[PATCH v15 02/23] KVM: selftests: Update kvm_init_vm_address_properties() for TDX

[Lisa Wang <wyihan@google.com>]

From: Isaku Yamahata <isaku.yamahata@intel.com>

Initialize the TDX S-bit and the GPA tag mask in
kvm_init_vm_address_properties() for TDX VMs, similar to how the C-bit
is initialized for SEV VMs.

The TDX S-bit is used to distinguish between shared and private guest
physical addresses. Its position is determined by the guest physical
address width, which is either 48 or 52 bits for current TDX
implementations.

Co-developed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Co-developed-by: Sagi Shahar <sagis@google.com>
Signed-off-by: Sagi Shahar <sagis@google.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Lisa Wang <wyihan@google.com>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
---
 tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h | 14 ++++++++++++++
 tools/testing/selftests/kvm/lib/x86/processor.c        | 12 ++++++++++--
 2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
new file mode 100644
index 000000000000..f647e6ca6b34
--- /dev/null
+++ b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef SELFTESTS_TDX_TDX_UTIL_H
+#define SELFTESTS_TDX_TDX_UTIL_H
+
+#include <stdbool.h>
+
+#include "kvm_util.h"
+
+static inline bool is_tdx_vm(struct kvm_vm *vm)
+{
+	return vm->type == KVM_X86_TDX_VM;
+}
+
+#endif /* SELFTESTS_TDX_TDX_UTIL_H */
diff --git a/tools/testing/selftests/kvm/lib/x86/processor.c b/tools/testing/selftests/kvm/lib/x86/processor.c
index d31fa81ea075..24395a8e654a 100644
--- a/tools/testing/selftests/kvm/lib/x86/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86/processor.c
@@ -11,6 +11,7 @@
 #include "smm.h"
 #include "svm_util.h"
 #include "sev.h"
+#include "tdx/tdx_util.h"
 #include "vmx.h"
 
 #ifndef NUM_INTERRUPTS
@@ -1330,12 +1331,19 @@ void kvm_get_cpu_address_width(unsigned int *pa_bits, unsigned int *va_bits)
 
 void kvm_init_vm_address_properties(struct kvm_vm *vm)
 {
+	u32 gpa_bits = kvm_cpu_property(X86_PROPERTY_GUEST_MAX_PHY_ADDR);
+
+	vm->arch.sev_fd = -1;
+
 	if (is_sev_vm(vm)) {
 		vm->arch.sev_fd = open_sev_dev_path_or_exit();
 		vm->arch.c_bit = BIT_ULL(this_cpu_property(X86_PROPERTY_SEV_C_BIT));
 		vm->gpa_tag_mask = vm->arch.c_bit;
-	} else {
-		vm->arch.sev_fd = -1;
+	} else if (is_tdx_vm(vm)) {
+		TEST_ASSERT(gpa_bits == 48 || gpa_bits == 52,
+			    "TDX: bad X86_PROPERTY_GUEST_MAX_PHY_ADDR value: %u", gpa_bits);
+		vm->arch.s_bit = BIT_ULL(gpa_bits - 1);
+		vm->gpa_tag_mask = vm->arch.s_bit;
 	}
 }
 

-- 
2.56.0.rc1.315.gc6ed9934b7-goog