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 * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
25 * Copyright (c) 2013, Joyent, Inc. All rights reserved.
26 */
27
28 #ifdef _KERNEL
29 #include <sys/systm.h>
30 #else
31 #include <errno.h>
32 #include <string.h>
33 #endif
34 #include <sys/debug.h>
35 #include <sys/fs/zfs.h>
36 #include <sys/inttypes.h>
37 #include <sys/types.h>
38 #include "zfeature_common.h"
39
40 /*
41 * Set to disable all feature checks while opening pools, allowing pools with
42 * unsupported features to be opened. Set for testing only.
43 */
44 boolean_t zfeature_checks_disable = B_FALSE;
45
46 zfeature_info_t spa_feature_table[SPA_FEATURES];
47
48 /*
49 * Valid characters for feature guids. This list is mainly for aesthetic
50 * purposes and could be expanded in the future. There are different allowed
51 * characters in the guids reverse dns portion (before the colon) and its
52 * short name (after the colon).
53 */
54 static int
55 valid_char(char c, boolean_t after_colon)
56 {
57 return ((c >= 'a' && c <= 'z') ||
58 (c >= '0' && c <= '9') ||
59 c == (after_colon ? '_' : '.'));
60 }
61
62 /*
63 * Every feature guid must contain exactly one colon which separates a reverse
64 * dns organization name from the feature's "short" name (e.g.
65 * "com.company:feature_name").
66 */
67 boolean_t
68 zfeature_is_valid_guid(const char *name)
69 {
70 int i;
71 boolean_t has_colon = B_FALSE;
72
73 i = 0;
74 while (name[i] != '\0') {
75 char c = name[i++];
76 if (c == ':') {
77 if (has_colon)
78 return (B_FALSE);
79 has_colon = B_TRUE;
80 continue;
81 }
82 if (!valid_char(c, has_colon))
83 return (B_FALSE);
84 }
85
86 return (has_colon);
87 }
88
89 boolean_t
90 zfeature_is_supported(const char *guid)
91 {
92 if (zfeature_checks_disable)
93 return (B_TRUE);
94
95 return (0 == zfeature_lookup_guid(guid, NULL));
96 }
97
98 int
99 zfeature_lookup_guid(const char *guid, zfeature_info_t **res)
100 {
101 for (int i = 0; i < SPA_FEATURES; i++) {
102 zfeature_info_t *feature = &spa_feature_table[i];
103 if (strcmp(guid, feature->fi_guid) == 0) {
104 if (res != NULL)
105 *res = feature;
106 return (0);
107 }
108 }
109
110 return (ENOENT);
111 }
112
113 int
114 zfeature_lookup_name(const char *name, zfeature_info_t **res)
115 {
116 for (int i = 0; i < SPA_FEATURES; i++) {
117 zfeature_info_t *feature = &spa_feature_table[i];
118 if (strcmp(name, feature->fi_uname) == 0) {
119 if (res != NULL)
120 *res = feature;
121 return (0);
122 }
123 }
124
125 return (ENOENT);
126 }
127
128 static void
129 zfeature_register(int fid, const char *guid, const char *name, const char *desc,
130 boolean_t readonly, boolean_t mos, zfeature_info_t **deps)
131 {
132 zfeature_info_t *feature = &spa_feature_table[fid];
133 static zfeature_info_t *nodeps[] = { NULL };
134
135 ASSERT(name != NULL);
136 ASSERT(desc != NULL);
137 ASSERT(!readonly || !mos);
138 ASSERT3U(fid, <, SPA_FEATURES);
139 ASSERT(zfeature_is_valid_guid(guid));
140
141 if (deps == NULL)
142 deps = nodeps;
143
144 feature->fi_guid = guid;
145 feature->fi_uname = name;
146 feature->fi_desc = desc;
147 feature->fi_can_readonly = readonly;
148 feature->fi_mos = mos;
149 feature->fi_depends = deps;
150 }
151
152 void
153 zpool_feature_init(void)
154 {
155 zfeature_register(SPA_FEATURE_ASYNC_DESTROY,
156 "com.delphix:async_destroy", "async_destroy",
157 "Destroy filesystems asynchronously.", B_TRUE, B_FALSE, NULL);
158 zfeature_register(SPA_FEATURE_EMPTY_BPOBJ,
159 "com.delphix:empty_bpobj", "empty_bpobj",
160 "Snapshots use less space.", B_TRUE, B_FALSE, NULL);
161 zfeature_register(SPA_FEATURE_LZ4_COMPRESS,
162 "org.illumos:lz4_compress", "lz4_compress",
163 "LZ4 compression algorithm support.", B_FALSE, B_FALSE, NULL);
164 zfeature_register(SPA_FEATURE_MULTI_VDEV_CRASH_DUMP,
165 "com.joyent:multi_vdev_crash_dump", "multi_vdev_crash_dump",
166 "Crash dumps to multiple vdev pools.", B_FALSE, B_FALSE, NULL);
167 }