KVM: MMU: cleanup for kvm_mmu_page_unlink_children

Cleanup the same operation between kvm_mmu_page_unlink_children and
mmu_pte_write_zap_pte

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

1 files changed, 23 insertions, 43 deletions

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 9eaca1c739a6..71eddc4c9810 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1566,32 +1566,33 @@ static void validate_direct_spte(struct kvm_vcpu *vcpu, u64 *sptep,
         }
 }
 
+static void mmu_page_zap_pte(struct kvm *kvm, struct kvm_mmu_page *sp,
+                             u64 *spte)
+{
+        u64 pte;
+        struct kvm_mmu_page *child;
+
+        pte = *spte;
+        if (is_shadow_present_pte(pte)) {
+                if (is_last_spte(pte, sp->role.level))
+                        drop_spte(kvm, spte, shadow_trap_nonpresent_pte);
+                else {
+                        child = page_header(pte & PT64_BASE_ADDR_MASK);
+                        mmu_page_remove_parent_pte(child, spte);
+                }
+        }
+        __set_spte(spte, shadow_trap_nonpresent_pte);
+        if (is_large_pte(pte))
+                --kvm->stat.lpages;
+}
+
 static void kvm_mmu_page_unlink_children(struct kvm *kvm,
                                          struct kvm_mmu_page *sp)
 {
         unsigned i;
-        u64 *pt;
-        u64 ent;
-
-        pt = sp->spt;
 
-        for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
-                ent = pt[i];
-
-                if (is_shadow_present_pte(ent)) {
-                        if (!is_last_spte(ent, sp->role.level)) {
-                                ent &= PT64_BASE_ADDR_MASK;
-                                mmu_page_remove_parent_pte(page_header(ent),
-                                                           &pt[i]);
-                        } else {
-                                if (is_large_pte(ent))
-                                        --kvm->stat.lpages;
-                                drop_spte(kvm, &pt[i],
-                                          shadow_trap_nonpresent_pte);
-                        }
-                }
-                pt[i] = shadow_trap_nonpresent_pte;
-        }
+        for (i = 0; i < PT64_ENT_PER_PAGE; ++i)
+                mmu_page_zap_pte(kvm, sp, sp->spt + i);
 }
 
 static void kvm_mmu_put_page(struct kvm_mmu_page *sp, u64 *parent_pte)
@@ -3069,27 +3070,6 @@ void kvm_mmu_unload(struct kvm_vcpu *vcpu)
 }
 EXPORT_SYMBOL_GPL(kvm_mmu_unload);
 
-static void mmu_pte_write_zap_pte(struct kvm_vcpu *vcpu,
-                                  struct kvm_mmu_page *sp,
-                                  u64 *spte)
-{
-        u64 pte;
-        struct kvm_mmu_page *child;
-
-        pte = *spte;
-        if (is_shadow_present_pte(pte)) {
-                if (is_last_spte(pte, sp->role.level))
-                        drop_spte(vcpu->kvm, spte, shadow_trap_nonpresent_pte);
-                else {
-                        child = page_header(pte & PT64_BASE_ADDR_MASK);
-                        mmu_page_remove_parent_pte(child, spte);
-                }
-        }
-        __set_spte(spte, shadow_trap_nonpresent_pte);
-        if (is_large_pte(pte))
-                --vcpu->kvm->stat.lpages;
-}
-
 static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu,
                                   struct kvm_mmu_page *sp, u64 *spte,
                                   const void *new)
@@ -3271,7 +3251,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
                 spte = &sp->spt[page_offset / sizeof(*spte)];
                 while (npte--) {
                         entry = *spte;
-                        mmu_pte_write_zap_pte(vcpu, sp, spte);
+                        mmu_page_zap_pte(vcpu->kvm, sp, spte);
                         if (gentry &&
                               !((sp->role.word ^ vcpu->arch.mmu.base_role.word)
                               & mask.word))