Re: [PATCH v2 0/6] Add _opts variant for bpf_*_get_fd_by_id()

[Roberto Sassu <roberto.sassu@huaweicloud.com>]

On Fri, 2022-10-07 at 12:59 +0200, Jiri Olsa wrote:
> On Thu, Oct 06, 2022 at 01:07:30PM +0200, Roberto Sassu wrote:
> > From: Roberto Sassu <roberto.sassu@huawei.com>
> > 
> > Add the _opts variant for bpf_*_get_fd_by_id() functions, to be
> > able to
> > pass to the kernel more options, when requesting a fd of an eBPF
> > object.
> > 
> > Pass the options through a newly introduced structure,
> > bpf_get_fd_by_id_opts, which currently contains open_flags (the
> > other two
> > members are for compatibility and for padding).
> > 
> > open_flags allows the caller to request specific permissions to
> > access a
> > map (e.g. read-only). This is useful for example in the situation
> > where a
> > map is write-protected.
> > 
> > Besides patches 2-6, which introduce the new variants and the data
> > structure, patch 1 fixes the LIBBPF_1.0.0 declaration in
> > libbpf.map.
> > 
> > Changelog
> > 
> > v1:
> >  - Don't CC stable kernel mailing list for patch 1 (suggested by
> > Andrii)
> >  - Rename bpf_get_fd_opts struct to bpf_get_fd_by_id_opts
> > (suggested by
> >    Andrii)
> >  - Move declaration of _opts variants after non-opts variants
> > (suggested by
> >    Andrii)
> >  - Correctly initialize bpf_map_info, fix style issues, use map
> > from
> >    skeleton, check valid fd in the test (suggested by Andrii)
> >  - Rename libbpf_get_fd_opts test to libbpf_get_fd_by_id_opts
> > 
> > Roberto Sassu (6):
> >   libbpf: Fix LIBBPF_1.0.0 declaration in libbpf.map
> >   libbpf: Introduce bpf_get_fd_by_id_opts and
> >     bpf_map_get_fd_by_id_opts()
> >   libbpf: Introduce bpf_prog_get_fd_by_id_opts()
> >   libbpf: Introduce bpf_btf_get_fd_by_id_opts()
> >   libbpf: Introduce bpf_link_get_fd_by_id_opts()
> >   selftests/bpf: Add tests for _opts variants of
> > bpf_*_get_fd_by_id()
> 
> it's not marked, but I'm assuming this goes to bpf-next, right?

At the next possible chance would be perfect.

> anyway, lgtm
> 
> Acked-by: Jiri Olsa <jolsa@kernel.org>

Thanks

Roberto

> thanks,
> jirka
> 
> >  tools/lib/bpf/bpf.c                           | 48 +++++++++-
> >  tools/lib/bpf/bpf.h                           | 16 ++++
> >  tools/lib/bpf/libbpf.map                      |  6 +-
> >  tools/testing/selftests/bpf/DENYLIST.s390x    |  1 +
> >  .../bpf/prog_tests/libbpf_get_fd_by_id_opts.c | 87
> > +++++++++++++++++++
> >  .../bpf/progs/test_libbpf_get_fd_by_id_opts.c | 36 ++++++++
> >  6 files changed, 189 insertions(+), 5 deletions(-)
> >  create mode 100644
> > tools/testing/selftests/bpf/prog_tests/libbpf_get_fd_by_id_opts.c
> >  create mode 100644
> > tools/testing/selftests/bpf/progs/test_libbpf_get_fd_by_id_opts.c
> > 
> > -- 
> > 2.25.1
> >