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1/*
2 * linux/kernel/power/swap.c
3 *
4 * This file provides functions for reading the suspend image from
5 * and writing it to a swap partition.
6 *
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>
10 *
11 * This file is released under the GPLv2.
12 *
13 */
14
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>
25#include <linux/pm.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>
34
35#include "power.h"
36
37#define HIBERNATE_SIG "S1SUSPEND"
38
39/*
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.
45 *
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.
49 *
50 * During resume we pick up all swap_map_page structures into a list.
51 */
52
53#define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(sector_t) - 1)
54
55/*
56 * Number of free pages that are not high.
57 */
58static inline unsigned long low_free_pages(void)
59{
60 return nr_free_pages() - nr_free_highpages();
61}
62
63/*
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.
66 */
67static inline unsigned long reqd_free_pages(void)
68{
69 return low_free_pages() / 2;
70}
71
72struct swap_map_page {
73 sector_t entries[MAP_PAGE_ENTRIES];
74 sector_t next_swap;
75};
76
77struct swap_map_page_list {
78 struct swap_map_page *map;
79 struct swap_map_page_list *next;
80};
81
82/**
83 * The swap_map_handle structure is used for handling swap in
84 * a file-alike way
85 */
86
87struct swap_map_handle {
88 struct swap_map_page *cur;
89 struct swap_map_page_list *maps;
90 sector_t cur_swap;
91 sector_t first_sector;
92 unsigned int k;
93 unsigned long reqd_free_pages;
94 u32 crc32;
95};
96
97struct swsusp_header {
98 char reserved[PAGE_SIZE - 20 - sizeof(sector_t) - sizeof(int) -
99 sizeof(u32)];
100 u32 crc32;
101 sector_t image;
102 unsigned int flags; /* Flags to pass to the "boot" kernel */
103 char orig_sig[10];
104 char sig[10];
105} __packed;
106
107static struct swsusp_header *swsusp_header;
108
109/**
110 * The following functions are used for tracing the allocated
111 * swap pages, so that they can be freed in case of an error.
112 */
113
114struct swsusp_extent {
115 struct rb_node node;
116 unsigned long start;
117 unsigned long end;
118};
119
120static struct rb_root swsusp_extents = RB_ROOT;
121
122static int swsusp_extents_insert(unsigned long swap_offset)
123{
124 struct rb_node **new = &(swsusp_extents.rb_node);
125 struct rb_node *parent = NULL;
126 struct swsusp_extent *ext;
127
128 /* Figure out where to put the new node */
129 while (*new) {
130 ext = rb_entry(*new, struct swsusp_extent, node);
131 parent = *new;
132 if (swap_offset < ext->start) {
133 /* Try to merge */
134 if (swap_offset == ext->start - 1) {
135 ext->start--;
136 return 0;
137 }
138 new = &((*new)->rb_left);
139 } else if (swap_offset > ext->end) {
140 /* Try to merge */
141 if (swap_offset == ext->end + 1) {
142 ext->end++;
143 return 0;
144 }
145 new = &((*new)->rb_right);
146 } else {
147 /* It already is in the tree */
148 return -EINVAL;
149 }
150 }
151 /* Add the new node and rebalance the tree. */
152 ext = kzalloc(sizeof(struct swsusp_extent), GFP_KERNEL);
153 if (!ext)
154 return -ENOMEM;
155
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);
160 return 0;
161}
162
163/**
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.
166 */
167
168sector_t alloc_swapdev_block(int swap)
169{
170 unsigned long offset;
171
172 offset = swp_offset(get_swap_page_of_type(swap));
173 if (offset) {
174 if (swsusp_extents_insert(offset))
175 swap_free(swp_entry(swap, offset));
176 else
177 return swapdev_block(swap, offset);
178 }
179 return 0;
180}
181
182/**
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
185 * allocated.
186 */
187
188void free_all_swap_pages(int swap)
189{
190 struct rb_node *node;
191
192 while ((node = swsusp_extents.rb_node)) {
193 struct swsusp_extent *ext;
194 unsigned long offset;
195
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));
200
201 kfree(ext);
202 }
203}
204
205int swsusp_swap_in_use(void)
206{
207 return (swsusp_extents.rb_node != NULL);
208}
209
210/*
211 * General things
212 */
213
214static unsigned short root_swap = 0xffff;
215static struct block_device *hib_resume_bdev;
216
217struct hib_bio_batch {
218 atomic_t count;
219 wait_queue_head_t wait;
220 int error;
221};
222
223static void hib_init_batch(struct hib_bio_batch *hb)
224{
225 atomic_set(&hb->count, 0);
226 init_waitqueue_head(&hb->wait);
227 hb->error = 0;
228}
229
230static void hib_end_io(struct bio *bio)
231{
232 struct hib_bio_batch *hb = bio->bi_private;
233 struct page *page = bio->bi_io_vec[0].bv_page;
234
235 if (bio->bi_error) {
236 printk(KERN_ALERT "Read-error on swap-device (%u:%u:%Lu)\n",
237 imajor(bio->bi_bdev->bd_inode),
238 iminor(bio->bi_bdev->bd_inode),
239 (unsigned long long)bio->bi_iter.bi_sector);
240 }
241
242 if (bio_data_dir(bio) == WRITE)
243 put_page(page);
244
245 if (bio->bi_error && !hb->error)
246 hb->error = bio->bi_error;
247 if (atomic_dec_and_test(&hb->count))
248 wake_up(&hb->wait);
249
250 bio_put(bio);
251}
252
253static int hib_submit_io(int rw, pgoff_t page_off, void *addr,
254 struct hib_bio_batch *hb)
255{
256 struct page *page = virt_to_page(addr);
257 struct bio *bio;
258 int error = 0;
259
260 bio = bio_alloc(__GFP_RECLAIM | __GFP_HIGH, 1);
261 bio->bi_iter.bi_sector = page_off * (PAGE_SIZE >> 9);
262 bio->bi_bdev = hib_resume_bdev;
263
264 if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
265 printk(KERN_ERR "PM: Adding page to bio failed at %llu\n",
266 (unsigned long long)bio->bi_iter.bi_sector);
267 bio_put(bio);
268 return -EFAULT;
269 }
270
271 if (hb) {
272 bio->bi_end_io = hib_end_io;
273 bio->bi_private = hb;
274 atomic_inc(&hb->count);
275 submit_bio(rw, bio);
276 } else {
277 error = submit_bio_wait(rw, bio);
278 bio_put(bio);
279 }
280
281 return error;
282}
283
284static int hib_wait_io(struct hib_bio_batch *hb)
285{
286 wait_event(hb->wait, atomic_read(&hb->count) == 0);
287 return hb->error;
288}
289
290/*
291 * Saving part
292 */
293
294static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
295{
296 int error;
297
298 hib_submit_io(READ_SYNC, swsusp_resume_block, swsusp_header, NULL);
299 if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||
300 !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {
301 memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);
302 memcpy(swsusp_header->sig, HIBERNATE_SIG, 10);
303 swsusp_header->image = handle->first_sector;
304 swsusp_header->flags = flags;
305 if (flags & SF_CRC32_MODE)
306 swsusp_header->crc32 = handle->crc32;
307 error = hib_submit_io(WRITE_SYNC, swsusp_resume_block,
308 swsusp_header, NULL);
309 } else {
310 printk(KERN_ERR "PM: Swap header not found!\n");
311 error = -ENODEV;
312 }
313 return error;
314}
315
316/**
317 * swsusp_swap_check - check if the resume device is a swap device
318 * and get its index (if so)
319 *
320 * This is called before saving image
321 */
322static int swsusp_swap_check(void)
323{
324 int res;
325
326 res = swap_type_of(swsusp_resume_device, swsusp_resume_block,
327 &hib_resume_bdev);
328 if (res < 0)
329 return res;
330
331 root_swap = res;
332 res = blkdev_get(hib_resume_bdev, FMODE_WRITE, NULL);
333 if (res)
334 return res;
335
336 res = set_blocksize(hib_resume_bdev, PAGE_SIZE);
337 if (res < 0)
338 blkdev_put(hib_resume_bdev, FMODE_WRITE);
339
340 return res;
341}
342
343/**
344 * write_page - Write one page to given swap location.
345 * @buf: Address we're writing.
346 * @offset: Offset of the swap page we're writing to.
347 * @hb: bio completion batch
348 */
349
350static int write_page(void *buf, sector_t offset, struct hib_bio_batch *hb)
351{
352 void *src;
353 int ret;
354
355 if (!offset)
356 return -ENOSPC;
357
358 if (hb) {
359 src = (void *)__get_free_page(__GFP_RECLAIM | __GFP_NOWARN |
360 __GFP_NORETRY);
361 if (src) {
362 copy_page(src, buf);
363 } else {
364 ret = hib_wait_io(hb); /* Free pages */
365 if (ret)
366 return ret;
367 src = (void *)__get_free_page(__GFP_RECLAIM |
368 __GFP_NOWARN |
369 __GFP_NORETRY);
370 if (src) {
371 copy_page(src, buf);
372 } else {
373 WARN_ON_ONCE(1);
374 hb = NULL; /* Go synchronous */
375 src = buf;
376 }
377 }
378 } else {
379 src = buf;
380 }
381 return hib_submit_io(WRITE_SYNC, offset, src, hb);
382}
383
384static void release_swap_writer(struct swap_map_handle *handle)
385{
386 if (handle->cur)
387 free_page((unsigned long)handle->cur);
388 handle->cur = NULL;
389}
390
391static int get_swap_writer(struct swap_map_handle *handle)
392{
393 int ret;
394
395 ret = swsusp_swap_check();
396 if (ret) {
397 if (ret != -ENOSPC)
398 printk(KERN_ERR "PM: Cannot find swap device, try "
399 "swapon -a.\n");
400 return ret;
401 }
402 handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL);
403 if (!handle->cur) {
404 ret = -ENOMEM;
405 goto err_close;
406 }
407 handle->cur_swap = alloc_swapdev_block(root_swap);
408 if (!handle->cur_swap) {
409 ret = -ENOSPC;
410 goto err_rel;
411 }
412 handle->k = 0;
413 handle->reqd_free_pages = reqd_free_pages();
414 handle->first_sector = handle->cur_swap;
415 return 0;
416err_rel:
417 release_swap_writer(handle);
418err_close:
419 swsusp_close(FMODE_WRITE);
420 return ret;
421}
422
423static int swap_write_page(struct swap_map_handle *handle, void *buf,
424 struct hib_bio_batch *hb)
425{
426 int error = 0;
427 sector_t offset;
428
429 if (!handle->cur)
430 return -EINVAL;
431 offset = alloc_swapdev_block(root_swap);
432 error = write_page(buf, offset, hb);
433 if (error)
434 return error;
435 handle->cur->entries[handle->k++] = offset;
436 if (handle->k >= MAP_PAGE_ENTRIES) {
437 offset = alloc_swapdev_block(root_swap);
438 if (!offset)
439 return -ENOSPC;
440 handle->cur->next_swap = offset;
441 error = write_page(handle->cur, handle->cur_swap, hb);
442 if (error)
443 goto out;
444 clear_page(handle->cur);
445 handle->cur_swap = offset;
446 handle->k = 0;
447
448 if (hb && low_free_pages() <= handle->reqd_free_pages) {
449 error = hib_wait_io(hb);
450 if (error)
451 goto out;
452 /*
453 * Recalculate the number of required free pages, to
454 * make sure we never take more than half.
455 */
456 handle->reqd_free_pages = reqd_free_pages();
457 }
458 }
459 out:
460 return error;
461}
462
463static int flush_swap_writer(struct swap_map_handle *handle)
464{
465 if (handle->cur && handle->cur_swap)
466 return write_page(handle->cur, handle->cur_swap, NULL);
467 else
468 return -EINVAL;
469}
470
471static int swap_writer_finish(struct swap_map_handle *handle,
472 unsigned int flags, int error)
473{
474 if (!error) {
475 flush_swap_writer(handle);
476 printk(KERN_INFO "PM: S");
477 error = mark_swapfiles(handle, flags);
478 printk("|\n");
479 }
480
481 if (error)
482 free_all_swap_pages(root_swap);
483 release_swap_writer(handle);
484 swsusp_close(FMODE_WRITE);
485
486 return error;
487}
488
489/* We need to remember how much compressed data we need to read. */
490#define LZO_HEADER sizeof(size_t)
491
492/* Number of pages/bytes we'll compress at one time. */
493#define LZO_UNC_PAGES 32
494#define LZO_UNC_SIZE (LZO_UNC_PAGES * PAGE_SIZE)
495
496/* Number of pages/bytes we need for compressed data (worst case). */
497#define LZO_CMP_PAGES DIV_ROUND_UP(lzo1x_worst_compress(LZO_UNC_SIZE) + \
498 LZO_HEADER, PAGE_SIZE)
499#define LZO_CMP_SIZE (LZO_CMP_PAGES * PAGE_SIZE)
500
501/* Maximum number of threads for compression/decompression. */
502#define LZO_THREADS 3
503
504/* Minimum/maximum number of pages for read buffering. */
505#define LZO_MIN_RD_PAGES 1024
506#define LZO_MAX_RD_PAGES 8192
507
508
509/**
510 * save_image - save the suspend image data
511 */
512
513static int save_image(struct swap_map_handle *handle,
514 struct snapshot_handle *snapshot,
515 unsigned int nr_to_write)
516{
517 unsigned int m;
518 int ret;
519 int nr_pages;
520 int err2;
521 struct hib_bio_batch hb;
522 ktime_t start;
523 ktime_t stop;
524
525 hib_init_batch(&hb);
526
527 printk(KERN_INFO "PM: Saving image data pages (%u pages)...\n",
528 nr_to_write);
529 m = nr_to_write / 10;
530 if (!m)
531 m = 1;
532 nr_pages = 0;
533 start = ktime_get();
534 while (1) {
535 ret = snapshot_read_next(snapshot);
536 if (ret <= 0)
537 break;
538 ret = swap_write_page(handle, data_of(*snapshot), &hb);
539 if (ret)
540 break;
541 if (!(nr_pages % m))
542 printk(KERN_INFO "PM: Image saving progress: %3d%%\n",
543 nr_pages / m * 10);
544 nr_pages++;
545 }
546 err2 = hib_wait_io(&hb);
547 stop = ktime_get();
548 if (!ret)
549 ret = err2;
550 if (!ret)
551 printk(KERN_INFO "PM: Image saving done.\n");
552 swsusp_show_speed(start, stop, nr_to_write, "Wrote");
553 return ret;
554}
555
556/**
557 * Structure used for CRC32.
558 */
559struct crc_data {
560 struct task_struct *thr; /* thread */
561 atomic_t ready; /* ready to start flag */
562 atomic_t stop; /* ready to stop flag */
563 unsigned run_threads; /* nr current threads */
564 wait_queue_head_t go; /* start crc update */
565 wait_queue_head_t done; /* crc update done */
566 u32 *crc32; /* points to handle's crc32 */
567 size_t *unc_len[LZO_THREADS]; /* uncompressed lengths */
568 unsigned char *unc[LZO_THREADS]; /* uncompressed data */
569};
570
571/**
572 * CRC32 update function that runs in its own thread.
573 */
574static int crc32_threadfn(void *data)
575{
576 struct crc_data *d = data;
577 unsigned i;
578
579 while (1) {
580 wait_event(d->go, atomic_read(&d->ready) ||
581 kthread_should_stop());
582 if (kthread_should_stop()) {
583 d->thr = NULL;
584 atomic_set(&d->stop, 1);
585 wake_up(&d->done);
586 break;
587 }
588 atomic_set(&d->ready, 0);
589
590 for (i = 0; i < d->run_threads; i++)
591 *d->crc32 = crc32_le(*d->crc32,
592 d->unc[i], *d->unc_len[i]);
593 atomic_set(&d->stop, 1);
594 wake_up(&d->done);
595 }
596 return 0;
597}
598/**
599 * Structure used for LZO data compression.
600 */
601struct cmp_data {
602 struct task_struct *thr; /* thread */
603 atomic_t ready; /* ready to start flag */
604 atomic_t stop; /* ready to stop flag */
605 int ret; /* return code */
606 wait_queue_head_t go; /* start compression */
607 wait_queue_head_t done; /* compression done */
608 size_t unc_len; /* uncompressed length */
609 size_t cmp_len; /* compressed length */
610 unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */
611 unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */
612 unsigned char wrk[LZO1X_1_MEM_COMPRESS]; /* compression workspace */
613};
614
615/**
616 * Compression function that runs in its own thread.
617 */
618static int lzo_compress_threadfn(void *data)
619{
620 struct cmp_data *d = data;
621
622 while (1) {
623 wait_event(d->go, atomic_read(&d->ready) ||
624 kthread_should_stop());
625 if (kthread_should_stop()) {
626 d->thr = NULL;
627 d->ret = -1;
628 atomic_set(&d->stop, 1);
629 wake_up(&d->done);
630 break;
631 }
632 atomic_set(&d->ready, 0);
633
634 d->ret = lzo1x_1_compress(d->unc, d->unc_len,
635 d->cmp + LZO_HEADER, &d->cmp_len,
636 d->wrk);
637 atomic_set(&d->stop, 1);
638 wake_up(&d->done);
639 }
640 return 0;
641}
642
643/**
644 * save_image_lzo - Save the suspend image data compressed with LZO.
645 * @handle: Swap map handle to use for saving the image.
646 * @snapshot: Image to read data from.
647 * @nr_to_write: Number of pages to save.
648 */
649static int save_image_lzo(struct swap_map_handle *handle,
650 struct snapshot_handle *snapshot,
651 unsigned int nr_to_write)
652{
653 unsigned int m;
654 int ret = 0;
655 int nr_pages;
656 int err2;
657 struct hib_bio_batch hb;
658 ktime_t start;
659 ktime_t stop;
660 size_t off;
661 unsigned thr, run_threads, nr_threads;
662 unsigned char *page = NULL;
663 struct cmp_data *data = NULL;
664 struct crc_data *crc = NULL;
665
666 hib_init_batch(&hb);
667
668 /*
669 * We'll limit the number of threads for compression to limit memory
670 * footprint.
671 */
672 nr_threads = num_online_cpus() - 1;
673 nr_threads = clamp_val(nr_threads, 1, LZO_THREADS);
674
675 page = (void *)__get_free_page(__GFP_RECLAIM | __GFP_HIGH);
676 if (!page) {
677 printk(KERN_ERR "PM: Failed to allocate LZO page\n");
678 ret = -ENOMEM;
679 goto out_clean;
680 }
681
682 data = vmalloc(sizeof(*data) * nr_threads);
683 if (!data) {
684 printk(KERN_ERR "PM: Failed to allocate LZO data\n");
685 ret = -ENOMEM;
686 goto out_clean;
687 }
688 for (thr = 0; thr < nr_threads; thr++)
689 memset(&data[thr], 0, offsetof(struct cmp_data, go));
690
691 crc = kmalloc(sizeof(*crc), GFP_KERNEL);
692 if (!crc) {
693 printk(KERN_ERR "PM: Failed to allocate crc\n");
694 ret = -ENOMEM;
695 goto out_clean;
696 }
697 memset(crc, 0, offsetof(struct crc_data, go));
698
699 /*
700 * Start the compression threads.
701 */
702 for (thr = 0; thr < nr_threads; thr++) {
703 init_waitqueue_head(&data[thr].go);
704 init_waitqueue_head(&data[thr].done);
705
706 data[thr].thr = kthread_run(lzo_compress_threadfn,
707 &data[thr],
708 "image_compress/%u", thr);
709 if (IS_ERR(data[thr].thr)) {
710 data[thr].thr = NULL;
711 printk(KERN_ERR
712 "PM: Cannot start compression threads\n");
713 ret = -ENOMEM;
714 goto out_clean;
715 }
716 }
717
718 /*
719 * Start the CRC32 thread.
720 */
721 init_waitqueue_head(&crc->go);
722 init_waitqueue_head(&crc->done);
723
724 handle->crc32 = 0;
725 crc->crc32 = &handle->crc32;
726 for (thr = 0; thr < nr_threads; thr++) {
727 crc->unc[thr] = data[thr].unc;
728 crc->unc_len[thr] = &data[thr].unc_len;
729 }
730
731 crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
732 if (IS_ERR(crc->thr)) {
733 crc->thr = NULL;
734 printk(KERN_ERR "PM: Cannot start CRC32 thread\n");
735 ret = -ENOMEM;
736 goto out_clean;
737 }
738
739 /*
740 * Adjust the number of required free pages after all allocations have
741 * been done. We don't want to run out of pages when writing.
742 */
743 handle->reqd_free_pages = reqd_free_pages();
744
745 printk(KERN_INFO
746 "PM: Using %u thread(s) for compression.\n"
747 "PM: Compressing and saving image data (%u pages)...\n",
748 nr_threads, nr_to_write);
749 m = nr_to_write / 10;
750 if (!m)
751 m = 1;
752 nr_pages = 0;
753 start = ktime_get();
754 for (;;) {
755 for (thr = 0; thr < nr_threads; thr++) {
756 for (off = 0; off < LZO_UNC_SIZE; off += PAGE_SIZE) {
757 ret = snapshot_read_next(snapshot);
758 if (ret < 0)
759 goto out_finish;
760
761 if (!ret)
762 break;
763
764 memcpy(data[thr].unc + off,
765 data_of(*snapshot), PAGE_SIZE);
766
767 if (!(nr_pages % m))
768 printk(KERN_INFO
769 "PM: Image saving progress: "
770 "%3d%%\n",
771 nr_pages / m * 10);
772 nr_pages++;
773 }
774 if (!off)
775 break;
776
777 data[thr].unc_len = off;
778
779 atomic_set(&data[thr].ready, 1);
780 wake_up(&data[thr].go);
781 }
782
783 if (!thr)
784 break;
785
786 crc->run_threads = thr;
787 atomic_set(&crc->ready, 1);
788 wake_up(&crc->go);
789
790 for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
791 wait_event(data[thr].done,
792 atomic_read(&data[thr].stop));
793 atomic_set(&data[thr].stop, 0);
794
795 ret = data[thr].ret;
796
797 if (ret < 0) {
798 printk(KERN_ERR "PM: LZO compression failed\n");
799 goto out_finish;
800 }
801
802 if (unlikely(!data[thr].cmp_len ||
803 data[thr].cmp_len >
804 lzo1x_worst_compress(data[thr].unc_len))) {
805 printk(KERN_ERR
806 "PM: Invalid LZO compressed length\n");
807 ret = -1;
808 goto out_finish;
809 }
810
811 *(size_t *)data[thr].cmp = data[thr].cmp_len;
812
813 /*
814 * Given we are writing one page at a time to disk, we
815 * copy that much from the buffer, although the last
816 * bit will likely be smaller than full page. This is
817 * OK - we saved the length of the compressed data, so
818 * any garbage at the end will be discarded when we
819 * read it.
820 */
821 for (off = 0;
822 off < LZO_HEADER + data[thr].cmp_len;
823 off += PAGE_SIZE) {
824 memcpy(page, data[thr].cmp + off, PAGE_SIZE);
825
826 ret = swap_write_page(handle, page, &hb);
827 if (ret)
828 goto out_finish;
829 }
830 }
831
832 wait_event(crc->done, atomic_read(&crc->stop));
833 atomic_set(&crc->stop, 0);
834 }
835
836out_finish:
837 err2 = hib_wait_io(&hb);
838 stop = ktime_get();
839 if (!ret)
840 ret = err2;
841 if (!ret)
842 printk(KERN_INFO "PM: Image saving done.\n");
843 swsusp_show_speed(start, stop, nr_to_write, "Wrote");
844out_clean:
845 if (crc) {
846 if (crc->thr)
847 kthread_stop(crc->thr);
848 kfree(crc);
849 }
850 if (data) {
851 for (thr = 0; thr < nr_threads; thr++)
852 if (data[thr].thr)
853 kthread_stop(data[thr].thr);
854 vfree(data);
855 }
856 if (page) free_page((unsigned long)page);
857
858 return ret;
859}
860
861/**
862 * enough_swap - Make sure we have enough swap to save the image.
863 *
864 * Returns TRUE or FALSE after checking the total amount of swap
865 * space avaiable from the resume partition.
866 */
867
868static int enough_swap(unsigned int nr_pages, unsigned int flags)
869{
870 unsigned int free_swap = count_swap_pages(root_swap, 1);
871 unsigned int required;
872
873 pr_debug("PM: Free swap pages: %u\n", free_swap);
874
875 required = PAGES_FOR_IO + nr_pages;
876 return free_swap > required;
877}
878
879/**
880 * swsusp_write - Write entire image and metadata.
881 * @flags: flags to pass to the "boot" kernel in the image header
882 *
883 * It is important _NOT_ to umount filesystems at this point. We want
884 * them synced (in case something goes wrong) but we DO not want to mark
885 * filesystem clean: it is not. (And it does not matter, if we resume
886 * correctly, we'll mark system clean, anyway.)
887 */
888
889int swsusp_write(unsigned int flags)
890{
891 struct swap_map_handle handle;
892 struct snapshot_handle snapshot;
893 struct swsusp_info *header;
894 unsigned long pages;
895 int error;
896
897 pages = snapshot_get_image_size();
898 error = get_swap_writer(&handle);
899 if (error) {
900 printk(KERN_ERR "PM: Cannot get swap writer\n");
901 return error;
902 }
903 if (flags & SF_NOCOMPRESS_MODE) {
904 if (!enough_swap(pages, flags)) {
905 printk(KERN_ERR "PM: Not enough free swap\n");
906 error = -ENOSPC;
907 goto out_finish;
908 }
909 }
910 memset(&snapshot, 0, sizeof(struct snapshot_handle));
911 error = snapshot_read_next(&snapshot);
912 if (error < PAGE_SIZE) {
913 if (error >= 0)
914 error = -EFAULT;
915
916 goto out_finish;
917 }
918 header = (struct swsusp_info *)data_of(snapshot);
919 error = swap_write_page(&handle, header, NULL);
920 if (!error) {
921 error = (flags & SF_NOCOMPRESS_MODE) ?
922 save_image(&handle, &snapshot, pages - 1) :
923 save_image_lzo(&handle, &snapshot, pages - 1);
924 }
925out_finish:
926 error = swap_writer_finish(&handle, flags, error);
927 return error;
928}
929
930/**
931 * The following functions allow us to read data using a swap map
932 * in a file-alike way
933 */
934
935static void release_swap_reader(struct swap_map_handle *handle)
936{
937 struct swap_map_page_list *tmp;
938
939 while (handle->maps) {
940 if (handle->maps->map)
941 free_page((unsigned long)handle->maps->map);
942 tmp = handle->maps;
943 handle->maps = handle->maps->next;
944 kfree(tmp);
945 }
946 handle->cur = NULL;
947}
948
949static int get_swap_reader(struct swap_map_handle *handle,
950 unsigned int *flags_p)
951{
952 int error;
953 struct swap_map_page_list *tmp, *last;
954 sector_t offset;
955
956 *flags_p = swsusp_header->flags;
957
958 if (!swsusp_header->image) /* how can this happen? */
959 return -EINVAL;
960
961 handle->cur = NULL;
962 last = handle->maps = NULL;
963 offset = swsusp_header->image;
964 while (offset) {
965 tmp = kmalloc(sizeof(*handle->maps), GFP_KERNEL);
966 if (!tmp) {
967 release_swap_reader(handle);
968 return -ENOMEM;
969 }
970 memset(tmp, 0, sizeof(*tmp));
971 if (!handle->maps)
972 handle->maps = tmp;
973 if (last)
974 last->next = tmp;
975 last = tmp;
976
977 tmp->map = (struct swap_map_page *)
978 __get_free_page(__GFP_RECLAIM | __GFP_HIGH);
979 if (!tmp->map) {
980 release_swap_reader(handle);
981 return -ENOMEM;
982 }
983
984 error = hib_submit_io(READ_SYNC, offset, tmp->map, NULL);
985 if (error) {
986 release_swap_reader(handle);
987 return error;
988 }
989 offset = tmp->map->next_swap;
990 }
991 handle->k = 0;
992 handle->cur = handle->maps->map;
993 return 0;
994}
995
996static int swap_read_page(struct swap_map_handle *handle, void *buf,
997 struct hib_bio_batch *hb)
998{
999 sector_t offset;
1000 int error;
1001 struct swap_map_page_list *tmp;
1002
1003 if (!handle->cur)
1004 return -EINVAL;
1005 offset = handle->cur->entries[handle->k];
1006 if (!offset)
1007 return -EFAULT;
1008 error = hib_submit_io(READ_SYNC, offset, buf, hb);
1009 if (error)
1010 return error;
1011 if (++handle->k >= MAP_PAGE_ENTRIES) {
1012 handle->k = 0;
1013 free_page((unsigned long)handle->maps->map);
1014 tmp = handle->maps;
1015 handle->maps = handle->maps->next;
1016 kfree(tmp);
1017 if (!handle->maps)
1018 release_swap_reader(handle);
1019 else
1020 handle->cur = handle->maps->map;
1021 }
1022 return error;
1023}
1024
1025static int swap_reader_finish(struct swap_map_handle *handle)
1026{
1027 release_swap_reader(handle);
1028
1029 return 0;
1030}
1031
1032/**
1033 * load_image - load the image using the swap map handle
1034 * @handle and the snapshot handle @snapshot
1035 * (assume there are @nr_pages pages to load)
1036 */
1037
1038static int load_image(struct swap_map_handle *handle,
1039 struct snapshot_handle *snapshot,
1040 unsigned int nr_to_read)
1041{
1042 unsigned int m;
1043 int ret = 0;
1044 ktime_t start;
1045 ktime_t stop;
1046 struct hib_bio_batch hb;
1047 int err2;
1048 unsigned nr_pages;
1049
1050 hib_init_batch(&hb);
1051
1052 printk(KERN_INFO "PM: Loading image data pages (%u pages)...\n",
1053 nr_to_read);
1054 m = nr_to_read / 10;
1055 if (!m)
1056 m = 1;
1057 nr_pages = 0;
1058 start = ktime_get();
1059 for ( ; ; ) {
1060 ret = snapshot_write_next(snapshot);
1061 if (ret <= 0)
1062 break;
1063 ret = swap_read_page(handle, data_of(*snapshot), &hb);
1064 if (ret)
1065 break;
1066 if (snapshot->sync_read)
1067 ret = hib_wait_io(&hb);
1068 if (ret)
1069 break;
1070 if (!(nr_pages % m))
1071 printk(KERN_INFO "PM: Image loading progress: %3d%%\n",
1072 nr_pages / m * 10);
1073 nr_pages++;
1074 }
1075 err2 = hib_wait_io(&hb);
1076 stop = ktime_get();
1077 if (!ret)
1078 ret = err2;
1079 if (!ret) {
1080 printk(KERN_INFO "PM: Image loading done.\n");
1081 snapshot_write_finalize(snapshot);
1082 if (!snapshot_image_loaded(snapshot))
1083 ret = -ENODATA;
1084 }
1085 swsusp_show_speed(start, stop, nr_to_read, "Read");
1086 return ret;
1087}
1088
1089/**
1090 * Structure used for LZO data decompression.
1091 */
1092struct dec_data {
1093 struct task_struct *thr; /* thread */
1094 atomic_t ready; /* ready to start flag */
1095 atomic_t stop; /* ready to stop flag */
1096 int ret; /* return code */
1097 wait_queue_head_t go; /* start decompression */
1098 wait_queue_head_t done; /* decompression done */
1099 size_t unc_len; /* uncompressed length */
1100 size_t cmp_len; /* compressed length */
1101 unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */
1102 unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */
1103};
1104
1105/**
1106 * Deompression function that runs in its own thread.
1107 */
1108static int lzo_decompress_threadfn(void *data)
1109{
1110 struct dec_data *d = data;
1111
1112 while (1) {
1113 wait_event(d->go, atomic_read(&d->ready) ||
1114 kthread_should_stop());
1115 if (kthread_should_stop()) {
1116 d->thr = NULL;
1117 d->ret = -1;
1118 atomic_set(&d->stop, 1);
1119 wake_up(&d->done);
1120 break;
1121 }
1122 atomic_set(&d->ready, 0);
1123
1124 d->unc_len = LZO_UNC_SIZE;
1125 d->ret = lzo1x_decompress_safe(d->cmp + LZO_HEADER, d->cmp_len,
1126 d->unc, &d->unc_len);
1127 atomic_set(&d->stop, 1);
1128 wake_up(&d->done);
1129 }
1130 return 0;
1131}
1132
1133/**
1134 * load_image_lzo - Load compressed image data and decompress them with LZO.
1135 * @handle: Swap map handle to use for loading data.
1136 * @snapshot: Image to copy uncompressed data into.
1137 * @nr_to_read: Number of pages to load.
1138 */
1139static int load_image_lzo(struct swap_map_handle *handle,
1140 struct snapshot_handle *snapshot,
1141 unsigned int nr_to_read)
1142{
1143 unsigned int m;
1144 int ret = 0;
1145 int eof = 0;
1146 struct hib_bio_batch hb;
1147 ktime_t start;
1148 ktime_t stop;
1149 unsigned nr_pages;
1150 size_t off;
1151 unsigned i, thr, run_threads, nr_threads;
1152 unsigned ring = 0, pg = 0, ring_size = 0,
1153 have = 0, want, need, asked = 0;
1154 unsigned long read_pages = 0;
1155 unsigned char **page = NULL;
1156 struct dec_data *data = NULL;
1157 struct crc_data *crc = NULL;
1158
1159 hib_init_batch(&hb);
1160
1161 /*
1162 * We'll limit the number of threads for decompression to limit memory
1163 * footprint.
1164 */
1165 nr_threads = num_online_cpus() - 1;
1166 nr_threads = clamp_val(nr_threads, 1, LZO_THREADS);
1167
1168 page = vmalloc(sizeof(*page) * LZO_MAX_RD_PAGES);
1169 if (!page) {
1170 printk(KERN_ERR "PM: Failed to allocate LZO page\n");
1171 ret = -ENOMEM;
1172 goto out_clean;
1173 }
1174
1175 data = vmalloc(sizeof(*data) * nr_threads);
1176 if (!data) {
1177 printk(KERN_ERR "PM: Failed to allocate LZO data\n");
1178 ret = -ENOMEM;
1179 goto out_clean;
1180 }
1181 for (thr = 0; thr < nr_threads; thr++)
1182 memset(&data[thr], 0, offsetof(struct dec_data, go));
1183
1184 crc = kmalloc(sizeof(*crc), GFP_KERNEL);
1185 if (!crc) {
1186 printk(KERN_ERR "PM: Failed to allocate crc\n");
1187 ret = -ENOMEM;
1188 goto out_clean;
1189 }
1190 memset(crc, 0, offsetof(struct crc_data, go));
1191
1192 /*
1193 * Start the decompression threads.
1194 */
1195 for (thr = 0; thr < nr_threads; thr++) {
1196 init_waitqueue_head(&data[thr].go);
1197 init_waitqueue_head(&data[thr].done);
1198
1199 data[thr].thr = kthread_run(lzo_decompress_threadfn,
1200 &data[thr],
1201 "image_decompress/%u", thr);
1202 if (IS_ERR(data[thr].thr)) {
1203 data[thr].thr = NULL;
1204 printk(KERN_ERR
1205 "PM: Cannot start decompression threads\n");
1206 ret = -ENOMEM;
1207 goto out_clean;
1208 }
1209 }
1210
1211 /*
1212 * Start the CRC32 thread.
1213 */
1214 init_waitqueue_head(&crc->go);
1215 init_waitqueue_head(&crc->done);
1216
1217 handle->crc32 = 0;
1218 crc->crc32 = &handle->crc32;
1219 for (thr = 0; thr < nr_threads; thr++) {
1220 crc->unc[thr] = data[thr].unc;
1221 crc->unc_len[thr] = &data[thr].unc_len;
1222 }
1223
1224 crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
1225 if (IS_ERR(crc->thr)) {
1226 crc->thr = NULL;
1227 printk(KERN_ERR "PM: Cannot start CRC32 thread\n");
1228 ret = -ENOMEM;
1229 goto out_clean;
1230 }
1231
1232 /*
1233 * Set the number of pages for read buffering.
1234 * This is complete guesswork, because we'll only know the real
1235 * picture once prepare_image() is called, which is much later on
1236 * during the image load phase. We'll assume the worst case and
1237 * say that none of the image pages are from high memory.
1238 */
1239 if (low_free_pages() > snapshot_get_image_size())
1240 read_pages = (low_free_pages() - snapshot_get_image_size()) / 2;
1241 read_pages = clamp_val(read_pages, LZO_MIN_RD_PAGES, LZO_MAX_RD_PAGES);
1242
1243 for (i = 0; i < read_pages; i++) {
1244 page[i] = (void *)__get_free_page(i < LZO_CMP_PAGES ?
1245 __GFP_RECLAIM | __GFP_HIGH :
1246 __GFP_RECLAIM | __GFP_NOWARN |
1247 __GFP_NORETRY);
1248
1249 if (!page[i]) {
1250 if (i < LZO_CMP_PAGES) {
1251 ring_size = i;
1252 printk(KERN_ERR
1253 "PM: Failed to allocate LZO pages\n");
1254 ret = -ENOMEM;
1255 goto out_clean;
1256 } else {
1257 break;
1258 }
1259 }
1260 }
1261 want = ring_size = i;
1262
1263 printk(KERN_INFO
1264 "PM: Using %u thread(s) for decompression.\n"
1265 "PM: Loading and decompressing image data (%u pages)...\n",
1266 nr_threads, nr_to_read);
1267 m = nr_to_read / 10;
1268 if (!m)
1269 m = 1;
1270 nr_pages = 0;
1271 start = ktime_get();
1272
1273 ret = snapshot_write_next(snapshot);
1274 if (ret <= 0)
1275 goto out_finish;
1276
1277 for(;;) {
1278 for (i = 0; !eof && i < want; i++) {
1279 ret = swap_read_page(handle, page[ring], &hb);
1280 if (ret) {
1281 /*
1282 * On real read error, finish. On end of data,
1283 * set EOF flag and just exit the read loop.
1284 */
1285 if (handle->cur &&
1286 handle->cur->entries[handle->k]) {
1287 goto out_finish;
1288 } else {
1289 eof = 1;
1290 break;
1291 }
1292 }
1293 if (++ring >= ring_size)
1294 ring = 0;
1295 }
1296 asked += i;
1297 want -= i;
1298
1299 /*
1300 * We are out of data, wait for some more.
1301 */
1302 if (!have) {
1303 if (!asked)
1304 break;
1305
1306 ret = hib_wait_io(&hb);
1307 if (ret)
1308 goto out_finish;
1309 have += asked;
1310 asked = 0;
1311 if (eof)
1312 eof = 2;
1313 }
1314
1315 if (crc->run_threads) {
1316 wait_event(crc->done, atomic_read(&crc->stop));
1317 atomic_set(&crc->stop, 0);
1318 crc->run_threads = 0;
1319 }
1320
1321 for (thr = 0; have && thr < nr_threads; thr++) {
1322 data[thr].cmp_len = *(size_t *)page[pg];
1323 if (unlikely(!data[thr].cmp_len ||
1324 data[thr].cmp_len >
1325 lzo1x_worst_compress(LZO_UNC_SIZE))) {
1326 printk(KERN_ERR
1327 "PM: Invalid LZO compressed length\n");
1328 ret = -1;
1329 goto out_finish;
1330 }
1331
1332 need = DIV_ROUND_UP(data[thr].cmp_len + LZO_HEADER,
1333 PAGE_SIZE);
1334 if (need > have) {
1335 if (eof > 1) {
1336 ret = -1;
1337 goto out_finish;
1338 }
1339 break;
1340 }
1341
1342 for (off = 0;
1343 off < LZO_HEADER + data[thr].cmp_len;
1344 off += PAGE_SIZE) {
1345 memcpy(data[thr].cmp + off,
1346 page[pg], PAGE_SIZE);
1347 have--;
1348 want++;
1349 if (++pg >= ring_size)
1350 pg = 0;
1351 }
1352
1353 atomic_set(&data[thr].ready, 1);
1354 wake_up(&data[thr].go);
1355 }
1356
1357 /*
1358 * Wait for more data while we are decompressing.
1359 */
1360 if (have < LZO_CMP_PAGES && asked) {
1361 ret = hib_wait_io(&hb);
1362 if (ret)
1363 goto out_finish;
1364 have += asked;
1365 asked = 0;
1366 if (eof)
1367 eof = 2;
1368 }
1369
1370 for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
1371 wait_event(data[thr].done,
1372 atomic_read(&data[thr].stop));
1373 atomic_set(&data[thr].stop, 0);
1374
1375 ret = data[thr].ret;
1376
1377 if (ret < 0) {
1378 printk(KERN_ERR
1379 "PM: LZO decompression failed\n");
1380 goto out_finish;
1381 }
1382
1383 if (unlikely(!data[thr].unc_len ||
1384 data[thr].unc_len > LZO_UNC_SIZE ||
1385 data[thr].unc_len & (PAGE_SIZE - 1))) {
1386 printk(KERN_ERR
1387 "PM: Invalid LZO uncompressed length\n");
1388 ret = -1;
1389 goto out_finish;
1390 }
1391
1392 for (off = 0;
1393 off < data[thr].unc_len; off += PAGE_SIZE) {
1394 memcpy(data_of(*snapshot),
1395 data[thr].unc + off, PAGE_SIZE);
1396
1397 if (!(nr_pages % m))
1398 printk(KERN_INFO
1399 "PM: Image loading progress: "
1400 "%3d%%\n",
1401 nr_pages / m * 10);
1402 nr_pages++;
1403
1404 ret = snapshot_write_next(snapshot);
1405 if (ret <= 0) {
1406 crc->run_threads = thr + 1;
1407 atomic_set(&crc->ready, 1);
1408 wake_up(&crc->go);
1409 goto out_finish;
1410 }
1411 }
1412 }
1413
1414 crc->run_threads = thr;
1415 atomic_set(&crc->ready, 1);
1416 wake_up(&crc->go);
1417 }
1418
1419out_finish:
1420 if (crc->run_threads) {
1421 wait_event(crc->done, atomic_read(&crc->stop));
1422 atomic_set(&crc->stop, 0);
1423 }
1424 stop = ktime_get();
1425 if (!ret) {
1426 printk(KERN_INFO "PM: Image loading done.\n");
1427 snapshot_write_finalize(snapshot);
1428 if (!snapshot_image_loaded(snapshot))
1429 ret = -ENODATA;
1430 if (!ret) {
1431 if (swsusp_header->flags & SF_CRC32_MODE) {
1432 if(handle->crc32 != swsusp_header->crc32) {
1433 printk(KERN_ERR
1434 "PM: Invalid image CRC32!\n");
1435 ret = -ENODATA;
1436 }
1437 }
1438 }
1439 }
1440 swsusp_show_speed(start, stop, nr_to_read, "Read");
1441out_clean:
1442 for (i = 0; i < ring_size; i++)
1443 free_page((unsigned long)page[i]);
1444 if (crc) {
1445 if (crc->thr)
1446 kthread_stop(crc->thr);
1447 kfree(crc);
1448 }
1449 if (data) {
1450 for (thr = 0; thr < nr_threads; thr++)
1451 if (data[thr].thr)
1452 kthread_stop(data[thr].thr);
1453 vfree(data);
1454 }
1455 vfree(page);
1456
1457 return ret;
1458}
1459
1460/**
1461 * swsusp_read - read the hibernation image.
1462 * @flags_p: flags passed by the "frozen" kernel in the image header should
1463 * be written into this memory location
1464 */
1465
1466int swsusp_read(unsigned int *flags_p)
1467{
1468 int error;
1469 struct swap_map_handle handle;
1470 struct snapshot_handle snapshot;
1471 struct swsusp_info *header;
1472
1473 memset(&snapshot, 0, sizeof(struct snapshot_handle));
1474 error = snapshot_write_next(&snapshot);
1475 if (error < PAGE_SIZE)
1476 return error < 0 ? error : -EFAULT;
1477 header = (struct swsusp_info *)data_of(snapshot);
1478 error = get_swap_reader(&handle, flags_p);
1479 if (error)
1480 goto end;
1481 if (!error)
1482 error = swap_read_page(&handle, header, NULL);
1483 if (!error) {
1484 error = (*flags_p & SF_NOCOMPRESS_MODE) ?
1485 load_image(&handle, &snapshot, header->pages - 1) :
1486 load_image_lzo(&handle, &snapshot, header->pages - 1);
1487 }
1488 swap_reader_finish(&handle);
1489end:
1490 if (!error)
1491 pr_debug("PM: Image successfully loaded\n");
1492 else
1493 pr_debug("PM: Error %d resuming\n", error);
1494 return error;
1495}
1496
1497/**
1498 * swsusp_check - Check for swsusp signature in the resume device
1499 */
1500
1501int swsusp_check(void)
1502{
1503 int error;
1504
1505 hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device,
1506 FMODE_READ, NULL);
1507 if (!IS_ERR(hib_resume_bdev)) {
1508 set_blocksize(hib_resume_bdev, PAGE_SIZE);
1509 clear_page(swsusp_header);
1510 error = hib_submit_io(READ_SYNC, swsusp_resume_block,
1511 swsusp_header, NULL);
1512 if (error)
1513 goto put;
1514
1515 if (!memcmp(HIBERNATE_SIG, swsusp_header->sig, 10)) {
1516 memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10);
1517 /* Reset swap signature now */
1518 error = hib_submit_io(WRITE_SYNC, swsusp_resume_block,
1519 swsusp_header, NULL);
1520 } else {
1521 error = -EINVAL;
1522 }
1523
1524put:
1525 if (error)
1526 blkdev_put(hib_resume_bdev, FMODE_READ);
1527 else
1528 pr_debug("PM: Image signature found, resuming\n");
1529 } else {
1530 error = PTR_ERR(hib_resume_bdev);
1531 }
1532
1533 if (error)
1534 pr_debug("PM: Image not found (code %d)\n", error);
1535
1536 return error;
1537}
1538
1539/**
1540 * swsusp_close - close swap device.
1541 */
1542
1543void swsusp_close(fmode_t mode)
1544{
1545 if (IS_ERR(hib_resume_bdev)) {
1546 pr_debug("PM: Image device not initialised\n");
1547 return;
1548 }
1549
1550 blkdev_put(hib_resume_bdev, mode);
1551}
1552
1553/**
1554 * swsusp_unmark - Unmark swsusp signature in the resume device
1555 */
1556
1557#ifdef CONFIG_SUSPEND
1558int swsusp_unmark(void)
1559{
1560 int error;
1561
1562 hib_submit_io(READ_SYNC, swsusp_resume_block, swsusp_header, NULL);
1563 if (!memcmp(HIBERNATE_SIG,swsusp_header->sig, 10)) {
1564 memcpy(swsusp_header->sig,swsusp_header->orig_sig, 10);
1565 error = hib_submit_io(WRITE_SYNC, swsusp_resume_block,
1566 swsusp_header, NULL);
1567 } else {
1568 printk(KERN_ERR "PM: Cannot find swsusp signature!\n");
1569 error = -ENODEV;
1570 }
1571
1572 /*
1573 * We just returned from suspend, we don't need the image any more.
1574 */
1575 free_all_swap_pages(root_swap);
1576
1577 return error;
1578}
1579#endif
1580
1581static int swsusp_header_init(void)
1582{
1583 swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);
1584 if (!swsusp_header)
1585 panic("Could not allocate memory for swsusp_header\n");
1586 return 0;
1587}
1588
1589core_initcall(swsusp_header_init);
1/*
2 * linux/kernel/power/swap.c
3 *
4 * This file provides functions for reading the suspend image from
5 * and writing it to a swap partition.
6 *
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 Bojan Smojver <bojan@rexursive.com>
10 *
11 * This file is released under the GPLv2.
12 *
13 */
14
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>
26#include <linux/pm.h>
27#include <linux/slab.h>
28#include <linux/lzo.h>
29#include <linux/vmalloc.h>
30
31#include "power.h"
32
33#define HIBERNATE_SIG "S1SUSPEND"
34
35/*
36 * The swap map is a data structure used for keeping track of each page
37 * written to a swap partition. It consists of many swap_map_page
38 * structures that contain each an array of MAP_PAGE_ENTRIES swap entries.
39 * These structures are stored on the swap and linked together with the
40 * help of the .next_swap member.
41 *
42 * The swap map is created during suspend. The swap map pages are
43 * allocated and populated one at a time, so we only need one memory
44 * page to set up the entire structure.
45 *
46 * During resume we also only need to use one swap_map_page structure
47 * at a time.
48 */
49
50#define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(sector_t) - 1)
51
52struct swap_map_page {
53 sector_t entries[MAP_PAGE_ENTRIES];
54 sector_t next_swap;
55};
56
57/**
58 * The swap_map_handle structure is used for handling swap in
59 * a file-alike way
60 */
61
62struct swap_map_handle {
63 struct swap_map_page *cur;
64 sector_t cur_swap;
65 sector_t first_sector;
66 unsigned int k;
67};
68
69struct swsusp_header {
70 char reserved[PAGE_SIZE - 20 - sizeof(sector_t) - sizeof(int)];
71 sector_t image;
72 unsigned int flags; /* Flags to pass to the "boot" kernel */
73 char orig_sig[10];
74 char sig[10];
75} __attribute__((packed));
76
77static struct swsusp_header *swsusp_header;
78
79/**
80 * The following functions are used for tracing the allocated
81 * swap pages, so that they can be freed in case of an error.
82 */
83
84struct swsusp_extent {
85 struct rb_node node;
86 unsigned long start;
87 unsigned long end;
88};
89
90static struct rb_root swsusp_extents = RB_ROOT;
91
92static int swsusp_extents_insert(unsigned long swap_offset)
93{
94 struct rb_node **new = &(swsusp_extents.rb_node);
95 struct rb_node *parent = NULL;
96 struct swsusp_extent *ext;
97
98 /* Figure out where to put the new node */
99 while (*new) {
100 ext = container_of(*new, struct swsusp_extent, node);
101 parent = *new;
102 if (swap_offset < ext->start) {
103 /* Try to merge */
104 if (swap_offset == ext->start - 1) {
105 ext->start--;
106 return 0;
107 }
108 new = &((*new)->rb_left);
109 } else if (swap_offset > ext->end) {
110 /* Try to merge */
111 if (swap_offset == ext->end + 1) {
112 ext->end++;
113 return 0;
114 }
115 new = &((*new)->rb_right);
116 } else {
117 /* It already is in the tree */
118 return -EINVAL;
119 }
120 }
121 /* Add the new node and rebalance the tree. */
122 ext = kzalloc(sizeof(struct swsusp_extent), GFP_KERNEL);
123 if (!ext)
124 return -ENOMEM;
125
126 ext->start = swap_offset;
127 ext->end = swap_offset;
128 rb_link_node(&ext->node, parent, new);
129 rb_insert_color(&ext->node, &swsusp_extents);
130 return 0;
131}
132
133/**
134 * alloc_swapdev_block - allocate a swap page and register that it has
135 * been allocated, so that it can be freed in case of an error.
136 */
137
138sector_t alloc_swapdev_block(int swap)
139{
140 unsigned long offset;
141
142 offset = swp_offset(get_swap_page_of_type(swap));
143 if (offset) {
144 if (swsusp_extents_insert(offset))
145 swap_free(swp_entry(swap, offset));
146 else
147 return swapdev_block(swap, offset);
148 }
149 return 0;
150}
151
152/**
153 * free_all_swap_pages - free swap pages allocated for saving image data.
154 * It also frees the extents used to register which swap entries had been
155 * allocated.
156 */
157
158void free_all_swap_pages(int swap)
159{
160 struct rb_node *node;
161
162 while ((node = swsusp_extents.rb_node)) {
163 struct swsusp_extent *ext;
164 unsigned long offset;
165
166 ext = container_of(node, struct swsusp_extent, node);
167 rb_erase(node, &swsusp_extents);
168 for (offset = ext->start; offset <= ext->end; offset++)
169 swap_free(swp_entry(swap, offset));
170
171 kfree(ext);
172 }
173}
174
175int swsusp_swap_in_use(void)
176{
177 return (swsusp_extents.rb_node != NULL);
178}
179
180/*
181 * General things
182 */
183
184static unsigned short root_swap = 0xffff;
185struct block_device *hib_resume_bdev;
186
187/*
188 * Saving part
189 */
190
191static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
192{
193 int error;
194
195 hib_bio_read_page(swsusp_resume_block, swsusp_header, NULL);
196 if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||
197 !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {
198 memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);
199 memcpy(swsusp_header->sig, HIBERNATE_SIG, 10);
200 swsusp_header->image = handle->first_sector;
201 swsusp_header->flags = flags;
202 error = hib_bio_write_page(swsusp_resume_block,
203 swsusp_header, NULL);
204 } else {
205 printk(KERN_ERR "PM: Swap header not found!\n");
206 error = -ENODEV;
207 }
208 return error;
209}
210
211/**
212 * swsusp_swap_check - check if the resume device is a swap device
213 * and get its index (if so)
214 *
215 * This is called before saving image
216 */
217static int swsusp_swap_check(void)
218{
219 int res;
220
221 res = swap_type_of(swsusp_resume_device, swsusp_resume_block,
222 &hib_resume_bdev);
223 if (res < 0)
224 return res;
225
226 root_swap = res;
227 res = blkdev_get(hib_resume_bdev, FMODE_WRITE, NULL);
228 if (res)
229 return res;
230
231 res = set_blocksize(hib_resume_bdev, PAGE_SIZE);
232 if (res < 0)
233 blkdev_put(hib_resume_bdev, FMODE_WRITE);
234
235 return res;
236}
237
238/**
239 * write_page - Write one page to given swap location.
240 * @buf: Address we're writing.
241 * @offset: Offset of the swap page we're writing to.
242 * @bio_chain: Link the next write BIO here
243 */
244
245static int write_page(void *buf, sector_t offset, struct bio **bio_chain)
246{
247 void *src;
248
249 if (!offset)
250 return -ENOSPC;
251
252 if (bio_chain) {
253 src = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
254 if (src) {
255 copy_page(src, buf);
256 } else {
257 WARN_ON_ONCE(1);
258 bio_chain = NULL; /* Go synchronous */
259 src = buf;
260 }
261 } else {
262 src = buf;
263 }
264 return hib_bio_write_page(offset, src, bio_chain);
265}
266
267static void release_swap_writer(struct swap_map_handle *handle)
268{
269 if (handle->cur)
270 free_page((unsigned long)handle->cur);
271 handle->cur = NULL;
272}
273
274static int get_swap_writer(struct swap_map_handle *handle)
275{
276 int ret;
277
278 ret = swsusp_swap_check();
279 if (ret) {
280 if (ret != -ENOSPC)
281 printk(KERN_ERR "PM: Cannot find swap device, try "
282 "swapon -a.\n");
283 return ret;
284 }
285 handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL);
286 if (!handle->cur) {
287 ret = -ENOMEM;
288 goto err_close;
289 }
290 handle->cur_swap = alloc_swapdev_block(root_swap);
291 if (!handle->cur_swap) {
292 ret = -ENOSPC;
293 goto err_rel;
294 }
295 handle->k = 0;
296 handle->first_sector = handle->cur_swap;
297 return 0;
298err_rel:
299 release_swap_writer(handle);
300err_close:
301 swsusp_close(FMODE_WRITE);
302 return ret;
303}
304
305static int swap_write_page(struct swap_map_handle *handle, void *buf,
306 struct bio **bio_chain)
307{
308 int error = 0;
309 sector_t offset;
310
311 if (!handle->cur)
312 return -EINVAL;
313 offset = alloc_swapdev_block(root_swap);
314 error = write_page(buf, offset, bio_chain);
315 if (error)
316 return error;
317 handle->cur->entries[handle->k++] = offset;
318 if (handle->k >= MAP_PAGE_ENTRIES) {
319 error = hib_wait_on_bio_chain(bio_chain);
320 if (error)
321 goto out;
322 offset = alloc_swapdev_block(root_swap);
323 if (!offset)
324 return -ENOSPC;
325 handle->cur->next_swap = offset;
326 error = write_page(handle->cur, handle->cur_swap, NULL);
327 if (error)
328 goto out;
329 clear_page(handle->cur);
330 handle->cur_swap = offset;
331 handle->k = 0;
332 }
333 out:
334 return error;
335}
336
337static int flush_swap_writer(struct swap_map_handle *handle)
338{
339 if (handle->cur && handle->cur_swap)
340 return write_page(handle->cur, handle->cur_swap, NULL);
341 else
342 return -EINVAL;
343}
344
345static int swap_writer_finish(struct swap_map_handle *handle,
346 unsigned int flags, int error)
347{
348 if (!error) {
349 flush_swap_writer(handle);
350 printk(KERN_INFO "PM: S");
351 error = mark_swapfiles(handle, flags);
352 printk("|\n");
353 }
354
355 if (error)
356 free_all_swap_pages(root_swap);
357 release_swap_writer(handle);
358 swsusp_close(FMODE_WRITE);
359
360 return error;
361}
362
363/* We need to remember how much compressed data we need to read. */
364#define LZO_HEADER sizeof(size_t)
365
366/* Number of pages/bytes we'll compress at one time. */
367#define LZO_UNC_PAGES 32
368#define LZO_UNC_SIZE (LZO_UNC_PAGES * PAGE_SIZE)
369
370/* Number of pages/bytes we need for compressed data (worst case). */
371#define LZO_CMP_PAGES DIV_ROUND_UP(lzo1x_worst_compress(LZO_UNC_SIZE) + \
372 LZO_HEADER, PAGE_SIZE)
373#define LZO_CMP_SIZE (LZO_CMP_PAGES * PAGE_SIZE)
374
375/**
376 * save_image - save the suspend image data
377 */
378
379static int save_image(struct swap_map_handle *handle,
380 struct snapshot_handle *snapshot,
381 unsigned int nr_to_write)
382{
383 unsigned int m;
384 int ret;
385 int nr_pages;
386 int err2;
387 struct bio *bio;
388 struct timeval start;
389 struct timeval stop;
390
391 printk(KERN_INFO "PM: Saving image data pages (%u pages) ... ",
392 nr_to_write);
393 m = nr_to_write / 100;
394 if (!m)
395 m = 1;
396 nr_pages = 0;
397 bio = NULL;
398 do_gettimeofday(&start);
399 while (1) {
400 ret = snapshot_read_next(snapshot);
401 if (ret <= 0)
402 break;
403 ret = swap_write_page(handle, data_of(*snapshot), &bio);
404 if (ret)
405 break;
406 if (!(nr_pages % m))
407 printk(KERN_CONT "\b\b\b\b%3d%%", nr_pages / m);
408 nr_pages++;
409 }
410 err2 = hib_wait_on_bio_chain(&bio);
411 do_gettimeofday(&stop);
412 if (!ret)
413 ret = err2;
414 if (!ret)
415 printk(KERN_CONT "\b\b\b\bdone\n");
416 else
417 printk(KERN_CONT "\n");
418 swsusp_show_speed(&start, &stop, nr_to_write, "Wrote");
419 return ret;
420}
421
422
423/**
424 * save_image_lzo - Save the suspend image data compressed with LZO.
425 * @handle: Swap mam handle to use for saving the image.
426 * @snapshot: Image to read data from.
427 * @nr_to_write: Number of pages to save.
428 */
429static int save_image_lzo(struct swap_map_handle *handle,
430 struct snapshot_handle *snapshot,
431 unsigned int nr_to_write)
432{
433 unsigned int m;
434 int ret = 0;
435 int nr_pages;
436 int err2;
437 struct bio *bio;
438 struct timeval start;
439 struct timeval stop;
440 size_t off, unc_len, cmp_len;
441 unsigned char *unc, *cmp, *wrk, *page;
442
443 page = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
444 if (!page) {
445 printk(KERN_ERR "PM: Failed to allocate LZO page\n");
446 return -ENOMEM;
447 }
448
449 wrk = vmalloc(LZO1X_1_MEM_COMPRESS);
450 if (!wrk) {
451 printk(KERN_ERR "PM: Failed to allocate LZO workspace\n");
452 free_page((unsigned long)page);
453 return -ENOMEM;
454 }
455
456 unc = vmalloc(LZO_UNC_SIZE);
457 if (!unc) {
458 printk(KERN_ERR "PM: Failed to allocate LZO uncompressed\n");
459 vfree(wrk);
460 free_page((unsigned long)page);
461 return -ENOMEM;
462 }
463
464 cmp = vmalloc(LZO_CMP_SIZE);
465 if (!cmp) {
466 printk(KERN_ERR "PM: Failed to allocate LZO compressed\n");
467 vfree(unc);
468 vfree(wrk);
469 free_page((unsigned long)page);
470 return -ENOMEM;
471 }
472
473 printk(KERN_INFO
474 "PM: Compressing and saving image data (%u pages) ... ",
475 nr_to_write);
476 m = nr_to_write / 100;
477 if (!m)
478 m = 1;
479 nr_pages = 0;
480 bio = NULL;
481 do_gettimeofday(&start);
482 for (;;) {
483 for (off = 0; off < LZO_UNC_SIZE; off += PAGE_SIZE) {
484 ret = snapshot_read_next(snapshot);
485 if (ret < 0)
486 goto out_finish;
487
488 if (!ret)
489 break;
490
491 memcpy(unc + off, data_of(*snapshot), PAGE_SIZE);
492
493 if (!(nr_pages % m))
494 printk(KERN_CONT "\b\b\b\b%3d%%", nr_pages / m);
495 nr_pages++;
496 }
497
498 if (!off)
499 break;
500
501 unc_len = off;
502 ret = lzo1x_1_compress(unc, unc_len,
503 cmp + LZO_HEADER, &cmp_len, wrk);
504 if (ret < 0) {
505 printk(KERN_ERR "PM: LZO compression failed\n");
506 break;
507 }
508
509 if (unlikely(!cmp_len ||
510 cmp_len > lzo1x_worst_compress(unc_len))) {
511 printk(KERN_ERR "PM: Invalid LZO compressed length\n");
512 ret = -1;
513 break;
514 }
515
516 *(size_t *)cmp = cmp_len;
517
518 /*
519 * Given we are writing one page at a time to disk, we copy
520 * that much from the buffer, although the last bit will likely
521 * be smaller than full page. This is OK - we saved the length
522 * of the compressed data, so any garbage at the end will be
523 * discarded when we read it.
524 */
525 for (off = 0; off < LZO_HEADER + cmp_len; off += PAGE_SIZE) {
526 memcpy(page, cmp + off, PAGE_SIZE);
527
528 ret = swap_write_page(handle, page, &bio);
529 if (ret)
530 goto out_finish;
531 }
532 }
533
534out_finish:
535 err2 = hib_wait_on_bio_chain(&bio);
536 do_gettimeofday(&stop);
537 if (!ret)
538 ret = err2;
539 if (!ret)
540 printk(KERN_CONT "\b\b\b\bdone\n");
541 else
542 printk(KERN_CONT "\n");
543 swsusp_show_speed(&start, &stop, nr_to_write, "Wrote");
544
545 vfree(cmp);
546 vfree(unc);
547 vfree(wrk);
548 free_page((unsigned long)page);
549
550 return ret;
551}
552
553/**
554 * enough_swap - Make sure we have enough swap to save the image.
555 *
556 * Returns TRUE or FALSE after checking the total amount of swap
557 * space avaiable from the resume partition.
558 */
559
560static int enough_swap(unsigned int nr_pages, unsigned int flags)
561{
562 unsigned int free_swap = count_swap_pages(root_swap, 1);
563 unsigned int required;
564
565 pr_debug("PM: Free swap pages: %u\n", free_swap);
566
567 required = PAGES_FOR_IO + ((flags & SF_NOCOMPRESS_MODE) ?
568 nr_pages : (nr_pages * LZO_CMP_PAGES) / LZO_UNC_PAGES + 1);
569 return free_swap > required;
570}
571
572/**
573 * swsusp_write - Write entire image and metadata.
574 * @flags: flags to pass to the "boot" kernel in the image header
575 *
576 * It is important _NOT_ to umount filesystems at this point. We want
577 * them synced (in case something goes wrong) but we DO not want to mark
578 * filesystem clean: it is not. (And it does not matter, if we resume
579 * correctly, we'll mark system clean, anyway.)
580 */
581
582int swsusp_write(unsigned int flags)
583{
584 struct swap_map_handle handle;
585 struct snapshot_handle snapshot;
586 struct swsusp_info *header;
587 unsigned long pages;
588 int error;
589
590 pages = snapshot_get_image_size();
591 error = get_swap_writer(&handle);
592 if (error) {
593 printk(KERN_ERR "PM: Cannot get swap writer\n");
594 return error;
595 }
596 if (!enough_swap(pages, flags)) {
597 printk(KERN_ERR "PM: Not enough free swap\n");
598 error = -ENOSPC;
599 goto out_finish;
600 }
601 memset(&snapshot, 0, sizeof(struct snapshot_handle));
602 error = snapshot_read_next(&snapshot);
603 if (error < PAGE_SIZE) {
604 if (error >= 0)
605 error = -EFAULT;
606
607 goto out_finish;
608 }
609 header = (struct swsusp_info *)data_of(snapshot);
610 error = swap_write_page(&handle, header, NULL);
611 if (!error) {
612 error = (flags & SF_NOCOMPRESS_MODE) ?
613 save_image(&handle, &snapshot, pages - 1) :
614 save_image_lzo(&handle, &snapshot, pages - 1);
615 }
616out_finish:
617 error = swap_writer_finish(&handle, flags, error);
618 return error;
619}
620
621/**
622 * The following functions allow us to read data using a swap map
623 * in a file-alike way
624 */
625
626static void release_swap_reader(struct swap_map_handle *handle)
627{
628 if (handle->cur)
629 free_page((unsigned long)handle->cur);
630 handle->cur = NULL;
631}
632
633static int get_swap_reader(struct swap_map_handle *handle,
634 unsigned int *flags_p)
635{
636 int error;
637
638 *flags_p = swsusp_header->flags;
639
640 if (!swsusp_header->image) /* how can this happen? */
641 return -EINVAL;
642
643 handle->cur = (struct swap_map_page *)get_zeroed_page(__GFP_WAIT | __GFP_HIGH);
644 if (!handle->cur)
645 return -ENOMEM;
646
647 error = hib_bio_read_page(swsusp_header->image, handle->cur, NULL);
648 if (error) {
649 release_swap_reader(handle);
650 return error;
651 }
652 handle->k = 0;
653 return 0;
654}
655
656static int swap_read_page(struct swap_map_handle *handle, void *buf,
657 struct bio **bio_chain)
658{
659 sector_t offset;
660 int error;
661
662 if (!handle->cur)
663 return -EINVAL;
664 offset = handle->cur->entries[handle->k];
665 if (!offset)
666 return -EFAULT;
667 error = hib_bio_read_page(offset, buf, bio_chain);
668 if (error)
669 return error;
670 if (++handle->k >= MAP_PAGE_ENTRIES) {
671 error = hib_wait_on_bio_chain(bio_chain);
672 handle->k = 0;
673 offset = handle->cur->next_swap;
674 if (!offset)
675 release_swap_reader(handle);
676 else if (!error)
677 error = hib_bio_read_page(offset, handle->cur, NULL);
678 }
679 return error;
680}
681
682static int swap_reader_finish(struct swap_map_handle *handle)
683{
684 release_swap_reader(handle);
685
686 return 0;
687}
688
689/**
690 * load_image - load the image using the swap map handle
691 * @handle and the snapshot handle @snapshot
692 * (assume there are @nr_pages pages to load)
693 */
694
695static int load_image(struct swap_map_handle *handle,
696 struct snapshot_handle *snapshot,
697 unsigned int nr_to_read)
698{
699 unsigned int m;
700 int error = 0;
701 struct timeval start;
702 struct timeval stop;
703 struct bio *bio;
704 int err2;
705 unsigned nr_pages;
706
707 printk(KERN_INFO "PM: Loading image data pages (%u pages) ... ",
708 nr_to_read);
709 m = nr_to_read / 100;
710 if (!m)
711 m = 1;
712 nr_pages = 0;
713 bio = NULL;
714 do_gettimeofday(&start);
715 for ( ; ; ) {
716 error = snapshot_write_next(snapshot);
717 if (error <= 0)
718 break;
719 error = swap_read_page(handle, data_of(*snapshot), &bio);
720 if (error)
721 break;
722 if (snapshot->sync_read)
723 error = hib_wait_on_bio_chain(&bio);
724 if (error)
725 break;
726 if (!(nr_pages % m))
727 printk("\b\b\b\b%3d%%", nr_pages / m);
728 nr_pages++;
729 }
730 err2 = hib_wait_on_bio_chain(&bio);
731 do_gettimeofday(&stop);
732 if (!error)
733 error = err2;
734 if (!error) {
735 printk("\b\b\b\bdone\n");
736 snapshot_write_finalize(snapshot);
737 if (!snapshot_image_loaded(snapshot))
738 error = -ENODATA;
739 } else
740 printk("\n");
741 swsusp_show_speed(&start, &stop, nr_to_read, "Read");
742 return error;
743}
744
745/**
746 * load_image_lzo - Load compressed image data and decompress them with LZO.
747 * @handle: Swap map handle to use for loading data.
748 * @snapshot: Image to copy uncompressed data into.
749 * @nr_to_read: Number of pages to load.
750 */
751static int load_image_lzo(struct swap_map_handle *handle,
752 struct snapshot_handle *snapshot,
753 unsigned int nr_to_read)
754{
755 unsigned int m;
756 int error = 0;
757 struct bio *bio;
758 struct timeval start;
759 struct timeval stop;
760 unsigned nr_pages;
761 size_t i, off, unc_len, cmp_len;
762 unsigned char *unc, *cmp, *page[LZO_CMP_PAGES];
763
764 for (i = 0; i < LZO_CMP_PAGES; i++) {
765 page[i] = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
766 if (!page[i]) {
767 printk(KERN_ERR "PM: Failed to allocate LZO page\n");
768
769 while (i)
770 free_page((unsigned long)page[--i]);
771
772 return -ENOMEM;
773 }
774 }
775
776 unc = vmalloc(LZO_UNC_SIZE);
777 if (!unc) {
778 printk(KERN_ERR "PM: Failed to allocate LZO uncompressed\n");
779
780 for (i = 0; i < LZO_CMP_PAGES; i++)
781 free_page((unsigned long)page[i]);
782
783 return -ENOMEM;
784 }
785
786 cmp = vmalloc(LZO_CMP_SIZE);
787 if (!cmp) {
788 printk(KERN_ERR "PM: Failed to allocate LZO compressed\n");
789
790 vfree(unc);
791 for (i = 0; i < LZO_CMP_PAGES; i++)
792 free_page((unsigned long)page[i]);
793
794 return -ENOMEM;
795 }
796
797 printk(KERN_INFO
798 "PM: Loading and decompressing image data (%u pages) ... ",
799 nr_to_read);
800 m = nr_to_read / 100;
801 if (!m)
802 m = 1;
803 nr_pages = 0;
804 bio = NULL;
805 do_gettimeofday(&start);
806
807 error = snapshot_write_next(snapshot);
808 if (error <= 0)
809 goto out_finish;
810
811 for (;;) {
812 error = swap_read_page(handle, page[0], NULL); /* sync */
813 if (error)
814 break;
815
816 cmp_len = *(size_t *)page[0];
817 if (unlikely(!cmp_len ||
818 cmp_len > lzo1x_worst_compress(LZO_UNC_SIZE))) {
819 printk(KERN_ERR "PM: Invalid LZO compressed length\n");
820 error = -1;
821 break;
822 }
823
824 for (off = PAGE_SIZE, i = 1;
825 off < LZO_HEADER + cmp_len; off += PAGE_SIZE, i++) {
826 error = swap_read_page(handle, page[i], &bio);
827 if (error)
828 goto out_finish;
829 }
830
831 error = hib_wait_on_bio_chain(&bio); /* need all data now */
832 if (error)
833 goto out_finish;
834
835 for (off = 0, i = 0;
836 off < LZO_HEADER + cmp_len; off += PAGE_SIZE, i++) {
837 memcpy(cmp + off, page[i], PAGE_SIZE);
838 }
839
840 unc_len = LZO_UNC_SIZE;
841 error = lzo1x_decompress_safe(cmp + LZO_HEADER, cmp_len,
842 unc, &unc_len);
843 if (error < 0) {
844 printk(KERN_ERR "PM: LZO decompression failed\n");
845 break;
846 }
847
848 if (unlikely(!unc_len ||
849 unc_len > LZO_UNC_SIZE ||
850 unc_len & (PAGE_SIZE - 1))) {
851 printk(KERN_ERR "PM: Invalid LZO uncompressed length\n");
852 error = -1;
853 break;
854 }
855
856 for (off = 0; off < unc_len; off += PAGE_SIZE) {
857 memcpy(data_of(*snapshot), unc + off, PAGE_SIZE);
858
859 if (!(nr_pages % m))
860 printk("\b\b\b\b%3d%%", nr_pages / m);
861 nr_pages++;
862
863 error = snapshot_write_next(snapshot);
864 if (error <= 0)
865 goto out_finish;
866 }
867 }
868
869out_finish:
870 do_gettimeofday(&stop);
871 if (!error) {
872 printk("\b\b\b\bdone\n");
873 snapshot_write_finalize(snapshot);
874 if (!snapshot_image_loaded(snapshot))
875 error = -ENODATA;
876 } else
877 printk("\n");
878 swsusp_show_speed(&start, &stop, nr_to_read, "Read");
879
880 vfree(cmp);
881 vfree(unc);
882 for (i = 0; i < LZO_CMP_PAGES; i++)
883 free_page((unsigned long)page[i]);
884
885 return error;
886}
887
888/**
889 * swsusp_read - read the hibernation image.
890 * @flags_p: flags passed by the "frozen" kernel in the image header should
891 * be written into this memory location
892 */
893
894int swsusp_read(unsigned int *flags_p)
895{
896 int error;
897 struct swap_map_handle handle;
898 struct snapshot_handle snapshot;
899 struct swsusp_info *header;
900
901 memset(&snapshot, 0, sizeof(struct snapshot_handle));
902 error = snapshot_write_next(&snapshot);
903 if (error < PAGE_SIZE)
904 return error < 0 ? error : -EFAULT;
905 header = (struct swsusp_info *)data_of(snapshot);
906 error = get_swap_reader(&handle, flags_p);
907 if (error)
908 goto end;
909 if (!error)
910 error = swap_read_page(&handle, header, NULL);
911 if (!error) {
912 error = (*flags_p & SF_NOCOMPRESS_MODE) ?
913 load_image(&handle, &snapshot, header->pages - 1) :
914 load_image_lzo(&handle, &snapshot, header->pages - 1);
915 }
916 swap_reader_finish(&handle);
917end:
918 if (!error)
919 pr_debug("PM: Image successfully loaded\n");
920 else
921 pr_debug("PM: Error %d resuming\n", error);
922 return error;
923}
924
925/**
926 * swsusp_check - Check for swsusp signature in the resume device
927 */
928
929int swsusp_check(void)
930{
931 int error;
932
933 hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device,
934 FMODE_READ, NULL);
935 if (!IS_ERR(hib_resume_bdev)) {
936 set_blocksize(hib_resume_bdev, PAGE_SIZE);
937 clear_page(swsusp_header);
938 error = hib_bio_read_page(swsusp_resume_block,
939 swsusp_header, NULL);
940 if (error)
941 goto put;
942
943 if (!memcmp(HIBERNATE_SIG, swsusp_header->sig, 10)) {
944 memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10);
945 /* Reset swap signature now */
946 error = hib_bio_write_page(swsusp_resume_block,
947 swsusp_header, NULL);
948 } else {
949 error = -EINVAL;
950 }
951
952put:
953 if (error)
954 blkdev_put(hib_resume_bdev, FMODE_READ);
955 else
956 pr_debug("PM: Image signature found, resuming\n");
957 } else {
958 error = PTR_ERR(hib_resume_bdev);
959 }
960
961 if (error)
962 pr_debug("PM: Image not found (code %d)\n", error);
963
964 return error;
965}
966
967/**
968 * swsusp_close - close swap device.
969 */
970
971void swsusp_close(fmode_t mode)
972{
973 if (IS_ERR(hib_resume_bdev)) {
974 pr_debug("PM: Image device not initialised\n");
975 return;
976 }
977
978 blkdev_put(hib_resume_bdev, mode);
979}
980
981static int swsusp_header_init(void)
982{
983 swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);
984 if (!swsusp_header)
985 panic("Could not allocate memory for swsusp_header\n");
986 return 0;
987}
988
989core_initcall(swsusp_header_init);