busybox/include/bb_e2fs_defs.h
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   1/* vi: set sw=4 ts=4: */
   2/*
   3 *  linux/include/linux/ext2_fs.h
   4 *
   5 * Copyright (C) 1992, 1993, 1994, 1995
   6 * Remy Card (card@masi.ibp.fr)
   7 * Laboratoire MASI - Institut Blaise Pascal
   8 * Universite Pierre et Marie Curie (Paris VI)
   9 *
  10 * Copyright (C) 1991, 1992  Linus Torvalds
  11 */
  12
  13#ifndef LINUX_EXT2_FS_H
  14#define LINUX_EXT2_FS_H 1
  15
  16/*
  17 * Special inode numbers
  18 */
  19#define EXT2_BAD_INO             1      /* Bad blocks inode */
  20#define EXT2_ROOT_INO            2      /* Root inode */
  21#define EXT2_ACL_IDX_INO         3      /* ACL inode */
  22#define EXT2_ACL_DATA_INO        4      /* ACL inode */
  23#define EXT2_BOOT_LOADER_INO     5      /* Boot loader inode */
  24#define EXT2_UNDEL_DIR_INO       6      /* Undelete directory inode */
  25#define EXT2_RESIZE_INO          7      /* Reserved group descriptors inode */
  26#define EXT2_JOURNAL_INO         8      /* Journal inode */
  27
  28/* First non-reserved inode for old ext2 filesystems */
  29#define EXT2_GOOD_OLD_FIRST_INO 11
  30
  31/*
  32 * The second extended file system magic number
  33 */
  34#define EXT2_SUPER_MAGIC        0xEF53
  35
  36/* Assume that user mode programs are passing in an ext2fs superblock, not
  37 * a kernel struct super_block.  This will allow us to call the feature-test
  38 * macros from user land. */
  39#define EXT2_SB(sb)     (sb)
  40
  41/*
  42 * Maximal count of links to a file
  43 */
  44#define EXT2_LINK_MAX           32000
  45
  46/*
  47 * Macro-instructions used to manage several block sizes
  48 */
  49#define EXT2_MIN_BLOCK_LOG_SIZE         10      /* 1024 */
  50#define EXT2_MAX_BLOCK_LOG_SIZE         16      /* 65536 */
  51#define EXT2_MIN_BLOCK_SIZE     (1 << EXT2_MIN_BLOCK_LOG_SIZE)
  52#define EXT2_MAX_BLOCK_SIZE     (1 << EXT2_MAX_BLOCK_LOG_SIZE)
  53#define EXT2_BLOCK_SIZE(s)      (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
  54#define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
  55#define EXT2_INODE_SIZE(s)      (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
  56                                 EXT2_GOOD_OLD_INODE_SIZE : (s)->s_inode_size)
  57#define EXT2_FIRST_INO(s)       (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
  58                                 EXT2_GOOD_OLD_FIRST_INO : (s)->s_first_ino)
  59#define EXT2_ADDR_PER_BLOCK(s)  (EXT2_BLOCK_SIZE(s) / sizeof(uint32_t))
  60
  61/*
  62 * Macro-instructions used to manage fragments
  63 */
  64#define EXT2_MIN_FRAG_SIZE              EXT2_MIN_BLOCK_SIZE
  65#define EXT2_MAX_FRAG_SIZE              EXT2_MAX_BLOCK_SIZE
  66#define EXT2_MIN_FRAG_LOG_SIZE          EXT2_MIN_BLOCK_LOG_SIZE
  67#define EXT2_FRAG_SIZE(s)               (EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
  68#define EXT2_FRAGS_PER_BLOCK(s)         (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
  69
  70/*
  71 * ACL structures
  72 */
  73struct ext2_acl_header {        /* Header of Access Control Lists */
  74        uint32_t        aclh_size;
  75        uint32_t        aclh_file_count;
  76        uint32_t        aclh_acle_count;
  77        uint32_t        aclh_first_acle;
  78};
  79
  80struct ext2_acl_entry { /* Access Control List Entry */
  81        uint32_t        acle_size;
  82        uint16_t        acle_perms;     /* Access permissions */
  83        uint16_t        acle_type;      /* Type of entry */
  84        uint16_t        acle_tag;       /* User or group identity */
  85        uint16_t        acle_pad1;
  86        uint32_t        acle_next;      /* Pointer on next entry for the */
  87                                        /* same inode or on next free entry */
  88};
  89
  90/*
  91 * Structure of a blocks group descriptor
  92 */
  93struct ext2_group_desc {
  94        uint32_t        bg_block_bitmap;        /* Blocks bitmap block */
  95        uint32_t        bg_inode_bitmap;        /* Inodes bitmap block */
  96        uint32_t        bg_inode_table;         /* Inodes table block */
  97        uint16_t        bg_free_blocks_count;   /* Free blocks count */
  98        uint16_t        bg_free_inodes_count;   /* Free inodes count */
  99        uint16_t        bg_used_dirs_count;     /* Directories count */
 100        uint16_t        bg_pad;
 101        uint32_t        bg_reserved[3];
 102};
 103
 104/*
 105 * Data structures used by the directory indexing feature
 106 *
 107 * Note: all of the multibyte integer fields are little endian.
 108 */
 109
 110/*
 111 * Note: dx_root_info is laid out so that if it should somehow get
 112 * overlaid by a dirent the two low bits of the hash version will be
 113 * zero.  Therefore, the hash version mod 4 should never be 0.
 114 * Sincerely, the paranoia department.
 115 */
 116struct ext2_dx_root_info {
 117        uint32_t        reserved_zero;
 118        uint8_t         hash_version; /* 0 now, 1 at release */
 119        uint8_t         info_length; /* 8 */
 120        uint8_t         indirect_levels;
 121        uint8_t         unused_flags;
 122};
 123
 124#define EXT2_HASH_LEGACY        0
 125#define EXT2_HASH_HALF_MD4      1
 126#define EXT2_HASH_TEA           2
 127
 128#define EXT2_HASH_FLAG_INCOMPAT 0x1
 129
 130struct ext2_dx_entry {
 131        uint32_t hash;
 132        uint32_t block;
 133};
 134
 135struct ext2_dx_countlimit {
 136        uint16_t limit;
 137        uint16_t count;
 138};
 139
 140
 141/*
 142 * Macro-instructions used to manage group descriptors
 143 */
 144#define EXT2_BLOCKS_PER_GROUP(s)        (EXT2_SB(s)->s_blocks_per_group)
 145#define EXT2_INODES_PER_GROUP(s)        (EXT2_SB(s)->s_inodes_per_group)
 146#define EXT2_INODES_PER_BLOCK(s)        (EXT2_BLOCK_SIZE(s)/EXT2_INODE_SIZE(s))
 147/* limits imposed by 16-bit value gd_free_{blocks,inode}_count */
 148#define EXT2_MAX_BLOCKS_PER_GROUP(s)    ((1 << 16) - 8)
 149#define EXT2_MAX_INODES_PER_GROUP(s)    ((1 << 16) - EXT2_INODES_PER_BLOCK(s))
 150#define EXT2_DESC_PER_BLOCK(s)          (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
 151
 152/*
 153 * Constants relative to the data blocks
 154 */
 155#define EXT2_NDIR_BLOCKS                12
 156#define EXT2_IND_BLOCK                  EXT2_NDIR_BLOCKS
 157#define EXT2_DIND_BLOCK                 (EXT2_IND_BLOCK + 1)
 158#define EXT2_TIND_BLOCK                 (EXT2_DIND_BLOCK + 1)
 159#define EXT2_N_BLOCKS                   (EXT2_TIND_BLOCK + 1)
 160
 161/*
 162 * Inode flags
 163 */
 164#define EXT2_SECRM_FL                   0x00000001 /* Secure deletion */
 165#define EXT2_UNRM_FL                    0x00000002 /* Undelete */
 166#define EXT2_COMPR_FL                   0x00000004 /* Compress file */
 167#define EXT2_SYNC_FL                    0x00000008 /* Synchronous updates */
 168#define EXT2_IMMUTABLE_FL               0x00000010 /* Immutable file */
 169#define EXT2_APPEND_FL                  0x00000020 /* writes to file may only append */
 170#define EXT2_NODUMP_FL                  0x00000040 /* do not dump file */
 171#define EXT2_NOATIME_FL                 0x00000080 /* do not update atime */
 172/* Reserved for compression usage... */
 173#define EXT2_DIRTY_FL                   0x00000100
 174#define EXT2_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 175#define EXT2_NOCOMPR_FL                 0x00000400 /* Access raw compressed data */
 176#define EXT2_ECOMPR_FL                  0x00000800 /* Compression error */
 177/* End compression flags --- maybe not all used */
 178#define EXT2_BTREE_FL                   0x00001000 /* btree format dir */
 179#define EXT2_INDEX_FL                   0x00001000 /* hash-indexed directory */
 180#define EXT2_IMAGIC_FL                  0x00002000
 181#define EXT3_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
 182#define EXT2_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
 183#define EXT2_DIRSYNC_FL                 0x00010000 /* Synchronous directory modifications */
 184#define EXT2_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
 185#define EXT2_EXTENT_FL                  0x00080000 /* Extents */
 186#define EXT2_VERITY_FL                  0x00100000
 187#define EXT2_NOCOW_FL                   0x00800000 /* Do not cow file */
 188#define EXT2_INLINE_DATA_FL             0x10000000
 189#define EXT2_PROJINHERIT_FL             0x20000000
 190#define EXT2_CASEFOLD_FL                0x40000000
 191
 192/*
 193 * ioctl commands
 194 */
 195#define EXT2_IOC_GETFLAGS               _IOR('f', 1, long)
 196#define EXT2_IOC_SETFLAGS               _IOW('f', 2, long)
 197#define EXT2_IOC_GETVERSION             _IOR('v', 1, long)
 198#define EXT2_IOC_SETVERSION             _IOW('v', 2, long)
 199//NB: despite "long" in defs above, these ioctls use an _int_!
 200//passing them a pointer to long will read/write only int-sized data!
 201struct ext2_fsxattr {
 202        uint32_t        fsx_xflags;     /* xflags field value (get/set) */
 203        uint32_t        fsx_extsize;    /* extsize field value (get/set)*/
 204        uint32_t        fsx_nextents;   /* nextents field value (get)   */
 205        uint32_t        fsx_projid;     /* project identifier (get/set) */
 206        uint32_t        fsx_cowextsize; /* CoW extsize field value (get/set)*/
 207        unsigned char   fsx_pad[8];
 208};
 209#define EXT2_IOC_FSGETXATTR             _IOR('X', 31, struct ext2_fsxattr)
 210#define EXT2_IOC_FSSETXATTR             _IOW('X', 32, struct ext2_fsxattr)
 211
 212/*
 213 * Structure of an inode on the disk
 214 */
 215struct ext2_inode {
 216        uint16_t        i_mode;         /* File mode */
 217        uint16_t        i_uid;          /* Low 16 bits of Owner Uid */
 218        uint32_t        i_size;         /* Size in bytes */
 219        uint32_t        i_atime;        /* Access time */
 220        uint32_t        i_ctime;        /* Creation time */
 221        uint32_t        i_mtime;        /* Modification time */
 222        uint32_t        i_dtime;        /* Deletion Time */
 223        uint16_t        i_gid;          /* Low 16 bits of Group Id */
 224        uint16_t        i_links_count;  /* Links count */
 225        uint32_t        i_blocks;       /* Blocks count */
 226        uint32_t        i_flags;        /* File flags */
 227        union {
 228                struct {
 229                        uint32_t  l_i_reserved1;
 230                } linux1;
 231                struct {
 232                        uint32_t  h_i_translator;
 233                } hurd1;
 234                struct {
 235                        uint32_t  m_i_reserved1;
 236                } masix1;
 237        } osd1;                         /* OS dependent 1 */
 238        uint32_t        i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
 239        uint32_t        i_generation;   /* File version (for NFS) */
 240        uint32_t        i_file_acl;     /* File ACL */
 241        uint32_t        i_dir_acl;      /* Directory ACL */
 242        uint32_t        i_faddr;        /* Fragment address */
 243        union {
 244                struct {
 245                        uint8_t         l_i_frag;       /* Fragment number */
 246                        uint8_t         l_i_fsize;      /* Fragment size */
 247                        uint16_t        i_pad1;
 248                        uint16_t        l_i_uid_high;   /* these 2 fields    */
 249                        uint16_t        l_i_gid_high;   /* were reserved2[0] */
 250                        uint32_t        l_i_reserved2;
 251                } linux2;
 252                struct {
 253                        uint8_t         h_i_frag;       /* Fragment number */
 254                        uint8_t         h_i_fsize;      /* Fragment size */
 255                        uint16_t        h_i_mode_high;
 256                        uint16_t        h_i_uid_high;
 257                        uint16_t        h_i_gid_high;
 258                        uint32_t        h_i_author;
 259                } hurd2;
 260                struct {
 261                        uint8_t         m_i_frag;       /* Fragment number */
 262                        uint8_t         m_i_fsize;      /* Fragment size */
 263                        uint16_t        m_pad1;
 264                        uint32_t        m_i_reserved2[2];
 265                } masix2;
 266        } osd2;                         /* OS dependent 2 */
 267};
 268
 269/*
 270 * Permanent part of an large inode on the disk
 271 */
 272struct ext2_inode_large {
 273        uint16_t        i_mode;         /* File mode */
 274        uint16_t        i_uid;          /* Low 16 bits of Owner Uid */
 275        uint32_t        i_size;         /* Size in bytes */
 276        uint32_t        i_atime;        /* Access time */
 277        uint32_t        i_ctime;        /* Creation time */
 278        uint32_t        i_mtime;        /* Modification time */
 279        uint32_t        i_dtime;        /* Deletion Time */
 280        uint16_t        i_gid;          /* Low 16 bits of Group Id */
 281        uint16_t        i_links_count;  /* Links count */
 282        uint32_t        i_blocks;       /* Blocks count */
 283        uint32_t        i_flags;        /* File flags */
 284        union {
 285                struct {
 286                        uint32_t  l_i_reserved1;
 287                } linux1;
 288                struct {
 289                        uint32_t  h_i_translator;
 290                } hurd1;
 291                struct {
 292                        uint32_t  m_i_reserved1;
 293                } masix1;
 294        } osd1;                         /* OS dependent 1 */
 295        uint32_t        i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
 296        uint32_t        i_generation;   /* File version (for NFS) */
 297        uint32_t        i_file_acl;     /* File ACL */
 298        uint32_t        i_dir_acl;      /* Directory ACL */
 299        uint32_t        i_faddr;        /* Fragment address */
 300        union {
 301                struct {
 302                        uint8_t         l_i_frag;       /* Fragment number */
 303                        uint8_t         l_i_fsize;      /* Fragment size */
 304                        uint16_t        i_pad1;
 305                        uint16_t        l_i_uid_high;   /* these 2 fields    */
 306                        uint16_t        l_i_gid_high;   /* were reserved2[0] */
 307                        uint32_t        l_i_reserved2;
 308                } linux2;
 309                struct {
 310                        uint8_t         h_i_frag;       /* Fragment number */
 311                        uint8_t         h_i_fsize;      /* Fragment size */
 312                        uint16_t        h_i_mode_high;
 313                        uint16_t        h_i_uid_high;
 314                        uint16_t        h_i_gid_high;
 315                        uint32_t        h_i_author;
 316                } hurd2;
 317                struct {
 318                        uint8_t         m_i_frag;       /* Fragment number */
 319                        uint8_t         m_i_fsize;      /* Fragment size */
 320                        uint16_t        m_pad1;
 321                        uint32_t        m_i_reserved2[2];
 322                } masix2;
 323        } osd2;                         /* OS dependent 2 */
 324        uint16_t        i_extra_isize;
 325        uint16_t        i_pad1;
 326};
 327
 328#define i_size_high     i_dir_acl
 329
 330/*
 331 * File system states
 332 */
 333#define EXT2_VALID_FS                   0x0001  /* Unmounted cleanly */
 334#define EXT2_ERROR_FS                   0x0002  /* Errors detected */
 335
 336/*
 337 * Mount flags
 338 */
 339#define EXT2_MOUNT_CHECK                0x0001  /* Do mount-time checks */
 340#define EXT2_MOUNT_GRPID                0x0004  /* Create files with directory's group */
 341#define EXT2_MOUNT_DEBUG                0x0008  /* Some debugging messages */
 342#define EXT2_MOUNT_ERRORS_CONT          0x0010  /* Continue on errors */
 343#define EXT2_MOUNT_ERRORS_RO            0x0020  /* Remount fs ro on errors */
 344#define EXT2_MOUNT_ERRORS_PANIC         0x0040  /* Panic on errors */
 345#define EXT2_MOUNT_MINIX_DF             0x0080  /* Mimics the Minix statfs */
 346#define EXT2_MOUNT_NO_UID32             0x0200  /* Disable 32-bit UIDs */
 347
 348#define clear_opt(o, opt)               o &= ~EXT2_MOUNT_##opt
 349#define set_opt(o, opt)                 o |= EXT2_MOUNT_##opt
 350#define test_opt(sb, opt)               (EXT2_SB(sb)->s_mount_opt & \
 351                                         EXT2_MOUNT_##opt)
 352/*
 353 * Maximal mount counts between two filesystem checks
 354 */
 355#define EXT2_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
 356#define EXT2_DFL_CHECKINTERVAL          0       /* Don't use interval check */
 357
 358/*
 359 * Behaviour when detecting errors
 360 */
 361#define EXT2_ERRORS_CONTINUE            1       /* Continue execution */
 362#define EXT2_ERRORS_RO                  2       /* Remount fs read-only */
 363#define EXT2_ERRORS_PANIC               3       /* Panic */
 364#define EXT2_ERRORS_DEFAULT             EXT2_ERRORS_CONTINUE
 365
 366/*
 367 * Structure of the super block
 368 */
 369struct ext2_super_block {
 370        uint32_t        s_inodes_count;         /* Inodes count */
 371        uint32_t        s_blocks_count;         /* Blocks count */
 372        uint32_t        s_r_blocks_count;       /* Reserved blocks count */
 373        uint32_t        s_free_blocks_count;    /* Free blocks count */
 374        uint32_t        s_free_inodes_count;    /* Free inodes count */
 375        uint32_t        s_first_data_block;     /* First Data Block */
 376        uint32_t        s_log_block_size;       /* Block size */
 377        int32_t         s_log_frag_size;        /* Fragment size */
 378        uint32_t        s_blocks_per_group;     /* # Blocks per group */
 379        uint32_t        s_frags_per_group;      /* # Fragments per group */
 380        uint32_t        s_inodes_per_group;     /* # Inodes per group */
 381        uint32_t        s_mtime;                /* Mount time */
 382        uint32_t        s_wtime;                /* Write time */
 383        uint16_t        s_mnt_count;            /* Mount count */
 384        int16_t         s_max_mnt_count;        /* Maximal mount count */
 385        uint16_t        s_magic;                /* Magic signature */
 386        uint16_t        s_state;                /* File system state */
 387        uint16_t        s_errors;               /* Behaviour when detecting errors */
 388        uint16_t        s_minor_rev_level;      /* minor revision level */
 389        uint32_t        s_lastcheck;            /* time of last check */
 390        uint32_t        s_checkinterval;        /* max. time between checks */
 391        uint32_t        s_creator_os;           /* OS */
 392        uint32_t        s_rev_level;            /* Revision level */
 393        uint16_t        s_def_resuid;           /* Default uid for reserved blocks */
 394        uint16_t        s_def_resgid;           /* Default gid for reserved blocks */
 395        /*
 396         * These fields are for EXT2_DYNAMIC_REV superblocks only.
 397         *
 398         * Note: the difference between the compatible feature set and
 399         * the incompatible feature set is that if there is a bit set
 400         * in the incompatible feature set that the kernel doesn't
 401         * know about, it should refuse to mount the filesystem.
 402         *
 403         * e2fsck's requirements are more strict; if it doesn't know
 404         * about a feature in either the compatible or incompatible
 405         * feature set, it must abort and not try to meddle with
 406         * things it doesn't understand...
 407         */
 408        uint32_t        s_first_ino;            /* First non-reserved inode */
 409        uint16_t        s_inode_size;           /* size of inode structure */
 410        uint16_t        s_block_group_nr;       /* block group # of this superblock */
 411        uint32_t        s_feature_compat;       /* compatible feature set */
 412        uint32_t        s_feature_incompat;     /* incompatible feature set */
 413        uint32_t        s_feature_ro_compat;    /* readonly-compatible feature set */
 414        uint8_t         s_uuid[16];             /* 128-bit uuid for volume */
 415        char            s_volume_name[16];      /* volume name */
 416        char            s_last_mounted[64];     /* directory where last mounted */
 417        uint32_t        s_algorithm_usage_bitmap; /* For compression */
 418        /*
 419         * Performance hints.  Directory preallocation should only
 420         * happen if the EXT2_FEATURE_COMPAT_DIR_PREALLOC flag is on.
 421         */
 422        uint8_t         s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
 423        uint8_t         s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
 424        uint16_t        s_reserved_gdt_blocks;  /* Per group table for online growth */
 425        /*
 426         * Journaling support valid if EXT2_FEATURE_COMPAT_HAS_JOURNAL set.
 427         */
 428/*D0*/  uint8_t         s_journal_uuid[16];     /* uuid of journal superblock */
 429/*E0*/  uint32_t        s_journal_inum;         /* inode number of journal file */
 430        uint32_t        s_journal_dev;          /* device number of journal file */
 431        uint32_t        s_last_orphan;          /* start of list of inodes to delete */
 432        uint32_t        s_hash_seed[4];         /* HTREE hash seed */
 433        uint8_t         s_def_hash_version;     /* Default hash version to use */
 434        uint8_t         s_jnl_backup_type;      /* Default type of journal backup */
 435        uint16_t        s_reserved_word_pad;
 436/*100*/ uint32_t        s_default_mount_opts;
 437        uint32_t        s_first_meta_bg;        /* First metablock group */
 438        /* ext3 additions */
 439        uint32_t        s_mkfs_time;            /* When the filesystem was created */
 440        uint32_t        s_jnl_blocks[17];       /* Backup of the journal inode */
 441        /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
 442/*150*/ uint32_t        s_blocks_count_hi;      /* Blocks count */
 443        uint32_t        s_r_blocks_count_hi;    /* Reserved blocks count */
 444        uint32_t        s_free_blocks_count_hi; /* Free blocks count */
 445        uint16_t        s_min_extra_isize;      /* All inodes have at least # bytes */
 446        uint16_t        s_want_extra_isize;     /* New inodes should reserve # bytes */
 447        uint32_t        s_flags;                /* Miscellaneous flags */
 448        uint16_t        s_raid_stride;          /* RAID stride */
 449        uint16_t        s_mmp_interval;         /* # seconds to wait in MMP checking */
 450        uint64_t        s_mmp_block;            /* Block for multi-mount protection */
 451        uint32_t        s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
 452        uint8_t         s_log_groups_per_flex;  /* FLEX_BG group size */
 453        uint8_t         s_reserved_char_pad2;
 454        uint16_t        s_reserved_pad;
 455        uint32_t        s_reserved[162];        /* Padding to the end of the block */
 456};
 457struct BUG_ext2_super_block {
 458        char bug[sizeof(struct ext2_super_block) == 1024 ? 1 : -1];
 459};
 460
 461/*
 462 * Codes for operating systems
 463 */
 464#define EXT2_OS_LINUX           0
 465#define EXT2_OS_HURD            1
 466#define EXT2_OS_MASIX           2
 467#define EXT2_OS_FREEBSD         3
 468#define EXT2_OS_LITES           4
 469
 470/*
 471 * Revision levels
 472 */
 473#define EXT2_GOOD_OLD_REV       0       /* The good old (original) format */
 474#define EXT2_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
 475
 476#define EXT2_CURRENT_REV        EXT2_GOOD_OLD_REV
 477#define EXT2_MAX_SUPP_REV       EXT2_DYNAMIC_REV
 478
 479#define EXT2_GOOD_OLD_INODE_SIZE 128
 480
 481/*
 482 * Journal inode backup types
 483 */
 484#define EXT3_JNL_BACKUP_BLOCKS  1
 485
 486/*
 487 * Feature set definitions
 488 */
 489
 490#define EXT2_HAS_COMPAT_FEATURE(sb,mask)                        \
 491        ( EXT2_SB(sb)->s_feature_compat & (mask) )
 492#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
 493        ( EXT2_SB(sb)->s_feature_ro_compat & (mask) )
 494#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask)                      \
 495        ( EXT2_SB(sb)->s_feature_incompat & (mask) )
 496
 497/* for s_feature_compat */
 498#define EXT2_FEATURE_COMPAT_DIR_PREALLOC        0x0001
 499#define EXT2_FEATURE_COMPAT_IMAGIC_INODES       0x0002
 500#define EXT3_FEATURE_COMPAT_HAS_JOURNAL         0x0004
 501#define EXT2_FEATURE_COMPAT_EXT_ATTR            0x0008
 502#define EXT2_FEATURE_COMPAT_RESIZE_INO          0x0010
 503#define EXT2_FEATURE_COMPAT_DIR_INDEX           0x0020
 504
 505/* for s_feature_ro_compat */
 506#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
 507#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
 508#define EXT2_FEATURE_RO_COMPAT_BTREE_DIR        0x0004 /* not used */
 509#define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
 510#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
 511#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
 512#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
 513
 514/* for s_feature_incompat */
 515#define EXT2_FEATURE_INCOMPAT_COMPRESSION       0x0001
 516#define EXT2_FEATURE_INCOMPAT_FILETYPE          0x0002
 517#define EXT3_FEATURE_INCOMPAT_RECOVER           0x0004
 518#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008
 519#define EXT2_FEATURE_INCOMPAT_META_BG           0x0010
 520#define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040
 521#define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
 522#define EXT4_FEATURE_INCOMPAT_MMP               0x0100
 523#define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
 524
 525
 526#define EXT2_FEATURE_COMPAT_SUPP        0
 527#define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
 528                                         EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
 529                                         EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
 530#define EXT2_FEATURE_INCOMPAT_SUPP      (EXT2_FEATURE_INCOMPAT_FILETYPE| \
 531                                         EXT2_FEATURE_INCOMPAT_META_BG)
 532#define EXT2_FEATURE_INCOMPAT_UNSUPPORTED       (~EXT2_FEATURE_INCOMPAT_SUPP)
 533#define EXT2_FEATURE_RO_COMPAT_UNSUPPORTED      (~EXT2_FEATURE_RO_COMPAT_SUPP)
 534
 535#define EXT3_FEATURE_RO_COMPAT_SUPP     (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
 536                                         EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
 537                                         EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
 538#define EXT3_FEATURE_INCOMPAT_SUPP      (EXT2_FEATURE_INCOMPAT_FILETYPE| \
 539                                         EXT3_FEATURE_INCOMPAT_RECOVER| \
 540                                         EXT2_FEATURE_INCOMPAT_META_BG)
 541#define EXT3_FEATURE_INCOMPAT_UNSUPPORTED       (~EXT3_FEATURE_INCOMPAT_SUPP)
 542#define EXT3_FEATURE_RO_COMPAT_UNSUPPORTED      (~EXT3_FEATURE_RO_COMPAT_SUPP)
 543
 544
 545/*
 546 * Default values for user and/or group using reserved blocks
 547 */
 548#define EXT2_DEF_RESUID         0
 549#define EXT2_DEF_RESGID         0
 550
 551/*
 552 * Default mount options
 553 */
 554#define EXT2_DEFM_DEBUG         0x0001
 555#define EXT2_DEFM_BSDGROUPS     0x0002
 556#define EXT2_DEFM_XATTR_USER    0x0004
 557#define EXT2_DEFM_ACL           0x0008
 558#define EXT2_DEFM_UID16         0x0010
 559#define EXT3_DEFM_JMODE         0x0060
 560#define EXT3_DEFM_JMODE_DATA    0x0020
 561#define EXT3_DEFM_JMODE_ORDERED 0x0040
 562#define EXT3_DEFM_JMODE_WBACK   0x0060
 563
 564/*
 565 * Structure of a directory entry
 566 */
 567#define EXT2_NAME_LEN 255
 568
 569struct ext2_dir_entry {
 570        uint32_t        inode;                  /* Inode number */
 571        uint16_t        rec_len;                /* Directory entry length */
 572        uint16_t        name_len;               /* Name length */
 573        char            name[EXT2_NAME_LEN];    /* File name */
 574};
 575
 576/*
 577 * The new version of the directory entry.  Since EXT2 structures are
 578 * stored in intel byte order, and the name_len field could never be
 579 * bigger than 255 chars, it's safe to reclaim the extra byte for the
 580 * file_type field.
 581 */
 582struct ext2_dir_entry_2 {
 583        uint32_t        inode;                  /* Inode number */
 584        uint16_t        rec_len;                /* Directory entry length */
 585        uint8_t         name_len;               /* Name length */
 586        uint8_t         file_type;
 587        char            name[EXT2_NAME_LEN];    /* File name */
 588};
 589
 590/*
 591 * Ext2 directory file types.  Only the low 3 bits are used.  The
 592 * other bits are reserved for now.
 593 */
 594#define EXT2_FT_UNKNOWN         0
 595#define EXT2_FT_REG_FILE        1
 596#define EXT2_FT_DIR             2
 597#define EXT2_FT_CHRDEV          3
 598#define EXT2_FT_BLKDEV          4
 599#define EXT2_FT_FIFO            5
 600#define EXT2_FT_SOCK            6
 601#define EXT2_FT_SYMLINK         7
 602
 603#define EXT2_FT_MAX             8
 604
 605/*
 606 * EXT2_DIR_PAD defines the directory entries boundaries
 607 *
 608 * NOTE: It must be a multiple of 4
 609 */
 610#define EXT2_DIR_PAD                    4
 611#define EXT2_DIR_ROUND                  (EXT2_DIR_PAD - 1)
 612#define EXT2_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT2_DIR_ROUND) & \
 613                                         ~EXT2_DIR_ROUND)
 614
 615#endif
 616