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/tracehook.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		       unsigned int pos, unsigned int count,
24		       void *kbuf, void __user *ubuf)
25{
26	const struct pt_regs *regs = task_pt_regs(target);
27	const struct switch_stack *sw = (struct switch_stack *)regs - 1;
28	int ret = 0;
29
30#define REG_O_ZERO_RANGE(START, END)		\
31	if (!ret)					\
32		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, \
33			START * 4, (END * 4) + 4);
34
35#define REG_O_ONE(PTR, LOC)	\
36	if (!ret)			\
37		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, PTR, \
38			LOC * 4, (LOC * 4) + 4);
39
40#define REG_O_RANGE(PTR, START, END)	\
41	if (!ret)				\
42		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, PTR, \
43			START * 4, (END * 4) + 4);
44
45	REG_O_ZERO_RANGE(PTR_R0, PTR_R0);
46	REG_O_RANGE(&regs->r1, PTR_R1, PTR_R7);
47	REG_O_RANGE(&regs->r8, PTR_R8, PTR_R15);
48	REG_O_RANGE(sw, PTR_R16, PTR_R23);
49	REG_O_ZERO_RANGE(PTR_R24, PTR_R25); /* et and bt */
50	REG_O_ONE(&regs->gp, PTR_GP);
51	REG_O_ONE(&regs->sp, PTR_SP);
52	REG_O_ONE(&regs->fp, PTR_FP);
53	REG_O_ONE(&regs->ea, PTR_EA);
54	REG_O_ZERO_RANGE(PTR_BA, PTR_BA);
55	REG_O_ONE(&regs->ra, PTR_RA);
56	REG_O_ONE(&regs->ea, PTR_PC); /* use ea for PC */
57	if (!ret)
58		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
59					 PTR_STATUS * 4, -1);
60
61	return ret;
62}
63
64/*
65 * Set the thread state from a regset passed in via ptrace
66 */
67static int genregs_set(struct task_struct *target,
68		       const struct user_regset *regset,
69		       unsigned int pos, unsigned int count,
70		       const void *kbuf, const void __user *ubuf)
71{
72	struct pt_regs *regs = task_pt_regs(target);
73	const struct switch_stack *sw = (struct switch_stack *)regs - 1;
74	int ret = 0;
75
76#define REG_IGNORE_RANGE(START, END)		\
77	if (!ret)					\
78		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, \
79			START * 4, (END * 4) + 4);
80
81#define REG_IN_ONE(PTR, LOC)	\
82	if (!ret)			\
83		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
84			(void *)(PTR), LOC * 4, (LOC * 4) + 4);
85
86#define REG_IN_RANGE(PTR, START, END)	\
87	if (!ret)				\
88		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
89			(void *)(PTR), START * 4, (END * 4) + 4);
90
91	REG_IGNORE_RANGE(PTR_R0, PTR_R0);
92	REG_IN_RANGE(&regs->r1, PTR_R1, PTR_R7);
93	REG_IN_RANGE(&regs->r8, PTR_R8, PTR_R15);
94	REG_IN_RANGE(sw, PTR_R16, PTR_R23);
95	REG_IGNORE_RANGE(PTR_R24, PTR_R25); /* et and bt */
96	REG_IN_ONE(&regs->gp, PTR_GP);
97	REG_IN_ONE(&regs->sp, PTR_SP);
98	REG_IN_ONE(&regs->fp, PTR_FP);
99	REG_IN_ONE(&regs->ea, PTR_EA);
100	REG_IGNORE_RANGE(PTR_BA, PTR_BA);
101	REG_IN_ONE(&regs->ra, PTR_RA);
102	REG_IN_ONE(&regs->ea, PTR_PC); /* use ea for PC */
103	if (!ret)
104		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
105					 PTR_STATUS * 4, -1);
106
107	return ret;
108}
109
110/*
111 * Define the register sets available on Nios2 under Linux
112 */
113enum nios2_regset {
114	REGSET_GENERAL,
115};
116
117static const struct user_regset nios2_regsets[] = {
118	[REGSET_GENERAL] = {
119		.core_note_type = NT_PRSTATUS,
120		.n = NUM_PTRACE_REG,
121		.size = sizeof(unsigned long),
122		.align = sizeof(unsigned long),
123		.get = genregs_get,
124		.set = genregs_set,
125	}
126};
127
128static const struct user_regset_view nios2_user_view = {
129	.name = "nios2",
130	.e_machine = ELF_ARCH,
131	.ei_osabi = ELF_OSABI,
132	.regsets = nios2_regsets,
133	.n = ARRAY_SIZE(nios2_regsets)
134};
135
136const struct user_regset_view *task_user_regset_view(struct task_struct *task)
137{
138	return &nios2_user_view;
139}
140
141void ptrace_disable(struct task_struct *child)
142{
143
144}
145
146long arch_ptrace(struct task_struct *child, long request, unsigned long addr,
147		 unsigned long data)
148{
149	return ptrace_request(child, request, addr, data);
150}
151
152asmlinkage int do_syscall_trace_enter(void)
153{
154	int ret = 0;
155
156	if (test_thread_flag(TIF_SYSCALL_TRACE))
157		ret = tracehook_report_syscall_entry(task_pt_regs(current));
158
159	return ret;
160}
161
162asmlinkage void do_syscall_trace_exit(void)
163{
164	if (test_thread_flag(TIF_SYSCALL_TRACE))
165		tracehook_report_syscall_exit(task_pt_regs(current), 0);
166}
167