xref: /freebsd/sys/geom/geom_disk.c (revision 9268022b74279434ed6300244e3f977e56a8ceb5)
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("$FreeBSD$");
38 
39 #include "opt_geom.h"
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/kernel.h>
44 #include <sys/sysctl.h>
45 #include <sys/bio.h>
46 #include <sys/ctype.h>
47 #include <sys/fcntl.h>
48 #include <sys/malloc.h>
49 #include <sys/sbuf.h>
50 #include <sys/devicestat.h>
51 #include <machine/md_var.h>
52 
53 #include <sys/lock.h>
54 #include <sys/mutex.h>
55 #include <geom/geom.h>
56 #include <geom/geom_disk.h>
57 #include <geom/geom_int.h>
58 
59 #include <dev/led/led.h>
60 
61 struct g_disk_softc {
62 	struct mtx		 done_mtx;
63 	struct disk		*dp;
64 	struct sysctl_ctx_list	sysctl_ctx;
65 	struct sysctl_oid	*sysctl_tree;
66 	char			led[64];
67 	uint32_t		state;
68 	struct mtx		 start_mtx;
69 };
70 
71 static g_access_t g_disk_access;
72 static g_start_t g_disk_start;
73 static g_ioctl_t g_disk_ioctl;
74 static g_dumpconf_t g_disk_dumpconf;
75 static g_provgone_t g_disk_providergone;
76 
77 static struct g_class g_disk_class = {
78 	.name = G_DISK_CLASS_NAME,
79 	.version = G_VERSION,
80 	.start = g_disk_start,
81 	.access = g_disk_access,
82 	.ioctl = g_disk_ioctl,
83 	.providergone = g_disk_providergone,
84 	.dumpconf = g_disk_dumpconf,
85 };
86 
87 SYSCTL_DECL(_kern_geom);
88 static SYSCTL_NODE(_kern_geom, OID_AUTO, disk, CTLFLAG_RW, 0,
89     "GEOM_DISK stuff");
90 
91 DECLARE_GEOM_CLASS(g_disk_class, g_disk);
92 
93 static int
94 g_disk_access(struct g_provider *pp, int r, int w, int e)
95 {
96 	struct disk *dp;
97 	struct g_disk_softc *sc;
98 	int error;
99 
100 	g_trace(G_T_ACCESS, "g_disk_access(%s, %d, %d, %d)",
101 	    pp->name, r, w, e);
102 	g_topology_assert();
103 	sc = pp->private;
104 	if (sc == NULL || (dp = sc->dp) == NULL || dp->d_destroyed) {
105 		/*
106 		 * Allow decreasing access count even if disk is not
107 		 * avaliable anymore.
108 		 */
109 		if (r <= 0 && w <= 0 && e <= 0)
110 			return (0);
111 		return (ENXIO);
112 	}
113 	r += pp->acr;
114 	w += pp->acw;
115 	e += pp->ace;
116 	error = 0;
117 	if ((pp->acr + pp->acw + pp->ace) == 0 && (r + w + e) > 0) {
118 		if (dp->d_open != NULL) {
119 			error = dp->d_open(dp);
120 			if (bootverbose && error != 0)
121 				printf("Opened disk %s -> %d\n",
122 				    pp->name, error);
123 			if (error != 0)
124 				return (error);
125 		}
126 		pp->mediasize = dp->d_mediasize;
127 		pp->sectorsize = dp->d_sectorsize;
128 		if (dp->d_maxsize == 0) {
129 			printf("WARNING: Disk drive %s%d has no d_maxsize\n",
130 			    dp->d_name, dp->d_unit);
131 			dp->d_maxsize = DFLTPHYS;
132 		}
133 		if (dp->d_delmaxsize == 0) {
134 			if (bootverbose && dp->d_flags & DISKFLAG_CANDELETE) {
135 				printf("WARNING: Disk drive %s%d has no "
136 				    "d_delmaxsize\n", dp->d_name, dp->d_unit);
137 			}
138 			dp->d_delmaxsize = dp->d_maxsize;
139 		}
140 		pp->stripeoffset = dp->d_stripeoffset;
141 		pp->stripesize = dp->d_stripesize;
142 		dp->d_flags |= DISKFLAG_OPEN;
143 	} else if ((pp->acr + pp->acw + pp->ace) > 0 && (r + w + e) == 0) {
144 		if (dp->d_close != NULL) {
145 			error = dp->d_close(dp);
146 			if (error != 0)
147 				printf("Closed disk %s -> %d\n",
148 				    pp->name, error);
149 		}
150 		sc->state = G_STATE_ACTIVE;
151 		if (sc->led[0] != 0)
152 			led_set(sc->led, "0");
153 		dp->d_flags &= ~DISKFLAG_OPEN;
154 	}
155 	return (error);
156 }
157 
158 static void
159 g_disk_kerneldump(struct bio *bp, struct disk *dp)
160 {
161 	struct g_kerneldump *gkd;
162 	struct g_geom *gp;
163 
164 	gkd = (struct g_kerneldump*)bp->bio_data;
165 	gp = bp->bio_to->geom;
166 	g_trace(G_T_TOPOLOGY, "g_disk_kerneldump(%s, %jd, %jd)",
167 		gp->name, (intmax_t)gkd->offset, (intmax_t)gkd->length);
168 	if (dp->d_dump == NULL) {
169 		g_io_deliver(bp, ENODEV);
170 		return;
171 	}
172 	gkd->di.dumper = dp->d_dump;
173 	gkd->di.priv = dp;
174 	gkd->di.blocksize = dp->d_sectorsize;
175 	gkd->di.maxiosize = dp->d_maxsize;
176 	gkd->di.mediaoffset = gkd->offset;
177 	if ((gkd->offset + gkd->length) > dp->d_mediasize)
178 		gkd->length = dp->d_mediasize - gkd->offset;
179 	gkd->di.mediasize = gkd->length;
180 	g_io_deliver(bp, 0);
181 }
182 
183 static void
184 g_disk_setstate(struct bio *bp, struct g_disk_softc *sc)
185 {
186 	const char *cmd;
187 
188 	memcpy(&sc->state, bp->bio_data, sizeof(sc->state));
189 	if (sc->led[0] != 0) {
190 		switch (sc->state) {
191 		case G_STATE_FAILED:
192 			cmd = "1";
193 			break;
194 		case G_STATE_REBUILD:
195 			cmd = "f5";
196 			break;
197 		case G_STATE_RESYNC:
198 			cmd = "f1";
199 			break;
200 		default:
201 			cmd = "0";
202 			break;
203 		}
204 		led_set(sc->led, cmd);
205 	}
206 	g_io_deliver(bp, 0);
207 }
208 
209 static void
210 g_disk_done(struct bio *bp)
211 {
212 	struct bintime now;
213 	struct bio *bp2;
214 	struct g_disk_softc *sc;
215 
216 	/* See "notes" for why we need a mutex here */
217 	/* XXX: will witness accept a mix of Giant/unGiant drivers here ? */
218 	bp2 = bp->bio_parent;
219 	sc = bp2->bio_to->private;
220 	bp->bio_completed = bp->bio_length - bp->bio_resid;
221 	binuptime(&now);
222 	mtx_lock(&sc->done_mtx);
223 	if (bp2->bio_error == 0)
224 		bp2->bio_error = bp->bio_error;
225 	bp2->bio_completed += bp->bio_completed;
226 	if ((bp->bio_cmd & (BIO_READ|BIO_WRITE|BIO_DELETE|BIO_FLUSH)) != 0)
227 		devstat_end_transaction_bio_bt(sc->dp->d_devstat, bp, &now);
228 	bp2->bio_inbed++;
229 	if (bp2->bio_children == bp2->bio_inbed) {
230 		mtx_unlock(&sc->done_mtx);
231 		bp2->bio_resid = bp2->bio_bcount - bp2->bio_completed;
232 		g_io_deliver(bp2, bp2->bio_error);
233 	} else
234 		mtx_unlock(&sc->done_mtx);
235 	g_destroy_bio(bp);
236 }
237 
238 static int
239 g_disk_ioctl(struct g_provider *pp, u_long cmd, void * data, int fflag, struct thread *td)
240 {
241 	struct disk *dp;
242 	struct g_disk_softc *sc;
243 	int error;
244 
245 	sc = pp->private;
246 	dp = sc->dp;
247 
248 	if (dp->d_ioctl == NULL)
249 		return (ENOIOCTL);
250 	error = dp->d_ioctl(dp, cmd, data, fflag, td);
251 	return (error);
252 }
253 
254 static void
255 g_disk_start(struct bio *bp)
256 {
257 	struct bio *bp2, *bp3;
258 	struct disk *dp;
259 	struct g_disk_softc *sc;
260 	int error;
261 	off_t off;
262 
263 	sc = bp->bio_to->private;
264 	if (sc == NULL || (dp = sc->dp) == NULL || dp->d_destroyed) {
265 		g_io_deliver(bp, ENXIO);
266 		return;
267 	}
268 	error = EJUSTRETURN;
269 	switch(bp->bio_cmd) {
270 	case BIO_DELETE:
271 		if (!(dp->d_flags & DISKFLAG_CANDELETE)) {
272 			error = EOPNOTSUPP;
273 			break;
274 		}
275 		/* fall-through */
276 	case BIO_READ:
277 	case BIO_WRITE:
278 		off = 0;
279 		bp3 = NULL;
280 		bp2 = g_clone_bio(bp);
281 		if (bp2 == NULL) {
282 			error = ENOMEM;
283 			break;
284 		}
285 		do {
286 			off_t d_maxsize;
287 
288 			d_maxsize = (bp->bio_cmd == BIO_DELETE) ?
289 			    dp->d_delmaxsize : dp->d_maxsize;
290 			bp2->bio_offset += off;
291 			bp2->bio_length -= off;
292 			if ((bp->bio_flags & BIO_UNMAPPED) == 0) {
293 				bp2->bio_data += off;
294 			} else {
295 				KASSERT((dp->d_flags & DISKFLAG_UNMAPPED_BIO)
296 				    != 0,
297 				    ("unmapped bio not supported by disk %s",
298 				    dp->d_name));
299 				bp2->bio_ma += off / PAGE_SIZE;
300 				bp2->bio_ma_offset += off;
301 				bp2->bio_ma_offset %= PAGE_SIZE;
302 				bp2->bio_ma_n -= off / PAGE_SIZE;
303 			}
304 			if (bp2->bio_length > d_maxsize) {
305 				/*
306 				 * XXX: If we have a stripesize we should really
307 				 * use it here. Care should be taken in the delete
308 				 * case if this is done as deletes can be very
309 				 * sensitive to size given how they are processed.
310 				 */
311 				bp2->bio_length = d_maxsize;
312 				if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
313 					bp2->bio_ma_n = howmany(
314 					    bp2->bio_ma_offset +
315 					    bp2->bio_length, PAGE_SIZE);
316 				}
317 				off += d_maxsize;
318 				/*
319 				 * To avoid a race, we need to grab the next bio
320 				 * before we schedule this one.  See "notes".
321 				 */
322 				bp3 = g_clone_bio(bp);
323 				if (bp3 == NULL)
324 					bp->bio_error = ENOMEM;
325 			}
326 			bp2->bio_done = g_disk_done;
327 			bp2->bio_pblkno = bp2->bio_offset / dp->d_sectorsize;
328 			bp2->bio_bcount = bp2->bio_length;
329 			bp2->bio_disk = dp;
330 			mtx_lock(&sc->start_mtx);
331 			devstat_start_transaction_bio(dp->d_devstat, bp2);
332 			mtx_unlock(&sc->start_mtx);
333 			dp->d_strategy(bp2);
334 			bp2 = bp3;
335 			bp3 = NULL;
336 		} while (bp2 != NULL);
337 		break;
338 	case BIO_GETATTR:
339 		/* Give the driver a chance to override */
340 		if (dp->d_getattr != NULL) {
341 			if (bp->bio_disk == NULL)
342 				bp->bio_disk = dp;
343 			error = dp->d_getattr(bp);
344 			if (error != -1)
345 				break;
346 			error = EJUSTRETURN;
347 		}
348 		if (g_handleattr_int(bp, "GEOM::candelete",
349 		    (dp->d_flags & DISKFLAG_CANDELETE) != 0))
350 			break;
351 		else if (g_handleattr_int(bp, "GEOM::fwsectors",
352 		    dp->d_fwsectors))
353 			break;
354 		else if (g_handleattr_int(bp, "GEOM::fwheads", dp->d_fwheads))
355 			break;
356 		else if (g_handleattr_off_t(bp, "GEOM::frontstuff", 0))
357 			break;
358 		else if (g_handleattr_str(bp, "GEOM::ident", dp->d_ident))
359 			break;
360 		else if (g_handleattr_uint16_t(bp, "GEOM::hba_vendor",
361 		    dp->d_hba_vendor))
362 			break;
363 		else if (g_handleattr_uint16_t(bp, "GEOM::hba_device",
364 		    dp->d_hba_device))
365 			break;
366 		else if (g_handleattr_uint16_t(bp, "GEOM::hba_subvendor",
367 		    dp->d_hba_subvendor))
368 			break;
369 		else if (g_handleattr_uint16_t(bp, "GEOM::hba_subdevice",
370 		    dp->d_hba_subdevice))
371 			break;
372 		else if (!strcmp(bp->bio_attribute, "GEOM::kerneldump"))
373 			g_disk_kerneldump(bp, dp);
374 		else if (!strcmp(bp->bio_attribute, "GEOM::setstate"))
375 			g_disk_setstate(bp, sc);
376 		else if (g_handleattr_uint16_t(bp, "GEOM::rotation_rate",
377 		    dp->d_rotation_rate))
378 			break;
379 		else
380 			error = ENOIOCTL;
381 		break;
382 	case BIO_FLUSH:
383 		g_trace(G_T_BIO, "g_disk_flushcache(%s)",
384 		    bp->bio_to->name);
385 		if (!(dp->d_flags & DISKFLAG_CANFLUSHCACHE)) {
386 			error = EOPNOTSUPP;
387 			break;
388 		}
389 		bp2 = g_clone_bio(bp);
390 		if (bp2 == NULL) {
391 			g_io_deliver(bp, ENOMEM);
392 			return;
393 		}
394 		bp2->bio_done = g_disk_done;
395 		bp2->bio_disk = dp;
396 		mtx_lock(&sc->start_mtx);
397 		devstat_start_transaction_bio(dp->d_devstat, bp2);
398 		mtx_unlock(&sc->start_mtx);
399 		dp->d_strategy(bp2);
400 		break;
401 	default:
402 		error = EOPNOTSUPP;
403 		break;
404 	}
405 	if (error != EJUSTRETURN)
406 		g_io_deliver(bp, error);
407 	return;
408 }
409 
410 static void
411 g_disk_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
412 {
413 	struct bio *bp;
414 	struct disk *dp;
415 	struct g_disk_softc *sc;
416 	char *buf;
417 	int res = 0;
418 
419 	sc = gp->softc;
420 	if (sc == NULL || (dp = sc->dp) == NULL)
421 		return;
422 	if (indent == NULL) {
423 		sbuf_printf(sb, " hd %u", dp->d_fwheads);
424 		sbuf_printf(sb, " sc %u", dp->d_fwsectors);
425 		return;
426 	}
427 	if (pp != NULL) {
428 		sbuf_printf(sb, "%s<fwheads>%u</fwheads>\n",
429 		    indent, dp->d_fwheads);
430 		sbuf_printf(sb, "%s<fwsectors>%u</fwsectors>\n",
431 		    indent, dp->d_fwsectors);
432 		if (dp->d_getattr != NULL) {
433 			buf = g_malloc(DISK_IDENT_SIZE, M_WAITOK);
434 			bp = g_alloc_bio();
435 			bp->bio_disk = dp;
436 			bp->bio_attribute = "GEOM::ident";
437 			bp->bio_length = DISK_IDENT_SIZE;
438 			bp->bio_data = buf;
439 			res = dp->d_getattr(bp);
440 			sbuf_printf(sb, "%s<ident>", indent);
441 			g_conf_printf_escaped(sb, "%s",
442 			    res == 0 ? buf: dp->d_ident);
443 			sbuf_printf(sb, "</ident>\n");
444 			bp->bio_attribute = "GEOM::lunid";
445 			bp->bio_length = DISK_IDENT_SIZE;
446 			bp->bio_data = buf;
447 			if (dp->d_getattr(bp) == 0) {
448 				sbuf_printf(sb, "%s<lunid>", indent);
449 				g_conf_printf_escaped(sb, "%s", buf);
450 				sbuf_printf(sb, "</lunid>\n");
451 			}
452 			bp->bio_attribute = "GEOM::lunname";
453 			bp->bio_length = DISK_IDENT_SIZE;
454 			bp->bio_data = buf;
455 			if (dp->d_getattr(bp) == 0) {
456 				sbuf_printf(sb, "%s<lunname>", indent);
457 				g_conf_printf_escaped(sb, "%s", buf);
458 				sbuf_printf(sb, "</lunname>\n");
459 			}
460 			g_destroy_bio(bp);
461 			g_free(buf);
462 		} else {
463 			sbuf_printf(sb, "%s<ident>", indent);
464 			g_conf_printf_escaped(sb, "%s", dp->d_ident);
465 			sbuf_printf(sb, "</ident>\n");
466 		}
467 		sbuf_printf(sb, "%s<descr>", indent);
468 		g_conf_printf_escaped(sb, "%s", dp->d_descr);
469 		sbuf_printf(sb, "</descr>\n");
470 	}
471 }
472 
473 static void
474 g_disk_resize(void *ptr, int flag)
475 {
476 	struct disk *dp;
477 	struct g_geom *gp;
478 	struct g_provider *pp;
479 
480 	if (flag == EV_CANCEL)
481 		return;
482 	g_topology_assert();
483 
484 	dp = ptr;
485 	gp = dp->d_geom;
486 
487 	if (dp->d_destroyed || gp == NULL)
488 		return;
489 
490 	LIST_FOREACH(pp, &gp->provider, provider) {
491 		if (pp->sectorsize != 0 &&
492 		    pp->sectorsize != dp->d_sectorsize)
493 			g_wither_provider(pp, ENXIO);
494 		else
495 			g_resize_provider(pp, dp->d_mediasize);
496 	}
497 }
498 
499 static void
500 g_disk_create(void *arg, int flag)
501 {
502 	struct g_geom *gp;
503 	struct g_provider *pp;
504 	struct disk *dp;
505 	struct g_disk_softc *sc;
506 	char tmpstr[80];
507 
508 	if (flag == EV_CANCEL)
509 		return;
510 	g_topology_assert();
511 	dp = arg;
512 	sc = g_malloc(sizeof(*sc), M_WAITOK | M_ZERO);
513 	mtx_init(&sc->start_mtx, "g_disk_start", NULL, MTX_DEF);
514 	mtx_init(&sc->done_mtx, "g_disk_done", NULL, MTX_DEF);
515 	sc->dp = dp;
516 	gp = g_new_geomf(&g_disk_class, "%s%d", dp->d_name, dp->d_unit);
517 	gp->softc = sc;
518 	pp = g_new_providerf(gp, "%s", gp->name);
519 	devstat_remove_entry(pp->stat);
520 	pp->stat = NULL;
521 	dp->d_devstat->id = pp;
522 	pp->mediasize = dp->d_mediasize;
523 	pp->sectorsize = dp->d_sectorsize;
524 	pp->stripeoffset = dp->d_stripeoffset;
525 	pp->stripesize = dp->d_stripesize;
526 	if ((dp->d_flags & DISKFLAG_UNMAPPED_BIO) != 0)
527 		pp->flags |= G_PF_ACCEPT_UNMAPPED;
528 	if ((dp->d_flags & DISKFLAG_DIRECT_COMPLETION) != 0)
529 		pp->flags |= G_PF_DIRECT_SEND;
530 	pp->flags |= G_PF_DIRECT_RECEIVE;
531 	if (bootverbose)
532 		printf("GEOM: new disk %s\n", gp->name);
533 	sysctl_ctx_init(&sc->sysctl_ctx);
534 	snprintf(tmpstr, sizeof(tmpstr), "GEOM disk %s", gp->name);
535 	sc->sysctl_tree = SYSCTL_ADD_NODE(&sc->sysctl_ctx,
536 		SYSCTL_STATIC_CHILDREN(_kern_geom_disk), OID_AUTO, gp->name,
537 		CTLFLAG_RD, 0, tmpstr);
538 	if (sc->sysctl_tree != NULL) {
539 		SYSCTL_ADD_STRING(&sc->sysctl_ctx,
540 		    SYSCTL_CHILDREN(sc->sysctl_tree), OID_AUTO, "led",
541 		    CTLFLAG_RWTUN, sc->led, sizeof(sc->led),
542 		    "LED name");
543 	}
544 	pp->private = sc;
545 	dp->d_geom = gp;
546 	g_error_provider(pp, 0);
547 }
548 
549 /*
550  * We get this callback after all of the consumers have gone away, and just
551  * before the provider is freed.  If the disk driver provided a d_gone
552  * callback, let them know that it is okay to free resources -- they won't
553  * be getting any more accesses from GEOM.
554  */
555 static void
556 g_disk_providergone(struct g_provider *pp)
557 {
558 	struct disk *dp;
559 	struct g_disk_softc *sc;
560 
561 	sc = (struct g_disk_softc *)pp->private;
562 	dp = sc->dp;
563 	if (dp != NULL && dp->d_gone != NULL)
564 		dp->d_gone(dp);
565 	if (sc->sysctl_tree != NULL) {
566 		sysctl_ctx_free(&sc->sysctl_ctx);
567 		sc->sysctl_tree = NULL;
568 	}
569 	if (sc->led[0] != 0) {
570 		led_set(sc->led, "0");
571 		sc->led[0] = 0;
572 	}
573 	pp->private = NULL;
574 	pp->geom->softc = NULL;
575 	mtx_destroy(&sc->done_mtx);
576 	mtx_destroy(&sc->start_mtx);
577 	g_free(sc);
578 }
579 
580 static void
581 g_disk_destroy(void *ptr, int flag)
582 {
583 	struct disk *dp;
584 	struct g_geom *gp;
585 	struct g_disk_softc *sc;
586 
587 	g_topology_assert();
588 	dp = ptr;
589 	gp = dp->d_geom;
590 	if (gp != NULL) {
591 		sc = gp->softc;
592 		if (sc != NULL)
593 			sc->dp = NULL;
594 		dp->d_geom = NULL;
595 		g_wither_geom(gp, ENXIO);
596 	}
597 	g_free(dp);
598 }
599 
600 /*
601  * We only allow printable characters in disk ident,
602  * the rest is converted to 'x<HH>'.
603  */
604 static void
605 g_disk_ident_adjust(char *ident, size_t size)
606 {
607 	char *p, tmp[4], newid[DISK_IDENT_SIZE];
608 
609 	newid[0] = '\0';
610 	for (p = ident; *p != '\0'; p++) {
611 		if (isprint(*p)) {
612 			tmp[0] = *p;
613 			tmp[1] = '\0';
614 		} else {
615 			snprintf(tmp, sizeof(tmp), "x%02hhx",
616 			    *(unsigned char *)p);
617 		}
618 		if (strlcat(newid, tmp, sizeof(newid)) >= sizeof(newid))
619 			break;
620 	}
621 	bzero(ident, size);
622 	strlcpy(ident, newid, size);
623 }
624 
625 struct disk *
626 disk_alloc(void)
627 {
628 
629 	return (g_malloc(sizeof(struct disk), M_WAITOK | M_ZERO));
630 }
631 
632 void
633 disk_create(struct disk *dp, int version)
634 {
635 
636 	if (version != DISK_VERSION) {
637 		printf("WARNING: Attempt to add disk %s%d %s",
638 		    dp->d_name, dp->d_unit,
639 		    " using incompatible ABI version of disk(9)\n");
640 		printf("WARNING: Ignoring disk %s%d\n",
641 		    dp->d_name, dp->d_unit);
642 		return;
643 	}
644 	if (dp->d_flags & DISKFLAG_RESERVED) {
645 		printf("WARNING: Attempt to add non-MPSAFE disk %s%d\n",
646 		    dp->d_name, dp->d_unit);
647 		printf("WARNING: Ignoring disk %s%d\n",
648 		    dp->d_name, dp->d_unit);
649 		return;
650 	}
651 	KASSERT(dp->d_strategy != NULL, ("disk_create need d_strategy"));
652 	KASSERT(dp->d_name != NULL, ("disk_create need d_name"));
653 	KASSERT(*dp->d_name != 0, ("disk_create need d_name"));
654 	KASSERT(strlen(dp->d_name) < SPECNAMELEN - 4, ("disk name too long"));
655 	if (dp->d_devstat == NULL)
656 		dp->d_devstat = devstat_new_entry(dp->d_name, dp->d_unit,
657 		    dp->d_sectorsize, DEVSTAT_ALL_SUPPORTED,
658 		    DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
659 	dp->d_geom = NULL;
660 	g_disk_ident_adjust(dp->d_ident, sizeof(dp->d_ident));
661 	g_post_event(g_disk_create, dp, M_WAITOK, dp, NULL);
662 }
663 
664 void
665 disk_destroy(struct disk *dp)
666 {
667 
668 	g_cancel_event(dp);
669 	dp->d_destroyed = 1;
670 	if (dp->d_devstat != NULL)
671 		devstat_remove_entry(dp->d_devstat);
672 	g_post_event(g_disk_destroy, dp, M_WAITOK, NULL);
673 }
674 
675 void
676 disk_gone(struct disk *dp)
677 {
678 	struct g_geom *gp;
679 	struct g_provider *pp;
680 
681 	gp = dp->d_geom;
682 	if (gp != NULL) {
683 		pp = LIST_FIRST(&gp->provider);
684 		if (pp != NULL) {
685 			KASSERT(LIST_NEXT(pp, provider) == NULL,
686 			    ("geom %p has more than one provider", gp));
687 			g_wither_provider(pp, ENXIO);
688 		}
689 	}
690 }
691 
692 void
693 disk_attr_changed(struct disk *dp, const char *attr, int flag)
694 {
695 	struct g_geom *gp;
696 	struct g_provider *pp;
697 
698 	gp = dp->d_geom;
699 	if (gp != NULL)
700 		LIST_FOREACH(pp, &gp->provider, provider)
701 			(void)g_attr_changed(pp, attr, flag);
702 }
703 
704 void
705 disk_media_changed(struct disk *dp, int flag)
706 {
707 	struct g_geom *gp;
708 	struct g_provider *pp;
709 
710 	gp = dp->d_geom;
711 	if (gp != NULL) {
712 		pp = LIST_FIRST(&gp->provider);
713 		if (pp != NULL) {
714 			KASSERT(LIST_NEXT(pp, provider) == NULL,
715 			    ("geom %p has more than one provider", gp));
716 			g_media_changed(pp, flag);
717 		}
718 	}
719 }
720 
721 void
722 disk_media_gone(struct disk *dp, int flag)
723 {
724 	struct g_geom *gp;
725 	struct g_provider *pp;
726 
727 	gp = dp->d_geom;
728 	if (gp != NULL) {
729 		pp = LIST_FIRST(&gp->provider);
730 		if (pp != NULL) {
731 			KASSERT(LIST_NEXT(pp, provider) == NULL,
732 			    ("geom %p has more than one provider", gp));
733 			g_media_gone(pp, flag);
734 		}
735 	}
736 }
737 
738 int
739 disk_resize(struct disk *dp, int flag)
740 {
741 
742 	if (dp->d_destroyed || dp->d_geom == NULL)
743 		return (0);
744 
745 	return (g_post_event(g_disk_resize, dp, flag, NULL));
746 }
747 
748 static void
749 g_kern_disks(void *p, int flag __unused)
750 {
751 	struct sbuf *sb;
752 	struct g_geom *gp;
753 	char *sp;
754 
755 	sb = p;
756 	sp = "";
757 	g_topology_assert();
758 	LIST_FOREACH(gp, &g_disk_class.geom, geom) {
759 		sbuf_printf(sb, "%s%s", sp, gp->name);
760 		sp = " ";
761 	}
762 	sbuf_finish(sb);
763 }
764 
765 static int
766 sysctl_disks(SYSCTL_HANDLER_ARGS)
767 {
768 	int error;
769 	struct sbuf *sb;
770 
771 	sb = sbuf_new_auto();
772 	g_waitfor_event(g_kern_disks, sb, M_WAITOK, NULL);
773 	error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
774 	sbuf_delete(sb);
775 	return error;
776 }
777 
778 SYSCTL_PROC(_kern, OID_AUTO, disks,
779     CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
780     sysctl_disks, "A", "names of available disks");
781