xref: /freebsd/sys/geom/geom_subr.c (revision 6132212808e8dccedc9e5d85fea4390c2f38059a)
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 <sys/sdt.h>
57 #include <geom/geom.h>
58 #include <geom/geom_dbg.h>
59 #include <geom/geom_int.h>
60 #include <machine/stdarg.h>
61 
62 #ifdef DDB
63 #include <ddb/ddb.h>
64 #endif
65 
66 #ifdef KDB
67 #include <sys/kdb.h>
68 #endif
69 
70 SDT_PROVIDER_DEFINE(geom);
71 
72 struct class_list_head g_classes = LIST_HEAD_INITIALIZER(g_classes);
73 static struct g_tailq_head geoms = TAILQ_HEAD_INITIALIZER(geoms);
74 char *g_wait_event, *g_wait_up, *g_wait_down, *g_wait_sim;
75 
76 struct g_hh00 {
77 	struct g_class		*mp;
78 	struct g_provider	*pp;
79 	off_t			size;
80 	int			error;
81 	int			post;
82 };
83 
84 void
85 g_dbg_printf(const char *classname, int lvl, struct bio *bp,
86     const char *format,
87     ...)
88 {
89 #ifndef PRINTF_BUFR_SIZE
90 #define PRINTF_BUFR_SIZE 64
91 #endif
92 	char bufr[PRINTF_BUFR_SIZE];
93 	struct sbuf sb, *sbp __unused;
94 	va_list ap;
95 
96 	sbp = sbuf_new(&sb, bufr, sizeof(bufr), SBUF_FIXEDLEN);
97 	KASSERT(sbp != NULL, ("sbuf_new misused?"));
98 
99 	sbuf_set_drain(&sb, sbuf_printf_drain, NULL);
100 
101 	sbuf_cat(&sb, classname);
102 	if (lvl >= 0)
103 		sbuf_printf(&sb, "[%d]", lvl);
104 
105 	va_start(ap, format);
106 	sbuf_vprintf(&sb, format, ap);
107 	va_end(ap);
108 
109 	if (bp != NULL) {
110 		sbuf_putc(&sb, ' ');
111 		g_format_bio(&sb, bp);
112 	}
113 
114 	/* Terminate the debug line with a single '\n'. */
115 	sbuf_nl_terminate(&sb);
116 
117 	/* Flush line to printf. */
118 	sbuf_finish(&sb);
119 	sbuf_delete(&sb);
120 }
121 
122 /*
123  * This event offers a new class a chance to taste all preexisting providers.
124  */
125 static void
126 g_load_class(void *arg, int flag)
127 {
128 	struct g_hh00 *hh;
129 	struct g_class *mp2, *mp;
130 	struct g_geom *gp;
131 	struct g_provider *pp;
132 
133 	g_topology_assert();
134 	if (flag == EV_CANCEL)	/* XXX: can't happen ? */
135 		return;
136 	if (g_shutdown)
137 		return;
138 
139 	hh = arg;
140 	mp = hh->mp;
141 	hh->error = 0;
142 	if (hh->post) {
143 		g_free(hh);
144 		hh = NULL;
145 	}
146 	g_trace(G_T_TOPOLOGY, "g_load_class(%s)", mp->name);
147 	KASSERT(mp->name != NULL && *mp->name != '\0',
148 	    ("GEOM class has no name"));
149 	LIST_FOREACH(mp2, &g_classes, class) {
150 		if (mp2 == mp) {
151 			printf("The GEOM class %s is already loaded.\n",
152 			    mp2->name);
153 			if (hh != NULL)
154 				hh->error = EEXIST;
155 			return;
156 		} else if (strcmp(mp2->name, mp->name) == 0) {
157 			printf("A GEOM class %s is already loaded.\n",
158 			    mp2->name);
159 			if (hh != NULL)
160 				hh->error = EEXIST;
161 			return;
162 		}
163 	}
164 
165 	LIST_INIT(&mp->geom);
166 	LIST_INSERT_HEAD(&g_classes, mp, class);
167 	if (mp->init != NULL)
168 		mp->init(mp);
169 	if (mp->taste == NULL)
170 		return;
171 	LIST_FOREACH(mp2, &g_classes, class) {
172 		if (mp == mp2)
173 			continue;
174 		LIST_FOREACH(gp, &mp2->geom, geom) {
175 			LIST_FOREACH(pp, &gp->provider, provider) {
176 				mp->taste(mp, pp, 0);
177 				g_topology_assert();
178 			}
179 		}
180 	}
181 }
182 
183 static int
184 g_unload_class(struct g_class *mp)
185 {
186 	struct g_geom *gp;
187 	struct g_provider *pp;
188 	struct g_consumer *cp;
189 	int error;
190 
191 	g_topology_lock();
192 	g_trace(G_T_TOPOLOGY, "g_unload_class(%s)", mp->name);
193 retry:
194 	G_VALID_CLASS(mp);
195 	LIST_FOREACH(gp, &mp->geom, geom) {
196 		/* We refuse to unload if anything is open */
197 		LIST_FOREACH(pp, &gp->provider, provider)
198 			if (pp->acr || pp->acw || pp->ace) {
199 				g_topology_unlock();
200 				return (EBUSY);
201 			}
202 		LIST_FOREACH(cp, &gp->consumer, consumer)
203 			if (cp->acr || cp->acw || cp->ace) {
204 				g_topology_unlock();
205 				return (EBUSY);
206 			}
207 		/* If the geom is withering, wait for it to finish. */
208 		if (gp->flags & G_GEOM_WITHER) {
209 			g_topology_sleep(mp, 1);
210 			goto retry;
211 		}
212 	}
213 
214 	/*
215 	 * We allow unloading if we have no geoms, or a class
216 	 * method we can use to get rid of them.
217 	 */
218 	if (!LIST_EMPTY(&mp->geom) && mp->destroy_geom == NULL) {
219 		g_topology_unlock();
220 		return (EOPNOTSUPP);
221 	}
222 
223 	/* Bar new entries */
224 	mp->taste = NULL;
225 	mp->config = NULL;
226 
227 	LIST_FOREACH(gp, &mp->geom, geom) {
228 		error = mp->destroy_geom(NULL, mp, gp);
229 		if (error != 0) {
230 			g_topology_unlock();
231 			return (error);
232 		}
233 	}
234 	/* Wait for withering to finish. */
235 	for (;;) {
236 		gp = LIST_FIRST(&mp->geom);
237 		if (gp == NULL)
238 			break;
239 		KASSERT(gp->flags & G_GEOM_WITHER,
240 		   ("Non-withering geom in class %s", mp->name));
241 		g_topology_sleep(mp, 1);
242 	}
243 	G_VALID_CLASS(mp);
244 	if (mp->fini != NULL)
245 		mp->fini(mp);
246 	LIST_REMOVE(mp, class);
247 	g_topology_unlock();
248 
249 	return (0);
250 }
251 
252 int
253 g_modevent(module_t mod, int type, void *data)
254 {
255 	struct g_hh00 *hh;
256 	int error;
257 	static int g_ignition;
258 	struct g_class *mp;
259 
260 	mp = data;
261 	if (mp->version != G_VERSION) {
262 		printf("GEOM class %s has Wrong version %x\n",
263 		    mp->name, mp->version);
264 		return (EINVAL);
265 	}
266 	if (!g_ignition) {
267 		g_ignition++;
268 		g_init();
269 	}
270 	error = EOPNOTSUPP;
271 	switch (type) {
272 	case MOD_LOAD:
273 		g_trace(G_T_TOPOLOGY, "g_modevent(%s, LOAD)", mp->name);
274 		hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
275 		hh->mp = mp;
276 		/*
277 		 * Once the system is not cold, MOD_LOAD calls will be
278 		 * from the userland and the g_event thread will be able
279 		 * to acknowledge their completion.
280 		 */
281 		if (cold) {
282 			hh->post = 1;
283 			error = g_post_event(g_load_class, hh, M_WAITOK, NULL);
284 		} else {
285 			error = g_waitfor_event(g_load_class, hh, M_WAITOK,
286 			    NULL);
287 			if (error == 0)
288 				error = hh->error;
289 			g_free(hh);
290 		}
291 		break;
292 	case MOD_UNLOAD:
293 		g_trace(G_T_TOPOLOGY, "g_modevent(%s, UNLOAD)", mp->name);
294 		error = g_unload_class(mp);
295 		if (error == 0) {
296 			KASSERT(LIST_EMPTY(&mp->geom),
297 			    ("Unloaded class (%s) still has geom", mp->name));
298 		}
299 		break;
300 	}
301 	return (error);
302 }
303 
304 static void
305 g_retaste_event(void *arg, int flag)
306 {
307 	struct g_class *mp, *mp2;
308 	struct g_geom *gp;
309 	struct g_hh00 *hh;
310 	struct g_provider *pp;
311 	struct g_consumer *cp;
312 
313 	g_topology_assert();
314 	if (flag == EV_CANCEL)  /* XXX: can't happen ? */
315 		return;
316 	if (g_shutdown || g_notaste)
317 		return;
318 
319 	hh = arg;
320 	mp = hh->mp;
321 	hh->error = 0;
322 	if (hh->post) {
323 		g_free(hh);
324 		hh = NULL;
325 	}
326 	g_trace(G_T_TOPOLOGY, "g_retaste(%s)", mp->name);
327 
328 	LIST_FOREACH(mp2, &g_classes, class) {
329 		LIST_FOREACH(gp, &mp2->geom, geom) {
330 			LIST_FOREACH(pp, &gp->provider, provider) {
331 				if (pp->acr || pp->acw || pp->ace)
332 					continue;
333 				LIST_FOREACH(cp, &pp->consumers, consumers) {
334 					if (cp->geom->class == mp &&
335 					    (cp->flags & G_CF_ORPHAN) == 0)
336 						break;
337 				}
338 				if (cp != NULL) {
339 					cp->flags |= G_CF_ORPHAN;
340 					g_wither_geom(cp->geom, ENXIO);
341 				}
342 				mp->taste(mp, pp, 0);
343 				g_topology_assert();
344 			}
345 		}
346 	}
347 }
348 
349 int
350 g_retaste(struct g_class *mp)
351 {
352 	struct g_hh00 *hh;
353 	int error;
354 
355 	if (mp->taste == NULL)
356 		return (EINVAL);
357 
358 	hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
359 	hh->mp = mp;
360 
361 	if (cold) {
362 		hh->post = 1;
363 		error = g_post_event(g_retaste_event, hh, M_WAITOK, NULL);
364 	} else {
365 		error = g_waitfor_event(g_retaste_event, hh, M_WAITOK, NULL);
366 		if (error == 0)
367 			error = hh->error;
368 		g_free(hh);
369 	}
370 
371 	return (error);
372 }
373 
374 struct g_geom *
375 g_new_geomf(struct g_class *mp, const char *fmt, ...)
376 {
377 	struct g_geom *gp;
378 	va_list ap;
379 	struct sbuf *sb;
380 
381 	g_topology_assert();
382 	G_VALID_CLASS(mp);
383 	sb = sbuf_new_auto();
384 	va_start(ap, fmt);
385 	sbuf_vprintf(sb, fmt, ap);
386 	va_end(ap);
387 	sbuf_finish(sb);
388 	gp = g_malloc(sizeof *gp, M_WAITOK | M_ZERO);
389 	gp->name = g_malloc(sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
390 	gp->class = mp;
391 	gp->rank = 1;
392 	LIST_INIT(&gp->consumer);
393 	LIST_INIT(&gp->provider);
394 	LIST_INSERT_HEAD(&mp->geom, gp, geom);
395 	TAILQ_INSERT_HEAD(&geoms, gp, geoms);
396 	strcpy(gp->name, sbuf_data(sb));
397 	sbuf_delete(sb);
398 	/* Fill in defaults from class */
399 	gp->start = mp->start;
400 	gp->spoiled = mp->spoiled;
401 	gp->attrchanged = mp->attrchanged;
402 	gp->providergone = mp->providergone;
403 	gp->dumpconf = mp->dumpconf;
404 	gp->access = mp->access;
405 	gp->orphan = mp->orphan;
406 	gp->ioctl = mp->ioctl;
407 	gp->resize = mp->resize;
408 	return (gp);
409 }
410 
411 void
412 g_destroy_geom(struct g_geom *gp)
413 {
414 
415 	g_topology_assert();
416 	G_VALID_GEOM(gp);
417 	g_trace(G_T_TOPOLOGY, "g_destroy_geom(%p(%s))", gp, gp->name);
418 	KASSERT(LIST_EMPTY(&gp->consumer),
419 	    ("g_destroy_geom(%s) with consumer(s) [%p]",
420 	    gp->name, LIST_FIRST(&gp->consumer)));
421 	KASSERT(LIST_EMPTY(&gp->provider),
422 	    ("g_destroy_geom(%s) with provider(s) [%p]",
423 	    gp->name, LIST_FIRST(&gp->provider)));
424 	g_cancel_event(gp);
425 	LIST_REMOVE(gp, geom);
426 	TAILQ_REMOVE(&geoms, gp, geoms);
427 	g_free(gp->name);
428 	g_free(gp);
429 }
430 
431 /*
432  * This function is called (repeatedly) until the geom has withered away.
433  */
434 void
435 g_wither_geom(struct g_geom *gp, int error)
436 {
437 	struct g_provider *pp;
438 
439 	g_topology_assert();
440 	G_VALID_GEOM(gp);
441 	g_trace(G_T_TOPOLOGY, "g_wither_geom(%p(%s))", gp, gp->name);
442 	if (!(gp->flags & G_GEOM_WITHER)) {
443 		gp->flags |= G_GEOM_WITHER;
444 		LIST_FOREACH(pp, &gp->provider, provider)
445 			if (!(pp->flags & G_PF_ORPHAN))
446 				g_orphan_provider(pp, error);
447 	}
448 	g_do_wither();
449 }
450 
451 /*
452  * Convenience function to destroy a particular provider.
453  */
454 void
455 g_wither_provider(struct g_provider *pp, int error)
456 {
457 
458 	pp->flags |= G_PF_WITHER;
459 	if (!(pp->flags & G_PF_ORPHAN))
460 		g_orphan_provider(pp, error);
461 }
462 
463 /*
464  * This function is called (repeatedly) until the has withered away.
465  */
466 void
467 g_wither_geom_close(struct g_geom *gp, int error)
468 {
469 	struct g_consumer *cp;
470 
471 	g_topology_assert();
472 	G_VALID_GEOM(gp);
473 	g_trace(G_T_TOPOLOGY, "g_wither_geom_close(%p(%s))", gp, gp->name);
474 	LIST_FOREACH(cp, &gp->consumer, consumer)
475 		if (cp->acr || cp->acw || cp->ace)
476 			g_access(cp, -cp->acr, -cp->acw, -cp->ace);
477 	g_wither_geom(gp, error);
478 }
479 
480 /*
481  * This function is called (repeatedly) until we cant wash away more
482  * withered bits at present.
483  */
484 void
485 g_wither_washer()
486 {
487 	struct g_class *mp;
488 	struct g_geom *gp, *gp2;
489 	struct g_provider *pp, *pp2;
490 	struct g_consumer *cp, *cp2;
491 
492 	g_topology_assert();
493 	LIST_FOREACH(mp, &g_classes, class) {
494 		LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
495 			LIST_FOREACH_SAFE(pp, &gp->provider, provider, pp2) {
496 				if (!(pp->flags & G_PF_WITHER))
497 					continue;
498 				if (LIST_EMPTY(&pp->consumers))
499 					g_destroy_provider(pp);
500 			}
501 			if (!(gp->flags & G_GEOM_WITHER))
502 				continue;
503 			LIST_FOREACH_SAFE(pp, &gp->provider, provider, pp2) {
504 				if (LIST_EMPTY(&pp->consumers))
505 					g_destroy_provider(pp);
506 			}
507 			LIST_FOREACH_SAFE(cp, &gp->consumer, consumer, cp2) {
508 				if (cp->acr || cp->acw || cp->ace)
509 					continue;
510 				if (cp->provider != NULL)
511 					g_detach(cp);
512 				g_destroy_consumer(cp);
513 			}
514 			if (LIST_EMPTY(&gp->provider) &&
515 			    LIST_EMPTY(&gp->consumer))
516 				g_destroy_geom(gp);
517 		}
518 	}
519 }
520 
521 struct g_consumer *
522 g_new_consumer(struct g_geom *gp)
523 {
524 	struct g_consumer *cp;
525 
526 	g_topology_assert();
527 	G_VALID_GEOM(gp);
528 	KASSERT(!(gp->flags & G_GEOM_WITHER),
529 	    ("g_new_consumer on WITHERing geom(%s) (class %s)",
530 	    gp->name, gp->class->name));
531 	KASSERT(gp->orphan != NULL,
532 	    ("g_new_consumer on geom(%s) (class %s) without orphan",
533 	    gp->name, gp->class->name));
534 
535 	cp = g_malloc(sizeof *cp, M_WAITOK | M_ZERO);
536 	cp->geom = gp;
537 	cp->stat = devstat_new_entry(cp, -1, 0, DEVSTAT_ALL_SUPPORTED,
538 	    DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
539 	LIST_INSERT_HEAD(&gp->consumer, cp, consumer);
540 	return(cp);
541 }
542 
543 void
544 g_destroy_consumer(struct g_consumer *cp)
545 {
546 	struct g_geom *gp;
547 
548 	g_topology_assert();
549 	G_VALID_CONSUMER(cp);
550 	g_trace(G_T_TOPOLOGY, "g_destroy_consumer(%p)", cp);
551 	KASSERT (cp->provider == NULL, ("g_destroy_consumer but attached"));
552 	KASSERT (cp->acr == 0, ("g_destroy_consumer with acr"));
553 	KASSERT (cp->acw == 0, ("g_destroy_consumer with acw"));
554 	KASSERT (cp->ace == 0, ("g_destroy_consumer with ace"));
555 	g_cancel_event(cp);
556 	gp = cp->geom;
557 	LIST_REMOVE(cp, consumer);
558 	devstat_remove_entry(cp->stat);
559 	g_free(cp);
560 	if (gp->flags & G_GEOM_WITHER)
561 		g_do_wither();
562 }
563 
564 static void
565 g_new_provider_event(void *arg, int flag)
566 {
567 	struct g_class *mp;
568 	struct g_provider *pp;
569 	struct g_consumer *cp, *next_cp;
570 
571 	g_topology_assert();
572 	if (flag == EV_CANCEL)
573 		return;
574 	if (g_shutdown)
575 		return;
576 	pp = arg;
577 	G_VALID_PROVIDER(pp);
578 	KASSERT(!(pp->flags & G_PF_WITHER),
579 	    ("g_new_provider_event but withered"));
580 	LIST_FOREACH_SAFE(cp, &pp->consumers, consumers, next_cp) {
581 		if ((cp->flags & G_CF_ORPHAN) == 0 &&
582 		    cp->geom->attrchanged != NULL)
583 			cp->geom->attrchanged(cp, "GEOM::media");
584 	}
585 	if (g_notaste)
586 		return;
587 	LIST_FOREACH(mp, &g_classes, class) {
588 		if (mp->taste == NULL)
589 			continue;
590 		LIST_FOREACH(cp, &pp->consumers, consumers)
591 			if (cp->geom->class == mp &&
592 			    (cp->flags & G_CF_ORPHAN) == 0)
593 				break;
594 		if (cp != NULL)
595 			continue;
596 		mp->taste(mp, pp, 0);
597 		g_topology_assert();
598 	}
599 }
600 
601 struct g_provider *
602 g_new_providerf(struct g_geom *gp, const char *fmt, ...)
603 {
604 	struct g_provider *pp;
605 	struct sbuf *sb;
606 	va_list ap;
607 
608 	g_topology_assert();
609 	G_VALID_GEOM(gp);
610 	KASSERT(gp->access != NULL,
611 	    ("new provider on geom(%s) without ->access (class %s)",
612 	    gp->name, gp->class->name));
613 	KASSERT(gp->start != NULL,
614 	    ("new provider on geom(%s) without ->start (class %s)",
615 	    gp->name, gp->class->name));
616 	KASSERT(!(gp->flags & G_GEOM_WITHER),
617 	    ("new provider on WITHERing geom(%s) (class %s)",
618 	    gp->name, gp->class->name));
619 	sb = sbuf_new_auto();
620 	va_start(ap, fmt);
621 	sbuf_vprintf(sb, fmt, ap);
622 	va_end(ap);
623 	sbuf_finish(sb);
624 	pp = g_malloc(sizeof *pp + sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
625 	pp->name = (char *)(pp + 1);
626 	strcpy(pp->name, sbuf_data(sb));
627 	sbuf_delete(sb);
628 	LIST_INIT(&pp->consumers);
629 	LIST_INIT(&pp->aliases);
630 	pp->error = ENXIO;
631 	pp->geom = gp;
632 	pp->stat = devstat_new_entry(pp, -1, 0, DEVSTAT_ALL_SUPPORTED,
633 	    DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
634 	LIST_INSERT_HEAD(&gp->provider, pp, provider);
635 	g_post_event(g_new_provider_event, pp, M_WAITOK, pp, gp, NULL);
636 	return (pp);
637 }
638 
639 void
640 g_provider_add_alias(struct g_provider *pp, const char *fmt, ...)
641 {
642 	struct sbuf *sb;
643 	struct g_geom_alias *gap;
644 	va_list ap;
645 
646 	/*
647 	 * Generate the alias string and save it in the list.
648 	 */
649 	sb = sbuf_new_auto();
650 	va_start(ap, fmt);
651 	sbuf_vprintf(sb, fmt, ap);
652 	va_end(ap);
653 	sbuf_finish(sb);
654 
655 	LIST_FOREACH(gap, &pp->aliases, ga_next) {
656 		if (strcmp(gap->ga_alias, sbuf_data(sb)) != 0)
657 			continue;
658 		/* Don't re-add the same alias. */
659 		sbuf_delete(sb);
660 		return;
661 	}
662 
663 	gap = g_malloc(sizeof(*gap) + sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
664 	memcpy((char *)(gap + 1), sbuf_data(sb), sbuf_len(sb));
665 	sbuf_delete(sb);
666 	gap->ga_alias = (const char *)(gap + 1);
667 	LIST_INSERT_HEAD(&pp->aliases, gap, ga_next);
668 }
669 
670 void
671 g_error_provider(struct g_provider *pp, int error)
672 {
673 
674 	/* G_VALID_PROVIDER(pp);  We may not have g_topology */
675 	pp->error = error;
676 }
677 
678 static void
679 g_resize_provider_event(void *arg, int flag)
680 {
681 	struct g_hh00 *hh;
682 	struct g_class *mp;
683 	struct g_geom *gp;
684 	struct g_provider *pp;
685 	struct g_consumer *cp, *cp2;
686 	off_t size;
687 
688 	g_topology_assert();
689 	if (g_shutdown)
690 		return;
691 
692 	hh = arg;
693 	pp = hh->pp;
694 	size = hh->size;
695 	g_free(hh);
696 
697 	G_VALID_PROVIDER(pp);
698 	KASSERT(!(pp->flags & G_PF_WITHER),
699 	    ("g_resize_provider_event but withered"));
700 	g_trace(G_T_TOPOLOGY, "g_resize_provider_event(%p)", pp);
701 
702 	LIST_FOREACH_SAFE(cp, &pp->consumers, consumers, cp2) {
703 		gp = cp->geom;
704 		if (gp->resize == NULL && size < pp->mediasize) {
705 			/*
706 			 * XXX: g_dev_orphan method does deferred destroying
707 			 * and it is possible, that other event could already
708 			 * call the orphan method. Check consumer's flags to
709 			 * do not schedule it twice.
710 			 */
711 			if (cp->flags & G_CF_ORPHAN)
712 				continue;
713 			cp->flags |= G_CF_ORPHAN;
714 			cp->geom->orphan(cp);
715 		}
716 	}
717 
718 	pp->mediasize = size;
719 
720 	LIST_FOREACH_SAFE(cp, &pp->consumers, consumers, cp2) {
721 		gp = cp->geom;
722 		if ((gp->flags & G_GEOM_WITHER) == 0 && gp->resize != NULL)
723 			gp->resize(cp);
724 	}
725 
726 	/*
727 	 * After resizing, the previously invalid GEOM class metadata
728 	 * might become valid.  This means we should retaste.
729 	 */
730 	LIST_FOREACH(mp, &g_classes, class) {
731 		if (mp->taste == NULL)
732 			continue;
733 		LIST_FOREACH(cp, &pp->consumers, consumers)
734 			if (cp->geom->class == mp &&
735 			    (cp->flags & G_CF_ORPHAN) == 0)
736 				break;
737 		if (cp != NULL)
738 			continue;
739 		mp->taste(mp, pp, 0);
740 		g_topology_assert();
741 	}
742 }
743 
744 void
745 g_resize_provider(struct g_provider *pp, off_t size)
746 {
747 	struct g_hh00 *hh;
748 
749 	G_VALID_PROVIDER(pp);
750 	if (pp->flags & G_PF_WITHER)
751 		return;
752 
753 	if (size == pp->mediasize)
754 		return;
755 
756 	hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
757 	hh->pp = pp;
758 	hh->size = size;
759 	g_post_event(g_resize_provider_event, hh, M_WAITOK, NULL);
760 }
761 
762 struct g_provider *
763 g_provider_by_name(char const *arg)
764 {
765 	struct g_class *cp;
766 	struct g_geom *gp;
767 	struct g_provider *pp, *wpp;
768 
769 	if (strncmp(arg, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
770 		arg += sizeof(_PATH_DEV) - 1;
771 
772 	wpp = NULL;
773 	LIST_FOREACH(cp, &g_classes, class) {
774 		LIST_FOREACH(gp, &cp->geom, geom) {
775 			LIST_FOREACH(pp, &gp->provider, provider) {
776 				if (strcmp(arg, pp->name) != 0)
777 					continue;
778 				if ((gp->flags & G_GEOM_WITHER) == 0 &&
779 				    (pp->flags & G_PF_WITHER) == 0)
780 					return (pp);
781 				else
782 					wpp = pp;
783 			}
784 		}
785 	}
786 
787 	return (wpp);
788 }
789 
790 void
791 g_destroy_provider(struct g_provider *pp)
792 {
793 	struct g_geom *gp;
794 	struct g_geom_alias *gap, *gaptmp;
795 
796 	g_topology_assert();
797 	G_VALID_PROVIDER(pp);
798 	KASSERT(LIST_EMPTY(&pp->consumers),
799 	    ("g_destroy_provider but attached"));
800 	KASSERT (pp->acr == 0, ("g_destroy_provider with acr"));
801 	KASSERT (pp->acw == 0, ("g_destroy_provider with acw"));
802 	KASSERT (pp->ace == 0, ("g_destroy_provider with ace"));
803 	g_cancel_event(pp);
804 	LIST_REMOVE(pp, provider);
805 	gp = pp->geom;
806 	devstat_remove_entry(pp->stat);
807 	/*
808 	 * If a callback was provided, send notification that the provider
809 	 * is now gone.
810 	 */
811 	if (gp->providergone != NULL)
812 		gp->providergone(pp);
813 	LIST_FOREACH_SAFE(gap, &pp->aliases, ga_next, gaptmp)
814 		g_free(gap);
815 	g_free(pp);
816 	if ((gp->flags & G_GEOM_WITHER))
817 		g_do_wither();
818 }
819 
820 /*
821  * We keep the "geoms" list sorted by topological order (== increasing
822  * numerical rank) at all times.
823  * When an attach is done, the attaching geoms rank is invalidated
824  * and it is moved to the tail of the list.
825  * All geoms later in the sequence has their ranks reevaluated in
826  * sequence.  If we cannot assign rank to a geom because it's
827  * prerequisites do not have rank, we move that element to the tail
828  * of the sequence with invalid rank as well.
829  * At some point we encounter our original geom and if we stil fail
830  * to assign it a rank, there must be a loop and we fail back to
831  * g_attach() which detach again and calls redo_rank again
832  * to fix up the damage.
833  * It would be much simpler code wise to do it recursively, but we
834  * can't risk that on the kernel stack.
835  */
836 
837 static int
838 redo_rank(struct g_geom *gp)
839 {
840 	struct g_consumer *cp;
841 	struct g_geom *gp1, *gp2;
842 	int n, m;
843 
844 	g_topology_assert();
845 	G_VALID_GEOM(gp);
846 
847 	/* Invalidate this geoms rank and move it to the tail */
848 	gp1 = TAILQ_NEXT(gp, geoms);
849 	if (gp1 != NULL) {
850 		gp->rank = 0;
851 		TAILQ_REMOVE(&geoms, gp, geoms);
852 		TAILQ_INSERT_TAIL(&geoms, gp, geoms);
853 	} else {
854 		gp1 = gp;
855 	}
856 
857 	/* re-rank the rest of the sequence */
858 	for (; gp1 != NULL; gp1 = gp2) {
859 		gp1->rank = 0;
860 		m = 1;
861 		LIST_FOREACH(cp, &gp1->consumer, consumer) {
862 			if (cp->provider == NULL)
863 				continue;
864 			n = cp->provider->geom->rank;
865 			if (n == 0) {
866 				m = 0;
867 				break;
868 			} else if (n >= m)
869 				m = n + 1;
870 		}
871 		gp1->rank = m;
872 		gp2 = TAILQ_NEXT(gp1, geoms);
873 
874 		/* got a rank, moving on */
875 		if (m != 0)
876 			continue;
877 
878 		/* no rank to original geom means loop */
879 		if (gp == gp1)
880 			return (ELOOP);
881 
882 		/* no rank, put it at the end move on */
883 		TAILQ_REMOVE(&geoms, gp1, geoms);
884 		TAILQ_INSERT_TAIL(&geoms, gp1, geoms);
885 	}
886 	return (0);
887 }
888 
889 int
890 g_attach(struct g_consumer *cp, struct g_provider *pp)
891 {
892 	int error;
893 
894 	g_topology_assert();
895 	G_VALID_CONSUMER(cp);
896 	G_VALID_PROVIDER(pp);
897 	g_trace(G_T_TOPOLOGY, "g_attach(%p, %p)", cp, pp);
898 	KASSERT(cp->provider == NULL, ("attach but attached"));
899 	cp->provider = pp;
900 	cp->flags &= ~G_CF_ORPHAN;
901 	LIST_INSERT_HEAD(&pp->consumers, cp, consumers);
902 	error = redo_rank(cp->geom);
903 	if (error) {
904 		LIST_REMOVE(cp, consumers);
905 		cp->provider = NULL;
906 		redo_rank(cp->geom);
907 	}
908 	return (error);
909 }
910 
911 void
912 g_detach(struct g_consumer *cp)
913 {
914 	struct g_provider *pp;
915 
916 	g_topology_assert();
917 	G_VALID_CONSUMER(cp);
918 	g_trace(G_T_TOPOLOGY, "g_detach(%p)", cp);
919 	KASSERT(cp->provider != NULL, ("detach but not attached"));
920 	KASSERT(cp->acr == 0, ("detach but nonzero acr"));
921 	KASSERT(cp->acw == 0, ("detach but nonzero acw"));
922 	KASSERT(cp->ace == 0, ("detach but nonzero ace"));
923 	KASSERT(cp->nstart == cp->nend,
924 	    ("detach with active requests"));
925 	pp = cp->provider;
926 	LIST_REMOVE(cp, consumers);
927 	cp->provider = NULL;
928 	if ((cp->geom->flags & G_GEOM_WITHER) ||
929 	    (pp->geom->flags & G_GEOM_WITHER) ||
930 	    (pp->flags & G_PF_WITHER))
931 		g_do_wither();
932 	redo_rank(cp->geom);
933 }
934 
935 /*
936  * g_access()
937  *
938  * Access-check with delta values.  The question asked is "can provider
939  * "cp" change the access counters by the relative amounts dc[rwe] ?"
940  */
941 
942 int
943 g_access(struct g_consumer *cp, int dcr, int dcw, int dce)
944 {
945 	struct g_provider *pp;
946 	struct g_geom *gp;
947 	int pw, pe;
948 #ifdef INVARIANTS
949 	int sr, sw, se;
950 #endif
951 	int error;
952 
953 	g_topology_assert();
954 	G_VALID_CONSUMER(cp);
955 	pp = cp->provider;
956 	KASSERT(pp != NULL, ("access but not attached"));
957 	G_VALID_PROVIDER(pp);
958 	gp = pp->geom;
959 
960 	g_trace(G_T_ACCESS, "g_access(%p(%s), %d, %d, %d)",
961 	    cp, pp->name, dcr, dcw, dce);
962 
963 	KASSERT(cp->acr + dcr >= 0, ("access resulting in negative acr"));
964 	KASSERT(cp->acw + dcw >= 0, ("access resulting in negative acw"));
965 	KASSERT(cp->ace + dce >= 0, ("access resulting in negative ace"));
966 	KASSERT(dcr != 0 || dcw != 0 || dce != 0, ("NOP access request"));
967 	KASSERT(cp->acr + dcr != 0 || cp->acw + dcw != 0 ||
968 	    cp->ace + dce != 0 || cp->nstart == cp->nend,
969 	    ("Last close with active requests"));
970 	KASSERT(gp->access != NULL, ("NULL geom->access"));
971 
972 	/*
973 	 * If our class cares about being spoiled, and we have been, we
974 	 * are probably just ahead of the event telling us that.  Fail
975 	 * now rather than having to unravel this later.
976 	 */
977 	if (cp->geom->spoiled != NULL && (cp->flags & G_CF_SPOILED) &&
978 	    (dcr > 0 || dcw > 0 || dce > 0))
979 		return (ENXIO);
980 
981 	/*
982 	 * A number of GEOM classes either need to perform an I/O on the first
983 	 * open or to acquire a different subsystem's lock.  To do that they
984 	 * may have to drop the topology lock.
985 	 * Other GEOM classes perform special actions when opening a lower rank
986 	 * geom for the first time.  As a result, more than one thread may
987 	 * end up performing the special actions.
988 	 * So, we prevent concurrent "first" opens by marking the consumer with
989 	 * special flag.
990 	 *
991 	 * Note that if the geom's access method never drops the topology lock,
992 	 * then we will never see G_GEOM_IN_ACCESS here.
993 	 */
994 	while ((gp->flags & G_GEOM_IN_ACCESS) != 0) {
995 		g_trace(G_T_ACCESS,
996 		    "%s: race on geom %s via provider %s and consumer of %s",
997 		    __func__, gp->name, pp->name, cp->geom->name);
998 		gp->flags |= G_GEOM_ACCESS_WAIT;
999 		g_topology_sleep(gp, 0);
1000 	}
1001 
1002 	/*
1003 	 * Figure out what counts the provider would have had, if this
1004 	 * consumer had (r0w0e0) at this time.
1005 	 */
1006 	pw = pp->acw - cp->acw;
1007 	pe = pp->ace - cp->ace;
1008 
1009 	g_trace(G_T_ACCESS,
1010     "open delta:[r%dw%de%d] old:[r%dw%de%d] provider:[r%dw%de%d] %p(%s)",
1011 	    dcr, dcw, dce,
1012 	    cp->acr, cp->acw, cp->ace,
1013 	    pp->acr, pp->acw, pp->ace,
1014 	    pp, pp->name);
1015 
1016 	/* If foot-shooting is enabled, any open on rank#1 is OK */
1017 	if ((g_debugflags & G_F_FOOTSHOOTING) && gp->rank == 1)
1018 		;
1019 	/* If we try exclusive but already write: fail */
1020 	else if (dce > 0 && pw > 0)
1021 		return (EPERM);
1022 	/* If we try write but already exclusive: fail */
1023 	else if (dcw > 0 && pe > 0)
1024 		return (EPERM);
1025 	/* If we try to open more but provider is error'ed: fail */
1026 	else if ((dcr > 0 || dcw > 0 || dce > 0) && pp->error != 0) {
1027 		printf("%s(%d): provider %s has error %d set\n",
1028 		    __func__, __LINE__, pp->name, pp->error);
1029 		return (pp->error);
1030 	}
1031 
1032 	/* Ok then... */
1033 
1034 #ifdef INVARIANTS
1035 	sr = cp->acr;
1036 	sw = cp->acw;
1037 	se = cp->ace;
1038 #endif
1039 	gp->flags |= G_GEOM_IN_ACCESS;
1040 	error = gp->access(pp, dcr, dcw, dce);
1041 	KASSERT(dcr > 0 || dcw > 0 || dce > 0 || error == 0,
1042 	    ("Geom provider %s::%s dcr=%d dcw=%d dce=%d error=%d failed "
1043 	    "closing ->access()", gp->class->name, pp->name, dcr, dcw,
1044 	    dce, error));
1045 
1046 	g_topology_assert();
1047 	gp->flags &= ~G_GEOM_IN_ACCESS;
1048 	KASSERT(cp->acr == sr && cp->acw == sw && cp->ace == se,
1049 	    ("Access counts changed during geom->access"));
1050 	if ((gp->flags & G_GEOM_ACCESS_WAIT) != 0) {
1051 		gp->flags &= ~G_GEOM_ACCESS_WAIT;
1052 		wakeup(gp);
1053 	}
1054 
1055 	if (!error) {
1056 		/*
1057 		 * If we open first write, spoil any partner consumers.
1058 		 * If we close last write and provider is not errored,
1059 		 * trigger re-taste.
1060 		 */
1061 		if (pp->acw == 0 && dcw != 0)
1062 			g_spoil(pp, cp);
1063 		else if (pp->acw != 0 && pp->acw == -dcw && pp->error == 0 &&
1064 		    !(gp->flags & G_GEOM_WITHER))
1065 			g_post_event(g_new_provider_event, pp, M_WAITOK,
1066 			    pp, NULL);
1067 
1068 		pp->acr += dcr;
1069 		pp->acw += dcw;
1070 		pp->ace += dce;
1071 		cp->acr += dcr;
1072 		cp->acw += dcw;
1073 		cp->ace += dce;
1074 		if (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)
1075 			KASSERT(pp->sectorsize > 0,
1076 			    ("Provider %s lacks sectorsize", pp->name));
1077 		if ((cp->geom->flags & G_GEOM_WITHER) &&
1078 		    cp->acr == 0 && cp->acw == 0 && cp->ace == 0)
1079 			g_do_wither();
1080 	}
1081 	return (error);
1082 }
1083 
1084 int
1085 g_handleattr_int(struct bio *bp, const char *attribute, int val)
1086 {
1087 
1088 	return (g_handleattr(bp, attribute, &val, sizeof val));
1089 }
1090 
1091 int
1092 g_handleattr_uint16_t(struct bio *bp, const char *attribute, uint16_t val)
1093 {
1094 
1095 	return (g_handleattr(bp, attribute, &val, sizeof val));
1096 }
1097 
1098 int
1099 g_handleattr_off_t(struct bio *bp, const char *attribute, off_t val)
1100 {
1101 
1102 	return (g_handleattr(bp, attribute, &val, sizeof val));
1103 }
1104 
1105 int
1106 g_handleattr_str(struct bio *bp, const char *attribute, const char *str)
1107 {
1108 
1109 	return (g_handleattr(bp, attribute, str, 0));
1110 }
1111 
1112 int
1113 g_handleattr(struct bio *bp, const char *attribute, const void *val, int len)
1114 {
1115 	int error = 0;
1116 
1117 	if (strcmp(bp->bio_attribute, attribute))
1118 		return (0);
1119 	if (len == 0) {
1120 		bzero(bp->bio_data, bp->bio_length);
1121 		if (strlcpy(bp->bio_data, val, bp->bio_length) >=
1122 		    bp->bio_length) {
1123 			printf("%s: %s %s bio_length %jd strlen %zu -> EFAULT\n",
1124 			    __func__, bp->bio_to->name, attribute,
1125 			    (intmax_t)bp->bio_length, strlen(val));
1126 			error = EFAULT;
1127 		}
1128 	} else if (bp->bio_length == len) {
1129 		bcopy(val, bp->bio_data, len);
1130 	} else {
1131 		printf("%s: %s %s bio_length %jd len %d -> EFAULT\n", __func__,
1132 		    bp->bio_to->name, attribute, (intmax_t)bp->bio_length, len);
1133 		error = EFAULT;
1134 	}
1135 	if (error == 0)
1136 		bp->bio_completed = bp->bio_length;
1137 	g_io_deliver(bp, error);
1138 	return (1);
1139 }
1140 
1141 int
1142 g_std_access(struct g_provider *pp,
1143 	int dr __unused, int dw __unused, int de __unused)
1144 {
1145 
1146 	g_topology_assert();
1147 	G_VALID_PROVIDER(pp);
1148         return (0);
1149 }
1150 
1151 void
1152 g_std_done(struct bio *bp)
1153 {
1154 	struct bio *bp2;
1155 
1156 	bp2 = bp->bio_parent;
1157 	if (bp2->bio_error == 0)
1158 		bp2->bio_error = bp->bio_error;
1159 	bp2->bio_completed += bp->bio_completed;
1160 	g_destroy_bio(bp);
1161 	bp2->bio_inbed++;
1162 	if (bp2->bio_children == bp2->bio_inbed) {
1163 		if (bp2->bio_cmd == BIO_SPEEDUP)
1164 			bp2->bio_completed = bp2->bio_length;
1165 		g_io_deliver(bp2, bp2->bio_error);
1166 	}
1167 }
1168 
1169 /* XXX: maybe this is only g_slice_spoiled */
1170 
1171 void
1172 g_std_spoiled(struct g_consumer *cp)
1173 {
1174 	struct g_geom *gp;
1175 	struct g_provider *pp;
1176 
1177 	g_topology_assert();
1178 	G_VALID_CONSUMER(cp);
1179 	g_trace(G_T_TOPOLOGY, "g_std_spoiled(%p)", cp);
1180 	cp->flags |= G_CF_ORPHAN;
1181 	g_detach(cp);
1182 	gp = cp->geom;
1183 	LIST_FOREACH(pp, &gp->provider, provider)
1184 		g_orphan_provider(pp, ENXIO);
1185 	g_destroy_consumer(cp);
1186 	if (LIST_EMPTY(&gp->provider) && LIST_EMPTY(&gp->consumer))
1187 		g_destroy_geom(gp);
1188 	else
1189 		gp->flags |= G_GEOM_WITHER;
1190 }
1191 
1192 /*
1193  * Spoiling happens when a provider is opened for writing, but consumers
1194  * which are configured by in-band data are attached (slicers for instance).
1195  * Since the write might potentially change the in-band data, such consumers
1196  * need to re-evaluate their existence after the writing session closes.
1197  * We do this by (offering to) tear them down when the open for write happens
1198  * in return for a re-taste when it closes again.
1199  * Together with the fact that such consumers grab an 'e' bit whenever they
1200  * are open, regardless of mode, this ends up DTRT.
1201  */
1202 
1203 static void
1204 g_spoil_event(void *arg, int flag)
1205 {
1206 	struct g_provider *pp;
1207 	struct g_consumer *cp, *cp2;
1208 
1209 	g_topology_assert();
1210 	if (flag == EV_CANCEL)
1211 		return;
1212 	pp = arg;
1213 	G_VALID_PROVIDER(pp);
1214 	g_trace(G_T_TOPOLOGY, "%s %p(%s:%s:%s)", __func__, pp,
1215 	    pp->geom->class->name, pp->geom->name, pp->name);
1216 	for (cp = LIST_FIRST(&pp->consumers); cp != NULL; cp = cp2) {
1217 		cp2 = LIST_NEXT(cp, consumers);
1218 		if ((cp->flags & G_CF_SPOILED) == 0)
1219 			continue;
1220 		cp->flags &= ~G_CF_SPOILED;
1221 		if (cp->geom->spoiled == NULL)
1222 			continue;
1223 		cp->geom->spoiled(cp);
1224 		g_topology_assert();
1225 	}
1226 }
1227 
1228 void
1229 g_spoil(struct g_provider *pp, struct g_consumer *cp)
1230 {
1231 	struct g_consumer *cp2;
1232 
1233 	g_topology_assert();
1234 	G_VALID_PROVIDER(pp);
1235 	G_VALID_CONSUMER(cp);
1236 
1237 	LIST_FOREACH(cp2, &pp->consumers, consumers) {
1238 		if (cp2 == cp)
1239 			continue;
1240 /*
1241 		KASSERT(cp2->acr == 0, ("spoiling cp->acr = %d", cp2->acr));
1242 		KASSERT(cp2->acw == 0, ("spoiling cp->acw = %d", cp2->acw));
1243 */
1244 		KASSERT(cp2->ace == 0, ("spoiling cp->ace = %d", cp2->ace));
1245 		cp2->flags |= G_CF_SPOILED;
1246 	}
1247 	g_post_event(g_spoil_event, pp, M_WAITOK, pp, NULL);
1248 }
1249 
1250 static void
1251 g_media_changed_event(void *arg, int flag)
1252 {
1253 	struct g_provider *pp;
1254 	int retaste;
1255 
1256 	g_topology_assert();
1257 	if (flag == EV_CANCEL)
1258 		return;
1259 	pp = arg;
1260 	G_VALID_PROVIDER(pp);
1261 
1262 	/*
1263 	 * If provider was not open for writing, queue retaste after spoiling.
1264 	 * If it was, retaste will happen automatically on close.
1265 	 */
1266 	retaste = (pp->acw == 0 && pp->error == 0 &&
1267 	    !(pp->geom->flags & G_GEOM_WITHER));
1268 	g_spoil_event(arg, flag);
1269 	if (retaste)
1270 		g_post_event(g_new_provider_event, pp, M_WAITOK, pp, NULL);
1271 }
1272 
1273 int
1274 g_media_changed(struct g_provider *pp, int flag)
1275 {
1276 	struct g_consumer *cp;
1277 
1278 	LIST_FOREACH(cp, &pp->consumers, consumers)
1279 		cp->flags |= G_CF_SPOILED;
1280 	return (g_post_event(g_media_changed_event, pp, flag, pp, NULL));
1281 }
1282 
1283 int
1284 g_media_gone(struct g_provider *pp, int flag)
1285 {
1286 	struct g_consumer *cp;
1287 
1288 	LIST_FOREACH(cp, &pp->consumers, consumers)
1289 		cp->flags |= G_CF_SPOILED;
1290 	return (g_post_event(g_spoil_event, pp, flag, pp, NULL));
1291 }
1292 
1293 int
1294 g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len)
1295 {
1296 	int error, i;
1297 
1298 	i = len;
1299 	error = g_io_getattr(attr, cp, &i, var);
1300 	if (error)
1301 		return (error);
1302 	if (i != len)
1303 		return (EINVAL);
1304 	return (0);
1305 }
1306 
1307 static int
1308 g_get_device_prefix_len(const char *name)
1309 {
1310 	int len;
1311 
1312 	if (strncmp(name, "ada", 3) == 0)
1313 		len = 3;
1314 	else if (strncmp(name, "ad", 2) == 0)
1315 		len = 2;
1316 	else
1317 		return (0);
1318 	if (name[len] < '0' || name[len] > '9')
1319 		return (0);
1320 	do {
1321 		len++;
1322 	} while (name[len] >= '0' && name[len] <= '9');
1323 	return (len);
1324 }
1325 
1326 int
1327 g_compare_names(const char *namea, const char *nameb)
1328 {
1329 	int deva, devb;
1330 
1331 	if (strcmp(namea, nameb) == 0)
1332 		return (1);
1333 	deva = g_get_device_prefix_len(namea);
1334 	if (deva == 0)
1335 		return (0);
1336 	devb = g_get_device_prefix_len(nameb);
1337 	if (devb == 0)
1338 		return (0);
1339 	if (strcmp(namea + deva, nameb + devb) == 0)
1340 		return (1);
1341 	return (0);
1342 }
1343 
1344 #if defined(DIAGNOSTIC) || defined(DDB)
1345 /*
1346  * This function walks the mesh and returns a non-zero integer if it
1347  * finds the argument pointer is an object. The return value indicates
1348  * which type of object it is believed to be. If topology is not locked,
1349  * this function is potentially dangerous, but we don't assert that the
1350  * topology lock is held when called from debugger.
1351  */
1352 int
1353 g_valid_obj(void const *ptr)
1354 {
1355 	struct g_class *mp;
1356 	struct g_geom *gp;
1357 	struct g_consumer *cp;
1358 	struct g_provider *pp;
1359 
1360 #ifdef KDB
1361 	if (kdb_active == 0)
1362 #endif
1363 		g_topology_assert();
1364 
1365 	LIST_FOREACH(mp, &g_classes, class) {
1366 		if (ptr == mp)
1367 			return (1);
1368 		LIST_FOREACH(gp, &mp->geom, geom) {
1369 			if (ptr == gp)
1370 				return (2);
1371 			LIST_FOREACH(cp, &gp->consumer, consumer)
1372 				if (ptr == cp)
1373 					return (3);
1374 			LIST_FOREACH(pp, &gp->provider, provider)
1375 				if (ptr == pp)
1376 					return (4);
1377 		}
1378 	}
1379 	return(0);
1380 }
1381 #endif
1382 
1383 #ifdef DDB
1384 
1385 #define	gprintf(...)	do {						\
1386 	db_printf("%*s", indent, "");					\
1387 	db_printf(__VA_ARGS__);						\
1388 } while (0)
1389 #define	gprintln(...)	do {						\
1390 	gprintf(__VA_ARGS__);						\
1391 	db_printf("\n");						\
1392 } while (0)
1393 
1394 #define	ADDFLAG(obj, flag, sflag)	do {				\
1395 	if ((obj)->flags & (flag)) {					\
1396 		if (comma)						\
1397 			strlcat(str, ",", size);			\
1398 		strlcat(str, (sflag), size);				\
1399 		comma = 1;						\
1400 	}								\
1401 } while (0)
1402 
1403 static char *
1404 provider_flags_to_string(struct g_provider *pp, char *str, size_t size)
1405 {
1406 	int comma = 0;
1407 
1408 	bzero(str, size);
1409 	if (pp->flags == 0) {
1410 		strlcpy(str, "NONE", size);
1411 		return (str);
1412 	}
1413 	ADDFLAG(pp, G_PF_WITHER, "G_PF_WITHER");
1414 	ADDFLAG(pp, G_PF_ORPHAN, "G_PF_ORPHAN");
1415 	return (str);
1416 }
1417 
1418 static char *
1419 geom_flags_to_string(struct g_geom *gp, char *str, size_t size)
1420 {
1421 	int comma = 0;
1422 
1423 	bzero(str, size);
1424 	if (gp->flags == 0) {
1425 		strlcpy(str, "NONE", size);
1426 		return (str);
1427 	}
1428 	ADDFLAG(gp, G_GEOM_WITHER, "G_GEOM_WITHER");
1429 	return (str);
1430 }
1431 static void
1432 db_show_geom_consumer(int indent, struct g_consumer *cp)
1433 {
1434 
1435 	if (indent == 0) {
1436 		gprintln("consumer: %p", cp);
1437 		gprintln("  class:    %s (%p)", cp->geom->class->name,
1438 		    cp->geom->class);
1439 		gprintln("  geom:     %s (%p)", cp->geom->name, cp->geom);
1440 		if (cp->provider == NULL)
1441 			gprintln("  provider: none");
1442 		else {
1443 			gprintln("  provider: %s (%p)", cp->provider->name,
1444 			    cp->provider);
1445 		}
1446 		gprintln("  access:   r%dw%de%d", cp->acr, cp->acw, cp->ace);
1447 		gprintln("  flags:    0x%04x", cp->flags);
1448 #ifdef INVARIANTS
1449 		gprintln("  nstart:   %u", cp->nstart);
1450 		gprintln("  nend:     %u", cp->nend);
1451 #endif
1452 	} else {
1453 		gprintf("consumer: %p (%s), access=r%dw%de%d", cp,
1454 		    cp->provider != NULL ? cp->provider->name : "none",
1455 		    cp->acr, cp->acw, cp->ace);
1456 		if (cp->flags)
1457 			db_printf(", flags=0x%04x", cp->flags);
1458 		db_printf("\n");
1459 	}
1460 }
1461 
1462 static void
1463 db_show_geom_provider(int indent, struct g_provider *pp)
1464 {
1465 	struct g_consumer *cp;
1466 	char flags[64];
1467 
1468 	if (indent == 0) {
1469 		gprintln("provider: %s (%p)", pp->name, pp);
1470 		gprintln("  class:        %s (%p)", pp->geom->class->name,
1471 		    pp->geom->class);
1472 		gprintln("  geom:         %s (%p)", pp->geom->name, pp->geom);
1473 		gprintln("  mediasize:    %jd", (intmax_t)pp->mediasize);
1474 		gprintln("  sectorsize:   %u", pp->sectorsize);
1475 		gprintln("  stripesize:   %ju", (uintmax_t)pp->stripesize);
1476 		gprintln("  stripeoffset: %ju", (uintmax_t)pp->stripeoffset);
1477 		gprintln("  access:       r%dw%de%d", pp->acr, pp->acw,
1478 		    pp->ace);
1479 		gprintln("  flags:        %s (0x%04x)",
1480 		    provider_flags_to_string(pp, flags, sizeof(flags)),
1481 		    pp->flags);
1482 		gprintln("  error:        %d", pp->error);
1483 		if (LIST_EMPTY(&pp->consumers))
1484 			gprintln("  consumers:    none");
1485 	} else {
1486 		gprintf("provider: %s (%p), access=r%dw%de%d",
1487 		    pp->name, pp, pp->acr, pp->acw, pp->ace);
1488 		if (pp->flags != 0) {
1489 			db_printf(", flags=%s (0x%04x)",
1490 			    provider_flags_to_string(pp, flags, sizeof(flags)),
1491 			    pp->flags);
1492 		}
1493 		db_printf("\n");
1494 	}
1495 	if (!LIST_EMPTY(&pp->consumers)) {
1496 		LIST_FOREACH(cp, &pp->consumers, consumers) {
1497 			db_show_geom_consumer(indent + 2, cp);
1498 			if (db_pager_quit)
1499 				break;
1500 		}
1501 	}
1502 }
1503 
1504 static void
1505 db_show_geom_geom(int indent, struct g_geom *gp)
1506 {
1507 	struct g_provider *pp;
1508 	struct g_consumer *cp;
1509 	char flags[64];
1510 
1511 	if (indent == 0) {
1512 		gprintln("geom: %s (%p)", gp->name, gp);
1513 		gprintln("  class:     %s (%p)", gp->class->name, gp->class);
1514 		gprintln("  flags:     %s (0x%04x)",
1515 		    geom_flags_to_string(gp, flags, sizeof(flags)), gp->flags);
1516 		gprintln("  rank:      %d", gp->rank);
1517 		if (LIST_EMPTY(&gp->provider))
1518 			gprintln("  providers: none");
1519 		if (LIST_EMPTY(&gp->consumer))
1520 			gprintln("  consumers: none");
1521 	} else {
1522 		gprintf("geom: %s (%p), rank=%d", gp->name, gp, gp->rank);
1523 		if (gp->flags != 0) {
1524 			db_printf(", flags=%s (0x%04x)",
1525 			    geom_flags_to_string(gp, flags, sizeof(flags)),
1526 			    gp->flags);
1527 		}
1528 		db_printf("\n");
1529 	}
1530 	if (!LIST_EMPTY(&gp->provider)) {
1531 		LIST_FOREACH(pp, &gp->provider, provider) {
1532 			db_show_geom_provider(indent + 2, pp);
1533 			if (db_pager_quit)
1534 				break;
1535 		}
1536 	}
1537 	if (!LIST_EMPTY(&gp->consumer)) {
1538 		LIST_FOREACH(cp, &gp->consumer, consumer) {
1539 			db_show_geom_consumer(indent + 2, cp);
1540 			if (db_pager_quit)
1541 				break;
1542 		}
1543 	}
1544 }
1545 
1546 static void
1547 db_show_geom_class(struct g_class *mp)
1548 {
1549 	struct g_geom *gp;
1550 
1551 	db_printf("class: %s (%p)\n", mp->name, mp);
1552 	LIST_FOREACH(gp, &mp->geom, geom) {
1553 		db_show_geom_geom(2, gp);
1554 		if (db_pager_quit)
1555 			break;
1556 	}
1557 }
1558 
1559 /*
1560  * Print the GEOM topology or the given object.
1561  */
1562 DB_SHOW_COMMAND(geom, db_show_geom)
1563 {
1564 	struct g_class *mp;
1565 
1566 	if (!have_addr) {
1567 		/* No address given, print the entire topology. */
1568 		LIST_FOREACH(mp, &g_classes, class) {
1569 			db_show_geom_class(mp);
1570 			db_printf("\n");
1571 			if (db_pager_quit)
1572 				break;
1573 		}
1574 	} else {
1575 		switch (g_valid_obj((void *)addr)) {
1576 		case 1:
1577 			db_show_geom_class((struct g_class *)addr);
1578 			break;
1579 		case 2:
1580 			db_show_geom_geom(0, (struct g_geom *)addr);
1581 			break;
1582 		case 3:
1583 			db_show_geom_consumer(0, (struct g_consumer *)addr);
1584 			break;
1585 		case 4:
1586 			db_show_geom_provider(0, (struct g_provider *)addr);
1587 			break;
1588 		default:
1589 			db_printf("Not a GEOM object.\n");
1590 			break;
1591 		}
1592 	}
1593 }
1594 
1595 static void
1596 db_print_bio_cmd(struct bio *bp)
1597 {
1598 	db_printf("  cmd: ");
1599 	switch (bp->bio_cmd) {
1600 	case BIO_READ: db_printf("BIO_READ"); break;
1601 	case BIO_WRITE: db_printf("BIO_WRITE"); break;
1602 	case BIO_DELETE: db_printf("BIO_DELETE"); break;
1603 	case BIO_GETATTR: db_printf("BIO_GETATTR"); break;
1604 	case BIO_FLUSH: db_printf("BIO_FLUSH"); break;
1605 	case BIO_CMD0: db_printf("BIO_CMD0"); break;
1606 	case BIO_CMD1: db_printf("BIO_CMD1"); break;
1607 	case BIO_CMD2: db_printf("BIO_CMD2"); break;
1608 	case BIO_ZONE: db_printf("BIO_ZONE"); break;
1609 	default: db_printf("UNKNOWN"); break;
1610 	}
1611 	db_printf("\n");
1612 }
1613 
1614 static void
1615 db_print_bio_flags(struct bio *bp)
1616 {
1617 	int comma;
1618 
1619 	comma = 0;
1620 	db_printf("  flags: ");
1621 	if (bp->bio_flags & BIO_ERROR) {
1622 		db_printf("BIO_ERROR");
1623 		comma = 1;
1624 	}
1625 	if (bp->bio_flags & BIO_DONE) {
1626 		db_printf("%sBIO_DONE", (comma ? ", " : ""));
1627 		comma = 1;
1628 	}
1629 	if (bp->bio_flags & BIO_ONQUEUE)
1630 		db_printf("%sBIO_ONQUEUE", (comma ? ", " : ""));
1631 	db_printf("\n");
1632 }
1633 
1634 /*
1635  * Print useful information in a BIO
1636  */
1637 DB_SHOW_COMMAND(bio, db_show_bio)
1638 {
1639 	struct bio *bp;
1640 
1641 	if (have_addr) {
1642 		bp = (struct bio *)addr;
1643 		db_printf("BIO %p\n", bp);
1644 		db_print_bio_cmd(bp);
1645 		db_print_bio_flags(bp);
1646 		db_printf("  cflags: 0x%hx\n", bp->bio_cflags);
1647 		db_printf("  pflags: 0x%hx\n", bp->bio_pflags);
1648 		db_printf("  offset: %jd\n", (intmax_t)bp->bio_offset);
1649 		db_printf("  length: %jd\n", (intmax_t)bp->bio_length);
1650 		db_printf("  bcount: %ld\n", bp->bio_bcount);
1651 		db_printf("  resid: %ld\n", bp->bio_resid);
1652 		db_printf("  completed: %jd\n", (intmax_t)bp->bio_completed);
1653 		db_printf("  children: %u\n", bp->bio_children);
1654 		db_printf("  inbed: %u\n", bp->bio_inbed);
1655 		db_printf("  error: %d\n", bp->bio_error);
1656 		db_printf("  parent: %p\n", bp->bio_parent);
1657 		db_printf("  driver1: %p\n", bp->bio_driver1);
1658 		db_printf("  driver2: %p\n", bp->bio_driver2);
1659 		db_printf("  caller1: %p\n", bp->bio_caller1);
1660 		db_printf("  caller2: %p\n", bp->bio_caller2);
1661 		db_printf("  bio_from: %p\n", bp->bio_from);
1662 		db_printf("  bio_to: %p\n", bp->bio_to);
1663 
1664 #if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING)
1665 		db_printf("  bio_track_bp: %p\n", bp->bio_track_bp);
1666 #endif
1667 	}
1668 }
1669 
1670 #undef	gprintf
1671 #undef	gprintln
1672 #undef	ADDFLAG
1673 
1674 #endif	/* DDB */
1675