xref: /freebsd/sys/geom/vinum/geom_vinum_plex.c (revision 9f23cbd6cae82fd77edfad7173432fa8dccd0a95)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2004, 2007 Lukas Ertl
5  * Copyright (c) 2007, 2009 Ulf Lilleengen
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/param.h>
34 #include <sys/bio.h>
35 #include <sys/lock.h>
36 #include <sys/malloc.h>
37 #include <sys/systm.h>
38 
39 #include <geom/geom.h>
40 #include <geom/geom_dbg.h>
41 #include <geom/vinum/geom_vinum_var.h>
42 #include <geom/vinum/geom_vinum_raid5.h>
43 #include <geom/vinum/geom_vinum.h>
44 
45 static int	gv_check_parity(struct gv_plex *, struct bio *,
46 		    struct gv_raid5_packet *);
47 static int	gv_normal_parity(struct gv_plex *, struct bio *,
48 		    struct gv_raid5_packet *);
49 static void	gv_plex_flush(struct gv_plex *);
50 static int	gv_plex_offset(struct gv_plex *, off_t, off_t, off_t *, off_t *,
51 		    int *, int);
52 static int 	gv_plex_normal_request(struct gv_plex *, struct bio *, off_t,
53 		    off_t,  caddr_t);
54 static void	gv_post_bio(struct gv_softc *, struct bio *);
55 
56 void
57 gv_plex_start(struct gv_plex *p, struct bio *bp)
58 {
59 	struct bio *cbp;
60 	struct gv_sd *s;
61 	struct gv_raid5_packet *wp;
62 	caddr_t addr;
63 	off_t bcount, boff, len;
64 
65 	bcount = bp->bio_length;
66 	addr = bp->bio_data;
67 	boff = bp->bio_offset;
68 
69 	/* Walk over the whole length of the request, we might split it up. */
70 	while (bcount > 0) {
71 		wp = NULL;
72 
73  		/*
74 		 * RAID5 plexes need special treatment, as a single request
75 		 * might involve several read/write sub-requests.
76  		 */
77 		if (p->org == GV_PLEX_RAID5) {
78 			wp = gv_raid5_start(p, bp, addr, boff, bcount);
79  			if (wp == NULL)
80  				return;
81 
82 			len = wp->length;
83 
84 			if (TAILQ_EMPTY(&wp->bits))
85 				g_free(wp);
86 			else if (wp->lockbase != -1)
87 				TAILQ_INSERT_TAIL(&p->packets, wp, list);
88 
89 		/*
90 		 * Requests to concatenated and striped plexes go straight
91 		 * through.
92 		 */
93 		} else {
94 			len = gv_plex_normal_request(p, bp, boff, bcount, addr);
95 		}
96 		if (len < 0)
97 			return;
98 
99 		bcount -= len;
100 		addr += len;
101 		boff += len;
102 	}
103 
104 	/*
105 	 * Fire off all sub-requests.  We get the correct consumer (== drive)
106 	 * to send each request to via the subdisk that was stored in
107 	 * cbp->bio_caller1.
108 	 */
109 	cbp = bioq_takefirst(p->bqueue);
110 	while (cbp != NULL) {
111 		/*
112 		 * RAID5 sub-requests need to come in correct order, otherwise
113 		 * we trip over the parity, as it might be overwritten by
114 		 * another sub-request.  We abuse cbp->bio_caller2 to mark
115 		 * potential overlap situations.
116 		 */
117 		if (cbp->bio_caller2 != NULL && gv_stripe_active(p, cbp)) {
118 			/* Park the bio on the waiting queue. */
119 			cbp->bio_pflags |= GV_BIO_ONHOLD;
120 			bioq_disksort(p->wqueue, cbp);
121 		} else {
122 			s = cbp->bio_caller1;
123 			g_io_request(cbp, s->drive_sc->consumer);
124 		}
125 		cbp = bioq_takefirst(p->bqueue);
126 	}
127 }
128 
129 static int
130 gv_plex_offset(struct gv_plex *p, off_t boff, off_t bcount, off_t *real_off,
131     off_t *real_len, int *sdno, int growing)
132 {
133 	struct gv_sd *s;
134 	int i, sdcount;
135 	off_t len_left, stripeend, stripeno, stripestart;
136 
137 	switch (p->org) {
138 	case GV_PLEX_CONCAT:
139 		/*
140 		 * Find the subdisk where this request starts.  The subdisks in
141 		 * this list must be ordered by plex_offset.
142 		 */
143 		i = 0;
144 		LIST_FOREACH(s, &p->subdisks, in_plex) {
145 			if (s->plex_offset <= boff &&
146 			    s->plex_offset + s->size > boff) {
147 				*sdno = i;
148 				break;
149 			}
150 			i++;
151 		}
152 		if (s == NULL || s->drive_sc == NULL)
153 			return (GV_ERR_NOTFOUND);
154 
155 		/* Calculate corresponding offsets on disk. */
156 		*real_off = boff - s->plex_offset;
157 		len_left = s->size - (*real_off);
158 		KASSERT(len_left >= 0, ("gv_plex_offset: len_left < 0"));
159 		*real_len = (bcount > len_left) ? len_left : bcount;
160 		break;
161 
162 	case GV_PLEX_STRIPED:
163 		/* The number of the stripe where the request starts. */
164 		stripeno = boff / p->stripesize;
165 		KASSERT(stripeno >= 0, ("gv_plex_offset: stripeno < 0"));
166 
167 		/* Take growing subdisks into account when calculating. */
168 		sdcount = gv_sdcount(p, (boff >= p->synced));
169 
170 		if (!(boff + bcount <= p->synced) &&
171 		    (p->flags & GV_PLEX_GROWING) &&
172 		    !growing)
173 			return (GV_ERR_ISBUSY);
174 		*sdno = stripeno % sdcount;
175 
176 		KASSERT(*sdno >= 0, ("gv_plex_offset: sdno < 0"));
177 		stripestart = (stripeno / sdcount) *
178 		    p->stripesize;
179 		KASSERT(stripestart >= 0, ("gv_plex_offset: stripestart < 0"));
180 		stripeend = stripestart + p->stripesize;
181 		*real_off = boff - (stripeno * p->stripesize) +
182 		    stripestart;
183 		len_left = stripeend - *real_off;
184 		KASSERT(len_left >= 0, ("gv_plex_offset: len_left < 0"));
185 
186 		*real_len = (bcount <= len_left) ? bcount : len_left;
187 		break;
188 
189 	default:
190 		return (GV_ERR_PLEXORG);
191 	}
192 	return (0);
193 }
194 
195 /*
196  * Prepare a normal plex request.
197  */
198 static int
199 gv_plex_normal_request(struct gv_plex *p, struct bio *bp, off_t boff,
200     off_t bcount,  caddr_t addr)
201 {
202 	struct gv_sd *s;
203 	struct bio *cbp;
204 	off_t real_len, real_off;
205 	int i, err, sdno;
206 
207 	s = NULL;
208 	sdno = -1;
209 	real_len = real_off = 0;
210 
211 	err = ENXIO;
212 
213 	if (p == NULL || LIST_EMPTY(&p->subdisks))
214 		goto bad;
215 
216 	err = gv_plex_offset(p, boff, bcount, &real_off,
217 	    &real_len, &sdno, (bp->bio_pflags & GV_BIO_GROW));
218 	/* If the request was blocked, put it into wait. */
219 	if (err == GV_ERR_ISBUSY) {
220 		bioq_disksort(p->rqueue, bp);
221 		return (-1); /* "Fail", and delay request. */
222 	}
223 	if (err) {
224 		err = ENXIO;
225 		goto bad;
226 	}
227 	err = ENXIO;
228 
229 	/* Find the right subdisk. */
230 	i = 0;
231 	LIST_FOREACH(s, &p->subdisks, in_plex) {
232 		if (i == sdno)
233 			break;
234 		i++;
235 	}
236 
237 	/* Subdisk not found. */
238 	if (s == NULL || s->drive_sc == NULL)
239 		goto bad;
240 
241 	/* Now check if we can handle the request on this subdisk. */
242 	switch (s->state) {
243 	case GV_SD_UP:
244 		/* If the subdisk is up, just continue. */
245 		break;
246 	case GV_SD_DOWN:
247 		if (bp->bio_pflags & GV_BIO_INTERNAL)
248 			G_VINUM_DEBUG(0, "subdisk must be in the stale state in"
249 			    " order to perform administrative requests");
250 		goto bad;
251 	case GV_SD_STALE:
252 		if (!(bp->bio_pflags & GV_BIO_SYNCREQ)) {
253 			G_VINUM_DEBUG(0, "subdisk stale, unable to perform "
254 			    "regular requests");
255 			goto bad;
256 		}
257 
258 		G_VINUM_DEBUG(1, "sd %s is initializing", s->name);
259 		gv_set_sd_state(s, GV_SD_INITIALIZING, GV_SETSTATE_FORCE);
260 		break;
261 	case GV_SD_INITIALIZING:
262 		if (bp->bio_cmd == BIO_READ)
263 			goto bad;
264 		break;
265 	default:
266 		/* All other subdisk states mean it's not accessible. */
267 		goto bad;
268 	}
269 
270 	/* Clone the bio and adjust the offsets and sizes. */
271 	cbp = g_clone_bio(bp);
272 	if (cbp == NULL) {
273 		err = ENOMEM;
274 		goto bad;
275 	}
276 	cbp->bio_offset = real_off + s->drive_offset;
277 	cbp->bio_length = real_len;
278 	cbp->bio_data = addr;
279 	cbp->bio_done = gv_done;
280 	cbp->bio_caller1 = s;
281 	s->drive_sc->active++;
282 
283 	/* Store the sub-requests now and let others issue them. */
284 	bioq_insert_tail(p->bqueue, cbp);
285 	return (real_len);
286 bad:
287 	G_VINUM_LOGREQ(0, bp, "plex request failed.");
288 	/* Building the sub-request failed. If internal BIO, do not deliver. */
289 	if (bp->bio_pflags & GV_BIO_INTERNAL) {
290 		if (bp->bio_pflags & GV_BIO_MALLOC)
291 			g_free(bp->bio_data);
292 		g_destroy_bio(bp);
293 		p->flags &= ~(GV_PLEX_SYNCING | GV_PLEX_REBUILDING |
294 		    GV_PLEX_GROWING);
295 		return (-1);
296 	}
297 	g_io_deliver(bp, err);
298 	return (-1);
299 }
300 
301 /*
302  * Handle a completed request to a striped or concatenated plex.
303  */
304 void
305 gv_plex_normal_done(struct gv_plex *p, struct bio *bp)
306 {
307 	struct bio *pbp;
308 
309 	pbp = bp->bio_parent;
310 	if (pbp->bio_error == 0)
311 		pbp->bio_error = bp->bio_error;
312 	g_destroy_bio(bp);
313 	pbp->bio_inbed++;
314 	if (pbp->bio_children == pbp->bio_inbed) {
315 		/* Just set it to length since multiple plexes will
316 		 * screw things up. */
317 		pbp->bio_completed = pbp->bio_length;
318 		if (pbp->bio_pflags & GV_BIO_SYNCREQ)
319 			gv_sync_complete(p, pbp);
320 		else if (pbp->bio_pflags & GV_BIO_GROW)
321 			gv_grow_complete(p, pbp);
322 		else
323 			g_io_deliver(pbp, pbp->bio_error);
324 	}
325 }
326 
327 /*
328  * Handle a completed request to a RAID-5 plex.
329  */
330 void
331 gv_plex_raid5_done(struct gv_plex *p, struct bio *bp)
332 {
333 	struct gv_softc *sc;
334 	struct bio *cbp, *pbp;
335 	struct gv_bioq *bq, *bq2;
336 	struct gv_raid5_packet *wp;
337 	off_t completed;
338 	int i;
339 
340 	completed = 0;
341 	sc = p->vinumconf;
342 	wp = bp->bio_caller2;
343 
344 	switch (bp->bio_parent->bio_cmd) {
345 	case BIO_READ:
346 		if (wp == NULL) {
347 			completed = bp->bio_completed;
348 			break;
349 		}
350 
351 		TAILQ_FOREACH_SAFE(bq, &wp->bits, queue, bq2) {
352 			if (bq->bp != bp)
353 				continue;
354 			TAILQ_REMOVE(&wp->bits, bq, queue);
355 			g_free(bq);
356 			for (i = 0; i < wp->length; i++)
357 				wp->data[i] ^= bp->bio_data[i];
358 			break;
359 		}
360 		if (TAILQ_EMPTY(&wp->bits)) {
361 			completed = wp->length;
362 			if (wp->lockbase != -1) {
363 				TAILQ_REMOVE(&p->packets, wp, list);
364 				/* Bring the waiting bios back into the game. */
365 				pbp = bioq_takefirst(p->wqueue);
366 				while (pbp != NULL) {
367 					gv_post_bio(sc, pbp);
368 					pbp = bioq_takefirst(p->wqueue);
369 				}
370 			}
371 			g_free(wp);
372 		}
373 
374 		break;
375 
376  	case BIO_WRITE:
377 		/* XXX can this ever happen? */
378 		if (wp == NULL) {
379 			completed = bp->bio_completed;
380 			break;
381 		}
382 
383 		/* Check if we need to handle parity data. */
384 		TAILQ_FOREACH_SAFE(bq, &wp->bits, queue, bq2) {
385 			if (bq->bp != bp)
386 				continue;
387 			TAILQ_REMOVE(&wp->bits, bq, queue);
388 			g_free(bq);
389 			cbp = wp->parity;
390 			if (cbp != NULL) {
391 				for (i = 0; i < wp->length; i++)
392 					cbp->bio_data[i] ^= bp->bio_data[i];
393 			}
394 			break;
395 		}
396 
397 		/* Handle parity data. */
398 		if (TAILQ_EMPTY(&wp->bits)) {
399 			if (bp->bio_parent->bio_pflags & GV_BIO_CHECK)
400 				i = gv_check_parity(p, bp, wp);
401 			else
402 				i = gv_normal_parity(p, bp, wp);
403 
404 			/* All of our sub-requests have finished. */
405 			if (i) {
406 				completed = wp->length;
407 				TAILQ_REMOVE(&p->packets, wp, list);
408 				/* Bring the waiting bios back into the game. */
409 				pbp = bioq_takefirst(p->wqueue);
410 				while (pbp != NULL) {
411 					gv_post_bio(sc, pbp);
412 					pbp = bioq_takefirst(p->wqueue);
413 				}
414 				g_free(wp);
415 			}
416 		}
417 
418 		break;
419 	}
420 
421 	pbp = bp->bio_parent;
422 	if (pbp->bio_error == 0)
423 		pbp->bio_error = bp->bio_error;
424 	pbp->bio_completed += completed;
425 
426 	/* When the original request is finished, we deliver it. */
427 	pbp->bio_inbed++;
428 	if (pbp->bio_inbed == pbp->bio_children) {
429 		/* Hand it over for checking or delivery. */
430 		if (pbp->bio_cmd == BIO_WRITE &&
431 		    (pbp->bio_pflags & GV_BIO_CHECK)) {
432 			gv_parity_complete(p, pbp);
433 		} else if (pbp->bio_cmd == BIO_WRITE &&
434 		    (pbp->bio_pflags & GV_BIO_REBUILD)) {
435 			gv_rebuild_complete(p, pbp);
436 		} else if (pbp->bio_pflags & GV_BIO_INIT) {
437 			gv_init_complete(p, pbp);
438 		} else if (pbp->bio_pflags & GV_BIO_SYNCREQ) {
439 			gv_sync_complete(p, pbp);
440 		} else if (pbp->bio_pflags & GV_BIO_GROW) {
441 			gv_grow_complete(p, pbp);
442 		} else {
443 			g_io_deliver(pbp, pbp->bio_error);
444 		}
445 	}
446 
447 	/* Clean up what we allocated. */
448 	if (bp->bio_cflags & GV_BIO_MALLOC)
449 		g_free(bp->bio_data);
450 	g_destroy_bio(bp);
451 }
452 
453 static int
454 gv_check_parity(struct gv_plex *p, struct bio *bp, struct gv_raid5_packet *wp)
455 {
456 	struct bio *pbp;
457 	struct gv_sd *s;
458 	int err, finished, i;
459 
460 	err = 0;
461 	finished = 1;
462 
463 	if (wp->waiting != NULL) {
464 		pbp = wp->waiting;
465 		wp->waiting = NULL;
466 		s = pbp->bio_caller1;
467 		g_io_request(pbp, s->drive_sc->consumer);
468 		finished = 0;
469 
470 	} else if (wp->parity != NULL) {
471 		pbp = wp->parity;
472 		wp->parity = NULL;
473 
474 		/* Check if the parity is correct. */
475 		for (i = 0; i < wp->length; i++) {
476 			if (bp->bio_data[i] != pbp->bio_data[i]) {
477 				err = 1;
478 				break;
479 			}
480 		}
481 
482 		/* The parity is not correct... */
483 		if (err) {
484 			bp->bio_parent->bio_error = EAGAIN;
485 
486 			/* ... but we rebuild it. */
487 			if (bp->bio_parent->bio_pflags & GV_BIO_PARITY) {
488 				s = pbp->bio_caller1;
489 				g_io_request(pbp, s->drive_sc->consumer);
490 				finished = 0;
491 			}
492 		}
493 
494 		/*
495 		 * Clean up the BIO we would have used for rebuilding the
496 		 * parity.
497 		 */
498 		if (finished) {
499 			bp->bio_parent->bio_inbed++;
500 			g_destroy_bio(pbp);
501 		}
502 	}
503 
504 	return (finished);
505 }
506 
507 static int
508 gv_normal_parity(struct gv_plex *p, struct bio *bp, struct gv_raid5_packet *wp)
509 {
510 	struct bio *cbp, *pbp;
511 	struct gv_sd *s;
512 	int finished, i;
513 
514 	finished = 1;
515 
516 	if (wp->waiting != NULL) {
517 		pbp = wp->waiting;
518 		wp->waiting = NULL;
519 		cbp = wp->parity;
520 		for (i = 0; i < wp->length; i++)
521 			cbp->bio_data[i] ^= pbp->bio_data[i];
522 		s = pbp->bio_caller1;
523 		g_io_request(pbp, s->drive_sc->consumer);
524 		finished = 0;
525 
526 	} else if (wp->parity != NULL) {
527 		cbp = wp->parity;
528 		wp->parity = NULL;
529 		s = cbp->bio_caller1;
530 		g_io_request(cbp, s->drive_sc->consumer);
531 		finished = 0;
532 	}
533 
534 	return (finished);
535 }
536 
537 /* Flush the queue with delayed requests. */
538 static void
539 gv_plex_flush(struct gv_plex *p)
540 {
541 	struct bio *bp;
542 
543 	bp = bioq_takefirst(p->rqueue);
544 	while (bp != NULL) {
545 		gv_plex_start(p, bp);
546 		bp = bioq_takefirst(p->rqueue);
547 	}
548 }
549 
550 static void
551 gv_post_bio(struct gv_softc *sc, struct bio *bp)
552 {
553 
554 	KASSERT(sc != NULL, ("NULL sc"));
555 	KASSERT(bp != NULL, ("NULL bp"));
556 	mtx_lock(&sc->bqueue_mtx);
557 	bioq_disksort(sc->bqueue_down, bp);
558 	wakeup(sc);
559 	mtx_unlock(&sc->bqueue_mtx);
560 }
561 
562 int
563 gv_sync_request(struct gv_plex *from, struct gv_plex *to, off_t offset,
564     off_t length, int type, caddr_t data)
565 {
566 	struct gv_softc *sc;
567 	struct bio *bp;
568 
569 	KASSERT(from != NULL, ("NULL from"));
570 	KASSERT(to != NULL, ("NULL to"));
571 	sc = from->vinumconf;
572 	KASSERT(sc != NULL, ("NULL sc"));
573 
574 	bp = g_new_bio();
575 	if (bp == NULL) {
576 		G_VINUM_DEBUG(0, "sync from '%s' failed at offset "
577 		    " %jd; out of memory", from->name, offset);
578 		return (ENOMEM);
579 	}
580 	bp->bio_length = length;
581 	bp->bio_done = NULL;
582 	bp->bio_pflags |= GV_BIO_SYNCREQ;
583 	bp->bio_offset = offset;
584 	bp->bio_caller1 = from;
585 	bp->bio_caller2 = to;
586 	bp->bio_cmd = type;
587 	if (data == NULL)
588 		data = g_malloc(length, M_WAITOK);
589 	bp->bio_pflags |= GV_BIO_MALLOC; /* Free on the next run. */
590 	bp->bio_data = data;
591 
592 	/* Send down next. */
593 	gv_post_bio(sc, bp);
594 	//gv_plex_start(from, bp);
595 	return (0);
596 }
597 
598 /*
599  * Handle a finished plex sync bio.
600  */
601 int
602 gv_sync_complete(struct gv_plex *to, struct bio *bp)
603 {
604 	struct gv_plex *from, *p;
605 	struct gv_sd *s;
606 	struct gv_volume *v;
607 	struct gv_softc *sc;
608 	off_t offset;
609 	int err;
610 
611 	g_topology_assert_not();
612 
613 	err = 0;
614 	KASSERT(to != NULL, ("NULL to"));
615 	KASSERT(bp != NULL, ("NULL bp"));
616 	from = bp->bio_caller2;
617 	KASSERT(from != NULL, ("NULL from"));
618 	v = to->vol_sc;
619 	KASSERT(v != NULL, ("NULL v"));
620 	sc = v->vinumconf;
621 	KASSERT(sc != NULL, ("NULL sc"));
622 
623 	/* If it was a read, write it. */
624 	if (bp->bio_cmd == BIO_READ) {
625 		err = gv_sync_request(from, to, bp->bio_offset, bp->bio_length,
626 	    	    BIO_WRITE, bp->bio_data);
627 	/* If it was a write, read the next one. */
628 	} else if (bp->bio_cmd == BIO_WRITE) {
629 		if (bp->bio_pflags & GV_BIO_MALLOC)
630 			g_free(bp->bio_data);
631 		to->synced += bp->bio_length;
632 		/* If we're finished, clean up. */
633 		if (bp->bio_offset + bp->bio_length >= from->size) {
634 			G_VINUM_DEBUG(1, "syncing of %s from %s completed",
635 			    to->name, from->name);
636 			/* Update our state. */
637 			LIST_FOREACH(s, &to->subdisks, in_plex)
638 				gv_set_sd_state(s, GV_SD_UP, 0);
639 			gv_update_plex_state(to);
640 			to->flags &= ~GV_PLEX_SYNCING;
641 			to->synced = 0;
642 			gv_post_event(sc, GV_EVENT_SAVE_CONFIG, sc, NULL, 0, 0);
643 		} else {
644 			offset = bp->bio_offset + bp->bio_length;
645 			err = gv_sync_request(from, to, offset,
646 			    MIN(bp->bio_length, from->size - offset),
647 			    BIO_READ, NULL);
648 		}
649 	}
650 	g_destroy_bio(bp);
651 	/* Clean up if there was an error. */
652 	if (err) {
653 		to->flags &= ~GV_PLEX_SYNCING;
654 		G_VINUM_DEBUG(0, "error syncing plexes: error code %d", err);
655 	}
656 
657 	/* Check if all plexes are synced, and lower refcounts. */
658 	g_topology_lock();
659 	LIST_FOREACH(p, &v->plexes, in_volume) {
660 		if (p->flags & GV_PLEX_SYNCING) {
661 			g_topology_unlock();
662 			return (-1);
663 		}
664 	}
665 	/* If we came here, all plexes are synced, and we're free. */
666 	gv_access(v->provider, -1, -1, 0);
667 	g_topology_unlock();
668 	G_VINUM_DEBUG(1, "plex sync completed");
669 	gv_volume_flush(v);
670 	return (0);
671 }
672 
673 /*
674  * Create a new bio struct for the next grow request.
675  */
676 int
677 gv_grow_request(struct gv_plex *p, off_t offset, off_t length, int type,
678     caddr_t data)
679 {
680 	struct gv_softc *sc;
681 	struct bio *bp;
682 
683 	KASSERT(p != NULL, ("gv_grow_request: NULL p"));
684 	sc = p->vinumconf;
685 	KASSERT(sc != NULL, ("gv_grow_request: NULL sc"));
686 
687 	bp = g_new_bio();
688 	if (bp == NULL) {
689 		G_VINUM_DEBUG(0, "grow of %s failed creating bio: "
690 		    "out of memory", p->name);
691 		return (ENOMEM);
692 	}
693 
694 	bp->bio_cmd = type;
695 	bp->bio_done = NULL;
696 	bp->bio_error = 0;
697 	bp->bio_caller1 = p;
698 	bp->bio_offset = offset;
699 	bp->bio_length = length;
700 	bp->bio_pflags |= GV_BIO_GROW;
701 	if (data == NULL)
702 		data = g_malloc(length, M_WAITOK);
703 	bp->bio_pflags |= GV_BIO_MALLOC;
704 	bp->bio_data = data;
705 
706 	gv_post_bio(sc, bp);
707 	//gv_plex_start(p, bp);
708 	return (0);
709 }
710 
711 /*
712  * Finish handling of a bio to a growing plex.
713  */
714 void
715 gv_grow_complete(struct gv_plex *p, struct bio *bp)
716 {
717 	struct gv_softc *sc;
718 	struct gv_sd *s;
719 	struct gv_volume *v;
720 	off_t origsize, offset;
721 	int sdcount, err;
722 
723 	v = p->vol_sc;
724 	KASSERT(v != NULL, ("gv_grow_complete: NULL v"));
725 	sc = v->vinumconf;
726 	KASSERT(sc != NULL, ("gv_grow_complete: NULL sc"));
727 	err = 0;
728 
729 	/* If it was a read, write it. */
730 	if (bp->bio_cmd == BIO_READ) {
731 		p->synced += bp->bio_length;
732 		err = gv_grow_request(p, bp->bio_offset, bp->bio_length,
733 		    BIO_WRITE, bp->bio_data);
734 	/* If it was a write, read next. */
735 	} else if (bp->bio_cmd == BIO_WRITE) {
736 		if (bp->bio_pflags & GV_BIO_MALLOC)
737 			g_free(bp->bio_data);
738 
739 		/* Find the real size of the plex. */
740 		sdcount = gv_sdcount(p, 1);
741 		s = LIST_FIRST(&p->subdisks);
742 		KASSERT(s != NULL, ("NULL s"));
743 		origsize = (s->size * (sdcount - 1));
744 		if (bp->bio_offset + bp->bio_length >= origsize) {
745 			G_VINUM_DEBUG(1, "growing of %s completed", p->name);
746 			p->flags &= ~GV_PLEX_GROWING;
747 			LIST_FOREACH(s, &p->subdisks, in_plex) {
748 				s->flags &= ~GV_SD_GROW;
749 				gv_set_sd_state(s, GV_SD_UP, 0);
750 			}
751 			p->size = gv_plex_size(p);
752 			gv_update_vol_size(v, gv_vol_size(v));
753 			gv_set_plex_state(p, GV_PLEX_UP, 0);
754 			g_topology_lock();
755 			gv_access(v->provider, -1, -1, 0);
756 			g_topology_unlock();
757 			p->synced = 0;
758 			gv_post_event(sc, GV_EVENT_SAVE_CONFIG, sc, NULL, 0, 0);
759 			/* Issue delayed requests. */
760 			gv_plex_flush(p);
761 		} else {
762 			offset = bp->bio_offset + bp->bio_length;
763 			err = gv_grow_request(p, offset,
764 			   MIN(bp->bio_length, origsize - offset),
765 			   BIO_READ, NULL);
766 		}
767 	}
768 	g_destroy_bio(bp);
769 
770 	if (err) {
771 		p->flags &= ~GV_PLEX_GROWING;
772 		G_VINUM_DEBUG(0, "error growing plex: error code %d", err);
773 	}
774 }
775 
776 /*
777  * Create an initialization BIO and send it off to the consumer. Assume that
778  * we're given initialization data as parameter.
779  */
780 void
781 gv_init_request(struct gv_sd *s, off_t start, caddr_t data, off_t length)
782 {
783 	struct gv_drive *d;
784 	struct g_consumer *cp;
785 	struct bio *bp, *cbp;
786 
787 	KASSERT(s != NULL, ("gv_init_request: NULL s"));
788 	d = s->drive_sc;
789 	KASSERT(d != NULL, ("gv_init_request: NULL d"));
790 	cp = d->consumer;
791 	KASSERT(cp != NULL, ("gv_init_request: NULL cp"));
792 
793 	bp = g_new_bio();
794 	if (bp == NULL) {
795 		G_VINUM_DEBUG(0, "subdisk '%s' init: write failed at offset %jd"
796 		    " (drive offset %jd); out of memory", s->name,
797 		    (intmax_t)s->initialized, (intmax_t)start);
798 		return; /* XXX: Error codes. */
799 	}
800 	bp->bio_cmd = BIO_WRITE;
801 	bp->bio_data = data;
802 	bp->bio_done = NULL;
803 	bp->bio_error = 0;
804 	bp->bio_length = length;
805 	bp->bio_pflags |= GV_BIO_INIT;
806 	bp->bio_offset = start;
807 	bp->bio_caller1 = s;
808 
809 	/* Then ofcourse, we have to clone it. */
810 	cbp = g_clone_bio(bp);
811 	if (cbp == NULL) {
812 		G_VINUM_DEBUG(0, "subdisk '%s' init: write failed at offset %jd"
813 		    " (drive offset %jd); out of memory", s->name,
814 		    (intmax_t)s->initialized, (intmax_t)start);
815 		return; /* XXX: Error codes. */
816 	}
817 	cbp->bio_done = gv_done;
818 	cbp->bio_caller1 = s;
819 	d->active++;
820 	/* Send it off to the consumer. */
821 	g_io_request(cbp, cp);
822 }
823 
824 /*
825  * Handle a finished initialization BIO.
826  */
827 void
828 gv_init_complete(struct gv_plex *p, struct bio *bp)
829 {
830 	struct gv_softc *sc;
831 	struct gv_drive *d;
832 	struct g_consumer *cp;
833 	struct gv_sd *s;
834 	off_t start, length;
835 	caddr_t data;
836 	int error;
837 
838 	s = bp->bio_caller1;
839 	start = bp->bio_offset;
840 	length = bp->bio_length;
841 	error = bp->bio_error;
842 	data = bp->bio_data;
843 
844 	KASSERT(s != NULL, ("gv_init_complete: NULL s"));
845 	d = s->drive_sc;
846 	KASSERT(d != NULL, ("gv_init_complete: NULL d"));
847 	cp = d->consumer;
848 	KASSERT(cp != NULL, ("gv_init_complete: NULL cp"));
849 	sc = p->vinumconf;
850 	KASSERT(sc != NULL, ("gv_init_complete: NULL sc"));
851 
852 	g_destroy_bio(bp);
853 
854 	/*
855 	 * First we need to find out if it was okay, and abort if it's not.
856 	 * Then we need to free previous buffers, find out the correct subdisk,
857 	 * as well as getting the correct starting point and length of the BIO.
858 	 */
859 	if (start >= s->drive_offset + s->size) {
860 		/* Free the data we initialized. */
861 		g_free(data);
862 		g_topology_assert_not();
863 		g_topology_lock();
864 		g_access(cp, 0, -1, 0);
865 		g_topology_unlock();
866 		if (error) {
867 			gv_set_sd_state(s, GV_SD_STALE, GV_SETSTATE_FORCE |
868 			    GV_SETSTATE_CONFIG);
869 		} else {
870 			gv_set_sd_state(s, GV_SD_UP, GV_SETSTATE_CONFIG);
871 			s->initialized = 0;
872 			gv_post_event(sc, GV_EVENT_SAVE_CONFIG, sc, NULL, 0, 0);
873 			G_VINUM_DEBUG(1, "subdisk '%s' init: finished "
874 			    "successfully", s->name);
875 		}
876 		return;
877 	}
878 	s->initialized += length;
879 	start += length;
880 	gv_init_request(s, start, data, length);
881 }
882 
883 /*
884  * Create a new bio struct for the next parity rebuild. Used both by internal
885  * rebuild of degraded plexes as well as user initiated rebuilds/checks.
886  */
887 void
888 gv_parity_request(struct gv_plex *p, int flags, off_t offset)
889 {
890 	struct gv_softc *sc;
891 	struct bio *bp;
892 
893 	KASSERT(p != NULL, ("gv_parity_request: NULL p"));
894 	sc = p->vinumconf;
895 	KASSERT(sc != NULL, ("gv_parity_request: NULL sc"));
896 
897 	bp = g_new_bio();
898 	if (bp == NULL) {
899 		G_VINUM_DEBUG(0, "rebuild of %s failed creating bio: "
900 		    "out of memory", p->name);
901 		return;
902 	}
903 
904 	bp->bio_cmd = BIO_WRITE;
905 	bp->bio_done = NULL;
906 	bp->bio_error = 0;
907 	bp->bio_length = p->stripesize;
908 	bp->bio_caller1 = p;
909 
910 	/*
911 	 * Check if it's a rebuild of a degraded plex or a user request of
912 	 * parity rebuild.
913 	 */
914 	if (flags & GV_BIO_REBUILD)
915 		bp->bio_data = g_malloc(GV_DFLT_SYNCSIZE, M_WAITOK);
916 	else if (flags & GV_BIO_CHECK)
917 		bp->bio_data = g_malloc(p->stripesize, M_WAITOK | M_ZERO);
918 	else {
919 		G_VINUM_DEBUG(0, "invalid flags given in rebuild");
920 		return;
921 	}
922 
923 	bp->bio_pflags = flags;
924 	bp->bio_pflags |= GV_BIO_MALLOC;
925 
926 	/* We still have more parity to build. */
927 	bp->bio_offset = offset;
928 	gv_post_bio(sc, bp);
929 	//gv_plex_start(p, bp); /* Send it down to the plex. */
930 }
931 
932 /*
933  * Handle a finished parity write.
934  */
935 void
936 gv_parity_complete(struct gv_plex *p, struct bio *bp)
937 {
938 	struct gv_softc *sc;
939 	int error, flags;
940 
941 	error = bp->bio_error;
942 	flags = bp->bio_pflags;
943 	flags &= ~GV_BIO_MALLOC;
944 
945 	sc = p->vinumconf;
946 	KASSERT(sc != NULL, ("gv_parity_complete: NULL sc"));
947 
948 	/* Clean up what we allocated. */
949 	if (bp->bio_pflags & GV_BIO_MALLOC)
950 		g_free(bp->bio_data);
951 	g_destroy_bio(bp);
952 
953 	if (error == EAGAIN) {
954 		G_VINUM_DEBUG(0, "parity incorrect at offset 0x%jx",
955 		    (intmax_t)p->synced);
956 	}
957 
958 	/* Any error is fatal, except EAGAIN when we're rebuilding. */
959 	if (error && !(error == EAGAIN && (flags & GV_BIO_PARITY))) {
960 		/* Make sure we don't have the lock. */
961 		g_topology_assert_not();
962 		g_topology_lock();
963 		gv_access(p->vol_sc->provider, -1, -1, 0);
964 		g_topology_unlock();
965 		G_VINUM_DEBUG(0, "parity check on %s failed at 0x%jx "
966 		    "errno %d", p->name, (intmax_t)p->synced, error);
967 		return;
968 	} else {
969 		p->synced += p->stripesize;
970 	}
971 
972 	if (p->synced >= p->size) {
973 		/* Make sure we don't have the lock. */
974 		g_topology_assert_not();
975 		g_topology_lock();
976 		gv_access(p->vol_sc->provider, -1, -1, 0);
977 		g_topology_unlock();
978 		/* We're finished. */
979 		G_VINUM_DEBUG(1, "parity operation on %s finished", p->name);
980 		p->synced = 0;
981 		gv_post_event(sc, GV_EVENT_SAVE_CONFIG, sc, NULL, 0, 0);
982 		return;
983 	}
984 
985 	/* Send down next. It will determine if we need to itself. */
986 	gv_parity_request(p, flags, p->synced);
987 }
988 
989 /*
990  * Handle a finished plex rebuild bio.
991  */
992 void
993 gv_rebuild_complete(struct gv_plex *p, struct bio *bp)
994 {
995 	struct gv_softc *sc;
996 	struct gv_sd *s;
997 	int error, flags;
998 	off_t offset;
999 
1000 	error = bp->bio_error;
1001 	flags = bp->bio_pflags;
1002 	offset = bp->bio_offset;
1003 	flags &= ~GV_BIO_MALLOC;
1004 	sc = p->vinumconf;
1005 	KASSERT(sc != NULL, ("gv_rebuild_complete: NULL sc"));
1006 
1007 	/* Clean up what we allocated. */
1008 	if (bp->bio_pflags & GV_BIO_MALLOC)
1009 		g_free(bp->bio_data);
1010 	g_destroy_bio(bp);
1011 
1012 	if (error) {
1013 		g_topology_assert_not();
1014 		g_topology_lock();
1015 		gv_access(p->vol_sc->provider, -1, -1, 0);
1016 		g_topology_unlock();
1017 
1018 		G_VINUM_DEBUG(0, "rebuild of %s failed at offset %jd errno: %d",
1019 		    p->name, (intmax_t)offset, error);
1020 		p->flags &= ~GV_PLEX_REBUILDING;
1021 		p->synced = 0;
1022 		gv_plex_flush(p); /* Flush out remaining rebuild BIOs. */
1023 		return;
1024 	}
1025 
1026 	offset += (p->stripesize * (gv_sdcount(p, 1) - 1));
1027 	if (offset >= p->size) {
1028 		/* We're finished. */
1029 		g_topology_assert_not();
1030 		g_topology_lock();
1031 		gv_access(p->vol_sc->provider, -1, -1, 0);
1032 		g_topology_unlock();
1033 
1034 		G_VINUM_DEBUG(1, "rebuild of %s finished", p->name);
1035 		gv_save_config(p->vinumconf);
1036 		p->flags &= ~GV_PLEX_REBUILDING;
1037 		p->synced = 0;
1038 		/* Try to up all subdisks. */
1039 		LIST_FOREACH(s, &p->subdisks, in_plex)
1040 			gv_update_sd_state(s);
1041 		gv_post_event(sc, GV_EVENT_SAVE_CONFIG, sc, NULL, 0, 0);
1042 		gv_plex_flush(p); /* Flush out remaining rebuild BIOs. */
1043 		return;
1044 	}
1045 
1046 	/* Send down next. It will determine if we need to itself. */
1047 	gv_parity_request(p, flags, offset);
1048 }
1049