net/mlx5e: XDP, Add array for WQE info descriptors

Each xdp_wqe_info instance describes the number of data-segments
and WQEBBs of the WQE.
This is useful for a downstream patch that adds support for
Multi-Packet TX WQE feature.
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

drivers/net/ethernet/mellanox/mlx5/core/en.h

@@ -411,6 +411,11 @@ struct mlx5e_xdp_info_fifo {
 	u32 mask;
 };
 
+struct mlx5e_xdp_wqe_info {
+	u8 num_wqebbs;
+	u8 num_ds;
+};
+
 struct mlx5e_xdpsq {
 	/* data path */
 
@@ -430,6 +435,7 @@ struct mlx5e_xdpsq {
 	struct mlx5_wq_cyc         wq;
 	struct mlx5e_xdpsq_stats  *stats;
 	struct {
+		struct mlx5e_xdp_wqe_info *wqe_info;
 		struct mlx5e_xdp_info_fifo xdpi_fifo;
 	} db;
 	void __iomem              *uar_map;

drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c

@@ -199,11 +199,18 @@ bool mlx5e_poll_xdpsq_cq(struct mlx5e_cq *cq, struct mlx5e_rq *rq)
 					 get_cqe_opcode(cqe));
 
 		do {
-			struct mlx5e_xdp_info xdpi =
-				mlx5e_xdpi_fifo_pop(xdpi_fifo);
+			struct mlx5e_xdp_wqe_info *wi;
+			u16 ci, j;
 
 			last_wqe = (sqcc == wqe_counter);
-			sqcc++;
+			ci = mlx5_wq_cyc_ctr2ix(&sq->wq, sqcc);
+			wi = &sq->db.wqe_info[ci];
+
+			sqcc += wi->num_wqebbs;
+
+			for (j = 0; j < wi->num_ds; j++) {
+				struct mlx5e_xdp_info xdpi =
+					mlx5e_xdpi_fifo_pop(xdpi_fifo);
 
 				if (is_redirect) {
 					xdp_return_frame(xdpi.xdpf);
@@ -213,6 +220,7 @@ bool mlx5e_poll_xdpsq_cq(struct mlx5e_cq *cq, struct mlx5e_rq *rq)
 					/* Recycle RX page */
 					mlx5e_page_release(rq, &xdpi.di, true);
 				}
+			}
 		} while (!last_wqe);
 	} while ((++i < MLX5E_TX_CQ_POLL_BUDGET) && (cqe = mlx5_cqwq_get_cqe(&cq->wq)));
 
@@ -233,11 +241,18 @@ void mlx5e_free_xdpsq_descs(struct mlx5e_xdpsq *sq, struct mlx5e_rq *rq)
 	bool is_redirect = !rq;
 
 	while (sq->cc != sq->pc) {
+		struct mlx5e_xdp_wqe_info *wi;
+		u16 ci, i;
+
+		ci = mlx5_wq_cyc_ctr2ix(&sq->wq, sq->cc);
+		wi = &sq->db.wqe_info[ci];
+
+		sq->cc += wi->num_wqebbs;
+
+		for (i = 0; i < wi->num_ds; i++) {
 			struct mlx5e_xdp_info xdpi =
 				mlx5e_xdpi_fifo_pop(xdpi_fifo);
 
-		sq->cc++;
-
 			if (is_redirect) {
 				xdp_return_frame(xdpi.xdpf);
 				dma_unmap_single(sq->pdev, xdpi.dma_addr,
@@ -247,6 +262,7 @@ void mlx5e_free_xdpsq_descs(struct mlx5e_xdpsq *sq, struct mlx5e_rq *rq)
 				mlx5e_page_release(rq, &xdpi.di, false);
 			}
 		}
+	}
 }
 
 int mlx5e_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,

drivers/net/ethernet/mellanox/mlx5/core/en_main.c

@@ -993,6 +993,7 @@ static void mlx5e_close_rq(struct mlx5e_rq *rq)
 static void mlx5e_free_xdpsq_db(struct mlx5e_xdpsq *sq)
 {
 	kvfree(sq->db.xdpi_fifo.xi);
+	kvfree(sq->db.wqe_info);
 }
 
 static int mlx5e_alloc_xdpsq_fifo(struct mlx5e_xdpsq *sq, int numa)
@@ -1015,8 +1016,14 @@ static int mlx5e_alloc_xdpsq_fifo(struct mlx5e_xdpsq *sq, int numa)
 
 static int mlx5e_alloc_xdpsq_db(struct mlx5e_xdpsq *sq, int numa)
 {
+	int wq_sz = mlx5_wq_cyc_get_size(&sq->wq);
 	int err;
 
+	sq->db.wqe_info = kvzalloc_node(sizeof(*sq->db.wqe_info) * wq_sz,
+					GFP_KERNEL, numa);
+	if (!sq->db.wqe_info)
+		return -ENOMEM;
+
 	err = mlx5e_alloc_xdpsq_fifo(sq, numa);
 	if (err) {
 		mlx5e_free_xdpsq_db(sq);
@@ -1606,6 +1613,7 @@ static int mlx5e_open_xdpsq(struct mlx5e_channel *c,
 
 	/* Pre initialize fixed WQE fields */
 	for (i = 0; i < mlx5_wq_cyc_get_size(&sq->wq); i++) {
+		struct mlx5e_xdp_wqe_info *wi  = &sq->db.wqe_info[i];
 		struct mlx5e_tx_wqe      *wqe  = mlx5_wq_cyc_get_wqe(&sq->wq, i);
 		struct mlx5_wqe_ctrl_seg *cseg = &wqe->ctrl;
 		struct mlx5_wqe_eth_seg  *eseg = &wqe->eth;
@@ -1616,6 +1624,9 @@ static int mlx5e_open_xdpsq(struct mlx5e_channel *c,
 
 		dseg = (struct mlx5_wqe_data_seg *)cseg + (ds_cnt - 1);
 		dseg->lkey = sq->mkey_be;
+
+		wi->num_wqebbs = 1;
+		wi->num_ds     = 1;
 	}
 
 	return 0;