[linux-2.6-block.git] / include / linux / stacktrace.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_STACKTRACE_H
#define __LINUX_STACKTRACE_H

#include <linux/types.h>
#include <asm/errno.h>

struct task_struct;
struct pt_regs;

#ifdef CONFIG_STACKTRACE
void stack_trace_print(const unsigned long *trace, unsigned int nr_entries,
		       int spaces);
int stack_trace_snprint(char *buf, size_t size, const unsigned long *entries,
			unsigned int nr_entries, int spaces);
unsigned int stack_trace_save(unsigned long *store, unsigned int size,
			      unsigned int skipnr);
unsigned int stack_trace_save_tsk(struct task_struct *task,
				  unsigned long *store, unsigned int size,
				  unsigned int skipnr);
unsigned int stack_trace_save_regs(struct pt_regs *regs, unsigned long *store,
				   unsigned int size, unsigned int skipnr);
unsigned int stack_trace_save_user(unsigned long *store, unsigned int size);

/* Internal interfaces. Do not use in generic code */
#ifdef CONFIG_ARCH_STACKWALK

/**
 * stack_trace_consume_fn - Callback for arch_stack_walk()
 * @cookie:	Caller supplied pointer handed back by arch_stack_walk()
 * @addr:	The stack entry address to consume
 *
 * Return:	True, if the entry was consumed or skipped
 *		False, if there is no space left to store
 */
typedef bool (*stack_trace_consume_fn)(void *cookie, unsigned long addr);
/**
 * arch_stack_walk - Architecture specific function to walk the stack
 * @consume_entry:	Callback which is invoked by the architecture code for
 *			each entry.
 * @cookie:		Caller supplied pointer which is handed back to
 *			@consume_entry
 * @task:		Pointer to a task struct, can be NULL
 * @regs:		Pointer to registers, can be NULL
 *
 * ============ ======= ============================================
 * task	        regs
 * ============ ======= ============================================
 * task		NULL	Stack trace from task (can be current)
 * current	regs	Stack trace starting on regs->stackpointer
 * ============ ======= ============================================
 */
void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie,
		     struct task_struct *task, struct pt_regs *regs);

/**
 * arch_stack_walk_reliable - Architecture specific function to walk the
 *			      stack reliably
 *
 * @consume_entry:	Callback which is invoked by the architecture code for
 *			each entry.
 * @cookie:		Caller supplied pointer which is handed back to
 *			@consume_entry
 * @task:		Pointer to a task struct, can be NULL
 *
 * This function returns an error if it detects any unreliable
 * features of the stack. Otherwise it guarantees that the stack
 * trace is reliable.
 *
 * If the task is not 'current', the caller *must* ensure the task is
 * inactive and its stack is pinned.
 */
int arch_stack_walk_reliable(stack_trace_consume_fn consume_entry, void *cookie,
			     struct task_struct *task);

void arch_stack_walk_user(stack_trace_consume_fn consume_entry, void *cookie,
			  const struct pt_regs *regs);

#else /* CONFIG_ARCH_STACKWALK */
struct stack_trace {
	unsigned int nr_entries, max_entries;
	unsigned long *entries;
	unsigned int skip;	/* input argument: How many entries to skip */
};

extern void save_stack_trace(struct stack_trace *trace);
extern void save_stack_trace_regs(struct pt_regs *regs,
				  struct stack_trace *trace);
extern void save_stack_trace_tsk(struct task_struct *tsk,
				struct stack_trace *trace);
extern int save_stack_trace_tsk_reliable(struct task_struct *tsk,
					 struct stack_trace *trace);
extern void save_stack_trace_user(struct stack_trace *trace);
#endif /* !CONFIG_ARCH_STACKWALK */
#endif /* CONFIG_STACKTRACE */

#if defined(CONFIG_STACKTRACE) && defined(CONFIG_HAVE_RELIABLE_STACKTRACE)
int stack_trace_save_tsk_reliable(struct task_struct *tsk, unsigned long *store,
				  unsigned int size);
#else
static inline int stack_trace_save_tsk_reliable(struct task_struct *tsk,
						unsigned long *store,
						unsigned int size)
{
	return -ENOSYS;
}
#endif

#endif /* __LINUX_STACKTRACE_H */
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
8637c099 IM	2	#ifndef __LINUX_STACKTRACE_H
	3	#define __LINUX_STACKTRACE_H
	4
9a92a6ce	5	#include <linux/types.h>
e9b98e16	6	#include <asm/errno.h>
9a92a6ce	7
897312bd	8	struct task_struct;
9c0729dc	9	struct pt_regs;
897312bd	10
8637c099	11	#ifdef CONFIG_STACKTRACE
a2970421	12	void stack_trace_print(const unsigned long *trace, unsigned int nr_entries,
e9b98e16	13	int spaces);
a2970421	14	int stack_trace_snprint(char buf, size_t size, const unsigned long entries,
e9b98e16 TG	15	unsigned int nr_entries, int spaces);
	16	unsigned int stack_trace_save(unsigned long *store, unsigned int size,
	17	unsigned int skipnr);
	18	unsigned int stack_trace_save_tsk(struct task_struct *task,
	19	unsigned long *store, unsigned int size,
	20	unsigned int skipnr);
	21	unsigned int stack_trace_save_regs(struct pt_regs regs, unsigned long store,
	22	unsigned int size, unsigned int skipnr);
	23	unsigned int stack_trace_save_user(unsigned long *store, unsigned int size);
	24
	25	/* Internal interfaces. Do not use in generic code */
214d8ca6 TG	26	#ifdef CONFIG_ARCH_STACKWALK
	27
	28	/**
	29	* stack_trace_consume_fn - Callback for arch_stack_walk()
	30	* @cookie: Caller supplied pointer handed back by arch_stack_walk()
	31	* @addr: The stack entry address to consume
214d8ca6 TG	32	*
	33	* Return: True, if the entry was consumed or skipped
	34	* False, if there is no space left to store
	35	*/
264c03a2	36	typedef bool (stack_trace_consume_fn)(void cookie, unsigned long addr);
214d8ca6 TG	37	/**
	38	* arch_stack_walk - Architecture specific function to walk the stack
	39	* @consume_entry: Callback which is invoked by the architecture code for
	40	* each entry.
	41	* @cookie: Caller supplied pointer which is handed back to
	42	* @consume_entry
	43	* @task: Pointer to a task struct, can be NULL
	44	* @regs: Pointer to registers, can be NULL
	45	*
	46	* ============ ======= ============================================
	47	* task regs
	48	* ============ ======= ============================================
	49	* task NULL Stack trace from task (can be current)
	50	* current regs Stack trace starting on regs->stackpointer
	51	* ============ ======= ============================================
	52	*/
	53	void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie,
	54	struct task_struct task, struct pt_regs regs);
b18adee4 MB	55
	56	/**
	57	* arch_stack_walk_reliable - Architecture specific function to walk the
	58	* stack reliably
	59	*
	60	* @consume_entry: Callback which is invoked by the architecture code for
	61	* each entry.
	62	* @cookie: Caller supplied pointer which is handed back to
	63	* @consume_entry
	64	* @task: Pointer to a task struct, can be NULL
	65	*
	66	* This function returns an error if it detects any unreliable
	67	* features of the stack. Otherwise it guarantees that the stack
	68	* trace is reliable.
	69	*
	70	* If the task is not 'current', the caller must ensure the task is
	71	* inactive and its stack is pinned.
	72	*/
214d8ca6 TG	73	int arch_stack_walk_reliable(stack_trace_consume_fn consume_entry, void *cookie,
214d8ca6 TG	74	struct task_struct *task);
b18adee4	75
214d8ca6 TG	76	void arch_stack_walk_user(stack_trace_consume_fn consume_entry, void *cookie,
	77	const struct pt_regs *regs);
	78
	79	#else /* CONFIG_ARCH_STACKWALK */
8637c099 IM	80	struct stack_trace {
	81	unsigned int nr_entries, max_entries;
	82	unsigned long *entries;
2c34f6f7	83	unsigned int skip; /* input argument: How many entries to skip */
8637c099 IM	84	};
8637c099 IM	85
ab1b6f03	86	extern void save_stack_trace(struct stack_trace *trace);
39581062 MH	87	extern void save_stack_trace_regs(struct pt_regs *regs,
39581062 MH	88	struct stack_trace *trace);
9745512c AV	89	extern void save_stack_trace_tsk(struct task_struct *tsk,
9745512c AV	90	struct stack_trace *trace);
af085d90 JP	91	extern int save_stack_trace_tsk_reliable(struct task_struct *tsk,
af085d90 JP	92	struct stack_trace *trace);
02b67518	93	extern void save_stack_trace_user(struct stack_trace *trace);
214d8ca6	94	#endif /* !CONFIG_ARCH_STACKWALK */
af085d90	95	#endif /* CONFIG_STACKTRACE */
8637c099	96
e9b98e16 TG	97	#if defined(CONFIG_STACKTRACE) && defined(CONFIG_HAVE_RELIABLE_STACKTRACE)
	98	int stack_trace_save_tsk_reliable(struct task_struct tsk, unsigned long store,
	99	unsigned int size);
	100	#else
	101	static inline int stack_trace_save_tsk_reliable(struct task_struct *tsk,
	102	unsigned long *store,
	103	unsigned int size)
	104	{
	105	return -ENOSYS;
	106	}
	107	#endif
	108
af085d90	109	#endif /* __LINUX_STACKTRACE_H */