iotests: 257: drop unused Drive.device field

After previous commit Drive.device is actually unused. Drop it together
with .name property.  While being here reuse .node in qmp commands
instead of writing 'drive0' twice.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190920142056.12778-11-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

tests/qemu-iotests/257

@@ -148,11 +148,6 @@ class Drive:
         self.fmt = None
         self.size = None
         self.node = None
-        self.device = None
-
-    @property
-    def name(self):
-        return self.node or self.device
 
     def img_create(self, fmt, size):
         self.fmt = fmt
@@ -201,7 +196,7 @@ def blockdev_backup(vm, device, target, sync, **kwargs):
 def blockdev_backup_mktarget(drive, target_id, filepath, sync, **kwargs):
     target_drive = Drive(filepath, vm=drive.vm)
     target_drive.create_target(target_id, drive.fmt, drive.size)
-    blockdev_backup(drive.vm, drive.name, target_id, sync, **kwargs)
+    blockdev_backup(drive.vm, drive.node, target_id, sync, **kwargs)
 
 def reference_backup(drive, n, filepath):
     log("--- Reference Backup #{:d} ---\n".format(n))
@@ -229,7 +224,7 @@ def perform_writes(drive, n):
             pattern.offset,
             pattern.size)
         log(cmd)
-        log(drive.vm.hmp_qemu_io(drive.name, cmd))
+        log(drive.vm.hmp_qemu_io(drive.node, cmd))
     bitmaps = drive.vm.query_bitmaps()
     log({'bitmaps': bitmaps}, indent=2)
     log('')
@@ -324,26 +319,25 @@ def test_bitmap_sync(bsync_mode, msync_mode='bitmap', failure=None):
                 }]
             }
 
+        drive0.node = 'drive0'
         vm.qmp_log('blockdev-add',
                    filters=[iotests.filter_qmp_testfiles],
-                   node_name="drive0",
+                   node_name=drive0.node,
                    driver=drive0.fmt,
                    file=file_config)
-        drive0.node = 'drive0'
-        drive0.device = 'device0'
         # Use share-rw to allow writes directly to the node;
         # The anonymous block-backend for this configuration prevents us
         # from using HMP's qemu-io commands to address the device.
-        vm.qmp_log("device_add", id=drive0.device,
-                   drive=drive0.name, driver="scsi-hd",
+        vm.qmp_log("device_add", id='device0',
+                   drive=drive0.node, driver="scsi-hd",
                    share_rw=True)
         log('')
 
         # 0 - Writes and Reference Backup
         perform_writes(drive0, 0)
         reference_backup(drive0, 0, fbackup0)
         log('--- Add Bitmap ---\n')
-        vm.qmp_log("block-dirty-bitmap-add", node=drive0.name,
+        vm.qmp_log("block-dirty-bitmap-add", node=drive0.node,
                    name="bitmap0", granularity=GRANULARITY)
         log('')
         ebitmap = EmulatedBitmap()
@@ -358,7 +352,7 @@ def test_bitmap_sync(bsync_mode, msync_mode='bitmap', failure=None):
         # 1 - Test Backup (w/ Optional induced failure)
         if failure == 'intermediate':
             # Activate blkdebug induced failure for second-to-next read
-            log(vm.hmp_qemu_io(drive0.name, 'flush'))
+            log(vm.hmp_qemu_io(drive0.node, 'flush'))
             log('')
         job = backup(drive0, 1, bsync1, msync_mode,
                      bitmap="bitmap0", bitmap_mode=bsync_mode)
@@ -426,7 +420,7 @@ def test_bitmap_sync(bsync_mode, msync_mode='bitmap', failure=None):
 
         log('--- Cleanup ---\n')
         vm.qmp_log("block-dirty-bitmap-remove",
-                   node=drive0.name, name="bitmap0")
+                   node=drive0.node, name="bitmap0")
         bitmaps = vm.query_bitmaps()
         log({'bitmaps': bitmaps}, indent=2)
         vm.shutdown()
@@ -467,22 +461,21 @@ def test_backup_api():
             'filename': drive0.path
         }
 
+        drive0.node = 'drive0'
         vm.qmp_log('blockdev-add',
                    filters=[iotests.filter_qmp_testfiles],
-                   node_name="drive0",
+                   node_name=drive0.node,
                    driver=drive0.fmt,
                    file=file_config)
-        drive0.node = 'drive0'
-        drive0.device = 'device0'
-        vm.qmp_log("device_add", id=drive0.device,
-                   drive=drive0.name, driver="scsi-hd")
+        vm.qmp_log("device_add", id='device0',
+                   drive=drive0.node, driver="scsi-hd")
         log('')
 
         target0 = Drive(backup_path, vm=vm)
         target0.create_target("backup_target", drive0.fmt, drive0.size)
         log('')
 
-        vm.qmp_log("block-dirty-bitmap-add", node=drive0.name,
+        vm.qmp_log("block-dirty-bitmap-add", node=drive0.node,
                    name="bitmap0", granularity=GRANULARITY)
         log('')
 
@@ -521,7 +514,7 @@ def test_backup_api():
             log("-- Sync mode {:s} tests --\n".format(sync_mode))
             for bitmap in (None, 'bitmap404', 'bitmap0'):
                 for policy in error_cases[sync_mode][bitmap]:
-                    blockdev_backup(drive0.vm, drive0.name, "backup_target",
+                    blockdev_backup(drive0.vm, drive0.node, "backup_target",
                                     sync_mode, job_id='api_job',
                                     bitmap=bitmap, bitmap_mode=policy)
                     log('')