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.\" Copyright (C) 2008 Chad David <davidc@acns.ab.ca>.
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.\" $FreeBSD: release/9.1.0/share/man/man9/insmntque.9 209031 2010-06-11 06:03:47Z uqs $
.\"
.Dd September 8, 2008
.Dt INSMNTQUE 9
.Os
.Sh NAME
.Nm insmntque ,
.Nm insmntque1
.Nd "associate a vnode with a mount"
.Sh SYNOPSIS
.In sys/param.h
.In sys/vnode.h
.Ft int
.Fn insmntque "struct vnode *vp" "struct mount *mp"
.Ft int
.Fn insmntque1 "struct vnode *vp" "struct mount *mp" "void (*dtr)(struct vnode *, void *)" "void *dtr_arg"
.Sh DESCRIPTION
The
.Fn insmntque
function associates a vnode with a mount.
This includes updating
.Va v_mount
for the vnode, and inserting the vnode into the mount's vnode list.
.Pp
The mount reference count is incremented for each vnode added to the
mount, and that reference is decremented by
.Xr vgone 9 .
.Pp
The mount's interlock is held while the vnode is inserted.
For MP-safe file systems, the vnode must be exclusively locked.
.Pp
On failure,
.Fn insmntque
calls
.Xr vgone 9
on the supplied vnode, and then drops the vnode lock and reference.
If more elaborated cleanup after
.Fn insmntque
failure is needed, the
.Fn insmntque1
function may be used instead.
The
.Fa dtr
argument is a pointer to a function that is called on failure.
This function may perform any custom cleanup.
The vnode pointer is supplied as the first argument to
.Fa dtr .
The
.Fa dtr_arg
argument is the second, supplying any additional context needed.
.Sh RETURN VALUES
The
.Fn insmntque
function will always return 0, unless the file system is currently being unmounted
in which case it may return
.Dv EBUSY .
Also,
.Fn insmntque
may be forced to insert the vnode into the mount's vnode list
by setting the
.Va VV_FORCEINSMQ
flag in the vnode
.Va v_flag ,
even if the file system is being unmounted.
.Sh SEE ALSO
.Xr vgone 9
.Sh AUTHORS
This manual page was written by
.An Chad David Aq davidc@acns.ab.ca .