[RFT][PATCH v2 0/9] Update vfio_pin/unpin_pages API

[Tian, Kevin]

> From: Nicolin Chen
> Sent: Wednesday, July 6, 2022 2:28 PM
> 
> This is a preparatory series for IOMMUFD v2 patches. It prepares for
> replacing vfio_iommu_type1 implementations of vfio_pin/unpin_pages()
> with IOMMUFD version.
> 
> There's a gap between these two versions: the vfio_iommu_type1 version
> inputs a non-contiguous PFN list and outputs another PFN list for the
> pinned physical page list, while the IOMMUFD version only supports a
> contiguous address input by accepting the starting IO virtual address
> of a set of pages to pin and by outputting to a physical page list.
> 
> The nature of existing callers mostly aligns with the IOMMUFD version,
> except s390's vfio_ccw_cp code where some additional change is needed
> along with this series. Overall, updating to "iova" and "phys_page"
> does improve the caller side to some extent.
> 
> Also fix a misuse of physical address and virtual address in the s390's
> crypto code. And update the input naming at the adjacent vfio_dma_rw().
> 
> This is on github:
> https://github.com/nicolinc/iommufd/commits/vfio_pin_pages
> 
> Request for testing: I only did build for s390 and i915 code, so it'd
> be nice to have people who have environment to run sanity accordingly.
> 

+Terrence who is testing it for i915 now...