diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/watchdog/watchdog_dev.c | 55 |
1 files changed, 54 insertions, 1 deletions
diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c index 4d295d229a07..672d169bf1da 100644 --- a/drivers/watchdog/watchdog_dev.c +++ b/drivers/watchdog/watchdog_dev.c @@ -65,6 +65,11 @@ static int watchdog_ping(struct watchdog_device *wddev) mutex_lock(&wddev->lock); + if (test_bit(WDOG_UNREGISTERED, &wddev->status)) { + err = -ENODEV; + goto out_ping; + } + if (!watchdog_active(wddev)) goto out_ping; @@ -93,6 +98,11 @@ static int watchdog_start(struct watchdog_device *wddev) mutex_lock(&wddev->lock); + if (test_bit(WDOG_UNREGISTERED, &wddev->status)) { + err = -ENODEV; + goto out_start; + } + if (watchdog_active(wddev)) goto out_start; @@ -121,6 +131,11 @@ static int watchdog_stop(struct watchdog_device *wddev) mutex_lock(&wddev->lock); + if (test_bit(WDOG_UNREGISTERED, &wddev->status)) { + err = -ENODEV; + goto out_stop; + } + if (!watchdog_active(wddev)) goto out_stop; @@ -158,8 +173,14 @@ static int watchdog_get_status(struct watchdog_device *wddev, mutex_lock(&wddev->lock); + if (test_bit(WDOG_UNREGISTERED, &wddev->status)) { + err = -ENODEV; + goto out_status; + } + *status = wddev->ops->status(wddev); +out_status: mutex_unlock(&wddev->lock); return err; } @@ -185,8 +206,14 @@ static int watchdog_set_timeout(struct watchdog_device *wddev, mutex_lock(&wddev->lock); + if (test_bit(WDOG_UNREGISTERED, &wddev->status)) { + err = -ENODEV; + goto out_timeout; + } + err = wddev->ops->set_timeout(wddev, timeout); +out_timeout: mutex_unlock(&wddev->lock); return err; } @@ -210,8 +237,14 @@ static int watchdog_get_timeleft(struct watchdog_device *wddev, mutex_lock(&wddev->lock); + if (test_bit(WDOG_UNREGISTERED, &wddev->status)) { + err = -ENODEV; + goto out_timeleft; + } + *timeleft = wddev->ops->get_timeleft(wddev); +out_timeleft: mutex_unlock(&wddev->lock); return err; } @@ -233,8 +266,14 @@ static int watchdog_ioctl_op(struct watchdog_device *wddev, unsigned int cmd, mutex_lock(&wddev->lock); + if (test_bit(WDOG_UNREGISTERED, &wddev->status)) { + err = -ENODEV; + goto out_ioctl; + } + err = wddev->ops->ioctl(wddev, cmd, arg); +out_ioctl: mutex_unlock(&wddev->lock); return err; } @@ -398,6 +437,9 @@ static int watchdog_open(struct inode *inode, struct file *file) file->private_data = wdd; + if (wdd->ops->ref) + wdd->ops->ref(wdd); + /* dev/watchdog is a virtual (and thus non-seekable) filesystem */ return nonseekable_open(inode, file); @@ -434,7 +476,10 @@ static int watchdog_release(struct inode *inode, struct file *file) /* If the watchdog was not stopped, send a keepalive ping */ if (err < 0) { - dev_crit(wdd->dev, "watchdog did not stop!\n"); + mutex_lock(&wdd->lock); + if (!test_bit(WDOG_UNREGISTERED, &wdd->status)) + dev_crit(wdd->dev, "watchdog did not stop!\n"); + mutex_unlock(&wdd->lock); watchdog_ping(wdd); } @@ -444,6 +489,10 @@ static int watchdog_release(struct inode *inode, struct file *file) /* make sure that /dev/watchdog can be re-opened */ clear_bit(WDOG_DEV_OPEN, &wdd->status); + /* Note wdd may be gone after this, do not use after this! */ + if (wdd->ops->unref) + wdd->ops->unref(wdd); + return 0; } @@ -515,6 +564,10 @@ int watchdog_dev_register(struct watchdog_device *watchdog) int watchdog_dev_unregister(struct watchdog_device *watchdog) { + mutex_lock(&watchdog->lock); + set_bit(WDOG_UNREGISTERED, &watchdog->status); + mutex_unlock(&watchdog->lock); + cdev_del(&watchdog->cdev); if (watchdog->id == 0) { misc_deregister(&watchdog_miscdev); |