Message-ID: <49F96E96.5040107@kernel.org>
Date: Thu, 30 Apr 2009 18:25:42 +0900
From: Tejun Heo <tj@kernel.org>
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To: petkovbb@gmail.com, Tejun Heo <tj@kernel.org>,
       James Bottomley <James.Bottomley@HansenPartnership.com>,
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Subject: Re: [PATCH 03/10] block: add rq->resid_len
References: <1240996428-10159-1-git-send-email-tj@kernel.org> <1240996428-10159-4-git-send-email-tj@kernel.org> <1241016114.3369.9.camel@mulgrave.int.hansenpartnership.com> <49F905EE.2020407@kernel.org> <20090430064549.GC6725@liondog.tnic> <49F95101.3010004@kernel.org> <20090430073719.GA9640@liondog.tnic>
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Borislav Petkov wrote:
>>> And I like it too, we've been coming up with all sorts of hacks in
>>> ide-atapi wrt to residual completion and accounting of what got xferred
>>> already and rq->resid_len is much more cleaner, IMHO.
>>>
>>> /me testing...
>> AFAICT, residual count handling in ide was most broken.

Oooh... It was "mostly broken" not "most broken".  Where went my l and
y?

> Tell me about it :).
> 
>> This patch doesn't fix anything other than making it report 0
>> resid_len on SG_IO which is usually better than reporting full
>> residual count. The only place inside ide where residual count is used
>> in the tape driver to determine actually transferred size. That part
>> works okay with the patch applied.
> 
>> Hmmm... maybe it's about time to finally clean up residual count
>> handling in ide and libata, which BTW doesn't do anything about it at
>> the moment.
> 
> Completely agreed. This doesn't do anything about it right now but
> with rq->resid_len in place I could get rid of a bunch of pc->xferred,
> cmd->nleft and similar on-stack structs we've been introducing, and use
> solely an rq in the LLD. I'll get to do some experimenting tomorrow and
> whip up some cleanup patches in order to see how it could look exactly.
> Stay tuned.

Yay, cool.  :-)

-- 
tejun
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