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