android_kernel_xiaomi_sm8350/arch/arm/lib/strncpy_from_user.S
Russell King 02fcb97436 [ARM] Remove the __arch_* layer from uaccess.h
Back in the days when we had armo (26-bit) and armv (32-bit) combined,
we had an additional layer to the uaccess macros to ensure correct
typing.  Since we no longer have 26-bit in this tree, we no longer
need this layer, so eliminate it.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-06-28 17:53:27 +01:00

43 lines
952 B
ArmAsm

/*
* linux/arch/arm/lib/strncpy_from_user.S
*
* Copyright (C) 1995-2000 Russell King
*
* 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.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/errno.h>
.text
.align 5
/*
* Copy a string from user space to kernel space.
* r0 = dst, r1 = src, r2 = byte length
* returns the number of characters copied (strlen of copied string),
* -EFAULT on exception, or "len" if we fill the whole buffer
*/
ENTRY(__strncpy_from_user)
mov ip, r1
1: subs r2, r2, #1
USER( ldrplbt r3, [r1], #1)
bmi 2f
strb r3, [r0], #1
teq r3, #0
bne 1b
sub r1, r1, #1 @ take NUL character out of count
2: sub r0, r1, ip
mov pc, lr
.section .fixup,"ax"
.align 0
9001: mov r3, #0
strb r3, [r0, #0] @ null terminate
mov r0, #-EFAULT
mov pc, lr
.previous