target-i386/kvm: Hyper-V VMBus hypercalls blank handlers

Add Hyper-V VMBus hypercalls blank handlers which
just returns error code - HV_STATUS_INVALID_HYPERCALL_CODE.
This is required when the synthetic interrupt controller is
active.

Fixes: 50efe82cSigned-off-by: NAndrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Eduardo Habkost <ehabkost@redhat.com>
CC: "Andreas Färber" <afaerber@suse.de>
CC: Marcelo Tosatti <mtosatti@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: kvm@vger.kernel.org
Message-Id: <1456309368-29769-2-git-send-email-asmetanin@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

target-i386/hyperv.c

@@ -44,6 +44,18 @@ int kvm_hv_handle_exit(X86CPU *cpu, struct kvm_hyperv_exit *exit)
             return -1;
         }
         return 0;
+    case KVM_EXIT_HYPERV_HCALL: {
+        uint16_t code;
+
+        code  = exit->u.hcall.input & 0xffff;
+        switch (code) {
+        case HVCALL_POST_MESSAGE:
+        case HVCALL_SIGNAL_EVENT:
+        default:
+            exit->u.hcall.result = HV_STATUS_INVALID_HYPERCALL_CODE;
+            return 0;
+        }
+    }
     default:
         return -1;
     }