From patchwork Wed Oct 18 14:30:00 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ursula Braun X-Patchwork-Id: 827632 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3yHDx65Bc5z9t5s for ; Thu, 19 Oct 2017 01:30:18 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751949AbdJROaR (ORCPT ); Wed, 18 Oct 2017 10:30:17 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:51484 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751108AbdJROaM (ORCPT ); Wed, 18 Oct 2017 10:30:12 -0400 Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v9IETKUm044523 for ; Wed, 18 Oct 2017 10:30:11 -0400 Received: from e06smtp10.uk.ibm.com (e06smtp10.uk.ibm.com [195.75.94.106]) by mx0b-001b2d01.pphosted.com with ESMTP id 2dp4ukhd2u-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Wed, 18 Oct 2017 10:30:11 -0400 Received: from localhost by e06smtp10.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Wed, 18 Oct 2017 15:30:07 +0100 Received: from d06av21.portsmouth.uk.ibm.com (d06av21.portsmouth.uk.ibm.com [9.149.105.232]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v9IEU7mm20971534; Wed, 18 Oct 2017 14:30:07 GMT Received: from d06av21.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B9D7852041; Wed, 18 Oct 2017 14:24:26 +0100 (BST) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by d06av21.portsmouth.uk.ibm.com (Postfix) with ESMTPS id 785FB52047; Wed, 18 Oct 2017 14:24:26 +0100 (BST) From: Ursula Braun To: davem@davemloft.net Cc: netdev@vger.kernel.org, linux-s390@vger.kernel.org, jwi@linux.vnet.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, raspl@linux.vnet.ibm.com, ubraun@linux.vnet.ibm.com Subject: [PATCH V2 net-next 3/3] smc: add SMC rendezvous protocol Date: Wed, 18 Oct 2017 16:30:00 +0200 X-Mailer: git-send-email 2.13.5 In-Reply-To: <20171018143000.23884-1-ubraun@linux.vnet.ibm.com> References: <20171018143000.23884-1-ubraun@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 17101814-0040-0000-0000-000003E40C30 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17101814-0041-0000-0000-000025E65C29 Message-Id: <20171018143000.23884-4-ubraun@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-10-18_06:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=4 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1707230000 definitions=main-1710180203 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The SMC protocol [1] uses a rendezvous protocol to negotiate SMC capability between peers. The current Linux implementation does not yet use this rendezvous protocol and, thus, is not compliant to RFC7609 and incompatible with other SMC implementations like in zOS. This patch adds support for the SMC rendezvous protocol. It uses a new TCP experimental option. With this option, SMC capabilities are exchanged between the peers during the TCP three way handshake. [1] SMC-R Informational RFC: http://www.rfc-editor.org/info/rfc7609 Signed-off-by: Ursula Braun --- net/smc/af_smc.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 70f7640f5090..6451c5013e06 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -390,6 +390,12 @@ static int smc_connect_rdma(struct smc_sock *smc) int rc = 0; u8 ibport; + if (!tcp_sk(smc->clcsock->sk)->syn_smc) { + /* peer has not signalled SMC-capability */ + smc->use_fallback = true; + goto out_connected; + } + /* IPSec connections opt out of SMC-R optimizations */ if (using_ipsec(smc)) { reason_code = SMC_CLC_DECL_IPSEC; @@ -555,6 +561,7 @@ static int smc_connect(struct socket *sock, struct sockaddr *addr, } smc_copy_sock_settings_to_clc(smc); + tcp_sk(smc->clcsock->sk)->syn_smc = 1; rc = kernel_connect(smc->clcsock, addr, alen, flags); if (rc) goto out; @@ -759,6 +766,12 @@ static void smc_listen_work(struct work_struct *work) u8 prefix_len; u8 ibport; + /* check if peer is smc capable */ + if (!tcp_sk(newclcsock->sk)->syn_smc) { + new_smc->use_fallback = true; + goto out_connected; + } + /* do inband token exchange - *wait for and receive SMC Proposal CLC message */ @@ -967,6 +980,7 @@ static int smc_listen(struct socket *sock, int backlog) * them to the clc socket -- copy smc socket options to clc socket */ smc_copy_sock_settings_to_clc(smc); + tcp_sk(smc->clcsock->sk)->syn_smc = 1; rc = kernel_listen(smc->clcsock, backlog); if (rc) @@ -1409,6 +1423,7 @@ static int __init smc_init(void) goto out_sock; } + static_branch_enable(&tcp_have_smc); return 0; out_sock: @@ -1433,6 +1448,7 @@ static void __exit smc_exit(void) list_del_init(&lgr->list); smc_lgr_free(lgr); /* free link group */ } + static_branch_disable(&tcp_have_smc); smc_ib_unregister_client(); sock_unregister(PF_SMC); proto_unregister(&smc_proto);