From patchwork Tue Oct 31 22:08:11 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stephen Hemminger X-Patchwork-Id: 133683 X-Patchwork-Delegate: ferruh.yigit@amd.com Return-Path: X-Original-To: patchwork@inbox.dpdk.org Delivered-To: patchwork@inbox.dpdk.org Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 5FBFA43256; Tue, 31 Oct 2023 23:09:33 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id E42E0410E3; Tue, 31 Oct 2023 23:09:27 +0100 (CET) Received: from mail-oi1-f173.google.com (mail-oi1-f173.google.com [209.85.167.173]) by mails.dpdk.org (Postfix) with ESMTP id 432FD40285 for ; Tue, 31 Oct 2023 23:09:26 +0100 (CET) Received: by mail-oi1-f173.google.com with SMTP id 5614622812f47-3b2f4a5ccebso3990058b6e.3 for ; Tue, 31 Oct 2023 15:09:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20230601.gappssmtp.com; s=20230601; t=1698790165; x=1699394965; darn=dpdk.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=fmtwgbLnLLkSqRMQrXEkXU74D72XtWj7XU4moEIg55A=; b=gHiikkTDJKHH6fsPgz5nzglkt+NQa6Z0nAphpu3/DuI0ciYJ7w6AodoJM4RUDo55Kt zURzxGx2xYVnd25ihCR8pK8RYUZee9bXJjcsJZnsRjPqjQJZTAXXxVfu7Ze8izrMZkZh XhJP513ZNRhP2HWEP0XXfwtm0q+FHlMaWtzmMB0E0DM4Ufe8ms+J8H+HeTyhGEOCN5cQ EPjegpD1ky3mIG2kp8Aq9VuD6l2AahJTtoi93J7L/5sUFLU62LOGlMEzrHe+hEGBReLP w+va2vkYq7t7vIdVZUI91M8V6Ashe2H15Otx6UVVf/wg8joG4KjBhSBjZ+KA4bNxBUSn BdBw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1698790165; x=1699394965; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=fmtwgbLnLLkSqRMQrXEkXU74D72XtWj7XU4moEIg55A=; b=MHS9TgrH+dzTGjK/oPqRZluPSfA339RX6TtXZwbc685HZq35iMBb/6r9s+trIUqD+h umzgjlyLdHSsaI6ks+Ufl8LQh78zgfoKlnE2px7FTSYJmwFNMxliL1nhs+Q7PG6e7QK4 0n+sEHFFyjhwwxQjN1VEgmjuFLMrIBPPzw4wj48kSjjRQdEQhTZT1S0J39u6ciYvKgBr jMvDR/JAiYCvx6Z1nK1EsT9fK8JUwrLVZaflsm/h4JhaNIIxyLt1rWrfmYu+zWJp3MKp pCVZnHM5ExpK1ZPh2TDxB95nlDSO1O29ekVbILenasFAKeDqJShYwWBviArc5csJFpep BtXw== X-Gm-Message-State: AOJu0YyBSC2iknmmlu+gd06ULKQ0PDKhtKWc3KIzJXAoGs6usUYg64Fp 1wiKMA/9vxpCoZ/gvKzO9PckZWBT+CYlyzWZTNqwsNIT X-Google-Smtp-Source: AGHT+IH++m5FOYzVakV8zJlMCkrWe1Hg/y8Ce4lN8j60UFvvKGQAphfoEEofSlJQHsxKcdr5V7er2Q== X-Received: by 2002:a54:4703:0:b0:3ad:c262:7a0a with SMTP id k3-20020a544703000000b003adc2627a0amr13703176oik.55.1698790165095; Tue, 31 Oct 2023 15:09:25 -0700 (PDT) Received: from fedora.. ([38.142.2.14]) by smtp.gmail.com with ESMTPSA id ey2-20020a056a0038c200b0065a1b05193asm100750pfb.185.2023.10.31.15.09.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 31 Oct 2023 15:09:24 -0700 (PDT) From: Stephen Hemminger To: dev@dpdk.org Cc: Stephen Hemminger Subject: [PATCH 1/3] net/tap: support infrastructure to build the BPF filter Date: Tue, 31 Oct 2023 15:08:11 -0700 Message-ID: <20231031220921.96023-2-stephen@networkplumber.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20231031220921.96023-1-stephen@networkplumber.org> References: <20230716212544.5625-1-stephen@networkplumber.org> <20231031220921.96023-1-stephen@networkplumber.org> MIME-Version: 1.0 X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Move the BPF program related code into a subdirectory. And add a Makefile for building it. The code depends on include files from iproute2. But these are not public headers which iproute2 exports as a package API. Therefore make a local copy here. The standalone build was also broken because by commit ef5baf3486e0 ("replace packed attributes") which introduced __rte_packed into this code. Add a python program to extract the resulting BPF into a format that can be consumed by the TAP driver. Update the documentation. Signed-off-by: Stephen Hemminger --- doc/guides/nics/tap.rst | 11 +- drivers/net/tap/bpf/.gitignore | 1 + drivers/net/tap/bpf/Makefile | 18 ++ drivers/net/tap/bpf/bpf_api.h | 275 ++++++++++++++++++++ drivers/net/tap/bpf/bpf_elf.h | 53 ++++ drivers/net/tap/bpf/bpf_extract.py | 80 ++++++ drivers/net/tap/{ => bpf}/tap_bpf_program.c | 9 +- drivers/net/tap/tap_rss.h | 2 +- 8 files changed, 437 insertions(+), 12 deletions(-) create mode 100644 drivers/net/tap/bpf/.gitignore create mode 100644 drivers/net/tap/bpf/Makefile create mode 100644 drivers/net/tap/bpf/bpf_api.h create mode 100644 drivers/net/tap/bpf/bpf_elf.h create mode 100644 drivers/net/tap/bpf/bpf_extract.py rename drivers/net/tap/{ => bpf}/tap_bpf_program.c (97%) diff --git a/doc/guides/nics/tap.rst b/doc/guides/nics/tap.rst index 07df0d35a2..449e747994 100644 --- a/doc/guides/nics/tap.rst +++ b/doc/guides/nics/tap.rst @@ -256,15 +256,12 @@ C functions under different ELF sections. 2. Install ``LLVM`` library and ``clang`` compiler versions 3.7 and above -3. Compile ``tap_bpf_program.c`` via ``LLVM`` into an object file:: +3. Use make to compile `tap_bpf_program.c`` via ``LLVM`` into an object file + and extract the resulting instructions into ``tap_bpf_insn.h``. - clang -O2 -emit-llvm -c tap_bpf_program.c -o - | llc -march=bpf \ - -filetype=obj -o + cd bpf; make - -4. Use a tool that receives two parameters: an eBPF object file and a section -name, and prints out the section as a C array of eBPF instructions. -Embed the C array in your TAP PMD tree. +4. Recompile the TAP PMD. The C arrays are uploaded to the kernel using BPF system calls. diff --git a/drivers/net/tap/bpf/.gitignore b/drivers/net/tap/bpf/.gitignore new file mode 100644 index 0000000000..30a258f1af --- /dev/null +++ b/drivers/net/tap/bpf/.gitignore @@ -0,0 +1 @@ +tap_bpf_program.o diff --git a/drivers/net/tap/bpf/Makefile b/drivers/net/tap/bpf/Makefile new file mode 100644 index 0000000000..e5ae4e1f5a --- /dev/null +++ b/drivers/net/tap/bpf/Makefile @@ -0,0 +1,18 @@ +# SPDX-License-Identifier: BSD-3-Clause +# This file is not built as part of normal DPDK build. +# It is used to generate the eBPF code for TAP RSS. +CLANG=clang +CLANG_OPTS=-O2 +TARGET=../tap_bpf_insns.h + +all: $(TARGET) + +clean: + rm tap_bpf_program.o $(TARGET) + +tap_bpf_program.o: tap_bpf_program.c + $(CLANG) $(CLANG_OPTS) -emit-llvm -c $< -o - | \ + llc -march=bpf -filetype=obj -o $@ + +$(TARGET): bpf_extract.py tap_bpf_program.o + python3 bpf_extract.py tap_bpf_program.o $@ diff --git a/drivers/net/tap/bpf/bpf_api.h b/drivers/net/tap/bpf/bpf_api.h new file mode 100644 index 0000000000..5887d3a851 --- /dev/null +++ b/drivers/net/tap/bpf/bpf_api.h @@ -0,0 +1,275 @@ +/* SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause */ +#ifndef __BPF_API__ +#define __BPF_API__ + +/* Note: + * + * This file can be included into eBPF kernel programs. It contains + * a couple of useful helper functions, map/section ABI (bpf_elf.h), + * misc macros and some eBPF specific LLVM built-ins. + */ + +#include + +#include +#include +#include + +#include + +#include "bpf_elf.h" + +/** libbpf pin type. */ +enum libbpf_pin_type { + LIBBPF_PIN_NONE, + /* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */ + LIBBPF_PIN_BY_NAME, +}; + +/** Type helper macros. */ + +#define __uint(name, val) int (*name)[val] +#define __type(name, val) typeof(val) *name +#define __array(name, val) typeof(val) *name[] + +/** Misc macros. */ + +#ifndef __stringify +# define __stringify(X) #X +#endif + +#ifndef __maybe_unused +# define __maybe_unused __attribute__((__unused__)) +#endif + +#ifndef offsetof +# define offsetof(TYPE, MEMBER) __builtin_offsetof(TYPE, MEMBER) +#endif + +#ifndef likely +# define likely(X) __builtin_expect(!!(X), 1) +#endif + +#ifndef unlikely +# define unlikely(X) __builtin_expect(!!(X), 0) +#endif + +#ifndef htons +# define htons(X) __constant_htons((X)) +#endif + +#ifndef ntohs +# define ntohs(X) __constant_ntohs((X)) +#endif + +#ifndef htonl +# define htonl(X) __constant_htonl((X)) +#endif + +#ifndef ntohl +# define ntohl(X) __constant_ntohl((X)) +#endif + +#ifndef __inline__ +# define __inline__ __attribute__((always_inline)) +#endif + +/** Section helper macros. */ + +#ifndef __section +# define __section(NAME) \ + __attribute__((section(NAME), used)) +#endif + +#ifndef __section_tail +# define __section_tail(ID, KEY) \ + __section(__stringify(ID) "/" __stringify(KEY)) +#endif + +#ifndef __section_xdp_entry +# define __section_xdp_entry \ + __section(ELF_SECTION_PROG) +#endif + +#ifndef __section_cls_entry +# define __section_cls_entry \ + __section(ELF_SECTION_CLASSIFIER) +#endif + +#ifndef __section_act_entry +# define __section_act_entry \ + __section(ELF_SECTION_ACTION) +#endif + +#ifndef __section_lwt_entry +# define __section_lwt_entry \ + __section(ELF_SECTION_PROG) +#endif + +#ifndef __section_license +# define __section_license \ + __section(ELF_SECTION_LICENSE) +#endif + +#ifndef __section_maps +# define __section_maps \ + __section(ELF_SECTION_MAPS) +#endif + +/** Declaration helper macros. */ + +#ifndef BPF_LICENSE +# define BPF_LICENSE(NAME) \ + char ____license[] __section_license = NAME +#endif + +/** Classifier helper */ + +#ifndef BPF_H_DEFAULT +# define BPF_H_DEFAULT -1 +#endif + +/** BPF helper functions for tc. Individual flags are in linux/bpf.h */ + +#ifndef __BPF_FUNC +# define __BPF_FUNC(NAME, ...) \ + (* NAME)(__VA_ARGS__) __maybe_unused +#endif + +#ifndef BPF_FUNC +# define BPF_FUNC(NAME, ...) \ + __BPF_FUNC(NAME, __VA_ARGS__) = (void *) BPF_FUNC_##NAME +#endif + +/* Map access/manipulation */ +static void *BPF_FUNC(map_lookup_elem, void *map, const void *key); +static int BPF_FUNC(map_update_elem, void *map, const void *key, + const void *value, uint32_t flags); +static int BPF_FUNC(map_delete_elem, void *map, const void *key); + +/* Time access */ +static uint64_t BPF_FUNC(ktime_get_ns); + +/* Debugging */ + +/* FIXME: __attribute__ ((format(printf, 1, 3))) not possible unless + * llvm bug https://llvm.org/bugs/show_bug.cgi?id=26243 gets resolved. + * It would require ____fmt to be made const, which generates a reloc + * entry (non-map). + */ +static void BPF_FUNC(trace_printk, const char *fmt, int fmt_size, ...); + +#ifndef printt +# define printt(fmt, ...) \ + ({ \ + char ____fmt[] = fmt; \ + trace_printk(____fmt, sizeof(____fmt), ##__VA_ARGS__); \ + }) +#endif + +/* Random numbers */ +static uint32_t BPF_FUNC(get_prandom_u32); + +/* Tail calls */ +static void BPF_FUNC(tail_call, struct __sk_buff *skb, void *map, + uint32_t index); + +/* System helpers */ +static uint32_t BPF_FUNC(get_smp_processor_id); +static uint32_t BPF_FUNC(get_numa_node_id); + +/* Packet misc meta data */ +static uint32_t BPF_FUNC(get_cgroup_classid, struct __sk_buff *skb); +static int BPF_FUNC(skb_under_cgroup, void *map, uint32_t index); + +static uint32_t BPF_FUNC(get_route_realm, struct __sk_buff *skb); +static uint32_t BPF_FUNC(get_hash_recalc, struct __sk_buff *skb); +static uint32_t BPF_FUNC(set_hash_invalid, struct __sk_buff *skb); + +/* Packet redirection */ +static int BPF_FUNC(redirect, int ifindex, uint32_t flags); +static int BPF_FUNC(clone_redirect, struct __sk_buff *skb, int ifindex, + uint32_t flags); + +/* Packet manipulation */ +static int BPF_FUNC(skb_load_bytes, struct __sk_buff *skb, uint32_t off, + void *to, uint32_t len); +static int BPF_FUNC(skb_store_bytes, struct __sk_buff *skb, uint32_t off, + const void *from, uint32_t len, uint32_t flags); + +static int BPF_FUNC(l3_csum_replace, struct __sk_buff *skb, uint32_t off, + uint32_t from, uint32_t to, uint32_t flags); +static int BPF_FUNC(l4_csum_replace, struct __sk_buff *skb, uint32_t off, + uint32_t from, uint32_t to, uint32_t flags); +static int BPF_FUNC(csum_diff, const void *from, uint32_t from_size, + const void *to, uint32_t to_size, uint32_t seed); +static int BPF_FUNC(csum_update, struct __sk_buff *skb, uint32_t wsum); + +static int BPF_FUNC(skb_change_type, struct __sk_buff *skb, uint32_t type); +static int BPF_FUNC(skb_change_proto, struct __sk_buff *skb, uint32_t proto, + uint32_t flags); +static int BPF_FUNC(skb_change_tail, struct __sk_buff *skb, uint32_t nlen, + uint32_t flags); + +static int BPF_FUNC(skb_pull_data, struct __sk_buff *skb, uint32_t len); + +/* Event notification */ +static int __BPF_FUNC(skb_event_output, struct __sk_buff *skb, void *map, + uint64_t index, const void *data, uint32_t size) = + (void *) BPF_FUNC_perf_event_output; + +/* Packet vlan encap/decap */ +static int BPF_FUNC(skb_vlan_push, struct __sk_buff *skb, uint16_t proto, + uint16_t vlan_tci); +static int BPF_FUNC(skb_vlan_pop, struct __sk_buff *skb); + +/* Packet tunnel encap/decap */ +static int BPF_FUNC(skb_get_tunnel_key, struct __sk_buff *skb, + struct bpf_tunnel_key *to, uint32_t size, uint32_t flags); +static int BPF_FUNC(skb_set_tunnel_key, struct __sk_buff *skb, + const struct bpf_tunnel_key *from, uint32_t size, + uint32_t flags); + +static int BPF_FUNC(skb_get_tunnel_opt, struct __sk_buff *skb, + void *to, uint32_t size); +static int BPF_FUNC(skb_set_tunnel_opt, struct __sk_buff *skb, + const void *from, uint32_t size); + +/** LLVM built-ins, mem*() routines work for constant size */ + +#ifndef lock_xadd +# define lock_xadd(ptr, val) ((void) __sync_fetch_and_add(ptr, val)) +#endif + +#ifndef memset +# define memset(s, c, n) __builtin_memset((s), (c), (n)) +#endif + +#ifndef memcpy +# define memcpy(d, s, n) __builtin_memcpy((d), (s), (n)) +#endif + +#ifndef memmove +# define memmove(d, s, n) __builtin_memmove((d), (s), (n)) +#endif + +/* FIXME: __builtin_memcmp() is not yet fully useable unless llvm bug + * https://llvm.org/bugs/show_bug.cgi?id=26218 gets resolved. Also + * this one would generate a reloc entry (non-map), otherwise. + */ +#if 0 +#ifndef memcmp +# define memcmp(a, b, n) __builtin_memcmp((a), (b), (n)) +#endif +#endif + +unsigned long long load_byte(void *skb, unsigned long long off) + asm ("llvm.bpf.load.byte"); + +unsigned long long load_half(void *skb, unsigned long long off) + asm ("llvm.bpf.load.half"); + +unsigned long long load_word(void *skb, unsigned long long off) + asm ("llvm.bpf.load.word"); + +#endif /* __BPF_API__ */ diff --git a/drivers/net/tap/bpf/bpf_elf.h b/drivers/net/tap/bpf/bpf_elf.h new file mode 100644 index 0000000000..ea8a11c95c --- /dev/null +++ b/drivers/net/tap/bpf/bpf_elf.h @@ -0,0 +1,53 @@ +/* SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause */ +#ifndef __BPF_ELF__ +#define __BPF_ELF__ + +#include + +/* Note: + * + * Below ELF section names and bpf_elf_map structure definition + * are not (!) kernel ABI. It's rather a "contract" between the + * application and the BPF loader in tc. For compatibility, the + * section names should stay as-is. Introduction of aliases, if + * needed, are a possibility, though. + */ + +/* ELF section names, etc */ +#define ELF_SECTION_LICENSE "license" +#define ELF_SECTION_MAPS "maps" +#define ELF_SECTION_PROG "prog" +#define ELF_SECTION_CLASSIFIER "classifier" +#define ELF_SECTION_ACTION "action" + +#define ELF_MAX_MAPS 64 +#define ELF_MAX_LICENSE_LEN 128 + +/* Object pinning settings */ +#define PIN_NONE 0 +#define PIN_OBJECT_NS 1 +#define PIN_GLOBAL_NS 2 + +/* ELF map definition */ +struct bpf_elf_map { + __u32 type; + __u32 size_key; + __u32 size_value; + __u32 max_elem; + __u32 flags; + __u32 id; + __u32 pinning; + __u32 inner_id; + __u32 inner_idx; +}; + +#define BPF_ANNOTATE_KV_PAIR(name, type_key, type_val) \ + struct ____btf_map_##name { \ + type_key key; \ + type_val value; \ + }; \ + struct ____btf_map_##name \ + __attribute__ ((section(".maps." #name), used)) \ + ____btf_map_##name = { } + +#endif /* __BPF_ELF__ */ diff --git a/drivers/net/tap/bpf/bpf_extract.py b/drivers/net/tap/bpf/bpf_extract.py new file mode 100644 index 0000000000..d79fc61020 --- /dev/null +++ b/drivers/net/tap/bpf/bpf_extract.py @@ -0,0 +1,80 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: BSD-3-Clause +# Copyright (c) 2023 Stephen Hemminger + +import argparse +import sys +import struct +from tempfile import TemporaryFile +from elftools.elf.elffile import ELFFile + + +def load_sections(elffile): + result = [] + DATA = [("cls_q", "cls_q_insns"), ("l3_l4", "l3_l4_hash_insns")] + for name, tag in DATA: + section = elffile.get_section_by_name(name) + if section: + insns = struct.iter_unpack('> 4 + dst = bpf[1] & 0xf + off = bpf[2] + imm = bpf[3] + print('\t{{{:#02x}, {:4d}, {:4d}, {:8d}, {:#010x}}},'.format( + code, dst, src, off, imm), + file=out) + print('};', file=out) + + +def parse_args(): + parser = argparse.ArgumentParser() + parser.add_argument("input", + nargs='+', + help="input object file path or '-' for stdin") + parser.add_argument("output", help="output C file path or '-' for stdout") + return parser.parse_args() + + +def open_input(path): + if path == "-": + temp = TemporaryFile() + temp.write(sys.stdin.buffer.read()) + return temp + return open(path, "rb") + + +def open_output(path): + if path == "-": + return sys.stdout + return open(path, "w") + + +def write_header(output): + print("/* SPDX-License-Identifier: BSD-3-Clause", file=output) + print(" * Compiled BPF instructions do not edit", file=output) + print(" */\n", file=output) + print("#include ", file=output) + + +def main(): + args = parse_args() + + output = open_output(args.output) + write_header(output) + for path in args.input: + elffile = ELFFile(open_input(path)) + sections = load_sections(elffile) + dump_sections(sections, output) + + +if __name__ == "__main__": + main() diff --git a/drivers/net/tap/tap_bpf_program.c b/drivers/net/tap/bpf/tap_bpf_program.c similarity index 97% rename from drivers/net/tap/tap_bpf_program.c rename to drivers/net/tap/bpf/tap_bpf_program.c index 20c310e5e7..ff6f1606fb 100644 --- a/drivers/net/tap/tap_bpf_program.c +++ b/drivers/net/tap/bpf/tap_bpf_program.c @@ -14,9 +14,10 @@ #include #include #include -#include -#include "tap_rss.h" +#include "bpf_api.h" +#include "bpf_elf.h" +#include "../tap_rss.h" /** Create IPv4 address */ #define IPv4(a, b, c, d) ((__u32)(((a) & 0xff) << 24) | \ @@ -75,14 +76,14 @@ struct ipv4_l3_l4_tuple { __u32 dst_addr; __u16 dport; __u16 sport; -} __rte_packed; +} __attribute__((packed)); struct ipv6_l3_l4_tuple { __u8 src_addr[16]; __u8 dst_addr[16]; __u16 dport; __u16 sport; -} __rte_packed; +} __attribute__((packed)); static const __u8 def_rss_key[TAP_RSS_HASH_KEY_SIZE] = { 0xd1, 0x81, 0xc6, 0x2c, diff --git a/drivers/net/tap/tap_rss.h b/drivers/net/tap/tap_rss.h index 48c151cf6b..dff46a012f 100644 --- a/drivers/net/tap/tap_rss.h +++ b/drivers/net/tap/tap_rss.h @@ -35,6 +35,6 @@ struct rss_key { __u32 key_size; __u32 queues[TAP_MAX_QUEUES]; __u32 nb_queues; -} __rte_packed; +} __attribute__((packed)); #endif /* _TAP_RSS_H_ */