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 2007 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 * The configuration for all pools, in addition to being stored on disk, is 47 * stored in /etc/zfs/zpool.cache as a packed nvlist. The kernel maintains 48 * this list as pools are created, destroyed, or modified. 49 * 50 * We have a single nvlist which holds all the configuration information. When 51 * the module loads, we read this information from the cache and populate the 52 * SPA namespace. This namespace is maintained independently in spa.c. 53 * Whenever the namespace is modified, or the configuration of a pool is 54 * changed, we call spa_config_sync(), which walks through all the active pools 55 * 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_dir = ZPOOL_CACHE_DIR; 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[128]; 79 struct _buf *file; 80 uint64_t fsize; 81 82 /* 83 * Open the configuration file. 84 */ 85 (void) snprintf(pathname, sizeof (pathname), "%s%s/%s", 86 (rootdir != NULL) ? "./" : "", spa_config_dir, ZPOOL_CACHE_FILE); 87 88 file = kobj_open_file(pathname); 89 if (file == (struct _buf *)-1) 90 return; 91 92 if (kobj_get_filesize(file, &fsize) != 0) 93 goto out; 94 95 buf = kmem_alloc(fsize, KM_SLEEP); 96 97 /* 98 * Read the nvlist from the file. 99 */ 100 if (kobj_read_file(file, buf, fsize, 0) < 0) 101 goto out; 102 103 /* 104 * Unpack the nvlist. 105 */ 106 if (nvlist_unpack(buf, fsize, &nvlist, KM_SLEEP) != 0) 107 goto out; 108 109 /* 110 * Iterate over all elements in the nvlist, creating a new spa_t for 111 * each one with the specified configuration. 112 */ 113 mutex_enter(&spa_namespace_lock); 114 nvpair = NULL; 115 while ((nvpair = nvlist_next_nvpair(nvlist, nvpair)) != NULL) { 116 117 if (nvpair_type(nvpair) != DATA_TYPE_NVLIST) 118 continue; 119 120 VERIFY(nvpair_value_nvlist(nvpair, &child) == 0); 121 122 if (spa_lookup(nvpair_name(nvpair)) != NULL) 123 continue; 124 spa = spa_add(nvpair_name(nvpair), NULL); 125 126 /* 127 * We blindly duplicate the configuration here. If it's 128 * invalid, we will catch it when the pool is first opened. 129 */ 130 VERIFY(nvlist_dup(child, &spa->spa_config, 0) == 0); 131 } 132 mutex_exit(&spa_namespace_lock); 133 134 nvlist_free(nvlist); 135 136 out: 137 if (buf != NULL) 138 kmem_free(buf, fsize); 139 140 kobj_close_file(file); 141 } 142 143 /* 144 * Synchronize all pools to disk. This must be called with the namespace lock 145 * held. 146 */ 147 void 148 spa_config_sync(void) 149 { 150 spa_t *spa = NULL; 151 nvlist_t *config; 152 size_t buflen; 153 char *buf; 154 vnode_t *vp; 155 int oflags = FWRITE | FTRUNC | FCREAT | FOFFMAX; 156 char pathname[128]; 157 char pathname2[128]; 158 159 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 160 161 VERIFY(nvlist_alloc(&config, NV_UNIQUE_NAME, KM_SLEEP) == 0); 162 163 /* 164 * Add all known pools to the configuration list, ignoring those with 165 * alternate root paths. 166 */ 167 spa = NULL; 168 while ((spa = spa_next(spa)) != NULL) { 169 mutex_enter(&spa->spa_config_cache_lock); 170 if (spa->spa_config && spa->spa_name && spa->spa_root == NULL) 171 VERIFY(nvlist_add_nvlist(config, spa->spa_name, 172 spa->spa_config) == 0); 173 mutex_exit(&spa->spa_config_cache_lock); 174 } 175 176 /* 177 * Pack the configuration into a buffer. 178 */ 179 VERIFY(nvlist_size(config, &buflen, NV_ENCODE_XDR) == 0); 180 181 buf = kmem_alloc(buflen, KM_SLEEP); 182 183 VERIFY(nvlist_pack(config, &buf, &buflen, NV_ENCODE_XDR, 184 KM_SLEEP) == 0); 185 186 /* 187 * Write the configuration to disk. We need to do the traditional 188 * 'write to temporary file, sync, move over original' to make sure we 189 * always have a consistent view of the data. 190 */ 191 (void) snprintf(pathname, sizeof (pathname), "%s/%s", spa_config_dir, 192 ZPOOL_CACHE_TMP); 193 194 if (vn_open(pathname, UIO_SYSSPACE, oflags, 0644, &vp, CRCREAT, 0) != 0) 195 goto out; 196 197 if (vn_rdwr(UIO_WRITE, vp, buf, buflen, 0, UIO_SYSSPACE, 198 0, RLIM64_INFINITY, kcred, NULL) == 0 && 199 VOP_FSYNC(vp, FSYNC, kcred) == 0) { 200 (void) snprintf(pathname2, sizeof (pathname2), "%s/%s", 201 spa_config_dir, ZPOOL_CACHE_FILE); 202 (void) vn_rename(pathname, pathname2, UIO_SYSSPACE); 203 } 204 205 (void) VOP_CLOSE(vp, oflags, 1, 0, kcred); 206 VN_RELE(vp); 207 208 out: 209 (void) vn_remove(pathname, UIO_SYSSPACE, RMFILE); 210 spa_config_generation++; 211 212 kmem_free(buf, buflen); 213 nvlist_free(config); 214 } 215 216 /* 217 * Sigh. Inside a local zone, we don't have access to /etc/zfs/zpool.cache, 218 * and we don't want to allow the local zone to see all the pools anyway. 219 * So we have to invent the ZFS_IOC_CONFIG ioctl to grab the configuration 220 * information for all pool visible within the zone. 221 */ 222 nvlist_t * 223 spa_all_configs(uint64_t *generation) 224 { 225 nvlist_t *pools; 226 spa_t *spa; 227 228 if (*generation == spa_config_generation) 229 return (NULL); 230 231 VERIFY(nvlist_alloc(&pools, NV_UNIQUE_NAME, KM_SLEEP) == 0); 232 233 spa = NULL; 234 mutex_enter(&spa_namespace_lock); 235 while ((spa = spa_next(spa)) != NULL) { 236 if (INGLOBALZONE(curproc) || 237 zone_dataset_visible(spa_name(spa), NULL)) { 238 mutex_enter(&spa->spa_config_cache_lock); 239 VERIFY(nvlist_add_nvlist(pools, spa_name(spa), 240 spa->spa_config) == 0); 241 mutex_exit(&spa->spa_config_cache_lock); 242 } 243 } 244 mutex_exit(&spa_namespace_lock); 245 246 *generation = spa_config_generation; 247 248 return (pools); 249 } 250 251 void 252 spa_config_set(spa_t *spa, nvlist_t *config) 253 { 254 mutex_enter(&spa->spa_config_cache_lock); 255 if (spa->spa_config != NULL) 256 nvlist_free(spa->spa_config); 257 spa->spa_config = config; 258 mutex_exit(&spa->spa_config_cache_lock); 259 } 260 261 /* 262 * Generate the pool's configuration based on the current in-core state. 263 * We infer whether to generate a complete config or just one top-level config 264 * based on whether vd is the root vdev. 265 */ 266 nvlist_t * 267 spa_config_generate(spa_t *spa, vdev_t *vd, uint64_t txg, int getstats) 268 { 269 nvlist_t *config, *nvroot; 270 vdev_t *rvd = spa->spa_root_vdev; 271 unsigned long hostid = 0; 272 273 ASSERT(spa_config_held(spa, RW_READER)); 274 275 if (vd == NULL) 276 vd = rvd; 277 278 /* 279 * If txg is -1, report the current value of spa->spa_config_txg. 280 */ 281 if (txg == -1ULL) 282 txg = spa->spa_config_txg; 283 284 VERIFY(nvlist_alloc(&config, NV_UNIQUE_NAME, KM_SLEEP) == 0); 285 286 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VERSION, 287 spa_version(spa)) == 0); 288 VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME, 289 spa_name(spa)) == 0); 290 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE, 291 spa_state(spa)) == 0); 292 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_TXG, 293 txg) == 0); 294 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_GUID, 295 spa_guid(spa)) == 0); 296 (void) ddi_strtoul(hw_serial, NULL, 10, &hostid); 297 if (hostid != 0) { 298 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_HOSTID, 299 hostid) == 0); 300 } 301 VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_HOSTNAME, 302 utsname.nodename) == 0); 303 304 if (vd != rvd) { 305 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_TOP_GUID, 306 vd->vdev_top->vdev_guid) == 0); 307 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_GUID, 308 vd->vdev_guid) == 0); 309 if (vd->vdev_isspare) 310 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_IS_SPARE, 311 1ULL) == 0); 312 if (vd->vdev_islog) 313 VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_IS_LOG, 314 1ULL) == 0); 315 vd = vd->vdev_top; /* label contains top config */ 316 } 317 318 nvroot = vdev_config_generate(spa, vd, getstats, B_FALSE); 319 VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, nvroot) == 0); 320 nvlist_free(nvroot); 321 322 return (config); 323 } 324 325 /* 326 * Update all disk labels, generate a fresh config based on the current 327 * in-core state, and sync the global config cache. 328 */ 329 void 330 spa_config_update(spa_t *spa, int what) 331 { 332 vdev_t *rvd = spa->spa_root_vdev; 333 uint64_t txg; 334 int c; 335 336 ASSERT(MUTEX_HELD(&spa_namespace_lock)); 337 338 spa_config_enter(spa, RW_WRITER, FTAG); 339 txg = spa_last_synced_txg(spa) + 1; 340 if (what == SPA_CONFIG_UPDATE_POOL) { 341 vdev_config_dirty(rvd); 342 } else { 343 /* 344 * If we have top-level vdevs that were added but have 345 * not yet been prepared for allocation, do that now. 346 * (It's safe now because the config cache is up to date, 347 * so it will be able to translate the new DVAs.) 348 * See comments in spa_vdev_add() for full details. 349 */ 350 for (c = 0; c < rvd->vdev_children; c++) { 351 vdev_t *tvd = rvd->vdev_child[c]; 352 if (tvd->vdev_ms_array == 0) { 353 vdev_init(tvd, txg); 354 vdev_config_dirty(tvd); 355 } 356 } 357 } 358 spa_config_exit(spa, FTAG); 359 360 /* 361 * Wait for the mosconfig to be regenerated and synced. 362 */ 363 txg_wait_synced(spa->spa_dsl_pool, txg); 364 365 /* 366 * Update the global config cache to reflect the new mosconfig. 367 */ 368 spa_config_sync(); 369 370 if (what == SPA_CONFIG_UPDATE_POOL) 371 spa_config_update(spa, SPA_CONFIG_UPDATE_VDEVS); 372 } 373