xref: /titanic_50/usr/src/lib/libzfs/common/libzfs_import.c (revision aab83bb83be7342f6cfccaed8d5fe0b2f404855d)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2015 Nexenta Systems, Inc.  All rights reserved.
24  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
25  * Copyright (c) 2013 by Delphix. All rights reserved.
26  * Copyright 2015 RackTop Systems.
27  */
28 
29 /*
30  * Pool import support functions.
31  *
32  * To import a pool, we rely on reading the configuration information from the
33  * ZFS label of each device.  If we successfully read the label, then we
34  * organize the configuration information in the following hierarchy:
35  *
36  * 	pool guid -> toplevel vdev guid -> label txg
37  *
38  * Duplicate entries matching this same tuple will be discarded.  Once we have
39  * examined every device, we pick the best label txg config for each toplevel
40  * vdev.  We then arrange these toplevel vdevs into a complete pool config, and
41  * update any paths that have changed.  Finally, we attempt to import the pool
42  * using our derived config, and record the results.
43  */
44 
45 #include <ctype.h>
46 #include <devid.h>
47 #include <dirent.h>
48 #include <errno.h>
49 #include <libintl.h>
50 #include <stddef.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <sys/stat.h>
54 #include <unistd.h>
55 #include <fcntl.h>
56 #include <sys/vtoc.h>
57 #include <sys/dktp/fdisk.h>
58 #include <sys/efi_partition.h>
59 #include <thread_pool.h>
60 
61 #include <sys/vdev_impl.h>
62 
63 #include "libzfs.h"
64 #include "libzfs_impl.h"
65 
66 /*
67  * Intermediate structures used to gather configuration information.
68  */
69 typedef struct config_entry {
70 	uint64_t		ce_txg;
71 	nvlist_t		*ce_config;
72 	struct config_entry	*ce_next;
73 } config_entry_t;
74 
75 typedef struct vdev_entry {
76 	uint64_t		ve_guid;
77 	config_entry_t		*ve_configs;
78 	struct vdev_entry	*ve_next;
79 } vdev_entry_t;
80 
81 typedef struct pool_entry {
82 	uint64_t		pe_guid;
83 	vdev_entry_t		*pe_vdevs;
84 	struct pool_entry	*pe_next;
85 } pool_entry_t;
86 
87 typedef struct name_entry {
88 	char			*ne_name;
89 	uint64_t		ne_guid;
90 	struct name_entry	*ne_next;
91 } name_entry_t;
92 
93 typedef struct pool_list {
94 	pool_entry_t		*pools;
95 	name_entry_t		*names;
96 } pool_list_t;
97 
98 static char *
get_devid(const char * path)99 get_devid(const char *path)
100 {
101 	int fd;
102 	ddi_devid_t devid;
103 	char *minor, *ret;
104 
105 	if ((fd = open(path, O_RDONLY)) < 0)
106 		return (NULL);
107 
108 	minor = NULL;
109 	ret = NULL;
110 	if (devid_get(fd, &devid) == 0) {
111 		if (devid_get_minor_name(fd, &minor) == 0)
112 			ret = devid_str_encode(devid, minor);
113 		if (minor != NULL)
114 			devid_str_free(minor);
115 		devid_free(devid);
116 	}
117 	(void) close(fd);
118 
119 	return (ret);
120 }
121 
122 
123 /*
124  * Go through and fix up any path and/or devid information for the given vdev
125  * configuration.
126  */
127 static int
fix_paths(nvlist_t * nv,name_entry_t * names)128 fix_paths(nvlist_t *nv, name_entry_t *names)
129 {
130 	nvlist_t **child;
131 	uint_t c, children;
132 	uint64_t guid;
133 	name_entry_t *ne, *best;
134 	char *path, *devid;
135 	int matched;
136 
137 	if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
138 	    &child, &children) == 0) {
139 		for (c = 0; c < children; c++)
140 			if (fix_paths(child[c], names) != 0)
141 				return (-1);
142 		return (0);
143 	}
144 
145 	/*
146 	 * This is a leaf (file or disk) vdev.  In either case, go through
147 	 * the name list and see if we find a matching guid.  If so, replace
148 	 * the path and see if we can calculate a new devid.
149 	 *
150 	 * There may be multiple names associated with a particular guid, in
151 	 * which case we have overlapping slices or multiple paths to the same
152 	 * disk.  If this is the case, then we want to pick the path that is
153 	 * the most similar to the original, where "most similar" is the number
154 	 * of matching characters starting from the end of the path.  This will
155 	 * preserve slice numbers even if the disks have been reorganized, and
156 	 * will also catch preferred disk names if multiple paths exist.
157 	 */
158 	verify(nvlist_lookup_uint64(nv, ZPOOL_CONFIG_GUID, &guid) == 0);
159 	if (nvlist_lookup_string(nv, ZPOOL_CONFIG_PATH, &path) != 0)
160 		path = NULL;
161 
162 	matched = 0;
163 	best = NULL;
164 	for (ne = names; ne != NULL; ne = ne->ne_next) {
165 		if (ne->ne_guid == guid) {
166 			const char *src, *dst;
167 			int count;
168 
169 			if (path == NULL) {
170 				best = ne;
171 				break;
172 			}
173 
174 			src = ne->ne_name + strlen(ne->ne_name) - 1;
175 			dst = path + strlen(path) - 1;
176 			for (count = 0; src >= ne->ne_name && dst >= path;
177 			    src--, dst--, count++)
178 				if (*src != *dst)
179 					break;
180 
181 			/*
182 			 * At this point, 'count' is the number of characters
183 			 * matched from the end.
184 			 */
185 			if (count > matched || best == NULL) {
186 				best = ne;
187 				matched = count;
188 			}
189 		}
190 	}
191 
192 	if (best == NULL)
193 		return (0);
194 
195 	if (nvlist_add_string(nv, ZPOOL_CONFIG_PATH, best->ne_name) != 0)
196 		return (-1);
197 
198 	if ((devid = get_devid(best->ne_name)) == NULL) {
199 		(void) nvlist_remove_all(nv, ZPOOL_CONFIG_DEVID);
200 	} else {
201 		if (nvlist_add_string(nv, ZPOOL_CONFIG_DEVID, devid) != 0) {
202 			devid_str_free(devid);
203 			return (-1);
204 		}
205 		devid_str_free(devid);
206 	}
207 
208 	return (0);
209 }
210 
211 /*
212  * Add the given configuration to the list of known devices.
213  */
214 static int
add_config(libzfs_handle_t * hdl,pool_list_t * pl,const char * path,nvlist_t * config)215 add_config(libzfs_handle_t *hdl, pool_list_t *pl, const char *path,
216     nvlist_t *config)
217 {
218 	uint64_t pool_guid, vdev_guid, top_guid, txg, state;
219 	pool_entry_t *pe;
220 	vdev_entry_t *ve;
221 	config_entry_t *ce;
222 	name_entry_t *ne;
223 
224 	/*
225 	 * If this is a hot spare not currently in use or level 2 cache
226 	 * device, add it to the list of names to translate, but don't do
227 	 * anything else.
228 	 */
229 	if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_STATE,
230 	    &state) == 0 &&
231 	    (state == POOL_STATE_SPARE || state == POOL_STATE_L2CACHE) &&
232 	    nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID, &vdev_guid) == 0) {
233 		if ((ne = zfs_alloc(hdl, sizeof (name_entry_t))) == NULL)
234 			return (-1);
235 
236 		if ((ne->ne_name = zfs_strdup(hdl, path)) == NULL) {
237 			free(ne);
238 			return (-1);
239 		}
240 		ne->ne_guid = vdev_guid;
241 		ne->ne_next = pl->names;
242 		pl->names = ne;
243 		return (0);
244 	}
245 
246 	/*
247 	 * If we have a valid config but cannot read any of these fields, then
248 	 * it means we have a half-initialized label.  In vdev_label_init()
249 	 * we write a label with txg == 0 so that we can identify the device
250 	 * in case the user refers to the same disk later on.  If we fail to
251 	 * create the pool, we'll be left with a label in this state
252 	 * which should not be considered part of a valid pool.
253 	 */
254 	if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
255 	    &pool_guid) != 0 ||
256 	    nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID,
257 	    &vdev_guid) != 0 ||
258 	    nvlist_lookup_uint64(config, ZPOOL_CONFIG_TOP_GUID,
259 	    &top_guid) != 0 ||
260 	    nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_TXG,
261 	    &txg) != 0 || txg == 0) {
262 		nvlist_free(config);
263 		return (0);
264 	}
265 
266 	/*
267 	 * First, see if we know about this pool.  If not, then add it to the
268 	 * list of known pools.
269 	 */
270 	for (pe = pl->pools; pe != NULL; pe = pe->pe_next) {
271 		if (pe->pe_guid == pool_guid)
272 			break;
273 	}
274 
275 	if (pe == NULL) {
276 		if ((pe = zfs_alloc(hdl, sizeof (pool_entry_t))) == NULL) {
277 			nvlist_free(config);
278 			return (-1);
279 		}
280 		pe->pe_guid = pool_guid;
281 		pe->pe_next = pl->pools;
282 		pl->pools = pe;
283 	}
284 
285 	/*
286 	 * Second, see if we know about this toplevel vdev.  Add it if its
287 	 * missing.
288 	 */
289 	for (ve = pe->pe_vdevs; ve != NULL; ve = ve->ve_next) {
290 		if (ve->ve_guid == top_guid)
291 			break;
292 	}
293 
294 	if (ve == NULL) {
295 		if ((ve = zfs_alloc(hdl, sizeof (vdev_entry_t))) == NULL) {
296 			nvlist_free(config);
297 			return (-1);
298 		}
299 		ve->ve_guid = top_guid;
300 		ve->ve_next = pe->pe_vdevs;
301 		pe->pe_vdevs = ve;
302 	}
303 
304 	/*
305 	 * Third, see if we have a config with a matching transaction group.  If
306 	 * so, then we do nothing.  Otherwise, add it to the list of known
307 	 * configs.
308 	 */
309 	for (ce = ve->ve_configs; ce != NULL; ce = ce->ce_next) {
310 		if (ce->ce_txg == txg)
311 			break;
312 	}
313 
314 	if (ce == NULL) {
315 		if ((ce = zfs_alloc(hdl, sizeof (config_entry_t))) == NULL) {
316 			nvlist_free(config);
317 			return (-1);
318 		}
319 		ce->ce_txg = txg;
320 		ce->ce_config = config;
321 		ce->ce_next = ve->ve_configs;
322 		ve->ve_configs = ce;
323 	} else {
324 		nvlist_free(config);
325 	}
326 
327 	/*
328 	 * At this point we've successfully added our config to the list of
329 	 * known configs.  The last thing to do is add the vdev guid -> path
330 	 * mappings so that we can fix up the configuration as necessary before
331 	 * doing the import.
332 	 */
333 	if ((ne = zfs_alloc(hdl, sizeof (name_entry_t))) == NULL)
334 		return (-1);
335 
336 	if ((ne->ne_name = zfs_strdup(hdl, path)) == NULL) {
337 		free(ne);
338 		return (-1);
339 	}
340 
341 	ne->ne_guid = vdev_guid;
342 	ne->ne_next = pl->names;
343 	pl->names = ne;
344 
345 	return (0);
346 }
347 
348 /*
349  * Returns true if the named pool matches the given GUID.
350  */
351 static int
pool_active(libzfs_handle_t * hdl,const char * name,uint64_t guid,boolean_t * isactive)352 pool_active(libzfs_handle_t *hdl, const char *name, uint64_t guid,
353     boolean_t *isactive)
354 {
355 	zpool_handle_t *zhp;
356 	uint64_t theguid;
357 
358 	if (zpool_open_silent(hdl, name, &zhp) != 0)
359 		return (-1);
360 
361 	if (zhp == NULL) {
362 		*isactive = B_FALSE;
363 		return (0);
364 	}
365 
366 	verify(nvlist_lookup_uint64(zhp->zpool_config, ZPOOL_CONFIG_POOL_GUID,
367 	    &theguid) == 0);
368 
369 	zpool_close(zhp);
370 
371 	*isactive = (theguid == guid);
372 	return (0);
373 }
374 
375 static nvlist_t *
refresh_config(libzfs_handle_t * hdl,nvlist_t * config)376 refresh_config(libzfs_handle_t *hdl, nvlist_t *config)
377 {
378 	nvlist_t *nvl;
379 	zfs_cmd_t zc = { 0 };
380 	int err;
381 
382 	if (zcmd_write_conf_nvlist(hdl, &zc, config) != 0)
383 		return (NULL);
384 
385 	if (zcmd_alloc_dst_nvlist(hdl, &zc,
386 	    zc.zc_nvlist_conf_size * 2) != 0) {
387 		zcmd_free_nvlists(&zc);
388 		return (NULL);
389 	}
390 
391 	while ((err = ioctl(hdl->libzfs_fd, ZFS_IOC_POOL_TRYIMPORT,
392 	    &zc)) != 0 && errno == ENOMEM) {
393 		if (zcmd_expand_dst_nvlist(hdl, &zc) != 0) {
394 			zcmd_free_nvlists(&zc);
395 			return (NULL);
396 		}
397 	}
398 
399 	if (err) {
400 		zcmd_free_nvlists(&zc);
401 		return (NULL);
402 	}
403 
404 	if (zcmd_read_dst_nvlist(hdl, &zc, &nvl) != 0) {
405 		zcmd_free_nvlists(&zc);
406 		return (NULL);
407 	}
408 
409 	zcmd_free_nvlists(&zc);
410 	return (nvl);
411 }
412 
413 /*
414  * Determine if the vdev id is a hole in the namespace.
415  */
416 boolean_t
vdev_is_hole(uint64_t * hole_array,uint_t holes,uint_t id)417 vdev_is_hole(uint64_t *hole_array, uint_t holes, uint_t id)
418 {
419 	for (int c = 0; c < holes; c++) {
420 
421 		/* Top-level is a hole */
422 		if (hole_array[c] == id)
423 			return (B_TRUE);
424 	}
425 	return (B_FALSE);
426 }
427 
428 /*
429  * Convert our list of pools into the definitive set of configurations.  We
430  * start by picking the best config for each toplevel vdev.  Once that's done,
431  * we assemble the toplevel vdevs into a full config for the pool.  We make a
432  * pass to fix up any incorrect paths, and then add it to the main list to
433  * return to the user.
434  */
435 static nvlist_t *
get_configs(libzfs_handle_t * hdl,pool_list_t * pl,boolean_t active_ok)436 get_configs(libzfs_handle_t *hdl, pool_list_t *pl, boolean_t active_ok)
437 {
438 	pool_entry_t *pe;
439 	vdev_entry_t *ve;
440 	config_entry_t *ce;
441 	nvlist_t *ret = NULL, *config = NULL, *tmp, *nvtop, *nvroot;
442 	nvlist_t **spares, **l2cache;
443 	uint_t i, nspares, nl2cache;
444 	boolean_t config_seen;
445 	uint64_t best_txg;
446 	char *name, *hostname;
447 	uint64_t guid;
448 	uint_t children = 0;
449 	nvlist_t **child = NULL;
450 	uint_t holes;
451 	uint64_t *hole_array, max_id;
452 	uint_t c;
453 	boolean_t isactive;
454 	uint64_t hostid;
455 	nvlist_t *nvl;
456 	boolean_t found_one = B_FALSE;
457 	boolean_t valid_top_config = B_FALSE;
458 
459 	if (nvlist_alloc(&ret, 0, 0) != 0)
460 		goto nomem;
461 
462 	for (pe = pl->pools; pe != NULL; pe = pe->pe_next) {
463 		uint64_t id, max_txg = 0;
464 
465 		if (nvlist_alloc(&config, NV_UNIQUE_NAME, 0) != 0)
466 			goto nomem;
467 		config_seen = B_FALSE;
468 
469 		/*
470 		 * Iterate over all toplevel vdevs.  Grab the pool configuration
471 		 * from the first one we find, and then go through the rest and
472 		 * add them as necessary to the 'vdevs' member of the config.
473 		 */
474 		for (ve = pe->pe_vdevs; ve != NULL; ve = ve->ve_next) {
475 
476 			/*
477 			 * Determine the best configuration for this vdev by
478 			 * selecting the config with the latest transaction
479 			 * group.
480 			 */
481 			best_txg = 0;
482 			for (ce = ve->ve_configs; ce != NULL;
483 			    ce = ce->ce_next) {
484 
485 				if (ce->ce_txg > best_txg) {
486 					tmp = ce->ce_config;
487 					best_txg = ce->ce_txg;
488 				}
489 			}
490 
491 			/*
492 			 * We rely on the fact that the max txg for the
493 			 * pool will contain the most up-to-date information
494 			 * about the valid top-levels in the vdev namespace.
495 			 */
496 			if (best_txg > max_txg) {
497 				(void) nvlist_remove(config,
498 				    ZPOOL_CONFIG_VDEV_CHILDREN,
499 				    DATA_TYPE_UINT64);
500 				(void) nvlist_remove(config,
501 				    ZPOOL_CONFIG_HOLE_ARRAY,
502 				    DATA_TYPE_UINT64_ARRAY);
503 
504 				max_txg = best_txg;
505 				hole_array = NULL;
506 				holes = 0;
507 				max_id = 0;
508 				valid_top_config = B_FALSE;
509 
510 				if (nvlist_lookup_uint64(tmp,
511 				    ZPOOL_CONFIG_VDEV_CHILDREN, &max_id) == 0) {
512 					verify(nvlist_add_uint64(config,
513 					    ZPOOL_CONFIG_VDEV_CHILDREN,
514 					    max_id) == 0);
515 					valid_top_config = B_TRUE;
516 				}
517 
518 				if (nvlist_lookup_uint64_array(tmp,
519 				    ZPOOL_CONFIG_HOLE_ARRAY, &hole_array,
520 				    &holes) == 0) {
521 					verify(nvlist_add_uint64_array(config,
522 					    ZPOOL_CONFIG_HOLE_ARRAY,
523 					    hole_array, holes) == 0);
524 				}
525 			}
526 
527 			if (!config_seen) {
528 				/*
529 				 * Copy the relevant pieces of data to the pool
530 				 * configuration:
531 				 *
532 				 *	version
533 				 *	pool guid
534 				 *	name
535 				 *	comment (if available)
536 				 *	pool state
537 				 *	hostid (if available)
538 				 *	hostname (if available)
539 				 */
540 				uint64_t state, version;
541 				char *comment = NULL;
542 
543 				version = fnvlist_lookup_uint64(tmp,
544 				    ZPOOL_CONFIG_VERSION);
545 				fnvlist_add_uint64(config,
546 				    ZPOOL_CONFIG_VERSION, version);
547 				guid = fnvlist_lookup_uint64(tmp,
548 				    ZPOOL_CONFIG_POOL_GUID);
549 				fnvlist_add_uint64(config,
550 				    ZPOOL_CONFIG_POOL_GUID, guid);
551 				name = fnvlist_lookup_string(tmp,
552 				    ZPOOL_CONFIG_POOL_NAME);
553 				fnvlist_add_string(config,
554 				    ZPOOL_CONFIG_POOL_NAME, name);
555 
556 				if (nvlist_lookup_string(tmp,
557 				    ZPOOL_CONFIG_COMMENT, &comment) == 0)
558 					fnvlist_add_string(config,
559 					    ZPOOL_CONFIG_COMMENT, comment);
560 
561 				state = fnvlist_lookup_uint64(tmp,
562 				    ZPOOL_CONFIG_POOL_STATE);
563 				fnvlist_add_uint64(config,
564 				    ZPOOL_CONFIG_POOL_STATE, state);
565 
566 				hostid = 0;
567 				if (nvlist_lookup_uint64(tmp,
568 				    ZPOOL_CONFIG_HOSTID, &hostid) == 0) {
569 					fnvlist_add_uint64(config,
570 					    ZPOOL_CONFIG_HOSTID, hostid);
571 					hostname = fnvlist_lookup_string(tmp,
572 					    ZPOOL_CONFIG_HOSTNAME);
573 					fnvlist_add_string(config,
574 					    ZPOOL_CONFIG_HOSTNAME, hostname);
575 				}
576 
577 				config_seen = B_TRUE;
578 			}
579 
580 			/*
581 			 * Add this top-level vdev to the child array.
582 			 */
583 			verify(nvlist_lookup_nvlist(tmp,
584 			    ZPOOL_CONFIG_VDEV_TREE, &nvtop) == 0);
585 			verify(nvlist_lookup_uint64(nvtop, ZPOOL_CONFIG_ID,
586 			    &id) == 0);
587 
588 			if (id >= children) {
589 				nvlist_t **newchild;
590 
591 				newchild = zfs_alloc(hdl, (id + 1) *
592 				    sizeof (nvlist_t *));
593 				if (newchild == NULL)
594 					goto nomem;
595 
596 				for (c = 0; c < children; c++)
597 					newchild[c] = child[c];
598 
599 				free(child);
600 				child = newchild;
601 				children = id + 1;
602 			}
603 			if (nvlist_dup(nvtop, &child[id], 0) != 0)
604 				goto nomem;
605 
606 		}
607 
608 		/*
609 		 * If we have information about all the top-levels then
610 		 * clean up the nvlist which we've constructed. This
611 		 * means removing any extraneous devices that are
612 		 * beyond the valid range or adding devices to the end
613 		 * of our array which appear to be missing.
614 		 */
615 		if (valid_top_config) {
616 			if (max_id < children) {
617 				for (c = max_id; c < children; c++)
618 					nvlist_free(child[c]);
619 				children = max_id;
620 			} else if (max_id > children) {
621 				nvlist_t **newchild;
622 
623 				newchild = zfs_alloc(hdl, (max_id) *
624 				    sizeof (nvlist_t *));
625 				if (newchild == NULL)
626 					goto nomem;
627 
628 				for (c = 0; c < children; c++)
629 					newchild[c] = child[c];
630 
631 				free(child);
632 				child = newchild;
633 				children = max_id;
634 			}
635 		}
636 
637 		verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
638 		    &guid) == 0);
639 
640 		/*
641 		 * The vdev namespace may contain holes as a result of
642 		 * device removal. We must add them back into the vdev
643 		 * tree before we process any missing devices.
644 		 */
645 		if (holes > 0) {
646 			ASSERT(valid_top_config);
647 
648 			for (c = 0; c < children; c++) {
649 				nvlist_t *holey;
650 
651 				if (child[c] != NULL ||
652 				    !vdev_is_hole(hole_array, holes, c))
653 					continue;
654 
655 				if (nvlist_alloc(&holey, NV_UNIQUE_NAME,
656 				    0) != 0)
657 					goto nomem;
658 
659 				/*
660 				 * Holes in the namespace are treated as
661 				 * "hole" top-level vdevs and have a
662 				 * special flag set on them.
663 				 */
664 				if (nvlist_add_string(holey,
665 				    ZPOOL_CONFIG_TYPE,
666 				    VDEV_TYPE_HOLE) != 0 ||
667 				    nvlist_add_uint64(holey,
668 				    ZPOOL_CONFIG_ID, c) != 0 ||
669 				    nvlist_add_uint64(holey,
670 				    ZPOOL_CONFIG_GUID, 0ULL) != 0) {
671 					nvlist_free(holey);
672 					goto nomem;
673 				}
674 				child[c] = holey;
675 			}
676 		}
677 
678 		/*
679 		 * Look for any missing top-level vdevs.  If this is the case,
680 		 * create a faked up 'missing' vdev as a placeholder.  We cannot
681 		 * simply compress the child array, because the kernel performs
682 		 * certain checks to make sure the vdev IDs match their location
683 		 * in the configuration.
684 		 */
685 		for (c = 0; c < children; c++) {
686 			if (child[c] == NULL) {
687 				nvlist_t *missing;
688 				if (nvlist_alloc(&missing, NV_UNIQUE_NAME,
689 				    0) != 0)
690 					goto nomem;
691 				if (nvlist_add_string(missing,
692 				    ZPOOL_CONFIG_TYPE,
693 				    VDEV_TYPE_MISSING) != 0 ||
694 				    nvlist_add_uint64(missing,
695 				    ZPOOL_CONFIG_ID, c) != 0 ||
696 				    nvlist_add_uint64(missing,
697 				    ZPOOL_CONFIG_GUID, 0ULL) != 0) {
698 					nvlist_free(missing);
699 					goto nomem;
700 				}
701 				child[c] = missing;
702 			}
703 		}
704 
705 		/*
706 		 * Put all of this pool's top-level vdevs into a root vdev.
707 		 */
708 		if (nvlist_alloc(&nvroot, NV_UNIQUE_NAME, 0) != 0)
709 			goto nomem;
710 		if (nvlist_add_string(nvroot, ZPOOL_CONFIG_TYPE,
711 		    VDEV_TYPE_ROOT) != 0 ||
712 		    nvlist_add_uint64(nvroot, ZPOOL_CONFIG_ID, 0ULL) != 0 ||
713 		    nvlist_add_uint64(nvroot, ZPOOL_CONFIG_GUID, guid) != 0 ||
714 		    nvlist_add_nvlist_array(nvroot, ZPOOL_CONFIG_CHILDREN,
715 		    child, children) != 0) {
716 			nvlist_free(nvroot);
717 			goto nomem;
718 		}
719 
720 		for (c = 0; c < children; c++)
721 			nvlist_free(child[c]);
722 		free(child);
723 		children = 0;
724 		child = NULL;
725 
726 		/*
727 		 * Go through and fix up any paths and/or devids based on our
728 		 * known list of vdev GUID -> path mappings.
729 		 */
730 		if (fix_paths(nvroot, pl->names) != 0) {
731 			nvlist_free(nvroot);
732 			goto nomem;
733 		}
734 
735 		/*
736 		 * Add the root vdev to this pool's configuration.
737 		 */
738 		if (nvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
739 		    nvroot) != 0) {
740 			nvlist_free(nvroot);
741 			goto nomem;
742 		}
743 		nvlist_free(nvroot);
744 
745 		/*
746 		 * zdb uses this path to report on active pools that were
747 		 * imported or created using -R.
748 		 */
749 		if (active_ok)
750 			goto add_pool;
751 
752 		/*
753 		 * Determine if this pool is currently active, in which case we
754 		 * can't actually import it.
755 		 */
756 		verify(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
757 		    &name) == 0);
758 		verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
759 		    &guid) == 0);
760 
761 		if (pool_active(hdl, name, guid, &isactive) != 0)
762 			goto error;
763 
764 		if (isactive) {
765 			nvlist_free(config);
766 			config = NULL;
767 			continue;
768 		}
769 
770 		if ((nvl = refresh_config(hdl, config)) == NULL) {
771 			nvlist_free(config);
772 			config = NULL;
773 			continue;
774 		}
775 
776 		nvlist_free(config);
777 		config = nvl;
778 
779 		/*
780 		 * Go through and update the paths for spares, now that we have
781 		 * them.
782 		 */
783 		verify(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
784 		    &nvroot) == 0);
785 		if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES,
786 		    &spares, &nspares) == 0) {
787 			for (i = 0; i < nspares; i++) {
788 				if (fix_paths(spares[i], pl->names) != 0)
789 					goto nomem;
790 			}
791 		}
792 
793 		/*
794 		 * Update the paths for l2cache devices.
795 		 */
796 		if (nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_L2CACHE,
797 		    &l2cache, &nl2cache) == 0) {
798 			for (i = 0; i < nl2cache; i++) {
799 				if (fix_paths(l2cache[i], pl->names) != 0)
800 					goto nomem;
801 			}
802 		}
803 
804 		/*
805 		 * Restore the original information read from the actual label.
806 		 */
807 		(void) nvlist_remove(config, ZPOOL_CONFIG_HOSTID,
808 		    DATA_TYPE_UINT64);
809 		(void) nvlist_remove(config, ZPOOL_CONFIG_HOSTNAME,
810 		    DATA_TYPE_STRING);
811 		if (hostid != 0) {
812 			verify(nvlist_add_uint64(config, ZPOOL_CONFIG_HOSTID,
813 			    hostid) == 0);
814 			verify(nvlist_add_string(config, ZPOOL_CONFIG_HOSTNAME,
815 			    hostname) == 0);
816 		}
817 
818 add_pool:
819 		/*
820 		 * Add this pool to the list of configs.
821 		 */
822 		verify(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
823 		    &name) == 0);
824 		if (nvlist_add_nvlist(ret, name, config) != 0)
825 			goto nomem;
826 
827 		found_one = B_TRUE;
828 		nvlist_free(config);
829 		config = NULL;
830 	}
831 
832 	if (!found_one) {
833 		nvlist_free(ret);
834 		ret = NULL;
835 	}
836 
837 	return (ret);
838 
839 nomem:
840 	(void) no_memory(hdl);
841 error:
842 	nvlist_free(config);
843 	nvlist_free(ret);
844 	for (c = 0; c < children; c++)
845 		nvlist_free(child[c]);
846 	free(child);
847 
848 	return (NULL);
849 }
850 
851 /*
852  * Return the offset of the given label.
853  */
854 static uint64_t
label_offset(uint64_t size,int l)855 label_offset(uint64_t size, int l)
856 {
857 	ASSERT(P2PHASE_TYPED(size, sizeof (vdev_label_t), uint64_t) == 0);
858 	return (l * sizeof (vdev_label_t) + (l < VDEV_LABELS / 2 ?
859 	    0 : size - VDEV_LABELS * sizeof (vdev_label_t)));
860 }
861 
862 /*
863  * Given a file descriptor, read the label information and return an nvlist
864  * describing the configuration, if there is one.
865  */
866 int
zpool_read_label(int fd,nvlist_t ** config)867 zpool_read_label(int fd, nvlist_t **config)
868 {
869 	struct stat64 statbuf;
870 	int l;
871 	vdev_label_t *label;
872 	uint64_t state, txg, size;
873 
874 	*config = NULL;
875 
876 	if (fstat64(fd, &statbuf) == -1)
877 		return (0);
878 	size = P2ALIGN_TYPED(statbuf.st_size, sizeof (vdev_label_t), uint64_t);
879 
880 	if ((label = malloc(sizeof (vdev_label_t))) == NULL)
881 		return (-1);
882 
883 	for (l = 0; l < VDEV_LABELS; l++) {
884 		if (pread64(fd, label, sizeof (vdev_label_t),
885 		    label_offset(size, l)) != sizeof (vdev_label_t))
886 			continue;
887 
888 		if (nvlist_unpack(label->vl_vdev_phys.vp_nvlist,
889 		    sizeof (label->vl_vdev_phys.vp_nvlist), config, 0) != 0)
890 			continue;
891 
892 		if (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_STATE,
893 		    &state) != 0 || state > POOL_STATE_L2CACHE) {
894 			nvlist_free(*config);
895 			continue;
896 		}
897 
898 		if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE &&
899 		    (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_TXG,
900 		    &txg) != 0 || txg == 0)) {
901 			nvlist_free(*config);
902 			continue;
903 		}
904 
905 		free(label);
906 		return (0);
907 	}
908 
909 	free(label);
910 	*config = NULL;
911 	return (0);
912 }
913 
914 typedef struct rdsk_node {
915 	char *rn_name;
916 	int rn_dfd;
917 	libzfs_handle_t *rn_hdl;
918 	nvlist_t *rn_config;
919 	avl_tree_t *rn_avl;
920 	avl_node_t rn_node;
921 	boolean_t rn_nozpool;
922 } rdsk_node_t;
923 
924 static int
slice_cache_compare(const void * arg1,const void * arg2)925 slice_cache_compare(const void *arg1, const void *arg2)
926 {
927 	const char  *nm1 = ((rdsk_node_t *)arg1)->rn_name;
928 	const char  *nm2 = ((rdsk_node_t *)arg2)->rn_name;
929 	char *nm1slice, *nm2slice;
930 	int rv;
931 
932 	/*
933 	 * slices zero and two are the most likely to provide results,
934 	 * so put those first
935 	 */
936 	nm1slice = strstr(nm1, "s0");
937 	nm2slice = strstr(nm2, "s0");
938 	if (nm1slice && !nm2slice) {
939 		return (-1);
940 	}
941 	if (!nm1slice && nm2slice) {
942 		return (1);
943 	}
944 	nm1slice = strstr(nm1, "s2");
945 	nm2slice = strstr(nm2, "s2");
946 	if (nm1slice && !nm2slice) {
947 		return (-1);
948 	}
949 	if (!nm1slice && nm2slice) {
950 		return (1);
951 	}
952 
953 	rv = strcmp(nm1, nm2);
954 	if (rv == 0)
955 		return (0);
956 	return (rv > 0 ? 1 : -1);
957 }
958 
959 static void
check_one_slice(avl_tree_t * r,char * diskname,uint_t partno,diskaddr_t size,uint_t blksz)960 check_one_slice(avl_tree_t *r, char *diskname, uint_t partno,
961     diskaddr_t size, uint_t blksz)
962 {
963 	rdsk_node_t tmpnode;
964 	rdsk_node_t *node;
965 	char sname[MAXNAMELEN];
966 
967 	tmpnode.rn_name = &sname[0];
968 	(void) snprintf(tmpnode.rn_name, MAXNAMELEN, "%s%u",
969 	    diskname, partno);
970 	/*
971 	 * protect against division by zero for disk labels that
972 	 * contain a bogus sector size
973 	 */
974 	if (blksz == 0)
975 		blksz = DEV_BSIZE;
976 	/* too small to contain a zpool? */
977 	if ((size < (SPA_MINDEVSIZE / blksz)) &&
978 	    (node = avl_find(r, &tmpnode, NULL)))
979 		node->rn_nozpool = B_TRUE;
980 }
981 
982 static void
nozpool_all_slices(avl_tree_t * r,const char * sname)983 nozpool_all_slices(avl_tree_t *r, const char *sname)
984 {
985 	char diskname[MAXNAMELEN];
986 	char *ptr;
987 	int i;
988 
989 	(void) strncpy(diskname, sname, MAXNAMELEN);
990 	if (((ptr = strrchr(diskname, 's')) == NULL) &&
991 	    ((ptr = strrchr(diskname, 'p')) == NULL))
992 		return;
993 	ptr[0] = 's';
994 	ptr[1] = '\0';
995 	for (i = 0; i < NDKMAP; i++)
996 		check_one_slice(r, diskname, i, 0, 1);
997 	ptr[0] = 'p';
998 	for (i = 0; i <= FD_NUMPART; i++)
999 		check_one_slice(r, diskname, i, 0, 1);
1000 }
1001 
1002 static void
check_slices(avl_tree_t * r,int fd,const char * sname)1003 check_slices(avl_tree_t *r, int fd, const char *sname)
1004 {
1005 	struct extvtoc vtoc;
1006 	struct dk_gpt *gpt;
1007 	char diskname[MAXNAMELEN];
1008 	char *ptr;
1009 	int i;
1010 
1011 	(void) strncpy(diskname, sname, MAXNAMELEN);
1012 	if ((ptr = strrchr(diskname, 's')) == NULL || !isdigit(ptr[1]))
1013 		return;
1014 	ptr[1] = '\0';
1015 
1016 	if (read_extvtoc(fd, &vtoc) >= 0) {
1017 		for (i = 0; i < NDKMAP; i++)
1018 			check_one_slice(r, diskname, i,
1019 			    vtoc.v_part[i].p_size, vtoc.v_sectorsz);
1020 	} else if (efi_alloc_and_read(fd, &gpt) >= 0) {
1021 		/*
1022 		 * on x86 we'll still have leftover links that point
1023 		 * to slices s[9-15], so use NDKMAP instead
1024 		 */
1025 		for (i = 0; i < NDKMAP; i++)
1026 			check_one_slice(r, diskname, i,
1027 			    gpt->efi_parts[i].p_size, gpt->efi_lbasize);
1028 		/* nodes p[1-4] are never used with EFI labels */
1029 		ptr[0] = 'p';
1030 		for (i = 1; i <= FD_NUMPART; i++)
1031 			check_one_slice(r, diskname, i, 0, 1);
1032 		efi_free(gpt);
1033 	}
1034 }
1035 
1036 static void
zpool_open_func(void * arg)1037 zpool_open_func(void *arg)
1038 {
1039 	rdsk_node_t *rn = arg;
1040 	struct stat64 statbuf;
1041 	nvlist_t *config;
1042 	int fd;
1043 
1044 	if (rn->rn_nozpool)
1045 		return;
1046 	if ((fd = openat64(rn->rn_dfd, rn->rn_name, O_RDONLY)) < 0) {
1047 		/* symlink to a device that's no longer there */
1048 		if (errno == ENOENT)
1049 			nozpool_all_slices(rn->rn_avl, rn->rn_name);
1050 		return;
1051 	}
1052 	/*
1053 	 * Ignore failed stats.  We only want regular
1054 	 * files, character devs and block devs.
1055 	 */
1056 	if (fstat64(fd, &statbuf) != 0 ||
1057 	    (!S_ISREG(statbuf.st_mode) &&
1058 	    !S_ISCHR(statbuf.st_mode) &&
1059 	    !S_ISBLK(statbuf.st_mode))) {
1060 		(void) close(fd);
1061 		return;
1062 	}
1063 	/* this file is too small to hold a zpool */
1064 	if (S_ISREG(statbuf.st_mode) &&
1065 	    statbuf.st_size < SPA_MINDEVSIZE) {
1066 		(void) close(fd);
1067 		return;
1068 	} else if (!S_ISREG(statbuf.st_mode)) {
1069 		/*
1070 		 * Try to read the disk label first so we don't have to
1071 		 * open a bunch of minor nodes that can't have a zpool.
1072 		 */
1073 		check_slices(rn->rn_avl, fd, rn->rn_name);
1074 	}
1075 
1076 	if ((zpool_read_label(fd, &config)) != 0) {
1077 		(void) close(fd);
1078 		(void) no_memory(rn->rn_hdl);
1079 		return;
1080 	}
1081 	(void) close(fd);
1082 
1083 	rn->rn_config = config;
1084 }
1085 
1086 /*
1087  * Given a file descriptor, clear (zero) the label information.  This function
1088  * is currently only used in the appliance stack as part of the ZFS sysevent
1089  * module.
1090  */
1091 int
zpool_clear_label(int fd)1092 zpool_clear_label(int fd)
1093 {
1094 	struct stat64 statbuf;
1095 	int l;
1096 	vdev_label_t *label;
1097 	uint64_t size;
1098 
1099 	if (fstat64(fd, &statbuf) == -1)
1100 		return (0);
1101 	size = P2ALIGN_TYPED(statbuf.st_size, sizeof (vdev_label_t), uint64_t);
1102 
1103 	if ((label = calloc(sizeof (vdev_label_t), 1)) == NULL)
1104 		return (-1);
1105 
1106 	for (l = 0; l < VDEV_LABELS; l++) {
1107 		if (pwrite64(fd, label, sizeof (vdev_label_t),
1108 		    label_offset(size, l)) != sizeof (vdev_label_t)) {
1109 			free(label);
1110 			return (-1);
1111 		}
1112 	}
1113 
1114 	free(label);
1115 	return (0);
1116 }
1117 
1118 /*
1119  * Given a list of directories to search, find all pools stored on disk.  This
1120  * includes partial pools which are not available to import.  If no args are
1121  * given (argc is 0), then the default directory (/dev/dsk) is searched.
1122  * poolname or guid (but not both) are provided by the caller when trying
1123  * to import a specific pool.
1124  */
1125 static nvlist_t *
zpool_find_import_impl(libzfs_handle_t * hdl,importargs_t * iarg)1126 zpool_find_import_impl(libzfs_handle_t *hdl, importargs_t *iarg)
1127 {
1128 	int i, dirs = iarg->paths;
1129 	struct dirent64 *dp;
1130 	char path[MAXPATHLEN];
1131 	char *end, **dir = iarg->path;
1132 	size_t pathleft;
1133 	nvlist_t *ret = NULL;
1134 	static char *default_dir = "/dev/dsk";
1135 	pool_list_t pools = { 0 };
1136 	pool_entry_t *pe, *penext;
1137 	vdev_entry_t *ve, *venext;
1138 	config_entry_t *ce, *cenext;
1139 	name_entry_t *ne, *nenext;
1140 	avl_tree_t slice_cache;
1141 	rdsk_node_t *slice;
1142 	void *cookie;
1143 
1144 	if (dirs == 0) {
1145 		dirs = 1;
1146 		dir = &default_dir;
1147 	}
1148 
1149 	/*
1150 	 * Go through and read the label configuration information from every
1151 	 * possible device, organizing the information according to pool GUID
1152 	 * and toplevel GUID.
1153 	 */
1154 	for (i = 0; i < dirs; i++) {
1155 		tpool_t *t;
1156 		char *rdsk;
1157 		int dfd;
1158 		boolean_t config_failed = B_FALSE;
1159 		DIR *dirp;
1160 
1161 		/* use realpath to normalize the path */
1162 		if (realpath(dir[i], path) == 0) {
1163 			(void) zfs_error_fmt(hdl, EZFS_BADPATH,
1164 			    dgettext(TEXT_DOMAIN, "cannot open '%s'"), dir[i]);
1165 			goto error;
1166 		}
1167 		end = &path[strlen(path)];
1168 		*end++ = '/';
1169 		*end = 0;
1170 		pathleft = &path[sizeof (path)] - end;
1171 
1172 		/*
1173 		 * Using raw devices instead of block devices when we're
1174 		 * reading the labels skips a bunch of slow operations during
1175 		 * close(2) processing, so we replace /dev/dsk with /dev/rdsk.
1176 		 */
1177 		if (strcmp(path, "/dev/dsk/") == 0)
1178 			rdsk = "/dev/rdsk/";
1179 		else
1180 			rdsk = path;
1181 
1182 		if ((dfd = open64(rdsk, O_RDONLY)) < 0 ||
1183 		    (dirp = fdopendir(dfd)) == NULL) {
1184 			if (dfd >= 0)
1185 				(void) close(dfd);
1186 			zfs_error_aux(hdl, strerror(errno));
1187 			(void) zfs_error_fmt(hdl, EZFS_BADPATH,
1188 			    dgettext(TEXT_DOMAIN, "cannot open '%s'"),
1189 			    rdsk);
1190 			goto error;
1191 		}
1192 
1193 		avl_create(&slice_cache, slice_cache_compare,
1194 		    sizeof (rdsk_node_t), offsetof(rdsk_node_t, rn_node));
1195 		/*
1196 		 * This is not MT-safe, but we have no MT consumers of libzfs
1197 		 */
1198 		while ((dp = readdir64(dirp)) != NULL) {
1199 			const char *name = dp->d_name;
1200 			if (name[0] == '.' &&
1201 			    (name[1] == 0 || (name[1] == '.' && name[2] == 0)))
1202 				continue;
1203 
1204 			slice = zfs_alloc(hdl, sizeof (rdsk_node_t));
1205 			slice->rn_name = zfs_strdup(hdl, name);
1206 			slice->rn_avl = &slice_cache;
1207 			slice->rn_dfd = dfd;
1208 			slice->rn_hdl = hdl;
1209 			slice->rn_nozpool = B_FALSE;
1210 			avl_add(&slice_cache, slice);
1211 		}
1212 		/*
1213 		 * create a thread pool to do all of this in parallel;
1214 		 * rn_nozpool is not protected, so this is racy in that
1215 		 * multiple tasks could decide that the same slice can
1216 		 * not hold a zpool, which is benign.  Also choose
1217 		 * double the number of processors; we hold a lot of
1218 		 * locks in the kernel, so going beyond this doesn't
1219 		 * buy us much.
1220 		 */
1221 		t = tpool_create(1, 2 * sysconf(_SC_NPROCESSORS_ONLN),
1222 		    0, NULL);
1223 		for (slice = avl_first(&slice_cache); slice;
1224 		    (slice = avl_walk(&slice_cache, slice,
1225 		    AVL_AFTER)))
1226 			(void) tpool_dispatch(t, zpool_open_func, slice);
1227 		tpool_wait(t);
1228 		tpool_destroy(t);
1229 
1230 		cookie = NULL;
1231 		while ((slice = avl_destroy_nodes(&slice_cache,
1232 		    &cookie)) != NULL) {
1233 			if (slice->rn_config != NULL && !config_failed) {
1234 				nvlist_t *config = slice->rn_config;
1235 				boolean_t matched = B_TRUE;
1236 
1237 				if (iarg->poolname != NULL) {
1238 					char *pname;
1239 
1240 					matched = nvlist_lookup_string(config,
1241 					    ZPOOL_CONFIG_POOL_NAME,
1242 					    &pname) == 0 &&
1243 					    strcmp(iarg->poolname, pname) == 0;
1244 				} else if (iarg->guid != 0) {
1245 					uint64_t this_guid;
1246 
1247 					matched = nvlist_lookup_uint64(config,
1248 					    ZPOOL_CONFIG_POOL_GUID,
1249 					    &this_guid) == 0 &&
1250 					    iarg->guid == this_guid;
1251 				}
1252 				if (!matched) {
1253 					nvlist_free(config);
1254 				} else {
1255 					/*
1256 					 * use the non-raw path for the config
1257 					 */
1258 					(void) strlcpy(end, slice->rn_name,
1259 					    pathleft);
1260 					if (add_config(hdl, &pools, path,
1261 					    config) != 0)
1262 						config_failed = B_TRUE;
1263 				}
1264 			}
1265 			free(slice->rn_name);
1266 			free(slice);
1267 		}
1268 		avl_destroy(&slice_cache);
1269 
1270 		(void) closedir(dirp);
1271 
1272 		if (config_failed)
1273 			goto error;
1274 	}
1275 
1276 	ret = get_configs(hdl, &pools, iarg->can_be_active);
1277 
1278 error:
1279 	for (pe = pools.pools; pe != NULL; pe = penext) {
1280 		penext = pe->pe_next;
1281 		for (ve = pe->pe_vdevs; ve != NULL; ve = venext) {
1282 			venext = ve->ve_next;
1283 			for (ce = ve->ve_configs; ce != NULL; ce = cenext) {
1284 				cenext = ce->ce_next;
1285 				nvlist_free(ce->ce_config);
1286 				free(ce);
1287 			}
1288 			free(ve);
1289 		}
1290 		free(pe);
1291 	}
1292 
1293 	for (ne = pools.names; ne != NULL; ne = nenext) {
1294 		nenext = ne->ne_next;
1295 		free(ne->ne_name);
1296 		free(ne);
1297 	}
1298 
1299 	return (ret);
1300 }
1301 
1302 nvlist_t *
zpool_find_import(libzfs_handle_t * hdl,int argc,char ** argv)1303 zpool_find_import(libzfs_handle_t *hdl, int argc, char **argv)
1304 {
1305 	importargs_t iarg = { 0 };
1306 
1307 	iarg.paths = argc;
1308 	iarg.path = argv;
1309 
1310 	return (zpool_find_import_impl(hdl, &iarg));
1311 }
1312 
1313 /*
1314  * Given a cache file, return the contents as a list of importable pools.
1315  * poolname or guid (but not both) are provided by the caller when trying
1316  * to import a specific pool.
1317  */
1318 nvlist_t *
zpool_find_import_cached(libzfs_handle_t * hdl,const char * cachefile,char * poolname,uint64_t guid)1319 zpool_find_import_cached(libzfs_handle_t *hdl, const char *cachefile,
1320     char *poolname, uint64_t guid)
1321 {
1322 	char *buf;
1323 	int fd;
1324 	struct stat64 statbuf;
1325 	nvlist_t *raw, *src, *dst;
1326 	nvlist_t *pools;
1327 	nvpair_t *elem;
1328 	char *name;
1329 	uint64_t this_guid;
1330 	boolean_t active;
1331 
1332 	verify(poolname == NULL || guid == 0);
1333 
1334 	if ((fd = open(cachefile, O_RDONLY)) < 0) {
1335 		zfs_error_aux(hdl, "%s", strerror(errno));
1336 		(void) zfs_error(hdl, EZFS_BADCACHE,
1337 		    dgettext(TEXT_DOMAIN, "failed to open cache file"));
1338 		return (NULL);
1339 	}
1340 
1341 	if (fstat64(fd, &statbuf) != 0) {
1342 		zfs_error_aux(hdl, "%s", strerror(errno));
1343 		(void) close(fd);
1344 		(void) zfs_error(hdl, EZFS_BADCACHE,
1345 		    dgettext(TEXT_DOMAIN, "failed to get size of cache file"));
1346 		return (NULL);
1347 	}
1348 
1349 	if ((buf = zfs_alloc(hdl, statbuf.st_size)) == NULL) {
1350 		(void) close(fd);
1351 		return (NULL);
1352 	}
1353 
1354 	if (read(fd, buf, statbuf.st_size) != statbuf.st_size) {
1355 		(void) close(fd);
1356 		free(buf);
1357 		(void) zfs_error(hdl, EZFS_BADCACHE,
1358 		    dgettext(TEXT_DOMAIN,
1359 		    "failed to read cache file contents"));
1360 		return (NULL);
1361 	}
1362 
1363 	(void) close(fd);
1364 
1365 	if (nvlist_unpack(buf, statbuf.st_size, &raw, 0) != 0) {
1366 		free(buf);
1367 		(void) zfs_error(hdl, EZFS_BADCACHE,
1368 		    dgettext(TEXT_DOMAIN,
1369 		    "invalid or corrupt cache file contents"));
1370 		return (NULL);
1371 	}
1372 
1373 	free(buf);
1374 
1375 	/*
1376 	 * Go through and get the current state of the pools and refresh their
1377 	 * state.
1378 	 */
1379 	if (nvlist_alloc(&pools, 0, 0) != 0) {
1380 		(void) no_memory(hdl);
1381 		nvlist_free(raw);
1382 		return (NULL);
1383 	}
1384 
1385 	elem = NULL;
1386 	while ((elem = nvlist_next_nvpair(raw, elem)) != NULL) {
1387 		src = fnvpair_value_nvlist(elem);
1388 
1389 		name = fnvlist_lookup_string(src, ZPOOL_CONFIG_POOL_NAME);
1390 		if (poolname != NULL && strcmp(poolname, name) != 0)
1391 			continue;
1392 
1393 		this_guid = fnvlist_lookup_uint64(src, ZPOOL_CONFIG_POOL_GUID);
1394 		if (guid != 0 && guid != this_guid)
1395 			continue;
1396 
1397 		if (pool_active(hdl, name, this_guid, &active) != 0) {
1398 			nvlist_free(raw);
1399 			nvlist_free(pools);
1400 			return (NULL);
1401 		}
1402 
1403 		if (active)
1404 			continue;
1405 
1406 		if ((dst = refresh_config(hdl, src)) == NULL) {
1407 			nvlist_free(raw);
1408 			nvlist_free(pools);
1409 			return (NULL);
1410 		}
1411 
1412 		if (nvlist_add_nvlist(pools, nvpair_name(elem), dst) != 0) {
1413 			(void) no_memory(hdl);
1414 			nvlist_free(dst);
1415 			nvlist_free(raw);
1416 			nvlist_free(pools);
1417 			return (NULL);
1418 		}
1419 		nvlist_free(dst);
1420 	}
1421 
1422 	nvlist_free(raw);
1423 	return (pools);
1424 }
1425 
1426 static int
name_or_guid_exists(zpool_handle_t * zhp,void * data)1427 name_or_guid_exists(zpool_handle_t *zhp, void *data)
1428 {
1429 	importargs_t *import = data;
1430 	int found = 0;
1431 
1432 	if (import->poolname != NULL) {
1433 		char *pool_name;
1434 
1435 		verify(nvlist_lookup_string(zhp->zpool_config,
1436 		    ZPOOL_CONFIG_POOL_NAME, &pool_name) == 0);
1437 		if (strcmp(pool_name, import->poolname) == 0)
1438 			found = 1;
1439 	} else {
1440 		uint64_t pool_guid;
1441 
1442 		verify(nvlist_lookup_uint64(zhp->zpool_config,
1443 		    ZPOOL_CONFIG_POOL_GUID, &pool_guid) == 0);
1444 		if (pool_guid == import->guid)
1445 			found = 1;
1446 	}
1447 
1448 	zpool_close(zhp);
1449 	return (found);
1450 }
1451 
1452 nvlist_t *
zpool_search_import(libzfs_handle_t * hdl,importargs_t * import)1453 zpool_search_import(libzfs_handle_t *hdl, importargs_t *import)
1454 {
1455 	verify(import->poolname == NULL || import->guid == 0);
1456 
1457 	if (import->unique)
1458 		import->exists = zpool_iter(hdl, name_or_guid_exists, import);
1459 
1460 	if (import->cachefile != NULL)
1461 		return (zpool_find_import_cached(hdl, import->cachefile,
1462 		    import->poolname, import->guid));
1463 
1464 	return (zpool_find_import_impl(hdl, import));
1465 }
1466 
1467 boolean_t
find_guid(nvlist_t * nv,uint64_t guid)1468 find_guid(nvlist_t *nv, uint64_t guid)
1469 {
1470 	uint64_t tmp;
1471 	nvlist_t **child;
1472 	uint_t c, children;
1473 
1474 	verify(nvlist_lookup_uint64(nv, ZPOOL_CONFIG_GUID, &tmp) == 0);
1475 	if (tmp == guid)
1476 		return (B_TRUE);
1477 
1478 	if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
1479 	    &child, &children) == 0) {
1480 		for (c = 0; c < children; c++)
1481 			if (find_guid(child[c], guid))
1482 				return (B_TRUE);
1483 	}
1484 
1485 	return (B_FALSE);
1486 }
1487 
1488 typedef struct aux_cbdata {
1489 	const char	*cb_type;
1490 	uint64_t	cb_guid;
1491 	zpool_handle_t	*cb_zhp;
1492 } aux_cbdata_t;
1493 
1494 static int
find_aux(zpool_handle_t * zhp,void * data)1495 find_aux(zpool_handle_t *zhp, void *data)
1496 {
1497 	aux_cbdata_t *cbp = data;
1498 	nvlist_t **list;
1499 	uint_t i, count;
1500 	uint64_t guid;
1501 	nvlist_t *nvroot;
1502 
1503 	verify(nvlist_lookup_nvlist(zhp->zpool_config, ZPOOL_CONFIG_VDEV_TREE,
1504 	    &nvroot) == 0);
1505 
1506 	if (nvlist_lookup_nvlist_array(nvroot, cbp->cb_type,
1507 	    &list, &count) == 0) {
1508 		for (i = 0; i < count; i++) {
1509 			verify(nvlist_lookup_uint64(list[i],
1510 			    ZPOOL_CONFIG_GUID, &guid) == 0);
1511 			if (guid == cbp->cb_guid) {
1512 				cbp->cb_zhp = zhp;
1513 				return (1);
1514 			}
1515 		}
1516 	}
1517 
1518 	zpool_close(zhp);
1519 	return (0);
1520 }
1521 
1522 /*
1523  * Determines if the pool is in use.  If so, it returns true and the state of
1524  * the pool as well as the name of the pool.  Both strings are allocated and
1525  * must be freed by the caller.
1526  */
1527 int
zpool_in_use(libzfs_handle_t * hdl,int fd,pool_state_t * state,char ** namestr,boolean_t * inuse)1528 zpool_in_use(libzfs_handle_t *hdl, int fd, pool_state_t *state, char **namestr,
1529     boolean_t *inuse)
1530 {
1531 	nvlist_t *config;
1532 	char *name;
1533 	boolean_t ret;
1534 	uint64_t guid, vdev_guid;
1535 	zpool_handle_t *zhp;
1536 	nvlist_t *pool_config;
1537 	uint64_t stateval, isspare;
1538 	aux_cbdata_t cb = { 0 };
1539 	boolean_t isactive;
1540 
1541 	*inuse = B_FALSE;
1542 
1543 	if (zpool_read_label(fd, &config) != 0) {
1544 		(void) no_memory(hdl);
1545 		return (-1);
1546 	}
1547 
1548 	if (config == NULL)
1549 		return (0);
1550 
1551 	verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_STATE,
1552 	    &stateval) == 0);
1553 	verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID,
1554 	    &vdev_guid) == 0);
1555 
1556 	if (stateval != POOL_STATE_SPARE && stateval != POOL_STATE_L2CACHE) {
1557 		verify(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
1558 		    &name) == 0);
1559 		verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
1560 		    &guid) == 0);
1561 	}
1562 
1563 	switch (stateval) {
1564 	case POOL_STATE_EXPORTED:
1565 		/*
1566 		 * A pool with an exported state may in fact be imported
1567 		 * read-only, so check the in-core state to see if it's
1568 		 * active and imported read-only.  If it is, set
1569 		 * its state to active.
1570 		 */
1571 		if (pool_active(hdl, name, guid, &isactive) == 0 && isactive &&
1572 		    (zhp = zpool_open_canfail(hdl, name)) != NULL) {
1573 			if (zpool_get_prop_int(zhp, ZPOOL_PROP_READONLY, NULL))
1574 				stateval = POOL_STATE_ACTIVE;
1575 
1576 			/*
1577 			 * All we needed the zpool handle for is the
1578 			 * readonly prop check.
1579 			 */
1580 			zpool_close(zhp);
1581 		}
1582 
1583 		ret = B_TRUE;
1584 		break;
1585 
1586 	case POOL_STATE_ACTIVE:
1587 		/*
1588 		 * For an active pool, we have to determine if it's really part
1589 		 * of a currently active pool (in which case the pool will exist
1590 		 * and the guid will be the same), or whether it's part of an
1591 		 * active pool that was disconnected without being explicitly
1592 		 * exported.
1593 		 */
1594 		if (pool_active(hdl, name, guid, &isactive) != 0) {
1595 			nvlist_free(config);
1596 			return (-1);
1597 		}
1598 
1599 		if (isactive) {
1600 			/*
1601 			 * Because the device may have been removed while
1602 			 * offlined, we only report it as active if the vdev is
1603 			 * still present in the config.  Otherwise, pretend like
1604 			 * it's not in use.
1605 			 */
1606 			if ((zhp = zpool_open_canfail(hdl, name)) != NULL &&
1607 			    (pool_config = zpool_get_config(zhp, NULL))
1608 			    != NULL) {
1609 				nvlist_t *nvroot;
1610 
1611 				verify(nvlist_lookup_nvlist(pool_config,
1612 				    ZPOOL_CONFIG_VDEV_TREE, &nvroot) == 0);
1613 				ret = find_guid(nvroot, vdev_guid);
1614 			} else {
1615 				ret = B_FALSE;
1616 			}
1617 
1618 			/*
1619 			 * If this is an active spare within another pool, we
1620 			 * treat it like an unused hot spare.  This allows the
1621 			 * user to create a pool with a hot spare that currently
1622 			 * in use within another pool.  Since we return B_TRUE,
1623 			 * libdiskmgt will continue to prevent generic consumers
1624 			 * from using the device.
1625 			 */
1626 			if (ret && nvlist_lookup_uint64(config,
1627 			    ZPOOL_CONFIG_IS_SPARE, &isspare) == 0 && isspare)
1628 				stateval = POOL_STATE_SPARE;
1629 
1630 			if (zhp != NULL)
1631 				zpool_close(zhp);
1632 		} else {
1633 			stateval = POOL_STATE_POTENTIALLY_ACTIVE;
1634 			ret = B_TRUE;
1635 		}
1636 		break;
1637 
1638 	case POOL_STATE_SPARE:
1639 		/*
1640 		 * For a hot spare, it can be either definitively in use, or
1641 		 * potentially active.  To determine if it's in use, we iterate
1642 		 * over all pools in the system and search for one with a spare
1643 		 * with a matching guid.
1644 		 *
1645 		 * Due to the shared nature of spares, we don't actually report
1646 		 * the potentially active case as in use.  This means the user
1647 		 * can freely create pools on the hot spares of exported pools,
1648 		 * but to do otherwise makes the resulting code complicated, and
1649 		 * we end up having to deal with this case anyway.
1650 		 */
1651 		cb.cb_zhp = NULL;
1652 		cb.cb_guid = vdev_guid;
1653 		cb.cb_type = ZPOOL_CONFIG_SPARES;
1654 		if (zpool_iter(hdl, find_aux, &cb) == 1) {
1655 			name = (char *)zpool_get_name(cb.cb_zhp);
1656 			ret = B_TRUE;
1657 		} else {
1658 			ret = B_FALSE;
1659 		}
1660 		break;
1661 
1662 	case POOL_STATE_L2CACHE:
1663 
1664 		/*
1665 		 * Check if any pool is currently using this l2cache device.
1666 		 */
1667 		cb.cb_zhp = NULL;
1668 		cb.cb_guid = vdev_guid;
1669 		cb.cb_type = ZPOOL_CONFIG_L2CACHE;
1670 		if (zpool_iter(hdl, find_aux, &cb) == 1) {
1671 			name = (char *)zpool_get_name(cb.cb_zhp);
1672 			ret = B_TRUE;
1673 		} else {
1674 			ret = B_FALSE;
1675 		}
1676 		break;
1677 
1678 	default:
1679 		ret = B_FALSE;
1680 	}
1681 
1682 
1683 	if (ret) {
1684 		if ((*namestr = zfs_strdup(hdl, name)) == NULL) {
1685 			if (cb.cb_zhp)
1686 				zpool_close(cb.cb_zhp);
1687 			nvlist_free(config);
1688 			return (-1);
1689 		}
1690 		*state = (pool_state_t)stateval;
1691 	}
1692 
1693 	if (cb.cb_zhp)
1694 		zpool_close(cb.cb_zhp);
1695 
1696 	nvlist_free(config);
1697 	*inuse = ret;
1698 	return (0);
1699 }
1700