kernel_optimize_test/kernel/power/disk.c
Rafael J. Wysocki 74f270af0c PM: Rework struct hibernation_ops
During hibernation we also need to tell the ACPI core that we're going to put
the system into the S4 sleep state.  For this reason, an additional method in
'struct hibernation_ops' is needed, playing the role of set_target() in
'struct platform_suspend_operations'.  Moreover, the role of the .prepare()
method is now different, so it's better to introduce another method, that in
general may be different from .prepare(), that will be used to prepare the
platform for creating the hibernation image (.prepare() is used anyway to
notify the platform that we're going to enter the low power state after the
image has been saved).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 14:37:18 -07:00

649 lines
14 KiB
C

/*
* kernel/power/disk.c - Suspend-to-disk support.
*
* Copyright (c) 2003 Patrick Mochel
* Copyright (c) 2003 Open Source Development Lab
* Copyright (c) 2004 Pavel Machek <pavel@suse.cz>
*
* 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/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 "power.h"
static int noresume = 0;
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 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 hibernation_ops *ops)
{
if (ops && !(ops->start && ops->pre_snapshot && ops->finish
&& ops->prepare && 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);
}
/**
* platform_start - tell the platform driver that we're starting
* hibernation
*/
static int platform_start(int platform_mode)
{
return (platform_mode && hibernation_ops) ?
hibernation_ops->start() : 0;
}
/**
* 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_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();
}
/**
* hibernation_snapshot - quiesce devices and create the hibernation
* snapshot image.
* @platform_mode - if set, use the platform driver, if available, to
* prepare the platform frimware for the power transition.
*
* Must be called with pm_mutex held
*/
int hibernation_snapshot(int platform_mode)
{
int error;
/* Free memory before shutting down devices. */
error = swsusp_shrink_memory();
if (error)
return error;
error = platform_start(platform_mode);
if (error)
return error;
suspend_console();
error = device_suspend(PMSG_FREEZE);
if (error)
goto Resume_console;
error = platform_pre_snapshot(platform_mode);
if (error)
goto Resume_devices;
error = disable_nonboot_cpus();
if (!error) {
if (hibernation_mode != HIBERNATION_TEST) {
in_suspend = 1;
error = swsusp_suspend();
/* Control returns here after successful restore */
} else {
printk("swsusp debug: Waiting for 5 seconds.\n");
mdelay(5000);
}
}
enable_nonboot_cpus();
Resume_devices:
platform_finish(platform_mode);
device_resume();
Resume_console:
resume_console();
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 frimware for the transition.
*
* Must be called with pm_mutex held
*/
int hibernation_restore(int platform_mode)
{
int error;
pm_prepare_console();
suspend_console();
error = device_suspend(PMSG_PRETHAW);
if (error)
goto Finish;
error = platform_pre_restore(platform_mode);
if (!error) {
error = disable_nonboot_cpus();
if (!error)
error = swsusp_resume();
enable_nonboot_cpus();
}
platform_restore_cleanup(platform_mode);
device_resume();
Finish:
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) {
kernel_shutdown_prepare(SYSTEM_SUSPEND_DISK);
/*
* 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->prepare();
sysdev_shutdown();
if (!error)
error = hibernation_ops->enter();
} else {
error = -ENOSYS;
}
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_SHUTDOWN:
kernel_power_off();
break;
case HIBERNATION_REBOOT:
kernel_restart(NULL);
break;
case HIBERNATION_PLATFORM:
hibernation_platform_enter();
}
kernel_halt();
/*
* Valid image is on the disk, if we continue we risk serious data
* corruption after resume.
*/
printk(KERN_CRIT "Please power me down manually\n");
while(1);
}
static void unprepare_processes(void)
{
thaw_processes();
pm_restore_console();
}
static int prepare_processes(void)
{
int error = 0;
pm_prepare_console();
if (freeze_processes()) {
error = -EBUSY;
unprepare_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;
}
error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
if (error)
goto Exit;
/* Allocate memory management structures */
error = create_basic_memory_bitmaps();
if (error)
goto Exit;
error = prepare_processes();
if (error)
goto Finish;
if (hibernation_mode == HIBERNATION_TESTPROC) {
printk("swsusp debug: Waiting for 5 seconds.\n");
mdelay(5000);
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:
unprepare_processes();
Finish:
free_basic_memory_bitmaps();
Exit:
pm_notifier_call_chain(PM_POST_HIBERNATION);
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;
mutex_lock(&pm_mutex);
if (!swsusp_resume_device) {
if (!strlen(resume_file)) {
mutex_unlock(&pm_mutex);
return -ENOENT;
}
swsusp_resume_device = name_to_dev_t(resume_file);
pr_debug("swsusp: Resume From Partition %s\n", resume_file);
} else {
pr_debug("swsusp: Resume From Partition %d:%d\n",
MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
}
if (noresume) {
/**
* FIXME: If noresume is specified, we need to find the partition
* and reset it back to normal swap space.
*/
mutex_unlock(&pm_mutex);
return 0;
}
pr_debug("PM: Checking swsusp 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;
}
error = create_basic_memory_bitmaps();
if (error)
goto Finish;
pr_debug("PM: Preparing processes for restore.\n");
error = prepare_processes();
if (error) {
swsusp_close();
goto Done;
}
pr_debug("PM: Reading swsusp image.\n");
error = swsusp_read(&flags);
if (!error)
hibernation_restore(flags & SF_PLATFORM_MODE);
printk(KERN_ERR "PM: Restore failed, recovering.\n");
swsusp_free();
unprepare_processes();
Done:
free_basic_memory_bitmaps();
Finish:
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 kset *kset, 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 kset *kset, 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: suspend-to-disk 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 kset *kset, char *buf)
{
return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
MINOR(swsusp_resume_device));
}
static ssize_t resume_store(struct kset *kset, 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("Attempting manual resume\n");
noresume = 0;
software_resume();
ret = n;
out:
return ret;
}
power_attr(resume);
static ssize_t image_size_show(struct kset *kset, char *buf)
{
return sprintf(buf, "%lu\n", image_size);
}
static ssize_t image_size_store(struct kset *kset, 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_subsys.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);