Re: [PATCH rdma-next 18/50] RDMA/erdma: Separate user and kernel CQ creation paths

[Cheng Xu <chengyou@linux.alibaba.com>]

On 2/13/26 6:57 PM, Leon Romanovsky wrote:
> From: Leon Romanovsky <leonro@nvidia.com>
> 
> Split CQ creation into distinct kernel and user flows. The erdma driver,
> inherited from mlx4, uses a problematic pattern that shares and caches
> umem in erdma_map_user_dbrecords(). This design blocks the driver from
> supporting generic umem sources (VMA, dmabuf, memfd, and others).
> 
> Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
> ---
>  drivers/infiniband/hw/erdma/erdma_main.c  |  1 +
>  drivers/infiniband/hw/erdma/erdma_verbs.c | 97 ++++++++++++++++++++-----------
>  drivers/infiniband/hw/erdma/erdma_verbs.h |  2 +
>  3 files changed, 67 insertions(+), 33 deletions(-)
> 
> diff --git a/drivers/infiniband/hw/erdma/erdma_main.c b/drivers/infiniband/hw/erdma/erdma_main.c
> index f35b30235018..1b6426e89d80 100644
> --- a/drivers/infiniband/hw/erdma/erdma_main.c
> +++ b/drivers/infiniband/hw/erdma/erdma_main.c
> @@ -505,6 +505,7 @@ static const struct ib_device_ops erdma_device_ops = {
>  	.alloc_pd = erdma_alloc_pd,
>  	.alloc_ucontext = erdma_alloc_ucontext,
>  	.create_cq = erdma_create_cq,
> +	.create_user_cq = erdma_create_user_cq,
>  	.create_qp = erdma_create_qp,
>  	.dealloc_pd = erdma_dealloc_pd,
>  	.dealloc_ucontext = erdma_dealloc_ucontext,

<...>

> +
> +int erdma_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
> +		    struct uverbs_attr_bundle *attrs)

create_cq will be used for kernel CQ creation, and the third input parameter
'struct uverbs_attr_bundle *attrs' will be useless, so it can be removed? Same to
all drivers.


> +{

<...>

> +	ret = create_cq_cmd(NULL, cq);
> +	if (ret)
> +		goto err_free_res;


In create_cq_cmd, should add the following change:

diff --git a/drivers/infiniband/hw/erdma/erdma_verbs.c b/drivers/infiniband/hw/erdma/erdma_verbs.c
index 8c30df61ae3d..eca28524e04b 100644
--- a/drivers/infiniband/hw/erdma/erdma_verbs.c
+++ b/drivers/infiniband/hw/erdma/erdma_verbs.c
@@ -240,7 +240,7 @@ static int create_cq_cmd(struct erdma_ucontext *uctx, struct erdma_cq *cq)
                req.first_page_offset = mem->page_offset;
                req.cq_dbrec_dma = cq->user_cq.dbrec_dma;
 
-               if (uctx->ext_db.enable) {
+               if (uctx && uctx->ext_db.enable) {
                        req.cfg1 |= FIELD_PREP(
                                ERDMA_CMD_CREATE_CQ_MTT_DB_CFG_MASK, 1);
                        req.cfg2 = FIELD_PREP(ERDMA_CMD_CREATE_CQ_DB_CFG_MASK,


Thanks,
Cheng Xu