Re: Kernel fast memory registration API proposal [RFC]

[Sagi Grimberg <sagig-LDSdmyG8hGV8YrgS2mwiifqBs+8SCbDb@public.gmane.org>]

On 7/20/2015 7:23 PM, Jason Gunthorpe wrote:
> On Sun, Jul 19, 2015 at 08:33:24AM +0300, Sagi Grimberg wrote:
>> I was thinking that the user won't explicitly say which key it registers
>> and it will be decided from the registration itself.
>> Meaning, the registration code will do:
>
> Please don't..
>
>> if (access | (IB_ACCESS_REMOTE_READ | IB_ACCESS_REMOTE_WRITE)
>>          register rkey...
>> else
>>          register lkey...
>>
>> Will that work with iWARP? or will this break because
>> iWARP needs REMOTE_WRITE for lkeys?
>
> Right, it will break.
>
> Access flags are only weakly related to lkey/rkey.
>
> It needs to be explicit. We have spots in the API that take lkeys and
> other spots the take rkeys - the caller must always know the intended
> use of the key it is requesting, there is no reason not to describe
> that explicitly.

OK, keep it explicit. got it.
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