xref: /freebsd/sys/geom/geom_disk.c (revision 024932aae96e5e4fe5d39827e4b4abdc4f1adc95)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2002 Poul-Henning Kamp
5  * Copyright (c) 2002 Networks Associates Technology, Inc.
6  * All rights reserved.
7  *
8  * This software was developed for the FreeBSD Project by Poul-Henning Kamp
9  * and NAI Labs, the Security Research Division of Network Associates, Inc.
10  * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
11  * DARPA CHATS research program.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. The names of the authors may not be used to endorse or promote
22  *    products derived from this software without specific prior written
23  *    permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  */
37 
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40 
41 #include "opt_geom.h"
42 
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/kernel.h>
46 #include <sys/sysctl.h>
47 #include <sys/bio.h>
48 #include <sys/bus.h>
49 #include <sys/ctype.h>
50 #include <sys/fcntl.h>
51 #include <sys/malloc.h>
52 #include <sys/sbuf.h>
53 #include <sys/devicestat.h>
54 #include <machine/md_var.h>
55 
56 #include <sys/lock.h>
57 #include <sys/mutex.h>
58 #include <geom/geom.h>
59 #include <geom/geom_disk.h>
60 #include <geom/geom_int.h>
61 
62 #include <dev/led/led.h>
63 
64 #include <machine/bus.h>
65 
66 struct g_disk_softc {
67 	struct disk		*dp;
68 	struct sysctl_ctx_list	sysctl_ctx;
69 	struct sysctl_oid	*sysctl_tree;
70 	char			led[64];
71 	uint32_t		state;
72 	struct mtx		 done_mtx;
73 };
74 
75 static g_access_t g_disk_access;
76 static g_start_t g_disk_start;
77 static g_ioctl_t g_disk_ioctl;
78 static g_dumpconf_t g_disk_dumpconf;
79 static g_provgone_t g_disk_providergone;
80 
81 static int g_disk_sysctl_flags(SYSCTL_HANDLER_ARGS);
82 
83 static struct g_class g_disk_class = {
84 	.name = G_DISK_CLASS_NAME,
85 	.version = G_VERSION,
86 	.start = g_disk_start,
87 	.access = g_disk_access,
88 	.ioctl = g_disk_ioctl,
89 	.providergone = g_disk_providergone,
90 	.dumpconf = g_disk_dumpconf,
91 };
92 
93 SYSCTL_DECL(_kern_geom);
94 static SYSCTL_NODE(_kern_geom, OID_AUTO, disk, CTLFLAG_RW, 0,
95     "GEOM_DISK stuff");
96 
97 DECLARE_GEOM_CLASS(g_disk_class, g_disk);
98 
99 static int
100 g_disk_access(struct g_provider *pp, int r, int w, int e)
101 {
102 	struct disk *dp;
103 	struct g_disk_softc *sc;
104 	int error;
105 
106 	g_trace(G_T_ACCESS, "g_disk_access(%s, %d, %d, %d)",
107 	    pp->name, r, w, e);
108 	g_topology_assert();
109 	sc = pp->private;
110 	if ((dp = sc->dp) == NULL || dp->d_destroyed) {
111 		/*
112 		 * Allow decreasing access count even if disk is not
113 		 * available anymore.
114 		 */
115 		if (r <= 0 && w <= 0 && e <= 0)
116 			return (0);
117 		return (ENXIO);
118 	}
119 	r += pp->acr;
120 	w += pp->acw;
121 	e += pp->ace;
122 	error = 0;
123 	if ((pp->acr + pp->acw + pp->ace) == 0 && (r + w + e) > 0) {
124 		/*
125 		 * It would be better to defer this decision to d_open if
126 		 * it was able to take flags.
127 		 */
128 		if (w > 0 && (dp->d_flags & DISKFLAG_WRITE_PROTECT) != 0)
129 			error = EROFS;
130 		if (error == 0 && dp->d_open != NULL)
131 			error = dp->d_open(dp);
132 		if (bootverbose && error != 0)
133 			printf("Opened disk %s -> %d\n", pp->name, error);
134 		if (error != 0)
135 			return (error);
136 		pp->sectorsize = dp->d_sectorsize;
137 		if (dp->d_maxsize == 0) {
138 			printf("WARNING: Disk drive %s%d has no d_maxsize\n",
139 			    dp->d_name, dp->d_unit);
140 			dp->d_maxsize = DFLTPHYS;
141 		}
142 		if (dp->d_delmaxsize == 0) {
143 			if (bootverbose && dp->d_flags & DISKFLAG_CANDELETE) {
144 				printf("WARNING: Disk drive %s%d has no "
145 				    "d_delmaxsize\n", dp->d_name, dp->d_unit);
146 			}
147 			dp->d_delmaxsize = dp->d_maxsize;
148 		}
149 		pp->stripeoffset = dp->d_stripeoffset;
150 		pp->stripesize = dp->d_stripesize;
151 		dp->d_flags |= DISKFLAG_OPEN;
152 		/*
153 		 * Do not invoke resize event when initial size was zero.
154 		 * Some disks report its size only after first opening.
155 		 */
156 		if (pp->mediasize == 0)
157 			pp->mediasize = dp->d_mediasize;
158 		else
159 			g_resize_provider(pp, dp->d_mediasize);
160 	} else if ((pp->acr + pp->acw + pp->ace) > 0 && (r + w + e) == 0) {
161 		if (dp->d_close != NULL) {
162 			error = dp->d_close(dp);
163 			if (error != 0)
164 				printf("Closed disk %s -> %d\n",
165 				    pp->name, error);
166 		}
167 		sc->state = G_STATE_ACTIVE;
168 		if (sc->led[0] != 0)
169 			led_set(sc->led, "0");
170 		dp->d_flags &= ~DISKFLAG_OPEN;
171 	}
172 	return (error);
173 }
174 
175 static void
176 g_disk_kerneldump(struct bio *bp, struct disk *dp)
177 {
178 	struct g_kerneldump *gkd;
179 	struct g_geom *gp;
180 
181 	gkd = (struct g_kerneldump*)bp->bio_data;
182 	gp = bp->bio_to->geom;
183 	g_trace(G_T_TOPOLOGY, "g_disk_kerneldump(%s, %jd, %jd)",
184 		gp->name, (intmax_t)gkd->offset, (intmax_t)gkd->length);
185 	if (dp->d_dump == NULL) {
186 		g_io_deliver(bp, ENODEV);
187 		return;
188 	}
189 	gkd->di.dumper = dp->d_dump;
190 	gkd->di.priv = dp;
191 	gkd->di.blocksize = dp->d_sectorsize;
192 	gkd->di.maxiosize = dp->d_maxsize;
193 	gkd->di.mediaoffset = gkd->offset;
194 	if ((gkd->offset + gkd->length) > dp->d_mediasize)
195 		gkd->length = dp->d_mediasize - gkd->offset;
196 	gkd->di.mediasize = gkd->length;
197 	g_io_deliver(bp, 0);
198 }
199 
200 static void
201 g_disk_setstate(struct bio *bp, struct g_disk_softc *sc)
202 {
203 	const char *cmd;
204 
205 	memcpy(&sc->state, bp->bio_data, sizeof(sc->state));
206 	if (sc->led[0] != 0) {
207 		switch (sc->state) {
208 		case G_STATE_FAILED:
209 			cmd = "1";
210 			break;
211 		case G_STATE_REBUILD:
212 			cmd = "f5";
213 			break;
214 		case G_STATE_RESYNC:
215 			cmd = "f1";
216 			break;
217 		default:
218 			cmd = "0";
219 			break;
220 		}
221 		led_set(sc->led, cmd);
222 	}
223 	g_io_deliver(bp, 0);
224 }
225 
226 static void
227 g_disk_done(struct bio *bp)
228 {
229 	struct bintime now;
230 	struct bio *bp2;
231 	struct g_disk_softc *sc;
232 
233 	/* See "notes" for why we need a mutex here */
234 	/* XXX: will witness accept a mix of Giant/unGiant drivers here ? */
235 	bp2 = bp->bio_parent;
236 	sc = bp2->bio_to->private;
237 	bp->bio_completed = bp->bio_length - bp->bio_resid;
238 	binuptime(&now);
239 	mtx_lock(&sc->done_mtx);
240 	if (bp2->bio_error == 0)
241 		bp2->bio_error = bp->bio_error;
242 	bp2->bio_completed += bp->bio_completed;
243 
244 	switch (bp->bio_cmd) {
245 	case BIO_ZONE:
246 		bcopy(&bp->bio_zone, &bp2->bio_zone, sizeof(bp->bio_zone));
247 		/*FALLTHROUGH*/
248 	case BIO_READ:
249 	case BIO_WRITE:
250 	case BIO_DELETE:
251 	case BIO_FLUSH:
252 		devstat_end_transaction_bio_bt(sc->dp->d_devstat, bp, &now);
253 		break;
254 	default:
255 		break;
256 	}
257 	bp2->bio_inbed++;
258 	if (bp2->bio_children == bp2->bio_inbed) {
259 		mtx_unlock(&sc->done_mtx);
260 		bp2->bio_resid = bp2->bio_bcount - bp2->bio_completed;
261 		g_io_deliver(bp2, bp2->bio_error);
262 	} else
263 		mtx_unlock(&sc->done_mtx);
264 	g_destroy_bio(bp);
265 }
266 
267 static int
268 g_disk_ioctl(struct g_provider *pp, u_long cmd, void * data, int fflag, struct thread *td)
269 {
270 	struct disk *dp;
271 	struct g_disk_softc *sc;
272 	int error;
273 
274 	sc = pp->private;
275 	dp = sc->dp;
276 	KASSERT(dp != NULL && !dp->d_destroyed,
277 	    ("g_disk_ioctl(%lx) on destroyed disk %s", cmd, pp->name));
278 
279 	if (dp->d_ioctl == NULL)
280 		return (ENOIOCTL);
281 	error = dp->d_ioctl(dp, cmd, data, fflag, td);
282 	return (error);
283 }
284 
285 static off_t
286 g_disk_maxsize(struct disk *dp, struct bio *bp)
287 {
288 	if (bp->bio_cmd == BIO_DELETE)
289 		return (dp->d_delmaxsize);
290 	return (dp->d_maxsize);
291 }
292 
293 static int
294 g_disk_maxsegs(struct disk *dp, struct bio *bp)
295 {
296 	return ((g_disk_maxsize(dp, bp) / PAGE_SIZE) + 1);
297 }
298 
299 static void
300 g_disk_advance(struct disk *dp, struct bio *bp, off_t off)
301 {
302 
303 	bp->bio_offset += off;
304 	bp->bio_length -= off;
305 
306 	if ((bp->bio_flags & BIO_VLIST) != 0) {
307 		bus_dma_segment_t *seg, *end;
308 
309 		seg = (bus_dma_segment_t *)bp->bio_data;
310 		end = (bus_dma_segment_t *)bp->bio_data + bp->bio_ma_n;
311 		off += bp->bio_ma_offset;
312 		while (off >= seg->ds_len) {
313 			KASSERT((seg != end),
314 			    ("vlist request runs off the end"));
315 			off -= seg->ds_len;
316 			seg++;
317 		}
318 		bp->bio_ma_offset = off;
319 		bp->bio_ma_n = end - seg;
320 		bp->bio_data = (void *)seg;
321 	} else if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
322 		bp->bio_ma += off / PAGE_SIZE;
323 		bp->bio_ma_offset += off;
324 		bp->bio_ma_offset %= PAGE_SIZE;
325 		bp->bio_ma_n -= off / PAGE_SIZE;
326 	} else {
327 		bp->bio_data += off;
328 	}
329 }
330 
331 static void
332 g_disk_seg_limit(bus_dma_segment_t *seg, off_t *poffset,
333     off_t *plength, int *ppages)
334 {
335 	uintptr_t seg_page_base;
336 	uintptr_t seg_page_end;
337 	off_t offset;
338 	off_t length;
339 	int seg_pages;
340 
341 	offset = *poffset;
342 	length = *plength;
343 
344 	if (length > seg->ds_len - offset)
345 		length = seg->ds_len - offset;
346 
347 	seg_page_base = trunc_page(seg->ds_addr + offset);
348 	seg_page_end  = round_page(seg->ds_addr + offset + length);
349 	seg_pages = (seg_page_end - seg_page_base) >> PAGE_SHIFT;
350 
351 	if (seg_pages > *ppages) {
352 		seg_pages = *ppages;
353 		length = (seg_page_base + (seg_pages << PAGE_SHIFT)) -
354 		    (seg->ds_addr + offset);
355 	}
356 
357 	*poffset = 0;
358 	*plength -= length;
359 	*ppages -= seg_pages;
360 }
361 
362 static off_t
363 g_disk_vlist_limit(struct disk *dp, struct bio *bp, bus_dma_segment_t **pendseg)
364 {
365 	bus_dma_segment_t *seg, *end;
366 	off_t residual;
367 	off_t offset;
368 	int pages;
369 
370 	seg = (bus_dma_segment_t *)bp->bio_data;
371 	end = (bus_dma_segment_t *)bp->bio_data + bp->bio_ma_n;
372 	residual = bp->bio_length;
373 	offset = bp->bio_ma_offset;
374 	pages = g_disk_maxsegs(dp, bp);
375 	while (residual != 0 && pages != 0) {
376 		KASSERT((seg != end),
377 		    ("vlist limit runs off the end"));
378 		g_disk_seg_limit(seg, &offset, &residual, &pages);
379 		seg++;
380 	}
381 	if (pendseg != NULL)
382 		*pendseg = seg;
383 	return (residual);
384 }
385 
386 static bool
387 g_disk_limit(struct disk *dp, struct bio *bp)
388 {
389 	bool limited = false;
390 	off_t maxsz;
391 
392 	maxsz = g_disk_maxsize(dp, bp);
393 
394 	/*
395 	 * XXX: If we have a stripesize we should really use it here.
396 	 *      Care should be taken in the delete case if this is done
397 	 *      as deletes can be very sensitive to size given how they
398 	 *      are processed.
399 	 */
400 	if (bp->bio_length > maxsz) {
401 		bp->bio_length = maxsz;
402 		limited = true;
403 	}
404 
405 	if ((bp->bio_flags & BIO_VLIST) != 0) {
406 		bus_dma_segment_t *firstseg, *endseg;
407 		off_t residual;
408 
409 		firstseg = (bus_dma_segment_t*)bp->bio_data;
410 		residual = g_disk_vlist_limit(dp, bp, &endseg);
411 		if (residual != 0) {
412 			bp->bio_ma_n = endseg - firstseg;
413 			bp->bio_length -= residual;
414 			limited = true;
415 		}
416 	} else if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
417 		bp->bio_ma_n =
418 		    howmany(bp->bio_ma_offset + bp->bio_length, PAGE_SIZE);
419 	}
420 
421 	return (limited);
422 }
423 
424 static void
425 g_disk_start(struct bio *bp)
426 {
427 	struct bio *bp2, *bp3;
428 	struct disk *dp;
429 	struct g_disk_softc *sc;
430 	int error;
431 	off_t off;
432 
433 	biotrack(bp, __func__);
434 
435 	sc = bp->bio_to->private;
436 	dp = sc->dp;
437 	KASSERT(dp != NULL && !dp->d_destroyed,
438 	    ("g_disk_start(%p) on destroyed disk %s", bp, bp->bio_to->name));
439 	error = EJUSTRETURN;
440 	switch(bp->bio_cmd) {
441 	case BIO_DELETE:
442 		if (!(dp->d_flags & DISKFLAG_CANDELETE)) {
443 			error = EOPNOTSUPP;
444 			break;
445 		}
446 		/* fall-through */
447 	case BIO_READ:
448 	case BIO_WRITE:
449 		KASSERT((dp->d_flags & DISKFLAG_UNMAPPED_BIO) != 0 ||
450 		    (bp->bio_flags & BIO_UNMAPPED) == 0,
451 		    ("unmapped bio not supported by disk %s", dp->d_name));
452 		off = 0;
453 		bp3 = NULL;
454 		bp2 = g_clone_bio(bp);
455 		if (bp2 == NULL) {
456 			error = ENOMEM;
457 			break;
458 		}
459 		for (;;) {
460 			if (g_disk_limit(dp, bp2)) {
461 				off += bp2->bio_length;
462 
463 				/*
464 				 * To avoid a race, we need to grab the next bio
465 				 * before we schedule this one.  See "notes".
466 				 */
467 				bp3 = g_clone_bio(bp);
468 				if (bp3 == NULL)
469 					bp->bio_error = ENOMEM;
470 			}
471 			bp2->bio_done = g_disk_done;
472 			bp2->bio_pblkno = bp2->bio_offset / dp->d_sectorsize;
473 			bp2->bio_bcount = bp2->bio_length;
474 			bp2->bio_disk = dp;
475 			devstat_start_transaction_bio(dp->d_devstat, bp2);
476 			dp->d_strategy(bp2);
477 
478 			if (bp3 == NULL)
479 				break;
480 
481 			bp2 = bp3;
482 			bp3 = NULL;
483 			g_disk_advance(dp, bp2, off);
484 		}
485 		break;
486 	case BIO_GETATTR:
487 		/* Give the driver a chance to override */
488 		if (dp->d_getattr != NULL) {
489 			if (bp->bio_disk == NULL)
490 				bp->bio_disk = dp;
491 			error = dp->d_getattr(bp);
492 			if (error != -1)
493 				break;
494 			error = EJUSTRETURN;
495 		}
496 		if (g_handleattr_int(bp, "GEOM::candelete",
497 		    (dp->d_flags & DISKFLAG_CANDELETE) != 0))
498 			break;
499 		else if (g_handleattr_int(bp, "GEOM::fwsectors",
500 		    dp->d_fwsectors))
501 			break;
502 		else if (g_handleattr_int(bp, "GEOM::fwheads", dp->d_fwheads))
503 			break;
504 		else if (g_handleattr_off_t(bp, "GEOM::frontstuff", 0))
505 			break;
506 		else if (g_handleattr_str(bp, "GEOM::ident", dp->d_ident))
507 			break;
508 		else if (g_handleattr_str(bp, "GEOM::descr", dp->d_descr))
509 			break;
510 		else if (g_handleattr_uint16_t(bp, "GEOM::hba_vendor",
511 		    dp->d_hba_vendor))
512 			break;
513 		else if (g_handleattr_uint16_t(bp, "GEOM::hba_device",
514 		    dp->d_hba_device))
515 			break;
516 		else if (g_handleattr_uint16_t(bp, "GEOM::hba_subvendor",
517 		    dp->d_hba_subvendor))
518 			break;
519 		else if (g_handleattr_uint16_t(bp, "GEOM::hba_subdevice",
520 		    dp->d_hba_subdevice))
521 			break;
522 		else if (!strcmp(bp->bio_attribute, "GEOM::kerneldump"))
523 			g_disk_kerneldump(bp, dp);
524 		else if (!strcmp(bp->bio_attribute, "GEOM::setstate"))
525 			g_disk_setstate(bp, sc);
526 		else if (g_handleattr_uint16_t(bp, "GEOM::rotation_rate",
527 		    dp->d_rotation_rate))
528 			break;
529 		else if (g_handleattr_str(bp, "GEOM::attachment",
530 		    dp->d_attachment))
531 			break;
532 		else
533 			error = ENOIOCTL;
534 		break;
535 	case BIO_FLUSH:
536 		g_trace(G_T_BIO, "g_disk_flushcache(%s)",
537 		    bp->bio_to->name);
538 		if (!(dp->d_flags & DISKFLAG_CANFLUSHCACHE)) {
539 			error = EOPNOTSUPP;
540 			break;
541 		}
542 		/*FALLTHROUGH*/
543 	case BIO_ZONE:
544 		if (bp->bio_cmd == BIO_ZONE) {
545 			if (!(dp->d_flags & DISKFLAG_CANZONE)) {
546 				error = EOPNOTSUPP;
547 				break;
548 			}
549 			g_trace(G_T_BIO, "g_disk_zone(%s)",
550 			    bp->bio_to->name);
551 		}
552 		bp2 = g_clone_bio(bp);
553 		if (bp2 == NULL) {
554 			g_io_deliver(bp, ENOMEM);
555 			return;
556 		}
557 		bp2->bio_done = g_disk_done;
558 		bp2->bio_disk = dp;
559 		devstat_start_transaction_bio(dp->d_devstat, bp2);
560 		dp->d_strategy(bp2);
561 		break;
562 	default:
563 		error = EOPNOTSUPP;
564 		break;
565 	}
566 	if (error != EJUSTRETURN)
567 		g_io_deliver(bp, error);
568 	return;
569 }
570 
571 static void
572 g_disk_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
573 {
574 	struct bio *bp;
575 	struct disk *dp;
576 	struct g_disk_softc *sc;
577 	char *buf;
578 	int res = 0;
579 
580 	sc = gp->softc;
581 	if (sc == NULL || (dp = sc->dp) == NULL)
582 		return;
583 	if (indent == NULL) {
584 		sbuf_printf(sb, " hd %u", dp->d_fwheads);
585 		sbuf_printf(sb, " sc %u", dp->d_fwsectors);
586 		return;
587 	}
588 	if (pp != NULL) {
589 		sbuf_printf(sb, "%s<fwheads>%u</fwheads>\n",
590 		    indent, dp->d_fwheads);
591 		sbuf_printf(sb, "%s<fwsectors>%u</fwsectors>\n",
592 		    indent, dp->d_fwsectors);
593 
594 		/*
595 		 * "rotationrate" is a little complicated, because the value
596 		 * returned by the drive might not be the RPM; 0 and 1 are
597 		 * special cases, and there's also a valid range.
598 		 */
599 		sbuf_printf(sb, "%s<rotationrate>", indent);
600 		if (dp->d_rotation_rate == DISK_RR_UNKNOWN) /* Old drives */
601 			sbuf_cat(sb, "unknown");	/* don't report RPM. */
602 		else if (dp->d_rotation_rate == DISK_RR_NON_ROTATING)
603 			sbuf_cat(sb, "0");
604 		else if ((dp->d_rotation_rate >= DISK_RR_MIN) &&
605 		    (dp->d_rotation_rate <= DISK_RR_MAX))
606 			sbuf_printf(sb, "%u", dp->d_rotation_rate);
607 		else
608 			sbuf_cat(sb, "invalid");
609 		sbuf_cat(sb, "</rotationrate>\n");
610 		if (dp->d_getattr != NULL) {
611 			buf = g_malloc(DISK_IDENT_SIZE, M_WAITOK);
612 			bp = g_alloc_bio();
613 			bp->bio_disk = dp;
614 			bp->bio_attribute = "GEOM::ident";
615 			bp->bio_length = DISK_IDENT_SIZE;
616 			bp->bio_data = buf;
617 			res = dp->d_getattr(bp);
618 			sbuf_printf(sb, "%s<ident>", indent);
619 			g_conf_cat_escaped(sb, res == 0 ? buf : dp->d_ident);
620 			sbuf_cat(sb, "</ident>\n");
621 			bp->bio_attribute = "GEOM::lunid";
622 			bp->bio_length = DISK_IDENT_SIZE;
623 			bp->bio_data = buf;
624 			if (dp->d_getattr(bp) == 0) {
625 				sbuf_printf(sb, "%s<lunid>", indent);
626 				g_conf_cat_escaped(sb, buf);
627 				sbuf_cat(sb, "</lunid>\n");
628 			}
629 			bp->bio_attribute = "GEOM::lunname";
630 			bp->bio_length = DISK_IDENT_SIZE;
631 			bp->bio_data = buf;
632 			if (dp->d_getattr(bp) == 0) {
633 				sbuf_printf(sb, "%s<lunname>", indent);
634 				g_conf_cat_escaped(sb, buf);
635 				sbuf_cat(sb, "</lunname>\n");
636 			}
637 			g_destroy_bio(bp);
638 			g_free(buf);
639 		} else {
640 			sbuf_printf(sb, "%s<ident>", indent);
641 			g_conf_cat_escaped(sb, dp->d_ident);
642 			sbuf_cat(sb, "</ident>\n");
643 		}
644 		sbuf_printf(sb, "%s<descr>", indent);
645 		g_conf_cat_escaped(sb, dp->d_descr);
646 		sbuf_cat(sb, "</descr>\n");
647 	}
648 }
649 
650 static void
651 g_disk_resize(void *ptr, int flag)
652 {
653 	struct disk *dp;
654 	struct g_geom *gp;
655 	struct g_provider *pp;
656 
657 	if (flag == EV_CANCEL)
658 		return;
659 	g_topology_assert();
660 
661 	dp = ptr;
662 	gp = dp->d_geom;
663 
664 	if (dp->d_destroyed || gp == NULL)
665 		return;
666 
667 	LIST_FOREACH(pp, &gp->provider, provider) {
668 		if (pp->sectorsize != 0 &&
669 		    pp->sectorsize != dp->d_sectorsize)
670 			g_wither_provider(pp, ENXIO);
671 		else
672 			g_resize_provider(pp, dp->d_mediasize);
673 	}
674 }
675 
676 static void
677 g_disk_create(void *arg, int flag)
678 {
679 	struct g_geom *gp;
680 	struct g_provider *pp;
681 	struct disk *dp;
682 	struct g_disk_softc *sc;
683 	struct disk_alias *dap;
684 	char tmpstr[80];
685 
686 	if (flag == EV_CANCEL)
687 		return;
688 	g_topology_assert();
689 	dp = arg;
690 
691 	mtx_pool_lock(mtxpool_sleep, dp);
692 	dp->d_init_level = DISK_INIT_START;
693 
694 	/*
695 	 * If the disk has already gone away, we can just stop here and
696 	 * call the user's callback to tell him we've cleaned things up.
697 	 */
698 	if (dp->d_goneflag != 0) {
699 		mtx_pool_unlock(mtxpool_sleep, dp);
700 		if (dp->d_gone != NULL)
701 			dp->d_gone(dp);
702 		return;
703 	}
704 	mtx_pool_unlock(mtxpool_sleep, dp);
705 
706 	sc = g_malloc(sizeof(*sc), M_WAITOK | M_ZERO);
707 	mtx_init(&sc->done_mtx, "g_disk_done", NULL, MTX_DEF);
708 	sc->dp = dp;
709 	gp = g_new_geomf(&g_disk_class, "%s%d", dp->d_name, dp->d_unit);
710 	gp->softc = sc;
711 	LIST_FOREACH(dap, &dp->d_aliases, da_next) {
712 		snprintf(tmpstr, sizeof(tmpstr), "%s%d", dap->da_alias, dp->d_unit);
713 		g_geom_add_alias(gp, tmpstr);
714 	}
715 	pp = g_new_providerf(gp, "%s", gp->name);
716 	devstat_remove_entry(pp->stat);
717 	pp->stat = NULL;
718 	dp->d_devstat->id = pp;
719 	pp->mediasize = dp->d_mediasize;
720 	pp->sectorsize = dp->d_sectorsize;
721 	pp->stripeoffset = dp->d_stripeoffset;
722 	pp->stripesize = dp->d_stripesize;
723 	if ((dp->d_flags & DISKFLAG_UNMAPPED_BIO) != 0)
724 		pp->flags |= G_PF_ACCEPT_UNMAPPED;
725 	if ((dp->d_flags & DISKFLAG_DIRECT_COMPLETION) != 0)
726 		pp->flags |= G_PF_DIRECT_SEND;
727 	pp->flags |= G_PF_DIRECT_RECEIVE;
728 	if (bootverbose)
729 		printf("GEOM: new disk %s\n", gp->name);
730 	sysctl_ctx_init(&sc->sysctl_ctx);
731 	snprintf(tmpstr, sizeof(tmpstr), "GEOM disk %s", gp->name);
732 	sc->sysctl_tree = SYSCTL_ADD_NODE(&sc->sysctl_ctx,
733 		SYSCTL_STATIC_CHILDREN(_kern_geom_disk), OID_AUTO, gp->name,
734 		CTLFLAG_RD, 0, tmpstr);
735 	if (sc->sysctl_tree != NULL) {
736 		SYSCTL_ADD_STRING(&sc->sysctl_ctx,
737 		    SYSCTL_CHILDREN(sc->sysctl_tree), OID_AUTO, "led",
738 		    CTLFLAG_RWTUN, sc->led, sizeof(sc->led),
739 		    "LED name");
740 		SYSCTL_ADD_PROC(&sc->sysctl_ctx,
741 		    SYSCTL_CHILDREN(sc->sysctl_tree), OID_AUTO, "flags",
742 		    CTLTYPE_STRING | CTLFLAG_RD, dp, 0, g_disk_sysctl_flags,
743 		    "A", "Report disk flags");
744 	}
745 	pp->private = sc;
746 	dp->d_geom = gp;
747 	g_error_provider(pp, 0);
748 
749 	mtx_pool_lock(mtxpool_sleep, dp);
750 	dp->d_init_level = DISK_INIT_DONE;
751 
752 	/*
753 	 * If the disk has gone away at this stage, start the withering
754 	 * process for it.
755 	 */
756 	if (dp->d_goneflag != 0) {
757 		mtx_pool_unlock(mtxpool_sleep, dp);
758 		g_wither_provider(pp, ENXIO);
759 		return;
760 	}
761 	mtx_pool_unlock(mtxpool_sleep, dp);
762 
763 }
764 
765 /*
766  * We get this callback after all of the consumers have gone away, and just
767  * before the provider is freed.  If the disk driver provided a d_gone
768  * callback, let them know that it is okay to free resources -- they won't
769  * be getting any more accesses from GEOM.
770  */
771 static void
772 g_disk_providergone(struct g_provider *pp)
773 {
774 	struct disk *dp;
775 	struct g_disk_softc *sc;
776 
777 	sc = (struct g_disk_softc *)pp->private;
778 	dp = sc->dp;
779 	if (dp != NULL && dp->d_gone != NULL)
780 		dp->d_gone(dp);
781 	if (sc->sysctl_tree != NULL) {
782 		sysctl_ctx_free(&sc->sysctl_ctx);
783 		sc->sysctl_tree = NULL;
784 	}
785 	if (sc->led[0] != 0) {
786 		led_set(sc->led, "0");
787 		sc->led[0] = 0;
788 	}
789 	pp->private = NULL;
790 	pp->geom->softc = NULL;
791 	mtx_destroy(&sc->done_mtx);
792 	g_free(sc);
793 }
794 
795 static void
796 g_disk_destroy(void *ptr, int flag)
797 {
798 	struct disk *dp;
799 	struct g_geom *gp;
800 	struct g_disk_softc *sc;
801 	struct disk_alias *dap, *daptmp;
802 
803 	g_topology_assert();
804 	dp = ptr;
805 	gp = dp->d_geom;
806 	if (gp != NULL) {
807 		sc = gp->softc;
808 		if (sc != NULL)
809 			sc->dp = NULL;
810 		dp->d_geom = NULL;
811 		g_wither_geom(gp, ENXIO);
812 	}
813 	LIST_FOREACH_SAFE(dap, &dp->d_aliases, da_next, daptmp)
814 		g_free(dap);
815 
816 	g_free(dp);
817 }
818 
819 /*
820  * We only allow printable characters in disk ident,
821  * the rest is converted to 'x<HH>'.
822  */
823 static void
824 g_disk_ident_adjust(char *ident, size_t size)
825 {
826 	char *p, tmp[4], newid[DISK_IDENT_SIZE];
827 
828 	newid[0] = '\0';
829 	for (p = ident; *p != '\0'; p++) {
830 		if (isprint(*p)) {
831 			tmp[0] = *p;
832 			tmp[1] = '\0';
833 		} else {
834 			snprintf(tmp, sizeof(tmp), "x%02hhx",
835 			    *(unsigned char *)p);
836 		}
837 		if (strlcat(newid, tmp, sizeof(newid)) >= sizeof(newid))
838 			break;
839 	}
840 	bzero(ident, size);
841 	strlcpy(ident, newid, size);
842 }
843 
844 struct disk *
845 disk_alloc(void)
846 {
847 	struct disk *dp;
848 
849 	dp = g_malloc(sizeof(struct disk), M_WAITOK | M_ZERO);
850 	LIST_INIT(&dp->d_aliases);
851 	return (dp);
852 }
853 
854 void
855 disk_create(struct disk *dp, int version)
856 {
857 
858 	if (version != DISK_VERSION) {
859 		printf("WARNING: Attempt to add disk %s%d %s",
860 		    dp->d_name, dp->d_unit,
861 		    " using incompatible ABI version of disk(9)\n");
862 		printf("WARNING: Ignoring disk %s%d\n",
863 		    dp->d_name, dp->d_unit);
864 		return;
865 	}
866 	if (dp->d_flags & DISKFLAG_RESERVED) {
867 		printf("WARNING: Attempt to add non-MPSAFE disk %s%d\n",
868 		    dp->d_name, dp->d_unit);
869 		printf("WARNING: Ignoring disk %s%d\n",
870 		    dp->d_name, dp->d_unit);
871 		return;
872 	}
873 	KASSERT(dp->d_strategy != NULL, ("disk_create need d_strategy"));
874 	KASSERT(dp->d_name != NULL, ("disk_create need d_name"));
875 	KASSERT(*dp->d_name != 0, ("disk_create need d_name"));
876 	KASSERT(strlen(dp->d_name) < SPECNAMELEN - 4, ("disk name too long"));
877 	if (dp->d_devstat == NULL)
878 		dp->d_devstat = devstat_new_entry(dp->d_name, dp->d_unit,
879 		    dp->d_sectorsize, DEVSTAT_ALL_SUPPORTED,
880 		    DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
881 	dp->d_geom = NULL;
882 
883 	dp->d_init_level = DISK_INIT_NONE;
884 
885 	g_disk_ident_adjust(dp->d_ident, sizeof(dp->d_ident));
886 	g_post_event(g_disk_create, dp, M_WAITOK, dp, NULL);
887 }
888 
889 void
890 disk_destroy(struct disk *dp)
891 {
892 
893 	disk_gone(dp);
894 	dp->d_destroyed = 1;
895 	g_cancel_event(dp);
896 	if (dp->d_devstat != NULL)
897 		devstat_remove_entry(dp->d_devstat);
898 	g_post_event(g_disk_destroy, dp, M_WAITOK, NULL);
899 }
900 
901 void
902 disk_add_alias(struct disk *dp, const char *name)
903 {
904 	struct disk_alias *dap;
905 
906 	dap = (struct disk_alias *)g_malloc(
907 		sizeof(struct disk_alias) + strlen(name) + 1, M_WAITOK);
908 	strcpy((char *)(dap + 1), name);
909 	dap->da_alias = (const char *)(dap + 1);
910 	LIST_INSERT_HEAD(&dp->d_aliases, dap, da_next);
911 }
912 
913 void
914 disk_gone(struct disk *dp)
915 {
916 	struct g_geom *gp;
917 	struct g_provider *pp;
918 
919 	mtx_pool_lock(mtxpool_sleep, dp);
920 
921 	/*
922 	 * Second wither call makes no sense, plus we can not access the list
923 	 * of providers without topology lock after calling wither once.
924 	 */
925 	if (dp->d_goneflag != 0) {
926 		mtx_pool_unlock(mtxpool_sleep, dp);
927 		return;
928 	}
929 
930 	dp->d_goneflag = 1;
931 
932 	/*
933 	 * If we're still in the process of creating this disk (the
934 	 * g_disk_create() function is still queued, or is in
935 	 * progress), the init level will not yet be DISK_INIT_DONE.
936 	 *
937 	 * If that is the case, g_disk_create() will see d_goneflag
938 	 * and take care of cleaning things up.
939 	 *
940 	 * If the disk has already been created, we default to
941 	 * withering the provider as usual below.
942 	 *
943 	 * If the caller has not set a d_gone() callback, he will
944 	 * not be any worse off by returning here, because the geom
945 	 * has not been fully setup in any case.
946 	 */
947 	if (dp->d_init_level < DISK_INIT_DONE) {
948 		mtx_pool_unlock(mtxpool_sleep, dp);
949 		return;
950 	}
951 	mtx_pool_unlock(mtxpool_sleep, dp);
952 
953 	gp = dp->d_geom;
954 	pp = LIST_FIRST(&gp->provider);
955 	if (pp != NULL) {
956 		KASSERT(LIST_NEXT(pp, provider) == NULL,
957 		    ("geom %p has more than one provider", gp));
958 		g_wither_provider(pp, ENXIO);
959 	}
960 }
961 
962 void
963 disk_attr_changed(struct disk *dp, const char *attr, int flag)
964 {
965 	struct g_geom *gp;
966 	struct g_provider *pp;
967 	char devnamebuf[128];
968 
969 	gp = dp->d_geom;
970 	if (gp != NULL)
971 		LIST_FOREACH(pp, &gp->provider, provider)
972 			(void)g_attr_changed(pp, attr, flag);
973 	snprintf(devnamebuf, sizeof(devnamebuf), "devname=%s%d", dp->d_name,
974 	    dp->d_unit);
975 	devctl_notify("GEOM", "disk", attr, devnamebuf);
976 }
977 
978 void
979 disk_media_changed(struct disk *dp, int flag)
980 {
981 	struct g_geom *gp;
982 	struct g_provider *pp;
983 
984 	gp = dp->d_geom;
985 	if (gp != NULL) {
986 		pp = LIST_FIRST(&gp->provider);
987 		if (pp != NULL) {
988 			KASSERT(LIST_NEXT(pp, provider) == NULL,
989 			    ("geom %p has more than one provider", gp));
990 			g_media_changed(pp, flag);
991 		}
992 	}
993 }
994 
995 void
996 disk_media_gone(struct disk *dp, int flag)
997 {
998 	struct g_geom *gp;
999 	struct g_provider *pp;
1000 
1001 	gp = dp->d_geom;
1002 	if (gp != NULL) {
1003 		pp = LIST_FIRST(&gp->provider);
1004 		if (pp != NULL) {
1005 			KASSERT(LIST_NEXT(pp, provider) == NULL,
1006 			    ("geom %p has more than one provider", gp));
1007 			g_media_gone(pp, flag);
1008 		}
1009 	}
1010 }
1011 
1012 int
1013 disk_resize(struct disk *dp, int flag)
1014 {
1015 
1016 	if (dp->d_destroyed || dp->d_geom == NULL)
1017 		return (0);
1018 
1019 	return (g_post_event(g_disk_resize, dp, flag, NULL));
1020 }
1021 
1022 static void
1023 g_kern_disks(void *p, int flag __unused)
1024 {
1025 	struct sbuf *sb;
1026 	struct g_geom *gp;
1027 	char *sp;
1028 
1029 	sb = p;
1030 	sp = "";
1031 	g_topology_assert();
1032 	LIST_FOREACH(gp, &g_disk_class.geom, geom) {
1033 		sbuf_printf(sb, "%s%s", sp, gp->name);
1034 		sp = " ";
1035 	}
1036 	sbuf_finish(sb);
1037 }
1038 
1039 static int
1040 g_disk_sysctl_flags(SYSCTL_HANDLER_ARGS)
1041 {
1042 	struct disk *dp;
1043 	struct sbuf *sb;
1044 	int error;
1045 
1046 	sb = sbuf_new_auto();
1047 	dp = (struct disk *)arg1;
1048 	sbuf_printf(sb, "%b", dp->d_flags,
1049 		"\20"
1050 		"\2OPEN"
1051 		"\3CANDELETE"
1052 		"\4CANFLUSHCACHE"
1053 		"\5UNMAPPEDBIO"
1054 		"\6DIRECTCOMPLETION"
1055 		"\10CANZONE"
1056 		"\11WRITEPROTECT");
1057 
1058 	sbuf_finish(sb);
1059 	error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
1060 	sbuf_delete(sb);
1061 	return (error);
1062 }
1063 
1064 static int
1065 sysctl_disks(SYSCTL_HANDLER_ARGS)
1066 {
1067 	int error;
1068 	struct sbuf *sb;
1069 
1070 	sb = sbuf_new_auto();
1071 	g_waitfor_event(g_kern_disks, sb, M_WAITOK, NULL);
1072 	error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
1073 	sbuf_delete(sb);
1074 	return error;
1075 }
1076 
1077 SYSCTL_PROC(_kern, OID_AUTO, disks,
1078     CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
1079     sysctl_disks, "A", "names of available disks");
1080