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 2009 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 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/systeminfo.h> 36 #include <sys/sunddi.h> 37 #ifdef _KERNEL 38 #include <sys/kobj.h> 39 #include <sys/zone.h> 40 #endif 41 42 /* 43 * Pool configuration repository. 44 * 45 * Pool configuration is stored as a packed nvlist on the filesystem. By 46 * default, all pools are stored in /etc/zfs/zpool.cache and loaded on boot 47 * (when the ZFS module is loaded). Pools can also have the 'cachefile' 48 * property set that allows them to be stored in an alternate location until 49 * the control of external software. 50 * 51 * For each cache file, we have a single nvlist which holds all the 52 * configuration information. When the module loads, we read this information 53 * from /etc/zfs/zpool.cache and populate the SPA namespace. This namespace is 54 * maintained independently in spa.c. Whenever the namespace is modified, or 55 * the configuration of a pool is changed, we call spa_config_sync(), which 56 * walks through all the active pools and writes the configuration to disk. 57 */ 58 59 static uint64_t spa_config_generation = 1; 60 61 /* 62 * This can be overridden in userland to preserve an alternate namespace for 63 * userland pools when doing testing. 64 */ 65 const char *spa_config_path = ZPOOL_CACHE; 66 67 /* 68 * Called when the module is first loaded, this routine loads the configuration 69 * file into the SPA namespace. It does not actually open or load the pools; it 70 * only populates the namespace. 71 */ 72 void 73 spa_config_load(void) 74 { 75 void *buf = NULL; 76 nvlist_t *nvlist, *child; 77 nvpair_t *nvpair; 78 spa_t *spa; 79 char *pathname; 80 struct _buf *file; 81 uint64_t fsize; 82 83 /* 84 * Open the configuration file. 85 */ 86 pathname = kmem_alloc(MAXPATHLEN, KM_SLEEP); 87 88 (void) snprintf(pathname, MAXPATHLEN, "%s%s", 89 (rootdir != NULL) ? "./" : "", spa_config_path); 90 91 file = kobj_open_file(pathname); 92 93 kmem_free(pathname, MAXPATHLEN); 94 95 if (file == (struct _buf *)-1) 96 return; 97 98 if (kobj_get_filesize(file, &fsize) != 0) 99 goto out; 100 101 buf = kmem_alloc(fsize, KM_SLEEP); 102 103 /* 104 * Read the nvlist from the file. 105 */ 106 if (kobj_read_file(file, buf, fsize, 0) < 0) 107 goto out; 108 109 /* 110 * Unpack the nvlist. 111 */ 112 if (nvlist_unpack(buf, fsize, &nvlist, KM_SLEEP) != 0) 113 goto out; 114 115 /* 116 * Iterate over all elements in the nvlist, creating a new spa_t for 117 * each one with the specified configuration. 118 */ 119 mutex_enter(&spa_namespace_lock); 120 nvpair = NULL; 121 while ((nvpair = nvlist_next_nvpair(nvlist, nvpair)) != NULL) { 122 123 if (nvpair_type(nvpair) != DATA_TYPE_NVLIST) 124 continue; 125 126 VERIFY(nvpair_value_nvlist(nvpair, &child) == 0); 127 128 if (spa_lookup(nvpair_name(nvpair)) != NULL) 129 continue; 130 spa = spa_add(nvpair_name(nvpair), NULL); 131 132 /* 133 * We blindly duplicate the configuration here. If it's 134 * invalid, we will catch it when the pool is first opened. 135 */ 136 VERIFY(nvlist_dup(child, &spa->spa_config, 0) == 0); 137 } 138 mutex_exit(&spa_namespace_lock); 139 140 nvlist_free(nvlist); 141 142 out: 143 if (buf != NULL) 144 kmem_free(buf, fsize); 145 146 kobj_close_file(file); 147 } 148 149 static void 150 spa_config_write(spa_config_dirent_t *dp, nvlist_t *nvl) 151 { 152 size_t buflen; 153 char *buf; 154 vnode_t *vp; 155 int oflags = FWRITE | FTRUNC | FCREAT | FOFFMAX; 156 char *temp; 157 158 /* 159 * If the nvlist is empty (NULL), then remove the old cachefile. 160 */ 161 if (nvl == NULL) { 162 (void) vn_remove(dp->scd_path, UIO_SYSSPACE, RMFILE); 163 return; 164 } 165 166 /* 167 * Pack the configuration into a buffer. 168 */ 169 VERIFY(nvlist_size(nvl, &buflen, NV_ENCODE_XDR) == 0); 170 171 buf = kmem_alloc(buflen, KM_SLEEP); 172 temp = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 173 174 VERIFY(nvlist_pack(nvl, &buf, &buflen, NV_ENCODE_XDR, 175 KM_SLEEP) == 0); 176 177 /* 178 * Write the configuration to disk. We need to do the traditional 179 * 'write to temporary file, sync, move over original' to make sure we 180 * always have a consistent view of the data. 181 */ 182 (void) snprintf(temp, MAXPATHLEN, "%s.tmp", dp->scd_path); 183 184 if (vn_open(temp, UIO_SYSSPACE, oflags, 0644, &vp, CRCREAT, 0) == 0) { 185 if (vn_rdwr(UIO_WRITE, vp, buf, buflen, 0, UIO_SYSSPACE, 186 0, RLIM64_INFINITY, kcred, NULL) == 0 && 187 VOP_FSYNC(vp, FSYNC, kcred, NULL) == 0) { 188 (void) vn_rename(temp, dp->scd_path, UIO_SYSSPACE); 189 } 190 (void) VOP_CLOSE(vp, oflags, 1, 0, kcred, NULL); 191 VN_RELE(vp); 192 } 193 194 (void) vn_remove(temp, UIO_SYSSPACE, RMFILE); 195 196 kmem_free(buf, buflen); 197 kmem_free(temp, MAXPATHLEN); 198 } 199 200 /* 201 * Synchronize pool configuration to disk. This must be called with the 202 * namespace lock held. 203 */ 204 void 205 spa_config_sync(spa_t *target, boolean_t removing, boolean_t postsysevent) 206 { 207 spa_config_dirent_t *dp, *tdp; 208 nvlist_t *nvl; 209 210 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 211 212 if (rootdir == NULL || !(spa_mode_global & FWRITE)) 213 return; 214 215 /* 216 * Iterate over all cachefiles for the pool, past or present. When the 217 * cachefile is changed, the new one is pushed onto this list, allowing 218 * us to update previous cachefiles that no longer contain this pool. 219 */ 220 for (dp = list_head(&target->spa_config_list); dp != NULL; 221 dp = list_next(&target->spa_config_list, dp)) { 222 spa_t *spa = NULL; 223 if (dp->scd_path == NULL) 224 continue; 225 226 /* 227 * Iterate over all pools, adding any matching pools to 'nvl'. 228 */ 229 nvl = NULL; 230 while ((spa = spa_next(spa)) != NULL) { 231 if (spa == target && removing) 232 continue; 233 234 mutex_enter(&spa->spa_props_lock); 235 tdp = list_head(&spa->spa_config_list); 236 if (spa->spa_config == NULL || 237 tdp->scd_path == NULL || 238 strcmp(tdp->scd_path, dp->scd_path) != 0) { 239 mutex_exit(&spa->spa_props_lock); 240 continue; 241 } 242 243 if (nvl == NULL) 244 VERIFY(nvlist_alloc(&nvl, NV_UNIQUE_NAME, 245 KM_SLEEP) == 0); 246 247 VERIFY(nvlist_add_nvlist(nvl, spa->spa_name, 248 spa->spa_config) == 0); 249 mutex_exit(&spa->spa_props_lock); 250 } 251 252 spa_config_write(dp, nvl); 253 nvlist_free(nvl); 254 } 255 256 /* 257 * Remove any config entries older than the current one. 258 */ 259 dp = list_head(&target->spa_config_list); 260 while ((tdp = list_next(&target->spa_config_list, dp)) != NULL) { 261 list_remove(&target->spa_config_list, tdp); 262 if (tdp->scd_path != NULL) 263 spa_strfree(tdp->scd_path); 264 kmem_free(tdp, sizeof (spa_config_dirent_t)); 265 } 266 267 spa_config_generation++; 268 269 if (postsysevent) 270 spa_event_notify(target, NULL, ESC_ZFS_CONFIG_SYNC); 271 } 272 273 /* 274 * Sigh. Inside a local zone, we don't have access to /etc/zfs/zpool.cache, 275 * and we don't want to allow the local zone to see all the pools anyway. 276 * So we have to invent the ZFS_IOC_CONFIG ioctl to grab the configuration 277 * information for all pool visible within the zone. 278 */ 279 nvlist_t * 280 spa_all_configs(uint64_t *generation) 281 { 282 nvlist_t *pools; 283 spa_t *spa = NULL; 284 285 if (*generation == spa_config_generation) 286 return (NULL); 287 288 VERIFY(nvlist_alloc(&pools, NV_UNIQUE_NAME, KM_SLEEP) == 0); 289 290 mutex_enter(&spa_namespace_lock); 291 while ((spa = spa_next(spa)) != NULL) { 292 if (INGLOBALZONE(curproc) || 293 zone_dataset_visible(spa_name(spa), NULL)) { 294 mutex_enter(&spa->spa_props_lock); 295 VERIFY(nvlist_add_nvlist(pools, spa_name(spa), 296 spa->spa_config) == 0); 297 mutex_exit(&spa->spa_props_lock); 298 } 299 } 300 *generation = spa_config_generation; 301 mutex_exit(&spa_namespace_lock); 302 303 return (pools); 304 } 305 306 void 307 spa_config_set(spa_t *spa, nvlist_t *config) 308 { 309 mutex_enter(&spa->spa_props_lock); 310 if (spa->spa_config != NULL) 311 nvlist_free(spa->spa_config); 312 spa->spa_config = config; 313 mutex_exit(&spa->spa_props_lock); 314 } 315 316 /* 317 * Generate the pool's configuration based on the current in-core state. 318 * We infer whether to generate a complete config or just one top-level config 319 * based on whether vd is the root vdev. 320 */ 321 nvlist_t * 322 spa_config_generate(spa_t *spa, vdev_t *vd, uint64_t txg, int getstats) 323 { 324 nvlist_t *config, *nvroot; 325 vdev_t *rvd = spa->spa_root_vdev; 326 unsigned long hostid = 0; 327 boolean_t locked = B_FALSE; 328 329 if (vd == NULL) { 330 vd = rvd; 331 locked = B_TRUE; 332 spa_config_enter(spa, SCL_CONFIG | SCL_STATE, FTAG, RW_READER); 333 } 334 335 ASSERT(spa_config_held(spa, SCL_CONFIG | SCL_STATE, RW_READER) == 336 (SCL_CONFIG | SCL_STATE)); 337 338 /* 339 * If txg is -1, report the current value of spa->spa_config_txg. 340 */ 341 if (txg == -1ULL) 342 txg = spa->spa_config_txg; 343 344 VERIFY(nvlist_alloc(&config, NV_UNIQUE_NAME, KM_SLEEP) == 0); 345 346 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VERSION, 347 spa_version(spa)) == 0); 348 VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME, 349 spa_name(spa)) == 0); 350 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE, 351 spa_state(spa)) == 0); 352 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_TXG, 353 txg) == 0); 354 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_GUID, 355 spa_guid(spa)) == 0); 356 #ifdef _KERNEL 357 hostid = zone_get_hostid(NULL); 358 #else /* _KERNEL */ 359 /* 360 * We're emulating the system's hostid in userland, so we can't use 361 * zone_get_hostid(). 362 */ 363 (void) ddi_strtoul(hw_serial, NULL, 10, &hostid); 364 #endif /* _KERNEL */ 365 if (hostid != 0) { 366 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_HOSTID, 367 hostid) == 0); 368 } 369 VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_HOSTNAME, 370 utsname.nodename) == 0); 371 372 if (vd != rvd) { 373 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_TOP_GUID, 374 vd->vdev_top->vdev_guid) == 0); 375 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_GUID, 376 vd->vdev_guid) == 0); 377 if (vd->vdev_isspare) 378 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_IS_SPARE, 379 1ULL) == 0); 380 if (vd->vdev_islog) 381 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_IS_LOG, 382 1ULL) == 0); 383 vd = vd->vdev_top; /* label contains top config */ 384 } 385 386 /* 387 * Add the top-level config. We even add this on pools which 388 * don't support holes in the namespace as older pools will 389 * just ignore it. 390 */ 391 vdev_top_config_generate(spa, config); 392 393 nvroot = vdev_config_generate(spa, vd, getstats, B_FALSE, B_FALSE); 394 VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, nvroot) == 0); 395 nvlist_free(nvroot); 396 397 if (locked) 398 spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG); 399 400 return (config); 401 } 402 403 /* 404 * Update all disk labels, generate a fresh config based on the current 405 * in-core state, and sync the global config cache (do not sync the config 406 * cache if this is a booting rootpool). 407 */ 408 void 409 spa_config_update(spa_t *spa, int what) 410 { 411 vdev_t *rvd = spa->spa_root_vdev; 412 uint64_t txg; 413 int c; 414 415 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 416 417 spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER); 418 txg = spa_last_synced_txg(spa) + 1; 419 if (what == SPA_CONFIG_UPDATE_POOL) { 420 vdev_config_dirty(rvd); 421 } else { 422 /* 423 * If we have top-level vdevs that were added but have 424 * not yet been prepared for allocation, do that now. 425 * (It's safe now because the config cache is up to date, 426 * so it will be able to translate the new DVAs.) 427 * See comments in spa_vdev_add() for full details. 428 */ 429 for (c = 0; c < rvd->vdev_children; c++) { 430 vdev_t *tvd = rvd->vdev_child[c]; 431 if (tvd->vdev_ms_array == 0) 432 vdev_metaslab_set_size(tvd); 433 vdev_expand(tvd, txg); 434 } 435 } 436 spa_config_exit(spa, SCL_ALL, FTAG); 437 438 /* 439 * Wait for the mosconfig to be regenerated and synced. 440 */ 441 txg_wait_synced(spa->spa_dsl_pool, txg); 442 443 /* 444 * Update the global config cache to reflect the new mosconfig. 445 */ 446 if (!spa->spa_is_root) 447 spa_config_sync(spa, B_FALSE, what != SPA_CONFIG_UPDATE_POOL); 448 449 if (what == SPA_CONFIG_UPDATE_POOL) 450 spa_config_update(spa, SPA_CONFIG_UPDATE_VDEVS); 451 } 452