InfiniBand Implementations

Well, as I asked about HyperTransport, I shall ask about InfiniBand :-)

As previous threads demonstrated, the InfiniBand specification attempts
to be all things to all me, but it was and is very clear that the way
it is going to be used is that implementors of devices, software and
perhaps even interfaces will make assumptions about which subsets they
are going to use and optimise or even support accordingly.  Just as
happened with SCSI.

My specific question is about the software designs, and the way that
the hardware interfaces intend that the software should use them.  In
particular, that dreaded question of user-space DMA, with its related
issues of whether the user can provide arbitrary locations for DMA
use, the scope of pinning of such locations, what support there is for
memory migration or swapping and so on.

Has anyone started to document any of that yet?  Because it is obviously
a prerequisite for writing (or even designing) efficient and robust
code to use InfiniBand.


Regards,
Nick Maclaren.