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, 2018 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  * Copyright (c) 2017, Intel Corporation.
29  */
30 
31 #ifdef _KERNEL
32 #include <sys/systm.h>
33 #else
34 #include <errno.h>
35 #include <string.h>
36 #endif
37 #include <sys/debug.h>
38 #include <sys/fs/zfs.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
valid_char(char c,boolean_t after_colon)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
zfeature_is_valid_guid(const char * name)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
zfeature_is_supported(const char * guid)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
zfeature_lookup_name(const char * name,spa_feature_t * res)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
zfeature_depends_on(spa_feature_t fid,spa_feature_t check)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 void
zfeature_register(spa_feature_t fid,const char * guid,const char * name,const char * desc,zfeature_flags_t flags,const spa_feature_t * deps)134 zfeature_register(spa_feature_t fid, const char *guid, const char *name,
135     const char *desc, zfeature_flags_t flags, const spa_feature_t *deps)
136 {
137 	zfeature_info_t *feature = &spa_feature_table[fid];
138 	static spa_feature_t nodeps[] = { SPA_FEATURE_NONE };
139 
140 	ASSERT(name != NULL);
141 	ASSERT(desc != NULL);
142 	ASSERT((flags & ZFEATURE_FLAG_READONLY_COMPAT) == 0 ||
143 	    (flags & ZFEATURE_FLAG_MOS) == 0);
144 	ASSERT3U(fid, <, SPA_FEATURES);
145 	ASSERT(zfeature_is_valid_guid(guid));
146 
147 	if (deps == NULL)
148 		deps = nodeps;
149 
150 	feature->fi_feature = fid;
151 	feature->fi_guid = guid;
152 	feature->fi_uname = name;
153 	feature->fi_desc = desc;
154 	feature->fi_flags = flags;
155 	feature->fi_depends = deps;
156 }
157 
158 void
zpool_feature_init(void)159 zpool_feature_init(void)
160 {
161 	zfeature_register(SPA_FEATURE_ASYNC_DESTROY,
162 	    "com.delphix:async_destroy", "async_destroy",
163 	    "Destroy filesystems asynchronously.",
164 	    ZFEATURE_FLAG_READONLY_COMPAT, NULL);
165 
166 	zfeature_register(SPA_FEATURE_EMPTY_BPOBJ,
167 	    "com.delphix:empty_bpobj", "empty_bpobj",
168 	    "Snapshots use less space.",
169 	    ZFEATURE_FLAG_READONLY_COMPAT, NULL);
170 
171 	zfeature_register(SPA_FEATURE_LZ4_COMPRESS,
172 	    "org.illumos:lz4_compress", "lz4_compress",
173 	    "LZ4 compression algorithm support.",
174 	    ZFEATURE_FLAG_ACTIVATE_ON_ENABLE, NULL);
175 
176 	zfeature_register(SPA_FEATURE_MULTI_VDEV_CRASH_DUMP,
177 	    "com.joyent:multi_vdev_crash_dump", "multi_vdev_crash_dump",
178 	    "Crash dumps to multiple vdev pools.",
179 	    0, NULL);
180 
181 	zfeature_register(SPA_FEATURE_SPACEMAP_HISTOGRAM,
182 	    "com.delphix:spacemap_histogram", "spacemap_histogram",
183 	    "Spacemaps maintain space histograms.",
184 	    ZFEATURE_FLAG_READONLY_COMPAT, NULL);
185 
186 	zfeature_register(SPA_FEATURE_ENABLED_TXG,
187 	    "com.delphix:enabled_txg", "enabled_txg",
188 	    "Record txg at which a feature is enabled",
189 	    ZFEATURE_FLAG_READONLY_COMPAT, NULL);
190 
191 	static spa_feature_t hole_birth_deps[] = { SPA_FEATURE_ENABLED_TXG,
192 	    SPA_FEATURE_NONE };
193 	zfeature_register(SPA_FEATURE_HOLE_BIRTH,
194 	    "com.delphix:hole_birth", "hole_birth",
195 	    "Retain hole birth txg for more precise zfs send",
196 	    ZFEATURE_FLAG_MOS | ZFEATURE_FLAG_ACTIVATE_ON_ENABLE,
197 	    hole_birth_deps);
198 
199 	zfeature_register(SPA_FEATURE_EXTENSIBLE_DATASET,
200 	    "com.delphix:extensible_dataset", "extensible_dataset",
201 	    "Enhanced dataset functionality, used by other features.",
202 	    0, NULL);
203 
204 	static const spa_feature_t bookmarks_deps[] = {
205 		SPA_FEATURE_EXTENSIBLE_DATASET,
206 		SPA_FEATURE_NONE
207 	};
208 	zfeature_register(SPA_FEATURE_BOOKMARKS,
209 	    "com.delphix:bookmarks", "bookmarks",
210 	    "\"zfs bookmark\" command",
211 	    ZFEATURE_FLAG_READONLY_COMPAT, bookmarks_deps);
212 
213 	static const spa_feature_t filesystem_limits_deps[] = {
214 	    SPA_FEATURE_EXTENSIBLE_DATASET,
215 	    SPA_FEATURE_NONE
216 	};
217 	zfeature_register(SPA_FEATURE_FS_SS_LIMIT,
218 	    "com.joyent:filesystem_limits", "filesystem_limits",
219 	    "Filesystem and snapshot limits.",
220 	    ZFEATURE_FLAG_READONLY_COMPAT, filesystem_limits_deps);
221 
222 	zfeature_register(SPA_FEATURE_EMBEDDED_DATA,
223 	    "com.delphix:embedded_data", "embedded_data",
224 	    "Blocks which compress very well use even less space.",
225 	    ZFEATURE_FLAG_MOS | ZFEATURE_FLAG_ACTIVATE_ON_ENABLE,
226 	    NULL);
227 
228 	zfeature_register(SPA_FEATURE_POOL_CHECKPOINT,
229 	    "com.delphix:zpool_checkpoint", "zpool_checkpoint",
230 	    "Pool state can be checkpointed, allowing rewind later.",
231 	    ZFEATURE_FLAG_READONLY_COMPAT, NULL);
232 
233 	zfeature_register(SPA_FEATURE_SPACEMAP_V2,
234 	    "com.delphix:spacemap_v2", "spacemap_v2",
235 	    "Space maps representing large segments are more efficient.",
236 	    ZFEATURE_FLAG_READONLY_COMPAT | ZFEATURE_FLAG_ACTIVATE_ON_ENABLE,
237 	    NULL);
238 
239 	static const spa_feature_t large_blocks_deps[] = {
240 		SPA_FEATURE_EXTENSIBLE_DATASET,
241 		SPA_FEATURE_NONE
242 	};
243 	zfeature_register(SPA_FEATURE_LARGE_BLOCKS,
244 	    "org.open-zfs:large_blocks", "large_blocks",
245 	    "Support for blocks larger than 128KB.",
246 	    ZFEATURE_FLAG_PER_DATASET, large_blocks_deps);
247 
248 	{
249 	static const spa_feature_t large_dnode_deps[] = {
250 		SPA_FEATURE_EXTENSIBLE_DATASET,
251 		SPA_FEATURE_NONE
252 	};
253 	zfeature_register(SPA_FEATURE_LARGE_DNODE,
254 	    "org.zfsonlinux:large_dnode", "large_dnode",
255 	    "Variable on-disk size of dnodes.",
256 	    ZFEATURE_FLAG_PER_DATASET, large_dnode_deps);
257 	}
258 
259 	static const spa_feature_t sha512_deps[] = {
260 		SPA_FEATURE_EXTENSIBLE_DATASET,
261 		SPA_FEATURE_NONE
262 	};
263 	zfeature_register(SPA_FEATURE_SHA512,
264 	    "org.illumos:sha512", "sha512",
265 	    "SHA-512/256 hash algorithm.",
266 	    ZFEATURE_FLAG_PER_DATASET, sha512_deps);
267 
268 	static const spa_feature_t skein_deps[] = {
269 		SPA_FEATURE_EXTENSIBLE_DATASET,
270 		SPA_FEATURE_NONE
271 	};
272 	zfeature_register(SPA_FEATURE_SKEIN,
273 	    "org.illumos:skein", "skein",
274 	    "Skein hash algorithm.",
275 	    ZFEATURE_FLAG_PER_DATASET, skein_deps);
276 
277 #ifdef illumos
278 	static const spa_feature_t edonr_deps[] = {
279 		SPA_FEATURE_EXTENSIBLE_DATASET,
280 		SPA_FEATURE_NONE
281 	};
282 	zfeature_register(SPA_FEATURE_EDONR,
283 	    "org.illumos:edonr", "edonr",
284 	    "Edon-R hash algorithm.",
285 	    ZFEATURE_FLAG_PER_DATASET, edonr_deps);
286 #endif
287 
288 	zfeature_register(SPA_FEATURE_DEVICE_REMOVAL,
289 	    "com.delphix:device_removal", "device_removal",
290 	    "Top-level vdevs can be removed, reducing logical pool size.",
291 	    ZFEATURE_FLAG_MOS, NULL);
292 
293 	static const spa_feature_t obsolete_counts_deps[] = {
294 		SPA_FEATURE_EXTENSIBLE_DATASET,
295 		SPA_FEATURE_DEVICE_REMOVAL,
296 		SPA_FEATURE_NONE
297 	};
298 	zfeature_register(SPA_FEATURE_OBSOLETE_COUNTS,
299 	    "com.delphix:obsolete_counts", "obsolete_counts",
300 	    "Reduce memory used by removed devices when their blocks are "
301 	    "freed or remapped.",
302 	    ZFEATURE_FLAG_READONLY_COMPAT, obsolete_counts_deps);
303 
304 	{
305 	zfeature_register(SPA_FEATURE_ALLOCATION_CLASSES,
306 	    "org.zfsonlinux:allocation_classes", "allocation_classes",
307 	    "Support for separate allocation classes.",
308 	    ZFEATURE_FLAG_READONLY_COMPAT, NULL);
309 	}
310 }
311