Re: [PATCH net-next] net: mlx4: Add support for XDP_REDIRECT

Signed-off-by: Joshua Roys <redacted>
---
 drivers/net/ethernet/mellanox/mlx4/en_rx.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

This is a pattern-match commit, based off of the mlx4 XDP_TX and other
drivers' XDP_REDIRECT enablement patches. The goal was to get AF_XDP
working in VPP and this was successful. Tested with a CX3.

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index 7f6d3b82c29b..557d7daac2d3 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c

@@ -669,6 +669,7 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
        struct bpf_prog *xdp_prog;
        int cq_ring = cq->ring;
        bool doorbell_pending;
+       bool xdp_redir_flush;
        struct mlx4_cqe *cqe;
        struct xdp_buff xdp;
        int polled = 0;

@@ -682,6 +683,7 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
        xdp_prog = rcu_dereference_bh(ring->xdp_prog);
        xdp_init_buff(&xdp, priv->frag_info[0].frag_stride, &ring->xdp_rxq);
        doorbell_pending = false;
+       xdp_redir_flush = false;

        /* We assume a 1:1 mapping between CQEs and Rx descriptors, so Rx
         * descriptor offset can be deduced from the CQE index instead of

@@ -790,6 +792,14 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
                        switch (act) {
                        case XDP_PASS:
                                break;
+                       case XDP_REDIRECT:
+                               if (xdp_do_redirect(dev, &xdp, xdp_prog) >= 0) {
+                                       xdp_redir_flush = true;
+                                       frags[0].page = NULL;
+                                       goto next;
+                               }
+                               trace_xdp_exception(dev, xdp_prog, act);
+                               goto xdp_drop_no_cnt;
                        case XDP_TX:
                                if (likely(!mlx4_en_xmit_frame(ring, frags, priv,
                                                        length, cq_ring,

@@ -897,6 +907,9 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
                        break;
        }

+       if (xdp_redir_flush)
+               xdp_do_flush();
+
        if (likely(polled)) {
                if (doorbell_pending) {
                        priv->tx_cq[TX_XDP][cq_ring]->xdp_busy = true;
--

2.31.1