nfsd: Migrate the stateid reference into nfs4_find_stateid_by_type()

Allow nfs4_find_stateid_by_type to take the stateid reference, while
still holding the &cl->cl_lock. Necessary step toward client_mutex
removal.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

fs/nfsd/nfs4state.c

@@ -1696,8 +1696,12 @@ find_stateid_by_type(struct nfs4_client *cl, stateid_t *t, char typemask)
 
 	spin_lock(&cl->cl_lock);
 	s = find_stateid_locked(cl, t);
-	if (s != NULL && !(typemask & s->sc_type))
-		s = NULL;
+	if (s != NULL) {
+		if (typemask & s->sc_type)
+			atomic_inc(&s->sc_count);
+		else
+			s = NULL;
+	}
 	spin_unlock(&cl->cl_lock);
 	return s;
 }
@@ -3326,8 +3330,6 @@ static struct nfs4_delegation *find_deleg_stateid(struct nfs4_client *cl, statei
 	ret = find_stateid_by_type(cl, s, NFS4_DELEG_STID);
 	if (!ret)
 		return NULL;
-	/* FIXME: move into find_stateid_by_type */
-	atomic_inc(&ret->sc_count);
 	return delegstateid(ret);
 }
 
@@ -4170,8 +4172,6 @@ nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
 	*s = find_stateid_by_type(cstate->clp, stateid, typemask);
 	if (!*s)
 		return nfserr_bad_stateid;
-	/* FIXME: move into find_stateid_by_type */
-	atomic_inc(&(*s)->sc_count);
 	return nfs_ok;
 }