Re: [PATCH 06/12] IB/core: Add optional PCI P2P flag to rdma_rw_ctx_[init|destroy]()

Logan Gunthorpe
2018-01-08T19:06:13Z

On 08/01/18 11:57 AM, Christoph Hellwig wrote:
> It does, sort of - but in a different way then the normal DMA map
> ops. And only to work around the fact that we need to map our
> P2P space into struct pages. Without that we could just pass the
> bus address around, but the Linux stack and VM isn't anywhere near
> ready for something that advanced.

Yeah, wouldn't that be nice.

Ok, so if we shouldn't touch the dma_map infrastructure how should the
workaround to opt-out HFI and QIB look? I'm not that familiar with the
RDMA code.

Thanks,

Logan