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) 2013 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 for (spa_feature_t i = 0; i < SPA_FEATURES; i++) {
96 zfeature_info_t *feature = &spa_feature_table[i];
97 if (strcmp(guid, feature->fi_guid) == 0)
98 return (B_TRUE);
99 }
100 return (B_FALSE);
101 }
102
103 int
104 zfeature_lookup_name(const char *name, spa_feature_t *res)
105 {
106 for (spa_feature_t i = 0; i < SPA_FEATURES; i++) {
107 zfeature_info_t *feature = &spa_feature_table[i];
108 if (strcmp(name, feature->fi_uname) == 0) {
109 if (res != NULL)
110 *res = i;
111 return (0);
112 }
113 }
114
115 return (ENOENT);
116 }
117
118 static void
119 zfeature_register(spa_feature_t fid, const char *guid, const char *name,
120 const char *desc, boolean_t readonly, boolean_t mos,
121 const spa_feature_t *deps)
122 {
123 zfeature_info_t *feature = &spa_feature_table[fid];
124 static spa_feature_t nodeps[] = { SPA_FEATURE_NONE };
125
126 ASSERT(name != NULL);
127 ASSERT(desc != NULL);
128 ASSERT(!readonly || !mos);
129 ASSERT3U(fid, <, SPA_FEATURES);
130 ASSERT(zfeature_is_valid_guid(guid));
131
132 if (deps == NULL)
133 deps = nodeps;
134
135 feature->fi_feature = fid;
136 feature->fi_guid = guid;
137 feature->fi_uname = name;
138 feature->fi_desc = desc;
139 feature->fi_can_readonly = readonly;
140 feature->fi_mos = mos;
141 feature->fi_depends = deps;
142 }
143
144 void
145 zpool_feature_init(void)
146 {
147 zfeature_register(SPA_FEATURE_ASYNC_DESTROY,
148 "com.delphix:async_destroy", "async_destroy",
149 "Destroy filesystems asynchronously.", B_TRUE, B_FALSE, NULL);
150 zfeature_register(SPA_FEATURE_EMPTY_BPOBJ,
151 "com.delphix:empty_bpobj", "empty_bpobj",
152 "Snapshots use less space.", B_TRUE, B_FALSE, NULL);
153 zfeature_register(SPA_FEATURE_LZ4_COMPRESS,
154 "org.illumos:lz4_compress", "lz4_compress",
155 "LZ4 compression algorithm support.", B_FALSE, B_FALSE, NULL);
156 zfeature_register(SPA_FEATURE_MULTI_VDEV_CRASH_DUMP,
157 "com.joyent:multi_vdev_crash_dump", "multi_vdev_crash_dump",
158 "Crash dumps to multiple vdev pools.", B_FALSE, B_FALSE, NULL);
159 zfeature_register(SPA_FEATURE_SPACEMAP_HISTOGRAM,
160 "com.delphix:spacemap_histogram", "spacemap_histogram",
161 "Spacemaps maintain space histograms.", B_TRUE, B_FALSE, NULL);
162 zfeature_register(SPA_FEATURE_EXTENSIBLE_DATASET,
163 "com.delphix:extensible_dataset", "extensible_dataset",
164 "Enhanced dataset functionality, used by other features.",
165 B_FALSE, B_FALSE, NULL);
166 }