/* * 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 #include #include #include #include #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)