tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * linux/arch/unicore32/lib/strnlen_user.S
4 *
5 * Code specific to PKUnity SoC and UniCore ISA
6 *
7 * Copyright (C) 2001-2010 GUAN Xue-tao
8 */
9#include <linux/linkage.h>
10#include <asm/assembler.h>
11#include <asm/errno.h>
12
13 .text
14 .align 5
15
16/* Prototype: unsigned long __strnlen_user(const char *str, long n)
17 * Purpose : get length of a string in user memory
18 * Params : str - address of string in user memory
19 * Returns : length of string *including terminator*
20 * or zero on exception, or n + 1 if too long
21 */
22ENTRY(__strnlen_user)
23 mov r2, r0
241:
25 ldrusr r3, r0, 1
26 cxor.a r3, #0
27 beq 2f
28 sub.a r1, r1, #1
29 bne 1b
30 add r0, r0, #1
312: sub r0, r0, r2
32 mov pc, lr
33ENDPROC(__strnlen_user)
34
35 .pushsection .fixup,"ax"
36 .align 0
379001: mov r0, #0
38 mov pc, lr
39 .popsection