# Re: \[PATCH V3 09/13\] DMA: Add dma\_map\_decrypted/dma\_unmap\_encrypted() function

- From: Tianyu Lan \<hidden\>
- Date: 2021-08-12 15:38:46 
- List: linux-hyperv
- Page: https://ratatoskr.run/linux-hyperv/2021/08/1476228
- Thread: https://ratatoskr.run/xen-devel/2021/08/1472230/t.md

```text


On 8/12/2021 8:26 PM, Christoph Hellwig wrote:
> On Mon, Aug 09, 2021 at 01:56:13PM -0400, Tianyu Lan wrote:
>> From: Tianyu Lan <redacted>
>>
>> In Hyper-V Isolation VM with AMD SEV, swiotlb boucne buffer
>> needs to be mapped into address space above vTOM and so
>> introduce dma_map_decrypted/dma_unmap_encrypted() to map/unmap
>> bounce buffer memory. The platform can populate man/unmap callback
>> in the dma memory decrypted ops.
>
> Nothing here looks actually DMA related, and the names are horribly
> confusing vs the actual dma_map_* calls.
>

OK. So this still need to keep in the set_memory.c file.
```