[RFC PATCH bpf-next 0/5] Add bpf_link support for sk_msg prog

[Yonghong Song <yonghong.song@linux.dev>]

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.

I marked the patch as RFC as not all functionality are covered
by tests yet, e.g. update_prog(). Maybe somebody can suggest
an existing test which I can look into.
Or maybe some other tests need to be added as well.

Yonghong Song (5):
  bpf: Add link support for sk_msg prog
  libbpf: Refactor bpf_program_attach_fd()
  libbpf: Add link support for BPF_PROG_TYPE_SK_MSG
  bpftool: Add link dump support for BPF_LINK_TYPE_SK_MSG
  selftests/bpf: Add some tests with new bpf_program__attach_sk_msg()
    API

 include/linux/bpf.h                           |  13 ++
 include/uapi/linux/bpf.h                      |   5 +
 kernel/bpf/syscall.c                          |   3 +
 net/core/skmsg.c                              | 153 ++++++++++++++++++
 net/core/sock_map.c                           |   6 +-
 tools/bpf/bpftool/link.c                      |   8 +
 tools/include/uapi/linux/bpf.h                |   5 +
 tools/lib/bpf/libbpf.c                        |  26 ++-
 tools/lib/bpf/libbpf.h                        |   3 +
 tools/lib/bpf/libbpf.map                      |   1 +
 .../selftests/bpf/prog_tests/sockmap_basic.c  |  27 ++++
 .../selftests/bpf/prog_tests/sockmap_listen.c |  38 +++++
 12 files changed, 279 insertions(+), 9 deletions(-)

-- 
2.43.0