include/linux/fs.h

   1 #ifndef _LINUX_FS_H
   2 #define _LINUX_FS_H
   3
   4 /*
   5  * This file has definitions for some important file table
   6  * structures etc.
   7  */
   8
   9 #include <linux/config.h>
  10 #include <linux/linkage.h>
  11 #include <linux/limits.h>
  12 #include <linux/wait.h>
  13 #include <linux/types.h>
  14 #include <linux/vfs.h>
  15 #include <linux/net.h>
  16 #include <linux/kdev_t.h>
  17 #include <linux/ioctl.h>
  18 #include <linux/list.h>
  19 #include <linux/dcache.h>
  20 #include <linux/stat.h>
  21
  22 #include <asm/atomic.h>
  23 #include <asm/bitops.h>
  24 #include <asm/cache.h>
  25
  26 struct poll_table_struct;
  27
  28
  29 /*
  30  * It's silly to have NR_OPEN bigger than NR_FILE, but I'll fix
  31  * that later. Anyway, now the file code is no longer dependent
  32  * on bitmaps in unsigned longs, but uses the new fd_set structure..
  33  *
  34  * Some programs (notably those using select()) may have to be
  35  * recompiled to take full advantage of the new limits..
  36  */
  37
  38 /* Fixed constants first: */
  39 #undef NR_OPEN
  40 #define NR_OPEN 1024
  41
  42 #define BLOCK_SIZE_BITS 10
  43 #define BLOCK_SIZE (1<<BLOCK_SIZE_BITS)
  44
  45 /* And dynamically-tunable limits and defaults: */
  46 extern int max_inodes;
  47 extern int max_files, nr_files, nr_free_files;
  48 extern int max_super_blocks, nr_super_blocks;
  49
  50 #define NR_FILE  4096   /* this can well be larger on a larger system */
  51 #define NR_RESERVED_FILES 10 /* reserved for root */
  52 #define NR_SUPER 256
  53
  54 #define MAY_EXEC 1
  55 #define MAY_WRITE 2
  56 #define MAY_READ 4
  57
  58 #define FMODE_READ 1
  59 #define FMODE_WRITE 2
  60
  61 #define READ 0
  62 #define WRITE 1
  63 #define READA 2         /* read-ahead  - don't block if no resources */
  64 #define WRITEA 3        /* write-ahead - don't block if no resources */
  65
  66 #ifndef NULL
  67 #define NULL ((void *) 0)
  68 #endif
  69
  70 #define NIL_FILP        ((struct file *)0)
  71 #define SEL_IN          1
  72 #define SEL_OUT         2
  73 #define SEL_EX          4
  74
  75 /* public flags for file_system_type */
  76 #define FS_REQUIRES_DEV 1
  77 #define FS_NO_DCACHE    2 /* Only dcache the necessary things. */
  78 #define FS_NO_PRELIM    4 /* prevent preloading of dentries, even if
  79                            * FS_NO_DCACHE is not set.
  80                            */
  81 #define FS_IBASKET      8 /* FS does callback to free_ibasket() if space gets low. */
  82
  83 /*
  84  * These are the fs-independent mount-flags: up to 16 flags are supported
  85  */
  86 #define MS_RDONLY        1      /* Mount read-only */
  87 #define MS_NOSUID        2      /* Ignore suid and sgid bits */
  88 #define MS_NODEV         4      /* Disallow access to device special files */
  89 #define MS_NOEXEC        8      /* Disallow program execution */
  90 #define MS_SYNCHRONOUS  16      /* Writes are synced at once */
  91 #define MS_REMOUNT      32      /* Alter flags of a mounted FS */
  92 #define MS_MANDLOCK     64      /* Allow mandatory locks on an FS */
  93 #define S_QUOTA         128     /* Quota initialized for file/directory/symlink */
  94 #define S_APPEND        256     /* Append-only file */
  95 #define S_IMMUTABLE     512     /* Immutable file */
  96 #define MS_NOATIME      1024    /* Do not update access times. */
  97 #define MS_NODIRATIME   2048    /* Do not update directory access times */
  98
  99 /*
 100  * Flags that can be altered by MS_REMOUNT
 101  */
 102 #define MS_RMT_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS|MS_MANDLOCK|MS_NOATIME|MS_NODIRATIME)
 103
 104 /*
 105  * Magic mount flag number. Has to be or-ed to the flag values.
 106  */
 107 #define MS_MGC_VAL 0xC0ED0000   /* magic flag number to indicate "new" flags */
 108 #define MS_MGC_MSK 0xffff0000   /* magic flag number mask */
 109
 110 /*
 111  * Note that read-only etc flags are inode-specific: setting some file-system
 112  * flags just means all the inodes inherit those flags by default. It might be
 113  * possible to override it selectively if you really wanted to with some
 114  * ioctl() that is not currently implemented.
 115  *
 116  * Exception: MS_RDONLY is always applied to the entire file system.
 117  *
 118  * Unfortunately, it is possible to change a filesystems flags with it mounted
 119  * with files in use.  This means that all of the inodes will not have their
 120  * i_flags updated.  Hence, i_flags no longer inherit the superblock mount
 121  * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
 122  */
 123 #define __IS_FLG(inode,flg) (((inode)->i_sb && (inode)->i_sb->s_flags & (flg)) \
 124                                 || (inode)->i_flags & (flg))
 125
 126 #define IS_RDONLY(inode) (((inode)->i_sb) && ((inode)->i_sb->s_flags & MS_RDONLY))
 127 #define IS_NOSUID(inode)        __IS_FLG(inode, MS_NOSUID)
 128 #define IS_NODEV(inode)         __IS_FLG(inode, MS_NODEV)
 129 #define IS_NOEXEC(inode)        __IS_FLG(inode, MS_NOEXEC)
 130 #define IS_SYNC(inode)          __IS_FLG(inode, MS_SYNCHRONOUS)
 131 #define IS_MANDLOCK(inode)      __IS_FLG(inode, MS_MANDLOCK)
 132
 133 #define IS_QUOTAINIT(inode)     ((inode)->i_flags & S_QUOTA)
 134 #define IS_APPEND(inode)        ((inode)->i_flags & S_APPEND)
 135 #define IS_IMMUTABLE(inode)     ((inode)->i_flags & S_IMMUTABLE)
 136 #define IS_NOATIME(inode)       __IS_FLG(inode, MS_NOATIME)
 137 #define IS_NODIRATIME(inode)    __IS_FLG(inode, MS_NODIRATIME)
 138
 139 /* the read-only stuff doesn't really belong here, but any other place is
 140    probably as bad and I don't want to create yet another include file. */
 141
 142 #define BLKROSET   _IO(0x12,93) /* set device read-only (0 = read-write) */
 143 #define BLKROGET   _IO(0x12,94) /* get read-only status (0 = read_write) */
 144 #define BLKRRPART  _IO(0x12,95) /* re-read partition table */
 145 #define BLKGETSIZE _IO(0x12,96) /* return device size */
 146 #define BLKFLSBUF  _IO(0x12,97) /* flush buffer cache */
 147 #define BLKRASET   _IO(0x12,98) /* Set read ahead for block device */
 148 #define BLKRAGET   _IO(0x12,99) /* get current read ahead setting */
 149 #define BLKFRASET  _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
 150 #define BLKFRAGET  _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
 151 #define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
 152 #define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
 153
 154 #define BMAP_IOCTL 1            /* obsolete - kept for compatibility */
 155 #define FIBMAP     _IO(0x00,1)  /* bmap access */
 156 #define FIGETBSZ   _IO(0x00,2)  /* get the block size used for bmap */
 157
 158 #ifdef __KERNEL__
 159
 160 #include <asm/semaphore.h>
 161 #include <asm/byteorder.h>
 162 #include <asm/bitops.h>
 163
 164 extern void update_atime (struct inode *inode);
 165 #define UPDATE_ATIME(inode) update_atime (inode)
 166
 167 extern void buffer_init(void);
 168 extern void inode_init(void);
 169 extern void file_table_init(void);
 170 extern void dcache_init(void);
 171
 172 typedef char buffer_block[BLOCK_SIZE];
 173
 174 /* bh state bits */
 175 #define BH_Uptodate     0       /* 1 if the buffer contains valid data */
 176 #define BH_Dirty        1       /* 1 if the buffer is dirty */
 177 #define BH_Lock         2       /* 1 if the buffer is locked */
 178 #define BH_Req          3       /* 0 if the buffer has been invalidated */
 179 #define BH_Protected    6       /* 1 if the buffer is protected */
 180
 181 /*
 182  * Try to keep the most commonly used fields in single cache lines (16
 183  * bytes) to improve performance.  This ordering should be
 184  * particularly beneficial on 32-bit processors.
 185  *
 186  * We use the first 16 bytes for the data which is used in searches
 187  * over the block hash lists (ie. getblk(), find_buffer() and
 188  * friends).
 189  *
 190  * The second 16 bytes we use for lru buffer scans, as used by
 191  * sync_buffers() and refill_freelist().  -- sct
 192  */
 193 struct buffer_head {
 194         /* First cache line: */
 195         struct buffer_head * b_next;    /* Hash queue list */
 196         unsigned long b_blocknr;        /* block number */
 197         unsigned long b_size;           /* block size */
 198         kdev_t b_dev;                   /* device (B_FREE = free) */
 199         kdev_t b_rdev;                  /* Real device */
 200         unsigned long b_rsector;        /* Real buffer location on disk */
 201         struct buffer_head * b_this_page;       /* circular list of buffers in one page */
 202         unsigned long b_state;          /* buffer state bitmap (see above) */
 203         struct buffer_head * b_next_free;
 204         unsigned int b_count;           /* users using this block */
 205
 206         /* Non-performance-critical data follows. */
 207         char * b_data;                  /* pointer to data block (1024 bytes) */
 208         unsigned int b_list;            /* List that this buffer appears */
 209         unsigned long b_flushtime;      /* Time when this (dirty) buffer
 210                                          * should be written */
 211         struct wait_queue * b_wait;
 212         struct buffer_head ** b_pprev;          /* doubly linked list of hash-queue */
 213         struct buffer_head * b_prev_free;       /* doubly linked list of buffers */
 214         struct buffer_head * b_reqnext;         /* request queue */
 215
 216         /*
 217          * I/O completion
 218          */
 219         void (*b_end_io)(struct buffer_head *bh, int uptodate);
 220         void *b_dev_id;
 221 };
 222
 223 typedef void (bh_end_io_t)(struct buffer_head *bh, int uptodate);
 224 void init_buffer(struct buffer_head *bh, kdev_t dev, int block,
 225                  bh_end_io_t *handler, void *dev_id);
 226
 227 static inline int buffer_uptodate(struct buffer_head * bh)
 228 {
 229         return test_bit(BH_Uptodate, &bh->b_state);
 230 }
 231
 232 static inline int buffer_dirty(struct buffer_head * bh)
 233 {
 234         return test_bit(BH_Dirty, &bh->b_state);
 235 }
 236
 237 static inline int buffer_locked(struct buffer_head * bh)
 238 {
 239         return test_bit(BH_Lock, &bh->b_state);
 240 }
 241
 242 static inline int buffer_req(struct buffer_head * bh)
 243 {
 244         return test_bit(BH_Req, &bh->b_state);
 245 }
 246
 247 static inline int buffer_protected(struct buffer_head * bh)
 248 {
 249         return test_bit(BH_Protected, &bh->b_state);
 250 }
 251
 252 /*
 253  * Deprecated - we don't keep per-buffer reference flags
 254  * any more.
 255  *
 256  * We _could_ try to update the page reference, but that
 257  * doesn't seem to really be worth it either. If we did,
 258  * it would look something like this:
 259  *
 260  *      #define buffer_page(bh)         (mem_map + MAP_NR((bh)->b_data))
 261  *      #define touch_buffer(bh)        set_bit(PG_referenced, &buffer_page(bh)->flags)
 262  */
 263 #define touch_buffer(bh)        do { } while (0)
 264
 265 #include <linux/pipe_fs_i.h>
 266 #include <linux/minix_fs_i.h>
 267 #include <linux/ext2_fs_i.h>
 268 #include <linux/hpfs_fs_i.h>
 269 #include <linux/ntfs_fs_i.h>
 270 #include <linux/msdos_fs_i.h>
 271 #include <linux/umsdos_fs_i.h>
 272 #include <linux/iso_fs_i.h>
 273 #include <linux/nfs_fs_i.h>
 274 #include <linux/sysv_fs_i.h>
 275 #include <linux/affs_fs_i.h>
 276 #include <linux/ufs_fs_i.h>
 277 #include <linux/coda_fs_i.h>
 278 #include <linux/romfs_fs_i.h>
 279 #include <linux/smb_fs_i.h>
 280 #include <linux/hfs_fs_i.h>
 281 #include <linux/adfs_fs_i.h>
 282 #include <linux/qnx4_fs_i.h>
 283
 284 /*
 285  * Attribute flags.  These should be or-ed together to figure out what
 286  * has been changed!
 287  */
 288 #define ATTR_MODE       1
 289 #define ATTR_UID        2
 290 #define ATTR_GID        4
 291 #define ATTR_SIZE       8
 292 #define ATTR_ATIME      16
 293 #define ATTR_MTIME      32
 294 #define ATTR_CTIME      64
 295 #define ATTR_ATIME_SET  128
 296 #define ATTR_MTIME_SET  256
 297 #define ATTR_FORCE      512     /* Not a change, but a change it */
 298 #define ATTR_ATTR_FLAG  1024
 299
 300 /*
 301  * This is the Inode Attributes structure, used for notify_change().  It
 302  * uses the above definitions as flags, to know which values have changed.
 303  * Also, in this manner, a Filesystem can look at only the values it cares
 304  * about.  Basically, these are the attributes that the VFS layer can
 305  * request to change from the FS layer.
 306  *
 307  * Derek Atkins <warlord@MIT.EDU> 94-10-20
 308  */
 309 struct iattr {
 310         unsigned int    ia_valid;
 311         umode_t         ia_mode;
 312         uid_t           ia_uid;
 313         gid_t           ia_gid;
 314         off_t           ia_size;
 315         time_t          ia_atime;
 316         time_t          ia_mtime;
 317         time_t          ia_ctime;
 318         unsigned int    ia_attr_flags;
 319 };
 320
 321 /*
 322  * This is the inode attributes flag definitions
 323  */
 324 #define ATTR_FLAG_SYNCRONOUS    1       /* Syncronous write */
 325 #define ATTR_FLAG_NOATIME       2       /* Don't update atime */
 326 #define ATTR_FLAG_APPEND        4       /* Append-only file */
 327 #define ATTR_FLAG_IMMUTABLE     8       /* Immutable file */
 328 #define ATTR_FLAG_NODIRATIME    16      /* Don't update atime for directory */
 329
 330 /*
 331  * Includes for diskquotas and mount structures.
 332  */
 333 #include <linux/quota.h>
 334 #include <linux/mount.h>
 335
 336 struct inode {
 337         struct list_head        i_hash;
 338         struct list_head        i_list;
 339         struct list_head        i_dentry;
 340
 341         unsigned long           i_ino;
 342         unsigned int            i_count;
 343         kdev_t                  i_dev;
 344         umode_t                 i_mode;
 345         nlink_t                 i_nlink;
 346         uid_t                   i_uid;
 347         gid_t                   i_gid;
 348         kdev_t                  i_rdev;
 349         off_t                   i_size;
 350         time_t                  i_atime;
 351         time_t                  i_mtime;
 352         time_t                  i_ctime;
 353         unsigned long           i_blksize;
 354         unsigned long           i_blocks;
 355         unsigned long           i_version;
 356         unsigned long           i_nrpages;
 357         struct semaphore        i_sem;
 358         struct semaphore        i_atomic_write;
 359         struct inode_operations *i_op;
 360         struct super_block      *i_sb;
 361         struct wait_queue       *i_wait;
 362         struct file_lock        *i_flock;
 363         struct vm_area_struct   *i_mmap;
 364         struct page             *i_pages;
 365         struct dquot            *i_dquot[MAXQUOTAS];
 366
 367         unsigned long           i_state;
 368
 369         unsigned int            i_flags;
 370         unsigned char           i_pipe;
 371         unsigned char           i_sock;
 372
 373         int                     i_writecount;
 374         unsigned int            i_attr_flags;
 375         union {
 376                 struct pipe_inode_info          pipe_i;
 377                 struct minix_inode_info         minix_i;
 378                 struct ext2_inode_info          ext2_i;
 379                 struct hpfs_inode_info          hpfs_i;
 380                 struct ntfs_inode_info          ntfs_i;
 381                 struct msdos_inode_info         msdos_i;
 382                 struct umsdos_inode_info        umsdos_i;
 383                 struct iso_inode_info           isofs_i;
 384                 struct nfs_inode_info           nfs_i;
 385                 struct sysv_inode_info          sysv_i;
 386                 struct affs_inode_info          affs_i;
 387                 struct ufs_inode_info           ufs_i;
 388                 struct romfs_inode_info         romfs_i;
 389                 struct coda_inode_info          coda_i;
 390                 struct smb_inode_info           smbfs_i;
 391                 struct hfs_inode_info           hfs_i;
 392                 struct adfs_inode_info          adfs_i;
 393                 struct qnx4_inode_info          qnx4_i;
 394                 struct socket                   socket_i;
 395                 void                            *generic_ip;
 396         } u;
 397 };
 398
 399 /* Inode state bits.. */
 400 #define I_DIRTY         1
 401 #define I_LOCK          2
 402 #define I_FREEING       4
 403
 404 extern void __mark_inode_dirty(struct inode *);
 405 static inline void mark_inode_dirty(struct inode *inode)
 406 {
 407         if (!(inode->i_state & I_DIRTY))
 408                 __mark_inode_dirty(inode);
 409 }
 410
 411 struct fown_struct {
 412         int pid;                /* pid or -pgrp where SIGIO should be sent */
 413         uid_t uid, euid;        /* uid/euid of process setting the owner */
 414         int signum;             /* posix.1b rt signal to be delivered on IO */
 415 };
 416
 417 struct file {
 418         struct file             *f_next, **f_pprev;
 419         struct dentry           *f_dentry;
 420         struct file_operations  *f_op;
 421         mode_t                  f_mode;
 422         loff_t                  f_pos;
 423         unsigned int            f_count, f_flags;
 424         unsigned long           f_reada, f_ramax, f_raend, f_ralen, f_rawin;
 425         struct fown_struct      f_owner;
 426
 427         unsigned long           f_version;
 428
 429         /* needed for tty driver, and maybe others */
 430         void                    *private_data;
 431 };
 432
 433 extern int init_private_file(struct file *, struct dentry *, int);
 434
 435 #define FL_POSIX        1
 436 #define FL_FLOCK        2
 437 #define FL_BROKEN       4       /* broken flock() emulation */
 438 #define FL_ACCESS       8       /* for processes suspended by mandatory locking */
 439 #define FL_LOCKD        16      /* lock held by rpc.lockd */
 440
 441 /*
 442  * The POSIX file lock owner is determined by
 443  * the "struct files_struct" in the thread group
 444  * (or NULL for no owner - BSD locks).
 445  *
 446  * Lockd stuffs a "host" pointer into this.
 447  */
 448 typedef struct files_struct *fl_owner_t;
 449
 450 struct file_lock {
 451         struct file_lock *fl_next;      /* singly linked list for this inode  */
 452         struct file_lock *fl_nextlink;  /* doubly linked list of all locks */
 453         struct file_lock *fl_prevlink;  /* used to simplify lock removal */
 454         struct file_lock *fl_nextblock; /* circular list of blocked processes */
 455         struct file_lock *fl_prevblock;
 456         fl_owner_t fl_owner;
 457         unsigned int fl_pid;
 458         struct wait_queue *fl_wait;
 459         struct file *fl_file;
 460         unsigned char fl_flags;
 461         unsigned char fl_type;
 462         off_t fl_start;
 463         off_t fl_end;
 464
 465         void (*fl_notify)(struct file_lock *);  /* unblock callback */
 466
 467         union {
 468                 struct nfs_lock_info    nfs_fl;
 469         } fl_u;
 470 };
 471
 472 extern struct file_lock                 *file_lock_table;
 473
 474 #include <linux/fcntl.h>
 475
 476 extern int fcntl_getlk(unsigned int fd, struct flock *l);
 477 extern int fcntl_setlk(unsigned int fd, unsigned int cmd, struct flock *l);
 478
 479 /* fs/locks.c */
 480 extern void locks_remove_posix(struct file *, fl_owner_t id);
 481 extern void locks_remove_flock(struct file *);
 482 extern struct file_lock *posix_test_lock(struct file *, struct file_lock *);
 483 extern int posix_lock_file(struct file *, struct file_lock *, unsigned int);
 484 extern void posix_block_lock(struct file_lock *, struct file_lock *);
 485 extern void posix_unblock_lock(struct file_lock *);
 486
 487 #include <linux/stat.h>
 488
 489 struct fasync_struct {
 490         int    magic;
 491         int    fa_fd;
 492         struct fasync_struct    *fa_next; /* singly linked list */
 493         struct file             *fa_file;
 494 };
 495
 496 #define FASYNC_MAGIC 0x4601
 497
 498 extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
 499
 500 #include <linux/minix_fs_sb.h>
 501 #include <linux/ext2_fs_sb.h>
 502 #include <linux/hpfs_fs_sb.h>
 503 #include <linux/ntfs_fs_sb.h>
 504 #include <linux/msdos_fs_sb.h>
 505 #include <linux/iso_fs_sb.h>
 506 #include <linux/nfs_fs_sb.h>
 507 #include <linux/sysv_fs_sb.h>
 508 #include <linux/affs_fs_sb.h>
 509 #include <linux/ufs_fs_sb.h>
 510 #include <linux/romfs_fs_sb.h>
 511 #include <linux/smb_fs_sb.h>
 512 #include <linux/hfs_fs_sb.h>
 513 #include <linux/adfs_fs_sb.h>
 514 #include <linux/qnx4_fs_sb.h>
 515
 516 extern struct list_head super_blocks;
 517
 518 #define sb_entry(list)  list_entry((list), struct super_block, s_list)
 519 struct super_block {
 520         struct list_head        s_list;         /* Keep this first */
 521         kdev_t                  s_dev;
 522         unsigned long           s_blocksize;
 523         unsigned char           s_blocksize_bits;
 524         unsigned char           s_lock;
 525         unsigned char           s_rd_only;
 526         unsigned char           s_dirt;
 527         struct file_system_type *s_type;
 528         struct super_operations *s_op;
 529         struct dquot_operations *dq_op;
 530         unsigned long           s_flags;
 531         unsigned long           s_magic;
 532         unsigned long           s_time;
 533         struct dentry           *s_root;
 534         struct wait_queue       *s_wait;
 535
 536         struct inode            *s_ibasket;
 537         short int               s_ibasket_count;
 538         short int               s_ibasket_max;
 539         struct list_head        s_dirty;        /* dirty inodes */
 540
 541         union {
 542                 struct minix_sb_info    minix_sb;
 543                 struct ext2_sb_info     ext2_sb;
 544                 struct hpfs_sb_info     hpfs_sb;
 545                 struct ntfs_sb_info     ntfs_sb;
 546                 struct msdos_sb_info    msdos_sb;
 547                 struct isofs_sb_info    isofs_sb;
 548                 struct nfs_sb_info      nfs_sb;
 549                 struct sysv_sb_info     sysv_sb;
 550                 struct affs_sb_info     affs_sb;
 551                 struct ufs_sb_info      ufs_sb;
 552                 struct romfs_sb_info    romfs_sb;
 553                 struct smb_sb_info      smbfs_sb;
 554                 struct hfs_sb_info      hfs_sb;
 555                 struct adfs_sb_info     adfs_sb;
 556                 struct qnx4_sb_info     qnx4_sb;
 557                 void                    *generic_sbp;
 558         } u;
 559 };
 560
 561 /*
 562  * VFS helper functions..
 563  */
 564 extern int vfs_rmdir(struct inode *, struct dentry *);
 565 extern int vfs_unlink(struct inode *, struct dentry *);
 566 extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
 567
 568 /*
 569  * This is the "filldir" function type, used by readdir() to let
 570  * the kernel specify what kind of dirent layout it wants to have.
 571  * This allows the kernel to read directories into kernel space or
 572  * to have different dirent layouts depending on the binary type.
 573  */
 574 typedef int (*filldir_t)(void *, const char *, int, off_t, ino_t);
 575
 576 struct file_operations {
 577         loff_t (*llseek) (struct file *, loff_t, int);
 578         ssize_t (*read) (struct file *, char *, size_t, loff_t *);
 579         ssize_t (*write) (struct file *, const char *, size_t, loff_t *);
 580         int (*readdir) (struct file *, void *, filldir_t);
 581         unsigned int (*poll) (struct file *, struct poll_table_struct *);
 582         int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
 583         int (*mmap) (struct file *, struct vm_area_struct *);
 584         int (*open) (struct inode *, struct file *);
 585         int (*flush) (struct file *);
 586         int (*release) (struct inode *, struct file *);
 587         int (*fsync) (struct file *, struct dentry *);
 588         int (*fasync) (int, struct file *, int);
 589         int (*check_media_change) (kdev_t dev);
 590         int (*revalidate) (kdev_t dev);
 591         int (*lock) (struct file *, int, struct file_lock *);
 592 };
 593
 594 struct inode_operations {
 595         struct file_operations * default_file_ops;
 596         int (*create) (struct inode *,struct dentry *,int);
 597         int (*lookup) (struct inode *,struct dentry *);
 598         int (*link) (struct dentry *,struct inode *,struct dentry *);
 599         int (*unlink) (struct inode *,struct dentry *);
 600         int (*symlink) (struct inode *,struct dentry *,const char *);
 601         int (*mkdir) (struct inode *,struct dentry *,int);
 602         int (*rmdir) (struct inode *,struct dentry *);
 603         int (*mknod) (struct inode *,struct dentry *,int,int);
 604         int (*rename) (struct inode *, struct dentry *,
 605                         struct inode *, struct dentry *);
 606         int (*readlink) (struct dentry *, char *,int);
 607         struct dentry * (*follow_link) (struct dentry *, struct dentry *, unsigned int);
 608         int (*readpage) (struct file *, struct page *);
 609         int (*writepage) (struct file *, struct page *);
 610         int (*bmap) (struct inode *,int);
 611         void (*truncate) (struct inode *);
 612         int (*permission) (struct inode *, int);
 613         int (*smap) (struct inode *,int);
 614         int (*updatepage) (struct file *, struct page *, unsigned long, unsigned int, int);
 615         int (*revalidate) (struct dentry *);
 616 };
 617
 618 struct super_operations {
 619         void (*read_inode) (struct inode *);
 620         void (*write_inode) (struct inode *);
 621         void (*put_inode) (struct inode *);
 622         void (*delete_inode) (struct inode *);
 623         int (*notify_change) (struct dentry *, struct iattr *);
 624         void (*put_super) (struct super_block *);
 625         void (*write_super) (struct super_block *);
 626         int (*statfs) (struct super_block *, struct statfs *, int);
 627         int (*remount_fs) (struct super_block *, int *, char *);
 628         void (*clear_inode) (struct inode *);
 629         void (*umount_begin) (struct super_block *);
 630 };
 631
 632 struct dquot_operations {
 633         void (*initialize) (struct inode *, short);
 634         void (*drop) (struct inode *);
 635         int (*alloc_block) (const struct inode *, unsigned long, uid_t, char);
 636         int (*alloc_inode) (const struct inode *, unsigned long, uid_t);
 637         void (*free_block) (const struct inode *, unsigned long);
 638         void (*free_inode) (const struct inode *, unsigned long);
 639         int (*transfer) (struct inode *, struct iattr *, char, uid_t);
 640 };
 641
 642 struct file_system_type {
 643         const char *name;
 644         int fs_flags;
 645         struct super_block *(*read_super) (struct super_block *, void *, int);
 646         struct file_system_type * next;
 647 };
 648
 649 extern int register_filesystem(struct file_system_type *);
 650 extern int unregister_filesystem(struct file_system_type *);
 651
 652
 653 #define FLOCK_VERIFY_READ  1
 654 #define FLOCK_VERIFY_WRITE 2
 655
 656 extern int locks_mandatory_locked(struct inode *inode);
 657 extern int locks_mandatory_area(int read_write, struct inode *inode,
 658                                 struct file *filp, loff_t offset,
 659                                 size_t count);
 660
 661 extern inline int locks_verify_locked(struct inode *inode)
 662 {
 663         /* Candidates for mandatory locking have the setgid bit set
 664          * but no group execute bit -  an otherwise meaningless combination.
 665          */
 666         if (IS_MANDLOCK(inode) &&
 667             (inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
 668                 return (locks_mandatory_locked(inode));
 669         return (0);
 670 }
 671
 672 extern inline int locks_verify_area(int read_write, struct inode *inode,
 673                                     struct file *filp, loff_t offset,
 674                                     size_t count)
 675 {
 676         /* Candidates for mandatory locking have the setgid bit set
 677          * but no group execute bit -  an otherwise meaningless combination.
 678          */
 679         if (IS_MANDLOCK(inode) &&
 680             (inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
 681                 return (locks_mandatory_area(read_write, inode, filp, offset,
 682                                              count));
 683         return (0);
 684 }
 685
 686
 687 /* fs/open.c */
 688
 689 asmlinkage int sys_open(const char *, int, int);
 690 asmlinkage int sys_close(unsigned int);         /* yes, it's really unsigned */
 691 extern int do_truncate(struct dentry *, unsigned long);
 692 extern int get_unused_fd(void);
 693 extern void put_unused_fd(unsigned int);
 694 extern int close_fp(struct file *, fl_owner_t id);
 695 extern struct file *filp_open(const char *, int, int);
 696
 697 extern char * getname(const char * filename);
 698 #define __getname()     ((char *) __get_free_page(GFP_KERNEL))
 699 #define putname(name)   free_page((unsigned long)(name))
 700
 701 extern void kill_fasync(struct fasync_struct *fa, int sig);
 702 extern int register_blkdev(unsigned int, const char *, struct file_operations *);
 703 extern int unregister_blkdev(unsigned int major, const char * name);
 704 extern int blkdev_open(struct inode * inode, struct file * filp);
 705 extern int blkdev_release (struct inode * inode);
 706 extern struct file_operations def_blk_fops;
 707 extern struct inode_operations blkdev_inode_operations;
 708
 709 /* fs/devices.c */
 710 extern int register_chrdev(unsigned int, const char *, struct file_operations *);
 711 extern int unregister_chrdev(unsigned int major, const char * name);
 712 extern int chrdev_open(struct inode * inode, struct file * filp);
 713 extern struct file_operations def_chr_fops;
 714 extern struct inode_operations chrdev_inode_operations;
 715 extern char * bdevname(kdev_t dev);
 716 extern char * cdevname(kdev_t dev);
 717 extern char * kdevname(kdev_t dev);
 718
 719
 720 extern void init_fifo(struct inode * inode);
 721 extern struct inode_operations fifo_inode_operations;
 722
 723 /* Invalid inode operations -- fs/bad_inode.c */
 724 extern void make_bad_inode(struct inode * inode);
 725 extern int is_bad_inode(struct inode * inode);
 726
 727 extern struct file_operations connecting_fifo_fops;
 728 extern struct file_operations read_fifo_fops;
 729 extern struct file_operations write_fifo_fops;
 730 extern struct file_operations rdwr_fifo_fops;
 731 extern struct file_operations read_pipe_fops;
 732 extern struct file_operations write_pipe_fops;
 733 extern struct file_operations rdwr_pipe_fops;
 734
 735 extern struct file_system_type *get_fs_type(const char *name);
 736
 737 extern int fs_may_remount_ro(struct super_block *);
 738 extern int fs_may_mount(kdev_t dev);
 739
 740 extern struct file *inuse_filps;
 741
 742 extern void refile_buffer(struct buffer_head * buf);
 743 extern void set_writetime(struct buffer_head * buf, int flag);
 744 extern int try_to_free_buffers(struct page *);
 745
 746 extern int nr_buffers;
 747 extern int buffermem;
 748 extern int nr_buffer_heads;
 749
 750 #define BUF_CLEAN       0
 751 #define BUF_LOCKED      1       /* Buffers scheduled for write */
 752 #define BUF_DIRTY       2       /* Dirty buffers, not yet scheduled for write */
 753 #define NR_LIST         3
 754
 755 void mark_buffer_uptodate(struct buffer_head * bh, int on);
 756
 757 extern inline void mark_buffer_clean(struct buffer_head * bh)
 758 {
 759         if (test_and_clear_bit(BH_Dirty, &bh->b_state)) {
 760                 if (bh->b_list == BUF_DIRTY)
 761                         refile_buffer(bh);
 762         }
 763 }
 764
 765 extern inline void mark_buffer_dirty(struct buffer_head * bh, int flag)
 766 {
 767         if (!test_and_set_bit(BH_Dirty, &bh->b_state)) {
 768                 set_writetime(bh, flag);
 769                 if (bh->b_list != BUF_DIRTY)
 770                         refile_buffer(bh);
 771         }
 772 }
 773
 774 extern int check_disk_change(kdev_t dev);
 775 extern int invalidate_inodes(struct super_block * sb);
 776 extern void invalidate_inode_pages(struct inode *);
 777 extern void invalidate_buffers(kdev_t dev);
 778 extern int floppy_is_wp(int minor);
 779 extern void sync_inodes(kdev_t dev);
 780 extern void write_inode_now(struct inode *inode);
 781 extern void sync_dev(kdev_t dev);
 782 extern int fsync_dev(kdev_t dev);
 783 extern void sync_supers(kdev_t dev);
 784 extern int bmap(struct inode * inode,int block);
 785 extern int notify_change(struct dentry *, struct iattr *);
 786 extern int permission(struct inode * inode,int mask);
 787 extern int get_write_access(struct inode *inode);
 788 extern void put_write_access(struct inode *inode);
 789 extern struct dentry * open_namei(const char * pathname, int flag, int mode);
 790 extern struct dentry * do_mknod(const char * filename, int mode, dev_t dev);
 791 extern int do_pipe(int *);
 792
 793 /* fs/dcache.c -- generic fs support functions */
 794 extern int is_subdir(struct dentry *, struct dentry *);
 795 extern ino_t find_inode_number(struct dentry *, struct qstr *);
 796
 797 /*
 798  * Kernel pointers have redundant information, so we can use a
 799  * scheme where we can return either an error code or a dentry
 800  * pointer with the same return value.
 801  *
 802  * This should be a per-architecture thing, to allow different
 803  * error and pointer decisions.
 804  */
 805 #define ERR_PTR(err)    ((void *)((long)(err)))
 806 #define PTR_ERR(ptr)    ((long)(ptr))
 807 #define IS_ERR(ptr)     ((unsigned long)(ptr) > (unsigned long)(-1000))
 808
 809 extern struct dentry * lookup_dentry(const char *, struct dentry *, unsigned int);
 810 extern struct dentry * __namei(const char *, unsigned int);
 811
 812 #define namei(pathname)         __namei(pathname, 1)
 813 #define lnamei(pathname)        __namei(pathname, 0)
 814
 815 extern void iput(struct inode *);
 816 extern struct inode * iget(struct super_block *, unsigned long);
 817 extern void clear_inode(struct inode *);
 818 extern struct inode * get_empty_inode(void);
 819
 820 extern void insert_inode_hash(struct inode *);
 821 extern void remove_inode_hash(struct inode *);
 822 extern struct file * get_empty_filp(void);
 823 extern struct buffer_head * get_hash_table(kdev_t, int, int);
 824 extern struct buffer_head * getblk(kdev_t, int, int);
 825 extern struct buffer_head * find_buffer(kdev_t dev, int block, int size);
 826 extern void ll_rw_block(int, int, struct buffer_head * bh[]);
 827 extern int is_read_only(kdev_t);
 828 extern void __brelse(struct buffer_head *);
 829 extern inline void brelse(struct buffer_head *buf)
 830 {
 831         if (buf)
 832                 __brelse(buf);
 833 }
 834 extern void __bforget(struct buffer_head *buf);
 835 extern inline void bforget(struct buffer_head *buf)
 836 {
 837         if (buf)
 838                 __bforget(buf);
 839 }
 840 extern void set_blocksize(kdev_t dev, int size);
 841 extern unsigned int get_hardblocksize(kdev_t dev);
 842 extern struct buffer_head * bread(kdev_t dev, int block, int size);
 843 extern struct buffer_head * breada(kdev_t dev,int block, int size,
 844                                    unsigned int pos, unsigned int filesize);
 845
 846 extern int brw_page(int, struct page *, kdev_t, int [], int, int);
 847
 848 extern int generic_readpage(struct file *, struct page *);
 849 extern int generic_file_mmap(struct file *, struct vm_area_struct *);
 850 extern ssize_t generic_file_read(struct file *, char *, size_t, loff_t *);
 851 extern ssize_t generic_file_write(struct file *, const char*, size_t, loff_t*);
 852
 853 extern struct super_block *get_super(kdev_t dev);
 854 extern void put_super(kdev_t dev);
 855 unsigned long generate_cluster(kdev_t dev, int b[], int size);
 856 unsigned long generate_cluster_swab32(kdev_t dev, int b[], int size);
 857 extern kdev_t ROOT_DEV;
 858
 859 extern void show_buffers(void);
 860 extern void mount_root(void);
 861
 862 #ifdef CONFIG_BLK_DEV_INITRD
 863 extern kdev_t real_root_dev;
 864 extern int change_root(kdev_t new_root_dev,const char *put_old);
 865 #endif
 866
 867 extern ssize_t char_read(struct file *, char *, size_t, loff_t *);
 868 extern ssize_t block_read(struct file *, char *, size_t, loff_t *);
 869 extern int read_ahead[];
 870
 871 extern ssize_t char_write(struct file *, const char *, size_t, loff_t *);
 872 extern ssize_t block_write(struct file *, const char *, size_t, loff_t *);
 873
 874 extern int block_fsync(struct file *, struct dentry *dir);
 875 extern int file_fsync(struct file *, struct dentry *dir);
 876
 877 extern int inode_change_ok(struct inode *, struct iattr *);
 878 extern void inode_setattr(struct inode *, struct iattr *);
 879
 880 /* kludge to get SCSI modules working */
 881 #include <linux/minix_fs.h>
 882 #include <linux/minix_fs_sb.h>
 883
 884 #endif /* __KERNEL__ */
 885
 886 #endif