1 /*-
2 * Copyright (c) 2007 Lukas Ertl
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 AUTHOR 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 AUTHOR 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: releng/10.0/sys/geom/vinum/geom_vinum_volume.c 190507 2009-03-28 17:20:08Z lulf $");
29
30 #include <sys/param.h>
31 #include <sys/bio.h>
32 #include <sys/lock.h>
33 #include <sys/malloc.h>
34 #include <sys/systm.h>
35
36 #include <geom/geom.h>
37 #include <geom/vinum/geom_vinum_var.h>
38 #include <geom/vinum/geom_vinum.h>
39
40 void
41 gv_volume_flush(struct gv_volume *v)
42 {
43 struct gv_softc *sc;
44 struct bio *bp;
45
46 KASSERT(v != NULL, ("NULL v"));
47 sc = v->vinumconf;
48 KASSERT(sc != NULL, ("NULL sc"));
49
50 bp = bioq_takefirst(v->wqueue);
51 while (bp != NULL) {
52 gv_volume_start(sc, bp);
53 bp = bioq_takefirst(v->wqueue);
54 }
55 }
56
57 void
58 gv_volume_start(struct gv_softc *sc, struct bio *bp)
59 {
60 struct g_geom *gp;
61 struct gv_volume *v;
62 struct gv_plex *p, *lp;
63 int numwrites;
64
65 gp = sc->geom;
66 v = bp->bio_to->private;
67 if (v == NULL || v->state != GV_VOL_UP) {
68 g_io_deliver(bp, ENXIO);
69 return;
70 }
71
72 switch (bp->bio_cmd) {
73 case BIO_READ:
74 /*
75 * Try to find a good plex where we can send the request to,
76 * round-robin-style. The plex either has to be up, or it's a
77 * degraded RAID5 plex. Check if we have delayed requests. Put
78 * this request on the delayed queue if so. This makes sure that
79 * we don't read old values.
80 */
81 if (bioq_first(v->wqueue) != NULL) {
82 bioq_insert_tail(v->wqueue, bp);
83 break;
84 }
85 lp = v->last_read_plex;
86 if (lp == NULL)
87 lp = LIST_FIRST(&v->plexes);
88 p = LIST_NEXT(lp, in_volume);
89 if (p == NULL)
90 p = LIST_FIRST(&v->plexes);
91 do {
92 if (p == NULL) {
93 p = lp;
94 break;
95 }
96 if ((p->state > GV_PLEX_DEGRADED) ||
97 (p->state >= GV_PLEX_DEGRADED &&
98 p->org == GV_PLEX_RAID5))
99 break;
100 p = LIST_NEXT(p, in_volume);
101 if (p == NULL)
102 p = LIST_FIRST(&v->plexes);
103 } while (p != lp);
104
105 if ((p == NULL) ||
106 (p->org == GV_PLEX_RAID5 && p->state < GV_PLEX_DEGRADED) ||
107 (p->org != GV_PLEX_RAID5 && p->state <= GV_PLEX_DEGRADED)) {
108 g_io_deliver(bp, ENXIO);
109 return;
110 }
111 v->last_read_plex = p;
112
113 /* Hand it down to the plex logic. */
114 gv_plex_start(p, bp);
115 break;
116
117 case BIO_WRITE:
118 case BIO_DELETE:
119 /* Delay write-requests if any plex is synchronizing. */
120 LIST_FOREACH(p, &v->plexes, in_volume) {
121 if (p->flags & GV_PLEX_SYNCING) {
122 bioq_insert_tail(v->wqueue, bp);
123 return;
124 }
125 }
126
127 numwrites = 0;
128 /* Give the BIO to each plex of this volume. */
129 LIST_FOREACH(p, &v->plexes, in_volume) {
130 if (p->state < GV_PLEX_DEGRADED)
131 continue;
132 gv_plex_start(p, bp);
133 numwrites++;
134 }
135 if (numwrites == 0)
136 g_io_deliver(bp, ENXIO);
137 break;
138 }
139 }
140
141 void
142 gv_bio_done(struct gv_softc *sc, struct bio *bp)
143 {
144 struct gv_volume *v;
145 struct gv_plex *p;
146 struct gv_sd *s;
147
148 s = bp->bio_caller1;
149 KASSERT(s != NULL, ("gv_bio_done: NULL s"));
150 p = s->plex_sc;
151 KASSERT(p != NULL, ("gv_bio_done: NULL p"));
152 v = p->vol_sc;
153 KASSERT(v != NULL, ("gv_bio_done: NULL v"));
154
155 switch (p->org) {
156 case GV_PLEX_CONCAT:
157 case GV_PLEX_STRIPED:
158 gv_plex_normal_done(p, bp);
159 break;
160 case GV_PLEX_RAID5:
161 gv_plex_raid5_done(p, bp);
162 break;
163 }
164 }
Cache object: b96a61bff96ed672f7ce8b580614cb95
|