Re: [PATCH bpf-next v2 04/28] libbpf: add HID program type and API

[Andrii Nakryiko]

On Fri, Mar 4, 2022 at 9:31 AM Benjamin Tissoires
<benjamin.tissoires@xxxxxxxxxx> wrote:
>
> HID-bpf program type are needing a new SEC.
> To bind a hid-bpf program, we can rely on bpf_program__attach_fd()
> so export a new function to the API.
>
> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
>
> ---
>
> changes in v2:
> - split the series by bpf/libbpf/hid/selftests and samples
> ---
>  tools/lib/bpf/libbpf.c   | 7 +++++++
>  tools/lib/bpf/libbpf.h   | 2 ++
>  tools/lib/bpf/libbpf.map | 1 +
>  3 files changed, 10 insertions(+)
>
> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
> index 81bf01d67671..356bbd3ad2c7 100644
> --- a/tools/lib/bpf/libbpf.c
> +++ b/tools/lib/bpf/libbpf.c
> @@ -8680,6 +8680,7 @@ static const struct bpf_sec_def section_defs[] = {
>         SEC_DEF("cgroup/setsockopt",    CGROUP_SOCKOPT, BPF_CGROUP_SETSOCKOPT, SEC_ATTACHABLE | SEC_SLOPPY_PFX),
>         SEC_DEF("struct_ops+",          STRUCT_OPS, 0, SEC_NONE),
>         SEC_DEF("sk_lookup",            SK_LOOKUP, BPF_SK_LOOKUP, SEC_ATTACHABLE | SEC_SLOPPY_PFX),
> +       SEC_DEF("hid/device_event",     HID, BPF_HID_DEVICE_EVENT, SEC_ATTACHABLE_OPT | SEC_SLOPPY_PFX),

no SEC_SLOPPY_PFX for any new program type, please


>  };
>
>  #define MAX_TYPE_NAME_SIZE 32
> @@ -10659,6 +10660,12 @@ static struct bpf_link *attach_iter(const struct bpf_program *prog, long cookie)
>         return bpf_program__attach_iter(prog, NULL);
>  }
>
> +struct bpf_link *
> +bpf_program__attach_hid(const struct bpf_program *prog, int hid_fd)
> +{
> +       return bpf_program__attach_fd(prog, hid_fd, 0, "hid");
> +}
> +
>  struct bpf_link *bpf_program__attach(const struct bpf_program *prog)
>  {
>         if (!prog->sec_def || !prog->sec_def->attach_fn)
> diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
> index c8d8daad212e..f677ac0a9ede 100644
> --- a/tools/lib/bpf/libbpf.h
> +++ b/tools/lib/bpf/libbpf.h
> @@ -529,6 +529,8 @@ struct bpf_iter_attach_opts {
>  LIBBPF_API struct bpf_link *
>  bpf_program__attach_iter(const struct bpf_program *prog,
>                          const struct bpf_iter_attach_opts *opts);
> +LIBBPF_API struct bpf_link *
> +bpf_program__attach_hid(const struct bpf_program *prog, int hid_fd);
>
>  /*
>   * Libbpf allows callers to adjust BPF programs before being loaded
> diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
> index 47e70c9058d9..fdc6fa743953 100644
> --- a/tools/lib/bpf/libbpf.map
> +++ b/tools/lib/bpf/libbpf.map
> @@ -424,6 +424,7 @@ LIBBPF_0.6.0 {
>  LIBBPF_0.7.0 {
>         global:
>                 bpf_btf_load;
> +               bpf_program__attach_hid;

should go into 0.8.0

>                 bpf_program__expected_attach_type;
>                 bpf_program__log_buf;
>                 bpf_program__log_level;
> --
> 2.35.1
>