From mboxrd@z Thu Jan  1 00:00:00 1970
From: Zdenek Kabelac <zkabelac@redhat.com>
Subject: Re: block mapping
Date: Thu, 29 Sep 2011 15:42:59 +0200
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Dne 29.9.2011 15:35, Kasatkin, Dmitry napsal(a):
> Hello All,
> 
> I would like to implement such block device, which can store
> additional information along with the block data.
> For example. so if file system has 4k block, I would like to store
> 4k+256b of additional information...
> 
> Can such block device be implemented with device mapper?
> 

Yes - i.e.the old snapshot target stores the block and it's remapping info
(thought the size info is much smaller then 256b)

Zdenek