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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * kernel/power/hibernate.c - Hibernation (a.k.a suspend-to-disk) support.
4 *
5 * Copyright (c) 2003 Patrick Mochel
6 * Copyright (c) 2003 Open Source Development Lab
7 * Copyright (c) 2004 Pavel Machek <pavel@ucw.cz>
8 * Copyright (c) 2009 Rafael J. Wysocki, Novell Inc.
9 * Copyright (C) 2012 Bojan Smojver <bojan@rexursive.com>
10 */
11
12#define pr_fmt(fmt) "PM: hibernation: " fmt
13
14#include <linux/blkdev.h>
15#include <linux/export.h>
16#include <linux/suspend.h>
17#include <linux/reboot.h>
18#include <linux/string.h>
19#include <linux/device.h>
20#include <linux/async.h>
21#include <linux/delay.h>
22#include <linux/fs.h>
23#include <linux/mount.h>
24#include <linux/pm.h>
25#include <linux/nmi.h>
26#include <linux/console.h>
27#include <linux/cpu.h>
28#include <linux/freezer.h>
29#include <linux/gfp.h>
30#include <linux/syscore_ops.h>
31#include <linux/ctype.h>
32#include <linux/ktime.h>
33#include <linux/security.h>
34#include <linux/secretmem.h>
35#include <trace/events/power.h>
36
37#include "power.h"
38
39
40static int nocompress;
41static int noresume;
42static int nohibernate;
43static int resume_wait;
44static unsigned int resume_delay;
45static char resume_file[256] = CONFIG_PM_STD_PARTITION;
46dev_t swsusp_resume_device;
47sector_t swsusp_resume_block;
48__visible int in_suspend __nosavedata;
49
50static char hibernate_compressor[CRYPTO_MAX_ALG_NAME] = CONFIG_HIBERNATION_DEF_COMP;
51
52/*
53 * Compression/decompression algorithm to be used while saving/loading
54 * image to/from disk. This would later be used in 'kernel/power/swap.c'
55 * to allocate comp streams.
56 */
57char hib_comp_algo[CRYPTO_MAX_ALG_NAME];
58
59enum {
60 HIBERNATION_INVALID,
61 HIBERNATION_PLATFORM,
62 HIBERNATION_SHUTDOWN,
63 HIBERNATION_REBOOT,
64#ifdef CONFIG_SUSPEND
65 HIBERNATION_SUSPEND,
66#endif
67 HIBERNATION_TEST_RESUME,
68 /* keep last */
69 __HIBERNATION_AFTER_LAST
70};
71#define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
72#define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
73
74static int hibernation_mode = HIBERNATION_SHUTDOWN;
75
76bool freezer_test_done;
77
78static const struct platform_hibernation_ops *hibernation_ops;
79
80static atomic_t hibernate_atomic = ATOMIC_INIT(1);
81
82bool hibernate_acquire(void)
83{
84 return atomic_add_unless(&hibernate_atomic, -1, 0);
85}
86
87void hibernate_release(void)
88{
89 atomic_inc(&hibernate_atomic);
90}
91
92bool hibernation_available(void)
93{
94 return nohibernate == 0 &&
95 !security_locked_down(LOCKDOWN_HIBERNATION) &&
96 !secretmem_active() && !cxl_mem_active();
97}
98
99/**
100 * hibernation_set_ops - Set the global hibernate operations.
101 * @ops: Hibernation operations to use in subsequent hibernation transitions.
102 */
103void hibernation_set_ops(const struct platform_hibernation_ops *ops)
104{
105 unsigned int sleep_flags;
106
107 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
108 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
109 && ops->restore_cleanup && ops->leave)) {
110 WARN_ON(1);
111 return;
112 }
113
114 sleep_flags = lock_system_sleep();
115
116 hibernation_ops = ops;
117 if (ops)
118 hibernation_mode = HIBERNATION_PLATFORM;
119 else if (hibernation_mode == HIBERNATION_PLATFORM)
120 hibernation_mode = HIBERNATION_SHUTDOWN;
121
122 unlock_system_sleep(sleep_flags);
123}
124EXPORT_SYMBOL_GPL(hibernation_set_ops);
125
126static bool entering_platform_hibernation;
127
128bool system_entering_hibernation(void)
129{
130 return entering_platform_hibernation;
131}
132EXPORT_SYMBOL(system_entering_hibernation);
133
134#ifdef CONFIG_PM_DEBUG
135static void hibernation_debug_sleep(void)
136{
137 pr_info("debug: Waiting for 5 seconds.\n");
138 mdelay(5000);
139}
140
141static int hibernation_test(int level)
142{
143 if (pm_test_level == level) {
144 hibernation_debug_sleep();
145 return 1;
146 }
147 return 0;
148}
149#else /* !CONFIG_PM_DEBUG */
150static int hibernation_test(int level) { return 0; }
151#endif /* !CONFIG_PM_DEBUG */
152
153/**
154 * platform_begin - Call platform to start hibernation.
155 * @platform_mode: Whether or not to use the platform driver.
156 */
157static int platform_begin(int platform_mode)
158{
159 return (platform_mode && hibernation_ops) ?
160 hibernation_ops->begin(PMSG_FREEZE) : 0;
161}
162
163/**
164 * platform_end - Call platform to finish transition to the working state.
165 * @platform_mode: Whether or not to use the platform driver.
166 */
167static void platform_end(int platform_mode)
168{
169 if (platform_mode && hibernation_ops)
170 hibernation_ops->end();
171}
172
173/**
174 * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
175 * @platform_mode: Whether or not to use the platform driver.
176 *
177 * Use the platform driver to prepare the system for creating a hibernate image,
178 * if so configured, and return an error code if that fails.
179 */
180
181static int platform_pre_snapshot(int platform_mode)
182{
183 return (platform_mode && hibernation_ops) ?
184 hibernation_ops->pre_snapshot() : 0;
185}
186
187/**
188 * platform_leave - Call platform to prepare a transition to the working state.
189 * @platform_mode: Whether or not to use the platform driver.
190 *
191 * Use the platform driver prepare to prepare the machine for switching to the
192 * normal mode of operation.
193 *
194 * This routine is called on one CPU with interrupts disabled.
195 */
196static void platform_leave(int platform_mode)
197{
198 if (platform_mode && hibernation_ops)
199 hibernation_ops->leave();
200}
201
202/**
203 * platform_finish - Call platform to switch the system to the working state.
204 * @platform_mode: Whether or not to use the platform driver.
205 *
206 * Use the platform driver to switch the machine to the normal mode of
207 * operation.
208 *
209 * This routine must be called after platform_prepare().
210 */
211static void platform_finish(int platform_mode)
212{
213 if (platform_mode && hibernation_ops)
214 hibernation_ops->finish();
215}
216
217/**
218 * platform_pre_restore - Prepare for hibernate image restoration.
219 * @platform_mode: Whether or not to use the platform driver.
220 *
221 * Use the platform driver to prepare the system for resume from a hibernation
222 * image.
223 *
224 * If the restore fails after this function has been called,
225 * platform_restore_cleanup() must be called.
226 */
227static int platform_pre_restore(int platform_mode)
228{
229 return (platform_mode && hibernation_ops) ?
230 hibernation_ops->pre_restore() : 0;
231}
232
233/**
234 * platform_restore_cleanup - Switch to the working state after failing restore.
235 * @platform_mode: Whether or not to use the platform driver.
236 *
237 * Use the platform driver to switch the system to the normal mode of operation
238 * after a failing restore.
239 *
240 * If platform_pre_restore() has been called before the failing restore, this
241 * function must be called too, regardless of the result of
242 * platform_pre_restore().
243 */
244static void platform_restore_cleanup(int platform_mode)
245{
246 if (platform_mode && hibernation_ops)
247 hibernation_ops->restore_cleanup();
248}
249
250/**
251 * platform_recover - Recover from a failure to suspend devices.
252 * @platform_mode: Whether or not to use the platform driver.
253 */
254static void platform_recover(int platform_mode)
255{
256 if (platform_mode && hibernation_ops && hibernation_ops->recover)
257 hibernation_ops->recover();
258}
259
260/**
261 * swsusp_show_speed - Print time elapsed between two events during hibernation.
262 * @start: Starting event.
263 * @stop: Final event.
264 * @nr_pages: Number of memory pages processed between @start and @stop.
265 * @msg: Additional diagnostic message to print.
266 */
267void swsusp_show_speed(ktime_t start, ktime_t stop,
268 unsigned nr_pages, char *msg)
269{
270 ktime_t diff;
271 u64 elapsed_centisecs64;
272 unsigned int centisecs;
273 unsigned int k;
274 unsigned int kps;
275
276 diff = ktime_sub(stop, start);
277 elapsed_centisecs64 = ktime_divns(diff, 10*NSEC_PER_MSEC);
278 centisecs = elapsed_centisecs64;
279 if (centisecs == 0)
280 centisecs = 1; /* avoid div-by-zero */
281 k = nr_pages * (PAGE_SIZE / 1024);
282 kps = (k * 100) / centisecs;
283 pr_info("%s %u kbytes in %u.%02u seconds (%u.%02u MB/s)\n",
284 msg, k, centisecs / 100, centisecs % 100, kps / 1000,
285 (kps % 1000) / 10);
286}
287
288__weak int arch_resume_nosmt(void)
289{
290 return 0;
291}
292
293/**
294 * create_image - Create a hibernation image.
295 * @platform_mode: Whether or not to use the platform driver.
296 *
297 * Execute device drivers' "late" and "noirq" freeze callbacks, create a
298 * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
299 *
300 * Control reappears in this routine after the subsequent restore.
301 */
302static int create_image(int platform_mode)
303{
304 int error;
305
306 error = dpm_suspend_end(PMSG_FREEZE);
307 if (error) {
308 pr_err("Some devices failed to power down, aborting\n");
309 return error;
310 }
311
312 error = platform_pre_snapshot(platform_mode);
313 if (error || hibernation_test(TEST_PLATFORM))
314 goto Platform_finish;
315
316 error = pm_sleep_disable_secondary_cpus();
317 if (error || hibernation_test(TEST_CPUS))
318 goto Enable_cpus;
319
320 local_irq_disable();
321
322 system_state = SYSTEM_SUSPEND;
323
324 error = syscore_suspend();
325 if (error) {
326 pr_err("Some system devices failed to power down, aborting\n");
327 goto Enable_irqs;
328 }
329
330 if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
331 goto Power_up;
332
333 in_suspend = 1;
334 save_processor_state();
335 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true);
336 error = swsusp_arch_suspend();
337 /* Restore control flow magically appears here */
338 restore_processor_state();
339 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false);
340 if (error)
341 pr_err("Error %d creating image\n", error);
342
343 if (!in_suspend) {
344 events_check_enabled = false;
345 clear_or_poison_free_pages();
346 }
347
348 platform_leave(platform_mode);
349
350 Power_up:
351 syscore_resume();
352
353 Enable_irqs:
354 system_state = SYSTEM_RUNNING;
355 local_irq_enable();
356
357 Enable_cpus:
358 pm_sleep_enable_secondary_cpus();
359
360 /* Allow architectures to do nosmt-specific post-resume dances */
361 if (!in_suspend)
362 error = arch_resume_nosmt();
363
364 Platform_finish:
365 platform_finish(platform_mode);
366
367 dpm_resume_start(in_suspend ?
368 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
369
370 return error;
371}
372
373/**
374 * hibernation_snapshot - Quiesce devices and create a hibernation image.
375 * @platform_mode: If set, use platform driver to prepare for the transition.
376 *
377 * This routine must be called with system_transition_mutex held.
378 */
379int hibernation_snapshot(int platform_mode)
380{
381 pm_message_t msg;
382 int error;
383
384 pm_suspend_clear_flags();
385 error = platform_begin(platform_mode);
386 if (error)
387 goto Close;
388
389 /* Preallocate image memory before shutting down devices. */
390 error = hibernate_preallocate_memory();
391 if (error)
392 goto Close;
393
394 error = freeze_kernel_threads();
395 if (error)
396 goto Cleanup;
397
398 if (hibernation_test(TEST_FREEZER)) {
399
400 /*
401 * Indicate to the caller that we are returning due to a
402 * successful freezer test.
403 */
404 freezer_test_done = true;
405 goto Thaw;
406 }
407
408 error = dpm_prepare(PMSG_FREEZE);
409 if (error) {
410 dpm_complete(PMSG_RECOVER);
411 goto Thaw;
412 }
413
414 suspend_console();
415 pm_restrict_gfp_mask();
416
417 error = dpm_suspend(PMSG_FREEZE);
418
419 if (error || hibernation_test(TEST_DEVICES))
420 platform_recover(platform_mode);
421 else
422 error = create_image(platform_mode);
423
424 /*
425 * In the case that we call create_image() above, the control
426 * returns here (1) after the image has been created or the
427 * image creation has failed and (2) after a successful restore.
428 */
429
430 /* We may need to release the preallocated image pages here. */
431 if (error || !in_suspend)
432 swsusp_free();
433
434 msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
435 dpm_resume(msg);
436
437 if (error || !in_suspend)
438 pm_restore_gfp_mask();
439
440 resume_console();
441 dpm_complete(msg);
442
443 Close:
444 platform_end(platform_mode);
445 return error;
446
447 Thaw:
448 thaw_kernel_threads();
449 Cleanup:
450 swsusp_free();
451 goto Close;
452}
453
454int __weak hibernate_resume_nonboot_cpu_disable(void)
455{
456 return suspend_disable_secondary_cpus();
457}
458
459/**
460 * resume_target_kernel - Restore system state from a hibernation image.
461 * @platform_mode: Whether or not to use the platform driver.
462 *
463 * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
464 * contents of highmem that have not been restored yet from the image and run
465 * the low-level code that will restore the remaining contents of memory and
466 * switch to the just restored target kernel.
467 */
468static int resume_target_kernel(bool platform_mode)
469{
470 int error;
471
472 error = dpm_suspend_end(PMSG_QUIESCE);
473 if (error) {
474 pr_err("Some devices failed to power down, aborting resume\n");
475 return error;
476 }
477
478 error = platform_pre_restore(platform_mode);
479 if (error)
480 goto Cleanup;
481
482 cpuidle_pause();
483
484 error = hibernate_resume_nonboot_cpu_disable();
485 if (error)
486 goto Enable_cpus;
487
488 local_irq_disable();
489 system_state = SYSTEM_SUSPEND;
490
491 error = syscore_suspend();
492 if (error)
493 goto Enable_irqs;
494
495 save_processor_state();
496 error = restore_highmem();
497 if (!error) {
498 error = swsusp_arch_resume();
499 /*
500 * The code below is only ever reached in case of a failure.
501 * Otherwise, execution continues at the place where
502 * swsusp_arch_suspend() was called.
503 */
504 BUG_ON(!error);
505 /*
506 * This call to restore_highmem() reverts the changes made by
507 * the previous one.
508 */
509 restore_highmem();
510 }
511 /*
512 * The only reason why swsusp_arch_resume() can fail is memory being
513 * very tight, so we have to free it as soon as we can to avoid
514 * subsequent failures.
515 */
516 swsusp_free();
517 restore_processor_state();
518 touch_softlockup_watchdog();
519
520 syscore_resume();
521
522 Enable_irqs:
523 system_state = SYSTEM_RUNNING;
524 local_irq_enable();
525
526 Enable_cpus:
527 pm_sleep_enable_secondary_cpus();
528
529 Cleanup:
530 platform_restore_cleanup(platform_mode);
531
532 dpm_resume_start(PMSG_RECOVER);
533
534 return error;
535}
536
537/**
538 * hibernation_restore - Quiesce devices and restore from a hibernation image.
539 * @platform_mode: If set, use platform driver to prepare for the transition.
540 *
541 * This routine must be called with system_transition_mutex held. If it is
542 * successful, control reappears in the restored target kernel in
543 * hibernation_snapshot().
544 */
545int hibernation_restore(int platform_mode)
546{
547 int error;
548
549 pm_prepare_console();
550 suspend_console();
551 pm_restrict_gfp_mask();
552 error = dpm_suspend_start(PMSG_QUIESCE);
553 if (!error) {
554 error = resume_target_kernel(platform_mode);
555 /*
556 * The above should either succeed and jump to the new kernel,
557 * or return with an error. Otherwise things are just
558 * undefined, so let's be paranoid.
559 */
560 BUG_ON(!error);
561 }
562 dpm_resume_end(PMSG_RECOVER);
563 pm_restore_gfp_mask();
564 resume_console();
565 pm_restore_console();
566 return error;
567}
568
569/**
570 * hibernation_platform_enter - Power off the system using the platform driver.
571 */
572int hibernation_platform_enter(void)
573{
574 int error;
575
576 if (!hibernation_ops)
577 return -ENOSYS;
578
579 /*
580 * We have cancelled the power transition by running
581 * hibernation_ops->finish() before saving the image, so we should let
582 * the firmware know that we're going to enter the sleep state after all
583 */
584 error = hibernation_ops->begin(PMSG_HIBERNATE);
585 if (error)
586 goto Close;
587
588 entering_platform_hibernation = true;
589 suspend_console();
590 error = dpm_suspend_start(PMSG_HIBERNATE);
591 if (error) {
592 if (hibernation_ops->recover)
593 hibernation_ops->recover();
594 goto Resume_devices;
595 }
596
597 error = dpm_suspend_end(PMSG_HIBERNATE);
598 if (error)
599 goto Resume_devices;
600
601 error = hibernation_ops->prepare();
602 if (error)
603 goto Platform_finish;
604
605 error = pm_sleep_disable_secondary_cpus();
606 if (error)
607 goto Enable_cpus;
608
609 local_irq_disable();
610 system_state = SYSTEM_SUSPEND;
611
612 error = syscore_suspend();
613 if (error)
614 goto Enable_irqs;
615
616 if (pm_wakeup_pending()) {
617 error = -EAGAIN;
618 goto Power_up;
619 }
620
621 hibernation_ops->enter();
622 /* We should never get here */
623 while (1);
624
625 Power_up:
626 syscore_resume();
627 Enable_irqs:
628 system_state = SYSTEM_RUNNING;
629 local_irq_enable();
630
631 Enable_cpus:
632 pm_sleep_enable_secondary_cpus();
633
634 Platform_finish:
635 hibernation_ops->finish();
636
637 dpm_resume_start(PMSG_RESTORE);
638
639 Resume_devices:
640 entering_platform_hibernation = false;
641 dpm_resume_end(PMSG_RESTORE);
642 resume_console();
643
644 Close:
645 hibernation_ops->end();
646
647 return error;
648}
649
650/**
651 * power_down - Shut the machine down for hibernation.
652 *
653 * Use the platform driver, if configured, to put the system into the sleep
654 * state corresponding to hibernation, or try to power it off or reboot,
655 * depending on the value of hibernation_mode.
656 */
657static void power_down(void)
658{
659 int error;
660
661#ifdef CONFIG_SUSPEND
662 if (hibernation_mode == HIBERNATION_SUSPEND) {
663 error = suspend_devices_and_enter(mem_sleep_current);
664 if (error) {
665 hibernation_mode = hibernation_ops ?
666 HIBERNATION_PLATFORM :
667 HIBERNATION_SHUTDOWN;
668 } else {
669 /* Restore swap signature. */
670 error = swsusp_unmark();
671 if (error)
672 pr_err("Swap will be unusable! Try swapon -a.\n");
673
674 return;
675 }
676 }
677#endif
678
679 switch (hibernation_mode) {
680 case HIBERNATION_REBOOT:
681 kernel_restart(NULL);
682 break;
683 case HIBERNATION_PLATFORM:
684 error = hibernation_platform_enter();
685 if (error == -EAGAIN || error == -EBUSY) {
686 swsusp_unmark();
687 events_check_enabled = false;
688 pr_info("Wakeup event detected during hibernation, rolling back.\n");
689 return;
690 }
691 fallthrough;
692 case HIBERNATION_SHUTDOWN:
693 if (kernel_can_power_off()) {
694 entering_platform_hibernation = true;
695 kernel_power_off();
696 entering_platform_hibernation = false;
697 }
698 break;
699 }
700 kernel_halt();
701 /*
702 * Valid image is on the disk, if we continue we risk serious data
703 * corruption after resume.
704 */
705 pr_crit("Power down manually\n");
706 while (1)
707 cpu_relax();
708}
709
710static int load_image_and_restore(void)
711{
712 int error;
713 unsigned int flags;
714
715 pm_pr_dbg("Loading hibernation image.\n");
716
717 lock_device_hotplug();
718 error = create_basic_memory_bitmaps();
719 if (error) {
720 swsusp_close();
721 goto Unlock;
722 }
723
724 error = swsusp_read(&flags);
725 swsusp_close();
726 if (!error)
727 error = hibernation_restore(flags & SF_PLATFORM_MODE);
728
729 pr_err("Failed to load image, recovering.\n");
730 swsusp_free();
731 free_basic_memory_bitmaps();
732 Unlock:
733 unlock_device_hotplug();
734
735 return error;
736}
737
738#define COMPRESSION_ALGO_LZO "lzo"
739#define COMPRESSION_ALGO_LZ4 "lz4"
740
741/**
742 * hibernate - Carry out system hibernation, including saving the image.
743 */
744int hibernate(void)
745{
746 bool snapshot_test = false;
747 unsigned int sleep_flags;
748 int error;
749
750 if (!hibernation_available()) {
751 pm_pr_dbg("Hibernation not available.\n");
752 return -EPERM;
753 }
754
755 /*
756 * Query for the compression algorithm support if compression is enabled.
757 */
758 if (!nocompress) {
759 strscpy(hib_comp_algo, hibernate_compressor, sizeof(hib_comp_algo));
760 if (crypto_has_comp(hib_comp_algo, 0, 0) != 1) {
761 pr_err("%s compression is not available\n", hib_comp_algo);
762 return -EOPNOTSUPP;
763 }
764 }
765
766 sleep_flags = lock_system_sleep();
767 /* The snapshot device should not be opened while we're running */
768 if (!hibernate_acquire()) {
769 error = -EBUSY;
770 goto Unlock;
771 }
772
773 pr_info("hibernation entry\n");
774 pm_prepare_console();
775 error = pm_notifier_call_chain_robust(PM_HIBERNATION_PREPARE, PM_POST_HIBERNATION);
776 if (error)
777 goto Restore;
778
779 ksys_sync_helper();
780
781 error = freeze_processes();
782 if (error)
783 goto Exit;
784
785 lock_device_hotplug();
786 /* Allocate memory management structures */
787 error = create_basic_memory_bitmaps();
788 if (error)
789 goto Thaw;
790
791 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
792 if (error || freezer_test_done)
793 goto Free_bitmaps;
794
795 if (in_suspend) {
796 unsigned int flags = 0;
797
798 if (hibernation_mode == HIBERNATION_PLATFORM)
799 flags |= SF_PLATFORM_MODE;
800 if (nocompress) {
801 flags |= SF_NOCOMPRESS_MODE;
802 } else {
803 flags |= SF_CRC32_MODE;
804
805 /*
806 * By default, LZO compression is enabled. Use SF_COMPRESSION_ALG_LZ4
807 * to override this behaviour and use LZ4.
808 *
809 * Refer kernel/power/power.h for more details
810 */
811
812 if (!strcmp(hib_comp_algo, COMPRESSION_ALGO_LZ4))
813 flags |= SF_COMPRESSION_ALG_LZ4;
814 else
815 flags |= SF_COMPRESSION_ALG_LZO;
816 }
817
818 pm_pr_dbg("Writing hibernation image.\n");
819 error = swsusp_write(flags);
820 swsusp_free();
821 if (!error) {
822 if (hibernation_mode == HIBERNATION_TEST_RESUME)
823 snapshot_test = true;
824 else
825 power_down();
826 }
827 in_suspend = 0;
828 pm_restore_gfp_mask();
829 } else {
830 pm_pr_dbg("Hibernation image restored successfully.\n");
831 }
832
833 Free_bitmaps:
834 free_basic_memory_bitmaps();
835 Thaw:
836 unlock_device_hotplug();
837 if (snapshot_test) {
838 pm_pr_dbg("Checking hibernation image\n");
839 error = swsusp_check(false);
840 if (!error)
841 error = load_image_and_restore();
842 }
843 thaw_processes();
844
845 /* Don't bother checking whether freezer_test_done is true */
846 freezer_test_done = false;
847 Exit:
848 pm_notifier_call_chain(PM_POST_HIBERNATION);
849 Restore:
850 pm_restore_console();
851 hibernate_release();
852 Unlock:
853 unlock_system_sleep(sleep_flags);
854 pr_info("hibernation exit\n");
855
856 return error;
857}
858
859/**
860 * hibernate_quiet_exec - Execute a function with all devices frozen.
861 * @func: Function to execute.
862 * @data: Data pointer to pass to @func.
863 *
864 * Return the @func return value or an error code if it cannot be executed.
865 */
866int hibernate_quiet_exec(int (*func)(void *data), void *data)
867{
868 unsigned int sleep_flags;
869 int error;
870
871 sleep_flags = lock_system_sleep();
872
873 if (!hibernate_acquire()) {
874 error = -EBUSY;
875 goto unlock;
876 }
877
878 pm_prepare_console();
879
880 error = pm_notifier_call_chain_robust(PM_HIBERNATION_PREPARE, PM_POST_HIBERNATION);
881 if (error)
882 goto restore;
883
884 error = freeze_processes();
885 if (error)
886 goto exit;
887
888 lock_device_hotplug();
889
890 pm_suspend_clear_flags();
891
892 error = platform_begin(true);
893 if (error)
894 goto thaw;
895
896 error = freeze_kernel_threads();
897 if (error)
898 goto thaw;
899
900 error = dpm_prepare(PMSG_FREEZE);
901 if (error)
902 goto dpm_complete;
903
904 suspend_console();
905
906 error = dpm_suspend(PMSG_FREEZE);
907 if (error)
908 goto dpm_resume;
909
910 error = dpm_suspend_end(PMSG_FREEZE);
911 if (error)
912 goto dpm_resume;
913
914 error = platform_pre_snapshot(true);
915 if (error)
916 goto skip;
917
918 error = func(data);
919
920skip:
921 platform_finish(true);
922
923 dpm_resume_start(PMSG_THAW);
924
925dpm_resume:
926 dpm_resume(PMSG_THAW);
927
928 resume_console();
929
930dpm_complete:
931 dpm_complete(PMSG_THAW);
932
933 thaw_kernel_threads();
934
935thaw:
936 platform_end(true);
937
938 unlock_device_hotplug();
939
940 thaw_processes();
941
942exit:
943 pm_notifier_call_chain(PM_POST_HIBERNATION);
944
945restore:
946 pm_restore_console();
947
948 hibernate_release();
949
950unlock:
951 unlock_system_sleep(sleep_flags);
952
953 return error;
954}
955EXPORT_SYMBOL_GPL(hibernate_quiet_exec);
956
957static int __init find_resume_device(void)
958{
959 if (!strlen(resume_file))
960 return -ENOENT;
961
962 pm_pr_dbg("Checking hibernation image partition %s\n", resume_file);
963
964 if (resume_delay) {
965 pr_info("Waiting %dsec before reading resume device ...\n",
966 resume_delay);
967 ssleep(resume_delay);
968 }
969
970 /* Check if the device is there */
971 if (!early_lookup_bdev(resume_file, &swsusp_resume_device))
972 return 0;
973
974 /*
975 * Some device discovery might still be in progress; we need to wait for
976 * this to finish.
977 */
978 wait_for_device_probe();
979 if (resume_wait) {
980 while (early_lookup_bdev(resume_file, &swsusp_resume_device))
981 msleep(10);
982 async_synchronize_full();
983 }
984
985 return early_lookup_bdev(resume_file, &swsusp_resume_device);
986}
987
988static int software_resume(void)
989{
990 int error;
991
992 pm_pr_dbg("Hibernation image partition %d:%d present\n",
993 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
994
995 pm_pr_dbg("Looking for hibernation image.\n");
996
997 mutex_lock(&system_transition_mutex);
998 error = swsusp_check(true);
999 if (error)
1000 goto Unlock;
1001
1002 /*
1003 * Check if the hibernation image is compressed. If so, query for
1004 * the algorithm support.
1005 */
1006 if (!(swsusp_header_flags & SF_NOCOMPRESS_MODE)) {
1007 if (swsusp_header_flags & SF_COMPRESSION_ALG_LZ4)
1008 strscpy(hib_comp_algo, COMPRESSION_ALGO_LZ4, sizeof(hib_comp_algo));
1009 else
1010 strscpy(hib_comp_algo, COMPRESSION_ALGO_LZO, sizeof(hib_comp_algo));
1011 if (crypto_has_comp(hib_comp_algo, 0, 0) != 1) {
1012 pr_err("%s compression is not available\n", hib_comp_algo);
1013 error = -EOPNOTSUPP;
1014 goto Unlock;
1015 }
1016 }
1017
1018 /* The snapshot device should not be opened while we're running */
1019 if (!hibernate_acquire()) {
1020 error = -EBUSY;
1021 swsusp_close();
1022 goto Unlock;
1023 }
1024
1025 pr_info("resume from hibernation\n");
1026 pm_prepare_console();
1027 error = pm_notifier_call_chain_robust(PM_RESTORE_PREPARE, PM_POST_RESTORE);
1028 if (error)
1029 goto Restore;
1030
1031 pm_pr_dbg("Preparing processes for hibernation restore.\n");
1032 error = freeze_processes();
1033 if (error)
1034 goto Close_Finish;
1035
1036 error = freeze_kernel_threads();
1037 if (error) {
1038 thaw_processes();
1039 goto Close_Finish;
1040 }
1041
1042 error = load_image_and_restore();
1043 thaw_processes();
1044 Finish:
1045 pm_notifier_call_chain(PM_POST_RESTORE);
1046 Restore:
1047 pm_restore_console();
1048 pr_info("resume failed (%d)\n", error);
1049 hibernate_release();
1050 /* For success case, the suspend path will release the lock */
1051 Unlock:
1052 mutex_unlock(&system_transition_mutex);
1053 pm_pr_dbg("Hibernation image not present or could not be loaded.\n");
1054 return error;
1055 Close_Finish:
1056 swsusp_close();
1057 goto Finish;
1058}
1059
1060/**
1061 * software_resume_initcall - Resume from a saved hibernation image.
1062 *
1063 * This routine is called as a late initcall, when all devices have been
1064 * discovered and initialized already.
1065 *
1066 * The image reading code is called to see if there is a hibernation image
1067 * available for reading. If that is the case, devices are quiesced and the
1068 * contents of memory is restored from the saved image.
1069 *
1070 * If this is successful, control reappears in the restored target kernel in
1071 * hibernation_snapshot() which returns to hibernate(). Otherwise, the routine
1072 * attempts to recover gracefully and make the kernel return to the normal mode
1073 * of operation.
1074 */
1075static int __init software_resume_initcall(void)
1076{
1077 /*
1078 * If the user said "noresume".. bail out early.
1079 */
1080 if (noresume || !hibernation_available())
1081 return 0;
1082
1083 if (!swsusp_resume_device) {
1084 int error = find_resume_device();
1085
1086 if (error)
1087 return error;
1088 }
1089
1090 return software_resume();
1091}
1092late_initcall_sync(software_resume_initcall);
1093
1094
1095static const char * const hibernation_modes[] = {
1096 [HIBERNATION_PLATFORM] = "platform",
1097 [HIBERNATION_SHUTDOWN] = "shutdown",
1098 [HIBERNATION_REBOOT] = "reboot",
1099#ifdef CONFIG_SUSPEND
1100 [HIBERNATION_SUSPEND] = "suspend",
1101#endif
1102 [HIBERNATION_TEST_RESUME] = "test_resume",
1103};
1104
1105/*
1106 * /sys/power/disk - Control hibernation mode.
1107 *
1108 * Hibernation can be handled in several ways. There are a few different ways
1109 * to put the system into the sleep state: using the platform driver (e.g. ACPI
1110 * or other hibernation_ops), powering it off or rebooting it (for testing
1111 * mostly).
1112 *
1113 * The sysfs file /sys/power/disk provides an interface for selecting the
1114 * hibernation mode to use. Reading from this file causes the available modes
1115 * to be printed. There are 3 modes that can be supported:
1116 *
1117 * 'platform'
1118 * 'shutdown'
1119 * 'reboot'
1120 *
1121 * If a platform hibernation driver is in use, 'platform' will be supported
1122 * and will be used by default. Otherwise, 'shutdown' will be used by default.
1123 * The selected option (i.e. the one corresponding to the current value of
1124 * hibernation_mode) is enclosed by a square bracket.
1125 *
1126 * To select a given hibernation mode it is necessary to write the mode's
1127 * string representation (as returned by reading from /sys/power/disk) back
1128 * into /sys/power/disk.
1129 */
1130
1131static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
1132 char *buf)
1133{
1134 ssize_t count = 0;
1135 int i;
1136
1137 if (!hibernation_available())
1138 return sysfs_emit(buf, "[disabled]\n");
1139
1140 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
1141 if (!hibernation_modes[i])
1142 continue;
1143 switch (i) {
1144 case HIBERNATION_SHUTDOWN:
1145 case HIBERNATION_REBOOT:
1146#ifdef CONFIG_SUSPEND
1147 case HIBERNATION_SUSPEND:
1148#endif
1149 case HIBERNATION_TEST_RESUME:
1150 break;
1151 case HIBERNATION_PLATFORM:
1152 if (hibernation_ops)
1153 break;
1154 /* not a valid mode, continue with loop */
1155 continue;
1156 }
1157 if (i == hibernation_mode)
1158 count += sysfs_emit_at(buf, count, "[%s] ", hibernation_modes[i]);
1159 else
1160 count += sysfs_emit_at(buf, count, "%s ", hibernation_modes[i]);
1161 }
1162
1163 /* Convert the last space to a newline if needed. */
1164 if (count > 0)
1165 buf[count - 1] = '\n';
1166
1167 return count;
1168}
1169
1170static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
1171 const char *buf, size_t n)
1172{
1173 int mode = HIBERNATION_INVALID;
1174 unsigned int sleep_flags;
1175 int error = 0;
1176 int len;
1177 char *p;
1178 int i;
1179
1180 if (!hibernation_available())
1181 return -EPERM;
1182
1183 p = memchr(buf, '\n', n);
1184 len = p ? p - buf : n;
1185
1186 sleep_flags = lock_system_sleep();
1187 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
1188 if (len == strlen(hibernation_modes[i])
1189 && !strncmp(buf, hibernation_modes[i], len)) {
1190 mode = i;
1191 break;
1192 }
1193 }
1194 if (mode != HIBERNATION_INVALID) {
1195 switch (mode) {
1196 case HIBERNATION_SHUTDOWN:
1197 case HIBERNATION_REBOOT:
1198#ifdef CONFIG_SUSPEND
1199 case HIBERNATION_SUSPEND:
1200#endif
1201 case HIBERNATION_TEST_RESUME:
1202 hibernation_mode = mode;
1203 break;
1204 case HIBERNATION_PLATFORM:
1205 if (hibernation_ops)
1206 hibernation_mode = mode;
1207 else
1208 error = -EINVAL;
1209 }
1210 } else
1211 error = -EINVAL;
1212
1213 if (!error)
1214 pm_pr_dbg("Hibernation mode set to '%s'\n",
1215 hibernation_modes[mode]);
1216 unlock_system_sleep(sleep_flags);
1217 return error ? error : n;
1218}
1219
1220power_attr(disk);
1221
1222static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
1223 char *buf)
1224{
1225 return sysfs_emit(buf, "%d:%d\n", MAJOR(swsusp_resume_device),
1226 MINOR(swsusp_resume_device));
1227}
1228
1229static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
1230 const char *buf, size_t n)
1231{
1232 unsigned int sleep_flags;
1233 int len = n;
1234 char *name;
1235 dev_t dev;
1236 int error;
1237
1238 if (!hibernation_available())
1239 return n;
1240
1241 if (len && buf[len-1] == '\n')
1242 len--;
1243 name = kstrndup(buf, len, GFP_KERNEL);
1244 if (!name)
1245 return -ENOMEM;
1246
1247 error = lookup_bdev(name, &dev);
1248 if (error) {
1249 unsigned maj, min, offset;
1250 char *p, dummy;
1251
1252 error = 0;
1253 if (sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2 ||
1254 sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset,
1255 &dummy) == 3) {
1256 dev = MKDEV(maj, min);
1257 if (maj != MAJOR(dev) || min != MINOR(dev))
1258 error = -EINVAL;
1259 } else {
1260 dev = new_decode_dev(simple_strtoul(name, &p, 16));
1261 if (*p)
1262 error = -EINVAL;
1263 }
1264 }
1265 kfree(name);
1266 if (error)
1267 return error;
1268
1269 sleep_flags = lock_system_sleep();
1270 swsusp_resume_device = dev;
1271 unlock_system_sleep(sleep_flags);
1272
1273 pm_pr_dbg("Configured hibernation resume from disk to %u\n",
1274 swsusp_resume_device);
1275 noresume = 0;
1276 software_resume();
1277 return n;
1278}
1279
1280power_attr(resume);
1281
1282static ssize_t resume_offset_show(struct kobject *kobj,
1283 struct kobj_attribute *attr, char *buf)
1284{
1285 return sysfs_emit(buf, "%llu\n", (unsigned long long)swsusp_resume_block);
1286}
1287
1288static ssize_t resume_offset_store(struct kobject *kobj,
1289 struct kobj_attribute *attr, const char *buf,
1290 size_t n)
1291{
1292 unsigned long long offset;
1293 int rc;
1294
1295 rc = kstrtoull(buf, 0, &offset);
1296 if (rc)
1297 return rc;
1298 swsusp_resume_block = offset;
1299
1300 return n;
1301}
1302
1303power_attr(resume_offset);
1304
1305static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
1306 char *buf)
1307{
1308 return sysfs_emit(buf, "%lu\n", image_size);
1309}
1310
1311static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
1312 const char *buf, size_t n)
1313{
1314 unsigned long size;
1315
1316 if (sscanf(buf, "%lu", &size) == 1) {
1317 image_size = size;
1318 return n;
1319 }
1320
1321 return -EINVAL;
1322}
1323
1324power_attr(image_size);
1325
1326static ssize_t reserved_size_show(struct kobject *kobj,
1327 struct kobj_attribute *attr, char *buf)
1328{
1329 return sysfs_emit(buf, "%lu\n", reserved_size);
1330}
1331
1332static ssize_t reserved_size_store(struct kobject *kobj,
1333 struct kobj_attribute *attr,
1334 const char *buf, size_t n)
1335{
1336 unsigned long size;
1337
1338 if (sscanf(buf, "%lu", &size) == 1) {
1339 reserved_size = size;
1340 return n;
1341 }
1342
1343 return -EINVAL;
1344}
1345
1346power_attr(reserved_size);
1347
1348static struct attribute *g[] = {
1349 &disk_attr.attr,
1350 &resume_offset_attr.attr,
1351 &resume_attr.attr,
1352 &image_size_attr.attr,
1353 &reserved_size_attr.attr,
1354 NULL,
1355};
1356
1357
1358static const struct attribute_group attr_group = {
1359 .attrs = g,
1360};
1361
1362
1363static int __init pm_disk_init(void)
1364{
1365 return sysfs_create_group(power_kobj, &attr_group);
1366}
1367
1368core_initcall(pm_disk_init);
1369
1370
1371static int __init resume_setup(char *str)
1372{
1373 if (noresume)
1374 return 1;
1375
1376 strscpy(resume_file, str);
1377 return 1;
1378}
1379
1380static int __init resume_offset_setup(char *str)
1381{
1382 unsigned long long offset;
1383
1384 if (noresume)
1385 return 1;
1386
1387 if (sscanf(str, "%llu", &offset) == 1)
1388 swsusp_resume_block = offset;
1389
1390 return 1;
1391}
1392
1393static int __init hibernate_setup(char *str)
1394{
1395 if (!strncmp(str, "noresume", 8)) {
1396 noresume = 1;
1397 } else if (!strncmp(str, "nocompress", 10)) {
1398 nocompress = 1;
1399 } else if (!strncmp(str, "no", 2)) {
1400 noresume = 1;
1401 nohibernate = 1;
1402 } else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)
1403 && !strncmp(str, "protect_image", 13)) {
1404 enable_restore_image_protection();
1405 }
1406 return 1;
1407}
1408
1409static int __init noresume_setup(char *str)
1410{
1411 noresume = 1;
1412 return 1;
1413}
1414
1415static int __init resumewait_setup(char *str)
1416{
1417 resume_wait = 1;
1418 return 1;
1419}
1420
1421static int __init resumedelay_setup(char *str)
1422{
1423 int rc = kstrtouint(str, 0, &resume_delay);
1424
1425 if (rc)
1426 pr_warn("resumedelay: bad option string '%s'\n", str);
1427 return 1;
1428}
1429
1430static int __init nohibernate_setup(char *str)
1431{
1432 noresume = 1;
1433 nohibernate = 1;
1434 return 1;
1435}
1436
1437static const char * const comp_alg_enabled[] = {
1438#if IS_ENABLED(CONFIG_CRYPTO_LZO)
1439 COMPRESSION_ALGO_LZO,
1440#endif
1441#if IS_ENABLED(CONFIG_CRYPTO_LZ4)
1442 COMPRESSION_ALGO_LZ4,
1443#endif
1444};
1445
1446static int hibernate_compressor_param_set(const char *compressor,
1447 const struct kernel_param *kp)
1448{
1449 unsigned int sleep_flags;
1450 int index, ret;
1451
1452 sleep_flags = lock_system_sleep();
1453
1454 index = sysfs_match_string(comp_alg_enabled, compressor);
1455 if (index >= 0) {
1456 ret = param_set_copystring(comp_alg_enabled[index], kp);
1457 if (!ret)
1458 strscpy(hib_comp_algo, comp_alg_enabled[index],
1459 sizeof(hib_comp_algo));
1460 } else {
1461 ret = index;
1462 }
1463
1464 unlock_system_sleep(sleep_flags);
1465
1466 if (ret)
1467 pr_debug("Cannot set specified compressor %s\n",
1468 compressor);
1469
1470 return ret;
1471}
1472
1473static const struct kernel_param_ops hibernate_compressor_param_ops = {
1474 .set = hibernate_compressor_param_set,
1475 .get = param_get_string,
1476};
1477
1478static struct kparam_string hibernate_compressor_param_string = {
1479 .maxlen = sizeof(hibernate_compressor),
1480 .string = hibernate_compressor,
1481};
1482
1483module_param_cb(compressor, &hibernate_compressor_param_ops,
1484 &hibernate_compressor_param_string, 0644);
1485MODULE_PARM_DESC(compressor,
1486 "Compression algorithm to be used with hibernation");
1487
1488__setup("noresume", noresume_setup);
1489__setup("resume_offset=", resume_offset_setup);
1490__setup("resume=", resume_setup);
1491__setup("hibernate=", hibernate_setup);
1492__setup("resumewait", resumewait_setup);
1493__setup("resumedelay=", resumedelay_setup);
1494__setup("nohibernate", nohibernate_setup);
1/*
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#include <linux/export.h>
14#include <linux/suspend.h>
15#include <linux/syscalls.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/console.h>
25#include <linux/cpu.h>
26#include <linux/freezer.h>
27#include <linux/gfp.h>
28#include <linux/syscore_ops.h>
29#include <linux/ctype.h>
30#include <linux/genhd.h>
31#include <linux/ktime.h>
32#include <trace/events/power.h>
33
34#include "power.h"
35
36
37static int nocompress;
38static int noresume;
39static int nohibernate;
40static int resume_wait;
41static unsigned int resume_delay;
42static char resume_file[256] = CONFIG_PM_STD_PARTITION;
43dev_t swsusp_resume_device;
44sector_t swsusp_resume_block;
45__visible int in_suspend __nosavedata;
46
47enum {
48 HIBERNATION_INVALID,
49 HIBERNATION_PLATFORM,
50 HIBERNATION_SHUTDOWN,
51 HIBERNATION_REBOOT,
52#ifdef CONFIG_SUSPEND
53 HIBERNATION_SUSPEND,
54#endif
55 /* keep last */
56 __HIBERNATION_AFTER_LAST
57};
58#define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
59#define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
60
61static int hibernation_mode = HIBERNATION_SHUTDOWN;
62
63bool freezer_test_done;
64
65static const struct platform_hibernation_ops *hibernation_ops;
66
67bool hibernation_available(void)
68{
69 return (nohibernate == 0);
70}
71
72/**
73 * hibernation_set_ops - Set the global hibernate operations.
74 * @ops: Hibernation operations to use in subsequent hibernation transitions.
75 */
76void hibernation_set_ops(const struct platform_hibernation_ops *ops)
77{
78 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
79 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
80 && ops->restore_cleanup && ops->leave)) {
81 WARN_ON(1);
82 return;
83 }
84 lock_system_sleep();
85 hibernation_ops = ops;
86 if (ops)
87 hibernation_mode = HIBERNATION_PLATFORM;
88 else if (hibernation_mode == HIBERNATION_PLATFORM)
89 hibernation_mode = HIBERNATION_SHUTDOWN;
90
91 unlock_system_sleep();
92}
93EXPORT_SYMBOL_GPL(hibernation_set_ops);
94
95static bool entering_platform_hibernation;
96
97bool system_entering_hibernation(void)
98{
99 return entering_platform_hibernation;
100}
101EXPORT_SYMBOL(system_entering_hibernation);
102
103#ifdef CONFIG_PM_DEBUG
104static void hibernation_debug_sleep(void)
105{
106 printk(KERN_INFO "hibernation debug: Waiting for 5 seconds.\n");
107 mdelay(5000);
108}
109
110static int hibernation_test(int level)
111{
112 if (pm_test_level == level) {
113 hibernation_debug_sleep();
114 return 1;
115 }
116 return 0;
117}
118#else /* !CONFIG_PM_DEBUG */
119static int hibernation_test(int level) { return 0; }
120#endif /* !CONFIG_PM_DEBUG */
121
122/**
123 * platform_begin - Call platform to start hibernation.
124 * @platform_mode: Whether or not to use the platform driver.
125 */
126static int platform_begin(int platform_mode)
127{
128 return (platform_mode && hibernation_ops) ?
129 hibernation_ops->begin() : 0;
130}
131
132/**
133 * platform_end - Call platform to finish transition to the working state.
134 * @platform_mode: Whether or not to use the platform driver.
135 */
136static void platform_end(int platform_mode)
137{
138 if (platform_mode && hibernation_ops)
139 hibernation_ops->end();
140}
141
142/**
143 * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
144 * @platform_mode: Whether or not to use the platform driver.
145 *
146 * Use the platform driver to prepare the system for creating a hibernate image,
147 * if so configured, and return an error code if that fails.
148 */
149
150static int platform_pre_snapshot(int platform_mode)
151{
152 return (platform_mode && hibernation_ops) ?
153 hibernation_ops->pre_snapshot() : 0;
154}
155
156/**
157 * platform_leave - Call platform to prepare a transition to the working state.
158 * @platform_mode: Whether or not to use the platform driver.
159 *
160 * Use the platform driver prepare to prepare the machine for switching to the
161 * normal mode of operation.
162 *
163 * This routine is called on one CPU with interrupts disabled.
164 */
165static void platform_leave(int platform_mode)
166{
167 if (platform_mode && hibernation_ops)
168 hibernation_ops->leave();
169}
170
171/**
172 * platform_finish - Call platform to switch the system to the working state.
173 * @platform_mode: Whether or not to use the platform driver.
174 *
175 * Use the platform driver to switch the machine to the normal mode of
176 * operation.
177 *
178 * This routine must be called after platform_prepare().
179 */
180static void platform_finish(int platform_mode)
181{
182 if (platform_mode && hibernation_ops)
183 hibernation_ops->finish();
184}
185
186/**
187 * platform_pre_restore - Prepare for hibernate image restoration.
188 * @platform_mode: Whether or not to use the platform driver.
189 *
190 * Use the platform driver to prepare the system for resume from a hibernation
191 * image.
192 *
193 * If the restore fails after this function has been called,
194 * platform_restore_cleanup() must be called.
195 */
196static int platform_pre_restore(int platform_mode)
197{
198 return (platform_mode && hibernation_ops) ?
199 hibernation_ops->pre_restore() : 0;
200}
201
202/**
203 * platform_restore_cleanup - Switch to the working state after failing restore.
204 * @platform_mode: Whether or not to use the platform driver.
205 *
206 * Use the platform driver to switch the system to the normal mode of operation
207 * after a failing restore.
208 *
209 * If platform_pre_restore() has been called before the failing restore, this
210 * function must be called too, regardless of the result of
211 * platform_pre_restore().
212 */
213static void platform_restore_cleanup(int platform_mode)
214{
215 if (platform_mode && hibernation_ops)
216 hibernation_ops->restore_cleanup();
217}
218
219/**
220 * platform_recover - Recover from a failure to suspend devices.
221 * @platform_mode: Whether or not to use the platform driver.
222 */
223static void platform_recover(int platform_mode)
224{
225 if (platform_mode && hibernation_ops && hibernation_ops->recover)
226 hibernation_ops->recover();
227}
228
229/**
230 * swsusp_show_speed - Print time elapsed between two events during hibernation.
231 * @start: Starting event.
232 * @stop: Final event.
233 * @nr_pages: Number of memory pages processed between @start and @stop.
234 * @msg: Additional diagnostic message to print.
235 */
236void swsusp_show_speed(ktime_t start, ktime_t stop,
237 unsigned nr_pages, char *msg)
238{
239 ktime_t diff;
240 u64 elapsed_centisecs64;
241 unsigned int centisecs;
242 unsigned int k;
243 unsigned int kps;
244
245 diff = ktime_sub(stop, start);
246 elapsed_centisecs64 = ktime_divns(diff, 10*NSEC_PER_MSEC);
247 centisecs = elapsed_centisecs64;
248 if (centisecs == 0)
249 centisecs = 1; /* avoid div-by-zero */
250 k = nr_pages * (PAGE_SIZE / 1024);
251 kps = (k * 100) / centisecs;
252 printk(KERN_INFO "PM: %s %u kbytes in %u.%02u seconds (%u.%02u MB/s)\n",
253 msg, k,
254 centisecs / 100, centisecs % 100,
255 kps / 1000, (kps % 1000) / 10);
256}
257
258/**
259 * create_image - Create a hibernation image.
260 * @platform_mode: Whether or not to use the platform driver.
261 *
262 * Execute device drivers' "late" and "noirq" freeze callbacks, create a
263 * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
264 *
265 * Control reappears in this routine after the subsequent restore.
266 */
267static int create_image(int platform_mode)
268{
269 int error;
270
271 error = dpm_suspend_end(PMSG_FREEZE);
272 if (error) {
273 printk(KERN_ERR "PM: Some devices failed to power down, "
274 "aborting hibernation\n");
275 return error;
276 }
277
278 error = platform_pre_snapshot(platform_mode);
279 if (error || hibernation_test(TEST_PLATFORM))
280 goto Platform_finish;
281
282 error = disable_nonboot_cpus();
283 if (error || hibernation_test(TEST_CPUS))
284 goto Enable_cpus;
285
286 local_irq_disable();
287
288 error = syscore_suspend();
289 if (error) {
290 printk(KERN_ERR "PM: Some system devices failed to power down, "
291 "aborting hibernation\n");
292 goto Enable_irqs;
293 }
294
295 if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
296 goto Power_up;
297
298 in_suspend = 1;
299 save_processor_state();
300 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true);
301 error = swsusp_arch_suspend();
302 trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false);
303 if (error)
304 printk(KERN_ERR "PM: Error %d creating hibernation image\n",
305 error);
306 /* Restore control flow magically appears here */
307 restore_processor_state();
308 if (!in_suspend)
309 events_check_enabled = false;
310
311 platform_leave(platform_mode);
312
313 Power_up:
314 syscore_resume();
315
316 Enable_irqs:
317 local_irq_enable();
318
319 Enable_cpus:
320 enable_nonboot_cpus();
321
322 Platform_finish:
323 platform_finish(platform_mode);
324
325 dpm_resume_start(in_suspend ?
326 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
327
328 return error;
329}
330
331/**
332 * hibernation_snapshot - Quiesce devices and create a hibernation image.
333 * @platform_mode: If set, use platform driver to prepare for the transition.
334 *
335 * This routine must be called with pm_mutex held.
336 */
337int hibernation_snapshot(int platform_mode)
338{
339 pm_message_t msg;
340 int error;
341
342 pm_suspend_clear_flags();
343 error = platform_begin(platform_mode);
344 if (error)
345 goto Close;
346
347 /* Preallocate image memory before shutting down devices. */
348 error = hibernate_preallocate_memory();
349 if (error)
350 goto Close;
351
352 error = freeze_kernel_threads();
353 if (error)
354 goto Cleanup;
355
356 if (hibernation_test(TEST_FREEZER)) {
357
358 /*
359 * Indicate to the caller that we are returning due to a
360 * successful freezer test.
361 */
362 freezer_test_done = true;
363 goto Thaw;
364 }
365
366 error = dpm_prepare(PMSG_FREEZE);
367 if (error) {
368 dpm_complete(PMSG_RECOVER);
369 goto Thaw;
370 }
371
372 suspend_console();
373 pm_restrict_gfp_mask();
374
375 error = dpm_suspend(PMSG_FREEZE);
376
377 if (error || hibernation_test(TEST_DEVICES))
378 platform_recover(platform_mode);
379 else
380 error = create_image(platform_mode);
381
382 /*
383 * In the case that we call create_image() above, the control
384 * returns here (1) after the image has been created or the
385 * image creation has failed and (2) after a successful restore.
386 */
387
388 /* We may need to release the preallocated image pages here. */
389 if (error || !in_suspend)
390 swsusp_free();
391
392 msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
393 dpm_resume(msg);
394
395 if (error || !in_suspend)
396 pm_restore_gfp_mask();
397
398 resume_console();
399 dpm_complete(msg);
400
401 Close:
402 platform_end(platform_mode);
403 return error;
404
405 Thaw:
406 thaw_kernel_threads();
407 Cleanup:
408 swsusp_free();
409 goto Close;
410}
411
412/**
413 * resume_target_kernel - Restore system state from a hibernation image.
414 * @platform_mode: Whether or not to use the platform driver.
415 *
416 * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
417 * contents of highmem that have not been restored yet from the image and run
418 * the low-level code that will restore the remaining contents of memory and
419 * switch to the just restored target kernel.
420 */
421static int resume_target_kernel(bool platform_mode)
422{
423 int error;
424
425 error = dpm_suspend_end(PMSG_QUIESCE);
426 if (error) {
427 printk(KERN_ERR "PM: Some devices failed to power down, "
428 "aborting resume\n");
429 return error;
430 }
431
432 error = platform_pre_restore(platform_mode);
433 if (error)
434 goto Cleanup;
435
436 error = disable_nonboot_cpus();
437 if (error)
438 goto Enable_cpus;
439
440 local_irq_disable();
441
442 error = syscore_suspend();
443 if (error)
444 goto Enable_irqs;
445
446 save_processor_state();
447 error = restore_highmem();
448 if (!error) {
449 error = swsusp_arch_resume();
450 /*
451 * The code below is only ever reached in case of a failure.
452 * Otherwise, execution continues at the place where
453 * swsusp_arch_suspend() was called.
454 */
455 BUG_ON(!error);
456 /*
457 * This call to restore_highmem() reverts the changes made by
458 * the previous one.
459 */
460 restore_highmem();
461 }
462 /*
463 * The only reason why swsusp_arch_resume() can fail is memory being
464 * very tight, so we have to free it as soon as we can to avoid
465 * subsequent failures.
466 */
467 swsusp_free();
468 restore_processor_state();
469 touch_softlockup_watchdog();
470
471 syscore_resume();
472
473 Enable_irqs:
474 local_irq_enable();
475
476 Enable_cpus:
477 enable_nonboot_cpus();
478
479 Cleanup:
480 platform_restore_cleanup(platform_mode);
481
482 dpm_resume_start(PMSG_RECOVER);
483
484 return error;
485}
486
487/**
488 * hibernation_restore - Quiesce devices and restore from a hibernation image.
489 * @platform_mode: If set, use platform driver to prepare for the transition.
490 *
491 * This routine must be called with pm_mutex held. If it is successful, control
492 * reappears in the restored target kernel in hibernation_snapshot().
493 */
494int hibernation_restore(int platform_mode)
495{
496 int error;
497
498 pm_prepare_console();
499 suspend_console();
500 pm_restrict_gfp_mask();
501 error = dpm_suspend_start(PMSG_QUIESCE);
502 if (!error) {
503 error = resume_target_kernel(platform_mode);
504 /*
505 * The above should either succeed and jump to the new kernel,
506 * or return with an error. Otherwise things are just
507 * undefined, so let's be paranoid.
508 */
509 BUG_ON(!error);
510 }
511 dpm_resume_end(PMSG_RECOVER);
512 pm_restore_gfp_mask();
513 resume_console();
514 pm_restore_console();
515 return error;
516}
517
518/**
519 * hibernation_platform_enter - Power off the system using the platform driver.
520 */
521int hibernation_platform_enter(void)
522{
523 int error;
524
525 if (!hibernation_ops)
526 return -ENOSYS;
527
528 /*
529 * We have cancelled the power transition by running
530 * hibernation_ops->finish() before saving the image, so we should let
531 * the firmware know that we're going to enter the sleep state after all
532 */
533 error = hibernation_ops->begin();
534 if (error)
535 goto Close;
536
537 entering_platform_hibernation = true;
538 suspend_console();
539 error = dpm_suspend_start(PMSG_HIBERNATE);
540 if (error) {
541 if (hibernation_ops->recover)
542 hibernation_ops->recover();
543 goto Resume_devices;
544 }
545
546 error = dpm_suspend_end(PMSG_HIBERNATE);
547 if (error)
548 goto Resume_devices;
549
550 error = hibernation_ops->prepare();
551 if (error)
552 goto Platform_finish;
553
554 error = disable_nonboot_cpus();
555 if (error)
556 goto Enable_cpus;
557
558 local_irq_disable();
559 syscore_suspend();
560 if (pm_wakeup_pending()) {
561 error = -EAGAIN;
562 goto Power_up;
563 }
564
565 hibernation_ops->enter();
566 /* We should never get here */
567 while (1);
568
569 Power_up:
570 syscore_resume();
571 local_irq_enable();
572
573 Enable_cpus:
574 enable_nonboot_cpus();
575
576 Platform_finish:
577 hibernation_ops->finish();
578
579 dpm_resume_start(PMSG_RESTORE);
580
581 Resume_devices:
582 entering_platform_hibernation = false;
583 dpm_resume_end(PMSG_RESTORE);
584 resume_console();
585
586 Close:
587 hibernation_ops->end();
588
589 return error;
590}
591
592/**
593 * power_down - Shut the machine down for hibernation.
594 *
595 * Use the platform driver, if configured, to put the system into the sleep
596 * state corresponding to hibernation, or try to power it off or reboot,
597 * depending on the value of hibernation_mode.
598 */
599static void power_down(void)
600{
601#ifdef CONFIG_SUSPEND
602 int error;
603#endif
604
605 switch (hibernation_mode) {
606 case HIBERNATION_REBOOT:
607 kernel_restart(NULL);
608 break;
609 case HIBERNATION_PLATFORM:
610 hibernation_platform_enter();
611 case HIBERNATION_SHUTDOWN:
612 if (pm_power_off)
613 kernel_power_off();
614 break;
615#ifdef CONFIG_SUSPEND
616 case HIBERNATION_SUSPEND:
617 error = suspend_devices_and_enter(PM_SUSPEND_MEM);
618 if (error) {
619 if (hibernation_ops)
620 hibernation_mode = HIBERNATION_PLATFORM;
621 else
622 hibernation_mode = HIBERNATION_SHUTDOWN;
623 power_down();
624 }
625 /*
626 * Restore swap signature.
627 */
628 error = swsusp_unmark();
629 if (error)
630 printk(KERN_ERR "PM: Swap will be unusable! "
631 "Try swapon -a.\n");
632 return;
633#endif
634 }
635 kernel_halt();
636 /*
637 * Valid image is on the disk, if we continue we risk serious data
638 * corruption after resume.
639 */
640 printk(KERN_CRIT "PM: Please power down manually\n");
641 while (1)
642 cpu_relax();
643}
644
645/**
646 * hibernate - Carry out system hibernation, including saving the image.
647 */
648int hibernate(void)
649{
650 int error;
651
652 if (!hibernation_available()) {
653 pr_debug("PM: Hibernation not available.\n");
654 return -EPERM;
655 }
656
657 lock_system_sleep();
658 /* The snapshot device should not be opened while we're running */
659 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
660 error = -EBUSY;
661 goto Unlock;
662 }
663
664 pm_prepare_console();
665 error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
666 if (error)
667 goto Exit;
668
669 printk(KERN_INFO "PM: Syncing filesystems ... ");
670 sys_sync();
671 printk("done.\n");
672
673 error = freeze_processes();
674 if (error)
675 goto Exit;
676
677 lock_device_hotplug();
678 /* Allocate memory management structures */
679 error = create_basic_memory_bitmaps();
680 if (error)
681 goto Thaw;
682
683 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
684 if (error || freezer_test_done)
685 goto Free_bitmaps;
686
687 if (in_suspend) {
688 unsigned int flags = 0;
689
690 if (hibernation_mode == HIBERNATION_PLATFORM)
691 flags |= SF_PLATFORM_MODE;
692 if (nocompress)
693 flags |= SF_NOCOMPRESS_MODE;
694 else
695 flags |= SF_CRC32_MODE;
696
697 pr_debug("PM: writing image.\n");
698 error = swsusp_write(flags);
699 swsusp_free();
700 if (!error)
701 power_down();
702 in_suspend = 0;
703 pm_restore_gfp_mask();
704 } else {
705 pr_debug("PM: Image restored successfully.\n");
706 }
707
708 Free_bitmaps:
709 free_basic_memory_bitmaps();
710 Thaw:
711 unlock_device_hotplug();
712 thaw_processes();
713
714 /* Don't bother checking whether freezer_test_done is true */
715 freezer_test_done = false;
716 Exit:
717 pm_notifier_call_chain(PM_POST_HIBERNATION);
718 pm_restore_console();
719 atomic_inc(&snapshot_device_available);
720 Unlock:
721 unlock_system_sleep();
722 return error;
723}
724
725
726/**
727 * software_resume - Resume from a saved hibernation image.
728 *
729 * This routine is called as a late initcall, when all devices have been
730 * discovered and initialized already.
731 *
732 * The image reading code is called to see if there is a hibernation image
733 * available for reading. If that is the case, devices are quiesced and the
734 * contents of memory is restored from the saved image.
735 *
736 * If this is successful, control reappears in the restored target kernel in
737 * hibernation_snapshot() which returns to hibernate(). Otherwise, the routine
738 * attempts to recover gracefully and make the kernel return to the normal mode
739 * of operation.
740 */
741static int software_resume(void)
742{
743 int error;
744 unsigned int flags;
745
746 /*
747 * If the user said "noresume".. bail out early.
748 */
749 if (noresume || !hibernation_available())
750 return 0;
751
752 /*
753 * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
754 * is configured into the kernel. Since the regular hibernate
755 * trigger path is via sysfs which takes a buffer mutex before
756 * calling hibernate functions (which take pm_mutex) this can
757 * cause lockdep to complain about a possible ABBA deadlock
758 * which cannot happen since we're in the boot code here and
759 * sysfs can't be invoked yet. Therefore, we use a subclass
760 * here to avoid lockdep complaining.
761 */
762 mutex_lock_nested(&pm_mutex, SINGLE_DEPTH_NESTING);
763
764 if (swsusp_resume_device)
765 goto Check_image;
766
767 if (!strlen(resume_file)) {
768 error = -ENOENT;
769 goto Unlock;
770 }
771
772 pr_debug("PM: Checking hibernation image partition %s\n", resume_file);
773
774 if (resume_delay) {
775 printk(KERN_INFO "Waiting %dsec before reading resume device...\n",
776 resume_delay);
777 ssleep(resume_delay);
778 }
779
780 /* Check if the device is there */
781 swsusp_resume_device = name_to_dev_t(resume_file);
782
783 /*
784 * name_to_dev_t is ineffective to verify parition if resume_file is in
785 * integer format. (e.g. major:minor)
786 */
787 if (isdigit(resume_file[0]) && resume_wait) {
788 int partno;
789 while (!get_gendisk(swsusp_resume_device, &partno))
790 msleep(10);
791 }
792
793 if (!swsusp_resume_device) {
794 /*
795 * Some device discovery might still be in progress; we need
796 * to wait for this to finish.
797 */
798 wait_for_device_probe();
799
800 if (resume_wait) {
801 while ((swsusp_resume_device = name_to_dev_t(resume_file)) == 0)
802 msleep(10);
803 async_synchronize_full();
804 }
805
806 swsusp_resume_device = name_to_dev_t(resume_file);
807 if (!swsusp_resume_device) {
808 error = -ENODEV;
809 goto Unlock;
810 }
811 }
812
813 Check_image:
814 pr_debug("PM: Hibernation image partition %d:%d present\n",
815 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
816
817 pr_debug("PM: Looking for hibernation image.\n");
818 error = swsusp_check();
819 if (error)
820 goto Unlock;
821
822 /* The snapshot device should not be opened while we're running */
823 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
824 error = -EBUSY;
825 swsusp_close(FMODE_READ);
826 goto Unlock;
827 }
828
829 pm_prepare_console();
830 error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
831 if (error)
832 goto Close_Finish;
833
834 pr_debug("PM: Preparing processes for restore.\n");
835 error = freeze_processes();
836 if (error)
837 goto Close_Finish;
838
839 pr_debug("PM: Loading hibernation image.\n");
840
841 lock_device_hotplug();
842 error = create_basic_memory_bitmaps();
843 if (error)
844 goto Thaw;
845
846 error = swsusp_read(&flags);
847 swsusp_close(FMODE_READ);
848 if (!error)
849 hibernation_restore(flags & SF_PLATFORM_MODE);
850
851 printk(KERN_ERR "PM: Failed to load hibernation image, recovering.\n");
852 swsusp_free();
853 free_basic_memory_bitmaps();
854 Thaw:
855 unlock_device_hotplug();
856 thaw_processes();
857 Finish:
858 pm_notifier_call_chain(PM_POST_RESTORE);
859 pm_restore_console();
860 atomic_inc(&snapshot_device_available);
861 /* For success case, the suspend path will release the lock */
862 Unlock:
863 mutex_unlock(&pm_mutex);
864 pr_debug("PM: Hibernation image not present or could not be loaded.\n");
865 return error;
866 Close_Finish:
867 swsusp_close(FMODE_READ);
868 goto Finish;
869}
870
871late_initcall_sync(software_resume);
872
873
874static const char * const hibernation_modes[] = {
875 [HIBERNATION_PLATFORM] = "platform",
876 [HIBERNATION_SHUTDOWN] = "shutdown",
877 [HIBERNATION_REBOOT] = "reboot",
878#ifdef CONFIG_SUSPEND
879 [HIBERNATION_SUSPEND] = "suspend",
880#endif
881};
882
883/*
884 * /sys/power/disk - Control hibernation mode.
885 *
886 * Hibernation can be handled in several ways. There are a few different ways
887 * to put the system into the sleep state: using the platform driver (e.g. ACPI
888 * or other hibernation_ops), powering it off or rebooting it (for testing
889 * mostly).
890 *
891 * The sysfs file /sys/power/disk provides an interface for selecting the
892 * hibernation mode to use. Reading from this file causes the available modes
893 * to be printed. There are 3 modes that can be supported:
894 *
895 * 'platform'
896 * 'shutdown'
897 * 'reboot'
898 *
899 * If a platform hibernation driver is in use, 'platform' will be supported
900 * and will be used by default. Otherwise, 'shutdown' will be used by default.
901 * The selected option (i.e. the one corresponding to the current value of
902 * hibernation_mode) is enclosed by a square bracket.
903 *
904 * To select a given hibernation mode it is necessary to write the mode's
905 * string representation (as returned by reading from /sys/power/disk) back
906 * into /sys/power/disk.
907 */
908
909static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
910 char *buf)
911{
912 int i;
913 char *start = buf;
914
915 if (!hibernation_available())
916 return sprintf(buf, "[disabled]\n");
917
918 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
919 if (!hibernation_modes[i])
920 continue;
921 switch (i) {
922 case HIBERNATION_SHUTDOWN:
923 case HIBERNATION_REBOOT:
924#ifdef CONFIG_SUSPEND
925 case HIBERNATION_SUSPEND:
926#endif
927 break;
928 case HIBERNATION_PLATFORM:
929 if (hibernation_ops)
930 break;
931 /* not a valid mode, continue with loop */
932 continue;
933 }
934 if (i == hibernation_mode)
935 buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
936 else
937 buf += sprintf(buf, "%s ", hibernation_modes[i]);
938 }
939 buf += sprintf(buf, "\n");
940 return buf-start;
941}
942
943static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
944 const char *buf, size_t n)
945{
946 int error = 0;
947 int i;
948 int len;
949 char *p;
950 int mode = HIBERNATION_INVALID;
951
952 if (!hibernation_available())
953 return -EPERM;
954
955 p = memchr(buf, '\n', n);
956 len = p ? p - buf : n;
957
958 lock_system_sleep();
959 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
960 if (len == strlen(hibernation_modes[i])
961 && !strncmp(buf, hibernation_modes[i], len)) {
962 mode = i;
963 break;
964 }
965 }
966 if (mode != HIBERNATION_INVALID) {
967 switch (mode) {
968 case HIBERNATION_SHUTDOWN:
969 case HIBERNATION_REBOOT:
970#ifdef CONFIG_SUSPEND
971 case HIBERNATION_SUSPEND:
972#endif
973 hibernation_mode = mode;
974 break;
975 case HIBERNATION_PLATFORM:
976 if (hibernation_ops)
977 hibernation_mode = mode;
978 else
979 error = -EINVAL;
980 }
981 } else
982 error = -EINVAL;
983
984 if (!error)
985 pr_debug("PM: Hibernation mode set to '%s'\n",
986 hibernation_modes[mode]);
987 unlock_system_sleep();
988 return error ? error : n;
989}
990
991power_attr(disk);
992
993static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
994 char *buf)
995{
996 return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
997 MINOR(swsusp_resume_device));
998}
999
1000static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
1001 const char *buf, size_t n)
1002{
1003 dev_t res;
1004 int len = n;
1005 char *name;
1006
1007 if (len && buf[len-1] == '\n')
1008 len--;
1009 name = kstrndup(buf, len, GFP_KERNEL);
1010 if (!name)
1011 return -ENOMEM;
1012
1013 res = name_to_dev_t(name);
1014 kfree(name);
1015 if (!res)
1016 return -EINVAL;
1017
1018 lock_system_sleep();
1019 swsusp_resume_device = res;
1020 unlock_system_sleep();
1021 printk(KERN_INFO "PM: Starting manual resume from disk\n");
1022 noresume = 0;
1023 software_resume();
1024 return n;
1025}
1026
1027power_attr(resume);
1028
1029static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
1030 char *buf)
1031{
1032 return sprintf(buf, "%lu\n", image_size);
1033}
1034
1035static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
1036 const char *buf, size_t n)
1037{
1038 unsigned long size;
1039
1040 if (sscanf(buf, "%lu", &size) == 1) {
1041 image_size = size;
1042 return n;
1043 }
1044
1045 return -EINVAL;
1046}
1047
1048power_attr(image_size);
1049
1050static ssize_t reserved_size_show(struct kobject *kobj,
1051 struct kobj_attribute *attr, char *buf)
1052{
1053 return sprintf(buf, "%lu\n", reserved_size);
1054}
1055
1056static ssize_t reserved_size_store(struct kobject *kobj,
1057 struct kobj_attribute *attr,
1058 const char *buf, size_t n)
1059{
1060 unsigned long size;
1061
1062 if (sscanf(buf, "%lu", &size) == 1) {
1063 reserved_size = size;
1064 return n;
1065 }
1066
1067 return -EINVAL;
1068}
1069
1070power_attr(reserved_size);
1071
1072static struct attribute * g[] = {
1073 &disk_attr.attr,
1074 &resume_attr.attr,
1075 &image_size_attr.attr,
1076 &reserved_size_attr.attr,
1077 NULL,
1078};
1079
1080
1081static struct attribute_group attr_group = {
1082 .attrs = g,
1083};
1084
1085
1086static int __init pm_disk_init(void)
1087{
1088 return sysfs_create_group(power_kobj, &attr_group);
1089}
1090
1091core_initcall(pm_disk_init);
1092
1093
1094static int __init resume_setup(char *str)
1095{
1096 if (noresume)
1097 return 1;
1098
1099 strncpy( resume_file, str, 255 );
1100 return 1;
1101}
1102
1103static int __init resume_offset_setup(char *str)
1104{
1105 unsigned long long offset;
1106
1107 if (noresume)
1108 return 1;
1109
1110 if (sscanf(str, "%llu", &offset) == 1)
1111 swsusp_resume_block = offset;
1112
1113 return 1;
1114}
1115
1116static int __init hibernate_setup(char *str)
1117{
1118 if (!strncmp(str, "noresume", 8))
1119 noresume = 1;
1120 else if (!strncmp(str, "nocompress", 10))
1121 nocompress = 1;
1122 else if (!strncmp(str, "no", 2)) {
1123 noresume = 1;
1124 nohibernate = 1;
1125 }
1126 return 1;
1127}
1128
1129static int __init noresume_setup(char *str)
1130{
1131 noresume = 1;
1132 return 1;
1133}
1134
1135static int __init resumewait_setup(char *str)
1136{
1137 resume_wait = 1;
1138 return 1;
1139}
1140
1141static int __init resumedelay_setup(char *str)
1142{
1143 int rc = kstrtouint(str, 0, &resume_delay);
1144
1145 if (rc)
1146 return rc;
1147 return 1;
1148}
1149
1150static int __init nohibernate_setup(char *str)
1151{
1152 noresume = 1;
1153 nohibernate = 1;
1154 return 1;
1155}
1156
1157static int __init kaslr_nohibernate_setup(char *str)
1158{
1159 return nohibernate_setup(str);
1160}
1161
1162static int __init page_poison_nohibernate_setup(char *str)
1163{
1164#ifdef CONFIG_PAGE_POISONING_ZERO
1165 /*
1166 * The zeroing option for page poison skips the checks on alloc.
1167 * since hibernation doesn't save free pages there's no way to
1168 * guarantee the pages will still be zeroed.
1169 */
1170 if (!strcmp(str, "on")) {
1171 pr_info("Disabling hibernation due to page poisoning\n");
1172 return nohibernate_setup(str);
1173 }
1174#endif
1175 return 1;
1176}
1177
1178__setup("noresume", noresume_setup);
1179__setup("resume_offset=", resume_offset_setup);
1180__setup("resume=", resume_setup);
1181__setup("hibernate=", hibernate_setup);
1182__setup("resumewait", resumewait_setup);
1183__setup("resumedelay=", resumedelay_setup);
1184__setup("nohibernate", nohibernate_setup);
1185__setup("kaslr", kaslr_nohibernate_setup);
1186__setup("page_poison=", page_poison_nohibernate_setup);