xref: /titanic_41/usr/src/common/zfs/zfeature_common.c (revision b59b3655028aeb11832ad679eb5c2577c2b75235)
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  * 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 	    c == (after_colon ? '_' : '.'));
61 }
62 
63 /*
64  * Every feature guid must contain exactly one colon which separates a reverse
65  * dns organization name from the feature's "short" name (e.g.
66  * "com.company:feature_name").
67  */
68 boolean_t
69 zfeature_is_valid_guid(const char *name)
70 {
71 	int i;
72 	boolean_t has_colon = B_FALSE;
73 
74 	i = 0;
75 	while (name[i] != '\0') {
76 		char c = name[i++];
77 		if (c == ':') {
78 			if (has_colon)
79 				return (B_FALSE);
80 			has_colon = B_TRUE;
81 			continue;
82 		}
83 		if (!valid_char(c, has_colon))
84 			return (B_FALSE);
85 	}
86 
87 	return (has_colon);
88 }
89 
90 boolean_t
91 zfeature_is_supported(const char *guid)
92 {
93 	if (zfeature_checks_disable)
94 		return (B_TRUE);
95 
96 	for (spa_feature_t i = 0; i < SPA_FEATURES; i++) {
97 		zfeature_info_t *feature = &spa_feature_table[i];
98 		if (strcmp(guid, feature->fi_guid) == 0)
99 			return (B_TRUE);
100 	}
101 	return (B_FALSE);
102 }
103 
104 int
105 zfeature_lookup_name(const char *name, spa_feature_t *res)
106 {
107 	for (spa_feature_t i = 0; i < SPA_FEATURES; i++) {
108 		zfeature_info_t *feature = &spa_feature_table[i];
109 		if (strcmp(name, feature->fi_uname) == 0) {
110 			if (res != NULL)
111 				*res = i;
112 			return (0);
113 		}
114 	}
115 
116 	return (ENOENT);
117 }
118 
119 boolean_t
120 zfeature_depends_on(spa_feature_t fid, spa_feature_t check) {
121 	zfeature_info_t *feature = &spa_feature_table[fid];
122 
123 	for (int i = 0; feature->fi_depends[i] != SPA_FEATURE_NONE; i++) {
124 		if (feature->fi_depends[i] == check)
125 			return (B_TRUE);
126 	}
127 	return (B_FALSE);
128 }
129 
130 static void
131 zfeature_register(spa_feature_t fid, const char *guid, const char *name,
132     const char *desc, boolean_t readonly, boolean_t mos,
133     boolean_t activate_on_enable, 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(!readonly || !mos);
141 	ASSERT3U(fid, <, SPA_FEATURES);
142 	ASSERT(zfeature_is_valid_guid(guid));
143 
144 	if (deps == NULL)
145 		deps = nodeps;
146 
147 	feature->fi_feature = fid;
148 	feature->fi_guid = guid;
149 	feature->fi_uname = name;
150 	feature->fi_desc = desc;
151 	feature->fi_can_readonly = readonly;
152 	feature->fi_mos = mos;
153 	feature->fi_activate_on_enable = activate_on_enable;
154 	feature->fi_depends = deps;
155 }
156 
157 void
158 zpool_feature_init(void)
159 {
160 	zfeature_register(SPA_FEATURE_ASYNC_DESTROY,
161 	    "com.delphix:async_destroy", "async_destroy",
162 	    "Destroy filesystems asynchronously.", B_TRUE, B_FALSE,
163 	    B_FALSE, NULL);
164 
165 	zfeature_register(SPA_FEATURE_EMPTY_BPOBJ,
166 	    "com.delphix:empty_bpobj", "empty_bpobj",
167 	    "Snapshots use less space.", B_TRUE, B_FALSE,
168 	    B_FALSE, NULL);
169 
170 	zfeature_register(SPA_FEATURE_LZ4_COMPRESS,
171 	    "org.illumos:lz4_compress", "lz4_compress",
172 	    "LZ4 compression algorithm support.", B_FALSE, B_FALSE,
173 	    B_TRUE, NULL);
174 
175 	zfeature_register(SPA_FEATURE_MULTI_VDEV_CRASH_DUMP,
176 	    "com.joyent:multi_vdev_crash_dump", "multi_vdev_crash_dump",
177 	    "Crash dumps to multiple vdev pools.", B_FALSE, B_FALSE,
178 	    B_FALSE, NULL);
179 
180 	zfeature_register(SPA_FEATURE_SPACEMAP_HISTOGRAM,
181 	    "com.delphix:spacemap_histogram", "spacemap_histogram",
182 	    "Spacemaps maintain space histograms.", B_TRUE, B_FALSE,
183 	    B_FALSE, NULL);
184 
185 	zfeature_register(SPA_FEATURE_ENABLED_TXG,
186 	    "com.delphix:enabled_txg", "enabled_txg",
187 	    "Record txg at which a feature is enabled", B_TRUE, B_FALSE,
188 	    B_FALSE, NULL);
189 
190 	static spa_feature_t hole_birth_deps[] = { SPA_FEATURE_ENABLED_TXG,
191 	    SPA_FEATURE_NONE };
192 	zfeature_register(SPA_FEATURE_HOLE_BIRTH,
193 	    "com.delphix:hole_birth", "hole_birth",
194 	    "Retain hole birth txg for more precise zfs send",
195 	    B_FALSE, B_TRUE, B_TRUE, 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 	    B_FALSE, B_FALSE, B_FALSE, 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 	    B_TRUE, B_FALSE, B_FALSE, 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.", B_TRUE, B_FALSE, B_FALSE,
218 	    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 	    B_FALSE, B_TRUE, B_TRUE, NULL);
224 }
225