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/device.h>
20 #include <linux/bio.h>
21 #include <linux/blkdev.h>
22 #include <linux/swap.h>
23 #include <linux/swapops.h>
24 #include <linux/pm.h>
25 #include <linux/slab.h>
26 #include <linux/vmalloc.h>
27 #include <linux/cpumask.h>
28 #include <linux/atomic.h>
29 #include <linux/kthread.h>
30 #include <linux/crc32.h>
31 #include <linux/ktime.h>
32 #include <trace/hooks/bl_hib.h>
33
34 #include "power.h"
35
36 #define HIBERNATE_SIG "S1SUSPEND"
37
38 u32 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 */
45 static bool clean_pages_on_read;
46 static 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 */
low_free_pages(void)67 static 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 */
reqd_free_pages(void)76 static inline unsigned long reqd_free_pages(void)
77 {
78 return low_free_pages() / 2;
79 }
80
81 struct swap_map_page {
82 sector_t entries[MAP_PAGE_ENTRIES];
83 sector_t next_swap;
84 };
85
86 struct 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
96 struct 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
106 struct 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
117 static 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
124 struct swsusp_extent {
125 struct rb_node node;
126 unsigned long start;
127 unsigned long end;
128 };
129
130 static struct rb_root swsusp_extents = RB_ROOT;
131
swsusp_extents_insert(unsigned long swap_offset)132 static 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(&ext->node, parent, 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
alloc_swapdev_block(int swap)178 sector_t alloc_swapdev_block(int swap)
179 {
180 unsigned long offset;
181
182 offset = swp_offset(get_swap_page_of_type(swap));
183 if (offset) {
184 if (swsusp_extents_insert(offset))
185 swap_free(swp_entry(swap, offset));
186 else
187 return swapdev_block(swap, offset);
188 }
189 return 0;
190 }
191 EXPORT_SYMBOL_GPL(alloc_swapdev_block);
192
193 /*
194 * free_all_swap_pages - free swap pages allocated for saving image data.
195 * It also frees the extents used to register which swap entries had been
196 * allocated.
197 */
198
free_all_swap_pages(int swap)199 void free_all_swap_pages(int swap)
200 {
201 struct rb_node *node;
202
203 while ((node = swsusp_extents.rb_node)) {
204 struct swsusp_extent *ext;
205
206 ext = rb_entry(node, struct swsusp_extent, node);
207 rb_erase(node, &swsusp_extents);
208 swap_free_nr(swp_entry(swap, ext->start),
209 ext->end - ext->start + 1);
210
211 kfree(ext);
212 }
213 }
214
swsusp_swap_in_use(void)215 int swsusp_swap_in_use(void)
216 {
217 return (swsusp_extents.rb_node != NULL);
218 }
219
220 /*
221 * General things
222 */
223
224 static unsigned short root_swap = 0xffff;
225 static struct file *hib_resume_bdev_file;
226
227 struct hib_bio_batch {
228 atomic_t count;
229 wait_queue_head_t wait;
230 blk_status_t error;
231 struct blk_plug plug;
232 };
233
hib_init_batch(struct hib_bio_batch * hb)234 static void hib_init_batch(struct hib_bio_batch *hb)
235 {
236 atomic_set(&hb->count, 0);
237 init_waitqueue_head(&hb->wait);
238 hb->error = BLK_STS_OK;
239 blk_start_plug(&hb->plug);
240 }
241
hib_finish_batch(struct hib_bio_batch * hb)242 static void hib_finish_batch(struct hib_bio_batch *hb)
243 {
244 blk_finish_plug(&hb->plug);
245 }
246
hib_end_io(struct bio * bio)247 static void hib_end_io(struct bio *bio)
248 {
249 struct hib_bio_batch *hb = bio->bi_private;
250 struct page *page = bio_first_page_all(bio);
251
252 if (bio->bi_status) {
253 pr_alert("Read-error on swap-device (%u:%u:%Lu)\n",
254 MAJOR(bio_dev(bio)), MINOR(bio_dev(bio)),
255 (unsigned long long)bio->bi_iter.bi_sector);
256 }
257
258 if (bio_data_dir(bio) == WRITE)
259 put_page(page);
260 else if (clean_pages_on_read)
261 flush_icache_range((unsigned long)page_address(page),
262 (unsigned long)page_address(page) + PAGE_SIZE);
263
264 if (bio->bi_status && !hb->error)
265 hb->error = bio->bi_status;
266 if (atomic_dec_and_test(&hb->count))
267 wake_up(&hb->wait);
268
269 bio_put(bio);
270 }
271
hib_submit_io(blk_opf_t opf,pgoff_t page_off,void * addr,struct hib_bio_batch * hb)272 static int hib_submit_io(blk_opf_t opf, pgoff_t page_off, void *addr,
273 struct hib_bio_batch *hb)
274 {
275 struct page *page = virt_to_page(addr);
276 struct bio *bio;
277 int error = 0;
278
279 bio = bio_alloc(file_bdev(hib_resume_bdev_file), 1, opf,
280 GFP_NOIO | __GFP_HIGH);
281 bio->bi_iter.bi_sector = page_off * (PAGE_SIZE >> 9);
282
283 if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
284 pr_err("Adding page to bio failed at %llu\n",
285 (unsigned long long)bio->bi_iter.bi_sector);
286 bio_put(bio);
287 return -EFAULT;
288 }
289
290 if (hb) {
291 bio->bi_end_io = hib_end_io;
292 bio->bi_private = hb;
293 atomic_inc(&hb->count);
294 submit_bio(bio);
295 } else {
296 error = submit_bio_wait(bio);
297 bio_put(bio);
298 }
299
300 return error;
301 }
302
hib_wait_io(struct hib_bio_batch * hb)303 static int hib_wait_io(struct hib_bio_batch *hb)
304 {
305 /*
306 * We are relying on the behavior of blk_plug that a thread with
307 * a plug will flush the plug list before sleeping.
308 */
309 wait_event(hb->wait, atomic_read(&hb->count) == 0);
310 return blk_status_to_errno(hb->error);
311 }
312
313 /*
314 * Saving part
315 */
mark_swapfiles(struct swap_map_handle * handle,unsigned int flags)316 static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
317 {
318 int error;
319
320 hib_submit_io(REQ_OP_READ, swsusp_resume_block, swsusp_header, NULL);
321 if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||
322 !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {
323 memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);
324 memcpy(swsusp_header->sig, HIBERNATE_SIG, 10);
325 swsusp_header->image = handle->first_sector;
326 if (swsusp_hardware_signature) {
327 swsusp_header->hw_sig = swsusp_hardware_signature;
328 flags |= SF_HW_SIG;
329 }
330 swsusp_header->flags = flags;
331 if (flags & SF_CRC32_MODE)
332 swsusp_header->crc32 = handle->crc32;
333 error = hib_submit_io(REQ_OP_WRITE | REQ_SYNC,
334 swsusp_resume_block, swsusp_header, NULL);
335 } else {
336 pr_err("Swap header not found!\n");
337 error = -ENODEV;
338 }
339 return error;
340 }
341
342 /*
343 * Hold the swsusp_header flag. This is used in software_resume() in
344 * 'kernel/power/hibernate' to check if the image is compressed and query
345 * for the compression algorithm support(if so).
346 */
347 unsigned int swsusp_header_flags;
348
349 /**
350 * swsusp_swap_check - check if the resume device is a swap device
351 * and get its index (if so)
352 *
353 * This is called before saving image
354 */
swsusp_swap_check(void)355 static int swsusp_swap_check(void)
356 {
357 int res;
358
359 if (swsusp_resume_device)
360 res = swap_type_of(swsusp_resume_device, swsusp_resume_block);
361 else
362 res = find_first_swap(&swsusp_resume_device);
363 if (res < 0)
364 return res;
365 root_swap = res;
366
367 hib_resume_bdev_file = bdev_file_open_by_dev(swsusp_resume_device,
368 BLK_OPEN_WRITE, NULL, NULL);
369 if (IS_ERR(hib_resume_bdev_file))
370 return PTR_ERR(hib_resume_bdev_file);
371
372 return 0;
373 }
374
375 /**
376 * write_page - Write one page to given swap location.
377 * @buf: Address we're writing.
378 * @offset: Offset of the swap page we're writing to.
379 * @hb: bio completion batch
380 */
381
write_page(void * buf,sector_t offset,struct hib_bio_batch * hb)382 static int write_page(void *buf, sector_t offset, struct hib_bio_batch *hb)
383 {
384 void *src;
385 int ret;
386
387 if (!offset)
388 return -ENOSPC;
389
390 if (hb) {
391 src = (void *)__get_free_page(GFP_NOIO | __GFP_NOWARN |
392 __GFP_NORETRY);
393 if (src) {
394 copy_page(src, buf);
395 } else {
396 ret = hib_wait_io(hb); /* Free pages */
397 if (ret)
398 return ret;
399 src = (void *)__get_free_page(GFP_NOIO |
400 __GFP_NOWARN |
401 __GFP_NORETRY);
402 if (src) {
403 copy_page(src, buf);
404 } else {
405 WARN_ON_ONCE(1);
406 hb = NULL; /* Go synchronous */
407 src = buf;
408 }
409 }
410 } else {
411 src = buf;
412 }
413 return hib_submit_io(REQ_OP_WRITE | REQ_SYNC, offset, src, hb);
414 }
415
release_swap_writer(struct swap_map_handle * handle)416 static void release_swap_writer(struct swap_map_handle *handle)
417 {
418 if (handle->cur)
419 free_page((unsigned long)handle->cur);
420 handle->cur = NULL;
421 }
422
get_swap_writer(struct swap_map_handle * handle)423 static int get_swap_writer(struct swap_map_handle *handle)
424 {
425 int ret;
426
427 ret = swsusp_swap_check();
428 if (ret) {
429 if (ret != -ENOSPC)
430 pr_err("Cannot find swap device, try swapon -a\n");
431 return ret;
432 }
433 handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL);
434 if (!handle->cur) {
435 ret = -ENOMEM;
436 goto err_close;
437 }
438 handle->cur_swap = alloc_swapdev_block(root_swap);
439 if (!handle->cur_swap) {
440 ret = -ENOSPC;
441 goto err_rel;
442 }
443 handle->k = 0;
444 handle->reqd_free_pages = reqd_free_pages();
445 handle->first_sector = handle->cur_swap;
446 return 0;
447 err_rel:
448 release_swap_writer(handle);
449 err_close:
450 swsusp_close();
451 return ret;
452 }
453
swap_write_page(struct swap_map_handle * handle,void * buf,struct hib_bio_batch * hb)454 static int swap_write_page(struct swap_map_handle *handle, void *buf,
455 struct hib_bio_batch *hb)
456 {
457 int error;
458 sector_t offset;
459 bool skip = false;
460
461 if (!handle->cur)
462 return -EINVAL;
463 offset = alloc_swapdev_block(root_swap);
464 error = write_page(buf, offset, hb);
465 if (error)
466 return error;
467 handle->cur->entries[handle->k++] = offset;
468 if (handle->k >= MAP_PAGE_ENTRIES) {
469 offset = alloc_swapdev_block(root_swap);
470 if (!offset)
471 return -ENOSPC;
472 handle->cur->next_swap = offset;
473 trace_android_vh_skip_swap_map_write(&skip);
474 if (!skip) {
475 error = write_page(handle->cur, handle->cur_swap, hb);
476 if (error)
477 goto out;
478 }
479 clear_page(handle->cur);
480 handle->cur_swap = offset;
481 handle->k = 0;
482
483 if (hb && low_free_pages() <= handle->reqd_free_pages) {
484 error = hib_wait_io(hb);
485 if (error)
486 goto out;
487 /*
488 * Recalculate the number of required free pages, to
489 * make sure we never take more than half.
490 */
491 handle->reqd_free_pages = reqd_free_pages();
492 }
493 }
494 out:
495 return error;
496 }
497
flush_swap_writer(struct swap_map_handle * handle)498 static int flush_swap_writer(struct swap_map_handle *handle)
499 {
500 if (handle->cur && handle->cur_swap)
501 return write_page(handle->cur, handle->cur_swap, NULL);
502 else
503 return -EINVAL;
504 }
505
swap_writer_finish(struct swap_map_handle * handle,unsigned int flags,int error)506 static int swap_writer_finish(struct swap_map_handle *handle,
507 unsigned int flags, int error)
508 {
509 if (!error) {
510 pr_info("S");
511 error = mark_swapfiles(handle, flags);
512 pr_cont("|\n");
513 flush_swap_writer(handle);
514 }
515
516 if (error)
517 free_all_swap_pages(root_swap);
518 release_swap_writer(handle);
519 swsusp_close();
520
521 return error;
522 }
523
524 /*
525 * Bytes we need for compressed data in worst case. We assume(limitation)
526 * this is the worst of all the compression algorithms.
527 */
528 #define bytes_worst_compress(x) ((x) + ((x) / 16) + 64 + 3 + 2)
529
530 /* We need to remember how much compressed data we need to read. */
531 #define CMP_HEADER sizeof(size_t)
532
533 /* Number of pages/bytes we'll compress at one time. */
534 #define UNC_PAGES 32
535 #define UNC_SIZE (UNC_PAGES * PAGE_SIZE)
536
537 /* Number of pages we need for compressed data (worst case). */
538 #define CMP_PAGES DIV_ROUND_UP(bytes_worst_compress(UNC_SIZE) + \
539 CMP_HEADER, PAGE_SIZE)
540 #define CMP_SIZE (CMP_PAGES * PAGE_SIZE)
541
542 /* Maximum number of threads for compression/decompression. */
543 #define CMP_THREADS 3
544
545 /* Minimum/maximum number of pages for read buffering. */
546 #define CMP_MIN_RD_PAGES 1024
547 #define CMP_MAX_RD_PAGES 8192
548
549 /**
550 * save_image - save the suspend image data
551 */
552
save_image(struct swap_map_handle * handle,struct snapshot_handle * snapshot,unsigned int nr_to_write)553 static int save_image(struct swap_map_handle *handle,
554 struct snapshot_handle *snapshot,
555 unsigned int nr_to_write)
556 {
557 unsigned int m;
558 int ret;
559 int nr_pages;
560 int err2;
561 struct hib_bio_batch hb;
562 ktime_t start;
563 ktime_t stop;
564
565 hib_init_batch(&hb);
566
567 pr_info("Saving image data pages (%u pages)...\n",
568 nr_to_write);
569 m = nr_to_write / 10;
570 if (!m)
571 m = 1;
572 nr_pages = 0;
573 start = ktime_get();
574 while (1) {
575 ret = snapshot_read_next(snapshot);
576 if (ret <= 0)
577 break;
578 trace_android_vh_encrypt_page(data_of(*snapshot));
579 ret = swap_write_page(handle, data_of(*snapshot), &hb);
580 if (ret)
581 break;
582 if (!(nr_pages % m))
583 pr_info("Image saving progress: %3d%%\n",
584 nr_pages / m * 10);
585 nr_pages++;
586 }
587 err2 = hib_wait_io(&hb);
588 hib_finish_batch(&hb);
589 stop = ktime_get();
590 if (!ret)
591 ret = err2;
592 if (!ret)
593 pr_info("Image saving done\n");
594 swsusp_show_speed(start, stop, nr_to_write, "Wrote");
595 return ret;
596 }
597
598 /*
599 * Structure used for CRC32.
600 */
601 struct crc_data {
602 struct task_struct *thr; /* thread */
603 atomic_t ready; /* ready to start flag */
604 atomic_t stop; /* ready to stop flag */
605 unsigned run_threads; /* nr current threads */
606 wait_queue_head_t go; /* start crc update */
607 wait_queue_head_t done; /* crc update done */
608 u32 *crc32; /* points to handle's crc32 */
609 size_t *unc_len[CMP_THREADS]; /* uncompressed lengths */
610 unsigned char *unc[CMP_THREADS]; /* uncompressed data */
611 };
612
613 /*
614 * CRC32 update function that runs in its own thread.
615 */
crc32_threadfn(void * data)616 static int crc32_threadfn(void *data)
617 {
618 struct crc_data *d = data;
619 unsigned i;
620
621 while (1) {
622 wait_event(d->go, atomic_read_acquire(&d->ready) ||
623 kthread_should_stop());
624 if (kthread_should_stop()) {
625 d->thr = NULL;
626 atomic_set_release(&d->stop, 1);
627 wake_up(&d->done);
628 break;
629 }
630 atomic_set(&d->ready, 0);
631
632 for (i = 0; i < d->run_threads; i++)
633 *d->crc32 = crc32_le(*d->crc32,
634 d->unc[i], *d->unc_len[i]);
635 atomic_set_release(&d->stop, 1);
636 wake_up(&d->done);
637 }
638 return 0;
639 }
640 /*
641 * Structure used for data compression.
642 */
643 struct cmp_data {
644 struct task_struct *thr; /* thread */
645 struct crypto_comp *cc; /* crypto compressor stream */
646 atomic_t ready; /* ready to start flag */
647 atomic_t stop; /* ready to stop flag */
648 int ret; /* return code */
649 wait_queue_head_t go; /* start compression */
650 wait_queue_head_t done; /* compression done */
651 size_t unc_len; /* uncompressed length */
652 size_t cmp_len; /* compressed length */
653 unsigned char unc[UNC_SIZE]; /* uncompressed buffer */
654 unsigned char cmp[CMP_SIZE]; /* compressed buffer */
655 };
656
657 /* Indicates the image size after compression */
658 static atomic_t compressed_size = ATOMIC_INIT(0);
659
660 /*
661 * Compression function that runs in its own thread.
662 */
compress_threadfn(void * data)663 static int compress_threadfn(void *data)
664 {
665 struct cmp_data *d = data;
666 unsigned int cmp_len = 0;
667
668 while (1) {
669 wait_event(d->go, atomic_read_acquire(&d->ready) ||
670 kthread_should_stop());
671 if (kthread_should_stop()) {
672 d->thr = NULL;
673 d->ret = -1;
674 atomic_set_release(&d->stop, 1);
675 wake_up(&d->done);
676 break;
677 }
678 atomic_set(&d->ready, 0);
679
680 cmp_len = CMP_SIZE - CMP_HEADER;
681 d->ret = crypto_comp_compress(d->cc, d->unc, d->unc_len,
682 d->cmp + CMP_HEADER,
683 &cmp_len);
684 d->cmp_len = cmp_len;
685
686 atomic_set(&compressed_size, atomic_read(&compressed_size) + d->cmp_len);
687 atomic_set_release(&d->stop, 1);
688 wake_up(&d->done);
689 }
690 return 0;
691 }
692
693 /**
694 * save_compressed_image - Save the suspend image data after compression.
695 * @handle: Swap map handle to use for saving the image.
696 * @snapshot: Image to read data from.
697 * @nr_to_write: Number of pages to save.
698 */
save_compressed_image(struct swap_map_handle * handle,struct snapshot_handle * snapshot,unsigned int nr_to_write)699 static int save_compressed_image(struct swap_map_handle *handle,
700 struct snapshot_handle *snapshot,
701 unsigned int nr_to_write)
702 {
703 unsigned int m;
704 int ret = 0;
705 int nr_pages;
706 int err2;
707 struct hib_bio_batch hb;
708 ktime_t start;
709 ktime_t stop;
710 size_t off;
711 unsigned thr, run_threads, nr_threads;
712 unsigned char *page = NULL;
713 struct cmp_data *data = NULL;
714 struct crc_data *crc = NULL;
715
716 hib_init_batch(&hb);
717
718 atomic_set(&compressed_size, 0);
719
720 /*
721 * We'll limit the number of threads for compression to limit memory
722 * footprint.
723 */
724 nr_threads = num_online_cpus() - 1;
725 nr_threads = clamp_val(nr_threads, 1, CMP_THREADS);
726
727 page = (void *)__get_free_page(GFP_NOIO | __GFP_HIGH);
728 if (!page) {
729 pr_err("Failed to allocate %s page\n", hib_comp_algo);
730 ret = -ENOMEM;
731 goto out_clean;
732 }
733
734 data = vzalloc(array_size(nr_threads, sizeof(*data)));
735 if (!data) {
736 pr_err("Failed to allocate %s data\n", hib_comp_algo);
737 ret = -ENOMEM;
738 goto out_clean;
739 }
740
741 crc = kzalloc(sizeof(*crc), GFP_KERNEL);
742 if (!crc) {
743 pr_err("Failed to allocate crc\n");
744 ret = -ENOMEM;
745 goto out_clean;
746 }
747
748 /*
749 * Start the compression threads.
750 */
751 for (thr = 0; thr < nr_threads; thr++) {
752 init_waitqueue_head(&data[thr].go);
753 init_waitqueue_head(&data[thr].done);
754
755 data[thr].cc = crypto_alloc_comp(hib_comp_algo, 0, 0);
756 if (IS_ERR_OR_NULL(data[thr].cc)) {
757 pr_err("Could not allocate comp stream %ld\n", PTR_ERR(data[thr].cc));
758 ret = -EFAULT;
759 goto out_clean;
760 }
761
762 data[thr].thr = kthread_run(compress_threadfn,
763 &data[thr],
764 "image_compress/%u", thr);
765 if (IS_ERR(data[thr].thr)) {
766 data[thr].thr = NULL;
767 pr_err("Cannot start compression threads\n");
768 ret = -ENOMEM;
769 goto out_clean;
770 }
771 }
772
773 /*
774 * Start the CRC32 thread.
775 */
776 init_waitqueue_head(&crc->go);
777 init_waitqueue_head(&crc->done);
778
779 handle->crc32 = 0;
780 crc->crc32 = &handle->crc32;
781 for (thr = 0; thr < nr_threads; thr++) {
782 crc->unc[thr] = data[thr].unc;
783 crc->unc_len[thr] = &data[thr].unc_len;
784 }
785
786 crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
787 if (IS_ERR(crc->thr)) {
788 crc->thr = NULL;
789 pr_err("Cannot start CRC32 thread\n");
790 ret = -ENOMEM;
791 goto out_clean;
792 }
793
794 /*
795 * Adjust the number of required free pages after all allocations have
796 * been done. We don't want to run out of pages when writing.
797 */
798 handle->reqd_free_pages = reqd_free_pages();
799
800 pr_info("Using %u thread(s) for %s compression\n", nr_threads, hib_comp_algo);
801 pr_info("Compressing and saving image data (%u pages)...\n",
802 nr_to_write);
803 m = nr_to_write / 10;
804 if (!m)
805 m = 1;
806 nr_pages = 0;
807 start = ktime_get();
808 for (;;) {
809 for (thr = 0; thr < nr_threads; thr++) {
810 for (off = 0; off < UNC_SIZE; off += PAGE_SIZE) {
811 ret = snapshot_read_next(snapshot);
812 if (ret < 0)
813 goto out_finish;
814
815 if (!ret)
816 break;
817
818 memcpy(data[thr].unc + off,
819 data_of(*snapshot), PAGE_SIZE);
820
821 if (!(nr_pages % m))
822 pr_info("Image saving progress: %3d%%\n",
823 nr_pages / m * 10);
824 nr_pages++;
825 }
826 if (!off)
827 break;
828
829 data[thr].unc_len = off;
830
831 atomic_set_release(&data[thr].ready, 1);
832 wake_up(&data[thr].go);
833 }
834
835 if (!thr)
836 break;
837
838 crc->run_threads = thr;
839 atomic_set_release(&crc->ready, 1);
840 wake_up(&crc->go);
841
842 for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
843 wait_event(data[thr].done,
844 atomic_read_acquire(&data[thr].stop));
845 atomic_set(&data[thr].stop, 0);
846
847 ret = data[thr].ret;
848
849 if (ret < 0) {
850 pr_err("%s compression failed\n", hib_comp_algo);
851 goto out_finish;
852 }
853
854 if (unlikely(!data[thr].cmp_len ||
855 data[thr].cmp_len >
856 bytes_worst_compress(data[thr].unc_len))) {
857 pr_err("Invalid %s compressed length\n", hib_comp_algo);
858 ret = -1;
859 goto out_finish;
860 }
861
862 *(size_t *)data[thr].cmp = data[thr].cmp_len;
863
864 /*
865 * Given we are writing one page at a time to disk, we
866 * copy that much from the buffer, although the last
867 * bit will likely be smaller than full page. This is
868 * OK - we saved the length of the compressed data, so
869 * any garbage at the end will be discarded when we
870 * read it.
871 */
872 for (off = 0;
873 off < CMP_HEADER + data[thr].cmp_len;
874 off += PAGE_SIZE) {
875 memcpy(page, data[thr].cmp + off, PAGE_SIZE);
876
877 trace_android_vh_encrypt_page(page);
878 ret = swap_write_page(handle, page, &hb);
879 if (ret)
880 goto out_finish;
881 }
882 trace_android_vh_hibernate_save_cmp_len(data[thr].cmp_len + CMP_HEADER);
883 }
884
885 wait_event(crc->done, atomic_read_acquire(&crc->stop));
886 atomic_set(&crc->stop, 0);
887 }
888
889 out_finish:
890 err2 = hib_wait_io(&hb);
891 stop = ktime_get();
892 if (!ret)
893 ret = err2;
894 if (!ret)
895 pr_info("Image saving done\n");
896 swsusp_show_speed(start, stop, nr_to_write, "Wrote");
897 pr_info("Image size after compression: %d kbytes\n",
898 (atomic_read(&compressed_size) / 1024));
899
900 out_clean:
901 hib_finish_batch(&hb);
902 if (crc) {
903 if (crc->thr)
904 kthread_stop(crc->thr);
905 kfree(crc);
906 }
907 if (data) {
908 for (thr = 0; thr < nr_threads; thr++) {
909 if (data[thr].thr)
910 kthread_stop(data[thr].thr);
911 if (data[thr].cc)
912 crypto_free_comp(data[thr].cc);
913 }
914 vfree(data);
915 }
916 if (page) free_page((unsigned long)page);
917
918 return ret;
919 }
920
921 /**
922 * enough_swap - Make sure we have enough swap to save the image.
923 *
924 * Returns TRUE or FALSE after checking the total amount of swap
925 * space available from the resume partition.
926 */
927
enough_swap(unsigned int nr_pages)928 static int enough_swap(unsigned int nr_pages)
929 {
930 unsigned int free_swap = count_swap_pages(root_swap, 1);
931 unsigned int required;
932
933 pr_debug("Free swap pages: %u\n", free_swap);
934
935 required = PAGES_FOR_IO + nr_pages;
936 return free_swap > required;
937 }
938
939 /**
940 * swsusp_write - Write entire image and metadata.
941 * @flags: flags to pass to the "boot" kernel in the image header
942 *
943 * It is important _NOT_ to umount filesystems at this point. We want
944 * them synced (in case something goes wrong) but we DO not want to mark
945 * filesystem clean: it is not. (And it does not matter, if we resume
946 * correctly, we'll mark system clean, anyway.)
947 */
948
swsusp_write(unsigned int flags)949 int swsusp_write(unsigned int flags)
950 {
951 struct swap_map_handle handle;
952 struct snapshot_handle snapshot;
953 struct swsusp_info *header;
954 unsigned long pages;
955 int error = 0;
956
957 pages = snapshot_get_image_size();
958
959 /*
960 * The memory allocated by this vendor hook is later freed as part of
961 * PM_POST_HIBERNATION notifier call.
962 */
963 trace_android_vh_hibernated_do_mem_alloc(pages, flags, &error);
964 if (error < 0) {
965 pr_err("Failed to allocate required memory\n");
966 return error;
967 }
968
969 error = get_swap_writer(&handle);
970 if (error) {
971 pr_err("Cannot get swap writer\n");
972 return error;
973 }
974 trace_android_vh_init_aes_encrypt(NULL);
975 if (flags & SF_NOCOMPRESS_MODE) {
976 if (!enough_swap(pages)) {
977 pr_err("Not enough free swap\n");
978 error = -ENOSPC;
979 goto out_finish;
980 }
981 }
982 memset(&snapshot, 0, sizeof(struct snapshot_handle));
983 error = snapshot_read_next(&snapshot);
984 if (error < (int)PAGE_SIZE) {
985 if (error >= 0)
986 error = -EFAULT;
987
988 goto out_finish;
989 }
990 header = (struct swsusp_info *)data_of(snapshot);
991 error = swap_write_page(&handle, header, NULL);
992 if (!error) {
993 error = (flags & SF_NOCOMPRESS_MODE) ?
994 save_image(&handle, &snapshot, pages - 1) :
995 save_compressed_image(&handle, &snapshot, pages - 1);
996 if (!error)
997 trace_android_vh_post_image_save(root_swap);
998 }
999 out_finish:
1000 error = swap_writer_finish(&handle, flags, error);
1001 return error;
1002 }
1003
1004 /*
1005 * The following functions allow us to read data using a swap map
1006 * in a file-like way.
1007 */
1008
release_swap_reader(struct swap_map_handle * handle)1009 static void release_swap_reader(struct swap_map_handle *handle)
1010 {
1011 struct swap_map_page_list *tmp;
1012
1013 while (handle->maps) {
1014 if (handle->maps->map)
1015 free_page((unsigned long)handle->maps->map);
1016 tmp = handle->maps;
1017 handle->maps = handle->maps->next;
1018 kfree(tmp);
1019 }
1020 handle->cur = NULL;
1021 }
1022
get_swap_reader(struct swap_map_handle * handle,unsigned int * flags_p)1023 static int get_swap_reader(struct swap_map_handle *handle,
1024 unsigned int *flags_p)
1025 {
1026 int error;
1027 struct swap_map_page_list *tmp, *last;
1028 sector_t offset;
1029
1030 *flags_p = swsusp_header->flags;
1031
1032 if (!swsusp_header->image) /* how can this happen? */
1033 return -EINVAL;
1034
1035 handle->cur = NULL;
1036 last = handle->maps = NULL;
1037 offset = swsusp_header->image;
1038 while (offset) {
1039 tmp = kzalloc(sizeof(*handle->maps), GFP_KERNEL);
1040 if (!tmp) {
1041 release_swap_reader(handle);
1042 return -ENOMEM;
1043 }
1044 if (!handle->maps)
1045 handle->maps = tmp;
1046 if (last)
1047 last->next = tmp;
1048 last = tmp;
1049
1050 tmp->map = (struct swap_map_page *)
1051 __get_free_page(GFP_NOIO | __GFP_HIGH);
1052 if (!tmp->map) {
1053 release_swap_reader(handle);
1054 return -ENOMEM;
1055 }
1056
1057 error = hib_submit_io(REQ_OP_READ, offset, tmp->map, NULL);
1058 if (error) {
1059 release_swap_reader(handle);
1060 return error;
1061 }
1062 offset = tmp->map->next_swap;
1063 }
1064 handle->k = 0;
1065 handle->cur = handle->maps->map;
1066 return 0;
1067 }
1068
swap_read_page(struct swap_map_handle * handle,void * buf,struct hib_bio_batch * hb)1069 static int swap_read_page(struct swap_map_handle *handle, void *buf,
1070 struct hib_bio_batch *hb)
1071 {
1072 sector_t offset;
1073 int error;
1074 struct swap_map_page_list *tmp;
1075
1076 if (!handle->cur)
1077 return -EINVAL;
1078 offset = handle->cur->entries[handle->k];
1079 if (!offset)
1080 return -EFAULT;
1081 error = hib_submit_io(REQ_OP_READ, offset, buf, hb);
1082 if (error)
1083 return error;
1084 if (++handle->k >= MAP_PAGE_ENTRIES) {
1085 handle->k = 0;
1086 free_page((unsigned long)handle->maps->map);
1087 tmp = handle->maps;
1088 handle->maps = handle->maps->next;
1089 kfree(tmp);
1090 if (!handle->maps)
1091 release_swap_reader(handle);
1092 else
1093 handle->cur = handle->maps->map;
1094 }
1095 return error;
1096 }
1097
swap_reader_finish(struct swap_map_handle * handle)1098 static int swap_reader_finish(struct swap_map_handle *handle)
1099 {
1100 release_swap_reader(handle);
1101
1102 return 0;
1103 }
1104
1105 /**
1106 * load_image - load the image using the swap map handle
1107 * @handle and the snapshot handle @snapshot
1108 * (assume there are @nr_pages pages to load)
1109 */
1110
load_image(struct swap_map_handle * handle,struct snapshot_handle * snapshot,unsigned int nr_to_read)1111 static int load_image(struct swap_map_handle *handle,
1112 struct snapshot_handle *snapshot,
1113 unsigned int nr_to_read)
1114 {
1115 unsigned int m;
1116 int ret = 0;
1117 ktime_t start;
1118 ktime_t stop;
1119 struct hib_bio_batch hb;
1120 int err2;
1121 unsigned nr_pages;
1122
1123 hib_init_batch(&hb);
1124
1125 clean_pages_on_read = true;
1126 pr_info("Loading image data pages (%u pages)...\n", nr_to_read);
1127 m = nr_to_read / 10;
1128 if (!m)
1129 m = 1;
1130 nr_pages = 0;
1131 start = ktime_get();
1132 for ( ; ; ) {
1133 ret = snapshot_write_next(snapshot);
1134 if (ret <= 0)
1135 break;
1136 ret = swap_read_page(handle, data_of(*snapshot), &hb);
1137 if (ret)
1138 break;
1139 if (snapshot->sync_read)
1140 ret = hib_wait_io(&hb);
1141 if (ret)
1142 break;
1143 if (!(nr_pages % m))
1144 pr_info("Image loading progress: %3d%%\n",
1145 nr_pages / m * 10);
1146 nr_pages++;
1147 }
1148 err2 = hib_wait_io(&hb);
1149 hib_finish_batch(&hb);
1150 stop = ktime_get();
1151 if (!ret)
1152 ret = err2;
1153 if (!ret) {
1154 pr_info("Image loading done\n");
1155 ret = snapshot_write_finalize(snapshot);
1156 if (!ret && !snapshot_image_loaded(snapshot))
1157 ret = -ENODATA;
1158 }
1159 swsusp_show_speed(start, stop, nr_to_read, "Read");
1160 return ret;
1161 }
1162
1163 /*
1164 * Structure used for data decompression.
1165 */
1166 struct dec_data {
1167 struct task_struct *thr; /* thread */
1168 struct crypto_comp *cc; /* crypto compressor stream */
1169 atomic_t ready; /* ready to start flag */
1170 atomic_t stop; /* ready to stop flag */
1171 int ret; /* return code */
1172 wait_queue_head_t go; /* start decompression */
1173 wait_queue_head_t done; /* decompression done */
1174 size_t unc_len; /* uncompressed length */
1175 size_t cmp_len; /* compressed length */
1176 unsigned char unc[UNC_SIZE]; /* uncompressed buffer */
1177 unsigned char cmp[CMP_SIZE]; /* compressed buffer */
1178 };
1179
1180 /*
1181 * Decompression function that runs in its own thread.
1182 */
decompress_threadfn(void * data)1183 static int decompress_threadfn(void *data)
1184 {
1185 struct dec_data *d = data;
1186 unsigned int unc_len = 0;
1187
1188 while (1) {
1189 wait_event(d->go, atomic_read_acquire(&d->ready) ||
1190 kthread_should_stop());
1191 if (kthread_should_stop()) {
1192 d->thr = NULL;
1193 d->ret = -1;
1194 atomic_set_release(&d->stop, 1);
1195 wake_up(&d->done);
1196 break;
1197 }
1198 atomic_set(&d->ready, 0);
1199
1200 unc_len = UNC_SIZE;
1201 d->ret = crypto_comp_decompress(d->cc, d->cmp + CMP_HEADER, d->cmp_len,
1202 d->unc, &unc_len);
1203 d->unc_len = unc_len;
1204
1205 if (clean_pages_on_decompress)
1206 flush_icache_range((unsigned long)d->unc,
1207 (unsigned long)d->unc + d->unc_len);
1208
1209 atomic_set_release(&d->stop, 1);
1210 wake_up(&d->done);
1211 }
1212 return 0;
1213 }
1214
1215 /**
1216 * load_compressed_image - Load compressed image data and decompress it.
1217 * @handle: Swap map handle to use for loading data.
1218 * @snapshot: Image to copy uncompressed data into.
1219 * @nr_to_read: Number of pages to load.
1220 */
load_compressed_image(struct swap_map_handle * handle,struct snapshot_handle * snapshot,unsigned int nr_to_read)1221 static int load_compressed_image(struct swap_map_handle *handle,
1222 struct snapshot_handle *snapshot,
1223 unsigned int nr_to_read)
1224 {
1225 unsigned int m;
1226 int ret = 0;
1227 int eof = 0;
1228 struct hib_bio_batch hb;
1229 ktime_t start;
1230 ktime_t stop;
1231 unsigned nr_pages;
1232 size_t off;
1233 unsigned i, thr, run_threads, nr_threads;
1234 unsigned ring = 0, pg = 0, ring_size = 0,
1235 have = 0, want, need, asked = 0;
1236 unsigned long read_pages = 0;
1237 unsigned char **page = NULL;
1238 struct dec_data *data = NULL;
1239 struct crc_data *crc = NULL;
1240
1241 hib_init_batch(&hb);
1242
1243 /*
1244 * We'll limit the number of threads for decompression to limit memory
1245 * footprint.
1246 */
1247 nr_threads = num_online_cpus() - 1;
1248 nr_threads = clamp_val(nr_threads, 1, CMP_THREADS);
1249
1250 page = vmalloc(array_size(CMP_MAX_RD_PAGES, sizeof(*page)));
1251 if (!page) {
1252 pr_err("Failed to allocate %s page\n", hib_comp_algo);
1253 ret = -ENOMEM;
1254 goto out_clean;
1255 }
1256
1257 data = vzalloc(array_size(nr_threads, sizeof(*data)));
1258 if (!data) {
1259 pr_err("Failed to allocate %s data\n", hib_comp_algo);
1260 ret = -ENOMEM;
1261 goto out_clean;
1262 }
1263
1264 crc = kzalloc(sizeof(*crc), GFP_KERNEL);
1265 if (!crc) {
1266 pr_err("Failed to allocate crc\n");
1267 ret = -ENOMEM;
1268 goto out_clean;
1269 }
1270
1271 clean_pages_on_decompress = true;
1272
1273 /*
1274 * Start the decompression threads.
1275 */
1276 for (thr = 0; thr < nr_threads; thr++) {
1277 init_waitqueue_head(&data[thr].go);
1278 init_waitqueue_head(&data[thr].done);
1279
1280 data[thr].cc = crypto_alloc_comp(hib_comp_algo, 0, 0);
1281 if (IS_ERR_OR_NULL(data[thr].cc)) {
1282 pr_err("Could not allocate comp stream %ld\n", PTR_ERR(data[thr].cc));
1283 ret = -EFAULT;
1284 goto out_clean;
1285 }
1286
1287 data[thr].thr = kthread_run(decompress_threadfn,
1288 &data[thr],
1289 "image_decompress/%u", thr);
1290 if (IS_ERR(data[thr].thr)) {
1291 data[thr].thr = NULL;
1292 pr_err("Cannot start decompression threads\n");
1293 ret = -ENOMEM;
1294 goto out_clean;
1295 }
1296 }
1297
1298 /*
1299 * Start the CRC32 thread.
1300 */
1301 init_waitqueue_head(&crc->go);
1302 init_waitqueue_head(&crc->done);
1303
1304 handle->crc32 = 0;
1305 crc->crc32 = &handle->crc32;
1306 for (thr = 0; thr < nr_threads; thr++) {
1307 crc->unc[thr] = data[thr].unc;
1308 crc->unc_len[thr] = &data[thr].unc_len;
1309 }
1310
1311 crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
1312 if (IS_ERR(crc->thr)) {
1313 crc->thr = NULL;
1314 pr_err("Cannot start CRC32 thread\n");
1315 ret = -ENOMEM;
1316 goto out_clean;
1317 }
1318
1319 /*
1320 * Set the number of pages for read buffering.
1321 * This is complete guesswork, because we'll only know the real
1322 * picture once prepare_image() is called, which is much later on
1323 * during the image load phase. We'll assume the worst case and
1324 * say that none of the image pages are from high memory.
1325 */
1326 if (low_free_pages() > snapshot_get_image_size())
1327 read_pages = (low_free_pages() - snapshot_get_image_size()) / 2;
1328 read_pages = clamp_val(read_pages, CMP_MIN_RD_PAGES, CMP_MAX_RD_PAGES);
1329
1330 for (i = 0; i < read_pages; i++) {
1331 page[i] = (void *)__get_free_page(i < CMP_PAGES ?
1332 GFP_NOIO | __GFP_HIGH :
1333 GFP_NOIO | __GFP_NOWARN |
1334 __GFP_NORETRY);
1335
1336 if (!page[i]) {
1337 if (i < CMP_PAGES) {
1338 ring_size = i;
1339 pr_err("Failed to allocate %s pages\n", hib_comp_algo);
1340 ret = -ENOMEM;
1341 goto out_clean;
1342 } else {
1343 break;
1344 }
1345 }
1346 }
1347 want = ring_size = i;
1348
1349 pr_info("Using %u thread(s) for %s decompression\n", nr_threads, hib_comp_algo);
1350 pr_info("Loading and decompressing image data (%u pages)...\n",
1351 nr_to_read);
1352 m = nr_to_read / 10;
1353 if (!m)
1354 m = 1;
1355 nr_pages = 0;
1356 start = ktime_get();
1357
1358 ret = snapshot_write_next(snapshot);
1359 if (ret <= 0)
1360 goto out_finish;
1361
1362 for(;;) {
1363 for (i = 0; !eof && i < want; i++) {
1364 ret = swap_read_page(handle, page[ring], &hb);
1365 if (ret) {
1366 /*
1367 * On real read error, finish. On end of data,
1368 * set EOF flag and just exit the read loop.
1369 */
1370 if (handle->cur &&
1371 handle->cur->entries[handle->k]) {
1372 goto out_finish;
1373 } else {
1374 eof = 1;
1375 break;
1376 }
1377 }
1378 if (++ring >= ring_size)
1379 ring = 0;
1380 }
1381 asked += i;
1382 want -= i;
1383
1384 /*
1385 * We are out of data, wait for some more.
1386 */
1387 if (!have) {
1388 if (!asked)
1389 break;
1390
1391 ret = hib_wait_io(&hb);
1392 if (ret)
1393 goto out_finish;
1394 have += asked;
1395 asked = 0;
1396 if (eof)
1397 eof = 2;
1398 }
1399
1400 if (crc->run_threads) {
1401 wait_event(crc->done, atomic_read_acquire(&crc->stop));
1402 atomic_set(&crc->stop, 0);
1403 crc->run_threads = 0;
1404 }
1405
1406 for (thr = 0; have && thr < nr_threads; thr++) {
1407 data[thr].cmp_len = *(size_t *)page[pg];
1408 if (unlikely(!data[thr].cmp_len ||
1409 data[thr].cmp_len >
1410 bytes_worst_compress(UNC_SIZE))) {
1411 pr_err("Invalid %s compressed length\n", hib_comp_algo);
1412 ret = -1;
1413 goto out_finish;
1414 }
1415
1416 need = DIV_ROUND_UP(data[thr].cmp_len + CMP_HEADER,
1417 PAGE_SIZE);
1418 if (need > have) {
1419 if (eof > 1) {
1420 ret = -1;
1421 goto out_finish;
1422 }
1423 break;
1424 }
1425
1426 for (off = 0;
1427 off < CMP_HEADER + data[thr].cmp_len;
1428 off += PAGE_SIZE) {
1429 memcpy(data[thr].cmp + off,
1430 page[pg], PAGE_SIZE);
1431 have--;
1432 want++;
1433 if (++pg >= ring_size)
1434 pg = 0;
1435 }
1436
1437 atomic_set_release(&data[thr].ready, 1);
1438 wake_up(&data[thr].go);
1439 }
1440
1441 /*
1442 * Wait for more data while we are decompressing.
1443 */
1444 if (have < CMP_PAGES && asked) {
1445 ret = hib_wait_io(&hb);
1446 if (ret)
1447 goto out_finish;
1448 have += asked;
1449 asked = 0;
1450 if (eof)
1451 eof = 2;
1452 }
1453
1454 for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
1455 wait_event(data[thr].done,
1456 atomic_read_acquire(&data[thr].stop));
1457 atomic_set(&data[thr].stop, 0);
1458
1459 ret = data[thr].ret;
1460
1461 if (ret < 0) {
1462 pr_err("%s decompression failed\n", hib_comp_algo);
1463 goto out_finish;
1464 }
1465
1466 if (unlikely(!data[thr].unc_len ||
1467 data[thr].unc_len > UNC_SIZE ||
1468 data[thr].unc_len & (PAGE_SIZE - 1))) {
1469 pr_err("Invalid %s uncompressed length\n", hib_comp_algo);
1470 ret = -1;
1471 goto out_finish;
1472 }
1473
1474 for (off = 0;
1475 off < data[thr].unc_len; off += PAGE_SIZE) {
1476 memcpy(data_of(*snapshot),
1477 data[thr].unc + off, PAGE_SIZE);
1478
1479 if (!(nr_pages % m))
1480 pr_info("Image loading progress: %3d%%\n",
1481 nr_pages / m * 10);
1482 nr_pages++;
1483
1484 ret = snapshot_write_next(snapshot);
1485 if (ret <= 0) {
1486 crc->run_threads = thr + 1;
1487 atomic_set_release(&crc->ready, 1);
1488 wake_up(&crc->go);
1489 goto out_finish;
1490 }
1491 }
1492 }
1493
1494 crc->run_threads = thr;
1495 atomic_set_release(&crc->ready, 1);
1496 wake_up(&crc->go);
1497 }
1498
1499 out_finish:
1500 if (crc->run_threads) {
1501 wait_event(crc->done, atomic_read_acquire(&crc->stop));
1502 atomic_set(&crc->stop, 0);
1503 }
1504 stop = ktime_get();
1505 if (!ret) {
1506 pr_info("Image loading done\n");
1507 ret = snapshot_write_finalize(snapshot);
1508 if (!ret && !snapshot_image_loaded(snapshot))
1509 ret = -ENODATA;
1510 if (!ret) {
1511 if (swsusp_header->flags & SF_CRC32_MODE) {
1512 if(handle->crc32 != swsusp_header->crc32) {
1513 pr_err("Invalid image CRC32!\n");
1514 ret = -ENODATA;
1515 }
1516 }
1517 }
1518 }
1519 swsusp_show_speed(start, stop, nr_to_read, "Read");
1520 out_clean:
1521 hib_finish_batch(&hb);
1522 for (i = 0; i < ring_size; i++)
1523 free_page((unsigned long)page[i]);
1524 if (crc) {
1525 if (crc->thr)
1526 kthread_stop(crc->thr);
1527 kfree(crc);
1528 }
1529 if (data) {
1530 for (thr = 0; thr < nr_threads; thr++) {
1531 if (data[thr].thr)
1532 kthread_stop(data[thr].thr);
1533 if (data[thr].cc)
1534 crypto_free_comp(data[thr].cc);
1535 }
1536 vfree(data);
1537 }
1538 vfree(page);
1539
1540 return ret;
1541 }
1542
1543 /**
1544 * swsusp_read - read the hibernation image.
1545 * @flags_p: flags passed by the "frozen" kernel in the image header should
1546 * be written into this memory location
1547 */
1548
swsusp_read(unsigned int * flags_p)1549 int swsusp_read(unsigned int *flags_p)
1550 {
1551 int error;
1552 struct swap_map_handle handle;
1553 struct snapshot_handle snapshot;
1554 struct swsusp_info *header;
1555
1556 memset(&snapshot, 0, sizeof(struct snapshot_handle));
1557 error = snapshot_write_next(&snapshot);
1558 if (error < (int)PAGE_SIZE)
1559 return error < 0 ? error : -EFAULT;
1560 header = (struct swsusp_info *)data_of(snapshot);
1561 error = get_swap_reader(&handle, flags_p);
1562 if (error)
1563 goto end;
1564 if (!error)
1565 error = swap_read_page(&handle, header, NULL);
1566 if (!error) {
1567 error = (*flags_p & SF_NOCOMPRESS_MODE) ?
1568 load_image(&handle, &snapshot, header->pages - 1) :
1569 load_compressed_image(&handle, &snapshot, header->pages - 1);
1570 }
1571 swap_reader_finish(&handle);
1572 end:
1573 if (!error)
1574 pr_debug("Image successfully loaded\n");
1575 else
1576 pr_debug("Error %d resuming\n", error);
1577 return error;
1578 }
1579
1580 static void *swsusp_holder;
1581
1582 /**
1583 * swsusp_check - Open the resume device and check for the swsusp signature.
1584 * @exclusive: Open the resume device exclusively.
1585 */
1586
swsusp_check(bool exclusive)1587 int swsusp_check(bool exclusive)
1588 {
1589 void *holder = exclusive ? &swsusp_holder : NULL;
1590 int error;
1591
1592 hib_resume_bdev_file = bdev_file_open_by_dev(swsusp_resume_device,
1593 BLK_OPEN_READ, holder, NULL);
1594 if (!IS_ERR(hib_resume_bdev_file)) {
1595 trace_android_vh_save_hib_resume_bdev(hib_resume_bdev_file);
1596 clear_page(swsusp_header);
1597 error = hib_submit_io(REQ_OP_READ, swsusp_resume_block,
1598 swsusp_header, NULL);
1599 if (error)
1600 goto put;
1601
1602 if (!memcmp(HIBERNATE_SIG, swsusp_header->sig, 10)) {
1603 memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10);
1604 swsusp_header_flags = swsusp_header->flags;
1605 /* Reset swap signature now */
1606 error = hib_submit_io(REQ_OP_WRITE | REQ_SYNC,
1607 swsusp_resume_block,
1608 swsusp_header, NULL);
1609 } else {
1610 error = -EINVAL;
1611 }
1612 if (!error && swsusp_header->flags & SF_HW_SIG &&
1613 swsusp_header->hw_sig != swsusp_hardware_signature) {
1614 pr_info("Suspend image hardware signature mismatch (%08x now %08x); aborting resume.\n",
1615 swsusp_header->hw_sig, swsusp_hardware_signature);
1616 error = -EINVAL;
1617 }
1618
1619 put:
1620 if (error)
1621 bdev_fput(hib_resume_bdev_file);
1622 else
1623 pr_debug("Image signature found, resuming\n");
1624 } else {
1625 error = PTR_ERR(hib_resume_bdev_file);
1626 }
1627
1628 if (error)
1629 pr_debug("Image not found (code %d)\n", error);
1630
1631 return error;
1632 }
1633
1634 /**
1635 * swsusp_close - close resume device.
1636 */
1637
swsusp_close(void)1638 void swsusp_close(void)
1639 {
1640 if (IS_ERR(hib_resume_bdev_file)) {
1641 pr_debug("Image device not initialised\n");
1642 return;
1643 }
1644
1645 fput(hib_resume_bdev_file);
1646 }
1647
1648 /**
1649 * swsusp_unmark - Unmark swsusp signature in the resume device
1650 */
1651
1652 #ifdef CONFIG_SUSPEND
swsusp_unmark(void)1653 int swsusp_unmark(void)
1654 {
1655 int error;
1656
1657 hib_submit_io(REQ_OP_READ, swsusp_resume_block,
1658 swsusp_header, NULL);
1659 if (!memcmp(HIBERNATE_SIG,swsusp_header->sig, 10)) {
1660 memcpy(swsusp_header->sig,swsusp_header->orig_sig, 10);
1661 error = hib_submit_io(REQ_OP_WRITE | REQ_SYNC,
1662 swsusp_resume_block,
1663 swsusp_header, NULL);
1664 } else {
1665 pr_err("Cannot find swsusp signature!\n");
1666 error = -ENODEV;
1667 }
1668
1669 /*
1670 * We just returned from suspend, we don't need the image any more.
1671 */
1672 free_all_swap_pages(root_swap);
1673
1674 return error;
1675 }
1676 #endif
1677
swsusp_header_init(void)1678 static int __init swsusp_header_init(void)
1679 {
1680 swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);
1681 if (!swsusp_header)
1682 panic("Could not allocate memory for swsusp_header\n");
1683 return 0;
1684 }
1685
1686 core_initcall(swsusp_header_init);
1687