v4.19.13 snapshot.
diff --git a/arch/ia64/include/asm/cache.h b/arch/ia64/include/asm/cache.h
new file mode 100644
index 0000000..4eb6f74
--- /dev/null
+++ b/arch/ia64/include/asm/cache.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_IA64_CACHE_H
+#define _ASM_IA64_CACHE_H
+
+
+/*
+ * Copyright (C) 1998-2000 Hewlett-Packard Co
+ * David Mosberger-Tang <davidm@hpl.hp.com>
+ */
+
+/* Bytes per L1 (data) cache line. */
+#define L1_CACHE_SHIFT CONFIG_IA64_L1_CACHE_SHIFT
+#define L1_CACHE_BYTES (1 << L1_CACHE_SHIFT)
+
+#ifdef CONFIG_SMP
+# define SMP_CACHE_SHIFT L1_CACHE_SHIFT
+# define SMP_CACHE_BYTES L1_CACHE_BYTES
+#else
+ /*
+ * The "aligned" directive can only _increase_ alignment, so this is
+ * safe and provides an easy way to avoid wasting space on a
+ * uni-processor:
+ */
+# define SMP_CACHE_SHIFT 3
+# define SMP_CACHE_BYTES (1 << 3)
+#endif
+
+#define __read_mostly __attribute__((__section__(".data..read_mostly")))
+
+#endif /* _ASM_IA64_CACHE_H */