include/linux/fs.h

   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 #include <linux/list.h>
  19 #include <linux/dcache.h>
  20 #include <linux/stat.h>
  21
  22 #include <asm/atomic.h>
  23 #include <asm/bitops.h>
  24 #include <asm/cache.h>
  25
  26 struct poll_table_struct;
  27
  28
  29 /*
  30  * It's silly to have NR_OPEN bigger than NR_FILE, but I'll fix
  31  * that later. Anyway, now the file code is no longer dependent
  32  * on bitmaps in unsigned longs, but uses the new fd_set structure..
  33  *
  34  * Some programs (notably those using select()) may have to be
  35  * recompiled to take full advantage of the new limits..
  36  */
  37
  38 /* Fixed constants first: */
  39 #undef NR_OPEN
  40 #define NR_OPEN 1024
  41
  42 #define BLOCK_SIZE_BITS 10
  43 #define BLOCK_SIZE (1<<BLOCK_SIZE_BITS)
  44
  45 /* And dynamically-tunable limits and defaults: */
  46 extern int max_inodes;
  47 extern int max_files, nr_files, nr_free_files;
  48 extern int max_super_blocks, nr_super_blocks;
  49
  50 #define NR_FILE  4096   /* this can well be larger on a larger system */
  51 #define NR_RESERVED_FILES 10 /* reserved for root */
  52 #define NR_SUPER 256
  53
  54 #define MAY_EXEC 1
  55 #define MAY_WRITE 2
  56 #define MAY_READ 4
  57
  58 #define FMODE_READ 1
  59 #define FMODE_WRITE 2
  60
  61 #define READ 0
  62 #define WRITE 1
  63 #define READA 2         /* read-ahead  - don't block if no resources */
  64 #define WRITEA 3        /* write-ahead - don't block if no resources */
  65
  66 #ifndef NULL
  67 #define NULL ((void *) 0)
  68 #endif
  69
  70 #define NIL_FILP        ((struct file *)0)
  71 #define SEL_IN          1
  72 #define SEL_OUT         2
  73 #define SEL_EX          4
  74
  75 /* public flags for file_system_type */
  76 #define FS_REQUIRES_DEV 1
  77 #define FS_NO_DCACHE    2 /* Only dcache the necessary things. */
  78 #define FS_NO_PRELIM    4 /* prevent preloading of dentries, even if
  79                            * FS_NO_DCACHE is not set.
  80                            */
  81 #define FS_IBASKET      8 /* FS does callback to free_ibasket() if space gets low. */
  82
  83 /*
  84  * These are the fs-independent mount-flags: up to 16 flags are supported
  85  */
  86 #define MS_RDONLY        1      /* Mount read-only */
  87 #define MS_NOSUID        2      /* Ignore suid and sgid bits */
  88 #define MS_NODEV         4      /* Disallow access to device special files */
  89 #define MS_NOEXEC        8      /* Disallow program execution */
  90 #define MS_SYNCHRONOUS  16      /* Writes are synced at once */
  91 #define MS_REMOUNT      32      /* Alter flags of a mounted FS */
  92 #define MS_MANDLOCK     64      /* Allow mandatory locks on an FS */
  93 #define S_QUOTA         128     /* Quota initialized for file/directory/symlink */
  94 #define S_APPEND        256     /* Append-only file */
  95 #define S_IMMUTABLE     512     /* Immutable file */
  96 #define MS_NOATIME      1024    /* Do not update access times. */
  97 #define MS_NODIRATIME   2048    /* Do not update directory access times */
  98
  99 #define MS_ODD_RENAME   32768   /* Temporary stuff; will go away as soon
 100                                   * as nfs_rename() will be cleaned up
 101                                   */
 102
 103 /*
 104  * Flags that can be altered by MS_REMOUNT
 105  */
 106 #define MS_RMT_MASK     (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|\
 107                         MS_SYNCHRONOUS|MS_MANDLOCK|MS_NOATIME|MS_NODIRATIME)
 108
 109 /*
 110  * Magic mount flag number. Has to be or-ed to the flag values.
 111  */
 112 #define MS_MGC_VAL 0xC0ED0000   /* magic flag number to indicate "new" flags */
 113 #define MS_MGC_MSK 0xffff0000   /* magic flag number mask */
 114
 115 /*
 116  * Note that nosuid etc flags are inode-specific: setting some file-system
 117  * flags just means all the inodes inherit those flags by default. It might be
 118  * possible to override it selectively if you really wanted to with some
 119  * ioctl() that is not currently implemented.
 120  *
 121  * Exception: MS_RDONLY is always applied to the entire file system.
 122  *
 123  * Unfortunately, it is possible to change a filesystems flags with it mounted
 124  * with files in use.  This means that all of the inodes will not have their
 125  * i_flags updated.  Hence, i_flags no longer inherit the superblock mount
 126  * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
 127  */
 128 #define __IS_FLG(inode,flg) (((inode)->i_sb && (inode)->i_sb->s_flags & (flg)) \
 129                                 || (inode)->i_flags & (flg))
 130
 131 #define IS_RDONLY(inode) (((inode)->i_sb) && ((inode)->i_sb->s_flags & MS_RDONLY))
 132 #define IS_NOSUID(inode)        __IS_FLG(inode, MS_NOSUID)
 133 #define IS_NODEV(inode)         __IS_FLG(inode, MS_NODEV)
 134 #define IS_NOEXEC(inode)        __IS_FLG(inode, MS_NOEXEC)
 135 #define IS_SYNC(inode)          __IS_FLG(inode, MS_SYNCHRONOUS)
 136 #define IS_MANDLOCK(inode)      __IS_FLG(inode, MS_MANDLOCK)
 137
 138 #define IS_QUOTAINIT(inode)     ((inode)->i_flags & S_QUOTA)
 139 #define IS_APPEND(inode)        ((inode)->i_flags & S_APPEND)
 140 #define IS_IMMUTABLE(inode)     ((inode)->i_flags & S_IMMUTABLE)
 141 #define IS_NOATIME(inode)       __IS_FLG(inode, MS_NOATIME)
 142 #define IS_NODIRATIME(inode)    __IS_FLG(inode, MS_NODIRATIME)
 143
 144
 145 /* the read-only stuff doesn't really belong here, but any other place is
 146    probably as bad and I don't want to create yet another include file. */
 147
 148 #define BLKROSET   _IO(0x12,93) /* set device read-only (0 = read-write) */
 149 #define BLKROGET   _IO(0x12,94) /* get read-only status (0 = read_write) */
 150 #define BLKRRPART  _IO(0x12,95) /* re-read partition table */
 151 #define BLKGETSIZE _IO(0x12,96) /* return device size */
 152 #define BLKFLSBUF  _IO(0x12,97) /* flush buffer cache */
 153 #define BLKRASET   _IO(0x12,98) /* Set read ahead for block device */
 154 #define BLKRAGET   _IO(0x12,99) /* get current read ahead setting */
 155 #define BLKFRASET  _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
 156 #define BLKFRAGET  _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
 157 #define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
 158 #define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
 159 #define BLKSSZGET  _IO(0x12,104)/* get block device sector size */
 160 #if 0
 161 #define BLKPG      _IO(0x12,105)/* See blkpg.h */
 162 /* This was here just to show that the number is taken -
 163    probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */
 164 #endif
 165
 166
 167 #define BMAP_IOCTL 1            /* obsolete - kept for compatibility */
 168 #define FIBMAP     _IO(0x00,1)  /* bmap access */
 169 #define FIGETBSZ   _IO(0x00,2)  /* get the block size used for bmap */
 170
 171 #ifdef __KERNEL__
 172
 173 #include <asm/semaphore.h>
 174 #include <asm/byteorder.h>
 175
 176 extern void update_atime (struct inode *);
 177 #define UPDATE_ATIME(inode) update_atime (inode)
 178
 179 extern void buffer_init(unsigned long);
 180 extern void inode_init(void);
 181 extern void file_table_init(void);
 182 extern void dcache_init(void);
 183
 184 typedef char buffer_block[BLOCK_SIZE];
 185
 186 /* bh state bits */
 187 #define BH_Uptodate     0       /* 1 if the buffer contains valid data */
 188 #define BH_Dirty        1       /* 1 if the buffer is dirty */
 189 #define BH_Lock         2       /* 1 if the buffer is locked */
 190 #define BH_Req          3       /* 0 if the buffer has been invalidated */
 191 #define BH_Mapped       4       /* 1 if the buffer has a disk mapping */
 192 #define BH_New          5       /* 1 if the buffer is new and not yet written out */
 193 #define BH_Protected    6       /* 1 if the buffer is protected */
 194
 195 /*
 196  * Try to keep the most commonly used fields in single cache lines (16
 197  * bytes) to improve performance.  This ordering should be
 198  * particularly beneficial on 32-bit processors.
 199  *
 200  * We use the first 16 bytes for the data which is used in searches
 201  * over the block hash lists (ie. getblk() and friends).
 202  *
 203  * The second 16 bytes we use for lru buffer scans, as used by
 204  * sync_buffers() and refill_freelist().  -- sct
 205  */
 206 struct buffer_head {
 207         /* First cache line: */
 208         struct buffer_head *b_next;     /* Hash queue list */
 209         unsigned long b_blocknr;        /* block number */
 210         unsigned short b_size;          /* block size */
 211         unsigned short b_list;          /* List that this buffer appears */
 212         kdev_t b_dev;                   /* device (B_FREE = free) */
 213
 214         atomic_t b_count;               /* users using this block */
 215         kdev_t b_rdev;                  /* Real device */
 216         unsigned long b_state;          /* buffer state bitmap (see above) */
 217         unsigned long b_flushtime;      /* Time when (dirty) buffer should be written */
 218
 219         struct buffer_head *b_next_free;/* lru/free list linkage */
 220         struct buffer_head *b_prev_free;/* doubly linked list of buffers */
 221         struct buffer_head *b_this_page;/* circular list of buffers in one page */
 222         struct buffer_head *b_reqnext;  /* request queue */
 223
 224         struct buffer_head **b_pprev;   /* doubly linked list of hash-queue */
 225         char *b_data;                   /* pointer to data block (1024 bytes) */
 226         void (*b_end_io)(struct buffer_head *bh, int uptodate); /* I/O completion */
 227         void *b_dev_id;
 228
 229         unsigned long b_rsector;        /* Real buffer location on disk */
 230         wait_queue_head_t b_wait;
 231 };
 232
 233 typedef void (bh_end_io_t)(struct buffer_head *bh, int uptodate);
 234 void init_buffer(struct buffer_head *, bh_end_io_t *, void *);
 235
 236 #define __buffer_state(bh, state)       (((bh)->b_state & (1UL << BH_##state)) != 0)
 237
 238 #define buffer_uptodate(bh)     __buffer_state(bh,Uptodate)
 239 #define buffer_dirty(bh)        __buffer_state(bh,Dirty)
 240 #define buffer_locked(bh)       __buffer_state(bh,Lock)
 241 #define buffer_req(bh)          __buffer_state(bh,Req)
 242 #define buffer_mapped(bh)       __buffer_state(bh,Mapped)
 243 #define buffer_new(bh)          __buffer_state(bh,New)
 244 #define buffer_protected(bh)    __buffer_state(bh,Protected)
 245
 246 #define buffer_page(bh)         (mem_map + MAP_NR((bh)->b_data))
 247 #define touch_buffer(bh)        set_bit(PG_referenced, &buffer_page(bh)->flags)
 248
 249 #include <linux/pipe_fs_i.h>
 250 #include <linux/minix_fs_i.h>
 251 #include <linux/ext2_fs_i.h>
 252 #include <linux/hpfs_fs_i.h>
 253 #include <linux/ntfs_fs_i.h>
 254 #include <linux/msdos_fs_i.h>
 255 #include <linux/umsdos_fs_i.h>
 256 #include <linux/iso_fs_i.h>
 257 #include <linux/nfs_fs_i.h>
 258 #include <linux/sysv_fs_i.h>
 259 #include <linux/affs_fs_i.h>
 260 #include <linux/ufs_fs_i.h>
 261 #include <linux/efs_fs_i.h>
 262 #include <linux/coda_fs_i.h>
 263 #include <linux/romfs_fs_i.h>
 264 #include <linux/smb_fs_i.h>
 265 #include <linux/hfs_fs_i.h>
 266 #include <linux/adfs_fs_i.h>
 267 #include <linux/qnx4_fs_i.h>
 268
 269 /*
 270  * Attribute flags.  These should be or-ed together to figure out what
 271  * has been changed!
 272  */
 273 #define ATTR_MODE       1
 274 #define ATTR_UID        2
 275 #define ATTR_GID        4
 276 #define ATTR_SIZE       8
 277 #define ATTR_ATIME      16
 278 #define ATTR_MTIME      32
 279 #define ATTR_CTIME      64
 280 #define ATTR_ATIME_SET  128
 281 #define ATTR_MTIME_SET  256
 282 #define ATTR_FORCE      512     /* Not a change, but a change it */
 283 #define ATTR_ATTR_FLAG  1024
 284
 285 /*
 286  * This is the Inode Attributes structure, used for notify_change().  It
 287  * uses the above definitions as flags, to know which values have changed.
 288  * Also, in this manner, a Filesystem can look at only the values it cares
 289  * about.  Basically, these are the attributes that the VFS layer can
 290  * request to change from the FS layer.
 291  *
 292  * Derek Atkins <warlord@MIT.EDU> 94-10-20
 293  */
 294 struct iattr {
 295         unsigned int    ia_valid;
 296         umode_t         ia_mode;
 297         uid_t           ia_uid;
 298         gid_t           ia_gid;
 299         off_t           ia_size;
 300         time_t          ia_atime;
 301         time_t          ia_mtime;
 302         time_t          ia_ctime;
 303         unsigned int    ia_attr_flags;
 304 };
 305
 306 /*
 307  * This is the inode attributes flag definitions
 308  */
 309 #define ATTR_FLAG_SYNCRONOUS    1       /* Syncronous write */
 310 #define ATTR_FLAG_NOATIME       2       /* Don't update atime */
 311 #define ATTR_FLAG_APPEND        4       /* Append-only file */
 312 #define ATTR_FLAG_IMMUTABLE     8       /* Immutable file */
 313 #define ATTR_FLAG_NODIRATIME    16      /* Don't update atime for directory */
 314
 315 /*
 316  * Includes for diskquotas and mount structures.
 317  */
 318 #include <linux/quota.h>
 319 #include <linux/mount.h>
 320
 321 struct inode {
 322         struct list_head        i_hash;
 323         struct list_head        i_list;
 324         struct list_head        i_dentry;
 325
 326         unsigned long           i_ino;
 327         unsigned int            i_count;
 328         kdev_t                  i_dev;
 329         umode_t                 i_mode;
 330         nlink_t                 i_nlink;
 331         uid_t                   i_uid;
 332         gid_t                   i_gid;
 333         kdev_t                  i_rdev;
 334         off_t                   i_size;
 335         time_t                  i_atime;
 336         time_t                  i_mtime;
 337         time_t                  i_ctime;
 338         unsigned long           i_blksize;
 339         unsigned long           i_blocks;
 340         unsigned long           i_version;
 341         unsigned long           i_nrpages;
 342         struct semaphore        i_sem;
 343         struct inode_operations *i_op;
 344         struct super_block      *i_sb;
 345         wait_queue_head_t       i_wait;
 346         struct file_lock        *i_flock;
 347         struct vm_area_struct   *i_mmap;
 348         struct page             *i_pages;
 349         struct dquot            *i_dquot[MAXQUOTAS];
 350         struct pipe_inode_info  *i_pipe;
 351
 352         unsigned long           i_state;
 353
 354         unsigned int            i_flags;
 355         unsigned char           i_sock;
 356
 357         int                     i_writecount;
 358         unsigned int            i_attr_flags;
 359         __u32                   i_generation;
 360         union {
 361                 struct minix_inode_info         minix_i;
 362                 struct ext2_inode_info          ext2_i;
 363                 struct hpfs_inode_info          hpfs_i;
 364                 struct ntfs_inode_info          ntfs_i;
 365                 struct msdos_inode_info         msdos_i;
 366                 struct umsdos_inode_info        umsdos_i;
 367                 struct iso_inode_info           isofs_i;
 368                 struct nfs_inode_info           nfs_i;
 369                 struct sysv_inode_info          sysv_i;
 370                 struct affs_inode_info          affs_i;
 371                 struct ufs_inode_info           ufs_i;
 372                 struct efs_inode_info           efs_i;
 373                 struct romfs_inode_info         romfs_i;
 374                 struct coda_inode_info          coda_i;
 375                 struct smb_inode_info           smbfs_i;
 376                 struct hfs_inode_info           hfs_i;
 377                 struct adfs_inode_info          adfs_i;
 378                 struct qnx4_inode_info          qnx4_i;
 379                 struct socket                   socket_i;
 380                 void                            *generic_ip;
 381         } u;
 382 };
 383
 384 /* Inode state bits.. */
 385 #define I_DIRTY         1
 386 #define I_LOCK          2
 387 #define I_FREEING       4
 388
 389 extern void __mark_inode_dirty(struct inode *);
 390 static inline void mark_inode_dirty(struct inode *inode)
 391 {
 392         if (!(inode->i_state & I_DIRTY))
 393                 __mark_inode_dirty(inode);
 394 }
 395
 396 struct fown_struct {
 397         int pid;                /* pid or -pgrp where SIGIO should be sent */
 398         uid_t uid, euid;        /* uid/euid of process setting the owner */
 399         int signum;             /* posix.1b rt signal to be delivered on IO */
 400 };
 401
 402 struct file {
 403         struct file             *f_next, **f_pprev;
 404         struct dentry           *f_dentry;
 405         struct file_operations  *f_op;
 406         atomic_t                f_count;
 407         unsigned int            f_flags;
 408         mode_t                  f_mode;
 409         loff_t                  f_pos;
 410         unsigned long           f_reada, f_ramax, f_raend, f_ralen, f_rawin;
 411         struct fown_struct      f_owner;
 412         unsigned int            f_uid, f_gid;
 413         int                     f_error;
 414
 415         unsigned long           f_version;
 416
 417         /* needed for tty driver, and maybe others */
 418         void                    *private_data;
 419 };
 420
 421 #define get_file(x)     atomic_inc(&(x)->f_count)
 422 #define file_count(x)   atomic_read(&(x)->f_count)
 423
 424 extern int init_private_file(struct file *, struct dentry *, int);
 425
 426 #define FL_POSIX        1
 427 #define FL_FLOCK        2
 428 #define FL_BROKEN       4       /* broken flock() emulation */
 429 #define FL_ACCESS       8       /* for processes suspended by mandatory locking */
 430 #define FL_LOCKD        16      /* lock held by rpc.lockd */
 431
 432 /*
 433  * The POSIX file lock owner is determined by
 434  * the "struct files_struct" in the thread group
 435  * (or NULL for no owner - BSD locks).
 436  *
 437  * Lockd stuffs a "host" pointer into this.
 438  */
 439 typedef struct files_struct *fl_owner_t;
 440
 441 struct file_lock {
 442         struct file_lock *fl_next;      /* singly linked list for this inode  */
 443         struct file_lock *fl_nextlink;  /* doubly linked list of all locks */
 444         struct file_lock *fl_prevlink;  /* used to simplify lock removal */
 445         struct file_lock *fl_nextblock; /* circular list of blocked processes */
 446         struct file_lock *fl_prevblock;
 447         fl_owner_t fl_owner;
 448         unsigned int fl_pid;
 449         wait_queue_head_t fl_wait;
 450         struct file *fl_file;
 451         unsigned char fl_flags;
 452         unsigned char fl_type;
 453         off_t fl_start;
 454         off_t fl_end;
 455
 456         void (*fl_notify)(struct file_lock *);  /* unblock callback */
 457
 458         union {
 459                 struct nfs_lock_info    nfs_fl;
 460         } fl_u;
 461 };
 462
 463 extern struct file_lock                 *file_lock_table;
 464
 465 #include <linux/fcntl.h>
 466
 467 extern int fcntl_getlk(unsigned int, struct flock *);
 468 extern int fcntl_setlk(unsigned int, unsigned int, struct flock *);
 469
 470 /* fs/locks.c */
 471 extern void locks_remove_posix(struct file *, fl_owner_t);
 472 extern void locks_remove_flock(struct file *);
 473 extern struct file_lock *posix_test_lock(struct file *, struct file_lock *);
 474 extern int posix_lock_file(struct file *, struct file_lock *, unsigned int);
 475 extern void posix_block_lock(struct file_lock *, struct file_lock *);
 476 extern void posix_unblock_lock(struct file_lock *);
 477
 478 struct fasync_struct {
 479         int     magic;
 480         int     fa_fd;
 481         struct  fasync_struct   *fa_next; /* singly linked list */
 482         struct  file            *fa_file;
 483 };
 484
 485 #define FASYNC_MAGIC 0x4601
 486
 487 extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
 488
 489 #include <linux/minix_fs_sb.h>
 490 #include <linux/ext2_fs_sb.h>
 491 #include <linux/hpfs_fs_sb.h>
 492 #include <linux/ntfs_fs_sb.h>
 493 #include <linux/msdos_fs_sb.h>
 494 #include <linux/iso_fs_sb.h>
 495 #include <linux/nfs_fs_sb.h>
 496 #include <linux/sysv_fs_sb.h>
 497 #include <linux/affs_fs_sb.h>
 498 #include <linux/ufs_fs_sb.h>
 499 #include <linux/efs_fs_sb.h>
 500 #include <linux/romfs_fs_sb.h>
 501 #include <linux/smb_fs_sb.h>
 502 #include <linux/hfs_fs_sb.h>
 503 #include <linux/adfs_fs_sb.h>
 504 #include <linux/qnx4_fs_sb.h>
 505
 506 extern struct list_head super_blocks;
 507
 508 #define sb_entry(list)  list_entry((list), struct super_block, s_list)
 509 struct super_block {
 510         struct list_head        s_list;         /* Keep this first */
 511         kdev_t                  s_dev;
 512         unsigned long           s_blocksize;
 513         unsigned char           s_blocksize_bits;
 514         unsigned char           s_lock;
 515         unsigned char           s_rd_only;
 516         unsigned char           s_dirt;
 517         struct file_system_type *s_type;
 518         struct super_operations *s_op;
 519         struct dquot_operations *dq_op;
 520         unsigned long           s_flags;
 521         unsigned long           s_magic;
 522         unsigned long           s_time;
 523         struct dentry           *s_root;
 524         wait_queue_head_t       s_wait;
 525
 526         struct inode            *s_ibasket;
 527         short int               s_ibasket_count;
 528         short int               s_ibasket_max;
 529         struct list_head        s_dirty;        /* dirty inodes */
 530
 531         union {
 532                 struct minix_sb_info    minix_sb;
 533                 struct ext2_sb_info     ext2_sb;
 534                 struct hpfs_sb_info     hpfs_sb;
 535                 struct ntfs_sb_info     ntfs_sb;
 536                 struct msdos_sb_info    msdos_sb;
 537                 struct isofs_sb_info    isofs_sb;
 538                 struct nfs_sb_info      nfs_sb;
 539                 struct sysv_sb_info     sysv_sb;
 540                 struct affs_sb_info     affs_sb;
 541                 struct ufs_sb_info      ufs_sb;
 542                 struct efs_sb_info      efs_sb;
 543                 struct romfs_sb_info    romfs_sb;
 544                 struct smb_sb_info      smbfs_sb;
 545                 struct hfs_sb_info      hfs_sb;
 546                 struct adfs_sb_info     adfs_sb;
 547                 struct qnx4_sb_info     qnx4_sb;
 548                 void                    *generic_sbp;
 549         } u;
 550         /*
 551          * The next field is for VFS *only*. No filesystems have any business
 552          * even looking at it. You had been warned.
 553          */
 554         struct semaphore s_vfs_rename_sem;      /* Kludge */
 555 };
 556
 557 /*
 558  * VFS helper functions..
 559  */
 560 extern int vfs_rmdir(struct inode *, struct dentry *);
 561 extern int vfs_unlink(struct inode *, struct dentry *);
 562 extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
 563
 564 /*
 565  * This is the "filldir" function type, used by readdir() to let
 566  * the kernel specify what kind of dirent layout it wants to have.
 567  * This allows the kernel to read directories into kernel space or
 568  * to have different dirent layouts depending on the binary type.
 569  */
 570 typedef int (*filldir_t)(void *, const char *, int, off_t, ino_t);
 571
 572 struct file_operations {
 573         loff_t (*llseek) (struct file *, loff_t, int);
 574         ssize_t (*read) (struct file *, char *, size_t, loff_t *);
 575         ssize_t (*write) (struct file *, const char *, size_t, loff_t *);
 576         int (*readdir) (struct file *, void *, filldir_t);
 577         unsigned int (*poll) (struct file *, struct poll_table_struct *);
 578         int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
 579         int (*mmap) (struct file *, struct vm_area_struct *);
 580         int (*open) (struct inode *, struct file *);
 581         int (*flush) (struct file *);
 582         int (*release) (struct inode *, struct file *);
 583         int (*fsync) (struct file *, struct dentry *);
 584         int (*fasync) (int, struct file *, int);
 585         int (*check_media_change) (kdev_t dev);
 586         int (*revalidate) (kdev_t dev);
 587         int (*lock) (struct file *, int, struct file_lock *);
 588 };
 589
 590 struct inode_operations {
 591         struct file_operations * default_file_ops;
 592         int (*create) (struct inode *,struct dentry *,int);
 593         struct dentry * (*lookup) (struct inode *,struct dentry *);
 594         int (*link) (struct dentry *,struct inode *,struct dentry *);
 595         int (*unlink) (struct inode *,struct dentry *);
 596         int (*symlink) (struct inode *,struct dentry *,const char *);
 597         int (*mkdir) (struct inode *,struct dentry *,int);
 598         int (*rmdir) (struct inode *,struct dentry *);
 599         int (*mknod) (struct inode *,struct dentry *,int,int);
 600         int (*rename) (struct inode *, struct dentry *,
 601                         struct inode *, struct dentry *);
 602         int (*readlink) (struct dentry *, char *,int);
 603         struct dentry * (*follow_link) (struct dentry *, struct dentry *, unsigned int);
 604         /*
 605          * the order of these functions within the VFS template has been
 606          * changed because SMP locking has changed: from now on all get_block,
 607          * readpage, writepage and flushpage functions are supposed to do
 608          * whatever locking they need to get proper SMP operation - for
 609          * now in most cases this means a lock/unlock_kernel at entry/exit.
 610          * [The new order is also slightly more logical :)]
 611          */
 612         /*
 613          * Generic block allocator exported by the lowlevel fs. All metadata
 614          * details are handled by the lowlevel fs, all 'logical data content'
 615          * details are handled by the highlevel block layer.
 616          */
 617         int (*get_block) (struct inode *, long, struct buffer_head *, int);
 618
 619         int (*readpage) (struct file *, struct page *);
 620         int (*writepage) (struct file *, struct page *);
 621         int (*flushpage) (struct inode *, struct page *, unsigned long);
 622
 623         void (*truncate) (struct inode *);
 624         int (*permission) (struct inode *, int);
 625         int (*smap) (struct inode *,int);
 626         int (*revalidate) (struct dentry *);
 627 };
 628
 629 struct super_operations {
 630         void (*read_inode) (struct inode *);
 631         void (*write_inode) (struct inode *);
 632         void (*put_inode) (struct inode *);
 633         void (*delete_inode) (struct inode *);
 634         int (*notify_change) (struct dentry *, struct iattr *);
 635         void (*put_super) (struct super_block *);
 636         void (*write_super) (struct super_block *);
 637         int (*statfs) (struct super_block *, struct statfs *, int);
 638         int (*remount_fs) (struct super_block *, int *, char *);
 639         void (*clear_inode) (struct inode *);
 640         void (*umount_begin) (struct super_block *);
 641 };
 642
 643 struct dquot_operations {
 644         void (*initialize) (struct inode *, short);
 645         void (*drop) (struct inode *);
 646         int (*alloc_block) (const struct inode *, unsigned long, uid_t, char);
 647         int (*alloc_inode) (const struct inode *, unsigned long, uid_t);
 648         void (*free_block) (const struct inode *, unsigned long);
 649         void (*free_inode) (const struct inode *, unsigned long);
 650         int (*transfer) (struct inode *, struct iattr *, char, uid_t);
 651 };
 652
 653 struct file_system_type {
 654         const char *name;
 655         int fs_flags;
 656         struct super_block *(*read_super) (struct super_block *, void *, int);
 657         struct file_system_type * next;
 658 };
 659
 660 extern int register_filesystem(struct file_system_type *);
 661 extern int unregister_filesystem(struct file_system_type *);
 662
 663
 664 #define FLOCK_VERIFY_READ  1
 665 #define FLOCK_VERIFY_WRITE 2
 666
 667 extern int locks_mandatory_locked(struct inode *);
 668 extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);
 669
 670 /*
 671  * Candidates for mandatory locking have the setgid bit set
 672  * but no group execute bit -  an otherwise meaningless combination.
 673  */
 674 #define MANDATORY_LOCK(inode) \
 675         (IS_MANDLOCK(inode) && ((inode)->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
 676
 677 static inline int locks_verify_locked(struct inode *inode)
 678 {
 679         if (MANDATORY_LOCK(inode))
 680                 return locks_mandatory_locked(inode);
 681         return 0;
 682 }
 683
 684 extern inline int locks_verify_area(int read_write, struct inode *inode,
 685                                     struct file *filp, loff_t offset,
 686                                     size_t count)
 687 {
 688         if (inode->i_flock && MANDATORY_LOCK(inode))
 689                 return locks_mandatory_area(read_write, inode, filp, offset, count);
 690         return 0;
 691 }
 692
 693
 694 /* fs/open.c */
 695
 696 asmlinkage int sys_open(const char *, int, int);
 697 asmlinkage int sys_close(unsigned int);         /* yes, it's really unsigned */
 698 extern int do_truncate(struct dentry *, unsigned long);
 699 extern int get_unused_fd(void);
 700 extern void put_unused_fd(unsigned int);
 701
 702 extern struct file *filp_open(const char *, int, int);
 703 extern int filp_close(struct file *, fl_owner_t id);
 704
 705 extern char * getname(const char *);
 706 #define __getname()     ((char *) __get_free_page(GFP_KERNEL))
 707 #define putname(name)   free_page((unsigned long)(name))
 708
 709 extern void kill_fasync(struct fasync_struct *, int);
 710 extern int register_blkdev(unsigned int, const char *, struct file_operations *);
 711 extern int unregister_blkdev(unsigned int, const char *);
 712 extern int blkdev_open(struct inode *, struct file *);
 713 extern int blkdev_release (struct inode *);
 714 extern struct file_operations def_blk_fops;
 715 extern struct inode_operations blkdev_inode_operations;
 716
 717 /* fs/devices.c */
 718 extern int register_chrdev(unsigned int, const char *, struct file_operations *);
 719 extern int unregister_chrdev(unsigned int, const char *);
 720 extern int chrdev_open(struct inode *, struct file *);
 721 extern struct file_operations def_chr_fops;
 722 extern struct inode_operations chrdev_inode_operations;
 723 extern char * bdevname(kdev_t);
 724 extern char * cdevname(kdev_t);
 725 extern char * kdevname(kdev_t);
 726 extern void init_special_inode(struct inode *, umode_t, int);
 727
 728 extern void init_fifo(struct inode *);
 729 extern struct inode_operations fifo_inode_operations;
 730
 731 /* Invalid inode operations -- fs/bad_inode.c */
 732 extern void make_bad_inode(struct inode *);
 733 extern int is_bad_inode(struct inode *);
 734
 735 extern struct file_operations connecting_fifo_fops;
 736 extern struct file_operations read_fifo_fops;
 737 extern struct file_operations write_fifo_fops;
 738 extern struct file_operations rdwr_fifo_fops;
 739 extern struct file_operations read_pipe_fops;
 740 extern struct file_operations write_pipe_fops;
 741 extern struct file_operations rdwr_pipe_fops;
 742
 743 extern struct file_system_type *get_fs_type(const char *);
 744
 745 extern int fs_may_remount_ro(struct super_block *);
 746 extern int fs_may_mount(kdev_t);
 747
 748 extern struct file *inuse_filps;
 749
 750 extern int try_to_free_buffers(struct page *);
 751 extern void refile_buffer(struct buffer_head * buf);
 752
 753 extern atomic_t buffermem;
 754
 755 #define BUF_CLEAN       0
 756 #define BUF_LOCKED      1       /* Buffers scheduled for write */
 757 #define BUF_DIRTY       2       /* Dirty buffers, not yet scheduled for write */
 758 #define NR_LIST         3
 759
 760 /*
 761  * This is called by bh->b_end_io() handlers when I/O has completed.
 762  */
 763 extern inline void mark_buffer_uptodate(struct buffer_head * bh, int on)
 764 {
 765         if (on)
 766                 set_bit(BH_Uptodate, &bh->b_state);
 767         else
 768                 clear_bit(BH_Uptodate, &bh->b_state);
 769 }
 770
 771 #define atomic_set_buffer_clean(bh) test_and_clear_bit(BH_Dirty, &(bh)->b_state)
 772
 773 extern inline void __mark_buffer_clean(struct buffer_head *bh)
 774 {
 775         refile_buffer(bh);
 776 }
 777
 778 extern inline void mark_buffer_clean(struct buffer_head * bh)
 779 {
 780         if (atomic_set_buffer_clean(bh))
 781                 __mark_buffer_clean(bh);
 782 }
 783
 784 extern void FASTCALL(__mark_buffer_dirty(struct buffer_head *bh, int flag));
 785
 786 #define atomic_set_buffer_dirty(bh) test_and_set_bit(BH_Dirty, &(bh)->b_state)
 787
 788 extern inline void mark_buffer_dirty(struct buffer_head * bh, int flag)
 789 {
 790         if (!atomic_set_buffer_dirty(bh))
 791                 __mark_buffer_dirty(bh, flag);
 792 }
 793
 794 extern void balance_dirty(kdev_t);
 795 extern int check_disk_change(kdev_t);
 796 extern int invalidate_inodes(struct super_block *);
 797 extern void invalidate_inode_pages(struct inode *);
 798 extern void invalidate_buffers(kdev_t);
 799 extern int floppy_is_wp(int);
 800 extern void sync_inodes(kdev_t);
 801 extern void write_inode_now(struct inode *);
 802 extern void sync_dev(kdev_t);
 803 extern int fsync_dev(kdev_t);
 804 extern void sync_supers(kdev_t);
 805 extern int bmap(struct inode *, int);
 806 extern int notify_change(struct dentry *, struct iattr *);
 807 extern int permission(struct inode *, int);
 808 extern int get_write_access(struct inode *);
 809 extern void put_write_access(struct inode *);
 810 extern struct dentry * open_namei(const char *, int, int);
 811 extern struct dentry * do_mknod(const char *, int, dev_t);
 812 extern int do_pipe(int *);
 813
 814 /* fs/dcache.c -- generic fs support functions */
 815 extern int is_subdir(struct dentry *, struct dentry *);
 816 extern ino_t find_inode_number(struct dentry *, struct qstr *);
 817
 818 /*
 819  * Kernel pointers have redundant information, so we can use a
 820  * scheme where we can return either an error code or a dentry
 821  * pointer with the same return value.
 822  *
 823  * This should be a per-architecture thing, to allow different
 824  * error and pointer decisions.
 825  */
 826 #define ERR_PTR(err)    ((void *)((long)(err)))
 827 #define PTR_ERR(ptr)    ((long)(ptr))
 828 #define IS_ERR(ptr)     ((unsigned long)(ptr) > (unsigned long)(-1000))
 829
 830 /*
 831  * The bitmask for a lookup event:
 832  *  - follow links at the end
 833  *  - require a directory
 834  *  - ending slashes ok even for nonexistent files
 835  *  - internal "there are more path compnents" flag
 836  */
 837 #define LOOKUP_FOLLOW           (1)
 838 #define LOOKUP_DIRECTORY        (2)
 839 #define LOOKUP_SLASHOK          (4)
 840 #define LOOKUP_CONTINUE         (8)
 841
 842 extern struct dentry * lookup_dentry(const char *, struct dentry *, unsigned int);
 843 extern struct dentry * __namei(const char *, unsigned int);
 844
 845 #define namei(pathname)         __namei(pathname, 1)
 846 #define lnamei(pathname)        __namei(pathname, 0)
 847
 848 extern void iput(struct inode *);
 849 extern struct inode * igrab(struct inode *);
 850 extern ino_t iunique(struct super_block *, ino_t);
 851 extern struct inode * iget(struct super_block *, unsigned long);
 852 extern void clear_inode(struct inode *);
 853 extern struct inode * get_empty_inode(void);
 854
 855 extern void insert_inode_hash(struct inode *);
 856 extern void remove_inode_hash(struct inode *);
 857 extern struct file * get_empty_filp(void);
 858 extern struct buffer_head * get_hash_table(kdev_t, int, int);
 859 extern struct buffer_head * getblk(kdev_t, int, int);
 860 extern void ll_rw_block(int, int, struct buffer_head * bh[]);
 861 extern int is_read_only(kdev_t);
 862 extern void __brelse(struct buffer_head *);
 863 extern inline void brelse(struct buffer_head *buf)
 864 {
 865         if (buf)
 866                 __brelse(buf);
 867 }
 868 extern void __bforget(struct buffer_head *);
 869 extern inline void bforget(struct buffer_head *buf)
 870 {
 871         if (buf)
 872                 __bforget(buf);
 873 }
 874 extern void set_blocksize(kdev_t, int);
 875 extern unsigned int get_hardblocksize(kdev_t);
 876 extern struct buffer_head * bread(kdev_t, int, int);
 877 extern struct buffer_head * breada(kdev_t, int, int, unsigned int, unsigned int);
 878
 879 extern int brw_page(int, struct page *, kdev_t, int [], int, int);
 880
 881 typedef int (*writepage_t)(struct file *, struct page *, unsigned long, unsigned long, const char *);
 882
 883 /* Generic buffer handling for block filesystems.. */
 884 extern int block_read_full_page(struct file *, struct page *);
 885 extern int block_write_full_page (struct file *, struct page *);
 886 extern int block_write_partial_page (struct file *, struct page *, unsigned long, unsigned long, const char *);
 887 extern int block_flushpage(struct inode *, struct page *, unsigned long);
 888
 889 extern int generic_file_mmap(struct file *, struct vm_area_struct *);
 890 extern ssize_t generic_file_read(struct file *, char *, size_t, loff_t *);
 891 extern ssize_t generic_file_write(struct file *, const char *, size_t, loff_t *, writepage_t);
 892
 893
 894 extern struct super_block *get_super(kdev_t);
 895 extern void put_super(kdev_t);
 896 unsigned long generate_cluster(kdev_t, int b[], int);
 897 unsigned long generate_cluster_swab32(kdev_t, int b[], int);
 898 extern kdev_t ROOT_DEV;
 899
 900 extern void mount_root(void);
 901
 902 #ifdef CONFIG_BLK_DEV_INITRD
 903 extern kdev_t real_root_dev;
 904 extern int change_root(kdev_t, const char *);
 905 #endif
 906
 907 extern ssize_t char_read(struct file *, char *, size_t, loff_t *);
 908 extern ssize_t block_read(struct file *, char *, size_t, loff_t *);
 909 extern int read_ahead[];
 910
 911 extern ssize_t char_write(struct file *, const char *, size_t, loff_t *);
 912 extern ssize_t block_write(struct file *, const char *, size_t, loff_t *);
 913
 914 extern int block_fsync(struct file *, struct dentry *);
 915 extern int file_fsync(struct file *, struct dentry *);
 916 extern int generic_buffer_fdatasync(struct inode *inode, unsigned long start, unsigned long end);
 917
 918 extern int inode_change_ok(struct inode *, struct iattr *);
 919 extern void inode_setattr(struct inode *, struct iattr *);
 920
 921 /* kludge to get SCSI modules working */
 922 #include <linux/minix_fs.h>
 923 #include <linux/minix_fs_sb.h>
 924
 925 #endif /* __KERNEL__ */
 926
 927 #endif /* _LINUX_FS_H */