Re: [PATCH 2/4] nvmet-rdma: Use new SGL alloc/free helper for requests

Sagi Grimberg
2018-04-04T12:43:33Z

> @@ -565,24 +565,24 @@ static u16 nvmet_rdma_map_sgl_keyed(struct nvmet_rdma_rsp *rsp,
> {
> struct rdma_cm_id *cm_id = rsp->queue->cm_id;
> u64 addr = le64_to_cpu(sgl->addr);
> - u32 len = get_unaligned_le24(sgl->length);
> u32 key = get_unaligned_le32(sgl->key);
> int ret;
>
> + rsp->req.transfer_len = get_unaligned_le24(sgl->length);
> +

IIRC, this might result in nvmet-rdma executing data-transfer even
for failed requests in some error cases. I'm not sure this is the
only case, but have you tested what happens in error cases?

See nvmet_rdma_need_data_in()/nvmet_rdma_need_data_out() which look
at transfer_len.

> /* no data command? */
> - if (!len)
> + if (!rsp->req.transfer_len)
> return 0;
>
> - rsp->req.sg = sgl_alloc(len, GFP_KERNEL, &rsp->req.sg_cnt);
> - if (!rsp->req.sg)
> - return NVME_SC_INTERNAL;
> + ret = nvmet_req_alloc_sgl(&rsp->req, &rsp->queue->nvme_sq);
> + if (ret < 0)
> + goto error_out;
>
> ret = rdma_rw_ctx_init(&rsp->rw, cm_id->qp, cm_id->port_num,
> rsp->req.sg, rsp->req.sg_cnt, 0, addr, key,
> nvmet_data_dir(&rsp->req));
> if (ret < 0)
> - return NVME_SC_INTERNAL;
> - rsp->req.transfer_len += len;
> + goto error_out;
> rsp->n_rdma += ret;
>
> if (invalidate) {
> @@ -591,6 +591,10 @@ static u16 nvmet_rdma_map_sgl_keyed(struct nvmet_rdma_rsp *rsp,
> }
>
> return 0;
> +
> +error_out:
> + rsp->req.transfer_len = 0;
> + return NVME_SC_INTERNAL;
> }
>
> static u16 nvmet_rdma_map_sgl(struct nvmet_rdma_rsp *rsp)
>