diff options
| author | Hans Verkuil <hverkuil@xs4all.nl> | 2010-11-26 06:43:51 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2010-12-01 20:10:18 -0200 |
| commit | 2877842de8cbf6272b0a851cb12587b7dd8c2afb (patch) | |
| tree | 1f04f8d9a4873a5904e5a2f0278f3423cef0d2ca | |
| parent | 78b055be2710b63cb196fc37669f3b662fecc9e4 (diff) | |
[media] v4l2-dev: use mutex_lock_interruptible instead of plain mutex_lock
Where reasonable use mutex_lock_interruptible instead of mutex_lock.
Also fix the poll, read and write error codes when called with an unregistered
device (e.g. after a USB device was disconnected). Poll must return
POLLERR|POLLHUP and read/write must return -ENODEV.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
| -rw-r--r-- | drivers/media/video/v4l2-dev.c | 31 |
1 files changed, 17 insertions, 14 deletions
diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c index 03f7f4670e9..bfd392e2436 100644 --- a/drivers/media/video/v4l2-dev.c +++ b/drivers/media/video/v4l2-dev.c @@ -186,12 +186,12 @@ static ssize_t v4l2_read(struct file *filp, char __user *buf, size_t sz, loff_t *off) { struct video_device *vdev = video_devdata(filp); - int ret = -EIO; + int ret = -ENODEV; if (!vdev->fops->read) return -EINVAL; - if (vdev->lock) - mutex_lock(vdev->lock); + if (vdev->lock && mutex_lock_interruptible(vdev->lock)) + return -ERESTARTSYS; if (video_is_registered(vdev)) ret = vdev->fops->read(filp, buf, sz, off); if (vdev->lock) @@ -203,12 +203,12 @@ static ssize_t v4l2_write(struct file *filp, const char __user *buf, size_t sz, loff_t *off) { struct video_device *vdev = video_devdata(filp); - int ret = -EIO; + int ret = -ENODEV; if (!vdev->fops->write) return -EINVAL; - if (vdev->lock) - mutex_lock(vdev->lock); + if (vdev->lock && mutex_lock_interruptible(vdev->lock)) + return -ERESTARTSYS; if (video_is_registered(vdev)) ret = vdev->fops->write(filp, buf, sz, off); if (vdev->lock) @@ -219,10 +219,10 @@ static ssize_t v4l2_write(struct file *filp, const char __user *buf, static unsigned int v4l2_poll(struct file *filp, struct poll_table_struct *poll) { struct video_device *vdev = video_devdata(filp); - int ret = DEFAULT_POLLMASK; + int ret = POLLERR | POLLHUP; if (!vdev->fops->poll) - return ret; + return DEFAULT_POLLMASK; if (vdev->lock) mutex_lock(vdev->lock); if (video_is_registered(vdev)) @@ -238,8 +238,8 @@ static long v4l2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) int ret = -ENODEV; if (vdev->fops->unlocked_ioctl) { - if (vdev->lock) - mutex_lock(vdev->lock); + if (vdev->lock && mutex_lock_interruptible(vdev->lock)) + return -ERESTARTSYS; if (video_is_registered(vdev)) ret = vdev->fops->unlocked_ioctl(filp, cmd, arg); if (vdev->lock) @@ -265,8 +265,8 @@ static int v4l2_mmap(struct file *filp, struct vm_area_struct *vm) if (!vdev->fops->mmap) return ret; - if (vdev->lock) - mutex_lock(vdev->lock); + if (vdev->lock && mutex_lock_interruptible(vdev->lock)) + return -ERESTARTSYS; if (video_is_registered(vdev)) ret = vdev->fops->mmap(filp, vm); if (vdev->lock) @@ -292,8 +292,10 @@ static int v4l2_open(struct inode *inode, struct file *filp) video_get(vdev); mutex_unlock(&videodev_lock); if (vdev->fops->open) { - if (vdev->lock) - mutex_lock(vdev->lock); + if (vdev->lock && mutex_lock_interruptible(vdev->lock)) { + ret = -ERESTARTSYS; + goto err; + } if (video_is_registered(vdev)) ret = vdev->fops->open(filp); else @@ -302,6 +304,7 @@ static int v4l2_open(struct inode *inode, struct file *filp) mutex_unlock(vdev->lock); } +err: /* decrease the refcount in case of an error */ if (ret) video_put(vdev); |