2 * kernel/power/hibernate.c - Hibernation (a.k.a suspend-to-disk) support.
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.
9 * This file is released under the GPLv2.
12 #include <linux/suspend.h>
13 #include <linux/syscalls.h>
14 #include <linux/reboot.h>
15 #include <linux/string.h>
16 #include <linux/device.h>
17 #include <linux/kmod.h>
18 #include <linux/delay.h>
20 #include <linux/mount.h>
22 #include <linux/console.h>
23 #include <linux/cpu.h>
24 #include <linux/freezer.h>
25 #include <linux/gfp.h>
26 #include <scsi/scsi_scan.h>
27 #include <asm/suspend.h>
32 static int noresume
= 0;
33 static char resume_file
[256] = CONFIG_PM_STD_PARTITION
;
34 dev_t swsusp_resume_device
;
35 sector_t swsusp_resume_block
;
36 int in_suspend __nosavedata
= 0;
46 __HIBERNATION_AFTER_LAST
48 #define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
49 #define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
51 static int hibernation_mode
= HIBERNATION_SHUTDOWN
;
53 static struct platform_hibernation_ops
*hibernation_ops
;
56 * hibernation_set_ops - set the global hibernate operations
57 * @ops: the hibernation operations to use in subsequent hibernation transitions
60 void hibernation_set_ops(struct platform_hibernation_ops
*ops
)
62 if (ops
&& !(ops
->begin
&& ops
->end
&& ops
->pre_snapshot
63 && ops
->prepare
&& ops
->finish
&& ops
->enter
&& ops
->pre_restore
64 && ops
->restore_cleanup
)) {
68 mutex_lock(&pm_mutex
);
69 hibernation_ops
= ops
;
71 hibernation_mode
= HIBERNATION_PLATFORM
;
72 else if (hibernation_mode
== HIBERNATION_PLATFORM
)
73 hibernation_mode
= HIBERNATION_SHUTDOWN
;
75 mutex_unlock(&pm_mutex
);
78 static bool entering_platform_hibernation
;
80 bool system_entering_hibernation(void)
82 return entering_platform_hibernation
;
84 EXPORT_SYMBOL(system_entering_hibernation
);
86 #ifdef CONFIG_PM_DEBUG
87 static void hibernation_debug_sleep(void)
89 printk(KERN_INFO
"hibernation debug: Waiting for 5 seconds.\n");
93 static int hibernation_testmode(int mode
)
95 if (hibernation_mode
== mode
) {
96 hibernation_debug_sleep();
102 static int hibernation_test(int level
)
104 if (pm_test_level
== level
) {
105 hibernation_debug_sleep();
110 #else /* !CONFIG_PM_DEBUG */
111 static int hibernation_testmode(int mode
) { return 0; }
112 static int hibernation_test(int level
) { return 0; }
113 #endif /* !CONFIG_PM_DEBUG */
116 * platform_begin - tell the platform driver that we're starting
120 static int platform_begin(int platform_mode
)
122 return (platform_mode
&& hibernation_ops
) ?
123 hibernation_ops
->begin() : 0;
127 * platform_end - tell the platform driver that we've entered the
131 static void platform_end(int platform_mode
)
133 if (platform_mode
&& hibernation_ops
)
134 hibernation_ops
->end();
138 * platform_pre_snapshot - prepare the machine for hibernation using the
139 * platform driver if so configured and return an error code if it fails
142 static int platform_pre_snapshot(int platform_mode
)
144 return (platform_mode
&& hibernation_ops
) ?
145 hibernation_ops
->pre_snapshot() : 0;
149 * platform_leave - prepare the machine for switching to the normal mode
150 * of operation using the platform driver (called with interrupts disabled)
153 static void platform_leave(int platform_mode
)
155 if (platform_mode
&& hibernation_ops
)
156 hibernation_ops
->leave();
160 * platform_finish - switch the machine to the normal mode of operation
161 * using the platform driver (must be called after platform_prepare())
164 static void platform_finish(int platform_mode
)
166 if (platform_mode
&& hibernation_ops
)
167 hibernation_ops
->finish();
171 * platform_pre_restore - prepare the platform for the restoration from a
172 * hibernation image. If the restore fails after this function has been
173 * called, platform_restore_cleanup() must be called.
176 static int platform_pre_restore(int platform_mode
)
178 return (platform_mode
&& hibernation_ops
) ?
179 hibernation_ops
->pre_restore() : 0;
183 * platform_restore_cleanup - switch the platform to the normal mode of
184 * operation after a failing restore. If platform_pre_restore() has been
185 * called before the failing restore, this function must be called too,
186 * regardless of the result of platform_pre_restore().
189 static void platform_restore_cleanup(int platform_mode
)
191 if (platform_mode
&& hibernation_ops
)
192 hibernation_ops
->restore_cleanup();
196 * platform_recover - recover the platform from a failure to suspend
200 static void platform_recover(int platform_mode
)
202 if (platform_mode
&& hibernation_ops
&& hibernation_ops
->recover
)
203 hibernation_ops
->recover();
207 * swsusp_show_speed - print the time elapsed between two events.
208 * @start: Starting event.
209 * @stop: Final event.
210 * @nr_pages - number of pages processed between @start and @stop
211 * @msg - introductory message to print
214 void swsusp_show_speed(struct timeval
*start
, struct timeval
*stop
,
215 unsigned nr_pages
, char *msg
)
217 s64 elapsed_centisecs64
;
222 elapsed_centisecs64
= timeval_to_ns(stop
) - timeval_to_ns(start
);
223 do_div(elapsed_centisecs64
, NSEC_PER_SEC
/ 100);
224 centisecs
= elapsed_centisecs64
;
226 centisecs
= 1; /* avoid div-by-zero */
227 k
= nr_pages
* (PAGE_SIZE
/ 1024);
228 kps
= (k
* 100) / centisecs
;
229 printk(KERN_INFO
"PM: %s %d kbytes in %d.%02d seconds (%d.%02d MB/s)\n",
231 centisecs
/ 100, centisecs
% 100,
232 kps
/ 1000, (kps
% 1000) / 10);
236 * create_image - freeze devices that need to be frozen with interrupts
237 * off, create the hibernation image and thaw those devices. Control
238 * reappears in this routine after a restore.
241 static int create_image(int platform_mode
)
245 error
= arch_prepare_suspend();
249 /* At this point, dpm_suspend_start() has been called, but *not*
250 * dpm_suspend_noirq(). We *must* call dpm_suspend_noirq() now.
251 * Otherwise, drivers for some devices (e.g. interrupt controllers)
252 * become desynchronized with the actual state of the hardware
253 * at resume time, and evil weirdness ensues.
255 error
= dpm_suspend_noirq(PMSG_FREEZE
);
257 printk(KERN_ERR
"PM: Some devices failed to power down, "
258 "aborting hibernation\n");
262 error
= platform_pre_snapshot(platform_mode
);
263 if (error
|| hibernation_test(TEST_PLATFORM
))
264 goto Platform_finish
;
266 error
= disable_nonboot_cpus();
267 if (error
|| hibernation_test(TEST_CPUS
)
268 || hibernation_testmode(HIBERNATION_TEST
))
273 error
= sysdev_suspend(PMSG_FREEZE
);
275 printk(KERN_ERR
"PM: Some system devices failed to power down, "
276 "aborting hibernation\n");
280 if (hibernation_test(TEST_CORE
) || !pm_check_wakeup_events())
284 save_processor_state();
285 error
= swsusp_arch_suspend();
287 printk(KERN_ERR
"PM: Error %d creating hibernation image\n",
289 /* Restore control flow magically appears here */
290 restore_processor_state();
292 events_check_enabled
= false;
293 platform_leave(platform_mode
);
298 /* NOTE: dpm_resume_noirq() is just a resume() for devices
299 * that suspended with irqs off ... no overall powerup.
306 enable_nonboot_cpus();
309 platform_finish(platform_mode
);
311 dpm_resume_noirq(in_suspend
?
312 (error
? PMSG_RECOVER
: PMSG_THAW
) : PMSG_RESTORE
);
318 * hibernation_snapshot - quiesce devices and create the hibernation
320 * @platform_mode - if set, use the platform driver, if available, to
321 * prepare the platform firmware for the power transition.
323 * Must be called with pm_mutex held
326 int hibernation_snapshot(int platform_mode
)
330 error
= platform_begin(platform_mode
);
334 /* Preallocate image memory before shutting down devices. */
335 error
= hibernate_preallocate_memory();
340 pm_restrict_gfp_mask();
341 error
= dpm_suspend_start(PMSG_FREEZE
);
343 goto Recover_platform
;
345 if (hibernation_test(TEST_DEVICES
))
346 goto Recover_platform
;
348 error
= create_image(platform_mode
);
350 * Control returns here (1) after the image has been created or the
351 * image creation has failed and (2) after a successful restore.
355 /* We may need to release the preallocated image pages here. */
356 if (error
|| !in_suspend
)
359 dpm_resume_end(in_suspend
?
360 (error
? PMSG_RECOVER
: PMSG_THAW
) : PMSG_RESTORE
);
362 if (error
|| !in_suspend
)
363 pm_restore_gfp_mask();
367 platform_end(platform_mode
);
371 platform_recover(platform_mode
);
376 * resume_target_kernel - prepare devices that need to be suspended with
377 * interrupts off, restore the contents of highmem that have not been
378 * restored yet from the image and run the low level code that will restore
379 * the remaining contents of memory and switch to the just restored target
383 static int resume_target_kernel(bool platform_mode
)
387 error
= dpm_suspend_noirq(PMSG_QUIESCE
);
389 printk(KERN_ERR
"PM: Some devices failed to power down, "
390 "aborting resume\n");
394 error
= platform_pre_restore(platform_mode
);
398 error
= disable_nonboot_cpus();
404 error
= sysdev_suspend(PMSG_QUIESCE
);
408 /* We'll ignore saved state, but this gets preempt count (etc) right */
409 save_processor_state();
410 error
= restore_highmem();
412 error
= swsusp_arch_resume();
414 * The code below is only ever reached in case of a failure.
415 * Otherwise execution continues at place where
416 * swsusp_arch_suspend() was called
419 /* This call to restore_highmem() undos the previous one */
423 * The only reason why swsusp_arch_resume() can fail is memory being
424 * very tight, so we have to free it as soon as we can to avoid
425 * subsequent failures
428 restore_processor_state();
429 touch_softlockup_watchdog();
437 enable_nonboot_cpus();
440 platform_restore_cleanup(platform_mode
);
442 dpm_resume_noirq(PMSG_RECOVER
);
448 * hibernation_restore - quiesce devices and restore the hibernation
449 * snapshot image. If successful, control returns in hibernation_snaphot()
450 * @platform_mode - if set, use the platform driver, if available, to
451 * prepare the platform firmware for the transition.
453 * Must be called with pm_mutex held
456 int hibernation_restore(int platform_mode
)
460 pm_prepare_console();
462 pm_restrict_gfp_mask();
463 error
= dpm_suspend_start(PMSG_QUIESCE
);
465 error
= resume_target_kernel(platform_mode
);
466 dpm_resume_end(PMSG_RECOVER
);
468 pm_restore_gfp_mask();
470 pm_restore_console();
475 * hibernation_platform_enter - enter the hibernation state using the
476 * platform driver (if available)
479 int hibernation_platform_enter(void)
483 if (!hibernation_ops
)
487 * We have cancelled the power transition by running
488 * hibernation_ops->finish() before saving the image, so we should let
489 * the firmware know that we're going to enter the sleep state after all
491 error
= hibernation_ops
->begin();
495 entering_platform_hibernation
= true;
497 error
= dpm_suspend_start(PMSG_HIBERNATE
);
499 if (hibernation_ops
->recover
)
500 hibernation_ops
->recover();
504 error
= dpm_suspend_noirq(PMSG_HIBERNATE
);
508 error
= hibernation_ops
->prepare();
510 goto Platform_finish
;
512 error
= disable_nonboot_cpus();
514 goto Platform_finish
;
517 sysdev_suspend(PMSG_HIBERNATE
);
518 if (!pm_check_wakeup_events()) {
523 hibernation_ops
->enter();
524 /* We should never get here */
530 enable_nonboot_cpus();
533 hibernation_ops
->finish();
535 dpm_resume_noirq(PMSG_RESTORE
);
538 entering_platform_hibernation
= false;
539 dpm_resume_end(PMSG_RESTORE
);
543 hibernation_ops
->end();
549 * power_down - Shut the machine down for hibernation.
551 * Use the platform driver, if configured so; otherwise try
552 * to power off or reboot.
555 static void power_down(void)
557 switch (hibernation_mode
) {
558 case HIBERNATION_TEST
:
559 case HIBERNATION_TESTPROC
:
561 case HIBERNATION_REBOOT
:
562 kernel_restart(NULL
);
564 case HIBERNATION_PLATFORM
:
565 hibernation_platform_enter();
566 case HIBERNATION_SHUTDOWN
:
572 * Valid image is on the disk, if we continue we risk serious data
573 * corruption after resume.
575 printk(KERN_CRIT
"PM: Please power down manually\n");
579 static int prepare_processes(void)
583 if (freeze_processes()) {
591 * hibernate - The granpappy of the built-in hibernation management
598 mutex_lock(&pm_mutex
);
599 /* The snapshot device should not be opened while we're running */
600 if (!atomic_add_unless(&snapshot_device_available
, -1, 0)) {
605 pm_prepare_console();
606 error
= pm_notifier_call_chain(PM_HIBERNATION_PREPARE
);
610 error
= usermodehelper_disable();
614 /* Allocate memory management structures */
615 error
= create_basic_memory_bitmaps();
619 printk(KERN_INFO
"PM: Syncing filesystems ... ");
623 error
= prepare_processes();
627 if (hibernation_test(TEST_FREEZER
))
630 if (hibernation_testmode(HIBERNATION_TESTPROC
))
633 error
= hibernation_snapshot(hibernation_mode
== HIBERNATION_PLATFORM
);
638 unsigned int flags
= 0;
640 if (hibernation_mode
== HIBERNATION_PLATFORM
)
641 flags
|= SF_PLATFORM_MODE
;
642 pr_debug("PM: writing image.\n");
643 error
= swsusp_write(flags
);
647 pm_restore_gfp_mask();
649 pr_debug("PM: Image restored successfully.\n");
655 free_basic_memory_bitmaps();
656 usermodehelper_enable();
658 pm_notifier_call_chain(PM_POST_HIBERNATION
);
659 pm_restore_console();
660 atomic_inc(&snapshot_device_available
);
662 mutex_unlock(&pm_mutex
);
668 * software_resume - Resume from a saved image.
670 * Called as a late_initcall (so all devices are discovered and
671 * initialized), we call swsusp to see if we have a saved image or not.
672 * If so, we quiesce devices, the restore the saved image. We will
673 * return above (in hibernate() ) if everything goes well.
674 * Otherwise, we fail gracefully and return to the normally
679 static int software_resume(void)
685 * If the user said "noresume".. bail out early.
691 * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
692 * is configured into the kernel. Since the regular hibernate
693 * trigger path is via sysfs which takes a buffer mutex before
694 * calling hibernate functions (which take pm_mutex) this can
695 * cause lockdep to complain about a possible ABBA deadlock
696 * which cannot happen since we're in the boot code here and
697 * sysfs can't be invoked yet. Therefore, we use a subclass
698 * here to avoid lockdep complaining.
700 mutex_lock_nested(&pm_mutex
, SINGLE_DEPTH_NESTING
);
702 if (swsusp_resume_device
)
705 if (!strlen(resume_file
)) {
710 pr_debug("PM: Checking image partition %s\n", resume_file
);
712 /* Check if the device is there */
713 swsusp_resume_device
= name_to_dev_t(resume_file
);
714 if (!swsusp_resume_device
) {
716 * Some device discovery might still be in progress; we need
717 * to wait for this to finish.
719 wait_for_device_probe();
721 * We can't depend on SCSI devices being available after loading
722 * one of their modules until scsi_complete_async_scans() is
723 * called and the resume device usually is a SCSI one.
725 scsi_complete_async_scans();
727 swsusp_resume_device
= name_to_dev_t(resume_file
);
728 if (!swsusp_resume_device
) {
735 pr_debug("PM: Resume from partition %d:%d\n",
736 MAJOR(swsusp_resume_device
), MINOR(swsusp_resume_device
));
738 pr_debug("PM: Checking hibernation image.\n");
739 error
= swsusp_check();
743 /* The snapshot device should not be opened while we're running */
744 if (!atomic_add_unless(&snapshot_device_available
, -1, 0)) {
746 swsusp_close(FMODE_READ
);
750 pm_prepare_console();
751 error
= pm_notifier_call_chain(PM_RESTORE_PREPARE
);
755 error
= usermodehelper_disable();
759 error
= create_basic_memory_bitmaps();
763 pr_debug("PM: Preparing processes for restore.\n");
764 error
= prepare_processes();
766 swsusp_close(FMODE_READ
);
770 pr_debug("PM: Reading hibernation image.\n");
772 error
= swsusp_read(&flags
);
773 swsusp_close(FMODE_READ
);
775 hibernation_restore(flags
& SF_PLATFORM_MODE
);
777 printk(KERN_ERR
"PM: Restore failed, recovering.\n");
781 free_basic_memory_bitmaps();
782 usermodehelper_enable();
784 pm_notifier_call_chain(PM_POST_RESTORE
);
785 pm_restore_console();
786 atomic_inc(&snapshot_device_available
);
787 /* For success case, the suspend path will release the lock */
789 mutex_unlock(&pm_mutex
);
790 pr_debug("PM: Resume from disk failed.\n");
793 swsusp_close(FMODE_READ
);
797 late_initcall(software_resume
);
800 static const char * const hibernation_modes
[] = {
801 [HIBERNATION_PLATFORM
] = "platform",
802 [HIBERNATION_SHUTDOWN
] = "shutdown",
803 [HIBERNATION_REBOOT
] = "reboot",
804 [HIBERNATION_TEST
] = "test",
805 [HIBERNATION_TESTPROC
] = "testproc",
809 * disk - Control hibernation mode
811 * Suspend-to-disk can be handled in several ways. We have a few options
812 * for putting the system to sleep - using the platform driver (e.g. ACPI
813 * or other hibernation_ops), powering off the system or rebooting the
814 * system (for testing) as well as the two test modes.
816 * The system can support 'platform', and that is known a priori (and
817 * encoded by the presence of hibernation_ops). However, the user may
818 * choose 'shutdown' or 'reboot' as alternatives, as well as one fo the
819 * test modes, 'test' or 'testproc'.
821 * show() will display what the mode is currently set to.
822 * store() will accept one of
830 * It will only change to 'platform' if the system
831 * supports it (as determined by having hibernation_ops).
834 static ssize_t
disk_show(struct kobject
*kobj
, struct kobj_attribute
*attr
,
840 for (i
= HIBERNATION_FIRST
; i
<= HIBERNATION_MAX
; i
++) {
841 if (!hibernation_modes
[i
])
844 case HIBERNATION_SHUTDOWN
:
845 case HIBERNATION_REBOOT
:
846 case HIBERNATION_TEST
:
847 case HIBERNATION_TESTPROC
:
849 case HIBERNATION_PLATFORM
:
852 /* not a valid mode, continue with loop */
855 if (i
== hibernation_mode
)
856 buf
+= sprintf(buf
, "[%s] ", hibernation_modes
[i
]);
858 buf
+= sprintf(buf
, "%s ", hibernation_modes
[i
]);
860 buf
+= sprintf(buf
, "\n");
865 static ssize_t
disk_store(struct kobject
*kobj
, struct kobj_attribute
*attr
,
866 const char *buf
, size_t n
)
872 int mode
= HIBERNATION_INVALID
;
874 p
= memchr(buf
, '\n', n
);
875 len
= p
? p
- buf
: n
;
877 mutex_lock(&pm_mutex
);
878 for (i
= HIBERNATION_FIRST
; i
<= HIBERNATION_MAX
; i
++) {
879 if (len
== strlen(hibernation_modes
[i
])
880 && !strncmp(buf
, hibernation_modes
[i
], len
)) {
885 if (mode
!= HIBERNATION_INVALID
) {
887 case HIBERNATION_SHUTDOWN
:
888 case HIBERNATION_REBOOT
:
889 case HIBERNATION_TEST
:
890 case HIBERNATION_TESTPROC
:
891 hibernation_mode
= mode
;
893 case HIBERNATION_PLATFORM
:
895 hibernation_mode
= mode
;
903 pr_debug("PM: Hibernation mode set to '%s'\n",
904 hibernation_modes
[mode
]);
905 mutex_unlock(&pm_mutex
);
906 return error
? error
: n
;
911 static ssize_t
resume_show(struct kobject
*kobj
, struct kobj_attribute
*attr
,
914 return sprintf(buf
,"%d:%d\n", MAJOR(swsusp_resume_device
),
915 MINOR(swsusp_resume_device
));
918 static ssize_t
resume_store(struct kobject
*kobj
, struct kobj_attribute
*attr
,
919 const char *buf
, size_t n
)
921 unsigned int maj
, min
;
925 if (sscanf(buf
, "%u:%u", &maj
, &min
) != 2)
928 res
= MKDEV(maj
,min
);
929 if (maj
!= MAJOR(res
) || min
!= MINOR(res
))
932 mutex_lock(&pm_mutex
);
933 swsusp_resume_device
= res
;
934 mutex_unlock(&pm_mutex
);
935 printk(KERN_INFO
"PM: Starting manual resume from disk\n");
945 static ssize_t
image_size_show(struct kobject
*kobj
, struct kobj_attribute
*attr
,
948 return sprintf(buf
, "%lu\n", image_size
);
951 static ssize_t
image_size_store(struct kobject
*kobj
, struct kobj_attribute
*attr
,
952 const char *buf
, size_t n
)
956 if (sscanf(buf
, "%lu", &size
) == 1) {
964 power_attr(image_size
);
966 static struct attribute
* g
[] = {
969 &image_size_attr
.attr
,
974 static struct attribute_group attr_group
= {
979 static int __init
pm_disk_init(void)
981 return sysfs_create_group(power_kobj
, &attr_group
);
984 core_initcall(pm_disk_init
);
987 static int __init
resume_setup(char *str
)
992 strncpy( resume_file
, str
, 255 );
996 static int __init
resume_offset_setup(char *str
)
998 unsigned long long offset
;
1003 if (sscanf(str
, "%llu", &offset
) == 1)
1004 swsusp_resume_block
= offset
;
1009 static int __init
noresume_setup(char *str
)
1015 __setup("noresume", noresume_setup
);
1016 __setup("resume_offset=", resume_offset_setup
);
1017 __setup("resume=", resume_setup
);