Re: [PATCHv2 1/1] RDMA/irdma: Add support for dmabuf pin memory regions

[Yanjun Zhu <yanjun.zhu@linux.dev>]

在 2023/1/4 8:21, Saleem, Shiraz 写道:
>> Subject: RE: [PATCHv2 1/1] RDMA/irdma: Add support for dmabuf pin memory
>> regions
>>
> [......]
>
>>> +
>>> +	switch (req.reg_type) {
>>> +	case IRDMA_MEMREG_TYPE_QP:
>>> +		total = req.sq_pages + req.rq_pages + shadow_pgcnt;
>>> +		if (total > iwmr->page_cnt) {
>>> +			err = -EINVAL;
>>> +			goto error;
>>> +		}
>>> +		total = req.sq_pages + req.rq_pages;
>>> +		use_pbles = (total > 2);
>>> +		err = irdma_handle_q_mem(iwdev, &req, iwpbl, use_pbles);
>>> +		if (err)
>>> +			goto error;
>>> +
>>> +		ucontext = rdma_udata_to_drv_context(udata, struct
>>> irdma_ucontext,
>>> +						     ibucontext);
>>> +		spin_lock_irqsave(&ucontext->qp_reg_mem_list_lock, flags);
>>> +		list_add_tail(&iwpbl->list, &ucontext->qp_reg_mem_list);
>>> +		iwpbl->on_list = true;
>>> +		spin_unlock_irqrestore(&ucontext->qp_reg_mem_list_lock, flags);
>>> +		break;
>>> +	case IRDMA_MEMREG_TYPE_CQ:
>>> +		if (iwdev->rf->sc_dev.hw_attrs.uk_attrs.feature_flags &
>>> IRDMA_FEATURE_CQ_RESIZE)
>>> +			shadow_pgcnt = 0;
>>> +		total = req.cq_pages + shadow_pgcnt;
>>> +		if (total > iwmr->page_cnt) {
>>> +			err = -EINVAL;
>>> +			goto error;
>>> +		}
>>> +
>>> +		use_pbles = (req.cq_pages > 1);
>>> +		err = irdma_handle_q_mem(iwdev, &req, iwpbl, use_pbles);
>>> +		if (err)
>>> +			goto error;
>>> +
>>> +		ucontext = rdma_udata_to_drv_context(udata, struct
>>> irdma_ucontext,
>>> +						     ibucontext);
>>> +		spin_lock_irqsave(&ucontext->cq_reg_mem_list_lock, flags);
>>> +		list_add_tail(&iwpbl->list, &ucontext->cq_reg_mem_list);
>>> +		iwpbl->on_list = true;
>>> +		spin_unlock_irqrestore(&ucontext->cq_reg_mem_list_lock, flags);
>>> +		break;
>> I don't think we want to do this for user QP, CQ pinned memory. In fact, it will just
>> be dead-code.
>>
>> The irdma provider implementation of the ibv_reg_dmabuf_mr will just default to
>> IRDMA_MEMREG_TYPE_MEM type similar to how irdma_ureg_mr is implemented.
>>
>> https://github.com/linux-rdma/rdma-
>> core/blob/master/providers/irdma/uverbs.c#L128
>>
>> It should simplify this function a lot.
>>
>>
> Actually I don't see a need even to use the irdma_mem_reg_req ABI struct to pass any info from user-space like reg_type.

In the latest commit, the irdma_mem_reg_req ABI struct is removed.

I will send out it very soon.

Zhu Yanjun

>
> Shiraz
>