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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/genhd.h>
32#include <linux/ktime.h>
33#include <linux/security.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 && !security_locked_down(LOCKDOWN_HIBERNATION);
85}
86
87/**
88 * hibernation_set_ops - Set the global hibernate operations.
89 * @ops: Hibernation operations to use in subsequent hibernation transitions.
90 */
91void hibernation_set_ops(const struct platform_hibernation_ops *ops)
92{
93 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
94 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
95 && ops->restore_cleanup && ops->leave)) {
96 WARN_ON(1);
97 return;
98 }
99 lock_system_sleep();
100 hibernation_ops = ops;
101 if (ops)
102 hibernation_mode = HIBERNATION_PLATFORM;
103 else if (hibernation_mode == HIBERNATION_PLATFORM)
104 hibernation_mode = HIBERNATION_SHUTDOWN;
105
106 unlock_system_sleep();
107}
108EXPORT_SYMBOL_GPL(hibernation_set_ops);
109
110static bool entering_platform_hibernation;
111
112bool system_entering_hibernation(void)
113{
114 return entering_platform_hibernation;
115}
116EXPORT_SYMBOL(system_entering_hibernation);
117
118#ifdef CONFIG_PM_DEBUG
119static void hibernation_debug_sleep(void)
120{
121 pr_info("debug: Waiting for 5 seconds.\n");
122 mdelay(5000);
123}
124
125static int hibernation_test(int level)
126{
127 if (pm_test_level == level) {
128 hibernation_debug_sleep();
129 return 1;
130 }
131 return 0;
132}
133#else /* !CONFIG_PM_DEBUG */
134static int hibernation_test(int level) { return 0; }
135#endif /* !CONFIG_PM_DEBUG */
136
137/**
138 * platform_begin - Call platform to start hibernation.
139 * @platform_mode: Whether or not to use the platform driver.
140 */
141static int platform_begin(int platform_mode)
142{
143 return (platform_mode && hibernation_ops) ?
144 hibernation_ops->begin(PMSG_FREEZE) : 0;
145}
146
147/**
148 * platform_end - Call platform to finish transition to the working state.
149 * @platform_mode: Whether or not to use the platform driver.
150 */
151static void platform_end(int platform_mode)
152{
153 if (platform_mode && hibernation_ops)
154 hibernation_ops->end();
155}
156
157/**
158 * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
159 * @platform_mode: Whether or not to use the platform driver.
160 *
161 * Use the platform driver to prepare the system for creating a hibernate image,
162 * if so configured, and return an error code if that fails.
163 */
164
165static int platform_pre_snapshot(int platform_mode)
166{
167 return (platform_mode && hibernation_ops) ?
168 hibernation_ops->pre_snapshot() : 0;
169}
170
171/**
172 * platform_leave - Call platform to prepare a transition to the working state.
173 * @platform_mode: Whether or not to use the platform driver.
174 *
175 * Use the platform driver prepare to prepare the machine for switching to the
176 * normal mode of operation.
177 *
178 * This routine is called on one CPU with interrupts disabled.
179 */
180static void platform_leave(int platform_mode)
181{
182 if (platform_mode && hibernation_ops)
183 hibernation_ops->leave();
184}
185
186/**
187 * platform_finish - Call platform to switch the system to the working state.
188 * @platform_mode: Whether or not to use the platform driver.
189 *
190 * Use the platform driver to switch the machine to the normal mode of
191 * operation.
192 *
193 * This routine must be called after platform_prepare().
194 */
195static void platform_finish(int platform_mode)
196{
197 if (platform_mode && hibernation_ops)
198 hibernation_ops->finish();
199}
200
201/**
202 * platform_pre_restore - Prepare for hibernate image restoration.
203 * @platform_mode: Whether or not to use the platform driver.
204 *
205 * Use the platform driver to prepare the system for resume from a hibernation
206 * image.
207 *
208 * If the restore fails after this function has been called,
209 * platform_restore_cleanup() must be called.
210 */
211static int platform_pre_restore(int platform_mode)
212{
213 return (platform_mode && hibernation_ops) ?
214 hibernation_ops->pre_restore() : 0;
215}
216
217/**
218 * platform_restore_cleanup - Switch to the working state after failing restore.
219 * @platform_mode: Whether or not to use the platform driver.
220 *
221 * Use the platform driver to switch the system to the normal mode of operation
222 * after a failing restore.
223 *
224 * If platform_pre_restore() has been called before the failing restore, this
225 * function must be called too, regardless of the result of
226 * platform_pre_restore().
227 */
228static void platform_restore_cleanup(int platform_mode)
229{
230 if (platform_mode && hibernation_ops)
231 hibernation_ops->restore_cleanup();
232}
233
234/**
235 * platform_recover - Recover from a failure to suspend devices.
236 * @platform_mode: Whether or not to use the platform driver.
237 */
238static void platform_recover(int platform_mode)
239{
240 if (platform_mode && hibernation_ops && hibernation_ops->recover)
241 hibernation_ops->recover();
242}
243
244/**
245 * swsusp_show_speed - Print time elapsed between two events during hibernation.
246 * @start: Starting event.
247 * @stop: Final event.
248 * @nr_pages: Number of memory pages processed between @start and @stop.
249 * @msg: Additional diagnostic message to print.
250 */
251void swsusp_show_speed(ktime_t start, ktime_t stop,
252 unsigned nr_pages, char *msg)
253{
254 ktime_t diff;
255 u64 elapsed_centisecs64;
256 unsigned int centisecs;
257 unsigned int k;
258 unsigned int kps;
259
260 diff = ktime_sub(stop, start);
261 elapsed_centisecs64 = ktime_divns(diff, 10*NSEC_PER_MSEC);
262 centisecs = elapsed_centisecs64;
263 if (centisecs == 0)
264 centisecs = 1; /* avoid div-by-zero */
265 k = nr_pages * (PAGE_SIZE / 1024);
266 kps = (k * 100) / centisecs;
267 pr_info("%s %u kbytes in %u.%02u seconds (%u.%02u MB/s)\n",
268 msg, k, centisecs / 100, centisecs % 100, kps / 1000,
269 (kps % 1000) / 10);
270}
271
272__weak int arch_resume_nosmt(void)
273{
274 return 0;
275}
276
277/**
278 * create_image - Create a hibernation image.
279 * @platform_mode: Whether or not to use the platform driver.
280 *
281 * Execute device drivers' "late" and "noirq" freeze callbacks, create a
282 * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
283 *
284 * Control reappears in this routine after the subsequent restore.
285 */
286static int create_image(int platform_mode)
287{
288 int error;
289
290 error = dpm_suspend_end(PMSG_FREEZE);
291 if (error) {
292 pr_err("Some devices failed to power down, aborting\n");
293 return error;
294 }
295
296 error = platform_pre_snapshot(platform_mode);
297 if (error || hibernation_test(TEST_PLATFORM))
298 goto Platform_finish;
299
300 error = suspend_disable_secondary_cpus();
301 if (error || hibernation_test(TEST_CPUS))
302 goto Enable_cpus;
303
304 local_irq_disable();
305
306 system_state = SYSTEM_SUSPEND;
307
308 error = syscore_suspend();
309 if (error) {
310 pr_err("Some system devices failed to power down, aborting\n");
311 goto Enable_irqs;
312 }
313
314 if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
315 goto Power_up;
316
317 in_suspend = 1;
318 save_processor_state();
319 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true);
320 error = swsusp_arch_suspend();
321 /* Restore control flow magically appears here */
322 restore_processor_state();
323 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false);
324 if (error)
325 pr_err("Error %d creating image\n", error);
326
327 if (!in_suspend) {
328 events_check_enabled = false;
329 clear_free_pages();
330 }
331
332 platform_leave(platform_mode);
333
334 Power_up:
335 syscore_resume();
336
337 Enable_irqs:
338 system_state = SYSTEM_RUNNING;
339 local_irq_enable();
340
341 Enable_cpus:
342 suspend_enable_secondary_cpus();
343
344 /* Allow architectures to do nosmt-specific post-resume dances */
345 if (!in_suspend)
346 error = arch_resume_nosmt();
347
348 Platform_finish:
349 platform_finish(platform_mode);
350
351 dpm_resume_start(in_suspend ?
352 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
353
354 return error;
355}
356
357/**
358 * hibernation_snapshot - Quiesce devices and create a hibernation image.
359 * @platform_mode: If set, use platform driver to prepare for the transition.
360 *
361 * This routine must be called with system_transition_mutex held.
362 */
363int hibernation_snapshot(int platform_mode)
364{
365 pm_message_t msg;
366 int error;
367
368 pm_suspend_clear_flags();
369 error = platform_begin(platform_mode);
370 if (error)
371 goto Close;
372
373 /* Preallocate image memory before shutting down devices. */
374 error = hibernate_preallocate_memory();
375 if (error)
376 goto Close;
377
378 error = freeze_kernel_threads();
379 if (error)
380 goto Cleanup;
381
382 if (hibernation_test(TEST_FREEZER)) {
383
384 /*
385 * Indicate to the caller that we are returning due to a
386 * successful freezer test.
387 */
388 freezer_test_done = true;
389 goto Thaw;
390 }
391
392 error = dpm_prepare(PMSG_FREEZE);
393 if (error) {
394 dpm_complete(PMSG_RECOVER);
395 goto Thaw;
396 }
397
398 suspend_console();
399 pm_restrict_gfp_mask();
400
401 error = dpm_suspend(PMSG_FREEZE);
402
403 if (error || hibernation_test(TEST_DEVICES))
404 platform_recover(platform_mode);
405 else
406 error = create_image(platform_mode);
407
408 /*
409 * In the case that we call create_image() above, the control
410 * returns here (1) after the image has been created or the
411 * image creation has failed and (2) after a successful restore.
412 */
413
414 /* We may need to release the preallocated image pages here. */
415 if (error || !in_suspend)
416 swsusp_free();
417
418 msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
419 dpm_resume(msg);
420
421 if (error || !in_suspend)
422 pm_restore_gfp_mask();
423
424 resume_console();
425 dpm_complete(msg);
426
427 Close:
428 platform_end(platform_mode);
429 return error;
430
431 Thaw:
432 thaw_kernel_threads();
433 Cleanup:
434 swsusp_free();
435 goto Close;
436}
437
438int __weak hibernate_resume_nonboot_cpu_disable(void)
439{
440 return suspend_disable_secondary_cpus();
441}
442
443/**
444 * resume_target_kernel - Restore system state from a hibernation image.
445 * @platform_mode: Whether or not to use the platform driver.
446 *
447 * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
448 * contents of highmem that have not been restored yet from the image and run
449 * the low-level code that will restore the remaining contents of memory and
450 * switch to the just restored target kernel.
451 */
452static int resume_target_kernel(bool platform_mode)
453{
454 int error;
455
456 error = dpm_suspend_end(PMSG_QUIESCE);
457 if (error) {
458 pr_err("Some devices failed to power down, aborting resume\n");
459 return error;
460 }
461
462 error = platform_pre_restore(platform_mode);
463 if (error)
464 goto Cleanup;
465
466 error = hibernate_resume_nonboot_cpu_disable();
467 if (error)
468 goto Enable_cpus;
469
470 local_irq_disable();
471 system_state = SYSTEM_SUSPEND;
472
473 error = syscore_suspend();
474 if (error)
475 goto Enable_irqs;
476
477 save_processor_state();
478 error = restore_highmem();
479 if (!error) {
480 error = swsusp_arch_resume();
481 /*
482 * The code below is only ever reached in case of a failure.
483 * Otherwise, execution continues at the place where
484 * swsusp_arch_suspend() was called.
485 */
486 BUG_ON(!error);
487 /*
488 * This call to restore_highmem() reverts the changes made by
489 * the previous one.
490 */
491 restore_highmem();
492 }
493 /*
494 * The only reason why swsusp_arch_resume() can fail is memory being
495 * very tight, so we have to free it as soon as we can to avoid
496 * subsequent failures.
497 */
498 swsusp_free();
499 restore_processor_state();
500 touch_softlockup_watchdog();
501
502 syscore_resume();
503
504 Enable_irqs:
505 system_state = SYSTEM_RUNNING;
506 local_irq_enable();
507
508 Enable_cpus:
509 suspend_enable_secondary_cpus();
510
511 Cleanup:
512 platform_restore_cleanup(platform_mode);
513
514 dpm_resume_start(PMSG_RECOVER);
515
516 return error;
517}
518
519/**
520 * hibernation_restore - Quiesce devices and restore from a hibernation image.
521 * @platform_mode: If set, use platform driver to prepare for the transition.
522 *
523 * This routine must be called with system_transition_mutex held. If it is
524 * successful, control reappears in the restored target kernel in
525 * hibernation_snapshot().
526 */
527int hibernation_restore(int platform_mode)
528{
529 int error;
530
531 pm_prepare_console();
532 suspend_console();
533 pm_restrict_gfp_mask();
534 error = dpm_suspend_start(PMSG_QUIESCE);
535 if (!error) {
536 error = resume_target_kernel(platform_mode);
537 /*
538 * The above should either succeed and jump to the new kernel,
539 * or return with an error. Otherwise things are just
540 * undefined, so let's be paranoid.
541 */
542 BUG_ON(!error);
543 }
544 dpm_resume_end(PMSG_RECOVER);
545 pm_restore_gfp_mask();
546 resume_console();
547 pm_restore_console();
548 return error;
549}
550
551/**
552 * hibernation_platform_enter - Power off the system using the platform driver.
553 */
554int hibernation_platform_enter(void)
555{
556 int error;
557
558 if (!hibernation_ops)
559 return -ENOSYS;
560
561 /*
562 * We have cancelled the power transition by running
563 * hibernation_ops->finish() before saving the image, so we should let
564 * the firmware know that we're going to enter the sleep state after all
565 */
566 error = hibernation_ops->begin(PMSG_HIBERNATE);
567 if (error)
568 goto Close;
569
570 entering_platform_hibernation = true;
571 suspend_console();
572 error = dpm_suspend_start(PMSG_HIBERNATE);
573 if (error) {
574 if (hibernation_ops->recover)
575 hibernation_ops->recover();
576 goto Resume_devices;
577 }
578
579 error = dpm_suspend_end(PMSG_HIBERNATE);
580 if (error)
581 goto Resume_devices;
582
583 error = hibernation_ops->prepare();
584 if (error)
585 goto Platform_finish;
586
587 error = suspend_disable_secondary_cpus();
588 if (error)
589 goto Enable_cpus;
590
591 local_irq_disable();
592 system_state = SYSTEM_SUSPEND;
593 syscore_suspend();
594 if (pm_wakeup_pending()) {
595 error = -EAGAIN;
596 goto Power_up;
597 }
598
599 hibernation_ops->enter();
600 /* We should never get here */
601 while (1);
602
603 Power_up:
604 syscore_resume();
605 system_state = SYSTEM_RUNNING;
606 local_irq_enable();
607
608 Enable_cpus:
609 suspend_enable_secondary_cpus();
610
611 Platform_finish:
612 hibernation_ops->finish();
613
614 dpm_resume_start(PMSG_RESTORE);
615
616 Resume_devices:
617 entering_platform_hibernation = false;
618 dpm_resume_end(PMSG_RESTORE);
619 resume_console();
620
621 Close:
622 hibernation_ops->end();
623
624 return error;
625}
626
627/**
628 * power_down - Shut the machine down for hibernation.
629 *
630 * Use the platform driver, if configured, to put the system into the sleep
631 * state corresponding to hibernation, or try to power it off or reboot,
632 * depending on the value of hibernation_mode.
633 */
634static void power_down(void)
635{
636#ifdef CONFIG_SUSPEND
637 int error;
638
639 if (hibernation_mode == HIBERNATION_SUSPEND) {
640 error = suspend_devices_and_enter(PM_SUSPEND_MEM);
641 if (error) {
642 hibernation_mode = hibernation_ops ?
643 HIBERNATION_PLATFORM :
644 HIBERNATION_SHUTDOWN;
645 } else {
646 /* Restore swap signature. */
647 error = swsusp_unmark();
648 if (error)
649 pr_err("Swap will be unusable! Try swapon -a.\n");
650
651 return;
652 }
653 }
654#endif
655
656 switch (hibernation_mode) {
657 case HIBERNATION_REBOOT:
658 kernel_restart(NULL);
659 break;
660 case HIBERNATION_PLATFORM:
661 hibernation_platform_enter();
662 fallthrough;
663 case HIBERNATION_SHUTDOWN:
664 if (pm_power_off)
665 kernel_power_off();
666 break;
667 }
668 kernel_halt();
669 /*
670 * Valid image is on the disk, if we continue we risk serious data
671 * corruption after resume.
672 */
673 pr_crit("Power down manually\n");
674 while (1)
675 cpu_relax();
676}
677
678static int load_image_and_restore(void)
679{
680 int error;
681 unsigned int flags;
682
683 pm_pr_dbg("Loading hibernation image.\n");
684
685 lock_device_hotplug();
686 error = create_basic_memory_bitmaps();
687 if (error)
688 goto Unlock;
689
690 error = swsusp_read(&flags);
691 swsusp_close(FMODE_READ);
692 if (!error)
693 error = hibernation_restore(flags & SF_PLATFORM_MODE);
694
695 pr_err("Failed to load image, recovering.\n");
696 swsusp_free();
697 free_basic_memory_bitmaps();
698 Unlock:
699 unlock_device_hotplug();
700
701 return error;
702}
703
704/**
705 * hibernate - Carry out system hibernation, including saving the image.
706 */
707int hibernate(void)
708{
709 int error, nr_calls = 0;
710 bool snapshot_test = false;
711
712 if (!hibernation_available()) {
713 pm_pr_dbg("Hibernation not available.\n");
714 return -EPERM;
715 }
716
717 lock_system_sleep();
718 /* The snapshot device should not be opened while we're running */
719 if (!hibernate_acquire()) {
720 error = -EBUSY;
721 goto Unlock;
722 }
723
724 pr_info("hibernation entry\n");
725 pm_prepare_console();
726 error = __pm_notifier_call_chain(PM_HIBERNATION_PREPARE, -1, &nr_calls);
727 if (error) {
728 nr_calls--;
729 goto Exit;
730 }
731
732 ksys_sync_helper();
733
734 error = freeze_processes();
735 if (error)
736 goto Exit;
737
738 lock_device_hotplug();
739 /* Allocate memory management structures */
740 error = create_basic_memory_bitmaps();
741 if (error)
742 goto Thaw;
743
744 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
745 if (error || freezer_test_done)
746 goto Free_bitmaps;
747
748 if (in_suspend) {
749 unsigned int flags = 0;
750
751 if (hibernation_mode == HIBERNATION_PLATFORM)
752 flags |= SF_PLATFORM_MODE;
753 if (nocompress)
754 flags |= SF_NOCOMPRESS_MODE;
755 else
756 flags |= SF_CRC32_MODE;
757
758 pm_pr_dbg("Writing hibernation image.\n");
759 error = swsusp_write(flags);
760 swsusp_free();
761 if (!error) {
762 if (hibernation_mode == HIBERNATION_TEST_RESUME)
763 snapshot_test = true;
764 else
765 power_down();
766 }
767 in_suspend = 0;
768 pm_restore_gfp_mask();
769 } else {
770 pm_pr_dbg("Hibernation image restored successfully.\n");
771 }
772
773 Free_bitmaps:
774 free_basic_memory_bitmaps();
775 Thaw:
776 unlock_device_hotplug();
777 if (snapshot_test) {
778 pm_pr_dbg("Checking hibernation image\n");
779 error = swsusp_check();
780 if (!error)
781 error = load_image_and_restore();
782 }
783 thaw_processes();
784
785 /* Don't bother checking whether freezer_test_done is true */
786 freezer_test_done = false;
787 Exit:
788 __pm_notifier_call_chain(PM_POST_HIBERNATION, nr_calls, NULL);
789 pm_restore_console();
790 hibernate_release();
791 Unlock:
792 unlock_system_sleep();
793 pr_info("hibernation exit\n");
794
795 return error;
796}
797
798/**
799 * hibernate_quiet_exec - Execute a function with all devices frozen.
800 * @func: Function to execute.
801 * @data: Data pointer to pass to @func.
802 *
803 * Return the @func return value or an error code if it cannot be executed.
804 */
805int hibernate_quiet_exec(int (*func)(void *data), void *data)
806{
807 int error, nr_calls = 0;
808
809 lock_system_sleep();
810
811 if (!hibernate_acquire()) {
812 error = -EBUSY;
813 goto unlock;
814 }
815
816 pm_prepare_console();
817
818 error = __pm_notifier_call_chain(PM_HIBERNATION_PREPARE, -1, &nr_calls);
819 if (error) {
820 nr_calls--;
821 goto exit;
822 }
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, nr_calls, NULL);
884
885 pm_restore_console();
886
887 hibernate_release();
888
889unlock:
890 unlock_system_sleep();
891
892 return error;
893}
894EXPORT_SYMBOL_GPL(hibernate_quiet_exec);
895
896/**
897 * software_resume - Resume from a saved hibernation image.
898 *
899 * This routine is called as a late initcall, when all devices have been
900 * discovered and initialized already.
901 *
902 * The image reading code is called to see if there is a hibernation image
903 * available for reading. If that is the case, devices are quiesced and the
904 * contents of memory is restored from the saved image.
905 *
906 * If this is successful, control reappears in the restored target kernel in
907 * hibernation_snapshot() which returns to hibernate(). Otherwise, the routine
908 * attempts to recover gracefully and make the kernel return to the normal mode
909 * of operation.
910 */
911static int software_resume(void)
912{
913 int error, nr_calls = 0;
914
915 /*
916 * If the user said "noresume".. bail out early.
917 */
918 if (noresume || !hibernation_available())
919 return 0;
920
921 /*
922 * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
923 * is configured into the kernel. Since the regular hibernate
924 * trigger path is via sysfs which takes a buffer mutex before
925 * calling hibernate functions (which take system_transition_mutex)
926 * this can cause lockdep to complain about a possible ABBA deadlock
927 * which cannot happen since we're in the boot code here and
928 * sysfs can't be invoked yet. Therefore, we use a subclass
929 * here to avoid lockdep complaining.
930 */
931 mutex_lock_nested(&system_transition_mutex, SINGLE_DEPTH_NESTING);
932
933 if (swsusp_resume_device)
934 goto Check_image;
935
936 if (!strlen(resume_file)) {
937 error = -ENOENT;
938 goto Unlock;
939 }
940
941 pm_pr_dbg("Checking hibernation image partition %s\n", resume_file);
942
943 if (resume_delay) {
944 pr_info("Waiting %dsec before reading resume device ...\n",
945 resume_delay);
946 ssleep(resume_delay);
947 }
948
949 /* Check if the device is there */
950 swsusp_resume_device = name_to_dev_t(resume_file);
951
952 /*
953 * name_to_dev_t is ineffective to verify parition if resume_file is in
954 * integer format. (e.g. major:minor)
955 */
956 if (isdigit(resume_file[0]) && resume_wait) {
957 int partno;
958 while (!get_gendisk(swsusp_resume_device, &partno))
959 msleep(10);
960 }
961
962 if (!swsusp_resume_device) {
963 /*
964 * Some device discovery might still be in progress; we need
965 * to wait for this to finish.
966 */
967 wait_for_device_probe();
968
969 if (resume_wait) {
970 while ((swsusp_resume_device = name_to_dev_t(resume_file)) == 0)
971 msleep(10);
972 async_synchronize_full();
973 }
974
975 swsusp_resume_device = name_to_dev_t(resume_file);
976 if (!swsusp_resume_device) {
977 error = -ENODEV;
978 goto Unlock;
979 }
980 }
981
982 Check_image:
983 pm_pr_dbg("Hibernation image partition %d:%d present\n",
984 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
985
986 pm_pr_dbg("Looking for hibernation image.\n");
987 error = swsusp_check();
988 if (error)
989 goto Unlock;
990
991 /* The snapshot device should not be opened while we're running */
992 if (!hibernate_acquire()) {
993 error = -EBUSY;
994 swsusp_close(FMODE_READ);
995 goto Unlock;
996 }
997
998 pr_info("resume from hibernation\n");
999 pm_prepare_console();
1000 error = __pm_notifier_call_chain(PM_RESTORE_PREPARE, -1, &nr_calls);
1001 if (error) {
1002 nr_calls--;
1003 goto Close_Finish;
1004 }
1005
1006 pm_pr_dbg("Preparing processes for hibernation restore.\n");
1007 error = freeze_processes();
1008 if (error)
1009 goto Close_Finish;
1010
1011 error = freeze_kernel_threads();
1012 if (error) {
1013 thaw_processes();
1014 goto Close_Finish;
1015 }
1016
1017 error = load_image_and_restore();
1018 thaw_processes();
1019 Finish:
1020 __pm_notifier_call_chain(PM_POST_RESTORE, nr_calls, NULL);
1021 pm_restore_console();
1022 pr_info("resume failed (%d)\n", error);
1023 hibernate_release();
1024 /* For success case, the suspend path will release the lock */
1025 Unlock:
1026 mutex_unlock(&system_transition_mutex);
1027 pm_pr_dbg("Hibernation image not present or could not be loaded.\n");
1028 return error;
1029 Close_Finish:
1030 swsusp_close(FMODE_READ);
1031 goto Finish;
1032}
1033
1034late_initcall_sync(software_resume);
1035
1036
1037static const char * const hibernation_modes[] = {
1038 [HIBERNATION_PLATFORM] = "platform",
1039 [HIBERNATION_SHUTDOWN] = "shutdown",
1040 [HIBERNATION_REBOOT] = "reboot",
1041#ifdef CONFIG_SUSPEND
1042 [HIBERNATION_SUSPEND] = "suspend",
1043#endif
1044 [HIBERNATION_TEST_RESUME] = "test_resume",
1045};
1046
1047/*
1048 * /sys/power/disk - Control hibernation mode.
1049 *
1050 * Hibernation can be handled in several ways. There are a few different ways
1051 * to put the system into the sleep state: using the platform driver (e.g. ACPI
1052 * or other hibernation_ops), powering it off or rebooting it (for testing
1053 * mostly).
1054 *
1055 * The sysfs file /sys/power/disk provides an interface for selecting the
1056 * hibernation mode to use. Reading from this file causes the available modes
1057 * to be printed. There are 3 modes that can be supported:
1058 *
1059 * 'platform'
1060 * 'shutdown'
1061 * 'reboot'
1062 *
1063 * If a platform hibernation driver is in use, 'platform' will be supported
1064 * and will be used by default. Otherwise, 'shutdown' will be used by default.
1065 * The selected option (i.e. the one corresponding to the current value of
1066 * hibernation_mode) is enclosed by a square bracket.
1067 *
1068 * To select a given hibernation mode it is necessary to write the mode's
1069 * string representation (as returned by reading from /sys/power/disk) back
1070 * into /sys/power/disk.
1071 */
1072
1073static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
1074 char *buf)
1075{
1076 int i;
1077 char *start = buf;
1078
1079 if (!hibernation_available())
1080 return sprintf(buf, "[disabled]\n");
1081
1082 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
1083 if (!hibernation_modes[i])
1084 continue;
1085 switch (i) {
1086 case HIBERNATION_SHUTDOWN:
1087 case HIBERNATION_REBOOT:
1088#ifdef CONFIG_SUSPEND
1089 case HIBERNATION_SUSPEND:
1090#endif
1091 case HIBERNATION_TEST_RESUME:
1092 break;
1093 case HIBERNATION_PLATFORM:
1094 if (hibernation_ops)
1095 break;
1096 /* not a valid mode, continue with loop */
1097 continue;
1098 }
1099 if (i == hibernation_mode)
1100 buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
1101 else
1102 buf += sprintf(buf, "%s ", hibernation_modes[i]);
1103 }
1104 buf += sprintf(buf, "\n");
1105 return buf-start;
1106}
1107
1108static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
1109 const char *buf, size_t n)
1110{
1111 int error = 0;
1112 int i;
1113 int len;
1114 char *p;
1115 int mode = HIBERNATION_INVALID;
1116
1117 if (!hibernation_available())
1118 return -EPERM;
1119
1120 p = memchr(buf, '\n', n);
1121 len = p ? p - buf : n;
1122
1123 lock_system_sleep();
1124 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
1125 if (len == strlen(hibernation_modes[i])
1126 && !strncmp(buf, hibernation_modes[i], len)) {
1127 mode = i;
1128 break;
1129 }
1130 }
1131 if (mode != HIBERNATION_INVALID) {
1132 switch (mode) {
1133 case HIBERNATION_SHUTDOWN:
1134 case HIBERNATION_REBOOT:
1135#ifdef CONFIG_SUSPEND
1136 case HIBERNATION_SUSPEND:
1137#endif
1138 case HIBERNATION_TEST_RESUME:
1139 hibernation_mode = mode;
1140 break;
1141 case HIBERNATION_PLATFORM:
1142 if (hibernation_ops)
1143 hibernation_mode = mode;
1144 else
1145 error = -EINVAL;
1146 }
1147 } else
1148 error = -EINVAL;
1149
1150 if (!error)
1151 pm_pr_dbg("Hibernation mode set to '%s'\n",
1152 hibernation_modes[mode]);
1153 unlock_system_sleep();
1154 return error ? error : n;
1155}
1156
1157power_attr(disk);
1158
1159static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
1160 char *buf)
1161{
1162 return sprintf(buf, "%d:%d\n", MAJOR(swsusp_resume_device),
1163 MINOR(swsusp_resume_device));
1164}
1165
1166static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
1167 const char *buf, size_t n)
1168{
1169 dev_t res;
1170 int len = n;
1171 char *name;
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 lock_system_sleep();
1185 swsusp_resume_device = res;
1186 unlock_system_sleep();
1187 pm_pr_dbg("Configured hibernation resume from disk to %u\n",
1188 swsusp_resume_device);
1189 noresume = 0;
1190 software_resume();
1191 return n;
1192}
1193
1194power_attr(resume);
1195
1196static ssize_t resume_offset_show(struct kobject *kobj,
1197 struct kobj_attribute *attr, char *buf)
1198{
1199 return sprintf(buf, "%llu\n", (unsigned long long)swsusp_resume_block);
1200}
1201
1202static ssize_t resume_offset_store(struct kobject *kobj,
1203 struct kobj_attribute *attr, const char *buf,
1204 size_t n)
1205{
1206 unsigned long long offset;
1207 int rc;
1208
1209 rc = kstrtoull(buf, 0, &offset);
1210 if (rc)
1211 return rc;
1212 swsusp_resume_block = offset;
1213
1214 return n;
1215}
1216
1217power_attr(resume_offset);
1218
1219static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
1220 char *buf)
1221{
1222 return sprintf(buf, "%lu\n", image_size);
1223}
1224
1225static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
1226 const char *buf, size_t n)
1227{
1228 unsigned long size;
1229
1230 if (sscanf(buf, "%lu", &size) == 1) {
1231 image_size = size;
1232 return n;
1233 }
1234
1235 return -EINVAL;
1236}
1237
1238power_attr(image_size);
1239
1240static ssize_t reserved_size_show(struct kobject *kobj,
1241 struct kobj_attribute *attr, char *buf)
1242{
1243 return sprintf(buf, "%lu\n", reserved_size);
1244}
1245
1246static ssize_t reserved_size_store(struct kobject *kobj,
1247 struct kobj_attribute *attr,
1248 const char *buf, size_t n)
1249{
1250 unsigned long size;
1251
1252 if (sscanf(buf, "%lu", &size) == 1) {
1253 reserved_size = size;
1254 return n;
1255 }
1256
1257 return -EINVAL;
1258}
1259
1260power_attr(reserved_size);
1261
1262static struct attribute *g[] = {
1263 &disk_attr.attr,
1264 &resume_offset_attr.attr,
1265 &resume_attr.attr,
1266 &image_size_attr.attr,
1267 &reserved_size_attr.attr,
1268 NULL,
1269};
1270
1271
1272static const struct attribute_group attr_group = {
1273 .attrs = g,
1274};
1275
1276
1277static int __init pm_disk_init(void)
1278{
1279 return sysfs_create_group(power_kobj, &attr_group);
1280}
1281
1282core_initcall(pm_disk_init);
1283
1284
1285static int __init resume_setup(char *str)
1286{
1287 if (noresume)
1288 return 1;
1289
1290 strncpy(resume_file, str, 255);
1291 return 1;
1292}
1293
1294static int __init resume_offset_setup(char *str)
1295{
1296 unsigned long long offset;
1297
1298 if (noresume)
1299 return 1;
1300
1301 if (sscanf(str, "%llu", &offset) == 1)
1302 swsusp_resume_block = offset;
1303
1304 return 1;
1305}
1306
1307static int __init hibernate_setup(char *str)
1308{
1309 if (!strncmp(str, "noresume", 8)) {
1310 noresume = 1;
1311 } else if (!strncmp(str, "nocompress", 10)) {
1312 nocompress = 1;
1313 } else if (!strncmp(str, "no", 2)) {
1314 noresume = 1;
1315 nohibernate = 1;
1316 } else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)
1317 && !strncmp(str, "protect_image", 13)) {
1318 enable_restore_image_protection();
1319 }
1320 return 1;
1321}
1322
1323static int __init noresume_setup(char *str)
1324{
1325 noresume = 1;
1326 return 1;
1327}
1328
1329static int __init resumewait_setup(char *str)
1330{
1331 resume_wait = 1;
1332 return 1;
1333}
1334
1335static int __init resumedelay_setup(char *str)
1336{
1337 int rc = kstrtouint(str, 0, &resume_delay);
1338
1339 if (rc)
1340 return rc;
1341 return 1;
1342}
1343
1344static int __init nohibernate_setup(char *str)
1345{
1346 noresume = 1;
1347 nohibernate = 1;
1348 return 1;
1349}
1350
1351__setup("noresume", noresume_setup);
1352__setup("resume_offset=", resume_offset_setup);
1353__setup("resume=", resume_setup);
1354__setup("hibernate=", hibernate_setup);
1355__setup("resumewait", resumewait_setup);
1356__setup("resumedelay=", resumedelay_setup);
1357__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/blkdev.h>
15#include <linux/export.h>
16#include <linux/suspend.h>
17#include <linux/reboot.h>
18#include <linux/string.h>
19#include <linux/device.h>
20#include <linux/async.h>
21#include <linux/delay.h>
22#include <linux/fs.h>
23#include <linux/mount.h>
24#include <linux/pm.h>
25#include <linux/nmi.h>
26#include <linux/console.h>
27#include <linux/cpu.h>
28#include <linux/freezer.h>
29#include <linux/gfp.h>
30#include <linux/syscore_ops.h>
31#include <linux/ctype.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() && !cxl_mem_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 unsigned int sleep_flags;
97
98 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
99 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
100 && ops->restore_cleanup && ops->leave)) {
101 WARN_ON(1);
102 return;
103 }
104
105 sleep_flags = lock_system_sleep();
106
107 hibernation_ops = ops;
108 if (ops)
109 hibernation_mode = HIBERNATION_PLATFORM;
110 else if (hibernation_mode == HIBERNATION_PLATFORM)
111 hibernation_mode = HIBERNATION_SHUTDOWN;
112
113 unlock_system_sleep(sleep_flags);
114}
115EXPORT_SYMBOL_GPL(hibernation_set_ops);
116
117static bool entering_platform_hibernation;
118
119bool system_entering_hibernation(void)
120{
121 return entering_platform_hibernation;
122}
123EXPORT_SYMBOL(system_entering_hibernation);
124
125#ifdef CONFIG_PM_DEBUG
126static void hibernation_debug_sleep(void)
127{
128 pr_info("debug: Waiting for 5 seconds.\n");
129 mdelay(5000);
130}
131
132static int hibernation_test(int level)
133{
134 if (pm_test_level == level) {
135 hibernation_debug_sleep();
136 return 1;
137 }
138 return 0;
139}
140#else /* !CONFIG_PM_DEBUG */
141static int hibernation_test(int level) { return 0; }
142#endif /* !CONFIG_PM_DEBUG */
143
144/**
145 * platform_begin - Call platform to start hibernation.
146 * @platform_mode: Whether or not to use the platform driver.
147 */
148static int platform_begin(int platform_mode)
149{
150 return (platform_mode && hibernation_ops) ?
151 hibernation_ops->begin(PMSG_FREEZE) : 0;
152}
153
154/**
155 * platform_end - Call platform to finish transition to the working state.
156 * @platform_mode: Whether or not to use the platform driver.
157 */
158static void platform_end(int platform_mode)
159{
160 if (platform_mode && hibernation_ops)
161 hibernation_ops->end();
162}
163
164/**
165 * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
166 * @platform_mode: Whether or not to use the platform driver.
167 *
168 * Use the platform driver to prepare the system for creating a hibernate image,
169 * if so configured, and return an error code if that fails.
170 */
171
172static int platform_pre_snapshot(int platform_mode)
173{
174 return (platform_mode && hibernation_ops) ?
175 hibernation_ops->pre_snapshot() : 0;
176}
177
178/**
179 * platform_leave - Call platform to prepare a transition to the working state.
180 * @platform_mode: Whether or not to use the platform driver.
181 *
182 * Use the platform driver prepare to prepare the machine for switching to the
183 * normal mode of operation.
184 *
185 * This routine is called on one CPU with interrupts disabled.
186 */
187static void platform_leave(int platform_mode)
188{
189 if (platform_mode && hibernation_ops)
190 hibernation_ops->leave();
191}
192
193/**
194 * platform_finish - Call platform to switch the system to the working state.
195 * @platform_mode: Whether or not to use the platform driver.
196 *
197 * Use the platform driver to switch the machine to the normal mode of
198 * operation.
199 *
200 * This routine must be called after platform_prepare().
201 */
202static void platform_finish(int platform_mode)
203{
204 if (platform_mode && hibernation_ops)
205 hibernation_ops->finish();
206}
207
208/**
209 * platform_pre_restore - Prepare for hibernate image restoration.
210 * @platform_mode: Whether or not to use the platform driver.
211 *
212 * Use the platform driver to prepare the system for resume from a hibernation
213 * image.
214 *
215 * If the restore fails after this function has been called,
216 * platform_restore_cleanup() must be called.
217 */
218static int platform_pre_restore(int platform_mode)
219{
220 return (platform_mode && hibernation_ops) ?
221 hibernation_ops->pre_restore() : 0;
222}
223
224/**
225 * platform_restore_cleanup - Switch to the working state after failing restore.
226 * @platform_mode: Whether or not to use the platform driver.
227 *
228 * Use the platform driver to switch the system to the normal mode of operation
229 * after a failing restore.
230 *
231 * If platform_pre_restore() has been called before the failing restore, this
232 * function must be called too, regardless of the result of
233 * platform_pre_restore().
234 */
235static void platform_restore_cleanup(int platform_mode)
236{
237 if (platform_mode && hibernation_ops)
238 hibernation_ops->restore_cleanup();
239}
240
241/**
242 * platform_recover - Recover from a failure to suspend devices.
243 * @platform_mode: Whether or not to use the platform driver.
244 */
245static void platform_recover(int platform_mode)
246{
247 if (platform_mode && hibernation_ops && hibernation_ops->recover)
248 hibernation_ops->recover();
249}
250
251/**
252 * swsusp_show_speed - Print time elapsed between two events during hibernation.
253 * @start: Starting event.
254 * @stop: Final event.
255 * @nr_pages: Number of memory pages processed between @start and @stop.
256 * @msg: Additional diagnostic message to print.
257 */
258void swsusp_show_speed(ktime_t start, ktime_t stop,
259 unsigned nr_pages, char *msg)
260{
261 ktime_t diff;
262 u64 elapsed_centisecs64;
263 unsigned int centisecs;
264 unsigned int k;
265 unsigned int kps;
266
267 diff = ktime_sub(stop, start);
268 elapsed_centisecs64 = ktime_divns(diff, 10*NSEC_PER_MSEC);
269 centisecs = elapsed_centisecs64;
270 if (centisecs == 0)
271 centisecs = 1; /* avoid div-by-zero */
272 k = nr_pages * (PAGE_SIZE / 1024);
273 kps = (k * 100) / centisecs;
274 pr_info("%s %u kbytes in %u.%02u seconds (%u.%02u MB/s)\n",
275 msg, k, centisecs / 100, centisecs % 100, kps / 1000,
276 (kps % 1000) / 10);
277}
278
279__weak int arch_resume_nosmt(void)
280{
281 return 0;
282}
283
284/**
285 * create_image - Create a hibernation image.
286 * @platform_mode: Whether or not to use the platform driver.
287 *
288 * Execute device drivers' "late" and "noirq" freeze callbacks, create a
289 * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
290 *
291 * Control reappears in this routine after the subsequent restore.
292 */
293static int create_image(int platform_mode)
294{
295 int error;
296
297 error = dpm_suspend_end(PMSG_FREEZE);
298 if (error) {
299 pr_err("Some devices failed to power down, aborting\n");
300 return error;
301 }
302
303 error = platform_pre_snapshot(platform_mode);
304 if (error || hibernation_test(TEST_PLATFORM))
305 goto Platform_finish;
306
307 error = pm_sleep_disable_secondary_cpus();
308 if (error || hibernation_test(TEST_CPUS))
309 goto Enable_cpus;
310
311 local_irq_disable();
312
313 system_state = SYSTEM_SUSPEND;
314
315 error = syscore_suspend();
316 if (error) {
317 pr_err("Some system devices failed to power down, aborting\n");
318 goto Enable_irqs;
319 }
320
321 if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
322 goto Power_up;
323
324 in_suspend = 1;
325 save_processor_state();
326 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true);
327 error = swsusp_arch_suspend();
328 /* Restore control flow magically appears here */
329 restore_processor_state();
330 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false);
331 if (error)
332 pr_err("Error %d creating image\n", error);
333
334 if (!in_suspend) {
335 events_check_enabled = false;
336 clear_or_poison_free_pages();
337 }
338
339 platform_leave(platform_mode);
340
341 Power_up:
342 syscore_resume();
343
344 Enable_irqs:
345 system_state = SYSTEM_RUNNING;
346 local_irq_enable();
347
348 Enable_cpus:
349 pm_sleep_enable_secondary_cpus();
350
351 /* Allow architectures to do nosmt-specific post-resume dances */
352 if (!in_suspend)
353 error = arch_resume_nosmt();
354
355 Platform_finish:
356 platform_finish(platform_mode);
357
358 dpm_resume_start(in_suspend ?
359 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
360
361 return error;
362}
363
364/**
365 * hibernation_snapshot - Quiesce devices and create a hibernation image.
366 * @platform_mode: If set, use platform driver to prepare for the transition.
367 *
368 * This routine must be called with system_transition_mutex held.
369 */
370int hibernation_snapshot(int platform_mode)
371{
372 pm_message_t msg;
373 int error;
374
375 pm_suspend_clear_flags();
376 error = platform_begin(platform_mode);
377 if (error)
378 goto Close;
379
380 /* Preallocate image memory before shutting down devices. */
381 error = hibernate_preallocate_memory();
382 if (error)
383 goto Close;
384
385 error = freeze_kernel_threads();
386 if (error)
387 goto Cleanup;
388
389 if (hibernation_test(TEST_FREEZER)) {
390
391 /*
392 * Indicate to the caller that we are returning due to a
393 * successful freezer test.
394 */
395 freezer_test_done = true;
396 goto Thaw;
397 }
398
399 error = dpm_prepare(PMSG_FREEZE);
400 if (error) {
401 dpm_complete(PMSG_RECOVER);
402 goto Thaw;
403 }
404
405 suspend_console();
406 pm_restrict_gfp_mask();
407
408 error = dpm_suspend(PMSG_FREEZE);
409
410 if (error || hibernation_test(TEST_DEVICES))
411 platform_recover(platform_mode);
412 else
413 error = create_image(platform_mode);
414
415 /*
416 * In the case that we call create_image() above, the control
417 * returns here (1) after the image has been created or the
418 * image creation has failed and (2) after a successful restore.
419 */
420
421 /* We may need to release the preallocated image pages here. */
422 if (error || !in_suspend)
423 swsusp_free();
424
425 msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
426 dpm_resume(msg);
427
428 if (error || !in_suspend)
429 pm_restore_gfp_mask();
430
431 resume_console();
432 dpm_complete(msg);
433
434 Close:
435 platform_end(platform_mode);
436 return error;
437
438 Thaw:
439 thaw_kernel_threads();
440 Cleanup:
441 swsusp_free();
442 goto Close;
443}
444
445int __weak hibernate_resume_nonboot_cpu_disable(void)
446{
447 return suspend_disable_secondary_cpus();
448}
449
450/**
451 * resume_target_kernel - Restore system state from a hibernation image.
452 * @platform_mode: Whether or not to use the platform driver.
453 *
454 * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
455 * contents of highmem that have not been restored yet from the image and run
456 * the low-level code that will restore the remaining contents of memory and
457 * switch to the just restored target kernel.
458 */
459static int resume_target_kernel(bool platform_mode)
460{
461 int error;
462
463 error = dpm_suspend_end(PMSG_QUIESCE);
464 if (error) {
465 pr_err("Some devices failed to power down, aborting resume\n");
466 return error;
467 }
468
469 error = platform_pre_restore(platform_mode);
470 if (error)
471 goto Cleanup;
472
473 cpuidle_pause();
474
475 error = hibernate_resume_nonboot_cpu_disable();
476 if (error)
477 goto Enable_cpus;
478
479 local_irq_disable();
480 system_state = SYSTEM_SUSPEND;
481
482 error = syscore_suspend();
483 if (error)
484 goto Enable_irqs;
485
486 save_processor_state();
487 error = restore_highmem();
488 if (!error) {
489 error = swsusp_arch_resume();
490 /*
491 * The code below is only ever reached in case of a failure.
492 * Otherwise, execution continues at the place where
493 * swsusp_arch_suspend() was called.
494 */
495 BUG_ON(!error);
496 /*
497 * This call to restore_highmem() reverts the changes made by
498 * the previous one.
499 */
500 restore_highmem();
501 }
502 /*
503 * The only reason why swsusp_arch_resume() can fail is memory being
504 * very tight, so we have to free it as soon as we can to avoid
505 * subsequent failures.
506 */
507 swsusp_free();
508 restore_processor_state();
509 touch_softlockup_watchdog();
510
511 syscore_resume();
512
513 Enable_irqs:
514 system_state = SYSTEM_RUNNING;
515 local_irq_enable();
516
517 Enable_cpus:
518 pm_sleep_enable_secondary_cpus();
519
520 Cleanup:
521 platform_restore_cleanup(platform_mode);
522
523 dpm_resume_start(PMSG_RECOVER);
524
525 return error;
526}
527
528/**
529 * hibernation_restore - Quiesce devices and restore from a hibernation image.
530 * @platform_mode: If set, use platform driver to prepare for the transition.
531 *
532 * This routine must be called with system_transition_mutex held. If it is
533 * successful, control reappears in the restored target kernel in
534 * hibernation_snapshot().
535 */
536int hibernation_restore(int platform_mode)
537{
538 int error;
539
540 pm_prepare_console();
541 suspend_console();
542 pm_restrict_gfp_mask();
543 error = dpm_suspend_start(PMSG_QUIESCE);
544 if (!error) {
545 error = resume_target_kernel(platform_mode);
546 /*
547 * The above should either succeed and jump to the new kernel,
548 * or return with an error. Otherwise things are just
549 * undefined, so let's be paranoid.
550 */
551 BUG_ON(!error);
552 }
553 dpm_resume_end(PMSG_RECOVER);
554 pm_restore_gfp_mask();
555 resume_console();
556 pm_restore_console();
557 return error;
558}
559
560/**
561 * hibernation_platform_enter - Power off the system using the platform driver.
562 */
563int hibernation_platform_enter(void)
564{
565 int error;
566
567 if (!hibernation_ops)
568 return -ENOSYS;
569
570 /*
571 * We have cancelled the power transition by running
572 * hibernation_ops->finish() before saving the image, so we should let
573 * the firmware know that we're going to enter the sleep state after all
574 */
575 error = hibernation_ops->begin(PMSG_HIBERNATE);
576 if (error)
577 goto Close;
578
579 entering_platform_hibernation = true;
580 suspend_console();
581 error = dpm_suspend_start(PMSG_HIBERNATE);
582 if (error) {
583 if (hibernation_ops->recover)
584 hibernation_ops->recover();
585 goto Resume_devices;
586 }
587
588 error = dpm_suspend_end(PMSG_HIBERNATE);
589 if (error)
590 goto Resume_devices;
591
592 error = hibernation_ops->prepare();
593 if (error)
594 goto Platform_finish;
595
596 error = pm_sleep_disable_secondary_cpus();
597 if (error)
598 goto Enable_cpus;
599
600 local_irq_disable();
601 system_state = SYSTEM_SUSPEND;
602 syscore_suspend();
603 if (pm_wakeup_pending()) {
604 error = -EAGAIN;
605 goto Power_up;
606 }
607
608 hibernation_ops->enter();
609 /* We should never get here */
610 while (1);
611
612 Power_up:
613 syscore_resume();
614 system_state = SYSTEM_RUNNING;
615 local_irq_enable();
616
617 Enable_cpus:
618 pm_sleep_enable_secondary_cpus();
619
620 Platform_finish:
621 hibernation_ops->finish();
622
623 dpm_resume_start(PMSG_RESTORE);
624
625 Resume_devices:
626 entering_platform_hibernation = false;
627 dpm_resume_end(PMSG_RESTORE);
628 resume_console();
629
630 Close:
631 hibernation_ops->end();
632
633 return error;
634}
635
636/**
637 * power_down - Shut the machine down for hibernation.
638 *
639 * Use the platform driver, if configured, to put the system into the sleep
640 * state corresponding to hibernation, or try to power it off or reboot,
641 * depending on the value of hibernation_mode.
642 */
643static void power_down(void)
644{
645 int error;
646
647#ifdef CONFIG_SUSPEND
648 if (hibernation_mode == HIBERNATION_SUSPEND) {
649 error = suspend_devices_and_enter(mem_sleep_current);
650 if (error) {
651 hibernation_mode = hibernation_ops ?
652 HIBERNATION_PLATFORM :
653 HIBERNATION_SHUTDOWN;
654 } else {
655 /* Restore swap signature. */
656 error = swsusp_unmark();
657 if (error)
658 pr_err("Swap will be unusable! Try swapon -a.\n");
659
660 return;
661 }
662 }
663#endif
664
665 switch (hibernation_mode) {
666 case HIBERNATION_REBOOT:
667 kernel_restart(NULL);
668 break;
669 case HIBERNATION_PLATFORM:
670 error = hibernation_platform_enter();
671 if (error == -EAGAIN || error == -EBUSY) {
672 swsusp_unmark();
673 events_check_enabled = false;
674 pr_info("Wakeup event detected during hibernation, rolling back.\n");
675 return;
676 }
677 fallthrough;
678 case HIBERNATION_SHUTDOWN:
679 if (kernel_can_power_off())
680 kernel_power_off();
681 break;
682 }
683 kernel_halt();
684 /*
685 * Valid image is on the disk, if we continue we risk serious data
686 * corruption after resume.
687 */
688 pr_crit("Power down manually\n");
689 while (1)
690 cpu_relax();
691}
692
693static int load_image_and_restore(void)
694{
695 int error;
696 unsigned int flags;
697
698 pm_pr_dbg("Loading hibernation image.\n");
699
700 lock_device_hotplug();
701 error = create_basic_memory_bitmaps();
702 if (error) {
703 swsusp_close();
704 goto Unlock;
705 }
706
707 error = swsusp_read(&flags);
708 swsusp_close();
709 if (!error)
710 error = hibernation_restore(flags & SF_PLATFORM_MODE);
711
712 pr_err("Failed to load image, recovering.\n");
713 swsusp_free();
714 free_basic_memory_bitmaps();
715 Unlock:
716 unlock_device_hotplug();
717
718 return error;
719}
720
721/**
722 * hibernate - Carry out system hibernation, including saving the image.
723 */
724int hibernate(void)
725{
726 bool snapshot_test = false;
727 unsigned int sleep_flags;
728 int error;
729
730 if (!hibernation_available()) {
731 pm_pr_dbg("Hibernation not available.\n");
732 return -EPERM;
733 }
734
735 sleep_flags = lock_system_sleep();
736 /* The snapshot device should not be opened while we're running */
737 if (!hibernate_acquire()) {
738 error = -EBUSY;
739 goto Unlock;
740 }
741
742 pr_info("hibernation entry\n");
743 pm_prepare_console();
744 error = pm_notifier_call_chain_robust(PM_HIBERNATION_PREPARE, PM_POST_HIBERNATION);
745 if (error)
746 goto Restore;
747
748 ksys_sync_helper();
749
750 error = freeze_processes();
751 if (error)
752 goto Exit;
753
754 lock_device_hotplug();
755 /* Allocate memory management structures */
756 error = create_basic_memory_bitmaps();
757 if (error)
758 goto Thaw;
759
760 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
761 if (error || freezer_test_done)
762 goto Free_bitmaps;
763
764 if (in_suspend) {
765 unsigned int flags = 0;
766
767 if (hibernation_mode == HIBERNATION_PLATFORM)
768 flags |= SF_PLATFORM_MODE;
769 if (nocompress)
770 flags |= SF_NOCOMPRESS_MODE;
771 else
772 flags |= SF_CRC32_MODE;
773
774 pm_pr_dbg("Writing hibernation image.\n");
775 error = swsusp_write(flags);
776 swsusp_free();
777 if (!error) {
778 if (hibernation_mode == HIBERNATION_TEST_RESUME)
779 snapshot_test = true;
780 else
781 power_down();
782 }
783 in_suspend = 0;
784 pm_restore_gfp_mask();
785 } else {
786 pm_pr_dbg("Hibernation image restored successfully.\n");
787 }
788
789 Free_bitmaps:
790 free_basic_memory_bitmaps();
791 Thaw:
792 unlock_device_hotplug();
793 if (snapshot_test) {
794 pm_pr_dbg("Checking hibernation image\n");
795 error = swsusp_check(false);
796 if (!error)
797 error = load_image_and_restore();
798 }
799 thaw_processes();
800
801 /* Don't bother checking whether freezer_test_done is true */
802 freezer_test_done = false;
803 Exit:
804 pm_notifier_call_chain(PM_POST_HIBERNATION);
805 Restore:
806 pm_restore_console();
807 hibernate_release();
808 Unlock:
809 unlock_system_sleep(sleep_flags);
810 pr_info("hibernation exit\n");
811
812 return error;
813}
814
815/**
816 * hibernate_quiet_exec - Execute a function with all devices frozen.
817 * @func: Function to execute.
818 * @data: Data pointer to pass to @func.
819 *
820 * Return the @func return value or an error code if it cannot be executed.
821 */
822int hibernate_quiet_exec(int (*func)(void *data), void *data)
823{
824 unsigned int sleep_flags;
825 int error;
826
827 sleep_flags = lock_system_sleep();
828
829 if (!hibernate_acquire()) {
830 error = -EBUSY;
831 goto unlock;
832 }
833
834 pm_prepare_console();
835
836 error = pm_notifier_call_chain_robust(PM_HIBERNATION_PREPARE, PM_POST_HIBERNATION);
837 if (error)
838 goto restore;
839
840 error = freeze_processes();
841 if (error)
842 goto exit;
843
844 lock_device_hotplug();
845
846 pm_suspend_clear_flags();
847
848 error = platform_begin(true);
849 if (error)
850 goto thaw;
851
852 error = freeze_kernel_threads();
853 if (error)
854 goto thaw;
855
856 error = dpm_prepare(PMSG_FREEZE);
857 if (error)
858 goto dpm_complete;
859
860 suspend_console();
861
862 error = dpm_suspend(PMSG_FREEZE);
863 if (error)
864 goto dpm_resume;
865
866 error = dpm_suspend_end(PMSG_FREEZE);
867 if (error)
868 goto dpm_resume;
869
870 error = platform_pre_snapshot(true);
871 if (error)
872 goto skip;
873
874 error = func(data);
875
876skip:
877 platform_finish(true);
878
879 dpm_resume_start(PMSG_THAW);
880
881dpm_resume:
882 dpm_resume(PMSG_THAW);
883
884 resume_console();
885
886dpm_complete:
887 dpm_complete(PMSG_THAW);
888
889 thaw_kernel_threads();
890
891thaw:
892 platform_end(true);
893
894 unlock_device_hotplug();
895
896 thaw_processes();
897
898exit:
899 pm_notifier_call_chain(PM_POST_HIBERNATION);
900
901restore:
902 pm_restore_console();
903
904 hibernate_release();
905
906unlock:
907 unlock_system_sleep(sleep_flags);
908
909 return error;
910}
911EXPORT_SYMBOL_GPL(hibernate_quiet_exec);
912
913static int __init find_resume_device(void)
914{
915 if (!strlen(resume_file))
916 return -ENOENT;
917
918 pm_pr_dbg("Checking hibernation image partition %s\n", resume_file);
919
920 if (resume_delay) {
921 pr_info("Waiting %dsec before reading resume device ...\n",
922 resume_delay);
923 ssleep(resume_delay);
924 }
925
926 /* Check if the device is there */
927 if (!early_lookup_bdev(resume_file, &swsusp_resume_device))
928 return 0;
929
930 /*
931 * Some device discovery might still be in progress; we need to wait for
932 * this to finish.
933 */
934 wait_for_device_probe();
935 if (resume_wait) {
936 while (early_lookup_bdev(resume_file, &swsusp_resume_device))
937 msleep(10);
938 async_synchronize_full();
939 }
940
941 return early_lookup_bdev(resume_file, &swsusp_resume_device);
942}
943
944static int software_resume(void)
945{
946 int error;
947
948 pm_pr_dbg("Hibernation image partition %d:%d present\n",
949 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
950
951 pm_pr_dbg("Looking for hibernation image.\n");
952
953 mutex_lock(&system_transition_mutex);
954 error = swsusp_check(true);
955 if (error)
956 goto Unlock;
957
958 /* The snapshot device should not be opened while we're running */
959 if (!hibernate_acquire()) {
960 error = -EBUSY;
961 swsusp_close();
962 goto Unlock;
963 }
964
965 pr_info("resume from hibernation\n");
966 pm_prepare_console();
967 error = pm_notifier_call_chain_robust(PM_RESTORE_PREPARE, PM_POST_RESTORE);
968 if (error)
969 goto Restore;
970
971 pm_pr_dbg("Preparing processes for hibernation restore.\n");
972 error = freeze_processes();
973 if (error)
974 goto Close_Finish;
975
976 error = freeze_kernel_threads();
977 if (error) {
978 thaw_processes();
979 goto Close_Finish;
980 }
981
982 error = load_image_and_restore();
983 thaw_processes();
984 Finish:
985 pm_notifier_call_chain(PM_POST_RESTORE);
986 Restore:
987 pm_restore_console();
988 pr_info("resume failed (%d)\n", error);
989 hibernate_release();
990 /* For success case, the suspend path will release the lock */
991 Unlock:
992 mutex_unlock(&system_transition_mutex);
993 pm_pr_dbg("Hibernation image not present or could not be loaded.\n");
994 return error;
995 Close_Finish:
996 swsusp_close();
997 goto Finish;
998}
999
1000/**
1001 * software_resume_initcall - Resume from a saved hibernation image.
1002 *
1003 * This routine is called as a late initcall, when all devices have been
1004 * discovered and initialized already.
1005 *
1006 * The image reading code is called to see if there is a hibernation image
1007 * available for reading. If that is the case, devices are quiesced and the
1008 * contents of memory is restored from the saved image.
1009 *
1010 * If this is successful, control reappears in the restored target kernel in
1011 * hibernation_snapshot() which returns to hibernate(). Otherwise, the routine
1012 * attempts to recover gracefully and make the kernel return to the normal mode
1013 * of operation.
1014 */
1015static int __init software_resume_initcall(void)
1016{
1017 /*
1018 * If the user said "noresume".. bail out early.
1019 */
1020 if (noresume || !hibernation_available())
1021 return 0;
1022
1023 if (!swsusp_resume_device) {
1024 int error = find_resume_device();
1025
1026 if (error)
1027 return error;
1028 }
1029
1030 return software_resume();
1031}
1032late_initcall_sync(software_resume_initcall);
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 dev;
1172 int error;
1173
1174 if (!hibernation_available())
1175 return n;
1176
1177 if (len && buf[len-1] == '\n')
1178 len--;
1179 name = kstrndup(buf, len, GFP_KERNEL);
1180 if (!name)
1181 return -ENOMEM;
1182
1183 error = lookup_bdev(name, &dev);
1184 if (error) {
1185 unsigned maj, min, offset;
1186 char *p, dummy;
1187
1188 error = 0;
1189 if (sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2 ||
1190 sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset,
1191 &dummy) == 3) {
1192 dev = MKDEV(maj, min);
1193 if (maj != MAJOR(dev) || min != MINOR(dev))
1194 error = -EINVAL;
1195 } else {
1196 dev = new_decode_dev(simple_strtoul(name, &p, 16));
1197 if (*p)
1198 error = -EINVAL;
1199 }
1200 }
1201 kfree(name);
1202 if (error)
1203 return error;
1204
1205 sleep_flags = lock_system_sleep();
1206 swsusp_resume_device = dev;
1207 unlock_system_sleep(sleep_flags);
1208
1209 pm_pr_dbg("Configured hibernation resume from disk to %u\n",
1210 swsusp_resume_device);
1211 noresume = 0;
1212 software_resume();
1213 return n;
1214}
1215
1216power_attr(resume);
1217
1218static ssize_t resume_offset_show(struct kobject *kobj,
1219 struct kobj_attribute *attr, char *buf)
1220{
1221 return sprintf(buf, "%llu\n", (unsigned long long)swsusp_resume_block);
1222}
1223
1224static ssize_t resume_offset_store(struct kobject *kobj,
1225 struct kobj_attribute *attr, const char *buf,
1226 size_t n)
1227{
1228 unsigned long long offset;
1229 int rc;
1230
1231 rc = kstrtoull(buf, 0, &offset);
1232 if (rc)
1233 return rc;
1234 swsusp_resume_block = offset;
1235
1236 return n;
1237}
1238
1239power_attr(resume_offset);
1240
1241static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
1242 char *buf)
1243{
1244 return sprintf(buf, "%lu\n", image_size);
1245}
1246
1247static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
1248 const char *buf, size_t n)
1249{
1250 unsigned long size;
1251
1252 if (sscanf(buf, "%lu", &size) == 1) {
1253 image_size = size;
1254 return n;
1255 }
1256
1257 return -EINVAL;
1258}
1259
1260power_attr(image_size);
1261
1262static ssize_t reserved_size_show(struct kobject *kobj,
1263 struct kobj_attribute *attr, char *buf)
1264{
1265 return sprintf(buf, "%lu\n", reserved_size);
1266}
1267
1268static ssize_t reserved_size_store(struct kobject *kobj,
1269 struct kobj_attribute *attr,
1270 const char *buf, size_t n)
1271{
1272 unsigned long size;
1273
1274 if (sscanf(buf, "%lu", &size) == 1) {
1275 reserved_size = size;
1276 return n;
1277 }
1278
1279 return -EINVAL;
1280}
1281
1282power_attr(reserved_size);
1283
1284static struct attribute *g[] = {
1285 &disk_attr.attr,
1286 &resume_offset_attr.attr,
1287 &resume_attr.attr,
1288 &image_size_attr.attr,
1289 &reserved_size_attr.attr,
1290 NULL,
1291};
1292
1293
1294static const struct attribute_group attr_group = {
1295 .attrs = g,
1296};
1297
1298
1299static int __init pm_disk_init(void)
1300{
1301 return sysfs_create_group(power_kobj, &attr_group);
1302}
1303
1304core_initcall(pm_disk_init);
1305
1306
1307static int __init resume_setup(char *str)
1308{
1309 if (noresume)
1310 return 1;
1311
1312 strncpy(resume_file, str, 255);
1313 return 1;
1314}
1315
1316static int __init resume_offset_setup(char *str)
1317{
1318 unsigned long long offset;
1319
1320 if (noresume)
1321 return 1;
1322
1323 if (sscanf(str, "%llu", &offset) == 1)
1324 swsusp_resume_block = offset;
1325
1326 return 1;
1327}
1328
1329static int __init hibernate_setup(char *str)
1330{
1331 if (!strncmp(str, "noresume", 8)) {
1332 noresume = 1;
1333 } else if (!strncmp(str, "nocompress", 10)) {
1334 nocompress = 1;
1335 } else if (!strncmp(str, "no", 2)) {
1336 noresume = 1;
1337 nohibernate = 1;
1338 } else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)
1339 && !strncmp(str, "protect_image", 13)) {
1340 enable_restore_image_protection();
1341 }
1342 return 1;
1343}
1344
1345static int __init noresume_setup(char *str)
1346{
1347 noresume = 1;
1348 return 1;
1349}
1350
1351static int __init resumewait_setup(char *str)
1352{
1353 resume_wait = 1;
1354 return 1;
1355}
1356
1357static int __init resumedelay_setup(char *str)
1358{
1359 int rc = kstrtouint(str, 0, &resume_delay);
1360
1361 if (rc)
1362 pr_warn("resumedelay: bad option string '%s'\n", str);
1363 return 1;
1364}
1365
1366static int __init nohibernate_setup(char *str)
1367{
1368 noresume = 1;
1369 nohibernate = 1;
1370 return 1;
1371}
1372
1373__setup("noresume", noresume_setup);
1374__setup("resume_offset=", resume_offset_setup);
1375__setup("resume=", resume_setup);
1376__setup("hibernate=", hibernate_setup);
1377__setup("resumewait", resumewait_setup);
1378__setup("resumedelay=", resumedelay_setup);
1379__setup("nohibernate", nohibernate_setup);