diff options
Diffstat (limited to 'drivers/media/video/v4l2-dev.c')
| -rw-r--r-- | drivers/media/video/v4l2-dev.c | 76 |
1 files changed, 58 insertions, 18 deletions
diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c index 5a54eabd4c4..a7702e3d149 100644 --- a/drivers/media/video/v4l2-dev.c +++ b/drivers/media/video/v4l2-dev.c @@ -187,33 +187,50 @@ 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; if (!vdev->fops->read) return -EINVAL; - if (!video_is_registered(vdev)) - return -EIO; - return vdev->fops->read(filp, buf, sz, off); + if (vdev->lock) + mutex_lock(vdev->lock); + if (video_is_registered(vdev)) + ret = vdev->fops->read(filp, buf, sz, off); + if (vdev->lock) + mutex_unlock(vdev->lock); + return ret; } 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; if (!vdev->fops->write) return -EINVAL; - if (!video_is_registered(vdev)) - return -EIO; - return vdev->fops->write(filp, buf, sz, off); + if (vdev->lock) + mutex_lock(vdev->lock); + if (video_is_registered(vdev)) + ret = vdev->fops->write(filp, buf, sz, off); + if (vdev->lock) + mutex_unlock(vdev->lock); + return ret; } static unsigned int v4l2_poll(struct file *filp, struct poll_table_struct *poll) { struct video_device *vdev = video_devdata(filp); + int ret = DEFAULT_POLLMASK; - if (!vdev->fops->poll || !video_is_registered(vdev)) - return DEFAULT_POLLMASK; - return vdev->fops->poll(filp, poll); + if (!vdev->fops->poll) + return ret; + if (vdev->lock) + mutex_lock(vdev->lock); + if (video_is_registered(vdev)) + ret = vdev->fops->poll(filp, poll); + if (vdev->lock) + mutex_unlock(vdev->lock); + return ret; } static long v4l2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) @@ -224,7 +241,11 @@ static long v4l2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) if (!vdev->fops->ioctl) return -ENOTTY; if (vdev->fops->unlocked_ioctl) { + if (vdev->lock) + mutex_lock(vdev->lock); ret = vdev->fops->unlocked_ioctl(filp, cmd, arg); + if (vdev->lock) + mutex_unlock(vdev->lock); } else if (vdev->fops->ioctl) { /* TODO: convert all drivers to unlocked_ioctl */ lock_kernel(); @@ -239,10 +260,17 @@ static long v4l2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) static int v4l2_mmap(struct file *filp, struct vm_area_struct *vm) { struct video_device *vdev = video_devdata(filp); + int ret = -ENODEV; - if (!vdev->fops->mmap || !video_is_registered(vdev)) - return -ENODEV; - return vdev->fops->mmap(filp, vm); + if (!vdev->fops->mmap) + return ret; + if (vdev->lock) + mutex_lock(vdev->lock); + if (video_is_registered(vdev)) + ret = vdev->fops->mmap(filp, vm); + if (vdev->lock) + mutex_unlock(vdev->lock); + return ret; } /* Override for the open function */ @@ -254,17 +282,24 @@ static int v4l2_open(struct inode *inode, struct file *filp) /* Check if the video device is available */ mutex_lock(&videodev_lock); vdev = video_devdata(filp); - /* return ENODEV if the video device has been removed - already or if it is not registered anymore. */ - if (vdev == NULL || !video_is_registered(vdev)) { + /* return ENODEV if the video device has already been removed. */ + if (vdev == NULL) { mutex_unlock(&videodev_lock); return -ENODEV; } /* and increase the device refcount */ video_get(vdev); mutex_unlock(&videodev_lock); - if (vdev->fops->open) - ret = vdev->fops->open(filp); + if (vdev->fops->open) { + if (vdev->lock) + mutex_lock(vdev->lock); + if (video_is_registered(vdev)) + ret = vdev->fops->open(filp); + else + ret = -ENODEV; + if (vdev->lock) + mutex_unlock(vdev->lock); + } /* decrease the refcount in case of an error */ if (ret) @@ -278,8 +313,13 @@ static int v4l2_release(struct inode *inode, struct file *filp) struct video_device *vdev = video_devdata(filp); int ret = 0; - if (vdev->fops->release) + if (vdev->fops->release) { + if (vdev->lock) + mutex_lock(vdev->lock); vdev->fops->release(filp); + if (vdev->lock) + mutex_unlock(vdev->lock); + } /* decrease the refcount unconditionally since the release() return value is ignored. */ |