1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2007-2008 John Birrell <jb@FreeBSD.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <sys/cdefs.h>
30#include "opt_kdb.h"
31
32#include <sys/param.h>
33#include <sys/systm.h>
34#include <sys/eventhandler.h>
35#include <sys/kdb.h>
36#include <sys/kernel.h>
37#include <sys/malloc.h>
38#include <sys/proc.h>
39#include <sys/dtrace_bsd.h>
40#include <sys/sysctl.h>
41#include <sys/sysent.h>
42
43#define KDTRACE_PROC_SIZE	64
44#define	KDTRACE_THREAD_SIZE	256
45
46FEATURE(kdtrace_hooks,
47    "Kernel DTrace hooks which are required to load DTrace kernel modules");
48
49static MALLOC_DEFINE(M_KDTRACE, "kdtrace", "DTrace hooks");
50
51/* Hooks used in the machine-dependent trap handlers. */
52dtrace_trap_func_t		dtrace_trap_func;
53dtrace_doubletrap_func_t	dtrace_doubletrap_func;
54dtrace_pid_probe_ptr_t		dtrace_pid_probe_ptr;
55dtrace_return_probe_ptr_t	dtrace_return_probe_ptr;
56
57bool __read_frequently		systrace_enabled;
58systrace_probe_func_t 		systrace_probe_func;
59
60/* Return the DTrace process data size compiled in the kernel hooks. */
61size_t
62kdtrace_proc_size(void)
63{
64
65	return (KDTRACE_PROC_SIZE);
66}
67
68void
69kdtrace_proc_ctor(struct proc *p)
70{
71
72	p->p_dtrace = malloc(KDTRACE_PROC_SIZE, M_KDTRACE, M_WAITOK|M_ZERO);
73}
74
75void
76kdtrace_proc_dtor(struct proc *p)
77{
78
79	free(p->p_dtrace, M_KDTRACE);
80	p->p_dtrace = NULL;
81}
82
83/* Return the DTrace thread data size compiled in the kernel hooks. */
84size_t
85kdtrace_thread_size(void)
86{
87
88	return (KDTRACE_THREAD_SIZE);
89}
90
91void
92kdtrace_thread_ctor(struct thread *td)
93{
94
95	td->td_dtrace = malloc(KDTRACE_THREAD_SIZE, M_KDTRACE, M_WAITOK|M_ZERO);
96}
97
98void
99kdtrace_thread_dtor(struct thread *td)
100{
101
102	free(td->td_dtrace, M_KDTRACE);
103	td->td_dtrace = NULL;
104}
105