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, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 *
22 * $FreeBSD$
23 *
24 */
25 /*
26 * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
27 * Use is subject to license terms.
28 */
29
30 #include <sys/cdefs.h>
31 __KERNEL_RCSID(0, "$NetBSD: dtrace_subr.c,v 1.6 2023/04/17 06:57:02 skrll Exp $");
32
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/types.h>
36 #include <sys/kernel.h>
37 #include <sys/malloc.h>
38 #include <sys/kmem.h>
39 #include <sys/xcall.h>
40 #include <sys/cpu.h>
41 #include <sys/cpuvar.h>
42 #include <sys/dtrace_impl.h>
43 #include <sys/dtrace_bsd.h>
44 #include <machine/cpu.h>
45 #include <machine/frame.h>
46 #include <machine/vmparam.h>
47 #include <uvm/uvm_pglist.h>
48 #include <uvm/uvm_prot.h>
49 #include <uvm/uvm_pmap.h>
50
51 #define CURRENT_CPU cpu_index(curcpu())
52 #define OFFSET_MASK ((1 << OFFSET_SIZE) - 1)
53
54 extern dtrace_id_t dtrace_probeid_error;
55 extern int (*dtrace_invop_jump_addr)(struct trapframe *);
56 extern void dtrace_getnanotime(struct timespec *tsp);
57
58 int dtrace_invop(uintptr_t, struct trapframe *, uintptr_t);
59 void dtrace_invop_init(void);
60 void dtrace_invop_uninit(void);
61
62 void dtrace_gethrtime_init(void);
63
64 typedef struct dtrace_invop_hdlr {
65 int (*dtih_func)(uintptr_t, struct trapframe *, uintptr_t);
66 struct dtrace_invop_hdlr *dtih_next;
67 } dtrace_invop_hdlr_t;
68
69 dtrace_invop_hdlr_t *dtrace_invop_hdlr;
70
71 int
dtrace_invop(uintptr_t addr,struct trapframe * frame,uintptr_t r0)72 dtrace_invop(uintptr_t addr, struct trapframe *frame, uintptr_t r0)
73 {
74 dtrace_invop_hdlr_t *hdlr;
75 int rval;
76
77 for (hdlr = dtrace_invop_hdlr; hdlr != NULL; hdlr = hdlr->dtih_next)
78 if ((rval = hdlr->dtih_func(addr, frame, r0)) != 0)
79 return (rval);
80
81 return (0);
82 }
83
84
85 void
dtrace_invop_add(int (* func)(uintptr_t,struct trapframe *,uintptr_t))86 dtrace_invop_add(int (*func)(uintptr_t, struct trapframe *, uintptr_t))
87 {
88 dtrace_invop_hdlr_t *hdlr;
89
90 hdlr = kmem_alloc(sizeof(*hdlr), KM_SLEEP);
91 hdlr->dtih_func = func;
92 hdlr->dtih_next = dtrace_invop_hdlr;
93 dtrace_invop_hdlr = hdlr;
94 }
95
96 void
dtrace_invop_remove(int (* func)(uintptr_t,struct trapframe *,uintptr_t))97 dtrace_invop_remove(int (*func)(uintptr_t, struct trapframe *, uintptr_t))
98 {
99 dtrace_invop_hdlr_t *hdlr, *prev;
100
101 hdlr = dtrace_invop_hdlr;
102 prev = NULL;
103
104 for (;;) {
105 if (hdlr == NULL)
106 panic("attempt to remove non-existent invop handler");
107
108 if (hdlr->dtih_func == func)
109 break;
110
111 prev = hdlr;
112 hdlr = hdlr->dtih_next;
113 }
114
115 if (prev == NULL) {
116 ASSERT(dtrace_invop_hdlr == hdlr);
117 dtrace_invop_hdlr = hdlr->dtih_next;
118 } else {
119 ASSERT(dtrace_invop_hdlr != hdlr);
120 prev->dtih_next = hdlr->dtih_next;
121 }
122
123 kmem_free(hdlr, sizeof(*hdlr));
124 }
125
126 /*ARGSUSED*/
127 void
dtrace_toxic_ranges(void (* func)(uintptr_t base,uintptr_t limit))128 dtrace_toxic_ranges(void (*func)(uintptr_t base, uintptr_t limit))
129 {
130
131 (*func)(0, (uintptr_t)AARCH64_DIRECTMAP_START);
132 (*func)((uintptr_t)VM_KERNEL_IO_BASE, ~(uintptr_t)0);
133 }
134
135 static void
xcall_func(void * arg0,void * arg1)136 xcall_func(void *arg0, void *arg1)
137 {
138 dtrace_xcall_t func = arg0;
139
140 (*func)(arg1);
141 }
142
143 void
dtrace_xcall(processorid_t cpu,dtrace_xcall_t func,void * arg)144 dtrace_xcall(processorid_t cpu, dtrace_xcall_t func, void *arg)
145 {
146 uint64_t where;
147
148 if (cpu == DTRACE_CPUALL) {
149 where = xc_broadcast(0, xcall_func, func, arg);
150 } else {
151 struct cpu_info *ci = cpu_lookup(cpu);
152
153 KASSERT(ci != NULL);
154 where = xc_unicast(0, xcall_func, func, arg, ci);
155 }
156 xc_wait(where);
157 }
158
159 static void
dtrace_sync_func(void)160 dtrace_sync_func(void)
161 {
162
163 }
164
165 void
dtrace_sync(void)166 dtrace_sync(void)
167 {
168
169 dtrace_xcall(DTRACE_CPUALL, (dtrace_xcall_t)dtrace_sync_func, NULL);
170 }
171
172 /*
173 * DTrace needs a high resolution time function which can
174 * be called from a probe context and guaranteed not to have
175 * instrumented with probes itself.
176 *
177 * Returns nanoseconds since boot.
178 */
179 uint64_t
dtrace_gethrtime()180 dtrace_gethrtime()
181 {
182 struct timespec curtime;
183
184 nanouptime(&curtime);
185
186 return (curtime.tv_sec * 1000000000UL + curtime.tv_nsec);
187
188 }
189
190 void
dtrace_gethrtime_init(void)191 dtrace_gethrtime_init(void)
192 {
193 }
194
195 uint64_t
dtrace_gethrestime(void)196 dtrace_gethrestime(void)
197 {
198 struct timespec current_time;
199
200 dtrace_getnanotime(¤t_time);
201
202 return (current_time.tv_sec * 1000000000UL + current_time.tv_nsec);
203 }
204
205 /* Function to handle DTrace traps during probes. See arm64/arm64/trap.c */
206 int
dtrace_trap(struct trapframe * frame,u_int type)207 dtrace_trap(struct trapframe *frame, u_int type)
208 {
209 /*
210 * A trap can occur while DTrace executes a probe. Before
211 * executing the probe, DTrace blocks re-scheduling and sets
212 * a flag in its per-cpu flags to indicate that it doesn't
213 * want to fault. On returning from the probe, the no-fault
214 * flag is cleared and finally re-scheduling is enabled.
215 *
216 * Check if DTrace has enabled 'no-fault' mode:
217 *
218 */
219
220 if ((cpu_core[CURRENT_CPU].cpuc_dtrace_flags & CPU_DTRACE_NOFAULT) != 0) {
221 /*
222 * There are only a couple of trap types that are expected.
223 * All the rest will be handled in the usual way.
224 */
225 switch (type) {
226 case ESR_EC_DATA_ABT_EL1:
227 /* Flag a bad address. */
228 cpu_core[CURRENT_CPU].cpuc_dtrace_flags |= CPU_DTRACE_BADADDR;
229 cpu_core[CURRENT_CPU].cpuc_dtrace_illval = 0;
230
231 /*
232 * Offset the instruction pointer to the instruction
233 * following the one causing the fault.
234 */
235 frame->tf_pc += 4;
236 return (1);
237 default:
238 /* Handle all other traps in the usual way. */
239 break;
240 }
241 }
242
243 /* Handle the trap in the usual way. */
244 return (0);
245 }
246
247 void
dtrace_probe_error(dtrace_state_t * state,dtrace_epid_t epid,int which,int fault,int fltoffs,uintptr_t illval)248 dtrace_probe_error(dtrace_state_t *state, dtrace_epid_t epid, int which,
249 int fault, int fltoffs, uintptr_t illval)
250 {
251
252 dtrace_probe(dtrace_probeid_error, (uint64_t)(uintptr_t)state,
253 (uintptr_t)epid,
254 (uintptr_t)which, (uintptr_t)fault, (uintptr_t)fltoffs);
255 }
256
257 static int
dtrace_invop_start(struct trapframe * frame)258 dtrace_invop_start(struct trapframe *frame)
259 {
260 int data, invop, reg, update_sp;
261 register_t arg1, arg2;
262 register_t *sp;
263 int offs;
264 int tmp;
265 int i;
266
267 invop = dtrace_invop(frame->tf_pc, frame, frame->tf_regs.r_reg[0]);
268
269 tmp = (invop & LDP_STP_MASK);
270 if (tmp == STP_64 || tmp == LDP_64) {
271 sp = (register_t *)frame->tf_sp;
272 data = invop;
273 arg1 = (data >> ARG1_SHIFT) & ARG1_MASK;
274 arg2 = (data >> ARG2_SHIFT) & ARG2_MASK;
275
276 offs = (data >> OFFSET_SHIFT) & OFFSET_MASK;
277
278 switch (tmp) {
279 case STP_64:
280 if (offs >> (OFFSET_SIZE - 1))
281 sp -= (~offs & OFFSET_MASK) + 1;
282 else
283 sp += (offs);
284 *(sp + 0) = frame->tf_regs.r_reg[arg1];
285 *(sp + 1) = frame->tf_regs.r_reg[arg2];
286 break;
287 case LDP_64:
288 frame->tf_regs.r_reg[arg1] = *(sp + 0);
289 frame->tf_regs.r_reg[arg2] = *(sp + 1);
290 if (offs >> (OFFSET_SIZE - 1))
291 sp -= (~offs & OFFSET_MASK) + 1;
292 else
293 sp += (offs);
294 break;
295 default:
296 break;
297 }
298
299 /* Update the stack pointer and program counter to continue */
300 frame->tf_sp = (register_t)sp;
301 frame->tf_pc += INSN_SIZE;
302 return (0);
303 }
304
305 if ((invop & B_MASK) == B_INSTR) {
306 data = (invop & B_DATA_MASK);
307 /* The data is the number of 4-byte words to change the pc */
308 data *= 4;
309 frame->tf_pc += data;
310 return (0);
311 }
312
313 if (invop == RET_INSTR) {
314 frame->tf_pc = frame->tf_lr;
315 return (0);
316 }
317
318 return (-1);
319 }
320
321 void
dtrace_invop_init(void)322 dtrace_invop_init(void)
323 {
324
325 dtrace_invop_jump_addr = dtrace_invop_start;
326 }
327
328 void
dtrace_invop_uninit(void)329 dtrace_invop_uninit(void)
330 {
331
332 dtrace_invop_jump_addr = 0;
333 }
334