root/include/linux/fs.h

/* */

INCLUDED FROM

DEFINITIONS

1. buffer_uptodate
2. buffer_dirty
3. buffer_locked
4. buffer_req
5. buffer_touched
6. buffer_has_aged
7. buffer_protected
8. mark_buffer_uptodate
9. mark_buffer_clean
10. mark_buffer_dirty
11. brelse
12. bforget
13. iget

   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/linkage.h>
  10 #include <linux/limits.h>
  11 #include <linux/wait.h>
  12 #include <linux/types.h>
  13 #include <linux/vfs.h>
  14 #include <linux/net.h>
  15 #include <linux/kdev_t.h>
  16 #include <linux/ioctl.h>
  17 
  18 /*
  19  * It's silly to have NR_OPEN bigger than NR_FILE, but I'll fix
  20  * that later. Anyway, now the file code is no longer dependent
  21  * on bitmaps in unsigned longs, but uses the new fd_set structure..
  22  *
  23  * Some programs (notably those using select()) may have to be 
  24  * recompiled to take full advantage of the new limits..
  25  */
  26 
  27 /* Fixed constants first: */
  28 #undef NR_OPEN
  29 #define NR_OPEN 256
  30 
  31 #define NR_SUPER 64
  32 #define NR_IHASH 131
  33 #define BLOCK_SIZE 1024
  34 #define BLOCK_SIZE_BITS 10
  35 
  36 /* And dynamically-tunable limits and defaults: */
  37 extern int max_inodes, nr_inodes;
  38 extern int max_files, nr_files;
  39 #define NR_INODE 2048   /* this should be bigger than NR_FILE */
  40 #define NR_FILE 1024    /* this can well be larger on a larger system */
  41 
  42 #define MAY_EXEC 1
  43 #define MAY_WRITE 2
  44 #define MAY_READ 4
  45 
  46 #define FMODE_READ 1
  47 #define FMODE_WRITE 2
  48 
  49 #define READ 0
  50 #define WRITE 1
  51 #define READA 2         /* read-ahead - don't pause */
  52 #define WRITEA 3        /* "write-ahead" - silly, but somewhat useful */
  53 
  54 #ifndef NULL
  55 #define NULL ((void *) 0)
  56 #endif
  57 
  58 #define NIL_FILP        ((struct file *)0)
  59 #define SEL_IN          1
  60 #define SEL_OUT         2
  61 #define SEL_EX          4
  62 
  63 /*
  64  * These are the fs-independent mount-flags: up to 16 flags are supported
  65  */
  66 #define MS_RDONLY        1      /* Mount read-only */
  67 #define MS_NOSUID        2      /* Ignore suid and sgid bits */
  68 #define MS_NODEV         4      /* Disallow access to device special files */
  69 #define MS_NOEXEC        8      /* Disallow program execution */
  70 #define MS_SYNCHRONOUS  16      /* Writes are synced at once */
  71 #define MS_REMOUNT      32      /* Alter flags of a mounted FS */
  72 #define S_WRITE         128     /* Write on file/directory/symlink */
  73 #define S_APPEND        256     /* Append-only file */
  74 #define S_IMMUTABLE     512     /* Immutable file */
  75 
  76 /*
  77  * Flags that can be altered by MS_REMOUNT
  78  */
  79 #define MS_RMT_MASK (MS_RDONLY)
  80 
  81 /*
  82  * Magic mount flag number. Has to be or-ed to the flag values.
  83  */
  84 #define MS_MGC_VAL 0xC0ED0000   /* magic flag number to indicate "new" flags */
  85 #define MS_MGC_MSK 0xffff0000   /* magic flag number mask */
  86 
  87 /*
  88  * Note that read-only etc flags are inode-specific: setting some file-system
  89  * flags just means all the inodes inherit those flags by default. It might be
  90  * possible to override it selectively if you really wanted to with some
  91  * ioctl() that is not currently implemented.
  92  *
  93  * Exception: MS_RDONLY is always applied to the entire file system.
  94  */
  95 #define IS_RDONLY(inode) (((inode)->i_sb) && ((inode)->i_sb->s_flags & MS_RDONLY))
  96 #define IS_NOSUID(inode) ((inode)->i_flags & MS_NOSUID)
  97 #define IS_NODEV(inode) ((inode)->i_flags & MS_NODEV)
  98 #define IS_NOEXEC(inode) ((inode)->i_flags & MS_NOEXEC)
  99 #define IS_SYNC(inode) ((inode)->i_flags & MS_SYNCHRONOUS)
 100 
 101 #define IS_WRITABLE(inode) ((inode)->i_flags & S_WRITE)
 102 #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
 103 #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
 104 
 105 /* the read-only stuff doesn't really belong here, but any other place is
 106    probably as bad and I don't want to create yet another include file. */
 107 
 108 #define BLKROSET   _IO(0x12,93) /* set device read-only (0 = read-write) */
 109 #define BLKROGET   _IO(0x12,94) /* get read-only status (0 = read_write) */
 110 #define BLKRRPART  _IO(0x12,95) /* re-read partition table */
 111 #define BLKGETSIZE _IO(0x12,96) /* return device size */
 112 #define BLKFLSBUF  _IO(0x12,97) /* flush buffer cache */
 113 #define BLKRASET   _IO(0x12,98) /* Set read ahead for block device */
 114 #define BLKRAGET   _IO(0x12,99) /* get current read ahead setting */
 115 
 116 #define BMAP_IOCTL 1            /* obsolete - kept for compatibility */
 117 #define FIBMAP     _IO(0x00,1)  /* bmap access */
 118 #define FIGETBSZ   _IO(0x00,2)  /* get the block size used for bmap */
 119 
 120 #ifdef __KERNEL__
 121 
 122 #include <asm/bitops.h>
 123 
 124 extern void buffer_init(void);
 125 extern unsigned long inode_init(unsigned long start, unsigned long end);
 126 extern unsigned long file_table_init(unsigned long start, unsigned long end);
 127 extern unsigned long name_cache_init(unsigned long start, unsigned long end);
 128 
 129 typedef char buffer_block[BLOCK_SIZE];
 130 
 131 /* bh state bits */
 132 #define BH_Uptodate     0       /* 1 if the buffer contains valid data */
 133 #define BH_Dirty        1       /* 1 if the buffer is dirty */
 134 #define BH_Lock         2       /* 1 if the buffer is locked */
 135 #define BH_Req          3       /* 0 if the buffer has been invalidated */
 136 #define BH_Touched      4       /* 1 if the buffer has been touched (aging) */
 137 #define BH_Has_aged     5       /* 1 if the buffer has been aged (aging) */
 138 #define BH_Protected    6       /* 1 if the buffer is protected */
 139 
 140 struct buffer_head {
 141         char * b_data;                  /* pointer to data block (1024 bytes) */
 142         unsigned long b_size;           /* block size */
 143         unsigned long b_blocknr;        /* block number */
 144         kdev_t b_dev;                   /* device (B_FREE = free) */
 145         unsigned long b_state;          /* buffer state bitmap (see above) */
 146         unsigned int b_count;           /* users using this block */
 147         unsigned int b_list;            /* List that this buffer appears */
 148         unsigned long b_flushtime;      /* Time when this (dirty) buffer
 149                                          * should be written */
 150         unsigned long b_lru_time;       /* Time when this buffer was 
 151                                          * last used. */
 152         struct wait_queue * b_wait;
 153         struct buffer_head * b_prev;            /* doubly linked list of hash-queue */
 154         struct buffer_head * b_next;
 155         struct buffer_head * b_prev_free;       /* doubly linked list of buffers */
 156         struct buffer_head * b_next_free;
 157         struct buffer_head * b_this_page;       /* circular list of buffers in one page */
 158         struct buffer_head * b_reqnext;         /* request queue */
 159 };
 160 
 161 static inline int buffer_uptodate(struct buffer_head * bh)
     /*  */
 162 {
 163         return test_bit(BH_Uptodate, &bh->b_state);
 164 }       
 165 
 166 static inline int buffer_dirty(struct buffer_head * bh)
     /*  */
 167 {
 168         return test_bit(BH_Dirty, &bh->b_state);
 169 }
 170 
 171 static inline int buffer_locked(struct buffer_head * bh)
     /*  */
 172 {
 173         return test_bit(BH_Lock, &bh->b_state);
 174 }
 175 
 176 static inline int buffer_req(struct buffer_head * bh)
     /*  */
 177 {
 178         return test_bit(BH_Req, &bh->b_state);
 179 }
 180 
 181 static inline int buffer_touched(struct buffer_head * bh)
     /*  */
 182 {
 183         return test_bit(BH_Touched, &bh->b_state);
 184 }
 185 
 186 static inline int buffer_has_aged(struct buffer_head * bh)
     /*  */
 187 {
 188         return test_bit(BH_Has_aged, &bh->b_state);
 189 }
 190 
 191 static inline int buffer_protected(struct buffer_head * bh)
     /*  */
 192 {
 193         return test_bit(BH_Protected, &bh->b_state);
 194 }
 195 
 196 #include <linux/pipe_fs_i.h>
 197 #include <linux/minix_fs_i.h>
 198 #include <linux/ext_fs_i.h>
 199 #include <linux/ext2_fs_i.h>
 200 #include <linux/hpfs_fs_i.h>
 201 #include <linux/msdos_fs_i.h>
 202 #include <linux/umsdos_fs_i.h>
 203 #include <linux/iso_fs_i.h>
 204 #include <linux/nfs_fs_i.h>
 205 #include <linux/xia_fs_i.h>
 206 #include <linux/sysv_fs_i.h>
 207 
 208 /*
 209  * Attribute flags.  These should be or-ed together to figure out what
 210  * has been changed!
 211  */
 212 #define ATTR_MODE       1
 213 #define ATTR_UID        2
 214 #define ATTR_GID        4
 215 #define ATTR_SIZE       8
 216 #define ATTR_ATIME      16
 217 #define ATTR_MTIME      32
 218 #define ATTR_CTIME      64
 219 #define ATTR_ATIME_SET  128
 220 #define ATTR_MTIME_SET  256
 221 
 222 /*
 223  * This is the Inode Attributes structure, used for notify_change().  It
 224  * uses the above definitions as flags, to know which values have changed.
 225  * Also, in this manner, a Filesystem can look at only the values it cares
 226  * about.  Basically, these are the attributes that the VFS layer can
 227  * request to change from the FS layer.
 228  *
 229  * Derek Atkins <warlord@MIT.EDU> 94-10-20
 230  */
 231 struct iattr {
 232         unsigned int    ia_valid;
 233         umode_t         ia_mode;
 234         uid_t           ia_uid;
 235         gid_t           ia_gid;
 236         off_t           ia_size;
 237         time_t          ia_atime;
 238         time_t          ia_mtime;
 239         time_t          ia_ctime;
 240 };
 241 
 242 #include <linux/quota.h>
 243 
 244 struct inode {
 245         kdev_t          i_dev;
 246         unsigned long   i_ino;
 247         umode_t         i_mode;
 248         nlink_t         i_nlink;
 249         uid_t           i_uid;
 250         gid_t           i_gid;
 251         kdev_t          i_rdev;
 252         off_t           i_size;
 253         time_t          i_atime;
 254         time_t          i_mtime;
 255         time_t          i_ctime;
 256         unsigned long   i_blksize;
 257         unsigned long   i_blocks;
 258         unsigned long   i_version;
 259         unsigned long   i_nrpages;
 260         struct semaphore i_sem;
 261         struct inode_operations *i_op;
 262         struct super_block *i_sb;
 263         struct wait_queue *i_wait;
 264         struct file_lock *i_flock;
 265         struct vm_area_struct *i_mmap;
 266         struct page *i_pages;
 267         struct dquot *i_dquot[MAXQUOTAS];
 268         struct inode *i_next, *i_prev;
 269         struct inode *i_hash_next, *i_hash_prev;
 270         struct inode *i_bound_to, *i_bound_by;
 271         struct inode *i_mount;
 272         unsigned short i_count;
 273         unsigned short i_flags;
 274         unsigned char i_lock;
 275         unsigned char i_dirt;
 276         unsigned char i_pipe;
 277         unsigned char i_sock;
 278         unsigned char i_seek;
 279         unsigned char i_update;
 280         unsigned short i_writecount;
 281         union {
 282                 struct pipe_inode_info pipe_i;
 283                 struct minix_inode_info minix_i;
 284                 struct ext_inode_info ext_i;
 285                 struct ext2_inode_info ext2_i;
 286                 struct hpfs_inode_info hpfs_i;
 287                 struct msdos_inode_info msdos_i;
 288                 struct umsdos_inode_info umsdos_i;
 289                 struct iso_inode_info isofs_i;
 290                 struct nfs_inode_info nfs_i;
 291                 struct xiafs_inode_info xiafs_i;
 292                 struct sysv_inode_info sysv_i;
 293                 struct socket socket_i;
 294                 void * generic_ip;
 295         } u;
 296 };
 297 
 298 struct file {
 299         mode_t f_mode;
 300         loff_t f_pos;
 301         unsigned short f_flags;
 302         unsigned short f_count;
 303         off_t f_reada;
 304         struct file *f_next, *f_prev;
 305         int f_owner;            /* pid or -pgrp where SIGIO should be sent */
 306         struct inode * f_inode;
 307         struct file_operations * f_op;
 308         unsigned long f_version;
 309         void *private_data;     /* needed for tty driver, and maybe others */
 310 };
 311 
 312 struct file_lock {
 313         struct file_lock *fl_next;      /* singly linked list for this inode  */
 314         struct file_lock *fl_nextlink;  /* doubly linked list of all locks */
 315         struct file_lock *fl_prevlink;  /* used to simplify lock removal */
 316         struct file_lock *fl_block;
 317         struct task_struct *fl_owner;
 318         struct wait_queue *fl_wait;
 319         struct file *fl_file;
 320         char fl_flags;
 321         char fl_type;
 322         off_t fl_start;
 323         off_t fl_end;
 324 };
 325 
 326 struct fasync_struct {
 327         int    magic;
 328         struct fasync_struct    *fa_next; /* singly linked list */
 329         struct file             *fa_file;
 330 };
 331 
 332 #define FASYNC_MAGIC 0x4601
 333 
 334 extern int fasync_helper(struct inode *, struct file *, int, struct fasync_struct **);
 335 
 336 #include <linux/minix_fs_sb.h>
 337 #include <linux/ext_fs_sb.h>
 338 #include <linux/ext2_fs_sb.h>
 339 #include <linux/hpfs_fs_sb.h>
 340 #include <linux/msdos_fs_sb.h>
 341 #include <linux/iso_fs_sb.h>
 342 #include <linux/nfs_fs_sb.h>
 343 #include <linux/xia_fs_sb.h>
 344 #include <linux/sysv_fs_sb.h>
 345 
 346 struct super_block {
 347         kdev_t s_dev;
 348         unsigned long s_blocksize;
 349         unsigned char s_blocksize_bits;
 350         unsigned char s_lock;
 351         unsigned char s_rd_only;
 352         unsigned char s_dirt;
 353         struct file_system_type *s_type;
 354         struct super_operations *s_op;
 355         struct dquot_operations *dq_op;
 356         unsigned long s_flags;
 357         unsigned long s_magic;
 358         unsigned long s_time;
 359         struct inode * s_covered;
 360         struct inode * s_mounted;
 361         struct wait_queue * s_wait;
 362         union {
 363                 struct minix_sb_info minix_sb;
 364                 struct ext_sb_info ext_sb;
 365                 struct ext2_sb_info ext2_sb;
 366                 struct hpfs_sb_info hpfs_sb;
 367                 struct msdos_sb_info msdos_sb;
 368                 struct isofs_sb_info isofs_sb;
 369                 struct nfs_sb_info nfs_sb;
 370                 struct xiafs_sb_info xiafs_sb;
 371                 struct sysv_sb_info sysv_sb;
 372                 void *generic_sbp;
 373         } u;
 374 };
 375 
 376 /*
 377  * This is the "filldir" function type, used by readdir() to let
 378  * the kernel specify what kind of dirent layout it wants to have.
 379  * This allows the kernel to read directories into kernel space or
 380  * to have different dirent layouts depending on the binary type.
 381  */
 382 typedef int (*filldir_t)(void *, const char *, int, off_t, ino_t);
 383         
 384 struct file_operations {
 385         int (*lseek) (struct inode *, struct file *, off_t, int);
 386         int (*read) (struct inode *, struct file *, char *, int);
 387         int (*write) (struct inode *, struct file *, const char *, int);
 388         int (*readdir) (struct inode *, struct file *, void *, filldir_t);
 389         int (*select) (struct inode *, struct file *, int, select_table *);
 390         int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
 391         int (*mmap) (struct inode *, struct file *, struct vm_area_struct *);
 392         int (*open) (struct inode *, struct file *);
 393         void (*release) (struct inode *, struct file *);
 394         int (*fsync) (struct inode *, struct file *);
 395         int (*fasync) (struct inode *, struct file *, int);
 396         int (*check_media_change) (kdev_t dev);
 397         int (*revalidate) (kdev_t dev);
 398 };
 399 
 400 struct inode_operations {
 401         struct file_operations * default_file_ops;
 402         int (*create) (struct inode *,const char *,int,int,struct inode **);
 403         int (*lookup) (struct inode *,const char *,int,struct inode **);
 404         int (*link) (struct inode *,struct inode *,const char *,int);
 405         int (*unlink) (struct inode *,const char *,int);
 406         int (*symlink) (struct inode *,const char *,int,const char *);
 407         int (*mkdir) (struct inode *,const char *,int,int);
 408         int (*rmdir) (struct inode *,const char *,int);
 409         int (*mknod) (struct inode *,const char *,int,int,int);
 410         int (*rename) (struct inode *,const char *,int,struct inode *,const char *,int);
 411         int (*readlink) (struct inode *,char *,int);
 412         int (*follow_link) (struct inode *,struct inode *,int,int,struct inode **);
 413         int (*readpage) (struct inode *, struct page *);
 414         int (*writepage) (struct inode *, struct page *);
 415         int (*bmap) (struct inode *,int);
 416         void (*truncate) (struct inode *);
 417         int (*permission) (struct inode *, int);
 418         int (*smap) (struct inode *,int);
 419 };
 420 
 421 struct super_operations {
 422         void (*read_inode) (struct inode *);
 423         int (*notify_change) (struct inode *, struct iattr *);
 424         void (*write_inode) (struct inode *);
 425         void (*put_inode) (struct inode *);
 426         void (*put_super) (struct super_block *);
 427         void (*write_super) (struct super_block *);
 428         void (*statfs) (struct super_block *, struct statfs *, int);
 429         int (*remount_fs) (struct super_block *, int *, char *);
 430 };
 431 
 432 struct dquot_operations {
 433         void (*initialize) (struct inode *, short);
 434         void (*drop) (struct inode *);
 435         int (*alloc_block) (const struct inode *, unsigned long);
 436         int (*alloc_inode) (const struct inode *, unsigned long);
 437         void (*free_block) (const struct inode *, unsigned long);
 438         void (*free_inode) (const struct inode *, unsigned long);
 439         int (*transfer) (struct inode *, struct iattr *, char);
 440 };
 441 
 442 struct file_system_type {
 443         struct super_block *(*read_super) (struct super_block *, void *, int);
 444         const char *name;
 445         int requires_dev;
 446         struct file_system_type * next;
 447 };
 448 
 449 extern int register_filesystem(struct file_system_type *);
 450 extern int unregister_filesystem(struct file_system_type *);
 451 
 452 asmlinkage int sys_open(const char *, int, int);
 453 asmlinkage int sys_close(unsigned int);         /* yes, it's really unsigned */
 454 
 455 extern void kill_fasync(struct fasync_struct *fa, int sig);
 456 
 457 extern int getname(const char * filename, char **result);
 458 extern void putname(char * name);
 459 extern int do_truncate(struct inode *, unsigned long);
 460 extern int register_blkdev(unsigned int, const char *, struct file_operations *);
 461 extern int unregister_blkdev(unsigned int major, const char * name);
 462 extern int blkdev_open(struct inode * inode, struct file * filp);
 463 extern struct file_operations def_blk_fops;
 464 extern struct inode_operations blkdev_inode_operations;
 465 
 466 extern int register_chrdev(unsigned int, const char *, struct file_operations *);
 467 extern int unregister_chrdev(unsigned int major, const char * name);
 468 extern int chrdev_open(struct inode * inode, struct file * filp);
 469 extern struct file_operations def_chr_fops;
 470 extern struct inode_operations chrdev_inode_operations;
 471 
 472 extern void init_fifo(struct inode * inode);
 473 
 474 extern struct file_operations connecting_fifo_fops;
 475 extern struct file_operations read_fifo_fops;
 476 extern struct file_operations write_fifo_fops;
 477 extern struct file_operations rdwr_fifo_fops;
 478 extern struct file_operations read_pipe_fops;
 479 extern struct file_operations write_pipe_fops;
 480 extern struct file_operations rdwr_pipe_fops;
 481 
 482 extern struct file_system_type *get_fs_type(const char *name);
 483 
 484 extern int fs_may_mount(kdev_t dev);
 485 extern int fs_may_umount(kdev_t dev, struct inode * mount_root);
 486 extern int fs_may_remount_ro(kdev_t dev);
 487 
 488 extern struct file *first_file;
 489 extern int nr_files;
 490 extern struct super_block super_blocks[NR_SUPER];
 491 
 492 extern void refile_buffer(struct buffer_head * buf);
 493 extern void set_writetime(struct buffer_head * buf, int flag);
 494 extern void refill_freelist(int size);
 495 extern int try_to_free_buffer(struct buffer_head*, struct buffer_head**, int);
 496 
 497 extern struct buffer_head ** buffer_pages;
 498 extern int nr_buffers;
 499 extern int buffermem;
 500 extern int nr_buffer_heads;
 501 
 502 #define BUF_CLEAN 0
 503 #define BUF_UNSHARED 1 /* Buffers that were shared but are not any more */
 504 #define BUF_LOCKED 2   /* Buffers scheduled for write */
 505 #define BUF_LOCKED1 3  /* Supers, inodes */
 506 #define BUF_DIRTY 4    /* Dirty buffers, not yet scheduled for write */
 507 #define BUF_SHARED 5   /* Buffers shared */
 508 #define NR_LIST 6
 509 
 510 extern inline void mark_buffer_uptodate(struct buffer_head * bh, int on)
     /*  */
 511 {
 512         if (on)
 513                 set_bit(BH_Uptodate, &bh->b_state);
 514         else
 515                 clear_bit(BH_Uptodate, &bh->b_state);
 516 }
 517 
 518 extern inline void mark_buffer_clean(struct buffer_head * bh)
     /*  */
 519 {
 520         if (clear_bit(BH_Dirty, &bh->b_state)) {
 521                 if (bh->b_list == BUF_DIRTY)
 522                         refile_buffer(bh);
 523         }
 524 }
 525 
 526 extern inline void mark_buffer_dirty(struct buffer_head * bh, int flag)
     /*  */
 527 {
 528         if (!set_bit(BH_Dirty, &bh->b_state)) {
 529                 set_writetime(bh, flag);
 530                 if (bh->b_list != BUF_DIRTY)
 531                         refile_buffer(bh);
 532         }
 533 }
 534 
 535 extern int check_disk_change(kdev_t dev);
 536 extern void invalidate_inodes(kdev_t dev);
 537 extern void invalidate_inode_pages(struct inode *, unsigned long);
 538 extern void invalidate_buffers(kdev_t dev);
 539 extern int floppy_is_wp(int minor);
 540 extern void sync_inodes(kdev_t dev);
 541 extern void sync_dev(kdev_t dev);
 542 extern int fsync_dev(kdev_t dev);
 543 extern void sync_supers(kdev_t dev);
 544 extern int bmap(struct inode * inode,int block);
 545 extern int notify_change(struct inode *, struct iattr *);
 546 extern int namei(const char * pathname, struct inode ** res_inode);
 547 extern int lnamei(const char * pathname, struct inode ** res_inode);
 548 extern int permission(struct inode * inode,int mask);
 549 extern int get_write_access(struct inode *inode);
 550 extern void put_write_access(struct inode *inode);
 551 extern int open_namei(const char * pathname, int flag, int mode,
 552         struct inode ** res_inode, struct inode * base);
 553 extern int do_mknod(const char * filename, int mode, dev_t dev);
 554 extern int do_pipe(int *);
 555 extern void iput(struct inode * inode);
 556 extern struct inode * __iget(struct super_block * sb,int nr,int crsmnt);
 557 extern struct inode * get_empty_inode(void);
 558 extern void insert_inode_hash(struct inode *);
 559 extern void clear_inode(struct inode *);
 560 extern struct inode * get_pipe_inode(void);
 561 extern struct file * get_empty_filp(void);
 562 extern int close_fp(struct file *filp);
 563 extern struct buffer_head * get_hash_table(kdev_t dev, int block, int size);
 564 extern struct buffer_head * getblk(kdev_t dev, int block, int size);
 565 extern void ll_rw_block(int rw, int nr, struct buffer_head * bh[]);
 566 extern void ll_rw_page(int rw, kdev_t dev, unsigned long nr, char * buffer);
 567 extern void ll_rw_swap_file(int rw, kdev_t dev, unsigned int *b, int nb, char *buffer);
 568 extern int is_read_only(kdev_t dev);
 569 extern void __brelse(struct buffer_head *buf);
 570 extern inline void brelse(struct buffer_head *buf)
     /*  */
 571 {
 572         if (buf)
 573                 __brelse(buf);
 574 }
 575 extern void __bforget(struct buffer_head *buf);
 576 extern inline void bforget(struct buffer_head *buf)
     /*  */
 577 {
 578         if (buf)
 579                 __bforget(buf);
 580 }
 581 extern void set_blocksize(kdev_t dev, int size);
 582 extern struct buffer_head * bread(kdev_t dev, int block, int size);
 583 extern struct buffer_head * breada(kdev_t dev,int block, int size, 
 584                                    unsigned int pos, unsigned int filesize);
 585 
 586 extern int generic_readpage(struct inode *, struct page *);
 587 extern int generic_file_read(struct inode *, struct file *, char *, int);
 588 extern int generic_mmap(struct inode *, struct file *, struct vm_area_struct *);
 589 
 590 extern void bwrite_page(unsigned long addr,kdev_t dev,int b[],int size);
 591 extern void put_super(kdev_t dev);
 592 unsigned long generate_cluster(kdev_t dev, int b[], int size);
 593 extern kdev_t ROOT_DEV;
 594 
 595 extern void show_buffers(void);
 596 extern void mount_root(void);
 597 
 598 extern int char_read(struct inode *, struct file *, char *, int);
 599 extern int block_read(struct inode *, struct file *, char *, int);
 600 extern int read_ahead[];
 601 
 602 extern int char_write(struct inode *, struct file *, const char *, int);
 603 extern int block_write(struct inode *, struct file *, const char *, int);
 604 
 605 extern int block_fsync(struct inode *, struct file *);
 606 extern int file_fsync(struct inode *, struct file *);
 607 
 608 extern void dcache_add(struct inode *, const char *, int, unsigned long);
 609 extern int dcache_lookup(struct inode *, const char *, int, unsigned long *);
 610 
 611 extern int inode_change_ok(struct inode *, struct iattr *);
 612 extern void inode_setattr(struct inode *, struct iattr *);
 613 
 614 extern inline struct inode * iget(struct super_block * sb,int nr)
     /*  */
 615 {
 616         return __iget(sb, nr, 1);
 617 }
 618 
 619 #endif /* __KERNEL__ */
 620 
 621 #endif

/* */