xref: /titanic_44/usr/src/common/zfs/zfeature_common.c (revision 77b65ce69d04f1ba0eceb747081964672b718796)
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, 2015 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  */
28 
29 #ifdef _KERNEL
30 #include <sys/systm.h>
31 #else
32 #include <errno.h>
33 #include <string.h>
34 #endif
35 #include <sys/debug.h>
36 #include <sys/fs/zfs.h>
37 #include <sys/inttypes.h>
38 #include <sys/types.h>
39 #include "zfeature_common.h"
40 
41 /*
42  * Set to disable all feature checks while opening pools, allowing pools with
43  * unsupported features to be opened. Set for testing only.
44  */
45 boolean_t zfeature_checks_disable = B_FALSE;
46 
47 zfeature_info_t spa_feature_table[SPA_FEATURES];
48 
49 /*
50  * Valid characters for feature guids. This list is mainly for aesthetic
51  * purposes and could be expanded in the future. There are different allowed
52  * characters in the guids reverse dns portion (before the colon) and its
53  * short name (after the colon).
54  */
55 static int
56 valid_char(char c, boolean_t after_colon)
57 {
58 	return ((c >= 'a' && c <= 'z') ||
59 	    (c >= '0' && c <= '9') ||
60 	    (after_colon && c == '_') ||
61 	    (!after_colon && (c == '.' || c == '-')));
62 }
63 
64 /*
65  * Every feature guid must contain exactly one colon which separates a reverse
66  * dns organization name from the feature's "short" name (e.g.
67  * "com.company:feature_name").
68  */
69 boolean_t
70 zfeature_is_valid_guid(const char *name)
71 {
72 	int i;
73 	boolean_t has_colon = B_FALSE;
74 
75 	i = 0;
76 	while (name[i] != '\0') {
77 		char c = name[i++];
78 		if (c == ':') {
79 			if (has_colon)
80 				return (B_FALSE);
81 			has_colon = B_TRUE;
82 			continue;
83 		}
84 		if (!valid_char(c, has_colon))
85 			return (B_FALSE);
86 	}
87 
88 	return (has_colon);
89 }
90 
91 boolean_t
92 zfeature_is_supported(const char *guid)
93 {
94 	if (zfeature_checks_disable)
95 		return (B_TRUE);
96 
97 	for (spa_feature_t i = 0; i < SPA_FEATURES; i++) {
98 		zfeature_info_t *feature = &spa_feature_table[i];
99 		if (strcmp(guid, feature->fi_guid) == 0)
100 			return (B_TRUE);
101 	}
102 	return (B_FALSE);
103 }
104 
105 int
106 zfeature_lookup_name(const char *name, spa_feature_t *res)
107 {
108 	for (spa_feature_t i = 0; i < SPA_FEATURES; i++) {
109 		zfeature_info_t *feature = &spa_feature_table[i];
110 		if (strcmp(name, feature->fi_uname) == 0) {
111 			if (res != NULL)
112 				*res = i;
113 			return (0);
114 		}
115 	}
116 
117 	return (ENOENT);
118 }
119 
120 boolean_t
121 zfeature_depends_on(spa_feature_t fid, spa_feature_t check) {
122 	zfeature_info_t *feature = &spa_feature_table[fid];
123 
124 	for (int i = 0; feature->fi_depends[i] != SPA_FEATURE_NONE; i++) {
125 		if (feature->fi_depends[i] == check)
126 			return (B_TRUE);
127 	}
128 	return (B_FALSE);
129 }
130 
131 static void
132 zfeature_register(spa_feature_t fid, const char *guid, const char *name,
133     const char *desc, zfeature_flags_t flags, const spa_feature_t *deps)
134 {
135 	zfeature_info_t *feature = &spa_feature_table[fid];
136 	static spa_feature_t nodeps[] = { SPA_FEATURE_NONE };
137 
138 	ASSERT(name != NULL);
139 	ASSERT(desc != NULL);
140 	ASSERT((flags & ZFEATURE_FLAG_READONLY_COMPAT) == 0 ||
141 	    (flags & ZFEATURE_FLAG_MOS) == 0);
142 	ASSERT3U(fid, <, SPA_FEATURES);
143 	ASSERT(zfeature_is_valid_guid(guid));
144 
145 	if (deps == NULL)
146 		deps = nodeps;
147 
148 	feature->fi_feature = fid;
149 	feature->fi_guid = guid;
150 	feature->fi_uname = name;
151 	feature->fi_desc = desc;
152 	feature->fi_flags = flags;
153 	feature->fi_depends = deps;
154 }
155 
156 void
157 zpool_feature_init(void)
158 {
159 	zfeature_register(SPA_FEATURE_ASYNC_DESTROY,
160 	    "com.delphix:async_destroy", "async_destroy",
161 	    "Destroy filesystems asynchronously.",
162 	    ZFEATURE_FLAG_READONLY_COMPAT, NULL);
163 
164 	zfeature_register(SPA_FEATURE_EMPTY_BPOBJ,
165 	    "com.delphix:empty_bpobj", "empty_bpobj",
166 	    "Snapshots use less space.",
167 	    ZFEATURE_FLAG_READONLY_COMPAT, NULL);
168 
169 	zfeature_register(SPA_FEATURE_LZ4_COMPRESS,
170 	    "org.illumos:lz4_compress", "lz4_compress",
171 	    "LZ4 compression algorithm support.",
172 	    ZFEATURE_FLAG_ACTIVATE_ON_ENABLE, NULL);
173 
174 	zfeature_register(SPA_FEATURE_MULTI_VDEV_CRASH_DUMP,
175 	    "com.joyent:multi_vdev_crash_dump", "multi_vdev_crash_dump",
176 	    "Crash dumps to multiple vdev pools.",
177 	    0, NULL);
178 
179 	zfeature_register(SPA_FEATURE_SPACEMAP_HISTOGRAM,
180 	    "com.delphix:spacemap_histogram", "spacemap_histogram",
181 	    "Spacemaps maintain space histograms.",
182 	    ZFEATURE_FLAG_READONLY_COMPAT, NULL);
183 
184 	zfeature_register(SPA_FEATURE_ENABLED_TXG,
185 	    "com.delphix:enabled_txg", "enabled_txg",
186 	    "Record txg at which a feature is enabled",
187 	    ZFEATURE_FLAG_READONLY_COMPAT, NULL);
188 
189 	static spa_feature_t hole_birth_deps[] = { SPA_FEATURE_ENABLED_TXG,
190 	    SPA_FEATURE_NONE };
191 	zfeature_register(SPA_FEATURE_HOLE_BIRTH,
192 	    "com.delphix:hole_birth", "hole_birth",
193 	    "Retain hole birth txg for more precise zfs send",
194 	    ZFEATURE_FLAG_MOS | ZFEATURE_FLAG_ACTIVATE_ON_ENABLE,
195 	    hole_birth_deps);
196 
197 	zfeature_register(SPA_FEATURE_EXTENSIBLE_DATASET,
198 	    "com.delphix:extensible_dataset", "extensible_dataset",
199 	    "Enhanced dataset functionality, used by other features.",
200 	    0, NULL);
201 
202 	static const spa_feature_t bookmarks_deps[] = {
203 		SPA_FEATURE_EXTENSIBLE_DATASET,
204 		SPA_FEATURE_NONE
205 	};
206 	zfeature_register(SPA_FEATURE_BOOKMARKS,
207 	    "com.delphix:bookmarks", "bookmarks",
208 	    "\"zfs bookmark\" command",
209 	    ZFEATURE_FLAG_READONLY_COMPAT, bookmarks_deps);
210 
211 	static const spa_feature_t filesystem_limits_deps[] = {
212 	    SPA_FEATURE_EXTENSIBLE_DATASET,
213 	    SPA_FEATURE_NONE
214 	};
215 	zfeature_register(SPA_FEATURE_FS_SS_LIMIT,
216 	    "com.joyent:filesystem_limits", "filesystem_limits",
217 	    "Filesystem and snapshot limits.",
218 	    ZFEATURE_FLAG_READONLY_COMPAT, filesystem_limits_deps);
219 
220 	zfeature_register(SPA_FEATURE_EMBEDDED_DATA,
221 	    "com.delphix:embedded_data", "embedded_data",
222 	    "Blocks which compress very well use even less space.",
223 	    ZFEATURE_FLAG_MOS | ZFEATURE_FLAG_ACTIVATE_ON_ENABLE,
224 	    NULL);
225 
226 	static const spa_feature_t large_blocks_deps[] = {
227 		SPA_FEATURE_EXTENSIBLE_DATASET,
228 		SPA_FEATURE_NONE
229 	};
230 	zfeature_register(SPA_FEATURE_LARGE_BLOCKS,
231 	    "org.open-zfs:large_blocks", "large_blocks",
232 	    "Support for blocks larger than 128KB.",
233 	    ZFEATURE_FLAG_PER_DATASET, large_blocks_deps);
234 }
235