/*

* Copyright (C) 2007 Oracle. All rights reserved.

*

* This program is free software; you can redistribute it and/or

* modify it under the terms of the GNU General Public

* License v2 as published by the Free Software Foundation.

*

* This program 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 this program; if not, write to the

* Free Software Foundation, Inc., 59 Temple Place - Suite 330,

* Boston, MA 021110-1307, USA.

*/

#include "kerncompat.h"

#include <stdio.h>

#include <stdlib.h>

#include <errno.h>

#include <getopt.h>

#include "kernel-shared/ctree.h"

#include "kernel-shared/volumes.h"

#include "kernel-shared/disk-io.h"

#include "common/utils.h"

#include "common/help.h"

#include "common/open-utils.h"

#include "common/messages.h"

#include "common/string-utils.h"

#include "cmds/commands.h"

static const char * const select_super_usage[] = {

"btrfs-select-super -s number dev",

"Overwrite primary superblock by selected copy",

""

OPTLINE("-s super", "copy of superblock to overwrite the primary one (values: 1, 2)"),

NULL

};

static const struct cmd_struct select_super_cmd = {

.usagestr = select_super_usage

};

int main(int argc, char **argv)

{

struct btrfs_root *root;

int ret;

u64 num = 0;

u64 bytenr = 0;

while(1) {

int c;

c = getopt(argc, argv, "s:");

if (c < 0)

break;

switch(c) {

case 's':

num = arg_strtou64(optarg);

if (num >= BTRFS_SUPER_MIRROR_MAX) {

error("super mirror should be less than: %d",

BTRFS_SUPER_MIRROR_MAX);

exit(1);

}

bytenr = btrfs_sb_offset(((int)num));

break;

default:

usage(&select_super_cmd, 1);

}

}

set_argv0(argv);

if (check_argc_exact(argc - optind, 1))

return 1;

if (bytenr == 0) {

error("please select the super copy with -s");

usage(&select_super_cmd, 1);

}

if((ret = check_mounted(argv[optind])) < 0) {

errno = -ret;

error("cannot check mount status: %m");

return ret;

} else if(ret) {

error("%s is currently mounted, aborting", argv[optind]);

return -EBUSY;

}

root = open_ctree(argv[optind], bytenr, 1);

if (!root) {

error("open ctree failed");

return 1;

}

/* make the super writing code think we've read the first super */

root->fs_info->super_bytenr = BTRFS_SUPER_INFO_OFFSET;

ret = write_all_supers(root->fs_info);

/* we don't close the ctree or anything, because we don't want a real

* transaction commit. We just want the super copy we pulled off the

* disk to overwrite all the other copies

*/

printf("using SB copy %llu, bytenr %llu\n", num, bytenr);

close_ctree(root);

btrfs_close_all_devices();

return ret;

}