grub/grub-core/commands/gptsync.c
2013-10-25 18:02:40 +02:00

264 lines
7.3 KiB
C
Raw Permalink Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/* gptsync.c - fill the mbr based on gpt entries */
/* XXX: I don't know what to do if sector size isn't 512 bytes */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2009 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/command.h>
#include <grub/dl.h>
#include <grub/device.h>
#include <grub/disk.h>
#include <grub/msdos_partition.h>
#include <grub/partition.h>
#include <grub/misc.h>
#include <grub/mm.h>
#include <grub/fs.h>
#include <grub/i18n.h>
GRUB_MOD_LICENSE ("GPLv3+");
/* Convert a LBA address to a CHS address in the INT 13 format. */
/* Taken from grub1. */
/* XXX: use hardcoded geometry of C = 1024, H = 255, S = 63.
Is it a problem?
*/
static void
lba_to_chs (grub_uint32_t lba, grub_uint8_t *cl, grub_uint8_t *ch,
grub_uint8_t *dh)
{
grub_uint32_t cylinder, head, sector;
grub_uint32_t sectors = 63, heads = 255, cylinders = 1024;
sector = lba % sectors + 1;
head = (lba / sectors) % heads;
cylinder = lba / (sectors * heads);
if (cylinder >= cylinders)
{
*cl = *ch = *dh = 0xff;
return;
}
*cl = sector | ((cylinder & 0x300) >> 2);
*ch = cylinder & 0xFF;
*dh = head;
}
static grub_err_t
grub_cmd_gptsync (grub_command_t cmd __attribute__ ((unused)),
int argc, char **args)
{
grub_device_t dev;
struct grub_msdos_partition_mbr mbr;
struct grub_partition *partition;
grub_disk_addr_t first_sector;
int numactive = 0;
int i;
if (argc < 1)
return grub_error (GRUB_ERR_BAD_ARGUMENT, "device name required");
if (argc > 4)
return grub_error (GRUB_ERR_BAD_ARGUMENT, "only 3 partitions can be "
"in hybrid MBR");
if (args[0][0] == '(' && args[0][grub_strlen (args[0]) - 1] == ')')
{
args[0][grub_strlen (args[0]) - 1] = 0;
dev = grub_device_open (args[0] + 1);
args[0][grub_strlen (args[0])] = ')';
}
else
dev = grub_device_open (args[0]);
if (! dev)
return grub_errno;
if (! dev->disk)
{
grub_device_close (dev);
return grub_error (GRUB_ERR_BAD_ARGUMENT, "not a disk");
}
/* Read the protective MBR. */
if (grub_disk_read (dev->disk, 0, 0, sizeof (mbr), &mbr))
{
grub_device_close (dev);
return grub_errno;
}
/* Check if it is valid. */
if (mbr.signature != grub_cpu_to_le16 (GRUB_PC_PARTITION_SIGNATURE))
{
grub_device_close (dev);
return grub_error (GRUB_ERR_BAD_PART_TABLE, "no signature");
}
/* Make sure the MBR is a protective MBR and not a normal MBR. */
for (i = 0; i < 4; i++)
if (mbr.entries[i].type == GRUB_PC_PARTITION_TYPE_GPT_DISK)
break;
if (i == 4)
{
grub_device_close (dev);
return grub_error (GRUB_ERR_BAD_PART_TABLE, "no GPT partition map found");
}
first_sector = dev->disk->total_sectors;
for (i = 1; i < argc; i++)
{
char *separator, csep = 0;
grub_uint8_t type;
separator = grub_strchr (args[i], '+');
if (! separator)
separator = grub_strchr (args[i], '-');
if (separator)
{
csep = *separator;
*separator = 0;
}
partition = grub_partition_probe (dev->disk, args[i]);
if (separator)
*separator = csep;
if (! partition)
{
grub_device_close (dev);
return grub_error (GRUB_ERR_UNKNOWN_DEVICE,
N_("no such partition"));
}
if (partition->start + partition->len > 0xffffffff)
{
grub_device_close (dev);
return grub_error (GRUB_ERR_OUT_OF_RANGE,
"only partitions residing in the first 2TB "
"can be present in hybrid MBR");
}
if (first_sector > partition->start)
first_sector = partition->start;
if (separator && *(separator + 1))
type = grub_strtoul (separator + 1, 0, 0);
else
{
grub_fs_t fs = 0;
dev->disk->partition = partition;
fs = grub_fs_probe (dev);
/* Unknown filesystem isn't fatal. */
if (grub_errno == GRUB_ERR_UNKNOWN_FS)
{
fs = 0;
grub_errno = GRUB_ERR_NONE;
}
if (fs && grub_strcmp (fs->name, "ntfs") == 0)
type = GRUB_PC_PARTITION_TYPE_NTFS;
else if (fs && grub_strcmp (fs->name, "fat") == 0)
/* FIXME: detect FAT16. */
type = GRUB_PC_PARTITION_TYPE_FAT32_LBA;
else if (fs && (grub_strcmp (fs->name, "hfsplus") == 0
|| grub_strcmp (fs->name, "hfs") == 0))
type = GRUB_PC_PARTITION_TYPE_HFS;
else
/* FIXME: detect more types. */
type = GRUB_PC_PARTITION_TYPE_EXT2FS;
dev->disk->partition = 0;
}
mbr.entries[i].flag = (csep == '+') ? 0x80 : 0;
if (csep == '+')
{
numactive++;
if (numactive == 2)
{
grub_device_close (dev);
return grub_error (GRUB_ERR_BAD_ARGUMENT,
"only one partition can be active");
}
}
mbr.entries[i].type = type;
mbr.entries[i].start = grub_cpu_to_le32 (partition->start);
lba_to_chs (partition->start,
&(mbr.entries[i].start_sector),
&(mbr.entries[i].start_cylinder),
&(mbr.entries[i].start_head));
lba_to_chs (partition->start + partition->len - 1,
&(mbr.entries[i].end_sector),
&(mbr.entries[i].end_cylinder),
&(mbr.entries[i].end_head));
mbr.entries[i].length = grub_cpu_to_le32 (partition->len);
grub_free (partition);
}
for (; i < 4; i++)
grub_memset (&(mbr.entries[i]), 0, sizeof (mbr.entries[i]));
/* The protective partition. */
if (first_sector > 0xffffffff)
first_sector = 0xffffffff;
else
first_sector--;
mbr.entries[0].flag = 0;
mbr.entries[0].type = GRUB_PC_PARTITION_TYPE_GPT_DISK;
mbr.entries[0].start = grub_cpu_to_le32 (1);
lba_to_chs (1,
&(mbr.entries[0].start_sector),
&(mbr.entries[0].start_cylinder),
&(mbr.entries[0].start_head));
lba_to_chs (first_sector,
&(mbr.entries[0].end_sector),
&(mbr.entries[0].end_cylinder),
&(mbr.entries[0].end_head));
mbr.entries[0].length = grub_cpu_to_le32 (first_sector);
mbr.signature = grub_cpu_to_le16 (GRUB_PC_PARTITION_SIGNATURE);
if (grub_disk_write (dev->disk, 0, 0, sizeof (mbr), &mbr))
{
grub_device_close (dev);
return grub_errno;
}
grub_printf_ (N_("New MBR is written to `%s'\n"), args[0]);
return GRUB_ERR_NONE;
}
static grub_command_t cmd;
GRUB_MOD_INIT(gptsync)
{
(void) mod; /* To stop warning. */
cmd = grub_register_command ("gptsync", grub_cmd_gptsync,
N_("DEVICE [PARTITION[+/-[TYPE]]] ..."),
/* TRANSLATORS: MBR type is one-byte partition
type id. */
N_("Fill hybrid MBR of GPT drive DEVICE. "
"Specified partitions will be a part "
"of hybrid MBR. Up to 3 partitions are "
"allowed. TYPE is an MBR type. "
"+ means that partition is active. "
"Only one partition can be active."));
}
GRUB_MOD_FINI(gptsync)
{
grub_unregister_command (cmd);
}