Fix for volume from image snapshot free space issue

create_from_image() function checks for free space in conversion path
(by default /var/lib/cinder/conversion) even if cinder is creating
volume from image snapshot.

If /var/lib/cinder/conversion has less free space than the size of the
image volume is created from, exception will be thrown by
check_available_space() function in image_utils module.

This patch checks if cinder is configured with
allowed_direct_url_schemes = cinder
If so, cinder should not check free space in conversion path because
volume is created from image snapshot.

Closes-Bug: #1683228
Change-Id: I6330ed31dc9336c9d3d09c2d43c8f4913744e9a2

cinder/tests/unit/volume/flows/test_create_volume_flow.py

@@ -1139,6 +1139,71 @@ class CreateVolumeFlowManagerGlanceCinderBackendCase(test.TestCase):
             self.assertFalse(fake_driver.create_cloned_volume.called)
         mock_cleanup_cg.assert_called_once_with(volume)
 
+    @mock.patch('cinder.volume.flows.manager.create_volume.'
+                'CreateVolumeFromSpecTask.'
+                '_cleanup_cg_in_volume')
+    @mock.patch('cinder.image.image_utils.TemporaryImages.fetch')
+    @mock.patch('cinder.volume.flows.manager.create_volume.'
+                'CreateVolumeFromSpecTask.'
+                '_handle_bootable_volume_glance_meta')
+    @mock.patch('cinder.image.image_utils.qemu_img_info')
+    def test_create_from_image_volume_ignore_size(self, mock_qemu_info,
+                                                  handle_bootable,
+                                                  mock_fetch_img,
+                                                  mock_cleanup_cg,
+                                                  format='raw',
+                                                  owner=None,
+                                                  location=True):
+        self.flags(allowed_direct_url_schemes=['cinder'])
+        self.override_config('allowed_direct_url_schemes', 'cinder')
+        mock_fetch_img.return_value = mock.MagicMock(
+            spec=utils.get_file_spec())
+        fake_db = mock.MagicMock()
+        fake_driver = mock.MagicMock()
+        fake_manager = create_volume_manager.CreateVolumeFromSpecTask(
+            mock.MagicMock(), fake_db, fake_driver)
+        fake_image_service = fake_image.FakeImageService()
+
+        volume = fake_volume.fake_volume_obj(self.ctxt,
+                                             host='host@backend#pool')
+        image_volume = fake_volume.fake_volume_obj(self.ctxt,
+                                                   volume_metadata={})
+        image_id = fakes.IMAGE_ID
+        image_info = imageutils.QemuImgInfo()
+        # Making huge image. If cinder will try to convert it, it
+        # will fail because of free space being too low.
+        image_info.virtual_size = '1073741824000000000000'
+        mock_qemu_info.return_value = image_info
+        url = 'cinder://%s' % image_volume['id']
+        image_location = None
+        if location:
+            image_location = (url, [{'url': url, 'metadata': {}}])
+        image_meta = {'id': image_id,
+                      'container_format': 'bare',
+                      'disk_format': format,
+                      'size': 1024,
+                      'owner': owner or self.ctxt.project_id,
+                      'virtual_size': None,
+                      'cinder_encryption_key_id': None}
+
+        fake_driver.clone_image.return_value = (None, False)
+        fake_db.volume_get_all_by_host.return_value = [image_volume]
+        fake_manager._create_from_image(self.ctxt,
+                                        volume,
+                                        image_location,
+                                        image_id,
+                                        image_meta,
+                                        fake_image_service)
+        if format is 'raw' and not owner and location:
+            fake_driver.create_cloned_volume.assert_called_once_with(
+                volume, image_volume)
+            handle_bootable.assert_called_once_with(self.ctxt, volume,
+                                                    image_id=image_id,
+                                                    image_meta=image_meta)
+        else:
+            self.assertFalse(fake_driver.create_cloned_volume.called)
+        mock_cleanup_cg.assert_called_once_with(volume)
+
     def test_create_from_image_volume_in_qcow2_format(self):
         self.test_create_from_image_volume(format='qcow2')
 

cinder/volume/flows/manager/create_volume.py

@@ -823,8 +823,19 @@ class CreateVolumeFromSpecTask(flow_utils.CinderTask):
                 os.path.exists(CONF.image_conversion_dir)):
             os.makedirs(CONF.image_conversion_dir)
         try:
-            image_utils.check_available_space(CONF.image_conversion_dir,
-                                              image_meta['size'], image_id)
+            # cinder should not check free space in conversion directory
+            # if it's creating volume from image snapshot (Bug1683228).
+            # If image disk format is other than raw, cinder should
+            # convert it (this means free space check will be needed).
+            if ('cinder' in CONF.allowed_direct_url_schemes and
+                    image_meta.get('disk_format') == 'raw'):
+                LOG.debug("Creating volume from image snapshot. "
+                          "Skipping free space check on image "
+                          "convert path.")
+            else:
+                image_utils.check_available_space(
+                    CONF.image_conversion_dir,
+                    image_meta['size'], image_id)
         except exception.ImageTooBig as err:
             with excutils.save_and_reraise_exception():
                 self.message.create(