#define FL_CLOSE 64 /* unlock on close */
#define FL_SLEEP 128 /* A blocking lock */
+/*
+ * Special return value from posix_lock_file() and vfs_lock_file() for
+ * asynchronous locking.
+ */
+#define FILE_LOCK_DEFERRED 1
+
/*
* The POSIX file lock owner is determined by
* the "struct files_struct" in the thread group