lxc: introduce virtlxcd daemon

The virtlxcd daemon will be responsible for providing the lxc API
driver functionality. The lxc driver is still loaded by the main
libvirtd daemon at this stage, so virtlxcd must not be running at
the same time.

Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

.gitignore

@@ -160,6 +160,9 @@
 /src/lxc/lxc_monitor_protocol.h
 /src/lxc/lxc_protocol.[ch]
 /src/lxc/test_libvirtd_lxc.aug
+/src/lxc/test_virtlxcd.aug
+/src/lxc/virtlxcd.aug
+/src/lxc/virtlxcd.conf
 /src/network/test_virtnetworkd.aug
 /src/network/virtnetworkd.aug
 /src/network/virtnetworkd.conf
@@ -198,6 +201,7 @@
 /src/virtxend
 /src/virtlockd
 /src/virtlogd
+/src/virtlxcd
 /src/virtnetworkd
 /src/virtnodedevd
 /src/virtnwfilterd

libvirt.spec.in

@@ -1760,6 +1760,14 @@ exit 0
 
 %if %{with_lxc}
 %files daemon-driver-lxc
+%config(noreplace) %{_sysconfdir}/libvirt/virtlxcd.conf
+%{_datadir}/augeas/lenses/virtlxcd.aug
+%{_datadir}/augeas/lenses/tests/test_virtlxcd.aug
+%{_unitdir}/virtlxcd.service
+%{_unitdir}/virtlxcd.socket
+%{_unitdir}/virtlxcd-ro.socket
+%{_unitdir}/virtlxcd-admin.socket
+%attr(0755, root, root) %{_sbindir}/virtlxcd
 %dir %attr(0700, root, root) %{_localstatedir}/log/libvirt/lxc/
 %config(noreplace) %{_sysconfdir}/libvirt/lxc.conf
 %config(noreplace) %{_sysconfdir}/logrotate.d/libvirtd.lxc

src/lxc/Makefile.inc.am

@@ -110,6 +110,69 @@ endif WITH_BLKID
 libvirt_driver_lxc_impl_la_LIBADD += $(SECDRIVER_LIBS)
 libvirt_driver_lxc_impl_la_SOURCES = $(LXC_DRIVER_SOURCES)
 
+
+sbin_PROGRAMS += virtlxcd
+
+nodist_conf_DATA += lxc/virtlxcd.conf
+augeas_DATA += lxc/virtlxcd.aug
+augeastest_DATA += lxc/test_virtlxcd.aug
+CLEANFILES += lxc/virtlxcd.aug
+
+virtlxcd_SOURCES = $(REMOTE_DAEMON_SOURCES)
+virtlxcd_CFLAGS = \
+       $(REMOTE_DAEMON_CFLAGS) \
+       -DDAEMON_NAME="\"virtlxcd\"" \
+       -DMODULE_NAME="\"lxc\"" \
+       $(NULL)
+virtlxcd_LDFLAGS = $(REMOTE_DAEMON_LD_FLAGS)
+virtlxcd_LDADD = $(REMOTE_DAEMON_LD_ADD)
+
+SYSTEMD_UNIT_FILES += \
+	virtlxcd.service \
+	virtlxcd.socket \
+	virtlxcd-ro.socket \
+	virtlxcd-admin.socket \
+	$(NULL)
+SYSTEMD_UNIT_FILES_IN += \
+	lxc/virtlxcd.service.in \
+	$(NULL)
+
+VIRTLXCD_UNIT_VARS = \
+	$(VIRTD_UNIT_VARS) \
+	-e 's|[@]name[@]|Libvirt lxc|g' \
+	-e 's|[@]service[@]|virtlxcd|g' \
+	-e 's|[@]sockprefix[@]|virtlxcd|g' \
+	$(NULL)
+
+virtlxcd.service: lxc/virtlxcd.service.in $(top_builddir)/config.status
+	$(AM_V_GEN)$(SED) $(VIRTLXCD_UNIT_VARS) $< > $@-t && mv $@-t $@
+
+virtlxc%.socket: remote/libvirt%.socket.in $(top_builddir)/config.status
+	$(AM_V_GEN)$(SED) $(VIRTLXCD_UNIT_VARS) $< > $@-t && mv $@-t $@
+
+lxc/virtlxcd.conf: remote/libvirtd.conf.in
+	$(AM_V_GEN)$(SED) \
+		-e '/[@]CUT_ENABLE_IP[@]/,/[@]END[@]/d' \
+		-e 's/[@]DAEMON_NAME[@]/virtlxcd/' \
+		$< > $@
+
+lxc/virtlxcd.aug: remote/libvirtd.aug.in
+	$(AM_V_GEN)$(SED) \
+		-e '/[@]CUT_ENABLE_IP[@]/,/[@]END[@]/d' \
+		-e 's/[@]DAEMON_NAME[@]/virtlxcd/' \
+		-e 's/[@]DAEMON_NAME_UC[@]/Virtlxcd/' \
+		$< > $@
+
+lxc/test_virtlxcd.aug: remote/test_libvirtd.aug.in \
+		lxc/virtlxcd.conf $(AUG_GENTEST)
+	$(AM_V_GEN)$(AUG_GENTEST) lxc/virtlxcd.conf \
+		$(srcdir)/remote/test_libvirtd.aug.in | \
+		$(SED) \
+		-e '/[@]CUT_ENABLE_IP[@]/,/[@]END[@]/d' \
+		-e 's/[@]DAEMON_NAME[@]/virtlxcd/' \
+		-e 's/[@]DAEMON_NAME_UC[@]/Virtlxcd/' \
+		> $@ || rm -f $@
+
 libexec_PROGRAMS += libvirt_lxc
 
 libvirt_lxc_SOURCES = \

src/lxc/virtlxcd.service.in

@@ -0,0 +1,40 @@
+[Unit]
+Description=Virtualization lxc daemon
+Conflicts=libvirtd.service
+Requires=virtlxcd.socket
+Requires=virtlxcd-ro.socket
+Requires=virtlxcd-admin.socket
+Wants=systemd-machined.service
+Before=libvirt-guests.service
+After=network.target
+After=dbus.service
+After=apparmor.service
+After=local-fs.target
+After=remote-fs.target
+After=systemd-logind.service
+After=systemd-machined.service
+Documentation=man:libvirtd(8)
+Documentation=https://libvirt.org
+
+[Service]
+Type=notify
+ExecStart=@sbindir@/virtlxcd --timeout 120
+ExecReload=/bin/kill -HUP $MAINPID
+KillMode=process
+Restart=on-failure
+# At least 1 FD per guest, often 2 (eg qemu monitor + qemu agent).
+# eg if we want to support 4096 guests, we'll typically need 8192 FDs
+# If changing this, also consider virtlogd.service & virtlockd.service
+# limits which are also related to number of guests
+LimitNOFILE=8192
+# The cgroups pids controller can limit the number of tasks started by
+# the daemon, which can limit the number of domains for some hypervisors.
+# A conservative default of 8 tasks per guest results in a TasksMax of
+# 32k to support 4096 guests.
+TasksMax=32768
+
+[Install]
+WantedBy=multi-user.target
+Also=virtlxcd.socket
+Also=virtlxcd-ro.socket
+Also=virtlxcd-admin.socket