[PATCH RFC bpf-next 0/9] Introduce XDP-hints via BTF

[Jesper Dangaard Brouer <brouer@redhat.com>]

This patchset expose the traditional hardware offload hints to XDP and
rely on BTF to expose the layout to users.  More advanced use-case with
driver specific offloads will likely be in followup patches.

The users/consumers are (as described in [1]):
 - XDP BPF-progs
 - XDP to SKB conversion gaining HW offloads
 - AF_XDP can consume BTF info in userspace
 - Chained BPF-progs can communicate state via metadata

This is still RFC as the following features are missing:
 - Exposing XDP-hints indication in AF_XDP descriptor
 - Exporting what XDP-hints structs are avail per driver

Two drivers i40e and mvneta gets XDP-hints in this patchset.

[1] https://github.com/xdp-project/xdp-project/blob/master/conference/LLC2022/xdp_hints_hw_metadata-final.pdf

---

Jesper Dangaard Brouer (8):
      i40e: Refactor i40e_ptp_rx_hwtstamp
      bpf: export btf functions for modules
      net: create xdp_hints_common and set functions
      net: add net_device feature flag for XDP-hints
      xdp: controlling XDP-hints from BPF-prog via helper
      i40e: refactor i40e_rx_checksum with helper
      i40e: add XDP-hints handling
      net: use XDP-hints in xdp_frame to SKB conversion

Lorenzo Bianconi (1):
      mvneta: add XDP-hints support


 drivers/net/ethernet/intel/i40e/i40e.h      |   1 +
 drivers/net/ethernet/intel/i40e/i40e_main.c |  34 +++
 drivers/net/ethernet/intel/i40e/i40e_ptp.c  |  36 +++-
 drivers/net/ethernet/intel/i40e/i40e_txrx.c | 222 ++++++++++++++++----
 drivers/net/ethernet/marvell/mvneta.c       |  61 +++++-
 include/linux/btf.h                         |   2 +
 include/linux/netdev_features.h             |   3 +-
 include/net/xdp.h                           | 181 +++++++++++++++-
 include/uapi/linux/bpf.h                    |  43 ++++
 kernel/bpf/btf.c                            |  13 +-
 net/core/filter.c                           |  45 ++++
 net/core/xdp.c                              |  73 ++++++-
 net/ethtool/common.c                        |   1 +
 13 files changed, 644 insertions(+), 71 deletions(-)

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