Re: [PATCH 04/16] PCI/P2PDMA: Refactor pci_p2pdma_map_type() to take pagmap and device

On 5/3/21 3:57 PM, Jason Gunthorpe wrote:

On Mon, May 03, 2021 at 02:54:26PM -0700, John Hubbard wrote:

quoted

I guess my main concern here is that there are these pci*() functions
that somehow want to pass around struct device.

Well, this is the main issue - helpers being used inside IOMMU code
should not be called pci* functions. This is some generic device p2p
interface that happens to only support PCI to PCI transfers today.

Yes, maybe renaming a few levels of functions would help at least clarify
what the code can do. Once the code reaches layers that truly are
PCI-specific, that's where it should transition to using pci_dev args,
and that's also where it should return -ENOTSUPP back up the calling
stack.

thanks,
-- 
John Hubbard
NVIDIA