overlay.h revision 1.4
1/* $NetBSD: overlay.h,v 1.4 2003/08/07 16:32:39 agc Exp $ */ 2 3/* 4 * Copyright (c) 1999 National Aeronautics & Space Administration 5 * All rights reserved. 6 * 7 * This software was written by William Studenmund of the 8 * Numerical Aerospace Simulation Facility, NASA Ames Research Center. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the National Aeronautics & Space Administration 19 * nor the names of its contributors may be used to endorse or promote 20 * products derived from this software without specific prior written 21 * permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE NATIONAL AERONAUTICS & SPACE ADMINISTRATION 24 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 25 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 26 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE ADMINISTRATION OR CONTRIB- 27 * UTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 28 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 29 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 30 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 31 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 32 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 33 * POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36/* 37 * Copyright (c) 1992, 1993 38 * The Regents of the University of California. All rights reserved. 39 * 40 * This code is derived from software donated to Berkeley by 41 * Jan-Simon Pendry. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. Neither the name of the University nor the names of its contributors 52 * may be used to endorse or promote products derived from this software 53 * without specific prior written permission. 54 * 55 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 56 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 57 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 58 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 59 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 60 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 61 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 62 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 63 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 64 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 65 * SUCH DAMAGE. 66 * 67 * from: Id: lofs.h,v 1.8 1992/05/30 10:05:43 jsp Exp 68 * @(#)null.h 8.2 (Berkeley) 1/21/94 69 */ 70 71#include <miscfs/genfs/layer.h> 72 73struct overlay_args { 74 struct layer_args la; /* generic layerfs args */ 75}; 76/* 77 * We leave ova_target for two reasons. One, we can tell the difference 78 * between a mount_overlay -u and a call from mountd as the former will 79 * pass a pointer to a string while the latter will pass NULL. Two, 80 * filesystems based on the overlay layer might have use for it. 81 */ 82#define ova_target la.target 83#define ova_export la.export 84 85#ifdef _KERNEL 86struct overlay_mount { 87 struct layer_mount lm; /* generic layerfs mount stuff */ 88}; 89#define ovm_vfs lm.layerm_vfs 90#define ovm_rootvp lm.layerm_rootvp 91#define ovm_export lm.layerm_export 92#define ovm_flags lm.layerm_flags 93#define ovm_size lm.layerm_size 94#define ovm_tag lm.layerm_tag 95#define ovm_bypass lm.layerm_bypass 96#define ovm_alloc lm.layerm_alloc 97#define ovm_vnodeop_p lm.layerm_vnodeop_p 98#define ovm_node_hashtbl lm.layerm_node_hashtbl 99#define ovm_node_hash lm.layerm_node_hash 100#define ovm_hashlock lm.layerm_hashlock 101 102/* 103 * A cache of vnode references 104 */ 105struct overlay_node { 106 struct layer_node ln; 107}; 108#define ov_hash ln.layer_hash 109#define ov_lowervp ln.layer_lowervp 110#define ov_vnode ln.layer_vnode 111#define ov_flags ln.layer_flags 112 113#define MOUNTTOOVERLAYMOUNT(mp) ((struct overlay_mount *)((mp)->mnt_data)) 114#define VTOOVERLAY(vp) ((struct overlay_node *)(vp)->v_data) 115#define OVERLAYTOV(xp) ((xp)->ov_vnode) 116#ifdef OVERLAYFS_DIAGNOSTIC 117extern struct vnode *layer_checkvp __P((struct vnode *vp, char *fil, int lno)); 118#define OVERLAYVPTOLOWERVP(vp) layer_checkvp((vp), __FILE__, __LINE__) 119#else 120#define OVERLAYVPTOLOWERVP(vp) (VTOOVERLAY(vp)->ov_lowervp) 121#endif 122 123extern int (**overlay_vnodeop_p) __P((void *)); 124extern struct vfsops overlay_vfsops; 125 126#endif /* _KERNEL */ 127