OPA_16B_DLID_MASK
lrh2 = (lrh2 & ~OPA_16B_DLID_MASK) |
(((hdr->lrh[2] & OPA_16B_DLID_MASK) >>
h[2] |= ((dlid >> (20 - OPA_16B_DLID_HIGH_SHFT)) & OPA_16B_DLID_MASK);