xref: /freebsd/sys/geom/geom_subr.c (revision 97549c34ecaf74580941fdc9c5bd1050e4b1f6ce)
1 /*-
2  * Copyright (c) 2002 Poul-Henning Kamp
3  * Copyright (c) 2002 Networks Associates Technology, Inc.
4  * All rights reserved.
5  *
6  * This software was developed for the FreeBSD Project by Poul-Henning Kamp
7  * and NAI Labs, the Security Research Division of Network Associates, Inc.
8  * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
9  * DARPA CHATS research program.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. The names of the authors may not be used to endorse or promote
20  *    products derived from this software without specific prior written
21  *    permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD$");
38 
39 #include "opt_ddb.h"
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/devicestat.h>
44 #include <sys/kernel.h>
45 #include <sys/malloc.h>
46 #include <sys/bio.h>
47 #include <sys/sysctl.h>
48 #include <sys/proc.h>
49 #include <sys/kthread.h>
50 #include <sys/lock.h>
51 #include <sys/mutex.h>
52 #include <sys/errno.h>
53 #include <sys/sbuf.h>
54 #include <geom/geom.h>
55 #include <geom/geom_int.h>
56 #include <machine/stdarg.h>
57 
58 #ifdef DDB
59 #include <ddb/ddb.h>
60 #endif
61 
62 #ifdef KDB
63 #include <sys/kdb.h>
64 #endif
65 
66 struct class_list_head g_classes = LIST_HEAD_INITIALIZER(g_classes);
67 static struct g_tailq_head geoms = TAILQ_HEAD_INITIALIZER(geoms);
68 char *g_wait_event, *g_wait_up, *g_wait_down, *g_wait_sim;
69 
70 struct g_hh00 {
71 	struct g_class		*mp;
72 	struct g_provider	*pp;
73 	off_t			size;
74 	int			error;
75 	int			post;
76 };
77 
78 /*
79  * This event offers a new class a chance to taste all preexisting providers.
80  */
81 static void
82 g_load_class(void *arg, int flag)
83 {
84 	struct g_hh00 *hh;
85 	struct g_class *mp2, *mp;
86 	struct g_geom *gp;
87 	struct g_provider *pp;
88 
89 	g_topology_assert();
90 	if (flag == EV_CANCEL)	/* XXX: can't happen ? */
91 		return;
92 	if (g_shutdown)
93 		return;
94 
95 	hh = arg;
96 	mp = hh->mp;
97 	hh->error = 0;
98 	if (hh->post) {
99 		g_free(hh);
100 		hh = NULL;
101 	}
102 	g_trace(G_T_TOPOLOGY, "g_load_class(%s)", mp->name);
103 	KASSERT(mp->name != NULL && *mp->name != '\0',
104 	    ("GEOM class has no name"));
105 	LIST_FOREACH(mp2, &g_classes, class) {
106 		if (mp2 == mp) {
107 			printf("The GEOM class %s is already loaded.\n",
108 			    mp2->name);
109 			if (hh != NULL)
110 				hh->error = EEXIST;
111 			return;
112 		} else if (strcmp(mp2->name, mp->name) == 0) {
113 			printf("A GEOM class %s is already loaded.\n",
114 			    mp2->name);
115 			if (hh != NULL)
116 				hh->error = EEXIST;
117 			return;
118 		}
119 	}
120 
121 	LIST_INIT(&mp->geom);
122 	LIST_INSERT_HEAD(&g_classes, mp, class);
123 	if (mp->init != NULL)
124 		mp->init(mp);
125 	if (mp->taste == NULL)
126 		return;
127 	LIST_FOREACH(mp2, &g_classes, class) {
128 		if (mp == mp2)
129 			continue;
130 		LIST_FOREACH(gp, &mp2->geom, geom) {
131 			LIST_FOREACH(pp, &gp->provider, provider) {
132 				mp->taste(mp, pp, 0);
133 				g_topology_assert();
134 			}
135 		}
136 	}
137 }
138 
139 static int
140 g_unload_class(struct g_class *mp)
141 {
142 	struct g_geom *gp;
143 	struct g_provider *pp;
144 	struct g_consumer *cp;
145 	int error;
146 
147 	g_topology_lock();
148 	g_trace(G_T_TOPOLOGY, "g_unload_class(%s)", mp->name);
149 retry:
150 	G_VALID_CLASS(mp);
151 	LIST_FOREACH(gp, &mp->geom, geom) {
152 		/* We refuse to unload if anything is open */
153 		LIST_FOREACH(pp, &gp->provider, provider)
154 			if (pp->acr || pp->acw || pp->ace) {
155 				g_topology_unlock();
156 				return (EBUSY);
157 			}
158 		LIST_FOREACH(cp, &gp->consumer, consumer)
159 			if (cp->acr || cp->acw || cp->ace) {
160 				g_topology_unlock();
161 				return (EBUSY);
162 			}
163 		/* If the geom is withering, wait for it to finish. */
164 		if (gp->flags & G_GEOM_WITHER) {
165 			g_topology_sleep(mp, 1);
166 			goto retry;
167 		}
168 	}
169 
170 	/*
171 	 * We allow unloading if we have no geoms, or a class
172 	 * method we can use to get rid of them.
173 	 */
174 	if (!LIST_EMPTY(&mp->geom) && mp->destroy_geom == NULL) {
175 		g_topology_unlock();
176 		return (EOPNOTSUPP);
177 	}
178 
179 	/* Bar new entries */
180 	mp->taste = NULL;
181 	mp->config = NULL;
182 
183 	LIST_FOREACH(gp, &mp->geom, geom) {
184 		error = mp->destroy_geom(NULL, mp, gp);
185 		if (error != 0) {
186 			g_topology_unlock();
187 			return (error);
188 		}
189 	}
190 	/* Wait for withering to finish. */
191 	for (;;) {
192 		gp = LIST_FIRST(&mp->geom);
193 		if (gp == NULL)
194 			break;
195 		KASSERT(gp->flags & G_GEOM_WITHER,
196 		   ("Non-withering geom in class %s", mp->name));
197 		g_topology_sleep(mp, 1);
198 	}
199 	G_VALID_CLASS(mp);
200 	if (mp->fini != NULL)
201 		mp->fini(mp);
202 	LIST_REMOVE(mp, class);
203 	g_topology_unlock();
204 
205 	return (0);
206 }
207 
208 int
209 g_modevent(module_t mod, int type, void *data)
210 {
211 	struct g_hh00 *hh;
212 	int error;
213 	static int g_ignition;
214 	struct g_class *mp;
215 
216 	mp = data;
217 	if (mp->version != G_VERSION) {
218 		printf("GEOM class %s has Wrong version %x\n",
219 		    mp->name, mp->version);
220 		return (EINVAL);
221 	}
222 	if (!g_ignition) {
223 		g_ignition++;
224 		g_init();
225 	}
226 	error = EOPNOTSUPP;
227 	switch (type) {
228 	case MOD_LOAD:
229 		g_trace(G_T_TOPOLOGY, "g_modevent(%s, LOAD)", mp->name);
230 		hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
231 		hh->mp = mp;
232 		/*
233 		 * Once the system is not cold, MOD_LOAD calls will be
234 		 * from the userland and the g_event thread will be able
235 		 * to acknowledge their completion.
236 		 */
237 		if (cold) {
238 			hh->post = 1;
239 			error = g_post_event(g_load_class, hh, M_WAITOK, NULL);
240 		} else {
241 			error = g_waitfor_event(g_load_class, hh, M_WAITOK,
242 			    NULL);
243 			if (error == 0)
244 				error = hh->error;
245 			g_free(hh);
246 		}
247 		break;
248 	case MOD_UNLOAD:
249 		g_trace(G_T_TOPOLOGY, "g_modevent(%s, UNLOAD)", mp->name);
250 		error = g_unload_class(mp);
251 		if (error == 0) {
252 			KASSERT(LIST_EMPTY(&mp->geom),
253 			    ("Unloaded class (%s) still has geom", mp->name));
254 		}
255 		break;
256 	}
257 	return (error);
258 }
259 
260 static void
261 g_retaste_event(void *arg, int flag)
262 {
263 	struct g_class *mp, *mp2;
264 	struct g_geom *gp;
265 	struct g_hh00 *hh;
266 	struct g_provider *pp;
267 	struct g_consumer *cp;
268 
269 	g_topology_assert();
270 	if (flag == EV_CANCEL)  /* XXX: can't happen ? */
271 		return;
272 	if (g_shutdown || g_notaste)
273 		return;
274 
275 	hh = arg;
276 	mp = hh->mp;
277 	hh->error = 0;
278 	if (hh->post) {
279 		g_free(hh);
280 		hh = NULL;
281 	}
282 	g_trace(G_T_TOPOLOGY, "g_retaste(%s)", mp->name);
283 
284 	LIST_FOREACH(mp2, &g_classes, class) {
285 		LIST_FOREACH(gp, &mp2->geom, geom) {
286 			LIST_FOREACH(pp, &gp->provider, provider) {
287 				if (pp->acr || pp->acw || pp->ace)
288 					continue;
289 				LIST_FOREACH(cp, &pp->consumers, consumers) {
290 					if (cp->geom->class == mp &&
291 					    (cp->flags & G_CF_ORPHAN) == 0)
292 						break;
293 				}
294 				if (cp != NULL) {
295 					cp->flags |= G_CF_ORPHAN;
296 					g_wither_geom(cp->geom, ENXIO);
297 				}
298 				mp->taste(mp, pp, 0);
299 				g_topology_assert();
300 			}
301 		}
302 	}
303 }
304 
305 int
306 g_retaste(struct g_class *mp)
307 {
308 	struct g_hh00 *hh;
309 	int error;
310 
311 	if (mp->taste == NULL)
312 		return (EINVAL);
313 
314 	hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
315 	hh->mp = mp;
316 
317 	if (cold) {
318 		hh->post = 1;
319 		error = g_post_event(g_retaste_event, hh, M_WAITOK, NULL);
320 	} else {
321 		error = g_waitfor_event(g_retaste_event, hh, M_WAITOK, NULL);
322 		if (error == 0)
323 			error = hh->error;
324 		g_free(hh);
325 	}
326 
327 	return (error);
328 }
329 
330 struct g_geom *
331 g_new_geomf(struct g_class *mp, const char *fmt, ...)
332 {
333 	struct g_geom *gp;
334 	va_list ap;
335 	struct sbuf *sb;
336 
337 	g_topology_assert();
338 	G_VALID_CLASS(mp);
339 	sb = sbuf_new_auto();
340 	va_start(ap, fmt);
341 	sbuf_vprintf(sb, fmt, ap);
342 	va_end(ap);
343 	sbuf_finish(sb);
344 	gp = g_malloc(sizeof *gp, M_WAITOK | M_ZERO);
345 	gp->name = g_malloc(sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
346 	gp->class = mp;
347 	gp->rank = 1;
348 	LIST_INIT(&gp->consumer);
349 	LIST_INIT(&gp->provider);
350 	LIST_INSERT_HEAD(&mp->geom, gp, geom);
351 	TAILQ_INSERT_HEAD(&geoms, gp, geoms);
352 	strcpy(gp->name, sbuf_data(sb));
353 	sbuf_delete(sb);
354 	/* Fill in defaults from class */
355 	gp->start = mp->start;
356 	gp->spoiled = mp->spoiled;
357 	gp->attrchanged = mp->attrchanged;
358 	gp->providergone = mp->providergone;
359 	gp->dumpconf = mp->dumpconf;
360 	gp->access = mp->access;
361 	gp->orphan = mp->orphan;
362 	gp->ioctl = mp->ioctl;
363 	gp->resize = mp->resize;
364 	return (gp);
365 }
366 
367 void
368 g_destroy_geom(struct g_geom *gp)
369 {
370 
371 	g_topology_assert();
372 	G_VALID_GEOM(gp);
373 	g_trace(G_T_TOPOLOGY, "g_destroy_geom(%p(%s))", gp, gp->name);
374 	KASSERT(LIST_EMPTY(&gp->consumer),
375 	    ("g_destroy_geom(%s) with consumer(s) [%p]",
376 	    gp->name, LIST_FIRST(&gp->consumer)));
377 	KASSERT(LIST_EMPTY(&gp->provider),
378 	    ("g_destroy_geom(%s) with provider(s) [%p]",
379 	    gp->name, LIST_FIRST(&gp->provider)));
380 	g_cancel_event(gp);
381 	LIST_REMOVE(gp, geom);
382 	TAILQ_REMOVE(&geoms, gp, geoms);
383 	g_free(gp->name);
384 	g_free(gp);
385 }
386 
387 /*
388  * This function is called (repeatedly) until the geom has withered away.
389  */
390 void
391 g_wither_geom(struct g_geom *gp, int error)
392 {
393 	struct g_provider *pp;
394 
395 	g_topology_assert();
396 	G_VALID_GEOM(gp);
397 	g_trace(G_T_TOPOLOGY, "g_wither_geom(%p(%s))", gp, gp->name);
398 	if (!(gp->flags & G_GEOM_WITHER)) {
399 		gp->flags |= G_GEOM_WITHER;
400 		LIST_FOREACH(pp, &gp->provider, provider)
401 			if (!(pp->flags & G_PF_ORPHAN))
402 				g_orphan_provider(pp, error);
403 	}
404 	g_do_wither();
405 }
406 
407 /*
408  * Convenience function to destroy a particular provider.
409  */
410 void
411 g_wither_provider(struct g_provider *pp, int error)
412 {
413 
414 	pp->flags |= G_PF_WITHER;
415 	if (!(pp->flags & G_PF_ORPHAN))
416 		g_orphan_provider(pp, error);
417 }
418 
419 /*
420  * This function is called (repeatedly) until the has withered away.
421  */
422 void
423 g_wither_geom_close(struct g_geom *gp, int error)
424 {
425 	struct g_consumer *cp;
426 
427 	g_topology_assert();
428 	G_VALID_GEOM(gp);
429 	g_trace(G_T_TOPOLOGY, "g_wither_geom_close(%p(%s))", gp, gp->name);
430 	LIST_FOREACH(cp, &gp->consumer, consumer)
431 		if (cp->acr || cp->acw || cp->ace)
432 			g_access(cp, -cp->acr, -cp->acw, -cp->ace);
433 	g_wither_geom(gp, error);
434 }
435 
436 /*
437  * This function is called (repeatedly) until we cant wash away more
438  * withered bits at present.
439  */
440 void
441 g_wither_washer()
442 {
443 	struct g_class *mp;
444 	struct g_geom *gp, *gp2;
445 	struct g_provider *pp, *pp2;
446 	struct g_consumer *cp, *cp2;
447 
448 	g_topology_assert();
449 	LIST_FOREACH(mp, &g_classes, class) {
450 		LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
451 			LIST_FOREACH_SAFE(pp, &gp->provider, provider, pp2) {
452 				if (!(pp->flags & G_PF_WITHER))
453 					continue;
454 				if (LIST_EMPTY(&pp->consumers))
455 					g_destroy_provider(pp);
456 			}
457 			if (!(gp->flags & G_GEOM_WITHER))
458 				continue;
459 			LIST_FOREACH_SAFE(pp, &gp->provider, provider, pp2) {
460 				if (LIST_EMPTY(&pp->consumers))
461 					g_destroy_provider(pp);
462 			}
463 			LIST_FOREACH_SAFE(cp, &gp->consumer, consumer, cp2) {
464 				if (cp->acr || cp->acw || cp->ace)
465 					continue;
466 				if (cp->provider != NULL)
467 					g_detach(cp);
468 				g_destroy_consumer(cp);
469 			}
470 			if (LIST_EMPTY(&gp->provider) &&
471 			    LIST_EMPTY(&gp->consumer))
472 				g_destroy_geom(gp);
473 		}
474 	}
475 }
476 
477 struct g_consumer *
478 g_new_consumer(struct g_geom *gp)
479 {
480 	struct g_consumer *cp;
481 
482 	g_topology_assert();
483 	G_VALID_GEOM(gp);
484 	KASSERT(!(gp->flags & G_GEOM_WITHER),
485 	    ("g_new_consumer on WITHERing geom(%s) (class %s)",
486 	    gp->name, gp->class->name));
487 	KASSERT(gp->orphan != NULL,
488 	    ("g_new_consumer on geom(%s) (class %s) without orphan",
489 	    gp->name, gp->class->name));
490 
491 	cp = g_malloc(sizeof *cp, M_WAITOK | M_ZERO);
492 	cp->geom = gp;
493 	cp->stat = devstat_new_entry(cp, -1, 0, DEVSTAT_ALL_SUPPORTED,
494 	    DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
495 	LIST_INSERT_HEAD(&gp->consumer, cp, consumer);
496 	return(cp);
497 }
498 
499 void
500 g_destroy_consumer(struct g_consumer *cp)
501 {
502 	struct g_geom *gp;
503 
504 	g_topology_assert();
505 	G_VALID_CONSUMER(cp);
506 	g_trace(G_T_TOPOLOGY, "g_destroy_consumer(%p)", cp);
507 	KASSERT (cp->provider == NULL, ("g_destroy_consumer but attached"));
508 	KASSERT (cp->acr == 0, ("g_destroy_consumer with acr"));
509 	KASSERT (cp->acw == 0, ("g_destroy_consumer with acw"));
510 	KASSERT (cp->ace == 0, ("g_destroy_consumer with ace"));
511 	g_cancel_event(cp);
512 	gp = cp->geom;
513 	LIST_REMOVE(cp, consumer);
514 	devstat_remove_entry(cp->stat);
515 	g_free(cp);
516 	if (gp->flags & G_GEOM_WITHER)
517 		g_do_wither();
518 }
519 
520 static void
521 g_new_provider_event(void *arg, int flag)
522 {
523 	struct g_class *mp;
524 	struct g_provider *pp;
525 	struct g_consumer *cp, *next_cp;
526 
527 	g_topology_assert();
528 	if (flag == EV_CANCEL)
529 		return;
530 	if (g_shutdown)
531 		return;
532 	pp = arg;
533 	G_VALID_PROVIDER(pp);
534 	KASSERT(!(pp->flags & G_PF_WITHER),
535 	    ("g_new_provider_event but withered"));
536 	LIST_FOREACH_SAFE(cp, &pp->consumers, consumers, next_cp) {
537 		if ((cp->flags & G_CF_ORPHAN) == 0 &&
538 		    cp->geom->attrchanged != NULL)
539 			cp->geom->attrchanged(cp, "GEOM::media");
540 	}
541 	if (g_notaste)
542 		return;
543 	LIST_FOREACH(mp, &g_classes, class) {
544 		if (mp->taste == NULL)
545 			continue;
546 		LIST_FOREACH(cp, &pp->consumers, consumers)
547 			if (cp->geom->class == mp &&
548 			    (cp->flags & G_CF_ORPHAN) == 0)
549 				break;
550 		if (cp != NULL)
551 			continue;
552 		mp->taste(mp, pp, 0);
553 		g_topology_assert();
554 	}
555 }
556 
557 
558 struct g_provider *
559 g_new_providerf(struct g_geom *gp, const char *fmt, ...)
560 {
561 	struct g_provider *pp;
562 	struct sbuf *sb;
563 	va_list ap;
564 
565 	g_topology_assert();
566 	G_VALID_GEOM(gp);
567 	KASSERT(gp->access != NULL,
568 	    ("new provider on geom(%s) without ->access (class %s)",
569 	    gp->name, gp->class->name));
570 	KASSERT(gp->start != NULL,
571 	    ("new provider on geom(%s) without ->start (class %s)",
572 	    gp->name, gp->class->name));
573 	KASSERT(!(gp->flags & G_GEOM_WITHER),
574 	    ("new provider on WITHERing geom(%s) (class %s)",
575 	    gp->name, gp->class->name));
576 	sb = sbuf_new_auto();
577 	va_start(ap, fmt);
578 	sbuf_vprintf(sb, fmt, ap);
579 	va_end(ap);
580 	sbuf_finish(sb);
581 	pp = g_malloc(sizeof *pp + sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
582 	pp->name = (char *)(pp + 1);
583 	strcpy(pp->name, sbuf_data(sb));
584 	sbuf_delete(sb);
585 	LIST_INIT(&pp->consumers);
586 	pp->error = ENXIO;
587 	pp->geom = gp;
588 	pp->stat = devstat_new_entry(pp, -1, 0, DEVSTAT_ALL_SUPPORTED,
589 	    DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
590 	LIST_INSERT_HEAD(&gp->provider, pp, provider);
591 	g_post_event(g_new_provider_event, pp, M_WAITOK, pp, gp, NULL);
592 	return (pp);
593 }
594 
595 void
596 g_error_provider(struct g_provider *pp, int error)
597 {
598 
599 	/* G_VALID_PROVIDER(pp);  We may not have g_topology */
600 	pp->error = error;
601 }
602 
603 static void
604 g_resize_provider_event(void *arg, int flag)
605 {
606 	struct g_hh00 *hh;
607 	struct g_class *mp;
608 	struct g_geom *gp;
609 	struct g_provider *pp;
610 	struct g_consumer *cp, *cp2;
611 	off_t size;
612 
613 	g_topology_assert();
614 	if (g_shutdown)
615 		return;
616 
617 	hh = arg;
618 	pp = hh->pp;
619 	size = hh->size;
620 	g_free(hh);
621 
622 	G_VALID_PROVIDER(pp);
623 	KASSERT(!(pp->flags & G_PF_WITHER),
624 	    ("g_resize_provider_event but withered"));
625 	g_trace(G_T_TOPOLOGY, "g_resize_provider_event(%p)", pp);
626 
627 	LIST_FOREACH_SAFE(cp, &pp->consumers, consumers, cp2) {
628 		gp = cp->geom;
629 		if (gp->resize == NULL && size < pp->mediasize) {
630 			cp->flags |= G_CF_ORPHAN;
631 			cp->geom->orphan(cp);
632 		}
633 	}
634 
635 	pp->mediasize = size;
636 
637 	LIST_FOREACH_SAFE(cp, &pp->consumers, consumers, cp2) {
638 		gp = cp->geom;
639 		if ((gp->flags & G_GEOM_WITHER) == 0 && gp->resize != NULL)
640 			gp->resize(cp);
641 	}
642 
643 	/*
644 	 * After resizing, the previously invalid GEOM class metadata
645 	 * might become valid.  This means we should retaste.
646 	 */
647 	LIST_FOREACH(mp, &g_classes, class) {
648 		if (mp->taste == NULL)
649 			continue;
650 		LIST_FOREACH(cp, &pp->consumers, consumers)
651 			if (cp->geom->class == mp &&
652 			    (cp->flags & G_CF_ORPHAN) == 0)
653 				break;
654 		if (cp != NULL)
655 			continue;
656 		mp->taste(mp, pp, 0);
657 		g_topology_assert();
658 	}
659 }
660 
661 void
662 g_resize_provider(struct g_provider *pp, off_t size)
663 {
664 	struct g_hh00 *hh;
665 
666 	G_VALID_PROVIDER(pp);
667 	if (pp->flags & G_PF_WITHER)
668 		return;
669 
670 	if (size == pp->mediasize)
671 		return;
672 
673 	hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
674 	hh->pp = pp;
675 	hh->size = size;
676 	g_post_event(g_resize_provider_event, hh, M_WAITOK, NULL);
677 }
678 
679 #ifndef	_PATH_DEV
680 #define	_PATH_DEV	"/dev/"
681 #endif
682 
683 struct g_provider *
684 g_provider_by_name(char const *arg)
685 {
686 	struct g_class *cp;
687 	struct g_geom *gp;
688 	struct g_provider *pp, *wpp;
689 
690 	if (strncmp(arg, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
691 		arg += sizeof(_PATH_DEV) - 1;
692 
693 	wpp = NULL;
694 	LIST_FOREACH(cp, &g_classes, class) {
695 		LIST_FOREACH(gp, &cp->geom, geom) {
696 			LIST_FOREACH(pp, &gp->provider, provider) {
697 				if (strcmp(arg, pp->name) != 0)
698 					continue;
699 				if ((gp->flags & G_GEOM_WITHER) == 0 &&
700 				    (pp->flags & G_PF_WITHER) == 0)
701 					return (pp);
702 				else
703 					wpp = pp;
704 			}
705 		}
706 	}
707 
708 	return (wpp);
709 }
710 
711 void
712 g_destroy_provider(struct g_provider *pp)
713 {
714 	struct g_geom *gp;
715 
716 	g_topology_assert();
717 	G_VALID_PROVIDER(pp);
718 	KASSERT(LIST_EMPTY(&pp->consumers),
719 	    ("g_destroy_provider but attached"));
720 	KASSERT (pp->acr == 0, ("g_destroy_provider with acr"));
721 	KASSERT (pp->acw == 0, ("g_destroy_provider with acw"));
722 	KASSERT (pp->ace == 0, ("g_destroy_provider with ace"));
723 	g_cancel_event(pp);
724 	LIST_REMOVE(pp, provider);
725 	gp = pp->geom;
726 	devstat_remove_entry(pp->stat);
727 	/*
728 	 * If a callback was provided, send notification that the provider
729 	 * is now gone.
730 	 */
731 	if (gp->providergone != NULL)
732 		gp->providergone(pp);
733 
734 	g_free(pp);
735 	if ((gp->flags & G_GEOM_WITHER))
736 		g_do_wither();
737 }
738 
739 /*
740  * We keep the "geoms" list sorted by topological order (== increasing
741  * numerical rank) at all times.
742  * When an attach is done, the attaching geoms rank is invalidated
743  * and it is moved to the tail of the list.
744  * All geoms later in the sequence has their ranks reevaluated in
745  * sequence.  If we cannot assign rank to a geom because it's
746  * prerequisites do not have rank, we move that element to the tail
747  * of the sequence with invalid rank as well.
748  * At some point we encounter our original geom and if we stil fail
749  * to assign it a rank, there must be a loop and we fail back to
750  * g_attach() which detach again and calls redo_rank again
751  * to fix up the damage.
752  * It would be much simpler code wise to do it recursively, but we
753  * can't risk that on the kernel stack.
754  */
755 
756 static int
757 redo_rank(struct g_geom *gp)
758 {
759 	struct g_consumer *cp;
760 	struct g_geom *gp1, *gp2;
761 	int n, m;
762 
763 	g_topology_assert();
764 	G_VALID_GEOM(gp);
765 
766 	/* Invalidate this geoms rank and move it to the tail */
767 	gp1 = TAILQ_NEXT(gp, geoms);
768 	if (gp1 != NULL) {
769 		gp->rank = 0;
770 		TAILQ_REMOVE(&geoms, gp, geoms);
771 		TAILQ_INSERT_TAIL(&geoms, gp, geoms);
772 	} else {
773 		gp1 = gp;
774 	}
775 
776 	/* re-rank the rest of the sequence */
777 	for (; gp1 != NULL; gp1 = gp2) {
778 		gp1->rank = 0;
779 		m = 1;
780 		LIST_FOREACH(cp, &gp1->consumer, consumer) {
781 			if (cp->provider == NULL)
782 				continue;
783 			n = cp->provider->geom->rank;
784 			if (n == 0) {
785 				m = 0;
786 				break;
787 			} else if (n >= m)
788 				m = n + 1;
789 		}
790 		gp1->rank = m;
791 		gp2 = TAILQ_NEXT(gp1, geoms);
792 
793 		/* got a rank, moving on */
794 		if (m != 0)
795 			continue;
796 
797 		/* no rank to original geom means loop */
798 		if (gp == gp1)
799 			return (ELOOP);
800 
801 		/* no rank, put it at the end move on */
802 		TAILQ_REMOVE(&geoms, gp1, geoms);
803 		TAILQ_INSERT_TAIL(&geoms, gp1, geoms);
804 	}
805 	return (0);
806 }
807 
808 int
809 g_attach(struct g_consumer *cp, struct g_provider *pp)
810 {
811 	int error;
812 
813 	g_topology_assert();
814 	G_VALID_CONSUMER(cp);
815 	G_VALID_PROVIDER(pp);
816 	g_trace(G_T_TOPOLOGY, "g_attach(%p, %p)", cp, pp);
817 	KASSERT(cp->provider == NULL, ("attach but attached"));
818 	cp->provider = pp;
819 	LIST_INSERT_HEAD(&pp->consumers, cp, consumers);
820 	error = redo_rank(cp->geom);
821 	if (error) {
822 		LIST_REMOVE(cp, consumers);
823 		cp->provider = NULL;
824 		redo_rank(cp->geom);
825 	}
826 	return (error);
827 }
828 
829 void
830 g_detach(struct g_consumer *cp)
831 {
832 	struct g_provider *pp;
833 
834 	g_topology_assert();
835 	G_VALID_CONSUMER(cp);
836 	g_trace(G_T_TOPOLOGY, "g_detach(%p)", cp);
837 	KASSERT(cp->provider != NULL, ("detach but not attached"));
838 	KASSERT(cp->acr == 0, ("detach but nonzero acr"));
839 	KASSERT(cp->acw == 0, ("detach but nonzero acw"));
840 	KASSERT(cp->ace == 0, ("detach but nonzero ace"));
841 	KASSERT(cp->nstart == cp->nend,
842 	    ("detach with active requests"));
843 	pp = cp->provider;
844 	LIST_REMOVE(cp, consumers);
845 	cp->provider = NULL;
846 	if ((cp->geom->flags & G_GEOM_WITHER) ||
847 	    (pp->geom->flags & G_GEOM_WITHER) ||
848 	    (pp->flags & G_PF_WITHER))
849 		g_do_wither();
850 	redo_rank(cp->geom);
851 }
852 
853 /*
854  * g_access()
855  *
856  * Access-check with delta values.  The question asked is "can provider
857  * "cp" change the access counters by the relative amounts dc[rwe] ?"
858  */
859 
860 int
861 g_access(struct g_consumer *cp, int dcr, int dcw, int dce)
862 {
863 	struct g_provider *pp;
864 	int pr,pw,pe;
865 	int error;
866 
867 	g_topology_assert();
868 	G_VALID_CONSUMER(cp);
869 	pp = cp->provider;
870 	KASSERT(pp != NULL, ("access but not attached"));
871 	G_VALID_PROVIDER(pp);
872 
873 	g_trace(G_T_ACCESS, "g_access(%p(%s), %d, %d, %d)",
874 	    cp, pp->name, dcr, dcw, dce);
875 
876 	KASSERT(cp->acr + dcr >= 0, ("access resulting in negative acr"));
877 	KASSERT(cp->acw + dcw >= 0, ("access resulting in negative acw"));
878 	KASSERT(cp->ace + dce >= 0, ("access resulting in negative ace"));
879 	KASSERT(dcr != 0 || dcw != 0 || dce != 0, ("NOP access request"));
880 	KASSERT(pp->geom->access != NULL, ("NULL geom->access"));
881 
882 	/*
883 	 * If our class cares about being spoiled, and we have been, we
884 	 * are probably just ahead of the event telling us that.  Fail
885 	 * now rather than having to unravel this later.
886 	 */
887 	if (cp->geom->spoiled != NULL && (cp->flags & G_CF_SPOILED) &&
888 	    (dcr > 0 || dcw > 0 || dce > 0))
889 		return (ENXIO);
890 
891 	/*
892 	 * Figure out what counts the provider would have had, if this
893 	 * consumer had (r0w0e0) at this time.
894 	 */
895 	pr = pp->acr - cp->acr;
896 	pw = pp->acw - cp->acw;
897 	pe = pp->ace - cp->ace;
898 
899 	g_trace(G_T_ACCESS,
900     "open delta:[r%dw%de%d] old:[r%dw%de%d] provider:[r%dw%de%d] %p(%s)",
901 	    dcr, dcw, dce,
902 	    cp->acr, cp->acw, cp->ace,
903 	    pp->acr, pp->acw, pp->ace,
904 	    pp, pp->name);
905 
906 	/* If foot-shooting is enabled, any open on rank#1 is OK */
907 	if ((g_debugflags & 16) && pp->geom->rank == 1)
908 		;
909 	/* If we try exclusive but already write: fail */
910 	else if (dce > 0 && pw > 0)
911 		return (EPERM);
912 	/* If we try write but already exclusive: fail */
913 	else if (dcw > 0 && pe > 0)
914 		return (EPERM);
915 	/* If we try to open more but provider is error'ed: fail */
916 	else if ((dcr > 0 || dcw > 0 || dce > 0) && pp->error != 0) {
917 		printf("%s(%d): provider %s has error\n",
918 		       __func__, __LINE__, pp->name);
919 		return (pp->error);
920 	}
921 
922 	/* Ok then... */
923 
924 	error = pp->geom->access(pp, dcr, dcw, dce);
925 	KASSERT(dcr > 0 || dcw > 0 || dce > 0 || error == 0,
926 	    ("Geom provider %s::%s dcr=%d dcw=%d dce=%d error=%d failed "
927 	    "closing ->access()", pp->geom->class->name, pp->name, dcr, dcw,
928 	    dce, error));
929 	if (!error) {
930 		/*
931 		 * If we open first write, spoil any partner consumers.
932 		 * If we close last write and provider is not errored,
933 		 * trigger re-taste.
934 		 */
935 		if (pp->acw == 0 && dcw != 0)
936 			g_spoil(pp, cp);
937 		else if (pp->acw != 0 && pp->acw == -dcw && pp->error == 0 &&
938 		    !(pp->geom->flags & G_GEOM_WITHER))
939 			g_post_event(g_new_provider_event, pp, M_WAITOK,
940 			    pp, NULL);
941 
942 		pp->acr += dcr;
943 		pp->acw += dcw;
944 		pp->ace += dce;
945 		cp->acr += dcr;
946 		cp->acw += dcw;
947 		cp->ace += dce;
948 		if (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)
949 			KASSERT(pp->sectorsize > 0,
950 			    ("Provider %s lacks sectorsize", pp->name));
951 		if ((cp->geom->flags & G_GEOM_WITHER) &&
952 		    cp->acr == 0 && cp->acw == 0 && cp->ace == 0)
953 			g_do_wither();
954 	}
955 	return (error);
956 }
957 
958 int
959 g_handleattr_int(struct bio *bp, const char *attribute, int val)
960 {
961 
962 	return (g_handleattr(bp, attribute, &val, sizeof val));
963 }
964 
965 int
966 g_handleattr_uint16_t(struct bio *bp, const char *attribute, uint16_t val)
967 {
968 
969 	return (g_handleattr(bp, attribute, &val, sizeof val));
970 }
971 
972 int
973 g_handleattr_off_t(struct bio *bp, const char *attribute, off_t val)
974 {
975 
976 	return (g_handleattr(bp, attribute, &val, sizeof val));
977 }
978 
979 int
980 g_handleattr_str(struct bio *bp, const char *attribute, const char *str)
981 {
982 
983 	return (g_handleattr(bp, attribute, str, 0));
984 }
985 
986 int
987 g_handleattr(struct bio *bp, const char *attribute, const void *val, int len)
988 {
989 	int error = 0;
990 
991 	if (strcmp(bp->bio_attribute, attribute))
992 		return (0);
993 	if (len == 0) {
994 		bzero(bp->bio_data, bp->bio_length);
995 		if (strlcpy(bp->bio_data, val, bp->bio_length) >=
996 		    bp->bio_length) {
997 			printf("%s: %s bio_length %jd len %zu -> EFAULT\n",
998 			    __func__, bp->bio_to->name,
999 			    (intmax_t)bp->bio_length, strlen(val));
1000 			error = EFAULT;
1001 		}
1002 	} else if (bp->bio_length == len) {
1003 		bcopy(val, bp->bio_data, len);
1004 	} else {
1005 		printf("%s: %s bio_length %jd len %d -> EFAULT\n", __func__,
1006 		    bp->bio_to->name, (intmax_t)bp->bio_length, len);
1007 		error = EFAULT;
1008 	}
1009 	if (error == 0)
1010 		bp->bio_completed = bp->bio_length;
1011 	g_io_deliver(bp, error);
1012 	return (1);
1013 }
1014 
1015 int
1016 g_std_access(struct g_provider *pp,
1017 	int dr __unused, int dw __unused, int de __unused)
1018 {
1019 
1020 	g_topology_assert();
1021 	G_VALID_PROVIDER(pp);
1022         return (0);
1023 }
1024 
1025 void
1026 g_std_done(struct bio *bp)
1027 {
1028 	struct bio *bp2;
1029 
1030 	bp2 = bp->bio_parent;
1031 	if (bp2->bio_error == 0)
1032 		bp2->bio_error = bp->bio_error;
1033 	bp2->bio_completed += bp->bio_completed;
1034 	g_destroy_bio(bp);
1035 	bp2->bio_inbed++;
1036 	if (bp2->bio_children == bp2->bio_inbed)
1037 		g_io_deliver(bp2, bp2->bio_error);
1038 }
1039 
1040 /* XXX: maybe this is only g_slice_spoiled */
1041 
1042 void
1043 g_std_spoiled(struct g_consumer *cp)
1044 {
1045 	struct g_geom *gp;
1046 	struct g_provider *pp;
1047 
1048 	g_topology_assert();
1049 	G_VALID_CONSUMER(cp);
1050 	g_trace(G_T_TOPOLOGY, "g_std_spoiled(%p)", cp);
1051 	cp->flags |= G_CF_ORPHAN;
1052 	g_detach(cp);
1053 	gp = cp->geom;
1054 	LIST_FOREACH(pp, &gp->provider, provider)
1055 		g_orphan_provider(pp, ENXIO);
1056 	g_destroy_consumer(cp);
1057 	if (LIST_EMPTY(&gp->provider) && LIST_EMPTY(&gp->consumer))
1058 		g_destroy_geom(gp);
1059 	else
1060 		gp->flags |= G_GEOM_WITHER;
1061 }
1062 
1063 /*
1064  * Spoiling happens when a provider is opened for writing, but consumers
1065  * which are configured by in-band data are attached (slicers for instance).
1066  * Since the write might potentially change the in-band data, such consumers
1067  * need to re-evaluate their existence after the writing session closes.
1068  * We do this by (offering to) tear them down when the open for write happens
1069  * in return for a re-taste when it closes again.
1070  * Together with the fact that such consumers grab an 'e' bit whenever they
1071  * are open, regardless of mode, this ends up DTRT.
1072  */
1073 
1074 static void
1075 g_spoil_event(void *arg, int flag)
1076 {
1077 	struct g_provider *pp;
1078 	struct g_consumer *cp, *cp2;
1079 
1080 	g_topology_assert();
1081 	if (flag == EV_CANCEL)
1082 		return;
1083 	pp = arg;
1084 	G_VALID_PROVIDER(pp);
1085 	g_trace(G_T_TOPOLOGY, "%s %p(%s:%s:%s)", __func__, pp,
1086 	    pp->geom->class->name, pp->geom->name, pp->name);
1087 	for (cp = LIST_FIRST(&pp->consumers); cp != NULL; cp = cp2) {
1088 		cp2 = LIST_NEXT(cp, consumers);
1089 		if ((cp->flags & G_CF_SPOILED) == 0)
1090 			continue;
1091 		cp->flags &= ~G_CF_SPOILED;
1092 		if (cp->geom->spoiled == NULL)
1093 			continue;
1094 		cp->geom->spoiled(cp);
1095 		g_topology_assert();
1096 	}
1097 }
1098 
1099 void
1100 g_spoil(struct g_provider *pp, struct g_consumer *cp)
1101 {
1102 	struct g_consumer *cp2;
1103 
1104 	g_topology_assert();
1105 	G_VALID_PROVIDER(pp);
1106 	G_VALID_CONSUMER(cp);
1107 
1108 	LIST_FOREACH(cp2, &pp->consumers, consumers) {
1109 		if (cp2 == cp)
1110 			continue;
1111 /*
1112 		KASSERT(cp2->acr == 0, ("spoiling cp->acr = %d", cp2->acr));
1113 		KASSERT(cp2->acw == 0, ("spoiling cp->acw = %d", cp2->acw));
1114 */
1115 		KASSERT(cp2->ace == 0, ("spoiling cp->ace = %d", cp2->ace));
1116 		cp2->flags |= G_CF_SPOILED;
1117 	}
1118 	g_post_event(g_spoil_event, pp, M_WAITOK, pp, NULL);
1119 }
1120 
1121 static void
1122 g_media_changed_event(void *arg, int flag)
1123 {
1124 	struct g_provider *pp;
1125 	int retaste;
1126 
1127 	g_topology_assert();
1128 	if (flag == EV_CANCEL)
1129 		return;
1130 	pp = arg;
1131 	G_VALID_PROVIDER(pp);
1132 
1133 	/*
1134 	 * If provider was not open for writing, queue retaste after spoiling.
1135 	 * If it was, retaste will happen automatically on close.
1136 	 */
1137 	retaste = (pp->acw == 0 && pp->error == 0 &&
1138 	    !(pp->geom->flags & G_GEOM_WITHER));
1139 	g_spoil_event(arg, flag);
1140 	if (retaste)
1141 		g_post_event(g_new_provider_event, pp, M_WAITOK, pp, NULL);
1142 }
1143 
1144 int
1145 g_media_changed(struct g_provider *pp, int flag)
1146 {
1147 	struct g_consumer *cp;
1148 
1149 	LIST_FOREACH(cp, &pp->consumers, consumers)
1150 		cp->flags |= G_CF_SPOILED;
1151 	return (g_post_event(g_media_changed_event, pp, flag, pp, NULL));
1152 }
1153 
1154 int
1155 g_media_gone(struct g_provider *pp, int flag)
1156 {
1157 	struct g_consumer *cp;
1158 
1159 	LIST_FOREACH(cp, &pp->consumers, consumers)
1160 		cp->flags |= G_CF_SPOILED;
1161 	return (g_post_event(g_spoil_event, pp, flag, pp, NULL));
1162 }
1163 
1164 int
1165 g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len)
1166 {
1167 	int error, i;
1168 
1169 	i = len;
1170 	error = g_io_getattr(attr, cp, &i, var);
1171 	if (error)
1172 		return (error);
1173 	if (i != len)
1174 		return (EINVAL);
1175 	return (0);
1176 }
1177 
1178 static int
1179 g_get_device_prefix_len(const char *name)
1180 {
1181 	int len;
1182 
1183 	if (strncmp(name, "ada", 3) == 0)
1184 		len = 3;
1185 	else if (strncmp(name, "ad", 2) == 0)
1186 		len = 2;
1187 	else
1188 		return (0);
1189 	if (name[len] < '0' || name[len] > '9')
1190 		return (0);
1191 	do {
1192 		len++;
1193 	} while (name[len] >= '0' && name[len] <= '9');
1194 	return (len);
1195 }
1196 
1197 int
1198 g_compare_names(const char *namea, const char *nameb)
1199 {
1200 	int deva, devb;
1201 
1202 	if (strcmp(namea, nameb) == 0)
1203 		return (1);
1204 	deva = g_get_device_prefix_len(namea);
1205 	if (deva == 0)
1206 		return (0);
1207 	devb = g_get_device_prefix_len(nameb);
1208 	if (devb == 0)
1209 		return (0);
1210 	if (strcmp(namea + deva, nameb + devb) == 0)
1211 		return (1);
1212 	return (0);
1213 }
1214 
1215 #if defined(DIAGNOSTIC) || defined(DDB)
1216 /*
1217  * This function walks the mesh and returns a non-zero integer if it
1218  * finds the argument pointer is an object. The return value indicates
1219  * which type of object it is believed to be. If topology is not locked,
1220  * this function is potentially dangerous, but we don't assert that the
1221  * topology lock is held when called from debugger.
1222  */
1223 int
1224 g_valid_obj(void const *ptr)
1225 {
1226 	struct g_class *mp;
1227 	struct g_geom *gp;
1228 	struct g_consumer *cp;
1229 	struct g_provider *pp;
1230 
1231 #ifdef KDB
1232 	if (kdb_active == 0)
1233 #endif
1234 		g_topology_assert();
1235 
1236 	LIST_FOREACH(mp, &g_classes, class) {
1237 		if (ptr == mp)
1238 			return (1);
1239 		LIST_FOREACH(gp, &mp->geom, geom) {
1240 			if (ptr == gp)
1241 				return (2);
1242 			LIST_FOREACH(cp, &gp->consumer, consumer)
1243 				if (ptr == cp)
1244 					return (3);
1245 			LIST_FOREACH(pp, &gp->provider, provider)
1246 				if (ptr == pp)
1247 					return (4);
1248 		}
1249 	}
1250 	return(0);
1251 }
1252 #endif
1253 
1254 #ifdef DDB
1255 
1256 #define	gprintf(...)	do {						\
1257 	db_printf("%*s", indent, "");					\
1258 	db_printf(__VA_ARGS__);						\
1259 } while (0)
1260 #define	gprintln(...)	do {						\
1261 	gprintf(__VA_ARGS__);						\
1262 	db_printf("\n");						\
1263 } while (0)
1264 
1265 #define	ADDFLAG(obj, flag, sflag)	do {				\
1266 	if ((obj)->flags & (flag)) {					\
1267 		if (comma)						\
1268 			strlcat(str, ",", size);			\
1269 		strlcat(str, (sflag), size);				\
1270 		comma = 1;						\
1271 	}								\
1272 } while (0)
1273 
1274 static char *
1275 provider_flags_to_string(struct g_provider *pp, char *str, size_t size)
1276 {
1277 	int comma = 0;
1278 
1279 	bzero(str, size);
1280 	if (pp->flags == 0) {
1281 		strlcpy(str, "NONE", size);
1282 		return (str);
1283 	}
1284 	ADDFLAG(pp, G_PF_WITHER, "G_PF_WITHER");
1285 	ADDFLAG(pp, G_PF_ORPHAN, "G_PF_ORPHAN");
1286 	return (str);
1287 }
1288 
1289 static char *
1290 geom_flags_to_string(struct g_geom *gp, char *str, size_t size)
1291 {
1292 	int comma = 0;
1293 
1294 	bzero(str, size);
1295 	if (gp->flags == 0) {
1296 		strlcpy(str, "NONE", size);
1297 		return (str);
1298 	}
1299 	ADDFLAG(gp, G_GEOM_WITHER, "G_GEOM_WITHER");
1300 	return (str);
1301 }
1302 static void
1303 db_show_geom_consumer(int indent, struct g_consumer *cp)
1304 {
1305 
1306 	if (indent == 0) {
1307 		gprintln("consumer: %p", cp);
1308 		gprintln("  class:    %s (%p)", cp->geom->class->name,
1309 		    cp->geom->class);
1310 		gprintln("  geom:     %s (%p)", cp->geom->name, cp->geom);
1311 		if (cp->provider == NULL)
1312 			gprintln("  provider: none");
1313 		else {
1314 			gprintln("  provider: %s (%p)", cp->provider->name,
1315 			    cp->provider);
1316 		}
1317 		gprintln("  access:   r%dw%de%d", cp->acr, cp->acw, cp->ace);
1318 		gprintln("  flags:    0x%04x", cp->flags);
1319 		gprintln("  nstart:   %u", cp->nstart);
1320 		gprintln("  nend:     %u", cp->nend);
1321 	} else {
1322 		gprintf("consumer: %p (%s), access=r%dw%de%d", cp,
1323 		    cp->provider != NULL ? cp->provider->name : "none",
1324 		    cp->acr, cp->acw, cp->ace);
1325 		if (cp->flags)
1326 			db_printf(", flags=0x%04x", cp->flags);
1327 		db_printf("\n");
1328 	}
1329 }
1330 
1331 static void
1332 db_show_geom_provider(int indent, struct g_provider *pp)
1333 {
1334 	struct g_consumer *cp;
1335 	char flags[64];
1336 
1337 	if (indent == 0) {
1338 		gprintln("provider: %s (%p)", pp->name, pp);
1339 		gprintln("  class:        %s (%p)", pp->geom->class->name,
1340 		    pp->geom->class);
1341 		gprintln("  geom:         %s (%p)", pp->geom->name, pp->geom);
1342 		gprintln("  mediasize:    %jd", (intmax_t)pp->mediasize);
1343 		gprintln("  sectorsize:   %u", pp->sectorsize);
1344 		gprintln("  stripesize:   %u", pp->stripesize);
1345 		gprintln("  stripeoffset: %u", pp->stripeoffset);
1346 		gprintln("  access:       r%dw%de%d", pp->acr, pp->acw,
1347 		    pp->ace);
1348 		gprintln("  flags:        %s (0x%04x)",
1349 		    provider_flags_to_string(pp, flags, sizeof(flags)),
1350 		    pp->flags);
1351 		gprintln("  error:        %d", pp->error);
1352 		gprintln("  nstart:       %u", pp->nstart);
1353 		gprintln("  nend:         %u", pp->nend);
1354 		if (LIST_EMPTY(&pp->consumers))
1355 			gprintln("  consumers:    none");
1356 	} else {
1357 		gprintf("provider: %s (%p), access=r%dw%de%d",
1358 		    pp->name, pp, pp->acr, pp->acw, pp->ace);
1359 		if (pp->flags != 0) {
1360 			db_printf(", flags=%s (0x%04x)",
1361 			    provider_flags_to_string(pp, flags, sizeof(flags)),
1362 			    pp->flags);
1363 		}
1364 		db_printf("\n");
1365 	}
1366 	if (!LIST_EMPTY(&pp->consumers)) {
1367 		LIST_FOREACH(cp, &pp->consumers, consumers) {
1368 			db_show_geom_consumer(indent + 2, cp);
1369 			if (db_pager_quit)
1370 				break;
1371 		}
1372 	}
1373 }
1374 
1375 static void
1376 db_show_geom_geom(int indent, struct g_geom *gp)
1377 {
1378 	struct g_provider *pp;
1379 	struct g_consumer *cp;
1380 	char flags[64];
1381 
1382 	if (indent == 0) {
1383 		gprintln("geom: %s (%p)", gp->name, gp);
1384 		gprintln("  class:     %s (%p)", gp->class->name, gp->class);
1385 		gprintln("  flags:     %s (0x%04x)",
1386 		    geom_flags_to_string(gp, flags, sizeof(flags)), gp->flags);
1387 		gprintln("  rank:      %d", gp->rank);
1388 		if (LIST_EMPTY(&gp->provider))
1389 			gprintln("  providers: none");
1390 		if (LIST_EMPTY(&gp->consumer))
1391 			gprintln("  consumers: none");
1392 	} else {
1393 		gprintf("geom: %s (%p), rank=%d", gp->name, gp, gp->rank);
1394 		if (gp->flags != 0) {
1395 			db_printf(", flags=%s (0x%04x)",
1396 			    geom_flags_to_string(gp, flags, sizeof(flags)),
1397 			    gp->flags);
1398 		}
1399 		db_printf("\n");
1400 	}
1401 	if (!LIST_EMPTY(&gp->provider)) {
1402 		LIST_FOREACH(pp, &gp->provider, provider) {
1403 			db_show_geom_provider(indent + 2, pp);
1404 			if (db_pager_quit)
1405 				break;
1406 		}
1407 	}
1408 	if (!LIST_EMPTY(&gp->consumer)) {
1409 		LIST_FOREACH(cp, &gp->consumer, consumer) {
1410 			db_show_geom_consumer(indent + 2, cp);
1411 			if (db_pager_quit)
1412 				break;
1413 		}
1414 	}
1415 }
1416 
1417 static void
1418 db_show_geom_class(struct g_class *mp)
1419 {
1420 	struct g_geom *gp;
1421 
1422 	db_printf("class: %s (%p)\n", mp->name, mp);
1423 	LIST_FOREACH(gp, &mp->geom, geom) {
1424 		db_show_geom_geom(2, gp);
1425 		if (db_pager_quit)
1426 			break;
1427 	}
1428 }
1429 
1430 /*
1431  * Print the GEOM topology or the given object.
1432  */
1433 DB_SHOW_COMMAND(geom, db_show_geom)
1434 {
1435 	struct g_class *mp;
1436 
1437 	if (!have_addr) {
1438 		/* No address given, print the entire topology. */
1439 		LIST_FOREACH(mp, &g_classes, class) {
1440 			db_show_geom_class(mp);
1441 			db_printf("\n");
1442 			if (db_pager_quit)
1443 				break;
1444 		}
1445 	} else {
1446 		switch (g_valid_obj((void *)addr)) {
1447 		case 1:
1448 			db_show_geom_class((struct g_class *)addr);
1449 			break;
1450 		case 2:
1451 			db_show_geom_geom(0, (struct g_geom *)addr);
1452 			break;
1453 		case 3:
1454 			db_show_geom_consumer(0, (struct g_consumer *)addr);
1455 			break;
1456 		case 4:
1457 			db_show_geom_provider(0, (struct g_provider *)addr);
1458 			break;
1459 		default:
1460 			db_printf("Not a GEOM object.\n");
1461 			break;
1462 		}
1463 	}
1464 }
1465 
1466 static void
1467 db_print_bio_cmd(struct bio *bp)
1468 {
1469 	db_printf("  cmd: ");
1470 	switch (bp->bio_cmd) {
1471 	case BIO_READ: db_printf("BIO_READ"); break;
1472 	case BIO_WRITE: db_printf("BIO_WRITE"); break;
1473 	case BIO_DELETE: db_printf("BIO_DELETE"); break;
1474 	case BIO_GETATTR: db_printf("BIO_GETATTR"); break;
1475 	case BIO_FLUSH: db_printf("BIO_FLUSH"); break;
1476 	case BIO_CMD0: db_printf("BIO_CMD0"); break;
1477 	case BIO_CMD1: db_printf("BIO_CMD1"); break;
1478 	case BIO_CMD2: db_printf("BIO_CMD2"); break;
1479 	case BIO_ZONE: db_printf("BIO_ZONE"); break;
1480 	default: db_printf("UNKNOWN"); break;
1481 	}
1482 	db_printf("\n");
1483 }
1484 
1485 static void
1486 db_print_bio_flags(struct bio *bp)
1487 {
1488 	int comma;
1489 
1490 	comma = 0;
1491 	db_printf("  flags: ");
1492 	if (bp->bio_flags & BIO_ERROR) {
1493 		db_printf("BIO_ERROR");
1494 		comma = 1;
1495 	}
1496 	if (bp->bio_flags & BIO_DONE) {
1497 		db_printf("%sBIO_DONE", (comma ? ", " : ""));
1498 		comma = 1;
1499 	}
1500 	if (bp->bio_flags & BIO_ONQUEUE)
1501 		db_printf("%sBIO_ONQUEUE", (comma ? ", " : ""));
1502 	db_printf("\n");
1503 }
1504 
1505 /*
1506  * Print useful information in a BIO
1507  */
1508 DB_SHOW_COMMAND(bio, db_show_bio)
1509 {
1510 	struct bio *bp;
1511 
1512 	if (have_addr) {
1513 		bp = (struct bio *)addr;
1514 		db_printf("BIO %p\n", bp);
1515 		db_print_bio_cmd(bp);
1516 		db_print_bio_flags(bp);
1517 		db_printf("  cflags: 0x%hx\n", bp->bio_cflags);
1518 		db_printf("  pflags: 0x%hx\n", bp->bio_pflags);
1519 		db_printf("  offset: %jd\n", (intmax_t)bp->bio_offset);
1520 		db_printf("  length: %jd\n", (intmax_t)bp->bio_length);
1521 		db_printf("  bcount: %ld\n", bp->bio_bcount);
1522 		db_printf("  resid: %ld\n", bp->bio_resid);
1523 		db_printf("  completed: %jd\n", (intmax_t)bp->bio_completed);
1524 		db_printf("  children: %u\n", bp->bio_children);
1525 		db_printf("  inbed: %u\n", bp->bio_inbed);
1526 		db_printf("  error: %d\n", bp->bio_error);
1527 		db_printf("  parent: %p\n", bp->bio_parent);
1528 		db_printf("  driver1: %p\n", bp->bio_driver1);
1529 		db_printf("  driver2: %p\n", bp->bio_driver2);
1530 		db_printf("  caller1: %p\n", bp->bio_caller1);
1531 		db_printf("  caller2: %p\n", bp->bio_caller2);
1532 		db_printf("  bio_from: %p\n", bp->bio_from);
1533 		db_printf("  bio_to: %p\n", bp->bio_to);
1534 	}
1535 }
1536 
1537 #undef	gprintf
1538 #undef	gprintln
1539 #undef	ADDFLAG
1540 
1541 #endif	/* DDB */
1542