1 files changed, 69 insertions, 0 deletions
diff --git a/arch/s390/include/asm/archrandom.h b/arch/s390/include/asm/archrandom.h
new file mode 100644
index 000000000000..6033901a40b2
--- /dev/null
+++ b/arch/s390/include/asm/archrandom.h
@@ -0,0 +1,69 @@
+/*
+ * Kernel interface for the s390 arch_random_* functions
+ *
+ * Copyright IBM Corp. 2017
+ *
+ * Author: Harald Freudenberger <freude@de.ibm.com>
+ *
+ */
+
+#ifndef _ASM_S390_ARCHRANDOM_H
+#define _ASM_S390_ARCHRANDOM_H
+
+#ifdef CONFIG_ARCH_RANDOM
+
+#include <linux/static_key.h>
+#include <linux/atomic.h>
+#include <asm/cpacf.h>
+
+DECLARE_STATIC_KEY_FALSE(s390_arch_random_available);
+extern atomic64_t s390_arch_random_counter;
+
+static void s390_arch_random_generate(u8 *buf, unsigned int nbytes)
+{
+	cpacf_trng(NULL, 0, buf, nbytes);
+	atomic64_add(nbytes, &s390_arch_random_counter);
+}
+
+static inline bool arch_has_random(void)
+{
+	if (static_branch_likely(&s390_arch_random_available))
+		return true;
+	return false;
+}
+
+static inline bool arch_has_random_seed(void)
+{
+	return arch_has_random();
+}
+
+static inline bool arch_get_random_long(unsigned long *v)
+{
+	if (static_branch_likely(&s390_arch_random_available)) {
+		s390_arch_random_generate((u8 *)v, sizeof(*v));
+		return true;
+	}
+	return false;
+}
+
+static inline bool arch_get_random_int(unsigned int *v)
+{
+	if (static_branch_likely(&s390_arch_random_available)) {
+		s390_arch_random_generate((u8 *)v, sizeof(*v));
+		return true;
+	}
+	return false;
+}
+
+static inline bool arch_get_random_seed_long(unsigned long *v)
+{
+	return arch_get_random_long(v);
+}
+
+static inline bool arch_get_random_seed_int(unsigned int *v)
+{
+	return arch_get_random_int(v);
+}
+
+#endif /* CONFIG_ARCH_RANDOM */
+#endif /* _ASM_S390_ARCHRANDOM_H */