[PATCH] qla2xxx: Return EBUSY on fcport deletion

[PATCH] qla2xxx: Return EBUSY on fcport deletion

[Daniel Wagner]

When the fcport is about to be deleted we should return EBUSY instead
of ENODEV. Only for EBUSY the request will be requeued in a multipath
setup.

Also in case we have a valid qpair but the firmware has not yet
started return EBUSY to avoid dropping the request.

Signed-off-by: Daniel Wagner <dwagner@suse.de>
---
Hi,

During port bounce and fail tests we observed that requests get
dropped on a failing path because the driver returned ENODEV and thus
the multipath code didn't requeue the request.

The tests were done with only the 'fcport && fcport->deleted' condition
but Hannes suggested we might as well do the same for 'qpair &&
!qpair->fw_started'.

Thanks,
Daniel

 drivers/scsi/qla2xxx/qla_nvme.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/qla2xxx/qla_nvme.c b/drivers/scsi/qla2xxx/qla_nvme.c
index 5cc1bbb1ed74..db8b802b147c 100644
--- a/drivers/scsi/qla2xxx/qla_nvme.c
+++ b/drivers/scsi/qla2xxx/qla_nvme.c
@@ -555,8 +555,11 @@ static int qla_nvme_post_cmd(struct nvme_fc_local_port *lport,
 
 	fcport = qla_rport->fcport;
 
-	if (!qpair || !fcport || (qpair && !qpair->fw_started) ||
+	if ((qpair && !qpair->fw_started) ||
 	    (fcport && fcport->deleted))
+		return -EBUSY;
+
+	if (!qpair || !fcport)
 		return rval;
 
 	vha = fcport->vha;
-- 
2.16.4

Re: [PATCH] qla2xxx: Return EBUSY on fcport deletion

[Arun Easi]

On Mon, 12 Oct 2020, 2:11am, Daniel Wagner wrote:

> When the fcport is about to be deleted we should return EBUSY instead
> of ENODEV. Only for EBUSY the request will be requeued in a multipath
> setup.
> 
> Also in case we have a valid qpair but the firmware has not yet
> started return EBUSY to avoid dropping the request.
> 
> Signed-off-by: Daniel Wagner <dwagner@suse.de>
> ---
> Hi,
> 
> During port bounce and fail tests we observed that requests get
> dropped on a failing path because the driver returned ENODEV and thus
> the multipath code didn't requeue the request.
> 
> The tests were done with only the 'fcport && fcport->deleted' condition
> but Hannes suggested we might as well do the same for 'qpair &&
> !qpair->fw_started'.
> 
> Thanks,
> Daniel
> 
>  drivers/scsi/qla2xxx/qla_nvme.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/scsi/qla2xxx/qla_nvme.c b/drivers/scsi/qla2xxx/qla_nvme.c
> index 5cc1bbb1ed74..db8b802b147c 100644
> --- a/drivers/scsi/qla2xxx/qla_nvme.c
> +++ b/drivers/scsi/qla2xxx/qla_nvme.c
> @@ -555,8 +555,11 @@ static int qla_nvme_post_cmd(struct nvme_fc_local_port *lport,
>  
>  	fcport = qla_rport->fcport;
>  
> -	if (!qpair || !fcport || (qpair && !qpair->fw_started) ||
> +	if ((qpair && !qpair->fw_started) ||
>  	    (fcport && fcport->deleted))
> +		return -EBUSY;
> +
> +	if (!qpair || !fcport)
>  		return rval;
>  
>  	vha = fcport->vha;
> 

This does not appear to be cut against the latest for-next/staging; "rval" 
is not used there for the initial set of returns.

Anyway, returning EBUSY is the right way to go.

Regards,
-Arun

Re: [PATCH] qla2xxx: Return EBUSY on fcport deletion

[Daniel Wagner]

On Mon, Oct 12, 2020 at 09:07:15AM -0700, Arun Easi wrote:
> This does not appear to be cut against the latest for-next/staging; "rval" 
> is not used there for the initial set of returns.

Indeed, forgot to use staging. It's against queue. Let me update it.

> Anyway, returning EBUSY is the right way to go.

Thanks for the confirmation.

Daniel