diff --git a/core/modules/file/file.module b/core/modules/file/file.module
index 96c5d08..1e6a963 100644
--- a/core/modules/file/file.module
+++ b/core/modules/file/file.module
@@ -660,8 +660,9 @@ function file_cron() {
       ->range(0, 100)
       ->execute();
     $files = File::loadMultiple($fids);
+    $file_usage = \Drupal::service('file.usage');
     foreach ($files as $file) {
-      $references = \Drupal::service('file.usage')->listUsage($file);
+      $references = $file_usage->listUsage($file);
       if (empty($references)) {
         if (file_exists($file->getFileUri())) {
           $file->delete();
@@ -1285,7 +1286,10 @@ function file_managed_file_value(&$element, $input, FormStateInterface $form_sta
 
       // Load files if the FIDs have changed to confirm they exist.
       if (!empty($input['fids'])) {
-        $fids = array_keys(File::loadMultiple($input['fids']));
+        $fids = \Drupal::entityQuery('file')
+          ->condition('fid', $input['fids'], 'IN')
+          ->exists('fid')
+          ->execute();
       }
     }
   }
@@ -1303,7 +1307,10 @@ function file_managed_file_value(&$element, $input, FormStateInterface $form_sta
 
     // Confirm that the file exists when used as a default value.
     if (!empty($default_fids)) {
-      $fids = array_keys(File::loadMultiple($default_fids));
+      $fids = \Drupal::entityQuery('file')
+        ->condition('fid', $default_fids, 'IN')
+        ->exists('fid')
+        ->execute();
     }
   }
 
@@ -1324,10 +1331,11 @@ function file_managed_file_validate(&$element, FormStateInterface $form_state) {
   $clicked_button = end($form_state['triggering_element']['#parents']);
   if ($clicked_button != 'remove_button' && !empty($element['fids']['#value'])) {
     $files = File::loadMultiple($element['fids']['#value']);
+    $file_usage = \Drupal::service('file.usage');
     foreach ($element['fids']['#value'] as $fid) {
       if (!empty($files[$fid])) {
         if ($files[$fid]->isPermanent()) {
-          $references = \Drupal::service('file.usage')->listUsage($files[$fid]);
+          $references = $file_usage->listUsage($files[$fid]);
           if (empty($references)) {
             form_error($element, $form_state, t('The file used in the !name field may not be referenced.', array('!name' => $element['#title'])));
           }
@@ -1538,7 +1546,7 @@ function template_preprocess_file_link(&$variables) {
   $icon_directory = $variables['icon_directory'];
 
   $url = file_create_url($file->getFileUri());
-  $file_entity = ($file instanceof File) ? $file : File::load($file->fid);
+  $file_entity = ($file instanceof FileInterface) ? $file : File::load($file->fid);
 
   // Human-readable names, for use as text-alternatives to icons.
   $mime_name = array(
diff --git a/core/modules/file/src/Tests/CopyTest.php b/core/modules/file/src/Tests/CopyTest.php
index 862ab57..aec77dd 100644
--- a/core/modules/file/src/Tests/CopyTest.php
+++ b/core/modules/file/src/Tests/CopyTest.php
@@ -42,9 +42,6 @@ function testNormal() {
     // Reload the file from the database and check that the changes were
     // actually saved.
     $fid = $result->id();
-    $file_storage = $this->container->get('entity.manager')->getStorage('file');
-    $file_storage->resetCache(array($fid));
-
     $this->assertFileUnchanged($result, File::load($fid));
   }
 
@@ -72,12 +69,8 @@ function testExistingRename() {
 
     // Load all the affected files to check the changes that actually made it
     // to the database.
-    $file_storage = $this->container->get('entity.manager')->getStorage('file');
-    $file_storage->resetCache(array($source->id()));
     $loaded_source = File::load($source->id());
-    $file_storage->resetCache(array($target->id()));
     $loaded_target = File::load($target->id());
-    $file_storage->resetCache(array($result->id()));
     $loaded_result = File::load($result->id());
 
     // Verify that the source file wasn't changed.
@@ -116,12 +109,8 @@ function testExistingReplace() {
 
     // Load all the affected files to check the changes that actually made it
     // to the database.
-    $file_storage = $this->container->get('entity.manager')->getStorage('file');
-    $file_storage->resetCache(array($source->id()));
     $loaded_source = File::load($source->id());
-    $file_storage->resetCache(array($target->id()));
     $loaded_target = File::load($target->id());
-    $file_storage->resetCache(array($result->id()));
     $loaded_result = File::load($result->id());
 
     // Verify that the source file wasn't changed.
@@ -155,11 +144,7 @@ function testExistingError() {
     // Check that the correct hooks were called.
     $this->assertFileHooksCalled(array());
 
-    $file_storage = $this->container->get('entity.manager')->getStorage('file');
-
-    $file_storage->resetCache(array($source->id()));
     $this->assertFileUnchanged($source, File::load($source->id()));
-    $file_storage->resetCache(array($target->id()));
     $this->assertFileUnchanged($target, File::load($target->id()));
   }
 }