Re: [PATCH 2.6.25.1] Add scsi_execute_async_fifo()

[Vladislav Bolkhovitin <vst@vlnb.net>]

Boaz Harrosh wrote:
> Vladislav Bolkhovitin wrote:
>> Christoph Hellwig wrote:
>>> On Fri, May 02, 2008 at 05:53:22PM +0200, Bart Van Assche wrote:
>>>> Regarding scsi_execute_async(): I didn't know that this API is on its
>>>> way out. What will it be replaced by, and when ?
>>> blk_execute_rq/blk_execute_rq_nowait plus the block level helpers built
>>> ontop to build requests.
>> scsi_execute_async() is already a nice and simple helper function on top 
>> blk_execute_rq_nowait(). What's the point then to remove it? Do you 
>> consider that exposing scsi_execute_async() internals to its users is 
>> better?
>>
> 
> The problem with it is the use of sg list to *hack* in bio's. Which totally 
> ignores/duplicates block layer mechanisms. There is pending a large patchset
> that removes the use of scsi_execute_async from sg/sr and friends to use blk_map_*
> members and directly call blk_execute_*. The original patchset was written by
> Mike Christie but is now brought up to date by Tomo. It should be submitted soon I think.
> If you need good example of usage check out bsg.c it maps user-space data in all kind
> of combinations. If you have kernel space memory it is even simpler.

Thanks for pointing on it. But it still remained unclear for me what's 
the point in the scsi_execute_async() removal. Function 
scsi_req_map_sg() looks pretty simple and straightforward, so I don't 
see how the overall code can be simplified.

>>>> Bart.
>>> ---end quoted text---
>>>
> 
> If you need any help, please feel free to ask.
> 
> Boaz
> 
>