File:  [DragonFly] / src / share / man / man9 / VOP_INACTIVE.9
Revision 1.3: download - view: text, annotated - select for diffs
Sun Jul 27 05:36:06 2003 UTC (10 years, 11 months ago) by hmp
Branches: MAIN
CVS tags: HEAD
mdoc(7) assorted fixes:

	- Nuke usage of .Ar from Section 9.  The `.Ar' macro
	  should only be used for userland manual pages.

	- Replace usage of `.Ar' with `.Va' or `.Vt' as necessary.

.\" -*- nroff -*-
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.\" Copyright (c) 1996 Doug Rabson
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.\" $FreeBSD: src/share/man/man9/VOP_INACTIVE.9,v 1.5.2.3 2001/12/17 11:30:18 ru Exp $
.\" $DragonFly: src/share/man/man9/VOP_INACTIVE.9,v 1.3 2003/07/27 05:36:06 hmp Exp $
.\"
.Dd July 24, 1996
.Os
.Dt VOP_INACTIVE 9
.Sh NAME
.Nm VOP_INACTIVE ,
.Nm VOP_RECLAIM
.Nd reclaim filesystem resources for a vnode
.Sh SYNOPSIS
.In sys/param.h
.In sys/vnode.h
.Ft int
.Fn VOP_INACTIVE "struct vnode *vp" "struct proc *p"
.Ft int
.Fn VOP_RECLAIM "struct vnode *vp" "struct proc *p"
.Sh DESCRIPTION
The arguments are:
.Bl -tag -width 2n
.It Fa vp
the vnode being reclaimed
.El
.Pp
.Xr VOP_INACTIVE 9
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
filesystem is being forcibly unmounted while there are open files.
It can be used to reclaim space for 'open but deleted' files.
.Xr VOP_RECLAIM 9
is called when a vnode is being reused for a different filesystem.
Any filesystem specific resources associated with the vnode should be
freed.
.Sh LOCKS
For VOP_INACTIVE, the vp will be locked on entry.  Your VOP_INACTIVE code
must unlock the vp prior to returning.
.Pp
For VOP_RECLAIM, the vp will not be locked on entry and should be left
unlocked on return.
.Sh PSEUDOCODE
.Bd -literal
int
vop_inactive(struct vnode *vp)
{
    if (link count of vp == 0) {
	/*
	 * Reclaim space in filesystem for vp.
	 */
	...;
    }
    VOP_UNLOCK(vp, 0, p);

    return 0;
}

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

    /*
     * Free filesystem-related data.
     */
    ...;

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