Commit | Line | Data |
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25761b6e | 1 | /* |
96bc7aec | 2 | * linux/kernel/power/snapshot.c |
25761b6e | 3 | * |
96bc7aec | 4 | * This file provide system snapshot/restore functionality. |
25761b6e RW |
5 | * |
6 | * Copyright (C) 1998-2005 Pavel Machek <pavel@suse.cz> | |
7 | * | |
8 | * This file is released under the GPLv2, and is based on swsusp.c. | |
9 | * | |
10 | */ | |
11 | ||
12 | ||
13 | #include <linux/module.h> | |
14 | #include <linux/mm.h> | |
15 | #include <linux/suspend.h> | |
16 | #include <linux/smp_lock.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> | |
25761b6e RW |
23 | #include <linux/bootmem.h> |
24 | #include <linux/syscalls.h> | |
25 | #include <linux/console.h> | |
26 | #include <linux/highmem.h> | |
25761b6e RW |
27 | |
28 | #include <asm/uaccess.h> | |
29 | #include <asm/mmu_context.h> | |
30 | #include <asm/pgtable.h> | |
31 | #include <asm/tlbflush.h> | |
32 | #include <asm/io.h> | |
33 | ||
25761b6e RW |
34 | #include "power.h" |
35 | ||
25761b6e RW |
36 | #ifdef CONFIG_HIGHMEM |
37 | struct highmem_page { | |
38 | char *data; | |
39 | struct page *page; | |
40 | struct highmem_page *next; | |
41 | }; | |
42 | ||
43 | static struct highmem_page *highmem_copy; | |
44 | ||
45 | static int save_highmem_zone(struct zone *zone) | |
46 | { | |
47 | unsigned long zone_pfn; | |
48 | mark_free_pages(zone); | |
49 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) { | |
50 | struct page *page; | |
51 | struct highmem_page *save; | |
52 | void *kaddr; | |
53 | unsigned long pfn = zone_pfn + zone->zone_start_pfn; | |
54 | ||
55 | if (!(pfn%1000)) | |
56 | printk("."); | |
57 | if (!pfn_valid(pfn)) | |
58 | continue; | |
59 | page = pfn_to_page(pfn); | |
60 | /* | |
61 | * This condition results from rvmalloc() sans vmalloc_32() | |
62 | * and architectural memory reservations. This should be | |
63 | * corrected eventually when the cases giving rise to this | |
64 | * are better understood. | |
65 | */ | |
66 | if (PageReserved(page)) { | |
67 | printk("highmem reserved page?!\n"); | |
68 | continue; | |
69 | } | |
70 | BUG_ON(PageNosave(page)); | |
71 | if (PageNosaveFree(page)) | |
72 | continue; | |
73 | save = kmalloc(sizeof(struct highmem_page), GFP_ATOMIC); | |
74 | if (!save) | |
75 | return -ENOMEM; | |
76 | save->next = highmem_copy; | |
77 | save->page = page; | |
78 | save->data = (void *) get_zeroed_page(GFP_ATOMIC); | |
79 | if (!save->data) { | |
80 | kfree(save); | |
81 | return -ENOMEM; | |
82 | } | |
83 | kaddr = kmap_atomic(page, KM_USER0); | |
84 | memcpy(save->data, kaddr, PAGE_SIZE); | |
85 | kunmap_atomic(kaddr, KM_USER0); | |
86 | highmem_copy = save; | |
87 | } | |
88 | return 0; | |
89 | } | |
25761b6e | 90 | |
0fbeb5a4 | 91 | int save_highmem(void) |
25761b6e | 92 | { |
25761b6e RW |
93 | struct zone *zone; |
94 | int res = 0; | |
95 | ||
96 | pr_debug("swsusp: Saving Highmem\n"); | |
97 | for_each_zone (zone) { | |
98 | if (is_highmem(zone)) | |
99 | res = save_highmem_zone(zone); | |
100 | if (res) | |
101 | return res; | |
102 | } | |
25761b6e RW |
103 | return 0; |
104 | } | |
105 | ||
106 | int restore_highmem(void) | |
107 | { | |
25761b6e RW |
108 | printk("swsusp: Restoring Highmem\n"); |
109 | while (highmem_copy) { | |
110 | struct highmem_page *save = highmem_copy; | |
111 | void *kaddr; | |
112 | highmem_copy = save->next; | |
113 | ||
114 | kaddr = kmap_atomic(save->page, KM_USER0); | |
115 | memcpy(kaddr, save->data, PAGE_SIZE); | |
116 | kunmap_atomic(kaddr, KM_USER0); | |
117 | free_page((long) save->data); | |
118 | kfree(save); | |
119 | } | |
25761b6e RW |
120 | return 0; |
121 | } | |
0fbeb5a4 | 122 | #endif |
25761b6e RW |
123 | |
124 | static int pfn_is_nosave(unsigned long pfn) | |
125 | { | |
126 | unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT; | |
127 | unsigned long nosave_end_pfn = PAGE_ALIGN(__pa(&__nosave_end)) >> PAGE_SHIFT; | |
128 | return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn); | |
129 | } | |
130 | ||
131 | /** | |
132 | * saveable - Determine whether a page should be cloned or not. | |
133 | * @pfn: The page | |
134 | * | |
135 | * We save a page if it's Reserved, and not in the range of pages | |
136 | * statically defined as 'unsaveable', or if it isn't reserved, and | |
137 | * isn't part of a free chunk of pages. | |
138 | */ | |
139 | ||
de491861 | 140 | static int saveable(struct zone *zone, unsigned long *zone_pfn) |
25761b6e RW |
141 | { |
142 | unsigned long pfn = *zone_pfn + zone->zone_start_pfn; | |
de491861 | 143 | struct page *page; |
25761b6e RW |
144 | |
145 | if (!pfn_valid(pfn)) | |
146 | return 0; | |
147 | ||
148 | page = pfn_to_page(pfn); | |
149 | BUG_ON(PageReserved(page) && PageNosave(page)); | |
150 | if (PageNosave(page)) | |
151 | return 0; | |
152 | if (PageReserved(page) && pfn_is_nosave(pfn)) { | |
153 | pr_debug("[nosave pfn 0x%lx]", pfn); | |
154 | return 0; | |
155 | } | |
156 | if (PageNosaveFree(page)) | |
157 | return 0; | |
158 | ||
159 | return 1; | |
160 | } | |
161 | ||
a0f49651 | 162 | static unsigned count_data_pages(void) |
25761b6e RW |
163 | { |
164 | struct zone *zone; | |
165 | unsigned long zone_pfn; | |
dc19d507 | 166 | unsigned int n = 0; |
25761b6e | 167 | |
25761b6e RW |
168 | for_each_zone (zone) { |
169 | if (is_highmem(zone)) | |
170 | continue; | |
171 | mark_free_pages(zone); | |
172 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) | |
a0f49651 | 173 | n += saveable(zone, &zone_pfn); |
25761b6e | 174 | } |
a0f49651 | 175 | return n; |
25761b6e RW |
176 | } |
177 | ||
a0f49651 | 178 | static void copy_data_pages(struct pbe *pblist) |
25761b6e RW |
179 | { |
180 | struct zone *zone; | |
181 | unsigned long zone_pfn; | |
a0f49651 | 182 | struct pbe *pbe, *p; |
25761b6e | 183 | |
a0f49651 | 184 | pbe = pblist; |
25761b6e RW |
185 | for_each_zone (zone) { |
186 | if (is_highmem(zone)) | |
187 | continue; | |
188 | mark_free_pages(zone); | |
189 | /* This is necessary for swsusp_free() */ | |
a0f49651 | 190 | for_each_pb_page (p, pblist) |
25761b6e | 191 | SetPageNosaveFree(virt_to_page(p)); |
a0f49651 | 192 | for_each_pbe (p, pblist) |
25761b6e RW |
193 | SetPageNosaveFree(virt_to_page(p->address)); |
194 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) { | |
195 | if (saveable(zone, &zone_pfn)) { | |
de491861 | 196 | struct page *page; |
25761b6e RW |
197 | page = pfn_to_page(zone_pfn + zone->zone_start_pfn); |
198 | BUG_ON(!pbe); | |
199 | pbe->orig_address = (unsigned long)page_address(page); | |
200 | /* copy_page is not usable for copying task structs. */ | |
201 | memcpy((void *)pbe->address, (void *)pbe->orig_address, PAGE_SIZE); | |
202 | pbe = pbe->next; | |
203 | } | |
204 | } | |
205 | } | |
206 | BUG_ON(pbe); | |
207 | } | |
208 | ||
209 | ||
210 | /** | |
211 | * free_pagedir - free pages allocated with alloc_pagedir() | |
212 | */ | |
213 | ||
ed14b527 | 214 | void free_pagedir(struct pbe *pblist) |
25761b6e RW |
215 | { |
216 | struct pbe *pbe; | |
217 | ||
218 | while (pblist) { | |
219 | pbe = (pblist + PB_PAGE_SKIP)->next; | |
220 | ClearPageNosave(virt_to_page(pblist)); | |
221 | ClearPageNosaveFree(virt_to_page(pblist)); | |
222 | free_page((unsigned long)pblist); | |
223 | pblist = pbe; | |
224 | } | |
225 | } | |
226 | ||
227 | /** | |
228 | * fill_pb_page - Create a list of PBEs on a given memory page | |
229 | */ | |
230 | ||
231 | static inline void fill_pb_page(struct pbe *pbpage) | |
232 | { | |
233 | struct pbe *p; | |
234 | ||
235 | p = pbpage; | |
236 | pbpage += PB_PAGE_SKIP; | |
237 | do | |
238 | p->next = p + 1; | |
239 | while (++p < pbpage); | |
240 | } | |
241 | ||
242 | /** | |
243 | * create_pbe_list - Create a list of PBEs on top of a given chain | |
244 | * of memory pages allocated with alloc_pagedir() | |
245 | */ | |
246 | ||
dc19d507 | 247 | void create_pbe_list(struct pbe *pblist, unsigned int nr_pages) |
25761b6e RW |
248 | { |
249 | struct pbe *pbpage, *p; | |
dc19d507 | 250 | unsigned int num = PBES_PER_PAGE; |
25761b6e RW |
251 | |
252 | for_each_pb_page (pbpage, pblist) { | |
253 | if (num >= nr_pages) | |
254 | break; | |
255 | ||
256 | fill_pb_page(pbpage); | |
257 | num += PBES_PER_PAGE; | |
258 | } | |
259 | if (pbpage) { | |
260 | for (num -= PBES_PER_PAGE - 1, p = pbpage; num < nr_pages; p++, num++) | |
261 | p->next = p + 1; | |
262 | p->next = NULL; | |
263 | } | |
264 | pr_debug("create_pbe_list(): initialized %d PBEs\n", num); | |
265 | } | |
266 | ||
054bd4c1 RW |
267 | /** |
268 | * @safe_needed - on resume, for storing the PBE list and the image, | |
269 | * we can only use memory pages that do not conflict with the pages | |
270 | * which had been used before suspend. | |
271 | * | |
272 | * The unsafe pages are marked with the PG_nosave_free flag | |
273 | * | |
274 | * Allocated but unusable (ie eaten) memory pages should be marked | |
275 | * so that swsusp_free() can release them | |
276 | */ | |
277 | ||
278 | static inline void *alloc_image_page(gfp_t gfp_mask, int safe_needed) | |
25761b6e | 279 | { |
054bd4c1 RW |
280 | void *res; |
281 | ||
282 | if (safe_needed) | |
283 | do { | |
284 | res = (void *)get_zeroed_page(gfp_mask); | |
285 | if (res && PageNosaveFree(virt_to_page(res))) | |
286 | /* This is for swsusp_free() */ | |
287 | SetPageNosave(virt_to_page(res)); | |
288 | } while (res && PageNosaveFree(virt_to_page(res))); | |
289 | else | |
290 | res = (void *)get_zeroed_page(gfp_mask); | |
25761b6e RW |
291 | if (res) { |
292 | SetPageNosave(virt_to_page(res)); | |
293 | SetPageNosaveFree(virt_to_page(res)); | |
294 | } | |
295 | return res; | |
296 | } | |
297 | ||
054bd4c1 RW |
298 | unsigned long get_safe_page(gfp_t gfp_mask) |
299 | { | |
300 | return (unsigned long)alloc_image_page(gfp_mask, 1); | |
301 | } | |
302 | ||
25761b6e RW |
303 | /** |
304 | * alloc_pagedir - Allocate the page directory. | |
305 | * | |
306 | * First, determine exactly how many pages we need and | |
307 | * allocate them. | |
308 | * | |
309 | * We arrange the pages in a chain: each page is an array of PBES_PER_PAGE | |
310 | * struct pbe elements (pbes) and the last element in the page points | |
311 | * to the next page. | |
312 | * | |
313 | * On each page we set up a list of struct_pbe elements. | |
314 | */ | |
315 | ||
054bd4c1 | 316 | struct pbe *alloc_pagedir(unsigned int nr_pages, gfp_t gfp_mask, int safe_needed) |
25761b6e | 317 | { |
dc19d507 | 318 | unsigned int num; |
25761b6e RW |
319 | struct pbe *pblist, *pbe; |
320 | ||
321 | if (!nr_pages) | |
322 | return NULL; | |
323 | ||
324 | pr_debug("alloc_pagedir(): nr_pages = %d\n", nr_pages); | |
054bd4c1 | 325 | pblist = alloc_image_page(gfp_mask, safe_needed); |
25761b6e RW |
326 | /* FIXME: rewrite this ugly loop */ |
327 | for (pbe = pblist, num = PBES_PER_PAGE; pbe && num < nr_pages; | |
328 | pbe = pbe->next, num += PBES_PER_PAGE) { | |
329 | pbe += PB_PAGE_SKIP; | |
054bd4c1 | 330 | pbe->next = alloc_image_page(gfp_mask, safe_needed); |
25761b6e RW |
331 | } |
332 | if (!pbe) { /* get_zeroed_page() failed */ | |
333 | free_pagedir(pblist); | |
334 | pblist = NULL; | |
335 | } | |
336 | return pblist; | |
337 | } | |
338 | ||
339 | /** | |
340 | * Free pages we allocated for suspend. Suspend pages are alocated | |
341 | * before atomic copy, so we need to free them after resume. | |
342 | */ | |
343 | ||
344 | void swsusp_free(void) | |
345 | { | |
346 | struct zone *zone; | |
347 | unsigned long zone_pfn; | |
348 | ||
349 | for_each_zone(zone) { | |
350 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) | |
351 | if (pfn_valid(zone_pfn + zone->zone_start_pfn)) { | |
dc19d507 | 352 | struct page *page; |
25761b6e RW |
353 | page = pfn_to_page(zone_pfn + zone->zone_start_pfn); |
354 | if (PageNosave(page) && PageNosaveFree(page)) { | |
355 | ClearPageNosave(page); | |
356 | ClearPageNosaveFree(page); | |
357 | free_page((long) page_address(page)); | |
358 | } | |
359 | } | |
360 | } | |
361 | } | |
362 | ||
363 | ||
364 | /** | |
365 | * enough_free_mem - Make sure we enough free memory to snapshot. | |
366 | * | |
367 | * Returns TRUE or FALSE after checking the number of available | |
368 | * free pages. | |
369 | */ | |
370 | ||
dc19d507 | 371 | static int enough_free_mem(unsigned int nr_pages) |
25761b6e RW |
372 | { |
373 | pr_debug("swsusp: available memory: %u pages\n", nr_free_pages()); | |
a0f49651 RW |
374 | return nr_free_pages() > (nr_pages + PAGES_FOR_IO + |
375 | (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE); | |
25761b6e RW |
376 | } |
377 | ||
054bd4c1 RW |
378 | int alloc_data_pages(struct pbe *pblist, gfp_t gfp_mask, int safe_needed) |
379 | { | |
380 | struct pbe *p; | |
381 | ||
382 | for_each_pbe (p, pblist) { | |
383 | p->address = (unsigned long)alloc_image_page(gfp_mask, safe_needed); | |
384 | if (!p->address) | |
385 | return -ENOMEM; | |
386 | } | |
387 | return 0; | |
388 | } | |
25761b6e | 389 | |
dc19d507 | 390 | static struct pbe *swsusp_alloc(unsigned int nr_pages) |
25761b6e | 391 | { |
054bd4c1 | 392 | struct pbe *pblist; |
25761b6e | 393 | |
054bd4c1 | 394 | if (!(pblist = alloc_pagedir(nr_pages, GFP_ATOMIC | __GFP_COLD, 0))) { |
25761b6e | 395 | printk(KERN_ERR "suspend: Allocating pagedir failed.\n"); |
a0f49651 | 396 | return NULL; |
25761b6e | 397 | } |
a0f49651 | 398 | create_pbe_list(pblist, nr_pages); |
25761b6e | 399 | |
054bd4c1 RW |
400 | if (alloc_data_pages(pblist, GFP_ATOMIC | __GFP_COLD, 0)) { |
401 | printk(KERN_ERR "suspend: Allocating image pages failed.\n"); | |
402 | swsusp_free(); | |
403 | return NULL; | |
25761b6e RW |
404 | } |
405 | ||
a0f49651 | 406 | return pblist; |
25761b6e RW |
407 | } |
408 | ||
2e32a43e | 409 | asmlinkage int swsusp_save(void) |
25761b6e | 410 | { |
dc19d507 | 411 | unsigned int nr_pages; |
25761b6e RW |
412 | |
413 | pr_debug("swsusp: critical section: \n"); | |
25761b6e RW |
414 | |
415 | drain_local_pages(); | |
a0f49651 RW |
416 | nr_pages = count_data_pages(); |
417 | printk("swsusp: Need to copy %u pages\n", nr_pages); | |
25761b6e RW |
418 | |
419 | pr_debug("swsusp: pages needed: %u + %lu + %u, free: %u\n", | |
a0f49651 RW |
420 | nr_pages, |
421 | (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE, | |
25761b6e RW |
422 | PAGES_FOR_IO, nr_free_pages()); |
423 | ||
a0f49651 RW |
424 | /* This is needed because of the fixed size of swsusp_info */ |
425 | if (MAX_PBES < (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE) | |
426 | return -ENOSPC; | |
427 | ||
428 | if (!enough_free_mem(nr_pages)) { | |
25761b6e RW |
429 | printk(KERN_ERR "swsusp: Not enough free memory\n"); |
430 | return -ENOMEM; | |
431 | } | |
432 | ||
a0f49651 RW |
433 | pagedir_nosave = swsusp_alloc(nr_pages); |
434 | if (!pagedir_nosave) | |
435 | return -ENOMEM; | |
25761b6e RW |
436 | |
437 | /* During allocating of suspend pagedir, new cold pages may appear. | |
438 | * Kill them. | |
439 | */ | |
440 | drain_local_pages(); | |
a0f49651 | 441 | copy_data_pages(pagedir_nosave); |
25761b6e RW |
442 | |
443 | /* | |
444 | * End of critical section. From now on, we can write to memory, | |
445 | * but we should not touch disk. This specially means we must _not_ | |
446 | * touch swap space! Except we must write out our image of course. | |
447 | */ | |
448 | ||
a0f49651 RW |
449 | nr_copy_pages = nr_pages; |
450 | ||
451 | printk("swsusp: critical section/: done (%d pages copied)\n", nr_pages); | |
25761b6e RW |
452 | return 0; |
453 | } |