What is GetXid/FreeXid supposed to actually do?

As Christoph pointed out while looking at this code, we have a bunch of
calls in cifs to GetXid/FreeXid, but the xid's returned aren't actually
used for anything aside from the occasional debug message.

Not only that, but these values aren't even unique. It's easily
possible to have GetXid return the same number twice if a FreeXid is
called between the two calls. This would seem to elminate any value
that it has in logging too. Is there some purpose behind these that I'm
missing?

It seems like eliminating these, or replacing them with a call to a
standard routine that just does does debug messages would be a better
idea. We could then get rid of all xid's as function args in a ton of
places as well.

-- 
Jeff Layton <[email protected]>