From a724b4369097897db45d61108c0e976912e586c7 Mon Sep 17 00:00:00 2001
From: Stefan Behrens <sbehrens@giantdisaster.de>
Date: Wed, 11 Sep 2013 09:59:22 +0200
Subject: [PATCH] Btrfs: add the missing mutex unlock in write_all_supers()

The BUG() was replaced by btrfs_error() and return -EIO with the
patch "get rid of one BUG() in write_all_supers()", but the missing
mutex_unlock() was overlooked.

The 0-DAY kernel build service from Intel reported the missing
unlock which was found by the coccinelle tool:

    fs/btrfs/disk-io.c:3422:2-8: preceding lock on line 3374

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
---
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