6581 cmd/format should be able label virtio BLKDEV drives
Reviewed by: Hans Rosenfeld <hans.rosenfeld@nexenta.com>
Reviewed by: Toomas Soome <tsoome@me.com>

@@ -21,10 +21,11 @@
 /*
  * Copyright (c) 1993, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright 2012 Milan Jurik. All rights reserved.
  * Copyright 2014 Toomas Soome <tsoome@me.com>
  * Copyright 2015 Nexenta Systems, Inc. All rights reserved.
+ * Copyright 2016 Igor Kozhukhov <ikozhukhov@gmail.com>
  */
 
 /*
  * This file contains functions that implement the command menu commands.
  */

@@ -1619,11 +1620,12 @@
 #endif
 
                 (void) memset((char *)&label, 0, sizeof (struct dk_label));
 
                 (void) strcpy(x86_devname, cur_disk->disk_name);
-                if (cur_ctype->ctype_ctype == DKC_DIRECT)
+                if (cur_ctype->ctype_ctype == DKC_DIRECT ||
+                    cur_ctype->ctype_ctype == DKC_BLKDEV)
                         dptr = auto_direct_get_geom_label(cur_file,  &label);
                 else
                         dptr = auto_sense(cur_file, 1, &label);
                 if (dptr == NULL) {
                         fmt_print("Autoconfiguration failed.\n");