KVM: Replace reads of vcpu->arch.cr3 by an accessor

This allows us to keep cr3 in the VMCS, later on.

Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7ad9cda..6e50314 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -473,8 +473,8 @@
 		      (unsigned long *)&vcpu->arch.regs_avail))
 		return true;
 
-	gfn = (vcpu->arch.cr3 & ~31u) >> PAGE_SHIFT;
-	offset = (vcpu->arch.cr3 & ~31u) & (PAGE_SIZE - 1);
+	gfn = (kvm_read_cr3(vcpu) & ~31u) >> PAGE_SHIFT;
+	offset = (kvm_read_cr3(vcpu) & ~31u) & (PAGE_SIZE - 1);
 	r = kvm_read_nested_guest_page(vcpu, gfn, pdpte, offset, sizeof(pdpte),
 				       PFERR_USER_MASK | PFERR_WRITE_MASK);
 	if (r < 0)
@@ -519,7 +519,7 @@
 		} else
 #endif
 		if (is_pae(vcpu) && !load_pdptrs(vcpu, vcpu->arch.walk_mmu,
-						 vcpu->arch.cr3))
+						 kvm_read_cr3(vcpu)))
 			return 1;
 	}
 
@@ -611,7 +611,8 @@
 			return 1;
 	} else if (is_paging(vcpu) && (cr4 & X86_CR4_PAE)
 		   && ((cr4 ^ old_cr4) & pdptr_bits)
-		   && !load_pdptrs(vcpu, vcpu->arch.walk_mmu, vcpu->arch.cr3))
+		   && !load_pdptrs(vcpu, vcpu->arch.walk_mmu,
+				   kvm_read_cr3(vcpu)))
 		return 1;
 
 	if (cr4 & X86_CR4_VMXE)
@@ -631,7 +632,7 @@
 
 int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
 {
-	if (cr3 == vcpu->arch.cr3 && !pdptrs_changed(vcpu)) {
+	if (cr3 == kvm_read_cr3(vcpu) && !pdptrs_changed(vcpu)) {
 		kvm_mmu_sync_roots(vcpu);
 		kvm_mmu_flush_tlb(vcpu);
 		return 0;
@@ -4073,7 +4074,7 @@
 		value = vcpu->arch.cr2;
 		break;
 	case 3:
-		value = vcpu->arch.cr3;
+		value = kvm_read_cr3(vcpu);
 		break;
 	case 4:
 		value = kvm_read_cr4(vcpu);
@@ -5512,7 +5513,7 @@
 
 	sregs->cr0 = kvm_read_cr0(vcpu);
 	sregs->cr2 = vcpu->arch.cr2;
-	sregs->cr3 = vcpu->arch.cr3;
+	sregs->cr3 = kvm_read_cr3(vcpu);
 	sregs->cr4 = kvm_read_cr4(vcpu);
 	sregs->cr8 = kvm_get_cr8(vcpu);
 	sregs->efer = vcpu->arch.efer;
@@ -5580,7 +5581,7 @@
 	kvm_x86_ops->set_gdt(vcpu, &dt);
 
 	vcpu->arch.cr2 = sregs->cr2;
-	mmu_reset_needed |= vcpu->arch.cr3 != sregs->cr3;
+	mmu_reset_needed |= kvm_read_cr3(vcpu) != sregs->cr3;
 	vcpu->arch.cr3 = sregs->cr3;
 
 	kvm_set_cr8(vcpu, sregs->cr8);
@@ -5598,7 +5599,7 @@
 	if (sregs->cr4 & X86_CR4_OSXSAVE)
 		update_cpuid(vcpu);
 	if (!is_long_mode(vcpu) && is_pae(vcpu)) {
-		load_pdptrs(vcpu, vcpu->arch.walk_mmu, vcpu->arch.cr3);
+		load_pdptrs(vcpu, vcpu->arch.walk_mmu, kvm_read_cr3(vcpu));
 		mmu_reset_needed = 1;
 	}