net/mlx5e: Add support for using xdp->data_meta

Add support for using xdp->data_meta for cross-program communication

Pass "true" to the last argument of xdp_prepare_buff().

After SKB is built, call skb_metadata_set() if metadata was pushed.
Signed-off-by: Alex Liu <liualex@fb.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

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

@@ -1489,7 +1489,7 @@ static inline void mlx5e_complete_rx_cqe(struct mlx5e_rq *rq,
 static inline
 struct sk_buff *mlx5e_build_linear_skb(struct mlx5e_rq *rq, void *va,
 				       u32 frag_size, u16 headroom,
-				       u32 cqe_bcnt)
+				       u32 cqe_bcnt, u32 metasize)
 {
 	struct sk_buff *skb = build_skb(va, frag_size);
 
@@ -1501,6 +1501,9 @@ struct sk_buff *mlx5e_build_linear_skb(struct mlx5e_rq *rq, void *va,
 	skb_reserve(skb, headroom);
 	skb_put(skb, cqe_bcnt);
 
+	if (metasize)
+		skb_metadata_set(skb, metasize);
+
 	return skb;
 }
 
@@ -1508,7 +1511,7 @@ static void mlx5e_fill_xdp_buff(struct mlx5e_rq *rq, void *va, u16 headroom,
 				u32 len, struct xdp_buff *xdp)
 {
 	xdp_init_buff(xdp, rq->buff.frame0_sz, &rq->xdp_rxq);
-	xdp_prepare_buff(xdp, va, headroom, len, false);
+	xdp_prepare_buff(xdp, va, headroom, len, true);
 }
 
 static struct sk_buff *
@@ -1521,6 +1524,7 @@ mlx5e_skb_from_cqe_linear(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe,
 	struct sk_buff *skb;
 	void *va, *data;
 	u32 frag_size;
+	u32 metasize;
 
 	va             = page_address(di->page) + wi->offset;
 	data           = va + rx_headroom;
@@ -1537,7 +1541,8 @@ mlx5e_skb_from_cqe_linear(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe,
 
 	rx_headroom = xdp.data - xdp.data_hard_start;
 	frag_size = MLX5_SKB_FRAG_SZ(rx_headroom + cqe_bcnt);
-	skb = mlx5e_build_linear_skb(rq, va, frag_size, rx_headroom, cqe_bcnt);
+	metasize = xdp.data - xdp.data_meta;
+	skb = mlx5e_build_linear_skb(rq, va, frag_size, rx_headroom, cqe_bcnt, metasize);
 	if (unlikely(!skb))
 		return NULL;
 
@@ -1836,6 +1841,7 @@ mlx5e_skb_from_cqe_mpwrq_linear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi,
 	struct sk_buff *skb;
 	void *va, *data;
 	u32 frag_size;
+	u32 metasize;
 
 	/* Check packet size. Note LRO doesn't use linear SKB */
 	if (unlikely(cqe_bcnt > rq->hw_mtu)) {
@@ -1861,7 +1867,8 @@ mlx5e_skb_from_cqe_mpwrq_linear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi,
 
 	rx_headroom = xdp.data - xdp.data_hard_start;
 	frag_size = MLX5_SKB_FRAG_SZ(rx_headroom + cqe_bcnt32);
-	skb = mlx5e_build_linear_skb(rq, va, frag_size, rx_headroom, cqe_bcnt32);
+	metasize = xdp.data - xdp.data_meta;
+	skb = mlx5e_build_linear_skb(rq, va, frag_size, rx_headroom, cqe_bcnt32, metasize);
 	if (unlikely(!skb))
 		return NULL;
 
@@ -1892,7 +1899,7 @@ mlx5e_skb_from_cqe_shampo(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi,
 		dma_sync_single_range_for_cpu(rq->pdev, head->addr, 0, frag_size, DMA_FROM_DEVICE);
 		prefetchw(hdr);
 		prefetch(data);
-		skb = mlx5e_build_linear_skb(rq, hdr, frag_size, rx_headroom, head_size);
+		skb = mlx5e_build_linear_skb(rq, hdr, frag_size, rx_headroom, head_size, 0);
 
 		if (unlikely(!skb))
 			return NULL;