[dm-devel] Re: [PATCH RFC 0/4] use scatter lists for all block pc requests and simplify hw handlers

Mike Christie michaelc at cs.wisc.edu
Wed Jun 8 12:46:50 UTC 2005


Jens Axboe wrote:
> On Tue, Jun 07 2005, Michael Christie wrote:
> 
>>Quoting James Bottomley <James.Bottomley at SteelEye.com>:
>>
>>
>>>On Tue, 2005-06-07 at 13:10 +0100, Christoph Hellwig wrote:
>>>
>>>>shouldn't blk_rq_map_kern handle a 0 buffer and do nothing more than
>>>>blk_get_request?  It's not exactly a criticial fastpath and that would make
>>>
>>>life
>>>
>>>>easier for the callers.
>>>
>>>Yes ... and it should probably do bio bouncing as well, since there's
>>>nothing special we have to do on completion to clean it up.
>>
>>ok. I just made it like the existing blk_rq_map_user which made the caller do
>>those things.
> 
> 
> I agree with Christoph, makes it nicer for blk_rq_map_user as well. I'll
> change the latter if you fix the former.

ok will do.




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