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_ARCH_STACKWALK 12 13 /** 14 * stack_trace_consume_fn - Callback for arch_stack_walk() 15 * @cookie: Caller supplied pointer handed back by arch_stack_walk() 16 * @addr: The stack entry address to consume 17 * 18 * Return: True, if the entry was consumed or skipped 19 * False, if there is no space left to store 20 */ 21 typedef bool (*stack_trace_consume_fn)(void *cookie, unsigned long addr); 22 /** 23 * arch_stack_walk - Architecture specific function to walk the stack 24 * @consume_entry: Callback which is invoked by the architecture code for 25 * each entry. 26 * @cookie: Caller supplied pointer which is handed back to 27 * @consume_entry 28 * @task: Pointer to a task struct, can be NULL 29 * @regs: Pointer to registers, can be NULL 30 * 31 * ============ ======= ============================================ 32 * task regs 33 * ============ ======= ============================================ 34 * task NULL Stack trace from task (can be current) 35 * current regs Stack trace starting on regs->stackpointer 36 * ============ ======= ============================================ 37 */ 38 void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie, 39 struct task_struct *task, struct pt_regs *regs); 40 41 /** 42 * arch_stack_walk_reliable - Architecture specific function to walk the 43 * stack reliably 44 * 45 * @consume_entry: Callback which is invoked by the architecture code for 46 * each entry. 47 * @cookie: Caller supplied pointer which is handed back to 48 * @consume_entry 49 * @task: Pointer to a task struct, can be NULL 50 * 51 * This function returns an error if it detects any unreliable 52 * features of the stack. Otherwise it guarantees that the stack 53 * trace is reliable. 54 * 55 * If the task is not 'current', the caller *must* ensure the task is 56 * inactive and its stack is pinned. 57 */ 58 int arch_stack_walk_reliable(stack_trace_consume_fn consume_entry, void *cookie, 59 struct task_struct *task); 60 61 void arch_stack_walk_user(stack_trace_consume_fn consume_entry, void *cookie, 62 const struct pt_regs *regs); 63 #endif /* CONFIG_ARCH_STACKWALK */ 64 65 #ifdef CONFIG_STACKTRACE 66 void stack_trace_print(const unsigned long *trace, unsigned int nr_entries, 67 int spaces); 68 int stack_trace_snprint(char *buf, size_t size, const unsigned long *entries, 69 unsigned int nr_entries, int spaces); 70 unsigned int stack_trace_save(unsigned long *store, unsigned int size, 71 unsigned int skipnr); 72 unsigned int stack_trace_save_tsk(struct task_struct *task, 73 unsigned long *store, unsigned int size, 74 unsigned int skipnr); 75 unsigned int stack_trace_save_regs(struct pt_regs *regs, unsigned long *store, 76 unsigned int size, unsigned int skipnr); 77 unsigned int stack_trace_save_user(unsigned long *store, unsigned int size); 78 unsigned int filter_irq_stacks(unsigned long *entries, unsigned int nr_entries); 79 80 #ifndef CONFIG_ARCH_STACKWALK 81 /* Internal interfaces. Do not use in generic code */ 82 struct stack_trace { 83 unsigned int nr_entries, max_entries; 84 unsigned long *entries; 85 unsigned int skip; /* input argument: How many entries to skip */ 86 }; 87 88 extern void save_stack_trace(struct stack_trace *trace); 89 extern void save_stack_trace_regs(struct pt_regs *regs, 90 struct stack_trace *trace); 91 extern void save_stack_trace_tsk(struct task_struct *tsk, 92 struct stack_trace *trace); 93 extern int save_stack_trace_tsk_reliable(struct task_struct *tsk, 94 struct stack_trace *trace); 95 extern void save_stack_trace_user(struct stack_trace *trace); 96 #endif /* !CONFIG_ARCH_STACKWALK */ 97 #endif /* CONFIG_STACKTRACE */ 98 99 #if defined(CONFIG_STACKTRACE) && defined(CONFIG_HAVE_RELIABLE_STACKTRACE) 100 int stack_trace_save_tsk_reliable(struct task_struct *tsk, unsigned long *store, 101 unsigned int size); 102 #else 103 static inline int stack_trace_save_tsk_reliable(struct task_struct *tsk, 104 unsigned long *store, 105 unsigned int size) 106 { 107 return -ENOSYS; 108 } 109 #endif 110 111 #endif /* __LINUX_STACKTRACE_H */ 112