[ofa-general] Fast Reg Question

[Roland Dreier]

 > I'm a little perplexed by the fast reg WR definition. The context is
 > that I'm using the Fast Reg verb to map the local memory that is the
 > data source for an RDMA_WRITE.
 > 
 > The WR format, however, only takes an rkey. How does this all work
 > when you're using fast reg to map local memory? Does the WR really
 > need the mr pointer, or both the lkey and rkey? The IBTA spec seems to
 > indicate that it needs more information about the MR than just the
 > rkey.

On Mellanox, L_Key and R_Key are always the same, so it doesn't really
matter.  I think in general the idea would be that the L_Key you have
gets updatedd with any "consumer key" changes you make in the WR but
otherwise works the same.  the WR processing better be able to find the
MR by R_Key so I think it's OK.

I'll look at the IB spec though.

 - R.