DD_USED_CHILD
return (dsl_dir_phys(dd)->dd_used_breakdown[DD_USED_CHILD] +
dsl_dir_diduse_space(dd->dd_parent, DD_USED_CHILD,
DD_USED_CHILD_RSRV, DD_USED_CHILD, tx);
dsl_dir_diduse_space(dd->dd_parent, DD_USED_CHILD,
dsl_dir_diduse_space(newparent, DD_USED_CHILD,