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