From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: Adding subroot information to /proc/mounts, or obtaining that through other means Date: Wed, 20 Jun 2007 14:20:49 -0700 Message-ID: <46799A31.10301@zytor.com> References: <467994BD.6000403@zytor.com> <20070620210343.GQ21478@ftp.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Linux Kernel Mailing List , linux-fsdevel@vger.kernel.org, util-linux-ng@vger.kernel.org To: Al Viro , Ram Pai Return-path: Received: from terminus.zytor.com ([192.83.249.54]:46447 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751569AbXFTVYd (ORCPT ); Wed, 20 Jun 2007 17:24:33 -0400 In-Reply-To: <20070620210343.GQ21478@ftp.linux.org.uk> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org Al Viro wrote: > On Wed, Jun 20, 2007 at 01:57:33PM -0700, H. Peter Anvin wrote: >> ... or, alternatively, add a subfield to the first field (which would >> entail escaping whatever separator we choose): >> >> /dev/md6 /export ext3 rw,data=ordered 0 0 >> /dev/md6:/users/foo /home/foo ext3 rw,data=ordered 0 0 >> /dev/md6:/users/bar /home/bar ext3 rw,data=ordered 0 0 > > Hell, no. The first field is in principle impossible to parse unless > you know the fs type. > > How about making a new file with sane format? From the very > beginning. E.g. mountpoint + ID + relative path + type + options, > where ID uniquely identifies superblock (e.g. numeric st_dev) > and backing device (if any) is sitting among the options... Okay, I see there has been some discussion on this earlier, based on a proposal by Ram Pai, so it pretty much comes down to redesigning this right. I see some issues with his proposal (device numbers exported to userspace in text form should be separated into major:minor form, for one thing.) I know the util-linux-ng people have also had issues with /proc/mounts that they would like resolved in order to finally nuke /etc/mtab. Is Ram still working on this? I'd like to help make this happen so we can be done with it. -hpa