From patchwork Thu Mar 25 12:00:02 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Kumar Kartikeya Dwivedi X-Patchwork-Id: 12163901 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,USER_AGENT_GIT 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 54F97C433E1 for ; Thu, 25 Mar 2021 12:03:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3251861A2A for ; Thu, 25 Mar 2021 12:03:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230419AbhCYMCn (ORCPT ); Thu, 25 Mar 2021 08:02:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47256 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230192AbhCYMCe (ORCPT ); Thu, 25 Mar 2021 08:02:34 -0400 Received: from mail-pg1-x542.google.com (mail-pg1-x542.google.com [IPv6:2607:f8b0:4864:20::542]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C8A21C06174A; Thu, 25 Mar 2021 05:02:34 -0700 (PDT) Received: by mail-pg1-x542.google.com with SMTP id r17so1601012pgi.0; Thu, 25 Mar 2021 05:02:34 -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=NL4DiOKg00UDQaQxeDVdzlsM4CnwHYQ4poPpm4WQmLg=; b=hdaTm1dl1Z9gfZmGpJ0j5Yy2/E5R4loK5MiRH9GoQl3kyQMHqA2HtSAzIGm1c5A5Wl q9f5K7biYOXXtYcXiW3rzliG3zyUwuWO5ZsDC8A1sEoea1GnsI3iX6zblcj+JqMwBYCv ebOlFmEFy5YAuBK8yrInVv/EoUVIgUM46iqEcAHcKXsWCYmfuQy3fQNaFWFAxyn1lCMT m+XvnN03WCdTcqIXO1Yuyx6uT27R/DKc6sMQiGdy+WoK4Bi1aFW3Q+8fQvb/tSsxfQQw B3+PG8C5KjLg99/+QqjeaT/w4IsvZ3z+nOUIOHlrmZsq/mANUyRq3QzOAzcYrfq5VVkx xvOw== 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=NL4DiOKg00UDQaQxeDVdzlsM4CnwHYQ4poPpm4WQmLg=; b=Btle65Fub4ZxwkOkbUBgLGQqozEupbSnLoSosSF2J27CLrdoH69kWUw7WBiHVXkmAd k1UnkowS5zJHFGbyx9bINBbpCYxO/B7Kr6doB6njG2fARrhd4JtZGoiGQk/1SAgNiC7p QRdiES2prl45Up8Ij3th78hRPTyafrik5cmG5L/oLxR86X+2ene8gxNuyFtjoKF5ueMa 5Lnuhz1Eq7RBjXMRZNAO0HNLoP800LELYwTM21QHS26mGuGvFzL3bGpuHpEyiUiyqM0E LuLnE6hzRISMGAgAZOE5BwlZBNYNyF24OTJV8cp2ZxhHalOENnMDx0xkYAFS8Tdr7SVG 4U1A== X-Gm-Message-State: AOAM530ZLn7gC5C23t4LZ3U0+b1gTblx/BmvakaSUDUI8glqzRZOqD5f rtoQvYr4eyvp01Ne/aXEm2tLjv6sEGr+UQ== X-Google-Smtp-Source: ABdhPJyxKfmDHcC1e+UmEsp9XK3agpb2ofdq3+p29uHufxN+PA8aqHnTBlLn4DqiLtqtOAsoxFuxpw== X-Received: by 2002:a65:5289:: with SMTP id y9mr6539883pgp.447.1616673754082; Thu, 25 Mar 2021 05:02:34 -0700 (PDT) Received: from localhost ([112.79.237.176]) by smtp.gmail.com with ESMTPSA id h19sm5876594pfc.172.2021.03.25.05.02.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 25 Mar 2021 05:02:33 -0700 (PDT) From: Kumar Kartikeya Dwivedi To: bpf@vger.kernel.org Cc: brouer@redhat.com, Kumar Kartikeya Dwivedi , =?utf-8?q?Toke_H=C3=B8iland-J=C3=B8rgensen?= , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Shuah Khan , "David S. Miller" , Jakub Kicinski , Jesper Dangaard Brouer , Peter Zijlstra , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: [PATCH bpf-next 4/5] libbpf: add high level TC-BPF API Date: Thu, 25 Mar 2021 17:30:02 +0530 Message-Id: <20210325120020.236504-5-memxor@gmail.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210325120020.236504-1-memxor@gmail.com> References: <20210325120020.236504-1-memxor@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org A high level API is provided using the aforementioned routines internally, and these return a bpf_link object to the user. These are limited to just attach for now, and can be extended to change/replace if the use case arises in the future. It is also possible to call bpf_link__disconnect on the link and switch to managing the filter/action manually if the need arises. In most cases, the higher level API should suffice. Example: struct bpf_tc_cls_info info = {}; struct bpf_object *obj; struct bpf_program *p; struct bpf_link *link; __u32 index; int fd, r; obj = bpf_object_open("foo.o"); if (IS_ERR_OR_NULL(obj)) return PTR_ERR(obj); p = bpf_object__find_program_by_title(obj, "classifier"); if (IS_ERR_OR_NULL(p)) return PTR_ERR(p); DECLARE_LIBBPF_OPTS(bpf_tc_cls_opts, opts, .handle = 1); link = bpf_program__attach_tc_cls_dev(p, if_nametoindex("lo"), BPF_TC_CLSACT_INGRESS, ETH_P_IP, &opts); if (IS_ERR_OR_NULL(link)) return PTR_ERR(link); /* We want to take ownership of the filter, so we disconnect the * link and detach it on our own */ bpf_link__disconnect(link); r = bpf_tc_cls_get_info_dev(bpf_program__fd(fd), if_nametoindex("lo"), BPF_TC_CLSACT_INGRESS, ETH_P_IP, &opts, &info); if (r < 0) return r; /* We get the attach_id in the info struct, pass it to detach */ bpf_tc_cls_detach_dev(&info.id); bpf_link__destroy(link); Example: struct bpf_object *obj; struct bpf_program *p; struct bpf_link *link; __u32 index; int fd, r; obj = bpf_object_open("foo.o"); if (IS_ERR_OR_NULL(obj)) return PTR_ERR(obj); p = bpf_object__find_program_by_title(obj, "action"); if (IS_ERR_OR_NULL(p)) return PTR_ERR(p); /* A simple example that attaches a SCHED_ACT prog */ link = bpf_program__attach_tc_act(p, NULL); if (IS_ERR_OR_NULL(link)) return PTR_ERR(link); bpf_link__destroy(link); Reviewed-by: Toke Høiland-Jørgensen Signed-off-by: Kumar Kartikeya Dwivedi --- tools/lib/bpf/libbpf.c | 110 ++++++++++++++++++++++++++++++++++++++- tools/lib/bpf/libbpf.h | 15 ++++++ tools/lib/bpf/libbpf.map | 3 ++ 3 files changed, 127 insertions(+), 1 deletion(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 058b643cbcb1..cc5c200a661d 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include #include @@ -6847,7 +6848,7 @@ static int bpf_object__collect_relos(struct bpf_object *obj) for (i = 0; i < obj->nr_programs; i++) { struct bpf_program *p = &obj->programs[i]; - + if (!p->nr_reloc) continue; @@ -9443,6 +9444,10 @@ int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, struct bpf_link { int (*detach)(struct bpf_link *link); int (*destroy)(struct bpf_link *link); + union { + struct bpf_tc_cls_attach_id *tc_cls_id; + __u32 tc_act_index; + }; char *pin_path; /* NULL, if not pinned */ int fd; /* hook FD, -1 if not applicable */ bool disconnected; @@ -10199,6 +10204,109 @@ struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map) return link; } +static int bpf_link__detach_tc_cls(struct bpf_link *link) +{ + return bpf_tc_cls_detach_dev(link->tc_cls_id); +} + +static int bpf_link__destroy_tc_cls(struct bpf_link *link) +{ + zfree(&link->tc_cls_id); + return 0; +} + +struct bpf_link *bpf_program__attach_tc_cls_dev(struct bpf_program *prog, + __u32 ifindex, __u32 parent_id, + __u32 protocol, + const struct bpf_tc_cls_opts *opts) +{ + struct bpf_tc_cls_attach_id *id = NULL; + struct bpf_link *link = NULL; + char errmsg[STRERR_BUFSIZE]; + int prog_fd, err; + + prog_fd = bpf_program__fd(prog); + if (prog_fd < 0) { + pr_warn("prog '%s': can't attach before loaded\n", prog->name); + return ERR_PTR(-EINVAL); + } + + link = calloc(1, sizeof(*link)); + if (!link) + return ERR_PTR(-ENOMEM); + link->detach = &bpf_link__detach_tc_cls; + link->destroy = &bpf_link__destroy_tc_cls; + link->fd = -1; + + id = calloc(1, sizeof(*id)); + if (!id) { + err = -ENOMEM; + goto end; + } + + err = bpf_tc_cls_attach_dev(prog_fd, ifindex, parent_id, protocol, opts, id); + if (err < 0) { + pr_warn("prog '%s': failed to attach classifier: %s\n", + prog->name, + libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + goto end; + } + + link->tc_cls_id = id; + return link; + +end: + free(id); + free(link); + return ERR_PTR(err); +} + +struct bpf_link *bpf_program__attach_tc_cls_block(struct bpf_program *prog, + __u32 block_index, __u32 protocol, + const struct bpf_tc_cls_opts *opts) +{ + return bpf_program__attach_tc_cls_dev(prog, TCM_IFINDEX_MAGIC_BLOCK, block_index, + protocol, opts); +} + +static int bpf_link__detach_tc_act(struct bpf_link *link) +{ + return bpf_tc_act_detach(link->tc_act_index); +} + +struct bpf_link *bpf_program__attach_tc_act(struct bpf_program *prog, + const struct bpf_tc_act_opts *opts) +{ + struct bpf_link *link = NULL; + char errmsg[STRERR_BUFSIZE]; + int prog_fd, err; + + prog_fd = bpf_program__fd(prog); + if (prog_fd < 0) { + pr_warn("prog '%s': can't attach before loading\n", prog->name); + return ERR_PTR(-EINVAL); + } + + link = calloc(1, sizeof(*link)); + if (!link) + return ERR_PTR(-ENOMEM); + link->detach = &bpf_link__detach_tc_act; + link->fd = -1; + + err = bpf_tc_act_attach(prog_fd, opts, &link->tc_act_index); + if (err < 0) { + pr_warn("prog '%s': failed to attach action: %s\n", prog->name, + libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + goto end; + } + + return link; + +end: + free(link); + return ERR_PTR(err); +} + enum bpf_perf_event_ret bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size, void **copy_mem, size_t *copy_size, diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 63baef6045b1..e33720d0b672 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -268,6 +268,21 @@ LIBBPF_API struct bpf_link * bpf_program__attach_freplace(struct bpf_program *prog, int target_fd, const char *attach_func_name); +struct bpf_tc_cls_opts; +struct bpf_tc_act_opts; + +LIBBPF_API struct bpf_link * +bpf_program__attach_tc_cls_dev(struct bpf_program *prog, __u32 ifindex, + __u32 parent_id, __u32 protocol, + const struct bpf_tc_cls_opts *opts); +LIBBPF_API struct bpf_link * +bpf_program__attach_tc_cls_block(struct bpf_program *prog, __u32 block_index, + __u32 protocol, + const struct bpf_tc_cls_opts *opts); +LIBBPF_API struct bpf_link * +bpf_program__attach_tc_act(struct bpf_program *prog, + const struct bpf_tc_act_opts *opts); + struct bpf_map; LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map); diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index 72022b45a8b9..2e1390e4ebf0 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -373,4 +373,7 @@ LIBBPF_0.4.0 { bpf_tc_cls_replace_dev; bpf_tc_cls_get_info_dev; bpf_tc_cls_get_info_block; + bpf_program__attach_tc_cls_dev; + bpf_program__attach_tc_cls_block; + bpf_program__attach_tc_act; } LIBBPF_0.3.0;