mapped-devices: Add 'lvm-device-mapping'.

* gnu/system/mapped-devices.scm (lvm-device-mapping, open-lvm-device,
close-lvm-device): New variables.

* gnu/tests/install.scm (%lvm-separate-home-os,
%lvm-separate-home-os-source, %lvm-separate-home-installation-script,
%test-lvm-separate-home-os): New variables.

* gnu/system/linux-initrd.scm (raw-initrd): Add (srfi srfi-1) to initrd expression.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

1 files changed, 23 insertions, 2 deletions

diff --git a/doc/guix.texi b/doc/guix.texi
index 13fb4b1531..22102972a3 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -13758,7 +13758,6 @@ Guix extends this notion by considering any device or set of devices that
 are @dfn{transformed} in some way to create a new device; for instance,
 RAID devices are obtained by @dfn{assembling} several other devices, such
 as hard disks or partitions, into a new one that behaves as one partition.
-Other examples, not yet implemented, are LVM logical volumes.
 
 Mapped devices are declared using the @code{mapped-device} form,
 defined as follows; for examples, see below.
@@ -13771,7 +13770,8 @@ the system boots up.
 @item source
 This is either a string specifying the name of the block device to be mapped,
 such as @code{"/dev/sda3"}, or a list of such strings when several devices
-need to be assembled for creating a new one.
+need to be assembled for creating a new one. In case of LVM this is a
+string specifying name of the volume group to be mapped.
 
 @item target
 This string specifies the name of the resulting mapped device.  For
@@ -13780,6 +13780,9 @@ specifying @code{"my-partition"} leads to the creation of
 the @code{"/dev/mapper/my-partition"} device.
 For RAID devices of type @code{raid-device-mapping}, the full device name
 such as @code{"/dev/md0"} needs to be given.
+LVM logical volumes of type @code{lvm-device-mapping} need to
+be specified as @code{"VGNAME-LVNAME"}.
+
 @item targets
 This list of strings specifies names of the resulting mapped devices in case
 there are several. The format is identical to @var{target}.
@@ -13803,6 +13806,11 @@ module for the appropriate RAID level to be loaded, such as @code{raid456}
 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
 @end defvr
 
+@defvr {Scheme Variable} lvm-device-mapping
+This defines LVM logical volume(s). Volume group is activated by
+@command{vgchange} command from the package @code{lvm2}.
+@end defvr
+
 @cindex disk encryption
 @cindex LUKS
 The following example specifies a mapping from @file{/dev/sda3} to
@@ -13860,6 +13868,19 @@ Note that the RAID level need not be given; it is chosen during the
 initial creation and formatting of the RAID device and is determined
 automatically later.
 
+LVM logical volumes ``alpha'' and ``beta'' from volume group ``vg0'' can
+be declared as follows:
+
+@lisp
+(mapped-device
+  (source "vg0")
+  (target (list "vg0-alpha" "vg0-beta"))
+  (type lvm-device-mapping))
+@end lisp
+
+Devices @file{/dev/mapper/vg0-alpha} and @file{/dev/mapper/vg0-beta} can
+then be used as the @code{device} of a @code{file-system} declaration
+(@pxref{File Systems}).
 
 @node User Accounts
 @section User Accounts