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Linux kernel mirror (for testing)
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1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copy from user space to user space
4 *
5 * Copyright (C) 2012 ARM Ltd.
6 */
7
8#include <linux/linkage.h>
9
10#include <asm/asm-uaccess.h>
11#include <asm/assembler.h>
12#include <asm/cache.h>
13
14/*
15 * Copy from user space to user space (alignment handled by the hardware)
16 *
17 * Parameters:
18 * x0 - to
19 * x1 - from
20 * x2 - n
21 * Returns:
22 * x0 - bytes not copied
23 */
24 .macro ldrb1 reg, ptr, val
25 user_ldst 9998f, ldtrb, \reg, \ptr, \val
26 .endm
27
28 .macro strb1 reg, ptr, val
29 user_ldst 9998f, sttrb, \reg, \ptr, \val
30 .endm
31
32 .macro ldrh1 reg, ptr, val
33 user_ldst 9997f, ldtrh, \reg, \ptr, \val
34 .endm
35
36 .macro strh1 reg, ptr, val
37 user_ldst 9997f, sttrh, \reg, \ptr, \val
38 .endm
39
40 .macro ldr1 reg, ptr, val
41 user_ldst 9997f, ldtr, \reg, \ptr, \val
42 .endm
43
44 .macro str1 reg, ptr, val
45 user_ldst 9997f, sttr, \reg, \ptr, \val
46 .endm
47
48 .macro ldp1 reg1, reg2, ptr, val
49 user_ldp 9997f, \reg1, \reg2, \ptr, \val
50 .endm
51
52 .macro stp1 reg1, reg2, ptr, val
53 user_stp 9997f, \reg1, \reg2, \ptr, \val
54 .endm
55
56end .req x5
57srcin .req x15
58SYM_FUNC_START(__arch_copy_in_user)
59 add end, x0, x2
60 mov srcin, x1
61#include "copy_template.S"
62 mov x0, #0
63 ret
64SYM_FUNC_END(__arch_copy_in_user)
65EXPORT_SYMBOL(__arch_copy_in_user)
66
67 .section .fixup,"ax"
68 .align 2
699997: cmp dst, dstin
70 b.ne 9998f
71 // Before being absolutely sure we couldn't copy anything, try harder
72USER(9998f, ldtrb tmp1w, [srcin])
73USER(9998f, sttrb tmp1w, [dst])
74 add dst, dst, #1
759998: sub x0, end, dst // bytes not copied
76 ret
77 .previous