v4.19.13 snapshot.
diff --git a/arch/ia64/include/asm/cacheflush.h b/arch/ia64/include/asm/cacheflush.h
new file mode 100644
index 0000000..6d3478f
--- /dev/null
+++ b/arch/ia64/include/asm/cacheflush.h
@@ -0,0 +1,55 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_IA64_CACHEFLUSH_H
+#define _ASM_IA64_CACHEFLUSH_H
+
+/*
+ * Copyright (C) 2002 Hewlett-Packard Co
+ *	David Mosberger-Tang <davidm@hpl.hp.com>
+ */
+
+#include <linux/page-flags.h>
+#include <linux/bitops.h>
+
+#include <asm/page.h>
+
+/*
+ * Cache flushing routines.  This is the kind of stuff that can be very expensive, so try
+ * to avoid them whenever possible.
+ */
+
+#define flush_cache_all()			do { } while (0)
+#define flush_cache_mm(mm)			do { } while (0)
+#define flush_cache_dup_mm(mm)			do { } while (0)
+#define flush_cache_range(vma, start, end)	do { } while (0)
+#define flush_cache_page(vma, vmaddr, pfn)	do { } while (0)
+#define flush_icache_page(vma,page)		do { } while (0)
+#define flush_cache_vmap(start, end)		do { } while (0)
+#define flush_cache_vunmap(start, end)		do { } while (0)
+
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
+#define flush_dcache_page(page)			\
+do {						\
+	clear_bit(PG_arch_1, &(page)->flags);	\
+} while (0)
+
+#define flush_dcache_mmap_lock(mapping)		do { } while (0)
+#define flush_dcache_mmap_unlock(mapping)	do { } while (0)
+
+extern void flush_icache_range (unsigned long start, unsigned long end);
+extern void clflush_cache_range(void *addr, int size);
+
+
+#define flush_icache_user_range(vma, page, user_addr, len)					\
+do {												\
+	unsigned long _addr = (unsigned long) page_address(page) + ((user_addr) & ~PAGE_MASK);	\
+	flush_icache_range(_addr, _addr + (len));						\
+} while (0)
+
+#define copy_to_user_page(vma, page, vaddr, dst, src, len) \
+do { memcpy(dst, src, len); \
+     flush_icache_user_range(vma, page, vaddr, len); \
+} while (0)
+#define copy_from_user_page(vma, page, vaddr, dst, src, len) \
+	memcpy(dst, src, len)
+
+#endif /* _ASM_IA64_CACHEFLUSH_H */