It makes no sense to report the block stats of a purely metadata-storing
child in query-blockstats. So if the primary child does not have any
data, try to find a unique data-storing child.
Signed-off-by: Max Reitz <mreitz@redhat.com>
---
block/qapi.c | 31 +++++++++++++++++++++++++++++--
1 file changed, 29 insertions(+), 2 deletions(-)
diff --git a/block/qapi.c b/block/qapi.c
index 4807a2b344..c57b42d86d 100644
--- a/block/qapi.c
+++ b/block/qapi.c
@@ -526,6 +526,7 @@ static void bdrv_query_blk_stats(BlockDeviceStats *ds,
BlockBackend *blk)
static BlockStats *bdrv_query_bds_stats(BlockDriverState *bs,
bool blk_level)
{
+ BdrvChild *parent_child;
BlockStats *s = NULL;
s = g_malloc0(sizeof(*s));
@@ -555,9 +556,35 @@ static BlockStats *bdrv_query_bds_stats(BlockDriverState
*bs,
s->has_driver_specific = true;
}
- if (bs->file) {
+ parent_child = bdrv_primary_child(bs);
+ if (!parent_child ||
+ !(parent_child->role & (BDRV_CHILD_DATA | BDRV_CHILD_FILTERED)))
+ {
+ BdrvChild *c;
+
+ /*
+ * Look for a unique data-storing child. We do not need to look for
+ * filtered children, as there would be only one and it would have been
+ * the primary child.
+ */
+ parent_child = NULL;
+ QLIST_FOREACH(c, &bs->children, next) {
+ if (c->role & BDRV_CHILD_DATA) {
+ if (parent_child) {
+ /*
+ * There are multiple data-storing children and we cannot
+ * choose between them.
+ */
+ parent_child = NULL;
+ break;
+ }
+ parent_child = c;
+ }
+ }
+ }
+ if (parent_child) {
s->has_parent = true;
- s->parent = bdrv_query_bds_stats(bs->file->bs, blk_level);
+ s->parent = bdrv_query_bds_stats(parent_child->bs, blk_level);
}
if (blk_level && bs->backing) {