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From: Kumar Gala <galak@kernel.crashing.org>
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Subject: Re: [PATCH] powerpc/mm: Implement _PAGE_SPECIAL & pte_special() for
	32-bit
Date: Thu, 31 Jul 2008 13:50:28 -0500
References: <Pine.LNX.4.64.0807311345380.8012@blarg.am.freescale.net>
Cc: Nick Piggin <npiggin@suse.de>, linuxppc-dev list <linuxppc-dev@ozlabs.org>,
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On Jul 31, 2008, at 1:48 PM, Kumar Gala wrote:

> Implement _PAGE_SPECIAL and pte_special() for 32-bit powerpc. This  
> bit will
> be used by the fast get_user_pages() to differenciate PTEs that  
> correspond
> to a valid struct page from special mappings that don't such as IO  
> mappings
> obtained via io_remap_pfn_ranges().
>
> We currently only implement this on sub-arch that support SMP or  
> will so
> in the future (6xx, 44x, FSL-BookE) and not (8xx, 40x).
>
> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
> ---
> Nick, do you forsee using _PAGE_SPECIAL for other applications that  
> would
> be of interested to non-SMP hw?
>
> We can look at adding it into 8xx and 40x, but was being lazy as I  
> assume
> there is no point.
>
> - k

Josh,

Can you test this on 44x for me.

thanks

- k