xref: /openbmc/linux/arch/riscv/include/asm/ptrace.h (revision cabce92d)
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 */
70 static inline unsigned long instruction_pointer(struct pt_regs *regs)
71 {
72 	return regs->epc;
73 }
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 */
83 static inline unsigned long user_stack_pointer(struct pt_regs *regs)
84 {
85 	return regs->sp;
86 }
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. */
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 */
100 static inline unsigned long frame_pointer(struct pt_regs *regs)
101 {
102 	return regs->s0;
103 }
104 static inline void frame_pointer_set(struct pt_regs *regs,
105 				     unsigned long val)
106 {
107 	regs->s0 = val;
108 }
109 
110 static inline unsigned long regs_return_value(struct pt_regs *regs)
111 {
112 	return regs->a0;
113 }
114 
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  */
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  */
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 
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