lwext4/ext4_types.h

   1 /*
   2  * Copyright (c) 2013 Grzegorz Kostka (kostka.grzegorz@gmail.com)
   3  *
   4  *
   5  * HelenOS:
   6  * Copyright (c) 2012 Martin Sucha
   7  * Copyright (c) 2012 Frantisek Princ
   8  * All rights reserved.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  *
  14  * - Redistributions of source code must retain the above copyright
  15  *   notice, this list of conditions and the following disclaimer.
  16  * - Redistributions in binary form must reproduce the above copyright
  17  *   notice, this list of conditions and the following disclaimer in the
  18  *   documentation and/or other materials provided with the distribution.
  19  * - The name of the author may not be used to endorse or promote products
  20  *   derived from this software without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 /** @addtogroup lwext4
  35  * @{
  36  */
  37 /**
  38  * @file  ext4_types.h
  39  * @brief Ext4 data structure definitions.
  40  */
  41
  42 #ifndef EXT4_TYPES_H_
  43 #define EXT4_TYPES_H_
  44
  45 #include "ext4_config.h"
  46 #include "ext4_blockdev.h"
  47
  48 #include <stdint.h>
  49
  50 /*
  51  * Structure of the super block
  52  */
  53 struct ext4_sblock {
  54     uint32_t inodes_count;             /* I-nodes count */
  55     uint32_t blocks_count_lo;          /* Blocks count */
  56     uint32_t reserved_blocks_count_lo; /* Reserved blocks count */
  57     uint32_t free_blocks_count_lo;     /* Free blocks count */
  58     uint32_t free_inodes_count;        /* Free inodes count */
  59     uint32_t first_data_block;         /* First Data Block */
  60     uint32_t log_block_size;           /* Block size */
  61     uint32_t log_cluster_size;         /* Obsoleted fragment size */
  62     uint32_t blocks_per_group;         /* Number of blocks per group */
  63     uint32_t frags_per_group;          /* Obsoleted fragments per group */
  64     uint32_t inodes_per_group;         /* Number of inodes per group */
  65     uint32_t mount_time;               /* Mount time */
  66     uint32_t write_time;               /* Write time */
  67     uint16_t mount_count;              /* Mount count */
  68     uint16_t max_mount_count;          /* Maximal mount count */
  69     uint16_t magic;                    /* Magic signature */
  70     uint16_t state;                    /* File system state */
  71     uint16_t errors;                   /* Behaviour when detecting errors */
  72     uint16_t minor_rev_level;          /* Minor revision level */
  73     uint32_t last_check_time;          /* Time of last check */
  74     uint32_t check_interval;           /* Maximum time between checks */
  75     uint32_t creator_os;               /* Creator OS */
  76     uint32_t rev_level;                /* Revision level */
  77     uint16_t def_resuid;               /* Default uid for reserved blocks */
  78     uint16_t def_resgid;               /* Default gid for reserved blocks */
  79
  80     /* Fields for EXT4_DYNAMIC_REV superblocks only. */
  81     uint32_t first_inode;            /* First non-reserved inode */
  82     uint16_t inode_size;             /* Size of inode structure */
  83     uint16_t block_group_index;      /* Block group index of this superblock */
  84     uint32_t features_compatible;    /* Compatible feature set */
  85     uint32_t features_incompatible;  /* Incompatible feature set */
  86     uint32_t features_read_only;     /* Readonly-compatible feature set */
  87     uint8_t uuid[16];                /* 128-bit uuid for volume */
  88     char volume_name[16];            /* Volume name */
  89     char last_mounted[64];           /* Directory where last mounted */
  90     uint32_t algorithm_usage_bitmap; /* For compression */
  91
  92     /*
  93      * Performance hints. Directory preallocation should only
  94      * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
  95      */
  96     uint8_t s_prealloc_blocks;      /* Number of blocks to try to preallocate */
  97     uint8_t s_prealloc_dir_blocks;  /* Number to preallocate for dirs */
  98     uint16_t s_reserved_gdt_blocks; /* Per group desc for online growth */
  99
 100     /*
 101      * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
 102      */
 103     uint8_t journal_uuid[16];      /* UUID of journal superblock */
 104     uint32_t journal_inode_number; /* Inode number of journal file */
 105     uint32_t journal_dev;          /* Device number of journal file */
 106     uint32_t last_orphan;          /* Head of list of inodes to delete */
 107     uint32_t hash_seed[4];         /* HTREE hash seed */
 108     uint8_t default_hash_version;  /* Default hash version to use */
 109     uint8_t journal_backup_type;
 110     uint16_t desc_size;          /* Size of group descriptor */
 111     uint32_t default_mount_opts; /* Default mount options */
 112     uint32_t first_meta_bg;      /* First metablock block group */
 113     uint32_t mkfs_time;          /* When the filesystem was created */
 114     uint32_t journal_blocks[17]; /* Backup of the journal inode */
 115
 116     /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
 117     uint32_t blocks_count_hi;          /* Blocks count */
 118     uint32_t reserved_blocks_count_hi; /* Reserved blocks count */
 119     uint32_t free_blocks_count_hi;     /* Free blocks count */
 120     uint16_t min_extra_isize;          /* All inodes have at least # bytes */
 121     uint16_t want_extra_isize;         /* New inodes should reserve # bytes */
 122     uint32_t flags;                    /* Miscellaneous flags */
 123     uint16_t raid_stride;              /* RAID stride */
 124     uint16_t mmp_interval;             /* # seconds to wait in MMP checking */
 125     uint64_t mmp_block;                /* Block for multi-mount protection */
 126     uint32_t raid_stripe_width;  /* Blocks on all data disks (N * stride) */
 127     uint8_t log_groups_per_flex; /* FLEX_BG group size */
 128     uint8_t reserved_char_pad;
 129     uint16_t reserved_pad;
 130     uint64_t kbytes_written;          /* Number of lifetime kilobytes written */
 131     uint32_t snapshot_inum;           /* I-node number of active snapshot */
 132     uint32_t snapshot_id;             /* Sequential ID of active snapshot */
 133     uint64_t snapshot_r_blocks_count; /* Reserved blocks for active snapshot's
 134                                          future use */
 135     uint32_t snapshot_list; /* I-node number of the head of the on-disk snapshot
 136                                list */
 137     uint32_t error_count;   /* Number of file system errors */
 138     uint32_t first_error_time;    /* First time an error happened */
 139     uint32_t first_error_ino;     /* I-node involved in first error */
 140     uint64_t first_error_block;   /* Block involved of first error */
 141     uint8_t first_error_func[32]; /* Function where the error happened */
 142     uint32_t first_error_line;    /* Line number where error happened */
 143     uint32_t last_error_time;     /* Most recent time of an error */
 144     uint32_t last_error_ino;      /* I-node involved in last error */
 145     uint32_t last_error_line;     /* Line number where error happened */
 146     uint64_t last_error_block;    /* Block involved of last error */
 147     uint8_t last_error_func[32];  /* Function where the error happened */
 148     uint8_t mount_opts[64];
 149     uint32_t padding[112]; /* Padding to the end of the block */
 150 } __attribute__((packed));
 151
 152 #define EXT4_SUPERBLOCK_MAGIC 0xEF53
 153 #define EXT4_SUPERBLOCK_SIZE 1024
 154 #define EXT4_SUPERBLOCK_OFFSET 1024
 155
 156 #define EXT4_SUPERBLOCK_OS_LINUX 0
 157 #define EXT4_SUPERBLOCK_OS_HURD 1
 158
 159 /*
 160  * Misc. filesystem flags
 161  */
 162 #define EXT4_SUPERBLOCK_FLAGS_SIGNED_HASH 0x0001
 163 #define EXT4_SUPERBLOCK_FLAGS_UNSIGNED_HASH 0x0002
 164 #define EXT4_SUPERBLOCK_FLAGS_TEST_FILESYS 0x0004
 165 /*
 166  * Filesystem states
 167  */
 168 #define EXT4_SUPERBLOCK_STATE_VALID_FS 0x0001  /* Unmounted cleanly */
 169 #define EXT4_SUPERBLOCK_STATE_ERROR_FS 0x0002  /* Errors detected */
 170 #define EXT4_SUPERBLOCK_STATE_ORPHAN_FS 0x0004 /* Orphans being recovered */
 171
 172 /*
 173  * Behaviour when errors detected
 174  */
 175 #define EXT4_SUPERBLOCK_ERRORS_CONTINUE 1 /* Continue execution */
 176 #define EXT4_SUPERBLOCK_ERRORS_RO 2       /* Remount fs read-only */
 177 #define EXT4_SUPERBLOCK_ERRORS_PANIC 3    /* Panic */
 178 #define EXT4_SUPERBLOCK_ERRORS_DEFAULT EXT4_ERRORS_CONTINUE
 179
 180 /*
 181  * Compatible features
 182  */
 183 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC 0x0001
 184 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES 0x0002
 185 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL 0x0004
 186 #define EXT4_FEATURE_COMPAT_EXT_ATTR 0x0008
 187 #define EXT4_FEATURE_COMPAT_RESIZE_INODE 0x0010
 188 #define EXT4_FEATURE_COMPAT_DIR_INDEX 0x0020
 189
 190 /*
 191  * Read-only compatible features
 192  */
 193 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
 194 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
 195 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR 0x0004
 196 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008
 197 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010
 198 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020
 199 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040
 200 #define EXT4_FEATURE_RO_COMPAT_QUOTA 0x0100
 201 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC 0x0200
 202 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM 0x0400
 203
 204 /*
 205  * Incompatible features
 206  */
 207 #define EXT4_FEATURE_INCOMPAT_COMPRESSION 0x0001
 208 #define EXT4_FEATURE_INCOMPAT_FILETYPE 0x0002
 209 #define EXT4_FEATURE_INCOMPAT_RECOVER 0x0004     /* Needs recovery */
 210 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */
 211 #define EXT4_FEATURE_INCOMPAT_META_BG 0x0010
 212 #define EXT4_FEATURE_INCOMPAT_EXTENTS 0x0040 /* extents support */
 213 #define EXT4_FEATURE_INCOMPAT_64BIT 0x0080
 214 #define EXT4_FEATURE_INCOMPAT_MMP 0x0100
 215 #define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200
 216 #define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400         /* EA in inode */
 217 #define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000          /* data in dirent */
 218 #define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM 0x2000 /* use crc32c for bg */
 219 #define EXT4_FEATURE_INCOMPAT_LARGEDIR 0x4000         /* >2GB or 3-lvl htree */
 220 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA 0x8000      /* data in inode */
 221
 222 /*
 223  * EXT2 supported feature set
 224  */
 225 #define EXT2_FEATURE_COMPAT_SUPP 0x0000
 226
 227 #define EXT2_FEATURE_INCOMPAT_SUPP                                             \
 228     (EXT4_FEATURE_INCOMPAT_FILETYPE | EXT4_FEATURE_INCOMPAT_META_BG)
 229
 230 #define EXT2_FEATURE_RO_COMPAT_SUPP                                            \
 231     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER | EXT4_FEATURE_RO_COMPAT_LARGE_FILE | \
 232      EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
 233
 234 /*
 235  * EXT3 supported feature set
 236  */
 237 #define EXT3_FEATURE_COMPAT_SUPP (EXT4_FEATURE_COMPAT_DIR_INDEX)
 238
 239 #define EXT3_FEATURE_INCOMPAT_SUPP                                             \
 240     (EXT4_FEATURE_INCOMPAT_FILETYPE | EXT4_FEATURE_INCOMPAT_META_BG)
 241
 242 #define EXT3_FEATURE_RO_COMPAT_SUPP                                            \
 243     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER | EXT4_FEATURE_RO_COMPAT_LARGE_FILE | \
 244      EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
 245
 246 /*
 247  * EXT4 supported feature set
 248  */
 249 #define EXT4_FEATURE_COMPAT_SUPP (EXT4_FEATURE_COMPAT_DIR_INDEX)
 250
 251 #define EXT4_FEATURE_INCOMPAT_SUPP                                             \
 252     (EXT4_FEATURE_INCOMPAT_FILETYPE | EXT4_FEATURE_INCOMPAT_META_BG |          \
 253      EXT4_FEATURE_INCOMPAT_EXTENTS | EXT4_FEATURE_INCOMPAT_FLEX_BG |           \
 254      EXT4_FEATURE_INCOMPAT_64BIT)
 255
 256 #define EXT4_FEATURE_RO_COMPAT_SUPP                                            \
 257     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER | EXT4_FEATURE_RO_COMPAT_LARGE_FILE | \
 258      EXT4_FEATURE_RO_COMPAT_GDT_CSUM | EXT4_FEATURE_RO_COMPAT_DIR_NLINK |      \
 259      EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | EXT4_FEATURE_RO_COMPAT_BTREE_DIR |   \
 260      EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
 261
 262 /*Ignored features:
 263  * RECOVER - journaling in lwext4 is not supported
 264  *           (probably won,t be ever...)
 265  * MMP - multi mout protection (impossible scenario)
 266  * */
 267 #define FEATURE_INCOMPAT_IGNORED                                               \
 268     EXT4_FEATURE_INCOMPAT_RECOVER | EXT4_FEATURE_INCOMPAT_MMP
 269
 270 #if 0
 271 /*TODO: Features incompatible to implement*/
 272 #define EXT4_FEATURE_INCOMPAT_SUPP
 273                      (EXT4_FEATURE_INCOMPAT_INLINE_DATA)
 274
 275 /*TODO: Features read only to implement*/
 276 #define EXT4_FEATURE_RO_COMPAT_SUPP
 277                      EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
 278                      EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
 279                      EXT4_FEATURE_RO_COMPAT_QUOTA)
 280 #endif
 281
 282 struct ext4_fs {
 283     struct ext4_blockdev *bdev;
 284     struct ext4_sblock sb;
 285
 286     uint64_t inode_block_limits[4];
 287     uint64_t inode_blocks_per_level[4];
 288
 289     uint32_t last_inode_bg_id;
 290 };
 291
 292 /* Inode table/bitmap not in use */
 293 #define EXT4_BLOCK_GROUP_INODE_UNINIT 0x0001
 294 /* Block bitmap not in use */
 295 #define EXT4_BLOCK_GROUP_BLOCK_UNINIT 0x0002
 296 /* On-disk itable initialized to zero */
 297 #define EXT4_BLOCK_GROUP_ITABLE_ZEROED 0x0004
 298
 299 /*
 300  * Structure of a blocks group descriptor
 301  */
 302 struct ext4_bgroup {
 303     uint32_t block_bitmap_lo;            /* Blocks bitmap block */
 304     uint32_t inode_bitmap_lo;            /* Inodes bitmap block */
 305     uint32_t inode_table_first_block_lo; /* Inodes table block */
 306     uint16_t free_blocks_count_lo;       /* Free blocks count */
 307     uint16_t free_inodes_count_lo;       /* Free inodes count */
 308     uint16_t used_dirs_count_lo;         /* Directories count */
 309     uint16_t flags;                      /* EXT4_BG_flags (INODE_UNINIT, etc) */
 310     uint32_t exclude_bitmap_lo;          /* Exclude bitmap for snapshots */
 311     uint16_t block_bitmap_csum_lo;       /* crc32c(s_uuid+grp_num+bbitmap) LE */
 312     uint16_t inode_bitmap_csum_lo;       /* crc32c(s_uuid+grp_num+ibitmap) LE */
 313     uint16_t itable_unused_lo;           /* Unused inodes count */
 314     uint16_t checksum;                   /* crc16(sb_uuid+group+desc) */
 315
 316     uint32_t block_bitmap_hi;            /* Blocks bitmap block MSB */
 317     uint32_t inode_bitmap_hi;            /* I-nodes bitmap block MSB */
 318     uint32_t inode_table_first_block_hi; /* I-nodes table block MSB */
 319     uint16_t free_blocks_count_hi;       /* Free blocks count MSB */
 320     uint16_t free_inodes_count_hi;       /* Free i-nodes count MSB */
 321     uint16_t used_dirs_count_hi;         /* Directories count MSB */
 322     uint16_t itable_unused_hi;           /* Unused inodes count MSB */
 323     uint32_t exclude_bitmap_hi;          /* Exclude bitmap block MSB */
 324     uint16_t block_bitmap_csum_hi;       /* crc32c(s_uuid+grp_num+bbitmap) BE */
 325     uint16_t inode_bitmap_csum_hi;       /* crc32c(s_uuid+grp_num+ibitmap) BE */
 326     uint32_t reserved;                   /* Padding */
 327 };
 328
 329 struct ext4_block_group_ref {
 330     struct ext4_block block;
 331     struct ext4_bgroup *block_group;
 332     struct ext4_fs *fs;
 333     uint32_t index;
 334     bool dirty;
 335 };
 336
 337 #define EXT4_MIN_BLOCK_GROUP_DESCRIPTOR_SIZE 32
 338 #define EXT4_MAX_BLOCK_GROUP_DESCRIPTOR_SIZE 64
 339
 340 #define EXT4_MIN_BLOCK_SIZE 1024  /* 1 KiB */
 341 #define EXT4_MAX_BLOCK_SIZE 65536 /* 64 KiB */
 342 #define EXT4_REV0_INODE_SIZE 128
 343
 344 #define EXT4_INODE_BLOCK_SIZE 512
 345
 346 #define EXT4_INODE_DIRECT_BLOCK_COUNT 12
 347 #define EXT4_INODE_INDIRECT_BLOCK EXT4_INODE_DIRECT_BLOCK_COUNT
 348 #define EXT4_INODE_DOUBLE_INDIRECT_BLOCK (EXT4_INODE_INDIRECT_BLOCK + 1)
 349 #define EXT4_INODE_TRIPPLE_INDIRECT_BLOCK (EXT4_INODE_DOUBLE_INDIRECT_BLOCK + 1)
 350 #define EXT4_INODE_BLOCKS (EXT4_INODE_TRIPPLE_INDIRECT_BLOCK + 1)
 351 #define EXT4_INODE_INDIRECT_BLOCK_COUNT                                        \
 352     (EXT4_INODE_BLOCKS - EXT4_INODE_DIRECT_BLOCK_COUNT)
 353
 354 /*
 355  * Structure of an inode on the disk
 356  */
 357 struct ext4_inode {
 358     uint16_t mode;                      /* File mode */
 359     uint16_t uid;                       /* Low 16 bits of owner uid */
 360     uint32_t size_lo;                   /* Size in bytes */
 361     uint32_t access_time;               /* Access time */
 362     uint32_t change_inode_time;         /* I-node change time */
 363     uint32_t modification_time;         /* Modification time */
 364     uint32_t deletion_time;             /* Deletion time */
 365     uint16_t gid;                       /* Low 16 bits of group id */
 366     uint16_t links_count;               /* Links count */
 367     uint32_t blocks_count_lo;           /* Blocks count */
 368     uint32_t flags;                     /* File flags */
 369     uint32_t unused_osd1;               /* OS dependent - not used in HelenOS */
 370     uint32_t blocks[EXT4_INODE_BLOCKS]; /* Pointers to blocks */
 371     uint32_t generation;                /* File version (for NFS) */
 372     uint32_t file_acl_lo;               /* File ACL */
 373     uint32_t size_hi;
 374     uint32_t obso_faddr; /* Obsoleted fragment address */
 375
 376     union {
 377         struct {
 378             uint16_t blocks_high;
 379             uint16_t file_acl_high;
 380             uint16_t uid_high;
 381             uint16_t gid_high;
 382             uint32_t reserved2;
 383         } linux2;
 384         struct {
 385             uint16_t reserved1;
 386             uint16_t mode_high;
 387             uint16_t uid_high;
 388             uint16_t gid_high;
 389             uint32_t author;
 390         } hurd2;
 391     } __attribute__((packed)) osd2;
 392
 393     uint16_t extra_isize;
 394     uint16_t pad1;
 395     uint32_t ctime_extra;  /* Extra change time (nsec << 2 | epoch) */
 396     uint32_t mtime_extra;  /* Extra Modification time (nsec << 2 | epoch) */
 397     uint32_t atime_extra;  /* Extra Access time (nsec << 2 | epoch) */
 398     uint32_t crtime;       /* File creation time */
 399     uint32_t crtime_extra; /* Extra file creation time (nsec << 2 | epoch) */
 400     uint32_t version_hi;   /* High 32 bits for 64-bit version */
 401 } __attribute__((packed));
 402
 403 #define EXT4_INODE_MODE_FIFO 0x1000
 404 #define EXT4_INODE_MODE_CHARDEV 0x2000
 405 #define EXT4_INODE_MODE_DIRECTORY 0x4000
 406 #define EXT4_INODE_MODE_BLOCKDEV 0x6000
 407 #define EXT4_INODE_MODE_FILE 0x8000
 408 #define EXT4_INODE_MODE_SOFTLINK 0xA000
 409 #define EXT4_INODE_MODE_SOCKET 0xC000
 410 #define EXT4_INODE_MODE_TYPE_MASK 0xF000
 411
 412 /*
 413  * Inode flags
 414  */
 415 #define EXT4_INODE_FLAG_SECRM 0x00000001     /* Secure deletion */
 416 #define EXT4_INODE_FLAG_UNRM 0x00000002      /* Undelete */
 417 #define EXT4_INODE_FLAG_COMPR 0x00000004     /* Compress file */
 418 #define EXT4_INODE_FLAG_SYNC 0x00000008      /* Synchronous updates */
 419 #define EXT4_INODE_FLAG_IMMUTABLE 0x00000010 /* Immutable file */
 420 #define EXT4_INODE_FLAG_APPEND 0x00000020  /* writes to file may only append */
 421 #define EXT4_INODE_FLAG_NODUMP 0x00000040  /* do not dump file */
 422 #define EXT4_INODE_FLAG_NOATIME 0x00000080 /* do not update atime */
 423
 424 /* Compression flags */
 425 #define EXT4_INODE_FLAG_DIRTY 0x00000100
 426 #define EXT4_INODE_FLAG_COMPRBLK                                               \
 427     0x00000200                             /* One or more compressed clusters */
 428 #define EXT4_INODE_FLAG_NOCOMPR 0x00000400 /* Don't compress */
 429 #define EXT4_INODE_FLAG_ECOMPR 0x00000800  /* Compression error */
 430
 431 #define EXT4_INODE_FLAG_INDEX 0x00001000  /* hash-indexed directory */
 432 #define EXT4_INODE_FLAG_IMAGIC 0x00002000 /* AFS directory */
 433 #define EXT4_INODE_FLAG_JOURNAL_DATA                                           \
 434     0x00004000                            /* File data should be journaled */
 435 #define EXT4_INODE_FLAG_NOTAIL 0x00008000 /* File tail should not be merged */
 436 #define EXT4_INODE_FLAG_DIRSYNC                                                \
 437     0x00010000 /* Dirsync behaviour (directories only) */
 438 #define EXT4_INODE_FLAG_TOPDIR 0x00020000    /* Top of directory hierarchies */
 439 #define EXT4_INODE_FLAG_HUGE_FILE 0x00040000 /* Set to each huge file */
 440 #define EXT4_INODE_FLAG_EXTENTS 0x00080000   /* Inode uses extents */
 441 #define EXT4_INODE_FLAG_EA_INODE 0x00200000  /* Inode used for large EA */
 442 #define EXT4_INODE_FLAG_EOFBLOCKS 0x00400000 /* Blocks allocated beyond EOF */
 443 #define EXT4_INODE_FLAG_RESERVED 0x80000000  /* reserved for ext4 lib */
 444
 445 #define EXT4_INODE_ROOT_INDEX 2
 446
 447 struct ext4_inode_ref {
 448     struct ext4_block block;
 449     struct ext4_inode *inode;
 450     struct ext4_fs *fs;
 451     uint32_t index;
 452     bool dirty;
 453 };
 454
 455 #define EXT4_DIRECTORY_FILENAME_LEN 255
 456
 457 #define EXT4_DIRECTORY_FILETYPE_UNKNOWN 0
 458 #define EXT4_DIRECTORY_FILETYPE_REG_FILE 1
 459 #define EXT4_DIRECTORY_FILETYPE_DIR 2
 460 #define EXT4_DIRECTORY_FILETYPE_CHRDEV 3
 461 #define EXT4_DIRECTORY_FILETYPE_BLKDEV 4
 462 #define EXT4_DIRECTORY_FILETYPE_FIFO 5
 463 #define EXT4_DIRECTORY_FILETYPE_SOCK 6
 464 #define EXT4_DIRECTORY_FILETYPE_SYMLINK 7
 465
 466 union ext4_directory_entry_ll_internal {
 467     uint8_t name_length_high; /* Higher 8 bits of name length */
 468     uint8_t inode_type;       /* Type of referenced inode (in rev >= 0.5) */
 469 } __attribute__((packed));
 470
 471 /**
 472  * Linked list directory entry structure
 473  */
 474 struct ext4_directory_entry_ll {
 475     uint32_t inode;        /* I-node for the entry */
 476     uint16_t entry_length; /* Distance to the next directory entry */
 477     uint8_t name_length;   /* Lower 8 bits of name length */
 478
 479     union ext4_directory_entry_ll_internal in;
 480
 481     uint8_t name[EXT4_DIRECTORY_FILENAME_LEN]; /* Entry name */
 482 } __attribute__((packed));
 483
 484 struct ext4_directory_iterator {
 485     struct ext4_inode_ref *inode_ref;
 486     struct ext4_block current_block;
 487     uint64_t current_offset;
 488     struct ext4_directory_entry_ll *current;
 489 };
 490
 491 struct ext4_directory_search_result {
 492     struct ext4_block block;
 493     struct ext4_directory_entry_ll *dentry;
 494 };
 495
 496 /* Structures for indexed directory */
 497
 498 struct ext4_directory_dx_countlimit {
 499     uint16_t limit;
 500     uint16_t count;
 501 };
 502
 503 struct ext4_directory_dx_dot_entry {
 504     uint32_t inode;
 505     uint16_t entry_length;
 506     uint8_t name_length;
 507     uint8_t inode_type;
 508     uint8_t name[4];
 509 };
 510
 511 struct ext4_directory_dx_root_info {
 512     uint32_t reserved_zero;
 513     uint8_t hash_version;
 514     uint8_t info_length;
 515     uint8_t indirect_levels;
 516     uint8_t unused_flags;
 517 };
 518
 519 struct ext4_directory_dx_entry {
 520     uint32_t hash;
 521     uint32_t block;
 522 };
 523
 524 struct ext4_directory_dx_root {
 525     struct ext4_directory_dx_dot_entry dots[2];
 526     struct ext4_directory_dx_root_info info;
 527     struct ext4_directory_dx_entry entries[];
 528 };
 529
 530 struct ext4_fake_directory_entry {
 531     uint32_t inode;
 532     uint16_t entry_length;
 533     uint8_t name_length;
 534     uint8_t inode_type;
 535 };
 536
 537 struct ext4_directory_dx_node {
 538     struct ext4_fake_directory_entry fake;
 539     struct ext4_directory_dx_entry entries[];
 540 };
 541
 542 struct ext4_directory_dx_block {
 543     struct ext4_block block;
 544     struct ext4_directory_dx_entry *entries;
 545     struct ext4_directory_dx_entry *position;
 546 };
 547
 548 #define EXT4_ERR_BAD_DX_DIR (-25000)
 549
 550 #define EXT4_LINK_MAX 65000
 551
 552 /*
 553  * This is the extent on-disk structure.
 554  * It's used at the bottom of the tree.
 555  */
 556 struct ext4_extent {
 557     uint32_t first_block; /* First logical block extent covers */
 558     uint16_t block_count; /* Number of blocks covered by extent */
 559     uint16_t start_hi;    /* High 16 bits of physical block */
 560     uint32_t start_lo;    /* Low 32 bits of physical block */
 561 };
 562
 563 /*
 564  * This is index on-disk structure.
 565  * It's used at all the levels except the bottom.
 566  */
 567 struct ext4_extent_index {
 568     uint32_t first_block; /* Index covers logical blocks from 'block' */
 569
 570     /**
 571      * Pointer to the physical block of the next
 572      * level. leaf or next index could be there
 573      * high 16 bits of physical block
 574      */
 575     uint32_t leaf_lo;
 576     uint16_t leaf_hi;
 577     uint16_t padding;
 578 };
 579
 580 /*
 581  * Each block (leaves and indexes), even inode-stored has header.
 582  */
 583 struct ext4_extent_header {
 584     uint16_t magic;
 585     uint16_t entries_count;     /* Number of valid entries */
 586     uint16_t max_entries_count; /* Capacity of store in entries */
 587     uint16_t depth;             /* Has tree real underlying blocks? */
 588     uint32_t generation;        /* generation of the tree */
 589 };
 590
 591 struct ext4_extent_path {
 592     struct ext4_block block;
 593     uint16_t depth;
 594     struct ext4_extent_header *header;
 595     struct ext4_extent_index *index;
 596     struct ext4_extent *extent;
 597 };
 598
 599 #define EXT4_EXTENT_MAGIC 0xF30A
 600
 601 #define EXT4_EXTENT_FIRST(header)                                              \
 602     ((struct ext4_extent *)(((char *)(header)) +                               \
 603                             sizeof(struct ext4_extent_header)))
 604
 605 #define EXT4_EXTENT_FIRST_INDEX(header)                                        \
 606     ((struct ext4_extent_index *)(((char *)(header)) +                         \
 607                                   sizeof(struct ext4_extent_header)))
 608
 609 /* EXT3 HTree directory indexing */
 610 #define EXT2_HTREE_LEGACY 0
 611 #define EXT2_HTREE_HALF_MD4 1
 612 #define EXT2_HTREE_TEA 2
 613 #define EXT2_HTREE_LEGACY_UNSIGNED 3
 614 #define EXT2_HTREE_HALF_MD4_UNSIGNED 4
 615 #define EXT2_HTREE_TEA_UNSIGNED 5
 616
 617 #define EXT2_HTREE_EOF 0x7FFFFFFFUL
 618
 619 struct ext4_hash_info {
 620     uint32_t hash;
 621     uint32_t minor_hash;
 622     uint32_t hash_version;
 623     const uint32_t *seed;
 624 };
 625
 626 /*****************************************************************************/
 627
 628 #ifdef CONFIG_BIG_ENDIAN
 629 static inline uint64_t to_le64(uint64_t n)
 630 {
 631     return ((n & 0xff) << 56) | ((n & 0xff00) << 40) | ((n & 0xff0000) << 24) |
 632            ((n & 0xff000000LL) << 8) | ((n & 0xff00000000LL) >> 8) |
 633            ((n & 0xff0000000000LL) >> 24) | ((n & 0xff000000000000LL) >> 40) |
 634            ((n & 0xff00000000000000LL) >> 56);
 635 }
 636
 637 static inline uint32_t to_le32(uint32_t n)
 638 {
 639     return ((n & 0xff) << 24) | ((n & 0xff00) << 8) | ((n & 0xff0000) >> 8) |
 640            ((n & 0xff000000) >> 24);
 641 }
 642
 643 static inline uint16_t to_le16(uint16_t n)
 644 {
 645     return ((n & 0xff) << 8) | ((n & 0xff00) >> 8);
 646 }
 647
 648 #else
 649 #define to_le64(_n) _n
 650 #define to_le32(_n) _n
 651 #define to_le16(_n) _n
 652 #endif
 653
 654 /****************************Access macros to ext4 structures*****************/
 655
 656 #define ext4_get32(s, f) to_le32((s)->f)
 657 #define ext4_get16(s, f) to_le16((s)->f)
 658 #define ext4_get8(s, f) (s)->f
 659
 660 #define ext4_set32(s, f, v)                                                    \
 661     do {                                                                       \
 662         (s)->f = to_le32(v);                                                   \
 663     } while (0)
 664 #define ext4_set16(s, f, v)                                                    \
 665     do {                                                                       \
 666         (s)->f = to_le16(v);                                                   \
 667     } while (0)
 668 #define ext4_set8                                                              \
 669     (s, f, v) do { (s)->f = (v); }                                             \
 670     while (0)
 671
 672 #endif /* EXT4_TYPES_H_ */
 673
 674 /**
 675  * @}
 676  */