linux/arch/arm/kernel/kprobes.h
Jon Medhurst aea490299f ARM: kprobes: Make str_pc_offset a constant on ARMv7
The str_pc_offset value is architecturally defined on ARMv7 onwards so
we can make it a compile time constant. This means on Thumb kernels the
runtime checking code isn't needed, which saves us from having to fix it
to work for Thumb.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-07-13 17:32:41 +00:00

62 lines
1.5 KiB
C

/*
* arch/arm/kernel/kprobes.h
*
* Contents moved from arch/arm/include/asm/kprobes.h which is
* Copyright (C) 2006, 2007 Motorola Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*/
#ifndef _ARM_KERNEL_KPROBES_H
#define _ARM_KERNEL_KPROBES_H
/*
* This undefined instruction must be unique and
* reserved solely for kprobes' use.
*/
#define KPROBE_BREAKPOINT_INSTRUCTION 0xe7f001f8
enum kprobe_insn {
INSN_REJECTED,
INSN_GOOD,
INSN_GOOD_NO_SLOT
};
enum kprobe_insn arm_kprobe_decode_insn(kprobe_opcode_t,
struct arch_specific_insn *);
void __init arm_kprobe_decode_init(void);
extern kprobe_check_cc * const kprobe_condition_checks[16];
#if __LINUX_ARM_ARCH__ >= 7
/* str_pc_offset is architecturally defined from ARMv7 onwards */
#define str_pc_offset 8
#define find_str_pc_offset()
#else /* __LINUX_ARM_ARCH__ < 7 */
/* We need a run-time check to determine str_pc_offset */
extern int str_pc_offset;
void __init find_str_pc_offset(void);
#endif
/*
* Test if load/store instructions writeback the address register.
* if P (bit 24) == 0 or W (bit 21) == 1
*/
#define is_writeback(insn) ((insn ^ 0x01000000) & 0x01200000)
#endif /* _ARM_KERNEL_KPROBES_H */