2 files changed, 175 insertions, 2 deletions

diff --git a/include/asm-s390/kvm_para.h b/include/asm-s390/kvm_para.h
index e9bd3fbe878c..2c503796b619 100644
--- a/include/asm-s390/kvm_para.h
+++ b/include/asm-s390/kvm_para.h
@@ -14,14 +14,134 @@
 #define __S390_KVM_PARA_H
 
 /*
- * No hypercalls for KVM on s390
+ * Hypercalls for KVM on s390. The calling convention is similar to the
+ * s390 ABI, so we use R2-R6 for parameters 1-5. In addition we use R1
+ * as hypercall number and R7 as parameter 6. The return value is
+ * written to R2. We use the diagnose instruction as hypercall. To avoid
+ * conflicts with existing diagnoses for LPAR and z/VM, we do not use
+ * the instruction encoded number, but specify the number in R1 and
+ * use 0x500 as KVM hypercall
+ *
+ * Copyright IBM Corp. 2007,2008
+ * Author(s): Christian Borntraeger <borntraeger@de.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
  */
 
+static inline long kvm_hypercall0(unsigned long nr)
+{
+        register unsigned long __nr asm("1") = nr;
+        register long __rc asm("2");
+
+        asm volatile ("diag 2,4,0x500\n"
+                      : "=d" (__rc) : "d" (__nr): "memory", "cc");
+        return __rc;
+}
+
+static inline long kvm_hypercall1(unsigned long nr, unsigned long p1)
+{
+        register unsigned long __nr asm("1") = nr;
+        register unsigned long __p1 asm("2") = p1;
+        register long __rc asm("2");
+
+        asm volatile ("diag 2,4,0x500\n"
+                      : "=d" (__rc) : "d" (__nr), "0" (__p1) : "memory", "cc");
+        return __rc;
+}
+
+static inline long kvm_hypercall2(unsigned long nr, unsigned long p1,
+                               unsigned long p2)
+{
+        register unsigned long __nr asm("1") = nr;
+        register unsigned long __p1 asm("2") = p1;
+        register unsigned long __p2 asm("3") = p2;
+        register long __rc asm("2");
+
+        asm volatile ("diag 2,4,0x500\n"
+                      : "=d" (__rc) : "d" (__nr), "0" (__p1), "d" (__p2)
+                      : "memory", "cc");
+        return __rc;
+}
+
+static inline long kvm_hypercall3(unsigned long nr, unsigned long p1,
+                               unsigned long p2, unsigned long p3)
+{
+        register unsigned long __nr asm("1") = nr;
+        register unsigned long __p1 asm("2") = p1;
+        register unsigned long __p2 asm("3") = p2;
+        register unsigned long __p3 asm("4") = p3;
+        register long __rc asm("2");
+
+        asm volatile ("diag 2,4,0x500\n"
+                      : "=d" (__rc) : "d" (__nr), "0" (__p1), "d" (__p2),
+                        "d" (__p3) : "memory", "cc");
+        return __rc;
+}
+
+
+static inline long kvm_hypercall4(unsigned long nr, unsigned long p1,
+                               unsigned long p2, unsigned long p3,
+                               unsigned long p4)
+{
+        register unsigned long __nr asm("1") = nr;
+        register unsigned long __p1 asm("2") = p1;
+        register unsigned long __p2 asm("3") = p2;
+        register unsigned long __p3 asm("4") = p3;
+        register unsigned long __p4 asm("5") = p4;
+        register long __rc asm("2");
+
+        asm volatile ("diag 2,4,0x500\n"
+                      : "=d" (__rc) : "d" (__nr), "0" (__p1), "d" (__p2),
+                        "d" (__p3), "d" (__p4) : "memory", "cc");
+        return __rc;
+}
+
+static inline long kvm_hypercall5(unsigned long nr, unsigned long p1,
+                               unsigned long p2, unsigned long p3,
+                               unsigned long p4, unsigned long p5)
+{
+        register unsigned long __nr asm("1") = nr;
+        register unsigned long __p1 asm("2") = p1;
+        register unsigned long __p2 asm("3") = p2;
+        register unsigned long __p3 asm("4") = p3;
+        register unsigned long __p4 asm("5") = p4;
+        register unsigned long __p5 asm("6") = p5;
+        register long __rc asm("2");
+
+        asm volatile ("diag 2,4,0x500\n"
+                      : "=d" (__rc) : "d" (__nr), "0" (__p1), "d" (__p2),
+                        "d" (__p3), "d" (__p4), "d" (__p5)  : "memory", "cc");
+        return __rc;
+}
+
+static inline long kvm_hypercall6(unsigned long nr, unsigned long p1,
+                               unsigned long p2, unsigned long p3,
+                               unsigned long p4, unsigned long p5,
+                               unsigned long p6)
+{
+        register unsigned long __nr asm("1") = nr;
+        register unsigned long __p1 asm("2") = p1;
+        register unsigned long __p2 asm("3") = p2;
+        register unsigned long __p3 asm("4") = p3;
+        register unsigned long __p4 asm("5") = p4;
+        register unsigned long __p5 asm("6") = p5;
+        register unsigned long __p6 asm("7") = p6;
+        register long __rc asm("2");
+
+        asm volatile ("diag 2,4,0x500\n"
+                      : "=d" (__rc) : "d" (__nr), "0" (__p1), "d" (__p2),
+                        "d" (__p3), "d" (__p4), "d" (__p5), "d" (__p6)
+                      : "memory", "cc");
+        return __rc;
+}
+
+/* kvm on s390 is always paravirtualization enabled */
 static inline int kvm_para_available(void)
 {
-        return 0;
+        return 1;
 }
 
+/* No feature bits are currently assigned for kvm on s390 */
 static inline unsigned int kvm_arch_para_features(void)
 {
         return 0;
diff --git a/include/asm-s390/kvm_virtio.h b/include/asm-s390/kvm_virtio.h
new file mode 100644
index 000000000000..5c871a990c29
--- /dev/null
+++ b/include/asm-s390/kvm_virtio.h
@@ -0,0 +1,53 @@
+/*
+ * kvm_virtio.h - definition for virtio for kvm on s390
+ *
+ * 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): Christian Borntraeger <borntraeger@de.ibm.com>
+ */
+
+#ifndef __KVM_S390_VIRTIO_H
+#define __KVM_S390_VIRTIO_H
+
+#include <linux/types.h>
+
+struct kvm_device_desc {
+        /* The device type: console, network, disk etc.  Type 0 terminates. */
+        __u8 type;
+        /* The number of virtqueues (first in config array) */
+        __u8 num_vq;
+        /*
+         * The number of bytes of feature bits.  Multiply by 2: one for host
+         * features and one for guest acknowledgements.
+         */
+        __u8 feature_len;
+        /* The number of bytes of the config array after virtqueues. */
+        __u8 config_len;
+        /* A status byte, written by the Guest. */
+        __u8 status;
+        __u8 config[0];
+};
+
+/*
+ * This is how we expect the device configuration field for a virtqueue
+ * to be laid out in config space.
+ */
+struct kvm_vqconfig {
+        /* The token returned with an interrupt. Set by the guest */
+        __u64 token;
+        /* The address of the virtio ring */
+        __u64 address;
+        /* The number of entries in the virtio_ring */
+        __u16 num;
+
+};
+
+#define KVM_S390_VIRTIO_NOTIFY          0
+#define KVM_S390_VIRTIO_RESET           1
+#define KVM_S390_VIRTIO_SET_STATUS      2
+
+#endif