Commit | Line | Data |
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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> | |
25761b6e RW |
28 | |
29 | #include <asm/uaccess.h> | |
30 | #include <asm/mmu_context.h> | |
31 | #include <asm/pgtable.h> | |
32 | #include <asm/tlbflush.h> | |
33 | #include <asm/io.h> | |
34 | ||
25761b6e RW |
35 | #include "power.h" |
36 | ||
74dfd666 RW |
37 | static int swsusp_page_is_free(struct page *); |
38 | static void swsusp_set_page_forbidden(struct page *); | |
39 | static void swsusp_unset_page_forbidden(struct page *); | |
40 | ||
8357376d RW |
41 | /* List of PBEs needed for restoring the pages that were allocated before |
42 | * the suspend and included in the suspend image, but have also been | |
43 | * allocated by the "resume" kernel, so their contents cannot be written | |
44 | * directly to their "original" page frames. | |
45 | */ | |
75534b50 RW |
46 | struct pbe *restore_pblist; |
47 | ||
8357376d | 48 | /* Pointer to an auxiliary buffer (1 page) */ |
940864dd | 49 | static void *buffer; |
7088a5c0 | 50 | |
f6143aa6 RW |
51 | /** |
52 | * @safe_needed - on resume, for storing the PBE list and the image, | |
53 | * we can only use memory pages that do not conflict with the pages | |
8357376d RW |
54 | * used before suspend. The unsafe pages have PageNosaveFree set |
55 | * and we count them using unsafe_pages. | |
f6143aa6 | 56 | * |
8357376d RW |
57 | * Each allocated image page is marked as PageNosave and PageNosaveFree |
58 | * so that swsusp_free() can release it. | |
f6143aa6 RW |
59 | */ |
60 | ||
0bcd888d RW |
61 | #define PG_ANY 0 |
62 | #define PG_SAFE 1 | |
63 | #define PG_UNSAFE_CLEAR 1 | |
64 | #define PG_UNSAFE_KEEP 0 | |
65 | ||
940864dd | 66 | static unsigned int allocated_unsafe_pages; |
f6143aa6 | 67 | |
8357376d | 68 | static void *get_image_page(gfp_t gfp_mask, int safe_needed) |
f6143aa6 RW |
69 | { |
70 | void *res; | |
71 | ||
72 | res = (void *)get_zeroed_page(gfp_mask); | |
73 | if (safe_needed) | |
7be98234 | 74 | while (res && swsusp_page_is_free(virt_to_page(res))) { |
f6143aa6 | 75 | /* The page is unsafe, mark it for swsusp_free() */ |
7be98234 | 76 | swsusp_set_page_forbidden(virt_to_page(res)); |
940864dd | 77 | allocated_unsafe_pages++; |
f6143aa6 RW |
78 | res = (void *)get_zeroed_page(gfp_mask); |
79 | } | |
80 | if (res) { | |
7be98234 RW |
81 | swsusp_set_page_forbidden(virt_to_page(res)); |
82 | swsusp_set_page_free(virt_to_page(res)); | |
f6143aa6 RW |
83 | } |
84 | return res; | |
85 | } | |
86 | ||
87 | unsigned long get_safe_page(gfp_t gfp_mask) | |
88 | { | |
8357376d RW |
89 | return (unsigned long)get_image_page(gfp_mask, PG_SAFE); |
90 | } | |
91 | ||
5b6d15de RW |
92 | static struct page *alloc_image_page(gfp_t gfp_mask) |
93 | { | |
8357376d RW |
94 | struct page *page; |
95 | ||
96 | page = alloc_page(gfp_mask); | |
97 | if (page) { | |
7be98234 RW |
98 | swsusp_set_page_forbidden(page); |
99 | swsusp_set_page_free(page); | |
8357376d RW |
100 | } |
101 | return page; | |
f6143aa6 RW |
102 | } |
103 | ||
104 | /** | |
105 | * free_image_page - free page represented by @addr, allocated with | |
8357376d | 106 | * get_image_page (page flags set by it must be cleared) |
f6143aa6 RW |
107 | */ |
108 | ||
109 | static inline void free_image_page(void *addr, int clear_nosave_free) | |
110 | { | |
8357376d RW |
111 | struct page *page; |
112 | ||
113 | BUG_ON(!virt_addr_valid(addr)); | |
114 | ||
115 | page = virt_to_page(addr); | |
116 | ||
7be98234 | 117 | swsusp_unset_page_forbidden(page); |
f6143aa6 | 118 | if (clear_nosave_free) |
7be98234 | 119 | swsusp_unset_page_free(page); |
8357376d RW |
120 | |
121 | __free_page(page); | |
f6143aa6 RW |
122 | } |
123 | ||
b788db79 RW |
124 | /* struct linked_page is used to build chains of pages */ |
125 | ||
126 | #define LINKED_PAGE_DATA_SIZE (PAGE_SIZE - sizeof(void *)) | |
127 | ||
128 | struct linked_page { | |
129 | struct linked_page *next; | |
130 | char data[LINKED_PAGE_DATA_SIZE]; | |
131 | } __attribute__((packed)); | |
132 | ||
133 | static inline void | |
134 | free_list_of_pages(struct linked_page *list, int clear_page_nosave) | |
135 | { | |
136 | while (list) { | |
137 | struct linked_page *lp = list->next; | |
138 | ||
139 | free_image_page(list, clear_page_nosave); | |
140 | list = lp; | |
141 | } | |
142 | } | |
143 | ||
144 | /** | |
145 | * struct chain_allocator is used for allocating small objects out of | |
146 | * a linked list of pages called 'the chain'. | |
147 | * | |
148 | * The chain grows each time when there is no room for a new object in | |
149 | * the current page. The allocated objects cannot be freed individually. | |
150 | * It is only possible to free them all at once, by freeing the entire | |
151 | * chain. | |
152 | * | |
153 | * NOTE: The chain allocator may be inefficient if the allocated objects | |
154 | * are not much smaller than PAGE_SIZE. | |
155 | */ | |
156 | ||
157 | struct chain_allocator { | |
158 | struct linked_page *chain; /* the chain */ | |
159 | unsigned int used_space; /* total size of objects allocated out | |
160 | * of the current page | |
161 | */ | |
162 | gfp_t gfp_mask; /* mask for allocating pages */ | |
163 | int safe_needed; /* if set, only "safe" pages are allocated */ | |
164 | }; | |
165 | ||
166 | static void | |
167 | chain_init(struct chain_allocator *ca, gfp_t gfp_mask, int safe_needed) | |
168 | { | |
169 | ca->chain = NULL; | |
170 | ca->used_space = LINKED_PAGE_DATA_SIZE; | |
171 | ca->gfp_mask = gfp_mask; | |
172 | ca->safe_needed = safe_needed; | |
173 | } | |
174 | ||
175 | static void *chain_alloc(struct chain_allocator *ca, unsigned int size) | |
176 | { | |
177 | void *ret; | |
178 | ||
179 | if (LINKED_PAGE_DATA_SIZE - ca->used_space < size) { | |
180 | struct linked_page *lp; | |
181 | ||
8357376d | 182 | lp = get_image_page(ca->gfp_mask, ca->safe_needed); |
b788db79 RW |
183 | if (!lp) |
184 | return NULL; | |
185 | ||
186 | lp->next = ca->chain; | |
187 | ca->chain = lp; | |
188 | ca->used_space = 0; | |
189 | } | |
190 | ret = ca->chain->data + ca->used_space; | |
191 | ca->used_space += size; | |
192 | return ret; | |
193 | } | |
194 | ||
195 | static void chain_free(struct chain_allocator *ca, int clear_page_nosave) | |
196 | { | |
197 | free_list_of_pages(ca->chain, clear_page_nosave); | |
198 | memset(ca, 0, sizeof(struct chain_allocator)); | |
199 | } | |
200 | ||
201 | /** | |
202 | * Data types related to memory bitmaps. | |
203 | * | |
204 | * Memory bitmap is a structure consiting of many linked lists of | |
205 | * objects. The main list's elements are of type struct zone_bitmap | |
206 | * and each of them corresonds to one zone. For each zone bitmap | |
207 | * object there is a list of objects of type struct bm_block that | |
208 | * represent each blocks of bit chunks in which information is | |
209 | * stored. | |
210 | * | |
211 | * struct memory_bitmap contains a pointer to the main list of zone | |
212 | * bitmap objects, a struct bm_position used for browsing the bitmap, | |
213 | * and a pointer to the list of pages used for allocating all of the | |
214 | * zone bitmap objects and bitmap block objects. | |
215 | * | |
216 | * NOTE: It has to be possible to lay out the bitmap in memory | |
217 | * using only allocations of order 0. Additionally, the bitmap is | |
218 | * designed to work with arbitrary number of zones (this is over the | |
219 | * top for now, but let's avoid making unnecessary assumptions ;-). | |
220 | * | |
221 | * struct zone_bitmap contains a pointer to a list of bitmap block | |
222 | * objects and a pointer to the bitmap block object that has been | |
223 | * most recently used for setting bits. Additionally, it contains the | |
224 | * pfns that correspond to the start and end of the represented zone. | |
225 | * | |
226 | * struct bm_block contains a pointer to the memory page in which | |
227 | * information is stored (in the form of a block of bit chunks | |
228 | * of type unsigned long each). It also contains the pfns that | |
229 | * correspond to the start and end of the represented memory area and | |
230 | * the number of bit chunks in the block. | |
b788db79 RW |
231 | */ |
232 | ||
233 | #define BM_END_OF_MAP (~0UL) | |
234 | ||
235 | #define BM_CHUNKS_PER_BLOCK (PAGE_SIZE / sizeof(long)) | |
236 | #define BM_BITS_PER_CHUNK (sizeof(long) << 3) | |
237 | #define BM_BITS_PER_BLOCK (PAGE_SIZE << 3) | |
238 | ||
239 | struct bm_block { | |
240 | struct bm_block *next; /* next element of the list */ | |
241 | unsigned long start_pfn; /* pfn represented by the first bit */ | |
242 | unsigned long end_pfn; /* pfn represented by the last bit plus 1 */ | |
243 | unsigned int size; /* number of bit chunks */ | |
244 | unsigned long *data; /* chunks of bits representing pages */ | |
245 | }; | |
246 | ||
247 | struct zone_bitmap { | |
248 | struct zone_bitmap *next; /* next element of the list */ | |
249 | unsigned long start_pfn; /* minimal pfn in this zone */ | |
250 | unsigned long end_pfn; /* maximal pfn in this zone plus 1 */ | |
251 | struct bm_block *bm_blocks; /* list of bitmap blocks */ | |
252 | struct bm_block *cur_block; /* recently used bitmap block */ | |
253 | }; | |
254 | ||
255 | /* strcut bm_position is used for browsing memory bitmaps */ | |
256 | ||
257 | struct bm_position { | |
258 | struct zone_bitmap *zone_bm; | |
259 | struct bm_block *block; | |
260 | int chunk; | |
261 | int bit; | |
262 | }; | |
263 | ||
264 | struct memory_bitmap { | |
265 | struct zone_bitmap *zone_bm_list; /* list of zone bitmaps */ | |
266 | struct linked_page *p_list; /* list of pages used to store zone | |
267 | * bitmap objects and bitmap block | |
268 | * objects | |
269 | */ | |
270 | struct bm_position cur; /* most recently used bit position */ | |
271 | }; | |
272 | ||
273 | /* Functions that operate on memory bitmaps */ | |
274 | ||
275 | static inline void memory_bm_reset_chunk(struct memory_bitmap *bm) | |
276 | { | |
277 | bm->cur.chunk = 0; | |
278 | bm->cur.bit = -1; | |
279 | } | |
280 | ||
281 | static void memory_bm_position_reset(struct memory_bitmap *bm) | |
282 | { | |
283 | struct zone_bitmap *zone_bm; | |
284 | ||
285 | zone_bm = bm->zone_bm_list; | |
286 | bm->cur.zone_bm = zone_bm; | |
287 | bm->cur.block = zone_bm->bm_blocks; | |
288 | memory_bm_reset_chunk(bm); | |
289 | } | |
290 | ||
291 | static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free); | |
292 | ||
293 | /** | |
294 | * create_bm_block_list - create a list of block bitmap objects | |
295 | */ | |
296 | ||
297 | static inline struct bm_block * | |
298 | create_bm_block_list(unsigned int nr_blocks, struct chain_allocator *ca) | |
299 | { | |
300 | struct bm_block *bblist = NULL; | |
301 | ||
302 | while (nr_blocks-- > 0) { | |
303 | struct bm_block *bb; | |
304 | ||
305 | bb = chain_alloc(ca, sizeof(struct bm_block)); | |
306 | if (!bb) | |
307 | return NULL; | |
308 | ||
309 | bb->next = bblist; | |
310 | bblist = bb; | |
311 | } | |
312 | return bblist; | |
313 | } | |
314 | ||
315 | /** | |
316 | * create_zone_bm_list - create a list of zone bitmap objects | |
317 | */ | |
318 | ||
319 | static inline struct zone_bitmap * | |
320 | create_zone_bm_list(unsigned int nr_zones, struct chain_allocator *ca) | |
321 | { | |
322 | struct zone_bitmap *zbmlist = NULL; | |
323 | ||
324 | while (nr_zones-- > 0) { | |
325 | struct zone_bitmap *zbm; | |
326 | ||
327 | zbm = chain_alloc(ca, sizeof(struct zone_bitmap)); | |
328 | if (!zbm) | |
329 | return NULL; | |
330 | ||
331 | zbm->next = zbmlist; | |
332 | zbmlist = zbm; | |
333 | } | |
334 | return zbmlist; | |
335 | } | |
336 | ||
337 | /** | |
338 | * memory_bm_create - allocate memory for a memory bitmap | |
339 | */ | |
340 | ||
341 | static int | |
342 | memory_bm_create(struct memory_bitmap *bm, gfp_t gfp_mask, int safe_needed) | |
343 | { | |
344 | struct chain_allocator ca; | |
345 | struct zone *zone; | |
346 | struct zone_bitmap *zone_bm; | |
347 | struct bm_block *bb; | |
348 | unsigned int nr; | |
349 | ||
350 | chain_init(&ca, gfp_mask, safe_needed); | |
351 | ||
352 | /* Compute the number of zones */ | |
353 | nr = 0; | |
8357376d RW |
354 | for_each_zone(zone) |
355 | if (populated_zone(zone)) | |
b788db79 RW |
356 | nr++; |
357 | ||
358 | /* Allocate the list of zones bitmap objects */ | |
359 | zone_bm = create_zone_bm_list(nr, &ca); | |
360 | bm->zone_bm_list = zone_bm; | |
361 | if (!zone_bm) { | |
362 | chain_free(&ca, PG_UNSAFE_CLEAR); | |
363 | return -ENOMEM; | |
364 | } | |
365 | ||
366 | /* Initialize the zone bitmap objects */ | |
8357376d | 367 | for_each_zone(zone) { |
b788db79 RW |
368 | unsigned long pfn; |
369 | ||
8357376d | 370 | if (!populated_zone(zone)) |
b788db79 RW |
371 | continue; |
372 | ||
373 | zone_bm->start_pfn = zone->zone_start_pfn; | |
374 | zone_bm->end_pfn = zone->zone_start_pfn + zone->spanned_pages; | |
375 | /* Allocate the list of bitmap block objects */ | |
376 | nr = DIV_ROUND_UP(zone->spanned_pages, BM_BITS_PER_BLOCK); | |
377 | bb = create_bm_block_list(nr, &ca); | |
378 | zone_bm->bm_blocks = bb; | |
379 | zone_bm->cur_block = bb; | |
380 | if (!bb) | |
381 | goto Free; | |
382 | ||
383 | nr = zone->spanned_pages; | |
384 | pfn = zone->zone_start_pfn; | |
385 | /* Initialize the bitmap block objects */ | |
386 | while (bb) { | |
387 | unsigned long *ptr; | |
388 | ||
8357376d | 389 | ptr = get_image_page(gfp_mask, safe_needed); |
b788db79 RW |
390 | bb->data = ptr; |
391 | if (!ptr) | |
392 | goto Free; | |
393 | ||
394 | bb->start_pfn = pfn; | |
395 | if (nr >= BM_BITS_PER_BLOCK) { | |
396 | pfn += BM_BITS_PER_BLOCK; | |
397 | bb->size = BM_CHUNKS_PER_BLOCK; | |
398 | nr -= BM_BITS_PER_BLOCK; | |
399 | } else { | |
400 | /* This is executed only once in the loop */ | |
401 | pfn += nr; | |
402 | bb->size = DIV_ROUND_UP(nr, BM_BITS_PER_CHUNK); | |
403 | } | |
404 | bb->end_pfn = pfn; | |
405 | bb = bb->next; | |
406 | } | |
407 | zone_bm = zone_bm->next; | |
408 | } | |
409 | bm->p_list = ca.chain; | |
410 | memory_bm_position_reset(bm); | |
411 | return 0; | |
412 | ||
59a49335 | 413 | Free: |
b788db79 RW |
414 | bm->p_list = ca.chain; |
415 | memory_bm_free(bm, PG_UNSAFE_CLEAR); | |
416 | return -ENOMEM; | |
417 | } | |
418 | ||
419 | /** | |
420 | * memory_bm_free - free memory occupied by the memory bitmap @bm | |
421 | */ | |
422 | ||
423 | static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free) | |
424 | { | |
425 | struct zone_bitmap *zone_bm; | |
426 | ||
427 | /* Free the list of bit blocks for each zone_bitmap object */ | |
428 | zone_bm = bm->zone_bm_list; | |
429 | while (zone_bm) { | |
430 | struct bm_block *bb; | |
431 | ||
432 | bb = zone_bm->bm_blocks; | |
433 | while (bb) { | |
434 | if (bb->data) | |
435 | free_image_page(bb->data, clear_nosave_free); | |
436 | bb = bb->next; | |
437 | } | |
438 | zone_bm = zone_bm->next; | |
439 | } | |
440 | free_list_of_pages(bm->p_list, clear_nosave_free); | |
441 | bm->zone_bm_list = NULL; | |
442 | } | |
443 | ||
444 | /** | |
74dfd666 | 445 | * memory_bm_find_bit - find the bit in the bitmap @bm that corresponds |
b788db79 RW |
446 | * to given pfn. The cur_zone_bm member of @bm and the cur_block member |
447 | * of @bm->cur_zone_bm are updated. | |
b788db79 RW |
448 | */ |
449 | ||
74dfd666 RW |
450 | static void memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn, |
451 | void **addr, unsigned int *bit_nr) | |
b788db79 RW |
452 | { |
453 | struct zone_bitmap *zone_bm; | |
454 | struct bm_block *bb; | |
455 | ||
456 | /* Check if the pfn is from the current zone */ | |
457 | zone_bm = bm->cur.zone_bm; | |
458 | if (pfn < zone_bm->start_pfn || pfn >= zone_bm->end_pfn) { | |
459 | zone_bm = bm->zone_bm_list; | |
460 | /* We don't assume that the zones are sorted by pfns */ | |
461 | while (pfn < zone_bm->start_pfn || pfn >= zone_bm->end_pfn) { | |
462 | zone_bm = zone_bm->next; | |
74dfd666 RW |
463 | |
464 | BUG_ON(!zone_bm); | |
b788db79 RW |
465 | } |
466 | bm->cur.zone_bm = zone_bm; | |
467 | } | |
468 | /* Check if the pfn corresponds to the current bitmap block */ | |
469 | bb = zone_bm->cur_block; | |
470 | if (pfn < bb->start_pfn) | |
471 | bb = zone_bm->bm_blocks; | |
472 | ||
473 | while (pfn >= bb->end_pfn) { | |
474 | bb = bb->next; | |
74dfd666 RW |
475 | |
476 | BUG_ON(!bb); | |
b788db79 RW |
477 | } |
478 | zone_bm->cur_block = bb; | |
479 | pfn -= bb->start_pfn; | |
74dfd666 RW |
480 | *bit_nr = pfn % BM_BITS_PER_CHUNK; |
481 | *addr = bb->data + pfn / BM_BITS_PER_CHUNK; | |
482 | } | |
483 | ||
484 | static void memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn) | |
485 | { | |
486 | void *addr; | |
487 | unsigned int bit; | |
488 | ||
489 | memory_bm_find_bit(bm, pfn, &addr, &bit); | |
490 | set_bit(bit, addr); | |
491 | } | |
492 | ||
493 | static void memory_bm_clear_bit(struct memory_bitmap *bm, unsigned long pfn) | |
494 | { | |
495 | void *addr; | |
496 | unsigned int bit; | |
497 | ||
498 | memory_bm_find_bit(bm, pfn, &addr, &bit); | |
499 | clear_bit(bit, addr); | |
500 | } | |
501 | ||
502 | static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn) | |
503 | { | |
504 | void *addr; | |
505 | unsigned int bit; | |
506 | ||
507 | memory_bm_find_bit(bm, pfn, &addr, &bit); | |
508 | return test_bit(bit, addr); | |
b788db79 RW |
509 | } |
510 | ||
511 | /* Two auxiliary functions for memory_bm_next_pfn */ | |
512 | ||
513 | /* Find the first set bit in the given chunk, if there is one */ | |
514 | ||
515 | static inline int next_bit_in_chunk(int bit, unsigned long *chunk_p) | |
516 | { | |
517 | bit++; | |
518 | while (bit < BM_BITS_PER_CHUNK) { | |
519 | if (test_bit(bit, chunk_p)) | |
520 | return bit; | |
521 | ||
522 | bit++; | |
523 | } | |
524 | return -1; | |
525 | } | |
526 | ||
527 | /* Find a chunk containing some bits set in given block of bits */ | |
528 | ||
529 | static inline int next_chunk_in_block(int n, struct bm_block *bb) | |
530 | { | |
531 | n++; | |
532 | while (n < bb->size) { | |
533 | if (bb->data[n]) | |
534 | return n; | |
535 | ||
536 | n++; | |
537 | } | |
538 | return -1; | |
539 | } | |
540 | ||
541 | /** | |
542 | * memory_bm_next_pfn - find the pfn that corresponds to the next set bit | |
543 | * in the bitmap @bm. If the pfn cannot be found, BM_END_OF_MAP is | |
544 | * returned. | |
545 | * | |
546 | * It is required to run memory_bm_position_reset() before the first call to | |
547 | * this function. | |
548 | */ | |
549 | ||
550 | static unsigned long memory_bm_next_pfn(struct memory_bitmap *bm) | |
551 | { | |
552 | struct zone_bitmap *zone_bm; | |
553 | struct bm_block *bb; | |
554 | int chunk; | |
555 | int bit; | |
556 | ||
557 | do { | |
558 | bb = bm->cur.block; | |
559 | do { | |
560 | chunk = bm->cur.chunk; | |
561 | bit = bm->cur.bit; | |
562 | do { | |
563 | bit = next_bit_in_chunk(bit, bb->data + chunk); | |
564 | if (bit >= 0) | |
565 | goto Return_pfn; | |
566 | ||
567 | chunk = next_chunk_in_block(chunk, bb); | |
568 | bit = -1; | |
569 | } while (chunk >= 0); | |
570 | bb = bb->next; | |
571 | bm->cur.block = bb; | |
572 | memory_bm_reset_chunk(bm); | |
573 | } while (bb); | |
574 | zone_bm = bm->cur.zone_bm->next; | |
575 | if (zone_bm) { | |
576 | bm->cur.zone_bm = zone_bm; | |
577 | bm->cur.block = zone_bm->bm_blocks; | |
578 | memory_bm_reset_chunk(bm); | |
579 | } | |
580 | } while (zone_bm); | |
581 | memory_bm_position_reset(bm); | |
582 | return BM_END_OF_MAP; | |
583 | ||
59a49335 | 584 | Return_pfn: |
b788db79 RW |
585 | bm->cur.chunk = chunk; |
586 | bm->cur.bit = bit; | |
587 | return bb->start_pfn + chunk * BM_BITS_PER_CHUNK + bit; | |
588 | } | |
589 | ||
74dfd666 RW |
590 | /** |
591 | * This structure represents a range of page frames the contents of which | |
592 | * should not be saved during the suspend. | |
593 | */ | |
594 | ||
595 | struct nosave_region { | |
596 | struct list_head list; | |
597 | unsigned long start_pfn; | |
598 | unsigned long end_pfn; | |
599 | }; | |
600 | ||
601 | static LIST_HEAD(nosave_regions); | |
602 | ||
603 | /** | |
604 | * register_nosave_region - register a range of page frames the contents | |
605 | * of which should not be saved during the suspend (to be used in the early | |
606 | * initialization code) | |
607 | */ | |
608 | ||
609 | void __init | |
940d67f6 JB |
610 | __register_nosave_region(unsigned long start_pfn, unsigned long end_pfn, |
611 | int use_kmalloc) | |
74dfd666 RW |
612 | { |
613 | struct nosave_region *region; | |
614 | ||
615 | if (start_pfn >= end_pfn) | |
616 | return; | |
617 | ||
618 | if (!list_empty(&nosave_regions)) { | |
619 | /* Try to extend the previous region (they should be sorted) */ | |
620 | region = list_entry(nosave_regions.prev, | |
621 | struct nosave_region, list); | |
622 | if (region->end_pfn == start_pfn) { | |
623 | region->end_pfn = end_pfn; | |
624 | goto Report; | |
625 | } | |
626 | } | |
940d67f6 JB |
627 | if (use_kmalloc) { |
628 | /* during init, this shouldn't fail */ | |
629 | region = kmalloc(sizeof(struct nosave_region), GFP_KERNEL); | |
630 | BUG_ON(!region); | |
631 | } else | |
632 | /* This allocation cannot fail */ | |
633 | region = alloc_bootmem_low(sizeof(struct nosave_region)); | |
74dfd666 RW |
634 | region->start_pfn = start_pfn; |
635 | region->end_pfn = end_pfn; | |
636 | list_add_tail(®ion->list, &nosave_regions); | |
637 | Report: | |
638 | printk("swsusp: Registered nosave memory region: %016lx - %016lx\n", | |
639 | start_pfn << PAGE_SHIFT, end_pfn << PAGE_SHIFT); | |
640 | } | |
641 | ||
642 | /* | |
643 | * Set bits in this map correspond to the page frames the contents of which | |
644 | * should not be saved during the suspend. | |
645 | */ | |
646 | static struct memory_bitmap *forbidden_pages_map; | |
647 | ||
648 | /* Set bits in this map correspond to free page frames. */ | |
649 | static struct memory_bitmap *free_pages_map; | |
650 | ||
651 | /* | |
652 | * Each page frame allocated for creating the image is marked by setting the | |
653 | * corresponding bits in forbidden_pages_map and free_pages_map simultaneously | |
654 | */ | |
655 | ||
656 | void swsusp_set_page_free(struct page *page) | |
657 | { | |
658 | if (free_pages_map) | |
659 | memory_bm_set_bit(free_pages_map, page_to_pfn(page)); | |
660 | } | |
661 | ||
662 | static int swsusp_page_is_free(struct page *page) | |
663 | { | |
664 | return free_pages_map ? | |
665 | memory_bm_test_bit(free_pages_map, page_to_pfn(page)) : 0; | |
666 | } | |
667 | ||
668 | void swsusp_unset_page_free(struct page *page) | |
669 | { | |
670 | if (free_pages_map) | |
671 | memory_bm_clear_bit(free_pages_map, page_to_pfn(page)); | |
672 | } | |
673 | ||
674 | static void swsusp_set_page_forbidden(struct page *page) | |
675 | { | |
676 | if (forbidden_pages_map) | |
677 | memory_bm_set_bit(forbidden_pages_map, page_to_pfn(page)); | |
678 | } | |
679 | ||
680 | int swsusp_page_is_forbidden(struct page *page) | |
681 | { | |
682 | return forbidden_pages_map ? | |
683 | memory_bm_test_bit(forbidden_pages_map, page_to_pfn(page)) : 0; | |
684 | } | |
685 | ||
686 | static void swsusp_unset_page_forbidden(struct page *page) | |
687 | { | |
688 | if (forbidden_pages_map) | |
689 | memory_bm_clear_bit(forbidden_pages_map, page_to_pfn(page)); | |
690 | } | |
691 | ||
692 | /** | |
693 | * mark_nosave_pages - set bits corresponding to the page frames the | |
694 | * contents of which should not be saved in a given bitmap. | |
695 | */ | |
696 | ||
697 | static void mark_nosave_pages(struct memory_bitmap *bm) | |
698 | { | |
699 | struct nosave_region *region; | |
700 | ||
701 | if (list_empty(&nosave_regions)) | |
702 | return; | |
703 | ||
704 | list_for_each_entry(region, &nosave_regions, list) { | |
705 | unsigned long pfn; | |
706 | ||
707 | printk("swsusp: Marking nosave pages: %016lx - %016lx\n", | |
708 | region->start_pfn << PAGE_SHIFT, | |
709 | region->end_pfn << PAGE_SHIFT); | |
710 | ||
711 | for (pfn = region->start_pfn; pfn < region->end_pfn; pfn++) | |
712 | memory_bm_set_bit(bm, pfn); | |
713 | } | |
714 | } | |
715 | ||
716 | /** | |
717 | * create_basic_memory_bitmaps - create bitmaps needed for marking page | |
718 | * frames that should not be saved and free page frames. The pointers | |
719 | * forbidden_pages_map and free_pages_map are only modified if everything | |
720 | * goes well, because we don't want the bits to be used before both bitmaps | |
721 | * are set up. | |
722 | */ | |
723 | ||
724 | int create_basic_memory_bitmaps(void) | |
725 | { | |
726 | struct memory_bitmap *bm1, *bm2; | |
727 | int error = 0; | |
728 | ||
729 | BUG_ON(forbidden_pages_map || free_pages_map); | |
730 | ||
0709db60 | 731 | bm1 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL); |
74dfd666 RW |
732 | if (!bm1) |
733 | return -ENOMEM; | |
734 | ||
0709db60 | 735 | error = memory_bm_create(bm1, GFP_KERNEL, PG_ANY); |
74dfd666 RW |
736 | if (error) |
737 | goto Free_first_object; | |
738 | ||
0709db60 | 739 | bm2 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL); |
74dfd666 RW |
740 | if (!bm2) |
741 | goto Free_first_bitmap; | |
742 | ||
0709db60 | 743 | error = memory_bm_create(bm2, GFP_KERNEL, PG_ANY); |
74dfd666 RW |
744 | if (error) |
745 | goto Free_second_object; | |
746 | ||
747 | forbidden_pages_map = bm1; | |
748 | free_pages_map = bm2; | |
749 | mark_nosave_pages(forbidden_pages_map); | |
750 | ||
751 | printk("swsusp: Basic memory bitmaps created\n"); | |
752 | ||
753 | return 0; | |
754 | ||
755 | Free_second_object: | |
756 | kfree(bm2); | |
757 | Free_first_bitmap: | |
758 | memory_bm_free(bm1, PG_UNSAFE_CLEAR); | |
759 | Free_first_object: | |
760 | kfree(bm1); | |
761 | return -ENOMEM; | |
762 | } | |
763 | ||
764 | /** | |
765 | * free_basic_memory_bitmaps - free memory bitmaps allocated by | |
766 | * create_basic_memory_bitmaps(). The auxiliary pointers are necessary | |
767 | * so that the bitmaps themselves are not referred to while they are being | |
768 | * freed. | |
769 | */ | |
770 | ||
771 | void free_basic_memory_bitmaps(void) | |
772 | { | |
773 | struct memory_bitmap *bm1, *bm2; | |
774 | ||
775 | BUG_ON(!(forbidden_pages_map && free_pages_map)); | |
776 | ||
777 | bm1 = forbidden_pages_map; | |
778 | bm2 = free_pages_map; | |
779 | forbidden_pages_map = NULL; | |
780 | free_pages_map = NULL; | |
781 | memory_bm_free(bm1, PG_UNSAFE_CLEAR); | |
782 | kfree(bm1); | |
783 | memory_bm_free(bm2, PG_UNSAFE_CLEAR); | |
784 | kfree(bm2); | |
785 | ||
786 | printk("swsusp: Basic memory bitmaps freed\n"); | |
787 | } | |
788 | ||
b788db79 RW |
789 | /** |
790 | * snapshot_additional_pages - estimate the number of additional pages | |
791 | * be needed for setting up the suspend image data structures for given | |
792 | * zone (usually the returned value is greater than the exact number) | |
793 | */ | |
794 | ||
795 | unsigned int snapshot_additional_pages(struct zone *zone) | |
796 | { | |
797 | unsigned int res; | |
798 | ||
799 | res = DIV_ROUND_UP(zone->spanned_pages, BM_BITS_PER_BLOCK); | |
800 | res += DIV_ROUND_UP(res * sizeof(struct bm_block), PAGE_SIZE); | |
8357376d | 801 | return 2 * res; |
b788db79 RW |
802 | } |
803 | ||
8357376d RW |
804 | #ifdef CONFIG_HIGHMEM |
805 | /** | |
806 | * count_free_highmem_pages - compute the total number of free highmem | |
807 | * pages, system-wide. | |
808 | */ | |
809 | ||
810 | static unsigned int count_free_highmem_pages(void) | |
811 | { | |
812 | struct zone *zone; | |
813 | unsigned int cnt = 0; | |
814 | ||
815 | for_each_zone(zone) | |
816 | if (populated_zone(zone) && is_highmem(zone)) | |
d23ad423 | 817 | cnt += zone_page_state(zone, NR_FREE_PAGES); |
8357376d RW |
818 | |
819 | return cnt; | |
820 | } | |
821 | ||
822 | /** | |
823 | * saveable_highmem_page - Determine whether a highmem page should be | |
824 | * included in the suspend image. | |
825 | * | |
826 | * We should save the page if it isn't Nosave or NosaveFree, or Reserved, | |
827 | * and it isn't a part of a free chunk of pages. | |
828 | */ | |
829 | ||
830 | static struct page *saveable_highmem_page(unsigned long pfn) | |
831 | { | |
832 | struct page *page; | |
833 | ||
834 | if (!pfn_valid(pfn)) | |
835 | return NULL; | |
836 | ||
837 | page = pfn_to_page(pfn); | |
838 | ||
839 | BUG_ON(!PageHighMem(page)); | |
840 | ||
7be98234 RW |
841 | if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page) || |
842 | PageReserved(page)) | |
8357376d RW |
843 | return NULL; |
844 | ||
845 | return page; | |
846 | } | |
847 | ||
848 | /** | |
849 | * count_highmem_pages - compute the total number of saveable highmem | |
850 | * pages. | |
851 | */ | |
852 | ||
853 | unsigned int count_highmem_pages(void) | |
854 | { | |
855 | struct zone *zone; | |
856 | unsigned int n = 0; | |
857 | ||
858 | for_each_zone(zone) { | |
859 | unsigned long pfn, max_zone_pfn; | |
860 | ||
861 | if (!is_highmem(zone)) | |
862 | continue; | |
863 | ||
864 | mark_free_pages(zone); | |
865 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; | |
866 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
867 | if (saveable_highmem_page(pfn)) | |
868 | n++; | |
869 | } | |
870 | return n; | |
871 | } | |
872 | #else | |
873 | static inline void *saveable_highmem_page(unsigned long pfn) { return NULL; } | |
874 | static inline unsigned int count_highmem_pages(void) { return 0; } | |
875 | #endif /* CONFIG_HIGHMEM */ | |
876 | ||
25761b6e | 877 | /** |
8357376d RW |
878 | * saveable - Determine whether a non-highmem page should be included in |
879 | * 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 RW |
884 | */ |
885 | ||
ae83c5ee | 886 | static struct page *saveable_page(unsigned long pfn) |
25761b6e | 887 | { |
de491861 | 888 | struct page *page; |
25761b6e RW |
889 | |
890 | if (!pfn_valid(pfn)) | |
ae83c5ee | 891 | return NULL; |
25761b6e RW |
892 | |
893 | page = pfn_to_page(pfn); | |
ae83c5ee | 894 | |
8357376d RW |
895 | BUG_ON(PageHighMem(page)); |
896 | ||
7be98234 | 897 | if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page)) |
ae83c5ee | 898 | return NULL; |
8357376d | 899 | |
72a97e08 | 900 | if (PageReserved(page) && pfn_is_nosave(pfn)) |
ae83c5ee | 901 | return NULL; |
25761b6e | 902 | |
ae83c5ee | 903 | return page; |
25761b6e RW |
904 | } |
905 | ||
8357376d RW |
906 | /** |
907 | * count_data_pages - compute the total number of saveable non-highmem | |
908 | * pages. | |
909 | */ | |
910 | ||
72a97e08 | 911 | unsigned int count_data_pages(void) |
25761b6e RW |
912 | { |
913 | struct zone *zone; | |
ae83c5ee | 914 | unsigned long pfn, max_zone_pfn; |
dc19d507 | 915 | unsigned int n = 0; |
25761b6e | 916 | |
8357376d | 917 | for_each_zone(zone) { |
25761b6e RW |
918 | if (is_highmem(zone)) |
919 | continue; | |
8357376d | 920 | |
25761b6e | 921 | mark_free_pages(zone); |
ae83c5ee RW |
922 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
923 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
8357376d RW |
924 | if(saveable_page(pfn)) |
925 | n++; | |
25761b6e | 926 | } |
a0f49651 | 927 | return n; |
25761b6e RW |
928 | } |
929 | ||
8357376d RW |
930 | /* This is needed, because copy_page and memcpy are not usable for copying |
931 | * task structs. | |
932 | */ | |
933 | static inline void do_copy_page(long *dst, long *src) | |
f623f0db RW |
934 | { |
935 | int n; | |
936 | ||
f623f0db RW |
937 | for (n = PAGE_SIZE / sizeof(long); n; n--) |
938 | *dst++ = *src++; | |
939 | } | |
940 | ||
8357376d RW |
941 | #ifdef CONFIG_HIGHMEM |
942 | static inline struct page * | |
943 | page_is_saveable(struct zone *zone, unsigned long pfn) | |
944 | { | |
945 | return is_highmem(zone) ? | |
946 | saveable_highmem_page(pfn) : saveable_page(pfn); | |
947 | } | |
948 | ||
949 | static inline void | |
950 | copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) | |
951 | { | |
952 | struct page *s_page, *d_page; | |
953 | void *src, *dst; | |
954 | ||
955 | s_page = pfn_to_page(src_pfn); | |
956 | d_page = pfn_to_page(dst_pfn); | |
957 | if (PageHighMem(s_page)) { | |
958 | src = kmap_atomic(s_page, KM_USER0); | |
959 | dst = kmap_atomic(d_page, KM_USER1); | |
960 | do_copy_page(dst, src); | |
961 | kunmap_atomic(src, KM_USER0); | |
962 | kunmap_atomic(dst, KM_USER1); | |
963 | } else { | |
964 | src = page_address(s_page); | |
965 | if (PageHighMem(d_page)) { | |
966 | /* Page pointed to by src may contain some kernel | |
967 | * data modified by kmap_atomic() | |
968 | */ | |
969 | do_copy_page(buffer, src); | |
970 | dst = kmap_atomic(pfn_to_page(dst_pfn), KM_USER0); | |
971 | memcpy(dst, buffer, PAGE_SIZE); | |
972 | kunmap_atomic(dst, KM_USER0); | |
973 | } else { | |
974 | dst = page_address(d_page); | |
975 | do_copy_page(dst, src); | |
976 | } | |
977 | } | |
978 | } | |
979 | #else | |
980 | #define page_is_saveable(zone, pfn) saveable_page(pfn) | |
981 | ||
982 | static inline void | |
983 | copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) | |
984 | { | |
985 | do_copy_page(page_address(pfn_to_page(dst_pfn)), | |
986 | page_address(pfn_to_page(src_pfn))); | |
987 | } | |
988 | #endif /* CONFIG_HIGHMEM */ | |
989 | ||
b788db79 RW |
990 | static void |
991 | copy_data_pages(struct memory_bitmap *copy_bm, struct memory_bitmap *orig_bm) | |
25761b6e RW |
992 | { |
993 | struct zone *zone; | |
b788db79 | 994 | unsigned long pfn; |
25761b6e | 995 | |
8357376d | 996 | for_each_zone(zone) { |
b788db79 RW |
997 | unsigned long max_zone_pfn; |
998 | ||
25761b6e | 999 | mark_free_pages(zone); |
ae83c5ee | 1000 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
b788db79 | 1001 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) |
8357376d | 1002 | if (page_is_saveable(zone, pfn)) |
b788db79 | 1003 | memory_bm_set_bit(orig_bm, pfn); |
25761b6e | 1004 | } |
b788db79 RW |
1005 | memory_bm_position_reset(orig_bm); |
1006 | memory_bm_position_reset(copy_bm); | |
1007 | do { | |
1008 | pfn = memory_bm_next_pfn(orig_bm); | |
8357376d RW |
1009 | if (likely(pfn != BM_END_OF_MAP)) |
1010 | copy_data_page(memory_bm_next_pfn(copy_bm), pfn); | |
b788db79 | 1011 | } while (pfn != BM_END_OF_MAP); |
25761b6e RW |
1012 | } |
1013 | ||
8357376d RW |
1014 | /* Total number of image pages */ |
1015 | static unsigned int nr_copy_pages; | |
1016 | /* Number of pages needed for saving the original pfns of the image pages */ | |
1017 | static unsigned int nr_meta_pages; | |
1018 | ||
25761b6e | 1019 | /** |
940864dd | 1020 | * swsusp_free - free pages allocated for the suspend. |
cd560bb2 | 1021 | * |
940864dd RW |
1022 | * Suspend pages are alocated before the atomic copy is made, so we |
1023 | * need to release them after the resume. | |
25761b6e RW |
1024 | */ |
1025 | ||
1026 | void swsusp_free(void) | |
1027 | { | |
1028 | struct zone *zone; | |
ae83c5ee | 1029 | unsigned long pfn, max_zone_pfn; |
25761b6e RW |
1030 | |
1031 | for_each_zone(zone) { | |
ae83c5ee RW |
1032 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
1033 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
1034 | if (pfn_valid(pfn)) { | |
1035 | struct page *page = pfn_to_page(pfn); | |
1036 | ||
7be98234 RW |
1037 | if (swsusp_page_is_forbidden(page) && |
1038 | swsusp_page_is_free(page)) { | |
1039 | swsusp_unset_page_forbidden(page); | |
1040 | swsusp_unset_page_free(page); | |
8357376d | 1041 | __free_page(page); |
25761b6e RW |
1042 | } |
1043 | } | |
1044 | } | |
f577eb30 RW |
1045 | nr_copy_pages = 0; |
1046 | nr_meta_pages = 0; | |
75534b50 | 1047 | restore_pblist = NULL; |
6e1819d6 | 1048 | buffer = NULL; |
25761b6e RW |
1049 | } |
1050 | ||
8357376d RW |
1051 | #ifdef CONFIG_HIGHMEM |
1052 | /** | |
1053 | * count_pages_for_highmem - compute the number of non-highmem pages | |
1054 | * that will be necessary for creating copies of highmem pages. | |
1055 | */ | |
1056 | ||
1057 | static unsigned int count_pages_for_highmem(unsigned int nr_highmem) | |
1058 | { | |
1059 | unsigned int free_highmem = count_free_highmem_pages(); | |
1060 | ||
1061 | if (free_highmem >= nr_highmem) | |
1062 | nr_highmem = 0; | |
1063 | else | |
1064 | nr_highmem -= free_highmem; | |
1065 | ||
1066 | return nr_highmem; | |
1067 | } | |
1068 | #else | |
1069 | static unsigned int | |
1070 | count_pages_for_highmem(unsigned int nr_highmem) { return 0; } | |
1071 | #endif /* CONFIG_HIGHMEM */ | |
25761b6e RW |
1072 | |
1073 | /** | |
8357376d RW |
1074 | * enough_free_mem - Make sure we have enough free memory for the |
1075 | * snapshot image. | |
25761b6e RW |
1076 | */ |
1077 | ||
8357376d | 1078 | static int enough_free_mem(unsigned int nr_pages, unsigned int nr_highmem) |
25761b6e | 1079 | { |
e5e2fa78 | 1080 | struct zone *zone; |
940864dd | 1081 | unsigned int free = 0, meta = 0; |
e5e2fa78 | 1082 | |
8357376d RW |
1083 | for_each_zone(zone) { |
1084 | meta += snapshot_additional_pages(zone); | |
1085 | if (!is_highmem(zone)) | |
d23ad423 | 1086 | free += zone_page_state(zone, NR_FREE_PAGES); |
8357376d | 1087 | } |
940864dd | 1088 | |
8357376d RW |
1089 | nr_pages += count_pages_for_highmem(nr_highmem); |
1090 | pr_debug("swsusp: Normal pages needed: %u + %u + %u, available pages: %u\n", | |
940864dd RW |
1091 | nr_pages, PAGES_FOR_IO, meta, free); |
1092 | ||
1093 | return free > nr_pages + PAGES_FOR_IO + meta; | |
25761b6e RW |
1094 | } |
1095 | ||
8357376d RW |
1096 | #ifdef CONFIG_HIGHMEM |
1097 | /** | |
1098 | * get_highmem_buffer - if there are some highmem pages in the suspend | |
1099 | * image, we may need the buffer to copy them and/or load their data. | |
1100 | */ | |
1101 | ||
1102 | static inline int get_highmem_buffer(int safe_needed) | |
1103 | { | |
1104 | buffer = get_image_page(GFP_ATOMIC | __GFP_COLD, safe_needed); | |
1105 | return buffer ? 0 : -ENOMEM; | |
1106 | } | |
1107 | ||
1108 | /** | |
1109 | * alloc_highmem_image_pages - allocate some highmem pages for the image. | |
1110 | * Try to allocate as many pages as needed, but if the number of free | |
1111 | * highmem pages is lesser than that, allocate them all. | |
1112 | */ | |
1113 | ||
1114 | static inline unsigned int | |
1115 | alloc_highmem_image_pages(struct memory_bitmap *bm, unsigned int nr_highmem) | |
1116 | { | |
1117 | unsigned int to_alloc = count_free_highmem_pages(); | |
1118 | ||
1119 | if (to_alloc > nr_highmem) | |
1120 | to_alloc = nr_highmem; | |
1121 | ||
1122 | nr_highmem -= to_alloc; | |
1123 | while (to_alloc-- > 0) { | |
1124 | struct page *page; | |
1125 | ||
1126 | page = alloc_image_page(__GFP_HIGHMEM); | |
1127 | memory_bm_set_bit(bm, page_to_pfn(page)); | |
1128 | } | |
1129 | return nr_highmem; | |
1130 | } | |
1131 | #else | |
1132 | static inline int get_highmem_buffer(int safe_needed) { return 0; } | |
1133 | ||
1134 | static inline unsigned int | |
1135 | alloc_highmem_image_pages(struct memory_bitmap *bm, unsigned int n) { return 0; } | |
1136 | #endif /* CONFIG_HIGHMEM */ | |
1137 | ||
1138 | /** | |
1139 | * swsusp_alloc - allocate memory for the suspend image | |
1140 | * | |
1141 | * We first try to allocate as many highmem pages as there are | |
1142 | * saveable highmem pages in the system. If that fails, we allocate | |
1143 | * non-highmem pages for the copies of the remaining highmem ones. | |
1144 | * | |
1145 | * In this approach it is likely that the copies of highmem pages will | |
1146 | * also be located in the high memory, because of the way in which | |
1147 | * copy_data_pages() works. | |
1148 | */ | |
1149 | ||
b788db79 RW |
1150 | static int |
1151 | swsusp_alloc(struct memory_bitmap *orig_bm, struct memory_bitmap *copy_bm, | |
8357376d | 1152 | unsigned int nr_pages, unsigned int nr_highmem) |
054bd4c1 | 1153 | { |
b788db79 | 1154 | int error; |
054bd4c1 | 1155 | |
b788db79 RW |
1156 | error = memory_bm_create(orig_bm, GFP_ATOMIC | __GFP_COLD, PG_ANY); |
1157 | if (error) | |
1158 | goto Free; | |
25761b6e | 1159 | |
b788db79 RW |
1160 | error = memory_bm_create(copy_bm, GFP_ATOMIC | __GFP_COLD, PG_ANY); |
1161 | if (error) | |
1162 | goto Free; | |
25761b6e | 1163 | |
8357376d RW |
1164 | if (nr_highmem > 0) { |
1165 | error = get_highmem_buffer(PG_ANY); | |
1166 | if (error) | |
1167 | goto Free; | |
1168 | ||
1169 | nr_pages += alloc_highmem_image_pages(copy_bm, nr_highmem); | |
1170 | } | |
b788db79 | 1171 | while (nr_pages-- > 0) { |
8357376d RW |
1172 | struct page *page = alloc_image_page(GFP_ATOMIC | __GFP_COLD); |
1173 | ||
b788db79 RW |
1174 | if (!page) |
1175 | goto Free; | |
25761b6e | 1176 | |
b788db79 | 1177 | memory_bm_set_bit(copy_bm, page_to_pfn(page)); |
25761b6e | 1178 | } |
b788db79 | 1179 | return 0; |
25761b6e | 1180 | |
59a49335 | 1181 | Free: |
b788db79 RW |
1182 | swsusp_free(); |
1183 | return -ENOMEM; | |
25761b6e RW |
1184 | } |
1185 | ||
8357376d RW |
1186 | /* Memory bitmap used for marking saveable pages (during suspend) or the |
1187 | * suspend image pages (during resume) | |
1188 | */ | |
b788db79 | 1189 | static struct memory_bitmap orig_bm; |
8357376d RW |
1190 | /* Memory bitmap used on suspend for marking allocated pages that will contain |
1191 | * the copies of saveable pages. During resume it is initially used for | |
1192 | * marking the suspend image pages, but then its set bits are duplicated in | |
1193 | * @orig_bm and it is released. Next, on systems with high memory, it may be | |
1194 | * used for marking "safe" highmem pages, but it has to be reinitialized for | |
1195 | * this purpose. | |
b788db79 RW |
1196 | */ |
1197 | static struct memory_bitmap copy_bm; | |
1198 | ||
2e32a43e | 1199 | asmlinkage int swsusp_save(void) |
25761b6e | 1200 | { |
8357376d | 1201 | unsigned int nr_pages, nr_highmem; |
25761b6e | 1202 | |
8357376d | 1203 | printk("swsusp: critical section: \n"); |
25761b6e RW |
1204 | |
1205 | drain_local_pages(); | |
a0f49651 | 1206 | nr_pages = count_data_pages(); |
8357376d RW |
1207 | nr_highmem = count_highmem_pages(); |
1208 | printk("swsusp: Need to copy %u pages\n", nr_pages + nr_highmem); | |
25761b6e | 1209 | |
8357376d | 1210 | if (!enough_free_mem(nr_pages, nr_highmem)) { |
25761b6e RW |
1211 | printk(KERN_ERR "swsusp: Not enough free memory\n"); |
1212 | return -ENOMEM; | |
1213 | } | |
1214 | ||
8357376d RW |
1215 | if (swsusp_alloc(&orig_bm, ©_bm, nr_pages, nr_highmem)) { |
1216 | printk(KERN_ERR "swsusp: Memory allocation failed\n"); | |
a0f49651 | 1217 | return -ENOMEM; |
8357376d | 1218 | } |
25761b6e RW |
1219 | |
1220 | /* During allocating of suspend pagedir, new cold pages may appear. | |
1221 | * Kill them. | |
1222 | */ | |
1223 | drain_local_pages(); | |
b788db79 | 1224 | copy_data_pages(©_bm, &orig_bm); |
25761b6e RW |
1225 | |
1226 | /* | |
1227 | * End of critical section. From now on, we can write to memory, | |
1228 | * but we should not touch disk. This specially means we must _not_ | |
1229 | * touch swap space! Except we must write out our image of course. | |
1230 | */ | |
1231 | ||
8357376d | 1232 | nr_pages += nr_highmem; |
a0f49651 | 1233 | nr_copy_pages = nr_pages; |
8357376d | 1234 | nr_meta_pages = DIV_ROUND_UP(nr_pages * sizeof(long), PAGE_SIZE); |
a0f49651 | 1235 | |
d60846c4 | 1236 | printk("swsusp: critical section: done (%d pages copied)\n", nr_pages); |
8357376d | 1237 | |
25761b6e RW |
1238 | return 0; |
1239 | } | |
f577eb30 RW |
1240 | |
1241 | static void init_header(struct swsusp_info *info) | |
1242 | { | |
1243 | memset(info, 0, sizeof(struct swsusp_info)); | |
1244 | info->version_code = LINUX_VERSION_CODE; | |
1245 | info->num_physpages = num_physpages; | |
96b644bd | 1246 | memcpy(&info->uts, init_utsname(), sizeof(struct new_utsname)); |
f577eb30 RW |
1247 | info->cpus = num_online_cpus(); |
1248 | info->image_pages = nr_copy_pages; | |
1249 | info->pages = nr_copy_pages + nr_meta_pages + 1; | |
6e1819d6 RW |
1250 | info->size = info->pages; |
1251 | info->size <<= PAGE_SHIFT; | |
f577eb30 RW |
1252 | } |
1253 | ||
1254 | /** | |
940864dd RW |
1255 | * pack_pfns - pfns corresponding to the set bits found in the bitmap @bm |
1256 | * are stored in the array @buf[] (1 page at a time) | |
f577eb30 RW |
1257 | */ |
1258 | ||
b788db79 | 1259 | static inline void |
940864dd | 1260 | pack_pfns(unsigned long *buf, struct memory_bitmap *bm) |
f577eb30 RW |
1261 | { |
1262 | int j; | |
1263 | ||
b788db79 | 1264 | for (j = 0; j < PAGE_SIZE / sizeof(long); j++) { |
940864dd RW |
1265 | buf[j] = memory_bm_next_pfn(bm); |
1266 | if (unlikely(buf[j] == BM_END_OF_MAP)) | |
b788db79 | 1267 | break; |
f577eb30 | 1268 | } |
f577eb30 RW |
1269 | } |
1270 | ||
1271 | /** | |
1272 | * snapshot_read_next - used for reading the system memory snapshot. | |
1273 | * | |
1274 | * On the first call to it @handle should point to a zeroed | |
1275 | * snapshot_handle structure. The structure gets updated and a pointer | |
1276 | * to it should be passed to this function every next time. | |
1277 | * | |
1278 | * The @count parameter should contain the number of bytes the caller | |
1279 | * wants to read from the snapshot. It must not be zero. | |
1280 | * | |
1281 | * On success the function returns a positive number. Then, the caller | |
1282 | * is allowed to read up to the returned number of bytes from the memory | |
1283 | * location computed by the data_of() macro. The number returned | |
1284 | * may be smaller than @count, but this only happens if the read would | |
1285 | * cross a page boundary otherwise. | |
1286 | * | |
1287 | * The function returns 0 to indicate the end of data stream condition, | |
1288 | * and a negative number is returned on error. In such cases the | |
1289 | * structure pointed to by @handle is not updated and should not be used | |
1290 | * any more. | |
1291 | */ | |
1292 | ||
1293 | int snapshot_read_next(struct snapshot_handle *handle, size_t count) | |
1294 | { | |
fb13a28b | 1295 | if (handle->cur > nr_meta_pages + nr_copy_pages) |
f577eb30 | 1296 | return 0; |
b788db79 | 1297 | |
f577eb30 RW |
1298 | if (!buffer) { |
1299 | /* This makes the buffer be freed by swsusp_free() */ | |
8357376d | 1300 | buffer = get_image_page(GFP_ATOMIC, PG_ANY); |
f577eb30 RW |
1301 | if (!buffer) |
1302 | return -ENOMEM; | |
1303 | } | |
1304 | if (!handle->offset) { | |
1305 | init_header((struct swsusp_info *)buffer); | |
1306 | handle->buffer = buffer; | |
b788db79 RW |
1307 | memory_bm_position_reset(&orig_bm); |
1308 | memory_bm_position_reset(©_bm); | |
f577eb30 | 1309 | } |
fb13a28b RW |
1310 | if (handle->prev < handle->cur) { |
1311 | if (handle->cur <= nr_meta_pages) { | |
b788db79 | 1312 | memset(buffer, 0, PAGE_SIZE); |
940864dd | 1313 | pack_pfns(buffer, &orig_bm); |
f577eb30 | 1314 | } else { |
8357376d | 1315 | struct page *page; |
b788db79 | 1316 | |
8357376d RW |
1317 | page = pfn_to_page(memory_bm_next_pfn(©_bm)); |
1318 | if (PageHighMem(page)) { | |
1319 | /* Highmem pages are copied to the buffer, | |
1320 | * because we can't return with a kmapped | |
1321 | * highmem page (we may not be called again). | |
1322 | */ | |
1323 | void *kaddr; | |
1324 | ||
1325 | kaddr = kmap_atomic(page, KM_USER0); | |
1326 | memcpy(buffer, kaddr, PAGE_SIZE); | |
1327 | kunmap_atomic(kaddr, KM_USER0); | |
1328 | handle->buffer = buffer; | |
1329 | } else { | |
1330 | handle->buffer = page_address(page); | |
1331 | } | |
f577eb30 | 1332 | } |
fb13a28b | 1333 | handle->prev = handle->cur; |
f577eb30 | 1334 | } |
fb13a28b RW |
1335 | handle->buf_offset = handle->cur_offset; |
1336 | if (handle->cur_offset + count >= PAGE_SIZE) { | |
1337 | count = PAGE_SIZE - handle->cur_offset; | |
1338 | handle->cur_offset = 0; | |
1339 | handle->cur++; | |
f577eb30 | 1340 | } else { |
fb13a28b | 1341 | handle->cur_offset += count; |
f577eb30 RW |
1342 | } |
1343 | handle->offset += count; | |
1344 | return count; | |
1345 | } | |
1346 | ||
1347 | /** | |
1348 | * mark_unsafe_pages - mark the pages that cannot be used for storing | |
1349 | * the image during resume, because they conflict with the pages that | |
1350 | * had been used before suspend | |
1351 | */ | |
1352 | ||
940864dd | 1353 | static int mark_unsafe_pages(struct memory_bitmap *bm) |
f577eb30 RW |
1354 | { |
1355 | struct zone *zone; | |
ae83c5ee | 1356 | unsigned long pfn, max_zone_pfn; |
f577eb30 RW |
1357 | |
1358 | /* Clear page flags */ | |
8357376d | 1359 | for_each_zone(zone) { |
ae83c5ee RW |
1360 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
1361 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
1362 | if (pfn_valid(pfn)) | |
7be98234 | 1363 | swsusp_unset_page_free(pfn_to_page(pfn)); |
f577eb30 RW |
1364 | } |
1365 | ||
940864dd RW |
1366 | /* Mark pages that correspond to the "original" pfns as "unsafe" */ |
1367 | memory_bm_position_reset(bm); | |
1368 | do { | |
1369 | pfn = memory_bm_next_pfn(bm); | |
1370 | if (likely(pfn != BM_END_OF_MAP)) { | |
1371 | if (likely(pfn_valid(pfn))) | |
7be98234 | 1372 | swsusp_set_page_free(pfn_to_page(pfn)); |
940864dd RW |
1373 | else |
1374 | return -EFAULT; | |
1375 | } | |
1376 | } while (pfn != BM_END_OF_MAP); | |
f577eb30 | 1377 | |
940864dd | 1378 | allocated_unsafe_pages = 0; |
968808b8 | 1379 | |
f577eb30 RW |
1380 | return 0; |
1381 | } | |
1382 | ||
940864dd RW |
1383 | static void |
1384 | duplicate_memory_bitmap(struct memory_bitmap *dst, struct memory_bitmap *src) | |
f577eb30 | 1385 | { |
940864dd RW |
1386 | unsigned long pfn; |
1387 | ||
1388 | memory_bm_position_reset(src); | |
1389 | pfn = memory_bm_next_pfn(src); | |
1390 | while (pfn != BM_END_OF_MAP) { | |
1391 | memory_bm_set_bit(dst, pfn); | |
1392 | pfn = memory_bm_next_pfn(src); | |
f577eb30 RW |
1393 | } |
1394 | } | |
1395 | ||
940864dd | 1396 | static inline int check_header(struct swsusp_info *info) |
f577eb30 RW |
1397 | { |
1398 | char *reason = NULL; | |
1399 | ||
1400 | if (info->version_code != LINUX_VERSION_CODE) | |
1401 | reason = "kernel version"; | |
1402 | if (info->num_physpages != num_physpages) | |
1403 | reason = "memory size"; | |
96b644bd | 1404 | if (strcmp(info->uts.sysname,init_utsname()->sysname)) |
f577eb30 | 1405 | reason = "system type"; |
96b644bd | 1406 | if (strcmp(info->uts.release,init_utsname()->release)) |
f577eb30 | 1407 | reason = "kernel release"; |
96b644bd | 1408 | if (strcmp(info->uts.version,init_utsname()->version)) |
f577eb30 | 1409 | reason = "version"; |
96b644bd | 1410 | if (strcmp(info->uts.machine,init_utsname()->machine)) |
f577eb30 RW |
1411 | reason = "machine"; |
1412 | if (reason) { | |
1413 | printk(KERN_ERR "swsusp: Resume mismatch: %s\n", reason); | |
1414 | return -EPERM; | |
1415 | } | |
1416 | return 0; | |
1417 | } | |
1418 | ||
1419 | /** | |
1420 | * load header - check the image header and copy data from it | |
1421 | */ | |
1422 | ||
940864dd RW |
1423 | static int |
1424 | load_header(struct swsusp_info *info) | |
f577eb30 RW |
1425 | { |
1426 | int error; | |
f577eb30 | 1427 | |
940864dd | 1428 | restore_pblist = NULL; |
f577eb30 RW |
1429 | error = check_header(info); |
1430 | if (!error) { | |
f577eb30 RW |
1431 | nr_copy_pages = info->image_pages; |
1432 | nr_meta_pages = info->pages - info->image_pages - 1; | |
1433 | } | |
1434 | return error; | |
1435 | } | |
1436 | ||
1437 | /** | |
940864dd RW |
1438 | * unpack_orig_pfns - for each element of @buf[] (1 page at a time) set |
1439 | * the corresponding bit in the memory bitmap @bm | |
f577eb30 RW |
1440 | */ |
1441 | ||
940864dd RW |
1442 | static inline void |
1443 | unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm) | |
f577eb30 RW |
1444 | { |
1445 | int j; | |
1446 | ||
940864dd RW |
1447 | for (j = 0; j < PAGE_SIZE / sizeof(long); j++) { |
1448 | if (unlikely(buf[j] == BM_END_OF_MAP)) | |
1449 | break; | |
1450 | ||
1451 | memory_bm_set_bit(bm, buf[j]); | |
f577eb30 | 1452 | } |
f577eb30 RW |
1453 | } |
1454 | ||
8357376d RW |
1455 | /* List of "safe" pages that may be used to store data loaded from the suspend |
1456 | * image | |
1457 | */ | |
1458 | static struct linked_page *safe_pages_list; | |
1459 | ||
1460 | #ifdef CONFIG_HIGHMEM | |
1461 | /* struct highmem_pbe is used for creating the list of highmem pages that | |
1462 | * should be restored atomically during the resume from disk, because the page | |
1463 | * frames they have occupied before the suspend are in use. | |
1464 | */ | |
1465 | struct highmem_pbe { | |
1466 | struct page *copy_page; /* data is here now */ | |
1467 | struct page *orig_page; /* data was here before the suspend */ | |
1468 | struct highmem_pbe *next; | |
1469 | }; | |
1470 | ||
1471 | /* List of highmem PBEs needed for restoring the highmem pages that were | |
1472 | * allocated before the suspend and included in the suspend image, but have | |
1473 | * also been allocated by the "resume" kernel, so their contents cannot be | |
1474 | * written directly to their "original" page frames. | |
1475 | */ | |
1476 | static struct highmem_pbe *highmem_pblist; | |
1477 | ||
1478 | /** | |
1479 | * count_highmem_image_pages - compute the number of highmem pages in the | |
1480 | * suspend image. The bits in the memory bitmap @bm that correspond to the | |
1481 | * image pages are assumed to be set. | |
1482 | */ | |
1483 | ||
1484 | static unsigned int count_highmem_image_pages(struct memory_bitmap *bm) | |
1485 | { | |
1486 | unsigned long pfn; | |
1487 | unsigned int cnt = 0; | |
1488 | ||
1489 | memory_bm_position_reset(bm); | |
1490 | pfn = memory_bm_next_pfn(bm); | |
1491 | while (pfn != BM_END_OF_MAP) { | |
1492 | if (PageHighMem(pfn_to_page(pfn))) | |
1493 | cnt++; | |
1494 | ||
1495 | pfn = memory_bm_next_pfn(bm); | |
1496 | } | |
1497 | return cnt; | |
1498 | } | |
1499 | ||
1500 | /** | |
1501 | * prepare_highmem_image - try to allocate as many highmem pages as | |
1502 | * there are highmem image pages (@nr_highmem_p points to the variable | |
1503 | * containing the number of highmem image pages). The pages that are | |
1504 | * "safe" (ie. will not be overwritten when the suspend image is | |
1505 | * restored) have the corresponding bits set in @bm (it must be | |
1506 | * unitialized). | |
1507 | * | |
1508 | * NOTE: This function should not be called if there are no highmem | |
1509 | * image pages. | |
1510 | */ | |
1511 | ||
1512 | static unsigned int safe_highmem_pages; | |
1513 | ||
1514 | static struct memory_bitmap *safe_highmem_bm; | |
1515 | ||
1516 | static int | |
1517 | prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p) | |
1518 | { | |
1519 | unsigned int to_alloc; | |
1520 | ||
1521 | if (memory_bm_create(bm, GFP_ATOMIC, PG_SAFE)) | |
1522 | return -ENOMEM; | |
1523 | ||
1524 | if (get_highmem_buffer(PG_SAFE)) | |
1525 | return -ENOMEM; | |
1526 | ||
1527 | to_alloc = count_free_highmem_pages(); | |
1528 | if (to_alloc > *nr_highmem_p) | |
1529 | to_alloc = *nr_highmem_p; | |
1530 | else | |
1531 | *nr_highmem_p = to_alloc; | |
1532 | ||
1533 | safe_highmem_pages = 0; | |
1534 | while (to_alloc-- > 0) { | |
1535 | struct page *page; | |
1536 | ||
1537 | page = alloc_page(__GFP_HIGHMEM); | |
7be98234 | 1538 | if (!swsusp_page_is_free(page)) { |
8357376d RW |
1539 | /* The page is "safe", set its bit the bitmap */ |
1540 | memory_bm_set_bit(bm, page_to_pfn(page)); | |
1541 | safe_highmem_pages++; | |
1542 | } | |
1543 | /* Mark the page as allocated */ | |
7be98234 RW |
1544 | swsusp_set_page_forbidden(page); |
1545 | swsusp_set_page_free(page); | |
8357376d RW |
1546 | } |
1547 | memory_bm_position_reset(bm); | |
1548 | safe_highmem_bm = bm; | |
1549 | return 0; | |
1550 | } | |
1551 | ||
1552 | /** | |
1553 | * get_highmem_page_buffer - for given highmem image page find the buffer | |
1554 | * that suspend_write_next() should set for its caller to write to. | |
1555 | * | |
1556 | * If the page is to be saved to its "original" page frame or a copy of | |
1557 | * the page is to be made in the highmem, @buffer is returned. Otherwise, | |
1558 | * the copy of the page is to be made in normal memory, so the address of | |
1559 | * the copy is returned. | |
1560 | * | |
1561 | * If @buffer is returned, the caller of suspend_write_next() will write | |
1562 | * the page's contents to @buffer, so they will have to be copied to the | |
1563 | * right location on the next call to suspend_write_next() and it is done | |
1564 | * with the help of copy_last_highmem_page(). For this purpose, if | |
1565 | * @buffer is returned, @last_highmem page is set to the page to which | |
1566 | * the data will have to be copied from @buffer. | |
1567 | */ | |
1568 | ||
1569 | static struct page *last_highmem_page; | |
1570 | ||
1571 | static void * | |
1572 | get_highmem_page_buffer(struct page *page, struct chain_allocator *ca) | |
1573 | { | |
1574 | struct highmem_pbe *pbe; | |
1575 | void *kaddr; | |
1576 | ||
7be98234 | 1577 | if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page)) { |
8357376d RW |
1578 | /* We have allocated the "original" page frame and we can |
1579 | * use it directly to store the loaded page. | |
1580 | */ | |
1581 | last_highmem_page = page; | |
1582 | return buffer; | |
1583 | } | |
1584 | /* The "original" page frame has not been allocated and we have to | |
1585 | * use a "safe" page frame to store the loaded page. | |
1586 | */ | |
1587 | pbe = chain_alloc(ca, sizeof(struct highmem_pbe)); | |
1588 | if (!pbe) { | |
1589 | swsusp_free(); | |
1590 | return NULL; | |
1591 | } | |
1592 | pbe->orig_page = page; | |
1593 | if (safe_highmem_pages > 0) { | |
1594 | struct page *tmp; | |
1595 | ||
1596 | /* Copy of the page will be stored in high memory */ | |
1597 | kaddr = buffer; | |
1598 | tmp = pfn_to_page(memory_bm_next_pfn(safe_highmem_bm)); | |
1599 | safe_highmem_pages--; | |
1600 | last_highmem_page = tmp; | |
1601 | pbe->copy_page = tmp; | |
1602 | } else { | |
1603 | /* Copy of the page will be stored in normal memory */ | |
1604 | kaddr = safe_pages_list; | |
1605 | safe_pages_list = safe_pages_list->next; | |
1606 | pbe->copy_page = virt_to_page(kaddr); | |
1607 | } | |
1608 | pbe->next = highmem_pblist; | |
1609 | highmem_pblist = pbe; | |
1610 | return kaddr; | |
1611 | } | |
1612 | ||
1613 | /** | |
1614 | * copy_last_highmem_page - copy the contents of a highmem image from | |
1615 | * @buffer, where the caller of snapshot_write_next() has place them, | |
1616 | * to the right location represented by @last_highmem_page . | |
1617 | */ | |
1618 | ||
1619 | static void copy_last_highmem_page(void) | |
1620 | { | |
1621 | if (last_highmem_page) { | |
1622 | void *dst; | |
1623 | ||
1624 | dst = kmap_atomic(last_highmem_page, KM_USER0); | |
1625 | memcpy(dst, buffer, PAGE_SIZE); | |
1626 | kunmap_atomic(dst, KM_USER0); | |
1627 | last_highmem_page = NULL; | |
1628 | } | |
1629 | } | |
1630 | ||
1631 | static inline int last_highmem_page_copied(void) | |
1632 | { | |
1633 | return !last_highmem_page; | |
1634 | } | |
1635 | ||
1636 | static inline void free_highmem_data(void) | |
1637 | { | |
1638 | if (safe_highmem_bm) | |
1639 | memory_bm_free(safe_highmem_bm, PG_UNSAFE_CLEAR); | |
1640 | ||
1641 | if (buffer) | |
1642 | free_image_page(buffer, PG_UNSAFE_CLEAR); | |
1643 | } | |
1644 | #else | |
1645 | static inline int get_safe_write_buffer(void) { return 0; } | |
1646 | ||
1647 | static unsigned int | |
1648 | count_highmem_image_pages(struct memory_bitmap *bm) { return 0; } | |
1649 | ||
1650 | static inline int | |
1651 | prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p) | |
1652 | { | |
1653 | return 0; | |
1654 | } | |
1655 | ||
1656 | static inline void * | |
1657 | get_highmem_page_buffer(struct page *page, struct chain_allocator *ca) | |
1658 | { | |
1659 | return NULL; | |
1660 | } | |
1661 | ||
1662 | static inline void copy_last_highmem_page(void) {} | |
1663 | static inline int last_highmem_page_copied(void) { return 1; } | |
1664 | static inline void free_highmem_data(void) {} | |
1665 | #endif /* CONFIG_HIGHMEM */ | |
1666 | ||
f577eb30 | 1667 | /** |
940864dd RW |
1668 | * prepare_image - use the memory bitmap @bm to mark the pages that will |
1669 | * be overwritten in the process of restoring the system memory state | |
1670 | * from the suspend image ("unsafe" pages) and allocate memory for the | |
1671 | * image. | |
968808b8 | 1672 | * |
940864dd RW |
1673 | * The idea is to allocate a new memory bitmap first and then allocate |
1674 | * as many pages as needed for the image data, but not to assign these | |
1675 | * pages to specific tasks initially. Instead, we just mark them as | |
8357376d RW |
1676 | * allocated and create a lists of "safe" pages that will be used |
1677 | * later. On systems with high memory a list of "safe" highmem pages is | |
1678 | * also created. | |
f577eb30 RW |
1679 | */ |
1680 | ||
940864dd RW |
1681 | #define PBES_PER_LINKED_PAGE (LINKED_PAGE_DATA_SIZE / sizeof(struct pbe)) |
1682 | ||
940864dd RW |
1683 | static int |
1684 | prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm) | |
f577eb30 | 1685 | { |
8357376d | 1686 | unsigned int nr_pages, nr_highmem; |
940864dd RW |
1687 | struct linked_page *sp_list, *lp; |
1688 | int error; | |
f577eb30 | 1689 | |
8357376d RW |
1690 | /* If there is no highmem, the buffer will not be necessary */ |
1691 | free_image_page(buffer, PG_UNSAFE_CLEAR); | |
1692 | buffer = NULL; | |
1693 | ||
1694 | nr_highmem = count_highmem_image_pages(bm); | |
940864dd RW |
1695 | error = mark_unsafe_pages(bm); |
1696 | if (error) | |
1697 | goto Free; | |
1698 | ||
1699 | error = memory_bm_create(new_bm, GFP_ATOMIC, PG_SAFE); | |
1700 | if (error) | |
1701 | goto Free; | |
1702 | ||
1703 | duplicate_memory_bitmap(new_bm, bm); | |
1704 | memory_bm_free(bm, PG_UNSAFE_KEEP); | |
8357376d RW |
1705 | if (nr_highmem > 0) { |
1706 | error = prepare_highmem_image(bm, &nr_highmem); | |
1707 | if (error) | |
1708 | goto Free; | |
1709 | } | |
940864dd RW |
1710 | /* Reserve some safe pages for potential later use. |
1711 | * | |
1712 | * NOTE: This way we make sure there will be enough safe pages for the | |
1713 | * chain_alloc() in get_buffer(). It is a bit wasteful, but | |
1714 | * nr_copy_pages cannot be greater than 50% of the memory anyway. | |
1715 | */ | |
1716 | sp_list = NULL; | |
1717 | /* nr_copy_pages cannot be lesser than allocated_unsafe_pages */ | |
8357376d | 1718 | nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages; |
940864dd RW |
1719 | nr_pages = DIV_ROUND_UP(nr_pages, PBES_PER_LINKED_PAGE); |
1720 | while (nr_pages > 0) { | |
8357376d | 1721 | lp = get_image_page(GFP_ATOMIC, PG_SAFE); |
940864dd | 1722 | if (!lp) { |
f577eb30 | 1723 | error = -ENOMEM; |
940864dd RW |
1724 | goto Free; |
1725 | } | |
1726 | lp->next = sp_list; | |
1727 | sp_list = lp; | |
1728 | nr_pages--; | |
f577eb30 | 1729 | } |
940864dd RW |
1730 | /* Preallocate memory for the image */ |
1731 | safe_pages_list = NULL; | |
8357376d | 1732 | nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages; |
940864dd RW |
1733 | while (nr_pages > 0) { |
1734 | lp = (struct linked_page *)get_zeroed_page(GFP_ATOMIC); | |
1735 | if (!lp) { | |
1736 | error = -ENOMEM; | |
1737 | goto Free; | |
1738 | } | |
7be98234 | 1739 | if (!swsusp_page_is_free(virt_to_page(lp))) { |
940864dd RW |
1740 | /* The page is "safe", add it to the list */ |
1741 | lp->next = safe_pages_list; | |
1742 | safe_pages_list = lp; | |
968808b8 | 1743 | } |
940864dd | 1744 | /* Mark the page as allocated */ |
7be98234 RW |
1745 | swsusp_set_page_forbidden(virt_to_page(lp)); |
1746 | swsusp_set_page_free(virt_to_page(lp)); | |
940864dd | 1747 | nr_pages--; |
968808b8 | 1748 | } |
940864dd RW |
1749 | /* Free the reserved safe pages so that chain_alloc() can use them */ |
1750 | while (sp_list) { | |
1751 | lp = sp_list->next; | |
1752 | free_image_page(sp_list, PG_UNSAFE_CLEAR); | |
1753 | sp_list = lp; | |
f577eb30 | 1754 | } |
940864dd RW |
1755 | return 0; |
1756 | ||
59a49335 | 1757 | Free: |
940864dd | 1758 | swsusp_free(); |
f577eb30 RW |
1759 | return error; |
1760 | } | |
1761 | ||
940864dd RW |
1762 | /** |
1763 | * get_buffer - compute the address that snapshot_write_next() should | |
1764 | * set for its caller to write to. | |
1765 | */ | |
1766 | ||
1767 | static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca) | |
968808b8 | 1768 | { |
940864dd RW |
1769 | struct pbe *pbe; |
1770 | struct page *page = pfn_to_page(memory_bm_next_pfn(bm)); | |
968808b8 | 1771 | |
8357376d RW |
1772 | if (PageHighMem(page)) |
1773 | return get_highmem_page_buffer(page, ca); | |
1774 | ||
7be98234 | 1775 | if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page)) |
940864dd RW |
1776 | /* We have allocated the "original" page frame and we can |
1777 | * use it directly to store the loaded page. | |
968808b8 | 1778 | */ |
940864dd RW |
1779 | return page_address(page); |
1780 | ||
1781 | /* The "original" page frame has not been allocated and we have to | |
1782 | * use a "safe" page frame to store the loaded page. | |
968808b8 | 1783 | */ |
940864dd RW |
1784 | pbe = chain_alloc(ca, sizeof(struct pbe)); |
1785 | if (!pbe) { | |
1786 | swsusp_free(); | |
1787 | return NULL; | |
1788 | } | |
8357376d RW |
1789 | pbe->orig_address = page_address(page); |
1790 | pbe->address = safe_pages_list; | |
940864dd RW |
1791 | safe_pages_list = safe_pages_list->next; |
1792 | pbe->next = restore_pblist; | |
1793 | restore_pblist = pbe; | |
8357376d | 1794 | return pbe->address; |
968808b8 RW |
1795 | } |
1796 | ||
f577eb30 RW |
1797 | /** |
1798 | * snapshot_write_next - used for writing the system memory snapshot. | |
1799 | * | |
1800 | * On the first call to it @handle should point to a zeroed | |
1801 | * snapshot_handle structure. The structure gets updated and a pointer | |
1802 | * to it should be passed to this function every next time. | |
1803 | * | |
1804 | * The @count parameter should contain the number of bytes the caller | |
1805 | * wants to write to the image. It must not be zero. | |
1806 | * | |
1807 | * On success the function returns a positive number. Then, the caller | |
1808 | * is allowed to write up to the returned number of bytes to the memory | |
1809 | * location computed by the data_of() macro. The number returned | |
1810 | * may be smaller than @count, but this only happens if the write would | |
1811 | * cross a page boundary otherwise. | |
1812 | * | |
1813 | * The function returns 0 to indicate the "end of file" condition, | |
1814 | * and a negative number is returned on error. In such cases the | |
1815 | * structure pointed to by @handle is not updated and should not be used | |
1816 | * any more. | |
1817 | */ | |
1818 | ||
1819 | int snapshot_write_next(struct snapshot_handle *handle, size_t count) | |
1820 | { | |
940864dd | 1821 | static struct chain_allocator ca; |
f577eb30 RW |
1822 | int error = 0; |
1823 | ||
940864dd | 1824 | /* Check if we have already loaded the entire image */ |
fb13a28b | 1825 | if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages) |
f577eb30 | 1826 | return 0; |
940864dd | 1827 | |
8357376d RW |
1828 | if (handle->offset == 0) { |
1829 | if (!buffer) | |
1830 | /* This makes the buffer be freed by swsusp_free() */ | |
1831 | buffer = get_image_page(GFP_ATOMIC, PG_ANY); | |
1832 | ||
f577eb30 RW |
1833 | if (!buffer) |
1834 | return -ENOMEM; | |
8357376d | 1835 | |
f577eb30 | 1836 | handle->buffer = buffer; |
8357376d | 1837 | } |
546e0d27 | 1838 | handle->sync_read = 1; |
fb13a28b | 1839 | if (handle->prev < handle->cur) { |
940864dd RW |
1840 | if (handle->prev == 0) { |
1841 | error = load_header(buffer); | |
1842 | if (error) | |
1843 | return error; | |
1844 | ||
1845 | error = memory_bm_create(©_bm, GFP_ATOMIC, PG_ANY); | |
f577eb30 RW |
1846 | if (error) |
1847 | return error; | |
940864dd | 1848 | |
f577eb30 | 1849 | } else if (handle->prev <= nr_meta_pages) { |
940864dd RW |
1850 | unpack_orig_pfns(buffer, ©_bm); |
1851 | if (handle->prev == nr_meta_pages) { | |
1852 | error = prepare_image(&orig_bm, ©_bm); | |
f577eb30 RW |
1853 | if (error) |
1854 | return error; | |
940864dd RW |
1855 | |
1856 | chain_init(&ca, GFP_ATOMIC, PG_SAFE); | |
1857 | memory_bm_position_reset(&orig_bm); | |
1858 | restore_pblist = NULL; | |
1859 | handle->buffer = get_buffer(&orig_bm, &ca); | |
546e0d27 | 1860 | handle->sync_read = 0; |
940864dd RW |
1861 | if (!handle->buffer) |
1862 | return -ENOMEM; | |
f577eb30 RW |
1863 | } |
1864 | } else { | |
8357376d | 1865 | copy_last_highmem_page(); |
940864dd | 1866 | handle->buffer = get_buffer(&orig_bm, &ca); |
8357376d RW |
1867 | if (handle->buffer != buffer) |
1868 | handle->sync_read = 0; | |
f577eb30 | 1869 | } |
fb13a28b | 1870 | handle->prev = handle->cur; |
f577eb30 | 1871 | } |
fb13a28b RW |
1872 | handle->buf_offset = handle->cur_offset; |
1873 | if (handle->cur_offset + count >= PAGE_SIZE) { | |
1874 | count = PAGE_SIZE - handle->cur_offset; | |
1875 | handle->cur_offset = 0; | |
1876 | handle->cur++; | |
f577eb30 | 1877 | } else { |
fb13a28b | 1878 | handle->cur_offset += count; |
f577eb30 RW |
1879 | } |
1880 | handle->offset += count; | |
1881 | return count; | |
1882 | } | |
1883 | ||
8357376d RW |
1884 | /** |
1885 | * snapshot_write_finalize - must be called after the last call to | |
1886 | * snapshot_write_next() in case the last page in the image happens | |
1887 | * to be a highmem page and its contents should be stored in the | |
1888 | * highmem. Additionally, it releases the memory that will not be | |
1889 | * used any more. | |
1890 | */ | |
1891 | ||
1892 | void snapshot_write_finalize(struct snapshot_handle *handle) | |
1893 | { | |
1894 | copy_last_highmem_page(); | |
1895 | /* Free only if we have loaded the image entirely */ | |
1896 | if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages) { | |
1897 | memory_bm_free(&orig_bm, PG_UNSAFE_CLEAR); | |
1898 | free_highmem_data(); | |
1899 | } | |
1900 | } | |
1901 | ||
f577eb30 RW |
1902 | int snapshot_image_loaded(struct snapshot_handle *handle) |
1903 | { | |
8357376d | 1904 | return !(!nr_copy_pages || !last_highmem_page_copied() || |
940864dd RW |
1905 | handle->cur <= nr_meta_pages + nr_copy_pages); |
1906 | } | |
1907 | ||
8357376d RW |
1908 | #ifdef CONFIG_HIGHMEM |
1909 | /* Assumes that @buf is ready and points to a "safe" page */ | |
1910 | static inline void | |
1911 | swap_two_pages_data(struct page *p1, struct page *p2, void *buf) | |
940864dd | 1912 | { |
8357376d RW |
1913 | void *kaddr1, *kaddr2; |
1914 | ||
1915 | kaddr1 = kmap_atomic(p1, KM_USER0); | |
1916 | kaddr2 = kmap_atomic(p2, KM_USER1); | |
1917 | memcpy(buf, kaddr1, PAGE_SIZE); | |
1918 | memcpy(kaddr1, kaddr2, PAGE_SIZE); | |
1919 | memcpy(kaddr2, buf, PAGE_SIZE); | |
1920 | kunmap_atomic(kaddr1, KM_USER0); | |
1921 | kunmap_atomic(kaddr2, KM_USER1); | |
1922 | } | |
1923 | ||
1924 | /** | |
1925 | * restore_highmem - for each highmem page that was allocated before | |
1926 | * the suspend and included in the suspend image, and also has been | |
1927 | * allocated by the "resume" kernel swap its current (ie. "before | |
1928 | * resume") contents with the previous (ie. "before suspend") one. | |
1929 | * | |
1930 | * If the resume eventually fails, we can call this function once | |
1931 | * again and restore the "before resume" highmem state. | |
1932 | */ | |
1933 | ||
1934 | int restore_highmem(void) | |
1935 | { | |
1936 | struct highmem_pbe *pbe = highmem_pblist; | |
1937 | void *buf; | |
1938 | ||
1939 | if (!pbe) | |
1940 | return 0; | |
1941 | ||
1942 | buf = get_image_page(GFP_ATOMIC, PG_SAFE); | |
1943 | if (!buf) | |
1944 | return -ENOMEM; | |
1945 | ||
1946 | while (pbe) { | |
1947 | swap_two_pages_data(pbe->copy_page, pbe->orig_page, buf); | |
1948 | pbe = pbe->next; | |
1949 | } | |
1950 | free_image_page(buf, PG_UNSAFE_CLEAR); | |
1951 | return 0; | |
f577eb30 | 1952 | } |
8357376d | 1953 | #endif /* CONFIG_HIGHMEM */ |