xref: /freebsd/sys/geom/geom_dev.c (revision 5bf5ca772c6de2d53344a78cf461447cc322ccea)
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_compat.h"
42 
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/malloc.h>
46 #include <sys/kernel.h>
47 #include <sys/conf.h>
48 #include <sys/ctype.h>
49 #include <sys/bio.h>
50 #include <sys/bus.h>
51 #include <sys/lock.h>
52 #include <sys/mutex.h>
53 #include <sys/proc.h>
54 #include <sys/errno.h>
55 #include <sys/time.h>
56 #include <sys/disk.h>
57 #include <sys/fcntl.h>
58 #include <sys/limits.h>
59 #include <sys/sysctl.h>
60 #include <geom/geom.h>
61 #include <geom/geom_int.h>
62 #include <machine/stdarg.h>
63 
64 struct g_dev_softc {
65 	struct mtx	 sc_mtx;
66 	struct cdev	*sc_dev;
67 	struct cdev	*sc_alias;
68 	int		 sc_open;
69 	int		 sc_active;
70 };
71 
72 static d_open_t		g_dev_open;
73 static d_close_t	g_dev_close;
74 static d_strategy_t	g_dev_strategy;
75 static d_ioctl_t	g_dev_ioctl;
76 
77 static struct cdevsw g_dev_cdevsw = {
78 	.d_version =	D_VERSION,
79 	.d_open =	g_dev_open,
80 	.d_close =	g_dev_close,
81 	.d_read =	physread,
82 	.d_write =	physwrite,
83 	.d_ioctl =	g_dev_ioctl,
84 	.d_strategy =	g_dev_strategy,
85 	.d_name =	"g_dev",
86 	.d_flags =	D_DISK | D_TRACKCLOSE,
87 };
88 
89 static g_init_t g_dev_init;
90 static g_fini_t g_dev_fini;
91 static g_taste_t g_dev_taste;
92 static g_orphan_t g_dev_orphan;
93 static g_attrchanged_t g_dev_attrchanged;
94 
95 static struct g_class g_dev_class	= {
96 	.name = "DEV",
97 	.version = G_VERSION,
98 	.init = g_dev_init,
99 	.fini = g_dev_fini,
100 	.taste = g_dev_taste,
101 	.orphan = g_dev_orphan,
102 	.attrchanged = g_dev_attrchanged
103 };
104 
105 /*
106  * We target 262144 (8 x 32768) sectors by default as this significantly
107  * increases the throughput on commonly used SSD's with a marginal
108  * increase in non-interruptible request latency.
109  */
110 static uint64_t g_dev_del_max_sectors = 262144;
111 SYSCTL_DECL(_kern_geom);
112 SYSCTL_NODE(_kern_geom, OID_AUTO, dev, CTLFLAG_RW, 0, "GEOM_DEV stuff");
113 SYSCTL_QUAD(_kern_geom_dev, OID_AUTO, delete_max_sectors, CTLFLAG_RW,
114     &g_dev_del_max_sectors, 0, "Maximum number of sectors in a single "
115     "delete request sent to the provider. Larger requests are chunked "
116     "so they can be interrupted. (0 = disable chunking)");
117 
118 static char *dumpdev = NULL;
119 static void
120 g_dev_init(struct g_class *mp)
121 {
122 
123 	dumpdev = kern_getenv("dumpdev");
124 }
125 
126 static void
127 g_dev_fini(struct g_class *mp)
128 {
129 
130 	freeenv(dumpdev);
131 	dumpdev = NULL;
132 }
133 
134 static int
135 g_dev_setdumpdev(struct cdev *dev, struct diocskerneldump_arg *kda,
136     struct thread *td)
137 {
138 	struct g_kerneldump kd;
139 	struct g_consumer *cp;
140 	int error, len;
141 
142 	if (dev == NULL || kda == NULL)
143 		return (set_dumper(NULL, NULL, td, 0, 0, NULL, 0, NULL));
144 
145 	cp = dev->si_drv2;
146 	len = sizeof(kd);
147 	kd.offset = 0;
148 	kd.length = OFF_MAX;
149 	error = g_io_getattr("GEOM::kerneldump", cp, &len, &kd);
150 	if (error != 0)
151 		return (error);
152 
153 	error = set_dumper(&kd.di, devtoname(dev), td, kda->kda_compression,
154 	    kda->kda_encryption, kda->kda_key, kda->kda_encryptedkeysize,
155 	    kda->kda_encryptedkey);
156 	if (error == 0)
157 		dev->si_flags |= SI_DUMPDEV;
158 
159 	return (error);
160 }
161 
162 static int
163 init_dumpdev(struct cdev *dev)
164 {
165 	struct diocskerneldump_arg kda;
166 	struct g_consumer *cp;
167 	const char *devprefix = "/dev/", *devname;
168 	int error;
169 	size_t len;
170 
171 	bzero(&kda, sizeof(kda));
172 	kda.kda_enable = 1;
173 
174 	if (dumpdev == NULL)
175 		return (0);
176 
177 	len = strlen(devprefix);
178 	devname = devtoname(dev);
179 	if (strcmp(devname, dumpdev) != 0 &&
180 	   (strncmp(dumpdev, devprefix, len) != 0 ||
181 	    strcmp(devname, dumpdev + len) != 0))
182 		return (0);
183 
184 	cp = (struct g_consumer *)dev->si_drv2;
185 	error = g_access(cp, 1, 0, 0);
186 	if (error != 0)
187 		return (error);
188 
189 	error = g_dev_setdumpdev(dev, &kda, curthread);
190 	if (error == 0) {
191 		freeenv(dumpdev);
192 		dumpdev = NULL;
193 	}
194 
195 	(void)g_access(cp, -1, 0, 0);
196 
197 	return (error);
198 }
199 
200 static void
201 g_dev_destroy(void *arg, int flags __unused)
202 {
203 	struct g_consumer *cp;
204 	struct g_geom *gp;
205 	struct g_dev_softc *sc;
206 	char buf[SPECNAMELEN + 6];
207 
208 	g_topology_assert();
209 	cp = arg;
210 	gp = cp->geom;
211 	sc = cp->private;
212 	g_trace(G_T_TOPOLOGY, "g_dev_destroy(%p(%s))", cp, gp->name);
213 	snprintf(buf, sizeof(buf), "cdev=%s", gp->name);
214 	devctl_notify_f("GEOM", "DEV", "DESTROY", buf, M_WAITOK);
215 	if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
216 		g_access(cp, -cp->acr, -cp->acw, -cp->ace);
217 	g_detach(cp);
218 	g_destroy_consumer(cp);
219 	g_destroy_geom(gp);
220 	mtx_destroy(&sc->sc_mtx);
221 	g_free(sc);
222 }
223 
224 void
225 g_dev_print(void)
226 {
227 	struct g_geom *gp;
228 	char const *p = "";
229 
230 	LIST_FOREACH(gp, &g_dev_class.geom, geom) {
231 		printf("%s%s", p, gp->name);
232 		p = " ";
233 	}
234 	printf("\n");
235 }
236 
237 static void
238 g_dev_set_physpath(struct g_consumer *cp)
239 {
240 	struct g_dev_softc *sc;
241 	char *physpath;
242 	int error, physpath_len;
243 
244 	if (g_access(cp, 1, 0, 0) != 0)
245 		return;
246 
247 	sc = cp->private;
248 	physpath_len = MAXPATHLEN;
249 	physpath = g_malloc(physpath_len, M_WAITOK|M_ZERO);
250 	error = g_io_getattr("GEOM::physpath", cp, &physpath_len, physpath);
251 	g_access(cp, -1, 0, 0);
252 	if (error == 0 && strlen(physpath) != 0) {
253 		struct cdev *dev, *old_alias_dev;
254 		struct cdev **alias_devp;
255 
256 		dev = sc->sc_dev;
257 		old_alias_dev = sc->sc_alias;
258 		alias_devp = (struct cdev **)&sc->sc_alias;
259 		make_dev_physpath_alias(MAKEDEV_WAITOK, alias_devp, dev,
260 		    old_alias_dev, physpath);
261 	} else if (sc->sc_alias) {
262 		destroy_dev((struct cdev *)sc->sc_alias);
263 		sc->sc_alias = NULL;
264 	}
265 	g_free(physpath);
266 }
267 
268 static void
269 g_dev_set_media(struct g_consumer *cp)
270 {
271 	struct g_dev_softc *sc;
272 	struct cdev *dev;
273 	char buf[SPECNAMELEN + 6];
274 
275 	sc = cp->private;
276 	dev = sc->sc_dev;
277 	snprintf(buf, sizeof(buf), "cdev=%s", dev->si_name);
278 	devctl_notify_f("DEVFS", "CDEV", "MEDIACHANGE", buf, M_WAITOK);
279 	devctl_notify_f("GEOM", "DEV", "MEDIACHANGE", buf, M_WAITOK);
280 	dev = sc->sc_alias;
281 	if (dev != NULL) {
282 		snprintf(buf, sizeof(buf), "cdev=%s", dev->si_name);
283 		devctl_notify_f("DEVFS", "CDEV", "MEDIACHANGE", buf, M_WAITOK);
284 		devctl_notify_f("GEOM", "DEV", "MEDIACHANGE", buf, M_WAITOK);
285 	}
286 }
287 
288 static void
289 g_dev_attrchanged(struct g_consumer *cp, const char *attr)
290 {
291 
292 	if (strcmp(attr, "GEOM::media") == 0) {
293 		g_dev_set_media(cp);
294 		return;
295 	}
296 
297 	if (strcmp(attr, "GEOM::physpath") == 0) {
298 		g_dev_set_physpath(cp);
299 		return;
300 	}
301 }
302 
303 struct g_provider *
304 g_dev_getprovider(struct cdev *dev)
305 {
306 	struct g_consumer *cp;
307 
308 	g_topology_assert();
309 	if (dev == NULL)
310 		return (NULL);
311 	if (dev->si_devsw != &g_dev_cdevsw)
312 		return (NULL);
313 	cp = dev->si_drv2;
314 	return (cp->provider);
315 }
316 
317 static struct g_geom *
318 g_dev_taste(struct g_class *mp, struct g_provider *pp, int insist __unused)
319 {
320 	struct g_geom *gp;
321 	struct g_geom_alias *gap;
322 	struct g_consumer *cp;
323 	struct g_dev_softc *sc;
324 	int error;
325 	struct cdev *dev, *adev;
326 	char buf[SPECNAMELEN + 6];
327 
328 	g_trace(G_T_TOPOLOGY, "dev_taste(%s,%s)", mp->name, pp->name);
329 	g_topology_assert();
330 	gp = g_new_geomf(mp, "%s", pp->name);
331 	sc = g_malloc(sizeof(*sc), M_WAITOK | M_ZERO);
332 	mtx_init(&sc->sc_mtx, "g_dev", NULL, MTX_DEF);
333 	cp = g_new_consumer(gp);
334 	cp->private = sc;
335 	cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE;
336 	error = g_attach(cp, pp);
337 	KASSERT(error == 0,
338 	    ("g_dev_taste(%s) failed to g_attach, err=%d", pp->name, error));
339 	error = make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK, &dev,
340 	    &g_dev_cdevsw, NULL, UID_ROOT, GID_OPERATOR, 0640, "%s", gp->name);
341 	if (error != 0) {
342 		printf("%s: make_dev_p() failed (gp->name=%s, error=%d)\n",
343 		    __func__, gp->name, error);
344 		g_detach(cp);
345 		g_destroy_consumer(cp);
346 		g_destroy_geom(gp);
347 		mtx_destroy(&sc->sc_mtx);
348 		g_free(sc);
349 		return (NULL);
350 	}
351 	dev->si_flags |= SI_UNMAPPED;
352 	sc->sc_dev = dev;
353 
354 	dev->si_iosize_max = MAXPHYS;
355 	dev->si_drv2 = cp;
356 	error = init_dumpdev(dev);
357 	if (error != 0)
358 		printf("%s: init_dumpdev() failed (gp->name=%s, error=%d)\n",
359 		    __func__, gp->name, error);
360 
361 	g_dev_attrchanged(cp, "GEOM::physpath");
362 	snprintf(buf, sizeof(buf), "cdev=%s", gp->name);
363 	devctl_notify_f("GEOM", "DEV", "CREATE", buf, M_WAITOK);
364 	/*
365 	 * Now add all the aliases for this drive
366 	 */
367 	LIST_FOREACH(gap, &pp->geom->aliases, ga_next) {
368 		error = make_dev_alias_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK, &adev, dev,
369 		    "%s", gap->ga_alias);
370 		if (error) {
371 			printf("%s: make_dev_alias_p() failed (name=%s, error=%d)\n",
372 			    __func__, gap->ga_alias, error);
373 			continue;
374 		}
375 		snprintf(buf, sizeof(buf), "cdev=%s", gap->ga_alias);
376 		devctl_notify_f("GEOM", "DEV", "CREATE", buf, M_WAITOK);
377 	}
378 
379 	return (gp);
380 }
381 
382 static int
383 g_dev_open(struct cdev *dev, int flags, int fmt, struct thread *td)
384 {
385 	struct g_consumer *cp;
386 	struct g_dev_softc *sc;
387 	int error, r, w, e;
388 
389 	cp = dev->si_drv2;
390 	if (cp == NULL)
391 		return (ENXIO);		/* g_dev_taste() not done yet */
392 	g_trace(G_T_ACCESS, "g_dev_open(%s, %d, %d, %p)",
393 	    cp->geom->name, flags, fmt, td);
394 
395 	r = flags & FREAD ? 1 : 0;
396 	w = flags & FWRITE ? 1 : 0;
397 #ifdef notyet
398 	e = flags & O_EXCL ? 1 : 0;
399 #else
400 	e = 0;
401 #endif
402 
403 	/*
404 	 * This happens on attempt to open a device node with O_EXEC.
405 	 */
406 	if (r + w + e == 0)
407 		return (EINVAL);
408 
409 	if (w) {
410 		/*
411 		 * When running in very secure mode, do not allow
412 		 * opens for writing of any disks.
413 		 */
414 		error = securelevel_ge(td->td_ucred, 2);
415 		if (error)
416 			return (error);
417 	}
418 	g_topology_lock();
419 	error = g_access(cp, r, w, e);
420 	g_topology_unlock();
421 	if (error == 0) {
422 		sc = cp->private;
423 		mtx_lock(&sc->sc_mtx);
424 		if (sc->sc_open == 0 && sc->sc_active != 0)
425 			wakeup(&sc->sc_active);
426 		sc->sc_open += r + w + e;
427 		mtx_unlock(&sc->sc_mtx);
428 	}
429 	return (error);
430 }
431 
432 static int
433 g_dev_close(struct cdev *dev, int flags, int fmt, struct thread *td)
434 {
435 	struct g_consumer *cp;
436 	struct g_dev_softc *sc;
437 	int error, r, w, e;
438 
439 	cp = dev->si_drv2;
440 	if (cp == NULL)
441 		return (ENXIO);
442 	g_trace(G_T_ACCESS, "g_dev_close(%s, %d, %d, %p)",
443 	    cp->geom->name, flags, fmt, td);
444 
445 	r = flags & FREAD ? -1 : 0;
446 	w = flags & FWRITE ? -1 : 0;
447 #ifdef notyet
448 	e = flags & O_EXCL ? -1 : 0;
449 #else
450 	e = 0;
451 #endif
452 
453 	/*
454 	 * The vgonel(9) - caused by eg. forced unmount of devfs - calls
455 	 * VOP_CLOSE(9) on devfs vnode without any FREAD or FWRITE flags,
456 	 * which would result in zero deltas, which in turn would cause
457 	 * panic in g_access(9).
458 	 *
459 	 * Note that we cannot zero the counters (ie. do "r = cp->acr"
460 	 * etc) instead, because the consumer might be opened in another
461 	 * devfs instance.
462 	 */
463 	if (r + w + e == 0)
464 		return (EINVAL);
465 
466 	sc = cp->private;
467 	mtx_lock(&sc->sc_mtx);
468 	sc->sc_open += r + w + e;
469 	while (sc->sc_open == 0 && sc->sc_active != 0)
470 		msleep(&sc->sc_active, &sc->sc_mtx, 0, "PRIBIO", 0);
471 	mtx_unlock(&sc->sc_mtx);
472 	g_topology_lock();
473 	error = g_access(cp, r, w, e);
474 	g_topology_unlock();
475 	return (error);
476 }
477 
478 /*
479  * XXX: Until we have unmessed the ioctl situation, there is a race against
480  * XXX: a concurrent orphanization.  We cannot close it by holding topology
481  * XXX: since that would prevent us from doing our job, and stalling events
482  * XXX: will break (actually: stall) the BSD disklabel hacks.
483  */
484 static int
485 g_dev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
486 {
487 	struct g_consumer *cp;
488 	struct g_provider *pp;
489 	off_t offset, length, chunk, odd;
490 	int i, error;
491 
492 	cp = dev->si_drv2;
493 	pp = cp->provider;
494 
495 	error = 0;
496 	KASSERT(cp->acr || cp->acw,
497 	    ("Consumer with zero access count in g_dev_ioctl"));
498 
499 	i = IOCPARM_LEN(cmd);
500 	switch (cmd) {
501 	case DIOCGSECTORSIZE:
502 		*(u_int *)data = cp->provider->sectorsize;
503 		if (*(u_int *)data == 0)
504 			error = ENOENT;
505 		break;
506 	case DIOCGMEDIASIZE:
507 		*(off_t *)data = cp->provider->mediasize;
508 		if (*(off_t *)data == 0)
509 			error = ENOENT;
510 		break;
511 	case DIOCGFWSECTORS:
512 		error = g_io_getattr("GEOM::fwsectors", cp, &i, data);
513 		if (error == 0 && *(u_int *)data == 0)
514 			error = ENOENT;
515 		break;
516 	case DIOCGFWHEADS:
517 		error = g_io_getattr("GEOM::fwheads", cp, &i, data);
518 		if (error == 0 && *(u_int *)data == 0)
519 			error = ENOENT;
520 		break;
521 	case DIOCGFRONTSTUFF:
522 		error = g_io_getattr("GEOM::frontstuff", cp, &i, data);
523 		break;
524 #ifdef COMPAT_FREEBSD11
525 	case DIOCSKERNELDUMP_FREEBSD11:
526 	    {
527 		struct diocskerneldump_arg kda;
528 
529 		bzero(&kda, sizeof(kda));
530 		kda.kda_encryption = KERNELDUMP_ENC_NONE;
531 		kda.kda_enable = (uint8_t)*(u_int *)data;
532 		if (kda.kda_enable == 0)
533 			error = g_dev_setdumpdev(NULL, NULL, td);
534 		else
535 			error = g_dev_setdumpdev(dev, &kda, td);
536 		break;
537 	    }
538 #endif
539 	case DIOCSKERNELDUMP:
540 	    {
541 		struct diocskerneldump_arg *kda;
542 		uint8_t *encryptedkey;
543 
544 		kda = (struct diocskerneldump_arg *)data;
545 		if (kda->kda_enable == 0) {
546 			error = g_dev_setdumpdev(NULL, NULL, td);
547 			break;
548 		}
549 
550 		if (kda->kda_encryption != KERNELDUMP_ENC_NONE) {
551 			if (kda->kda_encryptedkeysize <= 0 ||
552 			    kda->kda_encryptedkeysize >
553 			    KERNELDUMP_ENCKEY_MAX_SIZE) {
554 				return (EINVAL);
555 			}
556 			encryptedkey = malloc(kda->kda_encryptedkeysize, M_TEMP,
557 			    M_WAITOK);
558 			error = copyin(kda->kda_encryptedkey, encryptedkey,
559 			    kda->kda_encryptedkeysize);
560 		} else {
561 			encryptedkey = NULL;
562 		}
563 		if (error == 0) {
564 			kda->kda_encryptedkey = encryptedkey;
565 			error = g_dev_setdumpdev(dev, kda, td);
566 		}
567 		if (encryptedkey != NULL) {
568 			explicit_bzero(encryptedkey, kda->kda_encryptedkeysize);
569 			free(encryptedkey, M_TEMP);
570 		}
571 		explicit_bzero(kda, sizeof(*kda));
572 		break;
573 	    }
574 	case DIOCGFLUSH:
575 		error = g_io_flush(cp);
576 		break;
577 	case DIOCGDELETE:
578 		offset = ((off_t *)data)[0];
579 		length = ((off_t *)data)[1];
580 		if ((offset % cp->provider->sectorsize) != 0 ||
581 		    (length % cp->provider->sectorsize) != 0 || length <= 0) {
582 			printf("%s: offset=%jd length=%jd\n", __func__, offset,
583 			    length);
584 			error = EINVAL;
585 			break;
586 		}
587 		while (length > 0) {
588 			chunk = length;
589 			if (g_dev_del_max_sectors != 0 && chunk >
590 			    g_dev_del_max_sectors * cp->provider->sectorsize) {
591 				chunk = g_dev_del_max_sectors *
592 				    cp->provider->sectorsize;
593 				if (cp->provider->stripesize > 0) {
594 					odd = (offset + chunk +
595 					    cp->provider->stripeoffset) %
596 					    cp->provider->stripesize;
597 					if (chunk > odd)
598 						chunk -= odd;
599 				}
600 			}
601 			error = g_delete_data(cp, offset, chunk);
602 			length -= chunk;
603 			offset += chunk;
604 			if (error)
605 				break;
606 			/*
607 			 * Since the request size can be large, the service
608 			 * time can be is likewise.  We make this ioctl
609 			 * interruptible by checking for signals for each bio.
610 			 */
611 			if (SIGPENDING(td))
612 				break;
613 		}
614 		break;
615 	case DIOCGIDENT:
616 		error = g_io_getattr("GEOM::ident", cp, &i, data);
617 		break;
618 	case DIOCGPROVIDERNAME:
619 		if (pp == NULL)
620 			return (ENOENT);
621 		strlcpy(data, pp->name, i);
622 		break;
623 	case DIOCGSTRIPESIZE:
624 		*(off_t *)data = cp->provider->stripesize;
625 		break;
626 	case DIOCGSTRIPEOFFSET:
627 		*(off_t *)data = cp->provider->stripeoffset;
628 		break;
629 	case DIOCGPHYSPATH:
630 		error = g_io_getattr("GEOM::physpath", cp, &i, data);
631 		if (error == 0 && *(char *)data == '\0')
632 			error = ENOENT;
633 		break;
634 	case DIOCGATTR: {
635 		struct diocgattr_arg *arg = (struct diocgattr_arg *)data;
636 
637 		if (arg->len > sizeof(arg->value)) {
638 			error = EINVAL;
639 			break;
640 		}
641 		error = g_io_getattr(arg->name, cp, &arg->len, &arg->value);
642 		break;
643 	}
644 	case DIOCZONECMD: {
645 		struct disk_zone_args *zone_args =(struct disk_zone_args *)data;
646 		struct disk_zone_rep_entry *new_entries, *old_entries;
647 		struct disk_zone_report *rep;
648 		size_t alloc_size;
649 
650 		old_entries = NULL;
651 		new_entries = NULL;
652 		rep = NULL;
653 		alloc_size = 0;
654 
655 		if (zone_args->zone_cmd == DISK_ZONE_REPORT_ZONES) {
656 
657 			rep = &zone_args->zone_params.report;
658 			alloc_size = rep->entries_allocated *
659 			    sizeof(struct disk_zone_rep_entry);
660 			if (alloc_size != 0)
661 				new_entries = g_malloc(alloc_size,
662 				    M_WAITOK| M_ZERO);
663 			old_entries = rep->entries;
664 			rep->entries = new_entries;
665 		}
666 		error = g_io_zonecmd(zone_args, cp);
667 		if ((zone_args->zone_cmd == DISK_ZONE_REPORT_ZONES)
668 		 && (alloc_size != 0)
669 		 && (error == 0)) {
670 			error = copyout(new_entries, old_entries, alloc_size);
671 		}
672 		if ((old_entries != NULL)
673 		 && (rep != NULL))
674 			rep->entries = old_entries;
675 
676 		if (new_entries != NULL)
677 			g_free(new_entries);
678 		break;
679 	}
680 	default:
681 		if (cp->provider->geom->ioctl != NULL) {
682 			error = cp->provider->geom->ioctl(cp->provider, cmd, data, fflag, td);
683 		} else {
684 			error = ENOIOCTL;
685 		}
686 	}
687 
688 	return (error);
689 }
690 
691 static void
692 g_dev_done(struct bio *bp2)
693 {
694 	struct g_consumer *cp;
695 	struct g_dev_softc *sc;
696 	struct bio *bp;
697 	int destroy;
698 
699 	cp = bp2->bio_from;
700 	sc = cp->private;
701 	bp = bp2->bio_parent;
702 	bp->bio_error = bp2->bio_error;
703 	bp->bio_completed = bp2->bio_completed;
704 	bp->bio_resid = bp->bio_length - bp2->bio_completed;
705 	if (bp2->bio_cmd == BIO_ZONE)
706 		bcopy(&bp2->bio_zone, &bp->bio_zone, sizeof(bp->bio_zone));
707 
708 	if (bp2->bio_error != 0) {
709 		g_trace(G_T_BIO, "g_dev_done(%p) had error %d",
710 		    bp2, bp2->bio_error);
711 		bp->bio_flags |= BIO_ERROR;
712 	} else {
713 		g_trace(G_T_BIO, "g_dev_done(%p/%p) resid %ld completed %jd",
714 		    bp2, bp, bp2->bio_resid, (intmax_t)bp2->bio_completed);
715 	}
716 	g_destroy_bio(bp2);
717 	destroy = 0;
718 	mtx_lock(&sc->sc_mtx);
719 	if ((--sc->sc_active) == 0) {
720 		if (sc->sc_open == 0)
721 			wakeup(&sc->sc_active);
722 		if (sc->sc_dev == NULL)
723 			destroy = 1;
724 	}
725 	mtx_unlock(&sc->sc_mtx);
726 	if (destroy)
727 		g_post_event(g_dev_destroy, cp, M_NOWAIT, NULL);
728 	biodone(bp);
729 }
730 
731 static void
732 g_dev_strategy(struct bio *bp)
733 {
734 	struct g_consumer *cp;
735 	struct bio *bp2;
736 	struct cdev *dev;
737 	struct g_dev_softc *sc;
738 
739 	KASSERT(bp->bio_cmd == BIO_READ ||
740 	        bp->bio_cmd == BIO_WRITE ||
741 	        bp->bio_cmd == BIO_DELETE ||
742 		bp->bio_cmd == BIO_FLUSH ||
743 		bp->bio_cmd == BIO_ZONE,
744 		("Wrong bio_cmd bio=%p cmd=%d", bp, bp->bio_cmd));
745 	dev = bp->bio_dev;
746 	cp = dev->si_drv2;
747 	sc = cp->private;
748 	KASSERT(cp->acr || cp->acw,
749 	    ("Consumer with zero access count in g_dev_strategy"));
750 	biotrack(bp, __func__);
751 #ifdef INVARIANTS
752 	if ((bp->bio_offset % cp->provider->sectorsize) != 0 ||
753 	    (bp->bio_bcount % cp->provider->sectorsize) != 0) {
754 		bp->bio_resid = bp->bio_bcount;
755 		biofinish(bp, NULL, EINVAL);
756 		return;
757 	}
758 #endif
759 	mtx_lock(&sc->sc_mtx);
760 	KASSERT(sc->sc_open > 0, ("Closed device in g_dev_strategy"));
761 	sc->sc_active++;
762 	mtx_unlock(&sc->sc_mtx);
763 
764 	for (;;) {
765 		/*
766 		 * XXX: This is not an ideal solution, but I believe it to
767 		 * XXX: deadlock safely, all things considered.
768 		 */
769 		bp2 = g_clone_bio(bp);
770 		if (bp2 != NULL)
771 			break;
772 		pause("gdstrat", hz / 10);
773 	}
774 	KASSERT(bp2 != NULL, ("XXX: ENOMEM in a bad place"));
775 	bp2->bio_done = g_dev_done;
776 	g_trace(G_T_BIO,
777 	    "g_dev_strategy(%p/%p) offset %jd length %jd data %p cmd %d",
778 	    bp, bp2, (intmax_t)bp->bio_offset, (intmax_t)bp2->bio_length,
779 	    bp2->bio_data, bp2->bio_cmd);
780 	g_io_request(bp2, cp);
781 	KASSERT(cp->acr || cp->acw,
782 	    ("g_dev_strategy raced with g_dev_close and lost"));
783 
784 }
785 
786 /*
787  * g_dev_callback()
788  *
789  * Called by devfs when asynchronous device destruction is completed.
790  * - Mark that we have no attached device any more.
791  * - If there are no outstanding requests, schedule geom destruction.
792  *   Otherwise destruction will be scheduled later by g_dev_done().
793  */
794 
795 static void
796 g_dev_callback(void *arg)
797 {
798 	struct g_consumer *cp;
799 	struct g_dev_softc *sc;
800 	int destroy;
801 
802 	cp = arg;
803 	sc = cp->private;
804 	g_trace(G_T_TOPOLOGY, "g_dev_callback(%p(%s))", cp, cp->geom->name);
805 
806 	mtx_lock(&sc->sc_mtx);
807 	sc->sc_dev = NULL;
808 	sc->sc_alias = NULL;
809 	destroy = (sc->sc_active == 0);
810 	mtx_unlock(&sc->sc_mtx);
811 	if (destroy)
812 		g_post_event(g_dev_destroy, cp, M_WAITOK, NULL);
813 }
814 
815 /*
816  * g_dev_orphan()
817  *
818  * Called from below when the provider orphaned us.
819  * - Clear any dump settings.
820  * - Request asynchronous device destruction to prevent any more requests
821  *   from coming in.  The provider is already marked with an error, so
822  *   anything which comes in the interim will be returned immediately.
823  */
824 
825 static void
826 g_dev_orphan(struct g_consumer *cp)
827 {
828 	struct cdev *dev;
829 	struct g_dev_softc *sc;
830 
831 	g_topology_assert();
832 	sc = cp->private;
833 	dev = sc->sc_dev;
834 	g_trace(G_T_TOPOLOGY, "g_dev_orphan(%p(%s))", cp, cp->geom->name);
835 
836 	/* Reset any dump-area set on this device */
837 	if (dev->si_flags & SI_DUMPDEV)
838 		(void)set_dumper(NULL, NULL, curthread, 0, 0, NULL, 0, NULL);
839 
840 	/* Destroy the struct cdev *so we get no more requests */
841 	destroy_dev_sched_cb(dev, g_dev_callback, cp);
842 }
843 
844 DECLARE_GEOM_CLASS(g_dev_class, g_dev);
845