1 #ifndef _ASM_IA64_UNWIND_H
2 #define _ASM_IA64_UNWIND_H
3 
4 /*
5  * Copyright (C) 1999-2000, 2003 Hewlett-Packard Co
6  *	David Mosberger-Tang <davidm@hpl.hp.com>
7  *
8  * A simple API for unwinding kernel stacks.  This is used for
9  * debugging and error reporting purposes.  The kernel doesn't need
10  * full-blown stack unwinding with all the bells and whitles, so there
11  * is not much point in implementing the full IA-64 unwind API (though
12  * it would of course be possible to implement the kernel API on top
13  * of it).
14  */
15 
16 struct task_struct;	/* forward declaration */
17 struct switch_stack;	/* forward declaration */
18 
19 enum unw_application_register {
20 	UNW_AR_BSP,
21 	UNW_AR_BSPSTORE,
22 	UNW_AR_PFS,
23 	UNW_AR_RNAT,
24 	UNW_AR_UNAT,
25 	UNW_AR_LC,
26 	UNW_AR_EC,
27 	UNW_AR_FPSR,
28 	UNW_AR_RSC,
29 	UNW_AR_CCV,
30 	UNW_AR_CSD,
31 	UNW_AR_SSD
32 };
33 
34 /*
35  * The following declarations are private to the unwind
36  * implementation:
37  */
38 
39 struct unw_stack {
40 	unsigned long limit;
41 	unsigned long top;
42 };
43 
44 #define UNW_FLAG_INTERRUPT_FRAME	(1UL << 0)
45 
46 /*
47  * No user of this module should every access this structure directly
48  * as it is subject to change.  It is declared here solely so we can
49  * use automatic variables.
50  */
51 struct unw_frame_info {
52 	struct unw_stack regstk;
53 	struct unw_stack memstk;
54 	unsigned int flags;
55 	short hint;
56 	short prev_script;
57 
58 	/* current frame info: */
59 	unsigned long bsp;		/* backing store pointer value */
60 	unsigned long sp;		/* stack pointer value */
61 	unsigned long psp;		/* previous sp value */
62 	unsigned long ip;		/* instruction pointer value */
63 	unsigned long pr;		/* current predicate values */
64 	unsigned long *cfm_loc;		/* cfm save location (or NULL) */
65 	unsigned long pt;		/* struct pt_regs location */
66 
67 	struct task_struct *task;
68 	struct switch_stack *sw;
69 
70 	/* preserved state: */
71 	unsigned long *bsp_loc;		/* previous bsp save location */
72 	unsigned long *bspstore_loc;
73 	unsigned long *pfs_loc;
74 	unsigned long *rnat_loc;
75 	unsigned long *rp_loc;
76 	unsigned long *pri_unat_loc;
77 	unsigned long *unat_loc;
78 	unsigned long *pr_loc;
79 	unsigned long *lc_loc;
80 	unsigned long *fpsr_loc;
81 	struct unw_ireg {
82 		unsigned long *loc;
83 		struct unw_ireg_nat {
84 			long type : 3;			/* enum unw_nat_type */
85 			signed long off : 61;		/* NaT word is at loc+nat.off */
86 		} nat;
87 	} r4, r5, r6, r7;
88 	unsigned long *b1_loc, *b2_loc, *b3_loc, *b4_loc, *b5_loc;
89 	struct ia64_fpreg *f2_loc, *f3_loc, *f4_loc, *f5_loc, *fr_loc[16];
90 };
91 
92 /*
93  * The official API follows below:
94  */
95 
96 struct unw_table_entry {
97 	u64 start_offset;
98 	u64 end_offset;
99 	u64 info_offset;
100 };
101 
102 /*
103  * Initialize unwind support.
104  */
105 extern void unw_init (void);
106 extern void unw_create_gate_table (void);
107 
108 extern 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 
111 extern void unw_remove_unwind_table (void *handle);
112 
113 /*
114  * Prepare to unwind blocked task t.
115  */
116 extern void unw_init_from_blocked_task (struct unw_frame_info *info, struct task_struct *t);
117 
118 /*
119  * Prepare to unwind from interruption.  The pt-regs and switch-stack structures must have
120  * be "adjacent" (no state modifications between pt-regs and switch-stack).
121  */
122 extern void unw_init_from_interruption (struct unw_frame_info *info, struct task_struct *t,
123 					struct pt_regs *pt, struct switch_stack *sw);
124 
125 extern void unw_init_frame_info (struct unw_frame_info *info, struct task_struct *t,
126 				 struct switch_stack *sw);
127 
128 /*
129  * Prepare to unwind the currently running thread.
130  */
131 extern void unw_init_running (void (*callback)(struct unw_frame_info *info, void *arg), void *arg);
132 
133 /*
134  * Unwind to previous to frame.  Returns 0 if successful, negative
135  * number in case of an error.
136  */
137 extern int unw_unwind (struct unw_frame_info *info);
138 
139 /*
140  * Unwind until the return pointer is in user-land (or until an error
141  * occurs).  Returns 0 if successful, negative number in case of
142  * error.
143  */
144 extern int unw_unwind_to_user (struct unw_frame_info *info);
145 
146 #define unw_is_intr_frame(info)	(((info)->flags & UNW_FLAG_INTERRUPT_FRAME) != 0)
147 
148 static inline int
unw_get_ip(struct unw_frame_info * info,unsigned long * valp)149 unw_get_ip (struct unw_frame_info *info, unsigned long *valp)
150 {
151 	*valp = (info)->ip;
152 	return 0;
153 }
154 
155 static inline int
unw_get_sp(struct unw_frame_info * info,unsigned long * valp)156 unw_get_sp (struct unw_frame_info *info, unsigned long *valp)
157 {
158 	*valp = (info)->sp;
159 	return 0;
160 }
161 
162 static inline int
unw_get_psp(struct unw_frame_info * info,unsigned long * valp)163 unw_get_psp (struct unw_frame_info *info, unsigned long *valp)
164 {
165 	*valp = (info)->psp;
166 	return 0;
167 }
168 
169 static inline int
unw_get_bsp(struct unw_frame_info * info,unsigned long * valp)170 unw_get_bsp (struct unw_frame_info *info, unsigned long *valp)
171 {
172 	*valp = (info)->bsp;
173 	return 0;
174 }
175 
176 static inline int
unw_get_cfm(struct unw_frame_info * info,unsigned long * valp)177 unw_get_cfm (struct unw_frame_info *info, unsigned long *valp)
178 {
179 	*valp = *(info)->cfm_loc;
180 	return 0;
181 }
182 
183 static inline int
unw_set_cfm(struct unw_frame_info * info,unsigned long val)184 unw_set_cfm (struct unw_frame_info *info, unsigned long val)
185 {
186 	*(info)->cfm_loc = val;
187 	return 0;
188 }
189 
190 static inline int
unw_get_rp(struct unw_frame_info * info,unsigned long * val)191 unw_get_rp (struct unw_frame_info *info, unsigned long *val)
192 {
193 	if (!info->rp_loc)
194 		return -1;
195 	*val = *info->rp_loc;
196 	return 0;
197 }
198 
199 extern int unw_access_gr (struct unw_frame_info *, int, unsigned long *, char *, int);
200 extern int unw_access_br (struct unw_frame_info *, int, unsigned long *, int);
201 extern int unw_access_fr (struct unw_frame_info *, int, struct ia64_fpreg *, int);
202 extern int unw_access_ar (struct unw_frame_info *, int, unsigned long *, int);
203 extern int unw_access_pr (struct unw_frame_info *, unsigned long *, int);
204 
205 static inline int
unw_set_gr(struct unw_frame_info * i,int n,unsigned long v,char nat)206 unw_set_gr (struct unw_frame_info *i, int n, unsigned long v, char nat)
207 {
208 	return unw_access_gr(i, n, &v, &nat, 1);
209 }
210 
211 static inline int
unw_set_br(struct unw_frame_info * i,int n,unsigned long v)212 unw_set_br (struct unw_frame_info *i, int n, unsigned long v)
213 {
214 	return unw_access_br(i, n, &v, 1);
215 }
216 
217 static inline int
unw_set_fr(struct unw_frame_info * i,int n,struct ia64_fpreg v)218 unw_set_fr (struct unw_frame_info *i, int n, struct ia64_fpreg v)
219 {
220 	return unw_access_fr(i, n, &v, 1);
221 }
222 
223 static inline int
unw_set_ar(struct unw_frame_info * i,int n,unsigned long v)224 unw_set_ar (struct unw_frame_info *i, int n, unsigned long v)
225 {
226 	return unw_access_ar(i, n, &v, 1);
227 }
228 
229 static inline int
unw_set_pr(struct unw_frame_info * i,unsigned long v)230 unw_set_pr (struct unw_frame_info *i, unsigned long v)
231 {
232 	return unw_access_pr(i, &v, 1);
233 }
234 
235 #define unw_get_gr(i,n,v,nat)	unw_access_gr(i,n,v,nat,0)
236 #define unw_get_br(i,n,v)	unw_access_br(i,n,v,0)
237 #define unw_get_fr(i,n,v)	unw_access_fr(i,n,v,0)
238 #define unw_get_ar(i,n,v)	unw_access_ar(i,n,v,0)
239 #define unw_get_pr(i,v)		unw_access_pr(i,v,0)
240 
241 #endif /* _ASM_UNWIND_H */
242