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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * kernel/power/hibernate.c - Hibernation (a.k.a suspend-to-disk) support.
4 *
5 * Copyright (c) 2003 Patrick Mochel
6 * Copyright (c) 2003 Open Source Development Lab
7 * Copyright (c) 2004 Pavel Machek <pavel@ucw.cz>
8 * Copyright (c) 2009 Rafael J. Wysocki, Novell Inc.
9 * Copyright (C) 2012 Bojan Smojver <bojan@rexursive.com>
10 */
11
12#define pr_fmt(fmt) "PM: hibernation: " fmt
13
14#include <linux/export.h>
15#include <linux/suspend.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/nmi.h>
25#include <linux/console.h>
26#include <linux/cpu.h>
27#include <linux/freezer.h>
28#include <linux/gfp.h>
29#include <linux/syscore_ops.h>
30#include <linux/ctype.h>
31#include <linux/ktime.h>
32#include <linux/security.h>
33#include <linux/secretmem.h>
34#include <trace/events/power.h>
35
36#include "power.h"
37
38
39static int nocompress;
40static int noresume;
41static int nohibernate;
42static int resume_wait;
43static unsigned int resume_delay;
44static char resume_file[256] = CONFIG_PM_STD_PARTITION;
45dev_t swsusp_resume_device;
46sector_t swsusp_resume_block;
47__visible int in_suspend __nosavedata;
48
49enum {
50 HIBERNATION_INVALID,
51 HIBERNATION_PLATFORM,
52 HIBERNATION_SHUTDOWN,
53 HIBERNATION_REBOOT,
54#ifdef CONFIG_SUSPEND
55 HIBERNATION_SUSPEND,
56#endif
57 HIBERNATION_TEST_RESUME,
58 /* keep last */
59 __HIBERNATION_AFTER_LAST
60};
61#define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
62#define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
63
64static int hibernation_mode = HIBERNATION_SHUTDOWN;
65
66bool freezer_test_done;
67
68static const struct platform_hibernation_ops *hibernation_ops;
69
70static atomic_t hibernate_atomic = ATOMIC_INIT(1);
71
72bool hibernate_acquire(void)
73{
74 return atomic_add_unless(&hibernate_atomic, -1, 0);
75}
76
77void hibernate_release(void)
78{
79 atomic_inc(&hibernate_atomic);
80}
81
82bool hibernation_available(void)
83{
84 return nohibernate == 0 &&
85 !security_locked_down(LOCKDOWN_HIBERNATION) &&
86 !secretmem_active() && !cxl_mem_active();
87}
88
89/**
90 * hibernation_set_ops - Set the global hibernate operations.
91 * @ops: Hibernation operations to use in subsequent hibernation transitions.
92 */
93void hibernation_set_ops(const struct platform_hibernation_ops *ops)
94{
95 unsigned int sleep_flags;
96
97 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
98 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
99 && ops->restore_cleanup && ops->leave)) {
100 WARN_ON(1);
101 return;
102 }
103
104 sleep_flags = lock_system_sleep();
105
106 hibernation_ops = ops;
107 if (ops)
108 hibernation_mode = HIBERNATION_PLATFORM;
109 else if (hibernation_mode == HIBERNATION_PLATFORM)
110 hibernation_mode = HIBERNATION_SHUTDOWN;
111
112 unlock_system_sleep(sleep_flags);
113}
114EXPORT_SYMBOL_GPL(hibernation_set_ops);
115
116static bool entering_platform_hibernation;
117
118bool system_entering_hibernation(void)
119{
120 return entering_platform_hibernation;
121}
122EXPORT_SYMBOL(system_entering_hibernation);
123
124#ifdef CONFIG_PM_DEBUG
125static void hibernation_debug_sleep(void)
126{
127 pr_info("debug: Waiting for 5 seconds.\n");
128 mdelay(5000);
129}
130
131static int hibernation_test(int level)
132{
133 if (pm_test_level == level) {
134 hibernation_debug_sleep();
135 return 1;
136 }
137 return 0;
138}
139#else /* !CONFIG_PM_DEBUG */
140static int hibernation_test(int level) { return 0; }
141#endif /* !CONFIG_PM_DEBUG */
142
143/**
144 * platform_begin - Call platform to start hibernation.
145 * @platform_mode: Whether or not to use the platform driver.
146 */
147static int platform_begin(int platform_mode)
148{
149 return (platform_mode && hibernation_ops) ?
150 hibernation_ops->begin(PMSG_FREEZE) : 0;
151}
152
153/**
154 * platform_end - Call platform to finish transition to the working state.
155 * @platform_mode: Whether or not to use the platform driver.
156 */
157static void platform_end(int platform_mode)
158{
159 if (platform_mode && hibernation_ops)
160 hibernation_ops->end();
161}
162
163/**
164 * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
165 * @platform_mode: Whether or not to use the platform driver.
166 *
167 * Use the platform driver to prepare the system for creating a hibernate image,
168 * if so configured, and return an error code if that fails.
169 */
170
171static int platform_pre_snapshot(int platform_mode)
172{
173 return (platform_mode && hibernation_ops) ?
174 hibernation_ops->pre_snapshot() : 0;
175}
176
177/**
178 * platform_leave - Call platform to prepare a transition to the working state.
179 * @platform_mode: Whether or not to use the platform driver.
180 *
181 * Use the platform driver prepare to prepare the machine for switching to the
182 * normal mode of operation.
183 *
184 * This routine is called on one CPU with interrupts disabled.
185 */
186static void platform_leave(int platform_mode)
187{
188 if (platform_mode && hibernation_ops)
189 hibernation_ops->leave();
190}
191
192/**
193 * platform_finish - Call platform to switch the system to the working state.
194 * @platform_mode: Whether or not to use the platform driver.
195 *
196 * Use the platform driver to switch the machine to the normal mode of
197 * operation.
198 *
199 * This routine must be called after platform_prepare().
200 */
201static void platform_finish(int platform_mode)
202{
203 if (platform_mode && hibernation_ops)
204 hibernation_ops->finish();
205}
206
207/**
208 * platform_pre_restore - Prepare for hibernate image restoration.
209 * @platform_mode: Whether or not to use the platform driver.
210 *
211 * Use the platform driver to prepare the system for resume from a hibernation
212 * image.
213 *
214 * If the restore fails after this function has been called,
215 * platform_restore_cleanup() must be called.
216 */
217static int platform_pre_restore(int platform_mode)
218{
219 return (platform_mode && hibernation_ops) ?
220 hibernation_ops->pre_restore() : 0;
221}
222
223/**
224 * platform_restore_cleanup - Switch to the working state after failing restore.
225 * @platform_mode: Whether or not to use the platform driver.
226 *
227 * Use the platform driver to switch the system to the normal mode of operation
228 * after a failing restore.
229 *
230 * If platform_pre_restore() has been called before the failing restore, this
231 * function must be called too, regardless of the result of
232 * platform_pre_restore().
233 */
234static void platform_restore_cleanup(int platform_mode)
235{
236 if (platform_mode && hibernation_ops)
237 hibernation_ops->restore_cleanup();
238}
239
240/**
241 * platform_recover - Recover from a failure to suspend devices.
242 * @platform_mode: Whether or not to use the platform driver.
243 */
244static void platform_recover(int platform_mode)
245{
246 if (platform_mode && hibernation_ops && hibernation_ops->recover)
247 hibernation_ops->recover();
248}
249
250/**
251 * swsusp_show_speed - Print time elapsed between two events during hibernation.
252 * @start: Starting event.
253 * @stop: Final event.
254 * @nr_pages: Number of memory pages processed between @start and @stop.
255 * @msg: Additional diagnostic message to print.
256 */
257void swsusp_show_speed(ktime_t start, ktime_t stop,
258 unsigned nr_pages, char *msg)
259{
260 ktime_t diff;
261 u64 elapsed_centisecs64;
262 unsigned int centisecs;
263 unsigned int k;
264 unsigned int kps;
265
266 diff = ktime_sub(stop, start);
267 elapsed_centisecs64 = ktime_divns(diff, 10*NSEC_PER_MSEC);
268 centisecs = elapsed_centisecs64;
269 if (centisecs == 0)
270 centisecs = 1; /* avoid div-by-zero */
271 k = nr_pages * (PAGE_SIZE / 1024);
272 kps = (k * 100) / centisecs;
273 pr_info("%s %u kbytes in %u.%02u seconds (%u.%02u MB/s)\n",
274 msg, k, centisecs / 100, centisecs % 100, kps / 1000,
275 (kps % 1000) / 10);
276}
277
278__weak int arch_resume_nosmt(void)
279{
280 return 0;
281}
282
283/**
284 * create_image - Create a hibernation image.
285 * @platform_mode: Whether or not to use the platform driver.
286 *
287 * Execute device drivers' "late" and "noirq" freeze callbacks, create a
288 * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
289 *
290 * Control reappears in this routine after the subsequent restore.
291 */
292static int create_image(int platform_mode)
293{
294 int error;
295
296 error = dpm_suspend_end(PMSG_FREEZE);
297 if (error) {
298 pr_err("Some devices failed to power down, aborting\n");
299 return error;
300 }
301
302 error = platform_pre_snapshot(platform_mode);
303 if (error || hibernation_test(TEST_PLATFORM))
304 goto Platform_finish;
305
306 error = pm_sleep_disable_secondary_cpus();
307 if (error || hibernation_test(TEST_CPUS))
308 goto Enable_cpus;
309
310 local_irq_disable();
311
312 system_state = SYSTEM_SUSPEND;
313
314 error = syscore_suspend();
315 if (error) {
316 pr_err("Some system devices failed to power down, aborting\n");
317 goto Enable_irqs;
318 }
319
320 if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
321 goto Power_up;
322
323 in_suspend = 1;
324 save_processor_state();
325 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true);
326 error = swsusp_arch_suspend();
327 /* Restore control flow magically appears here */
328 restore_processor_state();
329 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false);
330 if (error)
331 pr_err("Error %d creating image\n", error);
332
333 if (!in_suspend) {
334 events_check_enabled = false;
335 clear_or_poison_free_pages();
336 }
337
338 platform_leave(platform_mode);
339
340 Power_up:
341 syscore_resume();
342
343 Enable_irqs:
344 system_state = SYSTEM_RUNNING;
345 local_irq_enable();
346
347 Enable_cpus:
348 pm_sleep_enable_secondary_cpus();
349
350 /* Allow architectures to do nosmt-specific post-resume dances */
351 if (!in_suspend)
352 error = arch_resume_nosmt();
353
354 Platform_finish:
355 platform_finish(platform_mode);
356
357 dpm_resume_start(in_suspend ?
358 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
359
360 return error;
361}
362
363/**
364 * hibernation_snapshot - Quiesce devices and create a hibernation image.
365 * @platform_mode: If set, use platform driver to prepare for the transition.
366 *
367 * This routine must be called with system_transition_mutex held.
368 */
369int hibernation_snapshot(int platform_mode)
370{
371 pm_message_t msg;
372 int error;
373
374 pm_suspend_clear_flags();
375 error = platform_begin(platform_mode);
376 if (error)
377 goto Close;
378
379 /* Preallocate image memory before shutting down devices. */
380 error = hibernate_preallocate_memory();
381 if (error)
382 goto Close;
383
384 error = freeze_kernel_threads();
385 if (error)
386 goto Cleanup;
387
388 if (hibernation_test(TEST_FREEZER)) {
389
390 /*
391 * Indicate to the caller that we are returning due to a
392 * successful freezer test.
393 */
394 freezer_test_done = true;
395 goto Thaw;
396 }
397
398 error = dpm_prepare(PMSG_FREEZE);
399 if (error) {
400 dpm_complete(PMSG_RECOVER);
401 goto Thaw;
402 }
403
404 suspend_console();
405 pm_restrict_gfp_mask();
406
407 error = dpm_suspend(PMSG_FREEZE);
408
409 if (error || hibernation_test(TEST_DEVICES))
410 platform_recover(platform_mode);
411 else
412 error = create_image(platform_mode);
413
414 /*
415 * In the case that we call create_image() above, the control
416 * returns here (1) after the image has been created or the
417 * image creation has failed and (2) after a successful restore.
418 */
419
420 /* We may need to release the preallocated image pages here. */
421 if (error || !in_suspend)
422 swsusp_free();
423
424 msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
425 dpm_resume(msg);
426
427 if (error || !in_suspend)
428 pm_restore_gfp_mask();
429
430 resume_console();
431 dpm_complete(msg);
432
433 Close:
434 platform_end(platform_mode);
435 return error;
436
437 Thaw:
438 thaw_kernel_threads();
439 Cleanup:
440 swsusp_free();
441 goto Close;
442}
443
444int __weak hibernate_resume_nonboot_cpu_disable(void)
445{
446 return suspend_disable_secondary_cpus();
447}
448
449/**
450 * resume_target_kernel - Restore system state from a hibernation image.
451 * @platform_mode: Whether or not to use the platform driver.
452 *
453 * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
454 * contents of highmem that have not been restored yet from the image and run
455 * the low-level code that will restore the remaining contents of memory and
456 * switch to the just restored target kernel.
457 */
458static int resume_target_kernel(bool platform_mode)
459{
460 int error;
461
462 error = dpm_suspend_end(PMSG_QUIESCE);
463 if (error) {
464 pr_err("Some devices failed to power down, aborting resume\n");
465 return error;
466 }
467
468 error = platform_pre_restore(platform_mode);
469 if (error)
470 goto Cleanup;
471
472 cpuidle_pause();
473
474 error = hibernate_resume_nonboot_cpu_disable();
475 if (error)
476 goto Enable_cpus;
477
478 local_irq_disable();
479 system_state = SYSTEM_SUSPEND;
480
481 error = syscore_suspend();
482 if (error)
483 goto Enable_irqs;
484
485 save_processor_state();
486 error = restore_highmem();
487 if (!error) {
488 error = swsusp_arch_resume();
489 /*
490 * The code below is only ever reached in case of a failure.
491 * Otherwise, execution continues at the place where
492 * swsusp_arch_suspend() was called.
493 */
494 BUG_ON(!error);
495 /*
496 * This call to restore_highmem() reverts the changes made by
497 * the previous one.
498 */
499 restore_highmem();
500 }
501 /*
502 * The only reason why swsusp_arch_resume() can fail is memory being
503 * very tight, so we have to free it as soon as we can to avoid
504 * subsequent failures.
505 */
506 swsusp_free();
507 restore_processor_state();
508 touch_softlockup_watchdog();
509
510 syscore_resume();
511
512 Enable_irqs:
513 system_state = SYSTEM_RUNNING;
514 local_irq_enable();
515
516 Enable_cpus:
517 pm_sleep_enable_secondary_cpus();
518
519 Cleanup:
520 platform_restore_cleanup(platform_mode);
521
522 dpm_resume_start(PMSG_RECOVER);
523
524 return error;
525}
526
527/**
528 * hibernation_restore - Quiesce devices and restore from a hibernation image.
529 * @platform_mode: If set, use platform driver to prepare for the transition.
530 *
531 * This routine must be called with system_transition_mutex held. If it is
532 * successful, control reappears in the restored target kernel in
533 * hibernation_snapshot().
534 */
535int hibernation_restore(int platform_mode)
536{
537 int error;
538
539 pm_prepare_console();
540 suspend_console();
541 pm_restrict_gfp_mask();
542 error = dpm_suspend_start(PMSG_QUIESCE);
543 if (!error) {
544 error = resume_target_kernel(platform_mode);
545 /*
546 * The above should either succeed and jump to the new kernel,
547 * or return with an error. Otherwise things are just
548 * undefined, so let's be paranoid.
549 */
550 BUG_ON(!error);
551 }
552 dpm_resume_end(PMSG_RECOVER);
553 pm_restore_gfp_mask();
554 resume_console();
555 pm_restore_console();
556 return error;
557}
558
559/**
560 * hibernation_platform_enter - Power off the system using the platform driver.
561 */
562int hibernation_platform_enter(void)
563{
564 int error;
565
566 if (!hibernation_ops)
567 return -ENOSYS;
568
569 /*
570 * We have cancelled the power transition by running
571 * hibernation_ops->finish() before saving the image, so we should let
572 * the firmware know that we're going to enter the sleep state after all
573 */
574 error = hibernation_ops->begin(PMSG_HIBERNATE);
575 if (error)
576 goto Close;
577
578 entering_platform_hibernation = true;
579 suspend_console();
580 error = dpm_suspend_start(PMSG_HIBERNATE);
581 if (error) {
582 if (hibernation_ops->recover)
583 hibernation_ops->recover();
584 goto Resume_devices;
585 }
586
587 error = dpm_suspend_end(PMSG_HIBERNATE);
588 if (error)
589 goto Resume_devices;
590
591 error = hibernation_ops->prepare();
592 if (error)
593 goto Platform_finish;
594
595 error = pm_sleep_disable_secondary_cpus();
596 if (error)
597 goto Enable_cpus;
598
599 local_irq_disable();
600 system_state = SYSTEM_SUSPEND;
601 syscore_suspend();
602 if (pm_wakeup_pending()) {
603 error = -EAGAIN;
604 goto Power_up;
605 }
606
607 hibernation_ops->enter();
608 /* We should never get here */
609 while (1);
610
611 Power_up:
612 syscore_resume();
613 system_state = SYSTEM_RUNNING;
614 local_irq_enable();
615
616 Enable_cpus:
617 pm_sleep_enable_secondary_cpus();
618
619 Platform_finish:
620 hibernation_ops->finish();
621
622 dpm_resume_start(PMSG_RESTORE);
623
624 Resume_devices:
625 entering_platform_hibernation = false;
626 dpm_resume_end(PMSG_RESTORE);
627 resume_console();
628
629 Close:
630 hibernation_ops->end();
631
632 return error;
633}
634
635/**
636 * power_down - Shut the machine down for hibernation.
637 *
638 * Use the platform driver, if configured, to put the system into the sleep
639 * state corresponding to hibernation, or try to power it off or reboot,
640 * depending on the value of hibernation_mode.
641 */
642static void power_down(void)
643{
644#ifdef CONFIG_SUSPEND
645 int error;
646
647 if (hibernation_mode == HIBERNATION_SUSPEND) {
648 error = suspend_devices_and_enter(mem_sleep_current);
649 if (error) {
650 hibernation_mode = hibernation_ops ?
651 HIBERNATION_PLATFORM :
652 HIBERNATION_SHUTDOWN;
653 } else {
654 /* Restore swap signature. */
655 error = swsusp_unmark();
656 if (error)
657 pr_err("Swap will be unusable! Try swapon -a.\n");
658
659 return;
660 }
661 }
662#endif
663
664 switch (hibernation_mode) {
665 case HIBERNATION_REBOOT:
666 kernel_restart(NULL);
667 break;
668 case HIBERNATION_PLATFORM:
669 hibernation_platform_enter();
670 fallthrough;
671 case HIBERNATION_SHUTDOWN:
672 if (kernel_can_power_off())
673 kernel_power_off();
674 break;
675 }
676 kernel_halt();
677 /*
678 * Valid image is on the disk, if we continue we risk serious data
679 * corruption after resume.
680 */
681 pr_crit("Power down manually\n");
682 while (1)
683 cpu_relax();
684}
685
686static int load_image_and_restore(void)
687{
688 int error;
689 unsigned int flags;
690
691 pm_pr_dbg("Loading hibernation image.\n");
692
693 lock_device_hotplug();
694 error = create_basic_memory_bitmaps();
695 if (error) {
696 swsusp_close(FMODE_READ | FMODE_EXCL);
697 goto Unlock;
698 }
699
700 error = swsusp_read(&flags);
701 swsusp_close(FMODE_READ | FMODE_EXCL);
702 if (!error)
703 error = hibernation_restore(flags & SF_PLATFORM_MODE);
704
705 pr_err("Failed to load image, recovering.\n");
706 swsusp_free();
707 free_basic_memory_bitmaps();
708 Unlock:
709 unlock_device_hotplug();
710
711 return error;
712}
713
714/**
715 * hibernate - Carry out system hibernation, including saving the image.
716 */
717int hibernate(void)
718{
719 bool snapshot_test = false;
720 unsigned int sleep_flags;
721 int error;
722
723 if (!hibernation_available()) {
724 pm_pr_dbg("Hibernation not available.\n");
725 return -EPERM;
726 }
727
728 sleep_flags = lock_system_sleep();
729 /* The snapshot device should not be opened while we're running */
730 if (!hibernate_acquire()) {
731 error = -EBUSY;
732 goto Unlock;
733 }
734
735 pr_info("hibernation entry\n");
736 pm_prepare_console();
737 error = pm_notifier_call_chain_robust(PM_HIBERNATION_PREPARE, PM_POST_HIBERNATION);
738 if (error)
739 goto Restore;
740
741 ksys_sync_helper();
742
743 error = freeze_processes();
744 if (error)
745 goto Exit;
746
747 lock_device_hotplug();
748 /* Allocate memory management structures */
749 error = create_basic_memory_bitmaps();
750 if (error)
751 goto Thaw;
752
753 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
754 if (error || freezer_test_done)
755 goto Free_bitmaps;
756
757 if (in_suspend) {
758 unsigned int flags = 0;
759
760 if (hibernation_mode == HIBERNATION_PLATFORM)
761 flags |= SF_PLATFORM_MODE;
762 if (nocompress)
763 flags |= SF_NOCOMPRESS_MODE;
764 else
765 flags |= SF_CRC32_MODE;
766
767 pm_pr_dbg("Writing hibernation image.\n");
768 error = swsusp_write(flags);
769 swsusp_free();
770 if (!error) {
771 if (hibernation_mode == HIBERNATION_TEST_RESUME)
772 snapshot_test = true;
773 else
774 power_down();
775 }
776 in_suspend = 0;
777 pm_restore_gfp_mask();
778 } else {
779 pm_pr_dbg("Hibernation image restored successfully.\n");
780 }
781
782 Free_bitmaps:
783 free_basic_memory_bitmaps();
784 Thaw:
785 unlock_device_hotplug();
786 if (snapshot_test) {
787 pm_pr_dbg("Checking hibernation image\n");
788 error = swsusp_check();
789 if (!error)
790 error = load_image_and_restore();
791 }
792 thaw_processes();
793
794 /* Don't bother checking whether freezer_test_done is true */
795 freezer_test_done = false;
796 Exit:
797 pm_notifier_call_chain(PM_POST_HIBERNATION);
798 Restore:
799 pm_restore_console();
800 hibernate_release();
801 Unlock:
802 unlock_system_sleep(sleep_flags);
803 pr_info("hibernation exit\n");
804
805 return error;
806}
807
808/**
809 * hibernate_quiet_exec - Execute a function with all devices frozen.
810 * @func: Function to execute.
811 * @data: Data pointer to pass to @func.
812 *
813 * Return the @func return value or an error code if it cannot be executed.
814 */
815int hibernate_quiet_exec(int (*func)(void *data), void *data)
816{
817 unsigned int sleep_flags;
818 int error;
819
820 sleep_flags = lock_system_sleep();
821
822 if (!hibernate_acquire()) {
823 error = -EBUSY;
824 goto unlock;
825 }
826
827 pm_prepare_console();
828
829 error = pm_notifier_call_chain_robust(PM_HIBERNATION_PREPARE, PM_POST_HIBERNATION);
830 if (error)
831 goto restore;
832
833 error = freeze_processes();
834 if (error)
835 goto exit;
836
837 lock_device_hotplug();
838
839 pm_suspend_clear_flags();
840
841 error = platform_begin(true);
842 if (error)
843 goto thaw;
844
845 error = freeze_kernel_threads();
846 if (error)
847 goto thaw;
848
849 error = dpm_prepare(PMSG_FREEZE);
850 if (error)
851 goto dpm_complete;
852
853 suspend_console();
854
855 error = dpm_suspend(PMSG_FREEZE);
856 if (error)
857 goto dpm_resume;
858
859 error = dpm_suspend_end(PMSG_FREEZE);
860 if (error)
861 goto dpm_resume;
862
863 error = platform_pre_snapshot(true);
864 if (error)
865 goto skip;
866
867 error = func(data);
868
869skip:
870 platform_finish(true);
871
872 dpm_resume_start(PMSG_THAW);
873
874dpm_resume:
875 dpm_resume(PMSG_THAW);
876
877 resume_console();
878
879dpm_complete:
880 dpm_complete(PMSG_THAW);
881
882 thaw_kernel_threads();
883
884thaw:
885 platform_end(true);
886
887 unlock_device_hotplug();
888
889 thaw_processes();
890
891exit:
892 pm_notifier_call_chain(PM_POST_HIBERNATION);
893
894restore:
895 pm_restore_console();
896
897 hibernate_release();
898
899unlock:
900 unlock_system_sleep(sleep_flags);
901
902 return error;
903}
904EXPORT_SYMBOL_GPL(hibernate_quiet_exec);
905
906/**
907 * software_resume - Resume from a saved hibernation image.
908 *
909 * This routine is called as a late initcall, when all devices have been
910 * discovered and initialized already.
911 *
912 * The image reading code is called to see if there is a hibernation image
913 * available for reading. If that is the case, devices are quiesced and the
914 * contents of memory is restored from the saved image.
915 *
916 * If this is successful, control reappears in the restored target kernel in
917 * hibernation_snapshot() which returns to hibernate(). Otherwise, the routine
918 * attempts to recover gracefully and make the kernel return to the normal mode
919 * of operation.
920 */
921static int software_resume(void)
922{
923 int error;
924
925 /*
926 * If the user said "noresume".. bail out early.
927 */
928 if (noresume || !hibernation_available())
929 return 0;
930
931 /*
932 * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
933 * is configured into the kernel. Since the regular hibernate
934 * trigger path is via sysfs which takes a buffer mutex before
935 * calling hibernate functions (which take system_transition_mutex)
936 * this can cause lockdep to complain about a possible ABBA deadlock
937 * which cannot happen since we're in the boot code here and
938 * sysfs can't be invoked yet. Therefore, we use a subclass
939 * here to avoid lockdep complaining.
940 */
941 mutex_lock_nested(&system_transition_mutex, SINGLE_DEPTH_NESTING);
942
943 if (swsusp_resume_device)
944 goto Check_image;
945
946 if (!strlen(resume_file)) {
947 error = -ENOENT;
948 goto Unlock;
949 }
950
951 pm_pr_dbg("Checking hibernation image partition %s\n", resume_file);
952
953 if (resume_delay) {
954 pr_info("Waiting %dsec before reading resume device ...\n",
955 resume_delay);
956 ssleep(resume_delay);
957 }
958
959 /* Check if the device is there */
960 swsusp_resume_device = name_to_dev_t(resume_file);
961 if (!swsusp_resume_device) {
962 /*
963 * Some device discovery might still be in progress; we need
964 * to wait for this to finish.
965 */
966 wait_for_device_probe();
967
968 if (resume_wait) {
969 while ((swsusp_resume_device = name_to_dev_t(resume_file)) == 0)
970 msleep(10);
971 async_synchronize_full();
972 }
973
974 swsusp_resume_device = name_to_dev_t(resume_file);
975 if (!swsusp_resume_device) {
976 error = -ENODEV;
977 goto Unlock;
978 }
979 }
980
981 Check_image:
982 pm_pr_dbg("Hibernation image partition %d:%d present\n",
983 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
984
985 pm_pr_dbg("Looking for hibernation image.\n");
986 error = swsusp_check();
987 if (error)
988 goto Unlock;
989
990 /* The snapshot device should not be opened while we're running */
991 if (!hibernate_acquire()) {
992 error = -EBUSY;
993 swsusp_close(FMODE_READ | FMODE_EXCL);
994 goto Unlock;
995 }
996
997 pr_info("resume from hibernation\n");
998 pm_prepare_console();
999 error = pm_notifier_call_chain_robust(PM_RESTORE_PREPARE, PM_POST_RESTORE);
1000 if (error)
1001 goto Restore;
1002
1003 pm_pr_dbg("Preparing processes for hibernation restore.\n");
1004 error = freeze_processes();
1005 if (error)
1006 goto Close_Finish;
1007
1008 error = freeze_kernel_threads();
1009 if (error) {
1010 thaw_processes();
1011 goto Close_Finish;
1012 }
1013
1014 error = load_image_and_restore();
1015 thaw_processes();
1016 Finish:
1017 pm_notifier_call_chain(PM_POST_RESTORE);
1018 Restore:
1019 pm_restore_console();
1020 pr_info("resume failed (%d)\n", error);
1021 hibernate_release();
1022 /* For success case, the suspend path will release the lock */
1023 Unlock:
1024 mutex_unlock(&system_transition_mutex);
1025 pm_pr_dbg("Hibernation image not present or could not be loaded.\n");
1026 return error;
1027 Close_Finish:
1028 swsusp_close(FMODE_READ | FMODE_EXCL);
1029 goto Finish;
1030}
1031
1032late_initcall_sync(software_resume);
1033
1034
1035static const char * const hibernation_modes[] = {
1036 [HIBERNATION_PLATFORM] = "platform",
1037 [HIBERNATION_SHUTDOWN] = "shutdown",
1038 [HIBERNATION_REBOOT] = "reboot",
1039#ifdef CONFIG_SUSPEND
1040 [HIBERNATION_SUSPEND] = "suspend",
1041#endif
1042 [HIBERNATION_TEST_RESUME] = "test_resume",
1043};
1044
1045/*
1046 * /sys/power/disk - Control hibernation mode.
1047 *
1048 * Hibernation can be handled in several ways. There are a few different ways
1049 * to put the system into the sleep state: using the platform driver (e.g. ACPI
1050 * or other hibernation_ops), powering it off or rebooting it (for testing
1051 * mostly).
1052 *
1053 * The sysfs file /sys/power/disk provides an interface for selecting the
1054 * hibernation mode to use. Reading from this file causes the available modes
1055 * to be printed. There are 3 modes that can be supported:
1056 *
1057 * 'platform'
1058 * 'shutdown'
1059 * 'reboot'
1060 *
1061 * If a platform hibernation driver is in use, 'platform' will be supported
1062 * and will be used by default. Otherwise, 'shutdown' will be used by default.
1063 * The selected option (i.e. the one corresponding to the current value of
1064 * hibernation_mode) is enclosed by a square bracket.
1065 *
1066 * To select a given hibernation mode it is necessary to write the mode's
1067 * string representation (as returned by reading from /sys/power/disk) back
1068 * into /sys/power/disk.
1069 */
1070
1071static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
1072 char *buf)
1073{
1074 int i;
1075 char *start = buf;
1076
1077 if (!hibernation_available())
1078 return sprintf(buf, "[disabled]\n");
1079
1080 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
1081 if (!hibernation_modes[i])
1082 continue;
1083 switch (i) {
1084 case HIBERNATION_SHUTDOWN:
1085 case HIBERNATION_REBOOT:
1086#ifdef CONFIG_SUSPEND
1087 case HIBERNATION_SUSPEND:
1088#endif
1089 case HIBERNATION_TEST_RESUME:
1090 break;
1091 case HIBERNATION_PLATFORM:
1092 if (hibernation_ops)
1093 break;
1094 /* not a valid mode, continue with loop */
1095 continue;
1096 }
1097 if (i == hibernation_mode)
1098 buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
1099 else
1100 buf += sprintf(buf, "%s ", hibernation_modes[i]);
1101 }
1102 buf += sprintf(buf, "\n");
1103 return buf-start;
1104}
1105
1106static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
1107 const char *buf, size_t n)
1108{
1109 int mode = HIBERNATION_INVALID;
1110 unsigned int sleep_flags;
1111 int error = 0;
1112 int len;
1113 char *p;
1114 int i;
1115
1116 if (!hibernation_available())
1117 return -EPERM;
1118
1119 p = memchr(buf, '\n', n);
1120 len = p ? p - buf : n;
1121
1122 sleep_flags = lock_system_sleep();
1123 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
1124 if (len == strlen(hibernation_modes[i])
1125 && !strncmp(buf, hibernation_modes[i], len)) {
1126 mode = i;
1127 break;
1128 }
1129 }
1130 if (mode != HIBERNATION_INVALID) {
1131 switch (mode) {
1132 case HIBERNATION_SHUTDOWN:
1133 case HIBERNATION_REBOOT:
1134#ifdef CONFIG_SUSPEND
1135 case HIBERNATION_SUSPEND:
1136#endif
1137 case HIBERNATION_TEST_RESUME:
1138 hibernation_mode = mode;
1139 break;
1140 case HIBERNATION_PLATFORM:
1141 if (hibernation_ops)
1142 hibernation_mode = mode;
1143 else
1144 error = -EINVAL;
1145 }
1146 } else
1147 error = -EINVAL;
1148
1149 if (!error)
1150 pm_pr_dbg("Hibernation mode set to '%s'\n",
1151 hibernation_modes[mode]);
1152 unlock_system_sleep(sleep_flags);
1153 return error ? error : n;
1154}
1155
1156power_attr(disk);
1157
1158static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
1159 char *buf)
1160{
1161 return sprintf(buf, "%d:%d\n", MAJOR(swsusp_resume_device),
1162 MINOR(swsusp_resume_device));
1163}
1164
1165static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
1166 const char *buf, size_t n)
1167{
1168 unsigned int sleep_flags;
1169 int len = n;
1170 char *name;
1171 dev_t res;
1172
1173 if (len && buf[len-1] == '\n')
1174 len--;
1175 name = kstrndup(buf, len, GFP_KERNEL);
1176 if (!name)
1177 return -ENOMEM;
1178
1179 res = name_to_dev_t(name);
1180 kfree(name);
1181 if (!res)
1182 return -EINVAL;
1183
1184 sleep_flags = lock_system_sleep();
1185 swsusp_resume_device = res;
1186 unlock_system_sleep(sleep_flags);
1187
1188 pm_pr_dbg("Configured hibernation resume from disk to %u\n",
1189 swsusp_resume_device);
1190 noresume = 0;
1191 software_resume();
1192 return n;
1193}
1194
1195power_attr(resume);
1196
1197static ssize_t resume_offset_show(struct kobject *kobj,
1198 struct kobj_attribute *attr, char *buf)
1199{
1200 return sprintf(buf, "%llu\n", (unsigned long long)swsusp_resume_block);
1201}
1202
1203static ssize_t resume_offset_store(struct kobject *kobj,
1204 struct kobj_attribute *attr, const char *buf,
1205 size_t n)
1206{
1207 unsigned long long offset;
1208 int rc;
1209
1210 rc = kstrtoull(buf, 0, &offset);
1211 if (rc)
1212 return rc;
1213 swsusp_resume_block = offset;
1214
1215 return n;
1216}
1217
1218power_attr(resume_offset);
1219
1220static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
1221 char *buf)
1222{
1223 return sprintf(buf, "%lu\n", image_size);
1224}
1225
1226static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
1227 const char *buf, size_t n)
1228{
1229 unsigned long size;
1230
1231 if (sscanf(buf, "%lu", &size) == 1) {
1232 image_size = size;
1233 return n;
1234 }
1235
1236 return -EINVAL;
1237}
1238
1239power_attr(image_size);
1240
1241static ssize_t reserved_size_show(struct kobject *kobj,
1242 struct kobj_attribute *attr, char *buf)
1243{
1244 return sprintf(buf, "%lu\n", reserved_size);
1245}
1246
1247static ssize_t reserved_size_store(struct kobject *kobj,
1248 struct kobj_attribute *attr,
1249 const char *buf, size_t n)
1250{
1251 unsigned long size;
1252
1253 if (sscanf(buf, "%lu", &size) == 1) {
1254 reserved_size = size;
1255 return n;
1256 }
1257
1258 return -EINVAL;
1259}
1260
1261power_attr(reserved_size);
1262
1263static struct attribute *g[] = {
1264 &disk_attr.attr,
1265 &resume_offset_attr.attr,
1266 &resume_attr.attr,
1267 &image_size_attr.attr,
1268 &reserved_size_attr.attr,
1269 NULL,
1270};
1271
1272
1273static const struct attribute_group attr_group = {
1274 .attrs = g,
1275};
1276
1277
1278static int __init pm_disk_init(void)
1279{
1280 return sysfs_create_group(power_kobj, &attr_group);
1281}
1282
1283core_initcall(pm_disk_init);
1284
1285
1286static int __init resume_setup(char *str)
1287{
1288 if (noresume)
1289 return 1;
1290
1291 strncpy(resume_file, str, 255);
1292 return 1;
1293}
1294
1295static int __init resume_offset_setup(char *str)
1296{
1297 unsigned long long offset;
1298
1299 if (noresume)
1300 return 1;
1301
1302 if (sscanf(str, "%llu", &offset) == 1)
1303 swsusp_resume_block = offset;
1304
1305 return 1;
1306}
1307
1308static int __init hibernate_setup(char *str)
1309{
1310 if (!strncmp(str, "noresume", 8)) {
1311 noresume = 1;
1312 } else if (!strncmp(str, "nocompress", 10)) {
1313 nocompress = 1;
1314 } else if (!strncmp(str, "no", 2)) {
1315 noresume = 1;
1316 nohibernate = 1;
1317 } else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)
1318 && !strncmp(str, "protect_image", 13)) {
1319 enable_restore_image_protection();
1320 }
1321 return 1;
1322}
1323
1324static int __init noresume_setup(char *str)
1325{
1326 noresume = 1;
1327 return 1;
1328}
1329
1330static int __init resumewait_setup(char *str)
1331{
1332 resume_wait = 1;
1333 return 1;
1334}
1335
1336static int __init resumedelay_setup(char *str)
1337{
1338 int rc = kstrtouint(str, 0, &resume_delay);
1339
1340 if (rc)
1341 pr_warn("resumedelay: bad option string '%s'\n", str);
1342 return 1;
1343}
1344
1345static int __init nohibernate_setup(char *str)
1346{
1347 noresume = 1;
1348 nohibernate = 1;
1349 return 1;
1350}
1351
1352__setup("noresume", noresume_setup);
1353__setup("resume_offset=", resume_offset_setup);
1354__setup("resume=", resume_setup);
1355__setup("hibernate=", hibernate_setup);
1356__setup("resumewait", resumewait_setup);
1357__setup("resumedelay=", resumedelay_setup);
1358__setup("nohibernate", nohibernate_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#include <linux/ktime.h>
32#include <trace/events/power.h>
33
34#include "power.h"
35
36
37static int nocompress;
38static int noresume;
39static int nohibernate;
40static int resume_wait;
41static unsigned int resume_delay;
42static char resume_file[256] = CONFIG_PM_STD_PARTITION;
43dev_t swsusp_resume_device;
44sector_t swsusp_resume_block;
45__visible int in_suspend __nosavedata;
46
47enum {
48 HIBERNATION_INVALID,
49 HIBERNATION_PLATFORM,
50 HIBERNATION_SHUTDOWN,
51 HIBERNATION_REBOOT,
52#ifdef CONFIG_SUSPEND
53 HIBERNATION_SUSPEND,
54#endif
55 /* keep last */
56 __HIBERNATION_AFTER_LAST
57};
58#define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
59#define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
60
61static int hibernation_mode = HIBERNATION_SHUTDOWN;
62
63bool freezer_test_done;
64
65static const struct platform_hibernation_ops *hibernation_ops;
66
67bool hibernation_available(void)
68{
69 return (nohibernate == 0);
70}
71
72/**
73 * hibernation_set_ops - Set the global hibernate operations.
74 * @ops: Hibernation operations to use in subsequent hibernation transitions.
75 */
76void hibernation_set_ops(const struct platform_hibernation_ops *ops)
77{
78 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
79 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
80 && ops->restore_cleanup && ops->leave)) {
81 WARN_ON(1);
82 return;
83 }
84 lock_system_sleep();
85 hibernation_ops = ops;
86 if (ops)
87 hibernation_mode = HIBERNATION_PLATFORM;
88 else if (hibernation_mode == HIBERNATION_PLATFORM)
89 hibernation_mode = HIBERNATION_SHUTDOWN;
90
91 unlock_system_sleep();
92}
93EXPORT_SYMBOL_GPL(hibernation_set_ops);
94
95static bool entering_platform_hibernation;
96
97bool system_entering_hibernation(void)
98{
99 return entering_platform_hibernation;
100}
101EXPORT_SYMBOL(system_entering_hibernation);
102
103#ifdef CONFIG_PM_DEBUG
104static void hibernation_debug_sleep(void)
105{
106 printk(KERN_INFO "hibernation debug: Waiting for 5 seconds.\n");
107 mdelay(5000);
108}
109
110static int hibernation_test(int level)
111{
112 if (pm_test_level == level) {
113 hibernation_debug_sleep();
114 return 1;
115 }
116 return 0;
117}
118#else /* !CONFIG_PM_DEBUG */
119static int hibernation_test(int level) { return 0; }
120#endif /* !CONFIG_PM_DEBUG */
121
122/**
123 * platform_begin - Call platform to start hibernation.
124 * @platform_mode: Whether or not to use the platform driver.
125 */
126static int platform_begin(int platform_mode)
127{
128 return (platform_mode && hibernation_ops) ?
129 hibernation_ops->begin() : 0;
130}
131
132/**
133 * platform_end - Call platform to finish transition to the working state.
134 * @platform_mode: Whether or not to use the platform driver.
135 */
136static void platform_end(int platform_mode)
137{
138 if (platform_mode && hibernation_ops)
139 hibernation_ops->end();
140}
141
142/**
143 * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
144 * @platform_mode: Whether or not to use the platform driver.
145 *
146 * Use the platform driver to prepare the system for creating a hibernate image,
147 * if so configured, and return an error code if that fails.
148 */
149
150static int platform_pre_snapshot(int platform_mode)
151{
152 return (platform_mode && hibernation_ops) ?
153 hibernation_ops->pre_snapshot() : 0;
154}
155
156/**
157 * platform_leave - Call platform to prepare a transition to the working state.
158 * @platform_mode: Whether or not to use the platform driver.
159 *
160 * Use the platform driver prepare to prepare the machine for switching to the
161 * normal mode of operation.
162 *
163 * This routine is called on one CPU with interrupts disabled.
164 */
165static void platform_leave(int platform_mode)
166{
167 if (platform_mode && hibernation_ops)
168 hibernation_ops->leave();
169}
170
171/**
172 * platform_finish - Call platform to switch the system to the working state.
173 * @platform_mode: Whether or not to use the platform driver.
174 *
175 * Use the platform driver to switch the machine to the normal mode of
176 * operation.
177 *
178 * This routine must be called after platform_prepare().
179 */
180static void platform_finish(int platform_mode)
181{
182 if (platform_mode && hibernation_ops)
183 hibernation_ops->finish();
184}
185
186/**
187 * platform_pre_restore - Prepare for hibernate image restoration.
188 * @platform_mode: Whether or not to use the platform driver.
189 *
190 * Use the platform driver to prepare the system for resume from a hibernation
191 * image.
192 *
193 * If the restore fails after this function has been called,
194 * platform_restore_cleanup() must be called.
195 */
196static int platform_pre_restore(int platform_mode)
197{
198 return (platform_mode && hibernation_ops) ?
199 hibernation_ops->pre_restore() : 0;
200}
201
202/**
203 * platform_restore_cleanup - Switch to the working state after failing restore.
204 * @platform_mode: Whether or not to use the platform driver.
205 *
206 * Use the platform driver to switch the system to the normal mode of operation
207 * after a failing restore.
208 *
209 * If platform_pre_restore() has been called before the failing restore, this
210 * function must be called too, regardless of the result of
211 * platform_pre_restore().
212 */
213static void platform_restore_cleanup(int platform_mode)
214{
215 if (platform_mode && hibernation_ops)
216 hibernation_ops->restore_cleanup();
217}
218
219/**
220 * platform_recover - Recover from a failure to suspend devices.
221 * @platform_mode: Whether or not to use the platform driver.
222 */
223static void platform_recover(int platform_mode)
224{
225 if (platform_mode && hibernation_ops && hibernation_ops->recover)
226 hibernation_ops->recover();
227}
228
229/**
230 * swsusp_show_speed - Print time elapsed between two events during hibernation.
231 * @start: Starting event.
232 * @stop: Final event.
233 * @nr_pages: Number of memory pages processed between @start and @stop.
234 * @msg: Additional diagnostic message to print.
235 */
236void swsusp_show_speed(ktime_t start, ktime_t stop,
237 unsigned nr_pages, char *msg)
238{
239 ktime_t diff;
240 u64 elapsed_centisecs64;
241 unsigned int centisecs;
242 unsigned int k;
243 unsigned int kps;
244
245 diff = ktime_sub(stop, start);
246 elapsed_centisecs64 = ktime_divns(diff, 10*NSEC_PER_MSEC);
247 centisecs = elapsed_centisecs64;
248 if (centisecs == 0)
249 centisecs = 1; /* avoid div-by-zero */
250 k = nr_pages * (PAGE_SIZE / 1024);
251 kps = (k * 100) / centisecs;
252 printk(KERN_INFO "PM: %s %u kbytes in %u.%02u seconds (%u.%02u MB/s)\n",
253 msg, k,
254 centisecs / 100, centisecs % 100,
255 kps / 1000, (kps % 1000) / 10);
256}
257
258/**
259 * create_image - Create a hibernation image.
260 * @platform_mode: Whether or not to use the platform driver.
261 *
262 * Execute device drivers' "late" and "noirq" freeze callbacks, create a
263 * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
264 *
265 * Control reappears in this routine after the subsequent restore.
266 */
267static int create_image(int platform_mode)
268{
269 int error;
270
271 error = dpm_suspend_end(PMSG_FREEZE);
272 if (error) {
273 printk(KERN_ERR "PM: Some devices failed to power down, "
274 "aborting hibernation\n");
275 return error;
276 }
277
278 error = platform_pre_snapshot(platform_mode);
279 if (error || hibernation_test(TEST_PLATFORM))
280 goto Platform_finish;
281
282 error = disable_nonboot_cpus();
283 if (error || hibernation_test(TEST_CPUS))
284 goto Enable_cpus;
285
286 local_irq_disable();
287
288 error = syscore_suspend();
289 if (error) {
290 printk(KERN_ERR "PM: Some system devices failed to power down, "
291 "aborting hibernation\n");
292 goto Enable_irqs;
293 }
294
295 if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
296 goto Power_up;
297
298 in_suspend = 1;
299 save_processor_state();
300 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true);
301 error = swsusp_arch_suspend();
302 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false);
303 if (error)
304 printk(KERN_ERR "PM: Error %d creating hibernation image\n",
305 error);
306 /* Restore control flow magically appears here */
307 restore_processor_state();
308 if (!in_suspend)
309 events_check_enabled = false;
310
311 platform_leave(platform_mode);
312
313 Power_up:
314 syscore_resume();
315
316 Enable_irqs:
317 local_irq_enable();
318
319 Enable_cpus:
320 enable_nonboot_cpus();
321
322 Platform_finish:
323 platform_finish(platform_mode);
324
325 dpm_resume_start(in_suspend ?
326 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
327
328 return error;
329}
330
331/**
332 * hibernation_snapshot - Quiesce devices and create a hibernation image.
333 * @platform_mode: If set, use platform driver to prepare for the transition.
334 *
335 * This routine must be called with pm_mutex held.
336 */
337int hibernation_snapshot(int platform_mode)
338{
339 pm_message_t msg;
340 int error;
341
342 pm_suspend_clear_flags();
343 error = platform_begin(platform_mode);
344 if (error)
345 goto Close;
346
347 /* Preallocate image memory before shutting down devices. */
348 error = hibernate_preallocate_memory();
349 if (error)
350 goto Close;
351
352 error = freeze_kernel_threads();
353 if (error)
354 goto Cleanup;
355
356 if (hibernation_test(TEST_FREEZER)) {
357
358 /*
359 * Indicate to the caller that we are returning due to a
360 * successful freezer test.
361 */
362 freezer_test_done = true;
363 goto Thaw;
364 }
365
366 error = dpm_prepare(PMSG_FREEZE);
367 if (error) {
368 dpm_complete(PMSG_RECOVER);
369 goto Thaw;
370 }
371
372 suspend_console();
373 pm_restrict_gfp_mask();
374
375 error = dpm_suspend(PMSG_FREEZE);
376
377 if (error || hibernation_test(TEST_DEVICES))
378 platform_recover(platform_mode);
379 else
380 error = create_image(platform_mode);
381
382 /*
383 * In the case that we call create_image() above, the control
384 * returns here (1) after the image has been created or the
385 * image creation has failed and (2) after a successful restore.
386 */
387
388 /* We may need to release the preallocated image pages here. */
389 if (error || !in_suspend)
390 swsusp_free();
391
392 msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
393 dpm_resume(msg);
394
395 if (error || !in_suspend)
396 pm_restore_gfp_mask();
397
398 resume_console();
399 dpm_complete(msg);
400
401 Close:
402 platform_end(platform_mode);
403 return error;
404
405 Thaw:
406 thaw_kernel_threads();
407 Cleanup:
408 swsusp_free();
409 goto Close;
410}
411
412/**
413 * resume_target_kernel - Restore system state from a hibernation image.
414 * @platform_mode: Whether or not to use the platform driver.
415 *
416 * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
417 * contents of highmem that have not been restored yet from the image and run
418 * the low-level code that will restore the remaining contents of memory and
419 * switch to the just restored target kernel.
420 */
421static int resume_target_kernel(bool platform_mode)
422{
423 int error;
424
425 error = dpm_suspend_end(PMSG_QUIESCE);
426 if (error) {
427 printk(KERN_ERR "PM: Some devices failed to power down, "
428 "aborting resume\n");
429 return error;
430 }
431
432 error = platform_pre_restore(platform_mode);
433 if (error)
434 goto Cleanup;
435
436 error = disable_nonboot_cpus();
437 if (error)
438 goto Enable_cpus;
439
440 local_irq_disable();
441
442 error = syscore_suspend();
443 if (error)
444 goto Enable_irqs;
445
446 save_processor_state();
447 error = restore_highmem();
448 if (!error) {
449 error = swsusp_arch_resume();
450 /*
451 * The code below is only ever reached in case of a failure.
452 * Otherwise, execution continues at the place where
453 * swsusp_arch_suspend() was called.
454 */
455 BUG_ON(!error);
456 /*
457 * This call to restore_highmem() reverts the changes made by
458 * the previous one.
459 */
460 restore_highmem();
461 }
462 /*
463 * The only reason why swsusp_arch_resume() can fail is memory being
464 * very tight, so we have to free it as soon as we can to avoid
465 * subsequent failures.
466 */
467 swsusp_free();
468 restore_processor_state();
469 touch_softlockup_watchdog();
470
471 syscore_resume();
472
473 Enable_irqs:
474 local_irq_enable();
475
476 Enable_cpus:
477 enable_nonboot_cpus();
478
479 Cleanup:
480 platform_restore_cleanup(platform_mode);
481
482 dpm_resume_start(PMSG_RECOVER);
483
484 return error;
485}
486
487/**
488 * hibernation_restore - Quiesce devices and restore from a hibernation image.
489 * @platform_mode: If set, use platform driver to prepare for the transition.
490 *
491 * This routine must be called with pm_mutex held. If it is successful, control
492 * reappears in the restored target kernel in hibernation_snapshot().
493 */
494int hibernation_restore(int platform_mode)
495{
496 int error;
497
498 pm_prepare_console();
499 suspend_console();
500 pm_restrict_gfp_mask();
501 error = dpm_suspend_start(PMSG_QUIESCE);
502 if (!error) {
503 error = resume_target_kernel(platform_mode);
504 /*
505 * The above should either succeed and jump to the new kernel,
506 * or return with an error. Otherwise things are just
507 * undefined, so let's be paranoid.
508 */
509 BUG_ON(!error);
510 }
511 dpm_resume_end(PMSG_RECOVER);
512 pm_restore_gfp_mask();
513 resume_console();
514 pm_restore_console();
515 return error;
516}
517
518/**
519 * hibernation_platform_enter - Power off the system using the platform driver.
520 */
521int hibernation_platform_enter(void)
522{
523 int error;
524
525 if (!hibernation_ops)
526 return -ENOSYS;
527
528 /*
529 * We have cancelled the power transition by running
530 * hibernation_ops->finish() before saving the image, so we should let
531 * the firmware know that we're going to enter the sleep state after all
532 */
533 error = hibernation_ops->begin();
534 if (error)
535 goto Close;
536
537 entering_platform_hibernation = true;
538 suspend_console();
539 error = dpm_suspend_start(PMSG_HIBERNATE);
540 if (error) {
541 if (hibernation_ops->recover)
542 hibernation_ops->recover();
543 goto Resume_devices;
544 }
545
546 error = dpm_suspend_end(PMSG_HIBERNATE);
547 if (error)
548 goto Resume_devices;
549
550 error = hibernation_ops->prepare();
551 if (error)
552 goto Platform_finish;
553
554 error = disable_nonboot_cpus();
555 if (error)
556 goto Enable_cpus;
557
558 local_irq_disable();
559 syscore_suspend();
560 if (pm_wakeup_pending()) {
561 error = -EAGAIN;
562 goto Power_up;
563 }
564
565 hibernation_ops->enter();
566 /* We should never get here */
567 while (1);
568
569 Power_up:
570 syscore_resume();
571 local_irq_enable();
572
573 Enable_cpus:
574 enable_nonboot_cpus();
575
576 Platform_finish:
577 hibernation_ops->finish();
578
579 dpm_resume_start(PMSG_RESTORE);
580
581 Resume_devices:
582 entering_platform_hibernation = false;
583 dpm_resume_end(PMSG_RESTORE);
584 resume_console();
585
586 Close:
587 hibernation_ops->end();
588
589 return error;
590}
591
592/**
593 * power_down - Shut the machine down for hibernation.
594 *
595 * Use the platform driver, if configured, to put the system into the sleep
596 * state corresponding to hibernation, or try to power it off or reboot,
597 * depending on the value of hibernation_mode.
598 */
599static void power_down(void)
600{
601#ifdef CONFIG_SUSPEND
602 int error;
603#endif
604
605 switch (hibernation_mode) {
606 case HIBERNATION_REBOOT:
607 kernel_restart(NULL);
608 break;
609 case HIBERNATION_PLATFORM:
610 hibernation_platform_enter();
611 case HIBERNATION_SHUTDOWN:
612 if (pm_power_off)
613 kernel_power_off();
614 break;
615#ifdef CONFIG_SUSPEND
616 case HIBERNATION_SUSPEND:
617 error = suspend_devices_and_enter(PM_SUSPEND_MEM);
618 if (error) {
619 if (hibernation_ops)
620 hibernation_mode = HIBERNATION_PLATFORM;
621 else
622 hibernation_mode = HIBERNATION_SHUTDOWN;
623 power_down();
624 }
625 /*
626 * Restore swap signature.
627 */
628 error = swsusp_unmark();
629 if (error)
630 printk(KERN_ERR "PM: Swap will be unusable! "
631 "Try swapon -a.\n");
632 return;
633#endif
634 }
635 kernel_halt();
636 /*
637 * Valid image is on the disk, if we continue we risk serious data
638 * corruption after resume.
639 */
640 printk(KERN_CRIT "PM: Please power down manually\n");
641 while (1)
642 cpu_relax();
643}
644
645/**
646 * hibernate - Carry out system hibernation, including saving the image.
647 */
648int hibernate(void)
649{
650 int error;
651
652 if (!hibernation_available()) {
653 pr_debug("PM: Hibernation not available.\n");
654 return -EPERM;
655 }
656
657 lock_system_sleep();
658 /* The snapshot device should not be opened while we're running */
659 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
660 error = -EBUSY;
661 goto Unlock;
662 }
663
664 pm_prepare_console();
665 error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
666 if (error)
667 goto Exit;
668
669 printk(KERN_INFO "PM: Syncing filesystems ... ");
670 sys_sync();
671 printk("done.\n");
672
673 error = freeze_processes();
674 if (error)
675 goto Exit;
676
677 lock_device_hotplug();
678 /* Allocate memory management structures */
679 error = create_basic_memory_bitmaps();
680 if (error)
681 goto Thaw;
682
683 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
684 if (error || freezer_test_done)
685 goto Free_bitmaps;
686
687 if (in_suspend) {
688 unsigned int flags = 0;
689
690 if (hibernation_mode == HIBERNATION_PLATFORM)
691 flags |= SF_PLATFORM_MODE;
692 if (nocompress)
693 flags |= SF_NOCOMPRESS_MODE;
694 else
695 flags |= SF_CRC32_MODE;
696
697 pr_debug("PM: writing image.\n");
698 error = swsusp_write(flags);
699 swsusp_free();
700 if (!error)
701 power_down();
702 in_suspend = 0;
703 pm_restore_gfp_mask();
704 } else {
705 pr_debug("PM: Image restored successfully.\n");
706 }
707
708 Free_bitmaps:
709 free_basic_memory_bitmaps();
710 Thaw:
711 unlock_device_hotplug();
712 thaw_processes();
713
714 /* Don't bother checking whether freezer_test_done is true */
715 freezer_test_done = false;
716 Exit:
717 pm_notifier_call_chain(PM_POST_HIBERNATION);
718 pm_restore_console();
719 atomic_inc(&snapshot_device_available);
720 Unlock:
721 unlock_system_sleep();
722 return error;
723}
724
725
726/**
727 * software_resume - Resume from a saved hibernation image.
728 *
729 * This routine is called as a late initcall, when all devices have been
730 * discovered and initialized already.
731 *
732 * The image reading code is called to see if there is a hibernation image
733 * available for reading. If that is the case, devices are quiesced and the
734 * contents of memory is restored from the saved image.
735 *
736 * If this is successful, control reappears in the restored target kernel in
737 * hibernation_snapshot() which returns to hibernate(). Otherwise, the routine
738 * attempts to recover gracefully and make the kernel return to the normal mode
739 * of operation.
740 */
741static int software_resume(void)
742{
743 int error;
744 unsigned int flags;
745
746 /*
747 * If the user said "noresume".. bail out early.
748 */
749 if (noresume || !hibernation_available())
750 return 0;
751
752 /*
753 * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
754 * is configured into the kernel. Since the regular hibernate
755 * trigger path is via sysfs which takes a buffer mutex before
756 * calling hibernate functions (which take pm_mutex) this can
757 * cause lockdep to complain about a possible ABBA deadlock
758 * which cannot happen since we're in the boot code here and
759 * sysfs can't be invoked yet. Therefore, we use a subclass
760 * here to avoid lockdep complaining.
761 */
762 mutex_lock_nested(&pm_mutex, SINGLE_DEPTH_NESTING);
763
764 if (swsusp_resume_device)
765 goto Check_image;
766
767 if (!strlen(resume_file)) {
768 error = -ENOENT;
769 goto Unlock;
770 }
771
772 pr_debug("PM: Checking hibernation image partition %s\n", resume_file);
773
774 if (resume_delay) {
775 printk(KERN_INFO "Waiting %dsec before reading resume device...\n",
776 resume_delay);
777 ssleep(resume_delay);
778 }
779
780 /* Check if the device is there */
781 swsusp_resume_device = name_to_dev_t(resume_file);
782
783 /*
784 * name_to_dev_t is ineffective to verify parition if resume_file is in
785 * integer format. (e.g. major:minor)
786 */
787 if (isdigit(resume_file[0]) && resume_wait) {
788 int partno;
789 while (!get_gendisk(swsusp_resume_device, &partno))
790 msleep(10);
791 }
792
793 if (!swsusp_resume_device) {
794 /*
795 * Some device discovery might still be in progress; we need
796 * to wait for this to finish.
797 */
798 wait_for_device_probe();
799
800 if (resume_wait) {
801 while ((swsusp_resume_device = name_to_dev_t(resume_file)) == 0)
802 msleep(10);
803 async_synchronize_full();
804 }
805
806 swsusp_resume_device = name_to_dev_t(resume_file);
807 if (!swsusp_resume_device) {
808 error = -ENODEV;
809 goto Unlock;
810 }
811 }
812
813 Check_image:
814 pr_debug("PM: Hibernation image partition %d:%d present\n",
815 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
816
817 pr_debug("PM: Looking for hibernation image.\n");
818 error = swsusp_check();
819 if (error)
820 goto Unlock;
821
822 /* The snapshot device should not be opened while we're running */
823 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
824 error = -EBUSY;
825 swsusp_close(FMODE_READ);
826 goto Unlock;
827 }
828
829 pm_prepare_console();
830 error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
831 if (error)
832 goto Close_Finish;
833
834 pr_debug("PM: Preparing processes for restore.\n");
835 error = freeze_processes();
836 if (error)
837 goto Close_Finish;
838
839 pr_debug("PM: Loading hibernation image.\n");
840
841 lock_device_hotplug();
842 error = create_basic_memory_bitmaps();
843 if (error)
844 goto Thaw;
845
846 error = swsusp_read(&flags);
847 swsusp_close(FMODE_READ);
848 if (!error)
849 hibernation_restore(flags & SF_PLATFORM_MODE);
850
851 printk(KERN_ERR "PM: Failed to load hibernation image, recovering.\n");
852 swsusp_free();
853 free_basic_memory_bitmaps();
854 Thaw:
855 unlock_device_hotplug();
856 thaw_processes();
857 Finish:
858 pm_notifier_call_chain(PM_POST_RESTORE);
859 pm_restore_console();
860 atomic_inc(&snapshot_device_available);
861 /* For success case, the suspend path will release the lock */
862 Unlock:
863 mutex_unlock(&pm_mutex);
864 pr_debug("PM: Hibernation image not present or could not be loaded.\n");
865 return error;
866 Close_Finish:
867 swsusp_close(FMODE_READ);
868 goto Finish;
869}
870
871late_initcall_sync(software_resume);
872
873
874static const char * const hibernation_modes[] = {
875 [HIBERNATION_PLATFORM] = "platform",
876 [HIBERNATION_SHUTDOWN] = "shutdown",
877 [HIBERNATION_REBOOT] = "reboot",
878#ifdef CONFIG_SUSPEND
879 [HIBERNATION_SUSPEND] = "suspend",
880#endif
881};
882
883/*
884 * /sys/power/disk - Control hibernation mode.
885 *
886 * Hibernation can be handled in several ways. There are a few different ways
887 * to put the system into the sleep state: using the platform driver (e.g. ACPI
888 * or other hibernation_ops), powering it off or rebooting it (for testing
889 * mostly).
890 *
891 * The sysfs file /sys/power/disk provides an interface for selecting the
892 * hibernation mode to use. Reading from this file causes the available modes
893 * to be printed. There are 3 modes that can be supported:
894 *
895 * 'platform'
896 * 'shutdown'
897 * 'reboot'
898 *
899 * If a platform hibernation driver is in use, 'platform' will be supported
900 * and will be used by default. Otherwise, 'shutdown' will be used by default.
901 * The selected option (i.e. the one corresponding to the current value of
902 * hibernation_mode) is enclosed by a square bracket.
903 *
904 * To select a given hibernation mode it is necessary to write the mode's
905 * string representation (as returned by reading from /sys/power/disk) back
906 * into /sys/power/disk.
907 */
908
909static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
910 char *buf)
911{
912 int i;
913 char *start = buf;
914
915 if (!hibernation_available())
916 return sprintf(buf, "[disabled]\n");
917
918 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
919 if (!hibernation_modes[i])
920 continue;
921 switch (i) {
922 case HIBERNATION_SHUTDOWN:
923 case HIBERNATION_REBOOT:
924#ifdef CONFIG_SUSPEND
925 case HIBERNATION_SUSPEND:
926#endif
927 break;
928 case HIBERNATION_PLATFORM:
929 if (hibernation_ops)
930 break;
931 /* not a valid mode, continue with loop */
932 continue;
933 }
934 if (i == hibernation_mode)
935 buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
936 else
937 buf += sprintf(buf, "%s ", hibernation_modes[i]);
938 }
939 buf += sprintf(buf, "\n");
940 return buf-start;
941}
942
943static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
944 const char *buf, size_t n)
945{
946 int error = 0;
947 int i;
948 int len;
949 char *p;
950 int mode = HIBERNATION_INVALID;
951
952 if (!hibernation_available())
953 return -EPERM;
954
955 p = memchr(buf, '\n', n);
956 len = p ? p - buf : n;
957
958 lock_system_sleep();
959 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
960 if (len == strlen(hibernation_modes[i])
961 && !strncmp(buf, hibernation_modes[i], len)) {
962 mode = i;
963 break;
964 }
965 }
966 if (mode != HIBERNATION_INVALID) {
967 switch (mode) {
968 case HIBERNATION_SHUTDOWN:
969 case HIBERNATION_REBOOT:
970#ifdef CONFIG_SUSPEND
971 case HIBERNATION_SUSPEND:
972#endif
973 hibernation_mode = mode;
974 break;
975 case HIBERNATION_PLATFORM:
976 if (hibernation_ops)
977 hibernation_mode = mode;
978 else
979 error = -EINVAL;
980 }
981 } else
982 error = -EINVAL;
983
984 if (!error)
985 pr_debug("PM: Hibernation mode set to '%s'\n",
986 hibernation_modes[mode]);
987 unlock_system_sleep();
988 return error ? error : n;
989}
990
991power_attr(disk);
992
993static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
994 char *buf)
995{
996 return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
997 MINOR(swsusp_resume_device));
998}
999
1000static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
1001 const char *buf, size_t n)
1002{
1003 dev_t res;
1004 int len = n;
1005 char *name;
1006
1007 if (len && buf[len-1] == '\n')
1008 len--;
1009 name = kstrndup(buf, len, GFP_KERNEL);
1010 if (!name)
1011 return -ENOMEM;
1012
1013 res = name_to_dev_t(name);
1014 kfree(name);
1015 if (!res)
1016 return -EINVAL;
1017
1018 lock_system_sleep();
1019 swsusp_resume_device = res;
1020 unlock_system_sleep();
1021 printk(KERN_INFO "PM: Starting manual resume from disk\n");
1022 noresume = 0;
1023 software_resume();
1024 return n;
1025}
1026
1027power_attr(resume);
1028
1029static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
1030 char *buf)
1031{
1032 return sprintf(buf, "%lu\n", image_size);
1033}
1034
1035static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
1036 const char *buf, size_t n)
1037{
1038 unsigned long size;
1039
1040 if (sscanf(buf, "%lu", &size) == 1) {
1041 image_size = size;
1042 return n;
1043 }
1044
1045 return -EINVAL;
1046}
1047
1048power_attr(image_size);
1049
1050static ssize_t reserved_size_show(struct kobject *kobj,
1051 struct kobj_attribute *attr, char *buf)
1052{
1053 return sprintf(buf, "%lu\n", reserved_size);
1054}
1055
1056static ssize_t reserved_size_store(struct kobject *kobj,
1057 struct kobj_attribute *attr,
1058 const char *buf, size_t n)
1059{
1060 unsigned long size;
1061
1062 if (sscanf(buf, "%lu", &size) == 1) {
1063 reserved_size = size;
1064 return n;
1065 }
1066
1067 return -EINVAL;
1068}
1069
1070power_attr(reserved_size);
1071
1072static struct attribute * g[] = {
1073 &disk_attr.attr,
1074 &resume_attr.attr,
1075 &image_size_attr.attr,
1076 &reserved_size_attr.attr,
1077 NULL,
1078};
1079
1080
1081static struct attribute_group attr_group = {
1082 .attrs = g,
1083};
1084
1085
1086static int __init pm_disk_init(void)
1087{
1088 return sysfs_create_group(power_kobj, &attr_group);
1089}
1090
1091core_initcall(pm_disk_init);
1092
1093
1094static int __init resume_setup(char *str)
1095{
1096 if (noresume)
1097 return 1;
1098
1099 strncpy( resume_file, str, 255 );
1100 return 1;
1101}
1102
1103static int __init resume_offset_setup(char *str)
1104{
1105 unsigned long long offset;
1106
1107 if (noresume)
1108 return 1;
1109
1110 if (sscanf(str, "%llu", &offset) == 1)
1111 swsusp_resume_block = offset;
1112
1113 return 1;
1114}
1115
1116static int __init hibernate_setup(char *str)
1117{
1118 if (!strncmp(str, "noresume", 8))
1119 noresume = 1;
1120 else if (!strncmp(str, "nocompress", 10))
1121 nocompress = 1;
1122 else if (!strncmp(str, "no", 2)) {
1123 noresume = 1;
1124 nohibernate = 1;
1125 }
1126 return 1;
1127}
1128
1129static int __init noresume_setup(char *str)
1130{
1131 noresume = 1;
1132 return 1;
1133}
1134
1135static int __init resumewait_setup(char *str)
1136{
1137 resume_wait = 1;
1138 return 1;
1139}
1140
1141static int __init resumedelay_setup(char *str)
1142{
1143 int rc = kstrtouint(str, 0, &resume_delay);
1144
1145 if (rc)
1146 return rc;
1147 return 1;
1148}
1149
1150static int __init nohibernate_setup(char *str)
1151{
1152 noresume = 1;
1153 nohibernate = 1;
1154 return 1;
1155}
1156
1157static int __init kaslr_nohibernate_setup(char *str)
1158{
1159 return nohibernate_setup(str);
1160}
1161
1162static int __init page_poison_nohibernate_setup(char *str)
1163{
1164#ifdef CONFIG_PAGE_POISONING_ZERO
1165 /*
1166 * The zeroing option for page poison skips the checks on alloc.
1167 * since hibernation doesn't save free pages there's no way to
1168 * guarantee the pages will still be zeroed.
1169 */
1170 if (!strcmp(str, "on")) {
1171 pr_info("Disabling hibernation due to page poisoning\n");
1172 return nohibernate_setup(str);
1173 }
1174#endif
1175 return 1;
1176}
1177
1178__setup("noresume", noresume_setup);
1179__setup("resume_offset=", resume_offset_setup);
1180__setup("resume=", resume_setup);
1181__setup("hibernate=", hibernate_setup);
1182__setup("resumewait", resumewait_setup);
1183__setup("resumedelay=", resumedelay_setup);
1184__setup("nohibernate", nohibernate_setup);
1185__setup("kaslr", kaslr_nohibernate_setup);
1186__setup("page_poison=", page_poison_nohibernate_setup);