[mirror_ubuntu-zesty-kernel.git] / include / linux / kprobes.h

#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.
 * 2005-May	Hien Nguyen <hien@us.ibm.com> and Jim Keniston
 *		<jkenisto@us.ibm.com>  and Prasanna S Panchamukhi
 *		<prasanna@in.ibm.com> added function-return probes.
 */
#include <linux/compiler.h>	/* for __kprobes */
#include <linux/linkage.h>
#include <linux/list.h>
#include <linux/notifier.h>
#include <linux/smp.h>
#include <linux/bug.h>
#include <linux/percpu.h>
#include <linux/spinlock.h>
#include <linux/rcupdate.h>
#include <linux/mutex.h>
#include <linux/ftrace.h>

#ifdef CONFIG_KPROBES
#include <asm/kprobes.h>

/* kprobe_status settings */
#define KPROBE_HIT_ACTIVE	0x00000001
#define KPROBE_HIT_SS		0x00000002
#define KPROBE_REENTER		0x00000004
#define KPROBE_HIT_SSDONE	0x00000008

#else /* CONFIG_KPROBES */
typedef int kprobe_opcode_t;
struct arch_specific_insn {
	int dummy;
};
#endif /* CONFIG_KPROBES */

struct kprobe;
struct pt_regs;
struct kretprobe;
struct kretprobe_instance;
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);
typedef int (*kretprobe_handler_t) (struct kretprobe_instance *,
				    struct pt_regs *);

struct kprobe {
	struct hlist_node hlist;

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

	/*count the number of times this probe was temporarily disarmed */
	unsigned long nmissed;

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

	/* Allow user to indicate symbol name of the probe point */
	const char *symbol_name;

	/* Offset into the symbol */
	unsigned int offset;

	/* 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;

	/*
	 * Indicates various status flags.
	 * Protected by kprobe_mutex after this kprobe is registered.
	 */
	u32 flags;
};

/* Kprobe status flags */
#define KPROBE_FLAG_GONE	1 /* breakpoint has already gone */
#define KPROBE_FLAG_DISABLED	2 /* probe is temporarily disabled */
#define KPROBE_FLAG_OPTIMIZED	4 /*
				   * probe is really optimized.
				   * NOTE:
				   * this flag is only for optimized_kprobe.
				   */
#define KPROBE_FLAG_FTRACE	8 /* probe is using ftrace */

/* Has this kprobe gone ? */
static inline int kprobe_gone(struct kprobe *p)
{
	return p->flags & KPROBE_FLAG_GONE;
}

/* Is this kprobe disabled ? */
static inline int kprobe_disabled(struct kprobe *p)
{
	return p->flags & (KPROBE_FLAG_DISABLED | KPROBE_FLAG_GONE);
}

/* Is this kprobe really running optimized path ? */
static inline int kprobe_optimized(struct kprobe *p)
{
	return p->flags & KPROBE_FLAG_OPTIMIZED;
}

/* Is this kprobe uses ftrace ? */
static inline int kprobe_ftrace(struct kprobe *p)
{
	return p->flags & KPROBE_FLAG_FTRACE;
}

/*
 * 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;
	void *entry;	/* probe handling code to jump to */
};

/* For backward compatibility with old code using JPROBE_ENTRY() */
#define JPROBE_ENTRY(handler)	(handler)

/*
 * Function-return probe -
 * Note:
 * User needs to provide a handler function, and initialize maxactive.
 * maxactive - The maximum number of instances of the probed function that
 * can be active concurrently.
 * nmissed - tracks the number of times the probed function's return was
 * ignored, due to maxactive being too low.
 *
 */
struct kretprobe {
	struct kprobe kp;
	kretprobe_handler_t handler;
	kretprobe_handler_t entry_handler;
	int maxactive;
	int nmissed;
	size_t data_size;
	struct hlist_head free_instances;
	raw_spinlock_t lock;
};

struct kretprobe_instance {
	struct hlist_node hlist;
	struct kretprobe *rp;
	kprobe_opcode_t *ret_addr;
	struct task_struct *task;
	char data[0];
};

struct kretprobe_blackpoint {
	const char *name;
	void *addr;
};

struct kprobe_blacklist_entry {
	struct list_head list;
	unsigned long start_addr;
	unsigned long end_addr;
};

#ifdef CONFIG_KPROBES
DECLARE_PER_CPU(struct kprobe *, current_kprobe);
DECLARE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);

/*
 * For #ifdef avoidance:
 */
static inline int kprobes_built_in(void)
{
	return 1;
}

#ifdef CONFIG_KRETPROBES
extern void arch_prepare_kretprobe(struct kretprobe_instance *ri,
				   struct pt_regs *regs);
extern int arch_trampoline_kprobe(struct kprobe *p);
#else /* CONFIG_KRETPROBES */
static inline void arch_prepare_kretprobe(struct kretprobe *rp,
					struct pt_regs *regs)
{
}
static inline int arch_trampoline_kprobe(struct kprobe *p)
{
	return 0;
}
#endif /* CONFIG_KRETPROBES */

extern struct kretprobe_blackpoint kretprobe_blacklist[];

static inline void kretprobe_assert(struct kretprobe_instance *ri,
	unsigned long orig_ret_address, unsigned long trampoline_address)
{
	if (!orig_ret_address || (orig_ret_address == trampoline_address)) {
		printk("kretprobe BUG!: Processing kretprobe %p @ %p\n",
				ri->rp, ri->rp->kp.addr);
		BUG();
	}
}

#ifdef CONFIG_KPROBES_SANITY_TEST
extern int init_test_probes(void);
#else
static inline int init_test_probes(void)
{
	return 0;
}
#endif /* CONFIG_KPROBES_SANITY_TEST */

extern int arch_prepare_kprobe(struct kprobe *p);
extern void arch_arm_kprobe(struct kprobe *p);
extern void arch_disarm_kprobe(struct kprobe *p);
extern int arch_init_kprobes(void);
extern void show_registers(struct pt_regs *regs);
extern void kprobes_inc_nmissed_count(struct kprobe *p);
extern bool arch_within_kprobe_blacklist(unsigned long addr);

extern bool within_kprobe_blacklist(unsigned long addr);

struct kprobe_insn_cache {
	struct mutex mutex;
	void *(*alloc)(void);	/* allocate insn page */
	void (*free)(void *);	/* free insn page */
	struct list_head pages; /* list of kprobe_insn_page */
	size_t insn_size;	/* size of instruction slot */
	int nr_garbage;
};

extern kprobe_opcode_t *__get_insn_slot(struct kprobe_insn_cache *c);
extern void __free_insn_slot(struct kprobe_insn_cache *c,
			     kprobe_opcode_t *slot, int dirty);

#define DEFINE_INSN_CACHE_OPS(__name)					\
extern struct kprobe_insn_cache kprobe_##__name##_slots;		\
									\
static inline kprobe_opcode_t *get_##__name##_slot(void)		\
{									\
	return __get_insn_slot(&kprobe_##__name##_slots);		\
}									\
									\
static inline void free_##__name##_slot(kprobe_opcode_t *slot, int dirty)\
{									\
	__free_insn_slot(&kprobe_##__name##_slots, slot, dirty);	\
}									\

DEFINE_INSN_CACHE_OPS(insn);

#ifdef CONFIG_OPTPROBES
/*
 * Internal structure for direct jump optimized probe
 */
struct optimized_kprobe {
	struct kprobe kp;
	struct list_head list;	/* list for optimizing queue */
	struct arch_optimized_insn optinsn;
};

/* Architecture dependent functions for direct jump optimization */
extern int arch_prepared_optinsn(struct arch_optimized_insn *optinsn);
extern int arch_check_optimized_kprobe(struct optimized_kprobe *op);
extern int arch_prepare_optimized_kprobe(struct optimized_kprobe *op,
					 struct kprobe *orig);
extern void arch_remove_optimized_kprobe(struct optimized_kprobe *op);
extern void arch_optimize_kprobes(struct list_head *oplist);
extern void arch_unoptimize_kprobes(struct list_head *oplist,
				    struct list_head *done_list);
extern void arch_unoptimize_kprobe(struct optimized_kprobe *op);
extern int arch_within_optimized_kprobe(struct optimized_kprobe *op,
					unsigned long addr);

extern void opt_pre_handler(struct kprobe *p, struct pt_regs *regs);

DEFINE_INSN_CACHE_OPS(optinsn);

#ifdef CONFIG_SYSCTL
extern int sysctl_kprobes_optimization;
extern int proc_kprobes_optimization_handler(struct ctl_table *table,
					     int write, void __user *buffer,
					     size_t *length, loff_t *ppos);
#endif

#endif /* CONFIG_OPTPROBES */
#ifdef CONFIG_KPROBES_ON_FTRACE
extern void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
				  struct ftrace_ops *ops, struct pt_regs *regs);
extern int arch_prepare_kprobe_ftrace(struct kprobe *p);
#endif

int arch_check_ftrace_location(struct kprobe *p);

/* Get the kprobe at this addr (if any) - called with preemption disabled */
struct kprobe *get_kprobe(void *addr);
void kretprobe_hash_lock(struct task_struct *tsk,
			 struct hlist_head **head, unsigned long *flags);
void kretprobe_hash_unlock(struct task_struct *tsk, unsigned long *flags);
struct hlist_head * kretprobe_inst_table_head(struct task_struct *tsk);

/* kprobe_running() will just return the current_kprobe on this CPU */
static inline struct kprobe *kprobe_running(void)
{
	return (__this_cpu_read(current_kprobe));
}

static inline void reset_current_kprobe(void)
{
	__this_cpu_write(current_kprobe, NULL);
}

static inline struct kprobe_ctlblk *get_kprobe_ctlblk(void)
{
	return this_cpu_ptr(&kprobe_ctlblk);
}

int register_kprobe(struct kprobe *p);
void unregister_kprobe(struct kprobe *p);
int register_kprobes(struct kprobe **kps, int num);
void unregister_kprobes(struct kprobe **kps, int num);
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);
int register_jprobes(struct jprobe **jps, int num);
void unregister_jprobes(struct jprobe **jps, int num);
void jprobe_return(void);
unsigned long arch_deref_entry_point(void *);

int register_kretprobe(struct kretprobe *rp);
void unregister_kretprobe(struct kretprobe *rp);
int register_kretprobes(struct kretprobe **rps, int num);
void unregister_kretprobes(struct kretprobe **rps, int num);

void kprobe_flush_task(struct task_struct *tk);
void recycle_rp_inst(struct kretprobe_instance *ri, struct hlist_head *head);

int disable_kprobe(struct kprobe *kp);
int enable_kprobe(struct kprobe *kp);

void dump_kprobe(struct kprobe *kp);

#else /* !CONFIG_KPROBES: */

static inline int kprobes_built_in(void)
{
	return 0;
}
static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
{
	return 0;
}
static inline struct kprobe *get_kprobe(void *addr)
{
	return NULL;
}
static inline struct kprobe *kprobe_running(void)
{
	return NULL;
}
static inline int register_kprobe(struct kprobe *p)
{
	return -ENOSYS;
}
static inline int register_kprobes(struct kprobe **kps, int num)
{
	return -ENOSYS;
}
static inline void unregister_kprobe(struct kprobe *p)
{
}
static inline void unregister_kprobes(struct kprobe **kps, int num)
{
}
static inline int register_jprobe(struct jprobe *p)
{
	return -ENOSYS;
}
static inline int register_jprobes(struct jprobe **jps, int num)
{
	return -ENOSYS;
}
static inline void unregister_jprobe(struct jprobe *p)
{
}
static inline void unregister_jprobes(struct jprobe **jps, int num)
{
}
static inline void jprobe_return(void)
{
}
static inline int register_kretprobe(struct kretprobe *rp)
{
	return -ENOSYS;
}
static inline int register_kretprobes(struct kretprobe **rps, int num)
{
	return -ENOSYS;
}
static inline void unregister_kretprobe(struct kretprobe *rp)
{
}
static inline void unregister_kretprobes(struct kretprobe **rps, int num)
{
}
static inline void kprobe_flush_task(struct task_struct *tk)
{
}
static inline int disable_kprobe(struct kprobe *kp)
{
	return -ENOSYS;
}
static inline int enable_kprobe(struct kprobe *kp)
{
	return -ENOSYS;
}
#endif /* CONFIG_KPROBES */
static inline int disable_kretprobe(struct kretprobe *rp)
{
	return disable_kprobe(&rp->kp);
}
static inline int enable_kretprobe(struct kretprobe *rp)
{
	return enable_kprobe(&rp->kp);
}
static inline int disable_jprobe(struct jprobe *jp)
{
	return disable_kprobe(&jp->kp);
}
static inline int enable_jprobe(struct jprobe *jp)
{
	return enable_kprobe(&jp->kp);
}

#ifdef CONFIG_KPROBES
/*
 * Blacklist ganerating macro. Specify functions which is not probed
 * by using this macro.
 */
#define __NOKPROBE_SYMBOL(fname)			\
static unsigned long __used				\
	__attribute__((section("_kprobe_blacklist")))	\
	_kbl_addr_##fname = (unsigned long)fname;
#define NOKPROBE_SYMBOL(fname)	__NOKPROBE_SYMBOL(fname)
#else
#define NOKPROBE_SYMBOL(fname)
#endif

#endif /* _LINUX_KPROBES_H */
Commit	Line	Data
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	*/
324670b6	32	#include <linux/compiler.h> /* for __kprobes */
36dcd67a	33	#include <linux/linkage.h>
1da177e4 LT	34	#include <linux/list.h>
	35	#include <linux/notifier.h>
	36	#include <linux/smp.h>
187f1882	37	#include <linux/bug.h>
e6584523	38	#include <linux/percpu.h>
3516a460 AM	39	#include <linux/spinlock.h>
3516a460 AM	40	#include <linux/rcupdate.h>
7a7d1cf9	41	#include <linux/mutex.h>
ae6aa16f	42	#include <linux/ftrace.h>
b94cce92	43
00d7c05a	44	#ifdef CONFIG_KPROBES
1da177e4 LT	45	#include <asm/kprobes.h>
1da177e4 LT	46
ea32c65c PP	47	/* kprobe_status settings */
	48	#define KPROBE_HIT_ACTIVE 0x00000001
	49	#define KPROBE_HIT_SS 0x00000002
	50	#define KPROBE_REENTER 0x00000004
	51	#define KPROBE_HIT_SSDONE 0x00000008
	52
dc19835d MH	53	#else /* CONFIG_KPROBES */
	54	typedef int kprobe_opcode_t;
	55	struct arch_specific_insn {
	56	int dummy;
	57	};
dc19835d	58	#endif /* CONFIG_KPROBES */
d0aaff97	59
1da177e4 LT	60	struct kprobe;
1da177e4 LT	61	struct pt_regs;
b94cce92 HN	62	struct kretprobe;
b94cce92 HN	63	struct kretprobe_instance;
1da177e4 LT	64	typedef int (kprobe_pre_handler_t) (struct kprobe , struct pt_regs *);
	65	typedef int (kprobe_break_handler_t) (struct kprobe , struct pt_regs *);
	66	typedef void (kprobe_post_handler_t) (struct kprobe , struct pt_regs *,
	67	unsigned long flags);
	68	typedef int (kprobe_fault_handler_t) (struct kprobe , struct pt_regs *,
	69	int trapnr);
b94cce92 HN	70	typedef int (kretprobe_handler_t) (struct kretprobe_instance ,
	71	struct pt_regs *);
	72
1da177e4 LT	73	struct 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 LT	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
1da177e4 LT	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	*/
1da177e4 LT	101	kprobe_fault_handler_t fault_handler;
1da177e4 LT	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	*/
1da177e4 LT	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	114
de5bd88d MH	115	/*
	116	* Indicates various status flags.
	117	* Protected by kprobe_mutex after this kprobe is registered.
	118	*/
e8386a0c	119	u32 flags;
1da177e4 LT	120	};
1da177e4 LT	121
e8386a0c MH	122	/* Kprobe status flags */
e8386a0c MH	123	#define KPROBE_FLAG_GONE 1 /* breakpoint has already gone */
de5bd88d	124	#define KPROBE_FLAG_DISABLED 2 /* probe is temporarily disabled */
afd66255 MH	125	#define KPROBE_FLAG_OPTIMIZED 4 /*
	126	* probe is really optimized.
	127	* NOTE:
	128	* this flag is only for optimized_kprobe.
	129	*/
ae6aa16f	130	#define KPROBE_FLAG_FTRACE 8 /* probe is using ftrace */
e8386a0c	131
de5bd88d	132	/* Has this kprobe gone ? */
e8386a0c MH	133	static inline int kprobe_gone(struct kprobe *p)
	134	{
	135	return p->flags & KPROBE_FLAG_GONE;
	136	}
	137
de5bd88d MH	138	/* Is this kprobe disabled ? */
	139	static inline int kprobe_disabled(struct kprobe *p)
	140	{
	141	return p->flags & (KPROBE_FLAG_DISABLED \| KPROBE_FLAG_GONE);
	142	}
afd66255 MH	143
	144	/* Is this kprobe really running optimized path ? */
	145	static inline int kprobe_optimized(struct kprobe *p)
	146	{
	147	return p->flags & KPROBE_FLAG_OPTIMIZED;
	148	}
ae6aa16f MH	149
	150	/* Is this kprobe uses ftrace ? */
	151	static inline int kprobe_ftrace(struct kprobe *p)
	152	{
	153	return p->flags & KPROBE_FLAG_FTRACE;
	154	}
	155
1da177e4 LT	156	/*
	157	* Special probe type that uses setjmp-longjmp type tricks to resume
	158	* execution at a specified entry with a matching prototype corresponding
	159	* to the probed function - a trick to enable arguments to become
	160	* accessible seamlessly by probe handling logic.
	161	* Note:
	162	* Because of the way compilers allocate stack space for local variables
	163	* etc upfront, regardless of sub-scopes within a function, this mirroring
	164	* principle currently works only for probes placed on function entry points.
	165	*/
	166	struct jprobe {
	167	struct kprobe kp;
81eae375	168	void entry; / probe handling code to jump to */
1da177e4 LT	169	};
1da177e4 LT	170
9e367d85 ME	171	/* For backward compatibility with old code using JPROBE_ENTRY() */
	172	#define JPROBE_ENTRY(handler) (handler)
	173
b94cce92 HN	174	/*
	175	* Function-return probe -
	176	* Note:
	177	* User needs to provide a handler function, and initialize maxactive.
	178	* maxactive - The maximum number of instances of the probed function that
	179	* can be active concurrently.
	180	* nmissed - tracks the number of times the probed function's return was
	181	* ignored, due to maxactive being too low.
	182	*
	183	*/
	184	struct kretprobe {
	185	struct kprobe kp;
	186	kretprobe_handler_t handler;
f47cd9b5	187	kretprobe_handler_t entry_handler;
b94cce92 HN	188	int maxactive;
b94cce92 HN	189	int nmissed;
f47cd9b5	190	size_t data_size;
b94cce92	191	struct hlist_head free_instances;
ec484608	192	raw_spinlock_t lock;
b94cce92 HN	193	};
	194
	195	struct kretprobe_instance {
b94cce92 HN	196	struct hlist_node hlist;
b94cce92 HN	197	struct kretprobe *rp;
802eae7c RL	198	kprobe_opcode_t *ret_addr;
802eae7c RL	199	struct task_struct *task;
f47cd9b5	200	char data[0];
b94cce92 HN	201	};
b94cce92 HN	202
f438d914 MH	203	struct kretprobe_blackpoint {
	204	const char *name;
	205	void *addr;
	206	};
3d8d996e	207
376e2424 MH	208	struct kprobe_blacklist_entry {
376e2424 MH	209	struct list_head list;
3d8d996e	210	unsigned long start_addr;
376e2424	211	unsigned long end_addr;
3d8d996e SD	212	};
3d8d996e SD	213
dc19835d MH	214	#ifdef CONFIG_KPROBES
	215	DECLARE_PER_CPU(struct kprobe *, current_kprobe);
	216	DECLARE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
	217
b1801812 IM	218	/*
	219	* For #ifdef avoidance:
	220	*/
	221	static inline int kprobes_built_in(void)
	222	{
	223	return 1;
	224	}
	225
dc19835d MH	226	#ifdef CONFIG_KRETPROBES
	227	extern void arch_prepare_kretprobe(struct kretprobe_instance *ri,
	228	struct pt_regs *regs);
	229	extern int arch_trampoline_kprobe(struct kprobe *p);
	230	#else /* CONFIG_KRETPROBES */
	231	static inline void arch_prepare_kretprobe(struct kretprobe *rp,
	232	struct pt_regs *regs)
	233	{
	234	}
	235	static inline int arch_trampoline_kprobe(struct kprobe *p)
	236	{
	237	return 0;
	238	}
	239	#endif /* CONFIG_KRETPROBES */
	240
f438d914 MH	241	extern struct kretprobe_blackpoint kretprobe_blacklist[];
f438d914 MH	242
0f95b7fc AM	243	static inline void kretprobe_assert(struct kretprobe_instance *ri,
	244	unsigned long orig_ret_address, unsigned long trampoline_address)
	245	{
	246	if (!orig_ret_address \|\| (orig_ret_address == trampoline_address)) {
	247	printk("kretprobe BUG!: Processing kretprobe %p @ %p\n",
	248	ri->rp, ri->rp->kp.addr);
	249	BUG();
	250	}
	251	}
	252
8c1c9356 AM	253	#ifdef CONFIG_KPROBES_SANITY_TEST
	254	extern int init_test_probes(void);
	255	#else
	256	static inline int init_test_probes(void)
	257	{
	258	return 0;
	259	}
	260	#endif /* CONFIG_KPROBES_SANITY_TEST */
	261
1da177e4	262	extern int arch_prepare_kprobe(struct kprobe *p);
7e1048b1 RL	263	extern void arch_arm_kprobe(struct kprobe *p);
7e1048b1 RL	264	extern void arch_disarm_kprobe(struct kprobe *p);
6772926b	265	extern int arch_init_kprobes(void);
1da177e4	266	extern void show_registers(struct pt_regs *regs);
bf8d5c52	267	extern void kprobes_inc_nmissed_count(struct kprobe *p);
be8f2743	268	extern bool arch_within_kprobe_blacklist(unsigned long addr);
1da177e4	269
e5779e8e AL	270	extern bool within_kprobe_blacklist(unsigned long addr);
e5779e8e AL	271
c802d64a HC	272	struct kprobe_insn_cache {
c802d64a HC	273	struct mutex mutex;
af96397d HC	274	void (alloc)(void); /* allocate insn page */
af96397d HC	275	void (free)(void ); /* free insn page */
c802d64a HC	276	struct list_head pages; /* list of kprobe_insn_page */
	277	size_t insn_size; /* size of instruction slot */
	278	int nr_garbage;
	279	};
	280
	281	extern kprobe_opcode_t __get_insn_slot(struct kprobe_insn_cache c);
	282	extern void __free_insn_slot(struct kprobe_insn_cache *c,
	283	kprobe_opcode_t *slot, int dirty);
	284
	285	#define DEFINE_INSN_CACHE_OPS(__name) \
	286	extern struct kprobe_insn_cache kprobe_##__name##_slots; \
	287	\
	288	static inline kprobe_opcode_t *get_##__name##_slot(void) \
	289	{ \
	290	return __get_insn_slot(&kprobe_##__name##_slots); \
	291	} \
	292	\
	293	static inline void free_##__name##_slot(kprobe_opcode_t *slot, int dirty)\
	294	{ \
	295	__free_insn_slot(&kprobe_##__name##_slots, slot, dirty); \
	296	} \
	297
	298	DEFINE_INSN_CACHE_OPS(insn);
	299
afd66255 MH	300	#ifdef CONFIG_OPTPROBES
	301	/*
	302	* Internal structure for direct jump optimized probe
	303	*/
	304	struct optimized_kprobe {
	305	struct kprobe kp;
	306	struct list_head list; /* list for optimizing queue */
	307	struct arch_optimized_insn optinsn;
	308	};
	309
	310	/* Architecture dependent functions for direct jump optimization */
	311	extern int arch_prepared_optinsn(struct arch_optimized_insn *optinsn);
	312	extern int arch_check_optimized_kprobe(struct optimized_kprobe *op);
cbf6ab52 MH	313	extern int arch_prepare_optimized_kprobe(struct optimized_kprobe *op,
cbf6ab52 MH	314	struct kprobe *orig);
afd66255	315	extern void arch_remove_optimized_kprobe(struct optimized_kprobe *op);
cd7ebe22	316	extern void arch_optimize_kprobes(struct list_head *oplist);
f984ba4e MH	317	extern void arch_unoptimize_kprobes(struct list_head *oplist,
f984ba4e MH	318	struct list_head *done_list);
afd66255	319	extern void arch_unoptimize_kprobe(struct optimized_kprobe *op);
afd66255 MH	320	extern int arch_within_optimized_kprobe(struct optimized_kprobe *op,
	321	unsigned long addr);
	322
	323	extern void opt_pre_handler(struct kprobe p, struct pt_regs regs);
b2be84df	324
c802d64a HC	325	DEFINE_INSN_CACHE_OPS(optinsn);
c802d64a HC	326
b2be84df MH	327	#ifdef CONFIG_SYSCTL
	328	extern int sysctl_kprobes_optimization;
	329	extern int proc_kprobes_optimization_handler(struct ctl_table *table,
	330	int write, void __user *buffer,
	331	size_t length, loff_t ppos);
	332	#endif
	333
afd66255	334	#endif /* CONFIG_OPTPROBES */
e7dbfe34	335	#ifdef CONFIG_KPROBES_ON_FTRACE
ae6aa16f	336	extern void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
e5253896	337	struct ftrace_ops ops, struct pt_regs regs);
ae6aa16f MH	338	extern int arch_prepare_kprobe_ftrace(struct kprobe *p);
	339	#endif
	340
f7f242ff	341	int arch_check_ftrace_location(struct kprobe *p);
afd66255	342
d217d545	343	/* Get the kprobe at this addr (if any) - called with preemption disabled */
1da177e4	344	struct kprobe get_kprobe(void addr);
ef53d9c5 S	345	void kretprobe_hash_lock(struct task_struct *tsk,
	346	struct hlist_head *head, unsigned long flags);
	347	void kretprobe_hash_unlock(struct task_struct tsk, unsigned long flags);
b94cce92	348	struct hlist_head * kretprobe_inst_table_head(struct task_struct *tsk);
1da177e4	349
e6584523 AM	350	/* kprobe_running() will just return the current_kprobe on this CPU */
	351	static inline struct kprobe *kprobe_running(void)
	352	{
b76834bc	353	return (__this_cpu_read(current_kprobe));
e6584523 AM	354	}
	355
	356	static inline void reset_current_kprobe(void)
	357	{
b76834bc	358	__this_cpu_write(current_kprobe, NULL);
e6584523 AM	359	}
	360
	361	static inline struct kprobe_ctlblk *get_kprobe_ctlblk(void)
	362	{
bdffd893	363	return this_cpu_ptr(&kprobe_ctlblk);
e6584523 AM	364	}
e6584523 AM	365
1da177e4 LT	366	int register_kprobe(struct kprobe *p);
1da177e4 LT	367	void unregister_kprobe(struct kprobe *p);
9861668f MH	368	int register_kprobes(struct kprobe **kps, int num);
9861668f MH	369	void unregister_kprobes(struct kprobe **kps, int num);
1da177e4 LT	370	int setjmp_pre_handler(struct kprobe , struct pt_regs );
	371	int longjmp_break_handler(struct kprobe , struct pt_regs );
	372	int register_jprobe(struct jprobe *p);
	373	void unregister_jprobe(struct jprobe *p);
26b31c19 MH	374	int register_jprobes(struct jprobe **jps, int num);
26b31c19 MH	375	void unregister_jprobes(struct jprobe **jps, int num);
1da177e4	376	void jprobe_return(void);
3d7e3382	377	unsigned long arch_deref_entry_point(void *);
1da177e4	378
b94cce92 HN	379	int register_kretprobe(struct kretprobe *rp);
b94cce92 HN	380	void unregister_kretprobe(struct kretprobe *rp);
4a296e07 MH	381	int register_kretprobes(struct kretprobe **rps, int num);
4a296e07 MH	382	void unregister_kretprobes(struct kretprobe **rps, int num);
b94cce92	383
b94cce92	384	void kprobe_flush_task(struct task_struct *tk);
99219a3f	385	void recycle_rp_inst(struct kretprobe_instance ri, struct hlist_head head);
8c1c9356	386
de5bd88d MH	387	int disable_kprobe(struct kprobe *kp);
	388	int enable_kprobe(struct kprobe *kp);
	389
24851d24 FW	390	void dump_kprobe(struct kprobe *kp);
24851d24 FW	391
b1801812	392	#else /* !CONFIG_KPROBES: */
00d7c05a	393
b1801812 IM	394	static inline int kprobes_built_in(void)
	395	{
	396	return 0;
	397	}
	398	static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
	399	{
	400	return 0;
	401	}
785656a4 AS	402	static inline struct kprobe get_kprobe(void addr)
	403	{
	404	return NULL;
	405	}
e6584523	406	static inline struct kprobe *kprobe_running(void)
1da177e4	407	{
e6584523	408	return NULL;
1da177e4 LT	409	}
	410	static inline int register_kprobe(struct kprobe *p)
	411	{
	412	return -ENOSYS;
	413	}
9861668f MH	414	static inline int register_kprobes(struct kprobe **kps, int num)
	415	{
	416	return -ENOSYS;
	417	}
1da177e4 LT	418	static inline void unregister_kprobe(struct kprobe *p)
	419	{
	420	}
9861668f MH	421	static inline void unregister_kprobes(struct kprobe **kps, int num)
	422	{
	423	}
1da177e4 LT	424	static inline int register_jprobe(struct jprobe *p)
	425	{
	426	return -ENOSYS;
	427	}
26b31c19 MH	428	static inline int register_jprobes(struct jprobe **jps, int num)
	429	{
	430	return -ENOSYS;
	431	}
1da177e4 LT	432	static inline void unregister_jprobe(struct jprobe *p)
	433	{
	434	}
26b31c19 MH	435	static inline void unregister_jprobes(struct jprobe **jps, int num)
	436	{
	437	}
1da177e4 LT	438	static inline void jprobe_return(void)
	439	{
	440	}
b94cce92 HN	441	static inline int register_kretprobe(struct kretprobe *rp)
	442	{
	443	return -ENOSYS;
	444	}
4a296e07 MH	445	static inline int register_kretprobes(struct kretprobe **rps, int num)
	446	{
	447	return -ENOSYS;
	448	}
b94cce92 HN	449	static inline void unregister_kretprobe(struct kretprobe *rp)
	450	{
	451	}
4a296e07 MH	452	static inline void unregister_kretprobes(struct kretprobe **rps, int num)
	453	{
	454	}
b94cce92 HN	455	static inline void kprobe_flush_task(struct task_struct *tk)
	456	{
	457	}
de5bd88d MH	458	static inline int disable_kprobe(struct kprobe *kp)
	459	{
	460	return -ENOSYS;
	461	}
	462	static inline int enable_kprobe(struct kprobe *kp)
	463	{
	464	return -ENOSYS;
	465	}
b1801812	466	#endif /* CONFIG_KPROBES */
8f9b1528 MH	467	static inline int disable_kretprobe(struct kretprobe *rp)
	468	{
	469	return disable_kprobe(&rp->kp);
	470	}
	471	static inline int enable_kretprobe(struct kretprobe *rp)
	472	{
	473	return enable_kprobe(&rp->kp);
	474	}
	475	static inline int disable_jprobe(struct jprobe *jp)
	476	{
	477	return disable_kprobe(&jp->kp);
	478	}
	479	static inline int enable_jprobe(struct jprobe *jp)
	480	{
	481	return enable_kprobe(&jp->kp);
	482	}
	483
376e2424 MH	484	#ifdef CONFIG_KPROBES
	485	/*
	486	* Blacklist ganerating macro. Specify functions which is not probed
	487	* by using this macro.
	488	*/
	489	#define __NOKPROBE_SYMBOL(fname) \
	490	static unsigned long __used \
	491	__attribute__((section("_kprobe_blacklist"))) \
	492	_kbl_addr_##fname = (unsigned long)fname;
	493	#define NOKPROBE_SYMBOL(fname) __NOKPROBE_SYMBOL(fname)
	494	#else
	495	#define NOKPROBE_SYMBOL(fname)
	496	#endif
	497
b1801812	498	#endif /* _LINUX_KPROBES_H */