[PATCH RFC 05/19] KVM: x86: Prepare kvm_hv_flush_tlb() to handle L2's GPAs

[Vitaly Kuznetsov]

To handle Direct TLB flush requests from L2, KVM needs to translate the
specified L2 GPA to L1 GPA to read hypercall arguments from there.

No fucntional change as KVM doesn't handle VMCALL/VMMCALL from L2 yet.

Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
---
 arch/x86/kvm/hyperv.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index f619acccbb6d..53eb9540494b 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -23,6 +23,7 @@
 #include "ioapic.h"
 #include "cpuid.h"
 #include "hyperv.h"
+#include "mmu.h"
 #include "xen.h"
 
 #include <linux/cpu.h>
@@ -1969,6 +1970,12 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
 	 */
 	BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > 64);
 
+	if (!hc->fast && is_guest_mode(vcpu)) {
+		hc->ingpa = translate_nested_gpa(vcpu, hc->ingpa, 0, NULL);
+		if (unlikely(hc->ingpa == UNMAPPED_GVA))
+			return HV_STATUS_INVALID_HYPERCALL_INPUT;
+	}
+
 	if (hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST ||
 	    hc->code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE) {
 		if (hc->fast) {
-- 
2.35.1