root/include/linux/fs.h

/* */

INCLUDED FROM

   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/dirent.h>
  14 #include <linux/vfs.h>
  15 #include <linux/net.h>
  16 
  17 /*
  18  * It's silly to have NR_OPEN bigger than NR_FILE, but I'll fix
  19  * that later. Anyway, now the file code is no longer dependent
  20  * on bitmaps in unsigned longs, but uses the new fd_set structure..
  21  *
  22  * Some programs (notably those using select()) may have to be 
  23  * recompiled to take full advantage of the new limits..
  24  */
  25 #undef NR_OPEN
  26 #define NR_OPEN 256
  27 
  28 #define NR_INODE 2048   /* this should be bigger than NR_FILE */
  29 #define NR_FILE 1024    /* this can well be larger on a larger system */
  30 #define NR_SUPER 32
  31 #define NR_HASH 997
  32 #define NR_IHASH 131
  33 #define NR_FILE_LOCKS 64
  34 #define BLOCK_SIZE 1024
  35 #define BLOCK_SIZE_BITS 10
  36 
  37 #define MAY_EXEC 1
  38 #define MAY_WRITE 2
  39 #define MAY_READ 4
  40 
  41 #define READ 0
  42 #define WRITE 1
  43 #define READA 2         /* read-ahead - don't pause */
  44 #define WRITEA 3        /* "write-ahead" - silly, but somewhat useful */
  45 
  46 extern void buffer_init(void);
  47 extern unsigned long inode_init(unsigned long start, unsigned long end);
  48 extern unsigned long file_table_init(unsigned long start, unsigned long end);
  49 
  50 #define MAJOR(a) (int)((unsigned short)(a) >> 8)
  51 #define MINOR(a) (int)((unsigned short)(a) & 0xFF)
  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_SYNC     16 /* writes are synced at once */
  70 #define MS_REMOUNT  32 /* alter flags of a mounted FS */
  71 
  72 /*
  73  * Flags that can be altered by MS_REMOUNT
  74  */
  75 #define MS_RMT_MASK (MS_RDONLY)
  76 
  77 /*
  78  * Magic mount flag number. Has to be or-ed to the flag values.
  79  */
  80 #define MS_MGC_VAL 0xC0ED0000 /* magic flag number to indicate "new" flags */
  81 #define MS_MGC_MSK 0xffff0000 /* magic flag number mask */
  82 
  83 /*
  84  * Note that read-only etc flags are inode-specific: setting some file-system
  85  * flags just means all the inodes inherit those flags by default. It might be
  86  * possible to overrride it sevelctively if you really wanted to with some
  87  * ioctl() that is not currently implemented.
  88  *
  89  * Exception: MS_RDONLY is always applied to the entire file system.
  90  */
  91 #define IS_RDONLY(inode) (((inode)->i_sb) && ((inode)->i_sb->s_flags & MS_RDONLY))
  92 #define IS_NOSUID(inode) ((inode)->i_flags & MS_NOSUID)
  93 #define IS_NODEV(inode) ((inode)->i_flags & MS_NODEV)
  94 #define IS_NOEXEC(inode) ((inode)->i_flags & MS_NOEXEC)
  95 #define IS_SYNC(inode) ((inode)->i_flags & MS_SYNC)
  96 
  97 /* the read-only stuff doesn't really belong here, but any other place is
  98    probably as bad and I don't want to create yet another include file. */
  99 
 100 #define BLKROSET 4701 /* set device read-only (0 = read-write) */
 101 #define BLKROGET 4702 /* get read-only status (0 = read_write) */
 102 #define BLKRRPART 4703 /* re-read partition table */
 103 #define BLKGETSIZE 4704 /* return device size */
 104 #define BLKFLSBUF 4705 /* flush buffer cache */
 105 
 106 /* These are a few other constants  only used by scsi  devices */
 107 
 108 #define SCSI_IOCTL_GET_IDLUN 0x5382
 109 
 110 /* Used to turn on and off tagged queueing for scsi devices */
 111 
 112 #define SCSI_IOCTL_TAGGED_ENABLE 0x5383
 113 #define SCSI_IOCTL_TAGGED_DISABLE 0x5384
 114 
 115 
 116 #define BMAP_IOCTL 1    /* obsolete - kept for compatibility */
 117 #define FIBMAP     1    /* bmap access */
 118 #define FIGETBSZ   2    /* get the block size used for bmap */
 119 
 120 /* these flags tell notify_change what is being changed */
 121 
 122 #define NOTIFY_SIZE     1
 123 #define NOTIFY_MODE     2
 124 #define NOTIFY_TIME     4
 125 #define NOTIFY_UIDGID   8
 126 
 127 typedef char buffer_block[BLOCK_SIZE];
 128 
 129 struct buffer_head {
 130         char * b_data;                  /* pointer to data block (1024 bytes) */
 131         unsigned long b_size;           /* block size */
 132         unsigned long b_blocknr;        /* block number */
 133         dev_t b_dev;                    /* device (0 = free) */
 134         unsigned short b_count;         /* users using this block */
 135         unsigned char b_uptodate;
 136         unsigned char b_dirt;           /* 0-clean,1-dirty */
 137         unsigned char b_lock;           /* 0 - ok, 1 -locked */
 138         unsigned char b_req;            /* 0 if the buffer has been invalidated */
 139         struct wait_queue * b_wait;
 140         struct buffer_head * b_prev;            /* doubly linked list of hash-queue */
 141         struct buffer_head * b_next;
 142         struct buffer_head * b_prev_free;       /* doubly linked list of buffers */
 143         struct buffer_head * b_next_free;
 144         struct buffer_head * b_this_page;       /* circular list of buffers in one page */
 145         struct buffer_head * b_reqnext;         /* request queue */
 146 };
 147 
 148 #include <linux/pipe_fs_i.h>
 149 #include <linux/minix_fs_i.h>
 150 #include <linux/ext_fs_i.h>
 151 #include <linux/ext2_fs_i.h>
 152 #include <linux/hpfs_fs_i.h>
 153 #include <linux/msdos_fs_i.h>
 154 #include <linux/iso_fs_i.h>
 155 #include <linux/nfs_fs_i.h>
 156 #include <linux/xia_fs_i.h>
 157 
 158 struct inode {
 159         dev_t           i_dev;
 160         unsigned long   i_ino;
 161         umode_t         i_mode;
 162         nlink_t         i_nlink;
 163         uid_t           i_uid;
 164         gid_t           i_gid;
 165         dev_t           i_rdev;
 166         off_t           i_size;
 167         time_t          i_atime;
 168         time_t          i_mtime;
 169         time_t          i_ctime;
 170         unsigned long   i_blksize;
 171         unsigned long   i_blocks;
 172         struct inode_operations * i_op;
 173         struct super_block * i_sb;
 174         struct wait_queue * i_wait;
 175         struct file_lock * i_flock;
 176         struct vm_area_struct * i_mmap;
 177         struct inode * i_next, * i_prev;
 178         struct inode * i_hash_next, * i_hash_prev;
 179         struct inode * i_bound_to, * i_bound_by;
 180         struct inode * i_mount;
 181         struct socket * i_socket;
 182         unsigned short i_count;
 183         unsigned short i_flags;
 184         unsigned char i_lock;
 185         unsigned char i_dirt;
 186         unsigned char i_pipe;
 187         unsigned char i_seek;
 188         unsigned char i_update;
 189         union {
 190                 struct pipe_inode_info pipe_i;
 191                 struct minix_inode_info minix_i;
 192                 struct ext_inode_info ext_i;
 193                 struct ext2_inode_info ext2_i;
 194                 struct hpfs_inode_info hpfs_i;
 195                 struct msdos_inode_info msdos_i;
 196                 struct iso_inode_info isofs_i;
 197                 struct nfs_inode_info nfs_i;
 198                 struct xiafs_inode_info xiafs_i;
 199         } u;
 200 };
 201 
 202 struct file {
 203         mode_t f_mode;
 204         dev_t f_rdev;                   /* needed for /dev/tty */
 205         off_t f_pos;
 206         unsigned short f_flags;
 207         unsigned short f_count;
 208         unsigned short f_reada;
 209         struct file *f_next, *f_prev;
 210         struct inode * f_inode;
 211         struct file_operations * f_op;
 212 };
 213 
 214 struct file_lock {
 215         struct file_lock *fl_next;      /* singly linked list */
 216         struct task_struct *fl_owner;   /* NULL if on free list, for sanity checks */
 217         unsigned int fl_fd;             /* File descriptor for this lock */
 218         struct wait_queue *fl_wait;
 219         char fl_type;
 220         char fl_whence;
 221         off_t fl_start;
 222         off_t fl_end;
 223 };
 224 
 225 #include <linux/minix_fs_sb.h>
 226 #include <linux/ext_fs_sb.h>
 227 #include <linux/ext2_fs_sb.h>
 228 #include <linux/hpfs_fs_sb.h>
 229 #include <linux/msdos_fs_sb.h>
 230 #include <linux/iso_fs_sb.h>
 231 #include <linux/nfs_fs_sb.h>
 232 #include <linux/xia_fs_sb.h>
 233 
 234 struct super_block {
 235         dev_t s_dev;
 236         unsigned long s_blocksize;
 237         unsigned char s_blocksize_bits;
 238         unsigned char s_lock;
 239         unsigned char s_rd_only;
 240         unsigned char s_dirt;
 241         struct super_operations *s_op;
 242         unsigned long s_flags;
 243         unsigned long s_magic;
 244         unsigned long s_time;
 245         struct inode * s_covered;
 246         struct inode * s_mounted;
 247         struct wait_queue * s_wait;
 248         union {
 249                 struct minix_sb_info minix_sb;
 250                 struct ext_sb_info ext_sb;
 251                 struct ext2_sb_info ext2_sb;
 252                 struct hpfs_sb_info hpfs_sb;
 253                 struct msdos_sb_info msdos_sb;
 254                 struct isofs_sb_info isofs_sb;
 255                 struct nfs_sb_info nfs_sb;
 256                 struct xiafs_sb_info xiafs_sb;
 257         } u;
 258 };
 259 
 260 struct file_operations {
 261         int (*lseek) (struct inode *, struct file *, off_t, int);
 262         int (*read) (struct inode *, struct file *, char *, int);
 263         int (*write) (struct inode *, struct file *, char *, int);
 264         int (*readdir) (struct inode *, struct file *, struct dirent *, int);
 265         int (*select) (struct inode *, struct file *, int, select_table *);
 266         int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
 267         int (*mmap) (struct inode *, struct file *, unsigned long, size_t, int, unsigned long);
 268         int (*open) (struct inode *, struct file *);
 269         void (*release) (struct inode *, struct file *);
 270         int (*fsync) (struct inode *, struct file *);
 271 };
 272 
 273 struct inode_operations {
 274         struct file_operations * default_file_ops;
 275         int (*create) (struct inode *,const char *,int,int,struct inode **);
 276         int (*lookup) (struct inode *,const char *,int,struct inode **);
 277         int (*link) (struct inode *,struct inode *,const char *,int);
 278         int (*unlink) (struct inode *,const char *,int);
 279         int (*symlink) (struct inode *,const char *,int,const char *);
 280         int (*mkdir) (struct inode *,const char *,int,int);
 281         int (*rmdir) (struct inode *,const char *,int);
 282         int (*mknod) (struct inode *,const char *,int,int,int);
 283         int (*rename) (struct inode *,const char *,int,struct inode *,const char *,int);
 284         int (*readlink) (struct inode *,char *,int);
 285         int (*follow_link) (struct inode *,struct inode *,int,int,struct inode **);
 286         int (*bmap) (struct inode *,int);
 287         void (*truncate) (struct inode *);
 288         int (*permission) (struct inode *, int);
 289 };
 290 
 291 struct super_operations {
 292         void (*read_inode) (struct inode *);
 293         int (*notify_change) (int flags, struct inode *);
 294         void (*write_inode) (struct inode *);
 295         void (*put_inode) (struct inode *);
 296         void (*put_super) (struct super_block *);
 297         void (*write_super) (struct super_block *);
 298         void (*statfs) (struct super_block *, struct statfs *);
 299         int (*remount_fs) (struct super_block *, int *);
 300 };
 301 
 302 struct file_system_type {
 303         struct super_block *(*read_super) (struct super_block *, void *, int);
 304         char *name;
 305         int requires_dev;
 306 };
 307 
 308 #ifdef __KERNEL__
 309 
 310 asmlinkage int sys_open(const char *, int, int);
 311 asmlinkage int sys_close(unsigned int);         /* yes, it's really unsigned */
 312 
 313 extern int getname(const char * filename, char **result);
 314 extern void putname(char * name);
 315 
 316 extern int register_blkdev(unsigned int, const char *, struct file_operations *);
 317 extern int blkdev_open(struct inode * inode, struct file * filp);
 318 extern struct file_operations def_blk_fops;
 319 extern struct inode_operations blkdev_inode_operations;
 320 
 321 extern int register_chrdev(unsigned int, const char *, struct file_operations *);
 322 extern int unregister_chrdev( unsigned int major, const char * name);
 323 extern int chrdev_open(struct inode * inode, struct file * filp);
 324 extern struct file_operations def_chr_fops;
 325 extern struct inode_operations chrdev_inode_operations;
 326 
 327 extern void init_fifo(struct inode * inode);
 328 
 329 extern struct file_operations connecting_fifo_fops;
 330 extern struct file_operations read_fifo_fops;
 331 extern struct file_operations write_fifo_fops;
 332 extern struct file_operations rdwr_fifo_fops;
 333 extern struct file_operations read_pipe_fops;
 334 extern struct file_operations write_pipe_fops;
 335 extern struct file_operations rdwr_pipe_fops;
 336 
 337 extern struct file_system_type *get_fs_type(char *name);
 338 
 339 extern int fs_may_mount(dev_t dev);
 340 extern int fs_may_umount(dev_t dev, struct inode * mount_root);
 341 extern int fs_may_remount_ro(dev_t dev);
 342 
 343 extern struct file *first_file;
 344 extern int nr_files;
 345 extern struct super_block super_blocks[NR_SUPER];
 346 
 347 extern int shrink_buffers(unsigned int priority);
 348 
 349 extern int nr_buffers;
 350 extern int buffermem;
 351 extern int nr_buffer_heads;
 352 
 353 extern void check_disk_change(dev_t dev);
 354 extern void invalidate_inodes(dev_t dev);
 355 extern void invalidate_buffers(dev_t dev);
 356 extern int floppy_change(struct buffer_head * first_block);
 357 extern void sync_inodes(dev_t dev);
 358 extern void sync_dev(dev_t dev);
 359 extern int fsync_dev(dev_t dev);
 360 extern void sync_supers(dev_t dev);
 361 extern int bmap(struct inode * inode,int block);
 362 extern int notify_change(int flags, struct inode * inode);
 363 extern int namei(const char * pathname, struct inode ** res_inode);
 364 extern int lnamei(const char * pathname, struct inode ** res_inode);
 365 extern int permission(struct inode * inode,int mask);
 366 extern int open_namei(const char * pathname, int flag, int mode,
 367         struct inode ** res_inode, struct inode * base);
 368 extern int do_mknod(const char * filename, int mode, dev_t dev);
 369 extern void iput(struct inode * inode);
 370 extern struct inode * __iget(struct super_block * sb,int nr,int crsmnt);
 371 extern struct inode * iget(struct super_block * sb,int nr);
 372 extern struct inode * get_empty_inode(void);
 373 extern void insert_inode_hash(struct inode *);
 374 extern void clear_inode(struct inode *);
 375 extern struct inode * get_pipe_inode(void);
 376 extern struct file * get_empty_filp(void);
 377 extern struct buffer_head * get_hash_table(dev_t dev, int block, int size);
 378 extern struct buffer_head * getblk(dev_t dev, int block, int size);
 379 extern void ll_rw_block(int rw, int nr, struct buffer_head * bh[]);
 380 extern void ll_rw_page(int rw, int dev, int nr, char * buffer);
 381 extern void ll_rw_swap_file(int rw, int dev, unsigned int *b, int nb, char *buffer);
 382 extern void brelse(struct buffer_head * buf);
 383 extern void set_blocksize(dev_t dev, int size);
 384 extern struct buffer_head * bread(dev_t dev, int block, int size);
 385 extern unsigned long bread_page(unsigned long addr,dev_t dev,int b[],int size,int prot);
 386 extern struct buffer_head * breada(dev_t dev,int block,...);
 387 extern void put_super(dev_t dev);
 388 extern dev_t ROOT_DEV;
 389 
 390 extern void mount_root(void);
 391 
 392 extern int char_read(struct inode *, struct file *, char *, int);
 393 extern int block_read(struct inode *, struct file *, char *, int);
 394 extern int read_ahead[];
 395 
 396 extern int char_write(struct inode *, struct file *, char *, int);
 397 extern int block_write(struct inode *, struct file *, char *, int);
 398 
 399 extern int generic_mmap(struct inode *, struct file *, unsigned long, size_t, int, unsigned long);
 400 
 401 extern int block_fsync(struct inode *, struct file *);
 402 extern int file_fsync(struct inode *, struct file *);
 403 
 404 #endif /* __KERNEL__ */
 405 
 406 #endif

/* */