From 493c6be3fedfe24aa676949b237b9b104d911abf Mon Sep 17 00:00:00 2001 From: Sridhar Samudrala Date: Thu, 9 Jul 2009 08:09:54 +0000 Subject: [PATCH] udpv6: Fix HW checksum support for outgoing UFO packets - add HW checksum support for outgoing large UDP/IPv6 packets destined for a UFO enabled device. Signed-off-by: Sridhar Samudrala Acked-by: Herbert Xu Signed-off-by: David S. Miller --- net/ipv6/udp.c | 48 +++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 47 insertions(+), 1 deletion(-) diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 33b59bd92c4d..f31b1b9b0e0e 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -638,6 +638,47 @@ static void udp_v6_flush_pending_frames(struct sock *sk) } } +/** + * udp6_hwcsum_outgoing - handle outgoing HW checksumming + * @sk: socket we are sending on + * @skb: sk_buff containing the filled-in UDP header + * (checksum field must be zeroed out) + */ +static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb, + const struct in6_addr *saddr, + const struct in6_addr *daddr, int len) +{ + unsigned int offset; + struct udphdr *uh = udp_hdr(skb); + __wsum csum = 0; + + if (skb_queue_len(&sk->sk_write_queue) == 1) { + /* Only one fragment on the socket. */ + skb->csum_start = skb_transport_header(skb) - skb->head; + skb->csum_offset = offsetof(struct udphdr, check); + uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0); + } else { + /* + * HW-checksum won't work as there are two or more + * fragments on the socket so that all csums of sk_buffs + * should be together + */ + offset = skb_transport_offset(skb); + skb->csum = skb_checksum(skb, offset, skb->len - offset, 0); + + skb->ip_summed = CHECKSUM_NONE; + + skb_queue_walk(&sk->sk_write_queue, skb) { + csum = csum_add(csum, skb->csum); + } + + uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, + csum); + if (uh->check == 0) + uh->check = CSUM_MANGLED_0; + } +} + /* * Sending */ @@ -668,7 +709,11 @@ static int udp_v6_push_pending_frames(struct sock *sk) if (is_udplite) csum = udplite_csum_outgoing(sk, skb); - else + else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */ + udp6_hwcsum_outgoing(sk, skb, &fl->fl6_src, &fl->fl6_dst, + up->len); + goto send; + } else csum = udp_csum_outgoing(sk, skb); /* add protocol-dependent pseudo-header */ @@ -677,6 +722,7 @@ static int udp_v6_push_pending_frames(struct sock *sk) if (uh->check == 0) uh->check = CSUM_MANGLED_0; +send: err = ip6_push_pending_frames(sk); out: up->len = 0; -- 2.30.2