xref: /dflybsd-src/share/man/man9/vcount.9 (revision 86d7f5d305c6adaa56ff4582ece9859d73106103)
186d7f5d3SJohn Marino.\"
286d7f5d3SJohn Marino.\" Copyright (c) 2009
386d7f5d3SJohn Marino.\"	The DragonFly Project.  All rights reserved.
486d7f5d3SJohn Marino.\"
586d7f5d3SJohn Marino.\" Redistribution and use in source and binary forms, with or without
686d7f5d3SJohn Marino.\" modification, are permitted provided that the following conditions
786d7f5d3SJohn Marino.\" are met:
886d7f5d3SJohn Marino.\"
986d7f5d3SJohn Marino.\" 1. Redistributions of source code must retain the above copyright
1086d7f5d3SJohn Marino.\"    notice, this list of conditions and the following disclaimer.
1186d7f5d3SJohn Marino.\" 2. Redistributions in binary form must reproduce the above copyright
1286d7f5d3SJohn Marino.\"    notice, this list of conditions and the following disclaimer in
1386d7f5d3SJohn Marino.\"    the documentation and/or other materials provided with the
1486d7f5d3SJohn Marino.\"    distribution.
1586d7f5d3SJohn Marino.\" 3. Neither the name of The DragonFly Project nor the names of its
1686d7f5d3SJohn Marino.\"    contributors may be used to endorse or promote products derived
1786d7f5d3SJohn Marino.\"    from this software without specific, prior written permission.
1886d7f5d3SJohn Marino.\"
1986d7f5d3SJohn Marino.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
2086d7f5d3SJohn Marino.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
2186d7f5d3SJohn Marino.\" LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
2286d7f5d3SJohn Marino.\" FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
2386d7f5d3SJohn Marino.\" COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
2486d7f5d3SJohn Marino.\" INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
2586d7f5d3SJohn Marino.\" BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
2686d7f5d3SJohn Marino.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
2786d7f5d3SJohn Marino.\" AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
2886d7f5d3SJohn Marino.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
2986d7f5d3SJohn Marino.\" OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
3086d7f5d3SJohn Marino.\" SUCH DAMAGE.
3186d7f5d3SJohn Marino.\"
3286d7f5d3SJohn Marino.Dd December 14, 2009
3386d7f5d3SJohn Marino.Dt VCOUNT 9
3486d7f5d3SJohn Marino.Os
3586d7f5d3SJohn Marino.Sh NAME
3686d7f5d3SJohn Marino.Nm vcount ,
3786d7f5d3SJohn Marino.Nm count_dev
3886d7f5d3SJohn Marino.Nd "get total number of references to a device"
3986d7f5d3SJohn Marino.Sh SYNOPSIS
4086d7f5d3SJohn Marino.In sys/conf.h
4186d7f5d3SJohn Marino.In sys/vnode.h
4286d7f5d3SJohn Marino.Ft int
4386d7f5d3SJohn Marino.Fn vcount "struct vnode *vp"
4486d7f5d3SJohn Marino.Ft int
4586d7f5d3SJohn Marino.Fn count_dev "cdev_t dev"
4686d7f5d3SJohn Marino.Sh DESCRIPTION
4786d7f5d3SJohn Marino.Fn vcount
4886d7f5d3SJohn Marinois used to get the number of references to a special device.
4986d7f5d3SJohn MarinoThis makes sense because multiple vnodes may reference the same device.
5086d7f5d3SJohn Marino.Pp
5186d7f5d3SJohn Marino.Fn count_dev
5286d7f5d3SJohn Marinodoes the same thing as
5386d7f5d3SJohn Marino.Fn vcount ,
5486d7f5d3SJohn Marinobut takes a
5586d7f5d3SJohn Marino.Vt cdev_t
5686d7f5d3SJohn Marinorather than a
5786d7f5d3SJohn Marino.Vt "struct vnode"
5886d7f5d3SJohn Marinopointer as an argument.
5986d7f5d3SJohn MarinoIt may only be called for
6086d7f5d3SJohn Marino.Dv VBLK
6186d7f5d3SJohn Marinoand
6286d7f5d3SJohn Marino.Dv VCHR
6386d7f5d3SJohn Marinovnodes since
6486d7f5d3SJohn Marino.Fa v_rdev
6586d7f5d3SJohn Marinois an overloaded field.
6686d7f5d3SJohn Marino.Sh RETURN VALUES
6786d7f5d3SJohn Marino.Fn vcount
6886d7f5d3SJohn Marinoand
6986d7f5d3SJohn Marino.Fn count_dev
7086d7f5d3SJohn Marinoboth return the number of references to the device.
7186d7f5d3SJohn Marino.Sh SEE ALSO
7286d7f5d3SJohn Marino.Xr vnode 9
73