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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	uao_user_alternative 9998f, ldrb, ldtrb, \reg, \ptr, \val
26	.endm
27
28	.macro strb1 reg, ptr, val
29	uao_user_alternative 9998f, strb, sttrb, \reg, \ptr, \val
30	.endm
31
32	.macro ldrh1 reg, ptr, val
33	uao_user_alternative 9997f, ldrh, ldtrh, \reg, \ptr, \val
34	.endm
35
36	.macro strh1 reg, ptr, val
37	uao_user_alternative 9997f, strh, sttrh, \reg, \ptr, \val
38	.endm
39
40	.macro ldr1 reg, ptr, val
41	uao_user_alternative 9997f, ldr, ldtr, \reg, \ptr, \val
42	.endm
43
44	.macro str1 reg, ptr, val
45	uao_user_alternative 9997f, str, sttr, \reg, \ptr, \val
46	.endm
47
48	.macro ldp1 reg1, reg2, ptr, val
49	uao_ldp 9997f, \reg1, \reg2, \ptr, \val
50	.endm
51
52	.macro stp1 reg1, reg2, ptr, val
53	uao_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
78