186d7f5d3SJohn Marino.\" $NetBSD: vnd.4,v 1.1 1995/12/30 18:10:48 thorpej Exp $ 286d7f5d3SJohn Marino.\" 386d7f5d3SJohn Marino.\" Copyright (c) 1995 Jason R. Thorpe. 486d7f5d3SJohn Marino.\" All rights reserved. 586d7f5d3SJohn Marino.\" 686d7f5d3SJohn Marino.\" Redistribution and use in source and binary forms, with or without 786d7f5d3SJohn Marino.\" modification, are permitted provided that the following conditions 886d7f5d3SJohn Marino.\" are met: 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 the 1386d7f5d3SJohn Marino.\" documentation and/or other materials provided with the distribution. 1486d7f5d3SJohn Marino.\" 3. All advertising materials mentioning features or use of this software 1586d7f5d3SJohn Marino.\" must display the following acknowledgement: 1686d7f5d3SJohn Marino.\" This product includes software developed for the NetBSD Project 1786d7f5d3SJohn Marino.\" by Jason R. Thorpe. 1886d7f5d3SJohn Marino.\" 4. Neither the name of the author nor the names of its contributors 1986d7f5d3SJohn Marino.\" may be used to endorse or promote products derived from this software 2086d7f5d3SJohn Marino.\" without specific prior written permission. 2186d7f5d3SJohn Marino.\" 2286d7f5d3SJohn Marino.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 2386d7f5d3SJohn Marino.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 2486d7f5d3SJohn Marino.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 2586d7f5d3SJohn Marino.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 2686d7f5d3SJohn Marino.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 2786d7f5d3SJohn Marino.\" BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 2886d7f5d3SJohn Marino.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 2986d7f5d3SJohn Marino.\" AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 3086d7f5d3SJohn Marino.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 3186d7f5d3SJohn Marino.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3286d7f5d3SJohn Marino.\" SUCH DAMAGE. 3386d7f5d3SJohn Marino.\" 3486d7f5d3SJohn Marino.\" $FreeBSD: src/share/man/man4/vn.4,v 1.6.2.4 2002/04/15 05:48:55 asmodai Exp $ 3586d7f5d3SJohn Marino.\" $DragonFly: src/share/man/man4/vn.4,v 1.6 2007/06/14 21:16:13 swildner Exp $ 3686d7f5d3SJohn Marino.\" 3786d7f5d3SJohn Marino.Dd September 28, 2009 3886d7f5d3SJohn Marino.Dt VN 4 3986d7f5d3SJohn Marino.Os 4086d7f5d3SJohn Marino.Sh NAME 4186d7f5d3SJohn Marino.Nm vn 4286d7f5d3SJohn Marino.Nd vnode disk driver 4386d7f5d3SJohn Marino.Sh SYNOPSIS 4486d7f5d3SJohn Marino.Cd pseudo-device vn Op n 4586d7f5d3SJohn Marino.Pp 4686d7f5d3SJohn MarinoAlternatively, to load the driver as a module at boot time, place the 4786d7f5d3SJohn Marinofollowing line in 4886d7f5d3SJohn Marino.Pa /boot/loader.conf : 4986d7f5d3SJohn Marino.Bd -literal -offset indent 5086d7f5d3SJohn Marinovn_load="YES" 5186d7f5d3SJohn Marino.Ed 5286d7f5d3SJohn Marino.Sh DESCRIPTION 5386d7f5d3SJohn MarinoThe 5486d7f5d3SJohn Marino.Nm 5586d7f5d3SJohn Marinodriver uses swap or a file as backing store to abstract-out a 5686d7f5d3SJohn Marinodevice which may then be used like a disk. 5786d7f5d3SJohn MarinoThe 5886d7f5d3SJohn Marino.Nm 5986d7f5d3SJohn Marinodriver supports both labeled and unlabeled pseudo-disks and is useful for 6086d7f5d3SJohn Marinoa variety of applications, including swap files and building mini-root, 6186d7f5d3SJohn Marinofloppy, or CD-ROM disk images. 6286d7f5d3SJohn Marino.Nm 6386d7f5d3SJohn Marinomay also be used to create temporary swap-backed filesystems, such as 6486d7f5d3SJohn Marino.Pa /tmp , 6586d7f5d3SJohn Marinoin a somewhat less memory-hungry manner than MFS. 6686d7f5d3SJohn Marino.Pp 6786d7f5d3SJohn MarinoThe 6886d7f5d3SJohn Marino.Nm 6986d7f5d3SJohn Marinodriver supports autocloning. By default 4 7086d7f5d3SJohn Marino.Nm 7186d7f5d3SJohn Marinodevices are also precreated. 7286d7f5d3SJohn Marino.Sh FILES 7386d7f5d3SJohn Marino.Bl -tag -width "Pa /dev/vn*" -compact 7486d7f5d3SJohn Marino.It Pa /dev/vn* 7586d7f5d3SJohn Marino.Nm 7686d7f5d3SJohn Marinodevice special files 7786d7f5d3SJohn Marino.El 7886d7f5d3SJohn Marino.Sh SEE ALSO 7986d7f5d3SJohn Marino.Xr fsck 8 , 8086d7f5d3SJohn Marino.Xr mount 8 , 8186d7f5d3SJohn Marino.Xr mount_mfs 8 , 8286d7f5d3SJohn Marino.Xr newfs 8 , 8386d7f5d3SJohn Marino.Xr vnconfig 8 8486d7f5d3SJohn Marino.Sh HISTORY 8586d7f5d3SJohn MarinoThe vnode disk driver was originally written at the University of 8686d7f5d3SJohn MarinoUtah and was substantially modified by 8786d7f5d3SJohn Marino.Fx 8886d7f5d3SJohn Marinodevelopers to add swap-backed support. 8986d7f5d3SJohn Marino.Sh BUGS 9086d7f5d3SJohn MarinoThe 9186d7f5d3SJohn Marino.Nm 9286d7f5d3SJohn Marinodriver does not work if the file does not reside in a local filesystem. 93