1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
|
/*
* linux/arch/arm/lib/getuser.S
*
* Copyright (C) 2001 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Idea from x86 version, (C) Copyright 1998 Linus Torvalds
*
* These functions have a non-standard call interface to make them more
* efficient, especially as they return an error value in addition to
* the "real" return value.
*
* __get_user_X
*
* Inputs: r0 contains the address
* Outputs: r0 is the error code
* r2, r3 contains the zero-extended value
* lr corrupted
*
* No other registers must be altered. (see <asm/uaccess.h>
* for specific ASM register usage).
*
* Note that ADDR_LIMIT is either 0 or 0xc0000000.
* Note also that it is intended that __get_user_bad is not global.
*/
#include <linux/linkage.h>
#include <asm/errno.h>
#include <asm/domain.h>
ENTRY(__get_user_1)
1: T(ldrb) r2, [r0]
mov r0, #0
mov pc, lr
ENDPROC(__get_user_1)
ENTRY(__get_user_2)
#ifdef CONFIG_THUMB2_KERNEL
2: T(ldrb) r2, [r0]
3: T(ldrb) r3, [r0, #1]
#else
2: T(ldrb) r2, [r0], #1
3: T(ldrb) r3, [r0]
#endif
#ifndef __ARMEB__
orr r2, r2, r3, lsl #8
#else
orr r2, r3, r2, lsl #8
#endif
mov r0, #0
mov pc, lr
ENDPROC(__get_user_2)
ENTRY(__get_user_4)
4: T(ldr) r2, [r0]
mov r0, #0
mov pc, lr
ENDPROC(__get_user_4)
__get_user_bad:
mov r2, #0
mov r0, #-EFAULT
mov pc, lr
ENDPROC(__get_user_bad)
.pushsection __ex_table, "a"
.long 1b, __get_user_bad
.long 2b, __get_user_bad
.long 3b, __get_user_bad
.long 4b, __get_user_bad
.popsection
|
