1/* $NetBSD: layer.h,v 1.16 2014/05/28 10:51:20 hannken 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#ifndef _MISCFS_GENFS_LAYER_H_
72#define _MISCFS_GENFS_LAYER_H_
73
74struct layer_args {
75 char *target; /* Target of loopback */
76 struct export_args30 _pad1; /* compat with old userland tools */
77};
78
79#ifdef _KERNEL
80
81struct layer_mount {
82 struct mount *layerm_vfs;
83 struct vnode *layerm_rootvp; /* Ref to root layer_node */
84 u_int layerm_flags; /* mount point layer flags */
85 u_int layerm_size; /* size of fs's struct node */
86 enum vtagtype layerm_tag; /* vtag of our vnodes */
87 int /* bypass routine for this mount */
88 (*layerm_bypass)(void *);
89 int (**layerm_vnodeop_p) /* ops for our nodes */
90 (void *);
91};
92
93#define LAYERFS_MFLAGS 0x00000fff /* reserved layer mount flags */
94#define LAYERFS_MBYPASSDEBUG 0x00000001
95
96/*
97 * A cache of vnode references
98 */
99struct layer_node {
100 struct vnode *layer_lowervp; /* VREFed once */
101 struct vnode *layer_vnode; /* Back pointer */
102 unsigned int layer_flags; /* locking, etc. */
103};
104
105#define LAYERFS_RESFLAGS 0x00000fff /* flags reserved for layerfs */
106#define LAYERFS_REMOVED 0x00000001 /* Did a remove on this node */
107
108#define LAYERFS_DO_BYPASS(vp, ap) \
109 (*MOUNTTOLAYERMOUNT((vp)->v_mount)->layerm_bypass)((ap))
110
111struct vnode *layer_checkvp(struct vnode *vp, const char *fil, int lno);
112
113#define MOUNTTOLAYERMOUNT(mp) ((struct layer_mount *)((mp)->mnt_data))
114#define VTOLAYER(vp) ((struct layer_node *)(vp)->v_data)
115#define LAYERTOV(xp) ((xp)->layer_vnode)
116#ifdef LAYERFS_DIAGNOSTIC
117#define LAYERVPTOLOWERVP(vp) layer_checkvp((vp), __FILE__, __LINE__)
118extern int layerfs_debug;
119#else
120#define LAYERVPTOLOWERVP(vp) (VTOLAYER(vp)->layer_lowervp)
121#endif
122
123#endif /* _KERNEL */
124#endif /* _MISCFS_GENFS_LAYER_H_ */
125