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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * kernel/power/hibernate.c - Hibernation (a.k.a suspend-to-disk) support.
4 *
5 * Copyright (c) 2003 Patrick Mochel
6 * Copyright (c) 2003 Open Source Development Lab
7 * Copyright (c) 2004 Pavel Machek <pavel@ucw.cz>
8 * Copyright (c) 2009 Rafael J. Wysocki, Novell Inc.
9 * Copyright (C) 2012 Bojan Smojver <bojan@rexursive.com>
10 */
11
12#define pr_fmt(fmt) "PM: " fmt
13
14#include <linux/export.h>
15#include <linux/suspend.h>
16#include <linux/reboot.h>
17#include <linux/string.h>
18#include <linux/device.h>
19#include <linux/async.h>
20#include <linux/delay.h>
21#include <linux/fs.h>
22#include <linux/mount.h>
23#include <linux/pm.h>
24#include <linux/nmi.h>
25#include <linux/console.h>
26#include <linux/cpu.h>
27#include <linux/freezer.h>
28#include <linux/gfp.h>
29#include <linux/syscore_ops.h>
30#include <linux/ctype.h>
31#include <linux/genhd.h>
32#include <linux/ktime.h>
33#include <linux/security.h>
34#include <trace/events/power.h>
35
36#include "power.h"
37
38
39static int nocompress;
40static int noresume;
41static int nohibernate;
42static int resume_wait;
43static unsigned int resume_delay;
44static char resume_file[256] = CONFIG_PM_STD_PARTITION;
45dev_t swsusp_resume_device;
46sector_t swsusp_resume_block;
47__visible int in_suspend __nosavedata;
48
49enum {
50 HIBERNATION_INVALID,
51 HIBERNATION_PLATFORM,
52 HIBERNATION_SHUTDOWN,
53 HIBERNATION_REBOOT,
54#ifdef CONFIG_SUSPEND
55 HIBERNATION_SUSPEND,
56#endif
57 HIBERNATION_TEST_RESUME,
58 /* keep last */
59 __HIBERNATION_AFTER_LAST
60};
61#define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
62#define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
63
64static int hibernation_mode = HIBERNATION_SHUTDOWN;
65
66bool freezer_test_done;
67
68static const struct platform_hibernation_ops *hibernation_ops;
69
70bool hibernation_available(void)
71{
72 return nohibernate == 0 && !security_locked_down(LOCKDOWN_HIBERNATION);
73}
74
75/**
76 * hibernation_set_ops - Set the global hibernate operations.
77 * @ops: Hibernation operations to use in subsequent hibernation transitions.
78 */
79void hibernation_set_ops(const struct platform_hibernation_ops *ops)
80{
81 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
82 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
83 && ops->restore_cleanup && ops->leave)) {
84 WARN_ON(1);
85 return;
86 }
87 lock_system_sleep();
88 hibernation_ops = ops;
89 if (ops)
90 hibernation_mode = HIBERNATION_PLATFORM;
91 else if (hibernation_mode == HIBERNATION_PLATFORM)
92 hibernation_mode = HIBERNATION_SHUTDOWN;
93
94 unlock_system_sleep();
95}
96EXPORT_SYMBOL_GPL(hibernation_set_ops);
97
98static bool entering_platform_hibernation;
99
100bool system_entering_hibernation(void)
101{
102 return entering_platform_hibernation;
103}
104EXPORT_SYMBOL(system_entering_hibernation);
105
106#ifdef CONFIG_PM_DEBUG
107static void hibernation_debug_sleep(void)
108{
109 pr_info("hibernation debug: Waiting for 5 seconds.\n");
110 mdelay(5000);
111}
112
113static int hibernation_test(int level)
114{
115 if (pm_test_level == level) {
116 hibernation_debug_sleep();
117 return 1;
118 }
119 return 0;
120}
121#else /* !CONFIG_PM_DEBUG */
122static int hibernation_test(int level) { return 0; }
123#endif /* !CONFIG_PM_DEBUG */
124
125/**
126 * platform_begin - Call platform to start hibernation.
127 * @platform_mode: Whether or not to use the platform driver.
128 */
129static int platform_begin(int platform_mode)
130{
131 return (platform_mode && hibernation_ops) ?
132 hibernation_ops->begin(PMSG_FREEZE) : 0;
133}
134
135/**
136 * platform_end - Call platform to finish transition to the working state.
137 * @platform_mode: Whether or not to use the platform driver.
138 */
139static void platform_end(int platform_mode)
140{
141 if (platform_mode && hibernation_ops)
142 hibernation_ops->end();
143}
144
145/**
146 * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
147 * @platform_mode: Whether or not to use the platform driver.
148 *
149 * Use the platform driver to prepare the system for creating a hibernate image,
150 * if so configured, and return an error code if that fails.
151 */
152
153static int platform_pre_snapshot(int platform_mode)
154{
155 return (platform_mode && hibernation_ops) ?
156 hibernation_ops->pre_snapshot() : 0;
157}
158
159/**
160 * platform_leave - Call platform to prepare a transition to the working state.
161 * @platform_mode: Whether or not to use the platform driver.
162 *
163 * Use the platform driver prepare to prepare the machine for switching to the
164 * normal mode of operation.
165 *
166 * This routine is called on one CPU with interrupts disabled.
167 */
168static void platform_leave(int platform_mode)
169{
170 if (platform_mode && hibernation_ops)
171 hibernation_ops->leave();
172}
173
174/**
175 * platform_finish - Call platform to switch the system to the working state.
176 * @platform_mode: Whether or not to use the platform driver.
177 *
178 * Use the platform driver to switch the machine to the normal mode of
179 * operation.
180 *
181 * This routine must be called after platform_prepare().
182 */
183static void platform_finish(int platform_mode)
184{
185 if (platform_mode && hibernation_ops)
186 hibernation_ops->finish();
187}
188
189/**
190 * platform_pre_restore - Prepare for hibernate image restoration.
191 * @platform_mode: Whether or not to use the platform driver.
192 *
193 * Use the platform driver to prepare the system for resume from a hibernation
194 * image.
195 *
196 * If the restore fails after this function has been called,
197 * platform_restore_cleanup() must be called.
198 */
199static int platform_pre_restore(int platform_mode)
200{
201 return (platform_mode && hibernation_ops) ?
202 hibernation_ops->pre_restore() : 0;
203}
204
205/**
206 * platform_restore_cleanup - Switch to the working state after failing restore.
207 * @platform_mode: Whether or not to use the platform driver.
208 *
209 * Use the platform driver to switch the system to the normal mode of operation
210 * after a failing restore.
211 *
212 * If platform_pre_restore() has been called before the failing restore, this
213 * function must be called too, regardless of the result of
214 * platform_pre_restore().
215 */
216static void platform_restore_cleanup(int platform_mode)
217{
218 if (platform_mode && hibernation_ops)
219 hibernation_ops->restore_cleanup();
220}
221
222/**
223 * platform_recover - Recover from a failure to suspend devices.
224 * @platform_mode: Whether or not to use the platform driver.
225 */
226static void platform_recover(int platform_mode)
227{
228 if (platform_mode && hibernation_ops && hibernation_ops->recover)
229 hibernation_ops->recover();
230}
231
232/**
233 * swsusp_show_speed - Print time elapsed between two events during hibernation.
234 * @start: Starting event.
235 * @stop: Final event.
236 * @nr_pages: Number of memory pages processed between @start and @stop.
237 * @msg: Additional diagnostic message to print.
238 */
239void swsusp_show_speed(ktime_t start, ktime_t stop,
240 unsigned nr_pages, char *msg)
241{
242 ktime_t diff;
243 u64 elapsed_centisecs64;
244 unsigned int centisecs;
245 unsigned int k;
246 unsigned int kps;
247
248 diff = ktime_sub(stop, start);
249 elapsed_centisecs64 = ktime_divns(diff, 10*NSEC_PER_MSEC);
250 centisecs = elapsed_centisecs64;
251 if (centisecs == 0)
252 centisecs = 1; /* avoid div-by-zero */
253 k = nr_pages * (PAGE_SIZE / 1024);
254 kps = (k * 100) / centisecs;
255 pr_info("%s %u kbytes in %u.%02u seconds (%u.%02u MB/s)\n",
256 msg, k, centisecs / 100, centisecs % 100, kps / 1000,
257 (kps % 1000) / 10);
258}
259
260__weak int arch_resume_nosmt(void)
261{
262 return 0;
263}
264
265/**
266 * create_image - Create a hibernation image.
267 * @platform_mode: Whether or not to use the platform driver.
268 *
269 * Execute device drivers' "late" and "noirq" freeze callbacks, create a
270 * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
271 *
272 * Control reappears in this routine after the subsequent restore.
273 */
274static int create_image(int platform_mode)
275{
276 int error;
277
278 error = dpm_suspend_end(PMSG_FREEZE);
279 if (error) {
280 pr_err("Some devices failed to power down, aborting hibernation\n");
281 return error;
282 }
283
284 error = platform_pre_snapshot(platform_mode);
285 if (error || hibernation_test(TEST_PLATFORM))
286 goto Platform_finish;
287
288 error = suspend_disable_secondary_cpus();
289 if (error || hibernation_test(TEST_CPUS))
290 goto Enable_cpus;
291
292 local_irq_disable();
293
294 system_state = SYSTEM_SUSPEND;
295
296 error = syscore_suspend();
297 if (error) {
298 pr_err("Some system devices failed to power down, aborting hibernation\n");
299 goto Enable_irqs;
300 }
301
302 if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
303 goto Power_up;
304
305 in_suspend = 1;
306 save_processor_state();
307 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true);
308 error = swsusp_arch_suspend();
309 /* Restore control flow magically appears here */
310 restore_processor_state();
311 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false);
312 if (error)
313 pr_err("Error %d creating hibernation image\n", error);
314
315 if (!in_suspend) {
316 events_check_enabled = false;
317 clear_free_pages();
318 }
319
320 platform_leave(platform_mode);
321
322 Power_up:
323 syscore_resume();
324
325 Enable_irqs:
326 system_state = SYSTEM_RUNNING;
327 local_irq_enable();
328
329 Enable_cpus:
330 suspend_enable_secondary_cpus();
331
332 /* Allow architectures to do nosmt-specific post-resume dances */
333 if (!in_suspend)
334 error = arch_resume_nosmt();
335
336 Platform_finish:
337 platform_finish(platform_mode);
338
339 dpm_resume_start(in_suspend ?
340 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
341
342 return error;
343}
344
345/**
346 * hibernation_snapshot - Quiesce devices and create a hibernation image.
347 * @platform_mode: If set, use platform driver to prepare for the transition.
348 *
349 * This routine must be called with system_transition_mutex held.
350 */
351int hibernation_snapshot(int platform_mode)
352{
353 pm_message_t msg;
354 int error;
355
356 pm_suspend_clear_flags();
357 error = platform_begin(platform_mode);
358 if (error)
359 goto Close;
360
361 /* Preallocate image memory before shutting down devices. */
362 error = hibernate_preallocate_memory();
363 if (error)
364 goto Close;
365
366 error = freeze_kernel_threads();
367 if (error)
368 goto Cleanup;
369
370 if (hibernation_test(TEST_FREEZER)) {
371
372 /*
373 * Indicate to the caller that we are returning due to a
374 * successful freezer test.
375 */
376 freezer_test_done = true;
377 goto Thaw;
378 }
379
380 error = dpm_prepare(PMSG_FREEZE);
381 if (error) {
382 dpm_complete(PMSG_RECOVER);
383 goto Thaw;
384 }
385
386 suspend_console();
387 pm_restrict_gfp_mask();
388
389 error = dpm_suspend(PMSG_FREEZE);
390
391 if (error || hibernation_test(TEST_DEVICES))
392 platform_recover(platform_mode);
393 else
394 error = create_image(platform_mode);
395
396 /*
397 * In the case that we call create_image() above, the control
398 * returns here (1) after the image has been created or the
399 * image creation has failed and (2) after a successful restore.
400 */
401
402 /* We may need to release the preallocated image pages here. */
403 if (error || !in_suspend)
404 swsusp_free();
405
406 msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
407 dpm_resume(msg);
408
409 if (error || !in_suspend)
410 pm_restore_gfp_mask();
411
412 resume_console();
413 dpm_complete(msg);
414
415 Close:
416 platform_end(platform_mode);
417 return error;
418
419 Thaw:
420 thaw_kernel_threads();
421 Cleanup:
422 swsusp_free();
423 goto Close;
424}
425
426int __weak hibernate_resume_nonboot_cpu_disable(void)
427{
428 return suspend_disable_secondary_cpus();
429}
430
431/**
432 * resume_target_kernel - Restore system state from a hibernation image.
433 * @platform_mode: Whether or not to use the platform driver.
434 *
435 * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
436 * contents of highmem that have not been restored yet from the image and run
437 * the low-level code that will restore the remaining contents of memory and
438 * switch to the just restored target kernel.
439 */
440static int resume_target_kernel(bool platform_mode)
441{
442 int error;
443
444 error = dpm_suspend_end(PMSG_QUIESCE);
445 if (error) {
446 pr_err("Some devices failed to power down, aborting resume\n");
447 return error;
448 }
449
450 error = platform_pre_restore(platform_mode);
451 if (error)
452 goto Cleanup;
453
454 error = hibernate_resume_nonboot_cpu_disable();
455 if (error)
456 goto Enable_cpus;
457
458 local_irq_disable();
459 system_state = SYSTEM_SUSPEND;
460
461 error = syscore_suspend();
462 if (error)
463 goto Enable_irqs;
464
465 save_processor_state();
466 error = restore_highmem();
467 if (!error) {
468 error = swsusp_arch_resume();
469 /*
470 * The code below is only ever reached in case of a failure.
471 * Otherwise, execution continues at the place where
472 * swsusp_arch_suspend() was called.
473 */
474 BUG_ON(!error);
475 /*
476 * This call to restore_highmem() reverts the changes made by
477 * the previous one.
478 */
479 restore_highmem();
480 }
481 /*
482 * The only reason why swsusp_arch_resume() can fail is memory being
483 * very tight, so we have to free it as soon as we can to avoid
484 * subsequent failures.
485 */
486 swsusp_free();
487 restore_processor_state();
488 touch_softlockup_watchdog();
489
490 syscore_resume();
491
492 Enable_irqs:
493 system_state = SYSTEM_RUNNING;
494 local_irq_enable();
495
496 Enable_cpus:
497 suspend_enable_secondary_cpus();
498
499 Cleanup:
500 platform_restore_cleanup(platform_mode);
501
502 dpm_resume_start(PMSG_RECOVER);
503
504 return error;
505}
506
507/**
508 * hibernation_restore - Quiesce devices and restore from a hibernation image.
509 * @platform_mode: If set, use platform driver to prepare for the transition.
510 *
511 * This routine must be called with system_transition_mutex held. If it is
512 * successful, control reappears in the restored target kernel in
513 * hibernation_snapshot().
514 */
515int hibernation_restore(int platform_mode)
516{
517 int error;
518
519 pm_prepare_console();
520 suspend_console();
521 pm_restrict_gfp_mask();
522 error = dpm_suspend_start(PMSG_QUIESCE);
523 if (!error) {
524 error = resume_target_kernel(platform_mode);
525 /*
526 * The above should either succeed and jump to the new kernel,
527 * or return with an error. Otherwise things are just
528 * undefined, so let's be paranoid.
529 */
530 BUG_ON(!error);
531 }
532 dpm_resume_end(PMSG_RECOVER);
533 pm_restore_gfp_mask();
534 resume_console();
535 pm_restore_console();
536 return error;
537}
538
539/**
540 * hibernation_platform_enter - Power off the system using the platform driver.
541 */
542int hibernation_platform_enter(void)
543{
544 int error;
545
546 if (!hibernation_ops)
547 return -ENOSYS;
548
549 /*
550 * We have cancelled the power transition by running
551 * hibernation_ops->finish() before saving the image, so we should let
552 * the firmware know that we're going to enter the sleep state after all
553 */
554 error = hibernation_ops->begin(PMSG_HIBERNATE);
555 if (error)
556 goto Close;
557
558 entering_platform_hibernation = true;
559 suspend_console();
560 error = dpm_suspend_start(PMSG_HIBERNATE);
561 if (error) {
562 if (hibernation_ops->recover)
563 hibernation_ops->recover();
564 goto Resume_devices;
565 }
566
567 error = dpm_suspend_end(PMSG_HIBERNATE);
568 if (error)
569 goto Resume_devices;
570
571 error = hibernation_ops->prepare();
572 if (error)
573 goto Platform_finish;
574
575 error = suspend_disable_secondary_cpus();
576 if (error)
577 goto Enable_cpus;
578
579 local_irq_disable();
580 system_state = SYSTEM_SUSPEND;
581 syscore_suspend();
582 if (pm_wakeup_pending()) {
583 error = -EAGAIN;
584 goto Power_up;
585 }
586
587 hibernation_ops->enter();
588 /* We should never get here */
589 while (1);
590
591 Power_up:
592 syscore_resume();
593 system_state = SYSTEM_RUNNING;
594 local_irq_enable();
595
596 Enable_cpus:
597 suspend_enable_secondary_cpus();
598
599 Platform_finish:
600 hibernation_ops->finish();
601
602 dpm_resume_start(PMSG_RESTORE);
603
604 Resume_devices:
605 entering_platform_hibernation = false;
606 dpm_resume_end(PMSG_RESTORE);
607 resume_console();
608
609 Close:
610 hibernation_ops->end();
611
612 return error;
613}
614
615/**
616 * power_down - Shut the machine down for hibernation.
617 *
618 * Use the platform driver, if configured, to put the system into the sleep
619 * state corresponding to hibernation, or try to power it off or reboot,
620 * depending on the value of hibernation_mode.
621 */
622static void power_down(void)
623{
624#ifdef CONFIG_SUSPEND
625 int error;
626
627 if (hibernation_mode == HIBERNATION_SUSPEND) {
628 error = suspend_devices_and_enter(PM_SUSPEND_MEM);
629 if (error) {
630 hibernation_mode = hibernation_ops ?
631 HIBERNATION_PLATFORM :
632 HIBERNATION_SHUTDOWN;
633 } else {
634 /* Restore swap signature. */
635 error = swsusp_unmark();
636 if (error)
637 pr_err("Swap will be unusable! Try swapon -a.\n");
638
639 return;
640 }
641 }
642#endif
643
644 switch (hibernation_mode) {
645 case HIBERNATION_REBOOT:
646 kernel_restart(NULL);
647 break;
648 case HIBERNATION_PLATFORM:
649 hibernation_platform_enter();
650 /* Fall through */
651 case HIBERNATION_SHUTDOWN:
652 if (pm_power_off)
653 kernel_power_off();
654 break;
655 }
656 kernel_halt();
657 /*
658 * Valid image is on the disk, if we continue we risk serious data
659 * corruption after resume.
660 */
661 pr_crit("Power down manually\n");
662 while (1)
663 cpu_relax();
664}
665
666static int load_image_and_restore(void)
667{
668 int error;
669 unsigned int flags;
670
671 pm_pr_dbg("Loading hibernation image.\n");
672
673 lock_device_hotplug();
674 error = create_basic_memory_bitmaps();
675 if (error)
676 goto Unlock;
677
678 error = swsusp_read(&flags);
679 swsusp_close(FMODE_READ);
680 if (!error)
681 hibernation_restore(flags & SF_PLATFORM_MODE);
682
683 pr_err("Failed to load hibernation image, recovering.\n");
684 swsusp_free();
685 free_basic_memory_bitmaps();
686 Unlock:
687 unlock_device_hotplug();
688
689 return error;
690}
691
692/**
693 * hibernate - Carry out system hibernation, including saving the image.
694 */
695int hibernate(void)
696{
697 int error, nr_calls = 0;
698 bool snapshot_test = false;
699
700 if (!hibernation_available()) {
701 pm_pr_dbg("Hibernation not available.\n");
702 return -EPERM;
703 }
704
705 lock_system_sleep();
706 /* The snapshot device should not be opened while we're running */
707 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
708 error = -EBUSY;
709 goto Unlock;
710 }
711
712 pr_info("hibernation entry\n");
713 pm_prepare_console();
714 error = __pm_notifier_call_chain(PM_HIBERNATION_PREPARE, -1, &nr_calls);
715 if (error) {
716 nr_calls--;
717 goto Exit;
718 }
719
720 ksys_sync_helper();
721
722 error = freeze_processes();
723 if (error)
724 goto Exit;
725
726 lock_device_hotplug();
727 /* Allocate memory management structures */
728 error = create_basic_memory_bitmaps();
729 if (error)
730 goto Thaw;
731
732 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
733 if (error || freezer_test_done)
734 goto Free_bitmaps;
735
736 if (in_suspend) {
737 unsigned int flags = 0;
738
739 if (hibernation_mode == HIBERNATION_PLATFORM)
740 flags |= SF_PLATFORM_MODE;
741 if (nocompress)
742 flags |= SF_NOCOMPRESS_MODE;
743 else
744 flags |= SF_CRC32_MODE;
745
746 pm_pr_dbg("Writing image.\n");
747 error = swsusp_write(flags);
748 swsusp_free();
749 if (!error) {
750 if (hibernation_mode == HIBERNATION_TEST_RESUME)
751 snapshot_test = true;
752 else
753 power_down();
754 }
755 in_suspend = 0;
756 pm_restore_gfp_mask();
757 } else {
758 pm_pr_dbg("Image restored successfully.\n");
759 }
760
761 Free_bitmaps:
762 free_basic_memory_bitmaps();
763 Thaw:
764 unlock_device_hotplug();
765 if (snapshot_test) {
766 pm_pr_dbg("Checking hibernation image\n");
767 error = swsusp_check();
768 if (!error)
769 error = load_image_and_restore();
770 }
771 thaw_processes();
772
773 /* Don't bother checking whether freezer_test_done is true */
774 freezer_test_done = false;
775 Exit:
776 __pm_notifier_call_chain(PM_POST_HIBERNATION, nr_calls, NULL);
777 pm_restore_console();
778 atomic_inc(&snapshot_device_available);
779 Unlock:
780 unlock_system_sleep();
781 pr_info("hibernation exit\n");
782
783 return error;
784}
785
786
787/**
788 * software_resume - Resume from a saved hibernation image.
789 *
790 * This routine is called as a late initcall, when all devices have been
791 * discovered and initialized already.
792 *
793 * The image reading code is called to see if there is a hibernation image
794 * available for reading. If that is the case, devices are quiesced and the
795 * contents of memory is restored from the saved image.
796 *
797 * If this is successful, control reappears in the restored target kernel in
798 * hibernation_snapshot() which returns to hibernate(). Otherwise, the routine
799 * attempts to recover gracefully and make the kernel return to the normal mode
800 * of operation.
801 */
802static int software_resume(void)
803{
804 int error, nr_calls = 0;
805
806 /*
807 * If the user said "noresume".. bail out early.
808 */
809 if (noresume || !hibernation_available())
810 return 0;
811
812 /*
813 * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
814 * is configured into the kernel. Since the regular hibernate
815 * trigger path is via sysfs which takes a buffer mutex before
816 * calling hibernate functions (which take system_transition_mutex)
817 * this can cause lockdep to complain about a possible ABBA deadlock
818 * which cannot happen since we're in the boot code here and
819 * sysfs can't be invoked yet. Therefore, we use a subclass
820 * here to avoid lockdep complaining.
821 */
822 mutex_lock_nested(&system_transition_mutex, SINGLE_DEPTH_NESTING);
823
824 if (swsusp_resume_device)
825 goto Check_image;
826
827 if (!strlen(resume_file)) {
828 error = -ENOENT;
829 goto Unlock;
830 }
831
832 pm_pr_dbg("Checking hibernation image partition %s\n", resume_file);
833
834 if (resume_delay) {
835 pr_info("Waiting %dsec before reading resume device ...\n",
836 resume_delay);
837 ssleep(resume_delay);
838 }
839
840 /* Check if the device is there */
841 swsusp_resume_device = name_to_dev_t(resume_file);
842
843 /*
844 * name_to_dev_t is ineffective to verify parition if resume_file is in
845 * integer format. (e.g. major:minor)
846 */
847 if (isdigit(resume_file[0]) && resume_wait) {
848 int partno;
849 while (!get_gendisk(swsusp_resume_device, &partno))
850 msleep(10);
851 }
852
853 if (!swsusp_resume_device) {
854 /*
855 * Some device discovery might still be in progress; we need
856 * to wait for this to finish.
857 */
858 wait_for_device_probe();
859
860 if (resume_wait) {
861 while ((swsusp_resume_device = name_to_dev_t(resume_file)) == 0)
862 msleep(10);
863 async_synchronize_full();
864 }
865
866 swsusp_resume_device = name_to_dev_t(resume_file);
867 if (!swsusp_resume_device) {
868 error = -ENODEV;
869 goto Unlock;
870 }
871 }
872
873 Check_image:
874 pm_pr_dbg("Hibernation image partition %d:%d present\n",
875 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
876
877 pm_pr_dbg("Looking for hibernation image.\n");
878 error = swsusp_check();
879 if (error)
880 goto Unlock;
881
882 /* The snapshot device should not be opened while we're running */
883 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
884 error = -EBUSY;
885 swsusp_close(FMODE_READ);
886 goto Unlock;
887 }
888
889 pr_info("resume from hibernation\n");
890 pm_prepare_console();
891 error = __pm_notifier_call_chain(PM_RESTORE_PREPARE, -1, &nr_calls);
892 if (error) {
893 nr_calls--;
894 goto Close_Finish;
895 }
896
897 pm_pr_dbg("Preparing processes for restore.\n");
898 error = freeze_processes();
899 if (error)
900 goto Close_Finish;
901 error = load_image_and_restore();
902 thaw_processes();
903 Finish:
904 __pm_notifier_call_chain(PM_POST_RESTORE, nr_calls, NULL);
905 pm_restore_console();
906 pr_info("resume from hibernation failed (%d)\n", error);
907 atomic_inc(&snapshot_device_available);
908 /* For success case, the suspend path will release the lock */
909 Unlock:
910 mutex_unlock(&system_transition_mutex);
911 pm_pr_dbg("Hibernation image not present or could not be loaded.\n");
912 return error;
913 Close_Finish:
914 swsusp_close(FMODE_READ);
915 goto Finish;
916}
917
918late_initcall_sync(software_resume);
919
920
921static const char * const hibernation_modes[] = {
922 [HIBERNATION_PLATFORM] = "platform",
923 [HIBERNATION_SHUTDOWN] = "shutdown",
924 [HIBERNATION_REBOOT] = "reboot",
925#ifdef CONFIG_SUSPEND
926 [HIBERNATION_SUSPEND] = "suspend",
927#endif
928 [HIBERNATION_TEST_RESUME] = "test_resume",
929};
930
931/*
932 * /sys/power/disk - Control hibernation mode.
933 *
934 * Hibernation can be handled in several ways. There are a few different ways
935 * to put the system into the sleep state: using the platform driver (e.g. ACPI
936 * or other hibernation_ops), powering it off or rebooting it (for testing
937 * mostly).
938 *
939 * The sysfs file /sys/power/disk provides an interface for selecting the
940 * hibernation mode to use. Reading from this file causes the available modes
941 * to be printed. There are 3 modes that can be supported:
942 *
943 * 'platform'
944 * 'shutdown'
945 * 'reboot'
946 *
947 * If a platform hibernation driver is in use, 'platform' will be supported
948 * and will be used by default. Otherwise, 'shutdown' will be used by default.
949 * The selected option (i.e. the one corresponding to the current value of
950 * hibernation_mode) is enclosed by a square bracket.
951 *
952 * To select a given hibernation mode it is necessary to write the mode's
953 * string representation (as returned by reading from /sys/power/disk) back
954 * into /sys/power/disk.
955 */
956
957static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
958 char *buf)
959{
960 int i;
961 char *start = buf;
962
963 if (!hibernation_available())
964 return sprintf(buf, "[disabled]\n");
965
966 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
967 if (!hibernation_modes[i])
968 continue;
969 switch (i) {
970 case HIBERNATION_SHUTDOWN:
971 case HIBERNATION_REBOOT:
972#ifdef CONFIG_SUSPEND
973 case HIBERNATION_SUSPEND:
974#endif
975 case HIBERNATION_TEST_RESUME:
976 break;
977 case HIBERNATION_PLATFORM:
978 if (hibernation_ops)
979 break;
980 /* not a valid mode, continue with loop */
981 continue;
982 }
983 if (i == hibernation_mode)
984 buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
985 else
986 buf += sprintf(buf, "%s ", hibernation_modes[i]);
987 }
988 buf += sprintf(buf, "\n");
989 return buf-start;
990}
991
992static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
993 const char *buf, size_t n)
994{
995 int error = 0;
996 int i;
997 int len;
998 char *p;
999 int mode = HIBERNATION_INVALID;
1000
1001 if (!hibernation_available())
1002 return -EPERM;
1003
1004 p = memchr(buf, '\n', n);
1005 len = p ? p - buf : n;
1006
1007 lock_system_sleep();
1008 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
1009 if (len == strlen(hibernation_modes[i])
1010 && !strncmp(buf, hibernation_modes[i], len)) {
1011 mode = i;
1012 break;
1013 }
1014 }
1015 if (mode != HIBERNATION_INVALID) {
1016 switch (mode) {
1017 case HIBERNATION_SHUTDOWN:
1018 case HIBERNATION_REBOOT:
1019#ifdef CONFIG_SUSPEND
1020 case HIBERNATION_SUSPEND:
1021#endif
1022 case HIBERNATION_TEST_RESUME:
1023 hibernation_mode = mode;
1024 break;
1025 case HIBERNATION_PLATFORM:
1026 if (hibernation_ops)
1027 hibernation_mode = mode;
1028 else
1029 error = -EINVAL;
1030 }
1031 } else
1032 error = -EINVAL;
1033
1034 if (!error)
1035 pm_pr_dbg("Hibernation mode set to '%s'\n",
1036 hibernation_modes[mode]);
1037 unlock_system_sleep();
1038 return error ? error : n;
1039}
1040
1041power_attr(disk);
1042
1043static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
1044 char *buf)
1045{
1046 return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
1047 MINOR(swsusp_resume_device));
1048}
1049
1050static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
1051 const char *buf, size_t n)
1052{
1053 dev_t res;
1054 int len = n;
1055 char *name;
1056
1057 if (len && buf[len-1] == '\n')
1058 len--;
1059 name = kstrndup(buf, len, GFP_KERNEL);
1060 if (!name)
1061 return -ENOMEM;
1062
1063 res = name_to_dev_t(name);
1064 kfree(name);
1065 if (!res)
1066 return -EINVAL;
1067
1068 lock_system_sleep();
1069 swsusp_resume_device = res;
1070 unlock_system_sleep();
1071 pm_pr_dbg("Configured resume from disk to %u\n", swsusp_resume_device);
1072 noresume = 0;
1073 software_resume();
1074 return n;
1075}
1076
1077power_attr(resume);
1078
1079static ssize_t resume_offset_show(struct kobject *kobj,
1080 struct kobj_attribute *attr, char *buf)
1081{
1082 return sprintf(buf, "%llu\n", (unsigned long long)swsusp_resume_block);
1083}
1084
1085static ssize_t resume_offset_store(struct kobject *kobj,
1086 struct kobj_attribute *attr, const char *buf,
1087 size_t n)
1088{
1089 unsigned long long offset;
1090 int rc;
1091
1092 rc = kstrtoull(buf, 0, &offset);
1093 if (rc)
1094 return rc;
1095 swsusp_resume_block = offset;
1096
1097 return n;
1098}
1099
1100power_attr(resume_offset);
1101
1102static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
1103 char *buf)
1104{
1105 return sprintf(buf, "%lu\n", image_size);
1106}
1107
1108static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
1109 const char *buf, size_t n)
1110{
1111 unsigned long size;
1112
1113 if (sscanf(buf, "%lu", &size) == 1) {
1114 image_size = size;
1115 return n;
1116 }
1117
1118 return -EINVAL;
1119}
1120
1121power_attr(image_size);
1122
1123static ssize_t reserved_size_show(struct kobject *kobj,
1124 struct kobj_attribute *attr, char *buf)
1125{
1126 return sprintf(buf, "%lu\n", reserved_size);
1127}
1128
1129static ssize_t reserved_size_store(struct kobject *kobj,
1130 struct kobj_attribute *attr,
1131 const char *buf, size_t n)
1132{
1133 unsigned long size;
1134
1135 if (sscanf(buf, "%lu", &size) == 1) {
1136 reserved_size = size;
1137 return n;
1138 }
1139
1140 return -EINVAL;
1141}
1142
1143power_attr(reserved_size);
1144
1145static struct attribute * g[] = {
1146 &disk_attr.attr,
1147 &resume_offset_attr.attr,
1148 &resume_attr.attr,
1149 &image_size_attr.attr,
1150 &reserved_size_attr.attr,
1151 NULL,
1152};
1153
1154
1155static const struct attribute_group attr_group = {
1156 .attrs = g,
1157};
1158
1159
1160static int __init pm_disk_init(void)
1161{
1162 return sysfs_create_group(power_kobj, &attr_group);
1163}
1164
1165core_initcall(pm_disk_init);
1166
1167
1168static int __init resume_setup(char *str)
1169{
1170 if (noresume)
1171 return 1;
1172
1173 strncpy( resume_file, str, 255 );
1174 return 1;
1175}
1176
1177static int __init resume_offset_setup(char *str)
1178{
1179 unsigned long long offset;
1180
1181 if (noresume)
1182 return 1;
1183
1184 if (sscanf(str, "%llu", &offset) == 1)
1185 swsusp_resume_block = offset;
1186
1187 return 1;
1188}
1189
1190static int __init hibernate_setup(char *str)
1191{
1192 if (!strncmp(str, "noresume", 8)) {
1193 noresume = 1;
1194 } else if (!strncmp(str, "nocompress", 10)) {
1195 nocompress = 1;
1196 } else if (!strncmp(str, "no", 2)) {
1197 noresume = 1;
1198 nohibernate = 1;
1199 } else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)
1200 && !strncmp(str, "protect_image", 13)) {
1201 enable_restore_image_protection();
1202 }
1203 return 1;
1204}
1205
1206static int __init noresume_setup(char *str)
1207{
1208 noresume = 1;
1209 return 1;
1210}
1211
1212static int __init resumewait_setup(char *str)
1213{
1214 resume_wait = 1;
1215 return 1;
1216}
1217
1218static int __init resumedelay_setup(char *str)
1219{
1220 int rc = kstrtouint(str, 0, &resume_delay);
1221
1222 if (rc)
1223 return rc;
1224 return 1;
1225}
1226
1227static int __init nohibernate_setup(char *str)
1228{
1229 noresume = 1;
1230 nohibernate = 1;
1231 return 1;
1232}
1233
1234__setup("noresume", noresume_setup);
1235__setup("resume_offset=", resume_offset_setup);
1236__setup("resume=", resume_setup);
1237__setup("hibernate=", hibernate_setup);
1238__setup("resumewait", resumewait_setup);
1239__setup("resumedelay=", resumedelay_setup);
1240__setup("nohibernate", nohibernate_setup);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * kernel/power/hibernate.c - Hibernation (a.k.a suspend-to-disk) support.
4 *
5 * Copyright (c) 2003 Patrick Mochel
6 * Copyright (c) 2003 Open Source Development Lab
7 * Copyright (c) 2004 Pavel Machek <pavel@ucw.cz>
8 * Copyright (c) 2009 Rafael J. Wysocki, Novell Inc.
9 * Copyright (C) 2012 Bojan Smojver <bojan@rexursive.com>
10 */
11
12#define pr_fmt(fmt) "PM: hibernation: " fmt
13
14#include <linux/blkdev.h>
15#include <linux/export.h>
16#include <linux/suspend.h>
17#include <linux/reboot.h>
18#include <linux/string.h>
19#include <linux/device.h>
20#include <linux/async.h>
21#include <linux/delay.h>
22#include <linux/fs.h>
23#include <linux/mount.h>
24#include <linux/pm.h>
25#include <linux/nmi.h>
26#include <linux/console.h>
27#include <linux/cpu.h>
28#include <linux/freezer.h>
29#include <linux/gfp.h>
30#include <linux/syscore_ops.h>
31#include <linux/ctype.h>
32#include <linux/ktime.h>
33#include <linux/security.h>
34#include <linux/secretmem.h>
35#include <trace/events/power.h>
36
37#include "power.h"
38
39
40static int nocompress;
41static int noresume;
42static int nohibernate;
43static int resume_wait;
44static unsigned int resume_delay;
45static char resume_file[256] = CONFIG_PM_STD_PARTITION;
46dev_t swsusp_resume_device;
47sector_t swsusp_resume_block;
48__visible int in_suspend __nosavedata;
49
50static char hibernate_compressor[CRYPTO_MAX_ALG_NAME] = CONFIG_HIBERNATION_DEF_COMP;
51
52/*
53 * Compression/decompression algorithm to be used while saving/loading
54 * image to/from disk. This would later be used in 'kernel/power/swap.c'
55 * to allocate comp streams.
56 */
57char hib_comp_algo[CRYPTO_MAX_ALG_NAME];
58
59enum {
60 HIBERNATION_INVALID,
61 HIBERNATION_PLATFORM,
62 HIBERNATION_SHUTDOWN,
63 HIBERNATION_REBOOT,
64#ifdef CONFIG_SUSPEND
65 HIBERNATION_SUSPEND,
66#endif
67 HIBERNATION_TEST_RESUME,
68 /* keep last */
69 __HIBERNATION_AFTER_LAST
70};
71#define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
72#define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
73
74static int hibernation_mode = HIBERNATION_SHUTDOWN;
75
76bool freezer_test_done;
77
78static const struct platform_hibernation_ops *hibernation_ops;
79
80static atomic_t hibernate_atomic = ATOMIC_INIT(1);
81
82bool hibernate_acquire(void)
83{
84 return atomic_add_unless(&hibernate_atomic, -1, 0);
85}
86
87void hibernate_release(void)
88{
89 atomic_inc(&hibernate_atomic);
90}
91
92bool hibernation_available(void)
93{
94 return nohibernate == 0 &&
95 !security_locked_down(LOCKDOWN_HIBERNATION) &&
96 !secretmem_active() && !cxl_mem_active();
97}
98
99/**
100 * hibernation_set_ops - Set the global hibernate operations.
101 * @ops: Hibernation operations to use in subsequent hibernation transitions.
102 */
103void hibernation_set_ops(const struct platform_hibernation_ops *ops)
104{
105 unsigned int sleep_flags;
106
107 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
108 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
109 && ops->restore_cleanup && ops->leave)) {
110 WARN_ON(1);
111 return;
112 }
113
114 sleep_flags = lock_system_sleep();
115
116 hibernation_ops = ops;
117 if (ops)
118 hibernation_mode = HIBERNATION_PLATFORM;
119 else if (hibernation_mode == HIBERNATION_PLATFORM)
120 hibernation_mode = HIBERNATION_SHUTDOWN;
121
122 unlock_system_sleep(sleep_flags);
123}
124EXPORT_SYMBOL_GPL(hibernation_set_ops);
125
126static bool entering_platform_hibernation;
127
128bool system_entering_hibernation(void)
129{
130 return entering_platform_hibernation;
131}
132EXPORT_SYMBOL(system_entering_hibernation);
133
134#ifdef CONFIG_PM_DEBUG
135static void hibernation_debug_sleep(void)
136{
137 pr_info("debug: Waiting for 5 seconds.\n");
138 mdelay(5000);
139}
140
141static int hibernation_test(int level)
142{
143 if (pm_test_level == level) {
144 hibernation_debug_sleep();
145 return 1;
146 }
147 return 0;
148}
149#else /* !CONFIG_PM_DEBUG */
150static int hibernation_test(int level) { return 0; }
151#endif /* !CONFIG_PM_DEBUG */
152
153/**
154 * platform_begin - Call platform to start hibernation.
155 * @platform_mode: Whether or not to use the platform driver.
156 */
157static int platform_begin(int platform_mode)
158{
159 return (platform_mode && hibernation_ops) ?
160 hibernation_ops->begin(PMSG_FREEZE) : 0;
161}
162
163/**
164 * platform_end - Call platform to finish transition to the working state.
165 * @platform_mode: Whether or not to use the platform driver.
166 */
167static void platform_end(int platform_mode)
168{
169 if (platform_mode && hibernation_ops)
170 hibernation_ops->end();
171}
172
173/**
174 * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
175 * @platform_mode: Whether or not to use the platform driver.
176 *
177 * Use the platform driver to prepare the system for creating a hibernate image,
178 * if so configured, and return an error code if that fails.
179 */
180
181static int platform_pre_snapshot(int platform_mode)
182{
183 return (platform_mode && hibernation_ops) ?
184 hibernation_ops->pre_snapshot() : 0;
185}
186
187/**
188 * platform_leave - Call platform to prepare a transition to the working state.
189 * @platform_mode: Whether or not to use the platform driver.
190 *
191 * Use the platform driver prepare to prepare the machine for switching to the
192 * normal mode of operation.
193 *
194 * This routine is called on one CPU with interrupts disabled.
195 */
196static void platform_leave(int platform_mode)
197{
198 if (platform_mode && hibernation_ops)
199 hibernation_ops->leave();
200}
201
202/**
203 * platform_finish - Call platform to switch the system to the working state.
204 * @platform_mode: Whether or not to use the platform driver.
205 *
206 * Use the platform driver to switch the machine to the normal mode of
207 * operation.
208 *
209 * This routine must be called after platform_prepare().
210 */
211static void platform_finish(int platform_mode)
212{
213 if (platform_mode && hibernation_ops)
214 hibernation_ops->finish();
215}
216
217/**
218 * platform_pre_restore - Prepare for hibernate image restoration.
219 * @platform_mode: Whether or not to use the platform driver.
220 *
221 * Use the platform driver to prepare the system for resume from a hibernation
222 * image.
223 *
224 * If the restore fails after this function has been called,
225 * platform_restore_cleanup() must be called.
226 */
227static int platform_pre_restore(int platform_mode)
228{
229 return (platform_mode && hibernation_ops) ?
230 hibernation_ops->pre_restore() : 0;
231}
232
233/**
234 * platform_restore_cleanup - Switch to the working state after failing restore.
235 * @platform_mode: Whether or not to use the platform driver.
236 *
237 * Use the platform driver to switch the system to the normal mode of operation
238 * after a failing restore.
239 *
240 * If platform_pre_restore() has been called before the failing restore, this
241 * function must be called too, regardless of the result of
242 * platform_pre_restore().
243 */
244static void platform_restore_cleanup(int platform_mode)
245{
246 if (platform_mode && hibernation_ops)
247 hibernation_ops->restore_cleanup();
248}
249
250/**
251 * platform_recover - Recover from a failure to suspend devices.
252 * @platform_mode: Whether or not to use the platform driver.
253 */
254static void platform_recover(int platform_mode)
255{
256 if (platform_mode && hibernation_ops && hibernation_ops->recover)
257 hibernation_ops->recover();
258}
259
260/**
261 * swsusp_show_speed - Print time elapsed between two events during hibernation.
262 * @start: Starting event.
263 * @stop: Final event.
264 * @nr_pages: Number of memory pages processed between @start and @stop.
265 * @msg: Additional diagnostic message to print.
266 */
267void swsusp_show_speed(ktime_t start, ktime_t stop,
268 unsigned nr_pages, char *msg)
269{
270 ktime_t diff;
271 u64 elapsed_centisecs64;
272 unsigned int centisecs;
273 unsigned int k;
274 unsigned int kps;
275
276 diff = ktime_sub(stop, start);
277 elapsed_centisecs64 = ktime_divns(diff, 10*NSEC_PER_MSEC);
278 centisecs = elapsed_centisecs64;
279 if (centisecs == 0)
280 centisecs = 1; /* avoid div-by-zero */
281 k = nr_pages * (PAGE_SIZE / 1024);
282 kps = (k * 100) / centisecs;
283 pr_info("%s %u kbytes in %u.%02u seconds (%u.%02u MB/s)\n",
284 msg, k, centisecs / 100, centisecs % 100, kps / 1000,
285 (kps % 1000) / 10);
286}
287
288__weak int arch_resume_nosmt(void)
289{
290 return 0;
291}
292
293/**
294 * create_image - Create a hibernation image.
295 * @platform_mode: Whether or not to use the platform driver.
296 *
297 * Execute device drivers' "late" and "noirq" freeze callbacks, create a
298 * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
299 *
300 * Control reappears in this routine after the subsequent restore.
301 */
302static int create_image(int platform_mode)
303{
304 int error;
305
306 error = dpm_suspend_end(PMSG_FREEZE);
307 if (error) {
308 pr_err("Some devices failed to power down, aborting\n");
309 return error;
310 }
311
312 error = platform_pre_snapshot(platform_mode);
313 if (error || hibernation_test(TEST_PLATFORM))
314 goto Platform_finish;
315
316 error = pm_sleep_disable_secondary_cpus();
317 if (error || hibernation_test(TEST_CPUS))
318 goto Enable_cpus;
319
320 local_irq_disable();
321
322 system_state = SYSTEM_SUSPEND;
323
324 error = syscore_suspend();
325 if (error) {
326 pr_err("Some system devices failed to power down, aborting\n");
327 goto Enable_irqs;
328 }
329
330 if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
331 goto Power_up;
332
333 in_suspend = 1;
334 save_processor_state();
335 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true);
336 error = swsusp_arch_suspend();
337 /* Restore control flow magically appears here */
338 restore_processor_state();
339 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false);
340 if (error)
341 pr_err("Error %d creating image\n", error);
342
343 if (!in_suspend) {
344 events_check_enabled = false;
345 clear_or_poison_free_pages();
346 }
347
348 platform_leave(platform_mode);
349
350 Power_up:
351 syscore_resume();
352
353 Enable_irqs:
354 system_state = SYSTEM_RUNNING;
355 local_irq_enable();
356
357 Enable_cpus:
358 pm_sleep_enable_secondary_cpus();
359
360 /* Allow architectures to do nosmt-specific post-resume dances */
361 if (!in_suspend)
362 error = arch_resume_nosmt();
363
364 Platform_finish:
365 platform_finish(platform_mode);
366
367 dpm_resume_start(in_suspend ?
368 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
369
370 return error;
371}
372
373/**
374 * hibernation_snapshot - Quiesce devices and create a hibernation image.
375 * @platform_mode: If set, use platform driver to prepare for the transition.
376 *
377 * This routine must be called with system_transition_mutex held.
378 */
379int hibernation_snapshot(int platform_mode)
380{
381 pm_message_t msg;
382 int error;
383
384 pm_suspend_clear_flags();
385 error = platform_begin(platform_mode);
386 if (error)
387 goto Close;
388
389 /* Preallocate image memory before shutting down devices. */
390 error = hibernate_preallocate_memory();
391 if (error)
392 goto Close;
393
394 error = freeze_kernel_threads();
395 if (error)
396 goto Cleanup;
397
398 if (hibernation_test(TEST_FREEZER)) {
399
400 /*
401 * Indicate to the caller that we are returning due to a
402 * successful freezer test.
403 */
404 freezer_test_done = true;
405 goto Thaw;
406 }
407
408 error = dpm_prepare(PMSG_FREEZE);
409 if (error) {
410 dpm_complete(PMSG_RECOVER);
411 goto Thaw;
412 }
413
414 suspend_console();
415 pm_restrict_gfp_mask();
416
417 error = dpm_suspend(PMSG_FREEZE);
418
419 if (error || hibernation_test(TEST_DEVICES))
420 platform_recover(platform_mode);
421 else
422 error = create_image(platform_mode);
423
424 /*
425 * In the case that we call create_image() above, the control
426 * returns here (1) after the image has been created or the
427 * image creation has failed and (2) after a successful restore.
428 */
429
430 /* We may need to release the preallocated image pages here. */
431 if (error || !in_suspend)
432 swsusp_free();
433
434 msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
435 dpm_resume(msg);
436
437 if (error || !in_suspend)
438 pm_restore_gfp_mask();
439
440 resume_console();
441 dpm_complete(msg);
442
443 Close:
444 platform_end(platform_mode);
445 return error;
446
447 Thaw:
448 thaw_kernel_threads();
449 Cleanup:
450 swsusp_free();
451 goto Close;
452}
453
454int __weak hibernate_resume_nonboot_cpu_disable(void)
455{
456 return suspend_disable_secondary_cpus();
457}
458
459/**
460 * resume_target_kernel - Restore system state from a hibernation image.
461 * @platform_mode: Whether or not to use the platform driver.
462 *
463 * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
464 * contents of highmem that have not been restored yet from the image and run
465 * the low-level code that will restore the remaining contents of memory and
466 * switch to the just restored target kernel.
467 */
468static int resume_target_kernel(bool platform_mode)
469{
470 int error;
471
472 error = dpm_suspend_end(PMSG_QUIESCE);
473 if (error) {
474 pr_err("Some devices failed to power down, aborting resume\n");
475 return error;
476 }
477
478 error = platform_pre_restore(platform_mode);
479 if (error)
480 goto Cleanup;
481
482 cpuidle_pause();
483
484 error = hibernate_resume_nonboot_cpu_disable();
485 if (error)
486 goto Enable_cpus;
487
488 local_irq_disable();
489 system_state = SYSTEM_SUSPEND;
490
491 error = syscore_suspend();
492 if (error)
493 goto Enable_irqs;
494
495 save_processor_state();
496 error = restore_highmem();
497 if (!error) {
498 error = swsusp_arch_resume();
499 /*
500 * The code below is only ever reached in case of a failure.
501 * Otherwise, execution continues at the place where
502 * swsusp_arch_suspend() was called.
503 */
504 BUG_ON(!error);
505 /*
506 * This call to restore_highmem() reverts the changes made by
507 * the previous one.
508 */
509 restore_highmem();
510 }
511 /*
512 * The only reason why swsusp_arch_resume() can fail is memory being
513 * very tight, so we have to free it as soon as we can to avoid
514 * subsequent failures.
515 */
516 swsusp_free();
517 restore_processor_state();
518 touch_softlockup_watchdog();
519
520 syscore_resume();
521
522 Enable_irqs:
523 system_state = SYSTEM_RUNNING;
524 local_irq_enable();
525
526 Enable_cpus:
527 pm_sleep_enable_secondary_cpus();
528
529 Cleanup:
530 platform_restore_cleanup(platform_mode);
531
532 dpm_resume_start(PMSG_RECOVER);
533
534 return error;
535}
536
537/**
538 * hibernation_restore - Quiesce devices and restore from a hibernation image.
539 * @platform_mode: If set, use platform driver to prepare for the transition.
540 *
541 * This routine must be called with system_transition_mutex held. If it is
542 * successful, control reappears in the restored target kernel in
543 * hibernation_snapshot().
544 */
545int hibernation_restore(int platform_mode)
546{
547 int error;
548
549 pm_prepare_console();
550 suspend_console();
551 pm_restrict_gfp_mask();
552 error = dpm_suspend_start(PMSG_QUIESCE);
553 if (!error) {
554 error = resume_target_kernel(platform_mode);
555 /*
556 * The above should either succeed and jump to the new kernel,
557 * or return with an error. Otherwise things are just
558 * undefined, so let's be paranoid.
559 */
560 BUG_ON(!error);
561 }
562 dpm_resume_end(PMSG_RECOVER);
563 pm_restore_gfp_mask();
564 resume_console();
565 pm_restore_console();
566 return error;
567}
568
569/**
570 * hibernation_platform_enter - Power off the system using the platform driver.
571 */
572int hibernation_platform_enter(void)
573{
574 int error;
575
576 if (!hibernation_ops)
577 return -ENOSYS;
578
579 /*
580 * We have cancelled the power transition by running
581 * hibernation_ops->finish() before saving the image, so we should let
582 * the firmware know that we're going to enter the sleep state after all
583 */
584 error = hibernation_ops->begin(PMSG_HIBERNATE);
585 if (error)
586 goto Close;
587
588 entering_platform_hibernation = true;
589 suspend_console();
590 error = dpm_suspend_start(PMSG_HIBERNATE);
591 if (error) {
592 if (hibernation_ops->recover)
593 hibernation_ops->recover();
594 goto Resume_devices;
595 }
596
597 error = dpm_suspend_end(PMSG_HIBERNATE);
598 if (error)
599 goto Resume_devices;
600
601 error = hibernation_ops->prepare();
602 if (error)
603 goto Platform_finish;
604
605 error = pm_sleep_disable_secondary_cpus();
606 if (error)
607 goto Enable_cpus;
608
609 local_irq_disable();
610 system_state = SYSTEM_SUSPEND;
611 syscore_suspend();
612 if (pm_wakeup_pending()) {
613 error = -EAGAIN;
614 goto Power_up;
615 }
616
617 hibernation_ops->enter();
618 /* We should never get here */
619 while (1);
620
621 Power_up:
622 syscore_resume();
623 system_state = SYSTEM_RUNNING;
624 local_irq_enable();
625
626 Enable_cpus:
627 pm_sleep_enable_secondary_cpus();
628
629 Platform_finish:
630 hibernation_ops->finish();
631
632 dpm_resume_start(PMSG_RESTORE);
633
634 Resume_devices:
635 entering_platform_hibernation = false;
636 dpm_resume_end(PMSG_RESTORE);
637 resume_console();
638
639 Close:
640 hibernation_ops->end();
641
642 return error;
643}
644
645/**
646 * power_down - Shut the machine down for hibernation.
647 *
648 * Use the platform driver, if configured, to put the system into the sleep
649 * state corresponding to hibernation, or try to power it off or reboot,
650 * depending on the value of hibernation_mode.
651 */
652static void power_down(void)
653{
654 int error;
655
656#ifdef CONFIG_SUSPEND
657 if (hibernation_mode == HIBERNATION_SUSPEND) {
658 error = suspend_devices_and_enter(mem_sleep_current);
659 if (error) {
660 hibernation_mode = hibernation_ops ?
661 HIBERNATION_PLATFORM :
662 HIBERNATION_SHUTDOWN;
663 } else {
664 /* Restore swap signature. */
665 error = swsusp_unmark();
666 if (error)
667 pr_err("Swap will be unusable! Try swapon -a.\n");
668
669 return;
670 }
671 }
672#endif
673
674 switch (hibernation_mode) {
675 case HIBERNATION_REBOOT:
676 kernel_restart(NULL);
677 break;
678 case HIBERNATION_PLATFORM:
679 error = hibernation_platform_enter();
680 if (error == -EAGAIN || error == -EBUSY) {
681 swsusp_unmark();
682 events_check_enabled = false;
683 pr_info("Wakeup event detected during hibernation, rolling back.\n");
684 return;
685 }
686 fallthrough;
687 case HIBERNATION_SHUTDOWN:
688 if (kernel_can_power_off())
689 kernel_power_off();
690 break;
691 }
692 kernel_halt();
693 /*
694 * Valid image is on the disk, if we continue we risk serious data
695 * corruption after resume.
696 */
697 pr_crit("Power down manually\n");
698 while (1)
699 cpu_relax();
700}
701
702static int load_image_and_restore(void)
703{
704 int error;
705 unsigned int flags;
706
707 pm_pr_dbg("Loading hibernation image.\n");
708
709 lock_device_hotplug();
710 error = create_basic_memory_bitmaps();
711 if (error) {
712 swsusp_close();
713 goto Unlock;
714 }
715
716 error = swsusp_read(&flags);
717 swsusp_close();
718 if (!error)
719 error = hibernation_restore(flags & SF_PLATFORM_MODE);
720
721 pr_err("Failed to load image, recovering.\n");
722 swsusp_free();
723 free_basic_memory_bitmaps();
724 Unlock:
725 unlock_device_hotplug();
726
727 return error;
728}
729
730#define COMPRESSION_ALGO_LZO "lzo"
731#define COMPRESSION_ALGO_LZ4 "lz4"
732
733/**
734 * hibernate - Carry out system hibernation, including saving the image.
735 */
736int hibernate(void)
737{
738 bool snapshot_test = false;
739 unsigned int sleep_flags;
740 int error;
741
742 if (!hibernation_available()) {
743 pm_pr_dbg("Hibernation not available.\n");
744 return -EPERM;
745 }
746
747 /*
748 * Query for the compression algorithm support if compression is enabled.
749 */
750 if (!nocompress) {
751 strscpy(hib_comp_algo, hibernate_compressor, sizeof(hib_comp_algo));
752 if (crypto_has_comp(hib_comp_algo, 0, 0) != 1) {
753 pr_err("%s compression is not available\n", hib_comp_algo);
754 return -EOPNOTSUPP;
755 }
756 }
757
758 sleep_flags = lock_system_sleep();
759 /* The snapshot device should not be opened while we're running */
760 if (!hibernate_acquire()) {
761 error = -EBUSY;
762 goto Unlock;
763 }
764
765 pr_info("hibernation entry\n");
766 pm_prepare_console();
767 error = pm_notifier_call_chain_robust(PM_HIBERNATION_PREPARE, PM_POST_HIBERNATION);
768 if (error)
769 goto Restore;
770
771 ksys_sync_helper();
772
773 error = freeze_processes();
774 if (error)
775 goto Exit;
776
777 lock_device_hotplug();
778 /* Allocate memory management structures */
779 error = create_basic_memory_bitmaps();
780 if (error)
781 goto Thaw;
782
783 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
784 if (error || freezer_test_done)
785 goto Free_bitmaps;
786
787 if (in_suspend) {
788 unsigned int flags = 0;
789
790 if (hibernation_mode == HIBERNATION_PLATFORM)
791 flags |= SF_PLATFORM_MODE;
792 if (nocompress) {
793 flags |= SF_NOCOMPRESS_MODE;
794 } else {
795 flags |= SF_CRC32_MODE;
796
797 /*
798 * By default, LZO compression is enabled. Use SF_COMPRESSION_ALG_LZ4
799 * to override this behaviour and use LZ4.
800 *
801 * Refer kernel/power/power.h for more details
802 */
803
804 if (!strcmp(hib_comp_algo, COMPRESSION_ALGO_LZ4))
805 flags |= SF_COMPRESSION_ALG_LZ4;
806 else
807 flags |= SF_COMPRESSION_ALG_LZO;
808 }
809
810 pm_pr_dbg("Writing hibernation image.\n");
811 error = swsusp_write(flags);
812 swsusp_free();
813 if (!error) {
814 if (hibernation_mode == HIBERNATION_TEST_RESUME)
815 snapshot_test = true;
816 else
817 power_down();
818 }
819 in_suspend = 0;
820 pm_restore_gfp_mask();
821 } else {
822 pm_pr_dbg("Hibernation image restored successfully.\n");
823 }
824
825 Free_bitmaps:
826 free_basic_memory_bitmaps();
827 Thaw:
828 unlock_device_hotplug();
829 if (snapshot_test) {
830 pm_pr_dbg("Checking hibernation image\n");
831 error = swsusp_check(false);
832 if (!error)
833 error = load_image_and_restore();
834 }
835 thaw_processes();
836
837 /* Don't bother checking whether freezer_test_done is true */
838 freezer_test_done = false;
839 Exit:
840 pm_notifier_call_chain(PM_POST_HIBERNATION);
841 Restore:
842 pm_restore_console();
843 hibernate_release();
844 Unlock:
845 unlock_system_sleep(sleep_flags);
846 pr_info("hibernation exit\n");
847
848 return error;
849}
850
851/**
852 * hibernate_quiet_exec - Execute a function with all devices frozen.
853 * @func: Function to execute.
854 * @data: Data pointer to pass to @func.
855 *
856 * Return the @func return value or an error code if it cannot be executed.
857 */
858int hibernate_quiet_exec(int (*func)(void *data), void *data)
859{
860 unsigned int sleep_flags;
861 int error;
862
863 sleep_flags = lock_system_sleep();
864
865 if (!hibernate_acquire()) {
866 error = -EBUSY;
867 goto unlock;
868 }
869
870 pm_prepare_console();
871
872 error = pm_notifier_call_chain_robust(PM_HIBERNATION_PREPARE, PM_POST_HIBERNATION);
873 if (error)
874 goto restore;
875
876 error = freeze_processes();
877 if (error)
878 goto exit;
879
880 lock_device_hotplug();
881
882 pm_suspend_clear_flags();
883
884 error = platform_begin(true);
885 if (error)
886 goto thaw;
887
888 error = freeze_kernel_threads();
889 if (error)
890 goto thaw;
891
892 error = dpm_prepare(PMSG_FREEZE);
893 if (error)
894 goto dpm_complete;
895
896 suspend_console();
897
898 error = dpm_suspend(PMSG_FREEZE);
899 if (error)
900 goto dpm_resume;
901
902 error = dpm_suspend_end(PMSG_FREEZE);
903 if (error)
904 goto dpm_resume;
905
906 error = platform_pre_snapshot(true);
907 if (error)
908 goto skip;
909
910 error = func(data);
911
912skip:
913 platform_finish(true);
914
915 dpm_resume_start(PMSG_THAW);
916
917dpm_resume:
918 dpm_resume(PMSG_THAW);
919
920 resume_console();
921
922dpm_complete:
923 dpm_complete(PMSG_THAW);
924
925 thaw_kernel_threads();
926
927thaw:
928 platform_end(true);
929
930 unlock_device_hotplug();
931
932 thaw_processes();
933
934exit:
935 pm_notifier_call_chain(PM_POST_HIBERNATION);
936
937restore:
938 pm_restore_console();
939
940 hibernate_release();
941
942unlock:
943 unlock_system_sleep(sleep_flags);
944
945 return error;
946}
947EXPORT_SYMBOL_GPL(hibernate_quiet_exec);
948
949static int __init find_resume_device(void)
950{
951 if (!strlen(resume_file))
952 return -ENOENT;
953
954 pm_pr_dbg("Checking hibernation image partition %s\n", resume_file);
955
956 if (resume_delay) {
957 pr_info("Waiting %dsec before reading resume device ...\n",
958 resume_delay);
959 ssleep(resume_delay);
960 }
961
962 /* Check if the device is there */
963 if (!early_lookup_bdev(resume_file, &swsusp_resume_device))
964 return 0;
965
966 /*
967 * Some device discovery might still be in progress; we need to wait for
968 * this to finish.
969 */
970 wait_for_device_probe();
971 if (resume_wait) {
972 while (early_lookup_bdev(resume_file, &swsusp_resume_device))
973 msleep(10);
974 async_synchronize_full();
975 }
976
977 return early_lookup_bdev(resume_file, &swsusp_resume_device);
978}
979
980static int software_resume(void)
981{
982 int error;
983
984 pm_pr_dbg("Hibernation image partition %d:%d present\n",
985 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
986
987 pm_pr_dbg("Looking for hibernation image.\n");
988
989 mutex_lock(&system_transition_mutex);
990 error = swsusp_check(true);
991 if (error)
992 goto Unlock;
993
994 /*
995 * Check if the hibernation image is compressed. If so, query for
996 * the algorithm support.
997 */
998 if (!(swsusp_header_flags & SF_NOCOMPRESS_MODE)) {
999 if (swsusp_header_flags & SF_COMPRESSION_ALG_LZ4)
1000 strscpy(hib_comp_algo, COMPRESSION_ALGO_LZ4, sizeof(hib_comp_algo));
1001 else
1002 strscpy(hib_comp_algo, COMPRESSION_ALGO_LZO, sizeof(hib_comp_algo));
1003 if (crypto_has_comp(hib_comp_algo, 0, 0) != 1) {
1004 pr_err("%s compression is not available\n", hib_comp_algo);
1005 error = -EOPNOTSUPP;
1006 goto Unlock;
1007 }
1008 }
1009
1010 /* The snapshot device should not be opened while we're running */
1011 if (!hibernate_acquire()) {
1012 error = -EBUSY;
1013 swsusp_close();
1014 goto Unlock;
1015 }
1016
1017 pr_info("resume from hibernation\n");
1018 pm_prepare_console();
1019 error = pm_notifier_call_chain_robust(PM_RESTORE_PREPARE, PM_POST_RESTORE);
1020 if (error)
1021 goto Restore;
1022
1023 pm_pr_dbg("Preparing processes for hibernation restore.\n");
1024 error = freeze_processes();
1025 if (error)
1026 goto Close_Finish;
1027
1028 error = freeze_kernel_threads();
1029 if (error) {
1030 thaw_processes();
1031 goto Close_Finish;
1032 }
1033
1034 error = load_image_and_restore();
1035 thaw_processes();
1036 Finish:
1037 pm_notifier_call_chain(PM_POST_RESTORE);
1038 Restore:
1039 pm_restore_console();
1040 pr_info("resume failed (%d)\n", error);
1041 hibernate_release();
1042 /* For success case, the suspend path will release the lock */
1043 Unlock:
1044 mutex_unlock(&system_transition_mutex);
1045 pm_pr_dbg("Hibernation image not present or could not be loaded.\n");
1046 return error;
1047 Close_Finish:
1048 swsusp_close();
1049 goto Finish;
1050}
1051
1052/**
1053 * software_resume_initcall - Resume from a saved hibernation image.
1054 *
1055 * This routine is called as a late initcall, when all devices have been
1056 * discovered and initialized already.
1057 *
1058 * The image reading code is called to see if there is a hibernation image
1059 * available for reading. If that is the case, devices are quiesced and the
1060 * contents of memory is restored from the saved image.
1061 *
1062 * If this is successful, control reappears in the restored target kernel in
1063 * hibernation_snapshot() which returns to hibernate(). Otherwise, the routine
1064 * attempts to recover gracefully and make the kernel return to the normal mode
1065 * of operation.
1066 */
1067static int __init software_resume_initcall(void)
1068{
1069 /*
1070 * If the user said "noresume".. bail out early.
1071 */
1072 if (noresume || !hibernation_available())
1073 return 0;
1074
1075 if (!swsusp_resume_device) {
1076 int error = find_resume_device();
1077
1078 if (error)
1079 return error;
1080 }
1081
1082 return software_resume();
1083}
1084late_initcall_sync(software_resume_initcall);
1085
1086
1087static const char * const hibernation_modes[] = {
1088 [HIBERNATION_PLATFORM] = "platform",
1089 [HIBERNATION_SHUTDOWN] = "shutdown",
1090 [HIBERNATION_REBOOT] = "reboot",
1091#ifdef CONFIG_SUSPEND
1092 [HIBERNATION_SUSPEND] = "suspend",
1093#endif
1094 [HIBERNATION_TEST_RESUME] = "test_resume",
1095};
1096
1097/*
1098 * /sys/power/disk - Control hibernation mode.
1099 *
1100 * Hibernation can be handled in several ways. There are a few different ways
1101 * to put the system into the sleep state: using the platform driver (e.g. ACPI
1102 * or other hibernation_ops), powering it off or rebooting it (for testing
1103 * mostly).
1104 *
1105 * The sysfs file /sys/power/disk provides an interface for selecting the
1106 * hibernation mode to use. Reading from this file causes the available modes
1107 * to be printed. There are 3 modes that can be supported:
1108 *
1109 * 'platform'
1110 * 'shutdown'
1111 * 'reboot'
1112 *
1113 * If a platform hibernation driver is in use, 'platform' will be supported
1114 * and will be used by default. Otherwise, 'shutdown' will be used by default.
1115 * The selected option (i.e. the one corresponding to the current value of
1116 * hibernation_mode) is enclosed by a square bracket.
1117 *
1118 * To select a given hibernation mode it is necessary to write the mode's
1119 * string representation (as returned by reading from /sys/power/disk) back
1120 * into /sys/power/disk.
1121 */
1122
1123static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
1124 char *buf)
1125{
1126 int i;
1127 char *start = buf;
1128
1129 if (!hibernation_available())
1130 return sprintf(buf, "[disabled]\n");
1131
1132 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
1133 if (!hibernation_modes[i])
1134 continue;
1135 switch (i) {
1136 case HIBERNATION_SHUTDOWN:
1137 case HIBERNATION_REBOOT:
1138#ifdef CONFIG_SUSPEND
1139 case HIBERNATION_SUSPEND:
1140#endif
1141 case HIBERNATION_TEST_RESUME:
1142 break;
1143 case HIBERNATION_PLATFORM:
1144 if (hibernation_ops)
1145 break;
1146 /* not a valid mode, continue with loop */
1147 continue;
1148 }
1149 if (i == hibernation_mode)
1150 buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
1151 else
1152 buf += sprintf(buf, "%s ", hibernation_modes[i]);
1153 }
1154 buf += sprintf(buf, "\n");
1155 return buf-start;
1156}
1157
1158static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
1159 const char *buf, size_t n)
1160{
1161 int mode = HIBERNATION_INVALID;
1162 unsigned int sleep_flags;
1163 int error = 0;
1164 int len;
1165 char *p;
1166 int i;
1167
1168 if (!hibernation_available())
1169 return -EPERM;
1170
1171 p = memchr(buf, '\n', n);
1172 len = p ? p - buf : n;
1173
1174 sleep_flags = lock_system_sleep();
1175 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
1176 if (len == strlen(hibernation_modes[i])
1177 && !strncmp(buf, hibernation_modes[i], len)) {
1178 mode = i;
1179 break;
1180 }
1181 }
1182 if (mode != HIBERNATION_INVALID) {
1183 switch (mode) {
1184 case HIBERNATION_SHUTDOWN:
1185 case HIBERNATION_REBOOT:
1186#ifdef CONFIG_SUSPEND
1187 case HIBERNATION_SUSPEND:
1188#endif
1189 case HIBERNATION_TEST_RESUME:
1190 hibernation_mode = mode;
1191 break;
1192 case HIBERNATION_PLATFORM:
1193 if (hibernation_ops)
1194 hibernation_mode = mode;
1195 else
1196 error = -EINVAL;
1197 }
1198 } else
1199 error = -EINVAL;
1200
1201 if (!error)
1202 pm_pr_dbg("Hibernation mode set to '%s'\n",
1203 hibernation_modes[mode]);
1204 unlock_system_sleep(sleep_flags);
1205 return error ? error : n;
1206}
1207
1208power_attr(disk);
1209
1210static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
1211 char *buf)
1212{
1213 return sprintf(buf, "%d:%d\n", MAJOR(swsusp_resume_device),
1214 MINOR(swsusp_resume_device));
1215}
1216
1217static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
1218 const char *buf, size_t n)
1219{
1220 unsigned int sleep_flags;
1221 int len = n;
1222 char *name;
1223 dev_t dev;
1224 int error;
1225
1226 if (!hibernation_available())
1227 return n;
1228
1229 if (len && buf[len-1] == '\n')
1230 len--;
1231 name = kstrndup(buf, len, GFP_KERNEL);
1232 if (!name)
1233 return -ENOMEM;
1234
1235 error = lookup_bdev(name, &dev);
1236 if (error) {
1237 unsigned maj, min, offset;
1238 char *p, dummy;
1239
1240 error = 0;
1241 if (sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2 ||
1242 sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset,
1243 &dummy) == 3) {
1244 dev = MKDEV(maj, min);
1245 if (maj != MAJOR(dev) || min != MINOR(dev))
1246 error = -EINVAL;
1247 } else {
1248 dev = new_decode_dev(simple_strtoul(name, &p, 16));
1249 if (*p)
1250 error = -EINVAL;
1251 }
1252 }
1253 kfree(name);
1254 if (error)
1255 return error;
1256
1257 sleep_flags = lock_system_sleep();
1258 swsusp_resume_device = dev;
1259 unlock_system_sleep(sleep_flags);
1260
1261 pm_pr_dbg("Configured hibernation resume from disk to %u\n",
1262 swsusp_resume_device);
1263 noresume = 0;
1264 software_resume();
1265 return n;
1266}
1267
1268power_attr(resume);
1269
1270static ssize_t resume_offset_show(struct kobject *kobj,
1271 struct kobj_attribute *attr, char *buf)
1272{
1273 return sprintf(buf, "%llu\n", (unsigned long long)swsusp_resume_block);
1274}
1275
1276static ssize_t resume_offset_store(struct kobject *kobj,
1277 struct kobj_attribute *attr, const char *buf,
1278 size_t n)
1279{
1280 unsigned long long offset;
1281 int rc;
1282
1283 rc = kstrtoull(buf, 0, &offset);
1284 if (rc)
1285 return rc;
1286 swsusp_resume_block = offset;
1287
1288 return n;
1289}
1290
1291power_attr(resume_offset);
1292
1293static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
1294 char *buf)
1295{
1296 return sprintf(buf, "%lu\n", image_size);
1297}
1298
1299static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
1300 const char *buf, size_t n)
1301{
1302 unsigned long size;
1303
1304 if (sscanf(buf, "%lu", &size) == 1) {
1305 image_size = size;
1306 return n;
1307 }
1308
1309 return -EINVAL;
1310}
1311
1312power_attr(image_size);
1313
1314static ssize_t reserved_size_show(struct kobject *kobj,
1315 struct kobj_attribute *attr, char *buf)
1316{
1317 return sprintf(buf, "%lu\n", reserved_size);
1318}
1319
1320static ssize_t reserved_size_store(struct kobject *kobj,
1321 struct kobj_attribute *attr,
1322 const char *buf, size_t n)
1323{
1324 unsigned long size;
1325
1326 if (sscanf(buf, "%lu", &size) == 1) {
1327 reserved_size = size;
1328 return n;
1329 }
1330
1331 return -EINVAL;
1332}
1333
1334power_attr(reserved_size);
1335
1336static struct attribute *g[] = {
1337 &disk_attr.attr,
1338 &resume_offset_attr.attr,
1339 &resume_attr.attr,
1340 &image_size_attr.attr,
1341 &reserved_size_attr.attr,
1342 NULL,
1343};
1344
1345
1346static const struct attribute_group attr_group = {
1347 .attrs = g,
1348};
1349
1350
1351static int __init pm_disk_init(void)
1352{
1353 return sysfs_create_group(power_kobj, &attr_group);
1354}
1355
1356core_initcall(pm_disk_init);
1357
1358
1359static int __init resume_setup(char *str)
1360{
1361 if (noresume)
1362 return 1;
1363
1364 strncpy(resume_file, str, 255);
1365 return 1;
1366}
1367
1368static int __init resume_offset_setup(char *str)
1369{
1370 unsigned long long offset;
1371
1372 if (noresume)
1373 return 1;
1374
1375 if (sscanf(str, "%llu", &offset) == 1)
1376 swsusp_resume_block = offset;
1377
1378 return 1;
1379}
1380
1381static int __init hibernate_setup(char *str)
1382{
1383 if (!strncmp(str, "noresume", 8)) {
1384 noresume = 1;
1385 } else if (!strncmp(str, "nocompress", 10)) {
1386 nocompress = 1;
1387 } else if (!strncmp(str, "no", 2)) {
1388 noresume = 1;
1389 nohibernate = 1;
1390 } else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)
1391 && !strncmp(str, "protect_image", 13)) {
1392 enable_restore_image_protection();
1393 }
1394 return 1;
1395}
1396
1397static int __init noresume_setup(char *str)
1398{
1399 noresume = 1;
1400 return 1;
1401}
1402
1403static int __init resumewait_setup(char *str)
1404{
1405 resume_wait = 1;
1406 return 1;
1407}
1408
1409static int __init resumedelay_setup(char *str)
1410{
1411 int rc = kstrtouint(str, 0, &resume_delay);
1412
1413 if (rc)
1414 pr_warn("resumedelay: bad option string '%s'\n", str);
1415 return 1;
1416}
1417
1418static int __init nohibernate_setup(char *str)
1419{
1420 noresume = 1;
1421 nohibernate = 1;
1422 return 1;
1423}
1424
1425static const char * const comp_alg_enabled[] = {
1426#if IS_ENABLED(CONFIG_CRYPTO_LZO)
1427 COMPRESSION_ALGO_LZO,
1428#endif
1429#if IS_ENABLED(CONFIG_CRYPTO_LZ4)
1430 COMPRESSION_ALGO_LZ4,
1431#endif
1432};
1433
1434static int hibernate_compressor_param_set(const char *compressor,
1435 const struct kernel_param *kp)
1436{
1437 unsigned int sleep_flags;
1438 int index, ret;
1439
1440 sleep_flags = lock_system_sleep();
1441
1442 index = sysfs_match_string(comp_alg_enabled, compressor);
1443 if (index >= 0) {
1444 ret = param_set_copystring(comp_alg_enabled[index], kp);
1445 if (!ret)
1446 strscpy(hib_comp_algo, comp_alg_enabled[index],
1447 sizeof(hib_comp_algo));
1448 } else {
1449 ret = index;
1450 }
1451
1452 unlock_system_sleep(sleep_flags);
1453
1454 if (ret)
1455 pr_debug("Cannot set specified compressor %s\n",
1456 compressor);
1457
1458 return ret;
1459}
1460
1461static const struct kernel_param_ops hibernate_compressor_param_ops = {
1462 .set = hibernate_compressor_param_set,
1463 .get = param_get_string,
1464};
1465
1466static struct kparam_string hibernate_compressor_param_string = {
1467 .maxlen = sizeof(hibernate_compressor),
1468 .string = hibernate_compressor,
1469};
1470
1471module_param_cb(compressor, &hibernate_compressor_param_ops,
1472 &hibernate_compressor_param_string, 0644);
1473MODULE_PARM_DESC(compressor,
1474 "Compression algorithm to be used with hibernation");
1475
1476__setup("noresume", noresume_setup);
1477__setup("resume_offset=", resume_offset_setup);
1478__setup("resume=", resume_setup);
1479__setup("hibernate=", hibernate_setup);
1480__setup("resumewait", resumewait_setup);
1481__setup("resumedelay=", resumedelay_setup);
1482__setup("nohibernate", nohibernate_setup);