From: Sean Christopherson <[email protected]>
Implement an ioctl to get system-wide parameters for TDX. Although the
function is systemwide, vm scoped mem_enc ioctl works for userspace VMM
like qemu and device scoped version is not define, re-use vm scoped
mem_enc.
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Isaku Yamahata <[email protected]>
---
arch/x86/include/uapi/asm/kvm.h | 20 +++++++++++
arch/x86/kvm/vmx/tdx.c | 45 +++++++++++++++++++++++++
tools/arch/x86/include/uapi/asm/kvm.h | 48 +++++++++++++++++++++++++++
3 files changed, 113 insertions(+)
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index 4eb345c3e5ce..bf522e8e461b 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -593,4 +593,24 @@ struct kvm_tdx_cmd {
__u64 unused;
};
+struct kvm_tdx_cpuid_config {
+ __u32 leaf;
+ __u32 sub_leaf;
+ __u32 eax;
+ __u32 ebx;
+ __u32 ecx;
+ __u32 edx;
+};
+
+struct kvm_tdx_capabilities {
+ __u64 attrs_fixed0;
+ __u64 attrs_fixed1;
+ __u64 xfam_fixed0;
+ __u64 xfam_fixed1;
+
+ __u32 nr_cpuid_configs;
+ __u32 padding;
+ struct kvm_tdx_cpuid_config cpuid_configs[0];
+};
+
#endif /* _ASM_X86_KVM_H */
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 54e5422ea73a..cf320459574f 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -16,6 +16,48 @@
offsetof(struct tdsysinfo_struct, cpuid_configs)) \
/ sizeof(struct tdx_cpuid_config))
+static int tdx_get_capabilities(struct kvm_tdx_cmd *cmd)
+{
+ struct kvm_tdx_capabilities __user *user_caps;
+ const struct tdsysinfo_struct *tdsysinfo;
+ struct kvm_tdx_capabilities caps;
+
+ BUILD_BUG_ON(sizeof(struct kvm_tdx_cpuid_config) !=
+ sizeof(struct tdx_cpuid_config));
+
+ if (cmd->flags)
+ return -EINVAL;
+
+ tdsysinfo = tdx_get_sysinfo();
+ if (!tdsysinfo)
+ return -ENOTSUPP;
+
+ user_caps = (void __user *)cmd->data;
+ if (copy_from_user(&caps, user_caps, sizeof(caps)))
+ return -EFAULT;
+
+ if (caps.nr_cpuid_configs < tdsysinfo->num_cpuid_config)
+ return -E2BIG;
+
+ caps = (struct kvm_tdx_capabilities) {
+ .attrs_fixed0 = tdsysinfo->attributes_fixed0,
+ .attrs_fixed1 = tdsysinfo->attributes_fixed1,
+ .xfam_fixed0 = tdsysinfo->xfam_fixed0,
+ .xfam_fixed1 = tdsysinfo->xfam_fixed1,
+ .nr_cpuid_configs = tdsysinfo->num_cpuid_config,
+ .padding = 0,
+ };
+
+ if (copy_to_user(user_caps, &caps, sizeof(caps)))
+ return -EFAULT;
+ if (copy_to_user(user_caps->cpuid_configs, &tdsysinfo->cpuid_configs,
+ tdsysinfo->num_cpuid_config *
+ sizeof(struct tdx_cpuid_config)))
+ return -EFAULT;
+
+ return 0;
+}
+
int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
{
struct kvm_tdx_cmd tdx_cmd;
@@ -29,6 +71,9 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
mutex_lock(&kvm->lock);
switch (tdx_cmd.id) {
+ case KVM_TDX_CAPABILITIES:
+ r = tdx_get_capabilities(&tdx_cmd);
+ break;
default:
r = -EINVAL;
goto out;
diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h
index 3e92f1057b51..bf522e8e461b 100644
--- a/tools/arch/x86/include/uapi/asm/kvm.h
+++ b/tools/arch/x86/include/uapi/asm/kvm.h
@@ -565,4 +565,52 @@ struct kvm_pmu_event_filter {
#define KVM_X86_DEFAULT_VM 0
#define KVM_X86_PROTECTED_VM 1
+/* Trust Domain eXtension sub-ioctl() commands. */
+enum kvm_tdx_cmd_id {
+ KVM_TDX_CAPABILITIES = 0,
+
+ KVM_TDX_CMD_NR_MAX,
+};
+
+struct kvm_tdx_cmd {
+ /* enum kvm_tdx_cmd_id */
+ __u32 id;
+ /* flags for sub-commend. If sub-command doesn't use this, set zero. */
+ __u32 flags;
+ /*
+ * data for each sub-command. An immediate or a pointer to the actual
+ * data in process virtual address. If sub-command doesn't use it,
+ * set zero.
+ */
+ __u64 data;
+ /*
+ * Auxiliary error code. The sub-command may return TDX SEAMCALL
+ * status code in addition to -Exxx.
+ * Defined for consistency with struct kvm_sev_cmd.
+ */
+ __u64 error;
+ /* Reserved: Defined for consistency with struct kvm_sev_cmd. */
+ __u64 unused;
+};
+
+struct kvm_tdx_cpuid_config {
+ __u32 leaf;
+ __u32 sub_leaf;
+ __u32 eax;
+ __u32 ebx;
+ __u32 ecx;
+ __u32 edx;
+};
+
+struct kvm_tdx_capabilities {
+ __u64 attrs_fixed0;
+ __u64 attrs_fixed1;
+ __u64 xfam_fixed0;
+ __u64 xfam_fixed1;
+
+ __u32 nr_cpuid_configs;
+ __u32 padding;
+ struct kvm_tdx_cpuid_config cpuid_configs[0];
+};
+
#endif /* _ASM_X86_KVM_H */
--
2.25.1