BLKROSET
#define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */
#define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */
#define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */