[PATCH 5/6] nfsd: allow open state ids to be revoked and then freed

[NeilBrown <neilb@suse.de>]

Revoking state through 'unlock_filesystem' now revokes any open states
found.  When the stateids are then freed by the client, the revoked
stateids will be cleaned up correctly.

Possibly the related lock states should be revoked too, but a
subsequent patch will do that for all lock state on the superblock.

Signed-off-by: NeilBrown <neilb@suse.de>
---
 fs/nfsd/nfs4state.c | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index c2e064f6c7c4..ed879f68944b 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 = NFS4_LOCK_STID;
+	sc_types = NFS4_OPEN_STID | NFS4_LOCK_STID;
 
 	spin_lock(&nn->client_lock);
 	for (idhashval = 0; idhashval < CLIENT_HASH_MASK; idhashval++) {
@@ -1723,6 +1723,18 @@ void nfsd4_revoke_states(struct net *net, struct super_block *sb)
 
 				spin_unlock(&nn->client_lock);
 				switch (stid->sc_type) {
+				case NFS4_OPEN_STID:
+					stp = openlockstateid(stid);
+					mutex_lock_nested(&stp->st_mutex,
+							  OPEN_STATEID_MUTEX);
+					if (stid->sc_type == NFS4_OPEN_STID) {
+						release_all_access(stp);
+						stid->sc_type =
+							NFS4_ADMIN_REVOKED_STID;
+						atomic_inc(&clp->cl_admin_revoked);
+					}
+					mutex_unlock(&stp->st_mutex);
+					break;
 				case NFS4_LOCK_STID:
 					stp = openlockstateid(stid);
 					mutex_lock_nested(&stp->st_mutex,
@@ -4681,10 +4693,18 @@ 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;
+	LIST_HEAD(reaplist);
 	struct nfs4_ol_stateid *stp;
 	bool unhashed;
 
 	switch (s->sc_type) {
+	case NFS4_ADMIN_REVOKED_STID:
+		stp = openlockstateid(s);
+		if (unhash_open_stateid(stp, &reaplist))
+			put_ol_stateid_locked(stp, &reaplist);
+		spin_unlock(&cl->cl_lock);
+		free_ol_stateid_reaplist(&reaplist);
+		break;
 	case NFS4_ADMIN_REVOKED_LOCK_STID:
 		stp = openlockstateid(s);
 		unhashed = unhash_lock_stateid(stp);
-- 
2.42.0