summaryrefslogblamecommitdiff
path: root/include/linux/kprobes.h
blob: 99ddba5a4e009b553a56e2c25b1d89c41154fb8e (plain) (tree) 
1da177e4c3f4













































64f562c6df3c ^



1da177e4c3f4



























































































1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45

46
47
48

49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139













































                                                                             


                                                       


























































































                                                                             
#ifndef _LINUX_KPROBES_H
#define _LINUX_KPROBES_H
/*
 *  Kernel Probes (KProbes)
 *  include/linux/kprobes.h
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 * Copyright (C) IBM Corporation, 2002, 2004
 *
 * 2002-Oct	Created by Vamsi Krishna S <vamsi_krishna@in.ibm.com> Kernel
 *		Probes initial implementation ( includes suggestions from
 *		Rusty Russell).
 * 2004-July	Suparna Bhattacharya <suparna@in.ibm.com> added jumper probes
 *		interface to access function arguments.
 */
#include <linux/config.h>
#include <linux/list.h>
#include <linux/notifier.h>
#include <linux/smp.h>
#include <asm/kprobes.h>

struct kprobe;
struct pt_regs;
typedef int (*kprobe_pre_handler_t) (struct kprobe *, struct pt_regs *);
typedef int (*kprobe_break_handler_t) (struct kprobe *, struct pt_regs *);
typedef void (*kprobe_post_handler_t) (struct kprobe *, struct pt_regs *,
				       unsigned long flags);
typedef int (*kprobe_fault_handler_t) (struct kprobe *, struct pt_regs *,
				       int trapnr);
struct kprobe {
	struct hlist_node hlist;

	/* list of kprobes for multi-handler support */
	struct list_head list;

	/* location of the probe point */
	kprobe_opcode_t *addr;

	/* Called before addr is executed. */
	kprobe_pre_handler_t pre_handler;

	/* Called after addr is executed, unless... */
	kprobe_post_handler_t post_handler;

	/* ... called if executing addr causes a fault (eg. page fault).
	 * Return 1 if it handled fault, otherwise kernel will see it. */
	kprobe_fault_handler_t fault_handler;

	/* ... called if breakpoint trap occurs in probe handler.
	 * Return 1 if it handled break, otherwise kernel will see it. */
	kprobe_break_handler_t break_handler;

	/* Saved opcode (which has been replaced with breakpoint) */
	kprobe_opcode_t opcode;

	/* copy of the original instruction */
	struct arch_specific_insn ainsn;
};

/*
 * Special probe type that uses setjmp-longjmp type tricks to resume
 * execution at a specified entry with a matching prototype corresponding
 * to the probed function - a trick to enable arguments to become
 * accessible seamlessly by probe handling logic.
 * Note:
 * Because of the way compilers allocate stack space for local variables
 * etc upfront, regardless of sub-scopes within a function, this mirroring
 * principle currently works only for probes placed on function entry points.
 */
struct jprobe {
	struct kprobe kp;
	kprobe_opcode_t *entry;	/* probe handling code to jump to */
};

#ifdef CONFIG_KPROBES
/* Locks kprobe: irq must be disabled */
void lock_kprobes(void);
void unlock_kprobes(void);

/* kprobe running now on this CPU? */
static inline int kprobe_running(void)
{
	extern unsigned int kprobe_cpu;
	return kprobe_cpu == smp_processor_id();
}

extern int arch_prepare_kprobe(struct kprobe *p);
extern void arch_copy_kprobe(struct kprobe *p);
extern void arch_remove_kprobe(struct kprobe *p);
extern void show_registers(struct pt_regs *regs);

/* Get the kprobe at this addr (if any).  Must have called lock_kprobes */
struct kprobe *get_kprobe(void *addr);

int register_kprobe(struct kprobe *p);
void unregister_kprobe(struct kprobe *p);
int setjmp_pre_handler(struct kprobe *, struct pt_regs *);
int longjmp_break_handler(struct kprobe *, struct pt_regs *);
int register_jprobe(struct jprobe *p);
void unregister_jprobe(struct jprobe *p);
void jprobe_return(void);

#else
static inline int kprobe_running(void)
{
	return 0;
}
static inline int register_kprobe(struct kprobe *p)
{
	return -ENOSYS;
}
static inline void unregister_kprobe(struct kprobe *p)
{
}
static inline int register_jprobe(struct jprobe *p)
{
	return -ENOSYS;
}
static inline void unregister_jprobe(struct jprobe *p)
{
}
static inline void jprobe_return(void)
{
}
#endif
#endif				/* _LINUX_KPROBES_H */