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36 * @(#)null.h 8.3 (Berkeley) 8/20/94
38 * $FreeBSD: src/sys/miscfs/nullfs/null.h,v 1.11.2.3 2001/06/26 04:20:09 bp Exp $
39 * $DragonFly: src/sys/vfs/nullfs/null.h,v 1.5 2004/08/17 18:57:34 dillon Exp $
43 char *target; /* Target of loopback */
47 struct mount *nullm_vfs;
48 struct vnode *nullm_rootvp; /* Reference to root null_node */
53 * A cache of vnode references
56 struct lock null_lock; /* Lock for this vnode. MBF */
57 struct lock *null_vnlock; /* lock of lower vnode in the stack */
58 LIST_ENTRY(null_node) null_hash; /* Hash list */
59 struct vnode *null_lowervp; /* vrefed once */
60 struct vnode *null_vnode; /* Back pointer */
63 #define MOUNTTONULLMOUNT(mp) ((struct null_mount *)((mp)->mnt_data))
64 #define VTONULL(vp) ((struct null_node *)(vp)->v_data)
65 #define NULLTOV(xp) ((xp)->null_vnode)
67 int nullfs_init(struct vfsconf *vfsp);
68 int nullfs_uninit(struct vfsconf *vfsp);
69 int null_node_create(struct mount *mp, struct vnode *target, struct vnode **vpp);
70 int null_bypass(struct vop_generic_args *ap);
73 struct vnode *null_checkvp(struct vnode *vp, char *fil, int lno);
74 #define NULLVPTOLOWERVP(vp) null_checkvp((vp), __FILE__, __LINE__)
76 #define NULLVPTOLOWERVP(vp) (VTONULL(vp)->null_lowervp)
79 extern struct lock null_hashlock;
82 MALLOC_DECLARE(M_NULLFSNODE);
86 #define NULLFSDEBUG(format, args...) printf(format ,## args)
88 #define NULLFSDEBUG(format, args...)
89 #endif /* NULLFS_DEBUG */