void kvm_arch_commit_memory_region(struct kvm *kvm,
				const struct kvm_userspace_memory_region *mem,
				const struct kvm_memory_slot *old,
				const struct kvm_memory_slot *new,
				enum kvm_mr_change change)
{
	int nr_mmu_pages = 0;

	if (!kvm->arch.n_requested_mmu_pages)
		nr_mmu_pages = kvm_mmu_calculate_mmu_pages(kvm);

	if (nr_mmu_pages)
		kvm_mmu_change_mmu_pages(kvm, nr_mmu_pages);

	/*
	 * Dirty logging tracks sptes in 4k granularity, meaning that large
	 * sptes have to be split.  If live migration is successful, the guest
	 * in the source machine will be destroyed and large sptes will be
	 * created in the destination. However, if the guest continues to run
	 * in the source machine (for example if live migration fails), small
	 * sptes will remain around and cause bad performance.
	 *
	 * Scan sptes if dirty logging has been stopped, dropping those
	 * which can be collapsed into a single large-page spte.  Later
	 * page faults will create the large-page sptes.
	 */
	if ((change != KVM_MR_DELETE) &&
		(old->flags & KVM_MEM_LOG_DIRTY_PAGES) &&
		!(new->flags & KVM_MEM_LOG_DIRTY_PAGES))
		kvm_mmu_zap_collapsible_sptes(kvm, new);

	/*
	 * Set up write protection and/or dirty logging for the new slot.
	 *
	 * For KVM_MR_DELETE and KVM_MR_MOVE, the shadow pages of old slot have
	 * been zapped so no dirty logging staff is needed for old slot. For
	 * KVM_MR_FLAGS_ONLY, the old slot is essentially the same one as the
	 * new and it's also covered when dealing with the new slot.
	 *
	 * FIXME: const-ify all uses of struct kvm_memory_slot.
	 */
	if (change != KVM_MR_DELETE)
		kvm_mmu_slot_apply_flags(kvm, (struct kvm_memory_slot *) new);
}

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