blob: 02a65f0f8b6ab44d9fba1ef4b2a378e933780405 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* cmd_gpt.c -- GPT (GUID Partition Table) handling command
*
* Copyright (C) 2015
* Lukasz Majewski <l.majewski@majess.pl>
*
* Copyright (C) 2012 Samsung Electronics
* author: Lukasz Majewski <l.majewski@samsung.com>
* author: Piotr Wilczek <p.wilczek@samsung.com>
*/
#include <common.h>
#include <malloc.h>
#include <command.h>
#include <part_efi.h>
#include <exports.h>
#include <linux/ctype.h>
#include <div64.h>
#include <memalign.h>
#include <linux/compat.h>
#include <linux/sizes.h>
#include <stdlib.h>
static LIST_HEAD(disk_partitions);
/**
* extract_env(): Expand env name from string format '&{env_name}'
* and return pointer to the env (if the env is set)
*
* @param str - pointer to string
* @param env - pointer to pointer to extracted env
*
* @return - zero on successful expand and env is set
*/
static int extract_env(const char *str, char **env)
{
int ret = -1;
char *e, *s;
#ifdef CONFIG_RANDOM_UUID
char uuid_str[UUID_STR_LEN + 1];
#endif
if (!str || strlen(str) < 4)
return -1;
if (!((strncmp(str, "${", 2) == 0) && (str[strlen(str) - 1] == '}')))
return -1;
s = strdup(str);
if (s == NULL)
return -1;
memset(s + strlen(s) - 1, '\0', 1);
memmove(s, s + 2, strlen(s) - 1);
e = env_get(s);
if (e == NULL) {
#ifdef CONFIG_RANDOM_UUID
debug("%s unset. ", str);
gen_rand_uuid_str(uuid_str, UUID_STR_FORMAT_GUID);
env_set(s, uuid_str);
e = env_get(s);
if (e) {
debug("Set to random.\n");
ret = 0;
} else {
debug("Can't get random UUID.\n");
}
#else
debug("%s unset.\n", str);
#endif
} else {
debug("%s get from environment.\n", str);
ret = 0;
}
*env = e;
free(s);
return ret;
}
/**
* extract_val(): Extract value from a key=value pair list (comma separated).
* Only value for the given key is returend.
* Function allocates memory for the value, remember to free!
*
* @param str - pointer to string with key=values pairs
* @param key - pointer to the key to search for
*
* @return - pointer to allocated string with the value
*/
static char *extract_val(const char *str, const char *key)
{
char *v, *k;
char *s, *strcopy;
char *new = NULL;
strcopy = strdup(str);
if (strcopy == NULL)
return NULL;
s = strcopy;
while (s) {
v = strsep(&s, ",");
if (!v)
break;
k = strsep(&v, "=");
if (!k)
break;
if (strcmp(k, key) == 0) {
new = strdup(v);
break;
}
}
free(strcopy);
return new;
}
/**
* found_key(): Found key without value in parameter list (comma separated).
*
* @param str - pointer to string with key
* @param key - pointer to the key to search for
*
* @return - true on found key
*/
static bool found_key(const char *str, const char *key)
{
char *k;
char *s, *strcopy;
bool result = false;
strcopy = strdup(str);
if (!strcopy)
return NULL;
s = strcopy;
while (s) {
k = strsep(&s, ",");
if (!k)
break;
if (strcmp(k, key) == 0) {
result = true;
break;
}
}
free(strcopy);
return result;
}
static int calc_parts_list_len(int numparts)
{
int partlistlen = UUID_STR_LEN + 1 + strlen("uuid_disk=");
/* for the comma */
partlistlen++;
/* per-partition additions; numparts starts at 1, so this should be correct */
partlistlen += numparts * (strlen("name=,") + PART_NAME_LEN + 1);
/* see part.h for definition of struct disk_partition */
partlistlen += numparts * (strlen("start=MiB,") + sizeof(lbaint_t) + 1);
partlistlen += numparts * (strlen("size=MiB,") + sizeof(lbaint_t) + 1);
partlistlen += numparts * (strlen("uuid=;") + UUID_STR_LEN + 1);
/* for the terminating null */
partlistlen++;
debug("Length of partitions_list is %d for %d partitions\n", partlistlen,
numparts);
return partlistlen;
}
#ifdef CONFIG_CMD_GPT_RENAME
static void del_gpt_info(void)
{
struct list_head *pos = &disk_partitions;
struct disk_part *curr;
while (!list_empty(pos)) {
curr = list_entry(pos->next, struct disk_part, list);
list_del(pos->next);
free(curr);
}
}
static struct disk_part *allocate_disk_part(disk_partition_t *info, int partnum)
{
struct disk_part *newpart;
newpart = calloc(1, sizeof(struct disk_part));
if (!newpart)
return ERR_PTR(-ENOMEM);
newpart->gpt_part_info.start = info->start;
newpart->gpt_part_info.size = info->size;
newpart->gpt_part_info.blksz = info->blksz;
strncpy((char *)newpart->gpt_part_info.name, (const char *)info->name,
PART_NAME_LEN);
newpart->gpt_part_info.name[PART_NAME_LEN - 1] = '\0';
strncpy((char *)newpart->gpt_part_info.type, (const char *)info->type,
PART_TYPE_LEN);
newpart->gpt_part_info.type[PART_TYPE_LEN - 1] = '\0';
newpart->gpt_part_info.bootable = info->bootable;
#ifdef CONFIG_PARTITION_UUIDS
strncpy(newpart->gpt_part_info.uuid, (const char *)info->uuid,
UUID_STR_LEN);
/* UUID_STR_LEN is correct, as uuid[]'s length is UUID_STR_LEN+1 chars */
newpart->gpt_part_info.uuid[UUID_STR_LEN] = '\0';
#endif
newpart->partnum = partnum;
return newpart;
}
static void prettyprint_part_size(char *sizestr, lbaint_t partsize,
lbaint_t blksize)
{
unsigned long long partbytes, partmegabytes;
partbytes = partsize * blksize;
partmegabytes = lldiv(partbytes, SZ_1M);
snprintf(sizestr, 16, "%lluMiB", partmegabytes);
}
static void print_gpt_info(void)
{
struct list_head *pos;
struct disk_part *curr;
char partstartstr[16];
char partsizestr[16];
list_for_each(pos, &disk_partitions) {
curr = list_entry(pos, struct disk_part, list);
prettyprint_part_size(partstartstr, curr->gpt_part_info.start,
curr->gpt_part_info.blksz);
prettyprint_part_size(partsizestr, curr->gpt_part_info.size,
curr->gpt_part_info.blksz);
printf("Partition %d:\n", curr->partnum);
printf("Start %s, size %s\n", partstartstr, partsizestr);
printf("Block size %lu, name %s\n", curr->gpt_part_info.blksz,
curr->gpt_part_info.name);
printf("Type %s, bootable %d\n", curr->gpt_part_info.type,
curr->gpt_part_info.bootable);
#ifdef CONFIG_PARTITION_UUIDS
printf("UUID %s\n", curr->gpt_part_info.uuid);
#endif
printf("\n");
}
}
/*
* create the string that upstream 'gpt write' command will accept as an
* argument
*
* From doc/README.gpt, Format of partitions layout:
* "uuid_disk=...;name=u-boot,size=60MiB,uuid=...;
* name=kernel,size=60MiB,uuid=...;"
* The fields 'name' and 'size' are mandatory for every partition.
* The field 'start' is optional. The fields 'uuid' and 'uuid_disk'
* are optional if CONFIG_RANDOM_UUID is enabled.
*/
static int create_gpt_partitions_list(int numparts, const char *guid,
char *partitions_list)
{
struct list_head *pos;
struct disk_part *curr;
char partstr[PART_NAME_LEN + 1];
if (!partitions_list)
return -EINVAL;
strcpy(partitions_list, "uuid_disk=");
strncat(partitions_list, guid, UUID_STR_LEN + 1);
strcat(partitions_list, ";");
list_for_each(pos, &disk_partitions) {
curr = list_entry(pos, struct disk_part, list);
strcat(partitions_list, "name=");
strncat(partitions_list, (const char *)curr->gpt_part_info.name,
PART_NAME_LEN + 1);
sprintf(partstr, ",start=0x%llx",
(unsigned long long)curr->gpt_part_info.start *
curr->gpt_part_info.blksz);
/* one extra byte for NULL */
strncat(partitions_list, partstr, PART_NAME_LEN + 1);
sprintf(partstr, ",size=0x%llx",
(unsigned long long)curr->gpt_part_info.size *
curr->gpt_part_info.blksz);
strncat(partitions_list, partstr, PART_NAME_LEN + 1);
strcat(partitions_list, ",uuid=");
strncat(partitions_list, curr->gpt_part_info.uuid,
UUID_STR_LEN + 1);
strcat(partitions_list, ";");
}
return 0;
}
/*
* read partition info into disk_partitions list where
* it can be printed or modified
*/
static int get_gpt_info(struct blk_desc *dev_desc)
{
/* start partition numbering at 1, as U-Boot does */
int valid_parts = 0, p, ret;
disk_partition_t info;
struct disk_part *new_disk_part;
/*
* Always re-read partition info from device, in case
* it has changed
*/
INIT_LIST_HEAD(&disk_partitions);
for (p = 1; p <= MAX_SEARCH_PARTITIONS; p++) {
ret = part_get_info(dev_desc, p, &info);
if (ret)
continue;
/* Add 1 here because counter is zero-based but p1 is
the first partition */
new_disk_part = allocate_disk_part(&info, valid_parts+1);
if (IS_ERR(new_disk_part))
goto out;
list_add_tail(&new_disk_part->list, &disk_partitions);
valid_parts++;
}
if (valid_parts == 0) {
printf("** No valid partitions found **\n");
goto out;
}
return valid_parts;
out:
if (valid_parts >= 1)
del_gpt_info();
return -ENODEV;
}
/* a wrapper to test get_gpt_info */
static int do_get_gpt_info(struct blk_desc *dev_desc)
{
int ret;
ret = get_gpt_info(dev_desc);
if (ret > 0) {
print_gpt_info();
del_gpt_info();
return 0;
}
return ret;
}
#endif
/**
* set_gpt_info(): Fill partition information from string
* function allocates memory, remember to free!
*
* @param dev_desc - pointer block device descriptor
* @param str_part - pointer to string with partition information
* @param str_disk_guid - pointer to pointer to allocated string with disk guid
* @param partitions - pointer to pointer to allocated partitions array
* @param parts_count - number of partitions
*
* @return - zero on success, otherwise error
*
*/
static int set_gpt_info(struct blk_desc *dev_desc,
const char *str_part,
char **str_disk_guid,
disk_partition_t **partitions,
u8 *parts_count)
{
char *tok, *str, *s;
int i;
char *val, *p;
int p_count;
disk_partition_t *parts;
int errno = 0;
uint64_t size_ll, start_ll;
lbaint_t offset = 0;
int max_str_part = calc_parts_list_len(MAX_SEARCH_PARTITIONS);
debug("%s: lba num: 0x%x %d\n", __func__,
(unsigned int)dev_desc->lba, (unsigned int)dev_desc->lba);
if (str_part == NULL)
return -1;
str = strdup(str_part);
if (str == NULL)
return -ENOMEM;
/* extract disk guid */
s = str;
val = extract_val(str, "uuid_disk");
if (!val) {
#ifdef CONFIG_RANDOM_UUID
*str_disk_guid = malloc(UUID_STR_LEN + 1);
if (*str_disk_guid == NULL)
return -ENOMEM;
gen_rand_uuid_str(*str_disk_guid, UUID_STR_FORMAT_STD);
#else
free(str);
return -2;
#endif
} else {
val = strsep(&val, ";");
if (extract_env(val, &p))
p = val;
*str_disk_guid = strdup(p);
free(val);
/* Move s to first partition */
strsep(&s, ";");
}
if (s == NULL) {
printf("Error: is the partitions string NULL-terminated?\n");
return -EINVAL;
}
if (strnlen(s, max_str_part) == 0)
return -3;
i = strnlen(s, max_str_part) - 1;
if (s[i] == ';')
s[i] = '\0';
/* calculate expected number of partitions */
p_count = 1;
p = s;
while (*p) {
if (*p++ == ';')
p_count++;
}
/* allocate memory for partitions */
parts = calloc(sizeof(disk_partition_t), p_count);
if (parts == NULL)
return -ENOMEM;
/* retrieve partitions data from string */
for (i = 0; i < p_count; i++) {
tok = strsep(&s, ";");
if (tok == NULL)
break;
/* uuid */
val = extract_val(tok, "uuid");
if (!val) {
/* 'uuid' is optional if random uuid's are enabled */
#ifdef CONFIG_RANDOM_UUID
gen_rand_uuid_str(parts[i].uuid, UUID_STR_FORMAT_STD);
#else
errno = -4;
goto err;
#endif
} else {
if (extract_env(val, &p))
p = val;
if (strnlen(p, max_str_part) >= sizeof(parts[i].uuid)) {
printf("Wrong uuid format for partition %d\n", i);
errno = -4;
goto err;
}
strncpy((char *)parts[i].uuid, p, max_str_part);
free(val);
}
#ifdef CONFIG_PARTITION_TYPE_GUID
/* guid */
val = extract_val(tok, "type");
if (val) {
/* 'type' is optional */
if (extract_env(val, &p))
p = val;
if (strnlen(p, max_str_part) >= sizeof(parts[i].type_guid)) {
printf("Wrong type guid format for partition %d\n",
i);
errno = -4;
goto err;
}
strncpy((char *)parts[i].type_guid, p, max_str_part);
free(val);
}
#endif
/* name */
val = extract_val(tok, "name");
if (!val) { /* name is mandatory */
errno = -4;
goto err;
}
if (extract_env(val, &p))
p = val;
if (strnlen(p, max_str_part) >= sizeof(parts[i].name)) {
errno = -4;
goto err;
}
strncpy((char *)parts[i].name, p, max_str_part);
free(val);
/* size */
val = extract_val(tok, "size");
if (!val) { /* 'size' is mandatory */
errno = -4;
goto err;
}
if (extract_env(val, &p))
p = val;
if ((strcmp(p, "-") == 0)) {
/* Let part efi module to auto extend the size */
parts[i].size = 0;
} else {
size_ll = ustrtoull(p, &p, 0);
parts[i].size = lldiv(size_ll, dev_desc->blksz);
}
free(val);
/* start address */
val = extract_val(tok, "start");
if (val) { /* start address is optional */
if (extract_env(val, &p))
p = val;
start_ll = ustrtoull(p, &p, 0);
parts[i].start = lldiv(start_ll, dev_desc->blksz);
free(val);
}
offset += parts[i].size + parts[i].start;
/* bootable */
if (found_key(tok, "bootable"))
parts[i].bootable = 1;
}
*parts_count = p_count;
*partitions = parts;
free(str);
return 0;
err:
free(str);
free(*str_disk_guid);
free(parts);
return errno;
}
static int gpt_default(struct blk_desc *blk_dev_desc, const char *str_part)
{
int ret;
char *str_disk_guid;
u8 part_count = 0;
disk_partition_t *partitions = NULL;
if (!str_part)
return -1;
/* fill partitions */
ret = set_gpt_info(blk_dev_desc, str_part,
&str_disk_guid, &partitions, &part_count);
if (ret) {
if (ret == -1)
printf("No partition list provided\n");
if (ret == -2)
printf("Missing disk guid\n");
if ((ret == -3) || (ret == -4))
printf("Partition list incomplete\n");
return -1;
}
/* save partitions layout to disk */
ret = gpt_restore(blk_dev_desc, str_disk_guid, partitions, part_count);
free(str_disk_guid);
free(partitions);
return ret;
}
static int gpt_verify(struct blk_desc *blk_dev_desc, const char *str_part)
{
ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1,
blk_dev_desc->blksz);
disk_partition_t *partitions = NULL;
gpt_entry *gpt_pte = NULL;
char *str_disk_guid;
u8 part_count = 0;
int ret = 0;
if (!str_part)
return -1;
/* fill partitions */
ret = set_gpt_info(blk_dev_desc, str_part,
&str_disk_guid, &partitions, &part_count);
if (ret) {
if (ret == -1) {
printf("No partition list provided - only basic check\n");
ret = gpt_verify_headers(blk_dev_desc, gpt_head,
&gpt_pte);
goto out;
}
if (ret == -2)
printf("Missing disk guid\n");
if ((ret == -3) || (ret == -4))
printf("Partition list incomplete\n");
return -1;
}
/* Check partition layout with provided pattern */
ret = gpt_verify_partitions(blk_dev_desc, partitions, part_count,
gpt_head, &gpt_pte);
free(str_disk_guid);
free(partitions);
out:
free(gpt_pte);
return ret;
}
static int do_disk_guid(struct blk_desc *dev_desc, char * const namestr)
{
int ret;
char disk_guid[UUID_STR_LEN + 1];
ret = get_disk_guid(dev_desc, disk_guid);
if (ret < 0)
return CMD_RET_FAILURE;
if (namestr)
env_set(namestr, disk_guid);
else
printf("%s\n", disk_guid);
return ret;
}
#ifdef CONFIG_CMD_GPT_RENAME
static int do_rename_gpt_parts(struct blk_desc *dev_desc, char *subcomm,
char *name1, char *name2)
{
struct list_head *pos;
struct disk_part *curr;
disk_partition_t *new_partitions = NULL;
char disk_guid[UUID_STR_LEN + 1];
char *partitions_list, *str_disk_guid = NULL;
u8 part_count = 0;
int partlistlen, ret, numparts = 0, partnum, i = 1, ctr1 = 0, ctr2 = 0;
if ((subcomm == NULL) || (name1 == NULL) || (name2 == NULL) ||
(strcmp(subcomm, "swap") && (strcmp(subcomm, "rename"))))
return -EINVAL;
ret = get_disk_guid(dev_desc, disk_guid);
if (ret < 0)
return ret;
/*
* Allocates disk_partitions, requiring matching call to del_gpt_info()
* if successful.
*/
numparts = get_gpt_info(dev_desc);
if (numparts <= 0)
return numparts ? numparts : -ENODEV;
partlistlen = calc_parts_list_len(numparts);
partitions_list = malloc(partlistlen);
if (!partitions_list) {
del_gpt_info();
return -ENOMEM;
}
memset(partitions_list, '\0', partlistlen);
ret = create_gpt_partitions_list(numparts, disk_guid, partitions_list);
if (ret < 0) {
free(partitions_list);
return ret;
}
/*
* Uncomment the following line to print a string that 'gpt write'
* or 'gpt verify' will accept as input.
*/
debug("OLD partitions_list is %s with %u chars\n", partitions_list,
(unsigned)strlen(partitions_list));
/* set_gpt_info allocates new_partitions and str_disk_guid */
ret = set_gpt_info(dev_desc, partitions_list, &str_disk_guid,
&new_partitions, &part_count);
if (ret < 0)
goto out;
if (!strcmp(subcomm, "swap")) {
if ((strlen(name1) > PART_NAME_LEN) || (strlen(name2) > PART_NAME_LEN)) {
printf("Names longer than %d characters are truncated.\n", PART_NAME_LEN);
ret = -EINVAL;
goto out;
}
list_for_each(pos, &disk_partitions) {
curr = list_entry(pos, struct disk_part, list);
if (!strcmp((char *)curr->gpt_part_info.name, name1)) {
strcpy((char *)curr->gpt_part_info.name, name2);
ctr1++;
} else if (!strcmp((char *)curr->gpt_part_info.name, name2)) {
strcpy((char *)curr->gpt_part_info.name, name1);
ctr2++;
}
}
if ((ctr1 + ctr2 < 2) || (ctr1 != ctr2)) {
printf("Cannot swap partition names except in pairs.\n");
ret = -EINVAL;
goto out;
}
} else { /* rename */
if (strlen(name2) > PART_NAME_LEN) {
printf("Names longer than %d characters are truncated.\n", PART_NAME_LEN);
ret = -EINVAL;
goto out;
}
partnum = (int)simple_strtol(name1, NULL, 10);
if ((partnum < 0) || (partnum > numparts)) {
printf("Illegal partition number %s\n", name1);
ret = -EINVAL;
goto out;
}
ret = part_get_info(dev_desc, partnum, new_partitions);
if (ret < 0)
goto out;
/* U-Boot partition numbering starts at 1 */
list_for_each(pos, &disk_partitions) {
curr = list_entry(pos, struct disk_part, list);
if (i == partnum) {
strcpy((char *)curr->gpt_part_info.name, name2);
break;
}
i++;
}
}
ret = create_gpt_partitions_list(numparts, disk_guid, partitions_list);
if (ret < 0)
goto out;
debug("NEW partitions_list is %s with %u chars\n", partitions_list,
(unsigned)strlen(partitions_list));
ret = set_gpt_info(dev_desc, partitions_list, &str_disk_guid,
&new_partitions, &part_count);
/*
* Even though valid pointers are here passed into set_gpt_info(),
* it mallocs again, and there's no way to tell which failed.
*/
if (ret < 0)
goto out;
debug("Writing new partition table\n");
ret = gpt_restore(dev_desc, disk_guid, new_partitions, numparts);
if (ret < 0) {
printf("Writing new partition table failed\n");
goto out;
}
debug("Reading back new partition table\n");
/*
* Empty the existing disk_partitions list, as otherwise the memory in
* the original list is unreachable.
*/
del_gpt_info();
numparts = get_gpt_info(dev_desc);
if (numparts <= 0) {
ret = numparts ? numparts : -ENODEV;
goto out;
}
printf("new partition table with %d partitions is:\n", numparts);
print_gpt_info();
out:
del_gpt_info();
#ifdef CONFIG_RANDOM_UUID
if (str_disk_guid)
free(str_disk_guid);
#endif
if (new_partitions)
free(new_partitions);
free(partitions_list);
return ret;
}
#endif
/**
* do_gpt(): Perform GPT operations
*
* @param cmdtp - command name
* @param flag
* @param argc
* @param argv
*
* @return zero on success; otherwise error
*/
static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
int ret = CMD_RET_SUCCESS;
int dev = 0;
char *ep;
struct blk_desc *blk_dev_desc = NULL;
#ifndef CONFIG_CMD_GPT_RENAME
if (argc < 4 || argc > 5)
#else
if (argc < 4 || argc > 6)
#endif
return CMD_RET_USAGE;
dev = (int)simple_strtoul(argv[3], &ep, 10);
if (!ep || ep[0] != '\0') {
printf("'%s' is not a number\n", argv[3]);
return CMD_RET_USAGE;
}
blk_dev_desc = blk_get_dev(argv[2], dev);
if (!blk_dev_desc) {
printf("%s: %s dev %d NOT available\n",
__func__, argv[2], dev);
return CMD_RET_FAILURE;
}
if ((strcmp(argv[1], "write") == 0) && (argc == 5)) {
printf("Writing GPT: ");
ret = gpt_default(blk_dev_desc, argv[4]);
} else if ((strcmp(argv[1], "verify") == 0)) {
ret = gpt_verify(blk_dev_desc, argv[4]);
printf("Verify GPT: ");
} else if (strcmp(argv[1], "guid") == 0) {
ret = do_disk_guid(blk_dev_desc, argv[4]);
#ifdef CONFIG_CMD_GPT_RENAME
} else if (strcmp(argv[1], "read") == 0) {
ret = do_get_gpt_info(blk_dev_desc);
} else if ((strcmp(argv[1], "swap") == 0) ||
(strcmp(argv[1], "rename") == 0)) {
ret = do_rename_gpt_parts(blk_dev_desc, argv[1], argv[4], argv[5]);
#endif
} else {
return CMD_RET_USAGE;
}
if (ret) {
printf("error!\n");
return CMD_RET_FAILURE;
}
printf("success!\n");
return CMD_RET_SUCCESS;
}
U_BOOT_CMD(gpt, CONFIG_SYS_MAXARGS, 1, do_gpt,
"GUID Partition Table",
"<command> <interface> <dev> <partitions_list>\n"
" - GUID partition table restoration and validity check\n"
" Restore or verify GPT information on a device connected\n"
" to interface\n"
" Example usage:\n"
" gpt write mmc 0 $partitions\n"
" gpt verify mmc 0 $partitions\n"
" read <interface> <dev>\n"
" - read GPT into a data structure for manipulation\n"
" guid <interface> <dev>\n"
" - print disk GUID\n"
" guid <interface> <dev> <varname>\n"
" - set environment variable to disk GUID\n"
" Example usage:\n"
" gpt guid mmc 0\n"
" gpt guid mmc 0 varname\n"
#ifdef CONFIG_CMD_GPT_RENAME
"gpt partition renaming commands:\n"
"gpt swap <interface> <dev> <name1> <name2>\n"
" - change all partitions named name1 to name2\n"
" and vice-versa\n"
"gpt rename <interface> <dev> <part> <name>\n"
" - rename the specified partition\n"
" Example usage:\n"
" gpt swap mmc 0 foo bar\n"
" gpt rename mmc 0 3 foo\n"
#endif
);