diff options
| -rw-r--r-- | drivers/base/firmware_class.c | 51 | ||||
| -rw-r--r-- | include/linux/kmod.h | 1 | ||||
| -rw-r--r-- | kernel/kmod.c | 58 |
3 files changed, 76 insertions, 34 deletions
diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c index 6029067..72c644b 100644 --- a/drivers/base/firmware_class.c +++ b/drivers/base/firmware_class.c @@ -81,6 +81,11 @@ enum { static int loading_timeout = 60; /* In seconds */ +static inline long firmware_loading_timeout(void) +{ + return loading_timeout > 0 ? loading_timeout * HZ : MAX_SCHEDULE_TIMEOUT; +} + /* fw_lock could be moved to 'struct firmware_priv' but since it is just * guarding for corner cases a global lock should be OK */ static DEFINE_MUTEX(fw_lock); @@ -541,31 +546,22 @@ static void _request_firmware_cleanup(const struct firmware **firmware_p) static int _request_firmware(const struct firmware *firmware, const char *name, struct device *device, - bool uevent, bool nowait) + bool uevent, bool nowait, long timeout) { struct firmware_priv *fw_priv; - int retval; - - retval = usermodehelper_read_trylock(); - if (WARN_ON(retval)) { - dev_err(device, "firmware: %s will not be loaded\n", name); - return retval; - } + int retval = 0; if (uevent) dev_dbg(device, "firmware: requesting %s\n", name); fw_priv = fw_create_instance(firmware, name, device, uevent, nowait); - if (IS_ERR(fw_priv)) { - retval = PTR_ERR(fw_priv); - goto out; - } + if (IS_ERR(fw_priv)) + return PTR_ERR(fw_priv); if (uevent) { - if (loading_timeout > 0) + if (timeout != MAX_SCHEDULE_TIMEOUT) mod_timer(&fw_priv->timeout, - round_jiffies_up(jiffies + - loading_timeout * HZ)); + round_jiffies_up(jiffies + timeout)); kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD); } @@ -582,9 +578,6 @@ static int _request_firmware(const struct firmware *firmware, mutex_unlock(&fw_lock); fw_destroy_instance(fw_priv); - -out: - usermodehelper_read_unlock(); return retval; } @@ -613,7 +606,14 @@ request_firmware(const struct firmware **firmware_p, const char *name, if (ret <= 0) return ret; - ret = _request_firmware(*firmware_p, name, device, true, false); + ret = usermodehelper_read_trylock(); + if (WARN_ON(ret)) { + dev_err(device, "firmware: %s will not be loaded\n", name); + } else { + ret = _request_firmware(*firmware_p, name, device, true, false, + firmware_loading_timeout()); + usermodehelper_read_unlock(); + } if (ret) _request_firmware_cleanup(firmware_p); @@ -648,6 +648,7 @@ static int request_firmware_work_func(void *arg) { struct firmware_work *fw_work = arg; const struct firmware *fw; + long timeout; int ret; if (!arg) { @@ -659,8 +660,16 @@ static int request_firmware_work_func(void *arg) if (ret <= 0) goto out; - ret = _request_firmware(fw, fw_work->name, fw_work->device, - fw_work->uevent, true); + timeout = usermodehelper_read_lock_wait(firmware_loading_timeout()); + if (timeout) { + ret = _request_firmware(fw, fw_work->name, fw_work->device, + fw_work->uevent, true, timeout); + usermodehelper_read_unlock(); + } else { + dev_dbg(fw_work->device, "firmware: %s loading timed out\n", + fw_work->name); + ret = -EAGAIN; + } if (ret) _request_firmware_cleanup(&fw); diff --git a/include/linux/kmod.h b/include/linux/kmod.h index 97d22c3..b087377 100644 --- a/include/linux/kmod.h +++ b/include/linux/kmod.h @@ -115,6 +115,7 @@ extern void usermodehelper_init(void); extern int usermodehelper_disable(void); extern void usermodehelper_enable(void); extern int usermodehelper_read_trylock(void); +extern long usermodehelper_read_lock_wait(long timeout); extern void usermodehelper_read_unlock(void); #endif /* __LINUX_KMOD_H__ */ diff --git a/kernel/kmod.c b/kernel/kmod.c index 4079ac1..da7fcca 100644 --- a/kernel/kmod.c +++ b/kernel/kmod.c @@ -334,6 +334,12 @@ static atomic_t running_helpers = ATOMIC_INIT(0); static DECLARE_WAIT_QUEUE_HEAD(running_helpers_waitq); /* + * Used by usermodehelper_read_lock_wait() to wait for usermodehelper_disabled + * to become 'false'. + */ +static DECLARE_WAIT_QUEUE_HEAD(usermodehelper_disabled_waitq); + +/* * Time to wait for running_helpers to become zero before the setting of * usermodehelper_disabled in usermodehelper_disable() fails */ @@ -352,6 +358,33 @@ int usermodehelper_read_trylock(void) } EXPORT_SYMBOL_GPL(usermodehelper_read_trylock); +long usermodehelper_read_lock_wait(long timeout) +{ + DEFINE_WAIT(wait); + + if (timeout < 0) + return -EINVAL; + + down_read(&umhelper_sem); + for (;;) { + prepare_to_wait(&usermodehelper_disabled_waitq, &wait, + TASK_UNINTERRUPTIBLE); + if (!usermodehelper_disabled) + break; + + up_read(&umhelper_sem); + + timeout = schedule_timeout(timeout); + if (!timeout) + break; + + down_read(&umhelper_sem); + } + finish_wait(&usermodehelper_disabled_waitq, &wait); + return timeout; +} +EXPORT_SYMBOL_GPL(usermodehelper_read_lock_wait); + void usermodehelper_read_unlock(void) { up_read(&umhelper_sem); @@ -359,6 +392,17 @@ void usermodehelper_read_unlock(void) EXPORT_SYMBOL_GPL(usermodehelper_read_unlock); /** + * usermodehelper_enable - allow new helpers to be started again + */ +void usermodehelper_enable(void) +{ + down_write(&umhelper_sem); + usermodehelper_disabled = 0; + wake_up(&usermodehelper_disabled_waitq); + up_write(&umhelper_sem); +} + +/** * usermodehelper_disable - prevent new helpers from being started */ int usermodehelper_disable(void) @@ -381,22 +425,10 @@ int usermodehelper_disable(void) if (retval) return 0; - down_write(&umhelper_sem); - usermodehelper_disabled = 0; - up_write(&umhelper_sem); + usermodehelper_enable(); return -EAGAIN; } -/** - * usermodehelper_enable - allow new helpers to be started again - */ -void usermodehelper_enable(void) -{ - down_write(&umhelper_sem); - usermodehelper_disabled = 0; - up_write(&umhelper_sem); -} - static void helper_lock(void) { atomic_inc(&running_helpers); |