Re: [PATCH 1/1] Documentation/core-api: Add swiotlb documentation

[Matthew Wilcox]

On Thu, Apr 18, 2024 at 06:52:13AM -0700, mhkelley58@xxxxxxxxx wrote:
> There's currently no documentation for the swiotlb. Add documentation
> describing usage scenarios, the key APIs, and implementation details.
> Group the new documentation with other DMA-related documentation.

This is really well written.  Thank you.  One minor nit below.

> +Usage Scenarios
> +---------------
> +The swiotlb was originally created to handle DMA for devices
> +with addressing limitations. As physical memory sizes grew
> +beyond 4 Gbytes, some devices could only provide 32-bit DMA
> +addresses. By allocating bounce buffer memory below the 4 Gbyte

I'd prefer GiB to Gbytes; we might also prefer GB, Gigabyte or Gibibyte,
but Gbytes seems wrong.

You've written a lot here, and I'm not an expert on swiommu, but nothing
else leapt out at me.