/* 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_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);
#endif /* CONFIG_ARCH_STACKWALK */
#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);
unsigned int filter_irq_stacks(unsigned long *entries, unsigned int nr_entries);
#ifndef CONFIG_ARCH_STACKWALK
/* Internal interfaces. Do not use in generic code */
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 */
