Re: [PATCH] qla2xxx: Do not consume srb greedily

[Himanshu Madhani]

> On Sep 29, 2020, at 2:38 AM, Daniel Wagner <dwagner@xxxxxxx> wrote:
> 
> qla2xx_process_get_sp_from_handle() will clear the slot which the
> current srb is stored. So this function has a side effect. Therefore,
> we can't use it in qla24xx_process_mbx_iocb_response() to check
> for consistency and later again in qla24xx_mbx_iocb_entry().
> 
> Let's move the consistency check directly into
> qla24xx_mbx_iocb_entry() and avoid the double call or any open coding
> of the qla2xx_process_get_sp_from_handle() functionality.
> 
> Fixes: 31a3271ff11b ("scsi: qla2xxx: Handle incorrect entry_type entries")
> Signed-off-by: Daniel Wagner <dwagner@xxxxxxx>
> ---
> Hi,
> 
> Brown bag for me please. My test patch had an open coded version of
> qla2xx_process_get_sp_from_handle() which didn't consume the srb. When
> I prepared it for sending it out, I 'cleaned' it up by using
> qla2xx_process_get_sp_from_handle() twice.
> 
> Sorry,
> Daniel
> 
> drivers/scsi/qla2xxx/qla_isr.c | 42 +++++++++++++++---------------------------
> 1 file changed, 15 insertions(+), 27 deletions(-)
> 
> diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c
> index 96811354f78a..2baba87c4e0c 100644
> --- a/drivers/scsi/qla2xxx/qla_isr.c
> +++ b/drivers/scsi/qla2xxx/qla_isr.c
> @@ -1839,6 +1839,7 @@ qla24xx_mbx_iocb_entry(scsi_qla_host_t *vha, struct req_que *req,
>     struct mbx_24xx_entry *pkt)
> {
> 	const char func[] = "MBX-IOCB2";
> +	struct qla_hw_data *ha = vha->hw;
> 	srb_t *sp;
> 	struct srb_iocb *si;
> 	u16 sz, i;
> @@ -1848,6 +1849,18 @@ qla24xx_mbx_iocb_entry(scsi_qla_host_t *vha, struct req_que *req,
> 	if (!sp)
> 		return;
> 
> +	if (sp->type == SRB_SCSI_CMD ||
> +	    sp->type == SRB_NVME_CMD ||
> +	    sp->type == SRB_TM_CMD) {
> +		ql_log(ql_log_warn, vha, 0x509d,
> +			"Inconsistent event entry type %d\n", sp->type);
> +		if (IS_P3P_TYPE(ha))
> +			set_bit(FCOE_CTX_RESET_NEEDED, &vha->dpc_flags);
> +		else
> +			set_bit(ISP_ABORT_NEEDED, &vha->dpc_flags);
> +		return;
> +	}
> +
> 	si = &sp->u.iocb_cmd;
> 	sz = min(ARRAY_SIZE(pkt->mb), ARRAY_SIZE(sp->u.iocb_cmd.u.mbx.in_mb));
> 
> @@ -3406,32 +3419,6 @@ void qla24xx_nvme_ls4_iocb(struct scsi_qla_host *vha,
> 	sp->done(sp, comp_status);
> }
> 
> -static void qla24xx_process_mbx_iocb_response(struct scsi_qla_host *vha,
> -	struct rsp_que *rsp, struct sts_entry_24xx *pkt)
> -{
> -	struct qla_hw_data *ha = vha->hw;
> -	srb_t *sp;
> -	static const char func[] = "MBX-IOCB2";
> -
> -	sp = qla2x00_get_sp_from_handle(vha, func, rsp->req, pkt);
> -	if (!sp)
> -		return;
> -
> -	if (sp->type == SRB_SCSI_CMD ||
> -	    sp->type == SRB_NVME_CMD ||
> -	    sp->type == SRB_TM_CMD) {
> -		ql_log(ql_log_warn, vha, 0x509d,
> -			"Inconsistent event entry type %d\n", sp->type);
> -		if (IS_P3P_TYPE(ha))
> -			set_bit(FCOE_CTX_RESET_NEEDED, &vha->dpc_flags);
> -		else
> -			set_bit(ISP_ABORT_NEEDED, &vha->dpc_flags);
> -		return;
> -	}
> -
> -	qla24xx_mbx_iocb_entry(vha, rsp->req, (struct mbx_24xx_entry *)pkt);
> -}
> -
> /**
>  * qla24xx_process_response_queue() - Process response queue entries.
>  * @vha: SCSI driver HA context
> @@ -3539,7 +3526,8 @@ void qla24xx_process_response_queue(struct scsi_qla_host *vha,
> 			    (struct abort_entry_24xx *)pkt);
> 			break;
> 		case MBX_IOCB_TYPE:
> -			qla24xx_process_mbx_iocb_response(vha, rsp, pkt);
> +			qla24xx_mbx_iocb_entry(vha, rsp->req,
> +			    (struct mbx_24xx_entry *)pkt);
> 			break;
> 		case VP_CTRL_IOCB_TYPE:
> 			qla_ctrlvp_completed(vha, rsp->req,
> -- 
> 2.16.4
> 

Makes sense :)  

Reviewed-by: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx>
--
Himanshu Madhani	 Oracle Linux Engineering