1 /* $NetBSD: ext2fs.h,v 1.53 2025/05/04 20:26:56 rillig Exp $ */ 2 3 /* 4 * Copyright (c) 1982, 1986, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)fs.h 8.10 (Berkeley) 10/27/94 32 * Modified for ext2fs by Manuel Bouyer. 33 */ 34 35 /* 36 * Copyright (c) 1997 Manuel Bouyer. 37 * 38 * Redistribution and use in source and binary forms, with or without 39 * modification, are permitted provided that the following conditions 40 * are met: 41 * 1. Redistributions of source code must retain the above copyright 42 * notice, this list of conditions and the following disclaimer. 43 * 2. Redistributions in binary form must reproduce the above copyright 44 * notice, this list of conditions and the following disclaimer in the 45 * documentation and/or other materials provided with the distribution. 46 * 47 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 48 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 49 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 50 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 51 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 52 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 53 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 54 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 55 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 56 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 57 * 58 * @(#)fs.h 8.10 (Berkeley) 10/27/94 59 * Modified for ext2fs by Manuel Bouyer. 60 */ 61 62 #ifndef _UFS_EXT2FS_EXT2FS_H_ 63 #define _UFS_EXT2FS_EXT2FS_H_ 64 65 #include <sys/bswap.h> 66 67 /* 68 * Each disk drive contains some number of file systems. 69 * A file system consists of a number of cylinder groups. 70 * Each cylinder group has inodes and data. 71 * 72 * A file system is described by its super-block, which in turn 73 * describes the cylinder groups. The super-block is critical 74 * data and is replicated in each cylinder group to protect against 75 * catastrophic loss. This is done at `newfs' time and the critical 76 * super-block data does not change, so the copies need not be 77 * referenced further unless disaster strikes. 78 * 79 * The first boot and super blocks are given in absolute disk addresses. 80 * The byte-offset forms are preferred, as they don't imply a sector size. 81 */ 82 #define BBSIZE 1024 83 #define SBSIZE 1024 84 #define BBOFF ((off_t)(0)) 85 #define SBOFF ((off_t)(BBOFF + BBSIZE)) 86 #define BBLOCK ((daddr_t)(0)) 87 #define SBLOCK ((daddr_t)(BBLOCK + BBSIZE / DEV_BSIZE)) 88 89 #define fsbtodb(fs, b) ((daddr_t)(b) << (fs)->e2fs_fsbtodb) 90 /* calculates (loc / fs->fs_bsize) */ 91 #define lblkno(fs, loc) ((loc) >> (fs->e2fs_bshift)) 92 #define blksize(fs, ip, lbn) ((fs)->e2fs_bsize) 93 94 /* 95 * Addresses stored in inodes are capable of addressing blocks 96 * XXX 97 */ 98 99 /* 100 * MINBSIZE is the smallest allowable block size. 101 * MINBSIZE must be big enough to hold a cylinder group block, 102 * thus changes to (struct cg) must keep its size within MINBSIZE. 103 * Note that super blocks are always of size SBSIZE, 104 * and that both SBSIZE and MAXBSIZE must be >= MINBSIZE. 105 */ 106 #define LOG_MINBSIZE 10 107 #define MINBSIZE (1 << LOG_MINBSIZE) 108 109 /* 110 * The path name on which the file system is mounted is maintained 111 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in 112 * the super block for this name. 113 */ 114 #define MAXMNTLEN 512 115 116 /* 117 * MINFREE gives the minimum acceptable percentage of file system 118 * blocks which may be free. If the freelist drops below this level 119 * only the superuser may continue to allocate blocks. This may 120 * be set to 0 if no reserve of free blocks is deemed necessary, 121 * however throughput drops by fifty percent if the file system 122 * is run at between 95% and 100% full; thus the minimum default 123 * value of fs_minfree is 5%. However, to get good clustering 124 * performance, 10% is a better choice. hence we use 10% as our 125 * default value. With 10% free space, fragmentation is not a 126 * problem, so we choose to optimize for time. 127 */ 128 #define MINFREE 5 129 130 /* 131 * This is maximum amount of links allowed for files. For directories, 132 * going over this means setting DIR_NLINK feature. 133 */ 134 #define EXT2FS_LINK_MAX 65000 135 #define EXT2FS_LINK_INF 1 /* link count unknown */ 136 137 /* 138 * Super block for an ext2fs file system. 139 */ 140 struct ext2fs { 141 uint32_t e2fs_icount; /* Inode count */ 142 uint32_t e2fs_bcount; /* blocks count */ 143 uint32_t e2fs_rbcount; /* reserved blocks count */ 144 uint32_t e2fs_fbcount; /* free blocks count */ 145 uint32_t e2fs_ficount; /* free inodes count */ 146 uint32_t e2fs_first_dblock; /* first data block */ 147 uint32_t e2fs_log_bsize; /* bsize = 1024*(2^e2fs_log_bsize) */ 148 uint32_t e2fs_fsize; /* fragment size */ 149 uint32_t e2fs_bpg; /* blocks per group */ 150 uint32_t e2fs_fpg; /* frags per group */ 151 uint32_t e2fs_ipg; /* inodes per group */ 152 uint32_t e2fs_mtime; /* mount time */ 153 uint32_t e2fs_wtime; /* write time */ 154 uint16_t e2fs_mnt_count; /* mount count */ 155 uint16_t e2fs_max_mnt_count; /* max mount count */ 156 uint16_t e2fs_magic; /* magic number */ 157 uint16_t e2fs_state; /* file system state */ 158 uint16_t e2fs_beh; /* behavior on errors */ 159 uint16_t e2fs_minrev; /* minor revision level */ 160 uint32_t e2fs_lastfsck; /* time of last fsck */ 161 uint32_t e2fs_fsckintv; /* max time between fscks */ 162 uint32_t e2fs_creator; /* creator OS */ 163 uint32_t e2fs_rev; /* revision level */ 164 uint16_t e2fs_ruid; /* default uid for reserved blocks */ 165 uint16_t e2fs_rgid; /* default gid for reserved blocks */ 166 /* EXT2_DYNAMIC_REV superblocks */ 167 uint32_t e2fs_first_ino; /* first non-reserved inode */ 168 uint16_t e2fs_inode_size; /* size of inode structure */ 169 uint16_t e2fs_block_group_nr; /* block grp number of this sblk*/ 170 uint32_t e2fs_features_compat; /* compatible feature set */ 171 uint32_t e2fs_features_incompat; /* incompatible feature set */ 172 uint32_t e2fs_features_rocompat; /* RO-compatible feature set */ 173 uint8_t e2fs_uuid[16]; /* 128-bit uuid for volume */ 174 char e2fs_vname[16]; /* volume name */ 175 char e2fs_fsmnt[64]; /* name mounted on */ 176 uint32_t e2fs_algo; /* For compression */ 177 uint8_t e2fs_prealloc; /* # of blocks to preallocate */ 178 uint8_t e2fs_dir_prealloc; /* # of blocks to preallocate for dir */ 179 uint16_t e2fs_reserved_ngdb; /* # of reserved gd blocks for resize */ 180 181 /* Additional fields */ 182 char e3fs_journal_uuid[16];/* uuid of journal superblock */ 183 uint32_t e3fs_journal_inum; /* inode number of journal file */ 184 uint32_t e3fs_journal_dev; /* device number of journal file */ 185 uint32_t e3fs_last_orphan; /* start of list of inodes to delete */ 186 uint32_t e3fs_hash_seed[4]; /* HTREE hash seed */ 187 char e3fs_def_hash_version;/* Default hash version to use */ 188 char e3fs_jnl_backup_type; 189 uint16_t e3fs_desc_size; /* size of group descriptor */ 190 uint32_t e3fs_default_mount_opts; 191 uint32_t e3fs_first_meta_bg; /* First metablock block group */ 192 uint32_t e3fs_mkfs_time; /* when the fs was created */ 193 uint32_t e3fs_jnl_blks[17]; /* backup of the journal inode */ 194 uint32_t e4fs_bcount_hi; /* high bits of blocks count */ 195 uint32_t e4fs_rbcount_hi; /* high bits of reserved blocks count */ 196 uint32_t e4fs_fbcount_hi; /* high bits of free blocks count */ 197 uint16_t e4fs_min_extra_isize; /* all inodes have some bytes */ 198 uint16_t e4fs_want_extra_isize;/* inodes must reserve some bytes */ 199 uint32_t e4fs_flags; /* miscellaneous flags */ 200 uint16_t e4fs_raid_stride; /* RAID stride */ 201 uint16_t e4fs_mmpintv; /* seconds to wait in MMP checking */ 202 uint64_t e4fs_mmpblk; /* block for multi-mount protection */ 203 uint32_t e4fs_raid_stripe_wid; /* blocks on data disks (N * stride) */ 204 uint8_t e4fs_log_gpf; /* FLEX_BG group size */ 205 uint8_t e4fs_chksum_type; /* metadata checksum algorithm used */ 206 uint8_t e4fs_encrypt; /* versioning level for encryption */ 207 uint8_t e4fs_reserved_pad; 208 uint64_t e4fs_kbytes_written; /* number of lifetime kilobytes */ 209 uint32_t e4fs_snapinum; /* inode number of active snapshot */ 210 uint32_t e4fs_snapid; /* sequential ID of active snapshot */ 211 uint64_t e4fs_snaprbcount; /* rsvd blocks for active snapshot */ 212 uint32_t e4fs_snaplist; /* inode number for on-disk snapshot */ 213 uint32_t e4fs_errcount; /* number of file system errors */ 214 uint32_t e4fs_first_errtime; /* first time an error happened */ 215 uint32_t e4fs_first_errino; /* inode involved in first error */ 216 uint64_t e4fs_first_errblk; /* block involved of first error */ 217 uint8_t e4fs_first_errfunc[32];/* function where error happened */ 218 uint32_t e4fs_first_errline; /* line number where error happened */ 219 uint32_t e4fs_last_errtime; /* most recent time of an error */ 220 uint32_t e4fs_last_errino; /* inode involved in last error */ 221 uint32_t e4fs_last_errline; /* line number where error happened */ 222 uint64_t e4fs_last_errblk; /* block involved of last error */ 223 uint8_t e4fs_last_errfunc[32];/* function where error happened */ 224 uint8_t e4fs_mount_opts[64]; 225 uint32_t e4fs_usrquota_inum; /* inode for tracking user quota */ 226 uint32_t e4fs_grpquota_inum; /* inode for tracking group quota */ 227 uint32_t e4fs_overhead_clusters;/* overhead blocks/clusters */ 228 uint32_t e4fs_backup_bgs[2]; /* groups with sparse_super2 SBs */ 229 uint8_t e4fs_encrypt_algos[4];/* encryption algorithms in use */ 230 uint8_t e4fs_encrypt_pw_salt[16];/* salt used for string2key */ 231 uint32_t e4fs_lpf_ino; /* location of the lost+found inode */ 232 uint32_t e4fs_proj_quota_inum; /* inode for tracking project quota */ 233 uint32_t e4fs_chksum_seed; /* checksum seed */ 234 uint32_t e4fs_reserved[98]; /* padding to the end of the block */ 235 uint32_t e4fs_sbchksum; /* superblock checksum */ 236 }; 237 238 239 /* in-memory data for ext2fs */ 240 struct m_ext2fs { 241 struct ext2fs e2fs; 242 u_char e2fs_fsmnt[MAXMNTLEN]; /* name mounted on */ 243 int8_t e2fs_ronly; /* mounted read-only flag */ 244 int8_t e2fs_fmod; /* super block modified flag */ 245 int8_t e2fs_uhash; /* 3 if hash should be signed, 0 if not */ 246 int32_t e2fs_bsize; /* block size */ 247 int32_t e2fs_bshift; /* ``lblkno'' calc of logical blkno */ 248 int32_t e2fs_bmask; /* ``blkoff'' calc of blk offsets */ 249 int64_t e2fs_qbmask; /* ~fs_bmask - for use with quad size */ 250 int32_t e2fs_fsbtodb; /* fsbtodb and dbtofsb shift constant */ 251 int32_t e2fs_ncg; /* number of cylinder groups */ 252 int32_t e2fs_ngdb; /* number of group descriptor blocks */ 253 int32_t e2fs_ipb; /* number of inodes per block */ 254 int32_t e2fs_itpg; /* number of inode table blocks per group */ 255 uint8_t e2fs_group_desc_shift; /* binary log group desc size */ 256 struct ext2_gd *e2fs_gd; /* group descriptors (data not byteswapped) */ 257 }; 258 259 260 261 /* 262 * Filesystem identification 263 */ 264 #define E2FS_MAGIC 0xef53 /* the ext2fs magic number */ 265 #define E2FS_REV0 0 /* GOOD_OLD revision */ 266 #define E2FS_REV1 1 /* Support compat/incompat features */ 267 268 /* compatible/incompatible features */ 269 #define EXT2F_COMPAT_PREALLOC 0x0001 270 #define EXT2F_COMPAT_AFS 0x0002 271 #define EXT2F_COMPAT_HASJOURNAL 0x0004 272 #define EXT2F_COMPAT_EXTATTR 0x0008 273 #define EXT2F_COMPAT_RESIZE 0x0010 274 #define EXT2F_COMPAT_DIRHASHINDEX 0x0020 275 #define EXT2F_COMPAT_SPARSESUPER2 0x0200 276 #define EXT2F_COMPAT_BITS \ 277 "\20" \ 278 "\12COMPAT_SPARSESUPER2" \ 279 "\11" \ 280 "\10" \ 281 "\07" \ 282 "\06COMPAT_DIRHASHINDEX" \ 283 "\05COMPAT_RESIZE" \ 284 "\04COMPAT_EXTATTR" \ 285 "\03COMPAT_HASJOURNAL" \ 286 "\02COMPAT_AFS" \ 287 "\01COMPAT_PREALLOC" 288 289 #define EXT2F_ROCOMPAT_SPARSESUPER 0x0001 290 #define EXT2F_ROCOMPAT_LARGEFILE 0x0002 291 #define EXT2F_ROCOMPAT_BTREE_DIR 0x0004 292 #define EXT2F_ROCOMPAT_HUGE_FILE 0x0008 293 #define EXT2F_ROCOMPAT_GDT_CSUM 0x0010 294 #define EXT2F_ROCOMPAT_DIR_NLINK 0x0020 295 #define EXT2F_ROCOMPAT_EXTRA_ISIZE 0x0040 296 #define EXT2F_ROCOMPAT_QUOTA 0x0100 297 #define EXT2F_ROCOMPAT_BIGALLOC 0x0200 298 #define EXT2F_ROCOMPAT_METADATA_CKSUM 0x0400 299 #define EXT2F_ROCOMPAT_READONLY 0x1000 300 #define EXT2F_ROCOMPAT_PROJECT 0x2000 301 #define EXT2F_ROCOMPAT_BITS \ 302 "\20" \ 303 "\16ROCOMPAT_PROJECT" \ 304 "\15ROCOMPAT_READONLY" \ 305 "\14?" \ 306 "\13ROCOMPAT_METADATA_CKSUM" \ 307 "\12ROCOMPAT_BIGALLOC" \ 308 "\11ROCOMPAT_QUOTA" \ 309 "\10?" \ 310 "\07ROCOMPAT_EXTRA_ISIZE" \ 311 "\06ROCOMPAT_DIR_NLINK" \ 312 "\05ROCOMPAT_GDT_CSUM" \ 313 "\04ROCOMPAT_HUGE_FILE" \ 314 "\03ROCOMPAT_BTREE_DIR" \ 315 "\02ROCOMPAT_LARGEFILE" \ 316 "\01ROCOMPAT_SPARSESUPER" 317 318 #define EXT2F_INCOMPAT_COMP 0x0001 319 #define EXT2F_INCOMPAT_FTYPE 0x0002 320 #define EXT2F_INCOMPAT_REPLAY_JOURNAL 0x0004 321 #define EXT2F_INCOMPAT_USES_JOURNAL 0x0008 322 #define EXT2F_INCOMPAT_META_BG 0x0010 323 #define EXT2F_INCOMPAT_EXTENTS 0x0040 324 #define EXT2F_INCOMPAT_64BIT 0x0080 325 #define EXT2F_INCOMPAT_MMP 0x0100 326 #define EXT2F_INCOMPAT_FLEX_BG 0x0200 327 #define EXT2F_INCOMPAT_EA_INODE 0x0400 328 #define EXT2F_INCOMPAT_DIRDATA 0x1000 329 #define EXT2F_INCOMPAT_CSUM_SEED 0x2000 330 #define EXT2F_INCOMPAT_LARGEDIR 0x4000 331 #define EXT2F_INCOMPAT_INLINE_DATA 0x8000 332 #define EXT2F_INCOMPAT_ENCRYPT 0x10000 333 #define EXT2F_INCOMPAT_BITS \ 334 "\20" \ 335 "\021INCOMPAT_ENCRYPT" \ 336 "\020INCOMPAT_INLINE_DATA" \ 337 "\017INCOMPAT_LARGEDIR" \ 338 "\016INCOMPAT_CSUM_SEED" \ 339 "\015INCOMPAT_DIRDATA" \ 340 "\014?" \ 341 "\013INCOMPAT_EA_INODE" \ 342 "\012INCOMPAT_FLEX_BG" \ 343 "\011INCOMPAT_MMP" \ 344 "\010INCOMPAT_64BIT" \ 345 "\07INCOMPAT_EXTENTS" \ 346 "\05INCOMPAT_META_BG" \ 347 "\04INCOMPAT_USES_JOURNAL" \ 348 "\03INCOMPAT_REPLAY_JOURNAL" \ 349 "\02INCOMPAT_FTYPE" \ 350 "\01INCOMPAT_COMP" 351 352 /* 353 * Features supported in this implementation 354 * 355 * We support the following REV1 features: 356 * - EXT2F_ROCOMPAT_SPARSESUPER 357 * superblock backups stored only in cg_has_sb(bno) groups 358 * - EXT2F_ROCOMPAT_LARGEFILE 359 * use e2di_size_high in struct ext2fs_dinode to store 360 * upper 32bit of size for >2GB files 361 * - EXT2F_INCOMPAT_FTYPE 362 * store file type to e2d_type in struct ext2fs_direct 363 * (on REV0 e2d_namlen is uint16_t and no e2d_type, like ffs) 364 */ 365 #define EXT2F_COMPAT_SUPP 0x0000 366 #define EXT2F_ROCOMPAT_SUPP (EXT2F_ROCOMPAT_SPARSESUPER \ 367 | EXT2F_ROCOMPAT_LARGEFILE \ 368 | EXT2F_ROCOMPAT_HUGE_FILE \ 369 | EXT2F_ROCOMPAT_EXTRA_ISIZE \ 370 | EXT2F_ROCOMPAT_DIR_NLINK \ 371 | EXT2F_ROCOMPAT_GDT_CSUM) 372 #define EXT2F_INCOMPAT_SUPP (EXT2F_INCOMPAT_FTYPE \ 373 | EXT2F_INCOMPAT_EXTENTS \ 374 | EXT2F_INCOMPAT_FLEX_BG \ 375 | EXT2F_INCOMPAT_64BIT) 376 377 /* 378 * Feature set definitions 379 */ 380 #define EXT2F_HAS_COMPAT_FEATURE(fs, feature) \ 381 ((fs)->e2fs.e2fs_rev >= E2FS_REV1 && \ 382 ((fs)->e2fs.e2fs_features_compat & (feature)) != 0) 383 384 #define EXT2F_HAS_ROCOMPAT_FEATURE(fs, feature) \ 385 ((fs)->e2fs.e2fs_rev >= E2FS_REV1 && \ 386 ((fs)->e2fs.e2fs_features_rocompat & (feature)) != 0) 387 388 #define EXT2F_HAS_INCOMPAT_FEATURE(fs, feature) \ 389 ((fs)->e2fs.e2fs_rev >= E2FS_REV1 && \ 390 ((fs)->e2fs.e2fs_features_incompat & (feature)) != 0) 391 392 393 /* 394 * Definitions of behavior on errors 395 */ 396 #define E2FS_BEH_CONTINUE 1 /* continue operation */ 397 #define E2FS_BEH_READONLY 2 /* remount fs read only */ 398 #define E2FS_BEH_PANIC 3 /* cause panic */ 399 #define E2FS_BEH_DEFAULT E2FS_BEH_CONTINUE 400 401 /* 402 * OS identification 403 */ 404 #define E2FS_OS_LINUX 0 405 #define E2FS_OS_HURD 1 406 #define E2FS_OS_MASIX 2 407 #define E2FS_OS_FREEBSD 3 408 #define E2FS_OS_LITES 4 409 410 /* 411 * Filesystem clean flags 412 */ 413 #define E2FS_ISCLEAN 0x01 414 #define E2FS_ERRORS 0x02 415 416 /* ext2 file system block group descriptor */ 417 418 struct ext2_gd { 419 uint32_t ext2bgd_b_bitmap; /* blocks bitmap block */ 420 uint32_t ext2bgd_i_bitmap; /* inodes bitmap block */ 421 uint32_t ext2bgd_i_tables; /* first inodes table block */ 422 uint16_t ext2bgd_nbfree; /* number of free blocks */ 423 uint16_t ext2bgd_nifree; /* number of free inodes */ 424 uint16_t ext2bgd_ndirs; /* number of directories */ 425 426 /* 427 * Following only valid when either GDT_CSUM (AKA uninit_bg) 428 * or METADATA_CKSUM feature is on 429 */ 430 uint16_t ext2bgd_flags; /* ext4 bg flags (INODE_UNINIT, ...)*/ 431 uint32_t ext2bgd_exclude_bitmap_lo; /* snapshot exclude bitmap */ 432 uint16_t ext2bgd_block_bitmap_csum_lo; /* Low block bitmap checksum */ 433 uint16_t ext2bgd_inode_bitmap_csum_lo; /* Low inode bitmap checksum */ 434 uint16_t ext2bgd_itable_unused_lo; /* Low unused inode offset */ 435 uint16_t ext2bgd_checksum; /* Group desc checksum */ 436 437 uint32_t ext2bgd_b_bitmap_hi; /* blocks bitmap block (high bits) */ 438 uint32_t ext2bgd_i_bitmap_hi; /* inodes bitmap block (high bits) */ 439 uint32_t ext2bgd_i_tables_hi; /* inodes table block (high bits) */ 440 uint16_t ext2bgd_nbfree_hi; /* number of free blocks (high bits) */ 441 uint16_t ext2bgd_nifree_hi; /* number of free inodes (high bits) */ 442 uint16_t ext2bgd_ndirs_hi; /* number of directories (high bits) */ 443 uint16_t reserved_hi; 444 uint32_t reserved2_hi[3]; 445 }; 446 447 #define E2FS_REV0_GD_SIZE (sizeof(struct ext2_gd) / 2) /* 32 */ 448 #define E2FS_BG_INODE_UNINIT 0x0001 /* Inode bitmap not used/initialized */ 449 #define E2FS_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not used/initialized */ 450 #define E2FS_BG_INODE_ZEROED 0x0004 /* On-disk inode table initialized */ 451 452 #define E2FS_HAS_GD_CSUM(fs) \ 453 EXT2F_HAS_ROCOMPAT_FEATURE(fs, EXT2F_ROCOMPAT_GDT_CSUM|EXT2F_ROCOMPAT_METADATA_CKSUM) != 0 454 455 /* 456 * If the EXT2F_ROCOMPAT_SPARSESUPER flag is set, the cylinder group has a 457 * copy of the super and cylinder group descriptors blocks only if it's 458 * 1, a power of 3, 5 or 7 459 */ 460 461 static __inline int cg_has_sb(int) __unused; 462 static __inline int 463 cg_has_sb(int i) 464 { 465 int a3, a5, a7; 466 467 if (i == 0 || i == 1) 468 return 1; 469 for (a3 = 3, a5 = 5, a7 = 7; 470 a3 <= i || a5 <= i || a7 <= i; 471 a3 *= 3, a5 *= 5, a7 *= 7) 472 if (i == a3 || i == a5 || i == a7) 473 return 1; 474 return 0; 475 } 476 477 /* EXT2FS metadatas are stored in little-endian byte order. These macros 478 * helps reading theses metadatas 479 */ 480 481 #if BYTE_ORDER == LITTLE_ENDIAN 482 # define h2fs16(x) (x) 483 # define h2fs32(x) (x) 484 # define h2fs64(x) (x) 485 # define fs2h16(x) (x) 486 # define fs2h32(x) (x) 487 # define fs2h64(x) (x) 488 # define e2fs_sbload(old, new) memcpy((new), (old), SBSIZE) 489 # define e2fs_sbsave(old, new) memcpy((new), (old), SBSIZE) 490 #else 491 void e2fs_sb_bswap(struct ext2fs *, struct ext2fs *); 492 # define h2fs16(x) bswap16(x) 493 # define h2fs32(x) bswap32(x) 494 # define h2fs64(x) bswap64(x) 495 # define fs2h16(x) bswap16(x) 496 # define fs2h32(x) bswap32(x) 497 # define fs2h64(x) bswap64(x) 498 # define e2fs_sbload(old, new) e2fs_sb_bswap((old), (new)) 499 # define e2fs_sbsave(old, new) e2fs_sb_bswap((old), (new)) 500 #endif 501 502 #ifndef _KERNEL /* XXX */ 503 /* Group descriptors are not byte swapped */ 504 #define e2fs_cgload(old, new, size) memcpy((new), (old), (size)) 505 #define e2fs_cgsave(old, new, size) memcpy((new), (old), (size)) 506 #endif 507 508 /* 509 * Turn file system block numbers into disk block addresses. 510 * This maps file system blocks to device size blocks. 511 */ 512 #define EXT2_FSBTODB(fs, b) ((b) << (fs)->e2fs_fsbtodb) 513 #define EXT2_FSBTODB64(fs, b, b_hi) \ 514 (((((uint64_t)(b_hi)) << 32) | (b)) << (fs)->e2fs_fsbtodb) 515 #define EXT2_FSBTODB64OFF(fs, b, b_hi, off) \ 516 ((((((uint64_t)(b_hi)) << 32) | (b)) + (off)) << (fs)->e2fs_fsbtodb) 517 #define EXT2_DBTOFSB(fs, b) ((b) >> (fs)->e2fs_fsbtodb) 518 519 /* 520 * Macros for handling inode numbers: 521 * inode number to file system block offset. 522 * inode number to cylinder group number. 523 * inode number to file system block address. 524 */ 525 #define ino_to_cg(fs, x) (((x) - 1) / (fs)->e2fs.e2fs_ipg) 526 #define _e2fs_gd(fs, x) (fs)->e2fs_gd[ino_to_cg((fs), (x))] 527 #define ino_to_fsba(fs, x) \ 528 (fs2h32(_e2fs_gd(fs, x).ext2bgd_i_tables) + \ 529 (((uint64_t)fs2h32(_e2fs_gd(fs, x).ext2bgd_i_tables_hi)) << 32) + \ 530 (((x) - 1) % (fs)->e2fs.e2fs_ipg) / (fs)->e2fs_ipb) 531 #define ino_to_fsbo(fs, x) (((x) - 1) % (fs)->e2fs_ipb) 532 533 /* 534 * Give cylinder group number for a file system block. 535 * Give cylinder group block number for a file system block. 536 */ 537 #define dtog(fs, d) (((d) - (fs)->e2fs.e2fs_first_dblock) / (fs)->e2fs.e2fs_fpg) 538 #define dtogd(fs, d) \ 539 (((d) - (fs)->e2fs.e2fs_first_dblock) % (fs)->e2fs.e2fs_fpg) 540 541 /* 542 * The following macros optimize certain frequently calculated 543 * quantities by using shifts and masks in place of divisions 544 * modulos and multiplications. 545 */ 546 #define ext2_blkoff(fs, loc) /* calculates (loc % fs->e2fs_bsize) */ \ 547 ((loc) & (fs)->e2fs_qbmask) 548 #define ext2_lblktosize(fs, blk) /* calculates (blk * fs->e2fs_bsize) */ \ 549 ((blk) << (fs)->e2fs_bshift) 550 #define ext2_lblkno(fs, loc) /* calculates (loc / fs->e2fs_bsize) */ \ 551 ((loc) >> (fs)->e2fs_bshift) 552 #define ext2_blkroundup(fs, size) /* calculates roundup(size, fs->e2fs_bsize) */ \ 553 (((size) + (fs)->e2fs_qbmask) & (fs)->e2fs_bmask) 554 #define ext2_fragroundup(fs, size) /* calculates roundup(size, fs->e2fs_bsize) */ \ 555 (((size) + (fs)->e2fs_qbmask) & (fs)->e2fs_bmask) 556 /* 557 * Determine the number of available frags given a 558 * percentage to hold in reserve. 559 */ 560 #define freespace(fs) \ 561 ((fs)->e2fs.e2fs_fbcount - (fs)->e2fs.e2fs_rbcount) 562 563 /* 564 * Number of indirects in a file system block. 565 */ 566 #define EXT2_NINDIR(fs) ((fs)->e2fs_bsize / sizeof(uint32_t)) 567 568 #endif /* !_UFS_EXT2FS_EXT2FS_H_ */ 569
Indexes created Sat Sep 20 22:09:52 GMT 2025