Commit | Line | Data |
---|---|---|
61159a31 RW |
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@suse.cz> | |
8 | * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl> | |
9 | * | |
10 | * This file is released under the GPLv2. | |
11 | * | |
12 | */ | |
13 | ||
14 | #include <linux/module.h> | |
61159a31 | 15 | #include <linux/file.h> |
61159a31 RW |
16 | #include <linux/delay.h> |
17 | #include <linux/bitops.h> | |
18 | #include <linux/genhd.h> | |
19 | #include <linux/device.h> | |
20 | #include <linux/buffer_head.h> | |
21 | #include <linux/bio.h> | |
546e0d27 | 22 | #include <linux/blkdev.h> |
61159a31 RW |
23 | #include <linux/swap.h> |
24 | #include <linux/swapops.h> | |
25 | #include <linux/pm.h> | |
26 | ||
27 | #include "power.h" | |
28 | ||
61159a31 RW |
29 | #define SWSUSP_SIG "S1SUSPEND" |
30 | ||
1b29c164 | 31 | struct swsusp_header { |
a634cc10 | 32 | char reserved[PAGE_SIZE - 20 - sizeof(sector_t) - sizeof(int)]; |
3aef83e0 | 33 | sector_t image; |
a634cc10 | 34 | unsigned int flags; /* Flags to pass to the "boot" kernel */ |
61159a31 RW |
35 | char orig_sig[10]; |
36 | char sig[10]; | |
1b29c164 VG |
37 | } __attribute__((packed)); |
38 | ||
39 | static struct swsusp_header *swsusp_header; | |
61159a31 | 40 | |
0414f2ec NC |
41 | /** |
42 | * The following functions are used for tracing the allocated | |
43 | * swap pages, so that they can be freed in case of an error. | |
44 | */ | |
45 | ||
46 | struct swsusp_extent { | |
47 | struct rb_node node; | |
48 | unsigned long start; | |
49 | unsigned long end; | |
50 | }; | |
51 | ||
52 | static struct rb_root swsusp_extents = RB_ROOT; | |
53 | ||
54 | static int swsusp_extents_insert(unsigned long swap_offset) | |
55 | { | |
56 | struct rb_node **new = &(swsusp_extents.rb_node); | |
57 | struct rb_node *parent = NULL; | |
58 | struct swsusp_extent *ext; | |
59 | ||
60 | /* Figure out where to put the new node */ | |
61 | while (*new) { | |
62 | ext = container_of(*new, struct swsusp_extent, node); | |
63 | parent = *new; | |
64 | if (swap_offset < ext->start) { | |
65 | /* Try to merge */ | |
66 | if (swap_offset == ext->start - 1) { | |
67 | ext->start--; | |
68 | return 0; | |
69 | } | |
70 | new = &((*new)->rb_left); | |
71 | } else if (swap_offset > ext->end) { | |
72 | /* Try to merge */ | |
73 | if (swap_offset == ext->end + 1) { | |
74 | ext->end++; | |
75 | return 0; | |
76 | } | |
77 | new = &((*new)->rb_right); | |
78 | } else { | |
79 | /* It already is in the tree */ | |
80 | return -EINVAL; | |
81 | } | |
82 | } | |
83 | /* Add the new node and rebalance the tree. */ | |
84 | ext = kzalloc(sizeof(struct swsusp_extent), GFP_KERNEL); | |
85 | if (!ext) | |
86 | return -ENOMEM; | |
87 | ||
88 | ext->start = swap_offset; | |
89 | ext->end = swap_offset; | |
90 | rb_link_node(&ext->node, parent, new); | |
91 | rb_insert_color(&ext->node, &swsusp_extents); | |
92 | return 0; | |
93 | } | |
94 | ||
95 | /** | |
96 | * alloc_swapdev_block - allocate a swap page and register that it has | |
97 | * been allocated, so that it can be freed in case of an error. | |
98 | */ | |
99 | ||
100 | sector_t alloc_swapdev_block(int swap) | |
101 | { | |
102 | unsigned long offset; | |
103 | ||
104 | offset = swp_offset(get_swap_page_of_type(swap)); | |
105 | if (offset) { | |
106 | if (swsusp_extents_insert(offset)) | |
107 | swap_free(swp_entry(swap, offset)); | |
108 | else | |
109 | return swapdev_block(swap, offset); | |
110 | } | |
111 | return 0; | |
112 | } | |
113 | ||
114 | /** | |
115 | * free_all_swap_pages - free swap pages allocated for saving image data. | |
116 | * It also frees the extents used to register which swap entres had been | |
117 | * allocated. | |
118 | */ | |
119 | ||
120 | void free_all_swap_pages(int swap) | |
121 | { | |
122 | struct rb_node *node; | |
123 | ||
124 | while ((node = swsusp_extents.rb_node)) { | |
125 | struct swsusp_extent *ext; | |
126 | unsigned long offset; | |
127 | ||
128 | ext = container_of(node, struct swsusp_extent, node); | |
129 | rb_erase(node, &swsusp_extents); | |
130 | for (offset = ext->start; offset <= ext->end; offset++) | |
131 | swap_free(swp_entry(swap, offset)); | |
132 | ||
133 | kfree(ext); | |
134 | } | |
135 | } | |
136 | ||
137 | int swsusp_swap_in_use(void) | |
138 | { | |
139 | return (swsusp_extents.rb_node != NULL); | |
140 | } | |
141 | ||
61159a31 | 142 | /* |
3fc6b34f | 143 | * General things |
61159a31 RW |
144 | */ |
145 | ||
146 | static unsigned short root_swap = 0xffff; | |
3fc6b34f RW |
147 | static struct block_device *resume_bdev; |
148 | ||
149 | /** | |
150 | * submit - submit BIO request. | |
151 | * @rw: READ or WRITE. | |
152 | * @off physical offset of page. | |
153 | * @page: page we're reading or writing. | |
154 | * @bio_chain: list of pending biod (for async reading) | |
155 | * | |
156 | * Straight from the textbook - allocate and initialize the bio. | |
157 | * If we're reading, make sure the page is marked as dirty. | |
158 | * Then submit it and, if @bio_chain == NULL, wait. | |
159 | */ | |
160 | static int submit(int rw, pgoff_t page_off, struct page *page, | |
161 | struct bio **bio_chain) | |
162 | { | |
93dbb393 | 163 | const int bio_rw = rw | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG); |
3fc6b34f RW |
164 | struct bio *bio; |
165 | ||
85949121 | 166 | bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1); |
3fc6b34f RW |
167 | bio->bi_sector = page_off * (PAGE_SIZE >> 9); |
168 | bio->bi_bdev = resume_bdev; | |
169 | bio->bi_end_io = end_swap_bio_read; | |
170 | ||
171 | if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) { | |
23976728 RW |
172 | printk(KERN_ERR "PM: Adding page to bio failed at %ld\n", |
173 | page_off); | |
3fc6b34f RW |
174 | bio_put(bio); |
175 | return -EFAULT; | |
176 | } | |
177 | ||
178 | lock_page(page); | |
179 | bio_get(bio); | |
180 | ||
181 | if (bio_chain == NULL) { | |
93dbb393 | 182 | submit_bio(bio_rw, bio); |
3fc6b34f RW |
183 | wait_on_page_locked(page); |
184 | if (rw == READ) | |
185 | bio_set_pages_dirty(bio); | |
186 | bio_put(bio); | |
187 | } else { | |
188 | if (rw == READ) | |
189 | get_page(page); /* These pages are freed later */ | |
190 | bio->bi_private = *bio_chain; | |
191 | *bio_chain = bio; | |
93dbb393 | 192 | submit_bio(bio_rw, bio); |
3fc6b34f RW |
193 | } |
194 | return 0; | |
195 | } | |
196 | ||
197 | static int bio_read_page(pgoff_t page_off, void *addr, struct bio **bio_chain) | |
198 | { | |
199 | return submit(READ, page_off, virt_to_page(addr), bio_chain); | |
200 | } | |
201 | ||
3aef83e0 | 202 | static int bio_write_page(pgoff_t page_off, void *addr, struct bio **bio_chain) |
3fc6b34f | 203 | { |
3aef83e0 | 204 | return submit(WRITE, page_off, virt_to_page(addr), bio_chain); |
3fc6b34f RW |
205 | } |
206 | ||
207 | static int wait_on_bio_chain(struct bio **bio_chain) | |
208 | { | |
209 | struct bio *bio; | |
210 | struct bio *next_bio; | |
211 | int ret = 0; | |
212 | ||
213 | if (bio_chain == NULL) | |
214 | return 0; | |
215 | ||
216 | bio = *bio_chain; | |
217 | if (bio == NULL) | |
218 | return 0; | |
219 | while (bio) { | |
220 | struct page *page; | |
221 | ||
222 | next_bio = bio->bi_private; | |
223 | page = bio->bi_io_vec[0].bv_page; | |
224 | wait_on_page_locked(page); | |
225 | if (!PageUptodate(page) || PageError(page)) | |
226 | ret = -EIO; | |
227 | put_page(page); | |
228 | bio_put(bio); | |
229 | bio = next_bio; | |
230 | } | |
231 | *bio_chain = NULL; | |
232 | return ret; | |
233 | } | |
234 | ||
3fc6b34f RW |
235 | /* |
236 | * Saving part | |
237 | */ | |
61159a31 | 238 | |
a634cc10 | 239 | static int mark_swapfiles(sector_t start, unsigned int flags) |
61159a31 RW |
240 | { |
241 | int error; | |
242 | ||
1b29c164 VG |
243 | bio_read_page(swsusp_resume_block, swsusp_header, NULL); |
244 | if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) || | |
245 | !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) { | |
246 | memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10); | |
247 | memcpy(swsusp_header->sig,SWSUSP_SIG, 10); | |
248 | swsusp_header->image = start; | |
a634cc10 | 249 | swsusp_header->flags = flags; |
9a154d9d | 250 | error = bio_write_page(swsusp_resume_block, |
1b29c164 | 251 | swsusp_header, NULL); |
61159a31 | 252 | } else { |
23976728 | 253 | printk(KERN_ERR "PM: Swap header not found!\n"); |
61159a31 RW |
254 | error = -ENODEV; |
255 | } | |
256 | return error; | |
257 | } | |
258 | ||
259 | /** | |
260 | * swsusp_swap_check - check if the resume device is a swap device | |
261 | * and get its index (if so) | |
262 | */ | |
263 | ||
264 | static int swsusp_swap_check(void) /* This is called before saving image */ | |
265 | { | |
3aef83e0 RW |
266 | int res; |
267 | ||
7bf23687 RW |
268 | res = swap_type_of(swsusp_resume_device, swsusp_resume_block, |
269 | &resume_bdev); | |
3aef83e0 RW |
270 | if (res < 0) |
271 | return res; | |
272 | ||
273 | root_swap = res; | |
572c4892 | 274 | res = blkdev_get(resume_bdev, FMODE_WRITE); |
7bf23687 RW |
275 | if (res) |
276 | return res; | |
3aef83e0 RW |
277 | |
278 | res = set_blocksize(resume_bdev, PAGE_SIZE); | |
279 | if (res < 0) | |
9a1c3542 | 280 | blkdev_put(resume_bdev, FMODE_WRITE); |
61159a31 | 281 | |
61159a31 RW |
282 | return res; |
283 | } | |
284 | ||
285 | /** | |
286 | * write_page - Write one page to given swap location. | |
287 | * @buf: Address we're writing. | |
288 | * @offset: Offset of the swap page we're writing to. | |
ab954160 | 289 | * @bio_chain: Link the next write BIO here |
61159a31 RW |
290 | */ |
291 | ||
3aef83e0 | 292 | static int write_page(void *buf, sector_t offset, struct bio **bio_chain) |
61159a31 | 293 | { |
3aef83e0 RW |
294 | void *src; |
295 | ||
296 | if (!offset) | |
297 | return -ENOSPC; | |
298 | ||
299 | if (bio_chain) { | |
85949121 | 300 | src = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH); |
3aef83e0 RW |
301 | if (src) { |
302 | memcpy(src, buf, PAGE_SIZE); | |
303 | } else { | |
304 | WARN_ON_ONCE(1); | |
305 | bio_chain = NULL; /* Go synchronous */ | |
306 | src = buf; | |
ab954160 | 307 | } |
3aef83e0 RW |
308 | } else { |
309 | src = buf; | |
61159a31 | 310 | } |
3aef83e0 | 311 | return bio_write_page(offset, src, bio_chain); |
61159a31 RW |
312 | } |
313 | ||
314 | /* | |
315 | * The swap map is a data structure used for keeping track of each page | |
316 | * written to a swap partition. It consists of many swap_map_page | |
317 | * structures that contain each an array of MAP_PAGE_SIZE swap entries. | |
318 | * These structures are stored on the swap and linked together with the | |
319 | * help of the .next_swap member. | |
320 | * | |
321 | * The swap map is created during suspend. The swap map pages are | |
322 | * allocated and populated one at a time, so we only need one memory | |
323 | * page to set up the entire structure. | |
324 | * | |
325 | * During resume we also only need to use one swap_map_page structure | |
326 | * at a time. | |
327 | */ | |
328 | ||
3aef83e0 | 329 | #define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(sector_t) - 1) |
61159a31 RW |
330 | |
331 | struct swap_map_page { | |
3aef83e0 RW |
332 | sector_t entries[MAP_PAGE_ENTRIES]; |
333 | sector_t next_swap; | |
61159a31 RW |
334 | }; |
335 | ||
336 | /** | |
337 | * The swap_map_handle structure is used for handling swap in | |
338 | * a file-alike way | |
339 | */ | |
340 | ||
341 | struct swap_map_handle { | |
342 | struct swap_map_page *cur; | |
3aef83e0 | 343 | sector_t cur_swap; |
61159a31 RW |
344 | unsigned int k; |
345 | }; | |
346 | ||
347 | static void release_swap_writer(struct swap_map_handle *handle) | |
348 | { | |
349 | if (handle->cur) | |
350 | free_page((unsigned long)handle->cur); | |
351 | handle->cur = NULL; | |
61159a31 RW |
352 | } |
353 | ||
354 | static int get_swap_writer(struct swap_map_handle *handle) | |
355 | { | |
356 | handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL); | |
357 | if (!handle->cur) | |
358 | return -ENOMEM; | |
d1d241cc | 359 | handle->cur_swap = alloc_swapdev_block(root_swap); |
61159a31 RW |
360 | if (!handle->cur_swap) { |
361 | release_swap_writer(handle); | |
362 | return -ENOSPC; | |
363 | } | |
364 | handle->k = 0; | |
365 | return 0; | |
366 | } | |
367 | ||
ab954160 AM |
368 | static int swap_write_page(struct swap_map_handle *handle, void *buf, |
369 | struct bio **bio_chain) | |
370 | { | |
371 | int error = 0; | |
3aef83e0 | 372 | sector_t offset; |
61159a31 RW |
373 | |
374 | if (!handle->cur) | |
375 | return -EINVAL; | |
d1d241cc | 376 | offset = alloc_swapdev_block(root_swap); |
ab954160 | 377 | error = write_page(buf, offset, bio_chain); |
61159a31 RW |
378 | if (error) |
379 | return error; | |
380 | handle->cur->entries[handle->k++] = offset; | |
381 | if (handle->k >= MAP_PAGE_ENTRIES) { | |
ab954160 AM |
382 | error = wait_on_bio_chain(bio_chain); |
383 | if (error) | |
384 | goto out; | |
d1d241cc | 385 | offset = alloc_swapdev_block(root_swap); |
61159a31 RW |
386 | if (!offset) |
387 | return -ENOSPC; | |
388 | handle->cur->next_swap = offset; | |
ab954160 | 389 | error = write_page(handle->cur, handle->cur_swap, NULL); |
61159a31 | 390 | if (error) |
ab954160 | 391 | goto out; |
61159a31 RW |
392 | memset(handle->cur, 0, PAGE_SIZE); |
393 | handle->cur_swap = offset; | |
394 | handle->k = 0; | |
395 | } | |
59a49335 | 396 | out: |
ab954160 | 397 | return error; |
61159a31 RW |
398 | } |
399 | ||
400 | static int flush_swap_writer(struct swap_map_handle *handle) | |
401 | { | |
402 | if (handle->cur && handle->cur_swap) | |
ab954160 | 403 | return write_page(handle->cur, handle->cur_swap, NULL); |
61159a31 RW |
404 | else |
405 | return -EINVAL; | |
406 | } | |
407 | ||
408 | /** | |
409 | * save_image - save the suspend image data | |
410 | */ | |
411 | ||
412 | static int save_image(struct swap_map_handle *handle, | |
413 | struct snapshot_handle *snapshot, | |
3a4f7577 | 414 | unsigned int nr_to_write) |
61159a31 RW |
415 | { |
416 | unsigned int m; | |
417 | int ret; | |
3a4f7577 | 418 | int nr_pages; |
ab954160 AM |
419 | int err2; |
420 | struct bio *bio; | |
3a4f7577 AM |
421 | struct timeval start; |
422 | struct timeval stop; | |
61159a31 | 423 | |
23976728 RW |
424 | printk(KERN_INFO "PM: Saving image data pages (%u pages) ... ", |
425 | nr_to_write); | |
3a4f7577 | 426 | m = nr_to_write / 100; |
61159a31 RW |
427 | if (!m) |
428 | m = 1; | |
429 | nr_pages = 0; | |
ab954160 | 430 | bio = NULL; |
3a4f7577 | 431 | do_gettimeofday(&start); |
4ff277f9 | 432 | while (1) { |
61159a31 | 433 | ret = snapshot_read_next(snapshot, PAGE_SIZE); |
4ff277f9 JS |
434 | if (ret <= 0) |
435 | break; | |
436 | ret = swap_write_page(handle, data_of(*snapshot), &bio); | |
437 | if (ret) | |
438 | break; | |
439 | if (!(nr_pages % m)) | |
66d0ae4d | 440 | printk(KERN_CONT "\b\b\b\b%3d%%", nr_pages / m); |
4ff277f9 JS |
441 | nr_pages++; |
442 | } | |
ab954160 | 443 | err2 = wait_on_bio_chain(&bio); |
3a4f7577 | 444 | do_gettimeofday(&stop); |
4ff277f9 JS |
445 | if (!ret) |
446 | ret = err2; | |
447 | if (!ret) | |
66d0ae4d | 448 | printk(KERN_CONT "\b\b\b\bdone\n"); |
4ff277f9 | 449 | else |
66d0ae4d | 450 | printk(KERN_CONT "\n"); |
0d3a9abe | 451 | swsusp_show_speed(&start, &stop, nr_to_write, "Wrote"); |
4ff277f9 | 452 | return ret; |
61159a31 RW |
453 | } |
454 | ||
455 | /** | |
456 | * enough_swap - Make sure we have enough swap to save the image. | |
457 | * | |
458 | * Returns TRUE or FALSE after checking the total amount of swap | |
459 | * space avaiable from the resume partition. | |
460 | */ | |
461 | ||
462 | static int enough_swap(unsigned int nr_pages) | |
463 | { | |
464 | unsigned int free_swap = count_swap_pages(root_swap, 1); | |
465 | ||
23976728 | 466 | pr_debug("PM: Free swap pages: %u\n", free_swap); |
940864dd | 467 | return free_swap > nr_pages + PAGES_FOR_IO; |
61159a31 RW |
468 | } |
469 | ||
470 | /** | |
471 | * swsusp_write - Write entire image and metadata. | |
a634cc10 | 472 | * @flags: flags to pass to the "boot" kernel in the image header |
61159a31 RW |
473 | * |
474 | * It is important _NOT_ to umount filesystems at this point. We want | |
475 | * them synced (in case something goes wrong) but we DO not want to mark | |
476 | * filesystem clean: it is not. (And it does not matter, if we resume | |
477 | * correctly, we'll mark system clean, anyway.) | |
478 | */ | |
479 | ||
a634cc10 | 480 | int swsusp_write(unsigned int flags) |
61159a31 RW |
481 | { |
482 | struct swap_map_handle handle; | |
483 | struct snapshot_handle snapshot; | |
484 | struct swsusp_info *header; | |
61159a31 RW |
485 | int error; |
486 | ||
3aef83e0 RW |
487 | error = swsusp_swap_check(); |
488 | if (error) { | |
23976728 | 489 | printk(KERN_ERR "PM: Cannot find swap device, try " |
546e0d27 | 490 | "swapon -a.\n"); |
61159a31 RW |
491 | return error; |
492 | } | |
493 | memset(&snapshot, 0, sizeof(struct snapshot_handle)); | |
494 | error = snapshot_read_next(&snapshot, PAGE_SIZE); | |
3aef83e0 RW |
495 | if (error < PAGE_SIZE) { |
496 | if (error >= 0) | |
497 | error = -EFAULT; | |
498 | ||
499 | goto out; | |
500 | } | |
61159a31 RW |
501 | header = (struct swsusp_info *)data_of(snapshot); |
502 | if (!enough_swap(header->pages)) { | |
23976728 | 503 | printk(KERN_ERR "PM: Not enough free swap\n"); |
3aef83e0 RW |
504 | error = -ENOSPC; |
505 | goto out; | |
61159a31 RW |
506 | } |
507 | error = get_swap_writer(&handle); | |
508 | if (!error) { | |
3aef83e0 RW |
509 | sector_t start = handle.cur_swap; |
510 | ||
ab954160 | 511 | error = swap_write_page(&handle, header, NULL); |
712f403a AM |
512 | if (!error) |
513 | error = save_image(&handle, &snapshot, | |
514 | header->pages - 1); | |
3aef83e0 | 515 | |
712f403a AM |
516 | if (!error) { |
517 | flush_swap_writer(&handle); | |
23976728 | 518 | printk(KERN_INFO "PM: S"); |
a634cc10 | 519 | error = mark_swapfiles(start, flags); |
712f403a AM |
520 | printk("|\n"); |
521 | } | |
61159a31 RW |
522 | } |
523 | if (error) | |
d1d241cc RW |
524 | free_all_swap_pages(root_swap); |
525 | ||
61159a31 | 526 | release_swap_writer(&handle); |
59a49335 | 527 | out: |
c2dd0dae | 528 | swsusp_close(FMODE_WRITE); |
61159a31 RW |
529 | return error; |
530 | } | |
531 | ||
61159a31 RW |
532 | /** |
533 | * The following functions allow us to read data using a swap map | |
534 | * in a file-alike way | |
535 | */ | |
536 | ||
537 | static void release_swap_reader(struct swap_map_handle *handle) | |
538 | { | |
539 | if (handle->cur) | |
540 | free_page((unsigned long)handle->cur); | |
541 | handle->cur = NULL; | |
542 | } | |
543 | ||
3aef83e0 | 544 | static int get_swap_reader(struct swap_map_handle *handle, sector_t start) |
61159a31 RW |
545 | { |
546 | int error; | |
547 | ||
3aef83e0 | 548 | if (!start) |
61159a31 | 549 | return -EINVAL; |
3aef83e0 | 550 | |
85949121 | 551 | handle->cur = (struct swap_map_page *)get_zeroed_page(__GFP_WAIT | __GFP_HIGH); |
61159a31 RW |
552 | if (!handle->cur) |
553 | return -ENOMEM; | |
3aef83e0 RW |
554 | |
555 | error = bio_read_page(start, handle->cur, NULL); | |
61159a31 RW |
556 | if (error) { |
557 | release_swap_reader(handle); | |
558 | return error; | |
559 | } | |
560 | handle->k = 0; | |
561 | return 0; | |
562 | } | |
563 | ||
546e0d27 AM |
564 | static int swap_read_page(struct swap_map_handle *handle, void *buf, |
565 | struct bio **bio_chain) | |
61159a31 | 566 | { |
3aef83e0 | 567 | sector_t offset; |
61159a31 RW |
568 | int error; |
569 | ||
570 | if (!handle->cur) | |
571 | return -EINVAL; | |
572 | offset = handle->cur->entries[handle->k]; | |
573 | if (!offset) | |
574 | return -EFAULT; | |
546e0d27 | 575 | error = bio_read_page(offset, buf, bio_chain); |
61159a31 RW |
576 | if (error) |
577 | return error; | |
578 | if (++handle->k >= MAP_PAGE_ENTRIES) { | |
546e0d27 | 579 | error = wait_on_bio_chain(bio_chain); |
61159a31 RW |
580 | handle->k = 0; |
581 | offset = handle->cur->next_swap; | |
582 | if (!offset) | |
583 | release_swap_reader(handle); | |
546e0d27 AM |
584 | else if (!error) |
585 | error = bio_read_page(offset, handle->cur, NULL); | |
61159a31 RW |
586 | } |
587 | return error; | |
588 | } | |
589 | ||
590 | /** | |
591 | * load_image - load the image using the swap map handle | |
592 | * @handle and the snapshot handle @snapshot | |
593 | * (assume there are @nr_pages pages to load) | |
594 | */ | |
595 | ||
596 | static int load_image(struct swap_map_handle *handle, | |
597 | struct snapshot_handle *snapshot, | |
546e0d27 | 598 | unsigned int nr_to_read) |
61159a31 RW |
599 | { |
600 | unsigned int m; | |
61159a31 | 601 | int error = 0; |
8c002494 AM |
602 | struct timeval start; |
603 | struct timeval stop; | |
546e0d27 AM |
604 | struct bio *bio; |
605 | int err2; | |
606 | unsigned nr_pages; | |
61159a31 | 607 | |
23976728 RW |
608 | printk(KERN_INFO "PM: Loading image data pages (%u pages) ... ", |
609 | nr_to_read); | |
546e0d27 | 610 | m = nr_to_read / 100; |
61159a31 RW |
611 | if (!m) |
612 | m = 1; | |
613 | nr_pages = 0; | |
546e0d27 | 614 | bio = NULL; |
8c002494 | 615 | do_gettimeofday(&start); |
546e0d27 AM |
616 | for ( ; ; ) { |
617 | error = snapshot_write_next(snapshot, PAGE_SIZE); | |
618 | if (error <= 0) | |
619 | break; | |
620 | error = swap_read_page(handle, data_of(*snapshot), &bio); | |
621 | if (error) | |
622 | break; | |
623 | if (snapshot->sync_read) | |
624 | error = wait_on_bio_chain(&bio); | |
625 | if (error) | |
626 | break; | |
627 | if (!(nr_pages % m)) | |
628 | printk("\b\b\b\b%3d%%", nr_pages / m); | |
629 | nr_pages++; | |
630 | } | |
631 | err2 = wait_on_bio_chain(&bio); | |
8c002494 | 632 | do_gettimeofday(&stop); |
546e0d27 AM |
633 | if (!error) |
634 | error = err2; | |
e655a250 | 635 | if (!error) { |
61159a31 | 636 | printk("\b\b\b\bdone\n"); |
8357376d | 637 | snapshot_write_finalize(snapshot); |
e655a250 CK |
638 | if (!snapshot_image_loaded(snapshot)) |
639 | error = -ENODATA; | |
bf9fd67a JS |
640 | } else |
641 | printk("\n"); | |
0d3a9abe | 642 | swsusp_show_speed(&start, &stop, nr_to_read, "Read"); |
61159a31 RW |
643 | return error; |
644 | } | |
645 | ||
a634cc10 RW |
646 | /** |
647 | * swsusp_read - read the hibernation image. | |
648 | * @flags_p: flags passed by the "frozen" kernel in the image header should | |
649 | * be written into this memeory location | |
650 | */ | |
651 | ||
652 | int swsusp_read(unsigned int *flags_p) | |
61159a31 RW |
653 | { |
654 | int error; | |
655 | struct swap_map_handle handle; | |
656 | struct snapshot_handle snapshot; | |
657 | struct swsusp_info *header; | |
658 | ||
a634cc10 | 659 | *flags_p = swsusp_header->flags; |
61159a31 RW |
660 | |
661 | memset(&snapshot, 0, sizeof(struct snapshot_handle)); | |
662 | error = snapshot_write_next(&snapshot, PAGE_SIZE); | |
663 | if (error < PAGE_SIZE) | |
664 | return error < 0 ? error : -EFAULT; | |
665 | header = (struct swsusp_info *)data_of(snapshot); | |
1b29c164 | 666 | error = get_swap_reader(&handle, swsusp_header->image); |
61159a31 | 667 | if (!error) |
546e0d27 | 668 | error = swap_read_page(&handle, header, NULL); |
61159a31 RW |
669 | if (!error) |
670 | error = load_image(&handle, &snapshot, header->pages - 1); | |
671 | release_swap_reader(&handle); | |
672 | ||
61159a31 | 673 | if (!error) |
23976728 | 674 | pr_debug("PM: Image successfully loaded\n"); |
61159a31 | 675 | else |
23976728 | 676 | pr_debug("PM: Error %d resuming\n", error); |
61159a31 RW |
677 | return error; |
678 | } | |
679 | ||
680 | /** | |
681 | * swsusp_check - Check for swsusp signature in the resume device | |
682 | */ | |
683 | ||
684 | int swsusp_check(void) | |
685 | { | |
686 | int error; | |
687 | ||
688 | resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ); | |
689 | if (!IS_ERR(resume_bdev)) { | |
690 | set_blocksize(resume_bdev, PAGE_SIZE); | |
6373da1f | 691 | memset(swsusp_header, 0, PAGE_SIZE); |
9a154d9d | 692 | error = bio_read_page(swsusp_resume_block, |
1b29c164 | 693 | swsusp_header, NULL); |
9a154d9d | 694 | if (error) |
76b57e61 | 695 | goto put; |
9a154d9d | 696 | |
1b29c164 VG |
697 | if (!memcmp(SWSUSP_SIG, swsusp_header->sig, 10)) { |
698 | memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10); | |
61159a31 | 699 | /* Reset swap signature now */ |
9a154d9d | 700 | error = bio_write_page(swsusp_resume_block, |
1b29c164 | 701 | swsusp_header, NULL); |
61159a31 | 702 | } else { |
76b57e61 | 703 | error = -EINVAL; |
61159a31 | 704 | } |
76b57e61 JS |
705 | |
706 | put: | |
61159a31 | 707 | if (error) |
9a1c3542 | 708 | blkdev_put(resume_bdev, FMODE_READ); |
61159a31 | 709 | else |
23976728 | 710 | pr_debug("PM: Signature found, resuming\n"); |
61159a31 RW |
711 | } else { |
712 | error = PTR_ERR(resume_bdev); | |
713 | } | |
714 | ||
715 | if (error) | |
23976728 | 716 | pr_debug("PM: Error %d checking image file\n", error); |
61159a31 RW |
717 | |
718 | return error; | |
719 | } | |
720 | ||
721 | /** | |
722 | * swsusp_close - close swap device. | |
723 | */ | |
724 | ||
c2dd0dae | 725 | void swsusp_close(fmode_t mode) |
61159a31 RW |
726 | { |
727 | if (IS_ERR(resume_bdev)) { | |
23976728 | 728 | pr_debug("PM: Image device not initialised\n"); |
61159a31 RW |
729 | return; |
730 | } | |
731 | ||
50c396d3 | 732 | blkdev_put(resume_bdev, mode); |
61159a31 | 733 | } |
1b29c164 VG |
734 | |
735 | static int swsusp_header_init(void) | |
736 | { | |
737 | swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL); | |
738 | if (!swsusp_header) | |
739 | panic("Could not allocate memory for swsusp_header\n"); | |
740 | return 0; | |
741 | } | |
742 | ||
743 | core_initcall(swsusp_header_init); |