lib/libzfs/libzfs_import.c

   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 2010 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 /*
  27  * Pool import support functions.
  28  *
  29  * To import a pool, we rely on reading the configuration information from the
  30  * ZFS label of each device.  If we successfully read the label, then we
  31  * organize the configuration information in the following hierarchy:
  32  *
  33  *      pool guid -> toplevel vdev guid -> label txg
  34  *
  35  * Duplicate entries matching this same tuple will be discarded.  Once we have
  36  * examined every device, we pick the best label txg config for each toplevel
  37  * vdev.  We then arrange these toplevel vdevs into a complete pool config, and
  38  * update any paths that have changed.  Finally, we attempt to import the pool
  39  * using our derived config, and record the results.
  40  */
  41
  42 #include <ctype.h>
  43 #include <devid.h>
  44 #include <dirent.h>
  45 #include <errno.h>
  46 #include <libintl.h>
  47 #include <stddef.h>
  48 #include <stdlib.h>
  49 #include <string.h>
  50 #include <sys/stat.h>
  51 #include <unistd.h>
  52 #include <fcntl.h>
  53 #include <sys/vtoc.h>
  54 #include <sys/dktp/fdisk.h>
  55 #include <sys/efi_partition.h>
  56 #include <thread_pool.h>
  57
  58 #include <sys/vdev_impl.h>
  59
  60 #include "libzfs.h"
  61 #include "libzfs_impl.h"
  62
  63 /*
  64  * Intermediate structures used to gather configuration information.
  65  */
  66 typedef struct config_entry {
  67         uint64_t                ce_txg;
  68         nvlist_t                *ce_config;
  69         struct config_entry     *ce_next;
  70 } config_entry_t;
  71
  72 typedef struct vdev_entry {
  73         uint64_t                ve_guid;
  74         config_entry_t          *ve_configs;
  75         struct vdev_entry       *ve_next;
  76 } vdev_entry_t;
  77
  78 typedef struct pool_entry {
  79         uint64_t                pe_guid;
  80         vdev_entry_t            *pe_vdevs;
  81         struct pool_entry       *pe_next;
  82 } pool_entry_t;
  83
  84 typedef struct name_entry {
  85         char                    *ne_name;
  86         uint64_t                ne_guid;
  87         struct name_entry       *ne_next;
  88 } name_entry_t;
  89
  90 typedef struct pool_list {
  91         pool_entry_t            *pools;
  92         name_entry_t            *names;
  93 } pool_list_t;
  94
  95 static char *
  96 get_devid(const char *path)
  97 {
  98         int fd;
  99         ddi_devid_t devid;
 100         char *minor, *ret;
 101
 102         if ((fd = open(path, O_RDONLY)) < 0)
 103                 return (NULL);
 104
 105         minor = NULL;
 106         ret = NULL;
 107         if (devid_get(fd, &devid) == 0) {
 108                 if (devid_get_minor_name(fd, &minor) == 0)
 109                         ret = devid_str_encode(devid, minor);
 110                 if (minor != NULL)
 111                         devid_str_free(minor);
 112                 devid_free(devid);
 113         }
 114         (void) close(fd);
 115
 116         return (ret);
 117 }
 118
 119
 120 /*
 121  * Go through and fix up any path and/or devid information for the given vdev
 122  * configuration.
 123  */
 124 static int
 125 fix_paths(nvlist_t *nv, name_entry_t *names)
 126 {
 127         nvlist_t **child;
 128         uint_t c, children;
 129         uint64_t guid;
 130         name_entry_t *ne, *best;
 131         char *path, *devid;
 132         int matched;
 133
 134         if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
 135             &child, &children) == 0) {
 136                 for (c = 0; c < children; c++)
 137                         if (fix_paths(child[c], names) != 0)
 138                                 return (-1);
 139                 return (0);
 140         }
 141
 142         /*
 143          * This is a leaf (file or disk) vdev.  In either case, go through
 144          * the name list and see if we find a matching guid.  If so, replace
 145          * the path and see if we can calculate a new devid.
 146          *
 147          * There may be multiple names associated with a particular guid, in
 148          * which case we have overlapping slices or multiple paths to the same
 149          * disk.  If this is the case, then we want to pick the path that is
 150          * the most similar to the original, where "most similar" is the number
 151          * of matching characters starting from the end of the path.  This will
 152          * preserve slice numbers even if the disks have been reorganized, and
 153          * will also catch preferred disk names if multiple paths exist.
 154          */
 155         verify(nvlist_lookup_uint64(nv, ZPOOL_CONFIG_GUID, &guid) == 0);
 156         if (nvlist_lookup_string(nv, ZPOOL_CONFIG_PATH, &path) != 0)
 157                 path = NULL;
 158
 159         matched = 0;
 160         best = NULL;
 161         for (ne = names; ne != NULL; ne = ne->ne_next) {
 162                 if (ne->ne_guid == guid) {
 163                         const char *src, *dst;
 164                         int count;
 165
 166                         if (path == NULL) {
 167                                 best = ne;
 168                                 break;
 169                         }
 170
 171                         src = ne->ne_name + strlen(ne->ne_name) - 1;
 172                         dst = path + strlen(path) - 1;
 173                         for (count = 0; src >= ne->ne_name && dst >= path;
 174                             src--, dst--, count++)
 175                                 if (*src != *dst)
 176                                         break;
 177
 178                         /*
 179                          * At this point, 'count' is the number of characters
 180                          * matched from the end.
 181                          */
 182                         if (count > matched || best == NULL) {
 183                                 best = ne;
 184                                 matched = count;
 185                         }
 186                 }
 187         }
 188
 189         if (best == NULL)
 190                 return (0);
 191
 192         if (nvlist_add_string(nv, ZPOOL_CONFIG_PATH, best->ne_name) != 0)
 193                 return (-1);
 194
 195         if ((devid = get_devid(best->ne_name)) == NULL) {
 196                 (void) nvlist_remove_all(nv, ZPOOL_CONFIG_DEVID);
 197         } else {
 198                 if (nvlist_add_string(nv, ZPOOL_CONFIG_DEVID, devid) != 0)
 199                         return (-1);
 200                 devid_str_free(devid);
 201         }
 202
 203         return (0);
 204 }
 205
 206 /*
 207  * Add the given configuration to the list of known devices.
 208  */
 209 static int
 210 add_config(libzfs_handle_t *hdl, pool_list_t *pl, const char *path,
 211     nvlist_t *config)
 212 {
 213         uint64_t pool_guid, vdev_guid, top_guid, txg, state;
 214         pool_entry_t *pe;
 215         vdev_entry_t *ve;
 216         config_entry_t *ce;
 217         name_entry_t *ne;
 218
 219         /*
 220          * If this is a hot spare not currently in use or level 2 cache
 221          * device, add it to the list of names to translate, but don't do
 222          * anything else.
 223          */
 224         if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_STATE,
 225             &state) == 0 &&
 226             (state == POOL_STATE_SPARE || state == POOL_STATE_L2CACHE) &&
 227             nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID, &vdev_guid) == 0) {
 228                 if ((ne = zfs_alloc(hdl, sizeof (name_entry_t))) == NULL)
 229                         return (-1);
 230
 231                 if ((ne->ne_name = zfs_strdup(hdl, path)) == NULL) {
 232                         free(ne);
 233                         return (-1);
 234                 }
 235                 ne->ne_guid = vdev_guid;
 236                 ne->ne_next = pl->names;
 237                 pl->names = ne;
 238                 return (0);
 239         }
 240
 241         /*
 242          * If we have a valid config but cannot read any of these fields, then
 243          * it means we have a half-initialized label.  In vdev_label_init()
 244          * we write a label with txg == 0 so that we can identify the device
 245          * in case the user refers to the same disk later on.  If we fail to
 246          * create the pool, we'll be left with a label in this state
 247          * which should not be considered part of a valid pool.
 248          */
 249         if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
 250             &pool_guid) != 0 ||
 251             nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID,
 252             &vdev_guid) != 0 ||
 253             nvlist_lookup_uint64(config, ZPOOL_CONFIG_TOP_GUID,
 254             &top_guid) != 0 ||
 255             nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_TXG,
 256             &txg) != 0 || txg == 0) {
 257                 nvlist_free(config);
 258                 return (0);
 259         }
 260
 261         /*
 262          * First, see if we know about this pool.  If not, then add it to the
 263          * list of known pools.
 264          */
 265         for (pe = pl->pools; pe != NULL; pe = pe->pe_next) {
 266                 if (pe->pe_guid == pool_guid)
 267                         break;
 268         }
 269
 270         if (pe == NULL) {
 271                 if ((pe = zfs_alloc(hdl, sizeof (pool_entry_t))) == NULL) {
 272                         nvlist_free(config);
 273                         return (-1);
 274                 }
 275                 pe->pe_guid = pool_guid;
 276                 pe->pe_next = pl->pools;
 277                 pl->pools = pe;
 278         }
 279
 280         /*
 281          * Second, see if we know about this toplevel vdev.  Add it if its
 282          * missing.
 283          */
 284         for (ve = pe->pe_vdevs; ve != NULL; ve = ve->ve_next) {
 285                 if (ve->ve_guid == top_guid)
 286                         break;
 287         }
 288
 289         if (ve == NULL) {
 290                 if ((ve = zfs_alloc(hdl, sizeof (vdev_entry_t))) == NULL) {
 291                         nvlist_free(config);
 292                         return (-1);
 293                 }
 294                 ve->ve_guid = top_guid;
 295                 ve->ve_next = pe->pe_vdevs;
 296                 pe->pe_vdevs = ve;
 297         }
 298
 299         /*
 300          * Third, see if we have a config with a matching transaction group.  If
 301          * so, then we do nothing.  Otherwise, add it to the list of known
 302          * configs.
 303          */
 304         for (ce = ve->ve_configs; ce != NULL; ce = ce->ce_next) {
 305                 if (ce->ce_txg == txg)
 306                         break;
 307         }
 308
 309         if (ce == NULL) {
 310                 if ((ce = zfs_alloc(hdl, sizeof (config_entry_t))) == NULL) {
 311                         nvlist_free(config);
 312                         return (-1);
 313                 }
 314                 ce->ce_txg = txg;
 315                 ce->ce_config = config;
 316                 ce->ce_next = ve->ve_configs;
 317                 ve->ve_configs = ce;
 318         } else {
 319                 nvlist_free(config);
 320         }
 321
 322         /*
 323          * At this point we've successfully added our config to the list of
 324          * known configs.  The last thing to do is add the vdev guid -> path
 325          * mappings so that we can fix up the configuration as necessary before
 326          * doing the import.
 327          */
 328         if ((ne = zfs_alloc(hdl, sizeof (name_entry_t))) == NULL)
 329                 return (-1);
 330
 331         if ((ne->ne_name = zfs_strdup(hdl, path)) == NULL) {
 332                 free(ne);
 333                 return (-1);
 334         }
 335
 336         ne->ne_guid = vdev_guid;
 337         ne->ne_next = pl->names;
 338         pl->names = ne;
 339
 340         return (0);
 341 }
 342
 343 /*
 344  * Returns true if the named pool matches the given GUID.
 345  */
 346 static int
 347 pool_active(libzfs_handle_t *hdl, const char *name, uint64_t guid,
 348     boolean_t *isactive)
 349 {
 350         zpool_handle_t *zhp;
 351         uint64_t theguid;
 352
 353         if (zpool_open_silent(hdl, name, &zhp) != 0)
 354                 return (-1);
 355
 356         if (zhp == NULL) {
 357                 *isactive = B_FALSE;
 358                 return (0);
 359         }
 360
 361         verify(nvlist_lookup_uint64(zhp->zpool_config, ZPOOL_CONFIG_POOL_GUID,
 362             &theguid) == 0);
 363
 364         zpool_close(zhp);
 365
 366         *isactive = (theguid == guid);
 367         return (0);
 368 }
 369
 370 static nvlist_t *
 371 refresh_config(libzfs_handle_t *hdl, nvlist_t *config)
 372 {
 373         nvlist_t *nvl;
 374         zfs_cmd_t zc = { 0 };
 375         int err;
 376
 377         if (zcmd_write_conf_nvlist(hdl, &zc, config) != 0)
 378                 return (NULL);
 379
 380         if (zcmd_alloc_dst_nvlist(hdl, &zc,
 381             zc.zc_nvlist_conf_size * 2) != 0) {
 382                 zcmd_free_nvlists(&zc);
 383                 return (NULL);
 384         }
 385
 386         while ((err = ioctl(hdl->libzfs_fd, ZFS_IOC_POOL_TRYIMPORT,
 387             &zc)) != 0 && errno == ENOMEM) {
 388                 if (zcmd_expand_dst_nvlist(hdl, &zc) != 0) {
 389                         zcmd_free_nvlists(&zc);
 390                         return (NULL);
 391                 }
 392         }
 393
 394         if (err) {
 395                 zcmd_free_nvlists(&zc);
 396                 return (NULL);
 397         }
 398
 399         if (zcmd_read_dst_nvlist(hdl, &zc, &nvl) != 0) {
 400                 zcmd_free_nvlists(&zc);
 401                 return (NULL);
 402         }
 403
 404         zcmd_free_nvlists(&zc);
 405         return (nvl);
 406 }
 407
 408 /*
 409  * Determine if the vdev id is a hole in the namespace.
 410  */
 411 boolean_t
 412 vdev_is_hole(uint64_t *hole_array, uint_t holes, uint_t id)
 413 {
 414         for (int c = 0; c < holes; c++) {
 415
 416                 /* Top-level is a hole */
 417                 if (hole_array[c] == id)
 418                         return (B_TRUE);
 419         }
 420         return (B_FALSE);
 421 }
 422
 423 /*
 424  * Convert our list of pools into the definitive set of configurations.  We
 425  * start by picking the best config for each toplevel vdev.  Once that's done,
 426  * we assemble the toplevel vdevs into a full config for the pool.  We make a
 427  * pass to fix up any incorrect paths, and then add it to the main list to
 428  * return to the user.
 429  */
 430 static nvlist_t *
 431 get_configs(libzfs_handle_t *hdl, pool_list_t *pl, boolean_t active_ok)
 432 {
 433         pool_entry_t *pe;
 434         vdev_entry_t *ve;
 435         config_entry_t *ce;
 436         nvlist_t *ret = NULL, *config = NULL, *tmp, *nvtop, *nvroot;
 437         nvlist_t **spares, **l2cache;
 438         uint_t i, nspares, nl2cache;
 439         boolean_t config_seen;
 440         uint64_t best_txg;
 441         char *name, *hostname;
 442         uint64_t version, guid;
 443         uint_t children = 0;
 444         nvlist_t **child = NULL;
 445         uint_t holes;
 446         uint64_t *hole_array, max_id;
 447         uint_t c;
 448         boolean_t isactive;
 449         uint64_t hostid;
 450         nvlist_t *nvl;
 451         boolean_t found_one = B_FALSE;
 452         boolean_t valid_top_config = B_FALSE;
 453
 454         if (nvlist_alloc(&ret, 0, 0) != 0)
 455                 goto nomem;
 456
 457         for (pe = pl->pools; pe != NULL; pe = pe->pe_next) {
 458                 uint64_t id, max_txg = 0;
 459
 460                 if (nvlist_alloc(&config, NV_UNIQUE_NAME, 0) != 0)
 461                         goto nomem;
 462                 config_seen = B_FALSE;
 463
 464                 /*
 465                  * Iterate over all toplevel vdevs.  Grab the pool configuration
 466                  * from the first one we find, and then go through the rest and
 467                  * add them as necessary to the 'vdevs' member of the config.
 468                  */
 469                 for (ve = pe->pe_vdevs; ve != NULL; ve = ve->ve_next) {
 470
 471                         /*
 472                          * Determine the best configuration for this vdev by
 473                          * selecting the config with the latest transaction
 474                          * group.
 475                          */
 476                         best_txg = 0;
 477                         for (ce = ve->ve_configs; ce != NULL;
 478                             ce = ce->ce_next) {
 479
 480                                 if (ce->ce_txg > best_txg) {
 481                                         tmp = ce->ce_config;
 482                                         best_txg = ce->ce_txg;
 483                                 }
 484                         }
 485
 486                         /*
 487                          * We rely on the fact that the max txg for the
 488                          * pool will contain the most up-to-date information
 489                          * about the valid top-levels in the vdev namespace.
 490                          */
 491                         if (best_txg > max_txg) {
 492                                 (void) nvlist_remove(config,
 493                                     ZPOOL_CONFIG_VDEV_CHILDREN,
 494                                     DATA_TYPE_UINT64);
 495                                 (void) nvlist_remove(config,
 496                                     ZPOOL_CONFIG_HOLE_ARRAY,
 497                                     DATA_TYPE_UINT64_ARRAY);
 498
 499                                 max_txg = best_txg;
 500                                 hole_array = NULL;
 501                                 holes = 0;
 502                                 max_id = 0;
 503                                 valid_top_config = B_FALSE;
 504
 505                                 if (nvlist_lookup_uint64(tmp,
 506                                     ZPOOL_CONFIG_VDEV_CHILDREN, &max_id) == 0) {
 507                                         verify(nvlist_add_uint64(config,
 508                                             ZPOOL_CONFIG_VDEV_CHILDREN,
 509                                             max_id) == 0);
 510                                         valid_top_config = B_TRUE;
 511                                 }
 512
 513                                 if (nvlist_lookup_uint64_array(tmp,
 514                                     ZPOOL_CONFIG_HOLE_ARRAY, &hole_array,
 515                                     &holes) == 0) {
 516                                         verify(nvlist_add_uint64_array(config,
 517                                             ZPOOL_CONFIG_HOLE_ARRAY,
 518                                             hole_array, holes) == 0);
 519                                 }
 520                         }
 521
 522                         if (!config_seen) {
 523                                 /*
 524                                  * Copy the relevant pieces of data to the pool
 525                                  * configuration:
 526                                  *
 527                                  *      version
 528                                  *      pool guid
 529                                  *      name
 530                                  *      pool state
 531                                  *      hostid (if available)
 532                                  *      hostname (if available)
 533                                  */
 534                                 uint64_t state;
 535
 536                                 verify(nvlist_lookup_uint64(tmp,
 537                                     ZPOOL_CONFIG_VERSION, &version) == 0);
 538                                 if (nvlist_add_uint64(config,
 539                                     ZPOOL_CONFIG_VERSION, version) != 0)
 540                                         goto nomem;
 541                                 verify(nvlist_lookup_uint64(tmp,
 542                                     ZPOOL_CONFIG_POOL_GUID, &guid) == 0);
 543                                 if (nvlist_add_uint64(config,
 544                                     ZPOOL_CONFIG_POOL_GUID, guid) != 0)
 545                                         goto nomem;
 546                                 verify(nvlist_lookup_string(tmp,
 547                                     ZPOOL_CONFIG_POOL_NAME, &name) == 0);
 548                                 if (nvlist_add_string(config,
 549                                     ZPOOL_CONFIG_POOL_NAME, name) != 0)
 550                                         goto nomem;
 551                                 verify(nvlist_lookup_uint64(tmp,
 552                                     ZPOOL_CONFIG_POOL_STATE, &state) == 0);
 553                                 if (nvlist_add_uint64(config,
 554                                     ZPOOL_CONFIG_POOL_STATE, state) != 0)
 555                                         goto nomem;
 556                                 hostid = 0;
 557                                 if (nvlist_lookup_uint64(tmp,
 558                                     ZPOOL_CONFIG_HOSTID, &hostid) == 0) {
 559                                         if (nvlist_add_uint64(config,
 560                                             ZPOOL_CONFIG_HOSTID, hostid) != 0)
 561                                                 goto nomem;
 562                                         verify(nvlist_lookup_string(tmp,
 563                                             ZPOOL_CONFIG_HOSTNAME,
 564                                             &hostname) == 0);
 565                                         if (nvlist_add_string(config,
 566                                             ZPOOL_CONFIG_HOSTNAME,
 567                                             hostname) != 0)
 568                                                 goto nomem;
 569                                 }
 570
 571                                 config_seen = B_TRUE;
 572                         }
 573
 574                         /*
 575                          * Add this top-level vdev to the child array.
 576                          */
 577                         verify(nvlist_lookup_nvlist(tmp,
 578                             ZPOOL_CONFIG_VDEV_TREE, &nvtop) == 0);
 579                         verify(nvlist_lookup_uint64(nvtop, ZPOOL_CONFIG_ID,
 580                             &id) == 0);
 581
 582                         if (id >= children) {
 583                                 nvlist_t **newchild;
 584
 585                                 newchild = zfs_alloc(hdl, (id + 1) *
 586                                     sizeof (nvlist_t *));
 587                                 if (newchild == NULL)
 588                                         goto nomem;
 589
 590                                 for (c = 0; c < children; c++)
 591                                         newchild[c] = child[c];
 592
 593                                 free(child);
 594                                 child = newchild;
 595                                 children = id + 1;
 596                         }
 597                         if (nvlist_dup(nvtop, &child[id], 0) != 0)
 598                                 goto nomem;
 599
 600                 }
 601
 602                 /*
 603                  * If we have information about all the top-levels then
 604                  * clean up the nvlist which we've constructed. This
 605                  * means removing any extraneous devices that are
 606                  * beyond the valid range or adding devices to the end
 607                  * of our array which appear to be missing.
 608                  */
 609                 if (valid_top_config) {
 610                         if (max_id < children) {
 611                                 for (c = max_id; c < children; c++)
 612                                         nvlist_free(child[c]);
 613                                 children = max_id;
 614                         } else if (max_id > children) {
 615                                 nvlist_t **newchild;
 616
 617                                 newchild = zfs_alloc(hdl, (max_id) *
 618                                     sizeof (nvlist_t *));
 619                                 if (newchild == NULL)
 620                                         goto nomem;
 621
 622                                 for (c = 0; c < children; c++)
 623                                         newchild[c] = child[c];
 624
 625                                 free(child);
 626                                 child = newchild;
 627                                 children = max_id;
 628                         }
 629                 }
 630
 631                 verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
 632                     &guid) == 0);
 633
 634                 /*
 635                  * The vdev namespace may contain holes as a result of
 636                  * device removal. We must add them back into the vdev
 637                  * tree before we process any missing devices.
 638                  */
 639                 if (holes > 0) {
 640                         ASSERT(valid_top_config);
 641
 642                         for (c = 0; c < children; c++) {
 643                                 nvlist_t *holey;
 644
 645                                 if (child[c] != NULL ||
 646                                     !vdev_is_hole(hole_array, holes, c))
 647                                         continue;
 648
 649                                 if (nvlist_alloc(&holey, NV_UNIQUE_NAME,
 650                                     0) != 0)
 651                                         goto nomem;
 652
 653                                 /*
 654                                  * Holes in the namespace are treated as
 655                                  * "hole" top-level vdevs and have a
 656                                  * special flag set on them.
 657                                  */
 658                                 if (nvlist_add_string(holey,
 659                                     ZPOOL_CONFIG_TYPE,
 660                                     VDEV_TYPE_HOLE) != 0 ||
 661                                     nvlist_add_uint64(holey,
 662                                     ZPOOL_CONFIG_ID, c) != 0 ||
 663                                     nvlist_add_uint64(holey,
 664                                     ZPOOL_CONFIG_GUID, 0ULL) != 0)
 665                                         goto nomem;
 666                                 child[c] = holey;
 667                         }
 668                 }
 669
 670                 /*
 671                  * Look for any missing top-level vdevs.  If this is the case,
 672                  * create a faked up 'missing' vdev as a placeholder.  We cannot
 673                  * simply compress the child array, because the kernel performs
 674                  * certain checks to make sure the vdev IDs match their location
 675                  * in the configuration.
 676                  */
 677                 for (c = 0; c < children; c++) {
 678                         if (child[c] == NULL) {
 679                                 nvlist_t *missing;
 680                                 if (nvlist_alloc(&missing, NV_UNIQUE_NAME,
 681                                     0) != 0)
 682                                         goto nomem;
 683                                 if (nvlist_add_string(missing,
 684                                     ZPOOL_CONFIG_TYPE,
 685                                     VDEV_TYPE_MISSING) != 0 ||
 686                                     nvlist_add_uint64(missing,
 687                                     ZPOOL_CONFIG_ID, c) != 0 ||
 688                                     nvlist_add_uint64(missing,
 689                                     ZPOOL_CONFIG_GUID, 0ULL) != 0) {
 690                                         nvlist_free(missing);
 691                                         goto nomem;
 692                                 }
 693                                 child[c] = missing;
 694                         }
 695                 }
 696
 697                 /*
 698                  * Put all of this pool's top-level vdevs into a root vdev.
 699                  */
 700                 if (nvlist_alloc(&nvroot, NV_UNIQUE_NAME, 0) != 0)
 701                         goto nomem;
 702                 if (nvlist_add_string(nvroot, ZPOOL_CONFIG_TYPE,
 703                     VDEV_TYPE_ROOT) != 0 ||
 704                     nvlist_add_uint64(nvroot, ZPOOL_CONFIG_ID, 0ULL) != 0 ||
 705                     nvlist_add_uint64(nvroot, ZPOOL_CONFIG_GUID, guid) != 0 ||
 706                     nvlist_add_nvlist_array(nvroot, ZPOOL_CONFIG_CHILDREN,
 707                     child, children) != 0) {
 708                         nvlist_free(nvroot);
 709                         goto nomem;
 710                 }
 711
 712                 for (c = 0; c < children; c++)
 713                         nvlist_free(child[c]);
 714                 free(child);
 715                 children = 0;
 716                 child = NULL;
 717
 718                 /*
 719                  * Go through and fix up any paths and/or devids based on our
 720                  * known list of vdev GUID -> path mappings.
 721                  */
 722                 if (fix_paths(nvroot, pl->names) != 0) {
 723                         nvlist_free(nvroot);
 724                         goto nomem;
 725                 }
 726
 727                 /*
 728                  * Add the root vdev to this pool's configuration.
 729                  */
 730                 if (nvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
 731                     nvroot) != 0) {
 732                         nvlist_free(nvroot);
 733                         goto nomem;
 734                 }
 735                 nvlist_free(nvroot);
 736
 737                 /*
 738                  * zdb uses this path to report on active pools that were
 739                  * imported or created using -R.
 740                  */
 741                 if (active_ok)
 742                         goto add_pool;
 743
 744                 /*
 745                  * Determine if this pool is currently active, in which case we
 746                  * can't actually import it.
 747                  */
 748                 verify(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
 749                     &name) == 0);
 750                 verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
 751                     &guid) == 0);
 752
 753                 if (pool_active(hdl, name, guid, &isactive) != 0)
 754                         goto error;
 755
 756                 if (isactive) {
 757                         nvlist_free(config);
 758                         config = NULL;
 759                         continue;
 760                 }
 761
 762                 if ((nvl = refresh_config(hdl, config)) == NULL) {
 763                         nvlist_free(config);
 764                         config = NULL;
 765                         continue;
 766                 }
 767
 768                 nvlist_free(config);
 769                 config = nvl;
 770
 771                 /*
 772                  * Go through and update the paths for spares, now that we have
 773                  * them.
 774                  */
 775                 verify(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
 776                     &nvroot) == 0);
 777                 if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES,
 778                     &spares, &nspares) == 0) {
 779                         for (i = 0; i < nspares; i++) {
 780                                 if (fix_paths(spares[i], pl->names) != 0)
 781                                         goto nomem;
 782                         }
 783                 }
 784
 785                 /*
 786                  * Update the paths for l2cache devices.
 787                  */
 788                 if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_L2CACHE,
 789                     &l2cache, &nl2cache) == 0) {
 790                         for (i = 0; i < nl2cache; i++) {
 791                                 if (fix_paths(l2cache[i], pl->names) != 0)
 792                                         goto nomem;
 793                         }
 794                 }
 795
 796                 /*
 797                  * Restore the original information read from the actual label.
 798                  */
 799                 (void) nvlist_remove(config, ZPOOL_CONFIG_HOSTID,
 800                     DATA_TYPE_UINT64);
 801                 (void) nvlist_remove(config, ZPOOL_CONFIG_HOSTNAME,
 802                     DATA_TYPE_STRING);
 803                 if (hostid != 0) {
 804                         verify(nvlist_add_uint64(config, ZPOOL_CONFIG_HOSTID,
 805                             hostid) == 0);
 806                         verify(nvlist_add_string(config, ZPOOL_CONFIG_HOSTNAME,
 807                             hostname) == 0);
 808                 }
 809
 810 add_pool:
 811                 /*
 812                  * Add this pool to the list of configs.
 813                  */
 814                 verify(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
 815                     &name) == 0);
 816                 if (nvlist_add_nvlist(ret, name, config) != 0)
 817                         goto nomem;
 818
 819                 found_one = B_TRUE;
 820                 nvlist_free(config);
 821                 config = NULL;
 822         }
 823
 824         if (!found_one) {
 825                 nvlist_free(ret);
 826                 ret = NULL;
 827         }
 828
 829         return (ret);
 830
 831 nomem:
 832         (void) no_memory(hdl);
 833 error:
 834         nvlist_free(config);
 835         nvlist_free(ret);
 836         for (c = 0; c < children; c++)
 837                 nvlist_free(child[c]);
 838         free(child);
 839
 840         return (NULL);
 841 }
 842
 843 /*
 844  * Return the offset of the given label.
 845  */
 846 static uint64_t
 847 label_offset(uint64_t size, int l)
 848 {
 849         ASSERT(P2PHASE_TYPED(size, sizeof (vdev_label_t), uint64_t) == 0);
 850         return (l * sizeof (vdev_label_t) + (l < VDEV_LABELS / 2 ?
 851             0 : size - VDEV_LABELS * sizeof (vdev_label_t)));
 852 }
 853
 854 /*
 855  * Given a file descriptor, read the label information and return an nvlist
 856  * describing the configuration, if there is one.
 857  */
 858 int
 859 zpool_read_label(int fd, nvlist_t **config)
 860 {
 861         struct stat64 statbuf;
 862         int l;
 863         vdev_label_t *label;
 864         uint64_t state, txg, size;
 865
 866         *config = NULL;
 867
 868         if (fstat64(fd, &statbuf) == -1)
 869                 return (0);
 870         size = P2ALIGN_TYPED(statbuf.st_size, sizeof (vdev_label_t), uint64_t);
 871
 872         if ((label = malloc(sizeof (vdev_label_t))) == NULL)
 873                 return (-1);
 874
 875         for (l = 0; l < VDEV_LABELS; l++) {
 876                 if (pread64(fd, label, sizeof (vdev_label_t),
 877                     label_offset(size, l)) != sizeof (vdev_label_t))
 878                         continue;
 879
 880                 if (nvlist_unpack(label->vl_vdev_phys.vp_nvlist,
 881                     sizeof (label->vl_vdev_phys.vp_nvlist), config, 0) != 0)
 882                         continue;
 883
 884                 if (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_STATE,
 885                     &state) != 0 || state > POOL_STATE_L2CACHE) {
 886                         nvlist_free(*config);
 887                         continue;
 888                 }
 889
 890                 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE &&
 891                     (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_TXG,
 892                     &txg) != 0 || txg == 0)) {
 893                         nvlist_free(*config);
 894                         continue;
 895                 }
 896
 897                 free(label);
 898                 return (0);
 899         }
 900
 901         free(label);
 902         *config = NULL;
 903         return (0);
 904 }
 905
 906 typedef struct rdsk_node {
 907         char *rn_name;
 908         int rn_dfd;
 909         libzfs_handle_t *rn_hdl;
 910         nvlist_t *rn_config;
 911         avl_tree_t *rn_avl;
 912         avl_node_t rn_node;
 913         boolean_t rn_nozpool;
 914 } rdsk_node_t;
 915
 916 static int
 917 slice_cache_compare(const void *arg1, const void *arg2)
 918 {
 919         const char  *nm1 = ((rdsk_node_t *)arg1)->rn_name;
 920         const char  *nm2 = ((rdsk_node_t *)arg2)->rn_name;
 921         char *nm1slice, *nm2slice;
 922         int rv;
 923
 924         /*
 925          * slices zero and two are the most likely to provide results,
 926          * so put those first
 927          */
 928         nm1slice = strstr(nm1, "s0");
 929         nm2slice = strstr(nm2, "s0");
 930         if (nm1slice && !nm2slice) {
 931                 return (-1);
 932         }
 933         if (!nm1slice && nm2slice) {
 934                 return (1);
 935         }
 936         nm1slice = strstr(nm1, "s2");
 937         nm2slice = strstr(nm2, "s2");
 938         if (nm1slice && !nm2slice) {
 939                 return (-1);
 940         }
 941         if (!nm1slice && nm2slice) {
 942                 return (1);
 943         }
 944
 945         rv = strcmp(nm1, nm2);
 946         if (rv == 0)
 947                 return (0);
 948         return (rv > 0 ? 1 : -1);
 949 }
 950
 951 static void
 952 check_one_slice(avl_tree_t *r, char *diskname, uint_t partno,
 953     diskaddr_t size, uint_t blksz)
 954 {
 955         rdsk_node_t tmpnode;
 956         rdsk_node_t *node;
 957         char sname[MAXNAMELEN];
 958
 959         tmpnode.rn_name = &sname[0];
 960         (void) snprintf(tmpnode.rn_name, MAXNAMELEN, "%s%u",
 961             diskname, partno);
 962         /*
 963          * protect against division by zero for disk labels that
 964          * contain a bogus sector size
 965          */
 966         if (blksz == 0)
 967                 blksz = DEV_BSIZE;
 968         /* too small to contain a zpool? */
 969         if ((size < (SPA_MINDEVSIZE / blksz)) &&
 970             (node = avl_find(r, &tmpnode, NULL)))
 971                 node->rn_nozpool = B_TRUE;
 972 }
 973
 974 static void
 975 nozpool_all_slices(avl_tree_t *r, const char *sname)
 976 {
 977         char diskname[MAXNAMELEN];
 978         char *ptr;
 979         int i;
 980
 981         (void) strncpy(diskname, sname, MAXNAMELEN);
 982         if (((ptr = strrchr(diskname, 's')) == NULL) &&
 983             ((ptr = strrchr(diskname, 'p')) == NULL))
 984                 return;
 985         ptr[0] = 's';
 986         ptr[1] = '\0';
 987         for (i = 0; i < NDKMAP; i++)
 988                 check_one_slice(r, diskname, i, 0, 1);
 989         ptr[0] = 'p';
 990         for (i = 0; i <= FD_NUMPART; i++)
 991                 check_one_slice(r, diskname, i, 0, 1);
 992 }
 993
 994 static void
 995 check_slices(avl_tree_t *r, int fd, const char *sname)
 996 {
 997         struct extvtoc vtoc;
 998         struct dk_gpt *gpt;
 999         char diskname[MAXNAMELEN];
1000         char *ptr;
1001         int i;
1002
1003         (void) strncpy(diskname, sname, MAXNAMELEN);
1004         if ((ptr = strrchr(diskname, 's')) == NULL || !isdigit(ptr[1]))
1005                 return;
1006         ptr[1] = '\0';
1007
1008         if (read_extvtoc(fd, &vtoc) >= 0) {
1009                 for (i = 0; i < NDKMAP; i++)
1010                         check_one_slice(r, diskname, i,
1011                             vtoc.v_part[i].p_size, vtoc.v_sectorsz);
1012         } else if (efi_alloc_and_read(fd, &gpt) >= 0) {
1013                 /*
1014                  * on x86 we'll still have leftover links that point
1015                  * to slices s[9-15], so use NDKMAP instead
1016                  */
1017                 for (i = 0; i < NDKMAP; i++)
1018                         check_one_slice(r, diskname, i,
1019                             gpt->efi_parts[i].p_size, gpt->efi_lbasize);
1020                 /* nodes p[1-4] are never used with EFI labels */
1021                 ptr[0] = 'p';
1022                 for (i = 1; i <= FD_NUMPART; i++)
1023                         check_one_slice(r, diskname, i, 0, 1);
1024                 efi_free(gpt);
1025         }
1026 }
1027
1028 static void
1029 zpool_open_func(void *arg)
1030 {
1031         rdsk_node_t *rn = arg;
1032         struct stat64 statbuf;
1033         nvlist_t *config;
1034         int fd;
1035
1036         if (rn->rn_nozpool)
1037                 return;
1038         if ((fd = openat64(rn->rn_dfd, rn->rn_name, O_RDONLY)) < 0) {
1039                 /* symlink to a device that's no longer there */
1040                 if (errno == ENOENT)
1041                         nozpool_all_slices(rn->rn_avl, rn->rn_name);
1042                 return;
1043         }
1044         /*
1045          * Ignore failed stats.  We only want regular
1046          * files, character devs and block devs.
1047          */
1048         if (fstat64(fd, &statbuf) != 0 ||
1049             (!S_ISREG(statbuf.st_mode) &&
1050             !S_ISCHR(statbuf.st_mode) &&
1051             !S_ISBLK(statbuf.st_mode))) {
1052                 (void) close(fd);
1053                 return;
1054         }
1055         /* this file is too small to hold a zpool */
1056         if (S_ISREG(statbuf.st_mode) &&
1057             statbuf.st_size < SPA_MINDEVSIZE) {
1058                 (void) close(fd);
1059                 return;
1060         } else if (!S_ISREG(statbuf.st_mode)) {
1061                 /*
1062                  * Try to read the disk label first so we don't have to
1063                  * open a bunch of minor nodes that can't have a zpool.
1064                  */
1065                 check_slices(rn->rn_avl, fd, rn->rn_name);
1066         }
1067
1068         if ((zpool_read_label(fd, &config)) != 0) {
1069                 (void) close(fd);
1070                 (void) no_memory(rn->rn_hdl);
1071                 return;
1072         }
1073         (void) close(fd);
1074
1075
1076         rn->rn_config = config;
1077         if (config != NULL) {
1078                 assert(rn->rn_nozpool == B_FALSE);
1079         }
1080 }
1081
1082 /*
1083  * Given a file descriptor, clear (zero) the label information.  This function
1084  * is currently only used in the appliance stack as part of the ZFS sysevent
1085  * module.
1086  */
1087 int
1088 zpool_clear_label(int fd)
1089 {
1090         struct stat64 statbuf;
1091         int l;
1092         vdev_label_t *label;
1093         uint64_t size;
1094
1095         if (fstat64(fd, &statbuf) == -1)
1096                 return (0);
1097         size = P2ALIGN_TYPED(statbuf.st_size, sizeof (vdev_label_t), uint64_t);
1098
1099         if ((label = calloc(sizeof (vdev_label_t), 1)) == NULL)
1100                 return (-1);
1101
1102         for (l = 0; l < VDEV_LABELS; l++) {
1103                 if (pwrite64(fd, label, sizeof (vdev_label_t),
1104                     label_offset(size, l)) != sizeof (vdev_label_t))
1105                         return (-1);
1106         }
1107
1108         free(label);
1109         return (0);
1110 }
1111
1112 /*
1113  * Given a list of directories to search, find all pools stored on disk.  This
1114  * includes partial pools which are not available to import.  If no args are
1115  * given (argc is 0), then the default directory (/dev/dsk) is searched.
1116  * poolname or guid (but not both) are provided by the caller when trying
1117  * to import a specific pool.
1118  */
1119 static nvlist_t *
1120 zpool_find_import_impl(libzfs_handle_t *hdl, importargs_t *iarg)
1121 {
1122         int i, dirs = iarg->paths;
1123         DIR *dirp = NULL;
1124         struct dirent64 *dp;
1125         char path[MAXPATHLEN];
1126         char *end, **dir = iarg->path;
1127         size_t pathleft;
1128         nvlist_t *ret = NULL;
1129         static char *default_dir = "/dev/dsk";
1130         pool_list_t pools = { 0 };
1131         pool_entry_t *pe, *penext;
1132         vdev_entry_t *ve, *venext;
1133         config_entry_t *ce, *cenext;
1134         name_entry_t *ne, *nenext;
1135         avl_tree_t slice_cache;
1136         rdsk_node_t *slice;
1137         void *cookie;
1138
1139         if (dirs == 0) {
1140                 dirs = 1;
1141                 dir = &default_dir;
1142         }
1143
1144         /*
1145          * Go through and read the label configuration information from every
1146          * possible device, organizing the information according to pool GUID
1147          * and toplevel GUID.
1148          */
1149         for (i = 0; i < dirs; i++) {
1150                 tpool_t *t;
1151                 char *rdsk;
1152                 int dfd;
1153
1154                 /* use realpath to normalize the path */
1155                 if (realpath(dir[i], path) == 0) {
1156                         (void) zfs_error_fmt(hdl, EZFS_BADPATH,
1157                             dgettext(TEXT_DOMAIN, "cannot open '%s'"), dir[i]);
1158                         goto error;
1159                 }
1160                 end = &path[strlen(path)];
1161                 *end++ = '/';
1162                 *end = 0;
1163                 pathleft = &path[sizeof (path)] - end;
1164
1165                 /*
1166                  * Using raw devices instead of block devices when we're
1167                  * reading the labels skips a bunch of slow operations during
1168                  * close(2) processing, so we replace /dev/dsk with /dev/rdsk.
1169                  */
1170                 if (strcmp(path, "/dev/dsk/") == 0)
1171                         rdsk = "/dev/rdsk/";
1172                 else
1173                         rdsk = path;
1174
1175                 if ((dfd = open64(rdsk, O_RDONLY)) < 0 ||
1176                     (dirp = fdopendir(dfd)) == NULL) {
1177                         zfs_error_aux(hdl, strerror(errno));
1178                         (void) zfs_error_fmt(hdl, EZFS_BADPATH,
1179                             dgettext(TEXT_DOMAIN, "cannot open '%s'"),
1180                             rdsk);
1181                         goto error;
1182                 }
1183
1184                 avl_create(&slice_cache, slice_cache_compare,
1185                     sizeof (rdsk_node_t), offsetof(rdsk_node_t, rn_node));
1186                 /*
1187                  * This is not MT-safe, but we have no MT consumers of libzfs
1188                  */
1189                 while ((dp = readdir64(dirp)) != NULL) {
1190                         const char *name = dp->d_name;
1191                         if (name[0] == '.' &&
1192                             (name[1] == 0 || (name[1] == '.' && name[2] == 0)))
1193                                 continue;
1194
1195                         slice = zfs_alloc(hdl, sizeof (rdsk_node_t));
1196                         slice->rn_name = zfs_strdup(hdl, name);
1197                         slice->rn_avl = &slice_cache;
1198                         slice->rn_dfd = dfd;
1199                         slice->rn_hdl = hdl;
1200                         slice->rn_nozpool = B_FALSE;
1201                         avl_add(&slice_cache, slice);
1202                 }
1203                 /*
1204                  * create a thread pool to do all of this in parallel;
1205                  * rn_nozpool is not protected, so this is racy in that
1206                  * multiple tasks could decide that the same slice can
1207                  * not hold a zpool, which is benign.  Also choose
1208                  * double the number of processors; we hold a lot of
1209                  * locks in the kernel, so going beyond this doesn't
1210                  * buy us much.
1211                  */
1212                 t = tpool_create(1, 2 * sysconf(_SC_NPROCESSORS_ONLN),
1213                     0, NULL);
1214                 for (slice = avl_first(&slice_cache); slice;
1215                     (slice = avl_walk(&slice_cache, slice,
1216                     AVL_AFTER)))
1217                         (void) tpool_dispatch(t, zpool_open_func, slice);
1218                 tpool_wait(t);
1219                 tpool_destroy(t);
1220
1221                 cookie = NULL;
1222                 while ((slice = avl_destroy_nodes(&slice_cache,
1223                     &cookie)) != NULL) {
1224                         if (slice->rn_config != NULL) {
1225                                 nvlist_t *config = slice->rn_config;
1226                                 boolean_t matched = B_TRUE;
1227
1228                                 if (iarg->poolname != NULL) {
1229                                         char *pname;
1230
1231                                         matched = nvlist_lookup_string(config,
1232                                             ZPOOL_CONFIG_POOL_NAME,
1233                                             &pname) == 0 &&
1234                                             strcmp(iarg->poolname, pname) == 0;
1235                                 } else if (iarg->guid != 0) {
1236                                         uint64_t this_guid;
1237
1238                                         matched = nvlist_lookup_uint64(config,
1239                                             ZPOOL_CONFIG_POOL_GUID,
1240                                             &this_guid) == 0 &&
1241                                             iarg->guid == this_guid;
1242                                 }
1243                                 if (!matched) {
1244                                         nvlist_free(config);
1245                                         config = NULL;
1246                                         continue;
1247                                 }
1248                                 /* use the non-raw path for the config */
1249                                 (void) strlcpy(end, slice->rn_name, pathleft);
1250                                 if (add_config(hdl, &pools, path, config) != 0)
1251                                         goto error;
1252                         }
1253                         free(slice->rn_name);
1254                         free(slice);
1255                 }
1256                 avl_destroy(&slice_cache);
1257
1258                 (void) closedir(dirp);
1259                 dirp = NULL;
1260         }
1261
1262         ret = get_configs(hdl, &pools, iarg->can_be_active);
1263
1264 error:
1265         for (pe = pools.pools; pe != NULL; pe = penext) {
1266                 penext = pe->pe_next;
1267                 for (ve = pe->pe_vdevs; ve != NULL; ve = venext) {
1268                         venext = ve->ve_next;
1269                         for (ce = ve->ve_configs; ce != NULL; ce = cenext) {
1270                                 cenext = ce->ce_next;
1271                                 if (ce->ce_config)
1272                                         nvlist_free(ce->ce_config);
1273                                 free(ce);
1274                         }
1275                         free(ve);
1276                 }
1277                 free(pe);
1278         }
1279
1280         for (ne = pools.names; ne != NULL; ne = nenext) {
1281                 nenext = ne->ne_next;
1282                 if (ne->ne_name)
1283                         free(ne->ne_name);
1284                 free(ne);
1285         }
1286
1287         if (dirp)
1288                 (void) closedir(dirp);
1289
1290         return (ret);
1291 }
1292
1293 nvlist_t *
1294 zpool_find_import(libzfs_handle_t *hdl, int argc, char **argv)
1295 {
1296         importargs_t iarg = { 0 };
1297
1298         iarg.paths = argc;
1299         iarg.path = argv;
1300
1301         return (zpool_find_import_impl(hdl, &iarg));
1302 }
1303
1304 /*
1305  * Given a cache file, return the contents as a list of importable pools.
1306  * poolname or guid (but not both) are provided by the caller when trying
1307  * to import a specific pool.
1308  */
1309 nvlist_t *
1310 zpool_find_import_cached(libzfs_handle_t *hdl, const char *cachefile,
1311     char *poolname, uint64_t guid)
1312 {
1313         char *buf;
1314         int fd;
1315         struct stat64 statbuf;
1316         nvlist_t *raw, *src, *dst;
1317         nvlist_t *pools;
1318         nvpair_t *elem;
1319         char *name;
1320         uint64_t this_guid;
1321         boolean_t active;
1322
1323         verify(poolname == NULL || guid == 0);
1324
1325         if ((fd = open(cachefile, O_RDONLY)) < 0) {
1326                 zfs_error_aux(hdl, "%s", strerror(errno));
1327                 (void) zfs_error(hdl, EZFS_BADCACHE,
1328                     dgettext(TEXT_DOMAIN, "failed to open cache file"));
1329                 return (NULL);
1330         }
1331
1332         if (fstat64(fd, &statbuf) != 0) {
1333                 zfs_error_aux(hdl, "%s", strerror(errno));
1334                 (void) close(fd);
1335                 (void) zfs_error(hdl, EZFS_BADCACHE,
1336                     dgettext(TEXT_DOMAIN, "failed to get size of cache file"));
1337                 return (NULL);
1338         }
1339
1340         if ((buf = zfs_alloc(hdl, statbuf.st_size)) == NULL) {
1341                 (void) close(fd);
1342                 return (NULL);
1343         }
1344
1345         if (read(fd, buf, statbuf.st_size) != statbuf.st_size) {
1346                 (void) close(fd);
1347                 free(buf);
1348                 (void) zfs_error(hdl, EZFS_BADCACHE,
1349                     dgettext(TEXT_DOMAIN,
1350                     "failed to read cache file contents"));
1351                 return (NULL);
1352         }
1353
1354         (void) close(fd);
1355
1356         if (nvlist_unpack(buf, statbuf.st_size, &raw, 0) != 0) {
1357                 free(buf);
1358                 (void) zfs_error(hdl, EZFS_BADCACHE,
1359                     dgettext(TEXT_DOMAIN,
1360                     "invalid or corrupt cache file contents"));
1361                 return (NULL);
1362         }
1363
1364         free(buf);
1365
1366         /*
1367          * Go through and get the current state of the pools and refresh their
1368          * state.
1369          */
1370         if (nvlist_alloc(&pools, 0, 0) != 0) {
1371                 (void) no_memory(hdl);
1372                 nvlist_free(raw);
1373                 return (NULL);
1374         }
1375
1376         elem = NULL;
1377         while ((elem = nvlist_next_nvpair(raw, elem)) != NULL) {
1378                 verify(nvpair_value_nvlist(elem, &src) == 0);
1379
1380                 verify(nvlist_lookup_string(src, ZPOOL_CONFIG_POOL_NAME,
1381                     &name) == 0);
1382                 if (poolname != NULL && strcmp(poolname, name) != 0)
1383                         continue;
1384
1385                 verify(nvlist_lookup_uint64(src, ZPOOL_CONFIG_POOL_GUID,
1386                     &this_guid) == 0);
1387                 if (guid != 0) {
1388                         verify(nvlist_lookup_uint64(src, ZPOOL_CONFIG_POOL_GUID,
1389                             &this_guid) == 0);
1390                         if (guid != this_guid)
1391                                 continue;
1392                 }
1393
1394                 if (pool_active(hdl, name, this_guid, &active) != 0) {
1395                         nvlist_free(raw);
1396                         nvlist_free(pools);
1397                         return (NULL);
1398                 }
1399
1400                 if (active)
1401                         continue;
1402
1403                 if ((dst = refresh_config(hdl, src)) == NULL) {
1404                         nvlist_free(raw);
1405                         nvlist_free(pools);
1406                         return (NULL);
1407                 }
1408
1409                 if (nvlist_add_nvlist(pools, nvpair_name(elem), dst) != 0) {
1410                         (void) no_memory(hdl);
1411                         nvlist_free(dst);
1412                         nvlist_free(raw);
1413                         nvlist_free(pools);
1414                         return (NULL);
1415                 }
1416                 nvlist_free(dst);
1417         }
1418
1419         nvlist_free(raw);
1420         return (pools);
1421 }
1422
1423 static int
1424 name_or_guid_exists(zpool_handle_t *zhp, void *data)
1425 {
1426         importargs_t *import = data;
1427         int found = 0;
1428
1429         if (import->poolname != NULL) {
1430                 char *pool_name;
1431
1432                 verify(nvlist_lookup_string(zhp->zpool_config,
1433                     ZPOOL_CONFIG_POOL_NAME, &pool_name) == 0);
1434                 if (strcmp(pool_name, import->poolname) == 0)
1435                         found = 1;
1436         } else {
1437                 uint64_t pool_guid;
1438
1439                 verify(nvlist_lookup_uint64(zhp->zpool_config,
1440                     ZPOOL_CONFIG_POOL_GUID, &pool_guid) == 0);
1441                 if (pool_guid == import->guid)
1442                         found = 1;
1443         }
1444
1445         zpool_close(zhp);
1446         return (found);
1447 }
1448
1449 nvlist_t *
1450 zpool_search_import(libzfs_handle_t *hdl, importargs_t *import)
1451 {
1452         verify(import->poolname == NULL || import->guid == 0);
1453
1454         if (import->unique)
1455                 import->exists = zpool_iter(hdl, name_or_guid_exists, import);
1456
1457         if (import->cachefile != NULL)
1458                 return (zpool_find_import_cached(hdl, import->cachefile,
1459                     import->poolname, import->guid));
1460
1461         return (zpool_find_import_impl(hdl, import));
1462 }
1463
1464 boolean_t
1465 find_guid(nvlist_t *nv, uint64_t guid)
1466 {
1467         uint64_t tmp;
1468         nvlist_t **child;
1469         uint_t c, children;
1470
1471         verify(nvlist_lookup_uint64(nv, ZPOOL_CONFIG_GUID, &tmp) == 0);
1472         if (tmp == guid)
1473                 return (B_TRUE);
1474
1475         if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
1476             &child, &children) == 0) {
1477                 for (c = 0; c < children; c++)
1478                         if (find_guid(child[c], guid))
1479                                 return (B_TRUE);
1480         }
1481
1482         return (B_FALSE);
1483 }
1484
1485 typedef struct aux_cbdata {
1486         const char      *cb_type;
1487         uint64_t        cb_guid;
1488         zpool_handle_t  *cb_zhp;
1489 } aux_cbdata_t;
1490
1491 static int
1492 find_aux(zpool_handle_t *zhp, void *data)
1493 {
1494         aux_cbdata_t *cbp = data;
1495         nvlist_t **list;
1496         uint_t i, count;
1497         uint64_t guid;
1498         nvlist_t *nvroot;
1499
1500         verify(nvlist_lookup_nvlist(zhp->zpool_config, ZPOOL_CONFIG_VDEV_TREE,
1501             &nvroot) == 0);
1502
1503         if (nvlist_lookup_nvlist_array(nvroot, cbp->cb_type,
1504             &list, &count) == 0) {
1505                 for (i = 0; i < count; i++) {
1506                         verify(nvlist_lookup_uint64(list[i],
1507                             ZPOOL_CONFIG_GUID, &guid) == 0);
1508                         if (guid == cbp->cb_guid) {
1509                                 cbp->cb_zhp = zhp;
1510                                 return (1);
1511                         }
1512                 }
1513         }
1514
1515         zpool_close(zhp);
1516         return (0);
1517 }
1518
1519 /*
1520  * Determines if the pool is in use.  If so, it returns true and the state of
1521  * the pool as well as the name of the pool.  Both strings are allocated and
1522  * must be freed by the caller.
1523  */
1524 int
1525 zpool_in_use(libzfs_handle_t *hdl, int fd, pool_state_t *state, char **namestr,
1526     boolean_t *inuse)
1527 {
1528         nvlist_t *config;
1529         char *name;
1530         boolean_t ret;
1531         uint64_t guid, vdev_guid;
1532         zpool_handle_t *zhp;
1533         nvlist_t *pool_config;
1534         uint64_t stateval, isspare;
1535         aux_cbdata_t cb = { 0 };
1536         boolean_t isactive;
1537
1538         *inuse = B_FALSE;
1539
1540         if (zpool_read_label(fd, &config) != 0) {
1541                 (void) no_memory(hdl);
1542                 return (-1);
1543         }
1544
1545         if (config == NULL)
1546                 return (0);
1547
1548         verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_STATE,
1549             &stateval) == 0);
1550         verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID,
1551             &vdev_guid) == 0);
1552
1553         if (stateval != POOL_STATE_SPARE && stateval != POOL_STATE_L2CACHE) {
1554                 verify(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
1555                     &name) == 0);
1556                 verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
1557                     &guid) == 0);
1558         }
1559
1560         switch (stateval) {
1561         case POOL_STATE_EXPORTED:
1562                 ret = B_TRUE;
1563                 break;
1564
1565         case POOL_STATE_ACTIVE:
1566                 /*
1567                  * For an active pool, we have to determine if it's really part
1568                  * of a currently active pool (in which case the pool will exist
1569                  * and the guid will be the same), or whether it's part of an
1570                  * active pool that was disconnected without being explicitly
1571                  * exported.
1572                  */
1573                 if (pool_active(hdl, name, guid, &isactive) != 0) {
1574                         nvlist_free(config);
1575                         return (-1);
1576                 }
1577
1578                 if (isactive) {
1579                         /*
1580                          * Because the device may have been removed while
1581                          * offlined, we only report it as active if the vdev is
1582                          * still present in the config.  Otherwise, pretend like
1583                          * it's not in use.
1584                          */
1585                         if ((zhp = zpool_open_canfail(hdl, name)) != NULL &&
1586                             (pool_config = zpool_get_config(zhp, NULL))
1587                             != NULL) {
1588                                 nvlist_t *nvroot;
1589
1590                                 verify(nvlist_lookup_nvlist(pool_config,
1591                                     ZPOOL_CONFIG_VDEV_TREE, &nvroot) == 0);
1592                                 ret = find_guid(nvroot, vdev_guid);
1593                         } else {
1594                                 ret = B_FALSE;
1595                         }
1596
1597                         /*
1598                          * If this is an active spare within another pool, we
1599                          * treat it like an unused hot spare.  This allows the
1600                          * user to create a pool with a hot spare that currently
1601                          * in use within another pool.  Since we return B_TRUE,
1602                          * libdiskmgt will continue to prevent generic consumers
1603                          * from using the device.
1604                          */
1605                         if (ret && nvlist_lookup_uint64(config,
1606                             ZPOOL_CONFIG_IS_SPARE, &isspare) == 0 && isspare)
1607                                 stateval = POOL_STATE_SPARE;
1608
1609                         if (zhp != NULL)
1610                                 zpool_close(zhp);
1611                 } else {
1612                         stateval = POOL_STATE_POTENTIALLY_ACTIVE;
1613                         ret = B_TRUE;
1614                 }
1615                 break;
1616
1617         case POOL_STATE_SPARE:
1618                 /*
1619                  * For a hot spare, it can be either definitively in use, or
1620                  * potentially active.  To determine if it's in use, we iterate
1621                  * over all pools in the system and search for one with a spare
1622                  * with a matching guid.
1623                  *
1624                  * Due to the shared nature of spares, we don't actually report
1625                  * the potentially active case as in use.  This means the user
1626                  * can freely create pools on the hot spares of exported pools,
1627                  * but to do otherwise makes the resulting code complicated, and
1628                  * we end up having to deal with this case anyway.
1629                  */
1630                 cb.cb_zhp = NULL;
1631                 cb.cb_guid = vdev_guid;
1632                 cb.cb_type = ZPOOL_CONFIG_SPARES;
1633                 if (zpool_iter(hdl, find_aux, &cb) == 1) {
1634                         name = (char *)zpool_get_name(cb.cb_zhp);
1635                         ret = TRUE;
1636                 } else {
1637                         ret = FALSE;
1638                 }
1639                 break;
1640
1641         case POOL_STATE_L2CACHE:
1642
1643                 /*
1644                  * Check if any pool is currently using this l2cache device.
1645                  */
1646                 cb.cb_zhp = NULL;
1647                 cb.cb_guid = vdev_guid;
1648                 cb.cb_type = ZPOOL_CONFIG_L2CACHE;
1649                 if (zpool_iter(hdl, find_aux, &cb) == 1) {
1650                         name = (char *)zpool_get_name(cb.cb_zhp);
1651                         ret = TRUE;
1652                 } else {
1653                         ret = FALSE;
1654                 }
1655                 break;
1656
1657         default:
1658                 ret = B_FALSE;
1659         }
1660
1661
1662         if (ret) {
1663                 if ((*namestr = zfs_strdup(hdl, name)) == NULL) {
1664                         if (cb.cb_zhp)
1665                                 zpool_close(cb.cb_zhp);
1666                         nvlist_free(config);
1667                         return (-1);
1668                 }
1669                 *state = (pool_state_t)stateval;
1670         }
1671
1672         if (cb.cb_zhp)
1673                 zpool_close(cb.cb_zhp);
1674
1675         nvlist_free(config);
1676         *inuse = ret;
1677         return (0);
1678 }