From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kara Subject: Re: [PATCH 1/3] quota: Add a new quotactl command Q_XGETQSTATV Date: Wed, 21 Aug 2013 15:01:52 +0200 Message-ID: <20130821130152.GA9709@quack.suse.cz> References: <1375828029-26360-1-git-send-email-sekharan@us.ibm.com> <1375828029-26360-2-git-send-email-sekharan@us.ibm.com> <20130821064357.GA8822@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Chandra Seetharaman , xfs@oss.sgi.com, linux-fsdevel , Steven Whitehouse , Jan Kara , Abhijith Das To: Christoph Hellwig Return-path: Received: from cantor2.suse.de ([195.135.220.15]:41484 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751509Ab3HUNCD (ORCPT ); Wed, 21 Aug 2013 09:02:03 -0400 Content-Disposition: inline In-Reply-To: <20130821064357.GA8822@infradead.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Tue 20-08-13 23:43:57, Christoph Hellwig wrote: > Sorry for being late to the game, but I don not like the in-kernel > interface here at all. Given that Q_XGETQSTATV is a strict superset > of Q_XGETQSTAT there is no need for the second method - just always > fill out the larger in-kernel structure and only copy the smaller > information to userspace for the Q_XGETSTAT case. That keeps the amount > of code required in the implementations of the methods low and follows > the model used elsewhere in the kernel (e.g. stat and statfs) Well, the trouble is with gquota vs pquota - previously we report in qs_gquota field either group quotas or project quotas depending on what is turned on. Generic quota code doesn't know this so xfs get_xstatev() would have to recognize whether it is being called from the old Q_XGETSTAT quotactl or from the new Q_XGETSTATV quotactl to know where to fill in project quotas. And at that point you somewhat loose the elegancy of using one interface - we could set qs_version to some special value so that .get_xstatev() recognizes this and does the magic but that doesn't seem very different from the extra call... Some duplication could be certainly avoided within XFS itself. Honza -- Jan Kara SUSE Labs, CR