74 lines
1.4 KiB
ArmAsm
74 lines
1.4 KiB
ArmAsm
/* 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
|
|
user_ldst 9998f, ldtrb, \reg, \ptr, \val
|
|
.endm
|
|
|
|
.macro strb1 reg, ptr, val
|
|
strb \reg, [\ptr], \val
|
|
.endm
|
|
|
|
.macro ldrh1 reg, ptr, val
|
|
user_ldst 9997f, ldtrh, \reg, \ptr, \val
|
|
.endm
|
|
|
|
.macro strh1 reg, ptr, val
|
|
strh \reg, [\ptr], \val
|
|
.endm
|
|
|
|
.macro ldr1 reg, ptr, val
|
|
user_ldst 9997f, ldtr, \reg, \ptr, \val
|
|
.endm
|
|
|
|
.macro str1 reg, ptr, val
|
|
str \reg, [\ptr], \val
|
|
.endm
|
|
|
|
.macro ldp1 reg1, reg2, ptr, val
|
|
user_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
|
|
|
|
// Exception fixups
|
|
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
|
|
SYM_FUNC_END(__arch_copy_from_user)
|
|
EXPORT_SYMBOL(__arch_copy_from_user)
|