btrfs-progs/btrfstune.c

127 lines
2.7 KiB
C

/*
* Copyright (C) 2008 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.
*/
#define _XOPEN_SOURCE 500
#define _GNU_SOURCE 1
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <dirent.h>
#include "kerncompat.h"
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "utils.h"
#include "version.h"
static char *device;
int update_seeding_flag(struct btrfs_root *root, int set_flag)
{
struct btrfs_trans_handle *trans;
struct btrfs_super_block *disk_super;
u64 super_flags;
disk_super = &root->fs_info->super_copy;
super_flags = btrfs_super_flags(disk_super);
if (set_flag) {
if (super_flags & BTRFS_SUPER_FLAG_SEEDING) {
fprintf(stderr, "seeding flag is already set on %s\n",
device);
return 1;
}
super_flags |= BTRFS_SUPER_FLAG_SEEDING;
} else {
if (!(super_flags & BTRFS_SUPER_FLAG_SEEDING)) {
fprintf(stderr, "seeding flag is not set on %s\n",
device);
return 1;
}
super_flags &= ~BTRFS_SUPER_FLAG_SEEDING;
}
trans = btrfs_start_transaction(root, 1);
btrfs_set_super_flags(disk_super, super_flags);
btrfs_commit_transaction(trans, root);
return 0;
}
static void print_usage(void)
{
fprintf(stderr, "usage: btrfstune [options] device\n");
fprintf(stderr, "\t-S value\tenable/disable seeding\n");
}
int main(int argc, char *argv[])
{
struct btrfs_root *root;
int success = 0;
int seeding_flag = 0;
int seeding_value = 0;
int ret;
while(1) {
int c = getopt(argc, argv, "S:");
if (c < 0)
break;
switch(c) {
case 'S':
seeding_flag = 1;
seeding_value = atoi(optarg);
break;
default:
print_usage();
return 1;
}
}
argc = argc - optind;
device = argv[optind];
if (argc != 1) {
print_usage();
return 1;
}
if (check_mounted(device)) {
fprintf(stderr, "%s is mounted\n", device);
return 1;
}
root = open_ctree(device, 0, 1);
if (seeding_flag) {
ret = update_seeding_flag(root, seeding_value);
if (!ret)
success++;
}
if (success > 0) {
ret = 0;
} else {
root->fs_info->readonly = 1;
ret = 1;
}
close_ctree(root);
return ret;
}