        TOI_ABORT_REQUESTED,
+        TOI_NOSTORAGE_AVAILABLE,
+        TOI_INSUFFICIENT_STORAGE,
+        TOI_FREEZING_FAILED,
+        TOI_KEPT_IMAGE,
+        TOI_WOULD_EAT_MEMORY,
+        TOI_UNABLE_TO_FREE_ENOUGH_MEMORY,
+        TOI_PM_SEM,
+        TOI_DEVICE_REFUSED,
+        TOI_SYSDEV_REFUSED,
+        TOI_EXTRA_PAGES_ALLOW_TOO_SMALL,
+        TOI_UNABLE_TO_PREPARE_IMAGE,
+        TOI_FAILED_MODULE_INIT,
+        TOI_FAILED_MODULE_CLEANUP,
+        TOI_FAILED_IO,
+        TOI_OUT_OF_MEMORY,
+        TOI_IMAGE_ERROR,
+        TOI_PLATFORM_PREP_FAILED,
+        TOI_CPU_HOTPLUG_FAILED,
+        TOI_ARCH_PREPARE_FAILED, /* Removed Linux-3.0 */
+        TOI_RESAVE_NEEDED,
+        TOI_CANT_SUSPEND,
+        TOI_NOTIFIERS_PREPARE_FAILED,
+        TOI_PRE_SNAPSHOT_FAILED,
+        TOI_PRE_RESTORE_FAILED,
+        TOI_USERMODE_HELPERS_ERR,
+        TOI_CANT_USE_ALT_RESUME,
+        TOI_HEADER_TOO_BIG,
+        TOI_WAKEUP_EVENT,
+        TOI_SYSCORE_REFUSED,
+        TOI_DPM_PREPARE_FAILED,
+        TOI_DPM_SUSPEND_FAILED,
+        TOI_NUM_RESULT_STATES        /* Used in printing debug info only */
+};
+
+extern unsigned long toi_result;
+
+#define set_result_state(bit) (test_and_set_bit(bit, &toi_result))
+#define set_abort_result(bit) (test_and_set_bit(TOI_ABORTED, &toi_result), \
+                                test_and_set_bit(bit, &toi_result))
+#define clear_result_state(bit) (test_and_clear_bit(bit, &toi_result))
+#define test_result_state(bit) (test_bit(bit, &toi_result))
+
+/*         == Debug sections and levels ==         */
+
+/* debugging levels. */
+enum {
+        TOI_STATUS = 0,
+        TOI_ERROR = 2,
+        TOI_LOW,
+        TOI_MEDIUM,
+        TOI_HIGH,
+        TOI_VERBOSE,
+};
+
+enum {
+        TOI_ANY_SECTION,
+        TOI_EAT_MEMORY,
+        TOI_IO,
+        TOI_HEADER,
+        TOI_WRITER,
+        TOI_MEMORY,
+        TOI_PAGEDIR,
+        TOI_COMPRESS,
+        TOI_BIO,
+};
+
+#define set_debug_state(bit) (test_and_set_bit(bit, &toi_bkd.toi_debug_state))
+#define clear_debug_state(bit) \
+        (test_and_clear_bit(bit, &toi_bkd.toi_debug_state))
+#define test_debug_state(bit) (test_bit(bit, &toi_bkd.toi_debug_state))
+
+/*                == Steps in hibernating ==        */
+
+enum {
+        STEP_HIBERNATE_PREPARE_IMAGE,
+        STEP_HIBERNATE_SAVE_IMAGE,
+        STEP_HIBERNATE_POWERDOWN,
+        STEP_RESUME_CAN_RESUME,
+        STEP_RESUME_LOAD_PS1,
+        STEP_RESUME_DO_RESTORE,
+        STEP_RESUME_READ_PS2,
+        STEP_RESUME_GO,
+        STEP_RESUME_ALT_IMAGE,
+        STEP_CLEANUP,
+        STEP_QUIET_CLEANUP
+};
+
+/*                == TuxOnIce states ==
+        (see also include/linux/suspend.h)        */
+
+#define get_toi_state()  (toi_state)
+#define restore_toi_state(saved_state) \
+        do { toi_state = saved_state; } while (0)
+
+/*                == Module support ==                */
+
+struct toi_core_fns {
+        int (*post_context_save)(void);
+        unsigned long (*get_nonconflicting_page)(void);
+        int (*try_hibernate)(void);
+        void (*try_resume)(void);
+};
+
+extern struct toi_core_fns *toi_core_fns;
+
+/*                == All else ==                        */
+#define KB(x) ((x) << (PAGE_SHIFT - 10))
+#define MB(x) ((x) >> (20 - PAGE_SHIFT))
+
+extern int toi_start_anything(int toi_or_resume);
+extern void toi_finish_anything(int toi_or_resume);
+
+extern int save_image_part1(void);
+extern int toi_atomic_restore(void);
+
+extern int toi_try_hibernate(void);
+extern void toi_try_resume(void);
+
+extern int __toi_post_context_save(void);
+
+extern unsigned int nr_hibernates;
+extern char alt_resume_param[256];
+
+extern void copyback_post(void);
+extern int toi_hibernate(void);
+extern unsigned long extra_pd1_pages_used;
+
+#define SECTOR_SIZE 512
+
+extern void toi_early_boot_message(int can_erase_image, int default_answer,
+        char *warning_reason, ...);
+
+extern int do_check_can_resume(void);
+extern int do_toi_step(int step);
+extern int toi_launch_userspace_program(char *command, int channel_no,
+                int wait, int debug);
+
+extern char tuxonice_signature[9];
+
+extern int toi_start_other_threads(void);
+extern void toi_stop_other_threads(void);
+
+extern int toi_trace_index;
+#define TOI_TRACE_DEBUG(PFN, DESC, ...) \
+    do { \
+        if (test_action_state(TOI_TRACE_DEBUG_ON)) { \
+            printk("*TOI* %ld %02d" DESC "\n", PFN, toi_trace_index, ##__VA_ARGS__); \
+        } \
+    } while(0)
+
+#ifdef CONFIG_TOI_KEEP_IMAGE
+#define toi_keeping_image (test_action_state(TOI_KEEP_IMAGE) || test_action_state(TOI_INCREMENTAL_IMAGE))
+#else
+#define toi_keeping_image (0)
+#endif
+
+#ifdef CONFIG_TOI_INCREMENTAL
+extern void toi_reset_dirtiness_one(unsigned long pfn, int verbose);
+extern int toi_reset_dirtiness(int verbose);
+extern void toi_cbw_write(void);
+extern void toi_cbw_restore(void);
+extern int toi_allocate_cbw_data(void);
+extern void toi_free_cbw_data(void);
+extern int toi_cbw_init(void);
+extern void toi_mark_tasks_cbw(void);
+#else
+static inline int toi_reset_dirtiness(int verbose) { return 0; }
+#define toi_cbw_write() do { } while(0)
+#define toi_cbw_restore() do { } while(0)
+#define toi_allocate_cbw_data() do { } while(0)
+#define toi_free_cbw_data() do { } while(0)
+static inline int toi_cbw_init(void) { return 0; }
+#endif
+#endif
diff --git a/kernel/power/tuxonice_alloc.c b/kernel/power/tuxonice_alloc.c
new file mode 100644
index 000000000..1d8b1cbda
--- /dev/null
+++ b/kernel/power/tuxonice_alloc.c
@@ -0,0 +1,308 @@
+/*
+ * kernel/power/tuxonice_alloc.c
+ *
+ * Copyright (C) 2008-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ */
+
+#include <linux/export.h>
+#include <linux/slab.h>
+#include "tuxonice_modules.h"
+#include "tuxonice_alloc.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice.h"
+
+#define TOI_ALLOC_PATHS 41
+
+static DEFINE_MUTEX(toi_alloc_mutex);
+
+static struct toi_module_ops toi_alloc_ops;
+
+static int toi_fail_num;
+
+static atomic_t toi_alloc_count[TOI_ALLOC_PATHS],
+                toi_free_count[TOI_ALLOC_PATHS],
+                toi_test_count[TOI_ALLOC_PATHS],
+                toi_fail_count[TOI_ALLOC_PATHS];
+static int toi_cur_allocd[TOI_ALLOC_PATHS], toi_max_allocd[TOI_ALLOC_PATHS];
+static int cur_allocd, max_allocd;
+
+static char *toi_alloc_desc[TOI_ALLOC_PATHS] = {
+        "", /* 0 */
+        "get_io_info_struct",
+        "extent",
+        "extent (loading chain)",
+        "userui channel",
+        "userui arg", /* 5 */
+        "attention list metadata",
+        "extra pagedir memory metadata",
+        "bdev metadata",
+        "extra pagedir memory",
+        "header_locations_read", /* 10 */
+        "bio queue",
+        "prepare_readahead",
+        "i/o buffer",
+        "writer buffer in bio_init",
+        "checksum buffer", /* 15 */
+        "compression buffer",
+        "filewriter signature op",
+        "set resume param alloc1",
+        "set resume param alloc2",
+        "debugging info buffer", /* 20 */
+        "check can resume buffer",
+        "write module config buffer",
+        "read module config buffer",
+        "write image header buffer",
+        "read pageset1 buffer", /* 25 */
+        "get_have_image_data buffer",
+        "checksum page",
+        "worker rw loop",
+        "get nonconflicting page",
+        "ps1 load addresses", /* 30 */
+        "remove swap image",
+        "swap image exists",
+        "swap parse sig location",
+        "sysfs kobj",
+        "swap mark resume attempted buffer", /* 35 */
+        "cluster member",
+        "boot kernel data buffer",
+        "setting swap signature",
+        "block i/o bdev struct",
+        "copy before write", /* 40 */
+};
+
+#define MIGHT_FAIL(FAIL_NUM, FAIL_VAL) \
+        do { \
+                BUG_ON(FAIL_NUM >= TOI_ALLOC_PATHS); \
+                \
+                if (FAIL_NUM == toi_fail_num) { \
+                        atomic_inc(&toi_test_count[FAIL_NUM]); \
+                        toi_fail_num = 0; \
+                        return FAIL_VAL; \
+                } \
+        } while (0)
+
+static void alloc_update_stats(int fail_num, void *result, int size)
+{
+        if (!result) {
+                atomic_inc(&toi_fail_count[fail_num]);
+                return;
+        }
+
+        atomic_inc(&toi_alloc_count[fail_num]);
+        if (unlikely(test_action_state(TOI_GET_MAX_MEM_ALLOCD))) {
+                mutex_lock(&toi_alloc_mutex);
+                toi_cur_allocd[fail_num]++;
+                cur_allocd += size;
+                if (unlikely(cur_allocd > max_allocd)) {
+                        int i;
+
+                        for (i = 0; i < TOI_ALLOC_PATHS; i++)
+                                toi_max_allocd[i] = toi_cur_allocd[i];
+                        max_allocd = cur_allocd;
+                }
+                mutex_unlock(&toi_alloc_mutex);
+        }
+}
+
+static void free_update_stats(int fail_num, int size)
+{
+        BUG_ON(fail_num >= TOI_ALLOC_PATHS);
+        atomic_inc(&toi_free_count[fail_num]);
+        if (unlikely(atomic_read(&toi_free_count[fail_num]) >
+                                atomic_read(&toi_alloc_count[fail_num])))
+                dump_stack();
+        if (unlikely(test_action_state(TOI_GET_MAX_MEM_ALLOCD))) {
+                mutex_lock(&toi_alloc_mutex);
+                cur_allocd -= size;
+                toi_cur_allocd[fail_num]--;
+                mutex_unlock(&toi_alloc_mutex);
+        }
+}
+
+void *toi_kzalloc(int fail_num, size_t size, gfp_t flags)
+{
+        void *result;
+
+        if (toi_alloc_ops.enabled)
+                MIGHT_FAIL(fail_num, NULL);
+        result = kzalloc(size, flags);
+        if (toi_alloc_ops.enabled)
+                alloc_update_stats(fail_num, result, size);
+        if (fail_num == toi_trace_allocs)
+                dump_stack();
+        return result;
+}
+
+unsigned long toi_get_free_pages(int fail_num, gfp_t mask,
+                unsigned int order)
+{
+        unsigned long result;
+
+        mask |= ___GFP_TOI_NOTRACK;
+        if (toi_alloc_ops.enabled)
+                MIGHT_FAIL(fail_num, 0);
+        result = __get_free_pages(mask, order);
+        if (toi_alloc_ops.enabled)
+                alloc_update_stats(fail_num, (void *) result,
+                                PAGE_SIZE << order);
+        if (fail_num == toi_trace_allocs)
+                dump_stack();
+        return result;
+}
+
+struct page *toi_alloc_page(int fail_num, gfp_t mask)
+{
+        struct page *result;
+
+        if (toi_alloc_ops.enabled)
+                MIGHT_FAIL(fail_num, NULL);
+        mask |= ___GFP_TOI_NOTRACK;
+        result = alloc_page(mask);
+        if (toi_alloc_ops.enabled)
+                alloc_update_stats(fail_num, (void *) result, PAGE_SIZE);
+        if (fail_num == toi_trace_allocs)
+                dump_stack();
+        return result;
+}
+
+unsigned long toi_get_zeroed_page(int fail_num, gfp_t mask)
+{
+        unsigned long result;
+
+        if (toi_alloc_ops.enabled)
+                MIGHT_FAIL(fail_num, 0);
+        mask |= ___GFP_TOI_NOTRACK;
+        result = get_zeroed_page(mask);
+        if (toi_alloc_ops.enabled)
+                alloc_update_stats(fail_num, (void *) result, PAGE_SIZE);
+        if (fail_num == toi_trace_allocs)
+                dump_stack();
+        return result;
+}
+
+void toi_kfree(int fail_num, const void *arg, int size)
+{
+        if (arg && toi_alloc_ops.enabled)
+                free_update_stats(fail_num, size);
+
+        if (fail_num == toi_trace_allocs)
+                dump_stack();
+        kfree(arg);
+}
+
+void toi_free_page(int fail_num, unsigned long virt)
+{
+        if (virt && toi_alloc_ops.enabled)
+                free_update_stats(fail_num, PAGE_SIZE);
+
+        if (fail_num == toi_trace_allocs)
+                dump_stack();
+        free_page(virt);
+}
+
+void toi__free_page(int fail_num, struct page *page)
+{
+        if (page && toi_alloc_ops.enabled)
+                free_update_stats(fail_num, PAGE_SIZE);
+
+        if (fail_num == toi_trace_allocs)
+                dump_stack();
+        __free_page(page);
+}
+
+void toi_free_pages(int fail_num, struct page *page, int order)
+{
+        if (page && toi_alloc_ops.enabled)
+                free_update_stats(fail_num, PAGE_SIZE << order);
+
+        if (fail_num == toi_trace_allocs)
+                dump_stack();
+        __free_pages(page, order);
+}
+
+void toi_alloc_print_debug_stats(void)
+{
+        int i, header_done = 0;
+
+        if (!toi_alloc_ops.enabled)
+                return;
+
+        for (i = 0; i < TOI_ALLOC_PATHS; i++)
+                if (atomic_read(&toi_alloc_count[i]) !=
+                    atomic_read(&toi_free_count[i])) {
+                        if (!header_done) {
+                                printk(KERN_INFO "Idx  Allocs   Frees   Tests "
+                                        "  Fails     Max Description\n");
+                                header_done = 1;
+                        }
+
+                        printk(KERN_INFO "%3d %7d %7d %7d %7d %7d %s\n", i,
+                                atomic_read(&toi_alloc_count[i]),
+                                atomic_read(&toi_free_count[i]),
+                                atomic_read(&toi_test_count[i]),
+                                atomic_read(&toi_fail_count[i]),
+                                toi_max_allocd[i],
+                                toi_alloc_desc[i]);
+                }
+}
+
+static int toi_alloc_initialise(int starting_cycle)
+{
+        int i;
+
+        if (!starting_cycle)
+                return 0;
+
+        if (toi_trace_allocs)
+                dump_stack();
+
+        for (i = 0; i < TOI_ALLOC_PATHS; i++) {
+                atomic_set(&toi_alloc_count[i], 0);
+                atomic_set(&toi_free_count[i], 0);
+                atomic_set(&toi_test_count[i], 0);
+                atomic_set(&toi_fail_count[i], 0);
+                toi_cur_allocd[i] = 0;
+                toi_max_allocd[i] = 0;
+        };
+
+        max_allocd = 0;
+        cur_allocd = 0;
+        return 0;
+}
+
+static struct toi_sysfs_data sysfs_params[] = {
+        SYSFS_INT("failure_test", SYSFS_RW, &toi_fail_num, 0, 99, 0, NULL),
+        SYSFS_INT("trace", SYSFS_RW, &toi_trace_allocs, 0, TOI_ALLOC_PATHS, 0,
+                        NULL),
+        SYSFS_BIT("find_max_mem_allocated", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_GET_MAX_MEM_ALLOCD, 0),
+        SYSFS_INT("enabled", SYSFS_RW, &toi_alloc_ops.enabled, 0, 1, 0,
+                        NULL)
+};
+
+static struct toi_module_ops toi_alloc_ops = {
+        .type                                        = MISC_HIDDEN_MODULE,
+        .name                                        = "allocation debugging",
+        .directory                                = "alloc",
+        .module                                        = THIS_MODULE,
+        .early                                        = 1,
+        .initialise                                = toi_alloc_initialise,
+
+        .sysfs_data                = sysfs_params,
+        .num_sysfs_entries        = sizeof(sysfs_params) /
+                sizeof(struct toi_sysfs_data),
+};
+
+int toi_alloc_init(void)
+{
+        int result = toi_register_module(&toi_alloc_ops);
+        return result;
+}
+
+void toi_alloc_exit(void)
+{
+        toi_unregister_module(&toi_alloc_ops);
+}
diff --git a/kernel/power/tuxonice_alloc.h b/kernel/power/tuxonice_alloc.h
new file mode 100644
index 000000000..0cd6b686f
--- /dev/null
+++ b/kernel/power/tuxonice_alloc.h
@@ -0,0 +1,54 @@
+/*
+ * kernel/power/tuxonice_alloc.h
+ *
+ * Copyright (C) 2008-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ */
+
+#include <linux/slab.h>
+#define TOI_WAIT_GFP (GFP_NOFS | __GFP_NOWARN)
+#define TOI_ATOMIC_GFP (GFP_ATOMIC | __GFP_NOWARN)
+
+#ifdef CONFIG_PM_DEBUG
+extern void *toi_kzalloc(int fail_num, size_t size, gfp_t flags);
+extern void toi_kfree(int fail_num, const void *arg, int size);
+
+extern unsigned long toi_get_free_pages(int fail_num, gfp_t mask,
+                unsigned int order);
+#define toi_get_free_page(FAIL_NUM, MASK) toi_get_free_pages(FAIL_NUM, MASK, 0)
+extern unsigned long toi_get_zeroed_page(int fail_num, gfp_t mask);
+extern void toi_free_page(int fail_num, unsigned long buf);
+extern void toi__free_page(int fail_num, struct page *page);
+extern void toi_free_pages(int fail_num, struct page *page, int order);
+extern struct page *toi_alloc_page(int fail_num, gfp_t mask);
+extern int toi_alloc_init(void);
+extern void toi_alloc_exit(void);
+
+extern void toi_alloc_print_debug_stats(void);
+
+#else /* CONFIG_PM_DEBUG */
+
+#define toi_kzalloc(FAIL, SIZE, FLAGS) (kzalloc(SIZE, FLAGS))
+#define toi_kfree(FAIL, ALLOCN, SIZE) (kfree(ALLOCN))
+
+#define toi_get_free_pages(FAIL, FLAGS, ORDER) __get_free_pages(FLAGS, ORDER)
+#define toi_get_free_page(FAIL, FLAGS) __get_free_page(FLAGS)
+#define toi_get_zeroed_page(FAIL, FLAGS) get_zeroed_page(FLAGS)
+#define toi_free_page(FAIL, ALLOCN) do { free_page(ALLOCN); } while (0)
+#define toi__free_page(FAIL, PAGE) __free_page(PAGE)
+#define toi_free_pages(FAIL, PAGE, ORDER) __free_pages(PAGE, ORDER)
+#define toi_alloc_page(FAIL, MASK) alloc_page(MASK)
+static inline int toi_alloc_init(void)
+{
+        return 0;
+}
+
+static inline void toi_alloc_exit(void) { }
+
+static inline void toi_alloc_print_debug_stats(void) { }
+
+#endif
+
+extern int toi_trace_allocs;
diff --git a/kernel/power/tuxonice_atomic_copy.c b/kernel/power/tuxonice_atomic_copy.c
new file mode 100644
index 000000000..5845217f8
--- /dev/null
+++ b/kernel/power/tuxonice_atomic_copy.c
@@ -0,0 +1,469 @@
+/*
+ * kernel/power/tuxonice_atomic_copy.c
+ *
+ * Copyright 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * Distributed under GPLv2.
+ *
+ * Routines for doing the atomic save/restore.
+ */
+
+#include <linux/suspend.h>
+#include <linux/highmem.h>
+#include <linux/cpu.h>
+#include <linux/freezer.h>
+#include <linux/console.h>
+#include <linux/syscore_ops.h>
+#include <linux/ftrace.h>
+#include <asm/suspend.h>
+#include "tuxonice.h"
+#include "tuxonice_storage.h"
+#include "tuxonice_power_off.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_io.h"
+#include "tuxonice_prepare_image.h"
+#include "tuxonice_pageflags.h"
+#include "tuxonice_checksum.h"
+#include "tuxonice_builtin.h"
+#include "tuxonice_atomic_copy.h"
+#include "tuxonice_alloc.h"
+#include "tuxonice_modules.h"
+
+unsigned long extra_pd1_pages_used;
+
+/**
+ * free_pbe_list - free page backup entries used by the atomic copy code.
+ * @list:        List to free.
+ * @highmem:        Whether the list is in highmem.
+ *
+ * Normally, this function isn't used. If, however, we need to abort before
+ * doing the atomic copy, we use this to free the pbes previously allocated.
+ **/
+static void free_pbe_list(struct pbe **list, int highmem)
+{
+        while (*list) {
+                int i;
+                struct pbe *free_pbe, *next_page = NULL;
+                struct page *page;
+
+                if (highmem) {
+                        page = (struct page *) *list;
+                        free_pbe = (struct pbe *) kmap(page);
+                } else {
+                        page = virt_to_page(*list);
+                        free_pbe = *list;
+                }
+
+                for (i = 0; i < PBES_PER_PAGE; i++) {
+                        if (!free_pbe)
+                                break;
+                        if (highmem)
+                                toi__free_page(29, free_pbe->address);
+                        else
+                                toi_free_page(29,
+                                        (unsigned long) free_pbe->address);
+                        free_pbe = free_pbe->next;
+                }
+
+                if (highmem) {
+                        if (free_pbe)
+                                next_page = free_pbe;
+                        kunmap(page);
+                } else {
+                        if (free_pbe)
+                                next_page = free_pbe;
+                }
+
+                toi__free_page(29, page);
+                *list = (struct pbe *) next_page;
+        };
+}
+
+/**
+ * copyback_post - post atomic-restore actions
+ *
+ * After doing the atomic restore, we have a few more things to do:
+ *        1) We want to retain some values across the restore, so we now copy
+ *        these from the nosave variables to the normal ones.
+ *        2) Set the status flags.
+ *        3) Resume devices.
+ *        4) Tell userui so it can redraw & restore settings.
+ *        5) Reread the page cache.
+ **/
+void copyback_post(void)
+{
+        struct toi_boot_kernel_data *bkd =
+                (struct toi_boot_kernel_data *) boot_kernel_data_buffer;
+
+        if (toi_activate_storage(1))
+                panic("Failed to reactivate our storage.");
+
+        toi_post_atomic_restore_modules(bkd);
+
+        toi_cond_pause(1, "About to reload secondary pagedir.");
+
+        if (read_pageset2(0))
+                panic("Unable to successfully reread the page cache.");
+
+        /*
+         * If the user wants to sleep again after resuming from full-off,
+         * it's most likely to be in order to suspend to ram, so we'll
+         * do this check after loading pageset2, to give them the fastest
+         * wakeup when they are ready to use the computer again.
+         */
+        toi_check_resleep();
+
+        if (test_action_state(TOI_INCREMENTAL_IMAGE))
+            toi_reset_dirtiness(1);
+}
+
+/**
+ * toi_copy_pageset1 - do the atomic copy of pageset1
+ *
+ * Make the atomic copy of pageset1. We can't use copy_page (as we once did)
+ * because we can't be sure what side effects it has. On my old Duron, with
+ * 3DNOW, kernel_fpu_begin increments preempt count, making our preempt
+ * count at resume time 4 instead of 3.
+ *
+ * We don't want to call kmap_atomic unconditionally because it has the side
+ * effect of incrementing the preempt count, which will leave it one too high
+ * post resume (the page containing the preempt count will be copied after
+ * its incremented. This is essentially the same problem.
+ **/
+void toi_copy_pageset1(void)
+{
+        int i;
+        unsigned long source_index, dest_index;
+
+        memory_bm_position_reset(pageset1_map);
+        memory_bm_position_reset(pageset1_copy_map);
+
+        source_index = memory_bm_next_pfn(pageset1_map, 0);
+        dest_index = memory_bm_next_pfn(pageset1_copy_map, 0);
+
+        for (i = 0; i < pagedir1.size; i++) {
+                unsigned long *origvirt, *copyvirt;
+                struct page *origpage, *copypage;
+                int loop = (PAGE_SIZE / sizeof(unsigned long)) - 1,
+                    was_present1, was_present2;
+
+                origpage = pfn_to_page(source_index);
+                copypage = pfn_to_page(dest_index);
+
+                origvirt = PageHighMem(origpage) ?
+                        kmap_atomic(origpage) :
+                        page_address(origpage);
+
+                copyvirt = PageHighMem(copypage) ?
+                        kmap_atomic(copypage) :
+                        page_address(copypage);
+
+                was_present1 = kernel_page_present(origpage);
+                if (!was_present1)
+                        kernel_map_pages(origpage, 1, 1);
+
+                was_present2 = kernel_page_present(copypage);
+                if (!was_present2)
+                        kernel_map_pages(copypage, 1, 1);
+
+                while (loop >= 0) {
+                        *(copyvirt + loop) = *(origvirt + loop);
+                        loop--;
+                }
+
+                if (!was_present1)
+                        kernel_map_pages(origpage, 1, 0);
+
+                if (!was_present2)
+                        kernel_map_pages(copypage, 1, 0);
+
+                if (PageHighMem(origpage))
+                        kunmap_atomic(origvirt);
+
+                if (PageHighMem(copypage))
+                        kunmap_atomic(copyvirt);
+
+                source_index = memory_bm_next_pfn(pageset1_map, 0);
+                dest_index = memory_bm_next_pfn(pageset1_copy_map, 0);
+        }
+}
+
+/**
+ * __toi_post_context_save - steps after saving the cpu context
+ *
+ * Steps taken after saving the CPU state to make the actual
+ * atomic copy.
+ *
+ * Called from swsusp_save in snapshot.c via toi_post_context_save.
+ **/
+int __toi_post_context_save(void)
+{
+        unsigned long old_ps1_size = pagedir1.size;
+
+        check_checksums();
+
+        free_checksum_pages();
+
+        toi_recalculate_image_contents(1);
+
+        extra_pd1_pages_used = pagedir1.size > old_ps1_size ?
+                pagedir1.size - old_ps1_size : 0;
+
+        if (extra_pd1_pages_used > extra_pd1_pages_allowance) {
+                printk(KERN_INFO "Pageset1 has grown by %lu pages. "
+                        "extra_pages_allowance is currently only %lu.\n",
+                        pagedir1.size - old_ps1_size,
+                        extra_pd1_pages_allowance);
+
+                /*
+                 * Highlevel code will see this, clear the state and
+                 * retry if we haven't already done so twice.
+                 */
+                if (any_to_free(1)) {
+                        set_abort_result(TOI_EXTRA_PAGES_ALLOW_TOO_SMALL);
+                        return 1;
+                }
+                if (try_allocate_extra_memory()) {
+                        printk(KERN_INFO "Failed to allocate the extra memory"
+                                        " needed. Restarting the process.");
+                        set_abort_result(TOI_EXTRA_PAGES_ALLOW_TOO_SMALL);
+                        return 1;
+                }
+                printk(KERN_INFO "However it looks like there's enough"
+                        " free ram and storage to handle this, so "
+                        " continuing anyway.");
+                /* 
+                 * What if try_allocate_extra_memory above calls
+                 * toi_allocate_extra_pagedir_memory and it allocs a new
+                 * slab page via toi_kzalloc which should be in ps1? So...
+                 */
+                toi_recalculate_image_contents(1);
+        }
+
+        if (!test_action_state(TOI_TEST_FILTER_SPEED) &&
+            !test_action_state(TOI_TEST_BIO))
+                toi_copy_pageset1();
+
+        return 0;
+}
+
+/**
+ * toi_hibernate - high level code for doing the atomic copy
+ *
+ * High-level code which prepares to do the atomic copy. Loosely based
+ * on the swsusp version, but with the following twists:
+ *        - We set toi_running so the swsusp code uses our code paths.
+ *        - We give better feedback regarding what goes wrong if there is a
+ *          problem.
+ *        - We use an extra function to call the assembly, just in case this code
+ *          is in a module (return address).
+ **/
+int toi_hibernate(void)
+{
+        int error;
+
+        error = toi_lowlevel_builtin();
+
+        if (!error) {
+                struct toi_boot_kernel_data *bkd =
+                        (struct toi_boot_kernel_data *) boot_kernel_data_buffer;
+
+                /*
+                 * The boot kernel's data may be larger (newer version) or
+                 * smaller (older version) than ours. Copy the minimum
+                 * of the two sizes, so that we don't overwrite valid values
+                 * from pre-atomic copy.
+                 */
+
+                memcpy(&toi_bkd, (char *) boot_kernel_data_buffer,
+                        min_t(int, sizeof(struct toi_boot_kernel_data),
+                                bkd->size));
+        }
+
+        return error;
+}
+
+/**
+ * toi_atomic_restore - prepare to do the atomic restore
+ *
+ * Get ready to do the atomic restore. This part gets us into the same
+ * state we are in prior to do calling do_toi_lowlevel while
+ * hibernating: hot-unplugging secondary cpus and freeze processes,
+ * before starting the thread that will do the restore.
+ **/
+int toi_atomic_restore(void)
+{
+        int error;
+
+        toi_prepare_status(DONT_CLEAR_BAR,        "Atomic restore.");
+
+        memcpy(&toi_bkd.toi_nosave_commandline, saved_command_line,
+                strlen(saved_command_line));
+
+        toi_pre_atomic_restore_modules(&toi_bkd);
+
+        if (add_boot_kernel_data_pbe())
+                goto Failed;
+
+        toi_prepare_status(DONT_CLEAR_BAR, "Doing atomic copy/restore.");
+
+        if (toi_go_atomic(PMSG_QUIESCE, 0))
+                goto Failed;
+
+        /* We'll ignore saved state, but this gets preempt count (etc) right */
+        save_processor_state();
+
+        error = swsusp_arch_resume();
+        /*
+         * Code below is only ever reached in case of failure. Otherwise
+         * execution continues at place where swsusp_arch_suspend was called.
+         *
+         * We don't know whether it's safe to continue (this shouldn't happen),
+         * so lets err on the side of caution.
+         */
+        BUG();
+
+Failed:
+        free_pbe_list(&restore_pblist, 0);
+#ifdef CONFIG_HIGHMEM
+        free_pbe_list(&restore_highmem_pblist, 1);
+#endif
+        return 1;
+}
+
+/**
+ * toi_go_atomic - do the actual atomic copy/restore
+ * @state:           The state to use for dpm_suspend_start & power_down calls.
+ * @suspend_time:  Whether we're suspending or resuming.
+ **/
+int toi_go_atomic(pm_message_t state, int suspend_time)
+{
+  if (suspend_time) {
+    if (platform_begin(1)) {
+      set_abort_result(TOI_PLATFORM_PREP_FAILED);
+      toi_end_atomic(ATOMIC_STEP_PLATFORM_END, suspend_time, 3);
+      return 1;
+    }
+
+    if (dpm_prepare(PMSG_FREEZE)) {
+      set_abort_result(TOI_DPM_PREPARE_FAILED);
+      dpm_complete(PMSG_RECOVER);
+      toi_end_atomic(ATOMIC_STEP_PLATFORM_END, suspend_time, 3);
+      return 1;
+    }
+  }
+
+        suspend_console();
+        pm_restrict_gfp_mask();
+
+  if (suspend_time) {
+    if (dpm_suspend(state)) {
+      set_abort_result(TOI_DPM_SUSPEND_FAILED);
+      toi_end_atomic(ATOMIC_STEP_DEVICE_RESUME, suspend_time, 3);
+      return 1;
+    }
+  } else {
+    if (dpm_suspend_start(state)) {
+      set_abort_result(TOI_DPM_SUSPEND_FAILED);
+      toi_end_atomic(ATOMIC_STEP_DEVICE_RESUME, suspend_time, 3);
+      return 1;
+    }
+  }
+
+        /* At this point, dpm_suspend_start() has been called, but *not*
+         * dpm_suspend_noirq(). We *must* dpm_suspend_noirq() now.
+         * Otherwise, drivers for some devices (e.g. interrupt controllers)
+         * become desynchronized with the actual state of the hardware
+         * at resume time, and evil weirdness ensues.
+         */
+
+        if (dpm_suspend_end(state)) {
+                set_abort_result(TOI_DEVICE_REFUSED);
+                toi_end_atomic(ATOMIC_STEP_DEVICE_RESUME, suspend_time, 1);
+                return 1;
+        }
+
+        if (suspend_time) {
+                if (platform_pre_snapshot(1))
+                        set_abort_result(TOI_PRE_SNAPSHOT_FAILED);
+        } else {
+                if (platform_pre_restore(1))
+                        set_abort_result(TOI_PRE_RESTORE_FAILED);
+        }
+
+        if (test_result_state(TOI_ABORTED)) {
+                toi_end_atomic(ATOMIC_STEP_PLATFORM_FINISH, suspend_time, 1);
+                return 1;
+        }
+
+        if (disable_nonboot_cpus()) {
+            set_abort_result(TOI_CPU_HOTPLUG_FAILED);
+            toi_end_atomic(ATOMIC_STEP_CPU_HOTPLUG,
+                    suspend_time, 1);
+            return 1;
+        }
+
+        local_irq_disable();
+
+        if (syscore_suspend()) {
+                set_abort_result(TOI_SYSCORE_REFUSED);
+                toi_end_atomic(ATOMIC_STEP_IRQS, suspend_time, 1);
+                return 1;
+        }
+
+        if (suspend_time && pm_wakeup_pending()) {
+                set_abort_result(TOI_WAKEUP_EVENT);
+                toi_end_atomic(ATOMIC_STEP_SYSCORE_RESUME, suspend_time, 1);
+                return 1;
+        }
+        return 0;
+}
+
+/**
+ * toi_end_atomic - post atomic copy/restore routines
+ * @stage:                What step to start at.
+ * @suspend_time:        Whether we're suspending or resuming.
+ * @error:                Whether we're recovering from an error.
+ **/
+void toi_end_atomic(int stage, int suspend_time, int error)
+{
+        pm_message_t msg = suspend_time ? (error ? PMSG_RECOVER : PMSG_THAW) :
+                PMSG_RESTORE;
+
+        switch (stage) {
+        case ATOMIC_ALL_STEPS:
+                if (!suspend_time) {
+                        events_check_enabled = false;
+                }
+                platform_leave(1);
+        case ATOMIC_STEP_SYSCORE_RESUME:
+                syscore_resume();
+        case ATOMIC_STEP_IRQS:
+                local_irq_enable();
+        case ATOMIC_STEP_CPU_HOTPLUG:
+                enable_nonboot_cpus();
+        case ATOMIC_STEP_PLATFORM_FINISH:
+                if (!suspend_time && error & 2)
+                        platform_restore_cleanup(1);
+                else 
+                        platform_finish(1);
+                dpm_resume_start(msg);
+        case ATOMIC_STEP_DEVICE_RESUME:
+                if (suspend_time && (error & 2))
+                        platform_recover(1);
+                dpm_resume(msg);
+                if (!toi_in_suspend()) {
+                    dpm_resume_end(PMSG_RECOVER);
+                }
+                if (error || !toi_in_suspend()) {
+                        pm_restore_gfp_mask();
+                }
+                resume_console();
+        case ATOMIC_STEP_DPM_COMPLETE:
+                dpm_complete(msg);
+        case ATOMIC_STEP_PLATFORM_END:
+                platform_end(1);
+
+                toi_prepare_status(DONT_CLEAR_BAR, "Post atomic.");
+        }
+}
diff --git a/kernel/power/tuxonice_atomic_copy.h b/kernel/power/tuxonice_atomic_copy.h
new file mode 100644
index 000000000..e2d2b4fb3
--- /dev/null
+++ b/kernel/power/tuxonice_atomic_copy.h
@@ -0,0 +1,25 @@
+/*
+ * kernel/power/tuxonice_atomic_copy.h
+ *
+ * Copyright 2008-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * Distributed under GPLv2.
+ *
+ * Routines for doing the atomic save/restore.
+ */
+
+enum {
+        ATOMIC_ALL_STEPS,
+        ATOMIC_STEP_SYSCORE_RESUME,
+        ATOMIC_STEP_IRQS,
+        ATOMIC_STEP_CPU_HOTPLUG,
+        ATOMIC_STEP_PLATFORM_FINISH,
+        ATOMIC_STEP_DEVICE_RESUME,
+        ATOMIC_STEP_DPM_COMPLETE,
+        ATOMIC_STEP_PLATFORM_END,
+};
+
+int toi_go_atomic(pm_message_t state, int toi_time);
+void toi_end_atomic(int stage, int toi_time, int error);
+
+extern void platform_recover(int platform_mode);
diff --git a/kernel/power/tuxonice_bio.h b/kernel/power/tuxonice_bio.h
new file mode 100644
index 000000000..9d52a3b69
--- /dev/null
+++ b/kernel/power/tuxonice_bio.h
@@ -0,0 +1,78 @@
+/*
+ * kernel/power/tuxonice_bio.h
+ *
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * Distributed under GPLv2.
+ *
+ * This file contains declarations for functions exported from
+ * tuxonice_bio.c, which contains low level io functions.
+ */
+
+#include <linux/buffer_head.h>
+#include "tuxonice_extent.h"
+
+void toi_put_extent_chain(struct hibernate_extent_chain *chain);
+int toi_add_to_extent_chain(struct hibernate_extent_chain *chain,
+                unsigned long start, unsigned long end);
+
+struct hibernate_extent_saved_state {
+        int extent_num;
+        struct hibernate_extent *extent_ptr;
+        unsigned long offset;
+};
+
+struct toi_bdev_info {
+        struct toi_bdev_info *next;
+        struct hibernate_extent_chain blocks;
+        struct block_device *bdev;
+        struct toi_module_ops *allocator;
+        int allocator_index;
+        struct hibernate_extent_chain allocations;
+        char name[266]; /* "swap on " or "file " + up to 256 chars */
+
+        /* Saved in header */
+        char uuid[17];
+        dev_t dev_t;
+        int prio;
+        int bmap_shift;
+        int blocks_per_page;
+        unsigned long pages_used;
+        struct hibernate_extent_saved_state saved_state[4];
+};
+
+struct toi_extent_iterate_state {
+        struct toi_bdev_info *current_chain;
+        int num_chains;
+        int saved_chain_number[4];
+        struct toi_bdev_info *saved_chain_ptr[4];
+};
+
+/*
+ * Our exported interface so the swapwriter and filewriter don't
+ * need these functions duplicated.
+ */
+struct toi_bio_ops {
+        int (*bdev_page_io) (int rw, struct block_device *bdev, long pos,
+                        struct page *page);
+        int (*register_storage)(struct toi_bdev_info *new);
+        void (*free_storage)(void);
+};
+
+struct toi_allocator_ops {
+        unsigned long (*toi_swap_storage_available) (void);
+};
+
+extern struct toi_bio_ops toi_bio_ops;
+
+extern char *toi_writer_buffer;
+extern int toi_writer_buffer_posn;
+
+struct toi_bio_allocator_ops {
+        int (*register_storage) (void);
+        unsigned long (*storage_available)(void);
+        int (*allocate_storage) (struct toi_bdev_info *, unsigned long);
+        int (*bmap) (struct toi_bdev_info *);
+        void (*free_storage) (struct toi_bdev_info *);
+        unsigned long (*free_unused_storage) (struct toi_bdev_info *, unsigned long used);
+};
diff --git a/kernel/power/tuxonice_bio_chains.c b/kernel/power/tuxonice_bio_chains.c
new file mode 100644
index 000000000..086a5527d
--- /dev/null
+++ b/kernel/power/tuxonice_bio_chains.c
@@ -0,0 +1,1126 @@
+/*
+ * kernel/power/tuxonice_bio_devinfo.c
+ *
+ * Copyright (C) 2009-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * Distributed under GPLv2.
+ *
+ */
+
+#include <linux/mm_types.h>
+#include "tuxonice_bio.h"
+#include "tuxonice_bio_internal.h"
+#include "tuxonice_alloc.h"
+#include "tuxonice_ui.h"
+#include "tuxonice.h"
+#include "tuxonice_io.h"
+
+static struct toi_bdev_info *prio_chain_head;
+static int num_chains;
+
+/* Pointer to current entry being loaded/saved. */
+struct toi_extent_iterate_state toi_writer_posn;
+
+#define metadata_size (sizeof(struct toi_bdev_info) - \
+                offsetof(struct toi_bdev_info, uuid))
+
+/*
+ * After section 0 (header) comes 2 => next_section[0] = 2
+ */
+static int next_section[3] = { 2, 3, 1 };
+
+/**
+ * dump_block_chains - print the contents of the bdev info array.
+ **/
+void dump_block_chains(void)
+{
+        int i = 0;
+        int j;
+        struct toi_bdev_info *cur_chain = prio_chain_head;
+
+        while (cur_chain) {
+                struct hibernate_extent *this = cur_chain->blocks.first;
+
+                printk(KERN_DEBUG "Chain %d (prio %d):", i, cur_chain->prio);
+
+                while (this) {
+                        printk(KERN_CONT " [%lu-%lu]%s", this->start,
+                                        this->end, this->next ? "," : "");
+                        this = this->next;
+                }
+
+                printk("\n");
+                cur_chain = cur_chain->next;
+                i++;
+        }
+
+        printk(KERN_DEBUG "Saved states:\n");
+        for (i = 0; i < 4; i++) {
+                printk(KERN_DEBUG "Slot %d: Chain %d.\n",
+                        i, toi_writer_posn.saved_chain_number[i]);
+
+                cur_chain = prio_chain_head;
+                j = 0;
+                while (cur_chain) {
+                        printk(KERN_DEBUG " Chain %d: Extent %d. Offset %lu.\n",
+                                        j, cur_chain->saved_state[i].extent_num,
+                                        cur_chain->saved_state[i].offset);
+                        cur_chain = cur_chain->next;
+                        j++;
+                }
+                printk(KERN_CONT "\n");
+        }
+}
+
+/**
+ *
+ **/
+static void toi_extent_chain_next(void)
+{
+        struct toi_bdev_info *this = toi_writer_posn.current_chain;
+
+        if (!this->blocks.current_extent)
+                return;
+
+        if (this->blocks.current_offset == this->blocks.current_extent->end) {
+                if (this->blocks.current_extent->next) {
+                        this->blocks.current_extent =
+                                this->blocks.current_extent->next;
+                        this->blocks.current_offset =
+                                this->blocks.current_extent->start;
+                } else {
+                        this->blocks.current_extent = NULL;
+                        this->blocks.current_offset = 0;
+                }
+        } else
+                this->blocks.current_offset++;
+}
+
+/**
+ *
+ */
+
+static struct toi_bdev_info *__find_next_chain_same_prio(void)
+{
+        struct toi_bdev_info *start_chain = toi_writer_posn.current_chain;
+        struct toi_bdev_info *this = start_chain;
+        int orig_prio = this->prio;
+
+        do {
+                this = this->next;
+
+                if (!this)
+                        this = prio_chain_head;
+
+                /* Back on original chain? Use it again. */
+                if (this == start_chain)
+                        return start_chain;
+
+        } while (!this->blocks.current_extent || this->prio != orig_prio);
+
+        return this;
+}
+
+static void find_next_chain(void)
+{
+        struct toi_bdev_info *this;
+
+        this = __find_next_chain_same_prio();
+
+        /*
+         * If we didn't get another chain of the same priority that we
+         * can use, look for the next priority.
+         */
+        while (this && !this->blocks.current_extent)
+                this = this->next;
+
+        toi_writer_posn.current_chain = this;
+}
+
+/**
+ * toi_extent_state_next - go to the next extent
+ * @blocks: The number of values to progress.
+ * @stripe_mode: Whether to spread usage across all chains.
+ *
+ * Given a state, progress to the next valid entry. We may begin in an
+ * invalid state, as we do when invoked after extent_state_goto_start below.
+ *
+ * When using compression and expected_compression > 0, we let the image size
+ * be larger than storage, so we can validly run out of data to return.
+ **/
+static unsigned long toi_extent_state_next(int blocks, int current_stream)
+{
+        int i;
+
+        if (!toi_writer_posn.current_chain)
+                return -ENOSPC;
+
+        /* Assume chains always have lengths that are multiples of @blocks */
+        for (i = 0; i < blocks; i++)
+                toi_extent_chain_next();
+
+        /* The header stream is not striped */
+        if (current_stream ||
+            !toi_writer_posn.current_chain->blocks.current_extent)
+                find_next_chain();
+
+        return  toi_writer_posn.current_chain ? 0 : -ENOSPC;
+}
+
+static void toi_insert_chain_in_prio_list(struct toi_bdev_info *this)
+{
+        struct toi_bdev_info **prev_ptr;
+        struct toi_bdev_info *cur;
+
+        /* Loop through the existing chain, finding where to insert it */
+        prev_ptr = &prio_chain_head;
+        cur = prio_chain_head;
+
+        while (cur && cur->prio >= this->prio) {
+                prev_ptr = &cur->next;
+                cur = cur->next;
+        }
+
+        this->next = *prev_ptr;
+        *prev_ptr = this;
+
+        this = prio_chain_head;
+        while (this)
+                this = this->next;
+        num_chains++;
+}
+
+/**
+ * toi_extent_state_goto_start - reinitialize an extent chain iterator
+ * @state:        Iterator to reinitialize
+ **/
+void toi_extent_state_goto_start(void)
+{
+        struct toi_bdev_info *this = prio_chain_head;
+
+        while (this) {
+                toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                        "Setting current extent to %p.", this->blocks.first);
+                this->blocks.current_extent = this->blocks.first;
+                if (this->blocks.current_extent) {
+                        toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                                        "Setting current offset to %lu.",
+                                        this->blocks.current_extent->start);
+                        this->blocks.current_offset =
+                                this->blocks.current_extent->start;
+                }
+
+                this = this->next;
+        }
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Setting current chain to %p.",
+                        prio_chain_head);
+        toi_writer_posn.current_chain = prio_chain_head;
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Leaving extent state goto start.");
+}
+
+/**
+ * toi_extent_state_save - save state of the iterator
+ * @state:                Current state of the chain
+ * @saved_state:        Iterator to populate
+ *
+ * Given a state and a struct hibernate_extent_state_store, save the current
+ * position in a format that can be used with relocated chains (at
+ * resume time).
+ **/
+void toi_extent_state_save(int slot)
+{
+        struct toi_bdev_info *cur_chain = prio_chain_head;
+        struct hibernate_extent *extent;
+        struct hibernate_extent_saved_state *chain_state;
+        int i = 0;
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "toi_extent_state_save, slot %d.",
+                        slot);
+
+        if (!toi_writer_posn.current_chain) {
+                toi_message(TOI_BIO, TOI_VERBOSE, 0, "No current chain => "
+                                "chain_num = -1.");
+                toi_writer_posn.saved_chain_number[slot] = -1;
+                return;
+        }
+
+        while (cur_chain) {
+                i++;
+                toi_message(TOI_BIO, TOI_VERBOSE, 0, "Saving chain %d (%p) "
+                                "state, slot %d.", i, cur_chain, slot);
+
+                chain_state = &cur_chain->saved_state[slot];
+
+                chain_state->offset = cur_chain->blocks.current_offset;
+
+                if (toi_writer_posn.current_chain == cur_chain) {
+                        toi_writer_posn.saved_chain_number[slot] = i;
+                        toi_message(TOI_BIO, TOI_VERBOSE, 0, "This is the chain "
+                                        "we were on => chain_num is %d.", i);
+                }
+
+                if (!cur_chain->blocks.current_extent) {
+                        chain_state->extent_num = 0;
+                        toi_message(TOI_BIO, TOI_VERBOSE, 0, "No current extent "
+                                        "for this chain => extent_num %d is 0.",
+                                        i);
+                        cur_chain = cur_chain->next;
+                        continue;
+                }
+
+                extent = cur_chain->blocks.first;
+                chain_state->extent_num = 1;
+
+                while (extent != cur_chain->blocks.current_extent) {
+                        chain_state->extent_num++;
+                        extent = extent->next;
+                }
+
+                toi_message(TOI_BIO, TOI_VERBOSE, 0, "extent num %d is %d.", i,
+                                chain_state->extent_num);
+
+                cur_chain = cur_chain->next;
+        }
+        toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                        "Completed saving extent state slot %d.", slot);
+}
+
+/**
+ * toi_extent_state_restore - restore the position saved by extent_state_save
+ * @state:                State to populate
+ * @saved_state:        Iterator saved to restore
+ **/
+void toi_extent_state_restore(int slot)
+{
+        int i = 0;
+        struct toi_bdev_info *cur_chain = prio_chain_head;
+        struct hibernate_extent_saved_state *chain_state;
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                        "toi_extent_state_restore - slot %d.", slot);
+
+        if (toi_writer_posn.saved_chain_number[slot] == -1) {
+                toi_writer_posn.current_chain = NULL;
+                return;
+        }
+
+        while (cur_chain) {
+                int posn;
+                int j;
+                i++;
+                toi_message(TOI_BIO, TOI_VERBOSE, 0, "Restoring chain %d (%p) "
+                                "state, slot %d.", i, cur_chain, slot);
+
+                chain_state = &cur_chain->saved_state[slot];
+
+                posn = chain_state->extent_num;
+
+                cur_chain->blocks.current_extent = cur_chain->blocks.first;
+                cur_chain->blocks.current_offset = chain_state->offset;
+
+                if (i == toi_writer_posn.saved_chain_number[slot]) {
+                        toi_writer_posn.current_chain = cur_chain;
+                        toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                                        "Found current chain.");
+                }
+
+                for (j = 0; j < 4; j++)
+                        if (i == toi_writer_posn.saved_chain_number[j]) {
+                                toi_writer_posn.saved_chain_ptr[j] = cur_chain;
+                                toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                                        "Found saved chain ptr %d (%p) (offset"
+                                        " %d).", j, cur_chain,
+                                        cur_chain->saved_state[j].offset);
+                        }
+
+                if (posn) {
+                        while (--posn)
+                                cur_chain->blocks.current_extent =
+                                        cur_chain->blocks.current_extent->next;
+                } else
+                        cur_chain->blocks.current_extent = NULL;
+
+                cur_chain = cur_chain->next;
+        }
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Done.");
+        if (test_action_state(TOI_LOGALL))
+                dump_block_chains();
+}
+
+/*
+ * Storage needed
+ *
+ * Returns amount of space in the image header required
+ * for the chain data. This ignores the links between
+ * pages, which we factor in when allocating the space.
+ */
+int toi_bio_devinfo_storage_needed(void)
+{
+        int result = sizeof(num_chains);
+        struct toi_bdev_info *chain = prio_chain_head;
+
+        while (chain) {
+                result += metadata_size;
+
+                /* Chain size */
+                result += sizeof(int);
+
+                /* Extents */
+                result += (2 * sizeof(unsigned long) *
+                        chain->blocks.num_extents);
+
+                chain = chain->next;
+        }
+
+        result += 4 * sizeof(int);
+        return result;
+}
+
+static unsigned long chain_pages_used(struct toi_bdev_info *chain)
+{
+        struct hibernate_extent *this = chain->blocks.first;
+        struct hibernate_extent_saved_state *state = &chain->saved_state[3];
+        unsigned long size = 0;
+        int extent_idx = 1;
+
+        if (!state->extent_num) {
+                if (!this)
+                        return 0;
+                else
+                        return chain->blocks.size;
+        }
+
+        while (extent_idx < state->extent_num) {
+                size += (this->end - this->start + 1);
+                this = this->next;
+                extent_idx++;
+        }
+
+        /* We didn't use the one we're sitting on, so don't count it */
+        return size + state->offset - this->start;
+}
+
+void toi_bio_free_unused_storage_chain(struct toi_bdev_info *chain)
+{
+    unsigned long used = chain_pages_used(chain);
+
+    /* Free the storage */
+    unsigned long first_freed = 0;
+
+    if (chain->allocator->bio_allocator_ops->free_unused_storage)
+        first_freed = chain->allocator->bio_allocator_ops->free_unused_storage(chain, used);
+
+    printk(KERN_EMERG "Used %ld blocks in this chain. First extent freed is %lx.\n", used, first_freed);
+
+    /* Adjust / free the extents. */
+    toi_put_extent_chain_from(&chain->blocks, first_freed);
+
+    {
+        struct hibernate_extent *this = chain->blocks.first;
+        while (this) {
+            printk("Extent %lx-%lx.\n", this->start, this->end);
+            this = this->next;
+        }
+    }
+}
+
+/**
+ * toi_serialise_extent_chain - write a chain in the image
+ * @chain:        Chain to write.
+ **/
+static int toi_serialise_extent_chain(struct toi_bdev_info *chain)
+{
+        struct hibernate_extent *this;
+        int ret;
+        int i = 1;
+
+        chain->pages_used = chain_pages_used(chain);
+
+        if (test_action_state(TOI_LOGALL))
+                dump_block_chains();
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Serialising chain (dev_t %lx).",
+                        chain->dev_t);
+        /* Device info -  dev_t, prio, bmap_shift, blocks per page, positions */
+        ret = toiActiveAllocator->rw_header_chunk(WRITE, &toi_blockwriter_ops,
+                        (char *) &chain->uuid, metadata_size);
+        if (ret)
+                return ret;
+
+        /* Num extents */
+        ret = toiActiveAllocator->rw_header_chunk(WRITE, &toi_blockwriter_ops,
+                        (char *) &chain->blocks.num_extents, sizeof(int));
+        if (ret)
+                return ret;
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "%d extents.",
+                        chain->blocks.num_extents);
+
+        this = chain->blocks.first;
+        while (this) {
+                toi_message(TOI_BIO, TOI_VERBOSE, 0, "Extent %d.", i);
+                ret = toiActiveAllocator->rw_header_chunk(WRITE,
+                                &toi_blockwriter_ops,
+                                (char *) this, 2 * sizeof(this->start));
+                if (ret)
+                        return ret;
+                this = this->next;
+                i++;
+        }
+
+        return ret;
+}
+
+int toi_serialise_extent_chains(void)
+{
+        struct toi_bdev_info *this = prio_chain_head;
+        int result;
+
+        /* Write the number of chains */
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Write number of chains (%d)",
+                        num_chains);
+        result = toiActiveAllocator->rw_header_chunk(WRITE,
+                        &toi_blockwriter_ops, (char *) &num_chains,
+                        sizeof(int));
+        if (result)
+                return result;
+
+        /* Then the chains themselves */
+        while (this) {
+                result = toi_serialise_extent_chain(this);
+                if (result)
+                        return result;
+                this = this->next;
+        }
+
+        /*
+         * Finally, the chain we should be on at the start of each
+         * section.
+         */
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Saved chain numbers.");
+        result = toiActiveAllocator->rw_header_chunk(WRITE,
+                        &toi_blockwriter_ops,
+                        (char *) &toi_writer_posn.saved_chain_number[0],
+                        4 * sizeof(int));
+
+        return result;
+}
+
+int toi_register_storage_chain(struct toi_bdev_info *new)
+{
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Inserting chain %p into list.",
+                        new);
+        toi_insert_chain_in_prio_list(new);
+        return 0;
+}
+
+static void free_bdev_info(struct toi_bdev_info *chain)
+{
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Free chain %p.", chain);
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, " - Block extents.");
+        toi_put_extent_chain(&chain->blocks);
+
+        /*
+         * The allocator may need to do more than just free the chains
+         * (swap_free, for example). Don't call from boot kernel.
+         */
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, " - Allocator extents.");
+        if (chain->allocator)
+                chain->allocator->bio_allocator_ops->free_storage(chain);
+
+        /*
+         * Dropping out of reading atomic copy? Need to undo
+         * toi_open_by_devnum.
+         */
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, " - Bdev.");
+        if (chain->bdev && !IS_ERR(chain->bdev) &&
+                        chain->bdev != resume_block_device &&
+                        chain->bdev != header_block_device &&
+                        test_toi_state(TOI_TRYING_TO_RESUME))
+                toi_close_bdev(chain->bdev);
+
+        /* Poison */
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, " - Struct.");
+        toi_kfree(39, chain, sizeof(*chain));
+
+        if (prio_chain_head == chain)
+                prio_chain_head = NULL;
+
+        num_chains--;
+}
+
+void free_all_bdev_info(void)
+{
+        struct toi_bdev_info *this = prio_chain_head;
+
+        while (this) {
+                struct toi_bdev_info *next = this->next;
+                free_bdev_info(this);
+                this = next;
+        }
+
+        memset((char *) &toi_writer_posn, 0, sizeof(toi_writer_posn));
+        prio_chain_head = NULL;
+}
+
+static void set_up_start_position(void)
+{
+        toi_writer_posn.current_chain = prio_chain_head;
+        go_next_page(0, 0);
+}
+
+/**
+ * toi_load_extent_chain - read back a chain saved in the image
+ * @chain:        Chain to load
+ *
+ * The linked list of extents is reconstructed from the disk. chain will point
+ * to the first entry.
+ **/
+int toi_load_extent_chain(int index, int *num_loaded)
+{
+        struct toi_bdev_info *chain = toi_kzalloc(39,
+                        sizeof(struct toi_bdev_info), GFP_ATOMIC);
+        struct hibernate_extent *this, *last = NULL;
+        int i, ret;
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Loading extent chain %d.", index);
+        /* Get dev_t, prio, bmap_shift, blocks per page, positions */
+        ret = toiActiveAllocator->rw_header_chunk_noreadahead(READ, NULL,
+                        (char *) &chain->uuid, metadata_size);
+
+        if (ret) {
+                printk(KERN_ERR "Failed to read the size of extent chain.\n");
+                toi_kfree(39, chain, sizeof(*chain));
+                return 1;
+        }
+
+        toi_bkd.pages_used[index] = chain->pages_used;
+
+        ret = toiActiveAllocator->rw_header_chunk_noreadahead(READ, NULL,
+                        (char *) &chain->blocks.num_extents, sizeof(int));
+        if (ret) {
+                printk(KERN_ERR "Failed to read the size of extent chain.\n");
+                toi_kfree(39, chain, sizeof(*chain));
+                return 1;
+        }
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "%d extents.",
+                        chain->blocks.num_extents);
+
+        for (i = 0; i < chain->blocks.num_extents; i++) {
+                toi_message(TOI_BIO, TOI_VERBOSE, 0, "Extent %d.", i + 1);
+
+                this = toi_kzalloc(2, sizeof(struct hibernate_extent),
+                                TOI_ATOMIC_GFP);
+                if (!this) {
+                        printk(KERN_INFO "Failed to allocate a new extent.\n");
+                        free_bdev_info(chain);
+                        return -ENOMEM;
+                }
+                this->next = NULL;
+                /* Get the next page */
+                ret = toiActiveAllocator->rw_header_chunk_noreadahead(READ,
+                                NULL, (char *) this, 2 * sizeof(this->start));
+                if (ret) {
+                        printk(KERN_INFO "Failed to read an extent.\n");
+                        toi_kfree(2, this, sizeof(struct hibernate_extent));
+                        free_bdev_info(chain);
+                        return 1;
+                }
+
+                if (last)
+                        last->next = this;
+                else {
+                        char b1[32], b2[32], b3[32];
+                        /*
+                         * Open the bdev
+                         */
+                        toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                                "Chain dev_t is %s. Resume dev t is %s. Header"
+                                " bdev_t is %s.\n",
+                                format_dev_t(b1, chain->dev_t),
+                                format_dev_t(b2, resume_dev_t),
+                                format_dev_t(b3, toi_sig_data->header_dev_t));
+
+                        if (chain->dev_t == resume_dev_t)
+                                chain->bdev = resume_block_device;
+                        else if (chain->dev_t == toi_sig_data->header_dev_t)
+                                chain->bdev = header_block_device;
+                        else {
+                                chain->bdev = toi_open_bdev(chain->uuid,
+                                                chain->dev_t, 1);
+                                if (IS_ERR(chain->bdev)) {
+                                        free_bdev_info(chain);
+                                        return -ENODEV;
+                                }
+                        }
+
+                        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Chain bmap shift "
+                                        "is %d and blocks per page is %d.",
+                                        chain->bmap_shift,
+                                        chain->blocks_per_page);
+
+                        chain->blocks.first = this;
+
+                        /*
+                         * Couldn't do this earlier, but can't do
+                         * goto_start now - we may have already used blocks
+                         * in the first chain.
+                         */
+                        chain->blocks.current_extent = this;
+                        chain->blocks.current_offset = this->start;
+
+                        /*
+                         * Can't wait until we've read the whole chain
+                         * before we insert it in the list. We might need
+                         * this chain to read the next page in the header
+                         */
+                        toi_insert_chain_in_prio_list(chain);
+                }
+
+                /*
+                 * We have to wait until 2 extents are loaded before setting up
+                 * properly because if the first extent has only one page, we
+                 * will need to put the position on the second extent. Sounds
+                 * obvious, but it wasn't!
+                 */
+                (*num_loaded)++;
+                if ((*num_loaded) == 2)
+                        set_up_start_position();
+                last = this;
+        }
+
+        /*
+         * Shouldn't get empty chains, but it's not impossible. Link them in so
+         * they get freed properly later.
+         */
+        if (!chain->blocks.num_extents)
+                toi_insert_chain_in_prio_list(chain);
+
+        if (!chain->blocks.current_extent) {
+                chain->blocks.current_extent = chain->blocks.first;
+                if (chain->blocks.current_extent)
+                        chain->blocks.current_offset =
+                                chain->blocks.current_extent->start;
+        }
+        return 0;
+}
+
+int toi_load_extent_chains(void)
+{
+        int result;
+        int to_load;
+        int i;
+        int extents_loaded = 0;
+
+        result = toiActiveAllocator->rw_header_chunk_noreadahead(READ, NULL,
+                        (char *) &to_load,
+                        sizeof(int));
+        if (result)
+                return result;
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "%d chains to read.", to_load);
+
+        for (i = 0; i < to_load; i++) {
+                toi_message(TOI_BIO, TOI_VERBOSE, 0, " >> Loading chain %d/%d.",
+                                i, to_load);
+                result = toi_load_extent_chain(i, &extents_loaded);
+                if (result)
+                        return result;
+        }
+
+        /* If we never got to a second extent, we still need to do this. */
+        if (extents_loaded == 1)
+                set_up_start_position();
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Save chain numbers.");
+        result = toiActiveAllocator->rw_header_chunk_noreadahead(READ,
+                        &toi_blockwriter_ops,
+                        (char *) &toi_writer_posn.saved_chain_number[0],
+                        4 * sizeof(int));
+
+        return result;
+}
+
+static int toi_end_of_stream(int writing, int section_barrier)
+{
+        struct toi_bdev_info *cur_chain = toi_writer_posn.current_chain;
+        int compare_to = next_section[current_stream];
+        struct toi_bdev_info *compare_chain =
+                toi_writer_posn.saved_chain_ptr[compare_to];
+        int compare_offset = compare_chain ?
+                compare_chain->saved_state[compare_to].offset : 0;
+
+        if (!section_barrier)
+                return 0;
+
+        if (!cur_chain)
+                return 1;
+
+        if (cur_chain == compare_chain &&
+            cur_chain->blocks.current_offset == compare_offset) {
+                if (writing) {
+                        if (!current_stream) {
+                                debug_broken_header();
+                                return 1;
+                        }
+                } else {
+                        more_readahead = 0;
+                        toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                                        "Reached the end of stream %d "
+                                        "(not an error).", current_stream);
+                        return 1;
+                }
+        }
+
+        return 0;
+}
+
+/**
+ * go_next_page - skip blocks to the start of the next page
+ * @writing: Whether we're reading or writing the image.
+ *
+ * Go forward one page.
+ **/
+int go_next_page(int writing, int section_barrier)
+{
+        struct toi_bdev_info *cur_chain = toi_writer_posn.current_chain;
+        int max = cur_chain ? cur_chain->blocks_per_page : 1;
+
+        /* Nope. Go foward a page - or maybe two. Don't stripe the header,
+         * so that bad fragmentation doesn't put the extent data containing
+         * the location of the second page out of the first header page.
+         */
+        if (toi_extent_state_next(max, current_stream)) {
+                /* Don't complain if readahead falls off the end */
+                if (writing && section_barrier) {
+                        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Extent state eof. "
+                                "Expected compression ratio too optimistic?");
+                        if (test_action_state(TOI_LOGALL))
+                                dump_block_chains();
+                }
+                toi_message(TOI_BIO, TOI_VERBOSE, 0, "Ran out of extents to "
+                                "read/write. (Not necessarily a fatal error.");
+                return -ENOSPC;
+        }
+
+        return 0;
+}
+
+int devices_of_same_priority(struct toi_bdev_info *this)
+{
+        struct toi_bdev_info *check = prio_chain_head;
+        int i = 0;
+
+        while (check) {
+                if (check->prio == this->prio)
+                        i++;
+                check = check->next;
+        }
+
+        return i;
+}
+
+/**
+ * toi_bio_rw_page - do i/o on the next disk page in the image
+ * @writing: Whether reading or writing.
+ * @page: Page to do i/o on.
+ * @is_readahead: Whether we're doing readahead
+ * @free_group: The group used in allocating the page
+ *
+ * Submit a page for reading or writing, possibly readahead.
+ * Pass the group used in allocating the page as well, as it should
+ * be freed on completion of the bio if we're writing the page.
+ **/
+int toi_bio_rw_page(int writing, struct page *page,
+                int is_readahead, int free_group)
+{
+        int result = toi_end_of_stream(writing, 1);
+        struct toi_bdev_info *dev_info = toi_writer_posn.current_chain;
+
+        if (result) {
+                if (writing)
+                        abort_hibernate(TOI_INSUFFICIENT_STORAGE,
+                                "Insufficient storage for your image.");
+                else
+                        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Seeking to "
+                                "read/write another page when stream has "
+                                "ended.");
+                return -ENOSPC;
+        }
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                        "%s %lx:%ld",
+                        writing ? "Write" : "Read",
+                        dev_info->dev_t, dev_info->blocks.current_offset);
+
+        result = toi_do_io(writing, dev_info->bdev,
+                dev_info->blocks.current_offset << dev_info->bmap_shift,
+                page, is_readahead, 0, free_group);
+
+        /* Ignore the result here - will check end of stream if come in again */
+        go_next_page(writing, 1);
+
+        if (result)
+                printk(KERN_ERR "toi_do_io returned %d.\n", result);
+        return result;
+}
+
+dev_t get_header_dev_t(void)
+{
+        return prio_chain_head->dev_t;
+}
+
+struct block_device *get_header_bdev(void)
+{
+        return prio_chain_head->bdev;
+}
+
+unsigned long get_headerblock(void)
+{
+        return prio_chain_head->blocks.first->start <<
+                prio_chain_head->bmap_shift;
+}
+
+int get_main_pool_phys_params(void)
+{
+        struct toi_bdev_info *this = prio_chain_head;
+        int result;
+
+        while (this) {
+                result = this->allocator->bio_allocator_ops->bmap(this);
+                if (result)
+                        return result;
+                this = this->next;
+        }
+
+        return 0;
+}
+
+static int apply_header_reservation(void)
+{
+        int i;
+
+        if (!header_pages_reserved) {
+                toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                                "No header pages reserved at the moment.");
+                return 0;
+        }
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Applying header reservation.");
+
+        /* Apply header space reservation */
+        toi_extent_state_goto_start();
+
+        for (i = 0; i < header_pages_reserved; i++)
+                if (go_next_page(1, 0))
+                        return -ENOSPC;
+
+        /* The end of header pages will be the start of pageset 2 */
+        toi_extent_state_save(2);
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                        "Finished applying header reservation.");
+        return 0;
+}
+
+static int toi_bio_register_storage(void)
+{
+        int result = 0;
+        struct toi_module_ops *this_module;
+
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                if (!this_module->enabled ||
+                    this_module->type != BIO_ALLOCATOR_MODULE)
+                        continue;
+                toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                                "Registering storage from %s.",
+                                this_module->name);
+                result = this_module->bio_allocator_ops->register_storage();
+                if (result)
+                        break;
+        }
+
+        return result;
+}
+
+void toi_bio_free_unused_storage(void)
+{
+    struct toi_bdev_info *this = prio_chain_head;
+
+    while (this) {
+        toi_bio_free_unused_storage_chain(this);
+        this = this->next;
+    }
+}
+
+int toi_bio_allocate_storage(unsigned long request)
+{
+        struct toi_bdev_info *chain = prio_chain_head;
+        unsigned long to_get = request;
+        unsigned long extra_pages, needed;
+        int no_free = 0;
+
+        if (!chain) {
+                int result = toi_bio_register_storage();
+                toi_message(TOI_BIO, TOI_VERBOSE, 0, "toi_bio_allocate_storage: "
+                        "Registering storage.");
+                if (result)
+                        return 0;
+                chain = prio_chain_head;
+                if (!chain) {
+                        printk("TuxOnIce: No storage was registered.\n");
+                        return 0;
+                }
+        }
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "toi_bio_allocate_storage: "
+                        "Request is %lu pages.", request);
+        extra_pages = DIV_ROUND_UP(request * (sizeof(unsigned long)
+                               + sizeof(int)), PAGE_SIZE);
+        needed = request + extra_pages + header_pages_reserved;
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Adding %lu extra pages and %lu "
+                        "for header => %lu.",
+                        extra_pages, header_pages_reserved, needed);
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Already allocated %lu pages.",
+                        raw_pages_allocd);
+
+        to_get = needed > raw_pages_allocd ? needed - raw_pages_allocd : 0;
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Need to get %lu pages.", to_get);
+
+        if (!to_get)
+                return apply_header_reservation();
+
+        while (to_get && chain) {
+                int num_group = devices_of_same_priority(chain);
+                int divisor = num_group - no_free;
+                int i;
+                unsigned long portion = DIV_ROUND_UP(to_get, divisor);
+                unsigned long got = 0;
+                unsigned long got_this_round = 0;
+                struct toi_bdev_info *top = chain;
+
+                toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                                " Start of loop. To get is %lu. Divisor is %d.",
+                                to_get, divisor);
+                no_free = 0;
+
+                /*
+                 * We're aiming to spread the allocated storage as evenly
+                 * as possible, but we also want to get all the storage we
+                 * can off this priority.
+                 */
+                for (i = 0; i < num_group; i++) {
+                        struct toi_bio_allocator_ops *ops =
+                                chain->allocator->bio_allocator_ops;
+                        toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                                        " Asking for %lu pages from chain %p.",
+                                        portion, chain);
+                        got = ops->allocate_storage(chain, portion);
+                        toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                                        " Got %lu pages from allocator %p.",
+                                        got, chain);
+                        if (!got)
+                                no_free++;
+                        got_this_round += got;
+                        chain = chain->next;
+                }
+                toi_message(TOI_BIO, TOI_VERBOSE, 0, " Loop finished. Got a "
+                                "total of %lu pages from %d allocators.",
+                                got_this_round, divisor - no_free);
+
+                raw_pages_allocd += got_this_round;
+                to_get = needed > raw_pages_allocd ? needed - raw_pages_allocd :
+                        0;
+
+                /*
+                 * If we got anything from chains of this priority and we
+                 * still have storage to allocate, go over this priority
+                 * again.
+                 */
+                if (got_this_round && to_get)
+                        chain = top;
+                else
+                        no_free = 0;
+        }
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Finished allocating. Calling "
+                        "get_main_pool_phys_params");
+        /* Now let swap allocator bmap the pages */
+        get_main_pool_phys_params();
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Done. Reserving header.");
+        return apply_header_reservation();
+}
+
+void toi_bio_chains_post_atomic(struct toi_boot_kernel_data *bkd)
+{
+        int i = 0;
+        struct toi_bdev_info *cur_chain = prio_chain_head;
+
+        while (cur_chain) {
+                cur_chain->pages_used = bkd->pages_used[i];
+                cur_chain = cur_chain->next;
+                i++;
+        }
+}
+
+int toi_bio_chains_debug_info(char *buffer, int size)
+{
+        /* Show what we actually used */
+        struct toi_bdev_info *cur_chain = prio_chain_head;
+        int len = 0;
+
+        while (cur_chain) {
+                len += scnprintf(buffer + len, size - len, "  Used %lu pages "
+                                "from %s.\n", cur_chain->pages_used,
+                                cur_chain->name);
+                cur_chain = cur_chain->next;
+        }
+
+        return len;
+}
+
+void toi_bio_store_inc_image_ptr(struct toi_incremental_image_pointer *ptr)
+{
+    struct toi_bdev_info *this = toi_writer_posn.current_chain,
+                         *cmp = prio_chain_head;
+
+    ptr->save.chain = 1;
+    while (this != cmp) {
+        ptr->save.chain++;
+        cmp = cmp->next;
+    }
+    ptr->save.block = this->blocks.current_offset;
+
+    /* Save the raw info internally for quicker access when updating pointers */
+    ptr->bdev = this->bdev;
+    ptr->block = this->blocks.current_offset << this->bmap_shift;
+}
+
+void toi_bio_restore_inc_image_ptr(struct toi_incremental_image_pointer *ptr)
+{
+    int i = ptr->save.chain - 1;
+    struct toi_bdev_info *this;
+    struct hibernate_extent *hib;
+
+    /* Find chain by stored index */
+    this = prio_chain_head;
+    while (i) {
+        this = this->next;
+        i--;
+    }
+    toi_writer_posn.current_chain = this;
+
+    /* Restore block */
+    this->blocks.current_offset = ptr->save.block;
+
+    /* Find current offset from block number */
+    hib = this->blocks.first;
+
+    while (hib->start > ptr->save.block) {
+        hib = hib->next;
+    }
+
+    this->blocks.last_touched = this->blocks.current_extent = hib;
+}
diff --git a/kernel/power/tuxonice_bio_core.c b/kernel/power/tuxonice_bio_core.c
new file mode 100644
index 000000000..87aa4c96e
--- /dev/null
+++ b/kernel/power/tuxonice_bio_core.c
@@ -0,0 +1,1932 @@
+/*
+ * kernel/power/tuxonice_bio.c
+ *
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * Distributed under GPLv2.
+ *
+ * This file contains block io functions for TuxOnIce. These are
+ * used by the swapwriter and it is planned that they will also
+ * be used by the NFSwriter.
+ *
+ */
+
+#include <linux/blkdev.h>
+#include <linux/syscalls.h>
+#include <linux/suspend.h>
+#include <linux/ctype.h>
+#include <linux/mount.h>
+#include <linux/fs_uuid.h>
+
+#include "tuxonice.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_prepare_image.h"
+#include "tuxonice_bio.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_alloc.h"
+#include "tuxonice_io.h"
+#include "tuxonice_builtin.h"
+#include "tuxonice_bio_internal.h"
+
+#define MEMORY_ONLY 1
+#define THROTTLE_WAIT 2
+
+/* #define MEASURE_MUTEX_CONTENTION */
+#ifndef MEASURE_MUTEX_CONTENTION
+#define my_mutex_lock(index, the_lock) mutex_lock(the_lock)
+#define my_mutex_unlock(index, the_lock) mutex_unlock(the_lock)
+#else
+unsigned long mutex_times[2][2][NR_CPUS];
+#define my_mutex_lock(index, the_lock) do { \
+        int have_mutex; \
+        have_mutex = mutex_trylock(the_lock); \
+        if (!have_mutex) { \
+                mutex_lock(the_lock); \
+                mutex_times[index][0][smp_processor_id()]++; \
+        } else { \
+                mutex_times[index][1][smp_processor_id()]++; \
+        }
+
+#define my_mutex_unlock(index, the_lock) \
+        mutex_unlock(the_lock); \
+} while (0)
+#endif
+
+static int page_idx, reset_idx;
+
+static int target_outstanding_io = 1024;
+static int max_outstanding_writes, max_outstanding_reads;
+
+static struct page *bio_queue_head, *bio_queue_tail;
+static atomic_t toi_bio_queue_size;
+static DEFINE_SPINLOCK(bio_queue_lock);
+
+static int free_mem_throttle, throughput_throttle;
+int more_readahead = 1;
+static struct page *readahead_list_head, *readahead_list_tail;
+
+static struct page *waiting_on;
+
+static atomic_t toi_io_in_progress, toi_io_done;
+static DECLARE_WAIT_QUEUE_HEAD(num_in_progress_wait);
+
+int current_stream;
+/* Not static, so that the allocators can setup and complete
+ * writing the header */
+char *toi_writer_buffer;
+int toi_writer_buffer_posn;
+
+static DEFINE_MUTEX(toi_bio_mutex);
+static DEFINE_MUTEX(toi_bio_readahead_mutex);
+
+static struct task_struct *toi_queue_flusher;
+static int toi_bio_queue_flush_pages(int dedicated_thread);
+
+struct toi_module_ops toi_blockwriter_ops;
+
+struct toi_incremental_image_pointer toi_inc_ptr[2][2];
+
+#define TOTAL_OUTSTANDING_IO (atomic_read(&toi_io_in_progress) + \
+               atomic_read(&toi_bio_queue_size))
+
+unsigned long raw_pages_allocd, header_pages_reserved;
+
+static int toi_rw_buffer(int writing, char *buffer, int buffer_size,
+                int no_readahead);
+
+/**
+ * set_free_mem_throttle - set the point where we pause to avoid oom.
+ *
+ * Initially, this value is zero, but when we first fail to allocate memory,
+ * we set it (plus a buffer) and thereafter throttle i/o once that limit is
+ * reached.
+ **/
+static void set_free_mem_throttle(void)
+{
+        int new_throttle = nr_free_buffer_pages() + 256;
+
+        if (new_throttle > free_mem_throttle)
+                free_mem_throttle = new_throttle;
+}
+
+#define NUM_REASONS 7
+static atomic_t reasons[NUM_REASONS];
+static char *reason_name[NUM_REASONS] = {
+        "readahead not ready",
+        "bio allocation",
+        "synchronous I/O",
+        "toi_bio_get_new_page",
+        "memory low",
+        "readahead buffer allocation",
+        "throughput_throttle",
+};
+
+/* User Specified Parameters. */
+unsigned long resume_firstblock;
+dev_t resume_dev_t;
+struct block_device *resume_block_device;
+static atomic_t resume_bdev_open_count;
+
+struct block_device *header_block_device;
+
+/**
+ * toi_open_bdev: Open a bdev at resume time.
+ *
+ * index: The swap index. May be MAX_SWAPFILES for the resume_dev_t
+ * (the user can have resume= pointing at a swap partition/file that isn't
+ * swapon'd when they hibernate. MAX_SWAPFILES+1 for the first page of the
+ * header. It will be from a swap partition that was enabled when we hibernated,
+ * but we don't know it's real index until we read that first page.
+ * dev_t: The device major/minor.
+ * display_errs: Whether to try to do this quietly.
+ *
+ * We stored a dev_t in the image header. Open the matching device without
+ * requiring /dev/<whatever> in most cases and record the details needed
+ * to close it later and avoid duplicating work.
+ */
+struct block_device *toi_open_bdev(char *uuid, dev_t default_device,
+                int display_errs)
+{
+        struct block_device *bdev;
+        dev_t device = default_device;
+        char buf[32];
+        int retried = 0;
+
+retry:
+        if (uuid) {
+                struct fs_info seek;
+                strncpy((char *) &seek.uuid, uuid, 16);
+                seek.dev_t = 0;
+                seek.last_mount_size = 0;
+                device = blk_lookup_fs_info(&seek);
+                if (!device) {
+                        device = default_device;
+                        printk(KERN_DEBUG "Unable to resolve uuid. Falling back"
+                                        " to dev_t.\n");
+                } else
+                        printk(KERN_DEBUG "Resolved uuid to device %s.\n",
+                                        format_dev_t(buf, device));
+        }
+
+        if (!device) {
+                printk(KERN_ERR "TuxOnIce attempting to open a "
+                                "blank dev_t!\n");
+                dump_stack();
+                return NULL;
+        }
+        bdev = toi_open_by_devnum(device);
+
+        if (IS_ERR(bdev) || !bdev) {
+                if (!retried) {
+                        retried = 1;
+                        wait_for_device_probe();
+                        goto retry;
+                }
+                if (display_errs)
+                        toi_early_boot_message(1, TOI_CONTINUE_REQ,
+                                "Failed to get access to block device "
+                                "\"%x\" (error %d).\n Maybe you need "
+                                "to run mknod and/or lvmsetup in an "
+                                "initrd/ramfs?", device, bdev);
+                return ERR_PTR(-EINVAL);
+        }
+        toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                        "TuxOnIce got bdev %p for dev_t %x.",
+                        bdev, device);
+
+        return bdev;
+}
+
+static void toi_bio_reserve_header_space(unsigned long request)
+{
+        header_pages_reserved = request;
+}
+
+/**
+ * do_bio_wait - wait for some TuxOnIce I/O to complete
+ * @reason: The array index of the reason we're waiting.
+ *
+ * Wait for a particular page of I/O if we're after a particular page.
+ * If we're not after a particular page, wait instead for all in flight
+ * I/O to be completed or for us to have enough free memory to be able
+ * to submit more I/O.
+ *
+ * If we wait, we also update our statistics regarding why we waited.
+ **/
+static void do_bio_wait(int reason)
+{
+        struct page *was_waiting_on = waiting_on;
+
+        /* On SMP, waiting_on can be reset, so we make a copy */
+        if (was_waiting_on) {
+                wait_on_page_locked(was_waiting_on);
+                atomic_inc(&reasons[reason]);
+        } else {
+                atomic_inc(&reasons[reason]);
+
+                wait_event(num_in_progress_wait,
+                        !atomic_read(&toi_io_in_progress) ||
+                        nr_free_buffer_pages() > free_mem_throttle);
+        }
+}
+
+/**
+ * throttle_if_needed - wait for I/O completion if throttle points are reached
+ * @flags: What to check and how to act.
+ *
+ * Check whether we need to wait for some I/O to complete. We always check
+ * whether we have enough memory available, but may also (depending upon
+ * @reason) check if the throughput throttle limit has been reached.
+ **/
+static int throttle_if_needed(int flags)
+{
+        int free_pages = nr_free_buffer_pages();
+
+        /* Getting low on memory and I/O is in progress? */
+        while (unlikely(free_pages < free_mem_throttle) &&
+                        atomic_read(&toi_io_in_progress) &&
+                        !test_result_state(TOI_ABORTED)) {
+                if (!(flags & THROTTLE_WAIT))
+                        return -ENOMEM;
+                do_bio_wait(4);
+                free_pages = nr_free_buffer_pages();
+        }
+
+        while (!(flags & MEMORY_ONLY) && throughput_throttle &&
+                TOTAL_OUTSTANDING_IO >= throughput_throttle &&
+                !test_result_state(TOI_ABORTED)) {
+                int result = toi_bio_queue_flush_pages(0);
+                if (result)
+                        return result;
+                atomic_inc(&reasons[6]);
+                wait_event(num_in_progress_wait,
+                        !atomic_read(&toi_io_in_progress) ||
+                        TOTAL_OUTSTANDING_IO < throughput_throttle);
+        }
+
+        return 0;
+}
+
+/**
+ * update_throughput_throttle - update the raw throughput throttle
+ * @jif_index: The number of times this function has been called.
+ *
+ * This function is called four times per second by the core, and used to limit
+ * the amount of I/O we submit at once, spreading out our waiting through the
+ * whole job and letting userui get an opportunity to do its work.
+ *
+ * We don't start limiting I/O until 1/4s has gone so that we get a
+ * decent sample for our initial limit, and keep updating it because
+ * throughput may vary (on rotating media, eg) with our block number.
+ *
+ * We throttle to 1/10s worth of I/O.
+ **/
+static void update_throughput_throttle(int jif_index)
+{
+        int done = atomic_read(&toi_io_done);
+        throughput_throttle = done * 2 / 5 / jif_index;
+}
+
+/**
+ * toi_finish_all_io - wait for all outstanding i/o to complete
+ *
+ * Flush any queued but unsubmitted I/O and wait for it all to complete.
+ **/
+static int toi_finish_all_io(void)
+{
+        int result = toi_bio_queue_flush_pages(0);
+        toi_bio_queue_flusher_should_finish = 1;
+        wake_up(&toi_io_queue_flusher);
+        wait_event(num_in_progress_wait, !TOTAL_OUTSTANDING_IO);
+        return result;
+}
+
+/**
+ * toi_end_bio - bio completion function.
+ * @bio: bio that has completed.
+ *
+ * Function called by the block driver from interrupt context when I/O is
+ * completed. If we were writing the page, we want to free it and will have
+ * set bio->bi_private to the parameter we should use in telling the page
+ * allocation accounting code what the page was allocated for. If we're
+ * reading the page, it will be in the singly linked list made from
+ * page->private pointers.
+ **/
+static void toi_end_bio(struct bio *bio)
+{
+        struct page *page = bio->bi_io_vec[0].bv_page;
+
+        BUG_ON(bio->bi_error);
+
+        unlock_page(page);
+        bio_put(bio);
+
+        if (waiting_on == page)
+                waiting_on = NULL;
+
+        put_page(page);
+
+        if (bio->bi_private)
+                toi__free_page((int) ((unsigned long) bio->bi_private) , page);
+
+        bio_put(bio);
+
+        atomic_dec(&toi_io_in_progress);
+        atomic_inc(&toi_io_done);
+
+        wake_up(&num_in_progress_wait);
+}
+
+/**
+ * submit - submit BIO request
+ * @writing: READ or WRITE.
+ * @dev: The block device we're using.
+ * @first_block: The first sector we're using.
+ * @page: The page being used for I/O.
+ * @free_group: If writing, the group that was used in allocating the page
+ *         and which will be used in freeing the page from the completion
+ *         routine.
+ *
+ * Based on Patrick Mochell's pmdisk code from long ago: "Straight from the
+ * textbook - allocate and initialize the bio. If we're writing, make sure
+ * the page is marked as dirty. Then submit it and carry on."
+ *
+ * If we're just testing the speed of our own code, we fake having done all
+ * the hard work and all toi_end_bio immediately.
+ **/
+static int submit(int writing, struct block_device *dev, sector_t first_block,
+                struct page *page, int free_group)
+{
+        struct bio *bio = NULL;
+        int cur_outstanding_io, result;
+
+        /*
+         * Shouldn't throttle if reading - can deadlock in the single
+         * threaded case as pages are only freed when we use the
+         * readahead.
+         */
+        if (writing) {
+                result = throttle_if_needed(MEMORY_ONLY | THROTTLE_WAIT);
+                if (result)
+                        return result;
+        }
+
+        while (!bio) {
+                bio = bio_alloc(TOI_ATOMIC_GFP, 1);
+                if (!bio) {
+                        set_free_mem_throttle();
+                        do_bio_wait(1);
+                }
+        }
+
+        bio->bi_bdev = dev;
+        bio->bi_iter.bi_sector = first_block;
+        bio->bi_private = (void *) ((unsigned long) free_group);
+        bio->bi_end_io = toi_end_bio;
+        bio_set_flag(bio, BIO_TOI);
+
+        if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
+                printk(KERN_DEBUG "ERROR: adding page to bio at %lld\n",
+                                (unsigned long long) first_block);
+                bio_put(bio);
+                return -EFAULT;
+        }
+
+        bio_get(bio);
+
+        cur_outstanding_io = atomic_add_return(1, &toi_io_in_progress);
+        if (writing) {
+                if (cur_outstanding_io > max_outstanding_writes)
+                        max_outstanding_writes = cur_outstanding_io;
+        } else {
+                if (cur_outstanding_io > max_outstanding_reads)
+                        max_outstanding_reads = cur_outstanding_io;
+        }
+
+        /* Still read the header! */
+        if (unlikely(test_action_state(TOI_TEST_BIO) && writing)) {
+                /* Fake having done the hard work */
+                bio->bi_error = 0;
+                toi_end_bio(bio);
+        } else
+                submit_bio(writing | REQ_SYNC, bio);
+
+        return 0;
+}
+
+/**
+ * toi_do_io: Prepare to do some i/o on a page and submit or batch it.
+ *
+ * @writing: Whether reading or writing.
+ * @bdev: The block device which we're using.
+ * @block0: The first sector we're reading or writing.
+ * @page: The page on which I/O is being done.
+ * @readahead_index: If doing readahead, the index (reset this flag when done).
+ * @syncio: Whether the i/o is being done synchronously.
+ *
+ * Prepare and start a read or write operation.
+ *
+ * Note that we always work with our own page. If writing, we might be given a
+ * compression buffer that will immediately be used to start compressing the
+ * next page. For reading, we do readahead and therefore don't know the final
+ * address where the data needs to go.
+ **/
+int toi_do_io(int writing, struct block_device *bdev, long block0,
+        struct page *page, int is_readahead, int syncio, int free_group)
+{
+        page->private = 0;
+
+        /* Do here so we don't race against toi_bio_get_next_page_read */
+        lock_page(page);
+
+        if (is_readahead) {
+                if (readahead_list_head)
+                        readahead_list_tail->private = (unsigned long) page;
+                else
+                        readahead_list_head = page;
+
+                readahead_list_tail = page;
+        }
+
+        /* Done before submitting to avoid races. */
+        if (syncio)
+                waiting_on = page;
+
+        /* Submit the page */
+        get_page(page);
+
+        if (submit(writing, bdev, block0, page, free_group))
+                return -EFAULT;
+
+        if (syncio)
+                do_bio_wait(2);
+
+        return 0;
+}
+
+/**
+ * toi_bdev_page_io - simpler interface to do directly i/o on a single page
+ * @writing: Whether reading or writing.
+ * @bdev: Block device on which we're operating.
+ * @pos: Sector at which page to read or write starts.
+ * @page: Page to be read/written.
+ *
+ * A simple interface to submit a page of I/O and wait for its completion.
+ * The caller must free the page used.
+ **/
+static int toi_bdev_page_io(int writing, struct block_device *bdev,
+                long pos, struct page *page)
+{
+        return toi_do_io(writing, bdev, pos, page, 0, 1, 0);
+}
+
+/**
+ * toi_bio_memory_needed - report the amount of memory needed for block i/o
+ *
+ * We want to have at least enough memory so as to have target_outstanding_io
+ * or more transactions on the fly at once. If we can do more, fine.
+ **/
+static int toi_bio_memory_needed(void)
+{
+        return target_outstanding_io * (PAGE_SIZE + sizeof(struct request) +
+                                sizeof(struct bio));
+}
+
+/**
+ * toi_bio_print_debug_stats - put out debugging info in the buffer provided
+ * @buffer: A buffer of size @size into which text should be placed.
+ * @size: The size of @buffer.
+ *
+ * Fill a buffer with debugging info. This is used for both our debug_info sysfs
+ * entry and for recording the same info in dmesg.
+ **/
+static int toi_bio_print_debug_stats(char *buffer, int size)
+{
+        int len = 0;
+
+        if (toiActiveAllocator != &toi_blockwriter_ops) {
+                len = scnprintf(buffer, size,
+                                "- Block I/O inactive.\n");
+                return len;
+        }
+
+        len = scnprintf(buffer, size, "- Block I/O active.\n");
+
+        len += toi_bio_chains_debug_info(buffer + len, size - len);
+
+        len += scnprintf(buffer + len, size - len,
+                        "- Max outstanding reads %d. Max writes %d.\n",
+                        max_outstanding_reads, max_outstanding_writes);
+
+        len += scnprintf(buffer + len, size - len,
+                "  Memory_needed: %d x (%lu + %u + %u) = %d bytes.\n",
+                target_outstanding_io,
+                PAGE_SIZE, (unsigned int) sizeof(struct request),
+                (unsigned int) sizeof(struct bio), toi_bio_memory_needed());
+
+#ifdef MEASURE_MUTEX_CONTENTION
+        {
+        int i;
+
+        len += scnprintf(buffer + len, size - len,
+                "  Mutex contention while reading:\n  Contended      Free\n");
+
+        for_each_online_cpu(i)
+                len += scnprintf(buffer + len, size - len,
+                "  %9lu %9lu\n",
+                mutex_times[0][0][i], mutex_times[0][1][i]);
+
+        len += scnprintf(buffer + len, size - len,
+                "  Mutex contention while writing:\n  Contended      Free\n");
+
+        for_each_online_cpu(i)
+                len += scnprintf(buffer + len, size - len,
+                "  %9lu %9lu\n",
+                mutex_times[1][0][i], mutex_times[1][1][i]);
+
+        }
+#endif
+
+        return len + scnprintf(buffer + len, size - len,
+                "  Free mem throttle point reached %d.\n", free_mem_throttle);
+}
+
+static int total_header_bytes;
+static int unowned;
+
+void debug_broken_header(void)
+{
+        printk(KERN_DEBUG "Image header too big for size allocated!\n");
+        print_toi_header_storage_for_modules();
+        printk(KERN_DEBUG "Page flags : %d.\n", toi_pageflags_space_needed());
+        printk(KERN_DEBUG "toi_header : %zu.\n", sizeof(struct toi_header));
+        printk(KERN_DEBUG "Total unowned : %d.\n", unowned);
+        printk(KERN_DEBUG "Total used : %d (%ld pages).\n", total_header_bytes,
+                        DIV_ROUND_UP(total_header_bytes, PAGE_SIZE));
+        printk(KERN_DEBUG "Space needed now : %ld.\n",
+                        get_header_storage_needed());
+        dump_block_chains();
+        abort_hibernate(TOI_HEADER_TOO_BIG, "Header reservation too small.");
+}
+
+static int toi_bio_update_previous_inc_img_ptr(int stream)
+{
+    int result;
+    char * buffer = (char *) toi_get_zeroed_page(12, TOI_ATOMIC_GFP);
+    struct page *page;
+    struct toi_incremental_image_pointer *prev, *this;
+
+    prev = &toi_inc_ptr[stream][0];
+    this = &toi_inc_ptr[stream][1];
+
+    if (!buffer) {
+        // We're at the start of writing a pageset. Memory should not be that scarce.
+        return -ENOMEM;
+    }
+
+    page = virt_to_page(buffer);
+    result = toi_do_io(READ, prev->bdev, prev->block, page, 0, 1, 0);
+
+    if (result)
+        goto out;
+
+    memcpy(buffer, (char *) this, sizeof(this->save));
+
+    result = toi_do_io(WRITE, prev->bdev, prev->block, page, 0, 0, 12);
+
+    // If the IO is successfully submitted (!result), the page will be freed
+    // asynchronously on completion.
+out:
+    if (result)
+        toi__free_page(12, virt_to_page(buffer));
+    return result;
+}
+
+/**
+ * toi_rw_init_incremental - incremental image part of setting up to write new section
+ */
+static int toi_write_init_incremental(int stream)
+{
+    int result = 0;
+
+    // Remember the location of this block so we can link to it.
+    toi_bio_store_inc_image_ptr(&toi_inc_ptr[stream][1]);
+
+    // Update the pointer at the start of the last pageset with the same stream number.
+    result = toi_bio_update_previous_inc_img_ptr(stream);
+    if (result)
+        return result;
+
+    // Move the current to the previous slot.
+    memcpy(&toi_inc_ptr[stream][0], &toi_inc_ptr[stream][1], sizeof(toi_inc_ptr[stream][1]));
+
+    // Store a blank pointer at the start of this incremental pageset
+    memset(&toi_inc_ptr[stream][1], 0, sizeof(toi_inc_ptr[stream][1]));
+    result = toi_rw_buffer(WRITE, (char *) &toi_inc_ptr[stream][1], sizeof(toi_inc_ptr[stream][1]), 0);
+    if (result)
+        return result;
+
+    // Serialise extent chains if this is an incremental pageset
+    return toi_serialise_extent_chains();
+}
+
+/**
+ * toi_read_init_incremental - incremental image part of setting up to read new section
+ */
+static int toi_read_init_incremental(int stream)
+{
+    int result;
+
+    // Set our position to the start of the next pageset
+    toi_bio_restore_inc_image_ptr(&toi_inc_ptr[stream][1]);
+
+    // Read the start of the next incremental pageset (if any)
+    result = toi_rw_buffer(READ, (char *) &toi_inc_ptr[stream][1], sizeof(toi_inc_ptr[stream][1]), 0);
+
+    if (!result)
+        result = toi_load_extent_chains();
+
+    return result;
+}
+
+/**
+ * toi_rw_init - prepare to read or write a stream in the image
+ * @writing: Whether reading or writing.
+ * @stream number: Section of the image being processed.
+ *
+ * Prepare to read or write a section ('stream') in the image.
+ **/
+static int toi_rw_init(int writing, int stream_number)
+{
+        if (stream_number)
+                toi_extent_state_restore(stream_number);
+        else
+                toi_extent_state_goto_start();
+
+        if (writing) {
+                reset_idx = 0;
+                if (!current_stream)
+                        page_idx = 0;
+        } else {
+                reset_idx = 1;
+        }
+
+        atomic_set(&toi_io_done, 0);
+        if (!toi_writer_buffer)
+                toi_writer_buffer = (char *) toi_get_zeroed_page(11,
+                                TOI_ATOMIC_GFP);
+        toi_writer_buffer_posn = writing ? 0 : PAGE_SIZE;
+
+        current_stream = stream_number;
+
+        more_readahead = 1;
+
+        if (test_result_state(TOI_KEPT_IMAGE)) {
+            int result;
+
+            if (writing) {
+                result = toi_write_init_incremental(stream_number);
+            } else {
+                result = toi_read_init_incremental(stream_number);
+            }
+
+            if (result)
+                return result;
+        }
+
+        return toi_writer_buffer ? 0 : -ENOMEM;
+}
+
+/**
+ * toi_bio_queue_write - queue a page for writing
+ * @full_buffer: Pointer to a page to be queued
+ *
+ * Add a page to the queue to be submitted. If we're the queue flusher,
+ * we'll do this once we've dropped toi_bio_mutex, so other threads can
+ * continue to submit I/O while we're on the slow path doing the actual
+ * submission.
+ **/
+static void toi_bio_queue_write(char **full_buffer)
+{
+        struct page *page = virt_to_page(*full_buffer);
+        unsigned long flags;
+
+        *full_buffer = NULL;
+        page->private = 0;
+
+        spin_lock_irqsave(&bio_queue_lock, flags);
+        if (!bio_queue_head)
+                bio_queue_head = page;
+        else
+                bio_queue_tail->private = (unsigned long) page;
+
+        bio_queue_tail = page;
+        atomic_inc(&toi_bio_queue_size);
+
+        spin_unlock_irqrestore(&bio_queue_lock, flags);
+        wake_up(&toi_io_queue_flusher);
+}
+
+/**
+ * toi_rw_cleanup - Cleanup after i/o.
+ * @writing: Whether we were reading or writing.
+ *
+ * Flush all I/O and clean everything up after reading or writing a
+ * section of the image.
+ **/
+static int toi_rw_cleanup(int writing)
+{
+        int i, result = 0;
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "toi_rw_cleanup.");
+        if (writing) {
+                if (toi_writer_buffer_posn && !test_result_state(TOI_ABORTED))
+                        toi_bio_queue_write(&toi_writer_buffer);
+
+                while (bio_queue_head && !result)
+                        result = toi_bio_queue_flush_pages(0);
+
+                if (result)
+                        return result;
+
+                if (current_stream == 2)
+                        toi_extent_state_save(1);
+                else if (current_stream == 1)
+                        toi_extent_state_save(3);
+        }
+
+        result = toi_finish_all_io();
+
+        while (readahead_list_head) {
+                void *next = (void *) readahead_list_head->private;
+                toi__free_page(12, readahead_list_head);
+                readahead_list_head = next;
+        }
+
+        readahead_list_tail = NULL;
+
+        if (!current_stream)
+                return result;
+
+        for (i = 0; i < NUM_REASONS; i++) {
+                if (!atomic_read(&reasons[i]))
+                        continue;
+                printk(KERN_DEBUG "Waited for i/o due to %s %d times.\n",
+                                reason_name[i], atomic_read(&reasons[i]));
+                atomic_set(&reasons[i], 0);
+        }
+
+        current_stream = 0;
+        return result;
+}
+
+/**
+ * toi_start_one_readahead - start one page of readahead
+ * @dedicated_thread: Is this a thread dedicated to doing readahead?
+ *
+ * Start one new page of readahead. If this is being called by a thread
+ * whose only just is to submit readahead, don't quit because we failed
+ * to allocate a page.
+ **/
+static int toi_start_one_readahead(int dedicated_thread)
+{
+        char *buffer = NULL;
+        int oom = 0, result;
+
+        result = throttle_if_needed(dedicated_thread ? THROTTLE_WAIT : 0);
+        if (result) {
+            printk("toi_start_one_readahead: throttle_if_needed returned %d.\n", result);
+            return result;
+        }
+
+        mutex_lock(&toi_bio_readahead_mutex);
+
+        while (!buffer) {
+                buffer = (char *) toi_get_zeroed_page(12,
+                                TOI_ATOMIC_GFP);
+                if (!buffer) {
+                        if (oom && !dedicated_thread) {
+                                mutex_unlock(&toi_bio_readahead_mutex);
+                                printk("toi_start_one_readahead: oom and !dedicated thread %d.\n", result);
+                                return -ENOMEM;
+                        }
+
+                        oom = 1;
+                        set_free_mem_throttle();
+                        do_bio_wait(5);
+                }
+        }
+
+        result = toi_bio_rw_page(READ, virt_to_page(buffer), 1, 0);
+        if (result) {
+            printk("toi_start_one_readahead: toi_bio_rw_page returned %d.\n", result);
+        }
+        if (result == -ENOSPC)
+                toi__free_page(12, virt_to_page(buffer));
+        mutex_unlock(&toi_bio_readahead_mutex);
+        if (result) {
+                if (result == -ENOSPC)
+                        toi_message(TOI_BIO, TOI_VERBOSE, 0,
+                                        "Last readahead page submitted.");
+                else
+                        printk(KERN_DEBUG "toi_bio_rw_page returned %d.\n",
+                                        result);
+        }
+        return result;
+}
+
+/**
+ * toi_start_new_readahead - start new readahead
+ * @dedicated_thread: Are we dedicated to this task?
+ *
+ * Start readahead of image pages.
+ *
+ * We can be called as a thread dedicated to this task (may be helpful on
+ * systems with lots of CPUs), in which case we don't exit until there's no
+ * more readahead.
+ *
+ * If this is not called by a dedicated thread, we top up our queue until
+ * there's no more readahead to submit, we've submitted the number given
+ * in target_outstanding_io or the number in progress exceeds the target
+ * outstanding I/O value.
+ *
+ * No mutex needed because this is only ever called by the first cpu.
+ **/
+static int toi_start_new_readahead(int dedicated_thread)
+{
+        int last_result, num_submitted = 0;
+
+        /* Start a new readahead? */
+        if (!more_readahead)
+                return 0;
+
+        do {
+                last_result = toi_start_one_readahead(dedicated_thread);
+
+                if (last_result) {
+                        if (last_result == -ENOMEM || last_result == -ENOSPC)
+                                return 0;
+
+                        printk(KERN_DEBUG
+                                "Begin read chunk returned %d.\n",
+                                last_result);
+                } else
+                        num_submitted++;
+
+        } while (more_readahead && !last_result &&
+                 (dedicated_thread ||
+                  (num_submitted < target_outstanding_io &&
+                   atomic_read(&toi_io_in_progress) < target_outstanding_io)));
+
+        return last_result;
+}
+
+/**
+ * bio_io_flusher - start the dedicated I/O flushing routine
+ * @writing: Whether we're writing the image.
+ **/
+static int bio_io_flusher(int writing)
+{
+
+        if (writing)
+                return toi_bio_queue_flush_pages(1);
+        else
+                return toi_start_new_readahead(1);
+}
+
+/**
+ * toi_bio_get_next_page_read - read a disk page, perhaps with readahead
+ * @no_readahead: Whether we can use readahead
+ *
+ * Read a page from disk, submitting readahead and cleaning up finished i/o
+ * while we wait for the page we're after.
+ **/
+static int toi_bio_get_next_page_read(int no_readahead)
+{
+        char *virt;
+        struct page *old_readahead_list_head;
+
+        /*
+         * When reading the second page of the header, we have to
+         * delay submitting the read until after we've gotten the
+         * extents out of the first page.
+         */
+        if (unlikely(no_readahead)) {
+            int result = toi_start_one_readahead(0);
+            if (result) {
+                printk(KERN_EMERG "No readahead and toi_start_one_readahead "
+                        "returned non-zero.\n");
+                return -EIO;
+            }
+        }
+
+        if (unlikely(!readahead_list_head)) {
+                /*
+                 * If the last page finishes exactly on the page
+                 * boundary, we will be called one extra time and
+                 * have no data to return. In this case, we should
+                 * not BUG(), like we used to!
+                 */
+                if (!more_readahead) {
+                        printk(KERN_EMERG "No more readahead.\n");
+                        return -ENOSPC;
+                }
+                if (unlikely(toi_start_one_readahead(0))) {
+                        printk(KERN_EMERG "No readahead and "
+                         "toi_start_one_readahead returned non-zero.\n");
+                        return -EIO;
+                }
+        }
+
+        if (PageLocked(readahead_list_head)) {
+                waiting_on = readahead_list_head;
+                do_bio_wait(0);
+        }
+
+        virt = page_address(readahead_list_head);
+        memcpy(toi_writer_buffer, virt, PAGE_SIZE);
+        
+        mutex_lock(&toi_bio_readahead_mutex);
+        old_readahead_list_head = readahead_list_head;
+        readahead_list_head = (struct page *) readahead_list_head->private;
+        mutex_unlock(&toi_bio_readahead_mutex);
+        toi__free_page(12, old_readahead_list_head);
+        return 0;
+}
+
+/**
+ * toi_bio_queue_flush_pages - flush the queue of pages queued for writing
+ * @dedicated_thread: Whether we're a dedicated thread
+ *
+ * Flush the queue of pages ready to be written to disk.
+ *
+ * If we're a dedicated thread, stay in here until told to leave,
+ * sleeping in wait_event.
+ *
+ * The first thread is normally the only one to come in here. Another
+ * thread can enter this routine too, though, via throttle_if_needed.
+ * Since that's the case, we must be careful to only have one thread
+ * doing this work at a time. Otherwise we have a race and could save
+ * pages out of order.
+ *
+ * If an error occurs, free all remaining pages without submitting them
+ * for I/O.
+ **/
+
+int toi_bio_queue_flush_pages(int dedicated_thread)
+{
+        unsigned long flags;
+        int result = 0;
+        static DEFINE_MUTEX(busy);
+
+        if (!mutex_trylock(&busy))
+                return 0;
+
+top:
+        spin_lock_irqsave(&bio_queue_lock, flags);
+        while (bio_queue_head) {
+                struct page *page = bio_queue_head;
+                bio_queue_head = (struct page *) page->private;
+                if (bio_queue_tail == page)
+                        bio_queue_tail = NULL;
+                atomic_dec(&toi_bio_queue_size);
+                spin_unlock_irqrestore(&bio_queue_lock, flags);
+
+                /* Don't generate more error messages if already had one */
+                if (!result)
+                        result = toi_bio_rw_page(WRITE, page, 0, 11);
+                /*
+                 * If writing the page failed, don't drop out.
+                 * Flush the rest of the queue too.
+                 */
+                if (result)
+                        toi__free_page(11 , page);
+                spin_lock_irqsave(&bio_queue_lock, flags);
+        }
+        spin_unlock_irqrestore(&bio_queue_lock, flags);
+
+        if (dedicated_thread) {
+                wait_event(toi_io_queue_flusher, bio_queue_head ||
+                                toi_bio_queue_flusher_should_finish);
+                if (likely(!toi_bio_queue_flusher_should_finish))
+                        goto top;
+                toi_bio_queue_flusher_should_finish = 0;
+        }
+
+        mutex_unlock(&busy);
+        return result;
+}
+
+/**
+ * toi_bio_get_new_page - get a new page for I/O
+ * @full_buffer: Pointer to a page to allocate.
+ **/
+static int toi_bio_get_new_page(char **full_buffer)
+{
+        int result = throttle_if_needed(THROTTLE_WAIT);
+        if (result)
+                return result;
+
+        while (!*full_buffer) {
+                *full_buffer = (char *) toi_get_zeroed_page(11, TOI_ATOMIC_GFP);
+                if (!*full_buffer) {
+                        set_free_mem_throttle();
+                        do_bio_wait(3);
+                }
+        }
+
+        return 0;
+}
+
+/**
+ * toi_rw_buffer - combine smaller buffers into PAGE_SIZE I/O
+ * @writing:                Bool - whether writing (or reading).
+ * @buffer:                The start of the buffer to write or fill.
+ * @buffer_size:        The size of the buffer to write or fill.
+ * @no_readahead:        Don't try to start readhead (when getting extents).
+ **/
+static int toi_rw_buffer(int writing, char *buffer, int buffer_size,
+                int no_readahead)
+{
+        int bytes_left = buffer_size, result = 0;
+
+        while (bytes_left) {
+                char *source_start = buffer + buffer_size - bytes_left;
+                char *dest_start = toi_writer_buffer + toi_writer_buffer_posn;
+                int capacity = PAGE_SIZE - toi_writer_buffer_posn;
+                char *to = writing ? dest_start : source_start;
+                char *from = writing ? source_start : dest_start;
+
+                if (bytes_left <= capacity) {
+                        memcpy(to, from, bytes_left);
+                        toi_writer_buffer_posn += bytes_left;
+                        return 0;
+                }
+
+                /* Complete this page and start a new one */
+                memcpy(to, from, capacity);
+                bytes_left -= capacity;
+
+                if (!writing) {
+                        /*
+                         * Perform actual I/O:
+                         * read readahead_list_head into toi_writer_buffer
+                         */
+                        int result = toi_bio_get_next_page_read(no_readahead);
+                        if (result && bytes_left) {
+                                printk("toi_bio_get_next_page_read "
+                                        "returned %d. Expecting to read %d bytes.\n", result, bytes_left);
+                                return result;
+                        }
+                } else {
+                        toi_bio_queue_write(&toi_writer_buffer);
+                        result = toi_bio_get_new_page(&toi_writer_buffer);
+                        if (result) {
+                                printk(KERN_ERR "toi_bio_get_new_page returned "
+                                                "%d.\n", result);
+                                return result;
+                        }
+                }
+
+                toi_writer_buffer_posn = 0;
+                toi_cond_pause(0, NULL);
+        }
+
+        return 0;
+}
+
+/**
+ * toi_bio_read_page - read a page of the image
+ * @pfn:                The pfn where the data belongs.
+ * @buffer_page:        The page containing the (possibly compressed) data.
+ * @buf_size:                The number of bytes on @buffer_page used (PAGE_SIZE).
+ *
+ * Read a (possibly compressed) page from the image, into buffer_page,
+ * returning its pfn and the buffer size.
+ **/
+static int toi_bio_read_page(unsigned long *pfn, int buf_type,
+                void *buffer_page, unsigned int *buf_size)
+{
+        int result = 0;
+        int this_idx;
+        char *buffer_virt = TOI_MAP(buf_type, buffer_page);
+
+        /*
+         * Only call start_new_readahead if we don't have a dedicated thread
+         * and we're the queue flusher.
+         */
+        if (current == toi_queue_flusher && more_readahead &&
+                        !test_action_state(TOI_NO_READAHEAD)) {
+                int result2 = toi_start_new_readahead(0);
+                if (result2) {
+                        printk(KERN_DEBUG "Queue flusher and "
+                         "toi_start_one_readahead returned non-zero.\n");
+                        result = -EIO;
+                        goto out;
+                }
+        }
+
+        my_mutex_lock(0, &toi_bio_mutex);
+
+        /*
+         * Structure in the image:
+         *        [destination pfn|page size|page data]
+         * buf_size is PAGE_SIZE
+         * We can validly find there's nothing to read in a multithreaded
+         * situation.
+         */
+        if (toi_rw_buffer(READ, (char *) &this_idx, sizeof(int), 0) ||
+            toi_rw_buffer(READ, (char *) pfn, sizeof(unsigned long), 0) ||
+            toi_rw_buffer(READ, (char *) buf_size, sizeof(int), 0) ||
+            toi_rw_buffer(READ, buffer_virt, *buf_size, 0)) {
+                result = -ENODATA;
+                goto out_unlock;
+        }
+
+        if (reset_idx) {
+                page_idx = this_idx;
+                reset_idx = 0;
+        } else {
+                page_idx++;
+                if (!this_idx)
+                        result = -ENODATA;
+                else if (page_idx != this_idx)
+                        printk(KERN_ERR "Got page index %d, expected %d.\n",
+                                        this_idx, page_idx);
+        }
+
+out_unlock:
+        my_mutex_unlock(0, &toi_bio_mutex);
+out:
+        TOI_UNMAP(buf_type, buffer_page);
+        return result;
+}
+
+/**
+ * toi_bio_write_page - write a page of the image
+ * @pfn:                The pfn where the data belongs.
+ * @buffer_page:        The page containing the (possibly compressed) data.
+ * @buf_size:        The number of bytes on @buffer_page used.
+ *
+ * Write a (possibly compressed) page to the image from the buffer, together
+ * with it's index and buffer size.
+ **/
+static int toi_bio_write_page(unsigned long pfn, int buf_type,
+                void *buffer_page, unsigned int buf_size)
+{
+        char *buffer_virt;
+        int result = 0, result2 = 0;
+
+        if (unlikely(test_action_state(TOI_TEST_FILTER_SPEED)))
+                return 0;
+
+        my_mutex_lock(1, &toi_bio_mutex);
+
+        if (test_result_state(TOI_ABORTED)) {
+                my_mutex_unlock(1, &toi_bio_mutex);
+                return 0;
+        }
+
+        buffer_virt = TOI_MAP(buf_type, buffer_page);
+        page_idx++;
+
+        /*
+         * Structure in the image:
+         *        [destination pfn|page size|page data]
+         * buf_size is PAGE_SIZE
+         */
+        if (toi_rw_buffer(WRITE, (char *) &page_idx, sizeof(int), 0) ||
+            toi_rw_buffer(WRITE, (char *) &pfn, sizeof(unsigned long), 0) ||
+            toi_rw_buffer(WRITE, (char *) &buf_size, sizeof(int), 0) ||
+            toi_rw_buffer(WRITE, buffer_virt, buf_size, 0)) {
+                printk(KERN_DEBUG "toi_rw_buffer returned non-zero to "
+                                "toi_bio_write_page.\n");
+                result = -EIO;
+        }
+
+        TOI_UNMAP(buf_type, buffer_page);
+        my_mutex_unlock(1, &toi_bio_mutex);
+
+        if (current == toi_queue_flusher)
+                result2 = toi_bio_queue_flush_pages(0);
+
+        return result ? result : result2;
+}
+
+/**
+ * _toi_rw_header_chunk - read or write a portion of the image header
+ * @writing:                Whether reading or writing.
+ * @owner:                The module for which we're writing.
+ *                        Used for confirming that modules
+ *                        don't use more header space than they asked for.
+ * @buffer:                Address of the data to write.
+ * @buffer_size:        Size of the data buffer.
+ * @no_readahead:        Don't try to start readhead (when getting extents).
+ *
+ * Perform PAGE_SIZE I/O. Start readahead if needed.
+ **/
+static int _toi_rw_header_chunk(int writing, struct toi_module_ops *owner,
+                char *buffer, int buffer_size, int no_readahead)
+{
+        int result = 0;
+
+        if (owner) {
+                owner->header_used += buffer_size;
+                toi_message(TOI_HEADER, TOI_LOW, 1,
+                        "Header: %s : %d bytes (%d/%d) from offset %d.",
+                        owner->name,
+                        buffer_size, owner->header_used,
+                        owner->header_requested,
+                        toi_writer_buffer_posn);
+                if (owner->header_used > owner->header_requested && writing) {
+                        printk(KERN_EMERG "TuxOnIce module %s is using more "
+                                "header space (%u) than it requested (%u).\n",
+                                owner->name,
+                                owner->header_used,
+                                owner->header_requested);
+                        return buffer_size;
+                }
+        } else {
+                unowned += buffer_size;
+                toi_message(TOI_HEADER, TOI_LOW, 1,
+                        "Header: (No owner): %d bytes (%d total so far) from "
+                        "offset %d.", buffer_size, unowned,
+                        toi_writer_buffer_posn);
+        }
+
+        if (!writing && !no_readahead && more_readahead) {
+                result = toi_start_new_readahead(0);
+                toi_message(TOI_BIO, TOI_VERBOSE, 0, "Start new readahead "
+                                "returned %d.", result);
+        }
+
+        if (!result) {
+                result = toi_rw_buffer(writing, buffer, buffer_size,
+                                no_readahead);
+                toi_message(TOI_BIO, TOI_VERBOSE, 0, "rw_buffer returned "
+                                "%d.", result);
+        }
+
+        total_header_bytes += buffer_size;
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "_toi_rw_header_chunk returning "
+                        "%d.", result);
+        return result;
+}
+
+static int toi_rw_header_chunk(int writing, struct toi_module_ops *owner,
+                char *buffer, int size)
+{
+        return _toi_rw_header_chunk(writing, owner, buffer, size, 1);
+}
+
+static int toi_rw_header_chunk_noreadahead(int writing,
+                struct toi_module_ops *owner, char *buffer, int size)
+{
+        return _toi_rw_header_chunk(writing, owner, buffer, size, 1);
+}
+
+/**
+ * toi_bio_storage_needed - get the amount of storage needed for my fns
+ **/
+static int toi_bio_storage_needed(void)
+{
+        return sizeof(int) + PAGE_SIZE + toi_bio_devinfo_storage_needed();
+}
+
+/**
+ * toi_bio_save_config_info - save block I/O config to image header
+ * @buf:        PAGE_SIZE'd buffer into which data should be saved.
+ **/
+static int toi_bio_save_config_info(char *buf)
+{
+        int *ints = (int *) buf;
+        ints[0] = target_outstanding_io;
+        return sizeof(int);
+}
+
+/**
+ * toi_bio_load_config_info - restore block I/O config
+ * @buf:        Data to be reloaded.
+ * @size:        Size of the buffer saved.
+ **/
+static void toi_bio_load_config_info(char *buf, int size)
+{
+        int *ints = (int *) buf;
+        target_outstanding_io  = ints[0];
+}
+
+void close_resume_dev_t(int force)
+{
+        if (!resume_block_device)
+                return;
+
+        if (force)
+                atomic_set(&resume_bdev_open_count, 0);
+        else
+                atomic_dec(&resume_bdev_open_count);
+
+        if (!atomic_read(&resume_bdev_open_count)) {
+                toi_close_bdev(resume_block_device);
+                resume_block_device = NULL;
+        }
+}
+
+int open_resume_dev_t(int force, int quiet)
+{
+        if (force) {
+                close_resume_dev_t(1);
+                atomic_set(&resume_bdev_open_count, 1);
+        } else
+                atomic_inc(&resume_bdev_open_count);
+
+        if (resume_block_device)
+                return 0;
+
+        resume_block_device = toi_open_bdev(NULL, resume_dev_t, 0);
+        if (IS_ERR(resume_block_device)) {
+                if (!quiet)
+                        toi_early_boot_message(1, TOI_CONTINUE_REQ,
+                                "Failed to open device %x, where"
+                                " the header should be found.",
+                                resume_dev_t);
+                resume_block_device = NULL;
+                atomic_set(&resume_bdev_open_count, 0);
+                return 1;
+        }
+
+        return 0;
+}
+
+/**
+ * toi_bio_initialise - initialise bio code at start of some action
+ * @starting_cycle:        Whether starting a hibernation cycle, or just reading or
+ *                        writing a sysfs value.
+ **/
+static int toi_bio_initialise(int starting_cycle)
+{
+        int result;
+
+        if (!starting_cycle || !resume_dev_t)
+                return 0;
+
+        max_outstanding_writes = 0;
+        max_outstanding_reads = 0;
+        current_stream = 0;
+        toi_queue_flusher = current;
+#ifdef MEASURE_MUTEX_CONTENTION
+        {
+                int i, j, k;
+
+                for (i = 0; i < 2; i++)
+                        for (j = 0; j < 2; j++)
+                                for_each_online_cpu(k)
+                                        mutex_times[i][j][k] = 0;
+        }
+#endif
+        result = open_resume_dev_t(0, 1);
+
+        if (result)
+                return result;
+
+        return get_signature_page();
+}
+
+static unsigned long raw_to_real(unsigned long raw)
+{
+        unsigned long extra;
+
+        extra = (raw * (sizeof(unsigned long) + sizeof(int)) +
+                (PAGE_SIZE + sizeof(unsigned long) + sizeof(int) + 1)) /
+                (PAGE_SIZE + sizeof(unsigned long) + sizeof(int));
+
+        return raw > extra ? raw - extra : 0;
+}
+
+static unsigned long toi_bio_storage_available(void)
+{
+        unsigned long sum = 0;
+        struct toi_module_ops *this_module;
+
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                if (!this_module->enabled ||
+                    this_module->type != BIO_ALLOCATOR_MODULE)
+                        continue;
+                toi_message(TOI_BIO, TOI_VERBOSE, 0, "Seeking storage "
+                                "available from %s.", this_module->name);
+                sum += this_module->bio_allocator_ops->storage_available();
+        }
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Total storage available is %lu "
+                        "pages (%d header pages).", sum, header_pages_reserved);
+
+        return sum > header_pages_reserved ?
+                raw_to_real(sum - header_pages_reserved) : 0;
+
+}
+
+static unsigned long toi_bio_storage_allocated(void)
+{
+        return raw_pages_allocd > header_pages_reserved ?
+                raw_to_real(raw_pages_allocd - header_pages_reserved) : 0;
+}
+
+/*
+ * If we have read part of the image, we might have filled  memory with
+ * data that should be zeroed out.
+ */
+static void toi_bio_noresume_reset(void)
+{
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "toi_bio_noresume_reset.");
+        toi_rw_cleanup(READ);
+        free_all_bdev_info();
+}
+
+/**
+ * toi_bio_cleanup - cleanup after some action
+ * @finishing_cycle:        Whether completing a cycle.
+ **/
+static void toi_bio_cleanup(int finishing_cycle)
+{
+        if (!finishing_cycle)
+                return;
+
+        if (toi_writer_buffer) {
+                toi_free_page(11, (unsigned long) toi_writer_buffer);
+                toi_writer_buffer = NULL;
+        }
+
+        forget_signature_page();
+
+        if (header_block_device && toi_sig_data &&
+                        toi_sig_data->header_dev_t != resume_dev_t)
+                toi_close_bdev(header_block_device);
+
+        header_block_device = NULL;
+
+        close_resume_dev_t(0);
+}
+
+static int toi_bio_write_header_init(void)
+{
+        int result;
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "toi_bio_write_header_init");
+        toi_rw_init(WRITE, 0);
+        toi_writer_buffer_posn = 0;
+
+        /* Info needed to bootstrap goes at the start of the header.
+         * First we save the positions and devinfo, including the number
+         * of header pages. Then we save the structs containing data needed
+         * for reading the header pages back.
+         * Note that even if header pages take more than one page, when we
+         * read back the info, we will have restored the location of the
+         * next header page by the time we go to use it.
+         */
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "serialise extent chains.");
+        result = toi_serialise_extent_chains();
+
+        if (result)
+                return result;
+
+        /*
+         * Signature page hasn't been modified at this point. Write it in
+         * the header so we can restore it later.
+         */
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "serialise signature page.");
+        return toi_rw_header_chunk_noreadahead(WRITE, &toi_blockwriter_ops,
+                        (char *) toi_cur_sig_page,
+                        PAGE_SIZE);
+}
+
+static int toi_bio_write_header_cleanup(void)
+{
+        int result = 0;
+
+        if (toi_writer_buffer_posn)
+                toi_bio_queue_write(&toi_writer_buffer);
+
+        result = toi_finish_all_io();
+
+        unowned = 0;
+        total_header_bytes = 0;
+
+        /* Set signature to save we have an image */
+        if (!result)
+                result = toi_bio_mark_have_image();
+
+        return result;
+}
+
+/*
+ * toi_bio_read_header_init()
+ *
+ * Description:
+ * 1. Attempt to read the device specified with resume=.
+ * 2. Check the contents of the swap header for our signature.
+ * 3. Warn, ignore, reset and/or continue as appropriate.
+ * 4. If continuing, read the toi_swap configuration section
+ *    of the header and set up block device info so we can read
+ *    the rest of the header & image.
+ *
+ * Returns:
+ * May not return if user choose to reboot at a warning.
+ * -EINVAL if cannot resume at this time. Booting should continue
+ * normally.
+ */
+
+static int toi_bio_read_header_init(void)
+{
+        int result = 0;
+        char buf[32];
+
+        toi_writer_buffer_posn = 0;
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "toi_bio_read_header_init");
+
+        if (!toi_sig_data) {
+                printk(KERN_INFO "toi_bio_read_header_init called when we "
+                                "haven't verified there is an image!\n");
+                return -EINVAL;
+        }
+
+        /*
+         * If the header is not on the resume_swap_dev_t, get the resume device
+         * first.
+         */
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "Header dev_t is %lx.",
+                        toi_sig_data->header_dev_t);
+        if (toi_sig_data->have_uuid) {
+                struct fs_info seek;
+                dev_t device;
+
+                strncpy((char *) seek.uuid, toi_sig_data->header_uuid, 16);
+                seek.dev_t = toi_sig_data->header_dev_t;
+                seek.last_mount_size = 0;
+                device = blk_lookup_fs_info(&seek);
+                if (device) {
+                        printk("Using dev_t %s, returned by blk_lookup_fs_info.\n",
+                                        format_dev_t(buf, device));
+                        toi_sig_data->header_dev_t = device;
+                }
+        }
+        if (toi_sig_data->header_dev_t != resume_dev_t) {
+                header_block_device = toi_open_bdev(NULL,
+                                toi_sig_data->header_dev_t, 1);
+
+                if (IS_ERR(header_block_device))
+                        return PTR_ERR(header_block_device);
+        } else
+                header_block_device = resume_block_device;
+
+        if (!toi_writer_buffer)
+                toi_writer_buffer = (char *) toi_get_zeroed_page(11,
+                                TOI_ATOMIC_GFP);
+        more_readahead = 1;
+
+        /*
+         * Read toi_swap configuration.
+         * Headerblock size taken into account already.
+         */
+        result = toi_bio_ops.bdev_page_io(READ, header_block_device,
+                        toi_sig_data->first_header_block,
+                        virt_to_page((unsigned long) toi_writer_buffer));
+        if (result)
+                return result;
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "load extent chains.");
+        result = toi_load_extent_chains();
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "load original signature page.");
+        toi_orig_sig_page = (char *) toi_get_zeroed_page(38, TOI_ATOMIC_GFP);
+        if (!toi_orig_sig_page) {
+                printk(KERN_ERR "Failed to allocate memory for the current"
+                        " image signature.\n");
+                return -ENOMEM;
+        }
+
+        return toi_rw_header_chunk_noreadahead(READ, &toi_blockwriter_ops,
+                        (char *) toi_orig_sig_page,
+                        PAGE_SIZE);
+}
+
+static int toi_bio_read_header_cleanup(void)
+{
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "toi_bio_read_header_cleanup.");
+        return toi_rw_cleanup(READ);
+}
+
+/* Works only for digits and letters, but small and fast */
+#define TOLOWER(x) ((x) | 0x20)
+
+/*
+ * UUID must be 32 chars long. It may have dashes, but nothing
+ * else.
+ */
+char *uuid_from_commandline(char *commandline)
+{
+        int low = 0;
+        char *result = NULL, *output, *ptr;
+
+        if (strncmp(commandline, "UUID=", 5))
+                return NULL;
+
+        result = kzalloc(17, GFP_KERNEL);
+        if (!result) {
+                printk("Failed to kzalloc UUID text memory.\n");
+                return NULL;
+        }
+
+        ptr = commandline + 5;
+        output = result;
+
+        while (*ptr && (output - result) < 16) {
+                if (isxdigit(*ptr)) {
+                        int value = isdigit(*ptr) ? *ptr - '0' :
+                                TOLOWER(*ptr) - 'a' + 10;
+                        if (low) {
+                                *output += value;
+                                output++;
+                        } else {
+                                *output = value << 4;
+                        }
+                        low = !low;
+                } else if (*ptr != '-')
+                        break;
+                ptr++;
+        }
+
+        if ((output - result) < 16 || *ptr) {
+                printk(KERN_DEBUG "Found resume=UUID=, but the value looks "
+                                "invalid.\n");
+                kfree(result);
+                result = NULL;
+        }
+
+        return result;
+}
+
+#define retry_if_fails(command) \
+do { \
+        command; \
+        if (!resume_dev_t && !waited_for_device_probe) { \
+                wait_for_device_probe(); \
+                command; \
+                waited_for_device_probe = 1; \
+        } \
+} while(0)
+
+/**
+ * try_to_open_resume_device: Try to parse and open resume=
+ *
+ * Any "swap:" has been stripped away and we just have the path to deal with.
+ * We attempt to do name_to_dev_t, open and stat the file. Having opened the
+ * file, get the struct block_device * to match.
+ */
+static int try_to_open_resume_device(char *commandline, int quiet)
+{
+        struct kstat stat;
+        int error = 0;
+        char *uuid = uuid_from_commandline(commandline);
+        int waited_for_device_probe = 0;
+
+        resume_dev_t = MKDEV(0, 0);
+
+        if (!strlen(commandline))
+                retry_if_fails(toi_bio_scan_for_image(quiet));
+
+        if (uuid) {
+                struct fs_info seek;
+                strncpy((char *) &seek.uuid, uuid, 16);
+                seek.dev_t = resume_dev_t;
+                seek.last_mount_size = 0;
+                retry_if_fails(resume_dev_t = blk_lookup_fs_info(&seek));
+                kfree(uuid);
+        }
+
+        if (!resume_dev_t)
+                retry_if_fails(resume_dev_t = name_to_dev_t(commandline));
+
+        if (!resume_dev_t) {
+                struct file *file = filp_open(commandline,
+                                O_RDONLY|O_LARGEFILE, 0);
+
+                if (!IS_ERR(file) && file) {
+                        vfs_getattr(&file->f_path, &stat);
+                        filp_close(file, NULL);
+                } else
+                        error = vfs_stat(commandline, &stat);
+                if (!error)
+                        resume_dev_t = stat.rdev;
+        }
+
+        if (!resume_dev_t) {
+                if (quiet)
+                        return 1;
+
+                if (test_toi_state(TOI_TRYING_TO_RESUME))
+                        toi_early_boot_message(1, toi_translate_err_default,
+                          "Failed to translate \"%s\" into a device id.\n",
+                          commandline);
+                else
+                        printk("TuxOnIce: Can't translate \"%s\" into a device "
+                                        "id yet.\n", commandline);
+                return 1;
+        }
+
+        return open_resume_dev_t(1, quiet);
+}
+
+/*
+ * Parse Image Location
+ *
+ * Attempt to parse a resume= parameter.
+ * Swap Writer accepts:
+ * resume=[swap:|file:]DEVNAME[:FIRSTBLOCK][@BLOCKSIZE]
+ *
+ * Where:
+ * DEVNAME is convertable to a dev_t by name_to_dev_t
+ * FIRSTBLOCK is the location of the first block in the swap file
+ * (specifying for a swap partition is nonsensical but not prohibited).
+ * Data is validated by attempting to read a swap header from the
+ * location given. Failure will result in toi_swap refusing to
+ * save an image, and a reboot with correct parameters will be
+ * necessary.
+ */
+static int toi_bio_parse_sig_location(char *commandline,
+                int only_allocator, int quiet)
+{
+        char *thischar, *devstart, *colon = NULL;
+        int signature_found, result = -EINVAL, temp_result = 0;
+
+        if (strncmp(commandline, "swap:", 5) &&
+            strncmp(commandline, "file:", 5)) {
+                /*
+                 * Failing swap:, we'll take a simple resume=/dev/hda2, or a
+                 * blank value (scan) but fall through to other allocators
+                 * if /dev/ or UUID= isn't matched.
+                 */
+                if (strncmp(commandline, "/dev/", 5) &&
+                    strncmp(commandline, "UUID=", 5) &&
+                    strlen(commandline))
+                        return 1;
+        } else
+                commandline += 5;
+
+        devstart = commandline;
+        thischar = commandline;
+        while ((*thischar != ':') && (*thischar != '@') &&
+                ((thischar - commandline) < 250) && (*thischar))
+                thischar++;
+
+        if (*thischar == ':') {
+                colon = thischar;
+                *colon = 0;
+                thischar++;
+        }
+
+        while ((thischar - commandline) < 250 && *thischar)
+                thischar++;
+
+        if (colon) {
+                unsigned long block;
+                temp_result = kstrtoul(colon + 1, 0, &block);
+                if (!temp_result)
+                        resume_firstblock = (int) block;
+        } else
+                resume_firstblock = 0;
+
+        clear_toi_state(TOI_CAN_HIBERNATE);
+        clear_toi_state(TOI_CAN_RESUME);
+
+        if (!temp_result)
+                temp_result = try_to_open_resume_device(devstart, quiet);
+
+        if (colon)
+                *colon = ':';
+
+        /* No error if we only scanned */
+        if (temp_result)
+                return strlen(commandline) ? -EINVAL : 1;
+
+        signature_found = toi_bio_image_exists(quiet);
+
+        if (signature_found != -1) {
+                result = 0;
+                /*
+                 * TODO: If only file storage, CAN_HIBERNATE should only be
+                 * set if file allocator's target is valid.
+                 */
+                set_toi_state(TOI_CAN_HIBERNATE);
+                set_toi_state(TOI_CAN_RESUME);
+        } else
+                if (!quiet)
+                        printk(KERN_ERR "TuxOnIce: Block I/O: No "
+                                "signature found at %s.\n", devstart);
+
+        return result;
+}
+
+static void toi_bio_release_storage(void)
+{
+        header_pages_reserved = 0;
+        raw_pages_allocd = 0;
+
+        free_all_bdev_info();
+}
+
+/* toi_swap_remove_image
+ *
+ */
+static int toi_bio_remove_image(void)
+{
+        int result;
+
+        toi_message(TOI_BIO, TOI_VERBOSE, 0, "toi_bio_remove_image.");
+
+        result = toi_bio_restore_original_signature();
+
+        /*
+         * We don't do a sanity check here: we want to restore the swap
+         * whatever version of kernel made the hibernate image.
+         *
+         * We need to write swap, but swap may not be enabled so
+         * we write the device directly
+         *
+         * If we don't have an current_signature_page, we didn't
+         * read an image header, so don't change anything.
+         */
+
+        toi_bio_release_storage();
+
+        return result;
+}
+
+struct toi_bio_ops toi_bio_ops = {
+        .bdev_page_io = toi_bdev_page_io,
+        .register_storage = toi_register_storage_chain,
+        .free_storage = toi_bio_release_storage,
+};
+
+static struct toi_sysfs_data sysfs_params[] = {
+        SYSFS_INT("target_outstanding_io", SYSFS_RW, &target_outstanding_io,
+                        0, 16384, 0, NULL),
+};
+
+struct toi_module_ops toi_blockwriter_ops = {
+        .type                                = WRITER_MODULE,
+        .name                                = "block i/o",
+        .directory                        = "block_io",
+        .module                                = THIS_MODULE,
+        .memory_needed                        = toi_bio_memory_needed,
+        .print_debug_info                = toi_bio_print_debug_stats,
+        .storage_needed                        = toi_bio_storage_needed,
+        .save_config_info                = toi_bio_save_config_info,
+        .load_config_info                = toi_bio_load_config_info,
+        .initialise                        = toi_bio_initialise,
+        .cleanup                        = toi_bio_cleanup,
+        .post_atomic_restore                = toi_bio_chains_post_atomic,
+
+        .rw_init                        = toi_rw_init,
+        .rw_cleanup                        = toi_rw_cleanup,
+        .read_page                        = toi_bio_read_page,
+        .write_page                        = toi_bio_write_page,
+        .rw_header_chunk                = toi_rw_header_chunk,
+        .rw_header_chunk_noreadahead        = toi_rw_header_chunk_noreadahead,
+        .io_flusher                        = bio_io_flusher,
+        .update_throughput_throttle        = update_throughput_throttle,
+        .finish_all_io                        = toi_finish_all_io,
+
+        .noresume_reset                        = toi_bio_noresume_reset,
+        .storage_available                 = toi_bio_storage_available,
+        .storage_allocated                = toi_bio_storage_allocated,
+        .reserve_header_space                = toi_bio_reserve_header_space,
+        .allocate_storage                = toi_bio_allocate_storage,
+        .free_unused_storage            = toi_bio_free_unused_storage,
+        .image_exists                        = toi_bio_image_exists,
+        .mark_resume_attempted                = toi_bio_mark_resume_attempted,
+        .write_header_init                = toi_bio_write_header_init,
+        .write_header_cleanup                = toi_bio_write_header_cleanup,
+        .read_header_init                = toi_bio_read_header_init,
+        .read_header_cleanup                = toi_bio_read_header_cleanup,
+        .get_header_version                = toi_bio_get_header_version,
+        .remove_image                        = toi_bio_remove_image,
+        .parse_sig_location                = toi_bio_parse_sig_location,
+
+        .sysfs_data                        = sysfs_params,
+        .num_sysfs_entries                = sizeof(sysfs_params) /
+                sizeof(struct toi_sysfs_data),
+};
+
+/**
+ * toi_block_io_load - load time routine for block I/O module
+ *
+ * Register block i/o ops and sysfs entries.
+ **/
+static __init int toi_block_io_load(void)
+{
+        return toi_register_module(&toi_blockwriter_ops);
+}
+
+late_initcall(toi_block_io_load);
diff --git a/kernel/power/tuxonice_bio_internal.h b/kernel/power/tuxonice_bio_internal.h
new file mode 100644
index 000000000..5e1964a61
--- /dev/null
+++ b/kernel/power/tuxonice_bio_internal.h
@@ -0,0 +1,101 @@
+/*
+ * kernel/power/tuxonice_bio_internal.h
+ *
+ * Copyright (C) 2009-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * Distributed under GPLv2.
+ *
+ * This file contains declarations for functions exported from
+ * tuxonice_bio.c, which contains low level io functions.
+ */
+
+/* Extent chains */
+void toi_extent_state_goto_start(void);
+void toi_extent_state_save(int slot);
+int go_next_page(int writing, int section_barrier);
+void toi_extent_state_restore(int slot);
+void free_all_bdev_info(void);
+int devices_of_same_priority(struct toi_bdev_info *this);
+int toi_register_storage_chain(struct toi_bdev_info *new);
+int toi_serialise_extent_chains(void);
+int toi_load_extent_chains(void);
+int toi_bio_rw_page(int writing, struct page *page, int is_readahead,
+                int free_group);
+int toi_bio_restore_original_signature(void);
+int toi_bio_devinfo_storage_needed(void);
+unsigned long get_headerblock(void);
+dev_t get_header_dev_t(void);
+struct block_device *get_header_bdev(void);
+int toi_bio_allocate_storage(unsigned long request);
+void toi_bio_free_unused_storage(void);
+
+/* Signature functions */
+#define HaveImage "HaveImage"
+#define NoImage "TuxOnIce"
+#define sig_size (sizeof(HaveImage))
+
+struct sig_data {
+        char sig[sig_size];
+        int have_image;
+        int resumed_before;
+
+        char have_uuid;
+        char header_uuid[17];
+        dev_t header_dev_t;
+        unsigned long first_header_block;
+
+        /* Repeat the signature to be sure we have a header version */
+        char sig2[sig_size];
+        int header_version;
+};
+
+void forget_signature_page(void);
+int toi_check_for_signature(void);
+int toi_bio_image_exists(int quiet);
+int get_signature_page(void);
+int toi_bio_mark_resume_attempted(int);
+extern char *toi_cur_sig_page;
+extern char *toi_orig_sig_page;
+int toi_bio_mark_have_image(void);
+extern struct sig_data *toi_sig_data;
+extern dev_t resume_dev_t;
+extern struct block_device *resume_block_device;
+extern struct block_device *header_block_device;
+extern unsigned long resume_firstblock;
+
+struct block_device *open_bdev(dev_t device, int display_errs);
+extern int current_stream;
+extern int more_readahead;
+int toi_do_io(int writing, struct block_device *bdev, long block0,
+        struct page *page, int is_readahead, int syncio, int free_group);
+int get_main_pool_phys_params(void);
+
+void toi_close_bdev(struct block_device *bdev);
+struct block_device *toi_open_bdev(char *uuid, dev_t default_device,
+                int display_errs);
+
+extern struct toi_module_ops toi_blockwriter_ops;
+void dump_block_chains(void);
+void debug_broken_header(void);
+extern unsigned long raw_pages_allocd, header_pages_reserved;
+int toi_bio_chains_debug_info(char *buffer, int size);
+void toi_bio_chains_post_atomic(struct toi_boot_kernel_data *bkd);
+int toi_bio_scan_for_image(int quiet);
+int toi_bio_get_header_version(void);
+
+void close_resume_dev_t(int force);
+int open_resume_dev_t(int force, int quiet);
+
+struct toi_incremental_image_pointer_saved_data {
+    unsigned long block;
+    int chain;
+};
+
+struct toi_incremental_image_pointer {
+    struct toi_incremental_image_pointer_saved_data save;
+    struct block_device *bdev;
+    unsigned long block;
+};
+
+void toi_bio_store_inc_image_ptr(struct toi_incremental_image_pointer *ptr);
+void toi_bio_restore_inc_image_ptr(struct toi_incremental_image_pointer *ptr);
diff --git a/kernel/power/tuxonice_bio_signature.c b/kernel/power/tuxonice_bio_signature.c
new file mode 100644
index 000000000..f5418f092
--- /dev/null
+++ b/kernel/power/tuxonice_bio_signature.c
@@ -0,0 +1,403 @@
+/*
+ * kernel/power/tuxonice_bio_signature.c
+ *
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * Distributed under GPLv2.
+ *
+ */
+
+#include <linux/fs_uuid.h>
+
+#include "tuxonice.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_prepare_image.h"
+#include "tuxonice_bio.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_alloc.h"
+#include "tuxonice_io.h"
+#include "tuxonice_builtin.h"
+#include "tuxonice_bio_internal.h"
+
+struct sig_data *toi_sig_data;
+
+/* Struct of swap header pages */
+
+struct old_sig_data {
+        dev_t device;
+        unsigned long sector;
+        int resume_attempted;
+        int orig_sig_type;
+};
+
+union diskpage {
+        union swap_header swh;        /* swh.magic is the only member used */
+        struct sig_data sig_data;
+        struct old_sig_data old_sig_data;
+};
+
+union p_diskpage {
+        union diskpage *pointer;
+        char *ptr;
+        unsigned long address;
+};
+
+char *toi_cur_sig_page;
+char *toi_orig_sig_page;
+int have_image;
+int have_old_image;
+
+int get_signature_page(void)
+{
+        if (!toi_cur_sig_page) {
+                toi_message(TOI_IO, TOI_VERBOSE, 0,
+                                "Allocating current signature page.");
+                toi_cur_sig_page = (char *) toi_get_zeroed_page(38,
+                        TOI_ATOMIC_GFP);
+                if (!toi_cur_sig_page) {
+                        printk(KERN_ERR "Failed to allocate memory for the "
+                                "current image signature.\n");
+                        return -ENOMEM;
+                }
+
+                toi_sig_data = (struct sig_data *) toi_cur_sig_page;
+        }
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "Reading signature from dev %lx,"
+                        " sector %d.",
+                        resume_block_device->bd_dev, resume_firstblock);
+
+        return toi_bio_ops.bdev_page_io(READ, resume_block_device,
+                resume_firstblock, virt_to_page(toi_cur_sig_page));
+}
+
+void forget_signature_page(void)
+{
+        if (toi_cur_sig_page) {
+                toi_sig_data = NULL;
+                toi_message(TOI_IO, TOI_VERBOSE, 0, "Freeing toi_cur_sig_page"
+                                " (%p).", toi_cur_sig_page);
+                toi_free_page(38, (unsigned long) toi_cur_sig_page);
+                toi_cur_sig_page = NULL;
+        }
+
+        if (toi_orig_sig_page) {
+                toi_message(TOI_IO, TOI_VERBOSE, 0, "Freeing toi_orig_sig_page"
+                                " (%p).", toi_orig_sig_page);
+                toi_free_page(38, (unsigned long) toi_orig_sig_page);
+                toi_orig_sig_page = NULL;
+        }
+}
+
+/*
+ * We need to ensure we use the signature page that's currently on disk,
+ * so as to not remove the image header. Post-atomic-restore, the orig sig
+ * page will be empty, so we can use that as our method of knowing that we
+ * need to load the on-disk signature and not use the non-image sig in
+ * memory. (We're going to powerdown after writing the change, so it's safe.
+ */
+int toi_bio_mark_resume_attempted(int flag)
+{
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "Make resume attempted = %d.",
+                        flag);
+        if (!toi_orig_sig_page) {
+                forget_signature_page();
+                get_signature_page();
+        }
+        toi_sig_data->resumed_before = flag;
+        return toi_bio_ops.bdev_page_io(WRITE, resume_block_device,
+                resume_firstblock, virt_to_page(toi_cur_sig_page));
+}
+
+int toi_bio_mark_have_image(void)
+{
+        int result = 0;
+        char buf[32];
+        struct fs_info *fs_info;
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "Recording that an image exists.");
+        memcpy(toi_sig_data->sig, tuxonice_signature,
+                        sizeof(tuxonice_signature));
+        toi_sig_data->have_image = 1;
+        toi_sig_data->resumed_before = 0;
+        toi_sig_data->header_dev_t = get_header_dev_t();
+        toi_sig_data->have_uuid = 0;
+
+        fs_info = fs_info_from_block_dev(get_header_bdev());
+        if (fs_info && !IS_ERR(fs_info)) {
+                memcpy(toi_sig_data->header_uuid, &fs_info->uuid, 16);
+                free_fs_info(fs_info);
+        } else
+                result = (int) PTR_ERR(fs_info);
+
+        if (!result) {
+                toi_message(TOI_IO, TOI_VERBOSE, 0, "Got uuid for dev_t %s.",
+                                format_dev_t(buf, get_header_dev_t()));
+                toi_sig_data->have_uuid = 1;
+        } else
+                toi_message(TOI_IO, TOI_VERBOSE, 0, "Could not get uuid for "
+                                "dev_t %s.",
+                                format_dev_t(buf, get_header_dev_t()));
+
+        toi_sig_data->first_header_block = get_headerblock();
+        have_image = 1;
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "header dev_t is %x. First block "
+                        "is %d.", toi_sig_data->header_dev_t,
+                        toi_sig_data->first_header_block);
+
+        memcpy(toi_sig_data->sig2, tuxonice_signature,
+                        sizeof(tuxonice_signature));
+        toi_sig_data->header_version = TOI_HEADER_VERSION;
+
+        return toi_bio_ops.bdev_page_io(WRITE, resume_block_device,
+                resume_firstblock, virt_to_page(toi_cur_sig_page));
+}
+
+int remove_old_signature(void)
+{
+        union p_diskpage swap_header_page = (union p_diskpage) toi_cur_sig_page;
+        char *orig_sig;
+        char *header_start = (char *) toi_get_zeroed_page(38, TOI_ATOMIC_GFP);
+        int result;
+        struct block_device *header_bdev;
+        struct old_sig_data *old_sig_data =
+                &swap_header_page.pointer->old_sig_data;
+
+        header_bdev = toi_open_bdev(NULL, old_sig_data->device, 1);
+        result = toi_bio_ops.bdev_page_io(READ, header_bdev,
+                        old_sig_data->sector, virt_to_page(header_start));
+
+        if (result)
+                goto out;
+
+        /*
+         * TODO: Get the original contents of the first bytes of the swap
+         * header page.
+         */
+        if (!old_sig_data->orig_sig_type)
+                orig_sig = "SWAP-SPACE";
+        else
+                orig_sig = "SWAPSPACE2";
+
+        memcpy(swap_header_page.pointer->swh.magic.magic, orig_sig, 10);
+        memcpy(swap_header_page.ptr, header_start, 10);
+
+        result = toi_bio_ops.bdev_page_io(WRITE, resume_block_device,
+                resume_firstblock, virt_to_page(swap_header_page.ptr));
+
+out:
+        toi_close_bdev(header_bdev);
+        have_old_image = 0;
+        toi_free_page(38, (unsigned long) header_start);
+        return result;
+}
+
+/*
+ * toi_bio_restore_original_signature - restore the original signature
+ *
+ * At boot time (aborting pre atomic-restore), toi_orig_sig_page gets used.
+ * It will have the original signature page contents, stored in the image
+ * header. Post atomic-restore, we use :toi_cur_sig_page, which will contain
+ * the contents that were loaded when we started the cycle.
+ */
+int toi_bio_restore_original_signature(void)
+{
+        char *use = toi_orig_sig_page ? toi_orig_sig_page : toi_cur_sig_page;
+
+        if (have_old_image)
+                return remove_old_signature();
+
+        if (!use) {
+                printk("toi_bio_restore_original_signature: No signature "
+                                "page loaded.\n");
+                return 0;
+        }
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "Recording that no image exists.");
+        have_image = 0;
+        toi_sig_data->have_image = 0;
+        return toi_bio_ops.bdev_page_io(WRITE, resume_block_device,
+                resume_firstblock, virt_to_page(use));
+}
+
+/*
+ * check_for_signature - See whether we have an image.
+ *
+ * Returns 0 if no image, 1 if there is one, -1 if indeterminate.
+ */
+int toi_check_for_signature(void)
+{
+        union p_diskpage swap_header_page;
+        int type;
+        const char *normal_sigs[] = {"SWAP-SPACE", "SWAPSPACE2" };
+        const char *swsusp_sigs[] = {"S1SUSP", "S2SUSP", "S1SUSPEND" };
+        char *swap_header;
+
+        if (!toi_cur_sig_page) {
+                int result = get_signature_page();
+
+                if (result)
+                        return result;
+        }
+
+        /*
+         * Start by looking for the binary header.
+         */
+        if (!memcmp(tuxonice_signature, toi_cur_sig_page,
+                                sizeof(tuxonice_signature))) {
+                have_image = toi_sig_data->have_image;
+                toi_message(TOI_IO, TOI_VERBOSE, 0, "Have binary signature. "
+                                "Have image is %d.", have_image);
+                if (have_image)
+                        toi_message(TOI_IO, TOI_VERBOSE, 0, "header dev_t is "
+                                        "%x. First block is %d.",
+                                        toi_sig_data->header_dev_t,
+                                        toi_sig_data->first_header_block);
+                return toi_sig_data->have_image;
+        }
+
+        /*
+         * Failing that, try old file allocator headers.
+         */
+
+        if (!memcmp(HaveImage, toi_cur_sig_page, strlen(HaveImage))) {
+                have_image = 1;
+                return 1;
+        }
+
+        have_image = 0;
+
+        if (!memcmp(NoImage, toi_cur_sig_page, strlen(NoImage)))
+                return 0;
+
+        /*
+         * Nope? How about swap?
+         */
+        swap_header_page = (union p_diskpage) toi_cur_sig_page;
+        swap_header = swap_header_page.pointer->swh.magic.magic;
+
+        /* Normal swapspace? */
+        for (type = 0; type < 2; type++)
+                if (!memcmp(normal_sigs[type], swap_header,
+                                        strlen(normal_sigs[type])))
+                        return 0;
+
+        /* Swsusp or uswsusp? */
+        for (type = 0; type < 3; type++)
+                if (!memcmp(swsusp_sigs[type], swap_header,
+                                        strlen(swsusp_sigs[type])))
+                        return 2;
+
+        /* Old TuxOnIce version? */
+        if (!memcmp(tuxonice_signature, swap_header,
+                                sizeof(tuxonice_signature) - 1)) {
+                toi_message(TOI_IO, TOI_VERBOSE, 0, "Found old TuxOnIce "
+                                "signature.");
+                have_old_image = 1;
+                return 3;
+        }
+
+        return -1;
+}
+
+/*
+ * Image_exists
+ *
+ * Returns -1 if don't know, otherwise 0 (no) or 1 (yes).
+ */
+int toi_bio_image_exists(int quiet)
+{
+        int result;
+        char *msg = NULL;
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "toi_bio_image_exists.");
+
+        if (!resume_dev_t) {
+                if (!quiet)
+                        printk(KERN_INFO "Not even trying to read header "
+                                "because resume_dev_t is not set.\n");
+                return -1;
+        }
+
+        if (open_resume_dev_t(0, quiet))
+                return -1;
+
+        result = toi_check_for_signature();
+
+        clear_toi_state(TOI_RESUMED_BEFORE);
+        if (toi_sig_data->resumed_before)
+                set_toi_state(TOI_RESUMED_BEFORE);
+
+        if (quiet || result == -ENOMEM)
+                return result;
+
+        if (result == -1)
+                msg = "TuxOnIce: Unable to find a signature."
+                                " Could you have moved a swap file?\n";
+        else if (!result)
+                msg = "TuxOnIce: No image found.\n";
+        else if (result == 1)
+                msg = "TuxOnIce: Image found.\n";
+        else if (result == 2)
+                msg = "TuxOnIce: uswsusp or swsusp image found.\n";
+        else if (result == 3)
+                msg = "TuxOnIce: Old implementation's signature found.\n";
+
+        printk(KERN_INFO "%s", msg);
+
+        return result;
+}
+
+int toi_bio_scan_for_image(int quiet)
+{
+        struct block_device *bdev;
+        char default_name[255] = "";
+
+        if (!quiet)
+                printk(KERN_DEBUG "Scanning swap devices for TuxOnIce "
+                                "signature...\n");
+        for (bdev = next_bdev_of_type(NULL, "swap"); bdev;
+                                bdev = next_bdev_of_type(bdev, "swap")) {
+                int result;
+                char name[255] = "";
+                sprintf(name, "%u:%u", MAJOR(bdev->bd_dev),
+                                MINOR(bdev->bd_dev));
+                if (!quiet)
+                        printk(KERN_DEBUG "- Trying %s.\n", name);
+                resume_block_device = bdev;
+                resume_dev_t = bdev->bd_dev;
+
+                result = toi_check_for_signature();
+
+                resume_block_device = NULL;
+                resume_dev_t = MKDEV(0, 0);
+
+                if (!default_name[0])
+                        strcpy(default_name, name);
+
+                if (result == 1) {
+                        /* Got one! */
+                        strcpy(resume_file, name);
+                        next_bdev_of_type(bdev, NULL);
+                        if (!quiet)
+                                printk(KERN_DEBUG " ==> Image found on %s.\n",
+                                                resume_file);
+                        return 1;
+                }
+                forget_signature_page();
+        }
+
+        if (!quiet)
+                printk(KERN_DEBUG "TuxOnIce scan: No image found.\n");
+        strcpy(resume_file, default_name);
+        return 0;
+}
+
+int toi_bio_get_header_version(void)
+{
+        return (memcmp(toi_sig_data->sig2, tuxonice_signature,
+                                sizeof(tuxonice_signature))) ?
+                0 : toi_sig_data->header_version;
+
+}
diff --git a/kernel/power/tuxonice_builtin.c b/kernel/power/tuxonice_builtin.c
new file mode 100644
index 000000000..22bf07a43
--- /dev/null
+++ b/kernel/power/tuxonice_builtin.c
@@ -0,0 +1,498 @@
+/*
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ */
+#include <linux/kernel.h>
+#include <linux/swap.h>
+#include <linux/syscalls.h>
+#include <linux/bio.h>
+#include <linux/root_dev.h>
+#include <linux/freezer.h>
+#include <linux/reboot.h>
+#include <linux/writeback.h>
+#include <linux/tty.h>
+#include <linux/crypto.h>
+#include <linux/cpu.h>
+#include <linux/ctype.h>
+#include <linux/kthread.h>
+#include "tuxonice_io.h"
+#include "tuxonice.h"
+#include "tuxonice_extent.h"
+#include "tuxonice_netlink.h"
+#include "tuxonice_prepare_image.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice_pagedir.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_builtin.h"
+#include "tuxonice_power_off.h"
+#include "tuxonice_alloc.h"
+
+unsigned long toi_bootflags_mask;
+
+/*
+ * Highmem related functions (x86 only).
+ */
+
+#ifdef CONFIG_HIGHMEM
+
+/**
+ * copyback_high: Restore highmem pages.
+ *
+ * Highmem data and pbe lists are/can be stored in highmem.
+ * The format is slightly different to the lowmem pbe lists
+ * used for the assembly code: the last pbe in each page is
+ * a struct page * instead of struct pbe *, pointing to the
+ * next page where pbes are stored (or NULL if happens to be
+ * the end of the list). Since we don't want to generate
+ * unnecessary deltas against swsusp code, we use a cast
+ * instead of a union.
+ **/
+
+static void copyback_high(void)
+{
+        struct page *pbe_page = (struct page *) restore_highmem_pblist;
+        struct pbe *this_pbe, *first_pbe;
+        unsigned long *origpage, *copypage;
+        int pbe_index = 1;
+
+        if (!pbe_page)
+                return;
+
+        this_pbe = (struct pbe *) kmap_atomic(pbe_page);
+        first_pbe = this_pbe;
+
+        while (this_pbe) {
+                int loop = (PAGE_SIZE / sizeof(unsigned long)) - 1;
+
+                origpage = kmap_atomic(pfn_to_page((unsigned long) this_pbe->orig_address));
+                copypage = kmap_atomic((struct page *) this_pbe->address);
+
+                while (loop >= 0) {
+                        *(origpage + loop) = *(copypage + loop);
+                        loop--;
+                }
+
+                kunmap_atomic(origpage);
+                kunmap_atomic(copypage);
+
+                if (!this_pbe->next)
+                        break;
+
+                if (pbe_index < PBES_PER_PAGE) {
+                        this_pbe++;
+                        pbe_index++;
+                } else {
+                        pbe_page = (struct page *) this_pbe->next;
+                        kunmap_atomic(first_pbe);
+                        if (!pbe_page)
+                                return;
+                        this_pbe = (struct pbe *) kmap_atomic(pbe_page);
+                        first_pbe = this_pbe;
+                        pbe_index = 1;
+                }
+        }
+        kunmap_atomic(first_pbe);
+}
+
+#else /* CONFIG_HIGHMEM */
+static void copyback_high(void) { }
+#endif
+
+char toi_wait_for_keypress_dev_console(int timeout)
+{
+        int fd, this_timeout = 255, orig_kthread = 0;
+        char key = '\0';
+        struct termios t, t_backup;
+
+        /* We should be guaranteed /dev/console exists after populate_rootfs()
+         * in init/main.c.
+         */
+        fd = sys_open("/dev/console", O_RDONLY, 0);
+        if (fd < 0) {
+                printk(KERN_INFO "Couldn't open /dev/console.\n");
+                return key;
+        }
+
+        if (sys_ioctl(fd, TCGETS, (long)&t) < 0)
+                goto out_close;
+
+        memcpy(&t_backup, &t, sizeof(t));
+
+        t.c_lflag &= ~(ISIG|ICANON|ECHO);
+        t.c_cc[VMIN] = 0;
+
+new_timeout:
+        if (timeout > 0) {
+                this_timeout = timeout < 26 ? timeout : 25;
+                timeout -= this_timeout;
+                this_timeout *= 10;
+        }
+
+        t.c_cc[VTIME] = this_timeout;
+
+        if (sys_ioctl(fd, TCSETS, (long)&t) < 0)
+                goto out_restore;
+
+        if (current->flags & PF_KTHREAD) {
+            orig_kthread = (current->flags & PF_KTHREAD);
+            current->flags &= ~PF_KTHREAD;
+        }
+
+        while (1) {
+                if (sys_read(fd, &key, 1) <= 0) {
+                        if (timeout)
+                                goto new_timeout;
+                        key = '\0';
+                        break;
+                }
+                key = tolower(key);
+                if (test_toi_state(TOI_SANITY_CHECK_PROMPT)) {
+                        if (key == 'c') {
+                                set_toi_state(TOI_CONTINUE_REQ);
+                                break;
+                        } else if (key == ' ')
+                                break;
+                } else
+                        break;
+        }
+        if (orig_kthread) {
+            current->flags |= PF_KTHREAD;
+        }
+
+out_restore:
+        sys_ioctl(fd, TCSETS, (long)&t_backup);
+out_close:
+        sys_close(fd);
+
+        return key;
+}
+
+struct toi_boot_kernel_data toi_bkd __nosavedata
+                __attribute__((aligned(PAGE_SIZE))) = {
+        MY_BOOT_KERNEL_DATA_VERSION,
+        0,
+#ifdef CONFIG_TOI_REPLACE_SWSUSP
+        (1 << TOI_REPLACE_SWSUSP) |
+#endif
+        (1 << TOI_NO_FLUSHER_THREAD) |
+        (1 << TOI_PAGESET2_FULL),
+};
+
+struct block_device *toi_open_by_devnum(dev_t dev)
+{
+        struct block_device *bdev = bdget(dev);
+        int err = -ENOMEM;
+        if (bdev)
+                err = blkdev_get(bdev, FMODE_READ | FMODE_NDELAY, NULL);
+        return err ? ERR_PTR(err) : bdev;
+}
+
+/**
+ * toi_close_bdev: Close a swap bdev.
+ *
+ * int: The swap entry number to close.
+ */
+void toi_close_bdev(struct block_device *bdev)
+{
+        blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
+}
+
+int toi_wait = CONFIG_TOI_DEFAULT_WAIT;
+struct toi_core_fns *toi_core_fns;
+unsigned long toi_result;
+struct pagedir pagedir1 = {1};
+struct toi_cbw **toi_first_cbw;
+int toi_next_cbw;
+
+unsigned long toi_get_nonconflicting_page(void)
+{
+        return toi_core_fns->get_nonconflicting_page();
+}
+
+int toi_post_context_save(void)
+{
+        return toi_core_fns->post_context_save();
+}
+
+int try_tuxonice_hibernate(void)
+{
+        if (!toi_core_fns)
+                return -ENODEV;
+
+        return toi_core_fns->try_hibernate();
+}
+
+static int num_resume_calls;
+#ifdef CONFIG_TOI_IGNORE_LATE_INITCALL
+static int ignore_late_initcall = 1;
+#else
+static int ignore_late_initcall;
+#endif
+
+int toi_translate_err_default = TOI_CONTINUE_REQ;
+
+void try_tuxonice_resume(void)
+{
+        if (!hibernation_available())
+                return;
+
+        /* Don't let it wrap around eventually */
+        if (num_resume_calls < 2)
+                num_resume_calls++;
+
+        if (num_resume_calls == 1 && ignore_late_initcall) {
+                printk(KERN_INFO "TuxOnIce: Ignoring late initcall, as requested.\n");
+                return;
+        }
+
+        if (toi_core_fns)
+                toi_core_fns->try_resume();
+        else
+                printk(KERN_INFO "TuxOnIce core not loaded yet.\n");
+}
+
+int toi_lowlevel_builtin(void)
+{
+        int error = 0;
+
+        save_processor_state();
+        error = swsusp_arch_suspend();
+        if (error)
+                printk(KERN_ERR "Error %d hibernating\n", error);
+
+        /* Restore control flow appears here */
+        if (!toi_in_hibernate) {
+                copyback_high();
+                set_toi_state(TOI_NOW_RESUMING);
+        }
+
+        restore_processor_state();
+        return error;
+}
+
+unsigned long toi_compress_bytes_in;
+unsigned long toi_compress_bytes_out;
+
+int toi_in_suspend(void)
+{
+  return in_suspend;
+}
+
+unsigned long toi_state = ((1 << TOI_BOOT_TIME) |
+                (1 << TOI_IGNORE_LOGLEVEL) |
+                (1 << TOI_IO_STOPPED));
+
+/* The number of hibernates we have started (some may have been cancelled) */
+unsigned int nr_hibernates;
+int toi_running;
+__nosavedata int toi_in_hibernate;
+__nosavedata struct pbe *restore_highmem_pblist;
+
+int toi_trace_allocs;
+
+void toi_read_lock_tasklist(void)
+{
+        read_lock(&tasklist_lock);
+}
+
+void toi_read_unlock_tasklist(void)
+{
+        read_unlock(&tasklist_lock);
+}
+
+#ifdef CONFIG_TOI_ZRAM_SUPPORT
+int (*toi_flag_zram_disks) (void);
+
+int toi_do_flag_zram_disks(void)
+{
+        return toi_flag_zram_disks ? (*toi_flag_zram_disks)() : 0;
+}
+
+#endif
+
+/* toi_generate_free_page_map
+ *
+ * Description:        This routine generates a bitmap of free pages from the
+ *                 lists used by the memory manager. We then use the bitmap
+ *                 to quickly calculate which pages to save and in which
+ *                 pagesets.
+ */
+void toi_generate_free_page_map(void)
+{
+        int order, cpu, t;
+        unsigned long flags, i;
+        struct zone *zone;
+        struct list_head *curr;
+        unsigned long pfn;
+        struct page *page;
+
+        for_each_populated_zone(zone) {
+
+                if (!zone->spanned_pages)
+                        continue;
+
+                spin_lock_irqsave(&zone->lock, flags);
+
+                for (i = 0; i < zone->spanned_pages; i++) {
+                        pfn = zone->zone_start_pfn + i;
+
+                        if (!pfn_valid(pfn))
+                                continue;
+
+                        page = pfn_to_page(pfn);
+
+                        ClearPageNosaveFree(page);
+                }
+
+                for_each_migratetype_order(order, t) {
+                        list_for_each(curr,
+                                        &zone->free_area[order].free_list[t]) {
+                                unsigned long j;
+
+                                pfn = page_to_pfn(list_entry(curr, struct page,
+                                                        lru));
+                                for (j = 0; j < (1UL << order); j++)
+                                        SetPageNosaveFree(pfn_to_page(pfn + j));
+                        }
+                }
+
+                for_each_online_cpu(cpu) {
+                        struct per_cpu_pageset *pset =
+                                per_cpu_ptr(zone->pageset, cpu);
+                        struct per_cpu_pages *pcp = &pset->pcp;
+                        struct page *page;
+                        int t;
+
+                        for (t = 0; t < MIGRATE_PCPTYPES; t++)
+                                list_for_each_entry(page, &pcp->lists[t], lru)
+                                        SetPageNosaveFree(page);
+                }
+
+                spin_unlock_irqrestore(&zone->lock, flags);
+        }
+}
+
+/* toi_size_of_free_region
+ *
+ * Description:        Return the number of pages that are free, beginning with and
+ *                 including this one.
+ */
+int toi_size_of_free_region(struct zone *zone, unsigned long start_pfn)
+{
+        unsigned long this_pfn = start_pfn,
+                      end_pfn = zone_end_pfn(zone);
+
+        while (pfn_valid(this_pfn) && this_pfn < end_pfn && PageNosaveFree(pfn_to_page(this_pfn)))
+                this_pfn++;
+
+        return this_pfn - start_pfn;
+}
+
+static int __init toi_wait_setup(char *str)
+{
+        int value;
+
+        if (sscanf(str, "=%d", &value)) {
+                if (value < -1 || value > 255)
+                        printk(KERN_INFO "TuxOnIce_wait outside range -1 to "
+                                        "255.\n");
+                else
+                        toi_wait = value;
+        }
+
+        return 1;
+}
+__setup("toi_wait", toi_wait_setup);
+
+static int __init toi_translate_retry_setup(char *str)
+{
+        toi_translate_err_default = 0;
+        return 1;
+}
+__setup("toi_translate_retry", toi_translate_retry_setup);
+
+static int __init toi_debug_setup(char *str)
+{
+        toi_bkd.toi_action |= (1 << TOI_LOGALL);
+        toi_bootflags_mask |= (1 << TOI_LOGALL);
+        toi_bkd.toi_debug_state = 255;
+        toi_bkd.toi_default_console_level = 7;
+        return 1;
+}
+__setup("toi_debug_setup", toi_debug_setup);
+
+static int __init toi_pause_setup(char *str)
+{
+        toi_bkd.toi_action |= (1 << TOI_PAUSE);
+        toi_bootflags_mask |= (1 << TOI_PAUSE);
+        return 1;
+}
+__setup("toi_pause", toi_pause_setup);
+
+#ifdef CONFIG_PM_DEBUG
+static int __init toi_trace_allocs_setup(char *str)
+{
+        int value;
+
+        if (sscanf(str, "=%d", &value))
+                toi_trace_allocs = value;
+
+        return 1;
+}
+__setup("toi_trace_allocs", toi_trace_allocs_setup);
+#endif
+
+static int __init toi_ignore_late_initcall_setup(char *str)
+{
+        int value;
+
+        if (sscanf(str, "=%d", &value))
+                ignore_late_initcall = value;
+
+        return 1;
+}
+__setup("toi_initramfs_resume_only", toi_ignore_late_initcall_setup);
+
+static int __init toi_force_no_multithreaded_setup(char *str)
+{
+        int value;
+
+        toi_bkd.toi_action &= ~(1 << TOI_NO_MULTITHREADED_IO);
+        toi_bootflags_mask |= (1 << TOI_NO_MULTITHREADED_IO);
+
+        if (sscanf(str, "=%d", &value) && value)
+                toi_bkd.toi_action |= (1 << TOI_NO_MULTITHREADED_IO);
+
+        return 1;
+}
+__setup("toi_no_multithreaded", toi_force_no_multithreaded_setup);
+
+#ifdef CONFIG_KGDB
+static int __init toi_post_resume_breakpoint_setup(char *str)
+{
+        int value;
+
+        toi_bkd.toi_action &= ~(1 << TOI_POST_RESUME_BREAKPOINT);
+        toi_bootflags_mask |= (1 << TOI_POST_RESUME_BREAKPOINT);
+        if (sscanf(str, "=%d", &value) && value)
+                toi_bkd.toi_action |= (1 << TOI_POST_RESUME_BREAKPOINT);
+
+        return 1;
+}
+__setup("toi_post_resume_break", toi_post_resume_breakpoint_setup);
+#endif
+
+static int __init toi_disable_readahead_setup(char *str)
+{
+        int value;
+
+        toi_bkd.toi_action &= ~(1 << TOI_NO_READAHEAD);
+        toi_bootflags_mask |= (1 << TOI_NO_READAHEAD);
+        if (sscanf(str, "=%d", &value) && value)
+                toi_bkd.toi_action |= (1 << TOI_NO_READAHEAD);
+
+        return 1;
+}
+__setup("toi_no_readahead", toi_disable_readahead_setup);
diff --git a/kernel/power/tuxonice_builtin.h b/kernel/power/tuxonice_builtin.h
new file mode 100644
index 000000000..9539818e0
--- /dev/null
+++ b/kernel/power/tuxonice_builtin.h
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ */
+#include <asm/setup.h>
+
+extern struct toi_core_fns *toi_core_fns;
+extern unsigned long toi_compress_bytes_in, toi_compress_bytes_out;
+extern unsigned int nr_hibernates;
+extern int toi_in_hibernate;
+
+extern __nosavedata struct pbe *restore_highmem_pblist;
+
+int toi_lowlevel_builtin(void);
+
+#ifdef CONFIG_HIGHMEM
+extern __nosavedata struct zone_data *toi_nosave_zone_list;
+extern __nosavedata unsigned long toi_nosave_max_pfn;
+#endif
+
+extern unsigned long toi_get_nonconflicting_page(void);
+extern int toi_post_context_save(void);
+
+extern char toi_wait_for_keypress_dev_console(int timeout);
+extern struct block_device *toi_open_by_devnum(dev_t dev);
+extern void toi_close_bdev(struct block_device *bdev);
+extern int toi_wait;
+extern int toi_translate_err_default;
+extern int toi_force_no_multithreaded;
+extern void toi_read_lock_tasklist(void);
+extern void toi_read_unlock_tasklist(void);
+extern int toi_in_suspend(void);
+extern void toi_generate_free_page_map(void);
+extern int toi_size_of_free_region(struct zone *zone, unsigned long start_pfn);
+
+#ifdef CONFIG_TOI_ZRAM_SUPPORT
+extern int toi_do_flag_zram_disks(void);
+#else
+#define toi_do_flag_zram_disks() (0)
+#endif
diff --git a/kernel/power/tuxonice_checksum.c b/kernel/power/tuxonice_checksum.c
new file mode 100644
index 000000000..1c4e10c72
--- /dev/null
+++ b/kernel/power/tuxonice_checksum.c
@@ -0,0 +1,392 @@
+/*
+ * kernel/power/tuxonice_checksum.c
+ *
+ * Copyright (C) 2006-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * This file contains data checksum routines for TuxOnIce,
+ * using cryptoapi. They are used to locate any modifications
+ * made to pageset 2 while we're saving it.
+ */
+
+#include <linux/suspend.h>
+#include <linux/highmem.h>
+#include <linux/vmalloc.h>
+#include <linux/crypto.h>
+#include <linux/scatterlist.h>
+
+#include "tuxonice.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice_io.h"
+#include "tuxonice_pageflags.h"
+#include "tuxonice_checksum.h"
+#include "tuxonice_pagedir.h"
+#include "tuxonice_alloc.h"
+#include "tuxonice_ui.h"
+
+static struct toi_module_ops toi_checksum_ops;
+
+/* Constant at the mo, but I might allow tuning later */
+static char toi_checksum_name[32] = "md4";
+/* Bytes per checksum */
+#define CHECKSUM_SIZE (16)
+
+#define CHECKSUMS_PER_PAGE ((PAGE_SIZE - sizeof(void *)) / CHECKSUM_SIZE)
+
+struct cpu_context {
+        struct crypto_hash *transform;
+        struct hash_desc desc;
+        struct scatterlist sg[2];
+        char *buf;
+};
+
+static DEFINE_PER_CPU(struct cpu_context, contexts);
+static int pages_allocated;
+static unsigned long page_list;
+
+static int toi_num_resaved;
+
+static unsigned long this_checksum, next_page;
+static int checksum_count;
+
+static inline int checksum_pages_needed(void)
+{
+        return DIV_ROUND_UP(pagedir2.size, CHECKSUMS_PER_PAGE);
+}
+
+/* ---- Local buffer management ---- */
+
+/*
+ * toi_checksum_cleanup
+ *
+ * Frees memory allocated for our labours.
+ */
+static void toi_checksum_cleanup(int ending_cycle)
+{
+        int cpu;
+
+        if (ending_cycle) {
+                for_each_online_cpu(cpu) {
+                        struct cpu_context *this = &per_cpu(contexts, cpu);
+                        if (this->transform) {
+                                crypto_free_hash(this->transform);
+                                this->transform = NULL;
+                                this->desc.tfm = NULL;
+                        }
+
+                        if (this->buf) {
+                                toi_free_page(27, (unsigned long) this->buf);
+                                this->buf = NULL;
+                        }
+                }
+        }
+}
+
+/*
+ * toi_crypto_initialise
+ *
+ * Prepare to do some work by allocating buffers and transforms.
+ * Returns: Int: Zero. Even if we can't set up checksum, we still
+ * seek to hibernate.
+ */
+static int toi_checksum_initialise(int starting_cycle)
+{
+        int cpu;
+
+        if (!(starting_cycle & SYSFS_HIBERNATE) || !toi_checksum_ops.enabled)
+                return 0;
+
+        if (!*toi_checksum_name) {
+                printk(KERN_INFO "TuxOnIce: No checksum algorithm name set.\n");
+                return 1;
+        }
+
+        for_each_online_cpu(cpu) {
+                struct cpu_context *this = &per_cpu(contexts, cpu);
+                struct page *page;
+
+                this->transform = crypto_alloc_hash(toi_checksum_name, 0, 0);
+                if (IS_ERR(this->transform)) {
+                        printk(KERN_INFO "TuxOnIce: Failed to initialise the "
+                                "%s checksum algorithm: %ld.\n",
+                                toi_checksum_name, (long) this->transform);
+                        this->transform = NULL;
+                        return 1;
+                }
+
+                this->desc.tfm = this->transform;
+                this->desc.flags = 0;
+
+                page = toi_alloc_page(27, GFP_KERNEL);
+                if (!page)
+                        return 1;
+                this->buf = page_address(page);
+                sg_init_one(&this->sg[0], this->buf, PAGE_SIZE);
+        }
+        return 0;
+}
+
+/*
+ * toi_checksum_print_debug_stats
+ * @buffer: Pointer to a buffer into which the debug info will be printed.
+ * @size: Size of the buffer.
+ *
+ * Print information to be recorded for debugging purposes into a buffer.
+ * Returns: Number of characters written to the buffer.
+ */
+
+static int toi_checksum_print_debug_stats(char *buffer, int size)
+{
+        int len;
+
+        if (!toi_checksum_ops.enabled)
+                return scnprintf(buffer, size,
+                        "- Checksumming disabled.\n");
+
+        len = scnprintf(buffer, size, "- Checksum method is '%s'.\n",
+                        toi_checksum_name);
+        len += scnprintf(buffer + len, size - len,
+                "  %d pages resaved in atomic copy.\n", toi_num_resaved);
+        return len;
+}
+
+static int toi_checksum_memory_needed(void)
+{
+        return toi_checksum_ops.enabled ?
+                checksum_pages_needed() << PAGE_SHIFT : 0;
+}
+
+static int toi_checksum_storage_needed(void)
+{
+        if (toi_checksum_ops.enabled)
+                return strlen(toi_checksum_name) + sizeof(int) + 1;
+        else
+                return 0;
+}
+
+/*
+ * toi_checksum_save_config_info
+ * @buffer: Pointer to a buffer of size PAGE_SIZE.
+ *
+ * Save informaton needed when reloading the image at resume time.
+ * Returns: Number of bytes used for saving our data.
+ */
+static int toi_checksum_save_config_info(char *buffer)
+{
+        int namelen = strlen(toi_checksum_name) + 1;
+        int total_len;
+
+        *((unsigned int *) buffer) = namelen;
+        strncpy(buffer + sizeof(unsigned int), toi_checksum_name, namelen);
+        total_len = sizeof(unsigned int) + namelen;
+        return total_len;
+}
+
+/* toi_checksum_load_config_info
+ * @buffer: Pointer to the start of the data.
+ * @size: Number of bytes that were saved.
+ *
+ * Description:        Reload information needed for dechecksuming the image at
+ * resume time.
+ */
+static void toi_checksum_load_config_info(char *buffer, int size)
+{
+        int namelen;
+
+        namelen = *((unsigned int *) (buffer));
+        strncpy(toi_checksum_name, buffer + sizeof(unsigned int),
+                        namelen);
+        return;
+}
+
+/*
+ * Free Checksum Memory
+ */
+
+void free_checksum_pages(void)
+{
+        while (pages_allocated) {
+                unsigned long next = *((unsigned long *) page_list);
+                ClearPageNosave(virt_to_page(page_list));
+                toi_free_page(15, (unsigned long) page_list);
+                page_list = next;
+                pages_allocated--;
+        }
+}
+
+/*
+ * Allocate Checksum Memory
+ */
+
+int allocate_checksum_pages(void)
+{
+        int pages_needed = checksum_pages_needed();
+
+        if (!toi_checksum_ops.enabled)
+                return 0;
+
+        while (pages_allocated < pages_needed) {
+                unsigned long *new_page =
+                  (unsigned long *) toi_get_zeroed_page(15, TOI_ATOMIC_GFP);
+                if (!new_page) {
+                        printk(KERN_ERR "Unable to allocate checksum pages.\n");
+                        return -ENOMEM;
+                }
+                SetPageNosave(virt_to_page(new_page));
+                (*new_page) = page_list;
+                page_list = (unsigned long) new_page;
+                pages_allocated++;
+        }
+
+        next_page = (unsigned long) page_list;
+        checksum_count = 0;
+
+        return 0;
+}
+
+char *tuxonice_get_next_checksum(void)
+{
+        if (!toi_checksum_ops.enabled)
+                return NULL;
+
+        if (checksum_count % CHECKSUMS_PER_PAGE)
+                this_checksum += CHECKSUM_SIZE;
+        else {
+                this_checksum = next_page + sizeof(void *);
+                next_page = *((unsigned long *) next_page);
+        }
+
+        checksum_count++;
+        return (char *) this_checksum;
+}
+
+int tuxonice_calc_checksum(struct page *page, char *checksum_locn)
+{
+        char *pa;
+        int result, cpu = smp_processor_id();
+        struct cpu_context *ctx = &per_cpu(contexts, cpu);
+
+        if (!toi_checksum_ops.enabled)
+                return 0;
+
+        pa = kmap(page);
+        memcpy(ctx->buf, pa, PAGE_SIZE);
+        kunmap(page);
+        result = crypto_hash_digest(&ctx->desc, ctx->sg, PAGE_SIZE,
+                                                checksum_locn);
+        if (result)
+                printk(KERN_ERR "TuxOnIce checksumming: crypto_hash_digest "
+                                "returned %d.\n", result);
+        return result;
+}
+/*
+ * Calculate checksums
+ */
+
+void check_checksums(void)
+{
+        int index = 0, cpu = smp_processor_id();
+        char current_checksum[CHECKSUM_SIZE];
+        struct cpu_context *ctx = &per_cpu(contexts, cpu);
+        unsigned long pfn;
+
+        if (!toi_checksum_ops.enabled) {
+                toi_message(TOI_IO, TOI_VERBOSE, 0, "Checksumming disabled.");
+                return;
+        }
+
+        next_page = (unsigned long) page_list;
+
+        toi_num_resaved = 0;
+        this_checksum = 0;
+
+        toi_trace_index++;
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "Verifying checksums.");
+        memory_bm_position_reset(pageset2_map);
+        for (pfn = memory_bm_next_pfn(pageset2_map, 0); pfn != BM_END_OF_MAP;
+                        pfn = memory_bm_next_pfn(pageset2_map, 0)) {
+                int ret, resave_needed = false;
+                char *pa;
+                struct page *page = pfn_to_page(pfn);
+
+                if (index < checksum_count) {
+                    if (index % CHECKSUMS_PER_PAGE) {
+                        this_checksum += CHECKSUM_SIZE;
+                    } else {
+                        this_checksum = next_page + sizeof(void *);
+                        next_page = *((unsigned long *) next_page);
+                    }
+
+                    /* Done when IRQs disabled so must be atomic */
+                    pa = kmap_atomic(page);
+                    memcpy(ctx->buf, pa, PAGE_SIZE);
+                    kunmap_atomic(pa);
+                    ret = crypto_hash_digest(&ctx->desc, ctx->sg, PAGE_SIZE,
+                            current_checksum);
+
+                    if (ret) {
+                        printk(KERN_INFO "Digest failed. Returned %d.\n", ret);
+                        return;
+                    }
+
+                    resave_needed = memcmp(current_checksum, (char *) this_checksum,
+                            CHECKSUM_SIZE);
+                } else {
+                    resave_needed = true;
+                }
+
+                if (resave_needed) {
+                        TOI_TRACE_DEBUG(pfn, "_Resaving %d", resave_needed);
+                        SetPageResave(pfn_to_page(pfn));
+                        toi_num_resaved++;
+                        if (test_action_state(TOI_ABORT_ON_RESAVE_NEEDED))
+                                set_abort_result(TOI_RESAVE_NEEDED);
+                }
+
+                index++;
+        }
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "Checksum verification complete.");
+}
+
+static struct toi_sysfs_data sysfs_params[] = {
+        SYSFS_INT("enabled", SYSFS_RW, &toi_checksum_ops.enabled, 0, 1, 0,
+                        NULL),
+        SYSFS_BIT("abort_if_resave_needed", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_ABORT_ON_RESAVE_NEEDED, 0)
+};
+
+/*
+ * Ops structure.
+ */
+static struct toi_module_ops toi_checksum_ops = {
+        .type                        = MISC_MODULE,
+        .name                        = "checksumming",
+        .directory                = "checksum",
+        .module                        = THIS_MODULE,
+        .initialise                = toi_checksum_initialise,
+        .cleanup                = toi_checksum_cleanup,
+        .print_debug_info        = toi_checksum_print_debug_stats,
+        .save_config_info        = toi_checksum_save_config_info,
+        .load_config_info        = toi_checksum_load_config_info,
+        .memory_needed                = toi_checksum_memory_needed,
+        .storage_needed                = toi_checksum_storage_needed,
+
+        .sysfs_data                = sysfs_params,
+        .num_sysfs_entries        = sizeof(sysfs_params) /
+                sizeof(struct toi_sysfs_data),
+};
+
+/* ---- Registration ---- */
+int toi_checksum_init(void)
+{
+        int result = toi_register_module(&toi_checksum_ops);
+        return result;
+}
+
+void toi_checksum_exit(void)
+{
+        toi_unregister_module(&toi_checksum_ops);
+}
diff --git a/kernel/power/tuxonice_checksum.h b/kernel/power/tuxonice_checksum.h
new file mode 100644
index 000000000..c8196fbb0
--- /dev/null
+++ b/kernel/power/tuxonice_checksum.h
@@ -0,0 +1,31 @@
+/*
+ * kernel/power/tuxonice_checksum.h
+ *
+ * Copyright (C) 2006-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * This file contains data checksum routines for TuxOnIce,
+ * using cryptoapi. They are used to locate any modifications
+ * made to pageset 2 while we're saving it.
+ */
+
+#if defined(CONFIG_TOI_CHECKSUM)
+extern int toi_checksum_init(void);
+extern void toi_checksum_exit(void);
+void check_checksums(void);
+int allocate_checksum_pages(void);
+void free_checksum_pages(void);
+char *tuxonice_get_next_checksum(void);
+int tuxonice_calc_checksum(struct page *page, char *checksum_locn);
+#else
+static inline int toi_checksum_init(void) { return 0; }
+static inline void toi_checksum_exit(void) { }
+static inline void check_checksums(void) { };
+static inline int allocate_checksum_pages(void) { return 0; };
+static inline void free_checksum_pages(void) { };
+static inline char *tuxonice_get_next_checksum(void) { return NULL; };
+static inline int tuxonice_calc_checksum(struct page *page, char *checksum_locn)
+        { return 0; }
+#endif
+
diff --git a/kernel/power/tuxonice_cluster.c b/kernel/power/tuxonice_cluster.c
new file mode 100644
index 000000000..2873f93c6
--- /dev/null
+++ b/kernel/power/tuxonice_cluster.c
@@ -0,0 +1,1058 @@
+/*
+ * kernel/power/tuxonice_cluster.c
+ *
+ * Copyright (C) 2006-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * This file contains routines for cluster hibernation support.
+ *
+ * Based on ip autoconfiguration code in net/ipv4/ipconfig.c.
+ *
+ * How does it work?
+ *
+ * There is no 'master' node that tells everyone else what to do. All nodes
+ * send messages to the broadcast address/port, maintain a list of peers
+ * and figure out when to progress to the next step in hibernating or resuming.
+ * This makes us more fault tolerant when it comes to nodes coming and going
+ * (which may be more of an issue if we're hibernating when power supplies
+ * are being unreliable).
+ *
+ * At boot time, we start a ktuxonice thread that handles communication with
+ * other nodes. This node maintains a state machine that controls our progress
+ * through hibernating and resuming, keeping us in step with other nodes. Nodes
+ * are identified by their hw address.
+ *
+ * On startup, the node sends CLUSTER_PING on the configured interface's
+ * broadcast address, port $toi_cluster_port (see below) and begins to listen
+ * for other broadcast messages. CLUSTER_PING messages are repeated at
+ * intervals of 5 minutes, with a random offset to spread traffic out.
+ *
+ * A hibernation cycle is initiated from any node via
+ *
+ * echo > /sys/power/tuxonice/do_hibernate
+ *
+ * and (possibily) the hibernate script. At each step of the process, the node
+ * completes its work, and waits for all other nodes to signal completion of
+ * their work (or timeout) before progressing to the next step.
+ *
+ * Request/state  Action before reply        Possible reply        Next state
+ * HIBERNATE          capable, pre-script        HIBERNATE|ACK        NODE_PREP
+ *                                         HIBERNATE|NACK        INIT_0
+ *
+ * PREP                  prepare_image                PREP|ACK        IMAGE_WRITE
+ *                                         PREP|NACK        INIT_0
+ *                                         ABORT                RUNNING
+ *
+ * IO                  write image                IO|ACK                power off
+ *                                         ABORT                POST_RESUME
+ *
+ * (Boot time)          check for image        IMAGE|ACK        RESUME_PREP
+ *                                         (Note 1)
+ *                                         IMAGE|NACK        (Note 2)
+ *
+ * PREP                  prepare read image        PREP|ACK        IMAGE_READ
+ *                                         PREP|NACK        (As NACK_IMAGE)
+ *
+ * IO                  read image                IO|ACK                POST_RESUME
+ *
+ * POST_RESUME          thaw, post-script                        RUNNING
+ *
+ * INIT_0          init 0
+ *
+ * Other messages:
+ *
+ * - PING: Request for all other live nodes to send a PONG. Used at startup to
+ *   announce presence, when a node is suspected dead and periodically, in case
+ *   segments of the network are [un]plugged.
+ *
+ * - PONG: Response to a PING.
+ *
+ * - ABORT: Request to cancel writing an image.
+ *
+ * - BYE: Notification that this node is shutting down.
+ *
+ * Note 1: Repeated at 3s intervals until we continue to boot/resume, so that
+ * nodes which are slower to start up can get state synchronised. If a node
+ * starting up sees other nodes sending RESUME_PREP or IMAGE_READ, it may send
+ * ACK_IMAGE and they will wait for it to catch up. If it sees ACK_READ, it
+ * must invalidate its image (if any) and boot normally.
+ *
+ * Note 2: May occur when one node lost power or powered off while others
+ * hibernated. This node waits for others to complete resuming (ACK_READ)
+ * before completing its boot, so that it appears as a fail node restarting.
+ *
+ * If any node has an image, then it also has a list of nodes that hibernated
+ * in synchronisation with it. The node will wait for other nodes to appear
+ * or timeout before beginning its restoration.
+ *
+ * If a node has no image, it needs to wait, in case other nodes which do have
+ * an image are going to resume, but are taking longer to announce their
+ * presence. For this reason, the user can specify a timeout value and a number
+ * of nodes detected before we just continue. (We might want to assume in a
+ * cluster of, say, 15 nodes, if 8 others have booted without finding an image,
+ * the remaining nodes will too. This might help in situations where some nodes
+ * are much slower to boot, or more subject to hardware failures or such like).
+ */
+
+#include <linux/suspend.h>
+#include <linux/if.h>
+#include <linux/rtnetlink.h>
+#include <linux/ip.h>
+#include <linux/udp.h>
+#include <linux/in.h>
+#include <linux/if_arp.h>
+#include <linux/kthread.h>
+#include <linux/wait.h>
+#include <linux/netdevice.h>
+#include <net/ip.h>
+
+#include "tuxonice.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice_alloc.h"
+#include "tuxonice_io.h"
+
+#if 1
+#define PRINTK(a, b...) do { printk(a, ##b); } while (0)
+#else
+#define PRINTK(a, b...) do { } while (0)
+#endif
+
+static int loopback_mode;
+static int num_local_nodes = 1;
+#define MAX_LOCAL_NODES 8
+#define SADDR (loopback_mode ? b->sid : h->saddr)
+
+#define MYNAME "TuxOnIce Clustering"
+
+enum cluster_message {
+        MSG_ACK = 1,
+        MSG_NACK = 2,
+        MSG_PING = 4,
+        MSG_ABORT = 8,
+        MSG_BYE = 16,
+        MSG_HIBERNATE = 32,
+        MSG_IMAGE = 64,
+        MSG_IO = 128,
+        MSG_RUNNING = 256
+};
+
+static char *str_message(int message)
+{
+        switch (message) {
+        case 4:
+                return "Ping";
+        case 8:
+                return "Abort";
+        case 9:
+                return "Abort acked";
+        case 10:
+                return "Abort nacked";
+        case 16:
+                return "Bye";
+        case 17:
+                return "Bye acked";
+        case 18:
+                return "Bye nacked";
+        case 32:
+                return "Hibernate request";
+        case 33:
+                return "Hibernate ack";
+        case 34:
+                return "Hibernate nack";
+        case 64:
+                return "Image exists?";
+        case 65:
+                return "Image does exist";
+        case 66:
+                return "No image here";
+        case 128:
+                return "I/O";
+        case 129:
+                return "I/O okay";
+        case 130:
+                return "I/O failed";
+        case 256:
+                return "Running";
+        default:
+                printk(KERN_ERR "Unrecognised message %d.\n", message);
+                return "Unrecognised message (see dmesg)";
+        }
+}
+
+#define MSG_ACK_MASK (MSG_ACK | MSG_NACK)
+#define MSG_STATE_MASK (~MSG_ACK_MASK)
+
+struct node_info {
+        struct list_head member_list;
+        wait_queue_head_t member_events;
+        spinlock_t member_list_lock;
+        spinlock_t receive_lock;
+        int peer_count, ignored_peer_count;
+        struct toi_sysfs_data sysfs_data;
+        enum cluster_message current_message;
+};
+
+struct node_info node_array[MAX_LOCAL_NODES];
+
+struct cluster_member {
+        __be32 addr;
+        enum cluster_message message;
+        struct list_head list;
+        int ignore;
+};
+
+#define toi_cluster_port_send 3501
+#define toi_cluster_port_recv 3502
+
+static struct net_device *net_dev;
+static struct toi_module_ops toi_cluster_ops;
+
+static int toi_recv(struct sk_buff *skb, struct net_device *dev,
+                struct packet_type *pt, struct net_device *orig_dev);
+
+static struct packet_type toi_cluster_packet_type = {
+        .type =        __constant_htons(ETH_P_IP),
+        .func =        toi_recv,
+};
+
+struct toi_pkt {                /* BOOTP packet format */
+        struct iphdr iph;        /* IP header */
+        struct udphdr udph;        /* UDP header */
+        u8 htype;                /* HW address type */
+        u8 hlen;                /* HW address length */
+        __be32 xid;                /* Transaction ID */
+        __be16 secs;                /* Seconds since we started */
+        __be16 flags;                /* Just what it says */
+        u8 hw_addr[16];                /* Sender's HW address */
+        u16 message;                /* Message */
+        unsigned long sid;        /* Source ID for loopback testing */
+};
+
+static char toi_cluster_iface[IFNAMSIZ] = CONFIG_TOI_DEFAULT_CLUSTER_INTERFACE;
+
+static int added_pack;
+
+static int others_have_image;
+
+/* Key used to allow multiple clusters on the same lan */
+static char toi_cluster_key[32] = CONFIG_TOI_DEFAULT_CLUSTER_KEY;
+static char pre_hibernate_script[255] =
+        CONFIG_TOI_DEFAULT_CLUSTER_PRE_HIBERNATE;
+static char post_hibernate_script[255] =
+        CONFIG_TOI_DEFAULT_CLUSTER_POST_HIBERNATE;
+
+/*                        List of cluster members                        */
+static unsigned long continue_delay = 5 * HZ;
+static unsigned long cluster_message_timeout = 3 * HZ;
+
+/*                 === Membership list ===         */
+
+static void print_member_info(int index)
+{
+        struct cluster_member *this;
+
+        printk(KERN_INFO "==> Dumping node %d.\n", index);
+
+        list_for_each_entry(this, &node_array[index].member_list, list)
+                printk(KERN_INFO "%d.%d.%d.%d last message %s. %s\n",
+                                NIPQUAD(this->addr),
+                                str_message(this->message),
+                                this->ignore ? "(Ignored)" : "");
+        printk(KERN_INFO "== Done ==\n");
+}
+
+static struct cluster_member *__find_member(int index, __be32 addr)
+{
+        struct cluster_member *this;
+
+        list_for_each_entry(this, &node_array[index].member_list, list) {
+                if (this->addr != addr)
+                        continue;
+
+                return this;
+        }
+
+        return NULL;
+}
+
+static void set_ignore(int index, __be32 addr, struct cluster_member *this)
+{
+        if (this->ignore) {
+                PRINTK("Node %d already ignoring %d.%d.%d.%d.\n",
+                                index, NIPQUAD(addr));
+                return;
+        }
+
+        PRINTK("Node %d sees node %d.%d.%d.%d now being ignored.\n",
+                                index, NIPQUAD(addr));
+        this->ignore = 1;
+        node_array[index].ignored_peer_count++;
+}
+
+static int __add_update_member(int index, __be32 addr, int message)
+{
+        struct cluster_member *this;
+
+        this = __find_member(index, addr);
+        if (this) {
+                if (this->message != message) {
+                        this->message = message;
+                        if ((message & MSG_NACK) &&
+                            (message & (MSG_HIBERNATE | MSG_IMAGE | MSG_IO)))
+                                set_ignore(index, addr, this);
+                        PRINTK("Node %d sees node %d.%d.%d.%d now sending "
+                                        "%s.\n", index, NIPQUAD(addr),
+                                        str_message(message));
+                        wake_up(&node_array[index].member_events);
+                }
+                return 0;
+        }
+
+        this = (struct cluster_member *) toi_kzalloc(36,
+                        sizeof(struct cluster_member), GFP_KERNEL);
+
+        if (!this)
+                return -1;
+
+        this->addr = addr;
+        this->message = message;
+        this->ignore = 0;
+        INIT_LIST_HEAD(&this->list);
+
+        node_array[index].peer_count++;
+
+        PRINTK("Node %d sees node %d.%d.%d.%d sending %s.\n", index,
+                        NIPQUAD(addr), str_message(message));
+
+        if ((message & MSG_NACK) &&
+            (message & (MSG_HIBERNATE | MSG_IMAGE | MSG_IO)))
+                set_ignore(index, addr, this);
+        list_add_tail(&this->list, &node_array[index].member_list);
+        return 1;
+}
+
+static int add_update_member(int index, __be32 addr, int message)
+{
+        int result;
+        unsigned long flags;
+        spin_lock_irqsave(&node_array[index].member_list_lock, flags);
+        result = __add_update_member(index, addr, message);
+        spin_unlock_irqrestore(&node_array[index].member_list_lock, flags);
+
+        print_member_info(index);
+
+        wake_up(&node_array[index].member_events);
+
+        return result;
+}
+
+static void del_member(int index, __be32 addr)
+{
+        struct cluster_member *this;
+        unsigned long flags;
+
+        spin_lock_irqsave(&node_array[index].member_list_lock, flags);
+        this = __find_member(index, addr);
+
+        if (this) {
+                list_del_init(&this->list);
+                toi_kfree(36, this, sizeof(*this));
+                node_array[index].peer_count--;
+        }
+
+        spin_unlock_irqrestore(&node_array[index].member_list_lock, flags);
+}
+
+/*                 === Message transmission ===        */
+
+static void toi_send_if(int message, unsigned long my_id);
+
+/*
+ *  Process received TOI packet.
+ */
+static int toi_recv(struct sk_buff *skb, struct net_device *dev,
+                struct packet_type *pt, struct net_device *orig_dev)
+{
+        struct toi_pkt *b;
+        struct iphdr *h;
+        int len, result, index;
+        unsigned long addr, message, ack;
+
+        /* Perform verifications before taking the lock.  */
+        if (skb->pkt_type == PACKET_OTHERHOST)
+                goto drop;
+
+        if (dev != net_dev)
+                goto drop;
+
+        skb = skb_share_check(skb, GFP_ATOMIC);
+        if (!skb)
+                return NET_RX_DROP;
+
+        if (!pskb_may_pull(skb,
+                           sizeof(struct iphdr) +
+                           sizeof(struct udphdr)))
+                goto drop;
+
+        b = (struct toi_pkt *)skb_network_header(skb);
+        h = &b->iph;
+
+        if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
+                goto drop;
+
+        /* Fragments are not supported */
+        if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
+                if (net_ratelimit())
+                        printk(KERN_ERR "TuxOnIce: Ignoring fragmented "
+                               "cluster message.\n");
+                goto drop;
+        }
+
+        if (skb->len < ntohs(h->tot_len))
+                goto drop;
+
+        if (ip_fast_csum((char *) h, h->ihl))
+                goto drop;
+
+        if (b->udph.source != htons(toi_cluster_port_send) ||
+            b->udph.dest != htons(toi_cluster_port_recv))
+                goto drop;
+
+        if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
+                goto drop;
+
+        len = ntohs(b->udph.len) - sizeof(struct udphdr);
+
+        /* Ok the front looks good, make sure we can get at the rest.  */
+        if (!pskb_may_pull(skb, skb->len))
+                goto drop;
+
+        b = (struct toi_pkt *)skb_network_header(skb);
+        h = &b->iph;
+
+        addr = SADDR;
+        PRINTK(">>> Message %s received from " NIPQUAD_FMT ".\n",
+                        str_message(b->message), NIPQUAD(addr));
+
+        message = b->message & MSG_STATE_MASK;
+        ack = b->message & MSG_ACK_MASK;
+
+        for (index = 0; index < num_local_nodes; index++) {
+                int new_message = node_array[index].current_message,
+                    old_message = new_message;
+
+                if (index == SADDR || !old_message) {
+                        PRINTK("Ignoring node %d (offline or self).\n", index);
+                        continue;
+                }
+
+                /* One message at a time, please. */
+                spin_lock(&node_array[index].receive_lock);
+
+                result = add_update_member(index, SADDR, b->message);
+                if (result == -1) {
+                        printk(KERN_INFO "Failed to add new cluster member "
+                                        NIPQUAD_FMT ".\n",
+                                        NIPQUAD(addr));
+                        goto drop_unlock;
+                }
+
+                switch (b->message & MSG_STATE_MASK) {
+                case MSG_PING:
+                        break;
+                case MSG_ABORT:
+                        break;
+                case MSG_BYE:
+                        break;
+                case MSG_HIBERNATE:
+                        /* Can I hibernate? */
+                        new_message = MSG_HIBERNATE |
+                                ((index & 1) ? MSG_NACK : MSG_ACK);
+                        break;
+                case MSG_IMAGE:
+                        /* Can I resume? */
+                        new_message = MSG_IMAGE |
+                                ((index & 1) ? MSG_NACK : MSG_ACK);
+                        if (new_message != old_message)
+                                printk(KERN_ERR "Setting whether I can resume "
+                                                "to %d.\n", new_message);
+                        break;
+                case MSG_IO:
+                        new_message = MSG_IO | MSG_ACK;
+                        break;
+                case MSG_RUNNING:
+                        break;
+                default:
+                        if (net_ratelimit())
+                                printk(KERN_ERR "Unrecognised TuxOnIce cluster"
+                                        " message %d from " NIPQUAD_FMT ".\n",
+                                        b->message, NIPQUAD(addr));
+                };
+
+                if (old_message != new_message) {
+                        node_array[index].current_message = new_message;
+                        printk(KERN_INFO ">>> Sending new message for node "
+                                        "%d.\n", index);
+                        toi_send_if(new_message, index);
+                } else if (!ack) {
+                        printk(KERN_INFO ">>> Resending message for node %d.\n",
+                                        index);
+                        toi_send_if(new_message, index);
+                }
+drop_unlock:
+                spin_unlock(&node_array[index].receive_lock);
+        };
+
+drop:
+        /* Throw the packet out. */
+        kfree_skb(skb);
+
+        return 0;
+}
+
+/*
+ *  Send cluster message to single interface.
+ */
+static void toi_send_if(int message, unsigned long my_id)
+{
+        struct sk_buff *skb;
+        struct toi_pkt *b;
+        int hh_len = LL_RESERVED_SPACE(net_dev);
+        struct iphdr *h;
+
+        /* Allocate packet */
+        skb = alloc_skb(sizeof(struct toi_pkt) + hh_len + 15, GFP_KERNEL);
+        if (!skb)
+                return;
+        skb_reserve(skb, hh_len);
+        b = (struct toi_pkt *) skb_put(skb, sizeof(struct toi_pkt));
+        memset(b, 0, sizeof(struct toi_pkt));
+
+        /* Construct IP header */
+        skb_reset_network_header(skb);
+        h = ip_hdr(skb);
+        h->version = 4;
+        h->ihl = 5;
+        h->tot_len = htons(sizeof(struct toi_pkt));
+        h->frag_off = htons(IP_DF);
+        h->ttl = 64;
+        h->protocol = IPPROTO_UDP;
+        h->daddr = htonl(INADDR_BROADCAST);
+        h->check = ip_fast_csum((unsigned char *) h, h->ihl);
+
+        /* Construct UDP header */
+        b->udph.source = htons(toi_cluster_port_send);
+        b->udph.dest = htons(toi_cluster_port_recv);
+        b->udph.len = htons(sizeof(struct toi_pkt) - sizeof(struct iphdr));
+        /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
+
+        /* Construct message */
+        b->message = message;
+        b->sid = my_id;
+        b->htype = net_dev->type; /* can cause undefined behavior */
+        b->hlen = net_dev->addr_len;
+        memcpy(b->hw_addr, net_dev->dev_addr, net_dev->addr_len);
+        b->secs = htons(3); /* 3 seconds */
+
+        /* Chain packet down the line... */
+        skb->dev = net_dev;
+        skb->protocol = htons(ETH_P_IP);
+        if ((dev_hard_header(skb, net_dev, ntohs(skb->protocol),
+                     net_dev->broadcast, net_dev->dev_addr, skb->len) < 0) ||
+                        dev_queue_xmit(skb) < 0)
+                printk(KERN_INFO "E");
+}
+
+/*        =========================================                */
+
+/*                        kTOICluster                        */
+
+static atomic_t num_cluster_threads;
+static DECLARE_WAIT_QUEUE_HEAD(clusterd_events);
+
+static int kTOICluster(void *data)
+{
+        unsigned long my_id;
+
+        my_id = atomic_add_return(1, &num_cluster_threads) - 1;
+        node_array[my_id].current_message = (unsigned long) data;
+
+        PRINTK("kTOICluster daemon %lu starting.\n", my_id);
+
+        current->flags |= PF_NOFREEZE;
+
+        while (node_array[my_id].current_message) {
+                toi_send_if(node_array[my_id].current_message, my_id);
+                sleep_on_timeout(&clusterd_events,
+                                cluster_message_timeout);
+                PRINTK("Link state %lu is %d.\n", my_id,
+                                node_array[my_id].current_message);
+        }
+
+        toi_send_if(MSG_BYE, my_id);
+        atomic_dec(&num_cluster_threads);
+        wake_up(&clusterd_events);
+
+        PRINTK("kTOICluster daemon %lu exiting.\n", my_id);
+        __set_current_state(TASK_RUNNING);
+        return 0;
+}
+
+static void kill_clusterd(void)
+{
+        int i;
+
+        for (i = 0; i < num_local_nodes; i++) {
+                if (node_array[i].current_message) {
+                        PRINTK("Seeking to kill clusterd %d.\n", i);
+                        node_array[i].current_message = 0;
+                }
+        }
+        wait_event(clusterd_events,
+                        !atomic_read(&num_cluster_threads));
+        PRINTK("All cluster daemons have exited.\n");
+}
+
+static int peers_not_in_message(int index, int message, int precise)
+{
+        struct cluster_member *this;
+        unsigned long flags;
+        int result = 0;
+
+        spin_lock_irqsave(&node_array[index].member_list_lock, flags);
+        list_for_each_entry(this, &node_array[index].member_list, list) {
+                if (this->ignore)
+                        continue;
+
+                PRINTK("Peer %d.%d.%d.%d sending %s. "
+                        "Seeking %s.\n",
+                        NIPQUAD(this->addr),
+                        str_message(this->message), str_message(message));
+                if ((precise ? this->message :
+                                        this->message & MSG_STATE_MASK) !=
+                                        message)
+                        result++;
+        }
+        spin_unlock_irqrestore(&node_array[index].member_list_lock, flags);
+        PRINTK("%d peers in sought message.\n", result);
+        return result;
+}
+
+static void reset_ignored(int index)
+{
+        struct cluster_member *this;
+        unsigned long flags;
+
+        spin_lock_irqsave(&node_array[index].member_list_lock, flags);
+        list_for_each_entry(this, &node_array[index].member_list, list)
+                this->ignore = 0;
+        node_array[index].ignored_peer_count = 0;
+        spin_unlock_irqrestore(&node_array[index].member_list_lock, flags);
+}
+
+static int peers_in_message(int index, int message, int precise)
+{
+        return node_array[index].peer_count -
+                node_array[index].ignored_peer_count -
+                peers_not_in_message(index, message, precise);
+}
+
+static int time_to_continue(int index, unsigned long start, int message)
+{
+        int first = peers_not_in_message(index, message, 0);
+        int second = peers_in_message(index, message, 1);
+
+        PRINTK("First part returns %d, second returns %d.\n", first, second);
+
+        if (!first && !second) {
+                PRINTK("All peers answered message %d.\n",
+                        message);
+                return 1;
+        }
+
+        if (time_after(jiffies, start + continue_delay)) {
+                PRINTK("Timeout reached.\n");
+                return 1;
+        }
+
+        PRINTK("Not time to continue yet (%lu < %lu).\n", jiffies,
+                        start + continue_delay);
+        return 0;
+}
+
+void toi_initiate_cluster_hibernate(void)
+{
+        int result;
+        unsigned long start;
+
+        result = do_toi_step(STEP_HIBERNATE_PREPARE_IMAGE);
+        if (result)
+                return;
+
+        toi_send_if(MSG_HIBERNATE, 0);
+
+        start = jiffies;
+        wait_event(node_array[0].member_events,
+                        time_to_continue(0, start, MSG_HIBERNATE));
+
+        if (test_action_state(TOI_FREEZER_TEST)) {
+                toi_send_if(MSG_ABORT, 0);
+
+                start = jiffies;
+                wait_event(node_array[0].member_events,
+                        time_to_continue(0, start, MSG_RUNNING));
+
+                do_toi_step(STEP_QUIET_CLEANUP);
+                return;
+        }
+
+        toi_send_if(MSG_IO, 0);
+
+        result = do_toi_step(STEP_HIBERNATE_SAVE_IMAGE);
+        if (result)
+                return;
+
+        /* This code runs at resume time too! */
+        if (toi_in_hibernate)
+                result = do_toi_step(STEP_HIBERNATE_POWERDOWN);
+}
+
+/* toi_cluster_print_debug_stats
+ *
+ * Description:        Print information to be recorded for debugging purposes into a
+ *                 buffer.
+ * Arguments:        buffer: Pointer to a buffer into which the debug info will be
+ *                         printed.
+ *                 size:        Size of the buffer.
+ * Returns:        Number of characters written to the buffer.
+ */
+static int toi_cluster_print_debug_stats(char *buffer, int size)
+{
+        int len;
+
+        if (strlen(toi_cluster_iface))
+                len = scnprintf(buffer, size,
+                                "- Cluster interface is '%s'.\n",
+                                toi_cluster_iface);
+        else
+                len = scnprintf(buffer, size,
+                                "- Cluster support is disabled.\n");
+        return len;
+}
+
+/* cluster_memory_needed
+ *
+ * Description:        Tell the caller how much memory we need to operate during
+ *                 hibernate/resume.
+ * Returns:        Unsigned long. Maximum number of bytes of memory required for
+ *                 operation.
+ */
+static int toi_cluster_memory_needed(void)
+{
+        return 0;
+}
+
+static int toi_cluster_storage_needed(void)
+{
+        return 1 + strlen(toi_cluster_iface);
+}
+
+/* toi_cluster_save_config_info
+ *
+ * Description:        Save informaton needed when reloading the image at resume time.
+ * Arguments:        Buffer:                Pointer to a buffer of size PAGE_SIZE.
+ * Returns:        Number of bytes used for saving our data.
+ */
+static int toi_cluster_save_config_info(char *buffer)
+{
+        strcpy(buffer, toi_cluster_iface);
+        return strlen(toi_cluster_iface + 1);
+}
+
+/* toi_cluster_load_config_info
+ *
+ * Description:        Reload information needed for declustering the image at
+ *                 resume time.
+ * Arguments:        Buffer:                Pointer to the start of the data.
+ *                Size:                Number of bytes that were saved.
+ */
+static void toi_cluster_load_config_info(char *buffer, int size)
+{
+        strncpy(toi_cluster_iface, buffer, size);
+        return;
+}
+
+static void cluster_startup(void)
+{
+        int have_image = do_check_can_resume(), i;
+        unsigned long start = jiffies, initial_message;
+        struct task_struct *p;
+
+        initial_message = MSG_IMAGE;
+
+        have_image = 1;
+
+        for (i = 0; i < num_local_nodes; i++) {
+                PRINTK("Starting ktoiclusterd %d.\n", i);
+                p = kthread_create(kTOICluster, (void *) initial_message,
+                                "ktoiclusterd/%d", i);
+                if (IS_ERR(p)) {
+                        printk(KERN_ERR "Failed to start ktoiclusterd.\n");
+                        return;
+                }
+
+                wake_up_process(p);
+        }
+
+        /* Wait for delay or someone else sending first message */
+        wait_event(node_array[0].member_events, time_to_continue(0, start,
+                                MSG_IMAGE));
+
+        others_have_image = peers_in_message(0, MSG_IMAGE | MSG_ACK, 1);
+
+        printk(KERN_INFO "Continuing. I %shave an image. Peers with image:"
+                " %d.\n", have_image ? "" : "don't ", others_have_image);
+
+        if (have_image) {
+                int result;
+
+                /* Start to resume */
+                printk(KERN_INFO "  === Starting to resume ===  \n");
+                node_array[0].current_message = MSG_IO;
+                toi_send_if(MSG_IO, 0);
+
+                /* result = do_toi_step(STEP_RESUME_LOAD_PS1); */
+                result = 0;
+
+                if (!result) {
+                        /*
+                         * Atomic restore - we'll come back in the hibernation
+                         * path.
+                         */
+
+                        /* result = do_toi_step(STEP_RESUME_DO_RESTORE); */
+                        result = 0;
+
+                        /* do_toi_step(STEP_QUIET_CLEANUP); */
+                }
+
+                node_array[0].current_message |= MSG_NACK;
+
+                /* For debugging - disable for real life? */
+                wait_event(node_array[0].member_events,
+                                time_to_continue(0, start, MSG_IO));
+        }
+
+        if (others_have_image) {
+                /* Wait for them to resume */
+                printk(KERN_INFO "Waiting for other nodes to resume.\n");
+                start = jiffies;
+                wait_event(node_array[0].member_events,
+                                time_to_continue(0, start, MSG_RUNNING));
+                if (peers_not_in_message(0, MSG_RUNNING, 0))
+                        printk(KERN_INFO "Timed out while waiting for other "
+                                        "nodes to resume.\n");
+        }
+
+        /* Find out whether an image exists here. Send ACK_IMAGE or NACK_IMAGE
+         * as appropriate.
+         *
+         * If we don't have an image:
+         * - Wait until someone else says they have one, or conditions are met
+         *   for continuing to boot (n machines or t seconds).
+         * - If anyone has an image, wait for them to resume before continuing
+         *   to boot.
+         *
+         * If we have an image:
+         * - Wait until conditions are met before continuing to resume (n
+         *   machines or t seconds). Send RESUME_PREP and freeze processes.
+         *   NACK_PREP if freezing fails (shouldn't) and follow logic for
+         *   us having no image above. On success, wait for [N]ACK_PREP from
+         *   other machines. Read image (including atomic restore) until done.
+         *   Wait for ACK_READ from others (should never fail). Thaw processes
+         *   and do post-resume. (The section after the atomic restore is done
+         *   via the code for hibernating).
+         */
+
+        node_array[0].current_message = MSG_RUNNING;
+}
+
+/* toi_cluster_open_iface
+ *
+ * Description:        Prepare to use an interface.
+ */
+
+static int toi_cluster_open_iface(void)
+{
+        struct net_device *dev;
+
+        rtnl_lock();
+
+        for_each_netdev(&init_net, dev) {
+                if (/* dev == &init_net.loopback_dev || */
+                    strcmp(dev->name, toi_cluster_iface))
+                        continue;
+
+                net_dev = dev;
+                break;
+        }
+
+        rtnl_unlock();
+
+        if (!net_dev) {
+                printk(KERN_ERR MYNAME ": Device %s not found.\n",
+                                toi_cluster_iface);
+                return -ENODEV;
+        }
+
+        dev_add_pack(&toi_cluster_packet_type);
+        added_pack = 1;
+
+        loopback_mode = (net_dev == init_net.loopback_dev);
+        num_local_nodes = loopback_mode ? 8 : 1;
+
+        PRINTK("Loopback mode is %s. Number of local nodes is %d.\n",
+                        loopback_mode ? "on" : "off", num_local_nodes);
+
+        cluster_startup();
+        return 0;
+}
+
+/* toi_cluster_close_iface
+ *
+ * Description: Stop using an interface.
+ */
+
+static int toi_cluster_close_iface(void)
+{
+        kill_clusterd();
+        if (added_pack) {
+                dev_remove_pack(&toi_cluster_packet_type);
+                added_pack = 0;
+        }
+        return 0;
+}
+
+static void write_side_effect(void)
+{
+        if (toi_cluster_ops.enabled) {
+                toi_cluster_open_iface();
+                set_toi_state(TOI_CLUSTER_MODE);
+        } else {
+                toi_cluster_close_iface();
+                clear_toi_state(TOI_CLUSTER_MODE);
+        }
+}
+
+static void node_write_side_effect(void)
+{
+}
+
+/*
+ * data for our sysfs entries.
+ */
+static struct toi_sysfs_data sysfs_params[] = {
+        SYSFS_STRING("interface", SYSFS_RW, toi_cluster_iface, IFNAMSIZ, 0,
+                        NULL),
+        SYSFS_INT("enabled", SYSFS_RW, &toi_cluster_ops.enabled, 0, 1, 0,
+                        write_side_effect),
+        SYSFS_STRING("cluster_name", SYSFS_RW, toi_cluster_key, 32, 0, NULL),
+        SYSFS_STRING("pre-hibernate-script", SYSFS_RW, pre_hibernate_script,
+                        256, 0, NULL),
+        SYSFS_STRING("post-hibernate-script", SYSFS_RW, post_hibernate_script,
+                        256, 0, STRING),
+        SYSFS_UL("continue_delay", SYSFS_RW, &continue_delay, HZ / 2, 60 * HZ,
+                        0)
+};
+
+/*
+ * Ops structure.
+ */
+
+static struct toi_module_ops toi_cluster_ops = {
+        .type                        = FILTER_MODULE,
+        .name                        = "Cluster",
+        .directory                = "cluster",
+        .module                        = THIS_MODULE,
+        .memory_needed                 = toi_cluster_memory_needed,
+        .print_debug_info        = toi_cluster_print_debug_stats,
+        .save_config_info        = toi_cluster_save_config_info,
+        .load_config_info        = toi_cluster_load_config_info,
+        .storage_needed                = toi_cluster_storage_needed,
+
+        .sysfs_data                = sysfs_params,
+        .num_sysfs_entries        = sizeof(sysfs_params) /
+                sizeof(struct toi_sysfs_data),
+};
+
+/* ---- Registration ---- */
+
+#ifdef MODULE
+#define INIT static __init
+#define EXIT static __exit
+#else
+#define INIT
+#define EXIT
+#endif
+
+INIT int toi_cluster_init(void)
+{
+        int temp = toi_register_module(&toi_cluster_ops), i;
+        struct kobject *kobj = toi_cluster_ops.dir_kobj;
+
+        for (i = 0; i < MAX_LOCAL_NODES; i++) {
+                node_array[i].current_message = 0;
+                INIT_LIST_HEAD(&node_array[i].member_list);
+                init_waitqueue_head(&node_array[i].member_events);
+                spin_lock_init(&node_array[i].member_list_lock);
+                spin_lock_init(&node_array[i].receive_lock);
+
+                /* Set up sysfs entry */
+                node_array[i].sysfs_data.attr.name = toi_kzalloc(8,
+                                sizeof(node_array[i].sysfs_data.attr.name),
+                                GFP_KERNEL);
+                sprintf((char *) node_array[i].sysfs_data.attr.name, "node_%d",
+                                i);
+                node_array[i].sysfs_data.attr.mode = SYSFS_RW;
+                node_array[i].sysfs_data.type = TOI_SYSFS_DATA_INTEGER;
+                node_array[i].sysfs_data.flags = 0;
+                node_array[i].sysfs_data.data.integer.variable =
+                        (int *) &node_array[i].current_message;
+                node_array[i].sysfs_data.data.integer.minimum = 0;
+                node_array[i].sysfs_data.data.integer.maximum = INT_MAX;
+                node_array[i].sysfs_data.write_side_effect =
+                        node_write_side_effect;
+                toi_register_sysfs_file(kobj, &node_array[i].sysfs_data);
+        }
+
+        toi_cluster_ops.enabled = (strlen(toi_cluster_iface) > 0);
+
+        if (toi_cluster_ops.enabled)
+                toi_cluster_open_iface();
+
+        return temp;
+}
+
+EXIT void toi_cluster_exit(void)
+{
+        int i;
+        toi_cluster_close_iface();
+
+        for (i = 0; i < MAX_LOCAL_NODES; i++)
+                toi_unregister_sysfs_file(toi_cluster_ops.dir_kobj,
+                                &node_array[i].sysfs_data);
+        toi_unregister_module(&toi_cluster_ops);
+}
+
+static int __init toi_cluster_iface_setup(char *iface)
+{
+        toi_cluster_ops.enabled = (*iface &&
+                        strcmp(iface, "off"));
+
+        if (toi_cluster_ops.enabled)
+                strncpy(toi_cluster_iface, iface, strlen(iface));
+}
+
+__setup("toi_cluster=", toi_cluster_iface_setup);
diff --git a/kernel/power/tuxonice_cluster.h b/kernel/power/tuxonice_cluster.h
new file mode 100644
index 000000000..84356b304
--- /dev/null
+++ b/kernel/power/tuxonice_cluster.h
@@ -0,0 +1,18 @@
+/*
+ * kernel/power/tuxonice_cluster.h
+ *
+ * Copyright (C) 2006-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ */
+
+#ifdef CONFIG_TOI_CLUSTER
+extern int toi_cluster_init(void);
+extern void toi_cluster_exit(void);
+extern void toi_initiate_cluster_hibernate(void);
+#else
+static inline int toi_cluster_init(void) { return 0; }
+static inline void toi_cluster_exit(void) { }
+static inline void toi_initiate_cluster_hibernate(void) { }
+#endif
+
diff --git a/kernel/power/tuxonice_compress.c b/kernel/power/tuxonice_compress.c
new file mode 100644
index 000000000..84b85226d
--- /dev/null
+++ b/kernel/power/tuxonice_compress.c
@@ -0,0 +1,452 @@
+/*
+ * kernel/power/compression.c
+ *
+ * Copyright (C) 2003-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * This file contains data compression routines for TuxOnIce,
+ * using cryptoapi.
+ */
+
+#include <linux/suspend.h>
+#include <linux/highmem.h>
+#include <linux/vmalloc.h>
+#include <linux/crypto.h>
+
+#include "tuxonice_builtin.h"
+#include "tuxonice.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice_io.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_alloc.h"
+
+static int toi_expected_compression;
+
+static struct toi_module_ops toi_compression_ops;
+static struct toi_module_ops *next_driver;
+
+static char toi_compressor_name[32] = "lzo";
+
+static DEFINE_MUTEX(stats_lock);
+
+struct cpu_context {
+        u8 *page_buffer;
+        struct crypto_comp *transform;
+        unsigned int len;
+        u8 *buffer_start;
+        u8 *output_buffer;
+};
+
+#define OUT_BUF_SIZE (2 * PAGE_SIZE)
+
+static DEFINE_PER_CPU(struct cpu_context, contexts);
+
+/*
+ * toi_crypto_prepare
+ *
+ * Prepare to do some work by allocating buffers and transforms.
+ */
+static int toi_compress_crypto_prepare(void)
+{
+        int cpu;
+
+        if (!*toi_compressor_name) {
+                printk(KERN_INFO "TuxOnIce: Compression enabled but no "
+                                "compressor name set.\n");
+                return 1;
+        }
+
+        for_each_online_cpu(cpu) {
+                struct cpu_context *this = &per_cpu(contexts, cpu);
+                this->transform = crypto_alloc_comp(toi_compressor_name, 0, 0);
+                if (IS_ERR(this->transform)) {
+                        printk(KERN_INFO "TuxOnIce: Failed to initialise the "
+                                        "%s compression transform.\n",
+                                        toi_compressor_name);
+                        this->transform = NULL;
+                        return 1;
+                }
+
+                this->page_buffer =
+                        (char *) toi_get_zeroed_page(16, TOI_ATOMIC_GFP);
+
+                if (!this->page_buffer) {
+                        printk(KERN_ERR
+                          "Failed to allocate a page buffer for TuxOnIce "
+                          "compression driver.\n");
+                        return -ENOMEM;
+                }
+
+                this->output_buffer =
+                        (char *) vmalloc_32(OUT_BUF_SIZE);
+
+                if (!this->output_buffer) {
+                        printk(KERN_ERR
+                          "Failed to allocate a output buffer for TuxOnIce "
+                          "compression driver.\n");
+                        return -ENOMEM;
+                }
+        }
+
+        return 0;
+}
+
+static int toi_compress_rw_cleanup(int writing)
+{
+        int cpu;
+
+        for_each_online_cpu(cpu) {
+                struct cpu_context *this = &per_cpu(contexts, cpu);
+                if (this->transform) {
+                        crypto_free_comp(this->transform);
+                        this->transform = NULL;
+                }
+
+                if (this->page_buffer)
+                        toi_free_page(16, (unsigned long) this->page_buffer);
+
+                this->page_buffer = NULL;
+
+                if (this->output_buffer)
+                        vfree(this->output_buffer);
+
+                this->output_buffer = NULL;
+        }
+
+        return 0;
+}
+
+/*
+ * toi_compress_init
+ */
+
+static int toi_compress_init(int toi_or_resume)
+{
+        if (!toi_or_resume)
+                return 0;
+
+        toi_compress_bytes_in = 0;
+        toi_compress_bytes_out = 0;
+
+        next_driver = toi_get_next_filter(&toi_compression_ops);
+
+        return next_driver ? 0 : -ECHILD;
+}
+
+/*
+ * toi_compress_rw_init()
+ */
+
+static int toi_compress_rw_init(int rw, int stream_number)
+{
+        if (toi_compress_crypto_prepare()) {
+                printk(KERN_ERR "Failed to initialise compression "
+                                "algorithm.\n");
+                if (rw == READ) {
+                        printk(KERN_INFO "Unable to read the image.\n");
+                        return -ENODEV;
+                } else {
+                        printk(KERN_INFO "Continuing without "
+                                "compressing the image.\n");
+                        toi_compression_ops.enabled = 0;
+                }
+        }
+
+        return 0;
+}
+
+/*
+ * toi_compress_write_page()
+ *
+ * Compress a page of data, buffering output and passing on filled
+ * pages to the next module in the pipeline.
+ *
+ * Buffer_page:        Pointer to a buffer of size PAGE_SIZE, containing
+ * data to be compressed.
+ *
+ * Returns:        0 on success. Otherwise the error is that returned by later
+ *                 modules, -ECHILD if we have a broken pipeline or -EIO if
+ *                 zlib errs.
+ */
+static int toi_compress_write_page(unsigned long index, int buf_type,
+                void *buffer_page, unsigned int buf_size)
+{
+        int ret = 0, cpu = smp_processor_id();
+        struct cpu_context *ctx = &per_cpu(contexts, cpu);
+        u8* output_buffer = buffer_page;
+        int output_len = buf_size;
+        int out_buf_type = buf_type;
+
+        if (ctx->transform) {
+
+                ctx->buffer_start = TOI_MAP(buf_type, buffer_page);
+                ctx->len = OUT_BUF_SIZE;
+
+                ret = crypto_comp_compress(ctx->transform,
+                        ctx->buffer_start, buf_size,
+                        ctx->output_buffer, &ctx->len);
+
+                TOI_UNMAP(buf_type, buffer_page);
+
+                toi_message(TOI_COMPRESS, TOI_VERBOSE, 0,
+                                "CPU %d, index %lu: %d bytes",
+                                cpu, index, ctx->len);
+
+                if (!ret && ctx->len < buf_size) { /* some compression */
+                        output_buffer = ctx->output_buffer;
+                        output_len = ctx->len;
+                        out_buf_type = TOI_VIRT;
+                }
+
+        }
+
+        mutex_lock(&stats_lock);
+
+        toi_compress_bytes_in += buf_size;
+        toi_compress_bytes_out += output_len;
+
+        mutex_unlock(&stats_lock);
+
+        if (!ret)
+                ret = next_driver->write_page(index, out_buf_type,
+                                output_buffer, output_len);
+
+        return ret;
+}
+
+/*
+ * toi_compress_read_page()
+ * @buffer_page: struct page *. Pointer to a buffer of size PAGE_SIZE.
+ *
+ * Retrieve data from later modules and decompress it until the input buffer
+ * is filled.
+ * Zero if successful. Error condition from me or from downstream on failure.
+ */
+static int toi_compress_read_page(unsigned long *index, int buf_type,
+                void *buffer_page, unsigned int *buf_size)
+{
+        int ret, cpu = smp_processor_id();
+        unsigned int len;
+        unsigned int outlen = PAGE_SIZE;
+        char *buffer_start;
+        struct cpu_context *ctx = &per_cpu(contexts, cpu);
+
+        if (!ctx->transform)
+                return next_driver->read_page(index, TOI_PAGE, buffer_page,
+                                buf_size);
+
+        /*
+         * All our reads must be synchronous - we can't decompress
+         * data that hasn't been read yet.
+         */
+
+        ret = next_driver->read_page(index, TOI_VIRT, ctx->page_buffer, &len);
+
+        buffer_start = kmap(buffer_page);
+
+        /* Error or uncompressed data */
+        if (ret || len == PAGE_SIZE) {
+                memcpy(buffer_start, ctx->page_buffer, len);
+                goto out;
+        }
+
+        ret = crypto_comp_decompress(
+                        ctx->transform,
+                        ctx->page_buffer,
+                        len, buffer_start, &outlen);
+
+        toi_message(TOI_COMPRESS, TOI_VERBOSE, 0,
+                        "CPU %d, index %lu: %d=>%d (%d).",
+                        cpu, *index, len, outlen, ret);
+
+        if (ret)
+                abort_hibernate(TOI_FAILED_IO,
+                        "Compress_read returned %d.\n", ret);
+        else if (outlen != PAGE_SIZE) {
+                abort_hibernate(TOI_FAILED_IO,
+                        "Decompression yielded %d bytes instead of %ld.\n",
+                        outlen, PAGE_SIZE);
+                printk(KERN_ERR "Decompression yielded %d bytes instead of "
+                                "%ld.\n", outlen, PAGE_SIZE);
+                ret = -EIO;
+                *buf_size = outlen;
+        }
+out:
+        TOI_UNMAP(buf_type, buffer_page);
+        return ret;
+}
+
+/*
+ * toi_compress_print_debug_stats
+ * @buffer: Pointer to a buffer into which the debug info will be printed.
+ * @size: Size of the buffer.
+ *
+ * Print information to be recorded for debugging purposes into a buffer.
+ * Returns: Number of characters written to the buffer.
+ */
+
+static int toi_compress_print_debug_stats(char *buffer, int size)
+{
+        unsigned long pages_in = toi_compress_bytes_in >> PAGE_SHIFT,
+                      pages_out = toi_compress_bytes_out >> PAGE_SHIFT;
+        int len;
+
+        /* Output the compression ratio achieved. */
+        if (*toi_compressor_name)
+                len = scnprintf(buffer, size, "- Compressor is '%s'.\n",
+                                toi_compressor_name);
+        else
+                len = scnprintf(buffer, size, "- Compressor is not set.\n");
+
+        if (pages_in)
+                len += scnprintf(buffer+len, size - len, "  Compressed "
+                        "%lu bytes into %lu (%ld percent compression).\n",
+                  toi_compress_bytes_in,
+                  toi_compress_bytes_out,
+                  (pages_in - pages_out) * 100 / pages_in);
+        return len;
+}
+
+/*
+ * toi_compress_compression_memory_needed
+ *
+ * Tell the caller how much memory we need to operate during hibernate/resume.
+ * Returns: Unsigned long. Maximum number of bytes of memory required for
+ * operation.
+ */
+static int toi_compress_memory_needed(void)
+{
+        return 2 * PAGE_SIZE;
+}
+
+static int toi_compress_storage_needed(void)
+{
+        return 2 * sizeof(unsigned long) + 2 * sizeof(int) +
+                strlen(toi_compressor_name) + 1;
+}
+
+/*
+ * toi_compress_save_config_info
+ * @buffer: Pointer to a buffer of size PAGE_SIZE.
+ *
+ * Save informaton needed when reloading the image at resume time.
+ * Returns: Number of bytes used for saving our data.
+ */
+static int toi_compress_save_config_info(char *buffer)
+{
+        int len = strlen(toi_compressor_name) + 1, offset = 0;
+
+        *((unsigned long *) buffer) = toi_compress_bytes_in;
+        offset += sizeof(unsigned long);
+        *((unsigned long *) (buffer + offset)) = toi_compress_bytes_out;
+        offset += sizeof(unsigned long);
+        *((int *) (buffer + offset)) = toi_expected_compression;
+        offset += sizeof(int);
+        *((int *) (buffer + offset)) = len;
+        offset += sizeof(int);
+        strncpy(buffer + offset, toi_compressor_name, len);
+        return offset + len;
+}
+
+/* toi_compress_load_config_info
+ * @buffer: Pointer to the start of the data.
+ * @size: Number of bytes that were saved.
+ *
+ * Description:        Reload information needed for decompressing the image at
+ * resume time.
+ */
+static void toi_compress_load_config_info(char *buffer, int size)
+{
+        int len, offset = 0;
+
+        toi_compress_bytes_in = *((unsigned long *) buffer);
+        offset += sizeof(unsigned long);
+        toi_compress_bytes_out = *((unsigned long *) (buffer + offset));
+        offset += sizeof(unsigned long);
+        toi_expected_compression = *((int *) (buffer + offset));
+        offset += sizeof(int);
+        len = *((int *) (buffer + offset));
+        offset += sizeof(int);
+        strncpy(toi_compressor_name, buffer + offset, len);
+}
+
+static void toi_compress_pre_atomic_restore(struct toi_boot_kernel_data *bkd)
+{
+        bkd->compress_bytes_in = toi_compress_bytes_in;
+        bkd->compress_bytes_out = toi_compress_bytes_out;
+}
+
+static void toi_compress_post_atomic_restore(struct toi_boot_kernel_data *bkd)
+{
+        toi_compress_bytes_in = bkd->compress_bytes_in;
+        toi_compress_bytes_out = bkd->compress_bytes_out;
+}
+
+/*
+ * toi_expected_compression_ratio
+ *
+ * Description:        Returns the expected ratio between data passed into this module
+ *                 and the amount of data output when writing.
+ * Returns:        100 if the module is disabled. Otherwise the value set by the
+ *                 user via our sysfs entry.
+ */
+
+static int toi_compress_expected_ratio(void)
+{
+        if (!toi_compression_ops.enabled)
+                return 100;
+        else
+                return 100 - toi_expected_compression;
+}
+
+/*
+ * data for our sysfs entries.
+ */
+static struct toi_sysfs_data sysfs_params[] = {
+        SYSFS_INT("expected_compression", SYSFS_RW, &toi_expected_compression,
+                        0, 99, 0, NULL),
+        SYSFS_INT("enabled", SYSFS_RW, &toi_compression_ops.enabled, 0, 1, 0,
+                        NULL),
+        SYSFS_STRING("algorithm", SYSFS_RW, toi_compressor_name, 31, 0, NULL),
+};
+
+/*
+ * Ops structure.
+ */
+static struct toi_module_ops toi_compression_ops = {
+        .type                        = FILTER_MODULE,
+        .name                        = "compression",
+        .directory                = "compression",
+        .module                        = THIS_MODULE,
+        .initialise                = toi_compress_init,
+        .memory_needed                 = toi_compress_memory_needed,
+        .print_debug_info        = toi_compress_print_debug_stats,
+        .save_config_info        = toi_compress_save_config_info,
+        .load_config_info        = toi_compress_load_config_info,
+        .storage_needed                = toi_compress_storage_needed,
+        .expected_compression        = toi_compress_expected_ratio,
+
+        .pre_atomic_restore        = toi_compress_pre_atomic_restore,
+        .post_atomic_restore        = toi_compress_post_atomic_restore,
+
+        .rw_init                = toi_compress_rw_init,
+        .rw_cleanup                = toi_compress_rw_cleanup,
+
+        .write_page                = toi_compress_write_page,
+        .read_page                = toi_compress_read_page,
+
+        .sysfs_data                = sysfs_params,
+        .num_sysfs_entries        = sizeof(sysfs_params) /
+                sizeof(struct toi_sysfs_data),
+};
+
+/* ---- Registration ---- */
+
+static __init int toi_compress_load(void)
+{
+        return toi_register_module(&toi_compression_ops);
+}
+
+late_initcall(toi_compress_load);
diff --git a/kernel/power/tuxonice_copy_before_write.c b/kernel/power/tuxonice_copy_before_write.c
new file mode 100644
index 000000000..eb627915e
--- /dev/null
+++ b/kernel/power/tuxonice_copy_before_write.c
@@ -0,0 +1,240 @@
+/*
+ * kernel/power/tuxonice_copy_before_write.c
+ *
+ * Copyright (C) 2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * Routines (apart from the fault handling code) to deal with allocating memory
+ * for copying pages before they are modified, restoring the contents and getting
+ * the contents written to disk.
+ */
+
+#include <linux/percpu-defs.h>
+#include <linux/sched.h>
+#include <linux/tuxonice.h>
+#include "tuxonice_alloc.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice.h"
+
+DEFINE_PER_CPU(struct toi_cbw_state, toi_cbw_states);
+#define CBWS_PER_PAGE (PAGE_SIZE / sizeof(struct toi_cbw))
+#define toi_cbw_pool_size 100
+
+static void _toi_free_cbw_data(struct toi_cbw_state *state)
+{
+    struct toi_cbw *page_ptr, *ptr, *next;
+
+    page_ptr = ptr = state->first;
+
+    while(ptr) {
+        next = ptr->next;
+
+        if (ptr->virt) {
+            toi__free_page(40, virt_to_page(ptr->virt));
+        }
+        if ((((unsigned long) ptr) & PAGE_MASK) != (unsigned long) page_ptr) {
+            /* Must be on a new page - free the previous one. */
+            toi__free_page(40, virt_to_page(page_ptr));
+            page_ptr = ptr;
+        }
+        ptr = next;
+    }
+
+    if (page_ptr) {
+        toi__free_page(40, virt_to_page(page_ptr));
+    }
+
+    state->first = state->next = state->last = NULL;
+    state->size = 0;
+}
+
+void toi_free_cbw_data(void)
+{
+    int i;
+
+    for_each_online_cpu(i) {
+        struct toi_cbw_state *state = &per_cpu(toi_cbw_states, i);
+
+        if (!state->first)
+            continue;
+
+        state->enabled = 0;
+
+        while (state->active) {
+            schedule();
+        }
+
+        _toi_free_cbw_data(state);
+    }
+}
+
+static int _toi_allocate_cbw_data(struct toi_cbw_state *state)
+{
+    while(state->size < toi_cbw_pool_size) {
+        int i;
+        struct toi_cbw *ptr;
+
+        ptr = (struct toi_cbw *) toi_get_zeroed_page(40, GFP_KERNEL);
+
+        if (!ptr) {
+            return -ENOMEM;
+        }
+
+        if (!state->first) {
+            state->first = state->next = state->last = ptr;
+        }
+
+        for (i = 0; i < CBWS_PER_PAGE; i++) {
+            struct toi_cbw *cbw = &ptr[i];
+
+            cbw->virt = (char *) toi_get_zeroed_page(40, GFP_KERNEL);
+            if (!cbw->virt) {
+                state->size += i;
+                printk("Out of memory allocating CBW pages.\n");
+                return -ENOMEM;
+            }
+
+            if (cbw == state->first)
+                continue;
+
+            state->last->next = cbw;
+            state->last = cbw;
+        }
+
+        state->size += CBWS_PER_PAGE;
+    }
+
+    state->enabled = 1;
+
+    return 0;
+}
+
+
+int toi_allocate_cbw_data(void)
+{
+    int i, result;
+
+    for_each_online_cpu(i) {
+        struct toi_cbw_state *state = &per_cpu(toi_cbw_states, i);
+
+        result = _toi_allocate_cbw_data(state);
+
+        if (result)
+            return result;
+    }
+
+    return 0;
+}
+
+void toi_cbw_restore(void)
+{
+    if (!toi_keeping_image)
+        return;
+
+}
+
+void toi_cbw_write(void)
+{
+    if (!toi_keeping_image)
+        return;
+
+}
+
+/**
+ * toi_cbw_test_read - Test copy before write on one page
+ *
+ * Allocate copy before write buffers, then make one page only copy-before-write
+ * and attempt to write to it. We should then be able to retrieve the original
+ * version from the cbw buffer and the modified version from the page itself.
+ */
+static int toi_cbw_test_read(const char *buffer, int count)
+{
+    unsigned long virt = toi_get_zeroed_page(40, GFP_KERNEL);
+    char *original = "Original contents";
+    char *modified = "Modified material";
+    struct page *page = virt_to_page(virt);
+    int i, len = 0, found = 0, pfn = page_to_pfn(page);
+
+    if (!page) {
+        printk("toi_cbw_test_read: Unable to allocate a page for testing.\n");
+        return -ENOMEM;
+    }
+
+    memcpy((char *) virt, original, strlen(original));
+
+    if (toi_allocate_cbw_data()) {
+        printk("toi_cbw_test_read: Unable to allocate cbw data.\n");
+        return -ENOMEM;
+    }
+
+    toi_reset_dirtiness_one(pfn, 0);
+
+    SetPageTOI_CBW(page);
+
+    memcpy((char *) virt, modified, strlen(modified));
+
+    if (strncmp((char *) virt, modified, strlen(modified))) {
+        len += sprintf((char *) buffer + len, "Failed to write to page after protecting it.\n");
+    }
+
+    for_each_online_cpu(i) {
+        struct toi_cbw_state *state = &per_cpu(toi_cbw_states, i);
+        struct toi_cbw *ptr = state->first, *last_ptr = ptr;
+
+        if (!found) {
+            while (ptr) {
+                if (ptr->pfn == pfn) {
+                    found = 1;
+                    if (strncmp(ptr->virt, original, strlen(original))) {
+                        len += sprintf((char *) buffer + len, "Contents of original buffer are not original.\n");
+                    } else {
+                        len += sprintf((char *) buffer + len, "Test passed. Buffer changed and original contents preserved.\n");
+                    }
+                    break;
+                }
+
+                last_ptr = ptr;
+                ptr = ptr->next;
+            }
+        }
+
+        if (!last_ptr)
+            len += sprintf((char *) buffer + len, "All available CBW buffers on cpu %d used.\n", i);
+    }
+
+    if (!found)
+        len += sprintf((char *) buffer + len, "Copy before write buffer not found.\n");
+
+    toi_free_cbw_data();
+
+    return len;
+}
+
+/*
+ * This array contains entries that are automatically registered at
+ * boot. Modules and the console code register their own entries separately.
+ */
+static struct toi_sysfs_data sysfs_params[] = {
+        SYSFS_CUSTOM("test", SYSFS_RW, toi_cbw_test_read,
+                        NULL, SYSFS_NEEDS_SM_FOR_READ, NULL),
+};
+
+static struct toi_module_ops toi_cbw_ops = {
+        .type                                        = MISC_HIDDEN_MODULE,
+        .name                                        = "copy_before_write debugging",
+        .directory                                = "cbw",
+        .module                                        = THIS_MODULE,
+        .early                                        = 1,
+
+        .sysfs_data                = sysfs_params,
+        .num_sysfs_entries        = sizeof(sysfs_params) /
+                sizeof(struct toi_sysfs_data),
+};
+
+int toi_cbw_init(void)
+{
+        int result = toi_register_module(&toi_cbw_ops);
+        return result;
+}
diff --git a/kernel/power/tuxonice_extent.c b/kernel/power/tuxonice_extent.c
new file mode 100644
index 000000000..522c836ad
--- /dev/null
+++ b/kernel/power/tuxonice_extent.c
@@ -0,0 +1,144 @@
+/*
+ * kernel/power/tuxonice_extent.c
+ *
+ * Copyright (C) 2003-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * Distributed under GPLv2.
+ *
+ * These functions encapsulate the manipulation of storage metadata.
+ */
+
+#include <linux/suspend.h>
+#include "tuxonice_modules.h"
+#include "tuxonice_extent.h"
+#include "tuxonice_alloc.h"
+#include "tuxonice_ui.h"
+#include "tuxonice.h"
+
+/**
+ * toi_get_extent - return a free extent
+ *
+ * May fail, returning NULL instead.
+ **/
+static struct hibernate_extent *toi_get_extent(void)
+{
+        return (struct hibernate_extent *) toi_kzalloc(2,
+                        sizeof(struct hibernate_extent), TOI_ATOMIC_GFP);
+}
+
+/**
+ * toi_put_extent_chain - free a chain of extents starting from value 'from'
+ * @chain:        Chain to free.
+ *
+ * Note that 'from' is an extent value, and may be part way through an extent.
+ * In this case, the extent should be truncated (if necessary) and following
+ * extents freed.
+ **/
+void toi_put_extent_chain_from(struct hibernate_extent_chain *chain, unsigned long from)
+{
+        struct hibernate_extent *this;
+
+        this = chain->first;
+
+        while (this) {
+                struct hibernate_extent *next = this->next;
+
+                // Delete the whole extent?
+                if (this->start >= from) {
+                    chain->size -= (this->end - this->start + 1);
+                    if (chain->first == this)
+                        chain->first = next;
+                    if (chain->last_touched == this)
+                        chain->last_touched = NULL;
+                    if (chain->current_extent == this)
+                        chain->current_extent = NULL;
+                    toi_kfree(2, this, sizeof(*this));
+                    chain->num_extents--;
+                } else if (this->end >= from) {
+                    // Delete part of the extent
+                    chain->size -= (this->end - from + 1);
+                    this->start = from;
+                }
+                this = next;
+        }
+}
+
+/**
+ * toi_put_extent_chain - free a whole chain of extents
+ * @chain:        Chain to free.
+ **/
+void toi_put_extent_chain(struct hibernate_extent_chain *chain)
+{
+    toi_put_extent_chain_from(chain, 0);
+}
+
+/**
+ * toi_add_to_extent_chain - add an extent to an existing chain
+ * @chain:        Chain to which the extend should be added
+ * @start:        Start of the extent (first physical block)
+ * @end:        End of the extent (last physical block)
+ *
+ * The chain information is updated if the insertion is successful.
+ **/
+int toi_add_to_extent_chain(struct hibernate_extent_chain *chain,
+                unsigned long start, unsigned long end)
+{
+        struct hibernate_extent *new_ext = NULL, *cur_ext = NULL;
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0,
+                "Adding extent %lu-%lu to chain %p.\n", start, end, chain);
+
+        /* Find the right place in the chain */
+        if (chain->last_touched && chain->last_touched->start < start)
+                cur_ext = chain->last_touched;
+        else if (chain->first && chain->first->start < start)
+                cur_ext = chain->first;
+
+        if (cur_ext) {
+                while (cur_ext->next && cur_ext->next->start < start)
+                        cur_ext = cur_ext->next;
+
+                if (cur_ext->end == (start - 1)) {
+                        struct hibernate_extent *next_ext = cur_ext->next;
+                        cur_ext->end = end;
+
+                        /* Merge with the following one? */
+                        if (next_ext && cur_ext->end + 1 == next_ext->start) {
+                                cur_ext->end = next_ext->end;
+                                cur_ext->next = next_ext->next;
+                                toi_kfree(2, next_ext, sizeof(*next_ext));
+                                chain->num_extents--;
+                        }
+
+                        chain->last_touched = cur_ext;
+                        chain->size += (end - start + 1);
+
+                        return 0;
+                }
+        }
+
+        new_ext = toi_get_extent();
+        if (!new_ext) {
+                printk(KERN_INFO "Error unable to append a new extent to the "
+                                "chain.\n");
+                return -ENOMEM;
+        }
+
+        chain->num_extents++;
+        chain->size += (end - start + 1);
+        new_ext->start = start;
+        new_ext->end = end;
+
+        chain->last_touched = new_ext;
+
+        if (cur_ext) {
+                new_ext->next = cur_ext->next;
+                cur_ext->next = new_ext;
+        } else {
+                if (chain->first)
+                        new_ext->next = chain->first;
+                chain->first = new_ext;
+        }
+
+        return 0;
+}
diff --git a/kernel/power/tuxonice_extent.h b/kernel/power/tuxonice_extent.h
new file mode 100644
index 000000000..aeccf1f5e
--- /dev/null
+++ b/kernel/power/tuxonice_extent.h
@@ -0,0 +1,45 @@
+/*
+ * kernel/power/tuxonice_extent.h
+ *
+ * Copyright (C) 2003-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * It contains declarations related to extents. Extents are
+ * TuxOnIce's method of storing some of the metadata for the image.
+ * See tuxonice_extent.c for more info.
+ *
+ */
+
+#include "tuxonice_modules.h"
+
+#ifndef EXTENT_H
+#define EXTENT_H
+
+struct hibernate_extent {
+        unsigned long start, end;
+        struct hibernate_extent *next;
+};
+
+struct hibernate_extent_chain {
+        unsigned long size; /* size of the chain ie sum (max-min+1) */
+        int num_extents;
+        struct hibernate_extent *first, *last_touched;
+        struct hibernate_extent *current_extent;
+        unsigned long current_offset;
+};
+
+/* Simplify iterating through all the values in an extent chain */
+#define toi_extent_for_each(extent_chain, extentpointer, value) \
+if ((extent_chain)->first) \
+        for ((extentpointer) = (extent_chain)->first, (value) = \
+                        (extentpointer)->start; \
+             ((extentpointer) && ((extentpointer)->next || (value) <= \
+                                 (extentpointer)->end)); \
+             (((value) == (extentpointer)->end) ? \
+                ((extentpointer) = (extentpointer)->next, (value) = \
+                 ((extentpointer) ? (extentpointer)->start : 0)) : \
+                        (value)++))
+
+extern void toi_put_extent_chain_from(struct hibernate_extent_chain *chain, unsigned long from);
+#endif
diff --git a/kernel/power/tuxonice_file.c b/kernel/power/tuxonice_file.c
new file mode 100644
index 000000000..baf191211
--- /dev/null
+++ b/kernel/power/tuxonice_file.c
@@ -0,0 +1,484 @@
+/*
+ * kernel/power/tuxonice_file.c
+ *
+ * Copyright (C) 2005-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * Distributed under GPLv2.
+ *
+ * This file encapsulates functions for usage of a simple file as a
+ * backing store. It is based upon the swapallocator, and shares the
+ * same basic working. Here, though, we have nothing to do with
+ * swapspace, and only one device to worry about.
+ *
+ * The user can just
+ *
+ * echo TuxOnIce > /path/to/my_file
+ *
+ * dd if=/dev/zero bs=1M count=<file_size_desired> >> /path/to/my_file
+ *
+ * and
+ *
+ * echo /path/to/my_file > /sys/power/tuxonice/file/target
+ *
+ * then put what they find in /sys/power/tuxonice/resume
+ * as their resume= parameter in lilo.conf (and rerun lilo if using it).
+ *
+ * Having done this, they're ready to hibernate and resume.
+ *
+ * TODO:
+ * - File resizing.
+ */
+
+#include <linux/blkdev.h>
+#include <linux/mount.h>
+#include <linux/fs.h>
+#include <linux/fs_uuid.h>
+
+#include "tuxonice.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_bio.h"
+#include "tuxonice_alloc.h"
+#include "tuxonice_builtin.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_io.h"
+
+#define target_is_normal_file() (S_ISREG(target_inode->i_mode))
+
+static struct toi_module_ops toi_fileops;
+
+static struct file *target_file;
+static struct block_device *toi_file_target_bdev;
+static unsigned long pages_available, pages_allocated;
+static char toi_file_target[256];
+static struct inode *target_inode;
+static int file_target_priority;
+static int used_devt;
+static int target_claim;
+static dev_t toi_file_dev_t;
+static int sig_page_index;
+
+/* For test_toi_file_target */
+static struct toi_bdev_info *file_chain;
+
+static int has_contiguous_blocks(struct toi_bdev_info *dev_info, int page_num)
+{
+        int j;
+        sector_t last = 0;
+
+        for (j = 0; j < dev_info->blocks_per_page; j++) {
+                sector_t this = bmap(target_inode,
+                                page_num * dev_info->blocks_per_page + j);
+
+                if (!this || (last && (last + 1) != this))
+                        break;
+
+                last = this;
+        }
+
+        return j == dev_info->blocks_per_page;
+}
+
+static unsigned long get_usable_pages(struct toi_bdev_info *dev_info)
+{
+        unsigned long result = 0;
+        struct block_device *bdev = dev_info->bdev;
+        int i;
+
+        switch (target_inode->i_mode & S_IFMT) {
+        case S_IFSOCK:
+        case S_IFCHR:
+        case S_IFIFO: /* Socket, Char, Fifo */
+                return -1;
+        case S_IFREG: /* Regular file: current size - holes + free
+                         space on part */
+                for (i = 0; i < (target_inode->i_size >> PAGE_SHIFT) ; i++) {
+                        if (has_contiguous_blocks(dev_info, i))
+                                result++;
+                }
+                break;
+        case S_IFBLK: /* Block device */
+                if (!bdev->bd_disk) {
+                        toi_message(TOI_IO, TOI_VERBOSE, 0,
+                                        "bdev->bd_disk null.");
+                        return 0;
+                }
+
+                result = (bdev->bd_part ?
+                        bdev->bd_part->nr_sects :
+                        get_capacity(bdev->bd_disk)) >> (PAGE_SHIFT - 9);
+        }
+
+
+        return result;
+}
+
+static int toi_file_register_storage(void)
+{
+        struct toi_bdev_info *devinfo;
+        int result = 0;
+        struct fs_info *fs_info;
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "toi_file_register_storage.");
+        if (!strlen(toi_file_target)) {
+                toi_message(TOI_IO, TOI_VERBOSE, 0, "Register file storage: "
+                                "No target filename set.");
+                return 0;
+        }
+
+        target_file = filp_open(toi_file_target, O_RDONLY|O_LARGEFILE, 0);
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "filp_open %s returned %p.",
+                        toi_file_target, target_file);
+
+        if (IS_ERR(target_file) || !target_file) {
+                target_file = NULL;
+                toi_file_dev_t = name_to_dev_t(toi_file_target);
+                if (!toi_file_dev_t) {
+                        struct kstat stat;
+                        int error = vfs_stat(toi_file_target, &stat);
+                        printk(KERN_INFO "Open file %s returned %p and "
+                                        "name_to_devt failed.\n",
+                                        toi_file_target, target_file);
+                        if (error) {
+                                printk(KERN_INFO "Stating the file also failed."
+                                        " Nothing more we can do.\n");
+                                return 0;
+                        } else
+                                toi_file_dev_t = stat.rdev;
+                }
+
+                toi_file_target_bdev = toi_open_by_devnum(toi_file_dev_t);
+                if (IS_ERR(toi_file_target_bdev)) {
+                        printk(KERN_INFO "Got a dev_num (%lx) but failed to "
+                                        "open it.\n",
+                                        (unsigned long) toi_file_dev_t);
+                        toi_file_target_bdev = NULL;
+                        return 0;
+                }
+                used_devt = 1;
+                target_inode = toi_file_target_bdev->bd_inode;
+        } else
+                target_inode = target_file->f_mapping->host;
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "Succeeded in opening the target.");
+        if (S_ISLNK(target_inode->i_mode) || S_ISDIR(target_inode->i_mode) ||
+            S_ISSOCK(target_inode->i_mode) || S_ISFIFO(target_inode->i_mode)) {
+                printk(KERN_INFO "File support works with regular files,"
+                                " character files and block devices.\n");
+                /* Cleanup routine will undo the above */
+                return 0;
+        }
+
+        if (!used_devt) {
+                if (S_ISBLK(target_inode->i_mode)) {
+                        toi_file_target_bdev = I_BDEV(target_inode);
+                        if (!blkdev_get(toi_file_target_bdev, FMODE_WRITE |
+                                                FMODE_READ, NULL))
+                                target_claim = 1;
+                } else
+                        toi_file_target_bdev = target_inode->i_sb->s_bdev;
+                if (!toi_file_target_bdev) {
+                        printk(KERN_INFO "%s is not a valid file allocator "
+                                        "target.\n", toi_file_target);
+                        return 0;
+                }
+                toi_file_dev_t = toi_file_target_bdev->bd_dev;
+        }
+
+        devinfo = toi_kzalloc(39, sizeof(struct toi_bdev_info), GFP_ATOMIC);
+        if (!devinfo) {
+                printk("Failed to allocate a toi_bdev_info struct for the file allocator.\n");
+                return -ENOMEM;
+        }
+
+        devinfo->bdev = toi_file_target_bdev;
+        devinfo->allocator = &toi_fileops;
+        devinfo->allocator_index = 0;
+
+        fs_info = fs_info_from_block_dev(toi_file_target_bdev);
+        if (fs_info && !IS_ERR(fs_info)) {
+                memcpy(devinfo->uuid, &fs_info->uuid, 16);
+                free_fs_info(fs_info);
+        } else
+                result = (int) PTR_ERR(fs_info);
+
+        /* Unlike swap code, only complain if fs_info_from_block_dev returned
+         * -ENOMEM. The 'file' might be a full partition, so might validly not
+         * have an identifiable type, UUID etc.
+         */
+        if (result)
+                printk(KERN_DEBUG "Failed to get fs_info for file device (%d).\n",
+                                result);
+        devinfo->dev_t = toi_file_dev_t;
+        devinfo->prio = file_target_priority;
+        devinfo->bmap_shift = target_inode->i_blkbits - 9;
+        devinfo->blocks_per_page =
+                (1 << (PAGE_SHIFT - target_inode->i_blkbits));
+        sprintf(devinfo->name, "file %s", toi_file_target);
+        file_chain = devinfo;
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "Dev_t is %lx. Prio is %d. Bmap "
+                        "shift is %d. Blocks per page %d.",
+                        devinfo->dev_t, devinfo->prio, devinfo->bmap_shift,
+                        devinfo->blocks_per_page);
+
+        /* Keep one aside for the signature */
+        pages_available = get_usable_pages(devinfo) - 1;
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "Registering file storage, %lu "
+                        "pages.", pages_available);
+
+        toi_bio_ops.register_storage(devinfo);
+        return 0;
+}
+
+static unsigned long toi_file_storage_available(void)
+{
+        return pages_available;
+}
+
+static int toi_file_allocate_storage(struct toi_bdev_info *chain,
+                unsigned long request)
+{
+        unsigned long available = pages_available - pages_allocated;
+        unsigned long to_add = min(available, request);
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "Pages available is %lu. Allocated "
+                "is %lu. Allocating %lu pages from file.",
+                pages_available, pages_allocated, to_add);
+        pages_allocated += to_add;
+
+        return to_add;
+}
+
+/**
+ * __populate_block_list - add an extent to the chain
+ * @min:        Start of the extent (first physical block = sector)
+ * @max:        End of the extent (last physical block = sector)
+ *
+ * If TOI_TEST_BIO is set, print a debug message, outputting the min and max
+ * fs block numbers.
+ **/
+static int __populate_block_list(struct toi_bdev_info *chain, int min, int max)
+{
+        if (test_action_state(TOI_TEST_BIO))
+                toi_message(TOI_IO, TOI_VERBOSE, 0, "Adding extent %d-%d.",
+                        min << chain->bmap_shift,
+                        ((max + 1) << chain->bmap_shift) - 1);
+
+        return toi_add_to_extent_chain(&chain->blocks, min, max);
+}
+
+static int get_main_pool_phys_params(struct toi_bdev_info *chain)
+{
+        int i, extent_min = -1, extent_max = -1, result = 0, have_sig_page = 0;
+        unsigned long pages_mapped = 0;
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "Getting file allocator blocks.");
+
+        if (chain->blocks.first)
+                toi_put_extent_chain(&chain->blocks);
+
+        if (!target_is_normal_file()) {
+                result = (pages_available > 0) ?
+                        __populate_block_list(chain, chain->blocks_per_page,
+                                (pages_allocated + 1) *
+                                chain->blocks_per_page - 1) : 0;
+                return result;
+        }
+
+        /*
+         * FIXME: We are assuming the first page is contiguous. Is that
+         * assumption always right?
+         */
+
+        for (i = 0; i < (target_inode->i_size >> PAGE_SHIFT); i++) {
+                sector_t new_sector;
+
+                if (!has_contiguous_blocks(chain, i))
+                        continue;
+
+                if (!have_sig_page) {
+                        have_sig_page = 1;
+                        sig_page_index = i;
+                        continue;
+                }
+
+                pages_mapped++;
+
+                /* Ignore first page - it has the header */
+                if (pages_mapped == 1)
+                        continue;
+
+                new_sector = bmap(target_inode, (i * chain->blocks_per_page));
+
+                /*
+                 * I'd love to be able to fill in holes and resize
+                 * files, but not yet...
+                 */
+
+                if (new_sector == extent_max + 1)
+                        extent_max += chain->blocks_per_page;
+                else {
+                        if (extent_min > -1) {
+                                result = __populate_block_list(chain,
+                                                extent_min, extent_max);
+                                if (result)
+                                        return result;
+                        }
+
+                        extent_min = new_sector;
+                        extent_max = extent_min +
+                                chain->blocks_per_page - 1;
+                }
+
+                if (pages_mapped == pages_allocated)
+                        break;
+        }
+
+        if (extent_min > -1) {
+                result = __populate_block_list(chain, extent_min, extent_max);
+                if (result)
+                        return result;
+        }
+
+        return 0;
+}
+
+static void toi_file_free_storage(struct toi_bdev_info *chain)
+{
+        pages_allocated = 0;
+        file_chain = NULL;
+}
+
+/**
+ * toi_file_print_debug_stats - print debug info
+ * @buffer:        Buffer to data to populate
+ * @size:        Size of the buffer
+ **/
+static int toi_file_print_debug_stats(char *buffer, int size)
+{
+        int len = scnprintf(buffer, size, "- File Allocator active.\n");
+
+        len += scnprintf(buffer+len, size-len, "  Storage available for "
+                        "image: %lu pages.\n", pages_available);
+
+        return len;
+}
+
+static void toi_file_cleanup(int finishing_cycle)
+{
+        if (toi_file_target_bdev) {
+                if (target_claim) {
+                        blkdev_put(toi_file_target_bdev, FMODE_WRITE | FMODE_READ);
+                        target_claim = 0;
+                }
+
+                if (used_devt) {
+                        blkdev_put(toi_file_target_bdev,
+                                        FMODE_READ | FMODE_NDELAY);
+                        used_devt = 0;
+                }
+                toi_file_target_bdev = NULL;
+                target_inode = NULL;
+        }
+
+        if (target_file) {
+                filp_close(target_file, NULL);
+                target_file = NULL;
+        }
+
+        pages_available = 0;
+}
+
+/**
+ * test_toi_file_target - sysfs callback for /sys/power/tuxonince/file/target
+ *
+ * Test wheter the target file is valid for hibernating.
+ **/
+static void test_toi_file_target(void)
+{
+        int result = toi_file_register_storage();
+        sector_t sector;
+        char buf[50];
+        struct fs_info *fs_info;
+
+        if (result || !file_chain)
+                return;
+
+        /* This doesn't mean we're in business. Is any storage available? */
+        if (!pages_available)
+                goto out;
+
+        toi_file_allocate_storage(file_chain, 1);
+        result = get_main_pool_phys_params(file_chain);
+        if (result)
+                goto out;
+
+
+        sector = bmap(target_inode, sig_page_index *
+                        file_chain->blocks_per_page) << file_chain->bmap_shift;
+
+        /* Use the uuid, or the dev_t if that fails */
+        fs_info = fs_info_from_block_dev(toi_file_target_bdev);
+        if (!fs_info || IS_ERR(fs_info)) {
+                bdevname(toi_file_target_bdev, buf);
+                sprintf(resume_file, "/dev/%s:%llu", buf,
+                                (unsigned long long) sector);
+        } else {
+                int i;
+                hex_dump_to_buffer(fs_info->uuid, 16, 32, 1, buf, 50, 0);
+
+                /* Remove the spaces */
+                for (i = 1; i < 16; i++) {
+                        buf[2 * i] = buf[3 * i];
+                        buf[2 * i + 1] = buf[3 * i + 1];
+                }
+                buf[32] = 0;
+                sprintf(resume_file, "UUID=%s:0x%llx", buf,
+                                (unsigned long long) sector);
+                free_fs_info(fs_info);
+        }
+
+        toi_attempt_to_parse_resume_device(0);
+out:
+        toi_file_free_storage(file_chain);
+        toi_bio_ops.free_storage();
+}
+
+static struct toi_sysfs_data sysfs_params[] = {
+        SYSFS_STRING("target", SYSFS_RW, toi_file_target, 256,
+                SYSFS_NEEDS_SM_FOR_WRITE, test_toi_file_target),
+        SYSFS_INT("enabled", SYSFS_RW, &toi_fileops.enabled, 0, 1, 0, NULL),
+        SYSFS_INT("priority", SYSFS_RW, &file_target_priority, -4095,
+                        4096, 0, NULL),
+};
+
+static struct toi_bio_allocator_ops toi_bio_fileops = {
+        .register_storage                        = toi_file_register_storage,
+        .storage_available                        = toi_file_storage_available,
+        .allocate_storage                        = toi_file_allocate_storage,
+        .bmap                                        = get_main_pool_phys_params,
+        .free_storage                                = toi_file_free_storage,
+};
+
+static struct toi_module_ops toi_fileops = {
+        .type                                        = BIO_ALLOCATOR_MODULE,
+        .name                                        = "file storage",
+        .directory                                = "file",
+        .module                                        = THIS_MODULE,
+        .print_debug_info                        = toi_file_print_debug_stats,
+        .cleanup                                = toi_file_cleanup,
+        .bio_allocator_ops                        = &toi_bio_fileops,
+
+        .sysfs_data                = sysfs_params,
+        .num_sysfs_entries        = sizeof(sysfs_params) /
+                sizeof(struct toi_sysfs_data),
+};
+
+/* ---- Registration ---- */
+static __init int toi_file_load(void)
+{
+        return toi_register_module(&toi_fileops);
+}
+
+late_initcall(toi_file_load);
diff --git a/kernel/power/tuxonice_highlevel.c b/kernel/power/tuxonice_highlevel.c
new file mode 100644
index 000000000..16cf14cbc
--- /dev/null
+++ b/kernel/power/tuxonice_highlevel.c
@@ -0,0 +1,1413 @@
+/*
+ * kernel/power/tuxonice_highlevel.c
+ */
+/** \mainpage TuxOnIce.
+ *
+ * TuxOnIce provides support for saving and restoring an image of
+ * system memory to an arbitrary storage device, either on the local computer,
+ * or across some network. The support is entirely OS based, so TuxOnIce
+ * works without requiring BIOS, APM or ACPI support. The vast majority of the
+ * code is also architecture independant, so it should be very easy to port
+ * the code to new architectures. TuxOnIce includes support for SMP, 4G HighMem
+ * and preemption. Initramfses and initrds are also supported.
+ *
+ * TuxOnIce uses a modular design, in which the method of storing the image is
+ * completely abstracted from the core code, as are transformations on the data
+ * such as compression and/or encryption (multiple 'modules' can be used to
+ * provide arbitrary combinations of functionality). The user interface is also
+ * modular, so that arbitrarily simple or complex interfaces can be used to
+ * provide anything from debugging information through to eye candy.
+ *
+ * \section Copyright
+ *
+ * TuxOnIce is released under the GPLv2.
+ *
+ * Copyright (C) 1998-2001 Gabor Kuti <seasons@fornax.hu><BR>
+ * Copyright (C) 1998,2001,2002 Pavel Machek <pavel@suse.cz><BR>
+ * Copyright (C) 2002-2003 Florent Chabaud <fchabaud@free.fr><BR>
+ * Copyright (C) 2002-2015 Nigel Cunningham (nigel at nigelcunningham com au)<BR>
+ *
+ * \section Credits
+ *
+ * Nigel would like to thank the following people for their work:
+ *
+ * Bernard Blackham <bernard@blackham.com.au><BR>
+ * Web page & Wiki administration, some coding. A person without whom
+ * TuxOnIce would not be where it is.
+ *
+ * Michael Frank <mhf@linuxmail.org><BR>
+ * Extensive testing and help with improving stability. I was constantly
+ * amazed by the quality and quantity of Michael's help.
+ *
+ * Pavel Machek <pavel@ucw.cz><BR>
+ * Modifications, defectiveness pointing, being with Gabor at the very
+ * beginning, suspend to swap space, stop all tasks. Port to 2.4.18-ac and
+ * 2.5.17. Even though Pavel and I disagree on the direction suspend to
+ * disk should take, I appreciate the valuable work he did in helping Gabor
+ * get the concept working.
+ *
+ * ..and of course the myriads of TuxOnIce users who have helped diagnose
+ * and fix bugs, made suggestions on how to improve the code, proofread
+ * documentation, and donated time and money.
+ *
+ * Thanks also to corporate sponsors:
+ *
+ * <B>Redhat.</B>Sometime employer from May 2006 (my fault, not Redhat's!).
+ *
+ * <B>Cyclades.com.</B> Nigel's employers from Dec 2004 until May 2006, who
+ * allowed him to work on TuxOnIce and PM related issues on company time.
+ *
+ * <B>LinuxFund.org.</B> Sponsored Nigel's work on TuxOnIce for four months Oct
+ * 2003 to Jan 2004.
+ *
+ * <B>LAC Linux.</B> Donated P4 hardware that enabled development and ongoing
+ * maintenance of SMP and Highmem support.
+ *
+ * <B>OSDL.</B> Provided access to various hardware configurations, make
+ * occasional small donations to the project.
+ */
+
+#include <linux/suspend.h>
+#include <linux/module.h>
+#include <linux/freezer.h>
+#include <generated/utsrelease.h>
+#include <linux/cpu.h>
+#include <linux/console.h>
+#include <linux/writeback.h>
+#include <linux/uaccess.h> /* for get/set_fs & KERNEL_DS on i386 */
+#include <linux/bio.h>
+#include <linux/kgdb.h>
+
+#include "tuxonice.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice_prepare_image.h"
+#include "tuxonice_io.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_power_off.h"
+#include "tuxonice_storage.h"
+#include "tuxonice_checksum.h"
+#include "tuxonice_builtin.h"
+#include "tuxonice_atomic_copy.h"
+#include "tuxonice_alloc.h"
+#include "tuxonice_cluster.h"
+
+/*! Pageset metadata. */
+struct pagedir pagedir2 = {2};
+
+static mm_segment_t oldfs;
+static DEFINE_MUTEX(tuxonice_in_use);
+static int block_dump_save;
+
+int toi_trace_index;
+
+/* Binary signature if an image is present */
+char tuxonice_signature[9] = "\xed\xc3\x02\xe9\x98\x56\xe5\x0c";
+
+unsigned long boot_kernel_data_buffer;
+
+static char *result_strings[] = {
+        "Hibernation was aborted",
+        "The user requested that we cancel the hibernation",
+        "No storage was available",
+        "Insufficient storage was available",
+        "Freezing filesystems and/or tasks failed",
+        "A pre-existing image was used",
+        "We would free memory, but image size limit doesn't allow this",
+        "Unable to free enough memory to hibernate",
+        "Unable to obtain the Power Management Semaphore",
+        "A device suspend/resume returned an error",
+        "A system device suspend/resume returned an error",
+        "The extra pages allowance is too small",
+        "We were unable to successfully prepare an image",
+        "TuxOnIce module initialisation failed",
+        "TuxOnIce module cleanup failed",
+        "I/O errors were encountered",
+        "Ran out of memory",
+        "An error was encountered while reading the image",
+        "Platform preparation failed",
+        "CPU Hotplugging failed",
+        "Architecture specific preparation failed",
+        "Pages needed resaving, but we were told to abort if this happens",
+        "We can't hibernate at the moment (invalid resume= or filewriter "
+                "target?)",
+        "A hibernation preparation notifier chain member cancelled the "
+                "hibernation",
+        "Pre-snapshot preparation failed",
+        "Pre-restore preparation failed",
+        "Failed to disable usermode helpers",
+        "Can't resume from alternate image",
+        "Header reservation too small",
+        "Device Power Management Preparation failed",
+};
+
+/**
+ * toi_finish_anything - cleanup after doing anything
+ * @hibernate_or_resume:        Whether finishing a cycle or attempt at
+ *                                resuming.
+ *
+ * This is our basic clean-up routine, matching start_anything below. We
+ * call cleanup routines, drop module references and restore process fs and
+ * cpus allowed masks, together with the global block_dump variable's value.
+ **/
+void toi_finish_anything(int hibernate_or_resume)
+{
+        toi_running = 0;
+        toi_cleanup_modules(hibernate_or_resume);
+        toi_put_modules();
+        if (hibernate_or_resume) {
+                block_dump = block_dump_save;
+                set_cpus_allowed_ptr(current, cpu_all_mask);
+                toi_alloc_print_debug_stats();
+                atomic_inc(&snapshot_device_available);
+    unlock_system_sleep();
+        }
+
+        set_fs(oldfs);
+        mutex_unlock(&tuxonice_in_use);
+}
+
+/**
+ * toi_start_anything - basic initialisation for TuxOnIce
+ * @toi_or_resume:        Whether starting a cycle or attempt at resuming.
+ *
+ * Our basic initialisation routine. Take references on modules, use the
+ * kernel segment, recheck resume= if no active allocator is set, initialise
+ * modules, save and reset block_dump and ensure we're running on CPU0.
+ **/
+int toi_start_anything(int hibernate_or_resume)
+{
+        mutex_lock(&tuxonice_in_use);
+
+        oldfs = get_fs();
+        set_fs(KERNEL_DS);
+
+        toi_trace_index = 0;
+
+        if (hibernate_or_resume) {
+    lock_system_sleep();
+
+                if (!atomic_add_unless(&snapshot_device_available, -1, 0))
+                        goto snapshotdevice_unavailable;
+        }
+
+        if (hibernate_or_resume == SYSFS_HIBERNATE)
+                toi_print_modules();
+
+        if (toi_get_modules()) {
+                printk(KERN_INFO "TuxOnIce: Get modules failed!\n");
+                goto prehibernate_err;
+        }
+
+        if (hibernate_or_resume) {
+                block_dump_save = block_dump;
+                block_dump = 0;
+                set_cpus_allowed_ptr(current,
+                                cpumask_of(cpumask_first(cpu_online_mask)));
+        }
+
+        if (toi_initialise_modules_early(hibernate_or_resume))
+                goto early_init_err;
+
+        if (!toiActiveAllocator)
+                toi_attempt_to_parse_resume_device(!hibernate_or_resume);
+
+        if (!toi_initialise_modules_late(hibernate_or_resume)) {
+            toi_running = 1; /* For the swsusp code we use :< */
+            return 0;
+        }
+
+        toi_cleanup_modules(hibernate_or_resume);
+early_init_err:
+        if (hibernate_or_resume) {
+                block_dump_save = block_dump;
+                set_cpus_allowed_ptr(current, cpu_all_mask);
+        }
+        toi_put_modules();
+prehibernate_err:
+        if (hibernate_or_resume)
+                atomic_inc(&snapshot_device_available);
+snapshotdevice_unavailable:
+        if (hibernate_or_resume)
+                mutex_unlock(&pm_mutex);
+        set_fs(oldfs);
+        mutex_unlock(&tuxonice_in_use);
+        return -EBUSY;
+}
+
+/*
+ * Nosave page tracking.
+ *
+ * Here rather than in prepare_image because we want to do it once only at the
+ * start of a cycle.
+ */
+
+/**
+ * mark_nosave_pages - set up our Nosave bitmap
+ *
+ * Build a bitmap of Nosave pages from the list. The bitmap allows faster
+ * use when preparing the image.
+ **/
+static void mark_nosave_pages(void)
+{
+        struct nosave_region *region;
+
+        list_for_each_entry(region, &nosave_regions, list) {
+                unsigned long pfn;
+
+                for (pfn = region->start_pfn; pfn < region->end_pfn; pfn++)
+                        if (pfn_valid(pfn)) {
+                                SetPageNosave(pfn_to_page(pfn));
+                        }
+        }
+}
+
+/**
+ * allocate_bitmaps - allocate bitmaps used to record page states
+ *
+ * Allocate the bitmaps we use to record the various TuxOnIce related
+ * page states.
+ **/
+static int allocate_bitmaps(void)
+{
+        if (toi_alloc_bitmap(&pageset1_map) ||
+            toi_alloc_bitmap(&pageset1_copy_map) ||
+            toi_alloc_bitmap(&pageset2_map) ||
+            toi_alloc_bitmap(&io_map) ||
+            toi_alloc_bitmap(&nosave_map) ||
+            toi_alloc_bitmap(&free_map) ||
+            toi_alloc_bitmap(&compare_map) ||
+            toi_alloc_bitmap(&page_resave_map))
+                return 1;
+
+        return 0;
+}
+
+/**
+ * free_bitmaps - free the bitmaps used to record page states
+ *
+ * Free the bitmaps allocated above. It is not an error to call
+ * memory_bm_free on a bitmap that isn't currently allocated.
+ **/
+static void free_bitmaps(void)
+{
+        toi_free_bitmap(&pageset1_map);
+        toi_free_bitmap(&pageset1_copy_map);
+        toi_free_bitmap(&pageset2_map);
+        toi_free_bitmap(&io_map);
+        toi_free_bitmap(&nosave_map);
+        toi_free_bitmap(&free_map);
+        toi_free_bitmap(&compare_map);
+        toi_free_bitmap(&page_resave_map);
+}
+
+/**
+ * io_MB_per_second - return the number of MB/s read or written
+ * @write:        Whether to return the speed at which we wrote.
+ *
+ * Calculate the number of megabytes per second that were read or written.
+ **/
+static int io_MB_per_second(int write)
+{
+        return (toi_bkd.toi_io_time[write][1]) ?
+                MB((unsigned long) toi_bkd.toi_io_time[write][0]) * HZ /
+                toi_bkd.toi_io_time[write][1] : 0;
+}
+
+#define SNPRINTF(a...)         do { len += scnprintf(((char *) buffer) + len, \
+                count - len - 1, ## a); } while (0)
+
+/**
+ * get_debug_info - fill a buffer with debugging information
+ * @buffer:        The buffer to be filled.
+ * @count:        The size of the buffer, in bytes.
+ *
+ * Fill a (usually PAGE_SIZEd) buffer with the debugging info that we will
+ * either printk or return via sysfs.
+ **/
+static int get_toi_debug_info(const char *buffer, int count)
+{
+        int len = 0, i, first_result = 1;
+
+        SNPRINTF("TuxOnIce debugging info:\n");
+        SNPRINTF("- TuxOnIce core  : " TOI_CORE_VERSION "\n");
+        SNPRINTF("- Kernel Version : " UTS_RELEASE "\n");
+        SNPRINTF("- Compiler vers. : %d.%d\n", __GNUC__, __GNUC_MINOR__);
+        SNPRINTF("- Attempt number : %d\n", nr_hibernates);
+        SNPRINTF("- Parameters     : %ld %ld %ld %d %ld %ld\n",
+                        toi_result,
+                        toi_bkd.toi_action,
+                        toi_bkd.toi_debug_state,
+                        toi_bkd.toi_default_console_level,
+                        image_size_limit,
+                        toi_poweroff_method);
+        SNPRINTF("- Overall expected compression percentage: %d.\n",
+                        100 - toi_expected_compression_ratio());
+        len += toi_print_module_debug_info(((char *) buffer) + len,
+                        count - len - 1);
+        if (toi_bkd.toi_io_time[0][1]) {
+                if ((io_MB_per_second(0) < 5) || (io_MB_per_second(1) < 5)) {
+                        SNPRINTF("- I/O speed: Write %ld KB/s",
+                          (KB((unsigned long) toi_bkd.toi_io_time[0][0]) * HZ /
+                          toi_bkd.toi_io_time[0][1]));
+                        if (toi_bkd.toi_io_time[1][1])
+                                SNPRINTF(", Read %ld KB/s",
+                                  (KB((unsigned long)
+                                      toi_bkd.toi_io_time[1][0]) * HZ /
+                                  toi_bkd.toi_io_time[1][1]));
+                } else {
+                        SNPRINTF("- I/O speed: Write %ld MB/s",
+                         (MB((unsigned long) toi_bkd.toi_io_time[0][0]) * HZ /
+                          toi_bkd.toi_io_time[0][1]));
+                        if (toi_bkd.toi_io_time[1][1])
+                                SNPRINTF(", Read %ld MB/s",
+                                 (MB((unsigned long)
+                                     toi_bkd.toi_io_time[1][0]) * HZ /
+                                  toi_bkd.toi_io_time[1][1]));
+                }
+                SNPRINTF(".\n");
+        } else
+                SNPRINTF("- No I/O speed stats available.\n");
+        SNPRINTF("- Extra pages    : %lu used/%lu.\n",
+                        extra_pd1_pages_used, extra_pd1_pages_allowance);
+
+        for (i = 0; i < TOI_NUM_RESULT_STATES; i++)
+                if (test_result_state(i)) {
+                        SNPRINTF("%s: %s.\n", first_result ?
+                                        "- Result         " :
+                                        "                 ",
+                                        result_strings[i]);
+                        first_result = 0;
+                }
+        if (first_result)
+                SNPRINTF("- Result         : %s.\n", nr_hibernates ?
+                        "Succeeded" :
+                        "No hibernation attempts so far");
+        return len;
+}
+
+#ifdef CONFIG_TOI_INCREMENTAL
+/**
+ * get_toi_page_state - fill a buffer with page state information
+ * @buffer:        The buffer to be filled.
+ * @count:        The size of the buffer, in bytes.
+ *
+ * Fill a (usually PAGE_SIZEd) buffer with the debugging info that we will
+ * either printk or return via sysfs.
+ **/
+static int get_toi_page_state(const char *buffer, int count)
+{
+    int free = 0, untracked = 0, dirty = 0, ro = 0, invalid = 0, other = 0, total = 0;
+    int len = 0;
+    struct zone *zone;
+    int allocated_bitmaps = 0;
+
+    set_cpus_allowed_ptr(current,
+            cpumask_of(cpumask_first(cpu_online_mask)));
+
+    if (!free_map) {
+        BUG_ON(toi_alloc_bitmap(&free_map));
+        allocated_bitmaps = 1;
+    }
+
+    toi_generate_free_page_map();
+
+    for_each_populated_zone(zone) {
+        unsigned long loop;
+
+        total += zone->spanned_pages;
+
+        for (loop = 0; loop < zone->spanned_pages; loop++) {
+            unsigned long pfn = zone->zone_start_pfn + loop;
+            struct page *page;
+            int chunk_size;
+
+            if (!pfn_valid(pfn)) {
+                continue;
+            }
+
+            chunk_size = toi_size_of_free_region(zone, pfn);
+            if (chunk_size) {
+                /*
+                 * If the page gets allocated, it will be need
+                 * saving in an image.
+                 * Don't bother with explicitly removing any
+                 * RO protection applied below.
+                 * We'll SetPageTOI_Dirty(page) if/when it
+                 * gets allocated.
+                 */
+                free += chunk_size;
+                loop += chunk_size - 1;
+                continue;
+            }
+
+            page = pfn_to_page(pfn);
+
+            if (PageTOI_Untracked(page)) {
+                untracked++;
+            } else if (PageTOI_RO(page)) {
+                ro++;
+            } else if (PageTOI_Dirty(page)) {
+                dirty++;
+            } else {
+                printk("Page %ld state 'other'.\n", pfn);
+                other++;
+            }
+        }
+    }
+
+    if (allocated_bitmaps) {
+        toi_free_bitmap(&free_map);
+    }
+
+    set_cpus_allowed_ptr(current, cpu_all_mask);
+
+    SNPRINTF("TuxOnIce page breakdown:\n");
+    SNPRINTF("- Free           : %d\n", free);
+    SNPRINTF("- Untracked      : %d\n", untracked);
+    SNPRINTF("- Read only      : %d\n", ro);
+    SNPRINTF("- Dirty          : %d\n", dirty);
+    SNPRINTF("- Other          : %d\n", other);
+    SNPRINTF("- Invalid        : %d\n", invalid);
+    SNPRINTF("- Total          : %d\n", total);
+    return len;
+}
+#endif
+
+/**
+ * do_cleanup - cleanup after attempting to hibernate or resume
+ * @get_debug_info:        Whether to allocate and return debugging info.
+ *
+ * Cleanup after attempting to hibernate or resume, possibly getting
+ * debugging info as we do so.
+ **/
+static void do_cleanup(int get_debug_info, int restarting)
+{
+        int i = 0;
+        char *buffer = NULL;
+
+        trap_non_toi_io = 0;
+
+        if (get_debug_info)
+                toi_prepare_status(DONT_CLEAR_BAR, "Cleaning up...");
+
+        free_checksum_pages();
+
+        toi_cbw_restore();
+        toi_free_cbw_data();
+
+        if (get_debug_info)
+                buffer = (char *) toi_get_zeroed_page(20, TOI_ATOMIC_GFP);
+
+        if (buffer)
+                i = get_toi_debug_info(buffer, PAGE_SIZE);
+
+        toi_free_extra_pagedir_memory();
+
+        pagedir1.size = 0;
+        pagedir2.size = 0;
+        set_highmem_size(pagedir1, 0);
+        set_highmem_size(pagedir2, 0);
+
+        if (boot_kernel_data_buffer) {
+                if (!test_toi_state(TOI_BOOT_KERNEL))
+                        toi_free_page(37, boot_kernel_data_buffer);
+                boot_kernel_data_buffer = 0;
+        }
+
+        if (test_toi_state(TOI_DEVICE_HOTPLUG_LOCKED)) {
+                unlock_device_hotplug();
+                clear_toi_state(TOI_DEVICE_HOTPLUG_LOCKED);
+        }
+
+        clear_toi_state(TOI_BOOT_KERNEL);
+        if (current->flags & PF_SUSPEND_TASK)
+                thaw_processes();
+
+        if (!restarting)
+                toi_stop_other_threads();
+
+        if (toi_keeping_image &&
+            !test_result_state(TOI_ABORTED)) {
+                toi_message(TOI_ANY_SECTION, TOI_LOW, 1,
+                        "TuxOnIce: Not invalidating the image due "
+                        "to Keep Image or Incremental Image being enabled.");
+                set_result_state(TOI_KEPT_IMAGE);
+
+                /*
+                 * For an incremental image, free unused storage so
+                 * swap (if any) can be used for normal system operation,
+                 * if so desired.
+                 */
+
+                toiActiveAllocator->free_unused_storage();
+        } else
+                if (toiActiveAllocator)
+                        toiActiveAllocator->remove_image();
+
+        free_bitmaps();
+        usermodehelper_enable();
+
+        if (test_toi_state(TOI_NOTIFIERS_PREPARE)) {
+                pm_notifier_call_chain(PM_POST_HIBERNATION);
+                clear_toi_state(TOI_NOTIFIERS_PREPARE);
+        }
+
+        if (buffer && i) {
+                /* Printk can only handle 1023 bytes, including
+                 * its level mangling. */
+                for (i = 0; i < 3; i++)
+                        printk(KERN_ERR "%s", buffer + (1023 * i));
+                toi_free_page(20, (unsigned long) buffer);
+        }
+
+        if (!restarting)
+                toi_cleanup_console();
+
+        free_attention_list();
+
+        if (!restarting)
+                toi_deactivate_storage(0);
+
+        clear_toi_state(TOI_IGNORE_LOGLEVEL);
+        clear_toi_state(TOI_TRYING_TO_RESUME);
+        clear_toi_state(TOI_NOW_RESUMING);
+}
+
+/**
+ * check_still_keeping_image - we kept an image; check whether to reuse it.
+ *
+ * We enter this routine when we have kept an image. If the user has said they
+ * want to still keep it, all we need to do is powerdown. If powering down
+ * means hibernating to ram and the power doesn't run out, we'll return 1.
+ * If we do power off properly or the battery runs out, we'll resume via the
+ * normal paths.
+ *
+ * If the user has said they want to remove the previously kept image, we
+ * remove it, and return 0. We'll then store a new image.
+ **/
+static int check_still_keeping_image(void)
+{
+    if (toi_keeping_image) {
+        if (!test_action_state(TOI_INCREMENTAL_IMAGE)) {
+            printk(KERN_INFO "Image already stored: powering down "
+                    "immediately.");
+            do_toi_step(STEP_HIBERNATE_POWERDOWN);
+            return 1;
+        }
+        /**
+         * Incremental image - need to write new part.
+         * We detect that we're writing an incremental image by looking
+         * at test_result_state(TOI_KEPT_IMAGE)
+         **/
+        return 0;
+    }
+
+    printk(KERN_INFO "Invalidating previous image.\n");
+    toiActiveAllocator->remove_image();
+
+    return 0;
+}
+
+/**
+ * toi_init - prepare to hibernate to disk
+ *
+ * Initialise variables & data structures, in preparation for
+ * hibernating to disk.
+ **/
+static int toi_init(int restarting)
+{
+        int result, i, j;
+
+        toi_result = 0;
+
+        printk(KERN_INFO "Initiating a hibernation cycle.\n");
+
+        nr_hibernates++;
+
+        for (i = 0; i < 2; i++)
+                for (j = 0; j < 2; j++)
+                        toi_bkd.toi_io_time[i][j] = 0;
+
+        if (!test_toi_state(TOI_CAN_HIBERNATE) ||
+            allocate_bitmaps())
+                return 1;
+
+        mark_nosave_pages();
+
+        if (!restarting)
+                toi_prepare_console();
+
+        result = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
+        if (result) {
+                set_result_state(TOI_NOTIFIERS_PREPARE_FAILED);
+                return 1;
+        }
+        set_toi_state(TOI_NOTIFIERS_PREPARE);
+
+        if (!restarting) {
+                printk(KERN_ERR "Starting other threads.");
+                toi_start_other_threads();
+        }
+
+        result = usermodehelper_disable();
+        if (result) {
+                printk(KERN_ERR "TuxOnIce: Failed to disable usermode "
+                                "helpers\n");
+                set_result_state(TOI_USERMODE_HELPERS_ERR);
+                return 1;
+        }
+
+        boot_kernel_data_buffer = toi_get_zeroed_page(37, TOI_ATOMIC_GFP);
+        if (!boot_kernel_data_buffer) {
+                printk(KERN_ERR "TuxOnIce: Failed to allocate "
+                                "boot_kernel_data_buffer.\n");
+                set_result_state(TOI_OUT_OF_MEMORY);
+                return 1;
+        }
+
+        toi_allocate_cbw_data();
+
+        return 0;
+}
+
+/**
+ * can_hibernate - perform basic 'Can we hibernate?' tests
+ *
+ * Perform basic tests that must pass if we're going to be able to hibernate:
+ * Can we get the pm_mutex? Is resume= valid (we need to know where to write
+ * the image header).
+ **/
+static int can_hibernate(void)
+{
+        if (!test_toi_state(TOI_CAN_HIBERNATE))
+                toi_attempt_to_parse_resume_device(0);
+
+        if (!test_toi_state(TOI_CAN_HIBERNATE)) {
+                printk(KERN_INFO "TuxOnIce: Hibernation is disabled.\n"
+                        "This may be because you haven't put something along "
+                        "the lines of\n\nresume=swap:/dev/hda1\n\n"
+                        "in lilo.conf or equivalent. (Where /dev/hda1 is your "
+                        "swap partition).\n");
+                set_abort_result(TOI_CANT_SUSPEND);
+                return 0;
+        }
+
+        if (strlen(alt_resume_param)) {
+                attempt_to_parse_alt_resume_param();
+
+                if (!strlen(alt_resume_param)) {
+                        printk(KERN_INFO "Alternate resume parameter now "
+                                        "invalid. Aborting.\n");
+                        set_abort_result(TOI_CANT_USE_ALT_RESUME);
+                        return 0;
+                }
+        }
+
+        return 1;
+}
+
+/**
+ * do_post_image_write - having written an image, figure out what to do next
+ *
+ * After writing an image, we might load an alternate image or power down.
+ * Powering down might involve hibernating to ram, in which case we also
+ * need to handle reloading pageset2.
+ **/
+static int do_post_image_write(void)
+{
+        /* If switching images fails, do normal powerdown */
+        if (alt_resume_param[0])
+                do_toi_step(STEP_RESUME_ALT_IMAGE);
+
+        toi_power_down();
+
+        barrier();
+        mb();
+        return 0;
+}
+
+/**
+ * __save_image - do the hard work of saving the image
+ *
+ * High level routine for getting the image saved. The key assumptions made
+ * are that processes have been frozen and sufficient memory is available.
+ *
+ * We also exit through here at resume time, coming back from toi_hibernate
+ * after the atomic restore. This is the reason for the toi_in_hibernate
+ * test.
+ **/
+static int __save_image(void)
+{
+        int temp_result, did_copy = 0;
+
+        toi_prepare_status(DONT_CLEAR_BAR, "Starting to save the image..");
+
+        toi_message(TOI_ANY_SECTION, TOI_LOW, 1,
+                " - Final values: %d and %d.",
+                pagedir1.size, pagedir2.size);
+
+        toi_cond_pause(1, "About to write pagedir2.");
+
+        temp_result = write_pageset(&pagedir2);
+
+        if (temp_result == -1 || test_result_state(TOI_ABORTED))
+                return 1;
+
+        toi_cond_pause(1, "About to copy pageset 1.");
+
+        if (test_result_state(TOI_ABORTED))
+                return 1;
+
+        toi_deactivate_storage(1);
+
+        toi_prepare_status(DONT_CLEAR_BAR, "Doing atomic copy/restore.");
+
+        toi_in_hibernate = 1;
+
+        if (toi_go_atomic(PMSG_FREEZE, 1))
+                goto Failed;
+
+        temp_result = toi_hibernate();
+
+#ifdef CONFIG_KGDB
+        if (test_action_state(TOI_POST_RESUME_BREAKPOINT))
+                kgdb_breakpoint();
+#endif
+
+        if (!temp_result)
+                did_copy = 1;
+
+        /* We return here at resume time too! */
+        toi_end_atomic(ATOMIC_ALL_STEPS, toi_in_hibernate, temp_result);
+
+Failed:
+        if (toi_activate_storage(1))
+                panic("Failed to reactivate our storage.");
+
+        /* Resume time? */
+        if (!toi_in_hibernate) {
+                copyback_post();
+                return 0;
+        }
+
+        /* Nope. Hibernating. So, see if we can save the image... */
+
+        if (temp_result || test_result_state(TOI_ABORTED)) {
+                if (did_copy)
+                        goto abort_reloading_pagedir_two;
+                else
+                        return 1;
+        }
+
+        toi_update_status(pagedir2.size, pagedir1.size + pagedir2.size,
+                        NULL);
+
+        if (test_result_state(TOI_ABORTED))
+                goto abort_reloading_pagedir_two;
+
+        toi_cond_pause(1, "About to write pageset1.");
+
+        toi_message(TOI_ANY_SECTION, TOI_LOW, 1, "-- Writing pageset1");
+
+        temp_result = write_pageset(&pagedir1);
+
+        /* We didn't overwrite any memory, so no reread needs to be done. */
+        if (test_action_state(TOI_TEST_FILTER_SPEED) ||
+            test_action_state(TOI_TEST_BIO))
+                return 1;
+
+        if (temp_result == 1 || test_result_state(TOI_ABORTED))
+                goto abort_reloading_pagedir_two;
+
+        toi_cond_pause(1, "About to write header.");
+
+        if (test_result_state(TOI_ABORTED))
+                goto abort_reloading_pagedir_two;
+
+        temp_result = write_image_header();
+
+        if (!temp_result && !test_result_state(TOI_ABORTED))
+                return 0;
+
+abort_reloading_pagedir_two:
+        temp_result = read_pageset2(1);
+
+        /* If that failed, we're sunk. Panic! */
+        if (temp_result)
+                panic("Attempt to reload pagedir 2 while aborting "
+                                "a hibernate failed.");
+
+        return 1;
+}
+
+static void map_ps2_pages(int enable)
+{
+        unsigned long pfn = 0;
+
+        memory_bm_position_reset(pageset2_map);
+        pfn = memory_bm_next_pfn(pageset2_map, 0);
+
+        while (pfn != BM_END_OF_MAP) {
+                struct page *page = pfn_to_page(pfn);
+                kernel_map_pages(page, 1, enable);
+                pfn = memory_bm_next_pfn(pageset2_map, 0);
+        }
+}
+
+/**
+ * do_save_image - save the image and handle the result
+ *
+ * Save the prepared image. If we fail or we're in the path returning
+ * from the atomic restore, cleanup.
+ **/
+static int do_save_image(void)
+{
+        int result;
+        map_ps2_pages(0);
+        result = __save_image();
+        map_ps2_pages(1);
+        return result;
+}
+
+/**
+ * do_prepare_image - try to prepare an image
+ *
+ * Seek to initialise and prepare an image to be saved. On failure,
+ * cleanup.
+ **/
+static int do_prepare_image(void)
+{
+        int restarting = test_result_state(TOI_EXTRA_PAGES_ALLOW_TOO_SMALL);
+
+        if (!restarting && toi_activate_storage(0))
+                return 1;
+
+        /*
+         * If kept image and still keeping image and hibernating to RAM, (non
+         * incremental image case) we will return 1 after hibernating and
+         * resuming (provided the power doesn't run out. In that case, we skip
+         * directly to cleaning up and exiting.
+         */
+
+        if (!can_hibernate() ||
+            (test_result_state(TOI_KEPT_IMAGE) &&
+             check_still_keeping_image()))
+                return 1;
+
+        if (toi_init(restarting) || toi_prepare_image() ||
+                        test_result_state(TOI_ABORTED))
+                return 1;
+
+        trap_non_toi_io = 1;
+
+        return 0;
+}
+
+/**
+ * do_check_can_resume - find out whether an image has been stored
+ *
+ * Read whether an image exists. We use the same routine as the
+ * image_exists sysfs entry, and just look to see whether the
+ * first character in the resulting buffer is a '1'.
+ **/
+int do_check_can_resume(void)
+{
+        int result = -1;
+
+        if (toi_activate_storage(0))
+                return -1;
+
+        if (!test_toi_state(TOI_RESUME_DEVICE_OK))
+                toi_attempt_to_parse_resume_device(1);
+
+        if (toiActiveAllocator)
+                result = toiActiveAllocator->image_exists(1);
+
+        toi_deactivate_storage(0);
+        return result;
+}
+
+/**
+ * do_load_atomic_copy - load the first part of an image, if it exists
+ *
+ * Check whether we have an image. If one exists, do sanity checking
+ * (possibly invalidating the image or even rebooting if the user
+ * requests that) before loading it into memory in preparation for the
+ * atomic restore.
+ *
+ * If and only if we have an image loaded and ready to restore, we return 1.
+ **/
+static int do_load_atomic_copy(void)
+{
+        int read_image_result = 0;
+
+        if (sizeof(swp_entry_t) != sizeof(long)) {
+                printk(KERN_WARNING "TuxOnIce: The size of swp_entry_t != size"
+                        " of long. Please report this!\n");
+                return 1;
+        }
+
+        if (!resume_file[0])
+                printk(KERN_WARNING "TuxOnIce: "
+                        "You need to use a resume= command line parameter to "
+                        "tell TuxOnIce where to look for an image.\n");
+
+        toi_activate_storage(0);
+
+        if (!(test_toi_state(TOI_RESUME_DEVICE_OK)) &&
+                !toi_attempt_to_parse_resume_device(0)) {
+                /*
+                 * Without a usable storage device we can do nothing -
+                 * even if noresume is given
+                 */
+
+                if (!toiNumAllocators)
+                        printk(KERN_ALERT "TuxOnIce: "
+                          "No storage allocators have been registered.\n");
+                else
+                        printk(KERN_ALERT "TuxOnIce: "
+                                "Missing or invalid storage location "
+                                "(resume= parameter). Please correct and "
+                                "rerun lilo (or equivalent) before "
+                                "hibernating.\n");
+                toi_deactivate_storage(0);
+                return 1;
+        }
+
+        if (allocate_bitmaps())
+                return 1;
+
+        read_image_result = read_pageset1(); /* non fatal error ignored */
+
+        if (test_toi_state(TOI_NORESUME_SPECIFIED))
+                clear_toi_state(TOI_NORESUME_SPECIFIED);
+
+        toi_deactivate_storage(0);
+
+        if (read_image_result)
+                return 1;
+
+        return 0;
+}
+
+/**
+ * prepare_restore_load_alt_image - save & restore alt image variables
+ *
+ * Save and restore the pageset1 maps, when loading an alternate image.
+ **/
+static void prepare_restore_load_alt_image(int prepare)
+{
+        static struct memory_bitmap *pageset1_map_save, *pageset1_copy_map_save;
+
+        if (prepare) {
+                pageset1_map_save = pageset1_map;
+                pageset1_map = NULL;
+                pageset1_copy_map_save = pageset1_copy_map;
+                pageset1_copy_map = NULL;
+                set_toi_state(TOI_LOADING_ALT_IMAGE);
+                toi_reset_alt_image_pageset2_pfn();
+        } else {
+                toi_free_bitmap(&pageset1_map);
+                pageset1_map = pageset1_map_save;
+                toi_free_bitmap(&pageset1_copy_map);
+                pageset1_copy_map = pageset1_copy_map_save;
+                clear_toi_state(TOI_NOW_RESUMING);
+                clear_toi_state(TOI_LOADING_ALT_IMAGE);
+        }
+}
+
+/**
+ * do_toi_step - perform a step in hibernating or resuming
+ *
+ * Perform a step in hibernating or resuming an image. This abstraction
+ * is in preparation for implementing cluster support, and perhaps replacing
+ * uswsusp too (haven't looked whether that's possible yet).
+ **/
+int do_toi_step(int step)
+{
+        switch (step) {
+        case STEP_HIBERNATE_PREPARE_IMAGE:
+                return do_prepare_image();
+        case STEP_HIBERNATE_SAVE_IMAGE:
+                return do_save_image();
+        case STEP_HIBERNATE_POWERDOWN:
+                return do_post_image_write();
+        case STEP_RESUME_CAN_RESUME:
+                return do_check_can_resume();
+        case STEP_RESUME_LOAD_PS1:
+                return do_load_atomic_copy();
+        case STEP_RESUME_DO_RESTORE:
+                /*
+                 * If we succeed, this doesn't return.
+                 * Instead, we return from do_save_image() in the
+                 * hibernated kernel.
+                 */
+                return toi_atomic_restore();
+        case STEP_RESUME_ALT_IMAGE:
+                printk(KERN_INFO "Trying to resume alternate image.\n");
+                toi_in_hibernate = 0;
+                save_restore_alt_param(SAVE, NOQUIET);
+                prepare_restore_load_alt_image(1);
+                if (!do_check_can_resume()) {
+                        printk(KERN_INFO "Nothing to resume from.\n");
+                        goto out;
+                }
+                if (!do_load_atomic_copy())
+                        toi_atomic_restore();
+
+                printk(KERN_INFO "Failed to load image.\n");
+out:
+                prepare_restore_load_alt_image(0);
+                save_restore_alt_param(RESTORE, NOQUIET);
+                break;
+        case STEP_CLEANUP:
+                do_cleanup(1, 0);
+                break;
+        case STEP_QUIET_CLEANUP:
+                do_cleanup(0, 0);
+                break;
+        }
+
+        return 0;
+}
+
+/* -- Functions for kickstarting a hibernate or resume --- */
+
+/**
+ * toi_try_resume - try to do the steps in resuming
+ *
+ * Check if we have an image and if so try to resume. Clear the status
+ * flags too.
+ **/
+void toi_try_resume(void)
+{
+        set_toi_state(TOI_TRYING_TO_RESUME);
+        resume_attempted = 1;
+
+        current->flags |= PF_MEMALLOC;
+        toi_start_other_threads();
+
+        if (do_toi_step(STEP_RESUME_CAN_RESUME) &&
+                        !do_toi_step(STEP_RESUME_LOAD_PS1))
+                do_toi_step(STEP_RESUME_DO_RESTORE);
+
+        toi_stop_other_threads();
+        do_cleanup(0, 0);
+
+        current->flags &= ~PF_MEMALLOC;
+
+        clear_toi_state(TOI_IGNORE_LOGLEVEL);
+        clear_toi_state(TOI_TRYING_TO_RESUME);
+        clear_toi_state(TOI_NOW_RESUMING);
+}
+
+/**
+ * toi_sys_power_disk_try_resume - wrapper calling toi_try_resume
+ *
+ * Wrapper for when __toi_try_resume is called from swsusp resume path,
+ * rather than from echo > /sys/power/tuxonice/do_resume.
+ **/
+static void toi_sys_power_disk_try_resume(void)
+{
+        resume_attempted = 1;
+
+        /*
+         * There's a comment in kernel/power/disk.c that indicates
+         * we should be able to use mutex_lock_nested below. That
+         * doesn't seem to cut it, though, so let's just turn lockdep
+         * off for now.
+         */
+        lockdep_off();
+
+        if (toi_start_anything(SYSFS_RESUMING))
+                goto out;
+
+        toi_try_resume();
+
+        /*
+         * For initramfs, we have to clear the boot time
+         * flag after trying to resume
+         */
+        clear_toi_state(TOI_BOOT_TIME);
+
+        toi_finish_anything(SYSFS_RESUMING);
+out:
+        lockdep_on();
+}
+
+/**
+ * toi_try_hibernate - try to start a hibernation cycle
+ *
+ * Start a hibernation cycle, coming in from either
+ * echo > /sys/power/tuxonice/do_suspend
+ *
+ * or
+ *
+ * echo disk > /sys/power/state
+ *
+ * In the later case, we come in without pm_sem taken; in the
+ * former, it has been taken.
+ **/
+int toi_try_hibernate(void)
+{
+        int result = 0, sys_power_disk = 0, retries = 0;
+
+        if (!mutex_is_locked(&tuxonice_in_use)) {
+                /* Came in via /sys/power/disk */
+                if (toi_start_anything(SYSFS_HIBERNATING))
+                        return -EBUSY;
+                sys_power_disk = 1;
+        }
+
+        current->flags |= PF_MEMALLOC;
+
+        if (test_toi_state(TOI_CLUSTER_MODE)) {
+                toi_initiate_cluster_hibernate();
+                goto out;
+        }
+
+prepare:
+        result = do_toi_step(STEP_HIBERNATE_PREPARE_IMAGE);
+
+        if (result)
+                goto out;
+
+        if (test_action_state(TOI_FREEZER_TEST))
+                goto out_restore_gfp_mask;
+
+        result = do_toi_step(STEP_HIBERNATE_SAVE_IMAGE);
+
+        if (test_result_state(TOI_EXTRA_PAGES_ALLOW_TOO_SMALL)) {
+                if (retries < 2) {
+                        do_cleanup(0, 1);
+                        retries++;
+                        clear_result_state(TOI_ABORTED);
+                        extra_pd1_pages_allowance = extra_pd1_pages_used + 500;
+                        printk(KERN_INFO "Automatically adjusting the extra"
+                                " pages allowance to %ld and restarting.\n",
+                                extra_pd1_pages_allowance);
+                        pm_restore_gfp_mask();
+                        goto prepare;
+                }
+
+                printk(KERN_INFO "Adjusted extra pages allowance twice and "
+                        "still couldn't hibernate successfully. Giving up.");
+        }
+
+        /* This code runs at resume time too! */
+        if (!result && toi_in_hibernate)
+                result = do_toi_step(STEP_HIBERNATE_POWERDOWN);
+
+out_restore_gfp_mask:
+        pm_restore_gfp_mask();
+out:
+        do_cleanup(1, 0);
+        current->flags &= ~PF_MEMALLOC;
+
+        if (sys_power_disk)
+                toi_finish_anything(SYSFS_HIBERNATING);
+
+        return result;
+}
+
+/*
+ * channel_no: If !0, -c <channel_no> is added to args (userui).
+ */
+int toi_launch_userspace_program(char *command, int channel_no,
+                int wait, int debug)
+{
+        int retval;
+        static char *envp[] = {
+                        "HOME=/",
+                        "TERM=linux",
+                        "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
+                        NULL };
+        static char *argv[] = { NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL
+                };
+        char *channel = NULL;
+        int arg = 0, size;
+        char test_read[255];
+        char *orig_posn = command;
+
+        if (!strlen(orig_posn))
+                return 1;
+
+        if (channel_no) {
+                channel = toi_kzalloc(4, 6, GFP_KERNEL);
+                if (!channel) {
+                        printk(KERN_INFO "Failed to allocate memory in "
+                                "preparing to launch userspace program.\n");
+                        return 1;
+                }
+        }
+
+        /* Up to 6 args supported */
+        while (arg < 6) {
+                sscanf(orig_posn, "%s", test_read);
+                size = strlen(test_read);
+                if (!(size))
+                        break;
+                argv[arg] = toi_kzalloc(5, size + 1, TOI_ATOMIC_GFP);
+                strcpy(argv[arg], test_read);
+                orig_posn += size + 1;
+                *test_read = 0;
+                arg++;
+        }
+
+        if (channel_no) {
+                sprintf(channel, "-c%d", channel_no);
+                argv[arg] = channel;
+        } else
+                arg--;
+
+        if (debug) {
+                argv[++arg] = toi_kzalloc(5, 8, TOI_ATOMIC_GFP);
+                strcpy(argv[arg], "--debug");
+        }
+
+        retval = call_usermodehelper(argv[0], argv, envp, wait);
+
+        /*
+         * If the program reports an error, retval = 256. Don't complain
+         * about that here.
+         */
+        if (retval && retval != 256)
+                printk(KERN_ERR "Failed to launch userspace program '%s': "
+                                "Error %d\n", command, retval);
+
+        {
+                int i;
+                for (i = 0; i < arg; i++)
+                        if (argv[i] && argv[i] != channel)
+                                toi_kfree(5, argv[i], sizeof(*argv[i]));
+        }
+
+        toi_kfree(4, channel, sizeof(*channel));
+
+        return retval;
+}
+
+/*
+ * This array contains entries that are automatically registered at
+ * boot. Modules and the console code register their own entries separately.
+ */
+static struct toi_sysfs_data sysfs_params[] = {
+        SYSFS_LONG("extra_pages_allowance", SYSFS_RW,
+                        &extra_pd1_pages_allowance, 0, LONG_MAX, 0),
+        SYSFS_CUSTOM("image_exists", SYSFS_RW, image_exists_read,
+                        image_exists_write, SYSFS_NEEDS_SM_FOR_BOTH, NULL),
+        SYSFS_STRING("resume", SYSFS_RW, resume_file, 255,
+                        SYSFS_NEEDS_SM_FOR_WRITE,
+                        attempt_to_parse_resume_device2),
+        SYSFS_STRING("alt_resume_param", SYSFS_RW, alt_resume_param, 255,
+                        SYSFS_NEEDS_SM_FOR_WRITE,
+                        attempt_to_parse_alt_resume_param),
+        SYSFS_CUSTOM("debug_info", SYSFS_READONLY, get_toi_debug_info, NULL, 0,
+                        NULL),
+        SYSFS_BIT("ignore_rootfs", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_IGNORE_ROOTFS, 0),
+        SYSFS_LONG("image_size_limit", SYSFS_RW, &image_size_limit, -2,
+                        INT_MAX, 0),
+        SYSFS_UL("last_result", SYSFS_RW, &toi_result, 0, 0, 0),
+        SYSFS_BIT("no_multithreaded_io", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_NO_MULTITHREADED_IO, 0),
+        SYSFS_BIT("no_flusher_thread", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_NO_FLUSHER_THREAD, 0),
+        SYSFS_BIT("full_pageset2", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_PAGESET2_FULL, 0),
+        SYSFS_BIT("reboot", SYSFS_RW, &toi_bkd.toi_action, TOI_REBOOT, 0),
+        SYSFS_BIT("replace_swsusp", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_REPLACE_SWSUSP, 0),
+        SYSFS_STRING("resume_commandline", SYSFS_RW,
+                        toi_bkd.toi_nosave_commandline, COMMAND_LINE_SIZE, 0,
+                        NULL),
+        SYSFS_STRING("version", SYSFS_READONLY, TOI_CORE_VERSION, 0, 0, NULL),
+        SYSFS_BIT("freezer_test", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_FREEZER_TEST, 0),
+        SYSFS_BIT("test_bio", SYSFS_RW, &toi_bkd.toi_action, TOI_TEST_BIO, 0),
+        SYSFS_BIT("test_filter_speed", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_TEST_FILTER_SPEED, 0),
+        SYSFS_BIT("no_pageset2", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_NO_PAGESET2, 0),
+        SYSFS_BIT("no_pageset2_if_unneeded", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_NO_PS2_IF_UNNEEDED, 0),
+        SYSFS_STRING("binary_signature", SYSFS_READONLY,
+                        tuxonice_signature, 9, 0, NULL),
+        SYSFS_INT("max_workers", SYSFS_RW, &toi_max_workers, 0, NR_CPUS, 0,
+                        NULL),
+#ifdef CONFIG_KGDB
+        SYSFS_BIT("post_resume_breakpoint", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_POST_RESUME_BREAKPOINT, 0),
+#endif
+        SYSFS_BIT("no_readahead", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_NO_READAHEAD, 0),
+        SYSFS_BIT("trace_debug_on", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_TRACE_DEBUG_ON, 0),
+#ifdef CONFIG_TOI_KEEP_IMAGE
+        SYSFS_BIT("keep_image", SYSFS_RW , &toi_bkd.toi_action, TOI_KEEP_IMAGE,
+                        0),
+#endif
+#ifdef CONFIG_TOI_INCREMENTAL
+        SYSFS_CUSTOM("pagestate", SYSFS_READONLY, get_toi_page_state, NULL, 0,
+                        NULL),
+        SYSFS_BIT("incremental", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_INCREMENTAL_IMAGE, 1),
+#endif
+};
+
+static struct toi_core_fns my_fns = {
+        .get_nonconflicting_page = __toi_get_nonconflicting_page,
+        .post_context_save = __toi_post_context_save,
+        .try_hibernate = toi_try_hibernate,
+        .try_resume = toi_sys_power_disk_try_resume,
+};
+
+/**
+ * core_load - initialisation of TuxOnIce core
+ *
+ * Initialise the core, beginning with sysfs. Checksum and so on are part of
+ * the core, but have their own initialisation routines because they either
+ * aren't compiled in all the time or have their own subdirectories.
+ **/
+static __init int core_load(void)
+{
+        int i,
+            numfiles = sizeof(sysfs_params) / sizeof(struct toi_sysfs_data);
+
+        printk(KERN_INFO "TuxOnIce " TOI_CORE_VERSION
+                        " (http://tuxonice.net)\n");
+
+        if (!hibernation_available()) {
+          printk(KERN_INFO "TuxOnIce disabled due to request for hibernation"
+              " to be disabled in this kernel.\n");
+          return 1;
+        }
+
+        if (toi_sysfs_init())
+                return 1;
+
+        for (i = 0; i < numfiles; i++)
+                toi_register_sysfs_file(tuxonice_kobj, &sysfs_params[i]);
+
+        toi_core_fns = &my_fns;
+
+        if (toi_alloc_init())
+                return 1;
+        if (toi_checksum_init())
+                return 1;
+        if (toi_usm_init())
+                return 1;
+        if (toi_ui_init())
+                return 1;
+        if (toi_poweroff_init())
+                return 1;
+        if (toi_cluster_init())
+                return 1;
+        if (toi_cbw_init())
+                return 1;
+
+        return 0;
+}
+
+late_initcall(core_load);
diff --git a/kernel/power/tuxonice_incremental.c b/kernel/power/tuxonice_incremental.c
new file mode 100644
index 000000000..a8c5f3660
--- /dev/null
+++ b/kernel/power/tuxonice_incremental.c
@@ -0,0 +1,402 @@
+/*
+ * kernel/power/tuxonice_incremental.c
+ *
+ * Copyright (C) 2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * This file contains routines related to storing incremental images - that
+ * is, retaining an image after an initial cycle and then storing incremental
+ * changes on subsequent hibernations.
+ *
+ * Based in part on on...
+ *
+ * Debug helper to dump the current kernel pagetables of the system
+ * so that we can see what the various memory ranges are set to.
+ *
+ * (C) Copyright 2008 Intel Corporation
+ *
+ * Author: Arjan van de Ven <arjan@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ */
+
+#include <linux/mm.h>
+#include <linux/tuxonice.h>
+#include <linux/sched.h>
+#include <asm/pgtable.h>
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+#include <asm/page.h>
+#include "tuxonice_pageflags.h"
+#include "tuxonice_builtin.h"
+#include "power.h"
+
+int toi_do_incremental_initcall;
+
+extern void kdb_init(int level);
+extern noinline void kgdb_breakpoint(void);
+
+#undef pr_debug
+#if 0
+#define pr_debug(a, b...) do { printk(a, ##b); } while(0)
+#else
+#define pr_debug(a, b...) do { } while(0)
+#endif
+
+/* Multipliers for offsets within the PTEs */
+#define PTE_LEVEL_MULT (PAGE_SIZE)
+#define PMD_LEVEL_MULT (PTRS_PER_PTE * PTE_LEVEL_MULT)
+#define PUD_LEVEL_MULT (PTRS_PER_PMD * PMD_LEVEL_MULT)
+#define PGD_LEVEL_MULT (PTRS_PER_PUD * PUD_LEVEL_MULT)
+
+/*
+ * This function gets called on a break in a continuous series
+ * of PTE entries; the next one is different so we need to
+ * print what we collected so far.
+ */
+static void note_page(void *addr)
+{
+    static struct page *lastpage;
+    struct page *page;
+
+    page = virt_to_page(addr);
+
+    if (page != lastpage) {
+        unsigned int level;
+        pte_t *pte = lookup_address((unsigned long) addr, &level);
+        struct page *pt_page2 = pte_page(*pte);
+        //debug("Note page %p (=> %p => %p|%ld).\n", addr, pte, pt_page2, page_to_pfn(pt_page2));
+        SetPageTOI_Untracked(pt_page2);
+        lastpage = page;
+    }
+}
+
+static void walk_pte_level(pmd_t addr)
+{
+        int i;
+        pte_t *start;
+
+        start = (pte_t *) pmd_page_vaddr(addr);
+        for (i = 0; i < PTRS_PER_PTE; i++) {
+                note_page(start);
+                start++;
+        }
+}
+
+#if PTRS_PER_PMD > 1
+
+static void walk_pmd_level(pud_t addr)
+{
+        int i;
+        pmd_t *start;
+
+        start = (pmd_t *) pud_page_vaddr(addr);
+        for (i = 0; i < PTRS_PER_PMD; i++) {
+                if (!pmd_none(*start)) {
+                        if (pmd_large(*start) || !pmd_present(*start))
+                                note_page(start);
+                        else
+                                walk_pte_level(*start);
+                } else
+                        note_page(start);
+                start++;
+        }
+}
+
+#else
+#define walk_pmd_level(a) walk_pte_level(__pmd(pud_val(a)))
+#define pud_large(a) pmd_large(__pmd(pud_val(a)))
+#define pud_none(a)  pmd_none(__pmd(pud_val(a)))
+#endif
+
+#if PTRS_PER_PUD > 1
+
+static void walk_pud_level(pgd_t addr)
+{
+        int i;
+        pud_t *start;
+
+        start = (pud_t *) pgd_page_vaddr(addr);
+
+        for (i = 0; i < PTRS_PER_PUD; i++) {
+                if (!pud_none(*start)) {
+                        if (pud_large(*start) || !pud_present(*start))
+                                note_page(start);
+                        else
+                                walk_pmd_level(*start);
+                } else
+                        note_page(start);
+
+                start++;
+        }
+}
+
+#else
+#define walk_pud_level(a) walk_pmd_level(__pud(pgd_val(a)))
+#define pgd_large(a) pud_large(__pud(pgd_val(a)))
+#define pgd_none(a)  pud_none(__pud(pgd_val(a)))
+#endif
+
+/*
+ * Not static in the original at the time of writing, so needs renaming here.
+ */
+static void toi_ptdump_walk_pgd_level(pgd_t *pgd)
+{
+#ifdef CONFIG_X86_64
+        pgd_t *start = (pgd_t *) &init_level4_pgt;
+#else
+        pgd_t *start = swapper_pg_dir;
+#endif
+        int i;
+        if (pgd) {
+                start = pgd;
+        }
+
+        for (i = 0; i < PTRS_PER_PGD; i++) {
+                if (!pgd_none(*start)) {
+                        if (pgd_large(*start) || !pgd_present(*start))
+                                note_page(start);
+                        else
+                                walk_pud_level(*start);
+                } else
+                        note_page(start);
+
+                start++;
+        }
+
+        /* Flush out the last page */
+        note_page(start);
+}
+
+#ifdef CONFIG_PARAVIRT
+extern struct pv_info pv_info;
+
+static void toi_set_paravirt_ops_untracked(void) {
+    int i;
+
+    unsigned long pvpfn = page_to_pfn(virt_to_page(__parainstructions)),
+                  pvpfn_end = page_to_pfn(virt_to_page(__parainstructions_end));
+    //debug(KERN_EMERG ".parainstructions goes from pfn %ld to %ld.\n", pvpfn, pvpfn_end);
+    for (i = pvpfn; i <= pvpfn_end; i++) {
+        SetPageTOI_Untracked(pfn_to_page(i));
+    }
+}
+#else
+#define toi_set_paravirt_ops_untracked() { do { } while(0) }
+#endif
+
+extern void toi_mark_per_cpus_pages_untracked(void);
+
+void toi_untrack_stack(unsigned long *stack)
+{
+    int i;
+    struct page *stack_page = virt_to_page(stack);
+
+    for (i = 0; i < (1 << THREAD_SIZE_ORDER); i++) {
+        pr_debug("Untrack stack page %p.\n", page_address(stack_page + i));
+        SetPageTOI_Untracked(stack_page + i);
+    }
+}
+void toi_untrack_process(struct task_struct *p)
+{
+    SetPageTOI_Untracked(virt_to_page(p));
+    pr_debug("Untrack process %d page %p.\n", p->pid, page_address(virt_to_page(p)));
+
+    toi_untrack_stack(p->stack);
+}
+
+void toi_generate_untracked_map(void)
+{
+    struct task_struct *p, *t;
+    struct page *page;
+    pte_t *pte;
+    int i;
+    unsigned int level;
+    static int been_here = 0;
+
+    if (been_here)
+        return;
+
+    been_here = 1;
+
+    /* Pagetable pages */
+    toi_ptdump_walk_pgd_level(NULL);
+
+    /* Printk buffer - not normally needed but can be helpful for debugging. */
+    //toi_set_logbuf_untracked();
+
+    /* Paravirt ops */
+    toi_set_paravirt_ops_untracked();
+
+    /* Task structs and stacks */
+    for_each_process_thread(p, t) {
+        toi_untrack_process(p);
+        //toi_untrack_stack((unsigned long *) t->thread.sp);
+    }
+
+    for (i = 0; i < NR_CPUS; i++) {
+        struct task_struct *idle = idle_task(i);
+
+        if (idle) {
+            pr_debug("Untrack idle process for CPU %d.\n", i);
+            toi_untrack_process(idle);
+        }
+
+        /* IRQ stack */
+        pr_debug("Untrack IRQ stack for CPU %d.\n", i);
+        toi_untrack_stack((unsigned long *)per_cpu(irq_stack_ptr, i));
+    }
+
+    /* Per CPU data */
+    //pr_debug("Untracking per CPU variable pages.\n");
+    toi_mark_per_cpus_pages_untracked();
+
+    /* Init stack - for bringing up secondary CPUs */
+    page = virt_to_page(init_stack);
+    for (i = 0; i < DIV_ROUND_UP(sizeof(init_stack), PAGE_SIZE); i++) {
+        SetPageTOI_Untracked(page + i);
+    }
+
+    pte = lookup_address((unsigned long) &mmu_cr4_features, &level);
+    SetPageTOI_Untracked(pte_page(*pte));
+    SetPageTOI_Untracked(virt_to_page(trampoline_cr4_features));
+}
+
+/**
+ * toi_reset_dirtiness_one
+ */
+
+void toi_reset_dirtiness_one(unsigned long pfn, int verbose)
+{
+    struct page *page = pfn_to_page(pfn);
+
+    /**
+     * Don't worry about whether the Dirty flag is
+     * already set. If this is our first call, it
+     * won't be.
+     */
+
+    preempt_disable();
+
+    ClearPageTOI_Dirty(page);
+    SetPageTOI_RO(page);
+    if (verbose)
+        printk(KERN_EMERG "Making page %ld (%p|%p) read only.\n", pfn, page, page_address(page));
+
+    set_memory_ro((unsigned long) page_address(page), 1);
+
+    preempt_enable();
+}
+
+/**
+ * TuxOnIce's incremental image support works by marking all memory apart from
+ * the page tables read-only, then in the page-faults that result enabling
+ * writing if appropriate and flagging the page as dirty. Free pages are also
+ * marked as dirty and not protected so that if allocated, they will be included
+ * in the image without further processing.
+ *
+ * toi_reset_dirtiness is called when and image exists and incremental images are
+ * enabled, and each time we resume thereafter. It is not invoked on a fresh boot.
+ *
+ * This routine should be called from a single-cpu-running context to avoid races in setting
+ * page dirty/read only flags.
+ *
+ * TODO: Make "it is not invoked on a fresh boot" true  when I've finished developing it!
+ *
+ * TODO: Consider Xen paravirt guest boot issues. See arch/x86/mm/pageattr.c.
+ **/
+
+int toi_reset_dirtiness(int verbose)
+{
+        struct zone *zone;
+        unsigned long loop;
+        int allocated_map = 0;
+
+        toi_generate_untracked_map();
+
+        if (!free_map) {
+            if (!toi_alloc_bitmap(&free_map))
+                return -ENOMEM;
+            allocated_map = 1;
+        }
+
+        toi_generate_free_page_map();
+
+        pr_debug(KERN_EMERG "Reset dirtiness.\n");
+        for_each_populated_zone(zone) {
+            // 64 bit only. No need to worry about highmem.
+            for (loop = 0; loop < zone->spanned_pages; loop++) {
+                unsigned long pfn = zone->zone_start_pfn + loop;
+                struct page *page;
+                int chunk_size;
+
+                if (!pfn_valid(pfn)) {
+                    continue;
+                }
+
+                chunk_size = toi_size_of_free_region(zone, pfn);
+                if (chunk_size) {
+                    loop += chunk_size - 1;
+                    continue;
+                }
+
+                page = pfn_to_page(pfn);
+
+                if (PageNosave(page) || !saveable_page(zone, pfn)) {
+                    continue;
+                }
+
+                if (PageTOI_Untracked(page)) {
+                    continue;
+                }
+
+                /**
+                 * Do we need to (re)protect the page?
+                 * If it is already protected (PageTOI_RO), there is
+                 * nothing to do - skip the following.
+                 * If it is marked as dirty (PageTOI_Dirty), it was
+                 * either free and has been allocated or has been
+                 * written to and marked dirty. Reset the dirty flag
+                 * and (re)apply the protection.
+                 */
+                if (!PageTOI_RO(page)) {
+                    toi_reset_dirtiness_one(pfn, verbose);
+                }
+            }
+        }
+
+        pr_debug(KERN_EMERG "Done resetting dirtiness.\n");
+
+        if (allocated_map) {
+            toi_free_bitmap(&free_map);
+        }
+        return 0;
+}
+
+static int toi_reset_dirtiness_initcall(void)
+{
+    if (toi_do_incremental_initcall) {
+        pr_info("TuxOnIce: Enabling dirty page tracking.\n");
+        toi_reset_dirtiness(0);
+    }
+    return 1;
+}
+extern void toi_generate_untracked_map(void);
+
+// Leave early_initcall for pages to register untracked sections.
+early_initcall(toi_reset_dirtiness_initcall);
+
+static int __init toi_incremental_initcall_setup(char *str)
+{
+        int value;
+
+        if (sscanf(str, "=%d", &value) && value)
+                toi_do_incremental_initcall = value;
+
+        return 1;
+}
+__setup("toi_incremental_initcall", toi_incremental_initcall_setup);
diff --git a/kernel/power/tuxonice_io.c b/kernel/power/tuxonice_io.c
new file mode 100644
index 000000000..3c62c2682
--- /dev/null
+++ b/kernel/power/tuxonice_io.c
@@ -0,0 +1,1932 @@
+/*
+ * kernel/power/tuxonice_io.c
+ *
+ * Copyright (C) 1998-2001 Gabor Kuti <seasons@fornax.hu>
+ * Copyright (C) 1998,2001,2002 Pavel Machek <pavel@suse.cz>
+ * Copyright (C) 2002-2003 Florent Chabaud <fchabaud@free.fr>
+ * Copyright (C) 2002-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * It contains high level IO routines for hibernating.
+ *
+ */
+
+#include <linux/suspend.h>
+#include <linux/version.h>
+#include <linux/utsname.h>
+#include <linux/mount.h>
+#include <linux/highmem.h>
+#include <linux/kthread.h>
+#include <linux/cpu.h>
+#include <linux/fs_struct.h>
+#include <linux/bio.h>
+#include <linux/fs_uuid.h>
+#include <linux/kmod.h>
+#include <asm/tlbflush.h>
+
+#include "tuxonice.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_pageflags.h"
+#include "tuxonice_io.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_storage.h"
+#include "tuxonice_prepare_image.h"
+#include "tuxonice_extent.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice_builtin.h"
+#include "tuxonice_checksum.h"
+#include "tuxonice_alloc.h"
+char alt_resume_param[256];
+
+/* Version read from image header at resume */
+static int toi_image_header_version;
+
+#define read_if_version(VERS, VAR, DESC, ERR_ACT) do {                                        \
+        if (likely(toi_image_header_version >= VERS))                                \
+                if (toiActiveAllocator->rw_header_chunk(READ, NULL,                \
+                                        (char *) &VAR, sizeof(VAR))) {                \
+                        abort_hibernate(TOI_FAILED_IO, "Failed to read DESC.");        \
+                        ERR_ACT;                                        \
+                }                                                                \
+} while(0)                                                                        \
+
+/* Variables shared between threads and updated under the mutex */
+static int io_write, io_finish_at, io_base, io_barmax, io_pageset, io_result;
+static int io_index, io_nextupdate, io_pc, io_pc_step;
+static DEFINE_MUTEX(io_mutex);
+static DEFINE_PER_CPU(struct page *, last_sought);
+static DEFINE_PER_CPU(struct page *, last_high_page);
+static DEFINE_PER_CPU(char *, checksum_locn);
+static DEFINE_PER_CPU(struct pbe *, last_low_page);
+static atomic_t io_count;
+atomic_t toi_io_workers;
+
+static int using_flusher;
+
+DECLARE_WAIT_QUEUE_HEAD(toi_io_queue_flusher);
+
+int toi_bio_queue_flusher_should_finish;
+
+int toi_max_workers;
+
+static char *image_version_error = "The image header version is newer than " \
+        "this kernel supports.";
+
+struct toi_module_ops *first_filter;
+
+static atomic_t toi_num_other_threads;
+static DECLARE_WAIT_QUEUE_HEAD(toi_worker_wait_queue);
+enum toi_worker_commands {
+        TOI_IO_WORKER_STOP,
+        TOI_IO_WORKER_RUN,
+        TOI_IO_WORKER_EXIT
+};
+static enum toi_worker_commands toi_worker_command;
+
+/**
+ * toi_attempt_to_parse_resume_device - determine if we can hibernate
+ *
+ * Can we hibernate, using the current resume= parameter?
+ **/
+int toi_attempt_to_parse_resume_device(int quiet)
+{
+        struct list_head *Allocator;
+        struct toi_module_ops *thisAllocator;
+        int result, returning = 0;
+
+        if (toi_activate_storage(0))
+                return 0;
+
+        toiActiveAllocator = NULL;
+        clear_toi_state(TOI_RESUME_DEVICE_OK);
+        clear_toi_state(TOI_CAN_RESUME);
+        clear_result_state(TOI_ABORTED);
+
+        if (!toiNumAllocators) {
+                if (!quiet)
+                        printk(KERN_INFO "TuxOnIce: No storage allocators have "
+                                "been registered. Hibernating will be "
+                                "disabled.\n");
+                goto cleanup;
+        }
+
+        list_for_each(Allocator, &toiAllocators) {
+                thisAllocator = list_entry(Allocator, struct toi_module_ops,
+                                                                type_list);
+
+                /*
+                 * Not sure why you'd want to disable an allocator, but
+                 * we should honour the flag if we're providing it
+                 */
+                if (!thisAllocator->enabled)
+                        continue;
+
+                result = thisAllocator->parse_sig_location(
+                                resume_file, (toiNumAllocators == 1),
+                                quiet);
+
+                switch (result) {
+                case -EINVAL:
+                        /* For this allocator, but not a valid
+                         * configuration. Error already printed. */
+                        goto cleanup;
+
+                case 0:
+                        /* For this allocator and valid. */
+                        toiActiveAllocator = thisAllocator;
+
+                        set_toi_state(TOI_RESUME_DEVICE_OK);
+                        set_toi_state(TOI_CAN_RESUME);
+                        returning = 1;
+                        goto cleanup;
+                }
+        }
+        if (!quiet)
+                printk(KERN_INFO "TuxOnIce: No matching enabled allocator "
+                                "found. Resuming disabled.\n");
+cleanup:
+        toi_deactivate_storage(0);
+        return returning;
+}
+
+void attempt_to_parse_resume_device2(void)
+{
+        toi_prepare_usm();
+        toi_attempt_to_parse_resume_device(0);
+        toi_cleanup_usm();
+}
+
+void save_restore_alt_param(int replace, int quiet)
+{
+        static char resume_param_save[255];
+        static unsigned long toi_state_save;
+
+        if (replace) {
+                toi_state_save = toi_state;
+                strcpy(resume_param_save, resume_file);
+                strcpy(resume_file, alt_resume_param);
+        } else {
+                strcpy(resume_file, resume_param_save);
+                toi_state = toi_state_save;
+        }
+        toi_attempt_to_parse_resume_device(quiet);
+}
+
+void attempt_to_parse_alt_resume_param(void)
+{
+        int ok = 0;
+
+        /* Temporarily set resume_param to the poweroff value */
+        if (!strlen(alt_resume_param))
+                return;
+
+        printk(KERN_INFO "=== Trying Poweroff Resume2 ===\n");
+        save_restore_alt_param(SAVE, NOQUIET);
+        if (test_toi_state(TOI_CAN_RESUME))
+                ok = 1;
+
+        printk(KERN_INFO "=== Done ===\n");
+        save_restore_alt_param(RESTORE, QUIET);
+
+        /* If not ok, clear the string */
+        if (ok)
+                return;
+
+        printk(KERN_INFO "Can't resume from that location; clearing "
+                        "alt_resume_param.\n");
+        alt_resume_param[0] = '\0';
+}
+
+/**
+ * noresume_reset_modules - reset data structures in case of non resuming
+ *
+ * When we read the start of an image, modules (and especially the
+ * active allocator) might need to reset data structures if we
+ * decide to remove the image rather than resuming from it.
+ **/
+static void noresume_reset_modules(void)
+{
+        struct toi_module_ops *this_filter;
+
+        list_for_each_entry(this_filter, &toi_filters, type_list)
+                if (this_filter->noresume_reset)
+                        this_filter->noresume_reset();
+
+        if (toiActiveAllocator && toiActiveAllocator->noresume_reset)
+                toiActiveAllocator->noresume_reset();
+}
+
+/**
+ * fill_toi_header - fill the hibernate header structure
+ * @struct toi_header: Header data structure to be filled.
+ **/
+static int fill_toi_header(struct toi_header *sh)
+{
+        int i, error;
+
+        error = init_header((struct swsusp_info *) sh);
+        if (error)
+                return error;
+
+        sh->pagedir = pagedir1;
+        sh->pageset_2_size = pagedir2.size;
+        sh->param0 = toi_result;
+        sh->param1 = toi_bkd.toi_action;
+        sh->param2 = toi_bkd.toi_debug_state;
+        sh->param3 = toi_bkd.toi_default_console_level;
+        sh->root_fs = current->fs->root.mnt->mnt_sb->s_dev;
+        for (i = 0; i < 4; i++)
+                sh->io_time[i/2][i%2] = toi_bkd.toi_io_time[i/2][i%2];
+        sh->bkd = boot_kernel_data_buffer;
+        return 0;
+}
+
+/**
+ * rw_init_modules - initialize modules
+ * @rw:                Whether we are reading of writing an image.
+ * @which:        Section of the image being processed.
+ *
+ * Iterate over modules, preparing the ones that will be used to read or write
+ * data.
+ **/
+static int rw_init_modules(int rw, int which)
+{
+        struct toi_module_ops *this_module;
+        /* Initialise page transformers */
+        list_for_each_entry(this_module, &toi_filters, type_list) {
+                if (!this_module->enabled)
+                        continue;
+                if (this_module->rw_init && this_module->rw_init(rw, which)) {
+                        abort_hibernate(TOI_FAILED_MODULE_INIT,
+                                "Failed to initialize the %s filter.",
+                                this_module->name);
+                        return 1;
+                }
+        }
+
+        /* Initialise allocator */
+        if (toiActiveAllocator->rw_init(rw, which)) {
+                abort_hibernate(TOI_FAILED_MODULE_INIT,
+                                "Failed to initialise the allocator.");
+                return 1;
+        }
+
+        /* Initialise other modules */
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                if (!this_module->enabled ||
+                    this_module->type == FILTER_MODULE ||
+                    this_module->type == WRITER_MODULE)
+                        continue;
+                if (this_module->rw_init && this_module->rw_init(rw, which)) {
+                        set_abort_result(TOI_FAILED_MODULE_INIT);
+                        printk(KERN_INFO "Setting aborted flag due to module "
+                                        "init failure.\n");
+                        return 1;
+                }
+        }
+
+        return 0;
+}
+
+/**
+ * rw_cleanup_modules - cleanup modules
+ * @rw:        Whether we are reading of writing an image.
+ *
+ * Cleanup components after reading or writing a set of pages.
+ * Only the allocator may fail.
+ **/
+static int rw_cleanup_modules(int rw)
+{
+        struct toi_module_ops *this_module;
+        int result = 0;
+
+        /* Cleanup other modules */
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                if (!this_module->enabled ||
+                    this_module->type == FILTER_MODULE ||
+                    this_module->type == WRITER_MODULE)
+                        continue;
+                if (this_module->rw_cleanup)
+                        result |= this_module->rw_cleanup(rw);
+        }
+
+        /* Flush data and cleanup */
+        list_for_each_entry(this_module, &toi_filters, type_list) {
+                if (!this_module->enabled)
+                        continue;
+                if (this_module->rw_cleanup)
+                        result |= this_module->rw_cleanup(rw);
+        }
+
+        result |= toiActiveAllocator->rw_cleanup(rw);
+
+        return result;
+}
+
+static struct page *copy_page_from_orig_page(struct page *orig_page, int is_high)
+{
+        int index, min, max;
+        struct page *high_page = NULL,
+                    **my_last_high_page = raw_cpu_ptr(&last_high_page),
+                    **my_last_sought = raw_cpu_ptr(&last_sought);
+        struct pbe *this, **my_last_low_page = raw_cpu_ptr(&last_low_page);
+        void *compare;
+
+        if (is_high) {
+                if (*my_last_sought && *my_last_high_page &&
+                                *my_last_sought < orig_page)
+                        high_page = *my_last_high_page;
+                else
+                        high_page = (struct page *) restore_highmem_pblist;
+                this = (struct pbe *) kmap(high_page);
+                compare = orig_page;
+        } else {
+                if (*my_last_sought && *my_last_low_page &&
+                                *my_last_sought < orig_page)
+                        this = *my_last_low_page;
+                else
+                        this = restore_pblist;
+                compare = page_address(orig_page);
+        }
+
+        *my_last_sought = orig_page;
+
+        /* Locate page containing pbe */
+        while (this[PBES_PER_PAGE - 1].next &&
+                        this[PBES_PER_PAGE - 1].orig_address < compare) {
+                if (is_high) {
+                        struct page *next_high_page = (struct page *)
+                                this[PBES_PER_PAGE - 1].next;
+                        kunmap(high_page);
+                        this = kmap(next_high_page);
+                        high_page = next_high_page;
+                } else
+                        this = this[PBES_PER_PAGE - 1].next;
+        }
+
+        /* Do a binary search within the page */
+        min = 0;
+        max = PBES_PER_PAGE;
+        index = PBES_PER_PAGE / 2;
+        while (max - min) {
+                if (!this[index].orig_address ||
+                    this[index].orig_address > compare)
+                        max = index;
+                else if (this[index].orig_address == compare) {
+                        if (is_high) {
+                                struct page *page = this[index].address;
+                                *my_last_high_page = high_page;
+                                kunmap(high_page);
+                                return page;
+                        }
+                        *my_last_low_page = this;
+                        return virt_to_page(this[index].address);
+                } else
+                        min = index;
+                index = ((max + min) / 2);
+        };
+
+        if (is_high)
+                kunmap(high_page);
+
+        abort_hibernate(TOI_FAILED_IO, "Failed to get destination page for"
+                " orig page %p. This[min].orig_address=%p.\n", orig_page,
+                this[index].orig_address);
+        return NULL;
+}
+
+/**
+ * write_next_page - write the next page in a pageset
+ * @data_pfn: The pfn where the next data to write is located.
+ * @my_io_index: The index of the page in the pageset.
+ * @write_pfn: The pfn number to write in the image (where the data belongs).
+ *
+ * Get the pfn of the next page to write, map the page if necessary and do the
+ * write.
+ **/
+static int write_next_page(unsigned long *data_pfn, int *my_io_index,
+                unsigned long *write_pfn)
+{
+        struct page *page;
+        char **my_checksum_locn = raw_cpu_ptr(&checksum_locn);
+        int result = 0, was_present;
+
+        *data_pfn = memory_bm_next_pfn(io_map, 0);
+
+        /* Another thread could have beaten us to it. */
+        if (*data_pfn == BM_END_OF_MAP) {
+                if (atomic_read(&io_count)) {
+                        printk(KERN_INFO "Ran out of pfns but io_count is "
+                                        "still %d.\n", atomic_read(&io_count));
+                        BUG();
+                }
+                mutex_unlock(&io_mutex);
+                return -ENODATA;
+        }
+
+        *my_io_index = io_finish_at - atomic_sub_return(1, &io_count);
+
+        memory_bm_clear_bit(io_map, 0, *data_pfn);
+        page = pfn_to_page(*data_pfn);
+
+        was_present = kernel_page_present(page);
+        if (!was_present)
+                kernel_map_pages(page, 1, 1);
+
+        if (io_pageset == 1)
+                *write_pfn = memory_bm_next_pfn(pageset1_map, 0);
+        else {
+                *write_pfn = *data_pfn;
+                *my_checksum_locn = tuxonice_get_next_checksum();
+        }
+
+        TOI_TRACE_DEBUG(*data_pfn, "_PS%d_write %d", io_pageset, *my_io_index);
+
+        mutex_unlock(&io_mutex);
+
+        if (io_pageset == 2 && tuxonice_calc_checksum(page, *my_checksum_locn))
+                return 1;
+
+        result = first_filter->write_page(*write_pfn, TOI_PAGE, page,
+                        PAGE_SIZE);
+
+        if (!was_present)
+                kernel_map_pages(page, 1, 0);
+
+        return result;
+}
+
+/**
+ * read_next_page - read the next page in a pageset
+ * @my_io_index: The index of the page in the pageset.
+ * @write_pfn: The pfn in which the data belongs.
+ *
+ * Read a page of the image into our buffer. It can happen (here and in the
+ * write routine) that threads don't get run until after other CPUs have done
+ * all the work. This was the cause of the long standing issue with
+ * occasionally getting -ENODATA errors at the end of reading the image. We
+ * therefore need to check there's actually a page to read before trying to
+ * retrieve one.
+ **/
+
+static int read_next_page(int *my_io_index, unsigned long *write_pfn,
+                struct page *buffer)
+{
+        unsigned int buf_size = PAGE_SIZE;
+        unsigned long left = atomic_read(&io_count);
+
+        if (!left)
+                return -ENODATA;
+
+        /* Start off assuming the page we read isn't resaved */
+        *my_io_index = io_finish_at - atomic_sub_return(1, &io_count);
+
+        mutex_unlock(&io_mutex);
+
+        /*
+         * Are we aborting? If so, don't submit any more I/O as
+         * resetting the resume_attempted flag (from ui.c) will
+         * clear the bdev flags, making this thread oops.
+         */
+        if (unlikely(test_toi_state(TOI_STOP_RESUME))) {
+                atomic_dec(&toi_io_workers);
+                if (!atomic_read(&toi_io_workers)) {
+                        /*
+                         * So we can be sure we'll have memory for
+                         * marking that we haven't resumed.
+                         */
+                        rw_cleanup_modules(READ);
+                        set_toi_state(TOI_IO_STOPPED);
+                }
+                while (1)
+                        schedule();
+        }
+
+        /*
+         * See toi_bio_read_page in tuxonice_bio.c:
+         * read the next page in the image.
+         */
+        return first_filter->read_page(write_pfn, TOI_PAGE, buffer, &buf_size);
+}
+
+static void use_read_page(unsigned long write_pfn, struct page *buffer)
+{
+        struct page *final_page = pfn_to_page(write_pfn),
+                    *copy_page = final_page;
+        char *virt, *buffer_virt;
+        int was_present, cpu = smp_processor_id();
+        unsigned long idx = 0;
+
+        if (io_pageset == 1 && (!pageset1_copy_map ||
+                        !memory_bm_test_bit(pageset1_copy_map, cpu, write_pfn))) {
+                int is_high = PageHighMem(final_page);
+                copy_page = copy_page_from_orig_page(is_high ? (void *) write_pfn : final_page, is_high);
+        }
+
+        if (!memory_bm_test_bit(io_map, cpu, write_pfn)) {
+                int test = !memory_bm_test_bit(io_map, cpu, write_pfn);
+                toi_message(TOI_IO, TOI_VERBOSE, 0, "Discard %ld (%d).", write_pfn, test);
+                mutex_lock(&io_mutex);
+                idx = atomic_add_return(1, &io_count);
+                mutex_unlock(&io_mutex);
+                return;
+        }
+
+        virt = kmap(copy_page);
+        buffer_virt = kmap(buffer);
+        was_present = kernel_page_present(copy_page);
+        if (!was_present)
+                kernel_map_pages(copy_page, 1, 1);
+        memcpy(virt, buffer_virt, PAGE_SIZE);
+        if (!was_present)
+                kernel_map_pages(copy_page, 1, 0);
+        kunmap(copy_page);
+        kunmap(buffer);
+        memory_bm_clear_bit(io_map, cpu, write_pfn);
+        TOI_TRACE_DEBUG(write_pfn, "_PS%d_read", io_pageset);
+}
+
+static unsigned long status_update(int writing, unsigned long done,
+                unsigned long ticks)
+{
+        int cs_index = writing ? 0 : 1;
+        unsigned long ticks_so_far = toi_bkd.toi_io_time[cs_index][1] + ticks;
+        unsigned long msec = jiffies_to_msecs(abs(ticks_so_far));
+        unsigned long pgs_per_s, estimate = 0, pages_left;
+
+        if (msec) {
+                pages_left = io_barmax - done;
+                pgs_per_s = 1000 * done / msec;
+                if (pgs_per_s)
+                        estimate = DIV_ROUND_UP(pages_left, pgs_per_s);
+        }
+
+        if (estimate && ticks > HZ / 2)
+                return toi_update_status(done, io_barmax,
+                        " %d/%d MB (%lu sec left)",
+                        MB(done+1), MB(io_barmax), estimate);
+
+        return toi_update_status(done, io_barmax, " %d/%d MB",
+                MB(done+1), MB(io_barmax));
+}
+
+/**
+ * worker_rw_loop - main loop to read/write pages
+ *
+ * The main I/O loop for reading or writing pages. The io_map bitmap is used to
+ * track the pages to read/write.
+ * If we are reading, the pages are loaded to their final (mapped) pfn.
+ * Data is non zero iff this is a thread started via start_other_threads.
+ * In that case, we stay in here until told to quit.
+ **/
+static int worker_rw_loop(void *data)
+{
+        unsigned long data_pfn, write_pfn, next_jiffies = jiffies + HZ / 4,
+                      jif_index = 1, start_time = jiffies, thread_num;
+        int result = 0, my_io_index = 0, last_worker;
+        struct page *buffer = toi_alloc_page(28, TOI_ATOMIC_GFP);
+        cpumask_var_t orig_mask;
+
+        if (!alloc_cpumask_var(&orig_mask, GFP_KERNEL)) {
+                printk(KERN_EMERG "Failed to allocate cpumask for TuxOnIce I/O thread %ld.\n", (unsigned long) data);
+                result = -ENOMEM;
+                goto out;
+        }
+
+        cpumask_copy(orig_mask, tsk_cpus_allowed(current));
+
+        current->flags |= PF_NOFREEZE;
+
+top:
+        mutex_lock(&io_mutex);
+        thread_num = atomic_read(&toi_io_workers);
+
+        cpumask_copy(tsk_cpus_allowed(current), orig_mask);
+        schedule();
+
+        atomic_inc(&toi_io_workers);
+
+        while (atomic_read(&io_count) >= atomic_read(&toi_io_workers) &&
+                !(io_write && test_result_state(TOI_ABORTED)) &&
+                toi_worker_command == TOI_IO_WORKER_RUN) {
+                if (!thread_num && jiffies > next_jiffies) {
+                        next_jiffies += HZ / 4;
+                        if (toiActiveAllocator->update_throughput_throttle)
+                                toiActiveAllocator->update_throughput_throttle(
+                                                jif_index);
+                        jif_index++;
+                }
+
+                /*
+                 * What page to use? If reading, don't know yet which page's
+                 * data will be read, so always use the buffer. If writing,
+                 * use the copy (Pageset1) or original page (Pageset2), but
+                 * always write the pfn of the original page.
+                 */
+                if (io_write)
+                        result = write_next_page(&data_pfn, &my_io_index,
+                                        &write_pfn);
+                else /* Reading */
+                        result = read_next_page(&my_io_index, &write_pfn,
+                                        buffer);
+
+                if (result) {
+                        mutex_lock(&io_mutex);
+                        /* Nothing to do? */
+                        if (result == -ENODATA) {
+                                toi_message(TOI_IO, TOI_VERBOSE, 0,
+                                        "Thread %d has no more work.",
+                                        smp_processor_id());
+                                break;
+                        }
+
+                        io_result = result;
+
+                        if (io_write) {
+                                printk(KERN_INFO "Write chunk returned %d.\n",
+                                                result);
+                                abort_hibernate(TOI_FAILED_IO,
+                                        "Failed to write a chunk of the "
+                                        "image.");
+                                break;
+                        }
+
+                        if (io_pageset == 1) {
+                                printk(KERN_ERR "\nBreaking out of I/O loop "
+                                        "because of result code %d.\n", result);
+                                break;
+                        }
+                        panic("Read chunk returned (%d)", result);
+                }
+
+                /*
+                 * Discard reads of resaved pages while reading ps2
+                 * and unwanted pages while rereading ps2 when aborting.
+                 */
+                if (!io_write) {
+                        if (!PageResave(pfn_to_page(write_pfn)))
+                                use_read_page(write_pfn, buffer);
+                        else {
+                                mutex_lock(&io_mutex);
+                                toi_message(TOI_IO, TOI_VERBOSE, 0,
+                                                "Resaved %ld.", write_pfn);
+                                atomic_inc(&io_count);
+                                mutex_unlock(&io_mutex);
+                        }
+                }
+
+                if (!thread_num) {
+                        if(my_io_index + io_base > io_nextupdate)
+                                io_nextupdate = status_update(io_write,
+                                                my_io_index + io_base,
+                                                jiffies - start_time);
+
+                        if (my_io_index > io_pc) {
+                                printk(KERN_CONT "...%d%%", 20 * io_pc_step);
+                                io_pc_step++;
+                                io_pc = io_finish_at * io_pc_step / 5;
+                        }
+                }
+
+                toi_cond_pause(0, NULL);
+
+                /*
+                 * Subtle: If there's less I/O still to be done than threads
+                 * running, quit. This stops us doing I/O beyond the end of
+                 * the image when reading.
+                 *
+                 * Possible race condition. Two threads could do the test at
+                 * the same time; one should exit and one should continue.
+                 * Therefore we take the mutex before comparing and exiting.
+                 */
+
+                mutex_lock(&io_mutex);
+        }
+
+        last_worker = atomic_dec_and_test(&toi_io_workers);
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "%d workers left.", atomic_read(&toi_io_workers));
+        mutex_unlock(&io_mutex);
+
+        if ((unsigned long) data && toi_worker_command != TOI_IO_WORKER_EXIT) {
+                /* Were we the last thread and we're using a flusher thread? */
+                if (last_worker && using_flusher) {
+                        toiActiveAllocator->finish_all_io();
+                }
+                /* First, if we're doing I/O, wait for it to finish */
+                wait_event(toi_worker_wait_queue, toi_worker_command != TOI_IO_WORKER_RUN);
+                /* Then wait to be told what to do next */
+                wait_event(toi_worker_wait_queue, toi_worker_command != TOI_IO_WORKER_STOP);
+                if (toi_worker_command == TOI_IO_WORKER_RUN)
+                        goto top;
+        }
+
+        if (thread_num)
+                atomic_dec(&toi_num_other_threads);
+
+out:
+        toi_message(TOI_IO, TOI_LOW, 0, "Thread %d exiting.", thread_num);
+        toi__free_page(28, buffer);
+        free_cpumask_var(orig_mask);
+
+        return result;
+}
+
+int toi_start_other_threads(void)
+{
+        int cpu;
+        struct task_struct *p;
+        int to_start = (toi_max_workers ? toi_max_workers : num_online_cpus()) - 1;
+  unsigned long num_started = 0;
+
+        if (test_action_state(TOI_NO_MULTITHREADED_IO))
+                return 0;
+
+        toi_worker_command = TOI_IO_WORKER_STOP;
+
+        for_each_online_cpu(cpu) {
+                if (num_started == to_start)
+                        break;
+
+                if (cpu == smp_processor_id())
+                        continue;
+
+                p = kthread_create_on_node(worker_rw_loop, (void *) num_started + 1,
+                                cpu_to_node(cpu), "ktoi_io/%d", cpu);
+                if (IS_ERR(p)) {
+                        printk(KERN_ERR "ktoi_io for %i failed\n", cpu);
+                        continue;
+                }
+                kthread_bind(p, cpu);
+                p->flags |= PF_MEMALLOC;
+                wake_up_process(p);
+                num_started++;
+                atomic_inc(&toi_num_other_threads);
+        }
+
+        toi_message(TOI_IO, TOI_LOW, 0, "Started %d threads.", num_started);
+        return num_started;
+}
+
+void toi_stop_other_threads(void)
+{
+        toi_message(TOI_IO, TOI_LOW, 0, "Stopping other threads.");
+        toi_worker_command = TOI_IO_WORKER_EXIT;
+        wake_up(&toi_worker_wait_queue);
+}
+
+/**
+ * do_rw_loop - main highlevel function for reading or writing pages
+ *
+ * Create the io_map bitmap and call worker_rw_loop to perform I/O operations.
+ **/
+static int do_rw_loop(int write, int finish_at, struct memory_bitmap *pageflags,
+                int base, int barmax, int pageset)
+{
+        int index = 0, cpu, result = 0, workers_started;
+        unsigned long pfn, next;
+
+        first_filter = toi_get_next_filter(NULL);
+
+        if (!finish_at)
+                return 0;
+
+        io_write = write;
+        io_finish_at = finish_at;
+        io_base = base;
+        io_barmax = barmax;
+        io_pageset = pageset;
+        io_index = 0;
+        io_pc = io_finish_at / 5;
+        io_pc_step = 1;
+        io_result = 0;
+        io_nextupdate = base + 1;
+        toi_bio_queue_flusher_should_finish = 0;
+
+        for_each_online_cpu(cpu) {
+                per_cpu(last_sought, cpu) = NULL;
+                per_cpu(last_low_page, cpu) = NULL;
+                per_cpu(last_high_page, cpu) = NULL;
+        }
+
+        /* Ensure all bits clear */
+        memory_bm_clear(io_map);
+
+        memory_bm_position_reset(io_map);
+        next = memory_bm_next_pfn(io_map, 0);
+
+        BUG_ON(next != BM_END_OF_MAP);
+
+        /* Set the bits for the pages to write */
+        memory_bm_position_reset(pageflags);
+
+        pfn = memory_bm_next_pfn(pageflags, 0);
+        toi_trace_index++;
+
+        while (pfn != BM_END_OF_MAP && index < finish_at) {
+                TOI_TRACE_DEBUG(pfn, "_io_pageset_%d (%d/%d)", pageset, index + 1, finish_at);
+                memory_bm_set_bit(io_map, 0, pfn);
+                pfn = memory_bm_next_pfn(pageflags, 0);
+                index++;
+        }
+
+        BUG_ON(next != BM_END_OF_MAP || index < finish_at);
+
+        memory_bm_position_reset(io_map);
+        toi_trace_index++;
+
+        atomic_set(&io_count, finish_at);
+
+        memory_bm_position_reset(pageset1_map);
+
+        mutex_lock(&io_mutex);
+
+        clear_toi_state(TOI_IO_STOPPED);
+
+        using_flusher = (atomic_read(&toi_num_other_threads) &&
+                         toiActiveAllocator->io_flusher &&
+                         !test_action_state(TOI_NO_FLUSHER_THREAD));
+
+        workers_started = atomic_read(&toi_num_other_threads);
+
+        memory_bm_position_reset(io_map);
+        memory_bm_position_reset(pageset1_copy_map);
+
+        toi_worker_command = TOI_IO_WORKER_RUN;
+        wake_up(&toi_worker_wait_queue);
+
+        mutex_unlock(&io_mutex);
+
+        if (using_flusher)
+                result = toiActiveAllocator->io_flusher(write);
+        else
+                worker_rw_loop(NULL);
+
+        while (atomic_read(&toi_io_workers))
+                schedule();
+
+        printk(KERN_CONT "\n");
+
+        toi_worker_command = TOI_IO_WORKER_STOP;
+        wake_up(&toi_worker_wait_queue);
+
+        if (unlikely(test_toi_state(TOI_STOP_RESUME))) {
+                if (!atomic_read(&toi_io_workers)) {
+                        rw_cleanup_modules(READ);
+                        set_toi_state(TOI_IO_STOPPED);
+                }
+                while (1)
+                        schedule();
+        }
+        set_toi_state(TOI_IO_STOPPED);
+
+        if (!io_result && !result && !test_result_state(TOI_ABORTED)) {
+                unsigned long next;
+
+                toi_update_status(io_base + io_finish_at, io_barmax,
+                                " %d/%d MB ",
+                                MB(io_base + io_finish_at), MB(io_barmax));
+
+                memory_bm_position_reset(io_map);
+                next = memory_bm_next_pfn(io_map, 0);
+                if  (next != BM_END_OF_MAP) {
+                        printk(KERN_INFO "Finished I/O loop but still work to "
+                                        "do?\nFinish at = %d. io_count = %d.\n",
+                                        finish_at, atomic_read(&io_count));
+                        printk(KERN_INFO "I/O bitmap still records work to do."
+                                        "%ld.\n", next);
+                        BUG();
+                        do {
+                                cpu_relax();
+                        } while (0);
+                }
+        }
+
+        return io_result ? io_result : result;
+}
+
+/**
+ * write_pageset - write a pageset to disk.
+ * @pagedir:        Which pagedir to write.
+ *
+ * Returns:
+ *        Zero on success or -1 on failure.
+ **/
+int write_pageset(struct pagedir *pagedir)
+{
+        int finish_at, base = 0;
+        int barmax = pagedir1.size + pagedir2.size;
+        long error = 0;
+        struct memory_bitmap *pageflags;
+        unsigned long start_time, end_time;
+
+        /*
+         * Even if there is nothing to read or write, the allocator
+         * may need the init/cleanup for it's housekeeping.  (eg:
+         * Pageset1 may start where pageset2 ends when writing).
+         */
+        finish_at = pagedir->size;
+
+        if (pagedir->id == 1) {
+                toi_prepare_status(DONT_CLEAR_BAR,
+                                "Writing kernel & process data...");
+                base = pagedir2.size;
+                if (test_action_state(TOI_TEST_FILTER_SPEED) ||
+                    test_action_state(TOI_TEST_BIO))
+                        pageflags = pageset1_map;
+                else
+                        pageflags = pageset1_copy_map;
+        } else {
+                toi_prepare_status(DONT_CLEAR_BAR, "Writing caches...");
+                pageflags = pageset2_map;
+        }
+
+        start_time = jiffies;
+
+        if (rw_init_modules(WRITE, pagedir->id)) {
+                abort_hibernate(TOI_FAILED_MODULE_INIT,
+                                "Failed to initialise modules for writing.");
+                error = 1;
+        }
+
+        if (!error)
+                error = do_rw_loop(WRITE, finish_at, pageflags, base, barmax,
+                                pagedir->id);
+
+        if (rw_cleanup_modules(WRITE) && !error) {
+                abort_hibernate(TOI_FAILED_MODULE_CLEANUP,
+                                "Failed to cleanup after writing.");
+                error = 1;
+        }
+
+        end_time = jiffies;
+
+        if ((end_time - start_time) && (!test_result_state(TOI_ABORTED))) {
+                toi_bkd.toi_io_time[0][0] += finish_at,
+                toi_bkd.toi_io_time[0][1] += (end_time - start_time);
+        }
+
+        return error;
+}
+
+/**
+ * read_pageset - highlevel function to read a pageset from disk
+ * @pagedir:                        pageset to read
+ * @overwrittenpagesonly:        Whether to read the whole pageset or
+ *                                only part of it.
+ *
+ * Returns:
+ *        Zero on success or -1 on failure.
+ **/
+static int read_pageset(struct pagedir *pagedir, int overwrittenpagesonly)
+{
+        int result = 0, base = 0;
+        int finish_at = pagedir->size;
+        int barmax = pagedir1.size + pagedir2.size;
+        struct memory_bitmap *pageflags;
+        unsigned long start_time, end_time;
+
+        if (pagedir->id == 1) {
+                toi_prepare_status(DONT_CLEAR_BAR,
+                                "Reading kernel & process data...");
+                pageflags = pageset1_map;
+        } else {
+                toi_prepare_status(DONT_CLEAR_BAR, "Reading caches...");
+                if (overwrittenpagesonly) {
+                        barmax = min(pagedir1.size, pagedir2.size);
+                        finish_at = min(pagedir1.size, pagedir2.size);
+                } else
+                        base = pagedir1.size;
+                pageflags = pageset2_map;
+        }
+
+        start_time = jiffies;
+
+        if (rw_init_modules(READ, pagedir->id)) {
+                toiActiveAllocator->remove_image();
+                result = 1;
+        } else
+                result = do_rw_loop(READ, finish_at, pageflags, base, barmax,
+                                pagedir->id);
+
+        if (rw_cleanup_modules(READ) && !result) {
+                abort_hibernate(TOI_FAILED_MODULE_CLEANUP,
+                                "Failed to cleanup after reading.");
+                result = 1;
+        }
+
+        /* Statistics */
+        end_time = jiffies;
+
+        if ((end_time - start_time) && (!test_result_state(TOI_ABORTED))) {
+                toi_bkd.toi_io_time[1][0] += finish_at,
+                toi_bkd.toi_io_time[1][1] += (end_time - start_time);
+        }
+
+        return result;
+}
+
+/**
+ * write_module_configs - store the modules configuration
+ *
+ * The configuration for each module is stored in the image header.
+ * Returns: Int
+ *        Zero on success, Error value otherwise.
+ **/
+static int write_module_configs(void)
+{
+        struct toi_module_ops *this_module;
+        char *buffer = (char *) toi_get_zeroed_page(22, TOI_ATOMIC_GFP);
+        int len, index = 1;
+        struct toi_module_header toi_module_header;
+
+        if (!buffer) {
+                printk(KERN_INFO "Failed to allocate a buffer for saving "
+                                "module configuration info.\n");
+                return -ENOMEM;
+        }
+
+        /*
+         * We have to know which data goes with which module, so we at
+         * least write a length of zero for a module. Note that we are
+         * also assuming every module's config data takes <= PAGE_SIZE.
+         */
+
+        /* For each module (in registration order) */
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                if (!this_module->enabled || !this_module->storage_needed ||
+                    (this_module->type == WRITER_MODULE &&
+                     toiActiveAllocator != this_module))
+                        continue;
+
+                /* Get the data from the module */
+                len = 0;
+                if (this_module->save_config_info)
+                        len = this_module->save_config_info(buffer);
+
+                /* Save the details of the module */
+                toi_module_header.enabled = this_module->enabled;
+                toi_module_header.type = this_module->type;
+                toi_module_header.index = index++;
+                strncpy(toi_module_header.name, this_module->name,
+                                        sizeof(toi_module_header.name));
+                toiActiveAllocator->rw_header_chunk(WRITE,
+                                this_module,
+                                (char *) &toi_module_header,
+                                sizeof(toi_module_header));
+
+                /* Save the size of the data and any data returned */
+                toiActiveAllocator->rw_header_chunk(WRITE,
+                                this_module,
+                                (char *) &len, sizeof(int));
+                if (len)
+                        toiActiveAllocator->rw_header_chunk(
+                                WRITE, this_module, buffer, len);
+        }
+
+        /* Write a blank header to terminate the list */
+        toi_module_header.name[0] = '\0';
+        toiActiveAllocator->rw_header_chunk(WRITE, NULL,
+                        (char *) &toi_module_header, sizeof(toi_module_header));
+
+        toi_free_page(22, (unsigned long) buffer);
+        return 0;
+}
+
+/**
+ * read_one_module_config - read and configure one module
+ *
+ * Read the configuration for one module, and configure the module
+ * to match if it is loaded.
+ *
+ * Returns: Int
+ *        Zero on success, Error value otherwise.
+ **/
+static int read_one_module_config(struct toi_module_header *header)
+{
+        struct toi_module_ops *this_module;
+        int result, len;
+        char *buffer;
+
+        /* Find the module */
+        this_module = toi_find_module_given_name(header->name);
+
+        if (!this_module) {
+                if (header->enabled) {
+                        toi_early_boot_message(1, TOI_CONTINUE_REQ,
+                                "It looks like we need module %s for reading "
+                                "the image but it hasn't been registered.\n",
+                                header->name);
+                        if (!(test_toi_state(TOI_CONTINUE_REQ)))
+                                return -EINVAL;
+                } else
+                        printk(KERN_INFO "Module %s configuration data found, "
+                                "but the module hasn't registered. Looks like "
+                                "it was disabled, so we're ignoring its data.",
+                                header->name);
+        }
+
+        /* Get the length of the data (if any) */
+        result = toiActiveAllocator->rw_header_chunk(READ, NULL, (char *) &len,
+                        sizeof(int));
+        if (result) {
+                printk(KERN_ERR "Failed to read the length of the module %s's"
+                                " configuration data.\n",
+                                header->name);
+                return -EINVAL;
+        }
+
+        /* Read any data and pass to the module (if we found one) */
+        if (!len)
+                return 0;
+
+        buffer = (char *) toi_get_zeroed_page(23, TOI_ATOMIC_GFP);
+
+        if (!buffer) {
+                printk(KERN_ERR "Failed to allocate a buffer for reloading "
+                                "module configuration info.\n");
+                return -ENOMEM;
+        }
+
+        toiActiveAllocator->rw_header_chunk(READ, NULL, buffer, len);
+
+        if (!this_module)
+                goto out;
+
+        if (!this_module->save_config_info)
+                printk(KERN_ERR "Huh? Module %s appears to have a "
+                                "save_config_info, but not a load_config_info "
+                                "function!\n", this_module->name);
+        else
+                this_module->load_config_info(buffer, len);
+
+        /*
+         * Now move this module to the tail of its lists. This will put it in
+         * order. Any new modules will end up at the top of the lists. They
+         * should have been set to disabled when loaded (people will
+         * normally not edit an initrd to load a new module and then hibernate
+         * without using it!).
+         */
+
+        toi_move_module_tail(this_module);
+
+        this_module->enabled = header->enabled;
+
+out:
+        toi_free_page(23, (unsigned long) buffer);
+        return 0;
+}
+
+/**
+ * read_module_configs - reload module configurations from the image header.
+ *
+ * Returns: Int
+ *        Zero on success or an error code.
+ **/
+static int read_module_configs(void)
+{
+        int result = 0;
+        struct toi_module_header toi_module_header;
+        struct toi_module_ops *this_module;
+
+        /* All modules are initially disabled. That way, if we have a module
+         * loaded now that wasn't loaded when we hibernated, it won't be used
+         * in trying to read the data.
+         */
+        list_for_each_entry(this_module, &toi_modules, module_list)
+                this_module->enabled = 0;
+
+        /* Get the first module header */
+        result = toiActiveAllocator->rw_header_chunk(READ, NULL,
+                        (char *) &toi_module_header,
+                        sizeof(toi_module_header));
+        if (result) {
+                printk(KERN_ERR "Failed to read the next module header.\n");
+                return -EINVAL;
+        }
+
+        /* For each module (in registration order) */
+        while (toi_module_header.name[0]) {
+                result = read_one_module_config(&toi_module_header);
+
+                if (result)
+                        return -EINVAL;
+
+                /* Get the next module header */
+                result = toiActiveAllocator->rw_header_chunk(READ, NULL,
+                                (char *) &toi_module_header,
+                                sizeof(toi_module_header));
+
+                if (result) {
+                        printk(KERN_ERR "Failed to read the next module "
+                                        "header.\n");
+                        return -EINVAL;
+                }
+        }
+
+        return 0;
+}
+
+static inline int save_fs_info(struct fs_info *fs, struct block_device *bdev)
+{
+        return (!fs || IS_ERR(fs) || !fs->last_mount_size) ? 0 : 1;
+}
+
+int fs_info_space_needed(void)
+{
+        const struct super_block *sb;
+        int result = sizeof(int);
+
+        list_for_each_entry(sb, &super_blocks, s_list) {
+                struct fs_info *fs;
+
+                if (!sb->s_bdev)
+                        continue;
+
+                fs = fs_info_from_block_dev(sb->s_bdev);
+                if (save_fs_info(fs, sb->s_bdev))
+                        result += 16 + sizeof(dev_t) + sizeof(int) +
+                                fs->last_mount_size;
+                free_fs_info(fs);
+        }
+        return result;
+}
+
+static int fs_info_num_to_save(void)
+{
+        const struct super_block *sb;
+        int to_save = 0;
+
+        list_for_each_entry(sb, &super_blocks, s_list) {
+                struct fs_info *fs;
+
+                if (!sb->s_bdev)
+                        continue;
+
+                fs = fs_info_from_block_dev(sb->s_bdev);
+                if (save_fs_info(fs, sb->s_bdev))
+                        to_save++;
+                free_fs_info(fs);
+        }
+
+        return to_save;
+}
+
+static int fs_info_save(void)
+{
+        const struct super_block *sb;
+        int to_save = fs_info_num_to_save();
+
+        if (toiActiveAllocator->rw_header_chunk(WRITE, NULL, (char *) &to_save,
+                                sizeof(int))) {
+                abort_hibernate(TOI_FAILED_IO, "Failed to write num fs_info"
+                                " to save.");
+                return -EIO;
+        }
+
+        list_for_each_entry(sb, &super_blocks, s_list) {
+                struct fs_info *fs;
+
+                if (!sb->s_bdev)
+                        continue;
+
+                fs = fs_info_from_block_dev(sb->s_bdev);
+                if (save_fs_info(fs, sb->s_bdev)) {
+                        if (toiActiveAllocator->rw_header_chunk(WRITE, NULL,
+                                        &fs->uuid[0], 16)) {
+                                abort_hibernate(TOI_FAILED_IO, "Failed to "
+                                                "write uuid.");
+                                return -EIO;
+                        }
+                        if (toiActiveAllocator->rw_header_chunk(WRITE, NULL,
+                                        (char *) &fs->dev_t, sizeof(dev_t))) {
+                                abort_hibernate(TOI_FAILED_IO, "Failed to "
+                                                "write dev_t.");
+                                return -EIO;
+                        }
+                        if (toiActiveAllocator->rw_header_chunk(WRITE, NULL,
+                                        (char *) &fs->last_mount_size, sizeof(int))) {
+                                abort_hibernate(TOI_FAILED_IO, "Failed to "
+                                                "write last mount length.");
+                                return -EIO;
+                        }
+                        if (toiActiveAllocator->rw_header_chunk(WRITE, NULL,
+                                        fs->last_mount, fs->last_mount_size)) {
+                                abort_hibernate(TOI_FAILED_IO, "Failed to "
+                                                "write uuid.");
+                                return -EIO;
+                        }
+                }
+                free_fs_info(fs);
+        }
+        return 0;
+}
+
+static int fs_info_load_and_check_one(void)
+{
+        char uuid[16], *last_mount;
+        int result = 0, ln;
+        dev_t dev_t;
+        struct block_device *dev;
+        struct fs_info *fs_info, seek;
+
+        if (toiActiveAllocator->rw_header_chunk(READ, NULL, uuid, 16)) {
+                abort_hibernate(TOI_FAILED_IO, "Failed to read uuid.");
+                return -EIO;
+        }
+
+        read_if_version(3, dev_t, "uuid dev_t field", return -EIO);
+
+        if (toiActiveAllocator->rw_header_chunk(READ, NULL, (char *) &ln,
+                                sizeof(int))) {
+                abort_hibernate(TOI_FAILED_IO,
+                                "Failed to read last mount size.");
+                return -EIO;
+        }
+
+        last_mount = kzalloc(ln, GFP_KERNEL);
+
+        if (!last_mount)
+                return -ENOMEM;
+
+        if (toiActiveAllocator->rw_header_chunk(READ, NULL, last_mount,        ln)) {
+                abort_hibernate(TOI_FAILED_IO,
+                                "Failed to read last mount timestamp.");
+                result = -EIO;
+                goto out_lmt;
+        }
+
+        strncpy((char *) &seek.uuid, uuid, 16);
+        seek.dev_t = dev_t;
+        seek.last_mount_size = ln;
+        seek.last_mount = last_mount;
+        dev_t = blk_lookup_fs_info(&seek);
+        if (!dev_t)
+                goto out_lmt;
+
+        dev = toi_open_by_devnum(dev_t);
+
+        fs_info = fs_info_from_block_dev(dev);
+        if (fs_info && !IS_ERR(fs_info)) {
+                if (ln != fs_info->last_mount_size) {
+                        printk(KERN_EMERG "Found matching uuid but last mount "
+                                        "time lengths differ?! "
+                                        "(%d vs %d).\n", ln,
+                                        fs_info->last_mount_size);
+                        result = -EINVAL;
+                } else {
+                        char buf[BDEVNAME_SIZE];
+                        result = !!memcmp(fs_info->last_mount, last_mount, ln);
+                        if (result)
+                                printk(KERN_EMERG "Last mount time for %s has "
+                                        "changed!\n", bdevname(dev, buf));
+                }
+        }
+        toi_close_bdev(dev);
+        free_fs_info(fs_info);
+out_lmt:
+        kfree(last_mount);
+        return result;
+}
+
+static int fs_info_load_and_check(void)
+{
+        int to_do, result = 0;
+
+        if (toiActiveAllocator->rw_header_chunk(READ, NULL, (char *) &to_do,
+                                sizeof(int))) {
+                abort_hibernate(TOI_FAILED_IO, "Failed to read num fs_info "
+                                "to load.");
+                return -EIO;
+        }
+
+        while(to_do--)
+                result |= fs_info_load_and_check_one();
+
+        return result;
+}
+
+/**
+ * write_image_header - write the image header after write the image proper
+ *
+ * Returns: Int
+ *        Zero on success, error value otherwise.
+ **/
+int write_image_header(void)
+{
+        int ret;
+        int total = pagedir1.size + pagedir2.size+2;
+        char *header_buffer = NULL;
+
+        /* Now prepare to write the header */
+        ret = toiActiveAllocator->write_header_init();
+        if (ret) {
+                abort_hibernate(TOI_FAILED_MODULE_INIT,
+                                "Active allocator's write_header_init"
+                                " function failed.");
+                goto write_image_header_abort;
+        }
+
+        /* Get a buffer */
+        header_buffer = (char *) toi_get_zeroed_page(24, TOI_ATOMIC_GFP);
+        if (!header_buffer) {
+                abort_hibernate(TOI_OUT_OF_MEMORY,
+                        "Out of memory when trying to get page for header!");
+                goto write_image_header_abort;
+        }
+
+        /* Write hibernate header */
+        if (fill_toi_header((struct toi_header *) header_buffer)) {
+                abort_hibernate(TOI_OUT_OF_MEMORY,
+                        "Failure to fill header information!");
+                goto write_image_header_abort;
+        }
+
+        if (toiActiveAllocator->rw_header_chunk(WRITE, NULL,
+                        header_buffer, sizeof(struct toi_header))) {
+                abort_hibernate(TOI_OUT_OF_MEMORY,
+                        "Failure to write header info.");
+                goto write_image_header_abort;
+        }
+
+        if (toiActiveAllocator->rw_header_chunk(WRITE, NULL,
+                        (char *) &toi_max_workers, sizeof(toi_max_workers))) {
+                abort_hibernate(TOI_OUT_OF_MEMORY,
+                        "Failure to number of workers to use.");
+                goto write_image_header_abort;
+        }
+
+        /* Write filesystem info */
+        if (fs_info_save())
+                goto write_image_header_abort;
+
+        /* Write module configurations */
+        ret = write_module_configs();
+        if (ret) {
+                abort_hibernate(TOI_FAILED_IO,
+                                "Failed to write module configs.");
+                goto write_image_header_abort;
+        }
+
+        if (memory_bm_write(pageset1_map,
+                                toiActiveAllocator->rw_header_chunk)) {
+                abort_hibernate(TOI_FAILED_IO,
+                                "Failed to write bitmaps.");
+                goto write_image_header_abort;
+        }
+
+        /* Flush data and let allocator cleanup */
+        if (toiActiveAllocator->write_header_cleanup()) {
+                abort_hibernate(TOI_FAILED_IO,
+                                "Failed to cleanup writing header.");
+                goto write_image_header_abort_no_cleanup;
+        }
+
+        if (test_result_state(TOI_ABORTED))
+                goto write_image_header_abort_no_cleanup;
+
+        toi_update_status(total, total, NULL);
+
+out:
+        if (header_buffer)
+                toi_free_page(24, (unsigned long) header_buffer);
+        return ret;
+
+write_image_header_abort:
+        toiActiveAllocator->write_header_cleanup();
+write_image_header_abort_no_cleanup:
+        ret = -1;
+        goto out;
+}
+
+/**
+ * sanity_check - check the header
+ * @sh:        the header which was saved at hibernate time.
+ *
+ * Perform a few checks, seeking to ensure that the kernel being
+ * booted matches the one hibernated. They need to match so we can
+ * be _sure_ things will work. It is not absolutely impossible for
+ * resuming from a different kernel to work, just not assured.
+ **/
+static char *sanity_check(struct toi_header *sh)
+{
+        char *reason = check_image_kernel((struct swsusp_info *) sh);
+
+        if (reason)
+                return reason;
+
+        if (!test_action_state(TOI_IGNORE_ROOTFS)) {
+                const struct super_block *sb;
+                list_for_each_entry(sb, &super_blocks, s_list) {
+                        if ((!(sb->s_flags & MS_RDONLY)) &&
+                            (sb->s_type->fs_flags & FS_REQUIRES_DEV))
+                                return "Device backed fs has been mounted "
+                                        "rw prior to resume or initrd/ramfs "
+                                        "is mounted rw.";
+                }
+        }
+
+        return NULL;
+}
+
+static DECLARE_WAIT_QUEUE_HEAD(freeze_wait);
+
+#define FREEZE_IN_PROGRESS (~0)
+
+static int freeze_result;
+
+static void do_freeze(struct work_struct *dummy)
+{
+        freeze_result = freeze_processes();
+        wake_up(&freeze_wait);
+        trap_non_toi_io = 1;
+}
+
+static DECLARE_WORK(freeze_work, do_freeze);
+
+/**
+ * __read_pageset1 - test for the existence of an image and attempt to load it
+ *
+ * Returns:        Int
+ *        Zero if image found and pageset1 successfully loaded.
+ *        Error if no image found or loaded.
+ **/
+static int __read_pageset1(void)
+{
+        int i, result = 0;
+        char *header_buffer = (char *) toi_get_zeroed_page(25, TOI_ATOMIC_GFP),
+             *sanity_error = NULL;
+        struct toi_header *toi_header;
+
+        if (!header_buffer) {
+                printk(KERN_INFO "Unable to allocate a page for reading the "
+                                "signature.\n");
+                return -ENOMEM;
+        }
+
+        /* Check for an image */
+        result = toiActiveAllocator->image_exists(1);
+        if (result == 3) {
+                result = -ENODATA;
+                toi_early_boot_message(1, 0, "The signature from an older "
+                                "version of TuxOnIce has been detected.");
+                goto out_remove_image;
+        }
+
+        if (result != 1) {
+                result = -ENODATA;
+                noresume_reset_modules();
+                printk(KERN_INFO "TuxOnIce: No image found.\n");
+                goto out;
+        }
+
+        /*
+         * Prepare the active allocator for reading the image header. The
+         * activate allocator might read its own configuration.
+         *
+         * NB: This call may never return because there might be a signature
+         * for a different image such that we warn the user and they choose
+         * to reboot. (If the device ids look erroneous (2.4 vs 2.6) or the
+         * location of the image might be unavailable if it was stored on a
+         * network connection).
+         */
+
+        result = toiActiveAllocator->read_header_init();
+        if (result) {
+                printk(KERN_INFO "TuxOnIce: Failed to initialise, reading the "
+                                "image header.\n");
+                goto out_remove_image;
+        }
+
+        /* Check for noresume command line option */
+        if (test_toi_state(TOI_NORESUME_SPECIFIED)) {
+                printk(KERN_INFO "TuxOnIce: Noresume on command line. Removed "
+                                "image.\n");
+                goto out_remove_image;
+        }
+
+        /* Check whether we've resumed before */
+        if (test_toi_state(TOI_RESUMED_BEFORE)) {
+                toi_early_boot_message(1, 0, NULL);
+                if (!(test_toi_state(TOI_CONTINUE_REQ))) {
+                        printk(KERN_INFO "TuxOnIce: Tried to resume before: "
+                                        "Invalidated image.\n");
+                        goto out_remove_image;
+                }
+        }
+
+        clear_toi_state(TOI_CONTINUE_REQ);
+
+        toi_image_header_version = toiActiveAllocator->get_header_version();
+
+        if (unlikely(toi_image_header_version > TOI_HEADER_VERSION)) {
+                toi_early_boot_message(1, 0, image_version_error);
+                if (!(test_toi_state(TOI_CONTINUE_REQ))) {
+                        printk(KERN_INFO "TuxOnIce: Header version too new: "
+                                        "Invalidated image.\n");
+                        goto out_remove_image;
+                }
+        }
+
+        /* Read hibernate header */
+        result = toiActiveAllocator->rw_header_chunk(READ, NULL,
+                        header_buffer, sizeof(struct toi_header));
+        if (result < 0) {
+                printk(KERN_ERR "TuxOnIce: Failed to read the image "
+                                "signature.\n");
+                goto out_remove_image;
+        }
+
+        toi_header = (struct toi_header *) header_buffer;
+
+        /*
+         * NB: This call may also result in a reboot rather than returning.
+         */
+
+        sanity_error = sanity_check(toi_header);
+        if (sanity_error) {
+                toi_early_boot_message(1, TOI_CONTINUE_REQ,
+                                sanity_error);
+                printk(KERN_INFO "TuxOnIce: Sanity check failed.\n");
+                goto out_remove_image;
+        }
+
+        /*
+         * We have an image and it looks like it will load okay.
+         *
+         * Get metadata from header. Don't override commandline parameters.
+         *
+         * We don't need to save the image size limit because it's not used
+         * during resume and will be restored with the image anyway.
+         */
+
+        memcpy((char *) &pagedir1,
+                (char *) &toi_header->pagedir, sizeof(pagedir1));
+        toi_result = toi_header->param0;
+        if (!toi_bkd.toi_debug_state) {
+                toi_bkd.toi_action =
+                        (toi_header->param1 & ~toi_bootflags_mask) |
+                        (toi_bkd.toi_action & toi_bootflags_mask);
+                toi_bkd.toi_debug_state = toi_header->param2;
+                toi_bkd.toi_default_console_level = toi_header->param3;
+        }
+        clear_toi_state(TOI_IGNORE_LOGLEVEL);
+        pagedir2.size = toi_header->pageset_2_size;
+        for (i = 0; i < 4; i++)
+                toi_bkd.toi_io_time[i/2][i%2] =
+                        toi_header->io_time[i/2][i%2];
+
+        set_toi_state(TOI_BOOT_KERNEL);
+        boot_kernel_data_buffer = toi_header->bkd;
+
+        read_if_version(1, toi_max_workers, "TuxOnIce max workers",
+                        goto out_remove_image);
+
+        /* Read filesystem info */
+        if (fs_info_load_and_check()) {
+                printk(KERN_EMERG "TuxOnIce: File system mount time checks "
+                        "failed. Refusing to corrupt your filesystems!\n");
+                goto out_remove_image;
+        }
+
+        /* Read module configurations */
+        result = read_module_configs();
+        if (result) {
+                pagedir1.size = 0;
+                pagedir2.size = 0;
+                printk(KERN_INFO "TuxOnIce: Failed to read TuxOnIce module "
+                                "configurations.\n");
+                clear_action_state(TOI_KEEP_IMAGE);
+                goto out_remove_image;
+        }
+
+        toi_prepare_console();
+
+        set_toi_state(TOI_NOW_RESUMING);
+
+        result = pm_notifier_call_chain(PM_RESTORE_PREPARE);
+        if (result)
+                goto out_notifier_call_chain;;
+
+        if (usermodehelper_disable())
+                goto out_enable_usermodehelper;
+
+        current->flags |= PF_NOFREEZE;
+        freeze_result = FREEZE_IN_PROGRESS;
+
+        schedule_work_on(cpumask_first(cpu_online_mask), &freeze_work);
+
+        toi_cond_pause(1, "About to read original pageset1 locations.");
+
+        /*
+         * See _toi_rw_header_chunk in tuxonice_bio.c:
+         * Initialize pageset1_map by reading the map from the image.
+         */
+        if (memory_bm_read(pageset1_map, toiActiveAllocator->rw_header_chunk))
+                goto out_thaw;
+
+        /*
+         * See toi_rw_cleanup in tuxonice_bio.c:
+         * Clean up after reading the header.
+         */
+        result = toiActiveAllocator->read_header_cleanup();
+        if (result) {
+                printk(KERN_ERR "TuxOnIce: Failed to cleanup after reading the "
+                                "image header.\n");
+                goto out_thaw;
+        }
+
+        toi_cond_pause(1, "About to read pagedir.");
+
+        /*
+         * Get the addresses of pages into which we will load the kernel to
+         * be copied back and check if they conflict with the ones we are using.
+         */
+        if (toi_get_pageset1_load_addresses()) {
+                printk(KERN_INFO "TuxOnIce: Failed to get load addresses for "
+                                "pageset1.\n");
+                goto out_thaw;
+        }
+
+        /* Read the original kernel back */
+        toi_cond_pause(1, "About to read pageset 1.");
+
+        /* Given the pagemap, read back the data from disk */
+        if (read_pageset(&pagedir1, 0)) {
+                toi_prepare_status(DONT_CLEAR_BAR, "Failed to read pageset 1.");
+                result = -EIO;
+                goto out_thaw;
+        }
+
+        toi_cond_pause(1, "About to restore original kernel.");
+        result = 0;
+
+        if (!toi_keeping_image &&
+            toiActiveAllocator->mark_resume_attempted)
+                toiActiveAllocator->mark_resume_attempted(1);
+
+        wait_event(freeze_wait, freeze_result != FREEZE_IN_PROGRESS);
+out:
+        current->flags &= ~PF_NOFREEZE;
+        toi_free_page(25, (unsigned long) header_buffer);
+        return result;
+
+out_thaw:
+        wait_event(freeze_wait, freeze_result != FREEZE_IN_PROGRESS);
+        trap_non_toi_io = 0;
+        thaw_processes();
+out_enable_usermodehelper:
+        usermodehelper_enable();
+out_notifier_call_chain:
+        pm_notifier_call_chain(PM_POST_RESTORE);
+        toi_cleanup_console();
+out_remove_image:
+        result = -EINVAL;
+        if (!toi_keeping_image)
+                toiActiveAllocator->remove_image();
+        toiActiveAllocator->read_header_cleanup();
+        noresume_reset_modules();
+        goto out;
+}
+
+/**
+ * read_pageset1 - highlevel function to read the saved pages
+ *
+ * Attempt to read the header and pageset1 of a hibernate image.
+ * Handle the outcome, complaining where appropriate.
+ **/
+int read_pageset1(void)
+{
+        int error;
+
+        error = __read_pageset1();
+
+        if (error && error != -ENODATA && error != -EINVAL &&
+                                        !test_result_state(TOI_ABORTED))
+                abort_hibernate(TOI_IMAGE_ERROR,
+                        "TuxOnIce: Error %d resuming\n", error);
+
+        return error;
+}
+
+/**
+ * get_have_image_data - check the image header
+ **/
+static char *get_have_image_data(void)
+{
+        char *output_buffer = (char *) toi_get_zeroed_page(26, TOI_ATOMIC_GFP);
+        struct toi_header *toi_header;
+
+        if (!output_buffer) {
+                printk(KERN_INFO "Output buffer null.\n");
+                return NULL;
+        }
+
+        /* Check for an image */
+        if (!toiActiveAllocator->image_exists(1) ||
+            toiActiveAllocator->read_header_init() ||
+            toiActiveAllocator->rw_header_chunk(READ, NULL,
+                        output_buffer, sizeof(struct toi_header))) {
+                sprintf(output_buffer, "0\n");
+                /*
+                 * From an initrd/ramfs, catting have_image and
+                 * getting a result of 0 is sufficient.
+                 */
+                clear_toi_state(TOI_BOOT_TIME);
+                goto out;
+        }
+
+        toi_header = (struct toi_header *) output_buffer;
+
+        sprintf(output_buffer, "1\n%s\n%s\n",
+                        toi_header->uts.machine,
+                        toi_header->uts.version);
+
+        /* Check whether we've resumed before */
+        if (test_toi_state(TOI_RESUMED_BEFORE))
+                strcat(output_buffer, "Resumed before.\n");
+
+out:
+        noresume_reset_modules();
+        return output_buffer;
+}
+
+/**
+ * read_pageset2 - read second part of the image
+ * @overwrittenpagesonly:        Read only pages which would have been
+ *                                verwritten by pageset1?
+ *
+ * Read in part or all of pageset2 of an image, depending upon
+ * whether we are hibernating and have only overwritten a portion
+ * with pageset1 pages, or are resuming and need to read them
+ * all.
+ *
+ * Returns: Int
+ *        Zero if no error, otherwise the error value.
+ **/
+int read_pageset2(int overwrittenpagesonly)
+{
+        int result = 0;
+
+        if (!pagedir2.size)
+                return 0;
+
+        result = read_pageset(&pagedir2, overwrittenpagesonly);
+
+        toi_cond_pause(1, "Pagedir 2 read.");
+
+        return result;
+}
+
+/**
+ * image_exists_read - has an image been found?
+ * @page:        Output buffer
+ *
+ * Store 0 or 1 in page, depending on whether an image is found.
+ * Incoming buffer is PAGE_SIZE and result is guaranteed
+ * to be far less than that, so we don't worry about
+ * overflow.
+ **/
+int image_exists_read(const char *page, int count)
+{
+        int len = 0;
+        char *result;
+
+        if (toi_activate_storage(0))
+                return count;
+
+        if (!test_toi_state(TOI_RESUME_DEVICE_OK))
+                toi_attempt_to_parse_resume_device(0);
+
+        if (!toiActiveAllocator) {
+                len = sprintf((char *) page, "-1\n");
+        } else {
+                result = get_have_image_data();
+                if (result) {
+                        len = sprintf((char *) page, "%s",  result);
+                        toi_free_page(26, (unsigned long) result);
+                }
+        }
+
+        toi_deactivate_storage(0);
+
+        return len;
+}
+
+/**
+ * image_exists_write - invalidate an image if one exists
+ **/
+int image_exists_write(const char *buffer, int count)
+{
+        if (toi_activate_storage(0))
+                return count;
+
+        if (toiActiveAllocator && toiActiveAllocator->image_exists(1))
+                toiActiveAllocator->remove_image();
+
+        toi_deactivate_storage(0);
+
+        clear_result_state(TOI_KEPT_IMAGE);
+
+        return count;
+}
diff --git a/kernel/power/tuxonice_io.h b/kernel/power/tuxonice_io.h
new file mode 100644
index 000000000..683eab7a0
--- /dev/null
+++ b/kernel/power/tuxonice_io.h
@@ -0,0 +1,72 @@
+/*
+ * kernel/power/tuxonice_io.h
+ *
+ * Copyright (C) 2005-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * It contains high level IO routines for hibernating.
+ *
+ */
+
+#include <linux/utsname.h>
+#include "tuxonice_pagedir.h"
+
+/* Non-module data saved in our image header */
+struct toi_header {
+        /*
+         * Mirror struct swsusp_info, but without
+         * the page aligned attribute
+         */
+        struct new_utsname uts;
+        u32 version_code;
+        unsigned long num_physpages;
+        int cpus;
+        unsigned long image_pages;
+        unsigned long pages;
+        unsigned long size;
+
+        /* Our own data */
+        unsigned long orig_mem_free;
+        int page_size;
+        int pageset_2_size;
+        int param0;
+        int param1;
+        int param2;
+        int param3;
+        int progress0;
+        int progress1;
+        int progress2;
+        int progress3;
+        int io_time[2][2];
+        struct pagedir pagedir;
+        dev_t root_fs;
+        unsigned long bkd; /* Boot kernel data locn */
+};
+
+extern int write_pageset(struct pagedir *pagedir);
+extern int write_image_header(void);
+extern int read_pageset1(void);
+extern int read_pageset2(int overwrittenpagesonly);
+
+extern int toi_attempt_to_parse_resume_device(int quiet);
+extern void attempt_to_parse_resume_device2(void);
+extern void attempt_to_parse_alt_resume_param(void);
+int image_exists_read(const char *page, int count);
+int image_exists_write(const char *buffer, int count);
+extern void save_restore_alt_param(int replace, int quiet);
+extern atomic_t toi_io_workers;
+
+/* Args to save_restore_alt_param */
+#define RESTORE 0
+#define SAVE 1
+
+#define NOQUIET 0
+#define QUIET 1
+
+extern wait_queue_head_t toi_io_queue_flusher;
+extern int toi_bio_queue_flusher_should_finish;
+
+int fs_info_space_needed(void);
+
+extern int toi_max_workers;
diff --git a/kernel/power/tuxonice_modules.c b/kernel/power/tuxonice_modules.c
new file mode 100644
index 000000000..a203c8fb9
--- /dev/null
+++ b/kernel/power/tuxonice_modules.c
@@ -0,0 +1,520 @@
+/*
+ * kernel/power/tuxonice_modules.c
+ *
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ */
+
+#include <linux/suspend.h>
+#include <linux/module.h>
+#include "tuxonice.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice_ui.h"
+
+LIST_HEAD(toi_filters);
+LIST_HEAD(toiAllocators);
+
+LIST_HEAD(toi_modules);
+
+struct toi_module_ops *toiActiveAllocator;
+
+static int toi_num_filters;
+int toiNumAllocators, toi_num_modules;
+
+/*
+ * toi_header_storage_for_modules
+ *
+ * Returns the amount of space needed to store configuration
+ * data needed by the modules prior to copying back the original
+ * kernel. We can exclude data for pageset2 because it will be
+ * available anyway once the kernel is copied back.
+ */
+long toi_header_storage_for_modules(void)
+{
+        struct toi_module_ops *this_module;
+        int bytes = 0;
+
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                if (!this_module->enabled ||
+                    (this_module->type == WRITER_MODULE &&
+                     toiActiveAllocator != this_module))
+                        continue;
+                if (this_module->storage_needed) {
+                        int this = this_module->storage_needed() +
+                                sizeof(struct toi_module_header) +
+                                sizeof(int);
+                        this_module->header_requested = this;
+                        bytes += this;
+                }
+        }
+
+        /* One more for the empty terminator */
+        return bytes + sizeof(struct toi_module_header);
+}
+
+void print_toi_header_storage_for_modules(void)
+{
+        struct toi_module_ops *this_module;
+        int bytes = 0;
+
+        printk(KERN_DEBUG "Header storage:\n");
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                if (!this_module->enabled ||
+                    (this_module->type == WRITER_MODULE &&
+                     toiActiveAllocator != this_module))
+                        continue;
+                if (this_module->storage_needed) {
+                        int this = this_module->storage_needed() +
+                                sizeof(struct toi_module_header) +
+                                sizeof(int);
+                        this_module->header_requested = this;
+                        bytes += this;
+                        printk(KERN_DEBUG "+ %16s : %-4d/%d.\n",
+                                        this_module->name,
+                                        this_module->header_used, this);
+                }
+        }
+
+        printk(KERN_DEBUG "+ empty terminator : %zu.\n",
+                        sizeof(struct toi_module_header));
+        printk(KERN_DEBUG "                     ====\n");
+        printk(KERN_DEBUG "                     %zu\n",
+                        bytes + sizeof(struct toi_module_header));
+}
+
+/*
+ * toi_memory_for_modules
+ *
+ * Returns the amount of memory requested by modules for
+ * doing their work during the cycle.
+ */
+
+long toi_memory_for_modules(int print_parts)
+{
+        long bytes = 0, result;
+        struct toi_module_ops *this_module;
+
+        if (print_parts)
+                printk(KERN_INFO "Memory for modules:\n===================\n");
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                int this;
+                if (!this_module->enabled)
+                        continue;
+                if (this_module->memory_needed) {
+                        this = this_module->memory_needed();
+                        if (print_parts)
+                                printk(KERN_INFO "%10d bytes (%5ld pages) for "
+                                                "module '%s'.\n", this,
+                                                DIV_ROUND_UP(this, PAGE_SIZE),
+                                                this_module->name);
+                        bytes += this;
+                }
+        }
+
+        result = DIV_ROUND_UP(bytes, PAGE_SIZE);
+        if (print_parts)
+                printk(KERN_INFO " => %ld bytes, %ld pages.\n", bytes, result);
+
+        return result;
+}
+
+/*
+ * toi_expected_compression_ratio
+ *
+ * Returns the compression ratio expected when saving the image.
+ */
+
+int toi_expected_compression_ratio(void)
+{
+        int ratio = 100;
+        struct toi_module_ops *this_module;
+
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                if (!this_module->enabled)
+                        continue;
+                if (this_module->expected_compression)
+                        ratio = ratio * this_module->expected_compression()
+                                / 100;
+        }
+
+        return ratio;
+}
+
+/* toi_find_module_given_dir
+ * Functionality :        Return a module (if found), given a pointer
+ *                         to its directory name
+ */
+
+static struct toi_module_ops *toi_find_module_given_dir(char *name)
+{
+        struct toi_module_ops *this_module, *found_module = NULL;
+
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                if (!strcmp(name, this_module->directory)) {
+                        found_module = this_module;
+                        break;
+                }
+        }
+
+        return found_module;
+}
+
+/* toi_find_module_given_name
+ * Functionality :        Return a module (if found), given a pointer
+ *                         to its name
+ */
+
+struct toi_module_ops *toi_find_module_given_name(char *name)
+{
+        struct toi_module_ops *this_module, *found_module = NULL;
+
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                if (!strcmp(name, this_module->name)) {
+                        found_module = this_module;
+                        break;
+                }
+        }
+
+        return found_module;
+}
+
+/*
+ * toi_print_module_debug_info
+ * Functionality   : Get debugging info from modules into a buffer.
+ */
+int toi_print_module_debug_info(char *buffer, int buffer_size)
+{
+        struct toi_module_ops *this_module;
+        int len = 0;
+
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                if (!this_module->enabled)
+                        continue;
+                if (this_module->print_debug_info) {
+                        int result;
+                        result = this_module->print_debug_info(buffer + len,
+                                        buffer_size - len);
+                        len += result;
+                }
+        }
+
+        /* Ensure null terminated */
+        buffer[buffer_size] = 0;
+
+        return len;
+}
+
+/*
+ * toi_register_module
+ *
+ * Register a module.
+ */
+int toi_register_module(struct toi_module_ops *module)
+{
+        int i;
+        struct kobject *kobj;
+
+        if (!hibernation_available())
+          return -ENODEV;
+
+        module->enabled = 1;
+
+        if (toi_find_module_given_name(module->name)) {
+                printk(KERN_INFO "TuxOnIce: Trying to load module %s,"
+                                " which is already registered.\n",
+                                module->name);
+                return -EBUSY;
+        }
+
+        switch (module->type) {
+        case FILTER_MODULE:
+                list_add_tail(&module->type_list, &toi_filters);
+                toi_num_filters++;
+                break;
+        case WRITER_MODULE:
+                list_add_tail(&module->type_list, &toiAllocators);
+                toiNumAllocators++;
+                break;
+        case MISC_MODULE:
+        case MISC_HIDDEN_MODULE:
+        case BIO_ALLOCATOR_MODULE:
+                break;
+        default:
+                printk(KERN_ERR "Hmmm. Module '%s' has an invalid type."
+                        " It has been ignored.\n", module->name);
+                return -EINVAL;
+        }
+        list_add_tail(&module->module_list, &toi_modules);
+        toi_num_modules++;
+
+        if ((!module->directory && !module->shared_directory) ||
+                        !module->sysfs_data || !module->num_sysfs_entries)
+                return 0;
+
+        /*
+         * Modules may share a directory, but those with shared_dir
+         * set must be loaded (via symbol dependencies) after parents
+         * and unloaded beforehand.
+         */
+        if (module->shared_directory) {
+                struct toi_module_ops *shared =
+                        toi_find_module_given_dir(module->shared_directory);
+                if (!shared) {
+                        printk(KERN_ERR "TuxOnIce: Module %s wants to share "
+                                        "%s's directory but %s isn't loaded.\n",
+                                        module->name, module->shared_directory,
+                                        module->shared_directory);
+                        toi_unregister_module(module);
+                        return -ENODEV;
+                }
+                kobj = shared->dir_kobj;
+        } else {
+                if (!strncmp(module->directory, "[ROOT]", 6))
+                        kobj = tuxonice_kobj;
+                else
+                        kobj = make_toi_sysdir(module->directory);
+        }
+        module->dir_kobj = kobj;
+        for (i = 0; i < module->num_sysfs_entries; i++) {
+                int result = toi_register_sysfs_file(kobj,
+                                &module->sysfs_data[i]);
+                if (result)
+                        return result;
+        }
+        return 0;
+}
+
+/*
+ * toi_unregister_module
+ *
+ * Remove a module.
+ */
+void toi_unregister_module(struct toi_module_ops *module)
+{
+        int i;
+
+        if (module->dir_kobj)
+                for (i = 0; i < module->num_sysfs_entries; i++)
+                        toi_unregister_sysfs_file(module->dir_kobj,
+                                        &module->sysfs_data[i]);
+
+        if (!module->shared_directory && module->directory &&
+                        strncmp(module->directory, "[ROOT]", 6))
+                remove_toi_sysdir(module->dir_kobj);
+
+        switch (module->type) {
+        case FILTER_MODULE:
+                list_del(&module->type_list);
+                toi_num_filters--;
+                break;
+        case WRITER_MODULE:
+                list_del(&module->type_list);
+                toiNumAllocators--;
+                if (toiActiveAllocator == module) {
+                        toiActiveAllocator = NULL;
+                        clear_toi_state(TOI_CAN_RESUME);
+                        clear_toi_state(TOI_CAN_HIBERNATE);
+                }
+                break;
+        case MISC_MODULE:
+        case MISC_HIDDEN_MODULE:
+        case BIO_ALLOCATOR_MODULE:
+                break;
+        default:
+                printk(KERN_ERR "Module '%s' has an invalid type."
+                        " It has been ignored.\n", module->name);
+                return;
+        }
+        list_del(&module->module_list);
+        toi_num_modules--;
+}
+
+/*
+ * toi_move_module_tail
+ *
+ * Rearrange modules when reloading the config.
+ */
+void toi_move_module_tail(struct toi_module_ops *module)
+{
+        switch (module->type) {
+        case FILTER_MODULE:
+                if (toi_num_filters > 1)
+                        list_move_tail(&module->type_list, &toi_filters);
+                break;
+        case WRITER_MODULE:
+                if (toiNumAllocators > 1)
+                        list_move_tail(&module->type_list, &toiAllocators);
+                break;
+        case MISC_MODULE:
+        case MISC_HIDDEN_MODULE:
+        case BIO_ALLOCATOR_MODULE:
+                break;
+        default:
+                printk(KERN_ERR "Module '%s' has an invalid type."
+                        " It has been ignored.\n", module->name);
+                return;
+        }
+        if ((toi_num_filters + toiNumAllocators) > 1)
+                list_move_tail(&module->module_list, &toi_modules);
+}
+
+/*
+ * toi_initialise_modules
+ *
+ * Get ready to do some work!
+ */
+int toi_initialise_modules(int starting_cycle, int early)
+{
+        struct toi_module_ops *this_module;
+        int result;
+
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                this_module->header_requested = 0;
+                this_module->header_used = 0;
+                if (!this_module->enabled)
+                        continue;
+                if (this_module->early != early)
+                        continue;
+                if (this_module->initialise) {
+                        result = this_module->initialise(starting_cycle);
+                        if (result) {
+                                toi_cleanup_modules(starting_cycle);
+                                return result;
+                        }
+                        this_module->initialised = 1;
+                }
+        }
+
+        return 0;
+}
+
+/*
+ * toi_cleanup_modules
+ *
+ * Tell modules the work is done.
+ */
+void toi_cleanup_modules(int finishing_cycle)
+{
+        struct toi_module_ops *this_module;
+
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                if (!this_module->enabled || !this_module->initialised)
+                        continue;
+                if (this_module->cleanup)
+                        this_module->cleanup(finishing_cycle);
+                this_module->initialised = 0;
+        }
+}
+
+/*
+ * toi_pre_atomic_restore_modules
+ *
+ * Get ready to do some work!
+ */
+void toi_pre_atomic_restore_modules(struct toi_boot_kernel_data *bkd)
+{
+        struct toi_module_ops *this_module;
+
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                if (this_module->enabled && this_module->pre_atomic_restore)
+                        this_module->pre_atomic_restore(bkd);
+        }
+}
+
+/*
+ * toi_post_atomic_restore_modules
+ *
+ * Get ready to do some work!
+ */
+void toi_post_atomic_restore_modules(struct toi_boot_kernel_data *bkd)
+{
+        struct toi_module_ops *this_module;
+
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                if (this_module->enabled && this_module->post_atomic_restore)
+                        this_module->post_atomic_restore(bkd);
+        }
+}
+
+/*
+ * toi_get_next_filter
+ *
+ * Get the next filter in the pipeline.
+ */
+struct toi_module_ops *toi_get_next_filter(struct toi_module_ops *filter_sought)
+{
+        struct toi_module_ops *last_filter = NULL, *this_filter = NULL;
+
+        list_for_each_entry(this_filter, &toi_filters, type_list) {
+                if (!this_filter->enabled)
+                        continue;
+                if ((last_filter == filter_sought) || (!filter_sought))
+                        return this_filter;
+                last_filter = this_filter;
+        }
+
+        return toiActiveAllocator;
+}
+
+/**
+ * toi_show_modules: Printk what support is loaded.
+ */
+void toi_print_modules(void)
+{
+        struct toi_module_ops *this_module;
+        int prev = 0;
+
+        printk(KERN_INFO "TuxOnIce " TOI_CORE_VERSION ", with support for");
+
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                if (this_module->type == MISC_HIDDEN_MODULE)
+                        continue;
+                printk("%s %s%s%s", prev ? "," : "",
+                                this_module->enabled ? "" : "[",
+                                this_module->name,
+                                this_module->enabled ? "" : "]");
+                prev = 1;
+        }
+
+        printk(".\n");
+}
+
+/* toi_get_modules
+ *
+ * Take a reference to modules so they can't go away under us.
+ */
+
+int toi_get_modules(void)
+{
+        struct toi_module_ops *this_module;
+
+        list_for_each_entry(this_module, &toi_modules, module_list) {
+                struct toi_module_ops *this_module2;
+
+                if (try_module_get(this_module->module))
+                        continue;
+
+                /* Failed! Reverse gets and return error */
+                list_for_each_entry(this_module2, &toi_modules,
+                                module_list) {
+                        if (this_module == this_module2)
+                                return -EINVAL;
+                        module_put(this_module2->module);
+                }
+        }
+        return 0;
+}
+
+/* toi_put_modules
+ *
+ * Release our references to modules we used.
+ */
+
+void toi_put_modules(void)
+{
+        struct toi_module_ops *this_module;
+
+        list_for_each_entry(this_module, &toi_modules, module_list)
+                module_put(this_module->module);
+}
diff --git a/kernel/power/tuxonice_modules.h b/kernel/power/tuxonice_modules.h
new file mode 100644
index 000000000..44f10abb9
--- /dev/null
+++ b/kernel/power/tuxonice_modules.h
@@ -0,0 +1,212 @@
+/*
+ * kernel/power/tuxonice_modules.h
+ *
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * It contains declarations for modules. Modules are additions to
+ * TuxOnIce that provide facilities such as image compression or
+ * encryption, backends for storage of the image and user interfaces.
+ *
+ */
+
+#ifndef TOI_MODULES_H
+#define TOI_MODULES_H
+
+/* This is the maximum size we store in the image header for a module name */
+#define TOI_MAX_MODULE_NAME_LENGTH 30
+
+struct toi_boot_kernel_data;
+
+/* Per-module metadata */
+struct toi_module_header {
+        char name[TOI_MAX_MODULE_NAME_LENGTH];
+        int enabled;
+        int type;
+        int index;
+        int data_length;
+        unsigned long signature;
+};
+
+enum {
+        FILTER_MODULE,
+        WRITER_MODULE,
+        BIO_ALLOCATOR_MODULE,
+        MISC_MODULE,
+        MISC_HIDDEN_MODULE,
+};
+
+enum {
+        TOI_ASYNC,
+        TOI_SYNC
+};
+
+enum {
+        TOI_VIRT,
+        TOI_PAGE,
+};
+
+#define TOI_MAP(type, addr) \
+ (type == TOI_PAGE ? kmap(addr) : addr)
+
+#define TOI_UNMAP(type, addr) \
+ do { \
+   if (type == TOI_PAGE) \
+     kunmap(addr); \
+ } while(0)
+
+struct toi_module_ops {
+        /* Functions common to all modules */
+        int type;
+        char *name;
+        char *directory;
+        char *shared_directory;
+        struct kobject *dir_kobj;
+        struct module *module;
+        int enabled, early, initialised;
+        struct list_head module_list;
+
+        /* List of filters or allocators */
+        struct list_head list, type_list;
+
+        /*
+         * Requirements for memory and storage in
+         * the image header..
+         */
+        int (*memory_needed) (void);
+        int (*storage_needed) (void);
+
+        int header_requested, header_used;
+
+        int (*expected_compression) (void);
+
+        /*
+         * Debug info
+         */
+        int (*print_debug_info) (char *buffer, int size);
+        int (*save_config_info) (char *buffer);
+        void (*load_config_info) (char *buffer, int len);
+
+        /*
+         * Initialise & cleanup - general routines called
+         * at the start and end of a cycle.
+         */
+        int (*initialise) (int starting_cycle);
+        void (*cleanup) (int finishing_cycle);
+
+        void (*pre_atomic_restore) (struct toi_boot_kernel_data *bkd);
+        void (*post_atomic_restore) (struct toi_boot_kernel_data *bkd);
+
+        /*
+         * Calls for allocating storage (allocators only).
+         *
+         * Header space is requested separately and cannot fail, but the
+         * reservation is only applied when main storage is allocated.
+         * The header space reservation is thus always set prior to
+         * requesting the allocation of storage - and prior to querying
+         * how much storage is available.
+         */
+
+        unsigned long (*storage_available) (void);
+        void (*reserve_header_space) (unsigned long space_requested);
+        int (*register_storage) (void);
+        int (*allocate_storage) (unsigned long space_requested);
+        unsigned long (*storage_allocated) (void);
+        void (*free_unused_storage) (void);
+
+        /*
+         * Routines used in image I/O.
+         */
+        int (*rw_init) (int rw, int stream_number);
+        int (*rw_cleanup) (int rw);
+        int (*write_page) (unsigned long index, int buf_type, void *buf,
+                        unsigned int buf_size);
+        int (*read_page) (unsigned long *index, int buf_type, void *buf,
+                        unsigned int *buf_size);
+        int (*io_flusher) (int rw);
+
+        /* Reset module if image exists but reading aborted */
+        void (*noresume_reset) (void);
+
+        /* Read and write the metadata */
+        int (*write_header_init) (void);
+        int (*write_header_cleanup) (void);
+
+        int (*read_header_init) (void);
+        int (*read_header_cleanup) (void);
+
+        /* To be called after read_header_init */
+        int (*get_header_version) (void);
+
+        int (*rw_header_chunk) (int rw, struct toi_module_ops *owner,
+                        char *buffer_start, int buffer_size);
+
+        int (*rw_header_chunk_noreadahead) (int rw,
+                        struct toi_module_ops *owner, char *buffer_start,
+                        int buffer_size);
+
+        /* Attempt to parse an image location */
+        int (*parse_sig_location) (char *buffer, int only_writer, int quiet);
+
+        /* Throttle I/O according to throughput */
+        void (*update_throughput_throttle) (int jif_index);
+
+        /* Flush outstanding I/O */
+        int (*finish_all_io) (void);
+
+        /* Determine whether image exists that we can restore */
+        int (*image_exists) (int quiet);
+
+        /* Mark the image as having tried to resume */
+        int (*mark_resume_attempted) (int);
+
+        /* Destroy image if one exists */
+        int (*remove_image) (void);
+
+        /* Sysfs Data */
+        struct toi_sysfs_data *sysfs_data;
+        int num_sysfs_entries;
+
+        /* Block I/O allocator */
+        struct toi_bio_allocator_ops *bio_allocator_ops;
+};
+
+extern int toi_num_modules, toiNumAllocators;
+
+extern struct toi_module_ops *toiActiveAllocator;
+extern struct list_head toi_filters, toiAllocators, toi_modules;
+
+extern void toi_prepare_console_modules(void);
+extern void toi_cleanup_console_modules(void);
+
+extern struct toi_module_ops *toi_find_module_given_name(char *name);
+extern struct toi_module_ops *toi_get_next_filter(struct toi_module_ops *);
+
+extern int toi_register_module(struct toi_module_ops *module);
+extern void toi_move_module_tail(struct toi_module_ops *module);
+
+extern long toi_header_storage_for_modules(void);
+extern long toi_memory_for_modules(int print_parts);
+extern void print_toi_header_storage_for_modules(void);
+extern int toi_expected_compression_ratio(void);
+
+extern int toi_print_module_debug_info(char *buffer, int buffer_size);
+extern int toi_register_module(struct toi_module_ops *module);
+extern void toi_unregister_module(struct toi_module_ops *module);
+
+extern int toi_initialise_modules(int starting_cycle, int early);
+#define toi_initialise_modules_early(starting) \
+        toi_initialise_modules(starting, 1)
+#define toi_initialise_modules_late(starting) \
+        toi_initialise_modules(starting, 0)
+extern void toi_cleanup_modules(int finishing_cycle);
+
+extern void toi_post_atomic_restore_modules(struct toi_boot_kernel_data *bkd);
+extern void toi_pre_atomic_restore_modules(struct toi_boot_kernel_data *bkd);
+
+extern void toi_print_modules(void);
+
+int toi_get_modules(void);
+void toi_put_modules(void);
+#endif
diff --git a/kernel/power/tuxonice_netlink.c b/kernel/power/tuxonice_netlink.c
new file mode 100644
index 000000000..78bd31b05
--- /dev/null
+++ b/kernel/power/tuxonice_netlink.c
@@ -0,0 +1,324 @@
+/*
+ * kernel/power/tuxonice_netlink.c
+ *
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * Functions for communicating with a userspace helper via netlink.
+ */
+
+#include <linux/suspend.h>
+#include <linux/sched.h>
+#include <linux/kmod.h>
+#include "tuxonice_netlink.h"
+#include "tuxonice.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_alloc.h"
+#include "tuxonice_builtin.h"
+
+static struct user_helper_data *uhd_list;
+
+/*
+ * Refill our pool of SKBs for use in emergencies (eg, when eating memory and
+ * none can be allocated).
+ */
+static void toi_fill_skb_pool(struct user_helper_data *uhd)
+{
+        while (uhd->pool_level < uhd->pool_limit) {
+                struct sk_buff *new_skb =
+                        alloc_skb(NLMSG_SPACE(uhd->skb_size), TOI_ATOMIC_GFP);
+
+                if (!new_skb)
+                        break;
+
+                new_skb->next = uhd->emerg_skbs;
+                uhd->emerg_skbs = new_skb;
+                uhd->pool_level++;
+        }
+}
+
+/*
+ * Try to allocate a single skb. If we can't get one, try to use one from
+ * our pool.
+ */
+static struct sk_buff *toi_get_skb(struct user_helper_data *uhd)
+{
+        struct sk_buff *skb =
+                alloc_skb(NLMSG_SPACE(uhd->skb_size), TOI_ATOMIC_GFP);
+
+        if (skb)
+                return skb;
+
+        skb = uhd->emerg_skbs;
+        if (skb) {
+                uhd->pool_level--;
+                uhd->emerg_skbs = skb->next;
+                skb->next = NULL;
+        }
+
+        return skb;
+}
+
+void toi_send_netlink_message(struct user_helper_data *uhd,
+                int type, void *params, size_t len)
+{
+        struct sk_buff *skb;
+        struct nlmsghdr *nlh;
+        void *dest;
+        struct task_struct *t;
+
+        if (uhd->pid == -1)
+                return;
+
+        if (uhd->debug)
+                printk(KERN_ERR "toi_send_netlink_message: Send "
+                                "message type %d.\n", type);
+
+        skb = toi_get_skb(uhd);
+        if (!skb) {
+                printk(KERN_INFO "toi_netlink: Can't allocate skb!\n");
+                return;
+        }
+
+        nlh = nlmsg_put(skb, 0, uhd->sock_seq, type, len, 0);
+        uhd->sock_seq++;
+
+        dest = NLMSG_DATA(nlh);
+        if (params && len > 0)
+                memcpy(dest, params, len);
+
+        netlink_unicast(uhd->nl, skb, uhd->pid, 0);
+
+        toi_read_lock_tasklist();
+        t = find_task_by_pid_ns(uhd->pid, &init_pid_ns);
+        if (!t) {
+                toi_read_unlock_tasklist();
+                if (uhd->pid > -1)
+                        printk(KERN_INFO "Hmm. Can't find the userspace task"
+                                " %d.\n", uhd->pid);
+                return;
+        }
+        wake_up_process(t);
+        toi_read_unlock_tasklist();
+
+        yield();
+}
+
+static void send_whether_debugging(struct user_helper_data *uhd)
+{
+        static u8 is_debugging = 1;
+
+        toi_send_netlink_message(uhd, NETLINK_MSG_IS_DEBUGGING,
+                        &is_debugging, sizeof(u8));
+}
+
+/*
+ * Set the PF_NOFREEZE flag on the given process to ensure it can run whilst we
+ * are hibernating.
+ */
+static int nl_set_nofreeze(struct user_helper_data *uhd, __u32 pid)
+{
+        struct task_struct *t;
+
+        if (uhd->debug)
+                printk(KERN_ERR "nl_set_nofreeze for pid %d.\n", pid);
+
+        toi_read_lock_tasklist();
+        t = find_task_by_pid_ns(pid, &init_pid_ns);
+        if (!t) {
+                toi_read_unlock_tasklist();
+                printk(KERN_INFO "Strange. Can't find the userspace task %d.\n",
+                                pid);
+                return -EINVAL;
+        }
+
+        t->flags |= PF_NOFREEZE;
+
+        toi_read_unlock_tasklist();
+        uhd->pid = pid;
+
+        toi_send_netlink_message(uhd, NETLINK_MSG_NOFREEZE_ACK, NULL, 0);
+
+        return 0;
+}
+
+/*
+ * Called when the userspace process has informed us that it's ready to roll.
+ */
+static int nl_ready(struct user_helper_data *uhd, u32 version)
+{
+        if (version != uhd->interface_version) {
+                printk(KERN_INFO "%s userspace process using invalid interface"
+                                " version (%d - kernel wants %d). Trying to "
+                                "continue without it.\n",
+                                uhd->name, version, uhd->interface_version);
+                if (uhd->not_ready)
+                        uhd->not_ready();
+                return -EINVAL;
+        }
+
+        complete(&uhd->wait_for_process);
+
+        return 0;
+}
+
+void toi_netlink_close_complete(struct user_helper_data *uhd)
+{
+        if (uhd->nl) {
+                netlink_kernel_release(uhd->nl);
+                uhd->nl = NULL;
+        }
+
+        while (uhd->emerg_skbs) {
+                struct sk_buff *next = uhd->emerg_skbs->next;
+                kfree_skb(uhd->emerg_skbs);
+                uhd->emerg_skbs = next;
+        }
+
+        uhd->pid = -1;
+}
+
+static int toi_nl_gen_rcv_msg(struct user_helper_data *uhd,
+                struct sk_buff *skb, struct nlmsghdr *nlh)
+{
+        int type = nlh->nlmsg_type;
+        int *data;
+        int err;
+
+        if (uhd->debug)
+                printk(KERN_ERR "toi_user_rcv_skb: Received message %d.\n",
+                                type);
+
+        /* Let the more specific handler go first. It returns
+         * 1 for valid messages that it doesn't know. */
+        err = uhd->rcv_msg(skb, nlh);
+        if (err != 1)
+                return err;
+
+        /* Only allow one task to receive NOFREEZE privileges */
+        if (type == NETLINK_MSG_NOFREEZE_ME && uhd->pid != -1) {
+                printk(KERN_INFO "Received extra nofreeze me requests.\n");
+                return -EBUSY;
+        }
+
+        data = NLMSG_DATA(nlh);
+
+        switch (type) {
+        case NETLINK_MSG_NOFREEZE_ME:
+                return nl_set_nofreeze(uhd, nlh->nlmsg_pid);
+        case NETLINK_MSG_GET_DEBUGGING:
+                send_whether_debugging(uhd);
+                return 0;
+        case NETLINK_MSG_READY:
+                if (nlh->nlmsg_len != NLMSG_LENGTH(sizeof(u32))) {
+                        printk(KERN_INFO "Invalid ready mesage.\n");
+                        if (uhd->not_ready)
+                                uhd->not_ready();
+                        return -EINVAL;
+                }
+                return nl_ready(uhd, (u32) *data);
+        case NETLINK_MSG_CLEANUP:
+                toi_netlink_close_complete(uhd);
+                return 0;
+        }
+
+        return -EINVAL;
+}
+
+static void toi_user_rcv_skb(struct sk_buff *skb)
+{
+        int err;
+        struct nlmsghdr *nlh;
+        struct user_helper_data *uhd = uhd_list;
+
+        while (uhd && uhd->netlink_id != skb->sk->sk_protocol)
+                uhd = uhd->next;
+
+        if (!uhd)
+                return;
+
+        while (skb->len >= NLMSG_SPACE(0)) {
+                u32 rlen;
+
+                nlh = (struct nlmsghdr *) skb->data;
+                if (nlh->nlmsg_len < sizeof(*nlh) || skb->len < nlh->nlmsg_len)
+                        return;
+
+                rlen = NLMSG_ALIGN(nlh->nlmsg_len);
+                if (rlen > skb->len)
+                        rlen = skb->len;
+
+                err = toi_nl_gen_rcv_msg(uhd, skb, nlh);
+                if (err)
+                        netlink_ack(skb, nlh, err);
+                else if (nlh->nlmsg_flags & NLM_F_ACK)
+                        netlink_ack(skb, nlh, 0);
+                skb_pull(skb, rlen);
+        }
+}
+
+static int netlink_prepare(struct user_helper_data *uhd)
+{
+        struct netlink_kernel_cfg cfg = {
+                .groups = 0,
+                .input = toi_user_rcv_skb,
+        };
+
+        uhd->next = uhd_list;
+        uhd_list = uhd;
+
+        uhd->sock_seq = 0x42c0ffee;
+        uhd->nl = netlink_kernel_create(&init_net, uhd->netlink_id, &cfg);
+        if (!uhd->nl) {
+                printk(KERN_INFO "Failed to allocate netlink socket for %s.\n",
+                                uhd->name);
+                return -ENOMEM;
+        }
+
+        toi_fill_skb_pool(uhd);
+
+        return 0;
+}
+
+void toi_netlink_close(struct user_helper_data *uhd)
+{
+        struct task_struct *t;
+
+        toi_read_lock_tasklist();
+        t = find_task_by_pid_ns(uhd->pid, &init_pid_ns);
+        if (t)
+                t->flags &= ~PF_NOFREEZE;
+        toi_read_unlock_tasklist();
+
+        toi_send_netlink_message(uhd, NETLINK_MSG_CLEANUP, NULL, 0);
+}
+int toi_netlink_setup(struct user_helper_data *uhd)
+{
+        /* In case userui didn't cleanup properly on us */
+        toi_netlink_close_complete(uhd);
+
+        if (netlink_prepare(uhd) < 0) {
+                printk(KERN_INFO "Netlink prepare failed.\n");
+                return 1;
+        }
+
+        if (toi_launch_userspace_program(uhd->program, uhd->netlink_id,
+                                UMH_WAIT_EXEC, uhd->debug) < 0) {
+                printk(KERN_INFO "Launch userspace program failed.\n");
+                toi_netlink_close_complete(uhd);
+                return 1;
+        }
+
+        /* Wait 2 seconds for the userspace process to make contact */
+        wait_for_completion_timeout(&uhd->wait_for_process, 2*HZ);
+
+        if (uhd->pid == -1) {
+                printk(KERN_INFO "%s: Failed to contact userspace process.\n",
+                                uhd->name);
+                toi_netlink_close_complete(uhd);
+                return 1;
+        }
+
+        return 0;
+}
diff --git a/kernel/power/tuxonice_netlink.h b/kernel/power/tuxonice_netlink.h
new file mode 100644
index 000000000..6613c8eaa
--- /dev/null
+++ b/kernel/power/tuxonice_netlink.h
@@ -0,0 +1,62 @@
+/*
+ * kernel/power/tuxonice_netlink.h
+ *
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * Declarations for functions for communicating with a userspace helper
+ * via netlink.
+ */
+
+#include <linux/netlink.h>
+#include <net/sock.h>
+
+#define NETLINK_MSG_BASE 0x10
+
+#define NETLINK_MSG_READY 0x10
+#define        NETLINK_MSG_NOFREEZE_ME 0x16
+#define NETLINK_MSG_GET_DEBUGGING 0x19
+#define NETLINK_MSG_CLEANUP 0x24
+#define NETLINK_MSG_NOFREEZE_ACK 0x27
+#define NETLINK_MSG_IS_DEBUGGING 0x28
+
+struct user_helper_data {
+        int (*rcv_msg) (struct sk_buff *skb, struct nlmsghdr *nlh);
+        void (*not_ready) (void);
+        struct sock *nl;
+        u32 sock_seq;
+        pid_t pid;
+        char *comm;
+        char program[256];
+        int pool_level;
+        int pool_limit;
+        struct sk_buff *emerg_skbs;
+        int skb_size;
+        int netlink_id;
+        char *name;
+        struct user_helper_data *next;
+        struct completion wait_for_process;
+        u32 interface_version;
+        int must_init;
+        int debug;
+};
+
+#ifdef CONFIG_NET
+int toi_netlink_setup(struct user_helper_data *uhd);
+void toi_netlink_close(struct user_helper_data *uhd);
+void toi_send_netlink_message(struct user_helper_data *uhd,
+                int type, void *params, size_t len);
+void toi_netlink_close_complete(struct user_helper_data *uhd);
+#else
+static inline int toi_netlink_setup(struct user_helper_data *uhd)
+{
+        return 0;
+}
+
+static inline void toi_netlink_close(struct user_helper_data *uhd) { };
+static inline void toi_send_netlink_message(struct user_helper_data *uhd,
+                int type, void *params, size_t len) { };
+static inline void toi_netlink_close_complete(struct user_helper_data *uhd)
+        { };
+#endif
diff --git a/kernel/power/tuxonice_pagedir.c b/kernel/power/tuxonice_pagedir.c
new file mode 100644
index 000000000..d469f3d2d
--- /dev/null
+++ b/kernel/power/tuxonice_pagedir.c
@@ -0,0 +1,345 @@
+/*
+ * kernel/power/tuxonice_pagedir.c
+ *
+ * Copyright (C) 1998-2001 Gabor Kuti <seasons@fornax.hu>
+ * Copyright (C) 1998,2001,2002 Pavel Machek <pavel@suse.cz>
+ * Copyright (C) 2002-2003 Florent Chabaud <fchabaud@free.fr>
+ * Copyright (C) 2006-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * Routines for handling pagesets.
+ * Note that pbes aren't actually stored as such. They're stored as
+ * bitmaps and extents.
+ */
+
+#include <linux/suspend.h>
+#include <linux/highmem.h>
+#include <linux/bootmem.h>
+#include <linux/hardirq.h>
+#include <linux/sched.h>
+#include <linux/cpu.h>
+#include <asm/tlbflush.h>
+
+#include "tuxonice_pageflags.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_pagedir.h"
+#include "tuxonice_prepare_image.h"
+#include "tuxonice.h"
+#include "tuxonice_builtin.h"
+#include "tuxonice_alloc.h"
+
+static int ptoi_pfn;
+static struct pbe *this_low_pbe;
+static struct pbe **last_low_pbe_ptr;
+
+void toi_reset_alt_image_pageset2_pfn(void)
+{
+  memory_bm_position_reset(pageset2_map);
+}
+
+static struct page *first_conflicting_page;
+
+/*
+ * free_conflicting_pages
+ */
+
+static void free_conflicting_pages(void)
+{
+        while (first_conflicting_page) {
+                struct page *next =
+                        *((struct page **) kmap(first_conflicting_page));
+                kunmap(first_conflicting_page);
+                toi__free_page(29, first_conflicting_page);
+                first_conflicting_page = next;
+        }
+}
+
+/* __toi_get_nonconflicting_page
+ *
+ * Description: Gets order zero pages that won't be overwritten
+ *                while copying the original pages.
+ */
+
+struct page *___toi_get_nonconflicting_page(int can_be_highmem)
+{
+        struct page *page;
+        gfp_t flags = TOI_ATOMIC_GFP;
+        if (can_be_highmem)
+                flags |= __GFP_HIGHMEM;
+
+
+        if (test_toi_state(TOI_LOADING_ALT_IMAGE) &&
+                        pageset2_map && ptoi_pfn) {
+                do {
+                        ptoi_pfn = memory_bm_next_pfn(pageset2_map, 0);
+                        if (ptoi_pfn != BM_END_OF_MAP) {
+                                page = pfn_to_page(ptoi_pfn);
+                                if (!PagePageset1(page) &&
+                                    (can_be_highmem || !PageHighMem(page)))
+                                        return page;
+                        }
+                } while (ptoi_pfn);
+        }
+
+        do {
+                page = toi_alloc_page(29, flags | __GFP_ZERO);
+                if (!page) {
+                        printk(KERN_INFO "Failed to get nonconflicting "
+                                        "page.\n");
+                        return NULL;
+                }
+                if (PagePageset1(page)) {
+                        struct page **next = (struct page **) kmap(page);
+                        *next = first_conflicting_page;
+                        first_conflicting_page = page;
+                        kunmap(page);
+                }
+        } while (PagePageset1(page));
+
+        return page;
+}
+
+unsigned long __toi_get_nonconflicting_page(void)
+{
+        struct page *page = ___toi_get_nonconflicting_page(0);
+        return page ? (unsigned long) page_address(page) : 0;
+}
+
+static struct pbe *get_next_pbe(struct page **page_ptr, struct pbe *this_pbe,
+                int highmem)
+{
+        if (((((unsigned long) this_pbe) & (PAGE_SIZE - 1))
+                     + 2 * sizeof(struct pbe)) > PAGE_SIZE) {
+                struct page *new_page =
+                        ___toi_get_nonconflicting_page(highmem);
+                if (!new_page)
+                        return ERR_PTR(-ENOMEM);
+                this_pbe = (struct pbe *) kmap(new_page);
+                memset(this_pbe, 0, PAGE_SIZE);
+                *page_ptr = new_page;
+        } else
+                this_pbe++;
+
+        return this_pbe;
+}
+
+/**
+ * get_pageset1_load_addresses - generate pbes for conflicting pages
+ *
+ * We check here that pagedir & pages it points to won't collide
+ * with pages where we're going to restore from the loaded pages
+ * later.
+ *
+ * Returns:
+ *        Zero on success, one if couldn't find enough pages (shouldn't
+ *        happen).
+ **/
+int toi_get_pageset1_load_addresses(void)
+{
+        int pfn, highallocd = 0, lowallocd = 0;
+        int low_needed = pagedir1.size - get_highmem_size(pagedir1);
+        int high_needed = get_highmem_size(pagedir1);
+        int low_pages_for_highmem = 0;
+        gfp_t flags = GFP_ATOMIC | __GFP_NOWARN | __GFP_HIGHMEM;
+        struct page *page, *high_pbe_page = NULL, *last_high_pbe_page = NULL,
+                    *low_pbe_page, *last_low_pbe_page = NULL;
+        struct pbe **last_high_pbe_ptr = &restore_highmem_pblist,
+                   *this_high_pbe = NULL;
+        unsigned long orig_low_pfn, orig_high_pfn;
+        int high_pbes_done = 0, low_pbes_done = 0;
+        int low_direct = 0, high_direct = 0, result = 0, i;
+        int high_page = 1, high_offset = 0, low_page = 1, low_offset = 0;
+
+        toi_trace_index++;
+
+        memory_bm_position_reset(pageset1_map);
+        memory_bm_position_reset(pageset1_copy_map);
+
+        last_low_pbe_ptr = &restore_pblist;
+
+        /* First, allocate pages for the start of our pbe lists. */
+        if (high_needed) {
+                high_pbe_page = ___toi_get_nonconflicting_page(1);
+                if (!high_pbe_page) {
+                        result = -ENOMEM;
+                        goto out;
+                }
+                this_high_pbe = (struct pbe *) kmap(high_pbe_page);
+                memset(this_high_pbe, 0, PAGE_SIZE);
+        }
+
+        low_pbe_page = ___toi_get_nonconflicting_page(0);
+        if (!low_pbe_page) {
+                result = -ENOMEM;
+                goto out;
+        }
+        this_low_pbe = (struct pbe *) page_address(low_pbe_page);
+
+        /*
+         * Next, allocate the number of pages we need.
+         */
+
+        i = low_needed + high_needed;
+
+        do {
+                int is_high;
+
+                if (i == low_needed)
+                        flags &= ~__GFP_HIGHMEM;
+
+                page = toi_alloc_page(30, flags);
+                BUG_ON(!page);
+
+                SetPagePageset1Copy(page);
+                is_high = PageHighMem(page);
+
+                if (PagePageset1(page)) {
+                        if (is_high)
+                                high_direct++;
+                        else
+                                low_direct++;
+                } else {
+                        if (is_high)
+                                highallocd++;
+                        else
+                                lowallocd++;
+                }
+        } while (--i);
+
+        high_needed -= high_direct;
+        low_needed -= low_direct;
+
+        /*
+         * Do we need to use some lowmem pages for the copies of highmem
+         * pages?
+         */
+        if (high_needed > highallocd) {
+                low_pages_for_highmem = high_needed - highallocd;
+                high_needed -= low_pages_for_highmem;
+                low_needed += low_pages_for_highmem;
+        }
+
+        /*
+         * Now generate our pbes (which will be used for the atomic restore),
+         * and free unneeded pages.
+         */
+        memory_bm_position_reset(pageset1_copy_map);
+        for (pfn = memory_bm_next_pfn(pageset1_copy_map, 0); pfn != BM_END_OF_MAP;
+                        pfn = memory_bm_next_pfn(pageset1_copy_map, 0)) {
+                int is_high;
+                page = pfn_to_page(pfn);
+                is_high = PageHighMem(page);
+
+                if (PagePageset1(page))
+                        continue;
+
+                /* Nope. We're going to use this page. Add a pbe. */
+                if (is_high || low_pages_for_highmem) {
+                        struct page *orig_page;
+                        high_pbes_done++;
+                        if (!is_high)
+                                low_pages_for_highmem--;
+                        do {
+                                orig_high_pfn = memory_bm_next_pfn(pageset1_map, 0);
+                                BUG_ON(orig_high_pfn == BM_END_OF_MAP);
+                                orig_page = pfn_to_page(orig_high_pfn);
+                        } while (!PageHighMem(orig_page) ||
+                                        PagePageset1Copy(orig_page));
+
+                        this_high_pbe->orig_address = (void *) orig_high_pfn;
+                        this_high_pbe->address = page;
+                        this_high_pbe->next = NULL;
+                        toi_message(TOI_PAGEDIR, TOI_VERBOSE, 0, "High pbe %d/%d: %p(%d)=>%p",
+                                        high_page, high_offset, page, orig_high_pfn, orig_page);
+                        if (last_high_pbe_page != high_pbe_page) {
+                                *last_high_pbe_ptr =
+                                        (struct pbe *) high_pbe_page;
+                                if (last_high_pbe_page) {
+                                        kunmap(last_high_pbe_page);
+                                        high_page++;
+                                        high_offset = 0;
+                                } else
+                                        high_offset++;
+                                last_high_pbe_page = high_pbe_page;
+                        } else {
+                                *last_high_pbe_ptr = this_high_pbe;
+                                high_offset++;
+                        }
+                        last_high_pbe_ptr = &this_high_pbe->next;
+                        this_high_pbe = get_next_pbe(&high_pbe_page,
+                                        this_high_pbe, 1);
+                        if (IS_ERR(this_high_pbe)) {
+                                printk(KERN_INFO
+                                                "This high pbe is an error.\n");
+                                return -ENOMEM;
+                        }
+                } else {
+                        struct page *orig_page;
+                        low_pbes_done++;
+                        do {
+                                orig_low_pfn = memory_bm_next_pfn(pageset1_map, 0);
+                                BUG_ON(orig_low_pfn == BM_END_OF_MAP);
+                                orig_page = pfn_to_page(orig_low_pfn);
+                        } while (PageHighMem(orig_page) ||
+                                        PagePageset1Copy(orig_page));
+
+                        this_low_pbe->orig_address = page_address(orig_page);
+                        this_low_pbe->address = page_address(page);
+                        this_low_pbe->next = NULL;
+                        toi_message(TOI_PAGEDIR, TOI_VERBOSE, 0, "Low pbe %d/%d: %p(%d)=>%p",
+                                        low_page, low_offset, this_low_pbe->orig_address,
+                                        orig_low_pfn, this_low_pbe->address);
+                        TOI_TRACE_DEBUG(orig_low_pfn, "LoadAddresses (%d/%d): %p=>%p", low_page, low_offset, this_low_pbe->orig_address, this_low_pbe->address);
+                        *last_low_pbe_ptr = this_low_pbe;
+                        last_low_pbe_ptr = &this_low_pbe->next;
+                        this_low_pbe = get_next_pbe(&low_pbe_page,
+                                        this_low_pbe, 0);
+                        if (low_pbe_page != last_low_pbe_page) {
+                                if (last_low_pbe_page) {
+                                        low_page++;
+                                        low_offset = 0;
+                                } else {
+                                    low_offset++;
+                                }
+                                last_low_pbe_page = low_pbe_page;
+                        } else
+                                low_offset++;
+                        if (IS_ERR(this_low_pbe)) {
+                                printk(KERN_INFO "this_low_pbe is an error.\n");
+                                return -ENOMEM;
+                        }
+                }
+        }
+
+        if (high_pbe_page)
+                kunmap(high_pbe_page);
+
+        if (last_high_pbe_page != high_pbe_page) {
+                if (last_high_pbe_page)
+                        kunmap(last_high_pbe_page);
+                toi__free_page(29, high_pbe_page);
+        }
+
+        free_conflicting_pages();
+
+out:
+        return result;
+}
+
+int add_boot_kernel_data_pbe(void)
+{
+        this_low_pbe->address = (char *) __toi_get_nonconflicting_page();
+        if (!this_low_pbe->address) {
+                printk(KERN_INFO "Failed to get bkd atomic restore buffer.");
+                return -ENOMEM;
+        }
+
+        toi_bkd.size = sizeof(toi_bkd);
+        memcpy(this_low_pbe->address, &toi_bkd, sizeof(toi_bkd));
+
+        *last_low_pbe_ptr = this_low_pbe;
+        this_low_pbe->orig_address = (char *) boot_kernel_data_buffer;
+        this_low_pbe->next = NULL;
+        return 0;
+}
diff --git a/kernel/power/tuxonice_pagedir.h b/kernel/power/tuxonice_pagedir.h
new file mode 100644
index 000000000..046535918
--- /dev/null
+++ b/kernel/power/tuxonice_pagedir.h
@@ -0,0 +1,50 @@
+/*
+ * kernel/power/tuxonice_pagedir.h
+ *
+ * Copyright (C) 2006-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * Declarations for routines for handling pagesets.
+ */
+
+#ifndef KERNEL_POWER_PAGEDIR_H
+#define KERNEL_POWER_PAGEDIR_H
+
+/* Pagedir
+ *
+ * Contains the metadata for a set of pages saved in the image.
+ */
+
+struct pagedir {
+        int id;
+        unsigned long size;
+#ifdef CONFIG_HIGHMEM
+        unsigned long size_high;
+#endif
+};
+
+#ifdef CONFIG_HIGHMEM
+#define get_highmem_size(pagedir) (pagedir.size_high)
+#define set_highmem_size(pagedir, sz) do { pagedir.size_high = sz; } while (0)
+#define inc_highmem_size(pagedir) do { pagedir.size_high++; } while (0)
+#define get_lowmem_size(pagedir) (pagedir.size - pagedir.size_high)
+#else
+#define get_highmem_size(pagedir) (0)
+#define set_highmem_size(pagedir, sz) do { } while (0)
+#define inc_highmem_size(pagedir) do { } while (0)
+#define get_lowmem_size(pagedir) (pagedir.size)
+#endif
+
+extern struct pagedir pagedir1, pagedir2;
+
+extern void toi_copy_pageset1(void);
+
+extern int toi_get_pageset1_load_addresses(void);
+
+extern unsigned long __toi_get_nonconflicting_page(void);
+struct page *___toi_get_nonconflicting_page(int can_be_highmem);
+
+extern void toi_reset_alt_image_pageset2_pfn(void);
+extern int add_boot_kernel_data_pbe(void);
+#endif
diff --git a/kernel/power/tuxonice_pageflags.c b/kernel/power/tuxonice_pageflags.c
new file mode 100644
index 000000000..0fe92edd7
--- /dev/null
+++ b/kernel/power/tuxonice_pageflags.c
@@ -0,0 +1,18 @@
+/*
+ * kernel/power/tuxonice_pageflags.c
+ *
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * Routines for serialising and relocating pageflags in which we
+ * store our image metadata.
+ */
+
+#include "tuxonice_pageflags.h"
+#include "power.h"
+
+int toi_pageflags_space_needed(void)
+{
+        return memory_bm_space_needed(pageset1_map);
+}
diff --git a/kernel/power/tuxonice_pageflags.h b/kernel/power/tuxonice_pageflags.h
new file mode 100644
index 000000000..ddeeaf1e7
--- /dev/null
+++ b/kernel/power/tuxonice_pageflags.h
@@ -0,0 +1,106 @@
+/*
+ * kernel/power/tuxonice_pageflags.h
+ *
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ */
+
+#ifndef KERNEL_POWER_TUXONICE_PAGEFLAGS_H
+#define KERNEL_POWER_TUXONICE_PAGEFLAGS_H
+
+struct  memory_bitmap;
+void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free);
+void memory_bm_clear(struct memory_bitmap *bm);
+
+int mem_bm_set_bit_check(struct memory_bitmap *bm, int index, unsigned long pfn);
+void memory_bm_set_bit(struct memory_bitmap *bm, int index, unsigned long pfn);
+unsigned long memory_bm_next_pfn(struct memory_bitmap *bm, int index);
+unsigned long memory_bm_next_pfn_index(struct memory_bitmap *bm, int index);
+void memory_bm_position_reset(struct memory_bitmap *bm);
+void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free);
+int toi_alloc_bitmap(struct memory_bitmap **bm);
+void toi_free_bitmap(struct memory_bitmap **bm);
+void memory_bm_clear(struct memory_bitmap *bm);
+void memory_bm_clear_bit(struct memory_bitmap *bm, int index, unsigned long pfn);
+void memory_bm_set_bit(struct memory_bitmap *bm, int index, unsigned long pfn);
+int memory_bm_test_bit(struct memory_bitmap *bm, int index, unsigned long pfn);
+int memory_bm_test_bit_index(struct memory_bitmap *bm, int index, unsigned long pfn);
+void memory_bm_clear_bit_index(struct memory_bitmap *bm, int index, unsigned long pfn);
+
+struct toi_module_ops;
+int memory_bm_write(struct memory_bitmap *bm, int (*rw_chunk)
+        (int rw, struct toi_module_ops *owner, char *buffer, int buffer_size));
+int memory_bm_read(struct memory_bitmap *bm, int (*rw_chunk)
+        (int rw, struct toi_module_ops *owner, char *buffer, int buffer_size));
+int memory_bm_space_needed(struct memory_bitmap *bm);
+
+extern struct memory_bitmap *pageset1_map;
+extern struct memory_bitmap *pageset1_copy_map;
+extern struct memory_bitmap *pageset2_map;
+extern struct memory_bitmap *page_resave_map;
+extern struct memory_bitmap *io_map;
+extern struct memory_bitmap *nosave_map;
+extern struct memory_bitmap *free_map;
+extern struct memory_bitmap *compare_map;
+
+#define PagePageset1(page) \
+        (pageset1_map && memory_bm_test_bit(pageset1_map, smp_processor_id(), page_to_pfn(page)))
+#define SetPagePageset1(page) \
+        (memory_bm_set_bit(pageset1_map, smp_processor_id(), page_to_pfn(page)))
+#define ClearPagePageset1(page) \
+        (memory_bm_clear_bit(pageset1_map, smp_processor_id(), page_to_pfn(page)))
+
+#define PagePageset1Copy(page) \
+        (memory_bm_test_bit(pageset1_copy_map, smp_processor_id(), page_to_pfn(page)))
+#define SetPagePageset1Copy(page) \
+        (memory_bm_set_bit(pageset1_copy_map, smp_processor_id(), page_to_pfn(page)))
+#define ClearPagePageset1Copy(page) \
+        (memory_bm_clear_bit(pageset1_copy_map, smp_processor_id(), page_to_pfn(page)))
+
+#define PagePageset2(page) \
+        (memory_bm_test_bit(pageset2_map, smp_processor_id(), page_to_pfn(page)))
+#define SetPagePageset2(page) \
+        (memory_bm_set_bit(pageset2_map, smp_processor_id(), page_to_pfn(page)))
+#define ClearPagePageset2(page) \
+        (memory_bm_clear_bit(pageset2_map, smp_processor_id(), page_to_pfn(page)))
+
+#define PageWasRW(page) \
+        (memory_bm_test_bit(pageset2_map, smp_processor_id(), page_to_pfn(page)))
+#define SetPageWasRW(page) \
+        (memory_bm_set_bit(pageset2_map, smp_processor_id(), page_to_pfn(page)))
+#define ClearPageWasRW(page) \
+        (memory_bm_clear_bit(pageset2_map, smp_processor_id(), page_to_pfn(page)))
+
+#define PageResave(page) (page_resave_map ? \
+        memory_bm_test_bit(page_resave_map, smp_processor_id(), page_to_pfn(page)) : 0)
+#define SetPageResave(page) \
+        (memory_bm_set_bit(page_resave_map, smp_processor_id(), page_to_pfn(page)))
+#define ClearPageResave(page) \
+        (memory_bm_clear_bit(page_resave_map, smp_processor_id(), page_to_pfn(page)))
+
+#define PageNosave(page) (nosave_map ? \
+        memory_bm_test_bit(nosave_map, smp_processor_id(), page_to_pfn(page)) : 0)
+#define SetPageNosave(page) \
+        (mem_bm_set_bit_check(nosave_map, smp_processor_id(), page_to_pfn(page)))
+#define ClearPageNosave(page) \
+        (memory_bm_clear_bit(nosave_map, smp_processor_id(), page_to_pfn(page)))
+
+#define PageNosaveFree(page) (free_map ? \
+                memory_bm_test_bit(free_map, smp_processor_id(), page_to_pfn(page)) : 0)
+#define SetPageNosaveFree(page) \
+        (memory_bm_set_bit(free_map, smp_processor_id(), page_to_pfn(page)))
+#define ClearPageNosaveFree(page) \
+        (memory_bm_clear_bit(free_map, smp_processor_id(), page_to_pfn(page)))
+
+#define PageCompareChanged(page) (compare_map ? \
+                memory_bm_test_bit(compare_map, smp_processor_id(), page_to_pfn(page)) : 0)
+#define SetPageCompareChanged(page) \
+        (memory_bm_set_bit(compare_map, smp_processor_id(), page_to_pfn(page)))
+#define ClearPageCompareChanged(page) \
+        (memory_bm_clear_bit(compare_map, smp_processor_id(), page_to_pfn(page)))
+
+extern void save_pageflags(struct memory_bitmap *pagemap);
+extern int load_pageflags(struct memory_bitmap *pagemap);
+extern int toi_pageflags_space_needed(void);
+#endif
diff --git a/kernel/power/tuxonice_power_off.c b/kernel/power/tuxonice_power_off.c
new file mode 100644
index 000000000..7c78773cf
--- /dev/null
+++ b/kernel/power/tuxonice_power_off.c
@@ -0,0 +1,286 @@
+/*
+ * kernel/power/tuxonice_power_off.c
+ *
+ * Copyright (C) 2006-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * Support for powering down.
+ */
+
+#include <linux/device.h>
+#include <linux/suspend.h>
+#include <linux/mm.h>
+#include <linux/pm.h>
+#include <linux/reboot.h>
+#include <linux/cpu.h>
+#include <linux/console.h>
+#include <linux/fs.h>
+#include "tuxonice.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_power_off.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_io.h"
+
+unsigned long toi_poweroff_method; /* 0 - Kernel power off */
+
+static int wake_delay;
+static char lid_state_file[256], wake_alarm_dir[256];
+static struct file *lid_file, *alarm_file, *epoch_file;
+static int post_wake_state = -1;
+
+static int did_suspend_to_both;
+
+/*
+ * __toi_power_down
+ * Functionality   : Powers down or reboots the computer once the image
+ *                   has been written to disk.
+ * Key Assumptions : Able to reboot/power down via code called or that
+ *                   the warning emitted if the calls fail will be visible
+ *                   to the user (ie printk resumes devices).
+ */
+
+static void __toi_power_down(int method)
+{
+        int error;
+
+        toi_cond_pause(1, test_action_state(TOI_REBOOT) ? "Ready to reboot." :
+                        "Powering down.");
+
+        if (test_result_state(TOI_ABORTED))
+                goto out;
+
+        if (test_action_state(TOI_REBOOT))
+                kernel_restart(NULL);
+
+        switch (method) {
+        case 0:
+                break;
+        case 3:
+                /*
+                 * Re-read the overwritten part of pageset2 to make post-resume
+                 * faster.
+                 */
+                if (read_pageset2(1))
+                        panic("Attempt to reload pagedir 2 failed. "
+                                        "Try rebooting.");
+
+                pm_prepare_console();
+
+                error = pm_notifier_call_chain(PM_SUSPEND_PREPARE);
+                if (!error) {
+                        pm_restore_gfp_mask();
+                        error = suspend_devices_and_enter(PM_SUSPEND_MEM);
+                        pm_restrict_gfp_mask();
+                        if (!error)
+                                did_suspend_to_both = 1;
+                }
+                pm_notifier_call_chain(PM_POST_SUSPEND);
+                pm_restore_console();
+
+                /* Success - we're now post-resume-from-ram */
+                if (did_suspend_to_both)
+                        return;
+
+                /* Failed to suspend to ram - do normal power off */
+                break;
+        case 4:
+                /*
+                 * If succeeds, doesn't return. If fails, do a simple
+                 * powerdown.
+                 */
+                hibernation_platform_enter();
+                break;
+        case 5:
+                /* Historic entry only now */
+                break;
+        }
+
+        if (method && method != 5)
+                toi_cond_pause(1,
+                        "Falling back to alternate power off method.");
+
+        if (test_result_state(TOI_ABORTED))
+                goto out;
+
+        if (pm_power_off)
+            kernel_power_off();
+        kernel_halt();
+        toi_cond_pause(1, "Powerdown failed.");
+        while (1)
+                cpu_relax();
+
+out:
+        if (read_pageset2(1))
+                panic("Attempt to reload pagedir 2 failed. Try rebooting.");
+        return;
+}
+
+#define CLOSE_FILE(file) \
+        if (file) { \
+                filp_close(file, NULL); file = NULL; \
+        }
+
+static void powerdown_cleanup(int toi_or_resume)
+{
+        if (!toi_or_resume)
+                return;
+
+        CLOSE_FILE(lid_file);
+        CLOSE_FILE(alarm_file);
+        CLOSE_FILE(epoch_file);
+}
+
+static void open_file(char *format, char *arg, struct file **var, int mode,
+                char *desc)
+{
+        char buf[256];
+
+        if (strlen(arg)) {
+                sprintf(buf, format, arg);
+                *var = filp_open(buf, mode, 0);
+                if (IS_ERR(*var) || !*var) {
+                        printk(KERN_INFO "Failed to open %s file '%s' (%p).\n",
+                                desc, buf, *var);
+                        *var = NULL;
+                }
+        }
+}
+
+static int powerdown_init(int toi_or_resume)
+{
+        if (!toi_or_resume)
+                return 0;
+
+        did_suspend_to_both = 0;
+
+        open_file("/proc/acpi/button/%s/state", lid_state_file, &lid_file,
+                        O_RDONLY, "lid");
+
+        if (strlen(wake_alarm_dir)) {
+                open_file("/sys/class/rtc/%s/wakealarm", wake_alarm_dir,
+                                &alarm_file, O_WRONLY, "alarm");
+
+                open_file("/sys/class/rtc/%s/since_epoch", wake_alarm_dir,
+                                &epoch_file, O_RDONLY, "epoch");
+        }
+
+        return 0;
+}
+
+static int lid_closed(void)
+{
+        char array[25];
+        ssize_t size;
+        loff_t pos = 0;
+
+        if (!lid_file)
+                return 0;
+
+        size = vfs_read(lid_file, (char __user *) array, 25, &pos);
+        if ((int) size < 1) {
+                printk(KERN_INFO "Failed to read lid state file (%d).\n",
+                        (int) size);
+                return 0;
+        }
+
+        if (!strcmp(array, "state:      closed\n"))
+                return 1;
+
+        return 0;
+}
+
+static void write_alarm_file(int value)
+{
+        ssize_t size;
+        char buf[40];
+        loff_t pos = 0;
+
+        if (!alarm_file)
+                return;
+
+        sprintf(buf, "%d\n", value);
+
+        size = vfs_write(alarm_file, (char __user *)buf, strlen(buf), &pos);
+
+        if (size < 0)
+                printk(KERN_INFO "Error %d writing alarm value %s.\n",
+                                (int) size, buf);
+}
+
+/**
+ * toi_check_resleep: See whether to powerdown again after waking.
+ *
+ * After waking, check whether we should powerdown again in a (usually
+ * different) way. We only do this if the lid switch is still closed.
+ */
+void toi_check_resleep(void)
+{
+        /* We only return if we suspended to ram and woke. */
+        if (lid_closed() && post_wake_state >= 0)
+                __toi_power_down(post_wake_state);
+}
+
+void toi_power_down(void)
+{
+        if (alarm_file && wake_delay) {
+                char array[25];
+                loff_t pos = 0;
+                size_t size = vfs_read(epoch_file, (char __user *) array, 25,
+                                &pos);
+
+                if (((int) size) < 1)
+                        printk(KERN_INFO "Failed to read epoch file (%d).\n",
+                                        (int) size);
+                else {
+                        unsigned long since_epoch;
+                        if (!kstrtoul(array, 0, &since_epoch)) {
+                                /* Clear any wakeup time. */
+                                write_alarm_file(0);
+
+                                /* Set new wakeup time. */
+                                write_alarm_file(since_epoch + wake_delay);
+                        }
+                }
+        }
+
+        __toi_power_down(toi_poweroff_method);
+
+        toi_check_resleep();
+}
+
+static struct toi_sysfs_data sysfs_params[] = {
+#if defined(CONFIG_ACPI)
+        SYSFS_STRING("lid_file", SYSFS_RW, lid_state_file, 256, 0, NULL),
+        SYSFS_INT("wake_delay", SYSFS_RW, &wake_delay, 0, INT_MAX, 0, NULL),
+        SYSFS_STRING("wake_alarm_dir", SYSFS_RW, wake_alarm_dir, 256, 0, NULL),
+        SYSFS_INT("post_wake_state", SYSFS_RW, &post_wake_state, -1, 5, 0,
+                        NULL),
+        SYSFS_UL("powerdown_method", SYSFS_RW, &toi_poweroff_method, 0, 5, 0),
+        SYSFS_INT("did_suspend_to_both", SYSFS_READONLY, &did_suspend_to_both,
+                0, 0, 0, NULL)
+#endif
+};
+
+static struct toi_module_ops powerdown_ops = {
+        .type                                = MISC_HIDDEN_MODULE,
+        .name                                = "poweroff",
+        .initialise                        = powerdown_init,
+        .cleanup                        = powerdown_cleanup,
+        .directory                        = "[ROOT]",
+        .module                                = THIS_MODULE,
+        .sysfs_data                        = sysfs_params,
+        .num_sysfs_entries                = sizeof(sysfs_params) /
+                sizeof(struct toi_sysfs_data),
+};
+
+int toi_poweroff_init(void)
+{
+        return toi_register_module(&powerdown_ops);
+}
+
+void toi_poweroff_exit(void)
+{
+        toi_unregister_module(&powerdown_ops);
+}
diff --git a/kernel/power/tuxonice_power_off.h b/kernel/power/tuxonice_power_off.h
new file mode 100644
index 000000000..6e1d8bb39
--- /dev/null
+++ b/kernel/power/tuxonice_power_off.h
@@ -0,0 +1,24 @@
+/*
+ * kernel/power/tuxonice_power_off.h
+ *
+ * Copyright (C) 2006-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * Support for the powering down.
+ */
+
+int toi_pm_state_finish(void);
+void toi_power_down(void);
+extern unsigned long toi_poweroff_method;
+int toi_poweroff_init(void);
+void toi_poweroff_exit(void);
+void toi_check_resleep(void);
+
+extern int platform_begin(int platform_mode);
+extern int platform_pre_snapshot(int platform_mode);
+extern void platform_leave(int platform_mode);
+extern void platform_end(int platform_mode);
+extern void platform_finish(int platform_mode);
+extern int platform_pre_restore(int platform_mode);
+extern void platform_restore_cleanup(int platform_mode);
diff --git a/kernel/power/tuxonice_prepare_image.c b/kernel/power/tuxonice_prepare_image.c
new file mode 100644
index 000000000..a10d62080
--- /dev/null
+++ b/kernel/power/tuxonice_prepare_image.c
@@ -0,0 +1,1080 @@
+/*
+ * kernel/power/tuxonice_prepare_image.c
+ *
+ * Copyright (C) 2003-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * We need to eat memory until we can:
+ * 1. Perform the save without changing anything (RAM_NEEDED < #pages)
+ * 2. Fit it all in available space (toiActiveAllocator->available_space() >=
+ *    main_storage_needed())
+ * 3. Reload the pagedir and pageset1 to places that don't collide with their
+ *    final destinations, not knowing to what extent the resumed kernel will
+ *    overlap with the one loaded at boot time. I think the resumed kernel
+ *    should overlap completely, but I don't want to rely on this as it is
+ *    an unproven assumption. We therefore assume there will be no overlap at
+ *    all (worse case).
+ * 4. Meet the user's requested limit (if any) on the size of the image.
+ *    The limit is in MB, so pages/256 (assuming 4K pages).
+ *
+ */
+
+#include <linux/highmem.h>
+#include <linux/freezer.h>
+#include <linux/hardirq.h>
+#include <linux/mmzone.h>
+#include <linux/console.h>
+#include <linux/tuxonice.h>
+
+#include "tuxonice_pageflags.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_io.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_prepare_image.h"
+#include "tuxonice.h"
+#include "tuxonice_extent.h"
+#include "tuxonice_checksum.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice_alloc.h"
+#include "tuxonice_atomic_copy.h"
+#include "tuxonice_builtin.h"
+
+static unsigned long num_nosave, main_storage_allocated, storage_limit,
+            header_storage_needed;
+unsigned long extra_pd1_pages_allowance =
+        CONFIG_TOI_DEFAULT_EXTRA_PAGES_ALLOWANCE;
+long image_size_limit = CONFIG_TOI_DEFAULT_IMAGE_SIZE_LIMIT;
+static int no_ps2_needed;
+
+struct attention_list {
+        struct task_struct *task;
+        struct attention_list *next;
+};
+
+static struct attention_list *attention_list;
+
+#define PAGESET1 0
+#define PAGESET2 1
+
+void free_attention_list(void)
+{
+        struct attention_list *last = NULL;
+
+        while (attention_list) {
+                last = attention_list;
+                attention_list = attention_list->next;
+                toi_kfree(6, last, sizeof(*last));
+        }
+}
+
+static int build_attention_list(void)
+{
+        int i, task_count = 0;
+        struct task_struct *p;
+        struct attention_list *next;
+
+        /*
+         * Count all userspace process (with task->mm) marked PF_NOFREEZE.
+         */
+        toi_read_lock_tasklist();
+        for_each_process(p)
+                if ((p->flags & PF_NOFREEZE) || p == current)
+                        task_count++;
+        toi_read_unlock_tasklist();
+
+        /*
+         * Allocate attention list structs.
+         */
+        for (i = 0; i < task_count; i++) {
+                struct attention_list *this =
+                        toi_kzalloc(6, sizeof(struct attention_list),
+                                        TOI_WAIT_GFP);
+                if (!this) {
+                        printk(KERN_INFO "Failed to allocate slab for "
+                                        "attention list.\n");
+                        free_attention_list();
+                        return 1;
+                }
+                this->next = NULL;
+                if (attention_list)
+                        this->next = attention_list;
+                attention_list = this;
+        }
+
+        next = attention_list;
+        toi_read_lock_tasklist();
+        for_each_process(p)
+                if ((p->flags & PF_NOFREEZE) || p == current) {
+                        next->task = p;
+                        next = next->next;
+                }
+        toi_read_unlock_tasklist();
+        return 0;
+}
+
+static void pageset2_full(void)
+{
+        struct zone *zone;
+        struct page *page;
+        unsigned long flags;
+        int i;
+
+        toi_trace_index++;
+
+        for_each_populated_zone(zone) {
+                spin_lock_irqsave(&zone->lru_lock, flags);
+                for_each_lru(i) {
+                        if (!zone_page_state(zone, NR_LRU_BASE + i))
+                                continue;
+
+                        list_for_each_entry(page, &zone->lruvec.lists[i], lru) {
+                                struct address_space *mapping;
+
+                                mapping = page_mapping(page);
+                                if (!mapping || !mapping->host ||
+                                    !(mapping->host->i_flags & S_ATOMIC_COPY)) {
+                                    if (PageTOI_RO(page) && test_result_state(TOI_KEPT_IMAGE)) {
+                                        TOI_TRACE_DEBUG(page_to_pfn(page), "_Pageset2 unmodified.");
+                                    } else {
+                                        TOI_TRACE_DEBUG(page_to_pfn(page), "_Pageset2 pageset2_full.");
+                                        SetPagePageset2(page);
+                                    }
+                                }
+                        }
+                }
+                spin_unlock_irqrestore(&zone->lru_lock, flags);
+        }
+}
+
+/*
+ * toi_mark_task_as_pageset
+ * Functionality   : Marks all the saveable pages belonging to a given process
+ *                      as belonging to a particular pageset.
+ */
+
+static void toi_mark_task_as_pageset(struct task_struct *t, int pageset2)
+{
+        struct vm_area_struct *vma;
+        struct mm_struct *mm;
+
+        mm = t->active_mm;
+
+        if (!mm || !mm->mmap)
+                return;
+
+        toi_trace_index++;
+
+        if (!irqs_disabled())
+                down_read(&mm->mmap_sem);
+
+        for (vma = mm->mmap; vma; vma = vma->vm_next) {
+                unsigned long posn;
+
+                if (!vma->vm_start ||
+                    vma->vm_flags & VM_PFNMAP)
+                        continue;
+
+                for (posn = vma->vm_start; posn < vma->vm_end;
+                                posn += PAGE_SIZE) {
+                        struct page *page = follow_page(vma, posn, 0);
+                        struct address_space *mapping;
+
+                        if (!page || !pfn_valid(page_to_pfn(page)))
+                                continue;
+
+                        mapping = page_mapping(page);
+                        if (mapping && mapping->host &&
+                            mapping->host->i_flags & S_ATOMIC_COPY && pageset2)
+                                continue;
+
+                        if (PageTOI_RO(page) && test_result_state(TOI_KEPT_IMAGE)) {
+                                TOI_TRACE_DEBUG(page_to_pfn(page), "_Unmodified %d", pageset2 ? 1 : 2);
+                                continue;
+                        }
+
+                        if (pageset2) {
+                                TOI_TRACE_DEBUG(page_to_pfn(page), "_MarkTaskAsPageset 1");
+                                SetPagePageset2(page);
+                        } else {
+                                TOI_TRACE_DEBUG(page_to_pfn(page), "_MarkTaskAsPageset 2");
+                                ClearPagePageset2(page);
+                                SetPagePageset1(page);
+                        }
+                }
+        }
+
+        if (!irqs_disabled())
+                up_read(&mm->mmap_sem);
+}
+
+static void mark_tasks(int pageset)
+{
+        struct task_struct *p;
+
+        toi_read_lock_tasklist();
+        for_each_process(p) {
+                if (!p->mm)
+                        continue;
+
+                if (p->flags & PF_KTHREAD)
+                        continue;
+
+                toi_mark_task_as_pageset(p, pageset);
+        }
+        toi_read_unlock_tasklist();
+
+}
+
+/* mark_pages_for_pageset2
+ *
+ * Description:        Mark unshared pages in processes not needed for hibernate as
+ *                 being able to be written out in a separate pagedir.
+ *                 HighMem pages are simply marked as pageset2. They won't be
+ *                 needed during hibernate.
+ */
+
+static void toi_mark_pages_for_pageset2(void)
+{
+        struct attention_list *this = attention_list;
+
+        memory_bm_clear(pageset2_map);
+
+        if (test_action_state(TOI_NO_PAGESET2) || no_ps2_needed)
+                return;
+
+        if (test_action_state(TOI_PAGESET2_FULL))
+                pageset2_full();
+        else
+                mark_tasks(PAGESET2);
+
+        /*
+         * Because the tasks in attention_list are ones related to hibernating,
+         * we know that they won't go away under us.
+         */
+
+        while (this) {
+                if (!test_result_state(TOI_ABORTED))
+                        toi_mark_task_as_pageset(this->task, PAGESET1);
+                this = this->next;
+        }
+}
+
+/*
+ * The atomic copy of pageset1 is stored in pageset2 pages.
+ * But if pageset1 is larger (normally only just after boot),
+ * we need to allocate extra pages to store the atomic copy.
+ * The following data struct and functions are used to handle
+ * the allocation and freeing of that memory.
+ */
+
+static unsigned long extra_pages_allocated;
+
+struct extras {
+        struct page *page;
+        int order;
+        struct extras *next;
+};
+
+static struct extras *extras_list;
+
+/* toi_free_extra_pagedir_memory
+ *
+ * Description:        Free previously allocated extra pagedir memory.
+ */
+void toi_free_extra_pagedir_memory(void)
+{
+        /* Free allocated pages */
+        while (extras_list) {
+                struct extras *this = extras_list;
+                int i;
+
+                extras_list = this->next;
+
+                for (i = 0; i < (1 << this->order); i++)
+                        ClearPageNosave(this->page + i);
+
+                toi_free_pages(9, this->page, this->order);
+                toi_kfree(7, this, sizeof(*this));
+        }
+
+        extra_pages_allocated = 0;
+}
+
+/* toi_allocate_extra_pagedir_memory
+ *
+ * Description:        Allocate memory for making the atomic copy of pagedir1 in the
+ *                 case where it is bigger than pagedir2.
+ * Arguments:        int        num_to_alloc: Number of extra pages needed.
+ * Result:        int.         Number of extra pages we now have allocated.
+ */
+static int toi_allocate_extra_pagedir_memory(int extra_pages_needed)
+{
+        int j, order, num_to_alloc = extra_pages_needed - extra_pages_allocated;
+        gfp_t flags = TOI_ATOMIC_GFP;
+
+        if (num_to_alloc < 1)
+                return 0;
+
+        order = fls(num_to_alloc);
+        if (order >= MAX_ORDER)
+                order = MAX_ORDER - 1;
+
+        while (num_to_alloc) {
+                struct page *newpage;
+                unsigned long virt;
+                struct extras *extras_entry;
+
+                while ((1 << order) > num_to_alloc)
+                        order--;
+
+                extras_entry = (struct extras *) toi_kzalloc(7,
+                        sizeof(struct extras), TOI_ATOMIC_GFP);
+
+                if (!extras_entry)
+                        return extra_pages_allocated;
+
+                virt = toi_get_free_pages(9, flags, order);
+                while (!virt && order) {
+                        order--;
+                        virt = toi_get_free_pages(9, flags, order);
+                }
+
+                if (!virt) {
+                        toi_kfree(7, extras_entry, sizeof(*extras_entry));
+                        return extra_pages_allocated;
+                }
+
+                newpage = virt_to_page(virt);
+
+                extras_entry->page = newpage;
+                extras_entry->order = order;
+                extras_entry->next = extras_list;
+
+                extras_list = extras_entry;
+
+                for (j = 0; j < (1 << order); j++) {
+                        SetPageNosave(newpage + j);
+                        SetPagePageset1Copy(newpage + j);
+                }
+
+                extra_pages_allocated += (1 << order);
+                num_to_alloc -= (1 << order);
+        }
+
+        return extra_pages_allocated;
+}
+
+/*
+ * real_nr_free_pages: Count pcp pages for a zone type or all zones
+ * (-1 for all, otherwise zone_idx() result desired).
+ */
+unsigned long real_nr_free_pages(unsigned long zone_idx_mask)
+{
+        struct zone *zone;
+        int result = 0, cpu;
+
+        /* PCP lists */
+        for_each_populated_zone(zone) {
+                if (!(zone_idx_mask & (1 << zone_idx(zone))))
+                        continue;
+
+                for_each_online_cpu(cpu) {
+                        struct per_cpu_pageset *pset =
+                                per_cpu_ptr(zone->pageset, cpu);
+                        struct per_cpu_pages *pcp = &pset->pcp;
+                        result += pcp->count;
+                }
+
+                result += zone_page_state(zone, NR_FREE_PAGES);
+        }
+        return result;
+}
+
+/*
+ * Discover how much extra memory will be required by the drivers
+ * when they're asked to hibernate. We can then ensure that amount
+ * of memory is available when we really want it.
+ */
+static void get_extra_pd1_allowance(void)
+{
+        unsigned long orig_num_free = real_nr_free_pages(all_zones_mask), final;
+
+        toi_prepare_status(CLEAR_BAR, "Finding allowance for drivers.");
+
+        if (toi_go_atomic(PMSG_FREEZE, 1))
+                return;
+
+        final = real_nr_free_pages(all_zones_mask);
+        toi_end_atomic(ATOMIC_ALL_STEPS, 1, 0);
+
+        extra_pd1_pages_allowance = (orig_num_free > final) ?
+                orig_num_free - final + MIN_EXTRA_PAGES_ALLOWANCE :
+                MIN_EXTRA_PAGES_ALLOWANCE;
+}
+
+/*
+ * Amount of storage needed, possibly taking into account the
+ * expected compression ratio and possibly also ignoring our
+ * allowance for extra pages.
+ */
+static unsigned long main_storage_needed(int use_ecr,
+                int ignore_extra_pd1_allow)
+{
+        return (pagedir1.size + pagedir2.size +
+          (ignore_extra_pd1_allow ? 0 : extra_pd1_pages_allowance)) *
+         (use_ecr ? toi_expected_compression_ratio() : 100) / 100;
+}
+
+/*
+ * Storage needed for the image header, in bytes until the return.
+ */
+unsigned long get_header_storage_needed(void)
+{
+        unsigned long bytes = sizeof(struct toi_header) +
+                        toi_header_storage_for_modules() +
+                        toi_pageflags_space_needed() +
+                        fs_info_space_needed();
+
+        return DIV_ROUND_UP(bytes, PAGE_SIZE);
+}
+
+/*
+ * When freeing memory, pages from either pageset might be freed.
+ *
+ * When seeking to free memory to be able to hibernate, for every ps1 page
+ * freed, we need 2 less pages for the atomic copy because there is one less
+ * page to copy and one more page into which data can be copied.
+ *
+ * Freeing ps2 pages saves us nothing directly. No more memory is available
+ * for the atomic copy. Indirectly, a ps1 page might be freed (slab?), but
+ * that's too much work to figure out.
+ *
+ * => ps1_to_free functions
+ *
+ * Of course if we just want to reduce the image size, because of storage
+ * limitations or an image size limit either ps will do.
+ *
+ * => any_to_free function
+ */
+
+static unsigned long lowpages_usable_for_highmem_copy(void)
+{
+        unsigned long needed = get_lowmem_size(pagedir1) +
+                        extra_pd1_pages_allowance + MIN_FREE_RAM +
+                        toi_memory_for_modules(0),
+                available = get_lowmem_size(pagedir2) +
+                         real_nr_free_low_pages() + extra_pages_allocated;
+
+        return available > needed ? available - needed : 0;
+}
+
+static unsigned long highpages_ps1_to_free(void)
+{
+        unsigned long need = get_highmem_size(pagedir1),
+                      available = get_highmem_size(pagedir2) +
+                              real_nr_free_high_pages() +
+                              lowpages_usable_for_highmem_copy();
+
+        return need > available ? DIV_ROUND_UP(need - available, 2) : 0;
+}
+
+static unsigned long lowpages_ps1_to_free(void)
+{
+        unsigned long needed = get_lowmem_size(pagedir1) +
+                        extra_pd1_pages_allowance + MIN_FREE_RAM +
+                        toi_memory_for_modules(0),
+                available = get_lowmem_size(pagedir2) +
+                         real_nr_free_low_pages() + extra_pages_allocated;
+
+        return needed > available ? DIV_ROUND_UP(needed - available, 2) : 0;
+}
+
+static unsigned long current_image_size(void)
+{
+        return pagedir1.size + pagedir2.size + header_storage_needed;
+}
+
+static unsigned long storage_still_required(void)
+{
+        unsigned long needed = main_storage_needed(1, 1);
+        return needed > storage_limit ? needed - storage_limit : 0;
+}
+
+static unsigned long ram_still_required(void)
+{
+        unsigned long needed = MIN_FREE_RAM + toi_memory_for_modules(0) +
+                2 * extra_pd1_pages_allowance,
+                  available = real_nr_free_low_pages() + extra_pages_allocated;
+        return needed > available ? needed - available : 0;
+}
+
+unsigned long any_to_free(int use_image_size_limit)
+{
+        int use_soft_limit = use_image_size_limit && image_size_limit > 0;
+        unsigned long current_size = current_image_size(),
+                      soft_limit = use_soft_limit ? (image_size_limit << 8) : 0,
+                      to_free = use_soft_limit ? (current_size > soft_limit ?
+                                      current_size - soft_limit : 0) : 0,
+                      storage_limit = storage_still_required(),
+                      ram_limit = ram_still_required(),
+                      first_max = max(to_free, storage_limit);
+
+        return max(first_max, ram_limit);
+}
+
+static int need_pageset2(void)
+{
+        return (real_nr_free_low_pages() + extra_pages_allocated -
+                2 * extra_pd1_pages_allowance - MIN_FREE_RAM -
+                 toi_memory_for_modules(0) - pagedir1.size) < pagedir2.size;
+}
+
+/* amount_needed
+ *
+ * Calculates the amount by which the image size needs to be reduced to meet
+ * our constraints.
+ */
+static unsigned long amount_needed(int use_image_size_limit)
+{
+        return max(highpages_ps1_to_free() + lowpages_ps1_to_free(),
+                        any_to_free(use_image_size_limit));
+}
+
+static int image_not_ready(int use_image_size_limit)
+{
+        toi_message(TOI_EAT_MEMORY, TOI_LOW, 1,
+                "Amount still needed (%lu) > 0:%u,"
+                " Storage allocd: %lu < %lu: %u.\n",
+                        amount_needed(use_image_size_limit),
+                        (amount_needed(use_image_size_limit) > 0),
+                        main_storage_allocated,
+                        main_storage_needed(1, 1),
+                        main_storage_allocated < main_storage_needed(1, 1));
+
+        toi_cond_pause(0, NULL);
+
+        return (amount_needed(use_image_size_limit) > 0) ||
+                 main_storage_allocated < main_storage_needed(1, 1);
+}
+
+static void display_failure_reason(int tries_exceeded)
+{
+        unsigned long storage_required = storage_still_required(),
+            ram_required = ram_still_required(),
+            high_ps1 = highpages_ps1_to_free(),
+            low_ps1 = lowpages_ps1_to_free();
+
+        printk(KERN_INFO "Failed to prepare the image because...\n");
+
+        if (!storage_limit) {
+                printk(KERN_INFO "- You need some storage available to be "
+                                "able to hibernate.\n");
+                return;
+        }
+
+        if (tries_exceeded)
+                printk(KERN_INFO "- The maximum number of iterations was "
+                                "reached without successfully preparing the "
+                                "image.\n");
+
+        if (storage_required) {
+                printk(KERN_INFO " - We need at least %lu pages of storage "
+                                "(ignoring the header), but only have %lu.\n",
+                                main_storage_needed(1, 1),
+                                main_storage_allocated);
+                set_abort_result(TOI_INSUFFICIENT_STORAGE);
+        }
+
+        if (ram_required) {
+                printk(KERN_INFO " - We need %lu more free pages of low "
+                                "memory.\n", ram_required);
+                printk(KERN_INFO "     Minimum free     : %8d\n", MIN_FREE_RAM);
+                printk(KERN_INFO "   + Reqd. by modules : %8lu\n",
+                                toi_memory_for_modules(0));
+                printk(KERN_INFO "   + 2 * extra allow  : %8lu\n",
+                                2 * extra_pd1_pages_allowance);
+                printk(KERN_INFO "   - Currently free   : %8lu\n",
+                                real_nr_free_low_pages());
+                printk(KERN_INFO "   - Pages allocd     : %8lu\n",
+                                extra_pages_allocated);
+                printk(KERN_INFO "                      : ========\n");
+                printk(KERN_INFO "     Still needed     : %8lu\n",
+                                ram_required);
+
+                /* Print breakdown of memory needed for modules */
+                toi_memory_for_modules(1);
+                set_abort_result(TOI_UNABLE_TO_FREE_ENOUGH_MEMORY);
+        }
+
+        if (high_ps1) {
+                printk(KERN_INFO "- We need to free %lu highmem pageset 1 "
+                                "pages.\n", high_ps1);
+                set_abort_result(TOI_UNABLE_TO_FREE_ENOUGH_MEMORY);
+        }
+
+        if (low_ps1) {
+                printk(KERN_INFO " - We need to free %ld lowmem pageset 1 "
+                                "pages.\n", low_ps1);
+                set_abort_result(TOI_UNABLE_TO_FREE_ENOUGH_MEMORY);
+        }
+}
+
+static void display_stats(int always, int sub_extra_pd1_allow)
+{
+        char buffer[255];
+        snprintf(buffer, 254,
+                "Free:%lu(%lu). Sets:%lu(%lu),%lu(%lu). "
+                "Nosave:%lu-%lu=%lu. Storage:%lu/%lu(%lu=>%lu). "
+                "Needed:%lu,%lu,%lu(%u,%lu,%lu,%ld) (PS2:%s)\n",
+
+                /* Free */
+                real_nr_free_pages(all_zones_mask),
+                real_nr_free_low_pages(),
+
+                /* Sets */
+                pagedir1.size, pagedir1.size - get_highmem_size(pagedir1),
+                pagedir2.size, pagedir2.size - get_highmem_size(pagedir2),
+
+                /* Nosave */
+                num_nosave, extra_pages_allocated,
+                num_nosave - extra_pages_allocated,
+
+                /* Storage */
+                main_storage_allocated,
+                storage_limit,
+                main_storage_needed(1, sub_extra_pd1_allow),
+                main_storage_needed(1, 1),
+
+                /* Needed */
+                lowpages_ps1_to_free(), highpages_ps1_to_free(),
+                any_to_free(1),
+                MIN_FREE_RAM, toi_memory_for_modules(0),
+                extra_pd1_pages_allowance,
+                image_size_limit,
+
+                need_pageset2() ? "yes" : "no");
+
+        if (always)
+                printk("%s", buffer);
+        else
+                toi_message(TOI_EAT_MEMORY, TOI_MEDIUM, 1, buffer);
+}
+
+/* flag_image_pages
+ *
+ * This routine generates our lists of pages to be stored in each
+ * pageset. Since we store the data using extents, and adding new
+ * extents might allocate a new extent page, this routine may well
+ * be called more than once.
+ */
+static void flag_image_pages(int atomic_copy)
+{
+        int num_free = 0, num_unmodified = 0;
+        unsigned long loop;
+        struct zone *zone;
+
+        pagedir1.size = 0;
+        pagedir2.size = 0;
+
+        set_highmem_size(pagedir1, 0);
+        set_highmem_size(pagedir2, 0);
+
+        num_nosave = 0;
+        toi_trace_index++;
+
+        memory_bm_clear(pageset1_map);
+
+        toi_generate_free_page_map();
+
+        /*
+         * Pages not to be saved are marked Nosave irrespective of being
+         * reserved.
+         */
+        for_each_populated_zone(zone) {
+                int highmem = is_highmem(zone);
+
+                for (loop = 0; loop < zone->spanned_pages; loop++) {
+                        unsigned long pfn = zone->zone_start_pfn + loop;
+                        struct page *page;
+                        int chunk_size;
+
+                        if (!pfn_valid(pfn)) {
+                            TOI_TRACE_DEBUG(pfn, "_Flag Invalid");
+                            continue;
+                        }
+
+                        chunk_size = toi_size_of_free_region(zone, pfn);
+                        if (chunk_size) {
+                            unsigned long y;
+                            for (y = pfn; y < pfn + chunk_size; y++) {
+                                page = pfn_to_page(y);
+                                TOI_TRACE_DEBUG(y, "_Flag Free");
+                                ClearPagePageset1(page);
+                                ClearPagePageset2(page);
+                            }
+                                num_free += chunk_size;
+                                loop += chunk_size - 1;
+                                continue;
+                        }
+
+                        page = pfn_to_page(pfn);
+
+                        if (PageNosave(page)) {
+                            char *desc = PagePageset1Copy(page) ? "Pageset1Copy" : "NoSave";
+                            TOI_TRACE_DEBUG(pfn, "_Flag %s", desc);
+                            num_nosave++;
+                            continue;
+                        }
+
+                        page = highmem ? saveable_highmem_page(zone, pfn) :
+                                saveable_page(zone, pfn);
+
+                        if (!page) {
+                                TOI_TRACE_DEBUG(pfn, "_Flag Nosave2");
+                                num_nosave++;
+                                continue;
+                        }
+
+                        if (PageTOI_RO(page) && test_result_state(TOI_KEPT_IMAGE)) {
+                            TOI_TRACE_DEBUG(pfn, "_Unmodified");
+                            num_unmodified++;
+                            continue;
+                        }
+
+                        if (PagePageset2(page)) {
+                                pagedir2.size++;
+                                TOI_TRACE_DEBUG(pfn, "_Flag PS2");
+                                if (PageHighMem(page))
+                                        inc_highmem_size(pagedir2);
+                                else
+                                        SetPagePageset1Copy(page);
+                                if (PageResave(page)) {
+                                        SetPagePageset1(page);
+                                        ClearPagePageset1Copy(page);
+                                        pagedir1.size++;
+                                        if (PageHighMem(page))
+                                                inc_highmem_size(pagedir1);
+                                }
+                        } else {
+                                pagedir1.size++;
+                                TOI_TRACE_DEBUG(pfn, "_Flag PS1");
+                                SetPagePageset1(page);
+                                if (PageHighMem(page))
+                                        inc_highmem_size(pagedir1);
+                        }
+                }
+        }
+
+        if (!atomic_copy)
+                toi_message(TOI_EAT_MEMORY, TOI_MEDIUM, 0,
+                        "Count data pages: Set1 (%d) + Set2 (%d) + Nosave (%ld)"
+                                    " + Unmodified (%d) + NumFree (%d) = %d.\n",
+                        pagedir1.size, pagedir2.size, num_nosave, num_unmodified,
+                        num_free, pagedir1.size + pagedir2.size + num_nosave + num_free);
+}
+
+void toi_recalculate_image_contents(int atomic_copy)
+{
+        memory_bm_clear(pageset1_map);
+        if (!atomic_copy) {
+                unsigned long pfn;
+                memory_bm_position_reset(pageset2_map);
+                for (pfn = memory_bm_next_pfn(pageset2_map, 0);
+                                pfn != BM_END_OF_MAP;
+                                pfn = memory_bm_next_pfn(pageset2_map, 0))
+                        ClearPagePageset1Copy(pfn_to_page(pfn));
+                /* Need to call this before getting pageset1_size! */
+                toi_mark_pages_for_pageset2();
+        }
+        memory_bm_position_reset(pageset2_map);
+        flag_image_pages(atomic_copy);
+
+        if (!atomic_copy) {
+                storage_limit = toiActiveAllocator->storage_available();
+                display_stats(0, 0);
+        }
+}
+
+int try_allocate_extra_memory(void)
+{
+        unsigned long wanted = pagedir1.size +  extra_pd1_pages_allowance -
+                get_lowmem_size(pagedir2);
+        if (wanted > extra_pages_allocated) {
+                unsigned long got = toi_allocate_extra_pagedir_memory(wanted);
+                if (wanted < got) {
+                        toi_message(TOI_EAT_MEMORY, TOI_LOW, 1,
+                                "Want %d extra pages for pageset1, got %d.\n",
+                                wanted, got);
+                        return 1;
+                }
+        }
+        return 0;
+}
+
+/* update_image
+ *
+ * Allocate [more] memory and storage for the image.
+ */
+static void update_image(int ps2_recalc)
+{
+        int old_header_req;
+        unsigned long seek;
+
+        if (try_allocate_extra_memory())
+                return;
+
+        if (ps2_recalc)
+                goto recalc;
+
+        thaw_kernel_threads();
+
+        /*
+         * Allocate remaining storage space, if possible, up to the
+         * maximum we know we'll need. It's okay to allocate the
+         * maximum if the writer is the swapwriter, but
+         * we don't want to grab all available space on an NFS share.
+         * We therefore ignore the expected compression ratio here,
+         * thereby trying to allocate the maximum image size we could
+         * need (assuming compression doesn't expand the image), but
+         * don't complain if we can't get the full amount we're after.
+         */
+
+        do {
+                int result;
+
+                old_header_req = header_storage_needed;
+                toiActiveAllocator->reserve_header_space(header_storage_needed);
+
+                /* How much storage is free with the reservation applied? */
+                storage_limit = toiActiveAllocator->storage_available();
+                seek = min(storage_limit, main_storage_needed(0, 0));
+
+                result = toiActiveAllocator->allocate_storage(seek);
+                if (result)
+                        printk("Failed to allocate storage (%d).\n", result);
+
+                main_storage_allocated =
+                        toiActiveAllocator->storage_allocated();
+
+                /* Need more header because more storage allocated? */
+                header_storage_needed = get_header_storage_needed();
+
+        } while (header_storage_needed > old_header_req);
+
+        if (freeze_kernel_threads())
+                set_abort_result(TOI_FREEZING_FAILED);
+
+recalc:
+        toi_recalculate_image_contents(0);
+}
+
+/* attempt_to_freeze
+ *
+ * Try to freeze processes.
+ */
+
+static int attempt_to_freeze(void)
+{
+        int result;
+
+        /* Stop processes before checking again */
+        toi_prepare_status(CLEAR_BAR, "Freezing processes & syncing "
+                        "filesystems.");
+        result = freeze_processes();
+
+        if (result)
+                set_abort_result(TOI_FREEZING_FAILED);
+
+        result = freeze_kernel_threads();
+
+        if (result)
+                set_abort_result(TOI_FREEZING_FAILED);
+
+        return result;
+}
+
+/* eat_memory
+ *
+ * Try to free some memory, either to meet hard or soft constraints on the image
+ * characteristics.
+ *
+ * Hard constraints:
+ * - Pageset1 must be < half of memory;
+ * - We must have enough memory free at resume time to have pageset1
+ *   be able to be loaded in pages that don't conflict with where it has to
+ *   be restored.
+ * Soft constraints
+ * - User specificied image size limit.
+ */
+static void eat_memory(void)
+{
+        unsigned long amount_wanted = 0;
+        int did_eat_memory = 0;
+
+        /*
+         * Note that if we have enough storage space and enough free memory, we
+         * may exit without eating anything. We give up when the last 10
+         * iterations ate no extra pages because we're not going to get much
+         * more anyway, but the few pages we get will take a lot of time.
+         *
+         * We freeze processes before beginning, and then unfreeze them if we
+         * need to eat memory until we think we have enough. If our attempts
+         * to freeze fail, we give up and abort.
+         */
+
+        amount_wanted = amount_needed(1);
+
+        switch (image_size_limit) {
+        case -1: /* Don't eat any memory */
+                if (amount_wanted > 0) {
+                        set_abort_result(TOI_WOULD_EAT_MEMORY);
+                        return;
+                }
+                break;
+        case -2:  /* Free caches only */
+                drop_pagecache();
+                toi_recalculate_image_contents(0);
+                amount_wanted = amount_needed(1);
+                break;
+        default:
+                break;
+        }
+
+        if (amount_wanted > 0 && !test_result_state(TOI_ABORTED) &&
+                        image_size_limit != -1) {
+                unsigned long request = amount_wanted;
+                unsigned long high_req = max(highpages_ps1_to_free(),
+                                any_to_free(1));
+                unsigned long low_req = lowpages_ps1_to_free();
+                unsigned long got = 0;
+
+                toi_prepare_status(CLEAR_BAR,
+                                "Seeking to free %ldMB of memory.",
+                                MB(amount_wanted));
+
+                thaw_kernel_threads();
+
+                /*
+                 * Ask for too many because shrink_memory_mask doesn't
+                 * currently return enough most of the time.
+                 */
+                
+                if (low_req)
+                        got = shrink_memory_mask(low_req, GFP_KERNEL);
+                if (high_req)
+                        shrink_memory_mask(high_req - got, GFP_HIGHUSER);
+
+                did_eat_memory = 1;
+
+                toi_recalculate_image_contents(0);
+
+                amount_wanted = amount_needed(1);
+
+                printk(KERN_DEBUG "Asked shrink_memory_mask for %ld low pages &"
+                                " %ld pages from anywhere, got %ld.\n",
+                                high_req, low_req,
+                                request - amount_wanted);
+
+                toi_cond_pause(0, NULL);
+
+                if (freeze_kernel_threads())
+                        set_abort_result(TOI_FREEZING_FAILED);
+        }
+
+        if (did_eat_memory)
+                toi_recalculate_image_contents(0);
+}
+
+/* toi_prepare_image
+ *
+ * Entry point to the whole image preparation section.
+ *
+ * We do four things:
+ * - Freeze processes;
+ * - Ensure image size constraints are met;
+ * - Complete all the preparation for saving the image,
+ *   including allocation of storage. The only memory
+ *   that should be needed when we're finished is that
+ *   for actually storing the image (and we know how
+ *   much is needed for that because the modules tell
+ *   us).
+ * - Make sure that all dirty buffers are written out.
+ */
+#define MAX_TRIES 2
+int toi_prepare_image(void)
+{
+        int result = 1, tries = 1;
+
+        main_storage_allocated = 0;
+        no_ps2_needed = 0;
+
+        if (attempt_to_freeze())
+                return 1;
+
+        lock_device_hotplug();
+        set_toi_state(TOI_DEVICE_HOTPLUG_LOCKED);
+
+        if (!extra_pd1_pages_allowance)
+                get_extra_pd1_allowance();
+
+        storage_limit = toiActiveAllocator->storage_available();
+
+        if (!storage_limit) {
+                printk(KERN_INFO "No storage available. Didn't try to prepare "
+                                "an image.\n");
+                display_failure_reason(0);
+                set_abort_result(TOI_NOSTORAGE_AVAILABLE);
+                return 1;
+        }
+
+        if (build_attention_list()) {
+                abort_hibernate(TOI_UNABLE_TO_PREPARE_IMAGE,
+                                "Unable to successfully prepare the image.\n");
+                return 1;
+        }
+
+        toi_recalculate_image_contents(0);
+
+        do {
+                toi_prepare_status(CLEAR_BAR,
+                                "Preparing Image. Try %d.", tries);
+
+                eat_memory();
+
+                if (test_result_state(TOI_ABORTED))
+                        break;
+
+                update_image(0);
+
+                tries++;
+
+        } while (image_not_ready(1) && tries <= MAX_TRIES &&
+                        !test_result_state(TOI_ABORTED));
+
+        result = image_not_ready(0);
+
+        /* TODO: Handle case where need to remove existing image and resave
+         * instead of adding to incremental image. */
+
+        if (!test_result_state(TOI_ABORTED)) {
+                if (result) {
+                        display_stats(1, 0);
+                        display_failure_reason(tries > MAX_TRIES);
+                        abort_hibernate(TOI_UNABLE_TO_PREPARE_IMAGE,
+                                "Unable to successfully prepare the image.\n");
+                } else {
+                        /* Pageset 2 needed? */
+                        if (!need_pageset2() &&
+                                  test_action_state(TOI_NO_PS2_IF_UNNEEDED)) {
+                                no_ps2_needed = 1;
+                                toi_recalculate_image_contents(0);
+                                update_image(1);
+                        }
+
+                        toi_cond_pause(1, "Image preparation complete.");
+                }
+        }
+
+        return result ? result : allocate_checksum_pages();
+}
diff --git a/kernel/power/tuxonice_prepare_image.h b/kernel/power/tuxonice_prepare_image.h
new file mode 100644
index 000000000..c1508975c
--- /dev/null
+++ b/kernel/power/tuxonice_prepare_image.h
@@ -0,0 +1,38 @@
+/*
+ * kernel/power/tuxonice_prepare_image.h
+ *
+ * Copyright (C) 2003-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ */
+
+#include <asm/sections.h>
+
+extern int toi_prepare_image(void);
+extern void toi_recalculate_image_contents(int storage_available);
+extern unsigned long real_nr_free_pages(unsigned long zone_idx_mask);
+extern long image_size_limit;
+extern void toi_free_extra_pagedir_memory(void);
+extern unsigned long extra_pd1_pages_allowance;
+extern void free_attention_list(void);
+
+#define MIN_FREE_RAM 100
+#define MIN_EXTRA_PAGES_ALLOWANCE 500
+
+#define all_zones_mask ((unsigned long) ((1 << MAX_NR_ZONES) - 1))
+#ifdef CONFIG_HIGHMEM
+#define real_nr_free_high_pages() (real_nr_free_pages(1 << ZONE_HIGHMEM))
+#define real_nr_free_low_pages() (real_nr_free_pages(all_zones_mask - \
+                                                (1 << ZONE_HIGHMEM)))
+#else
+#define real_nr_free_high_pages() (0)
+#define real_nr_free_low_pages() (real_nr_free_pages(all_zones_mask))
+
+/* For eat_memory function */
+#define ZONE_HIGHMEM (MAX_NR_ZONES + 1)
+#endif
+
+unsigned long get_header_storage_needed(void);
+unsigned long any_to_free(int use_image_size_limit);
+int try_allocate_extra_memory(void);
diff --git a/kernel/power/tuxonice_prune.c b/kernel/power/tuxonice_prune.c
new file mode 100644
index 000000000..5bc56d3a1
--- /dev/null
+++ b/kernel/power/tuxonice_prune.c
@@ -0,0 +1,406 @@
+/*
+ * kernel/power/tuxonice_prune.c
+ *
+ * Copyright (C) 2012 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * This file implements a TuxOnIce module that seeks to prune the
+ * amount of data written to disk. It builds a table of hashes
+ * of the uncompressed data, and writes the pfn of the previous page
+ * with the same contents instead of repeating the data when a match
+ * is found.
+ */
+
+#include <linux/suspend.h>
+#include <linux/highmem.h>
+#include <linux/vmalloc.h>
+#include <linux/crypto.h>
+#include <linux/scatterlist.h>
+#include <crypto/hash.h>
+
+#include "tuxonice_builtin.h"
+#include "tuxonice.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice_io.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_alloc.h"
+
+/*
+ * We never write a page bigger than PAGE_SIZE, so use a large number
+ * to indicate that data is a PFN.
+ */
+#define PRUNE_DATA_IS_PFN (PAGE_SIZE + 100)
+
+static unsigned long toi_pruned_pages;
+
+static struct toi_module_ops toi_prune_ops;
+static struct toi_module_ops *next_driver;
+
+static char toi_prune_hash_algo_name[32] = "sha1";
+
+static DEFINE_MUTEX(stats_lock);
+
+struct cpu_context {
+        struct shash_desc desc;
+        char *digest;
+};
+
+#define OUT_BUF_SIZE (2 * PAGE_SIZE)
+
+static DEFINE_PER_CPU(struct cpu_context, contexts);
+
+/*
+ * toi_crypto_prepare
+ *
+ * Prepare to do some work by allocating buffers and transforms.
+ */
+static int toi_prune_crypto_prepare(void)
+{
+        int cpu, ret, digestsize;
+
+        if (!*toi_prune_hash_algo_name) {
+                printk(KERN_INFO "TuxOnIce: Pruning enabled but no "
+                                "hash algorithm set.\n");
+                return 1;
+        }
+
+        for_each_online_cpu(cpu) {
+                struct cpu_context *this = &per_cpu(contexts, cpu);
+                this->desc.tfm = crypto_alloc_shash(toi_prune_hash_algo_name, 0, 0);
+                if (IS_ERR(this->desc.tfm)) {
+                        printk(KERN_INFO "TuxOnIce: Failed to allocate the "
+                                        "%s prune hash algorithm.\n",
+                                        toi_prune_hash_algo_name);
+                        this->desc.tfm = NULL;
+                        return 1;
+                }
+
+                if (!digestsize)
+                        digestsize = crypto_shash_digestsize(this->desc.tfm);
+
+                this->digest = kmalloc(digestsize, GFP_KERNEL);
+                if (!this->digest) {
+                        printk(KERN_INFO "TuxOnIce: Failed to allocate space "
+                                        "for digest output.\n");
+                        crypto_free_shash(this->desc.tfm);
+                        this->desc.tfm = NULL;
+                }
+
+                this->desc.flags = 0;
+
+                ret = crypto_shash_init(&this->desc);
+                if (ret < 0) {
+                        printk(KERN_INFO "TuxOnIce: Failed to initialise the "
+                                        "%s prune hash algorithm.\n",
+                                        toi_prune_hash_algo_name);
+                        kfree(this->digest);
+                        this->digest = NULL;
+                        crypto_free_shash(this->desc.tfm);
+                        this->desc.tfm = NULL;
+                        return 1;
+                }
+        }
+
+        return 0;
+}
+
+static int toi_prune_rw_cleanup(int writing)
+{
+        int cpu;
+
+        for_each_online_cpu(cpu) {
+                struct cpu_context *this = &per_cpu(contexts, cpu);
+                if (this->desc.tfm) {
+                        crypto_free_shash(this->desc.tfm);
+                        this->desc.tfm = NULL;
+                }
+
+                if (this->digest) {
+                        kfree(this->digest);
+                        this->digest = NULL;
+                }
+        }
+
+        return 0;
+}
+
+/*
+ * toi_prune_init
+ */
+
+static int toi_prune_init(int toi_or_resume)
+{
+        if (!toi_or_resume)
+                return 0;
+
+        toi_pruned_pages = 0;
+
+        next_driver = toi_get_next_filter(&toi_prune_ops);
+
+        return next_driver ? 0 : -ECHILD;
+}
+
+/*
+ * toi_prune_rw_init()
+ */
+
+static int toi_prune_rw_init(int rw, int stream_number)
+{
+        if (toi_prune_crypto_prepare()) {
+                printk(KERN_ERR "Failed to initialise prune "
+                                "algorithm.\n");
+                if (rw == READ) {
+                        printk(KERN_INFO "Unable to read the image.\n");
+                        return -ENODEV;
+                } else {
+                        printk(KERN_INFO "Continuing without "
+                                "pruning the image.\n");
+                        toi_prune_ops.enabled = 0;
+                }
+        }
+
+        return 0;
+}
+
+/*
+ * toi_prune_write_page()
+ *
+ * Compress a page of data, buffering output and passing on filled
+ * pages to the next module in the pipeline.
+ *
+ * Buffer_page:        Pointer to a buffer of size PAGE_SIZE, containing
+ * data to be checked.
+ *
+ * Returns:        0 on success. Otherwise the error is that returned by later
+ *                 modules, -ECHILD if we have a broken pipeline or -EIO if
+ *                 zlib errs.
+ */
+static int toi_prune_write_page(unsigned long index, int buf_type,
+                void *buffer_page, unsigned int buf_size)
+{
+        int ret = 0, cpu = smp_processor_id(), write_data = 1;
+        struct cpu_context *ctx = &per_cpu(contexts, cpu);
+        u8* output_buffer = buffer_page;
+        int output_len = buf_size;
+        int out_buf_type = buf_type;
+        void *buffer_start;
+        u32 buf[4];
+
+        if (ctx->desc.tfm) {
+
+                buffer_start = TOI_MAP(buf_type, buffer_page);
+                ctx->len = OUT_BUF_SIZE;
+
+                ret = crypto_shash_digest(&ctx->desc, buffer_start, buf_size, &ctx->digest);
+                if (ret) {
+                        printk(KERN_INFO "TuxOnIce: Failed to calculate digest (%d).\n", ret);
+                } else {
+                        mutex_lock(&stats_lock);
+
+                        toi_pruned_pages++;
+
+                        mutex_unlock(&stats_lock);
+
+                }
+
+                TOI_UNMAP(buf_type, buffer_page);
+        }
+
+        if (write_data)
+                ret = next_driver->write_page(index, out_buf_type,
+                                output_buffer, output_len);
+        else
+                ret = next_driver->write_page(index, out_buf_type,
+                                output_buffer, output_len);
+
+        return ret;
+}
+
+/*
+ * toi_prune_read_page()
+ * @buffer_page: struct page *. Pointer to a buffer of size PAGE_SIZE.
+ *
+ * Retrieve data from later modules or from a previously loaded page and
+ * fill the input buffer.
+ * Zero if successful. Error condition from me or from downstream on failure.
+ */
+static int toi_prune_read_page(unsigned long *index, int buf_type,
+                void *buffer_page, unsigned int *buf_size)
+{
+        int ret, cpu = smp_processor_id();
+        unsigned int len;
+        char *buffer_start;
+        struct cpu_context *ctx = &per_cpu(contexts, cpu);
+
+        if (!ctx->desc.tfm)
+                return next_driver->read_page(index, TOI_PAGE, buffer_page,
+                                buf_size);
+
+        /*
+         * All our reads must be synchronous - we can't handle
+         * data that hasn't been read yet.
+         */
+
+        ret = next_driver->read_page(index, buf_type, buffer_page, &len);
+
+        if (len == PRUNE_DATA_IS_PFN) {
+                buffer_start = kmap(buffer_page);
+        }
+
+        return ret;
+}
+
+/*
+ * toi_prune_print_debug_stats
+ * @buffer: Pointer to a buffer into which the debug info will be printed.
+ * @size: Size of the buffer.
+ *
+ * Print information to be recorded for debugging purposes into a buffer.
+ * Returns: Number of characters written to the buffer.
+ */
+
+static int toi_prune_print_debug_stats(char *buffer, int size)
+{
+        int len;
+
+        /* Output the number of pages pruned. */
+        if (*toi_prune_hash_algo_name)
+                len = scnprintf(buffer, size, "- Compressor is '%s'.\n",
+                                toi_prune_hash_algo_name);
+        else
+                len = scnprintf(buffer, size, "- Compressor is not set.\n");
+
+        if (toi_pruned_pages)
+                len += scnprintf(buffer+len, size - len, "  Pruned "
+                        "%lu pages).\n",
+                  toi_pruned_pages);
+        return len;
+}
+
+/*
+ * toi_prune_memory_needed
+ *
+ * Tell the caller how much memory we need to operate during hibernate/resume.
+ * Returns: Unsigned long. Maximum number of bytes of memory required for
+ * operation.
+ */
+static int toi_prune_memory_needed(void)
+{
+        return 2 * PAGE_SIZE;
+}
+
+static int toi_prune_storage_needed(void)
+{
+        return 2 * sizeof(unsigned long) + 2 * sizeof(int) +
+                strlen(toi_prune_hash_algo_name) + 1;
+}
+
+/*
+ * toi_prune_save_config_info
+ * @buffer: Pointer to a buffer of size PAGE_SIZE.
+ *
+ * Save informaton needed when reloading the image at resume time.
+ * Returns: Number of bytes used for saving our data.
+ */
+static int toi_prune_save_config_info(char *buffer)
+{
+        int len = strlen(toi_prune_hash_algo_name) + 1, offset = 0;
+
+        *((unsigned long *) buffer) = toi_pruned_pages;
+        offset += sizeof(unsigned long);
+        *((int *) (buffer + offset)) = len;
+        offset += sizeof(int);
+        strncpy(buffer + offset, toi_prune_hash_algo_name, len);
+        return offset + len;
+}
+
+/* toi_prune_load_config_info
+ * @buffer: Pointer to the start of the data.
+ * @size: Number of bytes that were saved.
+ *
+ * Description:        Reload information needed for passing back to the
+ * resumed kernel.
+ */
+static void toi_prune_load_config_info(char *buffer, int size)
+{
+        int len, offset = 0;
+
+        toi_pruned_pages = *((unsigned long *) buffer);
+        offset += sizeof(unsigned long);
+        len = *((int *) (buffer + offset));
+        offset += sizeof(int);
+        strncpy(toi_prune_hash_algo_name, buffer + offset, len);
+}
+
+static void toi_prune_pre_atomic_restore(struct toi_boot_kernel_data *bkd)
+{
+        bkd->pruned_pages = toi_pruned_pages;
+}
+
+static void toi_prune_post_atomic_restore(struct toi_boot_kernel_data *bkd)
+{
+        toi_pruned_pages = bkd->pruned_pages;
+}
+
+/*
+ * toi_expected_ratio
+ *
+ * Description:        Returns the expected ratio between data passed into this module
+ *                 and the amount of data output when writing.
+ * Returns:        100 - we have no idea how many pages will be pruned.
+ */
+
+static int toi_prune_expected_ratio(void)
+{
+        return 100;
+}
+
+/*
+ * data for our sysfs entries.
+ */
+static struct toi_sysfs_data sysfs_params[] = {
+        SYSFS_INT("enabled", SYSFS_RW, &toi_prune_ops.enabled, 0, 1, 0,
+                        NULL),
+        SYSFS_STRING("algorithm", SYSFS_RW, toi_prune_hash_algo_name, 31, 0, NULL),
+};
+
+/*
+ * Ops structure.
+ */
+static struct toi_module_ops toi_prune_ops = {
+        .type                        = FILTER_MODULE,
+        .name                        = "prune",
+        .directory                = "prune",
+        .module                        = THIS_MODULE,
+        .initialise                = toi_prune_init,
+        .memory_needed                 = toi_prune_memory_needed,
+        .print_debug_info        = toi_prune_print_debug_stats,
+        .save_config_info        = toi_prune_save_config_info,
+        .load_config_info        = toi_prune_load_config_info,
+        .storage_needed                = toi_prune_storage_needed,
+        .expected_compression        = toi_prune_expected_ratio,
+
+        .pre_atomic_restore        = toi_prune_pre_atomic_restore,
+        .post_atomic_restore        = toi_prune_post_atomic_restore,
+
+        .rw_init                = toi_prune_rw_init,
+        .rw_cleanup                = toi_prune_rw_cleanup,
+
+        .write_page                = toi_prune_write_page,
+        .read_page                = toi_prune_read_page,
+
+        .sysfs_data                = sysfs_params,
+        .num_sysfs_entries        = sizeof(sysfs_params) /
+                sizeof(struct toi_sysfs_data),
+};
+
+/* ---- Registration ---- */
+
+static __init int toi_prune_load(void)
+{
+        return toi_register_module(&toi_prune_ops);
+}
+
+late_initcall(toi_prune_load);
diff --git a/kernel/power/tuxonice_storage.c b/kernel/power/tuxonice_storage.c
new file mode 100644
index 000000000..d8539c275
--- /dev/null
+++ b/kernel/power/tuxonice_storage.c
@@ -0,0 +1,282 @@
+/*
+ * kernel/power/tuxonice_storage.c
+ *
+ * Copyright (C) 2005-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * Routines for talking to a userspace program that manages storage.
+ *
+ * The kernel side:
+ * - starts the userspace program;
+ * - sends messages telling it when to open and close the connection;
+ * - tells it when to quit;
+ *
+ * The user space side:
+ * - passes messages regarding status;
+ *
+ */
+
+#include <linux/suspend.h>
+#include <linux/freezer.h>
+
+#include "tuxonice_sysfs.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_netlink.h"
+#include "tuxonice_storage.h"
+#include "tuxonice_ui.h"
+
+static struct user_helper_data usm_helper_data;
+static struct toi_module_ops usm_ops;
+static int message_received, usm_prepare_count;
+static int storage_manager_last_action, storage_manager_action;
+
+static int usm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+{
+        int type;
+        int *data;
+
+        type = nlh->nlmsg_type;
+
+        /* A control message: ignore them */
+        if (type < NETLINK_MSG_BASE)
+                return 0;
+
+        /* Unknown message: reply with EINVAL */
+        if (type >= USM_MSG_MAX)
+                return -EINVAL;
+
+        /* All operations require privileges, even GET */
+        if (!capable(CAP_NET_ADMIN))
+                return -EPERM;
+
+        /* Only allow one task to receive NOFREEZE privileges */
+        if (type == NETLINK_MSG_NOFREEZE_ME && usm_helper_data.pid != -1)
+                return -EBUSY;
+
+        data = (int *) NLMSG_DATA(nlh);
+
+        switch (type) {
+        case USM_MSG_SUCCESS:
+        case USM_MSG_FAILED:
+                message_received = type;
+                complete(&usm_helper_data.wait_for_process);
+                break;
+        default:
+                printk(KERN_INFO "Storage manager doesn't recognise "
+                                "message %d.\n", type);
+        }
+
+        return 1;
+}
+
+#ifdef CONFIG_NET
+static int activations;
+
+int toi_activate_storage(int force)
+{
+        int tries = 1;
+
+        if (usm_helper_data.pid == -1 || !usm_ops.enabled)
+                return 0;
+
+        message_received = 0;
+        activations++;
+
+        if (activations > 1 && !force)
+                return 0;
+
+        while ((!message_received || message_received == USM_MSG_FAILED) &&
+                        tries < 2) {
+                toi_prepare_status(DONT_CLEAR_BAR, "Activate storage attempt "
+                                "%d.\n", tries);
+
+                init_completion(&usm_helper_data.wait_for_process);
+
+                toi_send_netlink_message(&usm_helper_data,
+                        USM_MSG_CONNECT,
+                        NULL, 0);
+
+                /* Wait 2 seconds for the userspace process to make contact */
+                wait_for_completion_timeout(&usm_helper_data.wait_for_process,
+                                2*HZ);
+
+                tries++;
+        }
+
+        return 0;
+}
+
+int toi_deactivate_storage(int force)
+{
+        if (usm_helper_data.pid == -1 || !usm_ops.enabled)
+                return 0;
+
+        message_received = 0;
+        activations--;
+
+        if (activations && !force)
+                return 0;
+
+        init_completion(&usm_helper_data.wait_for_process);
+
+        toi_send_netlink_message(&usm_helper_data,
+                        USM_MSG_DISCONNECT,
+                        NULL, 0);
+
+        wait_for_completion_timeout(&usm_helper_data.wait_for_process, 2*HZ);
+
+        if (!message_received || message_received == USM_MSG_FAILED) {
+                printk(KERN_INFO "Returning failure disconnecting storage.\n");
+                return 1;
+        }
+
+        return 0;
+}
+#endif
+
+static void storage_manager_simulate(void)
+{
+        printk(KERN_INFO "--- Storage manager simulate ---\n");
+        toi_prepare_usm();
+        schedule();
+        printk(KERN_INFO "--- Activate storage 1 ---\n");
+        toi_activate_storage(1);
+        schedule();
+        printk(KERN_INFO "--- Deactivate storage 1 ---\n");
+        toi_deactivate_storage(1);
+        schedule();
+        printk(KERN_INFO "--- Cleanup usm ---\n");
+        toi_cleanup_usm();
+        schedule();
+        printk(KERN_INFO "--- Storage manager simulate ends ---\n");
+}
+
+static int usm_storage_needed(void)
+{
+        return sizeof(int) + strlen(usm_helper_data.program) + 1;
+}
+
+static int usm_save_config_info(char *buf)
+{
+        int len = strlen(usm_helper_data.program);
+        memcpy(buf, usm_helper_data.program, len + 1);
+        return sizeof(int) + len + 1;
+}
+
+static void usm_load_config_info(char *buf, int size)
+{
+        /* Don't load the saved path if one has already been set */
+        if (usm_helper_data.program[0])
+                return;
+
+        memcpy(usm_helper_data.program, buf + sizeof(int), *((int *) buf));
+}
+
+static int usm_memory_needed(void)
+{
+        /* ball park figure of 32 pages */
+        return 32 * PAGE_SIZE;
+}
+
+/* toi_prepare_usm
+ */
+int toi_prepare_usm(void)
+{
+        usm_prepare_count++;
+
+        if (usm_prepare_count > 1 || !usm_ops.enabled)
+                return 0;
+
+        usm_helper_data.pid = -1;
+
+        if (!*usm_helper_data.program)
+                return 0;
+
+        toi_netlink_setup(&usm_helper_data);
+
+        if (usm_helper_data.pid == -1)
+                printk(KERN_INFO "TuxOnIce Storage Manager wanted, but couldn't"
+                                " start it.\n");
+
+        toi_activate_storage(0);
+
+        return usm_helper_data.pid != -1;
+}
+
+void toi_cleanup_usm(void)
+{
+        usm_prepare_count--;
+
+        if (usm_helper_data.pid > -1 && !usm_prepare_count) {
+                toi_deactivate_storage(0);
+                toi_netlink_close(&usm_helper_data);
+        }
+}
+
+static void storage_manager_activate(void)
+{
+        if (storage_manager_action == storage_manager_last_action)
+                return;
+
+        if (storage_manager_action)
+                toi_prepare_usm();
+        else
+                toi_cleanup_usm();
+
+        storage_manager_last_action = storage_manager_action;
+}
+
+/*
+ * User interface specific /sys/power/tuxonice entries.
+ */
+
+static struct toi_sysfs_data sysfs_params[] = {
+        SYSFS_NONE("simulate_atomic_copy", storage_manager_simulate),
+        SYSFS_INT("enabled", SYSFS_RW, &usm_ops.enabled, 0, 1, 0, NULL),
+        SYSFS_STRING("program", SYSFS_RW, usm_helper_data.program, 254, 0,
+                NULL),
+        SYSFS_INT("activate_storage", SYSFS_RW , &storage_manager_action, 0, 1,
+                        0, storage_manager_activate)
+};
+
+static struct toi_module_ops usm_ops = {
+        .type                                = MISC_MODULE,
+        .name                                = "usm",
+        .directory                        = "storage_manager",
+        .module                                = THIS_MODULE,
+        .storage_needed                        = usm_storage_needed,
+        .save_config_info                = usm_save_config_info,
+        .load_config_info                = usm_load_config_info,
+        .memory_needed                        = usm_memory_needed,
+
+        .sysfs_data                        = sysfs_params,
+        .num_sysfs_entries                = sizeof(sysfs_params) /
+                sizeof(struct toi_sysfs_data),
+};
+
+/* toi_usm_sysfs_init
+ * Description: Boot time initialisation for user interface.
+ */
+int toi_usm_init(void)
+{
+        usm_helper_data.nl = NULL;
+        usm_helper_data.program[0] = '\0';
+        usm_helper_data.pid = -1;
+        usm_helper_data.skb_size = 0;
+        usm_helper_data.pool_limit = 6;
+        usm_helper_data.netlink_id = NETLINK_TOI_USM;
+        usm_helper_data.name = "userspace storage manager";
+        usm_helper_data.rcv_msg = usm_user_rcv_msg;
+        usm_helper_data.interface_version = 2;
+        usm_helper_data.must_init = 0;
+        init_completion(&usm_helper_data.wait_for_process);
+
+        return toi_register_module(&usm_ops);
+}
+
+void toi_usm_exit(void)
+{
+        toi_netlink_close_complete(&usm_helper_data);
+        toi_unregister_module(&usm_ops);
+}
diff --git a/kernel/power/tuxonice_storage.h b/kernel/power/tuxonice_storage.h
new file mode 100644
index 000000000..0189c8888
--- /dev/null
+++ b/kernel/power/tuxonice_storage.h
@@ -0,0 +1,45 @@
+/*
+ * kernel/power/tuxonice_storage.h
+ *
+ * Copyright (C) 2005-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ */
+
+#ifdef CONFIG_NET
+int toi_prepare_usm(void);
+void toi_cleanup_usm(void);
+
+int toi_activate_storage(int force);
+int toi_deactivate_storage(int force);
+extern int toi_usm_init(void);
+extern void toi_usm_exit(void);
+#else
+static inline int toi_usm_init(void) { return 0; }
+static inline void toi_usm_exit(void) { }
+
+static inline int toi_activate_storage(int force)
+{
+        return 0;
+}
+
+static inline int toi_deactivate_storage(int force)
+{
+        return 0;
+}
+
+static inline int toi_prepare_usm(void) { return 0; }
+static inline void toi_cleanup_usm(void) { }
+#endif
+
+enum {
+        USM_MSG_BASE = 0x10,
+
+        /* Kernel -> Userspace */
+        USM_MSG_CONNECT = 0x30,
+        USM_MSG_DISCONNECT = 0x31,
+        USM_MSG_SUCCESS = 0x40,
+        USM_MSG_FAILED = 0x41,
+
+        USM_MSG_MAX,
+};
diff --git a/kernel/power/tuxonice_swap.c b/kernel/power/tuxonice_swap.c
new file mode 100644
index 000000000..9f555c932
--- /dev/null
+++ b/kernel/power/tuxonice_swap.c
@@ -0,0 +1,474 @@
+/*
+ * kernel/power/tuxonice_swap.c
+ *
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * Distributed under GPLv2.
+ *
+ * This file encapsulates functions for usage of swap space as a
+ * backing store.
+ */
+
+#include <linux/suspend.h>
+#include <linux/blkdev.h>
+#include <linux/swapops.h>
+#include <linux/swap.h>
+#include <linux/syscalls.h>
+#include <linux/fs_uuid.h>
+
+#include "tuxonice.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_io.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_extent.h"
+#include "tuxonice_bio.h"
+#include "tuxonice_alloc.h"
+#include "tuxonice_builtin.h"
+
+static struct toi_module_ops toi_swapops;
+
+/* For swapfile automatically swapon/off'd. */
+static char swapfilename[255] = "";
+static int toi_swapon_status;
+
+/* Swap Pages */
+static unsigned long swap_allocated;
+
+static struct sysinfo swapinfo;
+
+static int is_ram_backed(struct swap_info_struct *si)
+{
+        if (!strncmp(si->bdev->bd_disk->disk_name, "ram", 3) ||
+            !strncmp(si->bdev->bd_disk->disk_name, "zram", 4))
+                return 1;
+
+        return 0;
+}
+
+/**
+ * enable_swapfile: Swapon the user specified swapfile prior to hibernating.
+ *
+ * Activate the given swapfile if it wasn't already enabled. Remember whether
+ * we really did swapon it for swapoffing later.
+ */
+static void enable_swapfile(void)
+{
+        int activateswapresult = -EINVAL;
+
+        if (swapfilename[0]) {
+                /* Attempt to swap on with maximum priority */
+                activateswapresult = sys_swapon(swapfilename, 0xFFFF);
+                if (activateswapresult && activateswapresult != -EBUSY)
+                        printk(KERN_ERR "TuxOnIce: The swapfile/partition "
+                                "specified by /sys/power/tuxonice/swap/swapfile"
+                                " (%s) could not be turned on (error %d). "
+                                "Attempting to continue.\n",
+                                swapfilename, activateswapresult);
+                if (!activateswapresult)
+                        toi_swapon_status = 1;
+        }
+}
+
+/**
+ * disable_swapfile: Swapoff any file swaponed at the start of the cycle.
+ *
+ * If we did successfully swapon a file at the start of the cycle, swapoff
+ * it now (finishing up).
+ */
+static void disable_swapfile(void)
+{
+        if (!toi_swapon_status)
+                return;
+
+        sys_swapoff(swapfilename);
+        toi_swapon_status = 0;
+}
+
+static int add_blocks_to_extent_chain(struct toi_bdev_info *chain,
+                unsigned long start, unsigned long end)
+{
+        if (test_action_state(TOI_TEST_BIO))
+                toi_message(TOI_IO, TOI_VERBOSE, 0, "Adding extent %lu-%lu to "
+                                "chain %p.", start << chain->bmap_shift,
+                                end << chain->bmap_shift, chain);
+
+        return toi_add_to_extent_chain(&chain->blocks, start, end);
+}
+
+
+static int get_main_pool_phys_params(struct toi_bdev_info *chain)
+{
+        struct hibernate_extent *extentpointer = NULL;
+        unsigned long address, extent_min = 0, extent_max = 0;
+        int empty = 1;
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "get main pool phys params for "
+                        "chain %d.", chain->allocator_index);
+
+        if (!chain->allocations.first)
+                return 0;
+
+        if (chain->blocks.first)
+                toi_put_extent_chain(&chain->blocks);
+
+        toi_extent_for_each(&chain->allocations, extentpointer, address) {
+                swp_entry_t swap_address = (swp_entry_t) { address };
+                struct block_device *bdev;
+                sector_t new_sector = map_swap_entry(swap_address, &bdev);
+
+                if (empty) {
+                        empty = 0;
+                        extent_min = extent_max = new_sector;
+                        continue;
+                }
+
+                if (new_sector == extent_max + 1) {
+                        extent_max++;
+                        continue;
+                }
+
+                if (add_blocks_to_extent_chain(chain, extent_min, extent_max)) {
+                        printk(KERN_ERR "Out of memory while making block "
+                                        "chains.\n");
+                        return -ENOMEM;
+                }
+
+                extent_min = new_sector;
+                extent_max = new_sector;
+        }
+
+        if (!empty &&
+            add_blocks_to_extent_chain(chain, extent_min, extent_max)) {
+                printk(KERN_ERR "Out of memory while making block chains.\n");
+                return -ENOMEM;
+        }
+
+        return 0;
+}
+
+/*
+ * Like si_swapinfo, except that we don't include ram backed swap (compcache!)
+ * and don't need to use the spinlocks (userspace is stopped when this
+ * function is called).
+ */
+void si_swapinfo_no_compcache(void)
+{
+        unsigned int i;
+
+        si_swapinfo(&swapinfo);
+        swapinfo.freeswap = 0;
+        swapinfo.totalswap = 0;
+
+        for (i = 0; i < MAX_SWAPFILES; i++) {
+                struct swap_info_struct *si = get_swap_info_struct(i);
+                if (si && (si->flags & SWP_WRITEOK) && !is_ram_backed(si)) {
+                        swapinfo.totalswap += si->inuse_pages;
+                        swapinfo.freeswap += si->pages - si->inuse_pages;
+                }
+        }
+}
+/*
+ * We can't just remember the value from allocation time, because other
+ * processes might have allocated swap in the mean time.
+ */
+static unsigned long toi_swap_storage_available(void)
+{
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "In toi_swap_storage_available.");
+        si_swapinfo_no_compcache();
+        return swapinfo.freeswap + swap_allocated;
+}
+
+static int toi_swap_initialise(int starting_cycle)
+{
+        if (!starting_cycle)
+                return 0;
+
+        enable_swapfile();
+        return 0;
+}
+
+static void toi_swap_cleanup(int ending_cycle)
+{
+        if (!ending_cycle)
+                return;
+
+        disable_swapfile();
+}
+
+static void toi_swap_free_storage(struct toi_bdev_info *chain)
+{
+        /* Free swap entries */
+        struct hibernate_extent *extentpointer;
+        unsigned long extentvalue;
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "Freeing storage for chain %p.",
+                        chain);
+
+        swap_allocated -= chain->allocations.size;
+        toi_extent_for_each(&chain->allocations, extentpointer, extentvalue)
+                swap_free((swp_entry_t) { extentvalue });
+
+        toi_put_extent_chain(&chain->allocations);
+}
+
+static void free_swap_range(unsigned long min, unsigned long max)
+{
+        int j;
+
+        for (j = min; j <= max; j++)
+                swap_free((swp_entry_t) { j });
+        swap_allocated -= (max - min + 1);
+}
+
+/*
+ * Allocation of a single swap type. Swap priorities are handled at the higher
+ * level.
+ */
+static int toi_swap_allocate_storage(struct toi_bdev_info *chain,
+                unsigned long request)
+{
+        unsigned long gotten = 0;
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "  Swap allocate storage: Asked to"
+                        " allocate %lu pages from device %d.", request,
+                        chain->allocator_index);
+
+        while (gotten < request) {
+                swp_entry_t start, end;
+                if (0) {
+                    /* Broken at the moment for SSDs */
+                    get_swap_range_of_type(chain->allocator_index, &start, &end,
+                            request - gotten + 1);
+                } else {
+                    start = end = get_swap_page_of_type(chain->allocator_index);
+                }
+                if (start.val) {
+                        int added = end.val - start.val + 1;
+                        if (toi_add_to_extent_chain(&chain->allocations,
+                                                start.val, end.val)) {
+                                printk(KERN_INFO "Failed to allocate extent for "
+                                        "%lu-%lu.\n", start.val, end.val);
+                                free_swap_range(start.val, end.val);
+                                break;
+                        }
+                        gotten += added;
+                        swap_allocated += added;
+                } else
+                        break;
+        }
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "  Allocated %lu pages.", gotten);
+        return gotten;
+}
+
+static int toi_swap_register_storage(void)
+{
+        int i, result = 0;
+
+        toi_message(TOI_IO, TOI_VERBOSE, 0, "toi_swap_register_storage.");
+        for (i = 0; i < MAX_SWAPFILES; i++) {
+                struct swap_info_struct *si = get_swap_info_struct(i);
+                struct toi_bdev_info *devinfo;
+                unsigned char *p;
+                unsigned char buf[256];
+                struct fs_info *fs_info;
+
+                if (!si || !(si->flags & SWP_WRITEOK) || is_ram_backed(si))
+                        continue;
+
+                devinfo = toi_kzalloc(39, sizeof(struct toi_bdev_info),
+                                GFP_ATOMIC);
+                if (!devinfo) {
+                        printk("Failed to allocate devinfo struct for swap "
+                                        "device %d.\n", i);
+                        return -ENOMEM;
+                }
+
+                devinfo->bdev = si->bdev;
+                devinfo->allocator = &toi_swapops;
+                devinfo->allocator_index = i;
+
+                fs_info = fs_info_from_block_dev(si->bdev);
+                if (fs_info && !IS_ERR(fs_info)) {
+                        memcpy(devinfo->uuid, &fs_info->uuid, 16);
+                        free_fs_info(fs_info);
+                } else
+                        result = (int) PTR_ERR(fs_info);
+
+                if (!fs_info)
+                        printk("fs_info from block dev returned %d.\n", result);
+                devinfo->dev_t = si->bdev->bd_dev;
+                devinfo->prio = si->prio;
+                devinfo->bmap_shift = 3;
+                devinfo->blocks_per_page = 1;
+
+                p = d_path(&si->swap_file->f_path, buf, sizeof(buf));
+                sprintf(devinfo->name, "swap on %s", p);
+
+                toi_message(TOI_IO, TOI_VERBOSE, 0, "Registering swap storage:"
+                                " Device %d (%lx), prio %d.", i,
+                                (unsigned long) devinfo->dev_t, devinfo->prio);
+                toi_bio_ops.register_storage(devinfo);
+        }
+
+        return 0;
+}
+
+static unsigned long toi_swap_free_unused_storage(struct toi_bdev_info *chain, unsigned long used)
+{
+    struct hibernate_extent *extentpointer = NULL;
+    unsigned long extentvalue;
+    unsigned long i = 0, first_freed = 0;
+
+    toi_extent_for_each(&chain->allocations, extentpointer, extentvalue) {
+        i++;
+        if (i > used) {
+            swap_free((swp_entry_t) { extentvalue });
+            if (!first_freed)
+                first_freed = extentvalue;
+        }
+    }
+
+    return first_freed;
+}
+
+/*
+ * workspace_size
+ *
+ * Description:
+ * Returns the number of bytes of RAM needed for this
+ * code to do its work. (Used when calculating whether
+ * we have enough memory to be able to hibernate & resume).
+ *
+ */
+static int toi_swap_memory_needed(void)
+{
+        return 1;
+}
+
+/*
+ * Print debug info
+ *
+ * Description:
+ */
+static int toi_swap_print_debug_stats(char *buffer, int size)
+{
+        int len = 0;
+
+        len = scnprintf(buffer, size, "- Swap Allocator enabled.\n");
+        if (swapfilename[0])
+                len += scnprintf(buffer+len, size-len,
+                        "  Attempting to automatically swapon: %s.\n",
+                        swapfilename);
+
+        si_swapinfo_no_compcache();
+
+        len += scnprintf(buffer+len, size-len,
+                        "  Swap available for image: %lu pages.\n",
+                        swapinfo.freeswap + swap_allocated);
+
+        return len;
+}
+
+static int header_locations_read_sysfs(const char *page, int count)
+{
+        int i, printedpartitionsmessage = 0, len = 0, haveswap = 0;
+        struct inode *swapf = NULL;
+        int zone;
+        char *path_page = (char *) toi_get_free_page(10, GFP_KERNEL);
+        char *path, *output = (char *) page;
+        int path_len;
+
+        if (!page)
+                return 0;
+
+        for (i = 0; i < MAX_SWAPFILES; i++) {
+                struct swap_info_struct *si =  get_swap_info_struct(i);
+
+                if (!si || !(si->flags & SWP_WRITEOK))
+                        continue;
+
+                if (S_ISBLK(si->swap_file->f_mapping->host->i_mode)) {
+                        haveswap = 1;
+                        if (!printedpartitionsmessage) {
+                                len += sprintf(output + len,
+                                        "For swap partitions, simply use the "
+                                        "format: resume=swap:/dev/hda1.\n");
+                                printedpartitionsmessage = 1;
+                        }
+                } else {
+                        path_len = 0;
+
+                        path = d_path(&si->swap_file->f_path, path_page,
+                                        PAGE_SIZE);
+                        path_len = snprintf(path_page, PAGE_SIZE, "%s", path);
+
+                        haveswap = 1;
+                        swapf = si->swap_file->f_mapping->host;
+                        zone = bmap(swapf, 0);
+                        if (!zone) {
+                                len += sprintf(output + len,
+                                        "Swapfile %s has been corrupted. Reuse"
+                                        " mkswap on it and try again.\n",
+                                        path_page);
+                        } else {
+                                char name_buffer[BDEVNAME_SIZE];
+                                len += sprintf(output + len,
+                                        "For swapfile `%s`,"
+                                        " use resume=swap:/dev/%s:0x%x.\n",
+                                        path_page,
+                                        bdevname(si->bdev, name_buffer),
+                                        zone << (swapf->i_blkbits - 9));
+                        }
+                }
+        }
+
+        if (!haveswap)
+                len = sprintf(output, "You need to turn on swap partitions "
+                                "before examining this file.\n");
+
+        toi_free_page(10, (unsigned long) path_page);
+        return len;
+}
+
+static struct toi_sysfs_data sysfs_params[] = {
+        SYSFS_STRING("swapfilename", SYSFS_RW, swapfilename, 255, 0, NULL),
+        SYSFS_CUSTOM("headerlocations", SYSFS_READONLY,
+                        header_locations_read_sysfs, NULL, 0, NULL),
+        SYSFS_INT("enabled", SYSFS_RW, &toi_swapops.enabled, 0, 1, 0,
+                        attempt_to_parse_resume_device2),
+};
+
+static struct toi_bio_allocator_ops toi_bio_swapops = {
+        .register_storage                        = toi_swap_register_storage,
+        .storage_available                        = toi_swap_storage_available,
+        .allocate_storage                        = toi_swap_allocate_storage,
+        .bmap                                        = get_main_pool_phys_params,
+        .free_storage                                = toi_swap_free_storage,
+        .free_unused_storage                    = toi_swap_free_unused_storage,
+};
+
+static struct toi_module_ops toi_swapops = {
+        .type                                        = BIO_ALLOCATOR_MODULE,
+        .name                                        = "swap storage",
+        .directory                                = "swap",
+        .module                                        = THIS_MODULE,
+        .memory_needed                                = toi_swap_memory_needed,
+        .print_debug_info                        = toi_swap_print_debug_stats,
+        .initialise                                = toi_swap_initialise,
+        .cleanup                                = toi_swap_cleanup,
+        .bio_allocator_ops                        = &toi_bio_swapops,
+
+        .sysfs_data                = sysfs_params,
+        .num_sysfs_entries        = sizeof(sysfs_params) /
+                sizeof(struct toi_sysfs_data),
+};
+
+/* ---- Registration ---- */
+static __init int toi_swap_load(void)
+{
+        return toi_register_module(&toi_swapops);
+}
+
+late_initcall(toi_swap_load);
diff --git a/kernel/power/tuxonice_sysfs.c b/kernel/power/tuxonice_sysfs.c
new file mode 100644
index 000000000..77f36dbeb
--- /dev/null
+++ b/kernel/power/tuxonice_sysfs.c
@@ -0,0 +1,333 @@
+/*
+ * kernel/power/tuxonice_sysfs.c
+ *
+ * Copyright (C) 2002-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * This file contains support for sysfs entries for tuning TuxOnIce.
+ *
+ * We have a generic handler that deals with the most common cases, and
+ * hooks for special handlers to use.
+ */
+
+#include <linux/suspend.h>
+
+#include "tuxonice_sysfs.h"
+#include "tuxonice.h"
+#include "tuxonice_storage.h"
+#include "tuxonice_alloc.h"
+
+static int toi_sysfs_initialised;
+
+static void toi_initialise_sysfs(void);
+
+static struct toi_sysfs_data sysfs_params[];
+
+#define to_sysfs_data(_attr) container_of(_attr, struct toi_sysfs_data, attr)
+
+static void toi_main_wrapper(void)
+{
+        toi_try_hibernate();
+}
+
+static ssize_t toi_attr_show(struct kobject *kobj, struct attribute *attr,
+                              char *page)
+{
+        struct toi_sysfs_data *sysfs_data = to_sysfs_data(attr);
+        int len = 0;
+        int full_prep = sysfs_data->flags & SYSFS_NEEDS_SM_FOR_READ;
+
+        if (full_prep && toi_start_anything(0))
+                return -EBUSY;
+
+        if (sysfs_data->flags & SYSFS_NEEDS_SM_FOR_READ)
+                toi_prepare_usm();
+
+        switch (sysfs_data->type) {
+        case TOI_SYSFS_DATA_CUSTOM:
+                len = (sysfs_data->data.special.read_sysfs) ?
+                        (sysfs_data->data.special.read_sysfs)(page, PAGE_SIZE)
+                        : 0;
+                break;
+        case TOI_SYSFS_DATA_BIT:
+                len = sprintf(page, "%d\n",
+                        -test_bit(sysfs_data->data.bit.bit,
+                                sysfs_data->data.bit.bit_vector));
+                break;
+        case TOI_SYSFS_DATA_INTEGER:
+                len = sprintf(page, "%d\n",
+                        *(sysfs_data->data.integer.variable));
+                break;
+        case TOI_SYSFS_DATA_LONG:
+                len = sprintf(page, "%ld\n",
+                        *(sysfs_data->data.a_long.variable));
+                break;
+        case TOI_SYSFS_DATA_UL:
+                len = sprintf(page, "%lu\n",
+                        *(sysfs_data->data.ul.variable));
+                break;
+        case TOI_SYSFS_DATA_STRING:
+                len = sprintf(page, "%s\n",
+                        sysfs_data->data.string.variable);
+                break;
+        }
+
+        if (sysfs_data->flags & SYSFS_NEEDS_SM_FOR_READ)
+                toi_cleanup_usm();
+
+        if (full_prep)
+                toi_finish_anything(0);
+
+        return len;
+}
+
+#define BOUND(_variable, _type) do { \
+        if (*_variable < sysfs_data->data._type.minimum) \
+                *_variable = sysfs_data->data._type.minimum; \
+        else if (*_variable > sysfs_data->data._type.maximum) \
+                *_variable = sysfs_data->data._type.maximum; \
+} while (0)
+
+static ssize_t toi_attr_store(struct kobject *kobj, struct attribute *attr,
+                const char *my_buf, size_t count)
+{
+        int assigned_temp_buffer = 0, result = count;
+        struct toi_sysfs_data *sysfs_data = to_sysfs_data(attr);
+
+        if (toi_start_anything((sysfs_data->flags & SYSFS_HIBERNATE_OR_RESUME)))
+                return -EBUSY;
+
+        ((char *) my_buf)[count] = 0;
+
+        if (sysfs_data->flags & SYSFS_NEEDS_SM_FOR_WRITE)
+                toi_prepare_usm();
+
+        switch (sysfs_data->type) {
+        case TOI_SYSFS_DATA_CUSTOM:
+                if (sysfs_data->data.special.write_sysfs)
+                        result = (sysfs_data->data.special.write_sysfs)(my_buf,
+                                        count);
+                break;
+        case TOI_SYSFS_DATA_BIT:
+                {
+                unsigned long value;
+                result = kstrtoul(my_buf, 0, &value);
+                if (result)
+                        break;
+                if (value)
+                        set_bit(sysfs_data->data.bit.bit,
+                                (sysfs_data->data.bit.bit_vector));
+                else
+                        clear_bit(sysfs_data->data.bit.bit,
+                                (sysfs_data->data.bit.bit_vector));
+                }
+                break;
+        case TOI_SYSFS_DATA_INTEGER:
+                {
+                        long temp;
+                        result = kstrtol(my_buf, 0, &temp);
+                        if (result)
+                                break;
+                        *(sysfs_data->data.integer.variable) = (int) temp;
+                        BOUND(sysfs_data->data.integer.variable, integer);
+                        break;
+                }
+        case TOI_SYSFS_DATA_LONG:
+                {
+                        long *variable =
+                                sysfs_data->data.a_long.variable;
+                        result = kstrtol(my_buf, 0, variable);
+                        if (result)
+                                break;
+                        BOUND(variable, a_long);
+                        break;
+                }
+        case TOI_SYSFS_DATA_UL:
+                {
+                        unsigned long *variable =
+                                sysfs_data->data.ul.variable;
+                        result = kstrtoul(my_buf, 0, variable);
+                        if (result)
+                                break;
+                        BOUND(variable, ul);
+                        break;
+                }
+                break;
+        case TOI_SYSFS_DATA_STRING:
+                {
+                        int copy_len = count;
+                        char *variable =
+                                sysfs_data->data.string.variable;
+
+                        if (sysfs_data->data.string.max_length &&
+                            (copy_len > sysfs_data->data.string.max_length))
+                                copy_len = sysfs_data->data.string.max_length;
+
+                        if (!variable) {
+                                variable = (char *) toi_get_zeroed_page(31,
+                                                TOI_ATOMIC_GFP);
+                                sysfs_data->data.string.variable = variable;
+                                assigned_temp_buffer = 1;
+                        }
+                        strncpy(variable, my_buf, copy_len);
+                        if (copy_len && my_buf[copy_len - 1] == '\n')
+                                variable[count - 1] = 0;
+                        variable[count] = 0;
+                }
+                break;
+        }
+
+        if (!result)
+                result = count;
+
+        /* Side effect routine? */
+        if (result == count && sysfs_data->write_side_effect)
+                sysfs_data->write_side_effect();
+
+        /* Free temporary buffers */
+        if (assigned_temp_buffer) {
+                toi_free_page(31,
+                        (unsigned long) sysfs_data->data.string.variable);
+                sysfs_data->data.string.variable = NULL;
+        }
+
+        if (sysfs_data->flags & SYSFS_NEEDS_SM_FOR_WRITE)
+                toi_cleanup_usm();
+
+        toi_finish_anything(sysfs_data->flags & SYSFS_HIBERNATE_OR_RESUME);
+
+        return result;
+}
+
+static struct sysfs_ops toi_sysfs_ops = {
+        .show        = &toi_attr_show,
+        .store        = &toi_attr_store,
+};
+
+static struct kobj_type toi_ktype = {
+        .sysfs_ops        = &toi_sysfs_ops,
+};
+
+struct kobject *tuxonice_kobj;
+
+/* Non-module sysfs entries.
+ *
+ * This array contains entries that are automatically registered at
+ * boot. Modules and the console code register their own entries separately.
+ */
+
+static struct toi_sysfs_data sysfs_params[] = {
+        SYSFS_CUSTOM("do_hibernate", SYSFS_WRITEONLY, NULL, NULL,
+                SYSFS_HIBERNATING, toi_main_wrapper),
+        SYSFS_CUSTOM("do_resume", SYSFS_WRITEONLY, NULL, NULL,
+                SYSFS_RESUMING, toi_try_resume)
+};
+
+void remove_toi_sysdir(struct kobject *kobj)
+{
+        if (!kobj)
+                return;
+
+        kobject_put(kobj);
+}
+
+struct kobject *make_toi_sysdir(char *name)
+{
+        struct kobject *kobj = kobject_create_and_add(name, tuxonice_kobj);
+
+        if (!kobj) {
+                printk(KERN_INFO "TuxOnIce: Can't allocate kobject for sysfs "
+                                "dir!\n");
+                return NULL;
+        }
+
+        kobj->ktype = &toi_ktype;
+
+        return kobj;
+}
+
+/* toi_register_sysfs_file
+ *
+ * Helper for registering a new /sysfs/tuxonice entry.
+ */
+
+int toi_register_sysfs_file(
+                struct kobject *kobj,
+                struct toi_sysfs_data *toi_sysfs_data)
+{
+        int result;
+
+        if (!toi_sysfs_initialised)
+                toi_initialise_sysfs();
+
+        result = sysfs_create_file(kobj, &toi_sysfs_data->attr);
+        if (result)
+                printk(KERN_INFO "TuxOnIce: sysfs_create_file for %s "
+                        "returned %d.\n",
+                        toi_sysfs_data->attr.name, result);
+        kobj->ktype = &toi_ktype;
+
+        return result;
+}
+
+/* toi_unregister_sysfs_file
+ *
+ * Helper for removing unwanted /sys/power/tuxonice entries.
+ *
+ */
+void toi_unregister_sysfs_file(struct kobject *kobj,
+                struct toi_sysfs_data *toi_sysfs_data)
+{
+        sysfs_remove_file(kobj, &toi_sysfs_data->attr);
+}
+
+void toi_cleanup_sysfs(void)
+{
+        int i,
+            numfiles = sizeof(sysfs_params) / sizeof(struct toi_sysfs_data);
+
+        if (!toi_sysfs_initialised)
+                return;
+
+        for (i = 0; i < numfiles; i++)
+                toi_unregister_sysfs_file(tuxonice_kobj, &sysfs_params[i]);
+
+        kobject_put(tuxonice_kobj);
+        toi_sysfs_initialised = 0;
+}
+
+/* toi_initialise_sysfs
+ *
+ * Initialise the /sysfs/tuxonice directory.
+ */
+
+static void toi_initialise_sysfs(void)
+{
+        int i;
+        int numfiles = sizeof(sysfs_params) / sizeof(struct toi_sysfs_data);
+
+        if (toi_sysfs_initialised)
+                return;
+
+        /* Make our TuxOnIce directory a child of /sys/power */
+        tuxonice_kobj = kobject_create_and_add("tuxonice", power_kobj);
+        if (!tuxonice_kobj)
+                return;
+
+        toi_sysfs_initialised = 1;
+
+        for (i = 0; i < numfiles; i++)
+                toi_register_sysfs_file(tuxonice_kobj, &sysfs_params[i]);
+}
+
+int toi_sysfs_init(void)
+{
+        toi_initialise_sysfs();
+        return 0;
+}
+
+void toi_sysfs_exit(void)
+{
+        toi_cleanup_sysfs();
+}
diff --git a/kernel/power/tuxonice_sysfs.h b/kernel/power/tuxonice_sysfs.h
new file mode 100644
index 000000000..1de954ce1
--- /dev/null
+++ b/kernel/power/tuxonice_sysfs.h
@@ -0,0 +1,137 @@
+/*
+ * kernel/power/tuxonice_sysfs.h
+ *
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/sysfs.h>
+
+struct toi_sysfs_data {
+        struct attribute attr;
+        int type;
+        int flags;
+        union {
+                struct {
+                        unsigned long *bit_vector;
+                        int bit;
+                } bit;
+                struct {
+                        int *variable;
+                        int minimum;
+                        int maximum;
+                } integer;
+                struct {
+                        long *variable;
+                        long minimum;
+                        long maximum;
+                } a_long;
+                struct {
+                        unsigned long *variable;
+                        unsigned long minimum;
+                        unsigned long maximum;
+                } ul;
+                struct {
+                        char *variable;
+                        int max_length;
+                } string;
+                struct {
+                        int (*read_sysfs) (const char *buffer, int count);
+                        int (*write_sysfs) (const char *buffer, int count);
+                        void *data;
+                } special;
+        } data;
+
+        /* Side effects routine. Used, eg, for reparsing the
+         * resume= entry when it changes */
+        void (*write_side_effect) (void);
+        struct list_head sysfs_data_list;
+};
+
+enum {
+        TOI_SYSFS_DATA_NONE = 1,
+        TOI_SYSFS_DATA_CUSTOM,
+        TOI_SYSFS_DATA_BIT,
+        TOI_SYSFS_DATA_INTEGER,
+        TOI_SYSFS_DATA_UL,
+        TOI_SYSFS_DATA_LONG,
+        TOI_SYSFS_DATA_STRING
+};
+
+#define SYSFS_WRITEONLY 0200
+#define SYSFS_READONLY 0444
+#define SYSFS_RW 0644
+
+#define SYSFS_BIT(_name, _mode, _ul, _bit, _flags) { \
+        .attr = {.name  = _name , .mode   = _mode }, \
+        .type = TOI_SYSFS_DATA_BIT, \
+        .flags = _flags, \
+        .data = { .bit = { .bit_vector = _ul, .bit = _bit } } }
+
+#define SYSFS_INT(_name, _mode, _int, _min, _max, _flags, _wse) { \
+        .attr = {.name  = _name , .mode   = _mode }, \
+        .type = TOI_SYSFS_DATA_INTEGER, \
+        .flags = _flags, \
+        .data = { .integer = { .variable = _int, .minimum = _min, \
+                        .maximum = _max } }, \
+        .write_side_effect = _wse }
+
+#define SYSFS_UL(_name, _mode, _ul, _min, _max, _flags) { \
+        .attr = {.name  = _name , .mode   = _mode }, \
+        .type = TOI_SYSFS_DATA_UL, \
+        .flags = _flags, \
+        .data = { .ul = { .variable = _ul, .minimum = _min, \
+                        .maximum = _max } } }
+
+#define SYSFS_LONG(_name, _mode, _long, _min, _max, _flags) { \
+        .attr = {.name  = _name , .mode   = _mode }, \
+        .type = TOI_SYSFS_DATA_LONG, \
+        .flags = _flags, \
+        .data = { .a_long = { .variable = _long, .minimum = _min, \
+                        .maximum = _max } } }
+
+#define SYSFS_STRING(_name, _mode, _string, _max_len, _flags, _wse) { \
+        .attr = {.name  = _name , .mode   = _mode }, \
+        .type = TOI_SYSFS_DATA_STRING, \
+        .flags = _flags, \
+        .data = { .string = { .variable = _string, .max_length = _max_len } }, \
+        .write_side_effect = _wse }
+
+#define SYSFS_CUSTOM(_name, _mode, _read, _write, _flags, _wse) { \
+        .attr = {.name  = _name , .mode   = _mode }, \
+        .type = TOI_SYSFS_DATA_CUSTOM, \
+        .flags = _flags, \
+        .data = { .special = { .read_sysfs = _read, .write_sysfs = _write } }, \
+        .write_side_effect = _wse }
+
+#define SYSFS_NONE(_name, _wse) { \
+        .attr = {.name  = _name , .mode   = SYSFS_WRITEONLY }, \
+        .type = TOI_SYSFS_DATA_NONE, \
+        .write_side_effect = _wse, \
+}
+
+/* Flags */
+#define SYSFS_NEEDS_SM_FOR_READ 1
+#define SYSFS_NEEDS_SM_FOR_WRITE 2
+#define SYSFS_HIBERNATE 4
+#define SYSFS_RESUME 8
+#define SYSFS_HIBERNATE_OR_RESUME (SYSFS_HIBERNATE | SYSFS_RESUME)
+#define SYSFS_HIBERNATING (SYSFS_HIBERNATE | SYSFS_NEEDS_SM_FOR_WRITE)
+#define SYSFS_RESUMING (SYSFS_RESUME | SYSFS_NEEDS_SM_FOR_WRITE)
+#define SYSFS_NEEDS_SM_FOR_BOTH \
+ (SYSFS_NEEDS_SM_FOR_READ | SYSFS_NEEDS_SM_FOR_WRITE)
+
+int toi_register_sysfs_file(struct kobject *kobj,
+                struct toi_sysfs_data *toi_sysfs_data);
+void toi_unregister_sysfs_file(struct kobject *kobj,
+                struct toi_sysfs_data *toi_sysfs_data);
+
+extern struct kobject *tuxonice_kobj;
+
+struct kobject *make_toi_sysdir(char *name);
+void remove_toi_sysdir(struct kobject *obj);
+extern void toi_cleanup_sysfs(void);
+
+extern int toi_sysfs_init(void);
+extern void toi_sysfs_exit(void);
diff --git a/kernel/power/tuxonice_ui.c b/kernel/power/tuxonice_ui.c
new file mode 100644
index 000000000..76152f3ff
--- /dev/null
+++ b/kernel/power/tuxonice_ui.c
@@ -0,0 +1,247 @@
+/*
+ * kernel/power/tuxonice_ui.c
+ *
+ * Copyright (C) 1998-2001 Gabor Kuti <seasons@fornax.hu>
+ * Copyright (C) 1998,2001,2002 Pavel Machek <pavel@suse.cz>
+ * Copyright (C) 2002-2003 Florent Chabaud <fchabaud@free.fr>
+ * Copyright (C) 2002-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * Routines for TuxOnIce's user interface.
+ *
+ * The user interface code talks to a userspace program via a
+ * netlink socket.
+ *
+ * The kernel side:
+ * - starts the userui program;
+ * - sends text messages and progress bar status;
+ *
+ * The user space side:
+ * - passes messages regarding user requests (abort, toggle reboot etc)
+ *
+ */
+
+#define __KERNEL_SYSCALLS__
+
+#include <linux/reboot.h>
+
+#include "tuxonice_sysfs.h"
+#include "tuxonice_modules.h"
+#include "tuxonice.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_netlink.h"
+#include "tuxonice_power_off.h"
+#include "tuxonice_builtin.h"
+
+static char local_printf_buf[1024];        /* Same as printk - should be safe */
+struct ui_ops *toi_current_ui;
+
+/**
+ * toi_wait_for_keypress - Wait for keypress via userui or /dev/console.
+ *
+ * @timeout: Maximum time to wait.
+ *
+ * Wait for a keypress, either from userui or /dev/console if userui isn't
+ * available. The non-userui path is particularly for at boot-time, prior
+ * to userui being started, when we have an important warning to give to
+ * the user.
+ */
+static char toi_wait_for_keypress(int timeout)
+{
+        if (toi_current_ui && toi_current_ui->wait_for_key(timeout))
+                return ' ';
+
+        return toi_wait_for_keypress_dev_console(timeout);
+}
+
+/* toi_early_boot_message()
+ * Description:        Handle errors early in the process of booting.
+ *                 The user may press C to continue booting, perhaps
+ *                 invalidating the image,  or space to reboot.
+ *                 This works from either the serial console or normally
+ *                 attached keyboard.
+ *
+ *                 Note that we come in here from init, while the kernel is
+ *                 locked. If we want to get events from the serial console,
+ *                 we need to temporarily unlock the kernel.
+ *
+ *                 toi_early_boot_message may also be called post-boot.
+ *                 In this case, it simply printks the message and returns.
+ *
+ * Arguments:        int        Whether we are able to erase the image.
+ *                 int        default_answer. What to do when we timeout. This
+ *                         will normally be continue, but the user might
+ *                         provide command line options (__setup) to override
+ *                         particular cases.
+ *                 Char *. Pointer to a string explaining why we're moaning.
+ */
+
+#define say(message, a...) printk(KERN_EMERG message, ##a)
+
+void toi_early_boot_message(int message_detail, int default_answer,
+        char *warning_reason, ...)
+{
+#if defined(CONFIG_VT) || defined(CONFIG_SERIAL_CONSOLE)
+        unsigned long orig_state = get_toi_state(), continue_req = 0;
+        unsigned long orig_loglevel = console_loglevel;
+        int can_ask = 1;
+#else
+        int can_ask = 0;
+#endif
+
+        va_list args;
+        int printed_len;
+
+        if (!toi_wait) {
+                set_toi_state(TOI_CONTINUE_REQ);
+                can_ask = 0;
+        }
+
+        if (warning_reason) {
+                va_start(args, warning_reason);
+                printed_len = vsnprintf(local_printf_buf,
+                                sizeof(local_printf_buf),
+                                warning_reason,
+                                args);
+                va_end(args);
+        }
+
+        if (!test_toi_state(TOI_BOOT_TIME)) {
+                printk("TuxOnIce: %s\n", local_printf_buf);
+                return;
+        }
+
+        if (!can_ask) {
+                continue_req = !!default_answer;
+                goto post_ask;
+        }
+
+#if defined(CONFIG_VT) || defined(CONFIG_SERIAL_CONSOLE)
+        console_loglevel = 7;
+
+        say("=== TuxOnIce ===\n\n");
+        if (warning_reason) {
+                say("BIG FAT WARNING!! %s\n\n", local_printf_buf);
+                switch (message_detail) {
+                case 0:
+                        say("If you continue booting, note that any image WILL"
+                                "NOT BE REMOVED.\nTuxOnIce is unable to do so "
+                                "because the appropriate modules aren't\n"
+                                "loaded. You should manually remove the image "
+                                "to avoid any\npossibility of corrupting your "
+                                "filesystem(s) later.\n");
+                        break;
+                case 1:
+                        say("If you want to use the current TuxOnIce image, "
+                                "reboot and try\nagain with the same kernel "
+                                "that you hibernated from. If you want\n"
+                                "to forget that image, continue and the image "
+                                "will be erased.\n");
+                        break;
+                }
+                say("Press SPACE to reboot or C to continue booting with "
+                        "this kernel\n\n");
+                if (toi_wait > 0)
+                        say("Default action if you don't select one in %d "
+                                "seconds is: %s.\n",
+                                toi_wait,
+                                default_answer == TOI_CONTINUE_REQ ?
+                                "continue booting" : "reboot");
+        } else {
+                say("BIG FAT WARNING!!\n\n"
+                        "You have tried to resume from this image before.\n"
+                        "If it failed once, it may well fail again.\n"
+                        "Would you like to remove the image and boot "
+                        "normally?\nThis will be equivalent to entering "
+                        "noresume on the\nkernel command line.\n\n"
+                        "Press SPACE to remove the image or C to continue "
+                        "resuming.\n\n");
+                if (toi_wait > 0)
+                        say("Default action if you don't select one in %d "
+                                "seconds is: %s.\n", toi_wait,
+                                !!default_answer ?
+                                "continue resuming" : "remove the image");
+        }
+        console_loglevel = orig_loglevel;
+
+        set_toi_state(TOI_SANITY_CHECK_PROMPT);
+        clear_toi_state(TOI_CONTINUE_REQ);
+
+        if (toi_wait_for_keypress(toi_wait) == 0) /* We timed out */
+                continue_req = !!default_answer;
+        else
+                continue_req = test_toi_state(TOI_CONTINUE_REQ);
+
+#endif /* CONFIG_VT or CONFIG_SERIAL_CONSOLE */
+
+post_ask:
+        if ((warning_reason) && (!continue_req))
+                kernel_restart(NULL);
+
+        restore_toi_state(orig_state);
+        if (continue_req)
+                set_toi_state(TOI_CONTINUE_REQ);
+}
+
+#undef say
+
+/*
+ * User interface specific /sys/power/tuxonice entries.
+ */
+
+static struct toi_sysfs_data sysfs_params[] = {
+#if defined(CONFIG_NET) && defined(CONFIG_SYSFS)
+        SYSFS_INT("default_console_level", SYSFS_RW,
+                        &toi_bkd.toi_default_console_level, 0, 7, 0, NULL),
+        SYSFS_UL("debug_sections", SYSFS_RW, &toi_bkd.toi_debug_state, 0,
+                        1 << 30, 0),
+        SYSFS_BIT("log_everything", SYSFS_RW, &toi_bkd.toi_action, TOI_LOGALL,
+                        0)
+#endif
+};
+
+static struct toi_module_ops userui_ops = {
+        .type                                = MISC_HIDDEN_MODULE,
+        .name                                = "printk ui",
+        .directory                        = "user_interface",
+        .module                                = THIS_MODULE,
+        .sysfs_data                        = sysfs_params,
+        .num_sysfs_entries                = sizeof(sysfs_params) /
+                sizeof(struct toi_sysfs_data),
+};
+
+int toi_register_ui_ops(struct ui_ops *this_ui)
+{
+        if (toi_current_ui) {
+                printk(KERN_INFO "Only one TuxOnIce user interface module can "
+                                "be loaded at a time.");
+                return -EBUSY;
+        }
+
+        toi_current_ui = this_ui;
+
+        return 0;
+}
+
+void toi_remove_ui_ops(struct ui_ops *this_ui)
+{
+        if (toi_current_ui != this_ui)
+                return;
+
+        toi_current_ui = NULL;
+}
+
+/* toi_console_sysfs_init
+ * Description: Boot time initialisation for user interface.
+ */
+
+int toi_ui_init(void)
+{
+        return toi_register_module(&userui_ops);
+}
+
+void toi_ui_exit(void)
+{
+        toi_unregister_module(&userui_ops);
+}
diff --git a/kernel/power/tuxonice_ui.h b/kernel/power/tuxonice_ui.h
new file mode 100644
index 000000000..4934e3a91
--- /dev/null
+++ b/kernel/power/tuxonice_ui.h
@@ -0,0 +1,97 @@
+/*
+ * kernel/power/tuxonice_ui.h
+ *
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ */
+
+enum {
+        DONT_CLEAR_BAR,
+        CLEAR_BAR
+};
+
+enum {
+        /* Userspace -> Kernel */
+        USERUI_MSG_ABORT = 0x11,
+        USERUI_MSG_SET_STATE = 0x12,
+        USERUI_MSG_GET_STATE = 0x13,
+        USERUI_MSG_GET_DEBUG_STATE = 0x14,
+        USERUI_MSG_SET_DEBUG_STATE = 0x15,
+        USERUI_MSG_SPACE = 0x18,
+        USERUI_MSG_GET_POWERDOWN_METHOD = 0x1A,
+        USERUI_MSG_SET_POWERDOWN_METHOD = 0x1B,
+        USERUI_MSG_GET_LOGLEVEL = 0x1C,
+        USERUI_MSG_SET_LOGLEVEL = 0x1D,
+        USERUI_MSG_PRINTK = 0x1E,
+
+        /* Kernel -> Userspace */
+        USERUI_MSG_MESSAGE = 0x21,
+        USERUI_MSG_PROGRESS = 0x22,
+        USERUI_MSG_POST_ATOMIC_RESTORE = 0x25,
+
+        USERUI_MSG_MAX,
+};
+
+struct userui_msg_params {
+        u32 a, b, c, d;
+        char text[255];
+};
+
+struct ui_ops {
+        char (*wait_for_key) (int timeout);
+        u32 (*update_status) (u32 value, u32 maximum, const char *fmt, ...);
+        void (*prepare_status) (int clearbar, const char *fmt, ...);
+        void (*cond_pause) (int pause, char *message);
+        void (*abort)(int result_code, const char *fmt, ...);
+        void (*prepare)(void);
+        void (*cleanup)(void);
+        void (*message)(u32 section, u32 level, u32 normally_logged,
+                        const char *fmt, ...);
+};
+
+extern struct ui_ops *toi_current_ui;
+
+#define toi_update_status(val, max, fmt, args...) \
+ (toi_current_ui ? (toi_current_ui->update_status) (val, max, fmt, ##args) : \
+        max)
+
+#define toi_prepare_console(void) \
+        do { if (toi_current_ui) \
+                (toi_current_ui->prepare)(); \
+        } while (0)
+
+#define toi_cleanup_console(void) \
+        do { if (toi_current_ui) \
+                (toi_current_ui->cleanup)(); \
+        } while (0)
+
+#define abort_hibernate(result, fmt, args...) \
+        do { if (toi_current_ui) \
+                (toi_current_ui->abort)(result, fmt, ##args); \
+             else { \
+                set_abort_result(result); \
+             } \
+        } while (0)
+
+#define toi_cond_pause(pause, message) \
+        do { if (toi_current_ui) \
+                (toi_current_ui->cond_pause)(pause, message); \
+        } while (0)
+
+#define toi_prepare_status(clear, fmt, args...) \
+        do { if (toi_current_ui) \
+                (toi_current_ui->prepare_status)(clear, fmt, ##args); \
+             else \
+                printk(KERN_INFO fmt "%s", ##args, "\n"); \
+        } while (0)
+
+#define toi_message(sn, lev, log, fmt, a...) \
+do { \
+        if (toi_current_ui && (!sn || test_debug_state(sn))) \
+                toi_current_ui->message(sn, lev, log, fmt, ##a); \
+} while (0)
+
+__exit void toi_ui_cleanup(void);
+extern int toi_ui_init(void);
+extern void toi_ui_exit(void);
+extern int toi_register_ui_ops(struct ui_ops *this_ui);
+extern void toi_remove_ui_ops(struct ui_ops *this_ui);
diff --git a/kernel/power/tuxonice_userui.c b/kernel/power/tuxonice_userui.c
new file mode 100644
index 000000000..6aa5ac3eb
--- /dev/null
+++ b/kernel/power/tuxonice_userui.c
@@ -0,0 +1,658 @@
+/*
+ * kernel/power/user_ui.c
+ *
+ * Copyright (C) 2005-2007 Bernard Blackham
+ * Copyright (C) 2002-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * This file is released under the GPLv2.
+ *
+ * Routines for TuxOnIce's user interface.
+ *
+ * The user interface code talks to a userspace program via a
+ * netlink socket.
+ *
+ * The kernel side:
+ * - starts the userui program;
+ * - sends text messages and progress bar status;
+ *
+ * The user space side:
+ * - passes messages regarding user requests (abort, toggle reboot etc)
+ *
+ */
+
+#define __KERNEL_SYSCALLS__
+
+#include <linux/suspend.h>
+#include <linux/freezer.h>
+#include <linux/console.h>
+#include <linux/ctype.h>
+#include <linux/tty.h>
+#include <linux/vt_kern.h>
+#include <linux/reboot.h>
+#include <linux/security.h>
+#include <linux/syscalls.h>
+#include <linux/vt.h>
+
+#include "tuxonice_sysfs.h"
+#include "tuxonice_modules.h"
+#include "tuxonice.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_netlink.h"
+#include "tuxonice_power_off.h"
+
+static char local_printf_buf[1024];        /* Same as printk - should be safe */
+
+static struct user_helper_data ui_helper_data;
+static struct toi_module_ops userui_ops;
+static int orig_kmsg;
+
+static char lastheader[512];
+static int lastheader_message_len;
+static int ui_helper_changed; /* Used at resume-time so don't overwrite value
+                                set from initrd/ramfs. */
+
+/* Number of distinct progress amounts that userspace can display */
+static int progress_granularity = 30;
+
+static DECLARE_WAIT_QUEUE_HEAD(userui_wait_for_key);
+static int userui_wait_should_wake;
+
+#define toi_stop_waiting_for_userui_key() \
+{ \
+        userui_wait_should_wake = true; \
+        wake_up_interruptible(&userui_wait_for_key); \
+}
+
+/**
+ * ui_nl_set_state - Update toi_action based on a message from userui.
+ *
+ * @n: The bit (1 << bit) to set.
+ */
+static void ui_nl_set_state(int n)
+{
+        /* Only let them change certain settings */
+        static const u32 toi_action_mask =
+                (1 << TOI_REBOOT) | (1 << TOI_PAUSE) |
+                (1 << TOI_LOGALL) |
+                (1 << TOI_SINGLESTEP) |
+                (1 << TOI_PAUSE_NEAR_PAGESET_END);
+        static unsigned long new_action;
+
+        new_action = (toi_bkd.toi_action & (~toi_action_mask)) |
+                (n & toi_action_mask);
+
+        printk(KERN_DEBUG "n is %x. Action flags being changed from %lx "
+                        "to %lx.", n, toi_bkd.toi_action, new_action);
+        toi_bkd.toi_action = new_action;
+
+        if (!test_action_state(TOI_PAUSE) &&
+                        !test_action_state(TOI_SINGLESTEP))
+                toi_stop_waiting_for_userui_key();
+}
+
+/**
+ * userui_post_atomic_restore - Tell userui that atomic restore just happened.
+ *
+ * Tell userui that atomic restore just occured, so that it can do things like
+ * redrawing the screen, re-getting settings and so on.
+ */
+static void userui_post_atomic_restore(struct toi_boot_kernel_data *bkd)
+{
+        toi_send_netlink_message(&ui_helper_data,
+                        USERUI_MSG_POST_ATOMIC_RESTORE, NULL, 0);
+}
+
+/**
+ * userui_storage_needed - Report how much memory in image header is needed.
+ */
+static int userui_storage_needed(void)
+{
+        return sizeof(ui_helper_data.program) + 1 + sizeof(int);
+}
+
+/**
+ * userui_save_config_info - Fill buffer with config info for image header.
+ *
+ * @buf: Buffer into which to put the config info we want to save.
+ */
+static int userui_save_config_info(char *buf)
+{
+        *((int *) buf) = progress_granularity;
+        memcpy(buf + sizeof(int), ui_helper_data.program,
+                        sizeof(ui_helper_data.program));
+        return sizeof(ui_helper_data.program) + sizeof(int) + 1;
+}
+
+/**
+ * userui_load_config_info - Restore config info from buffer.
+ *
+ * @buf: Buffer containing header info loaded.
+ * @size: Size of data loaded for this module.
+ */
+static void userui_load_config_info(char *buf, int size)
+{
+        progress_granularity = *((int *) buf);
+        size -= sizeof(int);
+
+        /* Don't load the saved path if one has already been set */
+        if (ui_helper_changed)
+                return;
+
+        if (size > sizeof(ui_helper_data.program))
+                size = sizeof(ui_helper_data.program);
+
+        memcpy(ui_helper_data.program, buf + sizeof(int), size);
+        ui_helper_data.program[sizeof(ui_helper_data.program)-1] = '\0';
+}
+
+/**
+ * set_ui_program_set: Record that userui program was changed.
+ *
+ * Side effect routine for when the userui program is set. In an initrd or
+ * ramfs, the user may set a location for the userui program. If this happens,
+ * we don't want to reload the value that was saved in the image header. This
+ * routine allows us to flag that we shouldn't restore the program name from
+ * the image header.
+ */
+static void set_ui_program_set(void)
+{
+        ui_helper_changed = 1;
+}
+
+/**
+ * userui_memory_needed - Tell core how much memory to reserve for us.
+ */
+static int userui_memory_needed(void)
+{
+        /* ball park figure of 128 pages */
+        return 128 * PAGE_SIZE;
+}
+
+/**
+ * userui_update_status - Update the progress bar and (if on) in-bar message.
+ *
+ * @value: Current progress percentage numerator.
+ * @maximum: Current progress percentage denominator.
+ * @fmt: Message to be displayed in the middle of the progress bar.
+ *
+ * Note that a NULL message does not mean that any previous message is erased!
+ * For that, you need toi_prepare_status with clearbar on.
+ *
+ * Returns an unsigned long, being the next numerator (as determined by the
+ * maximum and progress granularity) where status needs to be updated.
+ * This is to reduce unnecessary calls to update_status.
+ */
+static u32 userui_update_status(u32 value, u32 maximum, const char *fmt, ...)
+{
+        static u32 last_step = 9999;
+        struct userui_msg_params msg;
+        u32 this_step, next_update;
+        int bitshift;
+
+        if (ui_helper_data.pid == -1)
+                return 0;
+
+        if ((!maximum) || (!progress_granularity))
+                return maximum;
+
+        if (value < 0)
+                value = 0;
+
+        if (value > maximum)
+                value = maximum;
+
+        /* Try to avoid math problems - we can't do 64 bit math here
+         * (and shouldn't need it - anyone got screen resolution
+         * of 65536 pixels or more?) */
+        bitshift = fls(maximum) - 16;
+        if (bitshift > 0) {
+                u32 temp_maximum = maximum >> bitshift;
+                u32 temp_value = value >> bitshift;
+                this_step = (u32)
+                        (temp_value * progress_granularity / temp_maximum);
+                next_update = (((this_step + 1) * temp_maximum /
+                                        progress_granularity) + 1) << bitshift;
+        } else {
+                this_step = (u32) (value * progress_granularity / maximum);
+                next_update = ((this_step + 1) * maximum /
+                                progress_granularity) + 1;
+        }
+
+        if (this_step == last_step)
+                return next_update;
+
+        memset(&msg, 0, sizeof(msg));
+
+        msg.a = this_step;
+        msg.b = progress_granularity;
+
+        if (fmt) {
+                va_list args;
+                va_start(args, fmt);
+                vsnprintf(msg.text, sizeof(msg.text), fmt, args);
+                va_end(args);
+                msg.text[sizeof(msg.text)-1] = '\0';
+        }
+
+        toi_send_netlink_message(&ui_helper_data, USERUI_MSG_PROGRESS,
+                        &msg, sizeof(msg));
+        last_step = this_step;
+
+        return next_update;
+}
+
+/**
+ * userui_message - Display a message without necessarily logging it.
+ *
+ * @section: Type of message. Messages can be filtered by type.
+ * @level: Degree of importance of the message. Lower values = higher priority.
+ * @normally_logged: Whether logged even if log_everything is off.
+ * @fmt: Message (and parameters).
+ *
+ * This function is intended to do the same job as printk, but without normally
+ * logging what is printed. The point is to be able to get debugging info on
+ * screen without filling the logs with "1/534. ^M 2/534^M. 3/534^M"
+ *
+ * It may be called from an interrupt context - can't sleep!
+ */
+static void userui_message(u32 section, u32 level, u32 normally_logged,
+                const char *fmt, ...)
+{
+        struct userui_msg_params msg;
+
+        if ((level) && (level > console_loglevel))
+                return;
+
+        memset(&msg, 0, sizeof(msg));
+
+        msg.a = section;
+        msg.b = level;
+        msg.c = normally_logged;
+
+        if (fmt) {
+                va_list args;
+                va_start(args, fmt);
+                vsnprintf(msg.text, sizeof(msg.text), fmt, args);
+                va_end(args);
+                msg.text[sizeof(msg.text)-1] = '\0';
+        }
+
+        if (test_action_state(TOI_LOGALL))
+                printk(KERN_INFO "%s\n", msg.text);
+
+        toi_send_netlink_message(&ui_helper_data, USERUI_MSG_MESSAGE,
+                        &msg, sizeof(msg));
+}
+
+/**
+ * wait_for_key_via_userui - Wait for userui to receive a keypress.
+ */
+static void wait_for_key_via_userui(void)
+{
+        DECLARE_WAITQUEUE(wait, current);
+
+        add_wait_queue(&userui_wait_for_key, &wait);
+        set_current_state(TASK_INTERRUPTIBLE);
+
+        wait_event_interruptible(userui_wait_for_key, userui_wait_should_wake);
+        userui_wait_should_wake = false;
+
+        set_current_state(TASK_RUNNING);
+        remove_wait_queue(&userui_wait_for_key, &wait);
+}
+
+/**
+ * userui_prepare_status - Display high level messages.
+ *
+ * @clearbar: Whether to clear the progress bar.
+ * @fmt...: New message for the title.
+ *
+ * Prepare the 'nice display', drawing the header and version, along with the
+ * current action and perhaps also resetting the progress bar.
+ */
+static void userui_prepare_status(int clearbar, const char *fmt, ...)
+{
+        va_list args;
+
+        if (fmt) {
+                va_start(args, fmt);
+                lastheader_message_len = vsnprintf(lastheader, 512, fmt, args);
+                va_end(args);
+        }
+
+        if (clearbar)
+                toi_update_status(0, 1, NULL);
+
+        if (ui_helper_data.pid == -1)
+                printk(KERN_EMERG "%s\n", lastheader);
+        else
+                toi_message(0, TOI_STATUS, 1, lastheader, NULL);
+}
+
+/**
+ * toi_wait_for_keypress - Wait for keypress via userui.
+ *
+ * @timeout: Maximum time to wait.
+ *
+ * Wait for a keypress from userui.
+ *
+ * FIXME: Implement timeout?
+ */
+static char userui_wait_for_keypress(int timeout)
+{
+        char key = '\0';
+
+        if (ui_helper_data.pid != -1) {
+                wait_for_key_via_userui();
+                key = ' ';
+        }
+
+        return key;
+}
+
+/**
+ * userui_abort_hibernate - Abort a cycle & tell user if they didn't request it.
+ *
+ * @result_code: Reason why we're aborting (1 << bit).
+ * @fmt: Message to display if telling the user what's going on.
+ *
+ * Abort a cycle. If this wasn't at the user's request (and we're displaying
+ * output), tell the user why and wait for them to acknowledge the message.
+ */
+static void userui_abort_hibernate(int result_code, const char *fmt, ...)
+{
+        va_list args;
+        int printed_len = 0;
+
+        set_result_state(result_code);
+
+        if (test_result_state(TOI_ABORTED))
+                return;
+
+        set_result_state(TOI_ABORTED);
+
+        if (test_result_state(TOI_ABORT_REQUESTED))
+                return;
+
+        va_start(args, fmt);
+        printed_len = vsnprintf(local_printf_buf,  sizeof(local_printf_buf),
+                        fmt, args);
+        va_end(args);
+        if (ui_helper_data.pid != -1)
+                printed_len = sprintf(local_printf_buf + printed_len,
+                                        " (Press SPACE to continue)");
+
+        toi_prepare_status(CLEAR_BAR, "%s", local_printf_buf);
+
+        if (ui_helper_data.pid != -1)
+                userui_wait_for_keypress(0);
+}
+
+/**
+ * request_abort_hibernate - Abort hibernating or resuming at user request.
+ *
+ * Handle the user requesting the cancellation of a hibernation or resume by
+ * pressing escape.
+ */
+static void request_abort_hibernate(void)
+{
+        if (test_result_state(TOI_ABORT_REQUESTED) ||
+           !test_action_state(TOI_CAN_CANCEL))
+                return;
+
+        if (test_toi_state(TOI_NOW_RESUMING)) {
+                toi_prepare_status(CLEAR_BAR, "Escape pressed. "
+                                        "Powering down again.");
+                set_toi_state(TOI_STOP_RESUME);
+                while (!test_toi_state(TOI_IO_STOPPED))
+                        schedule();
+                if (toiActiveAllocator->mark_resume_attempted)
+                        toiActiveAllocator->mark_resume_attempted(0);
+                toi_power_down();
+        }
+
+        toi_prepare_status(CLEAR_BAR, "--- ESCAPE PRESSED :"
+                                        " ABORTING HIBERNATION ---");
+        set_abort_result(TOI_ABORT_REQUESTED);
+        toi_stop_waiting_for_userui_key();
+}
+
+/**
+ * userui_user_rcv_msg - Receive a netlink message from userui.
+ *
+ * @skb: skb received.
+ * @nlh: Netlink header received.
+ */
+static int userui_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+{
+        int type;
+        int *data;
+
+        type = nlh->nlmsg_type;
+
+        /* A control message: ignore them */
+        if (type < NETLINK_MSG_BASE)
+                return 0;
+
+        /* Unknown message: reply with EINVAL */
+        if (type >= USERUI_MSG_MAX)
+                return -EINVAL;
+
+        /* All operations require privileges, even GET */
+        if (!capable(CAP_NET_ADMIN))
+                return -EPERM;
+
+        /* Only allow one task to receive NOFREEZE privileges */
+        if (type == NETLINK_MSG_NOFREEZE_ME && ui_helper_data.pid != -1) {
+                printk(KERN_INFO "Got NOFREEZE_ME request when "
+                        "ui_helper_data.pid is %d.\n", ui_helper_data.pid);
+                return -EBUSY;
+        }
+
+        data = (int *) NLMSG_DATA(nlh);
+
+        switch (type) {
+        case USERUI_MSG_ABORT:
+                request_abort_hibernate();
+                return 0;
+        case USERUI_MSG_GET_STATE:
+                toi_send_netlink_message(&ui_helper_data,
+                                USERUI_MSG_GET_STATE, &toi_bkd.toi_action,
+                                sizeof(toi_bkd.toi_action));
+                return 0;
+        case USERUI_MSG_GET_DEBUG_STATE:
+                toi_send_netlink_message(&ui_helper_data,
+                                USERUI_MSG_GET_DEBUG_STATE,
+                                &toi_bkd.toi_debug_state,
+                                sizeof(toi_bkd.toi_debug_state));
+                return 0;
+        case USERUI_MSG_SET_STATE:
+                if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(int)))
+                        return -EINVAL;
+                ui_nl_set_state(*data);
+                return 0;
+        case USERUI_MSG_SET_DEBUG_STATE:
+                if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(int)))
+                        return -EINVAL;
+                toi_bkd.toi_debug_state = (*data);
+                return 0;
+        case USERUI_MSG_SPACE:
+                toi_stop_waiting_for_userui_key();
+                return 0;
+        case USERUI_MSG_GET_POWERDOWN_METHOD:
+                toi_send_netlink_message(&ui_helper_data,
+                                USERUI_MSG_GET_POWERDOWN_METHOD,
+                                &toi_poweroff_method,
+                                sizeof(toi_poweroff_method));
+                return 0;
+        case USERUI_MSG_SET_POWERDOWN_METHOD:
+                if (nlh->nlmsg_len != NLMSG_LENGTH(sizeof(char)))
+                        return -EINVAL;
+                toi_poweroff_method = (unsigned long)(*data);
+                return 0;
+        case USERUI_MSG_GET_LOGLEVEL:
+                toi_send_netlink_message(&ui_helper_data,
+                                USERUI_MSG_GET_LOGLEVEL,
+                                &toi_bkd.toi_default_console_level,
+                                sizeof(toi_bkd.toi_default_console_level));
+                return 0;
+        case USERUI_MSG_SET_LOGLEVEL:
+                if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(int)))
+                        return -EINVAL;
+                toi_bkd.toi_default_console_level = (*data);
+                return 0;
+        case USERUI_MSG_PRINTK:
+                printk(KERN_INFO "%s", (char *) data);
+                return 0;
+        }
+
+        /* Unhandled here */
+        return 1;
+}
+
+/**
+ * userui_cond_pause - Possibly pause at user request.
+ *
+ * @pause: Whether to pause or just display the message.
+ * @message: Message to display at the start of pausing.
+ *
+ * Potentially pause and wait for the user to tell us to continue. We normally
+ * only pause when @pause is set. While paused, the user can do things like
+ * changing the loglevel, toggling the display of debugging sections and such
+ * like.
+ */
+static void userui_cond_pause(int pause, char *message)
+{
+        int displayed_message = 0, last_key = 0;
+
+        while (last_key != 32 &&
+                ui_helper_data.pid != -1 &&
+                ((test_action_state(TOI_PAUSE) && pause) ||
+                 (test_action_state(TOI_SINGLESTEP)))) {
+                if (!displayed_message) {
+                        toi_prepare_status(DONT_CLEAR_BAR,
+                           "%s Press SPACE to continue.%s",
+                           message ? message : "",
+                           (test_action_state(TOI_SINGLESTEP)) ?
+                           " Single step on." : "");
+                        displayed_message = 1;
+                }
+                last_key = userui_wait_for_keypress(0);
+        }
+        schedule();
+}
+
+/**
+ * userui_prepare_console - Prepare the console for use.
+ *
+ * Prepare a console for use, saving current kmsg settings and attempting to
+ * start userui. Console loglevel changes are handled by userui.
+ */
+static void userui_prepare_console(void)
+{
+        orig_kmsg = vt_kmsg_redirect(fg_console + 1);
+
+        ui_helper_data.pid = -1;
+
+        if (!userui_ops.enabled) {
+                printk(KERN_INFO "TuxOnIce: Userui disabled.\n");
+                return;
+        }
+
+        if (*ui_helper_data.program)
+                toi_netlink_setup(&ui_helper_data);
+        else
+                printk(KERN_INFO "TuxOnIce: Userui program not configured.\n");
+}
+
+/**
+ * userui_cleanup_console - Cleanup after a cycle.
+ *
+ * Tell userui to cleanup, and restore kmsg_redirect to its original value.
+ */
+
+static void userui_cleanup_console(void)
+{
+        if (ui_helper_data.pid > -1)
+                toi_netlink_close(&ui_helper_data);
+
+        vt_kmsg_redirect(orig_kmsg);
+}
+
+/*
+ * User interface specific /sys/power/tuxonice entries.
+ */
+
+static struct toi_sysfs_data sysfs_params[] = {
+#if defined(CONFIG_NET) && defined(CONFIG_SYSFS)
+        SYSFS_BIT("enable_escape", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_CAN_CANCEL, 0),
+        SYSFS_BIT("pause_between_steps", SYSFS_RW, &toi_bkd.toi_action,
+                        TOI_PAUSE, 0),
+        SYSFS_INT("enabled", SYSFS_RW, &userui_ops.enabled, 0, 1, 0, NULL),
+        SYSFS_INT("progress_granularity", SYSFS_RW, &progress_granularity, 1,
+                        2048, 0, NULL),
+        SYSFS_STRING("program", SYSFS_RW, ui_helper_data.program, 255, 0,
+                        set_ui_program_set),
+        SYSFS_INT("debug", SYSFS_RW, &ui_helper_data.debug, 0, 1, 0, NULL)
+#endif
+};
+
+static struct toi_module_ops userui_ops = {
+        .type                                = MISC_MODULE,
+        .name                                = "userui",
+        .shared_directory                = "user_interface",
+        .module                                = THIS_MODULE,
+        .storage_needed                        = userui_storage_needed,
+        .save_config_info                = userui_save_config_info,
+        .load_config_info                = userui_load_config_info,
+        .memory_needed                        = userui_memory_needed,
+        .post_atomic_restore                = userui_post_atomic_restore,
+        .sysfs_data                        = sysfs_params,
+        .num_sysfs_entries                = sizeof(sysfs_params) /
+                sizeof(struct toi_sysfs_data),
+};
+
+static struct ui_ops my_ui_ops = {
+        .update_status                        = userui_update_status,
+        .message                        = userui_message,
+        .prepare_status                        = userui_prepare_status,
+        .abort                                = userui_abort_hibernate,
+        .cond_pause                        = userui_cond_pause,
+        .prepare                        = userui_prepare_console,
+        .cleanup                        = userui_cleanup_console,
+        .wait_for_key                        = userui_wait_for_keypress,
+};
+
+/**
+ * toi_user_ui_init - Boot time initialisation for user interface.
+ *
+ * Invoked from the core init routine.
+ */
+static __init int toi_user_ui_init(void)
+{
+        int result;
+
+        ui_helper_data.nl = NULL;
+        strncpy(ui_helper_data.program, CONFIG_TOI_USERUI_DEFAULT_PATH, 255);
+        ui_helper_data.pid = -1;
+        ui_helper_data.skb_size = sizeof(struct userui_msg_params);
+        ui_helper_data.pool_limit = 6;
+        ui_helper_data.netlink_id = NETLINK_TOI_USERUI;
+        ui_helper_data.name = "userspace ui";
+        ui_helper_data.rcv_msg = userui_user_rcv_msg;
+        ui_helper_data.interface_version = 8;
+        ui_helper_data.must_init = 0;
+        ui_helper_data.not_ready = userui_cleanup_console;
+        init_completion(&ui_helper_data.wait_for_process);
+        result = toi_register_module(&userui_ops);
+        if (!result) {
+          result = toi_register_ui_ops(&my_ui_ops);
+          if (result)
+            toi_unregister_module(&userui_ops);
+        }
+
+        return result;
+}
+
+late_initcall(toi_user_ui_init);
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index af4e6968c..464c10ac4 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -33,6 +33,7 @@
 #include <linux/bootmem.h>
 #include <linux/memblock.h>
 #include <linux/syscalls.h>
+#include <linux/suspend.h>
 #include <linux/kexec.h>
 #include <linux/kdb.h>
 #include <linux/ratelimit.h>
@@ -284,6 +285,20 @@ static char __log_buf[__LOG_BUF_LEN] __aligned(LOG_ALIGN);
 static char *log_buf = __log_buf;
 static u32 log_buf_len = __LOG_BUF_LEN;
 
+#ifdef CONFIG_TOI_INCREMENTAL
+void toi_set_logbuf_untracked(void)
+{
+    int i;
+    struct page *log_buf_start_page = virt_to_page(__log_buf);
+
+    printk("Not protecting kernel printk log buffer (%p-%p).\n",
+            __log_buf, __log_buf + __LOG_BUF_LEN);
+
+    for (i = 0; i < (1 << (CONFIG_LOG_BUF_SHIFT - PAGE_SHIFT)); i++)
+        SetPageTOI_Untracked(log_buf_start_page + i);
+}
+#endif
+
 /* Return log buffer address */
 char *log_buf_addr_get(void)
 {
diff --git a/kernel/smpboot.c b/kernel/smpboot.c
index d264f59bf..28c8e736d 100644
--- a/kernel/smpboot.c
+++ b/kernel/smpboot.c
@@ -174,7 +174,7 @@ __smpboot_create_thread(struct smp_hotplug_thread *ht, unsigned int cpu)
 	if (tsk)
 		return 0;
 
-	td = kzalloc_node(sizeof(*td), GFP_KERNEL, cpu_to_node(cpu));
+	td = kzalloc_node(sizeof(*td), GFP_KERNEL | ___GFP_TOI_NOTRACK, cpu_to_node(cpu));
 	if (!td)
 		return -ENOMEM;
 	td->cpu = cpu;
diff --git a/mm/debug.c b/mm/debug.c
index f05b2d5d6..5c6da0ffd 100644
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -40,6 +40,12 @@ static const struct trace_print_flags pageflag_names[] = {
 #ifdef CONFIG_MEMORY_FAILURE
 	{1UL << PG_hwpoison,		"hwpoison"	},
 #endif
+#ifdef CONFIG_TOI_INCREMENTAL
+	{1UL << PG_toi_untracked,	"toi_untracked"	},
+	{1UL << PG_toi_ro,		"toi_ro"	},
+	{1UL << PG_toi_cbw,		"toi_cbw"	},
+	{1UL << PG_toi_dirty,		"toi_dirty"	},
+#endif
 #if defined(CONFIG_IDLE_PAGE_TRACKING) && defined(CONFIG_64BIT)
 	{1UL << PG_young,		"young"		},
 	{1UL << PG_idle,		"idle"		},
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 838ca8bb6..58bc48250 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -62,6 +62,7 @@
 #include <linux/hugetlb.h>
 #include <linux/sched/rt.h>
 #include <linux/page_owner.h>
+#include <linux/tuxonice.h>
 #include <linux/kthread.h>
 
 #include <asm/sections.h>
@@ -751,6 +752,12 @@ static inline int free_pages_check(struct page *page)
 	if (unlikely(page->mem_cgroup))
 		bad_reason = "page still charged to cgroup";
 #endif
+        if (unlikely(PageTOI_Untracked(page))) {
+            // Make it writable and included in image if allocated.
+            ClearPageTOI_Untracked(page);
+            // If it gets allocated, it will be dirty from TOI's POV.
+            SetPageTOI_Dirty(page);
+        }
 	if (unlikely(bad_reason)) {
 		bad_page(page, bad_reason, bad_flags);
 		return 1;
@@ -1390,6 +1397,11 @@ static int prep_new_page(struct page *page, unsigned int order, gfp_t gfp_flags,
 		struct page *p = page + i;
 		if (unlikely(check_new_page(p)))
 			return 1;
+                if (unlikely(toi_incremental_support() && gfp_flags & ___GFP_TOI_NOTRACK)) {
+                    // Make the page writable if it's protected, and set it to be untracked.
+                    SetPageTOI_Untracked(p);
+                    toi_make_writable(init_mm.pgd, (unsigned long) page_address(p));
+                }
 	}
 
 	set_page_private(page, 0);
diff --git a/mm/percpu.c b/mm/percpu.c
index 998607adf..2f040d0b8 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -125,6 +125,7 @@ static int pcpu_nr_units __read_mostly;
 static int pcpu_atom_size __read_mostly;
 static int pcpu_nr_slots __read_mostly;
 static size_t pcpu_chunk_struct_size __read_mostly;
+static int pcpu_pfns;
 
 /* cpus with the lowest and highest unit addresses */
 static unsigned int pcpu_low_unit_cpu __read_mostly;
@@ -1790,6 +1791,7 @@ static struct pcpu_alloc_info * __init pcpu_build_alloc_info(
 	/* calculate size_sum and ensure dyn_size is enough for early alloc */
 	size_sum = PFN_ALIGN(static_size + reserved_size +
 			    max_t(size_t, dyn_size, PERCPU_DYNAMIC_EARLY_SIZE));
+        pcpu_pfns = PFN_DOWN(size_sum);
 	dyn_size = size_sum - static_size - reserved_size;
 
 	/*
@@ -2277,6 +2279,22 @@ void __init percpu_init_late(void)
 	}
 }
 
+#ifdef CONFIG_TOI_INCREMENTAL
+/*
+ * It doesn't matter if we mark an extra page as untracked (and therefore
+ * always save it in incremental images).
+ */
+void toi_mark_per_cpus_pages_untracked(void)
+{
+    int i;
+
+    struct page *page = virt_to_page(pcpu_base_addr);
+
+    for (i = 0; i < pcpu_pfns; i++)
+        SetPageTOI_Untracked(page + i);
+}
+#endif
+
 /*
  * Percpu allocator is initialized early during boot when neither slab or
  * workqueue is available.  Plug async management until everything is up
diff --git a/mm/shmem.c b/mm/shmem.c
index 440e2a7e6..f64ab5f8c 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1500,7 +1500,7 @@ static int shmem_mmap(struct file *file, struct vm_area_struct *vma)
 }
 
 static struct inode *shmem_get_inode(struct super_block *sb, const struct inode *dir,
-				     umode_t mode, dev_t dev, unsigned long flags)
+				     umode_t mode, dev_t dev, unsigned long flags, int atomic_copy)
 {
 	struct inode *inode;
 	struct shmem_inode_info *info;
@@ -1521,6 +1521,8 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode
 		spin_lock_init(&info->lock);
 		info->seals = F_SEAL_SEAL;
 		info->flags = flags & VM_NORESERVE;
+		if (atomic_copy)
+			inode->i_flags |= S_ATOMIC_COPY;
 		INIT_LIST_HEAD(&info->swaplist);
 		simple_xattrs_init(&info->xattrs);
 		cache_no_acl(inode);
@@ -2310,7 +2312,7 @@ shmem_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
 	struct inode *inode;
 	int error = -ENOSPC;
 
-	inode = shmem_get_inode(dir->i_sb, dir, mode, dev, VM_NORESERVE);
+	inode = shmem_get_inode(dir->i_sb, dir, mode, dev, VM_NORESERVE, 0);
 	if (inode) {
 		error = simple_acl_create(dir, inode);
 		if (error)
@@ -2339,7 +2341,7 @@ shmem_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
 	struct inode *inode;
 	int error = -ENOSPC;
 
-	inode = shmem_get_inode(dir->i_sb, dir, mode, 0, VM_NORESERVE);
+	inode = shmem_get_inode(dir->i_sb, dir, mode, 0, VM_NORESERVE, 0);
 	if (inode) {
 		error = security_inode_init_security(inode, dir,
 						     NULL,
@@ -2531,7 +2533,7 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s
 	if (len > PAGE_CACHE_SIZE)
 		return -ENAMETOOLONG;
 
-	inode = shmem_get_inode(dir->i_sb, dir, S_IFLNK|S_IRWXUGO, 0, VM_NORESERVE);
+	inode = shmem_get_inode(dir->i_sb, dir, S_IFLNK|S_IRWXUGO, 0, VM_NORESERVE, 0);
 	if (!inode)
 		return -ENOSPC;
 
@@ -3010,7 +3012,7 @@ SYSCALL_DEFINE2(memfd_create,
 		goto err_name;
 	}
 
-	file = shmem_file_setup(name, 0, VM_NORESERVE);
+	file = shmem_file_setup(name, 0, VM_NORESERVE, 0);
 	if (IS_ERR(file)) {
 		error = PTR_ERR(file);
 		goto err_fd;
@@ -3101,7 +3103,7 @@ int shmem_fill_super(struct super_block *sb, void *data, int silent)
 	sb->s_flags |= MS_POSIXACL;
 #endif
 
-	inode = shmem_get_inode(sb, NULL, S_IFDIR | sbinfo->mode, 0, VM_NORESERVE);
+	inode = shmem_get_inode(sb, NULL, S_IFDIR | sbinfo->mode, 0, VM_NORESERVE, 0);
 	if (!inode)
 		goto failed;
 	inode->i_uid = sbinfo->uid;
@@ -3357,7 +3359,7 @@ EXPORT_SYMBOL_GPL(shmem_truncate_range);
 
 #define shmem_vm_ops				generic_file_vm_ops
 #define shmem_file_operations			ramfs_file_operations
-#define shmem_get_inode(sb, dir, mode, dev, flags)	ramfs_get_inode(sb, dir, mode, dev)
+#define shmem_get_inode(sb, dir, mode, dev, flags, atomic_copy)	ramfs_get_inode(sb, dir, mode, dev)
 #define shmem_acct_size(flags, size)		0
 #define shmem_unacct_size(flags, size)		do {} while (0)
 
@@ -3370,7 +3372,8 @@ static struct dentry_operations anon_ops = {
 };
 
 static struct file *__shmem_file_setup(const char *name, loff_t size,
-				       unsigned long flags, unsigned int i_flags)
+				       unsigned long flags, unsigned int i_flags,
+				       int atomic_copy)
 {
 	struct file *res;
 	struct inode *inode;
@@ -3399,7 +3402,7 @@ static struct file *__shmem_file_setup(const char *name, loff_t size,
 	d_set_d_op(path.dentry, &anon_ops);
 
 	res = ERR_PTR(-ENOSPC);
-	inode = shmem_get_inode(sb, NULL, S_IFREG | S_IRWXUGO, 0, flags);
+	inode = shmem_get_inode(sb, NULL, S_IFREG | S_IRWXUGO, 0, flags, atomic_copy);
 	if (!inode)
 		goto put_memory;
 
@@ -3435,9 +3438,9 @@ put_path:
  * @size: size to be set for the file
  * @flags: VM_NORESERVE suppresses pre-accounting of the entire object size
  */
-struct file *shmem_kernel_file_setup(const char *name, loff_t size, unsigned long flags)
+struct file *shmem_kernel_file_setup(const char *name, loff_t size, unsigned long flags, int atomic_copy)
 {
-	return __shmem_file_setup(name, size, flags, S_PRIVATE);
+	return __shmem_file_setup(name, size, flags, S_PRIVATE, atomic_copy);
 }
 
 /**
@@ -3446,9 +3449,9 @@ struct file *shmem_kernel_file_setup(const char *name, loff_t size, unsigned lon
  * @size: size to be set for the file
  * @flags: VM_NORESERVE suppresses pre-accounting of the entire object size
  */
-struct file *shmem_file_setup(const char *name, loff_t size, unsigned long flags)
+struct file *shmem_file_setup(const char *name, loff_t size, unsigned long flags, int atomic_copy)
 {
-	return __shmem_file_setup(name, size, flags, 0);
+	return __shmem_file_setup(name, size, flags, 0, atomic_copy);
 }
 EXPORT_SYMBOL_GPL(shmem_file_setup);
 
@@ -3467,7 +3470,7 @@ int shmem_zero_setup(struct vm_area_struct *vma)
 	 * accessible to the user through its mapping, use S_PRIVATE flag to
 	 * bypass file security, in the same way as shmem_kernel_file_setup().
 	 */
-	file = __shmem_file_setup("dev/zero", size, vma->vm_flags, S_PRIVATE);
+	file = __shmem_file_setup("dev/zero", size, vma->vm_flags, S_PRIVATE, 0);
 	if (IS_ERR(file))
 		return PTR_ERR(file);
 
diff --git a/mm/slub.c b/mm/slub.c
index d8fbd4a6e..5328e64b9 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1379,7 +1379,7 @@ static inline struct page *alloc_slab_page(struct kmem_cache *s,
 	struct page *page;
 	int order = oo_order(oo);
 
-	flags |= __GFP_NOTRACK;
+	flags |= (__GFP_NOTRACK | ___GFP_TOI_NOTRACK);
 
 	if (node == NUMA_NO_NODE)
 		page = alloc_pages(flags, order);
@@ -3543,7 +3543,7 @@ static void *kmalloc_large_node(size_t size, gfp_t flags, int node)
 	struct page *page;
 	void *ptr = NULL;
 
-	flags |= __GFP_COMP | __GFP_NOTRACK;
+	flags |= __GFP_COMP | __GFP_NOTRACK | __GFP_TOI_NOTRACK;
 	page = alloc_kmem_pages_node(node, flags, get_order(size));
 	if (page)
 		ptr = page_address(page);
diff --git a/mm/swapfile.c b/mm/swapfile.c
index d2c37365e..98d348347 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -9,6 +9,7 @@
 #include <linux/hugetlb.h>
 #include <linux/mman.h>
 #include <linux/slab.h>
+#include <linux/export.h>
 #include <linux/kernel_stat.h>
 #include <linux/swap.h>
 #include <linux/vmalloc.h>
@@ -43,7 +44,6 @@
 static bool swap_count_continued(struct swap_info_struct *, pgoff_t,
 				 unsigned char);
 static void free_swap_count_continuations(struct swap_info_struct *);
-static sector_t map_swap_entry(swp_entry_t, struct block_device**);
 
 DEFINE_SPINLOCK(swap_lock);
 static unsigned int nr_swapfiles;
@@ -719,6 +719,60 @@ swp_entry_t get_swap_page_of_type(int type)
 	return (swp_entry_t) {0};
 }
 
+static unsigned int find_next_to_unuse(struct swap_info_struct *si,
+					unsigned int prev, bool frontswap);
+
+void get_swap_range_of_type(int type, swp_entry_t *start, swp_entry_t *end,
+		unsigned int limit)
+{
+	struct swap_info_struct *si;
+	pgoff_t start_at;
+	unsigned int i;
+
+	*start = swp_entry(0, 0);
+	*end = swp_entry(0, 0);
+	si = swap_info[type];
+	spin_lock(&si->lock);
+	if (si && (si->flags & SWP_WRITEOK)) {
+		atomic_long_dec(&nr_swap_pages);
+		/* This is called for allocating swap entry, not cache */
+		start_at = scan_swap_map(si, 1);
+		if (start_at) {
+			unsigned long stop_at = find_next_to_unuse(si, start_at, 0);
+			if (stop_at > start_at)
+				stop_at--;
+			else
+				stop_at = si->max - 1;
+			if (stop_at - start_at + 1 > limit)
+				stop_at = min_t(unsigned int,
+						start_at + limit - 1,
+						si->max - 1);
+			/* Mark them used */
+			for (i = start_at; i <= stop_at; i++)
+				si->swap_map[i] = 1;
+			/* first page already done above */
+			si->inuse_pages += stop_at - start_at;
+
+			atomic_long_sub(stop_at - start_at, &nr_swap_pages);
+			if (start_at == si->lowest_bit)
+				si->lowest_bit = stop_at + 1;
+			if (stop_at == si->highest_bit)
+				si->highest_bit = start_at - 1;
+			if (si->inuse_pages == si->pages) {
+				si->lowest_bit = si->max;
+				si->highest_bit = 0;
+			}
+			for (i = start_at + 1; i <= stop_at; i++)
+				inc_cluster_info_page(si, si->cluster_info, i);
+			si->cluster_next = stop_at + 1;
+			*start = swp_entry(type, start_at);
+			*end = swp_entry(type, stop_at);
+		} else
+			atomic_long_inc(&nr_swap_pages);
+	}
+	spin_unlock(&si->lock);
+}
+
 static struct swap_info_struct *swap_info_get(swp_entry_t entry)
 {
 	struct swap_info_struct *p;
@@ -1607,7 +1661,7 @@ static void drain_mmlist(void)
  * Note that the type of this function is sector_t, but it returns page offset
  * into the bdev, not sector offset.
  */
-static sector_t map_swap_entry(swp_entry_t entry, struct block_device **bdev)
+sector_t map_swap_entry(swp_entry_t entry, struct block_device **bdev)
 {
 	struct swap_info_struct *sis;
 	struct swap_extent *start_se;
@@ -2738,8 +2792,14 @@ pgoff_t __page_file_index(struct page *page)
 	VM_BUG_ON_PAGE(!PageSwapCache(page), page);
 	return swp_offset(swap);
 }
+
 EXPORT_SYMBOL_GPL(__page_file_index);
 
+struct swap_info_struct *get_swap_info_struct(unsigned type)
+{
+	return swap_info[type];
+}
+
 /*
  * add_swap_count_continuation - called when a swap count is duplicated
  * beyond SWAP_MAP_MAX, it allocates a new page and links that to the entry's
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 71b1c2994..f406a4765 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1475,7 +1475,7 @@ static int too_many_isolated(struct zone *zone, int file,
 {
 	unsigned long inactive, isolated;
 
-	if (current_is_kswapd())
+	if (current_is_kswapd() || sc->hibernation_mode)
 		return 0;
 
 	if (!sane_reclaim(sc))
@@ -2345,6 +2345,9 @@ static inline bool should_continue_reclaim(struct zone *zone,
 	unsigned long pages_for_compaction;
 	unsigned long inactive_lru_pages;
 
+	if (nr_reclaimed && nr_scanned && sc->nr_to_reclaim >= sc->nr_reclaimed)
+		return true;
+
 	/* If not in reclaim/compaction mode, stop */
 	if (!in_reclaim_compaction(sc))
 		return false;
@@ -2659,6 +2662,12 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
 	unsigned long total_scanned = 0;
 	unsigned long writeback_threshold;
 	bool zones_reclaimable;
+
+#ifdef CONFIG_FREEZER
+	if (unlikely(pm_freezing && !sc->hibernation_mode))
+		return 0;
+#endif
+
 retry:
 	delayacct_freepages_start();
 
@@ -3540,6 +3549,11 @@ void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx)
 	if (!populated_zone(zone))
 		return;
 
+#ifdef CONFIG_FREEZER
+	if (pm_freezing)
+		return;
+#endif
+
 	if (!cpuset_zone_allowed(zone, GFP_KERNEL | __GFP_HARDWALL))
 		return;
 	pgdat = zone->zone_pgdat;
@@ -3565,7 +3579,7 @@ void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx)
  * LRU order by reclaiming preferentially
  * inactive > active > active referenced > active mapped
  */
-unsigned long shrink_all_memory(unsigned long nr_to_reclaim)
+unsigned long shrink_memory_mask(unsigned long nr_to_reclaim, gfp_t mask)
 {
 	struct reclaim_state reclaim_state;
 	struct scan_control sc = {
@@ -3594,6 +3608,11 @@ unsigned long shrink_all_memory(unsigned long nr_to_reclaim)
 
 	return nr_reclaimed;
 }
+
+unsigned long shrink_all_memory(unsigned long nr_to_reclaim)
+{
+	return shrink_memory_mask(nr_to_reclaim, GFP_HIGHUSER_MOVABLE);
+}
 #endif /* CONFIG_HIBERNATION */
 
 /* It's optimal to keep kswapds on the same CPUs as their memory, but
diff --git a/scripts/tuxonice_output_to_csv.sh b/scripts/tuxonice_output_to_csv.sh
new file mode 100644
index 000000000..b96e6803b
--- /dev/null
+++ b/scripts/tuxonice_output_to_csv.sh
@@ -0,0 +1,35 @@
+#!/bin/bash
+
+cat $1 | grep "\*TOI\*" | cut -b 22- | sed "s/ /,/g" | sed "s/\.//" | sort -n > $1.tmp
+COLUMNS=$(cat $1.tmp | awk -F ',' ' { print $2 } ' | sort | uniq)
+echo -n "pfn," > $1.tmp2
+for NAME in $COLUMNS; do
+    echo -n "$NAME," >> $1.tmp2
+done
+echo >> $1.tmp2
+FIRST=1
+declare -A data
+while IFS=, read -r pfn column value; do
+    if [ $FIRST -eq 1 ]; then
+        FIRST=0
+        LAST_PFN=$pfn
+    fi
+    if [ $pfn -ne $LAST_PFN ]; then
+        echo -n "$LAST_PFN," >> $1.tmp2;
+        for NAME in $COLUMNS; do
+            echo -n "${data[$NAME]}," >> $1.tmp2
+        done
+        data=( )
+        echo >> $1.tmp2
+        LAST_PFN=$pfn
+    fi
+    if [ -z "$value" ]; then
+        data[$column]=X
+    else
+        data[$column]=$value
+    fi
+done < $1.tmp
+mv $1.tmp2 $1.csv
+rm $1.tmp
+LIBREOFFICE=$(which libreoffice)
+[ -n "$LIBREOFFICE" ] && libreoffice $1.csv &
diff --git a/security/keys/big_key.c b/security/keys/big_key.c
index 907c1522e..83dce8acf 100644
--- a/security/keys/big_key.c
+++ b/security/keys/big_key.c
@@ -78,7 +78,7 @@ int big_key_preparse(struct key_preparsed_payload *prep)
 		 *
 		 * TODO: Encrypt the stored data with a temporary key.
 		 */
-		file = shmem_kernel_file_setup("", datalen, 0);
+		file = shmem_kernel_file_setup("", datalen, 0, 0);
 		if (IS_ERR(file)) {
 			ret = PTR_ERR(file);
 			goto error;