1 /*- 2 * modified for EXT2FS support in Lites 1.1 3 * 4 * Aug 1995, Godmar Back (gback@cs.utah.edu) 5 * University of Utah, Department of Computer Science 6 * 7 * $FreeBSD$ 8 */ 9 /*- 10 * Copyright (c) 2009 Aditya Sarawgi 11 * All rights reserved. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * 35 */ 36 37 #ifndef _FS_EXT2FS_EXT2FS_H_ 38 #define _FS_EXT2FS_EXT2FS_H_ 39 40 #include <sys/types.h> 41 42 /* 43 * Maximal count of links to a file 44 */ 45 #define EXT2_LINK_MAX 32000 46 47 /* 48 * The path name on which the file system is mounted is maintained 49 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in 50 * the super block for this name. 51 */ 52 #define MAXMNTLEN 512 53 54 /* 55 * Super block for an ext2fs file system. 56 */ 57 struct ext2fs { 58 uint32_t e2fs_icount; /* Inode count */ 59 uint32_t e2fs_bcount; /* blocks count */ 60 uint32_t e2fs_rbcount; /* reserved blocks count */ 61 uint32_t e2fs_fbcount; /* free blocks count */ 62 uint32_t e2fs_ficount; /* free inodes count */ 63 uint32_t e2fs_first_dblock; /* first data block */ 64 uint32_t e2fs_log_bsize; /* block size = 1024*(2^e2fs_log_bsize) */ 65 uint32_t e2fs_log_fsize; /* fragment size */ 66 uint32_t e2fs_bpg; /* blocks per group */ 67 uint32_t e2fs_fpg; /* frags per group */ 68 uint32_t e2fs_ipg; /* inodes per group */ 69 uint32_t e2fs_mtime; /* mount time */ 70 uint32_t e2fs_wtime; /* write time */ 71 uint16_t e2fs_mnt_count; /* mount count */ 72 uint16_t e2fs_max_mnt_count; /* max mount count */ 73 uint16_t e2fs_magic; /* magic number */ 74 uint16_t e2fs_state; /* file system state */ 75 uint16_t e2fs_beh; /* behavior on errors */ 76 uint16_t e2fs_minrev; /* minor revision level */ 77 uint32_t e2fs_lastfsck; /* time of last fsck */ 78 uint32_t e2fs_fsckintv; /* max time between fscks */ 79 uint32_t e2fs_creator; /* creator OS */ 80 uint32_t e2fs_rev; /* revision level */ 81 uint16_t e2fs_ruid; /* default uid for reserved blocks */ 82 uint16_t e2fs_rgid; /* default gid for reserved blocks */ 83 /* EXT2_DYNAMIC_REV superblocks */ 84 uint32_t e2fs_first_ino; /* first non-reserved inode */ 85 uint16_t e2fs_inode_size; /* size of inode structure */ 86 uint16_t e2fs_block_group_nr; /* block grp number of this sblk*/ 87 uint32_t e2fs_features_compat; /* compatible feature set */ 88 uint32_t e2fs_features_incompat; /* incompatible feature set */ 89 uint32_t e2fs_features_rocompat; /* RO-compatible feature set */ 90 uint8_t e2fs_uuid[16]; /* 128-bit uuid for volume */ 91 char e2fs_vname[16]; /* volume name */ 92 char e2fs_fsmnt[64]; /* name mounted on */ 93 uint32_t e2fs_algo; /* For compression */ 94 uint8_t e2fs_prealloc; /* # of blocks for old prealloc */ 95 uint8_t e2fs_dir_prealloc; /* # of blocks for old prealloc dirs */ 96 uint16_t e2fs_reserved_ngdb; /* # of reserved gd blocks for resize */ 97 char e3fs_journal_uuid[16]; /* uuid of journal superblock */ 98 uint32_t e3fs_journal_inum; /* inode number of journal file */ 99 uint32_t e3fs_journal_dev; /* device number of journal file */ 100 uint32_t e3fs_last_orphan; /* start of list of inodes to delete */ 101 uint32_t e3fs_hash_seed[4]; /* HTREE hash seed */ 102 char e3fs_def_hash_version; /* Default hash version to use */ 103 char e3fs_reserved_char_pad; 104 uint32_t e3fs_default_mount_opts; 105 uint32_t e3fs_first_meta_bg; /* First metablock block group */ 106 uint32_t e3fs_mkfs_time; /* when the fs was created */ 107 uint32_t e3fs_jnl_blks[17]; /* backup of the journal inode */ 108 uint32_t e4fs_bcount_hi; /* block count */ 109 uint32_t e4fs_rbcount_hi; /* reserved blocks count */ 110 uint32_t e4fs_fbcount_hi; /* free blocks count */ 111 uint16_t e4fs_min_extra_isize;/* all inodes have at least some bytes */ 112 uint16_t e4fs_want_extra_isize; /* inodes must reserve some bytes */ 113 uint32_t e4fs_flags; /* miscellaneous flags */ 114 uint16_t e4fs_raid_stride; /* RAID stride */ 115 uint16_t e4fs_mmpintv; /* number of seconds to wait in MMP checking */ 116 uint64_t e4fs_mmpblk; /* block for multi-mount protection */ 117 uint32_t e4fs_raid_stripe_wid;/* blocks on all data disks (N * stride) */ 118 uint8_t e4fs_log_gpf; /* FLEX_BG group size */ 119 uint8_t e4fs_char_pad2; 120 uint16_t e4fs_pad; 121 uint32_t reserved2[162]; /* Padding to the end of the block */ 122 }; 123 124 125 /* 126 * In-Memory Superblock 127 */ 128 129 struct m_ext2fs { 130 struct ext2fs * e2fs; 131 char e2fs_fsmnt[MAXMNTLEN];/* name mounted on */ 132 char e2fs_ronly; /* mounted read-only flag */ 133 char e2fs_fmod; /* super block modified flag */ 134 uint32_t e2fs_bsize; /* Block size */ 135 uint32_t e2fs_bshift; /* calc of logical block no */ 136 uint32_t e2fs_bpg; /* Number of blocks per group */ 137 int64_t e2fs_qbmask; /* = s_blocksize -1 */ 138 uint32_t e2fs_fsbtodb; /* Shift to get disk block */ 139 uint32_t e2fs_ipg; /* Number of inodes per group */ 140 uint32_t e2fs_ipb; /* Number of inodes per block */ 141 uint32_t e2fs_itpg; /* Number of inode table per group */ 142 uint32_t e2fs_fsize; /* Size of fragments per block */ 143 uint32_t e2fs_fpb; /* Number of fragments per block */ 144 uint32_t e2fs_fpg; /* Number of fragments per group */ 145 uint32_t e2fs_gdbcount; /* Number of group descriptors */ 146 uint32_t e2fs_gcount; /* Number of groups */ 147 uint32_t e2fs_isize; /* Size of inode */ 148 uint32_t e2fs_total_dir; /* Total number of directories */ 149 uint8_t *e2fs_contigdirs; /* (u) # of contig. allocated dirs */ 150 char e2fs_wasvalid; /* valid at mount time */ 151 off_t e2fs_maxfilesize; 152 struct ext2_gd *e2fs_gd; /* Group Descriptors */ 153 int32_t e2fs_contigsumsize; /* size of cluster summary array */ 154 int32_t *e2fs_maxcluster; /* max cluster in each cyl group */ 155 struct csum *e2fs_clustersum; /* cluster summary in each cyl group */ 156 }; 157 158 /* cluster summary information */ 159 160 struct csum { 161 int8_t cs_init; /* cluster summary has been initialized */ 162 int32_t *cs_sum; /* cluster summary array */ 163 }; 164 165 /* 166 * The second extended file system magic number 167 */ 168 #define E2FS_MAGIC 0xEF53 169 170 /* 171 * Revision levels 172 */ 173 #define E2FS_REV0 0 /* The good old (original) format */ 174 #define E2FS_REV1 1 /* V2 format w/ dynamic inode sizes */ 175 176 #define E2FS_REV0_INODE_SIZE 128 177 178 /* 179 * compatible/incompatible features 180 */ 181 #define EXT2F_COMPAT_PREALLOC 0x0001 182 #define EXT2F_COMPAT_HASJOURNAL 0x0004 183 #define EXT2F_COMPAT_RESIZE 0x0010 184 #define EXT2F_COMPAT_DIRHASHINDEX 0x0020 185 186 #define EXT2F_ROCOMPAT_SPARSESUPER 0x0001 187 #define EXT2F_ROCOMPAT_LARGEFILE 0x0002 188 #define EXT2F_ROCOMPAT_BTREE_DIR 0x0004 189 #define EXT2F_ROCOMPAT_HUGE_FILE 0x0008 190 #define EXT2F_ROCOMPAT_GDT_CSUM 0x0010 191 #define EXT2F_ROCOMPAT_DIR_NLINK 0x0020 192 #define EXT2F_ROCOMPAT_EXTRA_ISIZE 0x0040 193 194 #define EXT2F_INCOMPAT_COMP 0x0001 195 #define EXT2F_INCOMPAT_FTYPE 0x0002 196 #define EXT2F_INCOMPAT_META_BG 0x0010 197 #define EXT2F_INCOMPAT_EXTENTS 0x0040 198 #define EXT2F_INCOMPAT_64BIT 0x0080 199 #define EXT2F_INCOMPAT_MMP 0x0100 200 #define EXT2F_INCOMPAT_FLEX_BG 0x0200 201 202 /* 203 * Features supported in this implementation 204 * 205 * We support the following REV1 features: 206 * - EXT2F_ROCOMPAT_SPARSESUPER 207 * - EXT2F_ROCOMPAT_LARGEFILE 208 * - EXT2F_INCOMPAT_FTYPE 209 */ 210 #define EXT2F_COMPAT_SUPP 0x0000 211 #define EXT2F_ROCOMPAT_SUPP (EXT2F_ROCOMPAT_SPARSESUPER | \ 212 EXT2F_ROCOMPAT_LARGEFILE | \ 213 EXT2F_ROCOMPAT_EXTRA_ISIZE) 214 #define EXT2F_INCOMPAT_SUPP EXT2F_INCOMPAT_FTYPE 215 216 /* Assume that user mode programs are passing in an ext2fs superblock, not 217 * a kernel struct super_block. This will allow us to call the feature-test 218 * macros from user land. */ 219 #define EXT2_SB(sb) (sb) 220 221 /* 222 * Feature set definitions 223 */ 224 #define EXT2_HAS_COMPAT_FEATURE(sb,mask) \ 225 ( EXT2_SB(sb)->e2fs->e2fs_features_compat & htole32(mask) ) 226 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \ 227 ( EXT2_SB(sb)->e2fs->e2fs_features_rocompat & htole32(mask) ) 228 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \ 229 ( EXT2_SB(sb)->e2fs->e2fs_features_incompat & htole32(mask) ) 230 231 /* 232 * File clean flags 233 */ 234 #define E2FS_ISCLEAN 0x0001 /* Unmounted cleanly */ 235 #define E2FS_ERRORS 0x0002 /* Errors detected */ 236 237 /* ext2 file system block group descriptor */ 238 239 struct ext2_gd { 240 uint32_t ext2bgd_b_bitmap; /* blocks bitmap block */ 241 uint32_t ext2bgd_i_bitmap; /* inodes bitmap block */ 242 uint32_t ext2bgd_i_tables; /* inodes table block */ 243 uint16_t ext2bgd_nbfree; /* number of free blocks */ 244 uint16_t ext2bgd_nifree; /* number of free inodes */ 245 uint16_t ext2bgd_ndirs; /* number of directories */ 246 uint16_t ext2bgd_flags; /* block group flags */ 247 uint32_t ext2bgd_x_bitmap; /* snapshot exclusion bitmap loc. */ 248 uint16_t ext2bgd_b_bmap_csum; /* block bitmap checksum */ 249 uint16_t ext2bgd_i_bmap_csum; /* inode bitmap checksum */ 250 uint16_t ext2bgd_i_unused; /* unused inode count */ 251 uint16_t ext2bgd_csum; /* group descriptor checksum */ 252 }; 253 254 255 /* EXT2FS metadatas are stored in little-endian byte order. These macros 256 * helps reading these metadatas 257 */ 258 259 #define e2fs_cgload(old, new, size) memcpy((new), (old), (size)); 260 #define e2fs_cgsave(old, new, size) memcpy((new), (old), (size)); 261 262 /* 263 * Macro-instructions used to manage several block sizes 264 */ 265 #define EXT2_MAX_BLOCK_SIZE 4096 266 #define EXT2_MIN_BLOCK_LOG_SIZE 10 267 #define EXT2_BLOCK_SIZE(s) ((s)->e2fs_bsize) 268 #define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof(uint32_t)) 269 #define EXT2_INODE_SIZE(s) (EXT2_SB(s)->e2fs_isize) 270 271 /* 272 * Macro-instructions used to manage fragments 273 */ 274 #define EXT2_MIN_FRAG_SIZE 1024 275 #define EXT2_MAX_FRAG_SIZE 4096 276 #define EXT2_MIN_FRAG_LOG_SIZE 10 277 #define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->e2fs_fsize) 278 #define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->e2fs_fpb) 279 280 /* 281 * Macro-instructions used to manage group descriptors 282 */ 283 #define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->e2fs_bpg) 284 285 #endif /* !_FS_EXT2FS_EXT2FS_H_ */ 286