diff --git a/share/man/man4/dm.4 b/share/man/man4/dm.4 index 41fc2f73fc27..65c57250086a 100644 --- a/share/man/man4/dm.4 +++ b/share/man/man4/dm.4 @@ -1,4 +1,4 @@ -.\" $NetBSD: dm.4,v 1.1 2008/12/22 02:28:28 haad Exp $ +.\" $NetBSD: dm.4,v 1.2 2008/12/22 08:52:37 wiz Exp $ .\" .\" Copyright (c) 1996, 1997 The NetBSD Foundation, Inc. .\" All rights reserved. @@ -38,81 +38,104 @@ The .Nm driver provides the capability of creating one or more virtual disks -based on target mapping. +based on the target mapping. .Pp -This document assumes that you're familiar with how to generate kernels, -how to properly configure disks and pseudo-devices in a kernel configuration file, -and how to partition disks. This driver is used by linux lvm2tools to create/manage -lvm in NetBSD. +This document assumes that you're familiar with how to generate +kernels, how to properly configure disks and pseudo-devices in a +kernel configuration file, and how to partition disks. +This driver is used by the Linux lvm2tools to create and manage +lvm in +.Nx . .Pp -Note that there are -.Pa linear, zero, error -targets implemented now. -Each component partition should be offset at least 2 sectors +Currently, the +.Pa linear , zero , +and +.Pa error +targets are implemented. +Each component partition should be offset at least 2 sectors from the beginning of the component disk. This avoids potential conflicts between the component disk's -disklabel and the -.Nm Ns 's +disklabel and +.Nm Ap s disklabel. -In i386 it is offset 65s. Where 63 sectors are initial boot -sectors and 2 sectors are used for disklabel which is set to -be read-only. +In i386 it is offset by 65 sectors, where 63 sectors are the initial +boot sectors and 2 sectors are used for the disklabel which is set +to be read-only. .Pp -In order to compile in support for the +In order to compile in support for .Nm , -you must add a line similar -to the following to your kernel configuration file: +you must add a line similar to the following to your kernel +configuration file: .Bd -unfilled -offset indent pseudo-device dm #device-mapper disk device .Ed .Pp -A .Nm -may create linear mapped devices, zero and error block devices. Zero -and error block devices are used mostly for testing. -.Pa Linear -devices are used to create Virtual disks with lineary mapped virtual blocks -to blocks on real disk. +may create linear mapped devices, zero, and error block devices. +Zero and error block devices are used mostly for testing. +.Pa Linear +devices are used to create virtual disks with linearly mapped virtual +blocks to blocks on real disk. .Nm -Device-mapper devices are controlled throught /dev/mapper/control device. For -controlling this device Ioctl calls are used. For implementation of communication -channel proplib library is used. Protocol channel is defined as on proplib -dictionary with needed values. For more reference look at sys/dev/dm/netbsd-dm.h. -.Nm -Before any device can be used every device-mapper disk device must be initialized. -For initialization is needed to pass one line to kernel driver in a form of proplib -dictionary. Every device can have more than one tables active. +Device-mapper devices are controlled through the +.Pa /dev/mapper/control +device. +For controlling this device +.Xr ioctl 2 +calls are used. +For the implementation of the communication channel, +the +.Xr proplib 3 +library is used. +The protocol channel is defined as a proplib dictionary with needed +values. +For more details, look at +.Pa sys/dev/dm/netbsd-dm.h . +Before any device can be used, every device-mapper disk device must +be initialized. +For initialization one line must be passed to the kernel driver in +the form of a proplib dictionary. +Every device can have more than one table active. +An example for such a line is: .Bd -unfilled -offset indent 0 10240 linear /dev/wd1a 384 .Ed .Pp .Nm -The first parameter is start sector for table defined with this line, the second is length in -sectors which is described with this table. The third parameter is target name. All other parts -of this line depends on choosen target. +The first parameter is the start sector for the table defined with +this line, the second is the length in sectors which is described +with this table. +The third parameter is the target name. +All other parts of this line depend on the chosen target. .Nm -For linear target there are two additional parameters the first parameter describes disk device -on which device-mapper disk is mapped. The second parameter is offset on this disk from start of -disk/partition. -.Sh WARNINGS - This driver is still work-in-progress there can be bugs. -.Sh AUTHORS -.An Adam Hamsik Aq haad@NetBSD.org -implemented the device-mapper driver -.Nx . -.Pp -.An Brett Blymn Aq blymn@NetBSD.org , -.An Reinoud Zandijk Aq reinoud@netbsd.org and -.An Bill Stouder-Studenmund Aq wrstuden@netbsd.org -provided guidance and answered questions about NetBSD implementation. +For the linear target, there are two additional parameters: +The first parameter describes the disk device to which the +device-mapper disk is mapped. +The second parameter is the offset on this disk from the start of +the disk/partition. .Sh SEE ALSO .Xr config 1 , +.Xr proplib 3 , .Xr MAKEDEV 8 , -.Xr lvm 8 , .Xr dmsetup 8 , .Xr fsck 8 , +.Xr lvm 8 , .Xr mount 8 , -.Xr newfs 8 , -.Xr proplib 3 +.Xr newfs 8 .Sh HISTORY -The device-mapper disk driver first appeared in NetBSD 6.0. +The device-mapper disk driver first appeared in +.Nx 6.0 . +.Sh AUTHORS +.An Adam Hamsik Aq haad@NetBSD.org +implemented the device-mapper driver for +.Nx . +.Pp +.An Brett Blymn Aq blymn@NetBSD.org , +.An Reinoud Zandijk Aq reinoud@NetBSD.org , +and +.An Bill Stouder-Studenmund Aq wrstuden@NetBSD.org +provided guidance and answered questions about the +.Nx +implementation. +.Sh BUGS +This driver is still work-in-progress\(emthere can be bugs.