Problem with ALUA Handler

Problem with ALUA Handler

[Pradipmaya Maharana]

Hi,

I tried compiling ALUA handler code from Hannes Reincke
(https://www.redhat.com/archives/dm-devel/2007-October/msg00033.html)
on kernel 2.6.18 and with few modifications it did fine.

I was even able to load it, but it fails for the std inquiry and hence
does not do anything further. It returns error that the controller
does not support TPGS.

I verified with the analyser that the inquiry command is actually
reaching the controller and it's returning proper values.

Could someone please let me know what am I missing here?

Thanks and Regards,
Pradipmaya.

Re: Problem with ALUA Handler

[Hannes Reinecke]

Pradipmaya Maharana wrote:
> Hi,
> 
> I tried compiling ALUA handler code from Hannes Reincke
> (https://www.redhat.com/archives/dm-devel/2007-October/msg00033.html)
> on kernel 2.6.18 and with few modifications it did fine.
> 
> I was even able to load it, but it fails for the std inquiry and hence
> does not do anything further. It returns error that the controller
> does not support TPGS.
> 
This is preliminary code only. I've done a rework of the ALUA handler
and will post the updated code here shortly.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		      zSeries & Storage
hare@suse.de			      +49 911 74053 688
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg
GF: Markus Rex, HRB 16746 (AG Nürnberg)

Re: Problem with ALUA Handler

[Pradipmaya Maharana]

Thanks Hannes.

Actually I could get it to work after making some changes;
In the function prepare_req(), I replaced

//rq->cmd_flags |= REQ_FAILFAST | REQ_NOMERGE;
	rq->flags |= REQ_FAILFAST | REQ_NOMERGE;

with following:

rq->flags |= REQ_BLOCK_PC | REQ_SPECIAL | REQ_QUIET;

This worked for me.

Thanks for your support.
Regards,
Pradipmaya.

On 11/9/07, Hannes Reinecke <hare@suse.de> wrote:
> Pradipmaya Maharana wrote:
> > Hi,
> >
> > I tried compiling ALUA handler code from Hannes Reincke
> > (https://www.redhat.com/archives/dm-devel/2007-October/msg00033.html)
> > on kernel 2.6.18 and with few modifications it did fine.
> >
> > I was even able to load it, but it fails for the std inquiry and hence
> > does not do anything further. It returns error that the controller
> > does not support TPGS.
> >
> This is preliminary code only. I've done a rework of the ALUA handler
> and will post the updated code here shortly.
>
> Cheers,
>
> Hannes
> --
> Dr. Hannes Reinecke                   zSeries & Storage
> hare@suse.de                          +49 911 74053 688
> SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg
> GF: Markus Rex, HRB 16746 (AG Nürnberg)
>
> --
> dm-devel mailing list
> dm-devel@redhat.com
> https://www.redhat.com/mailman/listinfo/dm-devel
>

Re: Problem with ALUA Handler

[Hannes Reinecke]

Pradipmaya Maharana wrote:
> Thanks Hannes.
> 
> Actually I could get it to work after making some changes;
> In the function prepare_req(), I replaced
> 
> //rq->cmd_flags |= REQ_FAILFAST | REQ_NOMERGE;
> 	rq->flags |= REQ_FAILFAST | REQ_NOMERGE;
> 
> with following:
> 
> rq->flags |= REQ_BLOCK_PC | REQ_SPECIAL | REQ_QUIET;
> 
> This worked for me.
> 

Errm. Which version you're compiling against?
The hardware handler is done against scsi-misc; by the
looks of it you're compiling against some older version
(2.6.19? 2.6.16?)

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		      zSeries & Storage
hare@suse.de			      +49 911 74053 688
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg
GF: Markus Rex, HRB 16746 (AG Nürnberg)

Re: Problem with ALUA Handler

[Pradipmaya Maharana]

Yes, you are right. I am evaluating it on 2.6.18 (that explains why
the changes work);
I am willing to wait for your patch but have no idea which release of
linux would include it.

Could you please let me know.

Thank and Regards,
Pradipmaya.

On 11/11/07, Hannes Reinecke <hare@suse.de> wrote:
> Pradipmaya Maharana wrote:
> > Thanks Hannes.
> >
> > Actually I could get it to work after making some changes;
> > In the function prepare_req(), I replaced
> >
> > //rq->cmd_flags |= REQ_FAILFAST | REQ_NOMERGE;
> >       rq->flags |= REQ_FAILFAST | REQ_NOMERGE;
> >
> > with following:
> >
> > rq->flags |= REQ_BLOCK_PC | REQ_SPECIAL | REQ_QUIET;
> >
> > This worked for me.
> >
>
> Errm. Which version you're compiling against?
> The hardware handler is done against scsi-misc; by the
> looks of it you're compiling against some older version
> (2.6.19? 2.6.16?)
>
> Cheers,
>
> Hannes
> --
> Dr. Hannes Reinecke                   zSeries & Storage
> hare@suse.de                          +49 911 74053 688
> SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg
> GF: Markus Rex, HRB 16746 (AG Nürnberg)
>
> --
> dm-devel mailing list
> dm-devel@redhat.com
> https://www.redhat.com/mailman/listinfo/dm-devel
>