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 <crypto/acompress.h>
16#include <linux/module.h>
17#include <linux/file.h>
18#include <linux/delay.h>
19#include <linux/bitops.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/vmalloc.h>
28#include <linux/cpumask.h>
29#include <linux/atomic.h>
30#include <linux/kthread.h>
31#include <linux/crc32.h>
32#include <linux/ktime.h>
33
34#include "power.h"
35
36#define HIBERNATE_SIG "S1SUSPEND"
37
38u32 swsusp_hardware_signature;
39
40/*
41 * When reading an {un,}compressed image, we may restore pages in place,
42 * in which case some architectures need these pages cleaning before they
43 * can be executed. We don't know which pages these may be, so clean the lot.
44 */
45static bool clean_pages_on_read;
46static bool clean_pages_on_decompress;
47
48/*
49 * The swap map is a data structure used for keeping track of each page
50 * written to a swap partition. It consists of many swap_map_page
51 * structures that contain each an array of MAP_PAGE_ENTRIES swap entries.
52 * These structures are stored on the swap and linked together with the
53 * help of the .next_swap member.
54 *
55 * The swap map is created during suspend. The swap map pages are
56 * allocated and populated one at a time, so we only need one memory
57 * page to set up the entire structure.
58 *
59 * During resume we pick up all swap_map_page structures into a list.
60 */
61
62#define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(sector_t) - 1)
63
64/*
65 * Number of free pages that are not high.
66 */
67static inline unsigned long low_free_pages(void)
68{
69 return nr_free_pages() - nr_free_highpages();
70}
71
72/*
73 * Number of pages required to be kept free while writing the image. Always
74 * half of all available low pages before the writing starts.
75 */
76static inline unsigned long reqd_free_pages(void)
77{
78 return low_free_pages() / 2;
79}
80
81struct swap_map_page {
82 sector_t entries[MAP_PAGE_ENTRIES];
83 sector_t next_swap;
84};
85
86struct swap_map_page_list {
87 struct swap_map_page *map;
88 struct swap_map_page_list *next;
89};
90
91/*
92 * The swap_map_handle structure is used for handling swap in
93 * a file-alike way
94 */
95
96struct swap_map_handle {
97 struct swap_map_page *cur;
98 struct swap_map_page_list *maps;
99 sector_t cur_swap;
100 sector_t first_sector;
101 unsigned int k;
102 unsigned long reqd_free_pages;
103 u32 crc32;
104};
105
106struct swsusp_header {
107 char reserved[PAGE_SIZE - 20 - sizeof(sector_t) - sizeof(int) -
108 sizeof(u32) - sizeof(u32)];
109 u32 hw_sig;
110 u32 crc32;
111 sector_t image;
112 unsigned int flags; /* Flags to pass to the "boot" kernel */
113 char orig_sig[10];
114 char sig[10];
115} __packed;
116
117static struct swsusp_header *swsusp_header;
118
119/*
120 * The following functions are used for tracing the allocated
121 * swap pages, so that they can be freed in case of an error.
122 */
123
124struct swsusp_extent {
125 struct rb_node node;
126 unsigned long start;
127 unsigned long end;
128};
129
130static struct rb_root swsusp_extents = RB_ROOT;
131
132static int swsusp_extents_insert(unsigned long swap_offset)
133{
134 struct rb_node **new = &(swsusp_extents.rb_node);
135 struct rb_node *parent = NULL;
136 struct swsusp_extent *ext;
137
138 /* Figure out where to put the new node */
139 while (*new) {
140 ext = rb_entry(*new, struct swsusp_extent, node);
141 parent = *new;
142 if (swap_offset < ext->start) {
143 /* Try to merge */
144 if (swap_offset == ext->start - 1) {
145 ext->start--;
146 return 0;
147 }
148 new = &((*new)->rb_left);
149 } else if (swap_offset > ext->end) {
150 /* Try to merge */
151 if (swap_offset == ext->end + 1) {
152 ext->end++;
153 return 0;
154 }
155 new = &((*new)->rb_right);
156 } else {
157 /* It already is in the tree */
158 return -EINVAL;
159 }
160 }
161 /* Add the new node and rebalance the tree. */
162 ext = kzalloc(sizeof(struct swsusp_extent), GFP_KERNEL);
163 if (!ext)
164 return -ENOMEM;
165
166 ext->start = swap_offset;
167 ext->end = swap_offset;
168 rb_link_node(node: &ext->node, parent, rb_link: new);
169 rb_insert_color(&ext->node, &swsusp_extents);
170 return 0;
171}
172
173/*
174 * alloc_swapdev_block - allocate a swap page and register that it has
175 * been allocated, so that it can be freed in case of an error.
176 */
177
178sector_t alloc_swapdev_block(int swap)
179{
180 unsigned long offset;
181
182 offset = swp_offset(entry: get_swap_page_of_type(swap));
183 if (offset) {
184 if (swsusp_extents_insert(swap_offset: offset))
185 swap_free(entry: swp_entry(type: swap, offset));
186 else
187 return swapdev_block(swap, offset);
188 }
189 return 0;
190}
191
192/*
193 * free_all_swap_pages - free swap pages allocated for saving image data.
194 * It also frees the extents used to register which swap entries had been
195 * allocated.
196 */
197
198void free_all_swap_pages(int swap)
199{
200 struct rb_node *node;
201
202 while ((node = swsusp_extents.rb_node)) {
203 struct swsusp_extent *ext;
204
205 ext = rb_entry(node, struct swsusp_extent, node);
206 rb_erase(node, &swsusp_extents);
207 swap_free_nr(entry: swp_entry(type: swap, offset: ext->start),
208 nr_pages: ext->end - ext->start + 1);
209
210 kfree(objp: ext);
211 }
212}
213
214int swsusp_swap_in_use(void)
215{
216 return (swsusp_extents.rb_node != NULL);
217}
218
219/*
220 * General things
221 */
222
223static unsigned short root_swap = 0xffff;
224static struct file *hib_resume_bdev_file;
225
226struct hib_bio_batch {
227 atomic_t count;
228 wait_queue_head_t wait;
229 blk_status_t error;
230 struct blk_plug plug;
231};
232
233static void hib_init_batch(struct hib_bio_batch *hb)
234{
235 atomic_set(v: &hb->count, i: 0);
236 init_waitqueue_head(&hb->wait);
237 hb->error = BLK_STS_OK;
238 blk_start_plug(&hb->plug);
239}
240
241static void hib_finish_batch(struct hib_bio_batch *hb)
242{
243 blk_finish_plug(&hb->plug);
244}
245
246static void hib_end_io(struct bio *bio)
247{
248 struct hib_bio_batch *hb = bio->bi_private;
249 struct page *page = bio_first_page_all(bio);
250
251 if (bio->bi_status) {
252 pr_alert("Read-error on swap-device (%u:%u:%Lu)\n",
253 MAJOR(bio_dev(bio)), MINOR(bio_dev(bio)),
254 (unsigned long long)bio->bi_iter.bi_sector);
255 }
256
257 if (bio_data_dir(bio) == WRITE)
258 put_page(page);
259 else if (clean_pages_on_read)
260 flush_icache_range(start: (unsigned long)page_address(page),
261 end: (unsigned long)page_address(page) + PAGE_SIZE);
262
263 if (bio->bi_status && !hb->error)
264 hb->error = bio->bi_status;
265 if (atomic_dec_and_test(v: &hb->count))
266 wake_up(&hb->wait);
267
268 bio_put(bio);
269}
270
271static int hib_submit_io_sync(blk_opf_t opf, pgoff_t page_off, void *addr)
272{
273 return bdev_rw_virt(bdev: file_bdev(bdev_file: hib_resume_bdev_file),
274 sector: page_off * (PAGE_SIZE >> 9), data: addr, PAGE_SIZE, op: opf);
275}
276
277static int hib_submit_io_async(blk_opf_t opf, pgoff_t page_off, void *addr,
278 struct hib_bio_batch *hb)
279{
280 struct bio *bio;
281
282 bio = bio_alloc(bdev: file_bdev(bdev_file: hib_resume_bdev_file), nr_vecs: 1, opf,
283 GFP_NOIO | __GFP_HIGH);
284 bio->bi_iter.bi_sector = page_off * (PAGE_SIZE >> 9);
285 bio_add_virt_nofail(bio, vaddr: addr, PAGE_SIZE);
286 bio->bi_end_io = hib_end_io;
287 bio->bi_private = hb;
288 atomic_inc(v: &hb->count);
289 submit_bio(bio);
290 return 0;
291}
292
293static int hib_wait_io(struct hib_bio_batch *hb)
294{
295 /*
296 * We are relying on the behavior of blk_plug that a thread with
297 * a plug will flush the plug list before sleeping.
298 */
299 wait_event(hb->wait, atomic_read(&hb->count) == 0);
300 return blk_status_to_errno(status: hb->error);
301}
302
303/*
304 * Saving part
305 */
306static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
307{
308 int error;
309
310 hib_submit_io_sync(opf: REQ_OP_READ, page_off: swsusp_resume_block, addr: swsusp_header);
311 if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||
312 !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {
313 memcpy(to: swsusp_header->orig_sig,from: swsusp_header->sig, len: 10);
314 memcpy(to: swsusp_header->sig, HIBERNATE_SIG, len: 10);
315 swsusp_header->image = handle->first_sector;
316 if (swsusp_hardware_signature) {
317 swsusp_header->hw_sig = swsusp_hardware_signature;
318 flags |= SF_HW_SIG;
319 }
320 swsusp_header->flags = flags;
321 if (flags & SF_CRC32_MODE)
322 swsusp_header->crc32 = handle->crc32;
323 error = hib_submit_io_sync(opf: REQ_OP_WRITE | REQ_SYNC,
324 page_off: swsusp_resume_block, addr: swsusp_header);
325 } else {
326 pr_err("Swap header not found!\n");
327 error = -ENODEV;
328 }
329 return error;
330}
331
332/*
333 * Hold the swsusp_header flag. This is used in software_resume() in
334 * 'kernel/power/hibernate' to check if the image is compressed and query
335 * for the compression algorithm support(if so).
336 */
337unsigned int swsusp_header_flags;
338
339/**
340 * swsusp_swap_check - check if the resume device is a swap device
341 * and get its index (if so)
342 *
343 * This is called before saving image
344 */
345static int swsusp_swap_check(void)
346{
347 int res;
348
349 if (swsusp_resume_device)
350 res = swap_type_of(device: swsusp_resume_device, offset: swsusp_resume_block);
351 else
352 res = find_first_swap(device: &swsusp_resume_device);
353 if (res < 0)
354 return res;
355 root_swap = res;
356
357 hib_resume_bdev_file = bdev_file_open_by_dev(dev: swsusp_resume_device,
358 BLK_OPEN_WRITE, NULL, NULL);
359 if (IS_ERR(ptr: hib_resume_bdev_file))
360 return PTR_ERR(ptr: hib_resume_bdev_file);
361
362 return 0;
363}
364
365/**
366 * write_page - Write one page to given swap location.
367 * @buf: Address we're writing.
368 * @offset: Offset of the swap page we're writing to.
369 * @hb: bio completion batch
370 */
371
372static int write_page(void *buf, sector_t offset, struct hib_bio_batch *hb)
373{
374 gfp_t gfp = GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY;
375 void *src;
376 int ret;
377
378 if (!offset)
379 return -ENOSPC;
380
381 if (!hb)
382 goto sync_io;
383
384 src = (void *)__get_free_page(gfp);
385 if (!src) {
386 ret = hib_wait_io(hb); /* Free pages */
387 if (ret)
388 return ret;
389 src = (void *)__get_free_page(gfp);
390 if (WARN_ON_ONCE(!src))
391 goto sync_io;
392 }
393
394 copy_page(to: src, from: buf);
395 return hib_submit_io_async(opf: REQ_OP_WRITE | REQ_SYNC, page_off: offset, addr: src, hb);
396sync_io:
397 return hib_submit_io_sync(opf: REQ_OP_WRITE | REQ_SYNC, page_off: offset, addr: buf);
398}
399
400static void release_swap_writer(struct swap_map_handle *handle)
401{
402 if (handle->cur)
403 free_page((unsigned long)handle->cur);
404 handle->cur = NULL;
405}
406
407static int get_swap_writer(struct swap_map_handle *handle)
408{
409 int ret;
410
411 ret = swsusp_swap_check();
412 if (ret) {
413 if (ret != -ENOSPC)
414 pr_err("Cannot find swap device, try swapon -a\n");
415 return ret;
416 }
417 handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL);
418 if (!handle->cur) {
419 ret = -ENOMEM;
420 goto err_close;
421 }
422 handle->cur_swap = alloc_swapdev_block(swap: root_swap);
423 if (!handle->cur_swap) {
424 ret = -ENOSPC;
425 goto err_rel;
426 }
427 handle->k = 0;
428 handle->reqd_free_pages = reqd_free_pages();
429 handle->first_sector = handle->cur_swap;
430 return 0;
431err_rel:
432 release_swap_writer(handle);
433err_close:
434 swsusp_close();
435 return ret;
436}
437
438static int swap_write_page(struct swap_map_handle *handle, void *buf,
439 struct hib_bio_batch *hb)
440{
441 int error;
442 sector_t offset;
443
444 if (!handle->cur)
445 return -EINVAL;
446 offset = alloc_swapdev_block(swap: root_swap);
447 error = write_page(buf, offset, hb);
448 if (error)
449 return error;
450 handle->cur->entries[handle->k++] = offset;
451 if (handle->k >= MAP_PAGE_ENTRIES) {
452 offset = alloc_swapdev_block(swap: root_swap);
453 if (!offset)
454 return -ENOSPC;
455 handle->cur->next_swap = offset;
456 error = write_page(buf: handle->cur, offset: handle->cur_swap, hb);
457 if (error)
458 goto out;
459 clear_page(page: handle->cur);
460 handle->cur_swap = offset;
461 handle->k = 0;
462
463 if (hb && low_free_pages() <= handle->reqd_free_pages) {
464 error = hib_wait_io(hb);
465 if (error)
466 goto out;
467 /*
468 * Recalculate the number of required free pages, to
469 * make sure we never take more than half.
470 */
471 handle->reqd_free_pages = reqd_free_pages();
472 }
473 }
474 out:
475 return error;
476}
477
478static int flush_swap_writer(struct swap_map_handle *handle)
479{
480 if (handle->cur && handle->cur_swap)
481 return write_page(buf: handle->cur, offset: handle->cur_swap, NULL);
482 else
483 return -EINVAL;
484}
485
486static int swap_writer_finish(struct swap_map_handle *handle,
487 unsigned int flags, int error)
488{
489 if (!error) {
490 pr_info("S");
491 error = mark_swapfiles(handle, flags);
492 pr_cont("|\n");
493 flush_swap_writer(handle);
494 }
495
496 if (error)
497 free_all_swap_pages(swap: root_swap);
498 release_swap_writer(handle);
499 swsusp_close();
500
501 return error;
502}
503
504/*
505 * Bytes we need for compressed data in worst case. We assume(limitation)
506 * this is the worst of all the compression algorithms.
507 */
508#define bytes_worst_compress(x) ((x) + ((x) / 16) + 64 + 3 + 2)
509
510/* We need to remember how much compressed data we need to read. */
511#define CMP_HEADER sizeof(size_t)
512
513/* Number of pages/bytes we'll compress at one time. */
514#define UNC_PAGES 32
515#define UNC_SIZE (UNC_PAGES * PAGE_SIZE)
516
517/* Number of pages we need for compressed data (worst case). */
518#define CMP_PAGES DIV_ROUND_UP(bytes_worst_compress(UNC_SIZE) + \
519 CMP_HEADER, PAGE_SIZE)
520#define CMP_SIZE (CMP_PAGES * PAGE_SIZE)
521
522/* Maximum number of threads for compression/decompression. */
523#define CMP_THREADS 3
524
525/* Minimum/maximum number of pages for read buffering. */
526#define CMP_MIN_RD_PAGES 1024
527#define CMP_MAX_RD_PAGES 8192
528
529/**
530 * save_image - save the suspend image data
531 */
532
533static int save_image(struct swap_map_handle *handle,
534 struct snapshot_handle *snapshot,
535 unsigned int nr_to_write)
536{
537 unsigned int m;
538 int ret;
539 int nr_pages;
540 int err2;
541 struct hib_bio_batch hb;
542 ktime_t start;
543 ktime_t stop;
544
545 hib_init_batch(hb: &hb);
546
547 pr_info("Saving image data pages (%u pages)...\n",
548 nr_to_write);
549 m = nr_to_write / 10;
550 if (!m)
551 m = 1;
552 nr_pages = 0;
553 start = ktime_get();
554 while (1) {
555 ret = snapshot_read_next(handle: snapshot);
556 if (ret <= 0)
557 break;
558 ret = swap_write_page(handle, data_of(*snapshot), hb: &hb);
559 if (ret)
560 break;
561 if (!(nr_pages % m))
562 pr_info("Image saving progress: %3d%%\n",
563 nr_pages / m * 10);
564 nr_pages++;
565 }
566 err2 = hib_wait_io(hb: &hb);
567 hib_finish_batch(hb: &hb);
568 stop = ktime_get();
569 if (!ret)
570 ret = err2;
571 if (!ret)
572 pr_info("Image saving done\n");
573 swsusp_show_speed(start, stop, nr_to_write, "Wrote");
574 return ret;
575}
576
577/*
578 * Structure used for CRC32.
579 */
580struct crc_data {
581 struct task_struct *thr; /* thread */
582 atomic_t ready; /* ready to start flag */
583 atomic_t stop; /* ready to stop flag */
584 unsigned run_threads; /* nr current threads */
585 wait_queue_head_t go; /* start crc update */
586 wait_queue_head_t done; /* crc update done */
587 u32 *crc32; /* points to handle's crc32 */
588 size_t *unc_len[CMP_THREADS]; /* uncompressed lengths */
589 unsigned char *unc[CMP_THREADS]; /* uncompressed data */
590};
591
592/*
593 * CRC32 update function that runs in its own thread.
594 */
595static int crc32_threadfn(void *data)
596{
597 struct crc_data *d = data;
598 unsigned i;
599
600 while (1) {
601 wait_event(d->go, atomic_read_acquire(&d->ready) ||
602 kthread_should_stop());
603 if (kthread_should_stop()) {
604 d->thr = NULL;
605 atomic_set_release(v: &d->stop, i: 1);
606 wake_up(&d->done);
607 break;
608 }
609 atomic_set(v: &d->ready, i: 0);
610
611 for (i = 0; i < d->run_threads; i++)
612 *d->crc32 = crc32_le(crc: *d->crc32,
613 p: d->unc[i], len: *d->unc_len[i]);
614 atomic_set_release(v: &d->stop, i: 1);
615 wake_up(&d->done);
616 }
617 return 0;
618}
619/*
620 * Structure used for data compression.
621 */
622struct cmp_data {
623 struct task_struct *thr; /* thread */
624 struct crypto_acomp *cc; /* crypto compressor */
625 struct acomp_req *cr; /* crypto request */
626 atomic_t ready; /* ready to start flag */
627 atomic_t stop; /* ready to stop flag */
628 int ret; /* return code */
629 wait_queue_head_t go; /* start compression */
630 wait_queue_head_t done; /* compression done */
631 size_t unc_len; /* uncompressed length */
632 size_t cmp_len; /* compressed length */
633 unsigned char unc[UNC_SIZE]; /* uncompressed buffer */
634 unsigned char cmp[CMP_SIZE]; /* compressed buffer */
635};
636
637/* Indicates the image size after compression */
638static atomic_t compressed_size = ATOMIC_INIT(0);
639
640/*
641 * Compression function that runs in its own thread.
642 */
643static int compress_threadfn(void *data)
644{
645 struct cmp_data *d = data;
646
647 while (1) {
648 wait_event(d->go, atomic_read_acquire(&d->ready) ||
649 kthread_should_stop());
650 if (kthread_should_stop()) {
651 d->thr = NULL;
652 d->ret = -1;
653 atomic_set_release(v: &d->stop, i: 1);
654 wake_up(&d->done);
655 break;
656 }
657 atomic_set(v: &d->ready, i: 0);
658
659 acomp_request_set_callback(req: d->cr, CRYPTO_TFM_REQ_MAY_SLEEP,
660 NULL, NULL);
661 acomp_request_set_src_nondma(req: d->cr, src: d->unc, slen: d->unc_len);
662 acomp_request_set_dst_nondma(req: d->cr, dst: d->cmp + CMP_HEADER,
663 CMP_SIZE - CMP_HEADER);
664 d->ret = crypto_acomp_compress(req: d->cr);
665 d->cmp_len = d->cr->dlen;
666
667 atomic_set(v: &compressed_size, i: atomic_read(v: &compressed_size) + d->cmp_len);
668 atomic_set_release(v: &d->stop, i: 1);
669 wake_up(&d->done);
670 }
671 return 0;
672}
673
674/**
675 * save_compressed_image - Save the suspend image data after compression.
676 * @handle: Swap map handle to use for saving the image.
677 * @snapshot: Image to read data from.
678 * @nr_to_write: Number of pages to save.
679 */
680static int save_compressed_image(struct swap_map_handle *handle,
681 struct snapshot_handle *snapshot,
682 unsigned int nr_to_write)
683{
684 unsigned int m;
685 int ret = 0;
686 int nr_pages;
687 int err2;
688 struct hib_bio_batch hb;
689 ktime_t start;
690 ktime_t stop;
691 size_t off;
692 unsigned thr, run_threads, nr_threads;
693 unsigned char *page = NULL;
694 struct cmp_data *data = NULL;
695 struct crc_data *crc = NULL;
696
697 hib_init_batch(hb: &hb);
698
699 atomic_set(v: &compressed_size, i: 0);
700
701 /*
702 * We'll limit the number of threads for compression to limit memory
703 * footprint.
704 */
705 nr_threads = num_online_cpus() - 1;
706 nr_threads = clamp_val(nr_threads, 1, CMP_THREADS);
707
708 page = (void *)__get_free_page(GFP_NOIO | __GFP_HIGH);
709 if (!page) {
710 pr_err("Failed to allocate %s page\n", hib_comp_algo);
711 ret = -ENOMEM;
712 goto out_clean;
713 }
714
715 data = vcalloc(nr_threads, sizeof(*data));
716 if (!data) {
717 pr_err("Failed to allocate %s data\n", hib_comp_algo);
718 ret = -ENOMEM;
719 goto out_clean;
720 }
721
722 crc = kzalloc(sizeof(*crc), GFP_KERNEL);
723 if (!crc) {
724 pr_err("Failed to allocate crc\n");
725 ret = -ENOMEM;
726 goto out_clean;
727 }
728
729 /*
730 * Start the compression threads.
731 */
732 for (thr = 0; thr < nr_threads; thr++) {
733 init_waitqueue_head(&data[thr].go);
734 init_waitqueue_head(&data[thr].done);
735
736 data[thr].cc = crypto_alloc_acomp(alg_name: hib_comp_algo, type: 0, CRYPTO_ALG_ASYNC);
737 if (IS_ERR_OR_NULL(ptr: data[thr].cc)) {
738 pr_err("Could not allocate comp stream %ld\n", PTR_ERR(data[thr].cc));
739 ret = -EFAULT;
740 goto out_clean;
741 }
742
743 data[thr].cr = acomp_request_alloc(data[thr].cc);
744 if (!data[thr].cr) {
745 pr_err("Could not allocate comp request\n");
746 ret = -ENOMEM;
747 goto out_clean;
748 }
749
750 data[thr].thr = kthread_run(compress_threadfn,
751 &data[thr],
752 "image_compress/%u", thr);
753 if (IS_ERR(ptr: data[thr].thr)) {
754 data[thr].thr = NULL;
755 pr_err("Cannot start compression threads\n");
756 ret = -ENOMEM;
757 goto out_clean;
758 }
759 }
760
761 /*
762 * Start the CRC32 thread.
763 */
764 init_waitqueue_head(&crc->go);
765 init_waitqueue_head(&crc->done);
766
767 handle->crc32 = 0;
768 crc->crc32 = &handle->crc32;
769 for (thr = 0; thr < nr_threads; thr++) {
770 crc->unc[thr] = data[thr].unc;
771 crc->unc_len[thr] = &data[thr].unc_len;
772 }
773
774 crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
775 if (IS_ERR(ptr: crc->thr)) {
776 crc->thr = NULL;
777 pr_err("Cannot start CRC32 thread\n");
778 ret = -ENOMEM;
779 goto out_clean;
780 }
781
782 /*
783 * Adjust the number of required free pages after all allocations have
784 * been done. We don't want to run out of pages when writing.
785 */
786 handle->reqd_free_pages = reqd_free_pages();
787
788 pr_info("Using %u thread(s) for %s compression\n", nr_threads, hib_comp_algo);
789 pr_info("Compressing and saving image data (%u pages)...\n",
790 nr_to_write);
791 m = nr_to_write / 10;
792 if (!m)
793 m = 1;
794 nr_pages = 0;
795 start = ktime_get();
796 for (;;) {
797 for (thr = 0; thr < nr_threads; thr++) {
798 for (off = 0; off < UNC_SIZE; off += PAGE_SIZE) {
799 ret = snapshot_read_next(handle: snapshot);
800 if (ret < 0)
801 goto out_finish;
802
803 if (!ret)
804 break;
805
806 memcpy(to: data[thr].unc + off,
807 data_of(*snapshot), PAGE_SIZE);
808
809 if (!(nr_pages % m))
810 pr_info("Image saving progress: %3d%%\n",
811 nr_pages / m * 10);
812 nr_pages++;
813 }
814 if (!off)
815 break;
816
817 data[thr].unc_len = off;
818
819 atomic_set_release(v: &data[thr].ready, i: 1);
820 wake_up(&data[thr].go);
821 }
822
823 if (!thr)
824 break;
825
826 crc->run_threads = thr;
827 atomic_set_release(v: &crc->ready, i: 1);
828 wake_up(&crc->go);
829
830 for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
831 wait_event(data[thr].done,
832 atomic_read_acquire(&data[thr].stop));
833 atomic_set(v: &data[thr].stop, i: 0);
834
835 ret = data[thr].ret;
836
837 if (ret < 0) {
838 pr_err("%s compression failed\n", hib_comp_algo);
839 goto out_finish;
840 }
841
842 if (unlikely(!data[thr].cmp_len ||
843 data[thr].cmp_len >
844 bytes_worst_compress(data[thr].unc_len))) {
845 pr_err("Invalid %s compressed length\n", hib_comp_algo);
846 ret = -1;
847 goto out_finish;
848 }
849
850 *(size_t *)data[thr].cmp = data[thr].cmp_len;
851
852 /*
853 * Given we are writing one page at a time to disk, we
854 * copy that much from the buffer, although the last
855 * bit will likely be smaller than full page. This is
856 * OK - we saved the length of the compressed data, so
857 * any garbage at the end will be discarded when we
858 * read it.
859 */
860 for (off = 0;
861 off < CMP_HEADER + data[thr].cmp_len;
862 off += PAGE_SIZE) {
863 memcpy(to: page, from: data[thr].cmp + off, PAGE_SIZE);
864
865 ret = swap_write_page(handle, buf: page, hb: &hb);
866 if (ret)
867 goto out_finish;
868 }
869 }
870
871 wait_event(crc->done, atomic_read_acquire(&crc->stop));
872 atomic_set(v: &crc->stop, i: 0);
873 }
874
875out_finish:
876 err2 = hib_wait_io(hb: &hb);
877 stop = ktime_get();
878 if (!ret)
879 ret = err2;
880 if (!ret)
881 pr_info("Image saving done\n");
882 swsusp_show_speed(start, stop, nr_to_write, "Wrote");
883 pr_info("Image size after compression: %d kbytes\n",
884 (atomic_read(&compressed_size) / 1024));
885
886out_clean:
887 hib_finish_batch(hb: &hb);
888 if (crc) {
889 if (crc->thr)
890 kthread_stop(k: crc->thr);
891 kfree(objp: crc);
892 }
893 if (data) {
894 for (thr = 0; thr < nr_threads; thr++) {
895 if (data[thr].thr)
896 kthread_stop(k: data[thr].thr);
897 acomp_request_free(req: data[thr].cr);
898 crypto_free_acomp(tfm: data[thr].cc);
899 }
900 vfree(addr: data);
901 }
902 if (page) free_page((unsigned long)page);
903
904 return ret;
905}
906
907/**
908 * enough_swap - Make sure we have enough swap to save the image.
909 *
910 * Returns TRUE or FALSE after checking the total amount of swap
911 * space available from the resume partition.
912 */
913
914static int enough_swap(unsigned int nr_pages)
915{
916 unsigned int free_swap = count_swap_pages(root_swap, 1);
917 unsigned int required;
918
919 pr_debug("Free swap pages: %u\n", free_swap);
920
921 required = PAGES_FOR_IO + nr_pages;
922 return free_swap > required;
923}
924
925/**
926 * swsusp_write - Write entire image and metadata.
927 * @flags: flags to pass to the "boot" kernel in the image header
928 *
929 * It is important _NOT_ to umount filesystems at this point. We want
930 * them synced (in case something goes wrong) but we DO not want to mark
931 * filesystem clean: it is not. (And it does not matter, if we resume
932 * correctly, we'll mark system clean, anyway.)
933 */
934
935int swsusp_write(unsigned int flags)
936{
937 struct swap_map_handle handle;
938 struct snapshot_handle snapshot;
939 struct swsusp_info *header;
940 unsigned long pages;
941 int error;
942
943 pages = snapshot_get_image_size();
944 error = get_swap_writer(handle: &handle);
945 if (error) {
946 pr_err("Cannot get swap writer\n");
947 return error;
948 }
949 if (flags & SF_NOCOMPRESS_MODE) {
950 if (!enough_swap(nr_pages: pages)) {
951 pr_err("Not enough free swap\n");
952 error = -ENOSPC;
953 goto out_finish;
954 }
955 }
956 memset(s: &snapshot, c: 0, n: sizeof(struct snapshot_handle));
957 error = snapshot_read_next(handle: &snapshot);
958 if (error < (int)PAGE_SIZE) {
959 if (error >= 0)
960 error = -EFAULT;
961
962 goto out_finish;
963 }
964 header = (struct swsusp_info *)data_of(snapshot);
965 error = swap_write_page(handle: &handle, buf: header, NULL);
966 if (!error) {
967 error = (flags & SF_NOCOMPRESS_MODE) ?
968 save_image(handle: &handle, snapshot: &snapshot, nr_to_write: pages - 1) :
969 save_compressed_image(handle: &handle, snapshot: &snapshot, nr_to_write: pages - 1);
970 }
971out_finish:
972 error = swap_writer_finish(handle: &handle, flags, error);
973 return error;
974}
975
976/*
977 * The following functions allow us to read data using a swap map
978 * in a file-like way.
979 */
980
981static void release_swap_reader(struct swap_map_handle *handle)
982{
983 struct swap_map_page_list *tmp;
984
985 while (handle->maps) {
986 if (handle->maps->map)
987 free_page((unsigned long)handle->maps->map);
988 tmp = handle->maps;
989 handle->maps = handle->maps->next;
990 kfree(objp: tmp);
991 }
992 handle->cur = NULL;
993}
994
995static int get_swap_reader(struct swap_map_handle *handle,
996 unsigned int *flags_p)
997{
998 int error;
999 struct swap_map_page_list *tmp, *last;
1000 sector_t offset;
1001
1002 *flags_p = swsusp_header->flags;
1003
1004 if (!swsusp_header->image) /* how can this happen? */
1005 return -EINVAL;
1006
1007 handle->cur = NULL;
1008 last = handle->maps = NULL;
1009 offset = swsusp_header->image;
1010 while (offset) {
1011 tmp = kzalloc(sizeof(*handle->maps), GFP_KERNEL);
1012 if (!tmp) {
1013 release_swap_reader(handle);
1014 return -ENOMEM;
1015 }
1016 if (!handle->maps)
1017 handle->maps = tmp;
1018 if (last)
1019 last->next = tmp;
1020 last = tmp;
1021
1022 tmp->map = (struct swap_map_page *)
1023 __get_free_page(GFP_NOIO | __GFP_HIGH);
1024 if (!tmp->map) {
1025 release_swap_reader(handle);
1026 return -ENOMEM;
1027 }
1028
1029 error = hib_submit_io_sync(opf: REQ_OP_READ, page_off: offset, addr: tmp->map);
1030 if (error) {
1031 release_swap_reader(handle);
1032 return error;
1033 }
1034 offset = tmp->map->next_swap;
1035 }
1036 handle->k = 0;
1037 handle->cur = handle->maps->map;
1038 return 0;
1039}
1040
1041static int swap_read_page(struct swap_map_handle *handle, void *buf,
1042 struct hib_bio_batch *hb)
1043{
1044 sector_t offset;
1045 int error;
1046 struct swap_map_page_list *tmp;
1047
1048 if (!handle->cur)
1049 return -EINVAL;
1050 offset = handle->cur->entries[handle->k];
1051 if (!offset)
1052 return -EFAULT;
1053 if (hb)
1054 error = hib_submit_io_async(opf: REQ_OP_READ, page_off: offset, addr: buf, hb);
1055 else
1056 error = hib_submit_io_sync(opf: REQ_OP_READ, page_off: offset, addr: buf);
1057 if (error)
1058 return error;
1059 if (++handle->k >= MAP_PAGE_ENTRIES) {
1060 handle->k = 0;
1061 free_page((unsigned long)handle->maps->map);
1062 tmp = handle->maps;
1063 handle->maps = handle->maps->next;
1064 kfree(objp: tmp);
1065 if (!handle->maps)
1066 release_swap_reader(handle);
1067 else
1068 handle->cur = handle->maps->map;
1069 }
1070 return error;
1071}
1072
1073static int swap_reader_finish(struct swap_map_handle *handle)
1074{
1075 release_swap_reader(handle);
1076
1077 return 0;
1078}
1079
1080/**
1081 * load_image - load the image using the swap map handle
1082 * @handle and the snapshot handle @snapshot
1083 * (assume there are @nr_pages pages to load)
1084 */
1085
1086static int load_image(struct swap_map_handle *handle,
1087 struct snapshot_handle *snapshot,
1088 unsigned int nr_to_read)
1089{
1090 unsigned int m;
1091 int ret = 0;
1092 ktime_t start;
1093 ktime_t stop;
1094 struct hib_bio_batch hb;
1095 int err2;
1096 unsigned nr_pages;
1097
1098 hib_init_batch(hb: &hb);
1099
1100 clean_pages_on_read = true;
1101 pr_info("Loading image data pages (%u pages)...\n", nr_to_read);
1102 m = nr_to_read / 10;
1103 if (!m)
1104 m = 1;
1105 nr_pages = 0;
1106 start = ktime_get();
1107 for ( ; ; ) {
1108 ret = snapshot_write_next(handle: snapshot);
1109 if (ret <= 0)
1110 break;
1111 ret = swap_read_page(handle, data_of(*snapshot), hb: &hb);
1112 if (ret)
1113 break;
1114 if (snapshot->sync_read)
1115 ret = hib_wait_io(hb: &hb);
1116 if (ret)
1117 break;
1118 if (!(nr_pages % m))
1119 pr_info("Image loading progress: %3d%%\n",
1120 nr_pages / m * 10);
1121 nr_pages++;
1122 }
1123 err2 = hib_wait_io(hb: &hb);
1124 hib_finish_batch(hb: &hb);
1125 stop = ktime_get();
1126 if (!ret)
1127 ret = err2;
1128 if (!ret) {
1129 pr_info("Image loading done\n");
1130 ret = snapshot_write_finalize(handle: snapshot);
1131 if (!ret && !snapshot_image_loaded(handle: snapshot))
1132 ret = -ENODATA;
1133 }
1134 swsusp_show_speed(start, stop, nr_to_read, "Read");
1135 return ret;
1136}
1137
1138/*
1139 * Structure used for data decompression.
1140 */
1141struct dec_data {
1142 struct task_struct *thr; /* thread */
1143 struct crypto_acomp *cc; /* crypto compressor */
1144 struct acomp_req *cr; /* crypto request */
1145 atomic_t ready; /* ready to start flag */
1146 atomic_t stop; /* ready to stop flag */
1147 int ret; /* return code */
1148 wait_queue_head_t go; /* start decompression */
1149 wait_queue_head_t done; /* decompression done */
1150 size_t unc_len; /* uncompressed length */
1151 size_t cmp_len; /* compressed length */
1152 unsigned char unc[UNC_SIZE]; /* uncompressed buffer */
1153 unsigned char cmp[CMP_SIZE]; /* compressed buffer */
1154};
1155
1156/*
1157 * Decompression function that runs in its own thread.
1158 */
1159static int decompress_threadfn(void *data)
1160{
1161 struct dec_data *d = data;
1162
1163 while (1) {
1164 wait_event(d->go, atomic_read_acquire(&d->ready) ||
1165 kthread_should_stop());
1166 if (kthread_should_stop()) {
1167 d->thr = NULL;
1168 d->ret = -1;
1169 atomic_set_release(v: &d->stop, i: 1);
1170 wake_up(&d->done);
1171 break;
1172 }
1173 atomic_set(v: &d->ready, i: 0);
1174
1175 acomp_request_set_callback(req: d->cr, CRYPTO_TFM_REQ_MAY_SLEEP,
1176 NULL, NULL);
1177 acomp_request_set_src_nondma(req: d->cr, src: d->cmp + CMP_HEADER,
1178 slen: d->cmp_len);
1179 acomp_request_set_dst_nondma(req: d->cr, dst: d->unc, UNC_SIZE);
1180 d->ret = crypto_acomp_decompress(req: d->cr);
1181 d->unc_len = d->cr->dlen;
1182
1183 if (clean_pages_on_decompress)
1184 flush_icache_range(start: (unsigned long)d->unc,
1185 end: (unsigned long)d->unc + d->unc_len);
1186
1187 atomic_set_release(v: &d->stop, i: 1);
1188 wake_up(&d->done);
1189 }
1190 return 0;
1191}
1192
1193/**
1194 * load_compressed_image - Load compressed image data and decompress it.
1195 * @handle: Swap map handle to use for loading data.
1196 * @snapshot: Image to copy uncompressed data into.
1197 * @nr_to_read: Number of pages to load.
1198 */
1199static int load_compressed_image(struct swap_map_handle *handle,
1200 struct snapshot_handle *snapshot,
1201 unsigned int nr_to_read)
1202{
1203 unsigned int m;
1204 int ret = 0;
1205 int eof = 0;
1206 struct hib_bio_batch hb;
1207 ktime_t start;
1208 ktime_t stop;
1209 unsigned nr_pages;
1210 size_t off;
1211 unsigned i, thr, run_threads, nr_threads;
1212 unsigned ring = 0, pg = 0, ring_size = 0,
1213 have = 0, want, need, asked = 0;
1214 unsigned long read_pages = 0;
1215 unsigned char **page = NULL;
1216 struct dec_data *data = NULL;
1217 struct crc_data *crc = NULL;
1218
1219 hib_init_batch(hb: &hb);
1220
1221 /*
1222 * We'll limit the number of threads for decompression to limit memory
1223 * footprint.
1224 */
1225 nr_threads = num_online_cpus() - 1;
1226 nr_threads = clamp_val(nr_threads, 1, CMP_THREADS);
1227
1228 page = vmalloc_array(CMP_MAX_RD_PAGES, sizeof(*page));
1229 if (!page) {
1230 pr_err("Failed to allocate %s page\n", hib_comp_algo);
1231 ret = -ENOMEM;
1232 goto out_clean;
1233 }
1234
1235 data = vcalloc(nr_threads, sizeof(*data));
1236 if (!data) {
1237 pr_err("Failed to allocate %s data\n", hib_comp_algo);
1238 ret = -ENOMEM;
1239 goto out_clean;
1240 }
1241
1242 crc = kzalloc(sizeof(*crc), GFP_KERNEL);
1243 if (!crc) {
1244 pr_err("Failed to allocate crc\n");
1245 ret = -ENOMEM;
1246 goto out_clean;
1247 }
1248
1249 clean_pages_on_decompress = true;
1250
1251 /*
1252 * Start the decompression threads.
1253 */
1254 for (thr = 0; thr < nr_threads; thr++) {
1255 init_waitqueue_head(&data[thr].go);
1256 init_waitqueue_head(&data[thr].done);
1257
1258 data[thr].cc = crypto_alloc_acomp(alg_name: hib_comp_algo, type: 0, CRYPTO_ALG_ASYNC);
1259 if (IS_ERR_OR_NULL(ptr: data[thr].cc)) {
1260 pr_err("Could not allocate comp stream %ld\n", PTR_ERR(data[thr].cc));
1261 ret = -EFAULT;
1262 goto out_clean;
1263 }
1264
1265 data[thr].cr = acomp_request_alloc(data[thr].cc);
1266 if (!data[thr].cr) {
1267 pr_err("Could not allocate comp request\n");
1268 ret = -ENOMEM;
1269 goto out_clean;
1270 }
1271
1272 data[thr].thr = kthread_run(decompress_threadfn,
1273 &data[thr],
1274 "image_decompress/%u", thr);
1275 if (IS_ERR(ptr: data[thr].thr)) {
1276 data[thr].thr = NULL;
1277 pr_err("Cannot start decompression threads\n");
1278 ret = -ENOMEM;
1279 goto out_clean;
1280 }
1281 }
1282
1283 /*
1284 * Start the CRC32 thread.
1285 */
1286 init_waitqueue_head(&crc->go);
1287 init_waitqueue_head(&crc->done);
1288
1289 handle->crc32 = 0;
1290 crc->crc32 = &handle->crc32;
1291 for (thr = 0; thr < nr_threads; thr++) {
1292 crc->unc[thr] = data[thr].unc;
1293 crc->unc_len[thr] = &data[thr].unc_len;
1294 }
1295
1296 crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
1297 if (IS_ERR(ptr: crc->thr)) {
1298 crc->thr = NULL;
1299 pr_err("Cannot start CRC32 thread\n");
1300 ret = -ENOMEM;
1301 goto out_clean;
1302 }
1303
1304 /*
1305 * Set the number of pages for read buffering.
1306 * This is complete guesswork, because we'll only know the real
1307 * picture once prepare_image() is called, which is much later on
1308 * during the image load phase. We'll assume the worst case and
1309 * say that none of the image pages are from high memory.
1310 */
1311 if (low_free_pages() > snapshot_get_image_size())
1312 read_pages = (low_free_pages() - snapshot_get_image_size()) / 2;
1313 read_pages = clamp_val(read_pages, CMP_MIN_RD_PAGES, CMP_MAX_RD_PAGES);
1314
1315 for (i = 0; i < read_pages; i++) {
1316 page[i] = (void *)__get_free_page(i < CMP_PAGES ?
1317 GFP_NOIO | __GFP_HIGH :
1318 GFP_NOIO | __GFP_NOWARN |
1319 __GFP_NORETRY);
1320
1321 if (!page[i]) {
1322 if (i < CMP_PAGES) {
1323 ring_size = i;
1324 pr_err("Failed to allocate %s pages\n", hib_comp_algo);
1325 ret = -ENOMEM;
1326 goto out_clean;
1327 } else {
1328 break;
1329 }
1330 }
1331 }
1332 want = ring_size = i;
1333
1334 pr_info("Using %u thread(s) for %s decompression\n", nr_threads, hib_comp_algo);
1335 pr_info("Loading and decompressing image data (%u pages)...\n",
1336 nr_to_read);
1337 m = nr_to_read / 10;
1338 if (!m)
1339 m = 1;
1340 nr_pages = 0;
1341 start = ktime_get();
1342
1343 ret = snapshot_write_next(handle: snapshot);
1344 if (ret <= 0)
1345 goto out_finish;
1346
1347 for(;;) {
1348 for (i = 0; !eof && i < want; i++) {
1349 ret = swap_read_page(handle, buf: page[ring], hb: &hb);
1350 if (ret) {
1351 /*
1352 * On real read error, finish. On end of data,
1353 * set EOF flag and just exit the read loop.
1354 */
1355 if (handle->cur &&
1356 handle->cur->entries[handle->k]) {
1357 goto out_finish;
1358 } else {
1359 eof = 1;
1360 break;
1361 }
1362 }
1363 if (++ring >= ring_size)
1364 ring = 0;
1365 }
1366 asked += i;
1367 want -= i;
1368
1369 /*
1370 * We are out of data, wait for some more.
1371 */
1372 if (!have) {
1373 if (!asked)
1374 break;
1375
1376 ret = hib_wait_io(hb: &hb);
1377 if (ret)
1378 goto out_finish;
1379 have += asked;
1380 asked = 0;
1381 if (eof)
1382 eof = 2;
1383 }
1384
1385 if (crc->run_threads) {
1386 wait_event(crc->done, atomic_read_acquire(&crc->stop));
1387 atomic_set(v: &crc->stop, i: 0);
1388 crc->run_threads = 0;
1389 }
1390
1391 for (thr = 0; have && thr < nr_threads; thr++) {
1392 data[thr].cmp_len = *(size_t *)page[pg];
1393 if (unlikely(!data[thr].cmp_len ||
1394 data[thr].cmp_len >
1395 bytes_worst_compress(UNC_SIZE))) {
1396 pr_err("Invalid %s compressed length\n", hib_comp_algo);
1397 ret = -1;
1398 goto out_finish;
1399 }
1400
1401 need = DIV_ROUND_UP(data[thr].cmp_len + CMP_HEADER,
1402 PAGE_SIZE);
1403 if (need > have) {
1404 if (eof > 1) {
1405 ret = -1;
1406 goto out_finish;
1407 }
1408 break;
1409 }
1410
1411 for (off = 0;
1412 off < CMP_HEADER + data[thr].cmp_len;
1413 off += PAGE_SIZE) {
1414 memcpy(to: data[thr].cmp + off,
1415 from: page[pg], PAGE_SIZE);
1416 have--;
1417 want++;
1418 if (++pg >= ring_size)
1419 pg = 0;
1420 }
1421
1422 atomic_set_release(v: &data[thr].ready, i: 1);
1423 wake_up(&data[thr].go);
1424 }
1425
1426 /*
1427 * Wait for more data while we are decompressing.
1428 */
1429 if (have < CMP_PAGES && asked) {
1430 ret = hib_wait_io(hb: &hb);
1431 if (ret)
1432 goto out_finish;
1433 have += asked;
1434 asked = 0;
1435 if (eof)
1436 eof = 2;
1437 }
1438
1439 for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
1440 wait_event(data[thr].done,
1441 atomic_read_acquire(&data[thr].stop));
1442 atomic_set(v: &data[thr].stop, i: 0);
1443
1444 ret = data[thr].ret;
1445
1446 if (ret < 0) {
1447 pr_err("%s decompression failed\n", hib_comp_algo);
1448 goto out_finish;
1449 }
1450
1451 if (unlikely(!data[thr].unc_len ||
1452 data[thr].unc_len > UNC_SIZE ||
1453 data[thr].unc_len & (PAGE_SIZE - 1))) {
1454 pr_err("Invalid %s uncompressed length\n", hib_comp_algo);
1455 ret = -1;
1456 goto out_finish;
1457 }
1458
1459 for (off = 0;
1460 off < data[thr].unc_len; off += PAGE_SIZE) {
1461 memcpy(data_of(*snapshot),
1462 from: data[thr].unc + off, PAGE_SIZE);
1463
1464 if (!(nr_pages % m))
1465 pr_info("Image loading progress: %3d%%\n",
1466 nr_pages / m * 10);
1467 nr_pages++;
1468
1469 ret = snapshot_write_next(handle: snapshot);
1470 if (ret <= 0) {
1471 crc->run_threads = thr + 1;
1472 atomic_set_release(v: &crc->ready, i: 1);
1473 wake_up(&crc->go);
1474 goto out_finish;
1475 }
1476 }
1477 }
1478
1479 crc->run_threads = thr;
1480 atomic_set_release(v: &crc->ready, i: 1);
1481 wake_up(&crc->go);
1482 }
1483
1484out_finish:
1485 if (crc->run_threads) {
1486 wait_event(crc->done, atomic_read_acquire(&crc->stop));
1487 atomic_set(v: &crc->stop, i: 0);
1488 }
1489 stop = ktime_get();
1490 if (!ret) {
1491 pr_info("Image loading done\n");
1492 ret = snapshot_write_finalize(handle: snapshot);
1493 if (!ret && !snapshot_image_loaded(handle: snapshot))
1494 ret = -ENODATA;
1495 if (!ret) {
1496 if (swsusp_header->flags & SF_CRC32_MODE) {
1497 if(handle->crc32 != swsusp_header->crc32) {
1498 pr_err("Invalid image CRC32!\n");
1499 ret = -ENODATA;
1500 }
1501 }
1502 }
1503 }
1504 swsusp_show_speed(start, stop, nr_to_read, "Read");
1505out_clean:
1506 hib_finish_batch(hb: &hb);
1507 for (i = 0; i < ring_size; i++)
1508 free_page((unsigned long)page[i]);
1509 if (crc) {
1510 if (crc->thr)
1511 kthread_stop(k: crc->thr);
1512 kfree(objp: crc);
1513 }
1514 if (data) {
1515 for (thr = 0; thr < nr_threads; thr++) {
1516 if (data[thr].thr)
1517 kthread_stop(k: data[thr].thr);
1518 acomp_request_free(req: data[thr].cr);
1519 crypto_free_acomp(tfm: data[thr].cc);
1520 }
1521 vfree(addr: data);
1522 }
1523 vfree(addr: page);
1524
1525 return ret;
1526}
1527
1528/**
1529 * swsusp_read - read the hibernation image.
1530 * @flags_p: flags passed by the "frozen" kernel in the image header should
1531 * be written into this memory location
1532 */
1533
1534int swsusp_read(unsigned int *flags_p)
1535{
1536 int error;
1537 struct swap_map_handle handle;
1538 struct snapshot_handle snapshot;
1539 struct swsusp_info *header;
1540
1541 memset(s: &snapshot, c: 0, n: sizeof(struct snapshot_handle));
1542 error = snapshot_write_next(handle: &snapshot);
1543 if (error < (int)PAGE_SIZE)
1544 return error < 0 ? error : -EFAULT;
1545 header = (struct swsusp_info *)data_of(snapshot);
1546 error = get_swap_reader(handle: &handle, flags_p);
1547 if (error)
1548 goto end;
1549 if (!error)
1550 error = swap_read_page(handle: &handle, buf: header, NULL);
1551 if (!error) {
1552 error = (*flags_p & SF_NOCOMPRESS_MODE) ?
1553 load_image(handle: &handle, snapshot: &snapshot, nr_to_read: header->pages - 1) :
1554 load_compressed_image(handle: &handle, snapshot: &snapshot, nr_to_read: header->pages - 1);
1555 }
1556 swap_reader_finish(handle: &handle);
1557end:
1558 if (!error)
1559 pr_debug("Image successfully loaded\n");
1560 else
1561 pr_debug("Error %d resuming\n", error);
1562 return error;
1563}
1564
1565static void *swsusp_holder;
1566
1567/**
1568 * swsusp_check - Open the resume device and check for the swsusp signature.
1569 * @exclusive: Open the resume device exclusively.
1570 */
1571
1572int swsusp_check(bool exclusive)
1573{
1574 void *holder = exclusive ? &swsusp_holder : NULL;
1575 int error;
1576
1577 hib_resume_bdev_file = bdev_file_open_by_dev(dev: swsusp_resume_device,
1578 BLK_OPEN_READ, holder, NULL);
1579 if (!IS_ERR(ptr: hib_resume_bdev_file)) {
1580 clear_page(page: swsusp_header);
1581 error = hib_submit_io_sync(opf: REQ_OP_READ, page_off: swsusp_resume_block,
1582 addr: swsusp_header);
1583 if (error)
1584 goto put;
1585
1586 if (!memcmp(HIBERNATE_SIG, swsusp_header->sig, 10)) {
1587 memcpy(to: swsusp_header->sig, from: swsusp_header->orig_sig, len: 10);
1588 swsusp_header_flags = swsusp_header->flags;
1589 /* Reset swap signature now */
1590 error = hib_submit_io_sync(opf: REQ_OP_WRITE | REQ_SYNC,
1591 page_off: swsusp_resume_block,
1592 addr: swsusp_header);
1593 } else {
1594 error = -EINVAL;
1595 }
1596 if (!error && swsusp_header->flags & SF_HW_SIG &&
1597 swsusp_header->hw_sig != swsusp_hardware_signature) {
1598 pr_info("Suspend image hardware signature mismatch (%08x now %08x); aborting resume.\n",
1599 swsusp_header->hw_sig, swsusp_hardware_signature);
1600 error = -EINVAL;
1601 }
1602
1603put:
1604 if (error)
1605 bdev_fput(bdev_file: hib_resume_bdev_file);
1606 else
1607 pr_debug("Image signature found, resuming\n");
1608 } else {
1609 error = PTR_ERR(ptr: hib_resume_bdev_file);
1610 }
1611
1612 if (error)
1613 pr_debug("Image not found (code %d)\n", error);
1614
1615 return error;
1616}
1617
1618/**
1619 * swsusp_close - close resume device.
1620 */
1621
1622void swsusp_close(void)
1623{
1624 if (IS_ERR(ptr: hib_resume_bdev_file)) {
1625 pr_debug("Image device not initialised\n");
1626 return;
1627 }
1628
1629 fput(hib_resume_bdev_file);
1630}
1631
1632/**
1633 * swsusp_unmark - Unmark swsusp signature in the resume device
1634 */
1635
1636#ifdef CONFIG_SUSPEND
1637int swsusp_unmark(void)
1638{
1639 int error;
1640
1641 hib_submit_io_sync(opf: REQ_OP_READ, page_off: swsusp_resume_block, addr: swsusp_header);
1642 if (!memcmp(HIBERNATE_SIG,swsusp_header->sig, 10)) {
1643 memcpy(to: swsusp_header->sig,from: swsusp_header->orig_sig, len: 10);
1644 error = hib_submit_io_sync(opf: REQ_OP_WRITE | REQ_SYNC,
1645 page_off: swsusp_resume_block,
1646 addr: swsusp_header);
1647 } else {
1648 pr_err("Cannot find swsusp signature!\n");
1649 error = -ENODEV;
1650 }
1651
1652 /*
1653 * We just returned from suspend, we don't need the image any more.
1654 */
1655 free_all_swap_pages(swap: root_swap);
1656
1657 return error;
1658}
1659#endif
1660
1661static int __init swsusp_header_init(void)
1662{
1663 swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);
1664 if (!swsusp_header)
1665 panic(fmt: "Could not allocate memory for swsusp_header\n");
1666 return 0;
1667}
1668
1669core_initcall(swsusp_header_init);
1670