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;
41 __HIBERNATION_AFTER_LAST
43 #define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
44 #define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
46 static int hibernation_mode = HIBERNATION_SHUTDOWN;
48 static struct hibernation_ops *hibernation_ops;
51 * hibernation_set_ops - set the global hibernate operations
52 * @ops: the hibernation operations to use in subsequent hibernation transitions
55 void hibernation_set_ops(struct hibernation_ops *ops)
57 if (ops && !(ops->prepare && ops->enter && ops->finish
58 && ops->pre_restore && ops->restore_cleanup)) {
62 mutex_lock(&pm_mutex);
63 hibernation_ops = ops;
65 hibernation_mode = HIBERNATION_PLATFORM;
66 else if (hibernation_mode == HIBERNATION_PLATFORM)
67 hibernation_mode = HIBERNATION_SHUTDOWN;
69 mutex_unlock(&pm_mutex);
74 * platform_prepare - prepare the machine for hibernation using the
75 * platform driver if so configured and return an error code if it fails
78 static int platform_prepare(int platform_mode)
80 return (platform_mode && hibernation_ops) ?
81 hibernation_ops->prepare() : 0;
85 * platform_finish - switch the machine to the normal mode of operation
86 * using the platform driver (must be called after platform_prepare())
89 static void platform_finish(int platform_mode)
91 if (platform_mode && hibernation_ops)
92 hibernation_ops->finish();
96 * platform_pre_restore - prepare the platform for the restoration from a
97 * hibernation image. If the restore fails after this function has been
98 * called, platform_restore_cleanup() must be called.
101 static int platform_pre_restore(int platform_mode)
103 return (platform_mode && hibernation_ops) ?
104 hibernation_ops->pre_restore() : 0;
108 * platform_restore_cleanup - switch the platform to the normal mode of
109 * operation after a failing restore. If platform_pre_restore() has been
110 * called before the failing restore, this function must be called too,
111 * regardless of the result of platform_pre_restore().
114 static void platform_restore_cleanup(int platform_mode)
116 if (platform_mode && hibernation_ops)
117 hibernation_ops->restore_cleanup();
121 * hibernation_snapshot - quiesce devices and create the hibernation
123 * @platform_mode - if set, use the platform driver, if available, to
124 * prepare the platform frimware for the power transition.
126 * Must be called with pm_mutex held
129 int hibernation_snapshot(int platform_mode)
133 /* Free memory before shutting down devices. */
134 error = swsusp_shrink_memory();
139 error = device_suspend(PMSG_FREEZE);
143 error = platform_prepare(platform_mode);
147 error = disable_nonboot_cpus();
149 if (hibernation_mode != HIBERNATION_TEST) {
151 error = swsusp_suspend();
152 /* Control returns here after successful restore */
154 printk("swsusp debug: Waiting for 5 seconds.\n");
158 enable_nonboot_cpus();
160 platform_finish(platform_mode);
168 * hibernation_restore - quiesce devices and restore the hibernation
169 * snapshot image. If successful, control returns in hibernation_snaphot()
170 * @platform_mode - if set, use the platform driver, if available, to
171 * prepare the platform frimware for the transition.
173 * Must be called with pm_mutex held
176 int hibernation_restore(int platform_mode)
180 pm_prepare_console();
182 error = device_suspend(PMSG_PRETHAW);
186 error = platform_pre_restore(platform_mode);
188 error = disable_nonboot_cpus();
190 error = swsusp_resume();
191 enable_nonboot_cpus();
193 platform_restore_cleanup(platform_mode);
197 pm_restore_console();
202 * hibernation_platform_enter - enter the hibernation state using the
203 * platform driver (if available)
206 int hibernation_platform_enter(void)
210 if (hibernation_ops) {
211 kernel_shutdown_prepare(SYSTEM_SUSPEND_DISK);
213 * We have cancelled the power transition by running
214 * hibernation_ops->finish() before saving the image, so we
215 * should let the firmware know that we're going to enter the
216 * sleep state after all
218 error = hibernation_ops->prepare();
220 error = hibernation_ops->enter();
228 * power_down - Shut the machine down for hibernation.
230 * Use the platform driver, if configured so; otherwise try
231 * to power off or reboot.
234 static void power_down(void)
236 switch (hibernation_mode) {
237 case HIBERNATION_TEST:
238 case HIBERNATION_TESTPROC:
240 case HIBERNATION_SHUTDOWN:
243 case HIBERNATION_REBOOT:
244 kernel_restart(NULL);
246 case HIBERNATION_PLATFORM:
247 hibernation_platform_enter();
251 * Valid image is on the disk, if we continue we risk serious data
252 * corruption after resume.
254 printk(KERN_CRIT "Please power me down manually\n");
258 static void unprepare_processes(void)
261 pm_restore_console();
264 static int prepare_processes(void)
268 pm_prepare_console();
269 if (freeze_processes()) {
271 unprepare_processes();
277 * hibernate - The granpappy of the built-in hibernation management
284 /* The snapshot device should not be opened while we're running */
285 if (!atomic_add_unless(&snapshot_device_available, -1, 0))
288 /* Allocate memory management structures */
289 error = create_basic_memory_bitmaps();
293 error = prepare_processes();
297 mutex_lock(&pm_mutex);
298 if (hibernation_mode == HIBERNATION_TESTPROC) {
299 printk("swsusp debug: Waiting for 5 seconds.\n");
303 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
304 if (in_suspend && !error) {
305 unsigned int flags = 0;
307 if (hibernation_mode == HIBERNATION_PLATFORM)
308 flags |= SF_PLATFORM_MODE;
309 pr_debug("PM: writing image.\n");
310 error = swsusp_write(flags);
315 pr_debug("PM: Image restored successfully.\n");
319 mutex_unlock(&pm_mutex);
320 unprepare_processes();
322 free_basic_memory_bitmaps();
324 atomic_inc(&snapshot_device_available);
330 * software_resume - Resume from a saved image.
332 * Called as a late_initcall (so all devices are discovered and
333 * initialized), we call swsusp to see if we have a saved image or not.
334 * If so, we quiesce devices, the restore the saved image. We will
335 * return above (in hibernate() ) if everything goes well.
336 * Otherwise, we fail gracefully and return to the normally
341 static int software_resume(void)
346 mutex_lock(&pm_mutex);
347 if (!swsusp_resume_device) {
348 if (!strlen(resume_file)) {
349 mutex_unlock(&pm_mutex);
352 swsusp_resume_device = name_to_dev_t(resume_file);
353 pr_debug("swsusp: Resume From Partition %s\n", resume_file);
355 pr_debug("swsusp: Resume From Partition %d:%d\n",
356 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
361 * FIXME: If noresume is specified, we need to find the partition
362 * and reset it back to normal swap space.
364 mutex_unlock(&pm_mutex);
368 pr_debug("PM: Checking swsusp image.\n");
369 error = swsusp_check();
373 /* The snapshot device should not be opened while we're running */
374 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
379 error = create_basic_memory_bitmaps();
383 pr_debug("PM: Preparing processes for restore.\n");
384 error = prepare_processes();
390 pr_debug("PM: Reading swsusp image.\n");
392 error = swsusp_read(&flags);
394 hibernation_restore(flags & SF_PLATFORM_MODE);
396 printk(KERN_ERR "PM: Restore failed, recovering.\n");
398 unprepare_processes();
400 free_basic_memory_bitmaps();
402 atomic_inc(&snapshot_device_available);
403 /* For success case, the suspend path will release the lock */
405 mutex_unlock(&pm_mutex);
406 pr_debug("PM: Resume from disk failed.\n");
410 late_initcall(software_resume);
413 static const char * const hibernation_modes[] = {
414 [HIBERNATION_PLATFORM] = "platform",
415 [HIBERNATION_SHUTDOWN] = "shutdown",
416 [HIBERNATION_REBOOT] = "reboot",
417 [HIBERNATION_TEST] = "test",
418 [HIBERNATION_TESTPROC] = "testproc",
422 * disk - Control hibernation mode
424 * Suspend-to-disk can be handled in several ways. We have a few options
425 * for putting the system to sleep - using the platform driver (e.g. ACPI
426 * or other hibernation_ops), powering off the system or rebooting the
427 * system (for testing) as well as the two test modes.
429 * The system can support 'platform', and that is known a priori (and
430 * encoded by the presence of hibernation_ops). However, the user may
431 * choose 'shutdown' or 'reboot' as alternatives, as well as one fo the
432 * test modes, 'test' or 'testproc'.
434 * show() will display what the mode is currently set to.
435 * store() will accept one of
443 * It will only change to 'platform' if the system
444 * supports it (as determined by having hibernation_ops).
447 static ssize_t disk_show(struct kset *kset, char *buf)
452 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
453 if (!hibernation_modes[i])
456 case HIBERNATION_SHUTDOWN:
457 case HIBERNATION_REBOOT:
458 case HIBERNATION_TEST:
459 case HIBERNATION_TESTPROC:
461 case HIBERNATION_PLATFORM:
464 /* not a valid mode, continue with loop */
467 if (i == hibernation_mode)
468 buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
470 buf += sprintf(buf, "%s ", hibernation_modes[i]);
472 buf += sprintf(buf, "\n");
477 static ssize_t disk_store(struct kset *kset, const char *buf, size_t n)
483 int mode = HIBERNATION_INVALID;
485 p = memchr(buf, '\n', n);
486 len = p ? p - buf : n;
488 mutex_lock(&pm_mutex);
489 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
490 if (len == strlen(hibernation_modes[i])
491 && !strncmp(buf, hibernation_modes[i], len)) {
496 if (mode != HIBERNATION_INVALID) {
498 case HIBERNATION_SHUTDOWN:
499 case HIBERNATION_REBOOT:
500 case HIBERNATION_TEST:
501 case HIBERNATION_TESTPROC:
502 hibernation_mode = mode;
504 case HIBERNATION_PLATFORM:
506 hibernation_mode = mode;
514 pr_debug("PM: suspend-to-disk mode set to '%s'\n",
515 hibernation_modes[mode]);
516 mutex_unlock(&pm_mutex);
517 return error ? error : n;
522 static ssize_t resume_show(struct kset *kset, char *buf)
524 return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
525 MINOR(swsusp_resume_device));
528 static ssize_t resume_store(struct kset *kset, const char *buf, size_t n)
530 unsigned int maj, min;
534 if (sscanf(buf, "%u:%u", &maj, &min) != 2)
537 res = MKDEV(maj,min);
538 if (maj != MAJOR(res) || min != MINOR(res))
541 mutex_lock(&pm_mutex);
542 swsusp_resume_device = res;
543 mutex_unlock(&pm_mutex);
544 printk("Attempting manual resume\n");
554 static ssize_t image_size_show(struct kset *kset, char *buf)
556 return sprintf(buf, "%lu\n", image_size);
559 static ssize_t image_size_store(struct kset *kset, const char *buf, size_t n)
563 if (sscanf(buf, "%lu", &size) == 1) {
571 power_attr(image_size);
573 static struct attribute * g[] = {
576 &image_size_attr.attr,
581 static struct attribute_group attr_group = {
586 static int __init pm_disk_init(void)
588 return sysfs_create_group(&power_subsys.kobj, &attr_group);
591 core_initcall(pm_disk_init);
594 static int __init resume_setup(char *str)
599 strncpy( resume_file, str, 255 );
603 static int __init resume_offset_setup(char *str)
605 unsigned long long offset;
610 if (sscanf(str, "%llu", &offset) == 1)
611 swsusp_resume_block = offset;
616 static int __init noresume_setup(char *str)
622 __setup("noresume", noresume_setup);
623 __setup("resume_offset=", resume_offset_setup);
624 __setup("resume=", resume_setup);