vnode.h

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#define VNODEOP_SET(f) DATA_SET(MODVNOPS,f)
#else
#define VNODEOP_SET(f) DATA_SET(vfs_opv_descs_,f)
#endif

/*
 * Global vnode data.
 */
extern	struct vnode *rootvnode;	/* root (i.e. "/") vnode */
extern	int desiredvnodes;		/* number of vnodes desired */
extern	int prtactive;			/* nonzero to call vprint() */
extern	struct vattr va_null;		/* predefined null vattr structure */

/*
 * Macro/function to check for client cache inconsistency w.r.t. leasing.
 */
#define	LEASE_READ	0x1		/* Check lease for readers */
#define	LEASE_WRITE	0x2		/* Check lease for modifiers */

extern void	(*lease_check) __P((struct vnode *vp, struct proc *p,
				    struct ucred *ucred, int flag));
extern void	(*lease_updatetime) __P((int deltat));

#ifdef NFS
#ifdef NQNFS
#define	LEASE_CHECK(vp, p, cred, flag)	lease_check((vp), (p), (cred), (flag))
#define	LEASE_UPDATETIME(dt)		lease_updatetime(dt)
#else
#define LEASE_CHECK(vp, p, cred, flag)
#define LEASE_UPDATETIME(dt)
#endif /* NQNFS */
#else
#define LEASE_CHECK(vp, p, cred, flag) \
	do { if(lease_check) lease_check((vp), (p), (cred), (flag)); } while(0)
#define LEASE_UPDATETIME(dt) \
	do { if(lease_updatetime) lease_updatetime(dt); } while(0)
#endif /* NFS */
#endif /* KERNEL */


/*
 * Mods for exensibility.
 */

/*
 * Flags for vdesc_flags:
 */
#define VDESC_MAX_VPS		16
/* Low order 16 flag bits are reserved for willrele flags for vp arguments. */
#define VDESC_VP0_WILLRELE	0x0001
#define VDESC_VP1_WILLRELE	0x0002
#define VDESC_VP2_WILLRELE	0x0004
#define VDESC_VP3_WILLRELE	0x0008
#define VDESC_NOMAP_VPP		0x0100
#define VDESC_VPP_WILLRELE	0x0200

/*
 * VDESC_NO_OFFSET is used to identify the end of the offset list
 * and in places where no such field exists.
 */
#define VDESC_NO_OFFSET -1

/*
 * This structure describes the vnode operation taking place.
 */
struct vnodeop_desc {
	int	vdesc_offset;		/* offset in vector--first for speed */
	char    *vdesc_name;		/* a readable name for debugging */
	int	vdesc_flags;		/* VDESC_* flags */

	/*
	 * These ops are used by bypass routines to map and locate arguments.
	 * Creds and procs are not needed in bypass routines, but sometimes
	 * they are useful to (for example) transport layers.
	 * Nameidata is useful because it has a cred in it.
	 */
	int	*vdesc_vp_offsets;	/* list ended by VDESC_NO_OFFSET */
	int	vdesc_vpp_offset;	/* return vpp location */
	int	vdesc_cred_offset;	/* cred location, if any */
	int	vdesc_proc_offset;	/* proc location, if any */
	int	vdesc_componentname_offset; /* if any */
	/*
	 * Finally, we've got a list of private data (about each operation)
	 * for each transport layer.  (Support to manage this list is not
	 * yet part of BSD.)
	 */
	caddr_t	*vdesc_transports;
};

#ifdef KERNEL
/*
 * A list of all the operation descs.
 */
extern struct vnodeop_desc *vnodeop_descs[];


/*
 * This macro is very helpful in defining those offsets in the vdesc struct.
 *
 * This is stolen from X11R4.  I ingored all the fancy stuff for
 * Crays, so if you decide to port this to such a serious machine,
 * you might want to consult Intrisics.h's XtOffset{,Of,To}.
 */
#define VOPARG_OFFSET(p_type,field) \
        ((int) (((char *) (&(((p_type)NULL)->field))) - ((char *) NULL)))
#define VOPARG_OFFSETOF(s_type,field) \
	VOPARG_OFFSET(s_type*,field)
#define VOPARG_OFFSETTO(S_TYPE,S_OFFSET,STRUCT_P) \
	((S_TYPE)(((char*)(STRUCT_P))+(S_OFFSET)))


/*
 * This structure is used to configure the new vnodeops vector.
 */
struct vnodeopv_entry_desc {
	struct vnodeop_desc *opve_op;   /* which operation this is */
	int (*opve_impl)();		/* code implementing this operation */
};
struct vnodeopv_desc {
			/* ptr to the ptr to the vector where op should go */
	int (***opv_desc_vector_p)();
	struct vnodeopv_entry_desc *opv_desc_ops;   /* null terminated list */
};

/*
 * A default routine which just returns an error.
 */
int vn_default_error __P((void));

/*
 * A generic structure.
 * This can be used by bypass routines to identify generic arguments.
 */
struct vop_generic_args {
	struct vnodeop_desc *a_desc;
	/* other random data follows, presumably */
};

/*
 * VOCALL calls an op given an ops vector.  We break it out because BSD's
 * vclean changes the ops vector and then wants to call ops with the old
 * vector.
 */
#define VOCALL(OPSV,OFF,AP) (( *((OPSV)[(OFF)])) (AP))

/*
 * This call works for vnodes in the kernel.
 */
#define VCALL(VP,OFF,AP) VOCALL((VP)->v_op,(OFF),(AP))
#define VDESC(OP) (& __CONCAT(OP,_desc))
#define VOFFSET(OP) (VDESC(OP)->vdesc_offset)

/*
 * Finally, include the default set of vnode operations.
 */
#include <vnode_if.h>

/*
 * Public vnode manipulation functions.
 */
struct componentname;
struct file;
struct mount;
struct nameidata;
struct proc;
struct stat;
struct ucred;
struct uio;
struct vattr;
struct vnode;
struct vop_bwrite_args;

int 	bdevvp __P((dev_t dev, struct vnode **vpp));
/* cache_* may belong in namei.h. */
void	cache_enter __P((struct vnode *dvp, struct vnode *vp,
	    struct componentname *cnp));
int	cache_lookup __P((struct vnode *dvp, struct vnode **vpp,
	    struct componentname *cnp));
void	cache_purge __P((struct vnode *vp));
void	cache_purgevfs __P((struct mount *mp));
int 	getnewvnode __P((enum vtagtype tag,
	    struct mount *mp, int (**vops)(), struct vnode **vpp));
int	vinvalbuf __P((struct vnode *vp, int save, struct ucred *cred,
	    struct proc *p, int slpflag, int slptimeo));
void 	vattr_null __P((struct vattr *vap));
int 	vcount __P((struct vnode *vp));
int	vfinddev __P((dev_t dev, enum vtype type, struct vnode **vpp));
int 	vget __P((struct vnode *vp, int lockflag));
void 	vgone __P((struct vnode *vp));
void 	vgoneall __P((struct vnode *vp));
int	vn_bwrite __P((struct vop_bwrite_args *ap));
int 	vn_close __P((struct vnode *vp,
	    int flags, struct ucred *cred, struct proc *p));
int 	vn_closefile __P((struct file *fp, struct proc *p));
int	vn_ioctl __P((struct file *fp, int com, caddr_t data, struct proc *p));
int 	vn_open __P((struct nameidata *ndp, int fmode, int cmode));
int 	vn_rdwr __P((enum uio_rw rw, struct vnode *vp, caddr_t base,
	    int len, off_t offset, enum uio_seg segflg, int ioflg,
	    struct ucred *cred, int *aresid, struct proc *p));
int	vn_read __P((struct file *fp, struct uio *uio, struct ucred *cred));
int	vn_select __P((struct file *fp, int which, struct proc *p));
int	vn_stat __P((struct vnode *vp, struct stat *sb, struct proc *p));
int	vn_write __P((struct file *fp, struct uio *uio, struct ucred *cred));
struct vnode *
	checkalias __P((struct vnode *vp, dev_t nvp_rdev, struct mount *mp));
void	vprint __P((char *, struct vnode *));
void 	vput __P((struct vnode *vp));
void 	vref __P((struct vnode *vp));
void 	vrele __P((struct vnode *vp));
int 	vn_writechk __P((struct vnode *vp));

void	vfs_opv_init __P((struct vnodeopv_desc **));
#endif /* KERNEL */

#endif /* !_SYS_VNODE_H_ */