diff --git a/sys/sys/_atomic_subword.h b/sys/sys/_atomic_subword.h
--- a/sys/sys/_atomic_subword.h
+++ b/sys/sys/_atomic_subword.h
@@ -205,4 +205,31 @@
 #undef _ATOMIC_BYTE_SHIFT
 #undef _ATOMIC_HWORD_SHIFT
 
+static __inline void
+atomic_set_short(volatile u_short *p, u_short bit)
+{
+	u_short v;
+
+	v = atomic_load_short(p);
+	for (;;) {
+		if (atomic_fcmpset_short(p, &v, v | bit))
+			break;
+	}
+}
+
+static __inline void
+atomic_clear_short(volatile u_short *p, u_short bit)
+{
+	u_short v;
+
+	v = atomic_load_short(p);
+	for (;;) {
+		if (atomic_fcmpset_short(p, &v, v & ~bit))
+			break;
+	}
+}
+
+#define	atomic_set_16	atomic_set_short
+#define	atomic_clear_16	atomic_clear_short
+
 #endif	/* _SYS__ATOMIC_SUBWORD_H_ */