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 * 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 e3fs_mkfs_time; /* when the fs was created */ 127 uint32_t e3fs_jnl_blks[17]; /* backup of the journal inode */ 128 uint32_t e4fs_bcount_hi; /* block count */ 129 uint32_t e4fs_rbcount_hi; /* reserved blocks count */ 130 uint32_t e4fs_fbcount_hi; /* free blocks count */ 131 uint16_t e4fs_min_extra_isize;/* all inodes have at least some bytes */ 132 uint16_t e4fs_want_extra_isize; /* inodes must reserve some bytes */ 133 uint32_t e4fs_flags; /* miscellaneous flags */ 134 uint16_t e4fs_raid_stride; /* RAID stride */ 135 uint16_t e4fs_mmpintv; /* number of seconds to wait in MMP checking */ 136 uint64_t e4fs_mmpblk; /* block for multi-mount protection */ 137 uint32_t e4fs_raid_stripe_wid;/* blocks on all data disks (N * stride) */ 138 uint8_t e4fs_log_gpf; /* FLEX_BG group size */ 139 uint8_t e4fs_char_pad2; 140 uint16_t e4fs_pad; 141 uint32_t reserved2[162]; /* Padding to the end of the block */ 142 }; 143 144 145 /* 146 * In-Memory Superblock 147 */ 148 149 struct m_ext2fs { 150 struct ext2fs * e2fs; 151 char e2fs_fsmnt[MAXMNTLEN];/* name mounted on */ 152 char e2fs_ronly; /* mounted read-only flag */ 153 char e2fs_fmod; /* super block modified flag */ 154 uint32_t e2fs_bsize; /* Block size */ 155 uint32_t e2fs_bshift; /* calc of logical block no */ 156 int32_t e2fs_bmask; /* calc of block offset */ 157 int32_t e2fs_bpg; /* Number of blocks per group */ 158 int64_t e2fs_qbmask; /* = s_blocksize -1 */ 159 uint32_t e2fs_fsbtodb; /* Shift to get disk block */ 160 uint32_t e2fs_ipg; /* Number of inodes per group */ 161 uint32_t e2fs_ipb; /* Number of inodes per block */ 162 uint32_t e2fs_itpg; /* Number of inode table per group */ 163 uint32_t e2fs_fsize; /* Size of fragments per block */ 164 uint32_t e2fs_fpb; /* Number of fragments per block */ 165 uint32_t e2fs_fpg; /* Number of fragments per group */ 166 uint32_t e2fs_dbpg; /* Number of descriptor blocks per group */ 167 uint32_t e2fs_descpb; /* Number of group descriptors per block */ 168 uint32_t e2fs_gdbcount; /* Number of group descriptors */ 169 uint32_t e2fs_gcount; /* Number of groups */ 170 uint32_t e2fs_first_inode;/* First inode on fs */ 171 int32_t e2fs_isize; /* Size of inode */ 172 uint32_t e2fs_mount_opt; 173 uint32_t e2fs_blocksize_bits; 174 uint32_t e2fs_total_dir; /* Total number of directories */ 175 uint8_t *e2fs_contigdirs; /* (u) # of contig. allocated dirs */ 176 char e2fs_wasvalid; /* valid at mount time */ 177 off_t e2fs_maxfilesize; 178 struct ext2_gd *e2fs_gd; /* Group Descriptors */ 179 int32_t e2fs_maxcontig; /* max number of contiguous blks */ 180 int32_t e2fs_contigsumsize; /* size of cluster summary array */ 181 int32_t *e2fs_maxcluster; /* max cluster in each cyl group */ 182 struct csum *e2fs_clustersum; /* cluster summary in each cyl group */ 183 }; 184 185 /* 186 * The second extended file system version 187 */ 188 #define E2FS_DATE "95/08/09" 189 #define E2FS_VERSION "0.5b" 190 191 /* 192 * The second extended file system magic number 193 */ 194 #define E2FS_MAGIC 0xEF53 195 196 /* 197 * Revision levels 198 */ 199 #define E2FS_REV0 0 /* The good old (original) format */ 200 #define E2FS_REV1 1 /* V2 format w/ dynamic inode sizes */ 201 202 #define E2FS_CURRENT_REV E2FS_REV0 203 #define E2FS_MAX_SUPP_REV E2FS_REV1 204 205 #define E2FS_REV0_INODE_SIZE 128 206 207 /* 208 * compatible/incompatible features 209 */ 210 #define EXT2F_COMPAT_PREALLOC 0x0001 211 #define EXT2F_COMPAT_HASJOURNAL 0x0004 212 #define EXT2F_COMPAT_RESIZE 0x0010 213 #define EXT2F_COMPAT_HTREE 0x0020 214 215 #define EXT2F_ROCOMPAT_SPARSESUPER 0x0001 216 #define EXT2F_ROCOMPAT_LARGEFILE 0x0002 217 #define EXT2F_ROCOMPAT_BTREE_DIR 0x0004 218 #define EXT4F_ROCOMPAT_EXTRA_ISIZE 0x0040 219 220 #define EXT2F_INCOMPAT_COMP 0x0001 221 #define EXT2F_INCOMPAT_FTYPE 0x0002 222 223 /* 224 * Features supported in this implementation 225 * 226 * We support the following REV1 features: 227 * - EXT2F_ROCOMPAT_SPARSESUPER 228 * - EXT2F_ROCOMPAT_LARGEFILE 229 * - EXT2F_INCOMPAT_FTYPE 230 */ 231 #define EXT2F_COMPAT_SUPP 0x0000 232 #define EXT2F_ROCOMPAT_SUPP (EXT2F_ROCOMPAT_SPARSESUPER | \ 233 EXT2F_ROCOMPAT_LARGEFILE | \ 234 EXT4F_ROCOMPAT_EXTRA_ISIZE) 235 #define EXT2F_INCOMPAT_SUPP EXT2F_INCOMPAT_FTYPE 236 237 /* Assume that user mode programs are passing in an ext2fs superblock, not 238 * a kernel struct super_block. This will allow us to call the feature-test 239 * macros from user land. */ 240 #define EXT2_SB(sb) (sb) 241 242 /* 243 * Feature set definitions 244 */ 245 #define EXT2_HAS_COMPAT_FEATURE(sb,mask) \ 246 ( EXT2_SB(sb)->e2fs->e2fs_features_compat & htole32(mask) ) 247 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \ 248 ( EXT2_SB(sb)->e2fs->e2fs_features_rocompat & htole32(mask) ) 249 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \ 250 ( EXT2_SB(sb)->e2fs->e2fs_features_incompat & htole32(mask) ) 251 252 /* 253 * Definitions of behavior on errors 254 */ 255 #define E2FS_BEH_CONTINUE 1 /* continue operation */ 256 #define E2FS_BEH_READONLY 2 /* remount fs read only */ 257 #define E2FS_BEH_PANIC 3 /* cause panic */ 258 #define E2FS_BEH_DEFAULT E2FS_BEH_CONTINUE 259 260 /* 261 * OS identification 262 */ 263 #define E2FS_OS_LINUX 0 264 #define E2FS_OS_HURD 1 265 #define E2FS_OS_MASIX 2 266 #define E2FS_OS_FREEBSD 3 267 #define E2FS_OS_LITES 4 268 269 /* 270 * File clean flags 271 */ 272 #define E2FS_ISCLEAN 0x0001 /* Unmounted cleanly */ 273 #define E2FS_ERRORS 0x0002 /* Errors detected */ 274 275 /* ext2 file system block group descriptor */ 276 277 struct ext2_gd { 278 uint32_t ext2bgd_b_bitmap; /* blocks bitmap block */ 279 uint32_t ext2bgd_i_bitmap; /* inodes bitmap block */ 280 uint32_t ext2bgd_i_tables; /* inodes table block */ 281 uint16_t ext2bgd_nbfree; /* number of free blocks */ 282 uint16_t ext2bgd_nifree; /* number of free inodes */ 283 uint16_t ext2bgd_ndirs; /* number of directories */ 284 uint16_t reserved; 285 uint32_t reserved2[3]; 286 }; 287 288 /* cluster summary information */ 289 290 struct csum { 291 int8_t cs_init; /* cluster summary has been initialized */ 292 int32_t *cs_sum; /* cluster summary array */ 293 }; 294 295 /* EXT2FS metadatas are stored in little-endian byte order. These macros 296 * helps reading these metadatas 297 */ 298 299 #define e2fs_cgload(old, new, size) memcpy((new), (old), (size)); 300 #define e2fs_cgsave(old, new, size) memcpy((new), (old), (size)); 301 302 /* 303 * Macro-instructions used to manage several block sizes 304 */ 305 #define EXT2_MIN_BLOCK_SIZE 1024 306 #define EXT2_MAX_BLOCK_SIZE 4096 307 #define EXT2_MIN_BLOCK_LOG_SIZE 10 308 #if defined(_KERNEL) 309 # define EXT2_BLOCK_SIZE(s) ((s)->e2fs_bsize) 310 #else 311 # define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->e2fs_log_bsize) 312 #endif 313 #define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof(uint32_t)) 314 #if defined(_KERNEL) 315 # define EXT2_BLOCK_SIZE_BITS(s) ((s)->e2fs_blocksize_bits) 316 #else 317 # define EXT2_BLOCK_SIZE_BITS(s) ((s)->e2fs_log_bsize + 10) 318 #endif 319 #if defined(_KERNEL) 320 #define EXT2_ADDR_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_addr_per_block_bits) 321 #define EXT2_INODE_SIZE(s) (EXT2_SB(s)->e2fs_isize) 322 #define EXT2_FIRST_INO(s) (EXT2_SB(s)->e2fs_first_inode) 323 #else 324 #define EXT2_INODE_SIZE(s) (((s)->s_rev_level == E2FS_REV0) ? \ 325 E2FS_REV0 : (s)->s_inode_size) 326 #define EXT2_FIRST_INO(s) (((s)->s_rev_level == E2FS_REV0) ? \ 327 E2FS_REV0 : (s)->e2fs_first_ino) 328 #endif 329 330 /* 331 * Macro-instructions used to manage fragments 332 */ 333 #define EXT2_MIN_FRAG_SIZE 1024 334 #define EXT2_MAX_FRAG_SIZE 4096 335 #define EXT2_MIN_FRAG_LOG_SIZE 10 336 #if defined(_KERNEL) 337 # define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->e2fs_fsize) 338 # define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->e2fs_fpb) 339 #else 340 # define EXT2_FRAG_SIZE(s) (EXT2_MIN_FRAG_SIZE << (s)->e2fs_log_fsize) 341 # define EXT2_FRAGS_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s)) 342 #endif 343 344 /* 345 * Macro-instructions used to manage group descriptors 346 */ 347 #if defined(_KERNEL) 348 # define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->e2fs_bpg) 349 # define EXT2_DESC_PER_BLOCK(s) (EXT2_SB(s)->e2fs_descpb) 350 # define EXT2_DESC_PER_BLOCK_BITS(s) (EXT2_SB(s)->s_desc_per_block_bits) 351 #else 352 # define EXT2_BLOCKS_PER_GROUP(s) ((s)->e2fs_bpg) 353 # define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof(struct ext2_gd)) 354 355 #endif 356 357 #endif /* !_FS_EXT2FS_EXT2FS_H_ */ 358