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#ifndef _LINUX_FS_H
#define _LINUX_FS_H

/*
 * This file has definitions for some important file table
 * structures etc.
 */

#include <linux/config.h>
#include <linux/linkage.h>
#include <linux/limits.h>
#include <linux/wait.h>
#include <linux/types.h>
#include <linux/vfs.h>
#include <linux/net.h>
#include <linux/kdev_t.h>
#include <linux/ioctl.h>

#include <asm/atomic.h>
#include <asm/bitops.h>

/* Prefixes for routines (having no effect), but indicate what
 * the routine may do. This can greatly ease reasoning about routines...
 */
#define blocking /*routine may schedule()*/

/*
 * It's silly to have NR_OPEN bigger than NR_FILE, but I'll fix
 * that later. Anyway, now the file code is no longer dependent
 * on bitmaps in unsigned longs, but uses the new fd_set structure..
 *
 * Some programs (notably those using select()) may have to be 
 * recompiled to take full advantage of the new limits..
 */

/* Fixed constants first: */
#undef NR_OPEN
#define NR_OPEN 1024

#define NR_SUPER 64
#define BLOCK_SIZE 1024
#define BLOCK_SIZE_BITS 10

/* And dynamically-tunable limits and defaults: */
extern int max_inodes;
extern int max_files, nr_files;
#define NR_INODE 4096	/* this should be bigger than NR_FILE */
#define NR_FILE 1024	/* this can well be larger on a larger system */

#define MAY_EXEC 1
#define MAY_WRITE 2
#define MAY_READ 4

#define FMODE_READ 1
#define FMODE_WRITE 2

#define READ 0
#define WRITE 1
#define READA 2		/* read-ahead  - don't block if no resources */
#define WRITEA 3	/* write-ahead - don't block if no resources */

#ifndef NULL
#define NULL ((void *) 0)
#endif

#define NIL_FILP	((struct file *)0)
#define SEL_IN		1
#define SEL_OUT		2
#define SEL_EX		4

/* public flags for file_system_type */
#define FS_REQUIRES_DEV 1 
#define FS_NO_DCACHE    2 /* Only dcache the necessary things. */
#define FS_NO_PRELIM    4 /* prevent preloading of dentries, even if
			   * FS_NO_DCACHE is not set.
			   */
#define FS_IBASKET      8 /* FS does callback to free_ibasket() if space gets low. */

/* public flags for i_status */
#define ST_MODIFIED 1024

/*
 * These are the fs-independent mount-flags: up to 16 flags are supported
 */
#define MS_RDONLY	 1	/* Mount read-only */
#define MS_NOSUID	 2	/* Ignore suid and sgid bits */
#define MS_NODEV	 4	/* Disallow access to device special files */
#define MS_NOEXEC	 8	/* Disallow program execution */
#define MS_SYNCHRONOUS	16	/* Writes are synced at once */
#define MS_REMOUNT	32	/* Alter flags of a mounted FS */
#define MS_MANDLOCK	64	/* Allow mandatory locks on an FS */
#define S_WRITE		128	/* Write on file/directory/symlink */
#define S_APPEND	256	/* Append-only file */
#define S_IMMUTABLE	512	/* Immutable file */
#define MS_NOATIME	1024	/* Do not update access times. */

/*
 * Flags that can be altered by MS_REMOUNT
 */
#define MS_RMT_MASK (MS_RDONLY|MS_MANDLOCK)

/*
 * Magic mount flag number. Has to be or-ed to the flag values.
 */
#define MS_MGC_VAL 0xC0ED0000	/* magic flag number to indicate "new" flags */
#define MS_MGC_MSK 0xffff0000	/* magic flag number mask */

/*
 * Public flags for namei()
 */
#define NAM_PLAIN		0 /* Retrieve last component of pathname as is. */
#define NAM_FOLLOW_LINK		2 /* If last component of path is a symlink, follow it */
#define NAM_FOLLOW_TRAILSLASH	4 /* Follow last symlink only if trailed by slash. */

/*
 * Note that read-only etc flags are inode-specific: setting some file-system
 * flags just means all the inodes inherit those flags by default. It might be
 * possible to override it selectively if you really wanted to with some
 * ioctl() that is not currently implemented.
 *
 * Exception: MS_RDONLY is always applied to the entire file system.
 */
#define IS_RDONLY(inode) (((inode)->i_sb) && ((inode)->i_sb->s_flags & MS_RDONLY))
#define IS_NOSUID(inode) ((inode)->i_flags & MS_NOSUID)
#define IS_NODEV(inode) ((inode)->i_flags & MS_NODEV)
#define IS_NOEXEC(inode) ((inode)->i_flags & MS_NOEXEC)
#define IS_SYNC(inode) ((inode)->i_flags & MS_SYNCHRONOUS)
#define IS_MANDLOCK(inode) ((inode)->i_flags & MS_MANDLOCK)

#define IS_WRITABLE(inode) ((inode)->i_flags & S_WRITE)
#define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
#define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
#define IS_NOATIME(inode) ((inode)->i_flags & MS_NOATIME)
#define DO_UPDATE_ATIME(inode) (!IS_NOATIME(inode) && !IS_RDONLY(inode))

/* the read-only stuff doesn't really belong here, but any other place is
   probably as bad and I don't want to create yet another include file. */

#define BLKROSET   _IO(0x12,93)	/* set device read-only (0 = read-write) */
#define BLKROGET   _IO(0x12,94)	/* get read-only status (0 = read_write) */
#define BLKRRPART  _IO(0x12,95)	/* re-read partition table */
#define BLKGETSIZE _IO(0x12,96)	/* return device size */
#define BLKFLSBUF  _IO(0x12,97)	/* flush buffer cache */
#define BLKRASET   _IO(0x12,98)	/* Set read ahead for block device */
#define BLKRAGET   _IO(0x12,99)	/* get current read ahead setting */

#define BMAP_IOCTL 1		/* obsolete - kept for compatibility */
#define FIBMAP	   _IO(0x00,1)	/* bmap access */
#define FIGETBSZ   _IO(0x00,2)	/* get the block size used for bmap */

#ifdef __KERNEL__

#include <asm/semaphore.h>
#include <asm/byteorder.h>
#include <asm/bitops.h>

extern void buffer_init(void);
extern void inode_init(void);
extern void file_table_init(void);
extern unsigned long name_cache_init(unsigned long start, unsigned long end);

typedef char buffer_block[BLOCK_SIZE];

/* bh state bits */
#define BH_Uptodate	0	/* 1 if the buffer contains valid data */
#define BH_Dirty	1	/* 1 if the buffer is dirty */
#define BH_Lock		2	/* 1 if the buffer is locked */
#define BH_Req		3	/* 0 if the buffer has been invalidated */
#define BH_Touched	4	/* 1 if the buffer has been touched (aging) */
#define BH_Has_aged	5	/* 1 if the buffer has been aged (aging) */
#define BH_Protected	6	/* 1 if the buffer is protected */
#define BH_FreeOnIO	7	/* 1 to discard the buffer_head after IO */

/*
 * Try to keep the most commonly used fields in single cache lines (16
 * bytes) to improve performance.  This ordering should be
 * particularly beneficial on 32-bit processors.
 * 
 * We use the first 16 bytes for the data which is used in searches
 * over the block hash lists (ie. getblk(), find_buffer() and
 * friends).
 * 
 * The second 16 bytes we use for lru buffer scans, as used by
 * sync_buffers() and refill_freelist().  -- sct
 */
struct buffer_head {
	/* First cache line: */
	unsigned long b_blocknr;	/* block number */
	kdev_t b_dev;			/* device (B_FREE = free) */
	kdev_t b_rdev;			/* Real device */
	unsigned long b_rsector;	/* Real buffer location on disk */
	struct buffer_head * b_next;	/* Hash queue list */
	struct buffer_head * b_this_page;	/* circular list of buffers in one page */

	/* Second cache line: */
	unsigned long b_state;		/* buffer state bitmap (see above) */
	struct buffer_head * b_next_free;
	unsigned int b_count;		/* users using this block */
	unsigned long b_size;		/* block size */

	/* Non-performance-critical data follows. */
	char * b_data;			/* pointer to data block (1024 bytes) */
	unsigned int b_list;		/* List that this buffer appears */
	unsigned long b_flushtime;      /* Time when this (dirty) buffer
					 * should be written */
	unsigned long b_lru_time;       /* Time when this buffer was 
					 * last used. */
	struct wait_queue * b_wait;
	struct buffer_head ** b_pprev;		/* doubly linked list of hash-queue */
	struct buffer_head * b_prev_free;	/* doubly linked list of buffers */
	struct buffer_head * b_reqnext;		/* request queue */
};

static inline int buffer_uptodate(struct buffer_head * bh)
{
	return test_bit(BH_Uptodate, &bh->b_state);
}	

static inline int buffer_dirty(struct buffer_head * bh)
{
	return test_bit(BH_Dirty, &bh->b_state);
}

static inline int buffer_locked(struct buffer_head * bh)
{
	return test_bit(BH_Lock, &bh->b_state);
}

static inline int buffer_req(struct buffer_head * bh)
{
	return test_bit(BH_Req, &bh->b_state);
}

static inline int buffer_touched(struct buffer_head * bh)
{
	return test_bit(BH_Touched, &bh->b_state);
}

static inline int buffer_has_aged(struct buffer_head * bh)
{
	return test_bit(BH_Has_aged, &bh->b_state);
}

static inline int buffer_protected(struct buffer_head * bh)
{
	return test_bit(BH_Protected, &bh->b_state);
}

#include <linux/pipe_fs_i.h>
#include <linux/minix_fs_i.h>
#include <linux/ext2_fs_i.h>
#include <linux/hpfs_fs_i.h>
#include <linux/msdos_fs_i.h>
#include <linux/umsdos_fs_i.h>
#include <linux/iso_fs_i.h>
#include <linux/nfs_fs_i.h>
#include <linux/sysv_fs_i.h>
#include <linux/affs_fs_i.h>
#include <linux/ufs_fs_i.h>
#include <linux/romfs_fs_i.h>

/*
 * Attribute flags.  These should be or-ed together to figure out what
 * has been changed!
 */
#define ATTR_MODE	1
#define ATTR_UID	2
#define ATTR_GID	4
#define ATTR_SIZE	8
#define ATTR_ATIME	16
#define ATTR_MTIME	32
#define ATTR_CTIME	64
#define ATTR_ATIME_SET	128
#define ATTR_MTIME_SET	256
#define ATTR_FORCE	512	/* Not a change, but a change it */
#define ATTR_ATTR_FLAG	1024

/*
 * This is the Inode Attributes structure, used for notify_change().  It
 * uses the above definitions as flags, to know which values have changed.
 * Also, in this manner, a Filesystem can look at only the values it cares
 * about.  Basically, these are the attributes that the VFS layer can
 * request to change from the FS layer.
 *
 * Derek Atkins <warlord@MIT.EDU> 94-10-20
 */
struct iattr {
	unsigned int	ia_valid;
	umode_t		ia_mode;
	uid_t		ia_uid;
	gid_t		ia_gid;
	off_t		ia_size;
	time_t		ia_atime;
	time_t		ia_mtime;
	time_t		ia_ctime;
	unsigned int	ia_attr_flags;
};

/*
 * This is the inode attributes flag definitions
 */
#define ATTR_FLAG_SYNCRONOUS	1 	/* Syncronous write */
#define ATTR_FLAG_NOATIME	2 	/* Don't update atime */
#define ATTR_FLAG_APPEND	4 	/* Append-only file */
#define ATTR_FLAG_IMMUTABLE	8 	/* Immutable file */

#include <linux/quota.h>

struct inode {
	struct inode 		*i_hash_next;
	struct inode		*i_hash_prev;
	struct inode		*i_next;
	struct inode		*i_prev;

	unsigned long		i_ino;
	kdev_t			i_dev;
	atomic_t		i_count;
	umode_t			i_mode;
	nlink_t			i_nlink;
	uid_t			i_uid;
	gid_t			i_gid;
	kdev_t			i_rdev;
	off_t			i_size;
	time_t			i_atime;
	time_t			i_mtime;
	time_t			i_ctime;
	unsigned long		i_blksize;
	unsigned long		i_blocks;
	unsigned long		i_version;
	unsigned long		i_nrpages;
	struct semaphore	i_sem;
	struct inode_operations	*i_op;
	struct super_block	*i_sb;
	struct wait_queue	*i_wait;
	struct file_lock	*i_flock;
	struct vm_area_struct	*i_mmap;
	struct page		*i_pages;
	struct dquot		*i_dquot[MAXQUOTAS];

	struct inode		*i_lru_next;
	struct inode		*i_lru_prev;

	struct inode		*i_basket_next;
	struct inode		*i_basket_prev;
	struct dentry		*i_dentry;

	short			i_ddir_count;
	short			i_dent_count;
	unsigned short		i_status;
	unsigned short		i_reuse_count;

	struct inode		*i_mount;
	unsigned int		i_flags;
	unsigned char		i_lock;
	unsigned char		i_dirt;
	unsigned char		i_pipe;
	unsigned char		i_sock;

	unsigned char		i_level;
	unsigned short		i_fill;

	int			i_writecount;
	unsigned int		i_attr_flags;
	union {
		struct pipe_inode_info		pipe_i;
		struct minix_inode_info		minix_i;
		struct ext2_inode_info		ext2_i;
		struct hpfs_inode_info		hpfs_i;
		struct msdos_inode_info		msdos_i;
		struct umsdos_inode_info	umsdos_i;
		struct iso_inode_info		isofs_i;
		struct nfs_inode_info		nfs_i;
		struct sysv_inode_info		sysv_i;
		struct affs_inode_info		affs_i;
		struct ufs_inode_info		ufs_i;
		struct romfs_inode_info		romfs_i;
		struct socket			socket_i;
		void				*generic_ip;
	} u;
};

struct file {
	struct file		*f_next, **f_pprev;
	struct inode		*f_inode;
	struct file_operations	*f_op;
	mode_t			f_mode;
	loff_t			f_pos;
	unsigned short 		f_count, f_flags;
	unsigned long 		f_reada, f_ramax, f_raend, f_ralen, f_rawin;

	/* pid or -pgrp where SIGIO should be sent */
	int 			f_owner;

	unsigned long		f_version;

	/* needed for tty driver, and maybe others */
	void			*private_data;
};

#define FL_POSIX	1
#define FL_FLOCK	2
#define FL_BROKEN	4	/* broken flock() emulation */
#define FL_ACCESS	8	/* for processes suspended by mandatory locking */
#define FL_LOCKD	16	/* lock held by rpc.lockd */

struct file_lock {
	struct file_lock *fl_next;	/* singly linked list for this inode  */
	struct file_lock *fl_nextlink;	/* doubly linked list of all locks */
	struct file_lock *fl_prevlink;	/* used to simplify lock removal */
	struct file_lock *fl_nextblock; /* circular list of blocked processes */
	struct file_lock *fl_prevblock;
	void *fl_owner;			/* usu. the process' task_struct */
	unsigned int fl_pid;
	struct wait_queue *fl_wait;
	struct file *fl_file;
	unsigned char fl_flags;
	unsigned char fl_type;
	off_t fl_start;
	off_t fl_end;

	void (*fl_notify)(struct file_lock *);	/* unblock callback */

	union {
		struct nfs_lock_info	nfs_fl;
	} fl_u;
};

extern struct file_lock		*file_lock_table;

#include <linux/fcntl.h>

extern int fcntl_getlk(unsigned int fd, struct flock *l);
extern int fcntl_setlk(unsigned int fd, unsigned int cmd, struct flock *l);
extern void locks_remove_locks(struct task_struct *task, struct file *filp);
extern struct file_lock *posix_test_lock(struct file *, struct file_lock *);
extern int posix_lock_file(struct file *, struct file_lock *, unsigned int);
extern void posix_block_lock(struct file_lock *, struct file_lock *);
extern void posix_unblock_lock(struct file_lock *);

#include <linux/stat.h>

#define FLOCK_VERIFY_READ  1
#define FLOCK_VERIFY_WRITE 2

extern int locks_mandatory_locked(struct inode *inode);
extern int locks_mandatory_area(int read_write, struct inode *inode,
				struct file *filp, unsigned int offset,
				unsigned int count);

extern inline int locks_verify_locked(struct inode *inode)
{
	/* Candidates for mandatory locking have the setgid bit set
	 * but no group execute bit -  an otherwise meaningless combination.
	 */
	if (IS_MANDLOCK(inode) &&
	    (inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
		return (locks_mandatory_locked(inode));
	return (0);
}
extern inline int locks_verify_area(int read_write, struct inode *inode,
				    struct file *filp, unsigned int offset,
				    unsigned int count)
{
	/* Candidates for mandatory locking have the setgid bit set
	 * but no group execute bit -  an otherwise meaningless combination.
	 */
	if (IS_MANDLOCK(inode) &&
	    (inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
		return (locks_mandatory_area(read_write, inode, filp, offset,
					     count));
	return (0);
}

struct fasync_struct {
	int    magic;
	struct fasync_struct	*fa_next; /* singly linked list */
	struct file 		*fa_file;
};

#define FASYNC_MAGIC 0x4601

extern int fasync_helper(struct inode *, struct file *, int, struct fasync_struct **);

#include <linux/minix_fs_sb.h>
#include <linux/ext2_fs_sb.h>
#include <linux/hpfs_fs_sb.h>
#include <linux/msdos_fs_sb.h>
#include <linux/iso_fs_sb.h>
#include <linux/nfs_fs_sb.h>
#include <linux/sysv_fs_sb.h>
#include <linux/affs_fs_sb.h>
#include <linux/ufs_fs_sb.h>
#include <linux/romfs_fs_sb.h>

struct super_block {
	kdev_t			s_dev;
	unsigned long		s_blocksize;
	unsigned char		s_blocksize_bits;
	unsigned char		s_lock;
	unsigned char		s_rd_only;
	unsigned char		s_dirt;
	struct file_system_type	*s_type;
	struct super_operations	*s_op;
	struct dquot_operations	*dq_op;
	unsigned long		s_flags;
	unsigned long		s_magic;
	unsigned long		s_time;
	struct inode		*s_covered;
	struct inode		*s_mounted;
	struct wait_queue	*s_wait;

	struct inode		*s_ibasket;
	short int		s_ibasket_count;
	short int		s_ibasket_max;

	union {
		struct minix_sb_info	minix_sb;
		struct ext2_sb_info	ext2_sb;
		struct hpfs_sb_info	hpfs_sb;
		struct msdos_sb_info	msdos_sb;
		struct isofs_sb_info	isofs_sb;
		struct nfs_sb_info	nfs_sb;
		struct sysv_sb_info	sysv_sb;
		struct affs_sb_info	affs_sb;
		struct ufs_sb_info	ufs_sb;
		struct romfs_sb_info	romfs_sb;
		void			*generic_sbp;
	} u;
};

/*
 * This is the "filldir" function type, used by readdir() to let
 * the kernel specify what kind of dirent layout it wants to have.
 * This allows the kernel to read directories into kernel space or
 * to have different dirent layouts depending on the binary type.
 */
typedef int (*filldir_t)(void *, const char *, int, off_t, ino_t);
	
struct file_operations {
	long long (*llseek) (struct inode *, struct file *, long long, int);
	long (*read) (struct inode *, struct file *, char *, unsigned long);
	long (*write) (struct inode *, struct file *, const char *, unsigned long);
	int (*readdir) (struct inode *, struct file *, void *, filldir_t);
	unsigned int (*poll) (struct file *, poll_table *);
	int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
	int (*mmap) (struct inode *, struct file *, struct vm_area_struct *);
	int (*open) (struct inode *, struct file *);
	int (*release) (struct inode *, struct file *);
	int (*fsync) (struct inode *, struct file *);
	int (*fasync) (struct inode *, struct file *, int);
	int (*check_media_change) (kdev_t dev);
	int (*revalidate) (kdev_t dev);
	int (*lock) (struct inode *, struct file *, int, struct file_lock *);
};

struct inode_operations {
	struct file_operations * default_file_ops;
	int (*create) (struct inode *,const char *,int,int,struct inode **);
	int (*lookup) (struct inode *,const char *,int,struct inode **);
	int (*link) (struct inode *,struct inode *,const char *,int);
	int (*unlink) (struct inode *,const char *,int);
	int (*symlink) (struct inode *,const char *,int,const char *);
	int (*mkdir) (struct inode *,const char *,int,int);
	int (*rmdir) (struct inode *,const char *,int);
	int (*mknod) (struct inode *,const char *,int,int,int);
	int (*rename) (struct inode *,const char *,int,struct inode *,const char *,int);
	int (*readlink) (struct inode *,char *,int);
	int (*readpage) (struct inode *, struct page *);
	int (*writepage) (struct inode *, struct page *);
	int (*bmap) (struct inode *,int);
	void (*truncate) (struct inode *);
	int (*permission) (struct inode *, int);
	int (*smap) (struct inode *,int);
	int (*updatepage) (struct inode *, struct page *, const char *,
				unsigned long, unsigned int, int);
	int (*revalidate) (struct inode *);
};

struct super_operations {
	void (*read_inode) (struct inode *);
	int (*notify_change) (struct inode *, struct iattr *);
	void (*write_inode) (struct inode *);
	void (*put_inode) (struct inode *);
	void (*put_super) (struct super_block *);
	void (*write_super) (struct super_block *);
	void (*statfs) (struct super_block *, struct statfs *, int);
	int (*remount_fs) (struct super_block *, int *, char *);
};

struct dquot_operations {
	void (*initialize) (struct inode *, short);
	void (*drop) (struct inode *);
	int (*alloc_block) (const struct inode *, unsigned long);
	int (*alloc_inode) (const struct inode *, unsigned long);
	void (*free_block) (const struct inode *, unsigned long);
	void (*free_inode) (const struct inode *, unsigned long);
	int (*transfer) (struct inode *, struct iattr *, char);
};

struct file_system_type {
	const char *name;
	int fs_flags;
	struct super_block *(*read_super) (struct super_block *, void *, int);
	struct file_system_type * next;
};

extern int register_filesystem(struct file_system_type *);
extern int unregister_filesystem(struct file_system_type *);

asmlinkage int sys_open(const char *, int, int);
asmlinkage int sys_close(unsigned int);		/* yes, it's really unsigned */

extern void kill_fasync(struct fasync_struct *fa, int sig);

extern int getname(const char * filename, char **result);
extern void putname(char * name);
extern int do_truncate(struct inode *, unsigned long);
extern int register_blkdev(unsigned int, const char *, struct file_operations *);
extern int unregister_blkdev(unsigned int major, const char * name);
extern int blkdev_open(struct inode * inode, struct file * filp);
extern int blkdev_release (struct inode * inode);
extern struct file_operations def_blk_fops;
extern struct inode_operations blkdev_inode_operations;

extern int register_chrdev(unsigned int, const char *, struct file_operations *);
extern int unregister_chrdev(unsigned int major, const char * name);
extern int chrdev_open(struct inode * inode, struct file * filp);
extern struct file_operations def_chr_fops;
extern struct inode_operations chrdev_inode_operations;

extern void init_fifo(struct inode * inode);
extern struct inode_operations fifo_inode_operations;

extern struct file_operations connecting_fifo_fops;
extern struct file_operations read_fifo_fops;
extern struct file_operations write_fifo_fops;
extern struct file_operations rdwr_fifo_fops;
extern struct file_operations read_pipe_fops;
extern struct file_operations write_pipe_fops;
extern struct file_operations rdwr_pipe_fops;

extern struct file_system_type *get_fs_type(const char *name);

extern int fs_may_mount(kdev_t dev);
extern int fs_may_umount(kdev_t dev, struct inode * mount_root);
extern int fs_may_remount_ro(kdev_t dev);

extern struct file *inuse_filps;
extern struct super_block super_blocks[NR_SUPER];

extern void refile_buffer(struct buffer_head * buf);
extern void set_writetime(struct buffer_head * buf, int flag);
extern int try_to_free_buffer(struct buffer_head*, struct buffer_head**, int);

extern int nr_buffers;
extern int buffermem;
extern int nr_buffer_heads;

#define BUF_CLEAN	0
#define BUF_LOCKED	1	/* Buffers scheduled for write */
#define BUF_DIRTY	2	/* Dirty buffers, not yet scheduled for write */
#define NR_LIST		3

void mark_buffer_uptodate(struct buffer_head * bh, int on);

extern inline void mark_buffer_clean(struct buffer_head * bh)
{
	if (test_and_clear_bit(BH_Dirty, &bh->b_state)) {
		if (bh->b_list == BUF_DIRTY)
			refile_buffer(bh);
	}
}

extern inline void mark_buffer_dirty(struct buffer_head * bh, int flag)
{
	if (!test_and_set_bit(BH_Dirty, &bh->b_state)) {
		set_writetime(bh, flag);
		if (bh->b_list != BUF_DIRTY)
			refile_buffer(bh);
	}
}

extern int check_disk_change(kdev_t dev);
extern void invalidate_inodes(kdev_t dev);
extern void invalidate_inode_pages(struct inode *);
extern void invalidate_buffers(kdev_t dev);
extern int floppy_is_wp(int minor);
extern void sync_inodes(kdev_t dev);
extern void sync_dev(kdev_t dev);
extern int fsync_dev(kdev_t dev);
extern void sync_supers(kdev_t dev);
extern int bmap(struct inode * inode,int block);
extern int notify_change(struct inode *, struct iattr *);
extern int namei(int retr_mode, const char *pathname, struct inode **res_inode);
extern int permission(struct inode * inode,int mask);
extern int get_write_access(struct inode *inode);
extern void put_write_access(struct inode *inode);
extern int open_namei(const char * pathname, int flag, int mode,
	struct inode ** res_inode, struct inode * base);
extern int do_mknod(const char * filename, int mode, dev_t dev);
extern int do_pipe(int *);

#include <asm/semaphore.h>

/* Intended for short locks of the global data structures in inode.c.
 * Could be replaced with spinlocks completely, since there is
 * no blocking during manipulation of the static data; however the
 * lock in invalidate_inodes() may last relatively long.
 */
extern struct semaphore vfs_sem;
extern inline void vfs_lock(void)
{
#if 0
#ifdef __SMP__
	down(&vfs_sem);
#endif
#endif
}

extern inline void vfs_unlock(void)
{
#if 0
#ifdef __SMP__
	up(&vfs_sem);
#endif
#endif
}

/* Not to be used by ordinary vfs users */
extern void _get_inode(struct inode * inode);
extern blocking void __iput(struct inode * inode);

/* This must not be called if the inode is not in use (i.e. given
 * back with iput(). The atomic inc assumes that the inode is
 * already in use, and just has to be incremented higher. 
 * Please do not directly manipulate i_count any more.
 * Use iget, iinc and iput.
 * You may test i_count for zero if you are aware that it
 * might change under you.
 */
extern inline void iinc(struct inode * inode)
{
	atomic_inc(&inode->i_count);
}

/* The same, but the inode may not be in use. This must be called
 * with vfslock() held, and be asure that the inode argument is
 * valid (i.e. not out of cache). So the vfs_lock() must span the
 * retrieval method of the inode.
 */
extern inline void iinc_zero(struct inode * inode)
{
	if(!atomic_read(&inode->i_count)) {
		atomic_inc(&inode->i_count);
		_get_inode(inode);
	} else
		atomic_inc(&inode->i_count);
}

extern blocking void _iput(struct inode * inode);
extern inline blocking void iput(struct inode * inode)
{
	if(inode) {
		extern void wake_up_interruptible(struct wait_queue **q);

		if(inode->i_pipe)
			wake_up_interruptible(&inode->u.pipe_i.wait);

		/* It does not matter if somebody re-increments it in between,
		 * only the _last_ user needs to call _iput().
		 */
		if(atomic_dec_and_test(&inode->i_count) && inode->i_ddir_count <= 0)
			_iput(inode);
	}
}

extern blocking struct inode * __iget(struct super_block * sb, unsigned long nr, int crsmnt);
extern blocking void _clear_inode(struct inode * inode, int external, int verbose);
extern blocking inline void clear_inode(struct inode * inode)
{
	vfs_lock();
	_clear_inode(inode, 1, 1);
	vfs_unlock();
}
extern blocking struct inode * _get_empty_inode(void);
extern inline blocking struct inode * get_empty_inode(void)
{
	struct inode * inode;
	vfs_lock();
	inode = _get_empty_inode();
	vfs_unlock();
	return inode;
}
/* Please prefer to use this function in future, instead of using
 * a get_empty_inode()/insert_inode_hash() combination.
 * It allows for better checking and less race conditions.
 */
blocking struct inode * get_empty_inode_hashed(dev_t i_dev, unsigned long i_ino);

extern inline blocking int free_ibasket(struct super_block * sb)
{
	extern blocking int _free_ibasket(struct super_block * sb);
	int res;
	vfs_lock();
	res = _free_ibasket(sb);
	vfs_unlock();
	return res;
}

extern void insert_inode_hash(struct inode *);
extern blocking struct inode * get_pipe_inode(void);
extern int get_unused_fd(void);
extern void put_unused_fd(int);
extern struct file * get_empty_filp(void);
extern int close_fp(struct file *filp);
extern struct buffer_head * get_hash_table(kdev_t dev, int block, int size);
extern struct buffer_head * getblk(kdev_t dev, int block, int size);
extern void ll_rw_block(int rw, int nr, struct buffer_head * bh[]);
extern void ll_rw_page(int rw, kdev_t dev, unsigned long nr, char * buffer);
extern void ll_rw_swap_file(int rw, kdev_t dev, unsigned int *b, int nb, char *buffer);
extern int is_read_only(kdev_t dev);
extern void __brelse(struct buffer_head *buf);
extern inline void brelse(struct buffer_head *buf)
{
	if (buf)
		__brelse(buf);
}
extern void __bforget(struct buffer_head *buf);
extern inline void bforget(struct buffer_head *buf)
{
	if (buf)
		__bforget(buf);
}
extern void set_blocksize(kdev_t dev, int size);
extern unsigned int get_hardblocksize(kdev_t dev);
extern struct buffer_head * bread(kdev_t dev, int block, int size);
extern struct buffer_head * breada(kdev_t dev,int block, int size, 
				   unsigned int pos, unsigned int filesize);

extern int brw_page(int, struct page *, kdev_t, int [], int, int);

extern int generic_readpage(struct inode *, struct page *);
extern int generic_file_mmap(struct inode *, struct file *, struct vm_area_struct *);
extern long generic_file_read(struct inode *, struct file *, char *, unsigned long);
extern long generic_file_write(struct inode *, struct file *, const char *, unsigned long);

extern struct super_block *get_super(kdev_t dev);
extern void put_super(kdev_t dev);
unsigned long generate_cluster(kdev_t dev, int b[], int size);
unsigned long generate_cluster_swab32(kdev_t dev, int b[], int size);
extern kdev_t ROOT_DEV;

extern void show_buffers(void);
extern void mount_root(void);

#ifdef CONFIG_BLK_DEV_INITRD
extern kdev_t real_root_dev;
extern int change_root(kdev_t new_root_dev,const char *put_old);
#endif

extern long char_read(struct inode *, struct file *, char *, unsigned long);
extern long block_read(struct inode *, struct file *, char *, unsigned long);
extern int read_ahead[];

extern long char_write(struct inode *, struct file *, const char *, unsigned long);
extern long block_write(struct inode *, struct file *, const char *, unsigned long);

extern int block_fsync(struct inode *, struct file *);
extern int file_fsync(struct inode *, struct file *);

extern void dcache_add(struct inode *, const char *, int, unsigned long);
extern int dcache_lookup(struct inode *, const char *, int, unsigned long *);

extern int inode_change_ok(struct inode *, struct iattr *);
extern void inode_setattr(struct inode *, struct iattr *);

extern inline blocking 
struct inode * iget(struct super_block * sb, unsigned long nr)
{
	return __iget(sb, nr, 1);
}

/* kludge to get SCSI modules working */
#include <linux/minix_fs.h>
#include <linux/minix_fs_sb.h>

#endif /* __KERNEL__ */

#endif