xref: /illumos-gate/usr/src/common/zfs/zfeature_common.c (revision 300fdee27f8b59b381c1a0316bdee52fdfdb9213)
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) 2011, 2017 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  * Copyright (c) 2014, Nexenta Systems, Inc. All rights reserved.
27  * Copyright (c) 2014 Integros [integros.com]
28  */
29 
30 #ifdef _KERNEL
31 #include <sys/systm.h>
32 #else
33 #include <errno.h>
34 #include <string.h>
35 #endif
36 #include <sys/debug.h>
37 #include <sys/fs/zfs.h>
38 #include <sys/inttypes.h>
39 #include <sys/types.h>
40 #include "zfeature_common.h"
41 
42 /*
43  * Set to disable all feature checks while opening pools, allowing pools with
44  * unsupported features to be opened. Set for testing only.
45  */
46 boolean_t zfeature_checks_disable = B_FALSE;
47 
48 zfeature_info_t spa_feature_table[SPA_FEATURES];
49 
50 /*
51  * Valid characters for feature guids. This list is mainly for aesthetic
52  * purposes and could be expanded in the future. There are different allowed
53  * characters in the guids reverse dns portion (before the colon) and its
54  * short name (after the colon).
55  */
56 static int
57 valid_char(char c, boolean_t after_colon)
58 {
59 	return ((c >= 'a' && c <= 'z') ||
60 	    (c >= '0' && c <= '9') ||
61 	    (after_colon && c == '_') ||
62 	    (!after_colon && (c == '.' || c == '-')));
63 }
64 
65 /*
66  * Every feature guid must contain exactly one colon which separates a reverse
67  * dns organization name from the feature's "short" name (e.g.
68  * "com.company:feature_name").
69  */
70 boolean_t
71 zfeature_is_valid_guid(const char *name)
72 {
73 	int i;
74 	boolean_t has_colon = B_FALSE;
75 
76 	i = 0;
77 	while (name[i] != '\0') {
78 		char c = name[i++];
79 		if (c == ':') {
80 			if (has_colon)
81 				return (B_FALSE);
82 			has_colon = B_TRUE;
83 			continue;
84 		}
85 		if (!valid_char(c, has_colon))
86 			return (B_FALSE);
87 	}
88 
89 	return (has_colon);
90 }
91 
92 boolean_t
93 zfeature_is_supported(const char *guid)
94 {
95 	if (zfeature_checks_disable)
96 		return (B_TRUE);
97 
98 	for (spa_feature_t i = 0; i < SPA_FEATURES; i++) {
99 		zfeature_info_t *feature = &spa_feature_table[i];
100 		if (strcmp(guid, feature->fi_guid) == 0)
101 			return (B_TRUE);
102 	}
103 	return (B_FALSE);
104 }
105 
106 int
107 zfeature_lookup_name(const char *name, spa_feature_t *res)
108 {
109 	for (spa_feature_t i = 0; i < SPA_FEATURES; i++) {
110 		zfeature_info_t *feature = &spa_feature_table[i];
111 		if (strcmp(name, feature->fi_uname) == 0) {
112 			if (res != NULL)
113 				*res = i;
114 			return (0);
115 		}
116 	}
117 
118 	return (ENOENT);
119 }
120 
121 boolean_t
122 zfeature_depends_on(spa_feature_t fid, spa_feature_t check)
123 {
124 	zfeature_info_t *feature = &spa_feature_table[fid];
125 
126 	for (int i = 0; feature->fi_depends[i] != SPA_FEATURE_NONE; i++) {
127 		if (feature->fi_depends[i] == check)
128 			return (B_TRUE);
129 	}
130 	return (B_FALSE);
131 }
132 
133 static boolean_t
134 deps_contains_feature(const spa_feature_t *deps, const spa_feature_t feature)
135 {
136 	for (int i = 0; deps[i] != SPA_FEATURE_NONE; i++)
137 		if (deps[i] == feature)
138 			return (B_TRUE);
139 
140 	return (B_FALSE);
141 }
142 
143 static void
144 zfeature_register(spa_feature_t fid, const char *guid, const char *name,
145     const char *desc, zfeature_flags_t flags, const spa_feature_t *deps)
146 {
147 	zfeature_info_t *feature = &spa_feature_table[fid];
148 	static spa_feature_t nodeps[] = { SPA_FEATURE_NONE };
149 
150 	ASSERT(name != NULL);
151 	ASSERT(desc != NULL);
152 	ASSERT((flags & ZFEATURE_FLAG_READONLY_COMPAT) == 0 ||
153 	    (flags & ZFEATURE_FLAG_MOS) == 0);
154 	ASSERT3U(fid, <, SPA_FEATURES);
155 	ASSERT(zfeature_is_valid_guid(guid));
156 
157 	if (deps == NULL)
158 		deps = nodeps;
159 
160 	VERIFY(((flags & ZFEATURE_FLAG_PER_DATASET) == 0) ||
161 	    (deps_contains_feature(deps, SPA_FEATURE_EXTENSIBLE_DATASET)));
162 
163 	feature->fi_feature = fid;
164 	feature->fi_guid = guid;
165 	feature->fi_uname = name;
166 	feature->fi_desc = desc;
167 	feature->fi_flags = flags;
168 	feature->fi_depends = deps;
169 }
170 
171 void
172 zpool_feature_init(void)
173 {
174 	zfeature_register(SPA_FEATURE_ASYNC_DESTROY,
175 	    "com.delphix:async_destroy", "async_destroy",
176 	    "Destroy filesystems asynchronously.",
177 	    ZFEATURE_FLAG_READONLY_COMPAT, NULL);
178 
179 	zfeature_register(SPA_FEATURE_EMPTY_BPOBJ,
180 	    "com.delphix:empty_bpobj", "empty_bpobj",
181 	    "Snapshots use less space.",
182 	    ZFEATURE_FLAG_READONLY_COMPAT, NULL);
183 
184 	zfeature_register(SPA_FEATURE_LZ4_COMPRESS,
185 	    "org.illumos:lz4_compress", "lz4_compress",
186 	    "LZ4 compression algorithm support.",
187 	    ZFEATURE_FLAG_ACTIVATE_ON_ENABLE, NULL);
188 
189 	zfeature_register(SPA_FEATURE_MULTI_VDEV_CRASH_DUMP,
190 	    "com.joyent:multi_vdev_crash_dump", "multi_vdev_crash_dump",
191 	    "Crash dumps to multiple vdev pools.",
192 	    0, NULL);
193 
194 	zfeature_register(SPA_FEATURE_SPACEMAP_HISTOGRAM,
195 	    "com.delphix:spacemap_histogram", "spacemap_histogram",
196 	    "Spacemaps maintain space histograms.",
197 	    ZFEATURE_FLAG_READONLY_COMPAT, NULL);
198 
199 	zfeature_register(SPA_FEATURE_ENABLED_TXG,
200 	    "com.delphix:enabled_txg", "enabled_txg",
201 	    "Record txg at which a feature is enabled",
202 	    ZFEATURE_FLAG_READONLY_COMPAT, NULL);
203 
204 	static spa_feature_t hole_birth_deps[] = {
205 		SPA_FEATURE_ENABLED_TXG,
206 		SPA_FEATURE_NONE
207 	};
208 	zfeature_register(SPA_FEATURE_HOLE_BIRTH,
209 	    "com.delphix:hole_birth", "hole_birth",
210 	    "Retain hole birth txg for more precise zfs send",
211 	    ZFEATURE_FLAG_MOS | ZFEATURE_FLAG_ACTIVATE_ON_ENABLE,
212 	    hole_birth_deps);
213 
214 	zfeature_register(SPA_FEATURE_EXTENSIBLE_DATASET,
215 	    "com.delphix:extensible_dataset", "extensible_dataset",
216 	    "Enhanced dataset functionality, used by other features.",
217 	    0, NULL);
218 
219 	static const spa_feature_t bookmarks_deps[] = {
220 		SPA_FEATURE_EXTENSIBLE_DATASET,
221 		SPA_FEATURE_NONE
222 	};
223 	zfeature_register(SPA_FEATURE_BOOKMARKS,
224 	    "com.delphix:bookmarks", "bookmarks",
225 	    "\"zfs bookmark\" command",
226 	    ZFEATURE_FLAG_READONLY_COMPAT, bookmarks_deps);
227 
228 	static const spa_feature_t filesystem_limits_deps[] = {
229 		SPA_FEATURE_EXTENSIBLE_DATASET,
230 		SPA_FEATURE_NONE
231 	};
232 	zfeature_register(SPA_FEATURE_FS_SS_LIMIT,
233 	    "com.joyent:filesystem_limits", "filesystem_limits",
234 	    "Filesystem and snapshot limits.",
235 	    ZFEATURE_FLAG_READONLY_COMPAT, filesystem_limits_deps);
236 
237 	zfeature_register(SPA_FEATURE_EMBEDDED_DATA,
238 	    "com.delphix:embedded_data", "embedded_data",
239 	    "Blocks which compress very well use even less space.",
240 	    ZFEATURE_FLAG_MOS | ZFEATURE_FLAG_ACTIVATE_ON_ENABLE,
241 	    NULL);
242 
243 	zfeature_register(SPA_FEATURE_POOL_CHECKPOINT,
244 	    "com.delphix:zpool_checkpoint", "zpool_checkpoint",
245 	    "Pool state can be checkpointed, allowing rewind later.",
246 	    ZFEATURE_FLAG_READONLY_COMPAT, NULL);
247 
248 	zfeature_register(SPA_FEATURE_SPACEMAP_V2,
249 	    "com.delphix:spacemap_v2", "spacemap_v2",
250 	    "Space maps representing large segments are more efficient.",
251 	    ZFEATURE_FLAG_READONLY_COMPAT | ZFEATURE_FLAG_ACTIVATE_ON_ENABLE,
252 	    NULL);
253 
254 	static const spa_feature_t large_blocks_deps[] = {
255 		SPA_FEATURE_EXTENSIBLE_DATASET,
256 		SPA_FEATURE_NONE
257 	};
258 	zfeature_register(SPA_FEATURE_LARGE_BLOCKS,
259 	    "org.open-zfs:large_blocks", "large_blocks",
260 	    "Support for blocks larger than 128KB.",
261 	    ZFEATURE_FLAG_PER_DATASET, large_blocks_deps);
262 
263 	static const spa_feature_t sha512_deps[] = {
264 		SPA_FEATURE_EXTENSIBLE_DATASET,
265 		SPA_FEATURE_NONE
266 	};
267 	zfeature_register(SPA_FEATURE_SHA512,
268 	    "org.illumos:sha512", "sha512",
269 	    "SHA-512/256 hash algorithm.",
270 	    ZFEATURE_FLAG_PER_DATASET, sha512_deps);
271 
272 	static const spa_feature_t skein_deps[] = {
273 		SPA_FEATURE_EXTENSIBLE_DATASET,
274 		SPA_FEATURE_NONE
275 	};
276 	zfeature_register(SPA_FEATURE_SKEIN,
277 	    "org.illumos:skein", "skein",
278 	    "Skein hash algorithm.",
279 	    ZFEATURE_FLAG_PER_DATASET, skein_deps);
280 
281 	static const spa_feature_t edonr_deps[] = {
282 		SPA_FEATURE_EXTENSIBLE_DATASET,
283 		SPA_FEATURE_NONE
284 	};
285 	zfeature_register(SPA_FEATURE_EDONR,
286 	    "org.illumos:edonr", "edonr",
287 	    "Edon-R hash algorithm.",
288 	    ZFEATURE_FLAG_PER_DATASET, edonr_deps);
289 
290 	zfeature_register(SPA_FEATURE_DEVICE_REMOVAL,
291 	    "com.delphix:device_removal", "device_removal",
292 	    "Top-level vdevs can be removed, reducing logical pool size.",
293 	    ZFEATURE_FLAG_MOS, NULL);
294 
295 	static const spa_feature_t obsolete_counts_deps[] = {
296 		SPA_FEATURE_EXTENSIBLE_DATASET,
297 		SPA_FEATURE_DEVICE_REMOVAL,
298 		SPA_FEATURE_NONE
299 	};
300 	zfeature_register(SPA_FEATURE_OBSOLETE_COUNTS,
301 	    "com.delphix:obsolete_counts", "obsolete_counts",
302 	    "Reduce memory used by removed devices when their blocks are "
303 	    "freed or remapped.",
304 	    ZFEATURE_FLAG_READONLY_COMPAT, obsolete_counts_deps);
305 }
306