]>
Commit | Line | Data |
---|---|---|
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 | ||
36 | ||
25761b6e RW |
37 | #ifdef CONFIG_HIGHMEM |
38 | struct highmem_page { | |
39 | char *data; | |
40 | struct page *page; | |
41 | struct highmem_page *next; | |
42 | }; | |
43 | ||
44 | static struct highmem_page *highmem_copy; | |
45 | ||
46 | static int save_highmem_zone(struct zone *zone) | |
47 | { | |
48 | unsigned long zone_pfn; | |
49 | mark_free_pages(zone); | |
50 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) { | |
51 | struct page *page; | |
52 | struct highmem_page *save; | |
53 | void *kaddr; | |
54 | unsigned long pfn = zone_pfn + zone->zone_start_pfn; | |
55 | ||
56 | if (!(pfn%1000)) | |
57 | printk("."); | |
58 | if (!pfn_valid(pfn)) | |
59 | continue; | |
60 | page = pfn_to_page(pfn); | |
61 | /* | |
62 | * This condition results from rvmalloc() sans vmalloc_32() | |
63 | * and architectural memory reservations. This should be | |
64 | * corrected eventually when the cases giving rise to this | |
65 | * are better understood. | |
66 | */ | |
67 | if (PageReserved(page)) { | |
68 | printk("highmem reserved page?!\n"); | |
69 | continue; | |
70 | } | |
71 | BUG_ON(PageNosave(page)); | |
72 | if (PageNosaveFree(page)) | |
73 | continue; | |
74 | save = kmalloc(sizeof(struct highmem_page), GFP_ATOMIC); | |
75 | if (!save) | |
76 | return -ENOMEM; | |
77 | save->next = highmem_copy; | |
78 | save->page = page; | |
79 | save->data = (void *) get_zeroed_page(GFP_ATOMIC); | |
80 | if (!save->data) { | |
81 | kfree(save); | |
82 | return -ENOMEM; | |
83 | } | |
84 | kaddr = kmap_atomic(page, KM_USER0); | |
85 | memcpy(save->data, kaddr, PAGE_SIZE); | |
86 | kunmap_atomic(kaddr, KM_USER0); | |
87 | highmem_copy = save; | |
88 | } | |
89 | return 0; | |
90 | } | |
91 | #endif /* CONFIG_HIGHMEM */ | |
92 | ||
93 | ||
94 | static int save_highmem(void) | |
95 | { | |
96 | #ifdef CONFIG_HIGHMEM | |
97 | struct zone *zone; | |
98 | int res = 0; | |
99 | ||
100 | pr_debug("swsusp: Saving Highmem\n"); | |
101 | for_each_zone (zone) { | |
102 | if (is_highmem(zone)) | |
103 | res = save_highmem_zone(zone); | |
104 | if (res) | |
105 | return res; | |
106 | } | |
107 | #endif | |
108 | return 0; | |
109 | } | |
110 | ||
111 | int restore_highmem(void) | |
112 | { | |
113 | #ifdef CONFIG_HIGHMEM | |
114 | printk("swsusp: Restoring Highmem\n"); | |
115 | while (highmem_copy) { | |
116 | struct highmem_page *save = highmem_copy; | |
117 | void *kaddr; | |
118 | highmem_copy = save->next; | |
119 | ||
120 | kaddr = kmap_atomic(save->page, KM_USER0); | |
121 | memcpy(kaddr, save->data, PAGE_SIZE); | |
122 | kunmap_atomic(kaddr, KM_USER0); | |
123 | free_page((long) save->data); | |
124 | kfree(save); | |
125 | } | |
126 | #endif | |
127 | return 0; | |
128 | } | |
129 | ||
130 | ||
131 | static int pfn_is_nosave(unsigned long pfn) | |
132 | { | |
133 | unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT; | |
134 | unsigned long nosave_end_pfn = PAGE_ALIGN(__pa(&__nosave_end)) >> PAGE_SHIFT; | |
135 | return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn); | |
136 | } | |
137 | ||
138 | /** | |
139 | * saveable - Determine whether a page should be cloned or not. | |
140 | * @pfn: The page | |
141 | * | |
142 | * We save a page if it's Reserved, and not in the range of pages | |
143 | * statically defined as 'unsaveable', or if it isn't reserved, and | |
144 | * isn't part of a free chunk of pages. | |
145 | */ | |
146 | ||
147 | static int saveable(struct zone * zone, unsigned long * zone_pfn) | |
148 | { | |
149 | unsigned long pfn = *zone_pfn + zone->zone_start_pfn; | |
150 | struct page * page; | |
151 | ||
152 | if (!pfn_valid(pfn)) | |
153 | return 0; | |
154 | ||
155 | page = pfn_to_page(pfn); | |
156 | BUG_ON(PageReserved(page) && PageNosave(page)); | |
157 | if (PageNosave(page)) | |
158 | return 0; | |
159 | if (PageReserved(page) && pfn_is_nosave(pfn)) { | |
160 | pr_debug("[nosave pfn 0x%lx]", pfn); | |
161 | return 0; | |
162 | } | |
163 | if (PageNosaveFree(page)) | |
164 | return 0; | |
165 | ||
166 | return 1; | |
167 | } | |
168 | ||
a0f49651 | 169 | static unsigned count_data_pages(void) |
25761b6e RW |
170 | { |
171 | struct zone *zone; | |
172 | unsigned long zone_pfn; | |
a0f49651 | 173 | unsigned n; |
25761b6e | 174 | |
a0f49651 | 175 | n = 0; |
25761b6e RW |
176 | for_each_zone (zone) { |
177 | if (is_highmem(zone)) | |
178 | continue; | |
179 | mark_free_pages(zone); | |
180 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) | |
a0f49651 | 181 | n += saveable(zone, &zone_pfn); |
25761b6e | 182 | } |
a0f49651 | 183 | return n; |
25761b6e RW |
184 | } |
185 | ||
a0f49651 | 186 | static void copy_data_pages(struct pbe *pblist) |
25761b6e RW |
187 | { |
188 | struct zone *zone; | |
189 | unsigned long zone_pfn; | |
a0f49651 | 190 | struct pbe *pbe, *p; |
25761b6e | 191 | |
a0f49651 | 192 | pbe = pblist; |
25761b6e RW |
193 | for_each_zone (zone) { |
194 | if (is_highmem(zone)) | |
195 | continue; | |
196 | mark_free_pages(zone); | |
197 | /* This is necessary for swsusp_free() */ | |
a0f49651 | 198 | for_each_pb_page (p, pblist) |
25761b6e | 199 | SetPageNosaveFree(virt_to_page(p)); |
a0f49651 | 200 | for_each_pbe (p, pblist) |
25761b6e RW |
201 | SetPageNosaveFree(virt_to_page(p->address)); |
202 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) { | |
203 | if (saveable(zone, &zone_pfn)) { | |
204 | struct page * page; | |
205 | page = pfn_to_page(zone_pfn + zone->zone_start_pfn); | |
206 | BUG_ON(!pbe); | |
207 | pbe->orig_address = (unsigned long)page_address(page); | |
208 | /* copy_page is not usable for copying task structs. */ | |
209 | memcpy((void *)pbe->address, (void *)pbe->orig_address, PAGE_SIZE); | |
210 | pbe = pbe->next; | |
211 | } | |
212 | } | |
213 | } | |
214 | BUG_ON(pbe); | |
215 | } | |
216 | ||
217 | ||
218 | /** | |
219 | * free_pagedir - free pages allocated with alloc_pagedir() | |
220 | */ | |
221 | ||
2c1b4a5c | 222 | static void free_pagedir(struct pbe *pblist) |
25761b6e RW |
223 | { |
224 | struct pbe *pbe; | |
225 | ||
226 | while (pblist) { | |
227 | pbe = (pblist + PB_PAGE_SKIP)->next; | |
228 | ClearPageNosave(virt_to_page(pblist)); | |
229 | ClearPageNosaveFree(virt_to_page(pblist)); | |
230 | free_page((unsigned long)pblist); | |
231 | pblist = pbe; | |
232 | } | |
233 | } | |
234 | ||
235 | /** | |
236 | * fill_pb_page - Create a list of PBEs on a given memory page | |
237 | */ | |
238 | ||
239 | static inline void fill_pb_page(struct pbe *pbpage) | |
240 | { | |
241 | struct pbe *p; | |
242 | ||
243 | p = pbpage; | |
244 | pbpage += PB_PAGE_SKIP; | |
245 | do | |
246 | p->next = p + 1; | |
247 | while (++p < pbpage); | |
248 | } | |
249 | ||
250 | /** | |
251 | * create_pbe_list - Create a list of PBEs on top of a given chain | |
252 | * of memory pages allocated with alloc_pagedir() | |
253 | */ | |
254 | ||
255 | void create_pbe_list(struct pbe *pblist, unsigned nr_pages) | |
256 | { | |
257 | struct pbe *pbpage, *p; | |
258 | unsigned num = PBES_PER_PAGE; | |
259 | ||
260 | for_each_pb_page (pbpage, pblist) { | |
261 | if (num >= nr_pages) | |
262 | break; | |
263 | ||
264 | fill_pb_page(pbpage); | |
265 | num += PBES_PER_PAGE; | |
266 | } | |
267 | if (pbpage) { | |
268 | for (num -= PBES_PER_PAGE - 1, p = pbpage; num < nr_pages; p++, num++) | |
269 | p->next = p + 1; | |
270 | p->next = NULL; | |
271 | } | |
272 | pr_debug("create_pbe_list(): initialized %d PBEs\n", num); | |
273 | } | |
274 | ||
275 | static void *alloc_image_page(void) | |
276 | { | |
277 | void *res = (void *)get_zeroed_page(GFP_ATOMIC | __GFP_COLD); | |
278 | if (res) { | |
279 | SetPageNosave(virt_to_page(res)); | |
280 | SetPageNosaveFree(virt_to_page(res)); | |
281 | } | |
282 | return res; | |
283 | } | |
284 | ||
285 | /** | |
286 | * alloc_pagedir - Allocate the page directory. | |
287 | * | |
288 | * First, determine exactly how many pages we need and | |
289 | * allocate them. | |
290 | * | |
291 | * We arrange the pages in a chain: each page is an array of PBES_PER_PAGE | |
292 | * struct pbe elements (pbes) and the last element in the page points | |
293 | * to the next page. | |
294 | * | |
295 | * On each page we set up a list of struct_pbe elements. | |
296 | */ | |
297 | ||
298 | struct pbe * alloc_pagedir(unsigned nr_pages) | |
299 | { | |
300 | unsigned num; | |
301 | struct pbe *pblist, *pbe; | |
302 | ||
303 | if (!nr_pages) | |
304 | return NULL; | |
305 | ||
306 | pr_debug("alloc_pagedir(): nr_pages = %d\n", nr_pages); | |
307 | pblist = (struct pbe *)alloc_image_page(); | |
308 | /* FIXME: rewrite this ugly loop */ | |
309 | for (pbe = pblist, num = PBES_PER_PAGE; pbe && num < nr_pages; | |
310 | pbe = pbe->next, num += PBES_PER_PAGE) { | |
311 | pbe += PB_PAGE_SKIP; | |
312 | pbe->next = (struct pbe *)alloc_image_page(); | |
313 | } | |
314 | if (!pbe) { /* get_zeroed_page() failed */ | |
315 | free_pagedir(pblist); | |
316 | pblist = NULL; | |
317 | } | |
318 | return pblist; | |
319 | } | |
320 | ||
321 | /** | |
322 | * Free pages we allocated for suspend. Suspend pages are alocated | |
323 | * before atomic copy, so we need to free them after resume. | |
324 | */ | |
325 | ||
326 | void swsusp_free(void) | |
327 | { | |
328 | struct zone *zone; | |
329 | unsigned long zone_pfn; | |
330 | ||
331 | for_each_zone(zone) { | |
332 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) | |
333 | if (pfn_valid(zone_pfn + zone->zone_start_pfn)) { | |
334 | struct page * page; | |
335 | page = pfn_to_page(zone_pfn + zone->zone_start_pfn); | |
336 | if (PageNosave(page) && PageNosaveFree(page)) { | |
337 | ClearPageNosave(page); | |
338 | ClearPageNosaveFree(page); | |
339 | free_page((long) page_address(page)); | |
340 | } | |
341 | } | |
342 | } | |
343 | } | |
344 | ||
345 | ||
346 | /** | |
347 | * enough_free_mem - Make sure we enough free memory to snapshot. | |
348 | * | |
349 | * Returns TRUE or FALSE after checking the number of available | |
350 | * free pages. | |
351 | */ | |
352 | ||
a0f49651 | 353 | static int enough_free_mem(unsigned nr_pages) |
25761b6e RW |
354 | { |
355 | pr_debug("swsusp: available memory: %u pages\n", nr_free_pages()); | |
a0f49651 RW |
356 | return nr_free_pages() > (nr_pages + PAGES_FOR_IO + |
357 | (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE); | |
25761b6e RW |
358 | } |
359 | ||
360 | ||
a0f49651 | 361 | static struct pbe *swsusp_alloc(unsigned nr_pages) |
25761b6e | 362 | { |
a0f49651 | 363 | struct pbe *pblist, *p; |
25761b6e | 364 | |
a0f49651 | 365 | if (!(pblist = alloc_pagedir(nr_pages))) { |
25761b6e | 366 | printk(KERN_ERR "suspend: Allocating pagedir failed.\n"); |
a0f49651 | 367 | return NULL; |
25761b6e | 368 | } |
a0f49651 | 369 | create_pbe_list(pblist, nr_pages); |
25761b6e | 370 | |
a0f49651 | 371 | for_each_pbe (p, pblist) { |
25761b6e RW |
372 | p->address = (unsigned long)alloc_image_page(); |
373 | if (!p->address) { | |
374 | printk(KERN_ERR "suspend: Allocating image pages failed.\n"); | |
375 | swsusp_free(); | |
a0f49651 | 376 | return NULL; |
25761b6e RW |
377 | } |
378 | } | |
379 | ||
a0f49651 | 380 | return pblist; |
25761b6e RW |
381 | } |
382 | ||
383 | static int suspend_prepare_image(void) | |
384 | { | |
a0f49651 | 385 | unsigned nr_pages; |
25761b6e RW |
386 | |
387 | pr_debug("swsusp: critical section: \n"); | |
388 | if (save_highmem()) { | |
389 | printk(KERN_CRIT "swsusp: Not enough free pages for highmem\n"); | |
390 | restore_highmem(); | |
391 | return -ENOMEM; | |
392 | } | |
393 | ||
394 | drain_local_pages(); | |
a0f49651 RW |
395 | nr_pages = count_data_pages(); |
396 | printk("swsusp: Need to copy %u pages\n", nr_pages); | |
25761b6e RW |
397 | |
398 | pr_debug("swsusp: pages needed: %u + %lu + %u, free: %u\n", | |
a0f49651 RW |
399 | nr_pages, |
400 | (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE, | |
25761b6e RW |
401 | PAGES_FOR_IO, nr_free_pages()); |
402 | ||
a0f49651 RW |
403 | /* This is needed because of the fixed size of swsusp_info */ |
404 | if (MAX_PBES < (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE) | |
405 | return -ENOSPC; | |
406 | ||
407 | if (!enough_free_mem(nr_pages)) { | |
25761b6e RW |
408 | printk(KERN_ERR "swsusp: Not enough free memory\n"); |
409 | return -ENOMEM; | |
410 | } | |
411 | ||
a0f49651 | 412 | if (!enough_swap(nr_pages)) { |
25761b6e RW |
413 | printk(KERN_ERR "swsusp: Not enough free swap\n"); |
414 | return -ENOSPC; | |
415 | } | |
416 | ||
a0f49651 RW |
417 | pagedir_nosave = swsusp_alloc(nr_pages); |
418 | if (!pagedir_nosave) | |
419 | return -ENOMEM; | |
25761b6e RW |
420 | |
421 | /* During allocating of suspend pagedir, new cold pages may appear. | |
422 | * Kill them. | |
423 | */ | |
424 | drain_local_pages(); | |
a0f49651 | 425 | copy_data_pages(pagedir_nosave); |
25761b6e RW |
426 | |
427 | /* | |
428 | * End of critical section. From now on, we can write to memory, | |
429 | * but we should not touch disk. This specially means we must _not_ | |
430 | * touch swap space! Except we must write out our image of course. | |
431 | */ | |
432 | ||
a0f49651 RW |
433 | nr_copy_pages = nr_pages; |
434 | ||
435 | printk("swsusp: critical section/: done (%d pages copied)\n", nr_pages); | |
25761b6e RW |
436 | return 0; |
437 | } | |
438 | ||
439 | ||
440 | asmlinkage int swsusp_save(void) | |
441 | { | |
442 | return suspend_prepare_image(); | |
443 | } |