xref: /freebsd/sys/geom/geom_subr.c (revision f39bffc62c1395bde25d152c7f68fdf7cbaab414)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2002 Poul-Henning Kamp
5  * Copyright (c) 2002 Networks Associates Technology, Inc.
6  * All rights reserved.
7  *
8  * This software was developed for the FreeBSD Project by Poul-Henning Kamp
9  * and NAI Labs, the Security Research Division of Network Associates, Inc.
10  * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
11  * DARPA CHATS research program.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. The names of the authors may not be used to endorse or promote
22  *    products derived from this software without specific prior written
23  *    permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  */
37 
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40 
41 #include "opt_ddb.h"
42 
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/devicestat.h>
46 #include <sys/kernel.h>
47 #include <sys/malloc.h>
48 #include <sys/bio.h>
49 #include <sys/sysctl.h>
50 #include <sys/proc.h>
51 #include <sys/kthread.h>
52 #include <sys/lock.h>
53 #include <sys/mutex.h>
54 #include <sys/errno.h>
55 #include <sys/sbuf.h>
56 #include <geom/geom.h>
57 #include <geom/geom_int.h>
58 #include <machine/stdarg.h>
59 
60 #ifdef DDB
61 #include <ddb/ddb.h>
62 #endif
63 
64 #ifdef KDB
65 #include <sys/kdb.h>
66 #endif
67 
68 struct class_list_head g_classes = LIST_HEAD_INITIALIZER(g_classes);
69 static struct g_tailq_head geoms = TAILQ_HEAD_INITIALIZER(geoms);
70 char *g_wait_event, *g_wait_up, *g_wait_down, *g_wait_sim;
71 
72 struct g_hh00 {
73 	struct g_class		*mp;
74 	struct g_provider	*pp;
75 	off_t			size;
76 	int			error;
77 	int			post;
78 };
79 
80 /*
81  * This event offers a new class a chance to taste all preexisting providers.
82  */
83 static void
84 g_load_class(void *arg, int flag)
85 {
86 	struct g_hh00 *hh;
87 	struct g_class *mp2, *mp;
88 	struct g_geom *gp;
89 	struct g_provider *pp;
90 
91 	g_topology_assert();
92 	if (flag == EV_CANCEL)	/* XXX: can't happen ? */
93 		return;
94 	if (g_shutdown)
95 		return;
96 
97 	hh = arg;
98 	mp = hh->mp;
99 	hh->error = 0;
100 	if (hh->post) {
101 		g_free(hh);
102 		hh = NULL;
103 	}
104 	g_trace(G_T_TOPOLOGY, "g_load_class(%s)", mp->name);
105 	KASSERT(mp->name != NULL && *mp->name != '\0',
106 	    ("GEOM class has no name"));
107 	LIST_FOREACH(mp2, &g_classes, class) {
108 		if (mp2 == mp) {
109 			printf("The GEOM class %s is already loaded.\n",
110 			    mp2->name);
111 			if (hh != NULL)
112 				hh->error = EEXIST;
113 			return;
114 		} else if (strcmp(mp2->name, mp->name) == 0) {
115 			printf("A GEOM class %s is already loaded.\n",
116 			    mp2->name);
117 			if (hh != NULL)
118 				hh->error = EEXIST;
119 			return;
120 		}
121 	}
122 
123 	LIST_INIT(&mp->geom);
124 	LIST_INSERT_HEAD(&g_classes, mp, class);
125 	if (mp->init != NULL)
126 		mp->init(mp);
127 	if (mp->taste == NULL)
128 		return;
129 	LIST_FOREACH(mp2, &g_classes, class) {
130 		if (mp == mp2)
131 			continue;
132 		LIST_FOREACH(gp, &mp2->geom, geom) {
133 			LIST_FOREACH(pp, &gp->provider, provider) {
134 				mp->taste(mp, pp, 0);
135 				g_topology_assert();
136 			}
137 		}
138 	}
139 }
140 
141 static int
142 g_unload_class(struct g_class *mp)
143 {
144 	struct g_geom *gp;
145 	struct g_provider *pp;
146 	struct g_consumer *cp;
147 	int error;
148 
149 	g_topology_lock();
150 	g_trace(G_T_TOPOLOGY, "g_unload_class(%s)", mp->name);
151 retry:
152 	G_VALID_CLASS(mp);
153 	LIST_FOREACH(gp, &mp->geom, geom) {
154 		/* We refuse to unload if anything is open */
155 		LIST_FOREACH(pp, &gp->provider, provider)
156 			if (pp->acr || pp->acw || pp->ace) {
157 				g_topology_unlock();
158 				return (EBUSY);
159 			}
160 		LIST_FOREACH(cp, &gp->consumer, consumer)
161 			if (cp->acr || cp->acw || cp->ace) {
162 				g_topology_unlock();
163 				return (EBUSY);
164 			}
165 		/* If the geom is withering, wait for it to finish. */
166 		if (gp->flags & G_GEOM_WITHER) {
167 			g_topology_sleep(mp, 1);
168 			goto retry;
169 		}
170 	}
171 
172 	/*
173 	 * We allow unloading if we have no geoms, or a class
174 	 * method we can use to get rid of them.
175 	 */
176 	if (!LIST_EMPTY(&mp->geom) && mp->destroy_geom == NULL) {
177 		g_topology_unlock();
178 		return (EOPNOTSUPP);
179 	}
180 
181 	/* Bar new entries */
182 	mp->taste = NULL;
183 	mp->config = NULL;
184 
185 	LIST_FOREACH(gp, &mp->geom, geom) {
186 		error = mp->destroy_geom(NULL, mp, gp);
187 		if (error != 0) {
188 			g_topology_unlock();
189 			return (error);
190 		}
191 	}
192 	/* Wait for withering to finish. */
193 	for (;;) {
194 		gp = LIST_FIRST(&mp->geom);
195 		if (gp == NULL)
196 			break;
197 		KASSERT(gp->flags & G_GEOM_WITHER,
198 		   ("Non-withering geom in class %s", mp->name));
199 		g_topology_sleep(mp, 1);
200 	}
201 	G_VALID_CLASS(mp);
202 	if (mp->fini != NULL)
203 		mp->fini(mp);
204 	LIST_REMOVE(mp, class);
205 	g_topology_unlock();
206 
207 	return (0);
208 }
209 
210 int
211 g_modevent(module_t mod, int type, void *data)
212 {
213 	struct g_hh00 *hh;
214 	int error;
215 	static int g_ignition;
216 	struct g_class *mp;
217 
218 	mp = data;
219 	if (mp->version != G_VERSION) {
220 		printf("GEOM class %s has Wrong version %x\n",
221 		    mp->name, mp->version);
222 		return (EINVAL);
223 	}
224 	if (!g_ignition) {
225 		g_ignition++;
226 		g_init();
227 	}
228 	error = EOPNOTSUPP;
229 	switch (type) {
230 	case MOD_LOAD:
231 		g_trace(G_T_TOPOLOGY, "g_modevent(%s, LOAD)", mp->name);
232 		hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
233 		hh->mp = mp;
234 		/*
235 		 * Once the system is not cold, MOD_LOAD calls will be
236 		 * from the userland and the g_event thread will be able
237 		 * to acknowledge their completion.
238 		 */
239 		if (cold) {
240 			hh->post = 1;
241 			error = g_post_event(g_load_class, hh, M_WAITOK, NULL);
242 		} else {
243 			error = g_waitfor_event(g_load_class, hh, M_WAITOK,
244 			    NULL);
245 			if (error == 0)
246 				error = hh->error;
247 			g_free(hh);
248 		}
249 		break;
250 	case MOD_UNLOAD:
251 		g_trace(G_T_TOPOLOGY, "g_modevent(%s, UNLOAD)", mp->name);
252 		error = g_unload_class(mp);
253 		if (error == 0) {
254 			KASSERT(LIST_EMPTY(&mp->geom),
255 			    ("Unloaded class (%s) still has geom", mp->name));
256 		}
257 		break;
258 	}
259 	return (error);
260 }
261 
262 static void
263 g_retaste_event(void *arg, int flag)
264 {
265 	struct g_class *mp, *mp2;
266 	struct g_geom *gp;
267 	struct g_hh00 *hh;
268 	struct g_provider *pp;
269 	struct g_consumer *cp;
270 
271 	g_topology_assert();
272 	if (flag == EV_CANCEL)  /* XXX: can't happen ? */
273 		return;
274 	if (g_shutdown || g_notaste)
275 		return;
276 
277 	hh = arg;
278 	mp = hh->mp;
279 	hh->error = 0;
280 	if (hh->post) {
281 		g_free(hh);
282 		hh = NULL;
283 	}
284 	g_trace(G_T_TOPOLOGY, "g_retaste(%s)", mp->name);
285 
286 	LIST_FOREACH(mp2, &g_classes, class) {
287 		LIST_FOREACH(gp, &mp2->geom, geom) {
288 			LIST_FOREACH(pp, &gp->provider, provider) {
289 				if (pp->acr || pp->acw || pp->ace)
290 					continue;
291 				LIST_FOREACH(cp, &pp->consumers, consumers) {
292 					if (cp->geom->class == mp &&
293 					    (cp->flags & G_CF_ORPHAN) == 0)
294 						break;
295 				}
296 				if (cp != NULL) {
297 					cp->flags |= G_CF_ORPHAN;
298 					g_wither_geom(cp->geom, ENXIO);
299 				}
300 				mp->taste(mp, pp, 0);
301 				g_topology_assert();
302 			}
303 		}
304 	}
305 }
306 
307 int
308 g_retaste(struct g_class *mp)
309 {
310 	struct g_hh00 *hh;
311 	int error;
312 
313 	if (mp->taste == NULL)
314 		return (EINVAL);
315 
316 	hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
317 	hh->mp = mp;
318 
319 	if (cold) {
320 		hh->post = 1;
321 		error = g_post_event(g_retaste_event, hh, M_WAITOK, NULL);
322 	} else {
323 		error = g_waitfor_event(g_retaste_event, hh, M_WAITOK, NULL);
324 		if (error == 0)
325 			error = hh->error;
326 		g_free(hh);
327 	}
328 
329 	return (error);
330 }
331 
332 struct g_geom *
333 g_new_geomf(struct g_class *mp, const char *fmt, ...)
334 {
335 	struct g_geom *gp;
336 	va_list ap;
337 	struct sbuf *sb;
338 
339 	g_topology_assert();
340 	G_VALID_CLASS(mp);
341 	sb = sbuf_new_auto();
342 	va_start(ap, fmt);
343 	sbuf_vprintf(sb, fmt, ap);
344 	va_end(ap);
345 	sbuf_finish(sb);
346 	gp = g_malloc(sizeof *gp, M_WAITOK | M_ZERO);
347 	gp->name = g_malloc(sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
348 	gp->class = mp;
349 	gp->rank = 1;
350 	LIST_INIT(&gp->consumer);
351 	LIST_INIT(&gp->provider);
352 	LIST_INIT(&gp->aliases);
353 	LIST_INSERT_HEAD(&mp->geom, gp, geom);
354 	TAILQ_INSERT_HEAD(&geoms, gp, geoms);
355 	strcpy(gp->name, sbuf_data(sb));
356 	sbuf_delete(sb);
357 	/* Fill in defaults from class */
358 	gp->start = mp->start;
359 	gp->spoiled = mp->spoiled;
360 	gp->attrchanged = mp->attrchanged;
361 	gp->providergone = mp->providergone;
362 	gp->dumpconf = mp->dumpconf;
363 	gp->access = mp->access;
364 	gp->orphan = mp->orphan;
365 	gp->ioctl = mp->ioctl;
366 	gp->resize = mp->resize;
367 	return (gp);
368 }
369 
370 void
371 g_destroy_geom(struct g_geom *gp)
372 {
373 	struct g_geom_alias *gap, *gaptmp;
374 
375 	g_topology_assert();
376 	G_VALID_GEOM(gp);
377 	g_trace(G_T_TOPOLOGY, "g_destroy_geom(%p(%s))", gp, gp->name);
378 	KASSERT(LIST_EMPTY(&gp->consumer),
379 	    ("g_destroy_geom(%s) with consumer(s) [%p]",
380 	    gp->name, LIST_FIRST(&gp->consumer)));
381 	KASSERT(LIST_EMPTY(&gp->provider),
382 	    ("g_destroy_geom(%s) with provider(s) [%p]",
383 	    gp->name, LIST_FIRST(&gp->provider)));
384 	g_cancel_event(gp);
385 	LIST_REMOVE(gp, geom);
386 	TAILQ_REMOVE(&geoms, gp, geoms);
387 	LIST_FOREACH_SAFE(gap, &gp->aliases, ga_next, gaptmp)
388 		g_free(gap);
389 	g_free(gp->name);
390 	g_free(gp);
391 }
392 
393 /*
394  * This function is called (repeatedly) until the geom has withered away.
395  */
396 void
397 g_wither_geom(struct g_geom *gp, int error)
398 {
399 	struct g_provider *pp;
400 
401 	g_topology_assert();
402 	G_VALID_GEOM(gp);
403 	g_trace(G_T_TOPOLOGY, "g_wither_geom(%p(%s))", gp, gp->name);
404 	if (!(gp->flags & G_GEOM_WITHER)) {
405 		gp->flags |= G_GEOM_WITHER;
406 		LIST_FOREACH(pp, &gp->provider, provider)
407 			if (!(pp->flags & G_PF_ORPHAN))
408 				g_orphan_provider(pp, error);
409 	}
410 	g_do_wither();
411 }
412 
413 /*
414  * Convenience function to destroy a particular provider.
415  */
416 void
417 g_wither_provider(struct g_provider *pp, int error)
418 {
419 
420 	pp->flags |= G_PF_WITHER;
421 	if (!(pp->flags & G_PF_ORPHAN))
422 		g_orphan_provider(pp, error);
423 }
424 
425 /*
426  * This function is called (repeatedly) until the has withered away.
427  */
428 void
429 g_wither_geom_close(struct g_geom *gp, int error)
430 {
431 	struct g_consumer *cp;
432 
433 	g_topology_assert();
434 	G_VALID_GEOM(gp);
435 	g_trace(G_T_TOPOLOGY, "g_wither_geom_close(%p(%s))", gp, gp->name);
436 	LIST_FOREACH(cp, &gp->consumer, consumer)
437 		if (cp->acr || cp->acw || cp->ace)
438 			g_access(cp, -cp->acr, -cp->acw, -cp->ace);
439 	g_wither_geom(gp, error);
440 }
441 
442 /*
443  * This function is called (repeatedly) until we cant wash away more
444  * withered bits at present.
445  */
446 void
447 g_wither_washer()
448 {
449 	struct g_class *mp;
450 	struct g_geom *gp, *gp2;
451 	struct g_provider *pp, *pp2;
452 	struct g_consumer *cp, *cp2;
453 
454 	g_topology_assert();
455 	LIST_FOREACH(mp, &g_classes, class) {
456 		LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
457 			LIST_FOREACH_SAFE(pp, &gp->provider, provider, pp2) {
458 				if (!(pp->flags & G_PF_WITHER))
459 					continue;
460 				if (LIST_EMPTY(&pp->consumers))
461 					g_destroy_provider(pp);
462 			}
463 			if (!(gp->flags & G_GEOM_WITHER))
464 				continue;
465 			LIST_FOREACH_SAFE(pp, &gp->provider, provider, pp2) {
466 				if (LIST_EMPTY(&pp->consumers))
467 					g_destroy_provider(pp);
468 			}
469 			LIST_FOREACH_SAFE(cp, &gp->consumer, consumer, cp2) {
470 				if (cp->acr || cp->acw || cp->ace)
471 					continue;
472 				if (cp->provider != NULL)
473 					g_detach(cp);
474 				g_destroy_consumer(cp);
475 			}
476 			if (LIST_EMPTY(&gp->provider) &&
477 			    LIST_EMPTY(&gp->consumer))
478 				g_destroy_geom(gp);
479 		}
480 	}
481 }
482 
483 struct g_consumer *
484 g_new_consumer(struct g_geom *gp)
485 {
486 	struct g_consumer *cp;
487 
488 	g_topology_assert();
489 	G_VALID_GEOM(gp);
490 	KASSERT(!(gp->flags & G_GEOM_WITHER),
491 	    ("g_new_consumer on WITHERing geom(%s) (class %s)",
492 	    gp->name, gp->class->name));
493 	KASSERT(gp->orphan != NULL,
494 	    ("g_new_consumer on geom(%s) (class %s) without orphan",
495 	    gp->name, gp->class->name));
496 
497 	cp = g_malloc(sizeof *cp, M_WAITOK | M_ZERO);
498 	cp->geom = gp;
499 	cp->stat = devstat_new_entry(cp, -1, 0, DEVSTAT_ALL_SUPPORTED,
500 	    DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
501 	LIST_INSERT_HEAD(&gp->consumer, cp, consumer);
502 	return(cp);
503 }
504 
505 void
506 g_destroy_consumer(struct g_consumer *cp)
507 {
508 	struct g_geom *gp;
509 
510 	g_topology_assert();
511 	G_VALID_CONSUMER(cp);
512 	g_trace(G_T_TOPOLOGY, "g_destroy_consumer(%p)", cp);
513 	KASSERT (cp->provider == NULL, ("g_destroy_consumer but attached"));
514 	KASSERT (cp->acr == 0, ("g_destroy_consumer with acr"));
515 	KASSERT (cp->acw == 0, ("g_destroy_consumer with acw"));
516 	KASSERT (cp->ace == 0, ("g_destroy_consumer with ace"));
517 	g_cancel_event(cp);
518 	gp = cp->geom;
519 	LIST_REMOVE(cp, consumer);
520 	devstat_remove_entry(cp->stat);
521 	g_free(cp);
522 	if (gp->flags & G_GEOM_WITHER)
523 		g_do_wither();
524 }
525 
526 static void
527 g_new_provider_event(void *arg, int flag)
528 {
529 	struct g_class *mp;
530 	struct g_provider *pp;
531 	struct g_consumer *cp, *next_cp;
532 
533 	g_topology_assert();
534 	if (flag == EV_CANCEL)
535 		return;
536 	if (g_shutdown)
537 		return;
538 	pp = arg;
539 	G_VALID_PROVIDER(pp);
540 	KASSERT(!(pp->flags & G_PF_WITHER),
541 	    ("g_new_provider_event but withered"));
542 	LIST_FOREACH_SAFE(cp, &pp->consumers, consumers, next_cp) {
543 		if ((cp->flags & G_CF_ORPHAN) == 0 &&
544 		    cp->geom->attrchanged != NULL)
545 			cp->geom->attrchanged(cp, "GEOM::media");
546 	}
547 	if (g_notaste)
548 		return;
549 	LIST_FOREACH(mp, &g_classes, class) {
550 		if (mp->taste == NULL)
551 			continue;
552 		LIST_FOREACH(cp, &pp->consumers, consumers)
553 			if (cp->geom->class == mp &&
554 			    (cp->flags & G_CF_ORPHAN) == 0)
555 				break;
556 		if (cp != NULL)
557 			continue;
558 		mp->taste(mp, pp, 0);
559 		g_topology_assert();
560 	}
561 }
562 
563 
564 struct g_provider *
565 g_new_providerf(struct g_geom *gp, const char *fmt, ...)
566 {
567 	struct g_provider *pp;
568 	struct sbuf *sb;
569 	va_list ap;
570 
571 	g_topology_assert();
572 	G_VALID_GEOM(gp);
573 	KASSERT(gp->access != NULL,
574 	    ("new provider on geom(%s) without ->access (class %s)",
575 	    gp->name, gp->class->name));
576 	KASSERT(gp->start != NULL,
577 	    ("new provider on geom(%s) without ->start (class %s)",
578 	    gp->name, gp->class->name));
579 	KASSERT(!(gp->flags & G_GEOM_WITHER),
580 	    ("new provider on WITHERing geom(%s) (class %s)",
581 	    gp->name, gp->class->name));
582 	sb = sbuf_new_auto();
583 	va_start(ap, fmt);
584 	sbuf_vprintf(sb, fmt, ap);
585 	va_end(ap);
586 	sbuf_finish(sb);
587 	pp = g_malloc(sizeof *pp + sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
588 	pp->name = (char *)(pp + 1);
589 	strcpy(pp->name, sbuf_data(sb));
590 	sbuf_delete(sb);
591 	LIST_INIT(&pp->consumers);
592 	pp->error = ENXIO;
593 	pp->geom = gp;
594 	pp->stat = devstat_new_entry(pp, -1, 0, DEVSTAT_ALL_SUPPORTED,
595 	    DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
596 	LIST_INSERT_HEAD(&gp->provider, pp, provider);
597 	g_post_event(g_new_provider_event, pp, M_WAITOK, pp, gp, NULL);
598 	return (pp);
599 }
600 
601 void
602 g_error_provider(struct g_provider *pp, int error)
603 {
604 
605 	/* G_VALID_PROVIDER(pp);  We may not have g_topology */
606 	pp->error = error;
607 }
608 
609 static void
610 g_resize_provider_event(void *arg, int flag)
611 {
612 	struct g_hh00 *hh;
613 	struct g_class *mp;
614 	struct g_geom *gp;
615 	struct g_provider *pp;
616 	struct g_consumer *cp, *cp2;
617 	off_t size;
618 
619 	g_topology_assert();
620 	if (g_shutdown)
621 		return;
622 
623 	hh = arg;
624 	pp = hh->pp;
625 	size = hh->size;
626 	g_free(hh);
627 
628 	G_VALID_PROVIDER(pp);
629 	KASSERT(!(pp->flags & G_PF_WITHER),
630 	    ("g_resize_provider_event but withered"));
631 	g_trace(G_T_TOPOLOGY, "g_resize_provider_event(%p)", pp);
632 
633 	LIST_FOREACH_SAFE(cp, &pp->consumers, consumers, cp2) {
634 		gp = cp->geom;
635 		if (gp->resize == NULL && size < pp->mediasize) {
636 			/*
637 			 * XXX: g_dev_orphan method does deferred destroying
638 			 * and it is possible, that other event could already
639 			 * call the orphan method. Check consumer's flags to
640 			 * do not schedule it twice.
641 			 */
642 			if (cp->flags & G_CF_ORPHAN)
643 				continue;
644 			cp->flags |= G_CF_ORPHAN;
645 			cp->geom->orphan(cp);
646 		}
647 	}
648 
649 	pp->mediasize = size;
650 
651 	LIST_FOREACH_SAFE(cp, &pp->consumers, consumers, cp2) {
652 		gp = cp->geom;
653 		if ((gp->flags & G_GEOM_WITHER) == 0 && gp->resize != NULL)
654 			gp->resize(cp);
655 	}
656 
657 	/*
658 	 * After resizing, the previously invalid GEOM class metadata
659 	 * might become valid.  This means we should retaste.
660 	 */
661 	LIST_FOREACH(mp, &g_classes, class) {
662 		if (mp->taste == NULL)
663 			continue;
664 		LIST_FOREACH(cp, &pp->consumers, consumers)
665 			if (cp->geom->class == mp &&
666 			    (cp->flags & G_CF_ORPHAN) == 0)
667 				break;
668 		if (cp != NULL)
669 			continue;
670 		mp->taste(mp, pp, 0);
671 		g_topology_assert();
672 	}
673 }
674 
675 void
676 g_resize_provider(struct g_provider *pp, off_t size)
677 {
678 	struct g_hh00 *hh;
679 
680 	G_VALID_PROVIDER(pp);
681 	if (pp->flags & G_PF_WITHER)
682 		return;
683 
684 	if (size == pp->mediasize)
685 		return;
686 
687 	hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
688 	hh->pp = pp;
689 	hh->size = size;
690 	g_post_event(g_resize_provider_event, hh, M_WAITOK, NULL);
691 }
692 
693 #ifndef	_PATH_DEV
694 #define	_PATH_DEV	"/dev/"
695 #endif
696 
697 struct g_provider *
698 g_provider_by_name(char const *arg)
699 {
700 	struct g_class *cp;
701 	struct g_geom *gp;
702 	struct g_provider *pp, *wpp;
703 
704 	if (strncmp(arg, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
705 		arg += sizeof(_PATH_DEV) - 1;
706 
707 	wpp = NULL;
708 	LIST_FOREACH(cp, &g_classes, class) {
709 		LIST_FOREACH(gp, &cp->geom, geom) {
710 			LIST_FOREACH(pp, &gp->provider, provider) {
711 				if (strcmp(arg, pp->name) != 0)
712 					continue;
713 				if ((gp->flags & G_GEOM_WITHER) == 0 &&
714 				    (pp->flags & G_PF_WITHER) == 0)
715 					return (pp);
716 				else
717 					wpp = pp;
718 			}
719 		}
720 	}
721 
722 	return (wpp);
723 }
724 
725 void
726 g_destroy_provider(struct g_provider *pp)
727 {
728 	struct g_geom *gp;
729 
730 	g_topology_assert();
731 	G_VALID_PROVIDER(pp);
732 	KASSERT(LIST_EMPTY(&pp->consumers),
733 	    ("g_destroy_provider but attached"));
734 	KASSERT (pp->acr == 0, ("g_destroy_provider with acr"));
735 	KASSERT (pp->acw == 0, ("g_destroy_provider with acw"));
736 	KASSERT (pp->ace == 0, ("g_destroy_provider with ace"));
737 	g_cancel_event(pp);
738 	LIST_REMOVE(pp, provider);
739 	gp = pp->geom;
740 	devstat_remove_entry(pp->stat);
741 	/*
742 	 * If a callback was provided, send notification that the provider
743 	 * is now gone.
744 	 */
745 	if (gp->providergone != NULL)
746 		gp->providergone(pp);
747 
748 	g_free(pp);
749 	if ((gp->flags & G_GEOM_WITHER))
750 		g_do_wither();
751 }
752 
753 /*
754  * We keep the "geoms" list sorted by topological order (== increasing
755  * numerical rank) at all times.
756  * When an attach is done, the attaching geoms rank is invalidated
757  * and it is moved to the tail of the list.
758  * All geoms later in the sequence has their ranks reevaluated in
759  * sequence.  If we cannot assign rank to a geom because it's
760  * prerequisites do not have rank, we move that element to the tail
761  * of the sequence with invalid rank as well.
762  * At some point we encounter our original geom and if we stil fail
763  * to assign it a rank, there must be a loop and we fail back to
764  * g_attach() which detach again and calls redo_rank again
765  * to fix up the damage.
766  * It would be much simpler code wise to do it recursively, but we
767  * can't risk that on the kernel stack.
768  */
769 
770 static int
771 redo_rank(struct g_geom *gp)
772 {
773 	struct g_consumer *cp;
774 	struct g_geom *gp1, *gp2;
775 	int n, m;
776 
777 	g_topology_assert();
778 	G_VALID_GEOM(gp);
779 
780 	/* Invalidate this geoms rank and move it to the tail */
781 	gp1 = TAILQ_NEXT(gp, geoms);
782 	if (gp1 != NULL) {
783 		gp->rank = 0;
784 		TAILQ_REMOVE(&geoms, gp, geoms);
785 		TAILQ_INSERT_TAIL(&geoms, gp, geoms);
786 	} else {
787 		gp1 = gp;
788 	}
789 
790 	/* re-rank the rest of the sequence */
791 	for (; gp1 != NULL; gp1 = gp2) {
792 		gp1->rank = 0;
793 		m = 1;
794 		LIST_FOREACH(cp, &gp1->consumer, consumer) {
795 			if (cp->provider == NULL)
796 				continue;
797 			n = cp->provider->geom->rank;
798 			if (n == 0) {
799 				m = 0;
800 				break;
801 			} else if (n >= m)
802 				m = n + 1;
803 		}
804 		gp1->rank = m;
805 		gp2 = TAILQ_NEXT(gp1, geoms);
806 
807 		/* got a rank, moving on */
808 		if (m != 0)
809 			continue;
810 
811 		/* no rank to original geom means loop */
812 		if (gp == gp1)
813 			return (ELOOP);
814 
815 		/* no rank, put it at the end move on */
816 		TAILQ_REMOVE(&geoms, gp1, geoms);
817 		TAILQ_INSERT_TAIL(&geoms, gp1, geoms);
818 	}
819 	return (0);
820 }
821 
822 int
823 g_attach(struct g_consumer *cp, struct g_provider *pp)
824 {
825 	int error;
826 
827 	g_topology_assert();
828 	G_VALID_CONSUMER(cp);
829 	G_VALID_PROVIDER(pp);
830 	g_trace(G_T_TOPOLOGY, "g_attach(%p, %p)", cp, pp);
831 	KASSERT(cp->provider == NULL, ("attach but attached"));
832 	cp->provider = pp;
833 	cp->flags &= ~G_CF_ORPHAN;
834 	LIST_INSERT_HEAD(&pp->consumers, cp, consumers);
835 	error = redo_rank(cp->geom);
836 	if (error) {
837 		LIST_REMOVE(cp, consumers);
838 		cp->provider = NULL;
839 		redo_rank(cp->geom);
840 	}
841 	return (error);
842 }
843 
844 void
845 g_detach(struct g_consumer *cp)
846 {
847 	struct g_provider *pp;
848 
849 	g_topology_assert();
850 	G_VALID_CONSUMER(cp);
851 	g_trace(G_T_TOPOLOGY, "g_detach(%p)", cp);
852 	KASSERT(cp->provider != NULL, ("detach but not attached"));
853 	KASSERT(cp->acr == 0, ("detach but nonzero acr"));
854 	KASSERT(cp->acw == 0, ("detach but nonzero acw"));
855 	KASSERT(cp->ace == 0, ("detach but nonzero ace"));
856 	KASSERT(cp->nstart == cp->nend,
857 	    ("detach with active requests"));
858 	pp = cp->provider;
859 	LIST_REMOVE(cp, consumers);
860 	cp->provider = NULL;
861 	if ((cp->geom->flags & G_GEOM_WITHER) ||
862 	    (pp->geom->flags & G_GEOM_WITHER) ||
863 	    (pp->flags & G_PF_WITHER))
864 		g_do_wither();
865 	redo_rank(cp->geom);
866 }
867 
868 /*
869  * g_access()
870  *
871  * Access-check with delta values.  The question asked is "can provider
872  * "cp" change the access counters by the relative amounts dc[rwe] ?"
873  */
874 
875 int
876 g_access(struct g_consumer *cp, int dcr, int dcw, int dce)
877 {
878 	struct g_provider *pp;
879 	struct g_geom *gp;
880 	int pw, pe;
881 #ifdef INVARIANTS
882 	int sr, sw, se;
883 #endif
884 	int error;
885 
886 	g_topology_assert();
887 	G_VALID_CONSUMER(cp);
888 	pp = cp->provider;
889 	KASSERT(pp != NULL, ("access but not attached"));
890 	G_VALID_PROVIDER(pp);
891 	gp = pp->geom;
892 
893 	g_trace(G_T_ACCESS, "g_access(%p(%s), %d, %d, %d)",
894 	    cp, pp->name, dcr, dcw, dce);
895 
896 	KASSERT(cp->acr + dcr >= 0, ("access resulting in negative acr"));
897 	KASSERT(cp->acw + dcw >= 0, ("access resulting in negative acw"));
898 	KASSERT(cp->ace + dce >= 0, ("access resulting in negative ace"));
899 	KASSERT(dcr != 0 || dcw != 0 || dce != 0, ("NOP access request"));
900 	KASSERT(gp->access != NULL, ("NULL geom->access"));
901 
902 	/*
903 	 * If our class cares about being spoiled, and we have been, we
904 	 * are probably just ahead of the event telling us that.  Fail
905 	 * now rather than having to unravel this later.
906 	 */
907 	if (cp->geom->spoiled != NULL && (cp->flags & G_CF_SPOILED) &&
908 	    (dcr > 0 || dcw > 0 || dce > 0))
909 		return (ENXIO);
910 
911 	/*
912 	 * A number of GEOM classes either need to perform an I/O on the first
913 	 * open or to acquire a different subsystem's lock.  To do that they
914 	 * may have to drop the topology lock.
915 	 * Other GEOM classes perform special actions when opening a lower rank
916 	 * geom for the first time.  As a result, more than one thread may
917 	 * end up performing the special actions.
918 	 * So, we prevent concurrent "first" opens by marking the consumer with
919 	 * special flag.
920 	 *
921 	 * Note that if the geom's access method never drops the topology lock,
922 	 * then we will never see G_GEOM_IN_ACCESS here.
923 	 */
924 	while ((gp->flags & G_GEOM_IN_ACCESS) != 0) {
925 		g_trace(G_T_ACCESS,
926 		    "%s: race on geom %s via provider %s and consumer of %s",
927 		    __func__, gp->name, pp->name, cp->geom->name);
928 		gp->flags |= G_GEOM_ACCESS_WAIT;
929 		g_topology_sleep(gp, 0);
930 	}
931 
932 	/*
933 	 * Figure out what counts the provider would have had, if this
934 	 * consumer had (r0w0e0) at this time.
935 	 */
936 	pw = pp->acw - cp->acw;
937 	pe = pp->ace - cp->ace;
938 
939 	g_trace(G_T_ACCESS,
940     "open delta:[r%dw%de%d] old:[r%dw%de%d] provider:[r%dw%de%d] %p(%s)",
941 	    dcr, dcw, dce,
942 	    cp->acr, cp->acw, cp->ace,
943 	    pp->acr, pp->acw, pp->ace,
944 	    pp, pp->name);
945 
946 	/* If foot-shooting is enabled, any open on rank#1 is OK */
947 	if ((g_debugflags & 16) && gp->rank == 1)
948 		;
949 	/* If we try exclusive but already write: fail */
950 	else if (dce > 0 && pw > 0)
951 		return (EPERM);
952 	/* If we try write but already exclusive: fail */
953 	else if (dcw > 0 && pe > 0)
954 		return (EPERM);
955 	/* If we try to open more but provider is error'ed: fail */
956 	else if ((dcr > 0 || dcw > 0 || dce > 0) && pp->error != 0) {
957 		printf("%s(%d): provider %s has error %d set\n",
958 		    __func__, __LINE__, pp->name, pp->error);
959 		return (pp->error);
960 	}
961 
962 	/* Ok then... */
963 
964 #ifdef INVARIANTS
965 	sr = cp->acr;
966 	sw = cp->acw;
967 	se = cp->ace;
968 #endif
969 	gp->flags |= G_GEOM_IN_ACCESS;
970 	error = gp->access(pp, dcr, dcw, dce);
971 	KASSERT(dcr > 0 || dcw > 0 || dce > 0 || error == 0,
972 	    ("Geom provider %s::%s dcr=%d dcw=%d dce=%d error=%d failed "
973 	    "closing ->access()", gp->class->name, pp->name, dcr, dcw,
974 	    dce, error));
975 
976 	g_topology_assert();
977 	gp->flags &= ~G_GEOM_IN_ACCESS;
978 	KASSERT(cp->acr == sr && cp->acw == sw && cp->ace == se,
979 	    ("Access counts changed during geom->access"));
980 	if ((gp->flags & G_GEOM_ACCESS_WAIT) != 0) {
981 		gp->flags &= ~G_GEOM_ACCESS_WAIT;
982 		wakeup(gp);
983 	}
984 
985 	if (!error) {
986 		/*
987 		 * If we open first write, spoil any partner consumers.
988 		 * If we close last write and provider is not errored,
989 		 * trigger re-taste.
990 		 */
991 		if (pp->acw == 0 && dcw != 0)
992 			g_spoil(pp, cp);
993 		else if (pp->acw != 0 && pp->acw == -dcw && pp->error == 0 &&
994 		    !(gp->flags & G_GEOM_WITHER))
995 			g_post_event(g_new_provider_event, pp, M_WAITOK,
996 			    pp, NULL);
997 
998 		pp->acr += dcr;
999 		pp->acw += dcw;
1000 		pp->ace += dce;
1001 		cp->acr += dcr;
1002 		cp->acw += dcw;
1003 		cp->ace += dce;
1004 		if (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)
1005 			KASSERT(pp->sectorsize > 0,
1006 			    ("Provider %s lacks sectorsize", pp->name));
1007 		if ((cp->geom->flags & G_GEOM_WITHER) &&
1008 		    cp->acr == 0 && cp->acw == 0 && cp->ace == 0)
1009 			g_do_wither();
1010 	}
1011 	return (error);
1012 }
1013 
1014 int
1015 g_handleattr_int(struct bio *bp, const char *attribute, int val)
1016 {
1017 
1018 	return (g_handleattr(bp, attribute, &val, sizeof val));
1019 }
1020 
1021 int
1022 g_handleattr_uint16_t(struct bio *bp, const char *attribute, uint16_t val)
1023 {
1024 
1025 	return (g_handleattr(bp, attribute, &val, sizeof val));
1026 }
1027 
1028 int
1029 g_handleattr_off_t(struct bio *bp, const char *attribute, off_t val)
1030 {
1031 
1032 	return (g_handleattr(bp, attribute, &val, sizeof val));
1033 }
1034 
1035 int
1036 g_handleattr_str(struct bio *bp, const char *attribute, const char *str)
1037 {
1038 
1039 	return (g_handleattr(bp, attribute, str, 0));
1040 }
1041 
1042 int
1043 g_handleattr(struct bio *bp, const char *attribute, const void *val, int len)
1044 {
1045 	int error = 0;
1046 
1047 	if (strcmp(bp->bio_attribute, attribute))
1048 		return (0);
1049 	if (len == 0) {
1050 		bzero(bp->bio_data, bp->bio_length);
1051 		if (strlcpy(bp->bio_data, val, bp->bio_length) >=
1052 		    bp->bio_length) {
1053 			printf("%s: %s %s bio_length %jd strlen %zu -> EFAULT\n",
1054 			    __func__, bp->bio_to->name, attribute,
1055 			    (intmax_t)bp->bio_length, strlen(val));
1056 			error = EFAULT;
1057 		}
1058 	} else if (bp->bio_length == len) {
1059 		bcopy(val, bp->bio_data, len);
1060 	} else {
1061 		printf("%s: %s %s bio_length %jd len %d -> EFAULT\n", __func__,
1062 		    bp->bio_to->name, attribute, (intmax_t)bp->bio_length, len);
1063 		error = EFAULT;
1064 	}
1065 	if (error == 0)
1066 		bp->bio_completed = bp->bio_length;
1067 	g_io_deliver(bp, error);
1068 	return (1);
1069 }
1070 
1071 int
1072 g_std_access(struct g_provider *pp,
1073 	int dr __unused, int dw __unused, int de __unused)
1074 {
1075 
1076 	g_topology_assert();
1077 	G_VALID_PROVIDER(pp);
1078         return (0);
1079 }
1080 
1081 void
1082 g_std_done(struct bio *bp)
1083 {
1084 	struct bio *bp2;
1085 
1086 	bp2 = bp->bio_parent;
1087 	if (bp2->bio_error == 0)
1088 		bp2->bio_error = bp->bio_error;
1089 	bp2->bio_completed += bp->bio_completed;
1090 	g_destroy_bio(bp);
1091 	bp2->bio_inbed++;
1092 	if (bp2->bio_children == bp2->bio_inbed)
1093 		g_io_deliver(bp2, bp2->bio_error);
1094 }
1095 
1096 /* XXX: maybe this is only g_slice_spoiled */
1097 
1098 void
1099 g_std_spoiled(struct g_consumer *cp)
1100 {
1101 	struct g_geom *gp;
1102 	struct g_provider *pp;
1103 
1104 	g_topology_assert();
1105 	G_VALID_CONSUMER(cp);
1106 	g_trace(G_T_TOPOLOGY, "g_std_spoiled(%p)", cp);
1107 	cp->flags |= G_CF_ORPHAN;
1108 	g_detach(cp);
1109 	gp = cp->geom;
1110 	LIST_FOREACH(pp, &gp->provider, provider)
1111 		g_orphan_provider(pp, ENXIO);
1112 	g_destroy_consumer(cp);
1113 	if (LIST_EMPTY(&gp->provider) && LIST_EMPTY(&gp->consumer))
1114 		g_destroy_geom(gp);
1115 	else
1116 		gp->flags |= G_GEOM_WITHER;
1117 }
1118 
1119 /*
1120  * Spoiling happens when a provider is opened for writing, but consumers
1121  * which are configured by in-band data are attached (slicers for instance).
1122  * Since the write might potentially change the in-band data, such consumers
1123  * need to re-evaluate their existence after the writing session closes.
1124  * We do this by (offering to) tear them down when the open for write happens
1125  * in return for a re-taste when it closes again.
1126  * Together with the fact that such consumers grab an 'e' bit whenever they
1127  * are open, regardless of mode, this ends up DTRT.
1128  */
1129 
1130 static void
1131 g_spoil_event(void *arg, int flag)
1132 {
1133 	struct g_provider *pp;
1134 	struct g_consumer *cp, *cp2;
1135 
1136 	g_topology_assert();
1137 	if (flag == EV_CANCEL)
1138 		return;
1139 	pp = arg;
1140 	G_VALID_PROVIDER(pp);
1141 	g_trace(G_T_TOPOLOGY, "%s %p(%s:%s:%s)", __func__, pp,
1142 	    pp->geom->class->name, pp->geom->name, pp->name);
1143 	for (cp = LIST_FIRST(&pp->consumers); cp != NULL; cp = cp2) {
1144 		cp2 = LIST_NEXT(cp, consumers);
1145 		if ((cp->flags & G_CF_SPOILED) == 0)
1146 			continue;
1147 		cp->flags &= ~G_CF_SPOILED;
1148 		if (cp->geom->spoiled == NULL)
1149 			continue;
1150 		cp->geom->spoiled(cp);
1151 		g_topology_assert();
1152 	}
1153 }
1154 
1155 void
1156 g_spoil(struct g_provider *pp, struct g_consumer *cp)
1157 {
1158 	struct g_consumer *cp2;
1159 
1160 	g_topology_assert();
1161 	G_VALID_PROVIDER(pp);
1162 	G_VALID_CONSUMER(cp);
1163 
1164 	LIST_FOREACH(cp2, &pp->consumers, consumers) {
1165 		if (cp2 == cp)
1166 			continue;
1167 /*
1168 		KASSERT(cp2->acr == 0, ("spoiling cp->acr = %d", cp2->acr));
1169 		KASSERT(cp2->acw == 0, ("spoiling cp->acw = %d", cp2->acw));
1170 */
1171 		KASSERT(cp2->ace == 0, ("spoiling cp->ace = %d", cp2->ace));
1172 		cp2->flags |= G_CF_SPOILED;
1173 	}
1174 	g_post_event(g_spoil_event, pp, M_WAITOK, pp, NULL);
1175 }
1176 
1177 static void
1178 g_media_changed_event(void *arg, int flag)
1179 {
1180 	struct g_provider *pp;
1181 	int retaste;
1182 
1183 	g_topology_assert();
1184 	if (flag == EV_CANCEL)
1185 		return;
1186 	pp = arg;
1187 	G_VALID_PROVIDER(pp);
1188 
1189 	/*
1190 	 * If provider was not open for writing, queue retaste after spoiling.
1191 	 * If it was, retaste will happen automatically on close.
1192 	 */
1193 	retaste = (pp->acw == 0 && pp->error == 0 &&
1194 	    !(pp->geom->flags & G_GEOM_WITHER));
1195 	g_spoil_event(arg, flag);
1196 	if (retaste)
1197 		g_post_event(g_new_provider_event, pp, M_WAITOK, pp, NULL);
1198 }
1199 
1200 int
1201 g_media_changed(struct g_provider *pp, int flag)
1202 {
1203 	struct g_consumer *cp;
1204 
1205 	LIST_FOREACH(cp, &pp->consumers, consumers)
1206 		cp->flags |= G_CF_SPOILED;
1207 	return (g_post_event(g_media_changed_event, pp, flag, pp, NULL));
1208 }
1209 
1210 int
1211 g_media_gone(struct g_provider *pp, int flag)
1212 {
1213 	struct g_consumer *cp;
1214 
1215 	LIST_FOREACH(cp, &pp->consumers, consumers)
1216 		cp->flags |= G_CF_SPOILED;
1217 	return (g_post_event(g_spoil_event, pp, flag, pp, NULL));
1218 }
1219 
1220 int
1221 g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len)
1222 {
1223 	int error, i;
1224 
1225 	i = len;
1226 	error = g_io_getattr(attr, cp, &i, var);
1227 	if (error)
1228 		return (error);
1229 	if (i != len)
1230 		return (EINVAL);
1231 	return (0);
1232 }
1233 
1234 static int
1235 g_get_device_prefix_len(const char *name)
1236 {
1237 	int len;
1238 
1239 	if (strncmp(name, "ada", 3) == 0)
1240 		len = 3;
1241 	else if (strncmp(name, "ad", 2) == 0)
1242 		len = 2;
1243 	else
1244 		return (0);
1245 	if (name[len] < '0' || name[len] > '9')
1246 		return (0);
1247 	do {
1248 		len++;
1249 	} while (name[len] >= '0' && name[len] <= '9');
1250 	return (len);
1251 }
1252 
1253 int
1254 g_compare_names(const char *namea, const char *nameb)
1255 {
1256 	int deva, devb;
1257 
1258 	if (strcmp(namea, nameb) == 0)
1259 		return (1);
1260 	deva = g_get_device_prefix_len(namea);
1261 	if (deva == 0)
1262 		return (0);
1263 	devb = g_get_device_prefix_len(nameb);
1264 	if (devb == 0)
1265 		return (0);
1266 	if (strcmp(namea + deva, nameb + devb) == 0)
1267 		return (1);
1268 	return (0);
1269 }
1270 
1271 void
1272 g_geom_add_alias(struct g_geom *gp, const char *alias)
1273 {
1274 	struct g_geom_alias *gap;
1275 
1276 	gap = (struct g_geom_alias *)g_malloc(
1277 		sizeof(struct g_geom_alias) + strlen(alias) + 1, M_WAITOK);
1278 	strcpy((char *)(gap + 1), alias);
1279 	gap->ga_alias = (const char *)(gap + 1);
1280 	LIST_INSERT_HEAD(&gp->aliases, gap, ga_next);
1281 }
1282 
1283 #if defined(DIAGNOSTIC) || defined(DDB)
1284 /*
1285  * This function walks the mesh and returns a non-zero integer if it
1286  * finds the argument pointer is an object. The return value indicates
1287  * which type of object it is believed to be. If topology is not locked,
1288  * this function is potentially dangerous, but we don't assert that the
1289  * topology lock is held when called from debugger.
1290  */
1291 int
1292 g_valid_obj(void const *ptr)
1293 {
1294 	struct g_class *mp;
1295 	struct g_geom *gp;
1296 	struct g_consumer *cp;
1297 	struct g_provider *pp;
1298 
1299 #ifdef KDB
1300 	if (kdb_active == 0)
1301 #endif
1302 		g_topology_assert();
1303 
1304 	LIST_FOREACH(mp, &g_classes, class) {
1305 		if (ptr == mp)
1306 			return (1);
1307 		LIST_FOREACH(gp, &mp->geom, geom) {
1308 			if (ptr == gp)
1309 				return (2);
1310 			LIST_FOREACH(cp, &gp->consumer, consumer)
1311 				if (ptr == cp)
1312 					return (3);
1313 			LIST_FOREACH(pp, &gp->provider, provider)
1314 				if (ptr == pp)
1315 					return (4);
1316 		}
1317 	}
1318 	return(0);
1319 }
1320 #endif
1321 
1322 #ifdef DDB
1323 
1324 #define	gprintf(...)	do {						\
1325 	db_printf("%*s", indent, "");					\
1326 	db_printf(__VA_ARGS__);						\
1327 } while (0)
1328 #define	gprintln(...)	do {						\
1329 	gprintf(__VA_ARGS__);						\
1330 	db_printf("\n");						\
1331 } while (0)
1332 
1333 #define	ADDFLAG(obj, flag, sflag)	do {				\
1334 	if ((obj)->flags & (flag)) {					\
1335 		if (comma)						\
1336 			strlcat(str, ",", size);			\
1337 		strlcat(str, (sflag), size);				\
1338 		comma = 1;						\
1339 	}								\
1340 } while (0)
1341 
1342 static char *
1343 provider_flags_to_string(struct g_provider *pp, char *str, size_t size)
1344 {
1345 	int comma = 0;
1346 
1347 	bzero(str, size);
1348 	if (pp->flags == 0) {
1349 		strlcpy(str, "NONE", size);
1350 		return (str);
1351 	}
1352 	ADDFLAG(pp, G_PF_WITHER, "G_PF_WITHER");
1353 	ADDFLAG(pp, G_PF_ORPHAN, "G_PF_ORPHAN");
1354 	return (str);
1355 }
1356 
1357 static char *
1358 geom_flags_to_string(struct g_geom *gp, char *str, size_t size)
1359 {
1360 	int comma = 0;
1361 
1362 	bzero(str, size);
1363 	if (gp->flags == 0) {
1364 		strlcpy(str, "NONE", size);
1365 		return (str);
1366 	}
1367 	ADDFLAG(gp, G_GEOM_WITHER, "G_GEOM_WITHER");
1368 	return (str);
1369 }
1370 static void
1371 db_show_geom_consumer(int indent, struct g_consumer *cp)
1372 {
1373 
1374 	if (indent == 0) {
1375 		gprintln("consumer: %p", cp);
1376 		gprintln("  class:    %s (%p)", cp->geom->class->name,
1377 		    cp->geom->class);
1378 		gprintln("  geom:     %s (%p)", cp->geom->name, cp->geom);
1379 		if (cp->provider == NULL)
1380 			gprintln("  provider: none");
1381 		else {
1382 			gprintln("  provider: %s (%p)", cp->provider->name,
1383 			    cp->provider);
1384 		}
1385 		gprintln("  access:   r%dw%de%d", cp->acr, cp->acw, cp->ace);
1386 		gprintln("  flags:    0x%04x", cp->flags);
1387 		gprintln("  nstart:   %u", cp->nstart);
1388 		gprintln("  nend:     %u", cp->nend);
1389 	} else {
1390 		gprintf("consumer: %p (%s), access=r%dw%de%d", cp,
1391 		    cp->provider != NULL ? cp->provider->name : "none",
1392 		    cp->acr, cp->acw, cp->ace);
1393 		if (cp->flags)
1394 			db_printf(", flags=0x%04x", cp->flags);
1395 		db_printf("\n");
1396 	}
1397 }
1398 
1399 static void
1400 db_show_geom_provider(int indent, struct g_provider *pp)
1401 {
1402 	struct g_consumer *cp;
1403 	char flags[64];
1404 
1405 	if (indent == 0) {
1406 		gprintln("provider: %s (%p)", pp->name, pp);
1407 		gprintln("  class:        %s (%p)", pp->geom->class->name,
1408 		    pp->geom->class);
1409 		gprintln("  geom:         %s (%p)", pp->geom->name, pp->geom);
1410 		gprintln("  mediasize:    %jd", (intmax_t)pp->mediasize);
1411 		gprintln("  sectorsize:   %u", pp->sectorsize);
1412 		gprintln("  stripesize:   %u", pp->stripesize);
1413 		gprintln("  stripeoffset: %u", pp->stripeoffset);
1414 		gprintln("  access:       r%dw%de%d", pp->acr, pp->acw,
1415 		    pp->ace);
1416 		gprintln("  flags:        %s (0x%04x)",
1417 		    provider_flags_to_string(pp, flags, sizeof(flags)),
1418 		    pp->flags);
1419 		gprintln("  error:        %d", pp->error);
1420 		gprintln("  nstart:       %u", pp->nstart);
1421 		gprintln("  nend:         %u", pp->nend);
1422 		if (LIST_EMPTY(&pp->consumers))
1423 			gprintln("  consumers:    none");
1424 	} else {
1425 		gprintf("provider: %s (%p), access=r%dw%de%d",
1426 		    pp->name, pp, pp->acr, pp->acw, pp->ace);
1427 		if (pp->flags != 0) {
1428 			db_printf(", flags=%s (0x%04x)",
1429 			    provider_flags_to_string(pp, flags, sizeof(flags)),
1430 			    pp->flags);
1431 		}
1432 		db_printf("\n");
1433 	}
1434 	if (!LIST_EMPTY(&pp->consumers)) {
1435 		LIST_FOREACH(cp, &pp->consumers, consumers) {
1436 			db_show_geom_consumer(indent + 2, cp);
1437 			if (db_pager_quit)
1438 				break;
1439 		}
1440 	}
1441 }
1442 
1443 static void
1444 db_show_geom_geom(int indent, struct g_geom *gp)
1445 {
1446 	struct g_provider *pp;
1447 	struct g_consumer *cp;
1448 	char flags[64];
1449 
1450 	if (indent == 0) {
1451 		gprintln("geom: %s (%p)", gp->name, gp);
1452 		gprintln("  class:     %s (%p)", gp->class->name, gp->class);
1453 		gprintln("  flags:     %s (0x%04x)",
1454 		    geom_flags_to_string(gp, flags, sizeof(flags)), gp->flags);
1455 		gprintln("  rank:      %d", gp->rank);
1456 		if (LIST_EMPTY(&gp->provider))
1457 			gprintln("  providers: none");
1458 		if (LIST_EMPTY(&gp->consumer))
1459 			gprintln("  consumers: none");
1460 	} else {
1461 		gprintf("geom: %s (%p), rank=%d", gp->name, gp, gp->rank);
1462 		if (gp->flags != 0) {
1463 			db_printf(", flags=%s (0x%04x)",
1464 			    geom_flags_to_string(gp, flags, sizeof(flags)),
1465 			    gp->flags);
1466 		}
1467 		db_printf("\n");
1468 	}
1469 	if (!LIST_EMPTY(&gp->provider)) {
1470 		LIST_FOREACH(pp, &gp->provider, provider) {
1471 			db_show_geom_provider(indent + 2, pp);
1472 			if (db_pager_quit)
1473 				break;
1474 		}
1475 	}
1476 	if (!LIST_EMPTY(&gp->consumer)) {
1477 		LIST_FOREACH(cp, &gp->consumer, consumer) {
1478 			db_show_geom_consumer(indent + 2, cp);
1479 			if (db_pager_quit)
1480 				break;
1481 		}
1482 	}
1483 }
1484 
1485 static void
1486 db_show_geom_class(struct g_class *mp)
1487 {
1488 	struct g_geom *gp;
1489 
1490 	db_printf("class: %s (%p)\n", mp->name, mp);
1491 	LIST_FOREACH(gp, &mp->geom, geom) {
1492 		db_show_geom_geom(2, gp);
1493 		if (db_pager_quit)
1494 			break;
1495 	}
1496 }
1497 
1498 /*
1499  * Print the GEOM topology or the given object.
1500  */
1501 DB_SHOW_COMMAND(geom, db_show_geom)
1502 {
1503 	struct g_class *mp;
1504 
1505 	if (!have_addr) {
1506 		/* No address given, print the entire topology. */
1507 		LIST_FOREACH(mp, &g_classes, class) {
1508 			db_show_geom_class(mp);
1509 			db_printf("\n");
1510 			if (db_pager_quit)
1511 				break;
1512 		}
1513 	} else {
1514 		switch (g_valid_obj((void *)addr)) {
1515 		case 1:
1516 			db_show_geom_class((struct g_class *)addr);
1517 			break;
1518 		case 2:
1519 			db_show_geom_geom(0, (struct g_geom *)addr);
1520 			break;
1521 		case 3:
1522 			db_show_geom_consumer(0, (struct g_consumer *)addr);
1523 			break;
1524 		case 4:
1525 			db_show_geom_provider(0, (struct g_provider *)addr);
1526 			break;
1527 		default:
1528 			db_printf("Not a GEOM object.\n");
1529 			break;
1530 		}
1531 	}
1532 }
1533 
1534 static void
1535 db_print_bio_cmd(struct bio *bp)
1536 {
1537 	db_printf("  cmd: ");
1538 	switch (bp->bio_cmd) {
1539 	case BIO_READ: db_printf("BIO_READ"); break;
1540 	case BIO_WRITE: db_printf("BIO_WRITE"); break;
1541 	case BIO_DELETE: db_printf("BIO_DELETE"); break;
1542 	case BIO_GETATTR: db_printf("BIO_GETATTR"); break;
1543 	case BIO_FLUSH: db_printf("BIO_FLUSH"); break;
1544 	case BIO_CMD0: db_printf("BIO_CMD0"); break;
1545 	case BIO_CMD1: db_printf("BIO_CMD1"); break;
1546 	case BIO_CMD2: db_printf("BIO_CMD2"); break;
1547 	case BIO_ZONE: db_printf("BIO_ZONE"); break;
1548 	default: db_printf("UNKNOWN"); break;
1549 	}
1550 	db_printf("\n");
1551 }
1552 
1553 static void
1554 db_print_bio_flags(struct bio *bp)
1555 {
1556 	int comma;
1557 
1558 	comma = 0;
1559 	db_printf("  flags: ");
1560 	if (bp->bio_flags & BIO_ERROR) {
1561 		db_printf("BIO_ERROR");
1562 		comma = 1;
1563 	}
1564 	if (bp->bio_flags & BIO_DONE) {
1565 		db_printf("%sBIO_DONE", (comma ? ", " : ""));
1566 		comma = 1;
1567 	}
1568 	if (bp->bio_flags & BIO_ONQUEUE)
1569 		db_printf("%sBIO_ONQUEUE", (comma ? ", " : ""));
1570 	db_printf("\n");
1571 }
1572 
1573 /*
1574  * Print useful information in a BIO
1575  */
1576 DB_SHOW_COMMAND(bio, db_show_bio)
1577 {
1578 	struct bio *bp;
1579 
1580 	if (have_addr) {
1581 		bp = (struct bio *)addr;
1582 		db_printf("BIO %p\n", bp);
1583 		db_print_bio_cmd(bp);
1584 		db_print_bio_flags(bp);
1585 		db_printf("  cflags: 0x%hx\n", bp->bio_cflags);
1586 		db_printf("  pflags: 0x%hx\n", bp->bio_pflags);
1587 		db_printf("  offset: %jd\n", (intmax_t)bp->bio_offset);
1588 		db_printf("  length: %jd\n", (intmax_t)bp->bio_length);
1589 		db_printf("  bcount: %ld\n", bp->bio_bcount);
1590 		db_printf("  resid: %ld\n", bp->bio_resid);
1591 		db_printf("  completed: %jd\n", (intmax_t)bp->bio_completed);
1592 		db_printf("  children: %u\n", bp->bio_children);
1593 		db_printf("  inbed: %u\n", bp->bio_inbed);
1594 		db_printf("  error: %d\n", bp->bio_error);
1595 		db_printf("  parent: %p\n", bp->bio_parent);
1596 		db_printf("  driver1: %p\n", bp->bio_driver1);
1597 		db_printf("  driver2: %p\n", bp->bio_driver2);
1598 		db_printf("  caller1: %p\n", bp->bio_caller1);
1599 		db_printf("  caller2: %p\n", bp->bio_caller2);
1600 		db_printf("  bio_from: %p\n", bp->bio_from);
1601 		db_printf("  bio_to: %p\n", bp->bio_to);
1602 
1603 #if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING)
1604 		db_printf("  bio_track_bp: %p\n", bp->bio_track_bp);
1605 #endif
1606 	}
1607 }
1608 
1609 #undef	gprintf
1610 #undef	gprintln
1611 #undef	ADDFLAG
1612 
1613 #endif	/* DDB */
1614