tree b6394fe31cdf2560533abfa37c35cab3f08f406a
parent a5b027e1897c811401862877d0ba4ca26fabc4da
author Chuck Lever <chuck.lever@oracle.com> 1445722055 -0400
committer Anna Schumaker <Anna.Schumaker@Netapp.com> 1446489915 -0500

SUNRPC: Abstract backchannel operations

xprt_{setup,destroy}_backchannel() won't be adequate for RPC/RMDA
bi-direction. In particular, receive buffers have to be pre-
registered and posted in order to receive incoming backchannel
requests.

Add a virtual function call to allow the insertion of appropriate
backchannel setup and destruction methods for each transport.

In addition, freeing a backchannel request is a little different
for RPC/RDMA. Introduce an rpc_xprt_op to handle the difference.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Tested-By: Devesh Sharma <devesh.sharma@avagotech.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>