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>
33 #include <linux/ktime.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 */
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 = rb_entry(*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 static struct block_device *hib_resume_bdev;
217 struct hib_bio_batch {
219 wait_queue_head_t wait;
223 static void hib_init_batch(struct hib_bio_batch *hb)
225 atomic_set(&hb->count, 0);
226 init_waitqueue_head(&hb->wait);
230 static void hib_end_io(struct bio *bio, int error)
232 struct hib_bio_batch *hb = bio->bi_private;
233 const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
234 struct page *page = bio->bi_io_vec[0].bv_page;
236 if (!uptodate || error) {
237 printk(KERN_ALERT "Read-error on swap-device (%u:%u:%Lu)\n",
238 imajor(bio->bi_bdev->bd_inode),
239 iminor(bio->bi_bdev->bd_inode),
240 (unsigned long long)bio->bi_iter.bi_sector);
246 if (bio_data_dir(bio) == WRITE)
249 if (error && !hb->error)
251 if (atomic_dec_and_test(&hb->count))
257 static int hib_submit_io(int rw, pgoff_t page_off, void *addr,
258 struct hib_bio_batch *hb)
260 struct page *page = virt_to_page(addr);
264 bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1);
265 bio->bi_iter.bi_sector = page_off * (PAGE_SIZE >> 9);
266 bio->bi_bdev = hib_resume_bdev;
268 if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
269 printk(KERN_ERR "PM: Adding page to bio failed at %llu\n",
270 (unsigned long long)bio->bi_iter.bi_sector);
276 bio->bi_end_io = hib_end_io;
277 bio->bi_private = hb;
278 atomic_inc(&hb->count);
281 error = submit_bio_wait(rw, bio);
288 static int hib_wait_io(struct hib_bio_batch *hb)
290 wait_event(hb->wait, atomic_read(&hb->count) == 0);
298 static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
302 hib_submit_io(READ_SYNC, swsusp_resume_block, swsusp_header, NULL);
303 if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||
304 !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {
305 memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);
306 memcpy(swsusp_header->sig, HIBERNATE_SIG, 10);
307 swsusp_header->image = handle->first_sector;
308 swsusp_header->flags = flags;
309 if (flags & SF_CRC32_MODE)
310 swsusp_header->crc32 = handle->crc32;
311 error = hib_submit_io(WRITE_SYNC, swsusp_resume_block,
312 swsusp_header, NULL);
314 printk(KERN_ERR "PM: Swap header not found!\n");
321 * swsusp_swap_check - check if the resume device is a swap device
322 * and get its index (if so)
324 * This is called before saving image
326 static int swsusp_swap_check(void)
330 res = swap_type_of(swsusp_resume_device, swsusp_resume_block,
336 res = blkdev_get(hib_resume_bdev, FMODE_WRITE, NULL);
340 res = set_blocksize(hib_resume_bdev, PAGE_SIZE);
342 blkdev_put(hib_resume_bdev, FMODE_WRITE);
348 * write_page - Write one page to given swap location.
349 * @buf: Address we're writing.
350 * @offset: Offset of the swap page we're writing to.
351 * @hb: bio completion batch
354 static int write_page(void *buf, sector_t offset, struct hib_bio_batch *hb)
363 src = (void *)__get_free_page(__GFP_WAIT | __GFP_NOWARN |
368 ret = hib_wait_io(hb); /* Free pages */
371 src = (void *)__get_free_page(__GFP_WAIT |
378 hb = NULL; /* Go synchronous */
385 return hib_submit_io(WRITE_SYNC, offset, src, hb);
388 static void release_swap_writer(struct swap_map_handle *handle)
391 free_page((unsigned long)handle->cur);
395 static int get_swap_writer(struct swap_map_handle *handle)
399 ret = swsusp_swap_check();
402 printk(KERN_ERR "PM: Cannot find swap device, try "
406 handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL);
411 handle->cur_swap = alloc_swapdev_block(root_swap);
412 if (!handle->cur_swap) {
417 handle->reqd_free_pages = reqd_free_pages();
418 handle->first_sector = handle->cur_swap;
421 release_swap_writer(handle);
423 swsusp_close(FMODE_WRITE);
427 static int swap_write_page(struct swap_map_handle *handle, void *buf,
428 struct hib_bio_batch *hb)
435 offset = alloc_swapdev_block(root_swap);
436 error = write_page(buf, offset, hb);
439 handle->cur->entries[handle->k++] = offset;
440 if (handle->k >= MAP_PAGE_ENTRIES) {
441 offset = alloc_swapdev_block(root_swap);
444 handle->cur->next_swap = offset;
445 error = write_page(handle->cur, handle->cur_swap, hb);
448 clear_page(handle->cur);
449 handle->cur_swap = offset;
452 if (hb && low_free_pages() <= handle->reqd_free_pages) {
453 error = hib_wait_io(hb);
457 * Recalculate the number of required free pages, to
458 * make sure we never take more than half.
460 handle->reqd_free_pages = reqd_free_pages();
467 static int flush_swap_writer(struct swap_map_handle *handle)
469 if (handle->cur && handle->cur_swap)
470 return write_page(handle->cur, handle->cur_swap, NULL);
475 static int swap_writer_finish(struct swap_map_handle *handle,
476 unsigned int flags, int error)
479 flush_swap_writer(handle);
480 printk(KERN_INFO "PM: S");
481 error = mark_swapfiles(handle, flags);
486 free_all_swap_pages(root_swap);
487 release_swap_writer(handle);
488 swsusp_close(FMODE_WRITE);
493 /* We need to remember how much compressed data we need to read. */
494 #define LZO_HEADER sizeof(size_t)
496 /* Number of pages/bytes we'll compress at one time. */
497 #define LZO_UNC_PAGES 32
498 #define LZO_UNC_SIZE (LZO_UNC_PAGES * PAGE_SIZE)
500 /* Number of pages/bytes we need for compressed data (worst case). */
501 #define LZO_CMP_PAGES DIV_ROUND_UP(lzo1x_worst_compress(LZO_UNC_SIZE) + \
502 LZO_HEADER, PAGE_SIZE)
503 #define LZO_CMP_SIZE (LZO_CMP_PAGES * PAGE_SIZE)
505 /* Maximum number of threads for compression/decompression. */
506 #define LZO_THREADS 3
508 /* Minimum/maximum number of pages for read buffering. */
509 #define LZO_MIN_RD_PAGES 1024
510 #define LZO_MAX_RD_PAGES 8192
514 * save_image - save the suspend image data
517 static int save_image(struct swap_map_handle *handle,
518 struct snapshot_handle *snapshot,
519 unsigned int nr_to_write)
525 struct hib_bio_batch hb;
531 printk(KERN_INFO "PM: Saving image data pages (%u pages)...\n",
533 m = nr_to_write / 10;
539 ret = snapshot_read_next(snapshot);
542 ret = swap_write_page(handle, data_of(*snapshot), &hb);
546 printk(KERN_INFO "PM: Image saving progress: %3d%%\n",
550 err2 = hib_wait_io(&hb);
555 printk(KERN_INFO "PM: Image saving done.\n");
556 swsusp_show_speed(start, stop, nr_to_write, "Wrote");
561 * Structure used for CRC32.
564 struct task_struct *thr; /* thread */
565 atomic_t ready; /* ready to start flag */
566 atomic_t stop; /* ready to stop flag */
567 unsigned run_threads; /* nr current threads */
568 wait_queue_head_t go; /* start crc update */
569 wait_queue_head_t done; /* crc update done */
570 u32 *crc32; /* points to handle's crc32 */
571 size_t *unc_len[LZO_THREADS]; /* uncompressed lengths */
572 unsigned char *unc[LZO_THREADS]; /* uncompressed data */
576 * CRC32 update function that runs in its own thread.
578 static int crc32_threadfn(void *data)
580 struct crc_data *d = data;
584 wait_event(d->go, atomic_read(&d->ready) ||
585 kthread_should_stop());
586 if (kthread_should_stop()) {
588 atomic_set(&d->stop, 1);
592 atomic_set(&d->ready, 0);
594 for (i = 0; i < d->run_threads; i++)
595 *d->crc32 = crc32_le(*d->crc32,
596 d->unc[i], *d->unc_len[i]);
597 atomic_set(&d->stop, 1);
603 * Structure used for LZO data compression.
606 struct task_struct *thr; /* thread */
607 atomic_t ready; /* ready to start flag */
608 atomic_t stop; /* ready to stop flag */
609 int ret; /* return code */
610 wait_queue_head_t go; /* start compression */
611 wait_queue_head_t done; /* compression done */
612 size_t unc_len; /* uncompressed length */
613 size_t cmp_len; /* compressed length */
614 unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */
615 unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */
616 unsigned char wrk[LZO1X_1_MEM_COMPRESS]; /* compression workspace */
620 * Compression function that runs in its own thread.
622 static int lzo_compress_threadfn(void *data)
624 struct cmp_data *d = data;
627 wait_event(d->go, atomic_read(&d->ready) ||
628 kthread_should_stop());
629 if (kthread_should_stop()) {
632 atomic_set(&d->stop, 1);
636 atomic_set(&d->ready, 0);
638 d->ret = lzo1x_1_compress(d->unc, d->unc_len,
639 d->cmp + LZO_HEADER, &d->cmp_len,
641 atomic_set(&d->stop, 1);
648 * save_image_lzo - Save the suspend image data compressed with LZO.
649 * @handle: Swap map handle to use for saving the image.
650 * @snapshot: Image to read data from.
651 * @nr_to_write: Number of pages to save.
653 static int save_image_lzo(struct swap_map_handle *handle,
654 struct snapshot_handle *snapshot,
655 unsigned int nr_to_write)
661 struct hib_bio_batch hb;
665 unsigned thr, run_threads, nr_threads;
666 unsigned char *page = NULL;
667 struct cmp_data *data = NULL;
668 struct crc_data *crc = NULL;
673 * We'll limit the number of threads for compression to limit memory
676 nr_threads = num_online_cpus() - 1;
677 nr_threads = clamp_val(nr_threads, 1, LZO_THREADS);
679 page = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
681 printk(KERN_ERR "PM: Failed to allocate LZO page\n");
686 data = vmalloc(sizeof(*data) * nr_threads);
688 printk(KERN_ERR "PM: Failed to allocate LZO data\n");
692 for (thr = 0; thr < nr_threads; thr++)
693 memset(&data[thr], 0, offsetof(struct cmp_data, go));
695 crc = kmalloc(sizeof(*crc), GFP_KERNEL);
697 printk(KERN_ERR "PM: Failed to allocate crc\n");
701 memset(crc, 0, offsetof(struct crc_data, go));
704 * Start the compression threads.
706 for (thr = 0; thr < nr_threads; thr++) {
707 init_waitqueue_head(&data[thr].go);
708 init_waitqueue_head(&data[thr].done);
710 data[thr].thr = kthread_run(lzo_compress_threadfn,
712 "image_compress/%u", thr);
713 if (IS_ERR(data[thr].thr)) {
714 data[thr].thr = NULL;
716 "PM: Cannot start compression threads\n");
723 * Start the CRC32 thread.
725 init_waitqueue_head(&crc->go);
726 init_waitqueue_head(&crc->done);
729 crc->crc32 = &handle->crc32;
730 for (thr = 0; thr < nr_threads; thr++) {
731 crc->unc[thr] = data[thr].unc;
732 crc->unc_len[thr] = &data[thr].unc_len;
735 crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
736 if (IS_ERR(crc->thr)) {
738 printk(KERN_ERR "PM: Cannot start CRC32 thread\n");
744 * Adjust the number of required free pages after all allocations have
745 * been done. We don't want to run out of pages when writing.
747 handle->reqd_free_pages = reqd_free_pages();
750 "PM: Using %u thread(s) for compression.\n"
751 "PM: Compressing and saving image data (%u pages)...\n",
752 nr_threads, nr_to_write);
753 m = nr_to_write / 10;
759 for (thr = 0; thr < nr_threads; thr++) {
760 for (off = 0; off < LZO_UNC_SIZE; off += PAGE_SIZE) {
761 ret = snapshot_read_next(snapshot);
768 memcpy(data[thr].unc + off,
769 data_of(*snapshot), PAGE_SIZE);
773 "PM: Image saving progress: "
781 data[thr].unc_len = off;
783 atomic_set(&data[thr].ready, 1);
784 wake_up(&data[thr].go);
790 crc->run_threads = thr;
791 atomic_set(&crc->ready, 1);
794 for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
795 wait_event(data[thr].done,
796 atomic_read(&data[thr].stop));
797 atomic_set(&data[thr].stop, 0);
802 printk(KERN_ERR "PM: LZO compression failed\n");
806 if (unlikely(!data[thr].cmp_len ||
808 lzo1x_worst_compress(data[thr].unc_len))) {
810 "PM: Invalid LZO compressed length\n");
815 *(size_t *)data[thr].cmp = data[thr].cmp_len;
818 * Given we are writing one page at a time to disk, we
819 * copy that much from the buffer, although the last
820 * bit will likely be smaller than full page. This is
821 * OK - we saved the length of the compressed data, so
822 * any garbage at the end will be discarded when we
826 off < LZO_HEADER + data[thr].cmp_len;
828 memcpy(page, data[thr].cmp + off, PAGE_SIZE);
830 ret = swap_write_page(handle, page, &hb);
836 wait_event(crc->done, atomic_read(&crc->stop));
837 atomic_set(&crc->stop, 0);
841 err2 = hib_wait_io(&hb);
846 printk(KERN_INFO "PM: Image saving done.\n");
847 swsusp_show_speed(start, stop, nr_to_write, "Wrote");
851 kthread_stop(crc->thr);
855 for (thr = 0; thr < nr_threads; thr++)
857 kthread_stop(data[thr].thr);
860 if (page) free_page((unsigned long)page);
866 * enough_swap - Make sure we have enough swap to save the image.
868 * Returns TRUE or FALSE after checking the total amount of swap
869 * space avaiable from the resume partition.
872 static int enough_swap(unsigned int nr_pages, unsigned int flags)
874 unsigned int free_swap = count_swap_pages(root_swap, 1);
875 unsigned int required;
877 pr_debug("PM: Free swap pages: %u\n", free_swap);
879 required = PAGES_FOR_IO + nr_pages;
880 return free_swap > required;
884 * swsusp_write - Write entire image and metadata.
885 * @flags: flags to pass to the "boot" kernel in the image header
887 * It is important _NOT_ to umount filesystems at this point. We want
888 * them synced (in case something goes wrong) but we DO not want to mark
889 * filesystem clean: it is not. (And it does not matter, if we resume
890 * correctly, we'll mark system clean, anyway.)
893 int swsusp_write(unsigned int flags)
895 struct swap_map_handle handle;
896 struct snapshot_handle snapshot;
897 struct swsusp_info *header;
901 pages = snapshot_get_image_size();
902 error = get_swap_writer(&handle);
904 printk(KERN_ERR "PM: Cannot get swap writer\n");
907 if (flags & SF_NOCOMPRESS_MODE) {
908 if (!enough_swap(pages, flags)) {
909 printk(KERN_ERR "PM: Not enough free swap\n");
914 memset(&snapshot, 0, sizeof(struct snapshot_handle));
915 error = snapshot_read_next(&snapshot);
916 if (error < PAGE_SIZE) {
922 header = (struct swsusp_info *)data_of(snapshot);
923 error = swap_write_page(&handle, header, NULL);
925 error = (flags & SF_NOCOMPRESS_MODE) ?
926 save_image(&handle, &snapshot, pages - 1) :
927 save_image_lzo(&handle, &snapshot, pages - 1);
930 error = swap_writer_finish(&handle, flags, error);
935 * The following functions allow us to read data using a swap map
936 * in a file-alike way
939 static void release_swap_reader(struct swap_map_handle *handle)
941 struct swap_map_page_list *tmp;
943 while (handle->maps) {
944 if (handle->maps->map)
945 free_page((unsigned long)handle->maps->map);
947 handle->maps = handle->maps->next;
953 static int get_swap_reader(struct swap_map_handle *handle,
954 unsigned int *flags_p)
957 struct swap_map_page_list *tmp, *last;
960 *flags_p = swsusp_header->flags;
962 if (!swsusp_header->image) /* how can this happen? */
966 last = handle->maps = NULL;
967 offset = swsusp_header->image;
969 tmp = kmalloc(sizeof(*handle->maps), GFP_KERNEL);
971 release_swap_reader(handle);
974 memset(tmp, 0, sizeof(*tmp));
981 tmp->map = (struct swap_map_page *)
982 __get_free_page(__GFP_WAIT | __GFP_HIGH);
984 release_swap_reader(handle);
988 error = hib_submit_io(READ_SYNC, offset, tmp->map, NULL);
990 release_swap_reader(handle);
993 offset = tmp->map->next_swap;
996 handle->cur = handle->maps->map;
1000 static int swap_read_page(struct swap_map_handle *handle, void *buf,
1001 struct hib_bio_batch *hb)
1005 struct swap_map_page_list *tmp;
1009 offset = handle->cur->entries[handle->k];
1012 error = hib_submit_io(READ_SYNC, offset, buf, hb);
1015 if (++handle->k >= MAP_PAGE_ENTRIES) {
1017 free_page((unsigned long)handle->maps->map);
1019 handle->maps = handle->maps->next;
1022 release_swap_reader(handle);
1024 handle->cur = handle->maps->map;
1029 static int swap_reader_finish(struct swap_map_handle *handle)
1031 release_swap_reader(handle);
1037 * load_image - load the image using the swap map handle
1038 * @handle and the snapshot handle @snapshot
1039 * (assume there are @nr_pages pages to load)
1042 static int load_image(struct swap_map_handle *handle,
1043 struct snapshot_handle *snapshot,
1044 unsigned int nr_to_read)
1050 struct hib_bio_batch hb;
1054 hib_init_batch(&hb);
1056 printk(KERN_INFO "PM: Loading image data pages (%u pages)...\n",
1058 m = nr_to_read / 10;
1062 start = ktime_get();
1064 ret = snapshot_write_next(snapshot);
1067 ret = swap_read_page(handle, data_of(*snapshot), &hb);
1070 if (snapshot->sync_read)
1071 ret = hib_wait_io(&hb);
1074 if (!(nr_pages % m))
1075 printk(KERN_INFO "PM: Image loading progress: %3d%%\n",
1079 err2 = hib_wait_io(&hb);
1084 printk(KERN_INFO "PM: Image loading done.\n");
1085 snapshot_write_finalize(snapshot);
1086 if (!snapshot_image_loaded(snapshot))
1089 swsusp_show_speed(start, stop, nr_to_read, "Read");
1094 * Structure used for LZO data decompression.
1097 struct task_struct *thr; /* thread */
1098 atomic_t ready; /* ready to start flag */
1099 atomic_t stop; /* ready to stop flag */
1100 int ret; /* return code */
1101 wait_queue_head_t go; /* start decompression */
1102 wait_queue_head_t done; /* decompression done */
1103 size_t unc_len; /* uncompressed length */
1104 size_t cmp_len; /* compressed length */
1105 unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */
1106 unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */
1110 * Deompression function that runs in its own thread.
1112 static int lzo_decompress_threadfn(void *data)
1114 struct dec_data *d = data;
1117 wait_event(d->go, atomic_read(&d->ready) ||
1118 kthread_should_stop());
1119 if (kthread_should_stop()) {
1122 atomic_set(&d->stop, 1);
1126 atomic_set(&d->ready, 0);
1128 d->unc_len = LZO_UNC_SIZE;
1129 d->ret = lzo1x_decompress_safe(d->cmp + LZO_HEADER, d->cmp_len,
1130 d->unc, &d->unc_len);
1131 atomic_set(&d->stop, 1);
1138 * load_image_lzo - Load compressed image data and decompress them with LZO.
1139 * @handle: Swap map handle to use for loading data.
1140 * @snapshot: Image to copy uncompressed data into.
1141 * @nr_to_read: Number of pages to load.
1143 static int load_image_lzo(struct swap_map_handle *handle,
1144 struct snapshot_handle *snapshot,
1145 unsigned int nr_to_read)
1150 struct hib_bio_batch hb;
1155 unsigned i, thr, run_threads, nr_threads;
1156 unsigned ring = 0, pg = 0, ring_size = 0,
1157 have = 0, want, need, asked = 0;
1158 unsigned long read_pages = 0;
1159 unsigned char **page = NULL;
1160 struct dec_data *data = NULL;
1161 struct crc_data *crc = NULL;
1163 hib_init_batch(&hb);
1166 * We'll limit the number of threads for decompression to limit memory
1169 nr_threads = num_online_cpus() - 1;
1170 nr_threads = clamp_val(nr_threads, 1, LZO_THREADS);
1172 page = vmalloc(sizeof(*page) * LZO_MAX_RD_PAGES);
1174 printk(KERN_ERR "PM: Failed to allocate LZO page\n");
1179 data = vmalloc(sizeof(*data) * nr_threads);
1181 printk(KERN_ERR "PM: Failed to allocate LZO data\n");
1185 for (thr = 0; thr < nr_threads; thr++)
1186 memset(&data[thr], 0, offsetof(struct dec_data, go));
1188 crc = kmalloc(sizeof(*crc), GFP_KERNEL);
1190 printk(KERN_ERR "PM: Failed to allocate crc\n");
1194 memset(crc, 0, offsetof(struct crc_data, go));
1197 * Start the decompression threads.
1199 for (thr = 0; thr < nr_threads; thr++) {
1200 init_waitqueue_head(&data[thr].go);
1201 init_waitqueue_head(&data[thr].done);
1203 data[thr].thr = kthread_run(lzo_decompress_threadfn,
1205 "image_decompress/%u", thr);
1206 if (IS_ERR(data[thr].thr)) {
1207 data[thr].thr = NULL;
1209 "PM: Cannot start decompression threads\n");
1216 * Start the CRC32 thread.
1218 init_waitqueue_head(&crc->go);
1219 init_waitqueue_head(&crc->done);
1222 crc->crc32 = &handle->crc32;
1223 for (thr = 0; thr < nr_threads; thr++) {
1224 crc->unc[thr] = data[thr].unc;
1225 crc->unc_len[thr] = &data[thr].unc_len;
1228 crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
1229 if (IS_ERR(crc->thr)) {
1231 printk(KERN_ERR "PM: Cannot start CRC32 thread\n");
1237 * Set the number of pages for read buffering.
1238 * This is complete guesswork, because we'll only know the real
1239 * picture once prepare_image() is called, which is much later on
1240 * during the image load phase. We'll assume the worst case and
1241 * say that none of the image pages are from high memory.
1243 if (low_free_pages() > snapshot_get_image_size())
1244 read_pages = (low_free_pages() - snapshot_get_image_size()) / 2;
1245 read_pages = clamp_val(read_pages, LZO_MIN_RD_PAGES, LZO_MAX_RD_PAGES);
1247 for (i = 0; i < read_pages; i++) {
1248 page[i] = (void *)__get_free_page(i < LZO_CMP_PAGES ?
1249 __GFP_WAIT | __GFP_HIGH :
1250 __GFP_WAIT | __GFP_NOWARN |
1254 if (i < LZO_CMP_PAGES) {
1257 "PM: Failed to allocate LZO pages\n");
1265 want = ring_size = i;
1268 "PM: Using %u thread(s) for decompression.\n"
1269 "PM: Loading and decompressing image data (%u pages)...\n",
1270 nr_threads, nr_to_read);
1271 m = nr_to_read / 10;
1275 start = ktime_get();
1277 ret = snapshot_write_next(snapshot);
1282 for (i = 0; !eof && i < want; i++) {
1283 ret = swap_read_page(handle, page[ring], &hb);
1286 * On real read error, finish. On end of data,
1287 * set EOF flag and just exit the read loop.
1290 handle->cur->entries[handle->k]) {
1297 if (++ring >= ring_size)
1304 * We are out of data, wait for some more.
1310 ret = hib_wait_io(&hb);
1319 if (crc->run_threads) {
1320 wait_event(crc->done, atomic_read(&crc->stop));
1321 atomic_set(&crc->stop, 0);
1322 crc->run_threads = 0;
1325 for (thr = 0; have && thr < nr_threads; thr++) {
1326 data[thr].cmp_len = *(size_t *)page[pg];
1327 if (unlikely(!data[thr].cmp_len ||
1329 lzo1x_worst_compress(LZO_UNC_SIZE))) {
1331 "PM: Invalid LZO compressed length\n");
1336 need = DIV_ROUND_UP(data[thr].cmp_len + LZO_HEADER,
1347 off < LZO_HEADER + data[thr].cmp_len;
1349 memcpy(data[thr].cmp + off,
1350 page[pg], PAGE_SIZE);
1353 if (++pg >= ring_size)
1357 atomic_set(&data[thr].ready, 1);
1358 wake_up(&data[thr].go);
1362 * Wait for more data while we are decompressing.
1364 if (have < LZO_CMP_PAGES && asked) {
1365 ret = hib_wait_io(&hb);
1374 for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
1375 wait_event(data[thr].done,
1376 atomic_read(&data[thr].stop));
1377 atomic_set(&data[thr].stop, 0);
1379 ret = data[thr].ret;
1383 "PM: LZO decompression failed\n");
1387 if (unlikely(!data[thr].unc_len ||
1388 data[thr].unc_len > LZO_UNC_SIZE ||
1389 data[thr].unc_len & (PAGE_SIZE - 1))) {
1391 "PM: Invalid LZO uncompressed length\n");
1397 off < data[thr].unc_len; off += PAGE_SIZE) {
1398 memcpy(data_of(*snapshot),
1399 data[thr].unc + off, PAGE_SIZE);
1401 if (!(nr_pages % m))
1403 "PM: Image loading progress: "
1408 ret = snapshot_write_next(snapshot);
1410 crc->run_threads = thr + 1;
1411 atomic_set(&crc->ready, 1);
1418 crc->run_threads = thr;
1419 atomic_set(&crc->ready, 1);
1424 if (crc->run_threads) {
1425 wait_event(crc->done, atomic_read(&crc->stop));
1426 atomic_set(&crc->stop, 0);
1430 printk(KERN_INFO "PM: Image loading done.\n");
1431 snapshot_write_finalize(snapshot);
1432 if (!snapshot_image_loaded(snapshot))
1435 if (swsusp_header->flags & SF_CRC32_MODE) {
1436 if(handle->crc32 != swsusp_header->crc32) {
1438 "PM: Invalid image CRC32!\n");
1444 swsusp_show_speed(start, stop, nr_to_read, "Read");
1446 for (i = 0; i < ring_size; i++)
1447 free_page((unsigned long)page[i]);
1450 kthread_stop(crc->thr);
1454 for (thr = 0; thr < nr_threads; thr++)
1456 kthread_stop(data[thr].thr);
1465 * swsusp_read - read the hibernation image.
1466 * @flags_p: flags passed by the "frozen" kernel in the image header should
1467 * be written into this memory location
1470 int swsusp_read(unsigned int *flags_p)
1473 struct swap_map_handle handle;
1474 struct snapshot_handle snapshot;
1475 struct swsusp_info *header;
1477 memset(&snapshot, 0, sizeof(struct snapshot_handle));
1478 error = snapshot_write_next(&snapshot);
1479 if (error < PAGE_SIZE)
1480 return error < 0 ? error : -EFAULT;
1481 header = (struct swsusp_info *)data_of(snapshot);
1482 error = get_swap_reader(&handle, flags_p);
1486 error = swap_read_page(&handle, header, NULL);
1488 error = (*flags_p & SF_NOCOMPRESS_MODE) ?
1489 load_image(&handle, &snapshot, header->pages - 1) :
1490 load_image_lzo(&handle, &snapshot, header->pages - 1);
1492 swap_reader_finish(&handle);
1495 pr_debug("PM: Image successfully loaded\n");
1497 pr_debug("PM: Error %d resuming\n", error);
1502 * swsusp_check - Check for swsusp signature in the resume device
1505 int swsusp_check(void)
1509 hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device,
1511 if (!IS_ERR(hib_resume_bdev)) {
1512 set_blocksize(hib_resume_bdev, PAGE_SIZE);
1513 clear_page(swsusp_header);
1514 error = hib_submit_io(READ_SYNC, swsusp_resume_block,
1515 swsusp_header, NULL);
1519 if (!memcmp(HIBERNATE_SIG, swsusp_header->sig, 10)) {
1520 memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10);
1521 /* Reset swap signature now */
1522 error = hib_submit_io(WRITE_SYNC, swsusp_resume_block,
1523 swsusp_header, NULL);
1530 blkdev_put(hib_resume_bdev, FMODE_READ);
1532 pr_debug("PM: Image signature found, resuming\n");
1534 error = PTR_ERR(hib_resume_bdev);
1538 pr_debug("PM: Image not found (code %d)\n", error);
1544 * swsusp_close - close swap device.
1547 void swsusp_close(fmode_t mode)
1549 if (IS_ERR(hib_resume_bdev)) {
1550 pr_debug("PM: Image device not initialised\n");
1554 blkdev_put(hib_resume_bdev, mode);
1558 * swsusp_unmark - Unmark swsusp signature in the resume device
1561 #ifdef CONFIG_SUSPEND
1562 int swsusp_unmark(void)
1566 hib_submit_io(READ_SYNC, swsusp_resume_block, swsusp_header, NULL);
1567 if (!memcmp(HIBERNATE_SIG,swsusp_header->sig, 10)) {
1568 memcpy(swsusp_header->sig,swsusp_header->orig_sig, 10);
1569 error = hib_submit_io(WRITE_SYNC, swsusp_resume_block,
1570 swsusp_header, NULL);
1572 printk(KERN_ERR "PM: Cannot find swsusp signature!\n");
1577 * We just returned from suspend, we don't need the image any more.
1579 free_all_swap_pages(root_swap);
1585 static int swsusp_header_init(void)
1587 swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);
1589 panic("Could not allocate memory for swsusp_header\n");
1593 core_initcall(swsusp_header_init);