| /* |
| * 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) |
