+ return write_header(tdb);
+
+fail_release:
+ tdb_access_release(tdb, oldf);
+ return -1;
+}
+
+/* Expand the database. */
+int tdb_expand(struct tdb_context *tdb, tdb_len_t klen, tdb_len_t dlen,
+ bool growing)
+{
+ uint64_t new_num_buckets, new_num_zones, new_zone_bits;
+ uint64_t old_num_zones, old_size, old_zone_bits;
+ tdb_len_t add, needed;
+
+ /* We need room for the record header too. */
+ needed = sizeof(struct tdb_used_record)
+ + adjust_size(klen, dlen, growing);
+
+ /* tdb_allrecord_lock will update header; did zones change? */
+ old_zone_bits = tdb->header.v.zone_bits;
+ old_num_zones = tdb->header.v.num_zones;
+
+ /* FIXME: this is overkill. An expand lock? */
+ if (tdb_allrecord_lock(tdb, F_WRLCK, TDB_LOCK_WAIT, false) == -1)
+ return -1;
+
+ /* Someone may have expanded for us. */
+ if (old_zone_bits != tdb->header.v.zone_bits
+ || old_num_zones != tdb->header.v.num_zones)
+ goto success;
+
+ /* They may have also expanded the underlying size (otherwise we'd
+ * have expanded our mmap to look at those offsets already). */
+ old_size = tdb->map_size;
+ tdb->methods->oob(tdb, tdb->map_size + 1, true);
+ if (tdb->map_size != old_size)
+ goto success;
+
+ add = expand_to_fill_zones(tdb);
+ if (add == TDB_OFF_ERR)