linux/arch/mips/lib/strlen_user.S
Markos Chandras 053970542f MIPS: lib: strlen_user: Add EVA support
In non-EVA mode, strlen_user* aliases are used for the
strlen_kernel* symbols since the code is identical. In EVA
mode, new strlen_user* symbols are used which use the EVA
specific instructions to load values from userspace.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2014-03-26 23:09:13 +01:00

65 lines
1.3 KiB
ArmAsm

/*
* 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.
* Copyright (C) 2011 MIPS Technologies, 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 0)
*
* Return 0 for error
*/
.macro __BUILD_STRLEN_ASM func
LEAF(__strlen_\func\()_asm)
LONG_L v0, TI_ADDR_LIMIT($28) # pointer ok?
and v0, a0
bnez v0, .Lfault\@
FEXPORT(__strlen_\func\()_nocheck_asm)
move v0, a0
.ifeqs "\func", "kernel"
1: EX(lbu, v1, (v0), .Lfault\@)
.else
1: EX(lbue, v1, (v0), .Lfault\@)
.endif
PTR_ADDIU v0, 1
bnez v1, 1b
PTR_SUBU v0, a0
jr ra
END(__strlen_\func\()_asm)
.Lfault\@: move v0, zero
jr ra
.endm
#ifndef CONFIG_EVA
/* Set aliases */
.global __strlen_user_asm
.global __strlen_user_nocheck_asm
.set __strlen_user_asm, __strlen_kernel_asm
.set __strlen_user_nocheck_asm, __strlen_kernel_nocheck_asm
#endif
__BUILD_STRLEN_ASM kernel
#ifdef CONFIG_EVA
.set push
.set eva
__BUILD_STRLEN_ASM user
.set pop
#endif