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 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 #include <sys/spa.h> 30 #include <sys/spa_impl.h> 31 #include <sys/nvpair.h> 32 #include <sys/uio.h> 33 #include <sys/fs/zfs.h> 34 #include <sys/vdev_impl.h> 35 #include <sys/zfs_ioctl.h> 36 #include <sys/utsname.h> 37 #include <sys/systeminfo.h> 38 #include <sys/sunddi.h> 39 #ifdef _KERNEL 40 #include <sys/kobj.h> 41 #endif 42 43 /* 44 * Pool configuration repository. 45 * 46 * Pool configuration is stored as a packed nvlist on the filesystem. By 47 * default, all pools are stored in /etc/zfs/zpool.cache and loaded on boot 48 * (when the ZFS module is loaded). Pools can also have the 'cachefile' 49 * property set that allows them to be stored in an alternate location until 50 * the control of external software. 51 * 52 * For each cache file, we have a single nvlist which holds all the 53 * configuration information. When the module loads, we read this information 54 * from /etc/zfs/zpool.cache and populate the SPA namespace. This namespace is 55 * maintained independently in spa.c. Whenever the namespace is modified, or 56 * the configuration of a pool is changed, we call spa_config_sync(), which 57 * walks through all the active pools and writes the configuration to disk. 58 */ 59 60 static uint64_t spa_config_generation = 1; 61 62 /* 63 * This can be overridden in userland to preserve an alternate namespace for 64 * userland pools when doing testing. 65 */ 66 const char *spa_config_path = ZPOOL_CACHE; 67 68 /* 69 * Called when the module is first loaded, this routine loads the configuration 70 * file into the SPA namespace. It does not actually open or load the pools; it 71 * only populates the namespace. 72 */ 73 void 74 spa_config_load(void) 75 { 76 void *buf = NULL; 77 nvlist_t *nvlist, *child; 78 nvpair_t *nvpair; 79 spa_t *spa; 80 char pathname[128]; 81 struct _buf *file; 82 uint64_t fsize; 83 84 /* 85 * Open the configuration file. 86 */ 87 (void) snprintf(pathname, sizeof (pathname), "%s%s", 88 (rootdir != NULL) ? "./" : "", spa_config_path); 89 90 file = kobj_open_file(pathname); 91 if (file == (struct _buf *)-1) 92 return; 93 94 if (kobj_get_filesize(file, &fsize) != 0) 95 goto out; 96 97 buf = kmem_alloc(fsize, KM_SLEEP); 98 99 /* 100 * Read the nvlist from the file. 101 */ 102 if (kobj_read_file(file, buf, fsize, 0) < 0) 103 goto out; 104 105 /* 106 * Unpack the nvlist. 107 */ 108 if (nvlist_unpack(buf, fsize, &nvlist, KM_SLEEP) != 0) 109 goto out; 110 111 /* 112 * Iterate over all elements in the nvlist, creating a new spa_t for 113 * each one with the specified configuration. 114 */ 115 mutex_enter(&spa_namespace_lock); 116 nvpair = NULL; 117 while ((nvpair = nvlist_next_nvpair(nvlist, nvpair)) != NULL) { 118 119 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 spa = spa_add(nvpair_name(nvpair), NULL); 127 128 /* 129 * We blindly duplicate the configuration here. If it's 130 * invalid, we will catch it when the pool is first opened. 131 */ 132 VERIFY(nvlist_dup(child, &spa->spa_config, 0) == 0); 133 } 134 mutex_exit(&spa_namespace_lock); 135 136 nvlist_free(nvlist); 137 138 out: 139 if (buf != NULL) 140 kmem_free(buf, fsize); 141 142 kobj_close_file(file); 143 } 144 145 static void 146 spa_config_write(spa_config_dirent_t *dp, nvlist_t *nvl) 147 { 148 size_t buflen; 149 char *buf; 150 vnode_t *vp; 151 int oflags = FWRITE | FTRUNC | FCREAT | FOFFMAX; 152 char tempname[128]; 153 154 /* 155 * If the nvlist is empty (NULL), then remove the old cachefile. 156 */ 157 if (nvl == NULL) { 158 (void) vn_remove(dp->scd_path, UIO_SYSSPACE, RMFILE); 159 return; 160 } 161 162 /* 163 * Pack the configuration into a buffer. 164 */ 165 VERIFY(nvlist_size(nvl, &buflen, NV_ENCODE_XDR) == 0); 166 167 buf = kmem_alloc(buflen, KM_SLEEP); 168 169 VERIFY(nvlist_pack(nvl, &buf, &buflen, NV_ENCODE_XDR, 170 KM_SLEEP) == 0); 171 172 /* 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. 176 */ 177 (void) snprintf(tempname, sizeof (tempname), "%s.tmp", dp->scd_path); 178 179 if (vn_open(tempname, UIO_SYSSPACE, oflags, 0644, &vp, CRCREAT, 0) != 0) 180 goto out; 181 182 if (vn_rdwr(UIO_WRITE, vp, buf, buflen, 0, UIO_SYSSPACE, 183 0, RLIM64_INFINITY, kcred, NULL) == 0 && 184 VOP_FSYNC(vp, FSYNC, kcred, NULL) == 0) { 185 (void) vn_rename(tempname, dp->scd_path, UIO_SYSSPACE); 186 } 187 188 (void) VOP_CLOSE(vp, oflags, 1, 0, kcred, NULL); 189 VN_RELE(vp); 190 191 out: 192 (void) vn_remove(tempname, UIO_SYSSPACE, RMFILE); 193 kmem_free(buf, buflen); 194 } 195 196 /* 197 * Synchronize pool configuration to disk. This must be called with the 198 * namespace lock held. 199 */ 200 void 201 spa_config_sync(spa_t *target, boolean_t removing, boolean_t postsysevent) 202 { 203 spa_t *spa = NULL; 204 spa_config_dirent_t *dp, *tdp; 205 nvlist_t *nvl; 206 207 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 208 209 /* 210 * Iterate over all cachefiles for the pool, past or present. When the 211 * cachefile is changed, the new one is pushed onto this list, allowing 212 * us to update previous cachefiles that no longer contain this pool. 213 */ 214 for (dp = list_head(&target->spa_config_list); dp != NULL; 215 dp = list_next(&target->spa_config_list, dp)) { 216 spa = NULL; 217 if (dp->scd_path == NULL) 218 continue; 219 220 /* 221 * Iterate over all pools, adding any matching pools to 'nvl'. 222 */ 223 nvl = NULL; 224 while ((spa = spa_next(spa)) != NULL) { 225 if (spa->spa_config == NULL || spa->spa_name == NULL) 226 continue; 227 228 if (spa == target && removing) 229 continue; 230 231 tdp = list_head(&spa->spa_config_list); 232 ASSERT(tdp != NULL); 233 if (tdp->scd_path == NULL || 234 strcmp(tdp->scd_path, dp->scd_path) != 0) 235 continue; 236 237 if (nvl == NULL) 238 VERIFY(nvlist_alloc(&nvl, NV_UNIQUE_NAME, 239 KM_SLEEP) == 0); 240 241 VERIFY(nvlist_add_nvlist(nvl, spa->spa_name, 242 spa->spa_config) == 0); 243 } 244 245 spa_config_write(dp, nvl); 246 nvlist_free(nvl); 247 } 248 249 /* 250 * Remove any config entries older than the current one. 251 */ 252 dp = list_head(&target->spa_config_list); 253 while ((tdp = list_next(&target->spa_config_list, dp)) != NULL) { 254 list_remove(&target->spa_config_list, tdp); 255 if (tdp->scd_path != NULL) 256 spa_strfree(tdp->scd_path); 257 kmem_free(tdp, sizeof (spa_config_dirent_t)); 258 } 259 260 spa_config_generation++; 261 262 if (postsysevent) 263 spa_event_notify(target, NULL, ESC_ZFS_CONFIG_SYNC); 264 } 265 266 /* 267 * Sigh. Inside a local zone, we don't have access to /etc/zfs/zpool.cache, 268 * and we don't want to allow the local zone to see all the pools anyway. 269 * So we have to invent the ZFS_IOC_CONFIG ioctl to grab the configuration 270 * information for all pool visible within the zone. 271 */ 272 nvlist_t * 273 spa_all_configs(uint64_t *generation) 274 { 275 nvlist_t *pools; 276 spa_t *spa; 277 278 if (*generation == spa_config_generation) 279 return (NULL); 280 281 VERIFY(nvlist_alloc(&pools, NV_UNIQUE_NAME, KM_SLEEP) == 0); 282 283 spa = NULL; 284 mutex_enter(&spa_namespace_lock); 285 while ((spa = spa_next(spa)) != NULL) { 286 if (INGLOBALZONE(curproc) || 287 zone_dataset_visible(spa_name(spa), NULL)) { 288 mutex_enter(&spa->spa_config_cache_lock); 289 VERIFY(nvlist_add_nvlist(pools, spa_name(spa), 290 spa->spa_config) == 0); 291 mutex_exit(&spa->spa_config_cache_lock); 292 } 293 } 294 mutex_exit(&spa_namespace_lock); 295 296 *generation = spa_config_generation; 297 298 return (pools); 299 } 300 301 void 302 spa_config_set(spa_t *spa, nvlist_t *config) 303 { 304 mutex_enter(&spa->spa_config_cache_lock); 305 if (spa->spa_config != NULL) 306 nvlist_free(spa->spa_config); 307 spa->spa_config = config; 308 mutex_exit(&spa->spa_config_cache_lock); 309 } 310 311 /* 312 * Generate the pool's configuration based on the current in-core state. 313 * We infer whether to generate a complete config or just one top-level config 314 * based on whether vd is the root vdev. 315 */ 316 nvlist_t * 317 spa_config_generate(spa_t *spa, vdev_t *vd, uint64_t txg, int getstats) 318 { 319 nvlist_t *config, *nvroot; 320 vdev_t *rvd = spa->spa_root_vdev; 321 unsigned long hostid = 0; 322 323 ASSERT(spa_config_held(spa, RW_READER) || 324 spa_config_held(spa, RW_WRITER)); 325 326 if (vd == NULL) 327 vd = rvd; 328 329 /* 330 * If txg is -1, report the current value of spa->spa_config_txg. 331 */ 332 if (txg == -1ULL) 333 txg = spa->spa_config_txg; 334 335 VERIFY(nvlist_alloc(&config, NV_UNIQUE_NAME, KM_SLEEP) == 0); 336 337 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VERSION, 338 spa_version(spa)) == 0); 339 VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME, 340 spa_name(spa)) == 0); 341 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE, 342 spa_state(spa)) == 0); 343 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_TXG, 344 txg) == 0); 345 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_GUID, 346 spa_guid(spa)) == 0); 347 (void) ddi_strtoul(hw_serial, NULL, 10, &hostid); 348 if (hostid != 0) { 349 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_HOSTID, 350 hostid) == 0); 351 } 352 VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_HOSTNAME, 353 utsname.nodename) == 0); 354 355 if (vd != rvd) { 356 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_TOP_GUID, 357 vd->vdev_top->vdev_guid) == 0); 358 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_GUID, 359 vd->vdev_guid) == 0); 360 if (vd->vdev_isspare) 361 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_IS_SPARE, 362 1ULL) == 0); 363 if (vd->vdev_islog) 364 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_IS_LOG, 365 1ULL) == 0); 366 vd = vd->vdev_top; /* label contains top config */ 367 } 368 369 nvroot = vdev_config_generate(spa, vd, getstats, B_FALSE, B_FALSE); 370 VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, nvroot) == 0); 371 nvlist_free(nvroot); 372 373 return (config); 374 } 375 376 /* 377 * For a pool that's not currently a booting rootpool, update all disk labels, 378 * generate a fresh config based on the current in-core state, and sync the 379 * global config cache. 380 */ 381 void 382 spa_config_update(spa_t *spa, int what) 383 { 384 spa_config_update_common(spa, what, FALSE); 385 } 386 387 /* 388 * Update all disk labels, generate a fresh config based on the current 389 * in-core state, and sync the global config cache (do not sync the config 390 * cache if this is a booting rootpool). 391 */ 392 void 393 spa_config_update_common(spa_t *spa, int what, boolean_t isroot) 394 { 395 vdev_t *rvd = spa->spa_root_vdev; 396 uint64_t txg; 397 int c; 398 399 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 400 401 spa_config_enter(spa, RW_WRITER, FTAG); 402 txg = spa_last_synced_txg(spa) + 1; 403 if (what == SPA_CONFIG_UPDATE_POOL) { 404 vdev_config_dirty(rvd); 405 } else { 406 /* 407 * If we have top-level vdevs that were added but have 408 * not yet been prepared for allocation, do that now. 409 * (It's safe now because the config cache is up to date, 410 * so it will be able to translate the new DVAs.) 411 * See comments in spa_vdev_add() for full details. 412 */ 413 for (c = 0; c < rvd->vdev_children; c++) { 414 vdev_t *tvd = rvd->vdev_child[c]; 415 if (tvd->vdev_ms_array == 0) { 416 vdev_init(tvd, txg); 417 vdev_config_dirty(tvd); 418 } 419 } 420 } 421 spa_config_exit(spa, FTAG); 422 423 /* 424 * Wait for the mosconfig to be regenerated and synced. 425 */ 426 txg_wait_synced(spa->spa_dsl_pool, txg); 427 428 /* 429 * Update the global config cache to reflect the new mosconfig. 430 */ 431 if (!isroot) 432 spa_config_sync(spa, B_FALSE, what != SPA_CONFIG_UPDATE_POOL); 433 434 if (what == SPA_CONFIG_UPDATE_POOL) 435 spa_config_update_common(spa, SPA_CONFIG_UPDATE_VDEVS, isroot); 436 } 437