++@Gregory Etelson Regards, Maayan Kashani
> -----Original Message----- > From: László Molnár <laszlo.mol...@ericsson.com> > Sent: Wednesday, 8 May 2024 18:24 > To: users@dpdk.org > Subject: mlx5: is GTP encapsulation possible using the rte_flow api? > > Hi All, > > I wonder whether it would be possible to implement HW accelerated GTP > encapsulation (as a first step) functionality using a Bluefield 2 NIC and the > rte_flow API? > > The encapsulation would need to work between different ports using hairpin > queues. > > Let's say I already have the rules in dpdk-testpmd that remove the original > ETH header using raw_decap, and add the new ETH/IP/UDP/GTP using > raw_encap. > > Now I would need to update some header fields (payload length for ipv4, > udp, gtp). I would use "modify_field op add", but I found no way I can access > the payload length field for UDP and GTP. > > For example, when I try to access the UDP payload length field by using > "dst_type udp_port_src dst_offset 32" in the "modify_field" action, I get a > "destination offset is too big: Invalid argument" error. > > This seems to be caused by a check in the mlx5 driver, which is a bit > surprising > as the documentation in rte_flow.rst (DPDK version 24.03) says that: > > ``offset`` allows going past the specified packet field boundary to > copy a field to an arbitrary place in a packet, > > Is this just a driver limitation or an HW limitation? Or could a flex item > solve > this? > > Thanks, Laszlo
