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Message-ID: <35fb2e590603032135g19351068veee4e0187dbe629a@mail.gmail.com>
Date: Sat, 4 Mar 2006 05:35:37 +0000
From: "Jon Masters" <jonmasters@gmail.com>
Reply-To: jonathan@jonmasters.org
To: roland <devzero@web.de>
Subject: Re: is there a COW inside the kernel ?
Cc: "Kevin Corry" <kevcorry@us.ibm.com>, linux-kernel@vger.kernel.org,
       "Jeff Dike" <jdike@addtoit.com>, agk@redhat.com,
       jengelh@linux01.gwdg.de
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On 3/3/06, roland <devzero@web.de> wrote:

> i think i will take a closer look on device-mapper, but i'm unsure if it`s
> perfectly suited.

It looks to me that you want to use something more like unionfs with
COW/whiteout mode - there's an implementation based on FUSE available
but I've not really looked at it. Obviously you might just want
something in mainline, in which case you're limited to the FUSE idea
or one of the others already suggested.

> what about merging a cow-dev/file back to the r/o-dev/file ?

This is why I suggest you look at the above.

Jon.