diff options
| author | Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> | 2008-11-24 21:13:50 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2008-11-24 21:13:50 -0800 |
| commit | adb92db857ee2a0a2b925ccfbd560203c3f88aae (patch) | |
| tree | fac842e439d3a6bcd54aef5ab72a53fa831119a9 | |
| parent | e8bae275d9354104f7ae24a48a90d1a6286e7bd9 (diff) | |
| download | blackbird-op-linux-adb92db857ee2a0a2b925ccfbd560203c3f88aae.tar.gz blackbird-op-linux-adb92db857ee2a0a2b925ccfbd560203c3f88aae.zip | |
tcp: Make SACK code to split only at mss boundaries
Sadly enough, this adds possible divide though we try to avoid
it by checking one mss as common case.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv4/tcp_input.c | 27 |
1 files changed, 23 insertions, 4 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 3f26599ddc88..ca46eb9151f8 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1248,20 +1248,39 @@ static int tcp_match_skb_to_sack(struct sock *sk, struct sk_buff *skb, { int in_sack, err; unsigned int pkt_len; + unsigned int mss; in_sack = !after(start_seq, TCP_SKB_CB(skb)->seq) && !before(end_seq, TCP_SKB_CB(skb)->end_seq); if (tcp_skb_pcount(skb) > 1 && !in_sack && after(TCP_SKB_CB(skb)->end_seq, start_seq)) { - + mss = tcp_skb_mss(skb); in_sack = !after(start_seq, TCP_SKB_CB(skb)->seq); - if (!in_sack) + if (!in_sack) { pkt_len = start_seq - TCP_SKB_CB(skb)->seq; - else + if (pkt_len < mss) + pkt_len = mss; + } else { pkt_len = end_seq - TCP_SKB_CB(skb)->seq; - err = tcp_fragment(sk, skb, pkt_len, skb_shinfo(skb)->gso_size); + if (pkt_len < mss) + return -EINVAL; + } + + /* Round if necessary so that SACKs cover only full MSSes + * and/or the remaining small portion (if present) + */ + if (pkt_len > mss) { + unsigned int new_len = (pkt_len / mss) * mss; + if (!in_sack && new_len < pkt_len) { + new_len += mss; + if (new_len > skb->len) + return 0; + } + pkt_len = new_len; + } + err = tcp_fragment(sk, skb, pkt_len, mss); if (err < 0) return err; } |
