On Fri, Jul 25, 2025 at 10:30:46AM -0600, Logan Gunthorpe wrote:

On 2025-07-24 02:13, Leon Romanovsky wrote:

...

On Thu, Jul 24, 2025 at 10:03:13AM +0200, Christoph Hellwig wrote:

...

On Wed, Jul 23, 2025 at 04:00:06PM +0300, Leon Romanovsky wrote:

...

From: Leon Romanovsky leonro@nvidia.com

Export the pci_p2pdma_map_type() function to allow external modules and subsystems to determine the appropriate mapping type for P2PDMA transfers between a provider and target device.

External modules have no business doing this.

VFIO PCI code is built as module. There is no way to access PCI p2p code without exporting functions in it.

The solution that would make more sense to me would be for either dma_iova_try_alloc() or another helper in dma-iommu.c to handle the P2PDMA case.

This has nothing to do with dma-iommu.c, the decisions here still need to be made even if dma-iommu.c is not compiled in.

It could be exported from the main dma code, but I think it would just be a 1 line wrapper around the existing function? I'd rather rename the functions and leave them in the p2pdma.c files...

Jason