virtio-net: set up xdp for multi buffer packets

When the xdp program sets xdp.frags, which means it can process
multi-buffer packets over larger MTU, so we continue to support xdp.

Signed-off-by: Heng Qi <hengqi@linux.alibaba.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 81d92978cc92fa261cb9dbeb07fbc499d5e84fcf..ba4d5e66a4d71d26da4a6268b3f3bd2ba1ea73ca 100644 (file)
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -3106,9 +3106,9 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
                return -EINVAL;
        }
 
-       if (dev->mtu > max_sz) {
-               NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP");
-               netdev_warn(dev, "XDP requires MTU less than %u\n", max_sz);
+       if (prog && !prog->aux->xdp_has_frags && dev->mtu > max_sz) {
+               NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP without frags");
+               netdev_warn(dev, "single-buffer XDP requires MTU less than %u\n", max_sz);
                return -EINVAL;
        }