diff --git a/src/fs/reiser4.cpp b/src/fs/reiser4.cpp
index 1229dd0..7f70b1c 100644
--- a/src/fs/reiser4.cpp
+++ b/src/fs/reiser4.cpp
@@ -19,6 +19,7 @@
 
 #include "fs/reiser4.h"
 
+#include "util/capacity.h"
 #include "util/externalcommand.h"
 
 #include <QStringList>
@@ -49,6 +50,13 @@ namespace FS
 		m_Backup = cmdSupportCore;
 	}
 
+	qint64 reiser4::maxCapacity() const
+	{
+		// looks like it's actually unknown. see
+		// http://en.wikipedia.org/wiki/Comparison_of_file_systems
+		return Capacity::unitFactor(Capacity::Byte, Capacity::EiB);
+	}
+
 	qint64 reiser4::readUsedCapacity(const QString& deviceNode) const
 	{
 		ExternalCommand cmd("debugfs.reiser4", QStringList() << deviceNode);
diff --git a/src/fs/reiser4.h b/src/fs/reiser4.h
index 13a1c3c..3b4df49 100644
--- a/src/fs/reiser4.h
+++ b/src/fs/reiser4.h
@@ -56,6 +56,8 @@ namespace FS
 			virtual CommandSupportType supportCopy() const { return m_Copy; }
 			virtual CommandSupportType supportBackup() const { return m_Backup; }
 
+			virtual qint64 maxCapacity() const;
+
 		public:
 			static CommandSupportType m_GetUsed;
 			static CommandSupportType m_GetLabel;