USB: Push BKL on open down into the drivers

Straightforward push into the drivers to allow
auditing individual drivers separately

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/media/video/dabusb.c b/drivers/media/video/dabusb.c
index 9b413a3..0f50508 100644
--- a/drivers/media/video/dabusb.c
+++ b/drivers/media/video/dabusb.c
@@ -616,10 +616,12 @@
 {
 	int devnum = iminor(inode);
 	pdabusb_t s;
+	int r;
 
 	if (devnum < DABUSB_MINOR || devnum >= (DABUSB_MINOR + NRDABUSB))
 		return -EIO;
 
+	lock_kernel();
 	s = &dabusb[devnum - DABUSB_MINOR];
 
 	dbg("dabusb_open");
@@ -634,6 +636,7 @@
 		msleep_interruptible(500);
 
 		if (signal_pending (current)) {
+			unlock_kernel();
 			return -EAGAIN;
 		}
 		mutex_lock(&s->mutex);
@@ -641,6 +644,7 @@
 	if (usb_set_interface (s->usbdev, _DABUSB_IF, 1) < 0) {
 		mutex_unlock(&s->mutex);
 		dev_err(&s->usbdev->dev, "set_interface failed\n");
+		unlock_kernel();
 		return -EINVAL;
 	}
 	s->opened = 1;
@@ -649,7 +653,9 @@
 	file->f_pos = 0;
 	file->private_data = s;
 
-	return nonseekable_open(inode, file);
+	r = nonseekable_open(inode, file);
+	unlock_kernel();
+	return r;
 }
 
 static int dabusb_release (struct inode *inode, struct file *file)