From: "J. Bruce Fields" Subject: Re: [PATCH 05/29] nfsd41: create_session cache hold client reference Date: Thu, 23 Apr 2009 19:28:25 -0400 Message-ID: <20090423232825.GK1906@fieldses.org> References: <1240504988-9572-1-git-send-email-andros@netapp.com> <1240504988-9572-2-git-send-email-andros@netapp.com> <1240504988-9572-3-git-send-email-andros@netapp.com> <1240504988-9572-4-git-send-email-andros@netapp.com> <1240504988-9572-5-git-send-email-andros@netapp.com> <1240504988-9572-6-git-send-email-andros@netapp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-nfs@vger.kernel.org, pnfs@linux-nfs.org To: andros@netapp.com Return-path: Received: from mail.fieldses.org ([141.211.133.115]:50897 "EHLO pickle.fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752590AbZDWX2Z (ORCPT ); Thu, 23 Apr 2009 19:28:25 -0400 In-Reply-To: <1240504988-9572-6-git-send-email-andros@netapp.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Thu, Apr 23, 2009 at 12:42:44PM -0400, andros@netapp.com wrote: > From: Andy Adamson > > expire_client can be called on a confirmed or unconfirmed client while > processing the create session operation and accessing the clientid slot. I don't understand--isn't all that under the state lock for now? --b. > > Signed-off-by: Andy Adamson > --- > fs/nfsd/nfs4state.c | 14 ++++++++++---- > 1 files changed, 10 insertions(+), 4 deletions(-) > > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > index a585a58..accad58 100644 > --- a/fs/nfsd/nfs4state.c > +++ b/fs/nfsd/nfs4state.c > @@ -1355,6 +1355,7 @@ nfsd4_create_session(struct svc_rqst *rqstp, > conf = find_confirmed_client(&cr_ses->clientid); > > if (conf) { > + atomic_inc(&conf->cl_count); > slot = &conf->cl_slot; > status = check_slot_seqid(cr_ses->seqid, slot); > if (status == nfserr_replay_cache) { > @@ -1363,27 +1364,30 @@ nfsd4_create_session(struct svc_rqst *rqstp, > cstate->status = nfserr_replay_clientid_cache; > /* Return the cached reply status */ > status = nfsd4_replay_create_session(resp, slot); > - goto out; > + goto out_put; > } else if (cr_ses->seqid != conf->cl_slot.sl_seqid + 1) { > status = nfserr_seq_misordered; > dprintk("Sequence misordered!\n"); > dprintk("Expected seqid= %d but got seqid= %d\n", > slot->sl_seqid, cr_ses->seqid); > - goto out; > + goto out_put; > } > conf->cl_slot.sl_seqid++; > } else if (unconf) { > + atomic_inc(&unconf->cl_count); > slot = &unconf->cl_slot; > status = check_slot_seqid(cr_ses->seqid, slot); > if (status) { > /* an unconfirmed replay returns misordered */ > status = nfserr_seq_misordered; > - goto out; > + conf = unconf; /* for put_nfs4_client */ > + goto out_put; > } > > if (!same_creds(&unconf->cl_cred, &rqstp->rq_cred) || > (ip_addr != unconf->cl_addr)) { > status = nfserr_clid_inuse; > + conf = unconf; /* for put_nfs4_client */ > goto out_cache; > } > > @@ -1413,7 +1417,7 @@ nfsd4_create_session(struct svc_rqst *rqstp, > > status = alloc_init_session(rqstp, conf, cr_ses); > if (status) > - goto out; > + goto out_put; > > memcpy(cr_ses->sessionid.data, conf->cl_sessionid.data, > NFS4_MAX_SESSIONID_LEN); > @@ -1423,6 +1427,8 @@ out_cache: > /* cache solo and embedded create sessions under the state lock */ > nfsd4_cache_create_session(cr_ses, slot, status); > > +out_put: > + put_nfs4_client(conf); > out: > nfs4_unlock_state(); > dprintk("%s returns %d\n", __func__, ntohl(status)); > -- > 1.5.4.3 >