Redirect from embedded controller

I use embedded controller to render form that's used on multiple pages:

Twig

{% render 'Bundle:Controller:someForm' %}

Controller

public function someFormAction()
{
    // Some logic

    ...

    if ($form->isValid()) {

        ...

        $this->get('session')->setFlash('successful', "Woey!");

        return $this->redirect($this->generateUrl('homepage'));
    }

    return $this->render('Bundle:Template:form.html.twig', array('form' => $form->createView()));
}

I need to redirect back to homepage after the form was successfully submitted as a part of post-redirect-get design pattern. If I use it as I described above, I'll get exception as response from embedded controller was 302 instead of 200 (at least I expect it works like this).

Is it possible to redirect normally in such scenario? Or am I approaching the situation (with form that's rendered on multiple pages) from totally wrong angle?