[PATCH] sanitize blkdev_get() and friends

* get rid of fake struct file/struct dentry in __blkdev_get()
* merge __blkdev_get() and do_open()
* get rid of flags argument of blkdev_get()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/partitions/check.c

@@ -485,7 +485,7 @@ void register_disk(struct gendisk *disk)
 		goto exit;
 
 	bdev->bd_invalidated = 1;
-	err = blkdev_get(bdev, FMODE_READ, 0);
+	err = blkdev_get(bdev, FMODE_READ);
 	if (err < 0)
 		goto exit;
 	blkdev_put(bdev, FMODE_READ);