From: Neil Brown <neilb@suse.de>
Subject: Re: [EXT4 set 4][PATCH 1/5] i_version:64 bit inode version
Date: Wed, 11 Jul 2007 15:05:27 +1000
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Cc: Andrew Morton <akpm@linux-foundation.org>,
	linux-fsdevel@vger.kernel.org, nfsv4@linux-nfs.org,
	linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org
To: cmm@us.ibm.com
In-Reply-To: message from Neil Brown on Wednesday July 11
Sender: linux-ext4-owner@vger.kernel.org


It just occurred to me:

 If i_version is 64bit, then knfsd would need to be careful when
 reading it on a 32bit host.  What are the locking rules?

 Presumably it is only updated under i_mutex protection, but having to
 get i_mutex to read it would seem a little heavy handed.

 Should it use a seqlock like i_size?
 Could we use the same seqlock that i_size uses, or would we need a
 separate one?

NeilBrown