Receive buffer's physical address or iova will anyway not
go beyond 49bits, since it is the max supported HW address.
As per perf, updating bitfields i.e buf_addr:42 in RBDR
descriptor entry consumes lots of cpu cycles, hence changed
it to a 64bit field with alignment requirements taken care of.
Signed-off-by: Sunil Goutham <sgoutham@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>