Fix gcc uninitialized variable warnings
[zfs.git] / 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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23  */
24
25 /*
26  * Pool import support functions.
27  *
28  * To import a pool, we rely on reading the configuration information from the
29  * ZFS label of each device.  If we successfully read the label, then we
30  * organize the configuration information in the following hierarchy:
31  *
32  *      pool guid -> toplevel vdev guid -> label txg
33  *
34  * Duplicate entries matching this same tuple will be discarded.  Once we have
35  * examined every device, we pick the best label txg config for each toplevel
36  * vdev.  We then arrange these toplevel vdevs into a complete pool config, and
37  * update any paths that have changed.  Finally, we attempt to import the pool
38  * using our derived config, and record the results.
39  */
40
41 #include <ctype.h>
42 #include <devid.h>
43 #include <dirent.h>
44 #include <errno.h>
45 #include <libintl.h>
46 #include <stddef.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <sys/stat.h>
50 #include <unistd.h>
51 #include <fcntl.h>
52 #include <sys/vtoc.h>
53 #include <sys/dktp/fdisk.h>
54 #include <sys/efi_partition.h>
55 #include <thread_pool.h>
56
57 #include <sys/vdev_impl.h>
58
59 #include "libzfs.h"
60 #include "libzfs_impl.h"
61
62 /*
63  * Intermediate structures used to gather configuration information.
64  */
65 typedef struct config_entry {
66         uint64_t                ce_txg;
67         nvlist_t                *ce_config;
68         struct config_entry     *ce_next;
69 } config_entry_t;
70
71 typedef struct vdev_entry {
72         uint64_t                ve_guid;
73         config_entry_t          *ve_configs;
74         struct vdev_entry       *ve_next;
75 } vdev_entry_t;
76
77 typedef struct pool_entry {
78         uint64_t                pe_guid;
79         vdev_entry_t            *pe_vdevs;
80         struct pool_entry       *pe_next;
81 } pool_entry_t;
82
83 typedef struct name_entry {
84         char                    *ne_name;
85         uint64_t                ne_guid;
86         struct name_entry       *ne_next;
87 } name_entry_t;
88
89 typedef struct pool_list {
90         pool_entry_t            *pools;
91         name_entry_t            *names;
92 } pool_list_t;
93
94 static char *
95 get_devid(const char *path)
96 {
97         int fd;
98         ddi_devid_t devid;
99         char *minor, *ret;
100
101         if ((fd = open(path, O_RDONLY)) < 0)
102                 return (NULL);
103
104         minor = NULL;
105         ret = NULL;
106         if (devid_get(fd, &devid) == 0) {
107                 if (devid_get_minor_name(fd, &minor) == 0)
108                         ret = devid_str_encode(devid, minor);
109                 if (minor != NULL)
110                         devid_str_free(minor);
111                 devid_free(devid);
112         }
113         (void) close(fd);
114
115         return (ret);
116 }
117
118
119 /*
120  * Go through and fix up any path and/or devid information for the given vdev
121  * configuration.
122  */
123 static int
124 fix_paths(nvlist_t *nv, name_entry_t *names)
125 {
126         nvlist_t **child;
127         uint_t c, children;
128         uint64_t guid;
129         name_entry_t *ne, *best;
130         char *path, *devid;
131         int matched;
132
133         if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
134             &child, &children) == 0) {
135                 for (c = 0; c < children; c++)
136                         if (fix_paths(child[c], names) != 0)
137                                 return (-1);
138                 return (0);
139         }
140
141         /*
142          * This is a leaf (file or disk) vdev.  In either case, go through
143          * the name list and see if we find a matching guid.  If so, replace
144          * the path and see if we can calculate a new devid.
145          *
146          * There may be multiple names associated with a particular guid, in
147          * which case we have overlapping slices or multiple paths to the same
148          * disk.  If this is the case, then we want to pick the path that is
149          * the most similar to the original, where "most similar" is the number
150          * of matching characters starting from the end of the path.  This will
151          * preserve slice numbers even if the disks have been reorganized, and
152          * will also catch preferred disk names if multiple paths exist.
153          */
154         verify(nvlist_lookup_uint64(nv, ZPOOL_CONFIG_GUID, &guid) == 0);
155         if (nvlist_lookup_string(nv, ZPOOL_CONFIG_PATH, &path) != 0)
156                 path = NULL;
157
158         matched = 0;
159         best = NULL;
160         for (ne = names; ne != NULL; ne = ne->ne_next) {
161                 if (ne->ne_guid == guid) {
162                         const char *src, *dst;
163                         int count;
164
165                         if (path == NULL) {
166                                 best = ne;
167                                 break;
168                         }
169
170                         src = ne->ne_name + strlen(ne->ne_name) - 1;
171                         dst = path + strlen(path) - 1;
172                         for (count = 0; src >= ne->ne_name && dst >= path;
173                             src--, dst--, count++)
174                                 if (*src != *dst)
175                                         break;
176
177                         /*
178                          * At this point, 'count' is the number of characters
179                          * matched from the end.
180                          */
181                         if (count > matched || best == NULL) {
182                                 best = ne;
183                                 matched = count;
184                         }
185                 }
186         }
187
188         if (best == NULL)
189                 return (0);
190
191         if (nvlist_add_string(nv, ZPOOL_CONFIG_PATH, best->ne_name) != 0)
192                 return (-1);
193
194         if ((devid = get_devid(best->ne_name)) == NULL) {
195                 (void) nvlist_remove_all(nv, ZPOOL_CONFIG_DEVID);
196         } else {
197                 if (nvlist_add_string(nv, ZPOOL_CONFIG_DEVID, devid) != 0)
198                         return (-1);
199                 devid_str_free(devid);
200         }
201
202         return (0);
203 }
204
205 /*
206  * Add the given configuration to the list of known devices.
207  */
208 static int
209 add_config(libzfs_handle_t *hdl, pool_list_t *pl, const char *path,
210     nvlist_t *config)
211 {
212         uint64_t pool_guid, vdev_guid, top_guid, txg, state;
213         pool_entry_t *pe;
214         vdev_entry_t *ve;
215         config_entry_t *ce;
216         name_entry_t *ne;
217
218         /*
219          * If this is a hot spare not currently in use or level 2 cache
220          * device, add it to the list of names to translate, but don't do
221          * anything else.
222          */
223         if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_STATE,
224             &state) == 0 &&
225             (state == POOL_STATE_SPARE || state == POOL_STATE_L2CACHE) &&
226             nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID, &vdev_guid) == 0) {
227                 if ((ne = zfs_alloc(hdl, sizeof (name_entry_t))) == NULL)
228                         return (-1);
229
230                 if ((ne->ne_name = zfs_strdup(hdl, path)) == NULL) {
231                         free(ne);
232                         return (-1);
233                 }
234                 ne->ne_guid = vdev_guid;
235                 ne->ne_next = pl->names;
236                 pl->names = ne;
237                 return (0);
238         }
239
240         /*
241          * If we have a valid config but cannot read any of these fields, then
242          * it means we have a half-initialized label.  In vdev_label_init()
243          * we write a label with txg == 0 so that we can identify the device
244          * in case the user refers to the same disk later on.  If we fail to
245          * create the pool, we'll be left with a label in this state
246          * which should not be considered part of a valid pool.
247          */
248         if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
249             &pool_guid) != 0 ||
250             nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID,
251             &vdev_guid) != 0 ||
252             nvlist_lookup_uint64(config, ZPOOL_CONFIG_TOP_GUID,
253             &top_guid) != 0 ||
254             nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_TXG,
255             &txg) != 0 || txg == 0) {
256                 nvlist_free(config);
257                 return (0);
258         }
259
260         /*
261          * First, see if we know about this pool.  If not, then add it to the
262          * list of known pools.
263          */
264         for (pe = pl->pools; pe != NULL; pe = pe->pe_next) {
265                 if (pe->pe_guid == pool_guid)
266                         break;
267         }
268
269         if (pe == NULL) {
270                 if ((pe = zfs_alloc(hdl, sizeof (pool_entry_t))) == NULL) {
271                         nvlist_free(config);
272                         return (-1);
273                 }
274                 pe->pe_guid = pool_guid;
275                 pe->pe_next = pl->pools;
276                 pl->pools = pe;
277         }
278
279         /*
280          * Second, see if we know about this toplevel vdev.  Add it if its
281          * missing.
282          */
283         for (ve = pe->pe_vdevs; ve != NULL; ve = ve->ve_next) {
284                 if (ve->ve_guid == top_guid)
285                         break;
286         }
287
288         if (ve == NULL) {
289                 if ((ve = zfs_alloc(hdl, sizeof (vdev_entry_t))) == NULL) {
290                         nvlist_free(config);
291                         return (-1);
292                 }
293                 ve->ve_guid = top_guid;
294                 ve->ve_next = pe->pe_vdevs;
295                 pe->pe_vdevs = ve;
296         }
297
298         /*
299          * Third, see if we have a config with a matching transaction group.  If
300          * so, then we do nothing.  Otherwise, add it to the list of known
301          * configs.
302          */
303         for (ce = ve->ve_configs; ce != NULL; ce = ce->ce_next) {
304                 if (ce->ce_txg == txg)
305                         break;
306         }
307
308         if (ce == NULL) {
309                 if ((ce = zfs_alloc(hdl, sizeof (config_entry_t))) == NULL) {
310                         nvlist_free(config);
311                         return (-1);
312                 }
313                 ce->ce_txg = txg;
314                 ce->ce_config = config;
315                 ce->ce_next = ve->ve_configs;
316                 ve->ve_configs = ce;
317         } else {
318                 nvlist_free(config);
319         }
320
321         /*
322          * At this point we've successfully added our config to the list of
323          * known configs.  The last thing to do is add the vdev guid -> path
324          * mappings so that we can fix up the configuration as necessary before
325          * doing the import.
326          */
327         if ((ne = zfs_alloc(hdl, sizeof (name_entry_t))) == NULL)
328                 return (-1);
329
330         if ((ne->ne_name = zfs_strdup(hdl, path)) == NULL) {
331                 free(ne);
332                 return (-1);
333         }
334
335         ne->ne_guid = vdev_guid;
336         ne->ne_next = pl->names;
337         pl->names = ne;
338
339         return (0);
340 }
341
342 /*
343  * Returns true if the named pool matches the given GUID.
344  */
345 static int
346 pool_active(libzfs_handle_t *hdl, const char *name, uint64_t guid,
347     boolean_t *isactive)
348 {
349         zpool_handle_t *zhp;
350         uint64_t theguid;
351
352         if (zpool_open_silent(hdl, name, &zhp) != 0)
353                 return (-1);
354
355         if (zhp == NULL) {
356                 *isactive = B_FALSE;
357                 return (0);
358         }
359
360         verify(nvlist_lookup_uint64(zhp->zpool_config, ZPOOL_CONFIG_POOL_GUID,
361             &theguid) == 0);
362
363         zpool_close(zhp);
364
365         *isactive = (theguid == guid);
366         return (0);
367 }
368
369 static nvlist_t *
370 refresh_config(libzfs_handle_t *hdl, nvlist_t *config)
371 {
372         nvlist_t *nvl;
373         zfs_cmd_t zc = { "\0", "\0", "\0", "\0", 0 };
374         int err;
375
376         if (zcmd_write_conf_nvlist(hdl, &zc, config) != 0)
377                 return (NULL);
378
379         if (zcmd_alloc_dst_nvlist(hdl, &zc,
380             zc.zc_nvlist_conf_size * 2) != 0) {
381                 zcmd_free_nvlists(&zc);
382                 return (NULL);
383         }
384
385         while ((err = ioctl(hdl->libzfs_fd, ZFS_IOC_POOL_TRYIMPORT,
386             &zc)) != 0 && errno == ENOMEM) {
387                 if (zcmd_expand_dst_nvlist(hdl, &zc) != 0) {
388                         zcmd_free_nvlists(&zc);
389                         return (NULL);
390                 }
391         }
392
393         if (err) {
394                 zcmd_free_nvlists(&zc);
395                 return (NULL);
396         }
397
398         if (zcmd_read_dst_nvlist(hdl, &zc, &nvl) != 0) {
399                 zcmd_free_nvlists(&zc);
400                 return (NULL);
401         }
402
403         zcmd_free_nvlists(&zc);
404         return (nvl);
405 }
406
407 /*
408  * Determine if the vdev id is a hole in the namespace.
409  */
410 boolean_t
411 vdev_is_hole(uint64_t *hole_array, uint_t holes, uint_t id)
412 {
413         int c;
414
415         for (c = 0; c < holes; c++) {
416
417                 /* Top-level is a hole */
418                 if (hole_array[c] == id)
419                         return (B_TRUE);
420         }
421         return (B_FALSE);
422 }
423
424 /*
425  * Convert our list of pools into the definitive set of configurations.  We
426  * start by picking the best config for each toplevel vdev.  Once that's done,
427  * we assemble the toplevel vdevs into a full config for the pool.  We make a
428  * pass to fix up any incorrect paths, and then add it to the main list to
429  * return to the user.
430  */
431 static nvlist_t *
432 get_configs(libzfs_handle_t *hdl, pool_list_t *pl, boolean_t active_ok)
433 {
434         pool_entry_t *pe;
435         vdev_entry_t *ve;
436         config_entry_t *ce;
437         nvlist_t *ret = NULL, *config = NULL, *tmp = NULL, *nvtop, *nvroot;
438         nvlist_t **spares, **l2cache;
439         uint_t i, nspares, nl2cache;
440         boolean_t config_seen;
441         uint64_t best_txg;
442         char *name, *hostname;
443         uint64_t version, guid;
444         uint_t children = 0;
445         nvlist_t **child = NULL;
446         uint_t holes;
447         uint64_t *hole_array, max_id;
448         uint_t c;
449         boolean_t isactive;
450         uint64_t hostid;
451         nvlist_t *nvl;
452         boolean_t found_one = B_FALSE;
453         boolean_t valid_top_config = B_FALSE;
454
455         if (nvlist_alloc(&ret, 0, 0) != 0)
456                 goto nomem;
457
458         for (pe = pl->pools; pe != NULL; pe = pe->pe_next) {
459                 uint64_t id, max_txg = 0;
460
461                 if (nvlist_alloc(&config, NV_UNIQUE_NAME, 0) != 0)
462                         goto nomem;
463                 config_seen = B_FALSE;
464
465                 /*
466                  * Iterate over all toplevel vdevs.  Grab the pool configuration
467                  * from the first one we find, and then go through the rest and
468                  * add them as necessary to the 'vdevs' member of the config.
469                  */
470                 for (ve = pe->pe_vdevs; ve != NULL; ve = ve->ve_next) {
471
472                         /*
473                          * Determine the best configuration for this vdev by
474                          * selecting the config with the latest transaction
475                          * group.
476                          */
477                         best_txg = 0;
478                         for (ce = ve->ve_configs; ce != NULL;
479                             ce = ce->ce_next) {
480
481                                 if (ce->ce_txg > best_txg) {
482                                         tmp = ce->ce_config;
483                                         best_txg = ce->ce_txg;
484                                 }
485                         }
486
487                         /*
488                          * We rely on the fact that the max txg for the
489                          * pool will contain the most up-to-date information
490                          * about the valid top-levels in the vdev namespace.
491                          */
492                         if (best_txg > max_txg) {
493                                 (void) nvlist_remove(config,
494                                     ZPOOL_CONFIG_VDEV_CHILDREN,
495                                     DATA_TYPE_UINT64);
496                                 (void) nvlist_remove(config,
497                                     ZPOOL_CONFIG_HOLE_ARRAY,
498                                     DATA_TYPE_UINT64_ARRAY);
499
500                                 max_txg = best_txg;
501                                 hole_array = NULL;
502                                 holes = 0;
503                                 max_id = 0;
504                                 valid_top_config = B_FALSE;
505
506                                 if (nvlist_lookup_uint64(tmp,
507                                     ZPOOL_CONFIG_VDEV_CHILDREN, &max_id) == 0) {
508                                         verify(nvlist_add_uint64(config,
509                                             ZPOOL_CONFIG_VDEV_CHILDREN,
510                                             max_id) == 0);
511                                         valid_top_config = B_TRUE;
512                                 }
513
514                                 if (nvlist_lookup_uint64_array(tmp,
515                                     ZPOOL_CONFIG_HOLE_ARRAY, &hole_array,
516                                     &holes) == 0) {
517                                         verify(nvlist_add_uint64_array(config,
518                                             ZPOOL_CONFIG_HOLE_ARRAY,
519                                             hole_array, holes) == 0);
520                                 }
521                         }
522
523                         if (!config_seen) {
524                                 /*
525                                  * Copy the relevant pieces of data to the pool
526                                  * configuration:
527                                  *
528                                  *      version
529                                  *      pool guid
530                                  *      name
531                                  *      pool state
532                                  *      hostid (if available)
533                                  *      hostname (if available)
534                                  */
535                                 uint64_t state;
536
537                                 verify(nvlist_lookup_uint64(tmp,
538                                     ZPOOL_CONFIG_VERSION, &version) == 0);
539                                 if (nvlist_add_uint64(config,
540                                     ZPOOL_CONFIG_VERSION, version) != 0)
541                                         goto nomem;
542                                 verify(nvlist_lookup_uint64(tmp,
543                                     ZPOOL_CONFIG_POOL_GUID, &guid) == 0);
544                                 if (nvlist_add_uint64(config,
545                                     ZPOOL_CONFIG_POOL_GUID, guid) != 0)
546                                         goto nomem;
547                                 verify(nvlist_lookup_string(tmp,
548                                     ZPOOL_CONFIG_POOL_NAME, &name) == 0);
549                                 if (nvlist_add_string(config,
550                                     ZPOOL_CONFIG_POOL_NAME, name) != 0)
551                                         goto nomem;
552                                 verify(nvlist_lookup_uint64(tmp,
553                                     ZPOOL_CONFIG_POOL_STATE, &state) == 0);
554                                 if (nvlist_add_uint64(config,
555                                     ZPOOL_CONFIG_POOL_STATE, state) != 0)
556                                         goto nomem;
557                                 hostid = 0;
558                                 if (nvlist_lookup_uint64(tmp,
559                                     ZPOOL_CONFIG_HOSTID, &hostid) == 0) {
560                                         if (nvlist_add_uint64(config,
561                                             ZPOOL_CONFIG_HOSTID, hostid) != 0)
562                                                 goto nomem;
563                                         verify(nvlist_lookup_string(tmp,
564                                             ZPOOL_CONFIG_HOSTNAME,
565                                             &hostname) == 0);
566                                         if (nvlist_add_string(config,
567                                             ZPOOL_CONFIG_HOSTNAME,
568                                             hostname) != 0)
569                                                 goto nomem;
570                                 }
571
572                                 config_seen = B_TRUE;
573                         }
574
575                         /*
576                          * Add this top-level vdev to the child array.
577                          */
578                         verify(nvlist_lookup_nvlist(tmp,
579                             ZPOOL_CONFIG_VDEV_TREE, &nvtop) == 0);
580                         verify(nvlist_lookup_uint64(nvtop, ZPOOL_CONFIG_ID,
581                             &id) == 0);
582
583                         if (id >= children) {
584                                 nvlist_t **newchild;
585
586                                 newchild = zfs_alloc(hdl, (id + 1) *
587                                     sizeof (nvlist_t *));
588                                 if (newchild == NULL)
589                                         goto nomem;
590
591                                 for (c = 0; c < children; c++)
592                                         newchild[c] = child[c];
593
594                                 free(child);
595                                 child = newchild;
596                                 children = id + 1;
597                         }
598                         if (nvlist_dup(nvtop, &child[id], 0) != 0)
599                                 goto nomem;
600
601                 }
602
603                 /*
604                  * If we have information about all the top-levels then
605                  * clean up the nvlist which we've constructed. This
606                  * means removing any extraneous devices that are
607                  * beyond the valid range or adding devices to the end
608                  * of our array which appear to be missing.
609                  */
610                 if (valid_top_config) {
611                         if (max_id < children) {
612                                 for (c = max_id; c < children; c++)
613                                         nvlist_free(child[c]);
614                                 children = max_id;
615                         } else if (max_id > children) {
616                                 nvlist_t **newchild;
617
618                                 newchild = zfs_alloc(hdl, (max_id) *
619                                     sizeof (nvlist_t *));
620                                 if (newchild == NULL)
621                                         goto nomem;
622
623                                 for (c = 0; c < children; c++)
624                                         newchild[c] = child[c];
625
626                                 free(child);
627                                 child = newchild;
628                                 children = max_id;
629                         }
630                 }
631
632                 verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
633                     &guid) == 0);
634
635                 /*
636                  * The vdev namespace may contain holes as a result of
637                  * device removal. We must add them back into the vdev
638                  * tree before we process any missing devices.
639                  */
640                 if (holes > 0) {
641                         ASSERT(valid_top_config);
642
643                         for (c = 0; c < children; c++) {
644                                 nvlist_t *holey;
645
646                                 if (child[c] != NULL ||
647                                     !vdev_is_hole(hole_array, holes, c))
648                                         continue;
649
650                                 if (nvlist_alloc(&holey, NV_UNIQUE_NAME,
651                                     0) != 0)
652                                         goto nomem;
653
654                                 /*
655                                  * Holes in the namespace are treated as
656                                  * "hole" top-level vdevs and have a
657                                  * special flag set on them.
658                                  */
659                                 if (nvlist_add_string(holey,
660                                     ZPOOL_CONFIG_TYPE,
661                                     VDEV_TYPE_HOLE) != 0 ||
662                                     nvlist_add_uint64(holey,
663                                     ZPOOL_CONFIG_ID, c) != 0 ||
664                                     nvlist_add_uint64(holey,
665                                     ZPOOL_CONFIG_GUID, 0ULL) != 0)
666                                         goto nomem;
667                                 child[c] = holey;
668                         }
669                 }
670
671                 /*
672                  * Look for any missing top-level vdevs.  If this is the case,
673                  * create a faked up 'missing' vdev as a placeholder.  We cannot
674                  * simply compress the child array, because the kernel performs
675                  * certain checks to make sure the vdev IDs match their location
676                  * in the configuration.
677                  */
678                 for (c = 0; c < children; c++) {
679                         if (child[c] == NULL) {
680                                 nvlist_t *missing;
681                                 if (nvlist_alloc(&missing, NV_UNIQUE_NAME,
682                                     0) != 0)
683                                         goto nomem;
684                                 if (nvlist_add_string(missing,
685                                     ZPOOL_CONFIG_TYPE,
686                                     VDEV_TYPE_MISSING) != 0 ||
687                                     nvlist_add_uint64(missing,
688                                     ZPOOL_CONFIG_ID, c) != 0 ||
689                                     nvlist_add_uint64(missing,
690                                     ZPOOL_CONFIG_GUID, 0ULL) != 0) {
691                                         nvlist_free(missing);
692                                         goto nomem;
693                                 }
694                                 child[c] = missing;
695                         }
696                 }
697
698                 /*
699                  * Put all of this pool's top-level vdevs into a root vdev.
700                  */
701                 if (nvlist_alloc(&nvroot, NV_UNIQUE_NAME, 0) != 0)
702                         goto nomem;
703                 if (nvlist_add_string(nvroot, ZPOOL_CONFIG_TYPE,
704                     VDEV_TYPE_ROOT) != 0 ||
705                     nvlist_add_uint64(nvroot, ZPOOL_CONFIG_ID, 0ULL) != 0 ||
706                     nvlist_add_uint64(nvroot, ZPOOL_CONFIG_GUID, guid) != 0 ||
707                     nvlist_add_nvlist_array(nvroot, ZPOOL_CONFIG_CHILDREN,
708                     child, children) != 0) {
709                         nvlist_free(nvroot);
710                         goto nomem;
711                 }
712
713                 for (c = 0; c < children; c++)
714                         nvlist_free(child[c]);
715                 free(child);
716                 children = 0;
717                 child = NULL;
718
719                 /*
720                  * Go through and fix up any paths and/or devids based on our
721                  * known list of vdev GUID -> path mappings.
722                  */
723                 if (fix_paths(nvroot, pl->names) != 0) {
724                         nvlist_free(nvroot);
725                         goto nomem;
726                 }
727
728                 /*
729                  * Add the root vdev to this pool's configuration.
730                  */
731                 if (nvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
732                     nvroot) != 0) {
733                         nvlist_free(nvroot);
734                         goto nomem;
735                 }
736                 nvlist_free(nvroot);
737
738                 /*
739                  * zdb uses this path to report on active pools that were
740                  * imported or created using -R.
741                  */
742                 if (active_ok)
743                         goto add_pool;
744
745                 /*
746                  * Determine if this pool is currently active, in which case we
747                  * can't actually import it.
748                  */
749                 verify(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
750                     &name) == 0);
751                 verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
752                     &guid) == 0);
753
754                 if (pool_active(hdl, name, guid, &isactive) != 0)
755                         goto error;
756
757                 if (isactive) {
758                         nvlist_free(config);
759                         config = NULL;
760                         continue;
761                 }
762
763                 if ((nvl = refresh_config(hdl, config)) == NULL) {
764                         nvlist_free(config);
765                         config = NULL;
766                         continue;
767                 }
768
769                 nvlist_free(config);
770                 config = nvl;
771
772                 /*
773                  * Go through and update the paths for spares, now that we have
774                  * them.
775                  */
776                 verify(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
777                     &nvroot) == 0);
778                 if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES,
779                     &spares, &nspares) == 0) {
780                         for (i = 0; i < nspares; i++) {
781                                 if (fix_paths(spares[i], pl->names) != 0)
782                                         goto nomem;
783                         }
784                 }
785
786                 /*
787                  * Update the paths for l2cache devices.
788                  */
789                 if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_L2CACHE,
790                     &l2cache, &nl2cache) == 0) {
791                         for (i = 0; i < nl2cache; i++) {
792                                 if (fix_paths(l2cache[i], pl->names) != 0)
793                                         goto nomem;
794                         }
795                 }
796
797                 /*
798                  * Restore the original information read from the actual label.
799                  */
800                 (void) nvlist_remove(config, ZPOOL_CONFIG_HOSTID,
801                     DATA_TYPE_UINT64);
802                 (void) nvlist_remove(config, ZPOOL_CONFIG_HOSTNAME,
803                     DATA_TYPE_STRING);
804                 if (hostid != 0) {
805                         verify(nvlist_add_uint64(config, ZPOOL_CONFIG_HOSTID,
806                             hostid) == 0);
807                         verify(nvlist_add_string(config, ZPOOL_CONFIG_HOSTNAME,
808                             hostname) == 0);
809                 }
810
811 add_pool:
812                 /*
813                  * Add this pool to the list of configs.
814                  */
815                 verify(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
816                     &name) == 0);
817                 if (nvlist_add_nvlist(ret, name, config) != 0)
818                         goto nomem;
819
820                 found_one = B_TRUE;
821                 nvlist_free(config);
822                 config = NULL;
823         }
824
825         if (!found_one) {
826                 nvlist_free(ret);
827                 ret = NULL;
828         }
829
830         return (ret);
831
832 nomem:
833         (void) no_memory(hdl);
834 error:
835         nvlist_free(config);
836         nvlist_free(ret);
837         for (c = 0; c < children; c++)
838                 nvlist_free(child[c]);
839         free(child);
840
841         return (NULL);
842 }
843
844 /*
845  * Return the offset of the given label.
846  */
847 static uint64_t
848 label_offset(uint64_t size, int l)
849 {
850         ASSERT(P2PHASE_TYPED(size, sizeof (vdev_label_t), uint64_t) == 0);
851         return (l * sizeof (vdev_label_t) + (l < VDEV_LABELS / 2 ?
852             0 : size - VDEV_LABELS * sizeof (vdev_label_t)));
853 }
854
855 /*
856  * Given a file descriptor, read the label information and return an nvlist
857  * describing the configuration, if there is one.
858  */
859 int
860 zpool_read_label(int fd, nvlist_t **config)
861 {
862         struct stat64 statbuf;
863         int l;
864         vdev_label_t *label;
865         uint64_t state, txg, size;
866
867         *config = NULL;
868
869         if (fstat64(fd, &statbuf) == -1)
870                 return (0);
871         size = P2ALIGN_TYPED(statbuf.st_size, sizeof (vdev_label_t), uint64_t);
872
873         if ((label = malloc(sizeof (vdev_label_t))) == NULL)
874                 return (-1);
875
876         for (l = 0; l < VDEV_LABELS; l++) {
877                 if (pread64(fd, label, sizeof (vdev_label_t),
878                     label_offset(size, l)) != sizeof (vdev_label_t))
879                         continue;
880
881                 if (nvlist_unpack(label->vl_vdev_phys.vp_nvlist,
882                     sizeof (label->vl_vdev_phys.vp_nvlist), config, 0) != 0)
883                         continue;
884
885                 if (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_STATE,
886                     &state) != 0 || state > POOL_STATE_L2CACHE) {
887                         nvlist_free(*config);
888                         continue;
889                 }
890
891                 if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE &&
892                     (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_TXG,
893                     &txg) != 0 || txg == 0)) {
894                         nvlist_free(*config);
895                         continue;
896                 }
897
898                 free(label);
899                 return (0);
900         }
901
902         free(label);
903         *config = NULL;
904         return (0);
905 }
906
907 typedef struct rdsk_node {
908         char *rn_name;
909         int rn_dfd;
910         libzfs_handle_t *rn_hdl;
911         nvlist_t *rn_config;
912         avl_tree_t *rn_avl;
913         avl_node_t rn_node;
914         boolean_t rn_nozpool;
915 } rdsk_node_t;
916
917 static int
918 slice_cache_compare(const void *arg1, const void *arg2)
919 {
920         const char  *nm1 = ((rdsk_node_t *)arg1)->rn_name;
921         const char  *nm2 = ((rdsk_node_t *)arg2)->rn_name;
922         char *nm1slice, *nm2slice;
923         int rv;
924
925         /*
926          * slices zero and two are the most likely to provide results,
927          * so put those first
928          */
929         nm1slice = strstr(nm1, "s0");
930         nm2slice = strstr(nm2, "s0");
931         if (nm1slice && !nm2slice) {
932                 return (-1);
933         }
934         if (!nm1slice && nm2slice) {
935                 return (1);
936         }
937         nm1slice = strstr(nm1, "s2");
938         nm2slice = strstr(nm2, "s2");
939         if (nm1slice && !nm2slice) {
940                 return (-1);
941         }
942         if (!nm1slice && nm2slice) {
943                 return (1);
944         }
945
946         rv = strcmp(nm1, nm2);
947         if (rv == 0)
948                 return (0);
949         return (rv > 0 ? 1 : -1);
950 }
951
952 static void
953 check_one_slice(avl_tree_t *r, char *diskname, uint_t partno,
954     diskaddr_t size, uint_t blksz)
955 {
956         rdsk_node_t tmpnode;
957         rdsk_node_t *node;
958         char sname[MAXNAMELEN];
959
960         tmpnode.rn_name = &sname[0];
961         (void) snprintf(tmpnode.rn_name, MAXNAMELEN, "%s%u",
962             diskname, partno);
963         /*
964          * protect against division by zero for disk labels that
965          * contain a bogus sector size
966          */
967         if (blksz == 0)
968                 blksz = DEV_BSIZE;
969         /* too small to contain a zpool? */
970         if ((size < (SPA_MINDEVSIZE / blksz)) &&
971             (node = avl_find(r, &tmpnode, NULL)))
972                 node->rn_nozpool = B_TRUE;
973 }
974
975 static void
976 nozpool_all_slices(avl_tree_t *r, const char *sname)
977 {
978         char diskname[MAXNAMELEN];
979         char *ptr;
980         int i;
981
982         (void) strncpy(diskname, sname, MAXNAMELEN);
983         if (((ptr = strrchr(diskname, 's')) == NULL) &&
984             ((ptr = strrchr(diskname, 'p')) == NULL))
985                 return;
986         ptr[0] = 's';
987         ptr[1] = '\0';
988         for (i = 0; i < NDKMAP; i++)
989                 check_one_slice(r, diskname, i, 0, 1);
990         ptr[0] = 'p';
991         for (i = 0; i <= FD_NUMPART; i++)
992                 check_one_slice(r, diskname, i, 0, 1);
993 }
994
995 static void
996 check_slices(avl_tree_t *r, int fd, const char *sname)
997 {
998         struct extvtoc vtoc;
999         struct dk_gpt *gpt;
1000         char diskname[MAXNAMELEN];
1001         char *ptr;
1002         int i;
1003
1004         (void) strncpy(diskname, sname, MAXNAMELEN);
1005         if ((ptr = strrchr(diskname, 's')) == NULL || !isdigit(ptr[1]))
1006                 return;
1007         ptr[1] = '\0';
1008
1009         if (read_extvtoc(fd, &vtoc) >= 0) {
1010                 for (i = 0; i < NDKMAP; i++)
1011                         check_one_slice(r, diskname, i,
1012                             vtoc.v_part[i].p_size, vtoc.v_sectorsz);
1013         } else if (efi_alloc_and_read(fd, &gpt) >= 0) {
1014                 /*
1015                  * on x86 we'll still have leftover links that point
1016                  * to slices s[9-15], so use NDKMAP instead
1017                  */
1018                 for (i = 0; i < NDKMAP; i++)
1019                         check_one_slice(r, diskname, i,
1020                             gpt->efi_parts[i].p_size, gpt->efi_lbasize);
1021                 /* nodes p[1-4] are never used with EFI labels */
1022                 ptr[0] = 'p';
1023                 for (i = 1; i <= FD_NUMPART; i++)
1024                         check_one_slice(r, diskname, i, 0, 1);
1025                 efi_free(gpt);
1026         }
1027 }
1028
1029 static void
1030 zpool_open_func(void *arg)
1031 {
1032         rdsk_node_t *rn = arg;
1033         struct stat64 statbuf;
1034         nvlist_t *config;
1035         int fd;
1036
1037         if (rn->rn_nozpool)
1038                 return;
1039         if ((fd = openat64(rn->rn_dfd, rn->rn_name, O_RDONLY)) < 0) {
1040                 /* symlink to a device that's no longer there */
1041                 if (errno == ENOENT)
1042                         nozpool_all_slices(rn->rn_avl, rn->rn_name);
1043                 return;
1044         }
1045         /*
1046          * Ignore failed stats.  We only want regular
1047          * files, character devs and block devs.
1048          */
1049         if (fstat64(fd, &statbuf) != 0 ||
1050             (!S_ISREG(statbuf.st_mode) &&
1051             !S_ISCHR(statbuf.st_mode) &&
1052             !S_ISBLK(statbuf.st_mode))) {
1053                 (void) close(fd);
1054                 return;
1055         }
1056         /* this file is too small to hold a zpool */
1057         if (S_ISREG(statbuf.st_mode) &&
1058             statbuf.st_size < SPA_MINDEVSIZE) {
1059                 (void) close(fd);
1060                 return;
1061         } else if (!S_ISREG(statbuf.st_mode)) {
1062                 /*
1063                  * Try to read the disk label first so we don't have to
1064                  * open a bunch of minor nodes that can't have a zpool.
1065                  */
1066                 check_slices(rn->rn_avl, fd, rn->rn_name);
1067         }
1068
1069         if ((zpool_read_label(fd, &config)) != 0) {
1070                 (void) close(fd);
1071                 (void) no_memory(rn->rn_hdl);
1072                 return;
1073         }
1074         (void) close(fd);
1075
1076
1077         rn->rn_config = config;
1078         if (config != NULL) {
1079                 assert(rn->rn_nozpool == B_FALSE);
1080         }
1081 }
1082
1083 /*
1084  * Given a file descriptor, clear (zero) the label information.  This function
1085  * is currently only used in the appliance stack as part of the ZFS sysevent
1086  * module.
1087  */
1088 int
1089 zpool_clear_label(int fd)
1090 {
1091         struct stat64 statbuf;
1092         int l;
1093         vdev_label_t *label;
1094         uint64_t size;
1095
1096         if (fstat64(fd, &statbuf) == -1)
1097                 return (0);
1098         size = P2ALIGN_TYPED(statbuf.st_size, sizeof (vdev_label_t), uint64_t);
1099
1100         if ((label = calloc(sizeof (vdev_label_t), 1)) == NULL)
1101                 return (-1);
1102
1103         for (l = 0; l < VDEV_LABELS; l++) {
1104                 if (pwrite64(fd, label, sizeof (vdev_label_t),
1105                     label_offset(size, l)) != sizeof (vdev_label_t))
1106                         return (-1);
1107         }
1108
1109         free(label);
1110         return (0);
1111 }
1112
1113 /*
1114  * Given a list of directories to search, find all pools stored on disk.  This
1115  * includes partial pools which are not available to import.  If no args are
1116  * given (argc is 0), then the default directory (/dev/dsk) is searched.
1117  * poolname or guid (but not both) are provided by the caller when trying
1118  * to import a specific pool.
1119  */
1120 static nvlist_t *
1121 zpool_find_import_impl(libzfs_handle_t *hdl, importargs_t *iarg)
1122 {
1123         int i, dirs = iarg->paths;
1124         DIR *dirp = NULL;
1125         struct dirent64 *dp;
1126         char path[MAXPATHLEN];
1127         char *end, **dir = iarg->path;
1128         size_t pathleft;
1129         nvlist_t *ret = NULL;
1130         static char *default_dir = "/dev/dsk";
1131         pool_list_t pools = { 0 };
1132         pool_entry_t *pe, *penext;
1133         vdev_entry_t *ve, *venext;
1134         config_entry_t *ce, *cenext;
1135         name_entry_t *ne, *nenext;
1136         avl_tree_t slice_cache;
1137         rdsk_node_t *slice;
1138         void *cookie;
1139
1140         if (dirs == 0) {
1141                 dirs = 1;
1142                 dir = &default_dir;
1143         }
1144
1145         /*
1146          * Go through and read the label configuration information from every
1147          * possible device, organizing the information according to pool GUID
1148          * and toplevel GUID.
1149          */
1150         for (i = 0; i < dirs; i++) {
1151                 tpool_t *t;
1152                 char *rdsk;
1153                 int dfd;
1154
1155                 /* use realpath to normalize the path */
1156                 if (realpath(dir[i], path) == 0) {
1157                         (void) zfs_error_fmt(hdl, EZFS_BADPATH,
1158                             dgettext(TEXT_DOMAIN, "cannot open '%s'"), dir[i]);
1159                         goto error;
1160                 }
1161                 end = &path[strlen(path)];
1162                 *end++ = '/';
1163                 *end = 0;
1164                 pathleft = &path[sizeof (path)] - end;
1165
1166                 /*
1167                  * Using raw devices instead of block devices when we're
1168                  * reading the labels skips a bunch of slow operations during
1169                  * close(2) processing, so we replace /dev/dsk with /dev/rdsk.
1170                  */
1171                 if (strcmp(path, "/dev/dsk/") == 0)
1172                         rdsk = "/dev/rdsk/";
1173                 else
1174                         rdsk = path;
1175
1176                 if ((dfd = open64(rdsk, O_RDONLY)) < 0 ||
1177                     (dirp = fdopendir(dfd)) == NULL) {
1178                         zfs_error_aux(hdl, strerror(errno));
1179                         (void) zfs_error_fmt(hdl, EZFS_BADPATH,
1180                             dgettext(TEXT_DOMAIN, "cannot open '%s'"),
1181                             rdsk);
1182                         goto error;
1183                 }
1184
1185                 avl_create(&slice_cache, slice_cache_compare,
1186                     sizeof (rdsk_node_t), offsetof(rdsk_node_t, rn_node));
1187                 /*
1188                  * This is not MT-safe, but we have no MT consumers of libzfs
1189                  */
1190                 while ((dp = readdir64(dirp)) != NULL) {
1191                         const char *name = dp->d_name;
1192                         if (name[0] == '.' &&
1193                             (name[1] == 0 || (name[1] == '.' && name[2] == 0)))
1194                                 continue;
1195
1196                         slice = zfs_alloc(hdl, sizeof (rdsk_node_t));
1197                         slice->rn_name = zfs_strdup(hdl, name);
1198                         slice->rn_avl = &slice_cache;
1199                         slice->rn_dfd = dfd;
1200                         slice->rn_hdl = hdl;
1201                         slice->rn_nozpool = B_FALSE;
1202                         avl_add(&slice_cache, slice);
1203                 }
1204                 /*
1205                  * create a thread pool to do all of this in parallel;
1206                  * rn_nozpool is not protected, so this is racy in that
1207                  * multiple tasks could decide that the same slice can
1208                  * not hold a zpool, which is benign.  Also choose
1209                  * double the number of processors; we hold a lot of
1210                  * locks in the kernel, so going beyond this doesn't
1211                  * buy us much.
1212                  */
1213                 t = tpool_create(1, 2 * sysconf(_SC_NPROCESSORS_ONLN),
1214                     0, NULL);
1215                 for (slice = avl_first(&slice_cache); slice;
1216                     (slice = avl_walk(&slice_cache, slice,
1217                     AVL_AFTER)))
1218                         (void) tpool_dispatch(t, zpool_open_func, slice);
1219                 tpool_wait(t);
1220                 tpool_destroy(t);
1221
1222                 cookie = NULL;
1223                 while ((slice = avl_destroy_nodes(&slice_cache,
1224                     &cookie)) != NULL) {
1225                         if (slice->rn_config != NULL) {
1226                                 nvlist_t *config = slice->rn_config;
1227                                 boolean_t matched = B_TRUE;
1228
1229                                 if (iarg->poolname != NULL) {
1230                                         char *pname;
1231
1232                                         matched = nvlist_lookup_string(config,
1233                                             ZPOOL_CONFIG_POOL_NAME,
1234                                             &pname) == 0 &&
1235                                             strcmp(iarg->poolname, pname) == 0;
1236                                 } else if (iarg->guid != 0) {
1237                                         uint64_t this_guid;
1238
1239                                         matched = nvlist_lookup_uint64(config,
1240                                             ZPOOL_CONFIG_POOL_GUID,
1241                                             &this_guid) == 0 &&
1242                                             iarg->guid == this_guid;
1243                                 }
1244                                 if (!matched) {
1245                                         nvlist_free(config);
1246                                         config = NULL;
1247                                         continue;
1248                                 }
1249                                 /* use the non-raw path for the config */
1250                                 (void) strlcpy(end, slice->rn_name, pathleft);
1251                                 if (add_config(hdl, &pools, path, config) != 0)
1252                                         goto error;
1253                         }
1254                         free(slice->rn_name);
1255                         free(slice);
1256                 }
1257                 avl_destroy(&slice_cache);
1258
1259                 (void) closedir(dirp);
1260                 dirp = NULL;
1261         }
1262
1263         ret = get_configs(hdl, &pools, iarg->can_be_active);
1264
1265 error:
1266         for (pe = pools.pools; pe != NULL; pe = penext) {
1267                 penext = pe->pe_next;
1268                 for (ve = pe->pe_vdevs; ve != NULL; ve = venext) {
1269                         venext = ve->ve_next;
1270                         for (ce = ve->ve_configs; ce != NULL; ce = cenext) {
1271                                 cenext = ce->ce_next;
1272                                 if (ce->ce_config)
1273                                         nvlist_free(ce->ce_config);
1274                                 free(ce);
1275                         }
1276                         free(ve);
1277                 }
1278                 free(pe);
1279         }
1280
1281         for (ne = pools.names; ne != NULL; ne = nenext) {
1282                 nenext = ne->ne_next;
1283                 if (ne->ne_name)
1284                         free(ne->ne_name);
1285                 free(ne);
1286         }
1287
1288         if (dirp)
1289                 (void) closedir(dirp);
1290
1291         return (ret);
1292 }
1293
1294 nvlist_t *
1295 zpool_find_import(libzfs_handle_t *hdl, int argc, char **argv)
1296 {
1297         importargs_t iarg = { 0 };
1298
1299         iarg.paths = argc;
1300         iarg.path = argv;
1301
1302         return (zpool_find_import_impl(hdl, &iarg));
1303 }
1304
1305 /*
1306  * Given a cache file, return the contents as a list of importable pools.
1307  * poolname or guid (but not both) are provided by the caller when trying
1308  * to import a specific pool.
1309  */
1310 nvlist_t *
1311 zpool_find_import_cached(libzfs_handle_t *hdl, const char *cachefile,
1312     char *poolname, uint64_t guid)
1313 {
1314         char *buf;
1315         int fd;
1316         struct stat64 statbuf;
1317         nvlist_t *raw, *src, *dst;
1318         nvlist_t *pools;
1319         nvpair_t *elem;
1320         char *name;
1321         uint64_t this_guid;
1322         boolean_t active;
1323
1324         verify(poolname == NULL || guid == 0);
1325
1326         if ((fd = open(cachefile, O_RDONLY)) < 0) {
1327                 zfs_error_aux(hdl, "%s", strerror(errno));
1328                 (void) zfs_error(hdl, EZFS_BADCACHE,
1329                     dgettext(TEXT_DOMAIN, "failed to open cache file"));
1330                 return (NULL);
1331         }
1332
1333         if (fstat64(fd, &statbuf) != 0) {
1334                 zfs_error_aux(hdl, "%s", strerror(errno));
1335                 (void) close(fd);
1336                 (void) zfs_error(hdl, EZFS_BADCACHE,
1337                     dgettext(TEXT_DOMAIN, "failed to get size of cache file"));
1338                 return (NULL);
1339         }
1340
1341         if ((buf = zfs_alloc(hdl, statbuf.st_size)) == NULL) {
1342                 (void) close(fd);
1343                 return (NULL);
1344         }
1345
1346         if (read(fd, buf, statbuf.st_size) != statbuf.st_size) {
1347                 (void) close(fd);
1348                 free(buf);
1349                 (void) zfs_error(hdl, EZFS_BADCACHE,
1350                     dgettext(TEXT_DOMAIN,
1351                     "failed to read cache file contents"));
1352                 return (NULL);
1353         }
1354
1355         (void) close(fd);
1356
1357         if (nvlist_unpack(buf, statbuf.st_size, &raw, 0) != 0) {
1358                 free(buf);
1359                 (void) zfs_error(hdl, EZFS_BADCACHE,
1360                     dgettext(TEXT_DOMAIN,
1361                     "invalid or corrupt cache file contents"));
1362                 return (NULL);
1363         }
1364
1365         free(buf);
1366
1367         /*
1368          * Go through and get the current state of the pools and refresh their
1369          * state.
1370          */
1371         if (nvlist_alloc(&pools, 0, 0) != 0) {
1372                 (void) no_memory(hdl);
1373                 nvlist_free(raw);
1374                 return (NULL);
1375         }
1376
1377         elem = NULL;
1378         while ((elem = nvlist_next_nvpair(raw, elem)) != NULL) {
1379                 verify(nvpair_value_nvlist(elem, &src) == 0);
1380
1381                 verify(nvlist_lookup_string(src, ZPOOL_CONFIG_POOL_NAME,
1382                     &name) == 0);
1383                 if (poolname != NULL && strcmp(poolname, name) != 0)
1384                         continue;
1385
1386                 verify(nvlist_lookup_uint64(src, ZPOOL_CONFIG_POOL_GUID,
1387                     &this_guid) == 0);
1388                 if (guid != 0) {
1389                         verify(nvlist_lookup_uint64(src, ZPOOL_CONFIG_POOL_GUID,
1390                             &this_guid) == 0);
1391                         if (guid != this_guid)
1392                                 continue;
1393                 }
1394
1395                 if (pool_active(hdl, name, this_guid, &active) != 0) {
1396                         nvlist_free(raw);
1397                         nvlist_free(pools);
1398                         return (NULL);
1399                 }
1400
1401                 if (active)
1402                         continue;
1403
1404                 if ((dst = refresh_config(hdl, src)) == NULL) {
1405                         nvlist_free(raw);
1406                         nvlist_free(pools);
1407                         return (NULL);
1408                 }
1409
1410                 if (nvlist_add_nvlist(pools, nvpair_name(elem), dst) != 0) {
1411                         (void) no_memory(hdl);
1412                         nvlist_free(dst);
1413                         nvlist_free(raw);
1414                         nvlist_free(pools);
1415                         return (NULL);
1416                 }
1417                 nvlist_free(dst);
1418         }
1419
1420         nvlist_free(raw);
1421         return (pools);
1422 }
1423
1424 static int
1425 name_or_guid_exists(zpool_handle_t *zhp, void *data)
1426 {
1427         importargs_t *import = data;
1428         int found = 0;
1429
1430         if (import->poolname != NULL) {
1431                 char *pool_name;
1432
1433                 verify(nvlist_lookup_string(zhp->zpool_config,
1434                     ZPOOL_CONFIG_POOL_NAME, &pool_name) == 0);
1435                 if (strcmp(pool_name, import->poolname) == 0)
1436                         found = 1;
1437         } else {
1438                 uint64_t pool_guid;
1439
1440                 verify(nvlist_lookup_uint64(zhp->zpool_config,
1441                     ZPOOL_CONFIG_POOL_GUID, &pool_guid) == 0);
1442                 if (pool_guid == import->guid)
1443                         found = 1;
1444         }
1445
1446         zpool_close(zhp);
1447         return (found);
1448 }
1449
1450 nvlist_t *
1451 zpool_search_import(libzfs_handle_t *hdl, importargs_t *import)
1452 {
1453         verify(import->poolname == NULL || import->guid == 0);
1454
1455         if (import->unique)
1456                 import->exists = zpool_iter(hdl, name_or_guid_exists, import);
1457
1458         if (import->cachefile != NULL)
1459                 return (zpool_find_import_cached(hdl, import->cachefile,
1460                     import->poolname, import->guid));
1461
1462         return (zpool_find_import_impl(hdl, import));
1463 }
1464
1465 boolean_t
1466 find_guid(nvlist_t *nv, uint64_t guid)
1467 {
1468         uint64_t tmp;
1469         nvlist_t **child;
1470         uint_t c, children;
1471
1472         verify(nvlist_lookup_uint64(nv, ZPOOL_CONFIG_GUID, &tmp) == 0);
1473         if (tmp == guid)
1474                 return (B_TRUE);
1475
1476         if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
1477             &child, &children) == 0) {
1478                 for (c = 0; c < children; c++)
1479                         if (find_guid(child[c], guid))
1480                                 return (B_TRUE);
1481         }
1482
1483         return (B_FALSE);
1484 }
1485
1486 typedef struct aux_cbdata {
1487         const char      *cb_type;
1488         uint64_t        cb_guid;
1489         zpool_handle_t  *cb_zhp;
1490 } aux_cbdata_t;
1491
1492 static int
1493 find_aux(zpool_handle_t *zhp, void *data)
1494 {
1495         aux_cbdata_t *cbp = data;
1496         nvlist_t **list;
1497         uint_t i, count;
1498         uint64_t guid;
1499         nvlist_t *nvroot;
1500
1501         verify(nvlist_lookup_nvlist(zhp->zpool_config, ZPOOL_CONFIG_VDEV_TREE,
1502             &nvroot) == 0);
1503
1504         if (nvlist_lookup_nvlist_array(nvroot, cbp->cb_type,
1505             &list, &count) == 0) {
1506                 for (i = 0; i < count; i++) {
1507                         verify(nvlist_lookup_uint64(list[i],
1508                             ZPOOL_CONFIG_GUID, &guid) == 0);
1509                         if (guid == cbp->cb_guid) {
1510                                 cbp->cb_zhp = zhp;
1511                                 return (1);
1512                         }
1513                 }
1514         }
1515
1516         zpool_close(zhp);
1517         return (0);
1518 }
1519
1520 /*
1521  * Determines if the pool is in use.  If so, it returns true and the state of
1522  * the pool as well as the name of the pool.  Both strings are allocated and
1523  * must be freed by the caller.
1524  */
1525 int
1526 zpool_in_use(libzfs_handle_t *hdl, int fd, pool_state_t *state, char **namestr,
1527     boolean_t *inuse)
1528 {
1529         nvlist_t *config;
1530         char *name;
1531         boolean_t ret;
1532         uint64_t guid, vdev_guid;
1533         zpool_handle_t *zhp;
1534         nvlist_t *pool_config;
1535         uint64_t stateval, isspare;
1536         aux_cbdata_t cb = { 0 };
1537         boolean_t isactive;
1538
1539         *inuse = B_FALSE;
1540
1541         if (zpool_read_label(fd, &config) != 0) {
1542                 (void) no_memory(hdl);
1543                 return (-1);
1544         }
1545
1546         if (config == NULL)
1547                 return (0);
1548
1549         verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_STATE,
1550             &stateval) == 0);
1551         verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID,
1552             &vdev_guid) == 0);
1553
1554         if (stateval != POOL_STATE_SPARE && stateval != POOL_STATE_L2CACHE) {
1555                 verify(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
1556                     &name) == 0);
1557                 verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
1558                     &guid) == 0);
1559         }
1560
1561         switch (stateval) {
1562         case POOL_STATE_EXPORTED:
1563                 /*
1564                  * A pool with an exported state may in fact be imported
1565                  * read-only, so check the in-core state to see if it's
1566                  * active and imported read-only.  If it is, set
1567                  * its state to active.
1568                  */
1569                 if (pool_active(hdl, name, guid, &isactive) == 0 && isactive &&
1570                     (zhp = zpool_open_canfail(hdl, name)) != NULL &&
1571                     zpool_get_prop_int(zhp, ZPOOL_PROP_READONLY, NULL))
1572                         stateval = POOL_STATE_ACTIVE;
1573
1574                 ret = B_TRUE;
1575                 break;
1576
1577         case POOL_STATE_ACTIVE:
1578                 /*
1579                  * For an active pool, we have to determine if it's really part
1580                  * of a currently active pool (in which case the pool will exist
1581                  * and the guid will be the same), or whether it's part of an
1582                  * active pool that was disconnected without being explicitly
1583                  * exported.
1584                  */
1585                 if (pool_active(hdl, name, guid, &isactive) != 0) {
1586                         nvlist_free(config);
1587                         return (-1);
1588                 }
1589
1590                 if (isactive) {
1591                         /*
1592                          * Because the device may have been removed while
1593                          * offlined, we only report it as active if the vdev is
1594                          * still present in the config.  Otherwise, pretend like
1595                          * it's not in use.
1596                          */
1597                         if ((zhp = zpool_open_canfail(hdl, name)) != NULL &&
1598                             (pool_config = zpool_get_config(zhp, NULL))
1599                             != NULL) {
1600                                 nvlist_t *nvroot;
1601
1602                                 verify(nvlist_lookup_nvlist(pool_config,
1603                                     ZPOOL_CONFIG_VDEV_TREE, &nvroot) == 0);
1604                                 ret = find_guid(nvroot, vdev_guid);
1605                         } else {
1606                                 ret = B_FALSE;
1607                         }
1608
1609                         /*
1610                          * If this is an active spare within another pool, we
1611                          * treat it like an unused hot spare.  This allows the
1612                          * user to create a pool with a hot spare that currently
1613                          * in use within another pool.  Since we return B_TRUE,
1614                          * libdiskmgt will continue to prevent generic consumers
1615                          * from using the device.
1616                          */
1617                         if (ret && nvlist_lookup_uint64(config,
1618                             ZPOOL_CONFIG_IS_SPARE, &isspare) == 0 && isspare)
1619                                 stateval = POOL_STATE_SPARE;
1620
1621                         if (zhp != NULL)
1622                                 zpool_close(zhp);
1623                 } else {
1624                         stateval = POOL_STATE_POTENTIALLY_ACTIVE;
1625                         ret = B_TRUE;
1626                 }
1627                 break;
1628
1629         case POOL_STATE_SPARE:
1630                 /*
1631                  * For a hot spare, it can be either definitively in use, or
1632                  * potentially active.  To determine if it's in use, we iterate
1633                  * over all pools in the system and search for one with a spare
1634                  * with a matching guid.
1635                  *
1636                  * Due to the shared nature of spares, we don't actually report
1637                  * the potentially active case as in use.  This means the user
1638                  * can freely create pools on the hot spares of exported pools,
1639                  * but to do otherwise makes the resulting code complicated, and
1640                  * we end up having to deal with this case anyway.
1641                  */
1642                 cb.cb_zhp = NULL;
1643                 cb.cb_guid = vdev_guid;
1644                 cb.cb_type = ZPOOL_CONFIG_SPARES;
1645                 if (zpool_iter(hdl, find_aux, &cb) == 1) {
1646                         name = (char *)zpool_get_name(cb.cb_zhp);
1647                         ret = TRUE;
1648                 } else {
1649                         ret = FALSE;
1650                 }
1651                 break;
1652
1653         case POOL_STATE_L2CACHE:
1654
1655                 /*
1656                  * Check if any pool is currently using this l2cache device.
1657                  */
1658                 cb.cb_zhp = NULL;
1659                 cb.cb_guid = vdev_guid;
1660                 cb.cb_type = ZPOOL_CONFIG_L2CACHE;
1661                 if (zpool_iter(hdl, find_aux, &cb) == 1) {
1662                         name = (char *)zpool_get_name(cb.cb_zhp);
1663                         ret = TRUE;
1664                 } else {
1665                         ret = FALSE;
1666                 }
1667                 break;
1668
1669         default:
1670                 ret = B_FALSE;
1671         }
1672
1673
1674         if (ret) {
1675                 if ((*namestr = zfs_strdup(hdl, name)) == NULL) {
1676                         if (cb.cb_zhp)
1677                                 zpool_close(cb.cb_zhp);
1678                         nvlist_free(config);
1679                         return (-1);
1680                 }
1681                 *state = (pool_state_t)stateval;
1682         }
1683
1684         if (cb.cb_zhp)
1685                 zpool_close(cb.cb_zhp);
1686
1687         nvlist_free(config);
1688         *inuse = ret;
1689         return (0);
1690 }