spa_config.c revision 219089
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 */ 25 26#include <sys/zfs_context.h> 27#include <sys/spa.h> 28#include <sys/spa_impl.h> 29#include <sys/nvpair.h> 30#include <sys/uio.h> 31#include <sys/fs/zfs.h> 32#include <sys/vdev_impl.h> 33#include <sys/zfs_ioctl.h> 34#include <sys/utsname.h> 35#include <sys/sunddi.h> 36#ifdef _KERNEL 37#include <sys/kobj.h> 38#include <sys/zone.h> 39#endif 40 41/* 42 * Pool configuration repository. 43 * 44 * Pool configuration is stored as a packed nvlist on the filesystem. By 45 * default, all pools are stored in /etc/zfs/zpool.cache and loaded on boot 46 * (when the ZFS module is loaded). Pools can also have the 'cachefile' 47 * property set that allows them to be stored in an alternate location until 48 * the control of external software. 49 * 50 * For each cache file, we have a single nvlist which holds all the 51 * configuration information. When the module loads, we read this information 52 * from /etc/zfs/zpool.cache and populate the SPA namespace. This namespace is 53 * maintained independently in spa.c. Whenever the namespace is modified, or 54 * the configuration of a pool is changed, we call spa_config_sync(), which 55 * walks through all the active pools and writes the configuration to disk. 56 */ 57 58static uint64_t spa_config_generation = 1; 59 60/* 61 * This can be overridden in userland to preserve an alternate namespace for 62 * userland pools when doing testing. 63 */ 64const char *spa_config_path = ZPOOL_CACHE; 65 66/* 67 * Called when the module is first loaded, this routine loads the configuration 68 * file into the SPA namespace. It does not actually open or load the pools; it 69 * only populates the namespace. 70 */ 71void 72spa_config_load(void) 73{ 74 void *buf = NULL; 75 nvlist_t *nvlist, *child; 76 nvpair_t *nvpair; 77 char *pathname; 78 struct _buf *file; 79 uint64_t fsize; 80 81 /* 82 * Open the configuration file. 83 */ 84 pathname = kmem_alloc(MAXPATHLEN, KM_SLEEP); 85 86 (void) snprintf(pathname, MAXPATHLEN, "%s", spa_config_path); 87 88 file = kobj_open_file(pathname); 89 90 kmem_free(pathname, MAXPATHLEN); 91 92 if (file == (struct _buf *)-1) 93 return; 94 95 if (kobj_get_filesize(file, &fsize) != 0) 96 goto out; 97 98 buf = kmem_alloc(fsize, KM_SLEEP); 99 100 /* 101 * Read the nvlist from the file. 102 */ 103 if (kobj_read_file(file, buf, fsize, 0) < 0) 104 goto out; 105 106 /* 107 * Unpack the nvlist. 108 */ 109 if (nvlist_unpack(buf, fsize, &nvlist, KM_SLEEP) != 0) 110 goto out; 111 112 /* 113 * Iterate over all elements in the nvlist, creating a new spa_t for 114 * each one with the specified configuration. 115 */ 116 mutex_enter(&spa_namespace_lock); 117 nvpair = NULL; 118 while ((nvpair = nvlist_next_nvpair(nvlist, nvpair)) != NULL) { 119 if (nvpair_type(nvpair) != DATA_TYPE_NVLIST) 120 continue; 121 122 VERIFY(nvpair_value_nvlist(nvpair, &child) == 0); 123 124 if (spa_lookup(nvpair_name(nvpair)) != NULL) 125 continue; 126 (void) spa_add(nvpair_name(nvpair), child, NULL); 127 } 128 mutex_exit(&spa_namespace_lock); 129 130 nvlist_free(nvlist); 131 132out: 133 if (buf != NULL) 134 kmem_free(buf, fsize); 135 136 kobj_close_file(file); 137} 138 139static void 140spa_config_write(spa_config_dirent_t *dp, nvlist_t *nvl) 141{ 142 size_t buflen; 143 char *buf; 144 vnode_t *vp; 145 int oflags = FWRITE | FTRUNC | FCREAT | FOFFMAX; 146 char *temp; 147 148 /* 149 * If the nvlist is empty (NULL), then remove the old cachefile. 150 */ 151 if (nvl == NULL) { 152 (void) vn_remove(dp->scd_path, UIO_SYSSPACE, RMFILE); 153 return; 154 } 155 156 /* 157 * Pack the configuration into a buffer. 158 */ 159 VERIFY(nvlist_size(nvl, &buflen, NV_ENCODE_XDR) == 0); 160 161 buf = kmem_alloc(buflen, KM_SLEEP); 162 temp = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 163 164 VERIFY(nvlist_pack(nvl, &buf, &buflen, NV_ENCODE_XDR, 165 KM_SLEEP) == 0); 166 167 /* 168 * Write the configuration to disk. We need to do the traditional 169 * 'write to temporary file, sync, move over original' to make sure we 170 * always have a consistent view of the data. 171 */ 172 (void) snprintf(temp, MAXPATHLEN, "%s.tmp", dp->scd_path); 173 174 if (vn_open(temp, UIO_SYSSPACE, oflags, 0644, &vp, CRCREAT, 0) == 0) { 175 if (vn_rdwr(UIO_WRITE, vp, buf, buflen, 0, UIO_SYSSPACE, 176 0, RLIM64_INFINITY, kcred, NULL) == 0 && 177 VOP_FSYNC(vp, FSYNC, kcred, NULL) == 0) { 178 (void) vn_rename(temp, dp->scd_path, UIO_SYSSPACE); 179 } 180 (void) VOP_CLOSE(vp, oflags, 1, 0, kcred, NULL); 181 } 182 183 (void) vn_remove(temp, UIO_SYSSPACE, RMFILE); 184 185 kmem_free(buf, buflen); 186 kmem_free(temp, MAXPATHLEN); 187} 188 189/* 190 * Synchronize pool configuration to disk. This must be called with the 191 * namespace lock held. 192 */ 193void 194spa_config_sync(spa_t *target, boolean_t removing, boolean_t postsysevent) 195{ 196 spa_config_dirent_t *dp, *tdp; 197 nvlist_t *nvl; 198 199 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 200 201 if (rootdir == NULL || !(spa_mode_global & FWRITE)) 202 return; 203 204 /* 205 * Iterate over all cachefiles for the pool, past or present. When the 206 * cachefile is changed, the new one is pushed onto this list, allowing 207 * us to update previous cachefiles that no longer contain this pool. 208 */ 209 for (dp = list_head(&target->spa_config_list); dp != NULL; 210 dp = list_next(&target->spa_config_list, dp)) { 211 spa_t *spa = NULL; 212 if (dp->scd_path == NULL) 213 continue; 214 215 /* 216 * Iterate over all pools, adding any matching pools to 'nvl'. 217 */ 218 nvl = NULL; 219 while ((spa = spa_next(spa)) != NULL) { 220 if (spa == target && removing) 221 continue; 222 223 mutex_enter(&spa->spa_props_lock); 224 tdp = list_head(&spa->spa_config_list); 225 if (spa->spa_config == NULL || 226 tdp->scd_path == NULL || 227 strcmp(tdp->scd_path, dp->scd_path) != 0) { 228 mutex_exit(&spa->spa_props_lock); 229 continue; 230 } 231 232 if (nvl == NULL) 233 VERIFY(nvlist_alloc(&nvl, NV_UNIQUE_NAME, 234 KM_SLEEP) == 0); 235 236 VERIFY(nvlist_add_nvlist(nvl, spa->spa_name, 237 spa->spa_config) == 0); 238 mutex_exit(&spa->spa_props_lock); 239 } 240 241 spa_config_write(dp, nvl); 242 nvlist_free(nvl); 243 } 244 245 /* 246 * Remove any config entries older than the current one. 247 */ 248 dp = list_head(&target->spa_config_list); 249 while ((tdp = list_next(&target->spa_config_list, dp)) != NULL) { 250 list_remove(&target->spa_config_list, tdp); 251 if (tdp->scd_path != NULL) 252 spa_strfree(tdp->scd_path); 253 kmem_free(tdp, sizeof (spa_config_dirent_t)); 254 } 255 256 spa_config_generation++; 257 258 if (postsysevent) 259 spa_event_notify(target, NULL, ESC_ZFS_CONFIG_SYNC); 260} 261 262/* 263 * Sigh. Inside a local zone, we don't have access to /etc/zfs/zpool.cache, 264 * and we don't want to allow the local zone to see all the pools anyway. 265 * So we have to invent the ZFS_IOC_CONFIG ioctl to grab the configuration 266 * information for all pool visible within the zone. 267 */ 268nvlist_t * 269spa_all_configs(uint64_t *generation) 270{ 271 nvlist_t *pools; 272 spa_t *spa = NULL; 273 274 if (*generation == spa_config_generation) 275 return (NULL); 276 277 VERIFY(nvlist_alloc(&pools, NV_UNIQUE_NAME, KM_SLEEP) == 0); 278 279 mutex_enter(&spa_namespace_lock); 280 while ((spa = spa_next(spa)) != NULL) { 281 if (INGLOBALZONE(curthread) || 282 zone_dataset_visible(spa_name(spa), NULL)) { 283 mutex_enter(&spa->spa_props_lock); 284 VERIFY(nvlist_add_nvlist(pools, spa_name(spa), 285 spa->spa_config) == 0); 286 mutex_exit(&spa->spa_props_lock); 287 } 288 } 289 *generation = spa_config_generation; 290 mutex_exit(&spa_namespace_lock); 291 292 return (pools); 293} 294 295void 296spa_config_set(spa_t *spa, nvlist_t *config) 297{ 298 mutex_enter(&spa->spa_props_lock); 299 if (spa->spa_config != NULL) 300 nvlist_free(spa->spa_config); 301 spa->spa_config = config; 302 mutex_exit(&spa->spa_props_lock); 303} 304 305/* 306 * Generate the pool's configuration based on the current in-core state. 307 * We infer whether to generate a complete config or just one top-level config 308 * based on whether vd is the root vdev. 309 */ 310nvlist_t * 311spa_config_generate(spa_t *spa, vdev_t *vd, uint64_t txg, int getstats) 312{ 313 nvlist_t *config, *nvroot; 314 vdev_t *rvd = spa->spa_root_vdev; 315 unsigned long hostid = 0; 316 boolean_t locked = B_FALSE; 317 uint64_t split_guid; 318 319 if (vd == NULL) { 320 vd = rvd; 321 locked = B_TRUE; 322 spa_config_enter(spa, SCL_CONFIG | SCL_STATE, FTAG, RW_READER); 323 } 324 325 ASSERT(spa_config_held(spa, SCL_CONFIG | SCL_STATE, RW_READER) == 326 (SCL_CONFIG | SCL_STATE)); 327 328 /* 329 * If txg is -1, report the current value of spa->spa_config_txg. 330 */ 331 if (txg == -1ULL) 332 txg = spa->spa_config_txg; 333 334 VERIFY(nvlist_alloc(&config, NV_UNIQUE_NAME, KM_SLEEP) == 0); 335 336 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VERSION, 337 spa_version(spa)) == 0); 338 VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME, 339 spa_name(spa)) == 0); 340 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE, 341 spa_state(spa)) == 0); 342 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_TXG, 343 txg) == 0); 344 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_GUID, 345 spa_guid(spa)) == 0); 346#ifdef _KERNEL 347 hostid = zone_get_hostid(NULL); 348#else /* _KERNEL */ 349 /* 350 * We're emulating the system's hostid in userland, so we can't use 351 * zone_get_hostid(). 352 */ 353 (void) ddi_strtoul(hw_serial, NULL, 10, &hostid); 354#endif /* _KERNEL */ 355 if (hostid != 0) { 356 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_HOSTID, 357 hostid) == 0); 358 } 359 VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_HOSTNAME, 360 utsname.nodename) == 0); 361 362 if (vd != rvd) { 363 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_TOP_GUID, 364 vd->vdev_top->vdev_guid) == 0); 365 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_GUID, 366 vd->vdev_guid) == 0); 367 if (vd->vdev_isspare) 368 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_IS_SPARE, 369 1ULL) == 0); 370 if (vd->vdev_islog) 371 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_IS_LOG, 372 1ULL) == 0); 373 vd = vd->vdev_top; /* label contains top config */ 374 } else { 375 /* 376 * Only add the (potentially large) split information 377 * in the mos config, and not in the vdev labels 378 */ 379 if (spa->spa_config_splitting != NULL) 380 VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_SPLIT, 381 spa->spa_config_splitting) == 0); 382 } 383 384 /* 385 * Add the top-level config. We even add this on pools which 386 * don't support holes in the namespace. 387 */ 388 vdev_top_config_generate(spa, config); 389 390 /* 391 * If we're splitting, record the original pool's guid. 392 */ 393 if (spa->spa_config_splitting != NULL && 394 nvlist_lookup_uint64(spa->spa_config_splitting, 395 ZPOOL_CONFIG_SPLIT_GUID, &split_guid) == 0) { 396 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_SPLIT_GUID, 397 split_guid) == 0); 398 } 399 400 nvroot = vdev_config_generate(spa, vd, getstats, 0); 401 VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, nvroot) == 0); 402 nvlist_free(nvroot); 403 404 if (getstats && spa_load_state(spa) == SPA_LOAD_NONE) { 405 ddt_histogram_t *ddh; 406 ddt_stat_t *dds; 407 ddt_object_t *ddo; 408 409 ddh = kmem_zalloc(sizeof (ddt_histogram_t), KM_SLEEP); 410 ddt_get_dedup_histogram(spa, ddh); 411 VERIFY(nvlist_add_uint64_array(config, 412 ZPOOL_CONFIG_DDT_HISTOGRAM, 413 (uint64_t *)ddh, sizeof (*ddh) / sizeof (uint64_t)) == 0); 414 kmem_free(ddh, sizeof (ddt_histogram_t)); 415 416 ddo = kmem_zalloc(sizeof (ddt_object_t), KM_SLEEP); 417 ddt_get_dedup_object_stats(spa, ddo); 418 VERIFY(nvlist_add_uint64_array(config, 419 ZPOOL_CONFIG_DDT_OBJ_STATS, 420 (uint64_t *)ddo, sizeof (*ddo) / sizeof (uint64_t)) == 0); 421 kmem_free(ddo, sizeof (ddt_object_t)); 422 423 dds = kmem_zalloc(sizeof (ddt_stat_t), KM_SLEEP); 424 ddt_get_dedup_stats(spa, dds); 425 VERIFY(nvlist_add_uint64_array(config, 426 ZPOOL_CONFIG_DDT_STATS, 427 (uint64_t *)dds, sizeof (*dds) / sizeof (uint64_t)) == 0); 428 kmem_free(dds, sizeof (ddt_stat_t)); 429 } 430 431 if (locked) 432 spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG); 433 434 return (config); 435} 436 437/* 438 * Update all disk labels, generate a fresh config based on the current 439 * in-core state, and sync the global config cache (do not sync the config 440 * cache if this is a booting rootpool). 441 */ 442void 443spa_config_update(spa_t *spa, int what) 444{ 445 vdev_t *rvd = spa->spa_root_vdev; 446 uint64_t txg; 447 int c; 448 449 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 450 451 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER); 452 txg = spa_last_synced_txg(spa) + 1; 453 if (what == SPA_CONFIG_UPDATE_POOL) { 454 vdev_config_dirty(rvd); 455 } else { 456 /* 457 * If we have top-level vdevs that were added but have 458 * not yet been prepared for allocation, do that now. 459 * (It's safe now because the config cache is up to date, 460 * so it will be able to translate the new DVAs.) 461 * See comments in spa_vdev_add() for full details. 462 */ 463 for (c = 0; c < rvd->vdev_children; c++) { 464 vdev_t *tvd = rvd->vdev_child[c]; 465 if (tvd->vdev_ms_array == 0) 466 vdev_metaslab_set_size(tvd); 467 vdev_expand(tvd, txg); 468 } 469 } 470 spa_config_exit(spa, SCL_ALL, FTAG); 471 472 /* 473 * Wait for the mosconfig to be regenerated and synced. 474 */ 475 txg_wait_synced(spa->spa_dsl_pool, txg); 476 477 /* 478 * Update the global config cache to reflect the new mosconfig. 479 */ 480 if (!spa->spa_is_root) 481 spa_config_sync(spa, B_FALSE, what != SPA_CONFIG_UPDATE_POOL); 482 483 if (what == SPA_CONFIG_UPDATE_POOL) 484 spa_config_update(spa, SPA_CONFIG_UPDATE_VDEVS); 485} 486