block/dirty-bitmap: refactor bdrv_dirty_bitmap_next

bdrv_dirty_bitmap_next is always used in same pattern. So, split it
into _next and _first, instead of combining two functions into one and
add FOR_EACH_DIRTY_BITMAP macro.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190916141911.5255-5-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>

1 files changed, 1 insertions, 3 deletions

diff --git a/block.c b/block.c
index d19a4781a3..5721441697 100644
--- a/block.c
+++ b/block.c
@@ -5390,9 +5390,7 @@ static void coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
         }
     }
 
-    for (bm = bdrv_dirty_bitmap_next(bs, NULL); bm;
-         bm = bdrv_dirty_bitmap_next(bs, bm))
-    {
+    FOR_EACH_DIRTY_BITMAP(bs, bm) {
         bdrv_dirty_bitmap_skip_store(bm, false);
     }