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 #include "tree.h"
  48
  49 #include <stdint.h>
  50
  51 #define EXT4_CHECKSUM_CRC32C 1
  52
  53 /*
  54  * Structure of the super block
  55  */
  56 struct ext4_sblock {
  57         uint32_t inodes_count;             /* I-nodes count */
  58         uint32_t blocks_count_lo;         /* Blocks count */
  59         uint32_t reserved_blocks_count_lo; /* Reserved blocks count */
  60         uint32_t free_blocks_count_lo;     /* Free blocks count */
  61         uint32_t free_inodes_count;     /* Free inodes count */
  62         uint32_t first_data_block;       /* First Data Block */
  63         uint32_t log_block_size;           /* Block size */
  64         uint32_t log_cluster_size;       /* Obsoleted fragment size */
  65         uint32_t blocks_per_group;       /* Number of blocks per group */
  66         uint32_t frags_per_group;         /* Obsoleted fragments per group */
  67         uint32_t inodes_per_group;       /* Number of inodes per group */
  68         uint32_t mount_time;               /* Mount time */
  69         uint32_t write_time;               /* Write time */
  70         uint16_t mount_count;              /* Mount count */
  71         uint16_t max_mount_count;         /* Maximal mount count */
  72         uint16_t magic;                    /* Magic signature */
  73         uint16_t state;                    /* File system state */
  74         uint16_t errors;                   /* Behavior when detecting errors */
  75         uint16_t minor_rev_level;         /* Minor revision level */
  76         uint32_t last_check_time;         /* Time of last check */
  77         uint32_t check_interval;           /* Maximum time between checks */
  78         uint32_t creator_os;               /* Creator OS */
  79         uint32_t rev_level;                /* Revision level */
  80         uint16_t def_resuid;               /* Default uid for reserved blocks */
  81         uint16_t def_resgid;               /* Default gid for reserved blocks */
  82
  83         /* Fields for EXT4_DYNAMIC_REV superblocks only. */
  84         uint32_t first_inode;    /* First non-reserved inode */
  85         uint16_t inode_size;      /* Size of inode structure */
  86         uint16_t block_group_index;   /* Block group index of this superblock */
  87         uint32_t features_compatible; /* Compatible feature set */
  88         uint32_t features_incompatible;  /* Incompatible feature set */
  89         uint32_t features_read_only;     /* Readonly-compatible feature set */
  90         uint8_t uuid[16];                /* 128-bit uuid for volume */
  91         char volume_name[16];            /* Volume name */
  92         char last_mounted[64];           /* Directory where last mounted */
  93         uint32_t algorithm_usage_bitmap; /* For compression */
  94
  95         /*
  96          * Performance hints. Directory preallocation should only
  97          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
  98          */
  99         uint8_t s_prealloc_blocks; /* Number of blocks to try to preallocate */
 100         uint8_t s_prealloc_dir_blocks;  /* Number to preallocate for dirs */
 101         uint16_t s_reserved_gdt_blocks; /* Per group desc for online growth */
 102
 103         /*
 104          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
 105          */
 106         uint8_t journal_uuid[16];      /* UUID of journal superblock */
 107         uint32_t journal_inode_number; /* Inode number of journal file */
 108         uint32_t journal_dev;     /* Device number of journal file */
 109         uint32_t last_orphan;     /* Head of list of inodes to delete */
 110         uint32_t hash_seed[4];   /* HTREE hash seed */
 111         uint8_t default_hash_version;  /* Default hash version to use */
 112         uint8_t journal_backup_type;
 113         uint16_t desc_size;       /* Size of group descriptor */
 114         uint32_t default_mount_opts; /* Default mount options */
 115         uint32_t first_meta_bg;      /* First metablock block group */
 116         uint32_t mkfs_time;       /* When the filesystem was created */
 117         uint32_t journal_blocks[17]; /* Backup of the journal inode */
 118
 119         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
 120         uint32_t blocks_count_hi;         /* Blocks count */
 121         uint32_t reserved_blocks_count_hi; /* Reserved blocks count */
 122         uint32_t free_blocks_count_hi;     /* Free blocks count */
 123         uint16_t min_extra_isize;    /* All inodes have at least # bytes */
 124         uint16_t want_extra_isize;   /* New inodes should reserve # bytes */
 125         uint32_t flags;              /* Miscellaneous flags */
 126         uint16_t raid_stride;   /* RAID stride */
 127         uint16_t mmp_interval;       /* # seconds to wait in MMP checking */
 128         uint64_t mmp_block;       /* Block for multi-mount protection */
 129         uint32_t raid_stripe_width;  /* Blocks on all data disks (N * stride) */
 130         uint8_t log_groups_per_flex; /* FLEX_BG group size */
 131         uint8_t checksum_type;
 132         uint16_t reserved_pad;
 133         uint64_t kbytes_written; /* Number of lifetime kilobytes written */
 134         uint32_t snapshot_inum;  /* I-node number of active snapshot */
 135         uint32_t snapshot_id;    /* Sequential ID of active snapshot */
 136         uint64_t
 137             snapshot_r_blocks_count; /* Reserved blocks for active snapshot's
 138                                         future use */
 139         uint32_t
 140             snapshot_list; /* I-node number of the head of the on-disk snapshot
 141                               list */
 142         uint32_t error_count;    /* Number of file system errors */
 143         uint32_t first_error_time;    /* First time an error happened */
 144         uint32_t first_error_ino;     /* I-node involved in first error */
 145         uint64_t first_error_block;   /* Block involved of first error */
 146         uint8_t first_error_func[32]; /* Function where the error happened */
 147         uint32_t first_error_line;    /* Line number where error happened */
 148         uint32_t last_error_time;     /* Most recent time of an error */
 149         uint32_t last_error_ino;      /* I-node involved in last error */
 150         uint32_t last_error_line;     /* Line number where error happened */
 151         uint64_t last_error_block;    /* Block involved of last error */
 152         uint8_t last_error_func[32];  /* Function where the error happened */
 153         uint8_t mount_opts[64];
 154         uint32_t usr_quota_inum;        /* inode for tracking user quota */
 155         uint32_t grp_quota_inum;        /* inode for tracking group quota */
 156         uint32_t overhead_clusters;     /* overhead blocks/clusters in fs */
 157         uint32_t backup_bgs[2]; /* groups with sparse_super2 SBs */
 158         uint8_t  encrypt_algos[4];      /* Encryption algorithms in use  */
 159         uint8_t  encrypt_pw_salt[16];   /* Salt used for string2key algorithm */
 160         uint32_t lpf_ino;               /* Location of the lost+found inode */
 161         uint32_t padding[100];  /* Padding to the end of the block */
 162         uint32_t checksum;              /* crc32c(superblock) */
 163 } __attribute__((packed));
 164
 165 #define EXT4_SUPERBLOCK_MAGIC 0xEF53
 166 #define EXT4_SUPERBLOCK_SIZE 1024
 167 #define EXT4_SUPERBLOCK_OFFSET 1024
 168
 169 #define EXT4_SUPERBLOCK_OS_LINUX 0
 170 #define EXT4_SUPERBLOCK_OS_HURD 1
 171
 172 /*
 173  * Misc. filesystem flags
 174  */
 175 #define EXT4_SUPERBLOCK_FLAGS_SIGNED_HASH 0x0001
 176 #define EXT4_SUPERBLOCK_FLAGS_UNSIGNED_HASH 0x0002
 177 #define EXT4_SUPERBLOCK_FLAGS_TEST_FILESYS 0x0004
 178 /*
 179  * Filesystem states
 180  */
 181 #define EXT4_SUPERBLOCK_STATE_VALID_FS 0x0001  /* Unmounted cleanly */
 182 #define EXT4_SUPERBLOCK_STATE_ERROR_FS 0x0002  /* Errors detected */
 183 #define EXT4_SUPERBLOCK_STATE_ORPHAN_FS 0x0004 /* Orphans being recovered */
 184
 185 /*
 186  * Behaviour when errors detected
 187  */
 188 #define EXT4_SUPERBLOCK_ERRORS_CONTINUE 1 /* Continue execution */
 189 #define EXT4_SUPERBLOCK_ERRORS_RO 2       /* Remount fs read-only */
 190 #define EXT4_SUPERBLOCK_ERRORS_PANIC 3    /* Panic */
 191 #define EXT4_SUPERBLOCK_ERRORS_DEFAULT EXT4_ERRORS_CONTINUE
 192
 193 /*
 194  * Compatible features
 195  */
 196 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC 0x0001
 197 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES 0x0002
 198 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL 0x0004
 199 #define EXT4_FEATURE_COMPAT_EXT_ATTR 0x0008
 200 #define EXT4_FEATURE_COMPAT_RESIZE_INODE 0x0010
 201 #define EXT4_FEATURE_COMPAT_DIR_INDEX 0x0020
 202
 203 /*
 204  * Read-only compatible features
 205  */
 206 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
 207 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
 208 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR 0x0004
 209 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008
 210 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010
 211 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020
 212 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE 0x0040
 213 #define EXT4_FEATURE_RO_COMPAT_QUOTA 0x0100
 214 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC 0x0200
 215 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM 0x0400
 216
 217 /*
 218  * Incompatible features
 219  */
 220 #define EXT4_FEATURE_INCOMPAT_COMPRESSION 0x0001
 221 #define EXT4_FEATURE_INCOMPAT_FILETYPE 0x0002
 222 #define EXT4_FEATURE_INCOMPAT_RECOVER 0x0004     /* Needs recovery */
 223 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008 /* Journal device */
 224 #define EXT4_FEATURE_INCOMPAT_META_BG 0x0010
 225 #define EXT4_FEATURE_INCOMPAT_EXTENTS 0x0040 /* extents support */
 226 #define EXT4_FEATURE_INCOMPAT_64BIT 0x0080
 227 #define EXT4_FEATURE_INCOMPAT_MMP 0x0100
 228 #define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200
 229 #define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400    /* EA in inode */
 230 #define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000      /* data in dirent */
 231 #define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM 0x2000 /* use crc32c for bg */
 232 #define EXT4_FEATURE_INCOMPAT_LARGEDIR 0x4000    /* >2GB or 3-lvl htree */
 233 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA 0x8000      /* data in inode */
 234
 235 /*
 236  * EXT2 supported feature set
 237  */
 238 #define EXT2_FEATURE_COMPAT_SUPP 0x0000
 239
 240 #define EXT2_FEATURE_INCOMPAT_SUPP                                             \
 241         (EXT4_FEATURE_INCOMPAT_FILETYPE | EXT4_FEATURE_INCOMPAT_META_BG)
 242
 243 #define EXT2_FEATURE_RO_COMPAT_SUPP                                            \
 244         (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER |                                 \
 245          EXT4_FEATURE_RO_COMPAT_LARGE_FILE | EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
 246
 247 /*
 248  * EXT3 supported feature set
 249  */
 250 #define EXT3_FEATURE_COMPAT_SUPP (EXT4_FEATURE_COMPAT_DIR_INDEX)
 251
 252 #define EXT3_FEATURE_INCOMPAT_SUPP                                             \
 253         (EXT4_FEATURE_INCOMPAT_FILETYPE | EXT4_FEATURE_INCOMPAT_META_BG)
 254
 255 #define EXT3_FEATURE_RO_COMPAT_SUPP                                            \
 256         (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER |                                 \
 257          EXT4_FEATURE_RO_COMPAT_LARGE_FILE | EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
 258
 259 /*
 260  * EXT4 supported feature set
 261  */
 262 #define EXT4_FEATURE_COMPAT_SUPP (EXT4_FEATURE_COMPAT_DIR_INDEX)
 263
 264 #define EXT4_FEATURE_INCOMPAT_SUPP                                             \
 265         (EXT4_FEATURE_INCOMPAT_FILETYPE | EXT4_FEATURE_INCOMPAT_META_BG |      \
 266          EXT4_FEATURE_INCOMPAT_EXTENTS | EXT4_FEATURE_INCOMPAT_FLEX_BG |       \
 267          EXT4_FEATURE_INCOMPAT_64BIT)
 268
 269 #define EXT4_FEATURE_RO_COMPAT_SUPP                                            \
 270         (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER |                                 \
 271          EXT4_FEATURE_RO_COMPAT_LARGE_FILE | EXT4_FEATURE_RO_COMPAT_GDT_CSUM | \
 272          EXT4_FEATURE_RO_COMPAT_DIR_NLINK |                                    \
 273          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE |                                  \
 274          EXT4_FEATURE_RO_COMPAT_BTREE_DIR | EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
 275
 276 /*Ignored features:
 277  * RECOVER - journaling in lwext4 is not supported
 278  *           (probably won't be ever...)
 279  * MMP - multi-mout protection (impossible scenario)
 280  * */
 281 #define FEATURE_INCOMPAT_IGNORED                                               \
 282         EXT4_FEATURE_INCOMPAT_RECOVER | EXT4_FEATURE_INCOMPAT_MMP
 283
 284 #if 0
 285 /*TODO: Features incompatible to implement*/
 286 #define EXT4_FEATURE_INCOMPAT_SUPP
 287                      (EXT4_FEATURE_INCOMPAT_INLINE_DATA)
 288
 289 /*TODO: Features read only to implement*/
 290 #define EXT4_FEATURE_RO_COMPAT_SUPP
 291                      EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
 292                      EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
 293                      EXT4_FEATURE_RO_COMPAT_QUOTA)
 294 #endif
 295
 296 struct ext4_fs {
 297         struct ext4_blockdev *bdev;
 298         struct ext4_sblock sb;
 299
 300         uint64_t inode_block_limits[4];
 301         uint64_t inode_blocks_per_level[4];
 302
 303         uint32_t last_inode_bg_id;
 304 };
 305
 306 /* Inode table/bitmap not in use */
 307 #define EXT4_BLOCK_GROUP_INODE_UNINIT 0x0001
 308 /* Block bitmap not in use */
 309 #define EXT4_BLOCK_GROUP_BLOCK_UNINIT 0x0002
 310 /* On-disk itable initialized to zero */
 311 #define EXT4_BLOCK_GROUP_ITABLE_ZEROED 0x0004
 312
 313 /*
 314  * Structure of a blocks group descriptor
 315  */
 316 struct ext4_bgroup {
 317         uint32_t block_bitmap_lo;           /* Blocks bitmap block */
 318         uint32_t inode_bitmap_lo;           /* Inodes bitmap block */
 319         uint32_t inode_table_first_block_lo; /* Inodes table block */
 320         uint16_t free_blocks_count_lo;       /* Free blocks count */
 321         uint16_t free_inodes_count_lo;       /* Free inodes count */
 322         uint16_t used_dirs_count_lo;     /* Directories count */
 323         uint16_t flags;                /* EXT4_BG_flags (INODE_UNINIT, etc) */
 324         uint32_t exclude_bitmap_lo;    /* Exclude bitmap for snapshots */
 325         uint16_t block_bitmap_csum_lo; /* crc32c(s_uuid+grp_num+bbitmap) LE */
 326         uint16_t inode_bitmap_csum_lo; /* crc32c(s_uuid+grp_num+ibitmap) LE */
 327         uint16_t itable_unused_lo;     /* Unused inodes count */
 328         uint16_t checksum;           /* crc16(sb_uuid+group+desc) */
 329
 330         uint32_t block_bitmap_hi;           /* Blocks bitmap block MSB */
 331         uint32_t inode_bitmap_hi;           /* I-nodes bitmap block MSB */
 332         uint32_t inode_table_first_block_hi; /* I-nodes table block MSB */
 333         uint16_t free_blocks_count_hi;       /* Free blocks count MSB */
 334         uint16_t free_inodes_count_hi;       /* Free i-nodes count MSB */
 335         uint16_t used_dirs_count_hi;     /* Directories count MSB */
 336         uint16_t itable_unused_hi;         /* Unused inodes count MSB */
 337         uint32_t exclude_bitmap_hi;       /* Exclude bitmap block MSB */
 338         uint16_t block_bitmap_csum_hi; /* crc32c(s_uuid+grp_num+bbitmap) BE */
 339         uint16_t inode_bitmap_csum_hi; /* crc32c(s_uuid+grp_num+ibitmap) BE */
 340         uint32_t reserved;           /* Padding */
 341 };
 342
 343 struct ext4_block_group_ref {
 344         struct ext4_block block;
 345         struct ext4_bgroup *block_group;
 346         struct ext4_fs *fs;
 347         uint32_t index;
 348         bool dirty;
 349 };
 350
 351 #define EXT4_MIN_BLOCK_GROUP_DESCRIPTOR_SIZE 32
 352 #define EXT4_MAX_BLOCK_GROUP_DESCRIPTOR_SIZE 64
 353
 354 #define EXT4_MIN_BLOCK_SIZE 1024  /* 1 KiB */
 355 #define EXT4_MAX_BLOCK_SIZE 65536 /* 64 KiB */
 356 #define EXT4_REV0_INODE_SIZE 128
 357
 358 #define EXT4_INODE_BLOCK_SIZE 512
 359
 360 #define EXT4_INODE_DIRECT_BLOCK_COUNT 12
 361 #define EXT4_INODE_INDIRECT_BLOCK EXT4_INODE_DIRECT_BLOCK_COUNT
 362 #define EXT4_INODE_DOUBLE_INDIRECT_BLOCK (EXT4_INODE_INDIRECT_BLOCK + 1)
 363 #define EXT4_INODE_TRIPPLE_INDIRECT_BLOCK (EXT4_INODE_DOUBLE_INDIRECT_BLOCK + 1)
 364 #define EXT4_INODE_BLOCKS (EXT4_INODE_TRIPPLE_INDIRECT_BLOCK + 1)
 365 #define EXT4_INODE_INDIRECT_BLOCK_COUNT                                        \
 366         (EXT4_INODE_BLOCKS - EXT4_INODE_DIRECT_BLOCK_COUNT)
 367
 368 /*
 369  * Structure of an inode on the disk
 370  */
 371 struct ext4_inode {
 372         uint16_t mode;              /* File mode */
 373         uint16_t uid;               /* Low 16 bits of owner uid */
 374         uint32_t size_lo;          /* Size in bytes */
 375         uint32_t access_time;       /* Access time */
 376         uint32_t change_inode_time; /* I-node change time */
 377         uint32_t modification_time; /* Modification time */
 378         uint32_t deletion_time;     /* Deletion time */
 379         uint16_t gid;               /* Low 16 bits of group id */
 380         uint16_t links_count;       /* Links count */
 381         uint32_t blocks_count_lo;   /* Blocks count */
 382         uint32_t flags;             /* File flags */
 383         uint32_t unused_osd1;       /* OS dependent - not used in HelenOS */
 384         uint32_t blocks[EXT4_INODE_BLOCKS]; /* Pointers to blocks */
 385         uint32_t generation;                /* File version (for NFS) */
 386         uint32_t file_acl_lo;               /* File ACL */
 387         uint32_t size_hi;
 388         uint32_t obso_faddr; /* Obsoleted fragment address */
 389
 390         union {
 391                 struct {
 392                         uint16_t blocks_high;
 393                         uint16_t file_acl_high;
 394                         uint16_t uid_high;
 395                         uint16_t gid_high;
 396                         uint16_t checksum_lo; /* crc32c(uuid+inum+inode) LE */
 397                         uint16_t reserved2;
 398                 } linux2;
 399                 struct {
 400                         uint16_t reserved1;
 401                         uint16_t mode_high;
 402                         uint16_t uid_high;
 403                         uint16_t gid_high;
 404                         uint32_t author;
 405                 } hurd2;
 406         } __attribute__((packed)) osd2;
 407
 408         uint16_t extra_isize;
 409         uint16_t checksum_hi;   /* crc32c(uuid+inum+inode) BE */
 410         uint32_t ctime_extra; /* Extra change time (nsec << 2 | epoch) */
 411         uint32_t mtime_extra; /* Extra Modification time (nsec << 2 | epoch) */
 412         uint32_t atime_extra; /* Extra Access time (nsec << 2 | epoch) */
 413         uint32_t crtime;      /* File creation time */
 414         uint32_t
 415             crtime_extra;    /* Extra file creation time (nsec << 2 | epoch) */
 416         uint32_t version_hi; /* High 32 bits for 64-bit version */
 417 } __attribute__((packed));
 418
 419 #define EXT4_INODE_MODE_FIFO 0x1000
 420 #define EXT4_INODE_MODE_CHARDEV 0x2000
 421 #define EXT4_INODE_MODE_DIRECTORY 0x4000
 422 #define EXT4_INODE_MODE_BLOCKDEV 0x6000
 423 #define EXT4_INODE_MODE_FILE 0x8000
 424 #define EXT4_INODE_MODE_SOFTLINK 0xA000
 425 #define EXT4_INODE_MODE_SOCKET 0xC000
 426 #define EXT4_INODE_MODE_TYPE_MASK 0xF000
 427
 428 /*
 429  * Inode flags
 430  */
 431 #define EXT4_INODE_FLAG_SECRM 0x00000001     /* Secure deletion */
 432 #define EXT4_INODE_FLAG_UNRM 0x00000002      /* Undelete */
 433 #define EXT4_INODE_FLAG_COMPR 0x00000004     /* Compress file */
 434 #define EXT4_INODE_FLAG_SYNC 0x00000008      /* Synchronous updates */
 435 #define EXT4_INODE_FLAG_IMMUTABLE 0x00000010 /* Immutable file */
 436 #define EXT4_INODE_FLAG_APPEND 0x00000020  /* writes to file may only append */
 437 #define EXT4_INODE_FLAG_NODUMP 0x00000040  /* do not dump file */
 438 #define EXT4_INODE_FLAG_NOATIME 0x00000080 /* do not update atime */
 439
 440 /* Compression flags */
 441 #define EXT4_INODE_FLAG_DIRTY 0x00000100
 442 #define EXT4_INODE_FLAG_COMPRBLK                                               \
 443         0x00000200                         /* One or more compressed clusters */
 444 #define EXT4_INODE_FLAG_NOCOMPR 0x00000400 /* Don't compress */
 445 #define EXT4_INODE_FLAG_ECOMPR 0x00000800  /* Compression error */
 446
 447 #define EXT4_INODE_FLAG_INDEX 0x00001000  /* hash-indexed directory */
 448 #define EXT4_INODE_FLAG_IMAGIC 0x00002000 /* AFS directory */
 449 #define EXT4_INODE_FLAG_JOURNAL_DATA                                           \
 450         0x00004000                        /* File data should be journaled */
 451 #define EXT4_INODE_FLAG_NOTAIL 0x00008000 /* File tail should not be merged */
 452 #define EXT4_INODE_FLAG_DIRSYNC                                                \
 453         0x00010000 /* Dirsync behaviour (directories only) */
 454 #define EXT4_INODE_FLAG_TOPDIR 0x00020000    /* Top of directory hierarchies */
 455 #define EXT4_INODE_FLAG_HUGE_FILE 0x00040000 /* Set to each huge file */
 456 #define EXT4_INODE_FLAG_EXTENTS 0x00080000   /* Inode uses extents */
 457 #define EXT4_INODE_FLAG_EA_INODE 0x00200000  /* Inode used for large EA */
 458 #define EXT4_INODE_FLAG_EOFBLOCKS 0x00400000 /* Blocks allocated beyond EOF */
 459 #define EXT4_INODE_FLAG_RESERVED 0x80000000  /* reserved for ext4 lib */
 460
 461 #define EXT4_INODE_ROOT_INDEX 2
 462
 463 struct ext4_inode_ref {
 464         struct ext4_block block;
 465         struct ext4_inode *inode;
 466         struct ext4_fs *fs;
 467         uint32_t index;
 468         bool dirty;
 469 };
 470
 471 #define EXT4_DIRECTORY_FILENAME_LEN 255
 472
 473 /**@brief   Directory entry types. */
 474 enum { EXT4_DIRENTRY_UNKNOWN = 0,
 475        EXT4_DIRENTRY_REG_FILE,
 476        EXT4_DIRENTRY_DIR,
 477        EXT4_DIRENTRY_CHRDEV,
 478        EXT4_DIRENTRY_BLKDEV,
 479        EXT4_DIRENTRY_FIFO,
 480        EXT4_DIRENTRY_SOCK,
 481        EXT4_DIRENTRY_SYMLINK };
 482
 483 #define EXT4_DIRENTRY_DIR_CSUM 0xDE
 484
 485 union ext4_directory_entry_ll_internal {
 486         uint8_t name_length_high; /* Higher 8 bits of name length */
 487         uint8_t inode_type;       /* Type of referenced inode (in rev >= 0.5) */
 488 } __attribute__((packed));
 489
 490 /**
 491  * Linked list directory entry structure
 492  */
 493 struct ext4_directory_entry_ll {
 494         uint32_t inode; /* I-node for the entry */
 495         uint16_t entry_length; /* Distance to the next directory entry */
 496         uint8_t name_length;   /* Lower 8 bits of name length */
 497
 498         union ext4_directory_entry_ll_internal in;
 499
 500         uint8_t name[EXT4_DIRECTORY_FILENAME_LEN]; /* Entry name */
 501 } __attribute__((packed));
 502
 503 struct ext4_directory_iterator {
 504         struct ext4_inode_ref *inode_ref;
 505         struct ext4_block current_block;
 506         uint64_t current_offset;
 507         struct ext4_directory_entry_ll *current;
 508 };
 509
 510 struct ext4_directory_search_result {
 511         struct ext4_block block;
 512         struct ext4_directory_entry_ll *dentry;
 513 };
 514
 515 /* Structures for indexed directory */
 516
 517 struct ext4_directory_dx_countlimit {
 518         uint16_t limit;
 519         uint16_t count;
 520 };
 521
 522 struct ext4_directory_dx_dot_entry {
 523         uint32_t inode;
 524         uint16_t entry_length;
 525         uint8_t name_length;
 526         uint8_t inode_type;
 527         uint8_t name[4];
 528 };
 529
 530 struct ext4_directory_dx_root_info {
 531         uint32_t reserved_zero;
 532         uint8_t hash_version;
 533         uint8_t info_length;
 534         uint8_t indirect_levels;
 535         uint8_t unused_flags;
 536 };
 537
 538 struct ext4_directory_dx_entry {
 539         uint32_t hash;
 540         uint32_t block;
 541 };
 542
 543 struct ext4_directory_dx_root {
 544         struct ext4_directory_dx_dot_entry dots[2];
 545         struct ext4_directory_dx_root_info info;
 546         struct ext4_directory_dx_entry entries[];
 547 };
 548
 549 struct ext4_fake_directory_entry {
 550         uint32_t inode;
 551         uint16_t entry_length;
 552         uint8_t name_length;
 553         uint8_t inode_type;
 554 };
 555
 556 struct ext4_directory_dx_node {
 557         struct ext4_fake_directory_entry fake;
 558         struct ext4_directory_dx_entry entries[];
 559 };
 560
 561 struct ext4_directory_dx_block {
 562         struct ext4_block block;
 563         struct ext4_directory_dx_entry *entries;
 564         struct ext4_directory_dx_entry *position;
 565 };
 566
 567 /*
 568  * This goes at the end of each htree block.
 569  */
 570 struct ext4_directory_dx_tail {
 571         uint32_t reserved;
 572         uint32_t checksum;      /* crc32c(uuid+inum+dirblock) */
 573 };
 574
 575 /*
 576  * This is a bogus directory entry at the end of each leaf block that
 577  * records checksums.
 578  */
 579 struct ext4_directory_entry_tail {
 580         uint32_t reserved_zero1;        /* Pretend to be unused */
 581         uint16_t rec_len;               /* 12 */
 582         uint8_t reserved_zero2; /* Zero name length */
 583         uint8_t reserved_ft;    /* 0xDE, fake file type */
 584         uint32_t checksum;              /* crc32c(uuid+inum+dirblock) */
 585 };
 586
 587 #define EXT4_DIRENT_TAIL(block, blocksize) \
 588         ((struct ext4_directory_entry_tail *)(((char *)(block)) + \
 589                                              ((blocksize) - \
 590                                              sizeof(struct ext4_directory_entry_tail))))
 591
 592 #define EXT4_ERR_BAD_DX_DIR (-25000)
 593
 594 #define EXT4_LINK_MAX 65000
 595
 596 #define EXT4_BAD_INO 1
 597 #define EXT4_ROOT_INO 2
 598 #define EXT4_BOOT_LOADER_INO 5
 599 #define EXT4_UNDEL_DIR_INO 6
 600 #define EXT4_RESIZE_INO 7
 601 #define EXT4_JOURNAL_INO 8
 602
 603 #define EXT4_GOOD_OLD_FIRST_INO 11
 604
 605 #define EXT4_EXT_UNWRITTEN_MASK (1L << 15)
 606
 607 #define EXT4_EXT_MAX_LEN_WRITTEN (1L << 15)
 608 #define EXT4_EXT_MAX_LEN_UNWRITTEN \
 609         (EXT4_EXT_MAX_LEN_WRITTEN - 1)
 610
 611 #define EXT4_EXT_GET_LEN(ex) to_le16((ex)->block_count)
 612 #define EXT4_EXT_GET_LEN_UNWRITTEN(ex) \
 613         (EXT4_EXT_GET_LEN(ex) &= ~(EXT4_EXT_UNWRITTEN_MASK))
 614 #define EXT4_EXT_SET_LEN(ex, count) \
 615         ((ex)->block_count = to_le16(count))
 616
 617 #define EXT4_EXT_IS_UNWRITTEN(ex) \
 618         (EXT4_EXT_GET_LEN(ex) > EXT4_EXT_MAX_LEN_WRITTEN)
 619 #define EXT4_EXT_SET_UNWRITTEN(ex) \
 620         ((ex)->block_count |= to_le16(EXT4_EXT_UNWRITTEN_MASK))
 621 #define EXT4_EXT_SET_WRITTEN(ex) \
 622         ((ex)->block_count &= ~(to_le16(EXT4_EXT_UNWRITTEN_MASK)))
 623 /*
 624  * This is the extent tail on-disk structure.
 625  * All other extent structures are 12 bytes long.  It turns out that
 626  * block_size % 12 >= 4 for at least all powers of 2 greater than 512, which
 627  * covers all valid ext4 block sizes.  Therefore, this tail structure can be
 628  * crammed into the end of the block without having to rebalance the tree.
 629  */
 630 struct ext4_extent_tail
 631 {
 632         uint32_t et_checksum; /* crc32c(uuid+inum+extent_block) */
 633 };
 634
 635 /*
 636  * This is the extent on-disk structure.
 637  * It's used at the bottom of the tree.
 638  */
 639 struct ext4_extent {
 640         uint32_t first_block; /* First logical block extent covers */
 641         uint16_t block_count; /* Number of blocks covered by extent */
 642         uint16_t start_hi;    /* High 16 bits of physical block */
 643         uint32_t start_lo;    /* Low 32 bits of physical block */
 644 };
 645
 646 /*
 647  * This is index on-disk structure.
 648  * It's used at all the levels except the bottom.
 649  */
 650 struct ext4_extent_index {
 651         uint32_t first_block; /* Index covers logical blocks from 'block' */
 652
 653         /**
 654          * Pointer to the physical block of the next
 655          * level. leaf or next index could be there
 656          * high 16 bits of physical block
 657          */
 658         uint32_t leaf_lo;
 659         uint16_t leaf_hi;
 660         uint16_t padding;
 661 };
 662
 663 /*
 664  * Each block (leaves and indexes), even inode-stored has header.
 665  */
 666 struct ext4_extent_header {
 667         uint16_t magic;
 668         uint16_t entries_count;     /* Number of valid entries */
 669         uint16_t max_entries_count; /* Capacity of store in entries */
 670         uint16_t depth;             /* Has tree real underlying blocks? */
 671         uint32_t generation;    /* generation of the tree */
 672 };
 673
 674
 675 /*
 676  * Types of blocks.
 677  */
 678 typedef uint32_t ext4_lblk_t;
 679 typedef uint64_t ext4_fsblk_t;
 680
 681 /*
 682  * Array of ext4_ext_path contains path to some extent.
 683  * Creation/lookup routines use it for traversal/splitting/etc.
 684  * Truncate uses it to simulate recursive walking.
 685  */
 686 struct ext4_extent_path {
 687         ext4_fsblk_t p_block;
 688         struct ext4_block block;
 689         int32_t depth;
 690         int32_t maxdepth;
 691         struct ext4_extent_header *header;
 692         struct ext4_extent_index *index;
 693         struct ext4_extent *extent;
 694
 695 };
 696
 697
 698 #define EXT4_EXTENT_MAGIC 0xF30A
 699
 700 #define EXT4_EXTENT_FIRST(header)                                              \
 701         ((struct ext4_extent *)(((char *)(header)) +                           \
 702                                 sizeof(struct ext4_extent_header)))
 703
 704 #define EXT4_EXTENT_FIRST_INDEX(header)                                        \
 705         ((struct ext4_extent_index *)(((char *)(header)) +                     \
 706                                       sizeof(struct ext4_extent_header)))
 707
 708 /*
 709  * EXT_INIT_MAX_LEN is the maximum number of blocks we can have in an
 710  * initialized extent. This is 2^15 and not (2^16 - 1), since we use the
 711  * MSB of ee_len field in the extent datastructure to signify if this
 712  * particular extent is an initialized extent or an uninitialized (i.e.
 713  * preallocated).
 714  * EXT_UNINIT_MAX_LEN is the maximum number of blocks we can have in an
 715  * uninitialized extent.
 716  * If ee_len is <= 0x8000, it is an initialized extent. Otherwise, it is an
 717  * uninitialized one. In other words, if MSB of ee_len is set, it is an
 718  * uninitialized extent with only one special scenario when ee_len = 0x8000.
 719  * In this case we can not have an uninitialized extent of zero length and
 720  * thus we make it as a special case of initialized extent with 0x8000 length.
 721  * This way we get better extent-to-group alignment for initialized extents.
 722  * Hence, the maximum number of blocks we can have in an *initialized*
 723  * extent is 2^15 (32768) and in an *uninitialized* extent is 2^15-1 (32767).
 724  */
 725 #define EXT_INIT_MAX_LEN (1L << 15)
 726 #define EXT_UNWRITTEN_MAX_LEN (EXT_INIT_MAX_LEN - 1)
 727
 728 #define EXT_EXTENT_SIZE sizeof(struct ext4_extent)
 729 #define EXT_INDEX_SIZE sizeof(struct ext4_extent_idx)
 730
 731 #define EXT_FIRST_EXTENT(__hdr__)                                              \
 732         ((struct ext4_extent *)(((char *)(__hdr__)) +                          \
 733                                 sizeof(struct ext4_extent_header)))
 734 #define EXT_FIRST_INDEX(__hdr__)                                               \
 735         ((struct ext4_extent_index *)(((char *)(__hdr__)) +                    \
 736                                     sizeof(struct ext4_extent_header)))
 737 #define EXT_HAS_FREE_INDEX(__path__)                                           \
 738         ((__path__)->header->entries_count < (__path__)->header->max_entries_count)
 739 #define EXT_LAST_EXTENT(__hdr__)                                               \
 740         (EXT_FIRST_EXTENT((__hdr__)) + (__hdr__)->entries_count - 1)
 741 #define EXT_LAST_INDEX(__hdr__)                                                \
 742         (EXT_FIRST_INDEX((__hdr__)) + (__hdr__)->entries_count - 1)
 743 #define EXT_MAX_EXTENT(__hdr__)                                                \
 744         (EXT_FIRST_EXTENT((__hdr__)) + (__hdr__)->max_entries_count - 1)
 745 #define EXT_MAX_INDEX(__hdr__)                                                 \
 746         (EXT_FIRST_INDEX((__hdr__)) + (__hdr__)->max_entries_count - 1)
 747
 748 #define EXT4_EXTENT_TAIL_OFFSET(hdr)                                           \
 749         (sizeof(struct ext4_extent_header) +                                   \
 750          (sizeof(struct ext4_extent) * (hdr)->max_entries_count))
 751
 752 /*
 753  * ext4_ext_next_allocated_block:
 754  * returns allocated block in subsequent extent or EXT_MAX_BLOCKS.
 755  * NOTE: it considers block number from index entry as
 756  * allocated block. Thus, index entries have to be consistent
 757  * with leaves.
 758  */
 759 #define EXT_MAX_BLOCKS (ext4_lblk_t) (-1)
 760
 761 #define IN_RANGE(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
 762
 763
 764 /******************************************************************************/
 765
 766 /* EXT3 HTree directory indexing */
 767 #define EXT2_HTREE_LEGACY 0
 768 #define EXT2_HTREE_HALF_MD4 1
 769 #define EXT2_HTREE_TEA 2
 770 #define EXT2_HTREE_LEGACY_UNSIGNED 3
 771 #define EXT2_HTREE_HALF_MD4_UNSIGNED 4
 772 #define EXT2_HTREE_TEA_UNSIGNED 5
 773
 774 #define EXT2_HTREE_EOF 0x7FFFFFFFUL
 775
 776 struct ext4_hash_info {
 777         uint32_t hash;
 778         uint32_t minor_hash;
 779         uint32_t hash_version;
 780         const uint32_t *seed;
 781 };
 782
 783 /* Extended Attribute(EA) */
 784
 785 /* Magic value in attribute blocks */
 786 #define EXT4_XATTR_MAGIC                0xEA020000
 787
 788 /* Maximum number of references to one attribute block */
 789 #define EXT4_XATTR_REFCOUNT_MAX         1024
 790
 791 /* Name indexes */
 792 #define EXT4_XATTR_INDEX_USER                   1
 793 #define EXT4_XATTR_INDEX_POSIX_ACL_ACCESS       2
 794 #define EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT      3
 795 #define EXT4_XATTR_INDEX_TRUSTED                4
 796 #define EXT4_XATTR_INDEX_LUSTRE                 5
 797 #define EXT4_XATTR_INDEX_SECURITY               6
 798 #define EXT4_XATTR_INDEX_SYSTEM                 7
 799 #define EXT4_XATTR_INDEX_RICHACL                8
 800 #define EXT4_XATTR_INDEX_ENCRYPTION             9
 801
 802 struct ext4_xattr_header {
 803         uint32_t h_magic;       /* magic number for identification */
 804         uint32_t h_refcount;    /* reference count */
 805         uint32_t h_blocks;      /* number of disk blocks used */
 806         uint32_t h_hash;                /* hash value of all attributes */
 807         uint32_t h_checksum;    /* crc32c(uuid+id+xattrblock) */
 808                                 /* id = inum if refcount=1, blknum otherwise */
 809         uint32_t h_reserved[3]; /* zero right now */
 810 } __attribute__((packed));
 811
 812 struct ext4_xattr_ibody_header {
 813         uint32_t h_magic;       /* magic number for identification */
 814 } __attribute__((packed));
 815
 816 struct ext4_xattr_entry {
 817         uint8_t e_name_len;     /* length of name */
 818         uint8_t e_name_index;   /* attribute name index */
 819         uint16_t e_value_offs;  /* offset in disk block of value */
 820         uint32_t e_value_block; /* disk block attribute is stored on (n/i) */
 821         uint32_t e_value_size;  /* size of attribute value */
 822         uint32_t e_hash;                /* hash value of name and value */
 823 } __attribute__((packed));
 824
 825 struct ext4_xattr_item {
 826         uint8_t name_index;
 827         char  *name;
 828         size_t name_len;
 829         void  *data;
 830         size_t data_size;
 831
 832         RB_ENTRY(ext4_xattr_item) node;
 833 };
 834
 835 struct ext4_xattr_ref {
 836         bool block_loaded;
 837         struct ext4_block block;
 838         struct ext4_inode_ref *inode_ref;
 839         bool   dirty;
 840         size_t ea_size;
 841         struct ext4_fs *fs;
 842
 843         void *iter_arg;
 844         struct ext4_xattr_item *iter_from;
 845
 846         RB_HEAD(ext4_xattr_tree,
 847                 ext4_xattr_item) root;
 848 };
 849
 850 #define EXT4_XATTR_ITERATE_CONT 0
 851 #define EXT4_XATTR_ITERATE_STOP 1
 852 #define EXT4_XATTR_ITERATE_PAUSE 2
 853
 854 #define EXT4_GOOD_OLD_INODE_SIZE        128
 855
 856 #define EXT4_XATTR_PAD_BITS             2
 857 #define EXT4_XATTR_PAD          (1<<EXT4_XATTR_PAD_BITS)
 858 #define EXT4_XATTR_ROUND                (EXT4_XATTR_PAD-1)
 859 #define EXT4_XATTR_LEN(name_len) \
 860         (((name_len) + EXT4_XATTR_ROUND + \
 861         sizeof(struct ext4_xattr_entry)) & ~EXT4_XATTR_ROUND)
 862 #define EXT4_XATTR_NEXT(entry) \
 863         ((struct ext4_xattr_entry *)( \
 864          (char *)(entry) + EXT4_XATTR_LEN((entry)->e_name_len)))
 865 #define EXT4_XATTR_SIZE(size) \
 866         (((size) + EXT4_XATTR_ROUND) & ~EXT4_XATTR_ROUND)
 867 #define EXT4_XATTR_NAME(entry) \
 868         ((char *)((entry) + 1))
 869
 870 #define EXT4_XATTR_IHDR(raw_inode) \
 871         ((struct ext4_xattr_ibody_header *) \
 872                 ((char *)raw_inode + \
 873                 EXT4_GOOD_OLD_INODE_SIZE + \
 874                 (raw_inode)->extra_isize))
 875 #define EXT4_XATTR_IFIRST(hdr) \
 876         ((struct ext4_xattr_entry *)((hdr)+1))
 877
 878 #define EXT4_XATTR_BHDR(block) \
 879         ((struct ext4_xattr_header *)((block)->data))
 880 #define EXT4_XATTR_ENTRY(ptr) \
 881         ((struct ext4_xattr_entry *)(ptr))
 882 #define EXT4_XATTR_BFIRST(block) \
 883         EXT4_XATTR_ENTRY(EXT4_XATTR_BHDR(block)+1)
 884 #define EXT4_XATTR_IS_LAST_ENTRY(entry) \
 885         (*(uint32_t *)(entry) == 0)
 886
 887 #define EXT4_ZERO_XATTR_VALUE ((void *)-1)
 888
 889 /*****************************************************************************/
 890
 891 #ifdef CONFIG_BIG_ENDIAN
 892 static inline uint64_t to_le64(uint64_t n)
 893 {
 894         return ((n & 0xff) << 56) | ((n & 0xff00) << 40) |
 895                 ((n & 0xff0000) << 24) | ((n & 0xff000000LL) << 8) |
 896                 ((n & 0xff00000000LL) >> 8) | ((n & 0xff0000000000LL) >> 24) |
 897                 ((n & 0xff000000000000LL) >> 40) |
 898                 ((n & 0xff00000000000000LL) >> 56);
 899 }
 900
 901 static inline uint32_t to_le32(uint32_t n)
 902 {
 903         return ((n & 0xff) << 24) | ((n & 0xff00) << 8) |
 904                 ((n & 0xff0000) >> 8) | ((n & 0xff000000) >> 24);
 905 }
 906
 907 static inline uint16_t to_le16(uint16_t n)
 908 {
 909         return ((n & 0xff) << 8) | ((n & 0xff00) >> 8);
 910 }
 911
 912 #else
 913 #define to_le64(_n) _n
 914 #define to_le32(_n) _n
 915 #define to_le16(_n) _n
 916 #endif
 917
 918 /****************************Access macros to ext4 structures*****************/
 919
 920 #define ext4_get32(s, f) to_le32((s)->f)
 921 #define ext4_get16(s, f) to_le16((s)->f)
 922 #define ext4_get8(s, f) (s)->f
 923
 924 #define ext4_set32(s, f, v)                                                    \
 925         do {                                                                   \
 926                 (s)->f = to_le32(v);                                           \
 927         } while (0)
 928 #define ext4_set16(s, f, v)                                                    \
 929         do {                                                                   \
 930                 (s)->f = to_le16(v);                                           \
 931         } while (0)
 932 #define ext4_set8                                                              \
 933         (s, f, v) do { (s)->f = (v); }                                         \
 934         while (0)
 935
 936 #endif /* EXT4_TYPES_H_ */
 937
 938 /**
 939  * @}
 940  */