Subject: Re: [RFC] Advanced XIP File System
From: David Woodhouse <dwmw2@infradead.org>
To: Josh Boyer <jwboyer@gmail.com>
Cc: Nicolas Pitre <nico@cam.org>, Jared Hulbert <jaredeh@gmail.com>,
       linux-kernel@vger.kernel.org
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Date: Wed, 03 May 2006 13:11:15 +0100
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On Wed, 2006-05-03 at 05:41 -0500, Josh Boyer wrote:
> Yes, I realize that all that is needed is support from other archs.  A
> more general form of the question would be does AXFS depend on
> ARCH_MTD_XIP? 

That's for kernel XIP, which needs special magic for putting certain
functions into RAM instead of the flash, polling for interrupts, etc.

For general _userspace_ XIP we don't necessarily need to do that. We
only need to mark those pages as absent in the page tables if we ever
schedule to userspace while the flash is in a mode other than read mode.
Then handle the page fault by switching the flash back or waiting for
it.

-- 
dwmw2

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