include/linux/ext2_fs.h

   1 /*
   2  *  linux/include/linux/ext2_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_EXT2_FS_H
  17 #define _LINUX_EXT2_FS_H
  18
  19 #include <linux/types.h>
  20
  21 /*
  22  * The second extended filesystem constants/structures
  23  */
  24
  25 /*
  26  * Define EXT2FS_DEBUG to produce debug messages
  27  */
  28 #undef EXT2FS_DEBUG
  29
  30 /*
  31  * Define EXT2_PREALLOCATE to preallocate data blocks for expanding files
  32  */
  33 #define EXT2_PREALLOCATE
  34 #define EXT2_DEFAULT_PREALLOC_BLOCKS    8
  35
  36 /*
  37  * The second extended file system version
  38  */
  39 #define EXT2FS_DATE             "95/08/09"
  40 #define EXT2FS_VERSION          "0.5b"
  41
  42 /*
  43  * Debug code
  44  */
  45 #ifdef EXT2FS_DEBUG
  46 #       define ext2_debug(f, a...)      { \
  47                                         printk ("EXT2-fs DEBUG (%s, %d): %s:", \
  48                                                 __FILE__, __LINE__, __FUNCTION__); \
  49                                         printk (f, ## a); \
  50                                         }
  51 #else
  52 #       define ext2_debug(f, a...)      /**/
  53 #endif
  54
  55 /*
  56  * Special inodes numbers
  57  */
  58 #define EXT2_BAD_INO             1      /* Bad blocks inode */
  59 #define EXT2_ROOT_INO            2      /* Root inode */
  60 #define EXT2_ACL_IDX_INO         3      /* ACL inode */
  61 #define EXT2_ACL_DATA_INO        4      /* ACL inode */
  62 #define EXT2_BOOT_LOADER_INO     5      /* Boot loader inode */
  63 #define EXT2_UNDEL_DIR_INO       6      /* Undelete directory inode */
  64
  65 /* First non-reserved inode for old ext2 filesystems */
  66 #define EXT2_GOOD_OLD_FIRST_INO 11
  67
  68 /*
  69  * The second extended file system magic number
  70  */
  71 #define EXT2_SUPER_MAGIC        0xEF53
  72
  73 /*
  74  * Maximal count of links to a file
  75  */
  76 #define EXT2_LINK_MAX           32000
  77
  78 /*
  79  * Macro-instructions used to manage several block sizes
  80  */
  81 #define EXT2_MIN_BLOCK_SIZE             1024
  82 #define EXT2_MAX_BLOCK_SIZE             4096
  83 #define EXT2_MIN_BLOCK_LOG_SIZE           10
  84 #ifdef __KERNEL__
  85 # define EXT2_BLOCK_SIZE(s)             ((s)->s_blocksize)
  86 #else
  87 # define EXT2_BLOCK_SIZE(s)             (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
  88 #endif
  89 #define EXT2_ACLE_PER_BLOCK(s)          (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_acl_entry))
  90 #define EXT2_ADDR_PER_BLOCK(s)          (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
  91 #ifdef __KERNEL__
  92 # define EXT2_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
  93 #else
  94 # define EXT2_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
  95 #endif
  96 #ifdef __KERNEL__
  97 #define EXT2_ADDR_PER_BLOCK_BITS(s)     ((s)->u.ext2_sb.s_addr_per_block_bits)
  98 #define EXT2_INODE_SIZE(s)              ((s)->u.ext2_sb.s_inode_size)
  99 #define EXT2_FIRST_INO(s)               ((s)->u.ext2_sb.s_first_ino)
 100 #else
 101 #define EXT2_INODE_SIZE(s)      (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
 102                                  EXT2_GOOD_OLD_INODE_SIZE : \
 103                                  (s)->s_inode_size)
 104 #define EXT2_FIRST_INO(s)       (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
 105                                  EXT2_GOOD_OLD_FIRST_INO : \
 106                                  (s)->s_first_ino)
 107 #endif
 108
 109 /*
 110  * Macro-instructions used to manage fragments
 111  */
 112 #define EXT2_MIN_FRAG_SIZE              1024
 113 #define EXT2_MAX_FRAG_SIZE              4096
 114 #define EXT2_MIN_FRAG_LOG_SIZE            10
 115 #ifdef __KERNEL__
 116 # define EXT2_FRAG_SIZE(s)              ((s)->u.ext2_sb.s_frag_size)
 117 # define EXT2_FRAGS_PER_BLOCK(s)        ((s)->u.ext2_sb.s_frags_per_block)
 118 #else
 119 # define EXT2_FRAG_SIZE(s)              (EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
 120 # define EXT2_FRAGS_PER_BLOCK(s)        (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
 121 #endif
 122
 123 /*
 124  * ACL structures
 125  */
 126 struct ext2_acl_header  /* Header of Access Control Lists */
 127 {
 128         __u32   aclh_size;
 129         __u32   aclh_file_count;
 130         __u32   aclh_acle_count;
 131         __u32   aclh_first_acle;
 132 };
 133
 134 struct ext2_acl_entry   /* Access Control List Entry */
 135 {
 136         __u32   acle_size;
 137         __u16   acle_perms;     /* Access permissions */
 138         __u16   acle_type;      /* Type of entry */
 139         __u16   acle_tag;       /* User or group identity */
 140         __u16   acle_pad1;
 141         __u32   acle_next;      /* Pointer on next entry for the */
 142                                         /* same inode or on next free entry */
 143 };
 144
 145 /*
 146  * Structure of a blocks group descriptor
 147  */
 148 struct ext2_group_desc
 149 {
 150         __u32   bg_block_bitmap;                /* Blocks bitmap block */
 151         __u32   bg_inode_bitmap;                /* Inodes bitmap block */
 152         __u32   bg_inode_table;         /* Inodes table block */
 153         __u16   bg_free_blocks_count;   /* Free blocks count */
 154         __u16   bg_free_inodes_count;   /* Free inodes count */
 155         __u16   bg_used_dirs_count;     /* Directories count */
 156         __u16   bg_pad;
 157         __u32   bg_reserved[3];
 158 };
 159
 160 /*
 161  * Macro-instructions used to manage group descriptors
 162  */
 163 #ifdef __KERNEL__
 164 # define EXT2_BLOCKS_PER_GROUP(s)       ((s)->u.ext2_sb.s_blocks_per_group)
 165 # define EXT2_DESC_PER_BLOCK(s)         ((s)->u.ext2_sb.s_desc_per_block)
 166 # define EXT2_INODES_PER_GROUP(s)       ((s)->u.ext2_sb.s_inodes_per_group)
 167 # define EXT2_DESC_PER_BLOCK_BITS(s)    ((s)->u.ext2_sb.s_desc_per_block_bits)
 168 #else
 169 # define EXT2_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 170 # define EXT2_DESC_PER_BLOCK(s)         (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
 171 # define EXT2_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 172 #endif
 173
 174 /*
 175  * Constants relative to the data blocks
 176  */
 177 #define EXT2_NDIR_BLOCKS                12
 178 #define EXT2_IND_BLOCK                  EXT2_NDIR_BLOCKS
 179 #define EXT2_DIND_BLOCK                 (EXT2_IND_BLOCK + 1)
 180 #define EXT2_TIND_BLOCK                 (EXT2_DIND_BLOCK + 1)
 181 #define EXT2_N_BLOCKS                   (EXT2_TIND_BLOCK + 1)
 182
 183 /*
 184  * Inode flags
 185  */
 186 #define EXT2_SECRM_FL                   0x00000001 /* Secure deletion */
 187 #define EXT2_UNRM_FL                    0x00000002 /* Undelete */
 188 #define EXT2_COMPR_FL                   0x00000004 /* Compress file */
 189 #define EXT2_SYNC_FL                    0x00000008 /* Synchronous updates */
 190 #define EXT2_IMMUTABLE_FL               0x00000010 /* Immutable file */
 191 #define EXT2_APPEND_FL                  0x00000020 /* writes to file may only append */
 192 #define EXT2_NODUMP_FL                  0x00000040 /* do not dump file */
 193 #define EXT2_NOATIME_FL                 0x00000080 /* do not update atime */
 194 /* Reserved for compression usage... */
 195 #define EXT2_DIRTY_FL                   0x00000100
 196 #define EXT2_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 197 #define EXT2_NOCOMP_FL                  0x00000400 /* Don't compress */
 198 #define EXT2_ECOMPR_FL                  0x00000800 /* Compression error */
 199 /* End compression flags --- maybe not all used */
 200 #define EXT2_BTREE_FL                   0x00001000 /* btree format dir */
 201 #define EXT2_RESERVED_FL                0x80000000 /* reserved for ext2 lib */
 202
 203 #define EXT2_FL_USER_VISIBLE            0x00001FFF /* User visible flags */
 204 #define EXT2_FL_USER_MODIFIABLE         0x000000FF /* User modifiable flags */
 205
 206 /*
 207  * ioctl commands
 208  */
 209 #define EXT2_IOC_GETFLAGS               _IOR('f', 1, long)
 210 #define EXT2_IOC_SETFLAGS               _IOW('f', 2, long)
 211 #define EXT2_IOC_GETVERSION             _IOR('v', 1, long)
 212 #define EXT2_IOC_SETVERSION             _IOW('v', 2, long)
 213
 214 /*
 215  * Structure of an inode on the disk
 216  */
 217 struct ext2_inode {
 218         __u16   i_mode;         /* File mode */
 219         __u16   i_uid;          /* Low 16 bits of Owner Uid */
 220         __u32   i_size;         /* Size in bytes */
 221         __u32   i_atime;        /* Access time */
 222         __u32   i_ctime;        /* Creation time */
 223         __u32   i_mtime;        /* Modification time */
 224         __u32   i_dtime;        /* Deletion Time */
 225         __u16   i_gid;          /* Low 16 bits of Group Id */
 226         __u16   i_links_count;  /* Links count */
 227         __u32   i_blocks;       /* Blocks count */
 228         __u32   i_flags;        /* File flags */
 229         union {
 230                 struct {
 231                         __u32  l_i_reserved1;
 232                 } linux1;
 233                 struct {
 234                         __u32  h_i_translator;
 235                 } hurd1;
 236                 struct {
 237                         __u32  m_i_reserved1;
 238                 } masix1;
 239         } osd1;                         /* OS dependent 1 */
 240         __u32   i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
 241         __u32   i_generation;   /* File version (for NFS) */
 242         __u32   i_file_acl;     /* File ACL */
 243         __u32   i_dir_acl;      /* Directory ACL */
 244         __u32   i_faddr;        /* Fragment address */
 245         union {
 246                 struct {
 247                         __u8    l_i_frag;       /* Fragment number */
 248                         __u8    l_i_fsize;      /* Fragment size */
 249                         __u16   i_pad1;
 250                         __u16   l_i_uid_high;   /* these 2 fields    */
 251                         __u16   l_i_gid_high;   /* were reserved2[0] */
 252                         __u32   l_i_reserved2;
 253                 } linux2;
 254                 struct {
 255                         __u8    h_i_frag;       /* Fragment number */
 256                         __u8    h_i_fsize;      /* Fragment size */
 257                         __u16   h_i_mode_high;
 258                         __u16   h_i_uid_high;
 259                         __u16   h_i_gid_high;
 260                         __u32   h_i_author;
 261                 } hurd2;
 262                 struct {
 263                         __u8    m_i_frag;       /* Fragment number */
 264                         __u8    m_i_fsize;      /* Fragment size */
 265                         __u16   m_pad1;
 266                         __u32   m_i_reserved2[2];
 267                 } masix2;
 268         } osd2;                         /* OS dependent 2 */
 269 };
 270
 271 #define i_size_high     i_dir_acl
 272
 273 #if defined(__KERNEL__) || defined(__linux__)
 274 #define i_reserved1     osd1.linux1.l_i_reserved1
 275 #define i_frag          osd2.linux2.l_i_frag
 276 #define i_fsize         osd2.linux2.l_i_fsize
 277 #define i_uid_low       i_uid
 278 #define i_gid_low       i_gid
 279 #define i_uid_high      osd2.linux2.l_i_uid_high
 280 #define i_gid_high      osd2.linux2.l_i_gid_high
 281 #define i_reserved2     osd2.linux2.l_i_reserved2
 282 #endif
 283
 284 #ifdef  __hurd__
 285 #define i_translator    osd1.hurd1.h_i_translator
 286 #define i_frag          osd2.hurd2.h_i_frag;
 287 #define i_fsize         osd2.hurd2.h_i_fsize;
 288 #define i_uid_high      osd2.hurd2.h_i_uid_high
 289 #define i_gid_high      osd2.hurd2.h_i_gid_high
 290 #define i_author        osd2.hurd2.h_i_author
 291 #endif
 292
 293 #ifdef  __masix__
 294 #define i_reserved1     osd1.masix1.m_i_reserved1
 295 #define i_frag          osd2.masix2.m_i_frag
 296 #define i_fsize         osd2.masix2.m_i_fsize
 297 #define i_reserved2     osd2.masix2.m_i_reserved2
 298 #endif
 299
 300 /*
 301  * File system states
 302  */
 303 #define EXT2_VALID_FS                   0x0001  /* Unmounted cleanly */
 304 #define EXT2_ERROR_FS                   0x0002  /* Errors detected */
 305
 306 /*
 307  * Mount flags
 308  */
 309 #define EXT2_MOUNT_CHECK                0x0001  /* Do mount-time checks */
 310 #define EXT2_MOUNT_GRPID                0x0004  /* Create files with directory's group */
 311 #define EXT2_MOUNT_DEBUG                0x0008  /* Some debugging messages */
 312 #define EXT2_MOUNT_ERRORS_CONT          0x0010  /* Continue on errors */
 313 #define EXT2_MOUNT_ERRORS_RO            0x0020  /* Remount fs ro on errors */
 314 #define EXT2_MOUNT_ERRORS_PANIC         0x0040  /* Panic on errors */
 315 #define EXT2_MOUNT_MINIX_DF             0x0080  /* Mimics the Minix statfs */
 316 #define EXT2_MOUNT_NO_UID32             0x0200  /* Disable 32-bit UIDs */
 317
 318 #define clear_opt(o, opt)               o &= ~EXT2_MOUNT_##opt
 319 #define set_opt(o, opt)                 o |= EXT2_MOUNT_##opt
 320 #define test_opt(sb, opt)               ((sb)->u.ext2_sb.s_mount_opt & \
 321                                          EXT2_MOUNT_##opt)
 322 /*
 323  * Maximal mount counts between two filesystem checks
 324  */
 325 #define EXT2_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
 326 #define EXT2_DFL_CHECKINTERVAL          0       /* Don't use interval check */
 327
 328 /*
 329  * Behaviour when detecting errors
 330  */
 331 #define EXT2_ERRORS_CONTINUE            1       /* Continue execution */
 332 #define EXT2_ERRORS_RO                  2       /* Remount fs read-only */
 333 #define EXT2_ERRORS_PANIC               3       /* Panic */
 334 #define EXT2_ERRORS_DEFAULT             EXT2_ERRORS_CONTINUE
 335
 336 /*
 337  * Structure of the super block
 338  */
 339 struct ext2_super_block {
 340         __u32   s_inodes_count;         /* Inodes count */
 341         __u32   s_blocks_count;         /* Blocks count */
 342         __u32   s_r_blocks_count;       /* Reserved blocks count */
 343         __u32   s_free_blocks_count;    /* Free blocks count */
 344         __u32   s_free_inodes_count;    /* Free inodes count */
 345         __u32   s_first_data_block;     /* First Data Block */
 346         __u32   s_log_block_size;       /* Block size */
 347         __s32   s_log_frag_size;        /* Fragment size */
 348         __u32   s_blocks_per_group;     /* # Blocks per group */
 349         __u32   s_frags_per_group;      /* # Fragments per group */
 350         __u32   s_inodes_per_group;     /* # Inodes per group */
 351         __u32   s_mtime;                /* Mount time */
 352         __u32   s_wtime;                /* Write time */
 353         __u16   s_mnt_count;            /* Mount count */
 354         __s16   s_max_mnt_count;        /* Maximal mount count */
 355         __u16   s_magic;                /* Magic signature */
 356         __u16   s_state;                /* File system state */
 357         __u16   s_errors;               /* Behaviour when detecting errors */
 358         __u16   s_minor_rev_level;      /* minor revision level */
 359         __u32   s_lastcheck;            /* time of last check */
 360         __u32   s_checkinterval;        /* max. time between checks */
 361         __u32   s_creator_os;           /* OS */
 362         __u32   s_rev_level;            /* Revision level */
 363         __u16   s_def_resuid;           /* Default uid for reserved blocks */
 364         __u16   s_def_resgid;           /* Default gid for reserved blocks */
 365         /*
 366          * These fields are for EXT2_DYNAMIC_REV superblocks only.
 367          *
 368          * Note: the difference between the compatible feature set and
 369          * the incompatible feature set is that if there is a bit set
 370          * in the incompatible feature set that the kernel doesn't
 371          * know about, it should refuse to mount the filesystem.
 372          *
 373          * e2fsck's requirements are more strict; if it doesn't know
 374          * about a feature in either the compatible or incompatible
 375          * feature set, it must abort and not try to meddle with
 376          * things it doesn't understand...
 377          */
 378         __u32   s_first_ino;            /* First non-reserved inode */
 379         __u16   s_inode_size;           /* size of inode structure */
 380         __u16   s_block_group_nr;       /* block group # of this superblock */
 381         __u32   s_feature_compat;       /* compatible feature set */
 382         __u32   s_feature_incompat;     /* incompatible feature set */
 383         __u32   s_feature_ro_compat;    /* readonly-compatible feature set */
 384         __u8    s_uuid[16];             /* 128-bit uuid for volume */
 385         char    s_volume_name[16];      /* volume name */
 386         char    s_last_mounted[64];     /* directory where last mounted */
 387         __u32   s_algorithm_usage_bitmap; /* For compression */
 388         /*
 389          * Performance hints.  Directory preallocation should only
 390          * happen if the EXT2_COMPAT_PREALLOC flag is on.
 391          */
 392         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
 393         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
 394         __u16   s_padding1;
 395         __u32   s_reserved[204];        /* Padding to the end of the block */
 396 };
 397
 398 #ifdef __KERNEL__
 399 #define EXT2_SB(sb)     (&((sb)->u.ext2_sb))
 400 #else
 401 /* Assume that user mode programs are passing in an ext2fs superblock, not
 402  * a kernel struct super_block.  This will allow us to call the feature-test
 403  * macros from user land. */
 404 #define EXT2_SB(sb)     (sb)
 405 #endif
 406
 407 /*
 408  * Codes for operating systems
 409  */
 410 #define EXT2_OS_LINUX           0
 411 #define EXT2_OS_HURD            1
 412 #define EXT2_OS_MASIX           2
 413 #define EXT2_OS_FREEBSD         3
 414 #define EXT2_OS_LITES           4
 415
 416 /*
 417  * Revision levels
 418  */
 419 #define EXT2_GOOD_OLD_REV       0       /* The good old (original) format */
 420 #define EXT2_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
 421
 422 #define EXT2_CURRENT_REV        EXT2_GOOD_OLD_REV
 423 #define EXT2_MAX_SUPP_REV       EXT2_DYNAMIC_REV
 424
 425 #define EXT2_GOOD_OLD_INODE_SIZE 128
 426
 427 /*
 428  * Feature set definitions
 429  */
 430
 431 #define EXT2_HAS_COMPAT_FEATURE(sb,mask)                        \
 432         ( EXT2_SB(sb)->s_feature_compat & (mask) )
 433 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
 434         ( EXT2_SB(sb)->s_feature_ro_compat & (mask) )
 435 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask)                      \
 436         ( EXT2_SB(sb)->s_feature_incompat & (mask) )
 437
 438 #define EXT2_FEATURE_COMPAT_DIR_PREALLOC        0x0001
 439
 440 #define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
 441 #define EXT2_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
 442 #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
 443
 444 #define EXT2_FEATURE_INCOMPAT_COMPRESSION       0x0001
 445 #define EXT2_FEATURE_INCOMPAT_FILETYPE          0x0002
 446
 447 #define EXT2_FEATURE_COMPAT_SUPP        0
 448 #define EXT2_FEATURE_INCOMPAT_SUPP      EXT2_FEATURE_INCOMPAT_FILETYPE
 449 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
 450                                          EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
 451                                          EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
 452
 453 /*
 454  * Default values for user and/or group using reserved blocks
 455  */
 456 #define EXT2_DEF_RESUID         0
 457 #define EXT2_DEF_RESGID         0
 458
 459 /*
 460  * Structure of a directory entry
 461  */
 462 #define EXT2_NAME_LEN 255
 463
 464 struct ext2_dir_entry {
 465         __u32   inode;                  /* Inode number */
 466         __u16   rec_len;                /* Directory entry length */
 467         __u16   name_len;               /* Name length */
 468         char    name[EXT2_NAME_LEN];    /* File name */
 469 };
 470
 471 /*
 472  * The new version of the directory entry.  Since EXT2 structures are
 473  * stored in intel byte order, and the name_len field could never be
 474  * bigger than 255 chars, it's safe to reclaim the extra byte for the
 475  * file_type field.
 476  */
 477 struct ext2_dir_entry_2 {
 478         __u32   inode;                  /* Inode number */
 479         __u16   rec_len;                /* Directory entry length */
 480         __u8    name_len;               /* Name length */
 481         __u8    file_type;
 482         char    name[EXT2_NAME_LEN];    /* File name */
 483 };
 484
 485 /*
 486  * Ext2 directory file types.  Only the low 3 bits are used.  The
 487  * other bits are reserved for now.
 488  */
 489 #define EXT2_FT_UNKNOWN         0
 490 #define EXT2_FT_REG_FILE        1
 491 #define EXT2_FT_DIR             2
 492 #define EXT2_FT_CHRDEV          3
 493 #define EXT2_FT_BLKDEV          4
 494 #define EXT2_FT_FIFO            5
 495 #define EXT2_FT_SOCK            6
 496 #define EXT2_FT_SYMLINK         7
 497
 498 #define EXT2_FT_MAX             8
 499
 500 /*
 501  * EXT2_DIR_PAD defines the directory entries boundaries
 502  *
 503  * NOTE: It must be a multiple of 4
 504  */
 505 #define EXT2_DIR_PAD                    4
 506 #define EXT2_DIR_ROUND                  (EXT2_DIR_PAD - 1)
 507 #define EXT2_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT2_DIR_ROUND) & \
 508                                          ~EXT2_DIR_ROUND)
 509
 510 #ifdef __KERNEL__
 511 /*
 512  * Function prototypes
 513  */
 514
 515 /*
 516  * Ok, these declarations are also in <linux/kernel.h> but none of the
 517  * ext2 source programs needs to include it so they are duplicated here.
 518  */
 519 # define NORET_TYPE    /**/
 520 # define ATTRIB_NORET  __attribute__((noreturn))
 521 # define NORET_AND     noreturn,
 522
 523 /* acl.c */
 524 extern int ext2_permission (struct inode *, int);
 525
 526 /* balloc.c */
 527 extern int ext2_group_sparse(int group);
 528 extern int ext2_new_block (const struct inode *, unsigned long,
 529                            __u32 *, __u32 *, int *);
 530 extern void ext2_free_blocks (const struct inode *, unsigned long,
 531                               unsigned long);
 532 extern unsigned long ext2_count_free_blocks (struct super_block *);
 533 extern void ext2_check_blocks_bitmap (struct super_block *);
 534 extern struct ext2_group_desc * ext2_get_group_desc(struct super_block * sb,
 535                                                     unsigned int block_group,
 536                                                     struct buffer_head ** bh);
 537
 538 /* bitmap.c */
 539 extern unsigned long ext2_count_free (struct buffer_head *, unsigned);
 540
 541 /* dir.c */
 542 extern int ext2_check_dir_entry (const char *, struct inode *,
 543                                  struct ext2_dir_entry_2 *, struct buffer_head *,
 544                                  unsigned long);
 545
 546 /* file.c */
 547 extern int ext2_read (struct inode *, struct file *, char *, int);
 548 extern int ext2_write (struct inode *, struct file *, char *, int);
 549
 550 /* fsync.c */
 551 extern int ext2_sync_file (struct file *, struct dentry *, int);
 552 extern int ext2_fsync_inode (struct inode *, int);
 553
 554 /* ialloc.c */
 555 extern struct inode * ext2_new_inode (const struct inode *, int);
 556 extern void ext2_free_inode (struct inode *);
 557 extern unsigned long ext2_count_free_inodes (struct super_block *);
 558 extern void ext2_check_inodes_bitmap (struct super_block *);
 559
 560 /* inode.c */
 561
 562 extern struct buffer_head * ext2_getblk (struct inode *, long, int, int *);
 563 extern struct buffer_head * ext2_bread (struct inode *, int, int, int *);
 564
 565 extern void ext2_read_inode (struct inode *);
 566 extern void ext2_write_inode (struct inode *, int);
 567 extern void ext2_put_inode (struct inode *);
 568 extern void ext2_delete_inode (struct inode *);
 569 extern int ext2_sync_inode (struct inode *);
 570 extern void ext2_discard_prealloc (struct inode *);
 571
 572 /* ioctl.c */
 573 extern int ext2_ioctl (struct inode *, struct file *, unsigned int,
 574                        unsigned long);
 575
 576 /* namei.c */
 577 extern struct inode_operations ext2_dir_inode_operations;
 578
 579 /* super.c */
 580 extern void ext2_error (struct super_block *, const char *, const char *, ...)
 581         __attribute__ ((format (printf, 3, 4)));
 582 extern NORET_TYPE void ext2_panic (struct super_block *, const char *,
 583                                    const char *, ...)
 584         __attribute__ ((NORET_AND format (printf, 3, 4)));
 585 extern void ext2_warning (struct super_block *, const char *, const char *, ...)
 586         __attribute__ ((format (printf, 3, 4)));
 587 extern void ext2_put_super (struct super_block *);
 588 extern void ext2_write_super (struct super_block *);
 589 extern int ext2_remount (struct super_block *, int *, char *);
 590 extern struct super_block * ext2_read_super (struct super_block *,void *,int);
 591 extern int ext2_statfs (struct super_block *, struct statfs *);
 592
 593 /* truncate.c */
 594 extern void ext2_truncate (struct inode *);
 595
 596 /*
 597  * Inodes and files operations
 598  */
 599
 600 /* dir.c */
 601 extern struct file_operations ext2_dir_operations;
 602
 603 /* file.c */
 604 extern struct inode_operations ext2_file_inode_operations;
 605 extern struct file_operations ext2_file_operations;
 606
 607 /* symlink.c */
 608 extern struct inode_operations ext2_fast_symlink_inode_operations;
 609
 610 extern struct address_space_operations ext2_aops;
 611
 612 #endif  /* __KERNEL__ */
 613
 614 #endif  /* _LINUX_EXT2_FS_H */