static int tapeblock_open(struct block_device *, fmode_t);
static int tapeblock_release(struct gendisk *, fmode_t);
static int tapeblock_medium_changed(struct gendisk *);
static int tapeblock_open(struct block_device *, fmode_t);
static int tapeblock_release(struct gendisk *, fmode_t);
static int tapeblock_medium_changed(struct gendisk *);