KVM: x86: pass struct kvm_mmu_page to account/unaccount_shadowed

Prepare for multiple address spaces this way, since a VCPU is not available
where unaccount_shadowed is called.  We will get to the right kvm_memslots
struct through the role field in struct kvm_mmu_page.
Reviewed-by: NTakuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Reviewed-by: NRadim Krcmar <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/mmu.c

@@ -804,12 +804,14 @@ static struct kvm_lpage_info *lpage_info_slot(gfn_t gfn,
 	return &slot->arch.lpage_info[level - 2][idx];
 }
 
-static void account_shadowed(struct kvm *kvm, gfn_t gfn)
+static void account_shadowed(struct kvm *kvm, struct kvm_mmu_page *sp)
 {
 	struct kvm_memory_slot *slot;
 	struct kvm_lpage_info *linfo;
+	gfn_t gfn;
 	int i;
 
+	gfn = sp->gfn;
 	slot = gfn_to_memslot(kvm, gfn);
 	for (i = PT_DIRECTORY_LEVEL; i <= PT_MAX_HUGEPAGE_LEVEL; ++i) {
 		linfo = lpage_info_slot(gfn, slot, i);
@@ -818,12 +820,14 @@ static void account_shadowed(struct kvm *kvm, gfn_t gfn)
 	kvm->arch.indirect_shadow_pages++;
 }
 
-static void unaccount_shadowed(struct kvm *kvm, gfn_t gfn)
+static void unaccount_shadowed(struct kvm *kvm, struct kvm_mmu_page *sp)
 {
 	struct kvm_memory_slot *slot;
 	struct kvm_lpage_info *linfo;
+	gfn_t gfn;
 	int i;
 
+	gfn = sp->gfn;
 	slot = gfn_to_memslot(kvm, gfn);
 	for (i = PT_DIRECTORY_LEVEL; i <= PT_MAX_HUGEPAGE_LEVEL; ++i) {
 		linfo = lpage_info_slot(gfn, slot, i);
@@ -2131,7 +2135,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
 		if (level > PT_PAGE_TABLE_LEVEL && need_sync)
 			kvm_sync_pages(vcpu, gfn);
 
-		account_shadowed(vcpu->kvm, gfn);
+		account_shadowed(vcpu->kvm, sp);
 	}
 	sp->mmu_valid_gen = vcpu->kvm->arch.mmu_valid_gen;
 	init_shadow_page_table(sp);
@@ -2312,7 +2316,7 @@ static int kvm_mmu_prepare_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp,
 	kvm_mmu_unlink_parents(kvm, sp);
 
 	if (!sp->role.invalid && !sp->role.direct)
-		unaccount_shadowed(kvm, sp->gfn);
+		unaccount_shadowed(kvm, sp);
 
 	if (sp->unsync)
 		kvm_unlink_unsync_page(kvm, sp);