freebsd-skq/share/man/man9/VOP_INACTIVE.9
Matthew Dillon fe11eb74af Update errors in documentation for various VOP_ calls. Specifically,
describe the correct locking state expected on entry and return.
1999-09-24 07:07:02 +00:00

107 lines
2.9 KiB
Groff

.\" -*- nroff -*-
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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 filesystem resources for a vnode
.Sh SYNOPSIS
.Fd #include <sys/param.h>
.Fd #include <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
.Pp
The arguments are:
.Bl -tag -width vp
.It Ar 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
.Pp
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.
.Pp
.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 .