After some discussion with David Howells at LSF/MM 2023, we arrived at a plan to use a single sock_sendmsg() call for transmitting an RPC message on socket-based transports. This is an initial part of the transition to support handling folios with file content, but it has scalability benefits as well. This series passes the usual set of NFS-based tests. I've found no behavior regressions so far. From the netdev folks, I'm interested to know if this approach is sensible. The next step is performance benchmarking. Changes since RFC: * Moved xdr_buf-to-bio_vec array helper to generic XDR code * Added bio_vec array bounds-checking * Re-ordered patches --- Chuck Lever (4): SUNRPC: Convert svc_tcp_sendmsg to use bio_vecs directly SUNRPC: Send RPC message on TCP with a single sock_sendmsg() call SUNRPC: Convert svc_udp_sendto() to use the per-socket bio_vec array SUNRPC: Use a per-transport receive bio_vec array include/linux/sunrpc/svc.h | 1 - include/linux/sunrpc/svcsock.h | 7 +++ include/linux/sunrpc/xdr.h | 2 + net/sunrpc/svcsock.c | 111 ++++++++++++++------------------- net/sunrpc/xdr.c | 50 +++++++++++++++ 5 files changed, 107 insertions(+), 64 deletions(-) -- Chuck Lever