xref: /freebsd/sys/geom/mountver/g_mountver.c (revision cd0d51baaa4509a1db83251a601d34404d20c990)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2010 Edward Tomasz Napierala <trasz@FreeBSD.org>
5  * Copyright (c) 2004-2006 Pawel Jakub Dawidek <pjd@FreeBSD.org>
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
36 #include <sys/module.h>
37 #include <sys/lock.h>
38 #include <sys/mutex.h>
39 #include <sys/bio.h>
40 #include <sys/disk.h>
41 #include <sys/proc.h>
42 #include <sys/sbuf.h>
43 #include <sys/sysctl.h>
44 #include <sys/malloc.h>
45 #include <sys/eventhandler.h>
46 #include <geom/geom.h>
47 #include <geom/geom_dbg.h>
48 #include <geom/mountver/g_mountver.h>
49 
50 
51 SYSCTL_DECL(_kern_geom);
52 static SYSCTL_NODE(_kern_geom, OID_AUTO, mountver, CTLFLAG_RW,
53     0, "GEOM_MOUNTVER stuff");
54 static u_int g_mountver_debug = 0;
55 static u_int g_mountver_check_ident = 1;
56 SYSCTL_UINT(_kern_geom_mountver, OID_AUTO, debug, CTLFLAG_RW,
57     &g_mountver_debug, 0, "Debug level");
58 SYSCTL_UINT(_kern_geom_mountver, OID_AUTO, check_ident, CTLFLAG_RW,
59     &g_mountver_check_ident, 0, "Check disk ident when reattaching");
60 
61 static eventhandler_tag g_mountver_pre_sync = NULL;
62 
63 static void g_mountver_queue(struct bio *bp);
64 static void g_mountver_orphan(struct g_consumer *cp);
65 static void g_mountver_resize(struct g_consumer *cp);
66 static int g_mountver_destroy(struct g_geom *gp, boolean_t force);
67 static g_taste_t g_mountver_taste;
68 static int g_mountver_destroy_geom(struct gctl_req *req, struct g_class *mp,
69     struct g_geom *gp);
70 static void g_mountver_config(struct gctl_req *req, struct g_class *mp,
71     const char *verb);
72 static void g_mountver_dumpconf(struct sbuf *sb, const char *indent,
73     struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp);
74 static void g_mountver_init(struct g_class *mp);
75 static void g_mountver_fini(struct g_class *mp);
76 
77 struct g_class g_mountver_class = {
78 	.name = G_MOUNTVER_CLASS_NAME,
79 	.version = G_VERSION,
80 	.ctlreq = g_mountver_config,
81 	.taste = g_mountver_taste,
82 	.destroy_geom = g_mountver_destroy_geom,
83 	.init = g_mountver_init,
84 	.fini = g_mountver_fini
85 };
86 
87 static void
88 g_mountver_detach(void *arg, int flags __unused)
89 {
90 	struct g_consumer *cp = arg;
91 
92 	g_topology_assert();
93 	if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
94 		g_access(cp, -cp->acr, -cp->acw, -cp->ace);
95 	g_detach(cp);
96 }
97 
98 static void
99 g_mountver_done(struct bio *bp)
100 {
101 	struct g_mountver_softc *sc;
102 	struct g_geom *gp;
103 	struct g_consumer *cp;
104 	struct bio *pbp;
105 
106 	cp = bp->bio_from;
107 	gp = cp->geom;
108 	if (bp->bio_error != ENXIO) {
109 		g_std_done(bp);
110 		goto done;
111 	}
112 
113 	/*
114 	 * When the device goes away, it's possible that few requests
115 	 * will be completed with ENXIO before g_mountver_orphan()
116 	 * gets called.  To work around that, we have to queue requests
117 	 * that failed with ENXIO, in order to send them later.
118 	 */
119 	pbp = bp->bio_parent;
120 	KASSERT(pbp->bio_to == LIST_FIRST(&gp->provider),
121 	    ("parent request was for someone else"));
122 	g_destroy_bio(bp);
123 	pbp->bio_inbed++;
124 	g_mountver_queue(pbp);
125 
126 done:
127 	sc = gp->softc;
128 	mtx_lock(&sc->sc_mtx);
129 	if (--cp->index == 0 && sc->sc_orphaned)
130 		g_post_event(g_mountver_detach, cp, M_NOWAIT, NULL);
131 	mtx_unlock(&sc->sc_mtx);
132 }
133 
134 /*
135  * Send the BIO down.  The function is called with sc_mtx held to cover
136  * the race with orphan, but drops it before external calls.
137  */
138 static void
139 g_mountver_send(struct g_geom *gp, struct bio *bp)
140 {
141 	struct g_mountver_softc *sc = gp->softc;
142 	struct g_consumer *cp;
143 	struct bio *cbp;
144 
145 	mtx_assert(&sc->sc_mtx, MA_OWNED);
146 	cbp = g_clone_bio(bp);
147 	if (cbp == NULL) {
148 		mtx_unlock(&sc->sc_mtx);
149 		g_io_deliver(bp, ENOMEM);
150 		return;
151 	}
152 	cp = LIST_FIRST(&gp->consumer);
153 	cp->index++;
154 	mtx_unlock(&sc->sc_mtx);
155 
156 	cbp->bio_done = g_mountver_done;
157 	g_io_request(cbp, cp);
158 }
159 
160 static void
161 g_mountver_queue(struct bio *bp)
162 {
163 	struct g_mountver_softc *sc;
164 	struct g_geom *gp;
165 
166 	gp = bp->bio_to->geom;
167 	sc = gp->softc;
168 
169 	mtx_lock(&sc->sc_mtx);
170 	TAILQ_INSERT_TAIL(&sc->sc_queue, bp, bio_queue);
171 	mtx_unlock(&sc->sc_mtx);
172 }
173 
174 static void
175 g_mountver_send_queued(struct g_geom *gp)
176 {
177 	struct g_mountver_softc *sc;
178 	struct bio *bp;
179 
180 	sc = gp->softc;
181 
182 	mtx_lock(&sc->sc_mtx);
183 	while ((bp = TAILQ_FIRST(&sc->sc_queue)) != NULL && !sc->sc_orphaned) {
184 		TAILQ_REMOVE(&sc->sc_queue, bp, bio_queue);
185 		G_MOUNTVER_LOGREQ(bp, "Sending queued request.");
186 		/* sc_mtx is dropped inside */
187 		g_mountver_send(gp, bp);
188 		mtx_lock(&sc->sc_mtx);
189 	}
190 	mtx_unlock(&sc->sc_mtx);
191 }
192 
193 static void
194 g_mountver_discard_queued(struct g_geom *gp)
195 {
196 	struct g_mountver_softc *sc;
197 	struct bio *bp;
198 
199 	sc = gp->softc;
200 
201 	mtx_lock(&sc->sc_mtx);
202 	while ((bp = TAILQ_FIRST(&sc->sc_queue)) != NULL) {
203 		TAILQ_REMOVE(&sc->sc_queue, bp, bio_queue);
204 		mtx_unlock(&sc->sc_mtx);
205 		G_MOUNTVER_LOGREQ(bp, "Discarding queued request.");
206 		g_io_deliver(bp, ENXIO);
207 		mtx_lock(&sc->sc_mtx);
208 	}
209 	mtx_unlock(&sc->sc_mtx);
210 }
211 
212 static void
213 g_mountver_start(struct bio *bp)
214 {
215 	struct g_mountver_softc *sc;
216 	struct g_geom *gp;
217 
218 	gp = bp->bio_to->geom;
219 	sc = gp->softc;
220 	G_MOUNTVER_LOGREQ(bp, "Request received.");
221 
222 	/*
223 	 * It is possible that some bios were returned with ENXIO, even though
224 	 * orphaning didn't happen yet.  In that case, queue all subsequent
225 	 * requests in order to maintain ordering.
226 	 */
227 	mtx_lock(&sc->sc_mtx);
228 	if (sc->sc_orphaned || !TAILQ_EMPTY(&sc->sc_queue)) {
229 		mtx_unlock(&sc->sc_mtx);
230 		if (sc->sc_shutting_down) {
231 			G_MOUNTVER_LOGREQ(bp, "Discarding request due to shutdown.");
232 			g_io_deliver(bp, ENXIO);
233 			return;
234 		}
235 		G_MOUNTVER_LOGREQ(bp, "Queueing request.");
236 		g_mountver_queue(bp);
237 		if (!sc->sc_orphaned)
238 			g_mountver_send_queued(gp);
239 	} else {
240 		G_MOUNTVER_LOGREQ(bp, "Sending request.");
241 		/* sc_mtx is dropped inside */
242 		g_mountver_send(gp, bp);
243 	}
244 }
245 
246 static int
247 g_mountver_access(struct g_provider *pp, int dr, int dw, int de)
248 {
249 	struct g_mountver_softc *sc;
250 	struct g_geom *gp;
251 	struct g_consumer *cp;
252 
253 	g_topology_assert();
254 
255 	gp = pp->geom;
256 	cp = LIST_FIRST(&gp->consumer);
257 	sc = gp->softc;
258 	if (sc == NULL && dr <= 0 && dw <= 0 && de <= 0)
259 		return (0);
260 	KASSERT(sc != NULL, ("Trying to access withered provider \"%s\".", pp->name));
261 
262 	sc->sc_access_r += dr;
263 	sc->sc_access_w += dw;
264 	sc->sc_access_e += de;
265 
266 	if (sc->sc_orphaned)
267 		return (0);
268 
269 	return (g_access(cp, dr, dw, de));
270 }
271 
272 static int
273 g_mountver_create(struct gctl_req *req, struct g_class *mp, struct g_provider *pp)
274 {
275 	struct g_mountver_softc *sc;
276 	struct g_geom *gp;
277 	struct g_provider *newpp;
278 	struct g_consumer *cp;
279 	char name[64];
280 	int error;
281 	int identsize = DISK_IDENT_SIZE;
282 
283 	g_topology_assert();
284 
285 	gp = NULL;
286 	newpp = NULL;
287 	cp = NULL;
288 
289 	snprintf(name, sizeof(name), "%s%s", pp->name, G_MOUNTVER_SUFFIX);
290 	LIST_FOREACH(gp, &mp->geom, geom) {
291 		if (strcmp(gp->name, name) == 0) {
292 			gctl_error(req, "Provider %s already exists.", name);
293 			return (EEXIST);
294 		}
295 	}
296 	gp = g_new_geomf(mp, "%s", name);
297 	sc = g_malloc(sizeof(*sc), M_WAITOK | M_ZERO);
298 	mtx_init(&sc->sc_mtx, "gmountver", NULL, MTX_DEF | MTX_RECURSE);
299 	TAILQ_INIT(&sc->sc_queue);
300 	sc->sc_provider_name = strdup(pp->name, M_GEOM);
301 	gp->softc = sc;
302 	gp->start = g_mountver_start;
303 	gp->orphan = g_mountver_orphan;
304 	gp->resize = g_mountver_resize;
305 	gp->access = g_mountver_access;
306 	gp->dumpconf = g_mountver_dumpconf;
307 
308 	newpp = g_new_providerf(gp, "%s", gp->name);
309 	newpp->mediasize = pp->mediasize;
310 	newpp->sectorsize = pp->sectorsize;
311 	newpp->flags |= G_PF_DIRECT_SEND | G_PF_DIRECT_RECEIVE;
312 
313 	if ((pp->flags & G_PF_ACCEPT_UNMAPPED) != 0) {
314 		G_MOUNTVER_DEBUG(0, "Unmapped supported for %s.", gp->name);
315 		newpp->flags |= G_PF_ACCEPT_UNMAPPED;
316 	} else {
317 		G_MOUNTVER_DEBUG(0, "Unmapped unsupported for %s.", gp->name);
318 		newpp->flags &= ~G_PF_ACCEPT_UNMAPPED;
319 	}
320 
321 	cp = g_new_consumer(gp);
322 	cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE;
323 	error = g_attach(cp, pp);
324 	if (error != 0) {
325 		gctl_error(req, "Cannot attach to provider %s.", pp->name);
326 		goto fail;
327 	}
328 	error = g_access(cp, 1, 0, 0);
329 	if (error != 0) {
330 		gctl_error(req, "Cannot access provider %s.", pp->name);
331 		goto fail;
332 	}
333 	error = g_io_getattr("GEOM::ident", cp, &identsize, sc->sc_ident);
334 	g_access(cp, -1, 0, 0);
335 	if (error != 0) {
336 		if (g_mountver_check_ident) {
337 			gctl_error(req, "Cannot get disk ident from %s; error = %d.", pp->name, error);
338 			goto fail;
339 		}
340 
341 		G_MOUNTVER_DEBUG(0, "Cannot get disk ident from %s; error = %d.", pp->name, error);
342 		sc->sc_ident[0] = '\0';
343 	}
344 
345 	g_error_provider(newpp, 0);
346 	G_MOUNTVER_DEBUG(0, "Device %s created.", gp->name);
347 	return (0);
348 fail:
349 	g_free(sc->sc_provider_name);
350 	if (cp->provider != NULL)
351 		g_detach(cp);
352 	g_destroy_consumer(cp);
353 	g_destroy_provider(newpp);
354 	g_free(gp->softc);
355 	g_destroy_geom(gp);
356 	return (error);
357 }
358 
359 static int
360 g_mountver_destroy(struct g_geom *gp, boolean_t force)
361 {
362 	struct g_mountver_softc *sc;
363 	struct g_provider *pp;
364 
365 	g_topology_assert();
366 	if (gp->softc == NULL)
367 		return (ENXIO);
368 	sc = gp->softc;
369 	pp = LIST_FIRST(&gp->provider);
370 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
371 		if (force) {
372 			G_MOUNTVER_DEBUG(0, "Device %s is still open, so it "
373 			    "can't be definitely removed.", pp->name);
374 		} else {
375 			G_MOUNTVER_DEBUG(1, "Device %s is still open (r%dw%de%d).",
376 			    pp->name, pp->acr, pp->acw, pp->ace);
377 			return (EBUSY);
378 		}
379 	} else {
380 		G_MOUNTVER_DEBUG(0, "Device %s removed.", gp->name);
381 	}
382 	if (pp != NULL)
383 		g_wither_provider(pp, ENXIO);
384 	g_mountver_discard_queued(gp);
385 	g_free(sc->sc_provider_name);
386 	g_free(gp->softc);
387 	gp->softc = NULL;
388 	g_wither_geom(gp, ENXIO);
389 
390 	return (0);
391 }
392 
393 static int
394 g_mountver_destroy_geom(struct gctl_req *req, struct g_class *mp, struct g_geom *gp)
395 {
396 
397 	return (g_mountver_destroy(gp, 0));
398 }
399 
400 static void
401 g_mountver_ctl_create(struct gctl_req *req, struct g_class *mp)
402 {
403 	struct g_provider *pp;
404 	const char *name;
405 	char param[16];
406 	int i, *nargs;
407 
408 	g_topology_assert();
409 
410 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
411 	if (nargs == NULL) {
412 		gctl_error(req, "No '%s' argument", "nargs");
413 		return;
414 	}
415 	if (*nargs <= 0) {
416 		gctl_error(req, "Missing device(s).");
417 		return;
418 	}
419 	for (i = 0; i < *nargs; i++) {
420 		snprintf(param, sizeof(param), "arg%d", i);
421 		name = gctl_get_asciiparam(req, param);
422 		if (name == NULL) {
423 			gctl_error(req, "No 'arg%d' argument", i);
424 			return;
425 		}
426 		if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
427 			name += strlen("/dev/");
428 		pp = g_provider_by_name(name);
429 		if (pp == NULL) {
430 			G_MOUNTVER_DEBUG(1, "Provider %s is invalid.", name);
431 			gctl_error(req, "Provider %s is invalid.", name);
432 			return;
433 		}
434 		if (g_mountver_create(req, mp, pp) != 0)
435 			return;
436 	}
437 }
438 
439 static struct g_geom *
440 g_mountver_find_geom(struct g_class *mp, const char *name)
441 {
442 	struct g_geom *gp;
443 
444 	LIST_FOREACH(gp, &mp->geom, geom) {
445 		if (strcmp(gp->name, name) == 0)
446 			return (gp);
447 	}
448 	return (NULL);
449 }
450 
451 static void
452 g_mountver_ctl_destroy(struct gctl_req *req, struct g_class *mp)
453 {
454 	int *nargs, *force, error, i;
455 	struct g_geom *gp;
456 	const char *name;
457 	char param[16];
458 
459 	g_topology_assert();
460 
461 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
462 	if (nargs == NULL) {
463 		gctl_error(req, "No '%s' argument", "nargs");
464 		return;
465 	}
466 	if (*nargs <= 0) {
467 		gctl_error(req, "Missing device(s).");
468 		return;
469 	}
470 	force = gctl_get_paraml(req, "force", sizeof(*force));
471 	if (force == NULL) {
472 		gctl_error(req, "No 'force' argument");
473 		return;
474 	}
475 
476 	for (i = 0; i < *nargs; i++) {
477 		snprintf(param, sizeof(param), "arg%d", i);
478 		name = gctl_get_asciiparam(req, param);
479 		if (name == NULL) {
480 			gctl_error(req, "No 'arg%d' argument", i);
481 			return;
482 		}
483 		if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
484 			name += strlen("/dev/");
485 		gp = g_mountver_find_geom(mp, name);
486 		if (gp == NULL) {
487 			G_MOUNTVER_DEBUG(1, "Device %s is invalid.", name);
488 			gctl_error(req, "Device %s is invalid.", name);
489 			return;
490 		}
491 		error = g_mountver_destroy(gp, *force);
492 		if (error != 0) {
493 			gctl_error(req, "Cannot destroy device %s (error=%d).",
494 			    gp->name, error);
495 			return;
496 		}
497 	}
498 }
499 
500 static void
501 g_mountver_orphan(struct g_consumer *cp)
502 {
503 	struct g_mountver_softc *sc;
504 	int done;
505 
506 	g_topology_assert();
507 
508 	sc = cp->geom->softc;
509 	mtx_lock(&sc->sc_mtx);
510 	sc->sc_orphaned = 1;
511 	done = (cp->index == 0);
512 	mtx_unlock(&sc->sc_mtx);
513 	if (done)
514 		g_mountver_detach(cp, 0);
515 	G_MOUNTVER_DEBUG(0, "%s is offline.  Mount verification in progress.", sc->sc_provider_name);
516 }
517 
518 static void
519 g_mountver_resize(struct g_consumer *cp)
520 {
521 	struct g_geom *gp;
522 	struct g_provider *pp;
523 
524 	gp = cp->geom;
525 
526 	LIST_FOREACH(pp, &gp->provider, provider)
527 		g_resize_provider(pp, cp->provider->mediasize);
528 }
529 
530 static int
531 g_mountver_ident_matches(struct g_geom *gp)
532 {
533 	struct g_consumer *cp;
534 	struct g_mountver_softc *sc;
535 	char ident[DISK_IDENT_SIZE];
536 	int error, identsize = DISK_IDENT_SIZE;
537 
538 	sc = gp->softc;
539 	cp = LIST_FIRST(&gp->consumer);
540 
541 	if (g_mountver_check_ident == 0)
542 		return (0);
543 
544 	error = g_access(cp, 1, 0, 0);
545 	if (error != 0) {
546 		G_MOUNTVER_DEBUG(0, "Cannot access %s; "
547 		    "not attaching; error = %d.", gp->name, error);
548 		return (1);
549 	}
550 	error = g_io_getattr("GEOM::ident", cp, &identsize, ident);
551 	g_access(cp, -1, 0, 0);
552 	if (error != 0) {
553 		G_MOUNTVER_DEBUG(0, "Cannot get disk ident for %s; "
554 		    "not attaching; error = %d.", gp->name, error);
555 		return (1);
556 	}
557 	if (strcmp(ident, sc->sc_ident) != 0) {
558 		G_MOUNTVER_DEBUG(1, "Disk ident for %s (\"%s\") is different "
559 		    "from expected \"%s\", not attaching.", gp->name, ident,
560 		    sc->sc_ident);
561 		return (1);
562 	}
563 
564 	return (0);
565 }
566 
567 static struct g_geom *
568 g_mountver_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
569 {
570 	struct g_mountver_softc *sc;
571 	struct g_consumer *cp;
572 	struct g_geom *gp;
573 	int error;
574 
575 	g_topology_assert();
576 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
577 	G_MOUNTVER_DEBUG(2, "Tasting %s.", pp->name);
578 
579 	/*
580 	 * Let's check if device already exists.
581 	 */
582 	LIST_FOREACH(gp, &mp->geom, geom) {
583 		sc = gp->softc;
584 		if (sc == NULL)
585 			continue;
586 
587 		/* Already attached? */
588 		if (pp == LIST_FIRST(&gp->provider))
589 			return (NULL);
590 
591 		if (sc->sc_orphaned && strcmp(pp->name, sc->sc_provider_name) == 0)
592 			break;
593 	}
594 	if (gp == NULL)
595 		return (NULL);
596 
597 	cp = LIST_FIRST(&gp->consumer);
598 	g_attach(cp, pp);
599 	error = g_mountver_ident_matches(gp);
600 	if (error != 0) {
601 		g_detach(cp);
602 		return (NULL);
603 	}
604 	if (sc->sc_access_r > 0 || sc->sc_access_w > 0 || sc->sc_access_e > 0) {
605 		error = g_access(cp, sc->sc_access_r, sc->sc_access_w, sc->sc_access_e);
606 		if (error != 0) {
607 			G_MOUNTVER_DEBUG(0, "Cannot access %s; error = %d.", pp->name, error);
608 			g_detach(cp);
609 			return (NULL);
610 		}
611 	}
612 	sc->sc_orphaned = 0;
613 	g_mountver_send_queued(gp);
614 	G_MOUNTVER_DEBUG(0, "%s has completed mount verification.", sc->sc_provider_name);
615 
616 	return (gp);
617 }
618 
619 static void
620 g_mountver_config(struct gctl_req *req, struct g_class *mp, const char *verb)
621 {
622 	uint32_t *version;
623 
624 	g_topology_assert();
625 
626 	version = gctl_get_paraml(req, "version", sizeof(*version));
627 	if (version == NULL) {
628 		gctl_error(req, "No '%s' argument.", "version");
629 		return;
630 	}
631 	if (*version != G_MOUNTVER_VERSION) {
632 		gctl_error(req, "Userland and kernel parts are out of sync.");
633 		return;
634 	}
635 
636 	if (strcmp(verb, "create") == 0) {
637 		g_mountver_ctl_create(req, mp);
638 		return;
639 	} else if (strcmp(verb, "destroy") == 0) {
640 		g_mountver_ctl_destroy(req, mp);
641 		return;
642 	}
643 
644 	gctl_error(req, "Unknown verb.");
645 }
646 
647 static void
648 g_mountver_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
649     struct g_consumer *cp, struct g_provider *pp)
650 {
651 	struct g_mountver_softc *sc;
652 
653 	if (pp != NULL || cp != NULL)
654 		return;
655 
656 	sc = gp->softc;
657 	sbuf_printf(sb, "%s<State>%s</State>\n", indent,
658 	    sc->sc_orphaned ? "OFFLINE" : "ONLINE");
659 	sbuf_printf(sb, "%s<Provider-Name>%s</Provider-Name>\n", indent, sc->sc_provider_name);
660 	sbuf_printf(sb, "%s<Disk-Ident>%s</Disk-Ident>\n", indent, sc->sc_ident);
661 }
662 
663 static void
664 g_mountver_shutdown_pre_sync(void *arg, int howto)
665 {
666 	struct g_mountver_softc *sc;
667 	struct g_class *mp;
668 	struct g_geom *gp, *gp2;
669 
670 	mp = arg;
671 	g_topology_lock();
672 	LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
673 		if (gp->softc == NULL)
674 			continue;
675 		sc = gp->softc;
676 		sc->sc_shutting_down = 1;
677 		if (sc->sc_orphaned)
678 			g_mountver_destroy(gp, 1);
679 	}
680 	g_topology_unlock();
681 }
682 
683 static void
684 g_mountver_init(struct g_class *mp)
685 {
686 
687 	g_mountver_pre_sync = EVENTHANDLER_REGISTER(shutdown_pre_sync,
688 	    g_mountver_shutdown_pre_sync, mp, SHUTDOWN_PRI_FIRST);
689 	if (g_mountver_pre_sync == NULL)
690 		G_MOUNTVER_DEBUG(0, "Warning! Cannot register shutdown event.");
691 }
692 
693 static void
694 g_mountver_fini(struct g_class *mp)
695 {
696 
697 	if (g_mountver_pre_sync != NULL)
698 		EVENTHANDLER_DEREGISTER(shutdown_pre_sync, g_mountver_pre_sync);
699 }
700 
701 DECLARE_GEOM_CLASS(g_mountver_class, g_mountver);
702 MODULE_VERSION(geom_mountver, 0);
703