Re: [PATCH v8 00/23] dma-mapping: Track shared DMA state through direct, pool and swiotlb paths

From: Leon Romanovsky

Date: Tue Jul 21 2026 - 08:45:12 EST


On Fri, Jul 17, 2026 at 11:34:18PM +0530, Aneesh Kumar K.V (Arm) wrote:
> This series tracks confidential-computing shared DMA state through the
> dma-direct, dma-pool, and swiotlb paths so that encrypted and decrypted
> DMA buffers are handled consistently.

<...>

> - makes dma_direct_map_phys() choose the DMA address encoding from
> DMA_ATTR_CC_SHARED and fall back to swiotlb when a shared DMA request
> cannot use the direct mapping, which lets arm64 and x86 CCA guests stop
> relying on SWIOTLB_FORCE for DMA mappings

Why don't we continue the effort to remove "struct page" entirely
from the DMA API internals?

IMHO, everything not exposed to DMA API users should use
phys_addr_t, including the DMA address pool.

Thanks