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 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 #include <sys/zfs_context.h> 29 #include <sys/spa.h> 30 #include <sys/vdev_impl.h> 31 #include <sys/zio.h> 32 #include <sys/fs/zfs.h> 33 34 /* 35 * Virtual device vector for the pool's root vdev. 36 */ 37 38 /* 39 * We should be able to tolerate one failure with absolutely no damage 40 * to our metadata. Two failures will take out space maps, a bunch of 41 * indirect block trees, meta dnodes, dnodes, etc. Probably not a happy 42 * place to live. When we get smarter, we can liberalize this policy. 43 * e.g. If we haven't lost two consecutive top-level vdevs, then we are 44 * probably fine. Adding bean counters during alloc/free can make this 45 * future guesswork more accurate. 46 */ 47 static int 48 too_many_errors(vdev_t *vd, int numerrors) 49 { 50 ASSERT3U(numerrors, <=, vd->vdev_children); 51 return (numerrors == vd->vdev_children); 52 } 53 54 static int 55 vdev_root_open(vdev_t *vd, uint64_t *asize, uint64_t *ashift) 56 { 57 int c; 58 int lasterror = 0; 59 int numerrors = 0; 60 61 if (vd->vdev_children == 0) { 62 vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL; 63 return (EINVAL); 64 } 65 66 for (c = 0; c < vd->vdev_children; c++) { 67 vdev_t *cvd = vd->vdev_child[c]; 68 int error; 69 70 if ((error = vdev_open(cvd)) != 0) { 71 lasterror = error; 72 numerrors++; 73 continue; 74 } 75 } 76 77 if (numerrors > 0) { 78 if (!too_many_errors(vd, numerrors)) { 79 /* XXX - should not be explicitly setting this state */ 80 vdev_set_state(vd, B_FALSE, VDEV_STATE_FAULTED, 81 VDEV_AUX_NO_REPLICAS); 82 } else { 83 vd->vdev_stat.vs_aux = VDEV_AUX_NO_REPLICAS; 84 return (lasterror); 85 } 86 } 87 88 *asize = 0; 89 *ashift = 0; 90 91 return (0); 92 } 93 94 static void 95 vdev_root_close(vdev_t *vd) 96 { 97 int c; 98 99 for (c = 0; c < vd->vdev_children; c++) 100 vdev_close(vd->vdev_child[c]); 101 } 102 103 static void 104 vdev_root_state_change(vdev_t *vd, int faulted, int degraded) 105 { 106 if (faulted) { 107 if (too_many_errors(vd, faulted)) 108 vdev_set_state(vd, B_FALSE, VDEV_STATE_CANT_OPEN, 109 VDEV_AUX_NO_REPLICAS); 110 else 111 vdev_set_state(vd, B_FALSE, VDEV_STATE_FAULTED, 112 VDEV_AUX_NO_REPLICAS); 113 } else if (degraded) { 114 vdev_set_state(vd, B_FALSE, VDEV_STATE_DEGRADED, VDEV_AUX_NONE); 115 } else { 116 vdev_set_state(vd, B_FALSE, VDEV_STATE_HEALTHY, VDEV_AUX_NONE); 117 } 118 } 119 120 vdev_ops_t vdev_root_ops = { 121 vdev_root_open, 122 vdev_root_close, 123 NULL, 124 vdev_default_asize, 125 NULL, /* io_start - not applicable to the root */ 126 NULL, /* io_done - not applicable to the root */ 127 vdev_root_state_change, 128 VDEV_TYPE_ROOT, /* name of this vdev type */ 129 B_FALSE /* not a leaf vdev */ 130 }; 131