1/* $NetBSD: overlay.h,v 1.8 2008/06/28 01:34:06 rumble 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(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)(void *);
124extern struct vfsops overlay_vfsops;
125
126#endif /* _KERNEL */
127