From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josef Bacik Subject: Re: [PATCH] fs: make i_generation a u64 Date: Thu, 12 Apr 2012 15:49:56 -0400 Message-ID: <20120412194955.GO1924@localhost.localdomain> References: <1334176968-8687-1-git-send-email-josef@redhat.com> <20120412194217.GC26332@thunk.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Josef Bacik , linux-fsdevel@vger.kernel.org, linux-btrfs@vger.kernel.org, viro@ZenIV.linux.org.uk To: "Ted Ts'o" Return-path: Received: from mx1.redhat.com ([209.132.183.28]:50934 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757150Ab2DLTuE (ORCPT ); Thu, 12 Apr 2012 15:50:04 -0400 Content-Disposition: inline In-Reply-To: <20120412194217.GC26332@thunk.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Thu, Apr 12, 2012 at 03:42:17PM -0400, Ted Ts'o wrote: > On Wed, Apr 11, 2012 at 04:42:48PM -0400, Josef Bacik wrote: > > Btrfs stores generation numbers as 64bit numbers, which means we have to > > carry around a u64 in our incore inode in addition to setting i_generation. > > So convert to a u64 so btrfs can kill it's incore generation. Thanks, > > > > Signed-off-by: Josef Bacik > > Why is btrfs using a 64-bit generation number, out of curiosity? The > only user of the inode generation number as far as I can tell is NFS, > and even NFSv4 is using a 32-bit generation number.... > It's just tied to our transaction id #'s which are 64bit, no super awesome reason or anything. Thanks, Josef