From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-36-i2.italiaonline.it ([212.48.25.210]:36684 "EHLO smtp-36.italiaonline.it" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932455AbaLDR6b (ORCPT ); Thu, 4 Dec 2014 12:58:31 -0500 Message-ID: <5480A0C3.5050708@inwind.it> Date: Thu, 04 Dec 2014 18:58:27 +0100 From: Goffredo Baroncelli Reply-To: kreijack@inwind.it MIME-Version: 1.0 To: Anand Jain 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> In-Reply-To: <547FC24A.9000107@oracle.com> Content-Type: text/plain; charset=utf-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: 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. 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 > > [...] -- gpg @keyserver.linux.it: Goffredo Baroncelli Key fingerprint BBF5 1610 0B64 DAC6 5F7D 17B2 0EDA 9B37 8B82 E0B5