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. locks_verify_locked
9. locks_verify_area
10. mark_buffer_clean
11. mark_buffer_dirty
12. brelse
13. bforget
14. 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/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 
  19 /*
  20  * It's silly to have NR_OPEN bigger than NR_FILE, but I'll fix
  21  * that later. Anyway, now the file code is no longer dependent
  22  * on bitmaps in unsigned longs, but uses the new fd_set structure..
  23  *
  24  * Some programs (notably those using select()) may have to be 
  25  * recompiled to take full advantage of the new limits..
  26  */
  27 
  28 /* Fixed constants first: */
  29 #undef NR_OPEN
  30 #define NR_OPEN 256
  31 
  32 #define NR_SUPER 64
  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 3072   /* 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 #define BH_FreeOnIO     7       /* 1 to discard the buffer_head after IO */
 140 
 141 /*
 142  * Try to keep the most commonly used fields in single cache lines (16
 143  * bytes) to improve performance.  This ordering should be
 144  * particularly beneficial on 32-bit processors.
 145  * 
 146  * We use the first 16 bytes for the data which is used in searches
 147  * over the block hash lists (ie. getblk(), find_buffer() and
 148  * friends).
 149  * 
 150  * The second 16 bytes we use for lru buffer scans, as used by
 151  * sync_buffers() and refill_freelist().  -- sct
 152  */
 153 struct buffer_head {
 154         /* First cache line: */
 155         unsigned long b_blocknr;        /* block number */
 156         kdev_t b_dev;                   /* device (B_FREE = free) */
 157         kdev_t b_rdev;                  /* Real device */
 158         unsigned long b_rsector;        /* Real buffer location on disk */
 159         struct buffer_head * b_next;    /* Hash queue list */
 160         struct buffer_head * b_this_page;       /* circular list of buffers in one page */
 161 
 162         /* Second cache line: */
 163         unsigned long b_state;          /* buffer state bitmap (see above) */
 164         struct buffer_head * b_next_free;
 165         unsigned int b_count;           /* users using this block */
 166         unsigned long b_size;           /* block size */
 167 
 168         /* Non-performance-critical data follows. */
 169         char * b_data;                  /* pointer to data block (1024 bytes) */
 170         unsigned int b_list;            /* List that this buffer appears */
 171         unsigned long b_flushtime;      /* Time when this (dirty) buffer
 172                                          * should be written */
 173         unsigned long b_lru_time;       /* Time when this buffer was 
 174                                          * last used. */
 175         struct wait_queue * b_wait;
 176         struct buffer_head * b_prev;            /* doubly linked list of hash-queue */
 177         struct buffer_head * b_prev_free;       /* doubly linked list of buffers */
 178         struct buffer_head * b_reqnext;         /* request queue */
 179 };
 180 
 181 static inline int buffer_uptodate(struct buffer_head * bh)
     /*  */
 182 {
 183         return test_bit(BH_Uptodate, &bh->b_state);
 184 }       
 185 
 186 static inline int buffer_dirty(struct buffer_head * bh)
     /*  */
 187 {
 188         return test_bit(BH_Dirty, &bh->b_state);
 189 }
 190 
 191 static inline int buffer_locked(struct buffer_head * bh)
     /*  */
 192 {
 193         return test_bit(BH_Lock, &bh->b_state);
 194 }
 195 
 196 static inline int buffer_req(struct buffer_head * bh)
     /*  */
 197 {
 198         return test_bit(BH_Req, &bh->b_state);
 199 }
 200 
 201 static inline int buffer_touched(struct buffer_head * bh)
     /*  */
 202 {
 203         return test_bit(BH_Touched, &bh->b_state);
 204 }
 205 
 206 static inline int buffer_has_aged(struct buffer_head * bh)
     /*  */
 207 {
 208         return test_bit(BH_Has_aged, &bh->b_state);
 209 }
 210 
 211 static inline int buffer_protected(struct buffer_head * bh)
     /*  */
 212 {
 213         return test_bit(BH_Protected, &bh->b_state);
 214 }
 215 
 216 #include <linux/pipe_fs_i.h>
 217 #include <linux/minix_fs_i.h>
 218 #include <linux/ext_fs_i.h>
 219 #include <linux/ext2_fs_i.h>
 220 #include <linux/hpfs_fs_i.h>
 221 #include <linux/msdos_fs_i.h>
 222 #include <linux/umsdos_fs_i.h>
 223 #include <linux/iso_fs_i.h>
 224 #include <linux/nfs_fs_i.h>
 225 #include <linux/xia_fs_i.h>
 226 #include <linux/sysv_fs_i.h>
 227 #include <linux/affs_fs_i.h>
 228 #include <linux/ufs_fs_i.h>
 229 
 230 /*
 231  * Attribute flags.  These should be or-ed together to figure out what
 232  * has been changed!
 233  */
 234 #define ATTR_MODE       1
 235 #define ATTR_UID        2
 236 #define ATTR_GID        4
 237 #define ATTR_SIZE       8
 238 #define ATTR_ATIME      16
 239 #define ATTR_MTIME      32
 240 #define ATTR_CTIME      64
 241 #define ATTR_ATIME_SET  128
 242 #define ATTR_MTIME_SET  256
 243 #define ATTR_FORCE      512     /* Not a change, but a change it */
 244 
 245 /*
 246  * This is the Inode Attributes structure, used for notify_change().  It
 247  * uses the above definitions as flags, to know which values have changed.
 248  * Also, in this manner, a Filesystem can look at only the values it cares
 249  * about.  Basically, these are the attributes that the VFS layer can
 250  * request to change from the FS layer.
 251  *
 252  * Derek Atkins <warlord@MIT.EDU> 94-10-20
 253  */
 254 struct iattr {
 255         unsigned int    ia_valid;
 256         umode_t         ia_mode;
 257         uid_t           ia_uid;
 258         gid_t           ia_gid;
 259         off_t           ia_size;
 260         time_t          ia_atime;
 261         time_t          ia_mtime;
 262         time_t          ia_ctime;
 263 };
 264 
 265 #include <linux/quota.h>
 266 
 267 struct inode {
 268         kdev_t          i_dev;
 269         unsigned long   i_ino;
 270         umode_t         i_mode;
 271         nlink_t         i_nlink;
 272         uid_t           i_uid;
 273         gid_t           i_gid;
 274         kdev_t          i_rdev;
 275         off_t           i_size;
 276         time_t          i_atime;
 277         time_t          i_mtime;
 278         time_t          i_ctime;
 279         unsigned long   i_blksize;
 280         unsigned long   i_blocks;
 281         unsigned long   i_version;
 282         unsigned long   i_nrpages;
 283         struct semaphore i_sem;
 284         struct inode_operations *i_op;
 285         struct super_block *i_sb;
 286         struct wait_queue *i_wait;
 287         struct file_lock *i_flock;
 288         struct vm_area_struct *i_mmap;
 289         struct page *i_pages;
 290         struct dquot *i_dquot[MAXQUOTAS];
 291         struct inode *i_next, *i_prev;
 292         struct inode *i_hash_next, *i_hash_prev;
 293         struct inode *i_bound_to, *i_bound_by;
 294         struct inode *i_mount;
 295         unsigned short i_count;
 296         unsigned short i_flags;
 297         unsigned char i_lock;
 298         unsigned char i_dirt;
 299         unsigned char i_pipe;
 300         unsigned char i_sock;
 301         unsigned char i_seek;
 302         unsigned char i_update;
 303         unsigned short i_writecount;
 304         union {
 305                 struct pipe_inode_info pipe_i;
 306                 struct minix_inode_info minix_i;
 307                 struct ext_inode_info ext_i;
 308                 struct ext2_inode_info ext2_i;
 309                 struct hpfs_inode_info hpfs_i;
 310                 struct msdos_inode_info msdos_i;
 311                 struct umsdos_inode_info umsdos_i;
 312                 struct iso_inode_info isofs_i;
 313                 struct nfs_inode_info nfs_i;
 314                 struct xiafs_inode_info xiafs_i;
 315                 struct sysv_inode_info sysv_i;
 316                 struct affs_inode_info affs_i;
 317                 struct ufs_inode_info ufs_i;
 318                 struct socket socket_i;
 319                 void * generic_ip;
 320         } u;
 321 };
 322 
 323 struct file {
 324         mode_t f_mode;
 325         loff_t f_pos;
 326         unsigned short f_flags;
 327         unsigned short f_count;
 328         unsigned long f_reada, f_ramax, f_rapos, f_ralen, f_rawin;
 329         struct file *f_next, *f_prev;
 330         int f_owner;            /* pid or -pgrp where SIGIO should be sent */
 331         struct inode * f_inode;
 332         struct file_operations * f_op;
 333         unsigned long f_version;
 334         void *private_data;     /* needed for tty driver, and maybe others */
 335 };
 336 
 337 struct file_lock {
 338         struct file_lock *fl_next;      /* singly linked list for this inode  */
 339         struct file_lock *fl_nextlink;  /* doubly linked list of all locks */
 340         struct file_lock *fl_prevlink;  /* used to simplify lock removal */
 341         struct file_lock *fl_block;
 342         struct task_struct *fl_owner;
 343         struct wait_queue *fl_wait;
 344         struct file *fl_file;
 345         char fl_flags;
 346         char fl_type;
 347         off_t fl_start;
 348         off_t fl_end;
 349 };
 350 
 351 #include <linux/fcntl.h>
 352 
 353 extern int fcntl_getlk(unsigned int fd, struct flock *l);
 354 extern int fcntl_setlk(unsigned int fd, unsigned int cmd, struct flock *l);
 355 extern void locks_remove_locks(struct task_struct *task, struct file *filp);
 356 
 357 #include <linux/stat.h>
 358 
 359 #define FLOCK_VERIFY_READ  1
 360 #define FLOCK_VERIFY_WRITE 2
 361 
 362 extern int locks_mandatory_locked(struct inode *inode);
 363 extern inline int locks_verify_locked(struct inode *inode)
     /*  */
 364 {
 365         /* Candidates for mandatory locking have the setgid bit set
 366          * but no group execute bit -  an otherwise meaningless combination.
 367          */
 368         if ((inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
 369                 return (locks_mandatory_locked(inode));
 370         return (0);
 371 }
 372 extern int locks_mandatory_area(int read_write, struct inode *inode,
 373                                 struct file *filp, unsigned int offset,
 374                                 unsigned int count);
 375 extern inline int locks_verify_area(int read_write, struct inode *inode,
     /*  */
 376                                     struct file *filp, unsigned int offset,
 377                                     unsigned int count)
 378 {
 379         /* Candidates for mandatory locking have the setgid bit set
 380          * but no group execute bit -  an otherwise meaningless combination.
 381          */
 382         if ((inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
 383                 return (locks_mandatory_area(read_write, inode, filp, offset,
 384                                              count));
 385         return (0);
 386 }
 387 
 388 struct fasync_struct {
 389         int    magic;
 390         struct fasync_struct    *fa_next; /* singly linked list */
 391         struct file             *fa_file;
 392 };
 393 
 394 #define FASYNC_MAGIC 0x4601
 395 
 396 extern int fasync_helper(struct inode *, struct file *, int, struct fasync_struct **);
 397 
 398 #include <linux/minix_fs_sb.h>
 399 #include <linux/ext_fs_sb.h>
 400 #include <linux/ext2_fs_sb.h>
 401 #include <linux/hpfs_fs_sb.h>
 402 #include <linux/msdos_fs_sb.h>
 403 #include <linux/iso_fs_sb.h>
 404 #include <linux/nfs_fs_sb.h>
 405 #include <linux/xia_fs_sb.h>
 406 #include <linux/sysv_fs_sb.h>
 407 #include <linux/affs_fs_sb.h>
 408 #include <linux/ufs_fs_sb.h>
 409 
 410 struct super_block {
 411         kdev_t s_dev;
 412         unsigned long s_blocksize;
 413         unsigned char s_blocksize_bits;
 414         unsigned char s_lock;
 415         unsigned char s_rd_only;
 416         unsigned char s_dirt;
 417         struct file_system_type *s_type;
 418         struct super_operations *s_op;
 419         struct dquot_operations *dq_op;
 420         unsigned long s_flags;
 421         unsigned long s_magic;
 422         unsigned long s_time;
 423         struct inode * s_covered;
 424         struct inode * s_mounted;
 425         struct wait_queue * s_wait;
 426         union {
 427                 struct minix_sb_info minix_sb;
 428                 struct ext_sb_info ext_sb;
 429                 struct ext2_sb_info ext2_sb;
 430                 struct hpfs_sb_info hpfs_sb;
 431                 struct msdos_sb_info msdos_sb;
 432                 struct isofs_sb_info isofs_sb;
 433                 struct nfs_sb_info nfs_sb;
 434                 struct xiafs_sb_info xiafs_sb;
 435                 struct sysv_sb_info sysv_sb;
 436                 struct affs_sb_info affs_sb;
 437                 struct ufs_sb_info ufs_sb;
 438                 void *generic_sbp;
 439         } u;
 440 };
 441 
 442 /*
 443  * This is the "filldir" function type, used by readdir() to let
 444  * the kernel specify what kind of dirent layout it wants to have.
 445  * This allows the kernel to read directories into kernel space or
 446  * to have different dirent layouts depending on the binary type.
 447  */
 448 typedef int (*filldir_t)(void *, const char *, int, off_t, ino_t);
 449         
 450 struct file_operations {
 451         int (*lseek) (struct inode *, struct file *, off_t, int);
 452         int (*read) (struct inode *, struct file *, char *, int);
 453         int (*write) (struct inode *, struct file *, const char *, int);
 454         int (*readdir) (struct inode *, struct file *, void *, filldir_t);
 455         int (*select) (struct inode *, struct file *, int, select_table *);
 456         int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
 457         int (*mmap) (struct inode *, struct file *, struct vm_area_struct *);
 458         int (*open) (struct inode *, struct file *);
 459         void (*release) (struct inode *, struct file *);
 460         int (*fsync) (struct inode *, struct file *);
 461         int (*fasync) (struct inode *, struct file *, int);
 462         int (*check_media_change) (kdev_t dev);
 463         int (*revalidate) (kdev_t dev);
 464 };
 465 
 466 struct inode_operations {
 467         struct file_operations * default_file_ops;
 468         int (*create) (struct inode *,const char *,int,int,struct inode **);
 469         int (*lookup) (struct inode *,const char *,int,struct inode **);
 470         int (*link) (struct inode *,struct inode *,const char *,int);
 471         int (*unlink) (struct inode *,const char *,int);
 472         int (*symlink) (struct inode *,const char *,int,const char *);
 473         int (*mkdir) (struct inode *,const char *,int,int);
 474         int (*rmdir) (struct inode *,const char *,int);
 475         int (*mknod) (struct inode *,const char *,int,int,int);
 476         int (*rename) (struct inode *,const char *,int,struct inode *,const char *,int);
 477         int (*readlink) (struct inode *,char *,int);
 478         int (*follow_link) (struct inode *,struct inode *,int,int,struct inode **);
 479         int (*readpage) (struct inode *, struct page *);
 480         int (*writepage) (struct inode *, struct page *);
 481         int (*bmap) (struct inode *,int);
 482         void (*truncate) (struct inode *);
 483         int (*permission) (struct inode *, int);
 484         int (*smap) (struct inode *,int);
 485 };
 486 
 487 struct super_operations {
 488         void (*read_inode) (struct inode *);
 489         int (*notify_change) (struct inode *, struct iattr *);
 490         void (*write_inode) (struct inode *);
 491         void (*put_inode) (struct inode *);
 492         void (*put_super) (struct super_block *);
 493         void (*write_super) (struct super_block *);
 494         void (*statfs) (struct super_block *, struct statfs *, int);
 495         int (*remount_fs) (struct super_block *, int *, char *);
 496 };
 497 
 498 struct dquot_operations {
 499         void (*initialize) (struct inode *, short);
 500         void (*drop) (struct inode *);
 501         int (*alloc_block) (const struct inode *, unsigned long);
 502         int (*alloc_inode) (const struct inode *, unsigned long);
 503         void (*free_block) (const struct inode *, unsigned long);
 504         void (*free_inode) (const struct inode *, unsigned long);
 505         int (*transfer) (struct inode *, struct iattr *, char);
 506 };
 507 
 508 struct file_system_type {
 509         struct super_block *(*read_super) (struct super_block *, void *, int);
 510         const char *name;
 511         int requires_dev;
 512         struct file_system_type * next;
 513 };
 514 
 515 extern int register_filesystem(struct file_system_type *);
 516 extern int unregister_filesystem(struct file_system_type *);
 517 
 518 asmlinkage int sys_open(const char *, int, int);
 519 asmlinkage int sys_close(unsigned int);         /* yes, it's really unsigned */
 520 
 521 extern void kill_fasync(struct fasync_struct *fa, int sig);
 522 
 523 extern int getname(const char * filename, char **result);
 524 extern void putname(char * name);
 525 extern int do_truncate(struct inode *, unsigned long);
 526 extern int register_blkdev(unsigned int, const char *, struct file_operations *);
 527 extern int unregister_blkdev(unsigned int major, const char * name);
 528 extern int blkdev_open(struct inode * inode, struct file * filp);
 529 extern void blkdev_release (struct inode * inode);
 530 extern struct file_operations def_blk_fops;
 531 extern struct inode_operations blkdev_inode_operations;
 532 
 533 extern int register_chrdev(unsigned int, const char *, struct file_operations *);
 534 extern int unregister_chrdev(unsigned int major, const char * name);
 535 extern int chrdev_open(struct inode * inode, struct file * filp);
 536 extern struct file_operations def_chr_fops;
 537 extern struct inode_operations chrdev_inode_operations;
 538 
 539 extern void init_fifo(struct inode * inode);
 540 extern struct inode_operations fifo_inode_operations;
 541 
 542 extern struct file_operations connecting_fifo_fops;
 543 extern struct file_operations read_fifo_fops;
 544 extern struct file_operations write_fifo_fops;
 545 extern struct file_operations rdwr_fifo_fops;
 546 extern struct file_operations read_pipe_fops;
 547 extern struct file_operations write_pipe_fops;
 548 extern struct file_operations rdwr_pipe_fops;
 549 
 550 extern struct file_system_type *get_fs_type(const char *name);
 551 
 552 extern int fs_may_mount(kdev_t dev);
 553 extern int fs_may_umount(kdev_t dev, struct inode * mount_root);
 554 extern int fs_may_remount_ro(kdev_t dev);
 555 
 556 extern struct file *first_file;
 557 extern struct super_block super_blocks[NR_SUPER];
 558 
 559 extern void refile_buffer(struct buffer_head * buf);
 560 extern void set_writetime(struct buffer_head * buf, int flag);
 561 extern void refill_freelist(int size);
 562 extern int try_to_free_buffer(struct buffer_head*, struct buffer_head**, int);
 563 
 564 extern int nr_buffers;
 565 extern int buffermem;
 566 extern int nr_buffer_heads;
 567 
 568 #define BUF_CLEAN 0
 569 #define BUF_UNSHARED 1 /* Buffers that were shared but are not any more */
 570 #define BUF_LOCKED 2   /* Buffers scheduled for write */
 571 #define BUF_LOCKED1 3  /* Supers, inodes */
 572 #define BUF_DIRTY 4    /* Dirty buffers, not yet scheduled for write */
 573 #define BUF_SHARED 5   /* Buffers shared */
 574 #define NR_LIST 6
 575 
 576 void mark_buffer_uptodate(struct buffer_head * bh, int on);
 577 
 578 extern inline void mark_buffer_clean(struct buffer_head * bh)
     /*  */
 579 {
 580         if (clear_bit(BH_Dirty, &bh->b_state)) {
 581                 if (bh->b_list == BUF_DIRTY)
 582                         refile_buffer(bh);
 583         }
 584 }
 585 
 586 extern inline void mark_buffer_dirty(struct buffer_head * bh, int flag)
     /*  */
 587 {
 588         if (!set_bit(BH_Dirty, &bh->b_state)) {
 589                 set_writetime(bh, flag);
 590                 if (bh->b_list != BUF_DIRTY)
 591                         refile_buffer(bh);
 592         }
 593 }
 594 
 595 extern int check_disk_change(kdev_t dev);
 596 extern void invalidate_inodes(kdev_t dev);
 597 extern void invalidate_inode_pages(struct inode *);
 598 extern void invalidate_buffers(kdev_t dev);
 599 extern int floppy_is_wp(int minor);
 600 extern void sync_inodes(kdev_t dev);
 601 extern void sync_dev(kdev_t dev);
 602 extern int fsync_dev(kdev_t dev);
 603 extern void sync_supers(kdev_t dev);
 604 extern int bmap(struct inode * inode,int block);
 605 extern int notify_change(struct inode *, struct iattr *);
 606 extern int namei(const char * pathname, struct inode ** res_inode);
 607 extern int lnamei(const char * pathname, struct inode ** res_inode);
 608 extern int permission(struct inode * inode,int mask);
 609 extern int get_write_access(struct inode *inode);
 610 extern void put_write_access(struct inode *inode);
 611 extern int open_namei(const char * pathname, int flag, int mode,
 612         struct inode ** res_inode, struct inode * base);
 613 extern int do_mknod(const char * filename, int mode, dev_t dev);
 614 extern int do_pipe(int *);
 615 extern void iput(struct inode * inode);
 616 extern struct inode * __iget(struct super_block * sb,int nr,int crsmnt);
 617 extern struct inode * get_empty_inode(void);
 618 extern void insert_inode_hash(struct inode *);
 619 extern void clear_inode(struct inode *);
 620 extern struct inode * get_pipe_inode(void);
 621 extern struct file * get_empty_filp(void);
 622 extern int close_fp(struct file *filp);
 623 extern struct buffer_head * get_hash_table(kdev_t dev, int block, int size);
 624 extern struct buffer_head * getblk(kdev_t dev, int block, int size);
 625 extern void ll_rw_block(int rw, int nr, struct buffer_head * bh[]);
 626 extern void ll_rw_page(int rw, kdev_t dev, unsigned long nr, char * buffer);
 627 extern void ll_rw_swap_file(int rw, kdev_t dev, unsigned int *b, int nb, char *buffer);
 628 extern int is_read_only(kdev_t dev);
 629 extern void __brelse(struct buffer_head *buf);
 630 extern inline void brelse(struct buffer_head *buf)
     /*  */
 631 {
 632         if (buf)
 633                 __brelse(buf);
 634 }
 635 extern void __bforget(struct buffer_head *buf);
 636 extern inline void bforget(struct buffer_head *buf)
     /*  */
 637 {
 638         if (buf)
 639                 __bforget(buf);
 640 }
 641 extern void set_blocksize(kdev_t dev, int size);
 642 extern struct buffer_head * bread(kdev_t dev, int block, int size);
 643 extern struct buffer_head * breada(kdev_t dev,int block, int size, 
 644                                    unsigned int pos, unsigned int filesize);
 645 
 646 extern int generic_readpage(struct inode *, struct page *);
 647 extern int generic_file_read(struct inode *, struct file *, char *, int);
 648 extern int generic_file_mmap(struct inode *, struct file *, struct vm_area_struct *);
 649 extern int brw_page(int, unsigned long, kdev_t, int [], int, int);
 650 
 651 extern void put_super(kdev_t dev);
 652 unsigned long generate_cluster(kdev_t dev, int b[], int size);
 653 extern kdev_t ROOT_DEV;
 654 
 655 extern void show_buffers(void);
 656 extern void mount_root(void);
 657 
 658 #ifdef CONFIG_BLK_DEV_INITRD
 659 extern kdev_t real_root_dev;
 660 extern int change_root(kdev_t new_root_dev,const char *put_old);
 661 #endif
 662 
 663 extern int char_read(struct inode *, struct file *, char *, int);
 664 extern int block_read(struct inode *, struct file *, char *, int);
 665 extern int read_ahead[];
 666 
 667 extern int char_write(struct inode *, struct file *, const char *, int);
 668 extern int block_write(struct inode *, struct file *, const char *, int);
 669 
 670 extern int block_fsync(struct inode *, struct file *);
 671 extern int file_fsync(struct inode *, struct file *);
 672 
 673 extern void dcache_add(struct inode *, const char *, int, unsigned long);
 674 extern int dcache_lookup(struct inode *, const char *, int, unsigned long *);
 675 
 676 extern int inode_change_ok(struct inode *, struct iattr *);
 677 extern void inode_setattr(struct inode *, struct iattr *);
 678 
 679 extern inline struct inode * iget(struct super_block * sb,int nr)
     /*  */
 680 {
 681         return __iget(sb, nr, 1);
 682 }
 683 
 684 /* kludge to get SCSI modules working */
 685 #include <linux/minix_fs.h>
 686 #include <linux/minix_fs_sb.h>
 687 
 688 #endif /* __KERNEL__ */
 689 
 690 #endif

/* */