Re: [PATCH RFC v1 5/6] xen-swiotlb: convert variables to arrays

Christoph Hellwig
2021-02-04T08:41:13Z

So one thing that has been on my mind for a while: I'd really like
to kill the separate dma ops in Xen swiotlb. If we compare xen-swiotlb
to swiotlb the main difference seems to be:

- additional reasons to bounce I/O vs the plain DMA capable
- the possibility to do a hypercall on arm/arm64
- an extra translation layer before doing the phys_to_dma and vice
versa
- an special memory allocator

I wonder if inbetween a few jump labels or other no overhead enablement
options and possibly better use of the dma_range_map we could kill
off most of swiotlb-xen instead of maintaining all this code duplication?