KVM: s390: arch backend for the kvm kernel module

This patch contains the port of Qumranet's kvm kernel module to IBM zSeries
 (aka s390x, mainframe) architecture. It uses the mainframe's virtualization
instruction SIE to run virtual machines with up to 64 virtual CPUs each.
This port is only usable on 64bit host kernels, and can only run 64bit guest
kernels. However, running 31bit applications in guest userspace is possible.

The following source files are introduced by this patch
arch/s390/kvm/kvm-s390.c    similar to arch/x86/kvm/x86.c, this implements all
                            arch callbacks for kvm. __vcpu_run calls back into
                            sie64a to enter the guest machine context
arch/s390/kvm/sie64a.S      assembler function sie64a, which enters guest
                            context via SIE, and switches world before and after                            that
include/asm-s390/kvm_host.h contains all vital data structures needed to run
                            virtual machines on the mainframe
include/asm-s390/kvm.h      defines kvm_regs and friends for user access to
                            guest register content
arch/s390/kvm/gaccess.h     functions similar to uaccess to access guest memory
arch/s390/kvm/kvm-s390.h    header file for kvm-s390 internals, extended by
                            later patches

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 40 insertions, 1 deletions

diff --git a/include/asm-s390/kvm.h b/include/asm-s390/kvm.h
index 573f2a351386..d74002f95794 100644
--- a/include/asm-s390/kvm.h
+++ b/include/asm-s390/kvm.h
@@ -1,6 +1,45 @@
 #ifndef __LINUX_KVM_S390_H
 #define __LINUX_KVM_S390_H
 
-/* s390 does not support KVM */
+/*
+ * asm-s390/kvm.h - KVM s390 specific structures and definitions
+ *
+ * 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 <asm/types.h>
+
+/* for KVM_GET_IRQCHIP and KVM_SET_IRQCHIP */
+struct kvm_pic_state {
+        /* no PIC for s390 */
+};
+
+struct kvm_ioapic_state {
+        /* no IOAPIC for s390 */
+};
+
+/* for KVM_GET_REGS and KVM_SET_REGS */
+struct kvm_regs {
+        /* general purpose regs for s390 */
+        __u64 gprs[16];
+};
+
+/* for KVM_GET_SREGS and KVM_SET_SREGS */
+struct kvm_sregs {
+        __u32 acrs[16];
+        __u64 crs[16];
+};
+
+/* for KVM_GET_FPU and KVM_SET_FPU */
+struct kvm_fpu {
+        __u32 fpc;
+        __u64 fprs[16];
+};
 
 #endif