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 /*- 8 * SPDX-License-Identifier: BSD-2-Clause 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 * Super block for an ext2fs file system. 44 */ 45 struct ext2fs { 46 uint32_t e2fs_icount; /* Inode count */ 47 uint32_t e2fs_bcount; /* blocks count */ 48 uint32_t e2fs_rbcount; /* reserved blocks count */ 49 uint32_t e2fs_fbcount; /* free blocks count */ 50 uint32_t e2fs_ficount; /* free inodes count */ 51 uint32_t e2fs_first_dblock; /* first data block */ 52 uint32_t e2fs_log_bsize; /* block size = 1024*(2^e2fs_log_bsize) */ 53 uint32_t e2fs_log_fsize; /* fragment size */ 54 uint32_t e2fs_bpg; /* blocks per group */ 55 uint32_t e2fs_fpg; /* frags per group */ 56 uint32_t e2fs_ipg; /* inodes per group */ 57 uint32_t e2fs_mtime; /* mount time */ 58 uint32_t e2fs_wtime; /* write time */ 59 uint16_t e2fs_mnt_count; /* mount count */ 60 uint16_t e2fs_max_mnt_count; /* max mount count */ 61 uint16_t e2fs_magic; /* magic number */ 62 uint16_t e2fs_state; /* file system state */ 63 uint16_t e2fs_beh; /* behavior on errors */ 64 uint16_t e2fs_minrev; /* minor revision level */ 65 uint32_t e2fs_lastfsck; /* time of last fsck */ 66 uint32_t e2fs_fsckintv; /* max time between fscks */ 67 uint32_t e2fs_creator; /* creator OS */ 68 uint32_t e2fs_rev; /* revision level */ 69 uint16_t e2fs_ruid; /* default uid for reserved blocks */ 70 uint16_t e2fs_rgid; /* default gid for reserved blocks */ 71 /* EXT2_DYNAMIC_REV superblocks */ 72 uint32_t e2fs_first_ino; /* first non-reserved inode */ 73 uint16_t e2fs_inode_size; /* size of inode structure */ 74 uint16_t e2fs_block_group_nr; /* block grp number of this sblk*/ 75 uint32_t e2fs_features_compat; /* compatible feature set */ 76 uint32_t e2fs_features_incompat; /* incompatible feature set */ 77 uint32_t e2fs_features_rocompat; /* RO-compatible feature set */ 78 uint8_t e2fs_uuid[16]; /* 128-bit uuid for volume */ 79 char e2fs_vname[16]; /* volume name */ 80 char e2fs_fsmnt[64]; /* name mounted on */ 81 uint32_t e2fs_algo; /* For compression */ 82 uint8_t e2fs_prealloc; /* # of blocks for old prealloc */ 83 uint8_t e2fs_dir_prealloc; /* # of blocks for old prealloc dirs */ 84 uint16_t e2fs_reserved_ngdb; /* # of reserved gd blocks for resize */ 85 char e3fs_journal_uuid[16]; /* uuid of journal superblock */ 86 uint32_t e3fs_journal_inum; /* inode number of journal file */ 87 uint32_t e3fs_journal_dev; /* device number of journal file */ 88 uint32_t e3fs_last_orphan; /* start of list of inodes to delete */ 89 uint32_t e3fs_hash_seed[4]; /* HTREE hash seed */ 90 char e3fs_def_hash_version;/* Default hash version to use */ 91 char e3fs_jnl_backup_type; 92 uint16_t e3fs_desc_size; /* size of group descriptor */ 93 uint32_t e3fs_default_mount_opts; 94 uint32_t e3fs_first_meta_bg; /* First metablock block group */ 95 uint32_t e3fs_mkfs_time; /* when the fs was created */ 96 uint32_t e3fs_jnl_blks[17]; /* backup of the journal inode */ 97 uint32_t e4fs_bcount_hi; /* high bits of blocks count */ 98 uint32_t e4fs_rbcount_hi; /* high bits of reserved blocks count */ 99 uint32_t e4fs_fbcount_hi; /* high bits of free blocks count */ 100 uint16_t e4fs_min_extra_isize; /* all inodes have some bytes */ 101 uint16_t e4fs_want_extra_isize;/* inodes must reserve some bytes */ 102 uint32_t e4fs_flags; /* miscellaneous flags */ 103 uint16_t e4fs_raid_stride; /* RAID stride */ 104 uint16_t e4fs_mmpintv; /* seconds to wait in MMP checking */ 105 uint64_t e4fs_mmpblk; /* block for multi-mount protection */ 106 uint32_t e4fs_raid_stripe_wid; /* blocks on data disks (N * stride) */ 107 uint8_t e4fs_log_gpf; /* FLEX_BG group size */ 108 uint8_t e4fs_chksum_type; /* metadata checksum algorithm used */ 109 uint8_t e4fs_encrypt; /* versioning level for encryption */ 110 uint8_t e4fs_reserved_pad; 111 uint64_t e4fs_kbytes_written; /* number of lifetime kilobytes */ 112 uint32_t e4fs_snapinum; /* inode number of active snapshot */ 113 uint32_t e4fs_snapid; /* sequential ID of active snapshot */ 114 uint64_t e4fs_snaprbcount; /* reserved blocks for active snapshot */ 115 uint32_t e4fs_snaplist; /* inode number for on-disk snapshot */ 116 uint32_t e4fs_errcount; /* number of file system errors */ 117 uint32_t e4fs_first_errtime; /* first time an error happened */ 118 uint32_t e4fs_first_errino; /* inode involved in first error */ 119 uint64_t e4fs_first_errblk; /* block involved of first error */ 120 uint8_t e4fs_first_errfunc[32];/* function where error happened */ 121 uint32_t e4fs_first_errline; /* line number where error happened */ 122 uint32_t e4fs_last_errtime; /* most recent time of an error */ 123 uint32_t e4fs_last_errino; /* inode involved in last error */ 124 uint32_t e4fs_last_errline; /* line number where error happened */ 125 uint64_t e4fs_last_errblk; /* block involved of last error */ 126 uint8_t e4fs_last_errfunc[32]; /* function where error happened */ 127 uint8_t e4fs_mount_opts[64]; 128 uint32_t e4fs_usrquota_inum; /* inode for tracking user quota */ 129 uint32_t e4fs_grpquota_inum; /* inode for tracking group quota */ 130 uint32_t e4fs_overhead_clusters;/* overhead blocks/clusters */ 131 uint32_t e4fs_backup_bgs[2]; /* groups with sparse_super2 SBs */ 132 uint8_t e4fs_encrypt_algos[4];/* encryption algorithms in use */ 133 uint8_t e4fs_encrypt_pw_salt[16];/* salt used for string2key */ 134 uint32_t e4fs_lpf_ino; /* location of the lost+found inode */ 135 uint32_t e4fs_proj_quota_inum; /* inode for tracking project quota */ 136 uint32_t e4fs_chksum_seed; /* checksum seed */ 137 uint32_t e4fs_reserved[98]; /* padding to the end of the block */ 138 uint32_t e4fs_sbchksum; /* superblock checksum */ 139 }; 140 141 /* 142 * The path name on which the file system is mounted is maintained 143 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in 144 * the super block for this name. 145 */ 146 #define MAXMNTLEN 512 147 148 /* 149 * In-Memory Superblock 150 */ 151 152 struct m_ext2fs { 153 struct ext2fs * e2fs; 154 char e2fs_fsmnt[MAXMNTLEN];/* name mounted on */ 155 char e2fs_ronly; /* mounted read-only flag */ 156 char e2fs_fmod; /* super block modified flag */ 157 uint64_t e2fs_bcount; /* blocks count */ 158 uint64_t e2fs_rbcount; /* reserved blocks count */ 159 uint64_t e2fs_fbcount; /* free blocks count */ 160 uint32_t e2fs_ficount; /* free inodes count */ 161 uint32_t e2fs_bsize; /* Block size */ 162 uint32_t e2fs_bshift; /* calc of logical block no */ 163 uint32_t e2fs_bpg; /* Number of blocks per group */ 164 int64_t e2fs_qbmask; /* = s_blocksize -1 */ 165 uint32_t e2fs_fsbtodb; /* Shift to get disk block */ 166 uint32_t e2fs_ipg; /* Number of inodes per group */ 167 uint32_t e2fs_ipb; /* Number of inodes per block */ 168 uint32_t e2fs_itpg; /* Number of inode table per group */ 169 uint32_t e2fs_fsize; /* Size of fragments per block */ 170 uint32_t e2fs_fpb; /* Number of fragments per block */ 171 uint32_t e2fs_fpg; /* Number of fragments per group */ 172 uint32_t e2fs_gdbcount; /* Number of group descriptors */ 173 uint32_t e2fs_gcount; /* Number of groups */ 174 uint32_t e2fs_isize; /* Size of inode */ 175 uint32_t e2fs_total_dir; /* Total number of directories */ 176 uint8_t *e2fs_contigdirs; /* (u) # of contig. allocated dirs */ 177 char e2fs_wasvalid; /* valid at mount time */ 178 off_t e2fs_maxfilesize; 179 struct ext2_gd *e2fs_gd; /* Group Descriptors */ 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 int32_t e2fs_uhash; /* 3 if hash should be signed, 0 if not */ 184 uint32_t e2fs_csum_seed; /* sb checksum seed */ 185 uint64_t e2fs_maxsymlinklen; /* max size of short symlink */ 186 }; 187 188 /* cluster summary information */ 189 190 struct csum { 191 int8_t cs_init; /* cluster summary has been initialized */ 192 int32_t *cs_sum; /* cluster summary array */ 193 }; 194 195 /* 196 * The second extended file system magic number 197 */ 198 #define E2FS_MAGIC 0xEF53 199 200 /* 201 * Revision levels 202 */ 203 #define E2FS_REV0 0 /* The good old (original) format */ 204 #define E2FS_REV1 1 /* V2 format w/ dynamic inode sizes */ 205 206 #define E2FS_REV0_INODE_SIZE 128 207 208 /* 209 * Metadata checksum algorithm codes 210 */ 211 #define EXT4_CRC32C_CHKSUM 1 212 213 /* 214 * compatible/incompatible features 215 */ 216 #define EXT2F_COMPAT_PREALLOC 0x0001 217 #define EXT2F_COMPAT_IMAGIC_INODES 0x0002 218 #define EXT2F_COMPAT_HASJOURNAL 0x0004 219 #define EXT2F_COMPAT_EXT_ATTR 0x0008 220 #define EXT2F_COMPAT_RESIZE 0x0010 221 #define EXT2F_COMPAT_DIRHASHINDEX 0x0020 222 #define EXT2F_COMPAT_LAZY_BG 0x0040 223 #define EXT2F_COMPAT_EXCLUDE_BITMAP 0x0100 224 #define EXT2F_COMPAT_SPARSESUPER2 0x0200 225 226 #define EXT2F_ROCOMPAT_SPARSESUPER 0x0001 227 #define EXT2F_ROCOMPAT_LARGEFILE 0x0002 228 #define EXT2F_ROCOMPAT_BTREE_DIR 0x0004 229 #define EXT2F_ROCOMPAT_HUGE_FILE 0x0008 230 #define EXT2F_ROCOMPAT_GDT_CSUM 0x0010 231 #define EXT2F_ROCOMPAT_DIR_NLINK 0x0020 232 #define EXT2F_ROCOMPAT_EXTRA_ISIZE 0x0040 233 #define EXT2F_ROCOMPAT_HAS_SNAPSHOT 0x0080 234 #define EXT2F_ROCOMPAT_QUOTA 0x0100 235 #define EXT2F_ROCOMPAT_BIGALLOC 0x0200 236 #define EXT2F_ROCOMPAT_METADATA_CKSUM 0x0400 237 #define EXT2F_ROCOMPAT_REPLICA 0x0800 238 #define EXT2F_ROCOMPAT_READONLY 0x1000 239 #define EXT2F_ROCOMPAT_PROJECT 0x2000 240 241 #define EXT2F_INCOMPAT_COMP 0x0001 242 #define EXT2F_INCOMPAT_FTYPE 0x0002 243 #define EXT2F_INCOMPAT_RECOVER 0x0004 244 #define EXT2F_INCOMPAT_JOURNAL_DEV 0x0008 245 #define EXT2F_INCOMPAT_META_BG 0x0010 246 #define EXT2F_INCOMPAT_EXTENTS 0x0040 247 #define EXT2F_INCOMPAT_64BIT 0x0080 248 #define EXT2F_INCOMPAT_MMP 0x0100 249 #define EXT2F_INCOMPAT_FLEX_BG 0x0200 250 #define EXT2F_INCOMPAT_EA_INODE 0x0400 251 #define EXT2F_INCOMPAT_DIRDATA 0x1000 252 #define EXT2F_INCOMPAT_CSUM_SEED 0x2000 253 #define EXT2F_INCOMPAT_LARGEDIR 0x4000 254 #define EXT2F_INCOMPAT_INLINE_DATA 0x8000 255 #define EXT2F_INCOMPAT_ENCRYPT 0x10000 256 257 struct ext2_feature 258 { 259 int mask; 260 const char *name; 261 }; 262 263 static const struct ext2_feature compat[] = { 264 { EXT2F_COMPAT_PREALLOC, "dir_prealloc" }, 265 { EXT2F_COMPAT_IMAGIC_INODES, "imagic_inodes" }, 266 { EXT2F_COMPAT_HASJOURNAL, "has_journal" }, 267 { EXT2F_COMPAT_EXT_ATTR, "ext_attr" }, 268 { EXT2F_COMPAT_RESIZE, "resize_inode" }, 269 { EXT2F_COMPAT_DIRHASHINDEX, "dir_index" }, 270 { EXT2F_COMPAT_EXCLUDE_BITMAP, "snapshot_bitmap" }, 271 { EXT2F_COMPAT_SPARSESUPER2, "sparse_super2" } 272 }; 273 274 static const struct ext2_feature ro_compat[] = { 275 { EXT2F_ROCOMPAT_SPARSESUPER, "sparse_super" }, 276 { EXT2F_ROCOMPAT_LARGEFILE, "large_file" }, 277 { EXT2F_ROCOMPAT_BTREE_DIR, "btree_dir" }, 278 { EXT2F_ROCOMPAT_HUGE_FILE, "huge_file" }, 279 { EXT2F_ROCOMPAT_GDT_CSUM, "uninit_groups" }, 280 { EXT2F_ROCOMPAT_DIR_NLINK, "dir_nlink" }, 281 { EXT2F_ROCOMPAT_EXTRA_ISIZE, "extra_isize" }, 282 { EXT2F_ROCOMPAT_HAS_SNAPSHOT, "snapshot" }, 283 { EXT2F_ROCOMPAT_QUOTA, "quota" }, 284 { EXT2F_ROCOMPAT_BIGALLOC, "bigalloc" }, 285 { EXT2F_ROCOMPAT_METADATA_CKSUM, "metadata_csum" }, 286 { EXT2F_ROCOMPAT_REPLICA, "replica" }, 287 { EXT2F_ROCOMPAT_READONLY, "ro" }, 288 { EXT2F_ROCOMPAT_PROJECT, "project" } 289 }; 290 291 static const struct ext2_feature incompat[] = { 292 { EXT2F_INCOMPAT_COMP, "compression" }, 293 { EXT2F_INCOMPAT_FTYPE, "filetype" }, 294 { EXT2F_INCOMPAT_RECOVER, "needs_recovery" }, 295 { EXT2F_INCOMPAT_JOURNAL_DEV, "journal_dev" }, 296 { EXT2F_INCOMPAT_META_BG, "meta_bg" }, 297 { EXT2F_INCOMPAT_EXTENTS, "extents" }, 298 { EXT2F_INCOMPAT_64BIT, "64bit" }, 299 { EXT2F_INCOMPAT_MMP, "mmp" }, 300 { EXT2F_INCOMPAT_FLEX_BG, "flex_bg" }, 301 { EXT2F_INCOMPAT_EA_INODE, "ea_inode" }, 302 { EXT2F_INCOMPAT_DIRDATA, "dirdata" }, 303 { EXT2F_INCOMPAT_CSUM_SEED, "metadata_csum_seed" }, 304 { EXT2F_INCOMPAT_LARGEDIR, "large_dir" }, 305 { EXT2F_INCOMPAT_INLINE_DATA, "inline_data" }, 306 { EXT2F_INCOMPAT_ENCRYPT, "encrypt" } 307 }; 308 309 /* 310 * Features supported in this implementation 311 * 312 * We support the following REV1 features: 313 * - EXT2F_ROCOMPAT_SPARSESUPER 314 * - EXT2F_ROCOMPAT_LARGEFILE 315 * - EXT2F_ROCOMPAT_EXTRA_ISIZE 316 * - EXT2F_INCOMPAT_FTYPE 317 * 318 * We partially (read-only) support the following EXT4 features: 319 * - EXT2F_ROCOMPAT_HUGE_FILE 320 * - EXT2F_INCOMPAT_EXTENTS 321 * 322 */ 323 #define EXT2F_COMPAT_SUPP EXT2F_COMPAT_DIRHASHINDEX 324 #define EXT2F_ROCOMPAT_SUPP (EXT2F_ROCOMPAT_SPARSESUPER | \ 325 EXT2F_ROCOMPAT_LARGEFILE | \ 326 EXT2F_ROCOMPAT_GDT_CSUM | \ 327 EXT2F_ROCOMPAT_METADATA_CKSUM | \ 328 EXT2F_ROCOMPAT_DIR_NLINK | \ 329 EXT2F_ROCOMPAT_HUGE_FILE | \ 330 EXT2F_ROCOMPAT_EXTRA_ISIZE) 331 #define EXT2F_INCOMPAT_SUPP (EXT2F_INCOMPAT_FTYPE | \ 332 EXT2F_INCOMPAT_META_BG | \ 333 EXT2F_INCOMPAT_EXTENTS | \ 334 EXT2F_INCOMPAT_64BIT | \ 335 EXT2F_INCOMPAT_FLEX_BG | \ 336 EXT2F_INCOMPAT_CSUM_SEED) 337 338 /* Assume that user mode programs are passing in an ext2fs superblock, not 339 * a kernel struct super_block. This will allow us to call the feature-test 340 * macros from user land. */ 341 #define EXT2_SB(sb) (sb) 342 343 /* 344 * Feature set definitions 345 */ 346 #define EXT2_HAS_COMPAT_FEATURE(sb,mask) \ 347 ( le32toh(EXT2_SB(sb)->e2fs->e2fs_features_compat) & mask) 348 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \ 349 ( le32toh(EXT2_SB(sb)->e2fs->e2fs_features_rocompat) & mask) 350 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \ 351 ( le32toh(EXT2_SB(sb)->e2fs->e2fs_features_incompat) & mask) 352 353 /* 354 * File clean flags 355 */ 356 #define E2FS_ISCLEAN 0x0001 /* Unmounted cleanly */ 357 #define E2FS_ERRORS 0x0002 /* Errors detected */ 358 359 /* 360 * Filesystem miscellaneous flags 361 */ 362 #define E2FS_SIGNED_HASH 0x0001 363 #define E2FS_UNSIGNED_HASH 0x0002 364 365 #define EXT2_BG_INODE_UNINIT 0x0001 /* Inode table/bitmap not in use */ 366 #define EXT2_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not in use */ 367 #define EXT2_BG_INODE_ZEROED 0x0004 /* On-disk itable initialized to zero */ 368 369 /* ext2 file system block group descriptor */ 370 371 struct ext2_gd { 372 uint32_t ext2bgd_b_bitmap; /* blocks bitmap block */ 373 uint32_t ext2bgd_i_bitmap; /* inodes bitmap block */ 374 uint32_t ext2bgd_i_tables; /* inodes table block */ 375 uint16_t ext2bgd_nbfree; /* number of free blocks */ 376 uint16_t ext2bgd_nifree; /* number of free inodes */ 377 uint16_t ext2bgd_ndirs; /* number of directories */ 378 uint16_t ext4bgd_flags; /* block group flags */ 379 uint32_t ext4bgd_x_bitmap; /* snapshot exclusion bitmap loc. */ 380 uint16_t ext4bgd_b_bmap_csum; /* block bitmap checksum */ 381 uint16_t ext4bgd_i_bmap_csum; /* inode bitmap checksum */ 382 uint16_t ext4bgd_i_unused; /* unused inode count */ 383 uint16_t ext4bgd_csum; /* group descriptor checksum */ 384 uint32_t ext4bgd_b_bitmap_hi; /* high bits of blocks bitmap block */ 385 uint32_t ext4bgd_i_bitmap_hi; /* high bits of inodes bitmap block */ 386 uint32_t ext4bgd_i_tables_hi; /* high bits of inodes table block */ 387 uint16_t ext4bgd_nbfree_hi; /* high bits of number of free blocks */ 388 uint16_t ext4bgd_nifree_hi; /* high bits of number of free inodes */ 389 uint16_t ext4bgd_ndirs_hi; /* high bits of number of directories */ 390 uint16_t ext4bgd_i_unused_hi; /* high bits of unused inode count */ 391 uint32_t ext4bgd_x_bitmap_hi; /* high bits of snapshot exclusion */ 392 uint16_t ext4bgd_b_bmap_csum_hi;/* high bits of block bitmap checksum */ 393 uint16_t ext4bgd_i_bmap_csum_hi;/* high bits of inode bitmap checksum */ 394 uint32_t ext4bgd_reserved; 395 }; 396 397 #define E2FS_REV0_GD_SIZE (sizeof(struct ext2_gd) / 2) 398 #define E2FS_64BIT_GD_SIZE (sizeof(struct ext2_gd)) 399 400 /* 401 * Macro-instructions used to manage several block sizes 402 */ 403 #define EXT2_MIN_BLOCK_LOG_SIZE 10 404 #define EXT2_BLOCK_SIZE(s) ((s)->e2fs_bsize) 405 #define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof(uint32_t)) 406 #define EXT2_INODE_SIZE(s) (EXT2_SB(s)->e2fs_isize) 407 408 /* 409 * Macro-instructions used to manage fragments 410 */ 411 #define EXT2_MIN_FRAG_SIZE 1024 412 #define EXT2_MIN_FRAG_LOG_SIZE 10 413 #define EXT2_MAX_FRAG_LOG_SIZE 30 414 #define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->e2fs_fsize) 415 #define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->e2fs_fpb) 416 417 /* 418 * Macro-instructions used to manage group descriptors 419 */ 420 #define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->e2fs_bpg) 421 #define EXT2_DESCS_PER_BLOCK(s) (EXT2_HAS_INCOMPAT_FEATURE((s), \ 422 EXT2F_INCOMPAT_64BIT) ? ((s)->e2fs_bsize / sizeof(struct ext2_gd)) : \ 423 ((s)->e2fs_bsize / E2FS_REV0_GD_SIZE)) 424 425 /* 426 * Macro-instructions used to manage inodes 427 */ 428 #define EXT2_FIRST_INO(s) (le32toh((EXT2_SB(s)->e2fs->e2fs_rev) == \ 429 E2FS_REV0) ? EXT2_FIRSTINO : le32toh(EXT2_SB(s)->e2fs->e2fs_first_ino)) 430 431 /* 432 * Linux major/minor values limits 433 */ 434 #define EXT2_MINORBITS (20) 435 #define EXT2_MAJOR_MAX (0xffffffff >> EXT2_MINORBITS) 436 #define EXT2_MINOR_MAX ((1 << EXT2_MINORBITS) - 1) 437 438 #endif /* !_FS_EXT2FS_EXT2FS_H_ */ 439