The commit and mirror block nodes are filters, so they should be marked
as such.

Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 block/commit.c | 2 ++
 block/mirror.c | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/block/commit.c b/block/commit.c
index 14788b0708..a95b87bb3a 100644
--- a/block/commit.c
+++ b/block/commit.c
@@ -261,6 +261,8 @@ static BlockDriver bdrv_commit_top = {
     .bdrv_refresh_filename      = bdrv_commit_top_refresh_filename,
     .bdrv_close                 = bdrv_commit_top_close,
     .bdrv_child_perm            = bdrv_commit_top_child_perm,
+
+    .is_filter                  = true,
 };
 
 void commit_start(const char *job_id, BlockDriverState *bs,
diff --git a/block/mirror.c b/block/mirror.c
index b4287a1e2b..5c561c6241 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -1457,6 +1457,8 @@ static BlockDriver bdrv_mirror_top = {
     .bdrv_refresh_filename      = bdrv_mirror_top_refresh_filename,
     .bdrv_close                 = bdrv_mirror_top_close,
     .bdrv_child_perm            = bdrv_mirror_top_child_perm,
+
+    .is_filter                  = true,
 };
 
 static void mirror_start_job(const char *job_id, BlockDriverState *bs,
-- 
2.17.1