| /* |
| * 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, 1999 by Ralf Baechle |
| * Copyright (C) 2011 MIPS Technologies, Inc. |
| */ |
| #include <linux/errno.h> |
| #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 |
| |
| /* |
| * Returns: -EFAULT if exception before terminator, N if the entire |
| * buffer filled, else strlen. |
| */ |
| |
| /* |
| * Ugly special case have to check: we might get passed a user space |
| * pointer which wraps into the kernel space. We don't deal with that. If |
| * it happens at most some bytes of the exceptions handlers will be copied. |
| */ |
| |
| LEAF(__strncpy_from_user_asm) |
| move t0, zero |
| move v1, a1 |
| #ifdef CONFIG_EVA |
| .set push |
| .set eva |
| 1: EX(lbue, v0, (v1), .Lfault) |
| .set pop |
| #else |
| 1: EX(lbu, v0, (v1), .Lfault) |
| #endif |
| PTR_ADDIU v1, 1 |
| R10KCBARRIER(0(ra)) |
| sb v0, (a0) |
| beqz v0, 2f |
| PTR_ADDIU t0, 1 |
| PTR_ADDIU a0, 1 |
| bne t0, a2, 1b |
| 2: PTR_ADDU v0, a1, t0 |
| xor v0, a1 |
| bltz v0, .Lfault |
| move v0, t0 |
| jr ra # return n |
| END(__strncpy_from_user_asm) |
| |
| .Lfault: |
| li v0, -EFAULT |
| jr ra |
| |
| .section __ex_table,"a" |
| PTR_WD 1b, .Lfault |
| .previous |
| |
| EXPORT_SYMBOL(__strncpy_from_user_asm) |
