From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Landley Subject: Re: [PATCH 00/13] overlay filesystem: request for inclusion (v16) Date: Fri, 22 Mar 2013 00:15:48 -0500 Message-ID: <1363929348.15703.58@driftwood> References: <20130320194108.24192.qmail@science.horizon.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; DelSp=Yes; Format=Flowed Content-Transfer-Encoding: 8BIT Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, miklos@szeredi.hu, viro@ZenIV.linux.org.uk, linux@horizon.com To: George Spelvin Return-path: In-Reply-To: <20130320194108.24192.qmail@science.horizon.com> (from linux@horizon.com on Wed Mar 20 14:41:08 2013) Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On 03/20/2013 02:41:08 PM, George Spelvin wrote: > Sorry for being so very late to the party, but rather than messing > with xattrs, why not just have a specific file (say, default > /.whiteout, > but selectable via a mount option) and links to it are counted as > whiteout entries? Don't the ext2 descendants have an array of reserved inodes at the beginning (one of which is the journal for ext3, most of which were still unused last I checked)? Maybe ext4 optimized this away, but that would mean it doesn't have to be anywhere in the namespace. (Of course you'd have to teach fsck about it, and probably not update the link count or you'll have contention and integer overflow...) Rob