Let's introduce a lock for that QEMUFile since we are going to operate
on it in multiple threads.
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: NPeter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-23-peterx@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>