NFSv4: Revoke the delegation on success in nfs4_delegreturn_done()

If the delegation was successfully returned, then mark it as revoked.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

fs/nfs/delegation.c

@@ -806,6 +806,42 @@ void nfs_remove_bad_delegation(struct inode *inode,
 }
 EXPORT_SYMBOL_GPL(nfs_remove_bad_delegation);
 
+void nfs_delegation_mark_returned(struct inode *inode,
+		const nfs4_stateid *stateid)
+{
+	struct nfs_delegation *delegation;
+
+	if (!inode)
+		return;
+
+	rcu_read_lock();
+	delegation = rcu_dereference(NFS_I(inode)->delegation);
+	if (!delegation)
+		goto out_rcu_unlock;
+
+	spin_lock(&delegation->lock);
+	if (!nfs4_stateid_match_other(stateid, &delegation->stateid))
+		goto out_spin_unlock;
+	if (stateid->seqid) {
+		/* If delegation->stateid is newer, dont mark as returned */
+		if (nfs4_stateid_is_newer(&delegation->stateid, stateid))
+			goto out_clear_returning;
+		if (delegation->stateid.seqid != stateid->seqid)
+			delegation->stateid.seqid = stateid->seqid;
+	}
+
+	set_bit(NFS_DELEGATION_REVOKED, &delegation->flags);
+
+out_clear_returning:
+	clear_bit(NFS_DELEGATION_RETURNING, &delegation->flags);
+out_spin_unlock:
+	spin_unlock(&delegation->lock);
+out_rcu_unlock:
+	rcu_read_unlock();
+
+	nfs_inode_find_state_and_recover(inode, stateid);
+}
+
 /**
  * nfs_expire_unused_delegation_types
  * @clp: client to process

fs/nfs/delegation.h

@@ -53,6 +53,7 @@ void nfs_expire_unreferenced_delegations(struct nfs_client *clp);
 int nfs_client_return_marked_delegations(struct nfs_client *clp);
 int nfs_delegations_present(struct nfs_client *clp);
 void nfs_remove_bad_delegation(struct inode *inode, const nfs4_stateid *stateid);
+void nfs_delegation_mark_returned(struct inode *inode, const nfs4_stateid *stateid);
 
 void nfs_delegation_mark_reclaim(struct nfs_client *clp);
 void nfs_delegation_reap_unclaimed(struct nfs_client *clp);

fs/nfs/nfs4proc.c

@@ -6214,6 +6214,7 @@ static void nfs4_delegreturn_done(struct rpc_task *task, void *calldata)
 		if (exception.retry)
 			goto out_restart;
 	}
+	nfs_delegation_mark_returned(data->inode, data->args.stateid);
 	data->rpc_status = task->tk_status;
 	return;
 out_restart: