From mboxrd@z Thu Jan 1 00:00:00 1970 From: Theodore Ts'o Subject: Re: [PATCH 2/3] ext4: Implement subtree ID support for ext4 filesystem Date: Wed, 11 Jul 2012 09:24:29 -0400 Message-ID: <20120711132429.GA10872@thunk.org> References: <1341847725-26114-1-git-send-email-dmonakhov@openvz.org> <1341847725-26114-3-git-send-email-dmonakhov@openvz.org> <20120709210439.GB11960@thunk.org> <874npefo7n.fsf@dmbot.sw.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, jack@suse.cz To: Dmitry Monakhov Return-path: Content-Disposition: inline In-Reply-To: <874npefo7n.fsf@dmbot.sw.ru> Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Wed, Jul 11, 2012 at 04:59:24PM +0400, Dmitry Monakhov wrote: > > May be it would be better if i describe feature as "Namespace ID" > namespaces is well known abstraction in kernel, so misunderstanding > shouldn't happen. What if we call it a "quota group", with the rules that if a parent directory has a quota group, any files or directories created in that parent directory will inherit that quota group, and only processes with CAP_SYS_ADMIN can change it. And then what if we simply make the rule that if an inode has a quota group, the quota is charged against two group id's; the group id named in inode, and the quota group? That is, do we really need to have a separate namespace for group ids and "subtrees" or "namespaces"? That means we don't have to change the userspace quota tools and we can leverage the existing ways people are used to managing group quotas. - Ted