+++ b/block/raw-format.c
@@ -444,6 +444,7 @@ static int raw_open(BlockDriverState *bs, QDict *options,
int flags,
BDRVRawState *s = bs->opaque;
bool has_size;
uint64_t offset, size;
+ BdrvChildRole file_role;
int ret;
ret = raw_read_options(options, &offset, &has_size, &size, errp);
@@ -451,8 +452,18 @@ static int raw_open(BlockDriverState *bs, QDict *options,
int flags,
return ret;
}
- bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file, 0,
- false, errp);
+ /*
+ * Without offset and a size limit, this driver behaves very much
+ * like a filter. With any such limit, it does not.
+ */
+ if (offset || has_size) {
+ file_role = BDRV_CHILD_DATA | BDRV_CHILD_PRIMARY;
+ } else {
+ file_role = BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY;
+ }