--- a/src/filedata.c	Mon Nov 12 06:03:02 2012 +0000
+++ b/src/filedata.c	Mon Nov 12 18:44:44 2012 +0000
@@ -532,6 +532,7 @@
 {
 	g_assert(fd->magick == FD_MAGICK);
 	g_assert(fd->ref == 0);
+	g_assert(!fd->locked);
 
 	metadata_cache_free(fd);
 	g_hash_table_remove(file_data_pool, fd->original_path);
@@ -630,10 +631,12 @@
 /**
  * \brief Lock the FileData in memory.
  *
- * This allows the caller to prevent a FileData from being freed, even
- * after its refcount is zero.
+ * This allows the caller to prevent a FileData from being freed, even after its refcount is zero.
+ * This is intended to be used in cases where a FileData _should_ stay in memory as an optimization,
+ * even if the code would continue to function properly even if the FileData were freed.  Code that
+ * _requires_ the FileData to remain in memory should continue to use file_data_(un)ref.
  * <p />
- * This differs from file_data_ref in that the behavior is reentrant -- after N calls to
+ * Note: This differs from file_data_ref in that the behavior is reentrant -- after N calls to
  * file_data_lock, a single call to file_data_unlock will unlock the FileData.
  */
 void file_data_lock(FileData *fd)
@@ -666,6 +669,42 @@
 	file_data_consider_free(fd);
 }
 
+/**
+ * \brief Lock all of the FileDatas in the provided list
+ *
+ * \see file_data_lock(FileData)
+ */
+void file_data_lock_list(GList *list)
+{
+	GList *work;
+
+	work = list;
+	while (work)
+		{
+		FileData *fd = work->data;
+		work = work->next;
+		file_data_lock(fd);
+		}
+}
+
+/**
+ * \brief Unlock all of the FileDatas in the provided list
+ *
+ * \see file_data_unlock(FileData)
+ */
+void file_data_unlock_list(GList *list)
+{
+	GList *work;
+
+	work = list;
+	while (work)
+		{
+		FileData *fd = work->data;
+		work = work->next;
+		file_data_unlock(fd);
+		}
+}
+
 /*
  *-----------------------------------------------------------------------------
  * sidecar file info struct

--- a/src/filedata.h	Mon Nov 12 06:03:02 2012 +0000
+++ b/src/filedata.h	Mon Nov 12 18:44:44 2012 +0000
@@ -45,6 +45,8 @@
 
 void file_data_lock(FileData *fd);
 void file_data_unlock(FileData *fd);
+void file_data_lock_list(GList *list);
+void file_data_unlock_list(GList *list);
 
 gboolean file_data_check_changed_files(FileData *fd);
 

--- a/src/view_file_list.c	Mon Nov 12 06:03:02 2012 +0000
+++ b/src/view_file_list.c	Mon Nov 12 18:44:44 2012 +0000
@@ -148,9 +148,25 @@
 	return FALSE;
 }
 
-static void vflist_store_clear(ViewFile *vf)
+static void vflist_store_clear(ViewFile *vf, gboolean unlock_files)
 {
 	GtkTreeModel *store;
+	GList *files = NULL;
+
+	if (unlock_files && vf->marks_enabled)
+		{
+		// unlock locked files in this directory
+		filelist_read(vf->dir_fd, &files, NULL);
+		while (files)
+			{
+			FileData *fd = files->data;
+			files = files->next;
+			file_data_unlock(fd);
+			file_data_unref(fd);  // undo the ref that got added in filelist_read
+			}
+		}
+
+	g_list_free(files);
 	store = gtk_tree_view_get_model(GTK_TREE_VIEW(vf->listview));
 	gtk_tree_model_foreach(store, vflist_store_clear_cb, NULL);
 	gtk_tree_store_clear(GTK_TREE_STORE(store));
@@ -1649,7 +1665,7 @@
 
 	if (!vf->list)
 		{
-		vflist_store_clear(vf);
+		vflist_store_clear(vf, FALSE);
 		vf_send_update(vf);
 		return;
 		}
@@ -1686,6 +1702,20 @@
 		file_data_unregister_notify_func(vf_notify_cb, vf); /* we don't need the notification of changes detected by filelist_read */
 
 		ret = filelist_read(vf->dir_fd, &vf->list, NULL);
+
+		if (vf->marks_enabled)
+		        {
+		        // When marks are enabled, lock FileDatas so that we don't end up re-parsing XML
+		        // each time a mark is changed.
+		        file_data_lock_list(vf->list);
+		        }
+	        else
+			{
+			// FIXME: only do this when needed (aka when we just switched from
+			// FIXME: marks-enabled to marks-disabled)
+			file_data_unlock_list(vf->list);
+			}
+
 		vf->list = file_data_filter_marks_list(vf->list, vf_marks_get_filter(vf));
 		file_data_register_notify_func(vf_notify_cb, vf, NOTIFY_PRIORITY_MEDIUM);
 
@@ -1697,6 +1727,8 @@
 
 	vflist_populate_view(vf, FALSE);
 
+	DEBUG_1("%s vflist_refresh: free filelist", get_exec_time());
+
 	filelist_free(old_list);
 	DEBUG_1("%s vflist_refresh: done", get_exec_time());
 
@@ -1868,7 +1900,7 @@
 	vf->dir_fd = file_data_ref(dir_fd);
 
 	/* force complete reload */
-	vflist_store_clear(vf);
+	vflist_store_clear(vf, TRUE);
 
 	filelist_free(vf->list);
 	vf->list = NULL;
@@ -1995,6 +2027,16 @@
 			gtk_tree_view_column_set_visible(column, enable);
 		}
 
+	if (enable)
+		{
+		// Previously disabled, which means that vf->list is complete
+		file_data_lock_list(vf->list);
+		}
+	else
+		{
+		// Previously enabled, which means that vf->list is incomplete
+		}
+
 	g_list_free(columns);
 }