[Qemu-block] [Patch v12 resend 02/10] Store parent BDS in BdrvChild

[Wen Congyang]

We need to access the parent BDS to get the root BDS.

Signed-off-by: Wen Congyang <address@hidden>
Signed-off-by: zhanghailiang <address@hidden>
Signed-off-by: Gonglei <address@hidden>
---
 block.c                   | 1 +
 include/block/block_int.h | 1 +
 2 files changed, 2 insertions(+)

diff --git a/block.c b/block.c
index eaf479a..0a0468f 100644
--- a/block.c
+++ b/block.c
@@ -1204,6 +1204,7 @@ BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs,
     BdrvChild *child = g_new(BdrvChild, 1);
     *child = (BdrvChild) {
         .bs     = child_bs,
+        .parent = parent_bs,
         .name   = g_strdup(child_name),
         .role   = child_role,
     };
diff --git a/include/block/block_int.h b/include/block/block_int.h
index ea20d12..1f56046 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -357,6 +357,7 @@ extern const BdrvChildRole child_format;
 
 struct BdrvChild {
     BlockDriverState *bs;
+    BlockDriverState *parent;
     char *name;
     const BdrvChildRole *role;
     QLIST_ENTRY(BdrvChild) next;
-- 
2.5.0