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Commit f0d99f82 authored by Patrick Mochel's avatar Patrick Mochel
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[power] Separate suspend-to-disk from other suspend sequences. 

- Put in kernel/power/disk.c
- Make compilation depend on CONFIG_SOFTWARE_SUSPEND (should probably be 
  renamed to CONFIG_PM_STD or some such).
parent 3f504f86
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Showing with 401 additions and 371 deletions
kernel/power/Makefile
View file @ f0d99f82
obj-y := main.o process.o console.o pm.o
obj-$(CONFIG_SOFTWARE_SUSPEND) += swsusp.o
obj-$(CONFIG_SOFTWARE_SUSPEND) += disk.o swsusp.o
obj-$(CONFIG_MAGIC_SYSRQ) += poweroff.o
kernel/power/disk.c 0 → 100644
View file @ f0d99f82
/*
* kernel/power/disk.c - Suspend-to-disk support.
*
* Copyright (c) 2003 Patrick Mochel
* Copyright (c) 2003 Open Source Development Lab
*
* This file is release under the GPLv2
*
*/
#define DEBUG
#include <linux/suspend.h>
#include <linux/reboot.h>
#include <linux/string.h>
#include <linux/delay.h>
#include <linux/fs.h>
#include "power.h"
extern u32 pm_disk_mode;
extern struct pm_ops * pm_ops;
extern int swsusp_save(void);
extern int swsusp_write(void);
extern int swsusp_read(void);
extern int swsusp_restore(void);
extern int swsusp_free(void);
extern long sys_sync(void);
/**
* power_down - Shut machine down for hibernate.
* @mode: Suspend-to-disk mode
*
* Use the platform driver, if configured so, and return gracefully if it
* fails.
* Otherwise, try to power off and reboot. If they fail, halt the machine,
* there ain't no turning back.
*/
static int power_down(u32 mode)
{
unsigned long flags;
int error = 0;
local_irq_save(flags);
device_power_down(PM_SUSPEND_DISK);
switch(mode) {
case PM_DISK_PLATFORM:
error = pm_ops->enter(PM_SUSPEND_DISK);
break;
case PM_DISK_SHUTDOWN:
printk("Powering off system\n");
machine_power_off();
break;
case PM_DISK_REBOOT:
machine_restart(NULL);
break;
}
machine_halt();
device_power_up();
local_irq_restore(flags);
return 0;
}
static int in_suspend __nosavedata = 0;
/**
* free_some_memory - Try to free as much memory as possible
*
* ... but do not OOM-kill anyone
*
* Notice: all userland should be stopped at this point, or
* livelock is possible.
*/
static void free_some_memory(void)
{
printk("Freeing memory: ");
while (shrink_all_memory(10000))
printk(".");
printk("|\n");
blk_run_queues();
}
static inline void platform_finish(void)
{
if (pm_disk_mode == PM_DISK_PLATFORM) {
if (pm_ops && pm_ops->finish)
pm_ops->finish(PM_SUSPEND_DISK);
}
}
static void finish(void)
{
device_resume();
platform_finish();
thaw_processes();
pm_restore_console();
}
static int prepare(void)
{
int error;
pm_prepare_console();
sys_sync();
if (freeze_processes()) {
error = -EBUSY;
goto Thaw;
}
if (pm_disk_mode == PM_DISK_PLATFORM) {
if (pm_ops && pm_ops->prepare) {
if ((error = pm_ops->prepare(PM_SUSPEND_DISK)))
goto Thaw;
}
}
/* Free memory before shutting down devices. */
free_some_memory();
if ((error = device_suspend(PM_SUSPEND_DISK)))
goto Finish;
return 0;
Finish:
platform_finish();
Thaw:
thaw_processes();
pm_restore_console();
return error;
}
/**
* pm_suspend_disk - The granpappy of power management.
*
* If we're going through the firmware, then get it over with quickly.
*
* If not, then call swsusp to do it's thing, then figure out how
* to power down the system.
*/
int pm_suspend_disk(void)
{
int error;
if ((error = prepare()))
return error;
pr_debug("PM: Attempting to suspend to disk.\n");
if (pm_disk_mode == PM_DISK_FIRMWARE)
return pm_ops->enter(PM_SUSPEND_DISK);
pr_debug("PM: snapshotting memory.\n");
in_suspend = 1;
local_irq_disable();
if ((error = swsusp_save()))
goto Done;
pr_debug("PM: writing image.\n");
/*
* FIXME: Leftover from swsusp. Are they necessary?
*/
mb();
barrier();
error = swsusp_write();
if (!error && in_suspend) {
error = power_down(pm_disk_mode);
pr_debug("PM: Power down failed.\n");
} else
pr_debug("PM: Image restored successfully.\n");
swsusp_free();
Done:
local_irq_enable();
finish();
return error;
}
/**
* pm_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 pm_suspend_disk() ) if everything goes well.
* Otherwise, we fail gracefully and return to the normally
* scheduled program.
*
*/
static int pm_resume(void)
{
int error;
pr_debug("PM: Reading swsusp image.\n");
if ((error = swsusp_read()))
goto Done;
pr_debug("PM: Preparing system for restore.\n");
if ((error = prepare()))
goto Free;
barrier();
mb();
local_irq_disable();
/* FIXME: The following (comment and mdelay()) are from swsusp.
* Are they really necessary?
*
* We do not want some readahead with DMA to corrupt our memory, right?
* Do it with disabled interrupts for best effect. That way, if some
* driver scheduled DMA, we have good chance for DMA to finish ;-).
*/
pr_debug("PM: Waiting for DMAs to settle down.\n");
mdelay(1000);
pr_debug("PM: Restoring saved image.\n");
swsusp_restore();
local_irq_enable();
pr_debug("PM: Restore failed, recovering.n");
finish();
Free:
swsusp_free();
Done:
pr_debug("PM: Resume from disk failed.\n");
return 0;
}
late_initcall(pm_resume);
static char * pm_disk_modes[] = {
[PM_DISK_FIRMWARE] = "firmware",
[PM_DISK_PLATFORM] = "platform",
[PM_DISK_SHUTDOWN] = "shutdown",
[PM_DISK_REBOOT] = "reboot",
};
/**
* disk - Control suspend-to-disk mode
*
* Suspend-to-disk can be handled in several ways. The greatest
* distinction is who writes memory to disk - the firmware or the OS.
* If the firmware does it, we assume that it also handles suspending
* the system.
* If the OS does it, then we have three options for putting the system
* to sleep - using the platform driver (e.g. ACPI or other PM registers),
* powering off the system or rebooting the system (for testing).
*
* The system will support either 'firmware' or 'platform', and that is
* known a priori (and encoded in pm_ops). But, the user may choose
* 'shutdown' or 'reboot' as alternatives.
*
* show() will display what the mode is currently set to.
* store() will accept one of
*
* 'firmware'
* 'platform'
* 'shutdown'
* 'reboot'
*
* It will only change to 'firmware' or 'platform' if the system
* supports it (as determined from pm_ops->pm_disk_mode).
*/
static ssize_t disk_show(struct subsystem * subsys, char * buf)
{
return sprintf(buf,"%s\n",pm_disk_modes[pm_disk_mode]);
}
static ssize_t disk_store(struct subsystem * s, const char * buf, size_t n)
{
int error = 0;
int i;
u32 mode = 0;
down(&pm_sem);
for (i = PM_DISK_FIRMWARE; i < PM_DISK_MAX; i++) {
if (!strcmp(buf,pm_disk_modes[i])) {
mode = i;
break;
}
}
if (mode) {
if (mode == PM_DISK_SHUTDOWN || mode == PM_DISK_REBOOT)
pm_disk_mode = mode;
else {
if (pm_ops && pm_ops->enter &&
(mode == pm_ops->pm_disk_mode))
pm_disk_mode = mode;
else
error = -EINVAL;
}
} else
error = -EINVAL;
pr_debug("PM: suspend-to-disk mode set to '%s'\n",
pm_disk_modes[mode]);
up(&pm_sem);
return error ? error : n;
}
power_attr(disk);
static struct attribute * g[] = {
&disk_attr.attr,
NULL,
};
static struct attribute_group attr_group = {
.attrs = g,
};
static int __init pm_disk_init(void)
{
return sysfs_create_group(&power_subsys.kset.kobj,&attr_group);
}
core_initcall(pm_disk_init);
kernel/power/main.c
View file @ f0d99f82
......@@ -12,31 +12,19 @@
#include <linux/suspend.h>
#include <linux/kobject.h>
#include <linux/reboot.h>
#include <linux/string.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/pm.h>
#include <linux/fs.h>
#include "power.h"
static DECLARE_MUTEX(pm_sem);
static struct pm_ops * pm_ops = NULL;
static u32 pm_disk_mode = PM_DISK_SHUTDOWN;
#ifdef CONFIG_SOFTWARE_SUSPEND
static int have_swsusp = 1;
#else
static int have_swsusp = 0;
#endif
extern long sys_sync(void);
DECLARE_MUTEX(pm_sem);
struct pm_ops * pm_ops = NULL;
u32 pm_disk_mode = PM_DISK_SHUTDOWN;
/**
* pm_set_ops - Set the global power method table.
......@@ -53,179 +41,6 @@ void pm_set_ops(struct pm_ops * ops)
}
/**
* pm_suspend_standby - Enter 'standby' state.
*
* 'standby' is also known as 'Power-On Suspend'. Here, we power down
* devices, disable interrupts, and enter the state.
*/
static int pm_suspend_standby(void)
{
int error = 0;
unsigned long flags;
if (!pm_ops || !pm_ops->enter)
return -EPERM;
local_irq_save(flags);
if ((error = device_power_down(PM_SUSPEND_STANDBY)))
goto Done;
error = pm_ops->enter(PM_SUSPEND_STANDBY);
local_irq_restore(flags);
device_power_up();
Done:
return error;
}
/**
* pm_suspend_mem - Enter suspend-to-RAM state.
*
* Identical to pm_suspend_standby() - we power down devices, disable
* interrupts, and enter the low-power state.
*/
static int pm_suspend_mem(void)
{
int error = 0;
unsigned long flags;
if (!pm_ops || !pm_ops->enter)
return -EPERM;
local_irq_save(flags);
if ((error = device_power_down(PM_SUSPEND_STANDBY)))
goto Done;
error = pm_ops->enter(PM_SUSPEND_STANDBY);
local_irq_restore(flags);
device_power_up();
Done:
return error;
}
/**
* power_down - Shut machine down for hibernate.
* @mode: Suspend-to-disk mode
*
* Use the platform driver, if configured so, and return gracefully if it
* fails.
* Otherwise, try to power off and reboot. If they fail, halt the machine,
* there ain't no turning back.
*/
static int power_down(u32 mode)
{
unsigned long flags;
int error = 0;
local_irq_save(flags);
device_power_down(PM_SUSPEND_DISK);
switch(mode) {
case PM_DISK_PLATFORM:
error = pm_ops->enter(PM_SUSPEND_DISK);
break;
case PM_DISK_SHUTDOWN:
printk("Powering off system\n");
machine_power_off();
break;
case PM_DISK_REBOOT:
machine_restart(NULL);
break;
}
machine_halt();
device_power_up();
local_irq_restore(flags);
return 0;
}
static int in_suspend __nosavedata = 0;
/**
* free_some_memory - Try to free as much memory as possible
*
* ... but do not OOM-kill anyone
*
* Notice: all userland should be stopped at this point, or
* livelock is possible.
*/
static void free_some_memory(void)
{
printk("Freeing memory: ");
while (shrink_all_memory(10000))
printk(".");
printk("|\n");
blk_run_queues();
}
/**
* pm_suspend_disk - The granpappy of power management.
*
* If we're going through the firmware, then get it over with quickly.
*
* If not, then call swsusp to do it's thing, then figure out how
* to power down the system.
*/
static int pm_suspend_disk(void)
{
int error;
pr_debug("PM: Attempting to suspend to disk.\n");
if (pm_disk_mode == PM_DISK_FIRMWARE)
return pm_ops->enter(PM_SUSPEND_DISK);
if (!have_swsusp)
return -EPERM;
pr_debug("PM: snapshotting memory.\n");
in_suspend = 1;
local_irq_disable();
if ((error = swsusp_save()))
goto Done;
if (in_suspend) {
pr_debug("PM: writing image.\n");
/*
* FIXME: Leftover from swsusp. Are they necessary?
*/
mb();
barrier();
error = swsusp_write();
if (!error)
error = power_down(pm_disk_mode);
pr_debug("PM: Power down failed.\n");
} else
pr_debug("PM: Image restored successfully.\n");
swsusp_free();
Done:
local_irq_enable();
return error;
}
#define decl_state(_name) \
{ .name = __stringify(_name), .fn = pm_suspend_##_name }
struct pm_state {
char * name;
int (*fn)(void);
} pm_states[] = {
[PM_SUSPEND_STANDBY] = decl_state(standby),
[PM_SUSPEND_MEM] = decl_state(mem),
[PM_SUSPEND_DISK] = decl_state(disk),
{ NULL },
};
/**
* suspend_prepare - Do prep work before entering low-power state.
* @state: State we're entering.
......@@ -239,23 +54,21 @@ static int suspend_prepare(u32 state)
{
int error = 0;
if (!pm_ops || !pm_ops->enter)
return -EPERM;
pm_prepare_console();
sys_sync();
if (freeze_processes()) {
error = -EAGAIN;
goto Thaw;
}
if (pm_ops && pm_ops->prepare) {
if (pm_ops->prepare) {
if ((error = pm_ops->prepare(state)))
goto Thaw;
}
/* Free memory before shutting down devices. */
if (state == PM_SUSPEND_DISK)
free_some_memory();
if ((error = device_suspend(state)))
goto Finish;
......@@ -264,7 +77,7 @@ static int suspend_prepare(u32 state)
pm_restore_console();
return error;
Finish:
if (pm_ops && pm_ops->finish)
if (pm_ops->finish)
pm_ops->finish(state);
Thaw:
thaw_processes();
......@@ -272,6 +85,22 @@ static int suspend_prepare(u32 state)
}
static int suspend_enter(u32 state)
{
int error = 0;
unsigned long flags;
local_irq_save(flags);
if ((error = device_power_down(state)))
goto Done;
error = pm_ops->enter(state);
local_irq_restore(flags);
device_power_up();
Done:
return error;
}
/**
* suspend_finish - Do final work before exiting suspend sequence.
* @state: State we're coming out of.
......@@ -290,6 +119,16 @@ static void suspend_finish(u32 state)
}
char * pm_states[] = {
[PM_SUSPEND_STANDBY] = "standby",
[PM_SUSPEND_MEM] = "mem",
[PM_SUSPEND_DISK] = "disk",
NULL,
};
/**
* enter_state - Do common work of entering low-power state.
* @state: pm_state structure for state we're entering.
......@@ -304,7 +143,6 @@ static void suspend_finish(u32 state)
static int enter_state(u32 state)
{
int error;
struct pm_state * s = &pm_states[state];
if (down_trylock(&pm_sem))
return -EBUSY;
......@@ -315,12 +153,17 @@ static int enter_state(u32 state)
goto Unlock;
}
if (state == PM_SUSPEND_DISK) {
error = pm_suspend_disk();
goto Unlock;
}
pr_debug("PM: Preparing system for suspend\n");
if ((error = suspend_prepare(state)))
goto Unlock;
pr_debug("PM: Entering state.\n");
error = s->fn();
error = suspend_enter(state);
pr_debug("PM: Finishing up.\n");
suspend_finish(state);
......@@ -346,152 +189,10 @@ int pm_suspend(u32 state)
}
/**
* pm_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 pm_suspend_disk() ) if everything goes well.
* Otherwise, we fail gracefully and return to the normally
* scheduled program.
*
*/
static int pm_resume(void)
{
int error;
if (!have_swsusp)
return 0;
pr_debug("PM: Reading swsusp image.\n");
if ((error = swsusp_read()))
goto Done;
pr_debug("PM: Preparing system for restore.\n");
if ((error = suspend_prepare(PM_SUSPEND_DISK)))
goto Free;
barrier();
mb();
local_irq_disable();
/* FIXME: The following (comment and mdelay()) are from swsusp.
* Are they really necessary?
*
* We do not want some readahead with DMA to corrupt our memory, right?
* Do it with disabled interrupts for best effect. That way, if some
* driver scheduled DMA, we have good chance for DMA to finish ;-).
*/
pr_debug("PM: Waiting for DMAs to settle down.\n");
mdelay(1000);
pr_debug("PM: Restoring saved image.\n");
swsusp_restore();
local_irq_enable();
pr_debug("PM: Restore failed, recovering.n");
suspend_finish(PM_SUSPEND_DISK);
Free:
swsusp_free();
Done:
pr_debug("PM: Resume from disk failed.\n");
return 0;
}
late_initcall(pm_resume);
decl_subsys(power,NULL,NULL);
#define power_attr(_name) \
static struct subsys_attribute _name##_attr = { \
.attr = { \
.name = __stringify(_name), \
.mode = 0644, \
}, \
.show = _name##_show, \
.store = _name##_store, \
}
static char * pm_disk_modes[] = {
[PM_DISK_FIRMWARE] = "firmware",
[PM_DISK_PLATFORM] = "platform",
[PM_DISK_SHUTDOWN] = "shutdown",
[PM_DISK_REBOOT] = "reboot",
};
/**
* disk - Control suspend-to-disk mode
*
* Suspend-to-disk can be handled in several ways. The greatest
* distinction is who writes memory to disk - the firmware or the OS.
* If the firmware does it, we assume that it also handles suspending
* the system.
* If the OS does it, then we have three options for putting the system
* to sleep - using the platform driver (e.g. ACPI or other PM registers),
* powering off the system or rebooting the system (for testing).
*
* The system will support either 'firmware' or 'platform', and that is
* known a priori (and encoded in pm_ops). But, the user may choose
* 'shutdown' or 'reboot' as alternatives.
*
* show() will display what the mode is currently set to.
* store() will accept one of
*
* 'firmware'
* 'platform'
* 'shutdown'
* 'reboot'
*
* It will only change to 'firmware' or 'platform' if the system
* supports it (as determined from pm_ops->pm_disk_mode).
*/
static ssize_t disk_show(struct subsystem * subsys, char * buf)
{
return sprintf(buf,"%s\n",pm_disk_modes[pm_disk_mode]);
}
static ssize_t disk_store(struct subsystem * s, const char * buf, size_t n)
{
int error = 0;
int i;
u32 mode = 0;
down(&pm_sem);
for (i = PM_DISK_FIRMWARE; i < PM_DISK_MAX; i++) {
if (!strcmp(buf,pm_disk_modes[i])) {
mode = i;
break;
}
}
if (mode) {
if (mode == PM_DISK_SHUTDOWN || mode == PM_DISK_REBOOT)
pm_disk_mode = mode;
else {
if (pm_ops && pm_ops->enter &&
(mode == pm_ops->pm_disk_mode))
pm_disk_mode = mode;
else
error = -EINVAL;
}
} else
error = -EINVAL;
pr_debug("PM: suspend-to-disk mode set to '%s'\n",
pm_disk_modes[mode]);
up(&pm_sem);
return error ? error : n;
}
power_attr(disk);
/**
* state - control system power state.
*
......@@ -509,8 +210,8 @@ static ssize_t state_show(struct subsystem * subsys, char * buf)
char * s = buf;
for (i = 0; i < PM_SUSPEND_MAX; i++) {
if (pm_states[i].name)
s += sprintf(s,"%s ",pm_states[i].name);
if (pm_states[i])
s += sprintf(s,"%s ",pm_states[i]);
}
s += sprintf(s,"\n");
return (s - buf);
......@@ -519,14 +220,14 @@ static ssize_t state_show(struct subsystem * subsys, char * buf)
static ssize_t state_store(struct subsystem * subsys, const char * buf, size_t n)
{
u32 state = PM_SUSPEND_STANDBY;
struct pm_state * s;
char ** s;
int error;
for (s = &pm_states[state]; s->name; s++, state++) {
if (!strcmp(buf,s->name))
for (s = &pm_states[state]; *s; s++, state++) {
if (!strcmp(buf,*s))
break;
}
if (s->name)
if (*s)
error = enter_state(state);
else
error = -EINVAL;
......@@ -537,7 +238,6 @@ power_attr(state);
static struct attribute * g[] = {
&state_attr.attr,
&disk_attr.attr,
NULL,
};
......@@ -546,7 +246,7 @@ static struct attribute_group attr_group = {
};
static int pm_init(void)
static int __init pm_init(void)
{
int error = subsystem_register(&power_subsys);
if (!error)
......
kernel/power/power.h
View file @ f0d99f82
......@@ -10,34 +10,27 @@
#ifdef CONFIG_SOFTWARE_SUSPEND
extern int swsusp_save(void);
extern int swsusp_write(void);
extern int swsusp_read(void);
extern int swsusp_restore(void);
extern int swsusp_free(void);
extern int pm_suspend_disk(void);
#else
static inline int swsusp_save(void)
{
return 0;
}
static inline int swsusp_write(void)
static inline int pm_suspend_disk(void)
{
return 0;
}
static inline int swsusp_read(void)
{
return 0;
}
static inline int swsusp_restore(void)
{
return 0;
}
static inline int swsusp_free(void)
{
return 0;
return -EPERM;
}
#endif
extern struct semaphore pm_sem;
#define power_attr(_name) \
static struct subsys_attribute _name##_attr = { \
.attr = { \
.name = __stringify(_name), \
.mode = 0644, \
}, \
.show = _name##_show, \
.store = _name##_store, \
}
extern struct subsystem power_subsys;
extern int freeze_processes(void);
extern void thaw_processes(void);
......
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