One of our internal services started to use sk_msg program and currently
it used existing prog attach/detach2 as demonstrated in selftests.
But attach/detach of all other bpf programs are based on bpf_link.
Consistent attach/detach APIs for all programs will make things easy to
undersand and less error prone. So this patch added bpf_link
support for BPF_PROG_TYPE_SK_MSG. Based on comments from
previous RFC patch, I added BPF_PROG_TYPE_SK_SKB support as well
as both program types have similar treatment w.r.t. bpf_link
handling.
For the patch series, patch 1 added kernel support. Patch 2
added libbpf support. Patch 3 added bpftool support and
patches 4/5 added some new tests.
Changelogs:
v5 -> v6:
- resolve libbpf conflict due to recent upstream change.
- add a bpf_link_create() test.
- some code refactoring for better code quality.
v4 -> v5:
- increase scope of mutex protection in link_release.
- remove previous-leftover entry in libbpf.map.
- make some code changes for better understanding.
v3 -> v4:
- use a single mutex lock to protect both attach/detach/update
and release/fill_info/show_fdinfo.
- simplify code for sock_map_link_lookup().
- fix a few bugs.
- add more tests.
v2 -> v3:
- consolidate link types of sk_msg and sk_skb to
a single link type BPF_PROG_TYPE_SOCKMAP.
- fix bpf_link lifecycle issue. in v2, after bpf_link
is attached, a subsequent prog_attach could change
that bpf_link. this patch makes bpf_link having
correct behavior such that it won't go away facing
other prog/link attach for the same map and the same
attach type.
Yonghong Song (5):
bpf: Add bpf_link support for sk_msg and sk_skb progs
libbpf: Add bpf_link support for BPF_PROG_TYPE_SOCKMAP
bpftool: Add link dump support for BPF_LINK_TYPE_SOCKMAP
selftests/bpf: Refactor out helper functions for a few tests
selftests/bpf: Add some tests with new bpf_program__attach_sockmap()
APIs
include/linux/bpf.h | 6 +
include/linux/skmsg.h | 4 +
include/uapi/linux/bpf.h | 5 +
kernel/bpf/syscall.c | 4 +
net/core/sock_map.c | 261 ++++++++++++++++--
tools/bpf/bpftool/link.c | 9 +
tools/include/uapi/linux/bpf.h | 5 +
tools/lib/bpf/libbpf.c | 7 +
tools/lib/bpf/libbpf.h | 2 +
tools/lib/bpf/libbpf.map | 1 +
.../selftests/bpf/prog_tests/sockmap_basic.c | 171 +++++++++++-
.../selftests/bpf/prog_tests/sockmap_listen.c | 38 +++
.../bpf/progs/test_skmsg_load_helpers.c | 27 +-
.../bpf/progs/test_sockmap_pass_prog.c | 17 +-
.../progs/test_sockmap_skb_verdict_attach.c | 2 +-
15 files changed, 524 insertions(+), 35 deletions(-)
--
2.43.0
