Replace the way we use mutex in parallels_co_check() for simplier
and less error prone code.

Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
---
 block/parallels.c | 33 ++++++++++++++-------------------
 1 file changed, 14 insertions(+), 19 deletions(-)

diff --git a/block/parallels.c b/block/parallels.c
index 3c38a0fd09..61e7e4010d 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -560,30 +560,25 @@ static int coroutine_fn parallels_co_check(BlockDriverState *bs,
     BDRVParallelsState *s = bs->opaque;
     int ret;
 
-    qemu_co_mutex_lock(&s->lock);
+    WITH_QEMU_LOCK_GUARD(&s->lock) {
+        parallels_check_unclean(bs, res, fix);
 
-    parallels_check_unclean(bs, res, fix);
+        ret = parallels_check_outside_image(bs, res, fix);
+        if (ret < 0) {
+            return ret;
+        }
 
-    ret = parallels_check_outside_image(bs, res, fix);
-    if (ret < 0) {
-        goto out;
-    }
+        ret = parallels_check_leak(bs, res, fix);
+        if (ret < 0) {
+            return ret;
+        }
 
-    ret = parallels_check_leak(bs, res, fix);
-    if (ret < 0) {
-        goto out;
+        parallels_collect_statistics(bs, res, fix);
     }
 
-    parallels_collect_statistics(bs, res, fix);
-
-out:
-    qemu_co_mutex_unlock(&s->lock);
-
-    if (ret == 0) {
-        ret = bdrv_co_flush(bs);
-        if (ret < 0) {
-            res->check_errors++;
-        }
+    ret = bdrv_co_flush(bs);
+    if (ret < 0) {
+        res->check_errors++;
     }
 
     return ret;
-- 
2.34.1