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Commit | Line | Data |
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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> | |
5a0e3ad6 | 26 | #include <linux/slab.h> |
61159a31 RW |
27 | |
28 | #include "power.h" | |
29 | ||
61159a31 RW |
30 | #define SWSUSP_SIG "S1SUSPEND" |
31 | ||
1b29c164 | 32 | struct swsusp_header { |
a634cc10 | 33 | char reserved[PAGE_SIZE - 20 - sizeof(sector_t) - sizeof(int)]; |
3aef83e0 | 34 | sector_t image; |
a634cc10 | 35 | unsigned int flags; /* Flags to pass to the "boot" kernel */ |
61159a31 RW |
36 | char orig_sig[10]; |
37 | char sig[10]; | |
1b29c164 VG |
38 | } __attribute__((packed)); |
39 | ||
40 | static struct swsusp_header *swsusp_header; | |
61159a31 | 41 | |
0414f2ec NC |
42 | /** |
43 | * The following functions are used for tracing the allocated | |
44 | * swap pages, so that they can be freed in case of an error. | |
45 | */ | |
46 | ||
47 | struct swsusp_extent { | |
48 | struct rb_node node; | |
49 | unsigned long start; | |
50 | unsigned long end; | |
51 | }; | |
52 | ||
53 | static struct rb_root swsusp_extents = RB_ROOT; | |
54 | ||
55 | static int swsusp_extents_insert(unsigned long swap_offset) | |
56 | { | |
57 | struct rb_node **new = &(swsusp_extents.rb_node); | |
58 | struct rb_node *parent = NULL; | |
59 | struct swsusp_extent *ext; | |
60 | ||
61 | /* Figure out where to put the new node */ | |
62 | while (*new) { | |
63 | ext = container_of(*new, struct swsusp_extent, node); | |
64 | parent = *new; | |
65 | if (swap_offset < ext->start) { | |
66 | /* Try to merge */ | |
67 | if (swap_offset == ext->start - 1) { | |
68 | ext->start--; | |
69 | return 0; | |
70 | } | |
71 | new = &((*new)->rb_left); | |
72 | } else if (swap_offset > ext->end) { | |
73 | /* Try to merge */ | |
74 | if (swap_offset == ext->end + 1) { | |
75 | ext->end++; | |
76 | return 0; | |
77 | } | |
78 | new = &((*new)->rb_right); | |
79 | } else { | |
80 | /* It already is in the tree */ | |
81 | return -EINVAL; | |
82 | } | |
83 | } | |
84 | /* Add the new node and rebalance the tree. */ | |
85 | ext = kzalloc(sizeof(struct swsusp_extent), GFP_KERNEL); | |
86 | if (!ext) | |
87 | return -ENOMEM; | |
88 | ||
89 | ext->start = swap_offset; | |
90 | ext->end = swap_offset; | |
91 | rb_link_node(&ext->node, parent, new); | |
92 | rb_insert_color(&ext->node, &swsusp_extents); | |
93 | return 0; | |
94 | } | |
95 | ||
96 | /** | |
97 | * alloc_swapdev_block - allocate a swap page and register that it has | |
98 | * been allocated, so that it can be freed in case of an error. | |
99 | */ | |
100 | ||
101 | sector_t alloc_swapdev_block(int swap) | |
102 | { | |
103 | unsigned long offset; | |
104 | ||
105 | offset = swp_offset(get_swap_page_of_type(swap)); | |
106 | if (offset) { | |
107 | if (swsusp_extents_insert(offset)) | |
108 | swap_free(swp_entry(swap, offset)); | |
109 | else | |
110 | return swapdev_block(swap, offset); | |
111 | } | |
112 | return 0; | |
113 | } | |
114 | ||
115 | /** | |
116 | * free_all_swap_pages - free swap pages allocated for saving image data. | |
117 | * It also frees the extents used to register which swap entres had been | |
118 | * allocated. | |
119 | */ | |
120 | ||
121 | void free_all_swap_pages(int swap) | |
122 | { | |
123 | struct rb_node *node; | |
124 | ||
125 | while ((node = swsusp_extents.rb_node)) { | |
126 | struct swsusp_extent *ext; | |
127 | unsigned long offset; | |
128 | ||
129 | ext = container_of(node, struct swsusp_extent, node); | |
130 | rb_erase(node, &swsusp_extents); | |
131 | for (offset = ext->start; offset <= ext->end; offset++) | |
132 | swap_free(swp_entry(swap, offset)); | |
133 | ||
134 | kfree(ext); | |
135 | } | |
136 | } | |
137 | ||
138 | int swsusp_swap_in_use(void) | |
139 | { | |
140 | return (swsusp_extents.rb_node != NULL); | |
141 | } | |
142 | ||
61159a31 | 143 | /* |
3fc6b34f | 144 | * General things |
61159a31 RW |
145 | */ |
146 | ||
147 | static unsigned short root_swap = 0xffff; | |
3fc6b34f RW |
148 | static struct block_device *resume_bdev; |
149 | ||
150 | /** | |
151 | * submit - submit BIO request. | |
152 | * @rw: READ or WRITE. | |
153 | * @off physical offset of page. | |
154 | * @page: page we're reading or writing. | |
155 | * @bio_chain: list of pending biod (for async reading) | |
156 | * | |
157 | * Straight from the textbook - allocate and initialize the bio. | |
158 | * If we're reading, make sure the page is marked as dirty. | |
159 | * Then submit it and, if @bio_chain == NULL, wait. | |
160 | */ | |
161 | static int submit(int rw, pgoff_t page_off, struct page *page, | |
162 | struct bio **bio_chain) | |
163 | { | |
93dbb393 | 164 | const int bio_rw = rw | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG); |
3fc6b34f RW |
165 | struct bio *bio; |
166 | ||
85949121 | 167 | bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1); |
3fc6b34f RW |
168 | bio->bi_sector = page_off * (PAGE_SIZE >> 9); |
169 | bio->bi_bdev = resume_bdev; | |
170 | bio->bi_end_io = end_swap_bio_read; | |
171 | ||
172 | if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) { | |
23976728 RW |
173 | printk(KERN_ERR "PM: Adding page to bio failed at %ld\n", |
174 | page_off); | |
3fc6b34f RW |
175 | bio_put(bio); |
176 | return -EFAULT; | |
177 | } | |
178 | ||
179 | lock_page(page); | |
180 | bio_get(bio); | |
181 | ||
182 | if (bio_chain == NULL) { | |
93dbb393 | 183 | submit_bio(bio_rw, bio); |
3fc6b34f RW |
184 | wait_on_page_locked(page); |
185 | if (rw == READ) | |
186 | bio_set_pages_dirty(bio); | |
187 | bio_put(bio); | |
188 | } else { | |
189 | if (rw == READ) | |
190 | get_page(page); /* These pages are freed later */ | |
191 | bio->bi_private = *bio_chain; | |
192 | *bio_chain = bio; | |
93dbb393 | 193 | submit_bio(bio_rw, bio); |
3fc6b34f RW |
194 | } |
195 | return 0; | |
196 | } | |
197 | ||
198 | static int bio_read_page(pgoff_t page_off, void *addr, struct bio **bio_chain) | |
199 | { | |
200 | return submit(READ, page_off, virt_to_page(addr), bio_chain); | |
201 | } | |
202 | ||
3aef83e0 | 203 | static int bio_write_page(pgoff_t page_off, void *addr, struct bio **bio_chain) |
3fc6b34f | 204 | { |
3aef83e0 | 205 | return submit(WRITE, page_off, virt_to_page(addr), bio_chain); |
3fc6b34f RW |
206 | } |
207 | ||
208 | static int wait_on_bio_chain(struct bio **bio_chain) | |
209 | { | |
210 | struct bio *bio; | |
211 | struct bio *next_bio; | |
212 | int ret = 0; | |
213 | ||
214 | if (bio_chain == NULL) | |
215 | return 0; | |
216 | ||
217 | bio = *bio_chain; | |
218 | if (bio == NULL) | |
219 | return 0; | |
220 | while (bio) { | |
221 | struct page *page; | |
222 | ||
223 | next_bio = bio->bi_private; | |
224 | page = bio->bi_io_vec[0].bv_page; | |
225 | wait_on_page_locked(page); | |
226 | if (!PageUptodate(page) || PageError(page)) | |
227 | ret = -EIO; | |
228 | put_page(page); | |
229 | bio_put(bio); | |
230 | bio = next_bio; | |
231 | } | |
232 | *bio_chain = NULL; | |
233 | return ret; | |
234 | } | |
235 | ||
3fc6b34f RW |
236 | /* |
237 | * Saving part | |
238 | */ | |
61159a31 | 239 | |
a634cc10 | 240 | static int mark_swapfiles(sector_t start, unsigned int flags) |
61159a31 RW |
241 | { |
242 | int error; | |
243 | ||
1b29c164 VG |
244 | bio_read_page(swsusp_resume_block, swsusp_header, NULL); |
245 | if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) || | |
246 | !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) { | |
247 | memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10); | |
248 | memcpy(swsusp_header->sig,SWSUSP_SIG, 10); | |
249 | swsusp_header->image = start; | |
a634cc10 | 250 | swsusp_header->flags = flags; |
9a154d9d | 251 | error = bio_write_page(swsusp_resume_block, |
1b29c164 | 252 | swsusp_header, NULL); |
61159a31 | 253 | } else { |
23976728 | 254 | printk(KERN_ERR "PM: Swap header not found!\n"); |
61159a31 RW |
255 | error = -ENODEV; |
256 | } | |
257 | return error; | |
258 | } | |
259 | ||
260 | /** | |
261 | * swsusp_swap_check - check if the resume device is a swap device | |
262 | * and get its index (if so) | |
263 | */ | |
264 | ||
265 | static int swsusp_swap_check(void) /* This is called before saving image */ | |
266 | { | |
3aef83e0 RW |
267 | int res; |
268 | ||
7bf23687 RW |
269 | res = swap_type_of(swsusp_resume_device, swsusp_resume_block, |
270 | &resume_bdev); | |
3aef83e0 RW |
271 | if (res < 0) |
272 | return res; | |
273 | ||
274 | root_swap = res; | |
572c4892 | 275 | res = blkdev_get(resume_bdev, FMODE_WRITE); |
7bf23687 RW |
276 | if (res) |
277 | return res; | |
3aef83e0 RW |
278 | |
279 | res = set_blocksize(resume_bdev, PAGE_SIZE); | |
280 | if (res < 0) | |
9a1c3542 | 281 | blkdev_put(resume_bdev, FMODE_WRITE); |
61159a31 | 282 | |
61159a31 RW |
283 | return res; |
284 | } | |
285 | ||
286 | /** | |
287 | * write_page - Write one page to given swap location. | |
288 | * @buf: Address we're writing. | |
289 | * @offset: Offset of the swap page we're writing to. | |
ab954160 | 290 | * @bio_chain: Link the next write BIO here |
61159a31 RW |
291 | */ |
292 | ||
3aef83e0 | 293 | static int write_page(void *buf, sector_t offset, struct bio **bio_chain) |
61159a31 | 294 | { |
3aef83e0 RW |
295 | void *src; |
296 | ||
297 | if (!offset) | |
298 | return -ENOSPC; | |
299 | ||
300 | if (bio_chain) { | |
85949121 | 301 | src = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH); |
3aef83e0 RW |
302 | if (src) { |
303 | memcpy(src, buf, PAGE_SIZE); | |
304 | } else { | |
305 | WARN_ON_ONCE(1); | |
306 | bio_chain = NULL; /* Go synchronous */ | |
307 | src = buf; | |
ab954160 | 308 | } |
3aef83e0 RW |
309 | } else { |
310 | src = buf; | |
61159a31 | 311 | } |
3aef83e0 | 312 | return bio_write_page(offset, src, bio_chain); |
61159a31 RW |
313 | } |
314 | ||
315 | /* | |
316 | * The swap map is a data structure used for keeping track of each page | |
317 | * written to a swap partition. It consists of many swap_map_page | |
318 | * structures that contain each an array of MAP_PAGE_SIZE swap entries. | |
319 | * These structures are stored on the swap and linked together with the | |
320 | * help of the .next_swap member. | |
321 | * | |
322 | * The swap map is created during suspend. The swap map pages are | |
323 | * allocated and populated one at a time, so we only need one memory | |
324 | * page to set up the entire structure. | |
325 | * | |
326 | * During resume we also only need to use one swap_map_page structure | |
327 | * at a time. | |
328 | */ | |
329 | ||
3aef83e0 | 330 | #define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(sector_t) - 1) |
61159a31 RW |
331 | |
332 | struct swap_map_page { | |
3aef83e0 RW |
333 | sector_t entries[MAP_PAGE_ENTRIES]; |
334 | sector_t next_swap; | |
61159a31 RW |
335 | }; |
336 | ||
337 | /** | |
338 | * The swap_map_handle structure is used for handling swap in | |
339 | * a file-alike way | |
340 | */ | |
341 | ||
342 | struct swap_map_handle { | |
343 | struct swap_map_page *cur; | |
3aef83e0 | 344 | sector_t cur_swap; |
61159a31 RW |
345 | unsigned int k; |
346 | }; | |
347 | ||
348 | static void release_swap_writer(struct swap_map_handle *handle) | |
349 | { | |
350 | if (handle->cur) | |
351 | free_page((unsigned long)handle->cur); | |
352 | handle->cur = NULL; | |
61159a31 RW |
353 | } |
354 | ||
355 | static int get_swap_writer(struct swap_map_handle *handle) | |
356 | { | |
357 | handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL); | |
358 | if (!handle->cur) | |
359 | return -ENOMEM; | |
d1d241cc | 360 | handle->cur_swap = alloc_swapdev_block(root_swap); |
61159a31 RW |
361 | if (!handle->cur_swap) { |
362 | release_swap_writer(handle); | |
363 | return -ENOSPC; | |
364 | } | |
365 | handle->k = 0; | |
366 | return 0; | |
367 | } | |
368 | ||
ab954160 AM |
369 | static int swap_write_page(struct swap_map_handle *handle, void *buf, |
370 | struct bio **bio_chain) | |
371 | { | |
372 | int error = 0; | |
3aef83e0 | 373 | sector_t offset; |
61159a31 RW |
374 | |
375 | if (!handle->cur) | |
376 | return -EINVAL; | |
d1d241cc | 377 | offset = alloc_swapdev_block(root_swap); |
ab954160 | 378 | error = write_page(buf, offset, bio_chain); |
61159a31 RW |
379 | if (error) |
380 | return error; | |
381 | handle->cur->entries[handle->k++] = offset; | |
382 | if (handle->k >= MAP_PAGE_ENTRIES) { | |
ab954160 AM |
383 | error = wait_on_bio_chain(bio_chain); |
384 | if (error) | |
385 | goto out; | |
d1d241cc | 386 | offset = alloc_swapdev_block(root_swap); |
61159a31 RW |
387 | if (!offset) |
388 | return -ENOSPC; | |
389 | handle->cur->next_swap = offset; | |
ab954160 | 390 | error = write_page(handle->cur, handle->cur_swap, NULL); |
61159a31 | 391 | if (error) |
ab954160 | 392 | goto out; |
61159a31 RW |
393 | memset(handle->cur, 0, PAGE_SIZE); |
394 | handle->cur_swap = offset; | |
395 | handle->k = 0; | |
396 | } | |
59a49335 | 397 | out: |
ab954160 | 398 | return error; |
61159a31 RW |
399 | } |
400 | ||
401 | static int flush_swap_writer(struct swap_map_handle *handle) | |
402 | { | |
403 | if (handle->cur && handle->cur_swap) | |
ab954160 | 404 | return write_page(handle->cur, handle->cur_swap, NULL); |
61159a31 RW |
405 | else |
406 | return -EINVAL; | |
407 | } | |
408 | ||
409 | /** | |
410 | * save_image - save the suspend image data | |
411 | */ | |
412 | ||
413 | static int save_image(struct swap_map_handle *handle, | |
414 | struct snapshot_handle *snapshot, | |
3a4f7577 | 415 | unsigned int nr_to_write) |
61159a31 RW |
416 | { |
417 | unsigned int m; | |
418 | int ret; | |
3a4f7577 | 419 | int nr_pages; |
ab954160 AM |
420 | int err2; |
421 | struct bio *bio; | |
3a4f7577 AM |
422 | struct timeval start; |
423 | struct timeval stop; | |
61159a31 | 424 | |
23976728 RW |
425 | printk(KERN_INFO "PM: Saving image data pages (%u pages) ... ", |
426 | nr_to_write); | |
3a4f7577 | 427 | m = nr_to_write / 100; |
61159a31 RW |
428 | if (!m) |
429 | m = 1; | |
430 | nr_pages = 0; | |
ab954160 | 431 | bio = NULL; |
3a4f7577 | 432 | do_gettimeofday(&start); |
4ff277f9 | 433 | while (1) { |
61159a31 | 434 | ret = snapshot_read_next(snapshot, PAGE_SIZE); |
4ff277f9 JS |
435 | if (ret <= 0) |
436 | break; | |
437 | ret = swap_write_page(handle, data_of(*snapshot), &bio); | |
438 | if (ret) | |
439 | break; | |
440 | if (!(nr_pages % m)) | |
66d0ae4d | 441 | printk(KERN_CONT "\b\b\b\b%3d%%", nr_pages / m); |
4ff277f9 JS |
442 | nr_pages++; |
443 | } | |
ab954160 | 444 | err2 = wait_on_bio_chain(&bio); |
3a4f7577 | 445 | do_gettimeofday(&stop); |
4ff277f9 JS |
446 | if (!ret) |
447 | ret = err2; | |
448 | if (!ret) | |
66d0ae4d | 449 | printk(KERN_CONT "\b\b\b\bdone\n"); |
4ff277f9 | 450 | else |
66d0ae4d | 451 | printk(KERN_CONT "\n"); |
0d3a9abe | 452 | swsusp_show_speed(&start, &stop, nr_to_write, "Wrote"); |
4ff277f9 | 453 | return ret; |
61159a31 RW |
454 | } |
455 | ||
456 | /** | |
457 | * enough_swap - Make sure we have enough swap to save the image. | |
458 | * | |
459 | * Returns TRUE or FALSE after checking the total amount of swap | |
460 | * space avaiable from the resume partition. | |
461 | */ | |
462 | ||
463 | static int enough_swap(unsigned int nr_pages) | |
464 | { | |
465 | unsigned int free_swap = count_swap_pages(root_swap, 1); | |
466 | ||
23976728 | 467 | pr_debug("PM: Free swap pages: %u\n", free_swap); |
940864dd | 468 | return free_swap > nr_pages + PAGES_FOR_IO; |
61159a31 RW |
469 | } |
470 | ||
471 | /** | |
472 | * swsusp_write - Write entire image and metadata. | |
a634cc10 | 473 | * @flags: flags to pass to the "boot" kernel in the image header |
61159a31 RW |
474 | * |
475 | * It is important _NOT_ to umount filesystems at this point. We want | |
476 | * them synced (in case something goes wrong) but we DO not want to mark | |
477 | * filesystem clean: it is not. (And it does not matter, if we resume | |
478 | * correctly, we'll mark system clean, anyway.) | |
479 | */ | |
480 | ||
a634cc10 | 481 | int swsusp_write(unsigned int flags) |
61159a31 RW |
482 | { |
483 | struct swap_map_handle handle; | |
484 | struct snapshot_handle snapshot; | |
485 | struct swsusp_info *header; | |
61159a31 RW |
486 | int error; |
487 | ||
3aef83e0 RW |
488 | error = swsusp_swap_check(); |
489 | if (error) { | |
23976728 | 490 | printk(KERN_ERR "PM: Cannot find swap device, try " |
546e0d27 | 491 | "swapon -a.\n"); |
61159a31 RW |
492 | return error; |
493 | } | |
494 | memset(&snapshot, 0, sizeof(struct snapshot_handle)); | |
495 | error = snapshot_read_next(&snapshot, PAGE_SIZE); | |
3aef83e0 RW |
496 | if (error < PAGE_SIZE) { |
497 | if (error >= 0) | |
498 | error = -EFAULT; | |
499 | ||
500 | goto out; | |
501 | } | |
61159a31 RW |
502 | header = (struct swsusp_info *)data_of(snapshot); |
503 | if (!enough_swap(header->pages)) { | |
23976728 | 504 | printk(KERN_ERR "PM: Not enough free swap\n"); |
3aef83e0 RW |
505 | error = -ENOSPC; |
506 | goto out; | |
61159a31 RW |
507 | } |
508 | error = get_swap_writer(&handle); | |
509 | if (!error) { | |
3aef83e0 RW |
510 | sector_t start = handle.cur_swap; |
511 | ||
ab954160 | 512 | error = swap_write_page(&handle, header, NULL); |
712f403a AM |
513 | if (!error) |
514 | error = save_image(&handle, &snapshot, | |
515 | header->pages - 1); | |
3aef83e0 | 516 | |
712f403a AM |
517 | if (!error) { |
518 | flush_swap_writer(&handle); | |
23976728 | 519 | printk(KERN_INFO "PM: S"); |
a634cc10 | 520 | error = mark_swapfiles(start, flags); |
712f403a AM |
521 | printk("|\n"); |
522 | } | |
61159a31 RW |
523 | } |
524 | if (error) | |
d1d241cc RW |
525 | free_all_swap_pages(root_swap); |
526 | ||
61159a31 | 527 | release_swap_writer(&handle); |
59a49335 | 528 | out: |
c2dd0dae | 529 | swsusp_close(FMODE_WRITE); |
61159a31 RW |
530 | return error; |
531 | } | |
532 | ||
61159a31 RW |
533 | /** |
534 | * The following functions allow us to read data using a swap map | |
535 | * in a file-alike way | |
536 | */ | |
537 | ||
538 | static void release_swap_reader(struct swap_map_handle *handle) | |
539 | { | |
540 | if (handle->cur) | |
541 | free_page((unsigned long)handle->cur); | |
542 | handle->cur = NULL; | |
543 | } | |
544 | ||
3aef83e0 | 545 | static int get_swap_reader(struct swap_map_handle *handle, sector_t start) |
61159a31 RW |
546 | { |
547 | int error; | |
548 | ||
3aef83e0 | 549 | if (!start) |
61159a31 | 550 | return -EINVAL; |
3aef83e0 | 551 | |
85949121 | 552 | handle->cur = (struct swap_map_page *)get_zeroed_page(__GFP_WAIT | __GFP_HIGH); |
61159a31 RW |
553 | if (!handle->cur) |
554 | return -ENOMEM; | |
3aef83e0 RW |
555 | |
556 | error = bio_read_page(start, handle->cur, NULL); | |
61159a31 RW |
557 | if (error) { |
558 | release_swap_reader(handle); | |
559 | return error; | |
560 | } | |
561 | handle->k = 0; | |
562 | return 0; | |
563 | } | |
564 | ||
546e0d27 AM |
565 | static int swap_read_page(struct swap_map_handle *handle, void *buf, |
566 | struct bio **bio_chain) | |
61159a31 | 567 | { |
3aef83e0 | 568 | sector_t offset; |
61159a31 RW |
569 | int error; |
570 | ||
571 | if (!handle->cur) | |
572 | return -EINVAL; | |
573 | offset = handle->cur->entries[handle->k]; | |
574 | if (!offset) | |
575 | return -EFAULT; | |
546e0d27 | 576 | error = bio_read_page(offset, buf, bio_chain); |
61159a31 RW |
577 | if (error) |
578 | return error; | |
579 | if (++handle->k >= MAP_PAGE_ENTRIES) { | |
546e0d27 | 580 | error = wait_on_bio_chain(bio_chain); |
61159a31 RW |
581 | handle->k = 0; |
582 | offset = handle->cur->next_swap; | |
583 | if (!offset) | |
584 | release_swap_reader(handle); | |
546e0d27 AM |
585 | else if (!error) |
586 | error = bio_read_page(offset, handle->cur, NULL); | |
61159a31 RW |
587 | } |
588 | return error; | |
589 | } | |
590 | ||
591 | /** | |
592 | * load_image - load the image using the swap map handle | |
593 | * @handle and the snapshot handle @snapshot | |
594 | * (assume there are @nr_pages pages to load) | |
595 | */ | |
596 | ||
597 | static int load_image(struct swap_map_handle *handle, | |
598 | struct snapshot_handle *snapshot, | |
546e0d27 | 599 | unsigned int nr_to_read) |
61159a31 RW |
600 | { |
601 | unsigned int m; | |
61159a31 | 602 | int error = 0; |
8c002494 AM |
603 | struct timeval start; |
604 | struct timeval stop; | |
546e0d27 AM |
605 | struct bio *bio; |
606 | int err2; | |
607 | unsigned nr_pages; | |
61159a31 | 608 | |
23976728 RW |
609 | printk(KERN_INFO "PM: Loading image data pages (%u pages) ... ", |
610 | nr_to_read); | |
546e0d27 | 611 | m = nr_to_read / 100; |
61159a31 RW |
612 | if (!m) |
613 | m = 1; | |
614 | nr_pages = 0; | |
546e0d27 | 615 | bio = NULL; |
8c002494 | 616 | do_gettimeofday(&start); |
546e0d27 AM |
617 | for ( ; ; ) { |
618 | error = snapshot_write_next(snapshot, PAGE_SIZE); | |
619 | if (error <= 0) | |
620 | break; | |
621 | error = swap_read_page(handle, data_of(*snapshot), &bio); | |
622 | if (error) | |
623 | break; | |
624 | if (snapshot->sync_read) | |
625 | error = wait_on_bio_chain(&bio); | |
626 | if (error) | |
627 | break; | |
628 | if (!(nr_pages % m)) | |
629 | printk("\b\b\b\b%3d%%", nr_pages / m); | |
630 | nr_pages++; | |
631 | } | |
632 | err2 = wait_on_bio_chain(&bio); | |
8c002494 | 633 | do_gettimeofday(&stop); |
546e0d27 AM |
634 | if (!error) |
635 | error = err2; | |
e655a250 | 636 | if (!error) { |
61159a31 | 637 | printk("\b\b\b\bdone\n"); |
8357376d | 638 | snapshot_write_finalize(snapshot); |
e655a250 CK |
639 | if (!snapshot_image_loaded(snapshot)) |
640 | error = -ENODATA; | |
bf9fd67a JS |
641 | } else |
642 | printk("\n"); | |
0d3a9abe | 643 | swsusp_show_speed(&start, &stop, nr_to_read, "Read"); |
61159a31 RW |
644 | return error; |
645 | } | |
646 | ||
a634cc10 RW |
647 | /** |
648 | * swsusp_read - read the hibernation image. | |
649 | * @flags_p: flags passed by the "frozen" kernel in the image header should | |
650 | * be written into this memeory location | |
651 | */ | |
652 | ||
653 | int swsusp_read(unsigned int *flags_p) | |
61159a31 RW |
654 | { |
655 | int error; | |
656 | struct swap_map_handle handle; | |
657 | struct snapshot_handle snapshot; | |
658 | struct swsusp_info *header; | |
659 | ||
a634cc10 | 660 | *flags_p = swsusp_header->flags; |
61159a31 RW |
661 | |
662 | memset(&snapshot, 0, sizeof(struct snapshot_handle)); | |
663 | error = snapshot_write_next(&snapshot, PAGE_SIZE); | |
664 | if (error < PAGE_SIZE) | |
665 | return error < 0 ? error : -EFAULT; | |
666 | header = (struct swsusp_info *)data_of(snapshot); | |
1b29c164 | 667 | error = get_swap_reader(&handle, swsusp_header->image); |
61159a31 | 668 | if (!error) |
546e0d27 | 669 | error = swap_read_page(&handle, header, NULL); |
61159a31 RW |
670 | if (!error) |
671 | error = load_image(&handle, &snapshot, header->pages - 1); | |
672 | release_swap_reader(&handle); | |
673 | ||
61159a31 | 674 | if (!error) |
23976728 | 675 | pr_debug("PM: Image successfully loaded\n"); |
61159a31 | 676 | else |
23976728 | 677 | pr_debug("PM: Error %d resuming\n", error); |
61159a31 RW |
678 | return error; |
679 | } | |
680 | ||
681 | /** | |
682 | * swsusp_check - Check for swsusp signature in the resume device | |
683 | */ | |
684 | ||
685 | int swsusp_check(void) | |
686 | { | |
687 | int error; | |
688 | ||
689 | resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ); | |
690 | if (!IS_ERR(resume_bdev)) { | |
691 | set_blocksize(resume_bdev, PAGE_SIZE); | |
6373da1f | 692 | memset(swsusp_header, 0, PAGE_SIZE); |
9a154d9d | 693 | error = bio_read_page(swsusp_resume_block, |
1b29c164 | 694 | swsusp_header, NULL); |
9a154d9d | 695 | if (error) |
76b57e61 | 696 | goto put; |
9a154d9d | 697 | |
1b29c164 VG |
698 | if (!memcmp(SWSUSP_SIG, swsusp_header->sig, 10)) { |
699 | memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10); | |
61159a31 | 700 | /* Reset swap signature now */ |
9a154d9d | 701 | error = bio_write_page(swsusp_resume_block, |
1b29c164 | 702 | swsusp_header, NULL); |
61159a31 | 703 | } else { |
76b57e61 | 704 | error = -EINVAL; |
61159a31 | 705 | } |
76b57e61 JS |
706 | |
707 | put: | |
61159a31 | 708 | if (error) |
9a1c3542 | 709 | blkdev_put(resume_bdev, FMODE_READ); |
61159a31 | 710 | else |
23976728 | 711 | pr_debug("PM: Signature found, resuming\n"); |
61159a31 RW |
712 | } else { |
713 | error = PTR_ERR(resume_bdev); | |
714 | } | |
715 | ||
716 | if (error) | |
23976728 | 717 | pr_debug("PM: Error %d checking image file\n", error); |
61159a31 RW |
718 | |
719 | return error; | |
720 | } | |
721 | ||
722 | /** | |
723 | * swsusp_close - close swap device. | |
724 | */ | |
725 | ||
c2dd0dae | 726 | void swsusp_close(fmode_t mode) |
61159a31 RW |
727 | { |
728 | if (IS_ERR(resume_bdev)) { | |
23976728 | 729 | pr_debug("PM: Image device not initialised\n"); |
61159a31 RW |
730 | return; |
731 | } | |
732 | ||
50c396d3 | 733 | blkdev_put(resume_bdev, mode); |
61159a31 | 734 | } |
1b29c164 VG |
735 | |
736 | static int swsusp_header_init(void) | |
737 | { | |
738 | swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL); | |
739 | if (!swsusp_header) | |
740 | panic("Could not allocate memory for swsusp_header\n"); | |
741 | return 0; | |
742 | } | |
743 | ||
744 | core_initcall(swsusp_header_init); |