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++) | |
c5a69adf RW |
712 | if (pfn_valid(pfn)) |
713 | memory_bm_set_bit(bm, pfn); | |
74dfd666 RW |
714 | } |
715 | } | |
716 | ||
717 | /** | |
718 | * create_basic_memory_bitmaps - create bitmaps needed for marking page | |
719 | * frames that should not be saved and free page frames. The pointers | |
720 | * forbidden_pages_map and free_pages_map are only modified if everything | |
721 | * goes well, because we don't want the bits to be used before both bitmaps | |
722 | * are set up. | |
723 | */ | |
724 | ||
725 | int create_basic_memory_bitmaps(void) | |
726 | { | |
727 | struct memory_bitmap *bm1, *bm2; | |
728 | int error = 0; | |
729 | ||
730 | BUG_ON(forbidden_pages_map || free_pages_map); | |
731 | ||
0709db60 | 732 | bm1 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL); |
74dfd666 RW |
733 | if (!bm1) |
734 | return -ENOMEM; | |
735 | ||
0709db60 | 736 | error = memory_bm_create(bm1, GFP_KERNEL, PG_ANY); |
74dfd666 RW |
737 | if (error) |
738 | goto Free_first_object; | |
739 | ||
0709db60 | 740 | bm2 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL); |
74dfd666 RW |
741 | if (!bm2) |
742 | goto Free_first_bitmap; | |
743 | ||
0709db60 | 744 | error = memory_bm_create(bm2, GFP_KERNEL, PG_ANY); |
74dfd666 RW |
745 | if (error) |
746 | goto Free_second_object; | |
747 | ||
748 | forbidden_pages_map = bm1; | |
749 | free_pages_map = bm2; | |
750 | mark_nosave_pages(forbidden_pages_map); | |
751 | ||
752 | printk("swsusp: Basic memory bitmaps created\n"); | |
753 | ||
754 | return 0; | |
755 | ||
756 | Free_second_object: | |
757 | kfree(bm2); | |
758 | Free_first_bitmap: | |
759 | memory_bm_free(bm1, PG_UNSAFE_CLEAR); | |
760 | Free_first_object: | |
761 | kfree(bm1); | |
762 | return -ENOMEM; | |
763 | } | |
764 | ||
765 | /** | |
766 | * free_basic_memory_bitmaps - free memory bitmaps allocated by | |
767 | * create_basic_memory_bitmaps(). The auxiliary pointers are necessary | |
768 | * so that the bitmaps themselves are not referred to while they are being | |
769 | * freed. | |
770 | */ | |
771 | ||
772 | void free_basic_memory_bitmaps(void) | |
773 | { | |
774 | struct memory_bitmap *bm1, *bm2; | |
775 | ||
776 | BUG_ON(!(forbidden_pages_map && free_pages_map)); | |
777 | ||
778 | bm1 = forbidden_pages_map; | |
779 | bm2 = free_pages_map; | |
780 | forbidden_pages_map = NULL; | |
781 | free_pages_map = NULL; | |
782 | memory_bm_free(bm1, PG_UNSAFE_CLEAR); | |
783 | kfree(bm1); | |
784 | memory_bm_free(bm2, PG_UNSAFE_CLEAR); | |
785 | kfree(bm2); | |
786 | ||
787 | printk("swsusp: Basic memory bitmaps freed\n"); | |
788 | } | |
789 | ||
b788db79 RW |
790 | /** |
791 | * snapshot_additional_pages - estimate the number of additional pages | |
792 | * be needed for setting up the suspend image data structures for given | |
793 | * zone (usually the returned value is greater than the exact number) | |
794 | */ | |
795 | ||
796 | unsigned int snapshot_additional_pages(struct zone *zone) | |
797 | { | |
798 | unsigned int res; | |
799 | ||
800 | res = DIV_ROUND_UP(zone->spanned_pages, BM_BITS_PER_BLOCK); | |
801 | res += DIV_ROUND_UP(res * sizeof(struct bm_block), PAGE_SIZE); | |
8357376d | 802 | return 2 * res; |
b788db79 RW |
803 | } |
804 | ||
8357376d RW |
805 | #ifdef CONFIG_HIGHMEM |
806 | /** | |
807 | * count_free_highmem_pages - compute the total number of free highmem | |
808 | * pages, system-wide. | |
809 | */ | |
810 | ||
811 | static unsigned int count_free_highmem_pages(void) | |
812 | { | |
813 | struct zone *zone; | |
814 | unsigned int cnt = 0; | |
815 | ||
816 | for_each_zone(zone) | |
817 | if (populated_zone(zone) && is_highmem(zone)) | |
d23ad423 | 818 | cnt += zone_page_state(zone, NR_FREE_PAGES); |
8357376d RW |
819 | |
820 | return cnt; | |
821 | } | |
822 | ||
823 | /** | |
824 | * saveable_highmem_page - Determine whether a highmem page should be | |
825 | * included in the suspend image. | |
826 | * | |
827 | * We should save the page if it isn't Nosave or NosaveFree, or Reserved, | |
828 | * and it isn't a part of a free chunk of pages. | |
829 | */ | |
830 | ||
831 | static struct page *saveable_highmem_page(unsigned long pfn) | |
832 | { | |
833 | struct page *page; | |
834 | ||
835 | if (!pfn_valid(pfn)) | |
836 | return NULL; | |
837 | ||
838 | page = pfn_to_page(pfn); | |
839 | ||
840 | BUG_ON(!PageHighMem(page)); | |
841 | ||
7be98234 RW |
842 | if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page) || |
843 | PageReserved(page)) | |
8357376d RW |
844 | return NULL; |
845 | ||
846 | return page; | |
847 | } | |
848 | ||
849 | /** | |
850 | * count_highmem_pages - compute the total number of saveable highmem | |
851 | * pages. | |
852 | */ | |
853 | ||
854 | unsigned int count_highmem_pages(void) | |
855 | { | |
856 | struct zone *zone; | |
857 | unsigned int n = 0; | |
858 | ||
859 | for_each_zone(zone) { | |
860 | unsigned long pfn, max_zone_pfn; | |
861 | ||
862 | if (!is_highmem(zone)) | |
863 | continue; | |
864 | ||
865 | mark_free_pages(zone); | |
866 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; | |
867 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
868 | if (saveable_highmem_page(pfn)) | |
869 | n++; | |
870 | } | |
871 | return n; | |
872 | } | |
873 | #else | |
874 | static inline void *saveable_highmem_page(unsigned long pfn) { return NULL; } | |
875 | static inline unsigned int count_highmem_pages(void) { return 0; } | |
876 | #endif /* CONFIG_HIGHMEM */ | |
877 | ||
25761b6e | 878 | /** |
8357376d RW |
879 | * saveable - Determine whether a non-highmem page should be included in |
880 | * the suspend image. | |
25761b6e | 881 | * |
8357376d RW |
882 | * We should save the page if it isn't Nosave, and is not in the range |
883 | * of pages statically defined as 'unsaveable', and it isn't a part of | |
884 | * a free chunk of pages. | |
25761b6e RW |
885 | */ |
886 | ||
ae83c5ee | 887 | static struct page *saveable_page(unsigned long pfn) |
25761b6e | 888 | { |
de491861 | 889 | struct page *page; |
25761b6e RW |
890 | |
891 | if (!pfn_valid(pfn)) | |
ae83c5ee | 892 | return NULL; |
25761b6e RW |
893 | |
894 | page = pfn_to_page(pfn); | |
ae83c5ee | 895 | |
8357376d RW |
896 | BUG_ON(PageHighMem(page)); |
897 | ||
7be98234 | 898 | if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page)) |
ae83c5ee | 899 | return NULL; |
8357376d | 900 | |
72a97e08 | 901 | if (PageReserved(page) && pfn_is_nosave(pfn)) |
ae83c5ee | 902 | return NULL; |
25761b6e | 903 | |
ae83c5ee | 904 | return page; |
25761b6e RW |
905 | } |
906 | ||
8357376d RW |
907 | /** |
908 | * count_data_pages - compute the total number of saveable non-highmem | |
909 | * pages. | |
910 | */ | |
911 | ||
72a97e08 | 912 | unsigned int count_data_pages(void) |
25761b6e RW |
913 | { |
914 | struct zone *zone; | |
ae83c5ee | 915 | unsigned long pfn, max_zone_pfn; |
dc19d507 | 916 | unsigned int n = 0; |
25761b6e | 917 | |
8357376d | 918 | for_each_zone(zone) { |
25761b6e RW |
919 | if (is_highmem(zone)) |
920 | continue; | |
8357376d | 921 | |
25761b6e | 922 | mark_free_pages(zone); |
ae83c5ee RW |
923 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
924 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
8357376d RW |
925 | if(saveable_page(pfn)) |
926 | n++; | |
25761b6e | 927 | } |
a0f49651 | 928 | return n; |
25761b6e RW |
929 | } |
930 | ||
8357376d RW |
931 | /* This is needed, because copy_page and memcpy are not usable for copying |
932 | * task structs. | |
933 | */ | |
934 | static inline void do_copy_page(long *dst, long *src) | |
f623f0db RW |
935 | { |
936 | int n; | |
937 | ||
f623f0db RW |
938 | for (n = PAGE_SIZE / sizeof(long); n; n--) |
939 | *dst++ = *src++; | |
940 | } | |
941 | ||
8357376d RW |
942 | #ifdef CONFIG_HIGHMEM |
943 | static inline struct page * | |
944 | page_is_saveable(struct zone *zone, unsigned long pfn) | |
945 | { | |
946 | return is_highmem(zone) ? | |
947 | saveable_highmem_page(pfn) : saveable_page(pfn); | |
948 | } | |
949 | ||
950 | static inline void | |
951 | copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) | |
952 | { | |
953 | struct page *s_page, *d_page; | |
954 | void *src, *dst; | |
955 | ||
956 | s_page = pfn_to_page(src_pfn); | |
957 | d_page = pfn_to_page(dst_pfn); | |
958 | if (PageHighMem(s_page)) { | |
959 | src = kmap_atomic(s_page, KM_USER0); | |
960 | dst = kmap_atomic(d_page, KM_USER1); | |
961 | do_copy_page(dst, src); | |
962 | kunmap_atomic(src, KM_USER0); | |
963 | kunmap_atomic(dst, KM_USER1); | |
964 | } else { | |
965 | src = page_address(s_page); | |
966 | if (PageHighMem(d_page)) { | |
967 | /* Page pointed to by src may contain some kernel | |
968 | * data modified by kmap_atomic() | |
969 | */ | |
970 | do_copy_page(buffer, src); | |
971 | dst = kmap_atomic(pfn_to_page(dst_pfn), KM_USER0); | |
972 | memcpy(dst, buffer, PAGE_SIZE); | |
973 | kunmap_atomic(dst, KM_USER0); | |
974 | } else { | |
975 | dst = page_address(d_page); | |
976 | do_copy_page(dst, src); | |
977 | } | |
978 | } | |
979 | } | |
980 | #else | |
981 | #define page_is_saveable(zone, pfn) saveable_page(pfn) | |
982 | ||
983 | static inline void | |
984 | copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) | |
985 | { | |
986 | do_copy_page(page_address(pfn_to_page(dst_pfn)), | |
987 | page_address(pfn_to_page(src_pfn))); | |
988 | } | |
989 | #endif /* CONFIG_HIGHMEM */ | |
990 | ||
b788db79 RW |
991 | static void |
992 | copy_data_pages(struct memory_bitmap *copy_bm, struct memory_bitmap *orig_bm) | |
25761b6e RW |
993 | { |
994 | struct zone *zone; | |
b788db79 | 995 | unsigned long pfn; |
25761b6e | 996 | |
8357376d | 997 | for_each_zone(zone) { |
b788db79 RW |
998 | unsigned long max_zone_pfn; |
999 | ||
25761b6e | 1000 | mark_free_pages(zone); |
ae83c5ee | 1001 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
b788db79 | 1002 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) |
8357376d | 1003 | if (page_is_saveable(zone, pfn)) |
b788db79 | 1004 | memory_bm_set_bit(orig_bm, pfn); |
25761b6e | 1005 | } |
b788db79 RW |
1006 | memory_bm_position_reset(orig_bm); |
1007 | memory_bm_position_reset(copy_bm); | |
df7c4872 | 1008 | for(;;) { |
b788db79 | 1009 | pfn = memory_bm_next_pfn(orig_bm); |
df7c4872 FW |
1010 | if (unlikely(pfn == BM_END_OF_MAP)) |
1011 | break; | |
1012 | copy_data_page(memory_bm_next_pfn(copy_bm), pfn); | |
1013 | } | |
25761b6e RW |
1014 | } |
1015 | ||
8357376d RW |
1016 | /* Total number of image pages */ |
1017 | static unsigned int nr_copy_pages; | |
1018 | /* Number of pages needed for saving the original pfns of the image pages */ | |
1019 | static unsigned int nr_meta_pages; | |
1020 | ||
25761b6e | 1021 | /** |
940864dd | 1022 | * swsusp_free - free pages allocated for the suspend. |
cd560bb2 | 1023 | * |
940864dd RW |
1024 | * Suspend pages are alocated before the atomic copy is made, so we |
1025 | * need to release them after the resume. | |
25761b6e RW |
1026 | */ |
1027 | ||
1028 | void swsusp_free(void) | |
1029 | { | |
1030 | struct zone *zone; | |
ae83c5ee | 1031 | unsigned long pfn, max_zone_pfn; |
25761b6e RW |
1032 | |
1033 | for_each_zone(zone) { | |
ae83c5ee RW |
1034 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
1035 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
1036 | if (pfn_valid(pfn)) { | |
1037 | struct page *page = pfn_to_page(pfn); | |
1038 | ||
7be98234 RW |
1039 | if (swsusp_page_is_forbidden(page) && |
1040 | swsusp_page_is_free(page)) { | |
1041 | swsusp_unset_page_forbidden(page); | |
1042 | swsusp_unset_page_free(page); | |
8357376d | 1043 | __free_page(page); |
25761b6e RW |
1044 | } |
1045 | } | |
1046 | } | |
f577eb30 RW |
1047 | nr_copy_pages = 0; |
1048 | nr_meta_pages = 0; | |
75534b50 | 1049 | restore_pblist = NULL; |
6e1819d6 | 1050 | buffer = NULL; |
25761b6e RW |
1051 | } |
1052 | ||
8357376d RW |
1053 | #ifdef CONFIG_HIGHMEM |
1054 | /** | |
1055 | * count_pages_for_highmem - compute the number of non-highmem pages | |
1056 | * that will be necessary for creating copies of highmem pages. | |
1057 | */ | |
1058 | ||
1059 | static unsigned int count_pages_for_highmem(unsigned int nr_highmem) | |
1060 | { | |
1061 | unsigned int free_highmem = count_free_highmem_pages(); | |
1062 | ||
1063 | if (free_highmem >= nr_highmem) | |
1064 | nr_highmem = 0; | |
1065 | else | |
1066 | nr_highmem -= free_highmem; | |
1067 | ||
1068 | return nr_highmem; | |
1069 | } | |
1070 | #else | |
1071 | static unsigned int | |
1072 | count_pages_for_highmem(unsigned int nr_highmem) { return 0; } | |
1073 | #endif /* CONFIG_HIGHMEM */ | |
25761b6e RW |
1074 | |
1075 | /** | |
8357376d RW |
1076 | * enough_free_mem - Make sure we have enough free memory for the |
1077 | * snapshot image. | |
25761b6e RW |
1078 | */ |
1079 | ||
8357376d | 1080 | static int enough_free_mem(unsigned int nr_pages, unsigned int nr_highmem) |
25761b6e | 1081 | { |
e5e2fa78 | 1082 | struct zone *zone; |
940864dd | 1083 | unsigned int free = 0, meta = 0; |
e5e2fa78 | 1084 | |
8357376d RW |
1085 | for_each_zone(zone) { |
1086 | meta += snapshot_additional_pages(zone); | |
1087 | if (!is_highmem(zone)) | |
d23ad423 | 1088 | free += zone_page_state(zone, NR_FREE_PAGES); |
8357376d | 1089 | } |
940864dd | 1090 | |
8357376d RW |
1091 | nr_pages += count_pages_for_highmem(nr_highmem); |
1092 | pr_debug("swsusp: Normal pages needed: %u + %u + %u, available pages: %u\n", | |
940864dd RW |
1093 | nr_pages, PAGES_FOR_IO, meta, free); |
1094 | ||
1095 | return free > nr_pages + PAGES_FOR_IO + meta; | |
25761b6e RW |
1096 | } |
1097 | ||
8357376d RW |
1098 | #ifdef CONFIG_HIGHMEM |
1099 | /** | |
1100 | * get_highmem_buffer - if there are some highmem pages in the suspend | |
1101 | * image, we may need the buffer to copy them and/or load their data. | |
1102 | */ | |
1103 | ||
1104 | static inline int get_highmem_buffer(int safe_needed) | |
1105 | { | |
1106 | buffer = get_image_page(GFP_ATOMIC | __GFP_COLD, safe_needed); | |
1107 | return buffer ? 0 : -ENOMEM; | |
1108 | } | |
1109 | ||
1110 | /** | |
1111 | * alloc_highmem_image_pages - allocate some highmem pages for the image. | |
1112 | * Try to allocate as many pages as needed, but if the number of free | |
1113 | * highmem pages is lesser than that, allocate them all. | |
1114 | */ | |
1115 | ||
1116 | static inline unsigned int | |
1117 | alloc_highmem_image_pages(struct memory_bitmap *bm, unsigned int nr_highmem) | |
1118 | { | |
1119 | unsigned int to_alloc = count_free_highmem_pages(); | |
1120 | ||
1121 | if (to_alloc > nr_highmem) | |
1122 | to_alloc = nr_highmem; | |
1123 | ||
1124 | nr_highmem -= to_alloc; | |
1125 | while (to_alloc-- > 0) { | |
1126 | struct page *page; | |
1127 | ||
1128 | page = alloc_image_page(__GFP_HIGHMEM); | |
1129 | memory_bm_set_bit(bm, page_to_pfn(page)); | |
1130 | } | |
1131 | return nr_highmem; | |
1132 | } | |
1133 | #else | |
1134 | static inline int get_highmem_buffer(int safe_needed) { return 0; } | |
1135 | ||
1136 | static inline unsigned int | |
1137 | alloc_highmem_image_pages(struct memory_bitmap *bm, unsigned int n) { return 0; } | |
1138 | #endif /* CONFIG_HIGHMEM */ | |
1139 | ||
1140 | /** | |
1141 | * swsusp_alloc - allocate memory for the suspend image | |
1142 | * | |
1143 | * We first try to allocate as many highmem pages as there are | |
1144 | * saveable highmem pages in the system. If that fails, we allocate | |
1145 | * non-highmem pages for the copies of the remaining highmem ones. | |
1146 | * | |
1147 | * In this approach it is likely that the copies of highmem pages will | |
1148 | * also be located in the high memory, because of the way in which | |
1149 | * copy_data_pages() works. | |
1150 | */ | |
1151 | ||
b788db79 RW |
1152 | static int |
1153 | swsusp_alloc(struct memory_bitmap *orig_bm, struct memory_bitmap *copy_bm, | |
8357376d | 1154 | unsigned int nr_pages, unsigned int nr_highmem) |
054bd4c1 | 1155 | { |
b788db79 | 1156 | int error; |
054bd4c1 | 1157 | |
b788db79 RW |
1158 | error = memory_bm_create(orig_bm, GFP_ATOMIC | __GFP_COLD, PG_ANY); |
1159 | if (error) | |
1160 | goto Free; | |
25761b6e | 1161 | |
b788db79 RW |
1162 | error = memory_bm_create(copy_bm, GFP_ATOMIC | __GFP_COLD, PG_ANY); |
1163 | if (error) | |
1164 | goto Free; | |
25761b6e | 1165 | |
8357376d RW |
1166 | if (nr_highmem > 0) { |
1167 | error = get_highmem_buffer(PG_ANY); | |
1168 | if (error) | |
1169 | goto Free; | |
1170 | ||
1171 | nr_pages += alloc_highmem_image_pages(copy_bm, nr_highmem); | |
1172 | } | |
b788db79 | 1173 | while (nr_pages-- > 0) { |
8357376d RW |
1174 | struct page *page = alloc_image_page(GFP_ATOMIC | __GFP_COLD); |
1175 | ||
b788db79 RW |
1176 | if (!page) |
1177 | goto Free; | |
25761b6e | 1178 | |
b788db79 | 1179 | memory_bm_set_bit(copy_bm, page_to_pfn(page)); |
25761b6e | 1180 | } |
b788db79 | 1181 | return 0; |
25761b6e | 1182 | |
59a49335 | 1183 | Free: |
b788db79 RW |
1184 | swsusp_free(); |
1185 | return -ENOMEM; | |
25761b6e RW |
1186 | } |
1187 | ||
8357376d RW |
1188 | /* Memory bitmap used for marking saveable pages (during suspend) or the |
1189 | * suspend image pages (during resume) | |
1190 | */ | |
b788db79 | 1191 | static struct memory_bitmap orig_bm; |
8357376d RW |
1192 | /* Memory bitmap used on suspend for marking allocated pages that will contain |
1193 | * the copies of saveable pages. During resume it is initially used for | |
1194 | * marking the suspend image pages, but then its set bits are duplicated in | |
1195 | * @orig_bm and it is released. Next, on systems with high memory, it may be | |
1196 | * used for marking "safe" highmem pages, but it has to be reinitialized for | |
1197 | * this purpose. | |
b788db79 RW |
1198 | */ |
1199 | static struct memory_bitmap copy_bm; | |
1200 | ||
2e32a43e | 1201 | asmlinkage int swsusp_save(void) |
25761b6e | 1202 | { |
8357376d | 1203 | unsigned int nr_pages, nr_highmem; |
25761b6e | 1204 | |
8357376d | 1205 | printk("swsusp: critical section: \n"); |
25761b6e RW |
1206 | |
1207 | drain_local_pages(); | |
a0f49651 | 1208 | nr_pages = count_data_pages(); |
8357376d RW |
1209 | nr_highmem = count_highmem_pages(); |
1210 | printk("swsusp: Need to copy %u pages\n", nr_pages + nr_highmem); | |
25761b6e | 1211 | |
8357376d | 1212 | if (!enough_free_mem(nr_pages, nr_highmem)) { |
25761b6e RW |
1213 | printk(KERN_ERR "swsusp: Not enough free memory\n"); |
1214 | return -ENOMEM; | |
1215 | } | |
1216 | ||
8357376d RW |
1217 | if (swsusp_alloc(&orig_bm, ©_bm, nr_pages, nr_highmem)) { |
1218 | printk(KERN_ERR "swsusp: Memory allocation failed\n"); | |
a0f49651 | 1219 | return -ENOMEM; |
8357376d | 1220 | } |
25761b6e RW |
1221 | |
1222 | /* During allocating of suspend pagedir, new cold pages may appear. | |
1223 | * Kill them. | |
1224 | */ | |
1225 | drain_local_pages(); | |
b788db79 | 1226 | copy_data_pages(©_bm, &orig_bm); |
25761b6e RW |
1227 | |
1228 | /* | |
1229 | * End of critical section. From now on, we can write to memory, | |
1230 | * but we should not touch disk. This specially means we must _not_ | |
1231 | * touch swap space! Except we must write out our image of course. | |
1232 | */ | |
1233 | ||
8357376d | 1234 | nr_pages += nr_highmem; |
a0f49651 | 1235 | nr_copy_pages = nr_pages; |
8357376d | 1236 | nr_meta_pages = DIV_ROUND_UP(nr_pages * sizeof(long), PAGE_SIZE); |
a0f49651 | 1237 | |
d60846c4 | 1238 | printk("swsusp: critical section: done (%d pages copied)\n", nr_pages); |
8357376d | 1239 | |
25761b6e RW |
1240 | return 0; |
1241 | } | |
f577eb30 | 1242 | |
d307c4a8 RW |
1243 | #ifndef CONFIG_ARCH_HIBERNATION_HEADER |
1244 | static int init_header_complete(struct swsusp_info *info) | |
f577eb30 | 1245 | { |
d307c4a8 | 1246 | memcpy(&info->uts, init_utsname(), sizeof(struct new_utsname)); |
f577eb30 | 1247 | info->version_code = LINUX_VERSION_CODE; |
d307c4a8 RW |
1248 | return 0; |
1249 | } | |
1250 | ||
1251 | static char *check_image_kernel(struct swsusp_info *info) | |
1252 | { | |
1253 | if (info->version_code != LINUX_VERSION_CODE) | |
1254 | return "kernel version"; | |
1255 | if (strcmp(info->uts.sysname,init_utsname()->sysname)) | |
1256 | return "system type"; | |
1257 | if (strcmp(info->uts.release,init_utsname()->release)) | |
1258 | return "kernel release"; | |
1259 | if (strcmp(info->uts.version,init_utsname()->version)) | |
1260 | return "version"; | |
1261 | if (strcmp(info->uts.machine,init_utsname()->machine)) | |
1262 | return "machine"; | |
1263 | return NULL; | |
1264 | } | |
1265 | #endif /* CONFIG_ARCH_HIBERNATION_HEADER */ | |
1266 | ||
1267 | static int init_header(struct swsusp_info *info) | |
1268 | { | |
1269 | memset(info, 0, sizeof(struct swsusp_info)); | |
f577eb30 | 1270 | info->num_physpages = num_physpages; |
f577eb30 RW |
1271 | info->image_pages = nr_copy_pages; |
1272 | info->pages = nr_copy_pages + nr_meta_pages + 1; | |
6e1819d6 RW |
1273 | info->size = info->pages; |
1274 | info->size <<= PAGE_SHIFT; | |
d307c4a8 | 1275 | return init_header_complete(info); |
f577eb30 RW |
1276 | } |
1277 | ||
1278 | /** | |
940864dd RW |
1279 | * pack_pfns - pfns corresponding to the set bits found in the bitmap @bm |
1280 | * are stored in the array @buf[] (1 page at a time) | |
f577eb30 RW |
1281 | */ |
1282 | ||
b788db79 | 1283 | static inline void |
940864dd | 1284 | pack_pfns(unsigned long *buf, struct memory_bitmap *bm) |
f577eb30 RW |
1285 | { |
1286 | int j; | |
1287 | ||
b788db79 | 1288 | for (j = 0; j < PAGE_SIZE / sizeof(long); j++) { |
940864dd RW |
1289 | buf[j] = memory_bm_next_pfn(bm); |
1290 | if (unlikely(buf[j] == BM_END_OF_MAP)) | |
b788db79 | 1291 | break; |
f577eb30 | 1292 | } |
f577eb30 RW |
1293 | } |
1294 | ||
1295 | /** | |
1296 | * snapshot_read_next - used for reading the system memory snapshot. | |
1297 | * | |
1298 | * On the first call to it @handle should point to a zeroed | |
1299 | * snapshot_handle structure. The structure gets updated and a pointer | |
1300 | * to it should be passed to this function every next time. | |
1301 | * | |
1302 | * The @count parameter should contain the number of bytes the caller | |
1303 | * wants to read from the snapshot. It must not be zero. | |
1304 | * | |
1305 | * On success the function returns a positive number. Then, the caller | |
1306 | * is allowed to read up to the returned number of bytes from the memory | |
1307 | * location computed by the data_of() macro. The number returned | |
1308 | * may be smaller than @count, but this only happens if the read would | |
1309 | * cross a page boundary otherwise. | |
1310 | * | |
1311 | * The function returns 0 to indicate the end of data stream condition, | |
1312 | * and a negative number is returned on error. In such cases the | |
1313 | * structure pointed to by @handle is not updated and should not be used | |
1314 | * any more. | |
1315 | */ | |
1316 | ||
1317 | int snapshot_read_next(struct snapshot_handle *handle, size_t count) | |
1318 | { | |
fb13a28b | 1319 | if (handle->cur > nr_meta_pages + nr_copy_pages) |
f577eb30 | 1320 | return 0; |
b788db79 | 1321 | |
f577eb30 RW |
1322 | if (!buffer) { |
1323 | /* This makes the buffer be freed by swsusp_free() */ | |
8357376d | 1324 | buffer = get_image_page(GFP_ATOMIC, PG_ANY); |
f577eb30 RW |
1325 | if (!buffer) |
1326 | return -ENOMEM; | |
1327 | } | |
1328 | if (!handle->offset) { | |
d307c4a8 RW |
1329 | int error; |
1330 | ||
1331 | error = init_header((struct swsusp_info *)buffer); | |
1332 | if (error) | |
1333 | return error; | |
f577eb30 | 1334 | handle->buffer = buffer; |
b788db79 RW |
1335 | memory_bm_position_reset(&orig_bm); |
1336 | memory_bm_position_reset(©_bm); | |
f577eb30 | 1337 | } |
fb13a28b RW |
1338 | if (handle->prev < handle->cur) { |
1339 | if (handle->cur <= nr_meta_pages) { | |
b788db79 | 1340 | memset(buffer, 0, PAGE_SIZE); |
940864dd | 1341 | pack_pfns(buffer, &orig_bm); |
f577eb30 | 1342 | } else { |
8357376d | 1343 | struct page *page; |
b788db79 | 1344 | |
8357376d RW |
1345 | page = pfn_to_page(memory_bm_next_pfn(©_bm)); |
1346 | if (PageHighMem(page)) { | |
1347 | /* Highmem pages are copied to the buffer, | |
1348 | * because we can't return with a kmapped | |
1349 | * highmem page (we may not be called again). | |
1350 | */ | |
1351 | void *kaddr; | |
1352 | ||
1353 | kaddr = kmap_atomic(page, KM_USER0); | |
1354 | memcpy(buffer, kaddr, PAGE_SIZE); | |
1355 | kunmap_atomic(kaddr, KM_USER0); | |
1356 | handle->buffer = buffer; | |
1357 | } else { | |
1358 | handle->buffer = page_address(page); | |
1359 | } | |
f577eb30 | 1360 | } |
fb13a28b | 1361 | handle->prev = handle->cur; |
f577eb30 | 1362 | } |
fb13a28b RW |
1363 | handle->buf_offset = handle->cur_offset; |
1364 | if (handle->cur_offset + count >= PAGE_SIZE) { | |
1365 | count = PAGE_SIZE - handle->cur_offset; | |
1366 | handle->cur_offset = 0; | |
1367 | handle->cur++; | |
f577eb30 | 1368 | } else { |
fb13a28b | 1369 | handle->cur_offset += count; |
f577eb30 RW |
1370 | } |
1371 | handle->offset += count; | |
1372 | return count; | |
1373 | } | |
1374 | ||
1375 | /** | |
1376 | * mark_unsafe_pages - mark the pages that cannot be used for storing | |
1377 | * the image during resume, because they conflict with the pages that | |
1378 | * had been used before suspend | |
1379 | */ | |
1380 | ||
940864dd | 1381 | static int mark_unsafe_pages(struct memory_bitmap *bm) |
f577eb30 RW |
1382 | { |
1383 | struct zone *zone; | |
ae83c5ee | 1384 | unsigned long pfn, max_zone_pfn; |
f577eb30 RW |
1385 | |
1386 | /* Clear page flags */ | |
8357376d | 1387 | for_each_zone(zone) { |
ae83c5ee RW |
1388 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
1389 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
1390 | if (pfn_valid(pfn)) | |
7be98234 | 1391 | swsusp_unset_page_free(pfn_to_page(pfn)); |
f577eb30 RW |
1392 | } |
1393 | ||
940864dd RW |
1394 | /* Mark pages that correspond to the "original" pfns as "unsafe" */ |
1395 | memory_bm_position_reset(bm); | |
1396 | do { | |
1397 | pfn = memory_bm_next_pfn(bm); | |
1398 | if (likely(pfn != BM_END_OF_MAP)) { | |
1399 | if (likely(pfn_valid(pfn))) | |
7be98234 | 1400 | swsusp_set_page_free(pfn_to_page(pfn)); |
940864dd RW |
1401 | else |
1402 | return -EFAULT; | |
1403 | } | |
1404 | } while (pfn != BM_END_OF_MAP); | |
f577eb30 | 1405 | |
940864dd | 1406 | allocated_unsafe_pages = 0; |
968808b8 | 1407 | |
f577eb30 RW |
1408 | return 0; |
1409 | } | |
1410 | ||
940864dd RW |
1411 | static void |
1412 | duplicate_memory_bitmap(struct memory_bitmap *dst, struct memory_bitmap *src) | |
f577eb30 | 1413 | { |
940864dd RW |
1414 | unsigned long pfn; |
1415 | ||
1416 | memory_bm_position_reset(src); | |
1417 | pfn = memory_bm_next_pfn(src); | |
1418 | while (pfn != BM_END_OF_MAP) { | |
1419 | memory_bm_set_bit(dst, pfn); | |
1420 | pfn = memory_bm_next_pfn(src); | |
f577eb30 RW |
1421 | } |
1422 | } | |
1423 | ||
d307c4a8 | 1424 | static int check_header(struct swsusp_info *info) |
f577eb30 | 1425 | { |
d307c4a8 | 1426 | char *reason; |
f577eb30 | 1427 | |
d307c4a8 RW |
1428 | reason = check_image_kernel(info); |
1429 | if (!reason && info->num_physpages != num_physpages) | |
f577eb30 | 1430 | reason = "memory size"; |
f577eb30 RW |
1431 | if (reason) { |
1432 | printk(KERN_ERR "swsusp: Resume mismatch: %s\n", reason); | |
1433 | return -EPERM; | |
1434 | } | |
1435 | return 0; | |
1436 | } | |
1437 | ||
1438 | /** | |
1439 | * load header - check the image header and copy data from it | |
1440 | */ | |
1441 | ||
940864dd RW |
1442 | static int |
1443 | load_header(struct swsusp_info *info) | |
f577eb30 RW |
1444 | { |
1445 | int error; | |
f577eb30 | 1446 | |
940864dd | 1447 | restore_pblist = NULL; |
f577eb30 RW |
1448 | error = check_header(info); |
1449 | if (!error) { | |
f577eb30 RW |
1450 | nr_copy_pages = info->image_pages; |
1451 | nr_meta_pages = info->pages - info->image_pages - 1; | |
1452 | } | |
1453 | return error; | |
1454 | } | |
1455 | ||
1456 | /** | |
940864dd RW |
1457 | * unpack_orig_pfns - for each element of @buf[] (1 page at a time) set |
1458 | * the corresponding bit in the memory bitmap @bm | |
f577eb30 RW |
1459 | */ |
1460 | ||
940864dd RW |
1461 | static inline void |
1462 | unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm) | |
f577eb30 RW |
1463 | { |
1464 | int j; | |
1465 | ||
940864dd RW |
1466 | for (j = 0; j < PAGE_SIZE / sizeof(long); j++) { |
1467 | if (unlikely(buf[j] == BM_END_OF_MAP)) | |
1468 | break; | |
1469 | ||
1470 | memory_bm_set_bit(bm, buf[j]); | |
f577eb30 | 1471 | } |
f577eb30 RW |
1472 | } |
1473 | ||
8357376d RW |
1474 | /* List of "safe" pages that may be used to store data loaded from the suspend |
1475 | * image | |
1476 | */ | |
1477 | static struct linked_page *safe_pages_list; | |
1478 | ||
1479 | #ifdef CONFIG_HIGHMEM | |
1480 | /* struct highmem_pbe is used for creating the list of highmem pages that | |
1481 | * should be restored atomically during the resume from disk, because the page | |
1482 | * frames they have occupied before the suspend are in use. | |
1483 | */ | |
1484 | struct highmem_pbe { | |
1485 | struct page *copy_page; /* data is here now */ | |
1486 | struct page *orig_page; /* data was here before the suspend */ | |
1487 | struct highmem_pbe *next; | |
1488 | }; | |
1489 | ||
1490 | /* List of highmem PBEs needed for restoring the highmem pages that were | |
1491 | * allocated before the suspend and included in the suspend image, but have | |
1492 | * also been allocated by the "resume" kernel, so their contents cannot be | |
1493 | * written directly to their "original" page frames. | |
1494 | */ | |
1495 | static struct highmem_pbe *highmem_pblist; | |
1496 | ||
1497 | /** | |
1498 | * count_highmem_image_pages - compute the number of highmem pages in the | |
1499 | * suspend image. The bits in the memory bitmap @bm that correspond to the | |
1500 | * image pages are assumed to be set. | |
1501 | */ | |
1502 | ||
1503 | static unsigned int count_highmem_image_pages(struct memory_bitmap *bm) | |
1504 | { | |
1505 | unsigned long pfn; | |
1506 | unsigned int cnt = 0; | |
1507 | ||
1508 | memory_bm_position_reset(bm); | |
1509 | pfn = memory_bm_next_pfn(bm); | |
1510 | while (pfn != BM_END_OF_MAP) { | |
1511 | if (PageHighMem(pfn_to_page(pfn))) | |
1512 | cnt++; | |
1513 | ||
1514 | pfn = memory_bm_next_pfn(bm); | |
1515 | } | |
1516 | return cnt; | |
1517 | } | |
1518 | ||
1519 | /** | |
1520 | * prepare_highmem_image - try to allocate as many highmem pages as | |
1521 | * there are highmem image pages (@nr_highmem_p points to the variable | |
1522 | * containing the number of highmem image pages). The pages that are | |
1523 | * "safe" (ie. will not be overwritten when the suspend image is | |
1524 | * restored) have the corresponding bits set in @bm (it must be | |
1525 | * unitialized). | |
1526 | * | |
1527 | * NOTE: This function should not be called if there are no highmem | |
1528 | * image pages. | |
1529 | */ | |
1530 | ||
1531 | static unsigned int safe_highmem_pages; | |
1532 | ||
1533 | static struct memory_bitmap *safe_highmem_bm; | |
1534 | ||
1535 | static int | |
1536 | prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p) | |
1537 | { | |
1538 | unsigned int to_alloc; | |
1539 | ||
1540 | if (memory_bm_create(bm, GFP_ATOMIC, PG_SAFE)) | |
1541 | return -ENOMEM; | |
1542 | ||
1543 | if (get_highmem_buffer(PG_SAFE)) | |
1544 | return -ENOMEM; | |
1545 | ||
1546 | to_alloc = count_free_highmem_pages(); | |
1547 | if (to_alloc > *nr_highmem_p) | |
1548 | to_alloc = *nr_highmem_p; | |
1549 | else | |
1550 | *nr_highmem_p = to_alloc; | |
1551 | ||
1552 | safe_highmem_pages = 0; | |
1553 | while (to_alloc-- > 0) { | |
1554 | struct page *page; | |
1555 | ||
1556 | page = alloc_page(__GFP_HIGHMEM); | |
7be98234 | 1557 | if (!swsusp_page_is_free(page)) { |
8357376d RW |
1558 | /* The page is "safe", set its bit the bitmap */ |
1559 | memory_bm_set_bit(bm, page_to_pfn(page)); | |
1560 | safe_highmem_pages++; | |
1561 | } | |
1562 | /* Mark the page as allocated */ | |
7be98234 RW |
1563 | swsusp_set_page_forbidden(page); |
1564 | swsusp_set_page_free(page); | |
8357376d RW |
1565 | } |
1566 | memory_bm_position_reset(bm); | |
1567 | safe_highmem_bm = bm; | |
1568 | return 0; | |
1569 | } | |
1570 | ||
1571 | /** | |
1572 | * get_highmem_page_buffer - for given highmem image page find the buffer | |
1573 | * that suspend_write_next() should set for its caller to write to. | |
1574 | * | |
1575 | * If the page is to be saved to its "original" page frame or a copy of | |
1576 | * the page is to be made in the highmem, @buffer is returned. Otherwise, | |
1577 | * the copy of the page is to be made in normal memory, so the address of | |
1578 | * the copy is returned. | |
1579 | * | |
1580 | * If @buffer is returned, the caller of suspend_write_next() will write | |
1581 | * the page's contents to @buffer, so they will have to be copied to the | |
1582 | * right location on the next call to suspend_write_next() and it is done | |
1583 | * with the help of copy_last_highmem_page(). For this purpose, if | |
1584 | * @buffer is returned, @last_highmem page is set to the page to which | |
1585 | * the data will have to be copied from @buffer. | |
1586 | */ | |
1587 | ||
1588 | static struct page *last_highmem_page; | |
1589 | ||
1590 | static void * | |
1591 | get_highmem_page_buffer(struct page *page, struct chain_allocator *ca) | |
1592 | { | |
1593 | struct highmem_pbe *pbe; | |
1594 | void *kaddr; | |
1595 | ||
7be98234 | 1596 | if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page)) { |
8357376d RW |
1597 | /* We have allocated the "original" page frame and we can |
1598 | * use it directly to store the loaded page. | |
1599 | */ | |
1600 | last_highmem_page = page; | |
1601 | return buffer; | |
1602 | } | |
1603 | /* The "original" page frame has not been allocated and we have to | |
1604 | * use a "safe" page frame to store the loaded page. | |
1605 | */ | |
1606 | pbe = chain_alloc(ca, sizeof(struct highmem_pbe)); | |
1607 | if (!pbe) { | |
1608 | swsusp_free(); | |
1609 | return NULL; | |
1610 | } | |
1611 | pbe->orig_page = page; | |
1612 | if (safe_highmem_pages > 0) { | |
1613 | struct page *tmp; | |
1614 | ||
1615 | /* Copy of the page will be stored in high memory */ | |
1616 | kaddr = buffer; | |
1617 | tmp = pfn_to_page(memory_bm_next_pfn(safe_highmem_bm)); | |
1618 | safe_highmem_pages--; | |
1619 | last_highmem_page = tmp; | |
1620 | pbe->copy_page = tmp; | |
1621 | } else { | |
1622 | /* Copy of the page will be stored in normal memory */ | |
1623 | kaddr = safe_pages_list; | |
1624 | safe_pages_list = safe_pages_list->next; | |
1625 | pbe->copy_page = virt_to_page(kaddr); | |
1626 | } | |
1627 | pbe->next = highmem_pblist; | |
1628 | highmem_pblist = pbe; | |
1629 | return kaddr; | |
1630 | } | |
1631 | ||
1632 | /** | |
1633 | * copy_last_highmem_page - copy the contents of a highmem image from | |
1634 | * @buffer, where the caller of snapshot_write_next() has place them, | |
1635 | * to the right location represented by @last_highmem_page . | |
1636 | */ | |
1637 | ||
1638 | static void copy_last_highmem_page(void) | |
1639 | { | |
1640 | if (last_highmem_page) { | |
1641 | void *dst; | |
1642 | ||
1643 | dst = kmap_atomic(last_highmem_page, KM_USER0); | |
1644 | memcpy(dst, buffer, PAGE_SIZE); | |
1645 | kunmap_atomic(dst, KM_USER0); | |
1646 | last_highmem_page = NULL; | |
1647 | } | |
1648 | } | |
1649 | ||
1650 | static inline int last_highmem_page_copied(void) | |
1651 | { | |
1652 | return !last_highmem_page; | |
1653 | } | |
1654 | ||
1655 | static inline void free_highmem_data(void) | |
1656 | { | |
1657 | if (safe_highmem_bm) | |
1658 | memory_bm_free(safe_highmem_bm, PG_UNSAFE_CLEAR); | |
1659 | ||
1660 | if (buffer) | |
1661 | free_image_page(buffer, PG_UNSAFE_CLEAR); | |
1662 | } | |
1663 | #else | |
1664 | static inline int get_safe_write_buffer(void) { return 0; } | |
1665 | ||
1666 | static unsigned int | |
1667 | count_highmem_image_pages(struct memory_bitmap *bm) { return 0; } | |
1668 | ||
1669 | static inline int | |
1670 | prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p) | |
1671 | { | |
1672 | return 0; | |
1673 | } | |
1674 | ||
1675 | static inline void * | |
1676 | get_highmem_page_buffer(struct page *page, struct chain_allocator *ca) | |
1677 | { | |
1678 | return NULL; | |
1679 | } | |
1680 | ||
1681 | static inline void copy_last_highmem_page(void) {} | |
1682 | static inline int last_highmem_page_copied(void) { return 1; } | |
1683 | static inline void free_highmem_data(void) {} | |
1684 | #endif /* CONFIG_HIGHMEM */ | |
1685 | ||
f577eb30 | 1686 | /** |
940864dd RW |
1687 | * prepare_image - use the memory bitmap @bm to mark the pages that will |
1688 | * be overwritten in the process of restoring the system memory state | |
1689 | * from the suspend image ("unsafe" pages) and allocate memory for the | |
1690 | * image. | |
968808b8 | 1691 | * |
940864dd RW |
1692 | * The idea is to allocate a new memory bitmap first and then allocate |
1693 | * as many pages as needed for the image data, but not to assign these | |
1694 | * pages to specific tasks initially. Instead, we just mark them as | |
8357376d RW |
1695 | * allocated and create a lists of "safe" pages that will be used |
1696 | * later. On systems with high memory a list of "safe" highmem pages is | |
1697 | * also created. | |
f577eb30 RW |
1698 | */ |
1699 | ||
940864dd RW |
1700 | #define PBES_PER_LINKED_PAGE (LINKED_PAGE_DATA_SIZE / sizeof(struct pbe)) |
1701 | ||
940864dd RW |
1702 | static int |
1703 | prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm) | |
f577eb30 | 1704 | { |
8357376d | 1705 | unsigned int nr_pages, nr_highmem; |
940864dd RW |
1706 | struct linked_page *sp_list, *lp; |
1707 | int error; | |
f577eb30 | 1708 | |
8357376d RW |
1709 | /* If there is no highmem, the buffer will not be necessary */ |
1710 | free_image_page(buffer, PG_UNSAFE_CLEAR); | |
1711 | buffer = NULL; | |
1712 | ||
1713 | nr_highmem = count_highmem_image_pages(bm); | |
940864dd RW |
1714 | error = mark_unsafe_pages(bm); |
1715 | if (error) | |
1716 | goto Free; | |
1717 | ||
1718 | error = memory_bm_create(new_bm, GFP_ATOMIC, PG_SAFE); | |
1719 | if (error) | |
1720 | goto Free; | |
1721 | ||
1722 | duplicate_memory_bitmap(new_bm, bm); | |
1723 | memory_bm_free(bm, PG_UNSAFE_KEEP); | |
8357376d RW |
1724 | if (nr_highmem > 0) { |
1725 | error = prepare_highmem_image(bm, &nr_highmem); | |
1726 | if (error) | |
1727 | goto Free; | |
1728 | } | |
940864dd RW |
1729 | /* Reserve some safe pages for potential later use. |
1730 | * | |
1731 | * NOTE: This way we make sure there will be enough safe pages for the | |
1732 | * chain_alloc() in get_buffer(). It is a bit wasteful, but | |
1733 | * nr_copy_pages cannot be greater than 50% of the memory anyway. | |
1734 | */ | |
1735 | sp_list = NULL; | |
1736 | /* nr_copy_pages cannot be lesser than allocated_unsafe_pages */ | |
8357376d | 1737 | nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages; |
940864dd RW |
1738 | nr_pages = DIV_ROUND_UP(nr_pages, PBES_PER_LINKED_PAGE); |
1739 | while (nr_pages > 0) { | |
8357376d | 1740 | lp = get_image_page(GFP_ATOMIC, PG_SAFE); |
940864dd | 1741 | if (!lp) { |
f577eb30 | 1742 | error = -ENOMEM; |
940864dd RW |
1743 | goto Free; |
1744 | } | |
1745 | lp->next = sp_list; | |
1746 | sp_list = lp; | |
1747 | nr_pages--; | |
f577eb30 | 1748 | } |
940864dd RW |
1749 | /* Preallocate memory for the image */ |
1750 | safe_pages_list = NULL; | |
8357376d | 1751 | nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages; |
940864dd RW |
1752 | while (nr_pages > 0) { |
1753 | lp = (struct linked_page *)get_zeroed_page(GFP_ATOMIC); | |
1754 | if (!lp) { | |
1755 | error = -ENOMEM; | |
1756 | goto Free; | |
1757 | } | |
7be98234 | 1758 | if (!swsusp_page_is_free(virt_to_page(lp))) { |
940864dd RW |
1759 | /* The page is "safe", add it to the list */ |
1760 | lp->next = safe_pages_list; | |
1761 | safe_pages_list = lp; | |
968808b8 | 1762 | } |
940864dd | 1763 | /* Mark the page as allocated */ |
7be98234 RW |
1764 | swsusp_set_page_forbidden(virt_to_page(lp)); |
1765 | swsusp_set_page_free(virt_to_page(lp)); | |
940864dd | 1766 | nr_pages--; |
968808b8 | 1767 | } |
940864dd RW |
1768 | /* Free the reserved safe pages so that chain_alloc() can use them */ |
1769 | while (sp_list) { | |
1770 | lp = sp_list->next; | |
1771 | free_image_page(sp_list, PG_UNSAFE_CLEAR); | |
1772 | sp_list = lp; | |
f577eb30 | 1773 | } |
940864dd RW |
1774 | return 0; |
1775 | ||
59a49335 | 1776 | Free: |
940864dd | 1777 | swsusp_free(); |
f577eb30 RW |
1778 | return error; |
1779 | } | |
1780 | ||
940864dd RW |
1781 | /** |
1782 | * get_buffer - compute the address that snapshot_write_next() should | |
1783 | * set for its caller to write to. | |
1784 | */ | |
1785 | ||
1786 | static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca) | |
968808b8 | 1787 | { |
940864dd RW |
1788 | struct pbe *pbe; |
1789 | struct page *page = pfn_to_page(memory_bm_next_pfn(bm)); | |
968808b8 | 1790 | |
8357376d RW |
1791 | if (PageHighMem(page)) |
1792 | return get_highmem_page_buffer(page, ca); | |
1793 | ||
7be98234 | 1794 | if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page)) |
940864dd RW |
1795 | /* We have allocated the "original" page frame and we can |
1796 | * use it directly to store the loaded page. | |
968808b8 | 1797 | */ |
940864dd RW |
1798 | return page_address(page); |
1799 | ||
1800 | /* The "original" page frame has not been allocated and we have to | |
1801 | * use a "safe" page frame to store the loaded page. | |
968808b8 | 1802 | */ |
940864dd RW |
1803 | pbe = chain_alloc(ca, sizeof(struct pbe)); |
1804 | if (!pbe) { | |
1805 | swsusp_free(); | |
1806 | return NULL; | |
1807 | } | |
8357376d RW |
1808 | pbe->orig_address = page_address(page); |
1809 | pbe->address = safe_pages_list; | |
940864dd RW |
1810 | safe_pages_list = safe_pages_list->next; |
1811 | pbe->next = restore_pblist; | |
1812 | restore_pblist = pbe; | |
8357376d | 1813 | return pbe->address; |
968808b8 RW |
1814 | } |
1815 | ||
f577eb30 RW |
1816 | /** |
1817 | * snapshot_write_next - used for writing the system memory snapshot. | |
1818 | * | |
1819 | * On the first call to it @handle should point to a zeroed | |
1820 | * snapshot_handle structure. The structure gets updated and a pointer | |
1821 | * to it should be passed to this function every next time. | |
1822 | * | |
1823 | * The @count parameter should contain the number of bytes the caller | |
1824 | * wants to write to the image. It must not be zero. | |
1825 | * | |
1826 | * On success the function returns a positive number. Then, the caller | |
1827 | * is allowed to write up to the returned number of bytes to the memory | |
1828 | * location computed by the data_of() macro. The number returned | |
1829 | * may be smaller than @count, but this only happens if the write would | |
1830 | * cross a page boundary otherwise. | |
1831 | * | |
1832 | * The function returns 0 to indicate the "end of file" condition, | |
1833 | * and a negative number is returned on error. In such cases the | |
1834 | * structure pointed to by @handle is not updated and should not be used | |
1835 | * any more. | |
1836 | */ | |
1837 | ||
1838 | int snapshot_write_next(struct snapshot_handle *handle, size_t count) | |
1839 | { | |
940864dd | 1840 | static struct chain_allocator ca; |
f577eb30 RW |
1841 | int error = 0; |
1842 | ||
940864dd | 1843 | /* Check if we have already loaded the entire image */ |
fb13a28b | 1844 | if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages) |
f577eb30 | 1845 | return 0; |
940864dd | 1846 | |
8357376d RW |
1847 | if (handle->offset == 0) { |
1848 | if (!buffer) | |
1849 | /* This makes the buffer be freed by swsusp_free() */ | |
1850 | buffer = get_image_page(GFP_ATOMIC, PG_ANY); | |
1851 | ||
f577eb30 RW |
1852 | if (!buffer) |
1853 | return -ENOMEM; | |
8357376d | 1854 | |
f577eb30 | 1855 | handle->buffer = buffer; |
8357376d | 1856 | } |
546e0d27 | 1857 | handle->sync_read = 1; |
fb13a28b | 1858 | if (handle->prev < handle->cur) { |
940864dd RW |
1859 | if (handle->prev == 0) { |
1860 | error = load_header(buffer); | |
1861 | if (error) | |
1862 | return error; | |
1863 | ||
1864 | error = memory_bm_create(©_bm, GFP_ATOMIC, PG_ANY); | |
f577eb30 RW |
1865 | if (error) |
1866 | return error; | |
940864dd | 1867 | |
f577eb30 | 1868 | } else if (handle->prev <= nr_meta_pages) { |
940864dd RW |
1869 | unpack_orig_pfns(buffer, ©_bm); |
1870 | if (handle->prev == nr_meta_pages) { | |
1871 | error = prepare_image(&orig_bm, ©_bm); | |
f577eb30 RW |
1872 | if (error) |
1873 | return error; | |
940864dd RW |
1874 | |
1875 | chain_init(&ca, GFP_ATOMIC, PG_SAFE); | |
1876 | memory_bm_position_reset(&orig_bm); | |
1877 | restore_pblist = NULL; | |
1878 | handle->buffer = get_buffer(&orig_bm, &ca); | |
546e0d27 | 1879 | handle->sync_read = 0; |
940864dd RW |
1880 | if (!handle->buffer) |
1881 | return -ENOMEM; | |
f577eb30 RW |
1882 | } |
1883 | } else { | |
8357376d | 1884 | copy_last_highmem_page(); |
940864dd | 1885 | handle->buffer = get_buffer(&orig_bm, &ca); |
8357376d RW |
1886 | if (handle->buffer != buffer) |
1887 | handle->sync_read = 0; | |
f577eb30 | 1888 | } |
fb13a28b | 1889 | handle->prev = handle->cur; |
f577eb30 | 1890 | } |
fb13a28b RW |
1891 | handle->buf_offset = handle->cur_offset; |
1892 | if (handle->cur_offset + count >= PAGE_SIZE) { | |
1893 | count = PAGE_SIZE - handle->cur_offset; | |
1894 | handle->cur_offset = 0; | |
1895 | handle->cur++; | |
f577eb30 | 1896 | } else { |
fb13a28b | 1897 | handle->cur_offset += count; |
f577eb30 RW |
1898 | } |
1899 | handle->offset += count; | |
1900 | return count; | |
1901 | } | |
1902 | ||
8357376d RW |
1903 | /** |
1904 | * snapshot_write_finalize - must be called after the last call to | |
1905 | * snapshot_write_next() in case the last page in the image happens | |
1906 | * to be a highmem page and its contents should be stored in the | |
1907 | * highmem. Additionally, it releases the memory that will not be | |
1908 | * used any more. | |
1909 | */ | |
1910 | ||
1911 | void snapshot_write_finalize(struct snapshot_handle *handle) | |
1912 | { | |
1913 | copy_last_highmem_page(); | |
1914 | /* Free only if we have loaded the image entirely */ | |
1915 | if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages) { | |
1916 | memory_bm_free(&orig_bm, PG_UNSAFE_CLEAR); | |
1917 | free_highmem_data(); | |
1918 | } | |
1919 | } | |
1920 | ||
f577eb30 RW |
1921 | int snapshot_image_loaded(struct snapshot_handle *handle) |
1922 | { | |
8357376d | 1923 | return !(!nr_copy_pages || !last_highmem_page_copied() || |
940864dd RW |
1924 | handle->cur <= nr_meta_pages + nr_copy_pages); |
1925 | } | |
1926 | ||
8357376d RW |
1927 | #ifdef CONFIG_HIGHMEM |
1928 | /* Assumes that @buf is ready and points to a "safe" page */ | |
1929 | static inline void | |
1930 | swap_two_pages_data(struct page *p1, struct page *p2, void *buf) | |
940864dd | 1931 | { |
8357376d RW |
1932 | void *kaddr1, *kaddr2; |
1933 | ||
1934 | kaddr1 = kmap_atomic(p1, KM_USER0); | |
1935 | kaddr2 = kmap_atomic(p2, KM_USER1); | |
1936 | memcpy(buf, kaddr1, PAGE_SIZE); | |
1937 | memcpy(kaddr1, kaddr2, PAGE_SIZE); | |
1938 | memcpy(kaddr2, buf, PAGE_SIZE); | |
1939 | kunmap_atomic(kaddr1, KM_USER0); | |
1940 | kunmap_atomic(kaddr2, KM_USER1); | |
1941 | } | |
1942 | ||
1943 | /** | |
1944 | * restore_highmem - for each highmem page that was allocated before | |
1945 | * the suspend and included in the suspend image, and also has been | |
1946 | * allocated by the "resume" kernel swap its current (ie. "before | |
1947 | * resume") contents with the previous (ie. "before suspend") one. | |
1948 | * | |
1949 | * If the resume eventually fails, we can call this function once | |
1950 | * again and restore the "before resume" highmem state. | |
1951 | */ | |
1952 | ||
1953 | int restore_highmem(void) | |
1954 | { | |
1955 | struct highmem_pbe *pbe = highmem_pblist; | |
1956 | void *buf; | |
1957 | ||
1958 | if (!pbe) | |
1959 | return 0; | |
1960 | ||
1961 | buf = get_image_page(GFP_ATOMIC, PG_SAFE); | |
1962 | if (!buf) | |
1963 | return -ENOMEM; | |
1964 | ||
1965 | while (pbe) { | |
1966 | swap_two_pages_data(pbe->copy_page, pbe->orig_page, buf); | |
1967 | pbe = pbe->next; | |
1968 | } | |
1969 | free_image_page(buf, PG_UNSAFE_CLEAR); | |
1970 | return 0; | |
f577eb30 | 1971 | } |
8357376d | 1972 | #endif /* CONFIG_HIGHMEM */ |