KVM: MMU: cleanup page alloc and free

Using __get_free_page instead of alloc_page and page_address,
using free_page instead of __free_page and virt_to_page
Signed-off-by: NXiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

arch/x86/kvm/mmu.c

@@ -379,15 +379,15 @@ static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc,
 static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache *cache,
 				       int min)
 {
-	struct page *page;
+	void *page;
 
 	if (cache->nobjs >= min)
 		return 0;
 	while (cache->nobjs < ARRAY_SIZE(cache->objects)) {
-		page = alloc_page(GFP_KERNEL);
+		page = (void *)__get_free_page(GFP_KERNEL);
 		if (!page)
 			return -ENOMEM;
-		cache->objects[cache->nobjs++] = page_address(page);
+		cache->objects[cache->nobjs++] = page;
 	}
 	return 0;
 }
@@ -1032,9 +1032,9 @@ static void kvm_mmu_free_page(struct kvm *kvm, struct kvm_mmu_page *sp)
 	ASSERT(is_empty_shadow_page(sp->spt));
 	hlist_del(&sp->hash_link);
 	list_del(&sp->link);
-	__free_page(virt_to_page(sp->spt));
+	free_page((unsigned long)sp->spt);
 	if (!sp->role.direct)
-		__free_page(virt_to_page(sp->gfns));
+		free_page((unsigned long)sp->gfns);
 	kmem_cache_free(mmu_page_header_cache, sp);
 	kvm_mod_used_mmu_pages(kvm, -1);
 }