module/zcommon/zfeature_common.c

   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  */
  28
  29 #ifndef _KERNEL
  30 #include <errno.h>
  31 #include <string.h>
  32 #include <sys/stat.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 <sys/zfs_sysfs.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_guid(const char *guid, 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 (!feature->fi_zfs_mod_supported)
 111                         continue;
 112                 if (strcmp(guid, feature->fi_guid) == 0) {
 113                         if (res != NULL)
 114                                 *res = i;
 115                         return (0);
 116                 }
 117         }
 118
 119         return (ENOENT);
 120 }
 121
 122 int
 123 zfeature_lookup_name(const char *name, spa_feature_t *res)
 124 {
 125         for (spa_feature_t i = 0; i < SPA_FEATURES; i++) {
 126                 zfeature_info_t *feature = &spa_feature_table[i];
 127                 if (!feature->fi_zfs_mod_supported)
 128                         continue;
 129                 if (strcmp(name, feature->fi_uname) == 0) {
 130                         if (res != NULL)
 131                                 *res = i;
 132                         return (0);
 133                 }
 134         }
 135
 136         return (ENOENT);
 137 }
 138
 139 boolean_t
 140 zfeature_depends_on(spa_feature_t fid, spa_feature_t check)
 141 {
 142         zfeature_info_t *feature = &spa_feature_table[fid];
 143
 144         for (int i = 0; feature->fi_depends[i] != SPA_FEATURE_NONE; i++) {
 145                 if (feature->fi_depends[i] == check)
 146                         return (B_TRUE);
 147         }
 148         return (B_FALSE);
 149 }
 150
 151 static boolean_t
 152 deps_contains_feature(const spa_feature_t *deps, const spa_feature_t feature)
 153 {
 154         for (int i = 0; deps[i] != SPA_FEATURE_NONE; i++)
 155                 if (deps[i] == feature)
 156                         return (B_TRUE);
 157
 158         return (B_FALSE);
 159 }
 160
 161 static boolean_t
 162 zfs_mod_supported_feature(const char *name)
 163 {
 164         /*
 165          * The zfs module spa_feature_table[], whether in-kernel or in
 166          * libzpool, always supports all the features. libzfs needs to
 167          * query the running module, via sysfs, to determine which
 168          * features are supported.
 169          */
 170 #if defined(_KERNEL) || defined(LIB_ZPOOL_BUILD)
 171         return (B_TRUE);
 172 #else
 173         struct stat64 statbuf;
 174         char *path;
 175         boolean_t supported = B_FALSE;
 176         int len;
 177
 178         len = asprintf(&path, "%s/%s/%s", ZFS_SYSFS_DIR,
 179             ZFS_SYSFS_POOL_FEATURES, name);
 180
 181         if (len > 0) {
 182                 supported = !!(stat64(path, &statbuf) == 0);
 183                 free(path);
 184         }
 185         return (supported);
 186 #endif
 187 }
 188
 189 static void
 190 zfeature_register(spa_feature_t fid, const char *guid, const char *name,
 191     const char *desc, zfeature_flags_t flags, const spa_feature_t *deps)
 192 {
 193         zfeature_info_t *feature = &spa_feature_table[fid];
 194         static spa_feature_t nodeps[] = { SPA_FEATURE_NONE };
 195
 196         ASSERT(name != NULL);
 197         ASSERT(desc != NULL);
 198         ASSERT((flags & ZFEATURE_FLAG_READONLY_COMPAT) == 0 ||
 199             (flags & ZFEATURE_FLAG_MOS) == 0);
 200         ASSERT3U(fid, <, SPA_FEATURES);
 201         ASSERT(zfeature_is_valid_guid(guid));
 202
 203         if (deps == NULL)
 204                 deps = nodeps;
 205
 206         VERIFY(((flags & ZFEATURE_FLAG_PER_DATASET) == 0) ||
 207             (deps_contains_feature(deps, SPA_FEATURE_EXTENSIBLE_DATASET)));
 208
 209         feature->fi_feature = fid;
 210         feature->fi_guid = guid;
 211         feature->fi_uname = name;
 212         feature->fi_desc = desc;
 213         feature->fi_flags = flags;
 214         feature->fi_depends = deps;
 215         feature->fi_zfs_mod_supported = zfs_mod_supported_feature(guid);
 216 }
 217
 218 void
 219 zpool_feature_init(void)
 220 {
 221         zfeature_register(SPA_FEATURE_ASYNC_DESTROY,
 222             "com.delphix:async_destroy", "async_destroy",
 223             "Destroy filesystems asynchronously.",
 224             ZFEATURE_FLAG_READONLY_COMPAT, NULL);
 225
 226         zfeature_register(SPA_FEATURE_EMPTY_BPOBJ,
 227             "com.delphix:empty_bpobj", "empty_bpobj",
 228             "Snapshots use less space.",
 229             ZFEATURE_FLAG_READONLY_COMPAT, NULL);
 230
 231         zfeature_register(SPA_FEATURE_LZ4_COMPRESS,
 232             "org.illumos:lz4_compress", "lz4_compress",
 233             "LZ4 compression algorithm support.",
 234             ZFEATURE_FLAG_ACTIVATE_ON_ENABLE, NULL);
 235
 236         zfeature_register(SPA_FEATURE_MULTI_VDEV_CRASH_DUMP,
 237             "com.joyent:multi_vdev_crash_dump", "multi_vdev_crash_dump",
 238             "Crash dumps to multiple vdev pools.",
 239             0, NULL);
 240
 241         zfeature_register(SPA_FEATURE_SPACEMAP_HISTOGRAM,
 242             "com.delphix:spacemap_histogram", "spacemap_histogram",
 243             "Spacemaps maintain space histograms.",
 244             ZFEATURE_FLAG_READONLY_COMPAT, NULL);
 245
 246         zfeature_register(SPA_FEATURE_ENABLED_TXG,
 247             "com.delphix:enabled_txg", "enabled_txg",
 248             "Record txg at which a feature is enabled",
 249             ZFEATURE_FLAG_READONLY_COMPAT, NULL);
 250
 251         {
 252         static const spa_feature_t hole_birth_deps[] = {
 253                 SPA_FEATURE_ENABLED_TXG,
 254                 SPA_FEATURE_NONE
 255         };
 256         zfeature_register(SPA_FEATURE_HOLE_BIRTH,
 257             "com.delphix:hole_birth", "hole_birth",
 258             "Retain hole birth txg for more precise zfs send",
 259             ZFEATURE_FLAG_MOS | ZFEATURE_FLAG_ACTIVATE_ON_ENABLE,
 260             hole_birth_deps);
 261         }
 262
 263         zfeature_register(SPA_FEATURE_POOL_CHECKPOINT,
 264             "com.delphix:zpool_checkpoint", "zpool_checkpoint",
 265             "Pool state can be checkpointed, allowing rewind later.",
 266             ZFEATURE_FLAG_READONLY_COMPAT, NULL);
 267
 268         zfeature_register(SPA_FEATURE_SPACEMAP_V2,
 269             "com.delphix:spacemap_v2", "spacemap_v2",
 270             "Space maps representing large segments are more efficient.",
 271             ZFEATURE_FLAG_READONLY_COMPAT | ZFEATURE_FLAG_ACTIVATE_ON_ENABLE,
 272             NULL);
 273
 274         zfeature_register(SPA_FEATURE_EXTENSIBLE_DATASET,
 275             "com.delphix:extensible_dataset", "extensible_dataset",
 276             "Enhanced dataset functionality, used by other features.",
 277             0, NULL);
 278
 279         {
 280         static const spa_feature_t bookmarks_deps[] = {
 281                 SPA_FEATURE_EXTENSIBLE_DATASET,
 282                 SPA_FEATURE_NONE
 283         };
 284
 285         zfeature_register(SPA_FEATURE_BOOKMARKS,
 286             "com.delphix:bookmarks", "bookmarks",
 287             "\"zfs bookmark\" command",
 288             ZFEATURE_FLAG_READONLY_COMPAT, bookmarks_deps);
 289         }
 290
 291         {
 292         static const spa_feature_t filesystem_limits_deps[] = {
 293                 SPA_FEATURE_EXTENSIBLE_DATASET,
 294                 SPA_FEATURE_NONE
 295         };
 296         zfeature_register(SPA_FEATURE_FS_SS_LIMIT,
 297             "com.joyent:filesystem_limits", "filesystem_limits",
 298             "Filesystem and snapshot limits.",
 299             ZFEATURE_FLAG_READONLY_COMPAT, filesystem_limits_deps);
 300         }
 301
 302         zfeature_register(SPA_FEATURE_EMBEDDED_DATA,
 303             "com.delphix:embedded_data", "embedded_data",
 304             "Blocks which compress very well use even less space.",
 305             ZFEATURE_FLAG_MOS | ZFEATURE_FLAG_ACTIVATE_ON_ENABLE,
 306             NULL);
 307
 308         {
 309         static const spa_feature_t large_blocks_deps[] = {
 310                 SPA_FEATURE_EXTENSIBLE_DATASET,
 311                 SPA_FEATURE_NONE
 312         };
 313         zfeature_register(SPA_FEATURE_LARGE_BLOCKS,
 314             "org.open-zfs:large_blocks", "large_blocks",
 315             "Support for blocks larger than 128KB.",
 316             ZFEATURE_FLAG_PER_DATASET, large_blocks_deps);
 317         }
 318
 319         {
 320         static const spa_feature_t large_dnode_deps[] = {
 321                 SPA_FEATURE_EXTENSIBLE_DATASET,
 322                 SPA_FEATURE_NONE
 323         };
 324         zfeature_register(SPA_FEATURE_LARGE_DNODE,
 325             "org.zfsonlinux:large_dnode", "large_dnode",
 326             "Variable on-disk size of dnodes.",
 327             ZFEATURE_FLAG_PER_DATASET, large_dnode_deps);
 328         }
 329
 330         {
 331         static const spa_feature_t sha512_deps[] = {
 332                 SPA_FEATURE_EXTENSIBLE_DATASET,
 333                 SPA_FEATURE_NONE
 334         };
 335         zfeature_register(SPA_FEATURE_SHA512,
 336             "org.illumos:sha512", "sha512",
 337             "SHA-512/256 hash algorithm.",
 338             ZFEATURE_FLAG_PER_DATASET, sha512_deps);
 339         }
 340         {
 341         static const spa_feature_t skein_deps[] = {
 342                 SPA_FEATURE_EXTENSIBLE_DATASET,
 343                 SPA_FEATURE_NONE
 344         };
 345         zfeature_register(SPA_FEATURE_SKEIN,
 346             "org.illumos:skein", "skein",
 347             "Skein hash algorithm.",
 348             ZFEATURE_FLAG_PER_DATASET, skein_deps);
 349         }
 350
 351         {
 352         static const spa_feature_t edonr_deps[] = {
 353                 SPA_FEATURE_EXTENSIBLE_DATASET,
 354                 SPA_FEATURE_NONE
 355         };
 356         zfeature_register(SPA_FEATURE_EDONR,
 357             "org.illumos:edonr", "edonr",
 358             "Edon-R hash algorithm.",
 359             ZFEATURE_FLAG_PER_DATASET, edonr_deps);
 360         }
 361         zfeature_register(SPA_FEATURE_DEVICE_REMOVAL,
 362             "com.delphix:device_removal", "device_removal",
 363             "Top-level vdevs can be removed, reducing logical pool size.",
 364             ZFEATURE_FLAG_MOS, NULL);
 365         {
 366         static const spa_feature_t obsolete_counts_deps[] = {
 367                 SPA_FEATURE_EXTENSIBLE_DATASET,
 368                 SPA_FEATURE_DEVICE_REMOVAL,
 369                 SPA_FEATURE_NONE
 370         };
 371         zfeature_register(SPA_FEATURE_OBSOLETE_COUNTS,
 372             "com.delphix:obsolete_counts", "obsolete_counts",
 373             "Reduce memory used by removed devices when their blocks are "
 374             "freed or remapped.",
 375             ZFEATURE_FLAG_READONLY_COMPAT, obsolete_counts_deps);
 376         }
 377         {
 378         static const spa_feature_t userobj_accounting_deps[] = {
 379                 SPA_FEATURE_EXTENSIBLE_DATASET,
 380                 SPA_FEATURE_NONE
 381         };
 382         zfeature_register(SPA_FEATURE_USEROBJ_ACCOUNTING,
 383             "org.zfsonlinux:userobj_accounting", "userobj_accounting",
 384             "User/Group object accounting.",
 385             ZFEATURE_FLAG_READONLY_COMPAT | ZFEATURE_FLAG_PER_DATASET,
 386             userobj_accounting_deps);
 387         }
 388
 389         {
 390         static const spa_feature_t encryption_deps[] = {
 391                 SPA_FEATURE_EXTENSIBLE_DATASET,
 392                 SPA_FEATURE_NONE
 393         };
 394         zfeature_register(SPA_FEATURE_ENCRYPTION,
 395             "com.datto:encryption", "encryption",
 396             "Support for dataset level encryption",
 397             ZFEATURE_FLAG_PER_DATASET, encryption_deps);
 398         }
 399
 400         {
 401         static const spa_feature_t project_quota_deps[] = {
 402                 SPA_FEATURE_EXTENSIBLE_DATASET,
 403                 SPA_FEATURE_NONE
 404         };
 405         zfeature_register(SPA_FEATURE_PROJECT_QUOTA,
 406             "org.zfsonlinux:project_quota", "project_quota",
 407             "space/object accounting based on project ID.",
 408             ZFEATURE_FLAG_READONLY_COMPAT | ZFEATURE_FLAG_PER_DATASET,
 409             project_quota_deps);
 410         }
 411 }
 412
 413 #if defined(_KERNEL)
 414 EXPORT_SYMBOL(zfeature_lookup_guid);
 415 EXPORT_SYMBOL(zfeature_lookup_name);
 416 EXPORT_SYMBOL(zfeature_is_supported);
 417 EXPORT_SYMBOL(zfeature_is_valid_guid);
 418 EXPORT_SYMBOL(zfeature_depends_on);
 419 EXPORT_SYMBOL(zpool_feature_init);
 420 EXPORT_SYMBOL(spa_feature_table);
 421 #endif