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/buffer_head.h>
22 #include <linux/bio.h>
23 #include <linux/blkdev.h>
24 #include <linux/swap.h>
25 #include <linux/swapops.h>
27 #include <linux/slab.h>
28 #include <linux/lzo.h>
29 #include <linux/vmalloc.h>
30 #include <linux/cpumask.h>
31 #include <linux/atomic.h>
32 #include <linux/kthread.h>
33 #include <linux/crc32.h>
37 #define HIBERNATE_SIG "S1SUSPEND"
40 * The swap map is a data structure used for keeping track of each page
41 * written to a swap partition. It consists of many swap_map_page
42 * structures that contain each an array of MAP_PAGE_ENTRIES swap entries.
43 * These structures are stored on the swap and linked together with the
44 * help of the .next_swap member.
46 * The swap map is created during suspend. The swap map pages are
47 * allocated and populated one at a time, so we only need one memory
48 * page to set up the entire structure.
50 * During resume we pick up all swap_map_page structures into a list.
53 #define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(sector_t) - 1)
56 * Number of free pages that are not high.
58 static inline unsigned long low_free_pages(void)
60 return nr_free_pages() - nr_free_highpages();
64 * Number of pages required to be kept free while writing the image. Always
65 * half of all available low pages before the writing starts.
67 static inline unsigned long reqd_free_pages(void)
69 return low_free_pages() / 2;
72 struct swap_map_page {
73 sector_t entries[MAP_PAGE_ENTRIES];
77 struct swap_map_page_list {
78 struct swap_map_page *map;
79 struct swap_map_page_list *next;
83 * The swap_map_handle structure is used for handling swap in
87 struct swap_map_handle {
88 struct swap_map_page *cur;
89 struct swap_map_page_list *maps;
91 sector_t first_sector;
93 unsigned long reqd_free_pages;
97 struct swsusp_header {
98 char reserved[PAGE_SIZE - 20 - sizeof(sector_t) - sizeof(int) -
102 unsigned int flags; /* Flags to pass to the "boot" kernel */
105 } __attribute__((packed));
107 static struct swsusp_header *swsusp_header;
110 * The following functions are used for tracing the allocated
111 * swap pages, so that they can be freed in case of an error.
114 struct swsusp_extent {
120 static struct rb_root swsusp_extents = RB_ROOT;
122 static int swsusp_extents_insert(unsigned long swap_offset)
124 struct rb_node **new = &(swsusp_extents.rb_node);
125 struct rb_node *parent = NULL;
126 struct swsusp_extent *ext;
128 /* Figure out where to put the new node */
130 ext = container_of(*new, struct swsusp_extent, node);
132 if (swap_offset < ext->start) {
134 if (swap_offset == ext->start - 1) {
138 new = &((*new)->rb_left);
139 } else if (swap_offset > ext->end) {
141 if (swap_offset == ext->end + 1) {
145 new = &((*new)->rb_right);
147 /* It already is in the tree */
151 /* Add the new node and rebalance the tree. */
152 ext = kzalloc(sizeof(struct swsusp_extent), GFP_KERNEL);
156 ext->start = swap_offset;
157 ext->end = swap_offset;
158 rb_link_node(&ext->node, parent, new);
159 rb_insert_color(&ext->node, &swsusp_extents);
164 * alloc_swapdev_block - allocate a swap page and register that it has
165 * been allocated, so that it can be freed in case of an error.
168 sector_t alloc_swapdev_block(int swap)
170 unsigned long offset;
172 offset = swp_offset(get_swap_page_of_type(swap));
174 if (swsusp_extents_insert(offset))
175 swap_free(swp_entry(swap, offset));
177 return swapdev_block(swap, offset);
183 * free_all_swap_pages - free swap pages allocated for saving image data.
184 * It also frees the extents used to register which swap entries had been
188 void free_all_swap_pages(int swap)
190 struct rb_node *node;
192 while ((node = swsusp_extents.rb_node)) {
193 struct swsusp_extent *ext;
194 unsigned long offset;
196 ext = container_of(node, struct swsusp_extent, node);
197 rb_erase(node, &swsusp_extents);
198 for (offset = ext->start; offset <= ext->end; offset++)
199 swap_free(swp_entry(swap, offset));
205 int swsusp_swap_in_use(void)
207 return (swsusp_extents.rb_node != NULL);
214 static unsigned short root_swap = 0xffff;
215 struct block_device *hib_resume_bdev;
221 static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
225 hib_bio_read_page(swsusp_resume_block, swsusp_header, NULL);
226 if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||
227 !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {
228 memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);
229 memcpy(swsusp_header->sig, HIBERNATE_SIG, 10);
230 swsusp_header->image = handle->first_sector;
231 swsusp_header->flags = flags;
232 if (flags & SF_CRC32_MODE)
233 swsusp_header->crc32 = handle->crc32;
234 error = hib_bio_write_page(swsusp_resume_block,
235 swsusp_header, NULL);
237 printk(KERN_ERR "PM: Swap header not found!\n");
244 * swsusp_swap_check - check if the resume device is a swap device
245 * and get its index (if so)
247 * This is called before saving image
249 static int swsusp_swap_check(void)
253 res = swap_type_of(swsusp_resume_device, swsusp_resume_block,
259 res = blkdev_get(hib_resume_bdev, FMODE_WRITE, NULL);
263 res = set_blocksize(hib_resume_bdev, PAGE_SIZE);
265 blkdev_put(hib_resume_bdev, FMODE_WRITE);
271 * write_page - Write one page to given swap location.
272 * @buf: Address we're writing.
273 * @offset: Offset of the swap page we're writing to.
274 * @bio_chain: Link the next write BIO here
277 static int write_page(void *buf, sector_t offset, struct bio **bio_chain)
286 src = (void *)__get_free_page(__GFP_WAIT | __GFP_NOWARN |
291 ret = hib_wait_on_bio_chain(bio_chain); /* Free pages */
294 src = (void *)__get_free_page(__GFP_WAIT |
301 bio_chain = NULL; /* Go synchronous */
308 return hib_bio_write_page(offset, src, bio_chain);
311 static void release_swap_writer(struct swap_map_handle *handle)
314 free_page((unsigned long)handle->cur);
318 static int get_swap_writer(struct swap_map_handle *handle)
322 ret = swsusp_swap_check();
325 printk(KERN_ERR "PM: Cannot find swap device, try "
329 handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL);
334 handle->cur_swap = alloc_swapdev_block(root_swap);
335 if (!handle->cur_swap) {
340 handle->reqd_free_pages = reqd_free_pages();
341 handle->first_sector = handle->cur_swap;
344 release_swap_writer(handle);
346 swsusp_close(FMODE_WRITE);
350 static int swap_write_page(struct swap_map_handle *handle, void *buf,
351 struct bio **bio_chain)
358 offset = alloc_swapdev_block(root_swap);
359 error = write_page(buf, offset, bio_chain);
362 handle->cur->entries[handle->k++] = offset;
363 if (handle->k >= MAP_PAGE_ENTRIES) {
364 offset = alloc_swapdev_block(root_swap);
367 handle->cur->next_swap = offset;
368 error = write_page(handle->cur, handle->cur_swap, bio_chain);
371 clear_page(handle->cur);
372 handle->cur_swap = offset;
375 if (bio_chain && low_free_pages() <= handle->reqd_free_pages) {
376 error = hib_wait_on_bio_chain(bio_chain);
380 * Recalculate the number of required free pages, to
381 * make sure we never take more than half.
383 handle->reqd_free_pages = reqd_free_pages();
390 static int flush_swap_writer(struct swap_map_handle *handle)
392 if (handle->cur && handle->cur_swap)
393 return write_page(handle->cur, handle->cur_swap, NULL);
398 static int swap_writer_finish(struct swap_map_handle *handle,
399 unsigned int flags, int error)
402 flush_swap_writer(handle);
403 printk(KERN_INFO "PM: S");
404 error = mark_swapfiles(handle, flags);
409 free_all_swap_pages(root_swap);
410 release_swap_writer(handle);
411 swsusp_close(FMODE_WRITE);
416 /* We need to remember how much compressed data we need to read. */
417 #define LZO_HEADER sizeof(size_t)
419 /* Number of pages/bytes we'll compress at one time. */
420 #define LZO_UNC_PAGES 32
421 #define LZO_UNC_SIZE (LZO_UNC_PAGES * PAGE_SIZE)
423 /* Number of pages/bytes we need for compressed data (worst case). */
424 #define LZO_CMP_PAGES DIV_ROUND_UP(lzo1x_worst_compress(LZO_UNC_SIZE) + \
425 LZO_HEADER, PAGE_SIZE)
426 #define LZO_CMP_SIZE (LZO_CMP_PAGES * PAGE_SIZE)
428 /* Maximum number of threads for compression/decompression. */
429 #define LZO_THREADS 3
431 /* Minimum/maximum number of pages for read buffering. */
432 #define LZO_MIN_RD_PAGES 1024
433 #define LZO_MAX_RD_PAGES 8192
437 * save_image - save the suspend image data
440 static int save_image(struct swap_map_handle *handle,
441 struct snapshot_handle *snapshot,
442 unsigned int nr_to_write)
449 struct timeval start;
452 printk(KERN_INFO "PM: Saving image data pages (%u pages) ... ",
454 m = nr_to_write / 100;
459 do_gettimeofday(&start);
461 ret = snapshot_read_next(snapshot);
464 ret = swap_write_page(handle, data_of(*snapshot), &bio);
468 printk(KERN_CONT "\b\b\b\b%3d%%", nr_pages / m);
471 err2 = hib_wait_on_bio_chain(&bio);
472 do_gettimeofday(&stop);
476 printk(KERN_CONT "\b\b\b\bdone\n");
478 printk(KERN_CONT "\n");
479 swsusp_show_speed(&start, &stop, nr_to_write, "Wrote");
484 * Structure used for CRC32.
487 struct task_struct *thr; /* thread */
488 atomic_t ready; /* ready to start flag */
489 atomic_t stop; /* ready to stop flag */
490 unsigned run_threads; /* nr current threads */
491 wait_queue_head_t go; /* start crc update */
492 wait_queue_head_t done; /* crc update done */
493 u32 *crc32; /* points to handle's crc32 */
494 size_t *unc_len[LZO_THREADS]; /* uncompressed lengths */
495 unsigned char *unc[LZO_THREADS]; /* uncompressed data */
499 * CRC32 update function that runs in its own thread.
501 static int crc32_threadfn(void *data)
503 struct crc_data *d = data;
507 wait_event(d->go, atomic_read(&d->ready) ||
508 kthread_should_stop());
509 if (kthread_should_stop()) {
511 atomic_set(&d->stop, 1);
515 atomic_set(&d->ready, 0);
517 for (i = 0; i < d->run_threads; i++)
518 *d->crc32 = crc32_le(*d->crc32,
519 d->unc[i], *d->unc_len[i]);
520 atomic_set(&d->stop, 1);
526 * Structure used for LZO data compression.
529 struct task_struct *thr; /* thread */
530 atomic_t ready; /* ready to start flag */
531 atomic_t stop; /* ready to stop flag */
532 int ret; /* return code */
533 wait_queue_head_t go; /* start compression */
534 wait_queue_head_t done; /* compression done */
535 size_t unc_len; /* uncompressed length */
536 size_t cmp_len; /* compressed length */
537 unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */
538 unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */
539 unsigned char wrk[LZO1X_1_MEM_COMPRESS]; /* compression workspace */
543 * Compression function that runs in its own thread.
545 static int lzo_compress_threadfn(void *data)
547 struct cmp_data *d = data;
550 wait_event(d->go, atomic_read(&d->ready) ||
551 kthread_should_stop());
552 if (kthread_should_stop()) {
555 atomic_set(&d->stop, 1);
559 atomic_set(&d->ready, 0);
561 d->ret = lzo1x_1_compress(d->unc, d->unc_len,
562 d->cmp + LZO_HEADER, &d->cmp_len,
564 atomic_set(&d->stop, 1);
571 * save_image_lzo - Save the suspend image data compressed with LZO.
572 * @handle: Swap mam handle to use for saving the image.
573 * @snapshot: Image to read data from.
574 * @nr_to_write: Number of pages to save.
576 static int save_image_lzo(struct swap_map_handle *handle,
577 struct snapshot_handle *snapshot,
578 unsigned int nr_to_write)
585 struct timeval start;
588 unsigned thr, run_threads, nr_threads;
589 unsigned char *page = NULL;
590 struct cmp_data *data = NULL;
591 struct crc_data *crc = NULL;
594 * We'll limit the number of threads for compression to limit memory
597 nr_threads = num_online_cpus() - 1;
598 nr_threads = clamp_val(nr_threads, 1, LZO_THREADS);
600 page = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
602 printk(KERN_ERR "PM: Failed to allocate LZO page\n");
607 data = vmalloc(sizeof(*data) * nr_threads);
609 printk(KERN_ERR "PM: Failed to allocate LZO data\n");
613 for (thr = 0; thr < nr_threads; thr++)
614 memset(&data[thr], 0, offsetof(struct cmp_data, go));
616 crc = kmalloc(sizeof(*crc), GFP_KERNEL);
618 printk(KERN_ERR "PM: Failed to allocate crc\n");
622 memset(crc, 0, offsetof(struct crc_data, go));
625 * Start the compression threads.
627 for (thr = 0; thr < nr_threads; thr++) {
628 init_waitqueue_head(&data[thr].go);
629 init_waitqueue_head(&data[thr].done);
631 data[thr].thr = kthread_run(lzo_compress_threadfn,
633 "image_compress/%u", thr);
634 if (IS_ERR(data[thr].thr)) {
635 data[thr].thr = NULL;
637 "PM: Cannot start compression threads\n");
644 * Start the CRC32 thread.
646 init_waitqueue_head(&crc->go);
647 init_waitqueue_head(&crc->done);
650 crc->crc32 = &handle->crc32;
651 for (thr = 0; thr < nr_threads; thr++) {
652 crc->unc[thr] = data[thr].unc;
653 crc->unc_len[thr] = &data[thr].unc_len;
656 crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
657 if (IS_ERR(crc->thr)) {
659 printk(KERN_ERR "PM: Cannot start CRC32 thread\n");
665 * Adjust the number of required free pages after all allocations have
666 * been done. We don't want to run out of pages when writing.
668 handle->reqd_free_pages = reqd_free_pages();
671 "PM: Using %u thread(s) for compression.\n"
672 "PM: Compressing and saving image data (%u pages) ... ",
673 nr_threads, nr_to_write);
674 m = nr_to_write / 100;
679 do_gettimeofday(&start);
681 for (thr = 0; thr < nr_threads; thr++) {
682 for (off = 0; off < LZO_UNC_SIZE; off += PAGE_SIZE) {
683 ret = snapshot_read_next(snapshot);
690 memcpy(data[thr].unc + off,
691 data_of(*snapshot), PAGE_SIZE);
694 printk(KERN_CONT "\b\b\b\b%3d%%",
701 data[thr].unc_len = off;
703 atomic_set(&data[thr].ready, 1);
704 wake_up(&data[thr].go);
710 crc->run_threads = thr;
711 atomic_set(&crc->ready, 1);
714 for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
715 wait_event(data[thr].done,
716 atomic_read(&data[thr].stop));
717 atomic_set(&data[thr].stop, 0);
722 printk(KERN_ERR "PM: LZO compression failed\n");
726 if (unlikely(!data[thr].cmp_len ||
728 lzo1x_worst_compress(data[thr].unc_len))) {
730 "PM: Invalid LZO compressed length\n");
735 *(size_t *)data[thr].cmp = data[thr].cmp_len;
738 * Given we are writing one page at a time to disk, we
739 * copy that much from the buffer, although the last
740 * bit will likely be smaller than full page. This is
741 * OK - we saved the length of the compressed data, so
742 * any garbage at the end will be discarded when we
746 off < LZO_HEADER + data[thr].cmp_len;
748 memcpy(page, data[thr].cmp + off, PAGE_SIZE);
750 ret = swap_write_page(handle, page, &bio);
756 wait_event(crc->done, atomic_read(&crc->stop));
757 atomic_set(&crc->stop, 0);
761 err2 = hib_wait_on_bio_chain(&bio);
762 do_gettimeofday(&stop);
766 printk(KERN_CONT "\b\b\b\bdone\n");
768 printk(KERN_CONT "\n");
770 swsusp_show_speed(&start, &stop, nr_to_write, "Wrote");
774 kthread_stop(crc->thr);
778 for (thr = 0; thr < nr_threads; thr++)
780 kthread_stop(data[thr].thr);
783 if (page) free_page((unsigned long)page);
789 * enough_swap - Make sure we have enough swap to save the image.
791 * Returns TRUE or FALSE after checking the total amount of swap
792 * space avaiable from the resume partition.
795 static int enough_swap(unsigned int nr_pages, unsigned int flags)
797 unsigned int free_swap = count_swap_pages(root_swap, 1);
798 unsigned int required;
800 pr_debug("PM: Free swap pages: %u\n", free_swap);
802 required = PAGES_FOR_IO + ((flags & SF_NOCOMPRESS_MODE) ?
803 nr_pages : (nr_pages * LZO_CMP_PAGES) / LZO_UNC_PAGES + 1);
804 return free_swap > required;
808 * swsusp_write - Write entire image and metadata.
809 * @flags: flags to pass to the "boot" kernel in the image header
811 * It is important _NOT_ to umount filesystems at this point. We want
812 * them synced (in case something goes wrong) but we DO not want to mark
813 * filesystem clean: it is not. (And it does not matter, if we resume
814 * correctly, we'll mark system clean, anyway.)
817 int swsusp_write(unsigned int flags)
819 struct swap_map_handle handle;
820 struct snapshot_handle snapshot;
821 struct swsusp_info *header;
825 pages = snapshot_get_image_size();
826 error = get_swap_writer(&handle);
828 printk(KERN_ERR "PM: Cannot get swap writer\n");
831 if (!enough_swap(pages, flags)) {
832 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);