From: Willem de Bruijn <will...@google.com>
BPF allows for dynamic tunneling, choosing the tunnel destination and
features on-demand. Extend bpf_skb_adjust_room to allow for efficient
tunneling at the TC hooks.
Most features are required for large packets with GSO, as these will
be modified after this patch.
Patch 1
is a performance optimization, avoiding an unnecessary unclone
for the TCP hot path.
Patches 2..6
introduce a regression test. These can be squashed, but the code is
arguably more readable when gradually expanding the feature set.
Patch 7
is a performance optimization, avoid copying network headers
that are going to be overwritten. This also simplifies the bpf
program.
Patch 8
reenables bpf_skb_adjust_room for UDP packets.
Patch 9
configures skb tunneling metadata analogous to tunnel devices.
Patches 10..13
expand the regression test to make use of the new features and
enable the GSO testcases.
Changes
v1->v2
- move BPF_F_ADJ_ROOM_MASK out of uapi as it can be expanded
- document new flags
- in tests replace netcat -q flag with coreutils timeout:
the -q flag is not supported in all netcat versions
v2->v3
- move BPF_F_ADJ_ROOM_ENCAP_L3_MASK out of uapi as it has no
use in userspace
Willem de Bruijn (13):
bpf: in bpf_skb_adjust_room avoid copy in tx fast path
selftests/bpf: bpf tunnel encap test
selftests/bpf: expand bpf tunnel test with decap
selftests/bpf: expand bpf tunnel test to ipv6
selftests/bpf: extend bpf tunnel test with gre
selftests/bpf: extend bpf tunnel test with tso
bpf: add bpf_skb_adjust_room mode BPF_ADJ_ROOM_MAC
bpf: add bpf_skb_adjust_room flag BPF_F_ADJ_ROOM_FIXED_GSO
bpf: add bpf_skb_adjust_room encap flags
bpf: Sync bpf.h to tools
selftests/bpf: convert bpf tunnel test to BPF_ADJ_ROOM_MAC
selftests/bpf: convert bpf tunnel test to BPF_F_ADJ_ROOM_FIXED_GSO
selftests/bpf: convert bpf tunnel test to encap modes
include/uapi/linux/bpf.h | 29 +-
net/core/filter.c | 132 +++++++--
tools/include/uapi/linux/bpf.h | 29 +-
tools/testing/selftests/bpf/Makefile | 3 +-
tools/testing/selftests/bpf/config | 2 +
.../selftests/bpf/progs/test_tc_tunnel.c | 261 ++++++++++++++++++
tools/testing/selftests/bpf/test_tc_tunnel.sh | 178 ++++++++++++
7 files changed, 598 insertions(+), 36 deletions(-)
create mode 100644 tools/testing/selftests/bpf/progs/test_tc_tunnel.c
create mode 100755 tools/testing/selftests/bpf/test_tc_tunnel.sh
--
2.21.0.392.gf8f6787159e-goog
