From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932651Ab0KWA5I (ORCPT ); Mon, 22 Nov 2010 19:57:08 -0500 Received: from kroah.org ([198.145.64.141]:45014 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932443Ab0KWA5G (ORCPT ); Mon, 22 Nov 2010 19:57:06 -0500 Date: Mon, 22 Nov 2010 16:56:56 -0800 From: Greg KH To: Sage Weil Cc: Yehuda Sadeh , ceph-devel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] rbd: replace the rbd sysfs interface Message-ID: <20101123005656.GA29289@kroah.com> References: <1289953929-30896-1-git-send-email-yehuda@hq.newdream.net> <20101117171924.GC12050@kroah.com> <20101118013002.GC8558@kroah.com> <20101119020820.GB18767@kroah.com> <1290468787.1792.63.camel@yehudasa-desktop> <20101123001439.GB31294@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 22, 2010 at 04:45:31PM -0800, Sage Weil wrote: > Hi Greg, > > On Mon, 22 Nov 2010, Greg KH wrote: > > On Mon, Nov 22, 2010 at 03:33:07PM -0800, Yehuda Sadeh wrote: > > > > > > > > > On Fri, Nov 19, 2010 at 12:42 PM, Yehuda Sadeh Weinraub wrote: > > > > One solution would be to create kobjects for (3) and for (4), without > > > > using a group name. Another way, we can create groups for (2), and (3) > > > > under (1), but that's about it, you can't create the snap specific > > > > directory this way without resorting to some internal sysfs directory > > > > creation, which will be horribly wrong. At that point we don't have > > > > anything for 'snaps', and we don't really need to do any operations > > > > under that directory, we just need it to exist so that it contains the > > > > snapshot-specific directories. > > > > > > > > Another way would be to create a group for (2) under (1) and create a > > > > kobject for (3), for which you can create group per snapshot. > > > > > > > > Am I missing something? We already have the first solution (kobjects > > > > only) implemented, is there some real benefit for using the third > > > > method? We'll have to manually add remove groups anyway, as snapshots > > > > can be removed and new snapshots can be added. > > > > > > > > > > And following is the implementation for the first solution. It has a device > > > for the rbd_dev, a kobject for the top snapshot directory and a kobject per > > > snapshot. Please let me know if there's any issue with this implementation. > > > We'd like to get this fixed for 2.6.37 and considering the large patch, > > > it'd be nice getting an ack for it. > > > > It's way too late for .37, as this is new stuff, right? > > Well, that's the problem. The current sysfs interface was based on > osdblk's. That part didn't come up during review, and I wasn't aware that > the sysfs interface should get an explicit ack from you. After RBD was > merged in 2.6.37-rc1 I saw part of the SCST sysfs thread and realized the > current interface was problematic, and we've been trying to work out how > to fix it ever since. > > As things stand, we can either > 1- wait, get an osdblk-like interface in 2.6.37, and change it later (a > big fat no-no, as I understand things!) > 2- get an improved sysfs interface sorted out and push to Linus ASAP (my > preference) > 3- have Linus revert RBD altogether :( > > I'm hoping for #2, but we may need a bit more help from you unfortunately! How about: 4- make the code depend on CONFIG_BROKEN and get it working for .38? thanks, greg k-h