addr_to_page
struct radix_tree_root addr_to_page;
vsie_page = radix_tree_lookup(&kvm->arch.vsie.addr_to_page, addr >> 9);
radix_tree_delete(&kvm->arch.vsie.addr_to_page,
if (radix_tree_insert(&kvm->arch.vsie.addr_to_page, addr >> 9, vsie_page)) {
INIT_RADIX_TREE(&kvm->arch.vsie.addr_to_page, GFP_KERNEL_ACCOUNT);
radix_tree_delete(&kvm->arch.vsie.addr_to_page,
struct page *page = addr_to_page(addr);