Commit | Line | Data |
---|---|---|
25761b6e | 1 | /* |
96bc7aec | 2 | * linux/kernel/power/snapshot.c |
25761b6e | 3 | * |
8357376d | 4 | * This file provides system snapshot/restore functionality for swsusp. |
25761b6e RW |
5 | * |
6 | * Copyright (C) 1998-2005 Pavel Machek <pavel@suse.cz> | |
8357376d | 7 | * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl> |
25761b6e | 8 | * |
8357376d | 9 | * This file is released under the GPLv2. |
25761b6e RW |
10 | * |
11 | */ | |
12 | ||
f577eb30 | 13 | #include <linux/version.h> |
25761b6e RW |
14 | #include <linux/module.h> |
15 | #include <linux/mm.h> | |
16 | #include <linux/suspend.h> | |
25761b6e | 17 | #include <linux/delay.h> |
25761b6e | 18 | #include <linux/bitops.h> |
25761b6e | 19 | #include <linux/spinlock.h> |
25761b6e | 20 | #include <linux/kernel.h> |
25761b6e RW |
21 | #include <linux/pm.h> |
22 | #include <linux/device.h> | |
74dfd666 | 23 | #include <linux/init.h> |
25761b6e RW |
24 | #include <linux/bootmem.h> |
25 | #include <linux/syscalls.h> | |
26 | #include <linux/console.h> | |
27 | #include <linux/highmem.h> | |
846705de | 28 | #include <linux/list.h> |
25761b6e RW |
29 | |
30 | #include <asm/uaccess.h> | |
31 | #include <asm/mmu_context.h> | |
32 | #include <asm/pgtable.h> | |
33 | #include <asm/tlbflush.h> | |
34 | #include <asm/io.h> | |
35 | ||
25761b6e RW |
36 | #include "power.h" |
37 | ||
74dfd666 RW |
38 | static int swsusp_page_is_free(struct page *); |
39 | static void swsusp_set_page_forbidden(struct page *); | |
40 | static void swsusp_unset_page_forbidden(struct page *); | |
41 | ||
fe419535 RW |
42 | /* |
43 | * Preferred image size in bytes (tunable via /sys/power/image_size). | |
44 | * When it is set to N, swsusp will do its best to ensure the image | |
45 | * size will not exceed N bytes, but if that is impossible, it will | |
46 | * try to create the smallest image possible. | |
47 | */ | |
48 | unsigned long image_size = 500 * 1024 * 1024; | |
49 | ||
8357376d RW |
50 | /* List of PBEs needed for restoring the pages that were allocated before |
51 | * the suspend and included in the suspend image, but have also been | |
52 | * allocated by the "resume" kernel, so their contents cannot be written | |
53 | * directly to their "original" page frames. | |
54 | */ | |
75534b50 RW |
55 | struct pbe *restore_pblist; |
56 | ||
8357376d | 57 | /* Pointer to an auxiliary buffer (1 page) */ |
940864dd | 58 | static void *buffer; |
7088a5c0 | 59 | |
f6143aa6 RW |
60 | /** |
61 | * @safe_needed - on resume, for storing the PBE list and the image, | |
62 | * we can only use memory pages that do not conflict with the pages | |
8357376d RW |
63 | * used before suspend. The unsafe pages have PageNosaveFree set |
64 | * and we count them using unsafe_pages. | |
f6143aa6 | 65 | * |
8357376d RW |
66 | * Each allocated image page is marked as PageNosave and PageNosaveFree |
67 | * so that swsusp_free() can release it. | |
f6143aa6 RW |
68 | */ |
69 | ||
0bcd888d RW |
70 | #define PG_ANY 0 |
71 | #define PG_SAFE 1 | |
72 | #define PG_UNSAFE_CLEAR 1 | |
73 | #define PG_UNSAFE_KEEP 0 | |
74 | ||
940864dd | 75 | static unsigned int allocated_unsafe_pages; |
f6143aa6 | 76 | |
8357376d | 77 | static void *get_image_page(gfp_t gfp_mask, int safe_needed) |
f6143aa6 RW |
78 | { |
79 | void *res; | |
80 | ||
81 | res = (void *)get_zeroed_page(gfp_mask); | |
82 | if (safe_needed) | |
7be98234 | 83 | while (res && swsusp_page_is_free(virt_to_page(res))) { |
f6143aa6 | 84 | /* The page is unsafe, mark it for swsusp_free() */ |
7be98234 | 85 | swsusp_set_page_forbidden(virt_to_page(res)); |
940864dd | 86 | allocated_unsafe_pages++; |
f6143aa6 RW |
87 | res = (void *)get_zeroed_page(gfp_mask); |
88 | } | |
89 | if (res) { | |
7be98234 RW |
90 | swsusp_set_page_forbidden(virt_to_page(res)); |
91 | swsusp_set_page_free(virt_to_page(res)); | |
f6143aa6 RW |
92 | } |
93 | return res; | |
94 | } | |
95 | ||
96 | unsigned long get_safe_page(gfp_t gfp_mask) | |
97 | { | |
8357376d RW |
98 | return (unsigned long)get_image_page(gfp_mask, PG_SAFE); |
99 | } | |
100 | ||
5b6d15de RW |
101 | static struct page *alloc_image_page(gfp_t gfp_mask) |
102 | { | |
8357376d RW |
103 | struct page *page; |
104 | ||
105 | page = alloc_page(gfp_mask); | |
106 | if (page) { | |
7be98234 RW |
107 | swsusp_set_page_forbidden(page); |
108 | swsusp_set_page_free(page); | |
8357376d RW |
109 | } |
110 | return page; | |
f6143aa6 RW |
111 | } |
112 | ||
113 | /** | |
114 | * free_image_page - free page represented by @addr, allocated with | |
8357376d | 115 | * get_image_page (page flags set by it must be cleared) |
f6143aa6 RW |
116 | */ |
117 | ||
118 | static inline void free_image_page(void *addr, int clear_nosave_free) | |
119 | { | |
8357376d RW |
120 | struct page *page; |
121 | ||
122 | BUG_ON(!virt_addr_valid(addr)); | |
123 | ||
124 | page = virt_to_page(addr); | |
125 | ||
7be98234 | 126 | swsusp_unset_page_forbidden(page); |
f6143aa6 | 127 | if (clear_nosave_free) |
7be98234 | 128 | swsusp_unset_page_free(page); |
8357376d RW |
129 | |
130 | __free_page(page); | |
f6143aa6 RW |
131 | } |
132 | ||
b788db79 RW |
133 | /* struct linked_page is used to build chains of pages */ |
134 | ||
135 | #define LINKED_PAGE_DATA_SIZE (PAGE_SIZE - sizeof(void *)) | |
136 | ||
137 | struct linked_page { | |
138 | struct linked_page *next; | |
139 | char data[LINKED_PAGE_DATA_SIZE]; | |
140 | } __attribute__((packed)); | |
141 | ||
142 | static inline void | |
143 | free_list_of_pages(struct linked_page *list, int clear_page_nosave) | |
144 | { | |
145 | while (list) { | |
146 | struct linked_page *lp = list->next; | |
147 | ||
148 | free_image_page(list, clear_page_nosave); | |
149 | list = lp; | |
150 | } | |
151 | } | |
152 | ||
153 | /** | |
154 | * struct chain_allocator is used for allocating small objects out of | |
155 | * a linked list of pages called 'the chain'. | |
156 | * | |
157 | * The chain grows each time when there is no room for a new object in | |
158 | * the current page. The allocated objects cannot be freed individually. | |
159 | * It is only possible to free them all at once, by freeing the entire | |
160 | * chain. | |
161 | * | |
162 | * NOTE: The chain allocator may be inefficient if the allocated objects | |
163 | * are not much smaller than PAGE_SIZE. | |
164 | */ | |
165 | ||
166 | struct chain_allocator { | |
167 | struct linked_page *chain; /* the chain */ | |
168 | unsigned int used_space; /* total size of objects allocated out | |
169 | * of the current page | |
170 | */ | |
171 | gfp_t gfp_mask; /* mask for allocating pages */ | |
172 | int safe_needed; /* if set, only "safe" pages are allocated */ | |
173 | }; | |
174 | ||
175 | static void | |
176 | chain_init(struct chain_allocator *ca, gfp_t gfp_mask, int safe_needed) | |
177 | { | |
178 | ca->chain = NULL; | |
179 | ca->used_space = LINKED_PAGE_DATA_SIZE; | |
180 | ca->gfp_mask = gfp_mask; | |
181 | ca->safe_needed = safe_needed; | |
182 | } | |
183 | ||
184 | static void *chain_alloc(struct chain_allocator *ca, unsigned int size) | |
185 | { | |
186 | void *ret; | |
187 | ||
188 | if (LINKED_PAGE_DATA_SIZE - ca->used_space < size) { | |
189 | struct linked_page *lp; | |
190 | ||
8357376d | 191 | lp = get_image_page(ca->gfp_mask, ca->safe_needed); |
b788db79 RW |
192 | if (!lp) |
193 | return NULL; | |
194 | ||
195 | lp->next = ca->chain; | |
196 | ca->chain = lp; | |
197 | ca->used_space = 0; | |
198 | } | |
199 | ret = ca->chain->data + ca->used_space; | |
200 | ca->used_space += size; | |
201 | return ret; | |
202 | } | |
203 | ||
b788db79 RW |
204 | /** |
205 | * Data types related to memory bitmaps. | |
206 | * | |
207 | * Memory bitmap is a structure consiting of many linked lists of | |
208 | * objects. The main list's elements are of type struct zone_bitmap | |
209 | * and each of them corresonds to one zone. For each zone bitmap | |
210 | * object there is a list of objects of type struct bm_block that | |
0d83304c | 211 | * represent each blocks of bitmap in which information is stored. |
b788db79 RW |
212 | * |
213 | * struct memory_bitmap contains a pointer to the main list of zone | |
214 | * bitmap objects, a struct bm_position used for browsing the bitmap, | |
215 | * and a pointer to the list of pages used for allocating all of the | |
216 | * zone bitmap objects and bitmap block objects. | |
217 | * | |
218 | * NOTE: It has to be possible to lay out the bitmap in memory | |
219 | * using only allocations of order 0. Additionally, the bitmap is | |
220 | * designed to work with arbitrary number of zones (this is over the | |
221 | * top for now, but let's avoid making unnecessary assumptions ;-). | |
222 | * | |
223 | * struct zone_bitmap contains a pointer to a list of bitmap block | |
224 | * objects and a pointer to the bitmap block object that has been | |
225 | * most recently used for setting bits. Additionally, it contains the | |
226 | * pfns that correspond to the start and end of the represented zone. | |
227 | * | |
228 | * struct bm_block contains a pointer to the memory page in which | |
0d83304c AM |
229 | * information is stored (in the form of a block of bitmap) |
230 | * It also contains the pfns that correspond to the start and end of | |
231 | * the represented memory area. | |
b788db79 RW |
232 | */ |
233 | ||
234 | #define BM_END_OF_MAP (~0UL) | |
235 | ||
b788db79 RW |
236 | #define BM_BITS_PER_BLOCK (PAGE_SIZE << 3) |
237 | ||
238 | struct bm_block { | |
846705de | 239 | struct list_head hook; /* hook into a list of bitmap blocks */ |
b788db79 RW |
240 | unsigned long start_pfn; /* pfn represented by the first bit */ |
241 | unsigned long end_pfn; /* pfn represented by the last bit plus 1 */ | |
0d83304c | 242 | unsigned long *data; /* bitmap representing pages */ |
b788db79 RW |
243 | }; |
244 | ||
0d83304c AM |
245 | static inline unsigned long bm_block_bits(struct bm_block *bb) |
246 | { | |
247 | return bb->end_pfn - bb->start_pfn; | |
248 | } | |
249 | ||
b788db79 RW |
250 | /* strcut bm_position is used for browsing memory bitmaps */ |
251 | ||
252 | struct bm_position { | |
b788db79 | 253 | struct bm_block *block; |
b788db79 RW |
254 | int bit; |
255 | }; | |
256 | ||
257 | struct memory_bitmap { | |
846705de | 258 | struct list_head blocks; /* list of bitmap blocks */ |
b788db79 RW |
259 | struct linked_page *p_list; /* list of pages used to store zone |
260 | * bitmap objects and bitmap block | |
261 | * objects | |
262 | */ | |
263 | struct bm_position cur; /* most recently used bit position */ | |
264 | }; | |
265 | ||
266 | /* Functions that operate on memory bitmaps */ | |
267 | ||
b788db79 RW |
268 | static void memory_bm_position_reset(struct memory_bitmap *bm) |
269 | { | |
846705de | 270 | bm->cur.block = list_entry(bm->blocks.next, struct bm_block, hook); |
0d83304c | 271 | bm->cur.bit = 0; |
b788db79 RW |
272 | } |
273 | ||
274 | static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free); | |
275 | ||
276 | /** | |
277 | * create_bm_block_list - create a list of block bitmap objects | |
846705de RW |
278 | * @nr_blocks - number of blocks to allocate |
279 | * @list - list to put the allocated blocks into | |
280 | * @ca - chain allocator to be used for allocating memory | |
b788db79 | 281 | */ |
846705de RW |
282 | static int create_bm_block_list(unsigned long pages, |
283 | struct list_head *list, | |
284 | struct chain_allocator *ca) | |
b788db79 | 285 | { |
846705de | 286 | unsigned int nr_blocks = DIV_ROUND_UP(pages, BM_BITS_PER_BLOCK); |
b788db79 RW |
287 | |
288 | while (nr_blocks-- > 0) { | |
289 | struct bm_block *bb; | |
290 | ||
291 | bb = chain_alloc(ca, sizeof(struct bm_block)); | |
292 | if (!bb) | |
846705de RW |
293 | return -ENOMEM; |
294 | list_add(&bb->hook, list); | |
b788db79 | 295 | } |
846705de RW |
296 | |
297 | return 0; | |
b788db79 RW |
298 | } |
299 | ||
846705de RW |
300 | struct mem_extent { |
301 | struct list_head hook; | |
302 | unsigned long start; | |
303 | unsigned long end; | |
304 | }; | |
305 | ||
b788db79 | 306 | /** |
846705de RW |
307 | * free_mem_extents - free a list of memory extents |
308 | * @list - list of extents to empty | |
b788db79 | 309 | */ |
846705de RW |
310 | static void free_mem_extents(struct list_head *list) |
311 | { | |
312 | struct mem_extent *ext, *aux; | |
b788db79 | 313 | |
846705de RW |
314 | list_for_each_entry_safe(ext, aux, list, hook) { |
315 | list_del(&ext->hook); | |
316 | kfree(ext); | |
317 | } | |
318 | } | |
319 | ||
320 | /** | |
321 | * create_mem_extents - create a list of memory extents representing | |
322 | * contiguous ranges of PFNs | |
323 | * @list - list to put the extents into | |
324 | * @gfp_mask - mask to use for memory allocations | |
325 | */ | |
326 | static int create_mem_extents(struct list_head *list, gfp_t gfp_mask) | |
b788db79 | 327 | { |
846705de | 328 | struct zone *zone; |
b788db79 | 329 | |
846705de | 330 | INIT_LIST_HEAD(list); |
b788db79 | 331 | |
ee99c71c | 332 | for_each_populated_zone(zone) { |
846705de RW |
333 | unsigned long zone_start, zone_end; |
334 | struct mem_extent *ext, *cur, *aux; | |
335 | ||
846705de RW |
336 | zone_start = zone->zone_start_pfn; |
337 | zone_end = zone->zone_start_pfn + zone->spanned_pages; | |
338 | ||
339 | list_for_each_entry(ext, list, hook) | |
340 | if (zone_start <= ext->end) | |
341 | break; | |
b788db79 | 342 | |
846705de RW |
343 | if (&ext->hook == list || zone_end < ext->start) { |
344 | /* New extent is necessary */ | |
345 | struct mem_extent *new_ext; | |
346 | ||
347 | new_ext = kzalloc(sizeof(struct mem_extent), gfp_mask); | |
348 | if (!new_ext) { | |
349 | free_mem_extents(list); | |
350 | return -ENOMEM; | |
351 | } | |
352 | new_ext->start = zone_start; | |
353 | new_ext->end = zone_end; | |
354 | list_add_tail(&new_ext->hook, &ext->hook); | |
355 | continue; | |
356 | } | |
357 | ||
358 | /* Merge this zone's range of PFNs with the existing one */ | |
359 | if (zone_start < ext->start) | |
360 | ext->start = zone_start; | |
361 | if (zone_end > ext->end) | |
362 | ext->end = zone_end; | |
363 | ||
364 | /* More merging may be possible */ | |
365 | cur = ext; | |
366 | list_for_each_entry_safe_continue(cur, aux, list, hook) { | |
367 | if (zone_end < cur->start) | |
368 | break; | |
369 | if (zone_end < cur->end) | |
370 | ext->end = cur->end; | |
371 | list_del(&cur->hook); | |
372 | kfree(cur); | |
373 | } | |
b788db79 | 374 | } |
846705de RW |
375 | |
376 | return 0; | |
b788db79 RW |
377 | } |
378 | ||
379 | /** | |
380 | * memory_bm_create - allocate memory for a memory bitmap | |
381 | */ | |
b788db79 RW |
382 | static int |
383 | memory_bm_create(struct memory_bitmap *bm, gfp_t gfp_mask, int safe_needed) | |
384 | { | |
385 | struct chain_allocator ca; | |
846705de RW |
386 | struct list_head mem_extents; |
387 | struct mem_extent *ext; | |
388 | int error; | |
b788db79 RW |
389 | |
390 | chain_init(&ca, gfp_mask, safe_needed); | |
846705de | 391 | INIT_LIST_HEAD(&bm->blocks); |
b788db79 | 392 | |
846705de RW |
393 | error = create_mem_extents(&mem_extents, gfp_mask); |
394 | if (error) | |
395 | return error; | |
b788db79 | 396 | |
846705de RW |
397 | list_for_each_entry(ext, &mem_extents, hook) { |
398 | struct bm_block *bb; | |
399 | unsigned long pfn = ext->start; | |
400 | unsigned long pages = ext->end - ext->start; | |
b788db79 | 401 | |
846705de | 402 | bb = list_entry(bm->blocks.prev, struct bm_block, hook); |
b788db79 | 403 | |
846705de RW |
404 | error = create_bm_block_list(pages, bm->blocks.prev, &ca); |
405 | if (error) | |
406 | goto Error; | |
b788db79 | 407 | |
846705de RW |
408 | list_for_each_entry_continue(bb, &bm->blocks, hook) { |
409 | bb->data = get_image_page(gfp_mask, safe_needed); | |
410 | if (!bb->data) { | |
411 | error = -ENOMEM; | |
412 | goto Error; | |
413 | } | |
b788db79 RW |
414 | |
415 | bb->start_pfn = pfn; | |
846705de | 416 | if (pages >= BM_BITS_PER_BLOCK) { |
b788db79 | 417 | pfn += BM_BITS_PER_BLOCK; |
846705de | 418 | pages -= BM_BITS_PER_BLOCK; |
b788db79 RW |
419 | } else { |
420 | /* This is executed only once in the loop */ | |
846705de | 421 | pfn += pages; |
b788db79 RW |
422 | } |
423 | bb->end_pfn = pfn; | |
b788db79 | 424 | } |
b788db79 | 425 | } |
846705de | 426 | |
b788db79 RW |
427 | bm->p_list = ca.chain; |
428 | memory_bm_position_reset(bm); | |
846705de RW |
429 | Exit: |
430 | free_mem_extents(&mem_extents); | |
431 | return error; | |
b788db79 | 432 | |
846705de | 433 | Error: |
b788db79 RW |
434 | bm->p_list = ca.chain; |
435 | memory_bm_free(bm, PG_UNSAFE_CLEAR); | |
846705de | 436 | goto Exit; |
b788db79 RW |
437 | } |
438 | ||
439 | /** | |
440 | * memory_bm_free - free memory occupied by the memory bitmap @bm | |
441 | */ | |
b788db79 RW |
442 | static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free) |
443 | { | |
846705de | 444 | struct bm_block *bb; |
b788db79 | 445 | |
846705de RW |
446 | list_for_each_entry(bb, &bm->blocks, hook) |
447 | if (bb->data) | |
448 | free_image_page(bb->data, clear_nosave_free); | |
b788db79 | 449 | |
b788db79 | 450 | free_list_of_pages(bm->p_list, clear_nosave_free); |
846705de RW |
451 | |
452 | INIT_LIST_HEAD(&bm->blocks); | |
b788db79 RW |
453 | } |
454 | ||
455 | /** | |
74dfd666 | 456 | * memory_bm_find_bit - find the bit in the bitmap @bm that corresponds |
b788db79 RW |
457 | * to given pfn. The cur_zone_bm member of @bm and the cur_block member |
458 | * of @bm->cur_zone_bm are updated. | |
b788db79 | 459 | */ |
a82f7119 | 460 | static int memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn, |
74dfd666 | 461 | void **addr, unsigned int *bit_nr) |
b788db79 | 462 | { |
b788db79 RW |
463 | struct bm_block *bb; |
464 | ||
846705de RW |
465 | /* |
466 | * Check if the pfn corresponds to the current bitmap block and find | |
467 | * the block where it fits if this is not the case. | |
468 | */ | |
469 | bb = bm->cur.block; | |
b788db79 | 470 | if (pfn < bb->start_pfn) |
846705de RW |
471 | list_for_each_entry_continue_reverse(bb, &bm->blocks, hook) |
472 | if (pfn >= bb->start_pfn) | |
473 | break; | |
b788db79 | 474 | |
846705de RW |
475 | if (pfn >= bb->end_pfn) |
476 | list_for_each_entry_continue(bb, &bm->blocks, hook) | |
477 | if (pfn >= bb->start_pfn && pfn < bb->end_pfn) | |
478 | break; | |
74dfd666 | 479 | |
846705de RW |
480 | if (&bb->hook == &bm->blocks) |
481 | return -EFAULT; | |
482 | ||
483 | /* The block has been found */ | |
484 | bm->cur.block = bb; | |
b788db79 | 485 | pfn -= bb->start_pfn; |
846705de | 486 | bm->cur.bit = pfn + 1; |
0d83304c AM |
487 | *bit_nr = pfn; |
488 | *addr = bb->data; | |
a82f7119 | 489 | return 0; |
74dfd666 RW |
490 | } |
491 | ||
492 | static void memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn) | |
493 | { | |
494 | void *addr; | |
495 | unsigned int bit; | |
a82f7119 | 496 | int error; |
74dfd666 | 497 | |
a82f7119 RW |
498 | error = memory_bm_find_bit(bm, pfn, &addr, &bit); |
499 | BUG_ON(error); | |
74dfd666 RW |
500 | set_bit(bit, addr); |
501 | } | |
502 | ||
a82f7119 RW |
503 | static int mem_bm_set_bit_check(struct memory_bitmap *bm, unsigned long pfn) |
504 | { | |
505 | void *addr; | |
506 | unsigned int bit; | |
507 | int error; | |
508 | ||
509 | error = memory_bm_find_bit(bm, pfn, &addr, &bit); | |
510 | if (!error) | |
511 | set_bit(bit, addr); | |
512 | return error; | |
513 | } | |
514 | ||
74dfd666 RW |
515 | static void memory_bm_clear_bit(struct memory_bitmap *bm, unsigned long pfn) |
516 | { | |
517 | void *addr; | |
518 | unsigned int bit; | |
a82f7119 | 519 | int error; |
74dfd666 | 520 | |
a82f7119 RW |
521 | error = memory_bm_find_bit(bm, pfn, &addr, &bit); |
522 | BUG_ON(error); | |
74dfd666 RW |
523 | clear_bit(bit, addr); |
524 | } | |
525 | ||
526 | static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn) | |
527 | { | |
528 | void *addr; | |
529 | unsigned int bit; | |
a82f7119 | 530 | int error; |
74dfd666 | 531 | |
a82f7119 RW |
532 | error = memory_bm_find_bit(bm, pfn, &addr, &bit); |
533 | BUG_ON(error); | |
74dfd666 | 534 | return test_bit(bit, addr); |
b788db79 RW |
535 | } |
536 | ||
69643279 RW |
537 | static bool memory_bm_pfn_present(struct memory_bitmap *bm, unsigned long pfn) |
538 | { | |
539 | void *addr; | |
540 | unsigned int bit; | |
541 | ||
542 | return !memory_bm_find_bit(bm, pfn, &addr, &bit); | |
543 | } | |
544 | ||
b788db79 RW |
545 | /** |
546 | * memory_bm_next_pfn - find the pfn that corresponds to the next set bit | |
547 | * in the bitmap @bm. If the pfn cannot be found, BM_END_OF_MAP is | |
548 | * returned. | |
549 | * | |
550 | * It is required to run memory_bm_position_reset() before the first call to | |
551 | * this function. | |
552 | */ | |
553 | ||
554 | static unsigned long memory_bm_next_pfn(struct memory_bitmap *bm) | |
555 | { | |
b788db79 | 556 | struct bm_block *bb; |
b788db79 RW |
557 | int bit; |
558 | ||
846705de | 559 | bb = bm->cur.block; |
b788db79 | 560 | do { |
846705de RW |
561 | bit = bm->cur.bit; |
562 | bit = find_next_bit(bb->data, bm_block_bits(bb), bit); | |
563 | if (bit < bm_block_bits(bb)) | |
564 | goto Return_pfn; | |
565 | ||
566 | bb = list_entry(bb->hook.next, struct bm_block, hook); | |
567 | bm->cur.block = bb; | |
568 | bm->cur.bit = 0; | |
569 | } while (&bb->hook != &bm->blocks); | |
570 | ||
b788db79 RW |
571 | memory_bm_position_reset(bm); |
572 | return BM_END_OF_MAP; | |
573 | ||
59a49335 | 574 | Return_pfn: |
0d83304c AM |
575 | bm->cur.bit = bit + 1; |
576 | return bb->start_pfn + bit; | |
b788db79 RW |
577 | } |
578 | ||
74dfd666 RW |
579 | /** |
580 | * This structure represents a range of page frames the contents of which | |
581 | * should not be saved during the suspend. | |
582 | */ | |
583 | ||
584 | struct nosave_region { | |
585 | struct list_head list; | |
586 | unsigned long start_pfn; | |
587 | unsigned long end_pfn; | |
588 | }; | |
589 | ||
590 | static LIST_HEAD(nosave_regions); | |
591 | ||
592 | /** | |
593 | * register_nosave_region - register a range of page frames the contents | |
594 | * of which should not be saved during the suspend (to be used in the early | |
595 | * initialization code) | |
596 | */ | |
597 | ||
598 | void __init | |
940d67f6 JB |
599 | __register_nosave_region(unsigned long start_pfn, unsigned long end_pfn, |
600 | int use_kmalloc) | |
74dfd666 RW |
601 | { |
602 | struct nosave_region *region; | |
603 | ||
604 | if (start_pfn >= end_pfn) | |
605 | return; | |
606 | ||
607 | if (!list_empty(&nosave_regions)) { | |
608 | /* Try to extend the previous region (they should be sorted) */ | |
609 | region = list_entry(nosave_regions.prev, | |
610 | struct nosave_region, list); | |
611 | if (region->end_pfn == start_pfn) { | |
612 | region->end_pfn = end_pfn; | |
613 | goto Report; | |
614 | } | |
615 | } | |
940d67f6 JB |
616 | if (use_kmalloc) { |
617 | /* during init, this shouldn't fail */ | |
618 | region = kmalloc(sizeof(struct nosave_region), GFP_KERNEL); | |
619 | BUG_ON(!region); | |
620 | } else | |
621 | /* This allocation cannot fail */ | |
622 | region = alloc_bootmem_low(sizeof(struct nosave_region)); | |
74dfd666 RW |
623 | region->start_pfn = start_pfn; |
624 | region->end_pfn = end_pfn; | |
625 | list_add_tail(®ion->list, &nosave_regions); | |
626 | Report: | |
23976728 | 627 | printk(KERN_INFO "PM: Registered nosave memory: %016lx - %016lx\n", |
74dfd666 RW |
628 | start_pfn << PAGE_SHIFT, end_pfn << PAGE_SHIFT); |
629 | } | |
630 | ||
631 | /* | |
632 | * Set bits in this map correspond to the page frames the contents of which | |
633 | * should not be saved during the suspend. | |
634 | */ | |
635 | static struct memory_bitmap *forbidden_pages_map; | |
636 | ||
637 | /* Set bits in this map correspond to free page frames. */ | |
638 | static struct memory_bitmap *free_pages_map; | |
639 | ||
640 | /* | |
641 | * Each page frame allocated for creating the image is marked by setting the | |
642 | * corresponding bits in forbidden_pages_map and free_pages_map simultaneously | |
643 | */ | |
644 | ||
645 | void swsusp_set_page_free(struct page *page) | |
646 | { | |
647 | if (free_pages_map) | |
648 | memory_bm_set_bit(free_pages_map, page_to_pfn(page)); | |
649 | } | |
650 | ||
651 | static int swsusp_page_is_free(struct page *page) | |
652 | { | |
653 | return free_pages_map ? | |
654 | memory_bm_test_bit(free_pages_map, page_to_pfn(page)) : 0; | |
655 | } | |
656 | ||
657 | void swsusp_unset_page_free(struct page *page) | |
658 | { | |
659 | if (free_pages_map) | |
660 | memory_bm_clear_bit(free_pages_map, page_to_pfn(page)); | |
661 | } | |
662 | ||
663 | static void swsusp_set_page_forbidden(struct page *page) | |
664 | { | |
665 | if (forbidden_pages_map) | |
666 | memory_bm_set_bit(forbidden_pages_map, page_to_pfn(page)); | |
667 | } | |
668 | ||
669 | int swsusp_page_is_forbidden(struct page *page) | |
670 | { | |
671 | return forbidden_pages_map ? | |
672 | memory_bm_test_bit(forbidden_pages_map, page_to_pfn(page)) : 0; | |
673 | } | |
674 | ||
675 | static void swsusp_unset_page_forbidden(struct page *page) | |
676 | { | |
677 | if (forbidden_pages_map) | |
678 | memory_bm_clear_bit(forbidden_pages_map, page_to_pfn(page)); | |
679 | } | |
680 | ||
681 | /** | |
682 | * mark_nosave_pages - set bits corresponding to the page frames the | |
683 | * contents of which should not be saved in a given bitmap. | |
684 | */ | |
685 | ||
686 | static void mark_nosave_pages(struct memory_bitmap *bm) | |
687 | { | |
688 | struct nosave_region *region; | |
689 | ||
690 | if (list_empty(&nosave_regions)) | |
691 | return; | |
692 | ||
693 | list_for_each_entry(region, &nosave_regions, list) { | |
694 | unsigned long pfn; | |
695 | ||
23976728 | 696 | pr_debug("PM: Marking nosave pages: %016lx - %016lx\n", |
74dfd666 RW |
697 | region->start_pfn << PAGE_SHIFT, |
698 | region->end_pfn << PAGE_SHIFT); | |
699 | ||
700 | for (pfn = region->start_pfn; pfn < region->end_pfn; pfn++) | |
a82f7119 RW |
701 | if (pfn_valid(pfn)) { |
702 | /* | |
703 | * It is safe to ignore the result of | |
704 | * mem_bm_set_bit_check() here, since we won't | |
705 | * touch the PFNs for which the error is | |
706 | * returned anyway. | |
707 | */ | |
708 | mem_bm_set_bit_check(bm, pfn); | |
709 | } | |
74dfd666 RW |
710 | } |
711 | } | |
712 | ||
713 | /** | |
714 | * create_basic_memory_bitmaps - create bitmaps needed for marking page | |
715 | * frames that should not be saved and free page frames. The pointers | |
716 | * forbidden_pages_map and free_pages_map are only modified if everything | |
717 | * goes well, because we don't want the bits to be used before both bitmaps | |
718 | * are set up. | |
719 | */ | |
720 | ||
721 | int create_basic_memory_bitmaps(void) | |
722 | { | |
723 | struct memory_bitmap *bm1, *bm2; | |
724 | int error = 0; | |
725 | ||
726 | BUG_ON(forbidden_pages_map || free_pages_map); | |
727 | ||
0709db60 | 728 | bm1 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL); |
74dfd666 RW |
729 | if (!bm1) |
730 | return -ENOMEM; | |
731 | ||
0709db60 | 732 | error = memory_bm_create(bm1, GFP_KERNEL, PG_ANY); |
74dfd666 RW |
733 | if (error) |
734 | goto Free_first_object; | |
735 | ||
0709db60 | 736 | bm2 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL); |
74dfd666 RW |
737 | if (!bm2) |
738 | goto Free_first_bitmap; | |
739 | ||
0709db60 | 740 | error = memory_bm_create(bm2, GFP_KERNEL, PG_ANY); |
74dfd666 RW |
741 | if (error) |
742 | goto Free_second_object; | |
743 | ||
744 | forbidden_pages_map = bm1; | |
745 | free_pages_map = bm2; | |
746 | mark_nosave_pages(forbidden_pages_map); | |
747 | ||
23976728 | 748 | pr_debug("PM: Basic memory bitmaps created\n"); |
74dfd666 RW |
749 | |
750 | return 0; | |
751 | ||
752 | Free_second_object: | |
753 | kfree(bm2); | |
754 | Free_first_bitmap: | |
755 | memory_bm_free(bm1, PG_UNSAFE_CLEAR); | |
756 | Free_first_object: | |
757 | kfree(bm1); | |
758 | return -ENOMEM; | |
759 | } | |
760 | ||
761 | /** | |
762 | * free_basic_memory_bitmaps - free memory bitmaps allocated by | |
763 | * create_basic_memory_bitmaps(). The auxiliary pointers are necessary | |
764 | * so that the bitmaps themselves are not referred to while they are being | |
765 | * freed. | |
766 | */ | |
767 | ||
768 | void free_basic_memory_bitmaps(void) | |
769 | { | |
770 | struct memory_bitmap *bm1, *bm2; | |
771 | ||
772 | BUG_ON(!(forbidden_pages_map && free_pages_map)); | |
773 | ||
774 | bm1 = forbidden_pages_map; | |
775 | bm2 = free_pages_map; | |
776 | forbidden_pages_map = NULL; | |
777 | free_pages_map = NULL; | |
778 | memory_bm_free(bm1, PG_UNSAFE_CLEAR); | |
779 | kfree(bm1); | |
780 | memory_bm_free(bm2, PG_UNSAFE_CLEAR); | |
781 | kfree(bm2); | |
782 | ||
23976728 | 783 | pr_debug("PM: Basic memory bitmaps freed\n"); |
74dfd666 RW |
784 | } |
785 | ||
b788db79 RW |
786 | /** |
787 | * snapshot_additional_pages - estimate the number of additional pages | |
788 | * be needed for setting up the suspend image data structures for given | |
789 | * zone (usually the returned value is greater than the exact number) | |
790 | */ | |
791 | ||
792 | unsigned int snapshot_additional_pages(struct zone *zone) | |
793 | { | |
794 | unsigned int res; | |
795 | ||
796 | res = DIV_ROUND_UP(zone->spanned_pages, BM_BITS_PER_BLOCK); | |
797 | res += DIV_ROUND_UP(res * sizeof(struct bm_block), PAGE_SIZE); | |
8357376d | 798 | return 2 * res; |
b788db79 RW |
799 | } |
800 | ||
8357376d RW |
801 | #ifdef CONFIG_HIGHMEM |
802 | /** | |
803 | * count_free_highmem_pages - compute the total number of free highmem | |
804 | * pages, system-wide. | |
805 | */ | |
806 | ||
807 | static unsigned int count_free_highmem_pages(void) | |
808 | { | |
809 | struct zone *zone; | |
810 | unsigned int cnt = 0; | |
811 | ||
ee99c71c KM |
812 | for_each_populated_zone(zone) |
813 | if (is_highmem(zone)) | |
d23ad423 | 814 | cnt += zone_page_state(zone, NR_FREE_PAGES); |
8357376d RW |
815 | |
816 | return cnt; | |
817 | } | |
818 | ||
819 | /** | |
820 | * saveable_highmem_page - Determine whether a highmem page should be | |
821 | * included in the suspend image. | |
822 | * | |
823 | * We should save the page if it isn't Nosave or NosaveFree, or Reserved, | |
824 | * and it isn't a part of a free chunk of pages. | |
825 | */ | |
846705de | 826 | static struct page *saveable_highmem_page(struct zone *zone, unsigned long pfn) |
8357376d RW |
827 | { |
828 | struct page *page; | |
829 | ||
830 | if (!pfn_valid(pfn)) | |
831 | return NULL; | |
832 | ||
833 | page = pfn_to_page(pfn); | |
846705de RW |
834 | if (page_zone(page) != zone) |
835 | return NULL; | |
8357376d RW |
836 | |
837 | BUG_ON(!PageHighMem(page)); | |
838 | ||
7be98234 RW |
839 | if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page) || |
840 | PageReserved(page)) | |
8357376d RW |
841 | return NULL; |
842 | ||
843 | return page; | |
844 | } | |
845 | ||
846 | /** | |
847 | * count_highmem_pages - compute the total number of saveable highmem | |
848 | * pages. | |
849 | */ | |
850 | ||
fe419535 | 851 | static unsigned int count_highmem_pages(void) |
8357376d RW |
852 | { |
853 | struct zone *zone; | |
854 | unsigned int n = 0; | |
855 | ||
856 | for_each_zone(zone) { | |
857 | unsigned long pfn, max_zone_pfn; | |
858 | ||
859 | if (!is_highmem(zone)) | |
860 | continue; | |
861 | ||
862 | mark_free_pages(zone); | |
863 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; | |
864 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
846705de | 865 | if (saveable_highmem_page(zone, pfn)) |
8357376d RW |
866 | n++; |
867 | } | |
868 | return n; | |
869 | } | |
870 | #else | |
846705de RW |
871 | static inline void *saveable_highmem_page(struct zone *z, unsigned long p) |
872 | { | |
873 | return NULL; | |
874 | } | |
8357376d RW |
875 | #endif /* CONFIG_HIGHMEM */ |
876 | ||
25761b6e | 877 | /** |
8a235efa RW |
878 | * saveable_page - Determine whether a non-highmem page should be included |
879 | * in the suspend image. | |
25761b6e | 880 | * |
8357376d RW |
881 | * We should save the page if it isn't Nosave, and is not in the range |
882 | * of pages statically defined as 'unsaveable', and it isn't a part of | |
883 | * a free chunk of pages. | |
25761b6e | 884 | */ |
846705de | 885 | static struct page *saveable_page(struct zone *zone, unsigned long pfn) |
25761b6e | 886 | { |
de491861 | 887 | struct page *page; |
25761b6e RW |
888 | |
889 | if (!pfn_valid(pfn)) | |
ae83c5ee | 890 | return NULL; |
25761b6e RW |
891 | |
892 | page = pfn_to_page(pfn); | |
846705de RW |
893 | if (page_zone(page) != zone) |
894 | return NULL; | |
ae83c5ee | 895 | |
8357376d RW |
896 | BUG_ON(PageHighMem(page)); |
897 | ||
7be98234 | 898 | if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page)) |
ae83c5ee | 899 | return NULL; |
8357376d | 900 | |
8a235efa RW |
901 | if (PageReserved(page) |
902 | && (!kernel_page_present(page) || pfn_is_nosave(pfn))) | |
ae83c5ee | 903 | return NULL; |
25761b6e | 904 | |
ae83c5ee | 905 | return page; |
25761b6e RW |
906 | } |
907 | ||
8357376d RW |
908 | /** |
909 | * count_data_pages - compute the total number of saveable non-highmem | |
910 | * pages. | |
911 | */ | |
912 | ||
fe419535 | 913 | static unsigned int count_data_pages(void) |
25761b6e RW |
914 | { |
915 | struct zone *zone; | |
ae83c5ee | 916 | unsigned long pfn, max_zone_pfn; |
dc19d507 | 917 | unsigned int n = 0; |
25761b6e | 918 | |
8357376d | 919 | for_each_zone(zone) { |
25761b6e RW |
920 | if (is_highmem(zone)) |
921 | continue; | |
8357376d | 922 | |
25761b6e | 923 | mark_free_pages(zone); |
ae83c5ee RW |
924 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
925 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
846705de | 926 | if (saveable_page(zone, pfn)) |
8357376d | 927 | n++; |
25761b6e | 928 | } |
a0f49651 | 929 | return n; |
25761b6e RW |
930 | } |
931 | ||
8357376d RW |
932 | /* This is needed, because copy_page and memcpy are not usable for copying |
933 | * task structs. | |
934 | */ | |
935 | static inline void do_copy_page(long *dst, long *src) | |
f623f0db RW |
936 | { |
937 | int n; | |
938 | ||
f623f0db RW |
939 | for (n = PAGE_SIZE / sizeof(long); n; n--) |
940 | *dst++ = *src++; | |
941 | } | |
942 | ||
8a235efa RW |
943 | |
944 | /** | |
945 | * safe_copy_page - check if the page we are going to copy is marked as | |
946 | * present in the kernel page tables (this always is the case if | |
947 | * CONFIG_DEBUG_PAGEALLOC is not set and in that case | |
948 | * kernel_page_present() always returns 'true'). | |
949 | */ | |
950 | static void safe_copy_page(void *dst, struct page *s_page) | |
951 | { | |
952 | if (kernel_page_present(s_page)) { | |
953 | do_copy_page(dst, page_address(s_page)); | |
954 | } else { | |
955 | kernel_map_pages(s_page, 1, 1); | |
956 | do_copy_page(dst, page_address(s_page)); | |
957 | kernel_map_pages(s_page, 1, 0); | |
958 | } | |
959 | } | |
960 | ||
961 | ||
8357376d RW |
962 | #ifdef CONFIG_HIGHMEM |
963 | static inline struct page * | |
964 | page_is_saveable(struct zone *zone, unsigned long pfn) | |
965 | { | |
966 | return is_highmem(zone) ? | |
846705de | 967 | saveable_highmem_page(zone, pfn) : saveable_page(zone, pfn); |
8357376d RW |
968 | } |
969 | ||
8a235efa | 970 | static void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) |
8357376d RW |
971 | { |
972 | struct page *s_page, *d_page; | |
973 | void *src, *dst; | |
974 | ||
975 | s_page = pfn_to_page(src_pfn); | |
976 | d_page = pfn_to_page(dst_pfn); | |
977 | if (PageHighMem(s_page)) { | |
978 | src = kmap_atomic(s_page, KM_USER0); | |
979 | dst = kmap_atomic(d_page, KM_USER1); | |
980 | do_copy_page(dst, src); | |
981 | kunmap_atomic(src, KM_USER0); | |
982 | kunmap_atomic(dst, KM_USER1); | |
983 | } else { | |
8357376d RW |
984 | if (PageHighMem(d_page)) { |
985 | /* Page pointed to by src may contain some kernel | |
986 | * data modified by kmap_atomic() | |
987 | */ | |
8a235efa | 988 | safe_copy_page(buffer, s_page); |
baa5835d | 989 | dst = kmap_atomic(d_page, KM_USER0); |
8357376d RW |
990 | memcpy(dst, buffer, PAGE_SIZE); |
991 | kunmap_atomic(dst, KM_USER0); | |
992 | } else { | |
8a235efa | 993 | safe_copy_page(page_address(d_page), s_page); |
8357376d RW |
994 | } |
995 | } | |
996 | } | |
997 | #else | |
846705de | 998 | #define page_is_saveable(zone, pfn) saveable_page(zone, pfn) |
8357376d | 999 | |
8a235efa | 1000 | static inline void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) |
8357376d | 1001 | { |
8a235efa RW |
1002 | safe_copy_page(page_address(pfn_to_page(dst_pfn)), |
1003 | pfn_to_page(src_pfn)); | |
8357376d RW |
1004 | } |
1005 | #endif /* CONFIG_HIGHMEM */ | |
1006 | ||
b788db79 RW |
1007 | static void |
1008 | copy_data_pages(struct memory_bitmap *copy_bm, struct memory_bitmap *orig_bm) | |
25761b6e RW |
1009 | { |
1010 | struct zone *zone; | |
b788db79 | 1011 | unsigned long pfn; |
25761b6e | 1012 | |
8357376d | 1013 | for_each_zone(zone) { |
b788db79 RW |
1014 | unsigned long max_zone_pfn; |
1015 | ||
25761b6e | 1016 | mark_free_pages(zone); |
ae83c5ee | 1017 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
b788db79 | 1018 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) |
8357376d | 1019 | if (page_is_saveable(zone, pfn)) |
b788db79 | 1020 | memory_bm_set_bit(orig_bm, pfn); |
25761b6e | 1021 | } |
b788db79 RW |
1022 | memory_bm_position_reset(orig_bm); |
1023 | memory_bm_position_reset(copy_bm); | |
df7c4872 | 1024 | for(;;) { |
b788db79 | 1025 | pfn = memory_bm_next_pfn(orig_bm); |
df7c4872 FW |
1026 | if (unlikely(pfn == BM_END_OF_MAP)) |
1027 | break; | |
1028 | copy_data_page(memory_bm_next_pfn(copy_bm), pfn); | |
1029 | } | |
25761b6e RW |
1030 | } |
1031 | ||
8357376d RW |
1032 | /* Total number of image pages */ |
1033 | static unsigned int nr_copy_pages; | |
1034 | /* Number of pages needed for saving the original pfns of the image pages */ | |
1035 | static unsigned int nr_meta_pages; | |
64a473cb RW |
1036 | /* |
1037 | * Numbers of normal and highmem page frames allocated for hibernation image | |
1038 | * before suspending devices. | |
1039 | */ | |
1040 | unsigned int alloc_normal, alloc_highmem; | |
1041 | /* | |
1042 | * Memory bitmap used for marking saveable pages (during hibernation) or | |
1043 | * hibernation image pages (during restore) | |
1044 | */ | |
1045 | static struct memory_bitmap orig_bm; | |
1046 | /* | |
1047 | * Memory bitmap used during hibernation for marking allocated page frames that | |
1048 | * will contain copies of saveable pages. During restore it is initially used | |
1049 | * for marking hibernation image pages, but then the set bits from it are | |
1050 | * duplicated in @orig_bm and it is released. On highmem systems it is next | |
1051 | * used for marking "safe" highmem pages, but it has to be reinitialized for | |
1052 | * this purpose. | |
1053 | */ | |
1054 | static struct memory_bitmap copy_bm; | |
8357376d | 1055 | |
25761b6e | 1056 | /** |
940864dd | 1057 | * swsusp_free - free pages allocated for the suspend. |
cd560bb2 | 1058 | * |
940864dd RW |
1059 | * Suspend pages are alocated before the atomic copy is made, so we |
1060 | * need to release them after the resume. | |
25761b6e RW |
1061 | */ |
1062 | ||
1063 | void swsusp_free(void) | |
1064 | { | |
1065 | struct zone *zone; | |
ae83c5ee | 1066 | unsigned long pfn, max_zone_pfn; |
25761b6e RW |
1067 | |
1068 | for_each_zone(zone) { | |
ae83c5ee RW |
1069 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
1070 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
1071 | if (pfn_valid(pfn)) { | |
1072 | struct page *page = pfn_to_page(pfn); | |
1073 | ||
7be98234 RW |
1074 | if (swsusp_page_is_forbidden(page) && |
1075 | swsusp_page_is_free(page)) { | |
1076 | swsusp_unset_page_forbidden(page); | |
1077 | swsusp_unset_page_free(page); | |
8357376d | 1078 | __free_page(page); |
25761b6e RW |
1079 | } |
1080 | } | |
1081 | } | |
f577eb30 RW |
1082 | nr_copy_pages = 0; |
1083 | nr_meta_pages = 0; | |
75534b50 | 1084 | restore_pblist = NULL; |
6e1819d6 | 1085 | buffer = NULL; |
64a473cb RW |
1086 | alloc_normal = 0; |
1087 | alloc_highmem = 0; | |
25761b6e RW |
1088 | } |
1089 | ||
4bb33435 RW |
1090 | /* Helper functions used for the shrinking of memory. */ |
1091 | ||
1092 | #define GFP_IMAGE (GFP_KERNEL | __GFP_NOWARN) | |
1093 | ||
fe419535 | 1094 | /** |
4bb33435 RW |
1095 | * preallocate_image_pages - Allocate a number of pages for hibernation image |
1096 | * @nr_pages: Number of page frames to allocate. | |
1097 | * @mask: GFP flags to use for the allocation. | |
fe419535 | 1098 | * |
4bb33435 RW |
1099 | * Return value: Number of page frames actually allocated |
1100 | */ | |
1101 | static unsigned long preallocate_image_pages(unsigned long nr_pages, gfp_t mask) | |
1102 | { | |
1103 | unsigned long nr_alloc = 0; | |
1104 | ||
1105 | while (nr_pages > 0) { | |
64a473cb RW |
1106 | struct page *page; |
1107 | ||
1108 | page = alloc_image_page(mask); | |
1109 | if (!page) | |
4bb33435 | 1110 | break; |
64a473cb RW |
1111 | memory_bm_set_bit(©_bm, page_to_pfn(page)); |
1112 | if (PageHighMem(page)) | |
1113 | alloc_highmem++; | |
1114 | else | |
1115 | alloc_normal++; | |
4bb33435 RW |
1116 | nr_pages--; |
1117 | nr_alloc++; | |
1118 | } | |
1119 | ||
1120 | return nr_alloc; | |
1121 | } | |
1122 | ||
1123 | static unsigned long preallocate_image_memory(unsigned long nr_pages) | |
1124 | { | |
1125 | return preallocate_image_pages(nr_pages, GFP_IMAGE); | |
1126 | } | |
1127 | ||
1128 | #ifdef CONFIG_HIGHMEM | |
1129 | static unsigned long preallocate_image_highmem(unsigned long nr_pages) | |
1130 | { | |
1131 | return preallocate_image_pages(nr_pages, GFP_IMAGE | __GFP_HIGHMEM); | |
1132 | } | |
1133 | ||
1134 | /** | |
1135 | * __fraction - Compute (an approximation of) x * (multiplier / base) | |
fe419535 | 1136 | */ |
4bb33435 RW |
1137 | static unsigned long __fraction(u64 x, u64 multiplier, u64 base) |
1138 | { | |
1139 | x *= multiplier; | |
1140 | do_div(x, base); | |
1141 | return (unsigned long)x; | |
1142 | } | |
fe419535 | 1143 | |
4bb33435 RW |
1144 | static unsigned long preallocate_highmem_fraction(unsigned long nr_pages, |
1145 | unsigned long highmem, | |
1146 | unsigned long total) | |
fe419535 | 1147 | { |
4bb33435 RW |
1148 | unsigned long alloc = __fraction(nr_pages, highmem, total); |
1149 | ||
1150 | return preallocate_image_pages(alloc, GFP_IMAGE | __GFP_HIGHMEM); | |
fe419535 | 1151 | } |
4bb33435 RW |
1152 | #else /* CONFIG_HIGHMEM */ |
1153 | static inline unsigned long preallocate_image_highmem(unsigned long nr_pages) | |
1154 | { | |
1155 | return 0; | |
1156 | } | |
1157 | ||
1158 | static inline unsigned long preallocate_highmem_fraction(unsigned long nr_pages, | |
1159 | unsigned long highmem, | |
1160 | unsigned long total) | |
1161 | { | |
1162 | return 0; | |
1163 | } | |
1164 | #endif /* CONFIG_HIGHMEM */ | |
fe419535 | 1165 | |
4bb33435 | 1166 | /** |
64a473cb RW |
1167 | * free_unnecessary_pages - Release preallocated pages not needed for the image |
1168 | */ | |
1169 | static void free_unnecessary_pages(void) | |
1170 | { | |
1171 | unsigned long save_highmem, to_free_normal, to_free_highmem; | |
1172 | ||
1173 | to_free_normal = alloc_normal - count_data_pages(); | |
1174 | save_highmem = count_highmem_pages(); | |
1175 | if (alloc_highmem > save_highmem) { | |
1176 | to_free_highmem = alloc_highmem - save_highmem; | |
1177 | } else { | |
1178 | to_free_highmem = 0; | |
1179 | to_free_normal -= save_highmem - alloc_highmem; | |
1180 | } | |
1181 | ||
1182 | memory_bm_position_reset(©_bm); | |
1183 | ||
1184 | while (to_free_normal > 0 && to_free_highmem > 0) { | |
1185 | unsigned long pfn = memory_bm_next_pfn(©_bm); | |
1186 | struct page *page = pfn_to_page(pfn); | |
1187 | ||
1188 | if (PageHighMem(page)) { | |
1189 | if (!to_free_highmem) | |
1190 | continue; | |
1191 | to_free_highmem--; | |
1192 | alloc_highmem--; | |
1193 | } else { | |
1194 | if (!to_free_normal) | |
1195 | continue; | |
1196 | to_free_normal--; | |
1197 | alloc_normal--; | |
1198 | } | |
1199 | memory_bm_clear_bit(©_bm, pfn); | |
1200 | swsusp_unset_page_forbidden(page); | |
1201 | swsusp_unset_page_free(page); | |
1202 | __free_page(page); | |
1203 | } | |
1204 | } | |
1205 | ||
1206 | /** | |
1207 | * hibernate_preallocate_memory - Preallocate memory for hibernation image | |
4bb33435 RW |
1208 | * |
1209 | * To create a hibernation image it is necessary to make a copy of every page | |
1210 | * frame in use. We also need a number of page frames to be free during | |
1211 | * hibernation for allocations made while saving the image and for device | |
1212 | * drivers, in case they need to allocate memory from their hibernation | |
1213 | * callbacks (these two numbers are given by PAGES_FOR_IO and SPARE_PAGES, | |
1214 | * respectively, both of which are rough estimates). To make this happen, we | |
1215 | * compute the total number of available page frames and allocate at least | |
1216 | * | |
1217 | * ([page frames total] + PAGES_FOR_IO + [metadata pages]) / 2 + 2 * SPARE_PAGES | |
1218 | * | |
1219 | * of them, which corresponds to the maximum size of a hibernation image. | |
1220 | * | |
1221 | * If image_size is set below the number following from the above formula, | |
1222 | * the preallocation of memory is continued until the total number of saveable | |
1223 | * pages in the system is below the requested image size or it is impossible to | |
1224 | * allocate more memory, whichever happens first. | |
1225 | */ | |
64a473cb | 1226 | int hibernate_preallocate_memory(void) |
fe419535 | 1227 | { |
fe419535 | 1228 | struct zone *zone; |
4bb33435 | 1229 | unsigned long saveable, size, max_size, count, highmem, pages = 0; |
64a473cb | 1230 | unsigned long alloc, save_highmem, pages_highmem; |
fe419535 | 1231 | struct timeval start, stop; |
64a473cb | 1232 | int error; |
fe419535 | 1233 | |
64a473cb | 1234 | printk(KERN_INFO "PM: Preallocating image memory... "); |
fe419535 | 1235 | do_gettimeofday(&start); |
fe419535 | 1236 | |
64a473cb RW |
1237 | error = memory_bm_create(&orig_bm, GFP_IMAGE, PG_ANY); |
1238 | if (error) | |
1239 | goto err_out; | |
1240 | ||
1241 | error = memory_bm_create(©_bm, GFP_IMAGE, PG_ANY); | |
1242 | if (error) | |
1243 | goto err_out; | |
1244 | ||
1245 | alloc_normal = 0; | |
1246 | alloc_highmem = 0; | |
1247 | ||
4bb33435 | 1248 | /* Count the number of saveable data pages. */ |
64a473cb | 1249 | save_highmem = count_highmem_pages(); |
4bb33435 | 1250 | saveable = count_data_pages(); |
fe419535 | 1251 | |
4bb33435 RW |
1252 | /* |
1253 | * Compute the total number of page frames we can use (count) and the | |
1254 | * number of pages needed for image metadata (size). | |
1255 | */ | |
1256 | count = saveable; | |
64a473cb RW |
1257 | saveable += save_highmem; |
1258 | highmem = save_highmem; | |
4bb33435 RW |
1259 | size = 0; |
1260 | for_each_populated_zone(zone) { | |
1261 | size += snapshot_additional_pages(zone); | |
1262 | if (is_highmem(zone)) | |
1263 | highmem += zone_page_state(zone, NR_FREE_PAGES); | |
1264 | else | |
1265 | count += zone_page_state(zone, NR_FREE_PAGES); | |
1266 | } | |
1267 | count += highmem; | |
1268 | count -= totalreserve_pages; | |
1269 | ||
1270 | /* Compute the maximum number of saveable pages to leave in memory. */ | |
1271 | max_size = (count - (size + PAGES_FOR_IO)) / 2 - 2 * SPARE_PAGES; | |
1272 | size = DIV_ROUND_UP(image_size, PAGE_SIZE); | |
1273 | if (size > max_size) | |
1274 | size = max_size; | |
1275 | /* | |
1276 | * If the maximum is not less than the current number of saveable pages | |
64a473cb | 1277 | * in memory, allocate page frames for the image and we're done. |
4bb33435 | 1278 | */ |
64a473cb RW |
1279 | if (size >= saveable) { |
1280 | pages = preallocate_image_highmem(save_highmem); | |
1281 | pages += preallocate_image_memory(saveable - pages); | |
4bb33435 | 1282 | goto out; |
64a473cb | 1283 | } |
4bb33435 RW |
1284 | |
1285 | /* | |
1286 | * Let the memory management subsystem know that we're going to need a | |
1287 | * large number of page frames to allocate and make it free some memory. | |
1288 | * NOTE: If this is not done, performance will be hurt badly in some | |
1289 | * test cases. | |
1290 | */ | |
1291 | shrink_all_memory(saveable - size); | |
1292 | ||
1293 | /* | |
1294 | * The number of saveable pages in memory was too high, so apply some | |
1295 | * pressure to decrease it. First, make room for the largest possible | |
1296 | * image and fail if that doesn't work. Next, try to decrease the size | |
1297 | * of the image as much as indicated by image_size using allocations | |
1298 | * from highmem and non-highmem zones separately. | |
1299 | */ | |
1300 | pages_highmem = preallocate_image_highmem(highmem / 2); | |
1301 | alloc = (count - max_size) - pages_highmem; | |
1302 | pages = preallocate_image_memory(alloc); | |
64a473cb RW |
1303 | if (pages < alloc) |
1304 | goto err_out; | |
4bb33435 RW |
1305 | size = max_size - size; |
1306 | alloc = size; | |
1307 | size = preallocate_highmem_fraction(size, highmem, count); | |
1308 | pages_highmem += size; | |
1309 | alloc -= size; | |
1310 | pages += preallocate_image_memory(alloc); | |
1311 | pages += pages_highmem; | |
1312 | ||
64a473cb RW |
1313 | /* |
1314 | * We only need as many page frames for the image as there are saveable | |
1315 | * pages in memory, but we have allocated more. Release the excessive | |
1316 | * ones now. | |
1317 | */ | |
1318 | free_unnecessary_pages(); | |
4bb33435 RW |
1319 | |
1320 | out: | |
fe419535 | 1321 | do_gettimeofday(&stop); |
64a473cb RW |
1322 | printk(KERN_CONT "done (allocated %lu pages)\n", pages); |
1323 | swsusp_show_speed(&start, &stop, pages, "Allocated"); | |
fe419535 RW |
1324 | |
1325 | return 0; | |
64a473cb RW |
1326 | |
1327 | err_out: | |
1328 | printk(KERN_CONT "\n"); | |
1329 | swsusp_free(); | |
1330 | return -ENOMEM; | |
fe419535 RW |
1331 | } |
1332 | ||
8357376d RW |
1333 | #ifdef CONFIG_HIGHMEM |
1334 | /** | |
1335 | * count_pages_for_highmem - compute the number of non-highmem pages | |
1336 | * that will be necessary for creating copies of highmem pages. | |
1337 | */ | |
1338 | ||
1339 | static unsigned int count_pages_for_highmem(unsigned int nr_highmem) | |
1340 | { | |
64a473cb | 1341 | unsigned int free_highmem = count_free_highmem_pages() + alloc_highmem; |
8357376d RW |
1342 | |
1343 | if (free_highmem >= nr_highmem) | |
1344 | nr_highmem = 0; | |
1345 | else | |
1346 | nr_highmem -= free_highmem; | |
1347 | ||
1348 | return nr_highmem; | |
1349 | } | |
1350 | #else | |
1351 | static unsigned int | |
1352 | count_pages_for_highmem(unsigned int nr_highmem) { return 0; } | |
1353 | #endif /* CONFIG_HIGHMEM */ | |
25761b6e RW |
1354 | |
1355 | /** | |
8357376d RW |
1356 | * enough_free_mem - Make sure we have enough free memory for the |
1357 | * snapshot image. | |
25761b6e RW |
1358 | */ |
1359 | ||
8357376d | 1360 | static int enough_free_mem(unsigned int nr_pages, unsigned int nr_highmem) |
25761b6e | 1361 | { |
e5e2fa78 | 1362 | struct zone *zone; |
64a473cb | 1363 | unsigned int free = alloc_normal; |
e5e2fa78 | 1364 | |
64a473cb | 1365 | for_each_zone(zone) |
8357376d | 1366 | if (!is_highmem(zone)) |
d23ad423 | 1367 | free += zone_page_state(zone, NR_FREE_PAGES); |
940864dd | 1368 | |
8357376d | 1369 | nr_pages += count_pages_for_highmem(nr_highmem); |
64a473cb RW |
1370 | pr_debug("PM: Normal pages needed: %u + %u, available pages: %u\n", |
1371 | nr_pages, PAGES_FOR_IO, free); | |
940864dd | 1372 | |
64a473cb | 1373 | return free > nr_pages + PAGES_FOR_IO; |
25761b6e RW |
1374 | } |
1375 | ||
8357376d RW |
1376 | #ifdef CONFIG_HIGHMEM |
1377 | /** | |
1378 | * get_highmem_buffer - if there are some highmem pages in the suspend | |
1379 | * image, we may need the buffer to copy them and/or load their data. | |
1380 | */ | |
1381 | ||
1382 | static inline int get_highmem_buffer(int safe_needed) | |
1383 | { | |
1384 | buffer = get_image_page(GFP_ATOMIC | __GFP_COLD, safe_needed); | |
1385 | return buffer ? 0 : -ENOMEM; | |
1386 | } | |
1387 | ||
1388 | /** | |
1389 | * alloc_highmem_image_pages - allocate some highmem pages for the image. | |
1390 | * Try to allocate as many pages as needed, but if the number of free | |
1391 | * highmem pages is lesser than that, allocate them all. | |
1392 | */ | |
1393 | ||
1394 | static inline unsigned int | |
64a473cb | 1395 | alloc_highmem_pages(struct memory_bitmap *bm, unsigned int nr_highmem) |
8357376d RW |
1396 | { |
1397 | unsigned int to_alloc = count_free_highmem_pages(); | |
1398 | ||
1399 | if (to_alloc > nr_highmem) | |
1400 | to_alloc = nr_highmem; | |
1401 | ||
1402 | nr_highmem -= to_alloc; | |
1403 | while (to_alloc-- > 0) { | |
1404 | struct page *page; | |
1405 | ||
1406 | page = alloc_image_page(__GFP_HIGHMEM); | |
1407 | memory_bm_set_bit(bm, page_to_pfn(page)); | |
1408 | } | |
1409 | return nr_highmem; | |
1410 | } | |
1411 | #else | |
1412 | static inline int get_highmem_buffer(int safe_needed) { return 0; } | |
1413 | ||
1414 | static inline unsigned int | |
64a473cb | 1415 | alloc_highmem_pages(struct memory_bitmap *bm, unsigned int n) { return 0; } |
8357376d RW |
1416 | #endif /* CONFIG_HIGHMEM */ |
1417 | ||
1418 | /** | |
1419 | * swsusp_alloc - allocate memory for the suspend image | |
1420 | * | |
1421 | * We first try to allocate as many highmem pages as there are | |
1422 | * saveable highmem pages in the system. If that fails, we allocate | |
1423 | * non-highmem pages for the copies of the remaining highmem ones. | |
1424 | * | |
1425 | * In this approach it is likely that the copies of highmem pages will | |
1426 | * also be located in the high memory, because of the way in which | |
1427 | * copy_data_pages() works. | |
1428 | */ | |
1429 | ||
b788db79 RW |
1430 | static int |
1431 | swsusp_alloc(struct memory_bitmap *orig_bm, struct memory_bitmap *copy_bm, | |
8357376d | 1432 | unsigned int nr_pages, unsigned int nr_highmem) |
054bd4c1 | 1433 | { |
64a473cb | 1434 | int error = 0; |
25761b6e | 1435 | |
8357376d RW |
1436 | if (nr_highmem > 0) { |
1437 | error = get_highmem_buffer(PG_ANY); | |
1438 | if (error) | |
64a473cb RW |
1439 | goto err_out; |
1440 | if (nr_highmem > alloc_highmem) { | |
1441 | nr_highmem -= alloc_highmem; | |
1442 | nr_pages += alloc_highmem_pages(copy_bm, nr_highmem); | |
1443 | } | |
8357376d | 1444 | } |
64a473cb RW |
1445 | if (nr_pages > alloc_normal) { |
1446 | nr_pages -= alloc_normal; | |
1447 | while (nr_pages-- > 0) { | |
1448 | struct page *page; | |
1449 | ||
1450 | page = alloc_image_page(GFP_ATOMIC | __GFP_COLD); | |
1451 | if (!page) | |
1452 | goto err_out; | |
1453 | memory_bm_set_bit(copy_bm, page_to_pfn(page)); | |
1454 | } | |
25761b6e | 1455 | } |
64a473cb | 1456 | |
b788db79 | 1457 | return 0; |
25761b6e | 1458 | |
64a473cb | 1459 | err_out: |
b788db79 | 1460 | swsusp_free(); |
64a473cb | 1461 | return error; |
25761b6e RW |
1462 | } |
1463 | ||
2e32a43e | 1464 | asmlinkage int swsusp_save(void) |
25761b6e | 1465 | { |
8357376d | 1466 | unsigned int nr_pages, nr_highmem; |
25761b6e | 1467 | |
23976728 | 1468 | printk(KERN_INFO "PM: Creating hibernation image: \n"); |
25761b6e | 1469 | |
9f8f2172 | 1470 | drain_local_pages(NULL); |
a0f49651 | 1471 | nr_pages = count_data_pages(); |
8357376d | 1472 | nr_highmem = count_highmem_pages(); |
23976728 | 1473 | printk(KERN_INFO "PM: Need to copy %u pages\n", nr_pages + nr_highmem); |
25761b6e | 1474 | |
8357376d | 1475 | if (!enough_free_mem(nr_pages, nr_highmem)) { |
23976728 | 1476 | printk(KERN_ERR "PM: Not enough free memory\n"); |
25761b6e RW |
1477 | return -ENOMEM; |
1478 | } | |
1479 | ||
8357376d | 1480 | if (swsusp_alloc(&orig_bm, ©_bm, nr_pages, nr_highmem)) { |
23976728 | 1481 | printk(KERN_ERR "PM: Memory allocation failed\n"); |
a0f49651 | 1482 | return -ENOMEM; |
8357376d | 1483 | } |
25761b6e RW |
1484 | |
1485 | /* During allocating of suspend pagedir, new cold pages may appear. | |
1486 | * Kill them. | |
1487 | */ | |
9f8f2172 | 1488 | drain_local_pages(NULL); |
b788db79 | 1489 | copy_data_pages(©_bm, &orig_bm); |
25761b6e RW |
1490 | |
1491 | /* | |
1492 | * End of critical section. From now on, we can write to memory, | |
1493 | * but we should not touch disk. This specially means we must _not_ | |
1494 | * touch swap space! Except we must write out our image of course. | |
1495 | */ | |
1496 | ||
8357376d | 1497 | nr_pages += nr_highmem; |
a0f49651 | 1498 | nr_copy_pages = nr_pages; |
8357376d | 1499 | nr_meta_pages = DIV_ROUND_UP(nr_pages * sizeof(long), PAGE_SIZE); |
a0f49651 | 1500 | |
23976728 RW |
1501 | printk(KERN_INFO "PM: Hibernation image created (%d pages copied)\n", |
1502 | nr_pages); | |
8357376d | 1503 | |
25761b6e RW |
1504 | return 0; |
1505 | } | |
f577eb30 | 1506 | |
d307c4a8 RW |
1507 | #ifndef CONFIG_ARCH_HIBERNATION_HEADER |
1508 | static int init_header_complete(struct swsusp_info *info) | |
f577eb30 | 1509 | { |
d307c4a8 | 1510 | memcpy(&info->uts, init_utsname(), sizeof(struct new_utsname)); |
f577eb30 | 1511 | info->version_code = LINUX_VERSION_CODE; |
d307c4a8 RW |
1512 | return 0; |
1513 | } | |
1514 | ||
1515 | static char *check_image_kernel(struct swsusp_info *info) | |
1516 | { | |
1517 | if (info->version_code != LINUX_VERSION_CODE) | |
1518 | return "kernel version"; | |
1519 | if (strcmp(info->uts.sysname,init_utsname()->sysname)) | |
1520 | return "system type"; | |
1521 | if (strcmp(info->uts.release,init_utsname()->release)) | |
1522 | return "kernel release"; | |
1523 | if (strcmp(info->uts.version,init_utsname()->version)) | |
1524 | return "version"; | |
1525 | if (strcmp(info->uts.machine,init_utsname()->machine)) | |
1526 | return "machine"; | |
1527 | return NULL; | |
1528 | } | |
1529 | #endif /* CONFIG_ARCH_HIBERNATION_HEADER */ | |
1530 | ||
af508b34 RW |
1531 | unsigned long snapshot_get_image_size(void) |
1532 | { | |
1533 | return nr_copy_pages + nr_meta_pages + 1; | |
1534 | } | |
1535 | ||
d307c4a8 RW |
1536 | static int init_header(struct swsusp_info *info) |
1537 | { | |
1538 | memset(info, 0, sizeof(struct swsusp_info)); | |
f577eb30 | 1539 | info->num_physpages = num_physpages; |
f577eb30 | 1540 | info->image_pages = nr_copy_pages; |
af508b34 | 1541 | info->pages = snapshot_get_image_size(); |
6e1819d6 RW |
1542 | info->size = info->pages; |
1543 | info->size <<= PAGE_SHIFT; | |
d307c4a8 | 1544 | return init_header_complete(info); |
f577eb30 RW |
1545 | } |
1546 | ||
1547 | /** | |
940864dd RW |
1548 | * pack_pfns - pfns corresponding to the set bits found in the bitmap @bm |
1549 | * are stored in the array @buf[] (1 page at a time) | |
f577eb30 RW |
1550 | */ |
1551 | ||
b788db79 | 1552 | static inline void |
940864dd | 1553 | pack_pfns(unsigned long *buf, struct memory_bitmap *bm) |
f577eb30 RW |
1554 | { |
1555 | int j; | |
1556 | ||
b788db79 | 1557 | for (j = 0; j < PAGE_SIZE / sizeof(long); j++) { |
940864dd RW |
1558 | buf[j] = memory_bm_next_pfn(bm); |
1559 | if (unlikely(buf[j] == BM_END_OF_MAP)) | |
b788db79 | 1560 | break; |
f577eb30 | 1561 | } |
f577eb30 RW |
1562 | } |
1563 | ||
1564 | /** | |
1565 | * snapshot_read_next - used for reading the system memory snapshot. | |
1566 | * | |
1567 | * On the first call to it @handle should point to a zeroed | |
1568 | * snapshot_handle structure. The structure gets updated and a pointer | |
1569 | * to it should be passed to this function every next time. | |
1570 | * | |
1571 | * The @count parameter should contain the number of bytes the caller | |
1572 | * wants to read from the snapshot. It must not be zero. | |
1573 | * | |
1574 | * On success the function returns a positive number. Then, the caller | |
1575 | * is allowed to read up to the returned number of bytes from the memory | |
1576 | * location computed by the data_of() macro. The number returned | |
1577 | * may be smaller than @count, but this only happens if the read would | |
1578 | * cross a page boundary otherwise. | |
1579 | * | |
1580 | * The function returns 0 to indicate the end of data stream condition, | |
1581 | * and a negative number is returned on error. In such cases the | |
1582 | * structure pointed to by @handle is not updated and should not be used | |
1583 | * any more. | |
1584 | */ | |
1585 | ||
1586 | int snapshot_read_next(struct snapshot_handle *handle, size_t count) | |
1587 | { | |
fb13a28b | 1588 | if (handle->cur > nr_meta_pages + nr_copy_pages) |
f577eb30 | 1589 | return 0; |
b788db79 | 1590 | |
f577eb30 RW |
1591 | if (!buffer) { |
1592 | /* This makes the buffer be freed by swsusp_free() */ | |
8357376d | 1593 | buffer = get_image_page(GFP_ATOMIC, PG_ANY); |
f577eb30 RW |
1594 | if (!buffer) |
1595 | return -ENOMEM; | |
1596 | } | |
1597 | if (!handle->offset) { | |
d307c4a8 RW |
1598 | int error; |
1599 | ||
1600 | error = init_header((struct swsusp_info *)buffer); | |
1601 | if (error) | |
1602 | return error; | |
f577eb30 | 1603 | handle->buffer = buffer; |
b788db79 RW |
1604 | memory_bm_position_reset(&orig_bm); |
1605 | memory_bm_position_reset(©_bm); | |
f577eb30 | 1606 | } |
fb13a28b RW |
1607 | if (handle->prev < handle->cur) { |
1608 | if (handle->cur <= nr_meta_pages) { | |
b788db79 | 1609 | memset(buffer, 0, PAGE_SIZE); |
940864dd | 1610 | pack_pfns(buffer, &orig_bm); |
f577eb30 | 1611 | } else { |
8357376d | 1612 | struct page *page; |
b788db79 | 1613 | |
8357376d RW |
1614 | page = pfn_to_page(memory_bm_next_pfn(©_bm)); |
1615 | if (PageHighMem(page)) { | |
1616 | /* Highmem pages are copied to the buffer, | |
1617 | * because we can't return with a kmapped | |
1618 | * highmem page (we may not be called again). | |
1619 | */ | |
1620 | void *kaddr; | |
1621 | ||
1622 | kaddr = kmap_atomic(page, KM_USER0); | |
1623 | memcpy(buffer, kaddr, PAGE_SIZE); | |
1624 | kunmap_atomic(kaddr, KM_USER0); | |
1625 | handle->buffer = buffer; | |
1626 | } else { | |
1627 | handle->buffer = page_address(page); | |
1628 | } | |
f577eb30 | 1629 | } |
fb13a28b | 1630 | handle->prev = handle->cur; |
f577eb30 | 1631 | } |
fb13a28b RW |
1632 | handle->buf_offset = handle->cur_offset; |
1633 | if (handle->cur_offset + count >= PAGE_SIZE) { | |
1634 | count = PAGE_SIZE - handle->cur_offset; | |
1635 | handle->cur_offset = 0; | |
1636 | handle->cur++; | |
f577eb30 | 1637 | } else { |
fb13a28b | 1638 | handle->cur_offset += count; |
f577eb30 RW |
1639 | } |
1640 | handle->offset += count; | |
1641 | return count; | |
1642 | } | |
1643 | ||
1644 | /** | |
1645 | * mark_unsafe_pages - mark the pages that cannot be used for storing | |
1646 | * the image during resume, because they conflict with the pages that | |
1647 | * had been used before suspend | |
1648 | */ | |
1649 | ||
940864dd | 1650 | static int mark_unsafe_pages(struct memory_bitmap *bm) |
f577eb30 RW |
1651 | { |
1652 | struct zone *zone; | |
ae83c5ee | 1653 | unsigned long pfn, max_zone_pfn; |
f577eb30 RW |
1654 | |
1655 | /* Clear page flags */ | |
8357376d | 1656 | for_each_zone(zone) { |
ae83c5ee RW |
1657 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
1658 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
1659 | if (pfn_valid(pfn)) | |
7be98234 | 1660 | swsusp_unset_page_free(pfn_to_page(pfn)); |
f577eb30 RW |
1661 | } |
1662 | ||
940864dd RW |
1663 | /* Mark pages that correspond to the "original" pfns as "unsafe" */ |
1664 | memory_bm_position_reset(bm); | |
1665 | do { | |
1666 | pfn = memory_bm_next_pfn(bm); | |
1667 | if (likely(pfn != BM_END_OF_MAP)) { | |
1668 | if (likely(pfn_valid(pfn))) | |
7be98234 | 1669 | swsusp_set_page_free(pfn_to_page(pfn)); |
940864dd RW |
1670 | else |
1671 | return -EFAULT; | |
1672 | } | |
1673 | } while (pfn != BM_END_OF_MAP); | |
f577eb30 | 1674 | |
940864dd | 1675 | allocated_unsafe_pages = 0; |
968808b8 | 1676 | |
f577eb30 RW |
1677 | return 0; |
1678 | } | |
1679 | ||
940864dd RW |
1680 | static void |
1681 | duplicate_memory_bitmap(struct memory_bitmap *dst, struct memory_bitmap *src) | |
f577eb30 | 1682 | { |
940864dd RW |
1683 | unsigned long pfn; |
1684 | ||
1685 | memory_bm_position_reset(src); | |
1686 | pfn = memory_bm_next_pfn(src); | |
1687 | while (pfn != BM_END_OF_MAP) { | |
1688 | memory_bm_set_bit(dst, pfn); | |
1689 | pfn = memory_bm_next_pfn(src); | |
f577eb30 RW |
1690 | } |
1691 | } | |
1692 | ||
d307c4a8 | 1693 | static int check_header(struct swsusp_info *info) |
f577eb30 | 1694 | { |
d307c4a8 | 1695 | char *reason; |
f577eb30 | 1696 | |
d307c4a8 RW |
1697 | reason = check_image_kernel(info); |
1698 | if (!reason && info->num_physpages != num_physpages) | |
f577eb30 | 1699 | reason = "memory size"; |
f577eb30 | 1700 | if (reason) { |
23976728 | 1701 | printk(KERN_ERR "PM: Image mismatch: %s\n", reason); |
f577eb30 RW |
1702 | return -EPERM; |
1703 | } | |
1704 | return 0; | |
1705 | } | |
1706 | ||
1707 | /** | |
1708 | * load header - check the image header and copy data from it | |
1709 | */ | |
1710 | ||
940864dd RW |
1711 | static int |
1712 | load_header(struct swsusp_info *info) | |
f577eb30 RW |
1713 | { |
1714 | int error; | |
f577eb30 | 1715 | |
940864dd | 1716 | restore_pblist = NULL; |
f577eb30 RW |
1717 | error = check_header(info); |
1718 | if (!error) { | |
f577eb30 RW |
1719 | nr_copy_pages = info->image_pages; |
1720 | nr_meta_pages = info->pages - info->image_pages - 1; | |
1721 | } | |
1722 | return error; | |
1723 | } | |
1724 | ||
1725 | /** | |
940864dd RW |
1726 | * unpack_orig_pfns - for each element of @buf[] (1 page at a time) set |
1727 | * the corresponding bit in the memory bitmap @bm | |
f577eb30 | 1728 | */ |
69643279 | 1729 | static int unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm) |
f577eb30 RW |
1730 | { |
1731 | int j; | |
1732 | ||
940864dd RW |
1733 | for (j = 0; j < PAGE_SIZE / sizeof(long); j++) { |
1734 | if (unlikely(buf[j] == BM_END_OF_MAP)) | |
1735 | break; | |
1736 | ||
69643279 RW |
1737 | if (memory_bm_pfn_present(bm, buf[j])) |
1738 | memory_bm_set_bit(bm, buf[j]); | |
1739 | else | |
1740 | return -EFAULT; | |
f577eb30 | 1741 | } |
69643279 RW |
1742 | |
1743 | return 0; | |
f577eb30 RW |
1744 | } |
1745 | ||
8357376d RW |
1746 | /* List of "safe" pages that may be used to store data loaded from the suspend |
1747 | * image | |
1748 | */ | |
1749 | static struct linked_page *safe_pages_list; | |
1750 | ||
1751 | #ifdef CONFIG_HIGHMEM | |
1752 | /* struct highmem_pbe is used for creating the list of highmem pages that | |
1753 | * should be restored atomically during the resume from disk, because the page | |
1754 | * frames they have occupied before the suspend are in use. | |
1755 | */ | |
1756 | struct highmem_pbe { | |
1757 | struct page *copy_page; /* data is here now */ | |
1758 | struct page *orig_page; /* data was here before the suspend */ | |
1759 | struct highmem_pbe *next; | |
1760 | }; | |
1761 | ||
1762 | /* List of highmem PBEs needed for restoring the highmem pages that were | |
1763 | * allocated before the suspend and included in the suspend image, but have | |
1764 | * also been allocated by the "resume" kernel, so their contents cannot be | |
1765 | * written directly to their "original" page frames. | |
1766 | */ | |
1767 | static struct highmem_pbe *highmem_pblist; | |
1768 | ||
1769 | /** | |
1770 | * count_highmem_image_pages - compute the number of highmem pages in the | |
1771 | * suspend image. The bits in the memory bitmap @bm that correspond to the | |
1772 | * image pages are assumed to be set. | |
1773 | */ | |
1774 | ||
1775 | static unsigned int count_highmem_image_pages(struct memory_bitmap *bm) | |
1776 | { | |
1777 | unsigned long pfn; | |
1778 | unsigned int cnt = 0; | |
1779 | ||
1780 | memory_bm_position_reset(bm); | |
1781 | pfn = memory_bm_next_pfn(bm); | |
1782 | while (pfn != BM_END_OF_MAP) { | |
1783 | if (PageHighMem(pfn_to_page(pfn))) | |
1784 | cnt++; | |
1785 | ||
1786 | pfn = memory_bm_next_pfn(bm); | |
1787 | } | |
1788 | return cnt; | |
1789 | } | |
1790 | ||
1791 | /** | |
1792 | * prepare_highmem_image - try to allocate as many highmem pages as | |
1793 | * there are highmem image pages (@nr_highmem_p points to the variable | |
1794 | * containing the number of highmem image pages). The pages that are | |
1795 | * "safe" (ie. will not be overwritten when the suspend image is | |
1796 | * restored) have the corresponding bits set in @bm (it must be | |
1797 | * unitialized). | |
1798 | * | |
1799 | * NOTE: This function should not be called if there are no highmem | |
1800 | * image pages. | |
1801 | */ | |
1802 | ||
1803 | static unsigned int safe_highmem_pages; | |
1804 | ||
1805 | static struct memory_bitmap *safe_highmem_bm; | |
1806 | ||
1807 | static int | |
1808 | prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p) | |
1809 | { | |
1810 | unsigned int to_alloc; | |
1811 | ||
1812 | if (memory_bm_create(bm, GFP_ATOMIC, PG_SAFE)) | |
1813 | return -ENOMEM; | |
1814 | ||
1815 | if (get_highmem_buffer(PG_SAFE)) | |
1816 | return -ENOMEM; | |
1817 | ||
1818 | to_alloc = count_free_highmem_pages(); | |
1819 | if (to_alloc > *nr_highmem_p) | |
1820 | to_alloc = *nr_highmem_p; | |
1821 | else | |
1822 | *nr_highmem_p = to_alloc; | |
1823 | ||
1824 | safe_highmem_pages = 0; | |
1825 | while (to_alloc-- > 0) { | |
1826 | struct page *page; | |
1827 | ||
1828 | page = alloc_page(__GFP_HIGHMEM); | |
7be98234 | 1829 | if (!swsusp_page_is_free(page)) { |
8357376d RW |
1830 | /* The page is "safe", set its bit the bitmap */ |
1831 | memory_bm_set_bit(bm, page_to_pfn(page)); | |
1832 | safe_highmem_pages++; | |
1833 | } | |
1834 | /* Mark the page as allocated */ | |
7be98234 RW |
1835 | swsusp_set_page_forbidden(page); |
1836 | swsusp_set_page_free(page); | |
8357376d RW |
1837 | } |
1838 | memory_bm_position_reset(bm); | |
1839 | safe_highmem_bm = bm; | |
1840 | return 0; | |
1841 | } | |
1842 | ||
1843 | /** | |
1844 | * get_highmem_page_buffer - for given highmem image page find the buffer | |
1845 | * that suspend_write_next() should set for its caller to write to. | |
1846 | * | |
1847 | * If the page is to be saved to its "original" page frame or a copy of | |
1848 | * the page is to be made in the highmem, @buffer is returned. Otherwise, | |
1849 | * the copy of the page is to be made in normal memory, so the address of | |
1850 | * the copy is returned. | |
1851 | * | |
1852 | * If @buffer is returned, the caller of suspend_write_next() will write | |
1853 | * the page's contents to @buffer, so they will have to be copied to the | |
1854 | * right location on the next call to suspend_write_next() and it is done | |
1855 | * with the help of copy_last_highmem_page(). For this purpose, if | |
1856 | * @buffer is returned, @last_highmem page is set to the page to which | |
1857 | * the data will have to be copied from @buffer. | |
1858 | */ | |
1859 | ||
1860 | static struct page *last_highmem_page; | |
1861 | ||
1862 | static void * | |
1863 | get_highmem_page_buffer(struct page *page, struct chain_allocator *ca) | |
1864 | { | |
1865 | struct highmem_pbe *pbe; | |
1866 | void *kaddr; | |
1867 | ||
7be98234 | 1868 | if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page)) { |
8357376d RW |
1869 | /* We have allocated the "original" page frame and we can |
1870 | * use it directly to store the loaded page. | |
1871 | */ | |
1872 | last_highmem_page = page; | |
1873 | return buffer; | |
1874 | } | |
1875 | /* The "original" page frame has not been allocated and we have to | |
1876 | * use a "safe" page frame to store the loaded page. | |
1877 | */ | |
1878 | pbe = chain_alloc(ca, sizeof(struct highmem_pbe)); | |
1879 | if (!pbe) { | |
1880 | swsusp_free(); | |
69643279 | 1881 | return ERR_PTR(-ENOMEM); |
8357376d RW |
1882 | } |
1883 | pbe->orig_page = page; | |
1884 | if (safe_highmem_pages > 0) { | |
1885 | struct page *tmp; | |
1886 | ||
1887 | /* Copy of the page will be stored in high memory */ | |
1888 | kaddr = buffer; | |
1889 | tmp = pfn_to_page(memory_bm_next_pfn(safe_highmem_bm)); | |
1890 | safe_highmem_pages--; | |
1891 | last_highmem_page = tmp; | |
1892 | pbe->copy_page = tmp; | |
1893 | } else { | |
1894 | /* Copy of the page will be stored in normal memory */ | |
1895 | kaddr = safe_pages_list; | |
1896 | safe_pages_list = safe_pages_list->next; | |
1897 | pbe->copy_page = virt_to_page(kaddr); | |
1898 | } | |
1899 | pbe->next = highmem_pblist; | |
1900 | highmem_pblist = pbe; | |
1901 | return kaddr; | |
1902 | } | |
1903 | ||
1904 | /** | |
1905 | * copy_last_highmem_page - copy the contents of a highmem image from | |
1906 | * @buffer, where the caller of snapshot_write_next() has place them, | |
1907 | * to the right location represented by @last_highmem_page . | |
1908 | */ | |
1909 | ||
1910 | static void copy_last_highmem_page(void) | |
1911 | { | |
1912 | if (last_highmem_page) { | |
1913 | void *dst; | |
1914 | ||
1915 | dst = kmap_atomic(last_highmem_page, KM_USER0); | |
1916 | memcpy(dst, buffer, PAGE_SIZE); | |
1917 | kunmap_atomic(dst, KM_USER0); | |
1918 | last_highmem_page = NULL; | |
1919 | } | |
1920 | } | |
1921 | ||
1922 | static inline int last_highmem_page_copied(void) | |
1923 | { | |
1924 | return !last_highmem_page; | |
1925 | } | |
1926 | ||
1927 | static inline void free_highmem_data(void) | |
1928 | { | |
1929 | if (safe_highmem_bm) | |
1930 | memory_bm_free(safe_highmem_bm, PG_UNSAFE_CLEAR); | |
1931 | ||
1932 | if (buffer) | |
1933 | free_image_page(buffer, PG_UNSAFE_CLEAR); | |
1934 | } | |
1935 | #else | |
1936 | static inline int get_safe_write_buffer(void) { return 0; } | |
1937 | ||
1938 | static unsigned int | |
1939 | count_highmem_image_pages(struct memory_bitmap *bm) { return 0; } | |
1940 | ||
1941 | static inline int | |
1942 | prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p) | |
1943 | { | |
1944 | return 0; | |
1945 | } | |
1946 | ||
1947 | static inline void * | |
1948 | get_highmem_page_buffer(struct page *page, struct chain_allocator *ca) | |
1949 | { | |
69643279 | 1950 | return ERR_PTR(-EINVAL); |
8357376d RW |
1951 | } |
1952 | ||
1953 | static inline void copy_last_highmem_page(void) {} | |
1954 | static inline int last_highmem_page_copied(void) { return 1; } | |
1955 | static inline void free_highmem_data(void) {} | |
1956 | #endif /* CONFIG_HIGHMEM */ | |
1957 | ||
f577eb30 | 1958 | /** |
940864dd RW |
1959 | * prepare_image - use the memory bitmap @bm to mark the pages that will |
1960 | * be overwritten in the process of restoring the system memory state | |
1961 | * from the suspend image ("unsafe" pages) and allocate memory for the | |
1962 | * image. | |
968808b8 | 1963 | * |
940864dd RW |
1964 | * The idea is to allocate a new memory bitmap first and then allocate |
1965 | * as many pages as needed for the image data, but not to assign these | |
1966 | * pages to specific tasks initially. Instead, we just mark them as | |
8357376d RW |
1967 | * allocated and create a lists of "safe" pages that will be used |
1968 | * later. On systems with high memory a list of "safe" highmem pages is | |
1969 | * also created. | |
f577eb30 RW |
1970 | */ |
1971 | ||
940864dd RW |
1972 | #define PBES_PER_LINKED_PAGE (LINKED_PAGE_DATA_SIZE / sizeof(struct pbe)) |
1973 | ||
940864dd RW |
1974 | static int |
1975 | prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm) | |
f577eb30 | 1976 | { |
8357376d | 1977 | unsigned int nr_pages, nr_highmem; |
940864dd RW |
1978 | struct linked_page *sp_list, *lp; |
1979 | int error; | |
f577eb30 | 1980 | |
8357376d RW |
1981 | /* If there is no highmem, the buffer will not be necessary */ |
1982 | free_image_page(buffer, PG_UNSAFE_CLEAR); | |
1983 | buffer = NULL; | |
1984 | ||
1985 | nr_highmem = count_highmem_image_pages(bm); | |
940864dd RW |
1986 | error = mark_unsafe_pages(bm); |
1987 | if (error) | |
1988 | goto Free; | |
1989 | ||
1990 | error = memory_bm_create(new_bm, GFP_ATOMIC, PG_SAFE); | |
1991 | if (error) | |
1992 | goto Free; | |
1993 | ||
1994 | duplicate_memory_bitmap(new_bm, bm); | |
1995 | memory_bm_free(bm, PG_UNSAFE_KEEP); | |
8357376d RW |
1996 | if (nr_highmem > 0) { |
1997 | error = prepare_highmem_image(bm, &nr_highmem); | |
1998 | if (error) | |
1999 | goto Free; | |
2000 | } | |
940864dd RW |
2001 | /* Reserve some safe pages for potential later use. |
2002 | * | |
2003 | * NOTE: This way we make sure there will be enough safe pages for the | |
2004 | * chain_alloc() in get_buffer(). It is a bit wasteful, but | |
2005 | * nr_copy_pages cannot be greater than 50% of the memory anyway. | |
2006 | */ | |
2007 | sp_list = NULL; | |
2008 | /* nr_copy_pages cannot be lesser than allocated_unsafe_pages */ | |
8357376d | 2009 | nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages; |
940864dd RW |
2010 | nr_pages = DIV_ROUND_UP(nr_pages, PBES_PER_LINKED_PAGE); |
2011 | while (nr_pages > 0) { | |
8357376d | 2012 | lp = get_image_page(GFP_ATOMIC, PG_SAFE); |
940864dd | 2013 | if (!lp) { |
f577eb30 | 2014 | error = -ENOMEM; |
940864dd RW |
2015 | goto Free; |
2016 | } | |
2017 | lp->next = sp_list; | |
2018 | sp_list = lp; | |
2019 | nr_pages--; | |
f577eb30 | 2020 | } |
940864dd RW |
2021 | /* Preallocate memory for the image */ |
2022 | safe_pages_list = NULL; | |
8357376d | 2023 | nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages; |
940864dd RW |
2024 | while (nr_pages > 0) { |
2025 | lp = (struct linked_page *)get_zeroed_page(GFP_ATOMIC); | |
2026 | if (!lp) { | |
2027 | error = -ENOMEM; | |
2028 | goto Free; | |
2029 | } | |
7be98234 | 2030 | if (!swsusp_page_is_free(virt_to_page(lp))) { |
940864dd RW |
2031 | /* The page is "safe", add it to the list */ |
2032 | lp->next = safe_pages_list; | |
2033 | safe_pages_list = lp; | |
968808b8 | 2034 | } |
940864dd | 2035 | /* Mark the page as allocated */ |
7be98234 RW |
2036 | swsusp_set_page_forbidden(virt_to_page(lp)); |
2037 | swsusp_set_page_free(virt_to_page(lp)); | |
940864dd | 2038 | nr_pages--; |
968808b8 | 2039 | } |
940864dd RW |
2040 | /* Free the reserved safe pages so that chain_alloc() can use them */ |
2041 | while (sp_list) { | |
2042 | lp = sp_list->next; | |
2043 | free_image_page(sp_list, PG_UNSAFE_CLEAR); | |
2044 | sp_list = lp; | |
f577eb30 | 2045 | } |
940864dd RW |
2046 | return 0; |
2047 | ||
59a49335 | 2048 | Free: |
940864dd | 2049 | swsusp_free(); |
f577eb30 RW |
2050 | return error; |
2051 | } | |
2052 | ||
940864dd RW |
2053 | /** |
2054 | * get_buffer - compute the address that snapshot_write_next() should | |
2055 | * set for its caller to write to. | |
2056 | */ | |
2057 | ||
2058 | static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca) | |
968808b8 | 2059 | { |
940864dd | 2060 | struct pbe *pbe; |
69643279 RW |
2061 | struct page *page; |
2062 | unsigned long pfn = memory_bm_next_pfn(bm); | |
968808b8 | 2063 | |
69643279 RW |
2064 | if (pfn == BM_END_OF_MAP) |
2065 | return ERR_PTR(-EFAULT); | |
2066 | ||
2067 | page = pfn_to_page(pfn); | |
8357376d RW |
2068 | if (PageHighMem(page)) |
2069 | return get_highmem_page_buffer(page, ca); | |
2070 | ||
7be98234 | 2071 | if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page)) |
940864dd RW |
2072 | /* We have allocated the "original" page frame and we can |
2073 | * use it directly to store the loaded page. | |
968808b8 | 2074 | */ |
940864dd RW |
2075 | return page_address(page); |
2076 | ||
2077 | /* The "original" page frame has not been allocated and we have to | |
2078 | * use a "safe" page frame to store the loaded page. | |
968808b8 | 2079 | */ |
940864dd RW |
2080 | pbe = chain_alloc(ca, sizeof(struct pbe)); |
2081 | if (!pbe) { | |
2082 | swsusp_free(); | |
69643279 | 2083 | return ERR_PTR(-ENOMEM); |
940864dd | 2084 | } |
8357376d RW |
2085 | pbe->orig_address = page_address(page); |
2086 | pbe->address = safe_pages_list; | |
940864dd RW |
2087 | safe_pages_list = safe_pages_list->next; |
2088 | pbe->next = restore_pblist; | |
2089 | restore_pblist = pbe; | |
8357376d | 2090 | return pbe->address; |
968808b8 RW |
2091 | } |
2092 | ||
f577eb30 RW |
2093 | /** |
2094 | * snapshot_write_next - used for writing the system memory snapshot. | |
2095 | * | |
2096 | * On the first call to it @handle should point to a zeroed | |
2097 | * snapshot_handle structure. The structure gets updated and a pointer | |
2098 | * to it should be passed to this function every next time. | |
2099 | * | |
2100 | * The @count parameter should contain the number of bytes the caller | |
2101 | * wants to write to the image. It must not be zero. | |
2102 | * | |
2103 | * On success the function returns a positive number. Then, the caller | |
2104 | * is allowed to write up to the returned number of bytes to the memory | |
2105 | * location computed by the data_of() macro. The number returned | |
2106 | * may be smaller than @count, but this only happens if the write would | |
2107 | * cross a page boundary otherwise. | |
2108 | * | |
2109 | * The function returns 0 to indicate the "end of file" condition, | |
2110 | * and a negative number is returned on error. In such cases the | |
2111 | * structure pointed to by @handle is not updated and should not be used | |
2112 | * any more. | |
2113 | */ | |
2114 | ||
2115 | int snapshot_write_next(struct snapshot_handle *handle, size_t count) | |
2116 | { | |
940864dd | 2117 | static struct chain_allocator ca; |
f577eb30 RW |
2118 | int error = 0; |
2119 | ||
940864dd | 2120 | /* Check if we have already loaded the entire image */ |
fb13a28b | 2121 | if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages) |
f577eb30 | 2122 | return 0; |
940864dd | 2123 | |
8357376d RW |
2124 | if (handle->offset == 0) { |
2125 | if (!buffer) | |
2126 | /* This makes the buffer be freed by swsusp_free() */ | |
2127 | buffer = get_image_page(GFP_ATOMIC, PG_ANY); | |
2128 | ||
f577eb30 RW |
2129 | if (!buffer) |
2130 | return -ENOMEM; | |
8357376d | 2131 | |
f577eb30 | 2132 | handle->buffer = buffer; |
8357376d | 2133 | } |
546e0d27 | 2134 | handle->sync_read = 1; |
fb13a28b | 2135 | if (handle->prev < handle->cur) { |
940864dd RW |
2136 | if (handle->prev == 0) { |
2137 | error = load_header(buffer); | |
2138 | if (error) | |
2139 | return error; | |
2140 | ||
2141 | error = memory_bm_create(©_bm, GFP_ATOMIC, PG_ANY); | |
f577eb30 RW |
2142 | if (error) |
2143 | return error; | |
940864dd | 2144 | |
f577eb30 | 2145 | } else if (handle->prev <= nr_meta_pages) { |
69643279 RW |
2146 | error = unpack_orig_pfns(buffer, ©_bm); |
2147 | if (error) | |
2148 | return error; | |
2149 | ||
940864dd RW |
2150 | if (handle->prev == nr_meta_pages) { |
2151 | error = prepare_image(&orig_bm, ©_bm); | |
f577eb30 RW |
2152 | if (error) |
2153 | return error; | |
940864dd RW |
2154 | |
2155 | chain_init(&ca, GFP_ATOMIC, PG_SAFE); | |
2156 | memory_bm_position_reset(&orig_bm); | |
2157 | restore_pblist = NULL; | |
2158 | handle->buffer = get_buffer(&orig_bm, &ca); | |
546e0d27 | 2159 | handle->sync_read = 0; |
69643279 RW |
2160 | if (IS_ERR(handle->buffer)) |
2161 | return PTR_ERR(handle->buffer); | |
f577eb30 RW |
2162 | } |
2163 | } else { | |
8357376d | 2164 | copy_last_highmem_page(); |
940864dd | 2165 | handle->buffer = get_buffer(&orig_bm, &ca); |
69643279 RW |
2166 | if (IS_ERR(handle->buffer)) |
2167 | return PTR_ERR(handle->buffer); | |
8357376d RW |
2168 | if (handle->buffer != buffer) |
2169 | handle->sync_read = 0; | |
f577eb30 | 2170 | } |
fb13a28b | 2171 | handle->prev = handle->cur; |
f577eb30 | 2172 | } |
fb13a28b RW |
2173 | handle->buf_offset = handle->cur_offset; |
2174 | if (handle->cur_offset + count >= PAGE_SIZE) { | |
2175 | count = PAGE_SIZE - handle->cur_offset; | |
2176 | handle->cur_offset = 0; | |
2177 | handle->cur++; | |
f577eb30 | 2178 | } else { |
fb13a28b | 2179 | handle->cur_offset += count; |
f577eb30 RW |
2180 | } |
2181 | handle->offset += count; | |
2182 | return count; | |
2183 | } | |
2184 | ||
8357376d RW |
2185 | /** |
2186 | * snapshot_write_finalize - must be called after the last call to | |
2187 | * snapshot_write_next() in case the last page in the image happens | |
2188 | * to be a highmem page and its contents should be stored in the | |
2189 | * highmem. Additionally, it releases the memory that will not be | |
2190 | * used any more. | |
2191 | */ | |
2192 | ||
2193 | void snapshot_write_finalize(struct snapshot_handle *handle) | |
2194 | { | |
2195 | copy_last_highmem_page(); | |
2196 | /* Free only if we have loaded the image entirely */ | |
2197 | if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages) { | |
2198 | memory_bm_free(&orig_bm, PG_UNSAFE_CLEAR); | |
2199 | free_highmem_data(); | |
2200 | } | |
2201 | } | |
2202 | ||
f577eb30 RW |
2203 | int snapshot_image_loaded(struct snapshot_handle *handle) |
2204 | { | |
8357376d | 2205 | return !(!nr_copy_pages || !last_highmem_page_copied() || |
940864dd RW |
2206 | handle->cur <= nr_meta_pages + nr_copy_pages); |
2207 | } | |
2208 | ||
8357376d RW |
2209 | #ifdef CONFIG_HIGHMEM |
2210 | /* Assumes that @buf is ready and points to a "safe" page */ | |
2211 | static inline void | |
2212 | swap_two_pages_data(struct page *p1, struct page *p2, void *buf) | |
940864dd | 2213 | { |
8357376d RW |
2214 | void *kaddr1, *kaddr2; |
2215 | ||
2216 | kaddr1 = kmap_atomic(p1, KM_USER0); | |
2217 | kaddr2 = kmap_atomic(p2, KM_USER1); | |
2218 | memcpy(buf, kaddr1, PAGE_SIZE); | |
2219 | memcpy(kaddr1, kaddr2, PAGE_SIZE); | |
2220 | memcpy(kaddr2, buf, PAGE_SIZE); | |
2221 | kunmap_atomic(kaddr1, KM_USER0); | |
2222 | kunmap_atomic(kaddr2, KM_USER1); | |
2223 | } | |
2224 | ||
2225 | /** | |
2226 | * restore_highmem - for each highmem page that was allocated before | |
2227 | * the suspend and included in the suspend image, and also has been | |
2228 | * allocated by the "resume" kernel swap its current (ie. "before | |
2229 | * resume") contents with the previous (ie. "before suspend") one. | |
2230 | * | |
2231 | * If the resume eventually fails, we can call this function once | |
2232 | * again and restore the "before resume" highmem state. | |
2233 | */ | |
2234 | ||
2235 | int restore_highmem(void) | |
2236 | { | |
2237 | struct highmem_pbe *pbe = highmem_pblist; | |
2238 | void *buf; | |
2239 | ||
2240 | if (!pbe) | |
2241 | return 0; | |
2242 | ||
2243 | buf = get_image_page(GFP_ATOMIC, PG_SAFE); | |
2244 | if (!buf) | |
2245 | return -ENOMEM; | |
2246 | ||
2247 | while (pbe) { | |
2248 | swap_two_pages_data(pbe->copy_page, pbe->orig_page, buf); | |
2249 | pbe = pbe->next; | |
2250 | } | |
2251 | free_image_page(buf, PG_UNSAFE_CLEAR); | |
2252 | return 0; | |
f577eb30 | 2253 | } |
8357376d | 2254 | #endif /* CONFIG_HIGHMEM */ |