1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_IA64_UNWIND_H
3#define _ASM_IA64_UNWIND_H
4
5/*
6 * Copyright (C) 1999-2000, 2003 Hewlett-Packard Co
7 *	David Mosberger-Tang <davidm@hpl.hp.com>
8 *
9 * A simple API for unwinding kernel stacks.  This is used for
10 * debugging and error reporting purposes.  The kernel doesn't need
11 * full-blown stack unwinding with all the bells and whitles, so there
12 * is not much point in implementing the full IA-64 unwind API (though
13 * it would of course be possible to implement the kernel API on top
14 * of it).
15 */
16
17struct task_struct;	/* forward declaration */
18struct switch_stack;	/* forward declaration */
19
20enum unw_application_register {
21	UNW_AR_BSP,
22	UNW_AR_BSPSTORE,
23	UNW_AR_PFS,
24	UNW_AR_RNAT,
25	UNW_AR_UNAT,
26	UNW_AR_LC,
27	UNW_AR_EC,
28	UNW_AR_FPSR,
29	UNW_AR_RSC,
30	UNW_AR_CCV,
31	UNW_AR_CSD,
32	UNW_AR_SSD
33};
34
35/*
36 * The following declarations are private to the unwind
37 * implementation:
38 */
39
40struct unw_stack {
41	unsigned long limit;
42	unsigned long top;
43};
44
45#define UNW_FLAG_INTERRUPT_FRAME	(1UL << 0)
46
47/*
48 * No user of this module should every access this structure directly
49 * as it is subject to change.  It is declared here solely so we can
50 * use automatic variables.
51 */
52struct unw_frame_info {
53	struct unw_stack regstk;
54	struct unw_stack memstk;
55	unsigned int flags;
56	short hint;
57	short prev_script;
58
59	/* current frame info: */
60	unsigned long bsp;		/* backing store pointer value */
61	unsigned long sp;		/* stack pointer value */
62	unsigned long psp;		/* previous sp value */
63	unsigned long ip;		/* instruction pointer value */
64	unsigned long pr;		/* current predicate values */
65	unsigned long *cfm_loc;		/* cfm save location (or NULL) */
66	unsigned long pt;		/* struct pt_regs location */
67
68	struct task_struct *task;
69	struct switch_stack *sw;
70
71	/* preserved state: */
72	unsigned long *bsp_loc;		/* previous bsp save location */
73	unsigned long *bspstore_loc;
74	unsigned long *pfs_loc;
75	unsigned long *rnat_loc;
76	unsigned long *rp_loc;
77	unsigned long *pri_unat_loc;
78	unsigned long *unat_loc;
79	unsigned long *pr_loc;
80	unsigned long *lc_loc;
81	unsigned long *fpsr_loc;
82	struct unw_ireg {
83		unsigned long *loc;
84		struct unw_ireg_nat {
85			unsigned long type : 3;		/* enum unw_nat_type */
86			signed long off : 61;		/* NaT word is at loc+nat.off */
87		} nat;
88	} r4, r5, r6, r7;
89	unsigned long *b1_loc, *b2_loc, *b3_loc, *b4_loc, *b5_loc;
90	struct ia64_fpreg *f2_loc, *f3_loc, *f4_loc, *f5_loc, *fr_loc[16];
91};
92
93/*
94 * The official API follows below:
95 */
96
97struct unw_table_entry {
98	u64 start_offset;
99	u64 end_offset;
100	u64 info_offset;
101};
102
103/*
104 * Initialize unwind support.
105 */
106extern void unw_init (void);
107
108extern void *unw_add_unwind_table (const char *name, unsigned long segment_base, unsigned long gp,
109				   const void *table_start, const void *table_end);
110
111extern void unw_remove_unwind_table (void *handle);
112
113/*
114 * Prepare to unwind blocked task t.
115 */
116extern void unw_init_from_blocked_task (struct unw_frame_info *info, struct task_struct *t);
117
118extern void unw_init_frame_info (struct unw_frame_info *info, struct task_struct *t,
119				 struct switch_stack *sw);
120
121/*
122 * Prepare to unwind the currently running thread.
123 */
124extern void unw_init_running (void (*callback)(struct unw_frame_info *info, void *arg), void *arg);
125
126/*
127 * Unwind to previous to frame.  Returns 0 if successful, negative
128 * number in case of an error.
129 */
130extern int unw_unwind (struct unw_frame_info *info);
131
132/*
133 * Unwind until the return pointer is in user-land (or until an error
134 * occurs).  Returns 0 if successful, negative number in case of
135 * error.
136 */
137extern int unw_unwind_to_user (struct unw_frame_info *info);
138
139#define unw_is_intr_frame(info)	(((info)->flags & UNW_FLAG_INTERRUPT_FRAME) != 0)
140
141static inline int
142unw_get_ip (struct unw_frame_info *info, unsigned long *valp)
143{
144	*valp = (info)->ip;
145	return 0;
146}
147
148static inline int
149unw_get_sp (struct unw_frame_info *info, unsigned long *valp)
150{
151	*valp = (info)->sp;
152	return 0;
153}
154
155static inline int
156unw_get_psp (struct unw_frame_info *info, unsigned long *valp)
157{
158	*valp = (info)->psp;
159	return 0;
160}
161
162static inline int
163unw_get_bsp (struct unw_frame_info *info, unsigned long *valp)
164{
165	*valp = (info)->bsp;
166	return 0;
167}
168
169static inline int
170unw_get_cfm (struct unw_frame_info *info, unsigned long *valp)
171{
172	*valp = *(info)->cfm_loc;
173	return 0;
174}
175
176static inline int
177unw_set_cfm (struct unw_frame_info *info, unsigned long val)
178{
179	*(info)->cfm_loc = val;
180	return 0;
181}
182
183static inline int
184unw_get_rp (struct unw_frame_info *info, unsigned long *val)
185{
186	if (!info->rp_loc)
187		return -1;
188	*val = *info->rp_loc;
189	return 0;
190}
191
192extern int unw_access_gr (struct unw_frame_info *, int, unsigned long *, char *, int);
193extern int unw_access_br (struct unw_frame_info *, int, unsigned long *, int);
194extern int unw_access_fr (struct unw_frame_info *, int, struct ia64_fpreg *, int);
195extern int unw_access_ar (struct unw_frame_info *, int, unsigned long *, int);
196extern int unw_access_pr (struct unw_frame_info *, unsigned long *, int);
197
198static inline int
199unw_set_gr (struct unw_frame_info *i, int n, unsigned long v, char nat)
200{
201	return unw_access_gr(i, n, &v, &nat, 1);
202}
203
204static inline int
205unw_set_br (struct unw_frame_info *i, int n, unsigned long v)
206{
207	return unw_access_br(i, n, &v, 1);
208}
209
210static inline int
211unw_set_fr (struct unw_frame_info *i, int n, struct ia64_fpreg v)
212{
213	return unw_access_fr(i, n, &v, 1);
214}
215
216static inline int
217unw_set_ar (struct unw_frame_info *i, int n, unsigned long v)
218{
219	return unw_access_ar(i, n, &v, 1);
220}
221
222static inline int
223unw_set_pr (struct unw_frame_info *i, unsigned long v)
224{
225	return unw_access_pr(i, &v, 1);
226}
227
228#define unw_get_gr(i,n,v,nat)	unw_access_gr(i,n,v,nat,0)
229#define unw_get_br(i,n,v)	unw_access_br(i,n,v,0)
230#define unw_get_fr(i,n,v)	unw_access_fr(i,n,v,0)
231#define unw_get_ar(i,n,v)	unw_access_ar(i,n,v,0)
232#define unw_get_pr(i,v)		unw_access_pr(i,v,0)
233
234#endif /* _ASM_UNWIND_H */
235