nfsd: allow lock state ids to be revoked and then freed

Revoking state through 'unlock_filesystem' now revokes any lock states
found.  When the stateids are then freed by the client, the revoked
stateids will be cleaned up correctly.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

fs/nfsd/nfs4state.c

@@ -1717,7 +1717,7 @@ void nfsd4_revoke_states(struct net *net, struct super_block *sb)
 	unsigned int idhashval;
 	unsigned int sc_types;
 
-	sc_types = 0;
+	sc_types = SC_TYPE_LOCK;
 
 	spin_lock(&nn->client_lock);
 	for (idhashval = 0; idhashval < CLIENT_HASH_MASK; idhashval++) {
@@ -1728,8 +1728,36 @@ void nfsd4_revoke_states(struct net *net, struct super_block *sb)
 			struct nfs4_stid *stid = find_one_sb_stid(clp, sb,
 								  sc_types);
 			if (stid) {
+				struct nfs4_ol_stateid *stp;
+
 				spin_unlock(&nn->client_lock);
 				switch (stid->sc_type) {
+				case SC_TYPE_LOCK:
+					stp = openlockstateid(stid);
+					mutex_lock_nested(&stp->st_mutex,
+							  LOCK_STATEID_MUTEX);
+					spin_lock(&clp->cl_lock);
+					if (stid->sc_status == 0) {
+						struct nfs4_lockowner *lo =
+							lockowner(stp->st_stateowner);
+						struct nfsd_file *nf;
+
+						stid->sc_status |=
+							SC_STATUS_ADMIN_REVOKED;
+						atomic_inc(&clp->cl_admin_revoked);
+						spin_unlock(&clp->cl_lock);
+						nf = find_any_file(stp->st_stid.sc_file);
+						if (nf) {
+							get_file(nf->nf_file);
+							filp_close(nf->nf_file,
+								   (fl_owner_t)lo);
+							nfsd_file_put(nf);
+						}
+						release_all_access(stp);
+					} else
+						spin_unlock(&clp->cl_lock);
+					mutex_unlock(&stp->st_mutex);
+					break;
 				}
 				nfs4_put_stid(stid);
 				spin_lock(&nn->client_lock);
@@ -4630,8 +4658,18 @@ static void nfsd4_drop_revoked_stid(struct nfs4_stid *s)
 	__releases(&s->sc_client->cl_lock)
 {
 	struct nfs4_client *cl = s->sc_client;
+	LIST_HEAD(reaplist);
+	struct nfs4_ol_stateid *stp;
+	bool unhashed;
 
 	switch (s->sc_type) {
+	case SC_TYPE_LOCK:
+		stp = openlockstateid(s);
+		unhashed = unhash_lock_stateid(stp);
+		spin_unlock(&cl->cl_lock);
+		if (unhashed)
+			nfs4_put_stid(s);
+		break;
 	default:
 		spin_unlock(&cl->cl_lock);
 	}