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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 * Copyright (C) 2012 Bojan Smojver <bojan@rexursive.com>
9 *
10 * This file is released under the GPLv2.
11 */
12
13#include <linux/export.h>
14#include <linux/suspend.h>
15#include <linux/syscalls.h>
16#include <linux/reboot.h>
17#include <linux/string.h>
18#include <linux/device.h>
19#include <linux/async.h>
20#include <linux/delay.h>
21#include <linux/fs.h>
22#include <linux/mount.h>
23#include <linux/pm.h>
24#include <linux/console.h>
25#include <linux/cpu.h>
26#include <linux/freezer.h>
27#include <linux/gfp.h>
28#include <linux/syscore_ops.h>
29#include <linux/ctype.h>
30#include <linux/genhd.h>
31
32#include "power.h"
33
34
35static int nocompress;
36static int noresume;
37static int resume_wait;
38static int resume_delay;
39static char resume_file[256] = CONFIG_PM_STD_PARTITION;
40dev_t swsusp_resume_device;
41sector_t swsusp_resume_block;
42__visible int in_suspend __nosavedata;
43
44enum {
45 HIBERNATION_INVALID,
46 HIBERNATION_PLATFORM,
47 HIBERNATION_SHUTDOWN,
48 HIBERNATION_REBOOT,
49#ifdef CONFIG_SUSPEND
50 HIBERNATION_SUSPEND,
51#endif
52 /* keep last */
53 __HIBERNATION_AFTER_LAST
54};
55#define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
56#define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
57
58static int hibernation_mode = HIBERNATION_SHUTDOWN;
59
60bool freezer_test_done;
61
62static const struct platform_hibernation_ops *hibernation_ops;
63
64/**
65 * hibernation_set_ops - Set the global hibernate operations.
66 * @ops: Hibernation operations to use in subsequent hibernation transitions.
67 */
68void hibernation_set_ops(const struct platform_hibernation_ops *ops)
69{
70 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
71 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
72 && ops->restore_cleanup && ops->leave)) {
73 WARN_ON(1);
74 return;
75 }
76 lock_system_sleep();
77 hibernation_ops = ops;
78 if (ops)
79 hibernation_mode = HIBERNATION_PLATFORM;
80 else if (hibernation_mode == HIBERNATION_PLATFORM)
81 hibernation_mode = HIBERNATION_SHUTDOWN;
82
83 unlock_system_sleep();
84}
85EXPORT_SYMBOL_GPL(hibernation_set_ops);
86
87static bool entering_platform_hibernation;
88
89bool system_entering_hibernation(void)
90{
91 return entering_platform_hibernation;
92}
93EXPORT_SYMBOL(system_entering_hibernation);
94
95#ifdef CONFIG_PM_DEBUG
96static void hibernation_debug_sleep(void)
97{
98 printk(KERN_INFO "hibernation debug: Waiting for 5 seconds.\n");
99 mdelay(5000);
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_test(int level) { return 0; }
112#endif /* !CONFIG_PM_DEBUG */
113
114/**
115 * platform_begin - Call platform to start hibernation.
116 * @platform_mode: Whether or not to use the platform driver.
117 */
118static int platform_begin(int platform_mode)
119{
120 return (platform_mode && hibernation_ops) ?
121 hibernation_ops->begin() : 0;
122}
123
124/**
125 * platform_end - Call platform to finish transition to the working state.
126 * @platform_mode: Whether or not to use the platform driver.
127 */
128static void platform_end(int platform_mode)
129{
130 if (platform_mode && hibernation_ops)
131 hibernation_ops->end();
132}
133
134/**
135 * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
136 * @platform_mode: Whether or not to use the platform driver.
137 *
138 * Use the platform driver to prepare the system for creating a hibernate image,
139 * if so configured, and return an error code if that fails.
140 */
141
142static int platform_pre_snapshot(int platform_mode)
143{
144 return (platform_mode && hibernation_ops) ?
145 hibernation_ops->pre_snapshot() : 0;
146}
147
148/**
149 * platform_leave - Call platform to prepare a transition to the working state.
150 * @platform_mode: Whether or not to use the platform driver.
151 *
152 * Use the platform driver prepare to prepare the machine for switching to the
153 * normal mode of operation.
154 *
155 * This routine is called on one CPU with interrupts disabled.
156 */
157static void platform_leave(int platform_mode)
158{
159 if (platform_mode && hibernation_ops)
160 hibernation_ops->leave();
161}
162
163/**
164 * platform_finish - Call platform to switch the system to the working state.
165 * @platform_mode: Whether or not to use the platform driver.
166 *
167 * Use the platform driver to switch the machine to the normal mode of
168 * operation.
169 *
170 * This routine must be called after platform_prepare().
171 */
172static void platform_finish(int platform_mode)
173{
174 if (platform_mode && hibernation_ops)
175 hibernation_ops->finish();
176}
177
178/**
179 * platform_pre_restore - Prepare for hibernate image restoration.
180 * @platform_mode: Whether or not to use the platform driver.
181 *
182 * Use the platform driver to prepare the system for resume from a hibernation
183 * image.
184 *
185 * If the restore fails after this function has been called,
186 * platform_restore_cleanup() must be called.
187 */
188static int platform_pre_restore(int platform_mode)
189{
190 return (platform_mode && hibernation_ops) ?
191 hibernation_ops->pre_restore() : 0;
192}
193
194/**
195 * platform_restore_cleanup - Switch to the working state after failing restore.
196 * @platform_mode: Whether or not to use the platform driver.
197 *
198 * Use the platform driver to switch the system to the normal mode of operation
199 * after a failing restore.
200 *
201 * If platform_pre_restore() has been called before the failing restore, this
202 * function must be called too, regardless of the result of
203 * platform_pre_restore().
204 */
205static void platform_restore_cleanup(int platform_mode)
206{
207 if (platform_mode && hibernation_ops)
208 hibernation_ops->restore_cleanup();
209}
210
211/**
212 * platform_recover - Recover from a failure to suspend devices.
213 * @platform_mode: Whether or not to use the platform driver.
214 */
215static void platform_recover(int platform_mode)
216{
217 if (platform_mode && hibernation_ops && hibernation_ops->recover)
218 hibernation_ops->recover();
219}
220
221/**
222 * swsusp_show_speed - Print time elapsed between two events during hibernation.
223 * @start: Starting event.
224 * @stop: Final event.
225 * @nr_pages: Number of memory pages processed between @start and @stop.
226 * @msg: Additional diagnostic message to print.
227 */
228void swsusp_show_speed(struct timeval *start, struct timeval *stop,
229 unsigned nr_pages, char *msg)
230{
231 s64 elapsed_centisecs64;
232 int centisecs;
233 int k;
234 int kps;
235
236 elapsed_centisecs64 = timeval_to_ns(stop) - timeval_to_ns(start);
237 do_div(elapsed_centisecs64, NSEC_PER_SEC / 100);
238 centisecs = elapsed_centisecs64;
239 if (centisecs == 0)
240 centisecs = 1; /* avoid div-by-zero */
241 k = nr_pages * (PAGE_SIZE / 1024);
242 kps = (k * 100) / centisecs;
243 printk(KERN_INFO "PM: %s %d kbytes in %d.%02d seconds (%d.%02d MB/s)\n",
244 msg, k,
245 centisecs / 100, centisecs % 100,
246 kps / 1000, (kps % 1000) / 10);
247}
248
249/**
250 * create_image - Create a hibernation image.
251 * @platform_mode: Whether or not to use the platform driver.
252 *
253 * Execute device drivers' "late" and "noirq" freeze callbacks, create a
254 * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
255 *
256 * Control reappears in this routine after the subsequent restore.
257 */
258static int create_image(int platform_mode)
259{
260 int error;
261
262 error = dpm_suspend_end(PMSG_FREEZE);
263 if (error) {
264 printk(KERN_ERR "PM: Some devices failed to power down, "
265 "aborting hibernation\n");
266 return error;
267 }
268
269 error = platform_pre_snapshot(platform_mode);
270 if (error || hibernation_test(TEST_PLATFORM))
271 goto Platform_finish;
272
273 error = disable_nonboot_cpus();
274 if (error || hibernation_test(TEST_CPUS))
275 goto Enable_cpus;
276
277 local_irq_disable();
278
279 error = syscore_suspend();
280 if (error) {
281 printk(KERN_ERR "PM: Some system devices failed to power down, "
282 "aborting hibernation\n");
283 goto Enable_irqs;
284 }
285
286 if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
287 goto Power_up;
288
289 in_suspend = 1;
290 save_processor_state();
291 error = swsusp_arch_suspend();
292 if (error)
293 printk(KERN_ERR "PM: Error %d creating hibernation image\n",
294 error);
295 /* Restore control flow magically appears here */
296 restore_processor_state();
297 if (!in_suspend)
298 events_check_enabled = false;
299
300 platform_leave(platform_mode);
301
302 Power_up:
303 syscore_resume();
304
305 Enable_irqs:
306 local_irq_enable();
307
308 Enable_cpus:
309 enable_nonboot_cpus();
310
311 Platform_finish:
312 platform_finish(platform_mode);
313
314 dpm_resume_start(in_suspend ?
315 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
316
317 return error;
318}
319
320/**
321 * hibernation_snapshot - Quiesce devices and create a hibernation image.
322 * @platform_mode: If set, use platform driver to prepare for the transition.
323 *
324 * This routine must be called with pm_mutex held.
325 */
326int hibernation_snapshot(int platform_mode)
327{
328 pm_message_t msg;
329 int error;
330
331 error = platform_begin(platform_mode);
332 if (error)
333 goto Close;
334
335 /* Preallocate image memory before shutting down devices. */
336 error = hibernate_preallocate_memory();
337 if (error)
338 goto Close;
339
340 error = freeze_kernel_threads();
341 if (error)
342 goto Cleanup;
343
344 if (hibernation_test(TEST_FREEZER)) {
345
346 /*
347 * Indicate to the caller that we are returning due to a
348 * successful freezer test.
349 */
350 freezer_test_done = true;
351 goto Thaw;
352 }
353
354 error = dpm_prepare(PMSG_FREEZE);
355 if (error) {
356 dpm_complete(PMSG_RECOVER);
357 goto Thaw;
358 }
359
360 suspend_console();
361 ftrace_stop();
362 pm_restrict_gfp_mask();
363
364 error = dpm_suspend(PMSG_FREEZE);
365
366 if (error || hibernation_test(TEST_DEVICES))
367 platform_recover(platform_mode);
368 else
369 error = create_image(platform_mode);
370
371 /*
372 * In the case that we call create_image() above, the control
373 * returns here (1) after the image has been created or the
374 * image creation has failed and (2) after a successful restore.
375 */
376
377 /* We may need to release the preallocated image pages here. */
378 if (error || !in_suspend)
379 swsusp_free();
380
381 msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
382 dpm_resume(msg);
383
384 if (error || !in_suspend)
385 pm_restore_gfp_mask();
386
387 ftrace_start();
388 resume_console();
389 dpm_complete(msg);
390
391 Close:
392 platform_end(platform_mode);
393 return error;
394
395 Thaw:
396 thaw_kernel_threads();
397 Cleanup:
398 swsusp_free();
399 goto Close;
400}
401
402/**
403 * resume_target_kernel - Restore system state from a hibernation image.
404 * @platform_mode: Whether or not to use the platform driver.
405 *
406 * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
407 * contents of highmem that have not been restored yet from the image and run
408 * the low-level code that will restore the remaining contents of memory and
409 * switch to the just restored target kernel.
410 */
411static int resume_target_kernel(bool platform_mode)
412{
413 int error;
414
415 error = dpm_suspend_end(PMSG_QUIESCE);
416 if (error) {
417 printk(KERN_ERR "PM: Some devices failed to power down, "
418 "aborting resume\n");
419 return error;
420 }
421
422 error = platform_pre_restore(platform_mode);
423 if (error)
424 goto Cleanup;
425
426 error = disable_nonboot_cpus();
427 if (error)
428 goto Enable_cpus;
429
430 local_irq_disable();
431
432 error = syscore_suspend();
433 if (error)
434 goto Enable_irqs;
435
436 save_processor_state();
437 error = restore_highmem();
438 if (!error) {
439 error = swsusp_arch_resume();
440 /*
441 * The code below is only ever reached in case of a failure.
442 * Otherwise, execution continues at the place where
443 * swsusp_arch_suspend() was called.
444 */
445 BUG_ON(!error);
446 /*
447 * This call to restore_highmem() reverts the changes made by
448 * the previous one.
449 */
450 restore_highmem();
451 }
452 /*
453 * The only reason why swsusp_arch_resume() can fail is memory being
454 * very tight, so we have to free it as soon as we can to avoid
455 * subsequent failures.
456 */
457 swsusp_free();
458 restore_processor_state();
459 touch_softlockup_watchdog();
460
461 syscore_resume();
462
463 Enable_irqs:
464 local_irq_enable();
465
466 Enable_cpus:
467 enable_nonboot_cpus();
468
469 Cleanup:
470 platform_restore_cleanup(platform_mode);
471
472 dpm_resume_start(PMSG_RECOVER);
473
474 return error;
475}
476
477/**
478 * hibernation_restore - Quiesce devices and restore from a hibernation image.
479 * @platform_mode: If set, use platform driver to prepare for the transition.
480 *
481 * This routine must be called with pm_mutex held. If it is successful, control
482 * reappears in the restored target kernel in hibernation_snapshot().
483 */
484int hibernation_restore(int platform_mode)
485{
486 int error;
487
488 pm_prepare_console();
489 suspend_console();
490 ftrace_stop();
491 pm_restrict_gfp_mask();
492 error = dpm_suspend_start(PMSG_QUIESCE);
493 if (!error) {
494 error = resume_target_kernel(platform_mode);
495 dpm_resume_end(PMSG_RECOVER);
496 }
497 pm_restore_gfp_mask();
498 ftrace_start();
499 resume_console();
500 pm_restore_console();
501 return error;
502}
503
504/**
505 * hibernation_platform_enter - Power off the system using the platform driver.
506 */
507int hibernation_platform_enter(void)
508{
509 int error;
510
511 if (!hibernation_ops)
512 return -ENOSYS;
513
514 /*
515 * We have cancelled the power transition by running
516 * hibernation_ops->finish() before saving the image, so we should let
517 * the firmware know that we're going to enter the sleep state after all
518 */
519 error = hibernation_ops->begin();
520 if (error)
521 goto Close;
522
523 entering_platform_hibernation = true;
524 suspend_console();
525 ftrace_stop();
526 error = dpm_suspend_start(PMSG_HIBERNATE);
527 if (error) {
528 if (hibernation_ops->recover)
529 hibernation_ops->recover();
530 goto Resume_devices;
531 }
532
533 error = dpm_suspend_end(PMSG_HIBERNATE);
534 if (error)
535 goto Resume_devices;
536
537 error = hibernation_ops->prepare();
538 if (error)
539 goto Platform_finish;
540
541 error = disable_nonboot_cpus();
542 if (error)
543 goto Platform_finish;
544
545 local_irq_disable();
546 syscore_suspend();
547 if (pm_wakeup_pending()) {
548 error = -EAGAIN;
549 goto Power_up;
550 }
551
552 hibernation_ops->enter();
553 /* We should never get here */
554 while (1);
555
556 Power_up:
557 syscore_resume();
558 local_irq_enable();
559 enable_nonboot_cpus();
560
561 Platform_finish:
562 hibernation_ops->finish();
563
564 dpm_resume_start(PMSG_RESTORE);
565
566 Resume_devices:
567 entering_platform_hibernation = false;
568 dpm_resume_end(PMSG_RESTORE);
569 ftrace_start();
570 resume_console();
571
572 Close:
573 hibernation_ops->end();
574
575 return error;
576}
577
578/**
579 * power_down - Shut the machine down for hibernation.
580 *
581 * Use the platform driver, if configured, to put the system into the sleep
582 * state corresponding to hibernation, or try to power it off or reboot,
583 * depending on the value of hibernation_mode.
584 */
585static void power_down(void)
586{
587#ifdef CONFIG_SUSPEND
588 int error;
589#endif
590
591 switch (hibernation_mode) {
592 case HIBERNATION_REBOOT:
593 kernel_restart(NULL);
594 break;
595 case HIBERNATION_PLATFORM:
596 hibernation_platform_enter();
597 case HIBERNATION_SHUTDOWN:
598 kernel_power_off();
599 break;
600#ifdef CONFIG_SUSPEND
601 case HIBERNATION_SUSPEND:
602 error = suspend_devices_and_enter(PM_SUSPEND_MEM);
603 if (error) {
604 if (hibernation_ops)
605 hibernation_mode = HIBERNATION_PLATFORM;
606 else
607 hibernation_mode = HIBERNATION_SHUTDOWN;
608 power_down();
609 }
610 /*
611 * Restore swap signature.
612 */
613 error = swsusp_unmark();
614 if (error)
615 printk(KERN_ERR "PM: Swap will be unusable! "
616 "Try swapon -a.\n");
617 return;
618#endif
619 }
620 kernel_halt();
621 /*
622 * Valid image is on the disk, if we continue we risk serious data
623 * corruption after resume.
624 */
625 printk(KERN_CRIT "PM: Please power down manually\n");
626 while(1);
627}
628
629/**
630 * hibernate - Carry out system hibernation, including saving the image.
631 */
632int hibernate(void)
633{
634 int error;
635
636 lock_system_sleep();
637 /* The snapshot device should not be opened while we're running */
638 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
639 error = -EBUSY;
640 goto Unlock;
641 }
642
643 pm_prepare_console();
644 error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
645 if (error)
646 goto Exit;
647
648 printk(KERN_INFO "PM: Syncing filesystems ... ");
649 sys_sync();
650 printk("done.\n");
651
652 error = freeze_processes();
653 if (error)
654 goto Exit;
655
656 lock_device_hotplug();
657 /* Allocate memory management structures */
658 error = create_basic_memory_bitmaps();
659 if (error)
660 goto Thaw;
661
662 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
663 if (error || freezer_test_done)
664 goto Free_bitmaps;
665
666 if (in_suspend) {
667 unsigned int flags = 0;
668
669 if (hibernation_mode == HIBERNATION_PLATFORM)
670 flags |= SF_PLATFORM_MODE;
671 if (nocompress)
672 flags |= SF_NOCOMPRESS_MODE;
673 else
674 flags |= SF_CRC32_MODE;
675
676 pr_debug("PM: writing image.\n");
677 error = swsusp_write(flags);
678 swsusp_free();
679 if (!error)
680 power_down();
681 in_suspend = 0;
682 pm_restore_gfp_mask();
683 } else {
684 pr_debug("PM: Image restored successfully.\n");
685 }
686
687 Free_bitmaps:
688 free_basic_memory_bitmaps();
689 Thaw:
690 unlock_device_hotplug();
691 thaw_processes();
692
693 /* Don't bother checking whether freezer_test_done is true */
694 freezer_test_done = false;
695 Exit:
696 pm_notifier_call_chain(PM_POST_HIBERNATION);
697 pm_restore_console();
698 atomic_inc(&snapshot_device_available);
699 Unlock:
700 unlock_system_sleep();
701 return error;
702}
703
704
705/**
706 * software_resume - Resume from a saved hibernation image.
707 *
708 * This routine is called as a late initcall, when all devices have been
709 * discovered and initialized already.
710 *
711 * The image reading code is called to see if there is a hibernation image
712 * available for reading. If that is the case, devices are quiesced and the
713 * contents of memory is restored from the saved image.
714 *
715 * If this is successful, control reappears in the restored target kernel in
716 * hibernation_snaphot() which returns to hibernate(). Otherwise, the routine
717 * attempts to recover gracefully and make the kernel return to the normal mode
718 * of operation.
719 */
720static int software_resume(void)
721{
722 int error;
723 unsigned int flags;
724
725 /*
726 * If the user said "noresume".. bail out early.
727 */
728 if (noresume)
729 return 0;
730
731 /*
732 * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
733 * is configured into the kernel. Since the regular hibernate
734 * trigger path is via sysfs which takes a buffer mutex before
735 * calling hibernate functions (which take pm_mutex) this can
736 * cause lockdep to complain about a possible ABBA deadlock
737 * which cannot happen since we're in the boot code here and
738 * sysfs can't be invoked yet. Therefore, we use a subclass
739 * here to avoid lockdep complaining.
740 */
741 mutex_lock_nested(&pm_mutex, SINGLE_DEPTH_NESTING);
742
743 if (swsusp_resume_device)
744 goto Check_image;
745
746 if (!strlen(resume_file)) {
747 error = -ENOENT;
748 goto Unlock;
749 }
750
751 pr_debug("PM: Checking hibernation image partition %s\n", resume_file);
752
753 if (resume_delay) {
754 printk(KERN_INFO "Waiting %dsec before reading resume device...\n",
755 resume_delay);
756 ssleep(resume_delay);
757 }
758
759 /* Check if the device is there */
760 swsusp_resume_device = name_to_dev_t(resume_file);
761
762 /*
763 * name_to_dev_t is ineffective to verify parition if resume_file is in
764 * integer format. (e.g. major:minor)
765 */
766 if (isdigit(resume_file[0]) && resume_wait) {
767 int partno;
768 while (!get_gendisk(swsusp_resume_device, &partno))
769 msleep(10);
770 }
771
772 if (!swsusp_resume_device) {
773 /*
774 * Some device discovery might still be in progress; we need
775 * to wait for this to finish.
776 */
777 wait_for_device_probe();
778
779 if (resume_wait) {
780 while ((swsusp_resume_device = name_to_dev_t(resume_file)) == 0)
781 msleep(10);
782 async_synchronize_full();
783 }
784
785 swsusp_resume_device = name_to_dev_t(resume_file);
786 if (!swsusp_resume_device) {
787 error = -ENODEV;
788 goto Unlock;
789 }
790 }
791
792 Check_image:
793 pr_debug("PM: Hibernation image partition %d:%d present\n",
794 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
795
796 pr_debug("PM: Looking for hibernation image.\n");
797 error = swsusp_check();
798 if (error)
799 goto Unlock;
800
801 /* The snapshot device should not be opened while we're running */
802 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
803 error = -EBUSY;
804 swsusp_close(FMODE_READ);
805 goto Unlock;
806 }
807
808 pm_prepare_console();
809 error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
810 if (error)
811 goto Close_Finish;
812
813 pr_debug("PM: Preparing processes for restore.\n");
814 error = freeze_processes();
815 if (error)
816 goto Close_Finish;
817
818 pr_debug("PM: Loading hibernation image.\n");
819
820 lock_device_hotplug();
821 error = create_basic_memory_bitmaps();
822 if (error)
823 goto Thaw;
824
825 error = swsusp_read(&flags);
826 swsusp_close(FMODE_READ);
827 if (!error)
828 hibernation_restore(flags & SF_PLATFORM_MODE);
829
830 printk(KERN_ERR "PM: Failed to load hibernation image, recovering.\n");
831 swsusp_free();
832 free_basic_memory_bitmaps();
833 Thaw:
834 unlock_device_hotplug();
835 thaw_processes();
836 Finish:
837 pm_notifier_call_chain(PM_POST_RESTORE);
838 pm_restore_console();
839 atomic_inc(&snapshot_device_available);
840 /* For success case, the suspend path will release the lock */
841 Unlock:
842 mutex_unlock(&pm_mutex);
843 pr_debug("PM: Hibernation image not present or could not be loaded.\n");
844 return error;
845 Close_Finish:
846 swsusp_close(FMODE_READ);
847 goto Finish;
848}
849
850late_initcall_sync(software_resume);
851
852
853static const char * const hibernation_modes[] = {
854 [HIBERNATION_PLATFORM] = "platform",
855 [HIBERNATION_SHUTDOWN] = "shutdown",
856 [HIBERNATION_REBOOT] = "reboot",
857#ifdef CONFIG_SUSPEND
858 [HIBERNATION_SUSPEND] = "suspend",
859#endif
860};
861
862/*
863 * /sys/power/disk - Control hibernation mode.
864 *
865 * Hibernation can be handled in several ways. There are a few different ways
866 * to put the system into the sleep state: using the platform driver (e.g. ACPI
867 * or other hibernation_ops), powering it off or rebooting it (for testing
868 * mostly).
869 *
870 * The sysfs file /sys/power/disk provides an interface for selecting the
871 * hibernation mode to use. Reading from this file causes the available modes
872 * to be printed. There are 3 modes that can be supported:
873 *
874 * 'platform'
875 * 'shutdown'
876 * 'reboot'
877 *
878 * If a platform hibernation driver is in use, 'platform' will be supported
879 * and will be used by default. Otherwise, 'shutdown' will be used by default.
880 * The selected option (i.e. the one corresponding to the current value of
881 * hibernation_mode) is enclosed by a square bracket.
882 *
883 * To select a given hibernation mode it is necessary to write the mode's
884 * string representation (as returned by reading from /sys/power/disk) back
885 * into /sys/power/disk.
886 */
887
888static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
889 char *buf)
890{
891 int i;
892 char *start = buf;
893
894 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
895 if (!hibernation_modes[i])
896 continue;
897 switch (i) {
898 case HIBERNATION_SHUTDOWN:
899 case HIBERNATION_REBOOT:
900#ifdef CONFIG_SUSPEND
901 case HIBERNATION_SUSPEND:
902#endif
903 break;
904 case HIBERNATION_PLATFORM:
905 if (hibernation_ops)
906 break;
907 /* not a valid mode, continue with loop */
908 continue;
909 }
910 if (i == hibernation_mode)
911 buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
912 else
913 buf += sprintf(buf, "%s ", hibernation_modes[i]);
914 }
915 buf += sprintf(buf, "\n");
916 return buf-start;
917}
918
919static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
920 const char *buf, size_t n)
921{
922 int error = 0;
923 int i;
924 int len;
925 char *p;
926 int mode = HIBERNATION_INVALID;
927
928 p = memchr(buf, '\n', n);
929 len = p ? p - buf : n;
930
931 lock_system_sleep();
932 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
933 if (len == strlen(hibernation_modes[i])
934 && !strncmp(buf, hibernation_modes[i], len)) {
935 mode = i;
936 break;
937 }
938 }
939 if (mode != HIBERNATION_INVALID) {
940 switch (mode) {
941 case HIBERNATION_SHUTDOWN:
942 case HIBERNATION_REBOOT:
943#ifdef CONFIG_SUSPEND
944 case HIBERNATION_SUSPEND:
945#endif
946 hibernation_mode = mode;
947 break;
948 case HIBERNATION_PLATFORM:
949 if (hibernation_ops)
950 hibernation_mode = mode;
951 else
952 error = -EINVAL;
953 }
954 } else
955 error = -EINVAL;
956
957 if (!error)
958 pr_debug("PM: Hibernation mode set to '%s'\n",
959 hibernation_modes[mode]);
960 unlock_system_sleep();
961 return error ? error : n;
962}
963
964power_attr(disk);
965
966static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
967 char *buf)
968{
969 return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
970 MINOR(swsusp_resume_device));
971}
972
973static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
974 const char *buf, size_t n)
975{
976 dev_t res;
977 int len = n;
978 char *name;
979
980 if (len && buf[len-1] == '\n')
981 len--;
982 name = kstrndup(buf, len, GFP_KERNEL);
983 if (!name)
984 return -ENOMEM;
985
986 res = name_to_dev_t(name);
987 kfree(name);
988 if (!res)
989 return -EINVAL;
990
991 lock_system_sleep();
992 swsusp_resume_device = res;
993 unlock_system_sleep();
994 printk(KERN_INFO "PM: Starting manual resume from disk\n");
995 noresume = 0;
996 software_resume();
997 return n;
998}
999
1000power_attr(resume);
1001
1002static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
1003 char *buf)
1004{
1005 return sprintf(buf, "%lu\n", image_size);
1006}
1007
1008static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
1009 const char *buf, size_t n)
1010{
1011 unsigned long size;
1012
1013 if (sscanf(buf, "%lu", &size) == 1) {
1014 image_size = size;
1015 return n;
1016 }
1017
1018 return -EINVAL;
1019}
1020
1021power_attr(image_size);
1022
1023static ssize_t reserved_size_show(struct kobject *kobj,
1024 struct kobj_attribute *attr, char *buf)
1025{
1026 return sprintf(buf, "%lu\n", reserved_size);
1027}
1028
1029static ssize_t reserved_size_store(struct kobject *kobj,
1030 struct kobj_attribute *attr,
1031 const char *buf, size_t n)
1032{
1033 unsigned long size;
1034
1035 if (sscanf(buf, "%lu", &size) == 1) {
1036 reserved_size = size;
1037 return n;
1038 }
1039
1040 return -EINVAL;
1041}
1042
1043power_attr(reserved_size);
1044
1045static struct attribute * g[] = {
1046 &disk_attr.attr,
1047 &resume_attr.attr,
1048 &image_size_attr.attr,
1049 &reserved_size_attr.attr,
1050 NULL,
1051};
1052
1053
1054static struct attribute_group attr_group = {
1055 .attrs = g,
1056};
1057
1058
1059static int __init pm_disk_init(void)
1060{
1061 return sysfs_create_group(power_kobj, &attr_group);
1062}
1063
1064core_initcall(pm_disk_init);
1065
1066
1067static int __init resume_setup(char *str)
1068{
1069 if (noresume)
1070 return 1;
1071
1072 strncpy( resume_file, str, 255 );
1073 return 1;
1074}
1075
1076static int __init resume_offset_setup(char *str)
1077{
1078 unsigned long long offset;
1079
1080 if (noresume)
1081 return 1;
1082
1083 if (sscanf(str, "%llu", &offset) == 1)
1084 swsusp_resume_block = offset;
1085
1086 return 1;
1087}
1088
1089static int __init hibernate_setup(char *str)
1090{
1091 if (!strncmp(str, "noresume", 8))
1092 noresume = 1;
1093 else if (!strncmp(str, "nocompress", 10))
1094 nocompress = 1;
1095 return 1;
1096}
1097
1098static int __init noresume_setup(char *str)
1099{
1100 noresume = 1;
1101 return 1;
1102}
1103
1104static int __init resumewait_setup(char *str)
1105{
1106 resume_wait = 1;
1107 return 1;
1108}
1109
1110static int __init resumedelay_setup(char *str)
1111{
1112 resume_delay = simple_strtoul(str, NULL, 0);
1113 return 1;
1114}
1115
1116__setup("noresume", noresume_setup);
1117__setup("resume_offset=", resume_offset_setup);
1118__setup("resume=", resume_setup);
1119__setup("hibernate=", hibernate_setup);
1120__setup("resumewait", resumewait_setup);
1121__setup("resumedelay=", resumedelay_setup);