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1/*
2 * kernel/power/hibernate.c - Hibernation (a.k.a suspend-to-disk) support.
3 *
4 * Copyright (c) 2003 Patrick Mochel
5 * Copyright (c) 2003 Open Source Development Lab
6 * Copyright (c) 2004 Pavel Machek <pavel@ucw.cz>
7 * Copyright (c) 2009 Rafael J. Wysocki, Novell Inc.
8 * Copyright (C) 2012 Bojan Smojver <bojan@rexursive.com>
9 *
10 * This file is released under the GPLv2.
11 */
12
13#define pr_fmt(fmt) "PM: " fmt
14
15#include <linux/export.h>
16#include <linux/suspend.h>
17#include <linux/syscalls.h>
18#include <linux/reboot.h>
19#include <linux/string.h>
20#include <linux/device.h>
21#include <linux/async.h>
22#include <linux/delay.h>
23#include <linux/fs.h>
24#include <linux/mount.h>
25#include <linux/pm.h>
26#include <linux/nmi.h>
27#include <linux/console.h>
28#include <linux/cpu.h>
29#include <linux/freezer.h>
30#include <linux/gfp.h>
31#include <linux/syscore_ops.h>
32#include <linux/ctype.h>
33#include <linux/genhd.h>
34#include <linux/ktime.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
71bool hibernation_available(void)
72{
73 return (nohibernate == 0);
74}
75
76/**
77 * hibernation_set_ops - Set the global hibernate operations.
78 * @ops: Hibernation operations to use in subsequent hibernation transitions.
79 */
80void hibernation_set_ops(const struct platform_hibernation_ops *ops)
81{
82 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
83 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
84 && ops->restore_cleanup && ops->leave)) {
85 WARN_ON(1);
86 return;
87 }
88 lock_system_sleep();
89 hibernation_ops = ops;
90 if (ops)
91 hibernation_mode = HIBERNATION_PLATFORM;
92 else if (hibernation_mode == HIBERNATION_PLATFORM)
93 hibernation_mode = HIBERNATION_SHUTDOWN;
94
95 unlock_system_sleep();
96}
97EXPORT_SYMBOL_GPL(hibernation_set_ops);
98
99static bool entering_platform_hibernation;
100
101bool system_entering_hibernation(void)
102{
103 return entering_platform_hibernation;
104}
105EXPORT_SYMBOL(system_entering_hibernation);
106
107#ifdef CONFIG_PM_DEBUG
108static void hibernation_debug_sleep(void)
109{
110 pr_info("hibernation debug: Waiting for 5 seconds.\n");
111 mdelay(5000);
112}
113
114static int hibernation_test(int level)
115{
116 if (pm_test_level == level) {
117 hibernation_debug_sleep();
118 return 1;
119 }
120 return 0;
121}
122#else /* !CONFIG_PM_DEBUG */
123static int hibernation_test(int level) { return 0; }
124#endif /* !CONFIG_PM_DEBUG */
125
126/**
127 * platform_begin - Call platform to start hibernation.
128 * @platform_mode: Whether or not to use the platform driver.
129 */
130static int platform_begin(int platform_mode)
131{
132 return (platform_mode && hibernation_ops) ?
133 hibernation_ops->begin() : 0;
134}
135
136/**
137 * platform_end - Call platform to finish transition to the working state.
138 * @platform_mode: Whether or not to use the platform driver.
139 */
140static void platform_end(int platform_mode)
141{
142 if (platform_mode && hibernation_ops)
143 hibernation_ops->end();
144}
145
146/**
147 * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
148 * @platform_mode: Whether or not to use the platform driver.
149 *
150 * Use the platform driver to prepare the system for creating a hibernate image,
151 * if so configured, and return an error code if that fails.
152 */
153
154static int platform_pre_snapshot(int platform_mode)
155{
156 return (platform_mode && hibernation_ops) ?
157 hibernation_ops->pre_snapshot() : 0;
158}
159
160/**
161 * platform_leave - Call platform to prepare a transition to the working state.
162 * @platform_mode: Whether or not to use the platform driver.
163 *
164 * Use the platform driver prepare to prepare the machine for switching to the
165 * normal mode of operation.
166 *
167 * This routine is called on one CPU with interrupts disabled.
168 */
169static void platform_leave(int platform_mode)
170{
171 if (platform_mode && hibernation_ops)
172 hibernation_ops->leave();
173}
174
175/**
176 * platform_finish - Call platform to switch the system to the working state.
177 * @platform_mode: Whether or not to use the platform driver.
178 *
179 * Use the platform driver to switch the machine to the normal mode of
180 * operation.
181 *
182 * This routine must be called after platform_prepare().
183 */
184static void platform_finish(int platform_mode)
185{
186 if (platform_mode && hibernation_ops)
187 hibernation_ops->finish();
188}
189
190/**
191 * platform_pre_restore - Prepare for hibernate image restoration.
192 * @platform_mode: Whether or not to use the platform driver.
193 *
194 * Use the platform driver to prepare the system for resume from a hibernation
195 * image.
196 *
197 * If the restore fails after this function has been called,
198 * platform_restore_cleanup() must be called.
199 */
200static int platform_pre_restore(int platform_mode)
201{
202 return (platform_mode && hibernation_ops) ?
203 hibernation_ops->pre_restore() : 0;
204}
205
206/**
207 * platform_restore_cleanup - Switch to the working state after failing restore.
208 * @platform_mode: Whether or not to use the platform driver.
209 *
210 * Use the platform driver to switch the system to the normal mode of operation
211 * after a failing restore.
212 *
213 * If platform_pre_restore() has been called before the failing restore, this
214 * function must be called too, regardless of the result of
215 * platform_pre_restore().
216 */
217static void platform_restore_cleanup(int platform_mode)
218{
219 if (platform_mode && hibernation_ops)
220 hibernation_ops->restore_cleanup();
221}
222
223/**
224 * platform_recover - Recover from a failure to suspend devices.
225 * @platform_mode: Whether or not to use the platform driver.
226 */
227static void platform_recover(int platform_mode)
228{
229 if (platform_mode && hibernation_ops && hibernation_ops->recover)
230 hibernation_ops->recover();
231}
232
233/**
234 * swsusp_show_speed - Print time elapsed between two events during hibernation.
235 * @start: Starting event.
236 * @stop: Final event.
237 * @nr_pages: Number of memory pages processed between @start and @stop.
238 * @msg: Additional diagnostic message to print.
239 */
240void swsusp_show_speed(ktime_t start, ktime_t stop,
241 unsigned nr_pages, char *msg)
242{
243 ktime_t diff;
244 u64 elapsed_centisecs64;
245 unsigned int centisecs;
246 unsigned int k;
247 unsigned int kps;
248
249 diff = ktime_sub(stop, start);
250 elapsed_centisecs64 = ktime_divns(diff, 10*NSEC_PER_MSEC);
251 centisecs = elapsed_centisecs64;
252 if (centisecs == 0)
253 centisecs = 1; /* avoid div-by-zero */
254 k = nr_pages * (PAGE_SIZE / 1024);
255 kps = (k * 100) / centisecs;
256 pr_info("%s %u kbytes in %u.%02u seconds (%u.%02u MB/s)\n",
257 msg, k, centisecs / 100, centisecs % 100, kps / 1000,
258 (kps % 1000) / 10);
259}
260
261/**
262 * create_image - Create a hibernation image.
263 * @platform_mode: Whether or not to use the platform driver.
264 *
265 * Execute device drivers' "late" and "noirq" freeze callbacks, create a
266 * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
267 *
268 * Control reappears in this routine after the subsequent restore.
269 */
270static int create_image(int platform_mode)
271{
272 int error;
273
274 error = dpm_suspend_end(PMSG_FREEZE);
275 if (error) {
276 pr_err("Some devices failed to power down, aborting hibernation\n");
277 return error;
278 }
279
280 error = platform_pre_snapshot(platform_mode);
281 if (error || hibernation_test(TEST_PLATFORM))
282 goto Platform_finish;
283
284 error = disable_nonboot_cpus();
285 if (error || hibernation_test(TEST_CPUS))
286 goto Enable_cpus;
287
288 local_irq_disable();
289
290 error = syscore_suspend();
291 if (error) {
292 pr_err("Some system devices failed to power down, aborting hibernation\n");
293 goto Enable_irqs;
294 }
295
296 if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
297 goto Power_up;
298
299 in_suspend = 1;
300 save_processor_state();
301 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true);
302 error = swsusp_arch_suspend();
303 /* Restore control flow magically appears here */
304 restore_processor_state();
305 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false);
306 if (error)
307 pr_err("Error %d creating hibernation image\n", error);
308
309 if (!in_suspend) {
310 events_check_enabled = false;
311 clear_free_pages();
312 }
313
314 platform_leave(platform_mode);
315
316 Power_up:
317 syscore_resume();
318
319 Enable_irqs:
320 local_irq_enable();
321
322 Enable_cpus:
323 enable_nonboot_cpus();
324
325 Platform_finish:
326 platform_finish(platform_mode);
327
328 dpm_resume_start(in_suspend ?
329 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
330
331 return error;
332}
333
334/**
335 * hibernation_snapshot - Quiesce devices and create a hibernation image.
336 * @platform_mode: If set, use platform driver to prepare for the transition.
337 *
338 * This routine must be called with pm_mutex held.
339 */
340int hibernation_snapshot(int platform_mode)
341{
342 pm_message_t msg;
343 int error;
344
345 pm_suspend_clear_flags();
346 error = platform_begin(platform_mode);
347 if (error)
348 goto Close;
349
350 /* Preallocate image memory before shutting down devices. */
351 error = hibernate_preallocate_memory();
352 if (error)
353 goto Close;
354
355 error = freeze_kernel_threads();
356 if (error)
357 goto Cleanup;
358
359 if (hibernation_test(TEST_FREEZER)) {
360
361 /*
362 * Indicate to the caller that we are returning due to a
363 * successful freezer test.
364 */
365 freezer_test_done = true;
366 goto Thaw;
367 }
368
369 error = dpm_prepare(PMSG_FREEZE);
370 if (error) {
371 dpm_complete(PMSG_RECOVER);
372 goto Thaw;
373 }
374
375 suspend_console();
376 pm_restrict_gfp_mask();
377
378 error = dpm_suspend(PMSG_FREEZE);
379
380 if (error || hibernation_test(TEST_DEVICES))
381 platform_recover(platform_mode);
382 else
383 error = create_image(platform_mode);
384
385 /*
386 * In the case that we call create_image() above, the control
387 * returns here (1) after the image has been created or the
388 * image creation has failed and (2) after a successful restore.
389 */
390
391 /* We may need to release the preallocated image pages here. */
392 if (error || !in_suspend)
393 swsusp_free();
394
395 msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
396 dpm_resume(msg);
397
398 if (error || !in_suspend)
399 pm_restore_gfp_mask();
400
401 resume_console();
402 dpm_complete(msg);
403
404 Close:
405 platform_end(platform_mode);
406 return error;
407
408 Thaw:
409 thaw_kernel_threads();
410 Cleanup:
411 swsusp_free();
412 goto Close;
413}
414
415int __weak hibernate_resume_nonboot_cpu_disable(void)
416{
417 return disable_nonboot_cpus();
418}
419
420/**
421 * resume_target_kernel - Restore system state from a hibernation image.
422 * @platform_mode: Whether or not to use the platform driver.
423 *
424 * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
425 * contents of highmem that have not been restored yet from the image and run
426 * the low-level code that will restore the remaining contents of memory and
427 * switch to the just restored target kernel.
428 */
429static int resume_target_kernel(bool platform_mode)
430{
431 int error;
432
433 error = dpm_suspend_end(PMSG_QUIESCE);
434 if (error) {
435 pr_err("Some devices failed to power down, aborting resume\n");
436 return error;
437 }
438
439 error = platform_pre_restore(platform_mode);
440 if (error)
441 goto Cleanup;
442
443 error = hibernate_resume_nonboot_cpu_disable();
444 if (error)
445 goto Enable_cpus;
446
447 local_irq_disable();
448
449 error = syscore_suspend();
450 if (error)
451 goto Enable_irqs;
452
453 save_processor_state();
454 error = restore_highmem();
455 if (!error) {
456 error = swsusp_arch_resume();
457 /*
458 * The code below is only ever reached in case of a failure.
459 * Otherwise, execution continues at the place where
460 * swsusp_arch_suspend() was called.
461 */
462 BUG_ON(!error);
463 /*
464 * This call to restore_highmem() reverts the changes made by
465 * the previous one.
466 */
467 restore_highmem();
468 }
469 /*
470 * The only reason why swsusp_arch_resume() can fail is memory being
471 * very tight, so we have to free it as soon as we can to avoid
472 * subsequent failures.
473 */
474 swsusp_free();
475 restore_processor_state();
476 touch_softlockup_watchdog();
477
478 syscore_resume();
479
480 Enable_irqs:
481 local_irq_enable();
482
483 Enable_cpus:
484 enable_nonboot_cpus();
485
486 Cleanup:
487 platform_restore_cleanup(platform_mode);
488
489 dpm_resume_start(PMSG_RECOVER);
490
491 return error;
492}
493
494/**
495 * hibernation_restore - Quiesce devices and restore from a hibernation image.
496 * @platform_mode: If set, use platform driver to prepare for the transition.
497 *
498 * This routine must be called with pm_mutex held. If it is successful, control
499 * reappears in the restored target kernel in hibernation_snapshot().
500 */
501int hibernation_restore(int platform_mode)
502{
503 int error;
504
505 pm_prepare_console();
506 suspend_console();
507 pm_restrict_gfp_mask();
508 error = dpm_suspend_start(PMSG_QUIESCE);
509 if (!error) {
510 error = resume_target_kernel(platform_mode);
511 /*
512 * The above should either succeed and jump to the new kernel,
513 * or return with an error. Otherwise things are just
514 * undefined, so let's be paranoid.
515 */
516 BUG_ON(!error);
517 }
518 dpm_resume_end(PMSG_RECOVER);
519 pm_restore_gfp_mask();
520 resume_console();
521 pm_restore_console();
522 return error;
523}
524
525/**
526 * hibernation_platform_enter - Power off the system using the platform driver.
527 */
528int hibernation_platform_enter(void)
529{
530 int error;
531
532 if (!hibernation_ops)
533 return -ENOSYS;
534
535 /*
536 * We have cancelled the power transition by running
537 * hibernation_ops->finish() before saving the image, so we should let
538 * the firmware know that we're going to enter the sleep state after all
539 */
540 error = hibernation_ops->begin();
541 if (error)
542 goto Close;
543
544 entering_platform_hibernation = true;
545 suspend_console();
546 error = dpm_suspend_start(PMSG_HIBERNATE);
547 if (error) {
548 if (hibernation_ops->recover)
549 hibernation_ops->recover();
550 goto Resume_devices;
551 }
552
553 error = dpm_suspend_end(PMSG_HIBERNATE);
554 if (error)
555 goto Resume_devices;
556
557 error = hibernation_ops->prepare();
558 if (error)
559 goto Platform_finish;
560
561 error = disable_nonboot_cpus();
562 if (error)
563 goto Enable_cpus;
564
565 local_irq_disable();
566 syscore_suspend();
567 if (pm_wakeup_pending()) {
568 error = -EAGAIN;
569 goto Power_up;
570 }
571
572 hibernation_ops->enter();
573 /* We should never get here */
574 while (1);
575
576 Power_up:
577 syscore_resume();
578 local_irq_enable();
579
580 Enable_cpus:
581 enable_nonboot_cpus();
582
583 Platform_finish:
584 hibernation_ops->finish();
585
586 dpm_resume_start(PMSG_RESTORE);
587
588 Resume_devices:
589 entering_platform_hibernation = false;
590 dpm_resume_end(PMSG_RESTORE);
591 resume_console();
592
593 Close:
594 hibernation_ops->end();
595
596 return error;
597}
598
599/**
600 * power_down - Shut the machine down for hibernation.
601 *
602 * Use the platform driver, if configured, to put the system into the sleep
603 * state corresponding to hibernation, or try to power it off or reboot,
604 * depending on the value of hibernation_mode.
605 */
606static void power_down(void)
607{
608#ifdef CONFIG_SUSPEND
609 int error;
610
611 if (hibernation_mode == HIBERNATION_SUSPEND) {
612 error = suspend_devices_and_enter(PM_SUSPEND_MEM);
613 if (error) {
614 hibernation_mode = hibernation_ops ?
615 HIBERNATION_PLATFORM :
616 HIBERNATION_SHUTDOWN;
617 } else {
618 /* Restore swap signature. */
619 error = swsusp_unmark();
620 if (error)
621 pr_err("Swap will be unusable! Try swapon -a.\n");
622
623 return;
624 }
625 }
626#endif
627
628 switch (hibernation_mode) {
629 case HIBERNATION_REBOOT:
630 kernel_restart(NULL);
631 break;
632 case HIBERNATION_PLATFORM:
633 hibernation_platform_enter();
634 case HIBERNATION_SHUTDOWN:
635 if (pm_power_off)
636 kernel_power_off();
637 break;
638 }
639 kernel_halt();
640 /*
641 * Valid image is on the disk, if we continue we risk serious data
642 * corruption after resume.
643 */
644 pr_crit("Power down manually\n");
645 while (1)
646 cpu_relax();
647}
648
649static int load_image_and_restore(void)
650{
651 int error;
652 unsigned int flags;
653
654 pm_pr_dbg("Loading hibernation image.\n");
655
656 lock_device_hotplug();
657 error = create_basic_memory_bitmaps();
658 if (error)
659 goto Unlock;
660
661 error = swsusp_read(&flags);
662 swsusp_close(FMODE_READ);
663 if (!error)
664 hibernation_restore(flags & SF_PLATFORM_MODE);
665
666 pr_err("Failed to load hibernation image, recovering.\n");
667 swsusp_free();
668 free_basic_memory_bitmaps();
669 Unlock:
670 unlock_device_hotplug();
671
672 return error;
673}
674
675/**
676 * hibernate - Carry out system hibernation, including saving the image.
677 */
678int hibernate(void)
679{
680 int error, nr_calls = 0;
681 bool snapshot_test = false;
682
683 if (!hibernation_available()) {
684 pm_pr_dbg("Hibernation not available.\n");
685 return -EPERM;
686 }
687
688 lock_system_sleep();
689 /* The snapshot device should not be opened while we're running */
690 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
691 error = -EBUSY;
692 goto Unlock;
693 }
694
695 pr_info("hibernation entry\n");
696 pm_prepare_console();
697 error = __pm_notifier_call_chain(PM_HIBERNATION_PREPARE, -1, &nr_calls);
698 if (error) {
699 nr_calls--;
700 goto Exit;
701 }
702
703 pr_info("Syncing filesystems ... \n");
704 ksys_sync();
705 pr_info("done.\n");
706
707 error = freeze_processes();
708 if (error)
709 goto Exit;
710
711 lock_device_hotplug();
712 /* Allocate memory management structures */
713 error = create_basic_memory_bitmaps();
714 if (error)
715 goto Thaw;
716
717 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
718 if (error || freezer_test_done)
719 goto Free_bitmaps;
720
721 if (in_suspend) {
722 unsigned int flags = 0;
723
724 if (hibernation_mode == HIBERNATION_PLATFORM)
725 flags |= SF_PLATFORM_MODE;
726 if (nocompress)
727 flags |= SF_NOCOMPRESS_MODE;
728 else
729 flags |= SF_CRC32_MODE;
730
731 pm_pr_dbg("Writing image.\n");
732 error = swsusp_write(flags);
733 swsusp_free();
734 if (!error) {
735 if (hibernation_mode == HIBERNATION_TEST_RESUME)
736 snapshot_test = true;
737 else
738 power_down();
739 }
740 in_suspend = 0;
741 pm_restore_gfp_mask();
742 } else {
743 pm_pr_dbg("Image restored successfully.\n");
744 }
745
746 Free_bitmaps:
747 free_basic_memory_bitmaps();
748 Thaw:
749 unlock_device_hotplug();
750 if (snapshot_test) {
751 pm_pr_dbg("Checking hibernation image\n");
752 error = swsusp_check();
753 if (!error)
754 error = load_image_and_restore();
755 }
756 thaw_processes();
757
758 /* Don't bother checking whether freezer_test_done is true */
759 freezer_test_done = false;
760 Exit:
761 __pm_notifier_call_chain(PM_POST_HIBERNATION, nr_calls, NULL);
762 pm_restore_console();
763 atomic_inc(&snapshot_device_available);
764 Unlock:
765 unlock_system_sleep();
766 pr_info("hibernation exit\n");
767
768 return error;
769}
770
771
772/**
773 * software_resume - Resume from a saved hibernation image.
774 *
775 * This routine is called as a late initcall, when all devices have been
776 * discovered and initialized already.
777 *
778 * The image reading code is called to see if there is a hibernation image
779 * available for reading. If that is the case, devices are quiesced and the
780 * contents of memory is restored from the saved image.
781 *
782 * If this is successful, control reappears in the restored target kernel in
783 * hibernation_snapshot() which returns to hibernate(). Otherwise, the routine
784 * attempts to recover gracefully and make the kernel return to the normal mode
785 * of operation.
786 */
787static int software_resume(void)
788{
789 int error, nr_calls = 0;
790
791 /*
792 * If the user said "noresume".. bail out early.
793 */
794 if (noresume || !hibernation_available())
795 return 0;
796
797 /*
798 * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
799 * is configured into the kernel. Since the regular hibernate
800 * trigger path is via sysfs which takes a buffer mutex before
801 * calling hibernate functions (which take pm_mutex) this can
802 * cause lockdep to complain about a possible ABBA deadlock
803 * which cannot happen since we're in the boot code here and
804 * sysfs can't be invoked yet. Therefore, we use a subclass
805 * here to avoid lockdep complaining.
806 */
807 mutex_lock_nested(&pm_mutex, SINGLE_DEPTH_NESTING);
808
809 if (swsusp_resume_device)
810 goto Check_image;
811
812 if (!strlen(resume_file)) {
813 error = -ENOENT;
814 goto Unlock;
815 }
816
817 pm_pr_dbg("Checking hibernation image partition %s\n", resume_file);
818
819 if (resume_delay) {
820 pr_info("Waiting %dsec before reading resume device ...\n",
821 resume_delay);
822 ssleep(resume_delay);
823 }
824
825 /* Check if the device is there */
826 swsusp_resume_device = name_to_dev_t(resume_file);
827
828 /*
829 * name_to_dev_t is ineffective to verify parition if resume_file is in
830 * integer format. (e.g. major:minor)
831 */
832 if (isdigit(resume_file[0]) && resume_wait) {
833 int partno;
834 while (!get_gendisk(swsusp_resume_device, &partno))
835 msleep(10);
836 }
837
838 if (!swsusp_resume_device) {
839 /*
840 * Some device discovery might still be in progress; we need
841 * to wait for this to finish.
842 */
843 wait_for_device_probe();
844
845 if (resume_wait) {
846 while ((swsusp_resume_device = name_to_dev_t(resume_file)) == 0)
847 msleep(10);
848 async_synchronize_full();
849 }
850
851 swsusp_resume_device = name_to_dev_t(resume_file);
852 if (!swsusp_resume_device) {
853 error = -ENODEV;
854 goto Unlock;
855 }
856 }
857
858 Check_image:
859 pm_pr_dbg("Hibernation image partition %d:%d present\n",
860 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
861
862 pm_pr_dbg("Looking for hibernation image.\n");
863 error = swsusp_check();
864 if (error)
865 goto Unlock;
866
867 /* The snapshot device should not be opened while we're running */
868 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
869 error = -EBUSY;
870 swsusp_close(FMODE_READ);
871 goto Unlock;
872 }
873
874 pr_info("resume from hibernation\n");
875 pm_prepare_console();
876 error = __pm_notifier_call_chain(PM_RESTORE_PREPARE, -1, &nr_calls);
877 if (error) {
878 nr_calls--;
879 goto Close_Finish;
880 }
881
882 pm_pr_dbg("Preparing processes for restore.\n");
883 error = freeze_processes();
884 if (error)
885 goto Close_Finish;
886 error = load_image_and_restore();
887 thaw_processes();
888 Finish:
889 __pm_notifier_call_chain(PM_POST_RESTORE, nr_calls, NULL);
890 pm_restore_console();
891 pr_info("resume from hibernation failed (%d)\n", error);
892 atomic_inc(&snapshot_device_available);
893 /* For success case, the suspend path will release the lock */
894 Unlock:
895 mutex_unlock(&pm_mutex);
896 pm_pr_dbg("Hibernation image not present or could not be loaded.\n");
897 return error;
898 Close_Finish:
899 swsusp_close(FMODE_READ);
900 goto Finish;
901}
902
903late_initcall_sync(software_resume);
904
905
906static const char * const hibernation_modes[] = {
907 [HIBERNATION_PLATFORM] = "platform",
908 [HIBERNATION_SHUTDOWN] = "shutdown",
909 [HIBERNATION_REBOOT] = "reboot",
910#ifdef CONFIG_SUSPEND
911 [HIBERNATION_SUSPEND] = "suspend",
912#endif
913 [HIBERNATION_TEST_RESUME] = "test_resume",
914};
915
916/*
917 * /sys/power/disk - Control hibernation mode.
918 *
919 * Hibernation can be handled in several ways. There are a few different ways
920 * to put the system into the sleep state: using the platform driver (e.g. ACPI
921 * or other hibernation_ops), powering it off or rebooting it (for testing
922 * mostly).
923 *
924 * The sysfs file /sys/power/disk provides an interface for selecting the
925 * hibernation mode to use. Reading from this file causes the available modes
926 * to be printed. There are 3 modes that can be supported:
927 *
928 * 'platform'
929 * 'shutdown'
930 * 'reboot'
931 *
932 * If a platform hibernation driver is in use, 'platform' will be supported
933 * and will be used by default. Otherwise, 'shutdown' will be used by default.
934 * The selected option (i.e. the one corresponding to the current value of
935 * hibernation_mode) is enclosed by a square bracket.
936 *
937 * To select a given hibernation mode it is necessary to write the mode's
938 * string representation (as returned by reading from /sys/power/disk) back
939 * into /sys/power/disk.
940 */
941
942static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
943 char *buf)
944{
945 int i;
946 char *start = buf;
947
948 if (!hibernation_available())
949 return sprintf(buf, "[disabled]\n");
950
951 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
952 if (!hibernation_modes[i])
953 continue;
954 switch (i) {
955 case HIBERNATION_SHUTDOWN:
956 case HIBERNATION_REBOOT:
957#ifdef CONFIG_SUSPEND
958 case HIBERNATION_SUSPEND:
959#endif
960 case HIBERNATION_TEST_RESUME:
961 break;
962 case HIBERNATION_PLATFORM:
963 if (hibernation_ops)
964 break;
965 /* not a valid mode, continue with loop */
966 continue;
967 }
968 if (i == hibernation_mode)
969 buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
970 else
971 buf += sprintf(buf, "%s ", hibernation_modes[i]);
972 }
973 buf += sprintf(buf, "\n");
974 return buf-start;
975}
976
977static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
978 const char *buf, size_t n)
979{
980 int error = 0;
981 int i;
982 int len;
983 char *p;
984 int mode = HIBERNATION_INVALID;
985
986 if (!hibernation_available())
987 return -EPERM;
988
989 p = memchr(buf, '\n', n);
990 len = p ? p - buf : n;
991
992 lock_system_sleep();
993 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
994 if (len == strlen(hibernation_modes[i])
995 && !strncmp(buf, hibernation_modes[i], len)) {
996 mode = i;
997 break;
998 }
999 }
1000 if (mode != HIBERNATION_INVALID) {
1001 switch (mode) {
1002 case HIBERNATION_SHUTDOWN:
1003 case HIBERNATION_REBOOT:
1004#ifdef CONFIG_SUSPEND
1005 case HIBERNATION_SUSPEND:
1006#endif
1007 case HIBERNATION_TEST_RESUME:
1008 hibernation_mode = mode;
1009 break;
1010 case HIBERNATION_PLATFORM:
1011 if (hibernation_ops)
1012 hibernation_mode = mode;
1013 else
1014 error = -EINVAL;
1015 }
1016 } else
1017 error = -EINVAL;
1018
1019 if (!error)
1020 pm_pr_dbg("Hibernation mode set to '%s'\n",
1021 hibernation_modes[mode]);
1022 unlock_system_sleep();
1023 return error ? error : n;
1024}
1025
1026power_attr(disk);
1027
1028static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
1029 char *buf)
1030{
1031 return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
1032 MINOR(swsusp_resume_device));
1033}
1034
1035static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
1036 const char *buf, size_t n)
1037{
1038 dev_t res;
1039 int len = n;
1040 char *name;
1041
1042 if (len && buf[len-1] == '\n')
1043 len--;
1044 name = kstrndup(buf, len, GFP_KERNEL);
1045 if (!name)
1046 return -ENOMEM;
1047
1048 res = name_to_dev_t(name);
1049 kfree(name);
1050 if (!res)
1051 return -EINVAL;
1052
1053 lock_system_sleep();
1054 swsusp_resume_device = res;
1055 unlock_system_sleep();
1056 pm_pr_dbg("Configured resume from disk to %u\n", swsusp_resume_device);
1057 noresume = 0;
1058 software_resume();
1059 return n;
1060}
1061
1062power_attr(resume);
1063
1064static ssize_t resume_offset_show(struct kobject *kobj,
1065 struct kobj_attribute *attr, char *buf)
1066{
1067 return sprintf(buf, "%llu\n", (unsigned long long)swsusp_resume_block);
1068}
1069
1070static ssize_t resume_offset_store(struct kobject *kobj,
1071 struct kobj_attribute *attr, const char *buf,
1072 size_t n)
1073{
1074 unsigned long long offset;
1075 int rc;
1076
1077 rc = kstrtoull(buf, 0, &offset);
1078 if (rc)
1079 return rc;
1080 swsusp_resume_block = offset;
1081
1082 return n;
1083}
1084
1085power_attr(resume_offset);
1086
1087static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
1088 char *buf)
1089{
1090 return sprintf(buf, "%lu\n", image_size);
1091}
1092
1093static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
1094 const char *buf, size_t n)
1095{
1096 unsigned long size;
1097
1098 if (sscanf(buf, "%lu", &size) == 1) {
1099 image_size = size;
1100 return n;
1101 }
1102
1103 return -EINVAL;
1104}
1105
1106power_attr(image_size);
1107
1108static ssize_t reserved_size_show(struct kobject *kobj,
1109 struct kobj_attribute *attr, char *buf)
1110{
1111 return sprintf(buf, "%lu\n", reserved_size);
1112}
1113
1114static ssize_t reserved_size_store(struct kobject *kobj,
1115 struct kobj_attribute *attr,
1116 const char *buf, size_t n)
1117{
1118 unsigned long size;
1119
1120 if (sscanf(buf, "%lu", &size) == 1) {
1121 reserved_size = size;
1122 return n;
1123 }
1124
1125 return -EINVAL;
1126}
1127
1128power_attr(reserved_size);
1129
1130static struct attribute * g[] = {
1131 &disk_attr.attr,
1132 &resume_offset_attr.attr,
1133 &resume_attr.attr,
1134 &image_size_attr.attr,
1135 &reserved_size_attr.attr,
1136 NULL,
1137};
1138
1139
1140static const struct attribute_group attr_group = {
1141 .attrs = g,
1142};
1143
1144
1145static int __init pm_disk_init(void)
1146{
1147 return sysfs_create_group(power_kobj, &attr_group);
1148}
1149
1150core_initcall(pm_disk_init);
1151
1152
1153static int __init resume_setup(char *str)
1154{
1155 if (noresume)
1156 return 1;
1157
1158 strncpy( resume_file, str, 255 );
1159 return 1;
1160}
1161
1162static int __init resume_offset_setup(char *str)
1163{
1164 unsigned long long offset;
1165
1166 if (noresume)
1167 return 1;
1168
1169 if (sscanf(str, "%llu", &offset) == 1)
1170 swsusp_resume_block = offset;
1171
1172 return 1;
1173}
1174
1175static int __init hibernate_setup(char *str)
1176{
1177 if (!strncmp(str, "noresume", 8)) {
1178 noresume = 1;
1179 } else if (!strncmp(str, "nocompress", 10)) {
1180 nocompress = 1;
1181 } else if (!strncmp(str, "no", 2)) {
1182 noresume = 1;
1183 nohibernate = 1;
1184 } else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)
1185 && !strncmp(str, "protect_image", 13)) {
1186 enable_restore_image_protection();
1187 }
1188 return 1;
1189}
1190
1191static int __init noresume_setup(char *str)
1192{
1193 noresume = 1;
1194 return 1;
1195}
1196
1197static int __init resumewait_setup(char *str)
1198{
1199 resume_wait = 1;
1200 return 1;
1201}
1202
1203static int __init resumedelay_setup(char *str)
1204{
1205 int rc = kstrtouint(str, 0, &resume_delay);
1206
1207 if (rc)
1208 return rc;
1209 return 1;
1210}
1211
1212static int __init nohibernate_setup(char *str)
1213{
1214 noresume = 1;
1215 nohibernate = 1;
1216 return 1;
1217}
1218
1219__setup("noresume", noresume_setup);
1220__setup("resume_offset=", resume_offset_setup);
1221__setup("resume=", resume_setup);
1222__setup("hibernate=", hibernate_setup);
1223__setup("resumewait", resumewait_setup);
1224__setup("resumedelay=", resumedelay_setup);
1225__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);