Re: remove dma_virt_ops v2

santosh.shilimkar
2020-11-12T17:36:55Z

+ Ka-Cheong

On 11/12/20 5:23 AM, Jason Gunthorpe wrote:
> On Thu, Nov 12, 2020 at 10:40:30AM +0100, Christoph Hellwig wrote:
>> ping?
>>
>> 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
>
> Santosh can you please check the RDA parts??
>

Hi Ka-Cheong,

Can you please check Christoph change [1] which clean-up
dma-pool API to use ib_dma_* and slab allocator ? This was added
as part of your "net/rds: Use DMA memory pool allocation for rds_header"
commit.

Regards,
Santosh

[1] https://www.spinics.net/lists/linux-pci/msg101547.html