xref: /openbmc/u-boot/cmd/gpt.c (revision 407b5b956a2e0facf6668fc8b295f4be9205c83e)
1  // SPDX-License-Identifier: GPL-2.0+
2  /*
3   * cmd_gpt.c -- GPT (GUID Partition Table) handling command
4   *
5   * Copyright (C) 2015
6   * Lukasz Majewski <l.majewski@majess.pl>
7   *
8   * Copyright (C) 2012 Samsung Electronics
9   * author: Lukasz Majewski <l.majewski@samsung.com>
10   * author: Piotr Wilczek <p.wilczek@samsung.com>
11   */
12  
13  #include <common.h>
14  #include <malloc.h>
15  #include <command.h>
16  #include <part_efi.h>
17  #include <exports.h>
18  #include <linux/ctype.h>
19  #include <div64.h>
20  #include <memalign.h>
21  #include <linux/compat.h>
22  #include <linux/sizes.h>
23  #include <stdlib.h>
24  
25  static LIST_HEAD(disk_partitions);
26  
27  /**
28   * extract_env(): Expand env name from string format '&{env_name}'
29   *                and return pointer to the env (if the env is set)
30   *
31   * @param str - pointer to string
32   * @param env - pointer to pointer to extracted env
33   *
34   * @return - zero on successful expand and env is set
35   */
36  static int extract_env(const char *str, char **env)
37  {
38  	int ret = -1;
39  	char *e, *s;
40  #ifdef CONFIG_RANDOM_UUID
41  	char uuid_str[UUID_STR_LEN + 1];
42  #endif
43  
44  	if (!str || strlen(str) < 4)
45  		return -1;
46  
47  	if (!((strncmp(str, "${", 2) == 0) && (str[strlen(str) - 1] == '}')))
48  		return -1;
49  
50  	s = strdup(str);
51  	if (s == NULL)
52  		return -1;
53  
54  	memset(s + strlen(s) - 1, '\0', 1);
55  	memmove(s, s + 2, strlen(s) - 1);
56  
57  	e = env_get(s);
58  	if (e == NULL) {
59  #ifdef CONFIG_RANDOM_UUID
60  		debug("%s unset. ", str);
61  		gen_rand_uuid_str(uuid_str, UUID_STR_FORMAT_GUID);
62  		env_set(s, uuid_str);
63  
64  		e = env_get(s);
65  		if (e) {
66  			debug("Set to random.\n");
67  			ret = 0;
68  		} else {
69  			debug("Can't get random UUID.\n");
70  		}
71  #else
72  		debug("%s unset.\n", str);
73  #endif
74  	} else {
75  		debug("%s get from environment.\n", str);
76  		ret = 0;
77  	}
78  
79  	*env = e;
80  	free(s);
81  
82  	return ret;
83  }
84  
85  /**
86   * extract_val(): Extract value from a key=value pair list (comma separated).
87   *                Only value for the given key is returend.
88   *                Function allocates memory for the value, remember to free!
89   *
90   * @param str - pointer to string with key=values pairs
91   * @param key - pointer to the key to search for
92   *
93   * @return - pointer to allocated string with the value
94   */
95  static char *extract_val(const char *str, const char *key)
96  {
97  	char *v, *k;
98  	char *s, *strcopy;
99  	char *new = NULL;
100  
101  	strcopy = strdup(str);
102  	if (strcopy == NULL)
103  		return NULL;
104  
105  	s = strcopy;
106  	while (s) {
107  		v = strsep(&s, ",");
108  		if (!v)
109  			break;
110  		k = strsep(&v, "=");
111  		if (!k)
112  			break;
113  		if  (strcmp(k, key) == 0) {
114  			new = strdup(v);
115  			break;
116  		}
117  	}
118  
119  	free(strcopy);
120  
121  	return new;
122  }
123  
124  /**
125   * found_key(): Found key without value in parameter list (comma separated).
126   *
127   * @param str - pointer to string with key
128   * @param key - pointer to the key to search for
129   *
130   * @return - true on found key
131   */
132  static bool found_key(const char *str, const char *key)
133  {
134  	char *k;
135  	char *s, *strcopy;
136  	bool result = false;
137  
138  	strcopy = strdup(str);
139  	if (!strcopy)
140  		return NULL;
141  
142  	s = strcopy;
143  	while (s) {
144  		k = strsep(&s, ",");
145  		if (!k)
146  			break;
147  		if  (strcmp(k, key) == 0) {
148  			result = true;
149  			break;
150  		}
151  	}
152  
153  	free(strcopy);
154  
155  	return result;
156  }
157  
158  static int calc_parts_list_len(int numparts)
159  {
160  	int partlistlen = UUID_STR_LEN + 1 + strlen("uuid_disk=");
161  	/* for the comma */
162  	partlistlen++;
163  
164  	/* per-partition additions; numparts starts at 1, so this should be correct */
165  	partlistlen += numparts * (strlen("name=,") + PART_NAME_LEN + 1);
166  	/* see part.h for definition of struct disk_partition */
167  	partlistlen += numparts * (strlen("start=MiB,") + sizeof(lbaint_t) + 1);
168  	partlistlen += numparts * (strlen("size=MiB,") + sizeof(lbaint_t) + 1);
169  	partlistlen += numparts * (strlen("uuid=;") + UUID_STR_LEN + 1);
170  	/* for the terminating null */
171  	partlistlen++;
172  	debug("Length of partitions_list is %d for %d partitions\n", partlistlen,
173  	      numparts);
174  	return partlistlen;
175  }
176  
177  #ifdef CONFIG_CMD_GPT_RENAME
178  static void del_gpt_info(void)
179  {
180  	struct list_head *pos = &disk_partitions;
181  	struct disk_part *curr;
182  	while (!list_empty(pos)) {
183  		curr = list_entry(pos->next, struct disk_part, list);
184  		list_del(pos->next);
185  		free(curr);
186  	}
187  }
188  
189  static struct disk_part *allocate_disk_part(disk_partition_t *info, int partnum)
190  {
191  	struct disk_part *newpart;
192  	newpart = calloc(1, sizeof(struct disk_part));
193  	if (!newpart)
194  		return ERR_PTR(-ENOMEM);
195  
196  	newpart->gpt_part_info.start = info->start;
197  	newpart->gpt_part_info.size = info->size;
198  	newpart->gpt_part_info.blksz = info->blksz;
199  	strncpy((char *)newpart->gpt_part_info.name, (const char *)info->name,
200  		PART_NAME_LEN);
201  	newpart->gpt_part_info.name[PART_NAME_LEN - 1] = '\0';
202  	strncpy((char *)newpart->gpt_part_info.type, (const char *)info->type,
203  		PART_TYPE_LEN);
204  	newpart->gpt_part_info.type[PART_TYPE_LEN - 1] = '\0';
205  	newpart->gpt_part_info.bootable = info->bootable;
206  #ifdef CONFIG_PARTITION_UUIDS
207  	strncpy(newpart->gpt_part_info.uuid, (const char *)info->uuid,
208  		UUID_STR_LEN);
209  	/* UUID_STR_LEN is correct, as uuid[]'s length is UUID_STR_LEN+1 chars */
210  	newpart->gpt_part_info.uuid[UUID_STR_LEN] = '\0';
211  #endif
212  	newpart->partnum = partnum;
213  
214  	return newpart;
215  }
216  
217  static void prettyprint_part_size(char *sizestr, lbaint_t partsize,
218  				  lbaint_t blksize)
219  {
220  	unsigned long long partbytes, partmegabytes;
221  
222  	partbytes = partsize * blksize;
223  	partmegabytes = lldiv(partbytes, SZ_1M);
224  	snprintf(sizestr, 16, "%lluMiB", partmegabytes);
225  }
226  
227  static void print_gpt_info(void)
228  {
229  	struct list_head *pos;
230  	struct disk_part *curr;
231  	char partstartstr[16];
232  	char partsizestr[16];
233  
234  	list_for_each(pos, &disk_partitions) {
235  		curr = list_entry(pos, struct disk_part, list);
236  		prettyprint_part_size(partstartstr, curr->gpt_part_info.start,
237  				      curr->gpt_part_info.blksz);
238  		prettyprint_part_size(partsizestr, curr->gpt_part_info.size,
239  				      curr->gpt_part_info.blksz);
240  
241  		printf("Partition %d:\n", curr->partnum);
242  		printf("Start %s, size %s\n", partstartstr, partsizestr);
243  		printf("Block size %lu, name %s\n", curr->gpt_part_info.blksz,
244  		       curr->gpt_part_info.name);
245  		printf("Type %s, bootable %d\n", curr->gpt_part_info.type,
246  		       curr->gpt_part_info.bootable);
247  #ifdef CONFIG_PARTITION_UUIDS
248  		printf("UUID %s\n", curr->gpt_part_info.uuid);
249  #endif
250  		printf("\n");
251  	}
252  }
253  
254  /*
255   * create the string that upstream 'gpt write' command will accept as an
256   * argument
257   *
258   * From doc/README.gpt, Format of partitions layout:
259   *    "uuid_disk=...;name=u-boot,size=60MiB,uuid=...;
260   *	name=kernel,size=60MiB,uuid=...;"
261   * The fields 'name' and 'size' are mandatory for every partition.
262   * The field 'start' is optional. The fields 'uuid' and 'uuid_disk'
263   * are optional if CONFIG_RANDOM_UUID is enabled.
264   */
265  static int create_gpt_partitions_list(int numparts, const char *guid,
266  				      char *partitions_list)
267  {
268  	struct list_head *pos;
269  	struct disk_part *curr;
270  	char partstr[PART_NAME_LEN + 1];
271  
272  	if (!partitions_list)
273  		return -EINVAL;
274  
275  	strcpy(partitions_list, "uuid_disk=");
276  	strncat(partitions_list, guid, UUID_STR_LEN + 1);
277  	strcat(partitions_list, ";");
278  
279  	list_for_each(pos, &disk_partitions) {
280  		curr = list_entry(pos, struct disk_part, list);
281  		strcat(partitions_list, "name=");
282  		strncat(partitions_list, (const char *)curr->gpt_part_info.name,
283  			PART_NAME_LEN + 1);
284  		sprintf(partstr, ",start=0x%llx",
285  			(unsigned long long)curr->gpt_part_info.start *
286  					    curr->gpt_part_info.blksz);
287  		/* one extra byte for NULL */
288  		strncat(partitions_list, partstr, PART_NAME_LEN + 1);
289  		sprintf(partstr, ",size=0x%llx",
290  			(unsigned long long)curr->gpt_part_info.size *
291  					    curr->gpt_part_info.blksz);
292  		strncat(partitions_list, partstr, PART_NAME_LEN + 1);
293  
294  		strcat(partitions_list, ",uuid=");
295  		strncat(partitions_list, curr->gpt_part_info.uuid,
296  			UUID_STR_LEN + 1);
297  		strcat(partitions_list, ";");
298  	}
299  	return 0;
300  }
301  
302  /*
303   * read partition info into disk_partitions list where
304   * it can be printed or modified
305   */
306  static int get_gpt_info(struct blk_desc *dev_desc)
307  {
308  	/* start partition numbering at 1, as U-Boot does */
309  	int valid_parts = 0, p, ret;
310  	disk_partition_t info;
311  	struct disk_part *new_disk_part;
312  
313  	/*
314  	 * Always re-read partition info from device, in case
315  	 * it has changed
316  	 */
317  	INIT_LIST_HEAD(&disk_partitions);
318  
319  	for (p = 1; p <= MAX_SEARCH_PARTITIONS; p++) {
320  		ret = part_get_info(dev_desc, p, &info);
321  		if (ret)
322  			continue;
323  
324  		/* Add 1 here because counter is zero-based but p1 is
325  		   the first partition */
326  		new_disk_part = allocate_disk_part(&info, valid_parts+1);
327  		if (IS_ERR(new_disk_part))
328  			goto out;
329  
330  		list_add_tail(&new_disk_part->list, &disk_partitions);
331  		valid_parts++;
332  	}
333  	if (valid_parts == 0) {
334  		printf("** No valid partitions found **\n");
335  		goto out;
336  	}
337  	return valid_parts;
338   out:
339  	if (valid_parts >= 1)
340  		del_gpt_info();
341  	return -ENODEV;
342  }
343  
344  /* a wrapper to test get_gpt_info */
345  static int do_get_gpt_info(struct blk_desc *dev_desc)
346  {
347  	int ret;
348  
349  	ret = get_gpt_info(dev_desc);
350  	if (ret > 0) {
351  		print_gpt_info();
352  		del_gpt_info();
353  		return 0;
354  	}
355  	return ret;
356  }
357  #endif
358  
359  /**
360   * set_gpt_info(): Fill partition information from string
361   *		function allocates memory, remember to free!
362   *
363   * @param dev_desc - pointer block device descriptor
364   * @param str_part - pointer to string with partition information
365   * @param str_disk_guid - pointer to pointer to allocated string with disk guid
366   * @param partitions - pointer to pointer to allocated partitions array
367   * @param parts_count - number of partitions
368   *
369   * @return - zero on success, otherwise error
370   *
371   */
372  static int set_gpt_info(struct blk_desc *dev_desc,
373  			const char *str_part,
374  			char **str_disk_guid,
375  			disk_partition_t **partitions,
376  			u8 *parts_count)
377  {
378  	char *tok, *str, *s;
379  	int i;
380  	char *val, *p;
381  	int p_count;
382  	disk_partition_t *parts;
383  	int errno = 0;
384  	uint64_t size_ll, start_ll;
385  	lbaint_t offset = 0;
386  	int max_str_part = calc_parts_list_len(MAX_SEARCH_PARTITIONS);
387  
388  	debug("%s:  lba num: 0x%x %d\n", __func__,
389  	      (unsigned int)dev_desc->lba, (unsigned int)dev_desc->lba);
390  
391  	if (str_part == NULL)
392  		return -1;
393  
394  	str = strdup(str_part);
395  	if (str == NULL)
396  		return -ENOMEM;
397  
398  	/* extract disk guid */
399  	s = str;
400  	val = extract_val(str, "uuid_disk");
401  	if (!val) {
402  #ifdef CONFIG_RANDOM_UUID
403  		*str_disk_guid = malloc(UUID_STR_LEN + 1);
404  		if (*str_disk_guid == NULL)
405  			return -ENOMEM;
406  		gen_rand_uuid_str(*str_disk_guid, UUID_STR_FORMAT_STD);
407  #else
408  		free(str);
409  		return -2;
410  #endif
411  	} else {
412  		val = strsep(&val, ";");
413  		if (extract_env(val, &p))
414  			p = val;
415  		*str_disk_guid = strdup(p);
416  		free(val);
417  		/* Move s to first partition */
418  		strsep(&s, ";");
419  	}
420  	if (s == NULL) {
421  		printf("Error: is the partitions string NULL-terminated?\n");
422  		return -EINVAL;
423  	}
424  	if (strnlen(s, max_str_part) == 0)
425  		return -3;
426  
427  	i = strnlen(s, max_str_part) - 1;
428  	if (s[i] == ';')
429  		s[i] = '\0';
430  
431  	/* calculate expected number of partitions */
432  	p_count = 1;
433  	p = s;
434  	while (*p) {
435  		if (*p++ == ';')
436  			p_count++;
437  	}
438  
439  	/* allocate memory for partitions */
440  	parts = calloc(sizeof(disk_partition_t), p_count);
441  	if (parts == NULL)
442  		return -ENOMEM;
443  
444  	/* retrieve partitions data from string */
445  	for (i = 0; i < p_count; i++) {
446  		tok = strsep(&s, ";");
447  
448  		if (tok == NULL)
449  			break;
450  
451  		/* uuid */
452  		val = extract_val(tok, "uuid");
453  		if (!val) {
454  			/* 'uuid' is optional if random uuid's are enabled */
455  #ifdef CONFIG_RANDOM_UUID
456  			gen_rand_uuid_str(parts[i].uuid, UUID_STR_FORMAT_STD);
457  #else
458  			errno = -4;
459  			goto err;
460  #endif
461  		} else {
462  			if (extract_env(val, &p))
463  				p = val;
464  			if (strnlen(p, max_str_part) >= sizeof(parts[i].uuid)) {
465  				printf("Wrong uuid format for partition %d\n", i);
466  				errno = -4;
467  				goto err;
468  			}
469  			strncpy((char *)parts[i].uuid, p, max_str_part);
470  			free(val);
471  		}
472  #ifdef CONFIG_PARTITION_TYPE_GUID
473  		/* guid */
474  		val = extract_val(tok, "type");
475  		if (val) {
476  			/* 'type' is optional */
477  			if (extract_env(val, &p))
478  				p = val;
479  			if (strnlen(p, max_str_part) >= sizeof(parts[i].type_guid)) {
480  				printf("Wrong type guid format for partition %d\n",
481  				       i);
482  				errno = -4;
483  				goto err;
484  			}
485  			strncpy((char *)parts[i].type_guid, p, max_str_part);
486  			free(val);
487  		}
488  #endif
489  		/* name */
490  		val = extract_val(tok, "name");
491  		if (!val) { /* name is mandatory */
492  			errno = -4;
493  			goto err;
494  		}
495  		if (extract_env(val, &p))
496  			p = val;
497  		if (strnlen(p, max_str_part) >= sizeof(parts[i].name)) {
498  			errno = -4;
499  			goto err;
500  		}
501  		strncpy((char *)parts[i].name, p, max_str_part);
502  		free(val);
503  
504  		/* size */
505  		val = extract_val(tok, "size");
506  		if (!val) { /* 'size' is mandatory */
507  			errno = -4;
508  			goto err;
509  		}
510  		if (extract_env(val, &p))
511  			p = val;
512  		if ((strcmp(p, "-") == 0)) {
513  			/* Let part efi module to auto extend the size */
514  			parts[i].size = 0;
515  		} else {
516  			size_ll = ustrtoull(p, &p, 0);
517  			parts[i].size = lldiv(size_ll, dev_desc->blksz);
518  		}
519  
520  		free(val);
521  
522  		/* start address */
523  		val = extract_val(tok, "start");
524  		if (val) { /* start address is optional */
525  			if (extract_env(val, &p))
526  				p = val;
527  			start_ll = ustrtoull(p, &p, 0);
528  			parts[i].start = lldiv(start_ll, dev_desc->blksz);
529  			free(val);
530  		}
531  
532  		offset += parts[i].size + parts[i].start;
533  
534  		/* bootable */
535  		if (found_key(tok, "bootable"))
536  			parts[i].bootable = 1;
537  	}
538  
539  	*parts_count = p_count;
540  	*partitions = parts;
541  	free(str);
542  
543  	return 0;
544  err:
545  	free(str);
546  	free(*str_disk_guid);
547  	free(parts);
548  
549  	return errno;
550  }
551  
552  static int gpt_default(struct blk_desc *blk_dev_desc, const char *str_part)
553  {
554  	int ret;
555  	char *str_disk_guid;
556  	u8 part_count = 0;
557  	disk_partition_t *partitions = NULL;
558  
559  	/* fill partitions */
560  	ret = set_gpt_info(blk_dev_desc, str_part,
561  			&str_disk_guid, &partitions, &part_count);
562  	if (ret) {
563  		if (ret == -1)
564  			printf("No partition list provided\n");
565  		if (ret == -2)
566  			printf("Missing disk guid\n");
567  		if ((ret == -3) || (ret == -4))
568  			printf("Partition list incomplete\n");
569  		return -1;
570  	}
571  
572  	/* save partitions layout to disk */
573  	ret = gpt_restore(blk_dev_desc, str_disk_guid, partitions, part_count);
574  	free(str_disk_guid);
575  	free(partitions);
576  
577  	return ret;
578  }
579  
580  static int gpt_verify(struct blk_desc *blk_dev_desc, const char *str_part)
581  {
582  	ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1,
583  				     blk_dev_desc->blksz);
584  	disk_partition_t *partitions = NULL;
585  	gpt_entry *gpt_pte = NULL;
586  	char *str_disk_guid;
587  	u8 part_count = 0;
588  	int ret = 0;
589  
590  	/* fill partitions */
591  	ret = set_gpt_info(blk_dev_desc, str_part,
592  			&str_disk_guid, &partitions, &part_count);
593  	if (ret) {
594  		if (ret == -1) {
595  			printf("No partition list provided - only basic check\n");
596  			ret = gpt_verify_headers(blk_dev_desc, gpt_head,
597  						 &gpt_pte);
598  			goto out;
599  		}
600  		if (ret == -2)
601  			printf("Missing disk guid\n");
602  		if ((ret == -3) || (ret == -4))
603  			printf("Partition list incomplete\n");
604  		return -1;
605  	}
606  
607  	/* Check partition layout with provided pattern */
608  	ret = gpt_verify_partitions(blk_dev_desc, partitions, part_count,
609  				    gpt_head, &gpt_pte);
610  	free(str_disk_guid);
611  	free(partitions);
612   out:
613  	free(gpt_pte);
614  	return ret;
615  }
616  
617  static int do_disk_guid(struct blk_desc *dev_desc, char * const namestr)
618  {
619  	int ret;
620  	char disk_guid[UUID_STR_LEN + 1];
621  
622  	ret = get_disk_guid(dev_desc, disk_guid);
623  	if (ret < 0)
624  		return CMD_RET_FAILURE;
625  
626  	if (namestr)
627  		env_set(namestr, disk_guid);
628  	else
629  		printf("%s\n", disk_guid);
630  
631  	return ret;
632  }
633  
634  #ifdef CONFIG_CMD_GPT_RENAME
635  /*
636   * There are 3 malloc() calls in set_gpt_info() and there is no info about which
637   * failed.
638   */
639  static void set_gpt_cleanup(char **str_disk_guid,
640  			    disk_partition_t **partitions)
641  {
642  #ifdef CONFIG_RANDOM_UUID
643  	if (str_disk_guid)
644  		free(str_disk_guid);
645  #endif
646  	if (partitions)
647  		free(partitions);
648  }
649  
650  static int do_rename_gpt_parts(struct blk_desc *dev_desc, char *subcomm,
651  			       char *name1, char *name2)
652  {
653  	struct list_head *pos;
654  	struct disk_part *curr;
655  	disk_partition_t *new_partitions = NULL;
656  	char disk_guid[UUID_STR_LEN + 1];
657  	char *partitions_list, *str_disk_guid;
658  	u8 part_count = 0;
659  	int partlistlen, ret, numparts = 0, partnum, i = 1, ctr1 = 0, ctr2 = 0;
660  
661  	if ((subcomm == NULL) || (name1 == NULL) || (name2 == NULL) ||
662  	    (strcmp(subcomm, "swap") && (strcmp(subcomm, "rename"))))
663  		return -EINVAL;
664  
665  	ret = get_disk_guid(dev_desc, disk_guid);
666  	if (ret < 0)
667  		return ret;
668  	/*
669  	 * Allocates disk_partitions, requiring matching call to del_gpt_info()
670  	 * if successful.
671  	 */
672  	numparts = get_gpt_info(dev_desc);
673  	if (numparts <=  0)
674  		return numparts ? numparts : -ENODEV;
675  
676  	partlistlen = calc_parts_list_len(numparts);
677  	partitions_list = malloc(partlistlen);
678  	if (!partitions_list) {
679  		del_gpt_info();
680  		return -ENOMEM;
681  	}
682  	memset(partitions_list, '\0', partlistlen);
683  
684  	ret = create_gpt_partitions_list(numparts, disk_guid, partitions_list);
685  	if (ret < 0) {
686  		free(partitions_list);
687  		return ret;
688  	}
689  	/*
690  	 * Uncomment the following line to print a string that 'gpt write'
691  	 * or 'gpt verify' will accept as input.
692  	 */
693  	debug("OLD partitions_list is %s with %u chars\n", partitions_list,
694  	      (unsigned)strlen(partitions_list));
695  
696  	/* set_gpt_info allocates new_partitions and str_disk_guid */
697  	ret = set_gpt_info(dev_desc, partitions_list, &str_disk_guid,
698  			   &new_partitions, &part_count);
699  	if (ret < 0) {
700  		del_gpt_info();
701  		free(partitions_list);
702  		if (ret == -ENOMEM)
703  			set_gpt_cleanup(&str_disk_guid, &new_partitions);
704  		else
705  			goto out;
706  	}
707  
708  	if (!strcmp(subcomm, "swap")) {
709  		if ((strlen(name1) > PART_NAME_LEN) || (strlen(name2) > PART_NAME_LEN)) {
710  			printf("Names longer than %d characters are truncated.\n", PART_NAME_LEN);
711  			ret = -EINVAL;
712  			goto out;
713  		}
714  		list_for_each(pos, &disk_partitions) {
715  			curr = list_entry(pos, struct disk_part, list);
716  			if (!strcmp((char *)curr->gpt_part_info.name, name1)) {
717  				strcpy((char *)curr->gpt_part_info.name, name2);
718  				ctr1++;
719  			} else if (!strcmp((char *)curr->gpt_part_info.name, name2)) {
720  				strcpy((char *)curr->gpt_part_info.name, name1);
721  				ctr2++;
722  			}
723  		}
724  		if ((ctr1 + ctr2 < 2) || (ctr1 != ctr2)) {
725  			printf("Cannot swap partition names except in pairs.\n");
726  			ret = -EINVAL;
727  			goto out;
728  		}
729  	} else { /* rename */
730  		if (strlen(name2) > PART_NAME_LEN) {
731  			printf("Names longer than %d characters are truncated.\n", PART_NAME_LEN);
732  			ret = -EINVAL;
733  			goto out;
734  		}
735  		partnum = (int)simple_strtol(name1, NULL, 10);
736  		if ((partnum < 0) || (partnum > numparts)) {
737  			printf("Illegal partition number %s\n", name1);
738  			ret = -EINVAL;
739  			goto out;
740  		}
741  		ret = part_get_info(dev_desc, partnum, new_partitions);
742  		if (ret < 0)
743  			goto out;
744  
745  		/* U-Boot partition numbering starts at 1 */
746  		list_for_each(pos, &disk_partitions) {
747  			curr = list_entry(pos, struct disk_part, list);
748  			if (i == partnum) {
749  				strcpy((char *)curr->gpt_part_info.name, name2);
750  				break;
751  			}
752  			i++;
753  		}
754  	}
755  
756  	ret = create_gpt_partitions_list(numparts, disk_guid, partitions_list);
757  	if (ret < 0)
758  		goto out;
759  	debug("NEW partitions_list is %s with %u chars\n", partitions_list,
760  	      (unsigned)strlen(partitions_list));
761  
762  	ret = set_gpt_info(dev_desc, partitions_list, &str_disk_guid,
763  			   &new_partitions, &part_count);
764  	/*
765  	 * Even though valid pointers are here passed into set_gpt_info(),
766  	 * it mallocs again, and there's no way to tell which failed.
767  	 */
768  	if (ret < 0) {
769  		del_gpt_info();
770  		free(partitions_list);
771  		if (ret == -ENOMEM)
772  			set_gpt_cleanup(&str_disk_guid, &new_partitions);
773  		else
774  			goto out;
775  	}
776  
777  	debug("Writing new partition table\n");
778  	ret = gpt_restore(dev_desc, disk_guid, new_partitions, numparts);
779  	if (ret < 0) {
780  		printf("Writing new partition table failed\n");
781  		goto out;
782  	}
783  
784  	debug("Reading back new partition table\n");
785  	/*
786  	 * Empty the existing disk_partitions list, as otherwise the memory in
787  	 * the original list is unreachable.
788  	 */
789  	del_gpt_info();
790  	numparts = get_gpt_info(dev_desc);
791  	if (numparts <=  0) {
792  		ret = numparts ? numparts : -ENODEV;
793  		goto out;
794  	}
795  	printf("new partition table with %d partitions is:\n", numparts);
796  	print_gpt_info();
797  	del_gpt_info();
798   out:
799  	free(new_partitions);
800  	free(str_disk_guid);
801  	free(partitions_list);
802  	return ret;
803  }
804  #endif
805  
806  /**
807   * do_gpt(): Perform GPT operations
808   *
809   * @param cmdtp - command name
810   * @param flag
811   * @param argc
812   * @param argv
813   *
814   * @return zero on success; otherwise error
815   */
816  static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
817  {
818  	int ret = CMD_RET_SUCCESS;
819  	int dev = 0;
820  	char *ep;
821  	struct blk_desc *blk_dev_desc = NULL;
822  
823  #ifndef CONFIG_CMD_GPT_RENAME
824  	if (argc < 4 || argc > 5)
825  #else
826  	if (argc < 4 || argc > 6)
827  #endif
828  		return CMD_RET_USAGE;
829  
830  	dev = (int)simple_strtoul(argv[3], &ep, 10);
831  	if (!ep || ep[0] != '\0') {
832  		printf("'%s' is not a number\n", argv[3]);
833  		return CMD_RET_USAGE;
834  	}
835  	blk_dev_desc = blk_get_dev(argv[2], dev);
836  	if (!blk_dev_desc) {
837  		printf("%s: %s dev %d NOT available\n",
838  		       __func__, argv[2], dev);
839  		return CMD_RET_FAILURE;
840  	}
841  
842  	if ((strcmp(argv[1], "write") == 0) && (argc == 5)) {
843  		printf("Writing GPT: ");
844  		ret = gpt_default(blk_dev_desc, argv[4]);
845  	} else if ((strcmp(argv[1], "verify") == 0)) {
846  		ret = gpt_verify(blk_dev_desc, argv[4]);
847  		printf("Verify GPT: ");
848  	} else if (strcmp(argv[1], "guid") == 0) {
849  		ret = do_disk_guid(blk_dev_desc, argv[4]);
850  #ifdef CONFIG_CMD_GPT_RENAME
851  	} else if (strcmp(argv[1], "read") == 0) {
852  		ret = do_get_gpt_info(blk_dev_desc);
853  	} else if ((strcmp(argv[1], "swap") == 0) ||
854  		   (strcmp(argv[1], "rename") == 0)) {
855  		ret = do_rename_gpt_parts(blk_dev_desc, argv[1], argv[4], argv[5]);
856  #endif
857  	} else {
858  		return CMD_RET_USAGE;
859  	}
860  
861  	if (ret) {
862  		printf("error!\n");
863  		return CMD_RET_FAILURE;
864  	}
865  
866  	printf("success!\n");
867  	return CMD_RET_SUCCESS;
868  }
869  
870  U_BOOT_CMD(gpt, CONFIG_SYS_MAXARGS, 1, do_gpt,
871  	"GUID Partition Table",
872  	"<command> <interface> <dev> <partitions_list>\n"
873  	" - GUID partition table restoration and validity check\n"
874  	" Restore or verify GPT information on a device connected\n"
875  	" to interface\n"
876  	" Example usage:\n"
877  	" gpt write mmc 0 $partitions\n"
878  	" gpt verify mmc 0 $partitions\n"
879  	" read <interface> <dev>\n"
880  	"    - read GPT into a data structure for manipulation\n"
881  	" guid <interface> <dev>\n"
882  	"    - print disk GUID\n"
883  	" guid <interface> <dev> <varname>\n"
884  	"    - set environment variable to disk GUID\n"
885  	" Example usage:\n"
886  	" gpt guid mmc 0\n"
887  	" gpt guid mmc 0 varname\n"
888  #ifdef CONFIG_CMD_GPT_RENAME
889  	"gpt partition renaming commands:\n"
890  	"gpt swap <interface> <dev> <name1> <name2>\n"
891  	"    - change all partitions named name1 to name2\n"
892  	"      and vice-versa\n"
893  	"gpt rename <interface> <dev> <part> <name>\n"
894  	"    - rename the specified partition\n"
895  	" Example usage:\n"
896  	" gpt swap mmc 0 foo bar\n"
897  	" gpt rename mmc 0 3 foo\n"
898  #endif
899  );
900