sys/contrib/openzfs/lib/libzutil/zutil_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 2015 Nexenta Systems, Inc. All rights reserved.
  23  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Copyright (c) 2012, 2018 by Delphix. All rights reserved.
  25  * Copyright 2015 RackTop Systems.
  26  * Copyright (c) 2016, Intel Corporation.
  27  * Copyright (c) 2021, Colm Buckley <colm@tuatha.org>
  28  */
  29
  30 /*
  31  * Pool import support functions.
  32  *
  33  * Used by zpool, ztest, zdb, and zhack to locate importable configs. Since
  34  * these commands are expected to run in the global zone, we can assume
  35  * that the devices are all readable when called.
  36  *
  37  * To import a pool, we rely on reading the configuration information from the
  38  * ZFS label of each device.  If we successfully read the label, then we
  39  * organize the configuration information in the following hierarchy:
  40  *
  41  *      pool guid -> toplevel vdev guid -> label txg
  42  *
  43  * Duplicate entries matching this same tuple will be discarded.  Once we have
  44  * examined every device, we pick the best label txg config for each toplevel
  45  * vdev.  We then arrange these toplevel vdevs into a complete pool config, and
  46  * update any paths that have changed.  Finally, we attempt to import the pool
  47  * using our derived config, and record the results.
  48  */
  49
  50 #include <aio.h>
  51 #include <ctype.h>
  52 #include <dirent.h>
  53 #include <errno.h>
  54 #include <libintl.h>
  55 #include <libgen.h>
  56 #include <stddef.h>
  57 #include <stdlib.h>
  58 #include <string.h>
  59 #include <sys/stat.h>
  60 #include <unistd.h>
  61 #include <fcntl.h>
  62 #include <sys/dktp/fdisk.h>
  63 #include <sys/vdev_impl.h>
  64 #include <sys/fs/zfs.h>
  65 #include <sys/vdev_impl.h>
  66
  67 #include <thread_pool.h>
  68 #include <libzutil.h>
  69 #include <libnvpair.h>
  70
  71 #include "zutil_import.h"
  72
  73 /*PRINTFLIKE2*/
  74 static void
  75 zutil_error_aux(libpc_handle_t *hdl, const char *fmt, ...)
  76 {
  77         va_list ap;
  78
  79         va_start(ap, fmt);
  80
  81         (void) vsnprintf(hdl->lpc_desc, sizeof (hdl->lpc_desc), fmt, ap);
  82         hdl->lpc_desc_active = B_TRUE;
  83
  84         va_end(ap);
  85 }
  86
  87 static void
  88 zutil_verror(libpc_handle_t *hdl, const char *error, const char *fmt,
  89     va_list ap)
  90 {
  91         char action[1024];
  92
  93         (void) vsnprintf(action, sizeof (action), fmt, ap);
  94
  95         if (hdl->lpc_desc_active)
  96                 hdl->lpc_desc_active = B_FALSE;
  97         else
  98                 hdl->lpc_desc[0] = '\0';
  99
 100         if (hdl->lpc_printerr) {
 101                 if (hdl->lpc_desc[0] != '\0')
 102                         error = hdl->lpc_desc;
 103
 104                 (void) fprintf(stderr, "%s: %s\n", action, error);
 105         }
 106 }
 107
 108 /*PRINTFLIKE3*/
 109 static int
 110 zutil_error_fmt(libpc_handle_t *hdl, const char *error, const char *fmt, ...)
 111 {
 112         va_list ap;
 113
 114         va_start(ap, fmt);
 115
 116         zutil_verror(hdl, error, fmt, ap);
 117
 118         va_end(ap);
 119
 120         return (-1);
 121 }
 122
 123 static int
 124 zutil_error(libpc_handle_t *hdl, const char *error, const char *msg)
 125 {
 126         return (zutil_error_fmt(hdl, error, "%s", msg));
 127 }
 128
 129 static int
 130 zutil_no_memory(libpc_handle_t *hdl)
 131 {
 132         zutil_error(hdl, EZFS_NOMEM, "internal error");
 133         exit(1);
 134 }
 135
 136 void *
 137 zutil_alloc(libpc_handle_t *hdl, size_t size)
 138 {
 139         void *data;
 140
 141         if ((data = calloc(1, size)) == NULL)
 142                 (void) zutil_no_memory(hdl);
 143
 144         return (data);
 145 }
 146
 147 char *
 148 zutil_strdup(libpc_handle_t *hdl, const char *str)
 149 {
 150         char *ret;
 151
 152         if ((ret = strdup(str)) == NULL)
 153                 (void) zutil_no_memory(hdl);
 154
 155         return (ret);
 156 }
 157
 158 /*
 159  * Intermediate structures used to gather configuration information.
 160  */
 161 typedef struct config_entry {
 162         uint64_t                ce_txg;
 163         nvlist_t                *ce_config;
 164         struct config_entry     *ce_next;
 165 } config_entry_t;
 166
 167 typedef struct vdev_entry {
 168         uint64_t                ve_guid;
 169         config_entry_t          *ve_configs;
 170         struct vdev_entry       *ve_next;
 171 } vdev_entry_t;
 172
 173 typedef struct pool_entry {
 174         uint64_t                pe_guid;
 175         vdev_entry_t            *pe_vdevs;
 176         struct pool_entry       *pe_next;
 177 } pool_entry_t;
 178
 179 typedef struct name_entry {
 180         char                    *ne_name;
 181         uint64_t                ne_guid;
 182         uint64_t                ne_order;
 183         uint64_t                ne_num_labels;
 184         struct name_entry       *ne_next;
 185 } name_entry_t;
 186
 187 typedef struct pool_list {
 188         pool_entry_t            *pools;
 189         name_entry_t            *names;
 190 } pool_list_t;
 191
 192 /*
 193  * Go through and fix up any path and/or devid information for the given vdev
 194  * configuration.
 195  */
 196 static int
 197 fix_paths(libpc_handle_t *hdl, nvlist_t *nv, name_entry_t *names)
 198 {
 199         nvlist_t **child;
 200         uint_t c, children;
 201         uint64_t guid;
 202         name_entry_t *ne, *best;
 203         char *path;
 204
 205         if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
 206             &child, &children) == 0) {
 207                 for (c = 0; c < children; c++)
 208                         if (fix_paths(hdl, child[c], names) != 0)
 209                                 return (-1);
 210                 return (0);
 211         }
 212
 213         /*
 214          * This is a leaf (file or disk) vdev.  In either case, go through
 215          * the name list and see if we find a matching guid.  If so, replace
 216          * the path and see if we can calculate a new devid.
 217          *
 218          * There may be multiple names associated with a particular guid, in
 219          * which case we have overlapping partitions or multiple paths to the
 220          * same disk.  In this case we prefer to use the path name which
 221          * matches the ZPOOL_CONFIG_PATH.  If no matching entry is found we
 222          * use the lowest order device which corresponds to the first match
 223          * while traversing the ZPOOL_IMPORT_PATH search path.
 224          */
 225         verify(nvlist_lookup_uint64(nv, ZPOOL_CONFIG_GUID, &guid) == 0);
 226         if (nvlist_lookup_string(nv, ZPOOL_CONFIG_PATH, &path) != 0)
 227                 path = NULL;
 228
 229         best = NULL;
 230         for (ne = names; ne != NULL; ne = ne->ne_next) {
 231                 if (ne->ne_guid == guid) {
 232                         if (path == NULL) {
 233                                 best = ne;
 234                                 break;
 235                         }
 236
 237                         if ((strlen(path) == strlen(ne->ne_name)) &&
 238                             strncmp(path, ne->ne_name, strlen(path)) == 0) {
 239                                 best = ne;
 240                                 break;
 241                         }
 242
 243                         if (best == NULL) {
 244                                 best = ne;
 245                                 continue;
 246                         }
 247
 248                         /* Prefer paths with move vdev labels. */
 249                         if (ne->ne_num_labels > best->ne_num_labels) {
 250                                 best = ne;
 251                                 continue;
 252                         }
 253
 254                         /* Prefer paths earlier in the search order. */
 255                         if (ne->ne_num_labels == best->ne_num_labels &&
 256                             ne->ne_order < best->ne_order) {
 257                                 best = ne;
 258                                 continue;
 259                         }
 260                 }
 261         }
 262
 263         if (best == NULL)
 264                 return (0);
 265
 266         if (nvlist_add_string(nv, ZPOOL_CONFIG_PATH, best->ne_name) != 0)
 267                 return (-1);
 268
 269         update_vdev_config_dev_strs(nv);
 270
 271         return (0);
 272 }
 273
 274 /*
 275  * Add the given configuration to the list of known devices.
 276  */
 277 static int
 278 add_config(libpc_handle_t *hdl, pool_list_t *pl, const char *path,
 279     int order, int num_labels, nvlist_t *config)
 280 {
 281         uint64_t pool_guid, vdev_guid, top_guid, txg, state;
 282         pool_entry_t *pe;
 283         vdev_entry_t *ve;
 284         config_entry_t *ce;
 285         name_entry_t *ne;
 286
 287         /*
 288          * If this is a hot spare not currently in use or level 2 cache
 289          * device, add it to the list of names to translate, but don't do
 290          * anything else.
 291          */
 292         if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_STATE,
 293             &state) == 0 &&
 294             (state == POOL_STATE_SPARE || state == POOL_STATE_L2CACHE) &&
 295             nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID, &vdev_guid) == 0) {
 296                 if ((ne = zutil_alloc(hdl, sizeof (name_entry_t))) == NULL)
 297                         return (-1);
 298
 299                 if ((ne->ne_name = zutil_strdup(hdl, path)) == NULL) {
 300                         free(ne);
 301                         return (-1);
 302                 }
 303                 ne->ne_guid = vdev_guid;
 304                 ne->ne_order = order;
 305                 ne->ne_num_labels = num_labels;
 306                 ne->ne_next = pl->names;
 307                 pl->names = ne;
 308
 309                 return (0);
 310         }
 311
 312         /*
 313          * If we have a valid config but cannot read any of these fields, then
 314          * it means we have a half-initialized label.  In vdev_label_init()
 315          * we write a label with txg == 0 so that we can identify the device
 316          * in case the user refers to the same disk later on.  If we fail to
 317          * create the pool, we'll be left with a label in this state
 318          * which should not be considered part of a valid pool.
 319          */
 320         if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
 321             &pool_guid) != 0 ||
 322             nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID,
 323             &vdev_guid) != 0 ||
 324             nvlist_lookup_uint64(config, ZPOOL_CONFIG_TOP_GUID,
 325             &top_guid) != 0 ||
 326             nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_TXG,
 327             &txg) != 0 || txg == 0) {
 328                 return (0);
 329         }
 330
 331         /*
 332          * First, see if we know about this pool.  If not, then add it to the
 333          * list of known pools.
 334          */
 335         for (pe = pl->pools; pe != NULL; pe = pe->pe_next) {
 336                 if (pe->pe_guid == pool_guid)
 337                         break;
 338         }
 339
 340         if (pe == NULL) {
 341                 if ((pe = zutil_alloc(hdl, sizeof (pool_entry_t))) == NULL) {
 342                         return (-1);
 343                 }
 344                 pe->pe_guid = pool_guid;
 345                 pe->pe_next = pl->pools;
 346                 pl->pools = pe;
 347         }
 348
 349         /*
 350          * Second, see if we know about this toplevel vdev.  Add it if its
 351          * missing.
 352          */
 353         for (ve = pe->pe_vdevs; ve != NULL; ve = ve->ve_next) {
 354                 if (ve->ve_guid == top_guid)
 355                         break;
 356         }
 357
 358         if (ve == NULL) {
 359                 if ((ve = zutil_alloc(hdl, sizeof (vdev_entry_t))) == NULL) {
 360                         return (-1);
 361                 }
 362                 ve->ve_guid = top_guid;
 363                 ve->ve_next = pe->pe_vdevs;
 364                 pe->pe_vdevs = ve;
 365         }
 366
 367         /*
 368          * Third, see if we have a config with a matching transaction group.  If
 369          * so, then we do nothing.  Otherwise, add it to the list of known
 370          * configs.
 371          */
 372         for (ce = ve->ve_configs; ce != NULL; ce = ce->ce_next) {
 373                 if (ce->ce_txg == txg)
 374                         break;
 375         }
 376
 377         if (ce == NULL) {
 378                 if ((ce = zutil_alloc(hdl, sizeof (config_entry_t))) == NULL) {
 379                         return (-1);
 380                 }
 381                 ce->ce_txg = txg;
 382                 ce->ce_config = fnvlist_dup(config);
 383                 ce->ce_next = ve->ve_configs;
 384                 ve->ve_configs = ce;
 385         }
 386
 387         /*
 388          * At this point we've successfully added our config to the list of
 389          * known configs.  The last thing to do is add the vdev guid -> path
 390          * mappings so that we can fix up the configuration as necessary before
 391          * doing the import.
 392          */
 393         if ((ne = zutil_alloc(hdl, sizeof (name_entry_t))) == NULL)
 394                 return (-1);
 395
 396         if ((ne->ne_name = zutil_strdup(hdl, path)) == NULL) {
 397                 free(ne);
 398                 return (-1);
 399         }
 400
 401         ne->ne_guid = vdev_guid;
 402         ne->ne_order = order;
 403         ne->ne_num_labels = num_labels;
 404         ne->ne_next = pl->names;
 405         pl->names = ne;
 406
 407         return (0);
 408 }
 409
 410 static int
 411 zutil_pool_active(libpc_handle_t *hdl, const char *name, uint64_t guid,
 412     boolean_t *isactive)
 413 {
 414         ASSERT(hdl->lpc_ops->pco_pool_active != NULL);
 415
 416         int error = hdl->lpc_ops->pco_pool_active(hdl->lpc_lib_handle, name,
 417             guid, isactive);
 418
 419         return (error);
 420 }
 421
 422 static nvlist_t *
 423 zutil_refresh_config(libpc_handle_t *hdl, nvlist_t *tryconfig)
 424 {
 425         ASSERT(hdl->lpc_ops->pco_refresh_config != NULL);
 426
 427         return (hdl->lpc_ops->pco_refresh_config(hdl->lpc_lib_handle,
 428             tryconfig));
 429 }
 430
 431 /*
 432  * Determine if the vdev id is a hole in the namespace.
 433  */
 434 static boolean_t
 435 vdev_is_hole(uint64_t *hole_array, uint_t holes, uint_t id)
 436 {
 437         int c;
 438
 439         for (c = 0; c < holes; c++) {
 440
 441                 /* Top-level is a hole */
 442                 if (hole_array[c] == id)
 443                         return (B_TRUE);
 444         }
 445         return (B_FALSE);
 446 }
 447
 448 /*
 449  * Convert our list of pools into the definitive set of configurations.  We
 450  * start by picking the best config for each toplevel vdev.  Once that's done,
 451  * we assemble the toplevel vdevs into a full config for the pool.  We make a
 452  * pass to fix up any incorrect paths, and then add it to the main list to
 453  * return to the user.
 454  */
 455 static nvlist_t *
 456 get_configs(libpc_handle_t *hdl, pool_list_t *pl, boolean_t active_ok,
 457     nvlist_t *policy)
 458 {
 459         pool_entry_t *pe;
 460         vdev_entry_t *ve;
 461         config_entry_t *ce;
 462         nvlist_t *ret = NULL, *config = NULL, *tmp = NULL, *nvtop, *nvroot;
 463         nvlist_t **spares, **l2cache;
 464         uint_t i, nspares, nl2cache;
 465         boolean_t config_seen;
 466         uint64_t best_txg;
 467         char *name, *hostname = NULL;
 468         uint64_t guid;
 469         uint_t children = 0;
 470         nvlist_t **child = NULL;
 471         uint_t holes;
 472         uint64_t *hole_array, max_id;
 473         uint_t c;
 474         boolean_t isactive;
 475         uint64_t hostid;
 476         nvlist_t *nvl;
 477         boolean_t valid_top_config = B_FALSE;
 478
 479         if (nvlist_alloc(&ret, 0, 0) != 0)
 480                 goto nomem;
 481
 482         for (pe = pl->pools; pe != NULL; pe = pe->pe_next) {
 483                 uint64_t id, max_txg = 0;
 484
 485                 if (nvlist_alloc(&config, NV_UNIQUE_NAME, 0) != 0)
 486                         goto nomem;
 487                 config_seen = B_FALSE;
 488
 489                 /*
 490                  * Iterate over all toplevel vdevs.  Grab the pool configuration
 491                  * from the first one we find, and then go through the rest and
 492                  * add them as necessary to the 'vdevs' member of the config.
 493                  */
 494                 for (ve = pe->pe_vdevs; ve != NULL; ve = ve->ve_next) {
 495
 496                         /*
 497                          * Determine the best configuration for this vdev by
 498                          * selecting the config with the latest transaction
 499                          * group.
 500                          */
 501                         best_txg = 0;
 502                         for (ce = ve->ve_configs; ce != NULL;
 503                             ce = ce->ce_next) {
 504
 505                                 if (ce->ce_txg > best_txg) {
 506                                         tmp = ce->ce_config;
 507                                         best_txg = ce->ce_txg;
 508                                 }
 509                         }
 510
 511                         /*
 512                          * We rely on the fact that the max txg for the
 513                          * pool will contain the most up-to-date information
 514                          * about the valid top-levels in the vdev namespace.
 515                          */
 516                         if (best_txg > max_txg) {
 517                                 (void) nvlist_remove(config,
 518                                     ZPOOL_CONFIG_VDEV_CHILDREN,
 519                                     DATA_TYPE_UINT64);
 520                                 (void) nvlist_remove(config,
 521                                     ZPOOL_CONFIG_HOLE_ARRAY,
 522                                     DATA_TYPE_UINT64_ARRAY);
 523
 524                                 max_txg = best_txg;
 525                                 hole_array = NULL;
 526                                 holes = 0;
 527                                 max_id = 0;
 528                                 valid_top_config = B_FALSE;
 529
 530                                 if (nvlist_lookup_uint64(tmp,
 531                                     ZPOOL_CONFIG_VDEV_CHILDREN, &max_id) == 0) {
 532                                         verify(nvlist_add_uint64(config,
 533                                             ZPOOL_CONFIG_VDEV_CHILDREN,
 534                                             max_id) == 0);
 535                                         valid_top_config = B_TRUE;
 536                                 }
 537
 538                                 if (nvlist_lookup_uint64_array(tmp,
 539                                     ZPOOL_CONFIG_HOLE_ARRAY, &hole_array,
 540                                     &holes) == 0) {
 541                                         verify(nvlist_add_uint64_array(config,
 542                                             ZPOOL_CONFIG_HOLE_ARRAY,
 543                                             hole_array, holes) == 0);
 544                                 }
 545                         }
 546
 547                         if (!config_seen) {
 548                                 /*
 549                                  * Copy the relevant pieces of data to the pool
 550                                  * configuration:
 551                                  *
 552                                  *      version
 553                                  *      pool guid
 554                                  *      name
 555                                  *      comment (if available)
 556                                  *      compatibility features (if available)
 557                                  *      pool state
 558                                  *      hostid (if available)
 559                                  *      hostname (if available)
 560                                  */
 561                                 uint64_t state, version;
 562                                 char *comment = NULL;
 563                                 char *compatibility = NULL;
 564
 565                                 version = fnvlist_lookup_uint64(tmp,
 566                                     ZPOOL_CONFIG_VERSION);
 567                                 fnvlist_add_uint64(config,
 568                                     ZPOOL_CONFIG_VERSION, version);
 569                                 guid = fnvlist_lookup_uint64(tmp,
 570                                     ZPOOL_CONFIG_POOL_GUID);
 571                                 fnvlist_add_uint64(config,
 572                                     ZPOOL_CONFIG_POOL_GUID, guid);
 573                                 name = fnvlist_lookup_string(tmp,
 574                                     ZPOOL_CONFIG_POOL_NAME);
 575                                 fnvlist_add_string(config,
 576                                     ZPOOL_CONFIG_POOL_NAME, name);
 577
 578                                 if (nvlist_lookup_string(tmp,
 579                                     ZPOOL_CONFIG_COMMENT, &comment) == 0)
 580                                         fnvlist_add_string(config,
 581                                             ZPOOL_CONFIG_COMMENT, comment);
 582
 583                                 if (nvlist_lookup_string(tmp,
 584                                     ZPOOL_CONFIG_COMPATIBILITY,
 585                                     &compatibility) == 0)
 586                                         fnvlist_add_string(config,
 587                                             ZPOOL_CONFIG_COMPATIBILITY,
 588                                             compatibility);
 589
 590                                 state = fnvlist_lookup_uint64(tmp,
 591                                     ZPOOL_CONFIG_POOL_STATE);
 592                                 fnvlist_add_uint64(config,
 593                                     ZPOOL_CONFIG_POOL_STATE, state);
 594
 595                                 hostid = 0;
 596                                 if (nvlist_lookup_uint64(tmp,
 597                                     ZPOOL_CONFIG_HOSTID, &hostid) == 0) {
 598                                         fnvlist_add_uint64(config,
 599                                             ZPOOL_CONFIG_HOSTID, hostid);
 600                                         hostname = fnvlist_lookup_string(tmp,
 601                                             ZPOOL_CONFIG_HOSTNAME);
 602                                         fnvlist_add_string(config,
 603                                             ZPOOL_CONFIG_HOSTNAME, hostname);
 604                                 }
 605
 606                                 config_seen = B_TRUE;
 607                         }
 608
 609                         /*
 610                          * Add this top-level vdev to the child array.
 611                          */
 612                         verify(nvlist_lookup_nvlist(tmp,
 613                             ZPOOL_CONFIG_VDEV_TREE, &nvtop) == 0);
 614                         verify(nvlist_lookup_uint64(nvtop, ZPOOL_CONFIG_ID,
 615                             &id) == 0);
 616
 617                         if (id >= children) {
 618                                 nvlist_t **newchild;
 619
 620                                 newchild = zutil_alloc(hdl, (id + 1) *
 621                                     sizeof (nvlist_t *));
 622                                 if (newchild == NULL)
 623                                         goto nomem;
 624
 625                                 for (c = 0; c < children; c++)
 626                                         newchild[c] = child[c];
 627
 628                                 free(child);
 629                                 child = newchild;
 630                                 children = id + 1;
 631                         }
 632                         if (nvlist_dup(nvtop, &child[id], 0) != 0)
 633                                 goto nomem;
 634
 635                 }
 636
 637                 /*
 638                  * If we have information about all the top-levels then
 639                  * clean up the nvlist which we've constructed. This
 640                  * means removing any extraneous devices that are
 641                  * beyond the valid range or adding devices to the end
 642                  * of our array which appear to be missing.
 643                  */
 644                 if (valid_top_config) {
 645                         if (max_id < children) {
 646                                 for (c = max_id; c < children; c++)
 647                                         nvlist_free(child[c]);
 648                                 children = max_id;
 649                         } else if (max_id > children) {
 650                                 nvlist_t **newchild;
 651
 652                                 newchild = zutil_alloc(hdl, (max_id) *
 653                                     sizeof (nvlist_t *));
 654                                 if (newchild == NULL)
 655                                         goto nomem;
 656
 657                                 for (c = 0; c < children; c++)
 658                                         newchild[c] = child[c];
 659
 660                                 free(child);
 661                                 child = newchild;
 662                                 children = max_id;
 663                         }
 664                 }
 665
 666                 verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
 667                     &guid) == 0);
 668
 669                 /*
 670                  * The vdev namespace may contain holes as a result of
 671                  * device removal. We must add them back into the vdev
 672                  * tree before we process any missing devices.
 673                  */
 674                 if (holes > 0) {
 675                         ASSERT(valid_top_config);
 676
 677                         for (c = 0; c < children; c++) {
 678                                 nvlist_t *holey;
 679
 680                                 if (child[c] != NULL ||
 681                                     !vdev_is_hole(hole_array, holes, c))
 682                                         continue;
 683
 684                                 if (nvlist_alloc(&holey, NV_UNIQUE_NAME,
 685                                     0) != 0)
 686                                         goto nomem;
 687
 688                                 /*
 689                                  * Holes in the namespace are treated as
 690                                  * "hole" top-level vdevs and have a
 691                                  * special flag set on them.
 692                                  */
 693                                 if (nvlist_add_string(holey,
 694                                     ZPOOL_CONFIG_TYPE,
 695                                     VDEV_TYPE_HOLE) != 0 ||
 696                                     nvlist_add_uint64(holey,
 697                                     ZPOOL_CONFIG_ID, c) != 0 ||
 698                                     nvlist_add_uint64(holey,
 699                                     ZPOOL_CONFIG_GUID, 0ULL) != 0) {
 700                                         nvlist_free(holey);
 701                                         goto nomem;
 702                                 }
 703                                 child[c] = holey;
 704                         }
 705                 }
 706
 707                 /*
 708                  * Look for any missing top-level vdevs.  If this is the case,
 709                  * create a faked up 'missing' vdev as a placeholder.  We cannot
 710                  * simply compress the child array, because the kernel performs
 711                  * certain checks to make sure the vdev IDs match their location
 712                  * in the configuration.
 713                  */
 714                 for (c = 0; c < children; c++) {
 715                         if (child[c] == NULL) {
 716                                 nvlist_t *missing;
 717                                 if (nvlist_alloc(&missing, NV_UNIQUE_NAME,
 718                                     0) != 0)
 719                                         goto nomem;
 720                                 if (nvlist_add_string(missing,
 721                                     ZPOOL_CONFIG_TYPE,
 722                                     VDEV_TYPE_MISSING) != 0 ||
 723                                     nvlist_add_uint64(missing,
 724                                     ZPOOL_CONFIG_ID, c) != 0 ||
 725                                     nvlist_add_uint64(missing,
 726                                     ZPOOL_CONFIG_GUID, 0ULL) != 0) {
 727                                         nvlist_free(missing);
 728                                         goto nomem;
 729                                 }
 730                                 child[c] = missing;
 731                         }
 732                 }
 733
 734                 /*
 735                  * Put all of this pool's top-level vdevs into a root vdev.
 736                  */
 737                 if (nvlist_alloc(&nvroot, NV_UNIQUE_NAME, 0) != 0)
 738                         goto nomem;
 739                 if (nvlist_add_string(nvroot, ZPOOL_CONFIG_TYPE,
 740                     VDEV_TYPE_ROOT) != 0 ||
 741                     nvlist_add_uint64(nvroot, ZPOOL_CONFIG_ID, 0ULL) != 0 ||
 742                     nvlist_add_uint64(nvroot, ZPOOL_CONFIG_GUID, guid) != 0 ||
 743                     nvlist_add_nvlist_array(nvroot, ZPOOL_CONFIG_CHILDREN,
 744                     child, children) != 0) {
 745                         nvlist_free(nvroot);
 746                         goto nomem;
 747                 }
 748
 749                 for (c = 0; c < children; c++)
 750                         nvlist_free(child[c]);
 751                 free(child);
 752                 children = 0;
 753                 child = NULL;
 754
 755                 /*
 756                  * Go through and fix up any paths and/or devids based on our
 757                  * known list of vdev GUID -> path mappings.
 758                  */
 759                 if (fix_paths(hdl, nvroot, pl->names) != 0) {
 760                         nvlist_free(nvroot);
 761                         goto nomem;
 762                 }
 763
 764                 /*
 765                  * Add the root vdev to this pool's configuration.
 766                  */
 767                 if (nvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
 768                     nvroot) != 0) {
 769                         nvlist_free(nvroot);
 770                         goto nomem;
 771                 }
 772                 nvlist_free(nvroot);
 773
 774                 /*
 775                  * zdb uses this path to report on active pools that were
 776                  * imported or created using -R.
 777                  */
 778                 if (active_ok)
 779                         goto add_pool;
 780
 781                 /*
 782                  * Determine if this pool is currently active, in which case we
 783                  * can't actually import it.
 784                  */
 785                 verify(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
 786                     &name) == 0);
 787                 verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
 788                     &guid) == 0);
 789
 790                 if (zutil_pool_active(hdl, name, guid, &isactive) != 0)
 791                         goto error;
 792
 793                 if (isactive) {
 794                         nvlist_free(config);
 795                         config = NULL;
 796                         continue;
 797                 }
 798
 799                 if (policy != NULL) {
 800                         if (nvlist_add_nvlist(config, ZPOOL_LOAD_POLICY,
 801                             policy) != 0)
 802                                 goto nomem;
 803                 }
 804
 805                 if ((nvl = zutil_refresh_config(hdl, config)) == NULL) {
 806                         nvlist_free(config);
 807                         config = NULL;
 808                         continue;
 809                 }
 810
 811                 nvlist_free(config);
 812                 config = nvl;
 813
 814                 /*
 815                  * Go through and update the paths for spares, now that we have
 816                  * them.
 817                  */
 818                 verify(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
 819                     &nvroot) == 0);
 820                 if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES,
 821                     &spares, &nspares) == 0) {
 822                         for (i = 0; i < nspares; i++) {
 823                                 if (fix_paths(hdl, spares[i], pl->names) != 0)
 824                                         goto nomem;
 825                         }
 826                 }
 827
 828                 /*
 829                  * Update the paths for l2cache devices.
 830                  */
 831                 if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_L2CACHE,
 832                     &l2cache, &nl2cache) == 0) {
 833                         for (i = 0; i < nl2cache; i++) {
 834                                 if (fix_paths(hdl, l2cache[i], pl->names) != 0)
 835                                         goto nomem;
 836                         }
 837                 }
 838
 839                 /*
 840                  * Restore the original information read from the actual label.
 841                  */
 842                 (void) nvlist_remove(config, ZPOOL_CONFIG_HOSTID,
 843                     DATA_TYPE_UINT64);
 844                 (void) nvlist_remove(config, ZPOOL_CONFIG_HOSTNAME,
 845                     DATA_TYPE_STRING);
 846                 if (hostid != 0) {
 847                         verify(nvlist_add_uint64(config, ZPOOL_CONFIG_HOSTID,
 848                             hostid) == 0);
 849                         verify(nvlist_add_string(config, ZPOOL_CONFIG_HOSTNAME,
 850                             hostname) == 0);
 851                 }
 852
 853 add_pool:
 854                 /*
 855                  * Add this pool to the list of configs.
 856                  */
 857                 verify(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
 858                     &name) == 0);
 859
 860                 if (nvlist_add_nvlist(ret, name, config) != 0)
 861                         goto nomem;
 862
 863                 nvlist_free(config);
 864                 config = NULL;
 865         }
 866
 867         return (ret);
 868
 869 nomem:
 870         (void) zutil_no_memory(hdl);
 871 error:
 872         nvlist_free(config);
 873         nvlist_free(ret);
 874         for (c = 0; c < children; c++)
 875                 nvlist_free(child[c]);
 876         free(child);
 877
 878         return (NULL);
 879 }
 880
 881 /*
 882  * Return the offset of the given label.
 883  */
 884 static uint64_t
 885 label_offset(uint64_t size, int l)
 886 {
 887         ASSERT(P2PHASE_TYPED(size, sizeof (vdev_label_t), uint64_t) == 0);
 888         return (l * sizeof (vdev_label_t) + (l < VDEV_LABELS / 2 ?
 889             0 : size - VDEV_LABELS * sizeof (vdev_label_t)));
 890 }
 891
 892 /*
 893  * Given a file descriptor, read the label information and return an nvlist
 894  * describing the configuration, if there is one.  The number of valid
 895  * labels found will be returned in num_labels when non-NULL.
 896  */
 897 int
 898 zpool_read_label(int fd, nvlist_t **config, int *num_labels)
 899 {
 900         struct stat64 statbuf;
 901         struct aiocb aiocbs[VDEV_LABELS];
 902         struct aiocb *aiocbps[VDEV_LABELS];
 903         vdev_phys_t *labels;
 904         nvlist_t *expected_config = NULL;
 905         uint64_t expected_guid = 0, size;
 906         int error, l, count = 0;
 907
 908         *config = NULL;
 909
 910         if (fstat64_blk(fd, &statbuf) == -1)
 911                 return (0);
 912         size = P2ALIGN_TYPED(statbuf.st_size, sizeof (vdev_label_t), uint64_t);
 913
 914         error = posix_memalign((void **)&labels, PAGESIZE,
 915             VDEV_LABELS * sizeof (*labels));
 916         if (error)
 917                 return (-1);
 918
 919         memset(aiocbs, 0, sizeof (aiocbs));
 920         for (l = 0; l < VDEV_LABELS; l++) {
 921                 off_t offset = label_offset(size, l) + VDEV_SKIP_SIZE;
 922
 923                 aiocbs[l].aio_fildes = fd;
 924                 aiocbs[l].aio_offset = offset;
 925                 aiocbs[l].aio_buf = &labels[l];
 926                 aiocbs[l].aio_nbytes = sizeof (vdev_phys_t);
 927                 aiocbs[l].aio_lio_opcode = LIO_READ;
 928                 aiocbps[l] = &aiocbs[l];
 929         }
 930
 931         if (lio_listio(LIO_WAIT, aiocbps, VDEV_LABELS, NULL) != 0) {
 932                 int saved_errno = errno;
 933
 934                 if (errno == EAGAIN || errno == EINTR || errno == EIO) {
 935                         /*
 936                          * A portion of the requests may have been submitted.
 937                          * Clean them up.
 938                          */
 939                         for (l = 0; l < VDEV_LABELS; l++) {
 940                                 errno = 0;
 941                                 int r = aio_error(&aiocbs[l]);
 942                                 if (r != EINVAL)
 943                                         (void) aio_return(&aiocbs[l]);
 944                         }
 945                 }
 946                 free(labels);
 947                 errno = saved_errno;
 948                 return (-1);
 949         }
 950
 951         for (l = 0; l < VDEV_LABELS; l++) {
 952                 uint64_t state, guid, txg;
 953
 954                 if (aio_return(&aiocbs[l]) != sizeof (vdev_phys_t))
 955                         continue;
 956
 957                 if (nvlist_unpack(labels[l].vp_nvlist,
 958                     sizeof (labels[l].vp_nvlist), config, 0) != 0)
 959                         continue;
 960
 961                 if (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_GUID,
 962                     &guid) != 0 || guid == 0) {
 963                         nvlist_free(*config);
 964                         continue;
 965                 }
 966
 967                 if (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_STATE,
 968                     &state) != 0 || state > POOL_STATE_L2CACHE) {
 969                         nvlist_free(*config);
 970                         continue;
 971                 }
 972
 973                 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE &&
 974                     (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_TXG,
 975                     &txg) != 0 || txg == 0)) {
 976                         nvlist_free(*config);
 977                         continue;
 978                 }
 979
 980                 if (expected_guid) {
 981                         if (expected_guid == guid)
 982                                 count++;
 983
 984                         nvlist_free(*config);
 985                 } else {
 986                         expected_config = *config;
 987                         expected_guid = guid;
 988                         count++;
 989                 }
 990         }
 991
 992         if (num_labels != NULL)
 993                 *num_labels = count;
 994
 995         free(labels);
 996         *config = expected_config;
 997
 998         return (0);
 999 }
1000
1001 /*
1002  * Sorted by full path and then vdev guid to allow for multiple entries with
1003  * the same full path name.  This is required because it's possible to
1004  * have multiple block devices with labels that refer to the same
1005  * ZPOOL_CONFIG_PATH yet have different vdev guids.  In this case both
1006  * entries need to be added to the cache.  Scenarios where this can occur
1007  * include overwritten pool labels, devices which are visible from multiple
1008  * hosts and multipath devices.
1009  */
1010 int
1011 slice_cache_compare(const void *arg1, const void *arg2)
1012 {
1013         const char  *nm1 = ((rdsk_node_t *)arg1)->rn_name;
1014         const char  *nm2 = ((rdsk_node_t *)arg2)->rn_name;
1015         uint64_t guid1 = ((rdsk_node_t *)arg1)->rn_vdev_guid;
1016         uint64_t guid2 = ((rdsk_node_t *)arg2)->rn_vdev_guid;
1017         int rv;
1018
1019         rv = TREE_ISIGN(strcmp(nm1, nm2));
1020         if (rv)
1021                 return (rv);
1022
1023         return (TREE_CMP(guid1, guid2));
1024 }
1025
1026 static int
1027 label_paths_impl(libpc_handle_t *hdl, nvlist_t *nvroot, uint64_t pool_guid,
1028     uint64_t vdev_guid, char **path, char **devid)
1029 {
1030         nvlist_t **child;
1031         uint_t c, children;
1032         uint64_t guid;
1033         char *val;
1034         int error;
1035
1036         if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_CHILDREN,
1037             &child, &children) == 0) {
1038                 for (c = 0; c < children; c++) {
1039                         error  = label_paths_impl(hdl, child[c],
1040                             pool_guid, vdev_guid, path, devid);
1041                         if (error)
1042                                 return (error);
1043                 }
1044                 return (0);
1045         }
1046
1047         if (nvroot == NULL)
1048                 return (0);
1049
1050         error = nvlist_lookup_uint64(nvroot, ZPOOL_CONFIG_GUID, &guid);
1051         if ((error != 0) || (guid != vdev_guid))
1052                 return (0);
1053
1054         error = nvlist_lookup_string(nvroot, ZPOOL_CONFIG_PATH, &val);
1055         if (error == 0)
1056                 *path = val;
1057
1058         error = nvlist_lookup_string(nvroot, ZPOOL_CONFIG_DEVID, &val);
1059         if (error == 0)
1060                 *devid = val;
1061
1062         return (0);
1063 }
1064
1065 /*
1066  * Given a disk label fetch the ZPOOL_CONFIG_PATH and ZPOOL_CONFIG_DEVID
1067  * and store these strings as config_path and devid_path respectively.
1068  * The returned pointers are only valid as long as label remains valid.
1069  */
1070 int
1071 label_paths(libpc_handle_t *hdl, nvlist_t *label, char **path, char **devid)
1072 {
1073         nvlist_t *nvroot;
1074         uint64_t pool_guid;
1075         uint64_t vdev_guid;
1076
1077         *path = NULL;
1078         *devid = NULL;
1079
1080         if (nvlist_lookup_nvlist(label, ZPOOL_CONFIG_VDEV_TREE, &nvroot) ||
1081             nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_GUID, &pool_guid) ||
1082             nvlist_lookup_uint64(label, ZPOOL_CONFIG_GUID, &vdev_guid))
1083                 return (ENOENT);
1084
1085         return (label_paths_impl(hdl, nvroot, pool_guid, vdev_guid, path,
1086             devid));
1087 }
1088
1089 static void
1090 zpool_find_import_scan_add_slice(libpc_handle_t *hdl, pthread_mutex_t *lock,
1091     avl_tree_t *cache, const char *path, const char *name, int order)
1092 {
1093         avl_index_t where;
1094         rdsk_node_t *slice;
1095
1096         slice = zutil_alloc(hdl, sizeof (rdsk_node_t));
1097         if (asprintf(&slice->rn_name, "%s/%s", path, name) == -1) {
1098                 free(slice);
1099                 return;
1100         }
1101         slice->rn_vdev_guid = 0;
1102         slice->rn_lock = lock;
1103         slice->rn_avl = cache;
1104         slice->rn_hdl = hdl;
1105         slice->rn_order = order + IMPORT_ORDER_SCAN_OFFSET;
1106         slice->rn_labelpaths = B_FALSE;
1107
1108         pthread_mutex_lock(lock);
1109         if (avl_find(cache, slice, &where)) {
1110                 free(slice->rn_name);
1111                 free(slice);
1112         } else {
1113                 avl_insert(cache, slice, where);
1114         }
1115         pthread_mutex_unlock(lock);
1116 }
1117
1118 static int
1119 zpool_find_import_scan_dir(libpc_handle_t *hdl, pthread_mutex_t *lock,
1120     avl_tree_t *cache, const char *dir, int order)
1121 {
1122         int error;
1123         char path[MAXPATHLEN];
1124         struct dirent64 *dp;
1125         DIR *dirp;
1126
1127         if (realpath(dir, path) == NULL) {
1128                 error = errno;
1129                 if (error == ENOENT)
1130                         return (0);
1131
1132                 zutil_error_aux(hdl, strerror(error));
1133                 (void) zutil_error_fmt(hdl, EZFS_BADPATH, dgettext(
1134                     TEXT_DOMAIN, "cannot resolve path '%s'"), dir);
1135                 return (error);
1136         }
1137
1138         dirp = opendir(path);
1139         if (dirp == NULL) {
1140                 error = errno;
1141                 zutil_error_aux(hdl, strerror(error));
1142                 (void) zutil_error_fmt(hdl, EZFS_BADPATH,
1143                     dgettext(TEXT_DOMAIN, "cannot open '%s'"), path);
1144                 return (error);
1145         }
1146
1147         while ((dp = readdir64(dirp)) != NULL) {
1148                 const char *name = dp->d_name;
1149                 if (name[0] == '.' &&
1150                     (name[1] == 0 || (name[1] == '.' && name[2] == 0)))
1151                         continue;
1152
1153                 zpool_find_import_scan_add_slice(hdl, lock, cache, path, name,
1154                     order);
1155         }
1156
1157         (void) closedir(dirp);
1158         return (0);
1159 }
1160
1161 static int
1162 zpool_find_import_scan_path(libpc_handle_t *hdl, pthread_mutex_t *lock,
1163     avl_tree_t *cache, const char *dir, int order)
1164 {
1165         int error = 0;
1166         char path[MAXPATHLEN];
1167         char *d, *b;
1168         char *dpath, *name;
1169
1170         /*
1171          * Separate the directory part and last part of the
1172          * path. We do this so that we can get the realpath of
1173          * the directory. We don't get the realpath on the
1174          * whole path because if it's a symlink, we want the
1175          * path of the symlink not where it points to.
1176          */
1177         d = zutil_strdup(hdl, dir);
1178         b = zutil_strdup(hdl, dir);
1179         dpath = dirname(d);
1180         name = basename(b);
1181
1182         if (realpath(dpath, path) == NULL) {
1183                 error = errno;
1184                 if (error == ENOENT) {
1185                         error = 0;
1186                         goto out;
1187                 }
1188
1189                 zutil_error_aux(hdl, strerror(error));
1190                 (void) zutil_error_fmt(hdl, EZFS_BADPATH, dgettext(
1191                     TEXT_DOMAIN, "cannot resolve path '%s'"), dir);
1192                 goto out;
1193         }
1194
1195         zpool_find_import_scan_add_slice(hdl, lock, cache, path, name, order);
1196
1197 out:
1198         free(b);
1199         free(d);
1200         return (error);
1201 }
1202
1203 /*
1204  * Scan a list of directories for zfs devices.
1205  */
1206 static int
1207 zpool_find_import_scan(libpc_handle_t *hdl, pthread_mutex_t *lock,
1208     avl_tree_t **slice_cache, const char * const *dir, size_t dirs)
1209 {
1210         avl_tree_t *cache;
1211         rdsk_node_t *slice;
1212         void *cookie;
1213         int i, error;
1214
1215         *slice_cache = NULL;
1216         cache = zutil_alloc(hdl, sizeof (avl_tree_t));
1217         avl_create(cache, slice_cache_compare, sizeof (rdsk_node_t),
1218             offsetof(rdsk_node_t, rn_node));
1219
1220         for (i = 0; i < dirs; i++) {
1221                 struct stat sbuf;
1222
1223                 if (stat(dir[i], &sbuf) != 0) {
1224                         error = errno;
1225                         if (error == ENOENT)
1226                                 continue;
1227
1228                         zutil_error_aux(hdl, strerror(error));
1229                         (void) zutil_error_fmt(hdl, EZFS_BADPATH, dgettext(
1230                             TEXT_DOMAIN, "cannot resolve path '%s'"), dir[i]);
1231                         goto error;
1232                 }
1233
1234                 /*
1235                  * If dir[i] is a directory, we walk through it and add all
1236                  * the entries to the cache. If it's not a directory, we just
1237                  * add it to the cache.
1238                  */
1239                 if (S_ISDIR(sbuf.st_mode)) {
1240                         if ((error = zpool_find_import_scan_dir(hdl, lock,
1241                             cache, dir[i], i)) != 0)
1242                                 goto error;
1243                 } else {
1244                         if ((error = zpool_find_import_scan_path(hdl, lock,
1245                             cache, dir[i], i)) != 0)
1246                                 goto error;
1247                 }
1248         }
1249
1250         *slice_cache = cache;
1251         return (0);
1252
1253 error:
1254         cookie = NULL;
1255         while ((slice = avl_destroy_nodes(cache, &cookie)) != NULL) {
1256                 free(slice->rn_name);
1257                 free(slice);
1258         }
1259         free(cache);
1260
1261         return (error);
1262 }
1263
1264 /*
1265  * Given a list of directories to search, find all pools stored on disk.  This
1266  * includes partial pools which are not available to import.  If no args are
1267  * given (argc is 0), then the default directory (/dev/dsk) is searched.
1268  * poolname or guid (but not both) are provided by the caller when trying
1269  * to import a specific pool.
1270  */
1271 static nvlist_t *
1272 zpool_find_import_impl(libpc_handle_t *hdl, importargs_t *iarg,
1273     pthread_mutex_t *lock, avl_tree_t *cache)
1274 {
1275         nvlist_t *ret = NULL;
1276         pool_list_t pools = { 0 };
1277         pool_entry_t *pe, *penext;
1278         vdev_entry_t *ve, *venext;
1279         config_entry_t *ce, *cenext;
1280         name_entry_t *ne, *nenext;
1281         rdsk_node_t *slice;
1282         void *cookie;
1283         tpool_t *t;
1284
1285         verify(iarg->poolname == NULL || iarg->guid == 0);
1286
1287         /*
1288          * Create a thread pool to parallelize the process of reading and
1289          * validating labels, a large number of threads can be used due to
1290          * minimal contention.
1291          */
1292         t = tpool_create(1, 2 * sysconf(_SC_NPROCESSORS_ONLN), 0, NULL);
1293         for (slice = avl_first(cache); slice;
1294             (slice = avl_walk(cache, slice, AVL_AFTER)))
1295                 (void) tpool_dispatch(t, zpool_open_func, slice);
1296
1297         tpool_wait(t);
1298         tpool_destroy(t);
1299
1300         /*
1301          * Process the cache, filtering out any entries which are not
1302          * for the specified pool then adding matching label configs.
1303          */
1304         cookie = NULL;
1305         while ((slice = avl_destroy_nodes(cache, &cookie)) != NULL) {
1306                 if (slice->rn_config != NULL) {
1307                         nvlist_t *config = slice->rn_config;
1308                         boolean_t matched = B_TRUE;
1309                         boolean_t aux = B_FALSE;
1310                         int fd;
1311
1312                         /*
1313                          * Check if it's a spare or l2cache device. If it is,
1314                          * we need to skip the name and guid check since they
1315                          * don't exist on aux device label.
1316                          */
1317                         if (iarg->poolname != NULL || iarg->guid != 0) {
1318                                 uint64_t state;
1319                                 aux = nvlist_lookup_uint64(config,
1320                                     ZPOOL_CONFIG_POOL_STATE, &state) == 0 &&
1321                                     (state == POOL_STATE_SPARE ||
1322                                     state == POOL_STATE_L2CACHE);
1323                         }
1324
1325                         if (iarg->poolname != NULL && !aux) {
1326                                 char *pname;
1327
1328                                 matched = nvlist_lookup_string(config,
1329                                     ZPOOL_CONFIG_POOL_NAME, &pname) == 0 &&
1330                                     strcmp(iarg->poolname, pname) == 0;
1331                         } else if (iarg->guid != 0 && !aux) {
1332                                 uint64_t this_guid;
1333
1334                                 matched = nvlist_lookup_uint64(config,
1335                                     ZPOOL_CONFIG_POOL_GUID, &this_guid) == 0 &&
1336                                     iarg->guid == this_guid;
1337                         }
1338                         if (matched) {
1339                                 /*
1340                                  * Verify all remaining entries can be opened
1341                                  * exclusively. This will prune all underlying
1342                                  * multipath devices which otherwise could
1343                                  * result in the vdev appearing as UNAVAIL.
1344                                  *
1345                                  * Under zdb, this step isn't required and
1346                                  * would prevent a zdb -e of active pools with
1347                                  * no cachefile.
1348                                  */
1349                                 fd = open(slice->rn_name, O_RDONLY | O_EXCL);
1350                                 if (fd >= 0 || iarg->can_be_active) {
1351                                         if (fd >= 0)
1352                                                 close(fd);
1353                                         add_config(hdl, &pools,
1354                                             slice->rn_name, slice->rn_order,
1355                                             slice->rn_num_labels, config);
1356                                 }
1357                         }
1358                         nvlist_free(config);
1359                 }
1360                 free(slice->rn_name);
1361                 free(slice);
1362         }
1363         avl_destroy(cache);
1364         free(cache);
1365
1366         ret = get_configs(hdl, &pools, iarg->can_be_active, iarg->policy);
1367
1368         for (pe = pools.pools; pe != NULL; pe = penext) {
1369                 penext = pe->pe_next;
1370                 for (ve = pe->pe_vdevs; ve != NULL; ve = venext) {
1371                         venext = ve->ve_next;
1372                         for (ce = ve->ve_configs; ce != NULL; ce = cenext) {
1373                                 cenext = ce->ce_next;
1374                                 nvlist_free(ce->ce_config);
1375                                 free(ce);
1376                         }
1377                         free(ve);
1378                 }
1379                 free(pe);
1380         }
1381
1382         for (ne = pools.names; ne != NULL; ne = nenext) {
1383                 nenext = ne->ne_next;
1384                 free(ne->ne_name);
1385                 free(ne);
1386         }
1387
1388         return (ret);
1389 }
1390
1391 /*
1392  * Given a config, discover the paths for the devices which
1393  * exist in the config.
1394  */
1395 static int
1396 discover_cached_paths(libpc_handle_t *hdl, nvlist_t *nv,
1397     avl_tree_t *cache, pthread_mutex_t *lock)
1398 {
1399         char *path = NULL;
1400         uint_t children;
1401         nvlist_t **child;
1402
1403         if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
1404             &child, &children) == 0) {
1405                 for (int c = 0; c < children; c++) {
1406                         discover_cached_paths(hdl, child[c], cache, lock);
1407                 }
1408         }
1409
1410         /*
1411          * Once we have the path, we need to add the directory to
1412          * our directoy cache.
1413          */
1414         if (nvlist_lookup_string(nv, ZPOOL_CONFIG_PATH, &path) == 0) {
1415                 return (zpool_find_import_scan_dir(hdl, lock, cache,
1416                     dirname(path), 0));
1417         }
1418         return (0);
1419 }
1420
1421 /*
1422  * Given a cache file, return the contents as a list of importable pools.
1423  * poolname or guid (but not both) are provided by the caller when trying
1424  * to import a specific pool.
1425  */
1426 static nvlist_t *
1427 zpool_find_import_cached(libpc_handle_t *hdl, importargs_t *iarg)
1428 {
1429         char *buf;
1430         int fd;
1431         struct stat64 statbuf;
1432         nvlist_t *raw, *src, *dst;
1433         nvlist_t *pools;
1434         nvpair_t *elem;
1435         char *name;
1436         uint64_t this_guid;
1437         boolean_t active;
1438
1439         verify(iarg->poolname == NULL || iarg->guid == 0);
1440
1441         if ((fd = open(iarg->cachefile, O_RDONLY)) < 0) {
1442                 zutil_error_aux(hdl, "%s", strerror(errno));
1443                 (void) zutil_error(hdl, EZFS_BADCACHE,
1444                     dgettext(TEXT_DOMAIN, "failed to open cache file"));
1445                 return (NULL);
1446         }
1447
1448         if (fstat64(fd, &statbuf) != 0) {
1449                 zutil_error_aux(hdl, "%s", strerror(errno));
1450                 (void) close(fd);
1451                 (void) zutil_error(hdl, EZFS_BADCACHE,
1452                     dgettext(TEXT_DOMAIN, "failed to get size of cache file"));
1453                 return (NULL);
1454         }
1455
1456         if ((buf = zutil_alloc(hdl, statbuf.st_size)) == NULL) {
1457                 (void) close(fd);
1458                 return (NULL);
1459         }
1460
1461         if (read(fd, buf, statbuf.st_size) != statbuf.st_size) {
1462                 (void) close(fd);
1463                 free(buf);
1464                 (void) zutil_error(hdl, EZFS_BADCACHE,
1465                     dgettext(TEXT_DOMAIN,
1466                     "failed to read cache file contents"));
1467                 return (NULL);
1468         }
1469
1470         (void) close(fd);
1471
1472         if (nvlist_unpack(buf, statbuf.st_size, &raw, 0) != 0) {
1473                 free(buf);
1474                 (void) zutil_error(hdl, EZFS_BADCACHE,
1475                     dgettext(TEXT_DOMAIN,
1476                     "invalid or corrupt cache file contents"));
1477                 return (NULL);
1478         }
1479
1480         free(buf);
1481
1482         /*
1483          * Go through and get the current state of the pools and refresh their
1484          * state.
1485          */
1486         if (nvlist_alloc(&pools, 0, 0) != 0) {
1487                 (void) zutil_no_memory(hdl);
1488                 nvlist_free(raw);
1489                 return (NULL);
1490         }
1491
1492         elem = NULL;
1493         while ((elem = nvlist_next_nvpair(raw, elem)) != NULL) {
1494                 src = fnvpair_value_nvlist(elem);
1495
1496                 name = fnvlist_lookup_string(src, ZPOOL_CONFIG_POOL_NAME);
1497                 if (iarg->poolname != NULL && strcmp(iarg->poolname, name) != 0)
1498                         continue;
1499
1500                 this_guid = fnvlist_lookup_uint64(src, ZPOOL_CONFIG_POOL_GUID);
1501                 if (iarg->guid != 0 && iarg->guid != this_guid)
1502                         continue;
1503
1504                 if (zutil_pool_active(hdl, name, this_guid, &active) != 0) {
1505                         nvlist_free(raw);
1506                         nvlist_free(pools);
1507                         return (NULL);
1508                 }
1509
1510                 if (active)
1511                         continue;
1512
1513                 if (iarg->scan) {
1514                         uint64_t saved_guid = iarg->guid;
1515                         const char *saved_poolname = iarg->poolname;
1516                         pthread_mutex_t lock;
1517
1518                         /*
1519                          * Create the device cache that will hold the
1520                          * devices we will scan based on the cachefile.
1521                          * This will get destroyed and freed by
1522                          * zpool_find_import_impl.
1523                          */
1524                         avl_tree_t *cache = zutil_alloc(hdl,
1525                             sizeof (avl_tree_t));
1526                         avl_create(cache, slice_cache_compare,
1527                             sizeof (rdsk_node_t),
1528                             offsetof(rdsk_node_t, rn_node));
1529                         nvlist_t *nvroot = fnvlist_lookup_nvlist(src,
1530                             ZPOOL_CONFIG_VDEV_TREE);
1531
1532                         /*
1533                          * We only want to find the pool with this_guid.
1534                          * We will reset these values back later.
1535                          */
1536                         iarg->guid = this_guid;
1537                         iarg->poolname = NULL;
1538
1539                         /*
1540                          * We need to build up a cache of devices that exists
1541                          * in the paths pointed to by the cachefile. This allows
1542                          * us to preserve the device namespace that was
1543                          * originally specified by the user but also lets us
1544                          * scan devices in those directories in case they had
1545                          * been renamed.
1546                          */
1547                         pthread_mutex_init(&lock, NULL);
1548                         discover_cached_paths(hdl, nvroot, cache, &lock);
1549                         nvlist_t *nv = zpool_find_import_impl(hdl, iarg,
1550                             &lock, cache);
1551                         pthread_mutex_destroy(&lock);
1552
1553                         /*
1554                          * zpool_find_import_impl will return back
1555                          * a list of pools that it found based on the
1556                          * device cache. There should only be one pool
1557                          * since we're looking for a specific guid.
1558                          * We will use that pool to build up the final
1559                          * pool nvlist which is returned back to the
1560                          * caller.
1561                          */
1562                         nvpair_t *pair = nvlist_next_nvpair(nv, NULL);
1563                         fnvlist_add_nvlist(pools, nvpair_name(pair),
1564                             fnvpair_value_nvlist(pair));
1565
1566                         VERIFY3P(nvlist_next_nvpair(nv, pair), ==, NULL);
1567
1568                         iarg->guid = saved_guid;
1569                         iarg->poolname = saved_poolname;
1570                         continue;
1571                 }
1572
1573                 if (nvlist_add_string(src, ZPOOL_CONFIG_CACHEFILE,
1574                     iarg->cachefile) != 0) {
1575                         (void) zutil_no_memory(hdl);
1576                         nvlist_free(raw);
1577                         nvlist_free(pools);
1578                         return (NULL);
1579                 }
1580
1581                 if ((dst = zutil_refresh_config(hdl, src)) == NULL) {
1582                         nvlist_free(raw);
1583                         nvlist_free(pools);
1584                         return (NULL);
1585                 }
1586
1587                 if (nvlist_add_nvlist(pools, nvpair_name(elem), dst) != 0) {
1588                         (void) zutil_no_memory(hdl);
1589                         nvlist_free(dst);
1590                         nvlist_free(raw);
1591                         nvlist_free(pools);
1592                         return (NULL);
1593                 }
1594                 nvlist_free(dst);
1595         }
1596         nvlist_free(raw);
1597         return (pools);
1598 }
1599
1600 static nvlist_t *
1601 zpool_find_import(libpc_handle_t *hdl, importargs_t *iarg)
1602 {
1603         pthread_mutex_t lock;
1604         avl_tree_t *cache;
1605         nvlist_t *pools = NULL;
1606
1607         verify(iarg->poolname == NULL || iarg->guid == 0);
1608         pthread_mutex_init(&lock, NULL);
1609
1610         /*
1611          * Locate pool member vdevs by blkid or by directory scanning.
1612          * On success a newly allocated AVL tree which is populated with an
1613          * entry for each discovered vdev will be returned in the cache.
1614          * It's the caller's responsibility to consume and destroy this tree.
1615          */
1616         if (iarg->scan || iarg->paths != 0) {
1617                 size_t dirs = iarg->paths;
1618                 const char * const *dir = (const char * const *)iarg->path;
1619
1620                 if (dirs == 0)
1621                         dir = zpool_default_search_paths(&dirs);
1622
1623                 if (zpool_find_import_scan(hdl, &lock, &cache,
1624                     dir, dirs) != 0) {
1625                         pthread_mutex_destroy(&lock);
1626                         return (NULL);
1627                 }
1628         } else {
1629                 if (zpool_find_import_blkid(hdl, &lock, &cache) != 0) {
1630                         pthread_mutex_destroy(&lock);
1631                         return (NULL);
1632                 }
1633         }
1634
1635         pools = zpool_find_import_impl(hdl, iarg, &lock, cache);
1636         pthread_mutex_destroy(&lock);
1637         return (pools);
1638 }
1639
1640
1641 nvlist_t *
1642 zpool_search_import(void *hdl, importargs_t *import,
1643     const pool_config_ops_t *pco)
1644 {
1645         libpc_handle_t handle = { 0 };
1646         nvlist_t *pools = NULL;
1647
1648         handle.lpc_lib_handle = hdl;
1649         handle.lpc_ops = pco;
1650         handle.lpc_printerr = B_TRUE;
1651
1652         verify(import->poolname == NULL || import->guid == 0);
1653
1654         if (import->cachefile != NULL)
1655                 pools = zpool_find_import_cached(&handle, import);
1656         else
1657                 pools = zpool_find_import(&handle, import);
1658
1659         if ((pools == NULL || nvlist_empty(pools)) &&
1660             handle.lpc_open_access_error && geteuid() != 0) {
1661                 (void) zutil_error(&handle, EZFS_EACESS, dgettext(TEXT_DOMAIN,
1662                     "no pools found"));
1663         }
1664
1665         return (pools);
1666 }
1667
1668 static boolean_t
1669 pool_match(nvlist_t *cfg, char *tgt)
1670 {
1671         uint64_t v, guid = strtoull(tgt, NULL, 0);
1672         char *s;
1673
1674         if (guid != 0) {
1675                 if (nvlist_lookup_uint64(cfg, ZPOOL_CONFIG_POOL_GUID, &v) == 0)
1676                         return (v == guid);
1677         } else {
1678                 if (nvlist_lookup_string(cfg, ZPOOL_CONFIG_POOL_NAME, &s) == 0)
1679                         return (strcmp(s, tgt) == 0);
1680         }
1681         return (B_FALSE);
1682 }
1683
1684 int
1685 zpool_find_config(void *hdl, const char *target, nvlist_t **configp,
1686     importargs_t *args, const pool_config_ops_t *pco)
1687 {
1688         nvlist_t *pools;
1689         nvlist_t *match = NULL;
1690         nvlist_t *config = NULL;
1691         char *sepp = NULL;
1692         char sep = '\0';
1693         int count = 0;
1694         char *targetdup = strdup(target);
1695
1696         *configp = NULL;
1697
1698         if ((sepp = strpbrk(targetdup, "/@")) != NULL) {
1699                 sep = *sepp;
1700                 *sepp = '\0';
1701         }
1702
1703         pools = zpool_search_import(hdl, args, pco);
1704
1705         if (pools != NULL) {
1706                 nvpair_t *elem = NULL;
1707                 while ((elem = nvlist_next_nvpair(pools, elem)) != NULL) {
1708                         VERIFY0(nvpair_value_nvlist(elem, &config));
1709                         if (pool_match(config, targetdup)) {
1710                                 count++;
1711                                 if (match != NULL) {
1712                                         /* multiple matches found */
1713                                         continue;
1714                                 } else {
1715                                         match = fnvlist_dup(config);
1716                                 }
1717                         }
1718                 }
1719                 fnvlist_free(pools);
1720         }
1721
1722         if (count == 0) {
1723                 free(targetdup);
1724                 return (ENOENT);
1725         }
1726
1727         if (count > 1) {
1728                 free(targetdup);
1729                 fnvlist_free(match);
1730                 return (EINVAL);
1731         }
1732
1733         *configp = match;
1734         free(targetdup);
1735
1736         return (0);
1737 }