include/linux/ext4_fs.h

   1 /*
   2  *  linux/include/linux/ext4_fs.h
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/include/linux/minix_fs.h
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  */
  15
  16 #ifndef _LINUX_EXT4_FS_H
  17 #define _LINUX_EXT4_FS_H
  18
  19 #include <linux/types.h>
  20 #include <linux/blkdev.h>
  21 #include <linux/magic.h>
  22
  23 /*
  24  * The second extended filesystem constants/structures
  25  */
  26
  27 /*
  28  * Define EXT4FS_DEBUG to produce debug messages
  29  */
  30 #undef EXT4FS_DEBUG
  31
  32 /*
  33  * Define EXT4_RESERVATION to reserve data blocks for expanding files
  34  */
  35 #define EXT4_DEFAULT_RESERVE_BLOCKS     8
  36 /*max window size: 1024(direct blocks) + 3([t,d]indirect blocks) */
  37 #define EXT4_MAX_RESERVE_BLOCKS         1027
  38 #define EXT4_RESERVE_WINDOW_NOT_ALLOCATED 0
  39 /*
  40  * Always enable hashed directories
  41  */
  42 #define CONFIG_EXT4_INDEX
  43
  44 /*
  45  * Debug code
  46  */
  47 #ifdef EXT4FS_DEBUG
  48 #define ext4_debug(f, a...)                                             \
  49         do {                                                            \
  50                 printk (KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",       \
  51                         __FILE__, __LINE__, __FUNCTION__);              \
  52                 printk (KERN_DEBUG f, ## a);                            \
  53         } while (0)
  54 #else
  55 #define ext4_debug(f, a...)     do {} while (0)
  56 #endif
  57
  58 /*
  59  * Special inodes numbers
  60  */
  61 #define EXT4_BAD_INO             1      /* Bad blocks inode */
  62 #define EXT4_ROOT_INO            2      /* Root inode */
  63 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
  64 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
  65 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
  66 #define EXT4_JOURNAL_INO         8      /* Journal inode */
  67
  68 /* First non-reserved inode for old ext4 filesystems */
  69 #define EXT4_GOOD_OLD_FIRST_INO 11
  70
  71 /*
  72  * Maximal count of links to a file
  73  */
  74 #define EXT4_LINK_MAX           32000
  75
  76 /*
  77  * Macro-instructions used to manage several block sizes
  78  */
  79 #define EXT4_MIN_BLOCK_SIZE             1024
  80 #define EXT4_MAX_BLOCK_SIZE             4096
  81 #define EXT4_MIN_BLOCK_LOG_SIZE           10
  82 #ifdef __KERNEL__
  83 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
  84 #else
  85 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
  86 #endif
  87 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof (__u32))
  88 #ifdef __KERNEL__
  89 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
  90 #else
  91 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
  92 #endif
  93 #ifdef __KERNEL__
  94 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
  95 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
  96 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
  97 #else
  98 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
  99                                  EXT4_GOOD_OLD_INODE_SIZE : \
 100                                  (s)->s_inode_size)
 101 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 102                                  EXT4_GOOD_OLD_FIRST_INO : \
 103                                  (s)->s_first_ino)
 104 #endif
 105
 106 /*
 107  * Macro-instructions used to manage fragments
 108  */
 109 #define EXT4_MIN_FRAG_SIZE              1024
 110 #define EXT4_MAX_FRAG_SIZE              4096
 111 #define EXT4_MIN_FRAG_LOG_SIZE            10
 112 #ifdef __KERNEL__
 113 # define EXT4_FRAG_SIZE(s)              (EXT4_SB(s)->s_frag_size)
 114 # define EXT4_FRAGS_PER_BLOCK(s)        (EXT4_SB(s)->s_frags_per_block)
 115 #else
 116 # define EXT4_FRAG_SIZE(s)              (EXT4_MIN_FRAG_SIZE << (s)->s_log_frag_size)
 117 # define EXT4_FRAGS_PER_BLOCK(s)        (EXT4_BLOCK_SIZE(s) / EXT4_FRAG_SIZE(s))
 118 #endif
 119
 120 /*
 121  * Structure of a blocks group descriptor
 122  */
 123 struct ext4_group_desc
 124 {
 125         __le32  bg_block_bitmap;                /* Blocks bitmap block */
 126         __le32  bg_inode_bitmap;                /* Inodes bitmap block */
 127         __le32  bg_inode_table;         /* Inodes table block */
 128         __le16  bg_free_blocks_count;   /* Free blocks count */
 129         __le16  bg_free_inodes_count;   /* Free inodes count */
 130         __le16  bg_used_dirs_count;     /* Directories count */
 131         __u16   bg_pad;
 132         __le32  bg_reserved[3];
 133 };
 134
 135 /*
 136  * Macro-instructions used to manage group descriptors
 137  */
 138 #ifdef __KERNEL__
 139 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
 140 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
 141 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
 142 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
 143 #else
 144 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 145 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / sizeof (struct ext4_group_desc))
 146 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 147 #endif
 148
 149 /*
 150  * Constants relative to the data blocks
 151  */
 152 #define EXT4_NDIR_BLOCKS                12
 153 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
 154 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
 155 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
 156 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
 157
 158 /*
 159  * Inode flags
 160  */
 161 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
 162 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
 163 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
 164 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
 165 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
 166 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
 167 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
 168 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
 169 /* Reserved for compression usage... */
 170 #define EXT4_DIRTY_FL                   0x00000100
 171 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 172 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
 173 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
 174 /* End compression flags --- maybe not all used */
 175 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
 176 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
 177 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
 178 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
 179 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
 180 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
 181 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
 182 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 183
 184 #define EXT4_FL_USER_VISIBLE            0x000BDFFF /* User visible flags */
 185 #define EXT4_FL_USER_MODIFIABLE         0x000380FF /* User modifiable flags */
 186
 187 /*
 188  * Inode dynamic state flags
 189  */
 190 #define EXT4_STATE_JDATA                0x00000001 /* journaled data exists */
 191 #define EXT4_STATE_NEW                  0x00000002 /* inode is newly created */
 192 #define EXT4_STATE_XATTR                0x00000004 /* has in-inode xattrs */
 193
 194 /* Used to pass group descriptor data when online resize is done */
 195 struct ext4_new_group_input {
 196         __u32 group;            /* Group number for this data */
 197         __u32 block_bitmap;     /* Absolute block number of block bitmap */
 198         __u32 inode_bitmap;     /* Absolute block number of inode bitmap */
 199         __u32 inode_table;      /* Absolute block number of inode table start */
 200         __u32 blocks_count;     /* Total number of blocks in this group */
 201         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
 202         __u16 unused;
 203 };
 204
 205 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 206 struct ext4_new_group_data {
 207         __u32 group;
 208         __u32 block_bitmap;
 209         __u32 inode_bitmap;
 210         __u32 inode_table;
 211         __u32 blocks_count;
 212         __u16 reserved_blocks;
 213         __u16 unused;
 214         __u32 free_blocks_count;
 215 };
 216
 217
 218 /*
 219  * ioctl commands
 220  */
 221 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
 222 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
 223 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
 224 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
 225 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
 226 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8,struct ext4_new_group_input)
 227 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
 228 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
 229 #ifdef CONFIG_JBD_DEBUG
 230 #define EXT4_IOC_WAIT_FOR_READONLY      _IOR('f', 99, long)
 231 #endif
 232 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
 233 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
 234
 235 /*
 236  * ioctl commands in 32 bit emulation
 237  */
 238 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
 239 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
 240 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
 241 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
 242 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
 243 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
 244 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
 245 #ifdef CONFIG_JBD_DEBUG
 246 #define EXT4_IOC32_WAIT_FOR_READONLY    _IOR('f', 99, int)
 247 #endif
 248 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
 249 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
 250
 251
 252 /*
 253  *  Mount options
 254  */
 255 struct ext4_mount_options {
 256         unsigned long s_mount_opt;
 257         uid_t s_resuid;
 258         gid_t s_resgid;
 259         unsigned long s_commit_interval;
 260 #ifdef CONFIG_QUOTA
 261         int s_jquota_fmt;
 262         char *s_qf_names[MAXQUOTAS];
 263 #endif
 264 };
 265
 266 /*
 267  * Structure of an inode on the disk
 268  */
 269 struct ext4_inode {
 270         __le16  i_mode;         /* File mode */
 271         __le16  i_uid;          /* Low 16 bits of Owner Uid */
 272         __le32  i_size;         /* Size in bytes */
 273         __le32  i_atime;        /* Access time */
 274         __le32  i_ctime;        /* Creation time */
 275         __le32  i_mtime;        /* Modification time */
 276         __le32  i_dtime;        /* Deletion Time */
 277         __le16  i_gid;          /* Low 16 bits of Group Id */
 278         __le16  i_links_count;  /* Links count */
 279         __le32  i_blocks;       /* Blocks count */
 280         __le32  i_flags;        /* File flags */
 281         union {
 282                 struct {
 283                         __u32  l_i_reserved1;
 284                 } linux1;
 285                 struct {
 286                         __u32  h_i_translator;
 287                 } hurd1;
 288                 struct {
 289                         __u32  m_i_reserved1;
 290                 } masix1;
 291         } osd1;                         /* OS dependent 1 */
 292         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 293         __le32  i_generation;   /* File version (for NFS) */
 294         __le32  i_file_acl;     /* File ACL */
 295         __le32  i_dir_acl;      /* Directory ACL */
 296         __le32  i_faddr;        /* Fragment address */
 297         union {
 298                 struct {
 299                         __u8    l_i_frag;       /* Fragment number */
 300                         __u8    l_i_fsize;      /* Fragment size */
 301                         __le16  l_i_file_acl_high;
 302                         __le16  l_i_uid_high;   /* these 2 fields    */
 303                         __le16  l_i_gid_high;   /* were reserved2[0] */
 304                         __u32   l_i_reserved2;
 305                 } linux2;
 306                 struct {
 307                         __u8    h_i_frag;       /* Fragment number */
 308                         __u8    h_i_fsize;      /* Fragment size */
 309                         __u16   h_i_mode_high;
 310                         __u16   h_i_uid_high;
 311                         __u16   h_i_gid_high;
 312                         __u32   h_i_author;
 313                 } hurd2;
 314                 struct {
 315                         __u8    m_i_frag;       /* Fragment number */
 316                         __u8    m_i_fsize;      /* Fragment size */
 317                         __le16  m_i_file_acl_high;
 318                         __u32   m_i_reserved2[2];
 319                 } masix2;
 320         } osd2;                         /* OS dependent 2 */
 321         __le16  i_extra_isize;
 322         __le16  i_pad1;
 323 };
 324
 325 #define i_size_high     i_dir_acl
 326
 327 #if defined(__KERNEL__) || defined(__linux__)
 328 #define i_reserved1     osd1.linux1.l_i_reserved1
 329 #define i_frag          osd2.linux2.l_i_frag
 330 #define i_fsize         osd2.linux2.l_i_fsize
 331 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
 332 #define i_uid_low       i_uid
 333 #define i_gid_low       i_gid
 334 #define i_uid_high      osd2.linux2.l_i_uid_high
 335 #define i_gid_high      osd2.linux2.l_i_gid_high
 336 #define i_reserved2     osd2.linux2.l_i_reserved2
 337
 338 #elif defined(__GNU__)
 339
 340 #define i_translator    osd1.hurd1.h_i_translator
 341 #define i_frag          osd2.hurd2.h_i_frag;
 342 #define i_fsize         osd2.hurd2.h_i_fsize;
 343 #define i_uid_high      osd2.hurd2.h_i_uid_high
 344 #define i_gid_high      osd2.hurd2.h_i_gid_high
 345 #define i_author        osd2.hurd2.h_i_author
 346
 347 #elif defined(__masix__)
 348
 349 #define i_reserved1     osd1.masix1.m_i_reserved1
 350 #define i_frag          osd2.masix2.m_i_frag
 351 #define i_fsize         osd2.masix2.m_i_fsize
 352 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
 353 #define i_reserved2     osd2.masix2.m_i_reserved2
 354
 355 #endif /* defined(__KERNEL__) || defined(__linux__) */
 356
 357 /*
 358  * File system states
 359  */
 360 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
 361 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
 362 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
 363
 364 /*
 365  * Mount flags
 366  */
 367 #define EXT4_MOUNT_CHECK                0x00001 /* Do mount-time checks */
 368 #define EXT4_MOUNT_OLDALLOC             0x00002  /* Don't use the new Orlov allocator */
 369 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
 370 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
 371 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
 372 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
 373 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
 374 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
 375 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
 376 #define EXT4_MOUNT_ABORT                0x00200 /* Fatal error detected */
 377 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
 378 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
 379 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
 380 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
 381 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
 382 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
 383 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
 384 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
 385 #define EXT4_MOUNT_RESERVATION          0x10000 /* Preallocation */
 386 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
 387 #define EXT4_MOUNT_NOBH                 0x40000 /* No bufferheads */
 388 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
 389 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
 390 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
 391 #define EXT4_MOUNT_EXTENTS              0x400000 /* Extents support */
 392
 393 /* Compatibility, for having both ext2_fs.h and ext4_fs.h included at once */
 394 #ifndef _LINUX_EXT2_FS_H
 395 #define clear_opt(o, opt)               o &= ~EXT4_MOUNT_##opt
 396 #define set_opt(o, opt)                 o |= EXT4_MOUNT_##opt
 397 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
 398                                          EXT4_MOUNT_##opt)
 399 #else
 400 #define EXT2_MOUNT_NOLOAD               EXT4_MOUNT_NOLOAD
 401 #define EXT2_MOUNT_ABORT                EXT4_MOUNT_ABORT
 402 #define EXT2_MOUNT_DATA_FLAGS           EXT4_MOUNT_DATA_FLAGS
 403 #endif
 404
 405 #define ext4_set_bit                    ext2_set_bit
 406 #define ext4_set_bit_atomic             ext2_set_bit_atomic
 407 #define ext4_clear_bit                  ext2_clear_bit
 408 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
 409 #define ext4_test_bit                   ext2_test_bit
 410 #define ext4_find_first_zero_bit        ext2_find_first_zero_bit
 411 #define ext4_find_next_zero_bit         ext2_find_next_zero_bit
 412
 413 /*
 414  * Maximal mount counts between two filesystem checks
 415  */
 416 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
 417 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
 418
 419 /*
 420  * Behaviour when detecting errors
 421  */
 422 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
 423 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
 424 #define EXT4_ERRORS_PANIC               3       /* Panic */
 425 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
 426
 427 /*
 428  * Structure of the super block
 429  */
 430 struct ext4_super_block {
 431 /*00*/  __le32  s_inodes_count;         /* Inodes count */
 432         __le32  s_blocks_count;         /* Blocks count */
 433         __le32  s_r_blocks_count;       /* Reserved blocks count */
 434         __le32  s_free_blocks_count;    /* Free blocks count */
 435 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
 436         __le32  s_first_data_block;     /* First Data Block */
 437         __le32  s_log_block_size;       /* Block size */
 438         __le32  s_log_frag_size;        /* Fragment size */
 439 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
 440         __le32  s_frags_per_group;      /* # Fragments per group */
 441         __le32  s_inodes_per_group;     /* # Inodes per group */
 442         __le32  s_mtime;                /* Mount time */
 443 /*30*/  __le32  s_wtime;                /* Write time */
 444         __le16  s_mnt_count;            /* Mount count */
 445         __le16  s_max_mnt_count;        /* Maximal mount count */
 446         __le16  s_magic;                /* Magic signature */
 447         __le16  s_state;                /* File system state */
 448         __le16  s_errors;               /* Behaviour when detecting errors */
 449         __le16  s_minor_rev_level;      /* minor revision level */
 450 /*40*/  __le32  s_lastcheck;            /* time of last check */
 451         __le32  s_checkinterval;        /* max. time between checks */
 452         __le32  s_creator_os;           /* OS */
 453         __le32  s_rev_level;            /* Revision level */
 454 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
 455         __le16  s_def_resgid;           /* Default gid for reserved blocks */
 456         /*
 457          * These fields are for EXT4_DYNAMIC_REV superblocks only.
 458          *
 459          * Note: the difference between the compatible feature set and
 460          * the incompatible feature set is that if there is a bit set
 461          * in the incompatible feature set that the kernel doesn't
 462          * know about, it should refuse to mount the filesystem.
 463          *
 464          * e2fsck's requirements are more strict; if it doesn't know
 465          * about a feature in either the compatible or incompatible
 466          * feature set, it must abort and not try to meddle with
 467          * things it doesn't understand...
 468          */
 469         __le32  s_first_ino;            /* First non-reserved inode */
 470         __le16   s_inode_size;          /* size of inode structure */
 471         __le16  s_block_group_nr;       /* block group # of this superblock */
 472         __le32  s_feature_compat;       /* compatible feature set */
 473 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
 474         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
 475 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
 476 /*78*/  char    s_volume_name[16];      /* volume name */
 477 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
 478 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
 479         /*
 480          * Performance hints.  Directory preallocation should only
 481          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
 482          */
 483         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
 484         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
 485         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
 486         /*
 487          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
 488          */
 489 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
 490 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
 491         __le32  s_journal_dev;          /* device number of journal file */
 492         __le32  s_last_orphan;          /* start of list of inodes to delete */
 493         __le32  s_hash_seed[4];         /* HTREE hash seed */
 494         __u8    s_def_hash_version;     /* Default hash version to use */
 495         __u8    s_reserved_char_pad;
 496         __u16   s_reserved_word_pad;
 497         __le32  s_default_mount_opts;
 498         __le32  s_first_meta_bg;        /* First metablock block group */
 499         __u32   s_reserved[190];        /* Padding to the end of the block */
 500 };
 501
 502 #ifdef __KERNEL__
 503 #include <linux/ext4_fs_i.h>
 504 #include <linux/ext4_fs_sb.h>
 505 static inline struct ext4_sb_info * EXT4_SB(struct super_block *sb)
 506 {
 507         return sb->s_fs_info;
 508 }
 509 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
 510 {
 511         return container_of(inode, struct ext4_inode_info, vfs_inode);
 512 }
 513
 514 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
 515 {
 516         return ino == EXT4_ROOT_INO ||
 517                 ino == EXT4_JOURNAL_INO ||
 518                 ino == EXT4_RESIZE_INO ||
 519                 (ino >= EXT4_FIRST_INO(sb) &&
 520                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
 521 }
 522 #else
 523 /* Assume that user mode programs are passing in an ext4fs superblock, not
 524  * a kernel struct super_block.  This will allow us to call the feature-test
 525  * macros from user land. */
 526 #define EXT4_SB(sb)     (sb)
 527 #endif
 528
 529 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
 530
 531 /*
 532  * Codes for operating systems
 533  */
 534 #define EXT4_OS_LINUX           0
 535 #define EXT4_OS_HURD            1
 536 #define EXT4_OS_MASIX           2
 537 #define EXT4_OS_FREEBSD         3
 538 #define EXT4_OS_LITES           4
 539
 540 /*
 541  * Revision levels
 542  */
 543 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
 544 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
 545
 546 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
 547 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
 548
 549 #define EXT4_GOOD_OLD_INODE_SIZE 128
 550
 551 /*
 552  * Feature set definitions
 553  */
 554
 555 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
 556         ( EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )
 557 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
 558         ( EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )
 559 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
 560         ( EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )
 561 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
 562         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
 563 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
 564         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
 565 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
 566         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
 567 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
 568         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
 569 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
 570         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
 571 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
 572         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
 573
 574 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
 575 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
 576 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
 577 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
 578 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
 579 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
 580
 581 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
 582 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
 583 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
 584
 585 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
 586 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
 587 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
 588 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
 589 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
 590 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
 591
 592 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
 593 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
 594                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
 595                                          EXT4_FEATURE_INCOMPAT_META_BG| \
 596                                          EXT4_FEATURE_INCOMPAT_EXTENTS)
 597 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
 598                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
 599                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR)
 600
 601 /*
 602  * Default values for user and/or group using reserved blocks
 603  */
 604 #define EXT4_DEF_RESUID         0
 605 #define EXT4_DEF_RESGID         0
 606
 607 /*
 608  * Default mount options
 609  */
 610 #define EXT4_DEFM_DEBUG         0x0001
 611 #define EXT4_DEFM_BSDGROUPS     0x0002
 612 #define EXT4_DEFM_XATTR_USER    0x0004
 613 #define EXT4_DEFM_ACL           0x0008
 614 #define EXT4_DEFM_UID16         0x0010
 615 #define EXT4_DEFM_JMODE         0x0060
 616 #define EXT4_DEFM_JMODE_DATA    0x0020
 617 #define EXT4_DEFM_JMODE_ORDERED 0x0040
 618 #define EXT4_DEFM_JMODE_WBACK   0x0060
 619
 620 /*
 621  * Structure of a directory entry
 622  */
 623 #define EXT4_NAME_LEN 255
 624
 625 struct ext4_dir_entry {
 626         __le32  inode;                  /* Inode number */
 627         __le16  rec_len;                /* Directory entry length */
 628         __le16  name_len;               /* Name length */
 629         char    name[EXT4_NAME_LEN];    /* File name */
 630 };
 631
 632 /*
 633  * The new version of the directory entry.  Since EXT4 structures are
 634  * stored in intel byte order, and the name_len field could never be
 635  * bigger than 255 chars, it's safe to reclaim the extra byte for the
 636  * file_type field.
 637  */
 638 struct ext4_dir_entry_2 {
 639         __le32  inode;                  /* Inode number */
 640         __le16  rec_len;                /* Directory entry length */
 641         __u8    name_len;               /* Name length */
 642         __u8    file_type;
 643         char    name[EXT4_NAME_LEN];    /* File name */
 644 };
 645
 646 /*
 647  * Ext4 directory file types.  Only the low 3 bits are used.  The
 648  * other bits are reserved for now.
 649  */
 650 #define EXT4_FT_UNKNOWN         0
 651 #define EXT4_FT_REG_FILE        1
 652 #define EXT4_FT_DIR             2
 653 #define EXT4_FT_CHRDEV          3
 654 #define EXT4_FT_BLKDEV          4
 655 #define EXT4_FT_FIFO            5
 656 #define EXT4_FT_SOCK            6
 657 #define EXT4_FT_SYMLINK         7
 658
 659 #define EXT4_FT_MAX             8
 660
 661 /*
 662  * EXT4_DIR_PAD defines the directory entries boundaries
 663  *
 664  * NOTE: It must be a multiple of 4
 665  */
 666 #define EXT4_DIR_PAD                    4
 667 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
 668 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
 669                                          ~EXT4_DIR_ROUND)
 670 /*
 671  * Hash Tree Directory indexing
 672  * (c) Daniel Phillips, 2001
 673  */
 674
 675 #ifdef CONFIG_EXT4_INDEX
 676   #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
 677                                               EXT4_FEATURE_COMPAT_DIR_INDEX) && \
 678                       (EXT4_I(dir)->i_flags & EXT4_INDEX_FL))
 679 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
 680 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
 681 #else
 682   #define is_dx(dir) 0
 683 #define EXT4_DIR_LINK_MAX(dir) ((dir)->i_nlink >= EXT4_LINK_MAX)
 684 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2)
 685 #endif
 686
 687 /* Legal values for the dx_root hash_version field: */
 688
 689 #define DX_HASH_LEGACY          0
 690 #define DX_HASH_HALF_MD4        1
 691 #define DX_HASH_TEA             2
 692
 693 #ifdef __KERNEL__
 694
 695 /* hash info structure used by the directory hash */
 696 struct dx_hash_info
 697 {
 698         u32             hash;
 699         u32             minor_hash;
 700         int             hash_version;
 701         u32             *seed;
 702 };
 703
 704 #define EXT4_HTREE_EOF  0x7fffffff
 705
 706 /*
 707  * Control parameters used by ext4_htree_next_block
 708  */
 709 #define HASH_NB_ALWAYS          1
 710
 711
 712 /*
 713  * Describe an inode's exact location on disk and in memory
 714  */
 715 struct ext4_iloc
 716 {
 717         struct buffer_head *bh;
 718         unsigned long offset;
 719         unsigned long block_group;
 720 };
 721
 722 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
 723 {
 724         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
 725 }
 726
 727 /*
 728  * This structure is stuffed into the struct file's private_data field
 729  * for directories.  It is where we put information so that we can do
 730  * readdir operations in hash tree order.
 731  */
 732 struct dir_private_info {
 733         struct rb_root  root;
 734         struct rb_node  *curr_node;
 735         struct fname    *extra_fname;
 736         loff_t          last_pos;
 737         __u32           curr_hash;
 738         __u32           curr_minor_hash;
 739         __u32           next_hash;
 740 };
 741
 742 /* calculate the first block number of the group */
 743 static inline ext4_fsblk_t
 744 ext4_group_first_block_no(struct super_block *sb, unsigned long group_no)
 745 {
 746         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
 747                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
 748 }
 749
 750 /*
 751  * Special error return code only used by dx_probe() and its callers.
 752  */
 753 #define ERR_BAD_DX_DIR  -75000
 754
 755 /*
 756  * This function calculate the block group number and offset,
 757  * given a block number
 758  */
 759
 760 static inline void ext4_get_group_no_and_offset(struct super_block * sb,
 761                                 ext4_fsblk_t blocknr, unsigned long* blockgrpp,
 762                                 ext4_grpblk_t *offsetp)
 763 {
 764         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 765         ext4_grpblk_t offset;
 766
 767         blocknr = blocknr - le32_to_cpu(es->s_first_data_block);
 768         offset = sector_div(blocknr, EXT4_BLOCKS_PER_GROUP(sb));
 769         if (offsetp)
 770                 *offsetp = offset;
 771         if (blockgrpp)
 772                 *blockgrpp = blocknr;
 773
 774 }
 775
 776 /*
 777  * Function prototypes
 778  */
 779
 780 /*
 781  * Ok, these declarations are also in <linux/kernel.h> but none of the
 782  * ext4 source programs needs to include it so they are duplicated here.
 783  */
 784 # define NORET_TYPE    /**/
 785 # define ATTRIB_NORET  __attribute__((noreturn))
 786 # define NORET_AND     noreturn,
 787
 788 /* balloc.c */
 789 extern unsigned int ext4_block_group(struct super_block *sb,
 790                         ext4_fsblk_t blocknr);
 791 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
 792                         ext4_fsblk_t blocknr);
 793 extern int ext4_bg_has_super(struct super_block *sb, int group);
 794 extern unsigned long ext4_bg_num_gdb(struct super_block *sb, int group);
 795 extern ext4_fsblk_t ext4_new_block (handle_t *handle, struct inode *inode,
 796                         ext4_fsblk_t goal, int *errp);
 797 extern ext4_fsblk_t ext4_new_blocks (handle_t *handle, struct inode *inode,
 798                         ext4_fsblk_t goal, unsigned long *count, int *errp);
 799 extern void ext4_free_blocks (handle_t *handle, struct inode *inode,
 800                         ext4_fsblk_t block, unsigned long count);
 801 extern void ext4_free_blocks_sb (handle_t *handle, struct super_block *sb,
 802                                  ext4_fsblk_t block, unsigned long count,
 803                                 unsigned long *pdquot_freed_blocks);
 804 extern ext4_fsblk_t ext4_count_free_blocks (struct super_block *);
 805 extern void ext4_check_blocks_bitmap (struct super_block *);
 806 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
 807                                                     unsigned int block_group,
 808                                                     struct buffer_head ** bh);
 809 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
 810 extern void ext4_init_block_alloc_info(struct inode *);
 811 extern void ext4_rsv_window_add(struct super_block *sb, struct ext4_reserve_window_node *rsv);
 812
 813 /* dir.c */
 814 extern int ext4_check_dir_entry(const char *, struct inode *,
 815                                 struct ext4_dir_entry_2 *,
 816                                 struct buffer_head *, unsigned long);
 817 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
 818                                     __u32 minor_hash,
 819                                     struct ext4_dir_entry_2 *dirent);
 820 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
 821
 822 /* fsync.c */
 823 extern int ext4_sync_file (struct file *, struct dentry *, int);
 824
 825 /* hash.c */
 826 extern int ext4fs_dirhash(const char *name, int len, struct
 827                           dx_hash_info *hinfo);
 828
 829 /* ialloc.c */
 830 extern struct inode * ext4_new_inode (handle_t *, struct inode *, int);
 831 extern void ext4_free_inode (handle_t *, struct inode *);
 832 extern struct inode * ext4_orphan_get (struct super_block *, unsigned long);
 833 extern unsigned long ext4_count_free_inodes (struct super_block *);
 834 extern unsigned long ext4_count_dirs (struct super_block *);
 835 extern void ext4_check_inodes_bitmap (struct super_block *);
 836 extern unsigned long ext4_count_free (struct buffer_head *, unsigned);
 837
 838
 839 /* inode.c */
 840 int ext4_forget(handle_t *handle, int is_metadata, struct inode *inode,
 841                 struct buffer_head *bh, ext4_fsblk_t blocknr);
 842 struct buffer_head * ext4_getblk (handle_t *, struct inode *, long, int, int *);
 843 struct buffer_head * ext4_bread (handle_t *, struct inode *, int, int, int *);
 844 int ext4_get_blocks_handle(handle_t *handle, struct inode *inode,
 845         sector_t iblock, unsigned long maxblocks, struct buffer_head *bh_result,
 846         int create, int extend_disksize);
 847
 848 extern void ext4_read_inode (struct inode *);
 849 extern int  ext4_write_inode (struct inode *, int);
 850 extern int  ext4_setattr (struct dentry *, struct iattr *);
 851 extern void ext4_delete_inode (struct inode *);
 852 extern int  ext4_sync_inode (handle_t *, struct inode *);
 853 extern void ext4_discard_reservation (struct inode *);
 854 extern void ext4_dirty_inode(struct inode *);
 855 extern int ext4_change_inode_journal_flag(struct inode *, int);
 856 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
 857 extern void ext4_truncate (struct inode *);
 858 extern void ext4_set_inode_flags(struct inode *);
 859 extern void ext4_set_aops(struct inode *inode);
 860 extern int ext4_writepage_trans_blocks(struct inode *);
 861 extern int ext4_block_truncate_page(handle_t *handle, struct page *page,
 862                 struct address_space *mapping, loff_t from);
 863
 864 /* ioctl.c */
 865 extern int ext4_ioctl (struct inode *, struct file *, unsigned int,
 866                        unsigned long);
 867 extern long ext4_compat_ioctl (struct file *, unsigned int, unsigned long);
 868
 869 /* namei.c */
 870 extern int ext4_orphan_add(handle_t *, struct inode *);
 871 extern int ext4_orphan_del(handle_t *, struct inode *);
 872 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
 873                                 __u32 start_minor_hash, __u32 *next_hash);
 874
 875 /* resize.c */
 876 extern int ext4_group_add(struct super_block *sb,
 877                                 struct ext4_new_group_data *input);
 878 extern int ext4_group_extend(struct super_block *sb,
 879                                 struct ext4_super_block *es,
 880                                 ext4_fsblk_t n_blocks_count);
 881
 882 /* super.c */
 883 extern void ext4_error (struct super_block *, const char *, const char *, ...)
 884         __attribute__ ((format (printf, 3, 4)));
 885 extern void __ext4_std_error (struct super_block *, const char *, int);
 886 extern void ext4_abort (struct super_block *, const char *, const char *, ...)
 887         __attribute__ ((format (printf, 3, 4)));
 888 extern void ext4_warning (struct super_block *, const char *, const char *, ...)
 889         __attribute__ ((format (printf, 3, 4)));
 890 extern void ext4_update_dynamic_rev (struct super_block *sb);
 891
 892 #define ext4_std_error(sb, errno)                               \
 893 do {                                                            \
 894         if ((errno))                                            \
 895                 __ext4_std_error((sb), __FUNCTION__, (errno));  \
 896 } while (0)
 897
 898 /*
 899  * Inodes and files operations
 900  */
 901
 902 /* dir.c */
 903 extern const struct file_operations ext4_dir_operations;
 904
 905 /* file.c */
 906 extern struct inode_operations ext4_file_inode_operations;
 907 extern const struct file_operations ext4_file_operations;
 908
 909 /* namei.c */
 910 extern struct inode_operations ext4_dir_inode_operations;
 911 extern struct inode_operations ext4_special_inode_operations;
 912
 913 /* symlink.c */
 914 extern struct inode_operations ext4_symlink_inode_operations;
 915 extern struct inode_operations ext4_fast_symlink_inode_operations;
 916
 917 /* extents.c */
 918 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
 919 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
 920 extern int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 921                         ext4_fsblk_t iblock,
 922                         unsigned long max_blocks, struct buffer_head *bh_result,
 923                         int create, int extend_disksize);
 924 extern void ext4_ext_truncate(struct inode *, struct page *);
 925 extern void ext4_ext_init(struct super_block *);
 926 extern void ext4_ext_release(struct super_block *);
 927 static inline int
 928 ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block,
 929                         unsigned long max_blocks, struct buffer_head *bh,
 930                         int create, int extend_disksize)
 931 {
 932         if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)
 933                 return ext4_ext_get_blocks(handle, inode, block, max_blocks,
 934                                         bh, create, extend_disksize);
 935         return ext4_get_blocks_handle(handle, inode, block, max_blocks, bh,
 936                                         create, extend_disksize);
 937 }
 938
 939
 940 #endif  /* __KERNEL__ */
 941
 942 #endif  /* _LINUX_EXT4_FS_H */