From: Matthew Wilcox <willy@xxxxxxxxxxxxx> Sent: Thursday, April 18, 2024 7:29 AM > > 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. Good point. I'll update sizes throughout to use the correct terminology. Michael > > You've written a lot here, and I'm not an expert on swiommu, but nothing > else leapt out at me.
