1#ifndef _ASM_KPROBES_H
2#define _ASM_KPROBES_H
3/*
4 *  Kernel Probes (KProbes)
5 *  include/asm-i386/kprobes.h
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20 *
21 * Copyright (C) IBM Corporation, 2002, 2004
22 *
23 * 2002-Oct	Created by Vamsi Krishna S <vamsi_krishna@in.ibm.com> Kernel
24 *		Probes initial implementation ( includes suggestions from
25 *		Rusty Russell).
26 */
27#include <linux/types.h>
28#include <linux/ptrace.h>
29
30#define  __ARCH_WANT_KPROBES_INSN_SLOT
31
32struct kprobe;
33struct pt_regs;
34
35typedef u8 kprobe_opcode_t;
36#define BREAKPOINT_INSTRUCTION	0xcc
37#define RELATIVEJUMP_INSTRUCTION 0xe9
38#define MAX_INSN_SIZE 16
39#define MAX_STACK_SIZE 64
40#define MIN_STACK_SIZE(ADDR) (((MAX_STACK_SIZE) < \
41	(((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR))) \
42	? (MAX_STACK_SIZE) \
43	: (((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR)))
44
45#define JPROBE_ENTRY(pentry)	(kprobe_opcode_t *)pentry
46#define ARCH_SUPPORTS_KRETPROBES
47#define  ARCH_INACTIVE_KPROBE_COUNT 0
48#define flush_insn_slot(p)	do { } while (0)
49
50void arch_remove_kprobe(struct kprobe *p);
51void kretprobe_trampoline(void);
52
53/* Architecture specific copy of original instruction*/
54struct arch_specific_insn {
55	/* copy of the original instruction */
56	kprobe_opcode_t *insn;
57	/*
58	 * If this flag is not 0, this kprobe can be boost when its
59	 * post_handler and break_handler is not set.
60	 */
61	int boostable;
62};
63
64struct prev_kprobe {
65	struct kprobe *kp;
66	unsigned long status;
67	unsigned long old_eflags;
68	unsigned long saved_eflags;
69};
70
71/* per-cpu kprobe control block */
72struct kprobe_ctlblk {
73	unsigned long kprobe_status;
74	unsigned long kprobe_old_eflags;
75	unsigned long kprobe_saved_eflags;
76	long *jprobe_saved_esp;
77	struct pt_regs jprobe_saved_regs;
78	kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
79	struct prev_kprobe prev_kprobe;
80};
81
82/* trap3/1 are intr gates for kprobes.  So, restore the status of IF,
83 * if necessary, before executing the original int3/1 (trap) handler.
84 */
85static inline void restore_interrupts(struct pt_regs *regs)
86{
87	if (regs->eflags & IF_MASK)
88		local_irq_enable();
89}
90
91extern int kprobe_exceptions_notify(struct notifier_block *self,
92				    unsigned long val, void *data);
93#endif				/* _ASM_KPROBES_H */
94