Re: [PATCH v2 1/3] scsi_cmnd: Introduce scsi_transfer_length helper

[Mike Christie <michaelc@cs.wisc.edu>]

On 06/24/2014 12:00 PM, Mike Christie wrote:
> On 06/24/2014 11:30 AM, Christoph Hellwig wrote:
>> On Tue, Jun 24, 2014 at 07:27:46PM +0300, Sagi Grimberg wrote:
>>> This condition only matters in the bidi case, which is not relevant for the
>>> PI case.
>>> I suggested to condition that in libiscsi (posted in the second thread,
>>> copy-paste below).
>>> Although I do agree that scsi_transfer_length() helper is not really just
>>> for PI and not more.
>>> I think Mike's way is cleaner.
>>
>> But for bidi there are two transfers.  So either scsi_transfer_length()
>> needs to take the scsi_data_buffer, or we need to avoid using it.
>>
>> For 3.16 I'd prefer something like you're patch below.  This patch which
>> has been rushed in last minute and not through the scsi tree has already
>> causes enough harm.  If you can come up with a clean version to
>> transparently handle the bidi case I'd be happy to pick that up for
>> 3.17.
>>
>> In the meantime please provide a version of the patch below with a
>> proper description and signoff.
>>
> 
> It would be nice to just have one function to call and it just do the
> right thing for the drivers. I am fine with Sagi's libiscsi patch for
> now though:
> 
> Acked-by: Mike Christie <michaelc@cs.wisc.edu>

Actually, let me take this back for a second. I am not sure if that is
right.