diff --git a/sys/arch/alpha/alpha/vm_machdep.c b/sys/arch/alpha/alpha/vm_machdep.c
index ee2cdbae5ee7..ce672b966059 100644
--- a/sys/arch/alpha/alpha/vm_machdep.c
+++ b/sys/arch/alpha/alpha/vm_machdep.c
@@ -1,4 +1,4 @@
-/* $NetBSD: vm_machdep.c,v 1.46 1999/05/13 21:58:32 thorpej Exp $ */
+/* $NetBSD: vm_machdep.c,v 1.47 1999/05/16 22:24:16 thorpej Exp $ */
 
 /*
  * Copyright (c) 1994, 1995, 1996 Carnegie-Mellon University.
@@ -29,7 +29,7 @@
 
 #include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
 
-__KERNEL_RCSID(0, "$NetBSD: vm_machdep.c,v 1.46 1999/05/13 21:58:32 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vm_machdep.c,v 1.47 1999/05/16 22:24:16 thorpej Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -370,22 +370,7 @@ pagemove(from, to, size)
 extern vm_map_t phys_map;
 
 /*
- * Map an IO request into kernel virtual address space.  Requests fall into
- * one of five catagories:
- *
- *	B_PHYS|B_UAREA:	User u-area swap.
- *			Address is relative to start of u-area (p_addr).
- *	B_PHYS|B_PAGET:	User page table swap.
- *			Address is a kernel VA in usrpt (Usrptmap).
- *	B_PHYS|B_DIRTY:	Dirty page push.
- *			Address is a VA in proc2's address space.
- *	B_PHYS|B_PGIN:	Kernel pagein of user pages.
- *			Address is VA in user's address space.
- *	B_PHYS:		User "raw" IO request.
- *			Address is VA in user's address space.
- *
- * All requests are (re)mapped into kernel VA space via the useriomap
- * (a name with only slightly more meaning than "kernelmap")
+ * Map a user I/O request into kernel virtual address space.
  */
 void
 vmapbuf(bp, len)
@@ -417,8 +402,7 @@ vmapbuf(bp, len)
 }
 
 /*
- * Free the io map PTEs associated with this IO operation.
- * We also invalidate the TLB entries and restore the original b_addr.
+ * Unmap a previously-mapped user I/O request.
  */
 void
 vunmapbuf(bp, len)