xref: /dragonfly/share/man/man9/VOP_INACTIVE.9 (revision cf89a63b) 
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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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29.Dd July 24, 1996
30.Dt VOP_INACTIVE 9
31.Os
32.Sh NAME
33.Nm VOP_INACTIVE ,
34.Nm VOP_RECLAIM
35.Nd reclaim filesystem resources for a vnode
36.Sh SYNOPSIS
37.In sys/param.h
38.In sys/vnode.h
39.Ft int
40.Fn VOP_INACTIVE "struct vnode *vp" "struct proc *p"
41.Ft int
42.Fn VOP_RECLAIM "struct vnode *vp" "struct proc *p"
43.Sh DESCRIPTION
44The arguments are:
45.Bl -tag -width 2n
46.It Fa vp
47the vnode being reclaimed
48.El
49.Pp
50.Xr VOP_INACTIVE 9
51is called when the kernel is no longer using the vnode.  This may be
52because the reference count reaches zero or it may be that the
53filesystem is being forcibly unmounted while there are open files.
54It can be used to reclaim space for 'open but deleted' files.
55.Xr VOP_RECLAIM 9
56is called when a vnode is being reused for a different filesystem.
57Any filesystem specific resources associated with the vnode should be
58freed.
59.Sh LOCKS
60For VOP_INACTIVE, the vp will be locked on entry.  Your VOP_INACTIVE code
61must unlock the vp prior to returning.
62.Pp
63For VOP_RECLAIM, the vp will not be locked on entry and should be left
64unlocked on return.
65.Sh PSEUDOCODE
66.Bd -literal
67int
68vop_inactive(struct vnode *vp)
69{
70    if (link count of vp == 0) {
71	/*
72	 * Reclaim space in filesystem for vp.
73	 */
74	...;
75    }
76    VOP_UNLOCK(vp, 0, p);
77
78    return 0;
79}
80
81int
82vop_reclaim(struct vnode *vp)
83{
84    /*
85     * Clean out the name cache.
86     */
87    cache_purge(vp);
88
89    /*
90     * Free filesystem-related data.
91     */
92    ...;
93
94    return 0;
95}
96.Ed
97.Sh SEE ALSO
98.Xr vnode 9
99.Sh AUTHORS
100This man page was written by
101.An Doug Rabson .
102