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34 * @(#)null.h 8.3 (Berkeley) 8/20/94
42 #define NULLM_CACHE 0x0001
45 struct mount *nullm_vfs;
46 struct vnode *nullm_lowerrootvp; /* Ref to lower root vnode */
52 * A cache of vnode references
55 LIST_ENTRY(null_node) null_hash; /* Hash list */
56 struct vnode *null_lowervp; /* VREFed once */
57 struct vnode *null_vnode; /* Back pointer */
61 #define NULLV_NOUNLOCK 0x0001
62 #define NULLV_DROP 0x0002
64 #define MOUNTTONULLMOUNT(mp) ((struct null_mount *)((mp)->mnt_data))
65 #define VTONULL(vp) ((struct null_node *)(vp)->v_data)
66 #define NULLTOV(xp) ((xp)->null_vnode)
68 int nullfs_init(struct vfsconf *vfsp);
69 int nullfs_uninit(struct vfsconf *vfsp);
70 int null_nodeget(struct mount *mp, struct vnode *target, struct vnode **vpp);
71 struct vnode *null_hashget(struct mount *mp, struct vnode *lowervp);
72 void null_hashrem(struct null_node *xp);
73 int null_bypass(struct vop_generic_args *ap);
76 struct vnode *null_checkvp(struct vnode *vp, char *fil, int lno);
77 #define NULLVPTOLOWERVP(vp) null_checkvp((vp), __FILE__, __LINE__)
79 #define NULLVPTOLOWERVP(vp) (VTONULL(vp)->null_lowervp)
82 extern struct vop_vector null_vnodeops;
85 MALLOC_DECLARE(M_NULLFSNODE);
89 #define NULLFSDEBUG(format, args...) printf(format ,## args)
91 #define NULLFSDEBUG(format, args...)
92 #endif /* NULLFS_DEBUG */