[deliverable/linux.git] / arch / sparc / lib / copy_in_user.S

/* copy_in_user.S: Copy from userspace to userspace.
 *
 * Copyright (C) 1999, 2000, 2004 David S. Miller (davem@redhat.com)
 */

#include <linux/linkage.h>
#include <asm/asi.h>
#include <asm/export.h>

#define XCC xcc

#define EX(x,y)			\
98:	x,y;			\
	.section __ex_table,"a";\
	.align 4;		\
	.word 98b, __retl_one;	\
	.text;			\
	.align 4;

	.register	%g2,#scratch
	.register	%g3,#scratch

	.text
	.align	32

	/* Don't try to get too fancy here, just nice and
	 * simple.  This is predominantly used for well aligned
	 * small copies in the compat layer.  It is also used
	 * to copy register windows around during thread cloning.
	 */

ENTRY(___copy_in_user)	/* %o0=dst, %o1=src, %o2=len */
	cmp		%o2, 0
	be,pn		%XCC, 85f
	 or		%o0, %o1, %o3
	cmp		%o2, 16
	bleu,a,pn	%XCC, 80f
	 or		%o3, %o2, %o3

	/* 16 < len <= 64 */
	andcc		%o3, 0x7, %g0
	bne,pn		%XCC, 90f
	 nop

	andn		%o2, 0x7, %o4
	and		%o2, 0x7, %o2
1:	subcc		%o4, 0x8, %o4
	EX(ldxa [%o1] %asi, %o5)
	EX(stxa %o5, [%o0] %asi)
	add		%o1, 0x8, %o1
	bgu,pt		%XCC, 1b
	 add		%o0, 0x8, %o0
	andcc		%o2, 0x4, %g0
	be,pt		%XCC, 1f
	 nop
	sub		%o2, 0x4, %o2
	EX(lduwa [%o1] %asi, %o5)
	EX(stwa %o5, [%o0] %asi)
	add		%o1, 0x4, %o1
	add		%o0, 0x4, %o0
1:	cmp		%o2, 0
	be,pt		%XCC, 85f
	 nop
	ba,pt		%xcc, 90f
	 nop

80:	/* 0 < len <= 16 */
	andcc		%o3, 0x3, %g0
	bne,pn		%XCC, 90f
	 nop

82:
	subcc		%o2, 4, %o2
	EX(lduwa [%o1] %asi, %g1)
	EX(stwa %g1, [%o0] %asi)
	add		%o1, 4, %o1
	bgu,pt		%XCC, 82b
	 add		%o0, 4, %o0

85:	retl
	 clr		%o0

	.align	32
90:
	subcc		%o2, 1, %o2
	EX(lduba [%o1] %asi, %g1)
	EX(stba %g1, [%o0] %asi)
	add		%o1, 1, %o1
	bgu,pt		%XCC, 90b
	 add		%o0, 1, %o0
	retl
	 clr		%o0
ENDPROC(___copy_in_user)
EXPORT_SYMBOL(___copy_in_user)
Commit	Line	Data
1da177e4 LT	1	/* copy_in_user.S: Copy from userspace to userspace.
	2	*
	3	* Copyright (C) 1999, 2000, 2004 David S. Miller (davem@redhat.com)
	4	*/
	5
aeb39876	6	#include <linux/linkage.h>
1da177e4	7	#include <asm/asi.h>
d3867f04	8	#include <asm/export.h>
1da177e4 LT	9
	10	#define XCC xcc
	11
	12	#define EX(x,y) \
	13	98: x,y; \
4d000d5b	14	.section __ex_table,"a";\
1da177e4	15	.align 4; \
40bdac7d	16	.word 98b, __retl_one; \
1da177e4 LT	17	.text; \
	18	.align 4;
	19
	20	.register %g2,#scratch
	21	.register %g3,#scratch
	22
	23	.text
	24	.align 32
	25
	26	/* Don't try to get too fancy here, just nice and
	27	* simple. This is predominantly used for well aligned
	28	* small copies in the compat layer. It is also used
	29	* to copy register windows around during thread cloning.
	30	*/
	31
aeb39876	32	ENTRY(___copy_in_user) /* %o0=dst, %o1=src, %o2=len */
1da177e4 LT	33	cmp %o2, 0
	34	be,pn %XCC, 85f
	35	or %o0, %o1, %o3
	36	cmp %o2, 16
	37	bleu,a,pn %XCC, 80f
	38	or %o3, %o2, %o3
	39
	40	/* 16 < len <= 64 */
	41	andcc %o3, 0x7, %g0
	42	bne,pn %XCC, 90f
aeb39876	43	nop
1da177e4 LT	44
	45	andn %o2, 0x7, %o4
	46	and %o2, 0x7, %o2
	47	1: subcc %o4, 0x8, %o4
	48	EX(ldxa [%o1] %asi, %o5)
aeb39876 DM	49	EX(stxa %o5, [%o0] %asi)
aeb39876 DM	50	add %o1, 0x8, %o1
1da177e4	51	bgu,pt %XCC, 1b
aeb39876	52	add %o0, 0x8, %o0
1da177e4 LT	53	andcc %o2, 0x4, %g0
	54	be,pt %XCC, 1f
	55	nop
	56	sub %o2, 0x4, %o2
	57	EX(lduwa [%o1] %asi, %o5)
aeb39876	58	EX(stwa %o5, [%o0] %asi)
1da177e4	59	add %o1, 0x4, %o1
aeb39876	60	add %o0, 0x4, %o0
1da177e4 LT	61	1: cmp %o2, 0
	62	be,pt %XCC, 85f
	63	nop
	64	ba,pt %xcc, 90f
	65	nop
	66
	67	80: /* 0 < len <= 16 */
	68	andcc %o3, 0x3, %g0
	69	bne,pn %XCC, 90f
aeb39876	70	nop
1da177e4 LT	71
	72	82:
	73	subcc %o2, 4, %o2
	74	EX(lduwa [%o1] %asi, %g1)
aeb39876 DM	75	EX(stwa %g1, [%o0] %asi)
aeb39876 DM	76	add %o1, 4, %o1
1da177e4	77	bgu,pt %XCC, 82b
aeb39876	78	add %o0, 4, %o0
1da177e4 LT	79
	80	85: retl
	81	clr %o0
	82
	83	.align 32
	84	90:
	85	subcc %o2, 1, %o2
	86	EX(lduba [%o1] %asi, %g1)
aeb39876 DM	87	EX(stba %g1, [%o0] %asi)
aeb39876 DM	88	add %o1, 1, %o1
1da177e4	89	bgu,pt %XCC, 90b
aeb39876	90	add %o0, 1, %o0
1da177e4 LT	91	retl
1da177e4 LT	92	clr %o0
aeb39876	93	ENDPROC(___copy_in_user)
d3867f04	94	EXPORT_SYMBOL(___copy_in_user)