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 22:43:26 +0100
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To: Jeremy Fitzhardinge <jeremy@goop.org>
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Jeremy Fitzhardinge wrote:
> Gerd Hoffmann wrote:
>> Jeremy Fitzhardinge wrote:
>>  
>>> Hm, I hope not.  Doesn't it always end up using set_pte*?
>>>     
>>
>> ptep_get_and_clear_full();
>>
>> See zap_pte_range() in mm/memory.c
> 
> Ah, right.  It could be changed to use ptep_modify_prot_start/commit. 
> That would make it batchable too.  Slightly less good for native.

Hmm.  One more Q:  How is pinning used?  Is a process pinned all the
time?  Or can it happen that the pages are unpinned in case it does hang
around idle for a while?  Is there some way to prevent a process from
being unpinned?

I somehow feel like checking out mmu notifiers first ...

thanks,
  Gerd