1/*
2 * Copyright (C) 2014 Altera Corporation
3 * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
4 *
5 * This file is subject to the terms and conditions of the GNU General
6 * Public License. See the file COPYING in the main directory of this
7 * archive for more details.
8 */
9
10#include <linux/elf.h>
11#include <linux/errno.h>
12#include <linux/kernel.h>
13#include <linux/mm.h>
14#include <linux/ptrace.h>
15#include <linux/regset.h>
16#include <linux/sched.h>
17#include <linux/sched/task_stack.h>
18#include <linux/uaccess.h>
19#include <linux/user.h>
20
21static int genregs_get(struct task_struct *target,
22 const struct user_regset *regset,
23 struct membuf to)
24{
25 const struct pt_regs *regs = task_pt_regs(target);
26 const struct switch_stack *sw = (struct switch_stack *)regs - 1;
27
28 membuf_zero(s: &to, size: 4); // R0
29 membuf_write(s: &to, v: &regs->r1, size: 7 * 4); // R1..R7
30 membuf_write(s: &to, v: &regs->r8, size: 8 * 4); // R8..R15
31 membuf_write(s: &to, v: sw, size: 8 * 4); // R16..R23
32 membuf_zero(s: &to, size: 2 * 4); /* et and bt */
33 membuf_store(&to, regs->gp);
34 membuf_store(&to, regs->sp);
35 membuf_store(&to, regs->fp);
36 membuf_store(&to, regs->ea);
37 membuf_zero(s: &to, size: 4); // PTR_BA
38 membuf_store(&to, regs->ra);
39 membuf_store(&to, regs->ea); /* use ea for PC */
40 return membuf_zero(&to, (NUM_PTRACE_REG - PTR_PC) * 4);
41}
42
43/*
44 * Set the thread state from a regset passed in via ptrace
45 */
46static int genregs_set(struct task_struct *target,
47 const struct user_regset *regset,
48 unsigned int pos, unsigned int count,
49 const void *kbuf, const void __user *ubuf)
50{
51 struct pt_regs *regs = task_pt_regs(target);
52 const struct switch_stack *sw = (struct switch_stack *)regs - 1;
53 int ret = 0;
54
55#define REG_IGNORE_RANGE(START, END) \
56 if (!ret) \
57 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, \
58 START * 4, (END * 4) + 4);
59
60#define REG_IN_ONE(PTR, LOC) \
61 if (!ret) \
62 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
63 (void *)(PTR), LOC * 4, (LOC * 4) + 4);
64
65#define REG_IN_RANGE(PTR, START, END) \
66 if (!ret) \
67 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
68 (void *)(PTR), START * 4, (END * 4) + 4);
69
70 REG_IGNORE_RANGE(PTR_R0, PTR_R0);
71 REG_IN_RANGE(&regs->r1, PTR_R1, PTR_R7);
72 REG_IN_RANGE(&regs->r8, PTR_R8, PTR_R15);
73 REG_IN_RANGE(sw, PTR_R16, PTR_R23);
74 REG_IGNORE_RANGE(PTR_R24, PTR_R25); /* et and bt */
75 REG_IN_ONE(&regs->gp, PTR_GP);
76 REG_IN_ONE(&regs->sp, PTR_SP);
77 REG_IN_ONE(&regs->fp, PTR_FP);
78 REG_IN_ONE(&regs->ea, PTR_EA);
79 REG_IGNORE_RANGE(PTR_BA, PTR_BA);
80 REG_IN_ONE(&regs->ra, PTR_RA);
81 REG_IN_ONE(&regs->ea, PTR_PC); /* use ea for PC */
82 if (!ret)
83 user_regset_copyin_ignore(pos: &pos, count: &count, kbuf: &kbuf, ubuf: &ubuf,
84 start_pos: PTR_STATUS * 4, end_pos: -1);
85
86 return ret;
87}
88
89/*
90 * Define the register sets available on Nios2 under Linux
91 */
92enum nios2_regset {
93 REGSET_GENERAL,
94};
95
96static const struct user_regset nios2_regsets[] = {
97 [REGSET_GENERAL] = {
98 .core_note_type = NT_PRSTATUS,
99 .n = NUM_PTRACE_REG,
100 .size = sizeof(unsigned long),
101 .align = sizeof(unsigned long),
102 .regset_get = genregs_get,
103 .set = genregs_set,
104 }
105};
106
107static const struct user_regset_view nios2_user_view = {
108 .name = "nios2",
109 .e_machine = ELF_ARCH,
110 .ei_osabi = ELF_OSABI,
111 .regsets = nios2_regsets,
112 .n = ARRAY_SIZE(nios2_regsets)
113};
114
115const struct user_regset_view *task_user_regset_view(struct task_struct *task)
116{
117 return &nios2_user_view;
118}
119
120void ptrace_disable(struct task_struct *child)
121{
122
123}
124
125long arch_ptrace(struct task_struct *child, long request, unsigned long addr,
126 unsigned long data)
127{
128 return ptrace_request(child, request, addr, data);
129}
130
131asmlinkage int do_syscall_trace_enter(void)
132{
133 int ret = 0;
134
135 if (test_thread_flag(TIF_SYSCALL_TRACE))
136 ret = ptrace_report_syscall_entry(task_pt_regs(current));
137
138 return ret;
139}
140
141asmlinkage void do_syscall_trace_exit(void)
142{
143 if (test_thread_flag(TIF_SYSCALL_TRACE))
144 ptrace_report_syscall_exit(task_pt_regs(current), step: 0);
145}
146

source code of linux/arch/nios2/kernel/ptrace.c