blob: 80223177260857c97246774530e5779cf07f6c37 [file] [log] [blame]
/* 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
.macro strb1 reg, ptr, val
user_ldst 9998f, sttrb, \reg, \ptr, \val
.macro ldrh1 reg, ptr, val
ldrh \reg, [\ptr], \val
.macro strh1 reg, ptr, val
user_ldst 9997f, sttrh, \reg, \ptr, \val
.macro ldr1 reg, ptr, val
ldr \reg, [\ptr], \val
.macro str1 reg, ptr, val
user_ldst 9997f, sttr, \reg, \ptr, \val
.macro ldp1 reg1, reg2, ptr, val
ldp \reg1, \reg2, [\ptr], \val
.macro stp1 reg1, reg2, ptr, val
user_stp 9997f, \reg1, \reg2, \ptr, \val
end .req x5
srcin .req x15
add end, x0, x2
mov srcin, x1
#include "copy_template.S"
mov x0, #0
// Exception fixups
9997: cmp dst, dstin 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