[deliverable/linux.git] / include / linux / ptrace.h

#ifndef _LINUX_PTRACE_H
#define _LINUX_PTRACE_H
/* ptrace.h */
/* structs and defines to help the user use the ptrace system call. */

/* has the defines to get at the registers. */

#define PTRACE_TRACEME		   0
#define PTRACE_PEEKTEXT		   1
#define PTRACE_PEEKDATA		   2
#define PTRACE_PEEKUSR		   3
#define PTRACE_POKETEXT		   4
#define PTRACE_POKEDATA		   5
#define PTRACE_POKEUSR		   6
#define PTRACE_CONT		   7
#define PTRACE_KILL		   8
#define PTRACE_SINGLESTEP	   9

#define PTRACE_ATTACH		  16
#define PTRACE_DETACH		  17

#define PTRACE_SYSCALL		  24

/* 0x4200-0x4300 are reserved for architecture-independent additions.  */
#define PTRACE_SETOPTIONS	0x4200
#define PTRACE_GETEVENTMSG	0x4201
#define PTRACE_GETSIGINFO	0x4202
#define PTRACE_SETSIGINFO	0x4203

/* options set using PTRACE_SETOPTIONS */
#define PTRACE_O_TRACESYSGOOD	0x00000001
#define PTRACE_O_TRACEFORK	0x00000002
#define PTRACE_O_TRACEVFORK	0x00000004
#define PTRACE_O_TRACECLONE	0x00000008
#define PTRACE_O_TRACEEXEC	0x00000010
#define PTRACE_O_TRACEVFORKDONE	0x00000020
#define PTRACE_O_TRACEEXIT	0x00000040

#define PTRACE_O_MASK		0x0000007f

/* Wait extended result codes for the above trace options.  */
#define PTRACE_EVENT_FORK	1
#define PTRACE_EVENT_VFORK	2
#define PTRACE_EVENT_CLONE	3
#define PTRACE_EVENT_EXEC	4
#define PTRACE_EVENT_VFORK_DONE	5
#define PTRACE_EVENT_EXIT	6

#include <asm/ptrace.h>

#ifdef __KERNEL__
/*
 * Ptrace flags
 *
 * The owner ship rules for task->ptrace which holds the ptrace
 * flags is simple.  When a task is running it owns it's task->ptrace
 * flags.  When the a task is stopped the ptracer owns task->ptrace.
 */

#define PT_PTRACED	0x00000001
#define PT_DTRACE	0x00000002	/* delayed trace (used on m68k, i386) */
#define PT_TRACESYSGOOD	0x00000004
#define PT_PTRACE_CAP	0x00000008	/* ptracer can follow suid-exec */
#define PT_TRACE_FORK	0x00000010
#define PT_TRACE_VFORK	0x00000020
#define PT_TRACE_CLONE	0x00000040
#define PT_TRACE_EXEC	0x00000080
#define PT_TRACE_VFORK_DONE	0x00000100
#define PT_TRACE_EXIT	0x00000200

#define PT_TRACE_MASK	0x000003f4

/* single stepping state bits (used on ARM and PA-RISC) */
#define PT_SINGLESTEP_BIT	31
#define PT_SINGLESTEP		(1<<PT_SINGLESTEP_BIT)
#define PT_BLOCKSTEP_BIT	30
#define PT_BLOCKSTEP		(1<<PT_BLOCKSTEP_BIT)

#include <linux/compiler.h>		/* For unlikely.  */
#include <linux/sched.h>		/* For struct task_struct.  */


extern long arch_ptrace(struct task_struct *child, long request, long addr, long data);
extern struct task_struct *ptrace_get_task_struct(pid_t pid);
extern int ptrace_traceme(void);
extern int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len);
extern int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len);
extern int ptrace_attach(struct task_struct *tsk);
extern int ptrace_detach(struct task_struct *, unsigned int);
extern void ptrace_disable(struct task_struct *);
extern int ptrace_check_attach(struct task_struct *task, int kill);
extern int ptrace_request(struct task_struct *child, long request, long addr, long data);
extern void ptrace_notify(int exit_code);
extern void __ptrace_link(struct task_struct *child,
			  struct task_struct *new_parent);
extern void __ptrace_unlink(struct task_struct *child);
extern void ptrace_untrace(struct task_struct *child);
#define PTRACE_MODE_READ   1
#define PTRACE_MODE_ATTACH 2
/* Returns 0 on success, -errno on denial. */
extern int __ptrace_may_access(struct task_struct *task, unsigned int mode);
/* Returns true on success, false on denial. */
extern bool ptrace_may_access(struct task_struct *task, unsigned int mode);

static inline int ptrace_reparented(struct task_struct *child)
{
	return child->real_parent != child->parent;
}
static inline void ptrace_link(struct task_struct *child,
			       struct task_struct *new_parent)
{
	if (unlikely(child->ptrace))
		__ptrace_link(child, new_parent);
}
static inline void ptrace_unlink(struct task_struct *child)
{
	if (unlikely(child->ptrace))
		__ptrace_unlink(child);
}

int generic_ptrace_peekdata(struct task_struct *tsk, long addr, long data);
int generic_ptrace_pokedata(struct task_struct *tsk, long addr, long data);

/**
 * task_ptrace - return %PT_* flags that apply to a task
 * @task:	pointer to &task_struct in question
 *
 * Returns the %PT_* flags that apply to @task.
 */
static inline int task_ptrace(struct task_struct *task)
{
	return task->ptrace;
}

/**
 * ptrace_event - possibly stop for a ptrace event notification
 * @mask:	%PT_* bit to check in @current->ptrace
 * @event:	%PTRACE_EVENT_* value to report if @mask is set
 * @message:	value for %PTRACE_GETEVENTMSG to return
 *
 * This checks the @mask bit to see if ptrace wants stops for this event.
 * If so we stop, reporting @event and @message to the ptrace parent.
 *
 * Returns nonzero if we did a ptrace notification, zero if not.
 *
 * Called without locks.
 */
static inline int ptrace_event(int mask, int event, unsigned long message)
{
	if (mask && likely(!(current->ptrace & mask)))
		return 0;
	current->ptrace_message = message;
	ptrace_notify((event << 8) | SIGTRAP);
	return 1;
}

#ifndef force_successful_syscall_return
/*
 * System call handlers that, upon successful completion, need to return a
 * negative value should call force_successful_syscall_return() right before
 * returning.  On architectures where the syscall convention provides for a
 * separate error flag (e.g., alpha, ia64, ppc{,64}, sparc{,64}, possibly
 * others), this macro can be used to ensure that the error flag will not get
 * set.  On architectures which do not support a separate error flag, the macro
 * is a no-op and the spurious error condition needs to be filtered out by some
 * other means (e.g., in user-level, by passing an extra argument to the
 * syscall handler, or something along those lines).
 */
#define force_successful_syscall_return() do { } while (0)
#endif

/*
 * <asm/ptrace.h> should define the following things inside #ifdef __KERNEL__.
 *
 * These do-nothing inlines are used when the arch does not
 * implement single-step.  The kerneldoc comments are here
 * to document the interface for all arch definitions.
 */

#ifndef arch_has_single_step
/**
 * arch_has_single_step - does this CPU support user-mode single-step?
 *
 * If this is defined, then there must be function declarations or
 * inlines for user_enable_single_step() and user_disable_single_step().
 * arch_has_single_step() should evaluate to nonzero iff the machine
 * supports instruction single-step for user mode.
 * It can be a constant or it can test a CPU feature bit.
 */
#define arch_has_single_step()		(0)

/**
 * user_enable_single_step - single-step in user-mode task
 * @task: either current or a task stopped in %TASK_TRACED
 *
 * This can only be called when arch_has_single_step() has returned nonzero.
 * Set @task so that when it returns to user mode, it will trap after the
 * next single instruction executes.  If arch_has_block_step() is defined,
 * this must clear the effects of user_enable_block_step() too.
 */
static inline void user_enable_single_step(struct task_struct *task)
{
	BUG();			/* This can never be called.  */
}

/**
 * user_disable_single_step - cancel user-mode single-step
 * @task: either current or a task stopped in %TASK_TRACED
 *
 * Clear @task of the effects of user_enable_single_step() and
 * user_enable_block_step().  This can be called whether or not either
 * of those was ever called on @task, and even if arch_has_single_step()
 * returned zero.
 */
static inline void user_disable_single_step(struct task_struct *task)
{
}
#endif	/* arch_has_single_step */

#ifndef arch_has_block_step
/**
 * arch_has_block_step - does this CPU support user-mode block-step?
 *
 * If this is defined, then there must be a function declaration or inline
 * for user_enable_block_step(), and arch_has_single_step() must be defined
 * too.  arch_has_block_step() should evaluate to nonzero iff the machine
 * supports step-until-branch for user mode.  It can be a constant or it
 * can test a CPU feature bit.
 */
#define arch_has_block_step()		(0)

/**
 * user_enable_block_step - step until branch in user-mode task
 * @task: either current or a task stopped in %TASK_TRACED
 *
 * This can only be called when arch_has_block_step() has returned nonzero,
 * and will never be called when single-instruction stepping is being used.
 * Set @task so that when it returns to user mode, it will trap after the
 * next branch or trap taken.
 */
static inline void user_enable_block_step(struct task_struct *task)
{
	BUG();			/* This can never be called.  */
}
#endif	/* arch_has_block_step */

#ifndef arch_ptrace_stop_needed
/**
 * arch_ptrace_stop_needed - Decide whether arch_ptrace_stop() should be called
 * @code:	current->exit_code value ptrace will stop with
 * @info:	siginfo_t pointer (or %NULL) for signal ptrace will stop with
 *
 * This is called with the siglock held, to decide whether or not it's
 * necessary to release the siglock and call arch_ptrace_stop() with the
 * same @code and @info arguments.  It can be defined to a constant if
 * arch_ptrace_stop() is never required, or always is.  On machines where
 * this makes sense, it should be defined to a quick test to optimize out
 * calling arch_ptrace_stop() when it would be superfluous.  For example,
 * if the thread has not been back to user mode since the last stop, the
 * thread state might indicate that nothing needs to be done.
 */
#define arch_ptrace_stop_needed(code, info)	(0)
#endif

#ifndef arch_ptrace_stop
/**
 * arch_ptrace_stop - Do machine-specific work before stopping for ptrace
 * @code:	current->exit_code value ptrace will stop with
 * @info:	siginfo_t pointer (or %NULL) for signal ptrace will stop with
 *
 * This is called with no locks held when arch_ptrace_stop_needed() has
 * just returned nonzero.  It is allowed to block, e.g. for user memory
 * access.  The arch can have machine-specific work to be done before
 * ptrace stops.  On ia64, register backing store gets written back to user
 * memory here.  Since this can be costly (requires dropping the siglock),
 * we only do it when the arch requires it for this particular stop, as
 * indicated by arch_ptrace_stop_needed().
 */
#define arch_ptrace_stop(code, info)		do { } while (0)
#endif

#endif

#endif
Commit	Line	Data
1da177e4 LT	1	#ifndef _LINUX_PTRACE_H
	2	#define _LINUX_PTRACE_H
	3	/* ptrace.h */
	4	/* structs and defines to help the user use the ptrace system call. */
	5
	6	/* has the defines to get at the registers. */
	7
	8	#define PTRACE_TRACEME 0
	9	#define PTRACE_PEEKTEXT 1
	10	#define PTRACE_PEEKDATA 2
	11	#define PTRACE_PEEKUSR 3
	12	#define PTRACE_POKETEXT 4
	13	#define PTRACE_POKEDATA 5
	14	#define PTRACE_POKEUSR 6
	15	#define PTRACE_CONT 7
	16	#define PTRACE_KILL 8
	17	#define PTRACE_SINGLESTEP 9
	18
416bc512 RM	19	#define PTRACE_ATTACH 16
416bc512 RM	20	#define PTRACE_DETACH 17
1da177e4 LT	21
	22	#define PTRACE_SYSCALL 24
	23
	24	/* 0x4200-0x4300 are reserved for architecture-independent additions. */
	25	#define PTRACE_SETOPTIONS 0x4200
	26	#define PTRACE_GETEVENTMSG 0x4201
	27	#define PTRACE_GETSIGINFO 0x4202
	28	#define PTRACE_SETSIGINFO 0x4203
	29
	30	/* options set using PTRACE_SETOPTIONS */
	31	#define PTRACE_O_TRACESYSGOOD 0x00000001
	32	#define PTRACE_O_TRACEFORK 0x00000002
	33	#define PTRACE_O_TRACEVFORK 0x00000004
	34	#define PTRACE_O_TRACECLONE 0x00000008
	35	#define PTRACE_O_TRACEEXEC 0x00000010
	36	#define PTRACE_O_TRACEVFORKDONE 0x00000020
	37	#define PTRACE_O_TRACEEXIT 0x00000040
	38
	39	#define PTRACE_O_MASK 0x0000007f
	40
	41	/* Wait extended result codes for the above trace options. */
	42	#define PTRACE_EVENT_FORK 1
	43	#define PTRACE_EVENT_VFORK 2
	44	#define PTRACE_EVENT_CLONE 3
	45	#define PTRACE_EVENT_EXEC 4
	46	#define PTRACE_EVENT_VFORK_DONE 5
	47	#define PTRACE_EVENT_EXIT 6
	48
	49	#include <asm/ptrace.h>
	50
	51	#ifdef __KERNEL__
	52	/*
	53	* Ptrace flags
260ea101 EB	54	*
	55	* The owner ship rules for task->ptrace which holds the ptrace
	56	* flags is simple. When a task is running it owns it's task->ptrace
	57	* flags. When the a task is stopped the ptracer owns task->ptrace.
1da177e4 LT	58	*/
	59
	60	#define PT_PTRACED 0x00000001
	61	#define PT_DTRACE 0x00000002 /* delayed trace (used on m68k, i386) */
	62	#define PT_TRACESYSGOOD 0x00000004
	63	#define PT_PTRACE_CAP 0x00000008 /* ptracer can follow suid-exec */
	64	#define PT_TRACE_FORK 0x00000010
	65	#define PT_TRACE_VFORK 0x00000020
	66	#define PT_TRACE_CLONE 0x00000040
	67	#define PT_TRACE_EXEC 0x00000080
	68	#define PT_TRACE_VFORK_DONE 0x00000100
	69	#define PT_TRACE_EXIT 0x00000200
1da177e4 LT	70
	71	#define PT_TRACE_MASK 0x000003f4
	72
	73	/* single stepping state bits (used on ARM and PA-RISC) */
	74	#define PT_SINGLESTEP_BIT 31
	75	#define PT_SINGLESTEP (1<<PT_SINGLESTEP_BIT)
	76	#define PT_BLOCKSTEP_BIT 30
	77	#define PT_BLOCKSTEP (1<<PT_BLOCKSTEP_BIT)
	78
	79	#include <linux/compiler.h> /* For unlikely. */
	80	#include <linux/sched.h> /* For struct task_struct. */
	81
481bed45 CH	82
481bed45 CH	83	extern long arch_ptrace(struct task_struct *child, long request, long addr, long data);
6b9c7ed8 CH	84	extern struct task_struct *ptrace_get_task_struct(pid_t pid);
6b9c7ed8 CH	85	extern int ptrace_traceme(void);
1da177e4 LT	86	extern int ptrace_readdata(struct task_struct tsk, unsigned long src, char __user dst, int len);
	87	extern int ptrace_writedata(struct task_struct tsk, char __user src, unsigned long dst, int len);
	88	extern int ptrace_attach(struct task_struct *tsk);
	89	extern int ptrace_detach(struct task_struct *, unsigned int);
	90	extern void ptrace_disable(struct task_struct *);
	91	extern int ptrace_check_attach(struct task_struct *task, int kill);
	92	extern int ptrace_request(struct task_struct *child, long request, long addr, long data);
	93	extern void ptrace_notify(int exit_code);
	94	extern void __ptrace_link(struct task_struct *child,
	95	struct task_struct *new_parent);
	96	extern void __ptrace_unlink(struct task_struct *child);
	97	extern void ptrace_untrace(struct task_struct *child);
006ebb40 SS	98	#define PTRACE_MODE_READ 1
	99	#define PTRACE_MODE_ATTACH 2
	100	/* Returns 0 on success, -errno on denial. */
	101	extern int __ptrace_may_access(struct task_struct *task, unsigned int mode);
	102	/* Returns true on success, false on denial. */
	103	extern bool ptrace_may_access(struct task_struct *task, unsigned int mode);
1da177e4	104
53b6f9fb ON	105	static inline int ptrace_reparented(struct task_struct *child)
	106	{
	107	return child->real_parent != child->parent;
	108	}
1da177e4 LT	109	static inline void ptrace_link(struct task_struct *child,
	110	struct task_struct *new_parent)
	111	{
	112	if (unlikely(child->ptrace))
	113	__ptrace_link(child, new_parent);
	114	}
	115	static inline void ptrace_unlink(struct task_struct *child)
	116	{
	117	if (unlikely(child->ptrace))
	118	__ptrace_unlink(child);
	119	}
	120
76647323	121	int generic_ptrace_peekdata(struct task_struct *tsk, long addr, long data);
f284ce72	122	int generic_ptrace_pokedata(struct task_struct *tsk, long addr, long data);
1da177e4	123
88ac2921 RM	124	/**
	125	* task_ptrace - return %PT_* flags that apply to a task
	126	* @task: pointer to &task_struct in question
	127	*
	128	* Returns the %PT_* flags that apply to @task.
	129	*/
	130	static inline int task_ptrace(struct task_struct *task)
	131	{
	132	return task->ptrace;
	133	}
	134
	135	/**
	136	* ptrace_event - possibly stop for a ptrace event notification
	137	* @mask: %PT_* bit to check in @current->ptrace
	138	* @event: %PTRACE_EVENT_* value to report if @mask is set
	139	* @message: value for %PTRACE_GETEVENTMSG to return
	140	*
	141	* This checks the @mask bit to see if ptrace wants stops for this event.
	142	* If so we stop, reporting @event and @message to the ptrace parent.
	143	*
	144	* Returns nonzero if we did a ptrace notification, zero if not.
	145	*
	146	* Called without locks.
	147	*/
	148	static inline int ptrace_event(int mask, int event, unsigned long message)
	149	{
	150	if (mask && likely(!(current->ptrace & mask)))
	151	return 0;
	152	current->ptrace_message = message;
	153	ptrace_notify((event << 8) \| SIGTRAP);
	154	return 1;
	155	}
	156
1da177e4 LT	157	#ifndef force_successful_syscall_return
	158	/*
	159	* System call handlers that, upon successful completion, need to return a
	160	* negative value should call force_successful_syscall_return() right before
	161	* returning. On architectures where the syscall convention provides for a
	162	* separate error flag (e.g., alpha, ia64, ppc{,64}, sparc{,64}, possibly
	163	* others), this macro can be used to ensure that the error flag will not get
	164	* set. On architectures which do not support a separate error flag, the macro
	165	* is a no-op and the spurious error condition needs to be filtered out by some
	166	* other means (e.g., in user-level, by passing an extra argument to the
	167	* syscall handler, or something along those lines).
	168	*/
	169	#define force_successful_syscall_return() do { } while (0)
	170	#endif
	171
fb7fa8f1 RM	172	/*
	173	* <asm/ptrace.h> should define the following things inside #ifdef __KERNEL__.
	174	*
	175	* These do-nothing inlines are used when the arch does not
	176	* implement single-step. The kerneldoc comments are here
	177	* to document the interface for all arch definitions.
	178	*/
	179
	180	#ifndef arch_has_single_step
	181	/**
	182	* arch_has_single_step - does this CPU support user-mode single-step?
	183	*
	184	* If this is defined, then there must be function declarations or
	185	* inlines for user_enable_single_step() and user_disable_single_step().
	186	* arch_has_single_step() should evaluate to nonzero iff the machine
	187	* supports instruction single-step for user mode.
	188	* It can be a constant or it can test a CPU feature bit.
	189	*/
	190	#define arch_has_single_step() (0)
	191
	192	/**
	193	* user_enable_single_step - single-step in user-mode task
	194	* @task: either current or a task stopped in %TASK_TRACED
	195	*
	196	* This can only be called when arch_has_single_step() has returned nonzero.
	197	* Set @task so that when it returns to user mode, it will trap after the
dc802c2d RM	198	* next single instruction executes. If arch_has_block_step() is defined,
dc802c2d RM	199	* this must clear the effects of user_enable_block_step() too.
fb7fa8f1 RM	200	*/
	201	static inline void user_enable_single_step(struct task_struct *task)
	202	{
	203	BUG(); /* This can never be called. */
	204	}
	205
	206	/**
	207	* user_disable_single_step - cancel user-mode single-step
	208	* @task: either current or a task stopped in %TASK_TRACED
	209	*
dc802c2d RM	210	* Clear @task of the effects of user_enable_single_step() and
	211	* user_enable_block_step(). This can be called whether or not either
	212	* of those was ever called on @task, and even if arch_has_single_step()
	213	* returned zero.
fb7fa8f1 RM	214	*/
	215	static inline void user_disable_single_step(struct task_struct *task)
	216	{
	217	}
	218	#endif /* arch_has_single_step */
	219
dc802c2d RM	220	#ifndef arch_has_block_step
	221	/**
	222	* arch_has_block_step - does this CPU support user-mode block-step?
	223	*
	224	* If this is defined, then there must be a function declaration or inline
	225	* for user_enable_block_step(), and arch_has_single_step() must be defined
	226	* too. arch_has_block_step() should evaluate to nonzero iff the machine
	227	* supports step-until-branch for user mode. It can be a constant or it
	228	* can test a CPU feature bit.
	229	*/
5b88abbf	230	#define arch_has_block_step() (0)
dc802c2d RM	231
	232	/**
	233	* user_enable_block_step - step until branch in user-mode task
	234	* @task: either current or a task stopped in %TASK_TRACED
	235	*
	236	* This can only be called when arch_has_block_step() has returned nonzero,
	237	* and will never be called when single-instruction stepping is being used.
	238	* Set @task so that when it returns to user mode, it will trap after the
	239	* next branch or trap taken.
	240	*/
	241	static inline void user_enable_block_step(struct task_struct *task)
	242	{
	243	BUG(); /* This can never be called. */
	244	}
	245	#endif /* arch_has_block_step */
	246
1a669c2f RM	247	#ifndef arch_ptrace_stop_needed
	248	/**
	249	* arch_ptrace_stop_needed - Decide whether arch_ptrace_stop() should be called
	250	* @code: current->exit_code value ptrace will stop with
	251	* @info: siginfo_t pointer (or %NULL) for signal ptrace will stop with
	252	*
	253	* This is called with the siglock held, to decide whether or not it's
	254	* necessary to release the siglock and call arch_ptrace_stop() with the
	255	* same @code and @info arguments. It can be defined to a constant if
	256	* arch_ptrace_stop() is never required, or always is. On machines where
	257	* this makes sense, it should be defined to a quick test to optimize out
	258	* calling arch_ptrace_stop() when it would be superfluous. For example,
	259	* if the thread has not been back to user mode since the last stop, the
	260	* thread state might indicate that nothing needs to be done.
	261	*/
	262	#define arch_ptrace_stop_needed(code, info) (0)
	263	#endif
	264
	265	#ifndef arch_ptrace_stop
	266	/**
	267	* arch_ptrace_stop - Do machine-specific work before stopping for ptrace
	268	* @code: current->exit_code value ptrace will stop with
	269	* @info: siginfo_t pointer (or %NULL) for signal ptrace will stop with
	270	*
	271	* This is called with no locks held when arch_ptrace_stop_needed() has
	272	* just returned nonzero. It is allowed to block, e.g. for user memory
	273	* access. The arch can have machine-specific work to be done before
	274	* ptrace stops. On ia64, register backing store gets written back to user
	275	* memory here. Since this can be costly (requires dropping the siglock),
	276	* we only do it when the arch requires it for this particular stop, as
	277	* indicated by arch_ptrace_stop_needed().
	278	*/
	279	#define arch_ptrace_stop(code, info) do { } while (0)
	280	#endif
	281
1da177e4 LT	282	#endif
	283
	284	#endif