From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: pv_ops & gntdev?
Date: Wed, 25 Feb 2009 14:30:32 -0800
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To: Gerd Hoffmann <kraxel@redhat.com>
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Gerd Hoffmann wrote:
> Jeremy Fitzhardinge wrote:
>   
>> Gerd Hoffmann wrote:
>>     
>>> Also: 2.6.18 gntdev does some funky interaction with the balloon driver.
>>>  What is the point in doing so?
>>>   
>>>       
>> Oh, the alloc_empty_pages_and_pagevec() stuff?  It allocates some pages,
>> just for their pfn slots, and then returns the underlying memory back to
>> Xen.  It uses the pfns to slot granted pages into.
>>     
>
> Yep, gives pfn slot for the grant map.  And a struct page too.
>
> /me wonderes whenever that is required or whenever I could just map the
> grants without asking the balloon driver for some slots ...
>   

I think they could be special ptes now, and not need any struct page.

    J