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 2007 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <stddef.h>
27 #include <stdlib.h>
28 #include <strings.h>
29 #include <errno.h>
30 #include <unistd.h>
31 #include <assert.h>
32 #include <alloca.h>
33 
34 #include <dt_impl.h>
35 #include <dt_program.h>
36 
37 static const char _dt_errprog[] =
38 "dtrace:::ERROR"
39 "{"
40 "	trace(arg1);"
41 "	trace(arg2);"
42 "	trace(arg3);"
43 "	trace(arg4);"
44 "	trace(arg5);"
45 "}";
46 
47 int
dtrace_handle_err(dtrace_hdl_t * dtp,dtrace_handle_err_f * hdlr,void * arg)48 dtrace_handle_err(dtrace_hdl_t *dtp, dtrace_handle_err_f *hdlr, void *arg)
49 {
50 	dtrace_prog_t *pgp = NULL;
51 	dt_stmt_t *stp;
52 	dtrace_ecbdesc_t *edp;
53 
54 	/*
55 	 * We don't currently support multiple error handlers.
56 	 */
57 	if (dtp->dt_errhdlr != NULL)
58 		return (dt_set_errno(dtp, EALREADY));
59 
60 	/*
61 	 * If the DTRACEOPT_GRABANON is enabled, the anonymous enabling will
62 	 * already have a dtrace:::ERROR probe enabled; save 'hdlr' and 'arg'
63 	 * but do not bother compiling and enabling _dt_errprog.
64 	 */
65 	if (dtp->dt_options[DTRACEOPT_GRABANON] != DTRACEOPT_UNSET)
66 		goto out;
67 
68 	if ((pgp = dtrace_program_strcompile(dtp, _dt_errprog,
69 	    DTRACE_PROBESPEC_NAME, DTRACE_C_ZDEFS, 0, NULL)) == NULL)
70 		return (dt_set_errno(dtp, dtrace_errno(dtp)));
71 
72 	stp = dt_list_next(&pgp->dp_stmts);
73 	assert(stp != NULL);
74 
75 	edp = stp->ds_desc->dtsd_ecbdesc;
76 	assert(edp != NULL);
77 	edp->dted_uarg = DT_ECB_ERROR;
78 
79 out:
80 	dtp->dt_errhdlr = hdlr;
81 	dtp->dt_errarg = arg;
82 	dtp->dt_errprog = pgp;
83 
84 	return (0);
85 }
86 
87 int
dtrace_handle_drop(dtrace_hdl_t * dtp,dtrace_handle_drop_f * hdlr,void * arg)88 dtrace_handle_drop(dtrace_hdl_t *dtp, dtrace_handle_drop_f *hdlr, void *arg)
89 {
90 	if (dtp->dt_drophdlr != NULL)
91 		return (dt_set_errno(dtp, EALREADY));
92 
93 	dtp->dt_drophdlr = hdlr;
94 	dtp->dt_droparg = arg;
95 
96 	return (0);
97 }
98 
99 int
dtrace_handle_proc(dtrace_hdl_t * dtp,dtrace_handle_proc_f * hdlr,void * arg)100 dtrace_handle_proc(dtrace_hdl_t *dtp, dtrace_handle_proc_f *hdlr, void *arg)
101 {
102 	if (dtp->dt_prochdlr != NULL)
103 		return (dt_set_errno(dtp, EALREADY));
104 
105 	dtp->dt_prochdlr = hdlr;
106 	dtp->dt_procarg = arg;
107 
108 	return (0);
109 }
110 
111 int
dtrace_handle_buffered(dtrace_hdl_t * dtp,dtrace_handle_buffered_f * hdlr,void * arg)112 dtrace_handle_buffered(dtrace_hdl_t *dtp, dtrace_handle_buffered_f *hdlr,
113     void *arg)
114 {
115 	if (dtp->dt_bufhdlr != NULL)
116 		return (dt_set_errno(dtp, EALREADY));
117 
118 	if (hdlr == NULL)
119 		return (dt_set_errno(dtp, EINVAL));
120 
121 	dtp->dt_bufhdlr = hdlr;
122 	dtp->dt_bufarg = arg;
123 
124 	return (0);
125 }
126 
127 int
dtrace_handle_setopt(dtrace_hdl_t * dtp,dtrace_handle_setopt_f * hdlr,void * arg)128 dtrace_handle_setopt(dtrace_hdl_t *dtp, dtrace_handle_setopt_f *hdlr,
129     void *arg)
130 {
131 	if (hdlr == NULL)
132 		return (dt_set_errno(dtp, EINVAL));
133 
134 	dtp->dt_setopthdlr = hdlr;
135 	dtp->dt_setoptarg = arg;
136 
137 	return (0);
138 }
139 
140 #define	DT_REC(type, ndx) *((type *)((uintptr_t)data->dtpda_data + \
141     epd->dtepd_rec[(ndx)].dtrd_offset))
142 
143 static int
dt_handle_err(dtrace_hdl_t * dtp,dtrace_probedata_t * data)144 dt_handle_err(dtrace_hdl_t *dtp, dtrace_probedata_t *data)
145 {
146 	dtrace_eprobedesc_t *epd = data->dtpda_edesc, *errepd;
147 	dtrace_probedesc_t *pd = data->dtpda_pdesc, *errpd;
148 	dtrace_errdata_t err;
149 	dtrace_epid_t epid;
150 
151 	char where[30];
152 	char details[30];
153 	char offinfo[30];
154 	const int slop = 80;
155 	const char *faultstr;
156 	char *str;
157 	int len;
158 
159 	assert(epd->dtepd_uarg == DT_ECB_ERROR);
160 
161 	if (epd->dtepd_nrecs != 5 || strcmp(pd->dtpd_provider, "dtrace") != 0 ||
162 	    strcmp(pd->dtpd_name, "ERROR") != 0)
163 		return (dt_set_errno(dtp, EDT_BADERROR));
164 
165 	/*
166 	 * This is an error.  We have the following items here:  EPID,
167 	 * faulting action, DIF offset, fault code and faulting address.
168 	 */
169 	epid = (uint32_t)DT_REC(uint64_t, 0);
170 
171 	if (dt_epid_lookup(dtp, epid, &errepd, &errpd) != 0)
172 		return (dt_set_errno(dtp, EDT_BADERROR));
173 
174 	err.dteda_edesc = errepd;
175 	err.dteda_pdesc = errpd;
176 	err.dteda_cpu = data->dtpda_cpu;
177 	err.dteda_action = (int)DT_REC(uint64_t, 1);
178 	err.dteda_offset = (int)DT_REC(uint64_t, 2);
179 	err.dteda_fault = (int)DT_REC(uint64_t, 3);
180 	err.dteda_addr = DT_REC(uint64_t, 4);
181 
182 	faultstr = dtrace_faultstr(dtp, err.dteda_fault);
183 	len = sizeof (where) + sizeof (offinfo) + strlen(faultstr) +
184 	    strlen(errpd->dtpd_provider) + strlen(errpd->dtpd_mod) +
185 	    strlen(errpd->dtpd_name) + strlen(errpd->dtpd_func) +
186 	    slop;
187 
188 	str = (char *)alloca(len);
189 
190 	if (err.dteda_action == 0) {
191 		(void) sprintf(where, "predicate");
192 	} else {
193 		(void) sprintf(where, "action #%d", err.dteda_action);
194 	}
195 
196 	if (err.dteda_offset != -1) {
197 		(void) sprintf(offinfo, " at DIF offset %d", err.dteda_offset);
198 	} else {
199 		offinfo[0] = 0;
200 	}
201 
202 	switch (err.dteda_fault) {
203 	case DTRACEFLT_BADADDR:
204 	case DTRACEFLT_BADALIGN:
205 	case DTRACEFLT_BADSTACK:
206 		(void) sprintf(details, " (0x%llx)",
207 		    (u_longlong_t)err.dteda_addr);
208 		break;
209 
210 	default:
211 		details[0] = 0;
212 	}
213 
214 	(void) snprintf(str, len, "error on enabled probe ID %u "
215 	    "(ID %u: %s:%s:%s:%s): %s%s in %s%s\n",
216 	    epid, errpd->dtpd_id, errpd->dtpd_provider,
217 	    errpd->dtpd_mod, errpd->dtpd_func,
218 	    errpd->dtpd_name, dtrace_faultstr(dtp, err.dteda_fault),
219 	    details, where, offinfo);
220 
221 	err.dteda_msg = str;
222 
223 	if (dtp->dt_errhdlr == NULL)
224 		return (dt_set_errno(dtp, EDT_ERRABORT));
225 
226 	if ((*dtp->dt_errhdlr)(&err, dtp->dt_errarg) == DTRACE_HANDLE_ABORT)
227 		return (dt_set_errno(dtp, EDT_ERRABORT));
228 
229 	return (0);
230 }
231 
232 int
dt_handle_liberr(dtrace_hdl_t * dtp,const dtrace_probedata_t * data,const char * faultstr)233 dt_handle_liberr(dtrace_hdl_t *dtp, const dtrace_probedata_t *data,
234     const char *faultstr)
235 {
236 	dtrace_probedesc_t *errpd = data->dtpda_pdesc;
237 	dtrace_errdata_t err;
238 	const int slop = 80;
239 	char *str;
240 	int len;
241 
242 	err.dteda_edesc = data->dtpda_edesc;
243 	err.dteda_pdesc = errpd;
244 	err.dteda_cpu = data->dtpda_cpu;
245 	err.dteda_action = -1;
246 	err.dteda_offset = -1;
247 	err.dteda_fault = DTRACEFLT_LIBRARY;
248 	err.dteda_addr = 0;
249 
250 	len = strlen(faultstr) +
251 	    strlen(errpd->dtpd_provider) + strlen(errpd->dtpd_mod) +
252 	    strlen(errpd->dtpd_name) + strlen(errpd->dtpd_func) +
253 	    slop;
254 
255 	str = alloca(len);
256 
257 	(void) snprintf(str, len, "error on enabled probe ID %u "
258 	    "(ID %u: %s:%s:%s:%s): %s\n",
259 	    data->dtpda_edesc->dtepd_epid,
260 	    errpd->dtpd_id, errpd->dtpd_provider,
261 	    errpd->dtpd_mod, errpd->dtpd_func,
262 	    errpd->dtpd_name, faultstr);
263 
264 	err.dteda_msg = str;
265 
266 	if (dtp->dt_errhdlr == NULL)
267 		return (dt_set_errno(dtp, EDT_ERRABORT));
268 
269 	if ((*dtp->dt_errhdlr)(&err, dtp->dt_errarg) == DTRACE_HANDLE_ABORT)
270 		return (dt_set_errno(dtp, EDT_ERRABORT));
271 
272 	return (0);
273 }
274 
275 #define	DROPTAG(x)	x, #x
276 
277 static const struct {
278 	dtrace_dropkind_t dtdrg_kind;
279 	char *dtdrg_tag;
280 } _dt_droptags[] = {
281 	{ DROPTAG(DTRACEDROP_PRINCIPAL) },
282 	{ DROPTAG(DTRACEDROP_AGGREGATION) },
283 	{ DROPTAG(DTRACEDROP_DYNAMIC) },
284 	{ DROPTAG(DTRACEDROP_DYNRINSE) },
285 	{ DROPTAG(DTRACEDROP_DYNDIRTY) },
286 	{ DROPTAG(DTRACEDROP_SPEC) },
287 	{ DROPTAG(DTRACEDROP_SPECBUSY) },
288 	{ DROPTAG(DTRACEDROP_SPECUNAVAIL) },
289 	{ DROPTAG(DTRACEDROP_DBLERROR) },
290 	{ DROPTAG(DTRACEDROP_STKSTROVERFLOW) },
291 	{ 0, NULL }
292 };
293 
294 static const char *
dt_droptag(dtrace_dropkind_t kind)295 dt_droptag(dtrace_dropkind_t kind)
296 {
297 	int i;
298 
299 	for (i = 0; _dt_droptags[i].dtdrg_tag != NULL; i++) {
300 		if (_dt_droptags[i].dtdrg_kind == kind)
301 			return (_dt_droptags[i].dtdrg_tag);
302 	}
303 
304 	return ("DTRACEDROP_UNKNOWN");
305 }
306 
307 int
dt_handle_cpudrop(dtrace_hdl_t * dtp,processorid_t cpu,dtrace_dropkind_t what,uint64_t howmany)308 dt_handle_cpudrop(dtrace_hdl_t *dtp, processorid_t cpu,
309     dtrace_dropkind_t what, uint64_t howmany)
310 {
311 	dtrace_dropdata_t drop;
312 	char str[80], *s;
313 	int size;
314 
315 	assert(what == DTRACEDROP_PRINCIPAL || what == DTRACEDROP_AGGREGATION);
316 
317 	bzero(&drop, sizeof (drop));
318 	drop.dtdda_handle = dtp;
319 	drop.dtdda_cpu = cpu;
320 	drop.dtdda_kind = what;
321 	drop.dtdda_drops = howmany;
322 	drop.dtdda_msg = str;
323 
324 	if (dtp->dt_droptags) {
325 		(void) snprintf(str, sizeof (str), "[%s] ", dt_droptag(what));
326 		s = &str[strlen(str)];
327 		size = sizeof (str) - (s - str);
328 	} else {
329 		s = str;
330 		size = sizeof (str);
331 	}
332 
333 	(void) snprintf(s, size, "%llu %sdrop%s on CPU %d\n",
334 	    howmany, what == DTRACEDROP_PRINCIPAL ? "" : "aggregation ",
335 	    howmany > 1 ? "s" : "", cpu);
336 
337 	if (dtp->dt_drophdlr == NULL)
338 		return (dt_set_errno(dtp, EDT_DROPABORT));
339 
340 	if ((*dtp->dt_drophdlr)(&drop, dtp->dt_droparg) == DTRACE_HANDLE_ABORT)
341 		return (dt_set_errno(dtp, EDT_DROPABORT));
342 
343 	return (0);
344 }
345 
346 static const struct {
347 	dtrace_dropkind_t dtdrt_kind;
348 	uintptr_t dtdrt_offset;
349 	const char *dtdrt_str;
350 	const char *dtdrt_msg;
351 } _dt_droptab[] = {
352 	{ DTRACEDROP_DYNAMIC,
353 	    offsetof(dtrace_status_t, dtst_dyndrops),
354 	    "dynamic variable drop" },
355 
356 	{ DTRACEDROP_DYNRINSE,
357 	    offsetof(dtrace_status_t, dtst_dyndrops_rinsing),
358 	    "dynamic variable drop", " with non-empty rinsing list" },
359 
360 	{ DTRACEDROP_DYNDIRTY,
361 	    offsetof(dtrace_status_t, dtst_dyndrops_dirty),
362 	    "dynamic variable drop", " with non-empty dirty list" },
363 
364 	{ DTRACEDROP_SPEC,
365 	    offsetof(dtrace_status_t, dtst_specdrops),
366 	    "speculative drop" },
367 
368 	{ DTRACEDROP_SPECBUSY,
369 	    offsetof(dtrace_status_t, dtst_specdrops_busy),
370 	    "failed speculation", " (available buffer(s) still busy)" },
371 
372 	{ DTRACEDROP_SPECUNAVAIL,
373 	    offsetof(dtrace_status_t, dtst_specdrops_unavail),
374 	    "failed speculation", " (no speculative buffer available)" },
375 
376 	{ DTRACEDROP_STKSTROVERFLOW,
377 	    offsetof(dtrace_status_t, dtst_stkstroverflows),
378 	    "jstack()/ustack() string table overflow" },
379 
380 	{ DTRACEDROP_DBLERROR,
381 	    offsetof(dtrace_status_t, dtst_dblerrors),
382 	    "error", " in ERROR probe enabling" },
383 
384 	{ 0, 0, NULL }
385 };
386 
387 int
dt_handle_status(dtrace_hdl_t * dtp,dtrace_status_t * old,dtrace_status_t * new)388 dt_handle_status(dtrace_hdl_t *dtp, dtrace_status_t *old, dtrace_status_t *new)
389 {
390 	dtrace_dropdata_t drop;
391 	char str[80], *s;
392 	uintptr_t base = (uintptr_t)new, obase = (uintptr_t)old;
393 	int i, size;
394 
395 	bzero(&drop, sizeof (drop));
396 	drop.dtdda_handle = dtp;
397 	drop.dtdda_cpu = DTRACE_CPUALL;
398 	drop.dtdda_msg = str;
399 
400 	/*
401 	 * First, check to see if we've been killed -- in which case we abort.
402 	 */
403 	if (new->dtst_killed && !old->dtst_killed)
404 		return (dt_set_errno(dtp, EDT_BRICKED));
405 
406 	for (i = 0; _dt_droptab[i].dtdrt_str != NULL; i++) {
407 		uintptr_t naddr = base + _dt_droptab[i].dtdrt_offset;
408 		uintptr_t oaddr = obase + _dt_droptab[i].dtdrt_offset;
409 
410 		uint64_t nval = *((uint64_t *)naddr);
411 		uint64_t oval = *((uint64_t *)oaddr);
412 
413 		if (nval == oval)
414 			continue;
415 
416 		if (dtp->dt_droptags) {
417 			(void) snprintf(str, sizeof (str), "[%s] ",
418 			    dt_droptag(_dt_droptab[i].dtdrt_kind));
419 			s = &str[strlen(str)];
420 			size = sizeof (str) - (s - str);
421 		} else {
422 			s = str;
423 			size = sizeof (str);
424 		}
425 
426 		(void) snprintf(s, size, "%llu %s%s%s\n", nval - oval,
427 		    _dt_droptab[i].dtdrt_str, (nval - oval > 1) ? "s" : "",
428 		    _dt_droptab[i].dtdrt_msg != NULL ?
429 		    _dt_droptab[i].dtdrt_msg : "");
430 
431 		drop.dtdda_kind = _dt_droptab[i].dtdrt_kind;
432 		drop.dtdda_total = nval;
433 		drop.dtdda_drops = nval - oval;
434 
435 		if (dtp->dt_drophdlr == NULL)
436 			return (dt_set_errno(dtp, EDT_DROPABORT));
437 
438 		if ((*dtp->dt_drophdlr)(&drop,
439 		    dtp->dt_droparg) == DTRACE_HANDLE_ABORT)
440 			return (dt_set_errno(dtp, EDT_DROPABORT));
441 	}
442 
443 	return (0);
444 }
445 
446 int
dt_handle_setopt(dtrace_hdl_t * dtp,dtrace_setoptdata_t * data)447 dt_handle_setopt(dtrace_hdl_t *dtp, dtrace_setoptdata_t *data)
448 {
449 	void *arg = dtp->dt_setoptarg;
450 
451 	if (dtp->dt_setopthdlr == NULL)
452 		return (0);
453 
454 	if ((*dtp->dt_setopthdlr)(data, arg) == DTRACE_HANDLE_ABORT)
455 		return (dt_set_errno(dtp, EDT_DIRABORT));
456 
457 	return (0);
458 }
459 
460 int
dt_handle(dtrace_hdl_t * dtp,dtrace_probedata_t * data)461 dt_handle(dtrace_hdl_t *dtp, dtrace_probedata_t *data)
462 {
463 	dtrace_eprobedesc_t *epd = data->dtpda_edesc;
464 	int rval;
465 
466 	switch (epd->dtepd_uarg) {
467 	case DT_ECB_ERROR:
468 		rval = dt_handle_err(dtp, data);
469 		break;
470 
471 	default:
472 		return (DTRACE_CONSUME_THIS);
473 	}
474 
475 	if (rval == 0)
476 		return (DTRACE_CONSUME_NEXT);
477 
478 	return (DTRACE_CONSUME_ERROR);
479 }
480