blockdev: Overlays are not snapshots

There are error messages which refer to an overlay node as the snapshot.
That is wrong, those are two different things.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20190603202236.1342-3-mreitz@redhat.com
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>

blockdev.c

@@ -1608,13 +1608,13 @@ static void external_snapshot_prepare(BlkActionState *common,
             s->has_snapshot_node_name ? s->snapshot_node_name : NULL;
 
         if (node_name && !snapshot_node_name) {
-            error_setg(errp, "New snapshot node name missing");
+            error_setg(errp, "New overlay node name missing");
             goto out;
         }
 
         if (snapshot_node_name &&
             bdrv_lookup_bs(snapshot_node_name, snapshot_node_name, NULL)) {
-            error_setg(errp, "New snapshot node name already in use");
+            error_setg(errp, "New overlay node name already in use");
             goto out;
         }
 
@@ -1656,7 +1656,7 @@ static void external_snapshot_prepare(BlkActionState *common,
     }
 
     if (bdrv_has_blk(state->new_bs)) {
-        error_setg(errp, "The snapshot is already in use");
+        error_setg(errp, "The overlay is already in use");
         goto out;
     }
 
@@ -1666,12 +1666,12 @@ static void external_snapshot_prepare(BlkActionState *common,
     }
 
     if (state->new_bs->backing != NULL) {
-        error_setg(errp, "The snapshot already has a backing image");
+        error_setg(errp, "The overlay already has a backing image");
         goto out;
     }
 
     if (!state->new_bs->drv->supports_backing) {
-        error_setg(errp, "The snapshot does not support backing images");
+        error_setg(errp, "The overlay does not support backing images");
         goto out;
     }
 

tests/qemu-iotests/085.out

@@ -64,13 +64,13 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file=TEST_DIR/
 
 === Invalid command - cannot create a snapshot using a file BDS ===
 
-{"error": {"class": "GenericError", "desc": "The snapshot does not support backing images"}}
+{"error": {"class": "GenericError", "desc": "The overlay does not support backing images"}}
 
 === Invalid command - snapshot node used as active layer ===
 
-{"error": {"class": "GenericError", "desc": "The snapshot is already in use"}}
-{"error": {"class": "GenericError", "desc": "The snapshot is already in use"}}
-{"error": {"class": "GenericError", "desc": "The snapshot is already in use"}}
+{"error": {"class": "GenericError", "desc": "The overlay is already in use"}}
+{"error": {"class": "GenericError", "desc": "The overlay is already in use"}}
+{"error": {"class": "GenericError", "desc": "The overlay is already in use"}}
 
 === Invalid command - snapshot node used as backing hd ===
 
@@ -81,7 +81,7 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file=TEST_DIR/
 Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=134217728
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file=TEST_DIR/t.IMGFMT.base
 {"return": {}}
-{"error": {"class": "GenericError", "desc": "The snapshot already has a backing image"}}
+{"error": {"class": "GenericError", "desc": "The overlay already has a backing image"}}
 
 === Invalid command - The node does not exist ===