gve: Add Rx HWTS metadata to AF_XDP ZC mode

By overlaying the struct gve_xdp_buff on top of the struct xdp_buff_xsk
that AF_XDP utilizes, the driver records the 32 bit timestamp via the
completion descriptor and the cached 64 bit NIC timestamp via gve_priv.

The driver's implementation of xmo_rx_timestamp extends the timestamp to
the full and up to date 64 bit timestamp and returns it to the user.

gve_rx_xsk_dqo is modified to accept a pointer to the completion
descriptor and no longer takes a buf_len explicitly as it can be pulled
out of the descriptor.

With this patch gve now supports bpf_xdp_metadata_rx_timestamp.

Signed-off-by: Tim Hostetler <thostet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Harshitha Ramamurthy <hramamurthy@google.com>
Signed-off-by: Joshua Washington <joshwash@google.com>
Link: https://patch.msgid.link/20251114211146.292068-5-joshwash@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/drivers/net/ethernet/google/gve/gve_main.c b/drivers/net/ethernet/google/gve/gve_main.c
index 2b41a42fb51695fffbb61d6d2f5971759a2c152f..a5a2b18d309b8c308523aa9b44e1c599d42fedf1 100644 (file)
--- a/drivers/net/ethernet/google/gve/gve_main.c
+++ b/drivers/net/ethernet/google/gve/gve_main.c
@@ -2348,6 +2348,10 @@ static void gve_set_netdev_xdp_features(struct gve_priv *priv)
        xdp_set_features_flag_locked(priv->dev, xdp_features);
 }
 
+static const struct xdp_metadata_ops gve_xdp_metadata_ops = {
+       .xmo_rx_timestamp       = gve_xdp_rx_timestamp,
+};
+
 static int gve_init_priv(struct gve_priv *priv, bool skip_describe_device)
 {
        int num_ntfy;
@@ -2443,6 +2447,9 @@ setup_device:
        }
 
        gve_set_netdev_xdp_features(priv);
+       if (!gve_is_gqi(priv))
+               priv->dev->xdp_metadata_ops = &gve_xdp_metadata_ops;
+
        err = gve_setup_device_resources(priv);
        if (err)
                goto err_free_xsk_bitmap;

diff --git a/drivers/net/ethernet/google/gve/gve_rx_dqo.c b/drivers/net/ethernet/google/gve/gve_rx_dqo.c
index f20d1b1d06e681549a7008143801fb075c487832..f1bd8f5d573239088ef57ab1b223d8b31899e864 100644 (file)
--- a/drivers/net/ethernet/google/gve/gve_rx_dqo.c
+++ b/drivers/net/ethernet/google/gve/gve_rx_dqo.c
@@ -240,6 +240,11 @@ int gve_rx_alloc_ring_dqo(struct gve_priv *priv,
                rx->rx_headroom = 0;
        }
 
+       /* struct gve_xdp_buff is overlaid on struct xdp_buff_xsk and utilizes
+        * the 24 byte field cb to store gve specific data.
+        */
+       XSK_CHECK_PRIV_TYPE(struct gve_xdp_buff);
+
        rx->dqo.num_buf_states = cfg->raw_addressing ? buffer_queue_slots :
                gve_get_rx_pages_per_qpl_dqo(cfg->ring_size);
        rx->dqo.buf_states = kvcalloc_node(rx->dqo.num_buf_states,
@@ -701,16 +706,23 @@ err:
 }
 
 static int gve_rx_xsk_dqo(struct napi_struct *napi, struct gve_rx_ring *rx,
-                         struct gve_rx_buf_state_dqo *buf_state, int buf_len,
+                         const struct gve_rx_compl_desc_dqo *compl_desc,
+                         struct gve_rx_buf_state_dqo *buf_state,
                          struct bpf_prog *xprog)
 {
        struct xdp_buff *xdp = buf_state->xsk_buff;
+       int buf_len = compl_desc->packet_len;
        struct gve_priv *priv = rx->gve;
+       struct gve_xdp_buff *gve_xdp;
        int xdp_act;
 
        xdp->data_end = xdp->data + buf_len;
        xsk_buff_dma_sync_for_cpu(xdp);
 
+       gve_xdp = (void *)xdp;
+       gve_xdp->gve = priv;
+       gve_xdp->compl_desc = compl_desc;
+
        if (xprog) {
                xdp_act = bpf_prog_run_xdp(xprog, xdp);
                buf_len = xdp->data_end - xdp->data;
@@ -800,7 +812,7 @@ static int gve_rx_dqo(struct napi_struct *napi, struct gve_rx_ring *rx,
 
        xprog = READ_ONCE(priv->xdp_prog);
        if (buf_state->xsk_buff)
-               return gve_rx_xsk_dqo(napi, rx, buf_state, buf_len, xprog);
+               return gve_rx_xsk_dqo(napi, rx, compl_desc, buf_state, xprog);
 
        /* Page might have not been used for awhile and was likely last written
         * by a different thread.