From: Theodore Tso <tytso@mit.edu>
Subject: Re: Possible ext4 corruption - ACL related?
Date: Tue, 10 Mar 2009 20:47:10 -0400
Message-ID: <20090311004709.GC15229@mit.edu>
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Cc: Kevin Shanahan <kmshanah@ucwb.org.au>,
	Eric Sandeen <sandeen@redhat.com>, linux-ext4@vger.kernel.org
To: Andreas Dilger <adilger@sun.com>
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On Tue, Mar 10, 2009 at 06:38:45PM -0600, Andreas Dilger wrote:
> > Actually, it's a bit more complicated than that.  I should really add
> > a hook to debugfs to automate this, but... to find the block to grab,
> > you do this.   
> 
> [many complex steps deleted]
> 
> > So now we know that the block containing inode 867 is 65+54 = 119
> 
> Or you can use imap (which Ted probably wrote in the first place. :-)
> 
> debugfs: imap some/problem/file
> Inode 867 is part of block group 0
> 	located at block 119, offset 0x0180

<Blush>

OK, now I'm embarassed.  I had completely forgotten that I had already
implemented it.  

And to think I've been doing the hard way most of the time (i.e.,
using dc and doing the calculations manually :-)

	     	     	 	  - Ted