RE: [PATCH v22 4/4] scsi: ufs: Add HPB 2.0 support

[Avri Altman <Avri.Altman@wdc.com>]

> @@ -2656,7 +2656,12 @@ static int ufshcd_queuecommand(struct Scsi_Host
> *host, struct scsi_cmnd *cmd)
> 
>         lrbp->req_abort_skip = false;
> 
> -       ufshpb_prep(hba, lrbp);
> +       err = ufshpb_prep(hba, lrbp);
> +       if (err == -EAGAIN) {
> +               lrbp->cmd = NULL;
> +               ufshcd_release(hba);
> +               goto out;
> +       }
Did I miss-read it, or are you bailing out of wb failed e.g. because no tag is available?
Why not continue with read10?



> +       if (blk_insert_cloned_request(q, req) != BLK_STS_OK)
> +               return -EAGAIN;
Why did you choose to use blk_insert_cloned_request and not e.g. the more common blk_execute_rq_nowait?

> +       hpb->stats.pre_req_cnt++;
> +
> +       return 0;
> +}

> -       ufshpb_set_hpb_read_to_upiu(hpb, lrbp, lpn, ppn, transfer_len);
> +       if (ufshpb_is_required_wb(hpb, transfer_len)) {
> +               err = ufshpb_issue_pre_req(hpb, cmd, &read_id);
> +               if (err) {
> +                       unsigned long timeout;
> +
> +                       timeout = cmd->jiffies_at_alloc + msecs_to_jiffies(
> +                                 hpb->params.requeue_timeout_ms);
> +                       if (time_before(jiffies, timeout))
> +                               return -EAGAIN;
Why requeue_timeout_ms needs to be a configurable parameter?
Why rq->timeout is not enough?

Thanks,
Avri