diff --git a/stepmania/src/RageFileDriver.cpp b/stepmania/src/RageFileDriver.cpp
index 165523f076..0883acc66a 100644
--- a/stepmania/src/RageFileDriver.cpp
+++ b/stepmania/src/RageFileDriver.cpp
@@ -65,7 +65,7 @@ int RageFileObj::GetFileSize()
 	return ret;
 }
 
-int RageFileDriver::GetPathValue( CString path )
+int RageFileDriver::GetPathValue( const CString &path )
 {
 	vector<CString> parts;
 	split( path, SLASH, parts, true );
@@ -99,23 +99,23 @@ int RageFileDriver::GetPathValue( CString path )
 	return 0;
 }
 
-void RageFileDriver::GetDirListing( CString sPath, CStringArray &AddTo, bool bOnlyDirs, bool bReturnPathToo )
+void RageFileDriver::GetDirListing( const CString &sPath, CStringArray &AddTo, bool bOnlyDirs, bool bReturnPathToo )
 {
 	FDB->GetDirListing( sPath, AddTo, bOnlyDirs, bReturnPathToo );
 }
 
-RageFileManager::FileType RageFileDriver::GetFileType( CString sPath )
+RageFileManager::FileType RageFileDriver::GetFileType( const CString &sPath )
 {
 	/* XXX */
 	return (RageFileManager::FileType) FDB->GetFileType( sPath );
 }
 
-int RageFileDriver::GetFileSizeInBytes( CString sPath )
+int RageFileDriver::GetFileSizeInBytes( const CString &sPath )
 {
 	return FDB->GetFileSize( sPath );
 }
 
-int RageFileDriver::GetFileModTime( CString sPath )
+int RageFileDriver::GetFileModTime( const CString &sPath )
 {
 	return FDB->GetFileModTime( sPath );
 }
diff --git a/stepmania/src/RageFileDriver.h b/stepmania/src/RageFileDriver.h
index b28acf79ac..f5b4dd631a 100644
--- a/stepmania/src/RageFileDriver.h
+++ b/stepmania/src/RageFileDriver.h
@@ -11,12 +11,12 @@ class RageFileDriver
 public:
 	RageFileDriver( FilenameDB *db ) { FDB = db; }
 	virtual ~RageFileDriver();
-	virtual RageFileObj *Open( CString path, RageFile::OpenMode mode, RageFile &p, int &err ) = 0;
-	virtual void GetDirListing( CString sPath, CStringArray &AddTo, bool bOnlyDirs, bool bReturnPathToo );
-	virtual RageFileManager::FileType GetFileType( CString sPath );
-	virtual int GetFileSizeInBytes( CString sFilePath );
-	virtual int GetFileModTime( CString sPath );
-	virtual int GetPathValue( CString path );
+	virtual RageFileObj *Open( const CString &path, RageFile::OpenMode mode, RageFile &p, int &err ) = 0;
+	virtual void GetDirListing( const CString &sPath, CStringArray &AddTo, bool bOnlyDirs, bool bReturnPathToo );
+	virtual RageFileManager::FileType GetFileType( const CString &sPath );
+	virtual int GetFileSizeInBytes( const CString &sFilePath );
+	virtual int GetFileModTime( const CString &sPath );
+	virtual int GetPathValue( const CString &path );
 	virtual bool Ready() { return true; } /* see RageFileManager::MountpointIsReady */
 	virtual void FlushDirCache( const CString &sPath );
 
diff --git a/stepmania/src/RageFileDriverDirect.cpp b/stepmania/src/RageFileDriverDirect.cpp
index 52d81c9b89..1422d88425 100644
--- a/stepmania/src/RageFileDriverDirect.cpp
+++ b/stepmania/src/RageFileDriverDirect.cpp
@@ -192,9 +192,10 @@ static bool CreateDirectories( CString Path )
 	return true;
 }
 
-RageFileObj *RageFileDriverDirect::Open( CString sPath, RageFile::OpenMode mode, RageFile &p, int &err )
+RageFileObj *RageFileDriverDirect::Open( const CString &path, RageFile::OpenMode mode, RageFile &p, int &err )
 {
-	sPath = root + sPath;
+	CString sPath = root + path;
+
 	/* XXX: make sure this will partially resolve.  eg. if "abc/def" exists,
 	 * and we're opening "ABC/DEF/GHI/jkl/mno", make sure this will resolve
 	 * to "abc/def/GHI/jkl/mno"; we'll create the missing ones later. */
diff --git a/stepmania/src/RageFileDriverDirect.h b/stepmania/src/RageFileDriverDirect.h
index e51e5c48b3..8e97de9b0e 100644
--- a/stepmania/src/RageFileDriverDirect.h
+++ b/stepmania/src/RageFileDriverDirect.h
@@ -8,7 +8,7 @@ class RageFileDriverDirect: public RageFileDriver
 public:
 	RageFileDriverDirect( CString root );
 
-	RageFileObj *Open( CString path, RageFile::OpenMode mode, RageFile &p, int &err );
+	RageFileObj *Open( const CString &path, RageFile::OpenMode mode, RageFile &p, int &err );
 	bool Ready();
 
 private: