xref: /freebsd/sys/contrib/openzfs/lib/libefi/rdwr_efi.c (revision 5def4c47d4bd90b209b9b4a4ba9faec15846d8fd)
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 (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
24  * Copyright 2012 Nexenta Systems, Inc.  All rights reserved.
25  * Copyright (c) 2018 by Delphix. All rights reserved.
26  */
27 
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <errno.h>
31 #include <string.h>
32 #include <strings.h>
33 #include <unistd.h>
34 #include <uuid/uuid.h>
35 #include <zlib.h>
36 #include <libintl.h>
37 #include <sys/types.h>
38 #include <sys/dkio.h>
39 #include <sys/vtoc.h>
40 #include <sys/mhd.h>
41 #include <sys/param.h>
42 #include <sys/dktp/fdisk.h>
43 #include <sys/efi_partition.h>
44 #include <sys/byteorder.h>
45 #include <sys/vdev_disk.h>
46 #include <linux/fs.h>
47 #include <linux/blkpg.h>
48 
49 static struct uuid_to_ptag {
50 	struct uuid	uuid;
51 } conversion_array[] = {
52 	{ EFI_UNUSED },
53 	{ EFI_BOOT },
54 	{ EFI_ROOT },
55 	{ EFI_SWAP },
56 	{ EFI_USR },
57 	{ EFI_BACKUP },
58 	{ EFI_UNUSED },		/* STAND is never used */
59 	{ EFI_VAR },
60 	{ EFI_HOME },
61 	{ EFI_ALTSCTR },
62 	{ EFI_UNUSED },		/* CACHE (cachefs) is never used */
63 	{ EFI_RESERVED },
64 	{ EFI_SYSTEM },
65 	{ EFI_LEGACY_MBR },
66 	{ EFI_SYMC_PUB },
67 	{ EFI_SYMC_CDS },
68 	{ EFI_MSFT_RESV },
69 	{ EFI_DELL_BASIC },
70 	{ EFI_DELL_RAID },
71 	{ EFI_DELL_SWAP },
72 	{ EFI_DELL_LVM },
73 	{ EFI_DELL_RESV },
74 	{ EFI_AAPL_HFS },
75 	{ EFI_AAPL_UFS },
76 	{ EFI_FREEBSD_BOOT },
77 	{ EFI_FREEBSD_SWAP },
78 	{ EFI_FREEBSD_UFS },
79 	{ EFI_FREEBSD_VINUM },
80 	{ EFI_FREEBSD_ZFS },
81 	{ EFI_BIOS_BOOT },
82 	{ EFI_INTC_RS },
83 	{ EFI_SNE_BOOT },
84 	{ EFI_LENOVO_BOOT },
85 	{ EFI_MSFT_LDMM },
86 	{ EFI_MSFT_LDMD },
87 	{ EFI_MSFT_RE },
88 	{ EFI_IBM_GPFS },
89 	{ EFI_MSFT_STORAGESPACES },
90 	{ EFI_HPQ_DATA },
91 	{ EFI_HPQ_SVC },
92 	{ EFI_RHT_DATA },
93 	{ EFI_RHT_HOME },
94 	{ EFI_RHT_SRV },
95 	{ EFI_RHT_DMCRYPT },
96 	{ EFI_RHT_LUKS },
97 	{ EFI_FREEBSD_DISKLABEL },
98 	{ EFI_AAPL_RAID },
99 	{ EFI_AAPL_RAIDOFFLINE },
100 	{ EFI_AAPL_BOOT },
101 	{ EFI_AAPL_LABEL },
102 	{ EFI_AAPL_TVRECOVERY },
103 	{ EFI_AAPL_CORESTORAGE },
104 	{ EFI_NETBSD_SWAP },
105 	{ EFI_NETBSD_FFS },
106 	{ EFI_NETBSD_LFS },
107 	{ EFI_NETBSD_RAID },
108 	{ EFI_NETBSD_CAT },
109 	{ EFI_NETBSD_CRYPT },
110 	{ EFI_GOOG_KERN },
111 	{ EFI_GOOG_ROOT },
112 	{ EFI_GOOG_RESV },
113 	{ EFI_HAIKU_BFS },
114 	{ EFI_MIDNIGHTBSD_BOOT },
115 	{ EFI_MIDNIGHTBSD_DATA },
116 	{ EFI_MIDNIGHTBSD_SWAP },
117 	{ EFI_MIDNIGHTBSD_UFS },
118 	{ EFI_MIDNIGHTBSD_VINUM },
119 	{ EFI_MIDNIGHTBSD_ZFS },
120 	{ EFI_CEPH_JOURNAL },
121 	{ EFI_CEPH_DMCRYPTJOURNAL },
122 	{ EFI_CEPH_OSD },
123 	{ EFI_CEPH_DMCRYPTOSD },
124 	{ EFI_CEPH_CREATE },
125 	{ EFI_CEPH_DMCRYPTCREATE },
126 	{ EFI_OPENBSD_DISKLABEL },
127 	{ EFI_BBRY_QNX },
128 	{ EFI_BELL_PLAN9 },
129 	{ EFI_VMW_KCORE },
130 	{ EFI_VMW_VMFS },
131 	{ EFI_VMW_RESV },
132 	{ EFI_RHT_ROOTX86 },
133 	{ EFI_RHT_ROOTAMD64 },
134 	{ EFI_RHT_ROOTARM },
135 	{ EFI_RHT_ROOTARM64 },
136 	{ EFI_ACRONIS_SECUREZONE },
137 	{ EFI_ONIE_BOOT },
138 	{ EFI_ONIE_CONFIG },
139 	{ EFI_IBM_PPRPBOOT },
140 	{ EFI_FREEDESKTOP_BOOT }
141 };
142 
143 int efi_debug = 0;
144 
145 static int efi_read(int, struct dk_gpt *);
146 
147 /*
148  * Return a 32-bit CRC of the contents of the buffer.  Pre-and-post
149  * one's conditioning will be handled by crc32() internally.
150  */
151 static uint32_t
152 efi_crc32(const unsigned char *buf, unsigned int size)
153 {
154 	uint32_t crc = crc32(0, Z_NULL, 0);
155 
156 	crc = crc32(crc, buf, size);
157 
158 	return (crc);
159 }
160 
161 static int
162 read_disk_info(int fd, diskaddr_t *capacity, uint_t *lbsize)
163 {
164 	int sector_size;
165 	unsigned long long capacity_size;
166 
167 	if (ioctl(fd, BLKSSZGET, &sector_size) < 0)
168 		return (-1);
169 
170 	if (ioctl(fd, BLKGETSIZE64, &capacity_size) < 0)
171 		return (-1);
172 
173 	*lbsize = (uint_t)sector_size;
174 	*capacity = (diskaddr_t)(capacity_size / sector_size);
175 
176 	return (0);
177 }
178 
179 /*
180  * Return back the device name associated with the file descriptor. The
181  * caller is responsible for freeing the memory associated with the
182  * returned string.
183  */
184 static char *
185 efi_get_devname(int fd)
186 {
187 	char path[32];
188 
189 	/*
190 	 * The libefi API only provides the open fd and not the file path.
191 	 * To handle this realpath(3) is used to resolve the block device
192 	 * name from /proc/self/fd/<fd>.
193 	 */
194 	(void) snprintf(path, sizeof (path), "/proc/self/fd/%d", fd);
195 	return (realpath(path, NULL));
196 }
197 
198 static int
199 efi_get_info(int fd, struct dk_cinfo *dki_info)
200 {
201 	char *dev_path;
202 	int rval = 0;
203 
204 	memset(dki_info, 0, sizeof (*dki_info));
205 
206 	/*
207 	 * The simplest way to get the partition number under linux is
208 	 * to parse it out of the /dev/<disk><partition> block device name.
209 	 * The kernel creates this using the partition number when it
210 	 * populates /dev/ so it may be trusted.  The tricky bit here is
211 	 * that the naming convention is based on the block device type.
212 	 * So we need to take this in to account when parsing out the
213 	 * partition information.  Aside from the partition number we collect
214 	 * some additional device info.
215 	 */
216 	dev_path = efi_get_devname(fd);
217 	if (dev_path == NULL)
218 		goto error;
219 
220 	if ((strncmp(dev_path, "/dev/sd", 7) == 0)) {
221 		strcpy(dki_info->dki_cname, "sd");
222 		dki_info->dki_ctype = DKC_SCSI_CCS;
223 		rval = sscanf(dev_path, "/dev/%[a-zA-Z]%hu",
224 		    dki_info->dki_dname,
225 		    &dki_info->dki_partition);
226 	} else if ((strncmp(dev_path, "/dev/hd", 7) == 0)) {
227 		strcpy(dki_info->dki_cname, "hd");
228 		dki_info->dki_ctype = DKC_DIRECT;
229 		rval = sscanf(dev_path, "/dev/%[a-zA-Z]%hu",
230 		    dki_info->dki_dname,
231 		    &dki_info->dki_partition);
232 	} else if ((strncmp(dev_path, "/dev/md", 7) == 0)) {
233 		strcpy(dki_info->dki_cname, "pseudo");
234 		dki_info->dki_ctype = DKC_MD;
235 		strcpy(dki_info->dki_dname, "md");
236 		rval = sscanf(dev_path, "/dev/md%[0-9]p%hu",
237 		    dki_info->dki_dname + 2,
238 		    &dki_info->dki_partition);
239 	} else if ((strncmp(dev_path, "/dev/vd", 7) == 0)) {
240 		strcpy(dki_info->dki_cname, "vd");
241 		dki_info->dki_ctype = DKC_MD;
242 		rval = sscanf(dev_path, "/dev/%[a-zA-Z]%hu",
243 		    dki_info->dki_dname,
244 		    &dki_info->dki_partition);
245 	} else if ((strncmp(dev_path, "/dev/xvd", 8) == 0)) {
246 		strcpy(dki_info->dki_cname, "xvd");
247 		dki_info->dki_ctype = DKC_MD;
248 		rval = sscanf(dev_path, "/dev/%[a-zA-Z]%hu",
249 		    dki_info->dki_dname,
250 		    &dki_info->dki_partition);
251 	} else if ((strncmp(dev_path, "/dev/zd", 7) == 0)) {
252 		strcpy(dki_info->dki_cname, "zd");
253 		dki_info->dki_ctype = DKC_MD;
254 		strcpy(dki_info->dki_dname, "zd");
255 		rval = sscanf(dev_path, "/dev/zd%[0-9]p%hu",
256 		    dki_info->dki_dname + 2,
257 		    &dki_info->dki_partition);
258 	} else if ((strncmp(dev_path, "/dev/dm-", 8) == 0)) {
259 		strcpy(dki_info->dki_cname, "pseudo");
260 		dki_info->dki_ctype = DKC_VBD;
261 		strcpy(dki_info->dki_dname, "dm-");
262 		rval = sscanf(dev_path, "/dev/dm-%[0-9]p%hu",
263 		    dki_info->dki_dname + 3,
264 		    &dki_info->dki_partition);
265 	} else if ((strncmp(dev_path, "/dev/ram", 8) == 0)) {
266 		strcpy(dki_info->dki_cname, "pseudo");
267 		dki_info->dki_ctype = DKC_PCMCIA_MEM;
268 		strcpy(dki_info->dki_dname, "ram");
269 		rval = sscanf(dev_path, "/dev/ram%[0-9]p%hu",
270 		    dki_info->dki_dname + 3,
271 		    &dki_info->dki_partition);
272 	} else if ((strncmp(dev_path, "/dev/loop", 9) == 0)) {
273 		strcpy(dki_info->dki_cname, "pseudo");
274 		dki_info->dki_ctype = DKC_VBD;
275 		strcpy(dki_info->dki_dname, "loop");
276 		rval = sscanf(dev_path, "/dev/loop%[0-9]p%hu",
277 		    dki_info->dki_dname + 4,
278 		    &dki_info->dki_partition);
279 	} else if ((strncmp(dev_path, "/dev/nvme", 9) == 0)) {
280 		strcpy(dki_info->dki_cname, "nvme");
281 		dki_info->dki_ctype = DKC_SCSI_CCS;
282 		strcpy(dki_info->dki_dname, "nvme");
283 		(void) sscanf(dev_path, "/dev/nvme%[0-9]",
284 		    dki_info->dki_dname + 4);
285 		size_t controller_length = strlen(
286 		    dki_info->dki_dname);
287 		strcpy(dki_info->dki_dname + controller_length,
288 		    "n");
289 		rval = sscanf(dev_path,
290 		    "/dev/nvme%*[0-9]n%[0-9]p%hu",
291 		    dki_info->dki_dname + controller_length + 1,
292 		    &dki_info->dki_partition);
293 	} else {
294 		strcpy(dki_info->dki_dname, "unknown");
295 		strcpy(dki_info->dki_cname, "unknown");
296 		dki_info->dki_ctype = DKC_UNKNOWN;
297 	}
298 
299 	switch (rval) {
300 	case 0:
301 		errno = EINVAL;
302 		goto error;
303 	case 1:
304 		dki_info->dki_partition = 0;
305 	}
306 
307 	free(dev_path);
308 
309 	return (0);
310 error:
311 	if (efi_debug)
312 		(void) fprintf(stderr, "DKIOCINFO errno 0x%x\n", errno);
313 
314 	switch (errno) {
315 	case EIO:
316 		return (VT_EIO);
317 	case EINVAL:
318 		return (VT_EINVAL);
319 	default:
320 		return (VT_ERROR);
321 	}
322 }
323 
324 /*
325  * the number of blocks the EFI label takes up (round up to nearest
326  * block)
327  */
328 #define	NBLOCKS(p, l)	(1 + ((((p) * (int)sizeof (efi_gpe_t))  + \
329 				((l) - 1)) / (l)))
330 /* number of partitions -- limited by what we can malloc */
331 #define	MAX_PARTS	((4294967295UL - sizeof (struct dk_gpt)) / \
332 			    sizeof (struct dk_part))
333 
334 int
335 efi_alloc_and_init(int fd, uint32_t nparts, struct dk_gpt **vtoc)
336 {
337 	diskaddr_t	capacity = 0;
338 	uint_t		lbsize = 0;
339 	uint_t		nblocks;
340 	size_t		length;
341 	struct dk_gpt	*vptr;
342 	struct uuid	uuid;
343 	struct dk_cinfo	dki_info;
344 
345 	if (read_disk_info(fd, &capacity, &lbsize) != 0)
346 		return (-1);
347 
348 	if (efi_get_info(fd, &dki_info) != 0)
349 		return (-1);
350 
351 	if (dki_info.dki_partition != 0)
352 		return (-1);
353 
354 	if ((dki_info.dki_ctype == DKC_PCMCIA_MEM) ||
355 	    (dki_info.dki_ctype == DKC_VBD) ||
356 	    (dki_info.dki_ctype == DKC_UNKNOWN))
357 		return (-1);
358 
359 	nblocks = NBLOCKS(nparts, lbsize);
360 	if ((nblocks * lbsize) < EFI_MIN_ARRAY_SIZE + lbsize) {
361 		/* 16K plus one block for the GPT */
362 		nblocks = EFI_MIN_ARRAY_SIZE / lbsize + 1;
363 	}
364 
365 	if (nparts > MAX_PARTS) {
366 		if (efi_debug) {
367 			(void) fprintf(stderr,
368 			"the maximum number of partitions supported is %lu\n",
369 			    MAX_PARTS);
370 		}
371 		return (-1);
372 	}
373 
374 	length = sizeof (struct dk_gpt) +
375 	    sizeof (struct dk_part) * (nparts - 1);
376 
377 	vptr = calloc(1, length);
378 	if (vptr == NULL)
379 		return (-1);
380 
381 	*vtoc = vptr;
382 
383 	vptr->efi_version = EFI_VERSION_CURRENT;
384 	vptr->efi_lbasize = lbsize;
385 	vptr->efi_nparts = nparts;
386 	/*
387 	 * add one block here for the PMBR; on disks with a 512 byte
388 	 * block size and 128 or fewer partitions, efi_first_u_lba
389 	 * should work out to "34"
390 	 */
391 	vptr->efi_first_u_lba = nblocks + 1;
392 	vptr->efi_last_lba = capacity - 1;
393 	vptr->efi_altern_lba = capacity -1;
394 	vptr->efi_last_u_lba = vptr->efi_last_lba - nblocks;
395 
396 	(void) uuid_generate((uchar_t *)&uuid);
397 	UUID_LE_CONVERT(vptr->efi_disk_uguid, uuid);
398 	return (0);
399 }
400 
401 /*
402  * Read EFI - return partition number upon success.
403  */
404 int
405 efi_alloc_and_read(int fd, struct dk_gpt **vtoc)
406 {
407 	int			rval;
408 	uint32_t		nparts;
409 	int			length;
410 	struct dk_gpt		*vptr;
411 
412 	/* figure out the number of entries that would fit into 16K */
413 	nparts = EFI_MIN_ARRAY_SIZE / sizeof (efi_gpe_t);
414 	length = (int) sizeof (struct dk_gpt) +
415 	    (int) sizeof (struct dk_part) * (nparts - 1);
416 	vptr = calloc(1, length);
417 
418 	if (vptr == NULL)
419 		return (VT_ERROR);
420 
421 	vptr->efi_nparts = nparts;
422 	rval = efi_read(fd, vptr);
423 
424 	if ((rval == VT_EINVAL) && vptr->efi_nparts > nparts) {
425 		void *tmp;
426 		length = (int) sizeof (struct dk_gpt) +
427 		    (int) sizeof (struct dk_part) * (vptr->efi_nparts - 1);
428 		nparts = vptr->efi_nparts;
429 		if ((tmp = realloc(vptr, length)) == NULL) {
430 			/* cppcheck-suppress doubleFree */
431 			free(vptr);
432 			*vtoc = NULL;
433 			return (VT_ERROR);
434 		} else {
435 			vptr = tmp;
436 			rval = efi_read(fd, vptr);
437 		}
438 	}
439 
440 	if (rval < 0) {
441 		if (efi_debug) {
442 			(void) fprintf(stderr,
443 			    "read of EFI table failed, rval=%d\n", rval);
444 		}
445 		free(vptr);
446 		*vtoc = NULL;
447 	} else {
448 		*vtoc = vptr;
449 	}
450 
451 	return (rval);
452 }
453 
454 static int
455 efi_ioctl(int fd, int cmd, dk_efi_t *dk_ioc)
456 {
457 	void *data = dk_ioc->dki_data;
458 	int error;
459 	diskaddr_t capacity;
460 	uint_t lbsize;
461 
462 	/*
463 	 * When the IO is not being performed in kernel as an ioctl we need
464 	 * to know the sector size so we can seek to the proper byte offset.
465 	 */
466 	if (read_disk_info(fd, &capacity, &lbsize) == -1) {
467 		if (efi_debug)
468 			fprintf(stderr, "unable to read disk info: %d", errno);
469 
470 		errno = EIO;
471 		return (-1);
472 	}
473 
474 	switch (cmd) {
475 	case DKIOCGETEFI:
476 		if (lbsize == 0) {
477 			if (efi_debug)
478 				(void) fprintf(stderr, "DKIOCGETEFI assuming "
479 				    "LBA %d bytes\n", DEV_BSIZE);
480 
481 			lbsize = DEV_BSIZE;
482 		}
483 
484 		error = lseek(fd, dk_ioc->dki_lba * lbsize, SEEK_SET);
485 		if (error == -1) {
486 			if (efi_debug)
487 				(void) fprintf(stderr, "DKIOCGETEFI lseek "
488 				    "error: %d\n", errno);
489 			return (error);
490 		}
491 
492 		error = read(fd, data, dk_ioc->dki_length);
493 		if (error == -1) {
494 			if (efi_debug)
495 				(void) fprintf(stderr, "DKIOCGETEFI read "
496 				    "error: %d\n", errno);
497 			return (error);
498 		}
499 
500 		if (error != dk_ioc->dki_length) {
501 			if (efi_debug)
502 				(void) fprintf(stderr, "DKIOCGETEFI short "
503 				    "read of %d bytes\n", error);
504 			errno = EIO;
505 			return (-1);
506 		}
507 		error = 0;
508 		break;
509 
510 	case DKIOCSETEFI:
511 		if (lbsize == 0) {
512 			if (efi_debug)
513 				(void) fprintf(stderr, "DKIOCSETEFI unknown "
514 				    "LBA size\n");
515 			errno = EIO;
516 			return (-1);
517 		}
518 
519 		error = lseek(fd, dk_ioc->dki_lba * lbsize, SEEK_SET);
520 		if (error == -1) {
521 			if (efi_debug)
522 				(void) fprintf(stderr, "DKIOCSETEFI lseek "
523 				    "error: %d\n", errno);
524 			return (error);
525 		}
526 
527 		error = write(fd, data, dk_ioc->dki_length);
528 		if (error == -1) {
529 			if (efi_debug)
530 				(void) fprintf(stderr, "DKIOCSETEFI write "
531 				    "error: %d\n", errno);
532 			return (error);
533 		}
534 
535 		if (error != dk_ioc->dki_length) {
536 			if (efi_debug)
537 				(void) fprintf(stderr, "DKIOCSETEFI short "
538 				    "write of %d bytes\n", error);
539 			errno = EIO;
540 			return (-1);
541 		}
542 
543 		/* Sync the new EFI table to disk */
544 		error = fsync(fd);
545 		if (error == -1)
546 			return (error);
547 
548 		/* Ensure any local disk cache is also flushed */
549 		if (ioctl(fd, BLKFLSBUF, 0) == -1)
550 			return (error);
551 
552 		error = 0;
553 		break;
554 
555 	default:
556 		if (efi_debug)
557 			(void) fprintf(stderr, "unsupported ioctl()\n");
558 
559 		errno = EIO;
560 		return (-1);
561 	}
562 
563 	return (error);
564 }
565 
566 int
567 efi_rescan(int fd)
568 {
569 	int retry = 10;
570 	int error;
571 
572 	/* Notify the kernel a devices partition table has been updated */
573 	while ((error = ioctl(fd, BLKRRPART)) != 0) {
574 		if ((--retry == 0) || (errno != EBUSY)) {
575 			(void) fprintf(stderr, "the kernel failed to rescan "
576 			    "the partition table: %d\n", errno);
577 			return (-1);
578 		}
579 		usleep(50000);
580 	}
581 
582 	return (0);
583 }
584 
585 static int
586 check_label(int fd, dk_efi_t *dk_ioc)
587 {
588 	efi_gpt_t		*efi;
589 	uint_t			crc;
590 
591 	if (efi_ioctl(fd, DKIOCGETEFI, dk_ioc) == -1) {
592 		switch (errno) {
593 		case EIO:
594 			return (VT_EIO);
595 		default:
596 			return (VT_ERROR);
597 		}
598 	}
599 	efi = dk_ioc->dki_data;
600 	if (efi->efi_gpt_Signature != LE_64(EFI_SIGNATURE)) {
601 		if (efi_debug)
602 			(void) fprintf(stderr,
603 			    "Bad EFI signature: 0x%llx != 0x%llx\n",
604 			    (long long)efi->efi_gpt_Signature,
605 			    (long long)LE_64(EFI_SIGNATURE));
606 		return (VT_EINVAL);
607 	}
608 
609 	/*
610 	 * check CRC of the header; the size of the header should
611 	 * never be larger than one block
612 	 */
613 	crc = efi->efi_gpt_HeaderCRC32;
614 	efi->efi_gpt_HeaderCRC32 = 0;
615 	len_t headerSize = (len_t)LE_32(efi->efi_gpt_HeaderSize);
616 
617 	if (headerSize < EFI_MIN_LABEL_SIZE || headerSize > EFI_LABEL_SIZE) {
618 		if (efi_debug)
619 			(void) fprintf(stderr,
620 			    "Invalid EFI HeaderSize %llu.  Assuming %d.\n",
621 			    headerSize, EFI_MIN_LABEL_SIZE);
622 	}
623 
624 	if ((headerSize > dk_ioc->dki_length) ||
625 	    crc != LE_32(efi_crc32((unsigned char *)efi, headerSize))) {
626 		if (efi_debug)
627 			(void) fprintf(stderr,
628 			    "Bad EFI CRC: 0x%x != 0x%x\n",
629 			    crc, LE_32(efi_crc32((unsigned char *)efi,
630 			    headerSize)));
631 		return (VT_EINVAL);
632 	}
633 
634 	return (0);
635 }
636 
637 static int
638 efi_read(int fd, struct dk_gpt *vtoc)
639 {
640 	int			i, j;
641 	int			label_len;
642 	int			rval = 0;
643 	int			md_flag = 0;
644 	int			vdc_flag = 0;
645 	diskaddr_t		capacity = 0;
646 	uint_t			lbsize = 0;
647 	struct dk_minfo		disk_info;
648 	dk_efi_t		dk_ioc;
649 	efi_gpt_t		*efi;
650 	efi_gpe_t		*efi_parts;
651 	struct dk_cinfo		dki_info;
652 	uint32_t		user_length;
653 	boolean_t		legacy_label = B_FALSE;
654 
655 	/*
656 	 * get the partition number for this file descriptor.
657 	 */
658 	if ((rval = efi_get_info(fd, &dki_info)) != 0)
659 		return (rval);
660 
661 	if ((strncmp(dki_info.dki_cname, "pseudo", 7) == 0) &&
662 	    (strncmp(dki_info.dki_dname, "md", 3) == 0)) {
663 		md_flag++;
664 	} else if ((strncmp(dki_info.dki_cname, "vdc", 4) == 0) &&
665 	    (strncmp(dki_info.dki_dname, "vdc", 4) == 0)) {
666 		/*
667 		 * The controller and drive name "vdc" (virtual disk client)
668 		 * indicates a LDoms virtual disk.
669 		 */
670 		vdc_flag++;
671 	}
672 
673 	/* get the LBA size */
674 	if (read_disk_info(fd, &capacity, &lbsize) == -1) {
675 		if (efi_debug) {
676 			(void) fprintf(stderr,
677 			    "unable to read disk info: %d",
678 			    errno);
679 		}
680 		return (VT_EINVAL);
681 	}
682 
683 	disk_info.dki_lbsize = lbsize;
684 	disk_info.dki_capacity = capacity;
685 
686 	if (disk_info.dki_lbsize == 0) {
687 		if (efi_debug) {
688 			(void) fprintf(stderr,
689 			    "efi_read: assuming LBA 512 bytes\n");
690 		}
691 		disk_info.dki_lbsize = DEV_BSIZE;
692 	}
693 	/*
694 	 * Read the EFI GPT to figure out how many partitions we need
695 	 * to deal with.
696 	 */
697 	dk_ioc.dki_lba = 1;
698 	if (NBLOCKS(vtoc->efi_nparts, disk_info.dki_lbsize) < 34) {
699 		label_len = EFI_MIN_ARRAY_SIZE + disk_info.dki_lbsize;
700 	} else {
701 		label_len = vtoc->efi_nparts * (int) sizeof (efi_gpe_t) +
702 		    disk_info.dki_lbsize;
703 		if (label_len % disk_info.dki_lbsize) {
704 			/* pad to physical sector size */
705 			label_len += disk_info.dki_lbsize;
706 			label_len &= ~(disk_info.dki_lbsize - 1);
707 		}
708 	}
709 
710 	if (posix_memalign((void **)&dk_ioc.dki_data,
711 	    disk_info.dki_lbsize, label_len))
712 		return (VT_ERROR);
713 
714 	memset(dk_ioc.dki_data, 0, label_len);
715 	dk_ioc.dki_length = disk_info.dki_lbsize;
716 	user_length = vtoc->efi_nparts;
717 	efi = dk_ioc.dki_data;
718 	if (md_flag) {
719 		dk_ioc.dki_length = label_len;
720 		if (efi_ioctl(fd, DKIOCGETEFI, &dk_ioc) == -1) {
721 			switch (errno) {
722 			case EIO:
723 				return (VT_EIO);
724 			default:
725 				return (VT_ERROR);
726 			}
727 		}
728 	} else if ((rval = check_label(fd, &dk_ioc)) == VT_EINVAL) {
729 		/*
730 		 * No valid label here; try the alternate. Note that here
731 		 * we just read GPT header and save it into dk_ioc.data,
732 		 * Later, we will read GUID partition entry array if we
733 		 * can get valid GPT header.
734 		 */
735 
736 		/*
737 		 * This is a workaround for legacy systems. In the past, the
738 		 * last sector of SCSI disk was invisible on x86 platform. At
739 		 * that time, backup label was saved on the next to the last
740 		 * sector. It is possible for users to move a disk from previous
741 		 * solaris system to present system. Here, we attempt to search
742 		 * legacy backup EFI label first.
743 		 */
744 		dk_ioc.dki_lba = disk_info.dki_capacity - 2;
745 		dk_ioc.dki_length = disk_info.dki_lbsize;
746 		rval = check_label(fd, &dk_ioc);
747 		if (rval == VT_EINVAL) {
748 			/*
749 			 * we didn't find legacy backup EFI label, try to
750 			 * search backup EFI label in the last block.
751 			 */
752 			dk_ioc.dki_lba = disk_info.dki_capacity - 1;
753 			dk_ioc.dki_length = disk_info.dki_lbsize;
754 			rval = check_label(fd, &dk_ioc);
755 			if (rval == 0) {
756 				legacy_label = B_TRUE;
757 				if (efi_debug)
758 					(void) fprintf(stderr,
759 					    "efi_read: primary label corrupt; "
760 					    "using EFI backup label located on"
761 					    " the last block\n");
762 			}
763 		} else {
764 			if ((efi_debug) && (rval == 0))
765 				(void) fprintf(stderr, "efi_read: primary label"
766 				    " corrupt; using legacy EFI backup label "
767 				    " located on the next to last block\n");
768 		}
769 
770 		if (rval == 0) {
771 			dk_ioc.dki_lba = LE_64(efi->efi_gpt_PartitionEntryLBA);
772 			vtoc->efi_flags |= EFI_GPT_PRIMARY_CORRUPT;
773 			vtoc->efi_nparts =
774 			    LE_32(efi->efi_gpt_NumberOfPartitionEntries);
775 			/*
776 			 * Partition tables are between backup GPT header
777 			 * table and ParitionEntryLBA (the starting LBA of
778 			 * the GUID partition entries array). Now that we
779 			 * already got valid GPT header and saved it in
780 			 * dk_ioc.dki_data, we try to get GUID partition
781 			 * entry array here.
782 			 */
783 			/* LINTED */
784 			dk_ioc.dki_data = (efi_gpt_t *)((char *)dk_ioc.dki_data
785 			    + disk_info.dki_lbsize);
786 			if (legacy_label)
787 				dk_ioc.dki_length = disk_info.dki_capacity - 1 -
788 				    dk_ioc.dki_lba;
789 			else
790 				dk_ioc.dki_length = disk_info.dki_capacity - 2 -
791 				    dk_ioc.dki_lba;
792 			dk_ioc.dki_length *= disk_info.dki_lbsize;
793 			if (dk_ioc.dki_length >
794 			    ((len_t)label_len - sizeof (*dk_ioc.dki_data))) {
795 				rval = VT_EINVAL;
796 			} else {
797 				/*
798 				 * read GUID partition entry array
799 				 */
800 				rval = efi_ioctl(fd, DKIOCGETEFI, &dk_ioc);
801 			}
802 		}
803 
804 	} else if (rval == 0) {
805 
806 		dk_ioc.dki_lba = LE_64(efi->efi_gpt_PartitionEntryLBA);
807 		/* LINTED */
808 		dk_ioc.dki_data = (efi_gpt_t *)((char *)dk_ioc.dki_data
809 		    + disk_info.dki_lbsize);
810 		dk_ioc.dki_length = label_len - disk_info.dki_lbsize;
811 		rval = efi_ioctl(fd, DKIOCGETEFI, &dk_ioc);
812 
813 	} else if (vdc_flag && rval == VT_ERROR && errno == EINVAL) {
814 		/*
815 		 * When the device is a LDoms virtual disk, the DKIOCGETEFI
816 		 * ioctl can fail with EINVAL if the virtual disk backend
817 		 * is a ZFS volume serviced by a domain running an old version
818 		 * of Solaris. This is because the DKIOCGETEFI ioctl was
819 		 * initially incorrectly implemented for a ZFS volume and it
820 		 * expected the GPT and GPE to be retrieved with a single ioctl.
821 		 * So we try to read the GPT and the GPE using that old style
822 		 * ioctl.
823 		 */
824 		dk_ioc.dki_lba = 1;
825 		dk_ioc.dki_length = label_len;
826 		rval = check_label(fd, &dk_ioc);
827 	}
828 
829 	if (rval < 0) {
830 		free(efi);
831 		return (rval);
832 	}
833 
834 	/* LINTED -- always longlong aligned */
835 	efi_parts = (efi_gpe_t *)(((char *)efi) + disk_info.dki_lbsize);
836 
837 	/*
838 	 * Assemble this into a "dk_gpt" struct for easier
839 	 * digestibility by applications.
840 	 */
841 	vtoc->efi_version = LE_32(efi->efi_gpt_Revision);
842 	vtoc->efi_nparts = LE_32(efi->efi_gpt_NumberOfPartitionEntries);
843 	vtoc->efi_part_size = LE_32(efi->efi_gpt_SizeOfPartitionEntry);
844 	vtoc->efi_lbasize = disk_info.dki_lbsize;
845 	vtoc->efi_last_lba = disk_info.dki_capacity - 1;
846 	vtoc->efi_first_u_lba = LE_64(efi->efi_gpt_FirstUsableLBA);
847 	vtoc->efi_last_u_lba = LE_64(efi->efi_gpt_LastUsableLBA);
848 	vtoc->efi_altern_lba = LE_64(efi->efi_gpt_AlternateLBA);
849 	UUID_LE_CONVERT(vtoc->efi_disk_uguid, efi->efi_gpt_DiskGUID);
850 
851 	/*
852 	 * If the array the user passed in is too small, set the length
853 	 * to what it needs to be and return
854 	 */
855 	if (user_length < vtoc->efi_nparts) {
856 		return (VT_EINVAL);
857 	}
858 
859 	for (i = 0; i < vtoc->efi_nparts; i++) {
860 
861 		UUID_LE_CONVERT(vtoc->efi_parts[i].p_guid,
862 		    efi_parts[i].efi_gpe_PartitionTypeGUID);
863 
864 		for (j = 0;
865 		    j < sizeof (conversion_array)
866 		    / sizeof (struct uuid_to_ptag); j++) {
867 
868 			if (bcmp(&vtoc->efi_parts[i].p_guid,
869 			    &conversion_array[j].uuid,
870 			    sizeof (struct uuid)) == 0) {
871 				vtoc->efi_parts[i].p_tag = j;
872 				break;
873 			}
874 		}
875 		if (vtoc->efi_parts[i].p_tag == V_UNASSIGNED)
876 			continue;
877 		vtoc->efi_parts[i].p_flag =
878 		    LE_16(efi_parts[i].efi_gpe_Attributes.PartitionAttrs);
879 		vtoc->efi_parts[i].p_start =
880 		    LE_64(efi_parts[i].efi_gpe_StartingLBA);
881 		vtoc->efi_parts[i].p_size =
882 		    LE_64(efi_parts[i].efi_gpe_EndingLBA) -
883 		    vtoc->efi_parts[i].p_start + 1;
884 		for (j = 0; j < EFI_PART_NAME_LEN; j++) {
885 			vtoc->efi_parts[i].p_name[j] =
886 			    (uchar_t)LE_16(
887 			    efi_parts[i].efi_gpe_PartitionName[j]);
888 		}
889 
890 		UUID_LE_CONVERT(vtoc->efi_parts[i].p_uguid,
891 		    efi_parts[i].efi_gpe_UniquePartitionGUID);
892 	}
893 	free(efi);
894 
895 	return (dki_info.dki_partition);
896 }
897 
898 /* writes a "protective" MBR */
899 static int
900 write_pmbr(int fd, struct dk_gpt *vtoc)
901 {
902 	dk_efi_t	dk_ioc;
903 	struct mboot	mb;
904 	uchar_t		*cp;
905 	diskaddr_t	size_in_lba;
906 	uchar_t		*buf;
907 	int		len;
908 
909 	len = (vtoc->efi_lbasize == 0) ? sizeof (mb) : vtoc->efi_lbasize;
910 	if (posix_memalign((void **)&buf, len, len))
911 		return (VT_ERROR);
912 
913 	/*
914 	 * Preserve any boot code and disk signature if the first block is
915 	 * already an MBR.
916 	 */
917 	memset(buf, 0, len);
918 	dk_ioc.dki_lba = 0;
919 	dk_ioc.dki_length = len;
920 	/* LINTED -- always longlong aligned */
921 	dk_ioc.dki_data = (efi_gpt_t *)buf;
922 	if (efi_ioctl(fd, DKIOCGETEFI, &dk_ioc) == -1) {
923 		(void) memcpy(&mb, buf, sizeof (mb));
924 		bzero(&mb, sizeof (mb));
925 		mb.signature = LE_16(MBB_MAGIC);
926 	} else {
927 		(void) memcpy(&mb, buf, sizeof (mb));
928 		if (mb.signature != LE_16(MBB_MAGIC)) {
929 			bzero(&mb, sizeof (mb));
930 			mb.signature = LE_16(MBB_MAGIC);
931 		}
932 	}
933 
934 	bzero(&mb.parts, sizeof (mb.parts));
935 	cp = (uchar_t *)&mb.parts[0];
936 	/* bootable or not */
937 	*cp++ = 0;
938 	/* beginning CHS; 0xffffff if not representable */
939 	*cp++ = 0xff;
940 	*cp++ = 0xff;
941 	*cp++ = 0xff;
942 	/* OS type */
943 	*cp++ = EFI_PMBR;
944 	/* ending CHS; 0xffffff if not representable */
945 	*cp++ = 0xff;
946 	*cp++ = 0xff;
947 	*cp++ = 0xff;
948 	/* starting LBA: 1 (little endian format) by EFI definition */
949 	*cp++ = 0x01;
950 	*cp++ = 0x00;
951 	*cp++ = 0x00;
952 	*cp++ = 0x00;
953 	/* ending LBA: last block on the disk (little endian format) */
954 	size_in_lba = vtoc->efi_last_lba;
955 	if (size_in_lba < 0xffffffff) {
956 		*cp++ = (size_in_lba & 0x000000ff);
957 		*cp++ = (size_in_lba & 0x0000ff00) >> 8;
958 		*cp++ = (size_in_lba & 0x00ff0000) >> 16;
959 		*cp++ = (size_in_lba & 0xff000000) >> 24;
960 	} else {
961 		*cp++ = 0xff;
962 		*cp++ = 0xff;
963 		*cp++ = 0xff;
964 		*cp++ = 0xff;
965 	}
966 
967 	(void) memcpy(buf, &mb, sizeof (mb));
968 	/* LINTED -- always longlong aligned */
969 	dk_ioc.dki_data = (efi_gpt_t *)buf;
970 	dk_ioc.dki_lba = 0;
971 	dk_ioc.dki_length = len;
972 	if (efi_ioctl(fd, DKIOCSETEFI, &dk_ioc) == -1) {
973 		free(buf);
974 		switch (errno) {
975 		case EIO:
976 			return (VT_EIO);
977 		case EINVAL:
978 			return (VT_EINVAL);
979 		default:
980 			return (VT_ERROR);
981 		}
982 	}
983 	free(buf);
984 	return (0);
985 }
986 
987 /* make sure the user specified something reasonable */
988 static int
989 check_input(struct dk_gpt *vtoc)
990 {
991 	int			resv_part = -1;
992 	int			i, j;
993 	diskaddr_t		istart, jstart, isize, jsize, endsect;
994 
995 	/*
996 	 * Sanity-check the input (make sure no partitions overlap)
997 	 */
998 	for (i = 0; i < vtoc->efi_nparts; i++) {
999 		/* It can't be unassigned and have an actual size */
1000 		if ((vtoc->efi_parts[i].p_tag == V_UNASSIGNED) &&
1001 		    (vtoc->efi_parts[i].p_size != 0)) {
1002 			if (efi_debug) {
1003 				(void) fprintf(stderr, "partition %d is "
1004 				    "\"unassigned\" but has a size of %llu",
1005 				    i, vtoc->efi_parts[i].p_size);
1006 			}
1007 			return (VT_EINVAL);
1008 		}
1009 		if (vtoc->efi_parts[i].p_tag == V_UNASSIGNED) {
1010 			if (uuid_is_null((uchar_t *)&vtoc->efi_parts[i].p_guid))
1011 				continue;
1012 			/* we have encountered an unknown uuid */
1013 			vtoc->efi_parts[i].p_tag = 0xff;
1014 		}
1015 		if (vtoc->efi_parts[i].p_tag == V_RESERVED) {
1016 			if (resv_part != -1) {
1017 				if (efi_debug) {
1018 					(void) fprintf(stderr, "found "
1019 					    "duplicate reserved partition "
1020 					    "at %d\n", i);
1021 				}
1022 				return (VT_EINVAL);
1023 			}
1024 			resv_part = i;
1025 		}
1026 		if ((vtoc->efi_parts[i].p_start < vtoc->efi_first_u_lba) ||
1027 		    (vtoc->efi_parts[i].p_start > vtoc->efi_last_u_lba)) {
1028 			if (efi_debug) {
1029 				(void) fprintf(stderr,
1030 				    "Partition %d starts at %llu.  ",
1031 				    i,
1032 				    vtoc->efi_parts[i].p_start);
1033 				(void) fprintf(stderr,
1034 				    "It must be between %llu and %llu.\n",
1035 				    vtoc->efi_first_u_lba,
1036 				    vtoc->efi_last_u_lba);
1037 			}
1038 			return (VT_EINVAL);
1039 		}
1040 		if ((vtoc->efi_parts[i].p_start +
1041 		    vtoc->efi_parts[i].p_size <
1042 		    vtoc->efi_first_u_lba) ||
1043 		    (vtoc->efi_parts[i].p_start +
1044 		    vtoc->efi_parts[i].p_size >
1045 		    vtoc->efi_last_u_lba + 1)) {
1046 			if (efi_debug) {
1047 				(void) fprintf(stderr,
1048 				    "Partition %d ends at %llu.  ",
1049 				    i,
1050 				    vtoc->efi_parts[i].p_start +
1051 				    vtoc->efi_parts[i].p_size);
1052 				(void) fprintf(stderr,
1053 				    "It must be between %llu and %llu.\n",
1054 				    vtoc->efi_first_u_lba,
1055 				    vtoc->efi_last_u_lba);
1056 			}
1057 			return (VT_EINVAL);
1058 		}
1059 
1060 		for (j = 0; j < vtoc->efi_nparts; j++) {
1061 			isize = vtoc->efi_parts[i].p_size;
1062 			jsize = vtoc->efi_parts[j].p_size;
1063 			istart = vtoc->efi_parts[i].p_start;
1064 			jstart = vtoc->efi_parts[j].p_start;
1065 			if ((i != j) && (isize != 0) && (jsize != 0)) {
1066 				endsect = jstart + jsize -1;
1067 				if ((jstart <= istart) &&
1068 				    (istart <= endsect)) {
1069 					if (efi_debug) {
1070 						(void) fprintf(stderr,
1071 						    "Partition %d overlaps "
1072 						    "partition %d.", i, j);
1073 					}
1074 					return (VT_EINVAL);
1075 				}
1076 			}
1077 		}
1078 	}
1079 	/* just a warning for now */
1080 	if ((resv_part == -1) && efi_debug) {
1081 		(void) fprintf(stderr,
1082 		    "no reserved partition found\n");
1083 	}
1084 	return (0);
1085 }
1086 
1087 static int
1088 call_blkpg_ioctl(int fd, int command, diskaddr_t start,
1089     diskaddr_t size, uint_t pno)
1090 {
1091 	struct blkpg_ioctl_arg ioctl_arg;
1092 	struct blkpg_partition  linux_part;
1093 	memset(&linux_part, 0, sizeof (linux_part));
1094 
1095 	char *path = efi_get_devname(fd);
1096 	if (path == NULL) {
1097 		(void) fprintf(stderr, "failed to retrieve device name\n");
1098 		return (VT_EINVAL);
1099 	}
1100 
1101 	linux_part.start = start;
1102 	linux_part.length = size;
1103 	linux_part.pno = pno;
1104 	snprintf(linux_part.devname, BLKPG_DEVNAMELTH - 1, "%s%u", path, pno);
1105 	linux_part.devname[BLKPG_DEVNAMELTH - 1] = '\0';
1106 	free(path);
1107 
1108 	ioctl_arg.op = command;
1109 	ioctl_arg.flags = 0;
1110 	ioctl_arg.datalen = sizeof (struct blkpg_partition);
1111 	ioctl_arg.data = &linux_part;
1112 
1113 	return (ioctl(fd, BLKPG, &ioctl_arg));
1114 }
1115 
1116 /*
1117  * add all the unallocated space to the current label
1118  */
1119 int
1120 efi_use_whole_disk(int fd)
1121 {
1122 	struct dk_gpt *efi_label = NULL;
1123 	int rval;
1124 	int i;
1125 	uint_t resv_index = 0, data_index = 0;
1126 	diskaddr_t resv_start = 0, data_start = 0;
1127 	diskaddr_t data_size, limit, difference;
1128 	boolean_t sync_needed = B_FALSE;
1129 	uint_t nblocks;
1130 
1131 	rval = efi_alloc_and_read(fd, &efi_label);
1132 	if (rval < 0) {
1133 		if (efi_label != NULL)
1134 			efi_free(efi_label);
1135 		return (rval);
1136 	}
1137 
1138 	/*
1139 	 * Find the last physically non-zero partition.
1140 	 * This should be the reserved partition.
1141 	 */
1142 	for (i = 0; i < efi_label->efi_nparts; i ++) {
1143 		if (resv_start < efi_label->efi_parts[i].p_start) {
1144 			resv_start = efi_label->efi_parts[i].p_start;
1145 			resv_index = i;
1146 		}
1147 	}
1148 
1149 	/*
1150 	 * Find the last physically non-zero partition before that.
1151 	 * This is the data partition.
1152 	 */
1153 	for (i = 0; i < resv_index; i ++) {
1154 		if (data_start < efi_label->efi_parts[i].p_start) {
1155 			data_start = efi_label->efi_parts[i].p_start;
1156 			data_index = i;
1157 		}
1158 	}
1159 	data_size = efi_label->efi_parts[data_index].p_size;
1160 
1161 	/*
1162 	 * See the "efi_alloc_and_init" function for more information
1163 	 * about where this "nblocks" value comes from.
1164 	 */
1165 	nblocks = efi_label->efi_first_u_lba - 1;
1166 
1167 	/*
1168 	 * Determine if the EFI label is out of sync. We check that:
1169 	 *
1170 	 * 1. the data partition ends at the limit we set, and
1171 	 * 2. the reserved partition starts at the limit we set.
1172 	 *
1173 	 * If either of these conditions is not met, then we need to
1174 	 * resync the EFI label.
1175 	 *
1176 	 * The limit is the last usable LBA, determined by the last LBA
1177 	 * and the first usable LBA fields on the EFI label of the disk
1178 	 * (see the lines directly above). Additionally, we factor in
1179 	 * EFI_MIN_RESV_SIZE (per its use in "zpool_label_disk") and
1180 	 * P2ALIGN it to ensure the partition boundaries are aligned
1181 	 * (for performance reasons). The alignment should match the
1182 	 * alignment used by the "zpool_label_disk" function.
1183 	 */
1184 	limit = P2ALIGN(efi_label->efi_last_lba - nblocks - EFI_MIN_RESV_SIZE,
1185 	    PARTITION_END_ALIGNMENT);
1186 	if (data_start + data_size != limit || resv_start != limit)
1187 		sync_needed = B_TRUE;
1188 
1189 	if (efi_debug && sync_needed)
1190 		(void) fprintf(stderr, "efi_use_whole_disk: sync needed\n");
1191 
1192 	/*
1193 	 * If alter_lba is 1, we are using the backup label.
1194 	 * Since we can locate the backup label by disk capacity,
1195 	 * there must be no unallocated space.
1196 	 */
1197 	if ((efi_label->efi_altern_lba == 1) || (efi_label->efi_altern_lba
1198 	    >= efi_label->efi_last_lba && !sync_needed)) {
1199 		if (efi_debug) {
1200 			(void) fprintf(stderr,
1201 			    "efi_use_whole_disk: requested space not found\n");
1202 		}
1203 		efi_free(efi_label);
1204 		return (VT_ENOSPC);
1205 	}
1206 
1207 	/*
1208 	 * Verify that we've found the reserved partition by checking
1209 	 * that it looks the way it did when we created it in zpool_label_disk.
1210 	 * If we've found the incorrect partition, then we know that this
1211 	 * device was reformatted and no longer is solely used by ZFS.
1212 	 */
1213 	if ((efi_label->efi_parts[resv_index].p_size != EFI_MIN_RESV_SIZE) ||
1214 	    (efi_label->efi_parts[resv_index].p_tag != V_RESERVED) ||
1215 	    (resv_index != 8)) {
1216 		if (efi_debug) {
1217 			(void) fprintf(stderr,
1218 			    "efi_use_whole_disk: wholedisk not available\n");
1219 		}
1220 		efi_free(efi_label);
1221 		return (VT_ENOSPC);
1222 	}
1223 
1224 	if (data_start + data_size != resv_start) {
1225 		if (efi_debug) {
1226 			(void) fprintf(stderr,
1227 			    "efi_use_whole_disk: "
1228 			    "data_start (%lli) + "
1229 			    "data_size (%lli) != "
1230 			    "resv_start (%lli)\n",
1231 			    data_start, data_size, resv_start);
1232 		}
1233 
1234 		return (VT_EINVAL);
1235 	}
1236 
1237 	if (limit < resv_start) {
1238 		if (efi_debug) {
1239 			(void) fprintf(stderr,
1240 			    "efi_use_whole_disk: "
1241 			    "limit (%lli) < resv_start (%lli)\n",
1242 			    limit, resv_start);
1243 		}
1244 
1245 		return (VT_EINVAL);
1246 	}
1247 
1248 	difference = limit - resv_start;
1249 
1250 	if (efi_debug)
1251 		(void) fprintf(stderr,
1252 		    "efi_use_whole_disk: difference is %lli\n", difference);
1253 
1254 	/*
1255 	 * Move the reserved partition. There is currently no data in
1256 	 * here except fabricated devids (which get generated via
1257 	 * efi_write()). So there is no need to copy data.
1258 	 */
1259 	efi_label->efi_parts[data_index].p_size += difference;
1260 	efi_label->efi_parts[resv_index].p_start += difference;
1261 	efi_label->efi_last_u_lba = efi_label->efi_last_lba - nblocks;
1262 
1263 	/*
1264 	 * Rescanning the partition table in the kernel can result
1265 	 * in the device links to be removed (see comment in vdev_disk_open).
1266 	 * If BLKPG_RESIZE_PARTITION is available, then we can resize
1267 	 * the partition table online and avoid having to remove the device
1268 	 * links used by the pool. This provides a very deterministic
1269 	 * approach to resizing devices and does not require any
1270 	 * loops waiting for devices to reappear.
1271 	 */
1272 #ifdef BLKPG_RESIZE_PARTITION
1273 	/*
1274 	 * Delete the reserved partition since we're about to expand
1275 	 * the data partition and it would overlap with the reserved
1276 	 * partition.
1277 	 * NOTE: The starting index for the ioctl is 1 while for the
1278 	 * EFI partitions it's 0. For that reason we have to add one
1279 	 * whenever we make an ioctl call.
1280 	 */
1281 	rval = call_blkpg_ioctl(fd, BLKPG_DEL_PARTITION, 0, 0, resv_index + 1);
1282 	if (rval != 0)
1283 		goto out;
1284 
1285 	/*
1286 	 * Expand the data partition
1287 	 */
1288 	rval = call_blkpg_ioctl(fd, BLKPG_RESIZE_PARTITION,
1289 	    efi_label->efi_parts[data_index].p_start * efi_label->efi_lbasize,
1290 	    efi_label->efi_parts[data_index].p_size * efi_label->efi_lbasize,
1291 	    data_index + 1);
1292 	if (rval != 0) {
1293 		(void) fprintf(stderr, "Unable to resize data "
1294 		    "partition:  %d\n", rval);
1295 		/*
1296 		 * Since we failed to resize, we need to reset the start
1297 		 * of the reserve partition and re-create it.
1298 		 */
1299 		efi_label->efi_parts[resv_index].p_start -= difference;
1300 	}
1301 
1302 	/*
1303 	 * Re-add the reserved partition. If we've expanded the data partition
1304 	 * then we'll move the reserve partition to the end of the data
1305 	 * partition. Otherwise, we'll recreate the partition in its original
1306 	 * location. Note that we do this as best-effort and ignore any
1307 	 * errors that may arise here. This will ensure that we finish writing
1308 	 * the EFI label.
1309 	 */
1310 	(void) call_blkpg_ioctl(fd, BLKPG_ADD_PARTITION,
1311 	    efi_label->efi_parts[resv_index].p_start * efi_label->efi_lbasize,
1312 	    efi_label->efi_parts[resv_index].p_size * efi_label->efi_lbasize,
1313 	    resv_index + 1);
1314 #endif
1315 
1316 	/*
1317 	 * We're now ready to write the EFI label.
1318 	 */
1319 	if (rval == 0) {
1320 		rval = efi_write(fd, efi_label);
1321 		if (rval < 0 && efi_debug) {
1322 			(void) fprintf(stderr, "efi_use_whole_disk:fail "
1323 			    "to write label, rval=%d\n", rval);
1324 		}
1325 	}
1326 
1327 out:
1328 	efi_free(efi_label);
1329 	return (rval);
1330 }
1331 
1332 /*
1333  * write EFI label and backup label
1334  */
1335 int
1336 efi_write(int fd, struct dk_gpt *vtoc)
1337 {
1338 	dk_efi_t		dk_ioc;
1339 	efi_gpt_t		*efi;
1340 	efi_gpe_t		*efi_parts;
1341 	int			i, j;
1342 	struct dk_cinfo		dki_info;
1343 	int			rval;
1344 	int			md_flag = 0;
1345 	int			nblocks;
1346 	diskaddr_t		lba_backup_gpt_hdr;
1347 
1348 	if ((rval = efi_get_info(fd, &dki_info)) != 0)
1349 		return (rval);
1350 
1351 	/* check if we are dealing with a metadevice */
1352 	if ((strncmp(dki_info.dki_cname, "pseudo", 7) == 0) &&
1353 	    (strncmp(dki_info.dki_dname, "md", 3) == 0)) {
1354 		md_flag = 1;
1355 	}
1356 
1357 	if (check_input(vtoc)) {
1358 		/*
1359 		 * not valid; if it's a metadevice just pass it down
1360 		 * because SVM will do its own checking
1361 		 */
1362 		if (md_flag == 0) {
1363 			return (VT_EINVAL);
1364 		}
1365 	}
1366 
1367 	dk_ioc.dki_lba = 1;
1368 	if (NBLOCKS(vtoc->efi_nparts, vtoc->efi_lbasize) < 34) {
1369 		dk_ioc.dki_length = EFI_MIN_ARRAY_SIZE + vtoc->efi_lbasize;
1370 	} else {
1371 		dk_ioc.dki_length = NBLOCKS(vtoc->efi_nparts,
1372 		    vtoc->efi_lbasize) *
1373 		    vtoc->efi_lbasize;
1374 	}
1375 
1376 	/*
1377 	 * the number of blocks occupied by GUID partition entry array
1378 	 */
1379 	nblocks = dk_ioc.dki_length / vtoc->efi_lbasize - 1;
1380 
1381 	/*
1382 	 * Backup GPT header is located on the block after GUID
1383 	 * partition entry array. Here, we calculate the address
1384 	 * for backup GPT header.
1385 	 */
1386 	lba_backup_gpt_hdr = vtoc->efi_last_u_lba + 1 + nblocks;
1387 	if (posix_memalign((void **)&dk_ioc.dki_data,
1388 	    vtoc->efi_lbasize, dk_ioc.dki_length))
1389 		return (VT_ERROR);
1390 
1391 	memset(dk_ioc.dki_data, 0, dk_ioc.dki_length);
1392 	efi = dk_ioc.dki_data;
1393 
1394 	/* stuff user's input into EFI struct */
1395 	efi->efi_gpt_Signature = LE_64(EFI_SIGNATURE);
1396 	efi->efi_gpt_Revision = LE_32(vtoc->efi_version); /* 0x02000100 */
1397 	efi->efi_gpt_HeaderSize = LE_32(sizeof (struct efi_gpt) - LEN_EFI_PAD);
1398 	efi->efi_gpt_Reserved1 = 0;
1399 	efi->efi_gpt_MyLBA = LE_64(1ULL);
1400 	efi->efi_gpt_AlternateLBA = LE_64(lba_backup_gpt_hdr);
1401 	efi->efi_gpt_FirstUsableLBA = LE_64(vtoc->efi_first_u_lba);
1402 	efi->efi_gpt_LastUsableLBA = LE_64(vtoc->efi_last_u_lba);
1403 	efi->efi_gpt_PartitionEntryLBA = LE_64(2ULL);
1404 	efi->efi_gpt_NumberOfPartitionEntries = LE_32(vtoc->efi_nparts);
1405 	efi->efi_gpt_SizeOfPartitionEntry = LE_32(sizeof (struct efi_gpe));
1406 	UUID_LE_CONVERT(efi->efi_gpt_DiskGUID, vtoc->efi_disk_uguid);
1407 
1408 	/* LINTED -- always longlong aligned */
1409 	efi_parts = (efi_gpe_t *)((char *)dk_ioc.dki_data + vtoc->efi_lbasize);
1410 
1411 	for (i = 0; i < vtoc->efi_nparts; i++) {
1412 		for (j = 0;
1413 		    j < sizeof (conversion_array) /
1414 		    sizeof (struct uuid_to_ptag); j++) {
1415 
1416 			if (vtoc->efi_parts[i].p_tag == j) {
1417 				UUID_LE_CONVERT(
1418 				    efi_parts[i].efi_gpe_PartitionTypeGUID,
1419 				    conversion_array[j].uuid);
1420 				break;
1421 			}
1422 		}
1423 
1424 		if (j == sizeof (conversion_array) /
1425 		    sizeof (struct uuid_to_ptag)) {
1426 			/*
1427 			 * If we didn't have a matching uuid match, bail here.
1428 			 * Don't write a label with unknown uuid.
1429 			 */
1430 			if (efi_debug) {
1431 				(void) fprintf(stderr,
1432 				    "Unknown uuid for p_tag %d\n",
1433 				    vtoc->efi_parts[i].p_tag);
1434 			}
1435 			return (VT_EINVAL);
1436 		}
1437 
1438 		/* Zero's should be written for empty partitions */
1439 		if (vtoc->efi_parts[i].p_tag == V_UNASSIGNED)
1440 			continue;
1441 
1442 		efi_parts[i].efi_gpe_StartingLBA =
1443 		    LE_64(vtoc->efi_parts[i].p_start);
1444 		efi_parts[i].efi_gpe_EndingLBA =
1445 		    LE_64(vtoc->efi_parts[i].p_start +
1446 		    vtoc->efi_parts[i].p_size - 1);
1447 		efi_parts[i].efi_gpe_Attributes.PartitionAttrs =
1448 		    LE_16(vtoc->efi_parts[i].p_flag);
1449 		for (j = 0; j < EFI_PART_NAME_LEN; j++) {
1450 			efi_parts[i].efi_gpe_PartitionName[j] =
1451 			    LE_16((ushort_t)vtoc->efi_parts[i].p_name[j]);
1452 		}
1453 		if ((vtoc->efi_parts[i].p_tag != V_UNASSIGNED) &&
1454 		    uuid_is_null((uchar_t *)&vtoc->efi_parts[i].p_uguid)) {
1455 			(void) uuid_generate((uchar_t *)
1456 			    &vtoc->efi_parts[i].p_uguid);
1457 		}
1458 		bcopy(&vtoc->efi_parts[i].p_uguid,
1459 		    &efi_parts[i].efi_gpe_UniquePartitionGUID,
1460 		    sizeof (uuid_t));
1461 	}
1462 	efi->efi_gpt_PartitionEntryArrayCRC32 =
1463 	    LE_32(efi_crc32((unsigned char *)efi_parts,
1464 	    vtoc->efi_nparts * (int)sizeof (struct efi_gpe)));
1465 	efi->efi_gpt_HeaderCRC32 =
1466 	    LE_32(efi_crc32((unsigned char *)efi,
1467 	    LE_32(efi->efi_gpt_HeaderSize)));
1468 
1469 	if (efi_ioctl(fd, DKIOCSETEFI, &dk_ioc) == -1) {
1470 		free(dk_ioc.dki_data);
1471 		switch (errno) {
1472 		case EIO:
1473 			return (VT_EIO);
1474 		case EINVAL:
1475 			return (VT_EINVAL);
1476 		default:
1477 			return (VT_ERROR);
1478 		}
1479 	}
1480 	/* if it's a metadevice we're done */
1481 	if (md_flag) {
1482 		free(dk_ioc.dki_data);
1483 		return (0);
1484 	}
1485 
1486 	/* write backup partition array */
1487 	dk_ioc.dki_lba = vtoc->efi_last_u_lba + 1;
1488 	dk_ioc.dki_length -= vtoc->efi_lbasize;
1489 	/* LINTED */
1490 	dk_ioc.dki_data = (efi_gpt_t *)((char *)dk_ioc.dki_data +
1491 	    vtoc->efi_lbasize);
1492 
1493 	if (efi_ioctl(fd, DKIOCSETEFI, &dk_ioc) == -1) {
1494 		/*
1495 		 * we wrote the primary label okay, so don't fail
1496 		 */
1497 		if (efi_debug) {
1498 			(void) fprintf(stderr,
1499 			    "write of backup partitions to block %llu "
1500 			    "failed, errno %d\n",
1501 			    vtoc->efi_last_u_lba + 1,
1502 			    errno);
1503 		}
1504 	}
1505 	/*
1506 	 * now swap MyLBA and AlternateLBA fields and write backup
1507 	 * partition table header
1508 	 */
1509 	dk_ioc.dki_lba = lba_backup_gpt_hdr;
1510 	dk_ioc.dki_length = vtoc->efi_lbasize;
1511 	/* LINTED */
1512 	dk_ioc.dki_data = (efi_gpt_t *)((char *)dk_ioc.dki_data -
1513 	    vtoc->efi_lbasize);
1514 	efi->efi_gpt_AlternateLBA = LE_64(1ULL);
1515 	efi->efi_gpt_MyLBA = LE_64(lba_backup_gpt_hdr);
1516 	efi->efi_gpt_PartitionEntryLBA = LE_64(vtoc->efi_last_u_lba + 1);
1517 	efi->efi_gpt_HeaderCRC32 = 0;
1518 	efi->efi_gpt_HeaderCRC32 =
1519 	    LE_32(efi_crc32((unsigned char *)dk_ioc.dki_data,
1520 	    LE_32(efi->efi_gpt_HeaderSize)));
1521 
1522 	if (efi_ioctl(fd, DKIOCSETEFI, &dk_ioc) == -1) {
1523 		if (efi_debug) {
1524 			(void) fprintf(stderr,
1525 			    "write of backup header to block %llu failed, "
1526 			    "errno %d\n",
1527 			    lba_backup_gpt_hdr,
1528 			    errno);
1529 		}
1530 	}
1531 	/* write the PMBR */
1532 	(void) write_pmbr(fd, vtoc);
1533 	free(dk_ioc.dki_data);
1534 
1535 	return (0);
1536 }
1537 
1538 void
1539 efi_free(struct dk_gpt *ptr)
1540 {
1541 	free(ptr);
1542 }
1543 
1544 /*
1545  * Input: File descriptor
1546  * Output: 1 if disk has an EFI label, or > 2TB with no VTOC or legacy MBR.
1547  * Otherwise 0.
1548  */
1549 int
1550 efi_type(int fd)
1551 {
1552 #if 0
1553 	struct vtoc vtoc;
1554 	struct extvtoc extvtoc;
1555 
1556 	if (ioctl(fd, DKIOCGEXTVTOC, &extvtoc) == -1) {
1557 		if (errno == ENOTSUP)
1558 			return (1);
1559 		else if (errno == ENOTTY) {
1560 			if (ioctl(fd, DKIOCGVTOC, &vtoc) == -1)
1561 				if (errno == ENOTSUP)
1562 					return (1);
1563 		}
1564 	}
1565 	return (0);
1566 #else
1567 	return (ENOSYS);
1568 #endif
1569 }
1570 
1571 void
1572 efi_err_check(struct dk_gpt *vtoc)
1573 {
1574 	int			resv_part = -1;
1575 	int			i, j;
1576 	diskaddr_t		istart, jstart, isize, jsize, endsect;
1577 	int			overlap = 0;
1578 
1579 	/*
1580 	 * make sure no partitions overlap
1581 	 */
1582 	for (i = 0; i < vtoc->efi_nparts; i++) {
1583 		/* It can't be unassigned and have an actual size */
1584 		if ((vtoc->efi_parts[i].p_tag == V_UNASSIGNED) &&
1585 		    (vtoc->efi_parts[i].p_size != 0)) {
1586 			(void) fprintf(stderr,
1587 			    "partition %d is \"unassigned\" but has a size "
1588 			    "of %llu\n", i, vtoc->efi_parts[i].p_size);
1589 		}
1590 		if (vtoc->efi_parts[i].p_tag == V_UNASSIGNED) {
1591 			continue;
1592 		}
1593 		if (vtoc->efi_parts[i].p_tag == V_RESERVED) {
1594 			if (resv_part != -1) {
1595 				(void) fprintf(stderr,
1596 				    "found duplicate reserved partition at "
1597 				    "%d\n", i);
1598 			}
1599 			resv_part = i;
1600 			if (vtoc->efi_parts[i].p_size != EFI_MIN_RESV_SIZE)
1601 				(void) fprintf(stderr,
1602 				    "Warning: reserved partition size must "
1603 				    "be %d sectors\n", EFI_MIN_RESV_SIZE);
1604 		}
1605 		if ((vtoc->efi_parts[i].p_start < vtoc->efi_first_u_lba) ||
1606 		    (vtoc->efi_parts[i].p_start > vtoc->efi_last_u_lba)) {
1607 			(void) fprintf(stderr,
1608 			    "Partition %d starts at %llu\n",
1609 			    i,
1610 			    vtoc->efi_parts[i].p_start);
1611 			(void) fprintf(stderr,
1612 			    "It must be between %llu and %llu.\n",
1613 			    vtoc->efi_first_u_lba,
1614 			    vtoc->efi_last_u_lba);
1615 		}
1616 		if ((vtoc->efi_parts[i].p_start +
1617 		    vtoc->efi_parts[i].p_size <
1618 		    vtoc->efi_first_u_lba) ||
1619 		    (vtoc->efi_parts[i].p_start +
1620 		    vtoc->efi_parts[i].p_size >
1621 		    vtoc->efi_last_u_lba + 1)) {
1622 			(void) fprintf(stderr,
1623 			    "Partition %d ends at %llu\n",
1624 			    i,
1625 			    vtoc->efi_parts[i].p_start +
1626 			    vtoc->efi_parts[i].p_size);
1627 			(void) fprintf(stderr,
1628 			    "It must be between %llu and %llu.\n",
1629 			    vtoc->efi_first_u_lba,
1630 			    vtoc->efi_last_u_lba);
1631 		}
1632 
1633 		for (j = 0; j < vtoc->efi_nparts; j++) {
1634 			isize = vtoc->efi_parts[i].p_size;
1635 			jsize = vtoc->efi_parts[j].p_size;
1636 			istart = vtoc->efi_parts[i].p_start;
1637 			jstart = vtoc->efi_parts[j].p_start;
1638 			if ((i != j) && (isize != 0) && (jsize != 0)) {
1639 				endsect = jstart + jsize -1;
1640 				if ((jstart <= istart) &&
1641 				    (istart <= endsect)) {
1642 					if (!overlap) {
1643 					(void) fprintf(stderr,
1644 					    "label error: EFI Labels do not "
1645 					    "support overlapping partitions\n");
1646 					}
1647 					(void) fprintf(stderr,
1648 					    "Partition %d overlaps partition "
1649 					    "%d.\n", i, j);
1650 					overlap = 1;
1651 				}
1652 			}
1653 		}
1654 	}
1655 	/* make sure there is a reserved partition */
1656 	if (resv_part == -1) {
1657 		(void) fprintf(stderr,
1658 		    "no reserved partition found\n");
1659 	}
1660 }
1661