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 /* 23 * Copyright (c) 2012 by Delphix. All rights reserved. 24 */ 25 26 #ifdef _KERNEL 27 #include <sys/systm.h> 28 #else 29 #include <errno.h> 30 #include <string.h> 31 #endif 32 #include <sys/debug.h> 33 #include <sys/fs/zfs.h> 34 #include <sys/inttypes.h> 35 #include <sys/types.h> 36 #include "zfeature_common.h" 37 38 /* 39 * Set to disable all feature checks while opening pools, allowing pools with 40 * unsupported features to be opened. Set for testing only. 41 */ 42 boolean_t zfeature_checks_disable = B_FALSE; 43 44 zfeature_info_t spa_feature_table[SPA_FEATURES]; 45 46 /* 47 * Valid characters for feature guids. This list is mainly for aesthetic 48 * purposes and could be expanded in the future. There are different allowed 49 * characters in the guids reverse dns portion (before the colon) and its 50 * short name (after the colon). 51 */ 52 static int 53 valid_char(char c, boolean_t after_colon) 54 { 55 return ((c >= 'a' && c <= 'z') || 56 (c >= '0' && c <= '9') || 57 c == (after_colon ? '_' : '.')); 58 } 59 60 /* 61 * Every feature guid must contain exactly one colon which separates a reverse 62 * dns organization name from the feature's "short" name (e.g. 63 * "com.company:feature_name"). 64 */ 65 boolean_t 66 zfeature_is_valid_guid(const char *name) 67 { 68 int i; 69 boolean_t has_colon = B_FALSE; 70 71 i = 0; 72 while (name[i] != '\0') { 73 char c = name[i++]; 74 if (c == ':') { 75 if (has_colon) 76 return (B_FALSE); 77 has_colon = B_TRUE; 78 continue; 79 } 80 if (!valid_char(c, has_colon)) 81 return (B_FALSE); 82 } 83 84 return (has_colon); 85 } 86 87 boolean_t 88 zfeature_is_supported(const char *guid) 89 { 90 if (zfeature_checks_disable) 91 return (B_TRUE); 92 93 return (0 == zfeature_lookup_guid(guid, NULL)); 94 } 95 96 int 97 zfeature_lookup_guid(const char *guid, zfeature_info_t **res) 98 { 99 for (int i = 0; i < SPA_FEATURES; i++) { 100 zfeature_info_t *feature = &spa_feature_table[i]; 101 if (strcmp(guid, feature->fi_guid) == 0) { 102 if (res != NULL) 103 *res = feature; 104 return (0); 105 } 106 } 107 108 return (ENOENT); 109 } 110 111 int 112 zfeature_lookup_name(const char *name, zfeature_info_t **res) 113 { 114 for (int i = 0; i < SPA_FEATURES; i++) { 115 zfeature_info_t *feature = &spa_feature_table[i]; 116 if (strcmp(name, feature->fi_uname) == 0) { 117 if (res != NULL) 118 *res = feature; 119 return (0); 120 } 121 } 122 123 return (ENOENT); 124 } 125 126 static void 127 zfeature_register(int fid, const char *guid, const char *name, const char *desc, 128 boolean_t readonly, boolean_t mos, zfeature_info_t **deps) 129 { 130 zfeature_info_t *feature = &spa_feature_table[fid]; 131 static zfeature_info_t *nodeps[] = { NULL }; 132 133 ASSERT(name != NULL); 134 ASSERT(desc != NULL); 135 ASSERT(!readonly || !mos); 136 ASSERT3U(fid, <, SPA_FEATURES); 137 ASSERT(zfeature_is_valid_guid(guid)); 138 139 if (deps == NULL) 140 deps = nodeps; 141 142 feature->fi_guid = guid; 143 feature->fi_uname = name; 144 feature->fi_desc = desc; 145 feature->fi_can_readonly = readonly; 146 feature->fi_mos = mos; 147 feature->fi_depends = deps; 148 } 149 150 void 151 zpool_feature_init(void) 152 { 153 zfeature_register(SPA_FEATURE_ASYNC_DESTROY, 154 "com.delphix:async_destroy", "async_destroy", 155 "Destroy filesystems asynchronously.", B_TRUE, B_FALSE, NULL); 156 zfeature_register(SPA_FEATURE_EMPTY_BPOBJ, 157 "com.delphix:empty_bpobj", "empty_bpobj", 158 "Snapshots use less space.", B_TRUE, B_FALSE, NULL); 159 } 160