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kprobes: rename kprobe_enabled to kprobes_all_disarmed
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1da177e4
LT
1#ifndef _LINUX_KPROBES_H
2#define _LINUX_KPROBES_H
3/*
4 * Kernel Probes (KProbes)
5 * include/linux/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 * 2004-July Suparna Bhattacharya <suparna@in.ibm.com> added jumper probes
27 * interface to access function arguments.
b94cce92
HN
28 * 2005-May Hien Nguyen <hien@us.ibm.com> and Jim Keniston
29 * <jkenisto@us.ibm.com> and Prasanna S Panchamukhi
30 * <prasanna@in.ibm.com> added function-return probes.
1da177e4 31 */
36dcd67a 32#include <linux/linkage.h>
1da177e4
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33#include <linux/list.h>
34#include <linux/notifier.h>
35#include <linux/smp.h>
e6584523 36#include <linux/percpu.h>
3516a460
AM
37#include <linux/spinlock.h>
38#include <linux/rcupdate.h>
7a7d1cf9 39#include <linux/mutex.h>
b94cce92 40
00d7c05a 41#ifdef CONFIG_KPROBES
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42#include <asm/kprobes.h>
43
ea32c65c
PP
44/* kprobe_status settings */
45#define KPROBE_HIT_ACTIVE 0x00000001
46#define KPROBE_HIT_SS 0x00000002
47#define KPROBE_REENTER 0x00000004
48#define KPROBE_HIT_SSDONE 0x00000008
49
d0aaff97 50/* Attach to insert probes on any functions which should be ignored*/
36dcd67a 51#define __kprobes __attribute__((__section__(".kprobes.text"))) notrace
dc19835d
MH
52#else /* CONFIG_KPROBES */
53typedef int kprobe_opcode_t;
54struct arch_specific_insn {
55 int dummy;
56};
57#define __kprobes notrace
58#endif /* CONFIG_KPROBES */
d0aaff97 59
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60struct kprobe;
61struct pt_regs;
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62struct kretprobe;
63struct kretprobe_instance;
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64typedef int (*kprobe_pre_handler_t) (struct kprobe *, struct pt_regs *);
65typedef int (*kprobe_break_handler_t) (struct kprobe *, struct pt_regs *);
66typedef void (*kprobe_post_handler_t) (struct kprobe *, struct pt_regs *,
67 unsigned long flags);
68typedef int (*kprobe_fault_handler_t) (struct kprobe *, struct pt_regs *,
69 int trapnr);
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HN
70typedef int (*kretprobe_handler_t) (struct kretprobe_instance *,
71 struct pt_regs *);
72
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73struct kprobe {
74 struct hlist_node hlist;
75
64f562c6
AM
76 /* list of kprobes for multi-handler support */
77 struct list_head list;
78
ea32c65c
PP
79 /*count the number of times this probe was temporarily disarmed */
80 unsigned long nmissed;
81
1da177e4
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82 /* location of the probe point */
83 kprobe_opcode_t *addr;
84
3a872d89 85 /* Allow user to indicate symbol name of the probe point */
9b3af29b 86 const char *symbol_name;
3a872d89
AM
87
88 /* Offset into the symbol */
89 unsigned int offset;
90
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91 /* Called before addr is executed. */
92 kprobe_pre_handler_t pre_handler;
93
94 /* Called after addr is executed, unless... */
95 kprobe_post_handler_t post_handler;
96
cc00e9cf
MH
97 /*
98 * ... called if executing addr causes a fault (eg. page fault).
99 * Return 1 if it handled fault, otherwise kernel will see it.
100 */
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101 kprobe_fault_handler_t fault_handler;
102
cc00e9cf
MH
103 /*
104 * ... called if breakpoint trap occurs in probe handler.
105 * Return 1 if it handled break, otherwise kernel will see it.
106 */
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107 kprobe_break_handler_t break_handler;
108
109 /* Saved opcode (which has been replaced with breakpoint) */
110 kprobe_opcode_t opcode;
111
112 /* copy of the original instruction */
113 struct arch_specific_insn ainsn;
e8386a0c
MH
114
115 /* Indicates various status flags. Protected by kprobe_mutex. */
116 u32 flags;
1da177e4
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117};
118
e8386a0c
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119/* Kprobe status flags */
120#define KPROBE_FLAG_GONE 1 /* breakpoint has already gone */
121
122static inline int kprobe_gone(struct kprobe *p)
123{
124 return p->flags & KPROBE_FLAG_GONE;
125}
126
1da177e4
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127/*
128 * Special probe type that uses setjmp-longjmp type tricks to resume
129 * execution at a specified entry with a matching prototype corresponding
130 * to the probed function - a trick to enable arguments to become
131 * accessible seamlessly by probe handling logic.
132 * Note:
133 * Because of the way compilers allocate stack space for local variables
134 * etc upfront, regardless of sub-scopes within a function, this mirroring
135 * principle currently works only for probes placed on function entry points.
136 */
137struct jprobe {
138 struct kprobe kp;
81eae375 139 void *entry; /* probe handling code to jump to */
1da177e4
LT
140};
141
9e367d85
ME
142/* For backward compatibility with old code using JPROBE_ENTRY() */
143#define JPROBE_ENTRY(handler) (handler)
144
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HN
145/*
146 * Function-return probe -
147 * Note:
148 * User needs to provide a handler function, and initialize maxactive.
149 * maxactive - The maximum number of instances of the probed function that
150 * can be active concurrently.
151 * nmissed - tracks the number of times the probed function's return was
152 * ignored, due to maxactive being too low.
153 *
154 */
155struct kretprobe {
156 struct kprobe kp;
157 kretprobe_handler_t handler;
f47cd9b5 158 kretprobe_handler_t entry_handler;
b94cce92
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159 int maxactive;
160 int nmissed;
f47cd9b5 161 size_t data_size;
b94cce92 162 struct hlist_head free_instances;
ef53d9c5 163 spinlock_t lock;
b94cce92
HN
164};
165
166struct kretprobe_instance {
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HN
167 struct hlist_node hlist;
168 struct kretprobe *rp;
802eae7c
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169 kprobe_opcode_t *ret_addr;
170 struct task_struct *task;
f47cd9b5 171 char data[0];
b94cce92
HN
172};
173
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MH
174struct kretprobe_blackpoint {
175 const char *name;
176 void *addr;
177};
3d8d996e
SD
178
179struct kprobe_blackpoint {
180 const char *name;
181 unsigned long start_addr;
182 unsigned long range;
183};
184
dc19835d
MH
185#ifdef CONFIG_KPROBES
186DECLARE_PER_CPU(struct kprobe *, current_kprobe);
187DECLARE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
188
b1801812
IM
189/*
190 * For #ifdef avoidance:
191 */
192static inline int kprobes_built_in(void)
193{
194 return 1;
195}
196
dc19835d
MH
197#ifdef CONFIG_KRETPROBES
198extern void arch_prepare_kretprobe(struct kretprobe_instance *ri,
199 struct pt_regs *regs);
200extern int arch_trampoline_kprobe(struct kprobe *p);
201#else /* CONFIG_KRETPROBES */
202static inline void arch_prepare_kretprobe(struct kretprobe *rp,
203 struct pt_regs *regs)
204{
205}
206static inline int arch_trampoline_kprobe(struct kprobe *p)
207{
208 return 0;
209}
210#endif /* CONFIG_KRETPROBES */
211
f438d914
MH
212extern struct kretprobe_blackpoint kretprobe_blacklist[];
213
0f95b7fc
AM
214static inline void kretprobe_assert(struct kretprobe_instance *ri,
215 unsigned long orig_ret_address, unsigned long trampoline_address)
216{
217 if (!orig_ret_address || (orig_ret_address == trampoline_address)) {
218 printk("kretprobe BUG!: Processing kretprobe %p @ %p\n",
219 ri->rp, ri->rp->kp.addr);
220 BUG();
221 }
222}
223
8c1c9356
AM
224#ifdef CONFIG_KPROBES_SANITY_TEST
225extern int init_test_probes(void);
226#else
227static inline int init_test_probes(void)
228{
229 return 0;
230}
231#endif /* CONFIG_KPROBES_SANITY_TEST */
232
1da177e4 233extern int arch_prepare_kprobe(struct kprobe *p);
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234extern void arch_arm_kprobe(struct kprobe *p);
235extern void arch_disarm_kprobe(struct kprobe *p);
6772926b 236extern int arch_init_kprobes(void);
1da177e4 237extern void show_registers(struct pt_regs *regs);
9ec4b1f3 238extern kprobe_opcode_t *get_insn_slot(void);
b4c6c34a 239extern void free_insn_slot(kprobe_opcode_t *slot, int dirty);
bf8d5c52 240extern void kprobes_inc_nmissed_count(struct kprobe *p);
1da177e4 241
d217d545 242/* Get the kprobe at this addr (if any) - called with preemption disabled */
1da177e4 243struct kprobe *get_kprobe(void *addr);
ef53d9c5
S
244void kretprobe_hash_lock(struct task_struct *tsk,
245 struct hlist_head **head, unsigned long *flags);
246void kretprobe_hash_unlock(struct task_struct *tsk, unsigned long *flags);
b94cce92 247struct hlist_head * kretprobe_inst_table_head(struct task_struct *tsk);
1da177e4 248
e6584523
AM
249/* kprobe_running() will just return the current_kprobe on this CPU */
250static inline struct kprobe *kprobe_running(void)
251{
252 return (__get_cpu_var(current_kprobe));
253}
254
255static inline void reset_current_kprobe(void)
256{
257 __get_cpu_var(current_kprobe) = NULL;
258}
259
260static inline struct kprobe_ctlblk *get_kprobe_ctlblk(void)
261{
262 return (&__get_cpu_var(kprobe_ctlblk));
263}
264
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265int register_kprobe(struct kprobe *p);
266void unregister_kprobe(struct kprobe *p);
9861668f
MH
267int register_kprobes(struct kprobe **kps, int num);
268void unregister_kprobes(struct kprobe **kps, int num);
1da177e4
LT
269int setjmp_pre_handler(struct kprobe *, struct pt_regs *);
270int longjmp_break_handler(struct kprobe *, struct pt_regs *);
271int register_jprobe(struct jprobe *p);
272void unregister_jprobe(struct jprobe *p);
26b31c19
MH
273int register_jprobes(struct jprobe **jps, int num);
274void unregister_jprobes(struct jprobe **jps, int num);
1da177e4 275void jprobe_return(void);
3d7e3382 276unsigned long arch_deref_entry_point(void *);
1da177e4 277
b94cce92
HN
278int register_kretprobe(struct kretprobe *rp);
279void unregister_kretprobe(struct kretprobe *rp);
4a296e07
MH
280int register_kretprobes(struct kretprobe **rps, int num);
281void unregister_kretprobes(struct kretprobe **rps, int num);
b94cce92 282
b94cce92 283void kprobe_flush_task(struct task_struct *tk);
99219a3f 284void recycle_rp_inst(struct kretprobe_instance *ri, struct hlist_head *head);
8c1c9356 285
b1801812 286#else /* !CONFIG_KPROBES: */
00d7c05a 287
b1801812
IM
288static inline int kprobes_built_in(void)
289{
290 return 0;
291}
292static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
293{
294 return 0;
295}
785656a4
AS
296static inline struct kprobe *get_kprobe(void *addr)
297{
298 return NULL;
299}
e6584523 300static inline struct kprobe *kprobe_running(void)
1da177e4 301{
e6584523 302 return NULL;
1da177e4
LT
303}
304static inline int register_kprobe(struct kprobe *p)
305{
306 return -ENOSYS;
307}
9861668f
MH
308static inline int register_kprobes(struct kprobe **kps, int num)
309{
310 return -ENOSYS;
311}
1da177e4
LT
312static inline void unregister_kprobe(struct kprobe *p)
313{
314}
9861668f
MH
315static inline void unregister_kprobes(struct kprobe **kps, int num)
316{
317}
1da177e4
LT
318static inline int register_jprobe(struct jprobe *p)
319{
320 return -ENOSYS;
321}
26b31c19
MH
322static inline int register_jprobes(struct jprobe **jps, int num)
323{
324 return -ENOSYS;
325}
1da177e4
LT
326static inline void unregister_jprobe(struct jprobe *p)
327{
328}
26b31c19
MH
329static inline void unregister_jprobes(struct jprobe **jps, int num)
330{
331}
1da177e4
LT
332static inline void jprobe_return(void)
333{
334}
b94cce92
HN
335static inline int register_kretprobe(struct kretprobe *rp)
336{
337 return -ENOSYS;
338}
4a296e07
MH
339static inline int register_kretprobes(struct kretprobe **rps, int num)
340{
341 return -ENOSYS;
342}
b94cce92
HN
343static inline void unregister_kretprobe(struct kretprobe *rp)
344{
345}
4a296e07
MH
346static inline void unregister_kretprobes(struct kretprobe **rps, int num)
347{
348}
b94cce92
HN
349static inline void kprobe_flush_task(struct task_struct *tk)
350{
351}
b1801812
IM
352#endif /* CONFIG_KPROBES */
353#endif /* _LINUX_KPROBES_H */