2005-04-17 06:20:36 +08:00
|
|
|
/*
|
|
|
|
* 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 <asm/asm.h>
|
2005-09-10 04:32:31 +08:00
|
|
|
#include <asm/asm-offsets.h>
|
2005-04-17 06:20:36 +08:00
|
|
|
#include <asm/regdef.h>
|
|
|
|
|
|
|
|
#define EX(insn,reg,addr,handler) \
|
|
|
|
9: insn reg, addr; \
|
|
|
|
.section __ex_table,"a"; \
|
|
|
|
PTR 9b, handler; \
|
|
|
|
.previous
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Return the size of a string including the ending NUL character upto 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)
|
|
|
|
LONG_L v0, TI_ADDR_LIMIT($28) # pointer ok?
|
|
|
|
and v0, a0
|
|
|
|
bnez v0, fault
|
|
|
|
|
|
|
|
FEXPORT(__strnlen_user_nocheck_asm)
|
|
|
|
move v0, a0
|
|
|
|
PTR_ADDU a1, a0 # stop pointer
|
|
|
|
1: beq v0, a1, 1f # limit reached?
|
|
|
|
EX(lb, t0, (v0), fault)
|
|
|
|
PTR_ADDU v0, 1
|
|
|
|
bnez t0, 1b
|
|
|
|
1: PTR_SUBU v0, a0
|
|
|
|
jr ra
|
|
|
|
END(__strnlen_user_asm)
|
|
|
|
|
|
|
|
fault: move v0, zero
|
|
|
|
jr ra
|