Merge pull request #2162 from lolyu/rebase_support_block_device

commit_snapshot_to_raw_backing: add switch for size check 

qemu/tests/cfg/commit_snapshot_to_raw_backing.cfg

@@ -21,6 +21,7 @@
     dd_total_size = "${dd_bs_val} * ${dd_bs_count} * 1024 ** 2"
     file_create_cmd = "dd if=/dev/urandom of=%s bs=${dd_bs_val}M count=${dd_bs_count}"
     guest_file_name = ${tmp_file_name}
+    snapshot_size_check_after_commit = yes
     Windows:
         guest_file_name = C:\testfile
         x86_64:

qemu/tests/commit_snapshot_to_raw_backing.py

@@ -82,11 +82,15 @@ def run(test, params, env):
     else:
         logging.info("Commit snapshot image %s back to %s.", snapshot, base)
 
+    size_check = params.get("snapshot_size_check_after_commit") == "yes"
+    if size_check:
         org_size = json.loads(sn_img.info(output="json"))["actual-size"]
     sn_img.commit(cache_mode=cache_mode)
+
+    if size_check:
         remain_size = json.loads(sn_img.info(output="json"))["actual-size"]
 
-    """Verify the snapshot file whether emptied after committing"""
+        # Verify the snapshot file whether emptied after committing
         logging.info("Verify the snapshot file whether emptied after committing")
         commit_size = org_size - remain_size
         dd_size = eval(params["dd_total_size"])