mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-29 07:04:10 +08:00
caab277b1d
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 503 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Enrico Weigelt <info@metux.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
53 lines
1.1 KiB
ArmAsm
53 lines
1.1 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
* Based on arch/arm/lib/clear_user.S
|
|
*
|
|
* Copyright (C) 2012 ARM Ltd.
|
|
*/
|
|
#include <linux/linkage.h>
|
|
|
|
#include <asm/asm-uaccess.h>
|
|
#include <asm/assembler.h>
|
|
|
|
.text
|
|
|
|
/* Prototype: int __arch_clear_user(void *addr, size_t sz)
|
|
* Purpose : clear some user memory
|
|
* Params : addr - user memory address to clear
|
|
* : sz - number of bytes to clear
|
|
* Returns : number of bytes NOT cleared
|
|
*
|
|
* Alignment fixed up by hardware.
|
|
*/
|
|
ENTRY(__arch_clear_user)
|
|
uaccess_enable_not_uao x2, x3, x4
|
|
mov x2, x1 // save the size for fixup return
|
|
subs x1, x1, #8
|
|
b.mi 2f
|
|
1:
|
|
uao_user_alternative 9f, str, sttr, xzr, x0, 8
|
|
subs x1, x1, #8
|
|
b.pl 1b
|
|
2: adds x1, x1, #4
|
|
b.mi 3f
|
|
uao_user_alternative 9f, str, sttr, wzr, x0, 4
|
|
sub x1, x1, #4
|
|
3: adds x1, x1, #2
|
|
b.mi 4f
|
|
uao_user_alternative 9f, strh, sttrh, wzr, x0, 2
|
|
sub x1, x1, #2
|
|
4: adds x1, x1, #1
|
|
b.mi 5f
|
|
uao_user_alternative 9f, strb, sttrb, wzr, x0, 0
|
|
5: mov x0, #0
|
|
uaccess_disable_not_uao x2, x3
|
|
ret
|
|
ENDPROC(__arch_clear_user)
|
|
EXPORT_SYMBOL(__arch_clear_user)
|
|
|
|
.section .fixup,"ax"
|
|
.align 2
|
|
9: mov x0, x2 // return the original size
|
|
ret
|
|
.previous
|