xref: /freebsd/sys/geom/geom_disk.c (revision 7d99ab9fd0cc2c1ce2ecef0ed6d0672c2a50b0cb)
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/sysctl.h>
51 #include <sys/devicestat.h>
52 #include <machine/md_var.h>
53 
54 #include <sys/lock.h>
55 #include <sys/mutex.h>
56 #include <geom/geom.h>
57 #include <geom/geom_disk.h>
58 #include <geom/geom_int.h>
59 
60 #include <dev/led/led.h>
61 
62 struct g_disk_softc {
63 	struct mtx		 done_mtx;
64 	struct disk		*dp;
65 	struct sysctl_ctx_list	sysctl_ctx;
66 	struct sysctl_oid	*sysctl_tree;
67 	char			led[64];
68 	uint32_t		state;
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 void __inline
94 g_disk_lock_giant(struct disk *dp)
95 {
96 
97 	if (dp->d_flags & DISKFLAG_NEEDSGIANT)
98 		mtx_lock(&Giant);
99 }
100 
101 static void __inline
102 g_disk_unlock_giant(struct disk *dp)
103 {
104 
105 	if (dp->d_flags & DISKFLAG_NEEDSGIANT)
106 		mtx_unlock(&Giant);
107 }
108 
109 static int
110 g_disk_access(struct g_provider *pp, int r, int w, int e)
111 {
112 	struct disk *dp;
113 	struct g_disk_softc *sc;
114 	int error;
115 
116 	g_trace(G_T_ACCESS, "g_disk_access(%s, %d, %d, %d)",
117 	    pp->name, r, w, e);
118 	g_topology_assert();
119 	sc = pp->private;
120 	if (sc == NULL || (dp = sc->dp) == NULL || dp->d_destroyed) {
121 		/*
122 		 * Allow decreasing access count even if disk is not
123 		 * avaliable anymore.
124 		 */
125 		if (r <= 0 && w <= 0 && e <= 0)
126 			return (0);
127 		return (ENXIO);
128 	}
129 	r += pp->acr;
130 	w += pp->acw;
131 	e += pp->ace;
132 	error = 0;
133 	if ((pp->acr + pp->acw + pp->ace) == 0 && (r + w + e) > 0) {
134 		if (dp->d_open != NULL) {
135 			g_disk_lock_giant(dp);
136 			error = dp->d_open(dp);
137 			if (bootverbose && error != 0)
138 				printf("Opened disk %s -> %d\n",
139 				    pp->name, error);
140 			g_disk_unlock_giant(dp);
141 			if (error != 0)
142 				return (error);
143 		}
144 		pp->mediasize = dp->d_mediasize;
145 		pp->sectorsize = dp->d_sectorsize;
146 		if (dp->d_maxsize == 0) {
147 			printf("WARNING: Disk drive %s%d has no d_maxsize\n",
148 			    dp->d_name, dp->d_unit);
149 			dp->d_maxsize = DFLTPHYS;
150 		}
151 		if (dp->d_flags & DISKFLAG_CANDELETE) {
152 			if (bootverbose && dp->d_delmaxsize == 0) {
153 				printf("WARNING: Disk drive %s%d has no d_delmaxsize\n",
154 				    dp->d_name, dp->d_unit);
155 				dp->d_delmaxsize = dp->d_maxsize;
156 			}
157 		} else {
158 			dp->d_delmaxsize = 0;
159 		}
160 		pp->stripeoffset = dp->d_stripeoffset;
161 		pp->stripesize = dp->d_stripesize;
162 		dp->d_flags |= DISKFLAG_OPEN;
163 	} else if ((pp->acr + pp->acw + pp->ace) > 0 && (r + w + e) == 0) {
164 		if (dp->d_close != NULL) {
165 			g_disk_lock_giant(dp);
166 			error = dp->d_close(dp);
167 			if (error != 0)
168 				printf("Closed disk %s -> %d\n",
169 				    pp->name, error);
170 			g_disk_unlock_giant(dp);
171 		}
172 		sc->state = G_STATE_ACTIVE;
173 		if (sc->led[0] != 0)
174 			led_set(sc->led, "0");
175 		dp->d_flags &= ~DISKFLAG_OPEN;
176 	}
177 	return (error);
178 }
179 
180 static void
181 g_disk_kerneldump(struct bio *bp, struct disk *dp)
182 {
183 	struct g_kerneldump *gkd;
184 	struct g_geom *gp;
185 
186 	gkd = (struct g_kerneldump*)bp->bio_data;
187 	gp = bp->bio_to->geom;
188 	g_trace(G_T_TOPOLOGY, "g_disk_kernedump(%s, %jd, %jd)",
189 		gp->name, (intmax_t)gkd->offset, (intmax_t)gkd->length);
190 	if (dp->d_dump == NULL) {
191 		g_io_deliver(bp, ENODEV);
192 		return;
193 	}
194 	gkd->di.dumper = dp->d_dump;
195 	gkd->di.priv = dp;
196 	gkd->di.blocksize = dp->d_sectorsize;
197 	gkd->di.maxiosize = dp->d_maxsize;
198 	gkd->di.mediaoffset = gkd->offset;
199 	if ((gkd->offset + gkd->length) > dp->d_mediasize)
200 		gkd->length = dp->d_mediasize - gkd->offset;
201 	gkd->di.mediasize = gkd->length;
202 	g_io_deliver(bp, 0);
203 }
204 
205 static void
206 g_disk_setstate(struct bio *bp, struct g_disk_softc *sc)
207 {
208 	const char *cmd;
209 
210 	memcpy(&sc->state, bp->bio_data, sizeof(sc->state));
211 	if (sc->led[0] != 0) {
212 		switch (sc->state) {
213 		case G_STATE_FAILED:
214 			cmd = "1";
215 			break;
216 		case G_STATE_REBUILD:
217 			cmd = "f5";
218 			break;
219 		case G_STATE_RESYNC:
220 			cmd = "f1";
221 			break;
222 		default:
223 			cmd = "0";
224 			break;
225 		}
226 		led_set(sc->led, cmd);
227 	}
228 	g_io_deliver(bp, 0);
229 }
230 
231 static void
232 g_disk_done(struct bio *bp)
233 {
234 	struct bio *bp2;
235 	struct g_disk_softc *sc;
236 
237 	/* See "notes" for why we need a mutex here */
238 	/* XXX: will witness accept a mix of Giant/unGiant drivers here ? */
239 	bp2 = bp->bio_parent;
240 	sc = bp2->bio_to->private;
241 	bp->bio_completed = bp->bio_length - bp->bio_resid;
242 	mtx_lock(&sc->done_mtx);
243 	if (bp2->bio_error == 0)
244 		bp2->bio_error = bp->bio_error;
245 	bp2->bio_completed += bp->bio_completed;
246 	if ((bp->bio_cmd & (BIO_READ|BIO_WRITE|BIO_DELETE)) != 0)
247 		devstat_end_transaction_bio(sc->dp->d_devstat, bp);
248 	g_destroy_bio(bp);
249 	bp2->bio_inbed++;
250 	if (bp2->bio_children == bp2->bio_inbed) {
251 		bp2->bio_resid = bp2->bio_bcount - bp2->bio_completed;
252 		g_io_deliver(bp2, bp2->bio_error);
253 	}
254 	mtx_unlock(&sc->done_mtx);
255 }
256 
257 static int
258 g_disk_ioctl(struct g_provider *pp, u_long cmd, void * data, int fflag, struct thread *td)
259 {
260 	struct disk *dp;
261 	struct g_disk_softc *sc;
262 	int error;
263 
264 	sc = pp->private;
265 	dp = sc->dp;
266 
267 	if (dp->d_ioctl == NULL)
268 		return (ENOIOCTL);
269 	g_disk_lock_giant(dp);
270 	error = dp->d_ioctl(dp, cmd, data, fflag, td);
271 	g_disk_unlock_giant(dp);
272 	return (error);
273 }
274 
275 static void
276 g_disk_start(struct bio *bp)
277 {
278 	struct bio *bp2, *bp3;
279 	struct disk *dp;
280 	struct g_disk_softc *sc;
281 	int error;
282 	off_t off;
283 
284 	sc = bp->bio_to->private;
285 	if (sc == NULL || (dp = sc->dp) == NULL || dp->d_destroyed) {
286 		g_io_deliver(bp, ENXIO);
287 		return;
288 	}
289 	error = EJUSTRETURN;
290 	switch(bp->bio_cmd) {
291 	case BIO_DELETE:
292 		if (!(dp->d_flags & DISKFLAG_CANDELETE)) {
293 			error = EOPNOTSUPP;
294 			break;
295 		}
296 		/* fall-through */
297 	case BIO_READ:
298 	case BIO_WRITE:
299 		off = 0;
300 		bp3 = NULL;
301 		bp2 = g_clone_bio(bp);
302 		if (bp2 == NULL) {
303 			error = ENOMEM;
304 			break;
305 		}
306 		do {
307 			off_t d_maxsize;
308 
309 			d_maxsize = (bp->bio_cmd == BIO_DELETE) ?
310 			    dp->d_delmaxsize : dp->d_maxsize;
311 			bp2->bio_offset += off;
312 			bp2->bio_length -= off;
313 			if ((bp->bio_flags & BIO_UNMAPPED) == 0) {
314 				bp2->bio_data += off;
315 			} else {
316 				KASSERT((dp->d_flags & DISKFLAG_UNMAPPED_BIO)
317 				    != 0,
318 				    ("unmapped bio not supported by disk %s",
319 				    dp->d_name));
320 				bp2->bio_ma += off / PAGE_SIZE;
321 				bp2->bio_ma_offset += off;
322 				bp2->bio_ma_offset %= PAGE_SIZE;
323 				bp2->bio_ma_n -= off / PAGE_SIZE;
324 			}
325 			if (bp2->bio_length > d_maxsize) {
326 				/*
327 				 * XXX: If we have a stripesize we should really
328 				 * use it here. Care should be taken in the delete
329 				 * case if this is done as deletes can be very
330 				 * sensitive to size given how they are processed.
331 				 */
332 				bp2->bio_length = d_maxsize;
333 				if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
334 					bp2->bio_ma_n = howmany(
335 					    bp2->bio_ma_offset +
336 					    bp2->bio_length, PAGE_SIZE);
337 				}
338 				off += d_maxsize;
339 				/*
340 				 * To avoid a race, we need to grab the next bio
341 				 * before we schedule this one.  See "notes".
342 				 */
343 				bp3 = g_clone_bio(bp);
344 				if (bp3 == NULL)
345 					bp->bio_error = ENOMEM;
346 			}
347 			bp2->bio_done = g_disk_done;
348 			bp2->bio_pblkno = bp2->bio_offset / dp->d_sectorsize;
349 			bp2->bio_bcount = bp2->bio_length;
350 			bp2->bio_disk = dp;
351 			devstat_start_transaction_bio(dp->d_devstat, bp2);
352 			g_disk_lock_giant(dp);
353 			dp->d_strategy(bp2);
354 			g_disk_unlock_giant(dp);
355 			bp2 = bp3;
356 			bp3 = NULL;
357 		} while (bp2 != NULL);
358 		break;
359 	case BIO_GETATTR:
360 		/* Give the driver a chance to override */
361 		if (dp->d_getattr != NULL) {
362 			if (bp->bio_disk == NULL)
363 				bp->bio_disk = dp;
364 			error = dp->d_getattr(bp);
365 			if (error != -1)
366 				break;
367 			error = EJUSTRETURN;
368 		}
369 		if (g_handleattr_int(bp, "GEOM::candelete",
370 		    (dp->d_flags & DISKFLAG_CANDELETE) != 0))
371 			break;
372 		else if (g_handleattr_int(bp, "GEOM::fwsectors",
373 		    dp->d_fwsectors))
374 			break;
375 		else if (g_handleattr_int(bp, "GEOM::fwheads", dp->d_fwheads))
376 			break;
377 		else if (g_handleattr_off_t(bp, "GEOM::frontstuff", 0))
378 			break;
379 		else if (g_handleattr_str(bp, "GEOM::ident", dp->d_ident))
380 			break;
381 		else if (g_handleattr(bp, "GEOM::hba_vendor",
382 		    &dp->d_hba_vendor, 2))
383 			break;
384 		else if (g_handleattr(bp, "GEOM::hba_device",
385 		    &dp->d_hba_device, 2))
386 			break;
387 		else if (g_handleattr(bp, "GEOM::hba_subvendor",
388 		    &dp->d_hba_subvendor, 2))
389 			break;
390 		else if (g_handleattr(bp, "GEOM::hba_subdevice",
391 		    &dp->d_hba_subdevice, 2))
392 			break;
393 		else if (!strcmp(bp->bio_attribute, "GEOM::kerneldump"))
394 			g_disk_kerneldump(bp, dp);
395 		else if (!strcmp(bp->bio_attribute, "GEOM::setstate"))
396 			g_disk_setstate(bp, sc);
397 		else
398 			error = ENOIOCTL;
399 		break;
400 	case BIO_FLUSH:
401 		g_trace(G_T_BIO, "g_disk_flushcache(%s)",
402 		    bp->bio_to->name);
403 		if (!(dp->d_flags & DISKFLAG_CANFLUSHCACHE)) {
404 			error = EOPNOTSUPP;
405 			break;
406 		}
407 		bp2 = g_clone_bio(bp);
408 		if (bp2 == NULL) {
409 			g_io_deliver(bp, ENOMEM);
410 			return;
411 		}
412 		bp2->bio_done = g_disk_done;
413 		bp2->bio_disk = dp;
414 		g_disk_lock_giant(dp);
415 		dp->d_strategy(bp2);
416 		g_disk_unlock_giant(dp);
417 		break;
418 	default:
419 		error = EOPNOTSUPP;
420 		break;
421 	}
422 	if (error != EJUSTRETURN)
423 		g_io_deliver(bp, error);
424 	return;
425 }
426 
427 static void
428 g_disk_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
429 {
430 	struct bio *bp;
431 	struct disk *dp;
432 	struct g_disk_softc *sc;
433 	char *buf;
434 	int res = 0;
435 
436 	sc = gp->softc;
437 	if (sc == NULL || (dp = sc->dp) == NULL)
438 		return;
439 	if (indent == NULL) {
440 		sbuf_printf(sb, " hd %u", dp->d_fwheads);
441 		sbuf_printf(sb, " sc %u", dp->d_fwsectors);
442 		return;
443 	}
444 	if (pp != NULL) {
445 		sbuf_printf(sb, "%s<fwheads>%u</fwheads>\n",
446 		    indent, dp->d_fwheads);
447 		sbuf_printf(sb, "%s<fwsectors>%u</fwsectors>\n",
448 		    indent, dp->d_fwsectors);
449 		if (dp->d_getattr != NULL) {
450 			buf = g_malloc(DISK_IDENT_SIZE, M_WAITOK);
451 			bp = g_alloc_bio();
452 			bp->bio_disk = dp;
453 			bp->bio_attribute = "GEOM::ident";
454 			bp->bio_length = DISK_IDENT_SIZE;
455 			bp->bio_data = buf;
456 			res = dp->d_getattr(bp);
457 			sbuf_printf(sb, "%s<ident>%s</ident>\n", indent,
458 			    res == 0 ? buf: dp->d_ident);
459 			bp->bio_attribute = "GEOM::lunid";
460 			bp->bio_length = DISK_IDENT_SIZE;
461 			bp->bio_data = buf;
462 			if (dp->d_getattr(bp) == 0)
463 				sbuf_printf(sb, "%s<lunid>%s</lunid>\n",
464 				    indent, buf);
465 			g_destroy_bio(bp);
466 			g_free(buf);
467 		} else
468 			sbuf_printf(sb, "%s<ident>%s</ident>\n", indent,
469 			    dp->d_ident);
470 		sbuf_printf(sb, "%s<descr>%s</descr>\n", indent, dp->d_descr);
471 	}
472 }
473 
474 static void
475 g_disk_resize(void *ptr, int flag)
476 {
477 	struct disk *dp;
478 	struct g_geom *gp;
479 	struct g_provider *pp;
480 
481 	if (flag == EV_CANCEL)
482 		return;
483 	g_topology_assert();
484 
485 	dp = ptr;
486 	gp = dp->d_geom;
487 
488 	if (dp->d_destroyed || gp == NULL)
489 		return;
490 
491 	LIST_FOREACH(pp, &gp->provider, provider) {
492 		if (pp->sectorsize != 0 &&
493 		    pp->sectorsize != dp->d_sectorsize)
494 			g_wither_provider(pp, ENXIO);
495 		else
496 			g_resize_provider(pp, dp->d_mediasize);
497 	}
498 }
499 
500 static void
501 g_disk_create(void *arg, int flag)
502 {
503 	struct g_geom *gp;
504 	struct g_provider *pp;
505 	struct disk *dp;
506 	struct g_disk_softc *sc;
507 	char tmpstr[80];
508 
509 	if (flag == EV_CANCEL)
510 		return;
511 	g_topology_assert();
512 	dp = arg;
513 	sc = g_malloc(sizeof(*sc), M_WAITOK | M_ZERO);
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 	pp->mediasize = dp->d_mediasize;
520 	pp->sectorsize = dp->d_sectorsize;
521 	pp->stripeoffset = dp->d_stripeoffset;
522 	pp->stripesize = dp->d_stripesize;
523 	if ((dp->d_flags & DISKFLAG_UNMAPPED_BIO) != 0)
524 		pp->flags |= G_PF_ACCEPT_UNMAPPED;
525 	if (bootverbose)
526 		printf("GEOM: new disk %s\n", gp->name);
527 	sysctl_ctx_init(&sc->sysctl_ctx);
528 	snprintf(tmpstr, sizeof(tmpstr), "GEOM disk %s", gp->name);
529 	sc->sysctl_tree = SYSCTL_ADD_NODE(&sc->sysctl_ctx,
530 		SYSCTL_STATIC_CHILDREN(_kern_geom_disk), OID_AUTO, gp->name,
531 		CTLFLAG_RD, 0, tmpstr);
532 	if (sc->sysctl_tree != NULL) {
533 		snprintf(tmpstr, sizeof(tmpstr),
534 		    "kern.geom.disk.%s.led", gp->name);
535 		TUNABLE_STR_FETCH(tmpstr, sc->led, sizeof(sc->led));
536 		SYSCTL_ADD_STRING(&sc->sysctl_ctx,
537 		    SYSCTL_CHILDREN(sc->sysctl_tree), OID_AUTO, "led",
538 		    CTLFLAG_RW | CTLFLAG_TUN, sc->led, sizeof(sc->led),
539 		    "LED name");
540 	}
541 	pp->private = sc;
542 	dp->d_geom = gp;
543 	g_error_provider(pp, 0);
544 }
545 
546 /*
547  * We get this callback after all of the consumers have gone away, and just
548  * before the provider is freed.  If the disk driver provided a d_gone
549  * callback, let them know that it is okay to free resources -- they won't
550  * be getting any more accesses from GEOM.
551  */
552 static void
553 g_disk_providergone(struct g_provider *pp)
554 {
555 	struct disk *dp;
556 	struct g_disk_softc *sc;
557 
558 	sc = (struct g_disk_softc *)pp->private;
559 	dp = sc->dp;
560 	if (dp != NULL && dp->d_gone != NULL)
561 		dp->d_gone(dp);
562 	if (sc->sysctl_tree != NULL) {
563 		sysctl_ctx_free(&sc->sysctl_ctx);
564 		sc->sysctl_tree = NULL;
565 	}
566 	if (sc->led[0] != 0) {
567 		led_set(sc->led, "0");
568 		sc->led[0] = 0;
569 	}
570 	pp->private = NULL;
571 	pp->geom->softc = NULL;
572 	mtx_destroy(&sc->done_mtx);
573 	g_free(sc);
574 }
575 
576 static void
577 g_disk_destroy(void *ptr, int flag)
578 {
579 	struct disk *dp;
580 	struct g_geom *gp;
581 	struct g_disk_softc *sc;
582 
583 	g_topology_assert();
584 	dp = ptr;
585 	gp = dp->d_geom;
586 	if (gp != NULL) {
587 		sc = gp->softc;
588 		if (sc != NULL)
589 			sc->dp = NULL;
590 		dp->d_geom = NULL;
591 		g_wither_geom(gp, ENXIO);
592 	}
593 	g_free(dp);
594 }
595 
596 /*
597  * We only allow printable characters in disk ident,
598  * the rest is converted to 'x<HH>'.
599  */
600 static void
601 g_disk_ident_adjust(char *ident, size_t size)
602 {
603 	char *p, tmp[4], newid[DISK_IDENT_SIZE];
604 
605 	newid[0] = '\0';
606 	for (p = ident; *p != '\0'; p++) {
607 		if (isprint(*p)) {
608 			tmp[0] = *p;
609 			tmp[1] = '\0';
610 		} else {
611 			snprintf(tmp, sizeof(tmp), "x%02hhx",
612 			    *(unsigned char *)p);
613 		}
614 		if (strlcat(newid, tmp, sizeof(newid)) >= sizeof(newid))
615 			break;
616 	}
617 	bzero(ident, size);
618 	strlcpy(ident, newid, size);
619 }
620 
621 struct disk *
622 disk_alloc(void)
623 {
624 
625 	return (g_malloc(sizeof(struct disk), M_WAITOK | M_ZERO));
626 }
627 
628 void
629 disk_create(struct disk *dp, int version)
630 {
631 
632 	if (version != DISK_VERSION_02) {
633 		printf("WARNING: Attempt to add disk %s%d %s",
634 		    dp->d_name, dp->d_unit,
635 		    " using incompatible ABI version of disk(9)\n");
636 		printf("WARNING: Ignoring disk %s%d\n",
637 		    dp->d_name, dp->d_unit);
638 		return;
639 	}
640 	KASSERT(dp->d_strategy != NULL, ("disk_create need d_strategy"));
641 	KASSERT(dp->d_name != NULL, ("disk_create need d_name"));
642 	KASSERT(*dp->d_name != 0, ("disk_create need d_name"));
643 	KASSERT(strlen(dp->d_name) < SPECNAMELEN - 4, ("disk name too long"));
644 	if (dp->d_devstat == NULL)
645 		dp->d_devstat = devstat_new_entry(dp->d_name, dp->d_unit,
646 		    dp->d_sectorsize, DEVSTAT_ALL_SUPPORTED,
647 		    DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
648 	dp->d_geom = NULL;
649 	g_disk_ident_adjust(dp->d_ident, sizeof(dp->d_ident));
650 	g_post_event(g_disk_create, dp, M_WAITOK, dp, NULL);
651 }
652 
653 void
654 disk_destroy(struct disk *dp)
655 {
656 
657 	g_cancel_event(dp);
658 	dp->d_destroyed = 1;
659 	if (dp->d_devstat != NULL)
660 		devstat_remove_entry(dp->d_devstat);
661 	g_post_event(g_disk_destroy, dp, M_WAITOK, NULL);
662 }
663 
664 void
665 disk_gone(struct disk *dp)
666 {
667 	struct g_geom *gp;
668 	struct g_provider *pp;
669 
670 	gp = dp->d_geom;
671 	if (gp != NULL) {
672 		pp = LIST_FIRST(&gp->provider);
673 		if (pp != NULL) {
674 			KASSERT(LIST_NEXT(pp, provider) == NULL,
675 			    ("geom %p has more than one provider", gp));
676 			g_wither_provider(pp, ENXIO);
677 		}
678 	}
679 }
680 
681 void
682 disk_attr_changed(struct disk *dp, const char *attr, int flag)
683 {
684 	struct g_geom *gp;
685 	struct g_provider *pp;
686 
687 	gp = dp->d_geom;
688 	if (gp != NULL)
689 		LIST_FOREACH(pp, &gp->provider, provider)
690 			(void)g_attr_changed(pp, attr, flag);
691 }
692 
693 void
694 disk_media_changed(struct disk *dp, int flag)
695 {
696 	struct g_geom *gp;
697 	struct g_provider *pp;
698 
699 	gp = dp->d_geom;
700 	if (gp != NULL) {
701 		pp = LIST_FIRST(&gp->provider);
702 		if (pp != NULL) {
703 			KASSERT(LIST_NEXT(pp, provider) == NULL,
704 			    ("geom %p has more than one provider", gp));
705 			g_media_changed(pp, flag);
706 		}
707 	}
708 }
709 
710 void
711 disk_media_gone(struct disk *dp, int flag)
712 {
713 	struct g_geom *gp;
714 	struct g_provider *pp;
715 
716 	gp = dp->d_geom;
717 	if (gp != NULL) {
718 		pp = LIST_FIRST(&gp->provider);
719 		if (pp != NULL) {
720 			KASSERT(LIST_NEXT(pp, provider) == NULL,
721 			    ("geom %p has more than one provider", gp));
722 			g_media_gone(pp, flag);
723 		}
724 	}
725 }
726 
727 int
728 disk_resize(struct disk *dp, int flag)
729 {
730 
731 	if (dp->d_destroyed || dp->d_geom == NULL)
732 		return (0);
733 
734 	return (g_post_event(g_disk_resize, dp, flag, NULL));
735 }
736 
737 static void
738 g_kern_disks(void *p, int flag __unused)
739 {
740 	struct sbuf *sb;
741 	struct g_geom *gp;
742 	char *sp;
743 
744 	sb = p;
745 	sp = "";
746 	g_topology_assert();
747 	LIST_FOREACH(gp, &g_disk_class.geom, geom) {
748 		sbuf_printf(sb, "%s%s", sp, gp->name);
749 		sp = " ";
750 	}
751 	sbuf_finish(sb);
752 }
753 
754 static int
755 sysctl_disks(SYSCTL_HANDLER_ARGS)
756 {
757 	int error;
758 	struct sbuf *sb;
759 
760 	sb = sbuf_new_auto();
761 	g_waitfor_event(g_kern_disks, sb, M_WAITOK, NULL);
762 	error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
763 	sbuf_delete(sb);
764 	return error;
765 }
766 
767 SYSCTL_PROC(_kern, OID_AUTO, disks,
768     CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
769     sysctl_disks, "A", "names of available disks");
770