int bdrv_set_read_only(BlockDriverState *bs, bool read_only, Error **errp) { /* Do not set read_only if copy_on_read is enabled */ if (bs->copy_on_read && read_only) { error_setg(errp, "Can't set node '%s' to r/o with copy-on-read enabled", bdrv_get_device_or_node_name(bs)); return -EINVAL; } /* Do not clear read_only if it is prohibited */ if (!read_only && !(bs->open_flags & BDRV_O_ALLOW_RDWR)) { error_setg(errp, "Node '%s' is read only", bdrv_get_device_or_node_name(bs)); return -EPERM; } bs->read_only = read_only; return 0; }