ALGORITHM_PARITY_0
{"raid4", "raid4 (dedicated first parity disk)", 1, 2, 5, ALGORITHM_PARITY_0}, /* raid4 layout = raid5_0 */
case ALGORITHM_PARITY_0:
case ALGORITHM_PARITY_0:
case ALGORITHM_PARITY_0:
case ALGORITHM_PARITY_0:
case ALGORITHM_PARITY_0:
new_layout = ALGORITHM_PARITY_0;
case ALGORITHM_PARITY_0: