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.
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.
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]
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, 2018 by Delphix. All rights reserved.
26 * Copyright 2017 Joyent, Inc.
31 #include <sys/fm/fs/zfs.h>
32 #include <sys/spa_impl.h>
33 #include <sys/nvpair.h>
35 #include <sys/fs/zfs.h>
36 #include <sys/vdev_impl.h>
37 #include <sys/zfs_ioctl.h>
38 #include <sys/systeminfo.h>
39 #include <sys/sunddi.h>
40 #include <sys/zfeature.h>
41 #include <sys/zfs_file.h>
47 * Pool configuration repository.
49 * Pool configuration is stored as a packed nvlist on the filesystem. By
50 * default, all pools are stored in /etc/zfs/zpool.cache and loaded on boot
51 * (when the ZFS module is loaded). Pools can also have the 'cachefile'
52 * property set that allows them to be stored in an alternate location until
53 * the control of external software.
55 * For each cache file, we have a single nvlist which holds all the
56 * configuration information. When the module loads, we read this information
57 * from /etc/zfs/zpool.cache and populate the SPA namespace. This namespace is
58 * maintained independently in spa.c. Whenever the namespace is modified, or
59 * the configuration of a pool is changed, we call spa_write_cachefile(), which
60 * walks through all the active pools and writes the configuration to disk.
63 static uint64_t spa_config_generation = 1;
66 * This can be overridden in userland to preserve an alternate namespace for
67 * userland pools when doing testing.
69 char *spa_config_path = ZPOOL_CACHE;
70 int zfs_autoimport_disable = 1;
73 * Called when the module is first loaded, this routine loads the configuration
74 * file into the SPA namespace. It does not actually open or load the pools; it
75 * only populates the namespace.
81 nvlist_t *nvlist, *child;
90 if (zfs_autoimport_disable)
95 * Open the configuration file.
97 pathname = kmem_alloc(MAXPATHLEN, KM_SLEEP);
99 (void) snprintf(pathname, MAXPATHLEN, "%s", spa_config_path);
101 err = zfs_file_open(pathname, O_RDONLY, 0, &fp);
105 err = zfs_file_open(ZPOOL_CACHE_BOOT, O_RDONLY, 0, &fp);
107 kmem_free(pathname, MAXPATHLEN);
112 if (zfs_file_getattr(fp, &zfa))
115 fsize = zfa.zfa_size;
116 buf = kmem_alloc(fsize, KM_SLEEP);
119 * Read the nvlist from the file.
121 if (zfs_file_read(fp, buf, fsize, NULL) < 0)
127 if (nvlist_unpack(buf, fsize, &nvlist, KM_SLEEP) != 0)
131 * Iterate over all elements in the nvlist, creating a new spa_t for
132 * each one with the specified configuration.
134 mutex_enter(&spa_namespace_lock);
136 while ((nvpair = nvlist_next_nvpair(nvlist, nvpair)) != NULL) {
137 if (nvpair_type(nvpair) != DATA_TYPE_NVLIST)
140 child = fnvpair_value_nvlist(nvpair);
142 if (spa_lookup(nvpair_name(nvpair)) != NULL)
144 (void) spa_add(nvpair_name(nvpair), child, NULL);
146 mutex_exit(&spa_namespace_lock);
152 kmem_free(buf, fsize);
158 spa_config_remove(spa_config_dirent_t *dp)
163 * Remove the cache file. If zfs_file_unlink() in not supported by the
164 * platform fallback to truncating the file which is functionally
167 error = zfs_file_unlink(dp->scd_path);
168 if (error == EOPNOTSUPP) {
169 int flags = O_RDWR | O_TRUNC;
172 error = zfs_file_open(dp->scd_path, flags, 0644, &fp);
174 (void) zfs_file_fsync(fp, O_SYNC);
175 (void) zfs_file_close(fp);
183 spa_config_write(spa_config_dirent_t *dp, nvlist_t *nvl)
187 int oflags = O_RDWR | O_TRUNC | O_CREAT | O_LARGEFILE;
193 * If the nvlist is empty (NULL), then remove the old cachefile.
196 err = spa_config_remove(dp);
204 * Pack the configuration into a buffer.
206 buf = fnvlist_pack(nvl, &buflen);
207 temp = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
210 * Write the configuration to disk. Due to the complexity involved
211 * in performing a rename and remove from within the kernel the file
212 * is instead truncated and overwritten in place. This way we always
213 * have a consistent view of the data or a zero length file.
215 err = zfs_file_open(dp->scd_path, oflags, 0644, &fp);
217 err = zfs_file_write(fp, buf, buflen, NULL);
219 err = zfs_file_fsync(fp, O_SYNC);
223 (void) spa_config_remove(dp);
225 fnvlist_pack_free(buf, buflen);
226 kmem_free(temp, MAXPATHLEN);
231 * Synchronize pool configuration to disk. This must be called with the
232 * namespace lock held. Synchronizing the pool cache is typically done after
233 * the configuration has been synced to the MOS. This exposes a window where
234 * the MOS config will have been updated but the cache file has not. If
235 * the system were to crash at that instant then the cached config may not
236 * contain the correct information to open the pool and an explicit import
240 spa_write_cachefile(spa_t *target, boolean_t removing, boolean_t postsysevent)
242 spa_config_dirent_t *dp, *tdp;
245 boolean_t ccw_failure;
248 ASSERT(MUTEX_HELD(&spa_namespace_lock));
250 if (!(spa_mode_global & SPA_MODE_WRITE))
254 * Iterate over all cachefiles for the pool, past or present. When the
255 * cachefile is changed, the new one is pushed onto this list, allowing
256 * us to update previous cachefiles that no longer contain this pool.
258 ccw_failure = B_FALSE;
259 for (dp = list_head(&target->spa_config_list); dp != NULL;
260 dp = list_next(&target->spa_config_list, dp)) {
262 if (dp->scd_path == NULL)
266 * Iterate over all pools, adding any matching pools to 'nvl'.
269 while ((spa = spa_next(spa)) != NULL) {
271 * Skip over our own pool if we're about to remove
272 * ourselves from the spa namespace or any pool that
273 * is readonly. Since we cannot guarantee that a
274 * readonly pool would successfully import upon reboot,
275 * we don't allow them to be written to the cache file.
277 if ((spa == target && removing) ||
281 mutex_enter(&spa->spa_props_lock);
282 tdp = list_head(&spa->spa_config_list);
283 if (spa->spa_config == NULL ||
285 tdp->scd_path == NULL ||
286 strcmp(tdp->scd_path, dp->scd_path) != 0) {
287 mutex_exit(&spa->spa_props_lock);
292 nvl = fnvlist_alloc();
294 if (spa->spa_import_flags & ZFS_IMPORT_TEMP_NAME)
295 pool_name = fnvlist_lookup_string(
296 spa->spa_config, ZPOOL_CONFIG_POOL_NAME);
298 pool_name = spa_name(spa);
300 fnvlist_add_nvlist(nvl, pool_name, spa->spa_config);
301 mutex_exit(&spa->spa_props_lock);
304 error = spa_config_write(dp, nvl);
306 ccw_failure = B_TRUE;
312 * Keep trying so that configuration data is
313 * written if/when any temporary filesystem
314 * resource issues are resolved.
316 if (target->spa_ccw_fail_time == 0) {
317 (void) zfs_ereport_post(
318 FM_EREPORT_ZFS_CONFIG_CACHE_WRITE,
319 target, NULL, NULL, NULL, 0, 0);
321 target->spa_ccw_fail_time = gethrtime();
322 spa_async_request(target, SPA_ASYNC_CONFIG_UPDATE);
325 * Do not rate limit future attempts to update
328 target->spa_ccw_fail_time = 0;
332 * Remove any config entries older than the current one.
334 dp = list_head(&target->spa_config_list);
335 while ((tdp = list_next(&target->spa_config_list, dp)) != NULL) {
336 list_remove(&target->spa_config_list, tdp);
337 if (tdp->scd_path != NULL)
338 spa_strfree(tdp->scd_path);
339 kmem_free(tdp, sizeof (spa_config_dirent_t));
342 spa_config_generation++;
345 spa_event_notify(target, NULL, NULL, ESC_ZFS_CONFIG_SYNC);
349 * Sigh. Inside a local zone, we don't have access to /etc/zfs/zpool.cache,
350 * and we don't want to allow the local zone to see all the pools anyway.
351 * So we have to invent the ZFS_IOC_CONFIG ioctl to grab the configuration
352 * information for all pool visible within the zone.
355 spa_all_configs(uint64_t *generation)
360 if (*generation == spa_config_generation)
363 pools = fnvlist_alloc();
365 mutex_enter(&spa_namespace_lock);
366 while ((spa = spa_next(spa)) != NULL) {
367 if (INGLOBALZONE(curproc) ||
368 zone_dataset_visible(spa_name(spa), NULL)) {
369 mutex_enter(&spa->spa_props_lock);
370 fnvlist_add_nvlist(pools, spa_name(spa),
372 mutex_exit(&spa->spa_props_lock);
375 *generation = spa_config_generation;
376 mutex_exit(&spa_namespace_lock);
382 spa_config_set(spa_t *spa, nvlist_t *config)
384 mutex_enter(&spa->spa_props_lock);
385 if (spa->spa_config != NULL && spa->spa_config != config)
386 nvlist_free(spa->spa_config);
387 spa->spa_config = config;
388 mutex_exit(&spa->spa_props_lock);
392 * Generate the pool's configuration based on the current in-core state.
394 * We infer whether to generate a complete config or just one top-level config
395 * based on whether vd is the root vdev.
398 spa_config_generate(spa_t *spa, vdev_t *vd, uint64_t txg, int getstats)
400 nvlist_t *config, *nvroot;
401 vdev_t *rvd = spa->spa_root_vdev;
402 unsigned long hostid = 0;
403 boolean_t locked = B_FALSE;
410 spa_config_enter(spa, SCL_CONFIG | SCL_STATE, FTAG, RW_READER);
413 ASSERT(spa_config_held(spa, SCL_CONFIG | SCL_STATE, RW_READER) ==
414 (SCL_CONFIG | SCL_STATE));
417 * If txg is -1, report the current value of spa->spa_config_txg.
420 txg = spa->spa_config_txg;
423 * Originally, users had to handle spa namespace collisions by either
424 * exporting the already imported pool or by specifying a new name for
425 * the pool with a conflicting name. In the case of root pools from
426 * virtual guests, neither approach to collision resolution is
427 * reasonable. This is addressed by extending the new name syntax with
428 * an option to specify that the new name is temporary. When specified,
429 * ZFS_IMPORT_TEMP_NAME will be set in spa->spa_import_flags to tell us
430 * to use the previous name, which we do below.
432 if (spa->spa_import_flags & ZFS_IMPORT_TEMP_NAME) {
433 VERIFY0(nvlist_lookup_string(spa->spa_config,
434 ZPOOL_CONFIG_POOL_NAME, &pool_name));
436 pool_name = spa_name(spa);
438 config = fnvlist_alloc();
440 fnvlist_add_uint64(config, ZPOOL_CONFIG_VERSION, spa_version(spa));
441 fnvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME, pool_name);
442 fnvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE, spa_state(spa));
443 fnvlist_add_uint64(config, ZPOOL_CONFIG_POOL_TXG, txg);
444 fnvlist_add_uint64(config, ZPOOL_CONFIG_POOL_GUID, spa_guid(spa));
445 fnvlist_add_uint64(config, ZPOOL_CONFIG_ERRATA, spa->spa_errata);
446 if (spa->spa_comment != NULL)
447 fnvlist_add_string(config, ZPOOL_CONFIG_COMMENT,
450 hostid = spa_get_hostid(spa);
452 fnvlist_add_uint64(config, ZPOOL_CONFIG_HOSTID, hostid);
453 fnvlist_add_string(config, ZPOOL_CONFIG_HOSTNAME, utsname()->nodename);
455 int config_gen_flags = 0;
457 fnvlist_add_uint64(config, ZPOOL_CONFIG_TOP_GUID,
458 vd->vdev_top->vdev_guid);
459 fnvlist_add_uint64(config, ZPOOL_CONFIG_GUID,
461 if (vd->vdev_isspare)
462 fnvlist_add_uint64(config,
463 ZPOOL_CONFIG_IS_SPARE, 1ULL);
465 fnvlist_add_uint64(config,
466 ZPOOL_CONFIG_IS_LOG, 1ULL);
467 vd = vd->vdev_top; /* label contains top config */
470 * Only add the (potentially large) split information
471 * in the mos config, and not in the vdev labels
473 if (spa->spa_config_splitting != NULL)
474 fnvlist_add_nvlist(config, ZPOOL_CONFIG_SPLIT,
475 spa->spa_config_splitting);
477 fnvlist_add_boolean(config, ZPOOL_CONFIG_HAS_PER_VDEV_ZAPS);
479 config_gen_flags |= VDEV_CONFIG_MOS;
483 * Add the top-level config. We even add this on pools which
484 * don't support holes in the namespace.
486 vdev_top_config_generate(spa, config);
489 * If we're splitting, record the original pool's guid.
491 if (spa->spa_config_splitting != NULL &&
492 nvlist_lookup_uint64(spa->spa_config_splitting,
493 ZPOOL_CONFIG_SPLIT_GUID, &split_guid) == 0) {
494 fnvlist_add_uint64(config, ZPOOL_CONFIG_SPLIT_GUID, split_guid);
497 nvroot = vdev_config_generate(spa, vd, getstats, config_gen_flags);
498 fnvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, nvroot);
502 * Store what's necessary for reading the MOS in the label.
504 fnvlist_add_nvlist(config, ZPOOL_CONFIG_FEATURES_FOR_READ,
505 spa->spa_label_features);
507 if (getstats && spa_load_state(spa) == SPA_LOAD_NONE) {
508 ddt_histogram_t *ddh;
512 ddh = kmem_zalloc(sizeof (ddt_histogram_t), KM_SLEEP);
513 ddt_get_dedup_histogram(spa, ddh);
514 fnvlist_add_uint64_array(config,
515 ZPOOL_CONFIG_DDT_HISTOGRAM,
516 (uint64_t *)ddh, sizeof (*ddh) / sizeof (uint64_t));
517 kmem_free(ddh, sizeof (ddt_histogram_t));
519 ddo = kmem_zalloc(sizeof (ddt_object_t), KM_SLEEP);
520 ddt_get_dedup_object_stats(spa, ddo);
521 fnvlist_add_uint64_array(config,
522 ZPOOL_CONFIG_DDT_OBJ_STATS,
523 (uint64_t *)ddo, sizeof (*ddo) / sizeof (uint64_t));
524 kmem_free(ddo, sizeof (ddt_object_t));
526 dds = kmem_zalloc(sizeof (ddt_stat_t), KM_SLEEP);
527 ddt_get_dedup_stats(spa, dds);
528 fnvlist_add_uint64_array(config,
529 ZPOOL_CONFIG_DDT_STATS,
530 (uint64_t *)dds, sizeof (*dds) / sizeof (uint64_t));
531 kmem_free(dds, sizeof (ddt_stat_t));
535 spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG);
541 * Update all disk labels, generate a fresh config based on the current
542 * in-core state, and sync the global config cache (do not sync the config
543 * cache if this is a booting rootpool).
546 spa_config_update(spa_t *spa, int what)
548 vdev_t *rvd = spa->spa_root_vdev;
552 ASSERT(MUTEX_HELD(&spa_namespace_lock));
554 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
555 txg = spa_last_synced_txg(spa) + 1;
556 if (what == SPA_CONFIG_UPDATE_POOL) {
557 vdev_config_dirty(rvd);
560 * If we have top-level vdevs that were added but have
561 * not yet been prepared for allocation, do that now.
562 * (It's safe now because the config cache is up to date,
563 * so it will be able to translate the new DVAs.)
564 * See comments in spa_vdev_add() for full details.
566 for (c = 0; c < rvd->vdev_children; c++) {
567 vdev_t *tvd = rvd->vdev_child[c];
570 * Explicitly skip vdevs that are indirect or
571 * log vdevs that are being removed. The reason
572 * is that both of those can have vdev_ms_array
573 * set to 0 and we wouldn't want to change their
574 * metaslab size nor call vdev_expand() on them.
576 if (!vdev_is_concrete(tvd) ||
577 (tvd->vdev_islog && tvd->vdev_removing))
580 if (tvd->vdev_ms_array == 0) {
581 vdev_ashift_optimize(tvd);
582 vdev_metaslab_set_size(tvd);
584 vdev_expand(tvd, txg);
587 spa_config_exit(spa, SCL_ALL, FTAG);
590 * Wait for the mosconfig to be regenerated and synced.
592 txg_wait_synced(spa->spa_dsl_pool, txg);
595 * Update the global config cache to reflect the new mosconfig.
597 if (!spa->spa_is_root) {
598 spa_write_cachefile(spa, B_FALSE,
599 what != SPA_CONFIG_UPDATE_POOL);
602 if (what == SPA_CONFIG_UPDATE_POOL)
603 spa_config_update(spa, SPA_CONFIG_UPDATE_VDEVS);
606 EXPORT_SYMBOL(spa_config_load);
607 EXPORT_SYMBOL(spa_all_configs);
608 EXPORT_SYMBOL(spa_config_set);
609 EXPORT_SYMBOL(spa_config_generate);
610 EXPORT_SYMBOL(spa_config_update);
614 /* string sysctls require a char array on FreeBSD */
615 ZFS_MODULE_PARAM(zfs_spa, spa_, config_path, STRING, ZMOD_RD,
616 "SPA config file (/etc/zfs/zpool.cache)");
619 ZFS_MODULE_PARAM(zfs, zfs_, autoimport_disable, INT, ZMOD_RW,
620 "Disable pool import at module load");