1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27/*
28 * #pragma ident	"@(#)dtrace_subr.c	1.8	07/06/05 SMI"
29 */
30
31#include <stdarg.h>
32#include <string.h>
33#include <sys/malloc.h>
34#include <sys/time.h>
35#include <sys/dtrace.h>
36#include <sys/dtrace_impl.h>
37#include <kern/debug.h>
38
39#if defined(__APPLE__)
40/* Solaris proc_t is the struct. Darwin's proc_t is a pointer to it. */
41#define proc_t struct proc /* Steer clear of the Darwin typedef for proc_t */
42#endif
43
44/* Copied from an arch specific dtrace_subr.c. */
45int (*dtrace_fasttrap_probe_ptr)(struct regs *);
46
47/*
48 * Following DTrace hooks are taken from Solaris' dtrace_subr.c
49 * They're assigned in dtrace.c but Darwin never calls them.
50 */
51void (*dtrace_cpu_init)(processorid_t);
52#if !defined(__APPLE__)
53void (*dtrace_modload)(struct modctl *);
54void (*dtrace_modunload)(struct modctl *);
55#else
56int (*dtrace_modload)(struct kmod_info *, uint32_t);
57int (*dtrace_modunload)(struct kmod_info *);
58void (*dtrace_helpers_cleanup)(proc_t *);
59#endif  /*__APPLE__*/
60void (*dtrace_helpers_fork)(proc_t *, proc_t *);
61void (*dtrace_cpustart_init)(void);
62void (*dtrace_cpustart_fini)(void);
63
64void (*dtrace_debugger_init)(void);
65void (*dtrace_debugger_fini)(void);
66
67dtrace_vtime_state_t dtrace_vtime_active = 0;
68dtrace_cacheid_t dtrace_predcache_id = DTRACE_CACHEIDNONE + 1;
69
70void (*dtrace_fasttrap_fork_ptr)(proc_t *, proc_t *);
71void (*dtrace_fasttrap_exec_ptr)(proc_t *);
72void (*dtrace_fasttrap_exit_ptr)(proc_t *);
73
74/*
75 * This function is called by cfork() in the event that it appears that
76 * there may be dtrace tracepoints active in the parent process's address
77 * space. This first confirms the existence of dtrace tracepoints in the
78 * parent process and calls into the fasttrap module to remove the
79 * corresponding tracepoints from the child. By knowing that there are
80 * existing tracepoints, and ensuring they can't be removed, we can rely
81 * on the fasttrap module remaining loaded.
82 */
83void
84dtrace_fasttrap_fork(proc_t *p, proc_t *cp)
85{
86#if !defined(__APPLE__)
87	ASSERT(p->p_proc_flag & P_PR_LOCK);
88	ASSERT(p->p_dtrace_count > 0);
89#endif /* __APPLE__ */
90
91	if (dtrace_fasttrap_fork_ptr) {
92		(*dtrace_fasttrap_fork_ptr)(p, cp);
93	}
94}
95
96typedef struct dtrace_invop_hdlr {
97	int (*dtih_func)(uintptr_t, uintptr_t *, uintptr_t);
98	struct dtrace_invop_hdlr *dtih_next;
99} dtrace_invop_hdlr_t;
100
101dtrace_invop_hdlr_t *dtrace_invop_hdlr;
102
103int
104dtrace_invop(uintptr_t, uintptr_t *, uintptr_t);
105
106int
107dtrace_invop(uintptr_t addr, uintptr_t *stack, uintptr_t eax)
108{
109	dtrace_invop_hdlr_t *hdlr;
110	int rval;
111
112	for (hdlr = dtrace_invop_hdlr; hdlr != NULL; hdlr = hdlr->dtih_next) {
113		if ((rval = hdlr->dtih_func(addr, stack, eax)) != 0)
114			return (rval);
115	}
116
117	return (0);
118}
119
120void
121dtrace_invop_add(int (*func)(uintptr_t, uintptr_t *, uintptr_t))
122{
123	dtrace_invop_hdlr_t *hdlr;
124
125	hdlr = kmem_alloc(sizeof (dtrace_invop_hdlr_t), KM_SLEEP);
126	hdlr->dtih_func = func;
127	hdlr->dtih_next = dtrace_invop_hdlr;
128	dtrace_invop_hdlr = hdlr;
129}
130
131void
132dtrace_invop_remove(int (*func)(uintptr_t, uintptr_t *, uintptr_t))
133{
134	dtrace_invop_hdlr_t *hdlr = dtrace_invop_hdlr, *prev = NULL;
135
136	for (;;) {
137		if (hdlr == NULL)
138			panic("attempt to remove non-existent invop handler");
139
140		if (hdlr->dtih_func == func)
141			break;
142
143		prev = hdlr;
144		hdlr = hdlr->dtih_next;
145	}
146
147	if (prev == NULL) {
148		ASSERT(dtrace_invop_hdlr == hdlr);
149		dtrace_invop_hdlr = hdlr->dtih_next;
150	} else {
151		ASSERT(dtrace_invop_hdlr != hdlr);
152		prev->dtih_next = hdlr->dtih_next;
153	}
154
155	kmem_free(hdlr, sizeof (dtrace_invop_hdlr_t));
156}
157
158