Executes the backchannel task on the RPC state machine using
the existing open connection previously established by the client.
Signed-off-by: NRicardo Labiaga <ricardo.labiaga@netapp.com>

nfs41: Add bc_svc.o to sunrpc Makefile.

[nfs41: bc_send() does not need to be exported outside RPC module]
[nfs41: xprt_free_bc_request() need not be exported outside RPC module]
Signed-off-by: NRicardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[Update copyright]
Signed-off-by: NRicardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>

Contains prototype for backchannel helper routines.
Signed-off-by: NRicardo Labiaga <ricardo.labiaga@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfs41: xprt_setup_backchannel v4.0 only inline]
    Fix compile error when CONFIG_NFS_V4_1 is not set.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[Update Copyright notice and fix formatting]
Signed-off-by: NRicardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>