No built-in methods can be used to find the component's parent object. To get the datagrid object from a linkbutton, you will have to get the pagination object then datagrid object.
var btn = $('#btn'); // the linkbutton in pagination
var pg = btn.closest('div.pagination'); // get the pagination object
var dg = pg.prevAll('div.datagrid-view:first').children('table'); // get the datagrid object
dg.datagrid('...'); // call some methods