Re: [PATCH 04/11] nfsd: split sc_status out of sc_type

[Jeff Layton <jlayton@kernel.org>]

On Fri, 2023-11-24 at 11:23 +1100, NeilBrown wrote:
> sc_type identifies the type of a state - open, lock, deleg, layout - and
> also the status of a state - closed or revoked.
> 
> This is a bit untidy and could get worse when "admin-revoked" states are
> added.  So clean it up.
> 
> With this patch, the type is now all that is stored in sc_type.  This is
> zero when the state is first added to ->cl_stateids (causing it to be
> ignored), and is then set appropriately once it is fully initialised.
> It is set under ->cl_lock to ensure atomicity w.r.t lookup.  It is now
> never cleared.
> 
> sc_type is still a bit-set even though at most one bit is set.  This allows
> lookup functions to be given a bitmap of acceptable types.
> 
> sc_type is now an unsigned short rather than char.  There is no value in
> restricting to just 8 bits.
> 
> The status is stored in a separate unsigned short named "sc_status".  It
> has two flags: NFS4_STID_CLOSED and NFS4_STID_REVOKED.
> CLOSED combines NFS4_CLOSED_STID, NFS4_CLOSED_DELEG_STID, and is used
> for LOCK_STID and LAYOUT_STID instead of setting the sc_type to zero.
> These flags are only ever set, never cleared.
> For deleg stateids they are set under the global state_lock.
> For open and lock stateids they are set under ->cl_lock.
> For layout stateids they are set under ->ls_lock
> 
> nfs4_unhash_stid() has been removed, and we never set sc_type = 0.  This
> was only used for LOCK and LAYOUT stids and they now use
> NFS4_STID_CLOSED.
> 
> Also TRACE_DEFINE_NUM() calls for the various STD #define have been
> removed because these things are not enums, and so that call is
> incorrect.
> 
> Signed-off-by: NeilBrown <neilb@suse.de>
> ---
>  fs/nfsd/nfs4layouts.c |   6 +-
>  fs/nfsd/nfs4state.c   | 165 +++++++++++++++++++++---------------------
>  fs/nfsd/state.h       |  40 +++++++---
>  fs/nfsd/trace.h       |  23 +++---
>  4 files changed, 122 insertions(+), 112 deletions(-)
> 
> diff --git a/fs/nfsd/nfs4layouts.c b/fs/nfsd/nfs4layouts.c
> index 5e8096bc5eaa..77656126ad2a 100644
> --- a/fs/nfsd/nfs4layouts.c
> +++ b/fs/nfsd/nfs4layouts.c
> @@ -269,13 +269,13 @@ nfsd4_preprocess_layout_stateid(struct svc_rqst *rqstp,
>  {
>  	struct nfs4_layout_stateid *ls;
>  	struct nfs4_stid *stid;
> -	unsigned char typemask = NFS4_LAYOUT_STID;
> +	unsigned short typemask = NFS4_LAYOUT_STID;
>  	__be32 status;
>  
>  	if (create)
>  		typemask |= (NFS4_OPEN_STID | NFS4_LOCK_STID | NFS4_DELEG_STID);
>  
> -	status = nfsd4_lookup_stateid(cstate, stateid, typemask, &stid,
> +	status = nfsd4_lookup_stateid(cstate, stateid, typemask, 0, &stid,
>  			net_generic(SVC_NET(rqstp), nfsd_net_id));
>  	if (status)
>  		goto out;
> @@ -518,7 +518,7 @@ nfsd4_return_file_layouts(struct svc_rqst *rqstp,
>  		lrp->lrs_present = true;
>  	} else {
>  		trace_nfsd_layoutstate_unhash(&ls->ls_stid.sc_stateid);
> -		nfs4_unhash_stid(&ls->ls_stid);
> +		ls->ls_stid.sc_status |= NFS4_STID_CLOSED;
>  		lrp->lrs_present = false;
>  	}
>  	spin_unlock(&ls->ls_lock);
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 276afcba07a0..b9239f2ebc79 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -1265,11 +1265,6 @@ static void destroy_unhashed_deleg(struct nfs4_delegation *dp)
>  	nfs4_put_stid(&dp->dl_stid);
>  }
>  
> -void nfs4_unhash_stid(struct nfs4_stid *s)
> -{
> -	s->sc_type = 0;
> -}
> -
>  /**
>   * nfs4_delegation_exists - Discover if this delegation already exists
>   * @clp:     a pointer to the nfs4_client we're granting a delegation to
> @@ -1334,7 +1329,7 @@ static bool delegation_hashed(struct nfs4_delegation *dp)
>  }
>  
>  static bool
> -unhash_delegation_locked(struct nfs4_delegation *dp, unsigned char type)
> +unhash_delegation_locked(struct nfs4_delegation *dp, unsigned short statusmask)
>  {
>  	struct nfs4_file *fp = dp->dl_stid.sc_file;
>  
> @@ -1344,8 +1339,9 @@ unhash_delegation_locked(struct nfs4_delegation *dp, unsigned char type)
>  		return false;
>  
>  	if (dp->dl_stid.sc_client->cl_minorversion == 0)
> -		type = NFS4_CLOSED_DELEG_STID;
> -	dp->dl_stid.sc_type = type;
> +		statusmask = NFS4_STID_CLOSED;
> +	dp->dl_stid.sc_status |= statusmask;
> +
>  	/* Ensure that deleg break won't try to requeue it */
>  	++dp->dl_time;
>  	spin_lock(&fp->fi_lock);
> @@ -1361,7 +1357,7 @@ static void destroy_delegation(struct nfs4_delegation *dp)
>  	bool unhashed;
>  
>  	spin_lock(&state_lock);
> -	unhashed = unhash_delegation_locked(dp, NFS4_CLOSED_DELEG_STID);
> +	unhashed = unhash_delegation_locked(dp, NFS4_STID_CLOSED);
>  	spin_unlock(&state_lock);
>  	if (unhashed)
>  		destroy_unhashed_deleg(dp);
> @@ -1375,7 +1371,7 @@ static void revoke_delegation(struct nfs4_delegation *dp)
>  
>  	trace_nfsd_stid_revoke(&dp->dl_stid);
>  
> -	if (dp->dl_stid.sc_type == NFS4_REVOKED_DELEG_STID) {
> +	if (dp->dl_stid.sc_status & NFS4_STID_REVOKED) {
>  		spin_lock(&clp->cl_lock);
>  		refcount_inc(&dp->dl_stid.sc_count);
>  		list_add(&dp->dl_recall_lru, &clp->cl_revoked);
> @@ -1384,8 +1380,8 @@ static void revoke_delegation(struct nfs4_delegation *dp)
>  	destroy_unhashed_deleg(dp);
>  }
>  
> -/* 
> - * SETCLIENTID state 
> +/*
> + * SETCLIENTID state
>   */
>  
>  static unsigned int clientid_hashval(u32 id)
> @@ -1548,7 +1544,7 @@ static bool unhash_lock_stateid(struct nfs4_ol_stateid *stp)
>  	if (!unhash_ol_stateid(stp))
>  		return false;
>  	list_del_init(&stp->st_locks);
> -	nfs4_unhash_stid(&stp->st_stid);
> +	stp->st_stid.sc_status |= NFS4_STID_CLOSED;
>  	return true;
>  }
>  
> @@ -1627,6 +1623,7 @@ static void release_open_stateid(struct nfs4_ol_stateid *stp)
>  	LIST_HEAD(reaplist);
>  
>  	spin_lock(&stp->st_stid.sc_client->cl_lock);
> +	stp->st_stid.sc_status |= NFS4_STID_CLOSED;
>  	if (unhash_open_stateid(stp, &reaplist))
>  		put_ol_stateid_locked(stp, &reaplist);
>  	spin_unlock(&stp->st_stid.sc_client->cl_lock);
> @@ -2235,7 +2232,7 @@ __destroy_client(struct nfs4_client *clp)
>  	spin_lock(&state_lock);
>  	while (!list_empty(&clp->cl_delegations)) {
>  		dp = list_entry(clp->cl_delegations.next, struct nfs4_delegation, dl_perclnt);
> -		unhash_delegation_locked(dp, NFS4_CLOSED_DELEG_STID);
> +		unhash_delegation_locked(dp, NFS4_STID_CLOSED);
>  		list_add(&dp->dl_recall_lru, &reaplist);
>  	}
>  	spin_unlock(&state_lock);
> @@ -2467,14 +2464,16 @@ find_stateid_locked(struct nfs4_client *cl, stateid_t *t)
>  }
>  
>  static struct nfs4_stid *
> -find_stateid_by_type(struct nfs4_client *cl, stateid_t *t, char typemask)
> +find_stateid_by_type(struct nfs4_client *cl, stateid_t *t,
> +		     unsigned short typemask, unsigned short ok_states)
>  {
>  	struct nfs4_stid *s;
>  
>  	spin_lock(&cl->cl_lock);
>  	s = find_stateid_locked(cl, t);
>  	if (s != NULL) {
> -		if (typemask & s->sc_type)
> +		if ((s->sc_status & ~ok_states) == 0 &&
> +		    (typemask & s->sc_type))
>  			refcount_inc(&s->sc_count);
>  		else
>  			s = NULL;
> @@ -4583,7 +4582,8 @@ nfsd4_find_existing_open(struct nfs4_file *fp, struct nfsd4_open *open)
>  			continue;
>  		if (local->st_stateowner != &oo->oo_owner)
>  			continue;
> -		if (local->st_stid.sc_type == NFS4_OPEN_STID) {
> +		if (local->st_stid.sc_type == NFS4_OPEN_STID &&
> +		    !local->st_stid.sc_status) {
>  			ret = local;
>  			refcount_inc(&ret->st_stid.sc_count);
>  			break;
> @@ -4597,17 +4597,10 @@ nfsd4_verify_open_stid(struct nfs4_stid *s)
>  {
>  	__be32 ret = nfs_ok;
>  
> -	switch (s->sc_type) {
> -	default:
> -		break;
> -	case 0:
> -	case NFS4_CLOSED_STID:
> -	case NFS4_CLOSED_DELEG_STID:
> -		ret = nfserr_bad_stateid;
> -		break;
> -	case NFS4_REVOKED_DELEG_STID:
> +	if (s->sc_status & NFS4_STID_REVOKED)
>  		ret = nfserr_deleg_revoked;
> -	}
> +	else if (s->sc_status & NFS4_STID_CLOSED)
> +		ret = nfserr_bad_stateid;
>  	return ret;
>  }
>  
> @@ -4920,9 +4913,9 @@ static int nfsd4_cb_recall_done(struct nfsd4_callback *cb,
>  
>  	trace_nfsd_cb_recall_done(&dp->dl_stid.sc_stateid, task);
>  
> -	if (dp->dl_stid.sc_type == NFS4_CLOSED_DELEG_STID ||
> -	    dp->dl_stid.sc_type == NFS4_REVOKED_DELEG_STID)
> -	        return 1;
> +	if (dp->dl_stid.sc_status)
> +		/* CLOSED or REVOKED */
> +		return 1;
>  
>  	switch (task->tk_status) {
>  	case 0:
> @@ -5167,12 +5160,12 @@ static int share_access_to_flags(u32 share_access)
>  	return share_access == NFS4_SHARE_ACCESS_READ ? RD_STATE : WR_STATE;
>  }
>  
> -static struct nfs4_delegation *find_deleg_stateid(struct nfs4_client *cl, stateid_t *s)
> +static struct nfs4_delegation *find_deleg_stateid(struct nfs4_client *cl,
> +						  stateid_t *s)
>  {
>  	struct nfs4_stid *ret;
>  
> -	ret = find_stateid_by_type(cl, s,
> -				NFS4_DELEG_STID|NFS4_REVOKED_DELEG_STID);
> +	ret = find_stateid_by_type(cl, s, NFS4_DELEG_STID, NFS4_STID_REVOKED);
>  	if (!ret)
>  		return NULL;
>  	return delegstateid(ret);
> @@ -5195,7 +5188,7 @@ nfs4_check_deleg(struct nfs4_client *cl, struct nfsd4_open *open,
>  	deleg = find_deleg_stateid(cl, &open->op_delegate_stateid);
>  	if (deleg == NULL)
>  		goto out;
> -	if (deleg->dl_stid.sc_type == NFS4_REVOKED_DELEG_STID) {
> +	if (deleg->dl_stid.sc_status & NFS4_STID_REVOKED) {
>  		nfs4_put_stid(&deleg->dl_stid);
>  		status = nfserr_deleg_revoked;
>  		goto out;
> @@ -5842,7 +5835,6 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf
>  	} else {
>  		status = nfs4_get_vfs_file(rqstp, fp, current_fh, stp, open, true);
>  		if (status) {
> -			stp->st_stid.sc_type = NFS4_CLOSED_STID;
>  			release_open_stateid(stp);
>  			mutex_unlock(&stp->st_mutex);
>  			goto out;
> @@ -6234,7 +6226,7 @@ nfs4_laundromat(struct nfsd_net *nn)
>  		dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
>  		if (!state_expired(&lt, dp->dl_time))
>  			break;
> -		unhash_delegation_locked(dp, NFS4_REVOKED_DELEG_STID);
> +		unhash_delegation_locked(dp, NFS4_STID_REVOKED);
>  		list_add(&dp->dl_recall_lru, &reaplist);
>  	}
>  	spin_unlock(&state_lock);
> @@ -6473,22 +6465,20 @@ static __be32 nfsd4_validate_stateid(struct nfs4_client *cl, stateid_t *stateid)
>  	status = nfsd4_stid_check_stateid_generation(stateid, s, 1);
>  	if (status)
>  		goto out_unlock;
> +	status = nfsd4_verify_open_stid(s);
> +	if (status)
> +		goto out_unlock;
> +
>  	switch (s->sc_type) {
>  	case NFS4_DELEG_STID:
>  		status = nfs_ok;
>  		break;
> -	case NFS4_REVOKED_DELEG_STID:
> -		status = nfserr_deleg_revoked;
> -		break;
>  	case NFS4_OPEN_STID:
>  	case NFS4_LOCK_STID:
>  		status = nfsd4_check_openowner_confirmed(openlockstateid(s));
>  		break;
>  	default:
>  		printk("unknown stateid type %x\n", s->sc_type);
> -		fallthrough;
> -	case NFS4_CLOSED_STID:
> -	case NFS4_CLOSED_DELEG_STID:
>  		status = nfserr_bad_stateid;
>  	}
>  out_unlock:
> @@ -6498,7 +6488,8 @@ static __be32 nfsd4_validate_stateid(struct nfs4_client *cl, stateid_t *stateid)
>  
>  __be32
>  nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
> -		     stateid_t *stateid, unsigned char typemask,
> +		     stateid_t *stateid,
> +		     unsigned short typemask, unsigned short statusmask,
>  		     struct nfs4_stid **s, struct nfsd_net *nn)
>  {
>  	__be32 status;
> @@ -6509,10 +6500,13 @@ nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
>  	 *  only return revoked delegations if explicitly asked.
>  	 *  otherwise we report revoked or bad_stateid status.
>  	 */
> -	if (typemask & NFS4_REVOKED_DELEG_STID)
> +	if (statusmask & NFS4_STID_REVOKED)
>  		return_revoked = true;
> -	else if (typemask & NFS4_DELEG_STID)
> -		typemask |= NFS4_REVOKED_DELEG_STID;
> +	if (typemask & NFS4_DELEG_STID)
> +		/* Always allow REVOKED for DELEG so we can
> +		 * retturn the appropriate error.
> +		 */
> +		statusmask |= NFS4_STID_REVOKED;
>  
>  	if (ZERO_STATEID(stateid) || ONE_STATEID(stateid) ||
>  		CLOSE_STATEID(stateid))
> @@ -6525,14 +6519,12 @@ nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
>  	}
>  	if (status)
>  		return status;
> -	stid = find_stateid_by_type(cstate->clp, stateid, typemask);
> +	stid = find_stateid_by_type(cstate->clp, stateid, typemask, statusmask);
>  	if (!stid)
>  		return nfserr_bad_stateid;
> -	if ((stid->sc_type == NFS4_REVOKED_DELEG_STID) && !return_revoked) {
> +	if ((stid->sc_status & NFS4_STID_REVOKED) && !return_revoked) {
>  		nfs4_put_stid(stid);
> -		if (cstate->minorversion)
> -			return nfserr_deleg_revoked;
> -		return nfserr_bad_stateid;
> +		return nfserr_deleg_revoked;
>  	}
>  	*s = stid;
>  	return nfs_ok;
> @@ -6543,7 +6535,7 @@ nfs4_find_file(struct nfs4_stid *s, int flags)
>  {
>  	struct nfsd_file *ret = NULL;
>  
> -	if (!s)
> +	if (!s || s->sc_status)
>  		return NULL;
>  
>  	switch (s->sc_type) {
> @@ -6666,7 +6658,8 @@ static __be32 find_cpntf_state(struct nfsd_net *nn, stateid_t *st,
>  		goto out;
>  
>  	*stid = find_stateid_by_type(found, &cps->cp_p_stateid,
> -			NFS4_DELEG_STID|NFS4_OPEN_STID|NFS4_LOCK_STID);
> +				     NFS4_DELEG_STID|NFS4_OPEN_STID|NFS4_LOCK_STID,
> +				     0);
>  	if (*stid)
>  		status = nfs_ok;
>  	else
> @@ -6724,7 +6717,7 @@ nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
>  
>  	status = nfsd4_lookup_stateid(cstate, stateid,
>  				NFS4_DELEG_STID|NFS4_OPEN_STID|NFS4_LOCK_STID,
> -				&s, nn);
> +				0, &s, nn);
>  	if (status == nfserr_bad_stateid)
>  		status = find_cpntf_state(nn, stateid, &s);
>  	if (status)
> @@ -6742,9 +6735,6 @@ nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
>  	case NFS4_LOCK_STID:
>  		status = nfs4_check_olstateid(openlockstateid(s), flags);
>  		break;
> -	default:
> -		status = nfserr_bad_stateid;
> -		break;
>  	}
>  	if (status)
>  		goto out;
> @@ -6823,11 +6813,20 @@ nfsd4_free_stateid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>  
>  	spin_lock(&cl->cl_lock);
>  	s = find_stateid_locked(cl, stateid);
> -	if (!s)
> +	if (!s || s->sc_status & NFS4_STID_CLOSED)
>  		goto out_unlock;
>  	spin_lock(&s->sc_lock);
>  	switch (s->sc_type) {
>  	case NFS4_DELEG_STID:
> +		if (s->sc_status & NFS4_STID_REVOKED) {
> +			spin_unlock(&s->sc_lock);
> +			dp = delegstateid(s);
> +			list_del_init(&dp->dl_recall_lru);
> +			spin_unlock(&cl->cl_lock);
> +			nfs4_put_stid(s);
> +			ret = nfs_ok;
> +			goto out;
> +		}
>  		ret = nfserr_locks_held;
>  		break;
>  	case NFS4_OPEN_STID:
> @@ -6842,14 +6841,6 @@ nfsd4_free_stateid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>  		spin_unlock(&cl->cl_lock);
>  		ret = nfsd4_free_lock_stateid(stateid, s);
>  		goto out;
> -	case NFS4_REVOKED_DELEG_STID:
> -		spin_unlock(&s->sc_lock);
> -		dp = delegstateid(s);
> -		list_del_init(&dp->dl_recall_lru);
> -		spin_unlock(&cl->cl_lock);
> -		nfs4_put_stid(s);
> -		ret = nfs_ok;
> -		goto out;
>  	/* Default falls through and returns nfserr_bad_stateid */
>  	}
>  	spin_unlock(&s->sc_lock);
> @@ -6892,6 +6883,7 @@ static __be32 nfs4_seqid_op_checks(struct nfsd4_compound_state *cstate, stateid_
>   * @seqid: seqid (provided by client)
>   * @stateid: stateid (provided by client)
>   * @typemask: mask of allowable types for this operation
> + * @statusmask: mask of allowed states: 0 or STID_CLOSED
>   * @stpp: return pointer for the stateid found
>   * @nn: net namespace for request
>   *
> @@ -6901,7 +6893,8 @@ static __be32 nfs4_seqid_op_checks(struct nfsd4_compound_state *cstate, stateid_
>   */
>  static __be32
>  nfs4_preprocess_seqid_op(struct nfsd4_compound_state *cstate, u32 seqid,
> -			 stateid_t *stateid, char typemask,
> +			 stateid_t *stateid,
> +			 unsigned short typemask, unsigned short statusmask,
>  			 struct nfs4_ol_stateid **stpp,
>  			 struct nfsd_net *nn)
>  {
> @@ -6912,7 +6905,8 @@ nfs4_preprocess_seqid_op(struct nfsd4_compound_state *cstate, u32 seqid,
>  	trace_nfsd_preprocess(seqid, stateid);
>  
>  	*stpp = NULL;
> -	status = nfsd4_lookup_stateid(cstate, stateid, typemask, &s, nn);
> +	status = nfsd4_lookup_stateid(cstate, stateid,
> +				      typemask, statusmask, &s, nn);
>  	if (status)
>  		return status;
>  	stp = openlockstateid(s);
> @@ -6934,7 +6928,7 @@ static __be32 nfs4_preprocess_confirmed_seqid_op(struct nfsd4_compound_state *cs
>  	struct nfs4_ol_stateid *stp;
>  
>  	status = nfs4_preprocess_seqid_op(cstate, seqid, stateid,
> -						NFS4_OPEN_STID, &stp, nn);
> +					  NFS4_OPEN_STID, 0, &stp, nn);
>  	if (status)
>  		return status;
>  	oo = openowner(stp->st_stateowner);
> @@ -6965,8 +6959,8 @@ nfsd4_open_confirm(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>  		return status;
>  
>  	status = nfs4_preprocess_seqid_op(cstate,
> -					oc->oc_seqid, &oc->oc_req_stateid,
> -					NFS4_OPEN_STID, &stp, nn);
> +					  oc->oc_seqid, &oc->oc_req_stateid,
> +					  NFS4_OPEN_STID, 0, &stp, nn);
>  	if (status)
>  		goto out;
>  	oo = openowner(stp->st_stateowner);
> @@ -7096,18 +7090,20 @@ nfsd4_close(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>  	struct net *net = SVC_NET(rqstp);
>  	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
>  
> -	dprintk("NFSD: nfsd4_close on file %pd\n", 
> +	dprintk("NFSD: nfsd4_close on file %pd\n",
>  			cstate->current_fh.fh_dentry);
>  
>  	status = nfs4_preprocess_seqid_op(cstate, close->cl_seqid,
> -					&close->cl_stateid,
> -					NFS4_OPEN_STID|NFS4_CLOSED_STID,
> -					&stp, nn);
> +					  &close->cl_stateid,
> +					  NFS4_OPEN_STID, NFS4_STID_CLOSED,
> +					  &stp, nn);
>  	nfsd4_bump_seqid(cstate, status);
>  	if (status)
> -		goto out; 
> +		goto out;
>  
> -	stp->st_stid.sc_type = NFS4_CLOSED_STID;
> +	spin_lock(&stp->st_stid.sc_client->cl_lock);
> +	stp->st_stid.sc_status |= NFS4_STID_CLOSED;
> +	spin_unlock(&stp->st_stid.sc_client->cl_lock);
>  
>  	/*
>  	 * Technically we don't _really_ have to increment or copy it, since
> @@ -7149,7 +7145,7 @@ nfsd4_delegreturn(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>  	if ((status = fh_verify(rqstp, &cstate->current_fh, S_IFREG, 0)))
>  		return status;
>  
> -	status = nfsd4_lookup_stateid(cstate, stateid, NFS4_DELEG_STID, &s, nn);
> +	status = nfsd4_lookup_stateid(cstate, stateid, NFS4_DELEG_STID, 0, &s, nn);
>  	if (status)
>  		goto out;
>  	dp = delegstateid(s);
> @@ -7603,9 +7599,10 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>  							&lock_stp, &new);
>  	} else {
>  		status = nfs4_preprocess_seqid_op(cstate,
> -				       lock->lk_old_lock_seqid,
> -				       &lock->lk_old_lock_stateid,
> -				       NFS4_LOCK_STID, &lock_stp, nn);
> +						  lock->lk_old_lock_seqid,
> +						  &lock->lk_old_lock_stateid,
> +						  NFS4_LOCK_STID, 0, &lock_stp,
> +						  nn);
>  	}
>  	if (status)
>  		goto out;
> @@ -7918,8 +7915,8 @@ nfsd4_locku(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>  		 return nfserr_inval;
>  
>  	status = nfs4_preprocess_seqid_op(cstate, locku->lu_seqid,
> -					&locku->lu_stateid, NFS4_LOCK_STID,
> -					&stp, nn);
> +					  &locku->lu_stateid, NFS4_LOCK_STID, 0,
> +					  &stp, nn);
>  	if (status)
>  		goto out;
>  	nf = find_any_file(stp->st_stid.sc_file);
> @@ -8353,7 +8350,7 @@ nfs4_state_shutdown_net(struct net *net)
>  	spin_lock(&state_lock);
>  	list_for_each_safe(pos, next, &nn->del_recall_lru) {
>  		dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
> -		unhash_delegation_locked(dp, NFS4_CLOSED_DELEG_STID);
> +		unhash_delegation_locked(dp, NFS4_STID_CLOSED);
>  		list_add(&dp->dl_recall_lru, &reaplist);
>  	}
>  	spin_unlock(&state_lock);
> diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
> index f96eaa8e9413..bb00dcd4c1ba 100644
> --- a/fs/nfsd/state.h
> +++ b/fs/nfsd/state.h
> @@ -88,17 +88,33 @@ struct nfsd4_callback_ops {
>   */
>  struct nfs4_stid {
>  	refcount_t		sc_count;
> -#define NFS4_OPEN_STID 1
> -#define NFS4_LOCK_STID 2
> -#define NFS4_DELEG_STID 4
> -/* For an open stateid kept around *only* to process close replays: */
> -#define NFS4_CLOSED_STID 8
> +
> +	/* A new stateid is added to the cl_stateids idr early before it
> +	 * is fully initialised.  Its sc_type is then zero.  After
> +	 * initialisation the sc_type it set under cl_lock, and then
> +	 * never changes.
> +	 */
> +#define NFS4_OPEN_STID		BIT(0)
> +#define NFS4_LOCK_STID		BIT(1)
> +#define NFS4_DELEG_STID		BIT(2)
> +#define NFS4_LAYOUT_STID	BIT(3)
> +	unsigned short		sc_type;
> +
> +/* state_lock protects sc_status for delegation stateids.
> + * ->cl_lock protects sc_status for open and lock stateids.
> + * ->st_mutex also protect sc_status for open stateids.
> + * ->ls_lock protects sc_status for layout stateids.
> + */
> +/*
> + * For an open stateid kept around *only* to process close replays.
> + * For deleg stateid, kept in idr until last reference is dropped.
> + */
> +#define NFS4_STID_CLOSED	BIT(0)
>  /* For a deleg stateid kept around only to process free_stateid's: */
> -#define NFS4_REVOKED_DELEG_STID 16
> -#define NFS4_CLOSED_DELEG_STID 32
> -#define NFS4_LAYOUT_STID 64
> +#define NFS4_STID_REVOKED	BIT(1)
> +	unsigned short		sc_status;
> +
>  	struct list_head	sc_cp_list;
> -	unsigned char		sc_type;
>  	stateid_t		sc_stateid;
>  	spinlock_t		sc_lock;
>  	struct nfs4_client	*sc_client;
> @@ -694,15 +710,15 @@ extern __be32 nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
>  		stateid_t *stateid, int flags, struct nfsd_file **filp,
>  		struct nfs4_stid **cstid);
>  __be32 nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
> -		     stateid_t *stateid, unsigned char typemask,
> -		     struct nfs4_stid **s, struct nfsd_net *nn);
> +			    stateid_t *stateid, unsigned short typemask,
> +			    unsigned short statusmask,
> +			    struct nfs4_stid **s, struct nfsd_net *nn);
>  struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct kmem_cache *slab,
>  				  void (*sc_free)(struct nfs4_stid *));
>  int nfs4_init_copy_state(struct nfsd_net *nn, struct nfsd4_copy *copy);
>  void nfs4_free_copy_state(struct nfsd4_copy *copy);
>  struct nfs4_cpntf_state *nfs4_alloc_init_cpntf_state(struct nfsd_net *nn,
>  			struct nfs4_stid *p_stid);
> -void nfs4_unhash_stid(struct nfs4_stid *s);
>  void nfs4_put_stid(struct nfs4_stid *s);
>  void nfs4_inc_and_copy_stateid(stateid_t *dst, struct nfs4_stid *stid);
>  void nfs4_remove_reclaim_record(struct nfs4_client_reclaim *, struct nfsd_net *);
> diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h
> index d1e8cf079b0f..568b4ec9a2af 100644
> --- a/fs/nfsd/trace.h
> +++ b/fs/nfsd/trace.h
> @@ -641,24 +641,18 @@ DEFINE_EVENT(nfsd_stateseqid_class, nfsd_##name, \
>  DEFINE_STATESEQID_EVENT(preprocess);
>  DEFINE_STATESEQID_EVENT(open_confirm);
>  
> -TRACE_DEFINE_ENUM(NFS4_OPEN_STID);
> -TRACE_DEFINE_ENUM(NFS4_LOCK_STID);
> -TRACE_DEFINE_ENUM(NFS4_DELEG_STID);
> -TRACE_DEFINE_ENUM(NFS4_CLOSED_STID);
> -TRACE_DEFINE_ENUM(NFS4_REVOKED_DELEG_STID);
> -TRACE_DEFINE_ENUM(NFS4_CLOSED_DELEG_STID);
> -TRACE_DEFINE_ENUM(NFS4_LAYOUT_STID);
> -
>  #define show_stid_type(x)						\
>  	__print_flags(x, "|",						\
>  		{ NFS4_OPEN_STID,		"OPEN" },		\
>  		{ NFS4_LOCK_STID,		"LOCK" },		\
>  		{ NFS4_DELEG_STID,		"DELEG" },		\
> -		{ NFS4_CLOSED_STID,		"CLOSED" },		\
> -		{ NFS4_REVOKED_DELEG_STID,	"REVOKED" },		\
> -		{ NFS4_CLOSED_DELEG_STID,	"CLOSED_DELEG" },	\
>  		{ NFS4_LAYOUT_STID,		"LAYOUT" })
>  
> +#define show_stid_status(x)						\
> +	__print_flags(x, "|",						\
> +		{ NFS4_STID_CLOSED,		"CLOSED" },		\
> +		{ NFS4_STID_REVOKED,		"REVOKED" })		\
> +
>  DECLARE_EVENT_CLASS(nfsd_stid_class,
>  	TP_PROTO(
>  		const struct nfs4_stid *stid
> @@ -666,6 +660,7 @@ DECLARE_EVENT_CLASS(nfsd_stid_class,
>  	TP_ARGS(stid),
>  	TP_STRUCT__entry(
>  		__field(unsigned long, sc_type)
> +		__field(unsigned long, sc_status)
>  		__field(int, sc_count)
>  		__field(u32, cl_boot)
>  		__field(u32, cl_id)
> @@ -676,16 +671,18 @@ DECLARE_EVENT_CLASS(nfsd_stid_class,
>  		const stateid_t *stp = &stid->sc_stateid;
>  
>  		__entry->sc_type = stid->sc_type;
> +		__entry->sc_status = stid->sc_status;
>  		__entry->sc_count = refcount_read(&stid->sc_count);
>  		__entry->cl_boot = stp->si_opaque.so_clid.cl_boot;
>  		__entry->cl_id = stp->si_opaque.so_clid.cl_id;
>  		__entry->si_id = stp->si_opaque.so_id;
>  		__entry->si_generation = stp->si_generation;
>  	),
> -	TP_printk("client %08x:%08x stateid %08x:%08x ref=%d type=%s",
> +	TP_printk("client %08x:%08x stateid %08x:%08x ref=%d type=%s state=%s",
>  		__entry->cl_boot, __entry->cl_id,
>  		__entry->si_id, __entry->si_generation,
> -		__entry->sc_count, show_stid_type(__entry->sc_type)
> +		__entry->sc_count, show_stid_type(__entry->sc_type),
> +		show_stid_status(__entry->sc_status)
>  	)
>  );
>  

Very nice. This is long overdue.

Reviewed-by: Jeff Layton <jlayton@kernel.org>