diff options
| -rw-r--r-- | include/linux/kmod.h | 3 | ||||
| -rw-r--r-- | kernel/kmod.c | 65 | ||||
| -rw-r--r-- | kernel/power/disk.c | 11 | ||||
| -rw-r--r-- | kernel/power/main.c | 7 | ||||
| -rw-r--r-- | kernel/power/user.c | 10 |
5 files changed, 58 insertions, 38 deletions
diff --git a/include/linux/kmod.h b/include/linux/kmod.h index a1a9157..92213a9 100644 --- a/include/linux/kmod.h +++ b/include/linux/kmod.h @@ -99,4 +99,7 @@ struct file; extern int call_usermodehelper_pipe(char *path, char *argv[], char *envp[], struct file **filp); +extern int usermodehelper_disable(void); +extern void usermodehelper_enable(void); + #endif /* __LINUX_KMOD_H__ */ diff --git a/kernel/kmod.c b/kernel/kmod.c index 2456d1a..ab7dd08 100644 --- a/kernel/kmod.c +++ b/kernel/kmod.c @@ -265,7 +265,7 @@ static void __call_usermodehelper(struct work_struct *work) } } -#ifdef CONFIG_PM +#ifdef CONFIG_PM_SLEEP /* * If set, call_usermodehelper_exec() will exit immediately returning -EBUSY * (used for preventing user land processes from being created after the user @@ -288,39 +288,37 @@ static DECLARE_WAIT_QUEUE_HEAD(running_helpers_waitq); */ #define RUNNING_HELPERS_TIMEOUT (5 * HZ) -static int usermodehelper_pm_callback(struct notifier_block *nfb, - unsigned long action, - void *ignored) +/** + * usermodehelper_disable - prevent new helpers from being started + */ +int usermodehelper_disable(void) { long retval; - switch (action) { - case PM_HIBERNATION_PREPARE: - case PM_SUSPEND_PREPARE: - usermodehelper_disabled = 1; - smp_mb(); - /* - * From now on call_usermodehelper_exec() won't start any new - * helpers, so it is sufficient if running_helpers turns out to - * be zero at one point (it may be increased later, but that - * doesn't matter). - */ - retval = wait_event_timeout(running_helpers_waitq, + usermodehelper_disabled = 1; + smp_mb(); + /* + * From now on call_usermodehelper_exec() won't start any new + * helpers, so it is sufficient if running_helpers turns out to + * be zero at one point (it may be increased later, but that + * doesn't matter). + */ + retval = wait_event_timeout(running_helpers_waitq, atomic_read(&running_helpers) == 0, RUNNING_HELPERS_TIMEOUT); - if (retval) { - return NOTIFY_OK; - } else { - usermodehelper_disabled = 0; - return NOTIFY_BAD; - } - case PM_POST_HIBERNATION: - case PM_POST_SUSPEND: - usermodehelper_disabled = 0; - return NOTIFY_OK; - } + if (retval) + return 0; - return NOTIFY_DONE; + usermodehelper_disabled = 0; + return -EAGAIN; +} + +/** + * usermodehelper_enable - allow new helpers to be started again + */ +void usermodehelper_enable(void) +{ + usermodehelper_disabled = 0; } static void helper_lock(void) @@ -334,18 +332,12 @@ static void helper_unlock(void) if (atomic_dec_and_test(&running_helpers)) wake_up(&running_helpers_waitq); } - -static void register_pm_notifier_callback(void) -{ - pm_notifier(usermodehelper_pm_callback, 0); -} -#else /* CONFIG_PM */ +#else /* CONFIG_PM_SLEEP */ #define usermodehelper_disabled 0 static inline void helper_lock(void) {} static inline void helper_unlock(void) {} -static inline void register_pm_notifier_callback(void) {} -#endif /* CONFIG_PM */ +#endif /* CONFIG_PM_SLEEP */ /** * call_usermodehelper_setup - prepare to call a usermode helper @@ -515,5 +507,4 @@ void __init usermodehelper_init(void) { khelper_wq = create_singlethread_workqueue("khelper"); BUG_ON(!khelper_wq); - register_pm_notifier_callback(); } diff --git a/kernel/power/disk.c b/kernel/power/disk.c index bbd85c6..331f983 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -14,6 +14,7 @@ #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> @@ -520,6 +521,10 @@ int hibernate(void) if (error) goto Exit; + error = usermodehelper_disable(); + if (error) + goto Exit; + /* Allocate memory management structures */ error = create_basic_memory_bitmaps(); if (error) @@ -558,6 +563,7 @@ int hibernate(void) thaw_processes(); Finish: free_basic_memory_bitmaps(); + usermodehelper_enable(); Exit: pm_notifier_call_chain(PM_POST_HIBERNATION); pm_restore_console(); @@ -634,6 +640,10 @@ static int software_resume(void) if (error) goto Finish; + error = usermodehelper_disable(); + if (error) + goto Finish; + error = create_basic_memory_bitmaps(); if (error) goto Finish; @@ -656,6 +666,7 @@ static int software_resume(void) thaw_processes(); Done: free_basic_memory_bitmaps(); + usermodehelper_enable(); Finish: pm_notifier_call_chain(PM_POST_RESTORE); pm_restore_console(); diff --git a/kernel/power/main.c b/kernel/power/main.c index 540b16b..19122cf 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -14,6 +14,7 @@ #include <linux/string.h> #include <linux/delay.h> #include <linux/errno.h> +#include <linux/kmod.h> #include <linux/init.h> #include <linux/console.h> #include <linux/cpu.h> @@ -237,6 +238,10 @@ static int suspend_prepare(void) if (error) goto Finish; + error = usermodehelper_disable(); + if (error) + goto Finish; + if (suspend_freeze_processes()) { error = -EAGAIN; goto Thaw; @@ -256,6 +261,7 @@ static int suspend_prepare(void) Thaw: suspend_thaw_processes(); + usermodehelper_enable(); Finish: pm_notifier_call_chain(PM_POST_SUSPEND); pm_restore_console(); @@ -376,6 +382,7 @@ int suspend_devices_and_enter(suspend_state_t state) static void suspend_finish(void) { suspend_thaw_processes(); + usermodehelper_enable(); pm_notifier_call_chain(PM_POST_SUSPEND); pm_restore_console(); } diff --git a/kernel/power/user.c b/kernel/power/user.c index a6332a3..005b93d 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -212,13 +212,20 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, case SNAPSHOT_FREEZE: if (data->frozen) break; + printk("Syncing filesystems ... "); sys_sync(); printk("done.\n"); - error = freeze_processes(); + error = usermodehelper_disable(); if (error) + break; + + error = freeze_processes(); + if (error) { thaw_processes(); + usermodehelper_enable(); + } if (!error) data->frozen = 1; break; @@ -227,6 +234,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, if (!data->frozen || data->ready) break; thaw_processes(); + usermodehelper_enable(); data->frozen = 0; break; |