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) 2013 by Delphix. All rights reserved.
28 #include <sys/zfs_context.h>
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/utsname.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_config_sync(), 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 const char *spa_config_path = ZPOOL_CACHE;
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.
79 nvlist_t *nvlist, *child;
86 * Open the configuration file.
88 pathname = kmem_alloc(MAXPATHLEN, KM_SLEEP);
90 (void) snprintf(pathname, MAXPATHLEN, "%s", spa_config_path);
92 file = kobj_open_file(pathname);
94 kmem_free(pathname, MAXPATHLEN);
96 if (file == (struct _buf *)-1)
99 if (kobj_get_filesize(file, &fsize) != 0)
102 buf = kmem_alloc(fsize, KM_SLEEP);
105 * Read the nvlist from the file.
107 if (kobj_read_file(file, buf, fsize, 0) < 0)
113 if (nvlist_unpack(buf, fsize, &nvlist, KM_SLEEP) != 0)
117 * Iterate over all elements in the nvlist, creating a new spa_t for
118 * each one with the specified configuration.
120 mutex_enter(&spa_namespace_lock);
122 while ((nvpair = nvlist_next_nvpair(nvlist, nvpair)) != NULL) {
123 if (nvpair_type(nvpair) != DATA_TYPE_NVLIST)
126 VERIFY(nvpair_value_nvlist(nvpair, &child) == 0);
128 if (spa_lookup(nvpair_name(nvpair)) != NULL)
130 (void) spa_add(nvpair_name(nvpair), child, NULL);
132 mutex_exit(&spa_namespace_lock);
138 kmem_free(buf, fsize);
140 kobj_close_file(file);
144 spa_config_write(spa_config_dirent_t *dp, nvlist_t *nvl)
149 int oflags = FWRITE | FTRUNC | FCREAT | FOFFMAX;
154 * If the nvlist is empty (NULL), then remove the old cachefile.
157 err = vn_remove(dp->scd_path, UIO_SYSSPACE, RMFILE);
162 * Pack the configuration into a buffer.
164 VERIFY(nvlist_size(nvl, &buflen, NV_ENCODE_XDR) == 0);
166 buf = kmem_alloc(buflen, KM_SLEEP);
167 temp = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
169 VERIFY(nvlist_pack(nvl, &buf, &buflen, NV_ENCODE_XDR,
173 * Write the configuration to disk. We need to do the traditional
174 * 'write to temporary file, sync, move over original' to make sure we
175 * always have a consistent view of the data.
177 (void) snprintf(temp, MAXPATHLEN, "%s.tmp", dp->scd_path);
179 err = vn_open(temp, UIO_SYSSPACE, oflags, 0644, &vp, CRCREAT, 0);
181 err = vn_rdwr(UIO_WRITE, vp, buf, buflen, 0, UIO_SYSSPACE,
182 0, RLIM64_INFINITY, kcred, NULL);
184 err = VOP_FSYNC(vp, FSYNC, kcred, NULL);
186 err = vn_rename(temp, dp->scd_path, UIO_SYSSPACE);
187 (void) VOP_CLOSE(vp, oflags, 1, 0, kcred, NULL);
190 (void) vn_remove(temp, UIO_SYSSPACE, RMFILE);
192 kmem_free(buf, buflen);
193 kmem_free(temp, MAXPATHLEN);
198 * Synchronize pool configuration to disk. This must be called with the
199 * namespace lock held. Synchronizing the pool cache is typically done after
200 * the configuration has been synced to the MOS. This exposes a window where
201 * the MOS config will have been updated but the cache file has not. If
202 * the system were to crash at that instant then the cached config may not
203 * contain the correct information to open the pool and an explicity import
207 spa_config_sync(spa_t *target, boolean_t removing, boolean_t postsysevent)
209 spa_config_dirent_t *dp, *tdp;
211 boolean_t ccw_failure;
214 ASSERT(MUTEX_HELD(&spa_namespace_lock));
216 if (rootdir == NULL || !(spa_mode_global & FWRITE))
220 * Iterate over all cachefiles for the pool, past or present. When the
221 * cachefile is changed, the new one is pushed onto this list, allowing
222 * us to update previous cachefiles that no longer contain this pool.
224 ccw_failure = B_FALSE;
225 for (dp = list_head(&target->spa_config_list); dp != NULL;
226 dp = list_next(&target->spa_config_list, dp)) {
228 if (dp->scd_path == NULL)
232 * Iterate over all pools, adding any matching pools to 'nvl'.
235 while ((spa = spa_next(spa)) != NULL) {
237 * Skip over our own pool if we're about to remove
238 * ourselves from the spa namespace or any pool that
239 * is readonly. Since we cannot guarantee that a
240 * readonly pool would successfully import upon reboot,
241 * we don't allow them to be written to the cache file.
243 if ((spa == target && removing) ||
247 mutex_enter(&spa->spa_props_lock);
248 tdp = list_head(&spa->spa_config_list);
249 if (spa->spa_config == NULL ||
250 tdp->scd_path == NULL ||
251 strcmp(tdp->scd_path, dp->scd_path) != 0) {
252 mutex_exit(&spa->spa_props_lock);
257 VERIFY(nvlist_alloc(&nvl, NV_UNIQUE_NAME,
260 VERIFY(nvlist_add_nvlist(nvl, spa->spa_name,
261 spa->spa_config) == 0);
262 mutex_exit(&spa->spa_props_lock);
265 error = spa_config_write(dp, nvl);
267 ccw_failure = B_TRUE;
273 * Keep trying so that configuration data is
274 * written if/when any temporary filesystem
275 * resource issues are resolved.
277 if (target->spa_ccw_fail_time == 0) {
278 zfs_ereport_post(FM_EREPORT_ZFS_CONFIG_CACHE_WRITE,
279 target, NULL, NULL, 0, 0);
281 target->spa_ccw_fail_time = gethrtime();
282 spa_async_request(target, SPA_ASYNC_CONFIG_UPDATE);
285 * Do not rate limit future attempts to update
288 target->spa_ccw_fail_time = 0;
292 * Remove any config entries older than the current one.
294 dp = list_head(&target->spa_config_list);
295 while ((tdp = list_next(&target->spa_config_list, dp)) != NULL) {
296 list_remove(&target->spa_config_list, tdp);
297 if (tdp->scd_path != NULL)
298 spa_strfree(tdp->scd_path);
299 kmem_free(tdp, sizeof (spa_config_dirent_t));
302 spa_config_generation++;
305 spa_event_notify(target, NULL, ESC_ZFS_CONFIG_SYNC);
309 * Sigh. Inside a local zone, we don't have access to /etc/zfs/zpool.cache,
310 * and we don't want to allow the local zone to see all the pools anyway.
311 * So we have to invent the ZFS_IOC_CONFIG ioctl to grab the configuration
312 * information for all pool visible within the zone.
315 spa_all_configs(uint64_t *generation)
320 if (*generation == spa_config_generation)
323 VERIFY(nvlist_alloc(&pools, NV_UNIQUE_NAME, KM_SLEEP) == 0);
325 mutex_enter(&spa_namespace_lock);
326 while ((spa = spa_next(spa)) != NULL) {
327 if (INGLOBALZONE(curthread) ||
328 zone_dataset_visible(spa_name(spa), NULL)) {
329 mutex_enter(&spa->spa_props_lock);
330 VERIFY(nvlist_add_nvlist(pools, spa_name(spa),
331 spa->spa_config) == 0);
332 mutex_exit(&spa->spa_props_lock);
335 *generation = spa_config_generation;
336 mutex_exit(&spa_namespace_lock);
342 spa_config_set(spa_t *spa, nvlist_t *config)
344 mutex_enter(&spa->spa_props_lock);
345 if (spa->spa_config != NULL)
346 nvlist_free(spa->spa_config);
347 spa->spa_config = config;
348 mutex_exit(&spa->spa_props_lock);
352 * Generate the pool's configuration based on the current in-core state.
354 * We infer whether to generate a complete config or just one top-level config
355 * based on whether vd is the root vdev.
358 spa_config_generate(spa_t *spa, vdev_t *vd, uint64_t txg, int getstats)
360 nvlist_t *config, *nvroot;
361 vdev_t *rvd = spa->spa_root_vdev;
362 unsigned long hostid = 0;
363 boolean_t locked = B_FALSE;
369 spa_config_enter(spa, SCL_CONFIG | SCL_STATE, FTAG, RW_READER);
372 ASSERT(spa_config_held(spa, SCL_CONFIG | SCL_STATE, RW_READER) ==
373 (SCL_CONFIG | SCL_STATE));
376 * If txg is -1, report the current value of spa->spa_config_txg.
379 txg = spa->spa_config_txg;
381 VERIFY(nvlist_alloc(&config, NV_UNIQUE_NAME, KM_SLEEP) == 0);
383 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VERSION,
384 spa_version(spa)) == 0);
385 VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME,
386 spa_name(spa)) == 0);
387 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE,
388 spa_state(spa)) == 0);
389 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_TXG,
391 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_GUID,
392 spa_guid(spa)) == 0);
393 VERIFY(spa->spa_comment == NULL || nvlist_add_string(config,
394 ZPOOL_CONFIG_COMMENT, spa->spa_comment) == 0);
398 hostid = zone_get_hostid(NULL);
401 * We're emulating the system's hostid in userland, so we can't use
404 (void) ddi_strtoul(hw_serial, NULL, 10, &hostid);
407 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_HOSTID,
410 VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_HOSTNAME,
411 utsname.nodename) == 0);
414 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_TOP_GUID,
415 vd->vdev_top->vdev_guid) == 0);
416 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_GUID,
417 vd->vdev_guid) == 0);
418 if (vd->vdev_isspare)
419 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_IS_SPARE,
422 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_IS_LOG,
424 vd = vd->vdev_top; /* label contains top config */
427 * Only add the (potentially large) split information
428 * in the mos config, and not in the vdev labels
430 if (spa->spa_config_splitting != NULL)
431 VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_SPLIT,
432 spa->spa_config_splitting) == 0);
436 * Add the top-level config. We even add this on pools which
437 * don't support holes in the namespace.
439 vdev_top_config_generate(spa, config);
442 * If we're splitting, record the original pool's guid.
444 if (spa->spa_config_splitting != NULL &&
445 nvlist_lookup_uint64(spa->spa_config_splitting,
446 ZPOOL_CONFIG_SPLIT_GUID, &split_guid) == 0) {
447 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_SPLIT_GUID,
451 nvroot = vdev_config_generate(spa, vd, getstats, 0);
452 VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, nvroot) == 0);
456 * Store what's necessary for reading the MOS in the label.
458 VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_FEATURES_FOR_READ,
459 spa->spa_label_features) == 0);
461 if (getstats && spa_load_state(spa) == SPA_LOAD_NONE) {
462 ddt_histogram_t *ddh;
466 ddh = kmem_zalloc(sizeof (ddt_histogram_t), KM_SLEEP);
467 ddt_get_dedup_histogram(spa, ddh);
468 VERIFY(nvlist_add_uint64_array(config,
469 ZPOOL_CONFIG_DDT_HISTOGRAM,
470 (uint64_t *)ddh, sizeof (*ddh) / sizeof (uint64_t)) == 0);
471 kmem_free(ddh, sizeof (ddt_histogram_t));
473 ddo = kmem_zalloc(sizeof (ddt_object_t), KM_SLEEP);
474 ddt_get_dedup_object_stats(spa, ddo);
475 VERIFY(nvlist_add_uint64_array(config,
476 ZPOOL_CONFIG_DDT_OBJ_STATS,
477 (uint64_t *)ddo, sizeof (*ddo) / sizeof (uint64_t)) == 0);
478 kmem_free(ddo, sizeof (ddt_object_t));
480 dds = kmem_zalloc(sizeof (ddt_stat_t), KM_SLEEP);
481 ddt_get_dedup_stats(spa, dds);
482 VERIFY(nvlist_add_uint64_array(config,
483 ZPOOL_CONFIG_DDT_STATS,
484 (uint64_t *)dds, sizeof (*dds) / sizeof (uint64_t)) == 0);
485 kmem_free(dds, sizeof (ddt_stat_t));
489 spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG);
495 * Update all disk labels, generate a fresh config based on the current
496 * in-core state, and sync the global config cache (do not sync the config
497 * cache if this is a booting rootpool).
500 spa_config_update(spa_t *spa, int what)
502 vdev_t *rvd = spa->spa_root_vdev;
506 ASSERT(MUTEX_HELD(&spa_namespace_lock));
508 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
509 txg = spa_last_synced_txg(spa) + 1;
510 if (what == SPA_CONFIG_UPDATE_POOL) {
511 vdev_config_dirty(rvd);
514 * If we have top-level vdevs that were added but have
515 * not yet been prepared for allocation, do that now.
516 * (It's safe now because the config cache is up to date,
517 * so it will be able to translate the new DVAs.)
518 * See comments in spa_vdev_add() for full details.
520 for (c = 0; c < rvd->vdev_children; c++) {
521 vdev_t *tvd = rvd->vdev_child[c];
522 if (tvd->vdev_ms_array == 0) {
523 vdev_ashift_optimize(tvd);
524 vdev_metaslab_set_size(tvd);
526 vdev_expand(tvd, txg);
529 spa_config_exit(spa, SCL_ALL, FTAG);
532 * Wait for the mosconfig to be regenerated and synced.
534 txg_wait_synced(spa->spa_dsl_pool, txg);
537 * Update the global config cache to reflect the new mosconfig.
539 if (!spa->spa_is_root)
540 spa_config_sync(spa, B_FALSE, what != SPA_CONFIG_UPDATE_POOL);
542 if (what == SPA_CONFIG_UPDATE_POOL)
543 spa_config_update(spa, SPA_CONFIG_UPDATE_VDEVS);