net/mlx5e: Introduce wrapper for xdp_buff

Preparation for implementing HW metadata kfuncs. No functional change.

Cc: Tariq Toukan <tariqt@nvidia.com>
Cc: Saeed Mahameed <saeedm@nvidia.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/20230119221536.3349901-16-sdf@google.comSigned-off-by: Martin KaFai Lau <martin.lau@kernel.org>

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

@@ -158,8 +158,9 @@ mlx5e_xmit_xdp_buff(struct mlx5e_xdpsq *sq, struct mlx5e_rq *rq,
 
 /* returns true if packet was consumed by xdp */
 bool mlx5e_xdp_handle(struct mlx5e_rq *rq, struct page *page,
-		      struct bpf_prog *prog, struct xdp_buff *xdp)
+		      struct bpf_prog *prog, struct mlx5e_xdp_buff *mxbuf)
 {
+	struct xdp_buff *xdp = &mxbuf->xdp;
 	u32 act;
 	int err;
 

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

@@ -44,10 +44,14 @@
 	(MLX5E_XDP_INLINE_WQE_MAX_DS_CNT * MLX5_SEND_WQE_DS - \
 	 sizeof(struct mlx5_wqe_inline_seg))
 
+struct mlx5e_xdp_buff {
+	struct xdp_buff xdp;
+};
+
 struct mlx5e_xsk_param;
 int mlx5e_xdp_max_mtu(struct mlx5e_params *params, struct mlx5e_xsk_param *xsk);
 bool mlx5e_xdp_handle(struct mlx5e_rq *rq, struct page *page,
-		      struct bpf_prog *prog, struct xdp_buff *xdp);
+		      struct bpf_prog *prog, struct mlx5e_xdp_buff *mlctx);
 void mlx5e_xdp_mpwqe_complete(struct mlx5e_xdpsq *sq);
 bool mlx5e_poll_xdpsq_cq(struct mlx5e_cq *cq);
 void mlx5e_free_xdpsq_descs(struct mlx5e_xdpsq *sq);

drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c

@@ -8,6 +8,14 @@
 
 /* RX data path */
 
+static struct mlx5e_xdp_buff *xsk_buff_to_mxbuf(struct xdp_buff *xdp)
+{
+	/* mlx5e_xdp_buff shares its layout with xdp_buff_xsk
+	 * and private mlx5e_xdp_buff fields fall into xdp_buff_xsk->cb
+	 */
+	return (struct mlx5e_xdp_buff *)xdp;
+}
+
 int mlx5e_xsk_alloc_rx_mpwqe(struct mlx5e_rq *rq, u16 ix)
 {
 	struct mlx5e_mpw_info *wi = mlx5e_get_mpw_info(rq, ix);
@@ -22,6 +30,7 @@ int mlx5e_xsk_alloc_rx_mpwqe(struct mlx5e_rq *rq, u16 ix)
 		goto err;
 
 	BUILD_BUG_ON(sizeof(wi->alloc_units[0]) != sizeof(wi->alloc_units[0].xsk));
+	XSK_CHECK_PRIV_TYPE(struct mlx5e_xdp_buff);
 	batch = xsk_buff_alloc_batch(rq->xsk_pool, (struct xdp_buff **)wi->alloc_units,
 				     rq->mpwqe.pages_per_wqe);
 
@@ -233,7 +242,7 @@ struct sk_buff *mlx5e_xsk_skb_from_cqe_mpwrq_linear(struct mlx5e_rq *rq,
 						    u32 head_offset,
 						    u32 page_idx)
 {
-	struct xdp_buff *xdp = wi->alloc_units[page_idx].xsk;
+	struct mlx5e_xdp_buff *mxbuf = xsk_buff_to_mxbuf(wi->alloc_units[page_idx].xsk);
 	struct bpf_prog *prog;
 
 	/* Check packet size. Note LRO doesn't use linear SKB */
@@ -249,9 +258,9 @@ struct sk_buff *mlx5e_xsk_skb_from_cqe_mpwrq_linear(struct mlx5e_rq *rq,
 	 */
 	WARN_ON_ONCE(head_offset);
 
-	xsk_buff_set_size(xdp, cqe_bcnt);
-	xsk_buff_dma_sync_for_cpu(xdp, rq->xsk_pool);
-	net_prefetch(xdp->data);
+	xsk_buff_set_size(&mxbuf->xdp, cqe_bcnt);
+	xsk_buff_dma_sync_for_cpu(&mxbuf->xdp, rq->xsk_pool);
+	net_prefetch(mxbuf->xdp.data);
 
 	/* Possible flows:
 	 * - XDP_REDIRECT to XSKMAP:
@@ -269,7 +278,7 @@ struct sk_buff *mlx5e_xsk_skb_from_cqe_mpwrq_linear(struct mlx5e_rq *rq,
 	 */
 
 	prog = rcu_dereference(rq->xdp_prog);
-	if (likely(prog && mlx5e_xdp_handle(rq, NULL, prog, xdp))) {
+	if (likely(prog && mlx5e_xdp_handle(rq, NULL, prog, mxbuf))) {
 		if (likely(__test_and_clear_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags)))
 			__set_bit(page_idx, wi->xdp_xmit_bitmap); /* non-atomic */
 		return NULL; /* page/packet was consumed by XDP */
@@ -278,14 +287,14 @@ struct sk_buff *mlx5e_xsk_skb_from_cqe_mpwrq_linear(struct mlx5e_rq *rq,
 	/* XDP_PASS: copy the data from the UMEM to a new SKB and reuse the
 	 * frame. On SKB allocation failure, NULL is returned.
 	 */
-	return mlx5e_xsk_construct_skb(rq, xdp);
+	return mlx5e_xsk_construct_skb(rq, &mxbuf->xdp);
 }
 
 struct sk_buff *mlx5e_xsk_skb_from_cqe_linear(struct mlx5e_rq *rq,
 					      struct mlx5e_wqe_frag_info *wi,
 					      u32 cqe_bcnt)
 {
-	struct xdp_buff *xdp = wi->au->xsk;
+	struct mlx5e_xdp_buff *mxbuf = xsk_buff_to_mxbuf(wi->au->xsk);
 	struct bpf_prog *prog;
 
 	/* wi->offset is not used in this function, because xdp->data and the
@@ -295,17 +304,17 @@ struct sk_buff *mlx5e_xsk_skb_from_cqe_linear(struct mlx5e_rq *rq,
 	 */
 	WARN_ON_ONCE(wi->offset);
 
-	xsk_buff_set_size(xdp, cqe_bcnt);
-	xsk_buff_dma_sync_for_cpu(xdp, rq->xsk_pool);
-	net_prefetch(xdp->data);
+	xsk_buff_set_size(&mxbuf->xdp, cqe_bcnt);
+	xsk_buff_dma_sync_for_cpu(&mxbuf->xdp, rq->xsk_pool);
+	net_prefetch(mxbuf->xdp.data);
 
 	prog = rcu_dereference(rq->xdp_prog);
-	if (likely(prog && mlx5e_xdp_handle(rq, NULL, prog, xdp)))
+	if (likely(prog && mlx5e_xdp_handle(rq, NULL, prog, mxbuf)))
 		return NULL; /* page/packet was consumed by XDP */
 
 	/* XDP_PASS: copy the data from the UMEM to a new SKB. The frame reuse
 	 * will be handled by mlx5e_free_rx_wqe.
 	 * On SKB allocation failure, NULL is returned.
 	 */
-	return mlx5e_xsk_construct_skb(rq, xdp);
+	return mlx5e_xsk_construct_skb(rq, &mxbuf->xdp);
 }

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

@@ -1575,11 +1575,11 @@ struct sk_buff *mlx5e_build_linear_skb(struct mlx5e_rq *rq, void *va,
 	return skb;
 }
 
-static void mlx5e_fill_xdp_buff(struct mlx5e_rq *rq, void *va, u16 headroom,
-				u32 len, struct xdp_buff *xdp)
+static void mlx5e_fill_mxbuf(struct mlx5e_rq *rq, void *va, u16 headroom,
+			     u32 len, struct mlx5e_xdp_buff *mxbuf)
 {
-	xdp_init_buff(xdp, rq->buff.frame0_sz, &rq->xdp_rxq);
-	xdp_prepare_buff(xdp, va, headroom, len, true);
+	xdp_init_buff(&mxbuf->xdp, rq->buff.frame0_sz, &rq->xdp_rxq);
+	xdp_prepare_buff(&mxbuf->xdp, va, headroom, len, true);
 }
 
 static struct sk_buff *
@@ -1606,16 +1606,16 @@ mlx5e_skb_from_cqe_linear(struct mlx5e_rq *rq, struct mlx5e_wqe_frag_info *wi,
 
 	prog = rcu_dereference(rq->xdp_prog);
 	if (prog) {
-		struct xdp_buff xdp;
+		struct mlx5e_xdp_buff mxbuf;
 
 		net_prefetchw(va); /* xdp_frame data area */
-		mlx5e_fill_xdp_buff(rq, va, rx_headroom, cqe_bcnt, &xdp);
-		if (mlx5e_xdp_handle(rq, au->page, prog, &xdp))
+		mlx5e_fill_mxbuf(rq, va, rx_headroom, cqe_bcnt, &mxbuf);
+		if (mlx5e_xdp_handle(rq, au->page, prog, &mxbuf))
 			return NULL; /* page/packet was consumed by XDP */
 
-		rx_headroom = xdp.data - xdp.data_hard_start;
-		metasize = xdp.data - xdp.data_meta;
-		cqe_bcnt = xdp.data_end - xdp.data;
+		rx_headroom = mxbuf.xdp.data - mxbuf.xdp.data_hard_start;
+		metasize = mxbuf.xdp.data - mxbuf.xdp.data_meta;
+		cqe_bcnt = mxbuf.xdp.data_end - mxbuf.xdp.data;
 	}
 	frag_size = MLX5_SKB_FRAG_SZ(rx_headroom + cqe_bcnt);
 	skb = mlx5e_build_linear_skb(rq, va, frag_size, rx_headroom, cqe_bcnt, metasize);
@@ -1637,9 +1637,9 @@ mlx5e_skb_from_cqe_nonlinear(struct mlx5e_rq *rq, struct mlx5e_wqe_frag_info *wi
 	union mlx5e_alloc_unit *au = wi->au;
 	u16 rx_headroom = rq->buff.headroom;
 	struct skb_shared_info *sinfo;
+	struct mlx5e_xdp_buff mxbuf;
 	u32 frag_consumed_bytes;
 	struct bpf_prog *prog;
-	struct xdp_buff xdp;
 	struct sk_buff *skb;
 	dma_addr_t addr;
 	u32 truesize;
@@ -1654,8 +1654,8 @@ mlx5e_skb_from_cqe_nonlinear(struct mlx5e_rq *rq, struct mlx5e_wqe_frag_info *wi
 	net_prefetchw(va); /* xdp_frame data area */
 	net_prefetch(va + rx_headroom);
 
-	mlx5e_fill_xdp_buff(rq, va, rx_headroom, frag_consumed_bytes, &xdp);
-	sinfo = xdp_get_shared_info_from_buff(&xdp);
+	mlx5e_fill_mxbuf(rq, va, rx_headroom, frag_consumed_bytes, &mxbuf);
+	sinfo = xdp_get_shared_info_from_buff(&mxbuf.xdp);
 	truesize = 0;
 
 	cqe_bcnt -= frag_consumed_bytes;
@@ -1673,13 +1673,13 @@ mlx5e_skb_from_cqe_nonlinear(struct mlx5e_rq *rq, struct mlx5e_wqe_frag_info *wi
 		dma_sync_single_for_cpu(rq->pdev, addr + wi->offset,
 					frag_consumed_bytes, rq->buff.map_dir);
 
-		if (!xdp_buff_has_frags(&xdp)) {
+		if (!xdp_buff_has_frags(&mxbuf.xdp)) {
 			/* Init on the first fragment to avoid cold cache access
 			 * when possible.
 			 */
 			sinfo->nr_frags = 0;
 			sinfo->xdp_frags_size = 0;
-			xdp_buff_set_frags_flag(&xdp);
+			xdp_buff_set_frags_flag(&mxbuf.xdp);
 		}
 
 		frag = &sinfo->frags[sinfo->nr_frags++];
@@ -1688,7 +1688,7 @@ mlx5e_skb_from_cqe_nonlinear(struct mlx5e_rq *rq, struct mlx5e_wqe_frag_info *wi
 		skb_frag_size_set(frag, frag_consumed_bytes);
 
 		if (page_is_pfmemalloc(au->page))
-			xdp_buff_set_frag_pfmemalloc(&xdp);
+			xdp_buff_set_frag_pfmemalloc(&mxbuf.xdp);
 
 		sinfo->xdp_frags_size += frag_consumed_bytes;
 		truesize += frag_info->frag_stride;
@@ -1701,7 +1701,7 @@ mlx5e_skb_from_cqe_nonlinear(struct mlx5e_rq *rq, struct mlx5e_wqe_frag_info *wi
 	au = head_wi->au;
 
 	prog = rcu_dereference(rq->xdp_prog);
-	if (prog && mlx5e_xdp_handle(rq, au->page, prog, &xdp)) {
+	if (prog && mlx5e_xdp_handle(rq, au->page, prog, &mxbuf)) {
 		if (test_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags)) {
 			int i;
 
@@ -1711,22 +1711,22 @@ mlx5e_skb_from_cqe_nonlinear(struct mlx5e_rq *rq, struct mlx5e_wqe_frag_info *wi
 		return NULL; /* page/packet was consumed by XDP */
 	}
 
-	skb = mlx5e_build_linear_skb(rq, xdp.data_hard_start, rq->buff.frame0_sz,
-				     xdp.data - xdp.data_hard_start,
-				     xdp.data_end - xdp.data,
-				     xdp.data - xdp.data_meta);
+	skb = mlx5e_build_linear_skb(rq, mxbuf.xdp.data_hard_start, rq->buff.frame0_sz,
+				     mxbuf.xdp.data - mxbuf.xdp.data_hard_start,
+				     mxbuf.xdp.data_end - mxbuf.xdp.data,
+				     mxbuf.xdp.data - mxbuf.xdp.data_meta);
 	if (unlikely(!skb))
 		return NULL;
 
 	page_ref_inc(au->page);
 
-	if (unlikely(xdp_buff_has_frags(&xdp))) {
+	if (unlikely(xdp_buff_has_frags(&mxbuf.xdp))) {
 		int i;
 
 		/* sinfo->nr_frags is reset by build_skb, calculate again. */
 		xdp_update_skb_shared_info(skb, wi - head_wi - 1,
 					   sinfo->xdp_frags_size, truesize,
-					   xdp_buff_is_frag_pfmemalloc(&xdp));
+					   xdp_buff_is_frag_pfmemalloc(&mxbuf.xdp));
 
 		for (i = 0; i < sinfo->nr_frags; i++) {
 			skb_frag_t *frag = &sinfo->frags[i];
@@ -2007,19 +2007,19 @@ mlx5e_skb_from_cqe_mpwrq_linear(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi,
 
 	prog = rcu_dereference(rq->xdp_prog);
 	if (prog) {
-		struct xdp_buff xdp;
+		struct mlx5e_xdp_buff mxbuf;
 
 		net_prefetchw(va); /* xdp_frame data area */
-		mlx5e_fill_xdp_buff(rq, va, rx_headroom, cqe_bcnt, &xdp);
-		if (mlx5e_xdp_handle(rq, au->page, prog, &xdp)) {
+		mlx5e_fill_mxbuf(rq, va, rx_headroom, cqe_bcnt, &mxbuf);
+		if (mlx5e_xdp_handle(rq, au->page, prog, &mxbuf)) {
 			if (__test_and_clear_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags))
 				__set_bit(page_idx, wi->xdp_xmit_bitmap); /* non-atomic */
 			return NULL; /* page/packet was consumed by XDP */
 		}
 
-		rx_headroom = xdp.data - xdp.data_hard_start;
-		metasize = xdp.data - xdp.data_meta;
-		cqe_bcnt = xdp.data_end - xdp.data;
+		rx_headroom = mxbuf.xdp.data - mxbuf.xdp.data_hard_start;
+		metasize = mxbuf.xdp.data - mxbuf.xdp.data_meta;
+		cqe_bcnt = mxbuf.xdp.data_end - mxbuf.xdp.data;
 	}
 	frag_size = MLX5_SKB_FRAG_SZ(rx_headroom + cqe_bcnt);
 	skb = mlx5e_build_linear_skb(rq, va, frag_size, rx_headroom, cqe_bcnt, metasize);