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Subject: Re: Zeroing data blocks
From: Arjan van de Ven <arjan@infradead.org>
To: Avinash Ramanath <avinashr@gmail.com>
Cc: kernelnewbies@nl.linux.org, linux-kernel@vger.kernel.org
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Date: Sat, 05 Aug 2006 19:42:22 +0200
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On Sat, 2006-08-05 at 10:13 -0700, Avinash Ramanath wrote:
> Hi,
> 
> I want to do this at the filesystem-level not in user-space.
> I have a stackable-filesystem that runs as a layer on top of the
> existing filesystem (with all the function pointers mapped to the
> corresponding base filesystem function pointers, and other suitable
> adjustments).
> So yes I have access to the filesystem.
> But the question is how can I access those particular data-blocks?

I think you misunderstood: You need to do this in the filesystem layer
that allocates and tracks the blocks. You really can't do it outside
that...