diff --git a/block/ioctl.c b/block/ioctl.c
index ff241e6..8ba1ed8 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -89,6 +89,8 @@
 		return -EINVAL;
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
+	if (bdev->bd_part_count)
+		return -EBUSY;
 
 	/*
 	 * Reopen the device to revalidate the driver state and force a