s390x: protvirt: Support unpack facility

The unpack facility provides the means to setup a protected guest. A
protected guest cannot be introspected by the hypervisor or any
user/administrator of the machine it is running on.

Protected guests are encrypted at rest and need a special boot
mechanism via diag308 subcode 8 and 10.

Code 8 sets the PV specific IPLB which is retained separately from
those set via code 5.

Code 10 is used to unpack the VM into protected memory, verify its
integrity and start it.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Co-developed-by: Christian Borntraeger <borntraeger@de.ibm.com> [Changes
to machine]
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200323083606.24520-1-frankja@linux.ibm.com>
[CH: fixed up KVM_PV_VM_ -> KVM_PV_]
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

1 files changed, 98 insertions, 0 deletions

diff --git a/hw/s390x/pv.c b/hw/s390x/pv.c
new file mode 100644
index 0000000000..a40a844806
--- /dev/null
+++ b/hw/s390x/pv.c
@@ -0,0 +1,98 @@
+/*
+ * Protected Virtualization functions
+ *
+ * Copyright IBM Corp. 2020
+ * Author(s):
+ *  Janosch Frank <frankja@linux.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or (at
+ * your option) any later version. See the COPYING file in the top-level
+ * directory.
+ */
+#include "qemu/osdep.h"
+
+#include <linux/kvm.h>
+
+#include "qemu/error-report.h"
+#include "sysemu/kvm.h"
+#include "hw/s390x/pv.h"
+
+static int __s390_pv_cmd(uint32_t cmd, const char *cmdname, void *data)
+{
+    struct kvm_pv_cmd pv_cmd = {
+        .cmd = cmd,
+        .data = (uint64_t)data,
+    };
+    int rc = kvm_vm_ioctl(kvm_state, KVM_S390_PV_COMMAND, &pv_cmd);
+
+    if (rc) {
+        error_report("KVM PV command %d (%s) failed: header rc %x rrc %x "
+                     "IOCTL rc: %d", cmd, cmdname, pv_cmd.rc, pv_cmd.rrc,
+                     rc);
+    }
+    return rc;
+}
+
+/*
+ * This macro lets us pass the command as a string to the function so
+ * we can print it on an error.
+ */
+#define s390_pv_cmd(cmd, data) __s390_pv_cmd(cmd, #cmd, data);
+#define s390_pv_cmd_exit(cmd, data)    \
+{                                      \
+    int rc;                            \
+                                       \
+    rc = __s390_pv_cmd(cmd, #cmd, data);\
+    if (rc) {                          \
+        exit(1);                       \
+    }                                  \
+}
+
+int s390_pv_vm_enable(void)
+{
+    return s390_pv_cmd(KVM_PV_ENABLE, NULL);
+}
+
+void s390_pv_vm_disable(void)
+{
+     s390_pv_cmd_exit(KVM_PV_DISABLE, NULL);
+}
+
+int s390_pv_set_sec_parms(uint64_t origin, uint64_t length)
+{
+    struct kvm_s390_pv_sec_parm args = {
+        .origin = origin,
+        .length = length,
+    };
+
+    return s390_pv_cmd(KVM_PV_SET_SEC_PARMS, &args);
+}
+
+/*
+ * Called for each component in the SE type IPL parameter block 0.
+ */
+int s390_pv_unpack(uint64_t addr, uint64_t size, uint64_t tweak)
+{
+    struct kvm_s390_pv_unp args = {
+        .addr = addr,
+        .size = size,
+        .tweak = tweak,
+    };
+
+    return s390_pv_cmd(KVM_PV_UNPACK, &args);
+}
+
+void s390_pv_perf_clear_reset(void)
+{
+    s390_pv_cmd_exit(KVM_PV_PREP_RESET, NULL);
+}
+
+int s390_pv_verify(void)
+{
+    return s390_pv_cmd(KVM_PV_VERIFY, NULL);
+}
+
+void s390_pv_unshare(void)
+{
+    s390_pv_cmd_exit(KVM_PV_UNSHARE_ALL, NULL);
+}