[RFC PATCH 3/5] migration: Add cleanup hook for inwards migration

["Dr. David Alan Gilbert (git)" <dgilbert@redhat.com>]

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

Add a cleanup hook for incoming migration that gets called
at the end as a way for a transport to allow cleanup.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 migration/migration.c | 3 +++
 migration/migration.h | 4 ++++
 2 files changed, 7 insertions(+)

diff --git a/migration/migration.c b/migration/migration.c
index ca8b97baa5..feaedc382e 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -279,6 +279,9 @@ void migration_incoming_state_destroy(void)
         g_array_free(mis->postcopy_remote_fds, TRUE);
         mis->postcopy_remote_fds = NULL;
     }
+    if (mis->transport_cleanup) {
+        mis->transport_cleanup(mis->transport_data);
+    }
 
     qemu_event_reset(&mis->main_thread_load_event);
 
diff --git a/migration/migration.h b/migration/migration.h
index db6708326b..1b4c5da917 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -49,6 +49,10 @@ struct PostcopyBlocktimeContext;
 struct MigrationIncomingState {
     QEMUFile *from_src_file;
 
+    /* A hook to allow cleanup at the end of incoming migration */
+    void *transport_data;
+    void (*transport_cleanup)(void *data);
+
     /*
      * Free at the start of the main state load, set as the main thread finishes
      * loading state.
-- 
2.31.1