1/* 2 * volume_id - reads filesystem label and uuid 3 * 4 * Copyright (C) 2006 Red Hat, Inc. <redhat.com> 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License as published by the 8 * Free Software Foundation version 2 of the License. 9 */ 10 11#ifndef _GNU_SOURCE 12#define _GNU_SOURCE 1 13#endif 14 15#ifdef HAVE_CONFIG_H 16# include <config.h> 17#endif 18 19#include <stdio.h> 20#include <stdlib.h> 21#include <unistd.h> 22#include <string.h> 23#include <errno.h> 24#include <ctype.h> 25 26#include "libvolume_id.h" 27#include "util.h" 28 29/* Common gfs/gfs2 constants: */ 30#define GFS_MAGIC 0x01161970 31#define GFS_DEFAULT_BSIZE 4096 32#define GFS_SUPERBLOCK_OFFSET (0x10 * GFS_DEFAULT_BSIZE) 33#define GFS_METATYPE_SB 1 34#define GFS_FORMAT_SB 100 35#define GFS_LOCKNAME_LEN 64 36 37/* gfs1 constants: */ 38#define GFS_FORMAT_FS 1309 39#define GFS_FORMAT_MULTI 1401 40/* gfs2 constants: */ 41#define GFS2_FORMAT_FS 1801 42#define GFS2_FORMAT_MULTI 1900 43 44struct gfs2_meta_header { 45 uint32_t mh_magic; 46 uint32_t mh_type; 47 uint64_t __pad0; /* Was generation number in gfs1 */ 48 uint32_t mh_format; 49 uint32_t __pad1; /* Was incarnation number in gfs1 */ 50}; 51 52struct gfs2_inum { 53 uint64_t no_formal_ino; 54 uint64_t no_addr; 55}; 56 57struct gfs2_sb { 58 struct gfs2_meta_header sb_header; 59 60 uint32_t sb_fs_format; 61 uint32_t sb_multihost_format; 62 uint32_t __pad0; /* Was superblock flags in gfs1 */ 63 64 uint32_t sb_bsize; 65 uint32_t sb_bsize_shift; 66 uint32_t __pad1; /* Was journal segment size in gfs1 */ 67 68 struct gfs2_inum sb_master_dir; /* Was jindex dinode in gfs1 */ 69 struct gfs2_inum __pad2; /* Was rindex dinode in gfs1 */ 70 struct gfs2_inum sb_root_dir; 71 72 char sb_lockproto[GFS_LOCKNAME_LEN]; 73 char sb_locktable[GFS_LOCKNAME_LEN]; 74 /* In gfs1, quota and license dinodes followed */ 75} PACKED; 76 77static int volume_id_probe_gfs_generic(struct volume_id *id, uint64_t off, int vers) 78{ 79 struct gfs2_sb *sbd; 80 81 info("probing at offset 0x%llx", (unsigned long long) off); 82 83 sbd = (struct gfs2_sb *) 84 volume_id_get_buffer(id, off + GFS_SUPERBLOCK_OFFSET, sizeof(struct gfs2_sb)); 85 if (sbd == NULL) 86 return -1; 87 88 if (be32_to_cpu(sbd->sb_header.mh_magic) == GFS_MAGIC && 89 be32_to_cpu(sbd->sb_header.mh_type) == GFS_METATYPE_SB && 90 be32_to_cpu(sbd->sb_header.mh_format) == GFS_FORMAT_SB) { 91 if (vers == 1) { 92 if (be32_to_cpu(sbd->sb_fs_format) != GFS_FORMAT_FS || 93 be32_to_cpu(sbd->sb_multihost_format) != GFS_FORMAT_MULTI) 94 return -1; /* not gfs1 */ 95 id->type = "gfs"; 96 } 97 else if (vers == 2) { 98 if (be32_to_cpu(sbd->sb_fs_format) != GFS2_FORMAT_FS || 99 be32_to_cpu(sbd->sb_multihost_format) != GFS2_FORMAT_MULTI) 100 return -1; /* not gfs2 */ 101 id->type = "gfs2"; 102 } 103 else 104 return -1; 105 strcpy(id->type_version, "1"); 106 volume_id_set_usage(id, VOLUME_ID_FILESYSTEM); 107 return 0; 108 } 109 return -1; 110} 111 112int volume_id_probe_gfs(struct volume_id *id, uint64_t off, uint64_t size) 113{ 114 return volume_id_probe_gfs_generic(id, off, 1); 115} 116 117int volume_id_probe_gfs2(struct volume_id *id, uint64_t off, uint64_t size) 118{ 119 return volume_id_probe_gfs_generic(id, off, 2); 120} 121