[PATCH v9 098/105] KVM: TDX: Handle TDX PV map_gpa hypercall

From: isaku . yamahata
Date: Fri Sep 30 2022 - 06:28:04 EST


From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>

Wire up TDX PV map_gpa hypercall to the kvm/mmu backend.

Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
---
arch/x86/kvm/vmx/tdx.c | 33 +++++++++++++++++++++++++++++++++
1 file changed, 33 insertions(+)

diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index a7cf08d60744..6318c0c09c0d 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1078,6 +1078,37 @@ static int tdx_report_fatal_error(struct kvm_vcpu *vcpu)
return 0;
}

+static int tdx_map_gpa(struct kvm_vcpu *vcpu)
+{
+ struct kvm *kvm = vcpu->kvm;
+ gpa_t gpa = tdvmcall_a0_read(vcpu);
+ gpa_t size = tdvmcall_a1_read(vcpu);
+ gpa_t end = gpa + size;
+ gfn_t s = gpa_to_gfn(gpa) & ~kvm_gfn_shared_mask(kvm);
+ gfn_t e = gpa_to_gfn(end) & ~kvm_gfn_shared_mask(kvm);
+ bool map_private = kvm_is_private_gpa(kvm, gpa);
+ int ret;
+
+ if (!IS_ALIGNED(gpa, 4096) || !IS_ALIGNED(size, 4096) ||
+ end < gpa ||
+ end > kvm_gfn_shared_mask(kvm) << (PAGE_SHIFT + 1) ||
+ kvm_is_private_gpa(kvm, gpa) != kvm_is_private_gpa(kvm, end)) {
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
+ return 1;
+ }
+
+ ret = kvm_mmu_map_gpa(vcpu, &s, e, map_private);
+ if (ret == -EAGAIN) {
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_RETRY);
+ tdvmcall_set_return_val(vcpu, gfn_to_gpa(s));
+ } else if (ret)
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
+ else
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_SUCCESS);
+
+ return 1;
+}
+
static int handle_tdvmcall(struct kvm_vcpu *vcpu)
{
if (tdvmcall_exit_type(vcpu))
@@ -1098,6 +1129,8 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu)
return tdx_emulate_wrmsr(vcpu);
case TDG_VP_VMCALL_REPORT_FATAL_ERROR:
return tdx_report_fatal_error(vcpu);
+ case TDG_VP_VMCALL_MAP_GPA:
+ return tdx_map_gpa(vcpu);
default:
break;
}
--
2.25.1