From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:24404 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932378AbaLEDON (ORCPT ); Thu, 4 Dec 2014 22:14:13 -0500 Message-ID: <54812391.3090505@oracle.com> Date: Fri, 05 Dec 2014 11:16:33 +0800 From: Anand Jain MIME-Version: 1.0 To: kreijack@inwind.it CC: Goffredo Baroncelli , linux-btrfs , David Sterba , Zygo Blaxell Subject: Re: [RFC][PATCH v2] mount.btrfs helper References: <547B5724.1060507@libero.it> <547FC24A.9000107@oracle.com> <5480A0C3.5050708@inwind.it> In-Reply-To: <5480A0C3.5050708@inwind.it> Content-Type: text/plain; charset=UTF-8; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 05/12/2014 01:58, Goffredo Baroncelli wrote: > On 12/04/2014 03:09 AM, Anand Jain wrote: >> >> >> On 01/12/2014 01:43, Goffredo Baroncelli wrote: >>> Hi all, >>> >>> this patch provides a "mount.btrfs" helper for the mount command. A >>> btrfs filesystem could span several disks. This helper scans all >>> the partitions to discover all the disks required to mount a >>> filesystem. So it would not necessary any-more to "scan" the >>> partitions to mount a filesystem. >>> >>> mount.btrfs passes in the option parameters the devices required to >>> mount a filesystem. Supposing that a filesystem is composed by >>> several disks (/dev/sd[cdef]), when the user runs "mount /dev/sdd >>> /mnt", mount.btrfs is called and it executes the the mount(2) >>> syscall as below: >>> >>> mount("/dev/sdd", "/mnt", "btrfs", 0, "device=/dev/sdc,device=/dev/sde,device=/de/vsdf"). >> >> >> in linux its bit messy that there are different name/paths to the >> same device, its the way it is. So btrfs-progs normalizes these paths >> to "a" thing and provide it to the kernel during btrfs dev scan. >> since device path normalization is done at the user space level not >> in the kernel, the device paths sent using mount option would miss >> this part. > > Good point. I have to normalize the path. I put this in my todo list. for normalization to be effective in the long term it has to be at a single common place, kernel ? Jeff Mahoney seems to agree as well.. follow ups of this patch.. may help. [PATCH] btrfs-progs: canonicalize pathnames for device commands Thanks, Anand > What I am not sure is the case when the user passes the devices via > device=.... options explicitly. > In this case I prefer to leave these as are... The (super user) know what > he is doing.... > >> >> -Anand >> >> > [...] > >