[PATCH 24/33] Generate fallback mount unit for root filesystem

Thomas Renninger
2014-11-20T14:56:59Z

From: Thorsten Behrens <tbehrens-IBi9RG/b67k@public.gmane.org>

If kernel cmdline has no root= provided, *and* the initrd carries
a default value, create a systemd mount unit to have it available
in /sysroot

References: bnc#855258

Signed-off-by: Thorsten Behrens <tbehrens-IBi9RG/b67k@public.gmane.org>
Signed-off-by: Thomas Renninger <trenn-l3A5Bk7waGM@public.gmane.org>
---
modules.d/98systemd/rootfs-generator.sh | 34 ++++++++++++++++++++++++++++++++-
1 file changed, 33 insertions(+), 1 deletion(-)

diff --git a/modules.d/98systemd/rootfs-generator.sh b/modules.d/98systemd/rootfs-generator.sh
index 5b06137..f3c7d1f 100755
--- a/modules.d/98systemd/rootfs-generator.sh
+++ b/modules.d/98systemd/rootfs-generator.sh
@@ -35,6 +35,35 @@ generator_wait_for_dev()
fi
}

+generator_mount_rootfs()
+{
+ local _type=$2
+ local _flags=$3
+ local _name
+
+ [ -z "$1" ] && return 0
+
+ _name=$(dev_unit_name "$1")
+ [ -d /run/systemd/generator ] || mkdir -p /run/systemd/generator
+ if ! [ -f /run/systemd/generator/sysroot.mount ]; then
+ {
+ echo "[Unit]"
+ echo "Before=initrd-root-fs.target"
+ echo "RequiresOverridable=systemd-fsck@${_name}.service"
+ echo "After=systemd-fsck@${_name}.service"
+ echo "[Mount]"
+ echo "Where=/sysroot"
+ echo "What=$1"
+ echo "Options=${_flags}"
+ echo "Type=${_type}"
+ } > /run/systemd/generator/sysroot.mount
+ fi
+ if ! [ -L /run/systemd/generator/initrd-root-fs.target.requires/sysroot.mount ]; then
+ [ -d /run/systemd/generator/initrd-root-fs.target.requires ] || mkdir -p /run/systemd/generator/initrd-root-fs.target.requires
+ ln -s ../sysroot.mount /run/systemd/generator/initrd-root-fs.target.requires/sysroot.mount
+ fi
+}
+
root=$(getarg root=)
case "$root" in
block:LABEL=*|LABEL=*)
@@ -61,6 +90,9 @@ case "$root" in
rootok=1 ;;
esac

-[ "${root%%:*}" = "block" ] && generator_wait_for_dev "${root#block:}" "$RDRETRY"
+if [ "${root%%:*}" = "block" ]; then
+ generator_wait_for_dev "${root#block:}" "$RDRETRY"
+ grep -q 'root=' /proc/cmdline || generator_mount_rootfs "${root#block:}" "$(getarg rootfstype=)" "$(getarg rootflags=)"
+fi

exit 0
--
1.8.5.2