const BdrvChildRole *child_role);
void bdrv_root_unref_child(BdrvChild *child);
-void blk_set_bs(BlockBackend *blk, BlockDriverState *bs);
-
void blk_dev_change_media_cb(BlockBackend *blk, bool load);
bool blk_dev_has_removable_media(BlockBackend *blk);
bool blk_dev_has_tray(BlockBackend *blk);