+ const uint32_t strd_n = 1 << rxq->strd_num_n;
+ struct mlx5_mprq_buf *rep = rxq->mprq_repl;
+ volatile struct mlx5_wqe_data_seg *wqe =
+ &((volatile struct mlx5_wqe_mprq *)rxq->wqes)[rq_idx].dseg;
+ struct mlx5_mprq_buf *buf = (*rxq->mprq_bufs)[rq_idx];
+ void *addr;
+
+ if (__atomic_load_n(&buf->refcnt, __ATOMIC_RELAXED) > 1) {
+ MLX5_ASSERT(rep != NULL);
+ /* Replace MPRQ buf. */
+ (*rxq->mprq_bufs)[rq_idx] = rep;
+ /* Replace WQE. */
+ addr = mlx5_mprq_buf_addr(rep, strd_n);
+ wqe->addr = rte_cpu_to_be_64((uintptr_t)addr);
+ /* If there's only one MR, no need to replace LKey in WQE. */
+ if (unlikely(mlx5_mr_btree_len(&rxq->mr_ctrl.cache_bh) > 1))
+ wqe->lkey = mlx5_rx_addr2mr(rxq, (uintptr_t)addr);
+ /* Stash a mbuf for next replacement. */
+ if (likely(!rte_mempool_get(rxq->mprq_mp, (void **)&rep)))
+ rxq->mprq_repl = rep;
+ else
+ rxq->mprq_repl = NULL;
+ /* Release the old buffer. */
+ mlx5_mprq_buf_free(buf);
+ } else if (unlikely(rxq->mprq_repl == NULL)) {
+ struct mlx5_mprq_buf *rep;
+
+ /*
+ * Currently, the MPRQ mempool is out of buffer
+ * and doing memcpy regardless of the size of Rx
+ * packet. Retry allocation to get back to
+ * normal.
+ */
+ if (!rte_mempool_get(rxq->mprq_mp, (void **)&rep))
+ rxq->mprq_repl = rep;
+ }
+}
+
+/**
+ * Attach or copy MPRQ buffer content to a packet.
+ *
+ * @param rxq
+ * Pointer to Rx queue structure.
+ * @param pkt
+ * Pointer to a packet to fill.
+ * @param len
+ * Packet length.
+ * @param buf
+ * Pointer to a MPRQ buffer to take the data from.
+ * @param strd_idx
+ * Stride index to start from.
+ * @param strd_cnt
+ * Number of strides to consume.
+ */
+static __rte_always_inline enum mlx5_rqx_code
+mprq_buf_to_pkt(struct mlx5_rxq_data *rxq, struct rte_mbuf *pkt, uint32_t len,
+ struct mlx5_mprq_buf *buf, uint16_t strd_idx, uint16_t strd_cnt)
+{
+ const uint32_t strd_n = 1 << rxq->strd_num_n;
+ const uint16_t strd_sz = 1 << rxq->strd_sz_n;
+ const uint16_t strd_shift =
+ MLX5_MPRQ_STRIDE_SHIFT_BYTE * rxq->strd_shift_en;
+ const int32_t hdrm_overlap =
+ len + RTE_PKTMBUF_HEADROOM - strd_cnt * strd_sz;
+ const uint32_t offset = strd_idx * strd_sz + strd_shift;
+ void *addr = RTE_PTR_ADD(mlx5_mprq_buf_addr(buf, strd_n), offset);
+
+ /*
+ * Memcpy packets to the target mbuf if:
+ * - The size of packet is smaller than mprq_max_memcpy_len.
+ * - Out of buffer in the Mempool for Multi-Packet RQ.
+ * - The packet's stride overlaps a headroom and scatter is off.
+ */
+ if (len <= rxq->mprq_max_memcpy_len ||
+ rxq->mprq_repl == NULL ||
+ (hdrm_overlap > 0 && !rxq->strd_scatter_en)) {
+ if (likely(len <=
+ (uint32_t)(pkt->buf_len - RTE_PKTMBUF_HEADROOM))) {
+ rte_memcpy(rte_pktmbuf_mtod(pkt, void *),
+ addr, len);
+ DATA_LEN(pkt) = len;
+ } else if (rxq->strd_scatter_en) {
+ struct rte_mbuf *prev = pkt;
+ uint32_t seg_len = RTE_MIN(len, (uint32_t)
+ (pkt->buf_len - RTE_PKTMBUF_HEADROOM));
+ uint32_t rem_len = len - seg_len;
+
+ rte_memcpy(rte_pktmbuf_mtod(pkt, void *),
+ addr, seg_len);
+ DATA_LEN(pkt) = seg_len;
+ while (rem_len) {
+ struct rte_mbuf *next =
+ rte_pktmbuf_alloc(rxq->mp);
+
+ if (unlikely(next == NULL))
+ return MLX5_RXQ_CODE_NOMBUF;
+ NEXT(prev) = next;
+ SET_DATA_OFF(next, 0);
+ addr = RTE_PTR_ADD(addr, seg_len);
+ seg_len = RTE_MIN(rem_len, (uint32_t)
+ (next->buf_len - RTE_PKTMBUF_HEADROOM));
+ rte_memcpy
+ (rte_pktmbuf_mtod(next, void *),
+ addr, seg_len);
+ DATA_LEN(next) = seg_len;
+ rem_len -= seg_len;
+ prev = next;
+ ++NB_SEGS(pkt);
+ }