[systemd-devel] [PATCH 2/2] initrd: add unit files needed for basic systemd-in-initrd support

[Lennart Poettering]

On Mon, 25.02.13 16:00, Tom Gundersen (teg at jklm.no) wrote:

Two of the units definitely sound like good stuff to have in
systemd. But let's first discuss the fstab.sys issue. I am not convinced
about that one. Would still prefer to simply have root= and usr= on the
kernel cmdline and live without fstab.sys...

> This will:
>  * mount all configured filesystems (typically the rootfs on /sysroot)
>  * reload the configuration to pick up anything from the mounted fs (typically
>    /sysroot/etc/fstab.sys)
>  * mount any newly configured filesystems (typically /usr on /sysroot/usr, if
>    applicable)
>  * shut-down and clean-up any daemons running in the initramfs (typically udevd)
>  * switch-root to /sysroot and start the real init


> 
> Cc: Harald Hoyer <harald.hoyer at gmail.com>
> Cc: Dave Reisner <d at falconindy.com>
> ---
>  Makefile.am                             |  7 ++++++-
>  units/initrd-cleanup.service            | 18 ++++++++++++++++++
>  units/initrd-parse-etc.service          | 19 +++++++++++++++++++
>  units/initrd-switch-root.service        | 19 +++++++++++++++++++
>  units/initrd-switch-root.target         | 16 ++++++++++++++++
>  units/initrd-udevadm-cleanup-db.service | 18 ++++++++++++++++++
>  6 files changed, 96 insertions(+), 1 deletion(-)
>  create mode 100644 units/initrd-cleanup.service
>  create mode 100644 units/initrd-parse-etc.service
>  create mode 100644 units/initrd-switch-root.service
>  create mode 100644 units/initrd-switch-root.target
>  create mode 100644 units/initrd-udevadm-cleanup-db.service
> 
> diff --git a/Makefile.am b/Makefile.am
> index f0f0ebc..aa2164c 100644
> --- a/Makefile.am
> +++ b/Makefile.am
> @@ -373,7 +373,12 @@ dist_systemunit_DATA = \
>  	units/systemd-ask-password-console.path \
>  	units/systemd-udevd-control.socket \
>  	units/systemd-udevd-kernel.socket \
> -	units/system-update.target
> +	units/system-update.target \
> +	units/initrd-parse-etc.service \
> +	units/initrd-cleanup.service \
> +	units/initrd-switch-root.target \
> +	units/initrd-udevadm-cleanup-db.service \
> +	units/initrd-switch-root.service
>  
>  nodist_systemunit_DATA = \
>  	units/getty at .service \
> diff --git a/units/initrd-cleanup.service b/units/initrd-cleanup.service
> new file mode 100644
> index 0000000..8998696
> --- /dev/null
> +++ b/units/initrd-cleanup.service
> @@ -0,0 +1,18 @@
> +#  This file is part of systemd.
> +#
> +#  systemd is free software; you can redistribute it and/or modify it
> +#  under the terms of the GNU Lesser General Public License as published by
> +#  the Free Software Foundation; either version 2.1 of the License, or
> +#  (at your option) any later version.
> +
> +[Unit]
> +Description=Cleaning Up and Shutting Down Daemons
> +DefaultDependencies=no
> +ConditionPathExists=/etc/initrd-release
> +OnFailure=emergency.target
> +Requires=local-fs.target swap.target
> +After=local-fs.target swap.target
> +
> +[Service]
> +Type=oneshot
> +ExecStart=/usr/bin/systemctl --no-block isolate initrd-switch-root.target
> diff --git a/units/initrd-parse-etc.service b/units/initrd-parse-etc.service
> new file mode 100644
> index 0000000..4bfbb0f
> --- /dev/null
> +++ b/units/initrd-parse-etc.service
> @@ -0,0 +1,19 @@
> +#  This file is part of systemd.
> +#
> +#  systemd is free software; you can redistribute it and/or modify it
> +#  under the terms of the GNU Lesser General Public License as published by
> +#  the Free Software Foundation; either version 2.1 of the License, or
> +#  (at your option) any later version.
> +
> +[Unit]
> +Description=Reload Configuration from the Real Root
> +DefaultDependencies=no
> +Requires=local-fs.target swap.target
> +After=local-fs.target swap.target
> +OnFailure=emergency.target
> +ConditionPathExists=/etc/initrd-release
> +
> +[Service]
> +Type=oneshot
> +ExecStartPre=/usr/bin/systemctl daemon-reload
> +ExecStart=/usr/bin/systemctl --no-block start initrd-cleanup.service
> diff --git a/units/initrd-switch-root.service b/units/initrd-switch-root.service
> new file mode 100644
> index 0000000..e076b39
> --- /dev/null
> +++ b/units/initrd-switch-root.service
> @@ -0,0 +1,19 @@
> +#  This file is part of systemd.
> +#
> +#  systemd is free software; you can redistribute it and/or modify it
> +#  under the terms of the GNU Lesser General Public License as published by
> +#  the Free Software Foundation; either version 2.1 of the License, or
> +#  (at your option) any later version.
> +
> +[Unit]
> +Description=Switch Root
> +DefaultDependencies=no
> +ConditionPathExists=/etc/initrd-release
> +OnFailure=emergency.target
> +AllowIsolate=yes
> +
> +[Service]
> +Type=oneshot
> +# we have to use "--force" here, otherwise systemd would umount /run
> +ExecStart=/usr/bin/systemctl --no-block --force switch-root /sysroot
> +KillMode=none
> diff --git a/units/initrd-switch-root.target b/units/initrd-switch-root.target
> new file mode 100644
> index 0000000..f706d29
> --- /dev/null
> +++ b/units/initrd-switch-root.target
> @@ -0,0 +1,16 @@
> +#  This file is part of systemd.
> +#
> +#  systemd is free software; you can redistribute it and/or modify it
> +#  under the terms of the GNU Lesser General Public License as published by
> +#  the Free Software Foundation; either version 2.1 of the License, or
> +#  (at your option) any later version.
> +
> +[Unit]
> +Description=Switch Root
> +ConditionPathExists=/etc/initrd-release
> +DefaultDependencies=no
> +Requires=initrd-switch-root.service
> +Before=initrd-switch-root.service
> +AllowIsolate=yes
> +Wants=initrd-udevadm-cleanup-db.service local-fs.target swap.target systemd-journald.service
> +After=initrd-udevadm-cleanup-db.service local-fs.target swap.target emergency.service emergency.target
> diff --git a/units/initrd-udevadm-cleanup-db.service b/units/initrd-udevadm-cleanup-db.service
> new file mode 100644
> index 0000000..983189e
> --- /dev/null
> +++ b/units/initrd-udevadm-cleanup-db.service
> @@ -0,0 +1,18 @@
> +#  This file is part of systemd.
> +#
> +#  systemd is free software; you can redistribute it and/or modify it
> +#  under the terms of the GNU Lesser General Public License as published by
> +#  the Free Software Foundation; either version 2.1 of the License, or
> +#  (at your option) any later version.
> +
> +[Unit]
> +Description=Cleanup udevd DB
> +DefaultDependencies=no
> +ConditionPathExists=/etc/initrd-release
> +Conflicts=systemd-udevd.service systemd-udevd-control.socket systemd-udevd-kernel.socket
> +After=systemd-udevd.service systemd-udevd-control.socket systemd-udevd-kernel.socket
> +Before=initrd-switch-root.target
> +
> +[Service]
> +Type=oneshot
> +ExecStart=-/usr/bin/udevadm info --cleanup-db


Lennart

-- 
Lennart Poettering - Red Hat, Inc.