[PATCH net-next 5/6] bpf, nfp: add meta data support

[Daniel Borkmann]

Implement support for transferring XDP meta data into skb for
nfp driver; before calling into the program, xdp.data_meta points
to xdp.data, where on program return with pass verdict, we call
into skb_metadata_set().

Signed-off-by: Daniel Borkmann <dan...@iogearbox.net>
Acked-by: Alexei Starovoitov <a...@kernel.org>
Acked-by: John Fastabend <john.fastab...@gmail.com>
---
 .../net/ethernet/netronome/nfp/nfp_net_common.c    | 40 ++++++++--------------
 1 file changed, 15 insertions(+), 25 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c 
b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index e3a38be..d2f73fe 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -1574,27 +1574,6 @@ static void nfp_net_rx_csum(struct nfp_net_dp *dp,
        return true;
 }
 
-static int nfp_net_run_xdp(struct bpf_prog *prog, void *data, void *hard_start,
-                          unsigned int *off, unsigned int *len)
-{
-       struct xdp_buff xdp;
-       void *orig_data;
-       int ret;
-
-       xdp.data_hard_start = hard_start;
-       xdp.data = data + *off;
-       xdp_set_data_meta_invalid(&xdp);
-       xdp.data_end = data + *off + *len;
-
-       orig_data = xdp.data;
-       ret = bpf_prog_run_xdp(prog, &xdp);
-
-       *len -= xdp.data - orig_data;
-       *off += xdp.data - orig_data;
-
-       return ret;
-}
-
 /**
  * nfp_net_rx() - receive up to @budget packets on @rx_ring
  * @rx_ring:   RX ring to receive from
@@ -1630,6 +1609,7 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, 
int budget)
                struct nfp_meta_parsed meta;
                struct net_device *netdev;
                dma_addr_t new_dma_addr;
+               u32 meta_len_xdp = 0;
                void *new_frag;
 
                idx = D_IDX(rx_ring, rx_ring->rd_p);
@@ -1708,16 +1688,24 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, 
int budget)
 
                if (xdp_prog && !(rxd->rxd.flags & PCIE_DESC_RX_BPF &&
                                  dp->bpf_offload_xdp) && !meta.portid) {
+                       void *orig_data = rxbuf->frag + pkt_off;
                        unsigned int dma_off;
-                       void *hard_start;
+                       struct xdp_buff xdp;
                        int act;
 
-                       hard_start = rxbuf->frag + NFP_NET_RX_BUF_HEADROOM;
+                       xdp.data_hard_start = rxbuf->frag + 
NFP_NET_RX_BUF_HEADROOM;
+                       xdp.data = orig_data;
+                       xdp.data_meta = orig_data;
+                       xdp.data_end = orig_data + pkt_len;
+
+                       act = bpf_prog_run_xdp(xdp_prog, &xdp);
+
+                       pkt_len -= xdp.data - orig_data;
+                       pkt_off += xdp.data - orig_data;
 
-                       act = nfp_net_run_xdp(xdp_prog, rxbuf->frag, hard_start,
-                                             &pkt_off, &pkt_len);
                        switch (act) {
                        case XDP_PASS:
+                               meta_len_xdp = xdp.data - xdp.data_meta;
                                break;
                        case XDP_TX:
                                dma_off = pkt_off - NFP_NET_RX_BUF_HEADROOM;
@@ -1785,6 +1773,8 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, 
int budget)
                if (rxd->rxd.flags & PCIE_DESC_RX_VLAN)
                        __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
                                               le16_to_cpu(rxd->rxd.vlan));
+               if (meta_len_xdp)
+                       skb_metadata_set(skb, meta_len_xdp);
 
                napi_gro_receive(&rx_ring->r_vec->napi, skb);
        }
-- 
1.9.3