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 * When reading an {un,}compressed image, we may restore pages in place,
41 * in which case some architectures need these pages cleaning before they
42 * can be executed. We don't know which pages these may be, so clean the lot.
44 static bool clean_pages_on_read
;
45 static bool clean_pages_on_decompress
;
48 * The swap map is a data structure used for keeping track of each page
49 * written to a swap partition. It consists of many swap_map_page
50 * structures that contain each an array of MAP_PAGE_ENTRIES swap entries.
51 * These structures are stored on the swap and linked together with the
52 * help of the .next_swap member.
54 * The swap map is created during suspend. The swap map pages are
55 * allocated and populated one at a time, so we only need one memory
56 * page to set up the entire structure.
58 * During resume we pick up all swap_map_page structures into a list.
61 #define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(sector_t) - 1)
64 * Number of free pages that are not high.
66 static inline unsigned long low_free_pages(void)
68 return nr_free_pages() - nr_free_highpages();
72 * Number of pages required to be kept free while writing the image. Always
73 * half of all available low pages before the writing starts.
75 static inline unsigned long reqd_free_pages(void)
77 return low_free_pages() / 2;
80 struct swap_map_page
{
81 sector_t entries
[MAP_PAGE_ENTRIES
];
85 struct swap_map_page_list
{
86 struct swap_map_page
*map
;
87 struct swap_map_page_list
*next
;
91 * The swap_map_handle structure is used for handling swap in
95 struct swap_map_handle
{
96 struct swap_map_page
*cur
;
97 struct swap_map_page_list
*maps
;
99 sector_t first_sector
;
101 unsigned long reqd_free_pages
;
105 struct swsusp_header
{
106 char reserved
[PAGE_SIZE
- 20 - sizeof(sector_t
) - sizeof(int) -
110 unsigned int flags
; /* Flags to pass to the "boot" kernel */
115 static struct swsusp_header
*swsusp_header
;
118 * The following functions are used for tracing the allocated
119 * swap pages, so that they can be freed in case of an error.
122 struct swsusp_extent
{
128 static struct rb_root swsusp_extents
= RB_ROOT
;
130 static int swsusp_extents_insert(unsigned long swap_offset
)
132 struct rb_node
**new = &(swsusp_extents
.rb_node
);
133 struct rb_node
*parent
= NULL
;
134 struct swsusp_extent
*ext
;
136 /* Figure out where to put the new node */
138 ext
= rb_entry(*new, struct swsusp_extent
, node
);
140 if (swap_offset
< ext
->start
) {
142 if (swap_offset
== ext
->start
- 1) {
146 new = &((*new)->rb_left
);
147 } else if (swap_offset
> ext
->end
) {
149 if (swap_offset
== ext
->end
+ 1) {
153 new = &((*new)->rb_right
);
155 /* It already is in the tree */
159 /* Add the new node and rebalance the tree. */
160 ext
= kzalloc(sizeof(struct swsusp_extent
), GFP_KERNEL
);
164 ext
->start
= swap_offset
;
165 ext
->end
= swap_offset
;
166 rb_link_node(&ext
->node
, parent
, new);
167 rb_insert_color(&ext
->node
, &swsusp_extents
);
172 * alloc_swapdev_block - allocate a swap page and register that it has
173 * been allocated, so that it can be freed in case of an error.
176 sector_t
alloc_swapdev_block(int swap
)
178 unsigned long offset
;
180 offset
= swp_offset(get_swap_page_of_type(swap
));
182 if (swsusp_extents_insert(offset
))
183 swap_free(swp_entry(swap
, offset
));
185 return swapdev_block(swap
, offset
);
191 * free_all_swap_pages - free swap pages allocated for saving image data.
192 * It also frees the extents used to register which swap entries had been
196 void free_all_swap_pages(int swap
)
198 struct rb_node
*node
;
200 while ((node
= swsusp_extents
.rb_node
)) {
201 struct swsusp_extent
*ext
;
202 unsigned long offset
;
204 ext
= container_of(node
, struct swsusp_extent
, node
);
205 rb_erase(node
, &swsusp_extents
);
206 for (offset
= ext
->start
; offset
<= ext
->end
; offset
++)
207 swap_free(swp_entry(swap
, offset
));
213 int swsusp_swap_in_use(void)
215 return (swsusp_extents
.rb_node
!= NULL
);
222 static unsigned short root_swap
= 0xffff;
223 static struct block_device
*hib_resume_bdev
;
225 struct hib_bio_batch
{
227 wait_queue_head_t wait
;
231 static void hib_init_batch(struct hib_bio_batch
*hb
)
233 atomic_set(&hb
->count
, 0);
234 init_waitqueue_head(&hb
->wait
);
238 static void hib_end_io(struct bio
*bio
)
240 struct hib_bio_batch
*hb
= bio
->bi_private
;
241 struct page
*page
= bio
->bi_io_vec
[0].bv_page
;
244 printk(KERN_ALERT
"Read-error on swap-device (%u:%u:%Lu)\n",
245 imajor(bio
->bi_bdev
->bd_inode
),
246 iminor(bio
->bi_bdev
->bd_inode
),
247 (unsigned long long)bio
->bi_iter
.bi_sector
);
250 if (bio_data_dir(bio
) == WRITE
)
252 else if (clean_pages_on_read
)
253 flush_icache_range((unsigned long)page_address(page
),
254 (unsigned long)page_address(page
) + PAGE_SIZE
);
256 if (bio
->bi_error
&& !hb
->error
)
257 hb
->error
= bio
->bi_error
;
258 if (atomic_dec_and_test(&hb
->count
))
264 static int hib_submit_io(int rw
, pgoff_t page_off
, void *addr
,
265 struct hib_bio_batch
*hb
)
267 struct page
*page
= virt_to_page(addr
);
271 bio
= bio_alloc(__GFP_RECLAIM
| __GFP_HIGH
, 1);
272 bio
->bi_iter
.bi_sector
= page_off
* (PAGE_SIZE
>> 9);
273 bio
->bi_bdev
= hib_resume_bdev
;
275 if (bio_add_page(bio
, page
, PAGE_SIZE
, 0) < PAGE_SIZE
) {
276 printk(KERN_ERR
"PM: Adding page to bio failed at %llu\n",
277 (unsigned long long)bio
->bi_iter
.bi_sector
);
283 bio
->bi_end_io
= hib_end_io
;
284 bio
->bi_private
= hb
;
285 atomic_inc(&hb
->count
);
288 error
= submit_bio_wait(rw
, bio
);
295 static int hib_wait_io(struct hib_bio_batch
*hb
)
297 wait_event(hb
->wait
, atomic_read(&hb
->count
) == 0);
305 static int mark_swapfiles(struct swap_map_handle
*handle
, unsigned int flags
)
309 hib_submit_io(READ_SYNC
, swsusp_resume_block
, swsusp_header
, NULL
);
310 if (!memcmp("SWAP-SPACE",swsusp_header
->sig
, 10) ||
311 !memcmp("SWAPSPACE2",swsusp_header
->sig
, 10)) {
312 memcpy(swsusp_header
->orig_sig
,swsusp_header
->sig
, 10);
313 memcpy(swsusp_header
->sig
, HIBERNATE_SIG
, 10);
314 swsusp_header
->image
= handle
->first_sector
;
315 swsusp_header
->flags
= flags
;
316 if (flags
& SF_CRC32_MODE
)
317 swsusp_header
->crc32
= handle
->crc32
;
318 error
= hib_submit_io(WRITE_SYNC
, swsusp_resume_block
,
319 swsusp_header
, NULL
);
321 printk(KERN_ERR
"PM: Swap header not found!\n");
328 * swsusp_swap_check - check if the resume device is a swap device
329 * and get its index (if so)
331 * This is called before saving image
333 static int swsusp_swap_check(void)
337 res
= swap_type_of(swsusp_resume_device
, swsusp_resume_block
,
343 res
= blkdev_get(hib_resume_bdev
, FMODE_WRITE
, NULL
);
347 res
= set_blocksize(hib_resume_bdev
, PAGE_SIZE
);
349 blkdev_put(hib_resume_bdev
, FMODE_WRITE
);
355 * write_page - Write one page to given swap location.
356 * @buf: Address we're writing.
357 * @offset: Offset of the swap page we're writing to.
358 * @hb: bio completion batch
361 static int write_page(void *buf
, sector_t offset
, struct hib_bio_batch
*hb
)
370 src
= (void *)__get_free_page(__GFP_RECLAIM
| __GFP_NOWARN
|
375 ret
= hib_wait_io(hb
); /* Free pages */
378 src
= (void *)__get_free_page(__GFP_RECLAIM
|
385 hb
= NULL
; /* Go synchronous */
392 return hib_submit_io(WRITE_SYNC
, offset
, src
, hb
);
395 static void release_swap_writer(struct swap_map_handle
*handle
)
398 free_page((unsigned long)handle
->cur
);
402 static int get_swap_writer(struct swap_map_handle
*handle
)
406 ret
= swsusp_swap_check();
409 printk(KERN_ERR
"PM: Cannot find swap device, try "
413 handle
->cur
= (struct swap_map_page
*)get_zeroed_page(GFP_KERNEL
);
418 handle
->cur_swap
= alloc_swapdev_block(root_swap
);
419 if (!handle
->cur_swap
) {
424 handle
->reqd_free_pages
= reqd_free_pages();
425 handle
->first_sector
= handle
->cur_swap
;
428 release_swap_writer(handle
);
430 swsusp_close(FMODE_WRITE
);
434 static int swap_write_page(struct swap_map_handle
*handle
, void *buf
,
435 struct hib_bio_batch
*hb
)
442 offset
= alloc_swapdev_block(root_swap
);
443 error
= write_page(buf
, offset
, hb
);
446 handle
->cur
->entries
[handle
->k
++] = offset
;
447 if (handle
->k
>= MAP_PAGE_ENTRIES
) {
448 offset
= alloc_swapdev_block(root_swap
);
451 handle
->cur
->next_swap
= offset
;
452 error
= write_page(handle
->cur
, handle
->cur_swap
, hb
);
455 clear_page(handle
->cur
);
456 handle
->cur_swap
= offset
;
459 if (hb
&& low_free_pages() <= handle
->reqd_free_pages
) {
460 error
= hib_wait_io(hb
);
464 * Recalculate the number of required free pages, to
465 * make sure we never take more than half.
467 handle
->reqd_free_pages
= reqd_free_pages();
474 static int flush_swap_writer(struct swap_map_handle
*handle
)
476 if (handle
->cur
&& handle
->cur_swap
)
477 return write_page(handle
->cur
, handle
->cur_swap
, NULL
);
482 static int swap_writer_finish(struct swap_map_handle
*handle
,
483 unsigned int flags
, int error
)
486 flush_swap_writer(handle
);
487 printk(KERN_INFO
"PM: S");
488 error
= mark_swapfiles(handle
, flags
);
493 free_all_swap_pages(root_swap
);
494 release_swap_writer(handle
);
495 swsusp_close(FMODE_WRITE
);
500 /* We need to remember how much compressed data we need to read. */
501 #define LZO_HEADER sizeof(size_t)
503 /* Number of pages/bytes we'll compress at one time. */
504 #define LZO_UNC_PAGES 32
505 #define LZO_UNC_SIZE (LZO_UNC_PAGES * PAGE_SIZE)
507 /* Number of pages/bytes we need for compressed data (worst case). */
508 #define LZO_CMP_PAGES DIV_ROUND_UP(lzo1x_worst_compress(LZO_UNC_SIZE) + \
509 LZO_HEADER, PAGE_SIZE)
510 #define LZO_CMP_SIZE (LZO_CMP_PAGES * PAGE_SIZE)
512 /* Maximum number of threads for compression/decompression. */
513 #define LZO_THREADS 3
515 /* Minimum/maximum number of pages for read buffering. */
516 #define LZO_MIN_RD_PAGES 1024
517 #define LZO_MAX_RD_PAGES 8192
521 * save_image - save the suspend image data
524 static int save_image(struct swap_map_handle
*handle
,
525 struct snapshot_handle
*snapshot
,
526 unsigned int nr_to_write
)
532 struct hib_bio_batch hb
;
538 printk(KERN_INFO
"PM: Saving image data pages (%u pages)...\n",
540 m
= nr_to_write
/ 10;
546 ret
= snapshot_read_next(snapshot
);
549 ret
= swap_write_page(handle
, data_of(*snapshot
), &hb
);
553 printk(KERN_INFO
"PM: Image saving progress: %3d%%\n",
557 err2
= hib_wait_io(&hb
);
562 printk(KERN_INFO
"PM: Image saving done.\n");
563 swsusp_show_speed(start
, stop
, nr_to_write
, "Wrote");
568 * Structure used for CRC32.
571 struct task_struct
*thr
; /* thread */
572 atomic_t ready
; /* ready to start flag */
573 atomic_t stop
; /* ready to stop flag */
574 unsigned run_threads
; /* nr current threads */
575 wait_queue_head_t go
; /* start crc update */
576 wait_queue_head_t done
; /* crc update done */
577 u32
*crc32
; /* points to handle's crc32 */
578 size_t *unc_len
[LZO_THREADS
]; /* uncompressed lengths */
579 unsigned char *unc
[LZO_THREADS
]; /* uncompressed data */
583 * CRC32 update function that runs in its own thread.
585 static int crc32_threadfn(void *data
)
587 struct crc_data
*d
= data
;
591 wait_event(d
->go
, atomic_read(&d
->ready
) ||
592 kthread_should_stop());
593 if (kthread_should_stop()) {
595 atomic_set(&d
->stop
, 1);
599 atomic_set(&d
->ready
, 0);
601 for (i
= 0; i
< d
->run_threads
; i
++)
602 *d
->crc32
= crc32_le(*d
->crc32
,
603 d
->unc
[i
], *d
->unc_len
[i
]);
604 atomic_set(&d
->stop
, 1);
610 * Structure used for LZO data compression.
613 struct task_struct
*thr
; /* thread */
614 atomic_t ready
; /* ready to start flag */
615 atomic_t stop
; /* ready to stop flag */
616 int ret
; /* return code */
617 wait_queue_head_t go
; /* start compression */
618 wait_queue_head_t done
; /* compression done */
619 size_t unc_len
; /* uncompressed length */
620 size_t cmp_len
; /* compressed length */
621 unsigned char unc
[LZO_UNC_SIZE
]; /* uncompressed buffer */
622 unsigned char cmp
[LZO_CMP_SIZE
]; /* compressed buffer */
623 unsigned char wrk
[LZO1X_1_MEM_COMPRESS
]; /* compression workspace */
627 * Compression function that runs in its own thread.
629 static int lzo_compress_threadfn(void *data
)
631 struct cmp_data
*d
= data
;
634 wait_event(d
->go
, atomic_read(&d
->ready
) ||
635 kthread_should_stop());
636 if (kthread_should_stop()) {
639 atomic_set(&d
->stop
, 1);
643 atomic_set(&d
->ready
, 0);
645 d
->ret
= lzo1x_1_compress(d
->unc
, d
->unc_len
,
646 d
->cmp
+ LZO_HEADER
, &d
->cmp_len
,
648 atomic_set(&d
->stop
, 1);
655 * save_image_lzo - Save the suspend image data compressed with LZO.
656 * @handle: Swap map handle to use for saving the image.
657 * @snapshot: Image to read data from.
658 * @nr_to_write: Number of pages to save.
660 static int save_image_lzo(struct swap_map_handle
*handle
,
661 struct snapshot_handle
*snapshot
,
662 unsigned int nr_to_write
)
668 struct hib_bio_batch hb
;
672 unsigned thr
, run_threads
, nr_threads
;
673 unsigned char *page
= NULL
;
674 struct cmp_data
*data
= NULL
;
675 struct crc_data
*crc
= NULL
;
680 * We'll limit the number of threads for compression to limit memory
683 nr_threads
= num_online_cpus() - 1;
684 nr_threads
= clamp_val(nr_threads
, 1, LZO_THREADS
);
686 page
= (void *)__get_free_page(__GFP_RECLAIM
| __GFP_HIGH
);
688 printk(KERN_ERR
"PM: Failed to allocate LZO page\n");
693 data
= vmalloc(sizeof(*data
) * nr_threads
);
695 printk(KERN_ERR
"PM: Failed to allocate LZO data\n");
699 for (thr
= 0; thr
< nr_threads
; thr
++)
700 memset(&data
[thr
], 0, offsetof(struct cmp_data
, go
));
702 crc
= kmalloc(sizeof(*crc
), GFP_KERNEL
);
704 printk(KERN_ERR
"PM: Failed to allocate crc\n");
708 memset(crc
, 0, offsetof(struct crc_data
, go
));
711 * Start the compression threads.
713 for (thr
= 0; thr
< nr_threads
; thr
++) {
714 init_waitqueue_head(&data
[thr
].go
);
715 init_waitqueue_head(&data
[thr
].done
);
717 data
[thr
].thr
= kthread_run(lzo_compress_threadfn
,
719 "image_compress/%u", thr
);
720 if (IS_ERR(data
[thr
].thr
)) {
721 data
[thr
].thr
= NULL
;
723 "PM: Cannot start compression threads\n");
730 * Start the CRC32 thread.
732 init_waitqueue_head(&crc
->go
);
733 init_waitqueue_head(&crc
->done
);
736 crc
->crc32
= &handle
->crc32
;
737 for (thr
= 0; thr
< nr_threads
; thr
++) {
738 crc
->unc
[thr
] = data
[thr
].unc
;
739 crc
->unc_len
[thr
] = &data
[thr
].unc_len
;
742 crc
->thr
= kthread_run(crc32_threadfn
, crc
, "image_crc32");
743 if (IS_ERR(crc
->thr
)) {
745 printk(KERN_ERR
"PM: Cannot start CRC32 thread\n");
751 * Adjust the number of required free pages after all allocations have
752 * been done. We don't want to run out of pages when writing.
754 handle
->reqd_free_pages
= reqd_free_pages();
757 "PM: Using %u thread(s) for compression.\n"
758 "PM: Compressing and saving image data (%u pages)...\n",
759 nr_threads
, nr_to_write
);
760 m
= nr_to_write
/ 10;
766 for (thr
= 0; thr
< nr_threads
; thr
++) {
767 for (off
= 0; off
< LZO_UNC_SIZE
; off
+= PAGE_SIZE
) {
768 ret
= snapshot_read_next(snapshot
);
775 memcpy(data
[thr
].unc
+ off
,
776 data_of(*snapshot
), PAGE_SIZE
);
780 "PM: Image saving progress: "
788 data
[thr
].unc_len
= off
;
790 atomic_set(&data
[thr
].ready
, 1);
791 wake_up(&data
[thr
].go
);
797 crc
->run_threads
= thr
;
798 atomic_set(&crc
->ready
, 1);
801 for (run_threads
= thr
, thr
= 0; thr
< run_threads
; thr
++) {
802 wait_event(data
[thr
].done
,
803 atomic_read(&data
[thr
].stop
));
804 atomic_set(&data
[thr
].stop
, 0);
809 printk(KERN_ERR
"PM: LZO compression failed\n");
813 if (unlikely(!data
[thr
].cmp_len
||
815 lzo1x_worst_compress(data
[thr
].unc_len
))) {
817 "PM: Invalid LZO compressed length\n");
822 *(size_t *)data
[thr
].cmp
= data
[thr
].cmp_len
;
825 * Given we are writing one page at a time to disk, we
826 * copy that much from the buffer, although the last
827 * bit will likely be smaller than full page. This is
828 * OK - we saved the length of the compressed data, so
829 * any garbage at the end will be discarded when we
833 off
< LZO_HEADER
+ data
[thr
].cmp_len
;
835 memcpy(page
, data
[thr
].cmp
+ off
, PAGE_SIZE
);
837 ret
= swap_write_page(handle
, page
, &hb
);
843 wait_event(crc
->done
, atomic_read(&crc
->stop
));
844 atomic_set(&crc
->stop
, 0);
848 err2
= hib_wait_io(&hb
);
853 printk(KERN_INFO
"PM: Image saving done.\n");
854 swsusp_show_speed(start
, stop
, nr_to_write
, "Wrote");
858 kthread_stop(crc
->thr
);
862 for (thr
= 0; thr
< nr_threads
; thr
++)
864 kthread_stop(data
[thr
].thr
);
867 if (page
) free_page((unsigned long)page
);
873 * enough_swap - Make sure we have enough swap to save the image.
875 * Returns TRUE or FALSE after checking the total amount of swap
876 * space avaiable from the resume partition.
879 static int enough_swap(unsigned int nr_pages
, unsigned int flags
)
881 unsigned int free_swap
= count_swap_pages(root_swap
, 1);
882 unsigned int required
;
884 pr_debug("PM: Free swap pages: %u\n", free_swap
);
886 required
= PAGES_FOR_IO
+ nr_pages
;
887 return free_swap
> required
;
891 * swsusp_write - Write entire image and metadata.
892 * @flags: flags to pass to the "boot" kernel in the image header
894 * It is important _NOT_ to umount filesystems at this point. We want
895 * them synced (in case something goes wrong) but we DO not want to mark
896 * filesystem clean: it is not. (And it does not matter, if we resume
897 * correctly, we'll mark system clean, anyway.)
900 int swsusp_write(unsigned int flags
)
902 struct swap_map_handle handle
;
903 struct snapshot_handle snapshot
;
904 struct swsusp_info
*header
;
908 pages
= snapshot_get_image_size();
909 error
= get_swap_writer(&handle
);
911 printk(KERN_ERR
"PM: Cannot get swap writer\n");
914 if (flags
& SF_NOCOMPRESS_MODE
) {
915 if (!enough_swap(pages
, flags
)) {
916 printk(KERN_ERR
"PM: Not enough free swap\n");
921 memset(&snapshot
, 0, sizeof(struct snapshot_handle
));
922 error
= snapshot_read_next(&snapshot
);
923 if (error
< PAGE_SIZE
) {
929 header
= (struct swsusp_info
*)data_of(snapshot
);
930 error
= swap_write_page(&handle
, header
, NULL
);
932 error
= (flags
& SF_NOCOMPRESS_MODE
) ?
933 save_image(&handle
, &snapshot
, pages
- 1) :
934 save_image_lzo(&handle
, &snapshot
, pages
- 1);
937 error
= swap_writer_finish(&handle
, flags
, error
);
942 * The following functions allow us to read data using a swap map
943 * in a file-alike way
946 static void release_swap_reader(struct swap_map_handle
*handle
)
948 struct swap_map_page_list
*tmp
;
950 while (handle
->maps
) {
951 if (handle
->maps
->map
)
952 free_page((unsigned long)handle
->maps
->map
);
954 handle
->maps
= handle
->maps
->next
;
960 static int get_swap_reader(struct swap_map_handle
*handle
,
961 unsigned int *flags_p
)
964 struct swap_map_page_list
*tmp
, *last
;
967 *flags_p
= swsusp_header
->flags
;
969 if (!swsusp_header
->image
) /* how can this happen? */
973 last
= handle
->maps
= NULL
;
974 offset
= swsusp_header
->image
;
976 tmp
= kmalloc(sizeof(*handle
->maps
), GFP_KERNEL
);
978 release_swap_reader(handle
);
981 memset(tmp
, 0, sizeof(*tmp
));
988 tmp
->map
= (struct swap_map_page
*)
989 __get_free_page(__GFP_RECLAIM
| __GFP_HIGH
);
991 release_swap_reader(handle
);
995 error
= hib_submit_io(READ_SYNC
, offset
, tmp
->map
, NULL
);
997 release_swap_reader(handle
);
1000 offset
= tmp
->map
->next_swap
;
1003 handle
->cur
= handle
->maps
->map
;
1007 static int swap_read_page(struct swap_map_handle
*handle
, void *buf
,
1008 struct hib_bio_batch
*hb
)
1012 struct swap_map_page_list
*tmp
;
1016 offset
= handle
->cur
->entries
[handle
->k
];
1019 error
= hib_submit_io(READ_SYNC
, offset
, buf
, hb
);
1022 if (++handle
->k
>= MAP_PAGE_ENTRIES
) {
1024 free_page((unsigned long)handle
->maps
->map
);
1026 handle
->maps
= handle
->maps
->next
;
1029 release_swap_reader(handle
);
1031 handle
->cur
= handle
->maps
->map
;
1036 static int swap_reader_finish(struct swap_map_handle
*handle
)
1038 release_swap_reader(handle
);
1044 * load_image - load the image using the swap map handle
1045 * @handle and the snapshot handle @snapshot
1046 * (assume there are @nr_pages pages to load)
1049 static int load_image(struct swap_map_handle
*handle
,
1050 struct snapshot_handle
*snapshot
,
1051 unsigned int nr_to_read
)
1057 struct hib_bio_batch hb
;
1061 hib_init_batch(&hb
);
1063 clean_pages_on_read
= true;
1064 printk(KERN_INFO
"PM: Loading image data pages (%u pages)...\n",
1066 m
= nr_to_read
/ 10;
1070 start
= ktime_get();
1072 ret
= snapshot_write_next(snapshot
);
1075 ret
= swap_read_page(handle
, data_of(*snapshot
), &hb
);
1078 if (snapshot
->sync_read
)
1079 ret
= hib_wait_io(&hb
);
1082 if (!(nr_pages
% m
))
1083 printk(KERN_INFO
"PM: Image loading progress: %3d%%\n",
1087 err2
= hib_wait_io(&hb
);
1092 printk(KERN_INFO
"PM: Image loading done.\n");
1093 snapshot_write_finalize(snapshot
);
1094 if (!snapshot_image_loaded(snapshot
))
1097 swsusp_show_speed(start
, stop
, nr_to_read
, "Read");
1102 * Structure used for LZO data decompression.
1105 struct task_struct
*thr
; /* thread */
1106 atomic_t ready
; /* ready to start flag */
1107 atomic_t stop
; /* ready to stop flag */
1108 int ret
; /* return code */
1109 wait_queue_head_t go
; /* start decompression */
1110 wait_queue_head_t done
; /* decompression done */
1111 size_t unc_len
; /* uncompressed length */
1112 size_t cmp_len
; /* compressed length */
1113 unsigned char unc
[LZO_UNC_SIZE
]; /* uncompressed buffer */
1114 unsigned char cmp
[LZO_CMP_SIZE
]; /* compressed buffer */
1118 * Deompression function that runs in its own thread.
1120 static int lzo_decompress_threadfn(void *data
)
1122 struct dec_data
*d
= data
;
1125 wait_event(d
->go
, atomic_read(&d
->ready
) ||
1126 kthread_should_stop());
1127 if (kthread_should_stop()) {
1130 atomic_set(&d
->stop
, 1);
1134 atomic_set(&d
->ready
, 0);
1136 d
->unc_len
= LZO_UNC_SIZE
;
1137 d
->ret
= lzo1x_decompress_safe(d
->cmp
+ LZO_HEADER
, d
->cmp_len
,
1138 d
->unc
, &d
->unc_len
);
1139 if (clean_pages_on_decompress
)
1140 flush_icache_range((unsigned long)d
->unc
,
1141 (unsigned long)d
->unc
+ d
->unc_len
);
1143 atomic_set(&d
->stop
, 1);
1150 * load_image_lzo - Load compressed image data and decompress them with LZO.
1151 * @handle: Swap map handle to use for loading data.
1152 * @snapshot: Image to copy uncompressed data into.
1153 * @nr_to_read: Number of pages to load.
1155 static int load_image_lzo(struct swap_map_handle
*handle
,
1156 struct snapshot_handle
*snapshot
,
1157 unsigned int nr_to_read
)
1162 struct hib_bio_batch hb
;
1167 unsigned i
, thr
, run_threads
, nr_threads
;
1168 unsigned ring
= 0, pg
= 0, ring_size
= 0,
1169 have
= 0, want
, need
, asked
= 0;
1170 unsigned long read_pages
= 0;
1171 unsigned char **page
= NULL
;
1172 struct dec_data
*data
= NULL
;
1173 struct crc_data
*crc
= NULL
;
1175 hib_init_batch(&hb
);
1178 * We'll limit the number of threads for decompression to limit memory
1181 nr_threads
= num_online_cpus() - 1;
1182 nr_threads
= clamp_val(nr_threads
, 1, LZO_THREADS
);
1184 page
= vmalloc(sizeof(*page
) * LZO_MAX_RD_PAGES
);
1186 printk(KERN_ERR
"PM: Failed to allocate LZO page\n");
1191 data
= vmalloc(sizeof(*data
) * nr_threads
);
1193 printk(KERN_ERR
"PM: Failed to allocate LZO data\n");
1197 for (thr
= 0; thr
< nr_threads
; thr
++)
1198 memset(&data
[thr
], 0, offsetof(struct dec_data
, go
));
1200 crc
= kmalloc(sizeof(*crc
), GFP_KERNEL
);
1202 printk(KERN_ERR
"PM: Failed to allocate crc\n");
1206 memset(crc
, 0, offsetof(struct crc_data
, go
));
1208 clean_pages_on_decompress
= true;
1211 * Start the decompression threads.
1213 for (thr
= 0; thr
< nr_threads
; thr
++) {
1214 init_waitqueue_head(&data
[thr
].go
);
1215 init_waitqueue_head(&data
[thr
].done
);
1217 data
[thr
].thr
= kthread_run(lzo_decompress_threadfn
,
1219 "image_decompress/%u", thr
);
1220 if (IS_ERR(data
[thr
].thr
)) {
1221 data
[thr
].thr
= NULL
;
1223 "PM: Cannot start decompression threads\n");
1230 * Start the CRC32 thread.
1232 init_waitqueue_head(&crc
->go
);
1233 init_waitqueue_head(&crc
->done
);
1236 crc
->crc32
= &handle
->crc32
;
1237 for (thr
= 0; thr
< nr_threads
; thr
++) {
1238 crc
->unc
[thr
] = data
[thr
].unc
;
1239 crc
->unc_len
[thr
] = &data
[thr
].unc_len
;
1242 crc
->thr
= kthread_run(crc32_threadfn
, crc
, "image_crc32");
1243 if (IS_ERR(crc
->thr
)) {
1245 printk(KERN_ERR
"PM: Cannot start CRC32 thread\n");
1251 * Set the number of pages for read buffering.
1252 * This is complete guesswork, because we'll only know the real
1253 * picture once prepare_image() is called, which is much later on
1254 * during the image load phase. We'll assume the worst case and
1255 * say that none of the image pages are from high memory.
1257 if (low_free_pages() > snapshot_get_image_size())
1258 read_pages
= (low_free_pages() - snapshot_get_image_size()) / 2;
1259 read_pages
= clamp_val(read_pages
, LZO_MIN_RD_PAGES
, LZO_MAX_RD_PAGES
);
1261 for (i
= 0; i
< read_pages
; i
++) {
1262 page
[i
] = (void *)__get_free_page(i
< LZO_CMP_PAGES
?
1263 __GFP_RECLAIM
| __GFP_HIGH
:
1264 __GFP_RECLAIM
| __GFP_NOWARN
|
1268 if (i
< LZO_CMP_PAGES
) {
1271 "PM: Failed to allocate LZO pages\n");
1279 want
= ring_size
= i
;
1282 "PM: Using %u thread(s) for decompression.\n"
1283 "PM: Loading and decompressing image data (%u pages)...\n",
1284 nr_threads
, nr_to_read
);
1285 m
= nr_to_read
/ 10;
1289 start
= ktime_get();
1291 ret
= snapshot_write_next(snapshot
);
1296 for (i
= 0; !eof
&& i
< want
; i
++) {
1297 ret
= swap_read_page(handle
, page
[ring
], &hb
);
1300 * On real read error, finish. On end of data,
1301 * set EOF flag and just exit the read loop.
1304 handle
->cur
->entries
[handle
->k
]) {
1311 if (++ring
>= ring_size
)
1318 * We are out of data, wait for some more.
1324 ret
= hib_wait_io(&hb
);
1333 if (crc
->run_threads
) {
1334 wait_event(crc
->done
, atomic_read(&crc
->stop
));
1335 atomic_set(&crc
->stop
, 0);
1336 crc
->run_threads
= 0;
1339 for (thr
= 0; have
&& thr
< nr_threads
; thr
++) {
1340 data
[thr
].cmp_len
= *(size_t *)page
[pg
];
1341 if (unlikely(!data
[thr
].cmp_len
||
1343 lzo1x_worst_compress(LZO_UNC_SIZE
))) {
1345 "PM: Invalid LZO compressed length\n");
1350 need
= DIV_ROUND_UP(data
[thr
].cmp_len
+ LZO_HEADER
,
1361 off
< LZO_HEADER
+ data
[thr
].cmp_len
;
1363 memcpy(data
[thr
].cmp
+ off
,
1364 page
[pg
], PAGE_SIZE
);
1367 if (++pg
>= ring_size
)
1371 atomic_set(&data
[thr
].ready
, 1);
1372 wake_up(&data
[thr
].go
);
1376 * Wait for more data while we are decompressing.
1378 if (have
< LZO_CMP_PAGES
&& asked
) {
1379 ret
= hib_wait_io(&hb
);
1388 for (run_threads
= thr
, thr
= 0; thr
< run_threads
; thr
++) {
1389 wait_event(data
[thr
].done
,
1390 atomic_read(&data
[thr
].stop
));
1391 atomic_set(&data
[thr
].stop
, 0);
1393 ret
= data
[thr
].ret
;
1397 "PM: LZO decompression failed\n");
1401 if (unlikely(!data
[thr
].unc_len
||
1402 data
[thr
].unc_len
> LZO_UNC_SIZE
||
1403 data
[thr
].unc_len
& (PAGE_SIZE
- 1))) {
1405 "PM: Invalid LZO uncompressed length\n");
1411 off
< data
[thr
].unc_len
; off
+= PAGE_SIZE
) {
1412 memcpy(data_of(*snapshot
),
1413 data
[thr
].unc
+ off
, PAGE_SIZE
);
1415 if (!(nr_pages
% m
))
1417 "PM: Image loading progress: "
1422 ret
= snapshot_write_next(snapshot
);
1424 crc
->run_threads
= thr
+ 1;
1425 atomic_set(&crc
->ready
, 1);
1432 crc
->run_threads
= thr
;
1433 atomic_set(&crc
->ready
, 1);
1438 if (crc
->run_threads
) {
1439 wait_event(crc
->done
, atomic_read(&crc
->stop
));
1440 atomic_set(&crc
->stop
, 0);
1444 printk(KERN_INFO
"PM: Image loading done.\n");
1445 snapshot_write_finalize(snapshot
);
1446 if (!snapshot_image_loaded(snapshot
))
1449 if (swsusp_header
->flags
& SF_CRC32_MODE
) {
1450 if(handle
->crc32
!= swsusp_header
->crc32
) {
1452 "PM: Invalid image CRC32!\n");
1458 swsusp_show_speed(start
, stop
, nr_to_read
, "Read");
1460 for (i
= 0; i
< ring_size
; i
++)
1461 free_page((unsigned long)page
[i
]);
1464 kthread_stop(crc
->thr
);
1468 for (thr
= 0; thr
< nr_threads
; thr
++)
1470 kthread_stop(data
[thr
].thr
);
1479 * swsusp_read - read the hibernation image.
1480 * @flags_p: flags passed by the "frozen" kernel in the image header should
1481 * be written into this memory location
1484 int swsusp_read(unsigned int *flags_p
)
1487 struct swap_map_handle handle
;
1488 struct snapshot_handle snapshot
;
1489 struct swsusp_info
*header
;
1491 memset(&snapshot
, 0, sizeof(struct snapshot_handle
));
1492 error
= snapshot_write_next(&snapshot
);
1493 if (error
< PAGE_SIZE
)
1494 return error
< 0 ? error
: -EFAULT
;
1495 header
= (struct swsusp_info
*)data_of(snapshot
);
1496 error
= get_swap_reader(&handle
, flags_p
);
1500 error
= swap_read_page(&handle
, header
, NULL
);
1502 error
= (*flags_p
& SF_NOCOMPRESS_MODE
) ?
1503 load_image(&handle
, &snapshot
, header
->pages
- 1) :
1504 load_image_lzo(&handle
, &snapshot
, header
->pages
- 1);
1506 swap_reader_finish(&handle
);
1509 pr_debug("PM: Image successfully loaded\n");
1511 pr_debug("PM: Error %d resuming\n", error
);
1516 * swsusp_check - Check for swsusp signature in the resume device
1519 int swsusp_check(void)
1523 hib_resume_bdev
= blkdev_get_by_dev(swsusp_resume_device
,
1525 if (!IS_ERR(hib_resume_bdev
)) {
1526 set_blocksize(hib_resume_bdev
, PAGE_SIZE
);
1527 clear_page(swsusp_header
);
1528 error
= hib_submit_io(READ_SYNC
, swsusp_resume_block
,
1529 swsusp_header
, NULL
);
1533 if (!memcmp(HIBERNATE_SIG
, swsusp_header
->sig
, 10)) {
1534 memcpy(swsusp_header
->sig
, swsusp_header
->orig_sig
, 10);
1535 /* Reset swap signature now */
1536 error
= hib_submit_io(WRITE_SYNC
, swsusp_resume_block
,
1537 swsusp_header
, NULL
);
1544 blkdev_put(hib_resume_bdev
, FMODE_READ
);
1546 pr_debug("PM: Image signature found, resuming\n");
1548 error
= PTR_ERR(hib_resume_bdev
);
1552 pr_debug("PM: Image not found (code %d)\n", error
);
1558 * swsusp_close - close swap device.
1561 void swsusp_close(fmode_t mode
)
1563 if (IS_ERR(hib_resume_bdev
)) {
1564 pr_debug("PM: Image device not initialised\n");
1568 blkdev_put(hib_resume_bdev
, mode
);
1572 * swsusp_unmark - Unmark swsusp signature in the resume device
1575 #ifdef CONFIG_SUSPEND
1576 int swsusp_unmark(void)
1580 hib_submit_io(READ_SYNC
, swsusp_resume_block
, swsusp_header
, NULL
);
1581 if (!memcmp(HIBERNATE_SIG
,swsusp_header
->sig
, 10)) {
1582 memcpy(swsusp_header
->sig
,swsusp_header
->orig_sig
, 10);
1583 error
= hib_submit_io(WRITE_SYNC
, swsusp_resume_block
,
1584 swsusp_header
, NULL
);
1586 printk(KERN_ERR
"PM: Cannot find swsusp signature!\n");
1591 * We just returned from suspend, we don't need the image any more.
1593 free_all_swap_pages(root_swap
);
1599 static int swsusp_header_init(void)
1601 swsusp_header
= (struct swsusp_header
*) __get_free_page(GFP_KERNEL
);
1603 panic("Could not allocate memory for swsusp_header\n");
1607 core_initcall(swsusp_header_init
);