[PATCH 3/5] KVM: MMU: Unify 32-pae and single-root mmu setup

[Avi Kivity <avi@redhat.com>]

Reduce code duplication.

Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/mmu.c |   44 +++++++++++++++++++++-----------------------
 1 files changed, 21 insertions(+), 23 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index ddfa865..4da4ff1 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2052,41 +2052,36 @@ static int mmu_alloc_roots(struct kvm_vcpu *vcpu)
 	struct kvm_mmu_page *sp;
 	int direct = 0;
 	u64 pdptr;
+	hpa_t *rootp, root, root_flags;
+	int nr_roots;
 
-	root_gfn = vcpu->arch.cr3 >> PAGE_SHIFT;
+	direct = tdp_enabled || !is_paging(vcpu);
 
 	if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) {
-		hpa_t root = vcpu->arch.mmu.root_hpa;
-
-		ASSERT(!VALID_PAGE(root));
-		if (tdp_enabled)
-			direct = 1;
-		if (mmu_check_root(vcpu, root_gfn))
-			return 1;
-		sp = kvm_mmu_get_page(vcpu, root_gfn, 0,
-				      PT64_ROOT_LEVEL, direct,
-				      ACC_ALL, NULL);
-		root = __pa(sp->spt);
-		++sp->root_count;
-		vcpu->arch.mmu.root_hpa = root;
-		return 0;
+		rootp = &vcpu->arch.mmu.root_hpa;
+		nr_roots = 1;
+		root_flags = 0;
+	} else {
+		rootp = vcpu->arch.mmu.pae_root;
+		nr_roots = 4;
+		root_flags = PT_PRESENT_MASK;
 	}
-	direct = !is_paging(vcpu);
-	if (tdp_enabled)
-		direct = 1;
-	for (i = 0; i < 4; ++i) {
-		hpa_t root = vcpu->arch.mmu.pae_root[i];
 
+	for (i = 0; i < nr_roots; ++i) {
+		root = rootp[i];
 		ASSERT(!VALID_PAGE(root));
 		if (vcpu->arch.mmu.root_level == PT32E_ROOT_LEVEL) {
 			pdptr = kvm_pdptr_read(vcpu, i);
 			if (!is_present_gpte(pdptr)) {
-				vcpu->arch.mmu.pae_root[i] = 0;
+				rootp[i] = 0;
 				continue;
 			}
 			root_gfn = pdptr >> PAGE_SHIFT;
 		} else if (vcpu->arch.mmu.root_level == 0)
 			root_gfn = 0;
+		else
+			root_gfn = vcpu->arch.cr3 >> PAGE_SHIFT;
+
 		if (mmu_check_root(vcpu, root_gfn))
 			return 1;
 		sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30,
@@ -2094,9 +2089,12 @@ static int mmu_alloc_roots(struct kvm_vcpu *vcpu)
 				      ACC_ALL, NULL);
 		root = __pa(sp->spt);
 		++sp->root_count;
-		vcpu->arch.mmu.pae_root[i] = root | PT_PRESENT_MASK;
+		rootp[i] = root | root_flags;
 	}
-	vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root);
+
+	if (nr_roots == 4)
+		vcpu->arch.mmu.root_hpa = __pa(rootp);
+
 	return 0;
 }
 
-- 
1.7.0.4