Re: [PATCH] dm-mpath-rdac: don't stomp on a request's transfer bit.

[Chandra Seetharaman <sekharan@us.ibm.com>]

ACK'd. This patch is needed for rdac to work properly.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>

On Tue, 2007-07-17 at 14:07 -0700, Andrew Vasquez wrote:
> Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
> ---
> 
> 	On Thu, 12 Jul 2007, Mike Anderson wrote:
> 
> 	> Copying this mail to linux-scsi and Ccing Andrew Vasquez to possibly
> 	> provide input on the Qlogic behavior.
> 	...
> 
> 	> > > Jul 12 17:11:15 jimbo kernel: qla2xxx 0000:02:01.1: ISP System Error - mbx1=0h
> 	> > > mbx2=8012h mbx3=8002h.
> 	> > > Jul 12 17:11:15 jimbo kernel: qla2xxx 0000:02:01.1: Firmware has been previously
> 	> > > dumped (ffffc2000171d000) -- ignoring request...
> 	> > > Jul 12 17:11:16 jimbo kernel: qla2xxx 0000:02:01.1: Performing ISP error
> 	> > > recovery - ha= ffff81007e85c530.
> 
> 	So what's happening here is the firmware is detecting a Xfer-ready
> 	from the storage when in fact the data-direction for a mode-select
> 	should be a write (DATA_OUT).
> 
> 	The following patch fixes the problem (typo).  Verified by Brian, as
> 	well.
> 
> diff --git a/drivers/md/dm-mpath-rdac.c b/drivers/md/dm-mpath-rdac.c
> index 8b776b8..16b1613 100644
> --- a/drivers/md/dm-mpath-rdac.c
> +++ b/drivers/md/dm-mpath-rdac.c
> @@ -292,7 +292,7 @@ static struct request *get_rdac_req(struct rdac_handler *h,
>  	rq->end_io_data = h;
>  	rq->timeout = h->timeout;
>  	rq->cmd_type = REQ_TYPE_BLOCK_PC;
> -	rq->cmd_flags = REQ_FAILFAST | REQ_NOMERGE;
> +	rq->cmd_flags |= REQ_FAILFAST | REQ_NOMERGE;
>  	return rq;
>  }
> 
> 
-- 

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    Chandra Seetharaman               | Be careful what you choose....
              - sekharan@us.ibm.com   |      .......you may get it.
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