xref: /dragonfly/share/man/man9/VOP_INACTIVE.9 (revision c9f721c2) 
1.\" Copyright (c) 1996 Doug Rabson
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27.\" $FreeBSD: src/share/man/man9/VOP_INACTIVE.9,v 1.5.2.3 2001/12/17 11:30:18 ru Exp $
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30.Dd July 24, 1996
31.Os
32.Dt VOP_INACTIVE 9
33.Sh NAME
34.Nm VOP_INACTIVE ,
35.Nm VOP_RECLAIM
36.Nd reclaim filesystem resources for a vnode
37.Sh SYNOPSIS
38.In sys/param.h
39.In sys/vnode.h
40.Ft int
41.Fn VOP_INACTIVE "struct vnode *vp" "struct proc *p"
42.Ft int
43.Fn VOP_RECLAIM "struct vnode *vp" "struct proc *p"
44.Sh DESCRIPTION
45The arguments are:
46.Bl -tag -width 2n
47.It Fa vp
48the vnode being reclaimed
49.El
50.Pp
51.Xr VOP_INACTIVE 9
52is called when the kernel is no longer using the vnode.  This may be
53because the reference count reaches zero or it may be that the
54filesystem is being forcibly unmounted while there are open files.
55It can be used to reclaim space for 'open but deleted' files.
56.Xr VOP_RECLAIM 9
57is called when a vnode is being reused for a different filesystem.
58Any filesystem specific resources associated with the vnode should be
59freed.
60.Sh LOCKS
61For VOP_INACTIVE, the vp will be locked on entry.  Your VOP_INACTIVE code
62must unlock the vp prior to returning.
63.Pp
64For VOP_RECLAIM, the vp will not be locked on entry and should be left
65unlocked on return.
66.Sh PSEUDOCODE
67.Bd -literal
68int
69vop_inactive(struct vnode *vp)
70{
71    if (link count of vp == 0) {
72	/*
73	 * Reclaim space in filesystem for vp.
74	 */
75	...;
76    }
77    VOP_UNLOCK(vp, 0, p);
78
79    return 0;
80}
81
82int
83vop_reclaim(struct vnode *vp)
84{
85    /*
86     * Clean out the name cache.
87     */
88    cache_purge(vp);
89
90    /*
91     * Free filesystem-related data.
92     */
93    ...;
94
95    return 0;
96}
97.Ed
98.Sh SEE ALSO
99.Xr vnode 9
100.Sh AUTHORS
101This man page was written by
102.An Doug Rabson .
103