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 switch (pm_disk_mode) {
44 case PM_DISK_TESTPROC:
45 case PM_DISK_SHUTDOWN:
49 if (pm_ops && pm_ops->prepare)
50 error = pm_ops->prepare(PM_SUSPEND_DISK);
56 * power_down - Shut machine down for hibernate.
58 * Use the platform driver, if configured so; otherwise try
59 * to power off or reboot.
62 static void power_down(void)
64 switch (pm_disk_mode) {
66 case PM_DISK_TESTPROC:
68 case PM_DISK_SHUTDOWN:
75 if (pm_ops && pm_ops->enter) {
76 kernel_shutdown_prepare(SYSTEM_SUSPEND_DISK);
77 pm_ops->enter(PM_SUSPEND_DISK);
83 * Valid image is on the disk, if we continue we risk serious data
84 * corruption after resume.
86 printk(KERN_CRIT "Please power me down manually\n");
90 static inline void platform_finish(void)
92 switch (pm_disk_mode) {
94 case PM_DISK_TESTPROC:
95 case PM_DISK_SHUTDOWN:
99 if (pm_ops && pm_ops->finish)
100 pm_ops->finish(PM_SUSPEND_DISK);
104 static void unprepare_processes(void)
107 pm_restore_console();
110 static int prepare_processes(void)
114 pm_prepare_console();
115 if (freeze_processes()) {
117 unprepare_processes();
123 * pm_suspend_disk - The granpappy of hibernation power management.
125 * If not, then call swsusp to do its thing, then figure out how
126 * to power down the system.
129 int pm_suspend_disk(void)
133 /* The snapshot device should not be opened while we're running */
134 if (!atomic_add_unless(&snapshot_device_available, -1, 0))
137 /* Allocate memory management structures */
138 error = create_basic_memory_bitmaps();
142 error = prepare_processes();
146 if (pm_disk_mode == PM_DISK_TESTPROC) {
147 printk("swsusp debug: Waiting for 5 seconds.\n");
152 /* Free memory before shutting down devices. */
153 error = swsusp_shrink_memory();
157 error = platform_prepare();
162 error = device_suspend(PMSG_FREEZE);
164 printk(KERN_ERR "PM: Some devices failed to suspend\n");
167 error = disable_nonboot_cpus();
171 if (pm_disk_mode == PM_DISK_TEST) {
172 printk("swsusp debug: Waiting for 5 seconds.\n");
177 pr_debug("PM: snapshotting memory.\n");
179 error = swsusp_suspend();
184 enable_nonboot_cpus();
188 pr_debug("PM: writing image.\n");
189 error = swsusp_write();
197 pr_debug("PM: Image restored successfully.\n");
202 enable_nonboot_cpus();
208 unprepare_processes();
210 free_basic_memory_bitmaps();
212 atomic_inc(&snapshot_device_available);
218 * software_resume - Resume from a saved image.
220 * Called as a late_initcall (so all devices are discovered and
221 * initialized), we call swsusp to see if we have a saved image or not.
222 * If so, we quiesce devices, the restore the saved image. We will
223 * return above (in pm_suspend_disk() ) if everything goes well.
224 * Otherwise, we fail gracefully and return to the normally
229 static int software_resume(void)
233 mutex_lock(&pm_mutex);
234 if (!swsusp_resume_device) {
235 if (!strlen(resume_file)) {
236 mutex_unlock(&pm_mutex);
239 swsusp_resume_device = name_to_dev_t(resume_file);
240 pr_debug("swsusp: Resume From Partition %s\n", resume_file);
242 pr_debug("swsusp: Resume From Partition %d:%d\n",
243 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
248 * FIXME: If noresume is specified, we need to find the partition
249 * and reset it back to normal swap space.
251 mutex_unlock(&pm_mutex);
255 pr_debug("PM: Checking swsusp image.\n");
256 error = swsusp_check();
260 /* The snapshot device should not be opened while we're running */
261 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
266 error = create_basic_memory_bitmaps();
270 pr_debug("PM: Preparing processes for restore.\n");
271 error = prepare_processes();
277 pr_debug("PM: Reading swsusp image.\n");
279 error = swsusp_read();
285 pr_debug("PM: Preparing devices for restore.\n");
288 error = device_suspend(PMSG_PRETHAW);
292 error = disable_nonboot_cpus();
296 enable_nonboot_cpus();
302 printk(KERN_ERR "PM: Restore failed, recovering.\n");
303 unprepare_processes();
305 free_basic_memory_bitmaps();
307 atomic_inc(&snapshot_device_available);
308 /* For success case, the suspend path will release the lock */
310 mutex_unlock(&pm_mutex);
311 pr_debug("PM: Resume from disk failed.\n");
315 late_initcall(software_resume);
318 static const char * const pm_disk_modes[] = {
319 [PM_DISK_PLATFORM] = "platform",
320 [PM_DISK_SHUTDOWN] = "shutdown",
321 [PM_DISK_REBOOT] = "reboot",
322 [PM_DISK_TEST] = "test",
323 [PM_DISK_TESTPROC] = "testproc",
327 * disk - Control suspend-to-disk mode
329 * Suspend-to-disk can be handled in several ways. We have a few options
330 * for putting the system to sleep - using the platform driver (e.g. ACPI
331 * or other pm_ops), powering off the system or rebooting the system
332 * (for testing) as well as the two test modes.
334 * The system can support 'platform', and that is known a priori (and
335 * encoded in pm_ops). However, the user may choose 'shutdown' or 'reboot'
336 * as alternatives, as well as the test modes 'test' and 'testproc'.
338 * show() will display what the mode is currently set to.
339 * store() will accept one of
347 * It will only change to 'platform' if the system
348 * supports it (as determined from pm_ops->pm_disk_mode).
351 static ssize_t disk_show(struct kset *kset, char *buf)
356 for (i = PM_DISK_PLATFORM; i < PM_DISK_MAX; i++) {
357 if (!pm_disk_modes[i])
360 case PM_DISK_SHUTDOWN:
363 case PM_DISK_TESTPROC:
366 if (pm_ops && pm_ops->enter &&
367 (i == pm_ops->pm_disk_mode))
369 /* not a valid mode, continue with loop */
372 if (i == pm_disk_mode)
373 buf += sprintf(buf, "[%s]", pm_disk_modes[i]);
375 buf += sprintf(buf, "%s", pm_disk_modes[i]);
376 if (i+1 != PM_DISK_MAX)
377 buf += sprintf(buf, " ");
379 buf += sprintf(buf, "\n");
384 static ssize_t disk_store(struct kset *kset, const char *buf, size_t n)
390 suspend_disk_method_t mode = 0;
392 p = memchr(buf, '\n', n);
393 len = p ? p - buf : n;
395 mutex_lock(&pm_mutex);
396 for (i = PM_DISK_PLATFORM; i < PM_DISK_MAX; i++) {
397 if (!strncmp(buf, pm_disk_modes[i], len)) {
404 case PM_DISK_SHUTDOWN:
407 case PM_DISK_TESTPROC:
411 if (pm_ops && pm_ops->enter &&
412 (mode == pm_ops->pm_disk_mode))
421 pr_debug("PM: suspend-to-disk mode set to '%s'\n",
422 pm_disk_modes[mode]);
423 mutex_unlock(&pm_mutex);
424 return error ? error : n;
429 static ssize_t resume_show(struct kset *kset, char *buf)
431 return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
432 MINOR(swsusp_resume_device));
435 static ssize_t resume_store(struct kset *kset, const char *buf, size_t n)
437 unsigned int maj, min;
441 if (sscanf(buf, "%u:%u", &maj, &min) != 2)
444 res = MKDEV(maj,min);
445 if (maj != MAJOR(res) || min != MINOR(res))
448 mutex_lock(&pm_mutex);
449 swsusp_resume_device = res;
450 mutex_unlock(&pm_mutex);
451 printk("Attempting manual resume\n");
461 static ssize_t image_size_show(struct kset *kset, char *buf)
463 return sprintf(buf, "%lu\n", image_size);
466 static ssize_t image_size_store(struct kset *kset, const char *buf, size_t n)
470 if (sscanf(buf, "%lu", &size) == 1) {
478 power_attr(image_size);
480 static struct attribute * g[] = {
483 &image_size_attr.attr,
488 static struct attribute_group attr_group = {
493 static int __init pm_disk_init(void)
495 return sysfs_create_group(&power_subsys.kobj, &attr_group);
498 core_initcall(pm_disk_init);
501 static int __init resume_setup(char *str)
506 strncpy( resume_file, str, 255 );
510 static int __init resume_offset_setup(char *str)
512 unsigned long long offset;
517 if (sscanf(str, "%llu", &offset) == 1)
518 swsusp_resume_block = offset;
523 static int __init noresume_setup(char *str)
529 __setup("noresume", noresume_setup);
530 __setup("resume_offset=", resume_offset_setup);
531 __setup("resume=", resume_setup);