+ * Fill the TSO WQE data segments with info on buffers to transmit .
+ *
+ * @param buf
+ * Pointer to the first packet mbuf.
+ * @param txq
+ * Pointer to Tx queue structure.
+ * @param tinfo
+ * Pointer to TSO info to use.
+ * @param dseg
+ * Pointer to the first data segment in the TSO WQE.
+ * @param ctrl
+ * Pointer to the control segment in the TSO WQE.
+ *
+ * @return
+ * 0 on success, negative value upon error.
+ */
+static inline volatile struct mlx4_wqe_ctrl_seg *
+mlx4_tx_burst_fill_tso_dsegs(struct rte_mbuf *buf,
+ struct txq *txq,
+ struct tso_info *tinfo,
+ volatile struct mlx4_wqe_data_seg *dseg,
+ volatile struct mlx4_wqe_ctrl_seg *ctrl)
+{
+ uint32_t lkey;
+ int nb_segs = buf->nb_segs;
+ int nb_segs_txbb;
+ struct mlx4_sq *sq = &txq->msq;
+ struct rte_mbuf *sbuf = buf;
+ struct pv *pv = tinfo->pv;
+ int *pv_counter = &tinfo->pv_counter;
+ volatile struct mlx4_wqe_ctrl_seg *ctrl_next =
+ (volatile struct mlx4_wqe_ctrl_seg *)
+ ((volatile uint8_t *)ctrl + tinfo->wqe_size);
+ uint16_t data_len = sbuf->data_len - tinfo->tso_header_size;
+ uintptr_t data_addr = rte_pktmbuf_mtod_offset(sbuf, uintptr_t,
+ tinfo->tso_header_size);
+
+ do {
+ /* how many dseg entries do we have in the current TXBB ? */
+ nb_segs_txbb = (MLX4_TXBB_SIZE -
+ ((uintptr_t)dseg & (MLX4_TXBB_SIZE - 1))) >>
+ MLX4_SEG_SHIFT;
+ switch (nb_segs_txbb) {
+#ifndef NDEBUG
+ default:
+ /* Should never happen. */
+ rte_panic("%p: Invalid number of SGEs(%d) for a TXBB",
+ (void *)txq, nb_segs_txbb);
+ /* rte_panic never returns. */
+ break;
+#endif /* NDEBUG */
+ case 4:
+ /* Memory region key for this memory pool. */
+ lkey = mlx4_tx_mb2mr(txq, sbuf);
+ if (unlikely(lkey == (uint32_t)-1))
+ goto err;
+ dseg->addr = rte_cpu_to_be_64(data_addr);
+ dseg->lkey = lkey;
+ /*
+ * This data segment starts at the beginning of a new
+ * TXBB, so we need to postpone its byte_count writing
+ * for later.
+ */
+ pv[*pv_counter].dseg = dseg;
+ /*
+ * Zero length segment is treated as inline segment
+ * with zero data.
+ */
+ pv[(*pv_counter)++].val =
+ rte_cpu_to_be_32(data_len ?
+ data_len :
+ 0x80000000);
+ if (--nb_segs == 0)
+ return ctrl_next;
+ /* Prepare next buf info */
+ sbuf = sbuf->next;
+ dseg++;
+ data_len = sbuf->data_len;
+ data_addr = rte_pktmbuf_mtod(sbuf, uintptr_t);
+ /* fallthrough */
+ case 3:
+ lkey = mlx4_tx_mb2mr(txq, sbuf);
+ if (unlikely(lkey == (uint32_t)-1))
+ goto err;
+ mlx4_fill_tx_data_seg(dseg, lkey, data_addr,
+ rte_cpu_to_be_32(data_len ?
+ data_len :
+ 0x80000000));
+ if (--nb_segs == 0)
+ return ctrl_next;
+ /* Prepare next buf info */
+ sbuf = sbuf->next;
+ dseg++;
+ data_len = sbuf->data_len;
+ data_addr = rte_pktmbuf_mtod(sbuf, uintptr_t);
+ /* fallthrough */
+ case 2:
+ lkey = mlx4_tx_mb2mr(txq, sbuf);
+ if (unlikely(lkey == (uint32_t)-1))
+ goto err;
+ mlx4_fill_tx_data_seg(dseg, lkey, data_addr,
+ rte_cpu_to_be_32(data_len ?
+ data_len :
+ 0x80000000));
+ if (--nb_segs == 0)
+ return ctrl_next;
+ /* Prepare next buf info */
+ sbuf = sbuf->next;
+ dseg++;
+ data_len = sbuf->data_len;
+ data_addr = rte_pktmbuf_mtod(sbuf, uintptr_t);
+ /* fallthrough */
+ case 1:
+ lkey = mlx4_tx_mb2mr(txq, sbuf);
+ if (unlikely(lkey == (uint32_t)-1))
+ goto err;
+ mlx4_fill_tx_data_seg(dseg, lkey, data_addr,
+ rte_cpu_to_be_32(data_len ?
+ data_len :
+ 0x80000000));
+ if (--nb_segs == 0)
+ return ctrl_next;
+ /* Prepare next buf info */
+ sbuf = sbuf->next;
+ dseg++;
+ data_len = sbuf->data_len;
+ data_addr = rte_pktmbuf_mtod(sbuf, uintptr_t);
+ /* fallthrough */
+ }
+ /* Wrap dseg if it points at the end of the queue. */
+ if ((volatile uint8_t *)dseg >= sq->eob)
+ dseg = (volatile struct mlx4_wqe_data_seg *)
+ ((volatile uint8_t *)dseg - sq->size);
+ } while (true);
+err:
+ return NULL;
+}
+
+/**
+ * Fill the packet's l2, l3 and l4 headers to the WQE.
+ *
+ * This will be used as the header for each TSO segment that is transmitted.