memcpy(bh->b_data + mh_size, data, copy);
if (copy < sdp->sd_jbsize)
memset(bh->b_data + mh_size + copy, 0,
sdp->sd_jbsize - copy);
memcpy(bh->b_data + mh_size, data, copy);
if (copy < sdp->sd_jbsize)
memset(bh->b_data + mh_size + copy, 0,
sdp->sd_jbsize - copy);