From f2fb4ab2a647d6576812cbb3ae1979538112f6c8 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Tue, 13 Nov 2012 01:13:38 +0000 Subject: [PATCH] igb: Do not parse past IP header on fragments beyond the first This change makes it so that only the first fragment in a series of fragments will have the L4 header pulled. Previously we were always pulling the L4 header as well and in the case of UDP this can harm performance since only the first fragment will have the header, the rest just contain data which should be left in the paged portion of the packet. Signed-off-by: Alexander Duyck Tested-by: Aaron Brown Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/igb/igb_main.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index 0fe25210629b..0ce145e93545 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -6145,20 +6145,23 @@ static unsigned int igb_get_headlen(unsigned char *data, if (hlen < sizeof(struct iphdr)) return hdr.network - data; - /* record next protocol */ - nexthdr = hdr.ipv4->protocol; - hdr.network += hlen; + /* record next protocol if header is present */ + if (!hdr.ipv4->frag_off) + nexthdr = hdr.ipv4->protocol; } else if (protocol == __constant_htons(ETH_P_IPV6)) { if ((hdr.network - data) > (max_len - sizeof(struct ipv6hdr))) return max_len; /* record next protocol */ nexthdr = hdr.ipv6->nexthdr; - hdr.network += sizeof(struct ipv6hdr); + hlen = sizeof(struct ipv6hdr); } else { return hdr.network - data; } + /* relocate pointer to start of L4 header */ + hdr.network += hlen; + /* finally sort out TCP */ if (nexthdr == IPPROTO_TCP) { if ((hdr.network - data) > (max_len - sizeof(struct tcphdr))) -- 2.20.1