block-migration: fix block_save_iterate() return value

The .save_live_iterate() function returns 0 to continue iterating or 1
to stop iterating.

Since 16310a3 it only ever returns 0,
leading to an infinite loop.

Return 1 if we have finished sending dirty blocks.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1360534366-26723-4-git-send-email-stefanha@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

block-migration.c

@@ -582,7 +582,12 @@ static int block_save_iterate(QEMUFile *f, void *opaque)
 
     qemu_put_be64(f, BLK_MIG_FLAG_EOS);
 
-    return 0;
+    /* Complete when bulk transfer is done and all dirty blocks have been
+     * transferred.
+     */
+    return block_mig_state.bulk_completed &&
+           block_mig_state.submitted == 0 &&
+           block_mig_state.read_done == 0;
 }
 
 static int block_save_complete(QEMUFile *f, void *opaque)