[PATCH v1 05/40] i386/tdx: Implement tdx_kvm_init() to initialize TDX VM context

Xiaoyao Li
2022-08-02T07:48:35Z

Introduce tdx_kvm_init() and invoke it in kvm_confidential_guest_init()
if it's a TDX VM. More initialization will be added later.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
---
target/i386/kvm/kvm.c | 15 ++++++---------
target/i386/kvm/meson.build | 2 +-
target/i386/kvm/tdx-stub.c | 9 +++++++++
target/i386/kvm/tdx.c | 7 +++++++
target/i386/kvm/tdx.h | 2 ++
5 files changed, 25 insertions(+), 10 deletions(-)
create mode 100644 target/i386/kvm/tdx-stub.c

diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index 1f4a6a4dff28..335f87e6cc59 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -54,6 +54,7 @@
#include "migration/blocker.h"
#include "exec/memattrs.h"
#include "trace.h"
+#include "tdx.h"

#include CONFIG_DEVICES

@@ -2452,6 +2453,8 @@ static int kvm_confidential_guest_init(MachineState *ms, Error **errp)
{
if (object_dynamic_cast(OBJECT(ms->cgs), TYPE_SEV_GUEST)) {
return sev_kvm_init(ms->cgs, errp);
+ } else if (object_dynamic_cast(OBJECT(ms->cgs), TYPE_TDX_GUEST)) {
+ return tdx_kvm_init(ms, errp);
}

return 0;
@@ -2466,16 +2469,10 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
Error *local_err = NULL;

/*
- * Initialize SEV context, if required
+ * Initialize confidential guest (SEV/TDX) context, if required
*
- * If no memory encryption is requested (ms->cgs == NULL) this is
- * a no-op.
- *
- * It's also a no-op if a non-SEV confidential guest support
- * mechanism is selected. SEV is the only mechanism available to
- * select on x86 at present, so this doesn't arise, but if new
- * mechanisms are supported in future (e.g. TDX), they'll need
- * their own initialization either here or elsewhere.
+ * It's a no-op if a non-SEV/non-tdx confidential guest support
+ * mechanism is selected, i.e., ms->cgs == NULL
*/
ret = kvm_confidential_guest_init(ms, &local_err);
if (ret < 0) {
diff --git a/target/i386/kvm/meson.build b/target/i386/kvm/meson.build
index b2d7d41acde2..fd30b93ecec9 100644
--- a/target/i386/kvm/meson.build
+++ b/target/i386/kvm/meson.build
@@ -9,7 +9,7 @@ i386_softmmu_kvm_ss.add(files(

i386_softmmu_kvm_ss.add(when: 'CONFIG_SEV', if_false: files('sev-stub.c'))

-i386_softmmu_kvm_ss.add(when: 'CONFIG_TDX', if_true: files('tdx.c'))
+i386_softmmu_kvm_ss.add(when: 'CONFIG_TDX', if_true: files('tdx.c'), if_false: files('tdx-stub.c'))

i386_softmmu_ss.add(when: 'CONFIG_HYPERV', if_true: files('hyperv.c'), if_false: files('hyperv-stub.c'))

diff --git a/target/i386/kvm/tdx-stub.c b/target/i386/kvm/tdx-stub.c
new file mode 100644
index 000000000000..1df24735201e
--- /dev/null
+++ b/target/i386/kvm/tdx-stub.c
@@ -0,0 +1,9 @@
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+
+#include "tdx.h"
+
+int tdx_kvm_init(MachineState *ms, Error **errp)
+{
+ return -EINVAL;
+}
diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index d3792d4a3d56..77e33ae01147 100644
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -12,10 +12,17 @@
*/

#include "qemu/osdep.h"
+#include "qapi/error.h"
#include "qom/object_interfaces.h"

+#include "hw/i386/x86.h"
#include "tdx.h"

+int tdx_kvm_init(MachineState *ms, Error **errp)
+{
+ return 0;
+}
+
/* tdx guest */
OBJECT_DEFINE_TYPE_WITH_INTERFACES(TdxGuest,
tdx_guest,
diff --git a/target/i386/kvm/tdx.h b/target/i386/kvm/tdx.h
index 415aeb5af746..c8a23d95258d 100644
--- a/target/i386/kvm/tdx.h
+++ b/target/i386/kvm/tdx.h
@@ -16,4 +16,6 @@ typedef struct TdxGuest {
uint64_t attributes; /* TD attributes */
} TdxGuest;

+int tdx_kvm_init(MachineState *ms, Error **errp);
+
#endif /* QEMU_I386_TDX_H */
--
2.27.0