1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright (C) 2012 Regents of the University of California
4 */
5
6 #ifndef _ASM_RISCV_PTRACE_H
7 #define _ASM_RISCV_PTRACE_H
8
9 #include <uapi/asm/ptrace.h>
10 #include <asm/csr.h>
11 #include <linux/compiler.h>
12
13 #ifndef __ASSEMBLY__
14
15 struct pt_regs {
16 unsigned long epc;
17 unsigned long ra;
18 unsigned long sp;
19 unsigned long gp;
20 unsigned long tp;
21 unsigned long t0;
22 unsigned long t1;
23 unsigned long t2;
24 unsigned long s0;
25 unsigned long s1;
26 unsigned long a0;
27 unsigned long a1;
28 unsigned long a2;
29 unsigned long a3;
30 unsigned long a4;
31 unsigned long a5;
32 unsigned long a6;
33 unsigned long a7;
34 unsigned long s2;
35 unsigned long s3;
36 unsigned long s4;
37 unsigned long s5;
38 unsigned long s6;
39 unsigned long s7;
40 unsigned long s8;
41 unsigned long s9;
42 unsigned long s10;
43 unsigned long s11;
44 unsigned long t3;
45 unsigned long t4;
46 unsigned long t5;
47 unsigned long t6;
48 /* Supervisor/Machine CSRs */
49 unsigned long status;
50 unsigned long badaddr;
51 unsigned long cause;
52 /* a0 value before the syscall */
53 unsigned long orig_a0;
54 };
55
56 #ifdef CONFIG_64BIT
57 #define REG_FMT "%016lx"
58 #else
59 #define REG_FMT "%08lx"
60 #endif
61
62 #define user_mode(regs) (((regs)->status & SR_PP) == 0)
63
64 #define MAX_REG_OFFSET offsetof(struct pt_regs, orig_a0)
65
66 /* Helpers for working with the instruction pointer */
instruction_pointer(struct pt_regs * regs)67 static inline unsigned long instruction_pointer(struct pt_regs *regs)
68 {
69 return regs->epc;
70 }
instruction_pointer_set(struct pt_regs * regs,unsigned long val)71 static inline void instruction_pointer_set(struct pt_regs *regs,
72 unsigned long val)
73 {
74 regs->epc = val;
75 }
76
77 #define profile_pc(regs) instruction_pointer(regs)
78
79 /* Helpers for working with the user stack pointer */
user_stack_pointer(struct pt_regs * regs)80 static inline unsigned long user_stack_pointer(struct pt_regs *regs)
81 {
82 return regs->sp;
83 }
user_stack_pointer_set(struct pt_regs * regs,unsigned long val)84 static inline void user_stack_pointer_set(struct pt_regs *regs,
85 unsigned long val)
86 {
87 regs->sp = val;
88 }
89
90 /* Valid only for Kernel mode traps. */
kernel_stack_pointer(struct pt_regs * regs)91 static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
92 {
93 return regs->sp;
94 }
95
96 /* Helpers for working with the frame pointer */
frame_pointer(struct pt_regs * regs)97 static inline unsigned long frame_pointer(struct pt_regs *regs)
98 {
99 return regs->s0;
100 }
frame_pointer_set(struct pt_regs * regs,unsigned long val)101 static inline void frame_pointer_set(struct pt_regs *regs,
102 unsigned long val)
103 {
104 regs->s0 = val;
105 }
106
regs_return_value(struct pt_regs * regs)107 static inline unsigned long regs_return_value(struct pt_regs *regs)
108 {
109 return regs->a0;
110 }
111
regs_set_return_value(struct pt_regs * regs,unsigned long val)112 static inline void regs_set_return_value(struct pt_regs *regs,
113 unsigned long val)
114 {
115 regs->a0 = val;
116 }
117
118 extern int regs_query_register_offset(const char *name);
119 extern unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
120 unsigned int n);
121
122 void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
123 unsigned long frame_pointer);
124 int do_syscall_trace_enter(struct pt_regs *regs);
125 void do_syscall_trace_exit(struct pt_regs *regs);
126
127 /**
128 * regs_get_register() - get register value from its offset
129 * @regs: pt_regs from which register value is gotten
130 * @offset: offset of the register.
131 *
132 * regs_get_register returns the value of a register whose offset from @regs.
133 * The @offset is the offset of the register in struct pt_regs.
134 * If @offset is bigger than MAX_REG_OFFSET, this returns 0.
135 */
regs_get_register(struct pt_regs * regs,unsigned int offset)136 static inline unsigned long regs_get_register(struct pt_regs *regs,
137 unsigned int offset)
138 {
139 if (unlikely(offset > MAX_REG_OFFSET))
140 return 0;
141
142 return *(unsigned long *)((unsigned long)regs + offset);
143 }
144
145 /**
146 * regs_get_kernel_argument() - get Nth function argument in kernel
147 * @regs: pt_regs of that context
148 * @n: function argument number (start from 0)
149 *
150 * regs_get_argument() returns @n th argument of the function call.
151 *
152 * Note you can get the parameter correctly if the function has no
153 * more than eight arguments.
154 */
regs_get_kernel_argument(struct pt_regs * regs,unsigned int n)155 static inline unsigned long regs_get_kernel_argument(struct pt_regs *regs,
156 unsigned int n)
157 {
158 static const int nr_reg_arguments = 8;
159 static const unsigned int argument_offs[] = {
160 offsetof(struct pt_regs, a0),
161 offsetof(struct pt_regs, a1),
162 offsetof(struct pt_regs, a2),
163 offsetof(struct pt_regs, a3),
164 offsetof(struct pt_regs, a4),
165 offsetof(struct pt_regs, a5),
166 offsetof(struct pt_regs, a6),
167 offsetof(struct pt_regs, a7),
168 };
169
170 if (n < nr_reg_arguments)
171 return regs_get_register(regs, argument_offs[n]);
172 return 0;
173 }
174
175 #endif /* __ASSEMBLY__ */
176
177 #endif /* _ASM_RISCV_PTRACE_H */
178