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=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,UNWANTED_LANGUAGE_BODY,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 9771FC3A59F for ; Mon, 26 Aug 2019 16:25:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 621482080C for ; Mon, 26 Aug 2019 16:25:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="HEzwBbLh" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732128AbfHZQZ1 (ORCPT ); Mon, 26 Aug 2019 12:25:27 -0400 Received: from mail-pg1-f178.google.com ([209.85.215.178]:33452 "EHLO mail-pg1-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729338AbfHZQZ1 (ORCPT ); Mon, 26 Aug 2019 12:25:27 -0400 Received: by mail-pg1-f178.google.com with SMTP id n190so10929648pgn.0 for ; Mon, 26 Aug 2019 09:25:26 -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:mime-version :content-transfer-encoding; bh=8MBb1j9PrRL5Q32BVVyjoPIVxdK/pWPaxnpIeQ11yLA=; b=HEzwBbLhezirzF5XIsphQOzd8b81Dzrpzziu+YL61hEZ8ofvgViGQfhu2SvavMBAsQ 3mlTkVr5QKIpjN6hZ34QZRv+oQfs11XR7K/VqllN6mQLPs34lYA3YNQWUJ74Eb4Pnbqe nYKFRLWcOmHejRNJZTX+6DvMjC69YESYsAwpqn0r8QB1EUtmeC3svLEgwoO5pQjTdSAM v4hWrMwzslK5av8DnKH3/DLxfDsEXGvMI6X1bji0NSdEaJu9gpNznjFH7qAeRgoysVt9 qvsWb5f0O3tjN+rZoeXcy5fC5LdP22gUkMt9vrJWhzicAyHg6YQBCrJXUfGyfi/oYE/+ Hfdg== 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:mime-version :content-transfer-encoding; bh=8MBb1j9PrRL5Q32BVVyjoPIVxdK/pWPaxnpIeQ11yLA=; b=f7qpZop1IY+EGi0ah+Q/W25AREiVFFvz2ZWSVPV4Q1rBxDOCaC+87xkOBfUZyFOjaP U8fwGWFVYdGVOXJeqjEKQpQwH+ZfLmpXGgct7YzLMJMiC0+SDi4HZiFAOkeZYL20I5vB 3uiBXHMnonaeVt/RVzvYf96iWIKYOfjt61ccbC9FTJhppnQOxiDeDCArF4ydC733iY64 QRbEfLPLwS5Avng9CnMHATvWBgc4nHHQZ1kAj+Ns6x2rrhHWJpcSmaj1YuzgOMExktBn 4FzlsGx9qN2+IJ0x6HJ/OOZhmXogw3Ymdp2Afj3t+XFJR5K+fo4SHo5X6ypBdREKSuFP QQGg== X-Gm-Message-State: APjAAAUx1A5c6bjRDZTDopqIKgkjn54rKw7bN93mzdLUJcUrKcp0fSl4 Bb09A4Pg8Zgq8UXKDOnDD0IwAQUZsA== X-Google-Smtp-Source: APXvYqwAmOT8cUie7RMFelO3k9R8iOAihP31EpU7Aa8ns7dMPehZZUpJv1b+1aKbGG7gkdwRqK3unw== X-Received: by 2002:a62:f94a:: with SMTP id g10mr4541881pfm.167.1566836726180; Mon, 26 Aug 2019 09:25:26 -0700 (PDT) Received: from localhost.localdomain ([219.255.158.171]) by smtp.gmail.com with ESMTPSA id g11sm10825700pgu.11.2019.08.26.09.25.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 26 Aug 2019 09:25:24 -0700 (PDT) From: "Daniel T. Lee" To: Daniel Borkmann , Alexei Starovoitov Cc: netdev@vger.kernel.org Subject: [bpf-next, v2] samples: bpf: add max_pckt_size option at xdp_adjust_tail Date: Tue, 27 Aug 2019 01:25:17 +0900 Message-Id: <20190826162517.8082-1-danieltimlee@gmail.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Currently, at xdp_adjust_tail_kern.c, MAX_PCKT_SIZE is limited to 600. To make this size flexible, a new map 'pcktsz' is added. By updating new packet size to this map from the userland, xdp_adjust_tail_kern.o will use this value as a new max_pckt_size. If no '-P ' option is used, the size of maximum packet will be 600 as a default. Signed-off-by: Daniel T. Lee --- Changes in v2: - Change the helper to fetch map from 'bpf_map__next' to 'bpf_object__find_map_fd_by_name'. samples/bpf/xdp_adjust_tail_kern.c | 23 +++++++++++++++++++---- samples/bpf/xdp_adjust_tail_user.c | 27 +++++++++++++++++++++------ 2 files changed, 40 insertions(+), 10 deletions(-) diff --git a/samples/bpf/xdp_adjust_tail_kern.c b/samples/bpf/xdp_adjust_tail_kern.c index 411fdb21f8bc..d6d84ffe6a7a 100644 --- a/samples/bpf/xdp_adjust_tail_kern.c +++ b/samples/bpf/xdp_adjust_tail_kern.c @@ -25,6 +25,13 @@ #define ICMP_TOOBIG_SIZE 98 #define ICMP_TOOBIG_PAYLOAD_SIZE 92 +struct bpf_map_def SEC("maps") pcktsz = { + .type = BPF_MAP_TYPE_ARRAY, + .key_size = sizeof(__u32), + .value_size = sizeof(__u32), + .max_entries = 1, +}; + struct bpf_map_def SEC("maps") icmpcnt = { .type = BPF_MAP_TYPE_ARRAY, .key_size = sizeof(__u32), @@ -64,7 +71,8 @@ static __always_inline void ipv4_csum(void *data_start, int data_size, *csum = csum_fold_helper(*csum); } -static __always_inline int send_icmp4_too_big(struct xdp_md *xdp) +static __always_inline int send_icmp4_too_big(struct xdp_md *xdp, + __u32 max_pckt_size) { int headroom = (int)sizeof(struct iphdr) + (int)sizeof(struct icmphdr); @@ -92,7 +100,7 @@ static __always_inline int send_icmp4_too_big(struct xdp_md *xdp) orig_iph = data + off; icmp_hdr->type = ICMP_DEST_UNREACH; icmp_hdr->code = ICMP_FRAG_NEEDED; - icmp_hdr->un.frag.mtu = htons(MAX_PCKT_SIZE-sizeof(struct ethhdr)); + icmp_hdr->un.frag.mtu = htons(max_pckt_size - sizeof(struct ethhdr)); icmp_hdr->checksum = 0; ipv4_csum(icmp_hdr, ICMP_TOOBIG_PAYLOAD_SIZE, &csum); icmp_hdr->checksum = csum; @@ -118,14 +126,21 @@ static __always_inline int handle_ipv4(struct xdp_md *xdp) { void *data_end = (void *)(long)xdp->data_end; void *data = (void *)(long)xdp->data; + __u32 max_pckt_size = MAX_PCKT_SIZE; + __u32 *pckt_sz; + __u32 key = 0; int pckt_size = data_end - data; int offset; - if (pckt_size > MAX_PCKT_SIZE) { + pckt_sz = bpf_map_lookup_elem(&pcktsz, &key); + if (pckt_sz && *pckt_sz) + max_pckt_size = *pckt_sz; + + if (pckt_size > max_pckt_size) { offset = pckt_size - ICMP_TOOBIG_SIZE; if (bpf_xdp_adjust_tail(xdp, 0 - offset)) return XDP_PASS; - return send_icmp4_too_big(xdp); + return send_icmp4_too_big(xdp, max_pckt_size); } return XDP_PASS; } diff --git a/samples/bpf/xdp_adjust_tail_user.c b/samples/bpf/xdp_adjust_tail_user.c index a3596b617c4c..29ade7caf841 100644 --- a/samples/bpf/xdp_adjust_tail_user.c +++ b/samples/bpf/xdp_adjust_tail_user.c @@ -72,6 +72,7 @@ static void usage(const char *cmd) printf("Usage: %s [...]\n", cmd); printf(" -i Interface\n"); printf(" -T Default: 0 (forever)\n"); + printf(" -P Default: 600\n"); printf(" -S use skb-mode\n"); printf(" -N enforce native mode\n"); printf(" -F force loading prog\n"); @@ -85,13 +86,14 @@ int main(int argc, char **argv) .prog_type = BPF_PROG_TYPE_XDP, }; unsigned char opt_flags[256] = {}; - const char *optstr = "i:T:SNFh"; + const char *optstr = "i:T:P:SNFh"; struct bpf_prog_info info = {}; __u32 info_len = sizeof(info); + __u32 max_pckt_size = 0; + __u32 key = 0; unsigned int kill_after_s = 0; int i, prog_fd, map_fd, opt; struct bpf_object *obj; - struct bpf_map *map; char filename[256]; int err; @@ -110,6 +112,9 @@ int main(int argc, char **argv) case 'T': kill_after_s = atoi(optarg); break; + case 'P': + max_pckt_size = atoi(optarg); + break; case 'S': xdp_flags |= XDP_FLAGS_SKB_MODE; break; @@ -150,12 +155,22 @@ int main(int argc, char **argv) if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd)) return 1; - map = bpf_map__next(NULL, obj); - if (!map) { - printf("finding a map in obj file failed\n"); + /* update pcktsz map */ + if (max_pckt_size) { + map_fd = bpf_object__find_map_fd_by_name(obj, "pcktsz"); + if (!map_fd) { + printf("finding a pcktsz map in obj file failed\n"); + return 1; + } + bpf_map_update_elem(map_fd, &key, &max_pckt_size, BPF_ANY); + } + + /* fetch icmpcnt map */ + map_fd = bpf_object__find_map_fd_by_name(obj, "icmpcnt"); + if (!map_fd) { + printf("finding a icmpcnt map in obj file failed\n"); return 1; } - map_fd = bpf_map__fd(map); if (!prog_fd) { printf("load_bpf_file: %s\n", strerror(errno)); -- 2.20.1