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 | ||
8357376d RW |
42 | /* List of PBEs needed for restoring the pages that were allocated before |
43 | * the suspend and included in the suspend image, but have also been | |
44 | * allocated by the "resume" kernel, so their contents cannot be written | |
45 | * directly to their "original" page frames. | |
46 | */ | |
75534b50 RW |
47 | struct pbe *restore_pblist; |
48 | ||
8357376d | 49 | /* Pointer to an auxiliary buffer (1 page) */ |
940864dd | 50 | static void *buffer; |
7088a5c0 | 51 | |
f6143aa6 RW |
52 | /** |
53 | * @safe_needed - on resume, for storing the PBE list and the image, | |
54 | * we can only use memory pages that do not conflict with the pages | |
8357376d RW |
55 | * used before suspend. The unsafe pages have PageNosaveFree set |
56 | * and we count them using unsafe_pages. | |
f6143aa6 | 57 | * |
8357376d RW |
58 | * Each allocated image page is marked as PageNosave and PageNosaveFree |
59 | * so that swsusp_free() can release it. | |
f6143aa6 RW |
60 | */ |
61 | ||
0bcd888d RW |
62 | #define PG_ANY 0 |
63 | #define PG_SAFE 1 | |
64 | #define PG_UNSAFE_CLEAR 1 | |
65 | #define PG_UNSAFE_KEEP 0 | |
66 | ||
940864dd | 67 | static unsigned int allocated_unsafe_pages; |
f6143aa6 | 68 | |
8357376d | 69 | static void *get_image_page(gfp_t gfp_mask, int safe_needed) |
f6143aa6 RW |
70 | { |
71 | void *res; | |
72 | ||
73 | res = (void *)get_zeroed_page(gfp_mask); | |
74 | if (safe_needed) | |
7be98234 | 75 | while (res && swsusp_page_is_free(virt_to_page(res))) { |
f6143aa6 | 76 | /* The page is unsafe, mark it for swsusp_free() */ |
7be98234 | 77 | swsusp_set_page_forbidden(virt_to_page(res)); |
940864dd | 78 | allocated_unsafe_pages++; |
f6143aa6 RW |
79 | res = (void *)get_zeroed_page(gfp_mask); |
80 | } | |
81 | if (res) { | |
7be98234 RW |
82 | swsusp_set_page_forbidden(virt_to_page(res)); |
83 | swsusp_set_page_free(virt_to_page(res)); | |
f6143aa6 RW |
84 | } |
85 | return res; | |
86 | } | |
87 | ||
88 | unsigned long get_safe_page(gfp_t gfp_mask) | |
89 | { | |
8357376d RW |
90 | return (unsigned long)get_image_page(gfp_mask, PG_SAFE); |
91 | } | |
92 | ||
5b6d15de RW |
93 | static struct page *alloc_image_page(gfp_t gfp_mask) |
94 | { | |
8357376d RW |
95 | struct page *page; |
96 | ||
97 | page = alloc_page(gfp_mask); | |
98 | if (page) { | |
7be98234 RW |
99 | swsusp_set_page_forbidden(page); |
100 | swsusp_set_page_free(page); | |
8357376d RW |
101 | } |
102 | return page; | |
f6143aa6 RW |
103 | } |
104 | ||
105 | /** | |
106 | * free_image_page - free page represented by @addr, allocated with | |
8357376d | 107 | * get_image_page (page flags set by it must be cleared) |
f6143aa6 RW |
108 | */ |
109 | ||
110 | static inline void free_image_page(void *addr, int clear_nosave_free) | |
111 | { | |
8357376d RW |
112 | struct page *page; |
113 | ||
114 | BUG_ON(!virt_addr_valid(addr)); | |
115 | ||
116 | page = virt_to_page(addr); | |
117 | ||
7be98234 | 118 | swsusp_unset_page_forbidden(page); |
f6143aa6 | 119 | if (clear_nosave_free) |
7be98234 | 120 | swsusp_unset_page_free(page); |
8357376d RW |
121 | |
122 | __free_page(page); | |
f6143aa6 RW |
123 | } |
124 | ||
b788db79 RW |
125 | /* struct linked_page is used to build chains of pages */ |
126 | ||
127 | #define LINKED_PAGE_DATA_SIZE (PAGE_SIZE - sizeof(void *)) | |
128 | ||
129 | struct linked_page { | |
130 | struct linked_page *next; | |
131 | char data[LINKED_PAGE_DATA_SIZE]; | |
132 | } __attribute__((packed)); | |
133 | ||
134 | static inline void | |
135 | free_list_of_pages(struct linked_page *list, int clear_page_nosave) | |
136 | { | |
137 | while (list) { | |
138 | struct linked_page *lp = list->next; | |
139 | ||
140 | free_image_page(list, clear_page_nosave); | |
141 | list = lp; | |
142 | } | |
143 | } | |
144 | ||
145 | /** | |
146 | * struct chain_allocator is used for allocating small objects out of | |
147 | * a linked list of pages called 'the chain'. | |
148 | * | |
149 | * The chain grows each time when there is no room for a new object in | |
150 | * the current page. The allocated objects cannot be freed individually. | |
151 | * It is only possible to free them all at once, by freeing the entire | |
152 | * chain. | |
153 | * | |
154 | * NOTE: The chain allocator may be inefficient if the allocated objects | |
155 | * are not much smaller than PAGE_SIZE. | |
156 | */ | |
157 | ||
158 | struct chain_allocator { | |
159 | struct linked_page *chain; /* the chain */ | |
160 | unsigned int used_space; /* total size of objects allocated out | |
161 | * of the current page | |
162 | */ | |
163 | gfp_t gfp_mask; /* mask for allocating pages */ | |
164 | int safe_needed; /* if set, only "safe" pages are allocated */ | |
165 | }; | |
166 | ||
167 | static void | |
168 | chain_init(struct chain_allocator *ca, gfp_t gfp_mask, int safe_needed) | |
169 | { | |
170 | ca->chain = NULL; | |
171 | ca->used_space = LINKED_PAGE_DATA_SIZE; | |
172 | ca->gfp_mask = gfp_mask; | |
173 | ca->safe_needed = safe_needed; | |
174 | } | |
175 | ||
176 | static void *chain_alloc(struct chain_allocator *ca, unsigned int size) | |
177 | { | |
178 | void *ret; | |
179 | ||
180 | if (LINKED_PAGE_DATA_SIZE - ca->used_space < size) { | |
181 | struct linked_page *lp; | |
182 | ||
8357376d | 183 | lp = get_image_page(ca->gfp_mask, ca->safe_needed); |
b788db79 RW |
184 | if (!lp) |
185 | return NULL; | |
186 | ||
187 | lp->next = ca->chain; | |
188 | ca->chain = lp; | |
189 | ca->used_space = 0; | |
190 | } | |
191 | ret = ca->chain->data + ca->used_space; | |
192 | ca->used_space += size; | |
193 | return ret; | |
194 | } | |
195 | ||
b788db79 RW |
196 | /** |
197 | * Data types related to memory bitmaps. | |
198 | * | |
199 | * Memory bitmap is a structure consiting of many linked lists of | |
200 | * objects. The main list's elements are of type struct zone_bitmap | |
201 | * and each of them corresonds to one zone. For each zone bitmap | |
202 | * object there is a list of objects of type struct bm_block that | |
0d83304c | 203 | * represent each blocks of bitmap in which information is stored. |
b788db79 RW |
204 | * |
205 | * struct memory_bitmap contains a pointer to the main list of zone | |
206 | * bitmap objects, a struct bm_position used for browsing the bitmap, | |
207 | * and a pointer to the list of pages used for allocating all of the | |
208 | * zone bitmap objects and bitmap block objects. | |
209 | * | |
210 | * NOTE: It has to be possible to lay out the bitmap in memory | |
211 | * using only allocations of order 0. Additionally, the bitmap is | |
212 | * designed to work with arbitrary number of zones (this is over the | |
213 | * top for now, but let's avoid making unnecessary assumptions ;-). | |
214 | * | |
215 | * struct zone_bitmap contains a pointer to a list of bitmap block | |
216 | * objects and a pointer to the bitmap block object that has been | |
217 | * most recently used for setting bits. Additionally, it contains the | |
218 | * pfns that correspond to the start and end of the represented zone. | |
219 | * | |
220 | * struct bm_block contains a pointer to the memory page in which | |
0d83304c AM |
221 | * information is stored (in the form of a block of bitmap) |
222 | * It also contains the pfns that correspond to the start and end of | |
223 | * the represented memory area. | |
b788db79 RW |
224 | */ |
225 | ||
226 | #define BM_END_OF_MAP (~0UL) | |
227 | ||
b788db79 RW |
228 | #define BM_BITS_PER_BLOCK (PAGE_SIZE << 3) |
229 | ||
230 | struct bm_block { | |
846705de | 231 | struct list_head hook; /* hook into a list of bitmap blocks */ |
b788db79 RW |
232 | unsigned long start_pfn; /* pfn represented by the first bit */ |
233 | unsigned long end_pfn; /* pfn represented by the last bit plus 1 */ | |
0d83304c | 234 | unsigned long *data; /* bitmap representing pages */ |
b788db79 RW |
235 | }; |
236 | ||
0d83304c AM |
237 | static inline unsigned long bm_block_bits(struct bm_block *bb) |
238 | { | |
239 | return bb->end_pfn - bb->start_pfn; | |
240 | } | |
241 | ||
b788db79 RW |
242 | /* strcut bm_position is used for browsing memory bitmaps */ |
243 | ||
244 | struct bm_position { | |
b788db79 | 245 | struct bm_block *block; |
b788db79 RW |
246 | int bit; |
247 | }; | |
248 | ||
249 | struct memory_bitmap { | |
846705de | 250 | struct list_head blocks; /* list of bitmap blocks */ |
b788db79 RW |
251 | struct linked_page *p_list; /* list of pages used to store zone |
252 | * bitmap objects and bitmap block | |
253 | * objects | |
254 | */ | |
255 | struct bm_position cur; /* most recently used bit position */ | |
256 | }; | |
257 | ||
258 | /* Functions that operate on memory bitmaps */ | |
259 | ||
b788db79 RW |
260 | static void memory_bm_position_reset(struct memory_bitmap *bm) |
261 | { | |
846705de | 262 | bm->cur.block = list_entry(bm->blocks.next, struct bm_block, hook); |
0d83304c | 263 | bm->cur.bit = 0; |
b788db79 RW |
264 | } |
265 | ||
266 | static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free); | |
267 | ||
268 | /** | |
269 | * create_bm_block_list - create a list of block bitmap objects | |
846705de RW |
270 | * @nr_blocks - number of blocks to allocate |
271 | * @list - list to put the allocated blocks into | |
272 | * @ca - chain allocator to be used for allocating memory | |
b788db79 | 273 | */ |
846705de RW |
274 | static int create_bm_block_list(unsigned long pages, |
275 | struct list_head *list, | |
276 | struct chain_allocator *ca) | |
b788db79 | 277 | { |
846705de | 278 | unsigned int nr_blocks = DIV_ROUND_UP(pages, BM_BITS_PER_BLOCK); |
b788db79 RW |
279 | |
280 | while (nr_blocks-- > 0) { | |
281 | struct bm_block *bb; | |
282 | ||
283 | bb = chain_alloc(ca, sizeof(struct bm_block)); | |
284 | if (!bb) | |
846705de RW |
285 | return -ENOMEM; |
286 | list_add(&bb->hook, list); | |
b788db79 | 287 | } |
846705de RW |
288 | |
289 | return 0; | |
b788db79 RW |
290 | } |
291 | ||
846705de RW |
292 | struct mem_extent { |
293 | struct list_head hook; | |
294 | unsigned long start; | |
295 | unsigned long end; | |
296 | }; | |
297 | ||
b788db79 | 298 | /** |
846705de RW |
299 | * free_mem_extents - free a list of memory extents |
300 | * @list - list of extents to empty | |
b788db79 | 301 | */ |
846705de RW |
302 | static void free_mem_extents(struct list_head *list) |
303 | { | |
304 | struct mem_extent *ext, *aux; | |
b788db79 | 305 | |
846705de RW |
306 | list_for_each_entry_safe(ext, aux, list, hook) { |
307 | list_del(&ext->hook); | |
308 | kfree(ext); | |
309 | } | |
310 | } | |
311 | ||
312 | /** | |
313 | * create_mem_extents - create a list of memory extents representing | |
314 | * contiguous ranges of PFNs | |
315 | * @list - list to put the extents into | |
316 | * @gfp_mask - mask to use for memory allocations | |
317 | */ | |
318 | static int create_mem_extents(struct list_head *list, gfp_t gfp_mask) | |
b788db79 | 319 | { |
846705de | 320 | struct zone *zone; |
b788db79 | 321 | |
846705de | 322 | INIT_LIST_HEAD(list); |
b788db79 | 323 | |
ee99c71c | 324 | for_each_populated_zone(zone) { |
846705de RW |
325 | unsigned long zone_start, zone_end; |
326 | struct mem_extent *ext, *cur, *aux; | |
327 | ||
846705de RW |
328 | zone_start = zone->zone_start_pfn; |
329 | zone_end = zone->zone_start_pfn + zone->spanned_pages; | |
330 | ||
331 | list_for_each_entry(ext, list, hook) | |
332 | if (zone_start <= ext->end) | |
333 | break; | |
b788db79 | 334 | |
846705de RW |
335 | if (&ext->hook == list || zone_end < ext->start) { |
336 | /* New extent is necessary */ | |
337 | struct mem_extent *new_ext; | |
338 | ||
339 | new_ext = kzalloc(sizeof(struct mem_extent), gfp_mask); | |
340 | if (!new_ext) { | |
341 | free_mem_extents(list); | |
342 | return -ENOMEM; | |
343 | } | |
344 | new_ext->start = zone_start; | |
345 | new_ext->end = zone_end; | |
346 | list_add_tail(&new_ext->hook, &ext->hook); | |
347 | continue; | |
348 | } | |
349 | ||
350 | /* Merge this zone's range of PFNs with the existing one */ | |
351 | if (zone_start < ext->start) | |
352 | ext->start = zone_start; | |
353 | if (zone_end > ext->end) | |
354 | ext->end = zone_end; | |
355 | ||
356 | /* More merging may be possible */ | |
357 | cur = ext; | |
358 | list_for_each_entry_safe_continue(cur, aux, list, hook) { | |
359 | if (zone_end < cur->start) | |
360 | break; | |
361 | if (zone_end < cur->end) | |
362 | ext->end = cur->end; | |
363 | list_del(&cur->hook); | |
364 | kfree(cur); | |
365 | } | |
b788db79 | 366 | } |
846705de RW |
367 | |
368 | return 0; | |
b788db79 RW |
369 | } |
370 | ||
371 | /** | |
372 | * memory_bm_create - allocate memory for a memory bitmap | |
373 | */ | |
b788db79 RW |
374 | static int |
375 | memory_bm_create(struct memory_bitmap *bm, gfp_t gfp_mask, int safe_needed) | |
376 | { | |
377 | struct chain_allocator ca; | |
846705de RW |
378 | struct list_head mem_extents; |
379 | struct mem_extent *ext; | |
380 | int error; | |
b788db79 RW |
381 | |
382 | chain_init(&ca, gfp_mask, safe_needed); | |
846705de | 383 | INIT_LIST_HEAD(&bm->blocks); |
b788db79 | 384 | |
846705de RW |
385 | error = create_mem_extents(&mem_extents, gfp_mask); |
386 | if (error) | |
387 | return error; | |
b788db79 | 388 | |
846705de RW |
389 | list_for_each_entry(ext, &mem_extents, hook) { |
390 | struct bm_block *bb; | |
391 | unsigned long pfn = ext->start; | |
392 | unsigned long pages = ext->end - ext->start; | |
b788db79 | 393 | |
846705de | 394 | bb = list_entry(bm->blocks.prev, struct bm_block, hook); |
b788db79 | 395 | |
846705de RW |
396 | error = create_bm_block_list(pages, bm->blocks.prev, &ca); |
397 | if (error) | |
398 | goto Error; | |
b788db79 | 399 | |
846705de RW |
400 | list_for_each_entry_continue(bb, &bm->blocks, hook) { |
401 | bb->data = get_image_page(gfp_mask, safe_needed); | |
402 | if (!bb->data) { | |
403 | error = -ENOMEM; | |
404 | goto Error; | |
405 | } | |
b788db79 RW |
406 | |
407 | bb->start_pfn = pfn; | |
846705de | 408 | if (pages >= BM_BITS_PER_BLOCK) { |
b788db79 | 409 | pfn += BM_BITS_PER_BLOCK; |
846705de | 410 | pages -= BM_BITS_PER_BLOCK; |
b788db79 RW |
411 | } else { |
412 | /* This is executed only once in the loop */ | |
846705de | 413 | pfn += pages; |
b788db79 RW |
414 | } |
415 | bb->end_pfn = pfn; | |
b788db79 | 416 | } |
b788db79 | 417 | } |
846705de | 418 | |
b788db79 RW |
419 | bm->p_list = ca.chain; |
420 | memory_bm_position_reset(bm); | |
846705de RW |
421 | Exit: |
422 | free_mem_extents(&mem_extents); | |
423 | return error; | |
b788db79 | 424 | |
846705de | 425 | Error: |
b788db79 RW |
426 | bm->p_list = ca.chain; |
427 | memory_bm_free(bm, PG_UNSAFE_CLEAR); | |
846705de | 428 | goto Exit; |
b788db79 RW |
429 | } |
430 | ||
431 | /** | |
432 | * memory_bm_free - free memory occupied by the memory bitmap @bm | |
433 | */ | |
b788db79 RW |
434 | static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free) |
435 | { | |
846705de | 436 | struct bm_block *bb; |
b788db79 | 437 | |
846705de RW |
438 | list_for_each_entry(bb, &bm->blocks, hook) |
439 | if (bb->data) | |
440 | free_image_page(bb->data, clear_nosave_free); | |
b788db79 | 441 | |
b788db79 | 442 | free_list_of_pages(bm->p_list, clear_nosave_free); |
846705de RW |
443 | |
444 | INIT_LIST_HEAD(&bm->blocks); | |
b788db79 RW |
445 | } |
446 | ||
447 | /** | |
74dfd666 | 448 | * memory_bm_find_bit - find the bit in the bitmap @bm that corresponds |
b788db79 RW |
449 | * to given pfn. The cur_zone_bm member of @bm and the cur_block member |
450 | * of @bm->cur_zone_bm are updated. | |
b788db79 | 451 | */ |
a82f7119 | 452 | static int memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn, |
74dfd666 | 453 | void **addr, unsigned int *bit_nr) |
b788db79 | 454 | { |
b788db79 RW |
455 | struct bm_block *bb; |
456 | ||
846705de RW |
457 | /* |
458 | * Check if the pfn corresponds to the current bitmap block and find | |
459 | * the block where it fits if this is not the case. | |
460 | */ | |
461 | bb = bm->cur.block; | |
b788db79 | 462 | if (pfn < bb->start_pfn) |
846705de RW |
463 | list_for_each_entry_continue_reverse(bb, &bm->blocks, hook) |
464 | if (pfn >= bb->start_pfn) | |
465 | break; | |
b788db79 | 466 | |
846705de RW |
467 | if (pfn >= bb->end_pfn) |
468 | list_for_each_entry_continue(bb, &bm->blocks, hook) | |
469 | if (pfn >= bb->start_pfn && pfn < bb->end_pfn) | |
470 | break; | |
74dfd666 | 471 | |
846705de RW |
472 | if (&bb->hook == &bm->blocks) |
473 | return -EFAULT; | |
474 | ||
475 | /* The block has been found */ | |
476 | bm->cur.block = bb; | |
b788db79 | 477 | pfn -= bb->start_pfn; |
846705de | 478 | bm->cur.bit = pfn + 1; |
0d83304c AM |
479 | *bit_nr = pfn; |
480 | *addr = bb->data; | |
a82f7119 | 481 | return 0; |
74dfd666 RW |
482 | } |
483 | ||
484 | static void memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn) | |
485 | { | |
486 | void *addr; | |
487 | unsigned int bit; | |
a82f7119 | 488 | int error; |
74dfd666 | 489 | |
a82f7119 RW |
490 | error = memory_bm_find_bit(bm, pfn, &addr, &bit); |
491 | BUG_ON(error); | |
74dfd666 RW |
492 | set_bit(bit, addr); |
493 | } | |
494 | ||
a82f7119 RW |
495 | static int mem_bm_set_bit_check(struct memory_bitmap *bm, unsigned long pfn) |
496 | { | |
497 | void *addr; | |
498 | unsigned int bit; | |
499 | int error; | |
500 | ||
501 | error = memory_bm_find_bit(bm, pfn, &addr, &bit); | |
502 | if (!error) | |
503 | set_bit(bit, addr); | |
504 | return error; | |
505 | } | |
506 | ||
74dfd666 RW |
507 | static void memory_bm_clear_bit(struct memory_bitmap *bm, unsigned long pfn) |
508 | { | |
509 | void *addr; | |
510 | unsigned int bit; | |
a82f7119 | 511 | int error; |
74dfd666 | 512 | |
a82f7119 RW |
513 | error = memory_bm_find_bit(bm, pfn, &addr, &bit); |
514 | BUG_ON(error); | |
74dfd666 RW |
515 | clear_bit(bit, addr); |
516 | } | |
517 | ||
518 | static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn) | |
519 | { | |
520 | void *addr; | |
521 | unsigned int bit; | |
a82f7119 | 522 | int error; |
74dfd666 | 523 | |
a82f7119 RW |
524 | error = memory_bm_find_bit(bm, pfn, &addr, &bit); |
525 | BUG_ON(error); | |
74dfd666 | 526 | return test_bit(bit, addr); |
b788db79 RW |
527 | } |
528 | ||
69643279 RW |
529 | static bool memory_bm_pfn_present(struct memory_bitmap *bm, unsigned long pfn) |
530 | { | |
531 | void *addr; | |
532 | unsigned int bit; | |
533 | ||
534 | return !memory_bm_find_bit(bm, pfn, &addr, &bit); | |
535 | } | |
536 | ||
b788db79 RW |
537 | /** |
538 | * memory_bm_next_pfn - find the pfn that corresponds to the next set bit | |
539 | * in the bitmap @bm. If the pfn cannot be found, BM_END_OF_MAP is | |
540 | * returned. | |
541 | * | |
542 | * It is required to run memory_bm_position_reset() before the first call to | |
543 | * this function. | |
544 | */ | |
545 | ||
546 | static unsigned long memory_bm_next_pfn(struct memory_bitmap *bm) | |
547 | { | |
b788db79 | 548 | struct bm_block *bb; |
b788db79 RW |
549 | int bit; |
550 | ||
846705de | 551 | bb = bm->cur.block; |
b788db79 | 552 | do { |
846705de RW |
553 | bit = bm->cur.bit; |
554 | bit = find_next_bit(bb->data, bm_block_bits(bb), bit); | |
555 | if (bit < bm_block_bits(bb)) | |
556 | goto Return_pfn; | |
557 | ||
558 | bb = list_entry(bb->hook.next, struct bm_block, hook); | |
559 | bm->cur.block = bb; | |
560 | bm->cur.bit = 0; | |
561 | } while (&bb->hook != &bm->blocks); | |
562 | ||
b788db79 RW |
563 | memory_bm_position_reset(bm); |
564 | return BM_END_OF_MAP; | |
565 | ||
59a49335 | 566 | Return_pfn: |
0d83304c AM |
567 | bm->cur.bit = bit + 1; |
568 | return bb->start_pfn + bit; | |
b788db79 RW |
569 | } |
570 | ||
74dfd666 RW |
571 | /** |
572 | * This structure represents a range of page frames the contents of which | |
573 | * should not be saved during the suspend. | |
574 | */ | |
575 | ||
576 | struct nosave_region { | |
577 | struct list_head list; | |
578 | unsigned long start_pfn; | |
579 | unsigned long end_pfn; | |
580 | }; | |
581 | ||
582 | static LIST_HEAD(nosave_regions); | |
583 | ||
584 | /** | |
585 | * register_nosave_region - register a range of page frames the contents | |
586 | * of which should not be saved during the suspend (to be used in the early | |
587 | * initialization code) | |
588 | */ | |
589 | ||
590 | void __init | |
940d67f6 JB |
591 | __register_nosave_region(unsigned long start_pfn, unsigned long end_pfn, |
592 | int use_kmalloc) | |
74dfd666 RW |
593 | { |
594 | struct nosave_region *region; | |
595 | ||
596 | if (start_pfn >= end_pfn) | |
597 | return; | |
598 | ||
599 | if (!list_empty(&nosave_regions)) { | |
600 | /* Try to extend the previous region (they should be sorted) */ | |
601 | region = list_entry(nosave_regions.prev, | |
602 | struct nosave_region, list); | |
603 | if (region->end_pfn == start_pfn) { | |
604 | region->end_pfn = end_pfn; | |
605 | goto Report; | |
606 | } | |
607 | } | |
940d67f6 JB |
608 | if (use_kmalloc) { |
609 | /* during init, this shouldn't fail */ | |
610 | region = kmalloc(sizeof(struct nosave_region), GFP_KERNEL); | |
611 | BUG_ON(!region); | |
612 | } else | |
613 | /* This allocation cannot fail */ | |
614 | region = alloc_bootmem_low(sizeof(struct nosave_region)); | |
74dfd666 RW |
615 | region->start_pfn = start_pfn; |
616 | region->end_pfn = end_pfn; | |
617 | list_add_tail(®ion->list, &nosave_regions); | |
618 | Report: | |
23976728 | 619 | printk(KERN_INFO "PM: Registered nosave memory: %016lx - %016lx\n", |
74dfd666 RW |
620 | start_pfn << PAGE_SHIFT, end_pfn << PAGE_SHIFT); |
621 | } | |
622 | ||
623 | /* | |
624 | * Set bits in this map correspond to the page frames the contents of which | |
625 | * should not be saved during the suspend. | |
626 | */ | |
627 | static struct memory_bitmap *forbidden_pages_map; | |
628 | ||
629 | /* Set bits in this map correspond to free page frames. */ | |
630 | static struct memory_bitmap *free_pages_map; | |
631 | ||
632 | /* | |
633 | * Each page frame allocated for creating the image is marked by setting the | |
634 | * corresponding bits in forbidden_pages_map and free_pages_map simultaneously | |
635 | */ | |
636 | ||
637 | void swsusp_set_page_free(struct page *page) | |
638 | { | |
639 | if (free_pages_map) | |
640 | memory_bm_set_bit(free_pages_map, page_to_pfn(page)); | |
641 | } | |
642 | ||
643 | static int swsusp_page_is_free(struct page *page) | |
644 | { | |
645 | return free_pages_map ? | |
646 | memory_bm_test_bit(free_pages_map, page_to_pfn(page)) : 0; | |
647 | } | |
648 | ||
649 | void swsusp_unset_page_free(struct page *page) | |
650 | { | |
651 | if (free_pages_map) | |
652 | memory_bm_clear_bit(free_pages_map, page_to_pfn(page)); | |
653 | } | |
654 | ||
655 | static void swsusp_set_page_forbidden(struct page *page) | |
656 | { | |
657 | if (forbidden_pages_map) | |
658 | memory_bm_set_bit(forbidden_pages_map, page_to_pfn(page)); | |
659 | } | |
660 | ||
661 | int swsusp_page_is_forbidden(struct page *page) | |
662 | { | |
663 | return forbidden_pages_map ? | |
664 | memory_bm_test_bit(forbidden_pages_map, page_to_pfn(page)) : 0; | |
665 | } | |
666 | ||
667 | static void swsusp_unset_page_forbidden(struct page *page) | |
668 | { | |
669 | if (forbidden_pages_map) | |
670 | memory_bm_clear_bit(forbidden_pages_map, page_to_pfn(page)); | |
671 | } | |
672 | ||
673 | /** | |
674 | * mark_nosave_pages - set bits corresponding to the page frames the | |
675 | * contents of which should not be saved in a given bitmap. | |
676 | */ | |
677 | ||
678 | static void mark_nosave_pages(struct memory_bitmap *bm) | |
679 | { | |
680 | struct nosave_region *region; | |
681 | ||
682 | if (list_empty(&nosave_regions)) | |
683 | return; | |
684 | ||
685 | list_for_each_entry(region, &nosave_regions, list) { | |
686 | unsigned long pfn; | |
687 | ||
23976728 | 688 | pr_debug("PM: Marking nosave pages: %016lx - %016lx\n", |
74dfd666 RW |
689 | region->start_pfn << PAGE_SHIFT, |
690 | region->end_pfn << PAGE_SHIFT); | |
691 | ||
692 | for (pfn = region->start_pfn; pfn < region->end_pfn; pfn++) | |
a82f7119 RW |
693 | if (pfn_valid(pfn)) { |
694 | /* | |
695 | * It is safe to ignore the result of | |
696 | * mem_bm_set_bit_check() here, since we won't | |
697 | * touch the PFNs for which the error is | |
698 | * returned anyway. | |
699 | */ | |
700 | mem_bm_set_bit_check(bm, pfn); | |
701 | } | |
74dfd666 RW |
702 | } |
703 | } | |
704 | ||
705 | /** | |
706 | * create_basic_memory_bitmaps - create bitmaps needed for marking page | |
707 | * frames that should not be saved and free page frames. The pointers | |
708 | * forbidden_pages_map and free_pages_map are only modified if everything | |
709 | * goes well, because we don't want the bits to be used before both bitmaps | |
710 | * are set up. | |
711 | */ | |
712 | ||
713 | int create_basic_memory_bitmaps(void) | |
714 | { | |
715 | struct memory_bitmap *bm1, *bm2; | |
716 | int error = 0; | |
717 | ||
718 | BUG_ON(forbidden_pages_map || free_pages_map); | |
719 | ||
0709db60 | 720 | bm1 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL); |
74dfd666 RW |
721 | if (!bm1) |
722 | return -ENOMEM; | |
723 | ||
0709db60 | 724 | error = memory_bm_create(bm1, GFP_KERNEL, PG_ANY); |
74dfd666 RW |
725 | if (error) |
726 | goto Free_first_object; | |
727 | ||
0709db60 | 728 | bm2 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL); |
74dfd666 RW |
729 | if (!bm2) |
730 | goto Free_first_bitmap; | |
731 | ||
0709db60 | 732 | error = memory_bm_create(bm2, GFP_KERNEL, PG_ANY); |
74dfd666 RW |
733 | if (error) |
734 | goto Free_second_object; | |
735 | ||
736 | forbidden_pages_map = bm1; | |
737 | free_pages_map = bm2; | |
738 | mark_nosave_pages(forbidden_pages_map); | |
739 | ||
23976728 | 740 | pr_debug("PM: Basic memory bitmaps created\n"); |
74dfd666 RW |
741 | |
742 | return 0; | |
743 | ||
744 | Free_second_object: | |
745 | kfree(bm2); | |
746 | Free_first_bitmap: | |
747 | memory_bm_free(bm1, PG_UNSAFE_CLEAR); | |
748 | Free_first_object: | |
749 | kfree(bm1); | |
750 | return -ENOMEM; | |
751 | } | |
752 | ||
753 | /** | |
754 | * free_basic_memory_bitmaps - free memory bitmaps allocated by | |
755 | * create_basic_memory_bitmaps(). The auxiliary pointers are necessary | |
756 | * so that the bitmaps themselves are not referred to while they are being | |
757 | * freed. | |
758 | */ | |
759 | ||
760 | void free_basic_memory_bitmaps(void) | |
761 | { | |
762 | struct memory_bitmap *bm1, *bm2; | |
763 | ||
764 | BUG_ON(!(forbidden_pages_map && free_pages_map)); | |
765 | ||
766 | bm1 = forbidden_pages_map; | |
767 | bm2 = free_pages_map; | |
768 | forbidden_pages_map = NULL; | |
769 | free_pages_map = NULL; | |
770 | memory_bm_free(bm1, PG_UNSAFE_CLEAR); | |
771 | kfree(bm1); | |
772 | memory_bm_free(bm2, PG_UNSAFE_CLEAR); | |
773 | kfree(bm2); | |
774 | ||
23976728 | 775 | pr_debug("PM: Basic memory bitmaps freed\n"); |
74dfd666 RW |
776 | } |
777 | ||
b788db79 RW |
778 | /** |
779 | * snapshot_additional_pages - estimate the number of additional pages | |
780 | * be needed for setting up the suspend image data structures for given | |
781 | * zone (usually the returned value is greater than the exact number) | |
782 | */ | |
783 | ||
784 | unsigned int snapshot_additional_pages(struct zone *zone) | |
785 | { | |
786 | unsigned int res; | |
787 | ||
788 | res = DIV_ROUND_UP(zone->spanned_pages, BM_BITS_PER_BLOCK); | |
789 | res += DIV_ROUND_UP(res * sizeof(struct bm_block), PAGE_SIZE); | |
8357376d | 790 | return 2 * res; |
b788db79 RW |
791 | } |
792 | ||
8357376d RW |
793 | #ifdef CONFIG_HIGHMEM |
794 | /** | |
795 | * count_free_highmem_pages - compute the total number of free highmem | |
796 | * pages, system-wide. | |
797 | */ | |
798 | ||
799 | static unsigned int count_free_highmem_pages(void) | |
800 | { | |
801 | struct zone *zone; | |
802 | unsigned int cnt = 0; | |
803 | ||
ee99c71c KM |
804 | for_each_populated_zone(zone) |
805 | if (is_highmem(zone)) | |
d23ad423 | 806 | cnt += zone_page_state(zone, NR_FREE_PAGES); |
8357376d RW |
807 | |
808 | return cnt; | |
809 | } | |
810 | ||
811 | /** | |
812 | * saveable_highmem_page - Determine whether a highmem page should be | |
813 | * included in the suspend image. | |
814 | * | |
815 | * We should save the page if it isn't Nosave or NosaveFree, or Reserved, | |
816 | * and it isn't a part of a free chunk of pages. | |
817 | */ | |
846705de | 818 | static struct page *saveable_highmem_page(struct zone *zone, unsigned long pfn) |
8357376d RW |
819 | { |
820 | struct page *page; | |
821 | ||
822 | if (!pfn_valid(pfn)) | |
823 | return NULL; | |
824 | ||
825 | page = pfn_to_page(pfn); | |
846705de RW |
826 | if (page_zone(page) != zone) |
827 | return NULL; | |
8357376d RW |
828 | |
829 | BUG_ON(!PageHighMem(page)); | |
830 | ||
7be98234 RW |
831 | if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page) || |
832 | PageReserved(page)) | |
8357376d RW |
833 | return NULL; |
834 | ||
835 | return page; | |
836 | } | |
837 | ||
838 | /** | |
839 | * count_highmem_pages - compute the total number of saveable highmem | |
840 | * pages. | |
841 | */ | |
842 | ||
843 | unsigned int count_highmem_pages(void) | |
844 | { | |
845 | struct zone *zone; | |
846 | unsigned int n = 0; | |
847 | ||
848 | for_each_zone(zone) { | |
849 | unsigned long pfn, max_zone_pfn; | |
850 | ||
851 | if (!is_highmem(zone)) | |
852 | continue; | |
853 | ||
854 | mark_free_pages(zone); | |
855 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; | |
856 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
846705de | 857 | if (saveable_highmem_page(zone, pfn)) |
8357376d RW |
858 | n++; |
859 | } | |
860 | return n; | |
861 | } | |
862 | #else | |
846705de RW |
863 | static inline void *saveable_highmem_page(struct zone *z, unsigned long p) |
864 | { | |
865 | return NULL; | |
866 | } | |
8357376d RW |
867 | #endif /* CONFIG_HIGHMEM */ |
868 | ||
25761b6e | 869 | /** |
8a235efa RW |
870 | * saveable_page - Determine whether a non-highmem page should be included |
871 | * in the suspend image. | |
25761b6e | 872 | * |
8357376d RW |
873 | * We should save the page if it isn't Nosave, and is not in the range |
874 | * of pages statically defined as 'unsaveable', and it isn't a part of | |
875 | * a free chunk of pages. | |
25761b6e | 876 | */ |
846705de | 877 | static struct page *saveable_page(struct zone *zone, unsigned long pfn) |
25761b6e | 878 | { |
de491861 | 879 | struct page *page; |
25761b6e RW |
880 | |
881 | if (!pfn_valid(pfn)) | |
ae83c5ee | 882 | return NULL; |
25761b6e RW |
883 | |
884 | page = pfn_to_page(pfn); | |
846705de RW |
885 | if (page_zone(page) != zone) |
886 | return NULL; | |
ae83c5ee | 887 | |
8357376d RW |
888 | BUG_ON(PageHighMem(page)); |
889 | ||
7be98234 | 890 | if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page)) |
ae83c5ee | 891 | return NULL; |
8357376d | 892 | |
8a235efa RW |
893 | if (PageReserved(page) |
894 | && (!kernel_page_present(page) || pfn_is_nosave(pfn))) | |
ae83c5ee | 895 | return NULL; |
25761b6e | 896 | |
ae83c5ee | 897 | return page; |
25761b6e RW |
898 | } |
899 | ||
8357376d RW |
900 | /** |
901 | * count_data_pages - compute the total number of saveable non-highmem | |
902 | * pages. | |
903 | */ | |
904 | ||
72a97e08 | 905 | unsigned int count_data_pages(void) |
25761b6e RW |
906 | { |
907 | struct zone *zone; | |
ae83c5ee | 908 | unsigned long pfn, max_zone_pfn; |
dc19d507 | 909 | unsigned int n = 0; |
25761b6e | 910 | |
8357376d | 911 | for_each_zone(zone) { |
25761b6e RW |
912 | if (is_highmem(zone)) |
913 | continue; | |
8357376d | 914 | |
25761b6e | 915 | mark_free_pages(zone); |
ae83c5ee RW |
916 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
917 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
846705de | 918 | if (saveable_page(zone, pfn)) |
8357376d | 919 | n++; |
25761b6e | 920 | } |
a0f49651 | 921 | return n; |
25761b6e RW |
922 | } |
923 | ||
8357376d RW |
924 | /* This is needed, because copy_page and memcpy are not usable for copying |
925 | * task structs. | |
926 | */ | |
927 | static inline void do_copy_page(long *dst, long *src) | |
f623f0db RW |
928 | { |
929 | int n; | |
930 | ||
f623f0db RW |
931 | for (n = PAGE_SIZE / sizeof(long); n; n--) |
932 | *dst++ = *src++; | |
933 | } | |
934 | ||
8a235efa RW |
935 | |
936 | /** | |
937 | * safe_copy_page - check if the page we are going to copy is marked as | |
938 | * present in the kernel page tables (this always is the case if | |
939 | * CONFIG_DEBUG_PAGEALLOC is not set and in that case | |
940 | * kernel_page_present() always returns 'true'). | |
941 | */ | |
942 | static void safe_copy_page(void *dst, struct page *s_page) | |
943 | { | |
944 | if (kernel_page_present(s_page)) { | |
945 | do_copy_page(dst, page_address(s_page)); | |
946 | } else { | |
947 | kernel_map_pages(s_page, 1, 1); | |
948 | do_copy_page(dst, page_address(s_page)); | |
949 | kernel_map_pages(s_page, 1, 0); | |
950 | } | |
951 | } | |
952 | ||
953 | ||
8357376d RW |
954 | #ifdef CONFIG_HIGHMEM |
955 | static inline struct page * | |
956 | page_is_saveable(struct zone *zone, unsigned long pfn) | |
957 | { | |
958 | return is_highmem(zone) ? | |
846705de | 959 | saveable_highmem_page(zone, pfn) : saveable_page(zone, pfn); |
8357376d RW |
960 | } |
961 | ||
8a235efa | 962 | static void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) |
8357376d RW |
963 | { |
964 | struct page *s_page, *d_page; | |
965 | void *src, *dst; | |
966 | ||
967 | s_page = pfn_to_page(src_pfn); | |
968 | d_page = pfn_to_page(dst_pfn); | |
969 | if (PageHighMem(s_page)) { | |
970 | src = kmap_atomic(s_page, KM_USER0); | |
971 | dst = kmap_atomic(d_page, KM_USER1); | |
972 | do_copy_page(dst, src); | |
973 | kunmap_atomic(src, KM_USER0); | |
974 | kunmap_atomic(dst, KM_USER1); | |
975 | } else { | |
8357376d RW |
976 | if (PageHighMem(d_page)) { |
977 | /* Page pointed to by src may contain some kernel | |
978 | * data modified by kmap_atomic() | |
979 | */ | |
8a235efa | 980 | safe_copy_page(buffer, s_page); |
baa5835d | 981 | dst = kmap_atomic(d_page, KM_USER0); |
8357376d RW |
982 | memcpy(dst, buffer, PAGE_SIZE); |
983 | kunmap_atomic(dst, KM_USER0); | |
984 | } else { | |
8a235efa | 985 | safe_copy_page(page_address(d_page), s_page); |
8357376d RW |
986 | } |
987 | } | |
988 | } | |
989 | #else | |
846705de | 990 | #define page_is_saveable(zone, pfn) saveable_page(zone, pfn) |
8357376d | 991 | |
8a235efa | 992 | static inline void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) |
8357376d | 993 | { |
8a235efa RW |
994 | safe_copy_page(page_address(pfn_to_page(dst_pfn)), |
995 | pfn_to_page(src_pfn)); | |
8357376d RW |
996 | } |
997 | #endif /* CONFIG_HIGHMEM */ | |
998 | ||
b788db79 RW |
999 | static void |
1000 | copy_data_pages(struct memory_bitmap *copy_bm, struct memory_bitmap *orig_bm) | |
25761b6e RW |
1001 | { |
1002 | struct zone *zone; | |
b788db79 | 1003 | unsigned long pfn; |
25761b6e | 1004 | |
8357376d | 1005 | for_each_zone(zone) { |
b788db79 RW |
1006 | unsigned long max_zone_pfn; |
1007 | ||
25761b6e | 1008 | mark_free_pages(zone); |
ae83c5ee | 1009 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
b788db79 | 1010 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) |
8357376d | 1011 | if (page_is_saveable(zone, pfn)) |
b788db79 | 1012 | memory_bm_set_bit(orig_bm, pfn); |
25761b6e | 1013 | } |
b788db79 RW |
1014 | memory_bm_position_reset(orig_bm); |
1015 | memory_bm_position_reset(copy_bm); | |
df7c4872 | 1016 | for(;;) { |
b788db79 | 1017 | pfn = memory_bm_next_pfn(orig_bm); |
df7c4872 FW |
1018 | if (unlikely(pfn == BM_END_OF_MAP)) |
1019 | break; | |
1020 | copy_data_page(memory_bm_next_pfn(copy_bm), pfn); | |
1021 | } | |
25761b6e RW |
1022 | } |
1023 | ||
8357376d RW |
1024 | /* Total number of image pages */ |
1025 | static unsigned int nr_copy_pages; | |
1026 | /* Number of pages needed for saving the original pfns of the image pages */ | |
1027 | static unsigned int nr_meta_pages; | |
1028 | ||
25761b6e | 1029 | /** |
940864dd | 1030 | * swsusp_free - free pages allocated for the suspend. |
cd560bb2 | 1031 | * |
940864dd RW |
1032 | * Suspend pages are alocated before the atomic copy is made, so we |
1033 | * need to release them after the resume. | |
25761b6e RW |
1034 | */ |
1035 | ||
1036 | void swsusp_free(void) | |
1037 | { | |
1038 | struct zone *zone; | |
ae83c5ee | 1039 | unsigned long pfn, max_zone_pfn; |
25761b6e RW |
1040 | |
1041 | for_each_zone(zone) { | |
ae83c5ee RW |
1042 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
1043 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
1044 | if (pfn_valid(pfn)) { | |
1045 | struct page *page = pfn_to_page(pfn); | |
1046 | ||
7be98234 RW |
1047 | if (swsusp_page_is_forbidden(page) && |
1048 | swsusp_page_is_free(page)) { | |
1049 | swsusp_unset_page_forbidden(page); | |
1050 | swsusp_unset_page_free(page); | |
8357376d | 1051 | __free_page(page); |
25761b6e RW |
1052 | } |
1053 | } | |
1054 | } | |
f577eb30 RW |
1055 | nr_copy_pages = 0; |
1056 | nr_meta_pages = 0; | |
75534b50 | 1057 | restore_pblist = NULL; |
6e1819d6 | 1058 | buffer = NULL; |
25761b6e RW |
1059 | } |
1060 | ||
8357376d RW |
1061 | #ifdef CONFIG_HIGHMEM |
1062 | /** | |
1063 | * count_pages_for_highmem - compute the number of non-highmem pages | |
1064 | * that will be necessary for creating copies of highmem pages. | |
1065 | */ | |
1066 | ||
1067 | static unsigned int count_pages_for_highmem(unsigned int nr_highmem) | |
1068 | { | |
1069 | unsigned int free_highmem = count_free_highmem_pages(); | |
1070 | ||
1071 | if (free_highmem >= nr_highmem) | |
1072 | nr_highmem = 0; | |
1073 | else | |
1074 | nr_highmem -= free_highmem; | |
1075 | ||
1076 | return nr_highmem; | |
1077 | } | |
1078 | #else | |
1079 | static unsigned int | |
1080 | count_pages_for_highmem(unsigned int nr_highmem) { return 0; } | |
1081 | #endif /* CONFIG_HIGHMEM */ | |
25761b6e RW |
1082 | |
1083 | /** | |
8357376d RW |
1084 | * enough_free_mem - Make sure we have enough free memory for the |
1085 | * snapshot image. | |
25761b6e RW |
1086 | */ |
1087 | ||
8357376d | 1088 | static int enough_free_mem(unsigned int nr_pages, unsigned int nr_highmem) |
25761b6e | 1089 | { |
e5e2fa78 | 1090 | struct zone *zone; |
940864dd | 1091 | unsigned int free = 0, meta = 0; |
e5e2fa78 | 1092 | |
8357376d RW |
1093 | for_each_zone(zone) { |
1094 | meta += snapshot_additional_pages(zone); | |
1095 | if (!is_highmem(zone)) | |
d23ad423 | 1096 | free += zone_page_state(zone, NR_FREE_PAGES); |
8357376d | 1097 | } |
940864dd | 1098 | |
8357376d | 1099 | nr_pages += count_pages_for_highmem(nr_highmem); |
23976728 | 1100 | pr_debug("PM: Normal pages needed: %u + %u + %u, available pages: %u\n", |
940864dd RW |
1101 | nr_pages, PAGES_FOR_IO, meta, free); |
1102 | ||
1103 | return free > nr_pages + PAGES_FOR_IO + meta; | |
25761b6e RW |
1104 | } |
1105 | ||
8357376d RW |
1106 | #ifdef CONFIG_HIGHMEM |
1107 | /** | |
1108 | * get_highmem_buffer - if there are some highmem pages in the suspend | |
1109 | * image, we may need the buffer to copy them and/or load their data. | |
1110 | */ | |
1111 | ||
1112 | static inline int get_highmem_buffer(int safe_needed) | |
1113 | { | |
1114 | buffer = get_image_page(GFP_ATOMIC | __GFP_COLD, safe_needed); | |
1115 | return buffer ? 0 : -ENOMEM; | |
1116 | } | |
1117 | ||
1118 | /** | |
1119 | * alloc_highmem_image_pages - allocate some highmem pages for the image. | |
1120 | * Try to allocate as many pages as needed, but if the number of free | |
1121 | * highmem pages is lesser than that, allocate them all. | |
1122 | */ | |
1123 | ||
1124 | static inline unsigned int | |
1125 | alloc_highmem_image_pages(struct memory_bitmap *bm, unsigned int nr_highmem) | |
1126 | { | |
1127 | unsigned int to_alloc = count_free_highmem_pages(); | |
1128 | ||
1129 | if (to_alloc > nr_highmem) | |
1130 | to_alloc = nr_highmem; | |
1131 | ||
1132 | nr_highmem -= to_alloc; | |
1133 | while (to_alloc-- > 0) { | |
1134 | struct page *page; | |
1135 | ||
1136 | page = alloc_image_page(__GFP_HIGHMEM); | |
1137 | memory_bm_set_bit(bm, page_to_pfn(page)); | |
1138 | } | |
1139 | return nr_highmem; | |
1140 | } | |
1141 | #else | |
1142 | static inline int get_highmem_buffer(int safe_needed) { return 0; } | |
1143 | ||
1144 | static inline unsigned int | |
1145 | alloc_highmem_image_pages(struct memory_bitmap *bm, unsigned int n) { return 0; } | |
1146 | #endif /* CONFIG_HIGHMEM */ | |
1147 | ||
1148 | /** | |
1149 | * swsusp_alloc - allocate memory for the suspend image | |
1150 | * | |
1151 | * We first try to allocate as many highmem pages as there are | |
1152 | * saveable highmem pages in the system. If that fails, we allocate | |
1153 | * non-highmem pages for the copies of the remaining highmem ones. | |
1154 | * | |
1155 | * In this approach it is likely that the copies of highmem pages will | |
1156 | * also be located in the high memory, because of the way in which | |
1157 | * copy_data_pages() works. | |
1158 | */ | |
1159 | ||
b788db79 RW |
1160 | static int |
1161 | swsusp_alloc(struct memory_bitmap *orig_bm, struct memory_bitmap *copy_bm, | |
8357376d | 1162 | unsigned int nr_pages, unsigned int nr_highmem) |
054bd4c1 | 1163 | { |
b788db79 | 1164 | int error; |
054bd4c1 | 1165 | |
b788db79 RW |
1166 | error = memory_bm_create(orig_bm, GFP_ATOMIC | __GFP_COLD, PG_ANY); |
1167 | if (error) | |
1168 | goto Free; | |
25761b6e | 1169 | |
b788db79 RW |
1170 | error = memory_bm_create(copy_bm, GFP_ATOMIC | __GFP_COLD, PG_ANY); |
1171 | if (error) | |
1172 | goto Free; | |
25761b6e | 1173 | |
8357376d RW |
1174 | if (nr_highmem > 0) { |
1175 | error = get_highmem_buffer(PG_ANY); | |
1176 | if (error) | |
1177 | goto Free; | |
1178 | ||
1179 | nr_pages += alloc_highmem_image_pages(copy_bm, nr_highmem); | |
1180 | } | |
b788db79 | 1181 | while (nr_pages-- > 0) { |
8357376d RW |
1182 | struct page *page = alloc_image_page(GFP_ATOMIC | __GFP_COLD); |
1183 | ||
b788db79 RW |
1184 | if (!page) |
1185 | goto Free; | |
25761b6e | 1186 | |
b788db79 | 1187 | memory_bm_set_bit(copy_bm, page_to_pfn(page)); |
25761b6e | 1188 | } |
b788db79 | 1189 | return 0; |
25761b6e | 1190 | |
59a49335 | 1191 | Free: |
b788db79 RW |
1192 | swsusp_free(); |
1193 | return -ENOMEM; | |
25761b6e RW |
1194 | } |
1195 | ||
8357376d RW |
1196 | /* Memory bitmap used for marking saveable pages (during suspend) or the |
1197 | * suspend image pages (during resume) | |
1198 | */ | |
b788db79 | 1199 | static struct memory_bitmap orig_bm; |
8357376d RW |
1200 | /* Memory bitmap used on suspend for marking allocated pages that will contain |
1201 | * the copies of saveable pages. During resume it is initially used for | |
1202 | * marking the suspend image pages, but then its set bits are duplicated in | |
1203 | * @orig_bm and it is released. Next, on systems with high memory, it may be | |
1204 | * used for marking "safe" highmem pages, but it has to be reinitialized for | |
1205 | * this purpose. | |
b788db79 RW |
1206 | */ |
1207 | static struct memory_bitmap copy_bm; | |
1208 | ||
2e32a43e | 1209 | asmlinkage int swsusp_save(void) |
25761b6e | 1210 | { |
8357376d | 1211 | unsigned int nr_pages, nr_highmem; |
25761b6e | 1212 | |
23976728 | 1213 | printk(KERN_INFO "PM: Creating hibernation image: \n"); |
25761b6e | 1214 | |
9f8f2172 | 1215 | drain_local_pages(NULL); |
a0f49651 | 1216 | nr_pages = count_data_pages(); |
8357376d | 1217 | nr_highmem = count_highmem_pages(); |
23976728 | 1218 | printk(KERN_INFO "PM: Need to copy %u pages\n", nr_pages + nr_highmem); |
25761b6e | 1219 | |
8357376d | 1220 | if (!enough_free_mem(nr_pages, nr_highmem)) { |
23976728 | 1221 | printk(KERN_ERR "PM: Not enough free memory\n"); |
25761b6e RW |
1222 | return -ENOMEM; |
1223 | } | |
1224 | ||
8357376d | 1225 | if (swsusp_alloc(&orig_bm, ©_bm, nr_pages, nr_highmem)) { |
23976728 | 1226 | printk(KERN_ERR "PM: Memory allocation failed\n"); |
a0f49651 | 1227 | return -ENOMEM; |
8357376d | 1228 | } |
25761b6e RW |
1229 | |
1230 | /* During allocating of suspend pagedir, new cold pages may appear. | |
1231 | * Kill them. | |
1232 | */ | |
9f8f2172 | 1233 | drain_local_pages(NULL); |
b788db79 | 1234 | copy_data_pages(©_bm, &orig_bm); |
25761b6e RW |
1235 | |
1236 | /* | |
1237 | * End of critical section. From now on, we can write to memory, | |
1238 | * but we should not touch disk. This specially means we must _not_ | |
1239 | * touch swap space! Except we must write out our image of course. | |
1240 | */ | |
1241 | ||
8357376d | 1242 | nr_pages += nr_highmem; |
a0f49651 | 1243 | nr_copy_pages = nr_pages; |
8357376d | 1244 | nr_meta_pages = DIV_ROUND_UP(nr_pages * sizeof(long), PAGE_SIZE); |
a0f49651 | 1245 | |
23976728 RW |
1246 | printk(KERN_INFO "PM: Hibernation image created (%d pages copied)\n", |
1247 | nr_pages); | |
8357376d | 1248 | |
25761b6e RW |
1249 | return 0; |
1250 | } | |
f577eb30 | 1251 | |
d307c4a8 RW |
1252 | #ifndef CONFIG_ARCH_HIBERNATION_HEADER |
1253 | static int init_header_complete(struct swsusp_info *info) | |
f577eb30 | 1254 | { |
d307c4a8 | 1255 | memcpy(&info->uts, init_utsname(), sizeof(struct new_utsname)); |
f577eb30 | 1256 | info->version_code = LINUX_VERSION_CODE; |
d307c4a8 RW |
1257 | return 0; |
1258 | } | |
1259 | ||
1260 | static char *check_image_kernel(struct swsusp_info *info) | |
1261 | { | |
1262 | if (info->version_code != LINUX_VERSION_CODE) | |
1263 | return "kernel version"; | |
1264 | if (strcmp(info->uts.sysname,init_utsname()->sysname)) | |
1265 | return "system type"; | |
1266 | if (strcmp(info->uts.release,init_utsname()->release)) | |
1267 | return "kernel release"; | |
1268 | if (strcmp(info->uts.version,init_utsname()->version)) | |
1269 | return "version"; | |
1270 | if (strcmp(info->uts.machine,init_utsname()->machine)) | |
1271 | return "machine"; | |
1272 | return NULL; | |
1273 | } | |
1274 | #endif /* CONFIG_ARCH_HIBERNATION_HEADER */ | |
1275 | ||
af508b34 RW |
1276 | unsigned long snapshot_get_image_size(void) |
1277 | { | |
1278 | return nr_copy_pages + nr_meta_pages + 1; | |
1279 | } | |
1280 | ||
d307c4a8 RW |
1281 | static int init_header(struct swsusp_info *info) |
1282 | { | |
1283 | memset(info, 0, sizeof(struct swsusp_info)); | |
f577eb30 | 1284 | info->num_physpages = num_physpages; |
f577eb30 | 1285 | info->image_pages = nr_copy_pages; |
af508b34 | 1286 | info->pages = snapshot_get_image_size(); |
6e1819d6 RW |
1287 | info->size = info->pages; |
1288 | info->size <<= PAGE_SHIFT; | |
d307c4a8 | 1289 | return init_header_complete(info); |
f577eb30 RW |
1290 | } |
1291 | ||
1292 | /** | |
940864dd RW |
1293 | * pack_pfns - pfns corresponding to the set bits found in the bitmap @bm |
1294 | * are stored in the array @buf[] (1 page at a time) | |
f577eb30 RW |
1295 | */ |
1296 | ||
b788db79 | 1297 | static inline void |
940864dd | 1298 | pack_pfns(unsigned long *buf, struct memory_bitmap *bm) |
f577eb30 RW |
1299 | { |
1300 | int j; | |
1301 | ||
b788db79 | 1302 | for (j = 0; j < PAGE_SIZE / sizeof(long); j++) { |
940864dd RW |
1303 | buf[j] = memory_bm_next_pfn(bm); |
1304 | if (unlikely(buf[j] == BM_END_OF_MAP)) | |
b788db79 | 1305 | break; |
f577eb30 | 1306 | } |
f577eb30 RW |
1307 | } |
1308 | ||
1309 | /** | |
1310 | * snapshot_read_next - used for reading the system memory snapshot. | |
1311 | * | |
1312 | * On the first call to it @handle should point to a zeroed | |
1313 | * snapshot_handle structure. The structure gets updated and a pointer | |
1314 | * to it should be passed to this function every next time. | |
1315 | * | |
1316 | * The @count parameter should contain the number of bytes the caller | |
1317 | * wants to read from the snapshot. It must not be zero. | |
1318 | * | |
1319 | * On success the function returns a positive number. Then, the caller | |
1320 | * is allowed to read up to the returned number of bytes from the memory | |
1321 | * location computed by the data_of() macro. The number returned | |
1322 | * may be smaller than @count, but this only happens if the read would | |
1323 | * cross a page boundary otherwise. | |
1324 | * | |
1325 | * The function returns 0 to indicate the end of data stream condition, | |
1326 | * and a negative number is returned on error. In such cases the | |
1327 | * structure pointed to by @handle is not updated and should not be used | |
1328 | * any more. | |
1329 | */ | |
1330 | ||
1331 | int snapshot_read_next(struct snapshot_handle *handle, size_t count) | |
1332 | { | |
fb13a28b | 1333 | if (handle->cur > nr_meta_pages + nr_copy_pages) |
f577eb30 | 1334 | return 0; |
b788db79 | 1335 | |
f577eb30 RW |
1336 | if (!buffer) { |
1337 | /* This makes the buffer be freed by swsusp_free() */ | |
8357376d | 1338 | buffer = get_image_page(GFP_ATOMIC, PG_ANY); |
f577eb30 RW |
1339 | if (!buffer) |
1340 | return -ENOMEM; | |
1341 | } | |
1342 | if (!handle->offset) { | |
d307c4a8 RW |
1343 | int error; |
1344 | ||
1345 | error = init_header((struct swsusp_info *)buffer); | |
1346 | if (error) | |
1347 | return error; | |
f577eb30 | 1348 | handle->buffer = buffer; |
b788db79 RW |
1349 | memory_bm_position_reset(&orig_bm); |
1350 | memory_bm_position_reset(©_bm); | |
f577eb30 | 1351 | } |
fb13a28b RW |
1352 | if (handle->prev < handle->cur) { |
1353 | if (handle->cur <= nr_meta_pages) { | |
b788db79 | 1354 | memset(buffer, 0, PAGE_SIZE); |
940864dd | 1355 | pack_pfns(buffer, &orig_bm); |
f577eb30 | 1356 | } else { |
8357376d | 1357 | struct page *page; |
b788db79 | 1358 | |
8357376d RW |
1359 | page = pfn_to_page(memory_bm_next_pfn(©_bm)); |
1360 | if (PageHighMem(page)) { | |
1361 | /* Highmem pages are copied to the buffer, | |
1362 | * because we can't return with a kmapped | |
1363 | * highmem page (we may not be called again). | |
1364 | */ | |
1365 | void *kaddr; | |
1366 | ||
1367 | kaddr = kmap_atomic(page, KM_USER0); | |
1368 | memcpy(buffer, kaddr, PAGE_SIZE); | |
1369 | kunmap_atomic(kaddr, KM_USER0); | |
1370 | handle->buffer = buffer; | |
1371 | } else { | |
1372 | handle->buffer = page_address(page); | |
1373 | } | |
f577eb30 | 1374 | } |
fb13a28b | 1375 | handle->prev = handle->cur; |
f577eb30 | 1376 | } |
fb13a28b RW |
1377 | handle->buf_offset = handle->cur_offset; |
1378 | if (handle->cur_offset + count >= PAGE_SIZE) { | |
1379 | count = PAGE_SIZE - handle->cur_offset; | |
1380 | handle->cur_offset = 0; | |
1381 | handle->cur++; | |
f577eb30 | 1382 | } else { |
fb13a28b | 1383 | handle->cur_offset += count; |
f577eb30 RW |
1384 | } |
1385 | handle->offset += count; | |
1386 | return count; | |
1387 | } | |
1388 | ||
1389 | /** | |
1390 | * mark_unsafe_pages - mark the pages that cannot be used for storing | |
1391 | * the image during resume, because they conflict with the pages that | |
1392 | * had been used before suspend | |
1393 | */ | |
1394 | ||
940864dd | 1395 | static int mark_unsafe_pages(struct memory_bitmap *bm) |
f577eb30 RW |
1396 | { |
1397 | struct zone *zone; | |
ae83c5ee | 1398 | unsigned long pfn, max_zone_pfn; |
f577eb30 RW |
1399 | |
1400 | /* Clear page flags */ | |
8357376d | 1401 | for_each_zone(zone) { |
ae83c5ee RW |
1402 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
1403 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
1404 | if (pfn_valid(pfn)) | |
7be98234 | 1405 | swsusp_unset_page_free(pfn_to_page(pfn)); |
f577eb30 RW |
1406 | } |
1407 | ||
940864dd RW |
1408 | /* Mark pages that correspond to the "original" pfns as "unsafe" */ |
1409 | memory_bm_position_reset(bm); | |
1410 | do { | |
1411 | pfn = memory_bm_next_pfn(bm); | |
1412 | if (likely(pfn != BM_END_OF_MAP)) { | |
1413 | if (likely(pfn_valid(pfn))) | |
7be98234 | 1414 | swsusp_set_page_free(pfn_to_page(pfn)); |
940864dd RW |
1415 | else |
1416 | return -EFAULT; | |
1417 | } | |
1418 | } while (pfn != BM_END_OF_MAP); | |
f577eb30 | 1419 | |
940864dd | 1420 | allocated_unsafe_pages = 0; |
968808b8 | 1421 | |
f577eb30 RW |
1422 | return 0; |
1423 | } | |
1424 | ||
940864dd RW |
1425 | static void |
1426 | duplicate_memory_bitmap(struct memory_bitmap *dst, struct memory_bitmap *src) | |
f577eb30 | 1427 | { |
940864dd RW |
1428 | unsigned long pfn; |
1429 | ||
1430 | memory_bm_position_reset(src); | |
1431 | pfn = memory_bm_next_pfn(src); | |
1432 | while (pfn != BM_END_OF_MAP) { | |
1433 | memory_bm_set_bit(dst, pfn); | |
1434 | pfn = memory_bm_next_pfn(src); | |
f577eb30 RW |
1435 | } |
1436 | } | |
1437 | ||
d307c4a8 | 1438 | static int check_header(struct swsusp_info *info) |
f577eb30 | 1439 | { |
d307c4a8 | 1440 | char *reason; |
f577eb30 | 1441 | |
d307c4a8 RW |
1442 | reason = check_image_kernel(info); |
1443 | if (!reason && info->num_physpages != num_physpages) | |
f577eb30 | 1444 | reason = "memory size"; |
f577eb30 | 1445 | if (reason) { |
23976728 | 1446 | printk(KERN_ERR "PM: Image mismatch: %s\n", reason); |
f577eb30 RW |
1447 | return -EPERM; |
1448 | } | |
1449 | return 0; | |
1450 | } | |
1451 | ||
1452 | /** | |
1453 | * load header - check the image header and copy data from it | |
1454 | */ | |
1455 | ||
940864dd RW |
1456 | static int |
1457 | load_header(struct swsusp_info *info) | |
f577eb30 RW |
1458 | { |
1459 | int error; | |
f577eb30 | 1460 | |
940864dd | 1461 | restore_pblist = NULL; |
f577eb30 RW |
1462 | error = check_header(info); |
1463 | if (!error) { | |
f577eb30 RW |
1464 | nr_copy_pages = info->image_pages; |
1465 | nr_meta_pages = info->pages - info->image_pages - 1; | |
1466 | } | |
1467 | return error; | |
1468 | } | |
1469 | ||
1470 | /** | |
940864dd RW |
1471 | * unpack_orig_pfns - for each element of @buf[] (1 page at a time) set |
1472 | * the corresponding bit in the memory bitmap @bm | |
f577eb30 | 1473 | */ |
69643279 | 1474 | static int unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm) |
f577eb30 RW |
1475 | { |
1476 | int j; | |
1477 | ||
940864dd RW |
1478 | for (j = 0; j < PAGE_SIZE / sizeof(long); j++) { |
1479 | if (unlikely(buf[j] == BM_END_OF_MAP)) | |
1480 | break; | |
1481 | ||
69643279 RW |
1482 | if (memory_bm_pfn_present(bm, buf[j])) |
1483 | memory_bm_set_bit(bm, buf[j]); | |
1484 | else | |
1485 | return -EFAULT; | |
f577eb30 | 1486 | } |
69643279 RW |
1487 | |
1488 | return 0; | |
f577eb30 RW |
1489 | } |
1490 | ||
8357376d RW |
1491 | /* List of "safe" pages that may be used to store data loaded from the suspend |
1492 | * image | |
1493 | */ | |
1494 | static struct linked_page *safe_pages_list; | |
1495 | ||
1496 | #ifdef CONFIG_HIGHMEM | |
1497 | /* struct highmem_pbe is used for creating the list of highmem pages that | |
1498 | * should be restored atomically during the resume from disk, because the page | |
1499 | * frames they have occupied before the suspend are in use. | |
1500 | */ | |
1501 | struct highmem_pbe { | |
1502 | struct page *copy_page; /* data is here now */ | |
1503 | struct page *orig_page; /* data was here before the suspend */ | |
1504 | struct highmem_pbe *next; | |
1505 | }; | |
1506 | ||
1507 | /* List of highmem PBEs needed for restoring the highmem pages that were | |
1508 | * allocated before the suspend and included in the suspend image, but have | |
1509 | * also been allocated by the "resume" kernel, so their contents cannot be | |
1510 | * written directly to their "original" page frames. | |
1511 | */ | |
1512 | static struct highmem_pbe *highmem_pblist; | |
1513 | ||
1514 | /** | |
1515 | * count_highmem_image_pages - compute the number of highmem pages in the | |
1516 | * suspend image. The bits in the memory bitmap @bm that correspond to the | |
1517 | * image pages are assumed to be set. | |
1518 | */ | |
1519 | ||
1520 | static unsigned int count_highmem_image_pages(struct memory_bitmap *bm) | |
1521 | { | |
1522 | unsigned long pfn; | |
1523 | unsigned int cnt = 0; | |
1524 | ||
1525 | memory_bm_position_reset(bm); | |
1526 | pfn = memory_bm_next_pfn(bm); | |
1527 | while (pfn != BM_END_OF_MAP) { | |
1528 | if (PageHighMem(pfn_to_page(pfn))) | |
1529 | cnt++; | |
1530 | ||
1531 | pfn = memory_bm_next_pfn(bm); | |
1532 | } | |
1533 | return cnt; | |
1534 | } | |
1535 | ||
1536 | /** | |
1537 | * prepare_highmem_image - try to allocate as many highmem pages as | |
1538 | * there are highmem image pages (@nr_highmem_p points to the variable | |
1539 | * containing the number of highmem image pages). The pages that are | |
1540 | * "safe" (ie. will not be overwritten when the suspend image is | |
1541 | * restored) have the corresponding bits set in @bm (it must be | |
1542 | * unitialized). | |
1543 | * | |
1544 | * NOTE: This function should not be called if there are no highmem | |
1545 | * image pages. | |
1546 | */ | |
1547 | ||
1548 | static unsigned int safe_highmem_pages; | |
1549 | ||
1550 | static struct memory_bitmap *safe_highmem_bm; | |
1551 | ||
1552 | static int | |
1553 | prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p) | |
1554 | { | |
1555 | unsigned int to_alloc; | |
1556 | ||
1557 | if (memory_bm_create(bm, GFP_ATOMIC, PG_SAFE)) | |
1558 | return -ENOMEM; | |
1559 | ||
1560 | if (get_highmem_buffer(PG_SAFE)) | |
1561 | return -ENOMEM; | |
1562 | ||
1563 | to_alloc = count_free_highmem_pages(); | |
1564 | if (to_alloc > *nr_highmem_p) | |
1565 | to_alloc = *nr_highmem_p; | |
1566 | else | |
1567 | *nr_highmem_p = to_alloc; | |
1568 | ||
1569 | safe_highmem_pages = 0; | |
1570 | while (to_alloc-- > 0) { | |
1571 | struct page *page; | |
1572 | ||
1573 | page = alloc_page(__GFP_HIGHMEM); | |
7be98234 | 1574 | if (!swsusp_page_is_free(page)) { |
8357376d RW |
1575 | /* The page is "safe", set its bit the bitmap */ |
1576 | memory_bm_set_bit(bm, page_to_pfn(page)); | |
1577 | safe_highmem_pages++; | |
1578 | } | |
1579 | /* Mark the page as allocated */ | |
7be98234 RW |
1580 | swsusp_set_page_forbidden(page); |
1581 | swsusp_set_page_free(page); | |
8357376d RW |
1582 | } |
1583 | memory_bm_position_reset(bm); | |
1584 | safe_highmem_bm = bm; | |
1585 | return 0; | |
1586 | } | |
1587 | ||
1588 | /** | |
1589 | * get_highmem_page_buffer - for given highmem image page find the buffer | |
1590 | * that suspend_write_next() should set for its caller to write to. | |
1591 | * | |
1592 | * If the page is to be saved to its "original" page frame or a copy of | |
1593 | * the page is to be made in the highmem, @buffer is returned. Otherwise, | |
1594 | * the copy of the page is to be made in normal memory, so the address of | |
1595 | * the copy is returned. | |
1596 | * | |
1597 | * If @buffer is returned, the caller of suspend_write_next() will write | |
1598 | * the page's contents to @buffer, so they will have to be copied to the | |
1599 | * right location on the next call to suspend_write_next() and it is done | |
1600 | * with the help of copy_last_highmem_page(). For this purpose, if | |
1601 | * @buffer is returned, @last_highmem page is set to the page to which | |
1602 | * the data will have to be copied from @buffer. | |
1603 | */ | |
1604 | ||
1605 | static struct page *last_highmem_page; | |
1606 | ||
1607 | static void * | |
1608 | get_highmem_page_buffer(struct page *page, struct chain_allocator *ca) | |
1609 | { | |
1610 | struct highmem_pbe *pbe; | |
1611 | void *kaddr; | |
1612 | ||
7be98234 | 1613 | if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page)) { |
8357376d RW |
1614 | /* We have allocated the "original" page frame and we can |
1615 | * use it directly to store the loaded page. | |
1616 | */ | |
1617 | last_highmem_page = page; | |
1618 | return buffer; | |
1619 | } | |
1620 | /* The "original" page frame has not been allocated and we have to | |
1621 | * use a "safe" page frame to store the loaded page. | |
1622 | */ | |
1623 | pbe = chain_alloc(ca, sizeof(struct highmem_pbe)); | |
1624 | if (!pbe) { | |
1625 | swsusp_free(); | |
69643279 | 1626 | return ERR_PTR(-ENOMEM); |
8357376d RW |
1627 | } |
1628 | pbe->orig_page = page; | |
1629 | if (safe_highmem_pages > 0) { | |
1630 | struct page *tmp; | |
1631 | ||
1632 | /* Copy of the page will be stored in high memory */ | |
1633 | kaddr = buffer; | |
1634 | tmp = pfn_to_page(memory_bm_next_pfn(safe_highmem_bm)); | |
1635 | safe_highmem_pages--; | |
1636 | last_highmem_page = tmp; | |
1637 | pbe->copy_page = tmp; | |
1638 | } else { | |
1639 | /* Copy of the page will be stored in normal memory */ | |
1640 | kaddr = safe_pages_list; | |
1641 | safe_pages_list = safe_pages_list->next; | |
1642 | pbe->copy_page = virt_to_page(kaddr); | |
1643 | } | |
1644 | pbe->next = highmem_pblist; | |
1645 | highmem_pblist = pbe; | |
1646 | return kaddr; | |
1647 | } | |
1648 | ||
1649 | /** | |
1650 | * copy_last_highmem_page - copy the contents of a highmem image from | |
1651 | * @buffer, where the caller of snapshot_write_next() has place them, | |
1652 | * to the right location represented by @last_highmem_page . | |
1653 | */ | |
1654 | ||
1655 | static void copy_last_highmem_page(void) | |
1656 | { | |
1657 | if (last_highmem_page) { | |
1658 | void *dst; | |
1659 | ||
1660 | dst = kmap_atomic(last_highmem_page, KM_USER0); | |
1661 | memcpy(dst, buffer, PAGE_SIZE); | |
1662 | kunmap_atomic(dst, KM_USER0); | |
1663 | last_highmem_page = NULL; | |
1664 | } | |
1665 | } | |
1666 | ||
1667 | static inline int last_highmem_page_copied(void) | |
1668 | { | |
1669 | return !last_highmem_page; | |
1670 | } | |
1671 | ||
1672 | static inline void free_highmem_data(void) | |
1673 | { | |
1674 | if (safe_highmem_bm) | |
1675 | memory_bm_free(safe_highmem_bm, PG_UNSAFE_CLEAR); | |
1676 | ||
1677 | if (buffer) | |
1678 | free_image_page(buffer, PG_UNSAFE_CLEAR); | |
1679 | } | |
1680 | #else | |
1681 | static inline int get_safe_write_buffer(void) { return 0; } | |
1682 | ||
1683 | static unsigned int | |
1684 | count_highmem_image_pages(struct memory_bitmap *bm) { return 0; } | |
1685 | ||
1686 | static inline int | |
1687 | prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p) | |
1688 | { | |
1689 | return 0; | |
1690 | } | |
1691 | ||
1692 | static inline void * | |
1693 | get_highmem_page_buffer(struct page *page, struct chain_allocator *ca) | |
1694 | { | |
69643279 | 1695 | return ERR_PTR(-EINVAL); |
8357376d RW |
1696 | } |
1697 | ||
1698 | static inline void copy_last_highmem_page(void) {} | |
1699 | static inline int last_highmem_page_copied(void) { return 1; } | |
1700 | static inline void free_highmem_data(void) {} | |
1701 | #endif /* CONFIG_HIGHMEM */ | |
1702 | ||
f577eb30 | 1703 | /** |
940864dd RW |
1704 | * prepare_image - use the memory bitmap @bm to mark the pages that will |
1705 | * be overwritten in the process of restoring the system memory state | |
1706 | * from the suspend image ("unsafe" pages) and allocate memory for the | |
1707 | * image. | |
968808b8 | 1708 | * |
940864dd RW |
1709 | * The idea is to allocate a new memory bitmap first and then allocate |
1710 | * as many pages as needed for the image data, but not to assign these | |
1711 | * pages to specific tasks initially. Instead, we just mark them as | |
8357376d RW |
1712 | * allocated and create a lists of "safe" pages that will be used |
1713 | * later. On systems with high memory a list of "safe" highmem pages is | |
1714 | * also created. | |
f577eb30 RW |
1715 | */ |
1716 | ||
940864dd RW |
1717 | #define PBES_PER_LINKED_PAGE (LINKED_PAGE_DATA_SIZE / sizeof(struct pbe)) |
1718 | ||
940864dd RW |
1719 | static int |
1720 | prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm) | |
f577eb30 | 1721 | { |
8357376d | 1722 | unsigned int nr_pages, nr_highmem; |
940864dd RW |
1723 | struct linked_page *sp_list, *lp; |
1724 | int error; | |
f577eb30 | 1725 | |
8357376d RW |
1726 | /* If there is no highmem, the buffer will not be necessary */ |
1727 | free_image_page(buffer, PG_UNSAFE_CLEAR); | |
1728 | buffer = NULL; | |
1729 | ||
1730 | nr_highmem = count_highmem_image_pages(bm); | |
940864dd RW |
1731 | error = mark_unsafe_pages(bm); |
1732 | if (error) | |
1733 | goto Free; | |
1734 | ||
1735 | error = memory_bm_create(new_bm, GFP_ATOMIC, PG_SAFE); | |
1736 | if (error) | |
1737 | goto Free; | |
1738 | ||
1739 | duplicate_memory_bitmap(new_bm, bm); | |
1740 | memory_bm_free(bm, PG_UNSAFE_KEEP); | |
8357376d RW |
1741 | if (nr_highmem > 0) { |
1742 | error = prepare_highmem_image(bm, &nr_highmem); | |
1743 | if (error) | |
1744 | goto Free; | |
1745 | } | |
940864dd RW |
1746 | /* Reserve some safe pages for potential later use. |
1747 | * | |
1748 | * NOTE: This way we make sure there will be enough safe pages for the | |
1749 | * chain_alloc() in get_buffer(). It is a bit wasteful, but | |
1750 | * nr_copy_pages cannot be greater than 50% of the memory anyway. | |
1751 | */ | |
1752 | sp_list = NULL; | |
1753 | /* nr_copy_pages cannot be lesser than allocated_unsafe_pages */ | |
8357376d | 1754 | nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages; |
940864dd RW |
1755 | nr_pages = DIV_ROUND_UP(nr_pages, PBES_PER_LINKED_PAGE); |
1756 | while (nr_pages > 0) { | |
8357376d | 1757 | lp = get_image_page(GFP_ATOMIC, PG_SAFE); |
940864dd | 1758 | if (!lp) { |
f577eb30 | 1759 | error = -ENOMEM; |
940864dd RW |
1760 | goto Free; |
1761 | } | |
1762 | lp->next = sp_list; | |
1763 | sp_list = lp; | |
1764 | nr_pages--; | |
f577eb30 | 1765 | } |
940864dd RW |
1766 | /* Preallocate memory for the image */ |
1767 | safe_pages_list = NULL; | |
8357376d | 1768 | nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages; |
940864dd RW |
1769 | while (nr_pages > 0) { |
1770 | lp = (struct linked_page *)get_zeroed_page(GFP_ATOMIC); | |
1771 | if (!lp) { | |
1772 | error = -ENOMEM; | |
1773 | goto Free; | |
1774 | } | |
7be98234 | 1775 | if (!swsusp_page_is_free(virt_to_page(lp))) { |
940864dd RW |
1776 | /* The page is "safe", add it to the list */ |
1777 | lp->next = safe_pages_list; | |
1778 | safe_pages_list = lp; | |
968808b8 | 1779 | } |
940864dd | 1780 | /* Mark the page as allocated */ |
7be98234 RW |
1781 | swsusp_set_page_forbidden(virt_to_page(lp)); |
1782 | swsusp_set_page_free(virt_to_page(lp)); | |
940864dd | 1783 | nr_pages--; |
968808b8 | 1784 | } |
940864dd RW |
1785 | /* Free the reserved safe pages so that chain_alloc() can use them */ |
1786 | while (sp_list) { | |
1787 | lp = sp_list->next; | |
1788 | free_image_page(sp_list, PG_UNSAFE_CLEAR); | |
1789 | sp_list = lp; | |
f577eb30 | 1790 | } |
940864dd RW |
1791 | return 0; |
1792 | ||
59a49335 | 1793 | Free: |
940864dd | 1794 | swsusp_free(); |
f577eb30 RW |
1795 | return error; |
1796 | } | |
1797 | ||
940864dd RW |
1798 | /** |
1799 | * get_buffer - compute the address that snapshot_write_next() should | |
1800 | * set for its caller to write to. | |
1801 | */ | |
1802 | ||
1803 | static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca) | |
968808b8 | 1804 | { |
940864dd | 1805 | struct pbe *pbe; |
69643279 RW |
1806 | struct page *page; |
1807 | unsigned long pfn = memory_bm_next_pfn(bm); | |
968808b8 | 1808 | |
69643279 RW |
1809 | if (pfn == BM_END_OF_MAP) |
1810 | return ERR_PTR(-EFAULT); | |
1811 | ||
1812 | page = pfn_to_page(pfn); | |
8357376d RW |
1813 | if (PageHighMem(page)) |
1814 | return get_highmem_page_buffer(page, ca); | |
1815 | ||
7be98234 | 1816 | if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page)) |
940864dd RW |
1817 | /* We have allocated the "original" page frame and we can |
1818 | * use it directly to store the loaded page. | |
968808b8 | 1819 | */ |
940864dd RW |
1820 | return page_address(page); |
1821 | ||
1822 | /* The "original" page frame has not been allocated and we have to | |
1823 | * use a "safe" page frame to store the loaded page. | |
968808b8 | 1824 | */ |
940864dd RW |
1825 | pbe = chain_alloc(ca, sizeof(struct pbe)); |
1826 | if (!pbe) { | |
1827 | swsusp_free(); | |
69643279 | 1828 | return ERR_PTR(-ENOMEM); |
940864dd | 1829 | } |
8357376d RW |
1830 | pbe->orig_address = page_address(page); |
1831 | pbe->address = safe_pages_list; | |
940864dd RW |
1832 | safe_pages_list = safe_pages_list->next; |
1833 | pbe->next = restore_pblist; | |
1834 | restore_pblist = pbe; | |
8357376d | 1835 | return pbe->address; |
968808b8 RW |
1836 | } |
1837 | ||
f577eb30 RW |
1838 | /** |
1839 | * snapshot_write_next - used for writing the system memory snapshot. | |
1840 | * | |
1841 | * On the first call to it @handle should point to a zeroed | |
1842 | * snapshot_handle structure. The structure gets updated and a pointer | |
1843 | * to it should be passed to this function every next time. | |
1844 | * | |
1845 | * The @count parameter should contain the number of bytes the caller | |
1846 | * wants to write to the image. It must not be zero. | |
1847 | * | |
1848 | * On success the function returns a positive number. Then, the caller | |
1849 | * is allowed to write up to the returned number of bytes to the memory | |
1850 | * location computed by the data_of() macro. The number returned | |
1851 | * may be smaller than @count, but this only happens if the write would | |
1852 | * cross a page boundary otherwise. | |
1853 | * | |
1854 | * The function returns 0 to indicate the "end of file" condition, | |
1855 | * and a negative number is returned on error. In such cases the | |
1856 | * structure pointed to by @handle is not updated and should not be used | |
1857 | * any more. | |
1858 | */ | |
1859 | ||
1860 | int snapshot_write_next(struct snapshot_handle *handle, size_t count) | |
1861 | { | |
940864dd | 1862 | static struct chain_allocator ca; |
f577eb30 RW |
1863 | int error = 0; |
1864 | ||
940864dd | 1865 | /* Check if we have already loaded the entire image */ |
fb13a28b | 1866 | if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages) |
f577eb30 | 1867 | return 0; |
940864dd | 1868 | |
8357376d RW |
1869 | if (handle->offset == 0) { |
1870 | if (!buffer) | |
1871 | /* This makes the buffer be freed by swsusp_free() */ | |
1872 | buffer = get_image_page(GFP_ATOMIC, PG_ANY); | |
1873 | ||
f577eb30 RW |
1874 | if (!buffer) |
1875 | return -ENOMEM; | |
8357376d | 1876 | |
f577eb30 | 1877 | handle->buffer = buffer; |
8357376d | 1878 | } |
546e0d27 | 1879 | handle->sync_read = 1; |
fb13a28b | 1880 | if (handle->prev < handle->cur) { |
940864dd RW |
1881 | if (handle->prev == 0) { |
1882 | error = load_header(buffer); | |
1883 | if (error) | |
1884 | return error; | |
1885 | ||
1886 | error = memory_bm_create(©_bm, GFP_ATOMIC, PG_ANY); | |
f577eb30 RW |
1887 | if (error) |
1888 | return error; | |
940864dd | 1889 | |
f577eb30 | 1890 | } else if (handle->prev <= nr_meta_pages) { |
69643279 RW |
1891 | error = unpack_orig_pfns(buffer, ©_bm); |
1892 | if (error) | |
1893 | return error; | |
1894 | ||
940864dd RW |
1895 | if (handle->prev == nr_meta_pages) { |
1896 | error = prepare_image(&orig_bm, ©_bm); | |
f577eb30 RW |
1897 | if (error) |
1898 | return error; | |
940864dd RW |
1899 | |
1900 | chain_init(&ca, GFP_ATOMIC, PG_SAFE); | |
1901 | memory_bm_position_reset(&orig_bm); | |
1902 | restore_pblist = NULL; | |
1903 | handle->buffer = get_buffer(&orig_bm, &ca); | |
546e0d27 | 1904 | handle->sync_read = 0; |
69643279 RW |
1905 | if (IS_ERR(handle->buffer)) |
1906 | return PTR_ERR(handle->buffer); | |
f577eb30 RW |
1907 | } |
1908 | } else { | |
8357376d | 1909 | copy_last_highmem_page(); |
940864dd | 1910 | handle->buffer = get_buffer(&orig_bm, &ca); |
69643279 RW |
1911 | if (IS_ERR(handle->buffer)) |
1912 | return PTR_ERR(handle->buffer); | |
8357376d RW |
1913 | if (handle->buffer != buffer) |
1914 | handle->sync_read = 0; | |
f577eb30 | 1915 | } |
fb13a28b | 1916 | handle->prev = handle->cur; |
f577eb30 | 1917 | } |
fb13a28b RW |
1918 | handle->buf_offset = handle->cur_offset; |
1919 | if (handle->cur_offset + count >= PAGE_SIZE) { | |
1920 | count = PAGE_SIZE - handle->cur_offset; | |
1921 | handle->cur_offset = 0; | |
1922 | handle->cur++; | |
f577eb30 | 1923 | } else { |
fb13a28b | 1924 | handle->cur_offset += count; |
f577eb30 RW |
1925 | } |
1926 | handle->offset += count; | |
1927 | return count; | |
1928 | } | |
1929 | ||
8357376d RW |
1930 | /** |
1931 | * snapshot_write_finalize - must be called after the last call to | |
1932 | * snapshot_write_next() in case the last page in the image happens | |
1933 | * to be a highmem page and its contents should be stored in the | |
1934 | * highmem. Additionally, it releases the memory that will not be | |
1935 | * used any more. | |
1936 | */ | |
1937 | ||
1938 | void snapshot_write_finalize(struct snapshot_handle *handle) | |
1939 | { | |
1940 | copy_last_highmem_page(); | |
1941 | /* Free only if we have loaded the image entirely */ | |
1942 | if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages) { | |
1943 | memory_bm_free(&orig_bm, PG_UNSAFE_CLEAR); | |
1944 | free_highmem_data(); | |
1945 | } | |
1946 | } | |
1947 | ||
f577eb30 RW |
1948 | int snapshot_image_loaded(struct snapshot_handle *handle) |
1949 | { | |
8357376d | 1950 | return !(!nr_copy_pages || !last_highmem_page_copied() || |
940864dd RW |
1951 | handle->cur <= nr_meta_pages + nr_copy_pages); |
1952 | } | |
1953 | ||
8357376d RW |
1954 | #ifdef CONFIG_HIGHMEM |
1955 | /* Assumes that @buf is ready and points to a "safe" page */ | |
1956 | static inline void | |
1957 | swap_two_pages_data(struct page *p1, struct page *p2, void *buf) | |
940864dd | 1958 | { |
8357376d RW |
1959 | void *kaddr1, *kaddr2; |
1960 | ||
1961 | kaddr1 = kmap_atomic(p1, KM_USER0); | |
1962 | kaddr2 = kmap_atomic(p2, KM_USER1); | |
1963 | memcpy(buf, kaddr1, PAGE_SIZE); | |
1964 | memcpy(kaddr1, kaddr2, PAGE_SIZE); | |
1965 | memcpy(kaddr2, buf, PAGE_SIZE); | |
1966 | kunmap_atomic(kaddr1, KM_USER0); | |
1967 | kunmap_atomic(kaddr2, KM_USER1); | |
1968 | } | |
1969 | ||
1970 | /** | |
1971 | * restore_highmem - for each highmem page that was allocated before | |
1972 | * the suspend and included in the suspend image, and also has been | |
1973 | * allocated by the "resume" kernel swap its current (ie. "before | |
1974 | * resume") contents with the previous (ie. "before suspend") one. | |
1975 | * | |
1976 | * If the resume eventually fails, we can call this function once | |
1977 | * again and restore the "before resume" highmem state. | |
1978 | */ | |
1979 | ||
1980 | int restore_highmem(void) | |
1981 | { | |
1982 | struct highmem_pbe *pbe = highmem_pblist; | |
1983 | void *buf; | |
1984 | ||
1985 | if (!pbe) | |
1986 | return 0; | |
1987 | ||
1988 | buf = get_image_page(GFP_ATOMIC, PG_SAFE); | |
1989 | if (!buf) | |
1990 | return -ENOMEM; | |
1991 | ||
1992 | while (pbe) { | |
1993 | swap_two_pages_data(pbe->copy_page, pbe->orig_page, buf); | |
1994 | pbe = pbe->next; | |
1995 | } | |
1996 | free_image_page(buf, PG_UNSAFE_CLEAR); | |
1997 | return 0; | |
f577eb30 | 1998 | } |
8357376d | 1999 | #endif /* CONFIG_HIGHMEM */ |