ptrace.h

  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 __ASSEMBLER__
 14
 15struct 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	struct_group(a_regs,
 27		unsigned long a0;
 28		unsigned long a1;
 29		unsigned long a2;
 30		unsigned long a3;
 31		unsigned long a4;
 32		unsigned long a5;
 33		unsigned long a6;
 34		unsigned long a7;
 35	);
 36	unsigned long s2;
 37	unsigned long s3;
 38	unsigned long s4;
 39	unsigned long s5;
 40	unsigned long s6;
 41	unsigned long s7;
 42	unsigned long s8;
 43	unsigned long s9;
 44	unsigned long s10;
 45	unsigned long s11;
 46	unsigned long t3;
 47	unsigned long t4;
 48	unsigned long t5;
 49	unsigned long t6;
 50	/* Supervisor/Machine CSRs */
 51	unsigned long status;
 52	unsigned long badaddr;
 53	unsigned long cause;
 54	/* a0 value before the syscall */
 55	unsigned long orig_a0;
 56};
 57
 58#define PTRACE_SYSEMU			0x1f
 59#define PTRACE_SYSEMU_SINGLESTEP	0x20
 60
 61#ifdef CONFIG_64BIT
 62#define REG_FMT "%016lx"
 63#else
 64#define REG_FMT "%08lx"
 65#endif
 66
 67#define user_mode(regs) (((regs)->status & SR_PP) == 0)
 68
 69#define MAX_REG_OFFSET offsetof(struct pt_regs, orig_a0)
 70
 71/* Helpers for working with the instruction pointer */
 72static inline unsigned long instruction_pointer(struct pt_regs *regs)
 73{
 74	return regs->epc;
 75}
 76static inline void instruction_pointer_set(struct pt_regs *regs,
 77					   unsigned long val)
 78{
 79	regs->epc = val;
 80}
 81
 82#define profile_pc(regs) instruction_pointer(regs)
 83
 84/* Helpers for working with the user stack pointer */
 85static inline unsigned long user_stack_pointer(struct pt_regs *regs)
 86{
 87	return regs->sp;
 88}
 89static inline void user_stack_pointer_set(struct pt_regs *regs,
 90					  unsigned long val)
 91{
 92	regs->sp =  val;
 93}
 94
 95/* Valid only for Kernel mode traps. */
 96static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
 97{
 98	return regs->sp;
 99}
100
101/* Helpers for working with the frame pointer */
102static inline unsigned long frame_pointer(struct pt_regs *regs)
103{
104	return regs->s0;
105}
106static inline void frame_pointer_set(struct pt_regs *regs,
107				     unsigned long val)
108{
109	regs->s0 = val;
110}
111
112static inline unsigned long regs_return_value(struct pt_regs *regs)
113{
114	return regs->a0;
115}
116
117static inline void regs_set_return_value(struct pt_regs *regs,
118					 unsigned long val)
119{
120	regs->a0 = val;
121}
122
123extern int regs_query_register_offset(const char *name);
124extern unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
125					       unsigned int n);
126
127void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
128			   unsigned long frame_pointer);
129
130/**
131 * regs_get_register() - get register value from its offset
132 * @regs:	pt_regs from which register value is gotten
133 * @offset:	offset of the register.
134 *
135 * regs_get_register returns the value of a register whose offset from @regs.
136 * The @offset is the offset of the register in struct pt_regs.
137 * If @offset is bigger than MAX_REG_OFFSET, this returns 0.
138 */
139static inline unsigned long regs_get_register(struct pt_regs *regs,
140					      unsigned int offset)
141{
142	if (unlikely(offset > MAX_REG_OFFSET))
143		return 0;
144
145	return *(unsigned long *)((unsigned long)regs + offset);
146}
147
148/**
149 * regs_get_kernel_argument() - get Nth function argument in kernel
150 * @regs:       pt_regs of that context
151 * @n:          function argument number (start from 0)
152 *
153 * regs_get_argument() returns @n th argument of the function call.
154 *
155 * Note you can get the parameter correctly if the function has no
156 * more than eight arguments.
157 */
158static inline unsigned long regs_get_kernel_argument(struct pt_regs *regs,
159						unsigned int n)
160{
161	static const int nr_reg_arguments = 8;
162	static const unsigned int argument_offs[] = {
163		offsetof(struct pt_regs, a0),
164		offsetof(struct pt_regs, a1),
165		offsetof(struct pt_regs, a2),
166		offsetof(struct pt_regs, a3),
167		offsetof(struct pt_regs, a4),
168		offsetof(struct pt_regs, a5),
169		offsetof(struct pt_regs, a6),
170		offsetof(struct pt_regs, a7),
171	};
172
173	if (n < nr_reg_arguments)
174		return regs_get_register(regs, argument_offs[n]);
175	return 0;
176}
177
178static __always_inline bool regs_irqs_disabled(struct pt_regs *regs)
179{
180	return !(regs->status & SR_PIE);
181}
182
183#endif /* __ASSEMBLER__ */
184
185#endif /* _ASM_RISCV_PTRACE_H */