+static int build_lso_seg(struct mlx4_lso_seg *wqe, struct ib_send_wr *wr,
+ struct mlx4_ib_qp *qp, unsigned *lso_seg_len)
+{
+ unsigned halign = ALIGN(sizeof *wqe + wr->wr.ud.hlen, 16);
+
+ /*
+ * This is a temporary limitation and will be removed in
+ * a forthcoming FW release:
+ */
+ if (unlikely(halign > 64))
+ return -EINVAL;
+
+ if (unlikely(!(qp->flags & MLX4_IB_QP_LSO) &&
+ wr->num_sge > qp->sq.max_gs - (halign >> 4)))
+ return -EINVAL;
+
+ memcpy(wqe->header, wr->wr.ud.header, wr->wr.ud.hlen);
+
+ /* make sure LSO header is written before overwriting stamping */
+ wmb();
+
+ wqe->mss_hdr_size = cpu_to_be32((wr->wr.ud.mss - wr->wr.ud.hlen) << 16 |
+ wr->wr.ud.hlen);
+
+ *lso_seg_len = halign;
+ return 0;
+}
+