From 36707061d6bafc254b3dfc23a8bb95451812b233 Mon Sep 17 00:00:00 2001 From: Alexander Lobakin Date: Fri, 22 Jan 2021 18:20:02 +0000 Subject: [PATCH] udp: allow forwarding of plain (non-fraglisted) UDP GRO packets Commit 9fd1ff5d2ac7 ("udp: Support UDP fraglist GRO/GSO.") actually not only added a support for fraglisted UDP GRO, but also tweaked some logics the way that non-fraglisted UDP GRO started to work for forwarding too. Commit 2e4ef10f5850 ("net: add GSO UDP L4 and GSO fraglists to the list of software-backed types") added GSO UDP L4 to the list of software GSO to allow virtual netdevs to forward them as is up to the real drivers. Tests showed that currently forwarding and NATing of plain UDP GRO packets are performed fully correctly, regardless if the target netdevice has a support for hardware/driver GSO UDP L4 or not. Add the last element and allow to form plain UDP GRO packets if we are on forwarding path, and the new NETIF_F_GRO_UDP_FWD is enabled on a receiving netdevice. If both NETIF_F_GRO_FRAGLIST and NETIF_F_GRO_UDP_FWD are set, fraglisted GRO takes precedence. This keeps the current behaviour and is generally more optimal for now, as the number of NICs with hardware USO offload is relatively small. Signed-off-by: Alexander Lobakin Acked-by: Willem de Bruijn Signed-off-by: Jakub Kicinski --- net/ipv4/udp_offload.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c index 1168d186cc43..41249705d9e9 100644 --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -460,7 +460,8 @@ struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb, if (skb->dev->features & NETIF_F_GRO_FRAGLIST) NAPI_GRO_CB(skb)->is_flist = sk ? !udp_sk(sk)->gro_enabled: 1; - if ((sk && udp_sk(sk)->gro_enabled) || NAPI_GRO_CB(skb)->is_flist) { + if ((!sk && (skb->dev->features & NETIF_F_GRO_UDP_FWD)) || + (sk && udp_sk(sk)->gro_enabled) || NAPI_GRO_CB(skb)->is_flist) { pp = call_gro_receive(udp_gro_receive_segment, head, skb); return pp; }