root/include/linux/ext2_fs.h

/* */

INCLUDED FROM

   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 #define EXT2_FIRST_INO          11      /* First non reserved inode */
  64 
  65 /*
  66  * The second extended file system magic number
  67  */
  68 #define EXT2_SUPER_MAGIC        0xEF53
  69 
  70 /*
  71  * Maximal count of links to a file
  72  */
  73 #define EXT2_LINK_MAX           32000
  74 
  75 /*
  76  * Macro-instructions used to manage several block sizes
  77  */
  78 #define EXT2_MIN_BLOCK_SIZE             1024
  79 #define EXT2_MAX_BLOCK_SIZE             4096
  80 #define EXT2_MIN_BLOCK_LOG_SIZE           10
  81 #ifdef __KERNEL__
  82 # define EXT2_BLOCK_SIZE(s)             ((s)->s_blocksize)
  83 #else
  84 # define EXT2_BLOCK_SIZE(s)             (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
  85 #endif
  86 #define EXT2_ACLE_PER_BLOCK(s)          (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_acl_entry))
  87 #define EXT2_ADDR_PER_BLOCK(s)          (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
  88 #ifdef __KERNEL__
  89 # define EXT2_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
  90 #else
  91 # define EXT2_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
  92 #endif
  93 #define EXT2_INODES_PER_BLOCK(s)        (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_inode))
  94 #ifdef __KERNEL__
  95 #define EXT2_ADDR_PER_BLOCK_BITS(s)     ((s)->u.ext2_sb.s_addr_per_block_bits)
  96 #define EXT2_INODES_PER_BLOCK_BITS(s)   ((s)->u.ext2_sb.s_inodes_per_block_bits)
  97 #endif
  98 
  99 /*
 100  * Macro-instructions used to manage fragments
 101  */
 102 #define EXT2_MIN_FRAG_SIZE              1024
 103 #define EXT2_MAX_FRAG_SIZE              4096
 104 #define EXT2_MIN_FRAG_LOG_SIZE            10
 105 #ifdef __KERNEL__
 106 # define EXT2_FRAG_SIZE(s)              ((s)->u.ext2_sb.s_frag_size)
 107 # define EXT2_FRAGS_PER_BLOCK(s)        ((s)->u.ext2_sb.s_frags_per_block)
 108 #else
 109 # define EXT2_FRAG_SIZE(s)              (EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
 110 # define EXT2_FRAGS_PER_BLOCK(s)        (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
 111 #endif
 112 
 113 /*
 114  * ACL structures
 115  */
 116 struct ext2_acl_header  /* Header of Access Control Lists */
 117 {
 118         __u32   aclh_size;
 119         __u32   aclh_file_count;
 120         __u32   aclh_acle_count;
 121         __u32   aclh_first_acle;
 122 };
 123 
 124 struct ext2_acl_entry   /* Access Control List Entry */
 125 {
 126         __u32   acle_size;
 127         __u16   acle_perms;     /* Access permissions */
 128         __u16   acle_type;      /* Type of entry */
 129         __u16   acle_tag;       /* User or group identity */
 130         __u16   acle_pad1;
 131         __u32   acle_next;      /* Pointer on next entry for the */
 132                                         /* same inode or on next free entry */
 133 };
 134 
 135 /*
 136  * Structure of a blocks group descriptor
 137  */
 138 struct ext2_group_desc
 139 {
 140         __u32   bg_block_bitmap;                /* Blocks bitmap block */
 141         __u32   bg_inode_bitmap;                /* Inodes bitmap block */
 142         __u32   bg_inode_table;         /* Inodes table block */
 143         __u16   bg_free_blocks_count;   /* Free blocks count */
 144         __u16   bg_free_inodes_count;   /* Free inodes count */
 145         __u16   bg_used_dirs_count;     /* Directories count */
 146         __u16   bg_pad;
 147         __u32   bg_reserved[3];
 148 };
 149 
 150 /*
 151  * Macro-instructions used to manage group descriptors
 152  */
 153 #ifdef __KERNEL__
 154 # define EXT2_BLOCKS_PER_GROUP(s)       ((s)->u.ext2_sb.s_blocks_per_group)
 155 # define EXT2_DESC_PER_BLOCK(s)         ((s)->u.ext2_sb.s_desc_per_block)
 156 # define EXT2_INODES_PER_GROUP(s)       ((s)->u.ext2_sb.s_inodes_per_group)
 157 # define EXT2_DESC_PER_BLOCK_BITS(s)    ((s)->u.ext2_sb.s_desc_per_block_bits)
 158 #else
 159 # define EXT2_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 160 # define EXT2_DESC_PER_BLOCK(s)         (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
 161 # define EXT2_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 162 #endif
 163 
 164 /*
 165  * Constants relative to the data blocks
 166  */
 167 #define EXT2_NDIR_BLOCKS                12
 168 #define EXT2_IND_BLOCK                  EXT2_NDIR_BLOCKS
 169 #define EXT2_DIND_BLOCK                 (EXT2_IND_BLOCK + 1)
 170 #define EXT2_TIND_BLOCK                 (EXT2_DIND_BLOCK + 1)
 171 #define EXT2_N_BLOCKS                   (EXT2_TIND_BLOCK + 1)
 172 
 173 /*
 174  * Inode flags
 175  */
 176 #define EXT2_SECRM_FL                   0x00000001 /* Secure deletion */
 177 #define EXT2_UNRM_FL                    0x00000002 /* Undelete */
 178 #define EXT2_COMPR_FL                   0x00000004 /* Compress file */
 179 #define EXT2_SYNC_FL                    0x00000008 /* Synchronous updates */
 180 #define EXT2_IMMUTABLE_FL               0x00000010 /* Immutable file */
 181 #define EXT2_APPEND_FL                  0x00000020 /* writes to file may only append */
 182 #define EXT2_NODUMP_FL                  0x00000040 /* do not dump file */
 183 
 184 /*
 185  * ioctl commands
 186  */
 187 #define EXT2_IOC_GETFLAGS               _IOR('f', 1, long)
 188 #define EXT2_IOC_SETFLAGS               _IOW('f', 2, long)
 189 #define EXT2_IOC_GETVERSION             _IOR('v', 1, long)
 190 #define EXT2_IOC_SETVERSION             _IOW('v', 2, long)
 191 
 192 /*
 193  * Structure of an inode on the disk
 194  */
 195 struct ext2_inode {
 196         __u16   i_mode;         /* File mode */
 197         __u16   i_uid;          /* Owner Uid */
 198         __u32   i_size;         /* Size in bytes */
 199         __u32   i_atime;        /* Access time */
 200         __u32   i_ctime;        /* Creation time */
 201         __u32   i_mtime;        /* Modification time */
 202         __u32   i_dtime;        /* Deletion Time */
 203         __u16   i_gid;          /* Group Id */
 204         __u16   i_links_count;  /* Links count */
 205         __u32   i_blocks;       /* Blocks count */
 206         __u32   i_flags;        /* File flags */
 207         union {
 208                 struct {
 209                         __u32  l_i_reserved1;
 210                 } linux1;
 211                 struct {
 212                         __u32  h_i_translator;
 213                 } hurd1;
 214                 struct {
 215                         __u32  m_i_reserved1;
 216                 } masix1;
 217         } osd1;                         /* OS dependent 1 */
 218         __u32   i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
 219         __u32   i_version;      /* File version (for NFS) */
 220         __u32   i_file_acl;     /* File ACL */
 221         __u32   i_dir_acl;      /* Directory ACL */
 222         __u32   i_faddr;        /* Fragment address */
 223         union {
 224                 struct {
 225                         __u8    l_i_frag;       /* Fragment number */
 226                         __u8    l_i_fsize;      /* Fragment size */
 227                         __u16   i_pad1;
 228                         __u32   l_i_reserved2[2];
 229                 } linux2;
 230                 struct {
 231                         __u8    h_i_frag;       /* Fragment number */
 232                         __u8    h_i_fsize;      /* Fragment size */
 233                         __u16   h_i_mode_high;
 234                         __u16   h_i_uid_high;
 235                         __u16   h_i_gid_high;
 236                         __u32   h_i_author;
 237                 } hurd2;
 238                 struct {
 239                         __u8    m_i_frag;       /* Fragment number */
 240                         __u8    m_i_fsize;      /* Fragment size */
 241                         __u16   m_pad1;
 242                         __u32   m_i_reserved2[2];
 243                 } masix2;
 244         } osd2;                         /* OS dependent 2 */
 245 };
 246 
 247 #if defined(__KERNEL__) || defined(__linux__)
 248 #define i_reserved1     osd1.linux1.l_i_reserved1
 249 #define i_frag          osd2.linux2.l_i_frag
 250 #define i_fsize         osd2.linux2.l_i_fsize
 251 #define i_reserved2     osd2.linux2.l_i_reserved2
 252 #endif
 253 
 254 #ifdef  __hurd__
 255 #define i_translator    osd1.hurd1.h_i_translator
 256 #define i_frag          osd2.hurd2.h_i_frag;
 257 #define i_fsize         osd2.hurd2.h_i_fsize;
 258 #define i_uid_high      osd2.hurd2.h_i_uid_high
 259 #define i_gid_high      osd2.hurd2.h_i_gid_high
 260 #define i_author        osd2.hurd2.h_i_author
 261 #endif
 262 
 263 #ifdef  __masix__
 264 #define i_reserved1     osd1.masix1.m_i_reserved1
 265 #define i_frag          osd2.masix2.m_i_frag
 266 #define i_fsize         osd2.masix2.m_i_fsize
 267 #define i_reserved2     osd2.masix2.m_i_reserved2
 268 #endif
 269 
 270 /*
 271  * File system states
 272  */
 273 #define EXT2_VALID_FS                   0x0001  /* Unmounted cleanly */
 274 #define EXT2_ERROR_FS                   0x0002  /* Errors detected */
 275 
 276 /*
 277  * Mount flags
 278  */
 279 #define EXT2_MOUNT_CHECK_NORMAL         0x0001  /* Do some more checks */
 280 #define EXT2_MOUNT_CHECK_STRICT         0x0002  /* Do again more checks */
 281 #define EXT2_MOUNT_CHECK                (EXT2_MOUNT_CHECK_NORMAL | \
 282                                          EXT2_MOUNT_CHECK_STRICT)
 283 #define EXT2_MOUNT_GRPID                0x0004  /* Create files with directory's group */
 284 #define EXT2_MOUNT_DEBUG                0x0008  /* Some debugging messages */
 285 #define EXT2_MOUNT_ERRORS_CONT          0x0010  /* Continue on errors */
 286 #define EXT2_MOUNT_ERRORS_RO            0x0020  /* Remount fs ro on errors */
 287 #define EXT2_MOUNT_ERRORS_PANIC         0x0040  /* Panic on errors */
 288 #define EXT2_MOUNT_MINIX_DF             0x0080  /* Mimics the Minix statfs */
 289 
 290 #define clear_opt(o, opt)               o &= ~EXT2_MOUNT_##opt
 291 #define set_opt(o, opt)                 o |= EXT2_MOUNT_##opt
 292 #define test_opt(sb, opt)               ((sb)->u.ext2_sb.s_mount_opt & \
 293                                          EXT2_MOUNT_##opt)
 294 /*
 295  * Maximal mount counts between two filesystem checks
 296  */
 297 #define EXT2_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
 298 #define EXT2_DFL_CHECKINTERVAL          0       /* Don't use interval check */
 299 
 300 /*
 301  * Behaviour when detecting errors
 302  */
 303 #define EXT2_ERRORS_CONTINUE            1       /* Continue execution */
 304 #define EXT2_ERRORS_RO                  2       /* Remount fs read-only */
 305 #define EXT2_ERRORS_PANIC               3       /* Panic */
 306 #define EXT2_ERRORS_DEFAULT             EXT2_ERRORS_CONTINUE
 307 
 308 /*
 309  * Structure of the super block
 310  */
 311 struct ext2_super_block {
 312         __u32   s_inodes_count;         /* Inodes count */
 313         __u32   s_blocks_count;         /* Blocks count */
 314         __u32   s_r_blocks_count;       /* Reserved blocks count */
 315         __u32   s_free_blocks_count;    /* Free blocks count */
 316         __u32   s_free_inodes_count;    /* Free inodes count */
 317         __u32   s_first_data_block;     /* First Data Block */
 318         __u32   s_log_block_size;       /* Block size */
 319         __s32   s_log_frag_size;        /* Fragment size */
 320         __u32   s_blocks_per_group;     /* # Blocks per group */
 321         __u32   s_frags_per_group;      /* # Fragments per group */
 322         __u32   s_inodes_per_group;     /* # Inodes per group */
 323         __u32   s_mtime;                /* Mount time */
 324         __u32   s_wtime;                /* Write time */
 325         __u16   s_mnt_count;            /* Mount count */
 326         __s16   s_max_mnt_count;        /* Maximal mount count */
 327         __u16   s_magic;                /* Magic signature */
 328         __u16   s_state;                /* File system state */
 329         __u16   s_errors;               /* Behaviour when detecting errors */
 330         __u16   s_pad;
 331         __u32   s_lastcheck;            /* time of last check */
 332         __u32   s_checkinterval;        /* max. time between checks */
 333         __u32   s_creator_os;           /* OS */
 334         __u32   s_rev_level;            /* Revision level */
 335         __u16   s_def_resuid;           /* Default uid for reserved blocks */
 336         __u16   s_def_resgid;           /* Default gid for reserved blocks */
 337         __u32   s_reserved[235];        /* Padding to the end of the block */
 338 };
 339 
 340 /*
 341  * Codes for operating systems
 342  */
 343 #define EXT2_OS_LINUX           0
 344 #define EXT2_OS_HURD            1
 345 #define EXT2_OS_MASIX           2
 346 #define EXT2_OS_FREEBSD         3
 347 #define EXT2_OS_LITES           4
 348 
 349 /*
 350  * Revision levels
 351  */
 352 #define EXT2_GOOD_OLD_REV       0       /* The good old (original) format */
 353 
 354 #define EXT2_CURRENT_REV        EXT2_GOOD_OLD_REV
 355 
 356 /*
 357  * Default values for user and/or group using reserved blocks
 358  */
 359 #define EXT2_DEF_RESUID         0
 360 #define EXT2_DEF_RESGID         0
 361 
 362 /*
 363  * Structure of a directory entry
 364  */
 365 #define EXT2_NAME_LEN 255
 366 
 367 struct ext2_dir_entry {
 368         __u32   inode;                  /* Inode number */
 369         __u16   rec_len;                /* Directory entry length */
 370         __u16   name_len;               /* Name length */
 371         char    name[EXT2_NAME_LEN];    /* File name */
 372 };
 373 
 374 /*
 375  * EXT2_DIR_PAD defines the directory entries boundaries
 376  *
 377  * NOTE: It must be a multiple of 4
 378  */
 379 #define EXT2_DIR_PAD                    4
 380 #define EXT2_DIR_ROUND                  (EXT2_DIR_PAD - 1)
 381 #define EXT2_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT2_DIR_ROUND) & \
 382                                          ~EXT2_DIR_ROUND)
 383 
 384 #ifdef __KERNEL__
 385 /*
 386  * Function prototypes
 387  */
 388 
 389 /*
 390  * Ok, these declarations are also in <linux/kernel.h> but none of the
 391  * ext2 source programs needs to include it so they are duplicated here.
 392  */
 393 #if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5)
 394 # define NORET_TYPE    __volatile__
 395 # define ATTRIB_NORET  /**/
 396 # define NORET_AND     /**/
 397 #else
 398 # define NORET_TYPE    /**/
 399 # define ATTRIB_NORET  __attribute__((noreturn))
 400 # define NORET_AND     noreturn,
 401 #endif
 402 
 403 /* acl.c */
 404 extern int ext2_permission (struct inode *, int);
 405 
 406 /* balloc.c */
 407 extern int ext2_new_block (const struct inode *, unsigned long,
 408                            __u32 *, __u32 *, int *);
 409 extern void ext2_free_blocks (const struct inode *, unsigned long,
 410                               unsigned long);
 411 extern unsigned long ext2_count_free_blocks (struct super_block *);
 412 extern void ext2_check_blocks_bitmap (struct super_block *);
 413 
 414 /* bitmap.c */
 415 extern unsigned long ext2_count_free (struct buffer_head *, unsigned);
 416 
 417 /* dir.c */
 418 extern int ext2_check_dir_entry (const char *, struct inode *,
 419                                  struct ext2_dir_entry *, struct buffer_head *,
 420                                  unsigned long);
 421 
 422 /* file.c */
 423 extern int ext2_read (struct inode *, struct file *, char *, int);
 424 extern int ext2_write (struct inode *, struct file *, char *, int);
 425 
 426 /* fsync.c */
 427 extern int ext2_sync_file (struct inode *, struct file *);
 428 
 429 /* ialloc.c */
 430 extern struct inode * ext2_new_inode (const struct inode *, int, int *);
 431 extern void ext2_free_inode (struct inode *);
 432 extern unsigned long ext2_count_free_inodes (struct super_block *);
 433 extern void ext2_check_inodes_bitmap (struct super_block *);
 434 
 435 /* inode.c */
 436 extern int ext2_bmap (struct inode *, int);
 437 
 438 extern struct buffer_head * ext2_getblk (struct inode *, long, int, int *);
 439 extern struct buffer_head * ext2_bread (struct inode *, int, int, int *);
 440 
 441 extern int ext2_getcluster (struct inode * inode, long block);
 442 extern void ext2_read_inode (struct inode *);
 443 extern void ext2_write_inode (struct inode *);
 444 extern void ext2_put_inode (struct inode *);
 445 extern int ext2_sync_inode (struct inode *);
 446 extern void ext2_discard_prealloc (struct inode *);
 447 
 448 /* ioctl.c */
 449 extern int ext2_ioctl (struct inode *, struct file *, unsigned int,
 450                        unsigned long);
 451 
 452 /* namei.c */
 453 extern void ext2_release (struct inode *, struct file *);
 454 extern int ext2_lookup (struct inode *,const char *, int, struct inode **);
 455 extern int ext2_create (struct inode *,const char *, int, int,
 456                         struct inode **);
 457 extern int ext2_mkdir (struct inode *, const char *, int, int);
 458 extern int ext2_rmdir (struct inode *, const char *, int);
 459 extern int ext2_unlink (struct inode *, const char *, int);
 460 extern int ext2_symlink (struct inode *, const char *, int, const char *);
 461 extern int ext2_link (struct inode *, struct inode *, const char *, int);
 462 extern int ext2_mknod (struct inode *, const char *, int, int, int);
 463 extern int ext2_rename (struct inode *, const char *, int,
 464                         struct inode *, const char *, int);
 465 
 466 /* super.c */
 467 extern void ext2_error (struct super_block *, const char *, const char *, ...)
 468         __attribute__ ((format (printf, 3, 4)));
 469 extern NORET_TYPE void ext2_panic (struct super_block *, const char *,
 470                                    const char *, ...)
 471         __attribute__ ((NORET_AND format (printf, 3, 4)));
 472 extern void ext2_warning (struct super_block *, const char *, const char *, ...)
 473         __attribute__ ((format (printf, 3, 4)));
 474 extern void ext2_put_super (struct super_block *);
 475 extern void ext2_write_super (struct super_block *);
 476 extern int ext2_remount (struct super_block *, int *, char *);
 477 extern struct super_block * ext2_read_super (struct super_block *,void *,int);
 478 extern int init_ext2_fs(void);
 479 extern void ext2_statfs (struct super_block *, struct statfs *, int);
 480 
 481 /* truncate.c */
 482 extern void ext2_truncate (struct inode *);
 483 
 484 /*
 485  * Inodes and files operations
 486  */
 487 
 488 /* dir.c */
 489 extern struct inode_operations ext2_dir_inode_operations;
 490 
 491 /* file.c */
 492 extern struct inode_operations ext2_file_inode_operations;
 493 
 494 /* symlink.c */
 495 extern struct inode_operations ext2_symlink_inode_operations;
 496 
 497 #endif  /* __KERNEL__ */
 498 
 499 #endif  /* _LINUX_EXT2_FS_H */

/* */