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=-15.7 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 0586CC433B4 for ; Fri, 2 Apr 2021 12:20:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B818E61159 for ; Fri, 2 Apr 2021 12:20:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235366AbhDBMU1 (ORCPT ); Fri, 2 Apr 2021 08:20:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46388 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235357AbhDBMU0 (ORCPT ); Fri, 2 Apr 2021 08:20:26 -0400 Received: from mail-pg1-x52b.google.com (mail-pg1-x52b.google.com [IPv6:2607:f8b0:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CA3BDC0613E6; Fri, 2 Apr 2021 05:20:25 -0700 (PDT) Received: by mail-pg1-x52b.google.com with SMTP id y3so712515pgi.0; Fri, 02 Apr 2021 05:20:25 -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=VhU4PMXFi3IhgQqMUuD2AArV4T8a5Mz8kKfY2Qc6o6Y=; b=cYaeYQEn+V1ven4GvCskA+xgYwcNvFUCcXGOBEnfgghgMStFE7M7HIkQergvkGEUVg 5mYpFpXZ26klBbd+77GQgdvt3fCt+axBuc2Wx9brK83aLMD4TN7LTQ/seENAOs6g0oKf hzZT6JJXr+6UUjVHazfIMzMJ5WvBDGooHBIa+tF8HsMdJqSEvqkiClYmTImd6xX8ArI4 yxRZJORV9xo0LLcLmB+FuIHqEK/pu0csK9QuqsT0k6XrQxoDSyC7Hg6xtlKdlegEttny pS6Dj8bYCOBjrtAqB6o/A4JCtpbcQoxTR2ZDoqXB0RaAwGxUhsa1OrTB4zb58bsJV8fF jAcQ== 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=VhU4PMXFi3IhgQqMUuD2AArV4T8a5Mz8kKfY2Qc6o6Y=; b=pgquenwuPgzSZi4nmsVDEDukt2LerQv59sr9hgwdQPJV+uiz4IkLUGRIj7aPxvz/ME 3t6CML8KQSlUu9HhgCing1vmnklA9gat9WexVh6++pgyT2zaWGCVs9kMLd9BbmniBH+D GI7E75Q0smaRKzxMBdjK8PgfZ1H1xXr6BnuQNUPCalh9HpNA4n74S8TZROvnVJLAWN0C v9m2h+o4kQTEQD8uL9yTYKt0czyTymxyOulGCsLBYubKtw2ujw+XTIZD3jWtQV7F4eCg JTC7sSfe57lpN1mGeISAMTT8YRPQqfLe5I63QiT6EJuJqEpZnZbUKaYjjijtZlIN+K+1 5ueg== X-Gm-Message-State: AOAM531YwLSQ4yuJe5+8qE8F7tDTjsY9NsS4nYLfy0N6NShr9L3+Be3U 5/h2qcrEc7cIm5KuQSHlrZE1MJdN7B5QxQ== X-Google-Smtp-Source: ABdhPJzKHPgQPioVV/L6D75R5Ja4eTAxxhby+g4RrnoRyIm9O0qV9+IXoyU+t8cXDryqKhVOmQwpng== X-Received: by 2002:a62:6497:0:b029:220:d96a:8a79 with SMTP id y145-20020a6264970000b0290220d96a8a79mr11904801pfb.23.1617366024783; Fri, 02 Apr 2021 05:20:24 -0700 (PDT) Received: from Leo-laptop-t470s.redhat.com ([209.132.188.80]) by smtp.gmail.com with ESMTPSA id g15sm8760913pfk.36.2021.04.02.05.20.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 02 Apr 2021 05:20:24 -0700 (PDT) From: Hangbin Liu To: bpf@vger.kernel.org Cc: netdev@vger.kernel.org, =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= , Jiri Benc , Jesper Dangaard Brouer , Eelco Chaudron , ast@kernel.org, Daniel Borkmann , Lorenzo Bianconi , David Ahern , Andrii Nakryiko , Alexei Starovoitov , John Fastabend , Maciej Fijalkowski , =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= , Hangbin Liu Subject: [PATCHv4 bpf-next 2/4] xdp: extend xdp_redirect_map with broadcast support Date: Fri, 2 Apr 2021 20:19:52 +0800 Message-Id: <20210402121954.3568992-3-liuhangbin@gmail.com> X-Mailer: git-send-email 2.26.3 In-Reply-To: <20210402121954.3568992-1-liuhangbin@gmail.com> References: <20210402121954.3568992-1-liuhangbin@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org This patch add two flags BPF_F_BROADCAST and BPF_F_EXCLUDE_INGRESS to extend xdp_redirect_map for broadcast support. Keep the general data path in net/core/filter.c and the native data path in kernel/bpf/devmap.c so we can use direct calls to get better performace. Here is the performance result by using xdp_redirect_{map, map_multi} in sample/bpf and send pkts via pktgen cmd: ./pktgen_sample03_burst_single_flow.sh -i eno1 -d $dst_ip -m $dst_mac -t 10 -s 64 There are some drop back as we need to loop the map and get each interface. Version | Test | Generic | Native 5.12 rc2 | redirect_map i40e->i40e | 2.0M | 9.8M 5.12 rc2 | redirect_map i40e->veth | 1.8M | 12.0M 5.12 rc2 + patch | redirect_map i40e->i40e | 2.0M | 9.6M 5.12 rc2 + patch | redirect_map i40e->veth | 1.7M | 12.0M 5.12 rc2 + patch | redirect_map multi i40e->i40e | 1.6M | 7.8M 5.12 rc2 + patch | redirect_map multi i40e->veth | 1.4M | 9.3M 5.12 rc2 + patch | redirect_map multi i40e->mlx4+veth | 1.0M | 3.4M Signed-off-by: Hangbin Liu --- v4: a) add a new argument flag_mask to __bpf_xdp_redirect_map() filter out invalid map. b) __bpf_xdp_redirect_map() sets the map pointer if the broadcast flag is set and clears it if the flag isn't set c) xdp_do_redirect() does the READ_ONCE/WRITE_ONCE on ri->map to check if we should enqueue multi v3: a) Rebase the code on Björn's "bpf, xdp: Restructure redirect actions". - Add struct bpf_map *map back to struct bpf_redirect_info as we need it for multicast. - Add bpf_clear_redirect_map() back for devmap.c - Add devmap_lookup_elem() as we need it in general path. b) remove tmp_key in devmap_get_next_obj() v2: Fix flag renaming issue in v1 --- include/linux/bpf.h | 22 ++++++ include/linux/filter.h | 18 ++++- include/net/xdp.h | 1 + include/uapi/linux/bpf.h | 17 ++++- kernel/bpf/cpumap.c | 3 +- kernel/bpf/devmap.c | 133 ++++++++++++++++++++++++++++++++- net/core/filter.c | 97 +++++++++++++++++++++++- net/core/xdp.c | 29 +++++++ net/xdp/xskmap.c | 3 +- tools/include/uapi/linux/bpf.h | 17 ++++- 10 files changed, 326 insertions(+), 14 deletions(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 9fdd839b418c..d5745c6000bc 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1492,11 +1492,15 @@ struct sk_buff; struct bpf_dtab_netdev; struct bpf_cpu_map_entry; +struct bpf_dtab_netdev *devmap_lookup_elem(struct bpf_map *map, u32 key); void __dev_flush(void); int dev_xdp_enqueue(struct net_device *dev, struct xdp_buff *xdp, struct net_device *dev_rx); int dev_map_enqueue(struct bpf_dtab_netdev *dst, struct xdp_buff *xdp, struct net_device *dev_rx); +bool dst_dev_is_ingress(struct bpf_dtab_netdev *obj, int ifindex); +int dev_map_enqueue_multi(struct xdp_buff *xdp, struct net_device *dev_rx, + struct bpf_map *map, bool exclude_ingress); int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, struct sk_buff *skb, struct bpf_prog *xdp_prog); bool dev_map_can_have_prog(struct bpf_map *map); @@ -1639,6 +1643,11 @@ static inline int bpf_obj_get_user(const char __user *pathname, int flags) return -EOPNOTSUPP; } +static inline struct net_device *devmap_lookup_elem(struct bpf_map *map, u32 key) +{ + return NULL; +} + static inline bool dev_map_can_have_prog(struct bpf_map *map) { return false; @@ -1666,6 +1675,19 @@ int dev_map_enqueue(struct bpf_dtab_netdev *dst, struct xdp_buff *xdp, return 0; } +static inline +bool dst_dev_is_ingress(struct bpf_dtab_netdev *obj, int ifindex) +{ + return false; +} + +static inline +int dev_map_enqueue_multi(struct xdp_buff *xdp, struct net_device *dev_rx, + struct bpf_map *map, bool exclude_ingress) +{ + return 0; +} + struct sk_buff; static inline int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, diff --git a/include/linux/filter.h b/include/linux/filter.h index 9a09547bc7ba..e4885b42d754 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -646,6 +646,7 @@ struct bpf_redirect_info { u32 flags; u32 tgt_index; void *tgt_value; + struct bpf_map *map; u32 map_id; enum bpf_map_type map_type; u32 kern_flags; @@ -1464,17 +1465,18 @@ static inline bool bpf_sk_lookup_run_v6(struct net *net, int protocol, } #endif /* IS_ENABLED(CONFIG_IPV6) */ -static __always_inline int __bpf_xdp_redirect_map(struct bpf_map *map, u32 ifindex, u64 flags, +static __always_inline int __bpf_xdp_redirect_map(struct bpf_map *map, u32 ifindex, + u64 flags, u64 flag_mask, void *lookup_elem(struct bpf_map *map, u32 key)) { struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); /* Lower bits of the flags are used as return code on lookup failure */ - if (unlikely(flags > XDP_TX)) + if (unlikely(flags & ~(BPF_F_ACTION_MASK | flag_mask))) return XDP_ABORTED; ri->tgt_value = lookup_elem(map, ifindex); - if (unlikely(!ri->tgt_value)) { + if (unlikely(!ri->tgt_value) && !(flags & BPF_F_BROADCAST)) { /* If the lookup fails we want to clear out the state in the * redirect_info struct completely, so that if an eBPF program * performs multiple lookups, the last one always takes @@ -1482,13 +1484,21 @@ static __always_inline int __bpf_xdp_redirect_map(struct bpf_map *map, u32 ifind */ ri->map_id = INT_MAX; /* Valid map id idr range: [1,INT_MAX[ */ ri->map_type = BPF_MAP_TYPE_UNSPEC; - return flags; + return flags & BPF_F_ACTION_MASK; } ri->tgt_index = ifindex; ri->map_id = map->id; ri->map_type = map->map_type; + if (flags & BPF_F_BROADCAST) { + WRITE_ONCE(ri->map, map); + ri->flags = flags; + } else { + WRITE_ONCE(ri->map, NULL); + ri->flags = 0; + } + return XDP_REDIRECT; } diff --git a/include/net/xdp.h b/include/net/xdp.h index a5bc214a49d9..5533f0ab2afc 100644 --- a/include/net/xdp.h +++ b/include/net/xdp.h @@ -170,6 +170,7 @@ struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf, struct sk_buff *xdp_build_skb_from_frame(struct xdp_frame *xdpf, struct net_device *dev); int xdp_alloc_skb_bulk(void **skbs, int n_skb, gfp_t gfp); +struct xdp_frame *xdpf_clone(struct xdp_frame *xdpf); static inline void xdp_convert_frame_to_buff(struct xdp_frame *frame, struct xdp_buff *xdp) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 49371eba98ba..fe2c35bcc880 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -2513,8 +2513,12 @@ union bpf_attr { * The lower two bits of *flags* are used as the return code if * the map lookup fails. This is so that the return value can be * one of the XDP program return codes up to **XDP_TX**, as chosen - * by the caller. Any higher bits in the *flags* argument must be - * unset. + * by the caller. The higher bits of *flags* can be set to + * BPF_F_BROADCAST or BPF_F_EXCLUDE_INGRESS as defined below. + * + * With BPF_F_BROADCAST the packet will be broadcasted to all the + * interfaces in the map. with BPF_F_EXCLUDE_INGRESS the ingress + * interface will be excluded when do broadcasting. * * See also **bpf_redirect**\ (), which only supports redirecting * to an ifindex, but doesn't require a map to do so. @@ -5015,6 +5019,15 @@ enum { BPF_F_BPRM_SECUREEXEC = (1ULL << 0), }; +/* Flags for bpf_redirect_map helper */ +enum { + BPF_F_BROADCAST = (1ULL << 3), + BPF_F_EXCLUDE_INGRESS = (1ULL << 4), +}; + +#define BPF_F_ACTION_MASK (XDP_ABORTED | XDP_DROP | XDP_PASS | XDP_TX) +#define BPF_F_REDIR_MASK (BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS) + #define __bpf_md_ptr(type, name) \ union { \ type name; \ diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c index 0cf2791d5099..2c33a7a09783 100644 --- a/kernel/bpf/cpumap.c +++ b/kernel/bpf/cpumap.c @@ -601,7 +601,8 @@ static int cpu_map_get_next_key(struct bpf_map *map, void *key, void *next_key) static int cpu_map_redirect(struct bpf_map *map, u32 ifindex, u64 flags) { - return __bpf_xdp_redirect_map(map, ifindex, flags, __cpu_map_lookup_elem); + return __bpf_xdp_redirect_map(map, ifindex, flags, 0, + __cpu_map_lookup_elem); } static int cpu_map_btf_id; diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index 3980fb3bfb09..c8452c5f40f8 100644 --- a/kernel/bpf/devmap.c +++ b/kernel/bpf/devmap.c @@ -198,6 +198,7 @@ static void dev_map_free(struct bpf_map *map) list_del_rcu(&dtab->list); spin_unlock(&dev_map_lock); + bpf_clear_redirect_map(map); synchronize_rcu(); /* Make sure prior __dev_map_entry_free() have completed. */ @@ -451,6 +452,24 @@ static void *__dev_map_lookup_elem(struct bpf_map *map, u32 key) return obj; } +struct bpf_dtab_netdev *devmap_lookup_elem(struct bpf_map *map, u32 key) +{ + struct bpf_dtab_netdev *obj = NULL; + + switch (map->map_type) { + case BPF_MAP_TYPE_DEVMAP: + obj = __dev_map_lookup_elem(map, key); + break; + case BPF_MAP_TYPE_DEVMAP_HASH: + obj = __dev_map_hash_lookup_elem(map, key); + break; + default: + break; + } + + return obj; +} + /* Runs under RCU-read-side, plus in softirq under NAPI protection. * Thus, safe percpu variable access. */ @@ -515,6 +534,114 @@ int dev_map_enqueue(struct bpf_dtab_netdev *dst, struct xdp_buff *xdp, return __xdp_enqueue(dev, xdp, dev_rx, dst->xdp_prog); } +/* Use direct call in fast path instead of map->ops->map_get_next_key() */ +static int devmap_get_next_key(struct bpf_map *map, void *key, void *next_key) +{ + switch (map->map_type) { + case BPF_MAP_TYPE_DEVMAP: + return dev_map_get_next_key(map, key, next_key); + case BPF_MAP_TYPE_DEVMAP_HASH: + return dev_map_hash_get_next_key(map, key, next_key); + default: + break; + } + + return -ENOENT; +} + +bool dst_dev_is_ingress(struct bpf_dtab_netdev *dst, int ifindex) +{ + return dst->dev->ifindex == ifindex; +} + +static struct bpf_dtab_netdev *devmap_get_next_obj(struct xdp_buff *xdp, + struct bpf_map *map, + u32 *key, u32 *next_key, + int ex_ifindex) +{ + struct bpf_dtab_netdev *obj; + struct net_device *dev; + u32 index; + int err; + + err = devmap_get_next_key(map, key, next_key); + if (err) + return NULL; + + /* When using dev map hash, we could restart the hashtab traversal + * in case the key has been updated/removed in the mean time. + * So we may end up potentially looping due to traversal restarts + * from first elem. + * + * Let's use map's max_entries to limit the loop number. + */ + for (index = 0; index < map->max_entries; index++) { + obj = devmap_lookup_elem(map, *next_key); + if (!obj || dst_dev_is_ingress(obj, ex_ifindex)) + goto find_next; + + dev = obj->dev; + + if (!dev->netdev_ops->ndo_xdp_xmit) + goto find_next; + + err = xdp_ok_fwd_dev(dev, xdp->data_end - xdp->data); + if (unlikely(err)) + goto find_next; + + return obj; + +find_next: + key = next_key; + err = devmap_get_next_key(map, key, next_key); + if (err) + break; + } + + return NULL; +} + +int dev_map_enqueue_multi(struct xdp_buff *xdp, struct net_device *dev_rx, + struct bpf_map *map, bool exclude_ingress) +{ + struct bpf_dtab_netdev *obj = NULL, *next_obj = NULL; + struct xdp_frame *xdpf, *nxdpf; + u32 key, next_key; + int ex_ifindex; + + ex_ifindex = exclude_ingress ? dev_rx->ifindex : 0; + + /* Find first available obj */ + obj = devmap_get_next_obj(xdp, map, NULL, &key, ex_ifindex); + if (!obj) + return -ENOENT; + + xdpf = xdp_convert_buff_to_frame(xdp); + if (unlikely(!xdpf)) + return -EOVERFLOW; + + for (;;) { + /* Check if we still have one more available obj */ + next_obj = devmap_get_next_obj(xdp, map, &key, &next_key, ex_ifindex); + if (!next_obj) { + bq_enqueue(obj->dev, xdpf, dev_rx, obj->xdp_prog); + return 0; + } + + nxdpf = xdpf_clone(xdpf); + if (unlikely(!nxdpf)) { + xdp_return_frame_rx_napi(xdpf); + return -ENOMEM; + } + + bq_enqueue(obj->dev, nxdpf, dev_rx, obj->xdp_prog); + + /* Deal with next obj */ + obj = next_obj; + key = next_key; + } +} + int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, struct sk_buff *skb, struct bpf_prog *xdp_prog) { @@ -755,12 +882,14 @@ static int dev_map_hash_update_elem(struct bpf_map *map, void *key, void *value, static int dev_map_redirect(struct bpf_map *map, u32 ifindex, u64 flags) { - return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_lookup_elem); + return __bpf_xdp_redirect_map(map, ifindex, flags, BPF_F_REDIR_MASK, + __dev_map_lookup_elem); } static int dev_hash_map_redirect(struct bpf_map *map, u32 ifindex, u64 flags) { - return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_hash_lookup_elem); + return __bpf_xdp_redirect_map(map, ifindex, flags, BPF_F_REDIR_MASK, + __dev_map_hash_lookup_elem); } static int dev_map_btf_id; diff --git a/net/core/filter.c b/net/core/filter.c index cae56d08a670..08a4d3869056 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3926,6 +3926,23 @@ void xdp_do_flush(void) } EXPORT_SYMBOL_GPL(xdp_do_flush); +void bpf_clear_redirect_map(struct bpf_map *map) +{ + struct bpf_redirect_info *ri; + int cpu; + + for_each_possible_cpu(cpu) { + ri = per_cpu_ptr(&bpf_redirect_info, cpu); + /* Avoid polluting remote cacheline due to writes if + * not needed. Once we pass this test, we need the + * cmpxchg() to make sure it hasn't been changed in + * the meantime by remote CPU. + */ + if (unlikely(READ_ONCE(ri->map) == map)) + cmpxchg(&ri->map, map, NULL); + } +} + int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, struct bpf_prog *xdp_prog) { @@ -3933,16 +3950,28 @@ int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, enum bpf_map_type map_type = ri->map_type; void *fwd = ri->tgt_value; u32 map_id = ri->map_id; + bool exclude_ingress; + struct bpf_map *map; int err; ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */ ri->map_type = BPF_MAP_TYPE_UNSPEC; + map = READ_ONCE(ri->map); + if (map) { + WRITE_ONCE(ri->map, NULL); + exclude_ingress = ri->flags & BPF_F_EXCLUDE_INGRESS; + ri->flags = 0; + } + switch (map_type) { case BPF_MAP_TYPE_DEVMAP: fallthrough; case BPF_MAP_TYPE_DEVMAP_HASH: - err = dev_map_enqueue(fwd, xdp, dev); + if (map) + err = dev_map_enqueue_multi(xdp, dev, map, exclude_ingress); + else + err = dev_map_enqueue(fwd, xdp, dev); break; case BPF_MAP_TYPE_CPUMAP: err = cpu_map_enqueue(fwd, xdp, dev); @@ -3976,6 +4005,57 @@ int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, } EXPORT_SYMBOL_GPL(xdp_do_redirect); +static int dev_map_redirect_multi(struct net_device *dev, struct sk_buff *skb, + struct bpf_prog *xdp_prog, struct bpf_map *map, + bool exclude_ingress) +{ + struct bpf_dtab_netdev *dst; + u32 key, next_key, index; + struct sk_buff *nskb; + void *fwd; + int err; + + err = map->ops->map_get_next_key(map, NULL, &key); + if (err) + return err; + + /* When using dev map hash, we could restart the hashtab traversal + * in case the key has been updated/removed in the mean time. + * So we may end up potentially looping due to traversal restarts + * from first elem. + * + * Let's use map's max_entries to limit the loop number. + */ + + for (index = 0; index < map->max_entries; index++) { + fwd = devmap_lookup_elem(map, key); + if (fwd) { + dst = (struct bpf_dtab_netdev *)fwd; + if (dst_dev_is_ingress(dst, exclude_ingress ? dev->ifindex : 0)) + goto find_next; + + nskb = skb_clone(skb, GFP_ATOMIC); + if (!nskb) + return -ENOMEM; + + /* Try forword next one no mater the current forward + * succeed or not. + */ + dev_map_generic_redirect(dst, nskb, xdp_prog); + } + +find_next: + err = map->ops->map_get_next_key(map, &key, &next_key); + if (err) + break; + + key = next_key; + } + + consume_skb(skb); + return 0; +} + static int xdp_do_generic_redirect_map(struct net_device *dev, struct sk_buff *skb, struct xdp_buff *xdp, @@ -3984,13 +4064,26 @@ static int xdp_do_generic_redirect_map(struct net_device *dev, enum bpf_map_type map_type, u32 map_id) { struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); + bool exclude_ingress; + struct bpf_map *map; int err; + map = READ_ONCE(ri->map); + if (map) { + WRITE_ONCE(ri->map, NULL); + exclude_ingress = ri->flags & BPF_F_EXCLUDE_INGRESS; + ri->flags = 0; + } + switch (map_type) { case BPF_MAP_TYPE_DEVMAP: fallthrough; case BPF_MAP_TYPE_DEVMAP_HASH: - err = dev_map_generic_redirect(fwd, skb, xdp_prog); + if (map) + err = dev_map_redirect_multi(dev, skb, xdp_prog, map, + exclude_ingress); + else + err = dev_map_generic_redirect(fwd, skb, xdp_prog); if (unlikely(err)) goto err; break; diff --git a/net/core/xdp.c b/net/core/xdp.c index 05354976c1fc..aba84d04642b 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -583,3 +583,32 @@ struct sk_buff *xdp_build_skb_from_frame(struct xdp_frame *xdpf, return __xdp_build_skb_from_frame(xdpf, skb, dev); } EXPORT_SYMBOL_GPL(xdp_build_skb_from_frame); + +struct xdp_frame *xdpf_clone(struct xdp_frame *xdpf) +{ + unsigned int headroom, totalsize; + struct xdp_frame *nxdpf; + struct page *page; + void *addr; + + headroom = xdpf->headroom + sizeof(*xdpf); + totalsize = headroom + xdpf->len; + + if (unlikely(totalsize > PAGE_SIZE)) + return NULL; + page = dev_alloc_page(); + if (!page) + return NULL; + addr = page_to_virt(page); + + memcpy(addr, xdpf, totalsize); + + nxdpf = addr; + nxdpf->data = addr + headroom; + nxdpf->frame_sz = PAGE_SIZE; + nxdpf->mem.type = MEM_TYPE_PAGE_ORDER0; + nxdpf->mem.id = 0; + + return nxdpf; +} +EXPORT_SYMBOL_GPL(xdpf_clone); diff --git a/net/xdp/xskmap.c b/net/xdp/xskmap.c index 67b4ce504852..9df75ea4a567 100644 --- a/net/xdp/xskmap.c +++ b/net/xdp/xskmap.c @@ -226,7 +226,8 @@ static int xsk_map_delete_elem(struct bpf_map *map, void *key) static int xsk_map_redirect(struct bpf_map *map, u32 ifindex, u64 flags) { - return __bpf_xdp_redirect_map(map, ifindex, flags, __xsk_map_lookup_elem); + return __bpf_xdp_redirect_map(map, ifindex, flags, 0, + __xsk_map_lookup_elem); } void xsk_map_try_sock_delete(struct xsk_map *map, struct xdp_sock *xs, diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 69902603012c..46e42a783f4e 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -2513,8 +2513,12 @@ union bpf_attr { * The lower two bits of *flags* are used as the return code if * the map lookup fails. This is so that the return value can be * one of the XDP program return codes up to **XDP_TX**, as chosen - * by the caller. Any higher bits in the *flags* argument must be - * unset. + * by the caller. The higher bits of *flags* can be set to + * BPF_F_BROADCAST or BPF_F_EXCLUDE_INGRESS as defined below. + * + * With BPF_F_BROADCAST the packet will be broadcasted to all the + * interfaces in the map. with BPF_F_EXCLUDE_INGRESS the ingress + * interface will be excluded when do broadcasting. * * See also **bpf_redirect**\ (), which only supports redirecting * to an ifindex, but doesn't require a map to do so. @@ -5009,6 +5013,15 @@ enum { BPF_F_BPRM_SECUREEXEC = (1ULL << 0), }; +/* Flags for bpf_redirect_map helper */ +enum { + BPF_F_BROADCAST = (1ULL << 3), + BPF_F_EXCLUDE_INGRESS = (1ULL << 4), +}; + +#define BPF_F_ACTION_MASK (XDP_ABORTED | XDP_DROP | XDP_PASS | XDP_TX) +#define BPF_F_REDIR_MASK (BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS) + #define __bpf_md_ptr(type, name) \ union { \ type name; \ -- 2.26.3