root/include/linux/fs.h

/* */

INCLUDED FROM

DEFINITIONS

1. mark_buffer_clean
2. mark_buffer_dirty
3. 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 
  16 /*
  17  * It's silly to have NR_OPEN bigger than NR_FILE, but I'll fix
  18  * that later. Anyway, now the file code is no longer dependent
  19  * on bitmaps in unsigned longs, but uses the new fd_set structure..
  20  *
  21  * Some programs (notably those using select()) may have to be 
  22  * recompiled to take full advantage of the new limits..
  23  */
  24 #undef NR_OPEN
  25 #define NR_OPEN 256
  26 
  27 #define NR_INODE 2048   /* this should be bigger than NR_FILE */
  28 #define NR_FILE 1024    /* this can well be larger on a larger system */
  29 #define NR_SUPER 32
  30 #define NR_IHASH 131
  31 #define BLOCK_SIZE 1024
  32 #define BLOCK_SIZE_BITS 10
  33 
  34 #define MAY_EXEC 1
  35 #define MAY_WRITE 2
  36 #define MAY_READ 4
  37 
  38 #define READ 0
  39 #define WRITE 1
  40 #define READA 2         /* read-ahead - don't pause */
  41 #define WRITEA 3        /* "write-ahead" - silly, but somewhat useful */
  42 
  43 extern void buffer_init(void);
  44 extern unsigned long inode_init(unsigned long start, unsigned long end);
  45 extern unsigned long file_table_init(unsigned long start, unsigned long end);
  46 extern unsigned long name_cache_init(unsigned long start, unsigned long end);
  47 
  48 #define MAJOR(a) (int)((unsigned short)(a) >> 8)
  49 #define MINOR(a) (int)((unsigned short)(a) & 0xFF)
  50 #define MKDEV(a,b) ((int)((((a) & 0xff) << 8) | ((b) & 0xff)))
  51 #define NODEV MKDEV(0,0)
  52 
  53 #ifndef NULL
  54 #define NULL ((void *) 0)
  55 #endif
  56 
  57 #define NIL_FILP        ((struct file *)0)
  58 #define SEL_IN          1
  59 #define SEL_OUT         2
  60 #define SEL_EX          4
  61 
  62 /*
  63  * These are the fs-independent mount-flags: up to 16 flags are supported
  64  */
  65 #define MS_RDONLY        1 /* mount read-only */
  66 #define MS_NOSUID        2 /* ignore suid and sgid bits */
  67 #define MS_NODEV         4 /* disallow access to device special files */
  68 #define MS_NOEXEC        8 /* disallow program execution */
  69 #define MS_SYNCHRONOUS  16 /* writes are synced at once */
  70 #define MS_REMOUNT      32 /* alter flags of a mounted FS */
  71 
  72 #define S_APPEND    256 /* append-only file */
  73 #define S_IMMUTABLE 512 /* immutable file */
  74 
  75 /*
  76  * Flags that can be altered by MS_REMOUNT
  77  */
  78 #define MS_RMT_MASK (MS_RDONLY)
  79 
  80 /*
  81  * Magic mount flag number. Has to be or-ed to the flag values.
  82  */
  83 #define MS_MGC_VAL 0xC0ED0000 /* magic flag number to indicate "new" flags */
  84 #define MS_MGC_MSK 0xffff0000 /* magic flag number mask */
  85 
  86 /*
  87  * Note that read-only etc flags are inode-specific: setting some file-system
  88  * flags just means all the inodes inherit those flags by default. It might be
  89  * possible to override it selectively if you really wanted to with some
  90  * ioctl() that is not currently implemented.
  91  *
  92  * Exception: MS_RDONLY is always applied to the entire file system.
  93  */
  94 #define IS_RDONLY(inode) (((inode)->i_sb) && ((inode)->i_sb->s_flags & MS_RDONLY))
  95 #define IS_NOSUID(inode) ((inode)->i_flags & MS_NOSUID)
  96 #define IS_NODEV(inode) ((inode)->i_flags & MS_NODEV)
  97 #define IS_NOEXEC(inode) ((inode)->i_flags & MS_NOEXEC)
  98 #define IS_SYNC(inode) ((inode)->i_flags & MS_SYNCHRONOUS)
  99 
 100 #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
 101 #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
 102 
 103 /* the read-only stuff doesn't really belong here, but any other place is
 104    probably as bad and I don't want to create yet another include file. */
 105 
 106 #define BLKROSET 4701 /* set device read-only (0 = read-write) */
 107 #define BLKROGET 4702 /* get read-only status (0 = read_write) */
 108 #define BLKRRPART 4703 /* re-read partition table */
 109 #define BLKGETSIZE 4704 /* return device size */
 110 #define BLKFLSBUF 4705 /* flush buffer cache */
 111 #define BLKRASET 4706 /* Set read ahead for block device */
 112 #define BLKRAGET 4707 /* get current read ahead setting */
 113 
 114 /* These are a few other constants  only used by scsi  devices */
 115 
 116 #define SCSI_IOCTL_GET_IDLUN 0x5382
 117 
 118 /* Used to turn on and off tagged queuing for scsi devices */
 119 
 120 #define SCSI_IOCTL_TAGGED_ENABLE 0x5383
 121 #define SCSI_IOCTL_TAGGED_DISABLE 0x5384
 122 
 123 
 124 #define BMAP_IOCTL 1    /* obsolete - kept for compatibility */
 125 #define FIBMAP     1    /* bmap access */
 126 #define FIGETBSZ   2    /* get the block size used for bmap */
 127 
 128 typedef char buffer_block[BLOCK_SIZE];
 129 
 130 struct buffer_head {
 131         char * b_data;                  /* pointer to data block (1024 bytes) */
 132         unsigned long b_size;           /* block size */
 133         unsigned long b_blocknr;        /* block number */
 134         dev_t b_dev;                    /* device (0 = free) */
 135         unsigned short b_count;         /* users using this block */
 136         unsigned char b_uptodate;
 137         unsigned char b_dirt;           /* 0-clean,1-dirty */
 138         unsigned char b_lock;           /* 0 - ok, 1 -locked */
 139         unsigned char b_req;            /* 0 if the buffer has been invalidated */
 140         unsigned char b_list;           /* List that this buffer appears */
 141         unsigned char b_retain;         /* Expected number of times this will
 142                                            be used.  Put on freelist when 0 */
 143         unsigned long b_flushtime;      /* Time when this (dirty) buffer should be written */
 144         unsigned long b_lru_time;       /* Time when this buffer was last used. */
 145         struct wait_queue * b_wait;
 146         struct buffer_head * b_prev;            /* doubly linked list of hash-queue */
 147         struct buffer_head * b_next;
 148         struct buffer_head * b_prev_free;       /* doubly linked list of buffers */
 149         struct buffer_head * b_next_free;
 150         struct buffer_head * b_this_page;       /* circular list of buffers in one page */
 151         struct buffer_head * b_reqnext;         /* request queue */
 152 };
 153 
 154 #include <linux/pipe_fs_i.h>
 155 #include <linux/minix_fs_i.h>
 156 #include <linux/ext_fs_i.h>
 157 #include <linux/ext2_fs_i.h>
 158 #include <linux/hpfs_fs_i.h>
 159 #include <linux/msdos_fs_i.h>
 160 #include <linux/umsdos_fs_i.h>
 161 #include <linux/iso_fs_i.h>
 162 #include <linux/nfs_fs_i.h>
 163 #include <linux/xia_fs_i.h>
 164 #include <linux/sysv_fs_i.h>
 165 
 166 #ifdef __KERNEL__
 167 
 168 /*
 169  * Attribute flags.  These should be or-ed together to figure out what
 170  * has been changed!
 171  */
 172 #define ATTR_MODE       1
 173 #define ATTR_UID        2
 174 #define ATTR_GID        4
 175 #define ATTR_SIZE       8
 176 #define ATTR_ATIME      16
 177 #define ATTR_MTIME      32
 178 #define ATTR_CTIME      64
 179 #define ATTR_ATIME_SET  128
 180 #define ATTR_MTIME_SET  256
 181 
 182 /*
 183  * This is the Inode Attributes structure, used for notify_change().  It
 184  * uses the above definitions as flags, to know which values have changed.
 185  * Also, in this manner, a Filesystem can look at only the values it cares
 186  * about.  Basically, these are the attributes that the VFS layer can
 187  * request to change from the FS layer.
 188  *
 189  * Derek Atkins <warlord@MIT.EDU> 94-10-20
 190  */
 191 struct iattr {
 192         unsigned int    ia_valid;
 193         umode_t         ia_mode;
 194         uid_t           ia_uid;
 195         gid_t           ia_gid;
 196         off_t           ia_size;
 197         time_t          ia_atime;
 198         time_t          ia_mtime;
 199         time_t          ia_ctime;
 200 };
 201 
 202 struct inode {
 203         dev_t           i_dev;
 204         unsigned long   i_ino;
 205         umode_t         i_mode;
 206         nlink_t         i_nlink;
 207         uid_t           i_uid;
 208         gid_t           i_gid;
 209         dev_t           i_rdev;
 210         off_t           i_size;
 211         time_t          i_atime;
 212         time_t          i_mtime;
 213         time_t          i_ctime;
 214         unsigned long   i_blksize;
 215         unsigned long   i_blocks;
 216         unsigned long   i_version;
 217         struct semaphore i_sem;
 218         struct inode_operations * i_op;
 219         struct super_block * i_sb;
 220         struct wait_queue * i_wait;
 221         struct file_lock * i_flock;
 222         struct vm_area_struct * i_mmap;
 223         struct inode * i_next, * i_prev;
 224         struct inode * i_hash_next, * i_hash_prev;
 225         struct inode * i_bound_to, * i_bound_by;
 226         struct inode * i_mount;
 227         unsigned short i_count;
 228         unsigned short i_wcount;
 229         unsigned short i_flags;
 230         unsigned char i_lock;
 231         unsigned char i_dirt;
 232         unsigned char i_pipe;
 233         unsigned char i_sock;
 234         unsigned char i_seek;
 235         unsigned char i_update;
 236         union {
 237                 struct pipe_inode_info pipe_i;
 238                 struct minix_inode_info minix_i;
 239                 struct ext_inode_info ext_i;
 240                 struct ext2_inode_info ext2_i;
 241                 struct hpfs_inode_info hpfs_i;
 242                 struct msdos_inode_info msdos_i;
 243                 struct umsdos_inode_info umsdos_i;
 244                 struct iso_inode_info isofs_i;
 245                 struct nfs_inode_info nfs_i;
 246                 struct xiafs_inode_info xiafs_i;
 247                 struct sysv_inode_info sysv_i;
 248                 struct socket socket_i;
 249                 void * generic_ip;
 250         } u;
 251 };
 252 
 253 struct file {
 254         mode_t f_mode;
 255         loff_t f_pos;
 256         unsigned short f_flags;
 257         unsigned short f_count;
 258         off_t f_reada;
 259         struct file *f_next, *f_prev;
 260         int f_owner;            /* pid or -pgrp where SIGIO should be sent */
 261         struct inode * f_inode;
 262         struct file_operations * f_op;
 263         unsigned long f_version;
 264         void *private_data;     /* needed for tty driver, and maybe others */
 265 };
 266 
 267 struct file_lock {
 268         struct file_lock *fl_next;      /* singly linked list for this inode  */
 269         struct file_lock *fl_nextlink;  /* doubly linked list of all locks */
 270         struct file_lock *fl_prevlink;  /* used to simplify lock removal */
 271         struct file_lock *fl_block;
 272         struct task_struct *fl_owner;
 273         struct wait_queue *fl_wait;
 274         struct file *fl_file;
 275         char fl_flags;
 276         char fl_type;
 277         off_t fl_start;
 278         off_t fl_end;
 279 };
 280 
 281 struct fasync_struct {
 282         int    magic;
 283         struct fasync_struct    *fa_next; /* singly linked list */
 284         struct file             *fa_file;
 285 };
 286 
 287 #define FASYNC_MAGIC 0x4601
 288 
 289 #include <linux/minix_fs_sb.h>
 290 #include <linux/ext_fs_sb.h>
 291 #include <linux/ext2_fs_sb.h>
 292 #include <linux/hpfs_fs_sb.h>
 293 #include <linux/msdos_fs_sb.h>
 294 #include <linux/iso_fs_sb.h>
 295 #include <linux/nfs_fs_sb.h>
 296 #include <linux/xia_fs_sb.h>
 297 #include <linux/sysv_fs_sb.h>
 298 
 299 struct super_block {
 300         dev_t s_dev;
 301         unsigned long s_blocksize;
 302         unsigned char s_blocksize_bits;
 303         unsigned char s_lock;
 304         unsigned char s_rd_only;
 305         unsigned char s_dirt;
 306         struct file_system_type *s_type;
 307         struct super_operations *s_op;
 308         unsigned long s_flags;
 309         unsigned long s_magic;
 310         unsigned long s_time;
 311         struct inode * s_covered;
 312         struct inode * s_mounted;
 313         struct wait_queue * s_wait;
 314         union {
 315                 struct minix_sb_info minix_sb;
 316                 struct ext_sb_info ext_sb;
 317                 struct ext2_sb_info ext2_sb;
 318                 struct hpfs_sb_info hpfs_sb;
 319                 struct msdos_sb_info msdos_sb;
 320                 struct isofs_sb_info isofs_sb;
 321                 struct nfs_sb_info nfs_sb;
 322                 struct xiafs_sb_info xiafs_sb;
 323                 struct sysv_sb_info sysv_sb;
 324                 void *generic_sbp;
 325         } u;
 326 };
 327 
 328 /*
 329  * This is the "filldir" function type, used by readdir() to let
 330  * the kernel specify what kind of dirent layout it wants to have.
 331  * This allows the kernel to read directories into kernel space or
 332  * to have different dirent layouts depending on the binary type.
 333  */
 334 typedef int (*filldir_t)(void *, const char *, int, off_t, ino_t);
 335         
 336 struct file_operations {
 337         int (*lseek) (struct inode *, struct file *, off_t, int);
 338         int (*read) (struct inode *, struct file *, char *, int);
 339         int (*write) (struct inode *, struct file *, char *, int);
 340         int (*readdir) (struct inode *, struct file *, void *, filldir_t);
 341         int (*select) (struct inode *, struct file *, int, select_table *);
 342         int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
 343         int (*mmap) (struct inode *, struct file *, struct vm_area_struct *);
 344         int (*open) (struct inode *, struct file *);
 345         void (*release) (struct inode *, struct file *);
 346         int (*fsync) (struct inode *, struct file *);
 347         int (*fasync) (struct inode *, struct file *, int);
 348         int (*check_media_change) (dev_t dev);
 349         int (*revalidate) (dev_t dev);
 350 };
 351 
 352 struct inode_operations {
 353         struct file_operations * default_file_ops;
 354         int (*create) (struct inode *,const char *,int,int,struct inode **);
 355         int (*lookup) (struct inode *,const char *,int,struct inode **);
 356         int (*link) (struct inode *,struct inode *,const char *,int);
 357         int (*unlink) (struct inode *,const char *,int);
 358         int (*symlink) (struct inode *,const char *,int,const char *);
 359         int (*mkdir) (struct inode *,const char *,int,int);
 360         int (*rmdir) (struct inode *,const char *,int);
 361         int (*mknod) (struct inode *,const char *,int,int,int);
 362         int (*rename) (struct inode *,const char *,int,struct inode *,const char *,int);
 363         int (*readlink) (struct inode *,char *,int);
 364         int (*follow_link) (struct inode *,struct inode *,int,int,struct inode **);
 365         int (*bmap) (struct inode *,int);
 366         void (*truncate) (struct inode *);
 367         int (*permission) (struct inode *, int);
 368         int (*smap) (struct inode *,int);
 369 };
 370 
 371 struct super_operations {
 372         void (*read_inode) (struct inode *);
 373         int (*notify_change) (struct inode *, struct iattr *);
 374         void (*write_inode) (struct inode *);
 375         void (*put_inode) (struct inode *);
 376         void (*put_super) (struct super_block *);
 377         void (*write_super) (struct super_block *);
 378         void (*statfs) (struct super_block *, struct statfs *, int);
 379         int (*remount_fs) (struct super_block *, int *, char *);
 380 };
 381 
 382 struct file_system_type {
 383         struct super_block *(*read_super) (struct super_block *, void *, int);
 384         char *name;
 385         int requires_dev;
 386         struct file_system_type * next;
 387 };
 388 
 389 extern int register_filesystem(struct file_system_type *);
 390 extern int unregister_filesystem(struct file_system_type *);
 391 
 392 asmlinkage int sys_open(const char *, int, int);
 393 asmlinkage int sys_close(unsigned int);         /* yes, it's really unsigned */
 394 
 395 extern void kill_fasync(struct fasync_struct *fa, int sig);
 396 
 397 extern int getname(const char * filename, char **result);
 398 extern void putname(char * name);
 399 
 400 extern int register_blkdev(unsigned int, const char *, struct file_operations *);
 401 extern int unregister_blkdev(unsigned int major, const char * name);
 402 extern int blkdev_open(struct inode * inode, struct file * filp);
 403 extern struct file_operations def_blk_fops;
 404 extern struct inode_operations blkdev_inode_operations;
 405 
 406 extern int register_chrdev(unsigned int, const char *, struct file_operations *);
 407 extern int unregister_chrdev(unsigned int major, const char * name);
 408 extern int chrdev_open(struct inode * inode, struct file * filp);
 409 extern struct file_operations def_chr_fops;
 410 extern struct inode_operations chrdev_inode_operations;
 411 
 412 extern void init_fifo(struct inode * inode);
 413 
 414 extern struct file_operations connecting_fifo_fops;
 415 extern struct file_operations read_fifo_fops;
 416 extern struct file_operations write_fifo_fops;
 417 extern struct file_operations rdwr_fifo_fops;
 418 extern struct file_operations read_pipe_fops;
 419 extern struct file_operations write_pipe_fops;
 420 extern struct file_operations rdwr_pipe_fops;
 421 
 422 extern struct file_system_type *get_fs_type(char *name);
 423 
 424 extern int fs_may_mount(dev_t dev);
 425 extern int fs_may_umount(dev_t dev, struct inode * mount_root);
 426 extern int fs_may_remount_ro(dev_t dev);
 427 
 428 extern struct file *first_file;
 429 extern int nr_files;
 430 extern struct super_block super_blocks[NR_SUPER];
 431 
 432 extern int shrink_buffers(unsigned int priority, unsigned long limit);
 433 extern void refile_buffer(struct buffer_head * buf);
 434 extern void set_writetime(struct buffer_head * buf, int flag);
 435 extern void refill_freelist(int size);
 436 
 437 extern struct buffer_head ** buffer_pages;
 438 extern int nr_buffers;
 439 extern int buffermem;
 440 extern int nr_buffer_heads;
 441 
 442 #define BUF_CLEAN 0
 443 #define BUF_UNSHARED 1 /* Buffers that were shared but are not any more */
 444 #define BUF_LOCKED 2   /* Buffers scheduled for write */
 445 #define BUF_LOCKED1 3  /* Supers, inodes */
 446 #define BUF_DIRTY 4    /* Dirty buffers, not yet scheduled for write */
 447 #define BUF_SHARED 5   /* Buffers shared */
 448 #define NR_LIST 6
 449 
 450 extern inline void mark_buffer_clean(struct buffer_head * bh)
     /*  */
 451 {
 452   if(bh->b_dirt) {
 453     bh->b_dirt = 0;
 454     if(bh->b_list == BUF_DIRTY) refile_buffer(bh);
 455   }
 456 }
 457 
 458 extern inline void mark_buffer_dirty(struct buffer_head * bh, int flag)
     /*  */
 459 {
 460   if(!bh->b_dirt) {
 461     bh->b_dirt = 1;
 462     set_writetime(bh, flag);
 463     if(bh->b_list != BUF_DIRTY) refile_buffer(bh);
 464   }
 465 }
 466 
 467 
 468 extern int check_disk_change(dev_t dev);
 469 extern void invalidate_inodes(dev_t dev);
 470 extern void invalidate_buffers(dev_t dev);
 471 extern int floppy_is_wp(int minor);
 472 extern void sync_inodes(dev_t dev);
 473 extern void sync_dev(dev_t dev);
 474 extern int fsync_dev(dev_t dev);
 475 extern void sync_supers(dev_t dev);
 476 extern int bmap(struct inode * inode,int block);
 477 extern int notify_change(struct inode *, struct iattr *);
 478 extern int namei(const char * pathname, struct inode ** res_inode);
 479 extern int lnamei(const char * pathname, struct inode ** res_inode);
 480 extern int permission(struct inode * inode,int mask);
 481 extern int get_write_access(struct inode * inode);
 482 extern void put_write_access(struct inode * inode);
 483 extern int open_namei(const char * pathname, int flag, int mode,
 484         struct inode ** res_inode, struct inode * base);
 485 extern int do_mknod(const char * filename, int mode, dev_t dev);
 486 extern int do_pipe(int *);
 487 extern void iput(struct inode * inode);
 488 extern struct inode * __iget(struct super_block * sb,int nr,int crsmnt);
 489 extern struct inode * get_empty_inode(void);
 490 extern void insert_inode_hash(struct inode *);
 491 extern void clear_inode(struct inode *);
 492 extern struct inode * get_pipe_inode(void);
 493 extern struct file * get_empty_filp(void);
 494 extern struct buffer_head * get_hash_table(dev_t dev, int block, int size);
 495 extern struct buffer_head * getblk(dev_t dev, int block, int size);
 496 extern void ll_rw_block(int rw, int nr, struct buffer_head * bh[]);
 497 extern void ll_rw_page(int rw, int dev, unsigned long nr, char * buffer);
 498 extern void ll_rw_swap_file(int rw, int dev, unsigned int *b, int nb, char *buffer);
 499 extern int is_read_only(int dev);
 500 extern void brelse(struct buffer_head * buf);
 501 extern void set_blocksize(dev_t dev, int size);
 502 extern struct buffer_head * bread(dev_t dev, int block, int size);
 503 extern unsigned long bread_page(unsigned long addr,dev_t dev,int b[],int size,int no_share);
 504 extern void bwrite_page(unsigned long addr,dev_t dev,int b[],int size);
 505 extern struct buffer_head * breada(dev_t dev,int block, int size, 
 506                                    unsigned int pos, unsigned int filesize);
 507 extern void put_super(dev_t dev);
 508 unsigned long generate_cluster(dev_t dev, int b[], int size);
 509 extern dev_t ROOT_DEV;
 510 
 511 extern void show_buffers(void);
 512 extern void mount_root(void);
 513 
 514 extern int char_read(struct inode *, struct file *, char *, int);
 515 extern int block_read(struct inode *, struct file *, char *, int);
 516 extern int read_ahead[];
 517 
 518 extern int char_write(struct inode *, struct file *, char *, int);
 519 extern int block_write(struct inode *, struct file *, char *, int);
 520 
 521 extern int generic_mmap(struct inode *, struct file *, struct vm_area_struct *);
 522 
 523 extern int block_fsync(struct inode *, struct file *);
 524 extern int file_fsync(struct inode *, struct file *);
 525 
 526 extern void dcache_add(struct inode *, const char *, int, unsigned long);
 527 extern int dcache_lookup(struct inode *, const char *, int, unsigned long *);
 528 
 529 extern int inode_change_ok(struct inode *, struct iattr *);
 530 extern void inode_setattr(struct inode *, struct iattr *);
 531 
 532 extern inline struct inode * iget(struct super_block * sb,int nr)
     /*  */
 533 {
 534         return __iget(sb,nr,1);
 535 }
 536 
 537 #endif /* __KERNEL__ */
 538 
 539 #endif

/* */