Re: [RFC] iscsi transport : add sgio pass-thru support

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

James Smart wrote:
> I actually started the patch with this in mind - making a common layer.  
> I was able to commonize:  xx_bsg_destroy_job(), xx_bsg_jobdone(), 
> xx_softirq_done(), a helper for the timeout function (chkjobdone()), 
> xx_bsg_map_buffer(), xx_req_to_bsgjob(), and xx_bsg_goose_queue().
> 
> However, what I was finding was I was jumping through hoops with the 
> data structures (whose header where, structures within structures, 
> nested private areas, etc).  Additionally, I kept finding chunks of the 
> code flow, which had parallels to the items in the common routines, that 
> had to be left within the transport (e.g. rx path in transport, tx in 
> common; or vice versa) - e.g. if I can't encapsulate both sides of the 
> code flow within the common code I lose many of the advantages - I ended 
> up abandoning it  under the guise of "complexity==bad"
> 
> I can post some of the work to see if you have the same conclusion. Yes, 
> I don't like the replication either.
> 

Do not worry about it. I am looking at it in more depth now.