From 32dce968dd987adfb0c00946d78dad9154f64759 Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Sat, 31 Jan 2015 10:40:18 -0500 Subject: [PATCH] ipv6: Allow for partial checksums on non-ufo packets Currntly, if we are not doing UFO on the packet, all UDP packets will start with CHECKSUM_NONE and thus perform full checksum computations in software even if device support IPv6 checksum offloading. Let's start start with CHECKSUM_PARTIAL if the device supports it and we are sending only a single packet at or below mtu size. Signed-off-by: Vladislav Yasevich Signed-off-by: David S. Miller --- net/ipv6/ip6_output.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index b89d3c27dac7a..1a036f35d833e 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -1227,6 +1227,7 @@ static int __ip6_append_data(struct sock *sk, u32 tskey = 0; struct rt6_info *rt = (struct rt6_info *)cork->dst; struct ipv6_txoptions *opt = v6_cork->opt; + int csummode = CHECKSUM_NONE; skb = skb_peek_tail(queue); if (!skb) { @@ -1283,6 +1284,14 @@ static int __ip6_append_data(struct sock *sk, tskey = sk->sk_tskey++; } + /* If this is the first and only packet and device + * supports checksum offloading, let's use it. + */ + if (!skb && + length + fragheaderlen < mtu && + rt->dst.dev->features & NETIF_F_V6_CSUM && + !exthdrlen) + csummode = CHECKSUM_PARTIAL; /* * Let's try using as much space as possible. * Use MTU if total length of the message fits into the MTU. @@ -1395,7 +1404,7 @@ static int __ip6_append_data(struct sock *sk, * Fill in the control structures */ skb->protocol = htons(ETH_P_IPV6); - skb->ip_summed = CHECKSUM_NONE; + skb->ip_summed = csummode; skb->csum = 0; /* reserve for fragmentation and ipsec header */ skb_reserve(skb, hh_len + sizeof(struct frag_hdr) +