projects/linux·blob master · refs

1532 lines · 34.6 KiB

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 <[email protected]>
8 * Copyright (c) 2009 Rafael J. Wysocki, Novell Inc.
9 * Copyright (C) 2012 Bojan Smojver <[email protected]>
10 */
11
12#define pr_fmt(fmt) "PM: hibernation: " fmt
13
14#include <crypto/acompress.h>
15#include <linux/blkdev.h>
16#include <linux/export.h>
17#include <linux/suspend.h>
18#include <linux/reboot.h>
19#include <linux/string.h>
20#include <linux/device.h>
21#include <linux/async.h>
22#include <linux/delay.h>
23#include <linux/fs.h>
24#include <linux/mount.h>
25#include <linux/pm.h>
26#include <linux/nmi.h>
27#include <linux/console.h>
28#include <linux/cpu.h>
29#include <linux/freezer.h>
30#include <linux/gfp.h>
31#include <linux/syscore_ops.h>
32#include <linux/ctype.h>
33#include <linux/ktime.h>
34#include <linux/security.h>
35#include <linux/secretmem.h>
36#include <trace/events/power.h>
37
38#include "power.h"
39
40
41static int nocompress;
42static int noresume;
43static int nohibernate;
44static int resume_wait;
45static unsigned int resume_delay;
46static char resume_file[256] = CONFIG_PM_STD_PARTITION;
47dev_t swsusp_resume_device;
48sector_t swsusp_resume_block;
49__visible int in_suspend __nosavedata;
50
51static char hibernate_compressor[CRYPTO_MAX_ALG_NAME] = CONFIG_HIBERNATION_DEF_COMP;
52
53/*
54 * Compression/decompression algorithm to be used while saving/loading
55 * image to/from disk. This would later be used in 'kernel/power/swap.c'
56 * to allocate comp streams.
57 */
58char hib_comp_algo[CRYPTO_MAX_ALG_NAME];
59
60enum {
61 HIBERNATION_INVALID,
62 HIBERNATION_PLATFORM,
63 HIBERNATION_SHUTDOWN,
64 HIBERNATION_REBOOT,
65#ifdef CONFIG_SUSPEND
66 HIBERNATION_SUSPEND,
67#endif
68 HIBERNATION_TEST_RESUME,
69 /* keep last */
70 __HIBERNATION_AFTER_LAST
71};
72#define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
73#define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
74
75static int hibernation_mode = HIBERNATION_SHUTDOWN;
76
77bool freezer_test_done;
78
79static const struct platform_hibernation_ops *hibernation_ops;
80
81static atomic_t hibernate_atomic = ATOMIC_INIT(1);
82
83#ifdef CONFIG_SUSPEND
84/**
85 * pm_hibernation_mode_is_suspend - Check if hibernation has been set to suspend
86 */
87bool pm_hibernation_mode_is_suspend(void)
88{
89 return hibernation_mode == HIBERNATION_SUSPEND;
90}
91EXPORT_SYMBOL_GPL(pm_hibernation_mode_is_suspend);
92#endif
93
94bool hibernate_acquire(void)
95{
96 return atomic_add_unless(&hibernate_atomic, -1, 0);
97}
98
99void hibernate_release(void)
100{
101 atomic_inc(&hibernate_atomic);
102}
103
104bool hibernation_in_progress(void)
105{
106 return !atomic_read(&hibernate_atomic);
107}
108
109__weak bool arch_hibernation_available(void)
110{
111 return true;
112}
113
114bool hibernation_available(void)
115{
116 return nohibernate == 0 &&
117 !security_locked_down(LOCKDOWN_HIBERNATION) &&
118 !secretmem_active() && !cxl_mem_active() &&
119 arch_hibernation_available();
120}
121
122/**
123 * hibernation_set_ops - Set the global hibernate operations.
124 * @ops: Hibernation operations to use in subsequent hibernation transitions.
125 */
126void hibernation_set_ops(const struct platform_hibernation_ops *ops)
127{
128 unsigned int sleep_flags;
129
130 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
131 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
132 && ops->restore_cleanup && ops->leave)) {
133 WARN_ON(1);
134 return;
135 }
136
137 sleep_flags = lock_system_sleep();
138
139 hibernation_ops = ops;
140 if (ops)
141 hibernation_mode = HIBERNATION_PLATFORM;
142 else if (hibernation_mode == HIBERNATION_PLATFORM)
143 hibernation_mode = HIBERNATION_SHUTDOWN;
144
145 unlock_system_sleep(sleep_flags);
146}
147EXPORT_SYMBOL_GPL(hibernation_set_ops);
148
149static bool entering_platform_hibernation;
150
151bool system_entering_hibernation(void)
152{
153 return entering_platform_hibernation;
154}
155EXPORT_SYMBOL(system_entering_hibernation);
156
157#ifdef CONFIG_PM_DEBUG
158static unsigned int pm_test_delay = 5;
159module_param(pm_test_delay, uint, 0644);
160MODULE_PARM_DESC(pm_test_delay,
161 "Number of seconds to wait before resuming from hibernation test");
162static void hibernation_debug_sleep(void)
163{
164 pr_info("hibernation debug: Waiting for %d second(s).\n",
165 pm_test_delay);
166 mdelay(pm_test_delay * 1000);
167}
168
169static int hibernation_test(int level)
170{
171 if (pm_test_level == level) {
172 hibernation_debug_sleep();
173 return 1;
174 }
175 return 0;
176}
177#else /* !CONFIG_PM_DEBUG */
178static int hibernation_test(int level) { return 0; }
179#endif /* !CONFIG_PM_DEBUG */
180
181/**
182 * platform_begin - Call platform to start hibernation.
183 * @platform_mode: Whether or not to use the platform driver.
184 */
185static int platform_begin(int platform_mode)
186{
187 return (platform_mode && hibernation_ops) ?
188 hibernation_ops->begin(PMSG_FREEZE) : 0;
189}
190
191/**
192 * platform_end - Call platform to finish transition to the working state.
193 * @platform_mode: Whether or not to use the platform driver.
194 */
195static void platform_end(int platform_mode)
196{
197 if (platform_mode && hibernation_ops)
198 hibernation_ops->end();
199}
200
201/**
202 * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
203 * @platform_mode: Whether or not to use the platform driver.
204 *
205 * Use the platform driver to prepare the system for creating a hibernate image,
206 * if so configured, and return an error code if that fails.
207 */
208
209static int platform_pre_snapshot(int platform_mode)
210{
211 return (platform_mode && hibernation_ops) ?
212 hibernation_ops->pre_snapshot() : 0;
213}
214
215/**
216 * platform_leave - Call platform to prepare a transition to the working state.
217 * @platform_mode: Whether or not to use the platform driver.
218 *
219 * Use the platform driver prepare to prepare the machine for switching to the
220 * normal mode of operation.
221 *
222 * This routine is called on one CPU with interrupts disabled.
223 */
224static void platform_leave(int platform_mode)
225{
226 if (platform_mode && hibernation_ops)
227 hibernation_ops->leave();
228}
229
230/**
231 * platform_finish - Call platform to switch the system to the working state.
232 * @platform_mode: Whether or not to use the platform driver.
233 *
234 * Use the platform driver to switch the machine to the normal mode of
235 * operation.
236 *
237 * This routine must be called after platform_prepare().
238 */
239static void platform_finish(int platform_mode)
240{
241 if (platform_mode && hibernation_ops)
242 hibernation_ops->finish();
243}
244
245/**
246 * platform_pre_restore - Prepare for hibernate image restoration.
247 * @platform_mode: Whether or not to use the platform driver.
248 *
249 * Use the platform driver to prepare the system for resume from a hibernation
250 * image.
251 *
252 * If the restore fails after this function has been called,
253 * platform_restore_cleanup() must be called.
254 */
255static int platform_pre_restore(int platform_mode)
256{
257 return (platform_mode && hibernation_ops) ?
258 hibernation_ops->pre_restore() : 0;
259}
260
261/**
262 * platform_restore_cleanup - Switch to the working state after failing restore.
263 * @platform_mode: Whether or not to use the platform driver.
264 *
265 * Use the platform driver to switch the system to the normal mode of operation
266 * after a failing restore.
267 *
268 * If platform_pre_restore() has been called before the failing restore, this
269 * function must be called too, regardless of the result of
270 * platform_pre_restore().
271 */
272static void platform_restore_cleanup(int platform_mode)
273{
274 if (platform_mode && hibernation_ops)
275 hibernation_ops->restore_cleanup();
276}
277
278/**
279 * platform_recover - Recover from a failure to suspend devices.
280 * @platform_mode: Whether or not to use the platform driver.
281 */
282static void platform_recover(int platform_mode)
283{
284 if (platform_mode && hibernation_ops && hibernation_ops->recover)
285 hibernation_ops->recover();
286}
287
288/**
289 * swsusp_show_speed - Print time elapsed between two events during hibernation.
290 * @start: Starting event.
291 * @stop: Final event.
292 * @nr_pages: Number of memory pages processed between @start and @stop.
293 * @msg: Additional diagnostic message to print.
294 */
295void swsusp_show_speed(ktime_t start, ktime_t stop,
296 unsigned nr_pages, char *msg)
297{
298 ktime_t diff;
299 u64 elapsed_centisecs64;
300 unsigned int centisecs;
301 unsigned int k;
302 unsigned int kps;
303
304 diff = ktime_sub(stop, start);
305 elapsed_centisecs64 = ktime_divns(diff, 10*NSEC_PER_MSEC);
306 centisecs = elapsed_centisecs64;
307 if (centisecs == 0)
308 centisecs = 1; /* avoid div-by-zero */
309 k = nr_pages * (PAGE_SIZE / 1024);
310 kps = (k * 100) / centisecs;
311 pr_info("%s %u kbytes in %u.%02u seconds (%u.%02u MB/s)\n",
312 msg, k, centisecs / 100, centisecs % 100, kps / 1000,
313 (kps % 1000) / 10);
314}
315
316__weak int arch_resume_nosmt(void)
317{
318 return 0;
319}
320
321/**
322 * create_image - Create a hibernation image.
323 * @platform_mode: Whether or not to use the platform driver.
324 *
325 * Execute device drivers' "late" and "noirq" freeze callbacks, create a
326 * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
327 *
328 * Control reappears in this routine after the subsequent restore.
329 */
330static int create_image(int platform_mode)
331{
332 int error;
333
334 error = dpm_suspend_end(PMSG_FREEZE);
335 if (error) {
336 pr_err("Some devices failed to power down, aborting\n");
337 return error;
338 }
339
340 error = platform_pre_snapshot(platform_mode);
341 if (error || hibernation_test(TEST_PLATFORM))
342 goto Platform_finish;
343
344 error = pm_sleep_disable_secondary_cpus();
345 if (error || hibernation_test(TEST_CPUS))
346 goto Enable_cpus;
347
348 local_irq_disable();
349
350 system_state = SYSTEM_SUSPEND;
351
352 error = syscore_suspend();
353 if (error) {
354 pr_err("Some system devices failed to power down, aborting\n");
355 goto Enable_irqs;
356 }
357
358 if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
359 goto Power_up;
360
361 in_suspend = 1;
362 save_processor_state();
363 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true);
364 error = swsusp_arch_suspend();
365 /* Restore control flow magically appears here */
366 restore_processor_state();
367 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false);
368 if (error)
369 pr_err("Error %d creating image\n", error);
370
371 if (!in_suspend) {
372 events_check_enabled = false;
373 clear_or_poison_free_pages();
374 }
375
376 platform_leave(platform_mode);
377
378 Power_up:
379 syscore_resume();
380
381 Enable_irqs:
382 system_state = SYSTEM_RUNNING;
383 local_irq_enable();
384
385 Enable_cpus:
386 pm_sleep_enable_secondary_cpus();
387
388 /* Allow architectures to do nosmt-specific post-resume dances */
389 if (!in_suspend)
390 error = arch_resume_nosmt();
391
392 Platform_finish:
393 platform_finish(platform_mode);
394
395 dpm_resume_start(in_suspend ?
396 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
397
398 return error;
399}
400
401/**
402 * hibernation_snapshot - Quiesce devices and create a hibernation image.
403 * @platform_mode: If set, use platform driver to prepare for the transition.
404 *
405 * This routine must be called with system_transition_mutex held.
406 */
407int hibernation_snapshot(int platform_mode)
408{
409 pm_message_t msg;
410 int error;
411
412 pm_suspend_clear_flags();
413 error = platform_begin(platform_mode);
414 if (error)
415 goto Close;
416
417 error = dpm_prepare(PMSG_FREEZE);
418 if (error)
419 goto Complete;
420
421 /* Preallocate image memory before freezing kernel threads and shutting down devices. */
422 error = hibernate_preallocate_memory();
423 if (error)
424 goto Complete;
425
426 error = freeze_kernel_threads();
427 if (error)
428 goto Cleanup;
429
430 if (hibernation_test(TEST_FREEZER)) {
431
432 /*
433 * Indicate to the caller that we are returning due to a
434 * successful freezer test.
435 */
436 freezer_test_done = true;
437 goto Thaw;
438 }
439
440 console_suspend_all();
441 pm_restrict_gfp_mask();
442
443 error = dpm_suspend(PMSG_FREEZE);
444
445 if (error || hibernation_test(TEST_DEVICES))
446 platform_recover(platform_mode);
447 else
448 error = create_image(platform_mode);
449
450 /*
451 * In the case that we call create_image() above, the control
452 * returns here (1) after the image has been created or the
453 * image creation has failed and (2) after a successful restore.
454 */
455
456 /* We may need to release the preallocated image pages here. */
457 if (error || !in_suspend)
458 swsusp_free();
459
460 msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
461 dpm_resume(msg);
462
463 if (error || !in_suspend)
464 pm_restore_gfp_mask();
465
466 console_resume_all();
467 dpm_complete(msg);
468
469 Close:
470 platform_end(platform_mode);
471 return error;
472
473 Thaw:
474 thaw_kernel_threads();
475 Cleanup:
476 swsusp_free();
477 Complete:
478 dpm_complete(PMSG_RECOVER);
479 goto Close;
480}
481
482int __weak hibernate_resume_nonboot_cpu_disable(void)
483{
484 return suspend_disable_secondary_cpus();
485}
486
487/**
488 * resume_target_kernel - Restore system state from a hibernation image.
489 * @platform_mode: Whether or not to use the platform driver.
490 *
491 * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
492 * contents of highmem that have not been restored yet from the image and run
493 * the low-level code that will restore the remaining contents of memory and
494 * switch to the just restored target kernel.
495 */
496static int resume_target_kernel(bool platform_mode)
497{
498 int error;
499
500 error = dpm_suspend_end(PMSG_QUIESCE);
501 if (error) {
502 pr_err("Some devices failed to power down, aborting resume\n");
503 return error;
504 }
505
506 error = platform_pre_restore(platform_mode);
507 if (error)
508 goto Cleanup;
509
510 cpuidle_pause();
511
512 error = hibernate_resume_nonboot_cpu_disable();
513 if (error)
514 goto Enable_cpus;
515
516 local_irq_disable();
517 system_state = SYSTEM_SUSPEND;
518
519 error = syscore_suspend();
520 if (error)
521 goto Enable_irqs;
522
523 save_processor_state();
524 error = restore_highmem();
525 if (!error) {
526 error = swsusp_arch_resume();
527 /*
528 * The code below is only ever reached in case of a failure.
529 * Otherwise, execution continues at the place where
530 * swsusp_arch_suspend() was called.
531 */
532 BUG_ON(!error);
533 /*
534 * This call to restore_highmem() reverts the changes made by
535 * the previous one.
536 */
537 restore_highmem();
538 }
539 /*
540 * The only reason why swsusp_arch_resume() can fail is memory being
541 * very tight, so we have to free it as soon as we can to avoid
542 * subsequent failures.
543 */
544 swsusp_free();
545 restore_processor_state();
546 touch_softlockup_watchdog();
547
548 syscore_resume();
549
550 Enable_irqs:
551 system_state = SYSTEM_RUNNING;
552 local_irq_enable();
553
554 Enable_cpus:
555 pm_sleep_enable_secondary_cpus();
556
557 Cleanup:
558 platform_restore_cleanup(platform_mode);
559
560 dpm_resume_start(PMSG_RECOVER);
561
562 return error;
563}
564
565/**
566 * hibernation_restore - Quiesce devices and restore from a hibernation image.
567 * @platform_mode: If set, use platform driver to prepare for the transition.
568 *
569 * This routine must be called with system_transition_mutex held. If it is
570 * successful, control reappears in the restored target kernel in
571 * hibernation_snapshot().
572 */
573int hibernation_restore(int platform_mode)
574{
575 int error;
576
577 pm_prepare_console();
578 console_suspend_all();
579 error = dpm_suspend_start(PMSG_QUIESCE);
580 if (!error) {
581 error = resume_target_kernel(platform_mode);
582 /*
583 * The above should either succeed and jump to the new kernel,
584 * or return with an error. Otherwise things are just
585 * undefined, so let's be paranoid.
586 */
587 BUG_ON(!error);
588 }
589 dpm_resume_end(PMSG_RECOVER);
590 console_resume_all();
591 pm_restore_console();
592 return error;
593}
594
595/**
596 * hibernation_platform_enter - Power off the system using the platform driver.
597 */
598int hibernation_platform_enter(void)
599{
600 int error;
601
602 if (!hibernation_ops)
603 return -ENOSYS;
604
605 /*
606 * We have cancelled the power transition by running
607 * hibernation_ops->finish() before saving the image, so we should let
608 * the firmware know that we're going to enter the sleep state after all
609 */
610 error = hibernation_ops->begin(PMSG_HIBERNATE);
611 if (error)
612 goto Close;
613
614 entering_platform_hibernation = true;
615 console_suspend_all();
616 error = dpm_suspend_start(PMSG_HIBERNATE);
617 if (error) {
618 if (hibernation_ops->recover)
619 hibernation_ops->recover();
620 goto Resume_devices;
621 }
622
623 error = dpm_suspend_end(PMSG_HIBERNATE);
624 if (error)
625 goto Resume_devices;
626
627 error = hibernation_ops->prepare();
628 if (error)
629 goto Platform_finish;
630
631 error = pm_sleep_disable_secondary_cpus();
632 if (error)
633 goto Enable_cpus;
634
635 local_irq_disable();
636 system_state = SYSTEM_SUSPEND;
637
638 error = syscore_suspend();
639 if (error)
640 goto Enable_irqs;
641
642 if (pm_wakeup_pending()) {
643 error = -EAGAIN;
644 goto Power_up;
645 }
646
647 hibernation_ops->enter();
648 /* We should never get here */
649 while (1);
650
651 Power_up:
652 syscore_resume();
653 Enable_irqs:
654 system_state = SYSTEM_RUNNING;
655 local_irq_enable();
656
657 Enable_cpus:
658 pm_sleep_enable_secondary_cpus();
659
660 Platform_finish:
661 hibernation_ops->finish();
662
663 dpm_resume_start(PMSG_RESTORE);
664
665 Resume_devices:
666 entering_platform_hibernation = false;
667 dpm_resume_end(PMSG_RESTORE);
668 console_resume_all();
669
670 Close:
671 hibernation_ops->end();
672
673 return error;
674}
675
676/**
677 * power_down - Shut the machine down for hibernation.
678 *
679 * Use the platform driver, if configured, to put the system into the sleep
680 * state corresponding to hibernation, or try to power it off or reboot,
681 * depending on the value of hibernation_mode.
682 */
683static void power_down(void)
684{
685 int error;
686
687#ifdef CONFIG_SUSPEND
688 if (hibernation_mode == HIBERNATION_SUSPEND) {
689 error = suspend_devices_and_enter(mem_sleep_current);
690 if (!error)
691 goto exit;
692
693 hibernation_mode = hibernation_ops ? HIBERNATION_PLATFORM :
694 HIBERNATION_SHUTDOWN;
695 }
696#endif
697
698 switch (hibernation_mode) {
699 case HIBERNATION_REBOOT:
700 kernel_restart(NULL);
701 break;
702 case HIBERNATION_PLATFORM:
703 error = hibernation_platform_enter();
704 if (error == -EAGAIN || error == -EBUSY) {
705 events_check_enabled = false;
706 pr_info("Wakeup event detected during hibernation, rolling back.\n");
707 goto exit;
708 }
709 fallthrough;
710 case HIBERNATION_SHUTDOWN:
711 if (kernel_can_power_off()) {
712 entering_platform_hibernation = true;
713 kernel_power_off();
714 entering_platform_hibernation = false;
715 }
716 break;
717 }
718 kernel_halt();
719 /*
720 * Valid image is on the disk, if we continue we risk serious data
721 * corruption after resume.
722 */
723 pr_crit("Power down manually\n");
724 while (1)
725 cpu_relax();
726
727exit:
728 /* Restore swap signature. */
729 error = swsusp_unmark();
730 if (error)
731 pr_err("Swap will be unusable! Try swapon -a.\n");
732}
733
734static int load_image_and_restore(void)
735{
736 int error;
737 unsigned int flags;
738
739 pm_pr_dbg("Loading hibernation image.\n");
740
741 lock_device_hotplug();
742 error = create_basic_memory_bitmaps();
743 if (error) {
744 swsusp_close();
745 goto Unlock;
746 }
747
748 error = swsusp_read(&flags);
749 swsusp_close();
750 if (!error)
751 error = hibernation_restore(flags & SF_PLATFORM_MODE);
752
753 pr_err("Failed to load image, recovering.\n");
754 swsusp_free();
755 free_basic_memory_bitmaps();
756 Unlock:
757 unlock_device_hotplug();
758
759 return error;
760}
761
762#define COMPRESSION_ALGO_LZO "lzo"
763#define COMPRESSION_ALGO_LZ4 "lz4"
764
765/**
766 * hibernate - Carry out system hibernation, including saving the image.
767 */
768int hibernate(void)
769{
770 bool snapshot_test = false;
771 unsigned int sleep_flags;
772 int error;
773
774 if (!hibernation_available()) {
775 pm_pr_dbg("Hibernation not available.\n");
776 return -EPERM;
777 }
778
779 /*
780 * Query for the compression algorithm support if compression is enabled.
781 */
782 if (!nocompress) {
783 strscpy(hib_comp_algo, hibernate_compressor);
784 if (!crypto_has_acomp(hib_comp_algo, 0, CRYPTO_ALG_ASYNC)) {
785 pr_err("%s compression is not available\n", hib_comp_algo);
786 return -EOPNOTSUPP;
787 }
788 }
789
790 sleep_flags = lock_system_sleep();
791 /* The snapshot device should not be opened while we're running */
792 if (!hibernate_acquire()) {
793 error = -EBUSY;
794 goto Unlock;
795 }
796
797 pr_info("hibernation entry\n");
798 pm_prepare_console();
799 error = pm_notifier_call_chain_robust(PM_HIBERNATION_PREPARE, PM_POST_HIBERNATION);
800 if (error)
801 goto Restore;
802
803 error = pm_sleep_fs_sync();
804 if (error)
805 goto Notify;
806
807 filesystems_freeze(filesystem_freeze_enabled);
808
809 error = freeze_processes();
810 if (error)
811 goto Exit;
812
813 lock_device_hotplug();
814 /* Allocate memory management structures */
815 error = create_basic_memory_bitmaps();
816 if (error)
817 goto Thaw;
818
819 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
820 if (error || freezer_test_done)
821 goto Free_bitmaps;
822
823 if (in_suspend) {
824 unsigned int flags = 0;
825
826 if (hibernation_mode == HIBERNATION_PLATFORM)
827 flags |= SF_PLATFORM_MODE;
828 if (nocompress) {
829 flags |= SF_NOCOMPRESS_MODE;
830 } else {
831 flags |= SF_CRC32_MODE;
832
833 /*
834 * By default, LZO compression is enabled. Use SF_COMPRESSION_ALG_LZ4
835 * to override this behaviour and use LZ4.
836 *
837 * Refer kernel/power/power.h for more details
838 */
839
840 if (!strcmp(hib_comp_algo, COMPRESSION_ALGO_LZ4))
841 flags |= SF_COMPRESSION_ALG_LZ4;
842 else
843 flags |= SF_COMPRESSION_ALG_LZO;
844 }
845
846 pm_pr_dbg("Writing hibernation image.\n");
847 error = swsusp_write(flags);
848 swsusp_free();
849 if (!error) {
850 if (hibernation_mode == HIBERNATION_TEST_RESUME)
851 snapshot_test = true;
852 else
853 power_down();
854 }
855 in_suspend = 0;
856 pm_restore_gfp_mask();
857 } else {
858 pm_pr_dbg("Hibernation image restored successfully.\n");
859 }
860
861 Free_bitmaps:
862 free_basic_memory_bitmaps();
863 Thaw:
864 unlock_device_hotplug();
865 if (snapshot_test) {
866 pm_pr_dbg("Checking hibernation image\n");
867 error = swsusp_check(false);
868 if (!error)
869 error = load_image_and_restore();
870 }
871 thaw_processes();
872
873 /* Don't bother checking whether freezer_test_done is true */
874 freezer_test_done = false;
875 Exit:
876 filesystems_thaw();
877 Notify:
878 pm_notifier_call_chain(PM_POST_HIBERNATION);
879 Restore:
880 pm_restore_console();
881 hibernate_release();
882 Unlock:
883 unlock_system_sleep(sleep_flags);
884 pr_info("hibernation exit\n");
885
886 return error;
887}
888
889/**
890 * hibernate_quiet_exec - Execute a function with all devices frozen.
891 * @func: Function to execute.
892 * @data: Data pointer to pass to @func.
893 *
894 * Return the @func return value or an error code if it cannot be executed.
895 */
896int hibernate_quiet_exec(int (*func)(void *data), void *data)
897{
898 unsigned int sleep_flags;
899 int error;
900
901 sleep_flags = lock_system_sleep();
902
903 if (!hibernate_acquire()) {
904 error = -EBUSY;
905 goto unlock;
906 }
907
908 pm_prepare_console();
909
910 error = pm_notifier_call_chain_robust(PM_HIBERNATION_PREPARE, PM_POST_HIBERNATION);
911 if (error)
912 goto restore;
913
914 filesystems_freeze(filesystem_freeze_enabled);
915
916 error = freeze_processes();
917 if (error)
918 goto exit;
919
920 lock_device_hotplug();
921
922 pm_suspend_clear_flags();
923
924 error = platform_begin(true);
925 if (error)
926 goto thaw;
927
928 error = freeze_kernel_threads();
929 if (error)
930 goto thaw;
931
932 error = dpm_prepare(PMSG_FREEZE);
933 if (error)
934 goto dpm_complete;
935
936 console_suspend_all();
937
938 error = dpm_suspend(PMSG_FREEZE);
939 if (error)
940 goto dpm_resume;
941
942 error = dpm_suspend_end(PMSG_FREEZE);
943 if (error)
944 goto dpm_resume;
945
946 error = platform_pre_snapshot(true);
947 if (error)
948 goto skip;
949
950 error = func(data);
951
952skip:
953 platform_finish(true);
954
955 dpm_resume_start(PMSG_THAW);
956
957dpm_resume:
958 dpm_resume(PMSG_THAW);
959
960 console_resume_all();
961
962dpm_complete:
963 dpm_complete(PMSG_THAW);
964
965 thaw_kernel_threads();
966
967thaw:
968 platform_end(true);
969
970 unlock_device_hotplug();
971
972 thaw_processes();
973
974exit:
975 filesystems_thaw();
976 pm_notifier_call_chain(PM_POST_HIBERNATION);
977
978restore:
979 pm_restore_console();
980
981 hibernate_release();
982
983unlock:
984 unlock_system_sleep(sleep_flags);
985
986 return error;
987}
988EXPORT_SYMBOL_GPL(hibernate_quiet_exec);
989
990static int __init find_resume_device(void)
991{
992 if (!strlen(resume_file))
993 return -ENOENT;
994
995 pm_pr_dbg("Checking hibernation image partition %s\n", resume_file);
996
997 if (resume_delay) {
998 pr_info("Waiting %dsec before reading resume device ...\n",
999 resume_delay);
1000 ssleep(resume_delay);
1001 }
1002
1003 /* Check if the device is there */
1004 if (!early_lookup_bdev(resume_file, &swsusp_resume_device))
1005 return 0;
1006
1007 /*
1008 * Some device discovery might still be in progress; we need to wait for
1009 * this to finish.
1010 */
1011 wait_for_device_probe();
1012 if (resume_wait) {
1013 while (early_lookup_bdev(resume_file, &swsusp_resume_device))
1014 msleep(10);
1015 async_synchronize_full();
1016 }
1017
1018 return early_lookup_bdev(resume_file, &swsusp_resume_device);
1019}
1020
1021static int software_resume(void)
1022{
1023 int error;
1024
1025 pm_pr_dbg("Hibernation image partition %d:%d present\n",
1026 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
1027
1028 pm_pr_dbg("Looking for hibernation image.\n");
1029
1030 mutex_lock(&system_transition_mutex);
1031 error = swsusp_check(true);
1032 if (error)
1033 goto Unlock;
1034
1035 /*
1036 * Check if the hibernation image is compressed. If so, query for
1037 * the algorithm support.
1038 */
1039 if (!(swsusp_header_flags & SF_NOCOMPRESS_MODE)) {
1040 if (swsusp_header_flags & SF_COMPRESSION_ALG_LZ4)
1041 strscpy(hib_comp_algo, COMPRESSION_ALGO_LZ4);
1042 else
1043 strscpy(hib_comp_algo, COMPRESSION_ALGO_LZO);
1044 if (!crypto_has_acomp(hib_comp_algo, 0, CRYPTO_ALG_ASYNC)) {
1045 pr_err("%s compression is not available\n", hib_comp_algo);
1046 error = -EOPNOTSUPP;
1047 goto Unlock;
1048 }
1049 }
1050
1051 /* The snapshot device should not be opened while we're running */
1052 if (!hibernate_acquire()) {
1053 error = -EBUSY;
1054 swsusp_close();
1055 goto Unlock;
1056 }
1057
1058 pr_info("resume from hibernation\n");
1059 pm_prepare_console();
1060 error = pm_notifier_call_chain_robust(PM_RESTORE_PREPARE, PM_POST_RESTORE);
1061 if (error)
1062 goto Restore;
1063
1064 filesystems_freeze(filesystem_freeze_enabled);
1065
1066 pm_pr_dbg("Preparing processes for hibernation restore.\n");
1067 error = freeze_processes();
1068 if (error) {
1069 filesystems_thaw();
1070 goto Close_Finish;
1071 }
1072
1073 error = freeze_kernel_threads();
1074 if (error) {
1075 thaw_processes();
1076 filesystems_thaw();
1077 goto Close_Finish;
1078 }
1079
1080 error = load_image_and_restore();
1081 thaw_processes();
1082 filesystems_thaw();
1083 Finish:
1084 pm_notifier_call_chain(PM_POST_RESTORE);
1085 Restore:
1086 pm_restore_console();
1087 pr_info("resume failed (%d)\n", error);
1088 hibernate_release();
1089 /* For success case, the suspend path will release the lock */
1090 Unlock:
1091 mutex_unlock(&system_transition_mutex);
1092 pm_pr_dbg("Hibernation image not present or could not be loaded.\n");
1093 return error;
1094 Close_Finish:
1095 swsusp_close();
1096 goto Finish;
1097}
1098
1099/**
1100 * software_resume_initcall - Resume from a saved hibernation image.
1101 *
1102 * This routine is called as a late initcall, when all devices have been
1103 * discovered and initialized already.
1104 *
1105 * The image reading code is called to see if there is a hibernation image
1106 * available for reading. If that is the case, devices are quiesced and the
1107 * contents of memory is restored from the saved image.
1108 *
1109 * If this is successful, control reappears in the restored target kernel in
1110 * hibernation_snapshot() which returns to hibernate(). Otherwise, the routine
1111 * attempts to recover gracefully and make the kernel return to the normal mode
1112 * of operation.
1113 */
1114static int __init software_resume_initcall(void)
1115{
1116 /*
1117 * If the user said "noresume".. bail out early.
1118 */
1119 if (noresume || !hibernation_available())
1120 return 0;
1121
1122 if (!swsusp_resume_device) {
1123 int error = find_resume_device();
1124
1125 if (error)
1126 return error;
1127 }
1128
1129 return software_resume();
1130}
1131late_initcall_sync(software_resume_initcall);
1132
1133
1134static const char * const hibernation_modes[] = {
1135 [HIBERNATION_PLATFORM] = "platform",
1136 [HIBERNATION_SHUTDOWN] = "shutdown",
1137 [HIBERNATION_REBOOT] = "reboot",
1138#ifdef CONFIG_SUSPEND
1139 [HIBERNATION_SUSPEND] = "suspend",
1140#endif
1141 [HIBERNATION_TEST_RESUME] = "test_resume",
1142};
1143
1144/*
1145 * /sys/power/disk - Control hibernation mode.
1146 *
1147 * Hibernation can be handled in several ways. There are a few different ways
1148 * to put the system into the sleep state: using the platform driver (e.g. ACPI
1149 * or other hibernation_ops), powering it off or rebooting it (for testing
1150 * mostly).
1151 *
1152 * The sysfs file /sys/power/disk provides an interface for selecting the
1153 * hibernation mode to use. Reading from this file causes the available modes
1154 * to be printed. There are 3 modes that can be supported:
1155 *
1156 * 'platform'
1157 * 'shutdown'
1158 * 'reboot'
1159 *
1160 * If a platform hibernation driver is in use, 'platform' will be supported
1161 * and will be used by default. Otherwise, 'shutdown' will be used by default.
1162 * The selected option (i.e. the one corresponding to the current value of
1163 * hibernation_mode) is enclosed by a square bracket.
1164 *
1165 * To select a given hibernation mode it is necessary to write the mode's
1166 * string representation (as returned by reading from /sys/power/disk) back
1167 * into /sys/power/disk.
1168 */
1169
1170static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
1171 char *buf)
1172{
1173 ssize_t count = 0;
1174 int i;
1175
1176 if (!hibernation_available())
1177 return sysfs_emit(buf, "[disabled]\n");
1178
1179 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
1180 if (!hibernation_modes[i])
1181 continue;
1182 switch (i) {
1183 case HIBERNATION_SHUTDOWN:
1184 case HIBERNATION_REBOOT:
1185#ifdef CONFIG_SUSPEND
1186 case HIBERNATION_SUSPEND:
1187#endif
1188 case HIBERNATION_TEST_RESUME:
1189 break;
1190 case HIBERNATION_PLATFORM:
1191 if (hibernation_ops)
1192 break;
1193 /* not a valid mode, continue with loop */
1194 continue;
1195 }
1196 if (i == hibernation_mode)
1197 count += sysfs_emit_at(buf, count, "[%s] ", hibernation_modes[i]);
1198 else
1199 count += sysfs_emit_at(buf, count, "%s ", hibernation_modes[i]);
1200 }
1201
1202 /* Convert the last space to a newline if needed. */
1203 if (count > 0)
1204 buf[count - 1] = '\n';
1205
1206 return count;
1207}
1208
1209static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
1210 const char *buf, size_t n)
1211{
1212 int mode = HIBERNATION_INVALID;
1213 unsigned int sleep_flags;
1214 int error = 0;
1215 int len;
1216 char *p;
1217 int i;
1218
1219 if (!hibernation_available())
1220 return -EPERM;
1221
1222 p = memchr(buf, '\n', n);
1223 len = p ? p - buf : n;
1224
1225 sleep_flags = lock_system_sleep();
1226 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
1227 if (len == strlen(hibernation_modes[i])
1228 && !strncmp(buf, hibernation_modes[i], len)) {
1229 mode = i;
1230 break;
1231 }
1232 }
1233 if (mode != HIBERNATION_INVALID) {
1234 switch (mode) {
1235 case HIBERNATION_SHUTDOWN:
1236 case HIBERNATION_REBOOT:
1237#ifdef CONFIG_SUSPEND
1238 case HIBERNATION_SUSPEND:
1239#endif
1240 case HIBERNATION_TEST_RESUME:
1241 hibernation_mode = mode;
1242 break;
1243 case HIBERNATION_PLATFORM:
1244 if (hibernation_ops)
1245 hibernation_mode = mode;
1246 else
1247 error = -EINVAL;
1248 }
1249 } else
1250 error = -EINVAL;
1251
1252 if (!error)
1253 pm_pr_dbg("Hibernation mode set to '%s'\n",
1254 hibernation_modes[mode]);
1255 unlock_system_sleep(sleep_flags);
1256 return error ? error : n;
1257}
1258
1259power_attr(disk);
1260
1261static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
1262 char *buf)
1263{
1264 return sysfs_emit(buf, "%d:%d\n", MAJOR(swsusp_resume_device),
1265 MINOR(swsusp_resume_device));
1266}
1267
1268static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
1269 const char *buf, size_t n)
1270{
1271 unsigned int sleep_flags;
1272 int len = n;
1273 char *name;
1274 dev_t dev;
1275 int error;
1276
1277 if (!hibernation_available())
1278 return n;
1279
1280 if (len && buf[len-1] == '\n')
1281 len--;
1282 name = kstrndup(buf, len, GFP_KERNEL);
1283 if (!name)
1284 return -ENOMEM;
1285
1286 error = lookup_bdev(name, &dev);
1287 if (error) {
1288 unsigned maj, min, offset;
1289 char *p, dummy;
1290
1291 error = 0;
1292 if (sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2 ||
1293 sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset,
1294 &dummy) == 3) {
1295 dev = MKDEV(maj, min);
1296 if (maj != MAJOR(dev) || min != MINOR(dev))
1297 error = -EINVAL;
1298 } else {
1299 dev = new_decode_dev(simple_strtoul(name, &p, 16));
1300 if (*p)
1301 error = -EINVAL;
1302 }
1303 }
1304 kfree(name);
1305 if (error)
1306 return error;
1307
1308 sleep_flags = lock_system_sleep();
1309 swsusp_resume_device = dev;
1310 unlock_system_sleep(sleep_flags);
1311
1312 pm_pr_dbg("Configured hibernation resume from disk to %u\n",
1313 swsusp_resume_device);
1314 noresume = 0;
1315 software_resume();
1316 return n;
1317}
1318
1319power_attr(resume);
1320
1321static ssize_t resume_offset_show(struct kobject *kobj,
1322 struct kobj_attribute *attr, char *buf)
1323{
1324 return sysfs_emit(buf, "%llu\n", (unsigned long long)swsusp_resume_block);
1325}
1326
1327static ssize_t resume_offset_store(struct kobject *kobj,
1328 struct kobj_attribute *attr, const char *buf,
1329 size_t n)
1330{
1331 unsigned long long offset;
1332 int rc;
1333
1334 rc = kstrtoull(buf, 0, &offset);
1335 if (rc)
1336 return rc;
1337 swsusp_resume_block = offset;
1338
1339 return n;
1340}
1341
1342power_attr(resume_offset);
1343
1344static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
1345 char *buf)
1346{
1347 return sysfs_emit(buf, "%lu\n", image_size);
1348}
1349
1350static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
1351 const char *buf, size_t n)
1352{
1353 unsigned long size;
1354
1355 if (sscanf(buf, "%lu", &size) == 1) {
1356 image_size = size;
1357 return n;
1358 }
1359
1360 return -EINVAL;
1361}
1362
1363power_attr(image_size);
1364
1365static ssize_t reserved_size_show(struct kobject *kobj,
1366 struct kobj_attribute *attr, char *buf)
1367{
1368 return sysfs_emit(buf, "%lu\n", reserved_size);
1369}
1370
1371static ssize_t reserved_size_store(struct kobject *kobj,
1372 struct kobj_attribute *attr,
1373 const char *buf, size_t n)
1374{
1375 unsigned long size;
1376
1377 if (sscanf(buf, "%lu", &size) == 1) {
1378 reserved_size = size;
1379 return n;
1380 }
1381
1382 return -EINVAL;
1383}
1384
1385power_attr(reserved_size);
1386
1387static struct attribute *g[] = {
1388 &disk_attr.attr,
1389 &resume_offset_attr.attr,
1390 &resume_attr.attr,
1391 &image_size_attr.attr,
1392 &reserved_size_attr.attr,
1393 NULL,
1394};
1395
1396
1397static const struct attribute_group attr_group = {
1398 .attrs = g,
1399};
1400
1401
1402static int __init pm_disk_init(void)
1403{
1404 return sysfs_create_group(power_kobj, &attr_group);
1405}
1406
1407core_initcall(pm_disk_init);
1408
1409
1410static int __init resume_setup(char *str)
1411{
1412 if (noresume)
1413 return 1;
1414
1415 strscpy(resume_file, str);
1416 return 1;
1417}
1418
1419static int __init resume_offset_setup(char *str)
1420{
1421 unsigned long long offset;
1422
1423 if (noresume)
1424 return 1;
1425
1426 if (sscanf(str, "%llu", &offset) == 1)
1427 swsusp_resume_block = offset;
1428
1429 return 1;
1430}
1431
1432static int __init hibernate_setup(char *str)
1433{
1434 if (!strncmp(str, "noresume", 8)) {
1435 noresume = 1;
1436 } else if (!strncmp(str, "nocompress", 10)) {
1437 nocompress = 1;
1438 } else if (!strncmp(str, "no", 2)) {
1439 noresume = 1;
1440 nohibernate = 1;
1441 } else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)
1442 && !strncmp(str, "protect_image", 13)) {
1443 enable_restore_image_protection();
1444 }
1445 return 1;
1446}
1447
1448static int __init noresume_setup(char *str)
1449{
1450 noresume = 1;
1451 return 1;
1452}
1453
1454static int __init resumewait_setup(char *str)
1455{
1456 resume_wait = 1;
1457 return 1;
1458}
1459
1460static int __init resumedelay_setup(char *str)
1461{
1462 int rc = kstrtouint(str, 0, &resume_delay);
1463
1464 if (rc)
1465 pr_warn("resumedelay: bad option string '%s'\n", str);
1466 return 1;
1467}
1468
1469static int __init nohibernate_setup(char *str)
1470{
1471 noresume = 1;
1472 nohibernate = 1;
1473 return 1;
1474}
1475
1476static const char * const comp_alg_enabled[] = {
1477#if IS_ENABLED(CONFIG_CRYPTO_LZO)
1478 COMPRESSION_ALGO_LZO,
1479#endif
1480#if IS_ENABLED(CONFIG_CRYPTO_LZ4)
1481 COMPRESSION_ALGO_LZ4,
1482#endif
1483};
1484
1485static int hibernate_compressor_param_set(const char *compressor,
1486 const struct kernel_param *kp)
1487{
1488 int index, ret;
1489
1490 if (!mutex_trylock(&system_transition_mutex))
1491 return -EBUSY;
1492
1493 index = sysfs_match_string(comp_alg_enabled, compressor);
1494 if (index >= 0) {
1495 ret = param_set_copystring(comp_alg_enabled[index], kp);
1496 if (!ret)
1497 strscpy(hib_comp_algo, comp_alg_enabled[index]);
1498 } else {
1499 ret = index;
1500 }
1501
1502 mutex_unlock(&system_transition_mutex);
1503
1504 if (ret)
1505 pr_debug("Cannot set specified compressor %s\n",
1506 compressor);
1507
1508 return ret;
1509}
1510
1511static const struct kernel_param_ops hibernate_compressor_param_ops = {
1512 .set = hibernate_compressor_param_set,
1513 .get = param_get_string,
1514};
1515
1516static struct kparam_string hibernate_compressor_param_string = {
1517 .maxlen = sizeof(hibernate_compressor),
1518 .string = hibernate_compressor,
1519};
1520
1521module_param_cb(compressor, &hibernate_compressor_param_ops,
1522 &hibernate_compressor_param_string, 0644);
1523MODULE_PARM_DESC(compressor,
1524 "Compression algorithm to be used with hibernation");
1525
1526__setup("noresume", noresume_setup);
1527__setup("resume_offset=", resume_offset_setup);
1528__setup("resume=", resume_setup);
1529__setup("hibernate=", hibernate_setup);
1530__setup("resumewait", resumewait_setup);
1531__setup("resumedelay=", resumedelay_setup);
1532__setup("nohibernate", nohibernate_setup);