From mboxrd@z Thu Jan  1 00:00:00 1970
From: Carsten Otte <cotte@freenet.de>
Subject: Re: [RFC/PATCH 2/4] fs/mm: execute in place (3rd version)
Date: Tue, 24 May 2005 19:01:21 +0200
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Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	schwidefsky@de.ibm.com, akpm@osdl.org,
	Christoph Hellwig <hch@infradead.org>
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To: suparna@in.ibm.com
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Suparna Bhattacharya wrote:

> OK, though this leaves filemap.c alone which is good, I have to admit
>
>that this entire duplication of read/write routines really worries me.
>
>There has to be a third way.
>  
>
Just thinking loud here:
When looking at patch v2, the read split is done in do_generic_mapping_read
vs do_xip_mapping read. In the write path, the split is at
generic_file_xip_write,
generic_file_buffered_write and generic_file_direct_write.
How about abstracting on that interface? Like make those become address
space operations. This way, the filesystems could select the corresponding
function. No need to distinguish between xip, direct_IO, and classic
readpage/writepage in the generic code anymore.
Would this go in the direction you're thinking Suparna? Is it worth a
try to see
how it comes out? Opinions anyone?

cheers,
Carsten