xref: /openbmc/linux/arch/arm/lib/putuser.S (revision e23feb16)
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
35ENTRY(__put_user_1)
36	check_uaccess r0, 1, r1, ip, __put_user_bad
371: TUSER(strb)	r2, [r0]
38	mov	r0, #0
39	mov	pc, lr
40ENDPROC(__put_user_1)
41
42ENTRY(__put_user_2)
43	check_uaccess r0, 2, r1, ip, __put_user_bad
44	mov	ip, r2, lsr #8
45#ifdef CONFIG_THUMB2_KERNEL
46#ifndef __ARMEB__
472: TUSER(strb)	r2, [r0]
483: TUSER(strb)	ip, [r0, #1]
49#else
502: TUSER(strb)	ip, [r0]
513: TUSER(strb)	r2, [r0, #1]
52#endif
53#else	/* !CONFIG_THUMB2_KERNEL */
54#ifndef __ARMEB__
552: TUSER(strb)	r2, [r0], #1
563: TUSER(strb)	ip, [r0]
57#else
582: TUSER(strb)	ip, [r0], #1
593: TUSER(strb)	r2, [r0]
60#endif
61#endif	/* CONFIG_THUMB2_KERNEL */
62	mov	r0, #0
63	mov	pc, lr
64ENDPROC(__put_user_2)
65
66ENTRY(__put_user_4)
67	check_uaccess r0, 4, r1, ip, __put_user_bad
684: TUSER(str)	r2, [r0]
69	mov	r0, #0
70	mov	pc, lr
71ENDPROC(__put_user_4)
72
73ENTRY(__put_user_8)
74	check_uaccess r0, 8, r1, ip, __put_user_bad
75#ifdef CONFIG_THUMB2_KERNEL
765: TUSER(str)	r2, [r0]
776: TUSER(str)	r3, [r0, #4]
78#else
795: TUSER(str)	r2, [r0], #4
806: TUSER(str)	r3, [r0]
81#endif
82	mov	r0, #0
83	mov	pc, lr
84ENDPROC(__put_user_8)
85
86__put_user_bad:
87	mov	r0, #-EFAULT
88	mov	pc, lr
89ENDPROC(__put_user_bad)
90
91.pushsection __ex_table, "a"
92	.long	1b, __put_user_bad
93	.long	2b, __put_user_bad
94	.long	3b, __put_user_bad
95	.long	4b, __put_user_bad
96	.long	5b, __put_user_bad
97	.long	6b, __put_user_bad
98.popsection
99