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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/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);
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);