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 from user space to 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
| uao_user_alternative 9998f, ldrb, ldtrb, \reg, \ptr, \val
| .endm
|
| .macro strb1 reg, ptr, val
| strb \reg, [\ptr], \val
| .endm
|
| .macro ldrh1 reg, ptr, val
| uao_user_alternative 9997f, ldrh, ldtrh, \reg, \ptr, \val
| .endm
|
| .macro strh1 reg, ptr, val
| strh \reg, [\ptr], \val
| .endm
|
| .macro ldr1 reg, ptr, val
| uao_user_alternative 9997f, ldr, ldtr, \reg, \ptr, \val
| .endm
|
| .macro str1 reg, ptr, val
| str \reg, [\ptr], \val
| .endm
|
| .macro ldp1 reg1, reg2, ptr, val
| uao_ldp 9997f, \reg1, \reg2, \ptr, \val
| .endm
|
| .macro stp1 reg1, reg2, ptr, val
| stp \reg1, \reg2, [\ptr], \val
| .endm
|
| end .req x5
| srcin .req x15
| SYM_FUNC_START(__arch_copy_from_user)
| add end, x0, x2
| mov srcin, x1
| #include "copy_template.S"
| mov x0, #0 // Nothing to copy
| ret
| SYM_FUNC_END(__arch_copy_from_user)
| EXPORT_SYMBOL(__arch_copy_from_user)
|
| .section .fixup,"ax"
| .align 2
| 9997: cmp dst, dstin
| b.ne 9998f
| // Before being absolutely sure we couldn't copy anything, try harder
| USER(9998f, ldtrb tmp1w, [srcin])
| strb tmp1w, [dst], #1
| 9998: sub x0, end, dst // bytes not copied
| ret
| .previous
|
|
