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 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 11 * 12 * Copyright (c) 2009 Aditya Sarawgi 13 * All rights reserved. 14 * 15 * Redistribution and use in source and binary forms, with or without 16 * modification, are permitted provided that the following conditions 17 * are met: 18 * 1. Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 2. Redistributions in binary form must reproduce the above copyright 21 * notice, this list of conditions and the following disclaimer in the 22 * documentation and/or other materials provided with the distribution. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * 37 */ 38 39 #ifndef _FS_EXT2FS_EXT2FS_H_ 40 #define _FS_EXT2FS_EXT2FS_H_ 41 42 #include <sys/types.h> 43 44 /* 45 * Super block for an ext2fs file system. 46 */ 47 struct ext2fs { 48 uint32_t e2fs_icount; /* Inode count */ 49 uint32_t e2fs_bcount; /* blocks count */ 50 uint32_t e2fs_rbcount; /* reserved blocks count */ 51 uint32_t e2fs_fbcount; /* free blocks count */ 52 uint32_t e2fs_ficount; /* free inodes count */ 53 uint32_t e2fs_first_dblock; /* first data block */ 54 uint32_t e2fs_log_bsize; /* block size = 1024*(2^e2fs_log_bsize) */ 55 uint32_t e2fs_log_fsize; /* fragment size */ 56 uint32_t e2fs_bpg; /* blocks per group */ 57 uint32_t e2fs_fpg; /* frags per group */ 58 uint32_t e2fs_ipg; /* inodes per group */ 59 uint32_t e2fs_mtime; /* mount time */ 60 uint32_t e2fs_wtime; /* write time */ 61 uint16_t e2fs_mnt_count; /* mount count */ 62 uint16_t e2fs_max_mnt_count; /* max mount count */ 63 uint16_t e2fs_magic; /* magic number */ 64 uint16_t e2fs_state; /* file system state */ 65 uint16_t e2fs_beh; /* behavior on errors */ 66 uint16_t e2fs_minrev; /* minor revision level */ 67 uint32_t e2fs_lastfsck; /* time of last fsck */ 68 uint32_t e2fs_fsckintv; /* max time between fscks */ 69 uint32_t e2fs_creator; /* creator OS */ 70 uint32_t e2fs_rev; /* revision level */ 71 uint16_t e2fs_ruid; /* default uid for reserved blocks */ 72 uint16_t e2fs_rgid; /* default gid for reserved blocks */ 73 /* EXT2_DYNAMIC_REV superblocks */ 74 uint32_t e2fs_first_ino; /* first non-reserved inode */ 75 uint16_t e2fs_inode_size; /* size of inode structure */ 76 uint16_t e2fs_block_group_nr; /* block grp number of this sblk*/ 77 uint32_t e2fs_features_compat; /* compatible feature set */ 78 uint32_t e2fs_features_incompat; /* incompatible feature set */ 79 uint32_t e2fs_features_rocompat; /* RO-compatible feature set */ 80 uint8_t e2fs_uuid[16]; /* 128-bit uuid for volume */ 81 char e2fs_vname[16]; /* volume name */ 82 char e2fs_fsmnt[64]; /* name mounted on */ 83 uint32_t e2fs_algo; /* For compression */ 84 uint8_t e2fs_prealloc; /* # of blocks for old prealloc */ 85 uint8_t e2fs_dir_prealloc; /* # of blocks for old prealloc dirs */ 86 uint16_t e2fs_reserved_ngdb; /* # of reserved gd blocks for resize */ 87 char e3fs_journal_uuid[16]; /* uuid of journal superblock */ 88 uint32_t e3fs_journal_inum; /* inode number of journal file */ 89 uint32_t e3fs_journal_dev; /* device number of journal file */ 90 uint32_t e3fs_last_orphan; /* start of list of inodes to delete */ 91 uint32_t e3fs_hash_seed[4]; /* HTREE hash seed */ 92 char e3fs_def_hash_version;/* Default hash version to use */ 93 char e3fs_jnl_backup_type; 94 uint16_t e3fs_desc_size; /* size of group descriptor */ 95 uint32_t e3fs_default_mount_opts; 96 uint32_t e3fs_first_meta_bg; /* First metablock block group */ 97 uint32_t e3fs_mkfs_time; /* when the fs was created */ 98 uint32_t e3fs_jnl_blks[17]; /* backup of the journal inode */ 99 uint32_t e4fs_bcount_hi; /* high bits of blocks count */ 100 uint32_t e4fs_rbcount_hi; /* high bits of reserved blocks count */ 101 uint32_t e4fs_fbcount_hi; /* high bits of free blocks count */ 102 uint16_t e4fs_min_extra_isize; /* all inodes have some bytes */ 103 uint16_t e4fs_want_extra_isize;/* inodes must reserve some bytes */ 104 uint32_t e4fs_flags; /* miscellaneous flags */ 105 uint16_t e4fs_raid_stride; /* RAID stride */ 106 uint16_t e4fs_mmpintv; /* seconds to wait in MMP checking */ 107 uint64_t e4fs_mmpblk; /* block for multi-mount protection */ 108 uint32_t e4fs_raid_stripe_wid; /* blocks on data disks (N * stride) */ 109 uint8_t e4fs_log_gpf; /* FLEX_BG group size */ 110 uint8_t e4fs_chksum_type; /* metadata checksum algorithm used */ 111 uint8_t e4fs_encrypt; /* versioning level for encryption */ 112 uint8_t e4fs_reserved_pad; 113 uint64_t e4fs_kbytes_written; /* number of lifetime kilobytes */ 114 uint32_t e4fs_snapinum; /* inode number of active snapshot */ 115 uint32_t e4fs_snapid; /* sequential ID of active snapshot */ 116 uint64_t e4fs_snaprbcount; /* reserved blocks for active snapshot */ 117 uint32_t e4fs_snaplist; /* inode number for on-disk snapshot */ 118 uint32_t e4fs_errcount; /* number of file system errors */ 119 uint32_t e4fs_first_errtime; /* first time an error happened */ 120 uint32_t e4fs_first_errino; /* inode involved in first error */ 121 uint64_t e4fs_first_errblk; /* block involved of first error */ 122 uint8_t e4fs_first_errfunc[32];/* function where error happened */ 123 uint32_t e4fs_first_errline; /* line number where error happened */ 124 uint32_t e4fs_last_errtime; /* most recent time of an error */ 125 uint32_t e4fs_last_errino; /* inode involved in last error */ 126 uint32_t e4fs_last_errline; /* line number where error happened */ 127 uint64_t e4fs_last_errblk; /* block involved of last error */ 128 uint8_t e4fs_last_errfunc[32]; /* function where error happened */ 129 uint8_t e4fs_mount_opts[64]; 130 uint32_t e4fs_usrquota_inum; /* inode for tracking user quota */ 131 uint32_t e4fs_grpquota_inum; /* inode for tracking group quota */ 132 uint32_t e4fs_overhead_clusters;/* overhead blocks/clusters */ 133 uint32_t e4fs_backup_bgs[2]; /* groups with sparse_super2 SBs */ 134 uint8_t e4fs_encrypt_algos[4];/* encryption algorithms in use */ 135 uint8_t e4fs_encrypt_pw_salt[16];/* salt used for string2key */ 136 uint32_t e4fs_lpf_ino; /* location of the lost+found inode */ 137 uint32_t e4fs_proj_quota_inum; /* inode for tracking project quota */ 138 uint32_t e4fs_chksum_seed; /* checksum seed */ 139 uint32_t e4fs_reserved[98]; /* padding to the end of the block */ 140 uint32_t e4fs_sbchksum; /* superblock checksum */ 141 }; 142 143 /* 144 * The path name on which the file system is mounted is maintained 145 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in 146 * the super block for this name. 147 */ 148 #define MAXMNTLEN 512 149 150 /* 151 * In-Memory Superblock 152 */ 153 154 struct m_ext2fs { 155 struct ext2fs * e2fs; 156 char e2fs_fsmnt[MAXMNTLEN];/* name mounted on */ 157 char e2fs_ronly; /* mounted read-only flag */ 158 char e2fs_fmod; /* super block modified flag */ 159 uint32_t e2fs_bsize; /* Block size */ 160 uint32_t e2fs_bshift; /* calc of logical block no */ 161 uint32_t e2fs_bpg; /* Number of blocks per group */ 162 int64_t e2fs_qbmask; /* = s_blocksize -1 */ 163 uint32_t e2fs_fsbtodb; /* Shift to get disk block */ 164 uint32_t e2fs_ipg; /* Number of inodes per group */ 165 uint32_t e2fs_ipb; /* Number of inodes per block */ 166 uint32_t e2fs_itpg; /* Number of inode table per group */ 167 uint32_t e2fs_fsize; /* Size of fragments per block */ 168 uint32_t e2fs_fpb; /* Number of fragments per block */ 169 uint32_t e2fs_fpg; /* Number of fragments per group */ 170 uint32_t e2fs_gdbcount; /* Number of group descriptors */ 171 uint32_t e2fs_gcount; /* Number of groups */ 172 uint32_t e2fs_isize; /* Size of inode */ 173 uint32_t e2fs_total_dir; /* Total number of directories */ 174 uint8_t *e2fs_contigdirs; /* (u) # of contig. allocated dirs */ 175 char e2fs_wasvalid; /* valid at mount time */ 176 off_t e2fs_maxfilesize; 177 struct ext2_gd *e2fs_gd; /* Group Descriptors */ 178 int32_t e2fs_contigsumsize; /* size of cluster summary array */ 179 int32_t *e2fs_maxcluster; /* max cluster in each cyl group */ 180 struct csum *e2fs_clustersum; /* cluster summary in each cyl group */ 181 int32_t e2fs_uhash; /* 3 if hash should be signed, 0 if not */ 182 }; 183 184 /* cluster summary information */ 185 186 struct csum { 187 int8_t cs_init; /* cluster summary has been initialized */ 188 int32_t *cs_sum; /* cluster summary array */ 189 }; 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_REV0_INODE_SIZE 128 203 204 /* 205 * compatible/incompatible features 206 */ 207 #define EXT2F_COMPAT_PREALLOC 0x0001 208 #define EXT2F_COMPAT_IMAGIC_INODES 0x0002 209 #define EXT2F_COMPAT_HASJOURNAL 0x0004 210 #define EXT2F_COMPAT_EXT_ATTR 0x0008 211 #define EXT2F_COMPAT_RESIZE 0x0010 212 #define EXT2F_COMPAT_DIRHASHINDEX 0x0020 213 #define EXT2F_COMPAT_LAZY_BG 0x0040 214 #define EXT2F_COMPAT_EXCLUDE_BITMAP 0x0100 215 #define EXT2F_COMPAT_SPARSESUPER2 0x0200 216 217 #define EXT2F_ROCOMPAT_SPARSESUPER 0x0001 218 #define EXT2F_ROCOMPAT_LARGEFILE 0x0002 219 #define EXT2F_ROCOMPAT_BTREE_DIR 0x0004 220 #define EXT2F_ROCOMPAT_HUGE_FILE 0x0008 221 #define EXT2F_ROCOMPAT_GDT_CSUM 0x0010 222 #define EXT2F_ROCOMPAT_DIR_NLINK 0x0020 223 #define EXT2F_ROCOMPAT_EXTRA_ISIZE 0x0040 224 #define EXT2F_ROCOMPAT_HAS_SNAPSHOT 0x0080 225 #define EXT2F_ROCOMPAT_QUOTA 0x0100 226 #define EXT2F_ROCOMPAT_BIGALLOC 0x0200 227 #define EXT2F_ROCOMPAT_METADATA_CKSUM 0x0400 228 #define EXT2F_ROCOMPAT_REPLICA 0x0800 229 #define EXT2F_ROCOMPAT_READONLY 0x1000 230 #define EXT2F_ROCOMPAT_PROJECT 0x2000 231 232 #define EXT2F_INCOMPAT_COMP 0x0001 233 #define EXT2F_INCOMPAT_FTYPE 0x0002 234 #define EXT2F_INCOMPAT_RECOVER 0x0004 235 #define EXT2F_INCOMPAT_JOURNAL_DEV 0x0008 236 #define EXT2F_INCOMPAT_META_BG 0x0010 237 #define EXT2F_INCOMPAT_EXTENTS 0x0040 238 #define EXT2F_INCOMPAT_64BIT 0x0080 239 #define EXT2F_INCOMPAT_MMP 0x0100 240 #define EXT2F_INCOMPAT_FLEX_BG 0x0200 241 #define EXT2F_INCOMPAT_EA_INODE 0x0400 242 #define EXT2F_INCOMPAT_DIRDATA 0x1000 243 #define EXT2F_INCOMPAT_CSUM_SEED 0x2000 244 #define EXT2F_INCOMPAT_LARGEDIR 0x4000 245 #define EXT2F_INCOMPAT_INLINE_DATA 0x8000 246 #define EXT2F_INCOMPAT_ENCRYPT 0x10000 247 248 struct ext2_feature 249 { 250 int mask; 251 const char *name; 252 }; 253 254 static const struct ext2_feature compat[] = { 255 { EXT2F_COMPAT_PREALLOC, "dir_prealloc" }, 256 { EXT2F_COMPAT_IMAGIC_INODES, "imagic_inodes" }, 257 { EXT2F_COMPAT_HASJOURNAL, "has_journal" }, 258 { EXT2F_COMPAT_EXT_ATTR, "ext_attr" }, 259 { EXT2F_COMPAT_RESIZE, "resize_inode" }, 260 { EXT2F_COMPAT_DIRHASHINDEX, "dir_index" }, 261 { EXT2F_COMPAT_EXCLUDE_BITMAP, "snapshot_bitmap" }, 262 { EXT2F_COMPAT_SPARSESUPER2, "sparse_super2" } 263 }; 264 265 static const struct ext2_feature ro_compat[] = { 266 { EXT2F_ROCOMPAT_SPARSESUPER, "sparse_super" }, 267 { EXT2F_ROCOMPAT_LARGEFILE, "large_file" }, 268 { EXT2F_ROCOMPAT_BTREE_DIR, "btree_dir" }, 269 { EXT2F_ROCOMPAT_HUGE_FILE, "huge_file" }, 270 { EXT2F_ROCOMPAT_GDT_CSUM, "uninit_groups" }, 271 { EXT2F_ROCOMPAT_DIR_NLINK, "dir_nlink" }, 272 { EXT2F_ROCOMPAT_EXTRA_ISIZE, "extra_isize" }, 273 { EXT2F_ROCOMPAT_HAS_SNAPSHOT, "snapshot" }, 274 { EXT2F_ROCOMPAT_QUOTA, "quota" }, 275 { EXT2F_ROCOMPAT_BIGALLOC, "bigalloc" }, 276 { EXT2F_ROCOMPAT_METADATA_CKSUM, "metadata_csum" }, 277 { EXT2F_ROCOMPAT_REPLICA, "replica" }, 278 { EXT2F_ROCOMPAT_READONLY, "ro" }, 279 { EXT2F_ROCOMPAT_PROJECT, "project" } 280 }; 281 282 static const struct ext2_feature incompat[] = { 283 { EXT2F_INCOMPAT_COMP, "compression" }, 284 { EXT2F_INCOMPAT_FTYPE, "filetype" }, 285 { EXT2F_INCOMPAT_RECOVER, "needs_recovery" }, 286 { EXT2F_INCOMPAT_JOURNAL_DEV, "journal_dev" }, 287 { EXT2F_INCOMPAT_META_BG, "meta_bg" }, 288 { EXT2F_INCOMPAT_EXTENTS, "extents" }, 289 { EXT2F_INCOMPAT_64BIT, "64bit" }, 290 { EXT2F_INCOMPAT_MMP, "mmp" }, 291 { EXT2F_INCOMPAT_FLEX_BG, "flex_bg" }, 292 { EXT2F_INCOMPAT_EA_INODE, "ea_inode" }, 293 { EXT2F_INCOMPAT_DIRDATA, "dirdata" }, 294 { EXT2F_INCOMPAT_CSUM_SEED, "metadata_csum_seed" }, 295 { EXT2F_INCOMPAT_LARGEDIR, "large_dir" }, 296 { EXT2F_INCOMPAT_INLINE_DATA, "inline_data" }, 297 { EXT2F_INCOMPAT_ENCRYPT, "encrypt" } 298 }; 299 300 /* 301 * Features supported in this implementation 302 * 303 * We support the following REV1 features: 304 * - EXT2F_ROCOMPAT_SPARSESUPER 305 * - EXT2F_ROCOMPAT_LARGEFILE 306 * - EXT2F_ROCOMPAT_EXTRA_ISIZE 307 * - EXT2F_INCOMPAT_FTYPE 308 * 309 * We partially (read-only) support the following EXT4 features: 310 * - EXT2F_ROCOMPAT_HUGE_FILE 311 * - EXT2F_INCOMPAT_EXTENTS 312 * 313 * We do not support these EXT4 features but they are irrelevant 314 * for read-only support: 315 * - EXT2F_INCOMPAT_RECOVER 316 * - EXT2F_INCOMPAT_FLEX_BG 317 * - EXT2F_INCOMPAT_META_BG 318 */ 319 #define EXT2F_COMPAT_SUPP EXT2F_COMPAT_DIRHASHINDEX 320 #define EXT2F_ROCOMPAT_SUPP (EXT2F_ROCOMPAT_SPARSESUPER | \ 321 EXT2F_ROCOMPAT_LARGEFILE | \ 322 EXT2F_ROCOMPAT_GDT_CSUM | \ 323 EXT2F_ROCOMPAT_DIR_NLINK | \ 324 EXT2F_ROCOMPAT_HUGE_FILE | \ 325 EXT2F_ROCOMPAT_EXTRA_ISIZE) 326 #define EXT2F_INCOMPAT_SUPP EXT2F_INCOMPAT_FTYPE 327 #define EXT4F_RO_INCOMPAT_SUPP (EXT2F_INCOMPAT_EXTENTS | \ 328 EXT2F_INCOMPAT_RECOVER | \ 329 EXT2F_INCOMPAT_FLEX_BG | \ 330 EXT2F_INCOMPAT_META_BG ) 331 332 /* Assume that user mode programs are passing in an ext2fs superblock, not 333 * a kernel struct super_block. This will allow us to call the feature-test 334 * macros from user land. */ 335 #define EXT2_SB(sb) (sb) 336 337 /* 338 * Feature set definitions 339 */ 340 #define EXT2_HAS_COMPAT_FEATURE(sb,mask) \ 341 ( EXT2_SB(sb)->e2fs->e2fs_features_compat & htole32(mask) ) 342 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask) \ 343 ( EXT2_SB(sb)->e2fs->e2fs_features_rocompat & htole32(mask) ) 344 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask) \ 345 ( EXT2_SB(sb)->e2fs->e2fs_features_incompat & htole32(mask) ) 346 347 /* 348 * File clean flags 349 */ 350 #define E2FS_ISCLEAN 0x0001 /* Unmounted cleanly */ 351 #define E2FS_ERRORS 0x0002 /* Errors detected */ 352 353 /* 354 * Filesystem miscellaneous flags 355 */ 356 #define E2FS_SIGNED_HASH 0x0001 357 #define E2FS_UNSIGNED_HASH 0x0002 358 359 #define EXT2_BG_INODE_UNINIT 0x0001 /* Inode table/bitmap not in use */ 360 #define EXT2_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not in use */ 361 #define EXT2_BG_INODE_ZEROED 0x0004 /* On-disk itable initialized to zero */ 362 363 /* ext2 file system block group descriptor */ 364 365 struct ext2_gd { 366 uint32_t ext2bgd_b_bitmap; /* blocks bitmap block */ 367 uint32_t ext2bgd_i_bitmap; /* inodes bitmap block */ 368 uint32_t ext2bgd_i_tables; /* inodes table block */ 369 uint16_t ext2bgd_nbfree; /* number of free blocks */ 370 uint16_t ext2bgd_nifree; /* number of free inodes */ 371 uint16_t ext2bgd_ndirs; /* number of directories */ 372 uint16_t ext4bgd_flags; /* block group flags */ 373 uint32_t ext4bgd_x_bitmap; /* snapshot exclusion bitmap loc. */ 374 uint16_t ext4bgd_b_bmap_csum; /* block bitmap checksum */ 375 uint16_t ext4bgd_i_bmap_csum; /* inode bitmap checksum */ 376 uint16_t ext4bgd_i_unused; /* unused inode count */ 377 uint16_t ext4bgd_csum; /* group descriptor checksum */ 378 }; 379 380 /* EXT2FS metadata is stored in little-endian byte order. These macros 381 * help reading it. 382 */ 383 384 #define e2fs_cgload(old, new, size) memcpy((new), (old), (size)); 385 #define e2fs_cgsave(old, new, size) memcpy((new), (old), (size)); 386 387 /* 388 * Macro-instructions used to manage several block sizes 389 */ 390 #define EXT2_MIN_BLOCK_LOG_SIZE 10 391 #define EXT2_BLOCK_SIZE(s) ((s)->e2fs_bsize) 392 #define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof(uint32_t)) 393 #define EXT2_INODE_SIZE(s) (EXT2_SB(s)->e2fs_isize) 394 395 /* 396 * Macro-instructions used to manage fragments 397 */ 398 #define EXT2_MIN_FRAG_SIZE 1024 399 #define EXT2_MAX_FRAG_SIZE 4096 400 #define EXT2_MIN_FRAG_LOG_SIZE 10 401 #define EXT2_FRAG_SIZE(s) (EXT2_SB(s)->e2fs_fsize) 402 #define EXT2_FRAGS_PER_BLOCK(s) (EXT2_SB(s)->e2fs_fpb) 403 404 /* 405 * Macro-instructions used to manage group descriptors 406 */ 407 #define EXT2_BLOCKS_PER_GROUP(s) (EXT2_SB(s)->e2fs_bpg) 408 409 #endif /* !_FS_EXT2FS_EXT2FS_H_ */ 410