net: netdevsim: hook in XDP handling

Add basic XDP support by hooking in do_xdp_generic().
This should be enough to validate most basic XDP tests.

Signed-off-by: Mohsin Bashir <mohsin.bashr@gmail.com>
Link: https://patch.msgid.link/20250719083059.3209169-2-mohsin.bashr@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c
index 611e7f65291cd9273880af747e17f28adefe980f..a7628f5c09af71534ed210defab41b68d808d83b 100644 (file)
--- a/drivers/net/netdevsim/netdev.c
+++ b/drivers/net/netdevsim/netdev.c
@@ -387,15 +387,34 @@ static int nsim_get_iflink(const struct net_device *dev)
 static int nsim_rcv(struct nsim_rq *rq, int budget)
 {
        struct net_device *dev = rq->napi.dev;
+       struct bpf_prog *xdp_prog;
+       struct netdevsim *ns;
        struct sk_buff *skb;
        unsigned int skblen;
        int i, ret;
 
+       ns = netdev_priv(dev);
+       xdp_prog = READ_ONCE(ns->xdp.prog);
+
        for (i = 0; i < budget; i++) {
                if (skb_queue_empty(&rq->skb_queue))
                        break;
 
                skb = skb_dequeue(&rq->skb_queue);
+
+               if (xdp_prog) {
+                       /* skb might be freed directly by XDP, save the len */
+                       skblen = skb->len;
+
+                       if (skb->ip_summed == CHECKSUM_PARTIAL)
+                               skb_checksum_help(skb);
+                       ret = do_xdp_generic(xdp_prog, &skb);
+                       if (ret != XDP_PASS) {
+                               dev_dstats_rx_add(dev, skblen);
+                               continue;
+                       }
+               }
+
                /* skb might be discard at netif_receive_skb, save the len */
                skblen = skb->len;
                skb_mark_napi_id(skb, &rq->napi);
@@ -936,7 +955,7 @@ static void nsim_setup(struct net_device *dev)
                            NETIF_F_TSO;
        dev->pcpu_stat_type = NETDEV_PCPU_STAT_DSTATS;
        dev->max_mtu = ETH_MAX_MTU;
-       dev->xdp_features = NETDEV_XDP_ACT_HW_OFFLOAD;
+       dev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_HW_OFFLOAD;
 }
 
 static int nsim_queue_init(struct netdevsim *ns)