Make D-Bus and udisks2 available early (#1291)

* Disable systemd-logind support for udisks2

Currently udisks2 uses systemd-logind to prevent the system from
rebooting or similar operations while udisks operations are ongoing.
Unfortunately this stops us from using udisks2 during early boot since
systemd-logind is not ready at this point. Make the dependency
configureable so we can opt-out of using systemd-logind.

* Make dbus.service/socket and udisks2.service/socket available early

Disable default dependencies. This avoids those services to be ordered
after sysinit.target, and makes them available before local-fs.target
is reached. All mounts like mnt-data.mount are ordered before
local-fs.target, so breaking this dependency allows to use D-Bus before
mounting local file systems.

This seems fine when using the system bus directly from /run (instead of
/var/run, which is anyway a symlink to /run normally). It seems that
udisks misses /var/lib/udisks2 but it seems not to be required for the
features used so far.

buildroot-external/package/udisks2/0001-Allow-to-explicitly-disable-libsystemd-login.patch

@@ -0,0 +1,51 @@
+From a00ce68f8b08abb925bf22c0c46858958dd93866 Mon Sep 17 00:00:00 2001
+Message-Id: <a00ce68f8b08abb925bf22c0c46858958dd93866.1616668703.git.stefan@agner.ch>
+From: Stefan Agner <stefan@agner.ch>
+Date: Thu, 25 Mar 2021 11:35:12 +0100
+Subject: [PATCH] Allow to explicitly disable libsystemd-login
+
+Currently libsystemd-login is used to inhibit poweroff, sleep and
+reboot. The library makes calls to systemd-logind which in turn needs
+quite some services to be present. This can be problematic when using
+udisks in early boot stages.
+---
+ configure.ac | 21 +++++++++++++--------
+ 1 file changed, 13 insertions(+), 8 deletions(-)
+
+diff --git a/configure.ac b/configure.ac
+index 53917998..0b3f0c9a 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -197,16 +197,21 @@ if test "x$enable_daemon" = "xyes"; then
+                 [AC_DEFINE([UUID_STR_LEN], 37, [compat UUID_STR_LEN define])],
+                 [[#include <uuid/uuid.h>]])
+ 
+-  PKG_CHECK_MODULES(LIBSYSTEMD_LOGIN, [libsystemd >= 209], [have_libsystemd_login=yes],
+-                    [PKG_CHECK_MODULES(LIBSYSTEMD_LOGIN, [libsystemd-login >= 44 libsystemd-daemon],
+-                    [have_libsystemd_login=yes],
+-                    [have_libsystemd_login=no])])
+-  if test "x$have_libsystemd_login" = "xyes"; then
+-    AC_DEFINE([HAVE_LIBSYSTEMD_LOGIN], 1, [Define to 1 if libsystemd-login is available])
++  have_libsystemd_login=no
++  AC_ARG_ENABLE(libsystemd-login, AS_HELP_STRING([--disable-libsystemd-login], [disable libsystemd-login support]))
++  if test "x$enable_libsystemd_login" != "xno"; then
++    PKG_CHECK_MODULES(LIBSYSTEMD_LOGIN, [libsystemd >= 209], [have_libsystemd_login=yes],
++                      [PKG_CHECK_MODULES(LIBSYSTEMD_LOGIN, [libsystemd-login >= 44 libsystemd-daemon],
++                      [have_libsystemd_login=yes],
++                      [have_libsystemd_login=no])])
++    if test "x$have_libsystemd_login" = "xyes"; then
++      AC_DEFINE([HAVE_LIBSYSTEMD_LOGIN], 1, [Define to 1 if libsystemd-login is available])
++    fi
++    AC_SUBST(LIBSYSTEMD_LOGIN_CFLAGS)
++    AC_SUBST(LIBSYSTEMD_LOGIN_LIBS)
+   fi
++  AM_CONDITIONAL([HAVE_LIBSYSTEMD_LOGIN], [test "x$have_libsystemd_login" = "xyes"])
+   AC_SUBST(HAVE_LIBSYSTEMD_LOGIN)
+-  AC_SUBST(LIBSYSTEMD_LOGIN_CFLAGS)
+-  AC_SUBST(LIBSYSTEMD_LOGIN_LIBS)
+ 
+   PKG_CHECK_MODULES(LIBELOGIND, [libelogind >= 219],
+                     [have_libelogind=yes],
+-- 
+2.30.2
+

buildroot-external/package/udisks2/udisks2.mk

@@ -25,7 +25,7 @@ UDISKS2_DEPENDENCIES = \
 	parted \
 	udev
 
-UDISKS2_CONF_OPTS = --disable-polkit --disable-man
+UDISKS2_CONF_OPTS = --disable-polkit --disable-man --disable-libsystemd-login
 
 ifeq ($(BR2_PACKAGE_GOBJECT_INTROSPECTION),y)
 UDISKS2_CONF_OPTS += --enable-introspection

buildroot-external/rootfs-overlay/etc/systemd/system/dbus.service.d/haos.conf

@@ -0,0 +1,2 @@
+[Unit]
+DefaultDependencies=no

buildroot-external/rootfs-overlay/etc/systemd/system/dbus.socket.d/haos.conf

@@ -0,0 +1,2 @@
+[Unit]
+DefaultDependencies=no

buildroot-external/rootfs-overlay/etc/systemd/system/udisks2.service.d/haos.conf

@@ -0,0 +1,5 @@
+[Unit]
+DefaultDependencies=no
+
+[Service]
+Environment="DBUS_SYSTEM_BUS_ADDRESS=unix:path=/run/dbus/system_bus_socket"

buildroot-external/rootfs-overlay/etc/systemd/system/udisks2.socket.d/haos.conf

@@ -0,0 +1,2 @@
+[Unit]
+DefaultDependencies=no