Re: [RFC 1/9] zfcp: drop unsuitable scsi_cmnd usage from SCSI traces for scsi_eh / TMF

[Hannes Reinecke <hare@suse.de>]

On 07/25/2017 04:14 PM, Steffen Maier wrote:
> The SCSI command pointer passed to scsi_eh callbacks is just one arbitrary
> command of potentially many that are in the eh queue to be processed.
> The command is only used to indirectly pass the TMF scope in terms of
> SCSI ID/target and SCSI LUN for LUN reset.
> 
> Hence, zfcp had filled in SCSI trace record fields which do not really
> belong to the TMF. This was confusing.
> 
> Therefore, refactor the TMF tracing to work without SCSI command
> and instead pass explicit arguments for SCSI ID and SCSI LUN.
> As context we now need a pointer to zfcp_adapter.
> To make it even clearer, we set all bits to 1 for the fields, which do
> not belong to the TMF, to indicate that these fields are invalid.
> 
> The old zfcp_dbf_scsi() became zfcp_dbf_scsi_common() to now handle both
> SCSI commands and TMFs. The old argument scsi_cmnd is now optional and
> can be NULL with TMFs. Two new arguments scsi_id and scsi_lun are
> optional and only used if scsi_cmnd is NULL, i.e. with TMFs.
> 
> Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
> ---
>  drivers/s390/scsi/zfcp_dbf.c  | 51 ++++++++++++++++++++++++++++---------------
>  drivers/s390/scsi/zfcp_dbf.h  | 26 +++++++++++++++-------
>  drivers/s390/scsi/zfcp_ext.h  |  8 ++++---
>  drivers/s390/scsi/zfcp_scsi.c | 20 ++++++++++++-----
>  4 files changed, 71 insertions(+), 34 deletions(-)
> 
Reviewed-by: Hannes Reinecke <hare@suse.com>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		   Teamlead Storage & Networking
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