1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __LINUX_STACKTRACE_H 3 #define __LINUX_STACKTRACE_H 4 5 #include <linux/types.h> 6 #include <asm/errno.h> 7 8 struct task_struct; 9 struct pt_regs; 10 11 #ifdef CONFIG_STACKTRACE 12 void stack_trace_print(const unsigned long *trace, unsigned int nr_entries, 13 int spaces); 14 int stack_trace_snprint(char *buf, size_t size, const unsigned long *entries, 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 */ 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 32 * 33 * Return: True, if the entry was consumed or skipped 34 * False, if there is no space left to store 35 */ 36 typedef bool (*stack_trace_consume_fn)(void *cookie, unsigned long addr); 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); 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 */ 73 int arch_stack_walk_reliable(stack_trace_consume_fn consume_entry, void *cookie, 74 struct task_struct *task); 75 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 */ 80 struct stack_trace { 81 unsigned int nr_entries, max_entries; 82 unsigned long *entries; 83 unsigned int skip; /* input argument: How many entries to skip */ 84 }; 85 86 extern void save_stack_trace(struct stack_trace *trace); 87 extern void save_stack_trace_regs(struct pt_regs *regs, 88 struct stack_trace *trace); 89 extern void save_stack_trace_tsk(struct task_struct *tsk, 90 struct stack_trace *trace); 91 extern int save_stack_trace_tsk_reliable(struct task_struct *tsk, 92 struct stack_trace *trace); 93 extern void save_stack_trace_user(struct stack_trace *trace); 94 #endif /* !CONFIG_ARCH_STACKWALK */ 95 #endif /* CONFIG_STACKTRACE */ 96 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 108 109 #endif /* __LINUX_STACKTRACE_H */ 110