diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 6b39963..ea262b0 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -44,6 +44,9 @@
 #define BPF_CALL	0x80	/* function call */
 #define BPF_EXIT	0x90	/* function return */
 
+/* atomic op type fields (stored in immediate) */
+#define BPF_FETCH	0x01	/* fetch previous value into src reg */
+
 /* Register numbers */
 enum {
 	BPF_REG_0 = 0,