diff options
Diffstat (limited to 'kernel/kmod.c')
-rw-r--r-- | kernel/kmod.c | 65 |
1 files changed, 28 insertions, 37 deletions
diff --git a/kernel/kmod.c b/kernel/kmod.c index 2456d1a0bef..ab7dd08472f 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(); } |