qa: kernel.sh: unlock before rolling back

"rbd snap rollback" expects an unlocked image, but we may get there
locked if object map is enabled (or if lock_on_read is specified in
rbd_default_map_options).

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit 3aae140353a4b27dfe6e2d2ac7a49cdcdbbe5ffe)

diff --git a/qa/workunits/rbd/kernel.sh b/qa/workunits/rbd/kernel.sh
index 4c15983d4b3a25b13ee2c751e029ce2197ada4d8..faa5760eed83d5c0bd44c47e9752ea8b06da77ce 100755 (executable)
--- a/qa/workunits/rbd/kernel.sh
+++ b/qa/workunits/rbd/kernel.sh
@@ -77,6 +77,10 @@ cp /tmp/img1 /tmp/img1.trunc
 truncate -s 41943040 /tmp/img1.trunc
 cmp /tmp/img1.trunc /tmp/img1.small
 
+# rollback expects an unlocked image
+# (acquire and) release the lock as a side effect
+rbd bench --io-type read --io-size 1 --io-threads 1 --io-total 1 testimg1
+
 # rollback and check data again
 rbd snap rollback --snap=snap1 testimg1
 cat /sys/bus/rbd/devices/$DEV_ID1/size | grep 76800000