[PATCH 4/6] nfsd: allow lock state ids to be revoked and then freed

[NeilBrown <neilb@xxxxxxx>]

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.

Signed-off-by: NeilBrown <neilb@xxxxxxx>
---
 fs/nfsd/nfs4state.c | 36 +++++++++++++++++++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 13484a9cef21..c2e064f6c7c4 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1708,7 +1708,7 @@ void nfsd4_revoke_states(struct net *net, struct super_block *sb)
 	unsigned int idhashval;
 	unsigned short sc_types;
 
-	sc_types = 0;
+	sc_types = NFS4_LOCK_STID;
 
 	spin_lock(&nn->client_lock);
 	for (idhashval = 0; idhashval < CLIENT_HASH_MASK; idhashval++) {
@@ -1719,8 +1719,33 @@ 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 NFS4_LOCK_STID:
+					stp = openlockstateid(stid);
+					mutex_lock_nested(&stp->st_mutex,
+							  LOCK_STATEID_MUTEX);
+					if (stid->sc_type == NFS4_LOCK_STID) {
+						struct nfs4_lockowner *lo =
+							lockowner(stp->st_stateowner);
+						struct nfsd_file *nf;
+
+						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);
+						stid->sc_type =
+							NFS4_ADMIN_REVOKED_LOCK_STID;
+						atomic_inc(&clp->cl_admin_revoked);
+					}
+					mutex_unlock(&stp->st_mutex);
+					break;
 				}
 				nfs4_put_stid(stid);
 				spin_lock(&nn->client_lock);
@@ -4656,8 +4681,17 @@ nfsd4_find_existing_open(struct nfs4_file *fp, struct nfsd4_open *open)
 static void nfsd_drop_revoked_stid(struct nfs4_stid *s)
 {
 	struct nfs4_client *cl = s->sc_client;
+	struct nfs4_ol_stateid *stp;
+	bool unhashed;
 
 	switch (s->sc_type) {
+	case NFS4_ADMIN_REVOKED_LOCK_STID:
+		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);
 	}
-- 
2.42.0