1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright 2010 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 /*
27 * Copyright (c) 2013 by Delphix. All rights reserved.
28 */
29
30 #include <sys/zfs_context.h>
31 #include <sys/spa.h>
32 #include <sys/vdev_impl.h>
33 #include <sys/zio.h>
34 #include <sys/fs/zfs.h>
35
36 /*
37 * Virtual device vector for the pool's root vdev.
38 */
39
40 /*
41 * We should be able to tolerate one failure with absolutely no damage
42 * to our metadata. Two failures will take out space maps, a bunch of
43 * indirect block trees, meta dnodes, dnodes, etc. Probably not a happy
44 * place to live. When we get smarter, we can liberalize this policy.
45 * e.g. If we haven't lost two consecutive top-level vdevs, then we are
46 * probably fine. Adding bean counters during alloc/free can make this
47 * future guesswork more accurate.
48 */
49 static int
too_many_errors(vdev_t * vd,int numerrors)50 too_many_errors(vdev_t *vd, int numerrors)
51 {
52 ASSERT3U(numerrors, <=, vd->vdev_children);
53 return (numerrors > 0);
54 }
55
56 static int
vdev_root_open(vdev_t * vd,uint64_t * asize,uint64_t * max_asize,uint64_t * logical_ashift,uint64_t * physical_ashift)57 vdev_root_open(vdev_t *vd, uint64_t *asize, uint64_t *max_asize,
58 uint64_t *logical_ashift, uint64_t *physical_ashift)
59 {
60 int lasterror = 0;
61 int numerrors = 0;
62
63 if (vd->vdev_children == 0) {
64 vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
65 return (SET_ERROR(EINVAL));
66 }
67
68 vdev_open_children(vd);
69
70 for (int c = 0; c < vd->vdev_children; c++) {
71 vdev_t *cvd = vd->vdev_child[c];
72
73 if (cvd->vdev_open_error && !cvd->vdev_islog) {
74 lasterror = cvd->vdev_open_error;
75 numerrors++;
76 }
77 }
78
79 if (too_many_errors(vd, numerrors)) {
80 vd->vdev_stat.vs_aux = VDEV_AUX_NO_REPLICAS;
81 return (lasterror);
82 }
83
84 *asize = 0;
85 *max_asize = 0;
86 *logical_ashift = 0;
87 *physical_ashift = 0;
88
89 return (0);
90 }
91
92 static void
vdev_root_close(vdev_t * vd)93 vdev_root_close(vdev_t *vd)
94 {
95 for (int c = 0; c < vd->vdev_children; c++)
96 vdev_close(vd->vdev_child[c]);
97 }
98
99 static void
vdev_root_state_change(vdev_t * vd,int faulted,int degraded)100 vdev_root_state_change(vdev_t *vd, int faulted, int degraded)
101 {
102 if (too_many_errors(vd, faulted)) {
103 vdev_set_state(vd, B_FALSE, VDEV_STATE_CANT_OPEN,
104 VDEV_AUX_NO_REPLICAS);
105 } else if (degraded) {
106 vdev_set_state(vd, B_FALSE, VDEV_STATE_DEGRADED, VDEV_AUX_NONE);
107 } else {
108 vdev_set_state(vd, B_FALSE, VDEV_STATE_HEALTHY, VDEV_AUX_NONE);
109 }
110 }
111
112 vdev_ops_t vdev_root_ops = {
113 vdev_root_open,
114 vdev_root_close,
115 vdev_default_asize,
116 NULL, /* io_start - not applicable to the root */
117 NULL, /* io_done - not applicable to the root */
118 vdev_root_state_change,
119 NULL,
120 NULL,
121 VDEV_TYPE_ROOT, /* name of this vdev type */
122 B_FALSE /* not a leaf vdev */
123 };
124