From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 68255C3F2C6 for ; Tue, 3 Mar 2020 15:57:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 44A2F208C3 for ; Tue, 3 Mar 2020 15:57:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730055AbgCCP5N (ORCPT ); Tue, 3 Mar 2020 10:57:13 -0500 Received: from fieldses.org ([173.255.197.46]:37232 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729553AbgCCP5N (ORCPT ); Tue, 3 Mar 2020 10:57:13 -0500 Received: by fieldses.org (Postfix, from userid 2815) id 4CB3F1C17; Tue, 3 Mar 2020 10:57:13 -0500 (EST) Date: Tue, 3 Mar 2020 10:57:13 -0500 From: "J. Bruce Fields" To: Scott Mayhew Cc: chuck.lever@oracle.com, linux-nfs@vger.kernel.org Subject: Re: [PATCH] nfsd: set the server_scope during service startup Message-ID: <20200303155713.GE17257@fieldses.org> References: <20200219205215.3429408-1-smayhew@redhat.com> <20200219213230.GC23275@fieldses.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200219213230.GC23275@fieldses.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org On Wed, Feb 19, 2020 at 04:32:30PM -0500, J. Bruce Fields wrote: > On Wed, Feb 19, 2020 at 03:52:15PM -0500, Scott Mayhew wrote: > > Currently, nfsd4_encode_exchange_id() encodes the utsname nodename > > string in the server_scope field. In a multi-host container > > environemnt, if an nfsd container is restarted on a different host than > > it was originally running on, clients will see a server_scope mismatch > > and will not attempt to reclaim opens. > > > > Instead, set the server_scope while we're in a process context during > > service startup, so we get the utsname nodename of the current process > > and store that in nfsd_net. > > Thanks! Just one nit: > > > Signed-off-by: Scott Mayhew > > --- > > fs/nfsd/netns.h | 1 + > > fs/nfsd/nfs4xdr.c | 3 ++- > > fs/nfsd/nfssvc.c | 3 +++ > > 3 files changed, 6 insertions(+), 1 deletion(-) > > > > diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h > > index 2baf32311e00..c6d95700105e 100644 > > --- a/fs/nfsd/netns.h > > +++ b/fs/nfsd/netns.h > > @@ -172,6 +172,7 @@ struct nfsd_net { > > unsigned int longest_chain_cachesize; > > > > struct shrinker nfsd_reply_cache_shrinker; > > + char server_scope[UNX_MAXNODENAME+1]; > > }; > > > > /* Simple check to find out if a given net was properly initialized */ > > diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c > > index 9761512674a0..209174ee431a 100644 > > --- a/fs/nfsd/nfs4xdr.c > > +++ b/fs/nfsd/nfs4xdr.c > > @@ -4005,10 +4005,11 @@ nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr, > > int major_id_sz; > > int server_scope_sz; > > uint64_t minor_id = 0; > > + struct nfsd_net *nn = net_generic(SVC_NET(resp->rqstp), nfsd_net_id); > > > > major_id = utsname()->nodename; > > major_id_sz = strlen(major_id); > > We should do this one too. I'll fix that up and apply if that's OK. And then maybe "server_scope" isn't the best name for the variable any more. Applying as below if you don't see any objection.--b. commit 9eb54e92718a Author: Scott Mayhew Date: Wed Feb 19 15:52:15 2020 -0500 nfsd: set the server_scope during service startup Currently, nfsd4_encode_exchange_id() encodes the utsname nodename string in the server_scope field. In a multi-host container environemnt, if an nfsd container is restarted on a different host than it was originally running on, clients will see a server_scope mismatch and will not attempt to reclaim opens. Instead, set the server_scope while we're in a process context during service startup, so we get the utsname nodename of the current process and store that in nfsd_net. Signed-off-by: Scott Mayhew [bfields: fix up major_id too] Signed-off-by: J. Bruce Fields diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h index 2baf32311e00..09aa545825bd 100644 --- a/fs/nfsd/netns.h +++ b/fs/nfsd/netns.h @@ -172,6 +172,8 @@ struct nfsd_net { unsigned int longest_chain_cachesize; struct shrinker nfsd_reply_cache_shrinker; + /* utsname taken from the the process that starts the server */ + char nfsd_name[UNX_MAXNODENAME+1]; }; /* Simple check to find out if a given net was properly initialized */ diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 9761512674a0..ad38aed6f5c2 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -4005,11 +4005,12 @@ nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr, int major_id_sz; int server_scope_sz; uint64_t minor_id = 0; + struct nfsd_net *nn = net_generic(SVC_NET(resp->rqstp), nfsd_net_id); - major_id = utsname()->nodename; - major_id_sz = strlen(major_id); - server_scope = utsname()->nodename; - server_scope_sz = strlen(server_scope); + major_id = nn->nfsd_name; + major_id_sz = strlen(nn->nfsd_name); + server_scope = nn->nfsd_name; + server_scope_sz = strlen(nn->nfsd_name); p = xdr_reserve_space(xdr, 8 /* eir_clientid */ + diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index 3b77b904212d..ca9fd348548b 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -749,6 +749,9 @@ nfsd_svc(int nrservs, struct net *net, const struct cred *cred) if (nrservs == 0 && nn->nfsd_serv == NULL) goto out; + strlcpy(nn->nfsd_name, utsname()->nodename, + sizeof(nn->nfsd_name)); + error = nfsd_create_serv(net); if (error) goto out;