btrfs-zero-log.c

   1 /*
   2  * Copyright (C) 2007 Oracle.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #define _XOPEN_SOURCE 500
  20 #define _GNU_SOURCE 1
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <unistd.h>
  24 #include <fcntl.h>
  25 #include <sys/stat.h>
  26 #include "kerncompat.h"
  27 #include "ctree.h"
  28 #include "disk-io.h"
  29 #include "print-tree.h"
  30 #include "transaction.h"
  31 #include "list.h"
  32 #include "version.h"
  33 #include "utils.h"
  34
  35 static void print_usage(void) __attribute__((noreturn));
  36 static void print_usage(void)
  37 {
  38         fprintf(stderr, "usage: btrfs-zero-log dev\n");
  39         fprintf(stderr, "%s\n", BTRFS_BUILD_VERSION);
  40         exit(1);
  41 }
  42
  43 int main(int ac, char **av)
  44 {
  45         struct btrfs_root *root;
  46         struct btrfs_trans_handle *trans;
  47         int ret;
  48
  49         set_argv0(av);
  50         if (check_argc_exact(ac, 2))
  51                 print_usage();
  52
  53         radix_tree_init();
  54
  55         if((ret = check_mounted(av[1])) < 0) {
  56                 fprintf(stderr, "Could not check mount status: %s\n", strerror(-ret));
  57                 goto out;
  58         } else if(ret) {
  59                 fprintf(stderr, "%s is currently mounted. Aborting.\n", av[1]);
  60                 ret = -EBUSY;
  61                 goto out;
  62         }
  63
  64         root = open_ctree(av[1], 0, OPEN_CTREE_WRITES | OPEN_CTREE_PARTIAL);
  65
  66         if (root == NULL)
  67                 return 1;
  68
  69         trans = btrfs_start_transaction(root, 1);
  70         btrfs_set_super_log_root(root->fs_info->super_copy, 0);
  71         btrfs_set_super_log_root_level(root->fs_info->super_copy, 0);
  72         btrfs_commit_transaction(trans, root);
  73         close_ctree(root);
  74         printf("Log root zero'ed\n");
  75 out:
  76         return !!ret;
  77 }