| /* |
| * 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> |
| #include <asm/asm-offsets.h> |
| #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, .Lfault |
| |
| 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), .Lfault) |
| PTR_ADDU v0, 1 |
| bnez t0, 1b |
| 1: PTR_SUBU v0, a0 |
| jr ra |
| END(__strnlen_user_asm) |
| |
| .Lfault: |
| move v0, zero |
| jr ra |