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Date: Tue, 15 Nov 2005 17:15:58 -0600
From: "Christopher Friesen" <cfriesen@nortel.com>
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To: Arnd Bergmann <arnd@arndb.de>
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Cc: linuxppc64-dev@ozlabs.org, linuxppc-embedded@ozlabs.org
Subject: Re: modify the cache-inhibit and guard bits from userspace?
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Arnd Bergmann wrote:

> I have seen an earlier patch that modifies madvise to do this, which seems
> a little saner than mprotect, although they can probably both be implemented
> in a similar way.

Ah, that would make sense.  It does fit the intent of the function a bit 
better.

> Alternatively, you could write a new file system similar to hugetlbfs and set 
> the cache-inhibit bit in its mmap function.

Also a possibility.  I think the madvise method is a bit cleaner for the 
apps.

Chris