CP-308455 VM.sysprep CA-414158 wait for "action" key to disappear (xapi-project#6604)

Eject CD once sysprep is no longer running. This moves it to an earlier
point to avoid we try to eject the CD when the VM is rebooting and is
not cooperating.

Signed-off-by: Christian Lindig <christian.lindig@cloud.com>

Author: lindig

ocaml/xapi/vm_sysprep.ml

@@ -206,9 +206,18 @@ let find_vdi ~__context ~label =
       warn "%s: more than one VDI with label %s" __FUNCTION__ label ;
       vdi
 
+(* Ejecting the CD/VDI/ISO may fail with a timeout *)
+let eject ~rpc ~session_id ~vbd ~iso =
+  try
+    Client.VBD.eject ~rpc ~session_id ~vbd ;
+    Sys.remove iso
+  with exn ->
+    debug "%s: ejecting CD failed: %s" __FUNCTION__ (Printexc.to_string exn) ;
+    fail VM_CDR_eject
+
 (** notify the VM with [domid] to run sysprep and where to find the
     file. *)
-let trigger ~domid ~uuid ~timeout =
+let trigger ~rpc ~session_id ~domid ~uuid ~timeout ~vbd ~iso =
   let open Ezxenstore_core.Xenstore in
   let control = Printf.sprintf "/local/domain/%Ld/control/sysprep" domid in
   let domain = Printf.sprintf "/local/domain/%Ld" domid in
@@ -228,19 +237,15 @@ let trigger ~domid ~uuid ~timeout =
         Ezxenstore_core.Watch.(
           wait_for ~xs ~timeout (key_to_disappear (control // "action"))
         ) ;
-        debug "%s sysprep is finished" __FUNCTION__ ;
+        debug "%s sysprep is finished; ejecting CD" __FUNCTION__ ;
+        eject ~rpc ~session_id ~vbd ~iso ;
         Ezxenstore_core.Watch.(wait_for ~xs ~timeout (key_to_disappear domain)) ;
         true
       with Ezxenstore_core.Watch.Timeout _ ->
         debug "%s: sysprep timeout" __FUNCTION__ ;
         false
   )
 
-(* Ejecting the CD/VDI/ISO may fail with a timeout *)
-let eject ~rpc ~session_id iso vbd =
-  Client.VBD.eject ~rpc ~session_id ~vbd ;
-  Sys.remove iso
-
 (* This function is executed on the host where [vm] is running *)
 let sysprep ~__context ~vm ~unattend ~timeout =
   debug "%s (timeout %f)" __FUNCTION__ timeout ;
@@ -275,19 +280,8 @@ let sysprep ~__context ~vm ~unattend ~timeout =
   call ~__context @@ fun rpc session_id ->
   Client.VBD.insert ~rpc ~session_id ~vdi ~vbd ;
   Thread.delay !Xapi_globs.vm_sysprep_wait ;
-  match trigger ~domid ~uuid ~timeout with
-  | true -> (
-      debug "%s: sysprep running, ejecting CD" __FUNCTION__ ;
-      try eject ~rpc ~session_id iso vbd
-      with exn ->
-        debug "%s: ejecting CD failed: %s" __FUNCTION__ (Printexc.to_string exn) ;
-        fail VM_CDR_eject
-    )
+  match trigger ~rpc ~session_id ~domid ~uuid ~timeout ~vbd ~iso with
+  | true ->
+      ()
   | false ->
-      debug "%s: sysprep timeout, ejecting CD" __FUNCTION__ ;
-      ( try eject ~rpc ~session_id iso vbd
-        with exn ->
-          debug "%s: ejecting CD failed: %s" __FUNCTION__
-            (Printexc.to_string exn)
-      ) ;
       fail VM_sysprep_timeout