xref: /illumos-gate/usr/src/cmd/zpool/zpool_vdev.c (revision 80ab886d233f514d54c2a6bdeb9fdfd951bd6881)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 /*
29  * Functions to convert between a list of vdevs and an nvlist representing the
30  * configuration.  Each entry in the list can be one of:
31  *
32  * 	Device vdevs
33  * 		disk=(path=..., devid=...)
34  * 		file=(path=...)
35  *
36  * 	Group vdevs
37  * 		raidz=(...)
38  * 		mirror=(...)
39  *
40  * While the underlying implementation supports it, group vdevs cannot contain
41  * other group vdevs.  All userland verification of devices is contained within
42  * this file.  If successful, the nvlist returned can be passed directly to the
43  * kernel; we've done as much verification as possible in userland.
44  *
45  * The only function exported by this file is 'get_vdev_spec'.  The function
46  * performs several passes:
47  *
48  * 	1. Construct the vdev specification.  Performs syntax validation and
49  *         makes sure each device is valid.
50  * 	2. Check for devices in use.  Using libdiskmgt, makes sure that no
51  *         devices are also in use.  Some can be overridden using the 'force'
52  *         flag, others cannot.
53  * 	3. Check for replication errors if the 'force' flag is not specified.
54  *         validates that the replication level is consistent across the
55  *         entire pool.
56  * 	4. Label any whole disks with an EFI label.
57  */
58 
59 #include <assert.h>
60 #include <devid.h>
61 #include <errno.h>
62 #include <fcntl.h>
63 #include <libdiskmgt.h>
64 #include <libintl.h>
65 #include <libnvpair.h>
66 #include <stdio.h>
67 #include <string.h>
68 #include <unistd.h>
69 #include <sys/efi_partition.h>
70 #include <sys/stat.h>
71 #include <sys/vtoc.h>
72 #include <sys/mntent.h>
73 
74 #include <libzfs.h>
75 
76 #include "zpool_util.h"
77 
78 #define	DISK_ROOT	"/dev/dsk"
79 #define	RDISK_ROOT	"/dev/rdsk"
80 #define	BACKUP_SLICE	"s2"
81 
82 /*
83  * For any given vdev specification, we can have multiple errors.  The
84  * vdev_error() function keeps track of whether we have seen an error yet, and
85  * prints out a header if its the first error we've seen.
86  */
87 int error_seen;
88 int is_force;
89 
90 void
91 vdev_error(const char *fmt, ...)
92 {
93 	va_list ap;
94 
95 	if (!error_seen) {
96 		(void) fprintf(stderr, gettext("invalid vdev specification\n"));
97 		if (!is_force)
98 			(void) fprintf(stderr, gettext("use '-f' to override "
99 			    "the following errors:\n"));
100 		else
101 			(void) fprintf(stderr, gettext("the following errors "
102 			    "must be manually repaired:\n"));
103 		error_seen = TRUE;
104 	}
105 
106 	va_start(ap, fmt);
107 	(void) vfprintf(stderr, fmt, ap);
108 	va_end(ap);
109 }
110 
111 static void
112 libdiskmgt_error(int error)
113 {
114 	/*
115 	 * ENXIO is a valid error message if the device doesn't live in
116 	 * /dev/dsk.  Don't bother printing an error message in this case.
117 	 */
118 	if (error == ENXIO)
119 		return;
120 
121 	(void) fprintf(stderr, gettext("warning: device in use checking "
122 	    "failed: %s\n"), strerror(error));
123 }
124 
125 /*
126  * Validate a device, passing the bulk of the work off to libdiskmgt.
127  */
128 int
129 check_slice(const char *path, int force, int wholedisk)
130 {
131 	char *msg;
132 	int error = 0;
133 	int ret = 0;
134 
135 	if (dm_inuse((char *)path, &msg,
136 	    force ? DM_WHO_ZPOOL_FORCE : DM_WHO_ZPOOL, &error) || error) {
137 		if (error != 0) {
138 			libdiskmgt_error(error);
139 			return (0);
140 		} else {
141 			vdev_error("%s", msg);
142 			free(msg);
143 		}
144 
145 		ret = -1;
146 	}
147 
148 	/*
149 	 * If we're given a whole disk, ignore overlapping slices since we're
150 	 * about to label it anyway.
151 	 */
152 	error = 0;
153 	if (!wholedisk && !force &&
154 	    (dm_isoverlapping((char *)path, &msg, &error) || error)) {
155 		if (error != 0) {
156 			libdiskmgt_error(error);
157 			return (0);
158 		} else {
159 			vdev_error("%s overlaps with %s\n", path, msg);
160 			free(msg);
161 		}
162 
163 		ret = -1;
164 	}
165 
166 	return (ret);
167 }
168 
169 /*
170  * Validate a whole disk.  Iterate over all slices on the disk and make sure
171  * that none is in use by calling check_slice().
172  */
173 /* ARGSUSED */
174 int
175 check_disk(const char *name, dm_descriptor_t disk, int force)
176 {
177 	dm_descriptor_t *drive, *media, *slice;
178 	int err = 0;
179 	int i;
180 	int ret;
181 
182 	/*
183 	 * Get the drive associated with this disk.  This should never fail,
184 	 * because we already have an alias handle open for the device.
185 	 */
186 	if ((drive = dm_get_associated_descriptors(disk, DM_DRIVE,
187 	    &err)) == NULL || *drive == NULL) {
188 		if (err)
189 			libdiskmgt_error(err);
190 		return (0);
191 	}
192 
193 	if ((media = dm_get_associated_descriptors(*drive, DM_MEDIA,
194 	    &err)) == NULL) {
195 		dm_free_descriptors(drive);
196 		if (err)
197 			libdiskmgt_error(err);
198 		return (0);
199 	}
200 
201 	dm_free_descriptors(drive);
202 
203 	/*
204 	 * It is possible that the user has specified a removable media drive,
205 	 * and the media is not present.
206 	 */
207 	if (*media == NULL) {
208 		dm_free_descriptors(media);
209 		vdev_error(gettext("'%s' has no media in drive\n"), name);
210 		return (-1);
211 	}
212 
213 	if ((slice = dm_get_associated_descriptors(*media, DM_SLICE,
214 	    &err)) == NULL) {
215 		dm_free_descriptors(media);
216 		if (err)
217 			libdiskmgt_error(err);
218 		return (0);
219 	}
220 
221 	dm_free_descriptors(media);
222 
223 	ret = 0;
224 
225 	/*
226 	 * Iterate over all slices and report any errors.  We don't care about
227 	 * overlapping slices because we are using the whole disk.
228 	 */
229 	for (i = 0; slice[i] != NULL; i++) {
230 		if (check_slice(dm_get_name(slice[i], &err), force, TRUE) != 0)
231 			ret = -1;
232 	}
233 
234 	dm_free_descriptors(slice);
235 	return (ret);
236 }
237 
238 /*
239  * Validate a device.
240  */
241 int
242 check_device(const char *path, int force)
243 {
244 	dm_descriptor_t desc;
245 	int err;
246 	char *dev;
247 
248 	/*
249 	 * For whole disks, libdiskmgt does not include the leading dev path.
250 	 */
251 	dev = strrchr(path, '/');
252 	assert(dev != NULL);
253 	dev++;
254 	if ((desc = dm_get_descriptor_by_name(DM_ALIAS, dev, &err)) != NULL) {
255 		err = check_disk(path, desc, force);
256 		dm_free_descriptor(desc);
257 		return (err);
258 	}
259 
260 	return (check_slice(path, force, FALSE));
261 }
262 
263 /*
264  * Check that a file is valid.  All we can do in this case is check that it's
265  * not in use by another pool.
266  */
267 int
268 check_file(const char *file, int force)
269 {
270 	char  *name;
271 	int fd;
272 	int ret = 0;
273 	pool_state_t state;
274 
275 	if ((fd = open(file, O_RDONLY)) < 0)
276 		return (0);
277 
278 	if (zpool_in_use(fd, &state, &name)) {
279 		const char *desc;
280 
281 		switch (state) {
282 		case POOL_STATE_ACTIVE:
283 			desc = gettext("active");
284 			break;
285 
286 		case POOL_STATE_EXPORTED:
287 			desc = gettext("exported");
288 			break;
289 
290 		case POOL_STATE_POTENTIALLY_ACTIVE:
291 			desc = gettext("potentially active");
292 			break;
293 
294 		default:
295 			desc = gettext("unknown");
296 			break;
297 		}
298 
299 		if (state == POOL_STATE_ACTIVE || !force) {
300 			vdev_error(gettext("%s is part of %s pool '%s'\n"),
301 			    file, desc, name);
302 			ret = -1;
303 		}
304 
305 		free(name);
306 	}
307 
308 	(void) close(fd);
309 	return (ret);
310 }
311 
312 static int
313 is_whole_disk(const char *arg, struct stat64 *statbuf)
314 {
315 	char path[MAXPATHLEN];
316 
317 	(void) snprintf(path, sizeof (path), "%s%s", arg, BACKUP_SLICE);
318 	if (stat64(path, statbuf) == 0)
319 		return (TRUE);
320 
321 	return (FALSE);
322 }
323 
324 /*
325  * Create a leaf vdev.  Determine if this is a file or a device.  If it's a
326  * device, fill in the device id to make a complete nvlist.  Valid forms for a
327  * leaf vdev are:
328  *
329  * 	/dev/dsk/xxx	Complete disk path
330  * 	/xxx		Full path to file
331  * 	xxx		Shorthand for /dev/dsk/xxx
332  */
333 nvlist_t *
334 make_leaf_vdev(const char *arg)
335 {
336 	char path[MAXPATHLEN];
337 	struct stat64 statbuf;
338 	nvlist_t *vdev = NULL;
339 	char *type = NULL;
340 	int wholedisk = FALSE;
341 
342 	/*
343 	 * Determine what type of vdev this is, and put the full path into
344 	 * 'path'.  We detect whether this is a device of file afterwards by
345 	 * checking the st_mode of the file.
346 	 */
347 	if (arg[0] == '/') {
348 		/*
349 		 * Complete device or file path.  Exact type is determined by
350 		 * examining the file descriptor afterwards.
351 		 */
352 		if (is_whole_disk(arg, &statbuf)) {
353 			wholedisk = TRUE;
354 		} else if (stat64(arg, &statbuf) != 0) {
355 			(void) fprintf(stderr,
356 			    gettext("cannot open '%s': %s\n"),
357 			    arg, strerror(errno));
358 			return (NULL);
359 		}
360 
361 		(void) strlcpy(path, arg, sizeof (path));
362 	} else {
363 		/*
364 		 * This may be a short path for a device, or it could be total
365 		 * gibberish.  Check to see if it's a known device in
366 		 * /dev/dsk/.  As part of this check, see if we've been given a
367 		 * an entire disk (minus the slice number).
368 		 */
369 		(void) snprintf(path, sizeof (path), "%s/%s", DISK_ROOT,
370 		    arg);
371 		if (is_whole_disk(path, &statbuf)) {
372 			wholedisk = TRUE;
373 		} else if (stat64(path, &statbuf) != 0) {
374 			/*
375 			 * If we got ENOENT, then the user gave us
376 			 * gibberish, so try to direct them with a
377 			 * reasonable error message.  Otherwise,
378 			 * regurgitate strerror() since it's the best we
379 			 * can do.
380 			 */
381 			if (errno == ENOENT) {
382 				(void) fprintf(stderr,
383 				    gettext("cannot open '%s': no such "
384 				    "device in %s\n"), arg, DISK_ROOT);
385 				(void) fprintf(stderr,
386 				    gettext("must be a full path or "
387 				    "shorthand device name\n"));
388 				return (NULL);
389 			} else {
390 				(void) fprintf(stderr,
391 				    gettext("cannot open '%s': %s\n"),
392 				    path, strerror(errno));
393 				return (NULL);
394 			}
395 		}
396 	}
397 
398 	/*
399 	 * Determine whether this is a device or a file.
400 	 */
401 	if (S_ISBLK(statbuf.st_mode)) {
402 		type = VDEV_TYPE_DISK;
403 	} else if (S_ISREG(statbuf.st_mode)) {
404 		type = VDEV_TYPE_FILE;
405 	} else {
406 		(void) fprintf(stderr, gettext("cannot use '%s': must be a "
407 		    "block device or regular file\n"), path);
408 		return (NULL);
409 	}
410 
411 	/*
412 	 * Finally, we have the complete device or file, and we know that it is
413 	 * acceptable to use.  Construct the nvlist to describe this vdev.  All
414 	 * vdevs have a 'path' element, and devices also have a 'devid' element.
415 	 */
416 	verify(nvlist_alloc(&vdev, NV_UNIQUE_NAME, 0) == 0);
417 	verify(nvlist_add_string(vdev, ZPOOL_CONFIG_PATH, path) == 0);
418 	verify(nvlist_add_string(vdev, ZPOOL_CONFIG_TYPE, type) == 0);
419 	if (strcmp(type, VDEV_TYPE_DISK) == 0)
420 		verify(nvlist_add_uint64(vdev, ZPOOL_CONFIG_WHOLE_DISK,
421 		    (uint64_t)wholedisk) == 0);
422 
423 	/*
424 	 * For a whole disk, defer getting its devid until after labeling it.
425 	 */
426 	if (S_ISBLK(statbuf.st_mode) && !wholedisk) {
427 		/*
428 		 * Get the devid for the device.
429 		 */
430 		int fd;
431 		ddi_devid_t devid;
432 		char *minor = NULL, *devid_str = NULL;
433 
434 		if ((fd = open(path, O_RDONLY)) < 0) {
435 			(void) fprintf(stderr, gettext("cannot open '%s': "
436 			    "%s\n"), path, strerror(errno));
437 			nvlist_free(vdev);
438 			return (NULL);
439 		}
440 
441 		if (devid_get(fd, &devid) == 0) {
442 			if (devid_get_minor_name(fd, &minor) == 0 &&
443 			    (devid_str = devid_str_encode(devid, minor)) !=
444 			    NULL) {
445 				verify(nvlist_add_string(vdev,
446 				    ZPOOL_CONFIG_DEVID, devid_str) == 0);
447 			}
448 			if (devid_str != NULL)
449 				devid_str_free(devid_str);
450 			if (minor != NULL)
451 				devid_str_free(minor);
452 			devid_free(devid);
453 		}
454 
455 		(void) close(fd);
456 	}
457 
458 	return (vdev);
459 }
460 
461 /*
462  * Go through and verify the replication level of the pool is consistent.
463  * Performs the following checks:
464  *
465  * 	For the new spec, verifies that devices in mirrors and raidz are the
466  * 	same size.
467  *
468  * 	If the current configuration already has inconsistent replication
469  * 	levels, ignore any other potential problems in the new spec.
470  *
471  * 	Otherwise, make sure that the current spec (if there is one) and the new
472  * 	spec have consistent replication levels.
473  */
474 typedef struct replication_level {
475 	char	*type;
476 	int	level;
477 } replication_level_t;
478 
479 /*
480  * Given a list of toplevel vdevs, return the current replication level.  If
481  * the config is inconsistent, then NULL is returned.  If 'fatal' is set, then
482  * an error message will be displayed for each self-inconsistent vdev.
483  */
484 replication_level_t *
485 get_replication(nvlist_t *nvroot, int fatal)
486 {
487 	nvlist_t **top;
488 	uint_t t, toplevels;
489 	nvlist_t **child;
490 	uint_t c, children;
491 	nvlist_t *nv;
492 	char *type;
493 	replication_level_t lastrep, rep, *ret;
494 	int dontreport;
495 
496 	ret = safe_malloc(sizeof (replication_level_t));
497 
498 	verify(nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_CHILDREN,
499 	    &top, &toplevels) == 0);
500 
501 	lastrep.type = NULL;
502 	for (t = 0; t < toplevels; t++) {
503 		nv = top[t];
504 
505 		verify(nvlist_lookup_string(nv, ZPOOL_CONFIG_TYPE, &type) == 0);
506 
507 		if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
508 		    &child, &children) != 0) {
509 			/*
510 			 * This is a 'file' or 'disk' vdev.
511 			 */
512 			rep.type = type;
513 			rep.level = 1;
514 		} else {
515 			uint64_t vdev_size;
516 
517 			/*
518 			 * This is a mirror or RAID-Z vdev.  Go through and make
519 			 * sure the contents are all the same (files vs. disks),
520 			 * keeping track of the number of elements in the
521 			 * process.
522 			 *
523 			 * We also check that the size of each vdev (if it can
524 			 * be determined) is the same.
525 			 */
526 			rep.type = type;
527 			rep.level = 0;
528 
529 			/*
530 			 * The 'dontreport' variable indicatest that we've
531 			 * already reported an error for this spec, so don't
532 			 * bother doing it again.
533 			 */
534 			type = NULL;
535 			dontreport = 0;
536 			vdev_size = -1ULL;
537 			for (c = 0; c < children; c++) {
538 				nvlist_t *cnv = child[c];
539 				char *path;
540 				struct stat64 statbuf;
541 				uint64_t size = -1ULL;
542 				char *childtype;
543 				int fd, err;
544 
545 				rep.level++;
546 
547 				verify(nvlist_lookup_string(cnv,
548 				    ZPOOL_CONFIG_TYPE, &childtype) == 0);
549 				verify(nvlist_lookup_string(cnv,
550 				    ZPOOL_CONFIG_PATH, &path) == 0);
551 
552 				/*
553 				 * If we have a raidz/mirror that combines disks
554 				 * with files, report it as an error.
555 				 */
556 				if (!dontreport && type != NULL &&
557 				    strcmp(type, childtype) != 0) {
558 					if (ret != NULL)
559 						free(ret);
560 					ret = NULL;
561 					if (fatal)
562 						vdev_error(gettext(
563 						    "mismatched replication "
564 						    "level: %s contains both "
565 						    "files and devices\n"),
566 						    rep.type);
567 					else
568 						return (NULL);
569 					dontreport = TRUE;
570 				}
571 
572 				/*
573 				 * According to stat(2), the value of 'st_size'
574 				 * is undefined for block devices and character
575 				 * devices.  But there is no effective way to
576 				 * determine the real size in userland.
577 				 *
578 				 * Instead, we'll take advantage of an
579 				 * implementation detail of spec_size().  If the
580 				 * device is currently open, then we (should)
581 				 * return a valid size.
582 				 *
583 				 * If we still don't get a valid size (indicated
584 				 * by a size of 0 or MAXOFFSET_T), then ignore
585 				 * this device altogether.
586 				 */
587 				if ((fd = open(path, O_RDONLY)) >= 0) {
588 					err = fstat64(fd, &statbuf);
589 					(void) close(fd);
590 				} else {
591 					err = stat64(path, &statbuf);
592 				}
593 
594 				if (err != 0 ||
595 				    statbuf.st_size == 0 ||
596 				    statbuf.st_size == MAXOFFSET_T)
597 					continue;
598 
599 				size = statbuf.st_size;
600 
601 				/*
602 				 * Also check the size of each device.  If they
603 				 * differ, then report an error.
604 				 */
605 				if (!dontreport && vdev_size != -1ULL &&
606 				    size != vdev_size) {
607 					if (ret != NULL)
608 						free(ret);
609 					ret = NULL;
610 					if (fatal)
611 						vdev_error(gettext(
612 						    "%s contains devices of "
613 						    "different sizes\n"),
614 						    rep.type);
615 					else
616 						return (NULL);
617 					dontreport = TRUE;
618 				}
619 
620 				type = childtype;
621 				vdev_size = size;
622 			}
623 		}
624 
625 		/*
626 		 * At this point, we have the replication of the last toplevel
627 		 * vdev in 'rep'.  Compare it to 'lastrep' to see if its
628 		 * different.
629 		 */
630 		if (lastrep.type != NULL) {
631 			if (strcmp(lastrep.type, rep.type) != 0) {
632 				if (ret != NULL)
633 					free(ret);
634 				ret = NULL;
635 				if (fatal)
636 					vdev_error(gettext(
637 					    "mismatched replication "
638 					    "level: both %s and %s vdevs are "
639 					    "present\n"),
640 					    lastrep.type, rep.type);
641 				else
642 					return (NULL);
643 			} else if (lastrep.level != rep.level) {
644 				if (ret)
645 					free(ret);
646 				ret = NULL;
647 				if (fatal)
648 					vdev_error(gettext(
649 					    "mismatched replication "
650 					    "level: %d-way %s and %d-way %s "
651 					    "vdevs are present\n"),
652 					    lastrep.level, lastrep.type,
653 					    rep.level, rep.type);
654 				else
655 					return (NULL);
656 			}
657 		}
658 		lastrep = rep;
659 	}
660 
661 	if (ret != NULL) {
662 		ret->type = rep.type;
663 		ret->level = rep.level;
664 	}
665 
666 	return (ret);
667 }
668 
669 /*
670  * Check the replication level of the vdev spec against the current pool.  Calls
671  * get_replication() to make sure the new spec is self-consistent.  If the pool
672  * has a consistent replication level, then we ignore any errors.  Otherwise,
673  * report any difference between the two.
674  */
675 int
676 check_replication(nvlist_t *config, nvlist_t *newroot)
677 {
678 	replication_level_t *current = NULL, *new;
679 	int ret;
680 
681 	/*
682 	 * If we have a current pool configuration, check to see if it's
683 	 * self-consistent.  If not, simply return success.
684 	 */
685 	if (config != NULL) {
686 		nvlist_t *nvroot;
687 
688 		verify(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
689 		    &nvroot) == 0);
690 		if ((current = get_replication(nvroot, FALSE)) == NULL)
691 			return (0);
692 	}
693 
694 	/*
695 	 * Get the replication level of the new vdev spec, reporting any
696 	 * inconsistencies found.
697 	 */
698 	if ((new = get_replication(newroot, TRUE)) == NULL) {
699 		free(current);
700 		return (-1);
701 	}
702 
703 	/*
704 	 * Check to see if the new vdev spec matches the replication level of
705 	 * the current pool.
706 	 */
707 	ret = 0;
708 	if (current != NULL) {
709 		if (strcmp(current->type, new->type) != 0 ||
710 		    current->level != new->level) {
711 			vdev_error(gettext(
712 			    "mismatched replication level: pool uses %d-way %s "
713 			    "and new vdev uses %d-way %s\n"),
714 			    current->level, current->type, new->level,
715 			    new->type);
716 			ret = -1;
717 		}
718 	}
719 
720 	free(new);
721 	if (current != NULL)
722 		free(current);
723 
724 	return (ret);
725 }
726 
727 /*
728  * Label an individual disk.  The name provided is the short name, stripped of
729  * any leading /dev path.
730  */
731 int
732 label_disk(char *name)
733 {
734 	char path[MAXPATHLEN];
735 	struct dk_gpt *vtoc;
736 	int fd;
737 	size_t resv = 16384;
738 
739 	(void) snprintf(path, sizeof (path), "%s/%s%s", RDISK_ROOT, name,
740 	    BACKUP_SLICE);
741 
742 	if ((fd = open(path, O_RDWR | O_NDELAY)) < 0) {
743 		/*
744 		 * This shouldn't happen.  We've long since verified that this
745 		 * is a valid device.
746 		 */
747 		(void) fprintf(stderr, gettext("cannot open '%s': %s\n"),
748 		    path, strerror(errno));
749 		return (-1);
750 	}
751 
752 
753 	if (efi_alloc_and_init(fd, 9, &vtoc) != 0) {
754 		/*
755 		 * The only way this can fail is if we run out of memory, or we
756 		 * were unable to read the disk geometry.
757 		 */
758 		if (errno == ENOMEM)
759 			no_memory();
760 
761 		(void) fprintf(stderr, gettext("cannot label '%s': unable to "
762 		    "read disk geometry\n"), name);
763 		(void) close(fd);
764 		return (-1);
765 	}
766 
767 	vtoc->efi_parts[0].p_start = vtoc->efi_first_u_lba;
768 	vtoc->efi_parts[0].p_size = vtoc->efi_last_u_lba + 1 -
769 	    vtoc->efi_first_u_lba - resv;
770 
771 	/*
772 	 * Why we use V_USR: V_BACKUP confuses users, and is considered
773 	 * disposable by some EFI utilities (since EFI doesn't have a backup
774 	 * slice).  V_UNASSIGNED is supposed to be used only for zero size
775 	 * partitions, and efi_write() will fail if we use it.  V_ROOT, V_BOOT,
776 	 * etc. were all pretty specific.  V_USR is as close to reality as we
777 	 * can get, in the absence of V_OTHER.
778 	 */
779 	vtoc->efi_parts[0].p_tag = V_USR;
780 	(void) strcpy(vtoc->efi_parts[0].p_name, "zfs");
781 
782 	vtoc->efi_parts[8].p_start = vtoc->efi_last_u_lba + 1 - resv;
783 	vtoc->efi_parts[8].p_size = resv;
784 	vtoc->efi_parts[8].p_tag = V_RESERVED;
785 
786 	if (efi_write(fd, vtoc) != 0) {
787 		/*
788 		 * Currently, EFI labels are not supported for IDE disks, and it
789 		 * is likely that they will not be supported on other drives for
790 		 * some time.  Print out a helpful error message directing the
791 		 * user to manually label the disk and give a specific slice.
792 		 */
793 		(void) fprintf(stderr, gettext("cannot label '%s': failed to "
794 		    "write EFI label\n"), name);
795 		(void) fprintf(stderr, gettext("use fdisk(1M) to partition "
796 		    "the disk, and provide a specific slice\n"));
797 		(void) close(fd);
798 		return (-1);
799 	}
800 
801 	(void) close(fd);
802 	return (0);
803 }
804 
805 /*
806  * Go through and find any whole disks in the vdev specification, labelling them
807  * as appropriate.  When constructing the vdev spec, we were unable to open this
808  * device in order to provide a devid.  Now that we have labelled the disk and
809  * know that slice 0 is valid, we can construct the devid now.
810  *
811  * If the disk was already labelled with an EFI label, we will have gotten the
812  * devid already (because we were able to open the whole disk).  Otherwise, we
813  * need to get the devid after we label the disk.
814  */
815 int
816 make_disks(nvlist_t *nv)
817 {
818 	nvlist_t **child;
819 	uint_t c, children;
820 	char *type, *path, *diskname;
821 	char buf[MAXPATHLEN];
822 	uint64_t wholedisk;
823 	int fd;
824 	int ret;
825 	ddi_devid_t devid;
826 	char *minor = NULL, *devid_str = NULL;
827 
828 	verify(nvlist_lookup_string(nv, ZPOOL_CONFIG_TYPE, &type) == 0);
829 
830 	if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
831 	    &child, &children) != 0) {
832 
833 		if (strcmp(type, VDEV_TYPE_DISK) != 0)
834 			return (0);
835 
836 		/*
837 		 * We have a disk device.  Get the path to the device
838 		 * and see if its a whole disk by appending the backup
839 		 * slice and stat()ing the device.
840 		 */
841 		verify(nvlist_lookup_string(nv, ZPOOL_CONFIG_PATH, &path) == 0);
842 
843 		if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_WHOLE_DISK,
844 		    &wholedisk) != 0 || !wholedisk)
845 			return (0);
846 
847 		diskname = strrchr(path, '/');
848 		assert(diskname != NULL);
849 		diskname++;
850 		if (label_disk(diskname) != 0)
851 			return (-1);
852 
853 		/*
854 		 * Fill in the devid, now that we've labeled the disk.
855 		 */
856 		(void) snprintf(buf, sizeof (buf), "%ss0", path);
857 		if ((fd = open(buf, O_RDONLY)) < 0) {
858 			(void) fprintf(stderr,
859 			    gettext("cannot open '%s': %s\n"),
860 			    buf, strerror(errno));
861 			return (-1);
862 		}
863 
864 		if (devid_get(fd, &devid) == 0) {
865 			if (devid_get_minor_name(fd, &minor) == 0 &&
866 			    (devid_str = devid_str_encode(devid, minor)) !=
867 			    NULL) {
868 				verify(nvlist_add_string(nv,
869 				    ZPOOL_CONFIG_DEVID, devid_str) == 0);
870 			}
871 			if (devid_str != NULL)
872 				devid_str_free(devid_str);
873 			if (minor != NULL)
874 				devid_str_free(minor);
875 			devid_free(devid);
876 		}
877 
878 		/*
879 		 * Update the path to refer to the 's0' slice.  The presence of
880 		 * the 'whole_disk' field indicates to the CLI that we should
881 		 * chop off the slice number when displaying the device in
882 		 * future output.
883 		 */
884 		verify(nvlist_add_string(nv, ZPOOL_CONFIG_PATH, buf) == 0);
885 
886 		(void) close(fd);
887 
888 		return (0);
889 	}
890 
891 	for (c = 0; c < children; c++)
892 		if ((ret = make_disks(child[c])) != 0)
893 			return (ret);
894 
895 	return (0);
896 }
897 
898 /*
899  * Go through and find any devices that are in use.  We rely on libdiskmgt for
900  * the majority of this task.
901  */
902 int
903 check_in_use(nvlist_t *nv, int force)
904 {
905 	nvlist_t **child;
906 	uint_t c, children;
907 	char *type, *path;
908 	int ret;
909 
910 	verify(nvlist_lookup_string(nv, ZPOOL_CONFIG_TYPE, &type) == 0);
911 
912 	if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
913 	    &child, &children) != 0) {
914 
915 		verify(nvlist_lookup_string(nv, ZPOOL_CONFIG_PATH, &path) == 0);
916 
917 		if (strcmp(type, VDEV_TYPE_DISK) == 0)
918 			ret = check_device(path, force);
919 
920 		if (strcmp(type, VDEV_TYPE_FILE) == 0)
921 			ret = check_file(path, force);
922 
923 		return (ret);
924 	}
925 
926 	for (c = 0; c < children; c++)
927 		if ((ret = check_in_use(child[c], force)) != 0)
928 			return (ret);
929 
930 	return (0);
931 }
932 
933 /*
934  * Construct a syntactically valid vdev specification,
935  * and ensure that all devices and files exist and can be opened.
936  * Note: we don't bother freeing anything in the error paths
937  * because the program is just going to exit anyway.
938  */
939 nvlist_t *
940 construct_spec(int argc, char **argv)
941 {
942 	nvlist_t *nvroot, *nv, **top;
943 	int t, toplevels;
944 
945 	top = NULL;
946 	toplevels = 0;
947 
948 	while (argc > 0) {
949 		nv = NULL;
950 
951 		/*
952 		 * If it's a mirror or raidz, the subsequent arguments are
953 		 * its leaves -- until we encounter the next mirror or raidz.
954 		 */
955 		if (strcmp(argv[0], VDEV_TYPE_MIRROR) == 0 ||
956 		    strcmp(argv[0], VDEV_TYPE_RAIDZ) == 0) {
957 
958 			char *type = argv[0];
959 			nvlist_t **child = NULL;
960 			int children = 0;
961 			int c;
962 
963 			for (c = 1; c < argc; c++) {
964 				if (strcmp(argv[c], VDEV_TYPE_MIRROR) == 0 ||
965 				    strcmp(argv[c], VDEV_TYPE_RAIDZ) == 0)
966 					break;
967 				children++;
968 				child = realloc(child,
969 				    children * sizeof (nvlist_t *));
970 				if (child == NULL)
971 					no_memory();
972 				if ((nv = make_leaf_vdev(argv[c])) == NULL)
973 					return (NULL);
974 				child[children - 1] = nv;
975 			}
976 
977 			argc -= c;
978 			argv += c;
979 
980 			/*
981 			 * Mirrors and RAID-Z devices require at least
982 			 * two components.
983 			 */
984 			if (children < 2) {
985 				(void) fprintf(stderr,
986 				    gettext("invalid vdev specification: "
987 				    "%s requires at least 2 devices\n"), type);
988 				return (NULL);
989 			}
990 
991 			verify(nvlist_alloc(&nv, NV_UNIQUE_NAME, 0) == 0);
992 			verify(nvlist_add_string(nv, ZPOOL_CONFIG_TYPE,
993 			    type) == 0);
994 			verify(nvlist_add_nvlist_array(nv,
995 			    ZPOOL_CONFIG_CHILDREN, child, children) == 0);
996 
997 			for (c = 0; c < children; c++)
998 				nvlist_free(child[c]);
999 			free(child);
1000 		} else {
1001 			/*
1002 			 * We have a device.  Pass off to make_leaf_vdev() to
1003 			 * construct the appropriate nvlist describing the vdev.
1004 			 */
1005 			if ((nv = make_leaf_vdev(argv[0])) == NULL)
1006 				return (NULL);
1007 			argc--;
1008 			argv++;
1009 		}
1010 
1011 		toplevels++;
1012 		top = realloc(top, toplevels * sizeof (nvlist_t *));
1013 		if (top == NULL)
1014 			no_memory();
1015 		top[toplevels - 1] = nv;
1016 	}
1017 
1018 	/*
1019 	 * Finally, create nvroot and add all top-level vdevs to it.
1020 	 */
1021 	verify(nvlist_alloc(&nvroot, NV_UNIQUE_NAME, 0) == 0);
1022 	verify(nvlist_add_string(nvroot, ZPOOL_CONFIG_TYPE,
1023 	    VDEV_TYPE_ROOT) == 0);
1024 	verify(nvlist_add_nvlist_array(nvroot, ZPOOL_CONFIG_CHILDREN,
1025 	    top, toplevels) == 0);
1026 
1027 	for (t = 0; t < toplevels; t++)
1028 		nvlist_free(top[t]);
1029 	free(top);
1030 
1031 	return (nvroot);
1032 }
1033 
1034 /*
1035  * Get and validate the contents of the given vdev specification.  This ensures
1036  * that the nvlist returned is well-formed, that all the devices exist, and that
1037  * they are not currently in use by any other known consumer.  The 'poolconfig'
1038  * parameter is the current configuration of the pool when adding devices
1039  * existing pool, and is used to perform additional checks, such as changing the
1040  * replication level of the pool.  It can be 'NULL' to indicate that this is a
1041  * new pool.  The 'force' flag controls whether devices should be forcefully
1042  * added, even if they appear in use.
1043  */
1044 nvlist_t *
1045 make_root_vdev(nvlist_t *poolconfig, int force, int check_rep,
1046     int argc, char **argv)
1047 {
1048 	nvlist_t *newroot;
1049 
1050 	is_force = force;
1051 
1052 	/*
1053 	 * Construct the vdev specification.  If this is successful, we know
1054 	 * that we have a valid specification, and that all devices can be
1055 	 * opened.
1056 	 */
1057 	if ((newroot = construct_spec(argc, argv)) == NULL)
1058 		return (NULL);
1059 
1060 	/*
1061 	 * Validate each device to make sure that its not shared with another
1062 	 * subsystem.  We do this even if 'force' is set, because there are some
1063 	 * uses (such as a dedicated dump device) that even '-f' cannot
1064 	 * override.
1065 	 */
1066 	if (check_in_use(newroot, force) != 0) {
1067 		nvlist_free(newroot);
1068 		return (NULL);
1069 	}
1070 
1071 	/*
1072 	 * Check the replication level of the given vdevs and report any errors
1073 	 * found.  We include the existing pool spec, if any, as we need to
1074 	 * catch changes against the existing replication level.
1075 	 */
1076 	if (check_rep && check_replication(poolconfig, newroot) != 0) {
1077 		nvlist_free(newroot);
1078 		return (NULL);
1079 	}
1080 
1081 	/*
1082 	 * Run through the vdev specification and label any whole disks found.
1083 	 */
1084 	if (make_disks(newroot) != 0) {
1085 		nvlist_free(newroot);
1086 		return (NULL);
1087 	}
1088 
1089 	return (newroot);
1090 }
1091