xref: /freebsd/sys/geom/stripe/g_stripe.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
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 		G_STRIPE_DEBUG(0, "Device %s deactivated.",
175 		    sc->sc_provider->name);
176 		g_wither_provider(sc->sc_provider, ENXIO);
177 		sc->sc_provider = NULL;
178 	}
179 
180 	if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
181 		return;
182 	sc->sc_disks[cp->index] = NULL;
183 	cp->index = 0;
184 	g_detach(cp);
185 	g_destroy_consumer(cp);
186 	/* If there are no valid disks anymore, remove device. */
187 	if (LIST_EMPTY(&sc->sc_geom->consumer))
188 		g_stripe_destroy(sc, 1);
189 }
190 
191 static void
192 g_stripe_orphan(struct g_consumer *cp)
193 {
194 	struct g_stripe_softc *sc;
195 	struct g_geom *gp;
196 
197 	g_topology_assert();
198 	gp = cp->geom;
199 	sc = gp->softc;
200 	if (sc == NULL)
201 		return;
202 
203 	g_stripe_remove_disk(cp);
204 }
205 
206 static int
207 g_stripe_access(struct g_provider *pp, int dr, int dw, int de)
208 {
209 	struct g_consumer *cp1, *cp2, *tmp;
210 	struct g_stripe_softc *sc;
211 	struct g_geom *gp;
212 	int error;
213 
214 	g_topology_assert();
215 	gp = pp->geom;
216 	sc = gp->softc;
217 	KASSERT(sc != NULL, ("NULL sc in %s.", __func__));
218 
219 	/* On first open, grab an extra "exclusive" bit */
220 	if (pp->acr == 0 && pp->acw == 0 && pp->ace == 0)
221 		de++;
222 	/* ... and let go of it on last close */
223 	if ((pp->acr + dr) == 0 && (pp->acw + dw) == 0 && (pp->ace + de) == 0)
224 		de--;
225 
226 	LIST_FOREACH_SAFE(cp1, &gp->consumer, consumer, tmp) {
227 		error = g_access(cp1, dr, dw, de);
228 		if (error != 0)
229 			goto fail;
230 		if (cp1->acr == 0 && cp1->acw == 0 && cp1->ace == 0 &&
231 		    cp1->private != NULL) {
232 			g_stripe_remove_disk(cp1); /* May destroy geom. */
233 		}
234 	}
235 	return (0);
236 
237 fail:
238 	LIST_FOREACH(cp2, &gp->consumer, consumer) {
239 		if (cp1 == cp2)
240 			break;
241 		g_access(cp2, -dr, -dw, -de);
242 	}
243 	return (error);
244 }
245 
246 static void
247 g_stripe_copy(struct g_stripe_softc *sc, char *src, char *dst, off_t offset,
248     off_t length, int mode)
249 {
250 	u_int stripesize;
251 	size_t len;
252 
253 	stripesize = sc->sc_stripesize;
254 	len = (size_t)(stripesize - (offset & (stripesize - 1)));
255 	do {
256 		bcopy(src, dst, len);
257 		if (mode) {
258 			dst += len + stripesize * (sc->sc_ndisks - 1);
259 			src += len;
260 		} else {
261 			dst += len;
262 			src += len + stripesize * (sc->sc_ndisks - 1);
263 		}
264 		length -= len;
265 		KASSERT(length >= 0,
266 		    ("Length < 0 (stripesize=%zu, offset=%jd, length=%jd).",
267 		    (size_t)stripesize, (intmax_t)offset, (intmax_t)length));
268 		if (length > stripesize)
269 			len = stripesize;
270 		else
271 			len = length;
272 	} while (length > 0);
273 }
274 
275 static void
276 g_stripe_done(struct bio *bp)
277 {
278 	struct g_stripe_softc *sc;
279 	struct bio *pbp;
280 
281 	pbp = bp->bio_parent;
282 	sc = pbp->bio_to->geom->softc;
283 	if (bp->bio_cmd == BIO_READ && bp->bio_caller1 != NULL) {
284 		g_stripe_copy(sc, bp->bio_data, bp->bio_caller1, bp->bio_offset,
285 		    bp->bio_length, 1);
286 		bp->bio_data = bp->bio_caller1;
287 		bp->bio_caller1 = NULL;
288 	}
289 	mtx_lock(&sc->sc_lock);
290 	if (pbp->bio_error == 0)
291 		pbp->bio_error = bp->bio_error;
292 	pbp->bio_completed += bp->bio_completed;
293 	pbp->bio_inbed++;
294 	if (pbp->bio_children == pbp->bio_inbed) {
295 		mtx_unlock(&sc->sc_lock);
296 		if (pbp->bio_driver1 != NULL)
297 			uma_zfree(g_stripe_zone, pbp->bio_driver1);
298 		g_io_deliver(pbp, pbp->bio_error);
299 	} else
300 		mtx_unlock(&sc->sc_lock);
301 	g_destroy_bio(bp);
302 }
303 
304 static int
305 g_stripe_start_fast(struct bio *bp, u_int no, off_t offset, off_t length)
306 {
307 	TAILQ_HEAD(, bio) queue = TAILQ_HEAD_INITIALIZER(queue);
308 	u_int nparts = 0, stripesize;
309 	struct g_stripe_softc *sc;
310 	char *addr, *data = NULL;
311 	struct bio *cbp;
312 	int error;
313 
314 	sc = bp->bio_to->geom->softc;
315 
316 	addr = bp->bio_data;
317 	stripesize = sc->sc_stripesize;
318 
319 	cbp = g_clone_bio(bp);
320 	if (cbp == NULL) {
321 		error = ENOMEM;
322 		goto failure;
323 	}
324 	TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
325 	nparts++;
326 	/*
327 	 * Fill in the component buf structure.
328 	 */
329 	cbp->bio_done = g_stripe_done;
330 	cbp->bio_offset = offset;
331 	cbp->bio_data = addr;
332 	cbp->bio_caller1 = NULL;
333 	cbp->bio_length = length;
334 	cbp->bio_caller2 = sc->sc_disks[no];
335 
336 	/* offset -= offset % stripesize; */
337 	offset -= offset & (stripesize - 1);
338 	addr += length;
339 	length = bp->bio_length - length;
340 	for (no++; length > 0; no++, length -= stripesize, addr += stripesize) {
341 		if (no > sc->sc_ndisks - 1) {
342 			no = 0;
343 			offset += stripesize;
344 		}
345 		if (nparts >= sc->sc_ndisks) {
346 			cbp = TAILQ_NEXT(cbp, bio_queue);
347 			if (cbp == NULL)
348 				cbp = TAILQ_FIRST(&queue);
349 			nparts++;
350 			/*
351 			 * Update bio structure.
352 			 */
353 			/*
354 			 * MIN() is in case when
355 			 * (bp->bio_length % sc->sc_stripesize) != 0.
356 			 */
357 			cbp->bio_length += MIN(stripesize, length);
358 			if (cbp->bio_caller1 == NULL) {
359 				cbp->bio_caller1 = cbp->bio_data;
360 				cbp->bio_data = NULL;
361 				if (data == NULL) {
362 					data = uma_zalloc(g_stripe_zone,
363 					    M_NOWAIT);
364 					if (data == NULL) {
365 						error = ENOMEM;
366 						goto failure;
367 					}
368 				}
369 			}
370 		} else {
371 			cbp = g_clone_bio(bp);
372 			if (cbp == NULL) {
373 				error = ENOMEM;
374 				goto failure;
375 			}
376 			TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
377 			nparts++;
378 			/*
379 			 * Fill in the component buf structure.
380 			 */
381 			cbp->bio_done = g_stripe_done;
382 			cbp->bio_offset = offset;
383 			cbp->bio_data = addr;
384 			cbp->bio_caller1 = NULL;
385 			/*
386 			 * MIN() is in case when
387 			 * (bp->bio_length % sc->sc_stripesize) != 0.
388 			 */
389 			cbp->bio_length = MIN(stripesize, length);
390 			cbp->bio_caller2 = sc->sc_disks[no];
391 		}
392 	}
393 	if (data != NULL)
394 		bp->bio_driver1 = data;
395 	/*
396 	 * Fire off all allocated requests!
397 	 */
398 	while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
399 		struct g_consumer *cp;
400 
401 		TAILQ_REMOVE(&queue, cbp, bio_queue);
402 		cp = cbp->bio_caller2;
403 		cbp->bio_caller2 = NULL;
404 		cbp->bio_to = cp->provider;
405 		if (cbp->bio_caller1 != NULL) {
406 			cbp->bio_data = data;
407 			if (bp->bio_cmd == BIO_WRITE) {
408 				g_stripe_copy(sc, cbp->bio_caller1, data,
409 				    cbp->bio_offset, cbp->bio_length, 0);
410 			}
411 			data += cbp->bio_length;
412 		}
413 		G_STRIPE_LOGREQ(cbp, "Sending request.");
414 		g_io_request(cbp, cp);
415 	}
416 	return (0);
417 failure:
418 	if (data != NULL)
419 		uma_zfree(g_stripe_zone, data);
420 	while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
421 		TAILQ_REMOVE(&queue, cbp, bio_queue);
422 		if (cbp->bio_caller1 != NULL) {
423 			cbp->bio_data = cbp->bio_caller1;
424 			cbp->bio_caller1 = NULL;
425 		}
426 		bp->bio_children--;
427 		g_destroy_bio(cbp);
428 	}
429 	return (error);
430 }
431 
432 static int
433 g_stripe_start_economic(struct bio *bp, u_int no, off_t offset, off_t length)
434 {
435 	TAILQ_HEAD(, bio) queue = TAILQ_HEAD_INITIALIZER(queue);
436 	struct g_stripe_softc *sc;
437 	uint32_t stripesize;
438 	struct bio *cbp;
439 	char *addr;
440 	int error;
441 
442 	sc = bp->bio_to->geom->softc;
443 
444 	stripesize = sc->sc_stripesize;
445 
446 	cbp = g_clone_bio(bp);
447 	if (cbp == NULL) {
448 		error = ENOMEM;
449 		goto failure;
450 	}
451 	TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
452 	/*
453 	 * Fill in the component buf structure.
454 	 */
455 	if (bp->bio_length == length)
456 		cbp->bio_done = g_std_done;	/* Optimized lockless case. */
457 	else
458 		cbp->bio_done = g_stripe_done;
459 	cbp->bio_offset = offset;
460 	cbp->bio_length = length;
461 	if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
462 		bp->bio_ma_n = round_page(bp->bio_ma_offset +
463 		    bp->bio_length) / PAGE_SIZE;
464 		addr = NULL;
465 	} else
466 		addr = bp->bio_data;
467 	cbp->bio_caller2 = sc->sc_disks[no];
468 
469 	/* offset -= offset % stripesize; */
470 	offset -= offset & (stripesize - 1);
471 	if (bp->bio_cmd != BIO_DELETE)
472 		addr += length;
473 	length = bp->bio_length - length;
474 	for (no++; length > 0; no++, length -= stripesize) {
475 		if (no > sc->sc_ndisks - 1) {
476 			no = 0;
477 			offset += stripesize;
478 		}
479 		cbp = g_clone_bio(bp);
480 		if (cbp == NULL) {
481 			error = ENOMEM;
482 			goto failure;
483 		}
484 		TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
485 
486 		/*
487 		 * Fill in the component buf structure.
488 		 */
489 		cbp->bio_done = g_stripe_done;
490 		cbp->bio_offset = offset;
491 		/*
492 		 * MIN() is in case when
493 		 * (bp->bio_length % sc->sc_stripesize) != 0.
494 		 */
495 		cbp->bio_length = MIN(stripesize, length);
496 		if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
497 			cbp->bio_ma_offset += (uintptr_t)addr;
498 			cbp->bio_ma += cbp->bio_ma_offset / PAGE_SIZE;
499 			cbp->bio_ma_offset %= PAGE_SIZE;
500 			cbp->bio_ma_n = round_page(cbp->bio_ma_offset +
501 			    cbp->bio_length) / PAGE_SIZE;
502 		} else
503 			cbp->bio_data = addr;
504 
505 		cbp->bio_caller2 = sc->sc_disks[no];
506 
507 		if (bp->bio_cmd != BIO_DELETE)
508 			addr += stripesize;
509 	}
510 	/*
511 	 * Fire off all allocated requests!
512 	 */
513 	while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
514 		struct g_consumer *cp;
515 
516 		TAILQ_REMOVE(&queue, cbp, bio_queue);
517 		cp = cbp->bio_caller2;
518 		cbp->bio_caller2 = NULL;
519 		cbp->bio_to = cp->provider;
520 		G_STRIPE_LOGREQ(cbp, "Sending request.");
521 		g_io_request(cbp, cp);
522 	}
523 	return (0);
524 failure:
525 	while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
526 		TAILQ_REMOVE(&queue, cbp, bio_queue);
527 		bp->bio_children--;
528 		g_destroy_bio(cbp);
529 	}
530 	return (error);
531 }
532 
533 static void
534 g_stripe_flush(struct g_stripe_softc *sc, struct bio *bp)
535 {
536 	struct bio_queue_head queue;
537 	struct g_consumer *cp;
538 	struct bio *cbp;
539 	u_int no;
540 
541 	bioq_init(&queue);
542 	for (no = 0; no < sc->sc_ndisks; no++) {
543 		cbp = g_clone_bio(bp);
544 		if (cbp == NULL) {
545 			for (cbp = bioq_first(&queue); cbp != NULL;
546 			    cbp = bioq_first(&queue)) {
547 				bioq_remove(&queue, cbp);
548 				g_destroy_bio(cbp);
549 			}
550 			if (bp->bio_error == 0)
551 				bp->bio_error = ENOMEM;
552 			g_io_deliver(bp, bp->bio_error);
553 			return;
554 		}
555 		bioq_insert_tail(&queue, cbp);
556 		cbp->bio_done = g_stripe_done;
557 		cbp->bio_caller2 = sc->sc_disks[no];
558 		cbp->bio_to = sc->sc_disks[no]->provider;
559 	}
560 	for (cbp = bioq_first(&queue); cbp != NULL; cbp = bioq_first(&queue)) {
561 		bioq_remove(&queue, cbp);
562 		G_STRIPE_LOGREQ(cbp, "Sending request.");
563 		cp = cbp->bio_caller2;
564 		cbp->bio_caller2 = NULL;
565 		g_io_request(cbp, cp);
566 	}
567 }
568 
569 static void
570 g_stripe_start(struct bio *bp)
571 {
572 	off_t offset, start, length, nstripe;
573 	struct g_stripe_softc *sc;
574 	u_int no, stripesize;
575 	int error, fast = 0;
576 
577 	sc = bp->bio_to->geom->softc;
578 	/*
579 	 * If sc == NULL, provider's error should be set and g_stripe_start()
580 	 * should not be called at all.
581 	 */
582 	KASSERT(sc != NULL,
583 	    ("Provider's error should be set (error=%d)(device=%s).",
584 	    bp->bio_to->error, bp->bio_to->name));
585 
586 	G_STRIPE_LOGREQ(bp, "Request received.");
587 
588 	switch (bp->bio_cmd) {
589 	case BIO_READ:
590 	case BIO_WRITE:
591 	case BIO_DELETE:
592 		break;
593 	case BIO_FLUSH:
594 		g_stripe_flush(sc, bp);
595 		return;
596 	case BIO_GETATTR:
597 		/* To which provider it should be delivered? */
598 	default:
599 		g_io_deliver(bp, EOPNOTSUPP);
600 		return;
601 	}
602 
603 	stripesize = sc->sc_stripesize;
604 
605 	/*
606 	 * Calculations are quite messy, but fast I hope.
607 	 */
608 
609 	/* Stripe number. */
610 	/* nstripe = bp->bio_offset / stripesize; */
611 	nstripe = bp->bio_offset >> (off_t)sc->sc_stripebits;
612 	/* Disk number. */
613 	no = nstripe % sc->sc_ndisks;
614 	/* Start position in stripe. */
615 	/* start = bp->bio_offset % stripesize; */
616 	start = bp->bio_offset & (stripesize - 1);
617 	/* Start position in disk. */
618 	/* offset = (nstripe / sc->sc_ndisks) * stripesize + start; */
619 	offset = ((nstripe / sc->sc_ndisks) << sc->sc_stripebits) + start;
620 	/* Length of data to operate. */
621 	length = MIN(bp->bio_length, stripesize - start);
622 
623 	/*
624 	 * Do use "fast" mode when:
625 	 * 1. "Fast" mode is ON.
626 	 * and
627 	 * 2. Request size is less than or equal to MAXPHYS,
628 	 *    which should always be true.
629 	 * and
630 	 * 3. Request size is bigger than stripesize * ndisks. If it isn't,
631 	 *    there will be no need to send more than one I/O request to
632 	 *    a provider, so there is nothing to optmize.
633 	 * and
634 	 * 4. Request is not unmapped.
635 	 * and
636 	 * 5. It is not a BIO_DELETE.
637 	 */
638 	if (g_stripe_fast && bp->bio_length <= MAXPHYS &&
639 	    bp->bio_length >= stripesize * sc->sc_ndisks &&
640 	    (bp->bio_flags & BIO_UNMAPPED) == 0 &&
641 	    bp->bio_cmd != BIO_DELETE) {
642 		fast = 1;
643 	}
644 	error = 0;
645 	if (fast) {
646 		error = g_stripe_start_fast(bp, no, offset, length);
647 		if (error != 0)
648 			g_stripe_fast_failed++;
649 	}
650 	/*
651 	 * Do use "economic" when:
652 	 * 1. "Economic" mode is ON.
653 	 * or
654 	 * 2. "Fast" mode failed. It can only fail if there is no memory.
655 	 */
656 	if (!fast || error != 0)
657 		error = g_stripe_start_economic(bp, no, offset, length);
658 	if (error != 0) {
659 		if (bp->bio_error == 0)
660 			bp->bio_error = error;
661 		g_io_deliver(bp, bp->bio_error);
662 	}
663 }
664 
665 static void
666 g_stripe_check_and_run(struct g_stripe_softc *sc)
667 {
668 	struct g_provider *dp;
669 	off_t mediasize, ms;
670 	u_int no, sectorsize = 0;
671 
672 	g_topology_assert();
673 	if (g_stripe_nvalid(sc) != sc->sc_ndisks)
674 		return;
675 
676 	sc->sc_provider = g_new_providerf(sc->sc_geom, "stripe/%s",
677 	    sc->sc_name);
678 	sc->sc_provider->flags |= G_PF_DIRECT_SEND | G_PF_DIRECT_RECEIVE;
679 	if (g_stripe_fast == 0)
680 		sc->sc_provider->flags |= G_PF_ACCEPT_UNMAPPED;
681 	/*
682 	 * Find the smallest disk.
683 	 */
684 	mediasize = sc->sc_disks[0]->provider->mediasize;
685 	if (sc->sc_type == G_STRIPE_TYPE_AUTOMATIC)
686 		mediasize -= sc->sc_disks[0]->provider->sectorsize;
687 	mediasize -= mediasize % sc->sc_stripesize;
688 	sectorsize = sc->sc_disks[0]->provider->sectorsize;
689 	for (no = 1; no < sc->sc_ndisks; no++) {
690 		dp = sc->sc_disks[no]->provider;
691 		ms = dp->mediasize;
692 		if (sc->sc_type == G_STRIPE_TYPE_AUTOMATIC)
693 			ms -= dp->sectorsize;
694 		ms -= ms % sc->sc_stripesize;
695 		if (ms < mediasize)
696 			mediasize = ms;
697 		sectorsize = lcm(sectorsize, dp->sectorsize);
698 
699 		/* A provider underneath us doesn't support unmapped */
700 		if ((dp->flags & G_PF_ACCEPT_UNMAPPED) == 0) {
701 			G_STRIPE_DEBUG(1, "Cancelling unmapped "
702 			    "because of %s.", dp->name);
703 			sc->sc_provider->flags &= ~G_PF_ACCEPT_UNMAPPED;
704 		}
705 	}
706 	sc->sc_provider->sectorsize = sectorsize;
707 	sc->sc_provider->mediasize = mediasize * sc->sc_ndisks;
708 	sc->sc_provider->stripesize = sc->sc_stripesize;
709 	sc->sc_provider->stripeoffset = 0;
710 	g_error_provider(sc->sc_provider, 0);
711 
712 	G_STRIPE_DEBUG(0, "Device %s activated.", sc->sc_provider->name);
713 }
714 
715 static int
716 g_stripe_read_metadata(struct g_consumer *cp, struct g_stripe_metadata *md)
717 {
718 	struct g_provider *pp;
719 	u_char *buf;
720 	int error;
721 
722 	g_topology_assert();
723 
724 	error = g_access(cp, 1, 0, 0);
725 	if (error != 0)
726 		return (error);
727 	pp = cp->provider;
728 	g_topology_unlock();
729 	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
730 	    &error);
731 	g_topology_lock();
732 	g_access(cp, -1, 0, 0);
733 	if (buf == NULL)
734 		return (error);
735 
736 	/* Decode metadata. */
737 	stripe_metadata_decode(buf, md);
738 	g_free(buf);
739 
740 	return (0);
741 }
742 
743 /*
744  * Add disk to given device.
745  */
746 static int
747 g_stripe_add_disk(struct g_stripe_softc *sc, struct g_provider *pp, u_int no)
748 {
749 	struct g_consumer *cp, *fcp;
750 	struct g_geom *gp;
751 	int error;
752 
753 	g_topology_assert();
754 	/* Metadata corrupted? */
755 	if (no >= sc->sc_ndisks)
756 		return (EINVAL);
757 
758 	/* Check if disk is not already attached. */
759 	if (sc->sc_disks[no] != NULL)
760 		return (EEXIST);
761 
762 	gp = sc->sc_geom;
763 	fcp = LIST_FIRST(&gp->consumer);
764 
765 	cp = g_new_consumer(gp);
766 	cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE;
767 	cp->private = NULL;
768 	cp->index = no;
769 	error = g_attach(cp, pp);
770 	if (error != 0) {
771 		g_destroy_consumer(cp);
772 		return (error);
773 	}
774 
775 	if (fcp != NULL && (fcp->acr > 0 || fcp->acw > 0 || fcp->ace > 0)) {
776 		error = g_access(cp, fcp->acr, fcp->acw, fcp->ace);
777 		if (error != 0) {
778 			g_detach(cp);
779 			g_destroy_consumer(cp);
780 			return (error);
781 		}
782 	}
783 	if (sc->sc_type == G_STRIPE_TYPE_AUTOMATIC) {
784 		struct g_stripe_metadata md;
785 
786 		/* Reread metadata. */
787 		error = g_stripe_read_metadata(cp, &md);
788 		if (error != 0)
789 			goto fail;
790 
791 		if (strcmp(md.md_magic, G_STRIPE_MAGIC) != 0 ||
792 		    strcmp(md.md_name, sc->sc_name) != 0 ||
793 		    md.md_id != sc->sc_id) {
794 			G_STRIPE_DEBUG(0, "Metadata on %s changed.", pp->name);
795 			goto fail;
796 		}
797 	}
798 
799 	sc->sc_disks[no] = cp;
800 	G_STRIPE_DEBUG(0, "Disk %s attached to %s.", pp->name, sc->sc_name);
801 	g_stripe_check_and_run(sc);
802 
803 	return (0);
804 fail:
805 	if (fcp != NULL && (fcp->acr > 0 || fcp->acw > 0 || fcp->ace > 0))
806 		g_access(cp, -fcp->acr, -fcp->acw, -fcp->ace);
807 	g_detach(cp);
808 	g_destroy_consumer(cp);
809 	return (error);
810 }
811 
812 static struct g_geom *
813 g_stripe_create(struct g_class *mp, const struct g_stripe_metadata *md,
814     u_int type)
815 {
816 	struct g_stripe_softc *sc;
817 	struct g_geom *gp;
818 	u_int no;
819 
820 	g_topology_assert();
821 	G_STRIPE_DEBUG(1, "Creating device %s (id=%u).", md->md_name,
822 	    md->md_id);
823 
824 	/* Two disks is minimum. */
825 	if (md->md_all < 2) {
826 		G_STRIPE_DEBUG(0, "Too few disks defined for %s.", md->md_name);
827 		return (NULL);
828 	}
829 #if 0
830 	/* Stripe size have to be grater than or equal to sector size. */
831 	if (md->md_stripesize < sectorsize) {
832 		G_STRIPE_DEBUG(0, "Invalid stripe size for %s.", md->md_name);
833 		return (NULL);
834 	}
835 #endif
836 	/* Stripe size have to be power of 2. */
837 	if (!powerof2(md->md_stripesize)) {
838 		G_STRIPE_DEBUG(0, "Invalid stripe size for %s.", md->md_name);
839 		return (NULL);
840 	}
841 
842 	/* Check for duplicate unit */
843 	LIST_FOREACH(gp, &mp->geom, geom) {
844 		sc = gp->softc;
845 		if (sc != NULL && strcmp(sc->sc_name, md->md_name) == 0) {
846 			G_STRIPE_DEBUG(0, "Device %s already configured.",
847 			    sc->sc_name);
848 			return (NULL);
849 		}
850 	}
851 	gp = g_new_geomf(mp, "%s", md->md_name);
852 	sc = malloc(sizeof(*sc), M_STRIPE, M_WAITOK | M_ZERO);
853 	gp->start = g_stripe_start;
854 	gp->spoiled = g_stripe_orphan;
855 	gp->orphan = g_stripe_orphan;
856 	gp->access = g_stripe_access;
857 	gp->dumpconf = g_stripe_dumpconf;
858 
859 	sc->sc_id = md->md_id;
860 	sc->sc_stripesize = md->md_stripesize;
861 	sc->sc_stripebits = bitcount32(sc->sc_stripesize - 1);
862 	sc->sc_ndisks = md->md_all;
863 	sc->sc_disks = malloc(sizeof(struct g_consumer *) * sc->sc_ndisks,
864 	    M_STRIPE, M_WAITOK | M_ZERO);
865 	for (no = 0; no < sc->sc_ndisks; no++)
866 		sc->sc_disks[no] = NULL;
867 	sc->sc_type = type;
868 	mtx_init(&sc->sc_lock, "gstripe lock", NULL, MTX_DEF);
869 
870 	gp->softc = sc;
871 	sc->sc_geom = gp;
872 	sc->sc_provider = NULL;
873 
874 	G_STRIPE_DEBUG(0, "Device %s created (id=%u).", sc->sc_name, sc->sc_id);
875 
876 	return (gp);
877 }
878 
879 static int
880 g_stripe_destroy(struct g_stripe_softc *sc, boolean_t force)
881 {
882 	struct g_provider *pp;
883 	struct g_consumer *cp, *cp1;
884 	struct g_geom *gp;
885 
886 	g_topology_assert();
887 
888 	if (sc == NULL)
889 		return (ENXIO);
890 
891 	pp = sc->sc_provider;
892 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
893 		if (force) {
894 			G_STRIPE_DEBUG(0, "Device %s is still open, so it "
895 			    "can't be definitely removed.", pp->name);
896 		} else {
897 			G_STRIPE_DEBUG(1,
898 			    "Device %s is still open (r%dw%de%d).", pp->name,
899 			    pp->acr, pp->acw, pp->ace);
900 			return (EBUSY);
901 		}
902 	}
903 
904 	gp = sc->sc_geom;
905 	LIST_FOREACH_SAFE(cp, &gp->consumer, consumer, cp1) {
906 		g_stripe_remove_disk(cp);
907 		if (cp1 == NULL)
908 			return (0);	/* Recursion happened. */
909 	}
910 	if (!LIST_EMPTY(&gp->consumer))
911 		return (EINPROGRESS);
912 
913 	gp->softc = NULL;
914 	KASSERT(sc->sc_provider == NULL, ("Provider still exists? (device=%s)",
915 	    gp->name));
916 	free(sc->sc_disks, M_STRIPE);
917 	mtx_destroy(&sc->sc_lock);
918 	free(sc, M_STRIPE);
919 	G_STRIPE_DEBUG(0, "Device %s destroyed.", gp->name);
920 	g_wither_geom(gp, ENXIO);
921 	return (0);
922 }
923 
924 static int
925 g_stripe_destroy_geom(struct gctl_req *req __unused,
926     struct g_class *mp __unused, struct g_geom *gp)
927 {
928 	struct g_stripe_softc *sc;
929 
930 	sc = gp->softc;
931 	return (g_stripe_destroy(sc, 0));
932 }
933 
934 static struct g_geom *
935 g_stripe_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
936 {
937 	struct g_stripe_metadata md;
938 	struct g_stripe_softc *sc;
939 	struct g_consumer *cp;
940 	struct g_geom *gp;
941 	int error;
942 
943 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
944 	g_topology_assert();
945 
946 	/* Skip providers that are already open for writing. */
947 	if (pp->acw > 0)
948 		return (NULL);
949 
950 	G_STRIPE_DEBUG(3, "Tasting %s.", pp->name);
951 
952 	gp = g_new_geomf(mp, "stripe:taste");
953 	gp->start = g_stripe_start;
954 	gp->access = g_stripe_access;
955 	gp->orphan = g_stripe_orphan;
956 	cp = g_new_consumer(gp);
957 	g_attach(cp, pp);
958 	error = g_stripe_read_metadata(cp, &md);
959 	g_detach(cp);
960 	g_destroy_consumer(cp);
961 	g_destroy_geom(gp);
962 	if (error != 0)
963 		return (NULL);
964 	gp = NULL;
965 
966 	if (strcmp(md.md_magic, G_STRIPE_MAGIC) != 0)
967 		return (NULL);
968 	if (md.md_version > G_STRIPE_VERSION) {
969 		printf("geom_stripe.ko module is too old to handle %s.\n",
970 		    pp->name);
971 		return (NULL);
972 	}
973 	/*
974 	 * Backward compatibility:
975 	 */
976 	/* There was no md_provider field in earlier versions of metadata. */
977 	if (md.md_version < 2)
978 		bzero(md.md_provider, sizeof(md.md_provider));
979 	/* There was no md_provsize field in earlier versions of metadata. */
980 	if (md.md_version < 3)
981 		md.md_provsize = pp->mediasize;
982 
983 	if (md.md_provider[0] != '\0' &&
984 	    !g_compare_names(md.md_provider, pp->name))
985 		return (NULL);
986 	if (md.md_provsize != pp->mediasize)
987 		return (NULL);
988 
989 	/*
990 	 * Let's check if device already exists.
991 	 */
992 	sc = NULL;
993 	LIST_FOREACH(gp, &mp->geom, geom) {
994 		sc = gp->softc;
995 		if (sc == NULL)
996 			continue;
997 		if (sc->sc_type != G_STRIPE_TYPE_AUTOMATIC)
998 			continue;
999 		if (strcmp(md.md_name, sc->sc_name) != 0)
1000 			continue;
1001 		if (md.md_id != sc->sc_id)
1002 			continue;
1003 		break;
1004 	}
1005 	if (gp != NULL) {
1006 		G_STRIPE_DEBUG(1, "Adding disk %s to %s.", pp->name, gp->name);
1007 		error = g_stripe_add_disk(sc, pp, md.md_no);
1008 		if (error != 0) {
1009 			G_STRIPE_DEBUG(0,
1010 			    "Cannot add disk %s to %s (error=%d).", pp->name,
1011 			    gp->name, error);
1012 			return (NULL);
1013 		}
1014 	} else {
1015 		gp = g_stripe_create(mp, &md, G_STRIPE_TYPE_AUTOMATIC);
1016 		if (gp == NULL) {
1017 			G_STRIPE_DEBUG(0, "Cannot create device %s.",
1018 			    md.md_name);
1019 			return (NULL);
1020 		}
1021 		sc = gp->softc;
1022 		G_STRIPE_DEBUG(1, "Adding disk %s to %s.", pp->name, gp->name);
1023 		error = g_stripe_add_disk(sc, pp, md.md_no);
1024 		if (error != 0) {
1025 			G_STRIPE_DEBUG(0,
1026 			    "Cannot add disk %s to %s (error=%d).", pp->name,
1027 			    gp->name, error);
1028 			g_stripe_destroy(sc, 1);
1029 			return (NULL);
1030 		}
1031 	}
1032 
1033 	return (gp);
1034 }
1035 
1036 static void
1037 g_stripe_ctl_create(struct gctl_req *req, struct g_class *mp)
1038 {
1039 	u_int attached, no;
1040 	struct g_stripe_metadata md;
1041 	struct g_provider *pp;
1042 	struct g_stripe_softc *sc;
1043 	struct g_geom *gp;
1044 	struct sbuf *sb;
1045 	intmax_t *stripesize;
1046 	const char *name;
1047 	char param[16];
1048 	int *nargs;
1049 
1050 	g_topology_assert();
1051 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
1052 	if (nargs == NULL) {
1053 		gctl_error(req, "No '%s' argument.", "nargs");
1054 		return;
1055 	}
1056 	if (*nargs <= 2) {
1057 		gctl_error(req, "Too few arguments.");
1058 		return;
1059 	}
1060 
1061 	strlcpy(md.md_magic, G_STRIPE_MAGIC, sizeof(md.md_magic));
1062 	md.md_version = G_STRIPE_VERSION;
1063 	name = gctl_get_asciiparam(req, "arg0");
1064 	if (name == NULL) {
1065 		gctl_error(req, "No 'arg%u' argument.", 0);
1066 		return;
1067 	}
1068 	strlcpy(md.md_name, name, sizeof(md.md_name));
1069 	md.md_id = arc4random();
1070 	md.md_no = 0;
1071 	md.md_all = *nargs - 1;
1072 	stripesize = gctl_get_paraml(req, "stripesize", sizeof(*stripesize));
1073 	if (stripesize == NULL) {
1074 		gctl_error(req, "No '%s' argument.", "stripesize");
1075 		return;
1076 	}
1077 	md.md_stripesize = *stripesize;
1078 	bzero(md.md_provider, sizeof(md.md_provider));
1079 	/* This field is not important here. */
1080 	md.md_provsize = 0;
1081 
1082 	/* Check all providers are valid */
1083 	for (no = 1; no < *nargs; no++) {
1084 		snprintf(param, sizeof(param), "arg%u", no);
1085 		name = gctl_get_asciiparam(req, param);
1086 		if (name == NULL) {
1087 			gctl_error(req, "No 'arg%u' argument.", no);
1088 			return;
1089 		}
1090 		if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
1091 			name += strlen("/dev/");
1092 		pp = g_provider_by_name(name);
1093 		if (pp == NULL) {
1094 			G_STRIPE_DEBUG(1, "Disk %s is invalid.", name);
1095 			gctl_error(req, "Disk %s is invalid.", name);
1096 			return;
1097 		}
1098 	}
1099 
1100 	gp = g_stripe_create(mp, &md, G_STRIPE_TYPE_MANUAL);
1101 	if (gp == NULL) {
1102 		gctl_error(req, "Can't configure %s.", md.md_name);
1103 		return;
1104 	}
1105 
1106 	sc = gp->softc;
1107 	sb = sbuf_new_auto();
1108 	sbuf_printf(sb, "Can't attach disk(s) to %s:", gp->name);
1109 	for (attached = 0, no = 1; no < *nargs; no++) {
1110 		snprintf(param, sizeof(param), "arg%u", no);
1111 		name = gctl_get_asciiparam(req, param);
1112 		if (name == NULL) {
1113 			gctl_error(req, "No 'arg%u' argument.", no);
1114 			continue;
1115 		}
1116 		if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
1117 			name += strlen("/dev/");
1118 		pp = g_provider_by_name(name);
1119 		KASSERT(pp != NULL, ("Provider %s disappear?!", name));
1120 		if (g_stripe_add_disk(sc, pp, no - 1) != 0) {
1121 			G_STRIPE_DEBUG(1, "Disk %u (%s) not attached to %s.",
1122 			    no, pp->name, gp->name);
1123 			sbuf_printf(sb, " %s", pp->name);
1124 			continue;
1125 		}
1126 		attached++;
1127 	}
1128 	sbuf_finish(sb);
1129 	if (md.md_all != attached) {
1130 		g_stripe_destroy(gp->softc, 1);
1131 		gctl_error(req, "%s", sbuf_data(sb));
1132 	}
1133 	sbuf_delete(sb);
1134 }
1135 
1136 static struct g_stripe_softc *
1137 g_stripe_find_device(struct g_class *mp, const char *name)
1138 {
1139 	struct g_stripe_softc *sc;
1140 	struct g_geom *gp;
1141 
1142 	LIST_FOREACH(gp, &mp->geom, geom) {
1143 		sc = gp->softc;
1144 		if (sc == NULL)
1145 			continue;
1146 		if (strcmp(sc->sc_name, name) == 0)
1147 			return (sc);
1148 	}
1149 	return (NULL);
1150 }
1151 
1152 static void
1153 g_stripe_ctl_destroy(struct gctl_req *req, struct g_class *mp)
1154 {
1155 	struct g_stripe_softc *sc;
1156 	int *force, *nargs, error;
1157 	const char *name;
1158 	char param[16];
1159 	u_int i;
1160 
1161 	g_topology_assert();
1162 
1163 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
1164 	if (nargs == NULL) {
1165 		gctl_error(req, "No '%s' argument.", "nargs");
1166 		return;
1167 	}
1168 	if (*nargs <= 0) {
1169 		gctl_error(req, "Missing device(s).");
1170 		return;
1171 	}
1172 	force = gctl_get_paraml(req, "force", sizeof(*force));
1173 	if (force == NULL) {
1174 		gctl_error(req, "No '%s' argument.", "force");
1175 		return;
1176 	}
1177 
1178 	for (i = 0; i < (u_int)*nargs; i++) {
1179 		snprintf(param, sizeof(param), "arg%u", i);
1180 		name = gctl_get_asciiparam(req, param);
1181 		if (name == NULL) {
1182 			gctl_error(req, "No 'arg%u' argument.", i);
1183 			return;
1184 		}
1185 		sc = g_stripe_find_device(mp, name);
1186 		if (sc == NULL) {
1187 			gctl_error(req, "No such device: %s.", name);
1188 			return;
1189 		}
1190 		error = g_stripe_destroy(sc, *force);
1191 		if (error != 0) {
1192 			gctl_error(req, "Cannot destroy device %s (error=%d).",
1193 			    sc->sc_name, error);
1194 			return;
1195 		}
1196 	}
1197 }
1198 
1199 static void
1200 g_stripe_config(struct gctl_req *req, struct g_class *mp, const char *verb)
1201 {
1202 	uint32_t *version;
1203 
1204 	g_topology_assert();
1205 
1206 	version = gctl_get_paraml(req, "version", sizeof(*version));
1207 	if (version == NULL) {
1208 		gctl_error(req, "No '%s' argument.", "version");
1209 		return;
1210 	}
1211 	if (*version != G_STRIPE_VERSION) {
1212 		gctl_error(req, "Userland and kernel parts are out of sync.");
1213 		return;
1214 	}
1215 
1216 	if (strcmp(verb, "create") == 0) {
1217 		g_stripe_ctl_create(req, mp);
1218 		return;
1219 	} else if (strcmp(verb, "destroy") == 0 ||
1220 	    strcmp(verb, "stop") == 0) {
1221 		g_stripe_ctl_destroy(req, mp);
1222 		return;
1223 	}
1224 
1225 	gctl_error(req, "Unknown verb.");
1226 }
1227 
1228 static void
1229 g_stripe_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
1230     struct g_consumer *cp, struct g_provider *pp)
1231 {
1232 	struct g_stripe_softc *sc;
1233 
1234 	sc = gp->softc;
1235 	if (sc == NULL)
1236 		return;
1237 	if (pp != NULL) {
1238 		/* Nothing here. */
1239 	} else if (cp != NULL) {
1240 		sbuf_printf(sb, "%s<Number>%u</Number>\n", indent,
1241 		    (u_int)cp->index);
1242 	} else {
1243 		sbuf_printf(sb, "%s<ID>%u</ID>\n", indent, (u_int)sc->sc_id);
1244 		sbuf_printf(sb, "%s<Stripesize>%u</Stripesize>\n", indent,
1245 		    (u_int)sc->sc_stripesize);
1246 		sbuf_printf(sb, "%s<Type>", indent);
1247 		switch (sc->sc_type) {
1248 		case G_STRIPE_TYPE_AUTOMATIC:
1249 			sbuf_printf(sb, "AUTOMATIC");
1250 			break;
1251 		case G_STRIPE_TYPE_MANUAL:
1252 			sbuf_printf(sb, "MANUAL");
1253 			break;
1254 		default:
1255 			sbuf_printf(sb, "UNKNOWN");
1256 			break;
1257 		}
1258 		sbuf_printf(sb, "</Type>\n");
1259 		sbuf_printf(sb, "%s<Status>Total=%u, Online=%u</Status>\n",
1260 		    indent, sc->sc_ndisks, g_stripe_nvalid(sc));
1261 		sbuf_printf(sb, "%s<State>", indent);
1262 		if (sc->sc_provider != NULL && sc->sc_provider->error == 0)
1263 			sbuf_printf(sb, "UP");
1264 		else
1265 			sbuf_printf(sb, "DOWN");
1266 		sbuf_printf(sb, "</State>\n");
1267 	}
1268 }
1269 
1270 DECLARE_GEOM_CLASS(g_stripe_class, g_stripe);
1271