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Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001/*
Pavel Machek96bc7ae2005-10-30 14:59:58 -08002 * linux/kernel/power/snapshot.c
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08003 *
Rafael J. Wysocki83573762006-12-06 20:34:18 -08004 * This file provides system snapshot/restore functionality for swsusp.
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08005 *
6 * Copyright (C) 1998-2005 Pavel Machek <pavel@suse.cz>
Rafael J. Wysocki83573762006-12-06 20:34:18 -08007 * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl>
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08008 *
Rafael J. Wysocki83573762006-12-06 20:34:18 -08009 * This file is released under the GPLv2.
Rafael J. Wysocki25761b62005-10-30 14:59:56 -080010 *
11 */
12
Rafael J. Wysockif577eb32006-03-23 02:59:59 -080013#include <linux/version.h>
Rafael J. Wysocki25761b62005-10-30 14:59:56 -080014#include <linux/module.h>
15#include <linux/mm.h>
16#include <linux/suspend.h>
Rafael J. Wysocki25761b62005-10-30 14:59:56 -080017#include <linux/delay.h>
Rafael J. Wysocki25761b62005-10-30 14:59:56 -080018#include <linux/bitops.h>
Rafael J. Wysocki25761b62005-10-30 14:59:56 -080019#include <linux/spinlock.h>
Rafael J. Wysocki25761b62005-10-30 14:59:56 -080020#include <linux/kernel.h>
Rafael J. Wysocki25761b62005-10-30 14:59:56 -080021#include <linux/pm.h>
22#include <linux/device.h>
Rafael J. Wysocki74dfd662007-05-06 14:50:43 -070023#include <linux/init.h>
Rafael J. Wysocki25761b62005-10-30 14:59:56 -080024#include <linux/bootmem.h>
25#include <linux/syscalls.h>
26#include <linux/console.h>
27#include <linux/highmem.h>
Rafael J. Wysocki25761b62005-10-30 14:59:56 -080028
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
Rafael J. Wysocki25761b62005-10-30 14:59:56 -080035#include "power.h"
36
Rafael J. Wysocki74dfd662007-05-06 14:50:43 -070037static int swsusp_page_is_free(struct page *);
38static void swsusp_set_page_forbidden(struct page *);
39static void swsusp_unset_page_forbidden(struct page *);
40
Rafael J. Wysocki83573762006-12-06 20:34:18 -080041/* 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 */
Rafael J. Wysocki75534b52006-09-25 23:32:52 -070046struct pbe *restore_pblist;
47
Rafael J. Wysocki83573762006-12-06 20:34:18 -080048/* Pointer to an auxiliary buffer (1 page) */
Rafael J. Wysocki940864d2006-09-25 23:32:55 -070049static void *buffer;
Rafael J. Wysocki7088a5c2006-01-06 00:13:05 -080050
Rafael J. Wysockif6143aa2006-09-25 23:32:50 -070051/**
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
Rafael J. Wysocki83573762006-12-06 20:34:18 -080054 * used before suspend. The unsafe pages have PageNosaveFree set
55 * and we count them using unsafe_pages.
Rafael J. Wysockif6143aa2006-09-25 23:32:50 -070056 *
Rafael J. Wysocki83573762006-12-06 20:34:18 -080057 * Each allocated image page is marked as PageNosave and PageNosaveFree
58 * so that swsusp_free() can release it.
Rafael J. Wysockif6143aa2006-09-25 23:32:50 -070059 */
60
Rafael J. Wysocki0bcd8882006-09-25 23:32:52 -070061#define PG_ANY 0
62#define PG_SAFE 1
63#define PG_UNSAFE_CLEAR 1
64#define PG_UNSAFE_KEEP 0
65
Rafael J. Wysocki940864d2006-09-25 23:32:55 -070066static unsigned int allocated_unsafe_pages;
Rafael J. Wysockif6143aa2006-09-25 23:32:50 -070067
Rafael J. Wysocki83573762006-12-06 20:34:18 -080068static void *get_image_page(gfp_t gfp_mask, int safe_needed)
Rafael J. Wysockif6143aa2006-09-25 23:32:50 -070069{
70 void *res;
71
72 res = (void *)get_zeroed_page(gfp_mask);
73 if (safe_needed)
Rafael J. Wysocki7be98232007-05-06 14:50:42 -070074 while (res && swsusp_page_is_free(virt_to_page(res))) {
Rafael J. Wysockif6143aa2006-09-25 23:32:50 -070075 /* The page is unsafe, mark it for swsusp_free() */
Rafael J. Wysocki7be98232007-05-06 14:50:42 -070076 swsusp_set_page_forbidden(virt_to_page(res));
Rafael J. Wysocki940864d2006-09-25 23:32:55 -070077 allocated_unsafe_pages++;
Rafael J. Wysockif6143aa2006-09-25 23:32:50 -070078 res = (void *)get_zeroed_page(gfp_mask);
79 }
80 if (res) {
Rafael J. Wysocki7be98232007-05-06 14:50:42 -070081 swsusp_set_page_forbidden(virt_to_page(res));
82 swsusp_set_page_free(virt_to_page(res));
Rafael J. Wysockif6143aa2006-09-25 23:32:50 -070083 }
84 return res;
85}
86
87unsigned long get_safe_page(gfp_t gfp_mask)
88{
Rafael J. Wysocki83573762006-12-06 20:34:18 -080089 return (unsigned long)get_image_page(gfp_mask, PG_SAFE);
90}
91
Rafael J. Wysocki5b6d15d2006-12-06 20:34:43 -080092static struct page *alloc_image_page(gfp_t gfp_mask)
93{
Rafael J. Wysocki83573762006-12-06 20:34:18 -080094 struct page *page;
95
96 page = alloc_page(gfp_mask);
97 if (page) {
Rafael J. Wysocki7be98232007-05-06 14:50:42 -070098 swsusp_set_page_forbidden(page);
99 swsusp_set_page_free(page);
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800100 }
101 return page;
Rafael J. Wysockif6143aa2006-09-25 23:32:50 -0700102}
103
104/**
105 * free_image_page - free page represented by @addr, allocated with
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800106 * get_image_page (page flags set by it must be cleared)
Rafael J. Wysockif6143aa2006-09-25 23:32:50 -0700107 */
108
109static inline void free_image_page(void *addr, int clear_nosave_free)
110{
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800111 struct page *page;
112
113 BUG_ON(!virt_addr_valid(addr));
114
115 page = virt_to_page(addr);
116
Rafael J. Wysocki7be98232007-05-06 14:50:42 -0700117 swsusp_unset_page_forbidden(page);
Rafael J. Wysockif6143aa2006-09-25 23:32:50 -0700118 if (clear_nosave_free)
Rafael J. Wysocki7be98232007-05-06 14:50:42 -0700119 swsusp_unset_page_free(page);
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800120
121 __free_page(page);
Rafael J. Wysockif6143aa2006-09-25 23:32:50 -0700122}
123
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700124/* struct linked_page is used to build chains of pages */
125
126#define LINKED_PAGE_DATA_SIZE (PAGE_SIZE - sizeof(void *))
127
128struct linked_page {
129 struct linked_page *next;
130 char data[LINKED_PAGE_DATA_SIZE];
131} __attribute__((packed));
132
133static inline void
134free_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
157struct 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
166static void
167chain_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
175static 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
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800182 lp = get_image_page(ca->gfp_mask, ca->safe_needed);
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700183 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
195static 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.
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700231 */
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
239struct 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
247struct 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
257struct bm_position {
258 struct zone_bitmap *zone_bm;
259 struct bm_block *block;
260 int chunk;
261 int bit;
262};
263
264struct 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
275static inline void memory_bm_reset_chunk(struct memory_bitmap *bm)
276{
277 bm->cur.chunk = 0;
278 bm->cur.bit = -1;
279}
280
281static 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
291static 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
297static inline struct bm_block *
298create_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
319static inline struct zone_bitmap *
320create_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
341static int
342memory_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;
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800354 for_each_zone(zone)
355 if (populated_zone(zone))
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700356 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 */
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800367 for_each_zone(zone) {
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700368 unsigned long pfn;
369
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800370 if (!populated_zone(zone))
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700371 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
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800389 ptr = get_image_page(gfp_mask, safe_needed);
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700390 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
Rafael J. Wysocki59a493352006-12-06 20:34:44 -0800413 Free:
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700414 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
423static 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/**
Rafael J. Wysocki74dfd662007-05-06 14:50:43 -0700445 * memory_bm_find_bit - find the bit in the bitmap @bm that corresponds
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700446 * to given pfn. The cur_zone_bm member of @bm and the cur_block member
447 * of @bm->cur_zone_bm are updated.
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700448 */
449
Rafael J. Wysocki74dfd662007-05-06 14:50:43 -0700450static void memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
451 void **addr, unsigned int *bit_nr)
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700452{
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;
Rafael J. Wysocki74dfd662007-05-06 14:50:43 -0700463
464 BUG_ON(!zone_bm);
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700465 }
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;
Rafael J. Wysocki74dfd662007-05-06 14:50:43 -0700475
476 BUG_ON(!bb);
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700477 }
478 zone_bm->cur_block = bb;
479 pfn -= bb->start_pfn;
Rafael J. Wysocki74dfd662007-05-06 14:50:43 -0700480 *bit_nr = pfn % BM_BITS_PER_CHUNK;
481 *addr = bb->data + pfn / BM_BITS_PER_CHUNK;
482}
483
484static 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
493static 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
502static 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);
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700509}
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
515static 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
529static 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
550static 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
Rafael J. Wysocki59a493352006-12-06 20:34:44 -0800584 Return_pfn:
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700585 bm->cur.chunk = chunk;
586 bm->cur.bit = bit;
587 return bb->start_pfn + chunk * BM_BITS_PER_CHUNK + bit;
588}
589
590/**
Rafael J. Wysocki74dfd662007-05-06 14:50:43 -0700591 * This structure represents a range of page frames the contents of which
592 * should not be saved during the suspend.
593 */
594
595struct nosave_region {
596 struct list_head list;
597 unsigned long start_pfn;
598 unsigned long end_pfn;
599};
600
601static 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
609void __init
Johannes Berg940d67f2007-05-08 19:23:49 +1000610__register_nosave_region(unsigned long start_pfn, unsigned long end_pfn,
611 int use_kmalloc)
Rafael J. Wysocki74dfd662007-05-06 14:50:43 -0700612{
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 }
Johannes Berg940d67f2007-05-08 19:23:49 +1000627 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));
Rafael J. Wysocki74dfd662007-05-06 14:50:43 -0700634 region->start_pfn = start_pfn;
635 region->end_pfn = end_pfn;
636 list_add_tail(&region->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 */
646static struct memory_bitmap *forbidden_pages_map;
647
648/* Set bits in this map correspond to free page frames. */
649static 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
656void 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
662static 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
668void 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
674static 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
680int 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
686static 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
697static 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++)
Rafael J. Wysockic5a69ad2007-08-10 13:00:57 -0700712 if (pfn_valid(pfn))
713 memory_bm_set_bit(bm, pfn);
Rafael J. Wysocki74dfd662007-05-06 14:50:43 -0700714 }
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
725int 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
Rafael J. Wysocki0709db62007-05-06 14:50:45 -0700732 bm1 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL);
Rafael J. Wysocki74dfd662007-05-06 14:50:43 -0700733 if (!bm1)
734 return -ENOMEM;
735
Rafael J. Wysocki0709db62007-05-06 14:50:45 -0700736 error = memory_bm_create(bm1, GFP_KERNEL, PG_ANY);
Rafael J. Wysocki74dfd662007-05-06 14:50:43 -0700737 if (error)
738 goto Free_first_object;
739
Rafael J. Wysocki0709db62007-05-06 14:50:45 -0700740 bm2 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL);
Rafael J. Wysocki74dfd662007-05-06 14:50:43 -0700741 if (!bm2)
742 goto Free_first_bitmap;
743
Rafael J. Wysocki0709db62007-05-06 14:50:45 -0700744 error = memory_bm_create(bm2, GFP_KERNEL, PG_ANY);
Rafael J. Wysocki74dfd662007-05-06 14:50:43 -0700745 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
772void 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
790/**
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700791 * 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
796unsigned 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);
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800802 return 2 * res;
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700803}
804
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800805#ifdef CONFIG_HIGHMEM
806/**
807 * count_free_highmem_pages - compute the total number of free highmem
808 * pages, system-wide.
809 */
810
811static 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))
Christoph Lameterd23ad422007-02-10 01:43:02 -0800818 cnt += zone_page_state(zone, NR_FREE_PAGES);
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800819
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
831static 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
Rafael J. Wysocki7be98232007-05-06 14:50:42 -0700842 if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page) ||
843 PageReserved(page))
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800844 return NULL;
845
846 return page;
847}
848
849/**
850 * count_highmem_pages - compute the total number of saveable highmem
851 * pages.
852 */
853
854unsigned 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
874static inline void *saveable_highmem_page(unsigned long pfn) { return NULL; }
875static inline unsigned int count_highmem_pages(void) { return 0; }
876#endif /* CONFIG_HIGHMEM */
877
Rafael J. Wysockif6143aa2006-09-25 23:32:50 -0700878/**
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800879 * saveable - Determine whether a non-highmem page should be included in
880 * the suspend image.
Rafael J. Wysocki25761b62005-10-30 14:59:56 -0800881 *
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800882 * 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.
Rafael J. Wysocki25761b62005-10-30 14:59:56 -0800885 */
886
Rafael J. Wysockiae83c5ee2006-09-25 23:32:45 -0700887static struct page *saveable_page(unsigned long pfn)
Rafael J. Wysocki25761b62005-10-30 14:59:56 -0800888{
Pavel Machekde491862005-10-30 14:59:59 -0800889 struct page *page;
Rafael J. Wysocki25761b62005-10-30 14:59:56 -0800890
891 if (!pfn_valid(pfn))
Rafael J. Wysockiae83c5ee2006-09-25 23:32:45 -0700892 return NULL;
Rafael J. Wysocki25761b62005-10-30 14:59:56 -0800893
894 page = pfn_to_page(pfn);
Rafael J. Wysocki25761b62005-10-30 14:59:56 -0800895
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800896 BUG_ON(PageHighMem(page));
897
Rafael J. Wysocki7be98232007-05-06 14:50:42 -0700898 if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page))
Rafael J. Wysockiae83c5ee2006-09-25 23:32:45 -0700899 return NULL;
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800900
Rafael J. Wysockiae83c5ee2006-09-25 23:32:45 -0700901 if (PageReserved(page) && pfn_is_nosave(pfn))
902 return NULL;
Rafael J. Wysockiae83c5ee2006-09-25 23:32:45 -0700903
904 return page;
Rafael J. Wysocki25761b62005-10-30 14:59:56 -0800905}
906
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800907/**
908 * count_data_pages - compute the total number of saveable non-highmem
909 * pages.
910 */
911
Rafael J. Wysocki72a97e02006-01-06 00:13:46 -0800912unsigned int count_data_pages(void)
Rafael J. Wysocki25761b62005-10-30 14:59:56 -0800913{
914 struct zone *zone;
Rafael J. Wysockiae83c5ee2006-09-25 23:32:45 -0700915 unsigned long pfn, max_zone_pfn;
Pavel Machekdc19d502005-11-07 00:58:40 -0800916 unsigned int n = 0;
Rafael J. Wysocki25761b62005-10-30 14:59:56 -0800917
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800918 for_each_zone(zone) {
Rafael J. Wysocki25761b62005-10-30 14:59:56 -0800919 if (is_highmem(zone))
920 continue;
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800921
Rafael J. Wysocki25761b62005-10-30 14:59:56 -0800922 mark_free_pages(zone);
Rafael J. Wysockiae83c5ee2006-09-25 23:32:45 -0700923 max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
924 for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800925 if(saveable_page(pfn))
926 n++;
Rafael J. Wysocki25761b62005-10-30 14:59:56 -0800927 }
Rafael J. Wysockia0f49652005-10-30 14:59:57 -0800928 return n;
Rafael J. Wysocki25761b62005-10-30 14:59:56 -0800929}
930
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800931/* This is needed, because copy_page and memcpy are not usable for copying
932 * task structs.
933 */
934static inline void do_copy_page(long *dst, long *src)
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -0700935{
936 int n;
937
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -0700938 for (n = PAGE_SIZE / sizeof(long); n; n--)
939 *dst++ = *src++;
940}
941
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800942#ifdef CONFIG_HIGHMEM
943static inline struct page *
944page_is_saveable(struct zone *zone, unsigned long pfn)
945{
946 return is_highmem(zone) ?
947 saveable_highmem_page(pfn) : saveable_page(pfn);
948}
949
950static inline void
951copy_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
983static inline void
984copy_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
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700991static void
992copy_data_pages(struct memory_bitmap *copy_bm, struct memory_bitmap *orig_bm)
Rafael J. Wysocki25761b62005-10-30 14:59:56 -0800993{
994 struct zone *zone;
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700995 unsigned long pfn;
Rafael J. Wysocki25761b62005-10-30 14:59:56 -0800996
Rafael J. Wysocki83573762006-12-06 20:34:18 -0800997 for_each_zone(zone) {
Rafael J. Wysockib788db72006-09-25 23:32:54 -0700998 unsigned long max_zone_pfn;
999
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001000 mark_free_pages(zone);
Rafael J. Wysockiae83c5ee2006-09-25 23:32:45 -07001001 max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001002 for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001003 if (page_is_saveable(zone, pfn))
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001004 memory_bm_set_bit(orig_bm, pfn);
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001005 }
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001006 memory_bm_position_reset(orig_bm);
1007 memory_bm_position_reset(copy_bm);
Fengguang Wudf7c4872007-10-20 02:26:04 +02001008 for(;;) {
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001009 pfn = memory_bm_next_pfn(orig_bm);
Fengguang Wudf7c4872007-10-20 02:26:04 +02001010 if (unlikely(pfn == BM_END_OF_MAP))
1011 break;
1012 copy_data_page(memory_bm_next_pfn(copy_bm), pfn);
1013 }
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001014}
1015
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001016/* Total number of image pages */
1017static unsigned int nr_copy_pages;
1018/* Number of pages needed for saving the original pfns of the image pages */
1019static unsigned int nr_meta_pages;
1020
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001021/**
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001022 * swsusp_free - free pages allocated for the suspend.
Rafael J. Wysockicd560bb2006-09-25 23:32:50 -07001023 *
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001024 * Suspend pages are alocated before the atomic copy is made, so we
1025 * need to release them after the resume.
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001026 */
1027
1028void swsusp_free(void)
1029{
1030 struct zone *zone;
Rafael J. Wysockiae83c5ee2006-09-25 23:32:45 -07001031 unsigned long pfn, max_zone_pfn;
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001032
1033 for_each_zone(zone) {
Rafael J. Wysockiae83c5ee2006-09-25 23:32:45 -07001034 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
Rafael J. Wysocki7be98232007-05-06 14:50:42 -07001039 if (swsusp_page_is_forbidden(page) &&
1040 swsusp_page_is_free(page)) {
1041 swsusp_unset_page_forbidden(page);
1042 swsusp_unset_page_free(page);
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001043 __free_page(page);
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001044 }
1045 }
1046 }
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001047 nr_copy_pages = 0;
1048 nr_meta_pages = 0;
Rafael J. Wysocki75534b52006-09-25 23:32:52 -07001049 restore_pblist = NULL;
Rafael J. Wysocki6e1819d2006-03-23 03:00:03 -08001050 buffer = NULL;
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001051}
1052
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001053#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
1059static 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
1071static unsigned int
1072count_pages_for_highmem(unsigned int nr_highmem) { return 0; }
1073#endif /* CONFIG_HIGHMEM */
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001074
1075/**
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001076 * enough_free_mem - Make sure we have enough free memory for the
1077 * snapshot image.
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001078 */
1079
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001080static int enough_free_mem(unsigned int nr_pages, unsigned int nr_highmem)
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001081{
Rafael J. Wysockie5e2fa72006-01-06 00:14:20 -08001082 struct zone *zone;
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001083 unsigned int free = 0, meta = 0;
Rafael J. Wysockie5e2fa72006-01-06 00:14:20 -08001084
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001085 for_each_zone(zone) {
1086 meta += snapshot_additional_pages(zone);
1087 if (!is_highmem(zone))
Christoph Lameterd23ad422007-02-10 01:43:02 -08001088 free += zone_page_state(zone, NR_FREE_PAGES);
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001089 }
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001090
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001091 nr_pages += count_pages_for_highmem(nr_highmem);
1092 pr_debug("swsusp: Normal pages needed: %u + %u + %u, available pages: %u\n",
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001093 nr_pages, PAGES_FOR_IO, meta, free);
1094
1095 return free > nr_pages + PAGES_FOR_IO + meta;
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001096}
1097
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001098#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
1104static 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
1116static inline unsigned int
1117alloc_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
1134static inline int get_highmem_buffer(int safe_needed) { return 0; }
1135
1136static inline unsigned int
1137alloc_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
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001152static int
1153swsusp_alloc(struct memory_bitmap *orig_bm, struct memory_bitmap *copy_bm,
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001154 unsigned int nr_pages, unsigned int nr_highmem)
Rafael J. Wysocki054bd4c2005-11-08 21:34:39 -08001155{
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001156 int error;
Rafael J. Wysocki054bd4c2005-11-08 21:34:39 -08001157
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001158 error = memory_bm_create(orig_bm, GFP_ATOMIC | __GFP_COLD, PG_ANY);
1159 if (error)
1160 goto Free;
1161
1162 error = memory_bm_create(copy_bm, GFP_ATOMIC | __GFP_COLD, PG_ANY);
1163 if (error)
1164 goto Free;
1165
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001166 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 }
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001173 while (nr_pages-- > 0) {
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001174 struct page *page = alloc_image_page(GFP_ATOMIC | __GFP_COLD);
1175
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001176 if (!page)
1177 goto Free;
1178
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001179 memory_bm_set_bit(copy_bm, page_to_pfn(page));
Rafael J. Wysocki054bd4c2005-11-08 21:34:39 -08001180 }
1181 return 0;
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001182
Rafael J. Wysocki59a493352006-12-06 20:34:44 -08001183 Free:
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001184 swsusp_free();
1185 return -ENOMEM;
Rafael J. Wysocki054bd4c2005-11-08 21:34:39 -08001186}
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001187
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001188/* Memory bitmap used for marking saveable pages (during suspend) or the
1189 * suspend image pages (during resume)
1190 */
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001191static struct memory_bitmap orig_bm;
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001192/* 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.
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001198 */
1199static struct memory_bitmap copy_bm;
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001200
Rafael J. Wysocki2e32a432005-10-30 15:00:00 -08001201asmlinkage int swsusp_save(void)
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001202{
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001203 unsigned int nr_pages, nr_highmem;
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001204
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001205 printk("swsusp: critical section: \n");
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001206
1207 drain_local_pages();
Rafael J. Wysockia0f49652005-10-30 14:59:57 -08001208 nr_pages = count_data_pages();
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001209 nr_highmem = count_highmem_pages();
1210 printk("swsusp: Need to copy %u pages\n", nr_pages + nr_highmem);
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001211
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001212 if (!enough_free_mem(nr_pages, nr_highmem)) {
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001213 printk(KERN_ERR "swsusp: Not enough free memory\n");
1214 return -ENOMEM;
1215 }
1216
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001217 if (swsusp_alloc(&orig_bm, &copy_bm, nr_pages, nr_highmem)) {
1218 printk(KERN_ERR "swsusp: Memory allocation failed\n");
Rafael J. Wysockia0f49652005-10-30 14:59:57 -08001219 return -ENOMEM;
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001220 }
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001221
1222 /* During allocating of suspend pagedir, new cold pages may appear.
1223 * Kill them.
1224 */
1225 drain_local_pages();
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001226 copy_data_pages(&copy_bm, &orig_bm);
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001227
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
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001234 nr_pages += nr_highmem;
Rafael J. Wysockia0f49652005-10-30 14:59:57 -08001235 nr_copy_pages = nr_pages;
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001236 nr_meta_pages = DIV_ROUND_UP(nr_pages * sizeof(long), PAGE_SIZE);
Rafael J. Wysockia0f49652005-10-30 14:59:57 -08001237
Andrew Mortond60846c2007-05-09 02:33:17 -07001238 printk("swsusp: critical section: done (%d pages copied)\n", nr_pages);
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001239
Rafael J. Wysocki25761b62005-10-30 14:59:56 -08001240 return 0;
1241}
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001242
Rafael J. Wysockid307c4a2007-10-18 03:04:52 -07001243#ifndef CONFIG_ARCH_HIBERNATION_HEADER
1244static int init_header_complete(struct swsusp_info *info)
1245{
1246 memcpy(&info->uts, init_utsname(), sizeof(struct new_utsname));
1247 info->version_code = LINUX_VERSION_CODE;
1248 return 0;
1249}
1250
1251static 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
1267static int init_header(struct swsusp_info *info)
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001268{
1269 memset(info, 0, sizeof(struct swsusp_info));
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001270 info->num_physpages = num_physpages;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001271 info->image_pages = nr_copy_pages;
1272 info->pages = nr_copy_pages + nr_meta_pages + 1;
Rafael J. Wysocki6e1819d2006-03-23 03:00:03 -08001273 info->size = info->pages;
1274 info->size <<= PAGE_SHIFT;
Rafael J. Wysockid307c4a2007-10-18 03:04:52 -07001275 return init_header_complete(info);
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001276}
1277
1278/**
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001279 * 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)
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001281 */
1282
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001283static inline void
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001284pack_pfns(unsigned long *buf, struct memory_bitmap *bm)
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001285{
1286 int j;
1287
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001288 for (j = 0; j < PAGE_SIZE / sizeof(long); j++) {
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001289 buf[j] = memory_bm_next_pfn(bm);
1290 if (unlikely(buf[j] == BM_END_OF_MAP))
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001291 break;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001292 }
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001293}
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
1317int snapshot_read_next(struct snapshot_handle *handle, size_t count)
1318{
Rafael J. Wysockifb13a282006-09-25 23:32:46 -07001319 if (handle->cur > nr_meta_pages + nr_copy_pages)
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001320 return 0;
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001321
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001322 if (!buffer) {
1323 /* This makes the buffer be freed by swsusp_free() */
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001324 buffer = get_image_page(GFP_ATOMIC, PG_ANY);
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001325 if (!buffer)
1326 return -ENOMEM;
1327 }
1328 if (!handle->offset) {
Rafael J. Wysockid307c4a2007-10-18 03:04:52 -07001329 int error;
1330
1331 error = init_header((struct swsusp_info *)buffer);
1332 if (error)
1333 return error;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001334 handle->buffer = buffer;
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001335 memory_bm_position_reset(&orig_bm);
1336 memory_bm_position_reset(&copy_bm);
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001337 }
Rafael J. Wysockifb13a282006-09-25 23:32:46 -07001338 if (handle->prev < handle->cur) {
1339 if (handle->cur <= nr_meta_pages) {
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001340 memset(buffer, 0, PAGE_SIZE);
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001341 pack_pfns(buffer, &orig_bm);
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001342 } else {
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001343 struct page *page;
Rafael J. Wysockib788db72006-09-25 23:32:54 -07001344
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001345 page = pfn_to_page(memory_bm_next_pfn(&copy_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 }
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001360 }
Rafael J. Wysockifb13a282006-09-25 23:32:46 -07001361 handle->prev = handle->cur;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001362 }
Rafael J. Wysockifb13a282006-09-25 23:32:46 -07001363 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++;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001368 } else {
Rafael J. Wysockifb13a282006-09-25 23:32:46 -07001369 handle->cur_offset += count;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001370 }
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
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001381static int mark_unsafe_pages(struct memory_bitmap *bm)
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001382{
1383 struct zone *zone;
Rafael J. Wysockiae83c5ee2006-09-25 23:32:45 -07001384 unsigned long pfn, max_zone_pfn;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001385
1386 /* Clear page flags */
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001387 for_each_zone(zone) {
Rafael J. Wysockiae83c5ee2006-09-25 23:32:45 -07001388 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))
Rafael J. Wysocki7be98232007-05-06 14:50:42 -07001391 swsusp_unset_page_free(pfn_to_page(pfn));
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001392 }
1393
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001394 /* 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)))
Rafael J. Wysocki7be98232007-05-06 14:50:42 -07001400 swsusp_set_page_free(pfn_to_page(pfn));
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001401 else
1402 return -EFAULT;
1403 }
1404 } while (pfn != BM_END_OF_MAP);
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001405
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001406 allocated_unsafe_pages = 0;
Rafael J. Wysocki968808b82006-06-23 02:04:48 -07001407
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001408 return 0;
1409}
1410
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001411static void
1412duplicate_memory_bitmap(struct memory_bitmap *dst, struct memory_bitmap *src)
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001413{
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001414 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);
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001421 }
1422}
1423
Rafael J. Wysockid307c4a2007-10-18 03:04:52 -07001424static int check_header(struct swsusp_info *info)
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001425{
Rafael J. Wysockid307c4a2007-10-18 03:04:52 -07001426 char *reason;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001427
Rafael J. Wysockid307c4a2007-10-18 03:04:52 -07001428 reason = check_image_kernel(info);
1429 if (!reason && info->num_physpages != num_physpages)
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001430 reason = "memory size";
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001431 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
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001442static int
1443load_header(struct swsusp_info *info)
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001444{
1445 int error;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001446
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001447 restore_pblist = NULL;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001448 error = check_header(info);
1449 if (!error) {
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001450 nr_copy_pages = info->image_pages;
1451 nr_meta_pages = info->pages - info->image_pages - 1;
1452 }
1453 return error;
1454}
1455
1456/**
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001457 * unpack_orig_pfns - for each element of @buf[] (1 page at a time) set
1458 * the corresponding bit in the memory bitmap @bm
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001459 */
1460
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001461static inline void
1462unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm)
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001463{
1464 int j;
1465
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001466 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]);
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001471 }
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001472}
1473
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001474/* List of "safe" pages that may be used to store data loaded from the suspend
1475 * image
1476 */
1477static 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 */
1484struct 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 */
1495static 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
1503static 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
1531static unsigned int safe_highmem_pages;
1532
1533static struct memory_bitmap *safe_highmem_bm;
1534
1535static int
1536prepare_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);
Rafael J. Wysocki7be98232007-05-06 14:50:42 -07001557 if (!swsusp_page_is_free(page)) {
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001558 /* 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 */
Rafael J. Wysocki7be98232007-05-06 14:50:42 -07001563 swsusp_set_page_forbidden(page);
1564 swsusp_set_page_free(page);
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001565 }
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
1588static struct page *last_highmem_page;
1589
1590static void *
1591get_highmem_page_buffer(struct page *page, struct chain_allocator *ca)
1592{
1593 struct highmem_pbe *pbe;
1594 void *kaddr;
1595
Rafael J. Wysocki7be98232007-05-06 14:50:42 -07001596 if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page)) {
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001597 /* 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
1638static 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
1650static inline int last_highmem_page_copied(void)
1651{
1652 return !last_highmem_page;
1653}
1654
1655static 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
1664static inline int get_safe_write_buffer(void) { return 0; }
1665
1666static unsigned int
1667count_highmem_image_pages(struct memory_bitmap *bm) { return 0; }
1668
1669static inline int
1670prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p)
1671{
1672 return 0;
1673}
1674
1675static inline void *
1676get_highmem_page_buffer(struct page *page, struct chain_allocator *ca)
1677{
1678 return NULL;
1679}
1680
1681static inline void copy_last_highmem_page(void) {}
1682static inline int last_highmem_page_copied(void) { return 1; }
1683static inline void free_highmem_data(void) {}
1684#endif /* CONFIG_HIGHMEM */
1685
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001686/**
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001687 * 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.
Rafael J. Wysocki968808b82006-06-23 02:04:48 -07001691 *
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001692 * 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
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001695 * 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.
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001698 */
1699
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001700#define PBES_PER_LINKED_PAGE (LINKED_PAGE_DATA_SIZE / sizeof(struct pbe))
Rafael J. Wysocki968808b82006-06-23 02:04:48 -07001701
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001702static int
1703prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm)
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001704{
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001705 unsigned int nr_pages, nr_highmem;
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001706 struct linked_page *sp_list, *lp;
1707 int error;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001708
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001709 /* 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);
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001714 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);
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001724 if (nr_highmem > 0) {
1725 error = prepare_highmem_image(bm, &nr_highmem);
1726 if (error)
1727 goto Free;
1728 }
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001729 /* 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 */
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001737 nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages;
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001738 nr_pages = DIV_ROUND_UP(nr_pages, PBES_PER_LINKED_PAGE);
1739 while (nr_pages > 0) {
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001740 lp = get_image_page(GFP_ATOMIC, PG_SAFE);
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001741 if (!lp) {
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001742 error = -ENOMEM;
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001743 goto Free;
Rafael J. Wysocki968808b82006-06-23 02:04:48 -07001744 }
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001745 lp->next = sp_list;
1746 sp_list = lp;
1747 nr_pages--;
Rafael J. Wysocki968808b82006-06-23 02:04:48 -07001748 }
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001749 /* Preallocate memory for the image */
1750 safe_pages_list = NULL;
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001751 nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages;
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001752 while (nr_pages > 0) {
1753 lp = (struct linked_page *)get_zeroed_page(GFP_ATOMIC);
1754 if (!lp) {
1755 error = -ENOMEM;
1756 goto Free;
1757 }
Rafael J. Wysocki7be98232007-05-06 14:50:42 -07001758 if (!swsusp_page_is_free(virt_to_page(lp))) {
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001759 /* The page is "safe", add it to the list */
1760 lp->next = safe_pages_list;
1761 safe_pages_list = lp;
1762 }
1763 /* Mark the page as allocated */
Rafael J. Wysocki7be98232007-05-06 14:50:42 -07001764 swsusp_set_page_forbidden(virt_to_page(lp));
1765 swsusp_set_page_free(virt_to_page(lp));
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001766 nr_pages--;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001767 }
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001768 /* 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;
1773 }
1774 return 0;
1775
Rafael J. Wysocki59a493352006-12-06 20:34:44 -08001776 Free:
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001777 swsusp_free();
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001778 return error;
1779}
1780
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001781/**
1782 * get_buffer - compute the address that snapshot_write_next() should
1783 * set for its caller to write to.
1784 */
Rafael J. Wysocki968808b82006-06-23 02:04:48 -07001785
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001786static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca)
1787{
1788 struct pbe *pbe;
1789 struct page *page = pfn_to_page(memory_bm_next_pfn(bm));
1790
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001791 if (PageHighMem(page))
1792 return get_highmem_page_buffer(page, ca);
1793
Rafael J. Wysocki7be98232007-05-06 14:50:42 -07001794 if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page))
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001795 /* We have allocated the "original" page frame and we can
1796 * use it directly to store the loaded page.
Rafael J. Wysocki968808b82006-06-23 02:04:48 -07001797 */
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001798 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.
Rafael J. Wysocki968808b82006-06-23 02:04:48 -07001802 */
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001803 pbe = chain_alloc(ca, sizeof(struct pbe));
1804 if (!pbe) {
1805 swsusp_free();
1806 return NULL;
1807 }
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001808 pbe->orig_address = page_address(page);
1809 pbe->address = safe_pages_list;
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001810 safe_pages_list = safe_pages_list->next;
1811 pbe->next = restore_pblist;
1812 restore_pblist = pbe;
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001813 return pbe->address;
Rafael J. Wysocki968808b82006-06-23 02:04:48 -07001814}
1815
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001816/**
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
1838int snapshot_write_next(struct snapshot_handle *handle, size_t count)
1839{
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001840 static struct chain_allocator ca;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001841 int error = 0;
1842
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001843 /* Check if we have already loaded the entire image */
Rafael J. Wysockifb13a282006-09-25 23:32:46 -07001844 if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages)
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001845 return 0;
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001846
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001847 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
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001852 if (!buffer)
1853 return -ENOMEM;
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001854
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001855 handle->buffer = buffer;
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001856 }
Andrew Morton546e0d22006-09-25 23:32:44 -07001857 handle->sync_read = 1;
Rafael J. Wysockifb13a282006-09-25 23:32:46 -07001858 if (handle->prev < handle->cur) {
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001859 if (handle->prev == 0) {
1860 error = load_header(buffer);
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001861 if (error)
1862 return error;
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001863
1864 error = memory_bm_create(&copy_bm, GFP_ATOMIC, PG_ANY);
1865 if (error)
1866 return error;
1867
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001868 } else if (handle->prev <= nr_meta_pages) {
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001869 unpack_orig_pfns(buffer, &copy_bm);
1870 if (handle->prev == nr_meta_pages) {
1871 error = prepare_image(&orig_bm, &copy_bm);
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001872 if (error)
1873 return error;
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001874
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);
Andrew Morton546e0d22006-09-25 23:32:44 -07001879 handle->sync_read = 0;
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001880 if (!handle->buffer)
1881 return -ENOMEM;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001882 }
1883 } else {
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001884 copy_last_highmem_page();
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001885 handle->buffer = get_buffer(&orig_bm, &ca);
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001886 if (handle->buffer != buffer)
1887 handle->sync_read = 0;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001888 }
Rafael J. Wysockifb13a282006-09-25 23:32:46 -07001889 handle->prev = handle->cur;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001890 }
Rafael J. Wysockifb13a282006-09-25 23:32:46 -07001891 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++;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001896 } else {
Rafael J. Wysockifb13a282006-09-25 23:32:46 -07001897 handle->cur_offset += count;
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001898 }
1899 handle->offset += count;
1900 return count;
1901}
1902
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001903/**
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
1911void 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
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001921int snapshot_image_loaded(struct snapshot_handle *handle)
1922{
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001923 return !(!nr_copy_pages || !last_highmem_page_copied() ||
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001924 handle->cur <= nr_meta_pages + nr_copy_pages);
1925}
1926
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001927#ifdef CONFIG_HIGHMEM
1928/* Assumes that @buf is ready and points to a "safe" page */
1929static inline void
1930swap_two_pages_data(struct page *p1, struct page *p2, void *buf)
Rafael J. Wysocki940864d2006-09-25 23:32:55 -07001931{
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001932 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);
Rafael J. Wysockif577eb32006-03-23 02:59:59 -08001941}
Rafael J. Wysocki83573762006-12-06 20:34:18 -08001942
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
1953int 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;
1971}
1972#endif /* CONFIG_HIGHMEM */