xref: /freebsd/sys/geom/geom_dev.c (revision 7899f917b1c0ea178f1d2be0cfb452086d079d23)
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/param.h>
39 #include <sys/systm.h>
40 #include <sys/malloc.h>
41 #include <sys/kernel.h>
42 #include <sys/conf.h>
43 #include <sys/ctype.h>
44 #include <sys/bio.h>
45 #include <sys/devctl.h>
46 #include <sys/lock.h>
47 #include <sys/mutex.h>
48 #include <sys/proc.h>
49 #include <sys/errno.h>
50 #include <sys/time.h>
51 #include <sys/disk.h>
52 #include <sys/fcntl.h>
53 #include <sys/limits.h>
54 #include <sys/selinfo.h>
55 #include <sys/sysctl.h>
56 #include <geom/geom.h>
57 #include <geom/geom_int.h>
58 #include <machine/stdarg.h>
59 
60 struct g_dev_softc {
61 	struct mtx	 sc_mtx;
62 	struct cdev	*sc_dev;
63 	struct cdev	*sc_alias;
64 	int		 sc_open;
65 	u_int		 sc_active;
66 	struct selinfo	 sc_selinfo;
67 #define	SC_A_DESTROY	(1 << 31)
68 #define	SC_A_OPEN	(1 << 30)
69 #define	SC_A_ACTIVE	(SC_A_OPEN - 1)
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 static d_kqfilter_t	g_dev_kqfilter;
77 
78 static void		gdev_filter_detach(struct knote *kn);
79 static int		gdev_filter_vnode(struct knote *kn, long hint);
80 
81 static struct filterops gdev_filterops_vnode = {
82 	.f_isfd = 1,
83 	.f_detach = gdev_filter_detach,
84 	.f_event = gdev_filter_vnode,
85 };
86 
87 static struct cdevsw g_dev_cdevsw = {
88 	.d_version =	D_VERSION,
89 	.d_open =	g_dev_open,
90 	.d_close =	g_dev_close,
91 	.d_read =	physread,
92 	.d_write =	physwrite,
93 	.d_ioctl =	g_dev_ioctl,
94 	.d_strategy =	g_dev_strategy,
95 	.d_name =	"g_dev",
96 	.d_flags =	D_DISK | D_TRACKCLOSE,
97 	.d_kqfilter =	g_dev_kqfilter,
98 };
99 
100 static g_init_t g_dev_init;
101 static g_fini_t g_dev_fini;
102 static g_taste_t g_dev_taste;
103 static g_orphan_t g_dev_orphan;
104 static g_attrchanged_t g_dev_attrchanged;
105 static g_resize_t g_dev_resize;
106 
107 static struct g_class g_dev_class	= {
108 	.name = "DEV",
109 	.version = G_VERSION,
110 	.init = g_dev_init,
111 	.fini = g_dev_fini,
112 	.taste = g_dev_taste,
113 	.orphan = g_dev_orphan,
114 	.attrchanged = g_dev_attrchanged,
115 	.resize = g_dev_resize
116 };
117 
118 /*
119  * We target 262144 (8 x 32768) sectors by default as this significantly
120  * increases the throughput on commonly used SSD's with a marginal
121  * increase in non-interruptible request latency.
122  */
123 static uint64_t g_dev_del_max_sectors = 262144;
124 SYSCTL_DECL(_kern_geom);
125 SYSCTL_NODE(_kern_geom, OID_AUTO, dev, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
126     "GEOM_DEV stuff");
127 SYSCTL_QUAD(_kern_geom_dev, OID_AUTO, delete_max_sectors, CTLFLAG_RW,
128     &g_dev_del_max_sectors, 0, "Maximum number of sectors in a single "
129     "delete request sent to the provider. Larger requests are chunked "
130     "so they can be interrupted. (0 = disable chunking)");
131 
132 static char *dumpdev = NULL;
133 static void
134 g_dev_init(struct g_class *mp)
135 {
136 
137 	dumpdev = kern_getenv("dumpdev");
138 }
139 
140 static void
141 g_dev_fini(struct g_class *mp)
142 {
143 
144 	freeenv(dumpdev);
145 	dumpdev = NULL;
146 }
147 
148 static int
149 g_dev_setdumpdev(struct cdev *dev, struct diocskerneldump_arg *kda)
150 {
151 	struct g_kerneldump kd;
152 	struct g_consumer *cp;
153 	int error, len;
154 
155 	MPASS(dev != NULL && kda != NULL);
156 	MPASS(kda->kda_index != KDA_REMOVE);
157 
158 	cp = dev->si_drv2;
159 	len = sizeof(kd);
160 	memset(&kd, 0, len);
161 	kd.offset = 0;
162 	kd.length = OFF_MAX;
163 	error = g_io_getattr("GEOM::kerneldump", cp, &len, &kd);
164 	if (error != 0)
165 		return (error);
166 
167 	error = dumper_insert(&kd.di, devtoname(dev), kda);
168 	if (error == 0)
169 		dev->si_flags |= SI_DUMPDEV;
170 
171 	return (error);
172 }
173 
174 static int
175 init_dumpdev(struct cdev *dev)
176 {
177 	struct diocskerneldump_arg kda;
178 	struct g_consumer *cp;
179 	const char *devprefix = _PATH_DEV, *devname;
180 	int error;
181 	size_t len;
182 
183 	bzero(&kda, sizeof(kda));
184 	kda.kda_index = KDA_APPEND;
185 
186 	if (dumpdev == NULL)
187 		return (0);
188 
189 	len = strlen(devprefix);
190 	devname = devtoname(dev);
191 	if (strcmp(devname, dumpdev) != 0 &&
192 	   (strncmp(dumpdev, devprefix, len) != 0 ||
193 	    strcmp(devname, dumpdev + len) != 0))
194 		return (0);
195 
196 	cp = (struct g_consumer *)dev->si_drv2;
197 	error = g_access(cp, 1, 0, 0);
198 	if (error != 0)
199 		return (error);
200 
201 	error = g_dev_setdumpdev(dev, &kda);
202 	if (error == 0) {
203 		freeenv(dumpdev);
204 		dumpdev = NULL;
205 	}
206 
207 	(void)g_access(cp, -1, 0, 0);
208 
209 	return (error);
210 }
211 
212 static void
213 g_dev_destroy(void *arg, int flags __unused)
214 {
215 	struct g_consumer *cp;
216 	struct g_geom *gp;
217 	struct g_dev_softc *sc;
218 	char buf[SPECNAMELEN + 6];
219 
220 	g_topology_assert();
221 	cp = arg;
222 	gp = cp->geom;
223 	sc = cp->private;
224 	g_trace(G_T_TOPOLOGY, "g_dev_destroy(%p(%s))", cp, gp->name);
225 	snprintf(buf, sizeof(buf), "cdev=%s", gp->name);
226 	devctl_notify("GEOM", "DEV", "DESTROY", buf);
227 	knlist_clear(&sc->sc_selinfo.si_note, 0);
228 	knlist_destroy(&sc->sc_selinfo.si_note);
229 	if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
230 		g_access(cp, -cp->acr, -cp->acw, -cp->ace);
231 	g_detach(cp);
232 	g_destroy_consumer(cp);
233 	g_destroy_geom(gp);
234 	mtx_destroy(&sc->sc_mtx);
235 	g_free(sc);
236 }
237 
238 void
239 g_dev_print(void)
240 {
241 	struct g_geom *gp;
242 	char const *p = "";
243 
244 	LIST_FOREACH(gp, &g_dev_class.geom, geom) {
245 		printf("%s%s", p, gp->name);
246 		p = " ";
247 	}
248 	printf("\n");
249 }
250 
251 static void
252 g_dev_set_physpath(struct g_consumer *cp)
253 {
254 	struct g_dev_softc *sc;
255 	char *physpath;
256 	int error, physpath_len;
257 
258 	if (g_access(cp, 1, 0, 0) != 0)
259 		return;
260 
261 	sc = cp->private;
262 	physpath_len = MAXPATHLEN;
263 	physpath = g_malloc(physpath_len, M_WAITOK|M_ZERO);
264 	error = g_io_getattr("GEOM::physpath", cp, &physpath_len, physpath);
265 	g_access(cp, -1, 0, 0);
266 	if (error == 0 && strlen(physpath) != 0) {
267 		struct cdev *dev, *old_alias_dev;
268 		struct cdev **alias_devp;
269 
270 		dev = sc->sc_dev;
271 		old_alias_dev = sc->sc_alias;
272 		alias_devp = (struct cdev **)&sc->sc_alias;
273 		make_dev_physpath_alias(MAKEDEV_WAITOK | MAKEDEV_CHECKNAME,
274 		    alias_devp, dev, old_alias_dev, physpath);
275 	} else if (sc->sc_alias) {
276 		destroy_dev((struct cdev *)sc->sc_alias);
277 		sc->sc_alias = NULL;
278 	}
279 	g_free(physpath);
280 }
281 
282 static void
283 g_dev_set_media(struct g_consumer *cp)
284 {
285 	struct g_dev_softc *sc;
286 	struct cdev *dev;
287 	char buf[SPECNAMELEN + 6];
288 
289 	sc = cp->private;
290 	dev = sc->sc_dev;
291 	snprintf(buf, sizeof(buf), "cdev=%s", dev->si_name);
292 	devctl_notify("DEVFS", "CDEV", "MEDIACHANGE", buf);
293 	devctl_notify("GEOM", "DEV", "MEDIACHANGE", buf);
294 	dev = sc->sc_alias;
295 	if (dev != NULL) {
296 		snprintf(buf, sizeof(buf), "cdev=%s", dev->si_name);
297 		devctl_notify("DEVFS", "CDEV", "MEDIACHANGE", buf);
298 		devctl_notify("GEOM", "DEV", "MEDIACHANGE", buf);
299 	}
300 }
301 
302 static void
303 g_dev_attrchanged(struct g_consumer *cp, const char *attr)
304 {
305 
306 	if (strcmp(attr, "GEOM::media") == 0) {
307 		g_dev_set_media(cp);
308 		return;
309 	}
310 
311 	if (strcmp(attr, "GEOM::physpath") == 0) {
312 		g_dev_set_physpath(cp);
313 		return;
314 	}
315 }
316 
317 static void
318 g_dev_resize(struct g_consumer *cp)
319 {
320 	struct g_dev_softc *sc;
321 	char buf[SPECNAMELEN + 6];
322 
323 	sc = cp->private;
324 	KNOTE_UNLOCKED(&sc->sc_selinfo.si_note, NOTE_ATTRIB);
325 
326 	snprintf(buf, sizeof(buf), "cdev=%s", cp->provider->name);
327 	devctl_notify("GEOM", "DEV", "SIZECHANGE", buf);
328 }
329 
330 struct g_provider *
331 g_dev_getprovider(struct cdev *dev)
332 {
333 	struct g_consumer *cp;
334 
335 	g_topology_assert();
336 	if (dev == NULL)
337 		return (NULL);
338 	if (dev->si_devsw != &g_dev_cdevsw)
339 		return (NULL);
340 	cp = dev->si_drv2;
341 	return (cp->provider);
342 }
343 
344 static struct g_geom *
345 g_dev_taste(struct g_class *mp, struct g_provider *pp, int insist __unused)
346 {
347 	struct g_geom *gp;
348 	struct g_geom_alias *gap;
349 	struct g_consumer *cp;
350 	struct g_dev_softc *sc;
351 	int error;
352 	struct cdev *dev, *adev;
353 	char buf[SPECNAMELEN + 6];
354 	struct make_dev_args args;
355 
356 	g_trace(G_T_TOPOLOGY, "dev_taste(%s,%s)", mp->name, pp->name);
357 	g_topology_assert();
358 	gp = g_new_geomf(mp, "%s", pp->name);
359 	sc = g_malloc(sizeof(*sc), M_WAITOK | M_ZERO);
360 	mtx_init(&sc->sc_mtx, "g_dev", NULL, MTX_DEF);
361 	cp = g_new_consumer(gp);
362 	cp->private = sc;
363 	cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE;
364 	error = g_attach(cp, pp);
365 	if (error != 0) {
366 		printf("%s: g_dev_taste(%s) failed to g_attach, error=%d\n",
367 		    __func__, pp->name, error);
368 		g_destroy_consumer(cp);
369 		g_destroy_geom(gp);
370 		mtx_destroy(&sc->sc_mtx);
371 		g_free(sc);
372 		return (NULL);
373 	}
374 	make_dev_args_init(&args);
375 	args.mda_flags = MAKEDEV_CHECKNAME | MAKEDEV_WAITOK;
376 	args.mda_devsw = &g_dev_cdevsw;
377 	args.mda_cr = NULL;
378 	args.mda_uid = UID_ROOT;
379 	args.mda_gid = GID_OPERATOR;
380 	args.mda_mode = 0640;
381 	args.mda_si_drv1 = sc;
382 	args.mda_si_drv2 = cp;
383 	error = make_dev_s(&args, &sc->sc_dev, "%s", gp->name);
384 	if (error != 0) {
385 		printf("%s: make_dev_p() failed (gp->name=%s, error=%d)\n",
386 		    __func__, gp->name, error);
387 		g_detach(cp);
388 		g_destroy_consumer(cp);
389 		g_destroy_geom(gp);
390 		mtx_destroy(&sc->sc_mtx);
391 		g_free(sc);
392 		return (NULL);
393 	}
394 	dev = sc->sc_dev;
395 	dev->si_flags |= SI_UNMAPPED;
396 	dev->si_iosize_max = maxphys;
397 	knlist_init_mtx(&sc->sc_selinfo.si_note, &sc->sc_mtx);
398 	error = init_dumpdev(dev);
399 	if (error != 0)
400 		printf("%s: init_dumpdev() failed (gp->name=%s, error=%d)\n",
401 		    __func__, gp->name, error);
402 
403 	g_dev_attrchanged(cp, "GEOM::physpath");
404 	snprintf(buf, sizeof(buf), "cdev=%s", gp->name);
405 	devctl_notify("GEOM", "DEV", "CREATE", buf);
406 	/*
407 	 * Now add all the aliases for this drive
408 	 */
409 	LIST_FOREACH(gap, &pp->aliases, ga_next) {
410 		error = make_dev_alias_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK, &adev, dev,
411 		    "%s", gap->ga_alias);
412 		if (error) {
413 			printf("%s: make_dev_alias_p() failed (name=%s, error=%d)\n",
414 			    __func__, gap->ga_alias, error);
415 			continue;
416 		}
417 		snprintf(buf, sizeof(buf), "cdev=%s", gap->ga_alias);
418 		devctl_notify("GEOM", "DEV", "CREATE", buf);
419 	}
420 
421 	return (gp);
422 }
423 
424 static int
425 g_dev_open(struct cdev *dev, int flags, int fmt, struct thread *td)
426 {
427 	struct g_consumer *cp;
428 	struct g_dev_softc *sc;
429 	int error, r, w, e;
430 
431 	cp = dev->si_drv2;
432 	g_trace(G_T_ACCESS, "g_dev_open(%s, %d, %d, %p)",
433 	    cp->geom->name, flags, fmt, td);
434 
435 	r = flags & FREAD ? 1 : 0;
436 	w = flags & FWRITE ? 1 : 0;
437 #ifdef notyet
438 	e = flags & O_EXCL ? 1 : 0;
439 #else
440 	e = 0;
441 #endif
442 
443 	/*
444 	 * This happens on attempt to open a device node with O_EXEC.
445 	 */
446 	if (r + w + e == 0)
447 		return (EINVAL);
448 
449 	if (w) {
450 		/*
451 		 * When running in very secure mode, do not allow
452 		 * opens for writing of any disks.
453 		 */
454 		error = securelevel_ge(td->td_ucred, 2);
455 		if (error)
456 			return (error);
457 	}
458 	g_topology_lock();
459 	error = g_access(cp, r, w, e);
460 	g_topology_unlock();
461 	if (error == 0) {
462 		sc = dev->si_drv1;
463 		mtx_lock(&sc->sc_mtx);
464 		if (sc->sc_open == 0 && (sc->sc_active & SC_A_ACTIVE) != 0)
465 			wakeup(&sc->sc_active);
466 		sc->sc_open += r + w + e;
467 		if (sc->sc_open == 0)
468 			atomic_clear_int(&sc->sc_active, SC_A_OPEN);
469 		else
470 			atomic_set_int(&sc->sc_active, SC_A_OPEN);
471 		KNOTE_LOCKED(&sc->sc_selinfo.si_note, NOTE_OPEN);
472 		mtx_unlock(&sc->sc_mtx);
473 	}
474 	return (error);
475 }
476 
477 static int
478 g_dev_close(struct cdev *dev, int flags, int fmt, struct thread *td)
479 {
480 	struct g_consumer *cp;
481 	struct g_dev_softc *sc;
482 	int error, r, w, e;
483 
484 	cp = dev->si_drv2;
485 	g_trace(G_T_ACCESS, "g_dev_close(%s, %d, %d, %p)",
486 	    cp->geom->name, flags, fmt, td);
487 
488 	r = flags & FREAD ? -1 : 0;
489 	w = flags & FWRITE ? -1 : 0;
490 #ifdef notyet
491 	e = flags & O_EXCL ? -1 : 0;
492 #else
493 	e = 0;
494 #endif
495 
496 	/*
497 	 * The vgonel(9) - caused by eg. forced unmount of devfs - calls
498 	 * VOP_CLOSE(9) on devfs vnode without any FREAD or FWRITE flags,
499 	 * which would result in zero deltas, which in turn would cause
500 	 * panic in g_access(9).
501 	 *
502 	 * Note that we cannot zero the counters (ie. do "r = cp->acr"
503 	 * etc) instead, because the consumer might be opened in another
504 	 * devfs instance.
505 	 */
506 	if (r + w + e == 0)
507 		return (EINVAL);
508 
509 	sc = dev->si_drv1;
510 	mtx_lock(&sc->sc_mtx);
511 	sc->sc_open += r + w + e;
512 	if (sc->sc_open == 0)
513 		atomic_clear_int(&sc->sc_active, SC_A_OPEN);
514 	else
515 		atomic_set_int(&sc->sc_active, SC_A_OPEN);
516 	while (sc->sc_open == 0 && (sc->sc_active & SC_A_ACTIVE) != 0)
517 		msleep(&sc->sc_active, &sc->sc_mtx, 0, "g_dev_close", hz / 10);
518 	KNOTE_LOCKED(&sc->sc_selinfo.si_note, NOTE_CLOSE | (w ? NOTE_CLOSE_WRITE : 0));
519 	mtx_unlock(&sc->sc_mtx);
520 	g_topology_lock();
521 	error = g_access(cp, r, w, e);
522 	g_topology_unlock();
523 	return (error);
524 }
525 
526 static int
527 g_dev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
528 {
529 	struct g_consumer *cp;
530 	struct g_provider *pp;
531 	off_t offset, length, chunk, odd;
532 	int i, error;
533 
534 	cp = dev->si_drv2;
535 	pp = cp->provider;
536 
537 	/* If consumer or provider is dying, don't disturb. */
538 	if (cp->flags & G_CF_ORPHAN)
539 		return (ENXIO);
540 	if (pp->error)
541 		return (pp->error);
542 
543 	error = 0;
544 	KASSERT(cp->acr || cp->acw,
545 	    ("Consumer with zero access count in g_dev_ioctl"));
546 
547 	i = IOCPARM_LEN(cmd);
548 	switch (cmd) {
549 	case DIOCGSECTORSIZE:
550 		*(u_int *)data = pp->sectorsize;
551 		if (*(u_int *)data == 0)
552 			error = ENOENT;
553 		break;
554 	case DIOCGMEDIASIZE:
555 		*(off_t *)data = pp->mediasize;
556 		if (*(off_t *)data == 0)
557 			error = ENOENT;
558 		break;
559 	case DIOCGFWSECTORS:
560 		error = g_io_getattr("GEOM::fwsectors", cp, &i, data);
561 		if (error == 0 && *(u_int *)data == 0)
562 			error = ENOENT;
563 		break;
564 	case DIOCGFWHEADS:
565 		error = g_io_getattr("GEOM::fwheads", cp, &i, data);
566 		if (error == 0 && *(u_int *)data == 0)
567 			error = ENOENT;
568 		break;
569 	case DIOCSKERNELDUMP:
570 	    {
571 		struct diocskerneldump_arg *kda;
572 		uint8_t *encryptedkey;
573 
574 		kda = (struct diocskerneldump_arg *)data;
575 		if (kda->kda_index == KDA_REMOVE_ALL ||
576 		    kda->kda_index == KDA_REMOVE_DEV ||
577 		    kda->kda_index == KDA_REMOVE) {
578 			error = dumper_remove(devtoname(dev), kda);
579 			explicit_bzero(kda, sizeof(*kda));
580 			break;
581 		}
582 
583 		if (kda->kda_encryption != KERNELDUMP_ENC_NONE) {
584 			if (kda->kda_encryptedkeysize == 0 ||
585 			    kda->kda_encryptedkeysize >
586 			    KERNELDUMP_ENCKEY_MAX_SIZE) {
587 				explicit_bzero(kda, sizeof(*kda));
588 				return (EINVAL);
589 			}
590 			encryptedkey = malloc(kda->kda_encryptedkeysize, M_TEMP,
591 			    M_WAITOK);
592 			error = copyin(kda->kda_encryptedkey, encryptedkey,
593 			    kda->kda_encryptedkeysize);
594 		} else {
595 			encryptedkey = NULL;
596 		}
597 		if (error == 0) {
598 			kda->kda_encryptedkey = encryptedkey;
599 			error = g_dev_setdumpdev(dev, kda);
600 		}
601 		zfree(encryptedkey, M_TEMP);
602 		explicit_bzero(kda, sizeof(*kda));
603 		break;
604 	    }
605 	case DIOCGFLUSH:
606 		error = g_io_flush(cp);
607 		break;
608 	case DIOCGDELETE:
609 		offset = ((off_t *)data)[0];
610 		length = ((off_t *)data)[1];
611 		if ((offset % pp->sectorsize) != 0 ||
612 		    (length % pp->sectorsize) != 0 || length <= 0) {
613 			printf("%s: offset=%jd length=%jd\n", __func__, offset,
614 			    length);
615 			error = EINVAL;
616 			break;
617 		}
618 		while (length > 0) {
619 			chunk = length;
620 			if (g_dev_del_max_sectors != 0 &&
621 			    chunk > g_dev_del_max_sectors * pp->sectorsize) {
622 				chunk = g_dev_del_max_sectors * pp->sectorsize;
623 				if (pp->stripesize > 0) {
624 					odd = (offset + chunk +
625 					    pp->stripeoffset) % pp->stripesize;
626 					if (chunk > odd)
627 						chunk -= odd;
628 				}
629 			}
630 			error = g_delete_data(cp, offset, chunk);
631 			length -= chunk;
632 			offset += chunk;
633 			if (error)
634 				break;
635 			/*
636 			 * Since the request size can be large, the service
637 			 * time can be is likewise.  We make this ioctl
638 			 * interruptible by checking for signals for each bio.
639 			 */
640 			if (SIGPENDING(td))
641 				break;
642 		}
643 		break;
644 	case DIOCGIDENT:
645 		error = g_io_getattr("GEOM::ident", cp, &i, data);
646 		break;
647 	case DIOCGPROVIDERNAME:
648 		strlcpy(data, pp->name, i);
649 		break;
650 	case DIOCGSTRIPESIZE:
651 		*(off_t *)data = pp->stripesize;
652 		break;
653 	case DIOCGSTRIPEOFFSET:
654 		*(off_t *)data = pp->stripeoffset;
655 		break;
656 	case DIOCGPHYSPATH:
657 		error = g_io_getattr("GEOM::physpath", cp, &i, data);
658 		if (error == 0 && *(char *)data == '\0')
659 			error = ENOENT;
660 		break;
661 	case DIOCGATTR: {
662 		struct diocgattr_arg *arg = (struct diocgattr_arg *)data;
663 
664 		if (arg->len > sizeof(arg->value)) {
665 			error = EINVAL;
666 			break;
667 		}
668 		error = g_io_getattr(arg->name, cp, &arg->len, &arg->value);
669 		break;
670 	}
671 	case DIOCZONECMD: {
672 		struct disk_zone_args *zone_args =(struct disk_zone_args *)data;
673 		struct disk_zone_rep_entry *new_entries, *old_entries;
674 		struct disk_zone_report *rep;
675 		size_t alloc_size;
676 
677 		old_entries = NULL;
678 		new_entries = NULL;
679 		rep = NULL;
680 		alloc_size = 0;
681 
682 		if (zone_args->zone_cmd == DISK_ZONE_REPORT_ZONES) {
683 			rep = &zone_args->zone_params.report;
684 #define	MAXENTRIES	(maxphys / sizeof(struct disk_zone_rep_entry))
685 			if (rep->entries_allocated > MAXENTRIES)
686 				rep->entries_allocated = MAXENTRIES;
687 			alloc_size = rep->entries_allocated *
688 			    sizeof(struct disk_zone_rep_entry);
689 			if (alloc_size != 0)
690 				new_entries = g_malloc(alloc_size,
691 				    M_WAITOK | M_ZERO);
692 			old_entries = rep->entries;
693 			rep->entries = new_entries;
694 		}
695 		error = g_io_zonecmd(zone_args, cp);
696 		if (zone_args->zone_cmd == DISK_ZONE_REPORT_ZONES &&
697 		    alloc_size != 0 && error == 0)
698 			error = copyout(new_entries, old_entries, alloc_size);
699 		if (old_entries != NULL && rep != NULL)
700 			rep->entries = old_entries;
701 		g_free(new_entries);
702 		break;
703 	}
704 	default:
705 		if (pp->geom->ioctl != NULL) {
706 			error = pp->geom->ioctl(pp, cmd, data, fflag, td);
707 		} else {
708 			error = ENOIOCTL;
709 		}
710 	}
711 
712 	return (error);
713 }
714 
715 static void
716 g_dev_done(struct bio *bp2)
717 {
718 	struct g_consumer *cp;
719 	struct g_dev_softc *sc;
720 	struct bio *bp;
721 	int active;
722 
723 	cp = bp2->bio_from;
724 	sc = cp->private;
725 	bp = bp2->bio_parent;
726 	bp->bio_error = bp2->bio_error;
727 	bp->bio_completed = bp2->bio_completed;
728 	bp->bio_resid = bp->bio_length - bp2->bio_completed;
729 	if (bp2->bio_cmd == BIO_ZONE)
730 		bcopy(&bp2->bio_zone, &bp->bio_zone, sizeof(bp->bio_zone));
731 
732 	if (bp2->bio_error != 0) {
733 		g_trace(G_T_BIO, "g_dev_done(%p) had error %d",
734 		    bp2, bp2->bio_error);
735 		bp->bio_flags |= BIO_ERROR;
736 	} else {
737 		if (bp->bio_cmd == BIO_READ)
738 			KNOTE_UNLOCKED(&sc->sc_selinfo.si_note, NOTE_READ);
739 		if (bp->bio_cmd == BIO_WRITE)
740 			KNOTE_UNLOCKED(&sc->sc_selinfo.si_note, NOTE_WRITE);
741 		g_trace(G_T_BIO, "g_dev_done(%p/%p) resid %ld completed %jd",
742 		    bp2, bp, bp2->bio_resid, (intmax_t)bp2->bio_completed);
743 	}
744 	g_destroy_bio(bp2);
745 	active = atomic_fetchadd_int(&sc->sc_active, -1) - 1;
746 	if ((active & SC_A_ACTIVE) == 0) {
747 		if ((active & SC_A_OPEN) == 0)
748 			wakeup(&sc->sc_active);
749 		if (active & SC_A_DESTROY)
750 			g_post_event(g_dev_destroy, cp, M_NOWAIT, NULL);
751 	}
752 	biodone(bp);
753 }
754 
755 static void
756 g_dev_strategy(struct bio *bp)
757 {
758 	struct g_consumer *cp;
759 	struct bio *bp2;
760 	struct cdev *dev;
761 	struct g_dev_softc *sc;
762 
763 	KASSERT(bp->bio_cmd == BIO_READ ||
764 	        bp->bio_cmd == BIO_WRITE ||
765 	        bp->bio_cmd == BIO_DELETE ||
766 		bp->bio_cmd == BIO_FLUSH ||
767 		bp->bio_cmd == BIO_ZONE,
768 		("Wrong bio_cmd bio=%p cmd=%d", bp, bp->bio_cmd));
769 	dev = bp->bio_dev;
770 	cp = dev->si_drv2;
771 	KASSERT(cp->acr || cp->acw,
772 	    ("Consumer with zero access count in g_dev_strategy"));
773 	biotrack(bp, __func__);
774 #ifdef INVARIANTS
775 	if ((bp->bio_offset % cp->provider->sectorsize) != 0 ||
776 	    (bp->bio_bcount % cp->provider->sectorsize) != 0) {
777 		bp->bio_resid = bp->bio_bcount;
778 		biofinish(bp, NULL, EINVAL);
779 		return;
780 	}
781 #endif
782 	sc = dev->si_drv1;
783 	KASSERT(sc->sc_open > 0, ("Closed device in g_dev_strategy"));
784 	atomic_add_int(&sc->sc_active, 1);
785 
786 	for (;;) {
787 		/*
788 		 * XXX: This is not an ideal solution, but I believe it to
789 		 * XXX: deadlock safely, all things considered.
790 		 */
791 		bp2 = g_clone_bio(bp);
792 		if (bp2 != NULL)
793 			break;
794 		pause("gdstrat", hz / 10);
795 	}
796 	KASSERT(bp2 != NULL, ("XXX: ENOMEM in a bad place"));
797 	bp2->bio_done = g_dev_done;
798 	g_trace(G_T_BIO,
799 	    "g_dev_strategy(%p/%p) offset %jd length %jd data %p cmd %d",
800 	    bp, bp2, (intmax_t)bp->bio_offset, (intmax_t)bp2->bio_length,
801 	    bp2->bio_data, bp2->bio_cmd);
802 	g_io_request(bp2, cp);
803 	KASSERT(cp->acr || cp->acw,
804 	    ("g_dev_strategy raced with g_dev_close and lost"));
805 
806 }
807 
808 /*
809  * g_dev_callback()
810  *
811  * Called by devfs when asynchronous device destruction is completed.
812  * - Mark that we have no attached device any more.
813  * - If there are no outstanding requests, schedule geom destruction.
814  *   Otherwise destruction will be scheduled later by g_dev_done().
815  */
816 
817 static void
818 g_dev_callback(void *arg)
819 {
820 	struct g_consumer *cp;
821 	struct g_dev_softc *sc;
822 	int active;
823 
824 	cp = arg;
825 	sc = cp->private;
826 	g_trace(G_T_TOPOLOGY, "g_dev_callback(%p(%s))", cp, cp->geom->name);
827 
828 	sc->sc_dev = NULL;
829 	sc->sc_alias = NULL;
830 	active = atomic_fetchadd_int(&sc->sc_active, SC_A_DESTROY);
831 	if ((active & SC_A_ACTIVE) == 0)
832 		g_post_event(g_dev_destroy, cp, M_WAITOK, NULL);
833 }
834 
835 /*
836  * g_dev_orphan()
837  *
838  * Called from below when the provider orphaned us.
839  * - Clear any dump settings.
840  * - Request asynchronous device destruction to prevent any more requests
841  *   from coming in.  The provider is already marked with an error, so
842  *   anything which comes in the interim will be returned immediately.
843  */
844 
845 static void
846 g_dev_orphan(struct g_consumer *cp)
847 {
848 	struct cdev *dev;
849 	struct g_dev_softc *sc;
850 
851 	g_topology_assert();
852 	sc = cp->private;
853 	dev = sc->sc_dev;
854 	g_trace(G_T_TOPOLOGY, "g_dev_orphan(%p(%s))", cp, cp->geom->name);
855 
856 	/* Reset any dump-area set on this device */
857 	if (dev->si_flags & SI_DUMPDEV) {
858 		struct diocskerneldump_arg kda;
859 
860 		bzero(&kda, sizeof(kda));
861 		kda.kda_index = KDA_REMOVE_DEV;
862 		(void)dumper_remove(devtoname(dev), &kda);
863 	}
864 
865 	/* Destroy the struct cdev *so we get no more requests */
866 	delist_dev(dev);
867 	destroy_dev_sched_cb(dev, g_dev_callback, cp);
868 }
869 
870 static void
871 gdev_filter_detach(struct knote *kn)
872 {
873 	struct g_dev_softc *sc;
874 
875 	sc = kn->kn_hook;
876 
877 	knlist_remove(&sc->sc_selinfo.si_note, kn, 0);
878 }
879 
880 static int
881 gdev_filter_vnode(struct knote *kn, long hint)
882 {
883 	kn->kn_fflags |= kn->kn_sfflags & hint;
884 
885 	return (kn->kn_fflags != 0);
886 }
887 
888 static int
889 g_dev_kqfilter(struct cdev *dev, struct knote *kn)
890 {
891 	struct g_dev_softc *sc;
892 
893 	sc = dev->si_drv1;
894 
895 	if (kn->kn_filter != EVFILT_VNODE)
896 		return (EINVAL);
897 
898 #define SUPPORTED_EVENTS (NOTE_ATTRIB | NOTE_OPEN | NOTE_CLOSE | \
899     NOTE_CLOSE_WRITE | NOTE_READ | NOTE_WRITE)
900 	if (kn->kn_sfflags & ~SUPPORTED_EVENTS)
901 		return (EOPNOTSUPP);
902 
903 	kn->kn_fop = &gdev_filterops_vnode;
904 	kn->kn_hook = sc;
905 	knlist_add(&sc->sc_selinfo.si_note, kn, 0);
906 
907 	return (0);
908 }
909 
910 DECLARE_GEOM_CLASS(g_dev_class, g_dev);
911