Implement kcopy(), like bcopy(), but aborts if a fault is encountered.

Required for UVM.

sys/arch/m68k/m68k/copy.s

@@ -1,6 +1,7 @@
-/*	$NetBSD: copy.s,v 1.28 1997/05/21 03:51:04 jeremy Exp $	*/
+/*	$NetBSD: copy.s,v 1.29 1998/02/15 21:18:45 thorpej Exp $	*/
 
 /*-
+ * Copyright (c) 1998 Jason R. Thorpe.  All rights reserved.
  * Copyright (c) 1994, 1995 Charles Hannum.
  * Copyright (c) 1990 The Regents of the University of California.
  * All rights reserved.
@@ -43,6 +44,8 @@
  * copyin/copyout, fuword/suword, etc.
  */
 
+#include "opt_uvm.h"
+
 #include <sys/errno.h>
 #include <machine/asm.h>
 
@@ -311,6 +314,33 @@ Lcosfault:
 	moveq	#EFAULT,d0
 	bra	Lcosdone
 
+#if defined(UVM)
+/*
+ * kcopy(const void *src, void *dst, size_t len);
+ *
+ * Copy len bytes from src to dst, aborting if we encounter a page fault.
+ */
+ENTRY(kcopy)
+	link	a6,#0
+	movl	_C_LABEL(curpcb),a0	| set fault handler
+	movl	#Lkcfault,a0@(PCB_ONFAULT)
+	movl	a6@(16),sp@-		| push len
+	movl	a6@(12),sp@-		| push dst
+	movl	a6@(8),sp@-		| push src
+	jbsr	_C_LABEL(bcopy)		| copy it
+	addl	#12,sp			| pop args
+	clrl	d0			| success!
+Lkcdone:
+	movl	_C_LABEL(curpcb),a0	| clear fault handler
+	clrl	a0@(PCB_ONFAULT)
+	unlk	a6
+	rts
+Lkcfault:
+	addl	#16,sp			| pop args and return address
+	moveq	#EFAULT,d0		| indicate a fault
+	bra	Lkcdone
+#endif /* UVM */
+
 /*
  * fuword(caddr_t uaddr);
  * Fetch an int from the user's address space.