xref: /freebsd/sys/geom/geom_subr.c (revision f9218d3d4fd34f082473b3a021c6d4d109fb47cf)
1 /*-
2  * Copyright (c) 2002 Poul-Henning Kamp
3  * Copyright (c) 2002 Networks Associates Technology, Inc.
4  * All rights reserved.
5  *
6  * This software was developed for the FreeBSD Project by Poul-Henning Kamp
7  * and NAI Labs, the Security Research Division of Network Associates, Inc.
8  * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
9  * DARPA CHATS research program.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. The names of the authors may not be used to endorse or promote
20  *    products derived from this software without specific prior written
21  *    permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  * $FreeBSD$
36  */
37 
38 
39 #include <sys/param.h>
40 #include <sys/stdint.h>
41 #ifndef _KERNEL
42 #include <stdio.h>
43 #include <unistd.h>
44 #include <stdlib.h>
45 #include <signal.h>
46 #include <string.h>
47 #include <err.h>
48 #else
49 #include <sys/systm.h>
50 #include <sys/kernel.h>
51 #include <sys/malloc.h>
52 #include <sys/bio.h>
53 #include <sys/sysctl.h>
54 #include <sys/proc.h>
55 #include <sys/kthread.h>
56 #include <sys/lock.h>
57 #include <sys/mutex.h>
58 #endif
59 #include <sys/errno.h>
60 #include <sys/sbuf.h>
61 #include <geom/geom.h>
62 #include <geom/geom_int.h>
63 #include <geom/geom_stats.h>
64 #include <machine/stdarg.h>
65 
66 struct class_list_head g_classes = LIST_HEAD_INITIALIZER(g_classes);
67 static struct g_tailq_head geoms = TAILQ_HEAD_INITIALIZER(geoms);
68 static int g_nproviders;
69 char *g_wait_event, *g_wait_up, *g_wait_down, *g_wait_sim;
70 
71 static int g_ignition;
72 
73 void
74 g_add_class(struct g_class *mp)
75 {
76 
77 	if (!g_ignition) {
78 		g_ignition++;
79 		g_init();
80 	}
81 	mp->protect = 0x020016600;
82 	g_topology_lock();
83 	g_trace(G_T_TOPOLOGY, "g_add_class(%s)", mp->name);
84 	LIST_INIT(&mp->geom);
85 	LIST_INSERT_HEAD(&g_classes, mp, class);
86 	if (g_nproviders > 0)
87 		g_post_event(EV_NEW_CLASS, mp, NULL, NULL, NULL);
88 	g_topology_unlock();
89 }
90 
91 struct g_geom *
92 g_new_geomf(struct g_class *mp, const char *fmt, ...)
93 {
94 	struct g_geom *gp;
95 	va_list ap;
96 	struct sbuf *sb;
97 
98 	g_topology_assert();
99 	va_start(ap, fmt);
100 	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
101 	sbuf_vprintf(sb, fmt, ap);
102 	sbuf_finish(sb);
103 	gp = g_malloc(sizeof *gp, M_WAITOK | M_ZERO);
104 	gp->protect = 0x020016601;
105 	gp->name = g_malloc(sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
106 	gp->class = mp;
107 	gp->rank = 1;
108 	LIST_INIT(&gp->consumer);
109 	LIST_INIT(&gp->provider);
110 	LIST_INSERT_HEAD(&mp->geom, gp, geom);
111 	TAILQ_INSERT_HEAD(&geoms, gp, geoms);
112 	strcpy(gp->name, sbuf_data(sb));
113 	sbuf_delete(sb);
114 	return (gp);
115 }
116 
117 void
118 g_destroy_geom(struct g_geom *gp)
119 {
120 
121 	g_trace(G_T_TOPOLOGY, "g_destroy_geom(%p(%s))", gp, gp->name);
122 	g_topology_assert();
123 	KASSERT(gp->event == NULL, ("g_destroy_geom() with event"));
124 	KASSERT(LIST_EMPTY(&gp->consumer),
125 	    ("g_destroy_geom(%s) with consumer(s) [%p]",
126 	    gp->name, LIST_FIRST(&gp->consumer)));
127 	KASSERT(LIST_EMPTY(&gp->provider),
128 	    ("g_destroy_geom(%s) with provider(s) [%p]",
129 	    gp->name, LIST_FIRST(&gp->consumer)));
130 	LIST_REMOVE(gp, geom);
131 	TAILQ_REMOVE(&geoms, gp, geoms);
132 	g_free(gp->name);
133 	g_free(gp);
134 }
135 
136 struct g_consumer *
137 g_new_consumer(struct g_geom *gp)
138 {
139 	struct g_consumer *cp;
140 
141 	g_topology_assert();
142 	KASSERT(gp->orphan != NULL,
143 	    ("g_new_consumer on geom(%s) (class %s) without orphan",
144 	    gp->name, gp->class->name));
145 
146 	cp = g_malloc(sizeof *cp, M_WAITOK | M_ZERO);
147 	cp->protect = 0x020016602;
148 	cp->geom = gp;
149 	cp->stat = g_stat_new(cp);
150 	LIST_INSERT_HEAD(&gp->consumer, cp, consumer);
151 	return(cp);
152 }
153 
154 void
155 g_destroy_consumer(struct g_consumer *cp)
156 {
157 
158 	g_trace(G_T_TOPOLOGY, "g_destroy_consumer(%p)", cp);
159 	g_topology_assert();
160 	KASSERT(cp->event == NULL, ("g_destroy_consumer() with event"));
161 	KASSERT (cp->provider == NULL, ("g_destroy_consumer but attached"));
162 	KASSERT (cp->acr == 0, ("g_destroy_consumer with acr"));
163 	KASSERT (cp->acw == 0, ("g_destroy_consumer with acw"));
164 	KASSERT (cp->ace == 0, ("g_destroy_consumer with ace"));
165 	LIST_REMOVE(cp, consumer);
166 	g_stat_delete(cp->stat);
167 	g_free(cp);
168 }
169 
170 struct g_provider *
171 g_new_providerf(struct g_geom *gp, const char *fmt, ...)
172 {
173 	struct g_provider *pp;
174 	struct sbuf *sb;
175 	va_list ap;
176 
177 	g_topology_assert();
178 	va_start(ap, fmt);
179 	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
180 	sbuf_vprintf(sb, fmt, ap);
181 	sbuf_finish(sb);
182 	pp = g_malloc(sizeof *pp + sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
183 	pp->protect = 0x020016603;
184 	pp->name = (char *)(pp + 1);
185 	strcpy(pp->name, sbuf_data(sb));
186 	sbuf_delete(sb);
187 	LIST_INIT(&pp->consumers);
188 	pp->error = ENXIO;
189 	pp->geom = gp;
190 	pp->stat = g_stat_new(pp);
191 	LIST_INSERT_HEAD(&gp->provider, pp, provider);
192 	g_nproviders++;
193 	g_post_event(EV_NEW_PROVIDER, NULL, NULL, pp, NULL);
194 	return (pp);
195 }
196 
197 void
198 g_error_provider(struct g_provider *pp, int error)
199 {
200 
201 	pp->error = error;
202 }
203 
204 
205 void
206 g_destroy_provider(struct g_provider *pp)
207 {
208 	struct g_geom *gp;
209 	struct g_consumer *cp;
210 
211 	g_topology_assert();
212 	KASSERT(pp->event == NULL, ("g_destroy_provider() with event"));
213 	KASSERT(LIST_EMPTY(&pp->consumers),
214 	    ("g_destroy_provider but attached"));
215 	KASSERT (pp->acr == 0, ("g_destroy_provider with acr"));
216 	KASSERT (pp->acw == 0, ("g_destroy_provider with acw"));
217 	KASSERT (pp->acw == 0, ("g_destroy_provider with ace"));
218 	g_nproviders--;
219 	LIST_REMOVE(pp, provider);
220 	gp = pp->geom;
221 	g_stat_delete(pp->stat);
222 	g_free(pp);
223 	if (!(gp->flags & G_GEOM_WITHER))
224 		return;
225 	if (!LIST_EMPTY(&gp->provider))
226 		return;
227 	for (;;) {
228 		cp = LIST_FIRST(&gp->consumer);
229 		if (cp == NULL)
230 			break;
231 		g_detach(cp);
232 		g_destroy_consumer(cp);
233 	}
234 	g_destroy_geom(gp);
235 }
236 
237 /*
238  * We keep the "geoms" list sorted by topological order (== increasing
239  * numerical rank) at all times.
240  * When an attach is done, the attaching geoms rank is invalidated
241  * and it is moved to the tail of the list.
242  * All geoms later in the sequence has their ranks reevaluated in
243  * sequence.  If we cannot assign rank to a geom because it's
244  * prerequisites do not have rank, we move that element to the tail
245  * of the sequence with invalid rank as well.
246  * At some point we encounter our original geom and if we stil fail
247  * to assign it a rank, there must be a loop and we fail back to
248  * g_attach() which detach again and calls redo_rank again
249  * to fix up the damage.
250  * It would be much simpler code wise to do it recursively, but we
251  * can't risk that on the kernel stack.
252  */
253 
254 static int
255 redo_rank(struct g_geom *gp)
256 {
257 	struct g_consumer *cp;
258 	struct g_geom *gp1, *gp2;
259 	int n, m;
260 
261 	g_topology_assert();
262 
263 	/* Invalidate this geoms rank and move it to the tail */
264 	gp1 = TAILQ_NEXT(gp, geoms);
265 	if (gp1 != NULL) {
266 		gp->rank = 0;
267 		TAILQ_REMOVE(&geoms, gp, geoms);
268 		TAILQ_INSERT_TAIL(&geoms, gp, geoms);
269 	} else {
270 		gp1 = gp;
271 	}
272 
273 	/* re-rank the rest of the sequence */
274 	for (; gp1 != NULL; gp1 = gp2) {
275 		gp1->rank = 0;
276 		m = 1;
277 		LIST_FOREACH(cp, &gp1->consumer, consumer) {
278 			if (cp->provider == NULL)
279 				continue;
280 			n = cp->provider->geom->rank;
281 			if (n == 0) {
282 				m = 0;
283 				break;
284 			} else if (n >= m)
285 				m = n + 1;
286 		}
287 		gp1->rank = m;
288 		gp2 = TAILQ_NEXT(gp1, geoms);
289 
290 		/* got a rank, moving on */
291 		if (m != 0)
292 			continue;
293 
294 		/* no rank to original geom means loop */
295 		if (gp == gp1)
296 			return (ELOOP);
297 
298 		/* no rank, put it at the end move on */
299 		TAILQ_REMOVE(&geoms, gp1, geoms);
300 		TAILQ_INSERT_TAIL(&geoms, gp1, geoms);
301 	}
302 	return (0);
303 }
304 
305 int
306 g_attach(struct g_consumer *cp, struct g_provider *pp)
307 {
308 	int error;
309 
310 	g_topology_assert();
311 	KASSERT(cp->provider == NULL, ("attach but attached"));
312 	cp->provider = pp;
313 	LIST_INSERT_HEAD(&pp->consumers, cp, consumers);
314 	error = redo_rank(cp->geom);
315 	if (error) {
316 		LIST_REMOVE(cp, consumers);
317 		cp->provider = NULL;
318 		redo_rank(cp->geom);
319 	}
320 	return (error);
321 }
322 
323 void
324 g_detach(struct g_consumer *cp)
325 {
326 	struct g_provider *pp;
327 
328 	g_trace(G_T_TOPOLOGY, "g_detach(%p)", cp);
329 	KASSERT(cp != (void*)0xd0d0d0d0, ("ARGH!"));
330 	g_topology_assert();
331 	KASSERT(cp->provider != NULL, ("detach but not attached"));
332 	KASSERT(cp->acr == 0, ("detach but nonzero acr"));
333 	KASSERT(cp->acw == 0, ("detach but nonzero acw"));
334 	KASSERT(cp->ace == 0, ("detach but nonzero ace"));
335 	KASSERT(cp->stat->nop == cp->stat->nend,
336 	    ("detach with active requests"));
337 	pp = cp->provider;
338 	LIST_REMOVE(cp, consumers);
339 	cp->provider = NULL;
340 	if (LIST_EMPTY(&pp->consumers)) {
341 		if (pp->geom->flags & G_GEOM_WITHER)
342 			g_destroy_provider(pp);
343 	}
344 	redo_rank(cp->geom);
345 }
346 
347 
348 /*
349  * g_access_abs()
350  *
351  * Access-check with absolute new values:  Just fall through
352  * and use the relative version.
353  */
354 int
355 g_access_abs(struct g_consumer *cp, int acr, int acw, int ace)
356 {
357 
358 	g_topology_assert();
359 	return(g_access_rel(cp,
360 		acr - cp->acr,
361 		acw - cp->acw,
362 		ace - cp->ace));
363 }
364 
365 /*
366  * g_access_rel()
367  *
368  * Access-check with delta values.  The question asked is "can provider
369  * "cp" change the access counters by the relative amounts dc[rwe] ?"
370  */
371 
372 int
373 g_access_rel(struct g_consumer *cp, int dcr, int dcw, int dce)
374 {
375 	struct g_provider *pp;
376 	int pr,pw,pe;
377 	int error;
378 
379 	pp = cp->provider;
380 
381 	g_trace(G_T_ACCESS, "g_access_rel(%p(%s), %d, %d, %d)",
382 	    cp, pp->name, dcr, dcw, dce);
383 
384 	g_topology_assert();
385 	KASSERT(cp->provider != NULL, ("access but not attached"));
386 	KASSERT(cp->acr + dcr >= 0, ("access resulting in negative acr"));
387 	KASSERT(cp->acw + dcw >= 0, ("access resulting in negative acw"));
388 	KASSERT(cp->ace + dce >= 0, ("access resulting in negative ace"));
389 	KASSERT(pp->geom->access != NULL, ("NULL geom->access"));
390 
391 	/*
392 	 * If our class cares about being spoiled, and we have been, we
393 	 * are probably just ahead of the event telling us that.  Fail
394 	 * now rather than having to unravel this later.
395 	 */
396 	if (cp->geom->spoiled != NULL && cp->spoiled) {
397 		KASSERT(dcr >= 0, ("spoiled but dcr = %d", dcr));
398 		KASSERT(dcw >= 0, ("spoiled but dce = %d", dcw));
399 		KASSERT(dce >= 0, ("spoiled but dcw = %d", dce));
400 		KASSERT(cp->acr == 0, ("spoiled but cp->acr = %d", cp->acr));
401 		KASSERT(cp->acw == 0, ("spoiled but cp->acw = %d", cp->acw));
402 		KASSERT(cp->ace == 0, ("spoiled but cp->ace = %d", cp->ace));
403 		return(ENXIO);
404 	}
405 
406 	/*
407 	 * Figure out what counts the provider would have had, if this
408 	 * consumer had (r0w0e0) at this time.
409 	 */
410 	pr = pp->acr - cp->acr;
411 	pw = pp->acw - cp->acw;
412 	pe = pp->ace - cp->ace;
413 
414 	g_trace(G_T_ACCESS,
415     "open delta:[r%dw%de%d] old:[r%dw%de%d] provider:[r%dw%de%d] %p(%s)",
416 	    dcr, dcw, dce,
417 	    cp->acr, cp->acw, cp->ace,
418 	    pp->acr, pp->acw, pp->ace,
419 	    pp, pp->name);
420 
421 	/* If foot-shooting is enabled, any open on rank#1 is OK */
422 	if ((g_debugflags & 16) && pp->geom->rank == 1)
423 		;
424 	/* If we try exclusive but already write: fail */
425 	else if (dce > 0 && pw > 0)
426 		return (EPERM);
427 	/* If we try write but already exclusive: fail */
428 	else if (dcw > 0 && pe > 0)
429 		return (EPERM);
430 	/* If we try to open more but provider is error'ed: fail */
431 	else if ((dcr > 0 || dcw > 0 || dce > 0) && pp->error != 0)
432 		return (pp->error);
433 
434 	/* Ok then... */
435 
436 	/*
437 	 * If we open first write, spoil any partner consumers.
438 	 * If we close last write, trigger re-taste.
439 	 */
440 	if (pp->acw == 0 && dcw != 0)
441 		g_spoil(pp, cp);
442 	else if (pp->acw != 0 && pp->acw == -dcw &&
443 	    !(pp->geom->flags & G_GEOM_WITHER))
444 		g_post_event(EV_NEW_PROVIDER, NULL, NULL, pp, NULL);
445 
446 	error = pp->geom->access(pp, dcr, dcw, dce);
447 	if (!error) {
448 		pp->acr += dcr;
449 		pp->acw += dcw;
450 		pp->ace += dce;
451 		cp->acr += dcr;
452 		cp->acw += dcw;
453 		cp->ace += dce;
454 	}
455 	return (error);
456 }
457 
458 int
459 g_handleattr_int(struct bio *bp, const char *attribute, int val)
460 {
461 
462 	return (g_handleattr(bp, attribute, &val, sizeof val));
463 }
464 
465 int
466 g_handleattr_off_t(struct bio *bp, const char *attribute, off_t val)
467 {
468 
469 	return (g_handleattr(bp, attribute, &val, sizeof val));
470 }
471 
472 
473 int
474 g_handleattr(struct bio *bp, const char *attribute, void *val, int len)
475 {
476 	int error;
477 
478 	if (strcmp(bp->bio_attribute, attribute))
479 		return (0);
480 	if (bp->bio_length != len) {
481 		printf("bio_length %jd len %d -> EFAULT\n",
482 		    (intmax_t)bp->bio_length, len);
483 		error = EFAULT;
484 	} else {
485 		error = 0;
486 		bcopy(val, bp->bio_data, len);
487 		bp->bio_completed = len;
488 	}
489 	g_io_deliver(bp, error);
490 	return (1);
491 }
492 
493 int
494 g_std_access(struct g_provider *pp __unused,
495 	int dr __unused, int dw __unused, int de __unused)
496 {
497 
498         return (0);
499 }
500 
501 void
502 g_std_done(struct bio *bp)
503 {
504 	struct bio *bp2;
505 
506 	bp2 = bp->bio_parent;
507 	if (bp2->bio_error == 0)
508 		bp2->bio_error = bp->bio_error;
509 	bp2->bio_completed += bp->bio_completed;
510 	g_destroy_bio(bp);
511 	bp2->bio_inbed++;
512 	if (bp2->bio_children == bp2->bio_inbed)
513 		g_io_deliver(bp2, bp2->bio_error);
514 }
515 
516 /* XXX: maybe this is only g_slice_spoiled */
517 
518 void
519 g_std_spoiled(struct g_consumer *cp)
520 {
521 	struct g_geom *gp;
522 	struct g_provider *pp;
523 
524 	g_trace(G_T_TOPOLOGY, "g_std_spoiled(%p)", cp);
525 	g_topology_assert();
526 	g_detach(cp);
527 	gp = cp->geom;
528 	LIST_FOREACH(pp, &gp->provider, provider)
529 		g_orphan_provider(pp, ENXIO);
530 	g_destroy_consumer(cp);
531 	if (LIST_EMPTY(&gp->provider) && LIST_EMPTY(&gp->consumer))
532 		g_destroy_geom(gp);
533 	else
534 		gp->flags |= G_GEOM_WITHER;
535 }
536 
537 /*
538  * Spoiling happens when a provider is opened for writing, but consumers
539  * which are configured by in-band data are attached (slicers for instance).
540  * Since the write might potentially change the in-band data, such consumers
541  * need to re-evaluate their existence after the writing session closes.
542  * We do this by (offering to) tear them down when the open for write happens
543  * in return for a re-taste when it closes again.
544  * Together with the fact that such consumers grab an 'e' bit whenever they
545  * are open, regardless of mode, this ends up DTRT.
546  */
547 
548 void
549 g_spoil(struct g_provider *pp, struct g_consumer *cp)
550 {
551 	struct g_consumer *cp2;
552 
553 	g_topology_assert();
554 
555 	if (!strcmp(pp->name, "geom.ctl"))
556 		return;
557 	LIST_FOREACH(cp2, &pp->consumers, consumers) {
558 		if (cp2 == cp)
559 			continue;
560 /*
561 		KASSERT(cp2->acr == 0, ("spoiling cp->acr = %d", cp2->acr));
562 		KASSERT(cp2->acw == 0, ("spoiling cp->acw = %d", cp2->acw));
563 */
564 		KASSERT(cp2->ace == 0, ("spoiling cp->ace = %d", cp2->ace));
565 		cp2->spoiled++;
566 	}
567 	g_post_event(EV_SPOILED, NULL, NULL, pp, cp);
568 }
569 
570 static struct g_class *
571 g_class_by_name(const char *name)
572 {
573 	struct g_class *mp;
574 
575 	g_trace(G_T_TOPOLOGY, "g_class_by_name(%s)", name);
576 	g_topology_assert();
577 	LIST_FOREACH(mp, &g_classes, class)
578 		if (!strcmp(mp->name, name))
579 			return (mp);
580 	return (NULL);
581 }
582 
583 struct g_geom *
584 g_insert_geom(const char *class, struct g_consumer *cp)
585 {
586 	struct g_class *mp;
587 	struct g_geom *gp;
588 	struct g_provider *pp, *pp2;
589 	struct g_consumer *cp2;
590 	int error;
591 
592 	g_trace(G_T_TOPOLOGY, "g_insert_geomf(%s, %p)", class, cp);
593 	g_topology_assert();
594 	KASSERT(cp->provider != NULL, ("g_insert_geomf but not attached"));
595 	/* XXX: check for events ?? */
596 	mp = g_class_by_name(class);
597 	if (mp == NULL)
598 		return (NULL);
599 	if (mp->config == NULL)
600 		return (NULL);
601 	pp = cp->provider;
602 	gp = mp->taste(mp, pp, G_TF_TRANSPARENT);
603 	if (gp == NULL)
604 		return (NULL);
605 	pp2 = LIST_FIRST(&gp->provider);
606 	cp2 = LIST_FIRST(&gp->consumer);
607 	cp2->acr += pp->acr;
608 	cp2->acw += pp->acw;
609 	cp2->ace += pp->ace;
610 	pp2->acr += pp->acr;
611 	pp2->acw += pp->acw;
612 	pp2->ace += pp->ace;
613 	LIST_REMOVE(cp, consumers);
614 	LIST_INSERT_HEAD(&pp2->consumers, cp, consumers);
615 	cp->provider = pp2;
616 	error = redo_rank(gp);
617 	KASSERT(error == 0, ("redo_rank failed in g_insert_geom"));
618 	return (gp);
619 }
620 
621 int
622 g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len)
623 {
624 	int error, i;
625 
626 	i = len;
627 	error = g_io_getattr(attr, cp, &i, var);
628 	if (error)
629 		return (error);
630 	if (i != len)
631 		return (EINVAL);
632 	return (0);
633 }
634 
635 /*
636  * Check if the given pointer is a live object
637  */
638 
639 void
640 g_sanity(void *ptr)
641 {
642 	struct g_class *mp;
643 	struct g_geom *gp;
644 	struct g_consumer *cp;
645 	struct g_provider *pp;
646 
647 	if (!(g_debugflags & 0x8))
648 		return;
649 	LIST_FOREACH(mp, &g_classes, class) {
650 		KASSERT(mp != ptr, ("Ptr is live class"));
651 		KASSERT(mp->protect == 0x20016600,
652 		    ("corrupt class %p %x", mp, mp->protect));
653 		LIST_FOREACH(gp, &mp->geom, geom) {
654 			KASSERT(gp != ptr, ("Ptr is live geom"));
655 			KASSERT(gp->protect == 0x20016601,
656 			    ("corrupt geom, %p %x", gp, gp->protect));
657 			KASSERT(gp->name != ptr, ("Ptr is live geom's name"));
658 			LIST_FOREACH(cp, &gp->consumer, consumer) {
659 				KASSERT(cp != ptr, ("Ptr is live consumer"));
660 				KASSERT(cp->protect == 0x20016602,
661 				    ("corrupt consumer %p %x",
662 				    cp, cp->protect));
663 			}
664 			LIST_FOREACH(pp, &gp->provider, provider) {
665 				KASSERT(pp != ptr, ("Ptr is live provider"));
666 				KASSERT(pp->protect == 0x20016603,
667 				    ("corrupt provider %p %x",
668 				    pp, pp->protect));
669 			}
670 		}
671 	}
672 }
673 
674 #ifdef _KERNEL
675 struct g_class *
676 g_idclass(struct geomidorname *p)
677 {
678 	struct g_class *mp;
679 	char *n;
680 
681 	if (p->len == 0) {
682 		LIST_FOREACH(mp, &g_classes, class)
683 			if ((uintptr_t)mp == p->u.id)
684 				return (mp);
685 		return (NULL);
686 	}
687 	n = g_malloc(p->len + 1, M_WAITOK);
688 	if (copyin(p->u.name, n, p->len) == 0) {
689 		n[p->len] = '\0';
690 		LIST_FOREACH(mp, &g_classes, class)
691 			if (!bcmp(n, mp->name, p->len + 1)) {
692 				g_free(n);
693 				return (mp);
694 			}
695 	}
696 	g_free(n);
697 	return (NULL);
698 }
699 
700 struct g_geom *
701 g_idgeom(struct geomidorname *p)
702 {
703 	struct g_class *mp;
704 	struct g_geom *gp;
705 	char *n;
706 
707 	if (p->len == 0) {
708 		LIST_FOREACH(mp, &g_classes, class)
709 			LIST_FOREACH(gp, &mp->geom, geom)
710 				if ((uintptr_t)gp == p->u.id)
711 					return (gp);
712 		return (NULL);
713 	}
714 	n = g_malloc(p->len + 1, M_WAITOK);
715 	if (copyin(p->u.name, n, p->len) == 0) {
716 		n[p->len] = '\0';
717 		LIST_FOREACH(mp, &g_classes, class)
718 			LIST_FOREACH(gp, &mp->geom, geom)
719 				if (!bcmp(n, gp->name, p->len + 1)) {
720 					g_free(n);
721 					return (gp);
722 				}
723 	}
724 	g_free(n);
725 	return (NULL);
726 }
727 
728 struct g_provider *
729 g_idprovider(struct geomidorname *p)
730 {
731 	struct g_class *mp;
732 	struct g_geom *gp;
733 	struct g_provider *pp;
734 	char *n;
735 
736 	if (p->len == 0) {
737 		LIST_FOREACH(mp, &g_classes, class)
738 			LIST_FOREACH(gp, &mp->geom, geom)
739 				LIST_FOREACH(pp, &gp->provider, provider)
740 					if ((uintptr_t)pp == p->u.id)
741 						return (pp);
742 		return (NULL);
743 	}
744 	n = g_malloc(p->len + 1, M_WAITOK);
745 	if (copyin(p->u.name, n, p->len) == 0) {
746 		n[p->len] = '\0';
747 		LIST_FOREACH(mp, &g_classes, class)
748 			LIST_FOREACH(gp, &mp->geom, geom)
749 				LIST_FOREACH(pp, &gp->provider, provider)
750 					if (!bcmp(n, pp->name, p->len + 1)) {
751 						g_free(n);
752 						return (pp);
753 					}
754 	}
755 	g_free(n);
756 	return (NULL);
757 }
758 #endif /* _KERNEL */
759