+int tdb1_chainlock(struct tdb_context *tdb, TDB_DATA key);
+int tdb1_chainunlock(struct tdb_context *tdb, TDB_DATA key);
+int tdb1_chainlock_read(struct tdb_context *tdb, TDB_DATA key);
+int tdb1_chainunlock_read(struct tdb_context *tdb, TDB_DATA key);
+