+ /*
+ * If verify_backlog is enabled, we'll run the verify in this
+ * handler as well. For that case, we may need up to twice the
+ * amount of bytes.
+ */
+ total_bytes = td->o.size;
+ if (td->o.verify != VERIFY_NONE &&
+ (td_write(td) && td->o.verify_backlog))
+ total_bytes += td->o.size;
+