PM/Hibernate: Rename disk.c to hibernate.c
Change the name of kernel/power/disk.c to kernel/power/hibernate.c
in analogy with the file names introduced by the changes that
separated the suspend to RAM and standby funtionality from the
common PM functions.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
new file mode 100644
index 0000000..81d2e74
--- /dev/null
+++ b/kernel/power/hibernate.c
@@ -0,0 +1,955 @@
+/*
+ * kernel/power/hibernate.c - Hibernation (a.k.a suspend-to-disk) support.
+ *
+ * Copyright (c) 2003 Patrick Mochel
+ * Copyright (c) 2003 Open Source Development Lab
+ * Copyright (c) 2004 Pavel Machek <pavel@suse.cz>
+ * Copyright (c) 2009 Rafael J. Wysocki, Novell Inc.
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/suspend.h>
+#include <linux/syscalls.h>
+#include <linux/reboot.h>
+#include <linux/string.h>
+#include <linux/device.h>
+#include <linux/kmod.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/pm.h>
+#include <linux/console.h>
+#include <linux/cpu.h>
+#include <linux/freezer.h>
+#include <scsi/scsi_scan.h>
+#include <asm/suspend.h>
+
+#include "power.h"
+
+
+static int noresume = 0;
+static char resume_file[256] = CONFIG_PM_STD_PARTITION;
+dev_t swsusp_resume_device;
+sector_t swsusp_resume_block;
+
+enum {
+ HIBERNATION_INVALID,
+ HIBERNATION_PLATFORM,
+ HIBERNATION_TEST,
+ HIBERNATION_TESTPROC,
+ HIBERNATION_SHUTDOWN,
+ HIBERNATION_REBOOT,
+ /* keep last */
+ __HIBERNATION_AFTER_LAST
+};
+#define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
+#define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
+
+static int hibernation_mode = HIBERNATION_SHUTDOWN;
+
+static struct platform_hibernation_ops *hibernation_ops;
+
+/**
+ * hibernation_set_ops - set the global hibernate operations
+ * @ops: the hibernation operations to use in subsequent hibernation transitions
+ */
+
+void hibernation_set_ops(struct platform_hibernation_ops *ops)
+{
+ if (ops && !(ops->begin && ops->end && ops->pre_snapshot
+ && ops->prepare && ops->finish && ops->enter && ops->pre_restore
+ && ops->restore_cleanup)) {
+ WARN_ON(1);
+ return;
+ }
+ mutex_lock(&pm_mutex);
+ hibernation_ops = ops;
+ if (ops)
+ hibernation_mode = HIBERNATION_PLATFORM;
+ else if (hibernation_mode == HIBERNATION_PLATFORM)
+ hibernation_mode = HIBERNATION_SHUTDOWN;
+
+ mutex_unlock(&pm_mutex);
+}
+
+static bool entering_platform_hibernation;
+
+bool system_entering_hibernation(void)
+{
+ return entering_platform_hibernation;
+}
+EXPORT_SYMBOL(system_entering_hibernation);
+
+#ifdef CONFIG_PM_DEBUG
+static void hibernation_debug_sleep(void)
+{
+ printk(KERN_INFO "hibernation debug: Waiting for 5 seconds.\n");
+ mdelay(5000);
+}
+
+static int hibernation_testmode(int mode)
+{
+ if (hibernation_mode == mode) {
+ hibernation_debug_sleep();
+ return 1;
+ }
+ return 0;
+}
+
+static int hibernation_test(int level)
+{
+ if (pm_test_level == level) {
+ hibernation_debug_sleep();
+ return 1;
+ }
+ return 0;
+}
+#else /* !CONFIG_PM_DEBUG */
+static int hibernation_testmode(int mode) { return 0; }
+static int hibernation_test(int level) { return 0; }
+#endif /* !CONFIG_PM_DEBUG */
+
+/**
+ * platform_begin - tell the platform driver that we're starting
+ * hibernation
+ */
+
+static int platform_begin(int platform_mode)
+{
+ return (platform_mode && hibernation_ops) ?
+ hibernation_ops->begin() : 0;
+}
+
+/**
+ * platform_end - tell the platform driver that we've entered the
+ * working state
+ */
+
+static void platform_end(int platform_mode)
+{
+ if (platform_mode && hibernation_ops)
+ hibernation_ops->end();
+}
+
+/**
+ * platform_pre_snapshot - prepare the machine for hibernation using the
+ * platform driver if so configured and return an error code if it fails
+ */
+
+static int platform_pre_snapshot(int platform_mode)
+{
+ return (platform_mode && hibernation_ops) ?
+ hibernation_ops->pre_snapshot() : 0;
+}
+
+/**
+ * platform_leave - prepare the machine for switching to the normal mode
+ * of operation using the platform driver (called with interrupts disabled)
+ */
+
+static void platform_leave(int platform_mode)
+{
+ if (platform_mode && hibernation_ops)
+ hibernation_ops->leave();
+}
+
+/**
+ * platform_finish - switch the machine to the normal mode of operation
+ * using the platform driver (must be called after platform_prepare())
+ */
+
+static void platform_finish(int platform_mode)
+{
+ if (platform_mode && hibernation_ops)
+ hibernation_ops->finish();
+}
+
+/**
+ * platform_pre_restore - prepare the platform for the restoration from a
+ * hibernation image. If the restore fails after this function has been
+ * called, platform_restore_cleanup() must be called.
+ */
+
+static int platform_pre_restore(int platform_mode)
+{
+ return (platform_mode && hibernation_ops) ?
+ hibernation_ops->pre_restore() : 0;
+}
+
+/**
+ * platform_restore_cleanup - switch the platform to the normal mode of
+ * operation after a failing restore. If platform_pre_restore() has been
+ * called before the failing restore, this function must be called too,
+ * regardless of the result of platform_pre_restore().
+ */
+
+static void platform_restore_cleanup(int platform_mode)
+{
+ if (platform_mode && hibernation_ops)
+ hibernation_ops->restore_cleanup();
+}
+
+/**
+ * platform_recover - recover the platform from a failure to suspend
+ * devices.
+ */
+
+static void platform_recover(int platform_mode)
+{
+ if (platform_mode && hibernation_ops && hibernation_ops->recover)
+ hibernation_ops->recover();
+}
+
+/**
+ * create_image - freeze devices that need to be frozen with interrupts
+ * off, create the hibernation image and thaw those devices. Control
+ * reappears in this routine after a restore.
+ */
+
+static int create_image(int platform_mode)
+{
+ int error;
+
+ error = arch_prepare_suspend();
+ if (error)
+ return error;
+
+ /* At this point, dpm_suspend_start() has been called, but *not*
+ * dpm_suspend_noirq(). We *must* call dpm_suspend_noirq() now.
+ * Otherwise, drivers for some devices (e.g. interrupt controllers)
+ * become desynchronized with the actual state of the hardware
+ * at resume time, and evil weirdness ensues.
+ */
+ error = dpm_suspend_noirq(PMSG_FREEZE);
+ if (error) {
+ printk(KERN_ERR "PM: Some devices failed to power down, "
+ "aborting hibernation\n");
+ return error;
+ }
+
+ error = platform_pre_snapshot(platform_mode);
+ if (error || hibernation_test(TEST_PLATFORM))
+ goto Platform_finish;
+
+ error = disable_nonboot_cpus();
+ if (error || hibernation_test(TEST_CPUS)
+ || hibernation_testmode(HIBERNATION_TEST))
+ goto Enable_cpus;
+
+ local_irq_disable();
+
+ error = sysdev_suspend(PMSG_FREEZE);
+ if (error) {
+ printk(KERN_ERR "PM: Some system devices failed to power down, "
+ "aborting hibernation\n");
+ goto Enable_irqs;
+ }
+
+ if (hibernation_test(TEST_CORE))
+ goto Power_up;
+
+ in_suspend = 1;
+ save_processor_state();
+ error = swsusp_arch_suspend();
+ if (error)
+ printk(KERN_ERR "PM: Error %d creating hibernation image\n",
+ error);
+ /* Restore control flow magically appears here */
+ restore_processor_state();
+ if (!in_suspend)
+ platform_leave(platform_mode);
+
+ Power_up:
+ sysdev_resume();
+ /* NOTE: dpm_resume_noirq() is just a resume() for devices
+ * that suspended with irqs off ... no overall powerup.
+ */
+
+ Enable_irqs:
+ local_irq_enable();
+
+ Enable_cpus:
+ enable_nonboot_cpus();
+
+ Platform_finish:
+ platform_finish(platform_mode);
+
+ dpm_resume_noirq(in_suspend ?
+ (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
+
+ return error;
+}
+
+/**
+ * hibernation_snapshot - quiesce devices and create the hibernation
+ * snapshot image.
+ * @platform_mode - if set, use the platform driver, if available, to
+ * prepare the platform firmware for the power transition.
+ *
+ * Must be called with pm_mutex held
+ */
+
+int hibernation_snapshot(int platform_mode)
+{
+ int error;
+
+ error = platform_begin(platform_mode);
+ if (error)
+ return error;
+
+ /* Free memory before shutting down devices. */
+ error = swsusp_shrink_memory();
+ if (error)
+ goto Close;
+
+ suspend_console();
+ error = dpm_suspend_start(PMSG_FREEZE);
+ if (error)
+ goto Recover_platform;
+
+ if (hibernation_test(TEST_DEVICES))
+ goto Recover_platform;
+
+ error = create_image(platform_mode);
+ /* Control returns here after successful restore */
+
+ Resume_devices:
+ dpm_resume_end(in_suspend ?
+ (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
+ resume_console();
+ Close:
+ platform_end(platform_mode);
+ return error;
+
+ Recover_platform:
+ platform_recover(platform_mode);
+ goto Resume_devices;
+}
+
+/**
+ * resume_target_kernel - prepare devices that need to be suspended with
+ * interrupts off, restore the contents of highmem that have not been
+ * restored yet from the image and run the low level code that will restore
+ * the remaining contents of memory and switch to the just restored target
+ * kernel.
+ */
+
+static int resume_target_kernel(bool platform_mode)
+{
+ int error;
+
+ error = dpm_suspend_noirq(PMSG_QUIESCE);
+ if (error) {
+ printk(KERN_ERR "PM: Some devices failed to power down, "
+ "aborting resume\n");
+ return error;
+ }
+
+ error = platform_pre_restore(platform_mode);
+ if (error)
+ goto Cleanup;
+
+ error = disable_nonboot_cpus();
+ if (error)
+ goto Enable_cpus;
+
+ local_irq_disable();
+
+ error = sysdev_suspend(PMSG_QUIESCE);
+ if (error)
+ goto Enable_irqs;
+
+ /* We'll ignore saved state, but this gets preempt count (etc) right */
+ save_processor_state();
+ error = restore_highmem();
+ if (!error) {
+ error = swsusp_arch_resume();
+ /*
+ * The code below is only ever reached in case of a failure.
+ * Otherwise execution continues at place where
+ * swsusp_arch_suspend() was called
+ */
+ BUG_ON(!error);
+ /* This call to restore_highmem() undos the previous one */
+ restore_highmem();
+ }
+ /*
+ * The only reason why swsusp_arch_resume() can fail is memory being
+ * very tight, so we have to free it as soon as we can to avoid
+ * subsequent failures
+ */
+ swsusp_free();
+ restore_processor_state();
+ touch_softlockup_watchdog();
+
+ sysdev_resume();
+
+ Enable_irqs:
+ local_irq_enable();
+
+ Enable_cpus:
+ enable_nonboot_cpus();
+
+ Cleanup:
+ platform_restore_cleanup(platform_mode);
+
+ dpm_resume_noirq(PMSG_RECOVER);
+
+ return error;
+}
+
+/**
+ * hibernation_restore - quiesce devices and restore the hibernation
+ * snapshot image. If successful, control returns in hibernation_snaphot()
+ * @platform_mode - if set, use the platform driver, if available, to
+ * prepare the platform firmware for the transition.
+ *
+ * Must be called with pm_mutex held
+ */
+
+int hibernation_restore(int platform_mode)
+{
+ int error;
+
+ pm_prepare_console();
+ suspend_console();
+ error = dpm_suspend_start(PMSG_QUIESCE);
+ if (!error) {
+ error = resume_target_kernel(platform_mode);
+ dpm_resume_end(PMSG_RECOVER);
+ }
+ resume_console();
+ pm_restore_console();
+ return error;
+}
+
+/**
+ * hibernation_platform_enter - enter the hibernation state using the
+ * platform driver (if available)
+ */
+
+int hibernation_platform_enter(void)
+{
+ int error;
+
+ if (!hibernation_ops)
+ return -ENOSYS;
+
+ /*
+ * We have cancelled the power transition by running
+ * hibernation_ops->finish() before saving the image, so we should let
+ * the firmware know that we're going to enter the sleep state after all
+ */
+ error = hibernation_ops->begin();
+ if (error)
+ goto Close;
+
+ entering_platform_hibernation = true;
+ suspend_console();
+ error = dpm_suspend_start(PMSG_HIBERNATE);
+ if (error) {
+ if (hibernation_ops->recover)
+ hibernation_ops->recover();
+ goto Resume_devices;
+ }
+
+ error = dpm_suspend_noirq(PMSG_HIBERNATE);
+ if (error)
+ goto Resume_devices;
+
+ error = hibernation_ops->prepare();
+ if (error)
+ goto Platofrm_finish;
+
+ error = disable_nonboot_cpus();
+ if (error)
+ goto Platofrm_finish;
+
+ local_irq_disable();
+ sysdev_suspend(PMSG_HIBERNATE);
+ hibernation_ops->enter();
+ /* We should never get here */
+ while (1);
+
+ /*
+ * We don't need to reenable the nonboot CPUs or resume consoles, since
+ * the system is going to be halted anyway.
+ */
+ Platofrm_finish:
+ hibernation_ops->finish();
+
+ dpm_suspend_noirq(PMSG_RESTORE);
+
+ Resume_devices:
+ entering_platform_hibernation = false;
+ dpm_resume_end(PMSG_RESTORE);
+ resume_console();
+
+ Close:
+ hibernation_ops->end();
+
+ return error;
+}
+
+/**
+ * power_down - Shut the machine down for hibernation.
+ *
+ * Use the platform driver, if configured so; otherwise try
+ * to power off or reboot.
+ */
+
+static void power_down(void)
+{
+ switch (hibernation_mode) {
+ case HIBERNATION_TEST:
+ case HIBERNATION_TESTPROC:
+ break;
+ case HIBERNATION_REBOOT:
+ kernel_restart(NULL);
+ break;
+ case HIBERNATION_PLATFORM:
+ hibernation_platform_enter();
+ case HIBERNATION_SHUTDOWN:
+ kernel_power_off();
+ break;
+ }
+ kernel_halt();
+ /*
+ * Valid image is on the disk, if we continue we risk serious data
+ * corruption after resume.
+ */
+ printk(KERN_CRIT "PM: Please power down manually\n");
+ while(1);
+}
+
+static int prepare_processes(void)
+{
+ int error = 0;
+
+ if (freeze_processes()) {
+ error = -EBUSY;
+ thaw_processes();
+ }
+ return error;
+}
+
+/**
+ * hibernate - The granpappy of the built-in hibernation management
+ */
+
+int hibernate(void)
+{
+ int error;
+
+ mutex_lock(&pm_mutex);
+ /* The snapshot device should not be opened while we're running */
+ if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+ error = -EBUSY;
+ goto Unlock;
+ }
+
+ pm_prepare_console();
+ error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
+ if (error)
+ goto Exit;
+
+ error = usermodehelper_disable();
+ if (error)
+ goto Exit;
+
+ /* Allocate memory management structures */
+ error = create_basic_memory_bitmaps();
+ if (error)
+ goto Exit;
+
+ printk(KERN_INFO "PM: Syncing filesystems ... ");
+ sys_sync();
+ printk("done.\n");
+
+ error = prepare_processes();
+ if (error)
+ goto Finish;
+
+ if (hibernation_test(TEST_FREEZER))
+ goto Thaw;
+
+ if (hibernation_testmode(HIBERNATION_TESTPROC))
+ goto Thaw;
+
+ error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
+ if (in_suspend && !error) {
+ unsigned int flags = 0;
+
+ if (hibernation_mode == HIBERNATION_PLATFORM)
+ flags |= SF_PLATFORM_MODE;
+ pr_debug("PM: writing image.\n");
+ error = swsusp_write(flags);
+ swsusp_free();
+ if (!error)
+ power_down();
+ } else {
+ pr_debug("PM: Image restored successfully.\n");
+ swsusp_free();
+ }
+ Thaw:
+ thaw_processes();
+ Finish:
+ free_basic_memory_bitmaps();
+ usermodehelper_enable();
+ Exit:
+ pm_notifier_call_chain(PM_POST_HIBERNATION);
+ pm_restore_console();
+ atomic_inc(&snapshot_device_available);
+ Unlock:
+ mutex_unlock(&pm_mutex);
+ return error;
+}
+
+
+/**
+ * software_resume - Resume from a saved image.
+ *
+ * Called as a late_initcall (so all devices are discovered and
+ * initialized), we call swsusp to see if we have a saved image or not.
+ * If so, we quiesce devices, the restore the saved image. We will
+ * return above (in hibernate() ) if everything goes well.
+ * Otherwise, we fail gracefully and return to the normally
+ * scheduled program.
+ *
+ */
+
+static int software_resume(void)
+{
+ int error;
+ unsigned int flags;
+
+ /*
+ * If the user said "noresume".. bail out early.
+ */
+ if (noresume)
+ return 0;
+
+ /*
+ * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
+ * is configured into the kernel. Since the regular hibernate
+ * trigger path is via sysfs which takes a buffer mutex before
+ * calling hibernate functions (which take pm_mutex) this can
+ * cause lockdep to complain about a possible ABBA deadlock
+ * which cannot happen since we're in the boot code here and
+ * sysfs can't be invoked yet. Therefore, we use a subclass
+ * here to avoid lockdep complaining.
+ */
+ mutex_lock_nested(&pm_mutex, SINGLE_DEPTH_NESTING);
+
+ if (swsusp_resume_device)
+ goto Check_image;
+
+ if (!strlen(resume_file)) {
+ error = -ENOENT;
+ goto Unlock;
+ }
+
+ pr_debug("PM: Checking image partition %s\n", resume_file);
+
+ /* Check if the device is there */
+ swsusp_resume_device = name_to_dev_t(resume_file);
+ if (!swsusp_resume_device) {
+ /*
+ * Some device discovery might still be in progress; we need
+ * to wait for this to finish.
+ */
+ wait_for_device_probe();
+ /*
+ * We can't depend on SCSI devices being available after loading
+ * one of their modules until scsi_complete_async_scans() is
+ * called and the resume device usually is a SCSI one.
+ */
+ scsi_complete_async_scans();
+
+ swsusp_resume_device = name_to_dev_t(resume_file);
+ if (!swsusp_resume_device) {
+ error = -ENODEV;
+ goto Unlock;
+ }
+ }
+
+ Check_image:
+ pr_debug("PM: Resume from partition %d:%d\n",
+ MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
+
+ pr_debug("PM: Checking hibernation image.\n");
+ error = swsusp_check();
+ if (error)
+ goto Unlock;
+
+ /* The snapshot device should not be opened while we're running */
+ if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+ error = -EBUSY;
+ goto Unlock;
+ }
+
+ pm_prepare_console();
+ error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
+ if (error)
+ goto Finish;
+
+ error = usermodehelper_disable();
+ if (error)
+ goto Finish;
+
+ error = create_basic_memory_bitmaps();
+ if (error)
+ goto Finish;
+
+ pr_debug("PM: Preparing processes for restore.\n");
+ error = prepare_processes();
+ if (error) {
+ swsusp_close(FMODE_READ);
+ goto Done;
+ }
+
+ pr_debug("PM: Reading hibernation image.\n");
+
+ error = swsusp_read(&flags);
+ if (!error)
+ hibernation_restore(flags & SF_PLATFORM_MODE);
+
+ printk(KERN_ERR "PM: Restore failed, recovering.\n");
+ swsusp_free();
+ thaw_processes();
+ Done:
+ free_basic_memory_bitmaps();
+ usermodehelper_enable();
+ Finish:
+ pm_notifier_call_chain(PM_POST_RESTORE);
+ pm_restore_console();
+ atomic_inc(&snapshot_device_available);
+ /* For success case, the suspend path will release the lock */
+ Unlock:
+ mutex_unlock(&pm_mutex);
+ pr_debug("PM: Resume from disk failed.\n");
+ return error;
+}
+
+late_initcall(software_resume);
+
+
+static const char * const hibernation_modes[] = {
+ [HIBERNATION_PLATFORM] = "platform",
+ [HIBERNATION_SHUTDOWN] = "shutdown",
+ [HIBERNATION_REBOOT] = "reboot",
+ [HIBERNATION_TEST] = "test",
+ [HIBERNATION_TESTPROC] = "testproc",
+};
+
+/**
+ * disk - Control hibernation mode
+ *
+ * Suspend-to-disk can be handled in several ways. We have a few options
+ * for putting the system to sleep - using the platform driver (e.g. ACPI
+ * or other hibernation_ops), powering off the system or rebooting the
+ * system (for testing) as well as the two test modes.
+ *
+ * The system can support 'platform', and that is known a priori (and
+ * encoded by the presence of hibernation_ops). However, the user may
+ * choose 'shutdown' or 'reboot' as alternatives, as well as one fo the
+ * test modes, 'test' or 'testproc'.
+ *
+ * show() will display what the mode is currently set to.
+ * store() will accept one of
+ *
+ * 'platform'
+ * 'shutdown'
+ * 'reboot'
+ * 'test'
+ * 'testproc'
+ *
+ * It will only change to 'platform' if the system
+ * supports it (as determined by having hibernation_ops).
+ */
+
+static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ int i;
+ char *start = buf;
+
+ for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
+ if (!hibernation_modes[i])
+ continue;
+ switch (i) {
+ case HIBERNATION_SHUTDOWN:
+ case HIBERNATION_REBOOT:
+ case HIBERNATION_TEST:
+ case HIBERNATION_TESTPROC:
+ break;
+ case HIBERNATION_PLATFORM:
+ if (hibernation_ops)
+ break;
+ /* not a valid mode, continue with loop */
+ continue;
+ }
+ if (i == hibernation_mode)
+ buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
+ else
+ buf += sprintf(buf, "%s ", hibernation_modes[i]);
+ }
+ buf += sprintf(buf, "\n");
+ return buf-start;
+}
+
+
+static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ int error = 0;
+ int i;
+ int len;
+ char *p;
+ int mode = HIBERNATION_INVALID;
+
+ p = memchr(buf, '\n', n);
+ len = p ? p - buf : n;
+
+ mutex_lock(&pm_mutex);
+ for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
+ if (len == strlen(hibernation_modes[i])
+ && !strncmp(buf, hibernation_modes[i], len)) {
+ mode = i;
+ break;
+ }
+ }
+ if (mode != HIBERNATION_INVALID) {
+ switch (mode) {
+ case HIBERNATION_SHUTDOWN:
+ case HIBERNATION_REBOOT:
+ case HIBERNATION_TEST:
+ case HIBERNATION_TESTPROC:
+ hibernation_mode = mode;
+ break;
+ case HIBERNATION_PLATFORM:
+ if (hibernation_ops)
+ hibernation_mode = mode;
+ else
+ error = -EINVAL;
+ }
+ } else
+ error = -EINVAL;
+
+ if (!error)
+ pr_debug("PM: Hibernation mode set to '%s'\n",
+ hibernation_modes[mode]);
+ mutex_unlock(&pm_mutex);
+ return error ? error : n;
+}
+
+power_attr(disk);
+
+static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
+ MINOR(swsusp_resume_device));
+}
+
+static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ unsigned int maj, min;
+ dev_t res;
+ int ret = -EINVAL;
+
+ if (sscanf(buf, "%u:%u", &maj, &min) != 2)
+ goto out;
+
+ res = MKDEV(maj,min);
+ if (maj != MAJOR(res) || min != MINOR(res))
+ goto out;
+
+ mutex_lock(&pm_mutex);
+ swsusp_resume_device = res;
+ mutex_unlock(&pm_mutex);
+ printk(KERN_INFO "PM: Starting manual resume from disk\n");
+ noresume = 0;
+ software_resume();
+ ret = n;
+ out:
+ return ret;
+}
+
+power_attr(resume);
+
+static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%lu\n", image_size);
+}
+
+static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ unsigned long size;
+
+ if (sscanf(buf, "%lu", &size) == 1) {
+ image_size = size;
+ return n;
+ }
+
+ return -EINVAL;
+}
+
+power_attr(image_size);
+
+static struct attribute * g[] = {
+ &disk_attr.attr,
+ &resume_attr.attr,
+ &image_size_attr.attr,
+ NULL,
+};
+
+
+static struct attribute_group attr_group = {
+ .attrs = g,
+};
+
+
+static int __init pm_disk_init(void)
+{
+ return sysfs_create_group(power_kobj, &attr_group);
+}
+
+core_initcall(pm_disk_init);
+
+
+static int __init resume_setup(char *str)
+{
+ if (noresume)
+ return 1;
+
+ strncpy( resume_file, str, 255 );
+ return 1;
+}
+
+static int __init resume_offset_setup(char *str)
+{
+ unsigned long long offset;
+
+ if (noresume)
+ return 1;
+
+ if (sscanf(str, "%llu", &offset) == 1)
+ swsusp_resume_block = offset;
+
+ return 1;
+}
+
+static int __init noresume_setup(char *str)
+{
+ noresume = 1;
+ return 1;
+}
+
+__setup("noresume", noresume_setup);
+__setup("resume_offset=", resume_offset_setup);
+__setup("resume=", resume_setup);