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