1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_S390_STACKTRACE_H
3 #define _ASM_S390_STACKTRACE_H
4
5 #include <linux/stacktrace.h>
6 #include <linux/uaccess.h>
7 #include <linux/ptrace.h>
8
9 struct stack_frame_user {
10 unsigned long back_chain;
11 unsigned long empty1[5];
12 unsigned long gprs[10];
13 unsigned long empty2[4];
14 };
15
16 struct stack_frame_vdso_wrapper {
17 struct stack_frame_user sf;
18 unsigned long return_address;
19 };
20
21 struct perf_callchain_entry_ctx;
22
23 void arch_stack_walk_user_common(stack_trace_consume_fn consume_entry, void *cookie,
24 struct perf_callchain_entry_ctx *entry,
25 const struct pt_regs *regs, bool perf);
26
27 enum stack_type {
28 STACK_TYPE_UNKNOWN,
29 STACK_TYPE_TASK,
30 STACK_TYPE_IRQ,
31 STACK_TYPE_NODAT,
32 STACK_TYPE_RESTART,
33 STACK_TYPE_MCCK,
34 };
35
36 struct stack_info {
37 enum stack_type type;
38 unsigned long begin, end;
39 };
40
41 const char *stack_type_name(enum stack_type type);
42 int get_stack_info(unsigned long sp, struct task_struct *task,
43 struct stack_info *info, unsigned long *visit_mask);
44
on_stack(struct stack_info * info,unsigned long addr,size_t len)45 static inline bool on_stack(struct stack_info *info,
46 unsigned long addr, size_t len)
47 {
48 if (info->type == STACK_TYPE_UNKNOWN)
49 return false;
50 if (addr + len < addr)
51 return false;
52 return addr >= info->begin && addr + len <= info->end;
53 }
54
55 /*
56 * Stack layout of a C stack frame.
57 * Kernel uses the packed stack layout (-mpacked-stack).
58 */
59 struct stack_frame {
60 union {
61 unsigned long empty[9];
62 struct {
63 unsigned long sie_control_block;
64 unsigned long sie_savearea;
65 unsigned long sie_reason;
66 unsigned long sie_flags;
67 unsigned long sie_control_block_phys;
68 unsigned long sie_guest_asce;
69 unsigned long sie_irq;
70 };
71 };
72 unsigned long gprs[10];
73 unsigned long back_chain;
74 };
75
76 /*
77 * Unlike current_stack_pointer which simply contains the current value of %r15
78 * current_frame_address() returns function stack frame address, which matches
79 * %r15 upon function invocation. It may differ from %r15 later if function
80 * allocates stack for local variables or new stack frame to call other
81 * functions.
82 */
83 #define current_frame_address() \
84 ((unsigned long)__builtin_frame_address(0) - \
85 offsetof(struct stack_frame, back_chain))
86
get_stack_pointer(struct task_struct * task,struct pt_regs * regs)87 static __always_inline unsigned long get_stack_pointer(struct task_struct *task,
88 struct pt_regs *regs)
89 {
90 if (regs)
91 return (unsigned long)kernel_stack_pointer(regs);
92 if (task == current)
93 return current_frame_address();
94 return (unsigned long)task->thread.ksp;
95 }
96
97 /*
98 * To keep this simple mark register 2-6 as being changed (volatile)
99 * by the called function, even though register 6 is saved/nonvolatile.
100 */
101 #define CALL_FMT_0 "=&d" (r2)
102 #define CALL_FMT_1 "+&d" (r2)
103 #define CALL_FMT_2 CALL_FMT_1, "+&d" (r3)
104 #define CALL_FMT_3 CALL_FMT_2, "+&d" (r4)
105 #define CALL_FMT_4 CALL_FMT_3, "+&d" (r5)
106 #define CALL_FMT_5 CALL_FMT_4, "+&d" (r6)
107
108 #define CALL_CLOBBER_5 "0", "1", "14", "cc", "memory"
109 #define CALL_CLOBBER_4 CALL_CLOBBER_5
110 #define CALL_CLOBBER_3 CALL_CLOBBER_4, "5"
111 #define CALL_CLOBBER_2 CALL_CLOBBER_3, "4"
112 #define CALL_CLOBBER_1 CALL_CLOBBER_2, "3"
113 #define CALL_CLOBBER_0 CALL_CLOBBER_1
114
115 #define CALL_LARGS_0(...) \
116 long dummy = 0
117 #define CALL_LARGS_1(t1, a1) \
118 long arg1 = (long)(t1)(a1)
119 #define CALL_LARGS_2(t1, a1, t2, a2) \
120 CALL_LARGS_1(t1, a1); \
121 long arg2 = (long)(t2)(a2)
122 #define CALL_LARGS_3(t1, a1, t2, a2, t3, a3) \
123 CALL_LARGS_2(t1, a1, t2, a2); \
124 long arg3 = (long)(t3)(a3)
125 #define CALL_LARGS_4(t1, a1, t2, a2, t3, a3, t4, a4) \
126 CALL_LARGS_3(t1, a1, t2, a2, t3, a3); \
127 long arg4 = (long)(t4)(a4)
128 #define CALL_LARGS_5(t1, a1, t2, a2, t3, a3, t4, a4, t5, a5) \
129 CALL_LARGS_4(t1, a1, t2, a2, t3, a3, t4, a4); \
130 long arg5 = (long)(t5)(a5)
131
132 #define CALL_REGS_0 \
133 register long r2 asm("2") = dummy
134 #define CALL_REGS_1 \
135 register long r2 asm("2") = arg1
136 #define CALL_REGS_2 \
137 CALL_REGS_1; \
138 register long r3 asm("3") = arg2
139 #define CALL_REGS_3 \
140 CALL_REGS_2; \
141 register long r4 asm("4") = arg3
142 #define CALL_REGS_4 \
143 CALL_REGS_3; \
144 register long r5 asm("5") = arg4
145 #define CALL_REGS_5 \
146 CALL_REGS_4; \
147 register long r6 asm("6") = arg5
148
149 #define CALL_TYPECHECK_0(...)
150 #define CALL_TYPECHECK_1(t, a, ...) \
151 typecheck(t, a)
152 #define CALL_TYPECHECK_2(t, a, ...) \
153 CALL_TYPECHECK_1(__VA_ARGS__); \
154 typecheck(t, a)
155 #define CALL_TYPECHECK_3(t, a, ...) \
156 CALL_TYPECHECK_2(__VA_ARGS__); \
157 typecheck(t, a)
158 #define CALL_TYPECHECK_4(t, a, ...) \
159 CALL_TYPECHECK_3(__VA_ARGS__); \
160 typecheck(t, a)
161 #define CALL_TYPECHECK_5(t, a, ...) \
162 CALL_TYPECHECK_4(__VA_ARGS__); \
163 typecheck(t, a)
164
165 #define CALL_PARM_0(...) void
166 #define CALL_PARM_1(t, a, ...) t
167 #define CALL_PARM_2(t, a, ...) t, CALL_PARM_1(__VA_ARGS__)
168 #define CALL_PARM_3(t, a, ...) t, CALL_PARM_2(__VA_ARGS__)
169 #define CALL_PARM_4(t, a, ...) t, CALL_PARM_3(__VA_ARGS__)
170 #define CALL_PARM_5(t, a, ...) t, CALL_PARM_4(__VA_ARGS__)
171 #define CALL_PARM_6(t, a, ...) t, CALL_PARM_5(__VA_ARGS__)
172
173 /*
174 * Use call_on_stack() to call a function switching to a specified
175 * stack. Proper sign and zero extension of function arguments is
176 * done. Usage:
177 *
178 * rc = call_on_stack(nr, stack, rettype, fn, t1, a1, t2, a2, ...)
179 *
180 * - nr specifies the number of function arguments of fn.
181 * - stack specifies the stack to be used.
182 * - fn is the function to be called.
183 * - rettype is the return type of fn.
184 * - t1, a1, ... are pairs, where t1 must match the type of the first
185 * argument of fn, t2 the second, etc. a1 is the corresponding
186 * first function argument (not name), etc.
187 */
188 #define call_on_stack(nr, stack, rettype, fn, ...) \
189 ({ \
190 rettype (*__fn)(CALL_PARM_##nr(__VA_ARGS__)) = fn; \
191 unsigned long frame = current_frame_address(); \
192 unsigned long __stack = stack; \
193 unsigned long prev; \
194 CALL_LARGS_##nr(__VA_ARGS__); \
195 CALL_REGS_##nr; \
196 \
197 CALL_TYPECHECK_##nr(__VA_ARGS__); \
198 asm volatile( \
199 " lgr %[_prev],15\n" \
200 " lg 15,%[_stack]\n" \
201 " stg %[_frame],%[_bc](15)\n" \
202 " brasl 14,%[_fn]\n" \
203 " lgr 15,%[_prev]" \
204 : [_prev] "=&d" (prev), CALL_FMT_##nr \
205 : [_stack] "R" (__stack), \
206 [_bc] "i" (offsetof(struct stack_frame, back_chain)), \
207 [_frame] "d" (frame), \
208 [_fn] "X" (__fn) : CALL_CLOBBER_##nr); \
209 (rettype)r2; \
210 })
211
212 /*
213 * Use call_nodat() to call a function with DAT disabled.
214 * Proper sign and zero extension of function arguments is done.
215 * Usage:
216 *
217 * rc = call_nodat(nr, rettype, fn, t1, a1, t2, a2, ...)
218 *
219 * - nr specifies the number of function arguments of fn.
220 * - fn is the function to be called, where fn is a physical address.
221 * - rettype is the return type of fn.
222 * - t1, a1, ... are pairs, where t1 must match the type of the first
223 * argument of fn, t2 the second, etc. a1 is the corresponding
224 * first function argument (not name), etc.
225 *
226 * fn() is called with standard C function call ABI, with the exception
227 * that no useful stackframe or stackpointer is passed via register 15.
228 * Therefore the called function must not use r15 to access the stack.
229 */
230 #define call_nodat(nr, rettype, fn, ...) \
231 ({ \
232 rettype (*__fn)(CALL_PARM_##nr(__VA_ARGS__)) = (fn); \
233 /* aligned since psw_leave must not cross page boundary */ \
234 psw_t __aligned(16) psw_leave; \
235 psw_t psw_enter; \
236 CALL_LARGS_##nr(__VA_ARGS__); \
237 CALL_REGS_##nr; \
238 \
239 CALL_TYPECHECK_##nr(__VA_ARGS__); \
240 psw_enter.mask = PSW_KERNEL_BITS & ~PSW_MASK_DAT; \
241 psw_enter.addr = (unsigned long)__fn; \
242 asm volatile( \
243 " epsw 0,1\n" \
244 " risbg 1,0,0,31,32\n" \
245 " larl 7,1f\n" \
246 " stg 1,%[psw_leave]\n" \
247 " stg 7,8+%[psw_leave]\n" \
248 " la 7,%[psw_leave]\n" \
249 " lra 7,0(7)\n" \
250 " larl 1,0f\n" \
251 " lra 14,0(1)\n" \
252 " lpswe %[psw_enter]\n" \
253 "0: lpswe 0(7)\n" \
254 "1:" \
255 : CALL_FMT_##nr, [psw_leave] "=Q" (psw_leave) \
256 : [psw_enter] "Q" (psw_enter) \
257 : "7", CALL_CLOBBER_##nr); \
258 (rettype)r2; \
259 })
260
261 #endif /* _ASM_S390_STACKTRACE_H */
262