From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Niraj kumar" <niraj17@gmail.com>
Subject: btrfs: Problem with multi device mounting
Date: Sun, 7 Dec 2008 23:05:07 +0530
Message-ID: <b82a89170812070935p36a2285ft30d475198206f89f@mail.gmail.com>
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To: linux-btrfs@vger.kernel.org
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Hi,

This problem happens when mkfs.btrfs has been executed while
btrfs module was not loaded into the kernel.

I am using the latest commit on btrfs-unstable.
Commit:
c99e905c945c462085c6d64646dc5af0c0a16815

Steps to reproduce:

1) Create a btrfs filesystem while the btrfs module is not yet loaded.

[root@f10-vm1 ~]# uname -a
Linux f10-vm1 2.6.28-rc5 #9 SMP Thu Dec 4 18:09:37 IST 2008 i686 i686
i386 GNU/Linux
[root@f10-vm1 ~]# rmmod btrfs

[root@f10-vm1 ~]# /home/niraj/btrfs/bin/mkfs.btrfs /dev/sdb1 /dev/sdb2
adding device /dev/sdb2 id 2
fs created label (null) on /dev/sdb1
	nodesize 4096 leafsize 4096 sectorsize 4096 size 4.00GB
Btrfs v0.16-25-gd45ee76

2) Try to mount it (this automatically loads btrfs module) :

[root@f10-vm1 ~]# mount -t btrfs /dev/sdb1 /f1
mount: wrong fs type, bad option, bad superblock on /dev/sdb1,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so


Here is the relevant dmesg output:
Btrfs loaded
device fsid 514ee5004d4b722d-ae7cc1f744a0b49f devid 1 transid 9 /dev/sdb1
btrfs: failed to read the system array on sdb1
btrfs: open_ctree failed


Let me know if I can provide more information.


-Niraj