Re: [PATCH v1 00/14] vfio: Device memory DMA mapping improvements

[Jason Gunthorpe]

On Mon, Mar 08, 2021 at 02:47:16PM -0700, Alex Williamson wrote:
> The primary goal of this series is to better manage device memory
> mappings, both with a much simplified scheme to zap CPU mappings of
> device memory using unmap_mapping_range() and also to restrict IOMMU
> mappings of PFNMAPs to vfio device memory and drop those mappings on
> device release.  This series updates vfio-pci to include the necessary
> vma-to-pfn interface, allowing the type1 IOMMU backend to recognize
> vfio device memory.  If other bus drivers support peer-to-peer DMA,
> they should be updated with a similar callback and trigger the device
> notifier on release.

I only skimmed it for now, but it looks pretty good

I need to sit down and take a very careful look at all of this, my
rdma address_space patch included..

Jason