From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gerd Hoffmann <kraxel@redhat.com>
Subject: Re: pv_ops & gntdev?
Date: Wed, 25 Feb 2009 22:45:08 +0100
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To: Jeremy Fitzhardinge <jeremy@goop.org>
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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.

Ok, and that way you'll also get a struct page for the grant mappings,
right?  2.6.18 gntdev does map grants to both kernel and userspace.  Any
 idea why?  Just userspace should be possible too, right?

thanks,
  Gerd