From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cn.fujitsu.com ([222.73.24.84]:36408 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1750987Ab2LSLZK (ORCPT ); Wed, 19 Dec 2012 06:25:10 -0500 Message-ID: <50D1A430.607@cn.fujitsu.com> Date: Wed, 19 Dec 2012 19:25:36 +0800 From: Miao Xie Reply-To: miaox@cn.fujitsu.com MIME-Version: 1.0 To: Linux Btrfs CC: Arne Jansen , wangshilong Subject: About btrfs qgroup import/export command References: <50D1632E.6010801@cn.fujitsu.com> In-Reply-To: <50D1632E.6010801@cn.fujitsu.com> Content-Type: text/plain; charset=UTF-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: Hi, everyone. As we know, there is no backup function for qgroup. when the problem occurs, the users must recover qgroup configuration manually, it is not convenient. And besides that, some users might want to import an existed qgroup configuration into a new filesystem. Btrfs does not have such a function,it can only be done manually. So we want to implement btrfs qgroup import/export commands. 1)'btrfs qgroup export' commands will export qgroup tree into a user's specified file.(stdout by default) 2)user may modify the configuration file firstly and then import it into the filesystem.(by 'btrfs qgroup import' command) The file may be formated as the following: Qgroupid is_compressed is_exclusive limited_size parent ---------------------------------------------------------------------- 0/1 0 0 10G 1/0 1/0 1 1 20G --- If 'is_exclusive' is set, 'limited_size' corresponds to max exlusive size, else max referenced size. Here 'parent' exclude ancestral qgroups. Is there any comment about this idea? Thanks Miao