99 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			99 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
 | |
| /*
 | |
|  * Most of this ideas comes from x86.
 | |
|  *
 | |
|  * Copyright (C) 2022 Loongson Technology Corporation Limited
 | |
|  */
 | |
| #ifndef _ASM_UNWIND_H
 | |
| #define _ASM_UNWIND_H
 | |
| 
 | |
| #include <linux/sched.h>
 | |
| #include <linux/ftrace.h>
 | |
| 
 | |
| #include <asm/ptrace.h>
 | |
| #include <asm/stacktrace.h>
 | |
| 
 | |
| enum unwinder_type {
 | |
| 	UNWINDER_GUESS,
 | |
| 	UNWINDER_PROLOGUE,
 | |
| 	UNWINDER_ORC,
 | |
| };
 | |
| 
 | |
| struct unwind_state {
 | |
| 	char type; /* UNWINDER_XXX */
 | |
| 	struct stack_info stack_info;
 | |
| 	struct task_struct *task;
 | |
| 	bool first, error, reset;
 | |
| 	int graph_idx;
 | |
| 	unsigned long sp, fp, pc, ra;
 | |
| };
 | |
| 
 | |
| bool default_next_frame(struct unwind_state *state);
 | |
| 
 | |
| void unwind_start(struct unwind_state *state,
 | |
| 		  struct task_struct *task, struct pt_regs *regs);
 | |
| bool unwind_next_frame(struct unwind_state *state);
 | |
| unsigned long unwind_get_return_address(struct unwind_state *state);
 | |
| 
 | |
| static inline bool unwind_done(struct unwind_state *state)
 | |
| {
 | |
| 	return state->stack_info.type == STACK_TYPE_UNKNOWN;
 | |
| }
 | |
| 
 | |
| static inline bool unwind_error(struct unwind_state *state)
 | |
| {
 | |
| 	return state->error;
 | |
| }
 | |
| 
 | |
| #define GRAPH_FAKE_OFFSET (sizeof(struct pt_regs) - offsetof(struct pt_regs, regs[1]))
 | |
| 
 | |
| static inline unsigned long unwind_graph_addr(struct unwind_state *state,
 | |
| 					unsigned long pc, unsigned long cfa)
 | |
| {
 | |
| 	return ftrace_graph_ret_addr(state->task, &state->graph_idx,
 | |
| 				     pc, (unsigned long *)(cfa - GRAPH_FAKE_OFFSET));
 | |
| }
 | |
| 
 | |
| static __always_inline void __unwind_start(struct unwind_state *state,
 | |
| 					struct task_struct *task, struct pt_regs *regs)
 | |
| {
 | |
| 	memset(state, 0, sizeof(*state));
 | |
| 	if (regs) {
 | |
| 		state->sp = regs->regs[3];
 | |
| 		state->pc = regs->csr_era;
 | |
| 		state->ra = regs->regs[1];
 | |
| 		state->fp = regs->regs[22];
 | |
| 	} else if (task && task != current) {
 | |
| 		state->sp = thread_saved_fp(task);
 | |
| 		state->pc = thread_saved_ra(task);
 | |
| 		state->ra = 0;
 | |
| 		state->fp = 0;
 | |
| 	} else {
 | |
| 		state->sp = (unsigned long)__builtin_frame_address(0);
 | |
| 		state->pc = (unsigned long)__builtin_return_address(0);
 | |
| 		state->ra = 0;
 | |
| 		state->fp = 0;
 | |
| 	}
 | |
| 	state->task = task;
 | |
| 	get_stack_info(state->sp, state->task, &state->stack_info);
 | |
| 	state->pc = unwind_graph_addr(state, state->pc, state->sp);
 | |
| }
 | |
| 
 | |
| static __always_inline unsigned long __unwind_get_return_address(struct unwind_state *state)
 | |
| {
 | |
| 	if (unwind_done(state))
 | |
| 		return 0;
 | |
| 
 | |
| 	return __kernel_text_address(state->pc) ? state->pc : 0;
 | |
| }
 | |
| 
 | |
| #ifdef CONFIG_UNWINDER_ORC
 | |
| void unwind_init(void);
 | |
| void unwind_module_init(struct module *mod, void *orc_ip, size_t orc_ip_size, void *orc, size_t orc_size);
 | |
| #else
 | |
| static inline void unwind_init(void) {}
 | |
| static inline void unwind_module_init(struct module *mod, void *orc_ip, size_t orc_ip_size, void *orc, size_t orc_size) {}
 | |
| #endif
 | |
| 
 | |
| #endif /* _ASM_UNWIND_H */
 |