xdp: introduce xdp-feature support

Introduce the capability to export the XDP features supported by the NIC. Introduce a XDP compliance test tool (xdp_features) to check the features exported by the NIC match the real features supported by the driver. Allow XDP_REDIRECT of non-linear XDP frames into a devmap. Export XDP features for each XDP capable driver.
Extend libbpf netlink implementation in order to support netlink_generic protocol.
Introduce a simple generic netlink family for netdev data.

Changes since RFCv2:
- do not assume fixed layout for genl kernel messages
- fix warnings in netdev_nl_dev_fill
- fix capabilities for nfp driver
- add supported_sg parameter to xdp_features_set_redirect_target and drop __xdp_features_set_redirect_target routine

Changes since RFCv1:
- Introduce netdev-genl implementation and get rid of rtnl one.
- Introduce netlink_generic support in libbpf netlink implementation
- Rename XDP_FEATURE_* in NETDEV_XDP_ACT_*
- Rename XDP_FEATURE_REDIRECT_TARGET in NETDEV_XDP_ACT_NDO_XMIT
- Rename XDP_FEATURE_FRAG_RX in NETDEV_XDP_ACT_RX_SG
- Rename XDP_FEATURE_FRAG_TARFET in NETDEV_XDP_ACT_NDO_XMIT
- Get rid of XDP_LOCK feature.
- Move xdp_feature field in a netdevice struct hole in the 4th cacheline.

Jakub Kicinski (1):
netdev-genl: create a simple family for netdev stuff

Lorenzo Bianconi (4):
libbpf: add the capability to specify netlink proto in
libbpf_netlink_send_recv
libbpf: add API to get XDP/XSK supported features
bpf: devmap: check XDP features in bpf_map_update_elem and
__xdp_enqueue
selftests/bpf: introduce XDP compliance test tool

Marek Majtyka (2):
drivers: net: turn on XDP features
xsk: add usage of XDP features flags

 Documentation/netlink/specs/netdev.yaml       |  72 ++
 drivers/net/ethernet/amazon/ena/ena_netdev.c  |   5 +
 .../net/ethernet/aquantia/atlantic/aq_nic.c   |   4 +
 drivers/net/ethernet/broadcom/bnxt/bnxt.c     |   2 +
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c |   2 +
 .../net/ethernet/cavium/thunder/nicvf_main.c  |   2 +
 .../net/ethernet/freescale/dpaa/dpaa_eth.c    |   2 +
 .../net/ethernet/freescale/dpaa2/dpaa2-eth.c  |   1 +
 .../net/ethernet/freescale/enetc/enetc_pf.c   |   2 +
 .../ethernet/fungible/funeth/funeth_main.c    |   6 +
 drivers/net/ethernet/intel/i40e/i40e_main.c   |  10 +-
 drivers/net/ethernet/intel/ice/ice_main.c     |   5 +
 drivers/net/ethernet/intel/igb/igb_main.c     |  10 +-
 drivers/net/ethernet/intel/igc/igc_main.c     |   2 +
 drivers/net/ethernet/intel/igc/igc_xdp.c      |   5 +
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c |   5 +
 .../net/ethernet/intel/ixgbevf/ixgbevf_main.c |   1 +
 drivers/net/ethernet/marvell/mvneta.c         |   2 +
 .../net/ethernet/marvell/mvpp2/mvpp2_main.c   |   3 +
 .../ethernet/marvell/octeontx2/nic/otx2_pf.c  |   8 +-
 drivers/net/ethernet/mediatek/mtk_eth_soc.c   |   5 +
 .../net/ethernet/mellanox/mlx4/en_netdev.c    |   2 +
 .../net/ethernet/mellanox/mlx5/core/en_main.c |  10 +
 drivers/net/ethernet/microsoft/mana/mana_en.c |   1 +
 .../ethernet/netronome/nfp/nfp_net_common.c   |   5 +
 drivers/net/ethernet/qlogic/qede/qede_main.c  |   2 +
 drivers/net/ethernet/sfc/efx.c                |   3 +
 drivers/net/ethernet/sfc/siena/efx.c          |   3 +
 drivers/net/ethernet/socionext/netsec.c       |   2 +
 .../net/ethernet/stmicro/stmmac/stmmac_main.c |   1 +
 drivers/net/ethernet/ti/cpsw.c                |   2 +
 drivers/net/ethernet/ti/cpsw_new.c            |   3 +
 drivers/net/hyperv/netvsc_drv.c               |   2 +
 drivers/net/netdevsim/netdev.c                |   1 +
 drivers/net/tun.c                             |   4 +
 drivers/net/veth.c                            |   3 +
 drivers/net/virtio_net.c                      |   5 +
 drivers/net/xen-netfront.c                    |   1 +
 include/linux/netdevice.h                     |   2 +
 include/net/xdp.h                             |  34 +
 include/uapi/linux/netdev.h                   |  66 ++
 kernel/bpf/devmap.c                           |  25 +-
 net/core/Makefile                             |   3 +-
 net/core/filter.c                             |  13 +-
 net/core/netdev-genl-gen.c                    |  48 ++
 net/core/netdev-genl-gen.h                    |  23 +
 net/core/netdev-genl.c                        | 178 +++++
 net/xdp/xsk_buff_pool.c                       |   3 +-
 tools/include/uapi/linux/netdev.h             |  66 ++
 tools/lib/bpf/libbpf.h                        |   3 +-
 tools/lib/bpf/netlink.c                       | 121 ++-
 tools/lib/bpf/nlattr.h                        |  12 +
 tools/testing/selftests/bpf/Makefile          |   5 +-
 .../selftests/bpf/progs/test_xdp_features.c   | 237 ++++++
 .../selftests/bpf/test_xdp_features.sh        |  99 +++
 tools/testing/selftests/bpf/xdp_features.c    | 743 ++++++++++++++++++
 56 files changed, 1852 insertions(+), 33 deletions(-)
 create mode 100644 Documentation/netlink/specs/netdev.yaml
 create mode 100644 include/uapi/linux/netdev.h
 create mode 100644 net/core/netdev-genl-gen.c
 create mode 100644 net/core/netdev-genl-gen.h
 create mode 100644 net/core/netdev-genl.c
 create mode 100644 tools/include/uapi/linux/netdev.h
 create mode 100644 tools/testing/selftests/bpf/progs/test_xdp_features.c
 create mode 100755 tools/testing/selftests/bpf/test_xdp_features.sh
 create mode 100644 tools/testing/selftests/bpf/xdp_features.c

2.39.0