On 03/31/2015 03:42 PM, Tom Talpey wrote: > On 3/31/2015 7:41 AM, Michael Wang wrote: >> [snip] > Yes, in fact the iWARP protocol does not preclude multiple read SGEs, > even though most iWARP implementations have chosen to support just one. > > Even for multi-SGE-capable adapters, there is a limit of SGL size, based > on the adapter's work request format and other factors. So my argument > is that upper layers can and should query that, not make a blanket > decision based on protocol type.
Thanks for the explanation Sounds like some new callback on device level like query_device() to acquire the right info. >> I currently only find this one place where infer max-read-sges from >> transport type, it looks more like a special case to me rather than a generic >> method we could exposed... and also not very related with IB management >> helper concept IMHO. > It is most certainly not a special case, but you could decide to > introduce it in many ways. I'm not commenting on that. > > My main concern is that you do not introduce a new and clumsy "is iWARP" > rule as an adapter-specific API requirement to expose the RDMA Read SGE > behavior. That's what your initial message seemed to imply? Yeah I planed to just use rdma_transport_iwarp() to replace the check, it's actually meaningless but just refine, frankly speaking I would prefer some driver developer to work on that part, at this point I prefer to focus on introducing the management helpers firstly Maybe we could mark it as a TODO temporarily, if later we found more scenes using similar logical, we can collect them and do some reform Regards, Michael Wang -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
