On 04/18/2018 06:29 AM, Nikita V. Shirokov wrote: > In this patch series i'm add new bpf helper which allow to manupulate > xdp's data_end pointer. right now only "shrinking" (reduce packet's size > by moving pointer) is supported (and i see no use case for "growing"). > Main use case for such helper is to be able to generate controll (ICMP) > messages from XDP context. such messages usually contains first N bytes > from original packets as a payload, and this is exactly what this helper > would allow us to do (see patch 3 for sample program, where we generate > ICMP "packet too big" message). This helper could be usefull for load > balancing applications where after additional encapsulation, resulting > packet could be bigger then interface MTU. > Aside from new helper this patch series contains minor changes in device > drivers (for ones which requires), so they would recal packet's length > not only when head pointer was adjusted, but if tail's one as well.
The whole set doesn't have any SoBs from you which is mandatory before applying anything. Please add. Thanks, Daniel > v1->v2: > * fixed kbuild warning > * made offset eq 0 invalid for xdp_bpf_adjust_tail > * splitted bpf_prog_test_run fix and selftests in sep commits > * added SPDX licence where applicable > * some reshuffling in patches order (tests now in the end) > > > Nikita V. Shirokov (11): > bpf: making bpf_prog_test run aware of possible data_end ptr change > bpf: adding tests for bpf_xdp_adjust_tail > bpf: adding bpf_xdp_adjust_tail helper > bpf: make generic xdp compatible w/ bpf_xdp_adjust_tail > bpf: make mlx4 compatible w/ bpf_xdp_adjust_tail > bpf: make bnxt compatible w/ bpf_xdp_adjust_tail > bpf: make cavium thunder compatible w/ bpf_xdp_adjust_tail > bpf: make netronome nfp compatible w/ bpf_xdp_adjust_tail > bpf: make tun compatible w/ bpf_xdp_adjust_tail > bpf: make virtio compatible w/ bpf_xdp_adjust_tail > bpf: add bpf_xdp_adjust_tail sample prog > > drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c | 2 +- > drivers/net/ethernet/cavium/thunder/nicvf_main.c | 2 +- > drivers/net/ethernet/mellanox/mlx4/en_rx.c | 2 +- > .../net/ethernet/netronome/nfp/nfp_net_common.c | 2 +- > drivers/net/tun.c | 3 +- > drivers/net/virtio_net.c | 7 +- > include/uapi/linux/bpf.h | 10 +- > net/bpf/test_run.c | 3 +- > net/core/dev.c | 10 +- > net/core/filter.c | 29 +++- > samples/bpf/Makefile | 4 + > samples/bpf/xdp_adjust_tail_kern.c | 152 > +++++++++++++++++++++ > samples/bpf/xdp_adjust_tail_user.c | 142 +++++++++++++++++++ > tools/include/uapi/linux/bpf.h | 10 +- > tools/testing/selftests/bpf/Makefile | 2 +- > tools/testing/selftests/bpf/bpf_helpers.h | 5 + > tools/testing/selftests/bpf/test_adjust_tail.c | 30 ++++ > tools/testing/selftests/bpf/test_progs.c | 32 +++++ > 18 files changed, 435 insertions(+), 12 deletions(-) > create mode 100644 samples/bpf/xdp_adjust_tail_kern.c > create mode 100644 samples/bpf/xdp_adjust_tail_user.c > create mode 100644 tools/testing/selftests/bpf/test_adjust_tail.c >
