/* * Copyright (c) 1992, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software donated to Berkeley by * Jan-Simon Pendry. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)null.h 8.2 (Berkeley) 1/21/94 * * $Id: null.h,v 1.1.1.1 1994/05/24 10:05:04 rgrimes Exp $ */ struct null_args { char *target; /* Target of loopback */ }; struct null_mount { struct mount *nullm_vfs; struct vnode *nullm_rootvp; /* Reference to root null_node */ }; #ifdef KERNEL /* * A cache of vnode references */ struct null_node { struct null_node *null_forw; /* Hash chain */ struct null_node *null_back; struct vnode *null_lowervp; /* VREFed once */ struct vnode *null_vnode; /* Back pointer */ }; extern int null_node_create __P((struct mount *mp, struct vnode *target, struct vnode **vpp)); #define MOUNTTONULLMOUNT(mp) ((struct null_mount *)((mp)->mnt_data)) #define VTONULL(vp) ((struct null_node *)(vp)->v_data) #define NULLTOV(xp) ((xp)->null_vnode) #ifdef NULLFS_DIAGNOSTIC extern struct vnode *null_checkvp __P((struct vnode *vp, char *fil, int lno)); #define NULLVPTOLOWERVP(vp) null_checkvp((vp), __FILE__, __LINE__) #else #define NULLVPTOLOWERVP(vp) (VTONULL(vp)->null_lowervp) #endif extern vop_t **null_vnodeop_p; extern struct vfsops null_vfsops; #endif /* KERNEL */