Commit bcdd9a93 authored by Xiao Guangrong's avatar Xiao Guangrong Committed by Avi Kivity
Browse files

KVM: MMU: cleanup for dropping parent pte 



Introduce drop_parent_pte to remove the rmap of parent pte and
clear parent pte

Signed-off-by: default avatarXiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
parent 38e3b2b2

arch/x86/kvm/mmu.c

+12 −9
Original line number Diff line number Diff line
@@ -1084,6 +1084,13 @@ static void mmu_page_remove_parent_pte(struct kvm_mmu_page *sp, 
	pte_list_remove(parent_pte, &sp->parent_ptes);

}



static void drop_parent_pte(struct kvm_mmu_page *sp,

			    u64 *parent_pte)

{

	mmu_page_remove_parent_pte(sp, parent_pte);

	__set_spte(parent_pte, shadow_trap_nonpresent_pte);

}



static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu,

					       u64 *parent_pte, int direct)

{
@@ -1560,8 +1567,7 @@ static void validate_direct_spte(struct kvm_vcpu *vcpu, u64 *sptep, 
		if (child->role.access == direct_access)

			return;



		mmu_page_remove_parent_pte(child, sptep);

		__set_spte(sptep, shadow_trap_nonpresent_pte);

		drop_parent_pte(child, sptep);

		kvm_flush_remote_tlbs(vcpu->kvm);

	}

}
@@ -1578,7 +1584,7 @@ static void mmu_page_zap_pte(struct kvm *kvm, struct kvm_mmu_page *sp, 
			drop_spte(kvm, spte, shadow_trap_nonpresent_pte);

		else {

			child = page_header(pte & PT64_BASE_ADDR_MASK);

			mmu_page_remove_parent_pte(child, spte);

			drop_parent_pte(child, spte);

		}

	}

	__set_spte(spte, shadow_trap_nonpresent_pte);
@@ -1613,10 +1619,8 @@ static void kvm_mmu_unlink_parents(struct kvm *kvm, struct kvm_mmu_page *sp) 
{

	u64 *parent_pte;



	while ((parent_pte = pte_list_next(&sp->parent_ptes, NULL))) {

		kvm_mmu_put_page(sp, parent_pte);

		__set_spte(parent_pte, shadow_trap_nonpresent_pte);

	}

	while ((parent_pte = pte_list_next(&sp->parent_ptes, NULL)))

		drop_parent_pte(sp, parent_pte);

}



static int mmu_zap_unsync_children(struct kvm *kvm,
@@ -2046,8 +2050,7 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, 
			u64 pte = *sptep;



			child = page_header(pte & PT64_BASE_ADDR_MASK);

			mmu_page_remove_parent_pte(child, sptep);

			__set_spte(sptep, shadow_trap_nonpresent_pte);

			drop_parent_pte(child, sptep);

			kvm_flush_remote_tlbs(vcpu->kvm);

		} else if (pfn != spte_to_pfn(*sptep)) {

			pgprintk("hfn old %llx new %llx\n",