On Fri, Aug 9, 2019 at 6:35 AM Daniel T. Lee <danieltim...@gmail.com> wrote:
>
> By this commit, using `bpftool net detach`, the attached XDP prog can
> be detached. Detaching the BPF prog will be done through libbpf
> 'bpf_set_link_xdp_fd' with the progfd set to -1.
>
> Signed-off-by: Daniel T. Lee <danieltim...@gmail.com>
> ---
> tools/bpf/bpftool/net.c | 42 ++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 41 insertions(+), 1 deletion(-)
>
> diff --git a/tools/bpf/bpftool/net.c b/tools/bpf/bpftool/net.c
> index 74cc346c36cd..ef1e576c6dba 100644
> --- a/tools/bpf/bpftool/net.c
> +++ b/tools/bpf/bpftool/net.c
> @@ -343,6 +343,43 @@ static int do_attach(int argc, char **argv)
> return 0;
> }
>
> +static int do_detach(int argc, char **argv)
> +{
> + enum net_attach_type attach_type;
> + int progfd, ifindex, err = 0;
> +
> + /* parse detach args */
> + if (!REQ_ARGS(3))
> + return -EINVAL;
> +
> + attach_type = parse_attach_type(*argv);
> + if (attach_type == net_attach_type_size) {
> + p_err("invalid net attach/detach type: %s", *argv);
> + return -EINVAL;
> + }
> + NEXT_ARG();
> +
> + ifindex = net_parse_dev(&argc, &argv);
> + if (ifindex < 1)
> + return -EINVAL;
> +
> + /* detach xdp prog */
> + progfd = -1;
> + if (is_prefix("xdp", attach_type_strings[attach_type]))
> + err = do_attach_detach_xdp(progfd, attach_type, ifindex,
> NULL);
> +
> + if (err < 0) {
> + p_err("interface %s detach failed: %s",
> + attach_type_strings[attach_type], strerror(errno));
> + return err;
> + }
Similar to previous patch, here we should use "strerror(-err)".
With this fixed, you can add my ack:
Acked-by: Yonghong Song <y...@fb.com>
> +
> + if (json_output)
> + jsonw_null(json_wtr);
> +
> + return 0;
> +}
> +
[...]
