2 * Copyright (c) 1992, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software donated to Berkeley by
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9 * modification, are permitted provided that the following conditions
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12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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32 * @(#)null.h 8.3 (Berkeley) 8/20/94
40 #define NULLM_CACHE 0x0001
43 struct mount *nullm_vfs;
44 struct vnode *nullm_rootvp; /* Reference to root null_node */
50 * A cache of vnode references
53 LIST_ENTRY(null_node) null_hash; /* Hash list */
54 struct vnode *null_lowervp; /* VREFed once */
55 struct vnode *null_vnode; /* Back pointer */
59 #define NULLV_NOUNLOCK 0x0001
60 #define NULLV_DROP 0x0002
62 #define MOUNTTONULLMOUNT(mp) ((struct null_mount *)((mp)->mnt_data))
63 #define VTONULL(vp) ((struct null_node *)(vp)->v_data)
64 #define NULLTOV(xp) ((xp)->null_vnode)
66 int nullfs_init(struct vfsconf *vfsp);
67 int nullfs_uninit(struct vfsconf *vfsp);
68 int null_nodeget(struct mount *mp, struct vnode *target, struct vnode **vpp);
69 struct vnode *null_hashget(struct mount *mp, struct vnode *lowervp);
70 void null_hashrem(struct null_node *xp);
71 int null_bypass(struct vop_generic_args *ap);
74 struct vnode *null_checkvp(struct vnode *vp, char *fil, int lno);
75 #define NULLVPTOLOWERVP(vp) null_checkvp((vp), __FILE__, __LINE__)
77 #define NULLVPTOLOWERVP(vp) (VTONULL(vp)->null_lowervp)
80 extern struct vop_vector null_vnodeops;
83 MALLOC_DECLARE(M_NULLFSNODE);
87 #define NULLFSDEBUG(format, args...) printf(format ,## args)
89 #define NULLFSDEBUG(format, args...)
90 #endif /* NULLFS_DEBUG */