diff --git a/login1/dbus.go b/login1/dbus.go
index 8b85a32..90acc38 100644
--- a/login1/dbus.go
+++ b/login1/dbus.go
@@ -358,6 +358,10 @@ func (c *Conn) ScheduleShutdown(typ ScheduleShutdownType, when time.Time) {
 	c.object.Call(dbusManagerInterface+".ScheduleShutdown", 0, typ.String(), when.UnixMicro())
 }
 
+func (c *Conn) SetWallMessage(message string, enable bool) {
+	c.object.Call(dbusManagerInterface+".SetWallMessage", 0, message, enable)
+}
+
 // Inhibit takes inhibition lock in logind.
 func (c *Conn) Inhibit(what, who, why, mode string) (*os.File, error) {
 	var fd dbus.UnixFD
diff --git a/login1/types.go b/login1/types.go
index 7851b0b..6cda8f8 100644
--- a/login1/types.go
+++ b/login1/types.go
@@ -14,9 +14,15 @@ const (
 )
 
 const (
-	SD_LOGIND_ROOT_CHECK_INHIBITORS          = uint64(1) << 0
-	SD_LOGIND_KEXEC_REBOOT                   = uint64(1) << 1
+	// Request for weak inhibitors to apply to privileged users too.
+	SD_LOGIND_ROOT_CHECK_INHIBITORS = uint64(1) << 0
+	// Perform kexec reboot if a kexec kernel is loaded.
+	SD_LOGIND_KEXEC_REBOOT = uint64(1) << 1
+	// When SD_LOGIND_SOFT_REBOOT (0x04) is set, or SD_LOGIND_SOFT_REBOOT_IF_NEXTROOT_SET_UP
+	// (0x08) is set and a new root file system has been set up on "/run/nextroot/",
+	// then RebootWithFlags() performs a userspace reboot only.
 	SD_LOGIND_SOFT_REBOOT                    = uint64(1) << 2
 	SD_LOGIND_SOFT_REBOOT_IF_NEXTROOT_SET_UP = uint64(1) << 3
-	SD_LOGIND_SKIP_INHIBITORS                = uint64(1) << 4
+	// Skip all inhibitors.
+	SD_LOGIND_SKIP_INHIBITORS = uint64(1) << 4
 )