[Qemu-block] [PATCH v4 01/11] block: Mark commit and mirror as filter drivers

[Max Reitz]

The commit and mirror block nodes are filters, so they should be marked
as such.  (Strictly speaking, BDS.is_filter's documentation states that
a filter's child must be bs->file.  The following patch will relax this
restriction, however.)

Signed-off-by: Max Reitz <address@hidden>
Reviewed-by: Alberto Garcia <address@hidden>
Reviewed-by: Eric Blake <address@hidden>
---
 block/commit.c | 2 ++
 block/mirror.c | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/block/commit.c b/block/commit.c
index ba60fef58a..02eab34925 100644
--- a/block/commit.c
+++ b/block/commit.c
@@ -257,6 +257,8 @@ static BlockDriver bdrv_commit_top = {
     .bdrv_co_block_status       = bdrv_co_block_status_from_backing,
     .bdrv_refresh_filename      = bdrv_commit_top_refresh_filename,
     .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 ff15cfb197..8b2404051f 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -1489,6 +1489,8 @@ static BlockDriver bdrv_mirror_top = {
     .bdrv_co_block_status       = bdrv_co_block_status_from_backing,
     .bdrv_refresh_filename      = bdrv_mirror_top_refresh_filename,
     .bdrv_child_perm            = bdrv_mirror_top_child_perm,
+
+    .is_filter                  = true,
 };
 
 static void mirror_start_job(const char *job_id, BlockDriverState *bs,
-- 
2.20.1