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-rw-r--r--kernel/power/tuxonice_io.c1932
1 files changed, 1932 insertions, 0 deletions
diff --git a/kernel/power/tuxonice_io.c b/kernel/power/tuxonice_io.c
new file mode 100644
index 000000000..91b0c4fd0
--- /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;
+}