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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
50static char hibernate_compressor[CRYPTO_MAX_ALG_NAME] = CONFIG_HIBERNATION_DEF_COMP;
51
52/*
53 * Compression/decompression algorithm to be used while saving/loading
54 * image to/from disk. This would later be used in 'kernel/power/swap.c'
55 * to allocate comp streams.
56 */
57char hib_comp_algo[CRYPTO_MAX_ALG_NAME];
58
59enum {
60 HIBERNATION_INVALID,
61 HIBERNATION_PLATFORM,
62 HIBERNATION_SHUTDOWN,
63 HIBERNATION_REBOOT,
64#ifdef CONFIG_SUSPEND
65 HIBERNATION_SUSPEND,
66#endif
67 HIBERNATION_TEST_RESUME,
68 /* keep last */
69 __HIBERNATION_AFTER_LAST
70};
71#define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
72#define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
73
74static int hibernation_mode = HIBERNATION_SHUTDOWN;
75
76bool freezer_test_done;
77
78static const struct platform_hibernation_ops *hibernation_ops;
79
80static atomic_t hibernate_atomic = ATOMIC_INIT(1);
81
82bool hibernate_acquire(void)
83{
84 return atomic_add_unless(&hibernate_atomic, -1, 0);
85}
86
87void hibernate_release(void)
88{
89 atomic_inc(&hibernate_atomic);
90}
91
92bool hibernation_available(void)
93{
94 return nohibernate == 0 &&
95 !security_locked_down(LOCKDOWN_HIBERNATION) &&
96 !secretmem_active() && !cxl_mem_active();
97}
98
99/**
100 * hibernation_set_ops - Set the global hibernate operations.
101 * @ops: Hibernation operations to use in subsequent hibernation transitions.
102 */
103void hibernation_set_ops(const struct platform_hibernation_ops *ops)
104{
105 unsigned int sleep_flags;
106
107 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
108 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
109 && ops->restore_cleanup && ops->leave)) {
110 WARN_ON(1);
111 return;
112 }
113
114 sleep_flags = lock_system_sleep();
115
116 hibernation_ops = ops;
117 if (ops)
118 hibernation_mode = HIBERNATION_PLATFORM;
119 else if (hibernation_mode == HIBERNATION_PLATFORM)
120 hibernation_mode = HIBERNATION_SHUTDOWN;
121
122 unlock_system_sleep(sleep_flags);
123}
124EXPORT_SYMBOL_GPL(hibernation_set_ops);
125
126static bool entering_platform_hibernation;
127
128bool system_entering_hibernation(void)
129{
130 return entering_platform_hibernation;
131}
132EXPORT_SYMBOL(system_entering_hibernation);
133
134#ifdef CONFIG_PM_DEBUG
135static void hibernation_debug_sleep(void)
136{
137 pr_info("debug: Waiting for 5 seconds.\n");
138 mdelay(5000);
139}
140
141static int hibernation_test(int level)
142{
143 if (pm_test_level == level) {
144 hibernation_debug_sleep();
145 return 1;
146 }
147 return 0;
148}
149#else /* !CONFIG_PM_DEBUG */
150static int hibernation_test(int level) { return 0; }
151#endif /* !CONFIG_PM_DEBUG */
152
153/**
154 * platform_begin - Call platform to start hibernation.
155 * @platform_mode: Whether or not to use the platform driver.
156 */
157static int platform_begin(int platform_mode)
158{
159 return (platform_mode && hibernation_ops) ?
160 hibernation_ops->begin(PMSG_FREEZE) : 0;
161}
162
163/**
164 * platform_end - Call platform to finish transition to the working state.
165 * @platform_mode: Whether or not to use the platform driver.
166 */
167static void platform_end(int platform_mode)
168{
169 if (platform_mode && hibernation_ops)
170 hibernation_ops->end();
171}
172
173/**
174 * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
175 * @platform_mode: Whether or not to use the platform driver.
176 *
177 * Use the platform driver to prepare the system for creating a hibernate image,
178 * if so configured, and return an error code if that fails.
179 */
180
181static int platform_pre_snapshot(int platform_mode)
182{
183 return (platform_mode && hibernation_ops) ?
184 hibernation_ops->pre_snapshot() : 0;
185}
186
187/**
188 * platform_leave - Call platform to prepare a transition to the working state.
189 * @platform_mode: Whether or not to use the platform driver.
190 *
191 * Use the platform driver prepare to prepare the machine for switching to the
192 * normal mode of operation.
193 *
194 * This routine is called on one CPU with interrupts disabled.
195 */
196static void platform_leave(int platform_mode)
197{
198 if (platform_mode && hibernation_ops)
199 hibernation_ops->leave();
200}
201
202/**
203 * platform_finish - Call platform to switch the system to the working state.
204 * @platform_mode: Whether or not to use the platform driver.
205 *
206 * Use the platform driver to switch the machine to the normal mode of
207 * operation.
208 *
209 * This routine must be called after platform_prepare().
210 */
211static void platform_finish(int platform_mode)
212{
213 if (platform_mode && hibernation_ops)
214 hibernation_ops->finish();
215}
216
217/**
218 * platform_pre_restore - Prepare for hibernate image restoration.
219 * @platform_mode: Whether or not to use the platform driver.
220 *
221 * Use the platform driver to prepare the system for resume from a hibernation
222 * image.
223 *
224 * If the restore fails after this function has been called,
225 * platform_restore_cleanup() must be called.
226 */
227static int platform_pre_restore(int platform_mode)
228{
229 return (platform_mode && hibernation_ops) ?
230 hibernation_ops->pre_restore() : 0;
231}
232
233/**
234 * platform_restore_cleanup - Switch to the working state after failing restore.
235 * @platform_mode: Whether or not to use the platform driver.
236 *
237 * Use the platform driver to switch the system to the normal mode of operation
238 * after a failing restore.
239 *
240 * If platform_pre_restore() has been called before the failing restore, this
241 * function must be called too, regardless of the result of
242 * platform_pre_restore().
243 */
244static void platform_restore_cleanup(int platform_mode)
245{
246 if (platform_mode && hibernation_ops)
247 hibernation_ops->restore_cleanup();
248}
249
250/**
251 * platform_recover - Recover from a failure to suspend devices.
252 * @platform_mode: Whether or not to use the platform driver.
253 */
254static void platform_recover(int platform_mode)
255{
256 if (platform_mode && hibernation_ops && hibernation_ops->recover)
257 hibernation_ops->recover();
258}
259
260/**
261 * swsusp_show_speed - Print time elapsed between two events during hibernation.
262 * @start: Starting event.
263 * @stop: Final event.
264 * @nr_pages: Number of memory pages processed between @start and @stop.
265 * @msg: Additional diagnostic message to print.
266 */
267void swsusp_show_speed(ktime_t start, ktime_t stop,
268 unsigned nr_pages, char *msg)
269{
270 ktime_t diff;
271 u64 elapsed_centisecs64;
272 unsigned int centisecs;
273 unsigned int k;
274 unsigned int kps;
275
276 diff = ktime_sub(stop, start);
277 elapsed_centisecs64 = ktime_divns(diff, 10*NSEC_PER_MSEC);
278 centisecs = elapsed_centisecs64;
279 if (centisecs == 0)
280 centisecs = 1; /* avoid div-by-zero */
281 k = nr_pages * (PAGE_SIZE / 1024);
282 kps = (k * 100) / centisecs;
283 pr_info("%s %u kbytes in %u.%02u seconds (%u.%02u MB/s)\n",
284 msg, k, centisecs / 100, centisecs % 100, kps / 1000,
285 (kps % 1000) / 10);
286}
287
288__weak int arch_resume_nosmt(void)
289{
290 return 0;
291}
292
293/**
294 * create_image - Create a hibernation image.
295 * @platform_mode: Whether or not to use the platform driver.
296 *
297 * Execute device drivers' "late" and "noirq" freeze callbacks, create a
298 * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
299 *
300 * Control reappears in this routine after the subsequent restore.
301 */
302static int create_image(int platform_mode)
303{
304 int error;
305
306 error = dpm_suspend_end(PMSG_FREEZE);
307 if (error) {
308 pr_err("Some devices failed to power down, aborting\n");
309 return error;
310 }
311
312 error = platform_pre_snapshot(platform_mode);
313 if (error || hibernation_test(TEST_PLATFORM))
314 goto Platform_finish;
315
316 error = pm_sleep_disable_secondary_cpus();
317 if (error || hibernation_test(TEST_CPUS))
318 goto Enable_cpus;
319
320 local_irq_disable();
321
322 system_state = SYSTEM_SUSPEND;
323
324 error = syscore_suspend();
325 if (error) {
326 pr_err("Some system devices failed to power down, aborting\n");
327 goto Enable_irqs;
328 }
329
330 if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
331 goto Power_up;
332
333 in_suspend = 1;
334 save_processor_state();
335 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true);
336 error = swsusp_arch_suspend();
337 /* Restore control flow magically appears here */
338 restore_processor_state();
339 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false);
340 if (error)
341 pr_err("Error %d creating image\n", error);
342
343 if (!in_suspend) {
344 events_check_enabled = false;
345 clear_or_poison_free_pages();
346 }
347
348 platform_leave(platform_mode);
349
350 Power_up:
351 syscore_resume();
352
353 Enable_irqs:
354 system_state = SYSTEM_RUNNING;
355 local_irq_enable();
356
357 Enable_cpus:
358 pm_sleep_enable_secondary_cpus();
359
360 /* Allow architectures to do nosmt-specific post-resume dances */
361 if (!in_suspend)
362 error = arch_resume_nosmt();
363
364 Platform_finish:
365 platform_finish(platform_mode);
366
367 dpm_resume_start(in_suspend ?
368 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
369
370 return error;
371}
372
373/**
374 * hibernation_snapshot - Quiesce devices and create a hibernation image.
375 * @platform_mode: If set, use platform driver to prepare for the transition.
376 *
377 * This routine must be called with system_transition_mutex held.
378 */
379int hibernation_snapshot(int platform_mode)
380{
381 pm_message_t msg;
382 int error;
383
384 pm_suspend_clear_flags();
385 error = platform_begin(platform_mode);
386 if (error)
387 goto Close;
388
389 /* Preallocate image memory before shutting down devices. */
390 error = hibernate_preallocate_memory();
391 if (error)
392 goto Close;
393
394 error = freeze_kernel_threads();
395 if (error)
396 goto Cleanup;
397
398 if (hibernation_test(TEST_FREEZER)) {
399
400 /*
401 * Indicate to the caller that we are returning due to a
402 * successful freezer test.
403 */
404 freezer_test_done = true;
405 goto Thaw;
406 }
407
408 error = dpm_prepare(PMSG_FREEZE);
409 if (error) {
410 dpm_complete(PMSG_RECOVER);
411 goto Thaw;
412 }
413
414 suspend_console();
415 pm_restrict_gfp_mask();
416
417 error = dpm_suspend(PMSG_FREEZE);
418
419 if (error || hibernation_test(TEST_DEVICES))
420 platform_recover(platform_mode);
421 else
422 error = create_image(platform_mode);
423
424 /*
425 * In the case that we call create_image() above, the control
426 * returns here (1) after the image has been created or the
427 * image creation has failed and (2) after a successful restore.
428 */
429
430 /* We may need to release the preallocated image pages here. */
431 if (error || !in_suspend)
432 swsusp_free();
433
434 msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
435 dpm_resume(msg);
436
437 if (error || !in_suspend)
438 pm_restore_gfp_mask();
439
440 resume_console();
441 dpm_complete(msg);
442
443 Close:
444 platform_end(platform_mode);
445 return error;
446
447 Thaw:
448 thaw_kernel_threads();
449 Cleanup:
450 swsusp_free();
451 goto Close;
452}
453
454int __weak hibernate_resume_nonboot_cpu_disable(void)
455{
456 return suspend_disable_secondary_cpus();
457}
458
459/**
460 * resume_target_kernel - Restore system state from a hibernation image.
461 * @platform_mode: Whether or not to use the platform driver.
462 *
463 * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
464 * contents of highmem that have not been restored yet from the image and run
465 * the low-level code that will restore the remaining contents of memory and
466 * switch to the just restored target kernel.
467 */
468static int resume_target_kernel(bool platform_mode)
469{
470 int error;
471
472 error = dpm_suspend_end(PMSG_QUIESCE);
473 if (error) {
474 pr_err("Some devices failed to power down, aborting resume\n");
475 return error;
476 }
477
478 error = platform_pre_restore(platform_mode);
479 if (error)
480 goto Cleanup;
481
482 cpuidle_pause();
483
484 error = hibernate_resume_nonboot_cpu_disable();
485 if (error)
486 goto Enable_cpus;
487
488 local_irq_disable();
489 system_state = SYSTEM_SUSPEND;
490
491 error = syscore_suspend();
492 if (error)
493 goto Enable_irqs;
494
495 save_processor_state();
496 error = restore_highmem();
497 if (!error) {
498 error = swsusp_arch_resume();
499 /*
500 * The code below is only ever reached in case of a failure.
501 * Otherwise, execution continues at the place where
502 * swsusp_arch_suspend() was called.
503 */
504 BUG_ON(!error);
505 /*
506 * This call to restore_highmem() reverts the changes made by
507 * the previous one.
508 */
509 restore_highmem();
510 }
511 /*
512 * The only reason why swsusp_arch_resume() can fail is memory being
513 * very tight, so we have to free it as soon as we can to avoid
514 * subsequent failures.
515 */
516 swsusp_free();
517 restore_processor_state();
518 touch_softlockup_watchdog();
519
520 syscore_resume();
521
522 Enable_irqs:
523 system_state = SYSTEM_RUNNING;
524 local_irq_enable();
525
526 Enable_cpus:
527 pm_sleep_enable_secondary_cpus();
528
529 Cleanup:
530 platform_restore_cleanup(platform_mode);
531
532 dpm_resume_start(PMSG_RECOVER);
533
534 return error;
535}
536
537/**
538 * hibernation_restore - Quiesce devices and restore from a hibernation image.
539 * @platform_mode: If set, use platform driver to prepare for the transition.
540 *
541 * This routine must be called with system_transition_mutex held. If it is
542 * successful, control reappears in the restored target kernel in
543 * hibernation_snapshot().
544 */
545int hibernation_restore(int platform_mode)
546{
547 int error;
548
549 pm_prepare_console();
550 suspend_console();
551 pm_restrict_gfp_mask();
552 error = dpm_suspend_start(PMSG_QUIESCE);
553 if (!error) {
554 error = resume_target_kernel(platform_mode);
555 /*
556 * The above should either succeed and jump to the new kernel,
557 * or return with an error. Otherwise things are just
558 * undefined, so let's be paranoid.
559 */
560 BUG_ON(!error);
561 }
562 dpm_resume_end(PMSG_RECOVER);
563 pm_restore_gfp_mask();
564 resume_console();
565 pm_restore_console();
566 return error;
567}
568
569/**
570 * hibernation_platform_enter - Power off the system using the platform driver.
571 */
572int hibernation_platform_enter(void)
573{
574 int error;
575
576 if (!hibernation_ops)
577 return -ENOSYS;
578
579 /*
580 * We have cancelled the power transition by running
581 * hibernation_ops->finish() before saving the image, so we should let
582 * the firmware know that we're going to enter the sleep state after all
583 */
584 error = hibernation_ops->begin(PMSG_HIBERNATE);
585 if (error)
586 goto Close;
587
588 entering_platform_hibernation = true;
589 suspend_console();
590 error = dpm_suspend_start(PMSG_HIBERNATE);
591 if (error) {
592 if (hibernation_ops->recover)
593 hibernation_ops->recover();
594 goto Resume_devices;
595 }
596
597 error = dpm_suspend_end(PMSG_HIBERNATE);
598 if (error)
599 goto Resume_devices;
600
601 error = hibernation_ops->prepare();
602 if (error)
603 goto Platform_finish;
604
605 error = pm_sleep_disable_secondary_cpus();
606 if (error)
607 goto Enable_cpus;
608
609 local_irq_disable();
610 system_state = SYSTEM_SUSPEND;
611
612 error = syscore_suspend();
613 if (error)
614 goto Enable_irqs;
615
616 if (pm_wakeup_pending()) {
617 error = -EAGAIN;
618 goto Power_up;
619 }
620
621 hibernation_ops->enter();
622 /* We should never get here */
623 while (1);
624
625 Power_up:
626 syscore_resume();
627 Enable_irqs:
628 system_state = SYSTEM_RUNNING;
629 local_irq_enable();
630
631 Enable_cpus:
632 pm_sleep_enable_secondary_cpus();
633
634 Platform_finish:
635 hibernation_ops->finish();
636
637 dpm_resume_start(PMSG_RESTORE);
638
639 Resume_devices:
640 entering_platform_hibernation = false;
641 dpm_resume_end(PMSG_RESTORE);
642 resume_console();
643
644 Close:
645 hibernation_ops->end();
646
647 return error;
648}
649
650/**
651 * power_down - Shut the machine down for hibernation.
652 *
653 * Use the platform driver, if configured, to put the system into the sleep
654 * state corresponding to hibernation, or try to power it off or reboot,
655 * depending on the value of hibernation_mode.
656 */
657static void power_down(void)
658{
659 int error;
660
661#ifdef CONFIG_SUSPEND
662 if (hibernation_mode == HIBERNATION_SUSPEND) {
663 error = suspend_devices_and_enter(mem_sleep_current);
664 if (error) {
665 hibernation_mode = hibernation_ops ?
666 HIBERNATION_PLATFORM :
667 HIBERNATION_SHUTDOWN;
668 } else {
669 /* Restore swap signature. */
670 error = swsusp_unmark();
671 if (error)
672 pr_err("Swap will be unusable! Try swapon -a.\n");
673
674 return;
675 }
676 }
677#endif
678
679 switch (hibernation_mode) {
680 case HIBERNATION_REBOOT:
681 kernel_restart(NULL);
682 break;
683 case HIBERNATION_PLATFORM:
684 error = hibernation_platform_enter();
685 if (error == -EAGAIN || error == -EBUSY) {
686 swsusp_unmark();
687 events_check_enabled = false;
688 pr_info("Wakeup event detected during hibernation, rolling back.\n");
689 return;
690 }
691 fallthrough;
692 case HIBERNATION_SHUTDOWN:
693 if (kernel_can_power_off()) {
694 entering_platform_hibernation = true;
695 kernel_power_off();
696 entering_platform_hibernation = false;
697 }
698 break;
699 }
700 kernel_halt();
701 /*
702 * Valid image is on the disk, if we continue we risk serious data
703 * corruption after resume.
704 */
705 pr_crit("Power down manually\n");
706 while (1)
707 cpu_relax();
708}
709
710static int load_image_and_restore(void)
711{
712 int error;
713 unsigned int flags;
714
715 pm_pr_dbg("Loading hibernation image.\n");
716
717 lock_device_hotplug();
718 error = create_basic_memory_bitmaps();
719 if (error) {
720 swsusp_close();
721 goto Unlock;
722 }
723
724 error = swsusp_read(&flags);
725 swsusp_close();
726 if (!error)
727 error = hibernation_restore(flags & SF_PLATFORM_MODE);
728
729 pr_err("Failed to load image, recovering.\n");
730 swsusp_free();
731 free_basic_memory_bitmaps();
732 Unlock:
733 unlock_device_hotplug();
734
735 return error;
736}
737
738#define COMPRESSION_ALGO_LZO "lzo"
739#define COMPRESSION_ALGO_LZ4 "lz4"
740
741/**
742 * hibernate - Carry out system hibernation, including saving the image.
743 */
744int hibernate(void)
745{
746 bool snapshot_test = false;
747 unsigned int sleep_flags;
748 int error;
749
750 if (!hibernation_available()) {
751 pm_pr_dbg("Hibernation not available.\n");
752 return -EPERM;
753 }
754
755 /*
756 * Query for the compression algorithm support if compression is enabled.
757 */
758 if (!nocompress) {
759 strscpy(hib_comp_algo, hibernate_compressor, sizeof(hib_comp_algo));
760 if (crypto_has_comp(hib_comp_algo, 0, 0) != 1) {
761 pr_err("%s compression is not available\n", hib_comp_algo);
762 return -EOPNOTSUPP;
763 }
764 }
765
766 sleep_flags = lock_system_sleep();
767 /* The snapshot device should not be opened while we're running */
768 if (!hibernate_acquire()) {
769 error = -EBUSY;
770 goto Unlock;
771 }
772
773 pr_info("hibernation entry\n");
774 pm_prepare_console();
775 error = pm_notifier_call_chain_robust(PM_HIBERNATION_PREPARE, PM_POST_HIBERNATION);
776 if (error)
777 goto Restore;
778
779 ksys_sync_helper();
780
781 error = freeze_processes();
782 if (error)
783 goto Exit;
784
785 lock_device_hotplug();
786 /* Allocate memory management structures */
787 error = create_basic_memory_bitmaps();
788 if (error)
789 goto Thaw;
790
791 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
792 if (error || freezer_test_done)
793 goto Free_bitmaps;
794
795 if (in_suspend) {
796 unsigned int flags = 0;
797
798 if (hibernation_mode == HIBERNATION_PLATFORM)
799 flags |= SF_PLATFORM_MODE;
800 if (nocompress) {
801 flags |= SF_NOCOMPRESS_MODE;
802 } else {
803 flags |= SF_CRC32_MODE;
804
805 /*
806 * By default, LZO compression is enabled. Use SF_COMPRESSION_ALG_LZ4
807 * to override this behaviour and use LZ4.
808 *
809 * Refer kernel/power/power.h for more details
810 */
811
812 if (!strcmp(hib_comp_algo, COMPRESSION_ALGO_LZ4))
813 flags |= SF_COMPRESSION_ALG_LZ4;
814 else
815 flags |= SF_COMPRESSION_ALG_LZO;
816 }
817
818 pm_pr_dbg("Writing hibernation image.\n");
819 error = swsusp_write(flags);
820 swsusp_free();
821 if (!error) {
822 if (hibernation_mode == HIBERNATION_TEST_RESUME)
823 snapshot_test = true;
824 else
825 power_down();
826 }
827 in_suspend = 0;
828 pm_restore_gfp_mask();
829 } else {
830 pm_pr_dbg("Hibernation image restored successfully.\n");
831 }
832
833 Free_bitmaps:
834 free_basic_memory_bitmaps();
835 Thaw:
836 unlock_device_hotplug();
837 if (snapshot_test) {
838 pm_pr_dbg("Checking hibernation image\n");
839 error = swsusp_check(false);
840 if (!error)
841 error = load_image_and_restore();
842 }
843 thaw_processes();
844
845 /* Don't bother checking whether freezer_test_done is true */
846 freezer_test_done = false;
847 Exit:
848 pm_notifier_call_chain(PM_POST_HIBERNATION);
849 Restore:
850 pm_restore_console();
851 hibernate_release();
852 Unlock:
853 unlock_system_sleep(sleep_flags);
854 pr_info("hibernation exit\n");
855
856 return error;
857}
858
859/**
860 * hibernate_quiet_exec - Execute a function with all devices frozen.
861 * @func: Function to execute.
862 * @data: Data pointer to pass to @func.
863 *
864 * Return the @func return value or an error code if it cannot be executed.
865 */
866int hibernate_quiet_exec(int (*func)(void *data), void *data)
867{
868 unsigned int sleep_flags;
869 int error;
870
871 sleep_flags = lock_system_sleep();
872
873 if (!hibernate_acquire()) {
874 error = -EBUSY;
875 goto unlock;
876 }
877
878 pm_prepare_console();
879
880 error = pm_notifier_call_chain_robust(PM_HIBERNATION_PREPARE, PM_POST_HIBERNATION);
881 if (error)
882 goto restore;
883
884 error = freeze_processes();
885 if (error)
886 goto exit;
887
888 lock_device_hotplug();
889
890 pm_suspend_clear_flags();
891
892 error = platform_begin(true);
893 if (error)
894 goto thaw;
895
896 error = freeze_kernel_threads();
897 if (error)
898 goto thaw;
899
900 error = dpm_prepare(PMSG_FREEZE);
901 if (error)
902 goto dpm_complete;
903
904 suspend_console();
905
906 error = dpm_suspend(PMSG_FREEZE);
907 if (error)
908 goto dpm_resume;
909
910 error = dpm_suspend_end(PMSG_FREEZE);
911 if (error)
912 goto dpm_resume;
913
914 error = platform_pre_snapshot(true);
915 if (error)
916 goto skip;
917
918 error = func(data);
919
920skip:
921 platform_finish(true);
922
923 dpm_resume_start(PMSG_THAW);
924
925dpm_resume:
926 dpm_resume(PMSG_THAW);
927
928 resume_console();
929
930dpm_complete:
931 dpm_complete(PMSG_THAW);
932
933 thaw_kernel_threads();
934
935thaw:
936 platform_end(true);
937
938 unlock_device_hotplug();
939
940 thaw_processes();
941
942exit:
943 pm_notifier_call_chain(PM_POST_HIBERNATION);
944
945restore:
946 pm_restore_console();
947
948 hibernate_release();
949
950unlock:
951 unlock_system_sleep(sleep_flags);
952
953 return error;
954}
955EXPORT_SYMBOL_GPL(hibernate_quiet_exec);
956
957static int __init find_resume_device(void)
958{
959 if (!strlen(resume_file))
960 return -ENOENT;
961
962 pm_pr_dbg("Checking hibernation image partition %s\n", resume_file);
963
964 if (resume_delay) {
965 pr_info("Waiting %dsec before reading resume device ...\n",
966 resume_delay);
967 ssleep(resume_delay);
968 }
969
970 /* Check if the device is there */
971 if (!early_lookup_bdev(resume_file, &swsusp_resume_device))
972 return 0;
973
974 /*
975 * Some device discovery might still be in progress; we need to wait for
976 * this to finish.
977 */
978 wait_for_device_probe();
979 if (resume_wait) {
980 while (early_lookup_bdev(resume_file, &swsusp_resume_device))
981 msleep(10);
982 async_synchronize_full();
983 }
984
985 return early_lookup_bdev(resume_file, &swsusp_resume_device);
986}
987
988static int software_resume(void)
989{
990 int error;
991
992 pm_pr_dbg("Hibernation image partition %d:%d present\n",
993 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
994
995 pm_pr_dbg("Looking for hibernation image.\n");
996
997 mutex_lock(&system_transition_mutex);
998 error = swsusp_check(true);
999 if (error)
1000 goto Unlock;
1001
1002 /*
1003 * Check if the hibernation image is compressed. If so, query for
1004 * the algorithm support.
1005 */
1006 if (!(swsusp_header_flags & SF_NOCOMPRESS_MODE)) {
1007 if (swsusp_header_flags & SF_COMPRESSION_ALG_LZ4)
1008 strscpy(hib_comp_algo, COMPRESSION_ALGO_LZ4, sizeof(hib_comp_algo));
1009 else
1010 strscpy(hib_comp_algo, COMPRESSION_ALGO_LZO, sizeof(hib_comp_algo));
1011 if (crypto_has_comp(hib_comp_algo, 0, 0) != 1) {
1012 pr_err("%s compression is not available\n", hib_comp_algo);
1013 error = -EOPNOTSUPP;
1014 goto Unlock;
1015 }
1016 }
1017
1018 /* The snapshot device should not be opened while we're running */
1019 if (!hibernate_acquire()) {
1020 error = -EBUSY;
1021 swsusp_close();
1022 goto Unlock;
1023 }
1024
1025 pr_info("resume from hibernation\n");
1026 pm_prepare_console();
1027 error = pm_notifier_call_chain_robust(PM_RESTORE_PREPARE, PM_POST_RESTORE);
1028 if (error)
1029 goto Restore;
1030
1031 pm_pr_dbg("Preparing processes for hibernation restore.\n");
1032 error = freeze_processes();
1033 if (error)
1034 goto Close_Finish;
1035
1036 error = freeze_kernel_threads();
1037 if (error) {
1038 thaw_processes();
1039 goto Close_Finish;
1040 }
1041
1042 error = load_image_and_restore();
1043 thaw_processes();
1044 Finish:
1045 pm_notifier_call_chain(PM_POST_RESTORE);
1046 Restore:
1047 pm_restore_console();
1048 pr_info("resume failed (%d)\n", error);
1049 hibernate_release();
1050 /* For success case, the suspend path will release the lock */
1051 Unlock:
1052 mutex_unlock(&system_transition_mutex);
1053 pm_pr_dbg("Hibernation image not present or could not be loaded.\n");
1054 return error;
1055 Close_Finish:
1056 swsusp_close();
1057 goto Finish;
1058}
1059
1060/**
1061 * software_resume_initcall - Resume from a saved hibernation image.
1062 *
1063 * This routine is called as a late initcall, when all devices have been
1064 * discovered and initialized already.
1065 *
1066 * The image reading code is called to see if there is a hibernation image
1067 * available for reading. If that is the case, devices are quiesced and the
1068 * contents of memory is restored from the saved image.
1069 *
1070 * If this is successful, control reappears in the restored target kernel in
1071 * hibernation_snapshot() which returns to hibernate(). Otherwise, the routine
1072 * attempts to recover gracefully and make the kernel return to the normal mode
1073 * of operation.
1074 */
1075static int __init software_resume_initcall(void)
1076{
1077 /*
1078 * If the user said "noresume".. bail out early.
1079 */
1080 if (noresume || !hibernation_available())
1081 return 0;
1082
1083 if (!swsusp_resume_device) {
1084 int error = find_resume_device();
1085
1086 if (error)
1087 return error;
1088 }
1089
1090 return software_resume();
1091}
1092late_initcall_sync(software_resume_initcall);
1093
1094
1095static const char * const hibernation_modes[] = {
1096 [HIBERNATION_PLATFORM] = "platform",
1097 [HIBERNATION_SHUTDOWN] = "shutdown",
1098 [HIBERNATION_REBOOT] = "reboot",
1099#ifdef CONFIG_SUSPEND
1100 [HIBERNATION_SUSPEND] = "suspend",
1101#endif
1102 [HIBERNATION_TEST_RESUME] = "test_resume",
1103};
1104
1105/*
1106 * /sys/power/disk - Control hibernation mode.
1107 *
1108 * Hibernation can be handled in several ways. There are a few different ways
1109 * to put the system into the sleep state: using the platform driver (e.g. ACPI
1110 * or other hibernation_ops), powering it off or rebooting it (for testing
1111 * mostly).
1112 *
1113 * The sysfs file /sys/power/disk provides an interface for selecting the
1114 * hibernation mode to use. Reading from this file causes the available modes
1115 * to be printed. There are 3 modes that can be supported:
1116 *
1117 * 'platform'
1118 * 'shutdown'
1119 * 'reboot'
1120 *
1121 * If a platform hibernation driver is in use, 'platform' will be supported
1122 * and will be used by default. Otherwise, 'shutdown' will be used by default.
1123 * The selected option (i.e. the one corresponding to the current value of
1124 * hibernation_mode) is enclosed by a square bracket.
1125 *
1126 * To select a given hibernation mode it is necessary to write the mode's
1127 * string representation (as returned by reading from /sys/power/disk) back
1128 * into /sys/power/disk.
1129 */
1130
1131static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
1132 char *buf)
1133{
1134 ssize_t count = 0;
1135 int i;
1136
1137 if (!hibernation_available())
1138 return sysfs_emit(buf, "[disabled]\n");
1139
1140 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
1141 if (!hibernation_modes[i])
1142 continue;
1143 switch (i) {
1144 case HIBERNATION_SHUTDOWN:
1145 case HIBERNATION_REBOOT:
1146#ifdef CONFIG_SUSPEND
1147 case HIBERNATION_SUSPEND:
1148#endif
1149 case HIBERNATION_TEST_RESUME:
1150 break;
1151 case HIBERNATION_PLATFORM:
1152 if (hibernation_ops)
1153 break;
1154 /* not a valid mode, continue with loop */
1155 continue;
1156 }
1157 if (i == hibernation_mode)
1158 count += sysfs_emit_at(buf, count, "[%s] ", hibernation_modes[i]);
1159 else
1160 count += sysfs_emit_at(buf, count, "%s ", hibernation_modes[i]);
1161 }
1162
1163 /* Convert the last space to a newline if needed. */
1164 if (count > 0)
1165 buf[count - 1] = '\n';
1166
1167 return count;
1168}
1169
1170static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
1171 const char *buf, size_t n)
1172{
1173 int mode = HIBERNATION_INVALID;
1174 unsigned int sleep_flags;
1175 int error = 0;
1176 int len;
1177 char *p;
1178 int i;
1179
1180 if (!hibernation_available())
1181 return -EPERM;
1182
1183 p = memchr(buf, '\n', n);
1184 len = p ? p - buf : n;
1185
1186 sleep_flags = lock_system_sleep();
1187 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
1188 if (len == strlen(hibernation_modes[i])
1189 && !strncmp(buf, hibernation_modes[i], len)) {
1190 mode = i;
1191 break;
1192 }
1193 }
1194 if (mode != HIBERNATION_INVALID) {
1195 switch (mode) {
1196 case HIBERNATION_SHUTDOWN:
1197 case HIBERNATION_REBOOT:
1198#ifdef CONFIG_SUSPEND
1199 case HIBERNATION_SUSPEND:
1200#endif
1201 case HIBERNATION_TEST_RESUME:
1202 hibernation_mode = mode;
1203 break;
1204 case HIBERNATION_PLATFORM:
1205 if (hibernation_ops)
1206 hibernation_mode = mode;
1207 else
1208 error = -EINVAL;
1209 }
1210 } else
1211 error = -EINVAL;
1212
1213 if (!error)
1214 pm_pr_dbg("Hibernation mode set to '%s'\n",
1215 hibernation_modes[mode]);
1216 unlock_system_sleep(sleep_flags);
1217 return error ? error : n;
1218}
1219
1220power_attr(disk);
1221
1222static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
1223 char *buf)
1224{
1225 return sysfs_emit(buf, "%d:%d\n", MAJOR(swsusp_resume_device),
1226 MINOR(swsusp_resume_device));
1227}
1228
1229static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
1230 const char *buf, size_t n)
1231{
1232 unsigned int sleep_flags;
1233 int len = n;
1234 char *name;
1235 dev_t dev;
1236 int error;
1237
1238 if (!hibernation_available())
1239 return n;
1240
1241 if (len && buf[len-1] == '\n')
1242 len--;
1243 name = kstrndup(buf, len, GFP_KERNEL);
1244 if (!name)
1245 return -ENOMEM;
1246
1247 error = lookup_bdev(name, &dev);
1248 if (error) {
1249 unsigned maj, min, offset;
1250 char *p, dummy;
1251
1252 error = 0;
1253 if (sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2 ||
1254 sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset,
1255 &dummy) == 3) {
1256 dev = MKDEV(maj, min);
1257 if (maj != MAJOR(dev) || min != MINOR(dev))
1258 error = -EINVAL;
1259 } else {
1260 dev = new_decode_dev(simple_strtoul(name, &p, 16));
1261 if (*p)
1262 error = -EINVAL;
1263 }
1264 }
1265 kfree(name);
1266 if (error)
1267 return error;
1268
1269 sleep_flags = lock_system_sleep();
1270 swsusp_resume_device = dev;
1271 unlock_system_sleep(sleep_flags);
1272
1273 pm_pr_dbg("Configured hibernation resume from disk to %u\n",
1274 swsusp_resume_device);
1275 noresume = 0;
1276 software_resume();
1277 return n;
1278}
1279
1280power_attr(resume);
1281
1282static ssize_t resume_offset_show(struct kobject *kobj,
1283 struct kobj_attribute *attr, char *buf)
1284{
1285 return sysfs_emit(buf, "%llu\n", (unsigned long long)swsusp_resume_block);
1286}
1287
1288static ssize_t resume_offset_store(struct kobject *kobj,
1289 struct kobj_attribute *attr, const char *buf,
1290 size_t n)
1291{
1292 unsigned long long offset;
1293 int rc;
1294
1295 rc = kstrtoull(buf, 0, &offset);
1296 if (rc)
1297 return rc;
1298 swsusp_resume_block = offset;
1299
1300 return n;
1301}
1302
1303power_attr(resume_offset);
1304
1305static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
1306 char *buf)
1307{
1308 return sysfs_emit(buf, "%lu\n", image_size);
1309}
1310
1311static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
1312 const char *buf, size_t n)
1313{
1314 unsigned long size;
1315
1316 if (sscanf(buf, "%lu", &size) == 1) {
1317 image_size = size;
1318 return n;
1319 }
1320
1321 return -EINVAL;
1322}
1323
1324power_attr(image_size);
1325
1326static ssize_t reserved_size_show(struct kobject *kobj,
1327 struct kobj_attribute *attr, char *buf)
1328{
1329 return sysfs_emit(buf, "%lu\n", reserved_size);
1330}
1331
1332static ssize_t reserved_size_store(struct kobject *kobj,
1333 struct kobj_attribute *attr,
1334 const char *buf, size_t n)
1335{
1336 unsigned long size;
1337
1338 if (sscanf(buf, "%lu", &size) == 1) {
1339 reserved_size = size;
1340 return n;
1341 }
1342
1343 return -EINVAL;
1344}
1345
1346power_attr(reserved_size);
1347
1348static struct attribute *g[] = {
1349 &disk_attr.attr,
1350 &resume_offset_attr.attr,
1351 &resume_attr.attr,
1352 &image_size_attr.attr,
1353 &reserved_size_attr.attr,
1354 NULL,
1355};
1356
1357
1358static const struct attribute_group attr_group = {
1359 .attrs = g,
1360};
1361
1362
1363static int __init pm_disk_init(void)
1364{
1365 return sysfs_create_group(power_kobj, &attr_group);
1366}
1367
1368core_initcall(pm_disk_init);
1369
1370
1371static int __init resume_setup(char *str)
1372{
1373 if (noresume)
1374 return 1;
1375
1376 strscpy(resume_file, str);
1377 return 1;
1378}
1379
1380static int __init resume_offset_setup(char *str)
1381{
1382 unsigned long long offset;
1383
1384 if (noresume)
1385 return 1;
1386
1387 if (sscanf(str, "%llu", &offset) == 1)
1388 swsusp_resume_block = offset;
1389
1390 return 1;
1391}
1392
1393static int __init hibernate_setup(char *str)
1394{
1395 if (!strncmp(str, "noresume", 8)) {
1396 noresume = 1;
1397 } else if (!strncmp(str, "nocompress", 10)) {
1398 nocompress = 1;
1399 } else if (!strncmp(str, "no", 2)) {
1400 noresume = 1;
1401 nohibernate = 1;
1402 } else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)
1403 && !strncmp(str, "protect_image", 13)) {
1404 enable_restore_image_protection();
1405 }
1406 return 1;
1407}
1408
1409static int __init noresume_setup(char *str)
1410{
1411 noresume = 1;
1412 return 1;
1413}
1414
1415static int __init resumewait_setup(char *str)
1416{
1417 resume_wait = 1;
1418 return 1;
1419}
1420
1421static int __init resumedelay_setup(char *str)
1422{
1423 int rc = kstrtouint(str, 0, &resume_delay);
1424
1425 if (rc)
1426 pr_warn("resumedelay: bad option string '%s'\n", str);
1427 return 1;
1428}
1429
1430static int __init nohibernate_setup(char *str)
1431{
1432 noresume = 1;
1433 nohibernate = 1;
1434 return 1;
1435}
1436
1437static const char * const comp_alg_enabled[] = {
1438#if IS_ENABLED(CONFIG_CRYPTO_LZO)
1439 COMPRESSION_ALGO_LZO,
1440#endif
1441#if IS_ENABLED(CONFIG_CRYPTO_LZ4)
1442 COMPRESSION_ALGO_LZ4,
1443#endif
1444};
1445
1446static int hibernate_compressor_param_set(const char *compressor,
1447 const struct kernel_param *kp)
1448{
1449 unsigned int sleep_flags;
1450 int index, ret;
1451
1452 sleep_flags = lock_system_sleep();
1453
1454 index = sysfs_match_string(comp_alg_enabled, compressor);
1455 if (index >= 0) {
1456 ret = param_set_copystring(comp_alg_enabled[index], kp);
1457 if (!ret)
1458 strscpy(hib_comp_algo, comp_alg_enabled[index],
1459 sizeof(hib_comp_algo));
1460 } else {
1461 ret = index;
1462 }
1463
1464 unlock_system_sleep(sleep_flags);
1465
1466 if (ret)
1467 pr_debug("Cannot set specified compressor %s\n",
1468 compressor);
1469
1470 return ret;
1471}
1472
1473static const struct kernel_param_ops hibernate_compressor_param_ops = {
1474 .set = hibernate_compressor_param_set,
1475 .get = param_get_string,
1476};
1477
1478static struct kparam_string hibernate_compressor_param_string = {
1479 .maxlen = sizeof(hibernate_compressor),
1480 .string = hibernate_compressor,
1481};
1482
1483module_param_cb(compressor, &hibernate_compressor_param_ops,
1484 &hibernate_compressor_param_string, 0644);
1485MODULE_PARM_DESC(compressor,
1486 "Compression algorithm to be used with hibernation");
1487
1488__setup("noresume", noresume_setup);
1489__setup("resume_offset=", resume_offset_setup);
1490__setup("resume=", resume_setup);
1491__setup("hibernate=", hibernate_setup);
1492__setup("resumewait", resumewait_setup);
1493__setup("resumedelay=", resumedelay_setup);
1494__setup("nohibernate", nohibernate_setup);