/*
|
* 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@ucw.cz>
|
* Copyright (c) 2009 Rafael J. Wysocki, Novell Inc.
|
* Copyright (C) 2012 Bojan Smojver <bojan@rexursive.com>
|
*
|
* This file is released under the GPLv2.
|
*/
|
|
#define pr_fmt(fmt) "PM: " fmt
|
|
#include <linux/export.h>
|
#include <linux/suspend.h>
|
#include <linux/syscalls.h>
|
#include <linux/reboot.h>
|
#include <linux/string.h>
|
#include <linux/device.h>
|
#include <linux/async.h>
|
#include <linux/delay.h>
|
#include <linux/fs.h>
|
#include <linux/mount.h>
|
#include <linux/pm.h>
|
#include <linux/nmi.h>
|
#include <linux/console.h>
|
#include <linux/cpu.h>
|
#include <linux/freezer.h>
|
#include <linux/gfp.h>
|
#include <linux/syscore_ops.h>
|
#include <linux/ctype.h>
|
#include <linux/genhd.h>
|
#include <linux/ktime.h>
|
#include <trace/events/power.h>
|
|
#include "power.h"
|
|
|
static int nocompress;
|
static int noresume;
|
static int nohibernate;
|
static int resume_wait;
|
static unsigned int resume_delay;
|
static char resume_file[256] = CONFIG_PM_STD_PARTITION;
|
dev_t swsusp_resume_device;
|
sector_t swsusp_resume_block;
|
__visible int in_suspend __nosavedata;
|
|
enum {
|
HIBERNATION_INVALID,
|
HIBERNATION_PLATFORM,
|
HIBERNATION_SHUTDOWN,
|
HIBERNATION_REBOOT,
|
#ifdef CONFIG_SUSPEND
|
HIBERNATION_SUSPEND,
|
#endif
|
HIBERNATION_TEST_RESUME,
|
/* keep last */
|
__HIBERNATION_AFTER_LAST
|
};
|
#define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
|
#define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
|
|
static int hibernation_mode = HIBERNATION_SHUTDOWN;
|
|
bool freezer_test_done;
|
|
static const struct platform_hibernation_ops *hibernation_ops;
|
|
bool hibernation_available(void)
|
{
|
return (nohibernate == 0);
|
}
|
|
/**
|
* hibernation_set_ops - Set the global hibernate operations.
|
* @ops: Hibernation operations to use in subsequent hibernation transitions.
|
*/
|
void hibernation_set_ops(const 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 && ops->leave)) {
|
WARN_ON(1);
|
return;
|
}
|
lock_system_sleep();
|
hibernation_ops = ops;
|
if (ops)
|
hibernation_mode = HIBERNATION_PLATFORM;
|
else if (hibernation_mode == HIBERNATION_PLATFORM)
|
hibernation_mode = HIBERNATION_SHUTDOWN;
|
|
unlock_system_sleep();
|
}
|
EXPORT_SYMBOL_GPL(hibernation_set_ops);
|
|
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)
|
{
|
pr_info("hibernation debug: Waiting for 5 seconds.\n");
|
mdelay(5000);
|
}
|
|
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_test(int level) { return 0; }
|
#endif /* !CONFIG_PM_DEBUG */
|
|
/**
|
* platform_begin - Call platform to start hibernation.
|
* @platform_mode: Whether or not to use the platform driver.
|
*/
|
static int platform_begin(int platform_mode)
|
{
|
return (platform_mode && hibernation_ops) ?
|
hibernation_ops->begin() : 0;
|
}
|
|
/**
|
* platform_end - Call platform to finish transition to the working state.
|
* @platform_mode: Whether or not to use the platform driver.
|
*/
|
static void platform_end(int platform_mode)
|
{
|
if (platform_mode && hibernation_ops)
|
hibernation_ops->end();
|
}
|
|
/**
|
* platform_pre_snapshot - Call platform to prepare the machine for hibernation.
|
* @platform_mode: Whether or not to use the platform driver.
|
*
|
* Use the platform driver to prepare the system for creating a hibernate image,
|
* if so configured, and return an error code if that fails.
|
*/
|
|
static int platform_pre_snapshot(int platform_mode)
|
{
|
return (platform_mode && hibernation_ops) ?
|
hibernation_ops->pre_snapshot() : 0;
|
}
|
|
/**
|
* platform_leave - Call platform to prepare a transition to the working state.
|
* @platform_mode: Whether or not to use the platform driver.
|
*
|
* Use the platform driver prepare to prepare the machine for switching to the
|
* normal mode of operation.
|
*
|
* This routine is called on one CPU with interrupts disabled.
|
*/
|
static void platform_leave(int platform_mode)
|
{
|
if (platform_mode && hibernation_ops)
|
hibernation_ops->leave();
|
}
|
|
/**
|
* platform_finish - Call platform to switch the system to the working state.
|
* @platform_mode: Whether or not to use the platform driver.
|
*
|
* Use the platform driver to switch the machine to the normal mode of
|
* operation.
|
*
|
* This routine 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 for hibernate image restoration.
|
* @platform_mode: Whether or not to use the platform driver.
|
*
|
* Use the platform driver to prepare the system for resume 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 to the working state after failing restore.
|
* @platform_mode: Whether or not to use the platform driver.
|
*
|
* Use the platform driver to switch the system 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 from a failure to suspend devices.
|
* @platform_mode: Whether or not to use the platform driver.
|
*/
|
static void platform_recover(int platform_mode)
|
{
|
if (platform_mode && hibernation_ops && hibernation_ops->recover)
|
hibernation_ops->recover();
|
}
|
|
/**
|
* swsusp_show_speed - Print time elapsed between two events during hibernation.
|
* @start: Starting event.
|
* @stop: Final event.
|
* @nr_pages: Number of memory pages processed between @start and @stop.
|
* @msg: Additional diagnostic message to print.
|
*/
|
void swsusp_show_speed(ktime_t start, ktime_t stop,
|
unsigned nr_pages, char *msg)
|
{
|
ktime_t diff;
|
u64 elapsed_centisecs64;
|
unsigned int centisecs;
|
unsigned int k;
|
unsigned int kps;
|
|
diff = ktime_sub(stop, start);
|
elapsed_centisecs64 = ktime_divns(diff, 10*NSEC_PER_MSEC);
|
centisecs = elapsed_centisecs64;
|
if (centisecs == 0)
|
centisecs = 1; /* avoid div-by-zero */
|
k = nr_pages * (PAGE_SIZE / 1024);
|
kps = (k * 100) / centisecs;
|
pr_info("%s %u kbytes in %u.%02u seconds (%u.%02u MB/s)\n",
|
msg, k, centisecs / 100, centisecs % 100, kps / 1000,
|
(kps % 1000) / 10);
|
}
|
|
__weak int arch_resume_nosmt(void)
|
{
|
return 0;
|
}
|
|
/**
|
* create_image - Create a hibernation image.
|
* @platform_mode: Whether or not to use the platform driver.
|
*
|
* Execute device drivers' "late" and "noirq" freeze callbacks, create a
|
* hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
|
*
|
* Control reappears in this routine after the subsequent restore.
|
*/
|
static int create_image(int platform_mode)
|
{
|
int error;
|
|
error = dpm_suspend_end(PMSG_FREEZE);
|
if (error) {
|
pr_err("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))
|
goto Enable_cpus;
|
|
local_irq_disable();
|
|
system_state = SYSTEM_SUSPEND;
|
|
error = syscore_suspend();
|
if (error) {
|
pr_err("Some system devices failed to power down, aborting hibernation\n");
|
goto Enable_irqs;
|
}
|
|
if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
|
goto Power_up;
|
|
in_suspend = 1;
|
save_processor_state();
|
trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true);
|
error = swsusp_arch_suspend();
|
/* Restore control flow magically appears here */
|
restore_processor_state();
|
trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false);
|
if (error)
|
pr_err("Error %d creating hibernation image\n", error);
|
|
if (!in_suspend) {
|
events_check_enabled = false;
|
clear_free_pages();
|
}
|
|
platform_leave(platform_mode);
|
|
Power_up:
|
syscore_resume();
|
|
Enable_irqs:
|
system_state = SYSTEM_RUNNING;
|
local_irq_enable();
|
|
Enable_cpus:
|
enable_nonboot_cpus();
|
|
/* Allow architectures to do nosmt-specific post-resume dances */
|
if (!in_suspend)
|
error = arch_resume_nosmt();
|
|
Platform_finish:
|
platform_finish(platform_mode);
|
|
dpm_resume_start(in_suspend ?
|
(error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
|
|
return error;
|
}
|
|
/**
|
* hibernation_snapshot - Quiesce devices and create a hibernation image.
|
* @platform_mode: If set, use platform driver to prepare for the transition.
|
*
|
* This routine must be called with system_transition_mutex held.
|
*/
|
int hibernation_snapshot(int platform_mode)
|
{
|
pm_message_t msg;
|
int error;
|
|
pm_suspend_clear_flags();
|
error = platform_begin(platform_mode);
|
if (error)
|
goto Close;
|
|
/* Preallocate image memory before shutting down devices. */
|
error = hibernate_preallocate_memory();
|
if (error)
|
goto Close;
|
|
error = freeze_kernel_threads();
|
if (error)
|
goto Cleanup;
|
|
if (hibernation_test(TEST_FREEZER)) {
|
|
/*
|
* Indicate to the caller that we are returning due to a
|
* successful freezer test.
|
*/
|
freezer_test_done = true;
|
goto Thaw;
|
}
|
|
error = dpm_prepare(PMSG_FREEZE);
|
if (error) {
|
dpm_complete(PMSG_RECOVER);
|
goto Thaw;
|
}
|
|
suspend_console();
|
pm_restrict_gfp_mask();
|
|
error = dpm_suspend(PMSG_FREEZE);
|
|
if (error || hibernation_test(TEST_DEVICES))
|
platform_recover(platform_mode);
|
else
|
error = create_image(platform_mode);
|
|
/*
|
* In the case that we call create_image() above, the control
|
* returns here (1) after the image has been created or the
|
* image creation has failed and (2) after a successful restore.
|
*/
|
|
/* We may need to release the preallocated image pages here. */
|
if (error || !in_suspend)
|
swsusp_free();
|
|
msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
|
dpm_resume(msg);
|
|
if (error || !in_suspend)
|
pm_restore_gfp_mask();
|
|
resume_console();
|
dpm_complete(msg);
|
|
Close:
|
platform_end(platform_mode);
|
return error;
|
|
Thaw:
|
thaw_kernel_threads();
|
Cleanup:
|
swsusp_free();
|
goto Close;
|
}
|
|
int __weak hibernate_resume_nonboot_cpu_disable(void)
|
{
|
return disable_nonboot_cpus();
|
}
|
|
/**
|
* resume_target_kernel - Restore system state from a hibernation image.
|
* @platform_mode: Whether or not to use the platform driver.
|
*
|
* Execute device drivers' "noirq" and "late" freeze callbacks, 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_end(PMSG_QUIESCE);
|
if (error) {
|
pr_err("Some devices failed to power down, aborting resume\n");
|
return error;
|
}
|
|
error = platform_pre_restore(platform_mode);
|
if (error)
|
goto Cleanup;
|
|
error = hibernate_resume_nonboot_cpu_disable();
|
if (error)
|
goto Enable_cpus;
|
|
local_irq_disable();
|
system_state = SYSTEM_SUSPEND;
|
|
error = syscore_suspend();
|
if (error)
|
goto Enable_irqs;
|
|
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 the place where
|
* swsusp_arch_suspend() was called.
|
*/
|
BUG_ON(!error);
|
/*
|
* This call to restore_highmem() reverts the changes made by
|
* 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();
|
|
syscore_resume();
|
|
Enable_irqs:
|
system_state = SYSTEM_RUNNING;
|
local_irq_enable();
|
|
Enable_cpus:
|
enable_nonboot_cpus();
|
|
Cleanup:
|
platform_restore_cleanup(platform_mode);
|
|
dpm_resume_start(PMSG_RECOVER);
|
|
return error;
|
}
|
|
/**
|
* hibernation_restore - Quiesce devices and restore from a hibernation image.
|
* @platform_mode: If set, use platform driver to prepare for the transition.
|
*
|
* This routine must be called with system_transition_mutex held. If it is
|
* successful, control reappears in the restored target kernel in
|
* hibernation_snapshot().
|
*/
|
int hibernation_restore(int platform_mode)
|
{
|
int error;
|
|
pm_prepare_console();
|
suspend_console();
|
pm_restrict_gfp_mask();
|
error = dpm_suspend_start(PMSG_QUIESCE);
|
if (!error) {
|
error = resume_target_kernel(platform_mode);
|
/*
|
* The above should either succeed and jump to the new kernel,
|
* or return with an error. Otherwise things are just
|
* undefined, so let's be paranoid.
|
*/
|
BUG_ON(!error);
|
}
|
dpm_resume_end(PMSG_RECOVER);
|
pm_restore_gfp_mask();
|
resume_console();
|
pm_restore_console();
|
return error;
|
}
|
|
/**
|
* hibernation_platform_enter - Power off the system using the platform driver.
|
*/
|
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_end(PMSG_HIBERNATE);
|
if (error)
|
goto Resume_devices;
|
|
error = hibernation_ops->prepare();
|
if (error)
|
goto Platform_finish;
|
|
error = disable_nonboot_cpus();
|
if (error)
|
goto Enable_cpus;
|
|
local_irq_disable();
|
system_state = SYSTEM_SUSPEND;
|
syscore_suspend();
|
if (pm_wakeup_pending()) {
|
error = -EAGAIN;
|
goto Power_up;
|
}
|
|
hibernation_ops->enter();
|
/* We should never get here */
|
while (1);
|
|
Power_up:
|
syscore_resume();
|
system_state = SYSTEM_RUNNING;
|
local_irq_enable();
|
|
Enable_cpus:
|
enable_nonboot_cpus();
|
|
Platform_finish:
|
hibernation_ops->finish();
|
|
dpm_resume_start(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, to put the system into the sleep
|
* state corresponding to hibernation, or try to power it off or reboot,
|
* depending on the value of hibernation_mode.
|
*/
|
static void power_down(void)
|
{
|
#ifdef CONFIG_SUSPEND
|
int error;
|
|
if (hibernation_mode == HIBERNATION_SUSPEND) {
|
error = suspend_devices_and_enter(PM_SUSPEND_MEM);
|
if (error) {
|
hibernation_mode = hibernation_ops ?
|
HIBERNATION_PLATFORM :
|
HIBERNATION_SHUTDOWN;
|
} else {
|
/* Restore swap signature. */
|
error = swsusp_unmark();
|
if (error)
|
pr_err("Swap will be unusable! Try swapon -a.\n");
|
|
return;
|
}
|
}
|
#endif
|
|
switch (hibernation_mode) {
|
case HIBERNATION_REBOOT:
|
kernel_restart(NULL);
|
break;
|
case HIBERNATION_PLATFORM:
|
hibernation_platform_enter();
|
/* Fall through */
|
case HIBERNATION_SHUTDOWN:
|
if (pm_power_off)
|
kernel_power_off();
|
break;
|
}
|
kernel_halt();
|
/*
|
* Valid image is on the disk, if we continue we risk serious data
|
* corruption after resume.
|
*/
|
pr_crit("Power down manually\n");
|
while (1)
|
cpu_relax();
|
}
|
|
static int load_image_and_restore(void)
|
{
|
int error;
|
unsigned int flags;
|
|
pm_pr_dbg("Loading hibernation image.\n");
|
|
lock_device_hotplug();
|
error = create_basic_memory_bitmaps();
|
if (error)
|
goto Unlock;
|
|
error = swsusp_read(&flags);
|
swsusp_close(FMODE_READ | FMODE_EXCL);
|
if (!error)
|
hibernation_restore(flags & SF_PLATFORM_MODE);
|
|
pr_err("Failed to load hibernation image, recovering.\n");
|
swsusp_free();
|
free_basic_memory_bitmaps();
|
Unlock:
|
unlock_device_hotplug();
|
|
return error;
|
}
|
|
#ifndef CONFIG_SUSPEND
|
bool pm_in_action;
|
#endif
|
|
/**
|
* hibernate - Carry out system hibernation, including saving the image.
|
*/
|
int hibernate(void)
|
{
|
int error, nr_calls = 0;
|
bool snapshot_test = false;
|
|
if (!hibernation_available()) {
|
pm_pr_dbg("Hibernation not available.\n");
|
return -EPERM;
|
}
|
|
pm_in_action = true;
|
|
lock_system_sleep();
|
/* The snapshot device should not be opened while we're running */
|
if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
|
error = -EBUSY;
|
goto Unlock;
|
}
|
|
pr_info("hibernation entry\n");
|
pm_prepare_console();
|
error = __pm_notifier_call_chain(PM_HIBERNATION_PREPARE, -1, &nr_calls);
|
if (error) {
|
nr_calls--;
|
goto Exit;
|
}
|
|
pr_info("Syncing filesystems ... \n");
|
ksys_sync();
|
pr_info("done.\n");
|
|
error = freeze_processes();
|
if (error)
|
goto Exit;
|
|
lock_device_hotplug();
|
/* Allocate memory management structures */
|
error = create_basic_memory_bitmaps();
|
if (error)
|
goto Thaw;
|
|
error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
|
if (error || freezer_test_done)
|
goto Free_bitmaps;
|
|
if (in_suspend) {
|
unsigned int flags = 0;
|
|
if (hibernation_mode == HIBERNATION_PLATFORM)
|
flags |= SF_PLATFORM_MODE;
|
if (nocompress)
|
flags |= SF_NOCOMPRESS_MODE;
|
else
|
flags |= SF_CRC32_MODE;
|
|
pm_pr_dbg("Writing image.\n");
|
error = swsusp_write(flags);
|
swsusp_free();
|
if (!error) {
|
if (hibernation_mode == HIBERNATION_TEST_RESUME)
|
snapshot_test = true;
|
else
|
power_down();
|
}
|
in_suspend = 0;
|
pm_restore_gfp_mask();
|
} else {
|
pm_pr_dbg("Image restored successfully.\n");
|
}
|
|
Free_bitmaps:
|
free_basic_memory_bitmaps();
|
Thaw:
|
unlock_device_hotplug();
|
if (snapshot_test) {
|
pm_pr_dbg("Checking hibernation image\n");
|
error = swsusp_check();
|
if (!error)
|
error = load_image_and_restore();
|
}
|
thaw_processes();
|
|
/* Don't bother checking whether freezer_test_done is true */
|
freezer_test_done = false;
|
Exit:
|
__pm_notifier_call_chain(PM_POST_HIBERNATION, nr_calls, NULL);
|
pm_restore_console();
|
atomic_inc(&snapshot_device_available);
|
Unlock:
|
unlock_system_sleep();
|
pm_in_action = false;
|
pr_info("hibernation exit\n");
|
|
return error;
|
}
|
|
|
/**
|
* software_resume - Resume from a saved hibernation image.
|
*
|
* This routine is called as a late initcall, when all devices have been
|
* discovered and initialized already.
|
*
|
* The image reading code is called to see if there is a hibernation image
|
* available for reading. If that is the case, devices are quiesced and the
|
* contents of memory is restored from the saved image.
|
*
|
* If this is successful, control reappears in the restored target kernel in
|
* hibernation_snapshot() which returns to hibernate(). Otherwise, the routine
|
* attempts to recover gracefully and make the kernel return to the normal mode
|
* of operation.
|
*/
|
static int software_resume(void)
|
{
|
int error, nr_calls = 0;
|
|
/*
|
* If the user said "noresume".. bail out early.
|
*/
|
if (noresume || !hibernation_available())
|
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 system_transition_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(&system_transition_mutex, SINGLE_DEPTH_NESTING);
|
|
if (swsusp_resume_device)
|
goto Check_image;
|
|
if (!strlen(resume_file)) {
|
error = -ENOENT;
|
goto Unlock;
|
}
|
|
pm_pr_dbg("Checking hibernation image partition %s\n", resume_file);
|
|
if (resume_delay) {
|
pr_info("Waiting %dsec before reading resume device ...\n",
|
resume_delay);
|
ssleep(resume_delay);
|
}
|
|
/* 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();
|
|
if (resume_wait) {
|
while ((swsusp_resume_device = name_to_dev_t(resume_file)) == 0)
|
msleep(10);
|
async_synchronize_full();
|
}
|
|
swsusp_resume_device = name_to_dev_t(resume_file);
|
if (!swsusp_resume_device) {
|
error = -ENODEV;
|
goto Unlock;
|
}
|
}
|
|
Check_image:
|
pm_pr_dbg("Hibernation image partition %d:%d present\n",
|
MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
|
|
pm_pr_dbg("Looking for 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;
|
swsusp_close(FMODE_READ | FMODE_EXCL);
|
goto Unlock;
|
}
|
|
pr_info("resume from hibernation\n");
|
pm_prepare_console();
|
error = __pm_notifier_call_chain(PM_RESTORE_PREPARE, -1, &nr_calls);
|
if (error) {
|
nr_calls--;
|
goto Close_Finish;
|
}
|
|
pm_pr_dbg("Preparing processes for restore.\n");
|
error = freeze_processes();
|
if (error)
|
goto Close_Finish;
|
|
error = freeze_kernel_threads();
|
if (error) {
|
thaw_processes();
|
goto Close_Finish;
|
}
|
|
error = load_image_and_restore();
|
thaw_processes();
|
Finish:
|
__pm_notifier_call_chain(PM_POST_RESTORE, nr_calls, NULL);
|
pm_restore_console();
|
pr_info("resume from hibernation failed (%d)\n", error);
|
atomic_inc(&snapshot_device_available);
|
/* For success case, the suspend path will release the lock */
|
Unlock:
|
mutex_unlock(&system_transition_mutex);
|
pm_pr_dbg("Hibernation image not present or could not be loaded.\n");
|
return error;
|
Close_Finish:
|
swsusp_close(FMODE_READ | FMODE_EXCL);
|
goto Finish;
|
}
|
|
late_initcall_sync(software_resume);
|
|
|
static const char * const hibernation_modes[] = {
|
[HIBERNATION_PLATFORM] = "platform",
|
[HIBERNATION_SHUTDOWN] = "shutdown",
|
[HIBERNATION_REBOOT] = "reboot",
|
#ifdef CONFIG_SUSPEND
|
[HIBERNATION_SUSPEND] = "suspend",
|
#endif
|
[HIBERNATION_TEST_RESUME] = "test_resume",
|
};
|
|
/*
|
* /sys/power/disk - Control hibernation mode.
|
*
|
* Hibernation can be handled in several ways. There are a few different ways
|
* to put the system into the sleep state: using the platform driver (e.g. ACPI
|
* or other hibernation_ops), powering it off or rebooting it (for testing
|
* mostly).
|
*
|
* The sysfs file /sys/power/disk provides an interface for selecting the
|
* hibernation mode to use. Reading from this file causes the available modes
|
* to be printed. There are 3 modes that can be supported:
|
*
|
* 'platform'
|
* 'shutdown'
|
* 'reboot'
|
*
|
* If a platform hibernation driver is in use, 'platform' will be supported
|
* and will be used by default. Otherwise, 'shutdown' will be used by default.
|
* The selected option (i.e. the one corresponding to the current value of
|
* hibernation_mode) is enclosed by a square bracket.
|
*
|
* To select a given hibernation mode it is necessary to write the mode's
|
* string representation (as returned by reading from /sys/power/disk) back
|
* into /sys/power/disk.
|
*/
|
|
static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
|
char *buf)
|
{
|
int i;
|
char *start = buf;
|
|
if (!hibernation_available())
|
return sprintf(buf, "[disabled]\n");
|
|
for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
|
if (!hibernation_modes[i])
|
continue;
|
switch (i) {
|
case HIBERNATION_SHUTDOWN:
|
case HIBERNATION_REBOOT:
|
#ifdef CONFIG_SUSPEND
|
case HIBERNATION_SUSPEND:
|
#endif
|
case HIBERNATION_TEST_RESUME:
|
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;
|
|
if (!hibernation_available())
|
return -EPERM;
|
|
p = memchr(buf, '\n', n);
|
len = p ? p - buf : n;
|
|
lock_system_sleep();
|
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:
|
#ifdef CONFIG_SUSPEND
|
case HIBERNATION_SUSPEND:
|
#endif
|
case HIBERNATION_TEST_RESUME:
|
hibernation_mode = mode;
|
break;
|
case HIBERNATION_PLATFORM:
|
if (hibernation_ops)
|
hibernation_mode = mode;
|
else
|
error = -EINVAL;
|
}
|
} else
|
error = -EINVAL;
|
|
if (!error)
|
pm_pr_dbg("Hibernation mode set to '%s'\n",
|
hibernation_modes[mode]);
|
unlock_system_sleep();
|
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)
|
{
|
dev_t res;
|
int len = n;
|
char *name;
|
|
if (len && buf[len-1] == '\n')
|
len--;
|
name = kstrndup(buf, len, GFP_KERNEL);
|
if (!name)
|
return -ENOMEM;
|
|
res = name_to_dev_t(name);
|
kfree(name);
|
if (!res)
|
return -EINVAL;
|
|
lock_system_sleep();
|
swsusp_resume_device = res;
|
unlock_system_sleep();
|
pm_pr_dbg("Configured resume from disk to %u\n", swsusp_resume_device);
|
noresume = 0;
|
software_resume();
|
return n;
|
}
|
|
power_attr(resume);
|
|
static ssize_t resume_offset_show(struct kobject *kobj,
|
struct kobj_attribute *attr, char *buf)
|
{
|
return sprintf(buf, "%llu\n", (unsigned long long)swsusp_resume_block);
|
}
|
|
static ssize_t resume_offset_store(struct kobject *kobj,
|
struct kobj_attribute *attr, const char *buf,
|
size_t n)
|
{
|
unsigned long long offset;
|
int rc;
|
|
rc = kstrtoull(buf, 0, &offset);
|
if (rc)
|
return rc;
|
swsusp_resume_block = offset;
|
|
return n;
|
}
|
|
power_attr(resume_offset);
|
|
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 ssize_t reserved_size_show(struct kobject *kobj,
|
struct kobj_attribute *attr, char *buf)
|
{
|
return sprintf(buf, "%lu\n", reserved_size);
|
}
|
|
static ssize_t reserved_size_store(struct kobject *kobj,
|
struct kobj_attribute *attr,
|
const char *buf, size_t n)
|
{
|
unsigned long size;
|
|
if (sscanf(buf, "%lu", &size) == 1) {
|
reserved_size = size;
|
return n;
|
}
|
|
return -EINVAL;
|
}
|
|
power_attr(reserved_size);
|
|
static struct attribute * g[] = {
|
&disk_attr.attr,
|
&resume_offset_attr.attr,
|
&resume_attr.attr,
|
&image_size_attr.attr,
|
&reserved_size_attr.attr,
|
NULL,
|
};
|
|
|
static const 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 hibernate_setup(char *str)
|
{
|
if (!strncmp(str, "noresume", 8)) {
|
noresume = 1;
|
} else if (!strncmp(str, "nocompress", 10)) {
|
nocompress = 1;
|
} else if (!strncmp(str, "no", 2)) {
|
noresume = 1;
|
nohibernate = 1;
|
} else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)
|
&& !strncmp(str, "protect_image", 13)) {
|
enable_restore_image_protection();
|
}
|
return 1;
|
}
|
|
static int __init noresume_setup(char *str)
|
{
|
noresume = 1;
|
return 1;
|
}
|
|
static int __init resumewait_setup(char *str)
|
{
|
resume_wait = 1;
|
return 1;
|
}
|
|
static int __init resumedelay_setup(char *str)
|
{
|
int rc = kstrtouint(str, 0, &resume_delay);
|
|
if (rc)
|
return rc;
|
return 1;
|
}
|
|
static int __init nohibernate_setup(char *str)
|
{
|
noresume = 1;
|
nohibernate = 1;
|
return 1;
|
}
|
|
__setup("noresume", noresume_setup);
|
__setup("resume_offset=", resume_offset_setup);
|
__setup("resume=", resume_setup);
|
__setup("hibernate=", hibernate_setup);
|
__setup("resumewait", resumewait_setup);
|
__setup("resumedelay=", resumedelay_setup);
|
__setup("nohibernate", nohibernate_setup);
|
