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

[Song Liu]

> On Mar 7, 2022, at 5:30 PM, Andrii Nakryiko <andrii.nakryiko@xxxxxxxxx> wrote:
> 
> 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

Ah, I missed this one. 

btw, bpf_xdp_attach and buddies should also go into 0.8.0, no? 

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