1 files changed, 192 insertions, 21 deletions

diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index 322c2585bc34..dff600ae0d74 100644
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -41,6 +41,17 @@ void nfs_mark_delegation_referenced(struct nfs_delegation *delegation)
 	set_bit(NFS_DELEGATION_REFERENCED, &delegation->flags);
 }
 
+static bool
+nfs4_is_valid_delegation(const struct nfs_delegation *delegation,
+		fmode_t flags)
+{
+	if (delegation != NULL && (delegation->type & flags) == flags &&
+	    !test_bit(NFS_DELEGATION_REVOKED, &delegation->flags) &&
+	    !test_bit(NFS_DELEGATION_RETURNING, &delegation->flags))
+		return true;
+	return false;
+}
+
 static int
 nfs4_do_check_delegation(struct inode *inode, fmode_t flags, bool mark)
 {
@@ -50,8 +61,7 @@ nfs4_do_check_delegation(struct inode *inode, fmode_t flags, bool mark)
 	flags &= FMODE_READ|FMODE_WRITE;
 	rcu_read_lock();
 	delegation = rcu_dereference(NFS_I(inode)->delegation);
-	if (delegation != NULL && (delegation->type & flags) == flags &&
-	    !test_bit(NFS_DELEGATION_RETURNING, &delegation->flags)) {
+	if (nfs4_is_valid_delegation(delegation, flags)) {
 		if (mark)
 			nfs_mark_delegation_referenced(delegation);
 		ret = 1;
@@ -185,15 +195,13 @@ void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred,
 			rcu_read_unlock();
 			put_rpccred(oldcred);
 			trace_nfs4_reclaim_delegation(inode, res->delegation_type);
-		} else {
-			/* We appear to have raced with a delegation return. */
-			spin_unlock(&delegation->lock);
-			rcu_read_unlock();
-			nfs_inode_set_delegation(inode, cred, res);
+			return;
 		}
-	} else {
-		rcu_read_unlock();
+		/* We appear to have raced with a delegation return. */
+		spin_unlock(&delegation->lock);
 	}
+	rcu_read_unlock();
+	nfs_inode_set_delegation(inode, cred, res);
 }
 
 static int nfs_do_return_delegation(struct inode *inode, struct nfs_delegation *delegation, int issync)
@@ -642,28 +650,49 @@ static void nfs_client_mark_return_unused_delegation_types(struct nfs_client *cl
 	rcu_read_unlock();
 }
 
-static void nfs_revoke_delegation(struct inode *inode)
+static void nfs_mark_delegation_revoked(struct nfs_server *server,
+		struct nfs_delegation *delegation)
+{
+	set_bit(NFS_DELEGATION_REVOKED, &delegation->flags);
+	delegation->stateid.type = NFS4_INVALID_STATEID_TYPE;
+	nfs_mark_return_delegation(server, delegation);
+}
+
+static bool nfs_revoke_delegation(struct inode *inode,
+		const nfs4_stateid *stateid)
 {
 	struct nfs_delegation *delegation;
+	nfs4_stateid tmp;
+	bool ret = false;
+
 	rcu_read_lock();
 	delegation = rcu_dereference(NFS_I(inode)->delegation);
-	if (delegation != NULL) {
-		set_bit(NFS_DELEGATION_REVOKED, &delegation->flags);
-		nfs_mark_return_delegation(NFS_SERVER(inode), delegation);
-	}
+	if (delegation == NULL)
+		goto out;
+	if (stateid == NULL) {
+		nfs4_stateid_copy(&tmp, &delegation->stateid);
+		stateid = &tmp;
+	} else if (!nfs4_stateid_match(stateid, &delegation->stateid))
+		goto out;
+	nfs_mark_delegation_revoked(NFS_SERVER(inode), delegation);
+	ret = true;
+out:
 	rcu_read_unlock();
+	if (ret)
+		nfs_inode_find_state_and_recover(inode, stateid);
+	return ret;
 }
 
-void nfs_remove_bad_delegation(struct inode *inode)
+void nfs_remove_bad_delegation(struct inode *inode,
+		const nfs4_stateid *stateid)
 {
 	struct nfs_delegation *delegation;
 
-	nfs_revoke_delegation(inode);
+	if (!nfs_revoke_delegation(inode, stateid))
+		return;
 	delegation = nfs_inode_detach_delegation(inode);
-	if (delegation) {
-		nfs_inode_find_state_and_recover(inode, &delegation->stateid);
+	if (delegation)
 		nfs_free_delegation(delegation);
-	}
 }
 EXPORT_SYMBOL_GPL(nfs_remove_bad_delegation);
 
@@ -786,8 +815,15 @@ static void nfs_delegation_mark_reclaim_server(struct nfs_server *server)
 {
 	struct nfs_delegation *delegation;
 
-	list_for_each_entry_rcu(delegation, &server->delegations, super_list)
+	list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
+		/*
+		 * If the delegation may have been admin revoked, then we
+		 * cannot reclaim it.
+		 */
+		if (test_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags))
+			continue;
 		set_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
+	}
 }
 
 /**
@@ -851,6 +887,141 @@ restart:
 	rcu_read_unlock();
 }
 
+static inline bool nfs4_server_rebooted(const struct nfs_client *clp)
+{
+	return (clp->cl_state & (BIT(NFS4CLNT_CHECK_LEASE) |
+				BIT(NFS4CLNT_LEASE_EXPIRED) |
+				BIT(NFS4CLNT_SESSION_RESET))) != 0;
+}
+
+static void nfs_mark_test_expired_delegation(struct nfs_server *server,
+	    struct nfs_delegation *delegation)
+{
+	if (delegation->stateid.type == NFS4_INVALID_STATEID_TYPE)
+		return;
+	clear_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
+	set_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags);
+	set_bit(NFS4CLNT_DELEGATION_EXPIRED, &server->nfs_client->cl_state);
+}
+
+static void nfs_inode_mark_test_expired_delegation(struct nfs_server *server,
+		struct inode *inode)
+{
+	struct nfs_delegation *delegation;
+
+	rcu_read_lock();
+	delegation = rcu_dereference(NFS_I(inode)->delegation);
+	if (delegation)
+		nfs_mark_test_expired_delegation(server, delegation);
+	rcu_read_unlock();
+
+}
+
+static void nfs_delegation_mark_test_expired_server(struct nfs_server *server)
+{
+	struct nfs_delegation *delegation;
+
+	list_for_each_entry_rcu(delegation, &server->delegations, super_list)
+		nfs_mark_test_expired_delegation(server, delegation);
+}
+
+/**
+ * nfs_mark_test_expired_all_delegations - mark all delegations for testing
+ * @clp: nfs_client to process
+ *
+ * Iterates through all the delegations associated with this server and
+ * marks them as needing to be checked for validity.
+ */
+void nfs_mark_test_expired_all_delegations(struct nfs_client *clp)
+{
+	struct nfs_server *server;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
+		nfs_delegation_mark_test_expired_server(server);
+	rcu_read_unlock();
+}
+
+/**
+ * nfs_reap_expired_delegations - reap expired delegations
+ * @clp: nfs_client to process
+ *
+ * Iterates through all the delegations associated with this server and
+ * checks if they have may have been revoked. This function is usually
+ * expected to be called in cases where the server may have lost its
+ * lease.
+ */
+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;
+	struct rpc_cred *cred;
+	nfs4_stateid stateid;
+
+restart:
+	rcu_read_lock();
+	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+		list_for_each_entry_rcu(delegation, &server->delegations,
+								super_list) {
+			if (test_bit(NFS_DELEGATION_RETURNING,
+						&delegation->flags))
+				continue;
+			if (test_bit(NFS_DELEGATION_TEST_EXPIRED,
+						&delegation->flags) == 0)
+				continue;
+			if (!nfs_sb_active(server->super))
+				continue;
+			inode = nfs_delegation_grab_inode(delegation);
+			if (inode == NULL) {
+				rcu_read_unlock();
+				nfs_sb_deactive(server->super);
+				goto restart;
+			}
+			cred = get_rpccred_rcu(delegation->cred);
+			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);
+			}
+			put_rpccred(cred);
+			if (nfs4_server_rebooted(clp)) {
+				nfs_inode_mark_test_expired_delegation(server,inode);
+				iput(inode);
+				nfs_sb_deactive(server->super);
+				return;
+			}
+			iput(inode);
+			nfs_sb_deactive(server->super);
+			goto restart;
+		}
+	}
+	rcu_read_unlock();
+}
+
+void nfs_inode_find_delegation_state_and_recover(struct inode *inode,
+		const nfs4_stateid *stateid)
+{
+	struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
+	struct nfs_delegation *delegation;
+	bool found = false;
+
+	rcu_read_lock();
+	delegation = rcu_dereference(NFS_I(inode)->delegation);
+	if (delegation &&
+	    nfs4_stateid_match_other(&delegation->stateid, stateid)) {
+		nfs_mark_test_expired_delegation(NFS_SERVER(inode), delegation);
+		found = true;
+	}
+	rcu_read_unlock();
+	if (found)
+		nfs4_schedule_state_manager(clp);
+}
+
 /**
  * nfs_delegations_present - check for existence of delegations
  * @clp: client state handle
@@ -893,7 +1064,7 @@ bool nfs4_copy_delegation_stateid(struct inode *inode, fmode_t flags,
 	flags &= FMODE_READ|FMODE_WRITE;
 	rcu_read_lock();
 	delegation = rcu_dereference(nfsi->delegation);
-	ret = (delegation != NULL && (delegation->type & flags) == flags);
+	ret = nfs4_is_valid_delegation(delegation, flags);
 	if (ret) {
 		nfs4_stateid_copy(dst, &delegation->stateid);
 		nfs_mark_delegation_referenced(delegation);