[PATCH v1 net-next 2/3] virtio_net: enable outer nw header offset support.

[Kommula Shiva Shankar]

If outer network header feature is set, update header offset
in ingress and egress path.

If feature is not set, reset header offset to zero.

Signed-off-by: Kommula Shiva Shankar <kshan...@marvell.com>
---
 drivers/net/virtio_net.c | 23 +++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 7da5a37917e9..0b60cbbb3d33 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -451,6 +451,9 @@ struct virtnet_info {
 
        bool rx_tnl_csum;
 
+       /* Outer network header support */
+       bool out_net_hdr_negotiated;
+
        /* Is delayed refill enabled? */
        bool refill_enabled;
 
@@ -511,6 +514,7 @@ struct virtio_net_common_hdr {
                struct virtio_net_hdr_mrg_rxbuf mrg_hdr;
                struct virtio_net_hdr_v1_hash hash_v1_hdr;
                struct virtio_net_hdr_v1_hash_tunnel tnl_hdr;
+               struct virtio_net_hdr_v1_hash_tunnel_out_net_hdr out_net_hdr;
        };
 };
 
@@ -2576,8 +2580,8 @@ static void virtnet_receive_done(struct virtnet_info *vi, 
struct receive_queue *
        hdr->hdr.flags = flags;
        if (virtio_net_handle_csum_offload(skb, &hdr->hdr, vi->rx_tnl_csum)) {
                net_warn_ratelimited("%s: bad csum: flags: %x, gso_type: %x 
rx_tnl_csum %d\n",
-                                    dev->name, hdr->hdr.flags,
-                                    hdr->hdr.gso_type, vi->rx_tnl_csum);
+                               dev->name, hdr->hdr.flags,
+                               hdr->hdr.gso_type, vi->rx_tnl_csum);
                goto frame_err;
        }
 
@@ -2591,6 +2595,8 @@ static void virtnet_receive_done(struct virtnet_info *vi, 
struct receive_queue *
                goto frame_err;
        }
 
+       virtio_net_out_net_header_to_skb(skb, &hdr->out_net_hdr, 
vi->out_net_hdr_negotiated,
+                                        virtio_is_little_endian(vi->vdev));
        skb_record_rx_queue(skb, vq2rxq(rq->vq));
        skb->protocol = eth_type_trans(skb, dev);
        pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
@@ -3317,6 +3323,9 @@ static int xmit_skb(struct send_queue *sq, struct sk_buff 
*skb, bool orphan)
        else
                hdr = &skb_vnet_common_hdr(skb)->tnl_hdr;
 
+       virtio_net_out_net_header_from_skb(skb, 
&skb_vnet_common_hdr(skb)->out_net_hdr,
+                                          vi->out_net_hdr_negotiated,
+                                          virtio_is_little_endian(vi->vdev));
        if (virtio_net_hdr_tnl_from_skb(skb, hdr, vi->tx_tnl,
                                        virtio_is_little_endian(vi->vdev), 0))
                return -EPROTO;
@@ -6915,8 +6924,10 @@ static int virtnet_probe(struct virtio_device *vdev)
                dev->xdp_metadata_ops = &virtnet_xdp_metadata_ops;
        }
 
-       if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UDP_TUNNEL_GSO) ||
-           virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UDP_TUNNEL_GSO))
+       if (virtio_has_feature(vdev, VIRTIO_NET_F_OUT_NET_HEADER))
+               vi->hdr_len = sizeof(struct 
virtio_net_hdr_v1_hash_tunnel_out_net_hdr);
+       else if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UDP_TUNNEL_GSO) ||
+                virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UDP_TUNNEL_GSO))
                vi->hdr_len = sizeof(struct virtio_net_hdr_v1_hash_tunnel);
        else if (vi->has_rss_hash_report)
                vi->hdr_len = sizeof(struct virtio_net_hdr_v1_hash);
@@ -6933,6 +6944,9 @@ static int virtnet_probe(struct virtio_device *vdev)
        if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UDP_TUNNEL_GSO))
                vi->tx_tnl = true;
 
+       if (virtio_has_feature(vdev, VIRTIO_NET_F_OUT_NET_HEADER))
+               vi->out_net_hdr_negotiated = true;
+
        if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
            virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
                vi->any_header_sg = true;
@@ -7247,6 +7261,7 @@ static unsigned int features[] = {
        VIRTIO_NET_F_GUEST_UDP_TUNNEL_GSO_CSUM,
        VIRTIO_NET_F_HOST_UDP_TUNNEL_GSO,
        VIRTIO_NET_F_HOST_UDP_TUNNEL_GSO_CSUM,
+       VIRTIO_NET_F_OUT_NET_HEADER,
 };
 
 static unsigned int features_legacy[] = {
-- 
2.48.1