freebsd-dev/sbin/gpt/create.c
Marcel Moolenaar 597c201050 Add an -f option (for force) to the create command. The -f option
allows the user to force the creation of a GPT even when there's a
MBR on the device. The MBR is simply wiped and any partitions
described by it are lost. Without the -f option one cannot create
a GPT when there's a MBR.
2004-11-13 05:13:33 +00:00

246 lines
6.6 KiB
C

/*
* Copyright (c) 2002 Marcel Moolenaar
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <err.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "map.h"
#include "gpt.h"
static int force;
static int primary_only;
static void
usage_create(void)
{
fprintf(stderr,
"usage: %s [-fp] device ...\n", getprogname());
exit(1);
}
static void
create(int fd)
{
uuid_t uuid;
off_t blocks, last;
map_t *gpt, *tpg;
map_t *tbl, *lbt;
map_t *map;
struct mbr *mbr;
struct gpt_hdr *hdr;
struct gpt_ent *ent;
unsigned int i;
last = mediasz / secsz - 1LL;
if (map_find(MAP_TYPE_PRI_GPT_HDR) != NULL ||
map_find(MAP_TYPE_SEC_GPT_HDR) != NULL) {
warnx("%s: error: device already contains a GPT", device_name);
return;
}
map = map_find(MAP_TYPE_MBR);
if (map != NULL) {
if (!force) {
warnx("%s: error: device contains a MBR", device_name);
return;
}
/* Nuke the MBR in our internal map. */
map->map_type = MAP_TYPE_UNUSED;
}
/*
* Create PMBR.
*/
if (map_find(MAP_TYPE_PMBR) == NULL) {
if (map_free(0LL, 1LL) == 0) {
warnx("%s: error: no room for the PMBR", device_name);
return;
}
mbr = gpt_read(fd, 0LL, 1);
bzero(mbr, sizeof(*mbr));
mbr->mbr_sig = htole16(MBR_SIG);
mbr->mbr_part[0].part_shd = 0xff;
mbr->mbr_part[0].part_ssect = 0xff;
mbr->mbr_part[0].part_scyl = 0xff;
mbr->mbr_part[0].part_typ = 0xee;
mbr->mbr_part[0].part_ehd = 0xff;
mbr->mbr_part[0].part_esect = 0xff;
mbr->mbr_part[0].part_ecyl = 0xff;
mbr->mbr_part[0].part_start_lo = htole16(1);
if (last > 0xffffffff) {
mbr->mbr_part[0].part_size_lo = htole16(0xffff);
mbr->mbr_part[0].part_size_hi = htole16(0xffff);
} else {
mbr->mbr_part[0].part_size_lo = htole16(last);
mbr->mbr_part[0].part_size_hi = htole16(last >> 16);
}
map = map_add(0LL, 1LL, MAP_TYPE_PMBR, mbr);
gpt_write(fd, map);
}
/* Get the amount of free space after the MBR */
blocks = map_free(1LL, 0LL);
if (blocks == 0LL) {
warnx("%s: error: no room for the GPT header", device_name);
return;
}
/* Don't create more than parts entries. */
if ((uint64_t)(blocks - 1) * secsz > parts * sizeof(struct gpt_ent)) {
blocks = (parts * sizeof(struct gpt_ent)) / secsz;
if ((parts * sizeof(struct gpt_ent)) % secsz)
blocks++;
blocks++; /* Don't forget the header itself */
}
/* Never cross the median of the device. */
if ((blocks + 1LL) > ((last + 1LL) >> 1))
blocks = ((last + 1LL) >> 1) - 1LL;
/*
* Get the amount of free space at the end of the device and
* calculate the size for the GPT structures.
*/
map = map_last();
if (map->map_type != MAP_TYPE_UNUSED) {
warnx("%s: error: no room for the backup header", device_name);
return;
}
if (map->map_size < blocks)
blocks = map->map_size;
if (blocks == 1LL) {
warnx("%s: error: no room for the GPT table", device_name);
return;
}
blocks--; /* Number of blocks in the GPT table. */
gpt = map_add(1LL, 1LL, MAP_TYPE_PRI_GPT_HDR, calloc(1, secsz));
tbl = map_add(2LL, blocks, MAP_TYPE_PRI_GPT_TBL,
calloc(blocks, secsz));
if (gpt == NULL || tbl == NULL)
return;
hdr = gpt->map_data;
memcpy(hdr->hdr_sig, GPT_HDR_SIG, sizeof(hdr->hdr_sig));
hdr->hdr_revision = htole32(GPT_HDR_REVISION);
/*
* XXX struct gpt_hdr is not a multiple of 8 bytes in size and thus
* contains padding we must not include in the size.
*/
hdr->hdr_size = htole32(offsetof(struct gpt_hdr, padding));
hdr->hdr_lba_self = htole64(gpt->map_start);
hdr->hdr_lba_alt = htole64(last);
hdr->hdr_lba_start = htole64(tbl->map_start + blocks);
hdr->hdr_lba_end = htole64(last - blocks - 1LL);
uuid_create(&uuid, NULL);
le_uuid_enc(&hdr->hdr_uuid, &uuid);
hdr->hdr_lba_table = htole64(tbl->map_start);
hdr->hdr_entries = htole32((blocks * secsz) / sizeof(struct gpt_ent));
if (le32toh(hdr->hdr_entries) > parts)
hdr->hdr_entries = htole32(parts);
hdr->hdr_entsz = htole32(sizeof(struct gpt_ent));
ent = tbl->map_data;
for (i = 0; i < le32toh(hdr->hdr_entries); i++) {
uuid_create(&uuid, NULL);
le_uuid_enc(&ent[i].ent_uuid, &uuid);
}
hdr->hdr_crc_table = htole32(crc32(ent, le32toh(hdr->hdr_entries) *
le32toh(hdr->hdr_entsz)));
hdr->hdr_crc_self = htole32(crc32(hdr, le32toh(hdr->hdr_size)));
gpt_write(fd, gpt);
gpt_write(fd, tbl);
/*
* Create backup GPT if the user didn't suppress it.
*/
if (!primary_only) {
tpg = map_add(last, 1LL, MAP_TYPE_SEC_GPT_HDR,
calloc(1, secsz));
lbt = map_add(last - blocks, blocks, MAP_TYPE_SEC_GPT_TBL,
tbl->map_data);
memcpy(tpg->map_data, gpt->map_data, secsz);
hdr = tpg->map_data;
hdr->hdr_lba_self = htole64(tpg->map_start);
hdr->hdr_lba_alt = htole64(gpt->map_start);
hdr->hdr_lba_table = htole64(lbt->map_start);
hdr->hdr_crc_self = 0; /* Don't ever forget this! */
hdr->hdr_crc_self = htole32(crc32(hdr, le32toh(hdr->hdr_size)));
gpt_write(fd, lbt);
gpt_write(fd, tpg);
}
}
int
cmd_create(int argc, char *argv[])
{
int ch, fd;
while ((ch = getopt(argc, argv, "fp")) != -1) {
switch(ch) {
case 'f':
force = 1;
break;
case 'p':
primary_only = 1;
break;
default:
usage_create();
}
}
if (argc == optind)
usage_create();
while (optind < argc) {
fd = gpt_open(argv[optind++]);
if (fd == -1) {
warn("unable to open device '%s'", device_name);
continue;
}
create(fd);
gpt_close(fd);
}
return (0);
}