xref: /dragonfly/share/man/man9/VOP_INACTIVE.9 (revision 2d8a3be7) 
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3.\" Copyright (c) 1996 Doug Rabson
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32.Dd July 24, 1996
33.Os
34.Dt VOP_INACTIVE 9
35.Sh NAME
36.Nm VOP_INACTIVE ,
37.Nm VOP_RECLAIM
38.Nd reclaim filesystem resources for a vnode
39.Sh SYNOPSIS
40.In sys/param.h
41.In sys/vnode.h
42.Ft int
43.Fn VOP_INACTIVE "struct vnode *vp" "struct proc *p"
44.Ft int
45.Fn VOP_RECLAIM "struct vnode *vp" "struct proc *p"
46.Sh DESCRIPTION
47The arguments are:
48.Bl -tag -width 2n
49.It Fa vp
50the vnode being reclaimed
51.El
52.Pp
53.Xr VOP_INACTIVE 9
54is called when the kernel is no longer using the vnode.  This may be
55because the reference count reaches zero or it may be that the
56filesystem is being forcibly unmounted while there are open files.
57It can be used to reclaim space for 'open but deleted' files.
58.Xr VOP_RECLAIM 9
59is called when a vnode is being reused for a different filesystem.
60Any filesystem specific resources associated with the vnode should be
61freed.
62.Sh LOCKS
63For VOP_INACTIVE, the vp will be locked on entry.  Your VOP_INACTIVE code
64must unlock the vp prior to returning.
65.Pp
66For VOP_RECLAIM, the vp will not be locked on entry and should be left
67unlocked on return.
68.Sh PSEUDOCODE
69.Bd -literal
70int
71vop_inactive(struct vnode *vp)
72{
73    if (link count of vp == 0) {
74	/*
75	 * Reclaim space in filesystem for vp.
76	 */
77	...;
78    }
79    VOP_UNLOCK(vp, 0, p);
80
81    return 0;
82}
83
84int
85vop_reclaim(struct vnode *vp)
86{
87    /*
88     * Clean out the name cache.
89     */
90    cache_purge(vp);
91
92    /*
93     * Free filesystem-related data.
94     */
95    ...;
96
97    return 0;
98}
99.Ed
100.Sh SEE ALSO
101.Xr vnode 9
102.Sh AUTHORS
103This man page was written by
104.An Doug Rabson .
105