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.
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.
31 */
32 #include <linux/list.h>
33 #include <linux/notifier.h>
34 #include <linux/smp.h>
35 #include <linux/percpu.h>
36 #include <linux/spinlock.h>
37 #include <linux/rcupdate.h>
38 #include <linux/mutex.h>
39
40 #ifdef CONFIG_KPROBES
41 #include <asm/kprobes.h>
42
43 /* kprobe_status settings */
44 #define KPROBE_HIT_ACTIVE 0x00000001
45 #define KPROBE_HIT_SS 0x00000002
46 #define KPROBE_REENTER 0x00000004
47 #define KPROBE_HIT_SSDONE 0x00000008
48
49 /* Attach to insert probes on any functions which should be ignored*/
50 #define __kprobes __attribute__((__section__(".kprobes.text")))
51
52 struct kprobe;
53 struct pt_regs;
54 struct kretprobe;
55 struct kretprobe_instance;
56 typedef int (*kprobe_pre_handler_t) (struct kprobe *, struct pt_regs *);
57 typedef int (*kprobe_break_handler_t) (struct kprobe *, struct pt_regs *);
58 typedef void (*kprobe_post_handler_t) (struct kprobe *, struct pt_regs *,
59 unsigned long flags);
60 typedef int (*kprobe_fault_handler_t) (struct kprobe *, struct pt_regs *,
61 int trapnr);
62 typedef int (*kretprobe_handler_t) (struct kretprobe_instance *,
63 struct pt_regs *);
64
65 struct kprobe {
66 struct hlist_node hlist;
67
68 /* list of kprobes for multi-handler support */
69 struct list_head list;
70
71 /* Indicates that the corresponding module has been ref counted */
72 unsigned int mod_refcounted;
73
74 /*count the number of times this probe was temporarily disarmed */
75 unsigned long nmissed;
76
77 /* location of the probe point */
78 kprobe_opcode_t *addr;
79
80 /* Allow user to indicate symbol name of the probe point */
81 const char *symbol_name;
82
83 /* Offset into the symbol */
84 unsigned int offset;
85
86 /* Called before addr is executed. */
87 kprobe_pre_handler_t pre_handler;
88
89 /* Called after addr is executed, unless... */
90 kprobe_post_handler_t post_handler;
91
92 /* ... called if executing addr causes a fault (eg. page fault).
93 * Return 1 if it handled fault, otherwise kernel will see it. */
94 kprobe_fault_handler_t fault_handler;
95
96 /* ... called if breakpoint trap occurs in probe handler.
97 * Return 1 if it handled break, otherwise kernel will see it. */
98 kprobe_break_handler_t break_handler;
99
100 /* Saved opcode (which has been replaced with breakpoint) */
101 kprobe_opcode_t opcode;
102
103 /* copy of the original instruction */
104 struct arch_specific_insn ainsn;
105 };
106
107 /*
108 * Special probe type that uses setjmp-longjmp type tricks to resume
109 * execution at a specified entry with a matching prototype corresponding
110 * to the probed function - a trick to enable arguments to become
111 * accessible seamlessly by probe handling logic.
112 * Note:
113 * Because of the way compilers allocate stack space for local variables
114 * etc upfront, regardless of sub-scopes within a function, this mirroring
115 * principle currently works only for probes placed on function entry points.
116 */
117 struct jprobe {
118 struct kprobe kp;
119 void *entry; /* probe handling code to jump to */
120 };
121
122 /* For backward compatibility with old code using JPROBE_ENTRY() */
123 #define JPROBE_ENTRY(handler) (handler)
124
125 DECLARE_PER_CPU(struct kprobe *, current_kprobe);
126 DECLARE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
127
128 #ifdef CONFIG_KRETPROBES
129 extern void arch_prepare_kretprobe(struct kretprobe_instance *ri,
130 struct pt_regs *regs);
131 extern int arch_trampoline_kprobe(struct kprobe *p);
132 #else /* CONFIG_KRETPROBES */
133 static inline void arch_prepare_kretprobe(struct kretprobe *rp,
134 struct pt_regs *regs)
135 {
136 }
137 static inline int arch_trampoline_kprobe(struct kprobe *p)
138 {
139 return 0;
140 }
141 #endif /* CONFIG_KRETPROBES */
142 /*
143 * Function-return probe -
144 * Note:
145 * User needs to provide a handler function, and initialize maxactive.
146 * maxactive - The maximum number of instances of the probed function that
147 * can be active concurrently.
148 * nmissed - tracks the number of times the probed function's return was
149 * ignored, due to maxactive being too low.
150 *
151 */
152 struct kretprobe {
153 struct kprobe kp;
154 kretprobe_handler_t handler;
155 kretprobe_handler_t entry_handler;
156 int maxactive;
157 int nmissed;
158 size_t data_size;
159 struct hlist_head free_instances;
160 struct hlist_head used_instances;
161 };
162
163 struct kretprobe_instance {
164 struct hlist_node uflist; /* either on free list or used list */
165 struct hlist_node hlist;
166 struct kretprobe *rp;
167 kprobe_opcode_t *ret_addr;
168 struct task_struct *task;
169 char data[0];
170 };
171
172 struct kretprobe_blackpoint {
173 const char *name;
174 void *addr;
175 };
176 extern struct kretprobe_blackpoint kretprobe_blacklist[];
177
178 static inline void kretprobe_assert(struct kretprobe_instance *ri,
179 unsigned long orig_ret_address, unsigned long trampoline_address)
180 {
181 if (!orig_ret_address || (orig_ret_address == trampoline_address)) {
182 printk("kretprobe BUG!: Processing kretprobe %p @ %p\n",
183 ri->rp, ri->rp->kp.addr);
184 BUG();
185 }
186 }
187
188 #ifdef CONFIG_KPROBES_SANITY_TEST
189 extern int init_test_probes(void);
190 #else
191 static inline int init_test_probes(void)
192 {
193 return 0;
194 }
195 #endif /* CONFIG_KPROBES_SANITY_TEST */
196
197 extern spinlock_t kretprobe_lock;
198 extern struct mutex kprobe_mutex;
199 extern int arch_prepare_kprobe(struct kprobe *p);
200 extern void arch_arm_kprobe(struct kprobe *p);
201 extern void arch_disarm_kprobe(struct kprobe *p);
202 extern int arch_init_kprobes(void);
203 extern void show_registers(struct pt_regs *regs);
204 extern kprobe_opcode_t *get_insn_slot(void);
205 extern void free_insn_slot(kprobe_opcode_t *slot, int dirty);
206 extern void kprobes_inc_nmissed_count(struct kprobe *p);
207
208 /* Get the kprobe at this addr (if any) - called with preemption disabled */
209 struct kprobe *get_kprobe(void *addr);
210 struct hlist_head * kretprobe_inst_table_head(struct task_struct *tsk);
211
212 /* kprobe_running() will just return the current_kprobe on this CPU */
213 static inline struct kprobe *kprobe_running(void)
214 {
215 return (__get_cpu_var(current_kprobe));
216 }
217
218 static inline void reset_current_kprobe(void)
219 {
220 __get_cpu_var(current_kprobe) = NULL;
221 }
222
223 static inline struct kprobe_ctlblk *get_kprobe_ctlblk(void)
224 {
225 return (&__get_cpu_var(kprobe_ctlblk));
226 }
227
228 int register_kprobe(struct kprobe *p);
229 void unregister_kprobe(struct kprobe *p);
230 int setjmp_pre_handler(struct kprobe *, struct pt_regs *);
231 int longjmp_break_handler(struct kprobe *, struct pt_regs *);
232 int register_jprobe(struct jprobe *p);
233 void unregister_jprobe(struct jprobe *p);
234 void jprobe_return(void);
235 unsigned long arch_deref_entry_point(void *);
236
237 int register_kretprobe(struct kretprobe *rp);
238 void unregister_kretprobe(struct kretprobe *rp);
239
240 void kprobe_flush_task(struct task_struct *tk);
241 void recycle_rp_inst(struct kretprobe_instance *ri, struct hlist_head *head);
242
243 #else /* CONFIG_KPROBES */
244
245 #define __kprobes /**/
246 struct jprobe;
247 struct kretprobe;
248
249 static inline struct kprobe *kprobe_running(void)
250 {
251 return NULL;
252 }
253 static inline int register_kprobe(struct kprobe *p)
254 {
255 return -ENOSYS;
256 }
257 static inline void unregister_kprobe(struct kprobe *p)
258 {
259 }
260 static inline int register_jprobe(struct jprobe *p)
261 {
262 return -ENOSYS;
263 }
264 static inline void unregister_jprobe(struct jprobe *p)
265 {
266 }
267 static inline void jprobe_return(void)
268 {
269 }
270 static inline int register_kretprobe(struct kretprobe *rp)
271 {
272 return -ENOSYS;
273 }
274 static inline void unregister_kretprobe(struct kretprobe *rp)
275 {
276 }
277 static inline void kprobe_flush_task(struct task_struct *tk)
278 {
279 }
280 #endif /* CONFIG_KPROBES */
281 #endif /* _LINUX_KPROBES_H */
282
|
This page was automatically generated by the
LXR engine.
|