xref: /openbmc/linux/arch/arm/lib/putuser.S (revision 82003e04)
1/*
2 *  linux/arch/arm/lib/putuser.S
3 *
4 *  Copyright (C) 2001 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 *  Idea from x86 version, (C) Copyright 1998 Linus Torvalds
11 *
12 * These functions have a non-standard call interface to make
13 * them more efficient, especially as they return an error
14 * value in addition to the "real" return value.
15 *
16 * __put_user_X
17 *
18 * Inputs:	r0 contains the address
19 *		r1 contains the address limit, which must be preserved
20 *		r2, r3 contains the value
21 * Outputs:	r0 is the error code
22 *		lr corrupted
23 *
24 * No other registers must be altered.  (see <asm/uaccess.h>
25 * for specific ASM register usage).
26 *
27 * Note that ADDR_LIMIT is either 0 or 0xc0000000
28 * Note also that it is intended that __put_user_bad is not global.
29 */
30#include <linux/linkage.h>
31#include <asm/assembler.h>
32#include <asm/errno.h>
33#include <asm/domain.h>
34#include <asm/export.h>
35
36ENTRY(__put_user_1)
37	check_uaccess r0, 1, r1, ip, __put_user_bad
381: TUSER(strb)	r2, [r0]
39	mov	r0, #0
40	ret	lr
41ENDPROC(__put_user_1)
42EXPORT_SYMBOL(__put_user_1)
43
44ENTRY(__put_user_2)
45	check_uaccess r0, 2, r1, ip, __put_user_bad
46	mov	ip, r2, lsr #8
47#ifdef CONFIG_THUMB2_KERNEL
48#ifndef __ARMEB__
492: TUSER(strb)	r2, [r0]
503: TUSER(strb)	ip, [r0, #1]
51#else
522: TUSER(strb)	ip, [r0]
533: TUSER(strb)	r2, [r0, #1]
54#endif
55#else	/* !CONFIG_THUMB2_KERNEL */
56#ifndef __ARMEB__
572: TUSER(strb)	r2, [r0], #1
583: TUSER(strb)	ip, [r0]
59#else
602: TUSER(strb)	ip, [r0], #1
613: TUSER(strb)	r2, [r0]
62#endif
63#endif	/* CONFIG_THUMB2_KERNEL */
64	mov	r0, #0
65	ret	lr
66ENDPROC(__put_user_2)
67EXPORT_SYMBOL(__put_user_2)
68
69ENTRY(__put_user_4)
70	check_uaccess r0, 4, r1, ip, __put_user_bad
714: TUSER(str)	r2, [r0]
72	mov	r0, #0
73	ret	lr
74ENDPROC(__put_user_4)
75EXPORT_SYMBOL(__put_user_4)
76
77ENTRY(__put_user_8)
78	check_uaccess r0, 8, r1, ip, __put_user_bad
79#ifdef CONFIG_THUMB2_KERNEL
805: TUSER(str)	r2, [r0]
816: TUSER(str)	r3, [r0, #4]
82#else
835: TUSER(str)	r2, [r0], #4
846: TUSER(str)	r3, [r0]
85#endif
86	mov	r0, #0
87	ret	lr
88ENDPROC(__put_user_8)
89EXPORT_SYMBOL(__put_user_8)
90
91__put_user_bad:
92	mov	r0, #-EFAULT
93	ret	lr
94ENDPROC(__put_user_bad)
95
96.pushsection __ex_table, "a"
97	.long	1b, __put_user_bad
98	.long	2b, __put_user_bad
99	.long	3b, __put_user_bad
100	.long	4b, __put_user_bad
101	.long	5b, __put_user_bad
102	.long	6b, __put_user_bad
103.popsection
104