memcpy.S patch in 64-bit

[Carsten Langgaard <carstenl@mips.com>]

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The __copy_user function (in arch/mips64/lib/memcpy.S) calls __bzero.
We can't do that because __bzero might modify len, which we want to
return in case of an error.
The following patch take care of the problem.

/Carsten


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Index: arch/mips64/lib/memcpy.S
===================================================================
RCS file: /cvs/linux/arch/mips64/lib/memcpy.S,v
retrieving revision 1.9.2.1
diff -u -r1.9.2.1 memcpy.S
--- arch/mips64/lib/memcpy.S	2002/08/05 23:53:36	1.9.2.1
+++ arch/mips64/lib/memcpy.S	2002/08/08 13:19:10
@@ -762,8 +762,18 @@
 	dsubu	a2, AT, ta0			# a2 bytes to go
 	daddu	a0, ta0				# compute start address in a1
 	dsubu	a0, a1
-	j	__bzero
-	 move	a1, zero
+	/*
+	 * Clear len bytes starting at dst.  Can't call __bzero because it
+	 * might modify len.  An inefficient loop for these rare times...
+	 */
+	beqz	a2, 2f
+	 dsubu	a1, a2, 1
+1:	sb	zero, 0(a0)
+	daddu	a0, a0, 1
+	bnez	a1, 1b
+	 dsubu	a1, a1, 1
+2:	jr	ra
+	 nop
 
 s_fixup:
 	jr	ra