/* * 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 #include #include #include #include #include "kerncompat.h" #include "ctree.h" #include "volumes.h" #include "disk-io.h" #include "print-tree.h" #include "transaction.h" #include "list.h" #include "utils.h" #include "help.h" static void print_usage(void) { printf("usage: btrfs-select-super -s number dev\n"); printf("\t-s super copy of superblock to overwrite the primary one (values: 1, 2)\n"); exit(1); } 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) { fprintf(stderr, "ERROR: super mirror should be less than: %d\n", BTRFS_SUPER_MIRROR_MAX); exit(1); } bytenr = btrfs_sb_offset(((int)num)); break; default: print_usage(); } } set_argv0(argv); if (check_argc_exact(argc - optind, 1)) print_usage(); if (bytenr == 0) { fprintf(stderr, "Please select the super copy with -s\n"); print_usage(); } radix_tree_init(); 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) { fprintf(stderr, "Open ctree failed\n"); 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", (unsigned long long)num, (unsigned long long)bytenr); close_ctree(root); btrfs_close_all_devices(); return ret; }