[sheepdog] [PATCH] fix functional test script to detach loop device

[Robin Dong]

From: Robin Dong <sanbai at taobao.com>

When I run test case 054 and 057, there will be error like:

	057 Last Used:11s.  Test md hot-plug and hot-unplug - output mismatch (see 057.out.bad)
	--- 057.out	2013-11-20 11:04:05.405938952 +0800
	+++ 057.out.bad	2013-12-16 14:54:07.045241449 +0800
	@@ -1,30 +1,33 @@
	 QA output created by 057
	 +mount: could not find any free loop device
	 +mount: could not find any free loop device
	 +mount: could not find any free loop device
	  using backend plain store

The reason is _cleanup_devices only umount but not detach loop devices. So
I add these detach operations.

Signed-off-by: Robin Dong <sanbai at taobao.com>
---
 tests/functional/common.rc | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tests/functional/common.rc b/tests/functional/common.rc
index eadedf7..221d760 100644
--- a/tests/functional/common.rc
+++ b/tests/functional/common.rc
@@ -402,6 +402,10 @@ _cleanup_devices()
         umount -l $d
         rm -f $d.img
     done
+
+    for d in `find /dev/ -name "loop*"`; do
+        losetup -d $d &> /dev/null
+    done
 }
 
 _list_data_obj()
-- 
1.7.12.4