Commit | Line | Data |
---|---|---|
25761b6e | 1 | /* |
96bc7aec | 2 | * linux/kernel/power/snapshot.c |
25761b6e | 3 | * |
8357376d | 4 | * This file provides system snapshot/restore functionality for swsusp. |
25761b6e RW |
5 | * |
6 | * Copyright (C) 1998-2005 Pavel Machek <pavel@suse.cz> | |
8357376d | 7 | * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl> |
25761b6e | 8 | * |
8357376d | 9 | * This file is released under the GPLv2. |
25761b6e RW |
10 | * |
11 | */ | |
12 | ||
f577eb30 | 13 | #include <linux/version.h> |
25761b6e RW |
14 | #include <linux/module.h> |
15 | #include <linux/mm.h> | |
16 | #include <linux/suspend.h> | |
25761b6e | 17 | #include <linux/delay.h> |
25761b6e | 18 | #include <linux/bitops.h> |
25761b6e | 19 | #include <linux/spinlock.h> |
25761b6e | 20 | #include <linux/kernel.h> |
25761b6e RW |
21 | #include <linux/pm.h> |
22 | #include <linux/device.h> | |
74dfd666 | 23 | #include <linux/init.h> |
25761b6e RW |
24 | #include <linux/bootmem.h> |
25 | #include <linux/syscalls.h> | |
26 | #include <linux/console.h> | |
27 | #include <linux/highmem.h> | |
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 | |
0d83304c | 208 | * represent each blocks of bitmap in which information is stored. |
b788db79 RW |
209 | * |
210 | * struct memory_bitmap contains a pointer to the main list of zone | |
211 | * bitmap objects, a struct bm_position used for browsing the bitmap, | |
212 | * and a pointer to the list of pages used for allocating all of the | |
213 | * zone bitmap objects and bitmap block objects. | |
214 | * | |
215 | * NOTE: It has to be possible to lay out the bitmap in memory | |
216 | * using only allocations of order 0. Additionally, the bitmap is | |
217 | * designed to work with arbitrary number of zones (this is over the | |
218 | * top for now, but let's avoid making unnecessary assumptions ;-). | |
219 | * | |
220 | * struct zone_bitmap contains a pointer to a list of bitmap block | |
221 | * objects and a pointer to the bitmap block object that has been | |
222 | * most recently used for setting bits. Additionally, it contains the | |
223 | * pfns that correspond to the start and end of the represented zone. | |
224 | * | |
225 | * struct bm_block contains a pointer to the memory page in which | |
0d83304c AM |
226 | * information is stored (in the form of a block of bitmap) |
227 | * It also contains the pfns that correspond to the start and end of | |
228 | * the represented memory area. | |
b788db79 RW |
229 | */ |
230 | ||
231 | #define BM_END_OF_MAP (~0UL) | |
232 | ||
b788db79 RW |
233 | #define BM_BITS_PER_BLOCK (PAGE_SIZE << 3) |
234 | ||
235 | struct bm_block { | |
236 | struct bm_block *next; /* next element of the list */ | |
237 | unsigned long start_pfn; /* pfn represented by the first bit */ | |
238 | unsigned long end_pfn; /* pfn represented by the last bit plus 1 */ | |
0d83304c | 239 | unsigned long *data; /* bitmap representing pages */ |
b788db79 RW |
240 | }; |
241 | ||
0d83304c AM |
242 | static inline unsigned long bm_block_bits(struct bm_block *bb) |
243 | { | |
244 | return bb->end_pfn - bb->start_pfn; | |
245 | } | |
246 | ||
b788db79 RW |
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; | |
b788db79 RW |
260 | int bit; |
261 | }; | |
262 | ||
263 | struct memory_bitmap { | |
264 | struct zone_bitmap *zone_bm_list; /* list of zone bitmaps */ | |
265 | struct linked_page *p_list; /* list of pages used to store zone | |
266 | * bitmap objects and bitmap block | |
267 | * objects | |
268 | */ | |
269 | struct bm_position cur; /* most recently used bit position */ | |
270 | }; | |
271 | ||
272 | /* Functions that operate on memory bitmaps */ | |
273 | ||
b788db79 RW |
274 | static void memory_bm_position_reset(struct memory_bitmap *bm) |
275 | { | |
276 | struct zone_bitmap *zone_bm; | |
277 | ||
278 | zone_bm = bm->zone_bm_list; | |
279 | bm->cur.zone_bm = zone_bm; | |
280 | bm->cur.block = zone_bm->bm_blocks; | |
0d83304c | 281 | bm->cur.bit = 0; |
b788db79 RW |
282 | } |
283 | ||
284 | static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free); | |
285 | ||
286 | /** | |
287 | * create_bm_block_list - create a list of block bitmap objects | |
288 | */ | |
289 | ||
290 | static inline struct bm_block * | |
291 | create_bm_block_list(unsigned int nr_blocks, struct chain_allocator *ca) | |
292 | { | |
293 | struct bm_block *bblist = NULL; | |
294 | ||
295 | while (nr_blocks-- > 0) { | |
296 | struct bm_block *bb; | |
297 | ||
298 | bb = chain_alloc(ca, sizeof(struct bm_block)); | |
299 | if (!bb) | |
300 | return NULL; | |
301 | ||
302 | bb->next = bblist; | |
303 | bblist = bb; | |
304 | } | |
305 | return bblist; | |
306 | } | |
307 | ||
308 | /** | |
309 | * create_zone_bm_list - create a list of zone bitmap objects | |
310 | */ | |
311 | ||
312 | static inline struct zone_bitmap * | |
313 | create_zone_bm_list(unsigned int nr_zones, struct chain_allocator *ca) | |
314 | { | |
315 | struct zone_bitmap *zbmlist = NULL; | |
316 | ||
317 | while (nr_zones-- > 0) { | |
318 | struct zone_bitmap *zbm; | |
319 | ||
320 | zbm = chain_alloc(ca, sizeof(struct zone_bitmap)); | |
321 | if (!zbm) | |
322 | return NULL; | |
323 | ||
324 | zbm->next = zbmlist; | |
325 | zbmlist = zbm; | |
326 | } | |
327 | return zbmlist; | |
328 | } | |
329 | ||
330 | /** | |
331 | * memory_bm_create - allocate memory for a memory bitmap | |
332 | */ | |
333 | ||
334 | static int | |
335 | memory_bm_create(struct memory_bitmap *bm, gfp_t gfp_mask, int safe_needed) | |
336 | { | |
337 | struct chain_allocator ca; | |
338 | struct zone *zone; | |
339 | struct zone_bitmap *zone_bm; | |
340 | struct bm_block *bb; | |
341 | unsigned int nr; | |
342 | ||
343 | chain_init(&ca, gfp_mask, safe_needed); | |
344 | ||
345 | /* Compute the number of zones */ | |
346 | nr = 0; | |
8357376d RW |
347 | for_each_zone(zone) |
348 | if (populated_zone(zone)) | |
b788db79 RW |
349 | nr++; |
350 | ||
351 | /* Allocate the list of zones bitmap objects */ | |
352 | zone_bm = create_zone_bm_list(nr, &ca); | |
353 | bm->zone_bm_list = zone_bm; | |
354 | if (!zone_bm) { | |
355 | chain_free(&ca, PG_UNSAFE_CLEAR); | |
356 | return -ENOMEM; | |
357 | } | |
358 | ||
359 | /* Initialize the zone bitmap objects */ | |
8357376d | 360 | for_each_zone(zone) { |
b788db79 RW |
361 | unsigned long pfn; |
362 | ||
8357376d | 363 | if (!populated_zone(zone)) |
b788db79 RW |
364 | continue; |
365 | ||
366 | zone_bm->start_pfn = zone->zone_start_pfn; | |
367 | zone_bm->end_pfn = zone->zone_start_pfn + zone->spanned_pages; | |
368 | /* Allocate the list of bitmap block objects */ | |
369 | nr = DIV_ROUND_UP(zone->spanned_pages, BM_BITS_PER_BLOCK); | |
370 | bb = create_bm_block_list(nr, &ca); | |
371 | zone_bm->bm_blocks = bb; | |
372 | zone_bm->cur_block = bb; | |
373 | if (!bb) | |
374 | goto Free; | |
375 | ||
376 | nr = zone->spanned_pages; | |
377 | pfn = zone->zone_start_pfn; | |
378 | /* Initialize the bitmap block objects */ | |
379 | while (bb) { | |
380 | unsigned long *ptr; | |
381 | ||
8357376d | 382 | ptr = get_image_page(gfp_mask, safe_needed); |
b788db79 RW |
383 | bb->data = ptr; |
384 | if (!ptr) | |
385 | goto Free; | |
386 | ||
387 | bb->start_pfn = pfn; | |
388 | if (nr >= BM_BITS_PER_BLOCK) { | |
389 | pfn += BM_BITS_PER_BLOCK; | |
b788db79 RW |
390 | nr -= BM_BITS_PER_BLOCK; |
391 | } else { | |
392 | /* This is executed only once in the loop */ | |
393 | pfn += nr; | |
b788db79 RW |
394 | } |
395 | bb->end_pfn = pfn; | |
396 | bb = bb->next; | |
397 | } | |
398 | zone_bm = zone_bm->next; | |
399 | } | |
400 | bm->p_list = ca.chain; | |
401 | memory_bm_position_reset(bm); | |
402 | return 0; | |
403 | ||
59a49335 | 404 | Free: |
b788db79 RW |
405 | bm->p_list = ca.chain; |
406 | memory_bm_free(bm, PG_UNSAFE_CLEAR); | |
407 | return -ENOMEM; | |
408 | } | |
409 | ||
410 | /** | |
411 | * memory_bm_free - free memory occupied by the memory bitmap @bm | |
412 | */ | |
413 | ||
414 | static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free) | |
415 | { | |
416 | struct zone_bitmap *zone_bm; | |
417 | ||
418 | /* Free the list of bit blocks for each zone_bitmap object */ | |
419 | zone_bm = bm->zone_bm_list; | |
420 | while (zone_bm) { | |
421 | struct bm_block *bb; | |
422 | ||
423 | bb = zone_bm->bm_blocks; | |
424 | while (bb) { | |
425 | if (bb->data) | |
426 | free_image_page(bb->data, clear_nosave_free); | |
427 | bb = bb->next; | |
428 | } | |
429 | zone_bm = zone_bm->next; | |
430 | } | |
431 | free_list_of_pages(bm->p_list, clear_nosave_free); | |
432 | bm->zone_bm_list = NULL; | |
433 | } | |
434 | ||
435 | /** | |
74dfd666 | 436 | * memory_bm_find_bit - find the bit in the bitmap @bm that corresponds |
b788db79 RW |
437 | * to given pfn. The cur_zone_bm member of @bm and the cur_block member |
438 | * of @bm->cur_zone_bm are updated. | |
b788db79 RW |
439 | */ |
440 | ||
a82f7119 | 441 | static int memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn, |
74dfd666 | 442 | void **addr, unsigned int *bit_nr) |
b788db79 RW |
443 | { |
444 | struct zone_bitmap *zone_bm; | |
445 | struct bm_block *bb; | |
446 | ||
447 | /* Check if the pfn is from the current zone */ | |
448 | zone_bm = bm->cur.zone_bm; | |
449 | if (pfn < zone_bm->start_pfn || pfn >= zone_bm->end_pfn) { | |
450 | zone_bm = bm->zone_bm_list; | |
451 | /* We don't assume that the zones are sorted by pfns */ | |
452 | while (pfn < zone_bm->start_pfn || pfn >= zone_bm->end_pfn) { | |
453 | zone_bm = zone_bm->next; | |
74dfd666 | 454 | |
a82f7119 RW |
455 | if (!zone_bm) |
456 | return -EFAULT; | |
b788db79 RW |
457 | } |
458 | bm->cur.zone_bm = zone_bm; | |
459 | } | |
460 | /* Check if the pfn corresponds to the current bitmap block */ | |
461 | bb = zone_bm->cur_block; | |
462 | if (pfn < bb->start_pfn) | |
463 | bb = zone_bm->bm_blocks; | |
464 | ||
465 | while (pfn >= bb->end_pfn) { | |
466 | bb = bb->next; | |
74dfd666 RW |
467 | |
468 | BUG_ON(!bb); | |
b788db79 RW |
469 | } |
470 | zone_bm->cur_block = bb; | |
471 | pfn -= bb->start_pfn; | |
0d83304c AM |
472 | *bit_nr = pfn; |
473 | *addr = bb->data; | |
a82f7119 | 474 | return 0; |
74dfd666 RW |
475 | } |
476 | ||
477 | static void memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn) | |
478 | { | |
479 | void *addr; | |
480 | unsigned int bit; | |
a82f7119 | 481 | int error; |
74dfd666 | 482 | |
a82f7119 RW |
483 | error = memory_bm_find_bit(bm, pfn, &addr, &bit); |
484 | BUG_ON(error); | |
74dfd666 RW |
485 | set_bit(bit, addr); |
486 | } | |
487 | ||
a82f7119 RW |
488 | static int mem_bm_set_bit_check(struct memory_bitmap *bm, unsigned long pfn) |
489 | { | |
490 | void *addr; | |
491 | unsigned int bit; | |
492 | int error; | |
493 | ||
494 | error = memory_bm_find_bit(bm, pfn, &addr, &bit); | |
495 | if (!error) | |
496 | set_bit(bit, addr); | |
497 | return error; | |
498 | } | |
499 | ||
74dfd666 RW |
500 | static void memory_bm_clear_bit(struct memory_bitmap *bm, unsigned long pfn) |
501 | { | |
502 | void *addr; | |
503 | unsigned int bit; | |
a82f7119 | 504 | int error; |
74dfd666 | 505 | |
a82f7119 RW |
506 | error = memory_bm_find_bit(bm, pfn, &addr, &bit); |
507 | BUG_ON(error); | |
74dfd666 RW |
508 | clear_bit(bit, addr); |
509 | } | |
510 | ||
511 | static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn) | |
512 | { | |
513 | void *addr; | |
514 | unsigned int bit; | |
a82f7119 | 515 | int error; |
74dfd666 | 516 | |
a82f7119 RW |
517 | error = memory_bm_find_bit(bm, pfn, &addr, &bit); |
518 | BUG_ON(error); | |
74dfd666 | 519 | return test_bit(bit, addr); |
b788db79 RW |
520 | } |
521 | ||
b788db79 RW |
522 | /** |
523 | * memory_bm_next_pfn - find the pfn that corresponds to the next set bit | |
524 | * in the bitmap @bm. If the pfn cannot be found, BM_END_OF_MAP is | |
525 | * returned. | |
526 | * | |
527 | * It is required to run memory_bm_position_reset() before the first call to | |
528 | * this function. | |
529 | */ | |
530 | ||
531 | static unsigned long memory_bm_next_pfn(struct memory_bitmap *bm) | |
532 | { | |
533 | struct zone_bitmap *zone_bm; | |
534 | struct bm_block *bb; | |
b788db79 RW |
535 | int bit; |
536 | ||
537 | do { | |
538 | bb = bm->cur.block; | |
539 | do { | |
b788db79 | 540 | bit = bm->cur.bit; |
0d83304c AM |
541 | bit = find_next_bit(bb->data, bm_block_bits(bb), bit); |
542 | if (bit < bm_block_bits(bb)) | |
543 | goto Return_pfn; | |
544 | ||
b788db79 RW |
545 | bb = bb->next; |
546 | bm->cur.block = bb; | |
0d83304c | 547 | bm->cur.bit = 0; |
b788db79 RW |
548 | } while (bb); |
549 | zone_bm = bm->cur.zone_bm->next; | |
550 | if (zone_bm) { | |
551 | bm->cur.zone_bm = zone_bm; | |
552 | bm->cur.block = zone_bm->bm_blocks; | |
0d83304c | 553 | bm->cur.bit = 0; |
b788db79 RW |
554 | } |
555 | } while (zone_bm); | |
556 | memory_bm_position_reset(bm); | |
557 | return BM_END_OF_MAP; | |
558 | ||
59a49335 | 559 | Return_pfn: |
0d83304c AM |
560 | bm->cur.bit = bit + 1; |
561 | return bb->start_pfn + bit; | |
b788db79 RW |
562 | } |
563 | ||
74dfd666 RW |
564 | /** |
565 | * This structure represents a range of page frames the contents of which | |
566 | * should not be saved during the suspend. | |
567 | */ | |
568 | ||
569 | struct nosave_region { | |
570 | struct list_head list; | |
571 | unsigned long start_pfn; | |
572 | unsigned long end_pfn; | |
573 | }; | |
574 | ||
575 | static LIST_HEAD(nosave_regions); | |
576 | ||
577 | /** | |
578 | * register_nosave_region - register a range of page frames the contents | |
579 | * of which should not be saved during the suspend (to be used in the early | |
580 | * initialization code) | |
581 | */ | |
582 | ||
583 | void __init | |
940d67f6 JB |
584 | __register_nosave_region(unsigned long start_pfn, unsigned long end_pfn, |
585 | int use_kmalloc) | |
74dfd666 RW |
586 | { |
587 | struct nosave_region *region; | |
588 | ||
589 | if (start_pfn >= end_pfn) | |
590 | return; | |
591 | ||
592 | if (!list_empty(&nosave_regions)) { | |
593 | /* Try to extend the previous region (they should be sorted) */ | |
594 | region = list_entry(nosave_regions.prev, | |
595 | struct nosave_region, list); | |
596 | if (region->end_pfn == start_pfn) { | |
597 | region->end_pfn = end_pfn; | |
598 | goto Report; | |
599 | } | |
600 | } | |
940d67f6 JB |
601 | if (use_kmalloc) { |
602 | /* during init, this shouldn't fail */ | |
603 | region = kmalloc(sizeof(struct nosave_region), GFP_KERNEL); | |
604 | BUG_ON(!region); | |
605 | } else | |
606 | /* This allocation cannot fail */ | |
607 | region = alloc_bootmem_low(sizeof(struct nosave_region)); | |
74dfd666 RW |
608 | region->start_pfn = start_pfn; |
609 | region->end_pfn = end_pfn; | |
610 | list_add_tail(®ion->list, &nosave_regions); | |
611 | Report: | |
23976728 | 612 | printk(KERN_INFO "PM: Registered nosave memory: %016lx - %016lx\n", |
74dfd666 RW |
613 | start_pfn << PAGE_SHIFT, end_pfn << PAGE_SHIFT); |
614 | } | |
615 | ||
616 | /* | |
617 | * Set bits in this map correspond to the page frames the contents of which | |
618 | * should not be saved during the suspend. | |
619 | */ | |
620 | static struct memory_bitmap *forbidden_pages_map; | |
621 | ||
622 | /* Set bits in this map correspond to free page frames. */ | |
623 | static struct memory_bitmap *free_pages_map; | |
624 | ||
625 | /* | |
626 | * Each page frame allocated for creating the image is marked by setting the | |
627 | * corresponding bits in forbidden_pages_map and free_pages_map simultaneously | |
628 | */ | |
629 | ||
630 | void swsusp_set_page_free(struct page *page) | |
631 | { | |
632 | if (free_pages_map) | |
633 | memory_bm_set_bit(free_pages_map, page_to_pfn(page)); | |
634 | } | |
635 | ||
636 | static int swsusp_page_is_free(struct page *page) | |
637 | { | |
638 | return free_pages_map ? | |
639 | memory_bm_test_bit(free_pages_map, page_to_pfn(page)) : 0; | |
640 | } | |
641 | ||
642 | void swsusp_unset_page_free(struct page *page) | |
643 | { | |
644 | if (free_pages_map) | |
645 | memory_bm_clear_bit(free_pages_map, page_to_pfn(page)); | |
646 | } | |
647 | ||
648 | static void swsusp_set_page_forbidden(struct page *page) | |
649 | { | |
650 | if (forbidden_pages_map) | |
651 | memory_bm_set_bit(forbidden_pages_map, page_to_pfn(page)); | |
652 | } | |
653 | ||
654 | int swsusp_page_is_forbidden(struct page *page) | |
655 | { | |
656 | return forbidden_pages_map ? | |
657 | memory_bm_test_bit(forbidden_pages_map, page_to_pfn(page)) : 0; | |
658 | } | |
659 | ||
660 | static void swsusp_unset_page_forbidden(struct page *page) | |
661 | { | |
662 | if (forbidden_pages_map) | |
663 | memory_bm_clear_bit(forbidden_pages_map, page_to_pfn(page)); | |
664 | } | |
665 | ||
666 | /** | |
667 | * mark_nosave_pages - set bits corresponding to the page frames the | |
668 | * contents of which should not be saved in a given bitmap. | |
669 | */ | |
670 | ||
671 | static void mark_nosave_pages(struct memory_bitmap *bm) | |
672 | { | |
673 | struct nosave_region *region; | |
674 | ||
675 | if (list_empty(&nosave_regions)) | |
676 | return; | |
677 | ||
678 | list_for_each_entry(region, &nosave_regions, list) { | |
679 | unsigned long pfn; | |
680 | ||
23976728 | 681 | pr_debug("PM: Marking nosave pages: %016lx - %016lx\n", |
74dfd666 RW |
682 | region->start_pfn << PAGE_SHIFT, |
683 | region->end_pfn << PAGE_SHIFT); | |
684 | ||
685 | for (pfn = region->start_pfn; pfn < region->end_pfn; pfn++) | |
a82f7119 RW |
686 | if (pfn_valid(pfn)) { |
687 | /* | |
688 | * It is safe to ignore the result of | |
689 | * mem_bm_set_bit_check() here, since we won't | |
690 | * touch the PFNs for which the error is | |
691 | * returned anyway. | |
692 | */ | |
693 | mem_bm_set_bit_check(bm, pfn); | |
694 | } | |
74dfd666 RW |
695 | } |
696 | } | |
697 | ||
698 | /** | |
699 | * create_basic_memory_bitmaps - create bitmaps needed for marking page | |
700 | * frames that should not be saved and free page frames. The pointers | |
701 | * forbidden_pages_map and free_pages_map are only modified if everything | |
702 | * goes well, because we don't want the bits to be used before both bitmaps | |
703 | * are set up. | |
704 | */ | |
705 | ||
706 | int create_basic_memory_bitmaps(void) | |
707 | { | |
708 | struct memory_bitmap *bm1, *bm2; | |
709 | int error = 0; | |
710 | ||
711 | BUG_ON(forbidden_pages_map || free_pages_map); | |
712 | ||
0709db60 | 713 | bm1 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL); |
74dfd666 RW |
714 | if (!bm1) |
715 | return -ENOMEM; | |
716 | ||
0709db60 | 717 | error = memory_bm_create(bm1, GFP_KERNEL, PG_ANY); |
74dfd666 RW |
718 | if (error) |
719 | goto Free_first_object; | |
720 | ||
0709db60 | 721 | bm2 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL); |
74dfd666 RW |
722 | if (!bm2) |
723 | goto Free_first_bitmap; | |
724 | ||
0709db60 | 725 | error = memory_bm_create(bm2, GFP_KERNEL, PG_ANY); |
74dfd666 RW |
726 | if (error) |
727 | goto Free_second_object; | |
728 | ||
729 | forbidden_pages_map = bm1; | |
730 | free_pages_map = bm2; | |
731 | mark_nosave_pages(forbidden_pages_map); | |
732 | ||
23976728 | 733 | pr_debug("PM: Basic memory bitmaps created\n"); |
74dfd666 RW |
734 | |
735 | return 0; | |
736 | ||
737 | Free_second_object: | |
738 | kfree(bm2); | |
739 | Free_first_bitmap: | |
740 | memory_bm_free(bm1, PG_UNSAFE_CLEAR); | |
741 | Free_first_object: | |
742 | kfree(bm1); | |
743 | return -ENOMEM; | |
744 | } | |
745 | ||
746 | /** | |
747 | * free_basic_memory_bitmaps - free memory bitmaps allocated by | |
748 | * create_basic_memory_bitmaps(). The auxiliary pointers are necessary | |
749 | * so that the bitmaps themselves are not referred to while they are being | |
750 | * freed. | |
751 | */ | |
752 | ||
753 | void free_basic_memory_bitmaps(void) | |
754 | { | |
755 | struct memory_bitmap *bm1, *bm2; | |
756 | ||
757 | BUG_ON(!(forbidden_pages_map && free_pages_map)); | |
758 | ||
759 | bm1 = forbidden_pages_map; | |
760 | bm2 = free_pages_map; | |
761 | forbidden_pages_map = NULL; | |
762 | free_pages_map = NULL; | |
763 | memory_bm_free(bm1, PG_UNSAFE_CLEAR); | |
764 | kfree(bm1); | |
765 | memory_bm_free(bm2, PG_UNSAFE_CLEAR); | |
766 | kfree(bm2); | |
767 | ||
23976728 | 768 | pr_debug("PM: Basic memory bitmaps freed\n"); |
74dfd666 RW |
769 | } |
770 | ||
b788db79 RW |
771 | /** |
772 | * snapshot_additional_pages - estimate the number of additional pages | |
773 | * be needed for setting up the suspend image data structures for given | |
774 | * zone (usually the returned value is greater than the exact number) | |
775 | */ | |
776 | ||
777 | unsigned int snapshot_additional_pages(struct zone *zone) | |
778 | { | |
779 | unsigned int res; | |
780 | ||
781 | res = DIV_ROUND_UP(zone->spanned_pages, BM_BITS_PER_BLOCK); | |
782 | res += DIV_ROUND_UP(res * sizeof(struct bm_block), PAGE_SIZE); | |
8357376d | 783 | return 2 * res; |
b788db79 RW |
784 | } |
785 | ||
8357376d RW |
786 | #ifdef CONFIG_HIGHMEM |
787 | /** | |
788 | * count_free_highmem_pages - compute the total number of free highmem | |
789 | * pages, system-wide. | |
790 | */ | |
791 | ||
792 | static unsigned int count_free_highmem_pages(void) | |
793 | { | |
794 | struct zone *zone; | |
795 | unsigned int cnt = 0; | |
796 | ||
797 | for_each_zone(zone) | |
798 | if (populated_zone(zone) && is_highmem(zone)) | |
d23ad423 | 799 | cnt += zone_page_state(zone, NR_FREE_PAGES); |
8357376d RW |
800 | |
801 | return cnt; | |
802 | } | |
803 | ||
804 | /** | |
805 | * saveable_highmem_page - Determine whether a highmem page should be | |
806 | * included in the suspend image. | |
807 | * | |
808 | * We should save the page if it isn't Nosave or NosaveFree, or Reserved, | |
809 | * and it isn't a part of a free chunk of pages. | |
810 | */ | |
811 | ||
812 | static struct page *saveable_highmem_page(unsigned long pfn) | |
813 | { | |
814 | struct page *page; | |
815 | ||
816 | if (!pfn_valid(pfn)) | |
817 | return NULL; | |
818 | ||
819 | page = pfn_to_page(pfn); | |
820 | ||
821 | BUG_ON(!PageHighMem(page)); | |
822 | ||
7be98234 RW |
823 | if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page) || |
824 | PageReserved(page)) | |
8357376d RW |
825 | return NULL; |
826 | ||
827 | return page; | |
828 | } | |
829 | ||
830 | /** | |
831 | * count_highmem_pages - compute the total number of saveable highmem | |
832 | * pages. | |
833 | */ | |
834 | ||
835 | unsigned int count_highmem_pages(void) | |
836 | { | |
837 | struct zone *zone; | |
838 | unsigned int n = 0; | |
839 | ||
840 | for_each_zone(zone) { | |
841 | unsigned long pfn, max_zone_pfn; | |
842 | ||
843 | if (!is_highmem(zone)) | |
844 | continue; | |
845 | ||
846 | mark_free_pages(zone); | |
847 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; | |
848 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
849 | if (saveable_highmem_page(pfn)) | |
850 | n++; | |
851 | } | |
852 | return n; | |
853 | } | |
854 | #else | |
855 | static inline void *saveable_highmem_page(unsigned long pfn) { return NULL; } | |
8357376d RW |
856 | #endif /* CONFIG_HIGHMEM */ |
857 | ||
25761b6e | 858 | /** |
8a235efa RW |
859 | * saveable_page - Determine whether a non-highmem page should be included |
860 | * in the suspend image. | |
25761b6e | 861 | * |
8357376d RW |
862 | * We should save the page if it isn't Nosave, and is not in the range |
863 | * of pages statically defined as 'unsaveable', and it isn't a part of | |
864 | * a free chunk of pages. | |
25761b6e RW |
865 | */ |
866 | ||
ae83c5ee | 867 | static struct page *saveable_page(unsigned long pfn) |
25761b6e | 868 | { |
de491861 | 869 | struct page *page; |
25761b6e RW |
870 | |
871 | if (!pfn_valid(pfn)) | |
ae83c5ee | 872 | return NULL; |
25761b6e RW |
873 | |
874 | page = pfn_to_page(pfn); | |
ae83c5ee | 875 | |
8357376d RW |
876 | BUG_ON(PageHighMem(page)); |
877 | ||
7be98234 | 878 | if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page)) |
ae83c5ee | 879 | return NULL; |
8357376d | 880 | |
8a235efa RW |
881 | if (PageReserved(page) |
882 | && (!kernel_page_present(page) || pfn_is_nosave(pfn))) | |
ae83c5ee | 883 | return NULL; |
25761b6e | 884 | |
ae83c5ee | 885 | return page; |
25761b6e RW |
886 | } |
887 | ||
8357376d RW |
888 | /** |
889 | * count_data_pages - compute the total number of saveable non-highmem | |
890 | * pages. | |
891 | */ | |
892 | ||
72a97e08 | 893 | unsigned int count_data_pages(void) |
25761b6e RW |
894 | { |
895 | struct zone *zone; | |
ae83c5ee | 896 | unsigned long pfn, max_zone_pfn; |
dc19d507 | 897 | unsigned int n = 0; |
25761b6e | 898 | |
8357376d | 899 | for_each_zone(zone) { |
25761b6e RW |
900 | if (is_highmem(zone)) |
901 | continue; | |
8357376d | 902 | |
25761b6e | 903 | mark_free_pages(zone); |
ae83c5ee RW |
904 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
905 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
8357376d RW |
906 | if(saveable_page(pfn)) |
907 | n++; | |
25761b6e | 908 | } |
a0f49651 | 909 | return n; |
25761b6e RW |
910 | } |
911 | ||
8357376d RW |
912 | /* This is needed, because copy_page and memcpy are not usable for copying |
913 | * task structs. | |
914 | */ | |
915 | static inline void do_copy_page(long *dst, long *src) | |
f623f0db RW |
916 | { |
917 | int n; | |
918 | ||
f623f0db RW |
919 | for (n = PAGE_SIZE / sizeof(long); n; n--) |
920 | *dst++ = *src++; | |
921 | } | |
922 | ||
8a235efa RW |
923 | |
924 | /** | |
925 | * safe_copy_page - check if the page we are going to copy is marked as | |
926 | * present in the kernel page tables (this always is the case if | |
927 | * CONFIG_DEBUG_PAGEALLOC is not set and in that case | |
928 | * kernel_page_present() always returns 'true'). | |
929 | */ | |
930 | static void safe_copy_page(void *dst, struct page *s_page) | |
931 | { | |
932 | if (kernel_page_present(s_page)) { | |
933 | do_copy_page(dst, page_address(s_page)); | |
934 | } else { | |
935 | kernel_map_pages(s_page, 1, 1); | |
936 | do_copy_page(dst, page_address(s_page)); | |
937 | kernel_map_pages(s_page, 1, 0); | |
938 | } | |
939 | } | |
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 | ||
8a235efa | 950 | static void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) |
8357376d RW |
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 { | |
8357376d RW |
964 | if (PageHighMem(d_page)) { |
965 | /* Page pointed to by src may contain some kernel | |
966 | * data modified by kmap_atomic() | |
967 | */ | |
8a235efa | 968 | safe_copy_page(buffer, s_page); |
8357376d RW |
969 | dst = kmap_atomic(pfn_to_page(dst_pfn), KM_USER0); |
970 | memcpy(dst, buffer, PAGE_SIZE); | |
971 | kunmap_atomic(dst, KM_USER0); | |
972 | } else { | |
8a235efa | 973 | safe_copy_page(page_address(d_page), s_page); |
8357376d RW |
974 | } |
975 | } | |
976 | } | |
977 | #else | |
978 | #define page_is_saveable(zone, pfn) saveable_page(pfn) | |
979 | ||
8a235efa | 980 | static inline void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) |
8357376d | 981 | { |
8a235efa RW |
982 | safe_copy_page(page_address(pfn_to_page(dst_pfn)), |
983 | pfn_to_page(src_pfn)); | |
8357376d RW |
984 | } |
985 | #endif /* CONFIG_HIGHMEM */ | |
986 | ||
b788db79 RW |
987 | static void |
988 | copy_data_pages(struct memory_bitmap *copy_bm, struct memory_bitmap *orig_bm) | |
25761b6e RW |
989 | { |
990 | struct zone *zone; | |
b788db79 | 991 | unsigned long pfn; |
25761b6e | 992 | |
8357376d | 993 | for_each_zone(zone) { |
b788db79 RW |
994 | unsigned long max_zone_pfn; |
995 | ||
25761b6e | 996 | mark_free_pages(zone); |
ae83c5ee | 997 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
b788db79 | 998 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) |
8357376d | 999 | if (page_is_saveable(zone, pfn)) |
b788db79 | 1000 | memory_bm_set_bit(orig_bm, pfn); |
25761b6e | 1001 | } |
b788db79 RW |
1002 | memory_bm_position_reset(orig_bm); |
1003 | memory_bm_position_reset(copy_bm); | |
df7c4872 | 1004 | for(;;) { |
b788db79 | 1005 | pfn = memory_bm_next_pfn(orig_bm); |
df7c4872 FW |
1006 | if (unlikely(pfn == BM_END_OF_MAP)) |
1007 | break; | |
1008 | copy_data_page(memory_bm_next_pfn(copy_bm), pfn); | |
1009 | } | |
25761b6e RW |
1010 | } |
1011 | ||
8357376d RW |
1012 | /* Total number of image pages */ |
1013 | static unsigned int nr_copy_pages; | |
1014 | /* Number of pages needed for saving the original pfns of the image pages */ | |
1015 | static unsigned int nr_meta_pages; | |
1016 | ||
25761b6e | 1017 | /** |
940864dd | 1018 | * swsusp_free - free pages allocated for the suspend. |
cd560bb2 | 1019 | * |
940864dd RW |
1020 | * Suspend pages are alocated before the atomic copy is made, so we |
1021 | * need to release them after the resume. | |
25761b6e RW |
1022 | */ |
1023 | ||
1024 | void swsusp_free(void) | |
1025 | { | |
1026 | struct zone *zone; | |
ae83c5ee | 1027 | unsigned long pfn, max_zone_pfn; |
25761b6e RW |
1028 | |
1029 | for_each_zone(zone) { | |
ae83c5ee RW |
1030 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
1031 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
1032 | if (pfn_valid(pfn)) { | |
1033 | struct page *page = pfn_to_page(pfn); | |
1034 | ||
7be98234 RW |
1035 | if (swsusp_page_is_forbidden(page) && |
1036 | swsusp_page_is_free(page)) { | |
1037 | swsusp_unset_page_forbidden(page); | |
1038 | swsusp_unset_page_free(page); | |
8357376d | 1039 | __free_page(page); |
25761b6e RW |
1040 | } |
1041 | } | |
1042 | } | |
f577eb30 RW |
1043 | nr_copy_pages = 0; |
1044 | nr_meta_pages = 0; | |
75534b50 | 1045 | restore_pblist = NULL; |
6e1819d6 | 1046 | buffer = NULL; |
25761b6e RW |
1047 | } |
1048 | ||
8357376d RW |
1049 | #ifdef CONFIG_HIGHMEM |
1050 | /** | |
1051 | * count_pages_for_highmem - compute the number of non-highmem pages | |
1052 | * that will be necessary for creating copies of highmem pages. | |
1053 | */ | |
1054 | ||
1055 | static unsigned int count_pages_for_highmem(unsigned int nr_highmem) | |
1056 | { | |
1057 | unsigned int free_highmem = count_free_highmem_pages(); | |
1058 | ||
1059 | if (free_highmem >= nr_highmem) | |
1060 | nr_highmem = 0; | |
1061 | else | |
1062 | nr_highmem -= free_highmem; | |
1063 | ||
1064 | return nr_highmem; | |
1065 | } | |
1066 | #else | |
1067 | static unsigned int | |
1068 | count_pages_for_highmem(unsigned int nr_highmem) { return 0; } | |
1069 | #endif /* CONFIG_HIGHMEM */ | |
25761b6e RW |
1070 | |
1071 | /** | |
8357376d RW |
1072 | * enough_free_mem - Make sure we have enough free memory for the |
1073 | * snapshot image. | |
25761b6e RW |
1074 | */ |
1075 | ||
8357376d | 1076 | static int enough_free_mem(unsigned int nr_pages, unsigned int nr_highmem) |
25761b6e | 1077 | { |
e5e2fa78 | 1078 | struct zone *zone; |
940864dd | 1079 | unsigned int free = 0, meta = 0; |
e5e2fa78 | 1080 | |
8357376d RW |
1081 | for_each_zone(zone) { |
1082 | meta += snapshot_additional_pages(zone); | |
1083 | if (!is_highmem(zone)) | |
d23ad423 | 1084 | free += zone_page_state(zone, NR_FREE_PAGES); |
8357376d | 1085 | } |
940864dd | 1086 | |
8357376d | 1087 | nr_pages += count_pages_for_highmem(nr_highmem); |
23976728 | 1088 | pr_debug("PM: Normal pages needed: %u + %u + %u, available pages: %u\n", |
940864dd RW |
1089 | nr_pages, PAGES_FOR_IO, meta, free); |
1090 | ||
1091 | return free > nr_pages + PAGES_FOR_IO + meta; | |
25761b6e RW |
1092 | } |
1093 | ||
8357376d RW |
1094 | #ifdef CONFIG_HIGHMEM |
1095 | /** | |
1096 | * get_highmem_buffer - if there are some highmem pages in the suspend | |
1097 | * image, we may need the buffer to copy them and/or load their data. | |
1098 | */ | |
1099 | ||
1100 | static inline int get_highmem_buffer(int safe_needed) | |
1101 | { | |
1102 | buffer = get_image_page(GFP_ATOMIC | __GFP_COLD, safe_needed); | |
1103 | return buffer ? 0 : -ENOMEM; | |
1104 | } | |
1105 | ||
1106 | /** | |
1107 | * alloc_highmem_image_pages - allocate some highmem pages for the image. | |
1108 | * Try to allocate as many pages as needed, but if the number of free | |
1109 | * highmem pages is lesser than that, allocate them all. | |
1110 | */ | |
1111 | ||
1112 | static inline unsigned int | |
1113 | alloc_highmem_image_pages(struct memory_bitmap *bm, unsigned int nr_highmem) | |
1114 | { | |
1115 | unsigned int to_alloc = count_free_highmem_pages(); | |
1116 | ||
1117 | if (to_alloc > nr_highmem) | |
1118 | to_alloc = nr_highmem; | |
1119 | ||
1120 | nr_highmem -= to_alloc; | |
1121 | while (to_alloc-- > 0) { | |
1122 | struct page *page; | |
1123 | ||
1124 | page = alloc_image_page(__GFP_HIGHMEM); | |
1125 | memory_bm_set_bit(bm, page_to_pfn(page)); | |
1126 | } | |
1127 | return nr_highmem; | |
1128 | } | |
1129 | #else | |
1130 | static inline int get_highmem_buffer(int safe_needed) { return 0; } | |
1131 | ||
1132 | static inline unsigned int | |
1133 | alloc_highmem_image_pages(struct memory_bitmap *bm, unsigned int n) { return 0; } | |
1134 | #endif /* CONFIG_HIGHMEM */ | |
1135 | ||
1136 | /** | |
1137 | * swsusp_alloc - allocate memory for the suspend image | |
1138 | * | |
1139 | * We first try to allocate as many highmem pages as there are | |
1140 | * saveable highmem pages in the system. If that fails, we allocate | |
1141 | * non-highmem pages for the copies of the remaining highmem ones. | |
1142 | * | |
1143 | * In this approach it is likely that the copies of highmem pages will | |
1144 | * also be located in the high memory, because of the way in which | |
1145 | * copy_data_pages() works. | |
1146 | */ | |
1147 | ||
b788db79 RW |
1148 | static int |
1149 | swsusp_alloc(struct memory_bitmap *orig_bm, struct memory_bitmap *copy_bm, | |
8357376d | 1150 | unsigned int nr_pages, unsigned int nr_highmem) |
054bd4c1 | 1151 | { |
b788db79 | 1152 | int error; |
054bd4c1 | 1153 | |
b788db79 RW |
1154 | error = memory_bm_create(orig_bm, GFP_ATOMIC | __GFP_COLD, PG_ANY); |
1155 | if (error) | |
1156 | goto Free; | |
25761b6e | 1157 | |
b788db79 RW |
1158 | error = memory_bm_create(copy_bm, GFP_ATOMIC | __GFP_COLD, PG_ANY); |
1159 | if (error) | |
1160 | goto Free; | |
25761b6e | 1161 | |
8357376d RW |
1162 | if (nr_highmem > 0) { |
1163 | error = get_highmem_buffer(PG_ANY); | |
1164 | if (error) | |
1165 | goto Free; | |
1166 | ||
1167 | nr_pages += alloc_highmem_image_pages(copy_bm, nr_highmem); | |
1168 | } | |
b788db79 | 1169 | while (nr_pages-- > 0) { |
8357376d RW |
1170 | struct page *page = alloc_image_page(GFP_ATOMIC | __GFP_COLD); |
1171 | ||
b788db79 RW |
1172 | if (!page) |
1173 | goto Free; | |
25761b6e | 1174 | |
b788db79 | 1175 | memory_bm_set_bit(copy_bm, page_to_pfn(page)); |
25761b6e | 1176 | } |
b788db79 | 1177 | return 0; |
25761b6e | 1178 | |
59a49335 | 1179 | Free: |
b788db79 RW |
1180 | swsusp_free(); |
1181 | return -ENOMEM; | |
25761b6e RW |
1182 | } |
1183 | ||
8357376d RW |
1184 | /* Memory bitmap used for marking saveable pages (during suspend) or the |
1185 | * suspend image pages (during resume) | |
1186 | */ | |
b788db79 | 1187 | static struct memory_bitmap orig_bm; |
8357376d RW |
1188 | /* Memory bitmap used on suspend for marking allocated pages that will contain |
1189 | * the copies of saveable pages. During resume it is initially used for | |
1190 | * marking the suspend image pages, but then its set bits are duplicated in | |
1191 | * @orig_bm and it is released. Next, on systems with high memory, it may be | |
1192 | * used for marking "safe" highmem pages, but it has to be reinitialized for | |
1193 | * this purpose. | |
b788db79 RW |
1194 | */ |
1195 | static struct memory_bitmap copy_bm; | |
1196 | ||
2e32a43e | 1197 | asmlinkage int swsusp_save(void) |
25761b6e | 1198 | { |
8357376d | 1199 | unsigned int nr_pages, nr_highmem; |
25761b6e | 1200 | |
23976728 | 1201 | printk(KERN_INFO "PM: Creating hibernation image: \n"); |
25761b6e | 1202 | |
9f8f2172 | 1203 | drain_local_pages(NULL); |
a0f49651 | 1204 | nr_pages = count_data_pages(); |
8357376d | 1205 | nr_highmem = count_highmem_pages(); |
23976728 | 1206 | printk(KERN_INFO "PM: Need to copy %u pages\n", nr_pages + nr_highmem); |
25761b6e | 1207 | |
8357376d | 1208 | if (!enough_free_mem(nr_pages, nr_highmem)) { |
23976728 | 1209 | printk(KERN_ERR "PM: Not enough free memory\n"); |
25761b6e RW |
1210 | return -ENOMEM; |
1211 | } | |
1212 | ||
8357376d | 1213 | if (swsusp_alloc(&orig_bm, ©_bm, nr_pages, nr_highmem)) { |
23976728 | 1214 | printk(KERN_ERR "PM: Memory allocation failed\n"); |
a0f49651 | 1215 | return -ENOMEM; |
8357376d | 1216 | } |
25761b6e RW |
1217 | |
1218 | /* During allocating of suspend pagedir, new cold pages may appear. | |
1219 | * Kill them. | |
1220 | */ | |
9f8f2172 | 1221 | drain_local_pages(NULL); |
b788db79 | 1222 | copy_data_pages(©_bm, &orig_bm); |
25761b6e RW |
1223 | |
1224 | /* | |
1225 | * End of critical section. From now on, we can write to memory, | |
1226 | * but we should not touch disk. This specially means we must _not_ | |
1227 | * touch swap space! Except we must write out our image of course. | |
1228 | */ | |
1229 | ||
8357376d | 1230 | nr_pages += nr_highmem; |
a0f49651 | 1231 | nr_copy_pages = nr_pages; |
8357376d | 1232 | nr_meta_pages = DIV_ROUND_UP(nr_pages * sizeof(long), PAGE_SIZE); |
a0f49651 | 1233 | |
23976728 RW |
1234 | printk(KERN_INFO "PM: Hibernation image created (%d pages copied)\n", |
1235 | nr_pages); | |
8357376d | 1236 | |
25761b6e RW |
1237 | return 0; |
1238 | } | |
f577eb30 | 1239 | |
d307c4a8 RW |
1240 | #ifndef CONFIG_ARCH_HIBERNATION_HEADER |
1241 | static int init_header_complete(struct swsusp_info *info) | |
f577eb30 | 1242 | { |
d307c4a8 | 1243 | memcpy(&info->uts, init_utsname(), sizeof(struct new_utsname)); |
f577eb30 | 1244 | info->version_code = LINUX_VERSION_CODE; |
d307c4a8 RW |
1245 | return 0; |
1246 | } | |
1247 | ||
1248 | static char *check_image_kernel(struct swsusp_info *info) | |
1249 | { | |
1250 | if (info->version_code != LINUX_VERSION_CODE) | |
1251 | return "kernel version"; | |
1252 | if (strcmp(info->uts.sysname,init_utsname()->sysname)) | |
1253 | return "system type"; | |
1254 | if (strcmp(info->uts.release,init_utsname()->release)) | |
1255 | return "kernel release"; | |
1256 | if (strcmp(info->uts.version,init_utsname()->version)) | |
1257 | return "version"; | |
1258 | if (strcmp(info->uts.machine,init_utsname()->machine)) | |
1259 | return "machine"; | |
1260 | return NULL; | |
1261 | } | |
1262 | #endif /* CONFIG_ARCH_HIBERNATION_HEADER */ | |
1263 | ||
af508b34 RW |
1264 | unsigned long snapshot_get_image_size(void) |
1265 | { | |
1266 | return nr_copy_pages + nr_meta_pages + 1; | |
1267 | } | |
1268 | ||
d307c4a8 RW |
1269 | static int init_header(struct swsusp_info *info) |
1270 | { | |
1271 | memset(info, 0, sizeof(struct swsusp_info)); | |
f577eb30 | 1272 | info->num_physpages = num_physpages; |
f577eb30 | 1273 | info->image_pages = nr_copy_pages; |
af508b34 | 1274 | info->pages = snapshot_get_image_size(); |
6e1819d6 RW |
1275 | info->size = info->pages; |
1276 | info->size <<= PAGE_SHIFT; | |
d307c4a8 | 1277 | return init_header_complete(info); |
f577eb30 RW |
1278 | } |
1279 | ||
1280 | /** | |
940864dd RW |
1281 | * pack_pfns - pfns corresponding to the set bits found in the bitmap @bm |
1282 | * are stored in the array @buf[] (1 page at a time) | |
f577eb30 RW |
1283 | */ |
1284 | ||
b788db79 | 1285 | static inline void |
940864dd | 1286 | pack_pfns(unsigned long *buf, struct memory_bitmap *bm) |
f577eb30 RW |
1287 | { |
1288 | int j; | |
1289 | ||
b788db79 | 1290 | for (j = 0; j < PAGE_SIZE / sizeof(long); j++) { |
940864dd RW |
1291 | buf[j] = memory_bm_next_pfn(bm); |
1292 | if (unlikely(buf[j] == BM_END_OF_MAP)) | |
b788db79 | 1293 | break; |
f577eb30 | 1294 | } |
f577eb30 RW |
1295 | } |
1296 | ||
1297 | /** | |
1298 | * snapshot_read_next - used for reading the system memory snapshot. | |
1299 | * | |
1300 | * On the first call to it @handle should point to a zeroed | |
1301 | * snapshot_handle structure. The structure gets updated and a pointer | |
1302 | * to it should be passed to this function every next time. | |
1303 | * | |
1304 | * The @count parameter should contain the number of bytes the caller | |
1305 | * wants to read from the snapshot. It must not be zero. | |
1306 | * | |
1307 | * On success the function returns a positive number. Then, the caller | |
1308 | * is allowed to read up to the returned number of bytes from the memory | |
1309 | * location computed by the data_of() macro. The number returned | |
1310 | * may be smaller than @count, but this only happens if the read would | |
1311 | * cross a page boundary otherwise. | |
1312 | * | |
1313 | * The function returns 0 to indicate the end of data stream condition, | |
1314 | * and a negative number is returned on error. In such cases the | |
1315 | * structure pointed to by @handle is not updated and should not be used | |
1316 | * any more. | |
1317 | */ | |
1318 | ||
1319 | int snapshot_read_next(struct snapshot_handle *handle, size_t count) | |
1320 | { | |
fb13a28b | 1321 | if (handle->cur > nr_meta_pages + nr_copy_pages) |
f577eb30 | 1322 | return 0; |
b788db79 | 1323 | |
f577eb30 RW |
1324 | if (!buffer) { |
1325 | /* This makes the buffer be freed by swsusp_free() */ | |
8357376d | 1326 | buffer = get_image_page(GFP_ATOMIC, PG_ANY); |
f577eb30 RW |
1327 | if (!buffer) |
1328 | return -ENOMEM; | |
1329 | } | |
1330 | if (!handle->offset) { | |
d307c4a8 RW |
1331 | int error; |
1332 | ||
1333 | error = init_header((struct swsusp_info *)buffer); | |
1334 | if (error) | |
1335 | return error; | |
f577eb30 | 1336 | handle->buffer = buffer; |
b788db79 RW |
1337 | memory_bm_position_reset(&orig_bm); |
1338 | memory_bm_position_reset(©_bm); | |
f577eb30 | 1339 | } |
fb13a28b RW |
1340 | if (handle->prev < handle->cur) { |
1341 | if (handle->cur <= nr_meta_pages) { | |
b788db79 | 1342 | memset(buffer, 0, PAGE_SIZE); |
940864dd | 1343 | pack_pfns(buffer, &orig_bm); |
f577eb30 | 1344 | } else { |
8357376d | 1345 | struct page *page; |
b788db79 | 1346 | |
8357376d RW |
1347 | page = pfn_to_page(memory_bm_next_pfn(©_bm)); |
1348 | if (PageHighMem(page)) { | |
1349 | /* Highmem pages are copied to the buffer, | |
1350 | * because we can't return with a kmapped | |
1351 | * highmem page (we may not be called again). | |
1352 | */ | |
1353 | void *kaddr; | |
1354 | ||
1355 | kaddr = kmap_atomic(page, KM_USER0); | |
1356 | memcpy(buffer, kaddr, PAGE_SIZE); | |
1357 | kunmap_atomic(kaddr, KM_USER0); | |
1358 | handle->buffer = buffer; | |
1359 | } else { | |
1360 | handle->buffer = page_address(page); | |
1361 | } | |
f577eb30 | 1362 | } |
fb13a28b | 1363 | handle->prev = handle->cur; |
f577eb30 | 1364 | } |
fb13a28b RW |
1365 | handle->buf_offset = handle->cur_offset; |
1366 | if (handle->cur_offset + count >= PAGE_SIZE) { | |
1367 | count = PAGE_SIZE - handle->cur_offset; | |
1368 | handle->cur_offset = 0; | |
1369 | handle->cur++; | |
f577eb30 | 1370 | } else { |
fb13a28b | 1371 | handle->cur_offset += count; |
f577eb30 RW |
1372 | } |
1373 | handle->offset += count; | |
1374 | return count; | |
1375 | } | |
1376 | ||
1377 | /** | |
1378 | * mark_unsafe_pages - mark the pages that cannot be used for storing | |
1379 | * the image during resume, because they conflict with the pages that | |
1380 | * had been used before suspend | |
1381 | */ | |
1382 | ||
940864dd | 1383 | static int mark_unsafe_pages(struct memory_bitmap *bm) |
f577eb30 RW |
1384 | { |
1385 | struct zone *zone; | |
ae83c5ee | 1386 | unsigned long pfn, max_zone_pfn; |
f577eb30 RW |
1387 | |
1388 | /* Clear page flags */ | |
8357376d | 1389 | for_each_zone(zone) { |
ae83c5ee RW |
1390 | max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; |
1391 | for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) | |
1392 | if (pfn_valid(pfn)) | |
7be98234 | 1393 | swsusp_unset_page_free(pfn_to_page(pfn)); |
f577eb30 RW |
1394 | } |
1395 | ||
940864dd RW |
1396 | /* Mark pages that correspond to the "original" pfns as "unsafe" */ |
1397 | memory_bm_position_reset(bm); | |
1398 | do { | |
1399 | pfn = memory_bm_next_pfn(bm); | |
1400 | if (likely(pfn != BM_END_OF_MAP)) { | |
1401 | if (likely(pfn_valid(pfn))) | |
7be98234 | 1402 | swsusp_set_page_free(pfn_to_page(pfn)); |
940864dd RW |
1403 | else |
1404 | return -EFAULT; | |
1405 | } | |
1406 | } while (pfn != BM_END_OF_MAP); | |
f577eb30 | 1407 | |
940864dd | 1408 | allocated_unsafe_pages = 0; |
968808b8 | 1409 | |
f577eb30 RW |
1410 | return 0; |
1411 | } | |
1412 | ||
940864dd RW |
1413 | static void |
1414 | duplicate_memory_bitmap(struct memory_bitmap *dst, struct memory_bitmap *src) | |
f577eb30 | 1415 | { |
940864dd RW |
1416 | unsigned long pfn; |
1417 | ||
1418 | memory_bm_position_reset(src); | |
1419 | pfn = memory_bm_next_pfn(src); | |
1420 | while (pfn != BM_END_OF_MAP) { | |
1421 | memory_bm_set_bit(dst, pfn); | |
1422 | pfn = memory_bm_next_pfn(src); | |
f577eb30 RW |
1423 | } |
1424 | } | |
1425 | ||
d307c4a8 | 1426 | static int check_header(struct swsusp_info *info) |
f577eb30 | 1427 | { |
d307c4a8 | 1428 | char *reason; |
f577eb30 | 1429 | |
d307c4a8 RW |
1430 | reason = check_image_kernel(info); |
1431 | if (!reason && info->num_physpages != num_physpages) | |
f577eb30 | 1432 | reason = "memory size"; |
f577eb30 | 1433 | if (reason) { |
23976728 | 1434 | printk(KERN_ERR "PM: Image mismatch: %s\n", reason); |
f577eb30 RW |
1435 | return -EPERM; |
1436 | } | |
1437 | return 0; | |
1438 | } | |
1439 | ||
1440 | /** | |
1441 | * load header - check the image header and copy data from it | |
1442 | */ | |
1443 | ||
940864dd RW |
1444 | static int |
1445 | load_header(struct swsusp_info *info) | |
f577eb30 RW |
1446 | { |
1447 | int error; | |
f577eb30 | 1448 | |
940864dd | 1449 | restore_pblist = NULL; |
f577eb30 RW |
1450 | error = check_header(info); |
1451 | if (!error) { | |
f577eb30 RW |
1452 | nr_copy_pages = info->image_pages; |
1453 | nr_meta_pages = info->pages - info->image_pages - 1; | |
1454 | } | |
1455 | return error; | |
1456 | } | |
1457 | ||
1458 | /** | |
940864dd RW |
1459 | * unpack_orig_pfns - for each element of @buf[] (1 page at a time) set |
1460 | * the corresponding bit in the memory bitmap @bm | |
f577eb30 RW |
1461 | */ |
1462 | ||
940864dd RW |
1463 | static inline void |
1464 | unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm) | |
f577eb30 RW |
1465 | { |
1466 | int j; | |
1467 | ||
940864dd RW |
1468 | for (j = 0; j < PAGE_SIZE / sizeof(long); j++) { |
1469 | if (unlikely(buf[j] == BM_END_OF_MAP)) | |
1470 | break; | |
1471 | ||
1472 | memory_bm_set_bit(bm, buf[j]); | |
f577eb30 | 1473 | } |
f577eb30 RW |
1474 | } |
1475 | ||
8357376d RW |
1476 | /* List of "safe" pages that may be used to store data loaded from the suspend |
1477 | * image | |
1478 | */ | |
1479 | static struct linked_page *safe_pages_list; | |
1480 | ||
1481 | #ifdef CONFIG_HIGHMEM | |
1482 | /* struct highmem_pbe is used for creating the list of highmem pages that | |
1483 | * should be restored atomically during the resume from disk, because the page | |
1484 | * frames they have occupied before the suspend are in use. | |
1485 | */ | |
1486 | struct highmem_pbe { | |
1487 | struct page *copy_page; /* data is here now */ | |
1488 | struct page *orig_page; /* data was here before the suspend */ | |
1489 | struct highmem_pbe *next; | |
1490 | }; | |
1491 | ||
1492 | /* List of highmem PBEs needed for restoring the highmem pages that were | |
1493 | * allocated before the suspend and included in the suspend image, but have | |
1494 | * also been allocated by the "resume" kernel, so their contents cannot be | |
1495 | * written directly to their "original" page frames. | |
1496 | */ | |
1497 | static struct highmem_pbe *highmem_pblist; | |
1498 | ||
1499 | /** | |
1500 | * count_highmem_image_pages - compute the number of highmem pages in the | |
1501 | * suspend image. The bits in the memory bitmap @bm that correspond to the | |
1502 | * image pages are assumed to be set. | |
1503 | */ | |
1504 | ||
1505 | static unsigned int count_highmem_image_pages(struct memory_bitmap *bm) | |
1506 | { | |
1507 | unsigned long pfn; | |
1508 | unsigned int cnt = 0; | |
1509 | ||
1510 | memory_bm_position_reset(bm); | |
1511 | pfn = memory_bm_next_pfn(bm); | |
1512 | while (pfn != BM_END_OF_MAP) { | |
1513 | if (PageHighMem(pfn_to_page(pfn))) | |
1514 | cnt++; | |
1515 | ||
1516 | pfn = memory_bm_next_pfn(bm); | |
1517 | } | |
1518 | return cnt; | |
1519 | } | |
1520 | ||
1521 | /** | |
1522 | * prepare_highmem_image - try to allocate as many highmem pages as | |
1523 | * there are highmem image pages (@nr_highmem_p points to the variable | |
1524 | * containing the number of highmem image pages). The pages that are | |
1525 | * "safe" (ie. will not be overwritten when the suspend image is | |
1526 | * restored) have the corresponding bits set in @bm (it must be | |
1527 | * unitialized). | |
1528 | * | |
1529 | * NOTE: This function should not be called if there are no highmem | |
1530 | * image pages. | |
1531 | */ | |
1532 | ||
1533 | static unsigned int safe_highmem_pages; | |
1534 | ||
1535 | static struct memory_bitmap *safe_highmem_bm; | |
1536 | ||
1537 | static int | |
1538 | prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p) | |
1539 | { | |
1540 | unsigned int to_alloc; | |
1541 | ||
1542 | if (memory_bm_create(bm, GFP_ATOMIC, PG_SAFE)) | |
1543 | return -ENOMEM; | |
1544 | ||
1545 | if (get_highmem_buffer(PG_SAFE)) | |
1546 | return -ENOMEM; | |
1547 | ||
1548 | to_alloc = count_free_highmem_pages(); | |
1549 | if (to_alloc > *nr_highmem_p) | |
1550 | to_alloc = *nr_highmem_p; | |
1551 | else | |
1552 | *nr_highmem_p = to_alloc; | |
1553 | ||
1554 | safe_highmem_pages = 0; | |
1555 | while (to_alloc-- > 0) { | |
1556 | struct page *page; | |
1557 | ||
1558 | page = alloc_page(__GFP_HIGHMEM); | |
7be98234 | 1559 | if (!swsusp_page_is_free(page)) { |
8357376d RW |
1560 | /* The page is "safe", set its bit the bitmap */ |
1561 | memory_bm_set_bit(bm, page_to_pfn(page)); | |
1562 | safe_highmem_pages++; | |
1563 | } | |
1564 | /* Mark the page as allocated */ | |
7be98234 RW |
1565 | swsusp_set_page_forbidden(page); |
1566 | swsusp_set_page_free(page); | |
8357376d RW |
1567 | } |
1568 | memory_bm_position_reset(bm); | |
1569 | safe_highmem_bm = bm; | |
1570 | return 0; | |
1571 | } | |
1572 | ||
1573 | /** | |
1574 | * get_highmem_page_buffer - for given highmem image page find the buffer | |
1575 | * that suspend_write_next() should set for its caller to write to. | |
1576 | * | |
1577 | * If the page is to be saved to its "original" page frame or a copy of | |
1578 | * the page is to be made in the highmem, @buffer is returned. Otherwise, | |
1579 | * the copy of the page is to be made in normal memory, so the address of | |
1580 | * the copy is returned. | |
1581 | * | |
1582 | * If @buffer is returned, the caller of suspend_write_next() will write | |
1583 | * the page's contents to @buffer, so they will have to be copied to the | |
1584 | * right location on the next call to suspend_write_next() and it is done | |
1585 | * with the help of copy_last_highmem_page(). For this purpose, if | |
1586 | * @buffer is returned, @last_highmem page is set to the page to which | |
1587 | * the data will have to be copied from @buffer. | |
1588 | */ | |
1589 | ||
1590 | static struct page *last_highmem_page; | |
1591 | ||
1592 | static void * | |
1593 | get_highmem_page_buffer(struct page *page, struct chain_allocator *ca) | |
1594 | { | |
1595 | struct highmem_pbe *pbe; | |
1596 | void *kaddr; | |
1597 | ||
7be98234 | 1598 | if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page)) { |
8357376d RW |
1599 | /* We have allocated the "original" page frame and we can |
1600 | * use it directly to store the loaded page. | |
1601 | */ | |
1602 | last_highmem_page = page; | |
1603 | return buffer; | |
1604 | } | |
1605 | /* The "original" page frame has not been allocated and we have to | |
1606 | * use a "safe" page frame to store the loaded page. | |
1607 | */ | |
1608 | pbe = chain_alloc(ca, sizeof(struct highmem_pbe)); | |
1609 | if (!pbe) { | |
1610 | swsusp_free(); | |
1611 | return NULL; | |
1612 | } | |
1613 | pbe->orig_page = page; | |
1614 | if (safe_highmem_pages > 0) { | |
1615 | struct page *tmp; | |
1616 | ||
1617 | /* Copy of the page will be stored in high memory */ | |
1618 | kaddr = buffer; | |
1619 | tmp = pfn_to_page(memory_bm_next_pfn(safe_highmem_bm)); | |
1620 | safe_highmem_pages--; | |
1621 | last_highmem_page = tmp; | |
1622 | pbe->copy_page = tmp; | |
1623 | } else { | |
1624 | /* Copy of the page will be stored in normal memory */ | |
1625 | kaddr = safe_pages_list; | |
1626 | safe_pages_list = safe_pages_list->next; | |
1627 | pbe->copy_page = virt_to_page(kaddr); | |
1628 | } | |
1629 | pbe->next = highmem_pblist; | |
1630 | highmem_pblist = pbe; | |
1631 | return kaddr; | |
1632 | } | |
1633 | ||
1634 | /** | |
1635 | * copy_last_highmem_page - copy the contents of a highmem image from | |
1636 | * @buffer, where the caller of snapshot_write_next() has place them, | |
1637 | * to the right location represented by @last_highmem_page . | |
1638 | */ | |
1639 | ||
1640 | static void copy_last_highmem_page(void) | |
1641 | { | |
1642 | if (last_highmem_page) { | |
1643 | void *dst; | |
1644 | ||
1645 | dst = kmap_atomic(last_highmem_page, KM_USER0); | |
1646 | memcpy(dst, buffer, PAGE_SIZE); | |
1647 | kunmap_atomic(dst, KM_USER0); | |
1648 | last_highmem_page = NULL; | |
1649 | } | |
1650 | } | |
1651 | ||
1652 | static inline int last_highmem_page_copied(void) | |
1653 | { | |
1654 | return !last_highmem_page; | |
1655 | } | |
1656 | ||
1657 | static inline void free_highmem_data(void) | |
1658 | { | |
1659 | if (safe_highmem_bm) | |
1660 | memory_bm_free(safe_highmem_bm, PG_UNSAFE_CLEAR); | |
1661 | ||
1662 | if (buffer) | |
1663 | free_image_page(buffer, PG_UNSAFE_CLEAR); | |
1664 | } | |
1665 | #else | |
1666 | static inline int get_safe_write_buffer(void) { return 0; } | |
1667 | ||
1668 | static unsigned int | |
1669 | count_highmem_image_pages(struct memory_bitmap *bm) { return 0; } | |
1670 | ||
1671 | static inline int | |
1672 | prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p) | |
1673 | { | |
1674 | return 0; | |
1675 | } | |
1676 | ||
1677 | static inline void * | |
1678 | get_highmem_page_buffer(struct page *page, struct chain_allocator *ca) | |
1679 | { | |
1680 | return NULL; | |
1681 | } | |
1682 | ||
1683 | static inline void copy_last_highmem_page(void) {} | |
1684 | static inline int last_highmem_page_copied(void) { return 1; } | |
1685 | static inline void free_highmem_data(void) {} | |
1686 | #endif /* CONFIG_HIGHMEM */ | |
1687 | ||
f577eb30 | 1688 | /** |
940864dd RW |
1689 | * prepare_image - use the memory bitmap @bm to mark the pages that will |
1690 | * be overwritten in the process of restoring the system memory state | |
1691 | * from the suspend image ("unsafe" pages) and allocate memory for the | |
1692 | * image. | |
968808b8 | 1693 | * |
940864dd RW |
1694 | * The idea is to allocate a new memory bitmap first and then allocate |
1695 | * as many pages as needed for the image data, but not to assign these | |
1696 | * pages to specific tasks initially. Instead, we just mark them as | |
8357376d RW |
1697 | * allocated and create a lists of "safe" pages that will be used |
1698 | * later. On systems with high memory a list of "safe" highmem pages is | |
1699 | * also created. | |
f577eb30 RW |
1700 | */ |
1701 | ||
940864dd RW |
1702 | #define PBES_PER_LINKED_PAGE (LINKED_PAGE_DATA_SIZE / sizeof(struct pbe)) |
1703 | ||
940864dd RW |
1704 | static int |
1705 | prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm) | |
f577eb30 | 1706 | { |
8357376d | 1707 | unsigned int nr_pages, nr_highmem; |
940864dd RW |
1708 | struct linked_page *sp_list, *lp; |
1709 | int error; | |
f577eb30 | 1710 | |
8357376d RW |
1711 | /* If there is no highmem, the buffer will not be necessary */ |
1712 | free_image_page(buffer, PG_UNSAFE_CLEAR); | |
1713 | buffer = NULL; | |
1714 | ||
1715 | nr_highmem = count_highmem_image_pages(bm); | |
940864dd RW |
1716 | error = mark_unsafe_pages(bm); |
1717 | if (error) | |
1718 | goto Free; | |
1719 | ||
1720 | error = memory_bm_create(new_bm, GFP_ATOMIC, PG_SAFE); | |
1721 | if (error) | |
1722 | goto Free; | |
1723 | ||
1724 | duplicate_memory_bitmap(new_bm, bm); | |
1725 | memory_bm_free(bm, PG_UNSAFE_KEEP); | |
8357376d RW |
1726 | if (nr_highmem > 0) { |
1727 | error = prepare_highmem_image(bm, &nr_highmem); | |
1728 | if (error) | |
1729 | goto Free; | |
1730 | } | |
940864dd RW |
1731 | /* Reserve some safe pages for potential later use. |
1732 | * | |
1733 | * NOTE: This way we make sure there will be enough safe pages for the | |
1734 | * chain_alloc() in get_buffer(). It is a bit wasteful, but | |
1735 | * nr_copy_pages cannot be greater than 50% of the memory anyway. | |
1736 | */ | |
1737 | sp_list = NULL; | |
1738 | /* nr_copy_pages cannot be lesser than allocated_unsafe_pages */ | |
8357376d | 1739 | nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages; |
940864dd RW |
1740 | nr_pages = DIV_ROUND_UP(nr_pages, PBES_PER_LINKED_PAGE); |
1741 | while (nr_pages > 0) { | |
8357376d | 1742 | lp = get_image_page(GFP_ATOMIC, PG_SAFE); |
940864dd | 1743 | if (!lp) { |
f577eb30 | 1744 | error = -ENOMEM; |
940864dd RW |
1745 | goto Free; |
1746 | } | |
1747 | lp->next = sp_list; | |
1748 | sp_list = lp; | |
1749 | nr_pages--; | |
f577eb30 | 1750 | } |
940864dd RW |
1751 | /* Preallocate memory for the image */ |
1752 | safe_pages_list = NULL; | |
8357376d | 1753 | nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages; |
940864dd RW |
1754 | while (nr_pages > 0) { |
1755 | lp = (struct linked_page *)get_zeroed_page(GFP_ATOMIC); | |
1756 | if (!lp) { | |
1757 | error = -ENOMEM; | |
1758 | goto Free; | |
1759 | } | |
7be98234 | 1760 | if (!swsusp_page_is_free(virt_to_page(lp))) { |
940864dd RW |
1761 | /* The page is "safe", add it to the list */ |
1762 | lp->next = safe_pages_list; | |
1763 | safe_pages_list = lp; | |
968808b8 | 1764 | } |
940864dd | 1765 | /* Mark the page as allocated */ |
7be98234 RW |
1766 | swsusp_set_page_forbidden(virt_to_page(lp)); |
1767 | swsusp_set_page_free(virt_to_page(lp)); | |
940864dd | 1768 | nr_pages--; |
968808b8 | 1769 | } |
940864dd RW |
1770 | /* Free the reserved safe pages so that chain_alloc() can use them */ |
1771 | while (sp_list) { | |
1772 | lp = sp_list->next; | |
1773 | free_image_page(sp_list, PG_UNSAFE_CLEAR); | |
1774 | sp_list = lp; | |
f577eb30 | 1775 | } |
940864dd RW |
1776 | return 0; |
1777 | ||
59a49335 | 1778 | Free: |
940864dd | 1779 | swsusp_free(); |
f577eb30 RW |
1780 | return error; |
1781 | } | |
1782 | ||
940864dd RW |
1783 | /** |
1784 | * get_buffer - compute the address that snapshot_write_next() should | |
1785 | * set for its caller to write to. | |
1786 | */ | |
1787 | ||
1788 | static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca) | |
968808b8 | 1789 | { |
940864dd RW |
1790 | struct pbe *pbe; |
1791 | struct page *page = pfn_to_page(memory_bm_next_pfn(bm)); | |
968808b8 | 1792 | |
8357376d RW |
1793 | if (PageHighMem(page)) |
1794 | return get_highmem_page_buffer(page, ca); | |
1795 | ||
7be98234 | 1796 | if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page)) |
940864dd RW |
1797 | /* We have allocated the "original" page frame and we can |
1798 | * use it directly to store the loaded page. | |
968808b8 | 1799 | */ |
940864dd RW |
1800 | return page_address(page); |
1801 | ||
1802 | /* The "original" page frame has not been allocated and we have to | |
1803 | * use a "safe" page frame to store the loaded page. | |
968808b8 | 1804 | */ |
940864dd RW |
1805 | pbe = chain_alloc(ca, sizeof(struct pbe)); |
1806 | if (!pbe) { | |
1807 | swsusp_free(); | |
1808 | return NULL; | |
1809 | } | |
8357376d RW |
1810 | pbe->orig_address = page_address(page); |
1811 | pbe->address = safe_pages_list; | |
940864dd RW |
1812 | safe_pages_list = safe_pages_list->next; |
1813 | pbe->next = restore_pblist; | |
1814 | restore_pblist = pbe; | |
8357376d | 1815 | return pbe->address; |
968808b8 RW |
1816 | } |
1817 | ||
f577eb30 RW |
1818 | /** |
1819 | * snapshot_write_next - used for writing the system memory snapshot. | |
1820 | * | |
1821 | * On the first call to it @handle should point to a zeroed | |
1822 | * snapshot_handle structure. The structure gets updated and a pointer | |
1823 | * to it should be passed to this function every next time. | |
1824 | * | |
1825 | * The @count parameter should contain the number of bytes the caller | |
1826 | * wants to write to the image. It must not be zero. | |
1827 | * | |
1828 | * On success the function returns a positive number. Then, the caller | |
1829 | * is allowed to write up to the returned number of bytes to the memory | |
1830 | * location computed by the data_of() macro. The number returned | |
1831 | * may be smaller than @count, but this only happens if the write would | |
1832 | * cross a page boundary otherwise. | |
1833 | * | |
1834 | * The function returns 0 to indicate the "end of file" condition, | |
1835 | * and a negative number is returned on error. In such cases the | |
1836 | * structure pointed to by @handle is not updated and should not be used | |
1837 | * any more. | |
1838 | */ | |
1839 | ||
1840 | int snapshot_write_next(struct snapshot_handle *handle, size_t count) | |
1841 | { | |
940864dd | 1842 | static struct chain_allocator ca; |
f577eb30 RW |
1843 | int error = 0; |
1844 | ||
940864dd | 1845 | /* Check if we have already loaded the entire image */ |
fb13a28b | 1846 | if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages) |
f577eb30 | 1847 | return 0; |
940864dd | 1848 | |
8357376d RW |
1849 | if (handle->offset == 0) { |
1850 | if (!buffer) | |
1851 | /* This makes the buffer be freed by swsusp_free() */ | |
1852 | buffer = get_image_page(GFP_ATOMIC, PG_ANY); | |
1853 | ||
f577eb30 RW |
1854 | if (!buffer) |
1855 | return -ENOMEM; | |
8357376d | 1856 | |
f577eb30 | 1857 | handle->buffer = buffer; |
8357376d | 1858 | } |
546e0d27 | 1859 | handle->sync_read = 1; |
fb13a28b | 1860 | if (handle->prev < handle->cur) { |
940864dd RW |
1861 | if (handle->prev == 0) { |
1862 | error = load_header(buffer); | |
1863 | if (error) | |
1864 | return error; | |
1865 | ||
1866 | error = memory_bm_create(©_bm, GFP_ATOMIC, PG_ANY); | |
f577eb30 RW |
1867 | if (error) |
1868 | return error; | |
940864dd | 1869 | |
f577eb30 | 1870 | } else if (handle->prev <= nr_meta_pages) { |
940864dd RW |
1871 | unpack_orig_pfns(buffer, ©_bm); |
1872 | if (handle->prev == nr_meta_pages) { | |
1873 | error = prepare_image(&orig_bm, ©_bm); | |
f577eb30 RW |
1874 | if (error) |
1875 | return error; | |
940864dd RW |
1876 | |
1877 | chain_init(&ca, GFP_ATOMIC, PG_SAFE); | |
1878 | memory_bm_position_reset(&orig_bm); | |
1879 | restore_pblist = NULL; | |
1880 | handle->buffer = get_buffer(&orig_bm, &ca); | |
546e0d27 | 1881 | handle->sync_read = 0; |
940864dd RW |
1882 | if (!handle->buffer) |
1883 | return -ENOMEM; | |
f577eb30 RW |
1884 | } |
1885 | } else { | |
8357376d | 1886 | copy_last_highmem_page(); |
940864dd | 1887 | handle->buffer = get_buffer(&orig_bm, &ca); |
8357376d RW |
1888 | if (handle->buffer != buffer) |
1889 | handle->sync_read = 0; | |
f577eb30 | 1890 | } |
fb13a28b | 1891 | handle->prev = handle->cur; |
f577eb30 | 1892 | } |
fb13a28b RW |
1893 | handle->buf_offset = handle->cur_offset; |
1894 | if (handle->cur_offset + count >= PAGE_SIZE) { | |
1895 | count = PAGE_SIZE - handle->cur_offset; | |
1896 | handle->cur_offset = 0; | |
1897 | handle->cur++; | |
f577eb30 | 1898 | } else { |
fb13a28b | 1899 | handle->cur_offset += count; |
f577eb30 RW |
1900 | } |
1901 | handle->offset += count; | |
1902 | return count; | |
1903 | } | |
1904 | ||
8357376d RW |
1905 | /** |
1906 | * snapshot_write_finalize - must be called after the last call to | |
1907 | * snapshot_write_next() in case the last page in the image happens | |
1908 | * to be a highmem page and its contents should be stored in the | |
1909 | * highmem. Additionally, it releases the memory that will not be | |
1910 | * used any more. | |
1911 | */ | |
1912 | ||
1913 | void snapshot_write_finalize(struct snapshot_handle *handle) | |
1914 | { | |
1915 | copy_last_highmem_page(); | |
1916 | /* Free only if we have loaded the image entirely */ | |
1917 | if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages) { | |
1918 | memory_bm_free(&orig_bm, PG_UNSAFE_CLEAR); | |
1919 | free_highmem_data(); | |
1920 | } | |
1921 | } | |
1922 | ||
f577eb30 RW |
1923 | int snapshot_image_loaded(struct snapshot_handle *handle) |
1924 | { | |
8357376d | 1925 | return !(!nr_copy_pages || !last_highmem_page_copied() || |
940864dd RW |
1926 | handle->cur <= nr_meta_pages + nr_copy_pages); |
1927 | } | |
1928 | ||
8357376d RW |
1929 | #ifdef CONFIG_HIGHMEM |
1930 | /* Assumes that @buf is ready and points to a "safe" page */ | |
1931 | static inline void | |
1932 | swap_two_pages_data(struct page *p1, struct page *p2, void *buf) | |
940864dd | 1933 | { |
8357376d RW |
1934 | void *kaddr1, *kaddr2; |
1935 | ||
1936 | kaddr1 = kmap_atomic(p1, KM_USER0); | |
1937 | kaddr2 = kmap_atomic(p2, KM_USER1); | |
1938 | memcpy(buf, kaddr1, PAGE_SIZE); | |
1939 | memcpy(kaddr1, kaddr2, PAGE_SIZE); | |
1940 | memcpy(kaddr2, buf, PAGE_SIZE); | |
1941 | kunmap_atomic(kaddr1, KM_USER0); | |
1942 | kunmap_atomic(kaddr2, KM_USER1); | |
1943 | } | |
1944 | ||
1945 | /** | |
1946 | * restore_highmem - for each highmem page that was allocated before | |
1947 | * the suspend and included in the suspend image, and also has been | |
1948 | * allocated by the "resume" kernel swap its current (ie. "before | |
1949 | * resume") contents with the previous (ie. "before suspend") one. | |
1950 | * | |
1951 | * If the resume eventually fails, we can call this function once | |
1952 | * again and restore the "before resume" highmem state. | |
1953 | */ | |
1954 | ||
1955 | int restore_highmem(void) | |
1956 | { | |
1957 | struct highmem_pbe *pbe = highmem_pblist; | |
1958 | void *buf; | |
1959 | ||
1960 | if (!pbe) | |
1961 | return 0; | |
1962 | ||
1963 | buf = get_image_page(GFP_ATOMIC, PG_SAFE); | |
1964 | if (!buf) | |
1965 | return -ENOMEM; | |
1966 | ||
1967 | while (pbe) { | |
1968 | swap_two_pages_data(pbe->copy_page, pbe->orig_page, buf); | |
1969 | pbe = pbe->next; | |
1970 | } | |
1971 | free_image_page(buf, PG_UNSAFE_CLEAR); | |
1972 | return 0; | |
f577eb30 | 1973 | } |
8357376d | 1974 | #endif /* CONFIG_HIGHMEM */ |