Re: remove dma_virt_ops v2

santosh.shilimkar
2020-11-17T19:11:29Z

On 11/17/20 2:50 AM, Ka-Cheong Poon wrote:
> On 11/13/20 1:36 AM, santosh.shilimkar@oracle.com wrote:
>> + 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.
>
>
> I applied the patch and ran some basic testing.  And it seems to
> work fine.
>
Thanks Ka-Cheong.

Jason, Feel free to add ack for the RDS part.

Regards,
Santosh