Re: [PATCH bpf v2] bpf: Update bpf_{g,s}etsockopt() documentation

[Daniel Borkmann]

On 11/18/22 9:18 AM, Ji Rongfeng wrote:
> * append missing optnames to the end
> * simplify bpf_getsockopt()'s doc
>
> Signed-off-by: Ji Rongfeng <SikoJobs@xxxxxxxxxxx>
> ---
>   include/uapi/linux/bpf.h       | 20 ++++++++++++--------
>   tools/include/uapi/linux/bpf.h | 20 ++++++++++++--------
>   2 files changed, 24 insertions(+), 16 deletions(-)
>
> diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
> index 51b9aa640ad2..14f29d95ea71 100644
> --- a/include/uapi/linux/bpf.h
> +++ b/include/uapi/linux/bpf.h
> @@ -2576,14 +2576,19 @@ union bpf_attr {
>    * 		* **SOL_SOCKET**, which supports the following *optname*\ s:
>    * 		  **SO_RCVBUF**, **SO_SNDBUF**, **SO_MAX_PACING_RATE**,
>    * 		  **SO_PRIORITY**, **SO_RCVLOWAT**, **SO_MARK**,
> - * 		  **SO_BINDTODEVICE**, **SO_KEEPALIVE**.
> + * 		  **SO_BINDTODEVICE**, **SO_KEEPALIVE**, **SO_REUSEADDR**,
> + * 		  **SO_REUSEPORT**, **SO_BINDTOIFINDEX**, **SO_TXREHASH**.
>    * 		* **IPPROTO_TCP**, which supports the following *optname*\ s:
>    * 		  **TCP_CONGESTION**, **TCP_BPF_IW**,
>    * 		  **TCP_BPF_SNDCWND_CLAMP**, **TCP_SAVE_SYN**,
>    * 		  **TCP_KEEPIDLE**, **TCP_KEEPINTVL**, **TCP_KEEPCNT**,
> - *		  **TCP_SYNCNT**, **TCP_USER_TIMEOUT**, **TCP_NOTSENT_LOWAT**.
> + * 		  **TCP_SYNCNT**, **TCP_USER_TIMEOUT**, **TCP_NOTSENT_LOWAT**,
> + * 		  **TCP_NODELAY**, **TCP_MAXSEG**, **TCP_WINDOW_CLAMP**,
> + * 		  **TCP_THIN_LINEAR_TIMEOUTS**, **TCP_BPF_DELACK_MAX**,
> + * 		  **TCP_BPF_RTO_MIN**.
>    * 		* **IPPROTO_IP**, which supports *optname* **IP_TOS**.
> - * 		* **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**.
> + * 		* **IPPROTO_IPV6**, which supports the following *optname*\ s:
> + * 		  **IPV6_TCLASS**, **IPV6_AUTOFLOWLABEL**.
>    * 	Return
>    * 		0 on success, or a negative error in case of failure.
>    *
> @@ -2800,12 +2805,11 @@ union bpf_attr {
>    * 		  and **BPF_CGROUP_INET6_CONNECT**.
>    *
>    * 		This helper actually implements a subset of **getsockopt()**.
> - * 		It supports the following *level*\ s:
> + * 		It supports the same set of *optname*\ s that supported by

nit: that is supported by

> + * 		**bpf_setsockopt**\ () helper with a few exceptions:
>    *
> - * 		* **IPPROTO_TCP**, which supports *optname*
> - * 		  **TCP_CONGESTION**.
> - * 		* **IPPROTO_IP**, which supports *optname* **IP_TOS**.
> - * 		* **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**.
> + * 		* **bpf_setsockopt**\ () helper only: **TCP_BPF_***.
> + * 		* **bpf_getsockopt**\ () helper only: **TCP_SAVED_SYNC**.

I think from a user PoV the above is a bit hard to follow, maybe take Martin's
earlier feedback into account and add a proper sentence; it will be much easier
to understand.

>    * 	Return
>    * 		0 on success, or a negative error in case of failure.
>    *
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