KVM: SVM: use kvm_register_write()/read()

KVM has nice wrappers to access the register values, clean up a few places
that should use them but currently do not.
Signed-off-by: David Kaplan <david.kaplan@amd.com>
[forward port and testing]
Signed-off-by: Joel Schopp <joel.schopp@amd.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

arch/x86/kvm/svm.c

@@ -2757,11 +2757,11 @@ static int invlpga_interception(struct vcpu_svm *svm)
 {
 	struct kvm_vcpu *vcpu = &svm->vcpu;
 
-	trace_kvm_invlpga(svm->vmcb->save.rip, vcpu->arch.regs[VCPU_REGS_RCX],
-			  vcpu->arch.regs[VCPU_REGS_RAX]);
+	trace_kvm_invlpga(svm->vmcb->save.rip, kvm_register_read(&svm->vcpu, VCPU_REGS_RCX),
+			  kvm_register_read(&svm->vcpu, VCPU_REGS_RAX));
 
 	/* Let's treat INVLPGA the same as INVLPG (can be optimized!) */
-	kvm_mmu_invlpg(vcpu, vcpu->arch.regs[VCPU_REGS_RAX]);
+	kvm_mmu_invlpg(vcpu, kvm_register_read(&svm->vcpu, VCPU_REGS_RAX));
 
 	svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
 	skip_emulated_instruction(&svm->vcpu);
@@ -2770,7 +2770,7 @@ static int invlpga_interception(struct vcpu_svm *svm)
 
 static int skinit_interception(struct vcpu_svm *svm)
 {
-	trace_kvm_skinit(svm->vmcb->save.rip, svm->vcpu.arch.regs[VCPU_REGS_RAX]);
+	trace_kvm_skinit(svm->vmcb->save.rip, kvm_register_read(&svm->vcpu, VCPU_REGS_RAX));
 
 	kvm_queue_exception(&svm->vcpu, UD_VECTOR);
 	return 1;
@@ -3133,7 +3133,7 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, unsigned ecx, u64 *data)
 
 static int rdmsr_interception(struct vcpu_svm *svm)
 {
-	u32 ecx = svm->vcpu.arch.regs[VCPU_REGS_RCX];
+	u32 ecx = kvm_register_read(&svm->vcpu, VCPU_REGS_RCX);
 	u64 data;
 
 	if (svm_get_msr(&svm->vcpu, ecx, &data)) {
@@ -3142,8 +3142,8 @@ static int rdmsr_interception(struct vcpu_svm *svm)
 	} else {
 		trace_kvm_msr_read(ecx, data);
 
-		svm->vcpu.arch.regs[VCPU_REGS_RAX] = data & 0xffffffff;
-		svm->vcpu.arch.regs[VCPU_REGS_RDX] = data >> 32;
+		kvm_register_write(&svm->vcpu, VCPU_REGS_RAX, data & 0xffffffff);
+		kvm_register_write(&svm->vcpu, VCPU_REGS_RDX, data >> 32);
 		svm->next_rip = kvm_rip_read(&svm->vcpu) + 2;
 		skip_emulated_instruction(&svm->vcpu);
 	}
@@ -3246,9 +3246,8 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
 static int wrmsr_interception(struct vcpu_svm *svm)
 {
 	struct msr_data msr;
-	u32 ecx = svm->vcpu.arch.regs[VCPU_REGS_RCX];
-	u64 data = (svm->vcpu.arch.regs[VCPU_REGS_RAX] & -1u)
-		| ((u64)(svm->vcpu.arch.regs[VCPU_REGS_RDX] & -1u) << 32);
+	u32 ecx = kvm_register_read(&svm->vcpu, VCPU_REGS_RCX);
+	u64 data = kvm_read_edx_eax(&svm->vcpu);
 
 	msr.data = data;
 	msr.index = ecx;