Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/kernel/power/swsusp.c | |
3 | * | |
4 | * This file is to realize architecture-independent | |
5 | * machine suspend feature using pretty near only high-level routines | |
6 | * | |
7 | * Copyright (C) 1998-2001 Gabor Kuti <seasons@fornax.hu> | |
8 | * Copyright (C) 1998,2001-2004 Pavel Machek <pavel@suse.cz> | |
9 | * | |
10 | * This file is released under the GPLv2. | |
11 | * | |
12 | * I'd like to thank the following people for their work: | |
2e4d5822 | 13 | * |
1da177e4 LT |
14 | * Pavel Machek <pavel@ucw.cz>: |
15 | * Modifications, defectiveness pointing, being with me at the very beginning, | |
16 | * suspend to swap space, stop all tasks. Port to 2.4.18-ac and 2.5.17. | |
17 | * | |
2e4d5822 | 18 | * Steve Doddi <dirk@loth.demon.co.uk>: |
1da177e4 LT |
19 | * Support the possibility of hardware state restoring. |
20 | * | |
21 | * Raph <grey.havens@earthling.net>: | |
22 | * Support for preserving states of network devices and virtual console | |
23 | * (including X and svgatextmode) | |
24 | * | |
25 | * Kurt Garloff <garloff@suse.de>: | |
26 | * Straightened the critical function in order to prevent compilers from | |
27 | * playing tricks with local variables. | |
28 | * | |
29 | * Andreas Mohr <a.mohr@mailto.de> | |
30 | * | |
31 | * Alex Badea <vampire@go.ro>: | |
32 | * Fixed runaway init | |
33 | * | |
34 | * More state savers are welcome. Especially for the scsi layer... | |
35 | * | |
36 | * For TODOs,FIXMEs also look in Documentation/power/swsusp.txt | |
37 | */ | |
38 | ||
39 | #include <linux/module.h> | |
40 | #include <linux/mm.h> | |
41 | #include <linux/suspend.h> | |
42 | #include <linux/smp_lock.h> | |
43 | #include <linux/file.h> | |
44 | #include <linux/utsname.h> | |
45 | #include <linux/version.h> | |
46 | #include <linux/delay.h> | |
47 | #include <linux/reboot.h> | |
48 | #include <linux/bitops.h> | |
49 | #include <linux/vt_kern.h> | |
50 | #include <linux/kbd_kern.h> | |
51 | #include <linux/keyboard.h> | |
52 | #include <linux/spinlock.h> | |
53 | #include <linux/genhd.h> | |
54 | #include <linux/kernel.h> | |
55 | #include <linux/major.h> | |
56 | #include <linux/swap.h> | |
57 | #include <linux/pm.h> | |
58 | #include <linux/device.h> | |
59 | #include <linux/buffer_head.h> | |
60 | #include <linux/swapops.h> | |
61 | #include <linux/bootmem.h> | |
62 | #include <linux/syscalls.h> | |
63 | #include <linux/console.h> | |
64 | #include <linux/highmem.h> | |
65 | #include <linux/bio.h> | |
d53d9f16 | 66 | #include <linux/mount.h> |
1da177e4 LT |
67 | |
68 | #include <asm/uaccess.h> | |
69 | #include <asm/mmu_context.h> | |
70 | #include <asm/pgtable.h> | |
71 | #include <asm/tlbflush.h> | |
72 | #include <asm/io.h> | |
73 | ||
74 | #include "power.h" | |
75 | ||
76 | /* References to section boundaries */ | |
77 | extern const void __nosave_begin, __nosave_end; | |
78 | ||
79 | /* Variables to be preserved over suspend */ | |
80 | static int nr_copy_pages_check; | |
81 | ||
82 | extern char resume_file[]; | |
83 | ||
84 | /* Local variables that should not be affected by save */ | |
52c1da39 | 85 | static unsigned int nr_copy_pages __nosavedata = 0; |
1da177e4 LT |
86 | |
87 | /* Suspend pagedir is allocated before final copy, therefore it | |
2e4d5822 | 88 | must be freed after resume |
1da177e4 LT |
89 | |
90 | Warning: this is evil. There are actually two pagedirs at time of | |
91 | resume. One is "pagedir_save", which is empty frame allocated at | |
2e4d5822 | 92 | time of suspend, that must be freed. Second is "pagedir_nosave", |
1da177e4 LT |
93 | allocated at time of resume, that travels through memory not to |
94 | collide with anything. | |
95 | ||
96 | Warning: this is even more evil than it seems. Pagedirs this file | |
97 | talks about are completely different from page directories used by | |
98 | MMU hardware. | |
99 | */ | |
100 | suspend_pagedir_t *pagedir_nosave __nosavedata = NULL; | |
101 | static suspend_pagedir_t *pagedir_save; | |
102 | ||
103 | #define SWSUSP_SIG "S1SUSPEND" | |
104 | ||
105 | static struct swsusp_header { | |
106 | char reserved[PAGE_SIZE - 20 - sizeof(swp_entry_t)]; | |
107 | swp_entry_t swsusp_info; | |
108 | char orig_sig[10]; | |
109 | char sig[10]; | |
110 | } __attribute__((packed, aligned(PAGE_SIZE))) swsusp_header; | |
111 | ||
112 | static struct swsusp_info swsusp_info; | |
113 | ||
114 | /* | |
115 | * XXX: We try to keep some more pages free so that I/O operations succeed | |
116 | * without paging. Might this be more? | |
117 | */ | |
118 | #define PAGES_FOR_IO 512 | |
119 | ||
120 | /* | |
121 | * Saving part... | |
122 | */ | |
123 | ||
124 | /* We memorize in swapfile_used what swap devices are used for suspension */ | |
125 | #define SWAPFILE_UNUSED 0 | |
126 | #define SWAPFILE_SUSPEND 1 /* This is the suspending device */ | |
127 | #define SWAPFILE_IGNORED 2 /* Those are other swap devices ignored for suspension */ | |
128 | ||
129 | static unsigned short swapfile_used[MAX_SWAPFILES]; | |
130 | static unsigned short root_swap; | |
131 | ||
132 | static int mark_swapfiles(swp_entry_t prev) | |
133 | { | |
134 | int error; | |
135 | ||
2e4d5822 | 136 | rw_swap_page_sync(READ, |
1da177e4 LT |
137 | swp_entry(root_swap, 0), |
138 | virt_to_page((unsigned long)&swsusp_header)); | |
139 | if (!memcmp("SWAP-SPACE",swsusp_header.sig, 10) || | |
140 | !memcmp("SWAPSPACE2",swsusp_header.sig, 10)) { | |
141 | memcpy(swsusp_header.orig_sig,swsusp_header.sig, 10); | |
142 | memcpy(swsusp_header.sig,SWSUSP_SIG, 10); | |
143 | swsusp_header.swsusp_info = prev; | |
2e4d5822 | 144 | error = rw_swap_page_sync(WRITE, |
1da177e4 LT |
145 | swp_entry(root_swap, 0), |
146 | virt_to_page((unsigned long) | |
147 | &swsusp_header)); | |
148 | } else { | |
149 | pr_debug("swsusp: Partition is not swap space.\n"); | |
150 | error = -ENODEV; | |
151 | } | |
152 | return error; | |
153 | } | |
154 | ||
155 | /* | |
156 | * Check whether the swap device is the specified resume | |
157 | * device, irrespective of whether they are specified by | |
158 | * identical names. | |
159 | * | |
160 | * (Thus, device inode aliasing is allowed. You can say /dev/hda4 | |
161 | * instead of /dev/ide/host0/bus0/target0/lun0/part4 [if using devfs] | |
162 | * and they'll be considered the same device. This is *necessary* for | |
163 | * devfs, since the resume code can only recognize the form /dev/hda4, | |
164 | * but the suspend code would see the long name.) | |
165 | */ | |
166 | static int is_resume_device(const struct swap_info_struct *swap_info) | |
167 | { | |
168 | struct file *file = swap_info->swap_file; | |
169 | struct inode *inode = file->f_dentry->d_inode; | |
170 | ||
171 | return S_ISBLK(inode->i_mode) && | |
172 | swsusp_resume_device == MKDEV(imajor(inode), iminor(inode)); | |
173 | } | |
174 | ||
175 | static int swsusp_swap_check(void) /* This is called before saving image */ | |
176 | { | |
177 | int i, len; | |
2e4d5822 | 178 | |
1da177e4 LT |
179 | len=strlen(resume_file); |
180 | root_swap = 0xFFFF; | |
2e4d5822 | 181 | |
1da177e4 | 182 | swap_list_lock(); |
2e4d5822 | 183 | for (i=0; i<MAX_SWAPFILES; i++) { |
1da177e4 LT |
184 | if (swap_info[i].flags == 0) { |
185 | swapfile_used[i]=SWAPFILE_UNUSED; | |
186 | } else { | |
2e4d5822 | 187 | if (!len) { |
1da177e4 | 188 | printk(KERN_WARNING "resume= option should be used to set suspend device" ); |
2e4d5822 | 189 | if (root_swap == 0xFFFF) { |
1da177e4 LT |
190 | swapfile_used[i] = SWAPFILE_SUSPEND; |
191 | root_swap = i; | |
192 | } else | |
2e4d5822 | 193 | swapfile_used[i] = SWAPFILE_IGNORED; |
1da177e4 LT |
194 | } else { |
195 | /* we ignore all swap devices that are not the resume_file */ | |
196 | if (is_resume_device(&swap_info[i])) { | |
197 | swapfile_used[i] = SWAPFILE_SUSPEND; | |
198 | root_swap = i; | |
199 | } else { | |
200 | swapfile_used[i] = SWAPFILE_IGNORED; | |
201 | } | |
202 | } | |
203 | } | |
204 | } | |
205 | swap_list_unlock(); | |
206 | return (root_swap != 0xffff) ? 0 : -ENODEV; | |
207 | } | |
208 | ||
209 | /** | |
210 | * This is called after saving image so modification | |
211 | * will be lost after resume... and that's what we want. | |
212 | * we make the device unusable. A new call to | |
2e4d5822 | 213 | * lock_swapdevices can unlock the devices. |
1da177e4 LT |
214 | */ |
215 | static void lock_swapdevices(void) | |
216 | { | |
217 | int i; | |
218 | ||
219 | swap_list_lock(); | |
2e4d5822 PM |
220 | for (i = 0; i< MAX_SWAPFILES; i++) |
221 | if (swapfile_used[i] == SWAPFILE_IGNORED) { | |
1da177e4 LT |
222 | swap_info[i].flags ^= 0xFF; |
223 | } | |
224 | swap_list_unlock(); | |
225 | } | |
226 | ||
227 | /** | |
228 | * write_swap_page - Write one page to a fresh swap location. | |
229 | * @addr: Address we're writing. | |
230 | * @loc: Place to store the entry we used. | |
231 | * | |
232 | * Allocate a new swap entry and 'sync' it. Note we discard -EIO | |
2e4d5822 | 233 | * errors. That is an artifact left over from swsusp. It did not |
1da177e4 LT |
234 | * check the return of rw_swap_page_sync() at all, since most pages |
235 | * written back to swap would return -EIO. | |
236 | * This is a partial improvement, since we will at least return other | |
237 | * errors, though we need to eventually fix the damn code. | |
238 | */ | |
239 | static int write_page(unsigned long addr, swp_entry_t * loc) | |
240 | { | |
241 | swp_entry_t entry; | |
242 | int error = 0; | |
243 | ||
244 | entry = get_swap_page(); | |
2e4d5822 | 245 | if (swp_offset(entry) && |
1da177e4 LT |
246 | swapfile_used[swp_type(entry)] == SWAPFILE_SUSPEND) { |
247 | error = rw_swap_page_sync(WRITE, entry, | |
248 | virt_to_page(addr)); | |
249 | if (error == -EIO) | |
250 | error = 0; | |
251 | if (!error) | |
252 | *loc = entry; | |
253 | } else | |
254 | error = -ENOSPC; | |
255 | return error; | |
256 | } | |
257 | ||
258 | /** | |
259 | * data_free - Free the swap entries used by the saved image. | |
260 | * | |
2e4d5822 | 261 | * Walk the list of used swap entries and free each one. |
1da177e4 LT |
262 | * This is only used for cleanup when suspend fails. |
263 | */ | |
264 | static void data_free(void) | |
265 | { | |
266 | swp_entry_t entry; | |
267 | int i; | |
268 | ||
269 | for (i = 0; i < nr_copy_pages; i++) { | |
270 | entry = (pagedir_nosave + i)->swap_address; | |
271 | if (entry.val) | |
272 | swap_free(entry); | |
273 | else | |
274 | break; | |
275 | (pagedir_nosave + i)->swap_address = (swp_entry_t){0}; | |
276 | } | |
277 | } | |
278 | ||
279 | /** | |
280 | * data_write - Write saved image to swap. | |
281 | * | |
282 | * Walk the list of pages in the image and sync each one to swap. | |
283 | */ | |
284 | static int data_write(void) | |
285 | { | |
286 | int error = 0, i = 0; | |
287 | unsigned int mod = nr_copy_pages / 100; | |
288 | struct pbe *p; | |
289 | ||
290 | if (!mod) | |
291 | mod = 1; | |
292 | ||
293 | printk( "Writing data to swap (%d pages)... ", nr_copy_pages ); | |
2e4d5822 | 294 | for_each_pbe (p, pagedir_nosave) { |
1da177e4 LT |
295 | if (!(i%mod)) |
296 | printk( "\b\b\b\b%3d%%", i / mod ); | |
297 | if ((error = write_page(p->address, &(p->swap_address)))) | |
298 | return error; | |
299 | i++; | |
300 | } | |
301 | printk("\b\b\b\bdone\n"); | |
302 | return error; | |
303 | } | |
304 | ||
305 | static void dump_info(void) | |
306 | { | |
307 | pr_debug(" swsusp: Version: %u\n",swsusp_info.version_code); | |
308 | pr_debug(" swsusp: Num Pages: %ld\n",swsusp_info.num_physpages); | |
309 | pr_debug(" swsusp: UTS Sys: %s\n",swsusp_info.uts.sysname); | |
310 | pr_debug(" swsusp: UTS Node: %s\n",swsusp_info.uts.nodename); | |
311 | pr_debug(" swsusp: UTS Release: %s\n",swsusp_info.uts.release); | |
312 | pr_debug(" swsusp: UTS Version: %s\n",swsusp_info.uts.version); | |
313 | pr_debug(" swsusp: UTS Machine: %s\n",swsusp_info.uts.machine); | |
314 | pr_debug(" swsusp: UTS Domain: %s\n",swsusp_info.uts.domainname); | |
315 | pr_debug(" swsusp: CPUs: %d\n",swsusp_info.cpus); | |
316 | pr_debug(" swsusp: Image: %ld Pages\n",swsusp_info.image_pages); | |
317 | pr_debug(" swsusp: Pagedir: %ld Pages\n",swsusp_info.pagedir_pages); | |
318 | } | |
319 | ||
320 | static void init_header(void) | |
321 | { | |
322 | memset(&swsusp_info, 0, sizeof(swsusp_info)); | |
323 | swsusp_info.version_code = LINUX_VERSION_CODE; | |
324 | swsusp_info.num_physpages = num_physpages; | |
325 | memcpy(&swsusp_info.uts, &system_utsname, sizeof(system_utsname)); | |
326 | ||
327 | swsusp_info.suspend_pagedir = pagedir_nosave; | |
328 | swsusp_info.cpus = num_online_cpus(); | |
329 | swsusp_info.image_pages = nr_copy_pages; | |
330 | } | |
331 | ||
332 | static int close_swap(void) | |
333 | { | |
334 | swp_entry_t entry; | |
335 | int error; | |
336 | ||
337 | dump_info(); | |
338 | error = write_page((unsigned long)&swsusp_info, &entry); | |
2e4d5822 | 339 | if (!error) { |
1da177e4 LT |
340 | printk( "S" ); |
341 | error = mark_swapfiles(entry); | |
342 | printk( "|\n" ); | |
343 | } | |
344 | return error; | |
345 | } | |
346 | ||
347 | /** | |
348 | * free_pagedir_entries - Free pages used by the page directory. | |
349 | * | |
350 | * This is used during suspend for error recovery. | |
351 | */ | |
352 | ||
353 | static void free_pagedir_entries(void) | |
354 | { | |
355 | int i; | |
356 | ||
357 | for (i = 0; i < swsusp_info.pagedir_pages; i++) | |
358 | swap_free(swsusp_info.pagedir[i]); | |
359 | } | |
360 | ||
361 | ||
362 | /** | |
363 | * write_pagedir - Write the array of pages holding the page directory. | |
364 | * @last: Last swap entry we write (needed for header). | |
365 | */ | |
366 | ||
367 | static int write_pagedir(void) | |
368 | { | |
369 | int error = 0; | |
370 | unsigned n = 0; | |
371 | struct pbe * pbe; | |
372 | ||
373 | printk( "Writing pagedir..."); | |
2e4d5822 | 374 | for_each_pb_page (pbe, pagedir_nosave) { |
1da177e4 LT |
375 | if ((error = write_page((unsigned long)pbe, &swsusp_info.pagedir[n++]))) |
376 | return error; | |
377 | } | |
378 | ||
379 | swsusp_info.pagedir_pages = n; | |
380 | printk("done (%u pages)\n", n); | |
381 | return error; | |
382 | } | |
383 | ||
384 | /** | |
385 | * write_suspend_image - Write entire image and metadata. | |
386 | * | |
387 | */ | |
388 | ||
389 | static int write_suspend_image(void) | |
390 | { | |
391 | int error; | |
392 | ||
393 | init_header(); | |
394 | if ((error = data_write())) | |
395 | goto FreeData; | |
396 | ||
397 | if ((error = write_pagedir())) | |
398 | goto FreePagedir; | |
399 | ||
400 | if ((error = close_swap())) | |
401 | goto FreePagedir; | |
402 | Done: | |
403 | return error; | |
404 | FreePagedir: | |
405 | free_pagedir_entries(); | |
406 | FreeData: | |
407 | data_free(); | |
408 | goto Done; | |
409 | } | |
410 | ||
411 | ||
412 | #ifdef CONFIG_HIGHMEM | |
413 | struct highmem_page { | |
414 | char *data; | |
415 | struct page *page; | |
416 | struct highmem_page *next; | |
417 | }; | |
418 | ||
419 | static struct highmem_page *highmem_copy; | |
420 | ||
421 | static int save_highmem_zone(struct zone *zone) | |
422 | { | |
423 | unsigned long zone_pfn; | |
424 | mark_free_pages(zone); | |
425 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) { | |
426 | struct page *page; | |
427 | struct highmem_page *save; | |
428 | void *kaddr; | |
429 | unsigned long pfn = zone_pfn + zone->zone_start_pfn; | |
430 | ||
431 | if (!(pfn%1000)) | |
432 | printk("."); | |
433 | if (!pfn_valid(pfn)) | |
434 | continue; | |
435 | page = pfn_to_page(pfn); | |
436 | /* | |
437 | * This condition results from rvmalloc() sans vmalloc_32() | |
438 | * and architectural memory reservations. This should be | |
439 | * corrected eventually when the cases giving rise to this | |
440 | * are better understood. | |
441 | */ | |
442 | if (PageReserved(page)) { | |
443 | printk("highmem reserved page?!\n"); | |
444 | continue; | |
445 | } | |
446 | BUG_ON(PageNosave(page)); | |
447 | if (PageNosaveFree(page)) | |
448 | continue; | |
449 | save = kmalloc(sizeof(struct highmem_page), GFP_ATOMIC); | |
450 | if (!save) | |
451 | return -ENOMEM; | |
452 | save->next = highmem_copy; | |
453 | save->page = page; | |
454 | save->data = (void *) get_zeroed_page(GFP_ATOMIC); | |
455 | if (!save->data) { | |
456 | kfree(save); | |
457 | return -ENOMEM; | |
458 | } | |
459 | kaddr = kmap_atomic(page, KM_USER0); | |
460 | memcpy(save->data, kaddr, PAGE_SIZE); | |
461 | kunmap_atomic(kaddr, KM_USER0); | |
462 | highmem_copy = save; | |
463 | } | |
464 | return 0; | |
465 | } | |
466 | #endif /* CONFIG_HIGHMEM */ | |
467 | ||
468 | ||
469 | static int save_highmem(void) | |
470 | { | |
471 | #ifdef CONFIG_HIGHMEM | |
472 | struct zone *zone; | |
473 | int res = 0; | |
474 | ||
475 | pr_debug("swsusp: Saving Highmem\n"); | |
2e4d5822 | 476 | for_each_zone (zone) { |
1da177e4 LT |
477 | if (is_highmem(zone)) |
478 | res = save_highmem_zone(zone); | |
479 | if (res) | |
480 | return res; | |
481 | } | |
482 | #endif | |
483 | return 0; | |
484 | } | |
485 | ||
486 | static int restore_highmem(void) | |
487 | { | |
488 | #ifdef CONFIG_HIGHMEM | |
489 | printk("swsusp: Restoring Highmem\n"); | |
490 | while (highmem_copy) { | |
491 | struct highmem_page *save = highmem_copy; | |
492 | void *kaddr; | |
493 | highmem_copy = save->next; | |
494 | ||
495 | kaddr = kmap_atomic(save->page, KM_USER0); | |
496 | memcpy(kaddr, save->data, PAGE_SIZE); | |
497 | kunmap_atomic(kaddr, KM_USER0); | |
498 | free_page((long) save->data); | |
499 | kfree(save); | |
500 | } | |
501 | #endif | |
502 | return 0; | |
503 | } | |
504 | ||
505 | ||
506 | static int pfn_is_nosave(unsigned long pfn) | |
507 | { | |
508 | unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT; | |
509 | unsigned long nosave_end_pfn = PAGE_ALIGN(__pa(&__nosave_end)) >> PAGE_SHIFT; | |
510 | return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn); | |
511 | } | |
512 | ||
513 | /** | |
514 | * saveable - Determine whether a page should be cloned or not. | |
515 | * @pfn: The page | |
516 | * | |
517 | * We save a page if it's Reserved, and not in the range of pages | |
518 | * statically defined as 'unsaveable', or if it isn't reserved, and | |
519 | * isn't part of a free chunk of pages. | |
520 | */ | |
521 | ||
522 | static int saveable(struct zone * zone, unsigned long * zone_pfn) | |
523 | { | |
524 | unsigned long pfn = *zone_pfn + zone->zone_start_pfn; | |
525 | struct page * page; | |
526 | ||
527 | if (!pfn_valid(pfn)) | |
528 | return 0; | |
529 | ||
530 | page = pfn_to_page(pfn); | |
531 | BUG_ON(PageReserved(page) && PageNosave(page)); | |
532 | if (PageNosave(page)) | |
533 | return 0; | |
534 | if (PageReserved(page) && pfn_is_nosave(pfn)) { | |
535 | pr_debug("[nosave pfn 0x%lx]", pfn); | |
536 | return 0; | |
537 | } | |
538 | if (PageNosaveFree(page)) | |
539 | return 0; | |
540 | ||
541 | return 1; | |
542 | } | |
543 | ||
544 | static void count_data_pages(void) | |
545 | { | |
546 | struct zone *zone; | |
547 | unsigned long zone_pfn; | |
548 | ||
549 | nr_copy_pages = 0; | |
550 | ||
2e4d5822 | 551 | for_each_zone (zone) { |
1da177e4 LT |
552 | if (is_highmem(zone)) |
553 | continue; | |
554 | mark_free_pages(zone); | |
555 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) | |
556 | nr_copy_pages += saveable(zone, &zone_pfn); | |
557 | } | |
558 | } | |
559 | ||
560 | ||
561 | static void copy_data_pages(void) | |
562 | { | |
563 | struct zone *zone; | |
564 | unsigned long zone_pfn; | |
565 | struct pbe * pbe = pagedir_nosave; | |
2e4d5822 | 566 | |
1da177e4 | 567 | pr_debug("copy_data_pages(): pages to copy: %d\n", nr_copy_pages); |
2e4d5822 | 568 | for_each_zone (zone) { |
1da177e4 LT |
569 | if (is_highmem(zone)) |
570 | continue; | |
571 | mark_free_pages(zone); | |
572 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) { | |
573 | if (saveable(zone, &zone_pfn)) { | |
574 | struct page * page; | |
575 | page = pfn_to_page(zone_pfn + zone->zone_start_pfn); | |
576 | BUG_ON(!pbe); | |
577 | pbe->orig_address = (long) page_address(page); | |
578 | /* copy_page is not usable for copying task structs. */ | |
579 | memcpy((void *)pbe->address, (void *)pbe->orig_address, PAGE_SIZE); | |
580 | pbe = pbe->next; | |
581 | } | |
582 | } | |
583 | } | |
584 | BUG_ON(pbe); | |
585 | } | |
586 | ||
587 | ||
588 | /** | |
589 | * calc_nr - Determine the number of pages needed for a pbe list. | |
590 | */ | |
591 | ||
592 | static int calc_nr(int nr_copy) | |
593 | { | |
594 | int extra = 0; | |
595 | int mod = !!(nr_copy % PBES_PER_PAGE); | |
596 | int diff = (nr_copy / PBES_PER_PAGE) + mod; | |
597 | ||
598 | do { | |
599 | extra += diff; | |
600 | nr_copy += diff; | |
601 | mod = !!(nr_copy % PBES_PER_PAGE); | |
602 | diff = (nr_copy / PBES_PER_PAGE) + mod - extra; | |
603 | } while (diff > 0); | |
604 | ||
605 | return nr_copy; | |
606 | } | |
607 | ||
608 | /** | |
609 | * free_pagedir - free pages allocated with alloc_pagedir() | |
610 | */ | |
611 | ||
612 | static inline void free_pagedir(struct pbe *pblist) | |
613 | { | |
614 | struct pbe *pbe; | |
615 | ||
616 | while (pblist) { | |
617 | pbe = (pblist + PB_PAGE_SKIP)->next; | |
618 | free_page((unsigned long)pblist); | |
619 | pblist = pbe; | |
620 | } | |
621 | } | |
622 | ||
623 | /** | |
624 | * fill_pb_page - Create a list of PBEs on a given memory page | |
625 | */ | |
626 | ||
627 | static inline void fill_pb_page(struct pbe *pbpage) | |
628 | { | |
629 | struct pbe *p; | |
630 | ||
631 | p = pbpage; | |
632 | pbpage += PB_PAGE_SKIP; | |
633 | do | |
634 | p->next = p + 1; | |
635 | while (++p < pbpage); | |
636 | } | |
637 | ||
638 | /** | |
639 | * create_pbe_list - Create a list of PBEs on top of a given chain | |
640 | * of memory pages allocated with alloc_pagedir() | |
641 | */ | |
642 | ||
643 | static void create_pbe_list(struct pbe *pblist, unsigned nr_pages) | |
644 | { | |
645 | struct pbe *pbpage, *p; | |
646 | unsigned num = PBES_PER_PAGE; | |
647 | ||
648 | for_each_pb_page (pbpage, pblist) { | |
649 | if (num >= nr_pages) | |
650 | break; | |
651 | ||
652 | fill_pb_page(pbpage); | |
653 | num += PBES_PER_PAGE; | |
654 | } | |
655 | if (pbpage) { | |
656 | for (num -= PBES_PER_PAGE - 1, p = pbpage; num < nr_pages; p++, num++) | |
657 | p->next = p + 1; | |
658 | p->next = NULL; | |
659 | } | |
660 | pr_debug("create_pbe_list(): initialized %d PBEs\n", num); | |
661 | } | |
662 | ||
663 | /** | |
664 | * alloc_pagedir - Allocate the page directory. | |
665 | * | |
666 | * First, determine exactly how many pages we need and | |
667 | * allocate them. | |
668 | * | |
669 | * We arrange the pages in a chain: each page is an array of PBES_PER_PAGE | |
670 | * struct pbe elements (pbes) and the last element in the page points | |
671 | * to the next page. | |
672 | * | |
673 | * On each page we set up a list of struct_pbe elements. | |
674 | */ | |
675 | ||
676 | static struct pbe * alloc_pagedir(unsigned nr_pages) | |
677 | { | |
678 | unsigned num; | |
679 | struct pbe *pblist, *pbe; | |
680 | ||
681 | if (!nr_pages) | |
682 | return NULL; | |
683 | ||
684 | pr_debug("alloc_pagedir(): nr_pages = %d\n", nr_pages); | |
685 | pblist = (struct pbe *)get_zeroed_page(GFP_ATOMIC | __GFP_COLD); | |
686 | for (pbe = pblist, num = PBES_PER_PAGE; pbe && num < nr_pages; | |
687 | pbe = pbe->next, num += PBES_PER_PAGE) { | |
688 | pbe += PB_PAGE_SKIP; | |
689 | pbe->next = (struct pbe *)get_zeroed_page(GFP_ATOMIC | __GFP_COLD); | |
690 | } | |
691 | if (!pbe) { /* get_zeroed_page() failed */ | |
692 | free_pagedir(pblist); | |
693 | pblist = NULL; | |
694 | } | |
695 | return pblist; | |
696 | } | |
697 | ||
698 | /** | |
699 | * free_image_pages - Free pages allocated for snapshot | |
700 | */ | |
701 | ||
702 | static void free_image_pages(void) | |
703 | { | |
704 | struct pbe * p; | |
705 | ||
2e4d5822 | 706 | for_each_pbe (p, pagedir_save) { |
1da177e4 LT |
707 | if (p->address) { |
708 | ClearPageNosave(virt_to_page(p->address)); | |
709 | free_page(p->address); | |
710 | p->address = 0; | |
711 | } | |
712 | } | |
713 | } | |
714 | ||
715 | /** | |
716 | * alloc_image_pages - Allocate pages for the snapshot. | |
717 | */ | |
718 | ||
719 | static int alloc_image_pages(void) | |
720 | { | |
721 | struct pbe * p; | |
722 | ||
2e4d5822 | 723 | for_each_pbe (p, pagedir_save) { |
1da177e4 LT |
724 | p->address = get_zeroed_page(GFP_ATOMIC | __GFP_COLD); |
725 | if (!p->address) | |
726 | return -ENOMEM; | |
727 | SetPageNosave(virt_to_page(p->address)); | |
728 | } | |
729 | return 0; | |
730 | } | |
731 | ||
732 | void swsusp_free(void) | |
733 | { | |
734 | BUG_ON(PageNosave(virt_to_page(pagedir_save))); | |
735 | BUG_ON(PageNosaveFree(virt_to_page(pagedir_save))); | |
736 | free_image_pages(); | |
737 | free_pagedir(pagedir_save); | |
738 | } | |
739 | ||
740 | ||
741 | /** | |
742 | * enough_free_mem - Make sure we enough free memory to snapshot. | |
743 | * | |
2e4d5822 | 744 | * Returns TRUE or FALSE after checking the number of available |
1da177e4 LT |
745 | * free pages. |
746 | */ | |
747 | ||
748 | static int enough_free_mem(void) | |
749 | { | |
750 | if (nr_free_pages() < (nr_copy_pages + PAGES_FOR_IO)) { | |
751 | pr_debug("swsusp: Not enough free pages: Have %d\n", | |
752 | nr_free_pages()); | |
753 | return 0; | |
754 | } | |
755 | return 1; | |
756 | } | |
757 | ||
758 | ||
759 | /** | |
760 | * enough_swap - Make sure we have enough swap to save the image. | |
761 | * | |
2e4d5822 | 762 | * Returns TRUE or FALSE after checking the total amount of swap |
1da177e4 LT |
763 | * space avaiable. |
764 | * | |
765 | * FIXME: si_swapinfo(&i) returns all swap devices information. | |
2e4d5822 | 766 | * We should only consider resume_device. |
1da177e4 LT |
767 | */ |
768 | ||
769 | static int enough_swap(void) | |
770 | { | |
771 | struct sysinfo i; | |
772 | ||
773 | si_swapinfo(&i); | |
774 | if (i.freeswap < (nr_copy_pages + PAGES_FOR_IO)) { | |
775 | pr_debug("swsusp: Not enough swap. Need %ld\n",i.freeswap); | |
776 | return 0; | |
777 | } | |
778 | return 1; | |
779 | } | |
780 | ||
781 | static int swsusp_alloc(void) | |
782 | { | |
783 | int error; | |
784 | ||
c61978b3 PM |
785 | pagedir_nosave = NULL; |
786 | nr_copy_pages = calc_nr(nr_copy_pages); | |
787 | ||
1da177e4 LT |
788 | pr_debug("suspend: (pages needed: %d + %d free: %d)\n", |
789 | nr_copy_pages, PAGES_FOR_IO, nr_free_pages()); | |
790 | ||
1da177e4 LT |
791 | if (!enough_free_mem()) |
792 | return -ENOMEM; | |
793 | ||
794 | if (!enough_swap()) | |
795 | return -ENOSPC; | |
796 | ||
1da177e4 LT |
797 | if (!(pagedir_save = alloc_pagedir(nr_copy_pages))) { |
798 | printk(KERN_ERR "suspend: Allocating pagedir failed.\n"); | |
799 | return -ENOMEM; | |
800 | } | |
801 | create_pbe_list(pagedir_save, nr_copy_pages); | |
802 | pagedir_nosave = pagedir_save; | |
803 | if ((error = alloc_image_pages())) { | |
804 | printk(KERN_ERR "suspend: Allocating image pages failed.\n"); | |
805 | swsusp_free(); | |
806 | return error; | |
807 | } | |
808 | ||
809 | nr_copy_pages_check = nr_copy_pages; | |
810 | return 0; | |
811 | } | |
812 | ||
813 | static int suspend_prepare_image(void) | |
814 | { | |
815 | int error; | |
816 | ||
817 | pr_debug("swsusp: critical section: \n"); | |
818 | if (save_highmem()) { | |
819 | printk(KERN_CRIT "Suspend machine: Not enough free pages for highmem\n"); | |
820 | restore_highmem(); | |
821 | return -ENOMEM; | |
822 | } | |
823 | ||
824 | drain_local_pages(); | |
825 | count_data_pages(); | |
826 | printk("swsusp: Need to copy %u pages\n", nr_copy_pages); | |
827 | ||
828 | error = swsusp_alloc(); | |
829 | if (error) | |
830 | return error; | |
2e4d5822 PM |
831 | |
832 | /* During allocating of suspend pagedir, new cold pages may appear. | |
1da177e4 LT |
833 | * Kill them. |
834 | */ | |
835 | drain_local_pages(); | |
836 | copy_data_pages(); | |
837 | ||
838 | /* | |
839 | * End of critical section. From now on, we can write to memory, | |
840 | * but we should not touch disk. This specially means we must _not_ | |
841 | * touch swap space! Except we must write out our image of course. | |
842 | */ | |
843 | ||
844 | printk("swsusp: critical section/: done (%d pages copied)\n", nr_copy_pages ); | |
845 | return 0; | |
846 | } | |
847 | ||
848 | ||
849 | /* It is important _NOT_ to umount filesystems at this point. We want | |
850 | * them synced (in case something goes wrong) but we DO not want to mark | |
851 | * filesystem clean: it is not. (And it does not matter, if we resume | |
852 | * correctly, we'll mark system clean, anyway.) | |
853 | */ | |
854 | int swsusp_write(void) | |
855 | { | |
856 | int error; | |
857 | device_resume(); | |
858 | lock_swapdevices(); | |
859 | error = write_suspend_image(); | |
860 | /* This will unlock ignored swap devices since writing is finished */ | |
861 | lock_swapdevices(); | |
862 | return error; | |
863 | ||
864 | } | |
865 | ||
866 | ||
867 | extern asmlinkage int swsusp_arch_suspend(void); | |
868 | extern asmlinkage int swsusp_arch_resume(void); | |
869 | ||
870 | ||
871 | asmlinkage int swsusp_save(void) | |
872 | { | |
1da177e4 LT |
873 | return suspend_prepare_image(); |
874 | } | |
875 | ||
876 | int swsusp_suspend(void) | |
877 | { | |
878 | int error; | |
879 | if ((error = arch_prepare_suspend())) | |
880 | return error; | |
881 | local_irq_disable(); | |
882 | /* At this point, device_suspend() has been called, but *not* | |
883 | * device_power_down(). We *must* device_power_down() now. | |
884 | * Otherwise, drivers for some devices (e.g. interrupt controllers) | |
885 | * become desynchronized with the actual state of the hardware | |
886 | * at resume time, and evil weirdness ensues. | |
887 | */ | |
888 | if ((error = device_power_down(PMSG_FREEZE))) { | |
1da177e4 | 889 | local_irq_enable(); |
1da177e4 LT |
890 | return error; |
891 | } | |
47b724f3 PM |
892 | |
893 | if ((error = swsusp_swap_check())) { | |
894 | printk(KERN_ERR "swsusp: FATAL: cannot find swap device, try " | |
895 | "swapon -a!\n"); | |
896 | local_irq_enable(); | |
897 | return error; | |
898 | } | |
899 | ||
1da177e4 LT |
900 | save_processor_state(); |
901 | if ((error = swsusp_arch_suspend())) | |
47b724f3 | 902 | printk("Error %d suspending\n", error); |
1da177e4 LT |
903 | /* Restore control flow magically appears here */ |
904 | restore_processor_state(); | |
905 | BUG_ON (nr_copy_pages_check != nr_copy_pages); | |
906 | restore_highmem(); | |
907 | device_power_up(); | |
908 | local_irq_enable(); | |
909 | return error; | |
910 | } | |
911 | ||
912 | int swsusp_resume(void) | |
913 | { | |
914 | int error; | |
915 | local_irq_disable(); | |
916 | if (device_power_down(PMSG_FREEZE)) | |
917 | printk(KERN_ERR "Some devices failed to power down, very bad\n"); | |
918 | /* We'll ignore saved state, but this gets preempt count (etc) right */ | |
919 | save_processor_state(); | |
920 | error = swsusp_arch_resume(); | |
921 | /* Code below is only ever reached in case of failure. Otherwise | |
922 | * execution continues at place where swsusp_arch_suspend was called | |
923 | */ | |
924 | BUG_ON(!error); | |
925 | restore_processor_state(); | |
926 | restore_highmem(); | |
927 | device_power_up(); | |
928 | local_irq_enable(); | |
929 | return error; | |
930 | } | |
931 | ||
1da177e4 LT |
932 | /** |
933 | * On resume, for storing the PBE list and the image, | |
934 | * we can only use memory pages that do not conflict with the pages | |
935 | * which had been used before suspend. | |
936 | * | |
937 | * We don't know which pages are usable until we allocate them. | |
938 | * | |
939 | * Allocated but unusable (ie eaten) memory pages are linked together | |
940 | * to create a list, so that we can free them easily | |
941 | * | |
942 | * We could have used a type other than (void *) | |
943 | * for this purpose, but ... | |
944 | */ | |
945 | static void **eaten_memory = NULL; | |
946 | ||
947 | static inline void eat_page(void *page) | |
948 | { | |
949 | void **c; | |
950 | ||
951 | c = eaten_memory; | |
952 | eaten_memory = page; | |
953 | *eaten_memory = c; | |
954 | } | |
955 | ||
956 | static unsigned long get_usable_page(unsigned gfp_mask) | |
957 | { | |
958 | unsigned long m; | |
959 | ||
960 | m = get_zeroed_page(gfp_mask); | |
8f9bdf15 | 961 | while (!PageNosaveFree(virt_to_page(m))) { |
1da177e4 LT |
962 | eat_page((void *)m); |
963 | m = get_zeroed_page(gfp_mask); | |
964 | if (!m) | |
965 | break; | |
966 | } | |
967 | return m; | |
968 | } | |
969 | ||
970 | static void free_eaten_memory(void) | |
971 | { | |
972 | unsigned long m; | |
973 | void **c; | |
974 | int i = 0; | |
975 | ||
976 | c = eaten_memory; | |
977 | while (c) { | |
978 | m = (unsigned long)c; | |
979 | c = *c; | |
980 | free_page(m); | |
981 | i++; | |
982 | } | |
983 | eaten_memory = NULL; | |
984 | pr_debug("swsusp: %d unused pages freed\n", i); | |
985 | } | |
986 | ||
987 | /** | |
988 | * check_pagedir - We ensure here that pages that the PBEs point to | |
989 | * won't collide with pages where we're going to restore from the loaded | |
990 | * pages later | |
991 | */ | |
992 | ||
993 | static int check_pagedir(struct pbe *pblist) | |
994 | { | |
995 | struct pbe *p; | |
996 | ||
997 | /* This is necessary, so that we can free allocated pages | |
998 | * in case of failure | |
999 | */ | |
1000 | for_each_pbe (p, pblist) | |
1001 | p->address = 0UL; | |
1002 | ||
1003 | for_each_pbe (p, pblist) { | |
1004 | p->address = get_usable_page(GFP_ATOMIC); | |
1005 | if (!p->address) | |
1006 | return -ENOMEM; | |
1007 | } | |
1008 | return 0; | |
1009 | } | |
1010 | ||
1011 | /** | |
1012 | * swsusp_pagedir_relocate - It is possible, that some memory pages | |
1013 | * occupied by the list of PBEs collide with pages where we're going to | |
1014 | * restore from the loaded pages later. We relocate them here. | |
1015 | */ | |
1016 | ||
1017 | static struct pbe * swsusp_pagedir_relocate(struct pbe *pblist) | |
1018 | { | |
1019 | struct zone *zone; | |
1020 | unsigned long zone_pfn; | |
1021 | struct pbe *pbpage, *tail, *p; | |
1022 | void *m; | |
1023 | int rel = 0, error = 0; | |
1024 | ||
1025 | if (!pblist) /* a sanity check */ | |
1026 | return NULL; | |
1027 | ||
1028 | pr_debug("swsusp: Relocating pagedir (%lu pages to check)\n", | |
1029 | swsusp_info.pagedir_pages); | |
1030 | ||
1031 | /* Set page flags */ | |
1032 | ||
2e4d5822 | 1033 | for_each_zone (zone) { |
1da177e4 LT |
1034 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) |
1035 | SetPageNosaveFree(pfn_to_page(zone_pfn + | |
1036 | zone->zone_start_pfn)); | |
1037 | } | |
1038 | ||
1039 | /* Clear orig addresses */ | |
1040 | ||
1041 | for_each_pbe (p, pblist) | |
1042 | ClearPageNosaveFree(virt_to_page(p->orig_address)); | |
1043 | ||
1044 | tail = pblist + PB_PAGE_SKIP; | |
1045 | ||
1046 | /* Relocate colliding pages */ | |
1047 | ||
1048 | for_each_pb_page (pbpage, pblist) { | |
8f9bdf15 | 1049 | if (!PageNosaveFree(virt_to_page((unsigned long)pbpage))) { |
1da177e4 LT |
1050 | m = (void *)get_usable_page(GFP_ATOMIC | __GFP_COLD); |
1051 | if (!m) { | |
1052 | error = -ENOMEM; | |
1053 | break; | |
1054 | } | |
1055 | memcpy(m, (void *)pbpage, PAGE_SIZE); | |
1056 | if (pbpage == pblist) | |
1057 | pblist = (struct pbe *)m; | |
1058 | else | |
1059 | tail->next = (struct pbe *)m; | |
1060 | ||
1061 | eat_page((void *)pbpage); | |
1062 | pbpage = (struct pbe *)m; | |
1063 | ||
1064 | /* We have to link the PBEs again */ | |
1065 | ||
1066 | for (p = pbpage; p < pbpage + PB_PAGE_SKIP; p++) | |
1067 | if (p->next) /* needed to save the end */ | |
1068 | p->next = p + 1; | |
1069 | ||
1070 | rel++; | |
1071 | } | |
1072 | tail = pbpage + PB_PAGE_SKIP; | |
1073 | } | |
1074 | ||
1075 | if (error) { | |
1076 | printk("\nswsusp: Out of memory\n\n"); | |
1077 | free_pagedir(pblist); | |
1078 | free_eaten_memory(); | |
1079 | pblist = NULL; | |
1080 | } | |
1081 | else | |
1082 | printk("swsusp: Relocated %d pages\n", rel); | |
1083 | ||
1084 | return pblist; | |
1085 | } | |
1086 | ||
4dc3b16b | 1087 | /* |
1da177e4 LT |
1088 | * Using bio to read from swap. |
1089 | * This code requires a bit more work than just using buffer heads | |
1090 | * but, it is the recommended way for 2.5/2.6. | |
1091 | * The following are to signal the beginning and end of I/O. Bios | |
1092 | * finish asynchronously, while we want them to happen synchronously. | |
1093 | * A simple atomic_t, and a wait loop take care of this problem. | |
1094 | */ | |
1095 | ||
1096 | static atomic_t io_done = ATOMIC_INIT(0); | |
1097 | ||
1098 | static int end_io(struct bio * bio, unsigned int num, int err) | |
1099 | { | |
1100 | if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) | |
1101 | panic("I/O error reading memory image"); | |
1102 | atomic_set(&io_done, 0); | |
1103 | return 0; | |
1104 | } | |
1105 | ||
1106 | static struct block_device * resume_bdev; | |
1107 | ||
1108 | /** | |
1109 | * submit - submit BIO request. | |
1110 | * @rw: READ or WRITE. | |
1111 | * @off physical offset of page. | |
1112 | * @page: page we're reading or writing. | |
1113 | * | |
1114 | * Straight from the textbook - allocate and initialize the bio. | |
1115 | * If we're writing, make sure the page is marked as dirty. | |
1116 | * Then submit it and wait. | |
1117 | */ | |
1118 | ||
1119 | static int submit(int rw, pgoff_t page_off, void * page) | |
1120 | { | |
1121 | int error = 0; | |
1122 | struct bio * bio; | |
1123 | ||
1124 | bio = bio_alloc(GFP_ATOMIC, 1); | |
1125 | if (!bio) | |
1126 | return -ENOMEM; | |
1127 | bio->bi_sector = page_off * (PAGE_SIZE >> 9); | |
1128 | bio_get(bio); | |
1129 | bio->bi_bdev = resume_bdev; | |
1130 | bio->bi_end_io = end_io; | |
1131 | ||
1132 | if (bio_add_page(bio, virt_to_page(page), PAGE_SIZE, 0) < PAGE_SIZE) { | |
1133 | printk("swsusp: ERROR: adding page to bio at %ld\n",page_off); | |
1134 | error = -EFAULT; | |
1135 | goto Done; | |
1136 | } | |
1137 | ||
1138 | if (rw == WRITE) | |
1139 | bio_set_pages_dirty(bio); | |
1140 | ||
1141 | atomic_set(&io_done, 1); | |
1142 | submit_bio(rw | (1 << BIO_RW_SYNC), bio); | |
1143 | while (atomic_read(&io_done)) | |
1144 | yield(); | |
1145 | ||
1146 | Done: | |
1147 | bio_put(bio); | |
1148 | return error; | |
1149 | } | |
1150 | ||
1151 | static int bio_read_page(pgoff_t page_off, void * page) | |
1152 | { | |
1153 | return submit(READ, page_off, page); | |
1154 | } | |
1155 | ||
1156 | static int bio_write_page(pgoff_t page_off, void * page) | |
1157 | { | |
1158 | return submit(WRITE, page_off, page); | |
1159 | } | |
1160 | ||
1161 | /* | |
1162 | * Sanity check if this image makes sense with this kernel/swap context | |
1163 | * I really don't think that it's foolproof but more than nothing.. | |
1164 | */ | |
1165 | ||
1166 | static const char * sanity_check(void) | |
1167 | { | |
1168 | dump_info(); | |
47b724f3 | 1169 | if (swsusp_info.version_code != LINUX_VERSION_CODE) |
1da177e4 | 1170 | return "kernel version"; |
47b724f3 | 1171 | if (swsusp_info.num_physpages != num_physpages) |
1da177e4 LT |
1172 | return "memory size"; |
1173 | if (strcmp(swsusp_info.uts.sysname,system_utsname.sysname)) | |
1174 | return "system type"; | |
1175 | if (strcmp(swsusp_info.uts.release,system_utsname.release)) | |
1176 | return "kernel release"; | |
1177 | if (strcmp(swsusp_info.uts.version,system_utsname.version)) | |
1178 | return "version"; | |
1179 | if (strcmp(swsusp_info.uts.machine,system_utsname.machine)) | |
1180 | return "machine"; | |
5a72e04d | 1181 | #if 0 |
1da177e4 LT |
1182 | if(swsusp_info.cpus != num_online_cpus()) |
1183 | return "number of cpus"; | |
5a72e04d | 1184 | #endif |
1da177e4 LT |
1185 | return NULL; |
1186 | } | |
1187 | ||
1188 | ||
1189 | static int check_header(void) | |
1190 | { | |
1191 | const char * reason = NULL; | |
1192 | int error; | |
1193 | ||
1194 | if ((error = bio_read_page(swp_offset(swsusp_header.swsusp_info), &swsusp_info))) | |
1195 | return error; | |
1196 | ||
1197 | /* Is this same machine? */ | |
1198 | if ((reason = sanity_check())) { | |
1199 | printk(KERN_ERR "swsusp: Resume mismatch: %s\n",reason); | |
1200 | return -EPERM; | |
1201 | } | |
1202 | nr_copy_pages = swsusp_info.image_pages; | |
1203 | return error; | |
1204 | } | |
1205 | ||
1206 | static int check_sig(void) | |
1207 | { | |
1208 | int error; | |
1209 | ||
1210 | memset(&swsusp_header, 0, sizeof(swsusp_header)); | |
1211 | if ((error = bio_read_page(0, &swsusp_header))) | |
1212 | return error; | |
1213 | if (!memcmp(SWSUSP_SIG, swsusp_header.sig, 10)) { | |
1214 | memcpy(swsusp_header.sig, swsusp_header.orig_sig, 10); | |
1215 | ||
1216 | /* | |
1217 | * Reset swap signature now. | |
1218 | */ | |
1219 | error = bio_write_page(0, &swsusp_header); | |
1220 | } else { | |
1221 | printk(KERN_ERR "swsusp: Suspend partition has wrong signature?\n"); | |
1222 | return -EINVAL; | |
1223 | } | |
1224 | if (!error) | |
1225 | pr_debug("swsusp: Signature found, resuming\n"); | |
1226 | return error; | |
1227 | } | |
1228 | ||
1229 | /** | |
1230 | * data_read - Read image pages from swap. | |
1231 | * | |
1232 | * You do not need to check for overlaps, check_pagedir() | |
1233 | * already did that. | |
1234 | */ | |
1235 | ||
1236 | static int data_read(struct pbe *pblist) | |
1237 | { | |
1238 | struct pbe * p; | |
1239 | int error = 0; | |
1240 | int i = 0; | |
1241 | int mod = swsusp_info.image_pages / 100; | |
1242 | ||
1243 | if (!mod) | |
1244 | mod = 1; | |
1245 | ||
1246 | printk("swsusp: Reading image data (%lu pages): ", | |
1247 | swsusp_info.image_pages); | |
1248 | ||
1249 | for_each_pbe (p, pblist) { | |
1250 | if (!(i % mod)) | |
1251 | printk("\b\b\b\b%3d%%", i / mod); | |
1252 | ||
1253 | error = bio_read_page(swp_offset(p->swap_address), | |
1254 | (void *)p->address); | |
1255 | if (error) | |
1256 | return error; | |
1257 | ||
1258 | i++; | |
1259 | } | |
1260 | printk("\b\b\b\bdone\n"); | |
1261 | return error; | |
1262 | } | |
1263 | ||
1da177e4 LT |
1264 | /** |
1265 | * read_pagedir - Read page backup list pages from swap | |
1266 | */ | |
1267 | ||
1268 | static int read_pagedir(struct pbe *pblist) | |
1269 | { | |
1270 | struct pbe *pbpage, *p; | |
1271 | unsigned i = 0; | |
1272 | int error; | |
1273 | ||
1274 | if (!pblist) | |
1275 | return -EFAULT; | |
1276 | ||
1277 | printk("swsusp: Reading pagedir (%lu pages)\n", | |
1278 | swsusp_info.pagedir_pages); | |
1279 | ||
1280 | for_each_pb_page (pbpage, pblist) { | |
1281 | unsigned long offset = swp_offset(swsusp_info.pagedir[i++]); | |
1282 | ||
1283 | error = -EFAULT; | |
1284 | if (offset) { | |
1285 | p = (pbpage + PB_PAGE_SKIP)->next; | |
1286 | error = bio_read_page(offset, (void *)pbpage); | |
1287 | (pbpage + PB_PAGE_SKIP)->next = p; | |
1288 | } | |
1289 | if (error) | |
1290 | break; | |
1291 | } | |
1292 | ||
1293 | if (error) | |
1294 | free_page((unsigned long)pblist); | |
1295 | ||
1296 | BUG_ON(i != swsusp_info.pagedir_pages); | |
1297 | ||
1298 | return error; | |
1299 | } | |
1300 | ||
1301 | ||
1302 | static int check_suspend_image(void) | |
1303 | { | |
1304 | int error = 0; | |
1305 | ||
1306 | if ((error = check_sig())) | |
1307 | return error; | |
1308 | ||
1309 | if ((error = check_header())) | |
1310 | return error; | |
1311 | ||
1312 | return 0; | |
1313 | } | |
1314 | ||
1315 | static int read_suspend_image(void) | |
1316 | { | |
1317 | int error = 0; | |
1318 | struct pbe *p; | |
1319 | ||
1320 | if (!(p = alloc_pagedir(nr_copy_pages))) | |
1321 | return -ENOMEM; | |
1322 | ||
1323 | if ((error = read_pagedir(p))) | |
1324 | return error; | |
1325 | ||
1326 | create_pbe_list(p, nr_copy_pages); | |
1327 | ||
1328 | if (!(pagedir_nosave = swsusp_pagedir_relocate(p))) | |
1329 | return -ENOMEM; | |
1330 | ||
1331 | /* Allocate memory for the image and read the data from swap */ | |
1332 | ||
1333 | error = check_pagedir(pagedir_nosave); | |
1334 | free_eaten_memory(); | |
1335 | if (!error) | |
1336 | error = data_read(pagedir_nosave); | |
1337 | ||
1338 | if (error) { /* We fail cleanly */ | |
1339 | for_each_pbe (p, pagedir_nosave) | |
1340 | if (p->address) { | |
1341 | free_page(p->address); | |
1342 | p->address = 0UL; | |
1343 | } | |
1344 | free_pagedir(pagedir_nosave); | |
1345 | } | |
1346 | return error; | |
1347 | } | |
1348 | ||
1349 | /** | |
1350 | * swsusp_check - Check for saved image in swap | |
1351 | */ | |
1352 | ||
1353 | int swsusp_check(void) | |
1354 | { | |
1355 | int error; | |
1356 | ||
1da177e4 LT |
1357 | resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ); |
1358 | if (!IS_ERR(resume_bdev)) { | |
1359 | set_blocksize(resume_bdev, PAGE_SIZE); | |
1360 | error = check_suspend_image(); | |
1361 | if (error) | |
1362 | blkdev_put(resume_bdev); | |
1363 | } else | |
1364 | error = PTR_ERR(resume_bdev); | |
1365 | ||
1366 | if (!error) | |
1367 | pr_debug("swsusp: resume file found\n"); | |
1368 | else | |
1369 | pr_debug("swsusp: Error %d check for resume file\n", error); | |
1370 | return error; | |
1371 | } | |
1372 | ||
1373 | /** | |
1374 | * swsusp_read - Read saved image from swap. | |
1375 | */ | |
1376 | ||
1377 | int swsusp_read(void) | |
1378 | { | |
1379 | int error; | |
1380 | ||
1381 | if (IS_ERR(resume_bdev)) { | |
1382 | pr_debug("swsusp: block device not initialised\n"); | |
1383 | return PTR_ERR(resume_bdev); | |
1384 | } | |
1385 | ||
1386 | error = read_suspend_image(); | |
1387 | blkdev_put(resume_bdev); | |
1388 | ||
1389 | if (!error) | |
1390 | pr_debug("swsusp: Reading resume file was successful\n"); | |
1391 | else | |
1392 | pr_debug("swsusp: Error %d resuming\n", error); | |
1393 | return error; | |
1394 | } | |
1395 | ||
1396 | /** | |
1397 | * swsusp_close - close swap device. | |
1398 | */ | |
1399 | ||
1400 | void swsusp_close(void) | |
1401 | { | |
1402 | if (IS_ERR(resume_bdev)) { | |
1403 | pr_debug("swsusp: block device not initialised\n"); | |
1404 | return; | |
1405 | } | |
1406 | ||
1407 | blkdev_put(resume_bdev); | |
1408 | } |