-extern int blkdev_get(struct block_device *, fmode_t);
-extern int blkdev_put(struct block_device *, fmode_t);
-extern int bd_claim(struct block_device *, void *);
-extern void bd_release(struct block_device *);
+extern int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder);
+extern struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
+ void *holder);
+extern struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode,
+ void *holder);
+extern int blkdev_put(struct block_device *bdev, fmode_t mode);