From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gilad Ben-Yossef Subject: [PATCH v3 4/7] Add the no SACK route option feature Date: Mon, 26 Oct 2009 10:06:30 +0200 Message-ID: <1256544393-12450-5-git-send-email-gilad@codefidence.com> References: <1256544393-12450-1-git-send-email-gilad@codefidence.com> Cc: ori@comsleep.com, Gilad Ben-Yossef To: netdev@vger.kernel.org Return-path: Received: from xenbox.codefidence.com ([92.48.73.16]:47189 "EHLO xenbox.codefidence.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755210AbZJZIGj (ORCPT ); Mon, 26 Oct 2009 04:06:39 -0400 In-Reply-To: <1256544393-12450-1-git-send-email-gilad@codefidence.com> Sender: netdev-owner@vger.kernel.org List-ID: Implement querying and acting upon the no sack bit in the features field. Signed-off-by: Gilad Ben-Yossef Sigend-off-by: Ori Finkelman Sigend-off-by: Yony Amit --- include/linux/rtnetlink.h | 2 +- net/ipv4/tcp_input.c | 3 ++- net/ipv4/tcp_output.c | 4 +++- 3 files changed, 6 insertions(+), 3 deletions(-) diff --git a/include/linux/rtnetlink.h b/include/linux/rtnetlink.h index adf2068..9c802a6 100644 --- a/include/linux/rtnetlink.h +++ b/include/linux/rtnetlink.h @@ -377,7 +377,7 @@ enum #define RTAX_MAX (__RTAX_MAX - 1) #define RTAX_FEATURE_ECN 0x00000001 -#define RTAX_FEATURE_SACK 0x00000002 +#define RTAX_FEATURE_NO_SACK 0x00000002 #define RTAX_FEATURE_TIMESTAMP 0x00000004 #define RTAX_FEATURE_ALLFRAG 0x00000008 diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index d502f49..b14f780 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3763,7 +3763,8 @@ void tcp_parse_options(struct sk_buff *skb, struct tcp_options_received *opt_rx, break; case TCPOPT_SACK_PERM: if (opsize == TCPOLEN_SACK_PERM && th->syn && - !estab && sysctl_tcp_sack) { + !estab && sysctl_tcp_sack && + !dst_feature(dst, RTAX_FEATURE_NO_SACK)) { opt_rx->sack_ok = 1; tcp_sack_reset(opt_rx); } diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index fcd278a..64db8dd 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -464,6 +464,7 @@ static unsigned tcp_syn_options(struct sock *sk, struct sk_buff *skb, struct tcp_md5sig_key **md5) { struct tcp_sock *tp = tcp_sk(sk); unsigned size = 0; + struct dst_entry *dst = __sk_dst_get(sk); #ifdef CONFIG_TCP_MD5SIG *md5 = tp->af_specific->md5_lookup(sk, sk); @@ -498,7 +499,8 @@ static unsigned tcp_syn_options(struct sock *sk, struct sk_buff *skb, opts->options |= OPTION_WSCALE; size += TCPOLEN_WSCALE_ALIGNED; } - if (likely(sysctl_tcp_sack)) { + if (likely(sysctl_tcp_sack && + !dst_feature(dst, RTAX_FEATURE_NO_SACK))) { opts->options |= OPTION_SACK_ADVERTISE; if (unlikely(!(OPTION_TS & opts->options))) size += TCPOLEN_SACKPERM_ALIGNED; -- 1.5.6.3