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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/kernel/power/swap.c
4 *
5 * This file provides functions for reading the suspend image from
6 * and writing it to a swap partition.
7 *
8 * Copyright (C) 1998,2001-2005 Pavel Machek <pavel@ucw.cz>
9 * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl>
10 * Copyright (C) 2010-2012 Bojan Smojver <bojan@rexursive.com>
11 */
12
13#define pr_fmt(fmt) "PM: " fmt
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 * 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.
43 */
44static bool clean_pages_on_read;
45static bool clean_pages_on_decompress;
46
47/*
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.
53 *
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.
57 *
58 * During resume we pick up all swap_map_page structures into a list.
59 */
60
61#define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(sector_t) - 1)
62
63/*
64 * Number of free pages that are not high.
65 */
66static inline unsigned long low_free_pages(void)
67{
68 return nr_free_pages() - nr_free_highpages();
69}
70
71/*
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.
74 */
75static inline unsigned long reqd_free_pages(void)
76{
77 return low_free_pages() / 2;
78}
79
80struct swap_map_page {
81 sector_t entries[MAP_PAGE_ENTRIES];
82 sector_t next_swap;
83};
84
85struct swap_map_page_list {
86 struct swap_map_page *map;
87 struct swap_map_page_list *next;
88};
89
90/**
91 * The swap_map_handle structure is used for handling swap in
92 * a file-alike way
93 */
94
95struct swap_map_handle {
96 struct swap_map_page *cur;
97 struct swap_map_page_list *maps;
98 sector_t cur_swap;
99 sector_t first_sector;
100 unsigned int k;
101 unsigned long reqd_free_pages;
102 u32 crc32;
103};
104
105struct swsusp_header {
106 char reserved[PAGE_SIZE - 20 - sizeof(sector_t) - sizeof(int) -
107 sizeof(u32)];
108 u32 crc32;
109 sector_t image;
110 unsigned int flags; /* Flags to pass to the "boot" kernel */
111 char orig_sig[10];
112 char sig[10];
113} __packed;
114
115static struct swsusp_header *swsusp_header;
116
117/**
118 * The following functions are used for tracing the allocated
119 * swap pages, so that they can be freed in case of an error.
120 */
121
122struct swsusp_extent {
123 struct rb_node node;
124 unsigned long start;
125 unsigned long end;
126};
127
128static struct rb_root swsusp_extents = RB_ROOT;
129
130static int swsusp_extents_insert(unsigned long swap_offset)
131{
132 struct rb_node **new = &(swsusp_extents.rb_node);
133 struct rb_node *parent = NULL;
134 struct swsusp_extent *ext;
135
136 /* Figure out where to put the new node */
137 while (*new) {
138 ext = rb_entry(*new, struct swsusp_extent, node);
139 parent = *new;
140 if (swap_offset < ext->start) {
141 /* Try to merge */
142 if (swap_offset == ext->start - 1) {
143 ext->start--;
144 return 0;
145 }
146 new = &((*new)->rb_left);
147 } else if (swap_offset > ext->end) {
148 /* Try to merge */
149 if (swap_offset == ext->end + 1) {
150 ext->end++;
151 return 0;
152 }
153 new = &((*new)->rb_right);
154 } else {
155 /* It already is in the tree */
156 return -EINVAL;
157 }
158 }
159 /* Add the new node and rebalance the tree. */
160 ext = kzalloc(sizeof(struct swsusp_extent), GFP_KERNEL);
161 if (!ext)
162 return -ENOMEM;
163
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);
168 return 0;
169}
170
171/**
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.
174 */
175
176sector_t alloc_swapdev_block(int swap)
177{
178 unsigned long offset;
179
180 offset = swp_offset(get_swap_page_of_type(swap));
181 if (offset) {
182 if (swsusp_extents_insert(offset))
183 swap_free(swp_entry(swap, offset));
184 else
185 return swapdev_block(swap, offset);
186 }
187 return 0;
188}
189
190/**
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
193 * allocated.
194 */
195
196void free_all_swap_pages(int swap)
197{
198 struct rb_node *node;
199
200 while ((node = swsusp_extents.rb_node)) {
201 struct swsusp_extent *ext;
202 unsigned long offset;
203
204 ext = rb_entry(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));
208
209 kfree(ext);
210 }
211}
212
213int swsusp_swap_in_use(void)
214{
215 return (swsusp_extents.rb_node != NULL);
216}
217
218/*
219 * General things
220 */
221
222static unsigned short root_swap = 0xffff;
223static struct block_device *hib_resume_bdev;
224
225struct hib_bio_batch {
226 atomic_t count;
227 wait_queue_head_t wait;
228 blk_status_t error;
229};
230
231static void hib_init_batch(struct hib_bio_batch *hb)
232{
233 atomic_set(&hb->count, 0);
234 init_waitqueue_head(&hb->wait);
235 hb->error = BLK_STS_OK;
236}
237
238static void hib_end_io(struct bio *bio)
239{
240 struct hib_bio_batch *hb = bio->bi_private;
241 struct page *page = bio_first_page_all(bio);
242
243 if (bio->bi_status) {
244 pr_alert("Read-error on swap-device (%u:%u:%Lu)\n",
245 MAJOR(bio_dev(bio)), MINOR(bio_dev(bio)),
246 (unsigned long long)bio->bi_iter.bi_sector);
247 }
248
249 if (bio_data_dir(bio) == WRITE)
250 put_page(page);
251 else if (clean_pages_on_read)
252 flush_icache_range((unsigned long)page_address(page),
253 (unsigned long)page_address(page) + PAGE_SIZE);
254
255 if (bio->bi_status && !hb->error)
256 hb->error = bio->bi_status;
257 if (atomic_dec_and_test(&hb->count))
258 wake_up(&hb->wait);
259
260 bio_put(bio);
261}
262
263static int hib_submit_io(int op, int op_flags, pgoff_t page_off, void *addr,
264 struct hib_bio_batch *hb)
265{
266 struct page *page = virt_to_page(addr);
267 struct bio *bio;
268 int error = 0;
269
270 bio = bio_alloc(GFP_NOIO | __GFP_HIGH, 1);
271 bio->bi_iter.bi_sector = page_off * (PAGE_SIZE >> 9);
272 bio_set_dev(bio, hib_resume_bdev);
273 bio_set_op_attrs(bio, op, op_flags);
274
275 if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
276 pr_err("Adding page to bio failed at %llu\n",
277 (unsigned long long)bio->bi_iter.bi_sector);
278 bio_put(bio);
279 return -EFAULT;
280 }
281
282 if (hb) {
283 bio->bi_end_io = hib_end_io;
284 bio->bi_private = hb;
285 atomic_inc(&hb->count);
286 submit_bio(bio);
287 } else {
288 error = submit_bio_wait(bio);
289 bio_put(bio);
290 }
291
292 return error;
293}
294
295static blk_status_t hib_wait_io(struct hib_bio_batch *hb)
296{
297 wait_event(hb->wait, atomic_read(&hb->count) == 0);
298 return blk_status_to_errno(hb->error);
299}
300
301/*
302 * Saving part
303 */
304
305static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
306{
307 int error;
308
309 hib_submit_io(REQ_OP_READ, 0, swsusp_resume_block,
310 swsusp_header, NULL);
311 if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||
312 !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {
313 memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);
314 memcpy(swsusp_header->sig, HIBERNATE_SIG, 10);
315 swsusp_header->image = handle->first_sector;
316 swsusp_header->flags = flags;
317 if (flags & SF_CRC32_MODE)
318 swsusp_header->crc32 = handle->crc32;
319 error = hib_submit_io(REQ_OP_WRITE, REQ_SYNC,
320 swsusp_resume_block, swsusp_header, NULL);
321 } else {
322 pr_err("Swap header not found!\n");
323 error = -ENODEV;
324 }
325 return error;
326}
327
328/**
329 * swsusp_swap_check - check if the resume device is a swap device
330 * and get its index (if so)
331 *
332 * This is called before saving image
333 */
334static int swsusp_swap_check(void)
335{
336 int res;
337
338 res = swap_type_of(swsusp_resume_device, swsusp_resume_block,
339 &hib_resume_bdev);
340 if (res < 0)
341 return res;
342
343 root_swap = res;
344 res = blkdev_get(hib_resume_bdev, FMODE_WRITE, NULL);
345 if (res)
346 return res;
347
348 res = set_blocksize(hib_resume_bdev, PAGE_SIZE);
349 if (res < 0)
350 blkdev_put(hib_resume_bdev, FMODE_WRITE);
351
352 /*
353 * Update the resume device to the one actually used,
354 * so the test_resume mode can use it in case it is
355 * invoked from hibernate() to test the snapshot.
356 */
357 swsusp_resume_device = hib_resume_bdev->bd_dev;
358 return res;
359}
360
361/**
362 * write_page - Write one page to given swap location.
363 * @buf: Address we're writing.
364 * @offset: Offset of the swap page we're writing to.
365 * @hb: bio completion batch
366 */
367
368static int write_page(void *buf, sector_t offset, struct hib_bio_batch *hb)
369{
370 void *src;
371 int ret;
372
373 if (!offset)
374 return -ENOSPC;
375
376 if (hb) {
377 src = (void *)__get_free_page(GFP_NOIO | __GFP_NOWARN |
378 __GFP_NORETRY);
379 if (src) {
380 copy_page(src, buf);
381 } else {
382 ret = hib_wait_io(hb); /* Free pages */
383 if (ret)
384 return ret;
385 src = (void *)__get_free_page(GFP_NOIO |
386 __GFP_NOWARN |
387 __GFP_NORETRY);
388 if (src) {
389 copy_page(src, buf);
390 } else {
391 WARN_ON_ONCE(1);
392 hb = NULL; /* Go synchronous */
393 src = buf;
394 }
395 }
396 } else {
397 src = buf;
398 }
399 return hib_submit_io(REQ_OP_WRITE, REQ_SYNC, offset, src, hb);
400}
401
402static void release_swap_writer(struct swap_map_handle *handle)
403{
404 if (handle->cur)
405 free_page((unsigned long)handle->cur);
406 handle->cur = NULL;
407}
408
409static int get_swap_writer(struct swap_map_handle *handle)
410{
411 int ret;
412
413 ret = swsusp_swap_check();
414 if (ret) {
415 if (ret != -ENOSPC)
416 pr_err("Cannot find swap device, try swapon -a\n");
417 return ret;
418 }
419 handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL);
420 if (!handle->cur) {
421 ret = -ENOMEM;
422 goto err_close;
423 }
424 handle->cur_swap = alloc_swapdev_block(root_swap);
425 if (!handle->cur_swap) {
426 ret = -ENOSPC;
427 goto err_rel;
428 }
429 handle->k = 0;
430 handle->reqd_free_pages = reqd_free_pages();
431 handle->first_sector = handle->cur_swap;
432 return 0;
433err_rel:
434 release_swap_writer(handle);
435err_close:
436 swsusp_close(FMODE_WRITE);
437 return ret;
438}
439
440static int swap_write_page(struct swap_map_handle *handle, void *buf,
441 struct hib_bio_batch *hb)
442{
443 int error = 0;
444 sector_t offset;
445
446 if (!handle->cur)
447 return -EINVAL;
448 offset = alloc_swapdev_block(root_swap);
449 error = write_page(buf, offset, hb);
450 if (error)
451 return error;
452 handle->cur->entries[handle->k++] = offset;
453 if (handle->k >= MAP_PAGE_ENTRIES) {
454 offset = alloc_swapdev_block(root_swap);
455 if (!offset)
456 return -ENOSPC;
457 handle->cur->next_swap = offset;
458 error = write_page(handle->cur, handle->cur_swap, hb);
459 if (error)
460 goto out;
461 clear_page(handle->cur);
462 handle->cur_swap = offset;
463 handle->k = 0;
464
465 if (hb && low_free_pages() <= handle->reqd_free_pages) {
466 error = hib_wait_io(hb);
467 if (error)
468 goto out;
469 /*
470 * Recalculate the number of required free pages, to
471 * make sure we never take more than half.
472 */
473 handle->reqd_free_pages = reqd_free_pages();
474 }
475 }
476 out:
477 return error;
478}
479
480static int flush_swap_writer(struct swap_map_handle *handle)
481{
482 if (handle->cur && handle->cur_swap)
483 return write_page(handle->cur, handle->cur_swap, NULL);
484 else
485 return -EINVAL;
486}
487
488static int swap_writer_finish(struct swap_map_handle *handle,
489 unsigned int flags, int error)
490{
491 if (!error) {
492 flush_swap_writer(handle);
493 pr_info("S");
494 error = mark_swapfiles(handle, flags);
495 pr_cont("|\n");
496 }
497
498 if (error)
499 free_all_swap_pages(root_swap);
500 release_swap_writer(handle);
501 swsusp_close(FMODE_WRITE);
502
503 return error;
504}
505
506/* We need to remember how much compressed data we need to read. */
507#define LZO_HEADER sizeof(size_t)
508
509/* Number of pages/bytes we'll compress at one time. */
510#define LZO_UNC_PAGES 32
511#define LZO_UNC_SIZE (LZO_UNC_PAGES * PAGE_SIZE)
512
513/* Number of pages/bytes we need for compressed data (worst case). */
514#define LZO_CMP_PAGES DIV_ROUND_UP(lzo1x_worst_compress(LZO_UNC_SIZE) + \
515 LZO_HEADER, PAGE_SIZE)
516#define LZO_CMP_SIZE (LZO_CMP_PAGES * PAGE_SIZE)
517
518/* Maximum number of threads for compression/decompression. */
519#define LZO_THREADS 3
520
521/* Minimum/maximum number of pages for read buffering. */
522#define LZO_MIN_RD_PAGES 1024
523#define LZO_MAX_RD_PAGES 8192
524
525
526/**
527 * save_image - save the suspend image data
528 */
529
530static int save_image(struct swap_map_handle *handle,
531 struct snapshot_handle *snapshot,
532 unsigned int nr_to_write)
533{
534 unsigned int m;
535 int ret;
536 int nr_pages;
537 int err2;
538 struct hib_bio_batch hb;
539 ktime_t start;
540 ktime_t stop;
541
542 hib_init_batch(&hb);
543
544 pr_info("Saving image data pages (%u pages)...\n",
545 nr_to_write);
546 m = nr_to_write / 10;
547 if (!m)
548 m = 1;
549 nr_pages = 0;
550 start = ktime_get();
551 while (1) {
552 ret = snapshot_read_next(snapshot);
553 if (ret <= 0)
554 break;
555 ret = swap_write_page(handle, data_of(*snapshot), &hb);
556 if (ret)
557 break;
558 if (!(nr_pages % m))
559 pr_info("Image saving progress: %3d%%\n",
560 nr_pages / m * 10);
561 nr_pages++;
562 }
563 err2 = hib_wait_io(&hb);
564 stop = ktime_get();
565 if (!ret)
566 ret = err2;
567 if (!ret)
568 pr_info("Image saving done\n");
569 swsusp_show_speed(start, stop, nr_to_write, "Wrote");
570 return ret;
571}
572
573/**
574 * Structure used for CRC32.
575 */
576struct crc_data {
577 struct task_struct *thr; /* thread */
578 atomic_t ready; /* ready to start flag */
579 atomic_t stop; /* ready to stop flag */
580 unsigned run_threads; /* nr current threads */
581 wait_queue_head_t go; /* start crc update */
582 wait_queue_head_t done; /* crc update done */
583 u32 *crc32; /* points to handle's crc32 */
584 size_t *unc_len[LZO_THREADS]; /* uncompressed lengths */
585 unsigned char *unc[LZO_THREADS]; /* uncompressed data */
586};
587
588/**
589 * CRC32 update function that runs in its own thread.
590 */
591static int crc32_threadfn(void *data)
592{
593 struct crc_data *d = data;
594 unsigned i;
595
596 while (1) {
597 wait_event(d->go, atomic_read(&d->ready) ||
598 kthread_should_stop());
599 if (kthread_should_stop()) {
600 d->thr = NULL;
601 atomic_set(&d->stop, 1);
602 wake_up(&d->done);
603 break;
604 }
605 atomic_set(&d->ready, 0);
606
607 for (i = 0; i < d->run_threads; i++)
608 *d->crc32 = crc32_le(*d->crc32,
609 d->unc[i], *d->unc_len[i]);
610 atomic_set(&d->stop, 1);
611 wake_up(&d->done);
612 }
613 return 0;
614}
615/**
616 * Structure used for LZO data compression.
617 */
618struct cmp_data {
619 struct task_struct *thr; /* thread */
620 atomic_t ready; /* ready to start flag */
621 atomic_t stop; /* ready to stop flag */
622 int ret; /* return code */
623 wait_queue_head_t go; /* start compression */
624 wait_queue_head_t done; /* compression done */
625 size_t unc_len; /* uncompressed length */
626 size_t cmp_len; /* compressed length */
627 unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */
628 unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */
629 unsigned char wrk[LZO1X_1_MEM_COMPRESS]; /* compression workspace */
630};
631
632/**
633 * Compression function that runs in its own thread.
634 */
635static int lzo_compress_threadfn(void *data)
636{
637 struct cmp_data *d = data;
638
639 while (1) {
640 wait_event(d->go, atomic_read(&d->ready) ||
641 kthread_should_stop());
642 if (kthread_should_stop()) {
643 d->thr = NULL;
644 d->ret = -1;
645 atomic_set(&d->stop, 1);
646 wake_up(&d->done);
647 break;
648 }
649 atomic_set(&d->ready, 0);
650
651 d->ret = lzo1x_1_compress(d->unc, d->unc_len,
652 d->cmp + LZO_HEADER, &d->cmp_len,
653 d->wrk);
654 atomic_set(&d->stop, 1);
655 wake_up(&d->done);
656 }
657 return 0;
658}
659
660/**
661 * save_image_lzo - Save the suspend image data compressed with LZO.
662 * @handle: Swap map handle to use for saving the image.
663 * @snapshot: Image to read data from.
664 * @nr_to_write: Number of pages to save.
665 */
666static int save_image_lzo(struct swap_map_handle *handle,
667 struct snapshot_handle *snapshot,
668 unsigned int nr_to_write)
669{
670 unsigned int m;
671 int ret = 0;
672 int nr_pages;
673 int err2;
674 struct hib_bio_batch hb;
675 ktime_t start;
676 ktime_t stop;
677 size_t off;
678 unsigned thr, run_threads, nr_threads;
679 unsigned char *page = NULL;
680 struct cmp_data *data = NULL;
681 struct crc_data *crc = NULL;
682
683 hib_init_batch(&hb);
684
685 /*
686 * We'll limit the number of threads for compression to limit memory
687 * footprint.
688 */
689 nr_threads = num_online_cpus() - 1;
690 nr_threads = clamp_val(nr_threads, 1, LZO_THREADS);
691
692 page = (void *)__get_free_page(GFP_NOIO | __GFP_HIGH);
693 if (!page) {
694 pr_err("Failed to allocate LZO page\n");
695 ret = -ENOMEM;
696 goto out_clean;
697 }
698
699 data = vmalloc(array_size(nr_threads, sizeof(*data)));
700 if (!data) {
701 pr_err("Failed to allocate LZO data\n");
702 ret = -ENOMEM;
703 goto out_clean;
704 }
705 for (thr = 0; thr < nr_threads; thr++)
706 memset(&data[thr], 0, offsetof(struct cmp_data, go));
707
708 crc = kmalloc(sizeof(*crc), GFP_KERNEL);
709 if (!crc) {
710 pr_err("Failed to allocate crc\n");
711 ret = -ENOMEM;
712 goto out_clean;
713 }
714 memset(crc, 0, offsetof(struct crc_data, go));
715
716 /*
717 * Start the compression threads.
718 */
719 for (thr = 0; thr < nr_threads; thr++) {
720 init_waitqueue_head(&data[thr].go);
721 init_waitqueue_head(&data[thr].done);
722
723 data[thr].thr = kthread_run(lzo_compress_threadfn,
724 &data[thr],
725 "image_compress/%u", thr);
726 if (IS_ERR(data[thr].thr)) {
727 data[thr].thr = NULL;
728 pr_err("Cannot start compression threads\n");
729 ret = -ENOMEM;
730 goto out_clean;
731 }
732 }
733
734 /*
735 * Start the CRC32 thread.
736 */
737 init_waitqueue_head(&crc->go);
738 init_waitqueue_head(&crc->done);
739
740 handle->crc32 = 0;
741 crc->crc32 = &handle->crc32;
742 for (thr = 0; thr < nr_threads; thr++) {
743 crc->unc[thr] = data[thr].unc;
744 crc->unc_len[thr] = &data[thr].unc_len;
745 }
746
747 crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
748 if (IS_ERR(crc->thr)) {
749 crc->thr = NULL;
750 pr_err("Cannot start CRC32 thread\n");
751 ret = -ENOMEM;
752 goto out_clean;
753 }
754
755 /*
756 * Adjust the number of required free pages after all allocations have
757 * been done. We don't want to run out of pages when writing.
758 */
759 handle->reqd_free_pages = reqd_free_pages();
760
761 pr_info("Using %u thread(s) for compression\n", nr_threads);
762 pr_info("Compressing and saving image data (%u pages)...\n",
763 nr_to_write);
764 m = nr_to_write / 10;
765 if (!m)
766 m = 1;
767 nr_pages = 0;
768 start = ktime_get();
769 for (;;) {
770 for (thr = 0; thr < nr_threads; thr++) {
771 for (off = 0; off < LZO_UNC_SIZE; off += PAGE_SIZE) {
772 ret = snapshot_read_next(snapshot);
773 if (ret < 0)
774 goto out_finish;
775
776 if (!ret)
777 break;
778
779 memcpy(data[thr].unc + off,
780 data_of(*snapshot), PAGE_SIZE);
781
782 if (!(nr_pages % m))
783 pr_info("Image saving progress: %3d%%\n",
784 nr_pages / m * 10);
785 nr_pages++;
786 }
787 if (!off)
788 break;
789
790 data[thr].unc_len = off;
791
792 atomic_set(&data[thr].ready, 1);
793 wake_up(&data[thr].go);
794 }
795
796 if (!thr)
797 break;
798
799 crc->run_threads = thr;
800 atomic_set(&crc->ready, 1);
801 wake_up(&crc->go);
802
803 for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
804 wait_event(data[thr].done,
805 atomic_read(&data[thr].stop));
806 atomic_set(&data[thr].stop, 0);
807
808 ret = data[thr].ret;
809
810 if (ret < 0) {
811 pr_err("LZO compression failed\n");
812 goto out_finish;
813 }
814
815 if (unlikely(!data[thr].cmp_len ||
816 data[thr].cmp_len >
817 lzo1x_worst_compress(data[thr].unc_len))) {
818 pr_err("Invalid LZO compressed length\n");
819 ret = -1;
820 goto out_finish;
821 }
822
823 *(size_t *)data[thr].cmp = data[thr].cmp_len;
824
825 /*
826 * Given we are writing one page at a time to disk, we
827 * copy that much from the buffer, although the last
828 * bit will likely be smaller than full page. This is
829 * OK - we saved the length of the compressed data, so
830 * any garbage at the end will be discarded when we
831 * read it.
832 */
833 for (off = 0;
834 off < LZO_HEADER + data[thr].cmp_len;
835 off += PAGE_SIZE) {
836 memcpy(page, data[thr].cmp + off, PAGE_SIZE);
837
838 ret = swap_write_page(handle, page, &hb);
839 if (ret)
840 goto out_finish;
841 }
842 }
843
844 wait_event(crc->done, atomic_read(&crc->stop));
845 atomic_set(&crc->stop, 0);
846 }
847
848out_finish:
849 err2 = hib_wait_io(&hb);
850 stop = ktime_get();
851 if (!ret)
852 ret = err2;
853 if (!ret)
854 pr_info("Image saving done\n");
855 swsusp_show_speed(start, stop, nr_to_write, "Wrote");
856out_clean:
857 if (crc) {
858 if (crc->thr)
859 kthread_stop(crc->thr);
860 kfree(crc);
861 }
862 if (data) {
863 for (thr = 0; thr < nr_threads; thr++)
864 if (data[thr].thr)
865 kthread_stop(data[thr].thr);
866 vfree(data);
867 }
868 if (page) free_page((unsigned long)page);
869
870 return ret;
871}
872
873/**
874 * enough_swap - Make sure we have enough swap to save the image.
875 *
876 * Returns TRUE or FALSE after checking the total amount of swap
877 * space avaiable from the resume partition.
878 */
879
880static int enough_swap(unsigned int nr_pages)
881{
882 unsigned int free_swap = count_swap_pages(root_swap, 1);
883 unsigned int required;
884
885 pr_debug("Free swap pages: %u\n", free_swap);
886
887 required = PAGES_FOR_IO + nr_pages;
888 return free_swap > required;
889}
890
891/**
892 * swsusp_write - Write entire image and metadata.
893 * @flags: flags to pass to the "boot" kernel in the image header
894 *
895 * It is important _NOT_ to umount filesystems at this point. We want
896 * them synced (in case something goes wrong) but we DO not want to mark
897 * filesystem clean: it is not. (And it does not matter, if we resume
898 * correctly, we'll mark system clean, anyway.)
899 */
900
901int swsusp_write(unsigned int flags)
902{
903 struct swap_map_handle handle;
904 struct snapshot_handle snapshot;
905 struct swsusp_info *header;
906 unsigned long pages;
907 int error;
908
909 pages = snapshot_get_image_size();
910 error = get_swap_writer(&handle);
911 if (error) {
912 pr_err("Cannot get swap writer\n");
913 return error;
914 }
915 if (flags & SF_NOCOMPRESS_MODE) {
916 if (!enough_swap(pages)) {
917 pr_err("Not enough free swap\n");
918 error = -ENOSPC;
919 goto out_finish;
920 }
921 }
922 memset(&snapshot, 0, sizeof(struct snapshot_handle));
923 error = snapshot_read_next(&snapshot);
924 if (error < (int)PAGE_SIZE) {
925 if (error >= 0)
926 error = -EFAULT;
927
928 goto out_finish;
929 }
930 header = (struct swsusp_info *)data_of(snapshot);
931 error = swap_write_page(&handle, header, NULL);
932 if (!error) {
933 error = (flags & SF_NOCOMPRESS_MODE) ?
934 save_image(&handle, &snapshot, pages - 1) :
935 save_image_lzo(&handle, &snapshot, pages - 1);
936 }
937out_finish:
938 error = swap_writer_finish(&handle, flags, error);
939 return error;
940}
941
942/**
943 * The following functions allow us to read data using a swap map
944 * in a file-alike way
945 */
946
947static void release_swap_reader(struct swap_map_handle *handle)
948{
949 struct swap_map_page_list *tmp;
950
951 while (handle->maps) {
952 if (handle->maps->map)
953 free_page((unsigned long)handle->maps->map);
954 tmp = handle->maps;
955 handle->maps = handle->maps->next;
956 kfree(tmp);
957 }
958 handle->cur = NULL;
959}
960
961static int get_swap_reader(struct swap_map_handle *handle,
962 unsigned int *flags_p)
963{
964 int error;
965 struct swap_map_page_list *tmp, *last;
966 sector_t offset;
967
968 *flags_p = swsusp_header->flags;
969
970 if (!swsusp_header->image) /* how can this happen? */
971 return -EINVAL;
972
973 handle->cur = NULL;
974 last = handle->maps = NULL;
975 offset = swsusp_header->image;
976 while (offset) {
977 tmp = kzalloc(sizeof(*handle->maps), GFP_KERNEL);
978 if (!tmp) {
979 release_swap_reader(handle);
980 return -ENOMEM;
981 }
982 if (!handle->maps)
983 handle->maps = tmp;
984 if (last)
985 last->next = tmp;
986 last = tmp;
987
988 tmp->map = (struct swap_map_page *)
989 __get_free_page(GFP_NOIO | __GFP_HIGH);
990 if (!tmp->map) {
991 release_swap_reader(handle);
992 return -ENOMEM;
993 }
994
995 error = hib_submit_io(REQ_OP_READ, 0, offset, tmp->map, NULL);
996 if (error) {
997 release_swap_reader(handle);
998 return error;
999 }
1000 offset = tmp->map->next_swap;
1001 }
1002 handle->k = 0;
1003 handle->cur = handle->maps->map;
1004 return 0;
1005}
1006
1007static int swap_read_page(struct swap_map_handle *handle, void *buf,
1008 struct hib_bio_batch *hb)
1009{
1010 sector_t offset;
1011 int error;
1012 struct swap_map_page_list *tmp;
1013
1014 if (!handle->cur)
1015 return -EINVAL;
1016 offset = handle->cur->entries[handle->k];
1017 if (!offset)
1018 return -EFAULT;
1019 error = hib_submit_io(REQ_OP_READ, 0, offset, buf, hb);
1020 if (error)
1021 return error;
1022 if (++handle->k >= MAP_PAGE_ENTRIES) {
1023 handle->k = 0;
1024 free_page((unsigned long)handle->maps->map);
1025 tmp = handle->maps;
1026 handle->maps = handle->maps->next;
1027 kfree(tmp);
1028 if (!handle->maps)
1029 release_swap_reader(handle);
1030 else
1031 handle->cur = handle->maps->map;
1032 }
1033 return error;
1034}
1035
1036static int swap_reader_finish(struct swap_map_handle *handle)
1037{
1038 release_swap_reader(handle);
1039
1040 return 0;
1041}
1042
1043/**
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)
1047 */
1048
1049static int load_image(struct swap_map_handle *handle,
1050 struct snapshot_handle *snapshot,
1051 unsigned int nr_to_read)
1052{
1053 unsigned int m;
1054 int ret = 0;
1055 ktime_t start;
1056 ktime_t stop;
1057 struct hib_bio_batch hb;
1058 int err2;
1059 unsigned nr_pages;
1060
1061 hib_init_batch(&hb);
1062
1063 clean_pages_on_read = true;
1064 pr_info("Loading image data pages (%u pages)...\n", nr_to_read);
1065 m = nr_to_read / 10;
1066 if (!m)
1067 m = 1;
1068 nr_pages = 0;
1069 start = ktime_get();
1070 for ( ; ; ) {
1071 ret = snapshot_write_next(snapshot);
1072 if (ret <= 0)
1073 break;
1074 ret = swap_read_page(handle, data_of(*snapshot), &hb);
1075 if (ret)
1076 break;
1077 if (snapshot->sync_read)
1078 ret = hib_wait_io(&hb);
1079 if (ret)
1080 break;
1081 if (!(nr_pages % m))
1082 pr_info("Image loading progress: %3d%%\n",
1083 nr_pages / m * 10);
1084 nr_pages++;
1085 }
1086 err2 = hib_wait_io(&hb);
1087 stop = ktime_get();
1088 if (!ret)
1089 ret = err2;
1090 if (!ret) {
1091 pr_info("Image loading done\n");
1092 snapshot_write_finalize(snapshot);
1093 if (!snapshot_image_loaded(snapshot))
1094 ret = -ENODATA;
1095 }
1096 swsusp_show_speed(start, stop, nr_to_read, "Read");
1097 return ret;
1098}
1099
1100/**
1101 * Structure used for LZO data decompression.
1102 */
1103struct dec_data {
1104 struct task_struct *thr; /* thread */
1105 atomic_t ready; /* ready to start flag */
1106 atomic_t stop; /* ready to stop flag */
1107 int ret; /* return code */
1108 wait_queue_head_t go; /* start decompression */
1109 wait_queue_head_t done; /* decompression done */
1110 size_t unc_len; /* uncompressed length */
1111 size_t cmp_len; /* compressed length */
1112 unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */
1113 unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */
1114};
1115
1116/**
1117 * Deompression function that runs in its own thread.
1118 */
1119static int lzo_decompress_threadfn(void *data)
1120{
1121 struct dec_data *d = data;
1122
1123 while (1) {
1124 wait_event(d->go, atomic_read(&d->ready) ||
1125 kthread_should_stop());
1126 if (kthread_should_stop()) {
1127 d->thr = NULL;
1128 d->ret = -1;
1129 atomic_set(&d->stop, 1);
1130 wake_up(&d->done);
1131 break;
1132 }
1133 atomic_set(&d->ready, 0);
1134
1135 d->unc_len = LZO_UNC_SIZE;
1136 d->ret = lzo1x_decompress_safe(d->cmp + LZO_HEADER, d->cmp_len,
1137 d->unc, &d->unc_len);
1138 if (clean_pages_on_decompress)
1139 flush_icache_range((unsigned long)d->unc,
1140 (unsigned long)d->unc + d->unc_len);
1141
1142 atomic_set(&d->stop, 1);
1143 wake_up(&d->done);
1144 }
1145 return 0;
1146}
1147
1148/**
1149 * load_image_lzo - Load compressed image data and decompress them with LZO.
1150 * @handle: Swap map handle to use for loading data.
1151 * @snapshot: Image to copy uncompressed data into.
1152 * @nr_to_read: Number of pages to load.
1153 */
1154static int load_image_lzo(struct swap_map_handle *handle,
1155 struct snapshot_handle *snapshot,
1156 unsigned int nr_to_read)
1157{
1158 unsigned int m;
1159 int ret = 0;
1160 int eof = 0;
1161 struct hib_bio_batch hb;
1162 ktime_t start;
1163 ktime_t stop;
1164 unsigned nr_pages;
1165 size_t off;
1166 unsigned i, thr, run_threads, nr_threads;
1167 unsigned ring = 0, pg = 0, ring_size = 0,
1168 have = 0, want, need, asked = 0;
1169 unsigned long read_pages = 0;
1170 unsigned char **page = NULL;
1171 struct dec_data *data = NULL;
1172 struct crc_data *crc = NULL;
1173
1174 hib_init_batch(&hb);
1175
1176 /*
1177 * We'll limit the number of threads for decompression to limit memory
1178 * footprint.
1179 */
1180 nr_threads = num_online_cpus() - 1;
1181 nr_threads = clamp_val(nr_threads, 1, LZO_THREADS);
1182
1183 page = vmalloc(array_size(LZO_MAX_RD_PAGES, sizeof(*page)));
1184 if (!page) {
1185 pr_err("Failed to allocate LZO page\n");
1186 ret = -ENOMEM;
1187 goto out_clean;
1188 }
1189
1190 data = vmalloc(array_size(nr_threads, sizeof(*data)));
1191 if (!data) {
1192 pr_err("Failed to allocate LZO data\n");
1193 ret = -ENOMEM;
1194 goto out_clean;
1195 }
1196 for (thr = 0; thr < nr_threads; thr++)
1197 memset(&data[thr], 0, offsetof(struct dec_data, go));
1198
1199 crc = kmalloc(sizeof(*crc), GFP_KERNEL);
1200 if (!crc) {
1201 pr_err("Failed to allocate crc\n");
1202 ret = -ENOMEM;
1203 goto out_clean;
1204 }
1205 memset(crc, 0, offsetof(struct crc_data, go));
1206
1207 clean_pages_on_decompress = true;
1208
1209 /*
1210 * Start the decompression threads.
1211 */
1212 for (thr = 0; thr < nr_threads; thr++) {
1213 init_waitqueue_head(&data[thr].go);
1214 init_waitqueue_head(&data[thr].done);
1215
1216 data[thr].thr = kthread_run(lzo_decompress_threadfn,
1217 &data[thr],
1218 "image_decompress/%u", thr);
1219 if (IS_ERR(data[thr].thr)) {
1220 data[thr].thr = NULL;
1221 pr_err("Cannot start decompression threads\n");
1222 ret = -ENOMEM;
1223 goto out_clean;
1224 }
1225 }
1226
1227 /*
1228 * Start the CRC32 thread.
1229 */
1230 init_waitqueue_head(&crc->go);
1231 init_waitqueue_head(&crc->done);
1232
1233 handle->crc32 = 0;
1234 crc->crc32 = &handle->crc32;
1235 for (thr = 0; thr < nr_threads; thr++) {
1236 crc->unc[thr] = data[thr].unc;
1237 crc->unc_len[thr] = &data[thr].unc_len;
1238 }
1239
1240 crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
1241 if (IS_ERR(crc->thr)) {
1242 crc->thr = NULL;
1243 pr_err("Cannot start CRC32 thread\n");
1244 ret = -ENOMEM;
1245 goto out_clean;
1246 }
1247
1248 /*
1249 * Set the number of pages for read buffering.
1250 * This is complete guesswork, because we'll only know the real
1251 * picture once prepare_image() is called, which is much later on
1252 * during the image load phase. We'll assume the worst case and
1253 * say that none of the image pages are from high memory.
1254 */
1255 if (low_free_pages() > snapshot_get_image_size())
1256 read_pages = (low_free_pages() - snapshot_get_image_size()) / 2;
1257 read_pages = clamp_val(read_pages, LZO_MIN_RD_PAGES, LZO_MAX_RD_PAGES);
1258
1259 for (i = 0; i < read_pages; i++) {
1260 page[i] = (void *)__get_free_page(i < LZO_CMP_PAGES ?
1261 GFP_NOIO | __GFP_HIGH :
1262 GFP_NOIO | __GFP_NOWARN |
1263 __GFP_NORETRY);
1264
1265 if (!page[i]) {
1266 if (i < LZO_CMP_PAGES) {
1267 ring_size = i;
1268 pr_err("Failed to allocate LZO pages\n");
1269 ret = -ENOMEM;
1270 goto out_clean;
1271 } else {
1272 break;
1273 }
1274 }
1275 }
1276 want = ring_size = i;
1277
1278 pr_info("Using %u thread(s) for decompression\n", nr_threads);
1279 pr_info("Loading and decompressing image data (%u pages)...\n",
1280 nr_to_read);
1281 m = nr_to_read / 10;
1282 if (!m)
1283 m = 1;
1284 nr_pages = 0;
1285 start = ktime_get();
1286
1287 ret = snapshot_write_next(snapshot);
1288 if (ret <= 0)
1289 goto out_finish;
1290
1291 for(;;) {
1292 for (i = 0; !eof && i < want; i++) {
1293 ret = swap_read_page(handle, page[ring], &hb);
1294 if (ret) {
1295 /*
1296 * On real read error, finish. On end of data,
1297 * set EOF flag and just exit the read loop.
1298 */
1299 if (handle->cur &&
1300 handle->cur->entries[handle->k]) {
1301 goto out_finish;
1302 } else {
1303 eof = 1;
1304 break;
1305 }
1306 }
1307 if (++ring >= ring_size)
1308 ring = 0;
1309 }
1310 asked += i;
1311 want -= i;
1312
1313 /*
1314 * We are out of data, wait for some more.
1315 */
1316 if (!have) {
1317 if (!asked)
1318 break;
1319
1320 ret = hib_wait_io(&hb);
1321 if (ret)
1322 goto out_finish;
1323 have += asked;
1324 asked = 0;
1325 if (eof)
1326 eof = 2;
1327 }
1328
1329 if (crc->run_threads) {
1330 wait_event(crc->done, atomic_read(&crc->stop));
1331 atomic_set(&crc->stop, 0);
1332 crc->run_threads = 0;
1333 }
1334
1335 for (thr = 0; have && thr < nr_threads; thr++) {
1336 data[thr].cmp_len = *(size_t *)page[pg];
1337 if (unlikely(!data[thr].cmp_len ||
1338 data[thr].cmp_len >
1339 lzo1x_worst_compress(LZO_UNC_SIZE))) {
1340 pr_err("Invalid LZO compressed length\n");
1341 ret = -1;
1342 goto out_finish;
1343 }
1344
1345 need = DIV_ROUND_UP(data[thr].cmp_len + LZO_HEADER,
1346 PAGE_SIZE);
1347 if (need > have) {
1348 if (eof > 1) {
1349 ret = -1;
1350 goto out_finish;
1351 }
1352 break;
1353 }
1354
1355 for (off = 0;
1356 off < LZO_HEADER + data[thr].cmp_len;
1357 off += PAGE_SIZE) {
1358 memcpy(data[thr].cmp + off,
1359 page[pg], PAGE_SIZE);
1360 have--;
1361 want++;
1362 if (++pg >= ring_size)
1363 pg = 0;
1364 }
1365
1366 atomic_set(&data[thr].ready, 1);
1367 wake_up(&data[thr].go);
1368 }
1369
1370 /*
1371 * Wait for more data while we are decompressing.
1372 */
1373 if (have < LZO_CMP_PAGES && asked) {
1374 ret = hib_wait_io(&hb);
1375 if (ret)
1376 goto out_finish;
1377 have += asked;
1378 asked = 0;
1379 if (eof)
1380 eof = 2;
1381 }
1382
1383 for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
1384 wait_event(data[thr].done,
1385 atomic_read(&data[thr].stop));
1386 atomic_set(&data[thr].stop, 0);
1387
1388 ret = data[thr].ret;
1389
1390 if (ret < 0) {
1391 pr_err("LZO decompression failed\n");
1392 goto out_finish;
1393 }
1394
1395 if (unlikely(!data[thr].unc_len ||
1396 data[thr].unc_len > LZO_UNC_SIZE ||
1397 data[thr].unc_len & (PAGE_SIZE - 1))) {
1398 pr_err("Invalid LZO uncompressed length\n");
1399 ret = -1;
1400 goto out_finish;
1401 }
1402
1403 for (off = 0;
1404 off < data[thr].unc_len; off += PAGE_SIZE) {
1405 memcpy(data_of(*snapshot),
1406 data[thr].unc + off, PAGE_SIZE);
1407
1408 if (!(nr_pages % m))
1409 pr_info("Image loading progress: %3d%%\n",
1410 nr_pages / m * 10);
1411 nr_pages++;
1412
1413 ret = snapshot_write_next(snapshot);
1414 if (ret <= 0) {
1415 crc->run_threads = thr + 1;
1416 atomic_set(&crc->ready, 1);
1417 wake_up(&crc->go);
1418 goto out_finish;
1419 }
1420 }
1421 }
1422
1423 crc->run_threads = thr;
1424 atomic_set(&crc->ready, 1);
1425 wake_up(&crc->go);
1426 }
1427
1428out_finish:
1429 if (crc->run_threads) {
1430 wait_event(crc->done, atomic_read(&crc->stop));
1431 atomic_set(&crc->stop, 0);
1432 }
1433 stop = ktime_get();
1434 if (!ret) {
1435 pr_info("Image loading done\n");
1436 snapshot_write_finalize(snapshot);
1437 if (!snapshot_image_loaded(snapshot))
1438 ret = -ENODATA;
1439 if (!ret) {
1440 if (swsusp_header->flags & SF_CRC32_MODE) {
1441 if(handle->crc32 != swsusp_header->crc32) {
1442 pr_err("Invalid image CRC32!\n");
1443 ret = -ENODATA;
1444 }
1445 }
1446 }
1447 }
1448 swsusp_show_speed(start, stop, nr_to_read, "Read");
1449out_clean:
1450 for (i = 0; i < ring_size; i++)
1451 free_page((unsigned long)page[i]);
1452 if (crc) {
1453 if (crc->thr)
1454 kthread_stop(crc->thr);
1455 kfree(crc);
1456 }
1457 if (data) {
1458 for (thr = 0; thr < nr_threads; thr++)
1459 if (data[thr].thr)
1460 kthread_stop(data[thr].thr);
1461 vfree(data);
1462 }
1463 vfree(page);
1464
1465 return ret;
1466}
1467
1468/**
1469 * swsusp_read - read the hibernation image.
1470 * @flags_p: flags passed by the "frozen" kernel in the image header should
1471 * be written into this memory location
1472 */
1473
1474int swsusp_read(unsigned int *flags_p)
1475{
1476 int error;
1477 struct swap_map_handle handle;
1478 struct snapshot_handle snapshot;
1479 struct swsusp_info *header;
1480
1481 memset(&snapshot, 0, sizeof(struct snapshot_handle));
1482 error = snapshot_write_next(&snapshot);
1483 if (error < (int)PAGE_SIZE)
1484 return error < 0 ? error : -EFAULT;
1485 header = (struct swsusp_info *)data_of(snapshot);
1486 error = get_swap_reader(&handle, flags_p);
1487 if (error)
1488 goto end;
1489 if (!error)
1490 error = swap_read_page(&handle, header, NULL);
1491 if (!error) {
1492 error = (*flags_p & SF_NOCOMPRESS_MODE) ?
1493 load_image(&handle, &snapshot, header->pages - 1) :
1494 load_image_lzo(&handle, &snapshot, header->pages - 1);
1495 }
1496 swap_reader_finish(&handle);
1497end:
1498 if (!error)
1499 pr_debug("Image successfully loaded\n");
1500 else
1501 pr_debug("Error %d resuming\n", error);
1502 return error;
1503}
1504
1505/**
1506 * swsusp_check - Check for swsusp signature in the resume device
1507 */
1508
1509int swsusp_check(void)
1510{
1511 int error;
1512
1513 hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device,
1514 FMODE_READ, NULL);
1515 if (!IS_ERR(hib_resume_bdev)) {
1516 set_blocksize(hib_resume_bdev, PAGE_SIZE);
1517 clear_page(swsusp_header);
1518 error = hib_submit_io(REQ_OP_READ, 0,
1519 swsusp_resume_block,
1520 swsusp_header, NULL);
1521 if (error)
1522 goto put;
1523
1524 if (!memcmp(HIBERNATE_SIG, swsusp_header->sig, 10)) {
1525 memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10);
1526 /* Reset swap signature now */
1527 error = hib_submit_io(REQ_OP_WRITE, REQ_SYNC,
1528 swsusp_resume_block,
1529 swsusp_header, NULL);
1530 } else {
1531 error = -EINVAL;
1532 }
1533
1534put:
1535 if (error)
1536 blkdev_put(hib_resume_bdev, FMODE_READ);
1537 else
1538 pr_debug("Image signature found, resuming\n");
1539 } else {
1540 error = PTR_ERR(hib_resume_bdev);
1541 }
1542
1543 if (error)
1544 pr_debug("Image not found (code %d)\n", error);
1545
1546 return error;
1547}
1548
1549/**
1550 * swsusp_close - close swap device.
1551 */
1552
1553void swsusp_close(fmode_t mode)
1554{
1555 if (IS_ERR(hib_resume_bdev)) {
1556 pr_debug("Image device not initialised\n");
1557 return;
1558 }
1559
1560 blkdev_put(hib_resume_bdev, mode);
1561}
1562
1563/**
1564 * swsusp_unmark - Unmark swsusp signature in the resume device
1565 */
1566
1567#ifdef CONFIG_SUSPEND
1568int swsusp_unmark(void)
1569{
1570 int error;
1571
1572 hib_submit_io(REQ_OP_READ, 0, swsusp_resume_block,
1573 swsusp_header, NULL);
1574 if (!memcmp(HIBERNATE_SIG,swsusp_header->sig, 10)) {
1575 memcpy(swsusp_header->sig,swsusp_header->orig_sig, 10);
1576 error = hib_submit_io(REQ_OP_WRITE, REQ_SYNC,
1577 swsusp_resume_block,
1578 swsusp_header, NULL);
1579 } else {
1580 pr_err("Cannot find swsusp signature!\n");
1581 error = -ENODEV;
1582 }
1583
1584 /*
1585 * We just returned from suspend, we don't need the image any more.
1586 */
1587 free_all_swap_pages(root_swap);
1588
1589 return error;
1590}
1591#endif
1592
1593static int __init swsusp_header_init(void)
1594{
1595 swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);
1596 if (!swsusp_header)
1597 panic("Could not allocate memory for swsusp_header\n");
1598 return 0;
1599}
1600
1601core_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);