+ if (!drv->create_opts) {
+ error_setg(errp, "Driver '%s' does not support image creation",
+ drv->format_name);
+ return -ENOTSUP;
+ }
+
+ /*
+ * 'opts' contains a QemuOptsList with a combination of format and protocol
+ * default values.
+ *
+ * The format properly removes its options, but the default values remain
+ * in 'opts->list'. So if the protocol has options with the same name
+ * (e.g. rbd has 'cluster_size' as qcow2), it will see the default values
+ * of the format, since for overlapping options, the format wins.
+ *
+ * To avoid this issue, lets convert QemuOpts to QDict, in this way we take
+ * only the set options, and then convert it back to QemuOpts, using the
+ * create_opts of the protocol. So the new QemuOpts, will contain only the
+ * protocol defaults.
+ */
+ qdict = qemu_opts_to_qdict(opts, NULL);
+ protocol_opts = qemu_opts_from_qdict(drv->create_opts, qdict, errp);
+ if (protocol_opts == NULL) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = bdrv_create(drv, filename, protocol_opts, errp);
+out:
+ qemu_opts_del(protocol_opts);
+ qobject_unref(qdict);
+ return ret;