diff --git a/sys/sys/mbuf.h b/sys/sys/mbuf.h
index c88e647b7f9..6ce9922a03c 100644
--- a/sys/sys/mbuf.h
+++ b/sys/sys/mbuf.h
@@ -437,6 +437,8 @@ extern	int nmbclusters;		/* Maximum number of clusters */
 extern	int nmbcnt;			/* Scale kmem_map for counter space */
 extern	int nmbufs;			/* Maximum number of mbufs */
 
+struct	uio;
+
 void		 _mext_free(struct mbuf *);
 void		 m_adj(struct mbuf *, int);
 int		 m_apply(struct mbuf *, int, int,
@@ -474,6 +476,8 @@ void		 m_print(const struct mbuf *);
 struct	mbuf	*m_pulldown(struct mbuf *, int, int, int *);
 struct	mbuf	*m_pullup(struct mbuf *, int);
 struct	mbuf	*m_split(struct mbuf *, int, int);
+struct	mbuf *
+	m_uiotombuf(struct uio *uio, int how, int len);
 
 /*
  * Packets may have annotations attached by affixing a list
diff --git a/sys/sys/uio.h b/sys/sys/uio.h
index d95552930b0..288903d98ae 100644
--- a/sys/sys/uio.h
+++ b/sys/sys/uio.h
@@ -95,8 +95,6 @@ int	uiomove(void *cp, int n, struct uio *uio);
 int	uiomove_frombuf(void *buf, int buflen, struct uio *uio);
 int	uiomoveco(void *cp, int n, struct uio *uio, struct vm_object *obj,
 	    int disposable);
-struct mbuf *
-	m_uiotombuf(struct uio *uio, int how, int len);
 
 #else /* !_KERNEL */