[ofa-general] Re: IB/core: Add creation flags to QPs

[Hoang-Nam Nguyen]

Hello Roland!
> Jack Morgenstein wrote:
> > Actually, we did not break the ABI for XRC (we had to do cartwheels to
avoid
> > this, but what the heck).
> > ....
> > You can avoid doing this in one of 2 ways:
> > Either:  create a new QP type
> > Or:      add new verbs to the core.
> Jack - OK, got it, and thanks a lot! for the coaching.
>
> Roland - in the case of the connectx block loopback feature, it seems
> that the simplest way to go would for user space is to create a new QP
> type IB_QPT_UD_BL[block-loopback] which is translated by the uverbs
> layer to what ever scheme we decide on for the kernel (eg create_flags,
> qp_types, bit fields, etc). As for IPoIB, it would create a UD/LSO/BL
> QP, thoughts?
What is your recommendation wrt/ encoding scheme for qp_type and
create_flags?
For ehca we need user space support for LL QP. And we can implement that
as a flag (my favorite) or as two additional qp_types (IB_QPT_UD_LL and
IB_QPT_RC_LL). Anyway I'm flexible in whatever approach you choose.
PS: See also this thread
http://lists.openfabrics.org/pipermail/general/2008-March/048445.html

Thanks!
Nam