1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2007 Lukas Ertl
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <sys/param.h>
30#include <sys/bio.h>
31#include <sys/lock.h>
32#include <sys/malloc.h>
33#include <sys/systm.h>
34
35#include <geom/geom.h>
36#include <geom/vinum/geom_vinum_var.h>
37#include <geom/vinum/geom_vinum.h>
38
39void
40gv_volume_flush(struct gv_volume *v)
41{
42	struct gv_softc *sc;
43	struct bio *bp;
44
45	KASSERT(v != NULL, ("NULL v"));
46	sc = v->vinumconf;
47	KASSERT(sc != NULL, ("NULL sc"));
48
49	bp = bioq_takefirst(v->wqueue);
50	while (bp != NULL) {
51		gv_volume_start(sc, bp);
52		bp = bioq_takefirst(v->wqueue);
53	}
54}
55
56void
57gv_volume_start(struct gv_softc *sc, struct bio *bp)
58{
59	struct gv_volume *v;
60	struct gv_plex *p, *lp;
61	int numwrites;
62
63	v = bp->bio_to->private;
64	if (v == NULL || v->state != GV_VOL_UP) {
65		g_io_deliver(bp, ENXIO);
66		return;
67	}
68
69	switch (bp->bio_cmd) {
70	case BIO_READ:
71		/*
72		 * Try to find a good plex where we can send the request to,
73		 * round-robin-style.  The plex either has to be up, or it's a
74		 * degraded RAID5 plex. Check if we have delayed requests. Put
75		 * this request on the delayed queue if so. This makes sure that
76		 * we don't read old values.
77		 */
78		if (bioq_first(v->wqueue) != NULL) {
79			bioq_insert_tail(v->wqueue, bp);
80			break;
81		}
82		lp = v->last_read_plex;
83		if (lp == NULL)
84			lp = LIST_FIRST(&v->plexes);
85		p = LIST_NEXT(lp, in_volume);
86		if (p == NULL)
87			p = LIST_FIRST(&v->plexes);
88		do {
89			if (p == NULL) {
90				p = lp;
91				break;
92			}
93			if ((p->state > GV_PLEX_DEGRADED) ||
94			    (p->state >= GV_PLEX_DEGRADED &&
95			    p->org == GV_PLEX_RAID5))
96				break;
97			p = LIST_NEXT(p, in_volume);
98			if (p == NULL)
99				p = LIST_FIRST(&v->plexes);
100		} while (p != lp);
101
102		if ((p == NULL) ||
103		    (p->org == GV_PLEX_RAID5 && p->state < GV_PLEX_DEGRADED) ||
104		    (p->org != GV_PLEX_RAID5 && p->state <= GV_PLEX_DEGRADED)) {
105			g_io_deliver(bp, ENXIO);
106			return;
107		}
108		v->last_read_plex = p;
109
110		/* Hand it down to the plex logic. */
111		gv_plex_start(p, bp);
112		break;
113
114	case BIO_WRITE:
115	case BIO_DELETE:
116		/* Delay write-requests if any plex is synchronizing. */
117		LIST_FOREACH(p, &v->plexes, in_volume) {
118			if (p->flags & GV_PLEX_SYNCING) {
119				bioq_insert_tail(v->wqueue, bp);
120				return;
121			}
122		}
123
124		numwrites = 0;
125		/* Give the BIO to each plex of this volume. */
126		LIST_FOREACH(p, &v->plexes, in_volume) {
127			if (p->state < GV_PLEX_DEGRADED)
128				continue;
129			gv_plex_start(p, bp);
130			numwrites++;
131		}
132		if (numwrites == 0)
133			g_io_deliver(bp, ENXIO);
134		break;
135	}
136}
137
138void
139gv_bio_done(struct gv_softc *sc, struct bio *bp)
140{
141	struct gv_volume *v __diagused;
142	struct gv_plex *p;
143	struct gv_sd *s;
144
145	s = bp->bio_caller1;
146	KASSERT(s != NULL, ("gv_bio_done: NULL s"));
147	p = s->plex_sc;
148	KASSERT(p != NULL, ("gv_bio_done: NULL p"));
149	v = p->vol_sc;
150	KASSERT(v != NULL, ("gv_bio_done: NULL v"));
151
152	switch (p->org) {
153	case GV_PLEX_CONCAT:
154	case GV_PLEX_STRIPED:
155		gv_plex_normal_done(p, bp);
156		break;
157	case GV_PLEX_RAID5:
158		gv_plex_raid5_done(p, bp);
159		break;
160	}
161
162	gv_drive_done(s->drive_sc);
163}
164