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/thread.h>
28 #include <mach/thread_status.h>
29 #include <mach/vm_param.h>
30
31 #include <sys/dtrace.h>
32 #include <sys/dtrace_impl.h>
33
34 #include <sys/dtrace_glue.h>
35
36 #include <sys/sdt_impl.h>
37
38 extern sdt_probe_t **sdt_probetab;
39
40 int
sdt_invop(__unused uintptr_t addr,__unused uintptr_t * stack,__unused uintptr_t eax)41 sdt_invop(__unused uintptr_t addr, __unused uintptr_t *stack, __unused uintptr_t eax)
42 {
43 #pragma unused(eax)
44 sdt_probe_t *sdt = sdt_probetab[SDT_ADDR2NDX(addr)];
45
46 for (; sdt != NULL; sdt = sdt->sdp_hashnext) {
47 if ((uintptr_t) sdt->sdp_patchpoint == addr) {
48 struct arm_saved_state* regs = (struct arm_saved_state*) stack;
49 uintptr_t stack4 = *((uintptr_t*) regs->sp);
50
51 dtrace_probe(sdt->sdp_id, regs->r[0], regs->r[1], regs->r[2], regs->r[3], stack4);
52
53 return DTRACE_INVOP_NOP;
54 }
55 }
56
57 return 0;
58 }
59
60 struct frame {
61 struct frame *backchain;
62 uintptr_t retaddr;
63 };
64
65 /*ARGSUSED*/
66 uint64_t
sdt_getarg(void * arg,dtrace_id_t id,void * parg,int argno,int aframes)67 sdt_getarg(void *arg, dtrace_id_t id, void *parg, int argno, int aframes)
68 {
69 #pragma unused(arg,id,parg) /* __APPLE__ */
70 uint64_t val = 0;
71 struct frame *fp = (struct frame *)__builtin_frame_address(0);
72 uintptr_t *stack;
73 uintptr_t pc;
74 int i;
75
76 /*
77 * On ARM, up to four args are passed via registers; r0,r1,r2,r3
78 * So coming into this function, arg >= 4 should be on the stack.
79 * e.g. arg==5 refers to the 6th arg passed to the probed function.
80 */
81 int inreg = 4;
82
83 for (i = 1; i <= aframes; i++) {
84 fp = fp->backchain;
85 pc = fp->retaddr;
86
87 if (dtrace_invop_callsite_pre != NULL
88 && pc > (uintptr_t)dtrace_invop_callsite_pre
89 && pc <= (uintptr_t)dtrace_invop_callsite_post) {
90 /*
91 * When we pass through the invalid op handler,
92 * we expect to find the save area structure,
93 * pushed on the stack where we took the trap.
94 * If the argument we seek is passed in a register, then
95 * we can load it directly from this saved area.
96 * If the argument we seek is passed on the stack, then
97 * we increment the frame pointer further, to find the
98 * pushed args
99 */
100
101 /* fp points to the dtrace_invop activation */
102 fp = fp->backchain; /* to the fbt_perfCallback activation */
103 fp = fp->backchain; /* to the sleh_undef activation */
104
105 #if __BIGGEST_ALIGNMENT__ > 4
106 /**
107 * rdar://problem/24228656: On armv7k, the stack is realigned in sleh_undef2 to
108 * be 16-bytes aligned and the old value is pushed to
109 * the stack, so we retrieve it from here
110 */
111 arm_saved_state_t *saved_state = (arm_saved_state_t *)(uintptr_t*)*((uintptr_t *)&fp[1]);
112 #else
113 arm_saved_state_t *saved_state = (arm_saved_state_t *)((uintptr_t *)&fp[1]);
114 #endif
115 if (argno <= inreg) {
116 /* For clarity only... should not get here */
117 stack = (uintptr_t *)&saved_state->r[0];
118 } else {
119 fp = (struct frame *)(saved_state->sp);
120 stack = (uintptr_t *)&fp[0]; /* Find marshalled arguments */
121 argno -= inreg;
122 }
123 goto load;
124 }
125 }
126
127 /*
128 * We know that we did not come through a trap to get into
129 * dtrace_probe() -- We arrive here when the provider has
130 * called dtrace_probe() directly.
131 * The probe ID is the first argument to dtrace_probe().
132 * We must advance beyond that to get the argX.
133 */
134 argno++; /* Advance past probeID */
135
136 if (argno <= inreg) {
137 /*
138 * This shouldn't happen. If the argument is passed in a
139 * register then it should have been, well, passed in a
140 * register...
141 */
142 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
143 return 0;
144 }
145
146 argno -= (inreg + 1);
147 stack = (uintptr_t *)&fp[1]; /* Find marshalled arguments */
148
149 load:
150 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
151 /* dtrace_probe arguments arg0 .. arg4 are 64bits wide */
152 val = (uint64_t)(*(((uintptr_t *)stack) + argno));
153 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
154 return val;
155 }
156