[ofa-general] [PATCH] for-2.6.23 ib/umad: add partition support

[Roland Dreier]

 > Did you have something in mind?  (new ioctl?  re-using existing fields?)
 > 
 > Not all fields are used for both reads and writes.  E.g. status is
 > unused on a write, and retries is unused on a read.  Storing the
 > pkey_index on a read seems doable.  I think if we do anything on a
 > write, we need to make an assumption that the data is currently set to
 > 0 by the app.

I hadn't really thought about it.

One other thing is that the top 8 bits of flow_label aren't used.  I
guess we could steal that, although it's a little ugly.  I doubt it
would break existing userspace.

There is the problem of old kernels silently ignoring the pkey index
though.  I'm not sure I see a good way around that.

I'm beginning to think that just updating the ABI might be the right
answer.  But let's try to make this be the last ABI break.  Are we
pretty sure there's *nothing* else we might ever want to add to the
structure?  I can't think of anything right now...

 - R.