From: Theodore Ts'o <tytso@mit.edu>
Subject: Re: [PATCH v3 0/3] Add XIP support to ext4
Date: Thu, 19 Dec 2013 12:18:48 -0500
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Cc: Dave Chinner <david@fromorbit.com>,
	Matthew Wilcox <matthew.r.wilcox@intel.com>,
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To: Matthew Wilcox <matthew@wil.cx>
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On Thu, Dec 19, 2013 at 10:12:02AM -0700, Matthew Wilcox wrote:
> 
> ... I think it'll actually be ext4_get_block_fault, not _write, and it
> will include code to zero the returned blocks if they're uninitialised.

I assume what you mean here is if we see that the blocks are
uninitialized, we don't need to read from the persistent memory at
all; we can just map in a zeroed page, hopefully one from our stock of
pre-zeroed pages.  Yes?

						- Ted