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
74
75
|
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2012 ARM Ltd.
*/
#include <linux/linkage.h>
#include <asm/asm-uaccess.h>
#include <asm/assembler.h>
#include <asm/cache.h>
/*
* Copy to user space from a kernel buffer (alignment handled by the hardware)
*
* Parameters:
* x0 - to
* x1 - from
* x2 - n
* Returns:
* x0 - bytes not copied
*/
.macro ldrb1 reg, ptr, val
ldrb \reg, [\ptr], \val
.endm
.macro strb1 reg, ptr, val
uao_user_alternative 9998f, strb, sttrb, \reg, \ptr, \val
.endm
.macro ldrh1 reg, ptr, val
ldrh \reg, [\ptr], \val
.endm
.macro strh1 reg, ptr, val
uao_user_alternative 9997f, strh, sttrh, \reg, \ptr, \val
.endm
.macro ldr1 reg, ptr, val
ldr \reg, [\ptr], \val
.endm
.macro str1 reg, ptr, val
uao_user_alternative 9997f, str, sttr, \reg, \ptr, \val
.endm
.macro ldp1 reg1, reg2, ptr, val
ldp \reg1, \reg2, [\ptr], \val
.endm
.macro stp1 reg1, reg2, ptr, val
uao_stp 9997f, \reg1, \reg2, \ptr, \val
.endm
end .req x5
srcin .req x15
SYM_FUNC_START(__arch_copy_to_user)
add end, x0, x2
mov srcin, x1
#include "copy_template.S"
mov x0, #0
ret
SYM_FUNC_END(__arch_copy_to_user)
EXPORT_SYMBOL(__arch_copy_to_user)
.section .fixup,"ax"
.align 2
9997: cmp dst, dstin
b.ne 9998f
// Before being absolutely sure we couldn't copy anything, try harder
ldrb tmp1w, [srcin]
USER(9998f, sttrb tmp1w, [dst])
add dst, dst, #1
9998: sub x0, end, dst // bytes not copied
ret
.previous
|