+/*****************************************************************************/
+/*
+ * key reference with possession attribute handling
+ *
+ * NOTE! key_ref_t is a typedef'd pointer to a type that is not actually
+ * defined. This is because we abuse the bottom bit of the reference to carry a
+ * flag to indicate whether the calling process possesses that key in one of
+ * its keyrings.
+ *
+ * the key_ref_t has been made a separate type so that the compiler can reject
+ * attempts to dereference it without proper conversion.
+ *
+ * the three functions are used to assemble and disassemble references
+ */
+typedef struct __key_reference_with_attributes *key_ref_t;
+
+static inline key_ref_t make_key_ref(const struct key *key,
+ unsigned long possession)
+{
+ return (key_ref_t) ((unsigned long) key | possession);
+}
+
+static inline struct key *key_ref_to_ptr(const key_ref_t key_ref)
+{
+ return (struct key *) ((unsigned long) key_ref & ~1UL);
+}
+
+static inline unsigned long is_key_possessed(const key_ref_t key_ref)
+{
+ return (unsigned long) key_ref & 1UL;
+}
+