-/**
- * Posts a single work request to a send queue.
- *
- * @param txq
- * Target Tx queue.
- * @param pkt
- * Packet to transmit.
- *
- * @return
- * 0 on success, negative errno value otherwise.
- */
-static inline int
-mlx4_post_send(struct txq *txq, struct rte_mbuf *pkt)
-{
- struct mlx4_wqe_ctrl_seg *ctrl;
- struct mlx4_wqe_data_seg *dseg;
- struct mlx4_sq *sq = &txq->msq;
- struct rte_mbuf *buf;
- union {
- uint32_t flags;
- uint16_t flags16[2];
- } srcrb;
- uint32_t head_idx = sq->head & sq->txbb_cnt_mask;
- uint32_t lkey;
- uintptr_t addr;
- uint32_t owner_opcode = MLX4_OPCODE_SEND;
- uint32_t byte_count;
- int wqe_real_size;
- int nr_txbbs;
- struct pv *pv = (struct pv *)txq->bounce_buf;
- int pv_counter = 0;
-
- /* Calculate the needed work queue entry size for this packet. */
- wqe_real_size = sizeof(struct mlx4_wqe_ctrl_seg) +
- pkt->nb_segs * sizeof(struct mlx4_wqe_data_seg);
- nr_txbbs = MLX4_SIZE_TO_TXBBS(wqe_real_size);
- /*
- * Check that there is room for this WQE in the send queue and that
- * the WQE size is legal.
- */
- if (((sq->head - sq->tail) + nr_txbbs +
- sq->headroom_txbbs) >= sq->txbb_cnt ||
- nr_txbbs > MLX4_MAX_WQE_TXBBS) {
- return -ENOSPC;
- }
- /* Get the control and data entries of the WQE. */
- ctrl = (struct mlx4_wqe_ctrl_seg *)mlx4_get_send_wqe(sq, head_idx);
- dseg = (struct mlx4_wqe_data_seg *)((uintptr_t)ctrl +
- sizeof(struct mlx4_wqe_ctrl_seg));
- /* Fill the data segments with buffer information. */
- for (buf = pkt; buf != NULL; buf = buf->next, dseg++) {
- addr = rte_pktmbuf_mtod(buf, uintptr_t);
- rte_prefetch0((volatile void *)addr);
- /* Handle WQE wraparound. */
- if (dseg >= (struct mlx4_wqe_data_seg *)sq->eob)
- dseg = (struct mlx4_wqe_data_seg *)sq->buf;
- dseg->addr = rte_cpu_to_be_64(addr);
- /* Memory region key for this memory pool. */
- lkey = mlx4_txq_mp2mr(txq, mlx4_txq_mb2mp(buf));
-#ifndef NDEBUG
- if (unlikely(lkey == (uint32_t)-1)) {
- /* MR does not exist. */
- DEBUG("%p: unable to get MP <-> MR association",
- (void *)txq);
- /*
- * Restamp entry in case of failure.
- * Make sure that size is written correctly
- * Note that we give ownership to the SW, not the HW.
- */
- ctrl->fence_size = (wqe_real_size >> 4) & 0x3f;
- mlx4_txq_stamp_freed_wqe(sq, head_idx,
- (sq->head & sq->txbb_cnt) ? 0 : 1);
- return -EFAULT;
- }
-#endif /* NDEBUG */
- dseg->lkey = rte_cpu_to_be_32(lkey);
- if (likely(buf->data_len)) {
- byte_count = rte_cpu_to_be_32(buf->data_len);
- } else {
- /*
- * Zero length segment is treated as inline segment
- * with zero data.
- */
- byte_count = RTE_BE32(0x80000000);
- }
- /*
- * If the data segment is not at the beginning of a
- * Tx basic block (TXBB) then write the byte count,
- * else postpone the writing to just before updating the
- * control segment.
- */
- if ((uintptr_t)dseg & (uintptr_t)(MLX4_TXBB_SIZE - 1)) {
- /*
- * Need a barrier here before writing the byte_count
- * fields to make sure that all the data is visible
- * before the byte_count field is set.
- * Otherwise, if the segment begins a new cacheline,
- * the HCA prefetcher could grab the 64-byte chunk and
- * get a valid (!= 0xffffffff) byte count but stale
- * data, and end up sending the wrong data.
- */
- rte_io_wmb();
- dseg->byte_count = byte_count;
- } else {
- /*
- * 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;
- pv[pv_counter++].val = byte_count;
- }
- }
- /* Write the first DWORD of each TXBB save earlier. */
- if (pv_counter) {
- /* Need a barrier here before writing the byte_count. */
- rte_io_wmb();
- for (--pv_counter; pv_counter >= 0; pv_counter--)
- pv[pv_counter].dseg->byte_count = pv[pv_counter].val;
- }
- /* Fill the control parameters for this packet. */
- ctrl->fence_size = (wqe_real_size >> 4) & 0x3f;
- /*
- * For raw Ethernet, the SOLICIT flag is used to indicate that no ICRC
- * should be calculated.
- */
- txq->elts_comp_cd -= nr_txbbs;
- if (unlikely(txq->elts_comp_cd <= 0)) {
- txq->elts_comp_cd = txq->elts_comp_cd_init;
- srcrb.flags = RTE_BE32(MLX4_WQE_CTRL_SOLICIT |
- MLX4_WQE_CTRL_CQ_UPDATE);
- } else {
- srcrb.flags = RTE_BE32(MLX4_WQE_CTRL_SOLICIT);
- }
- /* Enable HW checksum offload if requested */
- if (txq->csum &&
- (pkt->ol_flags &
- (PKT_TX_IP_CKSUM | PKT_TX_TCP_CKSUM | PKT_TX_UDP_CKSUM))) {
- const uint64_t is_tunneled = (pkt->ol_flags &
- (PKT_TX_TUNNEL_GRE |
- PKT_TX_TUNNEL_VXLAN));
-
- if (is_tunneled && txq->csum_l2tun) {
- owner_opcode |= MLX4_WQE_CTRL_IIP_HDR_CSUM |
- MLX4_WQE_CTRL_IL4_HDR_CSUM;
- if (pkt->ol_flags & PKT_TX_OUTER_IP_CKSUM)
- srcrb.flags |=
- RTE_BE32(MLX4_WQE_CTRL_IP_HDR_CSUM);
- } else {
- srcrb.flags |= RTE_BE32(MLX4_WQE_CTRL_IP_HDR_CSUM |
- MLX4_WQE_CTRL_TCP_UDP_CSUM);
- }
- }
- if (txq->lb) {
- /*
- * Copy destination MAC address to the WQE, this allows
- * loopback in eSwitch, so that VFs and PF can communicate
- * with each other.
- */
- srcrb.flags16[0] = *(rte_pktmbuf_mtod(pkt, uint16_t *));
- ctrl->imm = *(rte_pktmbuf_mtod_offset(pkt, uint32_t *,
- sizeof(uint16_t)));
- } else {
- ctrl->imm = 0;
- }
- ctrl->srcrb_flags = srcrb.flags;
- /*
- * Make sure descriptor is fully written before
- * setting ownership bit (because HW can start
- * executing as soon as we do).
- */
- rte_wmb();
- ctrl->owner_opcode = rte_cpu_to_be_32(owner_opcode |
- ((sq->head & sq->txbb_cnt) ?
- MLX4_BIT_WQE_OWN : 0));
- sq->head += nr_txbbs;
- return 0;
-}
-