geom_dev.c revision 291548
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
36#include <sys/cdefs.h>
37__FBSDID("$FreeBSD: stable/10/sys/geom/geom_dev.c 291548 2015-12-01 00:53:03Z smh $");
38
39#include <sys/param.h>
40#include <sys/systm.h>
41#include <sys/malloc.h>
42#include <sys/kernel.h>
43#include <sys/conf.h>
44#include <sys/ctype.h>
45#include <sys/bio.h>
46#include <sys/bus.h>
47#include <sys/lock.h>
48#include <sys/mutex.h>
49#include <sys/proc.h>
50#include <sys/errno.h>
51#include <sys/time.h>
52#include <sys/disk.h>
53#include <sys/fcntl.h>
54#include <sys/limits.h>
55#include <sys/sysctl.h>
56#include <geom/geom.h>
57#include <geom/geom_int.h>
58#include <machine/stdarg.h>
59
60struct g_dev_softc {
61	struct mtx	 sc_mtx;
62	struct cdev	*sc_dev;
63	struct cdev	*sc_alias;
64	int		 sc_open;
65	int		 sc_active;
66};
67
68static d_open_t		g_dev_open;
69static d_close_t	g_dev_close;
70static d_strategy_t	g_dev_strategy;
71static d_ioctl_t	g_dev_ioctl;
72
73static struct cdevsw g_dev_cdevsw = {
74	.d_version =	D_VERSION,
75	.d_open =	g_dev_open,
76	.d_close =	g_dev_close,
77	.d_read =	physread,
78	.d_write =	physwrite,
79	.d_ioctl =	g_dev_ioctl,
80	.d_strategy =	g_dev_strategy,
81	.d_name =	"g_dev",
82	.d_flags =	D_DISK | D_TRACKCLOSE,
83};
84
85static g_init_t g_dev_init;
86static g_fini_t g_dev_fini;
87static g_taste_t g_dev_taste;
88static g_orphan_t g_dev_orphan;
89static g_attrchanged_t g_dev_attrchanged;
90
91static struct g_class g_dev_class	= {
92	.name = "DEV",
93	.version = G_VERSION,
94	.init = g_dev_init,
95	.fini = g_dev_fini,
96	.taste = g_dev_taste,
97	.orphan = g_dev_orphan,
98	.attrchanged = g_dev_attrchanged
99};
100
101/*
102 * We target 262144 (8 x 32768) sectors by default as this significantly
103 * increases the throughput on commonly used SSD's with a marginal
104 * increase in non-interruptible request latency.
105 */
106static uint64_t g_dev_del_max_sectors = 262144;
107SYSCTL_DECL(_kern_geom);
108SYSCTL_NODE(_kern_geom, OID_AUTO, dev, CTLFLAG_RW, 0, "GEOM_DEV stuff");
109SYSCTL_QUAD(_kern_geom_dev, OID_AUTO, delete_max_sectors, CTLFLAG_RW,
110    &g_dev_del_max_sectors, 0, "Maximum number of sectors in a single "
111    "delete request sent to the provider. Larger requests are chunked "
112    "so they can be interrupted. (0 = disable chunking)");
113
114static char *dumpdev = NULL;
115static void
116g_dev_init(struct g_class *mp)
117{
118
119	dumpdev = getenv("dumpdev");
120}
121
122static void
123g_dev_fini(struct g_class *mp)
124{
125
126	freeenv(dumpdev);
127	dumpdev = NULL;
128}
129
130static int
131g_dev_setdumpdev(struct cdev *dev, struct thread *td)
132{
133	struct g_kerneldump kd;
134	struct g_consumer *cp;
135	int error, len;
136
137	if (dev == NULL)
138		return (set_dumper(NULL, NULL, td));
139
140	cp = dev->si_drv2;
141	len = sizeof(kd);
142	kd.offset = 0;
143	kd.length = OFF_MAX;
144	error = g_io_getattr("GEOM::kerneldump", cp, &len, &kd);
145	if (error == 0) {
146		error = set_dumper(&kd.di, devtoname(dev), td);
147		if (error == 0)
148			dev->si_flags |= SI_DUMPDEV;
149	}
150	return (error);
151}
152
153static int
154init_dumpdev(struct cdev *dev)
155{
156	struct g_consumer *cp;
157	const char *devprefix = "/dev/", *devname;
158	int error;
159	size_t len;
160
161	if (dumpdev == NULL)
162		return (0);
163
164	len = strlen(devprefix);
165	devname = devtoname(dev);
166	if (strcmp(devname, dumpdev) != 0 &&
167	   (strncmp(dumpdev, devprefix, len) != 0 ||
168	    strcmp(devname, dumpdev + len) != 0))
169		return (0);
170
171	cp = (struct g_consumer *)dev->si_drv2;
172	error = g_access(cp, 1, 0, 0);
173	if (error != 0)
174		return (error);
175
176	error = g_dev_setdumpdev(dev, curthread);
177	if (error == 0) {
178		freeenv(dumpdev);
179		dumpdev = NULL;
180	}
181
182	(void)g_access(cp, -1, 0, 0);
183
184	return (error);
185}
186
187static void
188g_dev_destroy(void *arg, int flags __unused)
189{
190	struct g_consumer *cp;
191	struct g_geom *gp;
192	struct g_dev_softc *sc;
193	char buf[SPECNAMELEN + 6];
194
195	g_topology_assert();
196	cp = arg;
197	gp = cp->geom;
198	sc = cp->private;
199	g_trace(G_T_TOPOLOGY, "g_dev_destroy(%p(%s))", cp, gp->name);
200	snprintf(buf, sizeof(buf), "cdev=%s", gp->name);
201	devctl_notify_f("GEOM", "DEV", "DESTROY", buf, M_WAITOK);
202	if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
203		g_access(cp, -cp->acr, -cp->acw, -cp->ace);
204	g_detach(cp);
205	g_destroy_consumer(cp);
206	g_destroy_geom(gp);
207	mtx_destroy(&sc->sc_mtx);
208	g_free(sc);
209}
210
211void
212g_dev_print(void)
213{
214	struct g_geom *gp;
215	char const *p = "";
216
217	LIST_FOREACH(gp, &g_dev_class.geom, geom) {
218		printf("%s%s", p, gp->name);
219		p = " ";
220	}
221	printf("\n");
222}
223
224static void
225g_dev_attrchanged(struct g_consumer *cp, const char *attr)
226{
227	struct g_dev_softc *sc;
228	struct cdev *dev;
229	char buf[SPECNAMELEN + 6];
230
231	sc = cp->private;
232	if (strcmp(attr, "GEOM::media") == 0) {
233		dev = sc->sc_dev;
234		snprintf(buf, sizeof(buf), "cdev=%s", dev->si_name);
235		devctl_notify_f("DEVFS", "CDEV", "MEDIACHANGE", buf, M_WAITOK);
236		devctl_notify_f("GEOM", "DEV", "MEDIACHANGE", buf, M_WAITOK);
237		dev = sc->sc_alias;
238		if (dev != NULL) {
239			snprintf(buf, sizeof(buf), "cdev=%s", dev->si_name);
240			devctl_notify_f("DEVFS", "CDEV", "MEDIACHANGE", buf,
241			    M_WAITOK);
242			devctl_notify_f("GEOM", "DEV", "MEDIACHANGE", buf,
243			    M_WAITOK);
244		}
245		return;
246	}
247
248	if (strcmp(attr, "GEOM::physpath") != 0)
249		return;
250
251	if (g_access(cp, 1, 0, 0) == 0) {
252		char *physpath;
253		int error, physpath_len;
254
255		physpath_len = MAXPATHLEN;
256		physpath = g_malloc(physpath_len, M_WAITOK|M_ZERO);
257		error =
258		    g_io_getattr("GEOM::physpath", cp, &physpath_len, physpath);
259		g_access(cp, -1, 0, 0);
260		if (error == 0 && strlen(physpath) != 0) {
261			struct cdev *old_alias_dev;
262			struct cdev **alias_devp;
263
264			dev = sc->sc_dev;
265			old_alias_dev = sc->sc_alias;
266			alias_devp = (struct cdev **)&sc->sc_alias;
267			make_dev_physpath_alias(MAKEDEV_WAITOK, alias_devp,
268			    dev, old_alias_dev, physpath);
269		} else if (sc->sc_alias) {
270			destroy_dev((struct cdev *)sc->sc_alias);
271			sc->sc_alias = NULL;
272		}
273		g_free(physpath);
274	}
275}
276
277struct g_provider *
278g_dev_getprovider(struct cdev *dev)
279{
280	struct g_consumer *cp;
281
282	g_topology_assert();
283	if (dev == NULL)
284		return (NULL);
285	if (dev->si_devsw != &g_dev_cdevsw)
286		return (NULL);
287	cp = dev->si_drv2;
288	return (cp->provider);
289}
290
291static struct g_geom *
292g_dev_taste(struct g_class *mp, struct g_provider *pp, int insist __unused)
293{
294	struct g_geom *gp;
295	struct g_consumer *cp;
296	struct g_dev_softc *sc;
297	int error, len;
298	struct cdev *dev, *adev;
299	char buf[SPECNAMELEN + 6], *val;
300
301	g_trace(G_T_TOPOLOGY, "dev_taste(%s,%s)", mp->name, pp->name);
302	g_topology_assert();
303	gp = g_new_geomf(mp, "%s", pp->name);
304	sc = g_malloc(sizeof(*sc), M_WAITOK | M_ZERO);
305	mtx_init(&sc->sc_mtx, "g_dev", NULL, MTX_DEF);
306	cp = g_new_consumer(gp);
307	cp->private = sc;
308	cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE;
309	error = g_attach(cp, pp);
310	KASSERT(error == 0,
311	    ("g_dev_taste(%s) failed to g_attach, err=%d", pp->name, error));
312	error = make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK, &dev,
313	    &g_dev_cdevsw, NULL, UID_ROOT, GID_OPERATOR, 0640, "%s", gp->name);
314	if (error != 0) {
315		printf("%s: make_dev_p() failed (gp->name=%s, error=%d)\n",
316		    __func__, gp->name, error);
317		g_detach(cp);
318		g_destroy_consumer(cp);
319		g_destroy_geom(gp);
320		mtx_destroy(&sc->sc_mtx);
321		g_free(sc);
322		return (NULL);
323	}
324	dev->si_flags |= SI_UNMAPPED;
325	sc->sc_dev = dev;
326
327	/* Search for device alias name and create it if found. */
328	adev = NULL;
329	for (len = MIN(strlen(gp->name), sizeof(buf) - 15); len > 0; len--) {
330		snprintf(buf, sizeof(buf), "kern.devalias.%s", gp->name);
331		buf[14 + len] = 0;
332		val = getenv(buf);
333		if (val != NULL) {
334			snprintf(buf, sizeof(buf), "%s%s",
335			    val, gp->name + len);
336			freeenv(val);
337			make_dev_alias_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK,
338			    &adev, dev, "%s", buf);
339			adev->si_flags |= SI_UNMAPPED;
340			break;
341		}
342	}
343
344	dev->si_iosize_max = MAXPHYS;
345	dev->si_drv2 = cp;
346	error = init_dumpdev(dev);
347	if (error != 0)
348		printf("%s: init_dumpdev() failed (gp->name=%s, error=%d)\n",
349		    __func__, gp->name, error);
350	if (adev != NULL) {
351		adev->si_iosize_max = MAXPHYS;
352		adev->si_drv2 = cp;
353		init_dumpdev(adev);
354	}
355
356	g_dev_attrchanged(cp, "GEOM::physpath");
357	snprintf(buf, sizeof(buf), "cdev=%s", gp->name);
358	devctl_notify_f("GEOM", "DEV", "CREATE", buf, M_WAITOK);
359
360	return (gp);
361}
362
363static int
364g_dev_open(struct cdev *dev, int flags, int fmt, struct thread *td)
365{
366	struct g_consumer *cp;
367	struct g_dev_softc *sc;
368	int error, r, w, e;
369
370	cp = dev->si_drv2;
371	if (cp == NULL)
372		return(ENXIO);		/* g_dev_taste() not done yet */
373	g_trace(G_T_ACCESS, "g_dev_open(%s, %d, %d, %p)",
374	    cp->geom->name, flags, fmt, td);
375
376	r = flags & FREAD ? 1 : 0;
377	w = flags & FWRITE ? 1 : 0;
378#ifdef notyet
379	e = flags & O_EXCL ? 1 : 0;
380#else
381	e = 0;
382#endif
383
384	/*
385	 * This happens on attempt to open a device node with O_EXEC.
386	 */
387	if (r + w + e == 0)
388		return (EINVAL);
389
390	if (w) {
391		/*
392		 * When running in very secure mode, do not allow
393		 * opens for writing of any disks.
394		 */
395		error = securelevel_ge(td->td_ucred, 2);
396		if (error)
397			return (error);
398	}
399	g_topology_lock();
400	error = g_access(cp, r, w, e);
401	g_topology_unlock();
402	if (error == 0) {
403		sc = cp->private;
404		mtx_lock(&sc->sc_mtx);
405		if (sc->sc_open == 0 && sc->sc_active != 0)
406			wakeup(&sc->sc_active);
407		sc->sc_open += r + w + e;
408		mtx_unlock(&sc->sc_mtx);
409	}
410	return(error);
411}
412
413static int
414g_dev_close(struct cdev *dev, int flags, int fmt, struct thread *td)
415{
416	struct g_consumer *cp;
417	struct g_dev_softc *sc;
418	int error, r, w, e;
419
420	cp = dev->si_drv2;
421	if (cp == NULL)
422		return(ENXIO);
423	g_trace(G_T_ACCESS, "g_dev_close(%s, %d, %d, %p)",
424	    cp->geom->name, flags, fmt, td);
425
426	r = flags & FREAD ? -1 : 0;
427	w = flags & FWRITE ? -1 : 0;
428#ifdef notyet
429	e = flags & O_EXCL ? -1 : 0;
430#else
431	e = 0;
432#endif
433
434	/*
435	 * The vgonel(9) - caused by eg. forced unmount of devfs - calls
436	 * VOP_CLOSE(9) on devfs vnode without any FREAD or FWRITE flags,
437	 * which would result in zero deltas, which in turn would cause
438	 * panic in g_access(9).
439	 *
440	 * Note that we cannot zero the counters (ie. do "r = cp->acr"
441	 * etc) instead, because the consumer might be opened in another
442	 * devfs instance.
443	 */
444	if (r + w + e == 0)
445		return (EINVAL);
446
447	sc = cp->private;
448	mtx_lock(&sc->sc_mtx);
449	sc->sc_open += r + w + e;
450	while (sc->sc_open == 0 && sc->sc_active != 0)
451		msleep(&sc->sc_active, &sc->sc_mtx, 0, "PRIBIO", 0);
452	mtx_unlock(&sc->sc_mtx);
453	g_topology_lock();
454	error = g_access(cp, r, w, e);
455	g_topology_unlock();
456	return (error);
457}
458
459/*
460 * XXX: Until we have unmessed the ioctl situation, there is a race against
461 * XXX: a concurrent orphanization.  We cannot close it by holding topology
462 * XXX: since that would prevent us from doing our job, and stalling events
463 * XXX: will break (actually: stall) the BSD disklabel hacks.
464 */
465static int
466g_dev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
467{
468	struct g_consumer *cp;
469	struct g_provider *pp;
470	off_t offset, length, chunk;
471	int i, error;
472
473	cp = dev->si_drv2;
474	pp = cp->provider;
475
476	error = 0;
477	KASSERT(cp->acr || cp->acw,
478	    ("Consumer with zero access count in g_dev_ioctl"));
479
480	i = IOCPARM_LEN(cmd);
481	switch (cmd) {
482	case DIOCGSECTORSIZE:
483		*(u_int *)data = cp->provider->sectorsize;
484		if (*(u_int *)data == 0)
485			error = ENOENT;
486		break;
487	case DIOCGMEDIASIZE:
488		*(off_t *)data = cp->provider->mediasize;
489		if (*(off_t *)data == 0)
490			error = ENOENT;
491		break;
492	case DIOCGFWSECTORS:
493		error = g_io_getattr("GEOM::fwsectors", cp, &i, data);
494		if (error == 0 && *(u_int *)data == 0)
495			error = ENOENT;
496		break;
497	case DIOCGFWHEADS:
498		error = g_io_getattr("GEOM::fwheads", cp, &i, data);
499		if (error == 0 && *(u_int *)data == 0)
500			error = ENOENT;
501		break;
502	case DIOCGFRONTSTUFF:
503		error = g_io_getattr("GEOM::frontstuff", cp, &i, data);
504		break;
505	case DIOCSKERNELDUMP:
506		if (*(u_int *)data == 0)
507			error = g_dev_setdumpdev(NULL, td);
508		else
509			error = g_dev_setdumpdev(dev, td);
510		break;
511	case DIOCGFLUSH:
512		error = g_io_flush(cp);
513		break;
514	case DIOCGDELETE:
515		offset = ((off_t *)data)[0];
516		length = ((off_t *)data)[1];
517		if ((offset % cp->provider->sectorsize) != 0 ||
518		    (length % cp->provider->sectorsize) != 0 || length <= 0) {
519			printf("%s: offset=%jd length=%jd\n", __func__, offset,
520			    length);
521			error = EINVAL;
522			break;
523		}
524		while (length > 0) {
525			chunk = length;
526			if (g_dev_del_max_sectors != 0 && chunk >
527			    g_dev_del_max_sectors * cp->provider->sectorsize) {
528				chunk = g_dev_del_max_sectors *
529				    cp->provider->sectorsize;
530			}
531			error = g_delete_data(cp, offset, chunk);
532			length -= chunk;
533			offset += chunk;
534			if (error)
535				break;
536			/*
537			 * Since the request size can be large, the service
538			 * time can be is likewise.  We make this ioctl
539			 * interruptible by checking for signals for each bio.
540			 */
541			if (SIGPENDING(td))
542				break;
543		}
544		break;
545	case DIOCGIDENT:
546		error = g_io_getattr("GEOM::ident", cp, &i, data);
547		break;
548	case DIOCGPROVIDERNAME:
549		if (pp == NULL)
550			return (ENOENT);
551		strlcpy(data, pp->name, i);
552		break;
553	case DIOCGSTRIPESIZE:
554		*(off_t *)data = cp->provider->stripesize;
555		break;
556	case DIOCGSTRIPEOFFSET:
557		*(off_t *)data = cp->provider->stripeoffset;
558		break;
559	case DIOCGPHYSPATH:
560		error = g_io_getattr("GEOM::physpath", cp, &i, data);
561		if (error == 0 && *(char *)data == '\0')
562			error = ENOENT;
563		break;
564	case DIOCGATTR: {
565		struct diocgattr_arg *arg = (struct diocgattr_arg *)data;
566
567		if (arg->len > sizeof(arg->value)) {
568			error = EINVAL;
569			break;
570		}
571		error = g_io_getattr(arg->name, cp, &arg->len, &arg->value);
572		break;
573	}
574	default:
575		if (cp->provider->geom->ioctl != NULL) {
576			error = cp->provider->geom->ioctl(cp->provider, cmd, data, fflag, td);
577		} else {
578			error = ENOIOCTL;
579		}
580	}
581
582	return (error);
583}
584
585static void
586g_dev_done(struct bio *bp2)
587{
588	struct g_consumer *cp;
589	struct g_dev_softc *sc;
590	struct bio *bp;
591	int destroy;
592
593	cp = bp2->bio_from;
594	sc = cp->private;
595	bp = bp2->bio_parent;
596	bp->bio_error = bp2->bio_error;
597	bp->bio_completed = bp2->bio_completed;
598	bp->bio_resid = bp->bio_length - bp2->bio_completed;
599	if (bp2->bio_error != 0) {
600		g_trace(G_T_BIO, "g_dev_done(%p) had error %d",
601		    bp2, bp2->bio_error);
602		bp->bio_flags |= BIO_ERROR;
603	} else {
604		g_trace(G_T_BIO, "g_dev_done(%p/%p) resid %ld completed %jd",
605		    bp2, bp, bp2->bio_resid, (intmax_t)bp2->bio_completed);
606	}
607	g_destroy_bio(bp2);
608	destroy = 0;
609	mtx_lock(&sc->sc_mtx);
610	if ((--sc->sc_active) == 0) {
611		if (sc->sc_open == 0)
612			wakeup(&sc->sc_active);
613		if (sc->sc_dev == NULL)
614			destroy = 1;
615	}
616	mtx_unlock(&sc->sc_mtx);
617	if (destroy)
618		g_post_event(g_dev_destroy, cp, M_NOWAIT, NULL);
619	biodone(bp);
620}
621
622static void
623g_dev_strategy(struct bio *bp)
624{
625	struct g_consumer *cp;
626	struct bio *bp2;
627	struct cdev *dev;
628	struct g_dev_softc *sc;
629
630	KASSERT(bp->bio_cmd == BIO_READ ||
631	        bp->bio_cmd == BIO_WRITE ||
632	        bp->bio_cmd == BIO_DELETE ||
633		bp->bio_cmd == BIO_FLUSH,
634		("Wrong bio_cmd bio=%p cmd=%d", bp, bp->bio_cmd));
635	dev = bp->bio_dev;
636	cp = dev->si_drv2;
637	sc = cp->private;
638	KASSERT(cp->acr || cp->acw,
639	    ("Consumer with zero access count in g_dev_strategy"));
640#ifdef INVARIANTS
641	if ((bp->bio_offset % cp->provider->sectorsize) != 0 ||
642	    (bp->bio_bcount % cp->provider->sectorsize) != 0) {
643		bp->bio_resid = bp->bio_bcount;
644		biofinish(bp, NULL, EINVAL);
645		return;
646	}
647#endif
648	mtx_lock(&sc->sc_mtx);
649	KASSERT(sc->sc_open > 0, ("Closed device in g_dev_strategy"));
650	sc->sc_active++;
651	mtx_unlock(&sc->sc_mtx);
652
653	for (;;) {
654		/*
655		 * XXX: This is not an ideal solution, but I belive it to
656		 * XXX: deadlock safe, all things considered.
657		 */
658		bp2 = g_clone_bio(bp);
659		if (bp2 != NULL)
660			break;
661		pause("gdstrat", hz / 10);
662	}
663	KASSERT(bp2 != NULL, ("XXX: ENOMEM in a bad place"));
664	bp2->bio_done = g_dev_done;
665	g_trace(G_T_BIO,
666	    "g_dev_strategy(%p/%p) offset %jd length %jd data %p cmd %d",
667	    bp, bp2, (intmax_t)bp->bio_offset, (intmax_t)bp2->bio_length,
668	    bp2->bio_data, bp2->bio_cmd);
669	g_io_request(bp2, cp);
670	KASSERT(cp->acr || cp->acw,
671	    ("g_dev_strategy raced with g_dev_close and lost"));
672
673}
674
675/*
676 * g_dev_callback()
677 *
678 * Called by devfs when asynchronous device destruction is completed.
679 * - Mark that we have no attached device any more.
680 * - If there are no outstanding requests, schedule geom destruction.
681 *   Otherwise destruction will be scheduled later by g_dev_done().
682 */
683
684static void
685g_dev_callback(void *arg)
686{
687	struct g_consumer *cp;
688	struct g_dev_softc *sc;
689	int destroy;
690
691	cp = arg;
692	sc = cp->private;
693	g_trace(G_T_TOPOLOGY, "g_dev_callback(%p(%s))", cp, cp->geom->name);
694
695	mtx_lock(&sc->sc_mtx);
696	sc->sc_dev = NULL;
697	sc->sc_alias = NULL;
698	destroy = (sc->sc_active == 0);
699	mtx_unlock(&sc->sc_mtx);
700	if (destroy)
701		g_post_event(g_dev_destroy, cp, M_WAITOK, NULL);
702}
703
704/*
705 * g_dev_orphan()
706 *
707 * Called from below when the provider orphaned us.
708 * - Clear any dump settings.
709 * - Request asynchronous device destruction to prevent any more requests
710 *   from coming in.  The provider is already marked with an error, so
711 *   anything which comes in in the interrim will be returned immediately.
712 */
713
714static void
715g_dev_orphan(struct g_consumer *cp)
716{
717	struct cdev *dev;
718	struct g_dev_softc *sc;
719
720	g_topology_assert();
721	sc = cp->private;
722	dev = sc->sc_dev;
723	g_trace(G_T_TOPOLOGY, "g_dev_orphan(%p(%s))", cp, cp->geom->name);
724
725	/* Reset any dump-area set on this device */
726	if (dev->si_flags & SI_DUMPDEV)
727		(void)set_dumper(NULL, NULL, curthread);
728
729	/* Destroy the struct cdev *so we get no more requests */
730	destroy_dev_sched_cb(dev, g_dev_callback, cp);
731}
732
733DECLARE_GEOM_CLASS(g_dev_class, g_dev);
734