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) {