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 #define PTRACE_SYSEMU 0x1f
57 #define PTRACE_SYSEMU_SINGLESTEP 0x20
58
59 #ifdef CONFIG_64BIT
60 #define REG_FMT "%016lx"
61 #else
62 #define REG_FMT "%08lx"
63 #endif
64
65 #define user_mode(regs) (((regs)->status & SR_PP) == 0)
66
67 #define MAX_REG_OFFSET offsetof(struct pt_regs, orig_a0)
68
69 /* Helpers for working with the instruction pointer */
instruction_pointer(struct pt_regs * regs)70 static inline unsigned long instruction_pointer(struct pt_regs *regs)
71 {
72 return regs->epc;
73 }
instruction_pointer_set(struct pt_regs * regs,unsigned long val)74 static inline void instruction_pointer_set(struct pt_regs *regs,
75 unsigned long val)
76 {
77 regs->epc = val;
78 }
79
80 #define profile_pc(regs) instruction_pointer(regs)
81
82 /* Helpers for working with the user stack pointer */
user_stack_pointer(struct pt_regs * regs)83 static inline unsigned long user_stack_pointer(struct pt_regs *regs)
84 {
85 return regs->sp;
86 }
user_stack_pointer_set(struct pt_regs * regs,unsigned long val)87 static inline void user_stack_pointer_set(struct pt_regs *regs,
88 unsigned long val)
89 {
90 regs->sp = val;
91 }
92
93 /* Valid only for Kernel mode traps. */
kernel_stack_pointer(struct pt_regs * regs)94 static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
95 {
96 return regs->sp;
97 }
98
99 /* Helpers for working with the frame pointer */
frame_pointer(struct pt_regs * regs)100 static inline unsigned long frame_pointer(struct pt_regs *regs)
101 {
102 return regs->s0;
103 }
frame_pointer_set(struct pt_regs * regs,unsigned long val)104 static inline void frame_pointer_set(struct pt_regs *regs,
105 unsigned long val)
106 {
107 regs->s0 = val;
108 }
109
regs_return_value(struct pt_regs * regs)110 static inline unsigned long regs_return_value(struct pt_regs *regs)
111 {
112 return regs->a0;
113 }
114
regs_set_return_value(struct pt_regs * regs,unsigned long val)115 static inline void regs_set_return_value(struct pt_regs *regs,
116 unsigned long val)
117 {
118 regs->a0 = val;
119 }
120
121 extern int regs_query_register_offset(const char *name);
122 extern unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
123 unsigned int n);
124
125 void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
126 unsigned long frame_pointer);
127
128 /**
129 * regs_get_register() - get register value from its offset
130 * @regs: pt_regs from which register value is gotten
131 * @offset: offset of the register.
132 *
133 * regs_get_register returns the value of a register whose offset from @regs.
134 * The @offset is the offset of the register in struct pt_regs.
135 * If @offset is bigger than MAX_REG_OFFSET, this returns 0.
136 */
regs_get_register(struct pt_regs * regs,unsigned int offset)137 static inline unsigned long regs_get_register(struct pt_regs *regs,
138 unsigned int offset)
139 {
140 if (unlikely(offset > MAX_REG_OFFSET))
141 return 0;
142
143 return *(unsigned long *)((unsigned long)regs + offset);
144 }
145
146 /**
147 * regs_get_kernel_argument() - get Nth function argument in kernel
148 * @regs: pt_regs of that context
149 * @n: function argument number (start from 0)
150 *
151 * regs_get_argument() returns @n th argument of the function call.
152 *
153 * Note you can get the parameter correctly if the function has no
154 * more than eight arguments.
155 */
regs_get_kernel_argument(struct pt_regs * regs,unsigned int n)156 static inline unsigned long regs_get_kernel_argument(struct pt_regs *regs,
157 unsigned int n)
158 {
159 static const int nr_reg_arguments = 8;
160 static const unsigned int argument_offs[] = {
161 offsetof(struct pt_regs, a0),
162 offsetof(struct pt_regs, a1),
163 offsetof(struct pt_regs, a2),
164 offsetof(struct pt_regs, a3),
165 offsetof(struct pt_regs, a4),
166 offsetof(struct pt_regs, a5),
167 offsetof(struct pt_regs, a6),
168 offsetof(struct pt_regs, a7),
169 };
170
171 if (n < nr_reg_arguments)
172 return regs_get_register(regs, argument_offs[n]);
173 return 0;
174 }
175
regs_irqs_disabled(struct pt_regs * regs)176 static inline int regs_irqs_disabled(struct pt_regs *regs)
177 {
178 return !(regs->status & SR_PIE);
179 }
180
181 #endif /* __ASSEMBLY__ */
182
183 #endif /* _ASM_RISCV_PTRACE_H */
184