MYRS_MAX_CMD_MBOX
cs->cmd_mbox_size = MYRS_MAX_CMD_MBOX * sizeof(union myrs_cmd_mbox);
cmd_mbox += MYRS_MAX_CMD_MBOX - 1;
(MYRS_MAX_CMD_MBOX * sizeof(union myrs_cmd_mbox)) >> 10;
if (shost->can_queue > MYRS_MAX_CMD_MBOX - 3)
shost->can_queue = MYRS_MAX_CMD_MBOX - 3;