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
  35 /*
  36  * The second extended file system version
  37  */
  38 #define EXT2FS_DATE             "95/08/09"
  39 #define EXT2FS_VERSION          "0.5b"
  40
  41 /*
  42  * Debug code
  43  */
  44 #ifdef EXT2FS_DEBUG
  45 #       define ext2_debug(f, a...)      { \
  46                                         printk ("EXT2-fs DEBUG (%s, %d): %s:", \
  47                                                 __FILE__, __LINE__, __FUNCTION__); \
  48                                         printk (f, ## a); \
  49                                         }
  50 #else
  51 #       define ext2_debug(f, a...)      /**/
  52 #endif
  53
  54 /*
  55  * Special inodes numbers
  56  */
  57 #define EXT2_BAD_INO             1      /* Bad blocks inode */
  58 #define EXT2_ROOT_INO            2      /* Root inode */
  59 #define EXT2_ACL_IDX_INO         3      /* ACL inode */
  60 #define EXT2_ACL_DATA_INO        4      /* ACL inode */
  61 #define EXT2_BOOT_LOADER_INO     5      /* Boot loader inode */
  62 #define EXT2_UNDEL_DIR_INO       6      /* Undelete directory inode */
  63
  64 /* First non-reserved inode for old ext2 filesystems */
  65 #define EXT2_GOOD_OLD_FIRST_INO 11
  66
  67 /*
  68  * The second extended file system magic number
  69  */
  70 #define EXT2_SUPER_MAGIC        0xEF53
  71
  72 /*
  73  * Maximal count of links to a file
  74  */
  75 #define EXT2_LINK_MAX           32000
  76
  77 /*
  78  * Macro-instructions used to manage several block sizes
  79  */
  80 #define EXT2_MIN_BLOCK_SIZE             1024
  81 #define EXT2_MAX_BLOCK_SIZE             4096
  82 #define EXT2_MIN_BLOCK_LOG_SIZE           10
  83 #ifdef __KERNEL__
  84 # define EXT2_BLOCK_SIZE(s)             ((s)->s_blocksize)
  85 #else
  86 # define EXT2_BLOCK_SIZE(s)             (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
  87 #endif
  88 #define EXT2_ACLE_PER_BLOCK(s)          (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_acl_entry))
  89 #define EXT2_ADDR_PER_BLOCK(s)          (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
  90 #ifdef __KERNEL__
  91 # define EXT2_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
  92 #else
  93 # define EXT2_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
  94 #endif
  95 #ifdef __KERNEL__
  96 #define EXT2_ADDR_PER_BLOCK_BITS(s)     ((s)->u.ext2_sb.s_addr_per_block_bits)
  97 #define EXT2_INODE_SIZE(s)              ((s)->u.ext2_sb.s_inode_size)
  98 #define EXT2_FIRST_INO(s)               ((s)->u.ext2_sb.s_first_ino)
  99 #else
 100 #define EXT2_INODE_SIZE(s)      (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
 101                                  EXT2_GOOD_OLD_INODE_SIZE : \
 102                                  (s)->s_inode_size)
 103 #define EXT2_FIRST_INO(s)       (((s)->s_rev_level == EXT2_GOOD_OLD_REV) ? \
 104                                  EXT2_GOOD_OLD_FIRST_INO : \
 105                                  (s)->s_first_ino)
 106 #endif
 107
 108 /*
 109  * Macro-instructions used to manage fragments
 110  */
 111 #define EXT2_MIN_FRAG_SIZE              1024
 112 #define EXT2_MAX_FRAG_SIZE              4096
 113 #define EXT2_MIN_FRAG_LOG_SIZE            10
 114 #ifdef __KERNEL__
 115 # define EXT2_FRAG_SIZE(s)              ((s)->u.ext2_sb.s_frag_size)
 116 # define EXT2_FRAGS_PER_BLOCK(s)        ((s)->u.ext2_sb.s_frags_per_block)
 117 #else
 118 # define EXT2_FRAG_SIZE(s)              (EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
 119 # define EXT2_FRAGS_PER_BLOCK(s)        (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
 120 #endif
 121
 122 /*
 123  * ACL structures
 124  */
 125 struct ext2_acl_header  /* Header of Access Control Lists */
 126 {
 127         __u32   aclh_size;
 128         __u32   aclh_file_count;
 129         __u32   aclh_acle_count;
 130         __u32   aclh_first_acle;
 131 };
 132
 133 struct ext2_acl_entry   /* Access Control List Entry */
 134 {
 135         __u32   acle_size;
 136         __u16   acle_perms;     /* Access permissions */
 137         __u16   acle_type;      /* Type of entry */
 138         __u16   acle_tag;       /* User or group identity */
 139         __u16   acle_pad1;
 140         __u32   acle_next;      /* Pointer on next entry for the */
 141                                         /* same inode or on next free entry */
 142 };
 143
 144 /*
 145  * Structure of a blocks group descriptor
 146  */
 147 struct ext2_group_desc
 148 {
 149         __u32   bg_block_bitmap;                /* Blocks bitmap block */
 150         __u32   bg_inode_bitmap;                /* Inodes bitmap block */
 151         __u32   bg_inode_table;         /* Inodes table block */
 152         __u16   bg_free_blocks_count;   /* Free blocks count */
 153         __u16   bg_free_inodes_count;   /* Free inodes count */
 154         __u16   bg_used_dirs_count;     /* Directories count */
 155         __u16   bg_pad;
 156         __u32   bg_reserved[3];
 157 };
 158
 159 /*
 160  * Macro-instructions used to manage group descriptors
 161  */
 162 #ifdef __KERNEL__
 163 # define EXT2_BLOCKS_PER_GROUP(s)       ((s)->u.ext2_sb.s_blocks_per_group)
 164 # define EXT2_DESC_PER_BLOCK(s)         ((s)->u.ext2_sb.s_desc_per_block)
 165 # define EXT2_INODES_PER_GROUP(s)       ((s)->u.ext2_sb.s_inodes_per_group)
 166 # define EXT2_DESC_PER_BLOCK_BITS(s)    ((s)->u.ext2_sb.s_desc_per_block_bits)
 167 #else
 168 # define EXT2_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 169 # define EXT2_DESC_PER_BLOCK(s)         (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
 170 # define EXT2_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 171 #endif
 172
 173 /*
 174  * Constants relative to the data blocks
 175  */
 176 #define EXT2_NDIR_BLOCKS                12
 177 #define EXT2_IND_BLOCK                  EXT2_NDIR_BLOCKS
 178 #define EXT2_DIND_BLOCK                 (EXT2_IND_BLOCK + 1)
 179 #define EXT2_TIND_BLOCK                 (EXT2_DIND_BLOCK + 1)
 180 #define EXT2_N_BLOCKS                   (EXT2_TIND_BLOCK + 1)
 181
 182 /*
 183  * Inode flags
 184  */
 185 #define EXT2_SECRM_FL                   0x00000001 /* Secure deletion */
 186 #define EXT2_UNRM_FL                    0x00000002 /* Undelete */
 187 #define EXT2_COMPR_FL                   0x00000004 /* Compress file */
 188 #define EXT2_SYNC_FL                    0x00000008 /* Synchronous updates */
 189 #define EXT2_IMMUTABLE_FL               0x00000010 /* Immutable file */
 190 #define EXT2_APPEND_FL                  0x00000020 /* writes to file may only append */
 191 #define EXT2_NODUMP_FL                  0x00000040 /* do not dump file */
 192 #define EXT2_NOATIME_FL                 0x00000080 /* do not update atime */
 193 #define EXT2_RESERVED_FL                0x80000000 /* reserved for ext2 lib */
 194
 195 /*
 196  * ioctl commands
 197  */
 198 #define EXT2_IOC_GETFLAGS               _IOR('f', 1, long)
 199 #define EXT2_IOC_SETFLAGS               _IOW('f', 2, long)
 200 #define EXT2_IOC_GETVERSION             _IOR('v', 1, long)
 201 #define EXT2_IOC_SETVERSION             _IOW('v', 2, long)
 202
 203 /*
 204  * Structure of an inode on the disk
 205  */
 206 struct ext2_inode {
 207         __u16   i_mode;         /* File mode */
 208         __u16   i_uid;          /* Owner Uid */
 209         __u32   i_size;         /* Size in bytes */
 210         __u32   i_atime;        /* Access time */
 211         __u32   i_ctime;        /* Creation time */
 212         __u32   i_mtime;        /* Modification time */
 213         __u32   i_dtime;        /* Deletion Time */
 214         __u16   i_gid;          /* Group Id */
 215         __u16   i_links_count;  /* Links count */
 216         __u32   i_blocks;       /* Blocks count */
 217         __u32   i_flags;        /* File flags */
 218         union {
 219                 struct {
 220                         __u32  l_i_reserved1;
 221                 } linux1;
 222                 struct {
 223                         __u32  h_i_translator;
 224                 } hurd1;
 225                 struct {
 226                         __u32  m_i_reserved1;
 227                 } masix1;
 228         } osd1;                         /* OS dependent 1 */
 229         __u32   i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
 230         __u32   i_version;      /* File version (for NFS) */
 231         __u32   i_file_acl;     /* File ACL */
 232         __u32   i_dir_acl;      /* Directory ACL */
 233         __u32   i_faddr;        /* Fragment address */
 234         union {
 235                 struct {
 236                         __u8    l_i_frag;       /* Fragment number */
 237                         __u8    l_i_fsize;      /* Fragment size */
 238                         __u16   i_pad1;
 239                         __u32   l_i_reserved2[2];
 240                 } linux2;
 241                 struct {
 242                         __u8    h_i_frag;       /* Fragment number */
 243                         __u8    h_i_fsize;      /* Fragment size */
 244                         __u16   h_i_mode_high;
 245                         __u16   h_i_uid_high;
 246                         __u16   h_i_gid_high;
 247                         __u32   h_i_author;
 248                 } hurd2;
 249                 struct {
 250                         __u8    m_i_frag;       /* Fragment number */
 251                         __u8    m_i_fsize;      /* Fragment size */
 252                         __u16   m_pad1;
 253                         __u32   m_i_reserved2[2];
 254                 } masix2;
 255         } osd2;                         /* OS dependent 2 */
 256 };
 257
 258 #if defined(__KERNEL__) || defined(__linux__)
 259 #define i_reserved1     osd1.linux1.l_i_reserved1
 260 #define i_frag          osd2.linux2.l_i_frag
 261 #define i_fsize         osd2.linux2.l_i_fsize
 262 #define i_reserved2     osd2.linux2.l_i_reserved2
 263 #endif
 264
 265 #ifdef  __hurd__
 266 #define i_translator    osd1.hurd1.h_i_translator
 267 #define i_frag          osd2.hurd2.h_i_frag;
 268 #define i_fsize         osd2.hurd2.h_i_fsize;
 269 #define i_uid_high      osd2.hurd2.h_i_uid_high
 270 #define i_gid_high      osd2.hurd2.h_i_gid_high
 271 #define i_author        osd2.hurd2.h_i_author
 272 #endif
 273
 274 #ifdef  __masix__
 275 #define i_reserved1     osd1.masix1.m_i_reserved1
 276 #define i_frag          osd2.masix2.m_i_frag
 277 #define i_fsize         osd2.masix2.m_i_fsize
 278 #define i_reserved2     osd2.masix2.m_i_reserved2
 279 #endif
 280
 281 /*
 282  * File system states
 283  */
 284 #define EXT2_VALID_FS                   0x0001  /* Unmounted cleanly */
 285 #define EXT2_ERROR_FS                   0x0002  /* Errors detected */
 286
 287 /*
 288  * Mount flags
 289  */
 290 #define EXT2_MOUNT_CHECK_NORMAL         0x0001  /* Do some more checks */
 291 #define EXT2_MOUNT_CHECK_STRICT         0x0002  /* Do again more checks */
 292 #define EXT2_MOUNT_CHECK                (EXT2_MOUNT_CHECK_NORMAL | \
 293                                          EXT2_MOUNT_CHECK_STRICT)
 294 #define EXT2_MOUNT_GRPID                0x0004  /* Create files with directory's group */
 295 #define EXT2_MOUNT_DEBUG                0x0008  /* Some debugging messages */
 296 #define EXT2_MOUNT_ERRORS_CONT          0x0010  /* Continue on errors */
 297 #define EXT2_MOUNT_ERRORS_RO            0x0020  /* Remount fs ro on errors */
 298 #define EXT2_MOUNT_ERRORS_PANIC         0x0040  /* Panic on errors */
 299 #define EXT2_MOUNT_MINIX_DF             0x0080  /* Mimics the Minix statfs */
 300
 301 #define clear_opt(o, opt)               o &= ~EXT2_MOUNT_##opt
 302 #define set_opt(o, opt)                 o |= EXT2_MOUNT_##opt
 303 #define test_opt(sb, opt)               ((sb)->u.ext2_sb.s_mount_opt & \
 304                                          EXT2_MOUNT_##opt)
 305 /*
 306  * Maximal mount counts between two filesystem checks
 307  */
 308 #define EXT2_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
 309 #define EXT2_DFL_CHECKINTERVAL          0       /* Don't use interval check */
 310
 311 /*
 312  * Behaviour when detecting errors
 313  */
 314 #define EXT2_ERRORS_CONTINUE            1       /* Continue execution */
 315 #define EXT2_ERRORS_RO                  2       /* Remount fs read-only */
 316 #define EXT2_ERRORS_PANIC               3       /* Panic */
 317 #define EXT2_ERRORS_DEFAULT             EXT2_ERRORS_CONTINUE
 318
 319 /*
 320  * Structure of the super block
 321  */
 322 struct ext2_super_block {
 323         __u32   s_inodes_count;         /* Inodes count */
 324         __u32   s_blocks_count;         /* Blocks count */
 325         __u32   s_r_blocks_count;       /* Reserved blocks count */
 326         __u32   s_free_blocks_count;    /* Free blocks count */
 327         __u32   s_free_inodes_count;    /* Free inodes count */
 328         __u32   s_first_data_block;     /* First Data Block */
 329         __u32   s_log_block_size;       /* Block size */
 330         __s32   s_log_frag_size;        /* Fragment size */
 331         __u32   s_blocks_per_group;     /* # Blocks per group */
 332         __u32   s_frags_per_group;      /* # Fragments per group */
 333         __u32   s_inodes_per_group;     /* # Inodes per group */
 334         __u32   s_mtime;                /* Mount time */
 335         __u32   s_wtime;                /* Write time */
 336         __u16   s_mnt_count;            /* Mount count */
 337         __s16   s_max_mnt_count;        /* Maximal mount count */
 338         __u16   s_magic;                /* Magic signature */
 339         __u16   s_state;                /* File system state */
 340         __u16   s_errors;               /* Behaviour when detecting errors */
 341         __u16   s_minor_rev_level;      /* minor revision level */
 342         __u32   s_lastcheck;            /* time of last check */
 343         __u32   s_checkinterval;        /* max. time between checks */
 344         __u32   s_creator_os;           /* OS */
 345         __u32   s_rev_level;            /* Revision level */
 346         __u16   s_def_resuid;           /* Default uid for reserved blocks */
 347         __u16   s_def_resgid;           /* Default gid for reserved blocks */
 348         /*
 349          * These fields are for EXT2_DYNAMIC_REV superblocks only.
 350          *
 351          * Note: the difference between the compatible feature set and
 352          * the incompatible feature set is that if there is a bit set
 353          * in the incompatible feature set that the kernel doesn't
 354          * know about, it should refuse to mount the filesystem.
 355          *
 356          * e2fsck's requirements are more strict; if it doesn't know
 357          * about a feature in either the compatible or incompatible
 358          * feature set, it must abort and not try to meddle with
 359          * things it doesn't understand...
 360          */
 361         __u32   s_first_ino;            /* First non-reserved inode */
 362         __u16   s_inode_size;           /* size of inode structure */
 363         __u16   s_block_group_nr;       /* block group # of this superblock */
 364         __u32   s_feature_compat;       /* compatible feature set */
 365         __u32   s_feature_incompat;     /* incompatible feature set */
 366         __u32   s_feature_ro_compat;    /* readonly-compatible feature set */
 367         __u8    s_uuid[16];             /* 128-bit uuid for volume */
 368         char    s_volume_name[16];      /* volume name */
 369         char    s_last_mounted[64];     /* directory where last mounted */
 370         __u32   s_reserved[206];        /* Padding to the end of the block */
 371 };
 372
 373 /*
 374  * Codes for operating systems
 375  */
 376 #define EXT2_OS_LINUX           0
 377 #define EXT2_OS_HURD            1
 378 #define EXT2_OS_MASIX           2
 379 #define EXT2_OS_FREEBSD         3
 380 #define EXT2_OS_LITES           4
 381
 382 /*
 383  * Revision levels
 384  */
 385 #define EXT2_GOOD_OLD_REV       0       /* The good old (original) format */
 386 #define EXT2_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
 387
 388 #define EXT2_CURRENT_REV        EXT2_GOOD_OLD_REV
 389 #define EXT2_MAX_SUPP_REV       EXT2_DYNAMIC_REV
 390
 391 #define EXT2_GOOD_OLD_INODE_SIZE 128
 392
 393 /*
 394  * Feature set definitions
 395  */
 396
 397 #define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
 398
 399 #define EXT2_FEATURE_COMPAT_SUPP        0
 400 #define EXT2_FEATURE_INCOMPAT_SUPP      0
 401 #define EXT2_FEATURE_RO_COMPAT_SUPP     EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER
 402
 403 /*
 404  * Default values for user and/or group using reserved blocks
 405  */
 406 #define EXT2_DEF_RESUID         0
 407 #define EXT2_DEF_RESGID         0
 408
 409 /*
 410  * Structure of a directory entry
 411  */
 412 #define EXT2_NAME_LEN 255
 413
 414 struct ext2_dir_entry {
 415         __u32   inode;                  /* Inode number */
 416         __u16   rec_len;                /* Directory entry length */
 417         __u16   name_len;               /* Name length */
 418         char    name[EXT2_NAME_LEN];    /* File name */
 419 };
 420
 421 /*
 422  * EXT2_DIR_PAD defines the directory entries boundaries
 423  *
 424  * NOTE: It must be a multiple of 4
 425  */
 426 #define EXT2_DIR_PAD                    4
 427 #define EXT2_DIR_ROUND                  (EXT2_DIR_PAD - 1)
 428 #define EXT2_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT2_DIR_ROUND) & \
 429                                          ~EXT2_DIR_ROUND)
 430
 431 #ifdef __KERNEL__
 432 /*
 433  * Function prototypes
 434  */
 435
 436 /*
 437  * Ok, these declarations are also in <linux/kernel.h> but none of the
 438  * ext2 source programs needs to include it so they are duplicated here.
 439  */
 440 #if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5)
 441 # define NORET_TYPE    __volatile__
 442 # define ATTRIB_NORET  /**/
 443 # define NORET_AND     /**/
 444 #else
 445 # define NORET_TYPE    /**/
 446 # define ATTRIB_NORET  __attribute__((noreturn))
 447 # define NORET_AND     noreturn,
 448 #endif
 449
 450 /* acl.c */
 451 extern int ext2_permission (struct inode *, int);
 452
 453 /* balloc.c */
 454 extern int ext2_new_block (const struct inode *, unsigned long,
 455                            __u32 *, __u32 *, int *);
 456 extern void ext2_free_blocks (const struct inode *, unsigned long,
 457                               unsigned long);
 458 extern unsigned long ext2_count_free_blocks (struct super_block *);
 459 extern void ext2_check_blocks_bitmap (struct super_block *);
 460
 461 /* bitmap.c */
 462 extern unsigned long ext2_count_free (struct buffer_head *, unsigned);
 463
 464 /* dir.c */
 465 extern int ext2_check_dir_entry (const char *, struct inode *,
 466                                  struct ext2_dir_entry *, struct buffer_head *,
 467                                  unsigned long);
 468
 469 /* file.c */
 470 extern int ext2_read (struct inode *, struct file *, char *, int);
 471 extern int ext2_write (struct inode *, struct file *, char *, int);
 472
 473 /* fsync.c */
 474 extern int ext2_sync_file (struct inode *, struct file *);
 475
 476 /* ialloc.c */
 477 extern struct inode * ext2_new_inode (const struct inode *, int, int *);
 478 extern void ext2_free_inode (struct inode *);
 479 extern unsigned long ext2_count_free_inodes (struct super_block *);
 480 extern void ext2_check_inodes_bitmap (struct super_block *);
 481
 482 /* inode.c */
 483 extern int ext2_bmap (struct inode *, int);
 484
 485 extern struct buffer_head * ext2_getblk (struct inode *, long, int, int *);
 486 extern struct buffer_head * ext2_bread (struct inode *, int, int, int *);
 487
 488 extern int ext2_getcluster (struct inode * inode, long block);
 489 extern void ext2_read_inode (struct inode *);
 490 extern void ext2_write_inode (struct inode *);
 491 extern void ext2_put_inode (struct inode *);
 492 extern int ext2_sync_inode (struct inode *);
 493 extern void ext2_discard_prealloc (struct inode *);
 494
 495 /* ioctl.c */
 496 extern int ext2_ioctl (struct inode *, struct file *, unsigned int,
 497                        unsigned long);
 498
 499 /* namei.c */
 500 extern void ext2_release (struct inode *, struct file *);
 501 extern int ext2_lookup (struct inode *,const char *, int, struct inode **);
 502 extern int ext2_create (struct inode *,const char *, int, int,
 503                         struct inode **);
 504 extern int ext2_mkdir (struct inode *, const char *, int, int);
 505 extern int ext2_rmdir (struct inode *, const char *, int);
 506 extern int ext2_unlink (struct inode *, const char *, int);
 507 extern int ext2_symlink (struct inode *, const char *, int, const char *);
 508 extern int ext2_link (struct inode *, struct inode *, const char *, int);
 509 extern int ext2_mknod (struct inode *, const char *, int, int, int);
 510 extern int ext2_rename (struct inode *, const char *, int,
 511                         struct inode *, const char *, int, int);
 512
 513 /* super.c */
 514 extern void ext2_error (struct super_block *, const char *, const char *, ...)
 515         __attribute__ ((format (printf, 3, 4)));
 516 extern NORET_TYPE void ext2_panic (struct super_block *, const char *,
 517                                    const char *, ...)
 518         __attribute__ ((NORET_AND format (printf, 3, 4)));
 519 extern void ext2_warning (struct super_block *, const char *, const char *, ...)
 520         __attribute__ ((format (printf, 3, 4)));
 521 extern void ext2_put_super (struct super_block *);
 522 extern void ext2_write_super (struct super_block *);
 523 extern int ext2_remount (struct super_block *, int *, char *);
 524 extern struct super_block * ext2_read_super (struct super_block *,void *,int);
 525 extern int init_ext2_fs(void);
 526 extern void ext2_statfs (struct super_block *, struct statfs *, int);
 527
 528 /* truncate.c */
 529 extern void ext2_truncate (struct inode *);
 530
 531 /*
 532  * Inodes and files operations
 533  */
 534
 535 /* dir.c */
 536 extern struct inode_operations ext2_dir_inode_operations;
 537
 538 /* file.c */
 539 extern struct inode_operations ext2_file_inode_operations;
 540
 541 /* symlink.c */
 542 extern struct inode_operations ext2_symlink_inode_operations;
 543
 544 #endif  /* __KERNEL__ */
 545
 546 #endif  /* _LINUX_EXT2_FS_H */