linux_dsm_epyc7002/arch/arm64/lib/copy_to_user.S
Pavel Tatashin e50be648aa arm64: uaccess: Remove uaccess_*_not_uao asm macros
It is safer and simpler to drop the uaccess assembly macros in favour of
inline C functions. Although this bloats the Image size slightly, it
aligns our user copy routines with '{get,put}_user()' and generally
makes the code a lot easier to reason about.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
[will: tweaked commit message and changed temporary variable names]
Signed-off-by: Will Deacon <will@kernel.org>
2019-11-20 18:51:54 +00:00

68 lines
1.2 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 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 ptr, regB, val
ldrb \ptr, [\regB], \val
.endm
.macro strb1 ptr, regB, val
uao_user_alternative 9998f, strb, sttrb, \ptr, \regB, \val
.endm
.macro ldrh1 ptr, regB, val
ldrh \ptr, [\regB], \val
.endm
.macro strh1 ptr, regB, val
uao_user_alternative 9998f, strh, sttrh, \ptr, \regB, \val
.endm
.macro ldr1 ptr, regB, val
ldr \ptr, [\regB], \val
.endm
.macro str1 ptr, regB, val
uao_user_alternative 9998f, str, sttr, \ptr, \regB, \val
.endm
.macro ldp1 ptr, regB, regC, val
ldp \ptr, \regB, [\regC], \val
.endm
.macro stp1 ptr, regB, regC, val
uao_stp 9998f, \ptr, \regB, \regC, \val
.endm
end .req x5
ENTRY(__arch_copy_to_user)
add end, x0, x2
#include "copy_template.S"
mov x0, #0
ret
ENDPROC(__arch_copy_to_user)
EXPORT_SYMBOL(__arch_copy_to_user)
.section .fixup,"ax"
.align 2
9998: sub x0, end, dst // bytes not copied
ret
.previous