NFSv4.1: Only reap expired delegations

mainline inclusion
from mainline-v5.3-rc4
commit ad114089
category: bugfix
bugzilla: NA
CVE: NA

--------------------------------

Fix nfs_reap_expired_delegations() to ensure that we only reap delegations
that are actually expired, rather than triggering on random errors.

Fixes: 45870d69 ("NFSv4.1: Test delegation stateids when server...")
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

Conflicts:
	fs/nfs/delegation.c
Signed-off-by: NZhang Xiaoxu <zhangxiaoxu5@huawei.com>
Reviewed-by: NZhang Yi <yi.zhang@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

fs/nfs/delegation.c

@@ -1044,6 +1044,21 @@ void nfs_mark_test_expired_all_delegations(struct nfs_client *clp)
 	rcu_read_unlock();
 }
 
+static void
+nfs_delegation_test_free_expired(struct inode *inode,
+		nfs4_stateid *stateid, struct rpc_cred *cred)
+{
+	struct nfs_server *server = NFS_SERVER(inode);
+	const struct nfs4_minor_version_ops *ops = server->nfs_client->cl_mvops;
+	int status;
+
+	if (!cred)
+		return;
+	status = ops->test_and_free_expired(server, stateid, cred);
+	if (status == -NFS4ERR_EXPIRED || status == -NFS4ERR_BAD_STATEID)
+		nfs_remove_bad_delegation(inode, stateid);
+}
+
 /**
  * nfs_reap_expired_delegations - reap expired delegations
  * @clp: nfs_client to process
@@ -1055,7 +1070,6 @@ void nfs_mark_test_expired_all_delegations(struct nfs_client *clp)
  */
 void nfs_reap_expired_delegations(struct nfs_client *clp)
 {
-	const struct nfs4_minor_version_ops *ops = clp->cl_mvops;
 	struct nfs_delegation *delegation;
 	struct nfs_server *server;
 	struct inode *inode;
@@ -1086,11 +1100,7 @@ void nfs_reap_expired_delegations(struct nfs_client *clp)
 			nfs4_stateid_copy(&stateid, &delegation->stateid);
 			clear_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags);
 			rcu_read_unlock();
-			if (cred != NULL &&
-			    ops->test_and_free_expired(server, &stateid, cred) < 0) {
-				nfs_revoke_delegation(inode, &stateid);
-				nfs_inode_find_state_and_recover(inode, &stateid);
-			}
+			nfs_delegation_test_free_expired(inode, &stateid, cred);
 			put_rpccred(cred);
 			if (nfs4_server_rebooted(clp)) {
 				nfs_inode_mark_test_expired_delegation(server,inode);