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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 EA18FC11F67 for ; Mon, 12 Jul 2021 17:38:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D26F96120A for ; Mon, 12 Jul 2021 17:38:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235690AbhGLRlE (ORCPT ); Mon, 12 Jul 2021 13:41:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43978 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233870AbhGLRlD (ORCPT ); Mon, 12 Jul 2021 13:41:03 -0400 Received: from mail-pg1-x52a.google.com (mail-pg1-x52a.google.com [IPv6:2607:f8b0:4864:20::52a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E89B7C0613DD; Mon, 12 Jul 2021 10:38:13 -0700 (PDT) Received: by mail-pg1-x52a.google.com with SMTP id d12so18997726pgd.9; Mon, 12 Jul 2021 10:38:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=ZD1hOKzyikLBWTW4ZoPnyvY2gKEeXNcSLsw+d9zA4VQ=; b=nKHhlhdRHNxftODTOCIkDlgaV6FA5fmf8BPcGt8VoG1sHRp41AUiaAqZrTKrN+wDc2 dFPejf1KWPe1YoKioeEl+c+1INkftKkWi2TlhUw79cATJS4+HP+ysPWQmEpGLCtpSVs3 bbfEzys5m6DB/I0V6hCsrNqcq0gDk3LkMDI68WrJEWKg6kTjDytOKdUh+syYbamI0JLE 6Q7Msh3m0WLkXVKJc5W3HVgPi0cHp4nZ7iTd24jbTEsR8dveHkCx7GgBkta51kUqYuOY zdsi3yzFFNyIyOQ3CYmNIDAWygopvUPwHljJ5OT7D6617USMbYpY+iCHHDHvcZMIc7bm 1JQw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=ZD1hOKzyikLBWTW4ZoPnyvY2gKEeXNcSLsw+d9zA4VQ=; b=qKGciI9RC7gtFpTbtKLDf9P+eDP2WrmNwgMG29sYgbKPP770J3oamCPk1ztsKdnOVJ v6AYsSccj6ZLbb3o+JVbbHVojtN/e+a/wQRjx9QzBX+8ZTSCjDjrRKidqFwtoj4o9q9Y LIUgrZII9XODZWDHXiPzLgF4WgAJkxECnYlMfshUyqtpeNHQ59R8WOmlLFgkmG+0lgOj yzys9kC1/ccZQWVBZRqA3jJ3AkWicDxBK0mh+jRRVOnIEGxZEP6boCvd1+pPwILEb6vQ OjexRf5Qj53DNrp4WkTkMcwh1E27JYuv+2yjV247ePLikzQvQndNCHhfZavb2r+UIHYK Ryyw== X-Gm-Message-State: AOAM5326cByj6SndWNDbD8uET/VQ74Jp0ODMqP8eB00u8bgAW6IVOcjZ klfmCaB5lsi0xAWmPSooikI= X-Google-Smtp-Source: ABdhPJx00ULwX/fYl6jygcwepHAx93W0Ysg94pOdMnslRbsL1k1j52m8HHuZUZMkisXl8sJIgfaw4A== X-Received: by 2002:aa7:8707:0:b029:306:7e78:ee7a with SMTP id b7-20020aa787070000b02903067e78ee7amr169703pfo.29.1626111493506; Mon, 12 Jul 2021 10:38:13 -0700 (PDT) Received: from BALT-UROY.maxlinear.com ([115.187.60.212]) by smtp.gmail.com with ESMTPSA id z26sm16851491pfr.31.2021.07.12.10.38.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 12 Jul 2021 10:38:13 -0700 (PDT) From: "Roy, UjjaL" To: Song Liu , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , "David S . Miller" , Jakub Kicinski , Jonathan Corbet , Paul Walmsley , Palmer Dabbelt , Albert Ou , Nathan Chancellor , Nick Desaulniers Cc: Networking , BPF , Linux Doc Mailing List , open list , linux-riscv@lists.infradead.org, clang-built-linux@googlegroups.com Subject: [PATCH v2 bpf-nxt] Documentation/bpf: Add heading and example for extensions in filter.rst Date: Mon, 12 Jul 2021 23:07:23 +0530 Message-Id: <20210712173723.1597-1-royujjal@gmail.com> X-Mailer: git-send-email 2.31.1.windows.1 In-Reply-To: "Roy, UjjaL" References: "Roy, UjjaL" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [1] https://www.kernel.org/doc/html/latest/bpf/ Add new heading for extensions to make it more readable. Also, add one more example of filtering interface index for better understanding. Signed-off-by: Roy, UjjaL Acked-by: Song Liu --- Documentation/networking/filter.rst | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) diff --git a/Documentation/networking/filter.rst b/Documentation/networking/filter.rst index 3e2221f4abe4..5f13905b12e0 100644 --- a/Documentation/networking/filter.rst +++ b/Documentation/networking/filter.rst @@ -320,13 +320,6 @@ Examples for low-level BPF: ret #-1 drop: ret #0 -**(Accelerated) VLAN w/ id 10**:: - - ld vlan_tci - jneq #10, drop - ret #-1 - drop: ret #0 - **icmp random packet sampling, 1 in 4**:: ldh [12] @@ -358,6 +351,22 @@ Examples for low-level BPF: bad: ret #0 /* SECCOMP_RET_KILL_THREAD */ good: ret #0x7fff0000 /* SECCOMP_RET_ALLOW */ +Examples for low-level BPF extension: + +**Packet for interface index 13**:: + + ld ifidx + jneq #13, drop + ret #-1 + drop: ret #0 + +**(Accelerated) VLAN w/ id 10**:: + + ld vlan_tci + jneq #10, drop + ret #-1 + drop: ret #0 + The above example code can be placed into a file (here called "foo"), and then be passed to the bpf_asm tool for generating opcodes, output that xt_bpf and cls_bpf understands and can directly be loaded with. Example with above -- 2.17.1