From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cantor2.suse.de ([195.135.220.15]:36381 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932118Ab3IPLwN (ORCPT ); Mon, 16 Sep 2013 07:52:13 -0400 Date: Mon, 16 Sep 2013 13:52:07 +0200 From: David Sterba To: Liu Bo Cc: linux-btrfs@vger.kernel.org, jeff.liu@oracle.com Subject: Re: [PATCH v3] Btrfs: export btrfs space shared info to userspace Message-ID: <20130916115207.GS6810@suse.cz> Reply-To: dsterba@suse.cz References: <1379323965-21693-1-git-send-email-bo.li.liu@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1379323965-21693-1-git-send-email-bo.li.liu@oracle.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Mon, Sep 16, 2013 at 05:32:45PM +0800, Liu Bo wrote: > Similar to ocfs2, btrfs also supports that extents can be shared by > different inodes, and there are some userspace tools requesting > for this kind of 'space shared infomation'.[1] > > ocfs2 uses flag FIEMAP_EXTENT_SHARED, so does btrfs. > > [1]: http://thr3ads.net/ocfs2-devel/2010/09/489052-PATCH-3-3-shared-du-using-fiemap-to-figure-up-the-shared-extents-per-file-and-the-footprint-in > > Signed-off-by: Liu Bo Reviewed-by: David Sterba