Re: [PATCH v5 7/7] KVM: guest_memfd: Rework PREPARE config and hook into a more generic CONVERT

[Xiaoyao Li]

On 7/15/2026 7:10 AM, Sean Christopherson wrote:
> Rework guest_memfd's "prepare" hook into a more generic "convert" flow in
> anticipation of supporting in-place conversion, at which point KVM will use
> the hook for both to-private and to-shared conversions, not just to
> "prepare" PRIVATE memory.
>
> Opportunistically rename kvm_gmem_prepare_folio() to kvm_gmem_make_private()
> to better reflect its role.

[...]

> @@ -90,8 +90,8 @@ static int kvm_gmem_prepare_folio(struct kvm *kvm, struct kvm_memory_slot *slot,
>   	gfn = ALIGN_DOWN(gfn, nr_pages);
>   	index = kvm_gmem_get_index(slot, gfn);
>   
> -	return kvm_arch_gmem_prepare(kvm, gfn, folio_file_pfn(folio, index),
> -				     nr_pages, folio_order(folio));
> +	return kvm_arch_gmem_convert(kvm, gfn, folio_file_pfn(folio, index),
> +				     nr_pages, folio_order(folio), true);
>   #else
>   	return 0;
>   #endif
> @@ -798,7 +798,7 @@ int kvm_gmem_get_pfn(struct kvm *kvm, struct kvm_memory_slot *slot,
>   		folio_mark_uptodate(folio);
>   	}
>   
> -	r = kvm_gmem_prepare_folio(kvm, slot, gfn, folio);
> +	r = kvm_gmem_make_private(kvm, slot, gfn, folio);

I think this and above renaming don't make sense, because 
kvm_gmem_get_pfn() can be invoked for shared memory for non-Coco VMs 
when KVM_MEMSLOT_GMEM_ONLY is set.

Maybe this patch can be moved to gmem in-place series and after [1]?

[1] 
https://lore.kernel.org/all/3b64e897-93a8-4f9c-88a9-f416ff44b09d@xxxxxxxxx/

>   	folio_unlock(folio);
>