v4l: move BKL down to the driver level.

From: Hans Verkuil <hverkuil@xs4all.nl>

The BKL is now moved from the video_open function in v4l2-dev.c to the
various drivers. It seems about a third of the drivers already has a
lock of some sort protecting the open(), another third uses
video_exclusive_open (yuck!) and the last third required adding the
BKL in their open function.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>

2 files changed, 10 insertions, 1 deletions

diff --git a/linux/drivers/media/video/saa7134/saa7134-empress.c b/linux/drivers/media/video/saa7134/saa7134-empress.c
index 45bd752a9..a454968f7 100644
--- a/linux/drivers/media/video/saa7134/saa7134-empress.c
+++ b/linux/drivers/media/video/saa7134/saa7134-empress.c
@@ -79,9 +79,11 @@ static int ts_open(struct inode *inode, struct file *file)
 	struct saa7134_dev *dev;
 	int err;
 
+	lock_kernel();
 	list_for_each_entry(dev, &saa7134_devlist, devlist)
 		if (dev->empress_dev && dev->empress_dev->minor == minor)
 			goto found;
+	unlock_kernel();
 	return -ENODEV;
  found:
 
@@ -103,6 +105,7 @@ static int ts_open(struct inode *inode, struct file *file)
 done_up:
 	mutex_unlock(&dev->empress_tsq.vb_lock);
 done:
+	unlock_kernel();
 	return err;
 }
 
diff --git a/linux/drivers/media/video/saa7134/saa7134-video.c b/linux/drivers/media/video/saa7134/saa7134-video.c
index 2b4d9c697..547c0401a 100644
--- a/linux/drivers/media/video/saa7134/saa7134-video.c
+++ b/linux/drivers/media/video/saa7134/saa7134-video.c
@@ -1330,6 +1330,8 @@ static int video_open(struct inode *inode, struct file *file)
 	struct saa7134_fh *fh;
 	enum v4l2_buf_type type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 	int radio = 0;
+
+	lock_kernel();
 	list_for_each_entry(dev, &saa7134_devlist, devlist) {
 		if (dev->video_dev && (dev->video_dev->minor == minor))
 			goto found;
@@ -1342,6 +1344,7 @@ static int video_open(struct inode *inode, struct file *file)
 			goto found;
 		}
 	}
+	unlock_kernel();
 	return -ENODEV;
  found:
 
@@ -1350,8 +1353,10 @@ static int video_open(struct inode *inode, struct file *file)
 
 	/* allocate + initialize per filehandle data */
 	fh = kzalloc(sizeof(*fh),GFP_KERNEL);
-	if (NULL == fh)
+	if (NULL == fh) {
+		unlock_kernel();
 		return -ENOMEM;
+	}
 	file->private_data = fh;
 	fh->dev      = dev;
 	fh->radio    = radio;
@@ -1384,6 +1389,7 @@ static int video_open(struct inode *inode, struct file *file)
 		/* switch to video/vbi mode */
 		video_mux(dev,dev->ctl_input);
 	}
+	unlock_kernel();
 	return 0;
 }