xref: /freebsd/sys/geom/vinum/geom_vinum_volume.c (revision 3f0efe05432b1633991114ca4ca330102a561959)
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 
39 void
40 gv_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 
56 void
57 gv_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 
138 void
139 gv_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