Re: [PATCH 6.8 119/715] libbpf: Add bpf_token_create() API

Jiri Slaby
2024-03-25T05:40:49Z

On 24. 03. 24, 23:24, Sasha Levin wrote:
> From: Andrii Nakryiko <andrii@kernel.org>
>
> [ Upstream commit 639ecd7d6247c48a0175f5b458b648f5d4b6dc34 ]
>
> Add low-level wrapper API for BPF_TOKEN_CREATE command in bpf() syscall.
>
> Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
> Link: https://lore.kernel.org/bpf/20240124022127.2379740-13-andrii@kernel.org
> Stable-dep-of: c81a8ab196b5 ("libbpf: Add btf__new_split() API that was declared but not implemented")
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
> tools/lib/bpf/bpf.c | 17 +++++++++++++++++
> tools/lib/bpf/bpf.h | 24 ++++++++++++++++++++++++
> tools/lib/bpf/libbpf.map | 1 +
> 3 files changed, 42 insertions(+)
>
> diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
> index 9dc9625651dcf..d4019928a8646 100644
> --- a/tools/lib/bpf/bpf.c
> +++ b/tools/lib/bpf/bpf.c
> @@ -1287,3 +1287,20 @@ int bpf_prog_bind_map(int prog_fd, int map_fd,
> ret = sys_bpf(BPF_PROG_BIND_MAP, &attr, attr_sz);
> return libbpf_err_errno(ret);
> }
> +
> +int bpf_token_create(int bpffs_fd, struct bpf_token_create_opts *opts)
> +{
> + const size_t attr_sz = offsetofend(union bpf_attr, token_create);
> + union bpf_attr attr;
> + int fd;
> +
> + if (!OPTS_VALID(opts, bpf_token_create_opts))
> + return libbpf_err(-EINVAL);
> +
> + memset(&attr, 0, attr_sz);
> + attr.token_create.bpffs_fd = bpffs_fd;
> + attr.token_create.flags = OPTS_GET(opts, flags, 0);

With openSUSE config [1], I see:
bpf.c:1293:60: error: ‘union bpf_attr’ has no member named
‘token_create’; did you mean ‘iter_create’?
bpf.c:1293:60: error: ‘union bpf_attr’ has no member named
‘token_create’; did you mean ‘iter_create’?
bpf.c:1301:14: error: ‘union bpf_attr’ has no member named
‘token_create’; did you mean ‘iter_create’?
bpf.c:1302:14: error: ‘union bpf_attr’ has no member named
‘token_create’; did you mean ‘iter_create’?

[1]
https://github.com/openSUSE/kernel-source/blob/master/config/x86_64/default

> + fd = sys_bpf_fd(BPF_TOKEN_CREATE, &attr, attr_sz);

And:

bpf.c:1304:25: error: ‘BPF_TOKEN_CREATE’ undeclared (first use in this
function); did you mean ‘BPF_ITER_CREATE’?

They are added by:
commit 35f96de04127d332a5c5e8a155d31f452f88c76d
Author: Andrii Nakryiko <andrii@kernel.org>
Date: Tue Jan 23 18:21:00 2024 -0800

bpf: Introduce BPF token object

But if you should take it or drop this all, I don't know...

thanks,
--
js
suse labs