/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (c) 1996, 1998, 1999, 2004 by Ralf Baechle
* Copyright (c) 1999 Silicon Graphics, Inc.
*/
#include <linux/export.h>
#include <asm/asm.h>
#include <asm/asm-offsets.h>
#include <asm/regdef.h>
#define EX(insn,reg,addr,handler) \
9: insn reg, addr; \
.
section __ex_table,
"a"; \
PTR_WD 9b, handler; \
.previous
/*
* Return the size of a string including the ending NUL character up to a
* maximum of a1 or 0 in case of error.
*
* Note: for performance reasons we deliberately accept that a user may
* make strlen_user and strnlen_user access the first few KSEG0
* bytes. There's nothing secret there. On 64-bit accessing beyond
* the maximum is a tad hairier ...
*/
LEAF(__strnlen_user_asm)
move v0, a0
PTR_ADDU a1, a0 # stop pointer
1:
#ifdef CONFIG_CPU_DADDI_WORKAROUNDS
.
set noat
li AT, 1
#endif
beq v0, a1, 1f # limit reached?
#ifdef CONFIG_EVA
.
set push
.
set eva
EX(lbe, t0, (v0), .Lfault)
.
set pop
#else
EX(lb, t0, (v0), .Lfault)
#endif
.
set noreorder
bnez t0, 1b
1:
#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
PTR_ADDIU v0, 1
#else
PTR_ADDU v0, AT
.
set at
#endif
.
set reorder
PTR_SUBU v0, a0
jr ra
END(__strnlen_user_asm)
.Lfault:
move v0, zero
jr ra
EXPORT_SYMBOL(__strnlen_user_asm)
