Index: uspace/lib/ext4/src/ops.c
===================================================================
--- uspace/lib/ext4/src/ops.c	(revision 4fcc2dee0dd39ba010093d693f0dfaa897db6f69)
+++ uspace/lib/ext4/src/ops.c	(revision f78308153763110781d49aaa03881ea1bc9d48fb)
@@ -810,15 +810,14 @@
 }
 
-/** Extract device identifier from node.
+/** Get service ID for a service-special file.
  *
  * @param node Node to extract id from
  *
- * @return id of device, where is the filesystem
+ * @return Service ID for a service-special file, zero for a regular file.
  *
  */
 service_id_t ext4_service_get(fs_node_t *fn)
 {
-	ext4_node_t *enode = EXT4_NODE(fn);
-	return enode->instance->service_id;
+	return 0;
 }
 
Index: uspace/srv/fs/fat/fat_ops.c
===================================================================
--- uspace/srv/fs/fat/fat_ops.c	(revision 4fcc2dee0dd39ba010093d693f0dfaa897db6f69)
+++ uspace/srv/fs/fat/fat_ops.c	(revision f78308153763110781d49aaa03881ea1bc9d48fb)
@@ -839,5 +839,5 @@
 service_id_t fat_service_get(fs_node_t *fn)
 {
-	return FAT_NODE(fn)->idx->service_id;
+	return 0;
 }
 
Index: uspace/srv/fs/mfs/mfs_ops.c
===================================================================
--- uspace/srv/fs/mfs/mfs_ops.c	(revision 4fcc2dee0dd39ba010093d693f0dfaa897db6f69)
+++ uspace/srv/fs/mfs/mfs_ops.c	(revision f78308153763110781d49aaa03881ea1bc9d48fb)
@@ -392,6 +392,5 @@
 mfs_service_get(fs_node_t *fsnode)
 {
-	struct mfs_node *node = fsnode->data;
-	return node->instance->service_id;
+	return 0;
 }
 
Index: uspace/srv/fs/udf/udf_ops.c
===================================================================
--- uspace/srv/fs/udf/udf_ops.c	(revision 4fcc2dee0dd39ba010093d693f0dfaa897db6f69)
+++ uspace/srv/fs/udf/udf_ops.c	(revision f78308153763110781d49aaa03881ea1bc9d48fb)
@@ -104,8 +104,4 @@
 static service_id_t udf_service_get(fs_node_t *node)
 {
-	udf_node_t *udfn = UDF_NODE(node);
-	if (udfn)
-		return udfn->instance->service_id;
-
 	return 0;
 }