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.
30 #include <sys/fm/fs/zfs.h>
31 #include <sys/spa_impl.h>
32 #include <sys/nvpair.h>
34 #include <sys/fs/zfs.h>
35 #include <sys/vdev_impl.h>
36 #include <sys/zfs_ioctl.h>
37 #include <sys/systeminfo.h>
38 #include <sys/sunddi.h>
39 #include <sys/zfeature.h>
46 * Pool configuration repository.
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.
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_write_cachefile(), which
59 * walks through all the active pools and writes the configuration to disk.
62 static uint64_t spa_config_generation = 1;
65 * This can be overridden in userland to preserve an alternate namespace for
66 * userland pools when doing testing.
68 char *spa_config_path = ZPOOL_CACHE;
69 int zfs_autoimport_disable = 1;
72 * Called when the module is first loaded, this routine loads the configuration
73 * file into the SPA namespace. It does not actually open or load the pools; it
74 * only populates the namespace.
80 nvlist_t *nvlist, *child;
87 if (zfs_autoimport_disable)
92 * Open the configuration file.
94 pathname = kmem_alloc(MAXPATHLEN, KM_SLEEP);
96 (void) snprintf(pathname, MAXPATHLEN, "%s%s",
97 (rootdir != NULL) ? "./" : "", spa_config_path);
99 file = kobj_open_file(pathname);
101 kmem_free(pathname, MAXPATHLEN);
103 if (file == (struct _buf *)-1)
106 if (kobj_get_filesize(file, &fsize) != 0)
109 buf = kmem_alloc(fsize, KM_SLEEP);
112 * Read the nvlist from the file.
114 if (kobj_read_file(file, buf, fsize, 0) < 0)
120 if (nvlist_unpack(buf, fsize, &nvlist, KM_SLEEP) != 0)
124 * Iterate over all elements in the nvlist, creating a new spa_t for
125 * each one with the specified configuration.
127 mutex_enter(&spa_namespace_lock);
129 while ((nvpair = nvlist_next_nvpair(nvlist, nvpair)) != NULL) {
130 if (nvpair_type(nvpair) != DATA_TYPE_NVLIST)
133 child = fnvpair_value_nvlist(nvpair);
135 if (spa_lookup(nvpair_name(nvpair)) != NULL)
137 (void) spa_add(nvpair_name(nvpair), child, NULL);
139 mutex_exit(&spa_namespace_lock);
145 kmem_free(buf, fsize);
147 kobj_close_file(file);
151 spa_config_remove(spa_config_dirent_t *dp)
153 #if defined(__linux__) && defined(_KERNEL)
154 int error, flags = FWRITE | FTRUNC;
155 uio_seg_t seg = UIO_SYSSPACE;
158 error = vn_open(dp->scd_path, seg, flags, 0644, &vp, 0, 0);
160 (void) VOP_FSYNC(vp, FSYNC, kcred, NULL);
161 (void) VOP_CLOSE(vp, 0, 1, 0, kcred, NULL);
166 return (vn_remove(dp->scd_path, UIO_SYSSPACE, RMFILE));
171 spa_config_write(spa_config_dirent_t *dp, nvlist_t *nvl)
176 int oflags = FWRITE | FTRUNC | FCREAT | FOFFMAX;
181 * If the nvlist is empty (NULL), then remove the old cachefile.
184 err = spa_config_remove(dp);
192 * Pack the configuration into a buffer.
194 buf = fnvlist_pack(nvl, &buflen);
195 temp = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
197 #if defined(__linux__) && defined(_KERNEL)
199 * Write the configuration to disk. Due to the complexity involved
200 * in performing a rename and remove from within the kernel the file
201 * is instead truncated and overwritten in place. This way we always
202 * have a consistent view of the data or a zero length file.
204 err = vn_open(dp->scd_path, UIO_SYSSPACE, oflags, 0644, &vp, 0, 0);
206 err = vn_rdwr(UIO_WRITE, vp, buf, buflen, 0,
207 UIO_SYSSPACE, 0, RLIM64_INFINITY, kcred, NULL);
209 err = VOP_FSYNC(vp, FSYNC, kcred, NULL);
211 (void) VOP_CLOSE(vp, oflags, 1, 0, kcred, NULL);
213 (void) spa_config_remove(dp);
217 * Write the configuration to disk. We need to do the traditional
218 * 'write to temporary file, sync, move over original' to make sure we
219 * always have a consistent view of the data.
221 (void) snprintf(temp, MAXPATHLEN, "%s.tmp", dp->scd_path);
223 err = vn_open(temp, UIO_SYSSPACE, oflags, 0644, &vp, CRCREAT, 0);
225 err = vn_rdwr(UIO_WRITE, vp, buf, buflen, 0, UIO_SYSSPACE,
226 0, RLIM64_INFINITY, kcred, NULL);
228 err = VOP_FSYNC(vp, FSYNC, kcred, NULL);
230 err = vn_rename(temp, dp->scd_path, UIO_SYSSPACE);
231 (void) VOP_CLOSE(vp, oflags, 1, 0, kcred, NULL);
234 (void) vn_remove(temp, UIO_SYSSPACE, RMFILE);
237 fnvlist_pack_free(buf, buflen);
238 kmem_free(temp, MAXPATHLEN);
243 * Synchronize pool configuration to disk. This must be called with the
244 * namespace lock held. Synchronizing the pool cache is typically done after
245 * the configuration has been synced to the MOS. This exposes a window where
246 * the MOS config will have been updated but the cache file has not. If
247 * the system were to crash at that instant then the cached config may not
248 * contain the correct information to open the pool and an explicit import
252 spa_write_cachefile(spa_t *target, boolean_t removing, boolean_t postsysevent)
254 spa_config_dirent_t *dp, *tdp;
257 boolean_t ccw_failure;
260 ASSERT(MUTEX_HELD(&spa_namespace_lock));
262 if (rootdir == NULL || !(spa_mode_global & FWRITE))
266 * Iterate over all cachefiles for the pool, past or present. When the
267 * cachefile is changed, the new one is pushed onto this list, allowing
268 * us to update previous cachefiles that no longer contain this pool.
270 ccw_failure = B_FALSE;
271 for (dp = list_head(&target->spa_config_list); dp != NULL;
272 dp = list_next(&target->spa_config_list, dp)) {
274 if (dp->scd_path == NULL)
278 * Iterate over all pools, adding any matching pools to 'nvl'.
281 while ((spa = spa_next(spa)) != NULL) {
283 * Skip over our own pool if we're about to remove
284 * ourselves from the spa namespace or any pool that
285 * is readonly. Since we cannot guarantee that a
286 * readonly pool would successfully import upon reboot,
287 * we don't allow them to be written to the cache file.
289 if ((spa == target && removing) ||
293 mutex_enter(&spa->spa_props_lock);
294 tdp = list_head(&spa->spa_config_list);
295 if (spa->spa_config == NULL ||
297 tdp->scd_path == NULL ||
298 strcmp(tdp->scd_path, dp->scd_path) != 0) {
299 mutex_exit(&spa->spa_props_lock);
304 nvl = fnvlist_alloc();
306 if (spa->spa_import_flags & ZFS_IMPORT_TEMP_NAME)
307 pool_name = fnvlist_lookup_string(
308 spa->spa_config, ZPOOL_CONFIG_POOL_NAME);
310 pool_name = spa_name(spa);
312 fnvlist_add_nvlist(nvl, pool_name, spa->spa_config);
313 mutex_exit(&spa->spa_props_lock);
316 error = spa_config_write(dp, nvl);
318 ccw_failure = B_TRUE;
324 * Keep trying so that configuration data is
325 * written if/when any temporary filesystem
326 * resource issues are resolved.
328 if (target->spa_ccw_fail_time == 0) {
329 zfs_ereport_post(FM_EREPORT_ZFS_CONFIG_CACHE_WRITE,
330 target, NULL, NULL, NULL, 0, 0);
332 target->spa_ccw_fail_time = gethrtime();
333 spa_async_request(target, SPA_ASYNC_CONFIG_UPDATE);
336 * Do not rate limit future attempts to update
339 target->spa_ccw_fail_time = 0;
343 * Remove any config entries older than the current one.
345 dp = list_head(&target->spa_config_list);
346 while ((tdp = list_next(&target->spa_config_list, dp)) != NULL) {
347 list_remove(&target->spa_config_list, tdp);
348 if (tdp->scd_path != NULL)
349 spa_strfree(tdp->scd_path);
350 kmem_free(tdp, sizeof (spa_config_dirent_t));
353 spa_config_generation++;
356 spa_event_notify(target, NULL, NULL, ESC_ZFS_CONFIG_SYNC);
360 * Sigh. Inside a local zone, we don't have access to /etc/zfs/zpool.cache,
361 * and we don't want to allow the local zone to see all the pools anyway.
362 * So we have to invent the ZFS_IOC_CONFIG ioctl to grab the configuration
363 * information for all pool visible within the zone.
366 spa_all_configs(uint64_t *generation)
371 if (*generation == spa_config_generation)
374 pools = fnvlist_alloc();
376 mutex_enter(&spa_namespace_lock);
377 while ((spa = spa_next(spa)) != NULL) {
378 if (INGLOBALZONE(curproc) ||
379 zone_dataset_visible(spa_name(spa), NULL)) {
380 mutex_enter(&spa->spa_props_lock);
381 fnvlist_add_nvlist(pools, spa_name(spa),
383 mutex_exit(&spa->spa_props_lock);
386 *generation = spa_config_generation;
387 mutex_exit(&spa_namespace_lock);
393 spa_config_set(spa_t *spa, nvlist_t *config)
395 mutex_enter(&spa->spa_props_lock);
396 if (spa->spa_config != NULL && spa->spa_config != config)
397 nvlist_free(spa->spa_config);
398 spa->spa_config = config;
399 mutex_exit(&spa->spa_props_lock);
403 * Generate the pool's configuration based on the current in-core state.
405 * We infer whether to generate a complete config or just one top-level config
406 * based on whether vd is the root vdev.
409 spa_config_generate(spa_t *spa, vdev_t *vd, uint64_t txg, int getstats)
411 nvlist_t *config, *nvroot;
412 vdev_t *rvd = spa->spa_root_vdev;
413 unsigned long hostid = 0;
414 boolean_t locked = B_FALSE;
421 spa_config_enter(spa, SCL_CONFIG | SCL_STATE, FTAG, RW_READER);
424 ASSERT(spa_config_held(spa, SCL_CONFIG | SCL_STATE, RW_READER) ==
425 (SCL_CONFIG | SCL_STATE));
428 * If txg is -1, report the current value of spa->spa_config_txg.
431 txg = spa->spa_config_txg;
434 * Originally, users had to handle spa namespace collisions by either
435 * exporting the already imported pool or by specifying a new name for
436 * the pool with a conflicting name. In the case of root pools from
437 * virtual guests, neither approach to collision resolution is
438 * reasonable. This is addressed by extending the new name syntax with
439 * an option to specify that the new name is temporary. When specified,
440 * ZFS_IMPORT_TEMP_NAME will be set in spa->spa_import_flags to tell us
441 * to use the previous name, which we do below.
443 if (spa->spa_import_flags & ZFS_IMPORT_TEMP_NAME) {
444 VERIFY0(nvlist_lookup_string(spa->spa_config,
445 ZPOOL_CONFIG_POOL_NAME, &pool_name));
447 pool_name = spa_name(spa);
449 config = fnvlist_alloc();
451 fnvlist_add_uint64(config, ZPOOL_CONFIG_VERSION, spa_version(spa));
452 fnvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME, pool_name);
453 fnvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE, spa_state(spa));
454 fnvlist_add_uint64(config, ZPOOL_CONFIG_POOL_TXG, txg);
455 fnvlist_add_uint64(config, ZPOOL_CONFIG_POOL_GUID, spa_guid(spa));
456 fnvlist_add_uint64(config, ZPOOL_CONFIG_ERRATA, spa->spa_errata);
457 if (spa->spa_comment != NULL)
458 fnvlist_add_string(config, ZPOOL_CONFIG_COMMENT,
461 hostid = spa_get_hostid();
463 fnvlist_add_uint64(config, ZPOOL_CONFIG_HOSTID, hostid);
464 fnvlist_add_string(config, ZPOOL_CONFIG_HOSTNAME, utsname()->nodename);
466 int config_gen_flags = 0;
468 fnvlist_add_uint64(config, ZPOOL_CONFIG_TOP_GUID,
469 vd->vdev_top->vdev_guid);
470 fnvlist_add_uint64(config, ZPOOL_CONFIG_GUID,
472 if (vd->vdev_isspare)
473 fnvlist_add_uint64(config,
474 ZPOOL_CONFIG_IS_SPARE, 1ULL);
476 fnvlist_add_uint64(config,
477 ZPOOL_CONFIG_IS_LOG, 1ULL);
478 vd = vd->vdev_top; /* label contains top config */
481 * Only add the (potentially large) split information
482 * in the mos config, and not in the vdev labels
484 if (spa->spa_config_splitting != NULL)
485 fnvlist_add_nvlist(config, ZPOOL_CONFIG_SPLIT,
486 spa->spa_config_splitting);
488 fnvlist_add_boolean(config, ZPOOL_CONFIG_HAS_PER_VDEV_ZAPS);
490 config_gen_flags |= VDEV_CONFIG_MOS;
494 * Add the top-level config. We even add this on pools which
495 * don't support holes in the namespace.
497 vdev_top_config_generate(spa, config);
500 * If we're splitting, record the original pool's guid.
502 if (spa->spa_config_splitting != NULL &&
503 nvlist_lookup_uint64(spa->spa_config_splitting,
504 ZPOOL_CONFIG_SPLIT_GUID, &split_guid) == 0) {
505 fnvlist_add_uint64(config, ZPOOL_CONFIG_SPLIT_GUID, split_guid);
508 nvroot = vdev_config_generate(spa, vd, getstats, config_gen_flags);
509 fnvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, nvroot);
513 * Store what's necessary for reading the MOS in the label.
515 fnvlist_add_nvlist(config, ZPOOL_CONFIG_FEATURES_FOR_READ,
516 spa->spa_label_features);
518 if (getstats && spa_load_state(spa) == SPA_LOAD_NONE) {
519 ddt_histogram_t *ddh;
523 ddh = kmem_zalloc(sizeof (ddt_histogram_t), KM_SLEEP);
524 ddt_get_dedup_histogram(spa, ddh);
525 fnvlist_add_uint64_array(config,
526 ZPOOL_CONFIG_DDT_HISTOGRAM,
527 (uint64_t *)ddh, sizeof (*ddh) / sizeof (uint64_t));
528 kmem_free(ddh, sizeof (ddt_histogram_t));
530 ddo = kmem_zalloc(sizeof (ddt_object_t), KM_SLEEP);
531 ddt_get_dedup_object_stats(spa, ddo);
532 fnvlist_add_uint64_array(config,
533 ZPOOL_CONFIG_DDT_OBJ_STATS,
534 (uint64_t *)ddo, sizeof (*ddo) / sizeof (uint64_t));
535 kmem_free(ddo, sizeof (ddt_object_t));
537 dds = kmem_zalloc(sizeof (ddt_stat_t), KM_SLEEP);
538 ddt_get_dedup_stats(spa, dds);
539 fnvlist_add_uint64_array(config,
540 ZPOOL_CONFIG_DDT_STATS,
541 (uint64_t *)dds, sizeof (*dds) / sizeof (uint64_t));
542 kmem_free(dds, sizeof (ddt_stat_t));
546 spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG);
552 * Update all disk labels, generate a fresh config based on the current
553 * in-core state, and sync the global config cache (do not sync the config
554 * cache if this is a booting rootpool).
557 spa_config_update(spa_t *spa, int what)
559 vdev_t *rvd = spa->spa_root_vdev;
563 ASSERT(MUTEX_HELD(&spa_namespace_lock));
565 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
566 txg = spa_last_synced_txg(spa) + 1;
567 if (what == SPA_CONFIG_UPDATE_POOL) {
568 vdev_config_dirty(rvd);
571 * If we have top-level vdevs that were added but have
572 * not yet been prepared for allocation, do that now.
573 * (It's safe now because the config cache is up to date,
574 * so it will be able to translate the new DVAs.)
575 * See comments in spa_vdev_add() for full details.
577 for (c = 0; c < rvd->vdev_children; c++) {
578 vdev_t *tvd = rvd->vdev_child[c];
581 * Explicitly skip vdevs that are indirect or
582 * log vdevs that are being removed. The reason
583 * is that both of those can have vdev_ms_array
584 * set to 0 and we wouldn't want to change their
585 * metaslab size nor call vdev_expand() on them.
587 if (!vdev_is_concrete(tvd) ||
588 (tvd->vdev_islog && tvd->vdev_removing))
591 if (tvd->vdev_ms_array == 0)
592 vdev_metaslab_set_size(tvd);
593 vdev_expand(tvd, txg);
596 spa_config_exit(spa, SCL_ALL, FTAG);
599 * Wait for the mosconfig to be regenerated and synced.
601 txg_wait_synced(spa->spa_dsl_pool, txg);
604 * Update the global config cache to reflect the new mosconfig.
606 if (!spa->spa_is_root) {
607 spa_write_cachefile(spa, B_FALSE,
608 what != SPA_CONFIG_UPDATE_POOL);
611 if (what == SPA_CONFIG_UPDATE_POOL)
612 spa_config_update(spa, SPA_CONFIG_UPDATE_VDEVS);
616 EXPORT_SYMBOL(spa_config_load);
617 EXPORT_SYMBOL(spa_all_configs);
618 EXPORT_SYMBOL(spa_config_set);
619 EXPORT_SYMBOL(spa_config_generate);
620 EXPORT_SYMBOL(spa_config_update);
622 module_param(spa_config_path, charp, 0444);
623 MODULE_PARM_DESC(spa_config_path, "SPA config file (/etc/zfs/zpool.cache)");
625 module_param(zfs_autoimport_disable, int, 0644);
626 MODULE_PARM_DESC(zfs_autoimport_disable, "Disable pool import at module load");