2 * kernel/power/disk.c - 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@suse.cz>
8 * 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/delay.h>
19 #include <linux/mount.h>
21 #include <linux/console.h>
22 #include <linux/cpu.h>
23 #include <linux/freezer.h>
28 static int noresume
= 0;
29 char resume_file
[256] = CONFIG_PM_STD_PARTITION
;
30 dev_t swsusp_resume_device
;
31 sector_t swsusp_resume_block
;
34 * platform_prepare - prepare the machine for hibernation using the
35 * platform driver if so configured and return an error code if it fails
38 static inline int platform_prepare(void)
42 if (pm_disk_mode
== PM_DISK_PLATFORM
) {
43 if (pm_ops
&& pm_ops
->prepare
)
44 error
= pm_ops
->prepare(PM_SUSPEND_DISK
);
50 * power_down - Shut machine down for hibernate.
51 * @mode: Suspend-to-disk mode
53 * Use the platform driver, if configured so, and return gracefully if it
55 * Otherwise, try to power off and reboot. If they fail, halt the machine,
56 * there ain't no turning back.
59 static void power_down(suspend_disk_method_t mode
)
64 case PM_DISK_PLATFORM
:
65 kernel_shutdown_prepare(SYSTEM_SUSPEND_DISK
);
66 error
= pm_ops
->enter(PM_SUSPEND_DISK
);
68 case PM_DISK_SHUTDOWN
:
76 /* Valid image is on the disk, if we continue we risk serious data corruption
78 printk(KERN_CRIT
"Please power me down manually\n");
82 static inline void platform_finish(void)
84 if (pm_disk_mode
== PM_DISK_PLATFORM
) {
85 if (pm_ops
&& pm_ops
->finish
)
86 pm_ops
->finish(PM_SUSPEND_DISK
);
90 static int prepare_processes(void)
96 error
= disable_nonboot_cpus();
100 if (freeze_processes()) {
105 if (pm_disk_mode
== PM_DISK_TESTPROC
) {
106 printk("swsusp debug: Waiting for 5 seconds.\n");
111 error
= platform_prepare();
115 /* Free memory before shutting down devices. */
116 if (!(error
= swsusp_shrink_memory()))
123 enable_nonboot_cpus();
124 pm_restore_console();
128 static void unprepare_processes(void)
132 enable_nonboot_cpus();
133 pm_restore_console();
137 * pm_suspend_disk - The granpappy of hibernation power management.
139 * If we're going through the firmware, then get it over with quickly.
141 * If not, then call swsusp to do its thing, then figure out how
142 * to power down the system.
145 int pm_suspend_disk(void)
149 error
= prepare_processes();
153 if (pm_disk_mode
== PM_DISK_TESTPROC
)
157 error
= device_suspend(PMSG_FREEZE
);
160 printk("Some devices failed to suspend\n");
164 if (pm_disk_mode
== PM_DISK_TEST
) {
165 printk("swsusp debug: Waiting for 5 seconds.\n");
170 pr_debug("PM: snapshotting memory.\n");
172 if ((error
= swsusp_suspend()))
178 pr_debug("PM: writing image.\n");
179 error
= swsusp_write();
181 power_down(pm_disk_mode
);
187 pr_debug("PM: Image restored successfully.\n");
195 unprepare_processes();
201 * software_resume - Resume from a saved image.
203 * Called as a late_initcall (so all devices are discovered and
204 * initialized), we call swsusp to see if we have a saved image or not.
205 * If so, we quiesce devices, the restore the saved image. We will
206 * return above (in pm_suspend_disk() ) if everything goes well.
207 * Otherwise, we fail gracefully and return to the normally
212 static int software_resume(void)
216 mutex_lock(&pm_mutex
);
217 if (!swsusp_resume_device
) {
218 if (!strlen(resume_file
)) {
219 mutex_unlock(&pm_mutex
);
222 swsusp_resume_device
= name_to_dev_t(resume_file
);
223 pr_debug("swsusp: Resume From Partition %s\n", resume_file
);
225 pr_debug("swsusp: Resume From Partition %d:%d\n",
226 MAJOR(swsusp_resume_device
), MINOR(swsusp_resume_device
));
231 * FIXME: If noresume is specified, we need to find the partition
232 * and reset it back to normal swap space.
234 mutex_unlock(&pm_mutex
);
238 pr_debug("PM: Checking swsusp image.\n");
240 if ((error
= swsusp_check()))
243 pr_debug("PM: Preparing processes for restore.\n");
245 if ((error
= prepare_processes())) {
250 pr_debug("PM: Reading swsusp image.\n");
252 if ((error
= swsusp_read())) {
257 pr_debug("PM: Preparing devices for restore.\n");
260 if ((error
= device_suspend(PMSG_PRETHAW
))) {
262 printk("Some devices failed to suspend\n");
269 pr_debug("PM: Restoring saved image.\n");
271 pr_debug("PM: Restore failed, recovering.n");
275 unprepare_processes();
277 /* For success case, the suspend path will release the lock */
278 mutex_unlock(&pm_mutex
);
279 pr_debug("PM: Resume from disk failed.\n");
283 late_initcall(software_resume
);
286 static const char * const pm_disk_modes
[] = {
287 [PM_DISK_FIRMWARE
] = "firmware",
288 [PM_DISK_PLATFORM
] = "platform",
289 [PM_DISK_SHUTDOWN
] = "shutdown",
290 [PM_DISK_REBOOT
] = "reboot",
291 [PM_DISK_TEST
] = "test",
292 [PM_DISK_TESTPROC
] = "testproc",
296 * disk - Control suspend-to-disk mode
298 * Suspend-to-disk can be handled in several ways. The greatest
299 * distinction is who writes memory to disk - the firmware or the OS.
300 * If the firmware does it, we assume that it also handles suspending
302 * If the OS does it, then we have three options for putting the system
303 * to sleep - using the platform driver (e.g. ACPI or other PM registers),
304 * powering off the system or rebooting the system (for testing).
306 * The system will support either 'firmware' or 'platform', and that is
307 * known a priori (and encoded in pm_ops). But, the user may choose
308 * 'shutdown' or 'reboot' as alternatives.
310 * show() will display what the mode is currently set to.
311 * store() will accept one of
318 * It will only change to 'firmware' or 'platform' if the system
319 * supports it (as determined from pm_ops->pm_disk_mode).
322 static ssize_t
disk_show(struct subsystem
* subsys
, char * buf
)
324 return sprintf(buf
, "%s\n", pm_disk_modes
[pm_disk_mode
]);
328 static ssize_t
disk_store(struct subsystem
* s
, const char * buf
, size_t n
)
334 suspend_disk_method_t mode
= 0;
336 p
= memchr(buf
, '\n', n
);
337 len
= p
? p
- buf
: n
;
339 mutex_lock(&pm_mutex
);
340 for (i
= PM_DISK_FIRMWARE
; i
< PM_DISK_MAX
; i
++) {
341 if (!strncmp(buf
, pm_disk_modes
[i
], len
)) {
347 if (mode
== PM_DISK_SHUTDOWN
|| mode
== PM_DISK_REBOOT
||
348 mode
== PM_DISK_TEST
|| mode
== PM_DISK_TESTPROC
) {
351 if (pm_ops
&& pm_ops
->enter
&&
352 (mode
== pm_ops
->pm_disk_mode
))
361 pr_debug("PM: suspend-to-disk mode set to '%s'\n",
362 pm_disk_modes
[mode
]);
363 mutex_unlock(&pm_mutex
);
364 return error
? error
: n
;
369 static ssize_t
resume_show(struct subsystem
* subsys
, char *buf
)
371 return sprintf(buf
,"%d:%d\n", MAJOR(swsusp_resume_device
),
372 MINOR(swsusp_resume_device
));
375 static ssize_t
resume_store(struct subsystem
*subsys
, const char *buf
, size_t n
)
377 unsigned int maj
, min
;
381 if (sscanf(buf
, "%u:%u", &maj
, &min
) != 2)
384 res
= MKDEV(maj
,min
);
385 if (maj
!= MAJOR(res
) || min
!= MINOR(res
))
388 mutex_lock(&pm_mutex
);
389 swsusp_resume_device
= res
;
390 mutex_unlock(&pm_mutex
);
391 printk("Attempting manual resume\n");
401 static ssize_t
image_size_show(struct subsystem
* subsys
, char *buf
)
403 return sprintf(buf
, "%lu\n", image_size
);
406 static ssize_t
image_size_store(struct subsystem
* subsys
, const char * buf
, size_t n
)
410 if (sscanf(buf
, "%lu", &size
) == 1) {
418 power_attr(image_size
);
420 static struct attribute
* g
[] = {
423 &image_size_attr
.attr
,
428 static struct attribute_group attr_group
= {
433 static int __init
pm_disk_init(void)
435 return sysfs_create_group(&power_subsys
.kset
.kobj
,&attr_group
);
438 core_initcall(pm_disk_init
);
441 static int __init
resume_setup(char *str
)
446 strncpy( resume_file
, str
, 255 );
450 static int __init
resume_offset_setup(char *str
)
452 unsigned long long offset
;
457 if (sscanf(str
, "%llu", &offset
) == 1)
458 swsusp_resume_block
= offset
;
463 static int __init
noresume_setup(char *str
)
469 __setup("noresume", noresume_setup
);
470 __setup("resume_offset=", resume_offset_setup
);
471 __setup("resume=", resume_setup
);