132 lines
3.3 KiB
C
132 lines
3.3 KiB
C
/* btrfs.c - B-tree file system. */
|
|
/*
|
|
* GRUB -- GRand Unified Bootloader
|
|
* Copyright (C) 2010 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/err.h>
|
|
#include <grub/file.h>
|
|
#include <grub/mm.h>
|
|
#include <grub/misc.h>
|
|
#include <grub/disk.h>
|
|
#include <grub/dl.h>
|
|
#include <grub/types.h>
|
|
|
|
#define BTRFS_SIGNATURE "_BHRfS_M"
|
|
|
|
struct btrfs_superblock
|
|
{
|
|
grub_uint8_t dummy1[32];
|
|
grub_uint16_t uuid[8];
|
|
grub_uint8_t dummy2[16];
|
|
grub_uint8_t signature[sizeof (BTRFS_SIGNATURE) - 1];
|
|
} __attribute__ ((packed));
|
|
|
|
struct grub_btrfs_data
|
|
{
|
|
struct btrfs_superblock sblock;
|
|
};
|
|
|
|
static struct grub_btrfs_data *
|
|
grub_btrfs_mount (grub_disk_t disk)
|
|
{
|
|
struct grub_btrfs_data *data = grub_malloc (sizeof (*data));
|
|
if (! data)
|
|
return NULL;
|
|
|
|
if (grub_disk_read (disk, 128, 0, sizeof (data->sblock),
|
|
&data->sblock) != GRUB_ERR_NONE)
|
|
goto fail;
|
|
|
|
if (grub_memcmp ((char *) data->sblock.signature, BTRFS_SIGNATURE, sizeof (BTRFS_SIGNATURE) - 1))
|
|
{
|
|
grub_error (GRUB_ERR_BAD_FS, "not a Btrfs filesystem");
|
|
goto fail;
|
|
}
|
|
|
|
return data;
|
|
|
|
fail:
|
|
grub_free (data);
|
|
return NULL;
|
|
}
|
|
|
|
static grub_err_t
|
|
grub_btrfs_open (struct grub_file *file __attribute__ ((unused)),
|
|
const char *name __attribute__ ((unused)))
|
|
{
|
|
return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET, "only detection is supported for Btrfs");
|
|
}
|
|
|
|
static grub_err_t
|
|
grub_btrfs_dir (grub_device_t device,
|
|
const char *path __attribute__ ((unused)),
|
|
int (*hook) (const char *filename,
|
|
const struct grub_dirhook_info *info)
|
|
__attribute__ ((unused)))
|
|
{
|
|
struct grub_btrfs_data *data = grub_btrfs_mount (device->disk);
|
|
if (grub_errno)
|
|
return grub_errno;
|
|
|
|
grub_free (data);
|
|
|
|
return GRUB_ERR_NONE;
|
|
}
|
|
|
|
static grub_err_t
|
|
grub_btrfs_uuid (grub_device_t device, char **uuid)
|
|
{
|
|
struct grub_btrfs_data *data;
|
|
|
|
*uuid = NULL;
|
|
|
|
data = grub_btrfs_mount (device->disk);
|
|
if (! data)
|
|
return grub_errno;
|
|
|
|
*uuid = grub_xasprintf ("%04x%04x-%04x-%04x-%04x-%04x%04x%04x",
|
|
grub_be_to_cpu16 (data->sblock.uuid[0]),
|
|
grub_be_to_cpu16 (data->sblock.uuid[1]),
|
|
grub_be_to_cpu16 (data->sblock.uuid[2]),
|
|
grub_be_to_cpu16 (data->sblock.uuid[3]),
|
|
grub_be_to_cpu16 (data->sblock.uuid[4]),
|
|
grub_be_to_cpu16 (data->sblock.uuid[5]),
|
|
grub_be_to_cpu16 (data->sblock.uuid[6]),
|
|
grub_be_to_cpu16 (data->sblock.uuid[7]));
|
|
|
|
grub_free (data);
|
|
|
|
return grub_errno;
|
|
}
|
|
|
|
static struct grub_fs grub_btrfs_fs =
|
|
{
|
|
.name = "btrfs",
|
|
.dir = grub_btrfs_dir,
|
|
.open = grub_btrfs_open,
|
|
.uuid = grub_btrfs_uuid,
|
|
};
|
|
|
|
GRUB_MOD_INIT(btrfs)
|
|
{
|
|
grub_fs_register (&grub_btrfs_fs);
|
|
}
|
|
|
|
GRUB_MOD_FINI(btrfs)
|
|
{
|
|
grub_fs_unregister (&grub_btrfs_fs);
|
|
}
|