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Subject: Re: [rfc] split_page function to split higher order pages?
From: Arjan van de Ven <arjan@infradead.org>
To: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Nick Piggin <npiggin@suse.de>,
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Date: Mon, 23 Jan 2006 09:54:05 +0100
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On Mon, 2006-01-23 at 09:47 +0100, Heiko Carstens wrote:
> > > > Just wondering what people think of the idea of using a helper
> > > > function to split higher order pages instead of doing it manually?
> > > 
> > > Maybe it's worth documenting that this is for kernel (or even
> > > architecture) internal use only and that drivers really shouldn't be
> > > doing this..
> > 
> > I guess it doesn't seem like something drivers would need to use
> > (and none appear to do anything like it).
> 
> And I thought this could/should be used together with vm_insert_page() that
> drivers are supposed to use nowadays instead of remap_pfn_range().
> Why shouldn't drivers use this?

because in that case the drivers shouldn't allocate higher order pages
in the first place...