Re: [PATCH for-next v2 0/3] RDMA: Support CQs with user memory

[Jason Gunthorpe <jgg@nvidia.com>]

On Tue, Jul 08, 2025 at 08:23:05PM +0000, Michael Margolin wrote:
> This series is adding a common way for creating CQs on top of
> preallocated memory supplied by userspace. The memory buffer can be
> provided as a virtual address or by dmabuf, in both cases a umem object
> is created for driver's use.
> EFA is the first to support this new interface, new drivers or existing
> drivers that want/need to get the memory from userspace are expected to
> use this flow.
> 
> It's follow-up of the discussion in [1].
> 
> Changelog
> =========
> Changes from v1 [2]:
> - Added a new "create_cq_umem" driver op instead of a flag set by
>   supporting drivers
> - Added ib_umem_is_contiguous() and ib_umem_start_dma_addr() helpers in
>   a new patch
> - Dropped references to umem scatter-gather list in EFA implementation
>   and using the new helpers that hide the details instead
> 
> References
> ==========
> [1] https://lore.kernel.org/all/c7d312ac-19a0-45e3-9f40-3e6f81500f83@amazon.com/
> [2] https://lore.kernel.org/all/20250701231545.14282-1-mrgolin@amazon.com/
> 
> Thanks
> 
> Michael Margolin (3):
>   RDMA/uverbs: Add a common way to create CQ with umem
>   RDMA/core: Add umem "is_contiguous" and "start_dma_addr" helpers
>   RDMA/efa: Add CQ with external memory support

It looks Ok to me

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>

Jason