Return-Path: Received: from cn.fujitsu.com ([222.73.24.84]:64102 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1752700Ab0IHDLX (ORCPT ); Tue, 7 Sep 2010 23:11:23 -0400 Message-ID: <4C86FECF.2050103@cn.fujitsu.com> Date: Wed, 08 Sep 2010 11:11:11 +0800 From: Bian Naimeng To: Trond Myklebust CC: linux-nfs@vger.kernel.org, "J. Bruce Fields" Subject: Re: [PATCH 2/2] We should clear NFS_DELEGATED_STATE after return delegation References: <4C592F85.8070308@cn.fujitsu.com> <4C59306A.9090302@cn.fujitsu.com> <1280925913.3011.23.camel@heimdal.trondhjem.org> <4C5A213F.9000506@cn.fujitsu.com> <1281013423.2948.1.camel@heimdal.trondhjem.org> <4C5B8B48.4050008@cn.fujitsu.com> <1281101448.3586.11.camel@heimdal.trondhjem.org> <4C68EDAE.5000201@cn.fujitsu.com> <1282087012.18385.30.camel@heimdal.trondhjem.org> <4C7DF56B.3040206@cn.fujitsu.com> <1283897068.9097.15.camel@heimdal.trondhjem.org> <4C86E7FA.7020701@cn.fujitsu.com> <1283911036.16070.1.camel@heimdal.trondhjem.org> In-Reply-To: <1283911036.16070.1.camel@heimdal.trondhjem.org> Content-Type: text/plain; charset=UTF-8 Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 If there are not any delegation at this inode, we should clear stateid's NFS_DELEGATED_STATE when update it. Signed-off-by: Bian Naimeng --- fs/nfs/delegation.c | 1 + fs/nfs/nfs4proc.c | 12 +++++++++++- 2 files changed, 12 insertions(+), 1 deletions(-) diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c index b9c3c43..62f296e 100644 --- a/fs/nfs/delegation.c +++ b/fs/nfs/delegation.c @@ -106,6 +106,7 @@ again: continue; if (memcmp(state->stateid.data, stateid->data, sizeof(state->stateid.data)) != 0) continue; + clear_bit(NFS_DELEGATED_STATE, &state->flags); get_nfs_open_context(ctx); spin_unlock(&inode->i_lock); err = nfs4_open_delegation_recall(ctx, state, stateid); diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 089da5b..f7e45b4 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -919,8 +919,18 @@ static int update_open_stateid(struct nfs4_state *state, nfs4_stateid *open_stat rcu_read_lock(); deleg_cur = rcu_dereference(nfsi->delegation); - if (deleg_cur == NULL) + if (deleg_cur == NULL) { + if (delegation == NULL && open_stateid != NULL) { + /* + * FIXME: If the state has NFS_DELEGATED_STATE bit + * we catch a race. Maybe should recover its open + * stateid, now we just clear the NFS_DELEGATED_STATE + * bit. + */ + clear_bit(NFS_DELEGATED_STATE, &state->flags); + } goto no_delegation; + } spin_lock(&deleg_cur->lock); if (nfsi->delegation != deleg_cur || -- 1.7.0 >>>> diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c >>>> index 36400d3..c0c0320 100644 >>>> --- a/fs/nfs/nfs4proc.c >>>> +++ b/fs/nfs/nfs4proc.c >>>> @@ -900,8 +900,18 @@ static int update_open_stateid(struct nfs4_state *state, nfs4_stateid *open_stat >>>> >>>> rcu_read_lock(); >>>> deleg_cur = rcu_dereference(nfsi->delegation); >>>> - if (deleg_cur == NULL) >>>> + if (deleg_cur == NULL) { >>>> + if (delegation == NULL && >>>> + test_bit(NFS_DELEGATED_STATE, &state->flags)) { >>> Any reason why we can't ditch the 'test_bit'? >>> >> Because i am not sure it's ok that we just clear_bit at here. >> If you think it's ok, i'd be fine with removing this test_bit. > > How is it different from just clearing the bit? > >>>> + /*FIXME: If the state has NFS_DELEGATED_STATE bit, >>>> + * we catch a race. Maybe should recover its open >>>> + * stateid, here we just clear the NFS_DELEGATED_STATE >>>> + * bit. >>> Can this ever be called with both deleg_cur==NULL and >>> open_stateid==NULL? If so, then we still have a bug. >>> >> Yes, i will add a checking. Thanks very much. >> >>>> + */ >>>> + clear_bit(NFS_DELEGATED_STATE, &state->flags); >>>> + } >>>> goto no_delegation; >>>> + } >>>> >>>> spin_lock(&deleg_cur->lock); >>>> if (nfsi->delegation != deleg_cur || > > Cheers > Trond > > > -- Regards Bian Naimeng