KVM: Separate rmap_pde from kvm_lpage_info->write_count

This makes it possible to loop over rmap_pde arrays in the same way as
we do over rmap so that we can optimize kvm_handle_hva_range() easily in
the following patch.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index d2855f8..3b3f5ae 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -960,13 +960,13 @@
 static unsigned long *__gfn_to_rmap(gfn_t gfn, int level,
 				    struct kvm_memory_slot *slot)
 {
-	struct kvm_lpage_info *linfo;
+	unsigned long idx;
 
 	if (likely(level == PT_PAGE_TABLE_LEVEL))
 		return &slot->rmap[gfn - slot->base_gfn];
 
-	linfo = lpage_info_slot(gfn, slot, level);
-	return &linfo->rmap_pde;
+	idx = gfn_to_index(gfn, slot->base_gfn, level);
+	return &slot->arch.rmap_pde[level - PT_DIRECTORY_LEVEL][idx];
 }
 
 /*