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) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 24 * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 25 * Copyright (c) 2011, 2015 by Delphix. All rights reserved. 26 */ 27 28 #include <sys/zfs_context.h> 29 #include <sys/spa.h> 30 #include <sys/fm/fs/zfs.h> 31 #include <sys/spa_impl.h> 32 #include <sys/nvpair.h> 33 #include <sys/uio.h> 34 #include <sys/fs/zfs.h> 35 #include <sys/vdev_impl.h> 36 #include <sys/zfs_ioctl.h> 37 #include <sys/utsname.h> 38 #include <sys/sunddi.h> 39 #include <sys/zfeature.h> 40 #ifdef _KERNEL 41 #include <sys/kobj.h> 42 #include <sys/zone.h> 43 #endif 44 45 /* 46 * Pool configuration repository. 47 * 48 * Pool configuration is stored as a packed nvlist on the filesystem. By 49 * default, all pools are stored in /etc/zfs/zpool.cache and loaded on boot 50 * (when the ZFS module is loaded). Pools can also have the 'cachefile' 51 * property set that allows them to be stored in an alternate location until 52 * the control of external software. 53 * 54 * For each cache file, we have a single nvlist which holds all the 55 * configuration information. When the module loads, we read this information 56 * from /etc/zfs/zpool.cache and populate the SPA namespace. This namespace is 57 * maintained independently in spa.c. Whenever the namespace is modified, or 58 * the configuration of a pool is changed, we call spa_config_sync(), which 59 * walks through all the active pools and writes the configuration to disk. 60 */ 61 62 static uint64_t spa_config_generation = 1; 63 64 /* 65 * This can be overridden in userland to preserve an alternate namespace for 66 * userland pools when doing testing. 67 */ 68 const char *spa_config_path = ZPOOL_CACHE; 69 70 /* 71 * Called when the module is first loaded, this routine loads the configuration 72 * file into the SPA namespace. It does not actually open or load the pools; it 73 * only populates the namespace. 74 */ 75 void 76 spa_config_load(void) 77 { 78 void *buf = NULL; 79 nvlist_t *nvlist, *child; 80 nvpair_t *nvpair; 81 char *pathname; 82 struct _buf *file; 83 uint64_t fsize; 84 85 /* 86 * Open the configuration file. 87 */ 88 pathname = kmem_alloc(MAXPATHLEN, KM_SLEEP); 89 90 (void) snprintf(pathname, MAXPATHLEN, "%s", spa_config_path); 91 92 file = kobj_open_file(pathname); 93 94 kmem_free(pathname, MAXPATHLEN); 95 96 if (file == (struct _buf *)-1) 97 return; 98 99 if (kobj_get_filesize(file, &fsize) != 0) 100 goto out; 101 102 if (fsize == 0) 103 goto out; 104 105 buf = kmem_alloc(fsize, KM_SLEEP); 106 107 /* 108 * Read the nvlist from the file. 109 */ 110 if (kobj_read_file(file, buf, fsize, 0) < 0) 111 goto out; 112 113 /* 114 * Unpack the nvlist. 115 */ 116 if (nvlist_unpack(buf, fsize, &nvlist, KM_SLEEP) != 0) 117 goto out; 118 119 /* 120 * Iterate over all elements in the nvlist, creating a new spa_t for 121 * each one with the specified configuration. 122 */ 123 mutex_enter(&spa_namespace_lock); 124 nvpair = NULL; 125 while ((nvpair = nvlist_next_nvpair(nvlist, nvpair)) != NULL) { 126 if (nvpair_type(nvpair) != DATA_TYPE_NVLIST) 127 continue; 128 129 child = fnvpair_value_nvlist(nvpair); 130 131 if (spa_lookup(nvpair_name(nvpair)) != NULL) 132 continue; 133 (void) spa_add(nvpair_name(nvpair), child, NULL); 134 } 135 mutex_exit(&spa_namespace_lock); 136 137 nvlist_free(nvlist); 138 139 out: 140 if (buf != NULL) 141 kmem_free(buf, fsize); 142 143 kobj_close_file(file); 144 } 145 146 static void 147 spa_config_clean(nvlist_t *nvl) 148 { 149 nvlist_t **child; 150 nvlist_t *nvroot = NULL; 151 uint_t c, children; 152 153 if (nvlist_lookup_nvlist_array(nvl, ZPOOL_CONFIG_CHILDREN, &child, 154 &children) == 0) { 155 for (c = 0; c < children; c++) 156 spa_config_clean(child[c]); 157 } 158 159 if (nvlist_lookup_nvlist(nvl, ZPOOL_CONFIG_VDEV_TREE, &nvroot) == 0) 160 spa_config_clean(nvroot); 161 162 nvlist_remove(nvl, ZPOOL_CONFIG_VDEV_STATS, DATA_TYPE_UINT64_ARRAY); 163 nvlist_remove(nvl, ZPOOL_CONFIG_SCAN_STATS, DATA_TYPE_UINT64_ARRAY); 164 } 165 166 static int 167 spa_config_write(spa_config_dirent_t *dp, nvlist_t *nvl) 168 { 169 size_t buflen; 170 char *buf; 171 vnode_t *vp; 172 int oflags = FWRITE | FTRUNC | FCREAT | FOFFMAX; 173 char *temp; 174 int err; 175 176 /* 177 * If the nvlist is empty (NULL), then remove the old cachefile. 178 */ 179 if (nvl == NULL) { 180 err = vn_remove(dp->scd_path, UIO_SYSSPACE, RMFILE); 181 return (err); 182 } 183 184 /* 185 * Pack the configuration into a buffer. 186 */ 187 buf = fnvlist_pack(nvl, &buflen); 188 temp = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 189 190 /* 191 * Write the configuration to disk. We need to do the traditional 192 * 'write to temporary file, sync, move over original' to make sure we 193 * always have a consistent view of the data. 194 */ 195 (void) snprintf(temp, MAXPATHLEN, "%s.tmp", dp->scd_path); 196 197 err = vn_open(temp, UIO_SYSSPACE, oflags, 0644, &vp, CRCREAT, 0); 198 if (err == 0) { 199 err = vn_rdwr(UIO_WRITE, vp, buf, buflen, 0, UIO_SYSSPACE, 200 0, RLIM64_INFINITY, kcred, NULL); 201 if (err == 0) 202 err = VOP_FSYNC(vp, FSYNC, kcred, NULL); 203 if (err == 0) 204 err = vn_rename(temp, dp->scd_path, UIO_SYSSPACE); 205 (void) VOP_CLOSE(vp, oflags, 1, 0, kcred, NULL); 206 } 207 208 (void) vn_remove(temp, UIO_SYSSPACE, RMFILE); 209 210 fnvlist_pack_free(buf, buflen); 211 kmem_free(temp, MAXPATHLEN); 212 return (err); 213 } 214 215 /* 216 * Synchronize pool configuration to disk. This must be called with the 217 * namespace lock held. Synchronizing the pool cache is typically done after 218 * the configuration has been synced to the MOS. This exposes a window where 219 * the MOS config will have been updated but the cache file has not. If 220 * the system were to crash at that instant then the cached config may not 221 * contain the correct information to open the pool and an explicity import 222 * would be required. 223 */ 224 void 225 spa_config_sync(spa_t *target, boolean_t removing, boolean_t postsysevent) 226 { 227 spa_config_dirent_t *dp, *tdp; 228 nvlist_t *nvl; 229 boolean_t ccw_failure; 230 int error; 231 232 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 233 234 if (rootdir == NULL || !(spa_mode_global & FWRITE)) 235 return; 236 237 /* 238 * Iterate over all cachefiles for the pool, past or present. When the 239 * cachefile is changed, the new one is pushed onto this list, allowing 240 * us to update previous cachefiles that no longer contain this pool. 241 */ 242 ccw_failure = B_FALSE; 243 for (dp = list_head(&target->spa_config_list); dp != NULL; 244 dp = list_next(&target->spa_config_list, dp)) { 245 spa_t *spa = NULL; 246 if (dp->scd_path == NULL) 247 continue; 248 249 /* 250 * Iterate over all pools, adding any matching pools to 'nvl'. 251 */ 252 nvl = NULL; 253 while ((spa = spa_next(spa)) != NULL) { 254 nvlist_t *nvroot = NULL; 255 /* 256 * Skip over our own pool if we're about to remove 257 * ourselves from the spa namespace or any pool that 258 * is readonly. Since we cannot guarantee that a 259 * readonly pool would successfully import upon reboot, 260 * we don't allow them to be written to the cache file. 261 */ 262 if ((spa == target && removing) || 263 (spa_state(spa) == POOL_STATE_ACTIVE && 264 !spa_writeable(spa))) 265 continue; 266 267 mutex_enter(&spa->spa_props_lock); 268 tdp = list_head(&spa->spa_config_list); 269 if (spa->spa_config == NULL || 270 tdp->scd_path == NULL || 271 strcmp(tdp->scd_path, dp->scd_path) != 0) { 272 mutex_exit(&spa->spa_props_lock); 273 continue; 274 } 275 276 if (nvl == NULL) 277 nvl = fnvlist_alloc(); 278 279 fnvlist_add_nvlist(nvl, spa->spa_name, 280 spa->spa_config); 281 mutex_exit(&spa->spa_props_lock); 282 283 if (nvlist_lookup_nvlist(nvl, spa->spa_name, &nvroot) == 0) 284 spa_config_clean(nvroot); 285 } 286 287 error = spa_config_write(dp, nvl); 288 if (error != 0) 289 ccw_failure = B_TRUE; 290 nvlist_free(nvl); 291 } 292 293 if (ccw_failure) { 294 /* 295 * Keep trying so that configuration data is 296 * written if/when any temporary filesystem 297 * resource issues are resolved. 298 */ 299 if (target->spa_ccw_fail_time == 0) { 300 zfs_ereport_post(FM_EREPORT_ZFS_CONFIG_CACHE_WRITE, 301 target, NULL, NULL, 0, 0); 302 } 303 target->spa_ccw_fail_time = gethrtime(); 304 spa_async_request(target, SPA_ASYNC_CONFIG_UPDATE); 305 } else { 306 /* 307 * Do not rate limit future attempts to update 308 * the config cache. 309 */ 310 target->spa_ccw_fail_time = 0; 311 } 312 313 /* 314 * Remove any config entries older than the current one. 315 */ 316 dp = list_head(&target->spa_config_list); 317 while ((tdp = list_next(&target->spa_config_list, dp)) != NULL) { 318 list_remove(&target->spa_config_list, tdp); 319 if (tdp->scd_path != NULL) 320 spa_strfree(tdp->scd_path); 321 kmem_free(tdp, sizeof (spa_config_dirent_t)); 322 } 323 324 spa_config_generation++; 325 326 if (postsysevent) 327 spa_event_notify(target, NULL, ESC_ZFS_CONFIG_SYNC); 328 } 329 330 /* 331 * Sigh. Inside a local zone, we don't have access to /etc/zfs/zpool.cache, 332 * and we don't want to allow the local zone to see all the pools anyway. 333 * So we have to invent the ZFS_IOC_CONFIG ioctl to grab the configuration 334 * information for all pool visible within the zone. 335 */ 336 nvlist_t * 337 spa_all_configs(uint64_t *generation) 338 { 339 nvlist_t *pools; 340 spa_t *spa = NULL; 341 342 if (*generation == spa_config_generation) 343 return (NULL); 344 345 pools = fnvlist_alloc(); 346 347 mutex_enter(&spa_namespace_lock); 348 while ((spa = spa_next(spa)) != NULL) { 349 if (INGLOBALZONE(curthread) || 350 zone_dataset_visible(spa_name(spa), NULL)) { 351 mutex_enter(&spa->spa_props_lock); 352 fnvlist_add_nvlist(pools, spa_name(spa), 353 spa->spa_config); 354 mutex_exit(&spa->spa_props_lock); 355 } 356 } 357 *generation = spa_config_generation; 358 mutex_exit(&spa_namespace_lock); 359 360 return (pools); 361 } 362 363 void 364 spa_config_set(spa_t *spa, nvlist_t *config) 365 { 366 mutex_enter(&spa->spa_props_lock); 367 nvlist_free(spa->spa_config); 368 spa->spa_config = config; 369 mutex_exit(&spa->spa_props_lock); 370 } 371 372 /* 373 * Generate the pool's configuration based on the current in-core state. 374 * 375 * We infer whether to generate a complete config or just one top-level config 376 * based on whether vd is the root vdev. 377 */ 378 nvlist_t * 379 spa_config_generate(spa_t *spa, vdev_t *vd, uint64_t txg, int getstats) 380 { 381 nvlist_t *config, *nvroot; 382 vdev_t *rvd = spa->spa_root_vdev; 383 unsigned long hostid = 0; 384 boolean_t locked = B_FALSE; 385 uint64_t split_guid; 386 387 if (vd == NULL) { 388 vd = rvd; 389 locked = B_TRUE; 390 spa_config_enter(spa, SCL_CONFIG | SCL_STATE, FTAG, RW_READER); 391 } 392 393 ASSERT(spa_config_held(spa, SCL_CONFIG | SCL_STATE, RW_READER) == 394 (SCL_CONFIG | SCL_STATE)); 395 396 /* 397 * If txg is -1, report the current value of spa->spa_config_txg. 398 */ 399 if (txg == -1ULL) 400 txg = spa->spa_config_txg; 401 402 config = fnvlist_alloc(); 403 404 fnvlist_add_uint64(config, ZPOOL_CONFIG_VERSION, spa_version(spa)); 405 fnvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME, spa_name(spa)); 406 fnvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE, spa_state(spa)); 407 fnvlist_add_uint64(config, ZPOOL_CONFIG_POOL_TXG, txg); 408 fnvlist_add_uint64(config, ZPOOL_CONFIG_POOL_GUID, spa_guid(spa)); 409 if (spa->spa_comment != NULL) { 410 fnvlist_add_string(config, ZPOOL_CONFIG_COMMENT, 411 spa->spa_comment); 412 } 413 414 #ifdef _KERNEL 415 hostid = zone_get_hostid(NULL); 416 #else /* _KERNEL */ 417 /* 418 * We're emulating the system's hostid in userland, so we can't use 419 * zone_get_hostid(). 420 */ 421 (void) ddi_strtoul(hw_serial, NULL, 10, &hostid); 422 #endif /* _KERNEL */ 423 if (hostid != 0) { 424 fnvlist_add_uint64(config, ZPOOL_CONFIG_HOSTID, hostid); 425 } 426 fnvlist_add_string(config, ZPOOL_CONFIG_HOSTNAME, utsname.nodename); 427 428 int config_gen_flags = 0; 429 if (vd != rvd) { 430 fnvlist_add_uint64(config, ZPOOL_CONFIG_TOP_GUID, 431 vd->vdev_top->vdev_guid); 432 fnvlist_add_uint64(config, ZPOOL_CONFIG_GUID, 433 vd->vdev_guid); 434 if (vd->vdev_isspare) { 435 fnvlist_add_uint64(config, 436 ZPOOL_CONFIG_IS_SPARE, 1ULL); 437 } 438 if (vd->vdev_islog) { 439 fnvlist_add_uint64(config, 440 ZPOOL_CONFIG_IS_LOG, 1ULL); 441 } 442 vd = vd->vdev_top; /* label contains top config */ 443 } else { 444 /* 445 * Only add the (potentially large) split information 446 * in the mos config, and not in the vdev labels 447 */ 448 if (spa->spa_config_splitting != NULL) 449 fnvlist_add_nvlist(config, ZPOOL_CONFIG_SPLIT, 450 spa->spa_config_splitting); 451 fnvlist_add_boolean(config, 452 ZPOOL_CONFIG_HAS_PER_VDEV_ZAPS); 453 454 config_gen_flags |= VDEV_CONFIG_MOS; 455 } 456 457 /* 458 * Add the top-level config. We even add this on pools which 459 * don't support holes in the namespace. 460 */ 461 vdev_top_config_generate(spa, config); 462 463 /* 464 * If we're splitting, record the original pool's guid. 465 */ 466 if (spa->spa_config_splitting != NULL && 467 nvlist_lookup_uint64(spa->spa_config_splitting, 468 ZPOOL_CONFIG_SPLIT_GUID, &split_guid) == 0) { 469 fnvlist_add_uint64(config, ZPOOL_CONFIG_SPLIT_GUID, 470 split_guid); 471 } 472 473 nvroot = vdev_config_generate(spa, vd, getstats, config_gen_flags); 474 fnvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, nvroot); 475 nvlist_free(nvroot); 476 477 /* 478 * Store what's necessary for reading the MOS in the label. 479 */ 480 fnvlist_add_nvlist(config, ZPOOL_CONFIG_FEATURES_FOR_READ, 481 spa->spa_label_features); 482 483 if (getstats && spa_load_state(spa) == SPA_LOAD_NONE) { 484 ddt_histogram_t *ddh; 485 ddt_stat_t *dds; 486 ddt_object_t *ddo; 487 488 ddh = kmem_zalloc(sizeof (ddt_histogram_t), KM_SLEEP); 489 ddt_get_dedup_histogram(spa, ddh); 490 fnvlist_add_uint64_array(config, 491 ZPOOL_CONFIG_DDT_HISTOGRAM, 492 (uint64_t *)ddh, sizeof (*ddh) / sizeof (uint64_t)); 493 kmem_free(ddh, sizeof (ddt_histogram_t)); 494 495 ddo = kmem_zalloc(sizeof (ddt_object_t), KM_SLEEP); 496 ddt_get_dedup_object_stats(spa, ddo); 497 fnvlist_add_uint64_array(config, 498 ZPOOL_CONFIG_DDT_OBJ_STATS, 499 (uint64_t *)ddo, sizeof (*ddo) / sizeof (uint64_t)); 500 kmem_free(ddo, sizeof (ddt_object_t)); 501 502 dds = kmem_zalloc(sizeof (ddt_stat_t), KM_SLEEP); 503 ddt_get_dedup_stats(spa, dds); 504 fnvlist_add_uint64_array(config, 505 ZPOOL_CONFIG_DDT_STATS, 506 (uint64_t *)dds, sizeof (*dds) / sizeof (uint64_t)); 507 kmem_free(dds, sizeof (ddt_stat_t)); 508 } 509 510 if (locked) 511 spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG); 512 513 return (config); 514 } 515 516 /* 517 * Update all disk labels, generate a fresh config based on the current 518 * in-core state, and sync the global config cache (do not sync the config 519 * cache if this is a booting rootpool). 520 */ 521 void 522 spa_config_update(spa_t *spa, int what) 523 { 524 vdev_t *rvd = spa->spa_root_vdev; 525 uint64_t txg; 526 int c; 527 528 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 529 530 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER); 531 txg = spa_last_synced_txg(spa) + 1; 532 if (what == SPA_CONFIG_UPDATE_POOL) { 533 vdev_config_dirty(rvd); 534 } else { 535 /* 536 * If we have top-level vdevs that were added but have 537 * not yet been prepared for allocation, do that now. 538 * (It's safe now because the config cache is up to date, 539 * so it will be able to translate the new DVAs.) 540 * See comments in spa_vdev_add() for full details. 541 */ 542 for (c = 0; c < rvd->vdev_children; c++) { 543 vdev_t *tvd = rvd->vdev_child[c]; 544 if (tvd->vdev_ms_array == 0) { 545 vdev_ashift_optimize(tvd); 546 vdev_metaslab_set_size(tvd); 547 } 548 vdev_expand(tvd, txg); 549 } 550 } 551 spa_config_exit(spa, SCL_ALL, FTAG); 552 553 /* 554 * Wait for the mosconfig to be regenerated and synced. 555 */ 556 txg_wait_synced(spa->spa_dsl_pool, txg); 557 558 /* 559 * Update the global config cache to reflect the new mosconfig. 560 */ 561 spa_config_sync(spa, B_FALSE, what != SPA_CONFIG_UPDATE_POOL); 562 563 if (what == SPA_CONFIG_UPDATE_POOL) 564 spa_config_update(spa, SPA_CONFIG_UPDATE_VDEVS); 565 } 566
Indexes created Thu Jun 11 00:25:07 UTC 2026