2 * linux/kernel/power/swap.c
4 * This file provides functions for reading the suspend image from
5 * and writing it to a swap partition.
7 * Copyright (C) 1998,2001-2005 Pavel Machek <pavel@ucw.cz>
8 * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl>
9 * Copyright (C) 2010-2012 Bojan Smojver <bojan@rexursive.com>
11 * This file is released under the GPLv2.
15 #include <linux/module.h>
16 #include <linux/file.h>
17 #include <linux/delay.h>
18 #include <linux/bitops.h>
19 #include <linux/genhd.h>
20 #include <linux/device.h>
21 #include <linux/bio.h>
22 #include <linux/blkdev.h>
23 #include <linux/swap.h>
24 #include <linux/swapops.h>
26 #include <linux/slab.h>
27 #include <linux/lzo.h>
28 #include <linux/vmalloc.h>
29 #include <linux/cpumask.h>
30 #include <linux/atomic.h>
31 #include <linux/kthread.h>
32 #include <linux/crc32.h>
36 #define HIBERNATE_SIG "S1SUSPEND"
39 * The swap map is a data structure used for keeping track of each page
40 * written to a swap partition. It consists of many swap_map_page
41 * structures that contain each an array of MAP_PAGE_ENTRIES swap entries.
42 * These structures are stored on the swap and linked together with the
43 * help of the .next_swap member.
45 * The swap map is created during suspend. The swap map pages are
46 * allocated and populated one at a time, so we only need one memory
47 * page to set up the entire structure.
49 * During resume we pick up all swap_map_page structures into a list.
52 #define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(sector_t) - 1)
55 * Number of free pages that are not high.
57 static inline unsigned long low_free_pages(void)
59 return nr_free_pages() - nr_free_highpages();
63 * Number of pages required to be kept free while writing the image. Always
64 * half of all available low pages before the writing starts.
66 static inline unsigned long reqd_free_pages(void)
68 return low_free_pages() / 2;
71 struct swap_map_page {
72 sector_t entries[MAP_PAGE_ENTRIES];
76 struct swap_map_page_list {
77 struct swap_map_page *map;
78 struct swap_map_page_list *next;
82 * The swap_map_handle structure is used for handling swap in
86 struct swap_map_handle {
87 struct swap_map_page *cur;
88 struct swap_map_page_list *maps;
90 sector_t first_sector;
92 unsigned long reqd_free_pages;
96 struct swsusp_header {
97 char reserved[PAGE_SIZE - 20 - sizeof(sector_t) - sizeof(int) -
101 unsigned int flags; /* Flags to pass to the "boot" kernel */
104 } __attribute__((packed));
106 static struct swsusp_header *swsusp_header;
109 * The following functions are used for tracing the allocated
110 * swap pages, so that they can be freed in case of an error.
113 struct swsusp_extent {
119 static struct rb_root swsusp_extents = RB_ROOT;
121 static int swsusp_extents_insert(unsigned long swap_offset)
123 struct rb_node **new = &(swsusp_extents.rb_node);
124 struct rb_node *parent = NULL;
125 struct swsusp_extent *ext;
127 /* Figure out where to put the new node */
129 ext = container_of(*new, struct swsusp_extent, node);
131 if (swap_offset < ext->start) {
133 if (swap_offset == ext->start - 1) {
137 new = &((*new)->rb_left);
138 } else if (swap_offset > ext->end) {
140 if (swap_offset == ext->end + 1) {
144 new = &((*new)->rb_right);
146 /* It already is in the tree */
150 /* Add the new node and rebalance the tree. */
151 ext = kzalloc(sizeof(struct swsusp_extent), GFP_KERNEL);
155 ext->start = swap_offset;
156 ext->end = swap_offset;
157 rb_link_node(&ext->node, parent, new);
158 rb_insert_color(&ext->node, &swsusp_extents);
163 * alloc_swapdev_block - allocate a swap page and register that it has
164 * been allocated, so that it can be freed in case of an error.
167 sector_t alloc_swapdev_block(int swap)
169 unsigned long offset;
171 offset = swp_offset(get_swap_page_of_type(swap));
173 if (swsusp_extents_insert(offset))
174 swap_free(swp_entry(swap, offset));
176 return swapdev_block(swap, offset);
182 * free_all_swap_pages - free swap pages allocated for saving image data.
183 * It also frees the extents used to register which swap entries had been
187 void free_all_swap_pages(int swap)
189 struct rb_node *node;
191 while ((node = swsusp_extents.rb_node)) {
192 struct swsusp_extent *ext;
193 unsigned long offset;
195 ext = container_of(node, struct swsusp_extent, node);
196 rb_erase(node, &swsusp_extents);
197 for (offset = ext->start; offset <= ext->end; offset++)
198 swap_free(swp_entry(swap, offset));
204 int swsusp_swap_in_use(void)
206 return (swsusp_extents.rb_node != NULL);
213 static unsigned short root_swap = 0xffff;
214 struct block_device *hib_resume_bdev;
220 static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
224 hib_bio_read_page(swsusp_resume_block, swsusp_header, NULL);
225 if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||
226 !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {
227 memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);
228 memcpy(swsusp_header->sig, HIBERNATE_SIG, 10);
229 swsusp_header->image = handle->first_sector;
230 swsusp_header->flags = flags;
231 if (flags & SF_CRC32_MODE)
232 swsusp_header->crc32 = handle->crc32;
233 error = hib_bio_write_page(swsusp_resume_block,
234 swsusp_header, NULL);
236 printk(KERN_ERR "PM: Swap header not found!\n");
243 * swsusp_swap_check - check if the resume device is a swap device
244 * and get its index (if so)
246 * This is called before saving image
248 static int swsusp_swap_check(void)
252 res = swap_type_of(swsusp_resume_device, swsusp_resume_block,
258 res = blkdev_get(hib_resume_bdev, FMODE_WRITE, NULL);
262 res = set_blocksize(hib_resume_bdev, PAGE_SIZE);
264 blkdev_put(hib_resume_bdev, FMODE_WRITE);
270 * write_page - Write one page to given swap location.
271 * @buf: Address we're writing.
272 * @offset: Offset of the swap page we're writing to.
273 * @bio_chain: Link the next write BIO here
276 static int write_page(void *buf, sector_t offset, struct bio **bio_chain)
285 src = (void *)__get_free_page(__GFP_WAIT | __GFP_NOWARN |
290 ret = hib_wait_on_bio_chain(bio_chain); /* Free pages */
293 src = (void *)__get_free_page(__GFP_WAIT |
300 bio_chain = NULL; /* Go synchronous */
307 return hib_bio_write_page(offset, src, bio_chain);
310 static void release_swap_writer(struct swap_map_handle *handle)
313 free_page((unsigned long)handle->cur);
317 static int get_swap_writer(struct swap_map_handle *handle)
321 ret = swsusp_swap_check();
324 printk(KERN_ERR "PM: Cannot find swap device, try "
328 handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL);
333 handle->cur_swap = alloc_swapdev_block(root_swap);
334 if (!handle->cur_swap) {
339 handle->reqd_free_pages = reqd_free_pages();
340 handle->first_sector = handle->cur_swap;
343 release_swap_writer(handle);
345 swsusp_close(FMODE_WRITE);
349 static int swap_write_page(struct swap_map_handle *handle, void *buf,
350 struct bio **bio_chain)
357 offset = alloc_swapdev_block(root_swap);
358 error = write_page(buf, offset, bio_chain);
361 handle->cur->entries[handle->k++] = offset;
362 if (handle->k >= MAP_PAGE_ENTRIES) {
363 offset = alloc_swapdev_block(root_swap);
366 handle->cur->next_swap = offset;
367 error = write_page(handle->cur, handle->cur_swap, bio_chain);
370 clear_page(handle->cur);
371 handle->cur_swap = offset;
374 if (bio_chain && low_free_pages() <= handle->reqd_free_pages) {
375 error = hib_wait_on_bio_chain(bio_chain);
379 * Recalculate the number of required free pages, to
380 * make sure we never take more than half.
382 handle->reqd_free_pages = reqd_free_pages();
389 static int flush_swap_writer(struct swap_map_handle *handle)
391 if (handle->cur && handle->cur_swap)
392 return write_page(handle->cur, handle->cur_swap, NULL);
397 static int swap_writer_finish(struct swap_map_handle *handle,
398 unsigned int flags, int error)
401 flush_swap_writer(handle);
402 printk(KERN_INFO "PM: S");
403 error = mark_swapfiles(handle, flags);
408 free_all_swap_pages(root_swap);
409 release_swap_writer(handle);
410 swsusp_close(FMODE_WRITE);
415 /* We need to remember how much compressed data we need to read. */
416 #define LZO_HEADER sizeof(size_t)
418 /* Number of pages/bytes we'll compress at one time. */
419 #define LZO_UNC_PAGES 32
420 #define LZO_UNC_SIZE (LZO_UNC_PAGES * PAGE_SIZE)
422 /* Number of pages/bytes we need for compressed data (worst case). */
423 #define LZO_CMP_PAGES DIV_ROUND_UP(lzo1x_worst_compress(LZO_UNC_SIZE) + \
424 LZO_HEADER, PAGE_SIZE)
425 #define LZO_CMP_SIZE (LZO_CMP_PAGES * PAGE_SIZE)
427 /* Maximum number of threads for compression/decompression. */
428 #define LZO_THREADS 3
430 /* Minimum/maximum number of pages for read buffering. */
431 #define LZO_MIN_RD_PAGES 1024
432 #define LZO_MAX_RD_PAGES 8192
436 * save_image - save the suspend image data
439 static int save_image(struct swap_map_handle *handle,
440 struct snapshot_handle *snapshot,
441 unsigned int nr_to_write)
448 struct timeval start;
451 printk(KERN_INFO "PM: Saving image data pages (%u pages) ... ",
453 m = nr_to_write / 100;
458 do_gettimeofday(&start);
460 ret = snapshot_read_next(snapshot);
463 ret = swap_write_page(handle, data_of(*snapshot), &bio);
467 printk(KERN_CONT "\b\b\b\b%3d%%", nr_pages / m);
470 err2 = hib_wait_on_bio_chain(&bio);
471 do_gettimeofday(&stop);
475 printk(KERN_CONT "\b\b\b\bdone\n");
477 printk(KERN_CONT "\n");
478 swsusp_show_speed(&start, &stop, nr_to_write, "Wrote");
483 * Structure used for CRC32.
486 struct task_struct *thr; /* thread */
487 atomic_t ready; /* ready to start flag */
488 atomic_t stop; /* ready to stop flag */
489 unsigned run_threads; /* nr current threads */
490 wait_queue_head_t go; /* start crc update */
491 wait_queue_head_t done; /* crc update done */
492 u32 *crc32; /* points to handle's crc32 */
493 size_t *unc_len[LZO_THREADS]; /* uncompressed lengths */
494 unsigned char *unc[LZO_THREADS]; /* uncompressed data */
498 * CRC32 update function that runs in its own thread.
500 static int crc32_threadfn(void *data)
502 struct crc_data *d = data;
506 wait_event(d->go, atomic_read(&d->ready) ||
507 kthread_should_stop());
508 if (kthread_should_stop()) {
510 atomic_set(&d->stop, 1);
514 atomic_set(&d->ready, 0);
516 for (i = 0; i < d->run_threads; i++)
517 *d->crc32 = crc32_le(*d->crc32,
518 d->unc[i], *d->unc_len[i]);
519 atomic_set(&d->stop, 1);
525 * Structure used for LZO data compression.
528 struct task_struct *thr; /* thread */
529 atomic_t ready; /* ready to start flag */
530 atomic_t stop; /* ready to stop flag */
531 int ret; /* return code */
532 wait_queue_head_t go; /* start compression */
533 wait_queue_head_t done; /* compression done */
534 size_t unc_len; /* uncompressed length */
535 size_t cmp_len; /* compressed length */
536 unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */
537 unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */
538 unsigned char wrk[LZO1X_1_MEM_COMPRESS]; /* compression workspace */
542 * Compression function that runs in its own thread.
544 static int lzo_compress_threadfn(void *data)
546 struct cmp_data *d = data;
549 wait_event(d->go, atomic_read(&d->ready) ||
550 kthread_should_stop());
551 if (kthread_should_stop()) {
554 atomic_set(&d->stop, 1);
558 atomic_set(&d->ready, 0);
560 d->ret = lzo1x_1_compress(d->unc, d->unc_len,
561 d->cmp + LZO_HEADER, &d->cmp_len,
563 atomic_set(&d->stop, 1);
570 * save_image_lzo - Save the suspend image data compressed with LZO.
571 * @handle: Swap mam handle to use for saving the image.
572 * @snapshot: Image to read data from.
573 * @nr_to_write: Number of pages to save.
575 static int save_image_lzo(struct swap_map_handle *handle,
576 struct snapshot_handle *snapshot,
577 unsigned int nr_to_write)
584 struct timeval start;
587 unsigned thr, run_threads, nr_threads;
588 unsigned char *page = NULL;
589 struct cmp_data *data = NULL;
590 struct crc_data *crc = NULL;
593 * We'll limit the number of threads for compression to limit memory
596 nr_threads = num_online_cpus() - 1;
597 nr_threads = clamp_val(nr_threads, 1, LZO_THREADS);
599 page = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
601 printk(KERN_ERR "PM: Failed to allocate LZO page\n");
606 data = vmalloc(sizeof(*data) * nr_threads);
608 printk(KERN_ERR "PM: Failed to allocate LZO data\n");
612 for (thr = 0; thr < nr_threads; thr++)
613 memset(&data[thr], 0, offsetof(struct cmp_data, go));
615 crc = kmalloc(sizeof(*crc), GFP_KERNEL);
617 printk(KERN_ERR "PM: Failed to allocate crc\n");
621 memset(crc, 0, offsetof(struct crc_data, go));
624 * Start the compression threads.
626 for (thr = 0; thr < nr_threads; thr++) {
627 init_waitqueue_head(&data[thr].go);
628 init_waitqueue_head(&data[thr].done);
630 data[thr].thr = kthread_run(lzo_compress_threadfn,
632 "image_compress/%u", thr);
633 if (IS_ERR(data[thr].thr)) {
634 data[thr].thr = NULL;
636 "PM: Cannot start compression threads\n");
643 * Start the CRC32 thread.
645 init_waitqueue_head(&crc->go);
646 init_waitqueue_head(&crc->done);
649 crc->crc32 = &handle->crc32;
650 for (thr = 0; thr < nr_threads; thr++) {
651 crc->unc[thr] = data[thr].unc;
652 crc->unc_len[thr] = &data[thr].unc_len;
655 crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
656 if (IS_ERR(crc->thr)) {
658 printk(KERN_ERR "PM: Cannot start CRC32 thread\n");
664 * Adjust the number of required free pages after all allocations have
665 * been done. We don't want to run out of pages when writing.
667 handle->reqd_free_pages = reqd_free_pages();
670 "PM: Using %u thread(s) for compression.\n"
671 "PM: Compressing and saving image data (%u pages) ... ",
672 nr_threads, nr_to_write);
673 m = nr_to_write / 100;
678 do_gettimeofday(&start);
680 for (thr = 0; thr < nr_threads; thr++) {
681 for (off = 0; off < LZO_UNC_SIZE; off += PAGE_SIZE) {
682 ret = snapshot_read_next(snapshot);
689 memcpy(data[thr].unc + off,
690 data_of(*snapshot), PAGE_SIZE);
693 printk(KERN_CONT "\b\b\b\b%3d%%",
700 data[thr].unc_len = off;
702 atomic_set(&data[thr].ready, 1);
703 wake_up(&data[thr].go);
709 crc->run_threads = thr;
710 atomic_set(&crc->ready, 1);
713 for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
714 wait_event(data[thr].done,
715 atomic_read(&data[thr].stop));
716 atomic_set(&data[thr].stop, 0);
721 printk(KERN_ERR "PM: LZO compression failed\n");
725 if (unlikely(!data[thr].cmp_len ||
727 lzo1x_worst_compress(data[thr].unc_len))) {
729 "PM: Invalid LZO compressed length\n");
734 *(size_t *)data[thr].cmp = data[thr].cmp_len;
737 * Given we are writing one page at a time to disk, we
738 * copy that much from the buffer, although the last
739 * bit will likely be smaller than full page. This is
740 * OK - we saved the length of the compressed data, so
741 * any garbage at the end will be discarded when we
745 off < LZO_HEADER + data[thr].cmp_len;
747 memcpy(page, data[thr].cmp + off, PAGE_SIZE);
749 ret = swap_write_page(handle, page, &bio);
755 wait_event(crc->done, atomic_read(&crc->stop));
756 atomic_set(&crc->stop, 0);
760 err2 = hib_wait_on_bio_chain(&bio);
761 do_gettimeofday(&stop);
765 printk(KERN_CONT "\b\b\b\bdone\n");
767 printk(KERN_CONT "\n");
769 swsusp_show_speed(&start, &stop, nr_to_write, "Wrote");
773 kthread_stop(crc->thr);
777 for (thr = 0; thr < nr_threads; thr++)
779 kthread_stop(data[thr].thr);
782 if (page) free_page((unsigned long)page);
788 * enough_swap - Make sure we have enough swap to save the image.
790 * Returns TRUE or FALSE after checking the total amount of swap
791 * space avaiable from the resume partition.
794 static int enough_swap(unsigned int nr_pages, unsigned int flags)
796 unsigned int free_swap = count_swap_pages(root_swap, 1);
797 unsigned int required;
799 pr_debug("PM: Free swap pages: %u\n", free_swap);
801 required = PAGES_FOR_IO + nr_pages;
802 return free_swap > required;
806 * swsusp_write - Write entire image and metadata.
807 * @flags: flags to pass to the "boot" kernel in the image header
809 * It is important _NOT_ to umount filesystems at this point. We want
810 * them synced (in case something goes wrong) but we DO not want to mark
811 * filesystem clean: it is not. (And it does not matter, if we resume
812 * correctly, we'll mark system clean, anyway.)
815 int swsusp_write(unsigned int flags)
817 struct swap_map_handle handle;
818 struct snapshot_handle snapshot;
819 struct swsusp_info *header;
823 pages = snapshot_get_image_size();
824 error = get_swap_writer(&handle);
826 printk(KERN_ERR "PM: Cannot get swap writer\n");
829 if (flags & SF_NOCOMPRESS_MODE) {
830 if (!enough_swap(pages, flags)) {
831 printk(KERN_ERR "PM: Not enough free swap\n");
836 memset(&snapshot, 0, sizeof(struct snapshot_handle));
837 error = snapshot_read_next(&snapshot);
838 if (error < PAGE_SIZE) {
844 header = (struct swsusp_info *)data_of(snapshot);
845 error = swap_write_page(&handle, header, NULL);
847 error = (flags & SF_NOCOMPRESS_MODE) ?
848 save_image(&handle, &snapshot, pages - 1) :
849 save_image_lzo(&handle, &snapshot, pages - 1);
852 error = swap_writer_finish(&handle, flags, error);
857 * The following functions allow us to read data using a swap map
858 * in a file-alike way
861 static void release_swap_reader(struct swap_map_handle *handle)
863 struct swap_map_page_list *tmp;
865 while (handle->maps) {
866 if (handle->maps->map)
867 free_page((unsigned long)handle->maps->map);
869 handle->maps = handle->maps->next;
875 static int get_swap_reader(struct swap_map_handle *handle,
876 unsigned int *flags_p)
879 struct swap_map_page_list *tmp, *last;
882 *flags_p = swsusp_header->flags;
884 if (!swsusp_header->image) /* how can this happen? */
888 last = handle->maps = NULL;
889 offset = swsusp_header->image;
891 tmp = kmalloc(sizeof(*handle->maps), GFP_KERNEL);
893 release_swap_reader(handle);
896 memset(tmp, 0, sizeof(*tmp));
903 tmp->map = (struct swap_map_page *)
904 __get_free_page(__GFP_WAIT | __GFP_HIGH);
906 release_swap_reader(handle);
910 error = hib_bio_read_page(offset, tmp->map, NULL);
912 release_swap_reader(handle);
915 offset = tmp->map->next_swap;
918 handle->cur = handle->maps->map;
922 static int swap_read_page(struct swap_map_handle *handle, void *buf,
923 struct bio **bio_chain)
927 struct swap_map_page_list *tmp;
931 offset = handle->cur->entries[handle->k];
934 error = hib_bio_read_page(offset, buf, bio_chain);
937 if (++handle->k >= MAP_PAGE_ENTRIES) {
939 free_page((unsigned long)handle->maps->map);
941 handle->maps = handle->maps->next;
944 release_swap_reader(handle);
946 handle->cur = handle->maps->map;
951 static int swap_reader_finish(struct swap_map_handle *handle)
953 release_swap_reader(handle);
959 * load_image - load the image using the swap map handle
960 * @handle and the snapshot handle @snapshot
961 * (assume there are @nr_pages pages to load)
964 static int load_image(struct swap_map_handle *handle,
965 struct snapshot_handle *snapshot,
966 unsigned int nr_to_read)
970 struct timeval start;
976 printk(KERN_INFO "PM: Loading image data pages (%u pages) ... ",
978 m = nr_to_read / 100;
983 do_gettimeofday(&start);
985 ret = snapshot_write_next(snapshot);
988 ret = swap_read_page(handle, data_of(*snapshot), &bio);
991 if (snapshot->sync_read)
992 ret = hib_wait_on_bio_chain(&bio);
996 printk("\b\b\b\b%3d%%", nr_pages / m);
999 err2 = hib_wait_on_bio_chain(&bio);
1000 do_gettimeofday(&stop);
1004 printk("\b\b\b\bdone\n");
1005 snapshot_write_finalize(snapshot);
1006 if (!snapshot_image_loaded(snapshot))
1010 swsusp_show_speed(&start, &stop, nr_to_read, "Read");
1015 * Structure used for LZO data decompression.
1018 struct task_struct *thr; /* thread */
1019 atomic_t ready; /* ready to start flag */
1020 atomic_t stop; /* ready to stop flag */
1021 int ret; /* return code */
1022 wait_queue_head_t go; /* start decompression */
1023 wait_queue_head_t done; /* decompression done */
1024 size_t unc_len; /* uncompressed length */
1025 size_t cmp_len; /* compressed length */
1026 unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */
1027 unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */
1031 * Deompression function that runs in its own thread.
1033 static int lzo_decompress_threadfn(void *data)
1035 struct dec_data *d = data;
1038 wait_event(d->go, atomic_read(&d->ready) ||
1039 kthread_should_stop());
1040 if (kthread_should_stop()) {
1043 atomic_set(&d->stop, 1);
1047 atomic_set(&d->ready, 0);
1049 d->unc_len = LZO_UNC_SIZE;
1050 d->ret = lzo1x_decompress_safe(d->cmp + LZO_HEADER, d->cmp_len,
1051 d->unc, &d->unc_len);
1052 atomic_set(&d->stop, 1);
1059 * load_image_lzo - Load compressed image data and decompress them with LZO.
1060 * @handle: Swap map handle to use for loading data.
1061 * @snapshot: Image to copy uncompressed data into.
1062 * @nr_to_read: Number of pages to load.
1064 static int load_image_lzo(struct swap_map_handle *handle,
1065 struct snapshot_handle *snapshot,
1066 unsigned int nr_to_read)
1072 struct timeval start;
1073 struct timeval stop;
1076 unsigned i, thr, run_threads, nr_threads;
1077 unsigned ring = 0, pg = 0, ring_size = 0,
1078 have = 0, want, need, asked = 0;
1079 unsigned long read_pages = 0;
1080 unsigned char **page = NULL;
1081 struct dec_data *data = NULL;
1082 struct crc_data *crc = NULL;
1085 * We'll limit the number of threads for decompression to limit memory
1088 nr_threads = num_online_cpus() - 1;
1089 nr_threads = clamp_val(nr_threads, 1, LZO_THREADS);
1091 page = vmalloc(sizeof(*page) * LZO_MAX_RD_PAGES);
1093 printk(KERN_ERR "PM: Failed to allocate LZO page\n");
1098 data = vmalloc(sizeof(*data) * nr_threads);
1100 printk(KERN_ERR "PM: Failed to allocate LZO data\n");
1104 for (thr = 0; thr < nr_threads; thr++)
1105 memset(&data[thr], 0, offsetof(struct dec_data, go));
1107 crc = kmalloc(sizeof(*crc), GFP_KERNEL);
1109 printk(KERN_ERR "PM: Failed to allocate crc\n");
1113 memset(crc, 0, offsetof(struct crc_data, go));
1116 * Start the decompression threads.
1118 for (thr = 0; thr < nr_threads; thr++) {
1119 init_waitqueue_head(&data[thr].go);
1120 init_waitqueue_head(&data[thr].done);
1122 data[thr].thr = kthread_run(lzo_decompress_threadfn,
1124 "image_decompress/%u", thr);
1125 if (IS_ERR(data[thr].thr)) {
1126 data[thr].thr = NULL;
1128 "PM: Cannot start decompression threads\n");
1135 * Start the CRC32 thread.
1137 init_waitqueue_head(&crc->go);
1138 init_waitqueue_head(&crc->done);
1141 crc->crc32 = &handle->crc32;
1142 for (thr = 0; thr < nr_threads; thr++) {
1143 crc->unc[thr] = data[thr].unc;
1144 crc->unc_len[thr] = &data[thr].unc_len;
1147 crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
1148 if (IS_ERR(crc->thr)) {
1150 printk(KERN_ERR "PM: Cannot start CRC32 thread\n");
1156 * Set the number of pages for read buffering.
1157 * This is complete guesswork, because we'll only know the real
1158 * picture once prepare_image() is called, which is much later on
1159 * during the image load phase. We'll assume the worst case and
1160 * say that none of the image pages are from high memory.
1162 if (low_free_pages() > snapshot_get_image_size())
1163 read_pages = (low_free_pages() - snapshot_get_image_size()) / 2;
1164 read_pages = clamp_val(read_pages, LZO_MIN_RD_PAGES, LZO_MAX_RD_PAGES);
1166 for (i = 0; i < read_pages; i++) {
1167 page[i] = (void *)__get_free_page(i < LZO_CMP_PAGES ?
1168 __GFP_WAIT | __GFP_HIGH :
1169 __GFP_WAIT | __GFP_NOWARN |
1173 if (i < LZO_CMP_PAGES) {
1176 "PM: Failed to allocate LZO pages\n");
1184 want = ring_size = i;
1187 "PM: Using %u thread(s) for decompression.\n"
1188 "PM: Loading and decompressing image data (%u pages) ... ",
1189 nr_threads, nr_to_read);
1190 m = nr_to_read / 100;
1195 do_gettimeofday(&start);
1197 ret = snapshot_write_next(snapshot);
1202 for (i = 0; !eof && i < want; i++) {
1203 ret = swap_read_page(handle, page[ring], &bio);
1206 * On real read error, finish. On end of data,
1207 * set EOF flag and just exit the read loop.
1210 handle->cur->entries[handle->k]) {
1217 if (++ring >= ring_size)
1224 * We are out of data, wait for some more.
1230 ret = hib_wait_on_bio_chain(&bio);
1239 if (crc->run_threads) {
1240 wait_event(crc->done, atomic_read(&crc->stop));
1241 atomic_set(&crc->stop, 0);
1242 crc->run_threads = 0;
1245 for (thr = 0; have && thr < nr_threads; thr++) {
1246 data[thr].cmp_len = *(size_t *)page[pg];
1247 if (unlikely(!data[thr].cmp_len ||
1249 lzo1x_worst_compress(LZO_UNC_SIZE))) {
1251 "PM: Invalid LZO compressed length\n");
1256 need = DIV_ROUND_UP(data[thr].cmp_len + LZO_HEADER,
1267 off < LZO_HEADER + data[thr].cmp_len;
1269 memcpy(data[thr].cmp + off,
1270 page[pg], PAGE_SIZE);
1273 if (++pg >= ring_size)
1277 atomic_set(&data[thr].ready, 1);
1278 wake_up(&data[thr].go);
1282 * Wait for more data while we are decompressing.
1284 if (have < LZO_CMP_PAGES && asked) {
1285 ret = hib_wait_on_bio_chain(&bio);
1294 for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
1295 wait_event(data[thr].done,
1296 atomic_read(&data[thr].stop));
1297 atomic_set(&data[thr].stop, 0);
1299 ret = data[thr].ret;
1303 "PM: LZO decompression failed\n");
1307 if (unlikely(!data[thr].unc_len ||
1308 data[thr].unc_len > LZO_UNC_SIZE ||
1309 data[thr].unc_len & (PAGE_SIZE - 1))) {
1311 "PM: Invalid LZO uncompressed length\n");
1317 off < data[thr].unc_len; off += PAGE_SIZE) {
1318 memcpy(data_of(*snapshot),
1319 data[thr].unc + off, PAGE_SIZE);
1321 if (!(nr_pages % m))
1322 printk("\b\b\b\b%3d%%", nr_pages / m);
1325 ret = snapshot_write_next(snapshot);
1327 crc->run_threads = thr + 1;
1328 atomic_set(&crc->ready, 1);
1335 crc->run_threads = thr;
1336 atomic_set(&crc->ready, 1);
1341 if (crc->run_threads) {
1342 wait_event(crc->done, atomic_read(&crc->stop));
1343 atomic_set(&crc->stop, 0);
1345 do_gettimeofday(&stop);
1347 printk("\b\b\b\bdone\n");
1348 snapshot_write_finalize(snapshot);
1349 if (!snapshot_image_loaded(snapshot))
1352 if (swsusp_header->flags & SF_CRC32_MODE) {
1353 if(handle->crc32 != swsusp_header->crc32) {
1355 "PM: Invalid image CRC32!\n");
1362 swsusp_show_speed(&start, &stop, nr_to_read, "Read");
1364 for (i = 0; i < ring_size; i++)
1365 free_page((unsigned long)page[i]);
1368 kthread_stop(crc->thr);
1372 for (thr = 0; thr < nr_threads; thr++)
1374 kthread_stop(data[thr].thr);
1377 if (page) vfree(page);
1383 * swsusp_read - read the hibernation image.
1384 * @flags_p: flags passed by the "frozen" kernel in the image header should
1385 * be written into this memory location
1388 int swsusp_read(unsigned int *flags_p)
1391 struct swap_map_handle handle;
1392 struct snapshot_handle snapshot;
1393 struct swsusp_info *header;
1395 memset(&snapshot, 0, sizeof(struct snapshot_handle));
1396 error = snapshot_write_next(&snapshot);
1397 if (error < PAGE_SIZE)
1398 return error < 0 ? error : -EFAULT;
1399 header = (struct swsusp_info *)data_of(snapshot);
1400 error = get_swap_reader(&handle, flags_p);
1404 error = swap_read_page(&handle, header, NULL);
1406 error = (*flags_p & SF_NOCOMPRESS_MODE) ?
1407 load_image(&handle, &snapshot, header->pages - 1) :
1408 load_image_lzo(&handle, &snapshot, header->pages - 1);
1410 swap_reader_finish(&handle);
1413 pr_debug("PM: Image successfully loaded\n");
1415 pr_debug("PM: Error %d resuming\n", error);
1420 * swsusp_check - Check for swsusp signature in the resume device
1423 int swsusp_check(void)
1427 hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device,
1429 if (!IS_ERR(hib_resume_bdev)) {
1430 set_blocksize(hib_resume_bdev, PAGE_SIZE);
1431 clear_page(swsusp_header);
1432 error = hib_bio_read_page(swsusp_resume_block,
1433 swsusp_header, NULL);
1437 if (!memcmp(HIBERNATE_SIG, swsusp_header->sig, 10)) {
1438 memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10);
1439 /* Reset swap signature now */
1440 error = hib_bio_write_page(swsusp_resume_block,
1441 swsusp_header, NULL);
1448 blkdev_put(hib_resume_bdev, FMODE_READ);
1450 pr_debug("PM: Image signature found, resuming\n");
1452 error = PTR_ERR(hib_resume_bdev);
1456 pr_debug("PM: Image not found (code %d)\n", error);
1462 * swsusp_close - close swap device.
1465 void swsusp_close(fmode_t mode)
1467 if (IS_ERR(hib_resume_bdev)) {
1468 pr_debug("PM: Image device not initialised\n");
1472 blkdev_put(hib_resume_bdev, mode);
1475 static int swsusp_header_init(void)
1477 swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);
1479 panic("Could not allocate memory for swsusp_header\n");
1483 core_initcall(swsusp_header_init);