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