KVM: MMU: introduce kvm_mmu_flush_or_zap

This is a generalization of mmu_pte_write_flush_tlb, that also
takes care of calling kvm_mmu_commit_zap_page.  The next
patches will introduce more uses.

Reviewed-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 0a4dc9b..6dae235 100644 (file)
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -4188,11 +4188,14 @@ static bool need_remote_flush(u64 old, u64 new)
        return (old & ~new & PT64_PERM_MASK) != 0;
 }
 
-static void mmu_pte_write_flush_tlb(struct kvm_vcpu *vcpu, bool zap_page,
-                                   bool remote_flush, bool local_flush)
+static void kvm_mmu_flush_or_zap(struct kvm_vcpu *vcpu,
+                                struct list_head *invalid_list,
+                                bool remote_flush, bool local_flush)
 {
-       if (zap_page)
+       if (!list_empty(invalid_list)) {
+               kvm_mmu_commit_zap_page(vcpu->kvm, invalid_list);
                return;
+       }
 
        if (remote_flush)
                kvm_flush_remote_tlbs(vcpu->kvm);
@@ -4320,7 +4323,7 @@ static void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
        LIST_HEAD(invalid_list);
        u64 entry, gentry, *spte;
        int npte;
-       bool remote_flush, local_flush, zap_page;
+       bool remote_flush, local_flush;
        union kvm_mmu_page_role mask = { };
 
        mask.cr0_wp = 1;
@@ -4337,7 +4340,7 @@ static void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
        if (!ACCESS_ONCE(vcpu->kvm->arch.indirect_shadow_pages))
                return;
 
-       zap_page = remote_flush = local_flush = false;
+       remote_flush = local_flush = false;
 
        pgprintk("%s: gpa %llx bytes %d\n", __func__, gpa, bytes);
 
@@ -4357,8 +4360,7 @@ static void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
        for_each_gfn_indirect_valid_sp(vcpu->kvm, sp, gfn) {
                if (detect_write_misaligned(sp, gpa, bytes) ||
                      detect_write_flooding(sp)) {
-                       zap_page |= !!kvm_mmu_prepare_zap_page(vcpu->kvm, sp,
-                                                    &invalid_list);
+                       kvm_mmu_prepare_zap_page(vcpu->kvm, sp, &invalid_list);
                        ++vcpu->kvm->stat.mmu_flooded;
                        continue;
                }
@@ -4380,8 +4382,7 @@ static void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
                        ++spte;
                }
        }
-       mmu_pte_write_flush_tlb(vcpu, zap_page, remote_flush, local_flush);
-       kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list);
+       kvm_mmu_flush_or_zap(vcpu, &invalid_list, remote_flush, local_flush);
        kvm_mmu_audit(vcpu, AUDIT_POST_PTE_WRITE);
        spin_unlock(&vcpu->kvm->mmu_lock);
 }