xref: /freebsd/sys/geom/stripe/g_stripe.c (revision 9268022b74279434ed6300244e3f977e56a8ceb5)
1 /*-
2  * Copyright (c) 2004-2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/module.h>
34 #include <sys/lock.h>
35 #include <sys/mutex.h>
36 #include <sys/bio.h>
37 #include <sys/sbuf.h>
38 #include <sys/sysctl.h>
39 #include <sys/malloc.h>
40 #include <vm/uma.h>
41 #include <geom/geom.h>
42 #include <geom/stripe/g_stripe.h>
43 
44 FEATURE(geom_stripe, "GEOM striping support");
45 
46 static MALLOC_DEFINE(M_STRIPE, "stripe_data", "GEOM_STRIPE Data");
47 
48 static uma_zone_t g_stripe_zone;
49 
50 static int g_stripe_destroy(struct g_stripe_softc *sc, boolean_t force);
51 static int g_stripe_destroy_geom(struct gctl_req *req, struct g_class *mp,
52     struct g_geom *gp);
53 
54 static g_taste_t g_stripe_taste;
55 static g_ctl_req_t g_stripe_config;
56 static g_dumpconf_t g_stripe_dumpconf;
57 static g_init_t g_stripe_init;
58 static g_fini_t g_stripe_fini;
59 
60 struct g_class g_stripe_class = {
61 	.name = G_STRIPE_CLASS_NAME,
62 	.version = G_VERSION,
63 	.ctlreq = g_stripe_config,
64 	.taste = g_stripe_taste,
65 	.destroy_geom = g_stripe_destroy_geom,
66 	.init = g_stripe_init,
67 	.fini = g_stripe_fini
68 };
69 
70 SYSCTL_DECL(_kern_geom);
71 static SYSCTL_NODE(_kern_geom, OID_AUTO, stripe, CTLFLAG_RW, 0,
72     "GEOM_STRIPE stuff");
73 static u_int g_stripe_debug = 0;
74 SYSCTL_UINT(_kern_geom_stripe, OID_AUTO, debug, CTLFLAG_RWTUN, &g_stripe_debug, 0,
75     "Debug level");
76 static int g_stripe_fast = 0;
77 static int
78 g_sysctl_stripe_fast(SYSCTL_HANDLER_ARGS)
79 {
80 	int error, fast;
81 
82 	fast = g_stripe_fast;
83 	error = sysctl_handle_int(oidp, &fast, 0, req);
84 	if (error == 0 && req->newptr != NULL)
85 		g_stripe_fast = fast;
86 	return (error);
87 }
88 SYSCTL_PROC(_kern_geom_stripe, OID_AUTO, fast, CTLTYPE_INT | CTLFLAG_RWTUN,
89     NULL, 0, g_sysctl_stripe_fast, "I", "Fast, but memory-consuming, mode");
90 static u_int g_stripe_maxmem = MAXPHYS * 100;
91 SYSCTL_UINT(_kern_geom_stripe, OID_AUTO, maxmem, CTLFLAG_RDTUN, &g_stripe_maxmem,
92     0, "Maximum memory that can be allocated in \"fast\" mode (in bytes)");
93 static u_int g_stripe_fast_failed = 0;
94 SYSCTL_UINT(_kern_geom_stripe, OID_AUTO, fast_failed, CTLFLAG_RD,
95     &g_stripe_fast_failed, 0, "How many times \"fast\" mode failed");
96 
97 /*
98  * Greatest Common Divisor.
99  */
100 static u_int
101 gcd(u_int a, u_int b)
102 {
103 	u_int c;
104 
105 	while (b != 0) {
106 		c = a;
107 		a = b;
108 		b = (c % b);
109 	}
110 	return (a);
111 }
112 
113 /*
114  * Least Common Multiple.
115  */
116 static u_int
117 lcm(u_int a, u_int b)
118 {
119 
120 	return ((a * b) / gcd(a, b));
121 }
122 
123 static void
124 g_stripe_init(struct g_class *mp __unused)
125 {
126 
127 	g_stripe_zone = uma_zcreate("g_stripe_zone", MAXPHYS, NULL, NULL,
128 	    NULL, NULL, 0, 0);
129 	g_stripe_maxmem -= g_stripe_maxmem % MAXPHYS;
130 	uma_zone_set_max(g_stripe_zone, g_stripe_maxmem / MAXPHYS);
131 }
132 
133 static void
134 g_stripe_fini(struct g_class *mp __unused)
135 {
136 
137 	uma_zdestroy(g_stripe_zone);
138 }
139 
140 /*
141  * Return the number of valid disks.
142  */
143 static u_int
144 g_stripe_nvalid(struct g_stripe_softc *sc)
145 {
146 	u_int i, no;
147 
148 	no = 0;
149 	for (i = 0; i < sc->sc_ndisks; i++) {
150 		if (sc->sc_disks[i] != NULL)
151 			no++;
152 	}
153 
154 	return (no);
155 }
156 
157 static void
158 g_stripe_remove_disk(struct g_consumer *cp)
159 {
160 	struct g_stripe_softc *sc;
161 
162 	g_topology_assert();
163 	KASSERT(cp != NULL, ("Non-valid disk in %s.", __func__));
164 	sc = (struct g_stripe_softc *)cp->geom->softc;
165 	KASSERT(sc != NULL, ("NULL sc in %s.", __func__));
166 
167 	if (cp->private == NULL) {
168 		G_STRIPE_DEBUG(0, "Disk %s removed from %s.",
169 		    cp->provider->name, sc->sc_name);
170 		cp->private = (void *)(uintptr_t)-1;
171 	}
172 
173 	if (sc->sc_provider != NULL) {
174 		sc->sc_provider->flags |= G_PF_WITHER;
175 		G_STRIPE_DEBUG(0, "Device %s deactivated.",
176 		    sc->sc_provider->name);
177 		g_orphan_provider(sc->sc_provider, ENXIO);
178 		sc->sc_provider = NULL;
179 	}
180 
181 	if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
182 		return;
183 	sc->sc_disks[cp->index] = NULL;
184 	cp->index = 0;
185 	g_detach(cp);
186 	g_destroy_consumer(cp);
187 	/* If there are no valid disks anymore, remove device. */
188 	if (LIST_EMPTY(&sc->sc_geom->consumer))
189 		g_stripe_destroy(sc, 1);
190 }
191 
192 static void
193 g_stripe_orphan(struct g_consumer *cp)
194 {
195 	struct g_stripe_softc *sc;
196 	struct g_geom *gp;
197 
198 	g_topology_assert();
199 	gp = cp->geom;
200 	sc = gp->softc;
201 	if (sc == NULL)
202 		return;
203 
204 	g_stripe_remove_disk(cp);
205 }
206 
207 static int
208 g_stripe_access(struct g_provider *pp, int dr, int dw, int de)
209 {
210 	struct g_consumer *cp1, *cp2, *tmp;
211 	struct g_stripe_softc *sc;
212 	struct g_geom *gp;
213 	int error;
214 
215 	g_topology_assert();
216 	gp = pp->geom;
217 	sc = gp->softc;
218 	KASSERT(sc != NULL, ("NULL sc in %s.", __func__));
219 
220 	/* On first open, grab an extra "exclusive" bit */
221 	if (pp->acr == 0 && pp->acw == 0 && pp->ace == 0)
222 		de++;
223 	/* ... and let go of it on last close */
224 	if ((pp->acr + dr) == 0 && (pp->acw + dw) == 0 && (pp->ace + de) == 0)
225 		de--;
226 
227 	LIST_FOREACH_SAFE(cp1, &gp->consumer, consumer, tmp) {
228 		error = g_access(cp1, dr, dw, de);
229 		if (error != 0)
230 			goto fail;
231 		if (cp1->acr == 0 && cp1->acw == 0 && cp1->ace == 0 &&
232 		    cp1->private != NULL) {
233 			g_stripe_remove_disk(cp1); /* May destroy geom. */
234 		}
235 	}
236 	return (0);
237 
238 fail:
239 	LIST_FOREACH(cp2, &gp->consumer, consumer) {
240 		if (cp1 == cp2)
241 			break;
242 		g_access(cp2, -dr, -dw, -de);
243 	}
244 	return (error);
245 }
246 
247 static void
248 g_stripe_copy(struct g_stripe_softc *sc, char *src, char *dst, off_t offset,
249     off_t length, int mode)
250 {
251 	u_int stripesize;
252 	size_t len;
253 
254 	stripesize = sc->sc_stripesize;
255 	len = (size_t)(stripesize - (offset & (stripesize - 1)));
256 	do {
257 		bcopy(src, dst, len);
258 		if (mode) {
259 			dst += len + stripesize * (sc->sc_ndisks - 1);
260 			src += len;
261 		} else {
262 			dst += len;
263 			src += len + stripesize * (sc->sc_ndisks - 1);
264 		}
265 		length -= len;
266 		KASSERT(length >= 0,
267 		    ("Length < 0 (stripesize=%zu, offset=%jd, length=%jd).",
268 		    (size_t)stripesize, (intmax_t)offset, (intmax_t)length));
269 		if (length > stripesize)
270 			len = stripesize;
271 		else
272 			len = length;
273 	} while (length > 0);
274 }
275 
276 static void
277 g_stripe_done(struct bio *bp)
278 {
279 	struct g_stripe_softc *sc;
280 	struct bio *pbp;
281 
282 	pbp = bp->bio_parent;
283 	sc = pbp->bio_to->geom->softc;
284 	if (bp->bio_cmd == BIO_READ && bp->bio_caller1 != NULL) {
285 		g_stripe_copy(sc, bp->bio_data, bp->bio_caller1, bp->bio_offset,
286 		    bp->bio_length, 1);
287 		bp->bio_data = bp->bio_caller1;
288 		bp->bio_caller1 = NULL;
289 	}
290 	mtx_lock(&sc->sc_lock);
291 	if (pbp->bio_error == 0)
292 		pbp->bio_error = bp->bio_error;
293 	pbp->bio_completed += bp->bio_completed;
294 	pbp->bio_inbed++;
295 	if (pbp->bio_children == pbp->bio_inbed) {
296 		mtx_unlock(&sc->sc_lock);
297 		if (pbp->bio_driver1 != NULL)
298 			uma_zfree(g_stripe_zone, pbp->bio_driver1);
299 		g_io_deliver(pbp, pbp->bio_error);
300 	} else
301 		mtx_unlock(&sc->sc_lock);
302 	g_destroy_bio(bp);
303 }
304 
305 static int
306 g_stripe_start_fast(struct bio *bp, u_int no, off_t offset, off_t length)
307 {
308 	TAILQ_HEAD(, bio) queue = TAILQ_HEAD_INITIALIZER(queue);
309 	u_int nparts = 0, stripesize;
310 	struct g_stripe_softc *sc;
311 	char *addr, *data = NULL;
312 	struct bio *cbp;
313 	int error;
314 
315 	sc = bp->bio_to->geom->softc;
316 
317 	addr = bp->bio_data;
318 	stripesize = sc->sc_stripesize;
319 
320 	cbp = g_clone_bio(bp);
321 	if (cbp == NULL) {
322 		error = ENOMEM;
323 		goto failure;
324 	}
325 	TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
326 	nparts++;
327 	/*
328 	 * Fill in the component buf structure.
329 	 */
330 	cbp->bio_done = g_stripe_done;
331 	cbp->bio_offset = offset;
332 	cbp->bio_data = addr;
333 	cbp->bio_caller1 = NULL;
334 	cbp->bio_length = length;
335 	cbp->bio_caller2 = sc->sc_disks[no];
336 
337 	/* offset -= offset % stripesize; */
338 	offset -= offset & (stripesize - 1);
339 	addr += length;
340 	length = bp->bio_length - length;
341 	for (no++; length > 0; no++, length -= stripesize, addr += stripesize) {
342 		if (no > sc->sc_ndisks - 1) {
343 			no = 0;
344 			offset += stripesize;
345 		}
346 		if (nparts >= sc->sc_ndisks) {
347 			cbp = TAILQ_NEXT(cbp, bio_queue);
348 			if (cbp == NULL)
349 				cbp = TAILQ_FIRST(&queue);
350 			nparts++;
351 			/*
352 			 * Update bio structure.
353 			 */
354 			/*
355 			 * MIN() is in case when
356 			 * (bp->bio_length % sc->sc_stripesize) != 0.
357 			 */
358 			cbp->bio_length += MIN(stripesize, length);
359 			if (cbp->bio_caller1 == NULL) {
360 				cbp->bio_caller1 = cbp->bio_data;
361 				cbp->bio_data = NULL;
362 				if (data == NULL) {
363 					data = uma_zalloc(g_stripe_zone,
364 					    M_NOWAIT);
365 					if (data == NULL) {
366 						error = ENOMEM;
367 						goto failure;
368 					}
369 				}
370 			}
371 		} else {
372 			cbp = g_clone_bio(bp);
373 			if (cbp == NULL) {
374 				error = ENOMEM;
375 				goto failure;
376 			}
377 			TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
378 			nparts++;
379 			/*
380 			 * Fill in the component buf structure.
381 			 */
382 			cbp->bio_done = g_stripe_done;
383 			cbp->bio_offset = offset;
384 			cbp->bio_data = addr;
385 			cbp->bio_caller1 = NULL;
386 			/*
387 			 * MIN() is in case when
388 			 * (bp->bio_length % sc->sc_stripesize) != 0.
389 			 */
390 			cbp->bio_length = MIN(stripesize, length);
391 			cbp->bio_caller2 = sc->sc_disks[no];
392 		}
393 	}
394 	if (data != NULL)
395 		bp->bio_driver1 = data;
396 	/*
397 	 * Fire off all allocated requests!
398 	 */
399 	while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
400 		struct g_consumer *cp;
401 
402 		TAILQ_REMOVE(&queue, cbp, bio_queue);
403 		cp = cbp->bio_caller2;
404 		cbp->bio_caller2 = NULL;
405 		cbp->bio_to = cp->provider;
406 		if (cbp->bio_caller1 != NULL) {
407 			cbp->bio_data = data;
408 			if (bp->bio_cmd == BIO_WRITE) {
409 				g_stripe_copy(sc, cbp->bio_caller1, data,
410 				    cbp->bio_offset, cbp->bio_length, 0);
411 			}
412 			data += cbp->bio_length;
413 		}
414 		G_STRIPE_LOGREQ(cbp, "Sending request.");
415 		g_io_request(cbp, cp);
416 	}
417 	return (0);
418 failure:
419 	if (data != NULL)
420 		uma_zfree(g_stripe_zone, data);
421 	while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
422 		TAILQ_REMOVE(&queue, cbp, bio_queue);
423 		if (cbp->bio_caller1 != NULL) {
424 			cbp->bio_data = cbp->bio_caller1;
425 			cbp->bio_caller1 = NULL;
426 		}
427 		bp->bio_children--;
428 		g_destroy_bio(cbp);
429 	}
430 	return (error);
431 }
432 
433 static int
434 g_stripe_start_economic(struct bio *bp, u_int no, off_t offset, off_t length)
435 {
436 	TAILQ_HEAD(, bio) queue = TAILQ_HEAD_INITIALIZER(queue);
437 	struct g_stripe_softc *sc;
438 	uint32_t stripesize;
439 	struct bio *cbp;
440 	char *addr;
441 	int error;
442 
443 	sc = bp->bio_to->geom->softc;
444 
445 	stripesize = sc->sc_stripesize;
446 
447 	cbp = g_clone_bio(bp);
448 	if (cbp == NULL) {
449 		error = ENOMEM;
450 		goto failure;
451 	}
452 	TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
453 	/*
454 	 * Fill in the component buf structure.
455 	 */
456 	if (bp->bio_length == length)
457 		cbp->bio_done = g_std_done;	/* Optimized lockless case. */
458 	else
459 		cbp->bio_done = g_stripe_done;
460 	cbp->bio_offset = offset;
461 	cbp->bio_length = length;
462 	if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
463 		bp->bio_ma_n = round_page(bp->bio_ma_offset +
464 		    bp->bio_length) / PAGE_SIZE;
465 		addr = NULL;
466 	} else
467 		addr = bp->bio_data;
468 	cbp->bio_caller2 = sc->sc_disks[no];
469 
470 	/* offset -= offset % stripesize; */
471 	offset -= offset & (stripesize - 1);
472 	if (bp->bio_cmd != BIO_DELETE)
473 		addr += length;
474 	length = bp->bio_length - length;
475 	for (no++; length > 0; no++, length -= stripesize) {
476 		if (no > sc->sc_ndisks - 1) {
477 			no = 0;
478 			offset += stripesize;
479 		}
480 		cbp = g_clone_bio(bp);
481 		if (cbp == NULL) {
482 			error = ENOMEM;
483 			goto failure;
484 		}
485 		TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
486 
487 		/*
488 		 * Fill in the component buf structure.
489 		 */
490 		cbp->bio_done = g_stripe_done;
491 		cbp->bio_offset = offset;
492 		/*
493 		 * MIN() is in case when
494 		 * (bp->bio_length % sc->sc_stripesize) != 0.
495 		 */
496 		cbp->bio_length = MIN(stripesize, length);
497 		if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
498 			cbp->bio_ma_offset += (uintptr_t)addr;
499 			cbp->bio_ma += cbp->bio_ma_offset / PAGE_SIZE;
500 			cbp->bio_ma_offset %= PAGE_SIZE;
501 			cbp->bio_ma_n = round_page(cbp->bio_ma_offset +
502 			    cbp->bio_length) / PAGE_SIZE;
503 		} else
504 			cbp->bio_data = addr;
505 
506 		cbp->bio_caller2 = sc->sc_disks[no];
507 
508 		if (bp->bio_cmd != BIO_DELETE)
509 			addr += stripesize;
510 	}
511 	/*
512 	 * Fire off all allocated requests!
513 	 */
514 	while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
515 		struct g_consumer *cp;
516 
517 		TAILQ_REMOVE(&queue, cbp, bio_queue);
518 		cp = cbp->bio_caller2;
519 		cbp->bio_caller2 = NULL;
520 		cbp->bio_to = cp->provider;
521 		G_STRIPE_LOGREQ(cbp, "Sending request.");
522 		g_io_request(cbp, cp);
523 	}
524 	return (0);
525 failure:
526 	while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
527 		TAILQ_REMOVE(&queue, cbp, bio_queue);
528 		bp->bio_children--;
529 		g_destroy_bio(cbp);
530 	}
531 	return (error);
532 }
533 
534 static void
535 g_stripe_flush(struct g_stripe_softc *sc, struct bio *bp)
536 {
537 	struct bio_queue_head queue;
538 	struct g_consumer *cp;
539 	struct bio *cbp;
540 	u_int no;
541 
542 	bioq_init(&queue);
543 	for (no = 0; no < sc->sc_ndisks; no++) {
544 		cbp = g_clone_bio(bp);
545 		if (cbp == NULL) {
546 			for (cbp = bioq_first(&queue); cbp != NULL;
547 			    cbp = bioq_first(&queue)) {
548 				bioq_remove(&queue, cbp);
549 				g_destroy_bio(cbp);
550 			}
551 			if (bp->bio_error == 0)
552 				bp->bio_error = ENOMEM;
553 			g_io_deliver(bp, bp->bio_error);
554 			return;
555 		}
556 		bioq_insert_tail(&queue, cbp);
557 		cbp->bio_done = g_stripe_done;
558 		cbp->bio_caller2 = sc->sc_disks[no];
559 		cbp->bio_to = sc->sc_disks[no]->provider;
560 	}
561 	for (cbp = bioq_first(&queue); cbp != NULL; cbp = bioq_first(&queue)) {
562 		bioq_remove(&queue, cbp);
563 		G_STRIPE_LOGREQ(cbp, "Sending request.");
564 		cp = cbp->bio_caller2;
565 		cbp->bio_caller2 = NULL;
566 		g_io_request(cbp, cp);
567 	}
568 }
569 
570 static void
571 g_stripe_start(struct bio *bp)
572 {
573 	off_t offset, start, length, nstripe;
574 	struct g_stripe_softc *sc;
575 	u_int no, stripesize;
576 	int error, fast = 0;
577 
578 	sc = bp->bio_to->geom->softc;
579 	/*
580 	 * If sc == NULL, provider's error should be set and g_stripe_start()
581 	 * should not be called at all.
582 	 */
583 	KASSERT(sc != NULL,
584 	    ("Provider's error should be set (error=%d)(device=%s).",
585 	    bp->bio_to->error, bp->bio_to->name));
586 
587 	G_STRIPE_LOGREQ(bp, "Request received.");
588 
589 	switch (bp->bio_cmd) {
590 	case BIO_READ:
591 	case BIO_WRITE:
592 	case BIO_DELETE:
593 		break;
594 	case BIO_FLUSH:
595 		g_stripe_flush(sc, bp);
596 		return;
597 	case BIO_GETATTR:
598 		/* To which provider it should be delivered? */
599 	default:
600 		g_io_deliver(bp, EOPNOTSUPP);
601 		return;
602 	}
603 
604 	stripesize = sc->sc_stripesize;
605 
606 	/*
607 	 * Calculations are quite messy, but fast I hope.
608 	 */
609 
610 	/* Stripe number. */
611 	/* nstripe = bp->bio_offset / stripesize; */
612 	nstripe = bp->bio_offset >> (off_t)sc->sc_stripebits;
613 	/* Disk number. */
614 	no = nstripe % sc->sc_ndisks;
615 	/* Start position in stripe. */
616 	/* start = bp->bio_offset % stripesize; */
617 	start = bp->bio_offset & (stripesize - 1);
618 	/* Start position in disk. */
619 	/* offset = (nstripe / sc->sc_ndisks) * stripesize + start; */
620 	offset = ((nstripe / sc->sc_ndisks) << sc->sc_stripebits) + start;
621 	/* Length of data to operate. */
622 	length = MIN(bp->bio_length, stripesize - start);
623 
624 	/*
625 	 * Do use "fast" mode when:
626 	 * 1. "Fast" mode is ON.
627 	 * and
628 	 * 2. Request size is less than or equal to MAXPHYS,
629 	 *    which should always be true.
630 	 * and
631 	 * 3. Request size is bigger than stripesize * ndisks. If it isn't,
632 	 *    there will be no need to send more than one I/O request to
633 	 *    a provider, so there is nothing to optmize.
634 	 * and
635 	 * 4. Request is not unmapped.
636 	 * and
637 	 * 5. It is not a BIO_DELETE.
638 	 */
639 	if (g_stripe_fast && bp->bio_length <= MAXPHYS &&
640 	    bp->bio_length >= stripesize * sc->sc_ndisks &&
641 	    (bp->bio_flags & BIO_UNMAPPED) == 0 &&
642 	    bp->bio_cmd != BIO_DELETE) {
643 		fast = 1;
644 	}
645 	error = 0;
646 	if (fast) {
647 		error = g_stripe_start_fast(bp, no, offset, length);
648 		if (error != 0)
649 			g_stripe_fast_failed++;
650 	}
651 	/*
652 	 * Do use "economic" when:
653 	 * 1. "Economic" mode is ON.
654 	 * or
655 	 * 2. "Fast" mode failed. It can only fail if there is no memory.
656 	 */
657 	if (!fast || error != 0)
658 		error = g_stripe_start_economic(bp, no, offset, length);
659 	if (error != 0) {
660 		if (bp->bio_error == 0)
661 			bp->bio_error = error;
662 		g_io_deliver(bp, bp->bio_error);
663 	}
664 }
665 
666 static void
667 g_stripe_check_and_run(struct g_stripe_softc *sc)
668 {
669 	struct g_provider *dp;
670 	off_t mediasize, ms;
671 	u_int no, sectorsize = 0;
672 
673 	g_topology_assert();
674 	if (g_stripe_nvalid(sc) != sc->sc_ndisks)
675 		return;
676 
677 	sc->sc_provider = g_new_providerf(sc->sc_geom, "stripe/%s",
678 	    sc->sc_name);
679 	sc->sc_provider->flags |= G_PF_DIRECT_SEND | G_PF_DIRECT_RECEIVE;
680 	if (g_stripe_fast == 0)
681 		sc->sc_provider->flags |= G_PF_ACCEPT_UNMAPPED;
682 	/*
683 	 * Find the smallest disk.
684 	 */
685 	mediasize = sc->sc_disks[0]->provider->mediasize;
686 	if (sc->sc_type == G_STRIPE_TYPE_AUTOMATIC)
687 		mediasize -= sc->sc_disks[0]->provider->sectorsize;
688 	mediasize -= mediasize % sc->sc_stripesize;
689 	sectorsize = sc->sc_disks[0]->provider->sectorsize;
690 	for (no = 1; no < sc->sc_ndisks; no++) {
691 		dp = sc->sc_disks[no]->provider;
692 		ms = dp->mediasize;
693 		if (sc->sc_type == G_STRIPE_TYPE_AUTOMATIC)
694 			ms -= dp->sectorsize;
695 		ms -= ms % sc->sc_stripesize;
696 		if (ms < mediasize)
697 			mediasize = ms;
698 		sectorsize = lcm(sectorsize, dp->sectorsize);
699 
700 		/* A provider underneath us doesn't support unmapped */
701 		if ((dp->flags & G_PF_ACCEPT_UNMAPPED) == 0) {
702 			G_STRIPE_DEBUG(1, "Cancelling unmapped "
703 			    "because of %s.", dp->name);
704 			sc->sc_provider->flags &= ~G_PF_ACCEPT_UNMAPPED;
705 		}
706 	}
707 	sc->sc_provider->sectorsize = sectorsize;
708 	sc->sc_provider->mediasize = mediasize * sc->sc_ndisks;
709 	sc->sc_provider->stripesize = sc->sc_stripesize;
710 	sc->sc_provider->stripeoffset = 0;
711 	g_error_provider(sc->sc_provider, 0);
712 
713 	G_STRIPE_DEBUG(0, "Device %s activated.", sc->sc_provider->name);
714 }
715 
716 static int
717 g_stripe_read_metadata(struct g_consumer *cp, struct g_stripe_metadata *md)
718 {
719 	struct g_provider *pp;
720 	u_char *buf;
721 	int error;
722 
723 	g_topology_assert();
724 
725 	error = g_access(cp, 1, 0, 0);
726 	if (error != 0)
727 		return (error);
728 	pp = cp->provider;
729 	g_topology_unlock();
730 	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
731 	    &error);
732 	g_topology_lock();
733 	g_access(cp, -1, 0, 0);
734 	if (buf == NULL)
735 		return (error);
736 
737 	/* Decode metadata. */
738 	stripe_metadata_decode(buf, md);
739 	g_free(buf);
740 
741 	return (0);
742 }
743 
744 /*
745  * Add disk to given device.
746  */
747 static int
748 g_stripe_add_disk(struct g_stripe_softc *sc, struct g_provider *pp, u_int no)
749 {
750 	struct g_consumer *cp, *fcp;
751 	struct g_geom *gp;
752 	int error;
753 
754 	g_topology_assert();
755 	/* Metadata corrupted? */
756 	if (no >= sc->sc_ndisks)
757 		return (EINVAL);
758 
759 	/* Check if disk is not already attached. */
760 	if (sc->sc_disks[no] != NULL)
761 		return (EEXIST);
762 
763 	gp = sc->sc_geom;
764 	fcp = LIST_FIRST(&gp->consumer);
765 
766 	cp = g_new_consumer(gp);
767 	cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE;
768 	cp->private = NULL;
769 	cp->index = no;
770 	error = g_attach(cp, pp);
771 	if (error != 0) {
772 		g_destroy_consumer(cp);
773 		return (error);
774 	}
775 
776 	if (fcp != NULL && (fcp->acr > 0 || fcp->acw > 0 || fcp->ace > 0)) {
777 		error = g_access(cp, fcp->acr, fcp->acw, fcp->ace);
778 		if (error != 0) {
779 			g_detach(cp);
780 			g_destroy_consumer(cp);
781 			return (error);
782 		}
783 	}
784 	if (sc->sc_type == G_STRIPE_TYPE_AUTOMATIC) {
785 		struct g_stripe_metadata md;
786 
787 		/* Reread metadata. */
788 		error = g_stripe_read_metadata(cp, &md);
789 		if (error != 0)
790 			goto fail;
791 
792 		if (strcmp(md.md_magic, G_STRIPE_MAGIC) != 0 ||
793 		    strcmp(md.md_name, sc->sc_name) != 0 ||
794 		    md.md_id != sc->sc_id) {
795 			G_STRIPE_DEBUG(0, "Metadata on %s changed.", pp->name);
796 			goto fail;
797 		}
798 	}
799 
800 	sc->sc_disks[no] = cp;
801 	G_STRIPE_DEBUG(0, "Disk %s attached to %s.", pp->name, sc->sc_name);
802 	g_stripe_check_and_run(sc);
803 
804 	return (0);
805 fail:
806 	if (fcp != NULL && (fcp->acr > 0 || fcp->acw > 0 || fcp->ace > 0))
807 		g_access(cp, -fcp->acr, -fcp->acw, -fcp->ace);
808 	g_detach(cp);
809 	g_destroy_consumer(cp);
810 	return (error);
811 }
812 
813 static struct g_geom *
814 g_stripe_create(struct g_class *mp, const struct g_stripe_metadata *md,
815     u_int type)
816 {
817 	struct g_stripe_softc *sc;
818 	struct g_geom *gp;
819 	u_int no;
820 
821 	g_topology_assert();
822 	G_STRIPE_DEBUG(1, "Creating device %s (id=%u).", md->md_name,
823 	    md->md_id);
824 
825 	/* Two disks is minimum. */
826 	if (md->md_all < 2) {
827 		G_STRIPE_DEBUG(0, "Too few disks defined for %s.", md->md_name);
828 		return (NULL);
829 	}
830 #if 0
831 	/* Stripe size have to be grater than or equal to sector size. */
832 	if (md->md_stripesize < sectorsize) {
833 		G_STRIPE_DEBUG(0, "Invalid stripe size for %s.", md->md_name);
834 		return (NULL);
835 	}
836 #endif
837 	/* Stripe size have to be power of 2. */
838 	if (!powerof2(md->md_stripesize)) {
839 		G_STRIPE_DEBUG(0, "Invalid stripe size for %s.", md->md_name);
840 		return (NULL);
841 	}
842 
843 	/* Check for duplicate unit */
844 	LIST_FOREACH(gp, &mp->geom, geom) {
845 		sc = gp->softc;
846 		if (sc != NULL && strcmp(sc->sc_name, md->md_name) == 0) {
847 			G_STRIPE_DEBUG(0, "Device %s already configured.",
848 			    sc->sc_name);
849 			return (NULL);
850 		}
851 	}
852 	gp = g_new_geomf(mp, "%s", md->md_name);
853 	sc = malloc(sizeof(*sc), M_STRIPE, M_WAITOK | M_ZERO);
854 	gp->start = g_stripe_start;
855 	gp->spoiled = g_stripe_orphan;
856 	gp->orphan = g_stripe_orphan;
857 	gp->access = g_stripe_access;
858 	gp->dumpconf = g_stripe_dumpconf;
859 
860 	sc->sc_id = md->md_id;
861 	sc->sc_stripesize = md->md_stripesize;
862 	sc->sc_stripebits = bitcount32(sc->sc_stripesize - 1);
863 	sc->sc_ndisks = md->md_all;
864 	sc->sc_disks = malloc(sizeof(struct g_consumer *) * sc->sc_ndisks,
865 	    M_STRIPE, M_WAITOK | M_ZERO);
866 	for (no = 0; no < sc->sc_ndisks; no++)
867 		sc->sc_disks[no] = NULL;
868 	sc->sc_type = type;
869 	mtx_init(&sc->sc_lock, "gstripe lock", NULL, MTX_DEF);
870 
871 	gp->softc = sc;
872 	sc->sc_geom = gp;
873 	sc->sc_provider = NULL;
874 
875 	G_STRIPE_DEBUG(0, "Device %s created (id=%u).", sc->sc_name, sc->sc_id);
876 
877 	return (gp);
878 }
879 
880 static int
881 g_stripe_destroy(struct g_stripe_softc *sc, boolean_t force)
882 {
883 	struct g_provider *pp;
884 	struct g_consumer *cp, *cp1;
885 	struct g_geom *gp;
886 
887 	g_topology_assert();
888 
889 	if (sc == NULL)
890 		return (ENXIO);
891 
892 	pp = sc->sc_provider;
893 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
894 		if (force) {
895 			G_STRIPE_DEBUG(0, "Device %s is still open, so it "
896 			    "can't be definitely removed.", pp->name);
897 		} else {
898 			G_STRIPE_DEBUG(1,
899 			    "Device %s is still open (r%dw%de%d).", pp->name,
900 			    pp->acr, pp->acw, pp->ace);
901 			return (EBUSY);
902 		}
903 	}
904 
905 	gp = sc->sc_geom;
906 	LIST_FOREACH_SAFE(cp, &gp->consumer, consumer, cp1) {
907 		g_stripe_remove_disk(cp);
908 		if (cp1 == NULL)
909 			return (0);	/* Recursion happened. */
910 	}
911 	if (!LIST_EMPTY(&gp->consumer))
912 		return (EINPROGRESS);
913 
914 	gp->softc = NULL;
915 	KASSERT(sc->sc_provider == NULL, ("Provider still exists? (device=%s)",
916 	    gp->name));
917 	free(sc->sc_disks, M_STRIPE);
918 	mtx_destroy(&sc->sc_lock);
919 	free(sc, M_STRIPE);
920 	G_STRIPE_DEBUG(0, "Device %s destroyed.", gp->name);
921 	g_wither_geom(gp, ENXIO);
922 	return (0);
923 }
924 
925 static int
926 g_stripe_destroy_geom(struct gctl_req *req __unused,
927     struct g_class *mp __unused, struct g_geom *gp)
928 {
929 	struct g_stripe_softc *sc;
930 
931 	sc = gp->softc;
932 	return (g_stripe_destroy(sc, 0));
933 }
934 
935 static struct g_geom *
936 g_stripe_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
937 {
938 	struct g_stripe_metadata md;
939 	struct g_stripe_softc *sc;
940 	struct g_consumer *cp;
941 	struct g_geom *gp;
942 	int error;
943 
944 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
945 	g_topology_assert();
946 
947 	/* Skip providers that are already open for writing. */
948 	if (pp->acw > 0)
949 		return (NULL);
950 
951 	G_STRIPE_DEBUG(3, "Tasting %s.", pp->name);
952 
953 	gp = g_new_geomf(mp, "stripe:taste");
954 	gp->start = g_stripe_start;
955 	gp->access = g_stripe_access;
956 	gp->orphan = g_stripe_orphan;
957 	cp = g_new_consumer(gp);
958 	g_attach(cp, pp);
959 	error = g_stripe_read_metadata(cp, &md);
960 	g_detach(cp);
961 	g_destroy_consumer(cp);
962 	g_destroy_geom(gp);
963 	if (error != 0)
964 		return (NULL);
965 	gp = NULL;
966 
967 	if (strcmp(md.md_magic, G_STRIPE_MAGIC) != 0)
968 		return (NULL);
969 	if (md.md_version > G_STRIPE_VERSION) {
970 		printf("geom_stripe.ko module is too old to handle %s.\n",
971 		    pp->name);
972 		return (NULL);
973 	}
974 	/*
975 	 * Backward compatibility:
976 	 */
977 	/* There was no md_provider field in earlier versions of metadata. */
978 	if (md.md_version < 2)
979 		bzero(md.md_provider, sizeof(md.md_provider));
980 	/* There was no md_provsize field in earlier versions of metadata. */
981 	if (md.md_version < 3)
982 		md.md_provsize = pp->mediasize;
983 
984 	if (md.md_provider[0] != '\0' &&
985 	    !g_compare_names(md.md_provider, pp->name))
986 		return (NULL);
987 	if (md.md_provsize != pp->mediasize)
988 		return (NULL);
989 
990 	/*
991 	 * Let's check if device already exists.
992 	 */
993 	sc = NULL;
994 	LIST_FOREACH(gp, &mp->geom, geom) {
995 		sc = gp->softc;
996 		if (sc == NULL)
997 			continue;
998 		if (sc->sc_type != G_STRIPE_TYPE_AUTOMATIC)
999 			continue;
1000 		if (strcmp(md.md_name, sc->sc_name) != 0)
1001 			continue;
1002 		if (md.md_id != sc->sc_id)
1003 			continue;
1004 		break;
1005 	}
1006 	if (gp != NULL) {
1007 		G_STRIPE_DEBUG(1, "Adding disk %s to %s.", pp->name, gp->name);
1008 		error = g_stripe_add_disk(sc, pp, md.md_no);
1009 		if (error != 0) {
1010 			G_STRIPE_DEBUG(0,
1011 			    "Cannot add disk %s to %s (error=%d).", pp->name,
1012 			    gp->name, error);
1013 			return (NULL);
1014 		}
1015 	} else {
1016 		gp = g_stripe_create(mp, &md, G_STRIPE_TYPE_AUTOMATIC);
1017 		if (gp == NULL) {
1018 			G_STRIPE_DEBUG(0, "Cannot create device %s.",
1019 			    md.md_name);
1020 			return (NULL);
1021 		}
1022 		sc = gp->softc;
1023 		G_STRIPE_DEBUG(1, "Adding disk %s to %s.", pp->name, gp->name);
1024 		error = g_stripe_add_disk(sc, pp, md.md_no);
1025 		if (error != 0) {
1026 			G_STRIPE_DEBUG(0,
1027 			    "Cannot add disk %s to %s (error=%d).", pp->name,
1028 			    gp->name, error);
1029 			g_stripe_destroy(sc, 1);
1030 			return (NULL);
1031 		}
1032 	}
1033 
1034 	return (gp);
1035 }
1036 
1037 static void
1038 g_stripe_ctl_create(struct gctl_req *req, struct g_class *mp)
1039 {
1040 	u_int attached, no;
1041 	struct g_stripe_metadata md;
1042 	struct g_provider *pp;
1043 	struct g_stripe_softc *sc;
1044 	struct g_geom *gp;
1045 	struct sbuf *sb;
1046 	intmax_t *stripesize;
1047 	const char *name;
1048 	char param[16];
1049 	int *nargs;
1050 
1051 	g_topology_assert();
1052 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
1053 	if (nargs == NULL) {
1054 		gctl_error(req, "No '%s' argument.", "nargs");
1055 		return;
1056 	}
1057 	if (*nargs <= 2) {
1058 		gctl_error(req, "Too few arguments.");
1059 		return;
1060 	}
1061 
1062 	strlcpy(md.md_magic, G_STRIPE_MAGIC, sizeof(md.md_magic));
1063 	md.md_version = G_STRIPE_VERSION;
1064 	name = gctl_get_asciiparam(req, "arg0");
1065 	if (name == NULL) {
1066 		gctl_error(req, "No 'arg%u' argument.", 0);
1067 		return;
1068 	}
1069 	strlcpy(md.md_name, name, sizeof(md.md_name));
1070 	md.md_id = arc4random();
1071 	md.md_no = 0;
1072 	md.md_all = *nargs - 1;
1073 	stripesize = gctl_get_paraml(req, "stripesize", sizeof(*stripesize));
1074 	if (stripesize == NULL) {
1075 		gctl_error(req, "No '%s' argument.", "stripesize");
1076 		return;
1077 	}
1078 	md.md_stripesize = *stripesize;
1079 	bzero(md.md_provider, sizeof(md.md_provider));
1080 	/* This field is not important here. */
1081 	md.md_provsize = 0;
1082 
1083 	/* Check all providers are valid */
1084 	for (no = 1; no < *nargs; no++) {
1085 		snprintf(param, sizeof(param), "arg%u", no);
1086 		name = gctl_get_asciiparam(req, param);
1087 		if (name == NULL) {
1088 			gctl_error(req, "No 'arg%u' argument.", no);
1089 			return;
1090 		}
1091 		if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
1092 			name += strlen("/dev/");
1093 		pp = g_provider_by_name(name);
1094 		if (pp == NULL) {
1095 			G_STRIPE_DEBUG(1, "Disk %s is invalid.", name);
1096 			gctl_error(req, "Disk %s is invalid.", name);
1097 			return;
1098 		}
1099 	}
1100 
1101 	gp = g_stripe_create(mp, &md, G_STRIPE_TYPE_MANUAL);
1102 	if (gp == NULL) {
1103 		gctl_error(req, "Can't configure %s.", md.md_name);
1104 		return;
1105 	}
1106 
1107 	sc = gp->softc;
1108 	sb = sbuf_new_auto();
1109 	sbuf_printf(sb, "Can't attach disk(s) to %s:", gp->name);
1110 	for (attached = 0, no = 1; no < *nargs; no++) {
1111 		snprintf(param, sizeof(param), "arg%u", no);
1112 		name = gctl_get_asciiparam(req, param);
1113 		if (name == NULL) {
1114 			gctl_error(req, "No 'arg%u' argument.", no);
1115 			continue;
1116 		}
1117 		if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
1118 			name += strlen("/dev/");
1119 		pp = g_provider_by_name(name);
1120 		KASSERT(pp != NULL, ("Provider %s disappear?!", name));
1121 		if (g_stripe_add_disk(sc, pp, no - 1) != 0) {
1122 			G_STRIPE_DEBUG(1, "Disk %u (%s) not attached to %s.",
1123 			    no, pp->name, gp->name);
1124 			sbuf_printf(sb, " %s", pp->name);
1125 			continue;
1126 		}
1127 		attached++;
1128 	}
1129 	sbuf_finish(sb);
1130 	if (md.md_all != attached) {
1131 		g_stripe_destroy(gp->softc, 1);
1132 		gctl_error(req, "%s", sbuf_data(sb));
1133 	}
1134 	sbuf_delete(sb);
1135 }
1136 
1137 static struct g_stripe_softc *
1138 g_stripe_find_device(struct g_class *mp, const char *name)
1139 {
1140 	struct g_stripe_softc *sc;
1141 	struct g_geom *gp;
1142 
1143 	LIST_FOREACH(gp, &mp->geom, geom) {
1144 		sc = gp->softc;
1145 		if (sc == NULL)
1146 			continue;
1147 		if (strcmp(sc->sc_name, name) == 0)
1148 			return (sc);
1149 	}
1150 	return (NULL);
1151 }
1152 
1153 static void
1154 g_stripe_ctl_destroy(struct gctl_req *req, struct g_class *mp)
1155 {
1156 	struct g_stripe_softc *sc;
1157 	int *force, *nargs, error;
1158 	const char *name;
1159 	char param[16];
1160 	u_int i;
1161 
1162 	g_topology_assert();
1163 
1164 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
1165 	if (nargs == NULL) {
1166 		gctl_error(req, "No '%s' argument.", "nargs");
1167 		return;
1168 	}
1169 	if (*nargs <= 0) {
1170 		gctl_error(req, "Missing device(s).");
1171 		return;
1172 	}
1173 	force = gctl_get_paraml(req, "force", sizeof(*force));
1174 	if (force == NULL) {
1175 		gctl_error(req, "No '%s' argument.", "force");
1176 		return;
1177 	}
1178 
1179 	for (i = 0; i < (u_int)*nargs; i++) {
1180 		snprintf(param, sizeof(param), "arg%u", i);
1181 		name = gctl_get_asciiparam(req, param);
1182 		if (name == NULL) {
1183 			gctl_error(req, "No 'arg%u' argument.", i);
1184 			return;
1185 		}
1186 		sc = g_stripe_find_device(mp, name);
1187 		if (sc == NULL) {
1188 			gctl_error(req, "No such device: %s.", name);
1189 			return;
1190 		}
1191 		error = g_stripe_destroy(sc, *force);
1192 		if (error != 0) {
1193 			gctl_error(req, "Cannot destroy device %s (error=%d).",
1194 			    sc->sc_name, error);
1195 			return;
1196 		}
1197 	}
1198 }
1199 
1200 static void
1201 g_stripe_config(struct gctl_req *req, struct g_class *mp, const char *verb)
1202 {
1203 	uint32_t *version;
1204 
1205 	g_topology_assert();
1206 
1207 	version = gctl_get_paraml(req, "version", sizeof(*version));
1208 	if (version == NULL) {
1209 		gctl_error(req, "No '%s' argument.", "version");
1210 		return;
1211 	}
1212 	if (*version != G_STRIPE_VERSION) {
1213 		gctl_error(req, "Userland and kernel parts are out of sync.");
1214 		return;
1215 	}
1216 
1217 	if (strcmp(verb, "create") == 0) {
1218 		g_stripe_ctl_create(req, mp);
1219 		return;
1220 	} else if (strcmp(verb, "destroy") == 0 ||
1221 	    strcmp(verb, "stop") == 0) {
1222 		g_stripe_ctl_destroy(req, mp);
1223 		return;
1224 	}
1225 
1226 	gctl_error(req, "Unknown verb.");
1227 }
1228 
1229 static void
1230 g_stripe_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
1231     struct g_consumer *cp, struct g_provider *pp)
1232 {
1233 	struct g_stripe_softc *sc;
1234 
1235 	sc = gp->softc;
1236 	if (sc == NULL)
1237 		return;
1238 	if (pp != NULL) {
1239 		/* Nothing here. */
1240 	} else if (cp != NULL) {
1241 		sbuf_printf(sb, "%s<Number>%u</Number>\n", indent,
1242 		    (u_int)cp->index);
1243 	} else {
1244 		sbuf_printf(sb, "%s<ID>%u</ID>\n", indent, (u_int)sc->sc_id);
1245 		sbuf_printf(sb, "%s<Stripesize>%u</Stripesize>\n", indent,
1246 		    (u_int)sc->sc_stripesize);
1247 		sbuf_printf(sb, "%s<Type>", indent);
1248 		switch (sc->sc_type) {
1249 		case G_STRIPE_TYPE_AUTOMATIC:
1250 			sbuf_printf(sb, "AUTOMATIC");
1251 			break;
1252 		case G_STRIPE_TYPE_MANUAL:
1253 			sbuf_printf(sb, "MANUAL");
1254 			break;
1255 		default:
1256 			sbuf_printf(sb, "UNKNOWN");
1257 			break;
1258 		}
1259 		sbuf_printf(sb, "</Type>\n");
1260 		sbuf_printf(sb, "%s<Status>Total=%u, Online=%u</Status>\n",
1261 		    indent, sc->sc_ndisks, g_stripe_nvalid(sc));
1262 		sbuf_printf(sb, "%s<State>", indent);
1263 		if (sc->sc_provider != NULL && sc->sc_provider->error == 0)
1264 			sbuf_printf(sb, "UP");
1265 		else
1266 			sbuf_printf(sb, "DOWN");
1267 		sbuf_printf(sb, "</State>\n");
1268 	}
1269 }
1270 
1271 DECLARE_GEOM_CLASS(g_stripe_class, g_stripe);
1272