1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _UNWIND_H_
3 #define _UNWIND_H_
4 
5 #include <linux/list.h>
6 
7 /* Max number of levels to backtrace */
8 #define MAX_UNWIND_ENTRIES	30
9 
10 /* From ABI specifications */
11 struct unwind_table_entry {
12 	unsigned int region_start;
13 	unsigned int region_end;
14 	unsigned int Cannot_unwind:1; /* 0 */
15 	unsigned int Millicode:1;	/* 1 */
16 	unsigned int Millicode_save_sr0:1;	/* 2 */
17 	unsigned int Region_description:2;	/* 3..4 */
18 	unsigned int reserved1:1;	/* 5 */
19 	unsigned int Entry_SR:1;	/* 6 */
20 	unsigned int Entry_FR:4;	/* number saved *//* 7..10 */
21 	unsigned int Entry_GR:5;	/* number saved *//* 11..15 */
22 	unsigned int Args_stored:1;	/* 16 */
23 	unsigned int Variable_Frame:1;	/* 17 */
24 	unsigned int Separate_Package_Body:1;	/* 18 */
25 	unsigned int Frame_Extension_Millicode:1;	/* 19 */
26 	unsigned int Stack_Overflow_Check:1;	/* 20 */
27 	unsigned int Two_Instruction_SP_Increment:1;	/* 21 */
28 	unsigned int Ada_Region:1;	/* 22 */
29 	unsigned int cxx_info:1;	/* 23 */
30 	unsigned int cxx_try_catch:1;	/* 24 */
31 	unsigned int sched_entry_seq:1;	/* 25 */
32 	unsigned int reserved2:1;	/* 26 */
33 	unsigned int Save_SP:1;	/* 27 */
34 	unsigned int Save_RP:1;	/* 28 */
35 	unsigned int Save_MRP_in_frame:1;	/* 29 */
36 	unsigned int extn_ptr_defined:1;	/* 30 */
37 	unsigned int Cleanup_defined:1;	/* 31 */
38 
39 	unsigned int MPE_XL_interrupt_marker:1;	/* 0 */
40 	unsigned int HP_UX_interrupt_marker:1;	/* 1 */
41 	unsigned int Large_frame:1;	/* 2 */
42 	unsigned int Pseudo_SP_Set:1;	/* 3 */
43 	unsigned int reserved4:1;	/* 4 */
44 	unsigned int Total_frame_size:27;	/* 5..31 */
45 };
46 
47 struct unwind_table {
48 	struct list_head list;
49 	const char *name;
50 	unsigned long gp;
51 	unsigned long base_addr;
52 	unsigned long start;
53 	unsigned long end;
54 	const struct unwind_table_entry *table;
55 	unsigned long length;
56 };
57 
58 struct unwind_frame_info {
59 	struct task_struct *t;
60 	/* Eventually we would like to be able to get at any of the registers
61 	   available; but for now we only try to get the sp and ip for each
62 	   frame */
63 	/* struct pt_regs regs; */
64 	unsigned long sp, ip, rp, r31;
65 	unsigned long prev_sp, prev_ip;
66 };
67 
68 struct unwind_table *
69 unwind_table_add(const char *name, unsigned long base_addr,
70 		 unsigned long gp, void *start, void *end);
71 void
72 unwind_table_remove(struct unwind_table *table);
73 
74 void unwind_frame_init(struct unwind_frame_info *info, struct task_struct *t,
75 		       struct pt_regs *regs);
76 void unwind_frame_init_from_blocked_task(struct unwind_frame_info *info,
77 			struct task_struct *t);
78 void unwind_frame_init_task(struct unwind_frame_info *info,
79 			struct task_struct *task, struct pt_regs *regs);
80 int unwind_once(struct unwind_frame_info *info);
81 int unwind_to_user(struct unwind_frame_info *info);
82 
83 int unwind_init(void);
84 
85 #endif
86