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