5 files changed, 73 insertions, 1 deletions

diff --git a/arch/s390/kvm/Makefile b/arch/s390/kvm/Makefile
index f3bf11a88bc7..e5221ec0b8e3 100644
--- a/arch/s390/kvm/Makefile
+++ b/arch/s390/kvm/Makefile
@@ -10,5 +10,5 @@ common-objs = $(addprefix ../../../virt/kvm/, kvm_main.o)
 
 EXTRA_CFLAGS += -Ivirt/kvm -Iarch/s390/kvm
 
-kvm-objs := $(common-objs) kvm-s390.o sie64a.o intercept.o interrupt.o priv.o sigp.o
+kvm-objs := $(common-objs) kvm-s390.o sie64a.o intercept.o interrupt.o priv.o sigp.o diag.o
 obj-$(CONFIG_KVM) += kvm.o
diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c
new file mode 100644
index 000000000000..f639a152869f
--- /dev/null
+++ b/arch/s390/kvm/diag.c
@@ -0,0 +1,67 @@
+/*
+ * diag.c - handling diagnose instructions
+ *
+ * Copyright IBM Corp. 2008
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ *
+ *    Author(s): Carsten Otte <cotte@de.ibm.com>
+ *               Christian Borntraeger <borntraeger@de.ibm.com>
+ */
+
+#include <linux/kvm.h>
+#include <linux/kvm_host.h>
+#include "kvm-s390.h"
+
+static int __diag_time_slice_end(struct kvm_vcpu *vcpu)
+{
+        VCPU_EVENT(vcpu, 5, "%s", "diag time slice end");
+        vcpu->stat.diagnose_44++;
+        vcpu_put(vcpu);
+        schedule();
+        vcpu_load(vcpu);
+        return 0;
+}
+
+static int __diag_ipl_functions(struct kvm_vcpu *vcpu)
+{
+        unsigned int reg = vcpu->arch.sie_block->ipa & 0xf;
+        unsigned long subcode = vcpu->arch.guest_gprs[reg] & 0xffff;
+
+        VCPU_EVENT(vcpu, 5, "diag ipl functions, subcode %lx", subcode);
+        switch (subcode) {
+        case 3:
+                vcpu->run->s390_reset_flags = KVM_S390_RESET_CLEAR;
+                break;
+        case 4:
+                vcpu->run->s390_reset_flags = 0;
+                break;
+        default:
+                return -ENOTSUPP;
+        }
+
+        atomic_clear_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
+        vcpu->run->s390_reset_flags |= KVM_S390_RESET_SUBSYSTEM;
+        vcpu->run->s390_reset_flags |= KVM_S390_RESET_IPL;
+        vcpu->run->s390_reset_flags |= KVM_S390_RESET_CPU_INIT;
+        vcpu->run->exit_reason = KVM_EXIT_S390_RESET;
+        VCPU_EVENT(vcpu, 3, "requesting userspace resets %lx",
+          vcpu->run->s390_reset_flags);
+        return -EREMOTE;
+}
+
+int kvm_s390_handle_diag(struct kvm_vcpu *vcpu)
+{
+        int code = (vcpu->arch.sie_block->ipb & 0xfff0000) >> 16;
+
+        switch (code) {
+        case 0x44:
+                return __diag_time_slice_end(vcpu);
+        case 0x308:
+                return __diag_ipl_functions(vcpu);
+        default:
+                return -ENOTSUPP;
+        }
+}
diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c
index 9f0d8b239436..349581a26103 100644
--- a/arch/s390/kvm/intercept.c
+++ b/arch/s390/kvm/intercept.c
@@ -95,6 +95,7 @@ static int handle_lctl(struct kvm_vcpu *vcpu)
 }
 
 static intercept_handler_t instruction_handlers[256] = {
+        [0x83] = kvm_s390_handle_diag,
         [0xae] = kvm_s390_handle_sigp,
         [0xb2] = kvm_s390_handle_priv,
         [0xb7] = handle_lctl,
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index c632180739ee..d3b1de83678b 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -63,6 +63,7 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
         { "instruction_sigp_set_arch", VCPU_STAT(instruction_sigp_arch) },
         { "instruction_sigp_set_prefix", VCPU_STAT(instruction_sigp_prefix) },
         { "instruction_sigp_restart", VCPU_STAT(instruction_sigp_restart) },
+        { "diagnose_44", VCPU_STAT(diagnose_44) },
         { NULL }
 };
 
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index e6e5756a0e07..3893cf12eacf 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -58,4 +58,7 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu);
 /* implemented in kvm-s390.c */
 int __kvm_s390_vcpu_store_status(struct kvm_vcpu *vcpu,
                                  unsigned long addr);
+/* implemented in diag.c */
+int kvm_s390_handle_diag(struct kvm_vcpu *vcpu);
+
 #endif