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/limits.h>
  10 #include <linux/wait.h>
  11 #include <linux/types.h>
  12 #include <linux/dirent.h>
  13 #include <linux/vfs.h>
  14 
  15 /*
  16  * It's silly to have NR_OPEN bigger than NR_FILE, but I'll fix
  17  * that later. Anyway, now the file code is no longer dependent
  18  * on bitmaps in unsigned longs, but uses the new fd_set structure..
  19  *
  20  * Some programs (notably those using select()) may have to be 
  21  * recompiled to take full advantage of the new limits..
  22  */
  23 #undef NR_OPEN
  24 #define NR_OPEN 256
  25 
  26 #define NR_INODE 2048   /* this should be bigger than NR_FILE */
  27 #define NR_FILE 1024    /* this can well be larger on a larger system */
  28 #define NR_SUPER 32
  29 #define NR_HASH 997
  30 #define NR_IHASH 131
  31 #define NR_FILE_LOCKS 32
  32 #define BLOCK_SIZE 1024
  33 #define BLOCK_SIZE_BITS 10
  34 #define MAX_CHRDEV 32
  35 #define MAX_BLKDEV 32
  36 
  37 /* devices are as follows: (same as minix, so we can use the minix
  38  * file system. These are major numbers.)
  39  *
  40  *  0 - unnamed (minor 0 = true nodev)
  41  *  1 - /dev/mem
  42  *  2 - /dev/fd
  43  *  3 - /dev/hd
  44  *  4 - /dev/ttyx
  45  *  5 - /dev/tty
  46  *  6 - /dev/lp
  47  *  7 -
  48  *  8 - /dev/sd
  49  *  9 - /dev/st
  50  * 10 - mice
  51  * 11 - scsi cdrom
  52  * 12 -
  53  * 13 -
  54  * 14 - sound card (?)
  55  * 15 -
  56  */
  57 
  58 #define UNNAMED_MAJOR 0
  59 
  60 #define MAY_EXEC 1
  61 #define MAY_WRITE 2
  62 #define MAY_READ 4
  63 
  64 #define READ 0
  65 #define WRITE 1
  66 #define READA 2         /* read-ahead - don't pause */
  67 #define WRITEA 3        /* "write-ahead" - silly, but somewhat useful */
  68 
  69 extern void buffer_init(void);
  70 extern unsigned long inode_init(unsigned long start, unsigned long end);
  71 extern unsigned long file_table_init(unsigned long start, unsigned long end);
  72 
  73 #define MAJOR(a) (((unsigned)(a))>>8)
  74 #define MINOR(a) ((a)&0xff)
  75 
  76 #ifndef NULL
  77 #define NULL ((void *) 0)
  78 #endif
  79 
  80 #define NIL_FILP        ((struct file *)0)
  81 #define SEL_IN          1
  82 #define SEL_OUT         2
  83 #define SEL_EX          4
  84 
  85 /*
  86  * These are the fs-independent mount-flags: up to 16 flags are supported
  87  */
  88 #define MS_RDONLY    1 /* mount read-only */
  89 #define MS_NOSUID    2 /* ignore suid and sgid bits */
  90 #define MS_NODEV     4 /* disallow access to device special files */
  91 #define MS_NOEXEC    8 /* disallow program execution */
  92 #define MS_SYNC     16 /* writes are synced at once */
  93 #define MS_REMOUNT  32 /* alter flags of a mounted FS */
  94 
  95 /*
  96  * Flags that can be altered by MS_REMOUNT
  97  */
  98 #define MS_RMT_MASK (MS_RDONLY)
  99 
 100 /*
 101  * Magic mount flag number. Has to be or-ed to the flag values.
 102  */
 103 #define MS_MGC_VAL 0xC0ED0000 /* magic flag number to indicate "new" flags */
 104 #define MS_MGC_MSK 0xffff0000 /* magic flag number mask */
 105 
 106 /*
 107  * Note that read-only etc flags are inode-specific: setting some file-system
 108  * flags just means all the inodes inherit those flags by default. It might be
 109  * possible to overrride it sevelctively if you really wanted to with some
 110  * ioctl() that is not currently implemented.
 111  *
 112  * Exception: MS_RDONLY is always applied to the entire file system.
 113  */
 114 #define IS_RDONLY(inode) (((inode)->i_sb) && ((inode)->i_sb->s_flags & MS_RDONLY))
 115 #define IS_NOSUID(inode) ((inode)->i_flags & MS_NOSUID)
 116 #define IS_NODEV(inode) ((inode)->i_flags & MS_NODEV)
 117 #define IS_NOEXEC(inode) ((inode)->i_flags & MS_NOEXEC)
 118 #define IS_SYNC(inode) ((inode)->i_flags & MS_SYNC)
 119 
 120 /* the read-only stuff doesn't really belong here, but any other place is
 121    probably as bad and I don't want to create yet another include file. */
 122 
 123 #define BLKROSET 4701 /* set device read-only (0 = read-write) */
 124 #define BLKROGET 4702 /* get read-only status (0 = read_write) */
 125 #define BLKRRPART 4703 /* re-read partition table */
 126 #define BLKGETSIZE 4704 /* return device size */
 127 
 128 #define BMAP_IOCTL 1    /* obsolete - kept for compatibility */
 129 #define FIBMAP     1    /* bmap access */
 130 #define FIGETBSZ   2    /* get the block size used for bmap */
 131 
 132 /* these flags tell notify_change what is being changed */
 133 
 134 #define NOTIFY_SIZE     1
 135 #define NOTIFY_MODE     2
 136 #define NOTIFY_TIME     4
 137 #define NOTIFY_UIDGID   8
 138 
 139 typedef char buffer_block[BLOCK_SIZE];
 140 
 141 struct buffer_head {
 142         char * b_data;                  /* pointer to data block (1024 bytes) */
 143         unsigned long b_size;           /* block size */
 144         unsigned long b_blocknr;        /* block number */
 145         dev_t b_dev;                    /* device (0 = free) */
 146         unsigned short b_count;         /* users using this block */
 147         unsigned char b_uptodate;
 148         unsigned char b_dirt;           /* 0-clean,1-dirty */
 149         unsigned char b_lock;           /* 0 - ok, 1 -locked */
 150         unsigned char b_req;            /* 0 if the buffer has been invalidated */
 151         struct wait_queue * b_wait;
 152         struct buffer_head * b_prev;            /* doubly linked list of hash-queue */
 153         struct buffer_head * b_next;
 154         struct buffer_head * b_prev_free;       /* doubly linked list of buffers */
 155         struct buffer_head * b_next_free;
 156         struct buffer_head * b_this_page;       /* circular list of buffers in one page */
 157         struct buffer_head * b_reqnext;         /* request queue */
 158 };
 159 
 160 #include <linux/pipe_fs_i.h>
 161 #include <linux/minix_fs_i.h>
 162 #include <linux/ext_fs_i.h>
 163 #include <linux/ext2_fs_i.h>
 164 #include <linux/msdos_fs_i.h>
 165 #include <linux/iso_fs_i.h>
 166 #include <linux/nfs_fs_i.h>
 167 #include <linux/xia_fs_i.h>
 168 
 169 struct inode {
 170         dev_t           i_dev;
 171         unsigned long   i_ino;
 172         umode_t         i_mode;
 173         nlink_t         i_nlink;
 174         uid_t           i_uid;
 175         gid_t           i_gid;
 176         dev_t           i_rdev;
 177         off_t           i_size;
 178         time_t          i_atime;
 179         time_t          i_mtime;
 180         time_t          i_ctime;
 181         unsigned long   i_blksize;
 182         unsigned long   i_blocks;
 183         struct inode_operations * i_op;
 184         struct super_block * i_sb;
 185         struct wait_queue * i_wait;
 186         struct file_lock * i_flock;
 187         struct vm_area_struct * i_mmap;
 188         struct inode * i_next, * i_prev;
 189         struct inode * i_hash_next, * i_hash_prev;
 190         struct inode * i_bound_to, * i_bound_by;
 191         unsigned short i_count;
 192         unsigned short i_flags;
 193         unsigned char i_lock;
 194         unsigned char i_dirt;
 195         unsigned char i_pipe;
 196         unsigned char i_mount;
 197         unsigned char i_seek;
 198         unsigned char i_update;
 199         union {
 200                 struct pipe_inode_info pipe_i;
 201                 struct minix_inode_info minix_i;
 202                 struct ext_inode_info ext_i;
 203                 struct ext2_inode_info ext2_i;
 204                 struct msdos_inode_info msdos_i;
 205                 struct iso_inode_info isofs_i;
 206                 struct nfs_inode_info nfs_i;
 207                 struct xiafs_inode_info xiafs_i;
 208         } u;
 209 };
 210 
 211 struct file {
 212         mode_t f_mode;
 213         dev_t f_rdev;                   /* needed for /dev/tty */
 214         off_t f_pos;
 215         unsigned short f_flags;
 216         unsigned short f_count;
 217         unsigned short f_reada;
 218         struct file *f_next, *f_prev;
 219         struct inode * f_inode;
 220         struct file_operations * f_op;
 221 };
 222 
 223 struct file_lock {
 224         struct file_lock *fl_next;      /* singly linked list */
 225         struct task_struct *fl_owner;   /* NULL if on free list, for sanity checks */
 226         struct wait_queue *fl_wait;
 227         char fl_type;
 228         char fl_whence;
 229         off_t fl_start;
 230         off_t fl_end;
 231 };
 232 
 233 #include <linux/minix_fs_sb.h>
 234 #include <linux/ext_fs_sb.h>
 235 #include <linux/ext2_fs_sb.h>
 236 #include <linux/msdos_fs_sb.h>
 237 #include <linux/iso_fs_sb.h>
 238 #include <linux/nfs_fs_sb.h>
 239 #include <linux/xia_fs_sb.h>
 240 
 241 struct super_block {
 242         dev_t s_dev;
 243         unsigned long s_blocksize;
 244         unsigned char s_blocksize_bits;
 245         unsigned char s_lock;
 246         unsigned char s_rd_only;
 247         unsigned char s_dirt;
 248         struct super_operations *s_op;
 249         unsigned long s_flags;
 250         unsigned long s_magic;
 251         unsigned long s_time;
 252         struct inode * s_covered;
 253         struct inode * s_mounted;
 254         struct wait_queue * s_wait;
 255         union {
 256                 struct minix_sb_info minix_sb;
 257                 struct ext_sb_info ext_sb;
 258                 struct ext2_sb_info ext2_sb;
 259                 struct msdos_sb_info msdos_sb;
 260                 struct isofs_sb_info isofs_sb;
 261                 struct nfs_sb_info nfs_sb;
 262                 struct xiafs_sb_info xiafs_sb;
 263         } u;
 264 };
 265 
 266 struct file_operations {
 267         int (*lseek) (struct inode *, struct file *, off_t, int);
 268         int (*read) (struct inode *, struct file *, char *, int);
 269         int (*write) (struct inode *, struct file *, char *, int);
 270         int (*readdir) (struct inode *, struct file *, struct dirent *, int);
 271         int (*select) (struct inode *, struct file *, int, select_table *);
 272         int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
 273         int (*mmap) (struct inode *, struct file *, unsigned long, size_t, int, unsigned long);
 274         int (*open) (struct inode *, struct file *);
 275         void (*release) (struct inode *, struct file *);
 276         int (*fsync) (struct inode *, struct file *);
 277 };
 278 
 279 struct inode_operations {
 280         struct file_operations * default_file_ops;
 281         int (*create) (struct inode *,const char *,int,int,struct inode **);
 282         int (*lookup) (struct inode *,const char *,int,struct inode **);
 283         int (*link) (struct inode *,struct inode *,const char *,int);
 284         int (*unlink) (struct inode *,const char *,int);
 285         int (*symlink) (struct inode *,const char *,int,const char *);
 286         int (*mkdir) (struct inode *,const char *,int,int);
 287         int (*rmdir) (struct inode *,const char *,int);
 288         int (*mknod) (struct inode *,const char *,int,int,int);
 289         int (*rename) (struct inode *,const char *,int,struct inode *,const char *,int);
 290         int (*readlink) (struct inode *,char *,int);
 291         int (*follow_link) (struct inode *,struct inode *,int,int,struct inode **);
 292         int (*bmap) (struct inode *,int);
 293         void (*truncate) (struct inode *);
 294         int (*permission) (struct inode *, int);
 295 };
 296 
 297 struct super_operations {
 298         void (*read_inode) (struct inode *);
 299         int (*notify_change) (int flags, struct inode *);
 300         void (*write_inode) (struct inode *);
 301         void (*put_inode) (struct inode *);
 302         void (*put_super) (struct super_block *);
 303         void (*write_super) (struct super_block *);
 304         void (*statfs) (struct super_block *, struct statfs *);
 305         int (*remount_fs) (struct super_block *, int *);
 306 };
 307 
 308 struct file_system_type {
 309         struct super_block *(*read_super) (struct super_block *, void *, int);
 310         char *name;
 311         int requires_dev;
 312 };
 313 
 314 #ifdef __KERNEL__
 315 
 316 extern "C" int sys_open(const char *, int, int);
 317 extern "C" int sys_close(unsigned int);         /* yes, it's really unsigned */
 318 
 319 extern int getname(const char * filename, char **result);
 320 extern void putname(char * name);
 321 
 322 extern int register_blkdev(unsigned int, const char *, struct file_operations *);
 323 extern int blkdev_open(struct inode * inode, struct file * filp);
 324 extern struct file_operations def_blk_fops;
 325 extern struct inode_operations blkdev_inode_operations;
 326 
 327 extern int register_chrdev(unsigned int, const char *, struct file_operations *);
 328 extern int chrdev_open(struct inode * inode, struct file * filp);
 329 extern struct file_operations def_chr_fops;
 330 extern struct inode_operations chrdev_inode_operations;
 331 
 332 extern void init_fifo(struct inode * inode);
 333 
 334 extern struct file_operations connecting_pipe_fops;
 335 extern struct file_operations read_pipe_fops;
 336 extern struct file_operations write_pipe_fops;
 337 extern struct file_operations rdwr_pipe_fops;
 338 
 339 extern struct file_system_type *get_fs_type(char *name);
 340 
 341 extern int fs_may_mount(dev_t dev);
 342 extern int fs_may_umount(dev_t dev, struct inode * mount_root);
 343 extern int fs_may_remount_ro(dev_t dev);
 344 
 345 extern struct file *first_file;
 346 extern int nr_files;
 347 extern struct super_block super_blocks[NR_SUPER];
 348 
 349 extern void grow_buffers(int size);
 350 extern int shrink_buffers(unsigned int priority);
 351 
 352 extern int nr_buffers;
 353 extern int buffermem;
 354 extern int nr_buffer_heads;
 355 
 356 extern void check_disk_change(dev_t dev);
 357 extern void invalidate_inodes(dev_t dev);
 358 extern void invalidate_buffers(dev_t dev);
 359 extern int floppy_change(struct buffer_head * first_block);
 360 extern void sync_inodes(dev_t dev);
 361 extern void sync_dev(dev_t dev);
 362 extern int fsync_dev(dev_t dev);
 363 extern void sync_supers(dev_t dev);
 364 extern int bmap(struct inode * inode,int block);
 365 extern int notify_change(int flags, struct inode * inode);
 366 extern int namei(const char * pathname, struct inode ** res_inode);
 367 extern int lnamei(const char * pathname, struct inode ** res_inode);
 368 extern int permission(struct inode * inode,int mask);
 369 extern int open_namei(const char * pathname, int flag, int mode,
 370         struct inode ** res_inode, struct inode * base);
 371 extern int do_mknod(const char * filename, int mode, dev_t dev);
 372 extern void iput(struct inode * inode);
 373 extern struct inode * iget(struct super_block * sb,int nr);
 374 extern struct inode * get_empty_inode(void);
 375 extern void insert_inode_hash(struct inode *);
 376 extern void clear_inode(struct inode *);
 377 extern struct inode * get_pipe_inode(void);
 378 extern struct file * get_empty_filp(void);
 379 extern struct buffer_head * get_hash_table(dev_t dev, int block, int size);
 380 extern struct buffer_head * getblk(dev_t dev, int block, int size);
 381 extern void ll_rw_block(int rw, int nr, struct buffer_head * bh[]);
 382 extern void ll_rw_page(int rw, int dev, int nr, char * buffer);
 383 extern void ll_rw_swap_file(int rw, int dev, unsigned int *b, int nb, char *buffer);
 384 extern void brelse(struct buffer_head * buf);
 385 extern void set_blocksize(dev_t dev, int size);
 386 extern struct buffer_head * bread(dev_t dev, int block, int size);
 387 extern unsigned long bread_page(unsigned long addr,dev_t dev,int b[],int size,int prot);
 388 extern struct buffer_head * breada(dev_t dev,int block,...);
 389 extern void put_super(dev_t dev);
 390 extern dev_t ROOT_DEV;
 391 
 392 extern void mount_root(void);
 393 
 394 extern int char_read(struct inode *, struct file *, char *, int);
 395 extern int block_read(struct inode *, struct file *, char *, int);
 396 extern int read_ahead[];
 397 
 398 extern int char_write(struct inode *, struct file *, char *, int);
 399 extern int block_write(struct inode *, struct file *, char *, int);
 400 
 401 extern int generic_mmap(struct inode *, struct file *, unsigned long, size_t, int, unsigned long);
 402 
 403 extern int block_fsync(struct inode *, struct file *);
 404 extern int file_fsync(struct inode *, struct file *);
 405 
 406 #endif /* __KERNEL__ */
 407 
 408 #endif

/* */