Return-Path: linux-nfs-owner@vger.kernel.org Received: from fieldses.org ([174.143.236.118]:48421 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935482Ab3DHN4d (ORCPT ); Mon, 8 Apr 2013 09:56:33 -0400 Date: Mon, 8 Apr 2013 09:56:27 -0400 From: "J. Bruce Fields" To: Yanchuan Nian Cc: linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] nfsd: fix bug on nfs4 stateid deallocation Message-ID: <20130408135627.GC15177@fieldses.org> References: <1362962774-5141-1-git-send-email-ycnian@gmail.com> <20130311150208.GB16309@fieldses.org> <20130402015044.GA12158@fieldses.org> <20130403105843.GA22704@mail.example.com> <20130403185508.GE6044@fieldses.org> <20130404140403.GA2134@localhost.localdomain> <20130405142042.GB2335@fieldses.org> <20130408135418.GA6489@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20130408135418.GA6489@localhost.localdomain> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Mon, Apr 08, 2013 at 09:54:18PM +0800, Yanchuan Nian wrote: > On Fri, Apr 05, 2013 at 10:20:42AM -0400, J. Bruce Fields wrote: > > Actually, I find encode_seqid_op_tail completely confusing, and I don't > > see why it's necessary--it would seem more straightforward to do the > > seqid bump in the procedure itself. How about the following? > > Sounds OK. I test it with some basic opens/closes. All goes well. Good, thanks! --b. > > > > --b. > > > > commit e58235072acd52ecab71d498b2b06633a2a0c376 > > Author: J. Bruce Fields > > Date: Mon Apr 1 16:37:12 2013 -0400 > > > > nfsd4: cleanup handling of nfsv4.0 closed stateid's > > > > Closed stateid's are kept around a little while to handle close replays > > in the 4.0 case. So we stash them in the last-used stateid in the > > oo_last_closed_stateid field of the open owner. We can free that in > > encode_seqid_op_tail once the seqid on the open owner is next > > incremented. But we don't want to do that on the close itself; so we > > set NFS4_OO_PURGE_CLOSE flag set on the open owner, skip freeing it the > > first time through encode_seqid_op_tail, then when we see that flag set > > next time we free it. > > > > This is unnecessarily baroque. > > > > Instead, just move the logic that increments the seqid out of the xdr > > code and into the operation code itself. > > > > The justification given for the current placement is that we need to > > wait till the last minute to be sure we know whether the status is a > > sequence-id-mutating error or not, but examination of the code shows > > that can't actually happen. > > > > Signed-off-by: J. Bruce Fields > > > > diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c > > index a9b707b..609e1e2 100644 > > --- a/fs/nfsd/nfs4proc.c > > +++ b/fs/nfsd/nfs4proc.c > > @@ -415,7 +415,8 @@ out: > > nfsd4_cleanup_open_state(open, status); > > if (open->op_openowner) > > cstate->replay_owner = &open->op_openowner->oo_owner; > > - else > > + nfsd4_bump_seqid(cstate, status); > > + if (!cstate->replay_owner) > > nfs4_unlock_state(); > > return status; > > } > > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > > index 795b24d..bcd2339 100644 > > --- a/fs/nfsd/nfs4state.c > > +++ b/fs/nfsd/nfs4state.c > > @@ -720,6 +720,28 @@ dump_sessionid(const char *fn, struct nfs4_sessionid *sessionid) > > } > > #endif > > > > +/* > > + * Bump the seqid on cstate->replay_owner, and clear replay_owner if it > > + * won't be used for replay. > > + */ > > +void nfsd4_bump_seqid(struct nfsd4_compound_state *cstate, __be32 nfserr) > > +{ > > + struct nfs4_stateowner *so = cstate->replay_owner; > > + > > + if (nfserr == nfserr_replay_me) > > + return; > > + > > + if (!seqid_mutating_err(ntohl(nfserr))) { > > + cstate->replay_owner = NULL; > > + return; > > + } > > + if (!so) > > + return; > > + if (so->so_is_open_owner) > > + release_last_closed_stateid(openowner(so)); > > + so->so_seqid++; > > + return; > > +} > > > > static void > > gen_sessionid(struct nfsd4_session *ses) > > @@ -3702,6 +3724,7 @@ nfsd4_open_confirm(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, > > nfsd4_client_record_create(oo->oo_owner.so_client); > > status = nfs_ok; > > out: > > + nfsd4_bump_seqid(cstate, status); > > if (!cstate->replay_owner) > > nfs4_unlock_state(); > > return status; > > @@ -3785,31 +3808,12 @@ nfsd4_open_downgrade(struct svc_rqst *rqstp, > > memcpy(&od->od_stateid, &stp->st_stid.sc_stateid, sizeof(stateid_t)); > > status = nfs_ok; > > out: > > + nfsd4_bump_seqid(cstate, status); > > if (!cstate->replay_owner) > > nfs4_unlock_state(); > > return status; > > } > > > > -void nfsd4_purge_closed_stateid(struct nfs4_stateowner *so) > > -{ > > - struct nfs4_openowner *oo; > > - struct nfs4_ol_stateid *s; > > - > > - if (!so->so_is_open_owner) > > - return; > > - oo = openowner(so); > > - s = oo->oo_last_closed_stid; > > - if (!s) > > - return; > > - if (!(oo->oo_flags & NFS4_OO_PURGE_CLOSE)) { > > - /* Release the last_closed_stid on the next seqid bump: */ > > - oo->oo_flags |= NFS4_OO_PURGE_CLOSE; > > - return; > > - } > > - oo->oo_flags &= ~NFS4_OO_PURGE_CLOSE; > > - release_last_closed_stateid(oo); > > -} > > - > > static void nfsd4_close_open_stateid(struct nfs4_ol_stateid *s) > > { > > unhash_open_stateid(s); > > @@ -3838,17 +3842,20 @@ nfsd4_close(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, > > &close->cl_stateid, > > NFS4_OPEN_STID|NFS4_CLOSED_STID, > > &stp, nn); > > + nfsd4_bump_seqid(cstate, status); > > if (status) > > goto out; > > oo = openowner(stp->st_stateowner); > > - status = nfs_ok; > > update_stateid(&stp->st_stid.sc_stateid); > > memcpy(&close->cl_stateid, &stp->st_stid.sc_stateid, sizeof(stateid_t)); > > > > nfsd4_close_open_stateid(stp); > > - release_last_closed_stateid(oo); > > - oo->oo_flags &= ~NFS4_OO_PURGE_CLOSE; > > - oo->oo_last_closed_stid = stp; > > + > > + if (cstate->minorversion) { > > + unhash_stid(&stp->st_stid); > > + free_generic_stateid(stp); > > + } else > > + oo->oo_last_closed_stid = stp; > > > > if (list_empty(&oo->oo_owner.so_stateids)) { > > if (cstate->minorversion) { > > @@ -4270,6 +4277,7 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, > > out: > > if (status && new_state) > > release_lockowner(lock_sop); > > + nfsd4_bump_seqid(cstate, status); > > if (!cstate->replay_owner) > > nfs4_unlock_state(); > > if (file_lock) > > @@ -4439,6 +4447,7 @@ nfsd4_locku(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, > > memcpy(&locku->lu_stateid, &stp->st_stid.sc_stateid, sizeof(stateid_t)); > > > > out: > > + nfsd4_bump_seqid(cstate, status); > > if (!cstate->replay_owner) > > nfs4_unlock_state(); > > if (file_lock) > > diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c > > index 700de01..a5e8a64 100644 > > --- a/fs/nfsd/nfs4xdr.c > > +++ b/fs/nfsd/nfs4xdr.c > > @@ -1701,28 +1701,6 @@ static void write_cinfo(__be32 **p, struct nfsd4_change_info *c) > > \ > > save = resp->p; > > > > -/* > > - * Routine for encoding the result of a "seqid-mutating" NFSv4 operation. This > > - * is where sequence id's are incremented, and the replay cache is filled. > > - * Note that we increment sequence id's here, at the last moment, so we're sure > > - * we know whether the error to be returned is a sequence id mutating error. > > - */ > > - > > -static void encode_seqid_op_tail(struct nfsd4_compoundres *resp, __be32 *save, __be32 nfserr) > > -{ > > - struct nfs4_stateowner *stateowner = resp->cstate.replay_owner; > > - > > - if (seqid_mutating_err(ntohl(nfserr)) && stateowner) { > > - stateowner->so_seqid++; > > - stateowner->so_replay.rp_status = nfserr; > > - stateowner->so_replay.rp_buflen = > > - (char *)resp->p - (char *)save; > > - memcpy(stateowner->so_replay.rp_buf, save, > > - stateowner->so_replay.rp_buflen); > > - nfsd4_purge_closed_stateid(stateowner); > > - } > > -} > > - > > /* Encode as an array of strings the string given with components > > * separated @sep, escaped with esc_enter and esc_exit. > > */ > > @@ -2667,7 +2645,6 @@ nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_c > > if (!nfserr) > > nfsd4_encode_stateid(resp, &close->cl_stateid); > > > > - encode_seqid_op_tail(resp, save, nfserr); > > return nfserr; > > } > > > > @@ -2770,7 +2747,6 @@ nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lo > > else if (nfserr == nfserr_denied) > > nfsd4_encode_lock_denied(resp, &lock->lk_denied); > > > > - encode_seqid_op_tail(resp, save, nfserr); > > return nfserr; > > } > > > > @@ -2790,7 +2766,6 @@ nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_l > > if (!nfserr) > > nfsd4_encode_stateid(resp, &locku->lu_stateid); > > > > - encode_seqid_op_tail(resp, save, nfserr); > > return nfserr; > > } > > > > @@ -2885,7 +2860,6 @@ nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_op > > } > > /* XXX save filehandle here */ > > out: > > - encode_seqid_op_tail(resp, save, nfserr); > > return nfserr; > > } > > > > @@ -2897,7 +2871,6 @@ nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct > > if (!nfserr) > > nfsd4_encode_stateid(resp, &oc->oc_resp_stateid); > > > > - encode_seqid_op_tail(resp, save, nfserr); > > return nfserr; > > } > > > > @@ -2909,7 +2882,6 @@ nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struc > > if (!nfserr) > > nfsd4_encode_stateid(resp, &od->od_stateid); > > > > - encode_seqid_op_tail(resp, save, nfserr); > > return nfserr; > > } > > > > @@ -3567,6 +3539,7 @@ __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 pad) > > void > > nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op) > > { > > + struct nfs4_stateowner *so = resp->cstate.replay_owner; > > __be32 *statp; > > __be32 *p; > > > > @@ -3583,6 +3556,11 @@ nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op) > > /* nfsd4_check_drc_limit guarantees enough room for error status */ > > if (!op->status) > > op->status = nfsd4_check_resp_size(resp, 0); > > + if (so) { > > + so->so_replay.rp_status = op->status; > > + so->so_replay.rp_buflen = (char *)resp->p - (char *)(statp+1); > > + memcpy(so->so_replay.rp_buf, statp+1, so->so_replay.rp_buflen); > > + } > > status: > > /* > > * Note: We write the status directly, instead of using WRITE32(), > > diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h > > index 7674bc8..13ec485 100644 > > --- a/fs/nfsd/state.h > > +++ b/fs/nfsd/state.h > > @@ -355,7 +355,6 @@ struct nfs4_openowner { > > struct nfs4_ol_stateid *oo_last_closed_stid; > > time_t oo_time; /* time of placement on so_close_lru */ > > #define NFS4_OO_CONFIRMED 1 > > -#define NFS4_OO_PURGE_CLOSE 2 > > #define NFS4_OO_NEW 4 > > unsigned char oo_flags; > > }; > > @@ -363,7 +362,7 @@ struct nfs4_openowner { > > struct nfs4_lockowner { > > struct nfs4_stateowner lo_owner; /* must be first element */ > > struct list_head lo_owner_ino_hash; /* hash by owner,file */ > > - struct list_head lo_perstateid; /* for lockowners only */ > > + struct list_head lo_perstateid; > > struct list_head lo_list; /* for temporary uses */ > > }; > > > > @@ -477,7 +476,6 @@ extern struct nfs4_client_reclaim *nfs4_client_to_reclaim(const char *name, > > struct nfsd_net *nn); > > extern bool nfs4_has_reclaimed_state(const char *name, struct nfsd_net *nn); > > extern void put_client_renew(struct nfs4_client *clp); > > -extern void nfsd4_purge_closed_stateid(struct nfs4_stateowner *); > > > > /* nfs4recover operations */ > > extern int nfsd4_client_tracking_init(struct net *net); > > diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h > > index 40e05e6..3b271d2 100644 > > --- a/fs/nfsd/xdr4.h > > +++ b/fs/nfsd/xdr4.h > > @@ -623,6 +623,7 @@ extern __be32 nfsd4_test_stateid(struct svc_rqst *rqstp, > > struct nfsd4_compound_state *, struct nfsd4_test_stateid *test_stateid); > > extern __be32 nfsd4_free_stateid(struct svc_rqst *rqstp, > > struct nfsd4_compound_state *, struct nfsd4_free_stateid *free_stateid); > > +extern void nfsd4_bump_seqid(struct nfsd4_compound_state *, __be32 nfserr); > > #endif > > > > /*