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: | |
13 | * | |
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 | * | |
18 | * Steve Doddi <dirk@loth.demon.co.uk>: | |
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> | |
66 | ||
67 | #include <asm/uaccess.h> | |
68 | #include <asm/mmu_context.h> | |
69 | #include <asm/pgtable.h> | |
70 | #include <asm/tlbflush.h> | |
71 | #include <asm/io.h> | |
72 | ||
73 | #include "power.h" | |
74 | ||
75 | /* References to section boundaries */ | |
76 | extern const void __nosave_begin, __nosave_end; | |
77 | ||
78 | /* Variables to be preserved over suspend */ | |
79 | static int nr_copy_pages_check; | |
80 | ||
81 | extern char resume_file[]; | |
82 | ||
83 | /* Local variables that should not be affected by save */ | |
84 | unsigned int nr_copy_pages __nosavedata = 0; | |
85 | ||
86 | /* Suspend pagedir is allocated before final copy, therefore it | |
87 | must be freed after resume | |
88 | ||
89 | Warning: this is evil. There are actually two pagedirs at time of | |
90 | resume. One is "pagedir_save", which is empty frame allocated at | |
91 | time of suspend, that must be freed. Second is "pagedir_nosave", | |
92 | allocated at time of resume, that travels through memory not to | |
93 | collide with anything. | |
94 | ||
95 | Warning: this is even more evil than it seems. Pagedirs this file | |
96 | talks about are completely different from page directories used by | |
97 | MMU hardware. | |
98 | */ | |
99 | suspend_pagedir_t *pagedir_nosave __nosavedata = NULL; | |
100 | static suspend_pagedir_t *pagedir_save; | |
101 | ||
102 | #define SWSUSP_SIG "S1SUSPEND" | |
103 | ||
104 | static struct swsusp_header { | |
105 | char reserved[PAGE_SIZE - 20 - sizeof(swp_entry_t)]; | |
106 | swp_entry_t swsusp_info; | |
107 | char orig_sig[10]; | |
108 | char sig[10]; | |
109 | } __attribute__((packed, aligned(PAGE_SIZE))) swsusp_header; | |
110 | ||
111 | static struct swsusp_info swsusp_info; | |
112 | ||
113 | /* | |
114 | * XXX: We try to keep some more pages free so that I/O operations succeed | |
115 | * without paging. Might this be more? | |
116 | */ | |
117 | #define PAGES_FOR_IO 512 | |
118 | ||
119 | /* | |
120 | * Saving part... | |
121 | */ | |
122 | ||
123 | /* We memorize in swapfile_used what swap devices are used for suspension */ | |
124 | #define SWAPFILE_UNUSED 0 | |
125 | #define SWAPFILE_SUSPEND 1 /* This is the suspending device */ | |
126 | #define SWAPFILE_IGNORED 2 /* Those are other swap devices ignored for suspension */ | |
127 | ||
128 | static unsigned short swapfile_used[MAX_SWAPFILES]; | |
129 | static unsigned short root_swap; | |
130 | ||
131 | static int mark_swapfiles(swp_entry_t prev) | |
132 | { | |
133 | int error; | |
134 | ||
135 | rw_swap_page_sync(READ, | |
136 | swp_entry(root_swap, 0), | |
137 | virt_to_page((unsigned long)&swsusp_header)); | |
138 | if (!memcmp("SWAP-SPACE",swsusp_header.sig, 10) || | |
139 | !memcmp("SWAPSPACE2",swsusp_header.sig, 10)) { | |
140 | memcpy(swsusp_header.orig_sig,swsusp_header.sig, 10); | |
141 | memcpy(swsusp_header.sig,SWSUSP_SIG, 10); | |
142 | swsusp_header.swsusp_info = prev; | |
143 | error = rw_swap_page_sync(WRITE, | |
144 | swp_entry(root_swap, 0), | |
145 | virt_to_page((unsigned long) | |
146 | &swsusp_header)); | |
147 | } else { | |
148 | pr_debug("swsusp: Partition is not swap space.\n"); | |
149 | error = -ENODEV; | |
150 | } | |
151 | return error; | |
152 | } | |
153 | ||
154 | /* | |
155 | * Check whether the swap device is the specified resume | |
156 | * device, irrespective of whether they are specified by | |
157 | * identical names. | |
158 | * | |
159 | * (Thus, device inode aliasing is allowed. You can say /dev/hda4 | |
160 | * instead of /dev/ide/host0/bus0/target0/lun0/part4 [if using devfs] | |
161 | * and they'll be considered the same device. This is *necessary* for | |
162 | * devfs, since the resume code can only recognize the form /dev/hda4, | |
163 | * but the suspend code would see the long name.) | |
164 | */ | |
165 | static int is_resume_device(const struct swap_info_struct *swap_info) | |
166 | { | |
167 | struct file *file = swap_info->swap_file; | |
168 | struct inode *inode = file->f_dentry->d_inode; | |
169 | ||
170 | return S_ISBLK(inode->i_mode) && | |
171 | swsusp_resume_device == MKDEV(imajor(inode), iminor(inode)); | |
172 | } | |
173 | ||
174 | static int swsusp_swap_check(void) /* This is called before saving image */ | |
175 | { | |
176 | int i, len; | |
177 | ||
178 | len=strlen(resume_file); | |
179 | root_swap = 0xFFFF; | |
180 | ||
181 | swap_list_lock(); | |
182 | for(i=0; i<MAX_SWAPFILES; i++) { | |
183 | if (swap_info[i].flags == 0) { | |
184 | swapfile_used[i]=SWAPFILE_UNUSED; | |
185 | } else { | |
186 | if(!len) { | |
187 | printk(KERN_WARNING "resume= option should be used to set suspend device" ); | |
188 | if(root_swap == 0xFFFF) { | |
189 | swapfile_used[i] = SWAPFILE_SUSPEND; | |
190 | root_swap = i; | |
191 | } else | |
192 | swapfile_used[i] = SWAPFILE_IGNORED; | |
193 | } else { | |
194 | /* we ignore all swap devices that are not the resume_file */ | |
195 | if (is_resume_device(&swap_info[i])) { | |
196 | swapfile_used[i] = SWAPFILE_SUSPEND; | |
197 | root_swap = i; | |
198 | } else { | |
199 | swapfile_used[i] = SWAPFILE_IGNORED; | |
200 | } | |
201 | } | |
202 | } | |
203 | } | |
204 | swap_list_unlock(); | |
205 | return (root_swap != 0xffff) ? 0 : -ENODEV; | |
206 | } | |
207 | ||
208 | /** | |
209 | * This is called after saving image so modification | |
210 | * will be lost after resume... and that's what we want. | |
211 | * we make the device unusable. A new call to | |
212 | * lock_swapdevices can unlock the devices. | |
213 | */ | |
214 | static void lock_swapdevices(void) | |
215 | { | |
216 | int i; | |
217 | ||
218 | swap_list_lock(); | |
219 | for(i = 0; i< MAX_SWAPFILES; i++) | |
220 | if(swapfile_used[i] == SWAPFILE_IGNORED) { | |
221 | swap_info[i].flags ^= 0xFF; | |
222 | } | |
223 | swap_list_unlock(); | |
224 | } | |
225 | ||
226 | /** | |
227 | * write_swap_page - Write one page to a fresh swap location. | |
228 | * @addr: Address we're writing. | |
229 | * @loc: Place to store the entry we used. | |
230 | * | |
231 | * Allocate a new swap entry and 'sync' it. Note we discard -EIO | |
232 | * errors. That is an artifact left over from swsusp. It did not | |
233 | * check the return of rw_swap_page_sync() at all, since most pages | |
234 | * written back to swap would return -EIO. | |
235 | * This is a partial improvement, since we will at least return other | |
236 | * errors, though we need to eventually fix the damn code. | |
237 | */ | |
238 | static int write_page(unsigned long addr, swp_entry_t * loc) | |
239 | { | |
240 | swp_entry_t entry; | |
241 | int error = 0; | |
242 | ||
243 | entry = get_swap_page(); | |
244 | if (swp_offset(entry) && | |
245 | swapfile_used[swp_type(entry)] == SWAPFILE_SUSPEND) { | |
246 | error = rw_swap_page_sync(WRITE, entry, | |
247 | virt_to_page(addr)); | |
248 | if (error == -EIO) | |
249 | error = 0; | |
250 | if (!error) | |
251 | *loc = entry; | |
252 | } else | |
253 | error = -ENOSPC; | |
254 | return error; | |
255 | } | |
256 | ||
257 | /** | |
258 | * data_free - Free the swap entries used by the saved image. | |
259 | * | |
260 | * Walk the list of used swap entries and free each one. | |
261 | * This is only used for cleanup when suspend fails. | |
262 | */ | |
263 | static void data_free(void) | |
264 | { | |
265 | swp_entry_t entry; | |
266 | int i; | |
267 | ||
268 | for (i = 0; i < nr_copy_pages; i++) { | |
269 | entry = (pagedir_nosave + i)->swap_address; | |
270 | if (entry.val) | |
271 | swap_free(entry); | |
272 | else | |
273 | break; | |
274 | (pagedir_nosave + i)->swap_address = (swp_entry_t){0}; | |
275 | } | |
276 | } | |
277 | ||
278 | /** | |
279 | * data_write - Write saved image to swap. | |
280 | * | |
281 | * Walk the list of pages in the image and sync each one to swap. | |
282 | */ | |
283 | static int data_write(void) | |
284 | { | |
285 | int error = 0, i = 0; | |
286 | unsigned int mod = nr_copy_pages / 100; | |
287 | struct pbe *p; | |
288 | ||
289 | if (!mod) | |
290 | mod = 1; | |
291 | ||
292 | printk( "Writing data to swap (%d pages)... ", nr_copy_pages ); | |
293 | for_each_pbe(p, pagedir_nosave) { | |
294 | if (!(i%mod)) | |
295 | printk( "\b\b\b\b%3d%%", i / mod ); | |
296 | if ((error = write_page(p->address, &(p->swap_address)))) | |
297 | return error; | |
298 | i++; | |
299 | } | |
300 | printk("\b\b\b\bdone\n"); | |
301 | return error; | |
302 | } | |
303 | ||
304 | static void dump_info(void) | |
305 | { | |
306 | pr_debug(" swsusp: Version: %u\n",swsusp_info.version_code); | |
307 | pr_debug(" swsusp: Num Pages: %ld\n",swsusp_info.num_physpages); | |
308 | pr_debug(" swsusp: UTS Sys: %s\n",swsusp_info.uts.sysname); | |
309 | pr_debug(" swsusp: UTS Node: %s\n",swsusp_info.uts.nodename); | |
310 | pr_debug(" swsusp: UTS Release: %s\n",swsusp_info.uts.release); | |
311 | pr_debug(" swsusp: UTS Version: %s\n",swsusp_info.uts.version); | |
312 | pr_debug(" swsusp: UTS Machine: %s\n",swsusp_info.uts.machine); | |
313 | pr_debug(" swsusp: UTS Domain: %s\n",swsusp_info.uts.domainname); | |
314 | pr_debug(" swsusp: CPUs: %d\n",swsusp_info.cpus); | |
315 | pr_debug(" swsusp: Image: %ld Pages\n",swsusp_info.image_pages); | |
316 | pr_debug(" swsusp: Pagedir: %ld Pages\n",swsusp_info.pagedir_pages); | |
317 | } | |
318 | ||
319 | static void init_header(void) | |
320 | { | |
321 | memset(&swsusp_info, 0, sizeof(swsusp_info)); | |
322 | swsusp_info.version_code = LINUX_VERSION_CODE; | |
323 | swsusp_info.num_physpages = num_physpages; | |
324 | memcpy(&swsusp_info.uts, &system_utsname, sizeof(system_utsname)); | |
325 | ||
326 | swsusp_info.suspend_pagedir = pagedir_nosave; | |
327 | swsusp_info.cpus = num_online_cpus(); | |
328 | swsusp_info.image_pages = nr_copy_pages; | |
329 | } | |
330 | ||
331 | static int close_swap(void) | |
332 | { | |
333 | swp_entry_t entry; | |
334 | int error; | |
335 | ||
336 | dump_info(); | |
337 | error = write_page((unsigned long)&swsusp_info, &entry); | |
338 | if (!error) { | |
339 | printk( "S" ); | |
340 | error = mark_swapfiles(entry); | |
341 | printk( "|\n" ); | |
342 | } | |
343 | return error; | |
344 | } | |
345 | ||
346 | /** | |
347 | * free_pagedir_entries - Free pages used by the page directory. | |
348 | * | |
349 | * This is used during suspend for error recovery. | |
350 | */ | |
351 | ||
352 | static void free_pagedir_entries(void) | |
353 | { | |
354 | int i; | |
355 | ||
356 | for (i = 0; i < swsusp_info.pagedir_pages; i++) | |
357 | swap_free(swsusp_info.pagedir[i]); | |
358 | } | |
359 | ||
360 | ||
361 | /** | |
362 | * write_pagedir - Write the array of pages holding the page directory. | |
363 | * @last: Last swap entry we write (needed for header). | |
364 | */ | |
365 | ||
366 | static int write_pagedir(void) | |
367 | { | |
368 | int error = 0; | |
369 | unsigned n = 0; | |
370 | struct pbe * pbe; | |
371 | ||
372 | printk( "Writing pagedir..."); | |
373 | for_each_pb_page(pbe, pagedir_nosave) { | |
374 | if ((error = write_page((unsigned long)pbe, &swsusp_info.pagedir[n++]))) | |
375 | return error; | |
376 | } | |
377 | ||
378 | swsusp_info.pagedir_pages = n; | |
379 | printk("done (%u pages)\n", n); | |
380 | return error; | |
381 | } | |
382 | ||
383 | /** | |
384 | * write_suspend_image - Write entire image and metadata. | |
385 | * | |
386 | */ | |
387 | ||
388 | static int write_suspend_image(void) | |
389 | { | |
390 | int error; | |
391 | ||
392 | init_header(); | |
393 | if ((error = data_write())) | |
394 | goto FreeData; | |
395 | ||
396 | if ((error = write_pagedir())) | |
397 | goto FreePagedir; | |
398 | ||
399 | if ((error = close_swap())) | |
400 | goto FreePagedir; | |
401 | Done: | |
402 | return error; | |
403 | FreePagedir: | |
404 | free_pagedir_entries(); | |
405 | FreeData: | |
406 | data_free(); | |
407 | goto Done; | |
408 | } | |
409 | ||
410 | ||
411 | #ifdef CONFIG_HIGHMEM | |
412 | struct highmem_page { | |
413 | char *data; | |
414 | struct page *page; | |
415 | struct highmem_page *next; | |
416 | }; | |
417 | ||
418 | static struct highmem_page *highmem_copy; | |
419 | ||
420 | static int save_highmem_zone(struct zone *zone) | |
421 | { | |
422 | unsigned long zone_pfn; | |
423 | mark_free_pages(zone); | |
424 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) { | |
425 | struct page *page; | |
426 | struct highmem_page *save; | |
427 | void *kaddr; | |
428 | unsigned long pfn = zone_pfn + zone->zone_start_pfn; | |
429 | ||
430 | if (!(pfn%1000)) | |
431 | printk("."); | |
432 | if (!pfn_valid(pfn)) | |
433 | continue; | |
434 | page = pfn_to_page(pfn); | |
435 | /* | |
436 | * This condition results from rvmalloc() sans vmalloc_32() | |
437 | * and architectural memory reservations. This should be | |
438 | * corrected eventually when the cases giving rise to this | |
439 | * are better understood. | |
440 | */ | |
441 | if (PageReserved(page)) { | |
442 | printk("highmem reserved page?!\n"); | |
443 | continue; | |
444 | } | |
445 | BUG_ON(PageNosave(page)); | |
446 | if (PageNosaveFree(page)) | |
447 | continue; | |
448 | save = kmalloc(sizeof(struct highmem_page), GFP_ATOMIC); | |
449 | if (!save) | |
450 | return -ENOMEM; | |
451 | save->next = highmem_copy; | |
452 | save->page = page; | |
453 | save->data = (void *) get_zeroed_page(GFP_ATOMIC); | |
454 | if (!save->data) { | |
455 | kfree(save); | |
456 | return -ENOMEM; | |
457 | } | |
458 | kaddr = kmap_atomic(page, KM_USER0); | |
459 | memcpy(save->data, kaddr, PAGE_SIZE); | |
460 | kunmap_atomic(kaddr, KM_USER0); | |
461 | highmem_copy = save; | |
462 | } | |
463 | return 0; | |
464 | } | |
465 | #endif /* CONFIG_HIGHMEM */ | |
466 | ||
467 | ||
468 | static int save_highmem(void) | |
469 | { | |
470 | #ifdef CONFIG_HIGHMEM | |
471 | struct zone *zone; | |
472 | int res = 0; | |
473 | ||
474 | pr_debug("swsusp: Saving Highmem\n"); | |
475 | for_each_zone(zone) { | |
476 | if (is_highmem(zone)) | |
477 | res = save_highmem_zone(zone); | |
478 | if (res) | |
479 | return res; | |
480 | } | |
481 | #endif | |
482 | return 0; | |
483 | } | |
484 | ||
485 | static int restore_highmem(void) | |
486 | { | |
487 | #ifdef CONFIG_HIGHMEM | |
488 | printk("swsusp: Restoring Highmem\n"); | |
489 | while (highmem_copy) { | |
490 | struct highmem_page *save = highmem_copy; | |
491 | void *kaddr; | |
492 | highmem_copy = save->next; | |
493 | ||
494 | kaddr = kmap_atomic(save->page, KM_USER0); | |
495 | memcpy(kaddr, save->data, PAGE_SIZE); | |
496 | kunmap_atomic(kaddr, KM_USER0); | |
497 | free_page((long) save->data); | |
498 | kfree(save); | |
499 | } | |
500 | #endif | |
501 | return 0; | |
502 | } | |
503 | ||
504 | ||
505 | static int pfn_is_nosave(unsigned long pfn) | |
506 | { | |
507 | unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT; | |
508 | unsigned long nosave_end_pfn = PAGE_ALIGN(__pa(&__nosave_end)) >> PAGE_SHIFT; | |
509 | return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn); | |
510 | } | |
511 | ||
512 | /** | |
513 | * saveable - Determine whether a page should be cloned or not. | |
514 | * @pfn: The page | |
515 | * | |
516 | * We save a page if it's Reserved, and not in the range of pages | |
517 | * statically defined as 'unsaveable', or if it isn't reserved, and | |
518 | * isn't part of a free chunk of pages. | |
519 | */ | |
520 | ||
521 | static int saveable(struct zone * zone, unsigned long * zone_pfn) | |
522 | { | |
523 | unsigned long pfn = *zone_pfn + zone->zone_start_pfn; | |
524 | struct page * page; | |
525 | ||
526 | if (!pfn_valid(pfn)) | |
527 | return 0; | |
528 | ||
529 | page = pfn_to_page(pfn); | |
530 | BUG_ON(PageReserved(page) && PageNosave(page)); | |
531 | if (PageNosave(page)) | |
532 | return 0; | |
533 | if (PageReserved(page) && pfn_is_nosave(pfn)) { | |
534 | pr_debug("[nosave pfn 0x%lx]", pfn); | |
535 | return 0; | |
536 | } | |
537 | if (PageNosaveFree(page)) | |
538 | return 0; | |
539 | ||
540 | return 1; | |
541 | } | |
542 | ||
543 | static void count_data_pages(void) | |
544 | { | |
545 | struct zone *zone; | |
546 | unsigned long zone_pfn; | |
547 | ||
548 | nr_copy_pages = 0; | |
549 | ||
550 | for_each_zone(zone) { | |
551 | if (is_highmem(zone)) | |
552 | continue; | |
553 | mark_free_pages(zone); | |
554 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) | |
555 | nr_copy_pages += saveable(zone, &zone_pfn); | |
556 | } | |
557 | } | |
558 | ||
559 | ||
560 | static void copy_data_pages(void) | |
561 | { | |
562 | struct zone *zone; | |
563 | unsigned long zone_pfn; | |
564 | struct pbe * pbe = pagedir_nosave; | |
565 | ||
566 | pr_debug("copy_data_pages(): pages to copy: %d\n", nr_copy_pages); | |
567 | for_each_zone(zone) { | |
568 | if (is_highmem(zone)) | |
569 | continue; | |
570 | mark_free_pages(zone); | |
571 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) { | |
572 | if (saveable(zone, &zone_pfn)) { | |
573 | struct page * page; | |
574 | page = pfn_to_page(zone_pfn + zone->zone_start_pfn); | |
575 | BUG_ON(!pbe); | |
576 | pbe->orig_address = (long) page_address(page); | |
577 | /* copy_page is not usable for copying task structs. */ | |
578 | memcpy((void *)pbe->address, (void *)pbe->orig_address, PAGE_SIZE); | |
579 | pbe = pbe->next; | |
580 | } | |
581 | } | |
582 | } | |
583 | BUG_ON(pbe); | |
584 | } | |
585 | ||
586 | ||
587 | /** | |
588 | * calc_nr - Determine the number of pages needed for a pbe list. | |
589 | */ | |
590 | ||
591 | static int calc_nr(int nr_copy) | |
592 | { | |
593 | int extra = 0; | |
594 | int mod = !!(nr_copy % PBES_PER_PAGE); | |
595 | int diff = (nr_copy / PBES_PER_PAGE) + mod; | |
596 | ||
597 | do { | |
598 | extra += diff; | |
599 | nr_copy += diff; | |
600 | mod = !!(nr_copy % PBES_PER_PAGE); | |
601 | diff = (nr_copy / PBES_PER_PAGE) + mod - extra; | |
602 | } while (diff > 0); | |
603 | ||
604 | return nr_copy; | |
605 | } | |
606 | ||
607 | /** | |
608 | * free_pagedir - free pages allocated with alloc_pagedir() | |
609 | */ | |
610 | ||
611 | static inline void free_pagedir(struct pbe *pblist) | |
612 | { | |
613 | struct pbe *pbe; | |
614 | ||
615 | while (pblist) { | |
616 | pbe = (pblist + PB_PAGE_SKIP)->next; | |
617 | free_page((unsigned long)pblist); | |
618 | pblist = pbe; | |
619 | } | |
620 | } | |
621 | ||
622 | /** | |
623 | * fill_pb_page - Create a list of PBEs on a given memory page | |
624 | */ | |
625 | ||
626 | static inline void fill_pb_page(struct pbe *pbpage) | |
627 | { | |
628 | struct pbe *p; | |
629 | ||
630 | p = pbpage; | |
631 | pbpage += PB_PAGE_SKIP; | |
632 | do | |
633 | p->next = p + 1; | |
634 | while (++p < pbpage); | |
635 | } | |
636 | ||
637 | /** | |
638 | * create_pbe_list - Create a list of PBEs on top of a given chain | |
639 | * of memory pages allocated with alloc_pagedir() | |
640 | */ | |
641 | ||
642 | static void create_pbe_list(struct pbe *pblist, unsigned nr_pages) | |
643 | { | |
644 | struct pbe *pbpage, *p; | |
645 | unsigned num = PBES_PER_PAGE; | |
646 | ||
647 | for_each_pb_page (pbpage, pblist) { | |
648 | if (num >= nr_pages) | |
649 | break; | |
650 | ||
651 | fill_pb_page(pbpage); | |
652 | num += PBES_PER_PAGE; | |
653 | } | |
654 | if (pbpage) { | |
655 | for (num -= PBES_PER_PAGE - 1, p = pbpage; num < nr_pages; p++, num++) | |
656 | p->next = p + 1; | |
657 | p->next = NULL; | |
658 | } | |
659 | pr_debug("create_pbe_list(): initialized %d PBEs\n", num); | |
660 | } | |
661 | ||
662 | /** | |
663 | * alloc_pagedir - Allocate the page directory. | |
664 | * | |
665 | * First, determine exactly how many pages we need and | |
666 | * allocate them. | |
667 | * | |
668 | * We arrange the pages in a chain: each page is an array of PBES_PER_PAGE | |
669 | * struct pbe elements (pbes) and the last element in the page points | |
670 | * to the next page. | |
671 | * | |
672 | * On each page we set up a list of struct_pbe elements. | |
673 | */ | |
674 | ||
675 | static struct pbe * alloc_pagedir(unsigned nr_pages) | |
676 | { | |
677 | unsigned num; | |
678 | struct pbe *pblist, *pbe; | |
679 | ||
680 | if (!nr_pages) | |
681 | return NULL; | |
682 | ||
683 | pr_debug("alloc_pagedir(): nr_pages = %d\n", nr_pages); | |
684 | pblist = (struct pbe *)get_zeroed_page(GFP_ATOMIC | __GFP_COLD); | |
685 | for (pbe = pblist, num = PBES_PER_PAGE; pbe && num < nr_pages; | |
686 | pbe = pbe->next, num += PBES_PER_PAGE) { | |
687 | pbe += PB_PAGE_SKIP; | |
688 | pbe->next = (struct pbe *)get_zeroed_page(GFP_ATOMIC | __GFP_COLD); | |
689 | } | |
690 | if (!pbe) { /* get_zeroed_page() failed */ | |
691 | free_pagedir(pblist); | |
692 | pblist = NULL; | |
693 | } | |
694 | return pblist; | |
695 | } | |
696 | ||
697 | /** | |
698 | * free_image_pages - Free pages allocated for snapshot | |
699 | */ | |
700 | ||
701 | static void free_image_pages(void) | |
702 | { | |
703 | struct pbe * p; | |
704 | ||
705 | for_each_pbe(p, pagedir_save) { | |
706 | if (p->address) { | |
707 | ClearPageNosave(virt_to_page(p->address)); | |
708 | free_page(p->address); | |
709 | p->address = 0; | |
710 | } | |
711 | } | |
712 | } | |
713 | ||
714 | /** | |
715 | * alloc_image_pages - Allocate pages for the snapshot. | |
716 | */ | |
717 | ||
718 | static int alloc_image_pages(void) | |
719 | { | |
720 | struct pbe * p; | |
721 | ||
722 | for_each_pbe(p, pagedir_save) { | |
723 | p->address = get_zeroed_page(GFP_ATOMIC | __GFP_COLD); | |
724 | if (!p->address) | |
725 | return -ENOMEM; | |
726 | SetPageNosave(virt_to_page(p->address)); | |
727 | } | |
728 | return 0; | |
729 | } | |
730 | ||
731 | void swsusp_free(void) | |
732 | { | |
733 | BUG_ON(PageNosave(virt_to_page(pagedir_save))); | |
734 | BUG_ON(PageNosaveFree(virt_to_page(pagedir_save))); | |
735 | free_image_pages(); | |
736 | free_pagedir(pagedir_save); | |
737 | } | |
738 | ||
739 | ||
740 | /** | |
741 | * enough_free_mem - Make sure we enough free memory to snapshot. | |
742 | * | |
743 | * Returns TRUE or FALSE after checking the number of available | |
744 | * free pages. | |
745 | */ | |
746 | ||
747 | static int enough_free_mem(void) | |
748 | { | |
749 | if (nr_free_pages() < (nr_copy_pages + PAGES_FOR_IO)) { | |
750 | pr_debug("swsusp: Not enough free pages: Have %d\n", | |
751 | nr_free_pages()); | |
752 | return 0; | |
753 | } | |
754 | return 1; | |
755 | } | |
756 | ||
757 | ||
758 | /** | |
759 | * enough_swap - Make sure we have enough swap to save the image. | |
760 | * | |
761 | * Returns TRUE or FALSE after checking the total amount of swap | |
762 | * space avaiable. | |
763 | * | |
764 | * FIXME: si_swapinfo(&i) returns all swap devices information. | |
765 | * We should only consider resume_device. | |
766 | */ | |
767 | ||
768 | static int enough_swap(void) | |
769 | { | |
770 | struct sysinfo i; | |
771 | ||
772 | si_swapinfo(&i); | |
773 | if (i.freeswap < (nr_copy_pages + PAGES_FOR_IO)) { | |
774 | pr_debug("swsusp: Not enough swap. Need %ld\n",i.freeswap); | |
775 | return 0; | |
776 | } | |
777 | return 1; | |
778 | } | |
779 | ||
780 | static int swsusp_alloc(void) | |
781 | { | |
782 | int error; | |
783 | ||
784 | pr_debug("suspend: (pages needed: %d + %d free: %d)\n", | |
785 | nr_copy_pages, PAGES_FOR_IO, nr_free_pages()); | |
786 | ||
787 | pagedir_nosave = NULL; | |
788 | if (!enough_free_mem()) | |
789 | return -ENOMEM; | |
790 | ||
791 | if (!enough_swap()) | |
792 | return -ENOSPC; | |
793 | ||
794 | nr_copy_pages = calc_nr(nr_copy_pages); | |
795 | ||
796 | if (!(pagedir_save = alloc_pagedir(nr_copy_pages))) { | |
797 | printk(KERN_ERR "suspend: Allocating pagedir failed.\n"); | |
798 | return -ENOMEM; | |
799 | } | |
800 | create_pbe_list(pagedir_save, nr_copy_pages); | |
801 | pagedir_nosave = pagedir_save; | |
802 | if ((error = alloc_image_pages())) { | |
803 | printk(KERN_ERR "suspend: Allocating image pages failed.\n"); | |
804 | swsusp_free(); | |
805 | return error; | |
806 | } | |
807 | ||
808 | nr_copy_pages_check = nr_copy_pages; | |
809 | return 0; | |
810 | } | |
811 | ||
812 | static int suspend_prepare_image(void) | |
813 | { | |
814 | int error; | |
815 | ||
816 | pr_debug("swsusp: critical section: \n"); | |
817 | if (save_highmem()) { | |
818 | printk(KERN_CRIT "Suspend machine: Not enough free pages for highmem\n"); | |
819 | restore_highmem(); | |
820 | return -ENOMEM; | |
821 | } | |
822 | ||
823 | drain_local_pages(); | |
824 | count_data_pages(); | |
825 | printk("swsusp: Need to copy %u pages\n", nr_copy_pages); | |
826 | ||
827 | error = swsusp_alloc(); | |
828 | if (error) | |
829 | return error; | |
830 | ||
831 | /* During allocating of suspend pagedir, new cold pages may appear. | |
832 | * Kill them. | |
833 | */ | |
834 | drain_local_pages(); | |
835 | copy_data_pages(); | |
836 | ||
837 | /* | |
838 | * End of critical section. From now on, we can write to memory, | |
839 | * but we should not touch disk. This specially means we must _not_ | |
840 | * touch swap space! Except we must write out our image of course. | |
841 | */ | |
842 | ||
843 | printk("swsusp: critical section/: done (%d pages copied)\n", nr_copy_pages ); | |
844 | return 0; | |
845 | } | |
846 | ||
847 | ||
848 | /* It is important _NOT_ to umount filesystems at this point. We want | |
849 | * them synced (in case something goes wrong) but we DO not want to mark | |
850 | * filesystem clean: it is not. (And it does not matter, if we resume | |
851 | * correctly, we'll mark system clean, anyway.) | |
852 | */ | |
853 | int swsusp_write(void) | |
854 | { | |
855 | int error; | |
856 | device_resume(); | |
857 | lock_swapdevices(); | |
858 | error = write_suspend_image(); | |
859 | /* This will unlock ignored swap devices since writing is finished */ | |
860 | lock_swapdevices(); | |
861 | return error; | |
862 | ||
863 | } | |
864 | ||
865 | ||
866 | extern asmlinkage int swsusp_arch_suspend(void); | |
867 | extern asmlinkage int swsusp_arch_resume(void); | |
868 | ||
869 | ||
870 | asmlinkage int swsusp_save(void) | |
871 | { | |
872 | int error = 0; | |
873 | ||
874 | if ((error = swsusp_swap_check())) { | |
875 | printk(KERN_ERR "swsusp: FATAL: cannot find swap device, try " | |
876 | "swapon -a!\n"); | |
877 | return error; | |
878 | } | |
879 | return suspend_prepare_image(); | |
880 | } | |
881 | ||
882 | int swsusp_suspend(void) | |
883 | { | |
884 | int error; | |
885 | if ((error = arch_prepare_suspend())) | |
886 | return error; | |
887 | local_irq_disable(); | |
888 | /* At this point, device_suspend() has been called, but *not* | |
889 | * device_power_down(). We *must* device_power_down() now. | |
890 | * Otherwise, drivers for some devices (e.g. interrupt controllers) | |
891 | * become desynchronized with the actual state of the hardware | |
892 | * at resume time, and evil weirdness ensues. | |
893 | */ | |
894 | if ((error = device_power_down(PMSG_FREEZE))) { | |
895 | printk(KERN_ERR "Some devices failed to power down, aborting suspend\n"); | |
896 | local_irq_enable(); | |
897 | swsusp_free(); | |
898 | return error; | |
899 | } | |
900 | save_processor_state(); | |
901 | if ((error = swsusp_arch_suspend())) | |
902 | swsusp_free(); | |
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 | ||
932 | /* More restore stuff */ | |
933 | ||
934 | /* | |
935 | * Returns true if given address/order collides with any orig_address | |
936 | */ | |
937 | static int does_collide_order(unsigned long addr, int order) | |
938 | { | |
939 | int i; | |
940 | ||
941 | for (i=0; i < (1<<order); i++) | |
942 | if (!PageNosaveFree(virt_to_page(addr + i * PAGE_SIZE))) | |
943 | return 1; | |
944 | return 0; | |
945 | } | |
946 | ||
947 | /** | |
948 | * On resume, for storing the PBE list and the image, | |
949 | * we can only use memory pages that do not conflict with the pages | |
950 | * which had been used before suspend. | |
951 | * | |
952 | * We don't know which pages are usable until we allocate them. | |
953 | * | |
954 | * Allocated but unusable (ie eaten) memory pages are linked together | |
955 | * to create a list, so that we can free them easily | |
956 | * | |
957 | * We could have used a type other than (void *) | |
958 | * for this purpose, but ... | |
959 | */ | |
960 | static void **eaten_memory = NULL; | |
961 | ||
962 | static inline void eat_page(void *page) | |
963 | { | |
964 | void **c; | |
965 | ||
966 | c = eaten_memory; | |
967 | eaten_memory = page; | |
968 | *eaten_memory = c; | |
969 | } | |
970 | ||
971 | static unsigned long get_usable_page(unsigned gfp_mask) | |
972 | { | |
973 | unsigned long m; | |
974 | ||
975 | m = get_zeroed_page(gfp_mask); | |
976 | while (does_collide_order(m, 0)) { | |
977 | eat_page((void *)m); | |
978 | m = get_zeroed_page(gfp_mask); | |
979 | if (!m) | |
980 | break; | |
981 | } | |
982 | return m; | |
983 | } | |
984 | ||
985 | static void free_eaten_memory(void) | |
986 | { | |
987 | unsigned long m; | |
988 | void **c; | |
989 | int i = 0; | |
990 | ||
991 | c = eaten_memory; | |
992 | while (c) { | |
993 | m = (unsigned long)c; | |
994 | c = *c; | |
995 | free_page(m); | |
996 | i++; | |
997 | } | |
998 | eaten_memory = NULL; | |
999 | pr_debug("swsusp: %d unused pages freed\n", i); | |
1000 | } | |
1001 | ||
1002 | /** | |
1003 | * check_pagedir - We ensure here that pages that the PBEs point to | |
1004 | * won't collide with pages where we're going to restore from the loaded | |
1005 | * pages later | |
1006 | */ | |
1007 | ||
1008 | static int check_pagedir(struct pbe *pblist) | |
1009 | { | |
1010 | struct pbe *p; | |
1011 | ||
1012 | /* This is necessary, so that we can free allocated pages | |
1013 | * in case of failure | |
1014 | */ | |
1015 | for_each_pbe (p, pblist) | |
1016 | p->address = 0UL; | |
1017 | ||
1018 | for_each_pbe (p, pblist) { | |
1019 | p->address = get_usable_page(GFP_ATOMIC); | |
1020 | if (!p->address) | |
1021 | return -ENOMEM; | |
1022 | } | |
1023 | return 0; | |
1024 | } | |
1025 | ||
1026 | /** | |
1027 | * swsusp_pagedir_relocate - It is possible, that some memory pages | |
1028 | * occupied by the list of PBEs collide with pages where we're going to | |
1029 | * restore from the loaded pages later. We relocate them here. | |
1030 | */ | |
1031 | ||
1032 | static struct pbe * swsusp_pagedir_relocate(struct pbe *pblist) | |
1033 | { | |
1034 | struct zone *zone; | |
1035 | unsigned long zone_pfn; | |
1036 | struct pbe *pbpage, *tail, *p; | |
1037 | void *m; | |
1038 | int rel = 0, error = 0; | |
1039 | ||
1040 | if (!pblist) /* a sanity check */ | |
1041 | return NULL; | |
1042 | ||
1043 | pr_debug("swsusp: Relocating pagedir (%lu pages to check)\n", | |
1044 | swsusp_info.pagedir_pages); | |
1045 | ||
1046 | /* Set page flags */ | |
1047 | ||
1048 | for_each_zone(zone) { | |
1049 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) | |
1050 | SetPageNosaveFree(pfn_to_page(zone_pfn + | |
1051 | zone->zone_start_pfn)); | |
1052 | } | |
1053 | ||
1054 | /* Clear orig addresses */ | |
1055 | ||
1056 | for_each_pbe (p, pblist) | |
1057 | ClearPageNosaveFree(virt_to_page(p->orig_address)); | |
1058 | ||
1059 | tail = pblist + PB_PAGE_SKIP; | |
1060 | ||
1061 | /* Relocate colliding pages */ | |
1062 | ||
1063 | for_each_pb_page (pbpage, pblist) { | |
1064 | if (does_collide_order((unsigned long)pbpage, 0)) { | |
1065 | m = (void *)get_usable_page(GFP_ATOMIC | __GFP_COLD); | |
1066 | if (!m) { | |
1067 | error = -ENOMEM; | |
1068 | break; | |
1069 | } | |
1070 | memcpy(m, (void *)pbpage, PAGE_SIZE); | |
1071 | if (pbpage == pblist) | |
1072 | pblist = (struct pbe *)m; | |
1073 | else | |
1074 | tail->next = (struct pbe *)m; | |
1075 | ||
1076 | eat_page((void *)pbpage); | |
1077 | pbpage = (struct pbe *)m; | |
1078 | ||
1079 | /* We have to link the PBEs again */ | |
1080 | ||
1081 | for (p = pbpage; p < pbpage + PB_PAGE_SKIP; p++) | |
1082 | if (p->next) /* needed to save the end */ | |
1083 | p->next = p + 1; | |
1084 | ||
1085 | rel++; | |
1086 | } | |
1087 | tail = pbpage + PB_PAGE_SKIP; | |
1088 | } | |
1089 | ||
1090 | if (error) { | |
1091 | printk("\nswsusp: Out of memory\n\n"); | |
1092 | free_pagedir(pblist); | |
1093 | free_eaten_memory(); | |
1094 | pblist = NULL; | |
1095 | } | |
1096 | else | |
1097 | printk("swsusp: Relocated %d pages\n", rel); | |
1098 | ||
1099 | return pblist; | |
1100 | } | |
1101 | ||
1102 | /** | |
1103 | * Using bio to read from swap. | |
1104 | * This code requires a bit more work than just using buffer heads | |
1105 | * but, it is the recommended way for 2.5/2.6. | |
1106 | * The following are to signal the beginning and end of I/O. Bios | |
1107 | * finish asynchronously, while we want them to happen synchronously. | |
1108 | * A simple atomic_t, and a wait loop take care of this problem. | |
1109 | */ | |
1110 | ||
1111 | static atomic_t io_done = ATOMIC_INIT(0); | |
1112 | ||
1113 | static int end_io(struct bio * bio, unsigned int num, int err) | |
1114 | { | |
1115 | if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) | |
1116 | panic("I/O error reading memory image"); | |
1117 | atomic_set(&io_done, 0); | |
1118 | return 0; | |
1119 | } | |
1120 | ||
1121 | static struct block_device * resume_bdev; | |
1122 | ||
1123 | /** | |
1124 | * submit - submit BIO request. | |
1125 | * @rw: READ or WRITE. | |
1126 | * @off physical offset of page. | |
1127 | * @page: page we're reading or writing. | |
1128 | * | |
1129 | * Straight from the textbook - allocate and initialize the bio. | |
1130 | * If we're writing, make sure the page is marked as dirty. | |
1131 | * Then submit it and wait. | |
1132 | */ | |
1133 | ||
1134 | static int submit(int rw, pgoff_t page_off, void * page) | |
1135 | { | |
1136 | int error = 0; | |
1137 | struct bio * bio; | |
1138 | ||
1139 | bio = bio_alloc(GFP_ATOMIC, 1); | |
1140 | if (!bio) | |
1141 | return -ENOMEM; | |
1142 | bio->bi_sector = page_off * (PAGE_SIZE >> 9); | |
1143 | bio_get(bio); | |
1144 | bio->bi_bdev = resume_bdev; | |
1145 | bio->bi_end_io = end_io; | |
1146 | ||
1147 | if (bio_add_page(bio, virt_to_page(page), PAGE_SIZE, 0) < PAGE_SIZE) { | |
1148 | printk("swsusp: ERROR: adding page to bio at %ld\n",page_off); | |
1149 | error = -EFAULT; | |
1150 | goto Done; | |
1151 | } | |
1152 | ||
1153 | if (rw == WRITE) | |
1154 | bio_set_pages_dirty(bio); | |
1155 | ||
1156 | atomic_set(&io_done, 1); | |
1157 | submit_bio(rw | (1 << BIO_RW_SYNC), bio); | |
1158 | while (atomic_read(&io_done)) | |
1159 | yield(); | |
1160 | ||
1161 | Done: | |
1162 | bio_put(bio); | |
1163 | return error; | |
1164 | } | |
1165 | ||
1166 | static int bio_read_page(pgoff_t page_off, void * page) | |
1167 | { | |
1168 | return submit(READ, page_off, page); | |
1169 | } | |
1170 | ||
1171 | static int bio_write_page(pgoff_t page_off, void * page) | |
1172 | { | |
1173 | return submit(WRITE, page_off, page); | |
1174 | } | |
1175 | ||
1176 | /* | |
1177 | * Sanity check if this image makes sense with this kernel/swap context | |
1178 | * I really don't think that it's foolproof but more than nothing.. | |
1179 | */ | |
1180 | ||
1181 | static const char * sanity_check(void) | |
1182 | { | |
1183 | dump_info(); | |
1184 | if(swsusp_info.version_code != LINUX_VERSION_CODE) | |
1185 | return "kernel version"; | |
1186 | if(swsusp_info.num_physpages != num_physpages) | |
1187 | return "memory size"; | |
1188 | if (strcmp(swsusp_info.uts.sysname,system_utsname.sysname)) | |
1189 | return "system type"; | |
1190 | if (strcmp(swsusp_info.uts.release,system_utsname.release)) | |
1191 | return "kernel release"; | |
1192 | if (strcmp(swsusp_info.uts.version,system_utsname.version)) | |
1193 | return "version"; | |
1194 | if (strcmp(swsusp_info.uts.machine,system_utsname.machine)) | |
1195 | return "machine"; | |
1196 | if(swsusp_info.cpus != num_online_cpus()) | |
1197 | return "number of cpus"; | |
1198 | return NULL; | |
1199 | } | |
1200 | ||
1201 | ||
1202 | static int check_header(void) | |
1203 | { | |
1204 | const char * reason = NULL; | |
1205 | int error; | |
1206 | ||
1207 | if ((error = bio_read_page(swp_offset(swsusp_header.swsusp_info), &swsusp_info))) | |
1208 | return error; | |
1209 | ||
1210 | /* Is this same machine? */ | |
1211 | if ((reason = sanity_check())) { | |
1212 | printk(KERN_ERR "swsusp: Resume mismatch: %s\n",reason); | |
1213 | return -EPERM; | |
1214 | } | |
1215 | nr_copy_pages = swsusp_info.image_pages; | |
1216 | return error; | |
1217 | } | |
1218 | ||
1219 | static int check_sig(void) | |
1220 | { | |
1221 | int error; | |
1222 | ||
1223 | memset(&swsusp_header, 0, sizeof(swsusp_header)); | |
1224 | if ((error = bio_read_page(0, &swsusp_header))) | |
1225 | return error; | |
1226 | if (!memcmp(SWSUSP_SIG, swsusp_header.sig, 10)) { | |
1227 | memcpy(swsusp_header.sig, swsusp_header.orig_sig, 10); | |
1228 | ||
1229 | /* | |
1230 | * Reset swap signature now. | |
1231 | */ | |
1232 | error = bio_write_page(0, &swsusp_header); | |
1233 | } else { | |
1234 | printk(KERN_ERR "swsusp: Suspend partition has wrong signature?\n"); | |
1235 | return -EINVAL; | |
1236 | } | |
1237 | if (!error) | |
1238 | pr_debug("swsusp: Signature found, resuming\n"); | |
1239 | return error; | |
1240 | } | |
1241 | ||
1242 | /** | |
1243 | * data_read - Read image pages from swap. | |
1244 | * | |
1245 | * You do not need to check for overlaps, check_pagedir() | |
1246 | * already did that. | |
1247 | */ | |
1248 | ||
1249 | static int data_read(struct pbe *pblist) | |
1250 | { | |
1251 | struct pbe * p; | |
1252 | int error = 0; | |
1253 | int i = 0; | |
1254 | int mod = swsusp_info.image_pages / 100; | |
1255 | ||
1256 | if (!mod) | |
1257 | mod = 1; | |
1258 | ||
1259 | printk("swsusp: Reading image data (%lu pages): ", | |
1260 | swsusp_info.image_pages); | |
1261 | ||
1262 | for_each_pbe (p, pblist) { | |
1263 | if (!(i % mod)) | |
1264 | printk("\b\b\b\b%3d%%", i / mod); | |
1265 | ||
1266 | error = bio_read_page(swp_offset(p->swap_address), | |
1267 | (void *)p->address); | |
1268 | if (error) | |
1269 | return error; | |
1270 | ||
1271 | i++; | |
1272 | } | |
1273 | printk("\b\b\b\bdone\n"); | |
1274 | return error; | |
1275 | } | |
1276 | ||
1277 | extern dev_t name_to_dev_t(const char *line); | |
1278 | ||
1279 | /** | |
1280 | * read_pagedir - Read page backup list pages from swap | |
1281 | */ | |
1282 | ||
1283 | static int read_pagedir(struct pbe *pblist) | |
1284 | { | |
1285 | struct pbe *pbpage, *p; | |
1286 | unsigned i = 0; | |
1287 | int error; | |
1288 | ||
1289 | if (!pblist) | |
1290 | return -EFAULT; | |
1291 | ||
1292 | printk("swsusp: Reading pagedir (%lu pages)\n", | |
1293 | swsusp_info.pagedir_pages); | |
1294 | ||
1295 | for_each_pb_page (pbpage, pblist) { | |
1296 | unsigned long offset = swp_offset(swsusp_info.pagedir[i++]); | |
1297 | ||
1298 | error = -EFAULT; | |
1299 | if (offset) { | |
1300 | p = (pbpage + PB_PAGE_SKIP)->next; | |
1301 | error = bio_read_page(offset, (void *)pbpage); | |
1302 | (pbpage + PB_PAGE_SKIP)->next = p; | |
1303 | } | |
1304 | if (error) | |
1305 | break; | |
1306 | } | |
1307 | ||
1308 | if (error) | |
1309 | free_page((unsigned long)pblist); | |
1310 | ||
1311 | BUG_ON(i != swsusp_info.pagedir_pages); | |
1312 | ||
1313 | return error; | |
1314 | } | |
1315 | ||
1316 | ||
1317 | static int check_suspend_image(void) | |
1318 | { | |
1319 | int error = 0; | |
1320 | ||
1321 | if ((error = check_sig())) | |
1322 | return error; | |
1323 | ||
1324 | if ((error = check_header())) | |
1325 | return error; | |
1326 | ||
1327 | return 0; | |
1328 | } | |
1329 | ||
1330 | static int read_suspend_image(void) | |
1331 | { | |
1332 | int error = 0; | |
1333 | struct pbe *p; | |
1334 | ||
1335 | if (!(p = alloc_pagedir(nr_copy_pages))) | |
1336 | return -ENOMEM; | |
1337 | ||
1338 | if ((error = read_pagedir(p))) | |
1339 | return error; | |
1340 | ||
1341 | create_pbe_list(p, nr_copy_pages); | |
1342 | ||
1343 | if (!(pagedir_nosave = swsusp_pagedir_relocate(p))) | |
1344 | return -ENOMEM; | |
1345 | ||
1346 | /* Allocate memory for the image and read the data from swap */ | |
1347 | ||
1348 | error = check_pagedir(pagedir_nosave); | |
1349 | free_eaten_memory(); | |
1350 | if (!error) | |
1351 | error = data_read(pagedir_nosave); | |
1352 | ||
1353 | if (error) { /* We fail cleanly */ | |
1354 | for_each_pbe (p, pagedir_nosave) | |
1355 | if (p->address) { | |
1356 | free_page(p->address); | |
1357 | p->address = 0UL; | |
1358 | } | |
1359 | free_pagedir(pagedir_nosave); | |
1360 | } | |
1361 | return error; | |
1362 | } | |
1363 | ||
1364 | /** | |
1365 | * swsusp_check - Check for saved image in swap | |
1366 | */ | |
1367 | ||
1368 | int swsusp_check(void) | |
1369 | { | |
1370 | int error; | |
1371 | ||
1372 | if (!swsusp_resume_device) { | |
1373 | if (!strlen(resume_file)) | |
1374 | return -ENOENT; | |
1375 | swsusp_resume_device = name_to_dev_t(resume_file); | |
1376 | pr_debug("swsusp: Resume From Partition %s\n", resume_file); | |
1377 | } else { | |
1378 | pr_debug("swsusp: Resume From Partition %d:%d\n", | |
1379 | MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device)); | |
1380 | } | |
1381 | ||
1382 | resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ); | |
1383 | if (!IS_ERR(resume_bdev)) { | |
1384 | set_blocksize(resume_bdev, PAGE_SIZE); | |
1385 | error = check_suspend_image(); | |
1386 | if (error) | |
1387 | blkdev_put(resume_bdev); | |
1388 | } else | |
1389 | error = PTR_ERR(resume_bdev); | |
1390 | ||
1391 | if (!error) | |
1392 | pr_debug("swsusp: resume file found\n"); | |
1393 | else | |
1394 | pr_debug("swsusp: Error %d check for resume file\n", error); | |
1395 | return error; | |
1396 | } | |
1397 | ||
1398 | /** | |
1399 | * swsusp_read - Read saved image from swap. | |
1400 | */ | |
1401 | ||
1402 | int swsusp_read(void) | |
1403 | { | |
1404 | int error; | |
1405 | ||
1406 | if (IS_ERR(resume_bdev)) { | |
1407 | pr_debug("swsusp: block device not initialised\n"); | |
1408 | return PTR_ERR(resume_bdev); | |
1409 | } | |
1410 | ||
1411 | error = read_suspend_image(); | |
1412 | blkdev_put(resume_bdev); | |
1413 | ||
1414 | if (!error) | |
1415 | pr_debug("swsusp: Reading resume file was successful\n"); | |
1416 | else | |
1417 | pr_debug("swsusp: Error %d resuming\n", error); | |
1418 | return error; | |
1419 | } | |
1420 | ||
1421 | /** | |
1422 | * swsusp_close - close swap device. | |
1423 | */ | |
1424 | ||
1425 | void swsusp_close(void) | |
1426 | { | |
1427 | if (IS_ERR(resume_bdev)) { | |
1428 | pr_debug("swsusp: block device not initialised\n"); | |
1429 | return; | |
1430 | } | |
1431 | ||
1432 | blkdev_put(resume_bdev); | |
1433 | } |