xref: /titanic_41/usr/src/uts/common/os/logsubr.c (revision 3ad28c1e51ef5773481ccea340f94723d9d7b1aa)
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 /*
23  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/types.h>
30 #include <sys/param.h>
31 #include <sys/varargs.h>
32 #include <sys/systm.h>
33 #include <sys/cmn_err.h>
34 #include <sys/stream.h>
35 #include <sys/strsubr.h>
36 #include <sys/strsun.h>
37 #include <sys/sysmacros.h>
38 #include <sys/kmem.h>
39 #include <sys/log.h>
40 #include <sys/spl.h>
41 #include <sys/syslog.h>
42 #include <sys/console.h>
43 #include <sys/debug.h>
44 #include <sys/utsname.h>
45 #include <sys/id_space.h>
46 #include <sys/zone.h>
47 
48 log_zone_t log_global;
49 queue_t *log_consq;
50 queue_t *log_backlogq;
51 queue_t *log_intrq;
52 
53 #define	LOG_PRISIZE	8	/* max priority size: 7 characters + null */
54 #define	LOG_FACSIZE	9	/* max priority size: 8 characters + null */
55 
56 static krwlock_t log_rwlock;
57 static int log_rwlock_depth;
58 static int log_seq_no[SL_CONSOLE + 1];
59 static stdata_t log_fakestr;
60 static id_space_t *log_minorspace;
61 static log_t log_backlog;
62 static struct kmem_cache *log_cons_cache;	/* log_t cache */
63 
64 static queue_t *log_recentq;
65 static queue_t *log_freeq;
66 
67 static zone_key_t log_zone_key;
68 
69 static char log_overflow_msg[] = "message overflow on /dev/log minor #%d%s\n";
70 
71 static char log_pri[LOG_PRIMASK + 1][LOG_PRISIZE] = {
72 	"emerg",	"alert",	"crit",		"error",
73 	"warning",	"notice",	"info",		"debug"
74 };
75 
76 static char log_fac[LOG_NFACILITIES + 1][LOG_FACSIZE] = {
77 	"kern",		"user",		"mail",		"daemon",
78 	"auth",		"syslog",	"lpr",		"news",
79 	"uucp",		"resv9",	"resv10",	"resv11",
80 	"resv12",	"audit",	"resv14",	"cron",
81 	"local0",	"local1",	"local2",	"local3",
82 	"local4",	"local5",	"local6",	"local7",
83 	"unknown"
84 };
85 static int log_cons_constructor(void *, void *, int);
86 static void log_cons_destructor(void *, void *);
87 
88 /*
89  * Get exclusive access to the logging system; this includes all minor
90  * devices.  We use an rwlock rather than a mutex because hold times
91  * are potentially long, so we don't want to waste cycles in adaptive mutex
92  * spin (rwlocks always block when contended).  Note that we explicitly
93  * support recursive calls (e.g. printf() calls foo() calls printf()).
94  *
95  * Clients may use log_enter() / log_exit() to guarantee that a group
96  * of messages is treated atomically (i.e. they appear in order and are
97  * not interspersed with any other messages), e.g. for multiline printf().
98  *
99  * This could probably be changed to a per-zone lock if contention becomes
100  * an issue.
101  */
102 void
103 log_enter(void)
104 {
105 	if (rw_owner(&log_rwlock) != curthread)
106 		rw_enter(&log_rwlock, RW_WRITER);
107 	log_rwlock_depth++;
108 }
109 
110 void
111 log_exit(void)
112 {
113 	if (--log_rwlock_depth == 0)
114 		rw_exit(&log_rwlock);
115 }
116 
117 void
118 log_flushq(queue_t *q)
119 {
120 	mblk_t *mp;
121 	log_t *lp = (log_t *)q->q_ptr;
122 
123 	/* lp will be NULL if the queue was created via log_makeq */
124 	while ((mp = getq_noenab(q)) != NULL)
125 		log_sendmsg(mp, lp == NULL ? GLOBAL_ZONEID : lp->log_zoneid);
126 }
127 
128 /*
129  * Create a minimal queue with just enough fields filled in to support
130  * canput(9F), putq(9F), and getq_noenab(9F).  We set QNOENB to ensure
131  * that the queue will never be enabled.
132  */
133 static queue_t *
134 log_makeq(size_t lowat, size_t hiwat, void *ibc)
135 {
136 	queue_t *q;
137 
138 	q = kmem_zalloc(sizeof (queue_t), KM_SLEEP);
139 	q->q_stream = &log_fakestr;
140 	q->q_flag = QISDRV | QMTSAFE | QNOENB | QREADR | QUSE;
141 	q->q_nfsrv = q;
142 	q->q_lowat = lowat;
143 	q->q_hiwat = hiwat;
144 	mutex_init(QLOCK(q), NULL, MUTEX_DRIVER, ibc);
145 
146 	return (q);
147 }
148 
149 /*
150  * Initialize the log structure for a new zone.
151  */
152 static void *
153 log_zoneinit(zoneid_t zoneid)
154 {
155 	int i;
156 	log_zone_t *lzp;
157 
158 	if (zoneid == GLOBAL_ZONEID)
159 		lzp = &log_global;	/* use statically allocated struct */
160 	else
161 		lzp = kmem_zalloc(sizeof (log_zone_t), KM_SLEEP);
162 
163 	for (i = 0; i < LOG_NUMCLONES; i++) {
164 		lzp->lz_clones[i].log_minor =
165 		    (minor_t)id_alloc(log_minorspace);
166 		lzp->lz_clones[i].log_zoneid = zoneid;
167 	}
168 	return (lzp);
169 }
170 
171 /*ARGSUSED*/
172 static void
173 log_zonefree(zoneid_t zoneid, void *arg)
174 {
175 	log_zone_t *lzp = arg;
176 	int i;
177 
178 	ASSERT(lzp != &log_global && zoneid != GLOBAL_ZONEID);
179 	if (lzp == NULL)
180 		return;
181 	for (i = 0; i < LOG_NUMCLONES; i++)
182 		id_free(log_minorspace, lzp->lz_clones[i].log_minor);
183 	kmem_free(lzp, sizeof (log_zone_t));
184 }
185 
186 void
187 log_init(void)
188 {
189 	int log_maxzones;
190 
191 	/*
192 	 * Create a backlog queue to consume console messages during periods
193 	 * when there is no console reader (e.g. before syslogd(1M) starts).
194 	 */
195 	log_backlogq = log_consq = log_makeq(0, LOG_HIWAT, NULL);
196 
197 	/*
198 	 * Create a queue to hold free message of size <= LOG_MSGSIZE.
199 	 * Calls from high-level interrupt handlers will do a getq_noenab()
200 	 * from this queue, so its q_lock must be a maximum SPL spin lock.
201 	 */
202 	log_freeq = log_makeq(LOG_MINFREE, LOG_MAXFREE, (void *)ipltospl(SPL8));
203 
204 	/*
205 	 * Create a queue for messages from high-level interrupt context.
206 	 * These messages are drained via softcall, or explicitly by panic().
207 	 */
208 	log_intrq = log_makeq(0, LOG_HIWAT, (void *)ipltospl(SPL8));
209 
210 	/*
211 	 * Create a queue to hold the most recent 8K of console messages.
212 	 * Useful for debugging.  Required by the "$<msgbuf" adb macro.
213 	 */
214 	log_recentq = log_makeq(0, LOG_RECENTSIZE, NULL);
215 
216 	/*
217 	 * Create an id space for clone devices opened via /dev/log.
218 	 * Need to limit the number of zones to avoid exceeding the
219 	 * available minor number space.
220 	 */
221 	log_maxzones = (L_MAXMIN32 - LOG_LOGMIN) / LOG_NUMCLONES - 1;
222 	if (log_maxzones < maxzones)
223 		maxzones = log_maxzones;
224 	log_minorspace = id_space_create("logminor_space", LOG_LOGMIN + 1,
225 	    L_MAXMIN32);
226 	/*
227 	 * Put ourselves on the ZSD list.  Note that zones have not been
228 	 * initialized yet, but our constructor will be called on the global
229 	 * zone when they are.
230 	 */
231 	zone_key_create(&log_zone_key, log_zoneinit, NULL, log_zonefree);
232 
233 	/*
234 	 * Initialize backlog structure.
235 	 */
236 	log_backlog.log_zoneid = GLOBAL_ZONEID;
237 	log_backlog.log_minor = LOG_BACKLOG;
238 
239 	/* Allocate kmem cache for conslog's log structures */
240 	log_cons_cache = kmem_cache_create("log_cons_cache",
241 	    sizeof (struct log), 0, log_cons_constructor, log_cons_destructor,
242 	    NULL, NULL, NULL, 0);
243 
244 	/*
245 	 * Let the logging begin.
246 	 */
247 	log_update(&log_backlog, log_backlogq, SL_CONSOLE, log_console);
248 
249 	/*
250 	 * Now that logging is enabled, emit the SunOS banner.
251 	 */
252 	printf("\rSunOS Release %s Version %s %u-bit\n",
253 	    utsname.release, utsname.version, NBBY * (uint_t)sizeof (void *));
254 	printf("Copyright 1983-2006 Sun Microsystems, Inc.  "
255 		"All rights reserved.\nUse is subject to license terms.\n");
256 #ifdef DEBUG
257 	printf("DEBUG enabled\n");
258 #endif
259 }
260 
261 /*
262  * Allocate a log device corresponding to supplied device type.
263  * Both devices are clonable. /dev/log devices are allocated per zone.
264  * /dev/conslog devices are allocated from kmem cache.
265  */
266 log_t *
267 log_alloc(minor_t type)
268 {
269 	zone_t *zptr = curproc->p_zone;
270 	log_zone_t *lzp;
271 	log_t *lp;
272 	int i;
273 	minor_t minor;
274 
275 	if (type == LOG_CONSMIN) {
276 
277 		/*
278 		 * Return a write-only /dev/conslog device.
279 		 * No point allocating log_t until there's a free minor number.
280 		 */
281 		minor = (minor_t)id_alloc(log_minorspace);
282 		lp = kmem_cache_alloc(log_cons_cache, KM_SLEEP);
283 		lp->log_minor = minor;
284 		return (lp);
285 	} else {
286 		ASSERT(type == LOG_LOGMIN);
287 
288 		lzp = zone_getspecific(log_zone_key, zptr);
289 		ASSERT(lzp != NULL);
290 
291 		/* search for an available /dev/log device for the zone */
292 		for (i = LOG_LOGMINIDX; i <= LOG_LOGMAXIDX; i++) {
293 			lp = &lzp->lz_clones[i];
294 			if (lp->log_inuse == 0)
295 				break;
296 		}
297 		if (i > LOG_LOGMAXIDX)
298 			lp = NULL;
299 		else
300 			/* Indicate which device type */
301 			lp->log_major = LOG_LOGMIN;
302 		return (lp);
303 	}
304 }
305 
306 void
307 log_free(log_t *lp)
308 {
309 	id_free(log_minorspace, lp->log_minor);
310 	kmem_cache_free(log_cons_cache, lp);
311 }
312 
313 /*
314  * Move console messages from src to dst.  The time of day isn't known
315  * early in boot, so fix up the message timestamps if necessary.
316  */
317 static void
318 log_conswitch(log_t *src, log_t *dst)
319 {
320 	mblk_t *mp;
321 	mblk_t *hmp = NULL;
322 	mblk_t *tmp = NULL;
323 	log_ctl_t *hlc;
324 
325 	while ((mp = getq_noenab(src->log_q)) != NULL) {
326 		log_ctl_t *lc = (log_ctl_t *)mp->b_rptr;
327 		lc->flags |= SL_LOGONLY;
328 
329 		/*
330 		 * In the early boot phase hrestime is invalid.
331 		 * hrestime becomes valid when clock() runs for the first time.
332 		 * At this time is lbolt == 1. log_sendmsg() saves the lbolt
333 		 * value in ltime.
334 		 */
335 		if (lc->ltime < 2) {
336 			/*
337 			 * Look ahead to first early boot message with time.
338 			 */
339 			if (hmp) {
340 				tmp->b_next = mp;
341 				tmp = mp;
342 			} else
343 				hmp = tmp = mp;
344 			continue;
345 		}
346 
347 		while (hmp) {
348 			tmp = hmp->b_next;
349 			hmp->b_next = NULL;
350 			hlc = (log_ctl_t *)hmp->b_rptr;
351 			/*
352 			 * Calculate hrestime for an early log message with
353 			 * an invalid time stamp. We know:
354 			 *  - the lbolt of the invalid time stamp.
355 			 *  - the hrestime and lbolt of the first valid
356 			 *    time stamp.
357 			 */
358 			hlc->ttime = lc->ttime - (lc->ltime - hlc->ltime) / hz;
359 			(void) putq(dst->log_q, hmp);
360 			hmp = tmp;
361 		}
362 		(void) putq(dst->log_q, mp);
363 	}
364 	while (hmp) {
365 		tmp = hmp->b_next;
366 		hmp->b_next = NULL;
367 		hlc = (log_ctl_t *)hmp->b_rptr;
368 		hlc->ttime = gethrestime_sec() - (lbolt - hlc->ltime) / hz;
369 		(void) putq(dst->log_q, hmp);
370 		hmp = tmp;
371 	}
372 	dst->log_overflow = src->log_overflow;
373 	src->log_flags = 0;
374 	dst->log_flags = SL_CONSOLE;
375 	log_consq = dst->log_q;
376 }
377 
378 /*
379  * Set the fields in the 'target' clone to the specified values.
380  * Then, look at all clones to determine which message types are
381  * currently active and which clone is the primary console queue.
382  * If the primary console queue changes to or from the backlog
383  * queue, copy all messages from backlog to primary or vice versa.
384  */
385 void
386 log_update(log_t *target, queue_t *q, short flags, log_filter_t *filter)
387 {
388 	log_t *lp;
389 	short active = SL_CONSOLE;
390 	zone_t *zptr = NULL;
391 	log_zone_t *lzp;
392 	zoneid_t zoneid = target->log_zoneid;
393 	int i;
394 
395 	log_enter();
396 
397 	if (q != NULL)
398 		target->log_q = q;
399 	target->log_wanted = filter;
400 	target->log_flags = flags;
401 	target->log_overflow = 0;
402 
403 	/*
404 	 * Need to special case the global zone here since this may be
405 	 * called before zone_init.
406 	 */
407 	if (zoneid == GLOBAL_ZONEID) {
408 		lzp = &log_global;
409 	} else if ((zptr = zone_find_by_id(zoneid)) == NULL) {
410 		log_exit();
411 		return;		/* zone is being destroyed, ignore update */
412 	} else {
413 		lzp = zone_getspecific(log_zone_key, zptr);
414 	}
415 	ASSERT(lzp != NULL);
416 	for (i = LOG_LOGMAXIDX; i >= LOG_LOGMINIDX; i--) {
417 		lp = &lzp->lz_clones[i];
418 		if (zoneid == GLOBAL_ZONEID && (lp->log_flags & SL_CONSOLE))
419 			log_consq = lp->log_q;
420 		active |= lp->log_flags;
421 	}
422 	lzp->lz_active = active;
423 
424 	if (zptr)
425 		zone_rele(zptr);
426 
427 	if (log_consq == target->log_q) {
428 		if (flags & SL_CONSOLE)
429 			log_conswitch(&log_backlog, target);
430 		else
431 			log_conswitch(target, &log_backlog);
432 	}
433 	target->log_q = q;
434 
435 	log_exit();
436 }
437 
438 /*ARGSUSED*/
439 int
440 log_error(log_t *lp, log_ctl_t *lc)
441 {
442 	if ((lc->pri & LOG_FACMASK) == LOG_KERN)
443 		lc->pri = LOG_KERN | LOG_ERR;
444 	return (1);
445 }
446 
447 int
448 log_trace(log_t *lp, log_ctl_t *lc)
449 {
450 	trace_ids_t *tid = (trace_ids_t *)lp->log_data->b_rptr;
451 	trace_ids_t *tidend = (trace_ids_t *)lp->log_data->b_wptr;
452 
453 	/*
454 	 * We use `tid + 1 <= tidend' here rather than the more traditional
455 	 * `tid < tidend', since the former ensures that there's at least
456 	 * `sizeof (trace_ids_t)' bytes available before executing the
457 	 * loop, whereas the latter only ensures that there's a single byte.
458 	 */
459 	for (; tid + 1 <= tidend; tid++) {
460 		if (tid->ti_level < lc->level && tid->ti_level >= 0)
461 			continue;
462 		if (tid->ti_mid != lc->mid && tid->ti_mid >= 0)
463 			continue;
464 		if (tid->ti_sid != lc->sid && tid->ti_sid >= 0)
465 			continue;
466 		if ((lc->pri & LOG_FACMASK) == LOG_KERN)
467 			lc->pri = LOG_KERN | LOG_DEBUG;
468 		return (1);
469 	}
470 	return (0);
471 }
472 
473 /*ARGSUSED*/
474 int
475 log_console(log_t *lp, log_ctl_t *lc)
476 {
477 	if ((lc->pri & LOG_FACMASK) == LOG_KERN) {
478 		if (lc->flags & SL_FATAL)
479 			lc->pri = LOG_KERN | LOG_CRIT;
480 		else if (lc->flags & SL_ERROR)
481 			lc->pri = LOG_KERN | LOG_ERR;
482 		else if (lc->flags & SL_WARN)
483 			lc->pri = LOG_KERN | LOG_WARNING;
484 		else if (lc->flags & SL_NOTE)
485 			lc->pri = LOG_KERN | LOG_NOTICE;
486 		else if (lc->flags & SL_TRACE)
487 			lc->pri = LOG_KERN | LOG_DEBUG;
488 		else
489 			lc->pri = LOG_KERN | LOG_INFO;
490 	}
491 	return (1);
492 }
493 
494 mblk_t *
495 log_makemsg(int mid, int sid, int level, int sl, int pri, void *msg,
496 	size_t size, int on_intr)
497 {
498 	mblk_t *mp = NULL;
499 	mblk_t *mp2;
500 	log_ctl_t *lc;
501 
502 	if (size <= LOG_MSGSIZE &&
503 	    (on_intr || log_freeq->q_count > log_freeq->q_lowat))
504 		mp = getq_noenab(log_freeq);
505 
506 	if (mp == NULL) {
507 		if (on_intr ||
508 		    (mp = allocb(sizeof (log_ctl_t), BPRI_HI)) == NULL ||
509 		    (mp2 = allocb(MAX(size, LOG_MSGSIZE), BPRI_HI)) == NULL) {
510 			freemsg(mp);
511 			return (NULL);
512 		}
513 		DB_TYPE(mp) = M_PROTO;
514 		mp->b_wptr += sizeof (log_ctl_t);
515 		mp->b_cont = mp2;
516 	} else {
517 		mp2 = mp->b_cont;
518 		mp2->b_wptr = mp2->b_rptr;
519 	}
520 
521 	lc = (log_ctl_t *)mp->b_rptr;
522 	lc->mid = mid;
523 	lc->sid = sid;
524 	lc->level = level;
525 	lc->flags = sl;
526 	lc->pri = pri;
527 
528 	bcopy(msg, mp2->b_wptr, size - 1);
529 	mp2->b_wptr[size - 1] = '\0';
530 	mp2->b_wptr += strlen((char *)mp2->b_wptr) + 1;
531 
532 	return (mp);
533 }
534 
535 void
536 log_freemsg(mblk_t *mp)
537 {
538 	mblk_t *mp2 = mp->b_cont;
539 
540 	ASSERT(MBLKL(mp) == sizeof (log_ctl_t));
541 	ASSERT(mp2->b_rptr == mp2->b_datap->db_base);
542 
543 	if ((log_freeq->q_flag & QFULL) == 0 &&
544 	    MBLKL(mp2) <= LOG_MSGSIZE && MBLKSIZE(mp2) >= LOG_MSGSIZE)
545 		(void) putq(log_freeq, mp);
546 	else
547 		freemsg(mp);
548 }
549 
550 void
551 log_sendmsg(mblk_t *mp, zoneid_t zoneid)
552 {
553 	log_t *lp;
554 	char *src, *dst;
555 	mblk_t *mp2 = mp->b_cont;
556 	log_ctl_t *lc = (log_ctl_t *)mp->b_rptr;
557 	int flags, fac;
558 	off_t facility = 0;
559 	off_t body = 0;
560 	zone_t *zptr = NULL;
561 	log_zone_t *lzp;
562 	int i;
563 	int backlog;
564 
565 	/*
566 	 * Need to special case the global zone here since this may be
567 	 * called before zone_init.
568 	 */
569 	if (zoneid == GLOBAL_ZONEID) {
570 		lzp = &log_global;
571 	} else if ((zptr = zone_find_by_id(zoneid)) == NULL) {
572 		/* specified zone doesn't exist, free message and return */
573 		log_freemsg(mp);
574 		return;
575 	} else {
576 		lzp = zone_getspecific(log_zone_key, zptr);
577 	}
578 	ASSERT(lzp != NULL);
579 
580 	if ((lc->flags & lzp->lz_active) == 0) {
581 		if (zptr)
582 			zone_rele(zptr);
583 		log_freemsg(mp);
584 		return;
585 	}
586 
587 	if (panicstr) {
588 		/*
589 		 * Raise the console queue's q_hiwat to ensure that we
590 		 * capture all panic messages.
591 		 */
592 		log_consq->q_hiwat = 2 * LOG_HIWAT;
593 		log_consq->q_flag &= ~QFULL;
594 
595 		/* Message was created while panicking. */
596 		lc->flags |= SL_PANICMSG;
597 	}
598 
599 	src = (char *)mp2->b_rptr;
600 	dst = strstr(src, "FACILITY_AND_PRIORITY] ");
601 	if (dst != NULL) {
602 		facility = dst - src;
603 		body = facility + 23; /* strlen("FACILITY_AND_PRIORITY] ") */
604 	}
605 
606 	log_enter();
607 
608 	lc->ltime = lbolt;
609 	lc->ttime = gethrestime_sec();
610 
611 	flags = lc->flags & lzp->lz_active;
612 	log_seq_no[flags & SL_ERROR]++;
613 	log_seq_no[flags & SL_TRACE]++;
614 	log_seq_no[flags & SL_CONSOLE]++;
615 
616 	/*
617 	 * If this is in the global zone, start with the backlog, then
618 	 * walk through the clone logs.  If not, just do the clone logs.
619 	 */
620 	backlog = (zoneid == GLOBAL_ZONEID);
621 	i = LOG_LOGMINIDX;
622 	while (i <= LOG_LOGMAXIDX) {
623 		if (backlog) {
624 			/*
625 			 * Do the backlog this time, then start on the
626 			 * others.
627 			 */
628 			backlog = 0;
629 			lp = &log_backlog;
630 		} else {
631 			lp = &lzp->lz_clones[i++];
632 		}
633 
634 		if ((lp->log_flags & flags) && lp->log_wanted(lp, lc)) {
635 			if (canput(lp->log_q)) {
636 				lp->log_overflow = 0;
637 				lc->seq_no = log_seq_no[lp->log_flags];
638 				if ((mp2 = copymsg(mp)) == NULL)
639 					break;
640 				if (facility != 0) {
641 					src = (char *)mp2->b_cont->b_rptr;
642 					dst = src + facility;
643 					fac = (lc->pri & LOG_FACMASK) >> 3;
644 					dst += snprintf(dst,
645 					    LOG_FACSIZE + LOG_PRISIZE, "%s.%s",
646 					    log_fac[MIN(fac, LOG_NFACILITIES)],
647 					    log_pri[lc->pri & LOG_PRIMASK]);
648 					src += body - 2; /* copy "] " too */
649 					while (*src != '\0')
650 						*dst++ = *src++;
651 					*dst++ = '\0';
652 					mp2->b_cont->b_wptr = (uchar_t *)dst;
653 				}
654 				(void) putq(lp->log_q, mp2);
655 			} else if (++lp->log_overflow == 1) {
656 				if (lp->log_q == log_consq) {
657 					console_printf(log_overflow_msg,
658 					    lp->log_minor,
659 					    " -- is syslogd(1M) running?");
660 				} else {
661 					printf(log_overflow_msg,
662 					    lp->log_minor, "");
663 				}
664 			}
665 		}
666 	}
667 
668 	if (zptr)
669 		zone_rele(zptr);
670 
671 	if ((flags & SL_CONSOLE) && (lc->pri & LOG_FACMASK) == LOG_KERN) {
672 		if ((mp2 == NULL || log_consq == log_backlogq || panicstr) &&
673 		    (lc->flags & SL_LOGONLY) == 0)
674 			console_printf("%s", (char *)mp->b_cont->b_rptr + body);
675 		if ((lc->flags & SL_CONSONLY) == 0 &&
676 		    (mp2 = copymsg(mp)) != NULL) {
677 			mp2->b_cont->b_rptr += body;
678 			if (log_recentq->q_flag & QFULL)
679 				freemsg(getq_noenab(log_recentq));
680 			(void) putq(log_recentq, mp2);
681 		}
682 	}
683 
684 	log_freemsg(mp);
685 
686 	log_exit();
687 }
688 
689 /*
690  * Print queued messages to console.
691  */
692 void
693 log_printq(queue_t *qfirst)
694 {
695 	mblk_t *mp;
696 	queue_t *q, *qlast;
697 	char *cp, *msgp;
698 	log_ctl_t *lc;
699 
700 	/*
701 	 * Look ahead to first queued message in the stream.
702 	 */
703 	qlast = NULL;
704 	do {
705 		for (q = qfirst; q->q_next != qlast; q = q->q_next)
706 			continue;
707 		for (mp = q->q_first; mp != NULL; mp = mp->b_next) {
708 			lc = (log_ctl_t *)mp->b_rptr;
709 			/*
710 			 * Check if message is already displayed at
711 			 * /dev/console.
712 			 */
713 			if (lc->flags & SL_PANICMSG)
714 				continue;
715 
716 			cp = (char *)mp->b_cont->b_rptr;
717 
718 			/* Strip off the message ID. */
719 			if ((msgp = strstr(cp, "[ID ")) != NULL &&
720 			    (msgp = strstr(msgp,  "] ")) != NULL) {
721 				cp = msgp + 2;
722 			}
723 
724 			/*
725 			 * Using console_printf instead of printf to avoid
726 			 * queueing messages to log_consq.
727 			 */
728 			console_printf("%s", cp);
729 		}
730 	} while ((qlast = q) != qfirst);
731 }
732 
733 /* ARGSUSED */
734 static int
735 log_cons_constructor(void *buf, void *cdrarg, int kmflags)
736 {
737 	struct log *lp = buf;
738 
739 	lp->log_zoneid = GLOBAL_ZONEID;
740 	lp->log_major = LOG_CONSMIN;	/* Indicate which device type */
741 	lp->log_data = NULL;
742 	return (0);
743 }
744 
745 /* ARGSUSED */
746 static void
747 log_cons_destructor(void *buf, void *cdrarg)
748 {
749 	struct log *lp = buf;
750 
751 	ASSERT(lp->log_zoneid == GLOBAL_ZONEID);
752 	ASSERT(lp->log_major == LOG_CONSMIN);
753 	ASSERT(lp->log_data == NULL);
754 }
755