Re: remove dma_virt_ops v2

Jason Gunthorpe
2020-11-17T19:42:11Z

On Fri, Nov 06, 2020 at 07:19:31PM +0100, Christoph Hellwig wrote:
> Hi Jason,
>
> this series switches the RDMA core to opencode the special case of
> devices bypassing the DMA mapping in the RDMA ULPs. The virt ops
> have caused a bit of trouble due to the P2P code node working with
> them due to the fact that we'd do two dma mapping iterations for a
> single I/O, but also are a bit of layering violation and lead to
> more code than necessary.
>
> Tested with nvme-rdma over rxe.
>
> Note that the rds changes are untested, as I could not find any
> simple rds test setup.
>
> Changes since v2:
> - simplify the INFINIBAND_VIRT_DMA dependencies
> - add a ib_uses_virt_dma helper
> - use ib_uses_virt_dma in nvmet-rdma to disable p2p for virt_dma devices
> - use ib_dma_max_seg_size in umem
> - stop using dmapool in rds
>
> Changes since v1:
> - disable software RDMA drivers for highmem configs
> - update the PCI commit logs

All applied to for-next, thanks everyone

Jason