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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 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26/* #pragma ident "@(#)sdt.c 1.6 06/03/24 SMI" */
27
28#ifdef KERNEL
29#ifndef _KERNEL
30#define _KERNEL /* Solaris vs. Darwin */
31#endif
32#endif
33
34#include <kern/cpu_data.h>
35#include <kern/debug.h>
36#include <kern/thread.h>
37#include <mach/thread_status.h>
38#include <mach/vm_param.h>
39
40#include <sys/dtrace.h>
41#include <sys/dtrace_impl.h>
42
43#include <sys/dtrace_glue.h>
44
45#include <sys/sdt_impl.h>
46
47extern sdt_probe_t **sdt_probetab;
48
49int
50sdt_invop(__unused uintptr_t addr, __unused uintptr_t *stack, __unused uintptr_t eax)
51{
52#pragma unused(eax)
53 sdt_probe_t *sdt = sdt_probetab[SDT_ADDR2NDX(addr)];
54
55 for (; sdt != NULL; sdt = sdt->sdp_hashnext) {
56 if ((uintptr_t) sdt->sdp_patchpoint == addr) {
57 struct arm_saved_state* regs = (struct arm_saved_state*) stack;
58
59 dtrace_probe(sdt->sdp_id, get_saved_state_reg(regs, 0), get_saved_state_reg(regs, 1),
60 get_saved_state_reg(regs, 2), get_saved_state_reg(regs, 3),get_saved_state_reg(regs, 4));
61
62 return (DTRACE_INVOP_NOP);
63 }
64 }
65
66 return (0);
67}
68
69struct frame {
70 struct frame *backchain;
71 uintptr_t retaddr;
72};
73
74/*ARGSUSED*/
75uint64_t
76sdt_getarg(void *arg, dtrace_id_t id, void *parg, int argno, int aframes)
77{
78
79#pragma unused(arg,id,parg) /* __APPLE__ */
80
81 uint64_t val = 0;
82 struct frame *fp = (struct frame *)__builtin_frame_address(0);
83 uintptr_t *stack;
84 uintptr_t pc;
85 int i;
86
87 /*
88 * A total of eight arguments are passed via registers; any argument
89 * with an index of 7 or lower is therefore in a register.
90 */
91
92 int inreg = 7;
93
94 for (i = 1; i <= aframes; i++) {
95 fp = fp->backchain;
96 pc = fp->retaddr;
97
98 if (dtrace_invop_callsite_pre != NULL
99 && pc > (uintptr_t)dtrace_invop_callsite_pre
100 && pc <= (uintptr_t)dtrace_invop_callsite_post) {
101
102 /*
103 * When we pass through the invalid op handler,
104 * we expect to find the save area structure,
105 * pushed on the stack where we took the trap.
106 * If the argument we seek is passed in a register, then
107 * we can load it directly from this saved area.
108 * If the argument we seek is passed on the stack, then
109 * we increment the frame pointer further, to find the
110 * pushed args
111 */
112
113 /* fp points to the dtrace_invop activation */
114 fp = fp->backchain; /* fbt_perfCallback */
115 fp = fp->backchain; /* sleh_synchronous */
116 fp = fp->backchain; /* fleh_synchronous */
117
118 arm_saved_state_t *tagged_regs = (arm_saved_state_t *)((uintptr_t *)&fp[1]);
119 arm_saved_state64_t *saved_state = saved_state64(tagged_regs);
120
121 if (argno <= inreg) {
122 /* The argument will be in a register */
123 stack = (uintptr_t *)&saved_state->x[0];
124 } else {
125 /* The argument will be found on the stack */
126 fp = (struct frame *)(saved_state->sp);
127 stack = (uintptr_t *)&fp[0]; /* Find marshalled arguments */
128 argno -= (inreg + 1);
129 }
130 goto load;
131 }
132 }
133
134 /*
135 * We know that we did not come through a trap to get into
136 * dtrace_probe() -- We arrive here when the provider has
137 * called dtrace_probe() directly.
138 * The probe ID is the first argument to dtrace_probe().
139 * We must advance beyond that to get the argX.
140 */
141 argno++; /* Advance past probeID */
142
143 if (argno <= inreg) {
144 /*
145 * This shouldn't happen. If the argument is passed in a
146 * register then it should have been, well, passed in a
147 * register...
148 */
149 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
150 return (0);
151 }
152
153 argno -= (inreg + 1);
154 stack = (uintptr_t *)&fp[1]; /* Find marshalled arguments */
155
156load:
157 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
158 /* dtrace_probe arguments arg0 .. arg4 are 64bits wide */
159 val = (uint64_t)(*(((uintptr_t *)stack) + argno));
160 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
161 return (val);
162}