Add ignition-subsequent.target for non-Ignition boots

dracut/30ignition/ignition-generator

@@ -53,6 +53,12 @@ Requires=dev-disk-by\x2dlabel-boot.device
 After=dev-disk-by\x2dlabel-boot.device
 EOF
     fi
+else
+    # If we're doing a non-Ignition (subsequent) boot, then
+    # queue a different target.  This is necessary so that units
+    # like `ignition-ostree-mount-sysroot.service`
+    # can cleanly distinguish between the two.
+    add_requires ignition-subsequent.target initrd.target
 fi
 
 echo "PLATFORM_ID=$(cmdline_arg ignition.platform.id)" > /run/ignition.env

dracut/30ignition/ignition-subsequent.target

@@ -0,0 +1,14 @@
+# This target is queued to run when Ignition will *not* run.
+# It's intended right now for mounting sysroot, which happens in a quite
+# different order on the Ignition boot versus "subsequent" boots.
+[Unit]
+Description=Subsequent (Not Ignition) boot complete
+Before=initrd.target
+
+# See comments in ignition-complete.target
+OnFailure=emergency.target
+OnFailureJobMode=isolate
+
+# Make sure we stop all the units before switching root
+Conflicts=initrd-switch-root.target umount.target
+Conflicts=dracut-emergency.service emergency.service emergency.target

dracut/30ignition/module-setup.sh

@@ -54,6 +54,8 @@ install() {
 
     inst_simple "$moddir/ignition-complete.target" \
         "$systemdsystemunitdir/ignition-complete.target"
+    inst_simple "$moddir/ignition-subsequent.target" \
+        "$systemdsystemunitdir/ignition-subsequent.target"
 
     inst_simple "$moddir/ignition-diskful.target" \
         "$systemdsystemunitdir/ignition-diskful.target"