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/*
* Based on arch/arm/lib/putuser.S
*
* Copyright (C) 2012 ARM Ltd.
* Idea from x86 version, (C) Copyright 1998 Linus Torvalds
*
* 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/>.
*
* These functions have a non-standard call interface to make
* them more efficient, especially as they return an error
* value in addition to the "real" return value.
*
* __put_user_X
*
* Inputs: x0 contains the address
* x2, x3 contains the value
* Outputs: x0 is the error code
* lr corrupted
*
* No other registers must be altered. (see <asm/uaccess.h>
* for specific ASM register usage).
*
* Note that it is intended that __put_user_bad is not global.
*/
#include <linux/linkage.h>
#include <asm/errno.h>
ENTRY(__put_user_1)
1: strb w2, [x0]
mov x0, #0
ret
ENDPROC(__put_user_1)
ENTRY(__put_user_2)
2: strh w2, [x0]
mov x0, #0
ret
ENDPROC(__put_user_2)
ENTRY(__put_user_4)
3: str w2, [x0]
mov x0, #0
ret
ENDPROC(__put_user_4)
ENTRY(__put_user_8)
4: str x2, [x0]
mov x0, #0
ret
ENDPROC(__put_user_8)
__put_user_bad:
mov x0, #-EFAULT
ret
ENDPROC(__put_user_bad)
.section __ex_table, "a"
.quad 1b, __put_user_bad
.quad 2b, __put_user_bad
.quad 3b, __put_user_bad
.quad 4b, __put_user_bad
.previous
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