#define ORANGEFS_VFS_OP_FSYNC 0xFF00EE01
#define ORANGEFS_VFS_OP_FSKEY 0xFF00EE02
#define ORANGEFS_VFS_OP_READDIRPLUS 0xFF00EE03
+#define ORANGEFS_VFS_OP_FEATURES 0xFF00EE05 /* 2.9.6 */
+
+/* features is a 64-bit unsigned bitmask */
+#define ORANGEFS_FEATURE_READAHEAD 1
/*
* Misc constants. Please retain them as multiples of 8!