1 files changed, 82 insertions, 0 deletions
diff --git a/arch/s390/include/asm/barrier.h b/arch/s390/include/asm/barrier.h
new file mode 100644
index 000000000..82de2a7c4
--- /dev/null
+++ b/arch/s390/include/asm/barrier.h
@@ -0,0 +1,82 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright IBM Corp. 1999, 2009
+ *
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ */
+
+#ifndef __ASM_BARRIER_H
+#define __ASM_BARRIER_H
+
+/*
+ * Force strict CPU ordering.
+ * And yes, this is required on UP too when we're talking
+ * to devices.
+ */
+
+#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
+/* Fast-BCR without checkpoint synchronization */
+#define __ASM_BCR_SERIALIZE "bcr 14,0\n"
+#else
+#define __ASM_BCR_SERIALIZE "bcr 15,0\n"
+#endif
+
+static __always_inline void bcr_serialize(void)
+{
+	asm volatile(__ASM_BCR_SERIALIZE : : : "memory");
+}
+
+#define __mb()		bcr_serialize()
+#define __rmb()		barrier()
+#define __wmb()		barrier()
+#define __dma_rmb()	__mb()
+#define __dma_wmb()	__mb()
+#define __smp_mb()	__mb()
+#define __smp_rmb()	__rmb()
+#define __smp_wmb()	__wmb()
+
+#define __smp_store_release(p, v)					\
+do {									\
+	compiletime_assert_atomic_type(*p);				\
+	barrier();							\
+	WRITE_ONCE(*p, v);						\
+} while (0)
+
+#define __smp_load_acquire(p)						\
+({									\
+	typeof(*p) ___p1 = READ_ONCE(*p);				\
+	compiletime_assert_atomic_type(*p);				\
+	barrier();							\
+	___p1;								\
+})
+
+#define __smp_mb__before_atomic()	barrier()
+#define __smp_mb__after_atomic()	barrier()
+
+/**
+ * array_index_mask_nospec - generate a mask for array_idx() that is
+ * ~0UL when the bounds check succeeds and 0 otherwise
+ * @index: array element index
+ * @size: number of elements in array
+ */
+#define array_index_mask_nospec array_index_mask_nospec
+static inline unsigned long array_index_mask_nospec(unsigned long index,
+						    unsigned long size)
+{
+	unsigned long mask;
+
+	if (__builtin_constant_p(size) && size > 0) {
+		asm("	clgr	%2,%1\n"
+		    "	slbgr	%0,%0\n"
+		    :"=d" (mask) : "d" (size-1), "d" (index) :"cc");
+		return mask;
+	}
+	asm("	clgr	%1,%2\n"
+	    "	slbgr	%0,%0\n"
+	    :"=d" (mask) : "d" (size), "d" (index) :"cc");
+	return ~mask;
+}
+
+#include <asm-generic/barrier.h>
+
+#endif /* __ASM_BARRIER_H */