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1/*
2 * kernel/power/hibernate.c - Hibernation (a.k.a suspend-to-disk) support.
3 *
4 * Copyright (c) 2003 Patrick Mochel
5 * Copyright (c) 2003 Open Source Development Lab
6 * Copyright (c) 2004 Pavel Machek <pavel@ucw.cz>
7 * Copyright (c) 2009 Rafael J. Wysocki, Novell Inc.
8 *
9 * This file is released under the GPLv2.
10 */
11
12#include <linux/suspend.h>
13#include <linux/syscalls.h>
14#include <linux/reboot.h>
15#include <linux/string.h>
16#include <linux/device.h>
17#include <linux/kmod.h>
18#include <linux/delay.h>
19#include <linux/fs.h>
20#include <linux/mount.h>
21#include <linux/pm.h>
22#include <linux/console.h>
23#include <linux/cpu.h>
24#include <linux/freezer.h>
25#include <linux/gfp.h>
26#include <linux/syscore_ops.h>
27#include <scsi/scsi_scan.h>
28
29#include "power.h"
30
31
32static int nocompress = 0;
33static int noresume = 0;
34static char resume_file[256] = CONFIG_PM_STD_PARTITION;
35dev_t swsusp_resume_device;
36sector_t swsusp_resume_block;
37int in_suspend __nosavedata = 0;
38
39enum {
40 HIBERNATION_INVALID,
41 HIBERNATION_PLATFORM,
42 HIBERNATION_TEST,
43 HIBERNATION_TESTPROC,
44 HIBERNATION_SHUTDOWN,
45 HIBERNATION_REBOOT,
46 /* keep last */
47 __HIBERNATION_AFTER_LAST
48};
49#define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
50#define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
51
52static int hibernation_mode = HIBERNATION_SHUTDOWN;
53
54static const struct platform_hibernation_ops *hibernation_ops;
55
56/**
57 * hibernation_set_ops - Set the global hibernate operations.
58 * @ops: Hibernation operations to use in subsequent hibernation transitions.
59 */
60void hibernation_set_ops(const struct platform_hibernation_ops *ops)
61{
62 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
63 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
64 && ops->restore_cleanup && ops->leave)) {
65 WARN_ON(1);
66 return;
67 }
68 mutex_lock(&pm_mutex);
69 hibernation_ops = ops;
70 if (ops)
71 hibernation_mode = HIBERNATION_PLATFORM;
72 else if (hibernation_mode == HIBERNATION_PLATFORM)
73 hibernation_mode = HIBERNATION_SHUTDOWN;
74
75 mutex_unlock(&pm_mutex);
76}
77
78static bool entering_platform_hibernation;
79
80bool system_entering_hibernation(void)
81{
82 return entering_platform_hibernation;
83}
84EXPORT_SYMBOL(system_entering_hibernation);
85
86#ifdef CONFIG_PM_DEBUG
87static void hibernation_debug_sleep(void)
88{
89 printk(KERN_INFO "hibernation debug: Waiting for 5 seconds.\n");
90 mdelay(5000);
91}
92
93static int hibernation_testmode(int mode)
94{
95 if (hibernation_mode == mode) {
96 hibernation_debug_sleep();
97 return 1;
98 }
99 return 0;
100}
101
102static int hibernation_test(int level)
103{
104 if (pm_test_level == level) {
105 hibernation_debug_sleep();
106 return 1;
107 }
108 return 0;
109}
110#else /* !CONFIG_PM_DEBUG */
111static int hibernation_testmode(int mode) { return 0; }
112static int hibernation_test(int level) { return 0; }
113#endif /* !CONFIG_PM_DEBUG */
114
115/**
116 * platform_begin - Call platform to start hibernation.
117 * @platform_mode: Whether or not to use the platform driver.
118 */
119static int platform_begin(int platform_mode)
120{
121 return (platform_mode && hibernation_ops) ?
122 hibernation_ops->begin() : 0;
123}
124
125/**
126 * platform_end - Call platform to finish transition to the working state.
127 * @platform_mode: Whether or not to use the platform driver.
128 */
129static void platform_end(int platform_mode)
130{
131 if (platform_mode && hibernation_ops)
132 hibernation_ops->end();
133}
134
135/**
136 * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
137 * @platform_mode: Whether or not to use the platform driver.
138 *
139 * Use the platform driver to prepare the system for creating a hibernate image,
140 * if so configured, and return an error code if that fails.
141 */
142
143static int platform_pre_snapshot(int platform_mode)
144{
145 return (platform_mode && hibernation_ops) ?
146 hibernation_ops->pre_snapshot() : 0;
147}
148
149/**
150 * platform_leave - Call platform to prepare a transition to the working state.
151 * @platform_mode: Whether or not to use the platform driver.
152 *
153 * Use the platform driver prepare to prepare the machine for switching to the
154 * normal mode of operation.
155 *
156 * This routine is called on one CPU with interrupts disabled.
157 */
158static void platform_leave(int platform_mode)
159{
160 if (platform_mode && hibernation_ops)
161 hibernation_ops->leave();
162}
163
164/**
165 * platform_finish - Call platform to switch the system to the working state.
166 * @platform_mode: Whether or not to use the platform driver.
167 *
168 * Use the platform driver to switch the machine to the normal mode of
169 * operation.
170 *
171 * This routine must be called after platform_prepare().
172 */
173static void platform_finish(int platform_mode)
174{
175 if (platform_mode && hibernation_ops)
176 hibernation_ops->finish();
177}
178
179/**
180 * platform_pre_restore - Prepare for hibernate image restoration.
181 * @platform_mode: Whether or not to use the platform driver.
182 *
183 * Use the platform driver to prepare the system for resume from a hibernation
184 * image.
185 *
186 * If the restore fails after this function has been called,
187 * platform_restore_cleanup() must be called.
188 */
189static int platform_pre_restore(int platform_mode)
190{
191 return (platform_mode && hibernation_ops) ?
192 hibernation_ops->pre_restore() : 0;
193}
194
195/**
196 * platform_restore_cleanup - Switch to the working state after failing restore.
197 * @platform_mode: Whether or not to use the platform driver.
198 *
199 * Use the platform driver to switch the system to the normal mode of operation
200 * after a failing restore.
201 *
202 * If platform_pre_restore() has been called before the failing restore, this
203 * function must be called too, regardless of the result of
204 * platform_pre_restore().
205 */
206static void platform_restore_cleanup(int platform_mode)
207{
208 if (platform_mode && hibernation_ops)
209 hibernation_ops->restore_cleanup();
210}
211
212/**
213 * platform_recover - Recover from a failure to suspend devices.
214 * @platform_mode: Whether or not to use the platform driver.
215 */
216static void platform_recover(int platform_mode)
217{
218 if (platform_mode && hibernation_ops && hibernation_ops->recover)
219 hibernation_ops->recover();
220}
221
222/**
223 * swsusp_show_speed - Print time elapsed between two events during hibernation.
224 * @start: Starting event.
225 * @stop: Final event.
226 * @nr_pages: Number of memory pages processed between @start and @stop.
227 * @msg: Additional diagnostic message to print.
228 */
229void swsusp_show_speed(struct timeval *start, struct timeval *stop,
230 unsigned nr_pages, char *msg)
231{
232 s64 elapsed_centisecs64;
233 int centisecs;
234 int k;
235 int kps;
236
237 elapsed_centisecs64 = timeval_to_ns(stop) - timeval_to_ns(start);
238 do_div(elapsed_centisecs64, NSEC_PER_SEC / 100);
239 centisecs = elapsed_centisecs64;
240 if (centisecs == 0)
241 centisecs = 1; /* avoid div-by-zero */
242 k = nr_pages * (PAGE_SIZE / 1024);
243 kps = (k * 100) / centisecs;
244 printk(KERN_INFO "PM: %s %d kbytes in %d.%02d seconds (%d.%02d MB/s)\n",
245 msg, k,
246 centisecs / 100, centisecs % 100,
247 kps / 1000, (kps % 1000) / 10);
248}
249
250/**
251 * create_image - Create a hibernation image.
252 * @platform_mode: Whether or not to use the platform driver.
253 *
254 * Execute device drivers' .freeze_noirq() callbacks, create a hibernation image
255 * and execute the drivers' .thaw_noirq() callbacks.
256 *
257 * Control reappears in this routine after the subsequent restore.
258 */
259static int create_image(int platform_mode)
260{
261 int error;
262
263 error = dpm_suspend_noirq(PMSG_FREEZE);
264 if (error) {
265 printk(KERN_ERR "PM: Some devices failed to power down, "
266 "aborting hibernation\n");
267 return error;
268 }
269
270 error = platform_pre_snapshot(platform_mode);
271 if (error || hibernation_test(TEST_PLATFORM))
272 goto Platform_finish;
273
274 error = disable_nonboot_cpus();
275 if (error || hibernation_test(TEST_CPUS)
276 || hibernation_testmode(HIBERNATION_TEST))
277 goto Enable_cpus;
278
279 local_irq_disable();
280
281 error = syscore_suspend();
282 if (error) {
283 printk(KERN_ERR "PM: Some system devices failed to power down, "
284 "aborting hibernation\n");
285 goto Enable_irqs;
286 }
287
288 if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
289 goto Power_up;
290
291 in_suspend = 1;
292 save_processor_state();
293 error = swsusp_arch_suspend();
294 if (error)
295 printk(KERN_ERR "PM: Error %d creating hibernation image\n",
296 error);
297 /* Restore control flow magically appears here */
298 restore_processor_state();
299 if (!in_suspend) {
300 events_check_enabled = false;
301 platform_leave(platform_mode);
302 }
303
304 Power_up:
305 syscore_resume();
306
307 Enable_irqs:
308 local_irq_enable();
309
310 Enable_cpus:
311 enable_nonboot_cpus();
312
313 Platform_finish:
314 platform_finish(platform_mode);
315
316 dpm_resume_noirq(in_suspend ?
317 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
318
319 return error;
320}
321
322/**
323 * hibernation_snapshot - Quiesce devices and create a hibernation image.
324 * @platform_mode: If set, use platform driver to prepare for the transition.
325 *
326 * This routine must be called with pm_mutex held.
327 */
328int hibernation_snapshot(int platform_mode)
329{
330 pm_message_t msg = PMSG_RECOVER;
331 int error;
332
333 error = platform_begin(platform_mode);
334 if (error)
335 goto Close;
336
337 error = dpm_prepare(PMSG_FREEZE);
338 if (error)
339 goto Complete_devices;
340
341 /* Preallocate image memory before shutting down devices. */
342 error = hibernate_preallocate_memory();
343 if (error)
344 goto Complete_devices;
345
346 suspend_console();
347 pm_restrict_gfp_mask();
348 error = dpm_suspend(PMSG_FREEZE);
349 if (error)
350 goto Recover_platform;
351
352 if (hibernation_test(TEST_DEVICES))
353 goto Recover_platform;
354
355 error = create_image(platform_mode);
356 /*
357 * Control returns here (1) after the image has been created or the
358 * image creation has failed and (2) after a successful restore.
359 */
360
361 Resume_devices:
362 /* We may need to release the preallocated image pages here. */
363 if (error || !in_suspend)
364 swsusp_free();
365
366 msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
367 dpm_resume(msg);
368
369 if (error || !in_suspend)
370 pm_restore_gfp_mask();
371
372 resume_console();
373
374 Complete_devices:
375 dpm_complete(msg);
376
377 Close:
378 platform_end(platform_mode);
379 return error;
380
381 Recover_platform:
382 platform_recover(platform_mode);
383 goto Resume_devices;
384}
385
386/**
387 * resume_target_kernel - Restore system state from a hibernation image.
388 * @platform_mode: Whether or not to use the platform driver.
389 *
390 * Execute device drivers' .freeze_noirq() callbacks, restore the contents of
391 * highmem that have not been restored yet from the image and run the low-level
392 * code that will restore the remaining contents of memory and switch to the
393 * just restored target kernel.
394 */
395static int resume_target_kernel(bool platform_mode)
396{
397 int error;
398
399 error = dpm_suspend_noirq(PMSG_QUIESCE);
400 if (error) {
401 printk(KERN_ERR "PM: Some devices failed to power down, "
402 "aborting resume\n");
403 return error;
404 }
405
406 error = platform_pre_restore(platform_mode);
407 if (error)
408 goto Cleanup;
409
410 error = disable_nonboot_cpus();
411 if (error)
412 goto Enable_cpus;
413
414 local_irq_disable();
415
416 error = syscore_suspend();
417 if (error)
418 goto Enable_irqs;
419
420 save_processor_state();
421 error = restore_highmem();
422 if (!error) {
423 error = swsusp_arch_resume();
424 /*
425 * The code below is only ever reached in case of a failure.
426 * Otherwise, execution continues at the place where
427 * swsusp_arch_suspend() was called.
428 */
429 BUG_ON(!error);
430 /*
431 * This call to restore_highmem() reverts the changes made by
432 * the previous one.
433 */
434 restore_highmem();
435 }
436 /*
437 * The only reason why swsusp_arch_resume() can fail is memory being
438 * very tight, so we have to free it as soon as we can to avoid
439 * subsequent failures.
440 */
441 swsusp_free();
442 restore_processor_state();
443 touch_softlockup_watchdog();
444
445 syscore_resume();
446
447 Enable_irqs:
448 local_irq_enable();
449
450 Enable_cpus:
451 enable_nonboot_cpus();
452
453 Cleanup:
454 platform_restore_cleanup(platform_mode);
455
456 dpm_resume_noirq(PMSG_RECOVER);
457
458 return error;
459}
460
461/**
462 * hibernation_restore - Quiesce devices and restore from a hibernation image.
463 * @platform_mode: If set, use platform driver to prepare for the transition.
464 *
465 * This routine must be called with pm_mutex held. If it is successful, control
466 * reappears in the restored target kernel in hibernation_snaphot().
467 */
468int hibernation_restore(int platform_mode)
469{
470 int error;
471
472 pm_prepare_console();
473 suspend_console();
474 pm_restrict_gfp_mask();
475 error = dpm_suspend_start(PMSG_QUIESCE);
476 if (!error) {
477 error = resume_target_kernel(platform_mode);
478 dpm_resume_end(PMSG_RECOVER);
479 }
480 pm_restore_gfp_mask();
481 resume_console();
482 pm_restore_console();
483 return error;
484}
485
486/**
487 * hibernation_platform_enter - Power off the system using the platform driver.
488 */
489int hibernation_platform_enter(void)
490{
491 int error;
492
493 if (!hibernation_ops)
494 return -ENOSYS;
495
496 /*
497 * We have cancelled the power transition by running
498 * hibernation_ops->finish() before saving the image, so we should let
499 * the firmware know that we're going to enter the sleep state after all
500 */
501 error = hibernation_ops->begin();
502 if (error)
503 goto Close;
504
505 entering_platform_hibernation = true;
506 suspend_console();
507 error = dpm_suspend_start(PMSG_HIBERNATE);
508 if (error) {
509 if (hibernation_ops->recover)
510 hibernation_ops->recover();
511 goto Resume_devices;
512 }
513
514 error = dpm_suspend_noirq(PMSG_HIBERNATE);
515 if (error)
516 goto Resume_devices;
517
518 error = hibernation_ops->prepare();
519 if (error)
520 goto Platform_finish;
521
522 error = disable_nonboot_cpus();
523 if (error)
524 goto Platform_finish;
525
526 local_irq_disable();
527 syscore_suspend();
528 if (pm_wakeup_pending()) {
529 error = -EAGAIN;
530 goto Power_up;
531 }
532
533 hibernation_ops->enter();
534 /* We should never get here */
535 while (1);
536
537 Power_up:
538 syscore_resume();
539 local_irq_enable();
540 enable_nonboot_cpus();
541
542 Platform_finish:
543 hibernation_ops->finish();
544
545 dpm_resume_noirq(PMSG_RESTORE);
546
547 Resume_devices:
548 entering_platform_hibernation = false;
549 dpm_resume_end(PMSG_RESTORE);
550 resume_console();
551
552 Close:
553 hibernation_ops->end();
554
555 return error;
556}
557
558/**
559 * power_down - Shut the machine down for hibernation.
560 *
561 * Use the platform driver, if configured, to put the system into the sleep
562 * state corresponding to hibernation, or try to power it off or reboot,
563 * depending on the value of hibernation_mode.
564 */
565static void power_down(void)
566{
567 switch (hibernation_mode) {
568 case HIBERNATION_TEST:
569 case HIBERNATION_TESTPROC:
570 break;
571 case HIBERNATION_REBOOT:
572 kernel_restart(NULL);
573 break;
574 case HIBERNATION_PLATFORM:
575 hibernation_platform_enter();
576 case HIBERNATION_SHUTDOWN:
577 kernel_power_off();
578 break;
579 }
580 kernel_halt();
581 /*
582 * Valid image is on the disk, if we continue we risk serious data
583 * corruption after resume.
584 */
585 printk(KERN_CRIT "PM: Please power down manually\n");
586 while(1);
587}
588
589static int prepare_processes(void)
590{
591 int error = 0;
592
593 if (freeze_processes()) {
594 error = -EBUSY;
595 thaw_processes();
596 }
597 return error;
598}
599
600/**
601 * hibernate - Carry out system hibernation, including saving the image.
602 */
603int hibernate(void)
604{
605 int error;
606
607 mutex_lock(&pm_mutex);
608 /* The snapshot device should not be opened while we're running */
609 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
610 error = -EBUSY;
611 goto Unlock;
612 }
613
614 pm_prepare_console();
615 error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
616 if (error)
617 goto Exit;
618
619 error = usermodehelper_disable();
620 if (error)
621 goto Exit;
622
623 /* Allocate memory management structures */
624 error = create_basic_memory_bitmaps();
625 if (error)
626 goto Exit;
627
628 printk(KERN_INFO "PM: Syncing filesystems ... ");
629 sys_sync();
630 printk("done.\n");
631
632 error = prepare_processes();
633 if (error)
634 goto Finish;
635
636 if (hibernation_test(TEST_FREEZER))
637 goto Thaw;
638
639 if (hibernation_testmode(HIBERNATION_TESTPROC))
640 goto Thaw;
641
642 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
643 if (error)
644 goto Thaw;
645
646 if (in_suspend) {
647 unsigned int flags = 0;
648
649 if (hibernation_mode == HIBERNATION_PLATFORM)
650 flags |= SF_PLATFORM_MODE;
651 if (nocompress)
652 flags |= SF_NOCOMPRESS_MODE;
653 pr_debug("PM: writing image.\n");
654 error = swsusp_write(flags);
655 swsusp_free();
656 if (!error)
657 power_down();
658 in_suspend = 0;
659 pm_restore_gfp_mask();
660 } else {
661 pr_debug("PM: Image restored successfully.\n");
662 }
663
664 Thaw:
665 thaw_processes();
666 Finish:
667 free_basic_memory_bitmaps();
668 usermodehelper_enable();
669 Exit:
670 pm_notifier_call_chain(PM_POST_HIBERNATION);
671 pm_restore_console();
672 atomic_inc(&snapshot_device_available);
673 Unlock:
674 mutex_unlock(&pm_mutex);
675 return error;
676}
677
678
679/**
680 * software_resume - Resume from a saved hibernation image.
681 *
682 * This routine is called as a late initcall, when all devices have been
683 * discovered and initialized already.
684 *
685 * The image reading code is called to see if there is a hibernation image
686 * available for reading. If that is the case, devices are quiesced and the
687 * contents of memory is restored from the saved image.
688 *
689 * If this is successful, control reappears in the restored target kernel in
690 * hibernation_snaphot() which returns to hibernate(). Otherwise, the routine
691 * attempts to recover gracefully and make the kernel return to the normal mode
692 * of operation.
693 */
694static int software_resume(void)
695{
696 int error;
697 unsigned int flags;
698
699 /*
700 * If the user said "noresume".. bail out early.
701 */
702 if (noresume)
703 return 0;
704
705 /*
706 * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
707 * is configured into the kernel. Since the regular hibernate
708 * trigger path is via sysfs which takes a buffer mutex before
709 * calling hibernate functions (which take pm_mutex) this can
710 * cause lockdep to complain about a possible ABBA deadlock
711 * which cannot happen since we're in the boot code here and
712 * sysfs can't be invoked yet. Therefore, we use a subclass
713 * here to avoid lockdep complaining.
714 */
715 mutex_lock_nested(&pm_mutex, SINGLE_DEPTH_NESTING);
716
717 if (swsusp_resume_device)
718 goto Check_image;
719
720 if (!strlen(resume_file)) {
721 error = -ENOENT;
722 goto Unlock;
723 }
724
725 pr_debug("PM: Checking hibernation image partition %s\n", resume_file);
726
727 /* Check if the device is there */
728 swsusp_resume_device = name_to_dev_t(resume_file);
729 if (!swsusp_resume_device) {
730 /*
731 * Some device discovery might still be in progress; we need
732 * to wait for this to finish.
733 */
734 wait_for_device_probe();
735 /*
736 * We can't depend on SCSI devices being available after loading
737 * one of their modules until scsi_complete_async_scans() is
738 * called and the resume device usually is a SCSI one.
739 */
740 scsi_complete_async_scans();
741
742 swsusp_resume_device = name_to_dev_t(resume_file);
743 if (!swsusp_resume_device) {
744 error = -ENODEV;
745 goto Unlock;
746 }
747 }
748
749 Check_image:
750 pr_debug("PM: Hibernation image partition %d:%d present\n",
751 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
752
753 pr_debug("PM: Looking for hibernation image.\n");
754 error = swsusp_check();
755 if (error)
756 goto Unlock;
757
758 /* The snapshot device should not be opened while we're running */
759 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
760 error = -EBUSY;
761 swsusp_close(FMODE_READ);
762 goto Unlock;
763 }
764
765 pm_prepare_console();
766 error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
767 if (error)
768 goto close_finish;
769
770 error = usermodehelper_disable();
771 if (error)
772 goto close_finish;
773
774 error = create_basic_memory_bitmaps();
775 if (error)
776 goto close_finish;
777
778 pr_debug("PM: Preparing processes for restore.\n");
779 error = prepare_processes();
780 if (error) {
781 swsusp_close(FMODE_READ);
782 goto Done;
783 }
784
785 pr_debug("PM: Loading hibernation image.\n");
786
787 error = swsusp_read(&flags);
788 swsusp_close(FMODE_READ);
789 if (!error)
790 hibernation_restore(flags & SF_PLATFORM_MODE);
791
792 printk(KERN_ERR "PM: Failed to load hibernation image, recovering.\n");
793 swsusp_free();
794 thaw_processes();
795 Done:
796 free_basic_memory_bitmaps();
797 usermodehelper_enable();
798 Finish:
799 pm_notifier_call_chain(PM_POST_RESTORE);
800 pm_restore_console();
801 atomic_inc(&snapshot_device_available);
802 /* For success case, the suspend path will release the lock */
803 Unlock:
804 mutex_unlock(&pm_mutex);
805 pr_debug("PM: Hibernation image not present or could not be loaded.\n");
806 return error;
807close_finish:
808 swsusp_close(FMODE_READ);
809 goto Finish;
810}
811
812late_initcall(software_resume);
813
814
815static const char * const hibernation_modes[] = {
816 [HIBERNATION_PLATFORM] = "platform",
817 [HIBERNATION_SHUTDOWN] = "shutdown",
818 [HIBERNATION_REBOOT] = "reboot",
819 [HIBERNATION_TEST] = "test",
820 [HIBERNATION_TESTPROC] = "testproc",
821};
822
823/*
824 * /sys/power/disk - Control hibernation mode.
825 *
826 * Hibernation can be handled in several ways. There are a few different ways
827 * to put the system into the sleep state: using the platform driver (e.g. ACPI
828 * or other hibernation_ops), powering it off or rebooting it (for testing
829 * mostly), or using one of the two available test modes.
830 *
831 * The sysfs file /sys/power/disk provides an interface for selecting the
832 * hibernation mode to use. Reading from this file causes the available modes
833 * to be printed. There are 5 modes that can be supported:
834 *
835 * 'platform'
836 * 'shutdown'
837 * 'reboot'
838 * 'test'
839 * 'testproc'
840 *
841 * If a platform hibernation driver is in use, 'platform' will be supported
842 * and will be used by default. Otherwise, 'shutdown' will be used by default.
843 * The selected option (i.e. the one corresponding to the current value of
844 * hibernation_mode) is enclosed by a square bracket.
845 *
846 * To select a given hibernation mode it is necessary to write the mode's
847 * string representation (as returned by reading from /sys/power/disk) back
848 * into /sys/power/disk.
849 */
850
851static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
852 char *buf)
853{
854 int i;
855 char *start = buf;
856
857 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
858 if (!hibernation_modes[i])
859 continue;
860 switch (i) {
861 case HIBERNATION_SHUTDOWN:
862 case HIBERNATION_REBOOT:
863 case HIBERNATION_TEST:
864 case HIBERNATION_TESTPROC:
865 break;
866 case HIBERNATION_PLATFORM:
867 if (hibernation_ops)
868 break;
869 /* not a valid mode, continue with loop */
870 continue;
871 }
872 if (i == hibernation_mode)
873 buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
874 else
875 buf += sprintf(buf, "%s ", hibernation_modes[i]);
876 }
877 buf += sprintf(buf, "\n");
878 return buf-start;
879}
880
881static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
882 const char *buf, size_t n)
883{
884 int error = 0;
885 int i;
886 int len;
887 char *p;
888 int mode = HIBERNATION_INVALID;
889
890 p = memchr(buf, '\n', n);
891 len = p ? p - buf : n;
892
893 mutex_lock(&pm_mutex);
894 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
895 if (len == strlen(hibernation_modes[i])
896 && !strncmp(buf, hibernation_modes[i], len)) {
897 mode = i;
898 break;
899 }
900 }
901 if (mode != HIBERNATION_INVALID) {
902 switch (mode) {
903 case HIBERNATION_SHUTDOWN:
904 case HIBERNATION_REBOOT:
905 case HIBERNATION_TEST:
906 case HIBERNATION_TESTPROC:
907 hibernation_mode = mode;
908 break;
909 case HIBERNATION_PLATFORM:
910 if (hibernation_ops)
911 hibernation_mode = mode;
912 else
913 error = -EINVAL;
914 }
915 } else
916 error = -EINVAL;
917
918 if (!error)
919 pr_debug("PM: Hibernation mode set to '%s'\n",
920 hibernation_modes[mode]);
921 mutex_unlock(&pm_mutex);
922 return error ? error : n;
923}
924
925power_attr(disk);
926
927static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
928 char *buf)
929{
930 return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
931 MINOR(swsusp_resume_device));
932}
933
934static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
935 const char *buf, size_t n)
936{
937 unsigned int maj, min;
938 dev_t res;
939 int ret = -EINVAL;
940
941 if (sscanf(buf, "%u:%u", &maj, &min) != 2)
942 goto out;
943
944 res = MKDEV(maj,min);
945 if (maj != MAJOR(res) || min != MINOR(res))
946 goto out;
947
948 mutex_lock(&pm_mutex);
949 swsusp_resume_device = res;
950 mutex_unlock(&pm_mutex);
951 printk(KERN_INFO "PM: Starting manual resume from disk\n");
952 noresume = 0;
953 software_resume();
954 ret = n;
955 out:
956 return ret;
957}
958
959power_attr(resume);
960
961static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
962 char *buf)
963{
964 return sprintf(buf, "%lu\n", image_size);
965}
966
967static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
968 const char *buf, size_t n)
969{
970 unsigned long size;
971
972 if (sscanf(buf, "%lu", &size) == 1) {
973 image_size = size;
974 return n;
975 }
976
977 return -EINVAL;
978}
979
980power_attr(image_size);
981
982static ssize_t reserved_size_show(struct kobject *kobj,
983 struct kobj_attribute *attr, char *buf)
984{
985 return sprintf(buf, "%lu\n", reserved_size);
986}
987
988static ssize_t reserved_size_store(struct kobject *kobj,
989 struct kobj_attribute *attr,
990 const char *buf, size_t n)
991{
992 unsigned long size;
993
994 if (sscanf(buf, "%lu", &size) == 1) {
995 reserved_size = size;
996 return n;
997 }
998
999 return -EINVAL;
1000}
1001
1002power_attr(reserved_size);
1003
1004static struct attribute * g[] = {
1005 &disk_attr.attr,
1006 &resume_attr.attr,
1007 &image_size_attr.attr,
1008 &reserved_size_attr.attr,
1009 NULL,
1010};
1011
1012
1013static struct attribute_group attr_group = {
1014 .attrs = g,
1015};
1016
1017
1018static int __init pm_disk_init(void)
1019{
1020 return sysfs_create_group(power_kobj, &attr_group);
1021}
1022
1023core_initcall(pm_disk_init);
1024
1025
1026static int __init resume_setup(char *str)
1027{
1028 if (noresume)
1029 return 1;
1030
1031 strncpy( resume_file, str, 255 );
1032 return 1;
1033}
1034
1035static int __init resume_offset_setup(char *str)
1036{
1037 unsigned long long offset;
1038
1039 if (noresume)
1040 return 1;
1041
1042 if (sscanf(str, "%llu", &offset) == 1)
1043 swsusp_resume_block = offset;
1044
1045 return 1;
1046}
1047
1048static int __init hibernate_setup(char *str)
1049{
1050 if (!strncmp(str, "noresume", 8))
1051 noresume = 1;
1052 else if (!strncmp(str, "nocompress", 10))
1053 nocompress = 1;
1054 return 1;
1055}
1056
1057static int __init noresume_setup(char *str)
1058{
1059 noresume = 1;
1060 return 1;
1061}
1062
1063__setup("noresume", noresume_setup);
1064__setup("resume_offset=", resume_offset_setup);
1065__setup("resume=", resume_setup);
1066__setup("hibernate=", hibernate_setup);
1/*
2 * kernel/power/hibernate.c - Hibernation (a.k.a suspend-to-disk) support.
3 *
4 * Copyright (c) 2003 Patrick Mochel
5 * Copyright (c) 2003 Open Source Development Lab
6 * Copyright (c) 2004 Pavel Machek <pavel@ucw.cz>
7 * Copyright (c) 2009 Rafael J. Wysocki, Novell Inc.
8 *
9 * This file is released under the GPLv2.
10 */
11
12#include <linux/export.h>
13#include <linux/suspend.h>
14#include <linux/syscalls.h>
15#include <linux/reboot.h>
16#include <linux/string.h>
17#include <linux/device.h>
18#include <linux/async.h>
19#include <linux/delay.h>
20#include <linux/fs.h>
21#include <linux/mount.h>
22#include <linux/pm.h>
23#include <linux/console.h>
24#include <linux/cpu.h>
25#include <linux/freezer.h>
26#include <linux/gfp.h>
27#include <linux/syscore_ops.h>
28#include <linux/ctype.h>
29#include <linux/genhd.h>
30
31#include "power.h"
32
33
34static int nocompress;
35static int noresume;
36static int resume_wait;
37static int resume_delay;
38static char resume_file[256] = CONFIG_PM_STD_PARTITION;
39dev_t swsusp_resume_device;
40sector_t swsusp_resume_block;
41int in_suspend __nosavedata;
42
43enum {
44 HIBERNATION_INVALID,
45 HIBERNATION_PLATFORM,
46 HIBERNATION_SHUTDOWN,
47 HIBERNATION_REBOOT,
48 /* keep last */
49 __HIBERNATION_AFTER_LAST
50};
51#define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
52#define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
53
54static int hibernation_mode = HIBERNATION_SHUTDOWN;
55
56bool freezer_test_done;
57
58static const struct platform_hibernation_ops *hibernation_ops;
59
60/**
61 * hibernation_set_ops - Set the global hibernate operations.
62 * @ops: Hibernation operations to use in subsequent hibernation transitions.
63 */
64void hibernation_set_ops(const struct platform_hibernation_ops *ops)
65{
66 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
67 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
68 && ops->restore_cleanup && ops->leave)) {
69 WARN_ON(1);
70 return;
71 }
72 lock_system_sleep();
73 hibernation_ops = ops;
74 if (ops)
75 hibernation_mode = HIBERNATION_PLATFORM;
76 else if (hibernation_mode == HIBERNATION_PLATFORM)
77 hibernation_mode = HIBERNATION_SHUTDOWN;
78
79 unlock_system_sleep();
80}
81
82static bool entering_platform_hibernation;
83
84bool system_entering_hibernation(void)
85{
86 return entering_platform_hibernation;
87}
88EXPORT_SYMBOL(system_entering_hibernation);
89
90#ifdef CONFIG_PM_DEBUG
91static void hibernation_debug_sleep(void)
92{
93 printk(KERN_INFO "hibernation debug: Waiting for 5 seconds.\n");
94 mdelay(5000);
95}
96
97static int hibernation_test(int level)
98{
99 if (pm_test_level == level) {
100 hibernation_debug_sleep();
101 return 1;
102 }
103 return 0;
104}
105#else /* !CONFIG_PM_DEBUG */
106static int hibernation_test(int level) { return 0; }
107#endif /* !CONFIG_PM_DEBUG */
108
109/**
110 * platform_begin - Call platform to start hibernation.
111 * @platform_mode: Whether or not to use the platform driver.
112 */
113static int platform_begin(int platform_mode)
114{
115 return (platform_mode && hibernation_ops) ?
116 hibernation_ops->begin() : 0;
117}
118
119/**
120 * platform_end - Call platform to finish transition to the working state.
121 * @platform_mode: Whether or not to use the platform driver.
122 */
123static void platform_end(int platform_mode)
124{
125 if (platform_mode && hibernation_ops)
126 hibernation_ops->end();
127}
128
129/**
130 * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
131 * @platform_mode: Whether or not to use the platform driver.
132 *
133 * Use the platform driver to prepare the system for creating a hibernate image,
134 * if so configured, and return an error code if that fails.
135 */
136
137static int platform_pre_snapshot(int platform_mode)
138{
139 return (platform_mode && hibernation_ops) ?
140 hibernation_ops->pre_snapshot() : 0;
141}
142
143/**
144 * platform_leave - Call platform to prepare a transition to the working state.
145 * @platform_mode: Whether or not to use the platform driver.
146 *
147 * Use the platform driver prepare to prepare the machine for switching to the
148 * normal mode of operation.
149 *
150 * This routine is called on one CPU with interrupts disabled.
151 */
152static void platform_leave(int platform_mode)
153{
154 if (platform_mode && hibernation_ops)
155 hibernation_ops->leave();
156}
157
158/**
159 * platform_finish - Call platform to switch the system to the working state.
160 * @platform_mode: Whether or not to use the platform driver.
161 *
162 * Use the platform driver to switch the machine to the normal mode of
163 * operation.
164 *
165 * This routine must be called after platform_prepare().
166 */
167static void platform_finish(int platform_mode)
168{
169 if (platform_mode && hibernation_ops)
170 hibernation_ops->finish();
171}
172
173/**
174 * platform_pre_restore - Prepare for hibernate image restoration.
175 * @platform_mode: Whether or not to use the platform driver.
176 *
177 * Use the platform driver to prepare the system for resume from a hibernation
178 * image.
179 *
180 * If the restore fails after this function has been called,
181 * platform_restore_cleanup() must be called.
182 */
183static int platform_pre_restore(int platform_mode)
184{
185 return (platform_mode && hibernation_ops) ?
186 hibernation_ops->pre_restore() : 0;
187}
188
189/**
190 * platform_restore_cleanup - Switch to the working state after failing restore.
191 * @platform_mode: Whether or not to use the platform driver.
192 *
193 * Use the platform driver to switch the system to the normal mode of operation
194 * after a failing restore.
195 *
196 * If platform_pre_restore() has been called before the failing restore, this
197 * function must be called too, regardless of the result of
198 * platform_pre_restore().
199 */
200static void platform_restore_cleanup(int platform_mode)
201{
202 if (platform_mode && hibernation_ops)
203 hibernation_ops->restore_cleanup();
204}
205
206/**
207 * platform_recover - Recover from a failure to suspend devices.
208 * @platform_mode: Whether or not to use the platform driver.
209 */
210static void platform_recover(int platform_mode)
211{
212 if (platform_mode && hibernation_ops && hibernation_ops->recover)
213 hibernation_ops->recover();
214}
215
216/**
217 * swsusp_show_speed - Print time elapsed between two events during hibernation.
218 * @start: Starting event.
219 * @stop: Final event.
220 * @nr_pages: Number of memory pages processed between @start and @stop.
221 * @msg: Additional diagnostic message to print.
222 */
223void swsusp_show_speed(struct timeval *start, struct timeval *stop,
224 unsigned nr_pages, char *msg)
225{
226 s64 elapsed_centisecs64;
227 int centisecs;
228 int k;
229 int kps;
230
231 elapsed_centisecs64 = timeval_to_ns(stop) - timeval_to_ns(start);
232 do_div(elapsed_centisecs64, NSEC_PER_SEC / 100);
233 centisecs = elapsed_centisecs64;
234 if (centisecs == 0)
235 centisecs = 1; /* avoid div-by-zero */
236 k = nr_pages * (PAGE_SIZE / 1024);
237 kps = (k * 100) / centisecs;
238 printk(KERN_INFO "PM: %s %d kbytes in %d.%02d seconds (%d.%02d MB/s)\n",
239 msg, k,
240 centisecs / 100, centisecs % 100,
241 kps / 1000, (kps % 1000) / 10);
242}
243
244/**
245 * create_image - Create a hibernation image.
246 * @platform_mode: Whether or not to use the platform driver.
247 *
248 * Execute device drivers' "late" and "noirq" freeze callbacks, create a
249 * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
250 *
251 * Control reappears in this routine after the subsequent restore.
252 */
253static int create_image(int platform_mode)
254{
255 int error;
256
257 error = dpm_suspend_end(PMSG_FREEZE);
258 if (error) {
259 printk(KERN_ERR "PM: Some devices failed to power down, "
260 "aborting hibernation\n");
261 return error;
262 }
263
264 error = platform_pre_snapshot(platform_mode);
265 if (error || hibernation_test(TEST_PLATFORM))
266 goto Platform_finish;
267
268 error = disable_nonboot_cpus();
269 if (error || hibernation_test(TEST_CPUS))
270 goto Enable_cpus;
271
272 local_irq_disable();
273
274 error = syscore_suspend();
275 if (error) {
276 printk(KERN_ERR "PM: Some system devices failed to power down, "
277 "aborting hibernation\n");
278 goto Enable_irqs;
279 }
280
281 if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
282 goto Power_up;
283
284 in_suspend = 1;
285 save_processor_state();
286 error = swsusp_arch_suspend();
287 if (error)
288 printk(KERN_ERR "PM: Error %d creating hibernation image\n",
289 error);
290 /* Restore control flow magically appears here */
291 restore_processor_state();
292 if (!in_suspend) {
293 events_check_enabled = false;
294 platform_leave(platform_mode);
295 }
296
297 Power_up:
298 syscore_resume();
299
300 Enable_irqs:
301 local_irq_enable();
302
303 Enable_cpus:
304 enable_nonboot_cpus();
305
306 Platform_finish:
307 platform_finish(platform_mode);
308
309 dpm_resume_start(in_suspend ?
310 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
311
312 return error;
313}
314
315/**
316 * hibernation_snapshot - Quiesce devices and create a hibernation image.
317 * @platform_mode: If set, use platform driver to prepare for the transition.
318 *
319 * This routine must be called with pm_mutex held.
320 */
321int hibernation_snapshot(int platform_mode)
322{
323 pm_message_t msg;
324 int error;
325
326 error = platform_begin(platform_mode);
327 if (error)
328 goto Close;
329
330 /* Preallocate image memory before shutting down devices. */
331 error = hibernate_preallocate_memory();
332 if (error)
333 goto Close;
334
335 error = freeze_kernel_threads();
336 if (error)
337 goto Cleanup;
338
339 if (hibernation_test(TEST_FREEZER)) {
340
341 /*
342 * Indicate to the caller that we are returning due to a
343 * successful freezer test.
344 */
345 freezer_test_done = true;
346 goto Thaw;
347 }
348
349 error = dpm_prepare(PMSG_FREEZE);
350 if (error) {
351 dpm_complete(PMSG_RECOVER);
352 goto Thaw;
353 }
354
355 suspend_console();
356 ftrace_stop();
357 pm_restrict_gfp_mask();
358
359 error = dpm_suspend(PMSG_FREEZE);
360
361 if (error || hibernation_test(TEST_DEVICES))
362 platform_recover(platform_mode);
363 else
364 error = create_image(platform_mode);
365
366 /*
367 * In the case that we call create_image() above, the control
368 * returns here (1) after the image has been created or the
369 * image creation has failed and (2) after a successful restore.
370 */
371
372 /* We may need to release the preallocated image pages here. */
373 if (error || !in_suspend)
374 swsusp_free();
375
376 msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
377 dpm_resume(msg);
378
379 if (error || !in_suspend)
380 pm_restore_gfp_mask();
381
382 ftrace_start();
383 resume_console();
384 dpm_complete(msg);
385
386 Close:
387 platform_end(platform_mode);
388 return error;
389
390 Thaw:
391 thaw_kernel_threads();
392 Cleanup:
393 swsusp_free();
394 goto Close;
395}
396
397/**
398 * resume_target_kernel - Restore system state from a hibernation image.
399 * @platform_mode: Whether or not to use the platform driver.
400 *
401 * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
402 * contents of highmem that have not been restored yet from the image and run
403 * the low-level code that will restore the remaining contents of memory and
404 * switch to the just restored target kernel.
405 */
406static int resume_target_kernel(bool platform_mode)
407{
408 int error;
409
410 error = dpm_suspend_end(PMSG_QUIESCE);
411 if (error) {
412 printk(KERN_ERR "PM: Some devices failed to power down, "
413 "aborting resume\n");
414 return error;
415 }
416
417 error = platform_pre_restore(platform_mode);
418 if (error)
419 goto Cleanup;
420
421 error = disable_nonboot_cpus();
422 if (error)
423 goto Enable_cpus;
424
425 local_irq_disable();
426
427 error = syscore_suspend();
428 if (error)
429 goto Enable_irqs;
430
431 save_processor_state();
432 error = restore_highmem();
433 if (!error) {
434 error = swsusp_arch_resume();
435 /*
436 * The code below is only ever reached in case of a failure.
437 * Otherwise, execution continues at the place where
438 * swsusp_arch_suspend() was called.
439 */
440 BUG_ON(!error);
441 /*
442 * This call to restore_highmem() reverts the changes made by
443 * the previous one.
444 */
445 restore_highmem();
446 }
447 /*
448 * The only reason why swsusp_arch_resume() can fail is memory being
449 * very tight, so we have to free it as soon as we can to avoid
450 * subsequent failures.
451 */
452 swsusp_free();
453 restore_processor_state();
454 touch_softlockup_watchdog();
455
456 syscore_resume();
457
458 Enable_irqs:
459 local_irq_enable();
460
461 Enable_cpus:
462 enable_nonboot_cpus();
463
464 Cleanup:
465 platform_restore_cleanup(platform_mode);
466
467 dpm_resume_start(PMSG_RECOVER);
468
469 return error;
470}
471
472/**
473 * hibernation_restore - Quiesce devices and restore from a hibernation image.
474 * @platform_mode: If set, use platform driver to prepare for the transition.
475 *
476 * This routine must be called with pm_mutex held. If it is successful, control
477 * reappears in the restored target kernel in hibernation_snapshot().
478 */
479int hibernation_restore(int platform_mode)
480{
481 int error;
482
483 pm_prepare_console();
484 suspend_console();
485 ftrace_stop();
486 pm_restrict_gfp_mask();
487 error = dpm_suspend_start(PMSG_QUIESCE);
488 if (!error) {
489 error = resume_target_kernel(platform_mode);
490 dpm_resume_end(PMSG_RECOVER);
491 }
492 pm_restore_gfp_mask();
493 ftrace_start();
494 resume_console();
495 pm_restore_console();
496 return error;
497}
498
499/**
500 * hibernation_platform_enter - Power off the system using the platform driver.
501 */
502int hibernation_platform_enter(void)
503{
504 int error;
505
506 if (!hibernation_ops)
507 return -ENOSYS;
508
509 /*
510 * We have cancelled the power transition by running
511 * hibernation_ops->finish() before saving the image, so we should let
512 * the firmware know that we're going to enter the sleep state after all
513 */
514 error = hibernation_ops->begin();
515 if (error)
516 goto Close;
517
518 entering_platform_hibernation = true;
519 suspend_console();
520 ftrace_stop();
521 error = dpm_suspend_start(PMSG_HIBERNATE);
522 if (error) {
523 if (hibernation_ops->recover)
524 hibernation_ops->recover();
525 goto Resume_devices;
526 }
527
528 error = dpm_suspend_end(PMSG_HIBERNATE);
529 if (error)
530 goto Resume_devices;
531
532 error = hibernation_ops->prepare();
533 if (error)
534 goto Platform_finish;
535
536 error = disable_nonboot_cpus();
537 if (error)
538 goto Platform_finish;
539
540 local_irq_disable();
541 syscore_suspend();
542 if (pm_wakeup_pending()) {
543 error = -EAGAIN;
544 goto Power_up;
545 }
546
547 hibernation_ops->enter();
548 /* We should never get here */
549 while (1);
550
551 Power_up:
552 syscore_resume();
553 local_irq_enable();
554 enable_nonboot_cpus();
555
556 Platform_finish:
557 hibernation_ops->finish();
558
559 dpm_resume_start(PMSG_RESTORE);
560
561 Resume_devices:
562 entering_platform_hibernation = false;
563 dpm_resume_end(PMSG_RESTORE);
564 ftrace_start();
565 resume_console();
566
567 Close:
568 hibernation_ops->end();
569
570 return error;
571}
572
573/**
574 * power_down - Shut the machine down for hibernation.
575 *
576 * Use the platform driver, if configured, to put the system into the sleep
577 * state corresponding to hibernation, or try to power it off or reboot,
578 * depending on the value of hibernation_mode.
579 */
580static void power_down(void)
581{
582 switch (hibernation_mode) {
583 case HIBERNATION_REBOOT:
584 kernel_restart(NULL);
585 break;
586 case HIBERNATION_PLATFORM:
587 hibernation_platform_enter();
588 case HIBERNATION_SHUTDOWN:
589 kernel_power_off();
590 break;
591 }
592 kernel_halt();
593 /*
594 * Valid image is on the disk, if we continue we risk serious data
595 * corruption after resume.
596 */
597 printk(KERN_CRIT "PM: Please power down manually\n");
598 while(1);
599}
600
601/**
602 * hibernate - Carry out system hibernation, including saving the image.
603 */
604int hibernate(void)
605{
606 int error;
607
608 lock_system_sleep();
609 /* The snapshot device should not be opened while we're running */
610 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
611 error = -EBUSY;
612 goto Unlock;
613 }
614
615 pm_prepare_console();
616 error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
617 if (error)
618 goto Exit;
619
620 /* Allocate memory management structures */
621 error = create_basic_memory_bitmaps();
622 if (error)
623 goto Exit;
624
625 printk(KERN_INFO "PM: Syncing filesystems ... ");
626 sys_sync();
627 printk("done.\n");
628
629 error = freeze_processes();
630 if (error)
631 goto Free_bitmaps;
632
633 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
634 if (error || freezer_test_done)
635 goto Thaw;
636
637 if (in_suspend) {
638 unsigned int flags = 0;
639
640 if (hibernation_mode == HIBERNATION_PLATFORM)
641 flags |= SF_PLATFORM_MODE;
642 if (nocompress)
643 flags |= SF_NOCOMPRESS_MODE;
644 else
645 flags |= SF_CRC32_MODE;
646
647 pr_debug("PM: writing image.\n");
648 error = swsusp_write(flags);
649 swsusp_free();
650 if (!error)
651 power_down();
652 in_suspend = 0;
653 pm_restore_gfp_mask();
654 } else {
655 pr_debug("PM: Image restored successfully.\n");
656 }
657
658 Thaw:
659 thaw_processes();
660
661 /* Don't bother checking whether freezer_test_done is true */
662 freezer_test_done = false;
663
664 Free_bitmaps:
665 free_basic_memory_bitmaps();
666 Exit:
667 pm_notifier_call_chain(PM_POST_HIBERNATION);
668 pm_restore_console();
669 atomic_inc(&snapshot_device_available);
670 Unlock:
671 unlock_system_sleep();
672 return error;
673}
674
675
676/**
677 * software_resume - Resume from a saved hibernation image.
678 *
679 * This routine is called as a late initcall, when all devices have been
680 * discovered and initialized already.
681 *
682 * The image reading code is called to see if there is a hibernation image
683 * available for reading. If that is the case, devices are quiesced and the
684 * contents of memory is restored from the saved image.
685 *
686 * If this is successful, control reappears in the restored target kernel in
687 * hibernation_snaphot() which returns to hibernate(). Otherwise, the routine
688 * attempts to recover gracefully and make the kernel return to the normal mode
689 * of operation.
690 */
691static int software_resume(void)
692{
693 int error;
694 unsigned int flags;
695
696 /*
697 * If the user said "noresume".. bail out early.
698 */
699 if (noresume)
700 return 0;
701
702 /*
703 * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
704 * is configured into the kernel. Since the regular hibernate
705 * trigger path is via sysfs which takes a buffer mutex before
706 * calling hibernate functions (which take pm_mutex) this can
707 * cause lockdep to complain about a possible ABBA deadlock
708 * which cannot happen since we're in the boot code here and
709 * sysfs can't be invoked yet. Therefore, we use a subclass
710 * here to avoid lockdep complaining.
711 */
712 mutex_lock_nested(&pm_mutex, SINGLE_DEPTH_NESTING);
713
714 if (swsusp_resume_device)
715 goto Check_image;
716
717 if (!strlen(resume_file)) {
718 error = -ENOENT;
719 goto Unlock;
720 }
721
722 pr_debug("PM: Checking hibernation image partition %s\n", resume_file);
723
724 if (resume_delay) {
725 printk(KERN_INFO "Waiting %dsec before reading resume device...\n",
726 resume_delay);
727 ssleep(resume_delay);
728 }
729
730 /* Check if the device is there */
731 swsusp_resume_device = name_to_dev_t(resume_file);
732
733 /*
734 * name_to_dev_t is ineffective to verify parition if resume_file is in
735 * integer format. (e.g. major:minor)
736 */
737 if (isdigit(resume_file[0]) && resume_wait) {
738 int partno;
739 while (!get_gendisk(swsusp_resume_device, &partno))
740 msleep(10);
741 }
742
743 if (!swsusp_resume_device) {
744 /*
745 * Some device discovery might still be in progress; we need
746 * to wait for this to finish.
747 */
748 wait_for_device_probe();
749
750 if (resume_wait) {
751 while ((swsusp_resume_device = name_to_dev_t(resume_file)) == 0)
752 msleep(10);
753 async_synchronize_full();
754 }
755
756 swsusp_resume_device = name_to_dev_t(resume_file);
757 if (!swsusp_resume_device) {
758 error = -ENODEV;
759 goto Unlock;
760 }
761 }
762
763 Check_image:
764 pr_debug("PM: Hibernation image partition %d:%d present\n",
765 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
766
767 pr_debug("PM: Looking for hibernation image.\n");
768 error = swsusp_check();
769 if (error)
770 goto Unlock;
771
772 /* The snapshot device should not be opened while we're running */
773 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
774 error = -EBUSY;
775 swsusp_close(FMODE_READ);
776 goto Unlock;
777 }
778
779 pm_prepare_console();
780 error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
781 if (error)
782 goto close_finish;
783
784 error = create_basic_memory_bitmaps();
785 if (error)
786 goto close_finish;
787
788 pr_debug("PM: Preparing processes for restore.\n");
789 error = freeze_processes();
790 if (error) {
791 swsusp_close(FMODE_READ);
792 goto Done;
793 }
794
795 pr_debug("PM: Loading hibernation image.\n");
796
797 error = swsusp_read(&flags);
798 swsusp_close(FMODE_READ);
799 if (!error)
800 hibernation_restore(flags & SF_PLATFORM_MODE);
801
802 printk(KERN_ERR "PM: Failed to load hibernation image, recovering.\n");
803 swsusp_free();
804 thaw_processes();
805 Done:
806 free_basic_memory_bitmaps();
807 Finish:
808 pm_notifier_call_chain(PM_POST_RESTORE);
809 pm_restore_console();
810 atomic_inc(&snapshot_device_available);
811 /* For success case, the suspend path will release the lock */
812 Unlock:
813 mutex_unlock(&pm_mutex);
814 pr_debug("PM: Hibernation image not present or could not be loaded.\n");
815 return error;
816close_finish:
817 swsusp_close(FMODE_READ);
818 goto Finish;
819}
820
821late_initcall(software_resume);
822
823
824static const char * const hibernation_modes[] = {
825 [HIBERNATION_PLATFORM] = "platform",
826 [HIBERNATION_SHUTDOWN] = "shutdown",
827 [HIBERNATION_REBOOT] = "reboot",
828};
829
830/*
831 * /sys/power/disk - Control hibernation mode.
832 *
833 * Hibernation can be handled in several ways. There are a few different ways
834 * to put the system into the sleep state: using the platform driver (e.g. ACPI
835 * or other hibernation_ops), powering it off or rebooting it (for testing
836 * mostly).
837 *
838 * The sysfs file /sys/power/disk provides an interface for selecting the
839 * hibernation mode to use. Reading from this file causes the available modes
840 * to be printed. There are 3 modes that can be supported:
841 *
842 * 'platform'
843 * 'shutdown'
844 * 'reboot'
845 *
846 * If a platform hibernation driver is in use, 'platform' will be supported
847 * and will be used by default. Otherwise, 'shutdown' will be used by default.
848 * The selected option (i.e. the one corresponding to the current value of
849 * hibernation_mode) is enclosed by a square bracket.
850 *
851 * To select a given hibernation mode it is necessary to write the mode's
852 * string representation (as returned by reading from /sys/power/disk) back
853 * into /sys/power/disk.
854 */
855
856static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
857 char *buf)
858{
859 int i;
860 char *start = buf;
861
862 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
863 if (!hibernation_modes[i])
864 continue;
865 switch (i) {
866 case HIBERNATION_SHUTDOWN:
867 case HIBERNATION_REBOOT:
868 break;
869 case HIBERNATION_PLATFORM:
870 if (hibernation_ops)
871 break;
872 /* not a valid mode, continue with loop */
873 continue;
874 }
875 if (i == hibernation_mode)
876 buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
877 else
878 buf += sprintf(buf, "%s ", hibernation_modes[i]);
879 }
880 buf += sprintf(buf, "\n");
881 return buf-start;
882}
883
884static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
885 const char *buf, size_t n)
886{
887 int error = 0;
888 int i;
889 int len;
890 char *p;
891 int mode = HIBERNATION_INVALID;
892
893 p = memchr(buf, '\n', n);
894 len = p ? p - buf : n;
895
896 lock_system_sleep();
897 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
898 if (len == strlen(hibernation_modes[i])
899 && !strncmp(buf, hibernation_modes[i], len)) {
900 mode = i;
901 break;
902 }
903 }
904 if (mode != HIBERNATION_INVALID) {
905 switch (mode) {
906 case HIBERNATION_SHUTDOWN:
907 case HIBERNATION_REBOOT:
908 hibernation_mode = mode;
909 break;
910 case HIBERNATION_PLATFORM:
911 if (hibernation_ops)
912 hibernation_mode = mode;
913 else
914 error = -EINVAL;
915 }
916 } else
917 error = -EINVAL;
918
919 if (!error)
920 pr_debug("PM: Hibernation mode set to '%s'\n",
921 hibernation_modes[mode]);
922 unlock_system_sleep();
923 return error ? error : n;
924}
925
926power_attr(disk);
927
928static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
929 char *buf)
930{
931 return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
932 MINOR(swsusp_resume_device));
933}
934
935static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
936 const char *buf, size_t n)
937{
938 unsigned int maj, min;
939 dev_t res;
940 int ret = -EINVAL;
941
942 if (sscanf(buf, "%u:%u", &maj, &min) != 2)
943 goto out;
944
945 res = MKDEV(maj,min);
946 if (maj != MAJOR(res) || min != MINOR(res))
947 goto out;
948
949 lock_system_sleep();
950 swsusp_resume_device = res;
951 unlock_system_sleep();
952 printk(KERN_INFO "PM: Starting manual resume from disk\n");
953 noresume = 0;
954 software_resume();
955 ret = n;
956 out:
957 return ret;
958}
959
960power_attr(resume);
961
962static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
963 char *buf)
964{
965 return sprintf(buf, "%lu\n", image_size);
966}
967
968static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
969 const char *buf, size_t n)
970{
971 unsigned long size;
972
973 if (sscanf(buf, "%lu", &size) == 1) {
974 image_size = size;
975 return n;
976 }
977
978 return -EINVAL;
979}
980
981power_attr(image_size);
982
983static ssize_t reserved_size_show(struct kobject *kobj,
984 struct kobj_attribute *attr, char *buf)
985{
986 return sprintf(buf, "%lu\n", reserved_size);
987}
988
989static ssize_t reserved_size_store(struct kobject *kobj,
990 struct kobj_attribute *attr,
991 const char *buf, size_t n)
992{
993 unsigned long size;
994
995 if (sscanf(buf, "%lu", &size) == 1) {
996 reserved_size = size;
997 return n;
998 }
999
1000 return -EINVAL;
1001}
1002
1003power_attr(reserved_size);
1004
1005static struct attribute * g[] = {
1006 &disk_attr.attr,
1007 &resume_attr.attr,
1008 &image_size_attr.attr,
1009 &reserved_size_attr.attr,
1010 NULL,
1011};
1012
1013
1014static struct attribute_group attr_group = {
1015 .attrs = g,
1016};
1017
1018
1019static int __init pm_disk_init(void)
1020{
1021 return sysfs_create_group(power_kobj, &attr_group);
1022}
1023
1024core_initcall(pm_disk_init);
1025
1026
1027static int __init resume_setup(char *str)
1028{
1029 if (noresume)
1030 return 1;
1031
1032 strncpy( resume_file, str, 255 );
1033 return 1;
1034}
1035
1036static int __init resume_offset_setup(char *str)
1037{
1038 unsigned long long offset;
1039
1040 if (noresume)
1041 return 1;
1042
1043 if (sscanf(str, "%llu", &offset) == 1)
1044 swsusp_resume_block = offset;
1045
1046 return 1;
1047}
1048
1049static int __init hibernate_setup(char *str)
1050{
1051 if (!strncmp(str, "noresume", 8))
1052 noresume = 1;
1053 else if (!strncmp(str, "nocompress", 10))
1054 nocompress = 1;
1055 return 1;
1056}
1057
1058static int __init noresume_setup(char *str)
1059{
1060 noresume = 1;
1061 return 1;
1062}
1063
1064static int __init resumewait_setup(char *str)
1065{
1066 resume_wait = 1;
1067 return 1;
1068}
1069
1070static int __init resumedelay_setup(char *str)
1071{
1072 resume_delay = simple_strtoul(str, NULL, 0);
1073 return 1;
1074}
1075
1076__setup("noresume", noresume_setup);
1077__setup("resume_offset=", resume_offset_setup);
1078__setup("resume=", resume_setup);
1079__setup("hibernate=", hibernate_setup);
1080__setup("resumewait", resumewait_setup);
1081__setup("resumedelay=", resumedelay_setup);