4968db4b9c
In non-EVA mode, a strlen_user* alias is used for the strlen_kernel* symbols since the code is identical. In EVA mode, a new strlen_user* symbol is used which uses the EVA specific instructions to load values from userspace. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
71 lines
1.6 KiB
ArmAsm
71 lines
1.6 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.
|
|
*/
|
|
#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 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 ...
|
|
*/
|
|
.macro __BUILD_STRNLEN_ASM func
|
|
LEAF(__strnlen_\func\()_asm)
|
|
LONG_L v0, TI_ADDR_LIMIT($28) # pointer ok?
|
|
and v0, a0
|
|
bnez v0, .Lfault\@
|
|
|
|
FEXPORT(__strnlen_\func\()_nocheck_asm)
|
|
move v0, a0
|
|
PTR_ADDU a1, a0 # stop pointer
|
|
1: beq v0, a1, 1f # limit reached?
|
|
.ifeqs "\func", "kernel"
|
|
EX(lb, t0, (v0), .Lfault\@)
|
|
.else
|
|
EX(lbe, t0, (v0), .Lfault\@)
|
|
.endif
|
|
PTR_ADDIU v0, 1
|
|
bnez t0, 1b
|
|
1: PTR_SUBU v0, a0
|
|
jr ra
|
|
END(__strnlen_\func\()_asm)
|
|
|
|
.Lfault\@:
|
|
move v0, zero
|
|
jr ra
|
|
.endm
|
|
|
|
#ifndef CONFIG_EVA
|
|
/* Set aliases */
|
|
.global __strnlen_user_asm
|
|
.global __strnlen_user_nocheck_asm
|
|
.set __strnlen_user_asm, __strnlen_kernel_asm
|
|
.set __strnlen_user_nocheck_asm, __strnlen_kernel_nocheck_asm
|
|
#endif
|
|
|
|
__BUILD_STRNLEN_ASM kernel
|
|
|
|
#ifdef CONFIG_EVA
|
|
|
|
.set push
|
|
.set eva
|
|
__BUILD_STRNLEN_ASM user
|
|
.set pop
|
|
#endif
|