aboutsummaryrefslogtreecommitdiffstats
path: root/arch/tile/kernel/ptrace.c
blob: 468054928e7d4f62a517d88a2cc4100c452dca5a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
/*
 * Copyright 2010 Tilera Corporation. All Rights Reserved.
 *
 *   This program is free software; you can redistribute it and/or
 *   modify it under the terms of the GNU General Public License
 *   as published by the Free Software Foundation, version 2.
 *
 *   This program is distributed in the hope that it will be useful, but
 *   WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 *   NON INFRINGEMENT.  See the GNU General Public License for
 *   more details.
 *
 * Copied from i386: Ross Biro 1/23/92
 */

#include <linux/kernel.h>
#include <linux/ptrace.h>
#include <linux/kprobes.h>
#include <linux/compat.h>
#include <linux/uaccess.h>

void user_enable_single_step(struct task_struct *child)
{
	set_tsk_thread_flag(child, TIF_SINGLESTEP);
}

void user_disable_single_step(struct task_struct *child)
{
	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
}

/*
 * This routine will put a word on the process's privileged stack.
 */
static void putreg(struct task_struct *task,
		   unsigned long addr, unsigned long value)
{
	unsigned int regno = addr / sizeof(unsigned long);
	struct pt_regs *childregs = task_pt_regs(task);
	childregs->regs[regno] = value;
	childregs->flags |= PT_FLAGS_RESTORE_REGS;
}

static unsigned long getreg(struct task_struct *task, unsigned long addr)
{
	unsigned int regno = addr / sizeof(unsigned long);
	struct pt_regs *childregs = task_pt_regs(task);
	return childregs->regs[regno];
}

/*
 * Called by kernel/ptrace.c when detaching..
 */
void ptrace_disable(struct task_struct *child)
{
	clear_tsk_thread_flag(child, TIF_SINGLESTEP);

	/*
	 * These two are currently unused, but will be set by arch_ptrace()
	 * and used in the syscall assembly when we do support them.
	 */
	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
}

long arch_ptrace(struct task_struct *child, long request, long addr, long data)
{
	unsigned long __user *datap;
	unsigned long tmp;
	int i;
	long ret = -EIO;

#ifdef CONFIG_COMPAT
	if (task_thread_info(current)->status & TS_COMPAT)
		data = (u32)data;
	if (task_thread_info(child)->status & TS_COMPAT)
		addr = (u32)addr;
#endif
	datap = (unsigned long __user *)data;

	switch (request) {

	case PTRACE_PEEKUSR:  /* Read register from pt_regs. */
		if (addr & (sizeof(data)-1))
			break;
		if (addr < 0 || addr >= PTREGS_SIZE)
			break;
		tmp = getreg(child, addr);   /* Read register */
		ret = put_user(tmp, datap);
		break;

	case PTRACE_POKEUSR:  /* Write register in pt_regs. */
		if (addr & (sizeof(data)-1))
			break;
		if (addr < 0 || addr >= PTREGS_SIZE)
			break;
		putreg(child, addr, data);   /* Write register */
		break;

	case PTRACE_GETREGS:  /* Get all registers from the child. */
		if (!access_ok(VERIFY_WRITE, datap, PTREGS_SIZE))
			break;
		for (i = 0; i < PTREGS_SIZE; i += sizeof(long)) {
			ret = __put_user(getreg(child, i), datap);
			if (ret != 0)
				break;
			datap++;
		}
		break;

	case PTRACE_SETREGS:  /* Set all registers in the child. */
		if (!access_ok(VERIFY_READ, datap, PTREGS_SIZE))
			break;
		for (i = 0; i < PTREGS_SIZE; i += sizeof(long)) {
			ret = __get_user(tmp, datap);
			if (ret != 0)
				break;
			putreg(child, i, tmp);
			datap++;
		}
		break;

	case PTRACE_GETFPREGS:  /* Get the child FPU state. */
	case PTRACE_SETFPREGS:  /* Set the child FPU state. */
		break;

	case PTRACE_SETOPTIONS:
		/* Support TILE-specific ptrace options. */
		child->ptrace &= ~PT_TRACE_MASK_TILE;
		tmp = data & PTRACE_O_MASK_TILE;
		data &= ~PTRACE_O_MASK_TILE;
		ret = ptrace_request(child, request, addr, data);
		if (tmp & PTRACE_O_TRACEMIGRATE)
			child->ptrace |= PT_TRACE_MIGRATE;
		break;

	default:
#ifdef CONFIG_COMPAT
		if (task_thread_info(current)->status & TS_COMPAT) {
			ret = compat_ptrace_request(child, request,
						    addr, data);
			break;
		}
#endif
		ret = ptrace_request(child, request, addr, data);
		break;
	}

	return ret;
}

#ifdef CONFIG_COMPAT
/* Not used; we handle compat issues in arch_ptrace() directly. */
long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
			       compat_ulong_t addr, compat_ulong_t data)
{
	BUG();
}
#endif

void do_syscall_trace(void)
{
	if (!test_thread_flag(TIF_SYSCALL_TRACE))
		return;

	if (!(current->ptrace & PT_PTRACED))
		return;

	/*
	 * The 0x80 provides a way for the tracing parent to distinguish
	 * between a syscall stop and SIGTRAP delivery
	 */
	ptrace_notify(SIGTRAP|((current->ptrace & PT_TRACESYSGOOD) ? 0x80 : 0));

	/*
	 * this isn't the same as continuing with a signal, but it will do
	 * for normal use.  strace only continues with a signal if the
	 * stopping signal is not SIGTRAP.  -brl
	 */
	if (current->exit_code) {
		send_sig(current->exit_code, current, 1);
		current->exit_code = 0;
	}
}

void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code)
{
	struct siginfo info;

	memset(&info, 0, sizeof(info));
	info.si_signo = SIGTRAP;
	info.si_code  = TRAP_BRKPT;
	info.si_addr  = (void __user *) regs->pc;

	/* Send us the fakey SIGTRAP */
	force_sig_info(SIGTRAP, &info, tsk);
}

/* Handle synthetic interrupt delivered only by the simulator. */
void __kprobes do_breakpoint(struct pt_regs* regs, int fault_num)
{
	send_sigtrap(current, regs, fault_num);
}