Re: [PATCH 3/5] ibmvfc: Send cancel when link is down

[Robert Jennings <rcj@linux.vnet.ibm.com>]

* Brian King (brking@linux.vnet.ibm.com) wrote:
> 
> If attempting to abort requests due to a fail fail timeout
> or error handling while the link is down, we cannot send
> an abort out on the fabric. We can, however, send a cancel
> to the VIOS. This fixes ibmvfc to send a cancel in this
> case to prevent error handling from failing and/or
> escalating.
> 
> Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Acked-by: Robert Jennings <rcj@linux.vnet.ibm.com>
> ---
> 
>  drivers/scsi/ibmvscsi/ibmvfc.c |   13 ++++++++-----
>  1 file changed, 8 insertions(+), 5 deletions(-)
> 
> diff -puN drivers/scsi/ibmvscsi/ibmvfc.c~ibmvfc_cancel_when_link_down drivers/scsi/ibmvscsi/ibmvfc.c
> --- linux-2.6/drivers/scsi/ibmvscsi/ibmvfc.c~ibmvfc_cancel_when_link_down	2013-01-23 08:12:09.000000000 -0600
> +++ linux-2.6-bjking1/drivers/scsi/ibmvscsi/ibmvfc.c	2013-01-23 09:18:46.000000000 -0600
> @@ -2179,7 +2179,7 @@ static int ibmvfc_cancel_all(struct scsi
>  		return 0;
>  	}
> 
> -	if (vhost->state == IBMVFC_ACTIVE) {
> +	if (vhost->logged_in) {
>  		evt = ibmvfc_get_event(vhost);
>  		ibmvfc_init_event(evt, ibmvfc_sync_completion, IBMVFC_MAD_FORMAT);
> 
> @@ -2190,7 +2190,10 @@ static int ibmvfc_cancel_all(struct scsi
>  		tmf->common.length = sizeof(*tmf);
>  		tmf->scsi_id = rport->port_id;
>  		int_to_scsilun(sdev->lun, &tmf->lun);
> -		tmf->flags = (type | IBMVFC_TMF_LUA_VALID);
> +		if (vhost->state == IBMVFC_ACTIVE)
> +			tmf->flags = (type | IBMVFC_TMF_LUA_VALID);
> +		else
> +			tmf->flags = IBMVFC_TMF_LUA_VALID;
>  		tmf->cancel_key = (unsigned long)sdev->hostdata;
>  		tmf->my_cancel_key = (unsigned long)starget->hostdata;
> 
> @@ -2389,7 +2392,7 @@ static int ibmvfc_eh_abort_handler(struc
>  {
>  	struct scsi_device *sdev = cmd->device;
>  	struct ibmvfc_host *vhost = shost_priv(sdev->host);
> -	int cancel_rc, block_rc, abort_rc = 0;
> +	int cancel_rc, block_rc;
>  	int rc = FAILED;
> 
>  	ENTER;
> @@ -2397,11 +2400,11 @@ static int ibmvfc_eh_abort_handler(struc
>  	ibmvfc_wait_while_resetting(vhost);
>  	if (block_rc != FAST_IO_FAIL) {
>  		cancel_rc = ibmvfc_cancel_all(sdev, IBMVFC_TMF_ABORT_TASK_SET);
> -		abort_rc = ibmvfc_abort_task_set(sdev);
> +		ibmvfc_abort_task_set(sdev);
>  	} else
>  		cancel_rc = ibmvfc_cancel_all(sdev, 0);
> 
> -	if (!cancel_rc && !abort_rc)
> +	if (!cancel_rc)
>  		rc = ibmvfc_wait_for_ops(vhost, sdev, ibmvfc_match_lun);
> 
>  	if (block_rc == FAST_IO_FAIL && rc != FAILED)
> _