diff options
Diffstat (limited to 'kernel/power/tuxonice_bio_core.c')
| -rw-r--r-- | kernel/power/tuxonice_bio_core.c | 1937 |
1 files changed, 0 insertions, 1937 deletions
diff --git a/kernel/power/tuxonice_bio_core.c b/kernel/power/tuxonice_bio_core.c deleted file mode 100644 index bc27662d7..000000000 --- a/kernel/power/tuxonice_bio_core.c +++ /dev/null @@ -1,1937 +0,0 @@ -/* - * 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(0)); - 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; - - result = toi_bio_register_storage(); - - 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); |