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_EXT2_FS_H_ 38 #define _FS_EXT2FS_EXT2_FS_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 * A summary of contiguous blocks of various sizes is maintained 49 * in each cylinder group. Normally this is set by the initial 50 * value of fs_maxcontig. 51 * 52 * XXX:FS_MAXCONTIG is set to 16 to conserve space. Here we set 53 * EXT2_MAXCONTIG to 32 for better performance. 54 */ 55 #define EXT2_MAXCONTIG 32 56 57 /* 58 * Constants relative to the data blocks 59 */ 60 #define EXT2_NDIR_BLOCKS 12 61 #define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS 62 #define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1) 63 #define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1) 64 #define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1) 65 #define EXT2_MAXSYMLINKLEN (EXT2_N_BLOCKS * sizeof (uint32_t)) 66 67 /* 68 * The path name on which the file system is mounted is maintained 69 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in 70 * the super block for this name. 71 */ 72 #define MAXMNTLEN 512 73 74 /* 75 * Super block for an ext2fs file system. 76 */ 77 struct ext2fs { 78 uint32_t e2fs_icount; /* Inode count */ 79 uint32_t e2fs_bcount; /* blocks count */ 80 uint32_t e2fs_rbcount; /* reserved blocks count */ 81 uint32_t e2fs_fbcount; /* free blocks count */ 82 uint32_t e2fs_ficount; /* free inodes count */ 83 uint32_t e2fs_first_dblock; /* first data block */ 84 uint32_t e2fs_log_bsize; /* block size = 1024*(2^e2fs_log_bsize) */ 85 uint32_t e2fs_log_fsize; /* fragment size */ 86 uint32_t e2fs_bpg; /* blocks per group */ 87 uint32_t e2fs_fpg; /* frags per group */ 88 uint32_t e2fs_ipg; /* inodes per group */ 89 uint32_t e2fs_mtime; /* mount time */ 90 uint32_t e2fs_wtime; /* write time */ 91 uint16_t e2fs_mnt_count; /* mount count */ 92 uint16_t e2fs_max_mnt_count; /* max mount count */ 93 uint16_t e2fs_magic; /* magic number */ 94 uint16_t e2fs_state; /* file system state */ 95 uint16_t e2fs_beh; /* behavior on errors */ 96 uint16_t e2fs_minrev; /* minor revision level */ 97 uint32_t e2fs_lastfsck; /* time of last fsck */ 98 uint32_t e2fs_fsckintv; /* max time between fscks */ 99 uint32_t e2fs_creator; /* creator OS */ 100 uint32_t e2fs_rev; /* revision level */ 101 uint16_t e2fs_ruid; /* default uid for reserved blocks */ 102 uint16_t e2fs_rgid; /* default gid for reserved blocks */ 103 /* EXT2_DYNAMIC_REV superblocks */ 104 uint32_t e2fs_first_ino; /* first non-reserved inode */ 105 uint16_t e2fs_inode_size; /* size of inode structure */ 106 uint16_t e2fs_block_group_nr; /* block grp number of this sblk*/ 107 uint32_t e2fs_features_compat; /* compatible feature set */ 108 uint32_t e2fs_features_incompat; /* incompatible feature set */ 109 uint32_t e2fs_features_rocompat; /* RO-compatible feature set */ 110 uint8_t e2fs_uuid[16]; /* 128-bit uuid for volume */ 111 char e2fs_vname[16]; /* volume name */ 112 char e2fs_fsmnt[64]; /* name mounted on */ 113 uint32_t e2fs_algo; /* For compression */ 114 uint8_t e2fs_prealloc; /* # of blocks for old prealloc */ 115 uint8_t e2fs_dir_prealloc; /* # of blocks for old prealloc dirs */ 116 uint16_t e2fs_reserved_ngdb; /* # of reserved gd blocks for resize */ 117 char e3fs_journal_uuid[16]; /* uuid of journal superblock */ 118 uint32_t e3fs_journal_inum; /* inode number of journal file */ 119 uint32_t e3fs_journal_dev; /* device number of journal file */ 120 uint32_t e3fs_last_orphan; /* start of list of inodes to delete */ 121 uint32_t e3fs_hash_seed[4]; /* HTREE hash seed */ 122 char e3fs_def_hash_version; /* Default hash version to use */ 123 char e3fs_reserved_char_pad; 124 uint32_t e3fs_default_mount_opts; 125 uint32_t e3fs_first_meta_bg; /* First metablock block group */ 126 uint32_t reserved2[190]; /* Padding to the end of the block */ 127 }; 128 129 130 /* 131 * In-Memory Superblock 132 */ 133 134 struct m_ext2fs { 135 struct ext2fs * e2fs; 136 char e2fs_fsmnt[MAXMNTLEN];/* name mounted on */ 137 char e2fs_ronly; /* mounted read-only flag */ 138 char e2fs_fmod; /* super block modified flag */ 139 uint32_t e2fs_bsize; /* Block size */ 140 uint32_t e2fs_bshift; /* calc of logical block no */ 141 int32_t e2fs_bmask; /* calc of block offset */ 142 int32_t e2fs_bpg; /* Number of blocks per group */ 143 int64_t e2fs_qbmask; /* = s_blocksize -1 */ 144 uint32_t e2fs_fsbtodb; /* Shift to get disk block */ 145 uint32_t e2fs_ipg; /* Number of inodes per group */ 146 uint32_t e2fs_ipb; /* Number of inodes per block */ 147 uint32_t e2fs_itpg; /* Number of inode table per group */ 148 uint32_t e2fs_fsize; /* Size of fragments per block */ 149 uint32_t e2fs_fpb; /* Number of fragments per block */ 150 uint32_t e2fs_fpg; /* Number of fragments per group */ 151 uint32_t e2fs_dbpg; /* Number of descriptor blocks per group */ 152 uint32_t e2fs_descpb; /* Number of group descriptors per block */ 153 uint32_t e2fs_gdbcount; /* Number of group descriptors */ 154 uint32_t e2fs_gcount; /* Number of groups */ 155 uint32_t e2fs_first_inode;/* First inode on fs */ 156 int32_t e2fs_isize; /* Size of inode */ 157 uint32_t e2fs_mount_opt; 158 uint32_t e2fs_blocksize_bits; 159 uint32_t e2fs_total_dir; /* Total number of directories */ 160 uint8_t *e2fs_contigdirs; /* (u) # of contig. allocated dirs */ 161 char e2fs_wasvalid; /* valid at mount time */ 162 off_t e2fs_maxfilesize; 163 struct ext2_gd *e2fs_gd; /* Group Descriptors */ 164 int32_t e2fs_maxcontig; /* max number of contiguous blks */ 165 int32_t e2fs_contigsumsize; /* size of cluster summary array */ 166 int32_t *e2fs_maxcluster; /* max cluster in each cyl group */ 167 struct csum *e2fs_clustersum; /* cluster summary in each cyl group */ 168 }; 169 170 /* 171 * The second extended file system version 172 */ 173 #define E2FS_DATE "95/08/09" 174 #define E2FS_VERSION "0.5b" 175 176 /* 177 * The second extended file system magic number 178 */ 179 #define E2FS_MAGIC 0xEF53 180 181 /* 182 * Revision levels 183 */ 184 #define E2FS_REV0 0 /* The good old (original) format */ 185 #define E2FS_REV1 1 /* V2 format w/ dynamic inode sizes */ 186 187 #define E2FS_CURRENT_REV E2FS_REV0 188 #define E2FS_MAX_SUPP_REV E2FS_REV1 189 190 #define E2FS_REV0_INODE_SIZE 128 191 192 /* 193 * compatible/incompatible features 194 */ 195 #define EXT2F_COMPAT_PREALLOC 0x0001 196 #define EXT2F_COMPAT_HASJOURNAL 0x0004 197 #define EXT2F_COMPAT_RESIZE 0x0010 198 199 #define EXT2F_ROCOMPAT_SPARSESUPER 0x0001 200 #define EXT2F_ROCOMPAT_LARGEFILE 0x0002 201 #define EXT2F_ROCOMPAT_BTREE_DIR 0x0004 202 203 #define EXT2F_INCOMPAT_COMP 0x0001 204 #define EXT2F_INCOMPAT_FTYPE 0x0002 205 206 /* 207 * Features supported in this implementation 208 * 209 * We support the following REV1 features: 210 * - EXT2F_ROCOMPAT_SPARSESUPER 211 * - EXT2F_ROCOMPAT_LARGEFILE 212 * - EXT2F_INCOMPAT_FTYPE 213 */ 214 #define EXT2F_COMPAT_SUPP 0x0000 215 #define EXT2F_ROCOMPAT_SUPP (EXT2F_ROCOMPAT_SPARSESUPER \ 216 | EXT2F_ROCOMPAT_LARGEFILE) 217 #define EXT2F_INCOMPAT_SUPP EXT2F_INCOMPAT_FTYPE 218 219 /* Assume that user mode programs are passing in an ext2fs superblock, not 220 * a kernel struct super_block. This will allow us to call the feature-test 221 * macros from user land. */ 222 #define EXT2_SB(sb) (sb) 223 224 /* 225 * Feature set definitions 226 */ 227 #define EXT2_HAS_COMPAT_FEATURE(sb,mask) \ 228 ( EXT2_SB(sb)->e2fs->e2fs_features_compat & htole32(mask) ) 229 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \ 230 ( EXT2_SB(sb)->e2fs->e2fs_features_rocompat & htole32(mask) ) 231 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \ 232 ( EXT2_SB(sb)->e2fs->e2fs_features_incompat & htole32(mask) ) 233 234 /* 235 * Definitions of behavior on errors 236 */ 237 #define E2FS_BEH_CONTINUE 1 /* continue operation */ 238 #define E2FS_BEH_READONLY 2 /* remount fs read only */ 239 #define E2FS_BEH_PANIC 3 /* cause panic */ 240 #define E2FS_BEH_DEFAULT E2FS_BEH_CONTINUE 241 242 /* 243 * OS identification 244 */ 245 #define E2FS_OS_LINUX 0 246 #define E2FS_OS_HURD 1 247 #define E2FS_OS_MASIX 2 248 #define E2FS_OS_FREEBSD 3 249 #define E2FS_OS_LITES 4 250 251 /* 252 * File clean flags 253 */ 254 #define E2FS_ISCLEAN 0x0001 /* Unmounted cleanly */ 255 #define E2FS_ERRORS 0x0002 /* Errors detected */ 256 257 /* ext2 file system block group descriptor */ 258 259 struct ext2_gd { 260 uint32_t ext2bgd_b_bitmap; /* blocks bitmap block */ 261 uint32_t ext2bgd_i_bitmap; /* inodes bitmap block */ 262 uint32_t ext2bgd_i_tables; /* inodes table block */ 263 uint16_t ext2bgd_nbfree; /* number of free blocks */ 264 uint16_t ext2bgd_nifree; /* number of free inodes */ 265 uint16_t ext2bgd_ndirs; /* number of directories */ 266 uint16_t reserved; 267 uint32_t reserved2[3]; 268 }; 269 270 /* cluster summary information */ 271 272 struct csum { 273 int8_t cs_init; /* cluster summary has been initialized */ 274 int32_t *cs_sum; /* cluster summary array */ 275 }; 276 277 /* EXT2FS metadatas are stored in little-endian byte order. These macros 278 * helps reading these metadatas 279 */ 280 281 #define e2fs_cgload(old, new, size) memcpy((new), (old), (size)); 282 #define e2fs_cgsave(old, new, size) memcpy((new), (old), (size)); 283 284 /* 285 * Macro-instructions used to manage several block sizes 286 */ 287 #define EXT2_MIN_BLOCK_SIZE 1024 288 #define EXT2_MAX_BLOCK_SIZE 4096 289 #define EXT2_MIN_BLOCK_LOG_SIZE 10 290 #if defined(_KERNEL) 291 # define EXT2_BLOCK_SIZE(s) ((s)->e2fs_bsize) 292 #else 293 # define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->e2fs_log_bsize) 294 #endif 295 #define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (uint32_t)) 296 #if defined(_KERNEL) 297 # define EXT2_BLOCK_SIZE_BITS(s) ((s)->e2fs_blocksize_bits) 298 #else 299 # define EXT2_BLOCK_SIZE_BITS(s) ((s)->e2fs_log_bsize + 10) 300 #endif 301 #if defined(_KERNEL) 302 #define EXT2_ADDR_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_addr_per_block_bits) 303 #define EXT2_INODE_SIZE(s) (EXT2_SB(s)->e2fs_isize) 304 #define EXT2_FIRST_INO(s) (EXT2_SB(s)->e2fs_first_inode) 305 #else 306 #define EXT2_INODE_SIZE(s) (((s)->s_rev_level == E2FS_REV0) ? \ 307 E2FS_REV0 : (s)->s_inode_size) 308 #define EXT2_FIRST_INO(s) (((s)->s_rev_level == E2FS_REV0) ? \ 309 E2FS_REV0 : (s)->e2fs_first_ino) 310 #endif 311 312 /* 313 * Macro-instructions used to manage fragments 314 */ 315 #define EXT2_MIN_FRAG_SIZE 1024 316 #define EXT2_MAX_FRAG_SIZE 4096 317 #define EXT2_MIN_FRAG_LOG_SIZE 10 318 #if defined(_KERNEL) 319 # define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->e2fs_fsize) 320 # define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->e2fs_fpb) 321 #else 322 # define EXT2_FRAG_SIZE(s) (EXT2_MIN_FRAG_SIZE << (s)->e2fs_log_fsize) 323 # define EXT2_FRAGS_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s)) 324 #endif 325 326 /* 327 * Macro-instructions used to manage group descriptors 328 */ 329 #if defined(_KERNEL) 330 # define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->e2fs_bpg) 331 # define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->e2fs_descpb) 332 # define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits) 333 #else 334 # define EXT2_BLOCKS_PER_GROUP(s) ((s)->e2fs_bpg) 335 # define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_gd)) 336 337 #endif 338 339 #endif /* !_FS_EXT2FS_EXT2FS_H_ */ 340