Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751832AbZKPBSR (ORCPT ); Sun, 15 Nov 2009 20:18:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751156AbZKPBSQ (ORCPT ); Sun, 15 Nov 2009 20:18:16 -0500 Received: from mail-yx0-f187.google.com ([209.85.210.187]:45524 "EHLO mail-yx0-f187.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751329AbZKPBSP (ORCPT ); Sun, 15 Nov 2009 20:18:15 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :content-type; b=r/isYboyD+IvPVu2KKlbzO8GRj8SXLqNVbbJKFCGouYE05ffkwLD/mGtZEDNODbx26 kB+b5553yUGthKQVF4eVYyQPK1AXfrIorDjtnREehb+u/vzlnIMjiR7uNpSU17h4Z9qe Kg8QeodIRWRXEEXr0NUWlCjL4dhj6HduIgGsI= Message-ID: <4B00A858.8000705@gmail.com> Date: Sun, 15 Nov 2009 20:18:16 -0500 From: William Allen Simpson User-Agent: Thunderbird 2.0.0.23 (Macintosh/20090812) MIME-Version: 1.0 To: Linux Kernel Network Developers CC: Linux Kernel Developers , David Miller Subject: [PATCH v1 resent] net: TCP_MSS_DEFAULT, TCP_MSS_DESIRED Content-Type: multipart/mixed; boundary="------------000801080008050209040204" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5398 Lines: 154 This is a multi-part message in MIME format. --------------000801080008050209040204 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Define two symbols needed in both kernel and user space. Remove old (somewhat incorrect) kernel variant that wasn't used in most cases. Default should apply to both RMSS and SMSS (RFC2581). Replace numeric constants with defined symbols. Stand-alone patch, originally developed for TCPCT. Signed-off-by: William.Allen.Simpson@gmail.com Acked-by: Eric Dumazet --- include/linux/tcp.h | 6 ++++++ include/net/tcp.h | 3 --- net/ipv4/tcp_input.c | 4 ++-- net/ipv4/tcp_ipv4.c | 6 +++--- net/ipv4/tcp_minisocks.c | 2 +- net/ipv6/tcp_ipv6.c | 2 +- 6 files changed, 13 insertions(+), 10 deletions(-) --------------000801080008050209040204 Content-Type: text/plain; x-mac-type="54455854"; x-mac-creator="0"; name="TCP_MSSv1.patch" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="TCP_MSSv1.patch" diff --git a/include/linux/tcp.h b/include/linux/tcp.h index eeecb85..32d7d77 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -81,6 +81,12 @@ enum { TCP_DATA_OFFSET = __cpu_to_be32(0xF0000000) }; +/* + * TCP general constants + */ +#define TCP_MSS_DEFAULT 536U /* IPv4 (RFC1122, RFC2581) */ +#define TCP_MSS_DESIRED 1220U /* IPv6 (tunneled), EDNS0 (RFC3226) */ + /* TCP socket options */ #define TCP_NODELAY 1 /* Turn off Nagle's algorithm. */ #define TCP_MAXSEG 2 /* Limit MSS */ diff --git a/include/net/tcp.h b/include/net/tcp.h index 25bf3ba..a413e9f 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -62,9 +62,6 @@ extern void tcp_time_wait(struct sock *sk, int state, int timeo); /* Minimal accepted MSS. It is (60+60+8) - (20+20). */ #define TCP_MIN_MSS 88U -/* Minimal RCV_MSS. */ -#define TCP_MIN_RCVMSS 536U - /* The least MTU to use for probing */ #define TCP_BASE_MSS 512 diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index be0c5bf..cc306ac 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -140,7 +140,7 @@ static void tcp_measure_rcv_mss(struct sock *sk, const struct sk_buff *skb) * "len" is invariant segment length, including TCP header. */ len += skb->data - skb_transport_header(skb); - if (len >= TCP_MIN_RCVMSS + sizeof(struct tcphdr) || + if (len >= TCP_MSS_DEFAULT + sizeof(struct tcphdr) || /* If PSH is not set, packet should be * full sized, provided peer TCP is not badly broken. * This observation (if it is correct 8)) allows @@ -411,7 +411,7 @@ void tcp_initialize_rcv_mss(struct sock *sk) unsigned int hint = min_t(unsigned int, tp->advmss, tp->mss_cache); hint = min(hint, tp->rcv_wnd / 2); - hint = min(hint, TCP_MIN_RCVMSS); + hint = min(hint, TCP_MSS_DEFAULT); hint = max(hint, TCP_MIN_MSS); inet_csk(sk)->icsk_ack.rcv_mss = hint; diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index f83ac91..0718fde 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -217,7 +217,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) if (inet->opt) inet_csk(sk)->icsk_ext_hdr_len = inet->opt->optlen; - tp->rx_opt.mss_clamp = 536; + tp->rx_opt.mss_clamp = TCP_MSS_DEFAULT; /* Socket identity is still unknown (sport may be zero). * However we set state to SYN-SENT and not releasing socket @@ -1270,7 +1270,7 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) goto drop_and_free; tcp_clear_options(&tmp_opt); - tmp_opt.mss_clamp = 536; + tmp_opt.mss_clamp = TCP_MSS_DEFAULT; tmp_opt.user_mss = tcp_sk(sk)->rx_opt.user_mss; tcp_parse_options(skb, &tmp_opt, 0, dst); @@ -1818,7 +1818,7 @@ static int tcp_v4_init_sock(struct sock *sk) */ tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; tp->snd_cwnd_clamp = ~0; - tp->mss_cache = 536; + tp->mss_cache = TCP_MSS_DEFAULT; tp->reordering = sysctl_tcp_reordering; icsk->icsk_ca_ops = &tcp_init_congestion_ops; diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index fb68bab..7a42990 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -476,7 +476,7 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req, if (newtp->af_specific->md5_lookup(sk, newsk)) newtp->tcp_header_len += TCPOLEN_MD5SIG_ALIGNED; #endif - if (skb->len >= TCP_MIN_RCVMSS+newtp->tcp_header_len) + if (skb->len >= TCP_MSS_DEFAULT + newtp->tcp_header_len) newicsk->icsk_ack.last_seg_size = skb->len - newtp->tcp_header_len; newtp->rx_opt.mss_clamp = req->mss; TCP_ECN_openreq_child(newtp, req); diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 6951827..b528f75 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1849,7 +1849,7 @@ static int tcp_v6_init_sock(struct sock *sk) */ tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; tp->snd_cwnd_clamp = ~0; - tp->mss_cache = 536; + tp->mss_cache = TCP_MSS_DEFAULT; tp->reordering = sysctl_tcp_reordering; -- 1.6.3.3 --------------000801080008050209040204-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/