Re: [PATCH v4 04/10] net/socket: Break down __sys_getsockopt

From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Breno Leitao <leitao@debian.org>
Cc: sdf@google.com, axboe@kernel.dk, asml.silence@gmail.com,
	willemdebruijn.kernel@gmail.com, martin.lau@linux.dev,
	krisman@suse.de, Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Andrii Nakryiko <andrii@kernel.org>, Song Liu <song@kernel.org>,
	Yonghong Song <yonghong.song@linux.dev>,
	John Fastabend <john.fastabend@gmail.com>,
	KP Singh <kpsingh@kernel.org>, Hao Luo <haoluo@google.com>,
	Jiri Olsa <jolsa@kernel.org>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	bpf@vger.kernel.org, linux-kernel@vger.kernel.org,
	netdev@vger.kernel.org, io-uring@vger.kernel.org,
	Kuniyuki Iwashima <kuniyu@amazon.com>,
	Alexander Mikhalitsyn <alexander@mihalicyn.com>,
	Xin Long <lucien.xin@gmail.com>,
	David Howells <dhowells@redhat.com>,
	Jason Xing <kernelxing@tencent.com>
Subject: Re: [PATCH v4 04/10] net/socket: Break down __sys_getsockopt
Date: Tue, 5 Sep 2023 13:29:22 +0300	[thread overview]
Message-ID: <ZPcDAk81DAqevy43@smile.fi.intel.com> (raw)
In-Reply-To: <20230904162504.1356068-5-leitao@debian.org>

On Mon, Sep 04, 2023 at 09:24:57AM -0700, Breno Leitao wrote:
> Split __sys_getsockopt() into two functions by removing the core
> logic into a sub-function (do_sock_getsockopt()). This will avoid
> code duplication when doing the same operation in other callers, for
> instance.
> 
> do_sock_getsockopt() will be called by io_uring getsockopt() command
> operation in the following patch.
> 
> The same was done for the setsockopt pair.

...

> +	ops = READ_ONCE(sock->ops);
> +	if (level == SOL_SOCKET) {
> +		err = sk_getsockopt(sock->sk, level, optname, optval, optlen);
> +	} else if (unlikely(!ops->getsockopt)) {
> +		err = -EOPNOTSUPP;
> +	} else {
> +		if (WARN_ONCE(optval.is_kernel || optlen.is_kernel,
> +			      "Invalid argument type"))
> +			return -EOPNOTSUPP;
> +
> +		err = ops->getsockopt(sock, level, optname, optval.user,
> +				      optlen.user);
> +	}

Can be written as

	} else if (WARN_ONCE(optval.is_kernel || optlen.is_kernel,
			     "Invalid argument type"))
		return -EOPNOTSUPP;
	} else {
		err = ops->getsockopt(sock, level, optname, optval.user,
				      optlen.user);
	}

With that done, the {} are not needed anymore.

> +	if (!compat) {

	if (compat)
		return err;

> +		max_optlen = BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen);

> +		err = BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock->sk, level, optname,
> +						     optval, optlen, max_optlen,
> +						     err);

	return ... ?

> +	}
> +
> +	return err;
> +}

-- 
With Best Regards,
Andy Shevchenko