net/mlx4_en: Introduce wrapper for xdp_buff

No functional changes. Boilerplate to allow stuffing more data after xdp_buff.

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
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230119221536.3349901-13-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index 8f762fc..014a80a 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -661,9 +661,14 @@ static int check_csum(struct mlx4_cqe *cqe, struct sk_buff *skb, void *va,
 #define MLX4_CQE_STATUS_IP_ANY (MLX4_CQE_STATUS_IPV4)
 #endif
 
+struct mlx4_en_xdp_buff {
+       struct xdp_buff xdp;
+};
+
 int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int budget)
 {
        struct mlx4_en_priv *priv = netdev_priv(dev);
+       struct mlx4_en_xdp_buff mxbuf = {};
        int factor = priv->cqe_factor;
        struct mlx4_en_rx_ring *ring;
        struct bpf_prog *xdp_prog;
@@ -671,7 +676,6 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
        bool doorbell_pending;
        bool xdp_redir_flush;
        struct mlx4_cqe *cqe;
-       struct xdp_buff xdp;
        int polled = 0;
        int index;
 
@@ -681,7 +685,7 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
        ring = priv->rx_ring[cq_ring];
 
        xdp_prog = rcu_dereference_bh(ring->xdp_prog);
-       xdp_init_buff(&xdp, priv->frag_info[0].frag_stride, &ring->xdp_rxq);
+       xdp_init_buff(&mxbuf.xdp, priv->frag_info[0].frag_stride, &ring->xdp_rxq);
        doorbell_pending = false;
        xdp_redir_flush = false;
 
@@ -776,24 +780,24 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
                                                priv->frag_info[0].frag_size,
                                                DMA_FROM_DEVICE);
 
-                       xdp_prepare_buff(&xdp, va - frags[0].page_offset,
+                       xdp_prepare_buff(&mxbuf.xdp, va - frags[0].page_offset,
                                         frags[0].page_offset, length, false);
-                       orig_data = xdp.data;
+                       orig_data = mxbuf.xdp.data;
 
-                       act = bpf_prog_run_xdp(xdp_prog, &xdp);
+                       act = bpf_prog_run_xdp(xdp_prog, &mxbuf.xdp);
 
-                       length = xdp.data_end - xdp.data;
-                       if (xdp.data != orig_data) {
-                               frags[0].page_offset = xdp.data -
-                                       xdp.data_hard_start;
-                               va = xdp.data;
+                       length = mxbuf.xdp.data_end - mxbuf.xdp.data;
+                       if (mxbuf.xdp.data != orig_data) {
+                               frags[0].page_offset = mxbuf.xdp.data -
+                                       mxbuf.xdp.data_hard_start;
+                               va = mxbuf.xdp.data;
                        }
 
                        switch (act) {
                        case XDP_PASS:
                                break;
                        case XDP_REDIRECT:
-                               if (likely(!xdp_do_redirect(dev, &xdp, xdp_prog))) {
+                               if (likely(!xdp_do_redirect(dev, &mxbuf.xdp, xdp_prog))) {
                                        ring->xdp_redirect++;
                                        xdp_redir_flush = true;
                                        frags[0].page = NULL;