sd_prin_readresv_t
sd_prin_readresv_t *in;
data_len += (sizeof (sd_prin_readresv_t) - sizeof (caddr_t));
in = (sd_prin_readresv_t *)data_bufp;
sd_prin_readresv_t *scsi_resv;
sizeof (sd_prin_readresv_t) - sizeof (caddr_t) +
scsi_resv = (sd_prin_readresv_t *)VD_SCSI_DATA_IN(vd_scsi);