[PATCH v4 01/15] s390: zcrypt: externalize AP instructions available function

[Tony Krowiak]

If the AP instructions are not available on the linux host, then
AP devices can not be interpreted by the SIE. The AP bus has a
function it uses to determine if the AP instructions are
available. This patch provides a new function that wraps the
AP bus's function to externalize it for use by KVM.

Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Pierre Morel <pmorel@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Harald Freudenberger <freude@xxxxxxxxxxxxxxxxxx>
---
 arch/s390/include/asm/ap.h     |    7 +++++++
 arch/s390/include/asm/kvm-ap.h |   23 +++++++++++++++++++++++
 arch/s390/kvm/Makefile         |    2 +-
 arch/s390/kvm/kvm-ap.c         |   21 +++++++++++++++++++++
 drivers/s390/crypto/ap_bus.c   |    6 ++++++
 5 files changed, 58 insertions(+), 1 deletions(-)
 create mode 100644 arch/s390/include/asm/kvm-ap.h
 create mode 100644 arch/s390/kvm/kvm-ap.c

diff --git a/arch/s390/include/asm/ap.h b/arch/s390/include/asm/ap.h
index c1bedb4..7773bfd 100644
--- a/arch/s390/include/asm/ap.h
+++ b/arch/s390/include/asm/ap.h
@@ -120,4 +120,11 @@ struct ap_queue_status ap_queue_irq_ctrl(ap_qid_t qid,
 					 struct ap_qirq_ctrl qirqctrl,
 					 void *ind);
 
+/**
+ * ap_instructions_installed() - Tests whether AP instructions are installed
+ *
+ * Returns 1 if the AP instructions are installed, otherwise; returns 0
+ */
+int ap_instructions_installed(void);
+
 #endif /* _ASM_S390_AP_H_ */
diff --git a/arch/s390/include/asm/kvm-ap.h b/arch/s390/include/asm/kvm-ap.h
new file mode 100644
index 0000000..84412a9
--- /dev/null
+++ b/arch/s390/include/asm/kvm-ap.h
@@ -0,0 +1,23 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Adjunct Processor (AP) configuration management for KVM guests
+ *
+ * Copyright IBM Corp. 2018
+ *
+ * Author(s): Tony Krowiak <akrowia@xxxxxxxxxxxxxxxxxx>
+ */
+
+#ifndef _ASM_KVM_AP
+#define _ASM_KVM_AP
+
+/**
+ * kvm_ap_instructions_installed()
+ *
+ * Tests whether AP instructions are installed on the linux host
+ *
+ * Returns 1 if the AP instructions are installed on the host, otherwise;
+ * returns 0
+ */
+int kvm_ap_instructions_installed(void);
+
+#endif /* _ASM_KVM_AP */
diff --git a/arch/s390/kvm/Makefile b/arch/s390/kvm/Makefile
index 05ee90a..1876bfe 100644
--- a/arch/s390/kvm/Makefile
+++ b/arch/s390/kvm/Makefile
@@ -9,6 +9,6 @@ common-objs = $(KVM)/kvm_main.o $(KVM)/eventfd.o  $(KVM)/async_pf.o $(KVM)/irqch
 ccflags-y := -Ivirt/kvm -Iarch/s390/kvm
 
 kvm-objs := $(common-objs) kvm-s390.o intercept.o interrupt.o priv.o sigp.o
-kvm-objs += diag.o gaccess.o guestdbg.o vsie.o
+kvm-objs += diag.o gaccess.o guestdbg.o vsie.o kvm-ap.o
 
 obj-$(CONFIG_KVM) += kvm.o
diff --git a/arch/s390/kvm/kvm-ap.c b/arch/s390/kvm/kvm-ap.c
new file mode 100644
index 0000000..1267588
--- /dev/null
+++ b/arch/s390/kvm/kvm-ap.c
@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Adjunct Processor (AP) configuration management for KVM guests
+ *
+ * Copyright IBM Corp. 2018
+ *
+ * Author(s): Tony Krowiak <akrowia@xxxxxxxxxxxxxxxxxx>
+ */
+#include <linux/kernel.h>
+#include <asm/kvm-ap.h>
+#include <asm/ap.h>
+
+int kvm_ap_instructions_installed(void)
+{
+#ifdef CONFIG_ZCRYPT
+	return ap_instructions_installed();
+#else
+	return 0;
+#endif
+}
+EXPORT_SYMBOL(kvm_ap_instructions_installed);
diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c
index 35a0c2b..9d108b6 100644
--- a/drivers/s390/crypto/ap_bus.c
+++ b/drivers/s390/crypto/ap_bus.c
@@ -210,6 +210,12 @@ int ap_query_configuration(struct ap_config_info *info)
 }
 EXPORT_SYMBOL(ap_query_configuration);
 
+int ap_instructions_installed(void)
+{
+	return (ap_instructions_available() == 0);
+}
+EXPORT_SYMBOL(ap_instructions_installed);
+
 /**
  * ap_init_configuration(): Allocate and query configuration array.
  */
-- 
1.7.1