xref: /freebsd/share/man/man9/VOP_INACTIVE.9 (revision c17d43407fe04133a94055b0dbc7ea8965654a9f)
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29.\" $FreeBSD$
30.\"
31.Dd July 24, 1996
32.Os
33.Dt VOP_INACTIVE 9
34.Sh NAME
35.Nm VOP_INACTIVE ,
36.Nm VOP_RECLAIM
37.Nd reclaim filesystem resources for a vnode
38.Sh SYNOPSIS
39.In sys/param.h
40.In sys/vnode.h
41.Ft int
42.Fn VOP_INACTIVE "struct vnode *vp" "struct thread *td"
43.Ft int
44.Fn VOP_RECLAIM "struct vnode *vp" "struct thread *td"
45.Sh DESCRIPTION
46The arguments are:
47.Bl -tag -width 2n
48.It Ar vp
49the vnode being reclaimed
50.El
51.Pp
52.Xr VOP_INACTIVE 9
53is called when the kernel is no longer using the vnode.  This may be
54because the reference count reaches zero or it may be that the
55filesystem is being forcibly unmounted while there are open files.
56It can be used to reclaim space for 'open but deleted' files.
57.Xr VOP_RECLAIM 9
58is called when a vnode is being reused for a different filesystem.
59Any filesystem specific resources associated with the vnode should be
60freed.
61.Sh LOCKS
62For VOP_INACTIVE, the vp will be locked on entry.  Your VOP_INACTIVE code
63must unlock the vp prior to returning.
64.Pp
65For VOP_RECLAIM, the vp will not be locked on entry and should be left
66unlocked on return.
67.Sh PSEUDOCODE
68.Bd -literal
69int
70vop_inactive(struct vnode *vp, struct thread *td)
71{
72    if (link count of vp == 0) {
73	/*
74	 * Reclaim space in filesystem for vp.
75	 */
76	...;
77    }
78    VOP_UNLOCK(vp, 0, td);
79
80    return 0;
81}
82
83int
84vop_reclaim(struct vnode *vp, struct thread *td)
85{
86    /*
87     * Clean out the name cache.
88     */
89    cache_purge(vp);
90
91    /*
92     * Free filesystem-related data.
93     */
94    ...;
95
96    return 0;
97}
98.Ed
99.Sh SEE ALSO
100.Xr vnode 9
101.Sh AUTHORS
102This man page was written by
103.An Doug Rabson .
104