From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6F727C282C8 for ; Mon, 28 Jan 2019 21:08:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 365D22148E for ; Mon, 28 Jan 2019 21:08:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="DJIcOCOB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727812AbfA1VIC (ORCPT ); Mon, 28 Jan 2019 16:08:02 -0500 Received: from mail-io1-f67.google.com ([209.85.166.67]:35037 "EHLO mail-io1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726859AbfA1VIB (ORCPT ); Mon, 28 Jan 2019 16:08:01 -0500 Received: by mail-io1-f67.google.com with SMTP id f4so14756292ion.2 for ; Mon, 28 Jan 2019 13:08:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=/f+WFca8iVkIdRF2kV8dGxA+dLrtzj0o9w50M7Xvwlk=; b=DJIcOCOBHUTBpzHlcZCUTWJ0vKFC6R4ReTNP2/2OXoLD5n4YwdMYtqO+DkBD/9QGy4 tGWdR2rm+pE9yh0Kxcqu2l2akBaEvRVyP5wdnF2ewcLZQs9XwIa82+ADyUm5ZR9Y25jm RMY9IQq+qhmN6RNh8Ph3DSrhV+LHBYRiYNajXN95jMJ7GkRoTXGwf//r8pyUvSbmNYNi 6YbpyAMh+VCGvFRwxZofDwILK4g0q8fhZ3nAntD2dlnxepdz2qo7f/VZU7HYEOsWazTX pvIyLFG3Ql0P9IsRRweHY48KQAR29VhTiJ6SIa1zCyRNh1vPPXUTP/lxYQhvyFHcc5X3 O0QQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=/f+WFca8iVkIdRF2kV8dGxA+dLrtzj0o9w50M7Xvwlk=; b=dRt/z4ZXFwF3gYTw8h2t1cv5jm8jSVSibFAzFW4Yt2EWfEVw4wgtG1IzvcD79YK7VH 3+VbKKGlQN0xTlkbY5JnQ8PZbKdUMgdv4fGAoqHkJhLj+1WqE+IJmUFZCRyTm1g9yJjA +tCHo0e2iHSJvkQI4bUvMXd/hlee0xMIrkRCMJKDKfRfiRDSQlOYyTB61PlTZNNTiKjD SztQnVuaF6xKBnhwnl9oHhT6yuJCFOztjcTjzOq+FAQtOPvPCVBIHSpEypihrimqNa7s iQRTNHXOWCYBQAwotuYQo9flCLzO1gPeNfi4KsxfbrNwAMdy8ryuZTXMaQoo50W/N5na OB9g== X-Gm-Message-State: AHQUAuY3oemIidKVCNovndSqCusMxad5vOPMo7gJi7G31r60eP/cjGjo HSN4oeRMOIdDwUTyKmuTEhk= X-Google-Smtp-Source: AHgI3IYBpr97ChZveUpQKtsSA8IePU1CMozjFuP5tJUYdGaTcozcMjDDtj/o22nxaU/V9imLLWLVwA== X-Received: by 2002:a6b:8b0a:: with SMTP id n10mr13153013iod.2.1548709680778; Mon, 28 Jan 2019 13:08:00 -0800 (PST) Received: from [192.168.86.250] ([184.63.162.180]) by smtp.gmail.com with ESMTPSA id v4sm685506itv.20.2019.01.28.13.07.54 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 28 Jan 2019 13:08:00 -0800 (PST) Subject: Re: [PATCH bpf-next v4 6/7] libbpf: Add a support for getting xdp prog id on ifindex To: Maciej Fijalkowski , daniel@iogearbox.net, ast@kernel.org Cc: netdev@vger.kernel.org, jakub.kicinski@netronome.com, brouer@redhat.com References: <20190128191613.11705-1-maciejromanfijalkowski@gmail.com> <20190128191613.11705-7-maciejromanfijalkowski@gmail.com> From: John Fastabend Message-ID: Date: Mon, 28 Jan 2019 13:07:49 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <20190128191613.11705-7-maciejromanfijalkowski@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 1/28/19 11:16 AM, Maciej Fijalkowski wrote: > From: Maciej Fijalkowski > > Since we have a dedicated netlink attributes for xdp setup on a > particular interface, it is now possible to retrieve the program id that > is currently attached to the interface. The use case is targeted for > sample xdp programs, which will store the program id just after loading > bpf program onto iface. On shutdown, the sample will make sure that it > can unload the program by querying again the iface and verifying that > both program id's matches. > > Signed-off-by: Maciej Fijalkowski > Reviewed-by: Jakub Kicinski > --- small nit. > + > +int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags) > +{ > + struct xdp_id_md xdp_id = {}; > + int sock, ret; > + __u32 nl_pid; > + __u32 mask; > + > + if (flags & ~XDP_FLAGS_MASK) > + return -EINVAL; > + > + /* Check whether the single {HW,DRV,SKB} mode is set */ > + flags &= XDP_FLAGS_MODES; > + mask = flags - 1; > + if (flags && flags & mask) > + return -EINVAL; > + > + sock = libbpf_netlink_open(&nl_pid); > + if (sock < 0) > + return sock; > + > + xdp_id.ifindex = ifindex; > + xdp_id.flags = flags; > + > + ret = libbpf_nl_get_link(sock, nl_pid, get_xdp_id, &xdp_id); > + *prog_id = xdp_id.id; just a nit but should we really set prog_id from user if there is an error. Probably friendlier not to set caller data in error case. > + > + close(sock); > + return ret; > +} > + > int libbpf_nl_get_link(int sock, unsigned int nl_pid, > libbpf_dump_nlmsg_t dump_link_nlmsg, void *cookie) > { >