Merge tag 'rxrpc-rewrite-20160622-2' of git://git.kernel.org/pub/scm/linux/kernel...

Merge tag 'rxrpc-rewrite-20160622-2' of git://git./linux/kernel/git/dhowells/linux-fs

David Howells says:

====================
rxrpc: Get rid of conn bundle and transport structs

Here's the next part of the AF_RXRPC rewrite.  The primary purpose of this
set is to get rid of the rxrpc_conn_bundle and rxrpc_transport structs.
This simplifies things for future development of the connection handling.

To this end, the following significant changes are made:

 (1) The rxrpc_connection struct is given pointers to the local and peer
     endpoints, inside the rxrpc_conn_parameters struct.  Pointers to the
     transport's copy of these pointers are then redirected to the
     connection struct.

 (2) Exclusive connection handling is fixed.  Exclusive connections should
     do just one call and then be retired.  They are used in security
     negotiations and, I believe, the idea is to avoid reuse of negotiated
     security contexts.

     The current code is doing a single connection per socket and doing all
     the calls over that.  With this change it gets a new connection for
     each call made.

 (3) A new sendmsg() control message marker is added to make individual
     calls operate over exclusive connections.  This should be used in
     future in preference to the sockopt that marks a socket as "exclusive
     connection".

 (4) IDs for client connections initiated by a machine are now allocated
     from a global pool using the IDR facility and are unique across all
     client connections, no matter their destination.  The IDR facility is
     then used to look up a connection on the connection ID alone.  Other
     parameters are then verified afterwards.

     Note that the IDR facility may use a lot of memory if the IDs it holds
     are widely scattered.  Given this, in a future commit, client
     connections will be retired if they are more than a certain distance
     from the last ID allocated.

     The client epoch is advanced by 1 each time the client ID counter
     wraps.  Connections outside the current epoch will also be retired in
     a future commit.

 (5) The connection bundle concept is removed and the client connection
     tree is moved into the local endpoint.  The queue for waiting for a
     call channel is moved to the rxrpc_connection struct as there can only
     be one connection for any particular key going to any particular peer
     now.

 (6) The rxrpc_transport struct is removed and the service connection tree
     is moved into the peer struct.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>