[PATCH v3 19/70] i386/tdx: Introduce is_tdx_vm() helper and cache tdx_guest object

Xiaoyao Li
2023-11-15T07:17:41Z

It will need special handling for TDX VMs all around the QEMU.
Introduce is_tdx_vm() helper to query if it's a TDX VM.

Cache tdx_guest object thus no need to cast from ms->cgs every time.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
---
changes in v3:
- replace object_dynamic_cast with TDX_GUEST();
---
target/i386/kvm/tdx.c | 15 ++++++++++++++-
target/i386/kvm/tdx.h | 10 ++++++++++
2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index cb0040187b27..cf8889f0a8f9 100644
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -21,8 +21,16 @@
#include "kvm_i386.h"
#include "tdx.h"

+static TdxGuest *tdx_guest;
+
static struct kvm_tdx_capabilities *tdx_caps;

+/* It's valid after kvm_confidential_guest_init()->kvm_tdx_init() */
+bool is_tdx_vm(void)
+{
+ return !!tdx_guest;
+}
+
enum tdx_ioctl_level{
TDX_PLATFORM_IOCTL,
TDX_VM_IOCTL,
@@ -114,15 +122,20 @@ static int get_tdx_capabilities(Error **errp)

int tdx_kvm_init(MachineState *ms, Error **errp)
{
+ TdxGuest *tdx = TDX_GUEST(OBJECT(ms->cgs));
int r = 0;

ms->require_guest_memfd = true;

if (!tdx_caps) {
r = get_tdx_capabilities(errp);
+ if (r) {
+ return r;
+ }
}

- return r;
+ tdx_guest = tdx;
+ return 0;
}

/* tdx guest */
diff --git a/target/i386/kvm/tdx.h b/target/i386/kvm/tdx.h
index c8a23d95258d..4036ca2f3f99 100644
--- a/target/i386/kvm/tdx.h
+++ b/target/i386/kvm/tdx.h
@@ -1,6 +1,10 @@
#ifndef QEMU_I386_TDX_H
#define QEMU_I386_TDX_H

+#ifndef CONFIG_USER_ONLY
+#include CONFIG_DEVICES /* CONFIG_TDX */
+#endif
+
#include "exec/confidential-guest-support.h"

#define TYPE_TDX_GUEST "tdx-guest"
@@ -16,6 +20,12 @@ typedef struct TdxGuest {
uint64_t attributes; /* TD attributes */
} TdxGuest;

+#ifdef CONFIG_TDX
+bool is_tdx_vm(void);
+#else
+#define is_tdx_vm() 0
+#endif /* CONFIG_TDX */
+
int tdx_kvm_init(MachineState *ms, Error **errp);

#endif /* QEMU_I386_TDX_H */
--
2.34.1