Re: [patch ide-dev 8/9] make ide_task_ioctl() use REQ_DRIVE_TASKFILE

[Tejun Heo <htejun@gmail.com>]

  Hi,

Bartlomiej Zolnierkiewicz wrote:
> On Sunday 27 February 2005 08:36, Tejun Heo wrote:
> 
>> Hello, Bartlomiej.
>>
>> This patch should be modified to use flagged taskfile if the
>>task_end_request_fix patch isn't applied.  As non-flagged taskfile
>>won't return valid result registers, TASK ioctl users won't get the
>>correct register output.
> 
> 
> Nope, it works just fine because REQ_DRIVE_TASK used only
> no-data protocol, please check task_no_data_intr().
> 

  Sorry, I missed that.  IDE really has a lot of ways to finish a 
command, doesn't it?  hdio.txt is gonna look ugly. :-)

> 
>> IMHO, this flag-to-get-result-registers thing is way too subtle.  How
>>about keeping old behavior by just not copying out register outputs in
>>ide_taskfile_ioctl() in applicable cases instead of not reading
>>registers when ending commands?  That is, unless there's some
>>noticeable performance impacts I'm not aware of.
> 
> 
> This would miss whole point of not _reading_ these registers (IO is slow).
> IMHO new flags denoting {in,out} registers should be added (to <linux/ata.h>
> to share them with libata) so new code can be sane and old flags would map
> on new flags when needed.

  Please do it.

  Or, let me know what you have in mind (added fields, flag names, 
etc...); then, I'll do it.  I think we also need to hear Jeff's opinion 
as things need to be added to ata.h.

  Thanks.

-- 
tejun