FreeBSD-5.3/share/man/man9/VOP_INACTIVE.9

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.\" Copyright (c) 1996 Doug Rabson
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.Dd July 24, 1996
.Os
.Dt VOP_INACTIVE 9
.Sh NAME
.Nm VOP_INACTIVE ,
.Nm VOP_RECLAIM
.Nd reclaim file system resources for a vnode
.Sh SYNOPSIS
.In sys/param.h
.In sys/vnode.h
.Ft int
.Fn VOP_INACTIVE "struct vnode *vp" "struct thread *td"
.Ft int
.Fn VOP_RECLAIM "struct vnode *vp" "struct thread *td"
.Sh DESCRIPTION
The arguments are:
.Bl -tag -width 2n
.It Fa vp
the vnode being reclaimed
.El
.Pp
.Fn VOP_INACTIVE
is called when the kernel is no longer using the vnode.
This may be
because the reference count reaches zero or it may be that the
file system is being forcibly unmounted while there are open files.
It can be used to reclaim space for
.Sq open but deleted
files.
.Pp
.Fn VOP_RECLAIM
is called when a vnode is being reused for a different file system.
Any file system specific resources associated with the vnode should be
freed.
.Sh LOCKS
For VOP_INACTIVE, the
.Fa vp
will be locked on entry.
Your VOP_INACTIVE code
must unlock the
.Fa vp
prior to returning.
.Pp
For VOP_RECLAIM, the
.Fa vp
will not be locked on entry and should be left unlocked on return.
.Sh PSEUDOCODE
.Bd -literal
int
vop_inactive(struct vnode *vp, struct thread *td)
{
    if (link count of vp == 0) {
	/*
	 * Reclaim space in file system for vp.
	 */
	...;
    }
    VOP_UNLOCK(vp, 0, td);

    return 0;
}

int
vop_reclaim(struct vnode *vp, struct thread *td)
{
    /*
     * Clean out the name cache.
     */
    cache_purge(vp);

    /*
     * Free file system related data.
     */
    ...;

    return 0;
}
.Ed
.Sh SEE ALSO
.Xr vnode 9
.Sh AUTHORS
This man page was written by
.An Doug Rabson .