/*

* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description: 

*

*/

#ifndef _SYS_FILE_H_

#define	_SYS_FILE_H_

#ifndef _KERNEL

#include <sys/types.h> /* XXX */

#include <sys/fcntl.h>

#include <sys/unistd.h>

#else

#include <sys/queue.h>

#include <sys/_lock.h>

#include <sys/_mutex.h>

struct stat;

struct thread;

struct uio;

struct knote;

struct vnode;

struct socket;

#endif /* _KERNEL */

#define	DTYPE_VNODE	1	/* file */

#define	DTYPE_SOCKET	2	/* communications endpoint */

#define	DTYPE_PIPE	3	/* pipe */

#define	DTYPE_FIFO	4	/* fifo (named pipe) */

#define	DTYPE_KQUEUE	5	/* event queue */

#define	DTYPE_CRYPTO	6	/* crypto */

#ifdef _KERNEL

struct file;

struct ucred;

typedef int fo_rdwr_t(struct file *fp, struct uio *uio,

		    struct ucred *active_cred, int flags,

		    struct thread *td);

#define	FOF_OFFSET	1	/* Use the offset in uio argument */

typedef	int fo_ioctl_t(struct file *fp, u_long com, void *data,

		    struct ucred *active_cred, struct thread *td);

typedef	int fo_poll_t(struct file *fp, int events,

		    struct ucred *active_cred, struct thread *td);

typedef	int fo_kqfilter_t(struct file *fp, struct knote *kn);

typedef	int fo_stat_t(struct file *fp, struct stat *sb,

		    struct ucred *active_cred, struct thread *td);

typedef	int fo_close_t(struct file *fp, struct thread *td);

typedef	int fo_flags_t;

struct fileops {

	fo_rdwr_t	*fo_read;

	fo_rdwr_t	*fo_write;

	fo_ioctl_t	*fo_ioctl;

	fo_poll_t	*fo_poll;

	fo_kqfilter_t	*fo_kqfilter;

	fo_stat_t	*fo_stat;

	fo_close_t	*fo_close;

	fo_flags_t	fo_flags;	/* DFLAG_* below */

};

#define DFLAG_PASSABLE	0x01	/* may be passed via unix sockets. */

#define DFLAG_SEEKABLE	0x02	/* seekable / nonsequential */

/*

 * Kernel descriptor table.

 * One entry for each open kernel vnode and socket.

 *

 * Below is the list of locks that protects members in struct file.

 *

 * (fl)	filelist_lock

 * (f)	f_mtx in struct file

 * none	not locked

 */

struct file {

	LIST_ENTRY(file) f_list;/* (fl) list of active files */

	short	f_type;		/* descriptor type */

	void	*f_data;	/* file descriptor specific data */

	u_int	f_flag;		/* see fcntl.h */

	struct mtx	*f_mtxp;	/* mutex to protect data */

	struct fileops *f_ops;	/* File operations */

	struct	ucred *f_cred;	/* credentials associated with descriptor */

	int	f_count;	/* (f) reference count */

	struct vnode *f_vnode;	/* NULL or applicable vnode */

	/* DFLAG_SEEKABLE specific fields */

	off_t	f_offset;

	/* DTYPE_SOCKET specific fields */

	short	f_gcflag;	/* used by thread doing fd garbage collection */

#define	FMARK		0x1	/* mark during gc() */

#define	FDEFER		0x2	/* defer for next gc pass */

	int	f_msgcount;	/* (f) references from message queue */

	/* DTYPE_VNODE specific fields */

	int	f_seqcount;	/*

				 * count of sequential accesses -- cleared

				 * by most seek operations.

				 */

	off_t	f_nextoff;	/*

				 * offset of next expected read or write

				 */

	void	*f_label;	/* Place-holder for struct label pointer. */

};

#endif /* _KERNEL */

/*

 * Userland version of struct file, for sysctl

 */

struct xfile {

	size_t	xf_size;	/* size of struct xfile */

	pid_t	xf_pid;		/* owning process */

	uid_t	xf_uid;		/* effective uid of owning process */

	int	xf_fd;		/* descriptor number */

	void	*xf_file;	/* address of struct file */

	short	xf_type;	/* descriptor type */

	int	xf_count;	/* reference count */

	int	xf_msgcount;	/* references from message queue */

	off_t	xf_offset;	/* file offset */

	void	*xf_data;	/* file descriptor specific data */

	void	*xf_vnode;	/* vnode pointer */

	u_int	xf_flag;	/* flags (see fcntl.h) */

};

#ifdef _KERNEL

extern struct filelist filehead; /* (fl) head of list of open files */

extern struct fileops vnops;

extern struct fileops badfileops;

extern struct fileops socketops;

extern int maxfiles;		/* kernel limit on number of open files */

extern int maxfilesperproc;	/* per process limit on number of open files */

extern int openfiles;		/* (fl) actual number of open files */

extern struct sx filelist_lock; /* sx to protect filelist and openfiles */

/*

 * The socket operations are used a couple of places.

 * XXX: This is wrong, they should go through the operations vector for

 * XXX: sockets instead of going directly for the individual functions. /phk

 */

fo_rdwr_t	soo_read;

fo_rdwr_t	soo_write;

fo_ioctl_t	soo_ioctl;

fo_poll_t	soo_poll;

fo_kqfilter_t	soo_kqfilter;

fo_stat_t	soo_stat;

fo_close_t	soo_close;

/* Lock a file. */

#define	FILE_LOCK(f)	mtx_lock((f)->f_mtxp)

#define	FILE_UNLOCK(f)	mtx_unlock((f)->f_mtxp)

#define	FILE_LOCKED(f)	mtx_owned((f)->f_mtxp)

#define	FILE_LOCK_ASSERT(f, type) mtx_assert((f)->f_mtxp, (type))

#define	fhold_locked(fp)						\

	do {								\

		FILE_LOCK_ASSERT(fp, MA_OWNED);				\

		(fp)->f_count++;					\

	} while (0)

#define	fhold(fp)							\

	do {								\

		FILE_LOCK(fp);						\

		(fp)->f_count++;					\

		FILE_UNLOCK(fp);					\

	} while (0)

static __inline fo_rdwr_t	fo_read;

static __inline fo_rdwr_t	fo_write;

static __inline fo_ioctl_t	fo_ioctl;

static __inline fo_poll_t	fo_poll;

static __inline fo_kqfilter_t	fo_kqfilter;

static __inline fo_stat_t	fo_stat;

static __inline fo_close_t	fo_close;

static __inline int

fo_read(fp, uio, active_cred, flags, td)

	struct file *fp;

	struct uio *uio;

	struct ucred *active_cred;

	int flags;

	struct thread *td;

{

	return ((*fp->f_ops->fo_read)(fp, uio, active_cred, flags, td));

}

static __inline int

fo_write(fp, uio, active_cred, flags, td)

	struct file *fp;

	struct uio *uio;

	struct ucred *active_cred;

	int flags;

	struct thread *td;

{

	return ((*fp->f_ops->fo_write)(fp, uio, active_cred, flags, td));

}

static __inline int

fo_ioctl(fp, com, data, active_cred, td)

	struct file *fp;

	u_long com;

	void *data;

	struct ucred *active_cred;

	struct thread *td;

{

	return ((*fp->f_ops->fo_ioctl)(fp, com, data, active_cred, td));

}

static __inline int

fo_poll(fp, events, active_cred, td)

	struct file *fp;

	int events;

	struct ucred *active_cred;

	struct thread *td;

{

	return ((*fp->f_ops->fo_poll)(fp, events, active_cred, td));

}

static __inline int

fo_stat(fp, sb, active_cred, td)

	struct file *fp;

	struct stat *sb;

	struct ucred *active_cred;

	struct thread *td;

{

	return ((*fp->f_ops->fo_stat)(fp, sb, active_cred, td));

}

static __inline int

fo_close(fp, td)

	struct file *fp;

	struct thread *td;

{

	return ((*fp->f_ops->fo_close)(fp, td));

}

static __inline int

fo_kqfilter(fp, kn)

	struct file *fp;

	struct knote *kn;

{

	return ((*fp->f_ops->fo_kqfilter)(fp, kn));

}

#endif /* _KERNEL */

#endif /* !SYS_FILE_H */