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Diffstat (limited to 'kernel/power')
-rw-r--r--kernel/power/disk.c50
-rw-r--r--kernel/power/main.c16
-rw-r--r--kernel/power/process.c97
-rw-r--r--kernel/power/user.c71
4 files changed, 135 insertions, 99 deletions
diff --git a/kernel/power/disk.c b/kernel/power/disk.c
index 14a656cdc65..f011e0870b5 100644
--- a/kernel/power/disk.c
+++ b/kernel/power/disk.c
@@ -180,6 +180,17 @@ static void platform_restore_cleanup(int platform_mode)
}
/**
+ * 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.
@@ -193,6 +204,7 @@ static int create_image(int platform_mode)
if (error)
return error;
+ device_pm_lock();
local_irq_disable();
/* At this point, device_suspend() has been called, but *not*
* device_power_down(). We *must* call device_power_down() now.
@@ -224,9 +236,11 @@ static int create_image(int platform_mode)
/* NOTE: device_power_up() is just a resume() for devices
* that suspended with irqs off ... no overall powerup.
*/
- device_power_up();
+ device_power_up(in_suspend ?
+ (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
Enable_irqs:
local_irq_enable();
+ device_pm_unlock();
return error;
}
@@ -255,10 +269,10 @@ int hibernation_snapshot(int platform_mode)
suspend_console();
error = device_suspend(PMSG_FREEZE);
if (error)
- goto Resume_console;
+ goto Recover_platform;
if (hibernation_test(TEST_DEVICES))
- goto Resume_devices;
+ goto Recover_platform;
error = platform_pre_snapshot(platform_mode);
if (error || hibernation_test(TEST_PLATFORM))
@@ -280,12 +294,16 @@ int hibernation_snapshot(int platform_mode)
Finish:
platform_finish(platform_mode);
Resume_devices:
- device_resume();
- Resume_console:
+ device_resume(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;
}
/**
@@ -300,8 +318,9 @@ static int resume_target_kernel(void)
{
int error;
+ device_pm_lock();
local_irq_disable();
- error = device_power_down(PMSG_PRETHAW);
+ error = device_power_down(PMSG_QUIESCE);
if (error) {
printk(KERN_ERR "PM: Some devices failed to power down, "
"aborting resume\n");
@@ -329,9 +348,10 @@ static int resume_target_kernel(void)
swsusp_free();
restore_processor_state();
touch_softlockup_watchdog();
- device_power_up();
+ device_power_up(PMSG_RECOVER);
Enable_irqs:
local_irq_enable();
+ device_pm_unlock();
return error;
}
@@ -350,7 +370,7 @@ int hibernation_restore(int platform_mode)
pm_prepare_console();
suspend_console();
- error = device_suspend(PMSG_PRETHAW);
+ error = device_suspend(PMSG_QUIESCE);
if (error)
goto Finish;
@@ -362,7 +382,7 @@ int hibernation_restore(int platform_mode)
enable_nonboot_cpus();
}
platform_restore_cleanup(platform_mode);
- device_resume();
+ device_resume(PMSG_RECOVER);
Finish:
resume_console();
pm_restore_console();
@@ -392,8 +412,11 @@ int hibernation_platform_enter(void)
suspend_console();
error = device_suspend(PMSG_HIBERNATE);
- if (error)
- goto Resume_console;
+ if (error) {
+ if (hibernation_ops->recover)
+ hibernation_ops->recover();
+ goto Resume_devices;
+ }
error = hibernation_ops->prepare();
if (error)
@@ -403,6 +426,7 @@ int hibernation_platform_enter(void)
if (error)
goto Finish;
+ device_pm_lock();
local_irq_disable();
error = device_power_down(PMSG_HIBERNATE);
if (!error) {
@@ -411,6 +435,7 @@ int hibernation_platform_enter(void)
while (1);
}
local_irq_enable();
+ device_pm_unlock();
/*
* We don't need to reenable the nonboot CPUs or resume consoles, since
@@ -419,8 +444,7 @@ int hibernation_platform_enter(void)
Finish:
hibernation_ops->finish();
Resume_devices:
- device_resume();
- Resume_console:
+ device_resume(PMSG_RESTORE);
resume_console();
Close:
hibernation_ops->end();
diff --git a/kernel/power/main.c b/kernel/power/main.c
index 6a6d5eb3524..3398f4651aa 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -228,6 +228,7 @@ static int suspend_enter(suspend_state_t state)
{
int error = 0;
+ device_pm_lock();
arch_suspend_disable_irqs();
BUG_ON(!irqs_disabled());
@@ -239,10 +240,11 @@ static int suspend_enter(suspend_state_t state)
if (!suspend_test(TEST_CORE))
error = suspend_ops->enter(state);
- device_power_up();
+ device_power_up(PMSG_RESUME);
Done:
arch_suspend_enable_irqs();
BUG_ON(irqs_disabled());
+ device_pm_unlock();
return error;
}
@@ -267,11 +269,11 @@ int suspend_devices_and_enter(suspend_state_t state)
error = device_suspend(PMSG_SUSPEND);
if (error) {
printk(KERN_ERR "PM: Some devices failed to suspend\n");
- goto Resume_console;
+ goto Recover_platform;
}
if (suspend_test(TEST_DEVICES))
- goto Resume_devices;
+ goto Recover_platform;
if (suspend_ops->prepare) {
error = suspend_ops->prepare();
@@ -291,13 +293,17 @@ int suspend_devices_and_enter(suspend_state_t state)
if (suspend_ops->finish)
suspend_ops->finish();
Resume_devices:
- device_resume();
- Resume_console:
+ device_resume(PMSG_RESUME);
resume_console();
Close:
if (suspend_ops->end)
suspend_ops->end();
return error;
+
+ Recover_platform:
+ if (suspend_ops->recover)
+ suspend_ops->recover();
+ goto Resume_devices;
}
/**
diff --git a/kernel/power/process.c b/kernel/power/process.c
index f1d0b345c9b..5fb87652f21 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -19,9 +19,6 @@
*/
#define TIMEOUT (20 * HZ)
-#define FREEZER_KERNEL_THREADS 0
-#define FREEZER_USER_SPACE 1
-
static inline int freezeable(struct task_struct * p)
{
if ((p == current) ||
@@ -84,63 +81,53 @@ static void fake_signal_wake_up(struct task_struct *p)
spin_unlock_irqrestore(&p->sighand->siglock, flags);
}
-static int has_mm(struct task_struct *p)
+static inline bool should_send_signal(struct task_struct *p)
{
- return (p->mm && !(p->flags & PF_BORROWED_MM));
+ return !(p->flags & PF_FREEZER_NOSIG);
}
/**
* freeze_task - send a freeze request to given task
* @p: task to send the request to
- * @with_mm_only: if set, the request will only be sent if the task has its
- * own mm
- * Return value: 0, if @with_mm_only is set and the task has no mm of its
- * own or the task is frozen, 1, otherwise
+ * @sig_only: if set, the request will only be sent if the task has the
+ * PF_FREEZER_NOSIG flag unset
+ * Return value: 'false', if @sig_only is set and the task has
+ * PF_FREEZER_NOSIG set or the task is frozen, 'true', otherwise
*
- * The freeze request is sent by seting the tasks's TIF_FREEZE flag and
+ * The freeze request is sent by setting the tasks's TIF_FREEZE flag and
* either sending a fake signal to it or waking it up, depending on whether
- * or not it has its own mm (ie. it is a user land task). If @with_mm_only
- * is set and the task has no mm of its own (ie. it is a kernel thread),
- * its TIF_FREEZE flag should not be set.
- *
- * The task_lock() is necessary to prevent races with exit_mm() or
- * use_mm()/unuse_mm() from occuring.
+ * or not it has PF_FREEZER_NOSIG set. If @sig_only is set and the task
+ * has PF_FREEZER_NOSIG set (ie. it is a typical kernel thread), its
+ * TIF_FREEZE flag will not be set.
*/
-static int freeze_task(struct task_struct *p, int with_mm_only)
+static bool freeze_task(struct task_struct *p, bool sig_only)
{
- int ret = 1;
+ /*
+ * We first check if the task is freezing and next if it has already
+ * been frozen to avoid the race with frozen_process() which first marks
+ * the task as frozen and next clears its TIF_FREEZE.
+ */
+ if (!freezing(p)) {
+ rmb();
+ if (frozen(p))
+ return false;
- task_lock(p);
- if (freezing(p)) {
- if (has_mm(p)) {
- if (!signal_pending(p))
- fake_signal_wake_up(p);
- } else {
- if (with_mm_only)
- ret = 0;
- else
- wake_up_state(p, TASK_INTERRUPTIBLE);
- }
+ if (!sig_only || should_send_signal(p))
+ set_freeze_flag(p);
+ else
+ return false;
+ }
+
+ if (should_send_signal(p)) {
+ if (!signal_pending(p))
+ fake_signal_wake_up(p);
+ } else if (sig_only) {
+ return false;
} else {
- rmb();
- if (frozen(p)) {
- ret = 0;
- } else {
- if (has_mm(p)) {
- set_freeze_flag(p);
- fake_signal_wake_up(p);
- } else {
- if (with_mm_only) {
- ret = 0;
- } else {
- set_freeze_flag(p);
- wake_up_state(p, TASK_INTERRUPTIBLE);
- }
- }
- }
+ wake_up_state(p, TASK_INTERRUPTIBLE);
}
- task_unlock(p);
- return ret;
+
+ return true;
}
static void cancel_freezing(struct task_struct *p)
@@ -156,7 +143,7 @@ static void cancel_freezing(struct task_struct *p)
}
}
-static int try_to_freeze_tasks(int freeze_user_space)
+static int try_to_freeze_tasks(bool sig_only)
{
struct task_struct *g, *p;
unsigned long end_time;
@@ -175,7 +162,7 @@ static int try_to_freeze_tasks(int freeze_user_space)
if (frozen(p) || !freezeable(p))
continue;
- if (!freeze_task(p, freeze_user_space))
+ if (!freeze_task(p, sig_only))
continue;
/*
@@ -235,13 +222,13 @@ int freeze_processes(void)
int error;
printk("Freezing user space processes ... ");
- error = try_to_freeze_tasks(FREEZER_USER_SPACE);
+ error = try_to_freeze_tasks(true);
if (error)
goto Exit;
printk("done.\n");
printk("Freezing remaining freezable tasks ... ");
- error = try_to_freeze_tasks(FREEZER_KERNEL_THREADS);
+ error = try_to_freeze_tasks(false);
if (error)
goto Exit;
printk("done.");
@@ -251,7 +238,7 @@ int freeze_processes(void)
return error;
}
-static void thaw_tasks(int thaw_user_space)
+static void thaw_tasks(bool nosig_only)
{
struct task_struct *g, *p;
@@ -260,7 +247,7 @@ static void thaw_tasks(int thaw_user_space)
if (!freezeable(p))
continue;
- if (!p->mm == thaw_user_space)
+ if (nosig_only && should_send_signal(p))
continue;
thaw_process(p);
@@ -271,8 +258,8 @@ static void thaw_tasks(int thaw_user_space)
void thaw_processes(void)
{
printk("Restarting tasks ... ");
- thaw_tasks(FREEZER_KERNEL_THREADS);
- thaw_tasks(FREEZER_USER_SPACE);
+ thaw_tasks(true);
+ thaw_tasks(false);
schedule();
printk("done.\n");
}
diff --git a/kernel/power/user.c b/kernel/power/user.c
index f5512cb3aa8..a6332a31326 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -23,6 +23,7 @@
#include <linux/console.h>
#include <linux/cpu.h>
#include <linux/freezer.h>
+#include <linux/smp_lock.h>
#include <asm/uaccess.h>
@@ -69,16 +70,22 @@ static int snapshot_open(struct inode *inode, struct file *filp)
struct snapshot_data *data;
int error;
- if (!atomic_add_unless(&snapshot_device_available, -1, 0))
- return -EBUSY;
+ mutex_lock(&pm_mutex);
+
+ if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+ error = -EBUSY;
+ goto Unlock;
+ }
if ((filp->f_flags & O_ACCMODE) == O_RDWR) {
atomic_inc(&snapshot_device_available);
- return -ENOSYS;
+ error = -ENOSYS;
+ goto Unlock;
}
if(create_basic_memory_bitmaps()) {
atomic_inc(&snapshot_device_available);
- return -ENOMEM;
+ error = -ENOMEM;
+ goto Unlock;
}
nonseekable_open(inode, filp);
data = &snapshot_state;
@@ -98,33 +105,36 @@ static int snapshot_open(struct inode *inode, struct file *filp)
if (error)
pm_notifier_call_chain(PM_POST_HIBERNATION);
}
- if (error) {
+ if (error)
atomic_inc(&snapshot_device_available);
- return error;
- }
data->frozen = 0;
data->ready = 0;
data->platform_support = 0;
- return 0;
+ Unlock:
+ mutex_unlock(&pm_mutex);
+
+ return error;
}
static int snapshot_release(struct inode *inode, struct file *filp)
{
struct snapshot_data *data;
+ mutex_lock(&pm_mutex);
+
swsusp_free();
free_basic_memory_bitmaps();
data = filp->private_data;
free_all_swap_pages(data->swap);
- if (data->frozen) {
- mutex_lock(&pm_mutex);
+ if (data->frozen)
thaw_processes();
- mutex_unlock(&pm_mutex);
- }
pm_notifier_call_chain(data->mode == O_WRONLY ?
PM_POST_HIBERNATION : PM_POST_RESTORE);
atomic_inc(&snapshot_device_available);
+
+ mutex_unlock(&pm_mutex);
+
return 0;
}
@@ -134,9 +144,13 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf,
struct snapshot_data *data;
ssize_t res;
+ mutex_lock(&pm_mutex);
+
data = filp->private_data;
- if (!data->ready)
- return -ENODATA;
+ if (!data->ready) {
+ res = -ENODATA;
+ goto Unlock;
+ }
res = snapshot_read_next(&data->handle, count);
if (res > 0) {
if (copy_to_user(buf, data_of(data->handle), res))
@@ -144,6 +158,10 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf,
else
*offp = data->handle.offset;
}
+
+ Unlock:
+ mutex_unlock(&pm_mutex);
+
return res;
}
@@ -153,6 +171,8 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf,
struct snapshot_data *data;
ssize_t res;
+ mutex_lock(&pm_mutex);
+
data = filp->private_data;
res = snapshot_write_next(&data->handle, count);
if (res > 0) {
@@ -161,11 +181,14 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf,
else
*offp = data->handle.offset;
}
+
+ mutex_unlock(&pm_mutex);
+
return res;
}
-static int snapshot_ioctl(struct inode *inode, struct file *filp,
- unsigned int cmd, unsigned long arg)
+static long snapshot_ioctl(struct file *filp, unsigned int cmd,
+ unsigned long arg)
{
int error = 0;
struct snapshot_data *data;
@@ -179,6 +202,9 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
+ if (!mutex_trylock(&pm_mutex))
+ return -EBUSY;
+
data = filp->private_data;
switch (cmd) {
@@ -186,7 +212,6 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
case SNAPSHOT_FREEZE:
if (data->frozen)
break;
- mutex_lock(&pm_mutex);
printk("Syncing filesystems ... ");
sys_sync();
printk("done.\n");
@@ -194,7 +219,6 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
error = freeze_processes();
if (error)
thaw_processes();
- mutex_unlock(&pm_mutex);
if (!error)
data->frozen = 1;
break;
@@ -202,9 +226,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
case SNAPSHOT_UNFREEZE:
if (!data->frozen || data->ready)
break;
- mutex_lock(&pm_mutex);
thaw_processes();
- mutex_unlock(&pm_mutex);
data->frozen = 0;
break;
@@ -307,16 +329,11 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
error = -EPERM;
break;
}
- if (!mutex_trylock(&pm_mutex)) {
- error = -EBUSY;
- break;
- }
/*
* Tasks are frozen and the notifiers have been called with
* PM_HIBERNATION_PREPARE
*/
error = suspend_devices_and_enter(PM_SUSPEND_MEM);
- mutex_unlock(&pm_mutex);
break;
case SNAPSHOT_PLATFORM_SUPPORT:
@@ -390,6 +407,8 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
}
+ mutex_unlock(&pm_mutex);
+
return error;
}
@@ -399,7 +418,7 @@ static const struct file_operations snapshot_fops = {
.read = snapshot_read,
.write = snapshot_write,
.llseek = no_llseek,
- .ioctl = snapshot_ioctl,
+ .unlocked_ioctl = snapshot_ioctl,
};
static struct miscdevice snapshot_device = {
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-25 12:06:25 +0000