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)
208 if (hibernation_ops) {
209 kernel_shutdown_prepare(SYSTEM_SUSPEND_DISK);
210 return hibernation_ops->enter();
217 * power_down - Shut the machine down for hibernation.
219 * Use the platform driver, if configured so; otherwise try
220 * to power off or reboot.
223 static void power_down(void)
225 switch (hibernation_mode) {
226 case HIBERNATION_TEST:
227 case HIBERNATION_TESTPROC:
229 case HIBERNATION_SHUTDOWN:
232 case HIBERNATION_REBOOT:
233 kernel_restart(NULL);
235 case HIBERNATION_PLATFORM:
236 hibernation_platform_enter();
240 * Valid image is on the disk, if we continue we risk serious data
241 * corruption after resume.
243 printk(KERN_CRIT "Please power me down manually\n");
247 static void unprepare_processes(void)
250 pm_restore_console();
253 static int prepare_processes(void)
257 pm_prepare_console();
258 if (freeze_processes()) {
260 unprepare_processes();
266 * hibernate - The granpappy of the built-in hibernation management
273 /* The snapshot device should not be opened while we're running */
274 if (!atomic_add_unless(&snapshot_device_available, -1, 0))
277 /* Allocate memory management structures */
278 error = create_basic_memory_bitmaps();
282 error = prepare_processes();
286 mutex_lock(&pm_mutex);
287 if (hibernation_mode == HIBERNATION_TESTPROC) {
288 printk("swsusp debug: Waiting for 5 seconds.\n");
292 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
293 if (in_suspend && !error) {
294 unsigned int flags = 0;
296 if (hibernation_mode == HIBERNATION_PLATFORM)
297 flags |= SF_PLATFORM_MODE;
298 pr_debug("PM: writing image.\n");
299 error = swsusp_write(flags);
304 pr_debug("PM: Image restored successfully.\n");
308 mutex_unlock(&pm_mutex);
309 unprepare_processes();
311 free_basic_memory_bitmaps();
313 atomic_inc(&snapshot_device_available);
319 * software_resume - Resume from a saved image.
321 * Called as a late_initcall (so all devices are discovered and
322 * initialized), we call swsusp to see if we have a saved image or not.
323 * If so, we quiesce devices, the restore the saved image. We will
324 * return above (in hibernate() ) if everything goes well.
325 * Otherwise, we fail gracefully and return to the normally
330 static int software_resume(void)
335 mutex_lock(&pm_mutex);
336 if (!swsusp_resume_device) {
337 if (!strlen(resume_file)) {
338 mutex_unlock(&pm_mutex);
341 swsusp_resume_device = name_to_dev_t(resume_file);
342 pr_debug("swsusp: Resume From Partition %s\n", resume_file);
344 pr_debug("swsusp: Resume From Partition %d:%d\n",
345 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
350 * FIXME: If noresume is specified, we need to find the partition
351 * and reset it back to normal swap space.
353 mutex_unlock(&pm_mutex);
357 pr_debug("PM: Checking swsusp image.\n");
358 error = swsusp_check();
362 /* The snapshot device should not be opened while we're running */
363 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
368 error = create_basic_memory_bitmaps();
372 pr_debug("PM: Preparing processes for restore.\n");
373 error = prepare_processes();
379 pr_debug("PM: Reading swsusp image.\n");
381 error = swsusp_read(&flags);
383 hibernation_restore(flags & SF_PLATFORM_MODE);
385 printk(KERN_ERR "PM: Restore failed, recovering.\n");
387 unprepare_processes();
389 free_basic_memory_bitmaps();
391 atomic_inc(&snapshot_device_available);
392 /* For success case, the suspend path will release the lock */
394 mutex_unlock(&pm_mutex);
395 pr_debug("PM: Resume from disk failed.\n");
399 late_initcall(software_resume);
402 static const char * const hibernation_modes[] = {
403 [HIBERNATION_PLATFORM] = "platform",
404 [HIBERNATION_SHUTDOWN] = "shutdown",
405 [HIBERNATION_REBOOT] = "reboot",
406 [HIBERNATION_TEST] = "test",
407 [HIBERNATION_TESTPROC] = "testproc",
411 * disk - Control hibernation mode
413 * Suspend-to-disk can be handled in several ways. We have a few options
414 * for putting the system to sleep - using the platform driver (e.g. ACPI
415 * or other hibernation_ops), powering off the system or rebooting the
416 * system (for testing) as well as the two test modes.
418 * The system can support 'platform', and that is known a priori (and
419 * encoded by the presence of hibernation_ops). However, the user may
420 * choose 'shutdown' or 'reboot' as alternatives, as well as one fo the
421 * test modes, 'test' or 'testproc'.
423 * show() will display what the mode is currently set to.
424 * store() will accept one of
432 * It will only change to 'platform' if the system
433 * supports it (as determined by having hibernation_ops).
436 static ssize_t disk_show(struct kset *kset, char *buf)
441 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
442 if (!hibernation_modes[i])
445 case HIBERNATION_SHUTDOWN:
446 case HIBERNATION_REBOOT:
447 case HIBERNATION_TEST:
448 case HIBERNATION_TESTPROC:
450 case HIBERNATION_PLATFORM:
453 /* not a valid mode, continue with loop */
456 if (i == hibernation_mode)
457 buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
459 buf += sprintf(buf, "%s ", hibernation_modes[i]);
461 buf += sprintf(buf, "\n");
466 static ssize_t disk_store(struct kset *kset, const char *buf, size_t n)
472 int mode = HIBERNATION_INVALID;
474 p = memchr(buf, '\n', n);
475 len = p ? p - buf : n;
477 mutex_lock(&pm_mutex);
478 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
479 if (len == strlen(hibernation_modes[i])
480 && !strncmp(buf, hibernation_modes[i], len)) {
485 if (mode != HIBERNATION_INVALID) {
487 case HIBERNATION_SHUTDOWN:
488 case HIBERNATION_REBOOT:
489 case HIBERNATION_TEST:
490 case HIBERNATION_TESTPROC:
491 hibernation_mode = mode;
493 case HIBERNATION_PLATFORM:
495 hibernation_mode = mode;
503 pr_debug("PM: suspend-to-disk mode set to '%s'\n",
504 hibernation_modes[mode]);
505 mutex_unlock(&pm_mutex);
506 return error ? error : n;
511 static ssize_t resume_show(struct kset *kset, char *buf)
513 return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
514 MINOR(swsusp_resume_device));
517 static ssize_t resume_store(struct kset *kset, const char *buf, size_t n)
519 unsigned int maj, min;
523 if (sscanf(buf, "%u:%u", &maj, &min) != 2)
526 res = MKDEV(maj,min);
527 if (maj != MAJOR(res) || min != MINOR(res))
530 mutex_lock(&pm_mutex);
531 swsusp_resume_device = res;
532 mutex_unlock(&pm_mutex);
533 printk("Attempting manual resume\n");
543 static ssize_t image_size_show(struct kset *kset, char *buf)
545 return sprintf(buf, "%lu\n", image_size);
548 static ssize_t image_size_store(struct kset *kset, const char *buf, size_t n)
552 if (sscanf(buf, "%lu", &size) == 1) {
560 power_attr(image_size);
562 static struct attribute * g[] = {
565 &image_size_attr.attr,
570 static struct attribute_group attr_group = {
575 static int __init pm_disk_init(void)
577 return sysfs_create_group(&power_subsys.kobj, &attr_group);
580 core_initcall(pm_disk_init);
583 static int __init resume_setup(char *str)
588 strncpy( resume_file, str, 255 );
592 static int __init resume_offset_setup(char *str)
594 unsigned long long offset;
599 if (sscanf(str, "%llu", &offset) == 1)
600 swsusp_resume_block = offset;
605 static int __init noresume_setup(char *str)
611 __setup("noresume", noresume_setup);
612 __setup("resume_offset=", resume_offset_setup);
613 __setup("resume=", resume_setup);