KVM: kvm_is_visible_gfn can be boolean

This patch makes kvm_is_visible_gfn return bool due to this particular
function only using either one or zero as its return value.

No functional change.

Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

include/linux/kvm_host.h

@@ -641,7 +641,7 @@ int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len);
 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len);
 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn);
-int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn);
+bool kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn);
 unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn);
 void mark_page_dirty(struct kvm *kvm, gfn_t gfn);
 

virt/kvm/kvm_main.c

@@ -1164,15 +1164,15 @@ struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn
 	return __gfn_to_memslot(kvm_vcpu_memslots(vcpu), gfn);
 }
 
-int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
+bool kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
 {
 	struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
 
 	if (!memslot || memslot->id >= KVM_USER_MEM_SLOTS ||
 	      memslot->flags & KVM_MEMSLOT_INVALID)
-		return 0;
+		return false;
 
-	return 1;
+	return true;
 }
 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);