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 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 /* 29 * The pool configuration repository is stored in /etc/zfs/zpool.cache as a 30 * single packed nvlist. While it would be nice to just read in this 31 * file from userland, this wouldn't work from a local zone. So we have to have 32 * a zpool ioctl to return the complete configuration for all pools. In the 33 * global zone, this will be identical to reading the file and unpacking it in 34 * userland. 35 */ 36 37 #include <errno.h> 38 #include <sys/stat.h> 39 #include <fcntl.h> 40 #include <stddef.h> 41 #include <string.h> 42 #include <unistd.h> 43 #include <libintl.h> 44 #include <libuutil.h> 45 46 #include "libzfs_impl.h" 47 48 typedef struct config_node { 49 char *cn_name; 50 nvlist_t *cn_config; 51 uu_avl_node_t cn_avl; 52 } config_node_t; 53 54 /* ARGSUSED */ 55 static int 56 config_node_compare(const void *a, const void *b, void *unused) 57 { 58 int ret; 59 60 const config_node_t *ca = (config_node_t *)a; 61 const config_node_t *cb = (config_node_t *)b; 62 63 ret = strcmp(ca->cn_name, cb->cn_name); 64 65 if (ret < 0) 66 return (-1); 67 else if (ret > 0) 68 return (1); 69 else 70 return (0); 71 } 72 73 void 74 namespace_clear(libzfs_handle_t *hdl) 75 { 76 if (hdl->libzfs_ns_avl) { 77 uu_avl_walk_t *walk; 78 config_node_t *cn; 79 80 if ((walk = uu_avl_walk_start(hdl->libzfs_ns_avl, 81 UU_WALK_ROBUST)) == NULL) 82 return; 83 84 while ((cn = uu_avl_walk_next(walk)) != NULL) { 85 uu_avl_remove(hdl->libzfs_ns_avl, cn); 86 nvlist_free(cn->cn_config); 87 free(cn->cn_name); 88 free(cn); 89 } 90 91 uu_avl_walk_end(walk); 92 93 uu_avl_destroy(hdl->libzfs_ns_avl); 94 hdl->libzfs_ns_avl = NULL; 95 } 96 97 if (hdl->libzfs_ns_avlpool) { 98 uu_avl_pool_destroy(hdl->libzfs_ns_avlpool); 99 hdl->libzfs_ns_avlpool = NULL; 100 } 101 } 102 103 /* 104 * Loads the pool namespace, or re-loads it if the cache has changed. 105 */ 106 static int 107 namespace_reload(libzfs_handle_t *hdl) 108 { 109 nvlist_t *config; 110 config_node_t *cn; 111 nvpair_t *elem; 112 zfs_cmd_t zc = { 0 }; 113 uu_avl_walk_t *walk; 114 115 if (hdl->libzfs_ns_gen == 0) { 116 /* 117 * This is the first time we've accessed the configuration 118 * cache. Initialize the AVL tree and then fall through to the 119 * common code. 120 */ 121 if ((hdl->libzfs_ns_avlpool = uu_avl_pool_create("config_pool", 122 sizeof (config_node_t), 123 offsetof(config_node_t, cn_avl), 124 config_node_compare, UU_DEFAULT)) == NULL) 125 return (no_memory(hdl)); 126 127 if ((hdl->libzfs_ns_avl = uu_avl_create(hdl->libzfs_ns_avlpool, 128 NULL, UU_DEFAULT)) == NULL) 129 return (no_memory(hdl)); 130 } 131 132 /* 133 * Issue the ZFS_IOC_POOL_CONFIGS ioctl. 134 * This can fail for one of two reasons: 135 * 136 * EEXIST The generation counts match, nothing to do. 137 * ENOMEM The zc_config_dst buffer isn't large enough to 138 * hold the config; zc_config_dst_size will have 139 * been modified to tell us how much to allocate. 140 */ 141 zc.zc_config_dst_size = 1024; 142 if ((zc.zc_config_dst = (uint64_t)(uintptr_t) 143 zfs_alloc(hdl, zc.zc_config_dst_size)) == NULL) 144 return (-1); 145 for (;;) { 146 zc.zc_cookie = hdl->libzfs_ns_gen; 147 if (ioctl(hdl->libzfs_fd, ZFS_IOC_POOL_CONFIGS, &zc) != 0) { 148 switch (errno) { 149 case EEXIST: 150 /* 151 * The namespace hasn't changed. 152 */ 153 free((void *)(uintptr_t)zc.zc_config_dst); 154 return (0); 155 156 case ENOMEM: 157 free((void *)(uintptr_t)zc.zc_config_dst); 158 if ((zc.zc_config_dst = (uint64_t)(uintptr_t) 159 zfs_alloc(hdl, zc.zc_config_dst_size)) 160 == NULL) 161 return (-1); 162 break; 163 164 default: 165 return (zfs_standard_error(hdl, errno, 166 dgettext(TEXT_DOMAIN, "failed to read " 167 "pool configuration"))); 168 } 169 } else { 170 hdl->libzfs_ns_gen = zc.zc_cookie; 171 break; 172 } 173 } 174 175 if (nvlist_unpack((void *)(uintptr_t)zc.zc_config_dst, 176 zc.zc_config_dst_size, &config, 0) != 0) 177 return (no_memory(hdl)); 178 179 free((void *)(uintptr_t)zc.zc_config_dst); 180 181 /* 182 * Clear out any existing configuration information. 183 */ 184 if ((walk = uu_avl_walk_start(hdl->libzfs_ns_avl, 185 UU_WALK_ROBUST)) == NULL) { 186 nvlist_free(config); 187 return (no_memory(hdl)); 188 } 189 190 while ((cn = uu_avl_walk_next(walk)) != NULL) { 191 uu_avl_remove(hdl->libzfs_ns_avl, cn); 192 nvlist_free(cn->cn_config); 193 free(cn->cn_name); 194 free(cn); 195 } 196 197 uu_avl_walk_end(walk); 198 199 elem = NULL; 200 while ((elem = nvlist_next_nvpair(config, elem)) != NULL) { 201 nvlist_t *child; 202 uu_avl_index_t where; 203 204 if ((cn = zfs_alloc(hdl, sizeof (config_node_t))) == NULL) { 205 nvlist_free(config); 206 return (-1); 207 } 208 209 if ((cn->cn_name = zfs_strdup(hdl, 210 nvpair_name(elem))) == NULL) { 211 free(cn); 212 return (-1); 213 } 214 215 verify(nvpair_value_nvlist(elem, &child) == 0); 216 if (nvlist_dup(child, &cn->cn_config, 0) != 0) { 217 nvlist_free(config); 218 return (no_memory(hdl)); 219 } 220 verify(uu_avl_find(hdl->libzfs_ns_avl, cn, NULL, &where) 221 == NULL); 222 223 uu_avl_insert(hdl->libzfs_ns_avl, cn, where); 224 } 225 226 nvlist_free(config); 227 return (0); 228 } 229 230 /* 231 * Retrive the configuration for the given pool. The configuration is a nvlist 232 * describing the vdevs, as well as the statistics associated with each one. 233 */ 234 nvlist_t * 235 zpool_get_config(zpool_handle_t *zhp, nvlist_t **oldconfig) 236 { 237 if (oldconfig) 238 *oldconfig = zhp->zpool_old_config; 239 return (zhp->zpool_config); 240 } 241 242 /* 243 * Refresh the vdev statistics associated with the given pool. This is used in 244 * iostat to show configuration changes and determine the delta from the last 245 * time the function was called. This function can fail, in case the pool has 246 * been destroyed. 247 */ 248 int 249 zpool_refresh_stats(zpool_handle_t *zhp) 250 { 251 zfs_cmd_t zc = { 0 }; 252 int error; 253 nvlist_t *config; 254 255 (void) strcpy(zc.zc_name, zhp->zpool_name); 256 257 if (zhp->zpool_config_size == 0) 258 zhp->zpool_config_size = 1 << 16; 259 260 zc.zc_config_dst_size = zhp->zpool_config_size; 261 if ((zc.zc_config_dst = (uint64_t)(uintptr_t) 262 zfs_alloc(zhp->zpool_hdl, zc.zc_config_dst_size)) == NULL) 263 return (-1); 264 265 for (;;) { 266 if (ioctl(zhp->zpool_hdl->libzfs_fd, ZFS_IOC_POOL_STATS, 267 &zc) == 0) { 268 /* 269 * The real error is returned in the zc_cookie field. 270 */ 271 error = errno = zc.zc_cookie; 272 break; 273 } 274 275 if (errno == ENOMEM) { 276 free((void *)(uintptr_t)zc.zc_config_dst); 277 if ((zc.zc_config_dst = (uint64_t)(uintptr_t) 278 zfs_alloc(zhp->zpool_hdl, 279 zc.zc_config_dst_size)) == NULL) 280 return (-1); 281 } else { 282 free((void *)(uintptr_t)zc.zc_config_dst); 283 return (-1); 284 } 285 } 286 287 if (nvlist_unpack((void *)(uintptr_t)zc.zc_config_dst, 288 zc.zc_config_dst_size, &config, 0) != 0) { 289 free((void *)(uintptr_t)zc.zc_config_dst); 290 return (no_memory(zhp->zpool_hdl)); 291 } 292 293 zhp->zpool_config_size = zc.zc_config_dst_size; 294 free((void *)(uintptr_t)zc.zc_config_dst); 295 296 if (set_pool_health(config) != 0) 297 return (no_memory(zhp->zpool_hdl)); 298 299 if (zhp->zpool_config != NULL) { 300 uint64_t oldtxg, newtxg; 301 302 verify(nvlist_lookup_uint64(zhp->zpool_config, 303 ZPOOL_CONFIG_POOL_TXG, &oldtxg) == 0); 304 verify(nvlist_lookup_uint64(config, 305 ZPOOL_CONFIG_POOL_TXG, &newtxg) == 0); 306 307 if (zhp->zpool_old_config != NULL) 308 nvlist_free(zhp->zpool_old_config); 309 310 if (oldtxg != newtxg) { 311 nvlist_free(zhp->zpool_config); 312 zhp->zpool_old_config = NULL; 313 } else { 314 zhp->zpool_old_config = zhp->zpool_config; 315 } 316 } 317 318 zhp->zpool_config = config; 319 320 return (error ? -1 : 0); 321 } 322 323 /* 324 * Iterate over all pools in the system. 325 */ 326 int 327 zpool_iter(libzfs_handle_t *hdl, zpool_iter_f func, void *data) 328 { 329 config_node_t *cn; 330 zpool_handle_t *zhp; 331 int ret; 332 333 if (namespace_reload(hdl) != 0) 334 return (-1); 335 336 for (cn = uu_avl_first(hdl->libzfs_ns_avl); cn != NULL; 337 cn = uu_avl_next(hdl->libzfs_ns_avl, cn)) { 338 339 if ((zhp = zpool_open_silent(hdl, cn->cn_name)) == NULL) 340 continue; 341 342 if ((ret = func(zhp, data)) != 0) 343 return (ret); 344 } 345 346 return (0); 347 } 348 349 /* 350 * Iterate over root datasets, calling the given function for each. The zfs 351 * handle passed each time must be explicitly closed by the callback. 352 */ 353 int 354 zfs_iter_root(libzfs_handle_t *hdl, zfs_iter_f func, void *data) 355 { 356 config_node_t *cn; 357 zfs_handle_t *zhp; 358 int ret; 359 360 if (namespace_reload(hdl) != 0) 361 return (-1); 362 363 for (cn = uu_avl_first(hdl->libzfs_ns_avl); cn != NULL; 364 cn = uu_avl_next(hdl->libzfs_ns_avl, cn)) { 365 366 if ((zhp = make_dataset_handle(hdl, cn->cn_name)) == NULL) 367 continue; 368 369 if ((ret = func(zhp, data)) != 0) 370 return (ret); 371 } 372 373 return (0); 374 } 375