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 
  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_HASH 997
  31 #define NR_IHASH 131
  32 #define NR_FILE_LOCKS 64
  33 #define BLOCK_SIZE 1024
  34 #define BLOCK_SIZE_BITS 10
  35 
  36 #define MAY_EXEC 1
  37 #define MAY_WRITE 2
  38 #define MAY_READ 4
  39 
  40 #define READ 0
  41 #define WRITE 1
  42 #define READA 2         /* read-ahead - don't pause */
  43 #define WRITEA 3        /* "write-ahead" - silly, but somewhat useful */
  44 
  45 extern void buffer_init(void);
  46 extern unsigned long inode_init(unsigned long start, unsigned long end);
  47 extern unsigned long file_table_init(unsigned long start, unsigned long end);
  48 
  49 #define MAJOR(a) (int)((unsigned short)(a) >> 8)
  50 #define MINOR(a) (int)((unsigned short)(a) & 0xFF)
  51 
  52 #ifndef NULL
  53 #define NULL ((void *) 0)
  54 #endif
  55 
  56 #define NIL_FILP        ((struct file *)0)
  57 #define SEL_IN          1
  58 #define SEL_OUT         2
  59 #define SEL_EX          4
  60 
  61 /*
  62  * These are the fs-independent mount-flags: up to 16 flags are supported
  63  */
  64 #define MS_RDONLY    1 /* mount read-only */
  65 #define MS_NOSUID    2 /* ignore suid and sgid bits */
  66 #define MS_NODEV     4 /* disallow access to device special files */
  67 #define MS_NOEXEC    8 /* disallow program execution */
  68 #define MS_SYNC     16 /* writes are synced at once */
  69 #define MS_REMOUNT  32 /* alter flags of a mounted FS */
  70 
  71 /*
  72  * Flags that can be altered by MS_REMOUNT
  73  */
  74 #define MS_RMT_MASK (MS_RDONLY)
  75 
  76 /*
  77  * Magic mount flag number. Has to be or-ed to the flag values.
  78  */
  79 #define MS_MGC_VAL 0xC0ED0000 /* magic flag number to indicate "new" flags */
  80 #define MS_MGC_MSK 0xffff0000 /* magic flag number mask */
  81 
  82 /*
  83  * Note that read-only etc flags are inode-specific: setting some file-system
  84  * flags just means all the inodes inherit those flags by default. It might be
  85  * possible to overrride it sevelctively if you really wanted to with some
  86  * ioctl() that is not currently implemented.
  87  *
  88  * Exception: MS_RDONLY is always applied to the entire file system.
  89  */
  90 #define IS_RDONLY(inode) (((inode)->i_sb) && ((inode)->i_sb->s_flags & MS_RDONLY))
  91 #define IS_NOSUID(inode) ((inode)->i_flags & MS_NOSUID)
  92 #define IS_NODEV(inode) ((inode)->i_flags & MS_NODEV)
  93 #define IS_NOEXEC(inode) ((inode)->i_flags & MS_NOEXEC)
  94 #define IS_SYNC(inode) ((inode)->i_flags & MS_SYNC)
  95 
  96 /* the read-only stuff doesn't really belong here, but any other place is
  97    probably as bad and I don't want to create yet another include file. */
  98 
  99 #define BLKROSET 4701 /* set device read-only (0 = read-write) */
 100 #define BLKROGET 4702 /* get read-only status (0 = read_write) */
 101 #define BLKRRPART 4703 /* re-read partition table */
 102 #define BLKGETSIZE 4704 /* return device size */
 103 #define BLKFLSBUF 4705 /* flush buffer cache */
 104 
 105 /* These are a few other constants  only used by scsi  devices */
 106 
 107 #define SCSI_IOCTL_GET_IDLUN 0x5382
 108 
 109 /* Used to turn on and off tagged queueing for scsi devices */
 110 
 111 #define SCSI_IOCTL_TAGGED_ENABLE 0x5383
 112 #define SCSI_IOCTL_TAGGED_DISABLE 0x5384
 113 
 114 
 115 #define BMAP_IOCTL 1    /* obsolete - kept for compatibility */
 116 #define FIBMAP     1    /* bmap access */
 117 #define FIGETBSZ   2    /* get the block size used for bmap */
 118 
 119 /* these flags tell notify_change what is being changed */
 120 
 121 #define NOTIFY_SIZE     1
 122 #define NOTIFY_MODE     2
 123 #define NOTIFY_TIME     4
 124 #define NOTIFY_UIDGID   8
 125 
 126 typedef char buffer_block[BLOCK_SIZE];
 127 
 128 struct buffer_head {
 129         char * b_data;                  /* pointer to data block (1024 bytes) */
 130         unsigned long b_size;           /* block size */
 131         unsigned long b_blocknr;        /* block number */
 132         dev_t b_dev;                    /* device (0 = free) */
 133         unsigned short b_count;         /* users using this block */
 134         unsigned char b_uptodate;
 135         unsigned char b_dirt;           /* 0-clean,1-dirty */
 136         unsigned char b_lock;           /* 0 - ok, 1 -locked */
 137         unsigned char b_req;            /* 0 if the buffer has been invalidated */
 138         struct wait_queue * b_wait;
 139         struct buffer_head * b_prev;            /* doubly linked list of hash-queue */
 140         struct buffer_head * b_next;
 141         struct buffer_head * b_prev_free;       /* doubly linked list of buffers */
 142         struct buffer_head * b_next_free;
 143         struct buffer_head * b_this_page;       /* circular list of buffers in one page */
 144         struct buffer_head * b_reqnext;         /* request queue */
 145 };
 146 
 147 #include <linux/pipe_fs_i.h>
 148 #include <linux/minix_fs_i.h>
 149 #include <linux/ext_fs_i.h>
 150 #include <linux/ext2_fs_i.h>
 151 #include <linux/hpfs_fs_i.h>
 152 #include <linux/msdos_fs_i.h>
 153 #include <linux/iso_fs_i.h>
 154 #include <linux/nfs_fs_i.h>
 155 #include <linux/xia_fs_i.h>
 156 
 157 struct inode {
 158         dev_t           i_dev;
 159         unsigned long   i_ino;
 160         umode_t         i_mode;
 161         nlink_t         i_nlink;
 162         uid_t           i_uid;
 163         gid_t           i_gid;
 164         dev_t           i_rdev;
 165         off_t           i_size;
 166         time_t          i_atime;
 167         time_t          i_mtime;
 168         time_t          i_ctime;
 169         unsigned long   i_blksize;
 170         unsigned long   i_blocks;
 171         struct inode_operations * i_op;
 172         struct super_block * i_sb;
 173         struct wait_queue * i_wait;
 174         struct file_lock * i_flock;
 175         struct vm_area_struct * i_mmap;
 176         struct inode * i_next, * i_prev;
 177         struct inode * i_hash_next, * i_hash_prev;
 178         struct inode * i_bound_to, * i_bound_by;
 179         struct inode * i_mount;
 180         unsigned short i_count;
 181         unsigned short i_flags;
 182         unsigned char i_lock;
 183         unsigned char i_dirt;
 184         unsigned char i_pipe;
 185         unsigned char i_seek;
 186         unsigned char i_update;
 187         union {
 188                 struct pipe_inode_info pipe_i;
 189                 struct minix_inode_info minix_i;
 190                 struct ext_inode_info ext_i;
 191                 struct ext2_inode_info ext2_i;
 192                 struct hpfs_inode_info hpfs_i;
 193                 struct msdos_inode_info msdos_i;
 194                 struct iso_inode_info isofs_i;
 195                 struct nfs_inode_info nfs_i;
 196                 struct xiafs_inode_info xiafs_i;
 197         } u;
 198 };
 199 
 200 struct file {
 201         mode_t f_mode;
 202         dev_t f_rdev;                   /* needed for /dev/tty */
 203         off_t f_pos;
 204         unsigned short f_flags;
 205         unsigned short f_count;
 206         unsigned short f_reada;
 207         struct file *f_next, *f_prev;
 208         struct inode * f_inode;
 209         struct file_operations * f_op;
 210 };
 211 
 212 struct file_lock {
 213         struct file_lock *fl_next;      /* singly linked list */
 214         struct task_struct *fl_owner;   /* NULL if on free list, for sanity checks */
 215         unsigned int fl_fd;             /* File descriptor for this lock */
 216         struct wait_queue *fl_wait;
 217         char fl_type;
 218         char fl_whence;
 219         off_t fl_start;
 220         off_t fl_end;
 221 };
 222 
 223 #include <linux/minix_fs_sb.h>
 224 #include <linux/ext_fs_sb.h>
 225 #include <linux/ext2_fs_sb.h>
 226 #include <linux/hpfs_fs_sb.h>
 227 #include <linux/msdos_fs_sb.h>
 228 #include <linux/iso_fs_sb.h>
 229 #include <linux/nfs_fs_sb.h>
 230 #include <linux/xia_fs_sb.h>
 231 
 232 struct super_block {
 233         dev_t s_dev;
 234         unsigned long s_blocksize;
 235         unsigned char s_blocksize_bits;
 236         unsigned char s_lock;
 237         unsigned char s_rd_only;
 238         unsigned char s_dirt;
 239         struct super_operations *s_op;
 240         unsigned long s_flags;
 241         unsigned long s_magic;
 242         unsigned long s_time;
 243         struct inode * s_covered;
 244         struct inode * s_mounted;
 245         struct wait_queue * s_wait;
 246         union {
 247                 struct minix_sb_info minix_sb;
 248                 struct ext_sb_info ext_sb;
 249                 struct ext2_sb_info ext2_sb;
 250                 struct hpfs_sb_info hpfs_sb;
 251                 struct msdos_sb_info msdos_sb;
 252                 struct isofs_sb_info isofs_sb;
 253                 struct nfs_sb_info nfs_sb;
 254                 struct xiafs_sb_info xiafs_sb;
 255         } u;
 256 };
 257 
 258 struct file_operations {
 259         int (*lseek) (struct inode *, struct file *, off_t, int);
 260         int (*read) (struct inode *, struct file *, char *, int);
 261         int (*write) (struct inode *, struct file *, char *, int);
 262         int (*readdir) (struct inode *, struct file *, struct dirent *, int);
 263         int (*select) (struct inode *, struct file *, int, select_table *);
 264         int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
 265         int (*mmap) (struct inode *, struct file *, unsigned long, size_t, int, unsigned long);
 266         int (*open) (struct inode *, struct file *);
 267         void (*release) (struct inode *, struct file *);
 268         int (*fsync) (struct inode *, struct file *);
 269 };
 270 
 271 struct inode_operations {
 272         struct file_operations * default_file_ops;
 273         int (*create) (struct inode *,const char *,int,int,struct inode **);
 274         int (*lookup) (struct inode *,const char *,int,struct inode **);
 275         int (*link) (struct inode *,struct inode *,const char *,int);
 276         int (*unlink) (struct inode *,const char *,int);
 277         int (*symlink) (struct inode *,const char *,int,const char *);
 278         int (*mkdir) (struct inode *,const char *,int,int);
 279         int (*rmdir) (struct inode *,const char *,int);
 280         int (*mknod) (struct inode *,const char *,int,int,int);
 281         int (*rename) (struct inode *,const char *,int,struct inode *,const char *,int);
 282         int (*readlink) (struct inode *,char *,int);
 283         int (*follow_link) (struct inode *,struct inode *,int,int,struct inode **);
 284         int (*bmap) (struct inode *,int);
 285         void (*truncate) (struct inode *);
 286         int (*permission) (struct inode *, int);
 287 };
 288 
 289 struct super_operations {
 290         void (*read_inode) (struct inode *);
 291         int (*notify_change) (int flags, struct inode *);
 292         void (*write_inode) (struct inode *);
 293         void (*put_inode) (struct inode *);
 294         void (*put_super) (struct super_block *);
 295         void (*write_super) (struct super_block *);
 296         void (*statfs) (struct super_block *, struct statfs *);
 297         int (*remount_fs) (struct super_block *, int *);
 298 };
 299 
 300 struct file_system_type {
 301         struct super_block *(*read_super) (struct super_block *, void *, int);
 302         char *name;
 303         int requires_dev;
 304 };
 305 
 306 #ifdef __KERNEL__
 307 
 308 asmlinkage int sys_open(const char *, int, int);
 309 asmlinkage int sys_close(unsigned int);         /* yes, it's really unsigned */
 310 
 311 extern int getname(const char * filename, char **result);
 312 extern void putname(char * name);
 313 
 314 extern int register_blkdev(unsigned int, const char *, struct file_operations *);
 315 extern int blkdev_open(struct inode * inode, struct file * filp);
 316 extern struct file_operations def_blk_fops;
 317 extern struct inode_operations blkdev_inode_operations;
 318 
 319 extern int register_chrdev(unsigned int, const char *, struct file_operations *);
 320 extern int chrdev_open(struct inode * inode, struct file * filp);
 321 extern struct file_operations def_chr_fops;
 322 extern struct inode_operations chrdev_inode_operations;
 323 
 324 extern void init_fifo(struct inode * inode);
 325 
 326 extern struct file_operations connecting_fifo_fops;
 327 extern struct file_operations read_fifo_fops;
 328 extern struct file_operations write_fifo_fops;
 329 extern struct file_operations rdwr_fifo_fops;
 330 extern struct file_operations read_pipe_fops;
 331 extern struct file_operations write_pipe_fops;
 332 extern struct file_operations rdwr_pipe_fops;
 333 
 334 extern struct file_system_type *get_fs_type(char *name);
 335 
 336 extern int fs_may_mount(dev_t dev);
 337 extern int fs_may_umount(dev_t dev, struct inode * mount_root);
 338 extern int fs_may_remount_ro(dev_t dev);
 339 
 340 extern struct file *first_file;
 341 extern int nr_files;
 342 extern struct super_block super_blocks[NR_SUPER];
 343 
 344 extern int shrink_buffers(unsigned int priority);
 345 
 346 extern int nr_buffers;
 347 extern int buffermem;
 348 extern int nr_buffer_heads;
 349 
 350 extern void check_disk_change(dev_t dev);
 351 extern void invalidate_inodes(dev_t dev);
 352 extern void invalidate_buffers(dev_t dev);
 353 extern int floppy_change(struct buffer_head * first_block);
 354 extern void sync_inodes(dev_t dev);
 355 extern void sync_dev(dev_t dev);
 356 extern int fsync_dev(dev_t dev);
 357 extern void sync_supers(dev_t dev);
 358 extern int bmap(struct inode * inode,int block);
 359 extern int notify_change(int flags, struct inode * inode);
 360 extern int namei(const char * pathname, struct inode ** res_inode);
 361 extern int lnamei(const char * pathname, struct inode ** res_inode);
 362 extern int permission(struct inode * inode,int mask);
 363 extern int open_namei(const char * pathname, int flag, int mode,
 364         struct inode ** res_inode, struct inode * base);
 365 extern int do_mknod(const char * filename, int mode, dev_t dev);
 366 extern void iput(struct inode * inode);
 367 extern struct inode * __iget(struct super_block * sb,int nr,int crsmnt);
 368 extern struct inode * iget(struct super_block * sb,int nr);
 369 extern struct inode * get_empty_inode(void);
 370 extern void insert_inode_hash(struct inode *);
 371 extern void clear_inode(struct inode *);
 372 extern struct inode * get_pipe_inode(void);
 373 extern struct file * get_empty_filp(void);
 374 extern struct buffer_head * get_hash_table(dev_t dev, int block, int size);
 375 extern struct buffer_head * getblk(dev_t dev, int block, int size);
 376 extern void ll_rw_block(int rw, int nr, struct buffer_head * bh[]);
 377 extern void ll_rw_page(int rw, int dev, int nr, char * buffer);
 378 extern void ll_rw_swap_file(int rw, int dev, unsigned int *b, int nb, char *buffer);
 379 extern void brelse(struct buffer_head * buf);
 380 extern void set_blocksize(dev_t dev, int size);
 381 extern struct buffer_head * bread(dev_t dev, int block, int size);
 382 extern unsigned long bread_page(unsigned long addr,dev_t dev,int b[],int size,int prot);
 383 extern struct buffer_head * breada(dev_t dev,int block,...);
 384 extern void put_super(dev_t dev);
 385 extern dev_t ROOT_DEV;
 386 
 387 extern void mount_root(void);
 388 
 389 extern int char_read(struct inode *, struct file *, char *, int);
 390 extern int block_read(struct inode *, struct file *, char *, int);
 391 extern int read_ahead[];
 392 
 393 extern int char_write(struct inode *, struct file *, char *, int);
 394 extern int block_write(struct inode *, struct file *, char *, int);
 395 
 396 extern int generic_mmap(struct inode *, struct file *, unsigned long, size_t, int, unsigned long);
 397 
 398 extern int block_fsync(struct inode *, struct file *);
 399 extern int file_fsync(struct inode *, struct file *);
 400 
 401 #endif /* __KERNEL__ */
 402 
 403 #endif

/* */