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