fs.h

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	int (*sync_page)(struct page *);
	int (*prepare_write)(struct file *, struct page *, unsigned, unsigned);
	int (*commit_write)(struct file *, struct page *, unsigned, unsigned);
	/* Unfortunately this kludge is needed for FIBMAP. Don't use it */
	int (*bmap)(struct address_space *, long);
};

struct address_space {
	struct list_head	clean_pages;	/* list of clean pages */
	struct list_head	dirty_pages;	/* list of dirty pages */
	struct list_head	locked_pages;	/* list of locked pages */
	unsigned long		nrpages;	/* number of total pages */
	struct address_space_operations *a_ops;	/* methods */
	struct inode		*host;		/* owner: inode, block_device */
	struct vm_area_struct	*i_mmap;	/* list of private mappings */
	struct vm_area_struct	*i_mmap_shared; /* list of shared mappings */
	spinlock_t		i_shared_lock;  /* and spinlock protecting it */
};

struct block_device {
	struct list_head	bd_hash;
	atomic_t		bd_count;
/*	struct address_space	bd_data; */
	dev_t			bd_dev;  /* not a kdev_t - it's a search key */
	atomic_t		bd_openers;
	const struct block_device_operations *bd_op;
	struct semaphore	bd_sem;	/* open/close mutex */
};

struct inode {
	struct list_head	i_hash;
	struct list_head	i_list;
	struct list_head	i_dentry;
	
	struct list_head	i_dirty_buffers;

	unsigned long		i_ino;
	atomic_t		i_count;
	kdev_t			i_dev;
	umode_t			i_mode;
	nlink_t			i_nlink;
	uid_t			i_uid;
	gid_t			i_gid;
	kdev_t			i_rdev;
	loff_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;
	struct semaphore	i_sem;
	struct semaphore	i_zombie;
	struct inode_operations	*i_op;
	struct file_operations	*i_fop;	/* former ->i_op->default_file_ops */
	struct super_block	*i_sb;
	wait_queue_head_t	i_wait;
	struct file_lock	*i_flock;
	struct address_space	*i_mapping;
	struct address_space	i_data;	
	struct dquot		*i_dquot[MAXQUOTAS];
	struct pipe_inode_info	*i_pipe;
	struct block_device	*i_bdev;

	unsigned long		i_dnotify_mask; /* Directory notify events */
	struct dnotify_struct	*i_dnotify; /* for directory notifications */

	unsigned long		i_state;

	unsigned int		i_flags;
	unsigned char		i_sock;

	atomic_t		i_writecount;
	unsigned int		i_attr_flags;
	__u32			i_generation;
	union {
		struct minix_inode_info		minix_i;
		struct ext2_inode_info		ext2_i;
		struct hpfs_inode_info		hpfs_i;
		struct ntfs_inode_info		ntfs_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 efs_inode_info		efs_i;
		struct romfs_inode_info		romfs_i;
		struct shmem_inode_info		shmem_i;
		struct coda_inode_info		coda_i;
		struct smb_inode_info		smbfs_i;
		struct hfs_inode_info		hfs_i;
		struct adfs_inode_info		adfs_i;
		struct qnx4_inode_info		qnx4_i;
		struct bfs_inode_info		bfs_i;
		struct udf_inode_info		udf_i;
		struct ncp_inode_info		ncpfs_i;
		struct proc_inode_info		proc_i;
		struct socket			socket_i;
		struct usbdev_inode_info        usbdev_i;
		void				*generic_ip;
	} u;
};

/* Inode state bits.. */
#define I_DIRTY_SYNC		1 /* Not dirty enough for O_DATASYNC */
#define I_DIRTY_DATASYNC	2 /* Data-related inode changes pending */
#define I_DIRTY_PAGES		4 /* Data-related inode changes pending */
#define I_LOCK			8
#define I_FREEING		16
#define I_CLEAR			32

#define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)

extern void __mark_inode_dirty(struct inode *, int);
static inline void mark_inode_dirty(struct inode *inode)
{
	if ((inode->i_state & I_DIRTY) != I_DIRTY)
		__mark_inode_dirty(inode, I_DIRTY);
}

static inline void mark_inode_dirty_sync(struct inode *inode)
{
	if (!(inode->i_state & I_DIRTY_SYNC))
		__mark_inode_dirty(inode, I_DIRTY_SYNC);
}

static inline void mark_inode_dirty_pages(struct inode *inode)
{
	if (inode && !(inode->i_state & I_DIRTY_PAGES))
		__mark_inode_dirty(inode, I_DIRTY_PAGES);
}

struct fown_struct {
	int pid;		/* pid or -pgrp where SIGIO should be sent */
	uid_t uid, euid;	/* uid/euid of process setting the owner */
	int signum;		/* posix.1b rt signal to be delivered on IO */
};

struct file {
	struct list_head	f_list;
	struct dentry		*f_dentry;
	struct vfsmount         *f_vfsmnt;
	struct file_operations	*f_op;
	atomic_t		f_count;
	unsigned int 		f_flags;
	mode_t			f_mode;
	loff_t			f_pos;
	unsigned long 		f_reada, f_ramax, f_raend, f_ralen, f_rawin;
	struct fown_struct	f_owner;
	unsigned int		f_uid, f_gid;
	int			f_error;

	unsigned long		f_version;

	/* needed for tty driver, and maybe others */
	void			*private_data;
};
extern spinlock_t files_lock;
#define file_list_lock() spin_lock(&files_lock);
#define file_list_unlock() spin_unlock(&files_lock);

#define get_file(x)	atomic_inc(&(x)->f_count)
#define file_count(x)	atomic_read(&(x)->f_count)

extern int init_private_file(struct file *, struct dentry *, int);

#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 */
#define FL_LEASE	32	/* lease held on this file */

/*
 * The POSIX file lock owner is determined by
 * the "struct files_struct" in the thread group
 * (or NULL for no owner - BSD locks).
 *
 * Lockd stuffs a "host" pointer into this.
 */
typedef struct files_struct *fl_owner_t;

struct file_lock {
	struct file_lock *fl_next;	/* singly linked list for this inode  */
	struct list_head fl_link;	/* doubly linked list of all locks */
	struct list_head fl_block;	/* circular list of blocked processes */
	fl_owner_t fl_owner;
	unsigned int fl_pid;
	wait_queue_head_t fl_wait;
	struct file *fl_file;
	unsigned char fl_flags;
	unsigned char fl_type;
	loff_t fl_start;
	loff_t fl_end;

	void (*fl_notify)(struct file_lock *);	/* unblock callback */
	void (*fl_insert)(struct file_lock *);	/* lock insertion callback */
	void (*fl_remove)(struct file_lock *);	/* lock removal callback */

	struct fasync_struct *	fl_fasync; /* for lease break notifications */

	union {
		struct nfs_lock_info	nfs_fl;
	} fl_u;
};

/* The following constant reflects the upper bound of the file/locking space */
#ifndef OFFSET_MAX
#define INT_LIMIT(x)	(~((x)1 << (sizeof(x)*8 - 1)))
#define OFFSET_MAX	INT_LIMIT(loff_t)
#define OFFT_OFFSET_MAX	INT_LIMIT(off_t)
#endif

extern struct list_head file_lock_list;

#include <linux/fcntl.h>

extern int fcntl_getlk(unsigned int, struct flock *);
extern int fcntl_setlk(unsigned int, unsigned int, struct flock *);

extern int fcntl_getlk64(unsigned int, struct flock64 *);
extern int fcntl_setlk64(unsigned int, unsigned int, struct flock64 *);

/* fs/locks.c */
extern void locks_init_lock(struct file_lock *);
extern void locks_copy_lock(struct file_lock *, struct file_lock *);
extern void locks_remove_posix(struct file *, fl_owner_t);
extern void locks_remove_flock(struct file *);
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 *);
extern int __get_lease(struct inode *inode, unsigned int flags);
extern time_t lease_get_mtime(struct inode *);
extern int lock_may_read(struct inode *, loff_t start, unsigned long count);
extern int lock_may_write(struct inode *, loff_t start, unsigned long count);

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

#define FASYNC_MAGIC 0x4601

/* SMP safe fasync helpers: */
extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
/* can be called from interrupts */
extern void kill_fasync(struct fasync_struct **, int, int);
/* only for net: no internal synchronization */
extern void __kill_fasync(struct fasync_struct *, int, int);

struct nameidata {
	struct dentry *dentry;
	struct vfsmount *mnt;
	struct qstr last;
	unsigned int flags;
	int last_type;
};

#define DQUOT_USR_ENABLED	0x01		/* User diskquotas enabled */
#define DQUOT_GRP_ENABLED	0x02		/* Group diskquotas enabled */

struct quota_mount_options
{
	unsigned int flags;			/* Flags for diskquotas on this device */
	struct semaphore dqio_sem;		/* lock device while I/O in progress */
	struct semaphore dqoff_sem;		/* serialize quota_off() and quota_on() on device */
	struct file *files[MAXQUOTAS];		/* fp's to quotafiles */
	time_t inode_expire[MAXQUOTAS];		/* expiretime for inode-quota */
	time_t block_expire[MAXQUOTAS];		/* expiretime for block-quota */
	char rsquash[MAXQUOTAS];		/* for quotas threat root as any other user */
};

/*
 *	Umount options
 */

#define MNT_FORCE	0x00000001	/* Attempt to forcibily umount */

#include <linux/minix_fs_sb.h>
#include <linux/ext2_fs_sb.h>
#include <linux/hpfs_fs_sb.h>
#include <linux/ntfs_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/efs_fs_sb.h>
#include <linux/romfs_fs_sb.h>
#include <linux/smb_fs_sb.h>
#include <linux/hfs_fs_sb.h>
#include <linux/adfs_fs_sb.h>
#include <linux/qnx4_fs_sb.h>
#include <linux/bfs_fs_sb.h>
#include <linux/udf_fs_sb.h>
#include <linux/ncp_fs_sb.h>
#include <linux/usbdev_fs_sb.h>

extern struct list_head super_blocks;

#define sb_entry(list)	list_entry((list), struct super_block, s_list)
struct super_block {
	struct list_head	s_list;		/* Keep this first */
	kdev_t			s_dev;
	unsigned long		s_blocksize;
	unsigned char		s_blocksize_bits;
	unsigned char		s_lock;
	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;
	struct dentry		*s_root;
	wait_queue_head_t	s_wait;

	struct list_head	s_dirty;	/* dirty inodes */
	struct list_head	s_files;

	struct block_device	*s_bdev;
	struct list_head	s_mounts;	/* vfsmount(s) of this one */
	struct quota_mount_options s_dquot;	/* Diskquota specific options */

	union {
		struct minix_sb_info	minix_sb;
		struct ext2_sb_info	ext2_sb;
		struct hpfs_sb_info	hpfs_sb;
		struct ntfs_sb_info	ntfs_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 efs_sb_info	efs_sb;
		struct shmem_sb_info	shmem_sb;
		struct romfs_sb_info	romfs_sb;
		struct smb_sb_info	smbfs_sb;
		struct hfs_sb_info	hfs_sb;
		struct adfs_sb_info	adfs_sb;
		struct qnx4_sb_info	qnx4_sb;
		struct bfs_sb_info	bfs_sb;
		struct udf_sb_info	udf_sb;
		struct ncp_sb_info	ncpfs_sb;
		struct usbdev_sb_info   usbdevfs_sb;
		void			*generic_sbp;
	} u;
	/*
	 * The next field is for VFS *only*. No filesystems have any business
	 * even looking at it. You had been warned.
	 */