udp: add support for UDP_GRO cmsg
When UDP GRO is enabled, the UDP_GRO cmsg will carry the ingress
datagram size. User-space can use such info to compute the original
packets layout.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/udp.h b/include/linux/udp.h
index f613b32..e23d502 100644
--- a/include/linux/udp.h
+++ b/include/linux/udp.h
@@ -121,6 +121,17 @@
return udp_sk(sk)->no_check6_rx;
}
+static inline void udp_cmsg_recv(struct msghdr *msg, struct sock *sk,
+ struct sk_buff *skb)
+{
+ int gso_size;
+
+ if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) {
+ gso_size = skb_shinfo(skb)->gso_size;
+ put_cmsg(msg, SOL_UDP, UDP_GRO, sizeof(gso_size), &gso_size);
+ }
+}
+
#define udp_portaddr_for_each_entry(__sk, list) \
hlist_for_each_entry(__sk, list, __sk_common.skc_portaddr_node)