From patchwork Thu Aug 24 14:30:18 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jamal Hadi Salim X-Patchwork-Id: 13364261 X-Patchwork-Delegate: kuba@kernel.org Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1E1B7134A3 for ; Thu, 24 Aug 2023 14:30:32 +0000 (UTC) Received: from mail-yb1-xb30.google.com (mail-yb1-xb30.google.com [IPv6:2607:f8b0:4864:20::b30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EF487193 for ; Thu, 24 Aug 2023 07:30:30 -0700 (PDT) Received: by mail-yb1-xb30.google.com with SMTP id 3f1490d57ef6-d62bdd1a97dso6616721276.3 for ; Thu, 24 Aug 2023 07:30:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mojatatu-com.20221208.gappssmtp.com; s=20221208; t=1692887430; x=1693492230; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=Xdjidep6myuIwwtrqZvROOxc+Y+z4o49otQGiEUvB48=; b=FRQmygyIx9Kqqr/OvO5k6vvLQVDIANyVaBZosJ+TIAqhEw7kLQwo3/S/hKeNQtUQbM XKcGyULlEaGrTAreNPsysIADIOKhORRF+qdu6raXWRwbogSEo5wUPtO47ra6Z3pllo7t kStG0tDR65HM/1ztJ4iSqaKsYuUpX8bcp67u0cQKXmBMqVTf3Ay377Q09UT9ytW9cfZ6 GbY6jJzxWSimV3lzazfJH4oQxd2FfQ1CTJjBtskbjF/ITsFFJ43pGp5GhOdwS5XYfThF MQIrTosVJbbR7k7udbru3JSZQWTLg0WFm/YzNgeObXukLzZN87+Z86sq6gwQiYm6UXRQ Eyww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692887430; x=1693492230; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Xdjidep6myuIwwtrqZvROOxc+Y+z4o49otQGiEUvB48=; b=Dhu3lMSYDIKLvwnTs+OF500FpDW0ebA41GaHukn4+vvLuKaSKnALfBHu5eJN8hquyD HyFib+1IG6hyaf3pDV+wdgU6FdKC9XI3EYQ9HETaF9ydONhfUt7cbSShrVaOCkJYtzbt WbNTmGymHQzd+LcEK/cbTHZh9dvpFiaEjs55GDv5uiZmw4uJEAkSZ0S41Q/wxylTysCj 7lsaEuMdXJgdF/tsaeJYIW2ma4xYOAKycuGC900PRXE+F0dfosxKmLZdYzvsIHXKqiBL iyTLbfra1KNYPYBqkTN4ro6vBJbX/nPm/dg3Qw/AdBziTa7RNeCRbEvC1rwXRGPev5dZ PeFg== X-Gm-Message-State: AOJu0YzuKe63D/17ofWJrPJ1GelAS8Xo1UQ6wcOhNKRVql7Vsk+ydrgL 7hX4i4JIT2CsnxmLPlEnmMdkYmCGajcnH0FPWAj4QBzDZtkjH09HHyY= X-Google-Smtp-Source: AGHT+IHPYAGrs0oTrlzFowTu7pjnjbTRQZ1/83HjpMOMLODxHrhbSynpDoIX73PhxYuiiYKwd3dz4tzBxB6tZ+i/SaY= X-Received: by 2002:a0d:d5c3:0:b0:580:308b:48e6 with SMTP id x186-20020a0dd5c3000000b00580308b48e6mr15625345ywd.20.1692887430150; Thu, 24 Aug 2023 07:30:30 -0700 (PDT) Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20230819163515.2266246-1-victor@mojatatu.com> <20230819163515.2266246-4-victor@mojatatu.com> In-Reply-To: <20230819163515.2266246-4-victor@mojatatu.com> From: Jamal Hadi Salim Date: Thu, 24 Aug 2023 10:30:18 -0400 Message-ID: Subject: Weird sparse error WAS( [PATCH net-next v2 3/3] net/sched: act_blockcast: Introduce blockcast tc action To: Dan Carpenter Cc: Simon Horman , Linux Kernel Network Developers X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: kuba@kernel.org Dan/Simon, Can someone help explain this error on the code below: ../net/sched/act_blockcast.c:213:9: warning: context imbalance in 'tcf_blockcast_init' - different lock contexts for basic block Looks like a false positive ... cheers, jamal ---------- Forwarded message --------- From: Victor Nogueira Date: Sat, Aug 19, 2023 at 12:35 PM Subject: [PATCH net-next v2 3/3] net/sched: act_blockcast: Introduce blockcast tc action To: , , , , , , , Cc: , , , , This action takes advantage of the presence of tc block ports set in the datapath and broadcast a packet to all ports on that set with exception of the port in which it arrived on.. Example usage: $ tc qdisc add dev ens7 ingress block 22 $ tc qdisc add dev ens8 ingress block 22 Now we can add a filter using the block index: $ tc filter add block 22 protocol ip pref 25 \ flower dst_ip 192.168.0.0/16 action blockcast Co-developed-by: Jamal Hadi Salim Signed-off-by: Jamal Hadi Salim Co-developed-by: Pedro Tammela Signed-off-by: Pedro Tammela Signed-off-by: Victor Nogueira --- include/net/tc_wrapper.h | 5 + net/sched/Kconfig | 13 ++ net/sched/Makefile | 1 + net/sched/act_blockcast.c | 299 ++++++++++++++++++++++++++++++++++++++ 4 files changed, 318 insertions(+) create mode 100644 net/sched/act_blockcast.c +module_init(blockcast_init_module); +module_exit(blockcast_cleanup_module); -- 2.25.1 diff --git a/include/net/tc_wrapper.h b/include/net/tc_wrapper.h index a6d481b5bcbc..8ef848968be7 100644 --- a/include/net/tc_wrapper.h +++ b/include/net/tc_wrapper.h @@ -28,6 +28,7 @@ TC_INDIRECT_ACTION_DECLARE(tcf_csum_act); TC_INDIRECT_ACTION_DECLARE(tcf_ct_act); TC_INDIRECT_ACTION_DECLARE(tcf_ctinfo_act); TC_INDIRECT_ACTION_DECLARE(tcf_gact_act); +TC_INDIRECT_ACTION_DECLARE(tcf_blockcast_run); TC_INDIRECT_ACTION_DECLARE(tcf_gate_act); TC_INDIRECT_ACTION_DECLARE(tcf_ife_act); TC_INDIRECT_ACTION_DECLARE(tcf_ipt_act); @@ -57,6 +58,10 @@ static inline int tc_act(struct sk_buff *skb, const struct tc_action *a, if (a->ops->act == tcf_mirred_act) return tcf_mirred_act(skb, a, res); #endif +#if IS_BUILTIN(CONFIG_NET_ACT_BLOCKCAST) + if (a->ops->act == tcf_blockcast_run) + return tcf_blockcast_run(skb, a, res); +#endif #if IS_BUILTIN(CONFIG_NET_ACT_PEDIT) if (a->ops->act == tcf_pedit_act) return tcf_pedit_act(skb, a, res); diff --git a/net/sched/Kconfig b/net/sched/Kconfig index 4b95cb1ac435..1b0edf1287d0 100644 --- a/net/sched/Kconfig +++ b/net/sched/Kconfig @@ -780,6 +780,19 @@ config NET_ACT_SIMP To compile this code as a module, choose M here: the module will be called act_simple. +config NET_ACT_BLOCKCAST + tristate "TC block Multicast" + depends on NET_CLS_ACT + help + Say Y here to add an action that will multicast an skb to egress of + all netdevs that belong to a tc block except for the netdev on which + the skb arrived on + + If unsure, say N. + + To compile this code as a module, choose M here: the + module will be called act_blockcast. + config NET_ACT_SKBEDIT tristate "SKB Editing" depends on NET_CLS_ACT diff --git a/net/sched/Makefile b/net/sched/Makefile index b5fd49641d91..2cdcf30645eb 100644 --- a/net/sched/Makefile +++ b/net/sched/Makefile @@ -17,6 +17,7 @@ obj-$(CONFIG_NET_ACT_IPT) += act_ipt.o obj-$(CONFIG_NET_ACT_NAT) += act_nat.o obj-$(CONFIG_NET_ACT_PEDIT) += act_pedit.o obj-$(CONFIG_NET_ACT_SIMP) += act_simple.o +obj-$(CONFIG_NET_ACT_BLOCKCAST) += act_blockcast.o obj-$(CONFIG_NET_ACT_SKBEDIT) += act_skbedit.o obj-$(CONFIG_NET_ACT_CSUM) += act_csum.o obj-$(CONFIG_NET_ACT_MPLS) += act_mpls.o diff --git a/net/sched/act_blockcast.c b/net/sched/act_blockcast.c new file mode 100644 index 000000000000..85fd0289927c --- /dev/null +++ b/net/sched/act_blockcast.c @@ -0,0 +1,299 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * net/sched/act_blockcast.c Block Cast action + * Copyright (c) 2023, Mojatatu Networks + * Authors: Jamal Hadi Salim + * Victor Nogueira + * Pedro Tammela + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +static struct tc_action_ops act_blockcast_ops; + +struct tcf_blockcast_act { + struct tc_action common; +}; + +#define to_blockcast_act(a) ((struct tcf_blockcast_act *)a) + +#define TCA_ID_BLOCKCAST 123 +#define CAST_RECURSION_LIMIT 4 + +static DEFINE_PER_CPU(unsigned int, redirect_rec_level); + +static int cast_one(struct sk_buff *skb, const u32 ifindex) +{ + struct sk_buff *skb2 = skb; + int retval = TC_ACT_PIPE; + struct net_device *dev; + unsigned int rec_level; + bool expects_nh; + int mac_len; + bool at_nh; + int err; + + rec_level = __this_cpu_inc_return(redirect_rec_level); + if (unlikely(rec_level > CAST_RECURSION_LIMIT)) { + net_warn_ratelimited("blockcast: exceeded redirect recursion limit on dev %s\n", + netdev_name(skb->dev)); + __this_cpu_dec(redirect_rec_level); + return TC_ACT_SHOT; + } + + dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex); + if (unlikely(!dev)) { + __this_cpu_dec(redirect_rec_level); + return TC_ACT_SHOT; + } + + if (unlikely(!(dev->flags & IFF_UP) || !netif_carrier_ok(dev))) { + net_notice_ratelimited("blockcast: device %s is down\n", + dev->name); + __this_cpu_dec(redirect_rec_level); + return TC_ACT_SHOT; + } + + skb2 = skb_clone(skb, GFP_ATOMIC); + if (!skb2) { + __this_cpu_dec(redirect_rec_level); + return retval; + } + + nf_reset_ct(skb2); + + expects_nh = !dev_is_mac_header_xmit(dev); + at_nh = skb->data == skb_network_header(skb); + if (at_nh != expects_nh) { + mac_len = skb_at_tc_ingress(skb) ? + skb->mac_len : + skb_network_header(skb) - skb_mac_header(skb); + + if (expects_nh) { + /* target device/action expect data at nh */ + skb_pull_rcsum(skb2, mac_len); + } else { + /* target device/action expect data at mac */ + skb_push_rcsum(skb2, mac_len); + } + } + + skb2->skb_iif = skb->dev->ifindex; + skb2->dev = dev; + + err = dev_queue_xmit(skb2); + if (err) + retval = TC_ACT_SHOT; + + __this_cpu_dec(redirect_rec_level); + + return retval; +} + +TC_INDIRECT_SCOPE int tcf_blockcast_run(struct sk_buff *skb, + const struct tc_action *a, + struct tcf_result *res) +{ + u32 block_index = qdisc_skb_cb(skb)->block_index; + struct tcf_blockcast_act *p = to_blockcast_act(a); + int action = READ_ONCE(p->tcf_action); + struct net *net = dev_net(skb->dev); + struct tcf_block *block; + struct net_device *dev; + u32 exception_ifindex; + unsigned long index; + + block = tcf_block_lookup(net, block_index); + exception_ifindex = skb->dev->ifindex; + + tcf_action_update_bstats(&p->common, skb); + tcf_lastuse_update(&p->tcf_tm); + + if (!block || xa_empty(&block->ports)) + goto act_done; + + /* we are already under rcu protection, so iterating block is safe*/ + xa_for_each(&block->ports, index, dev) { + int err; + + if (index == exception_ifindex) + continue; + + err = cast_one(skb, dev->ifindex); + if (err != TC_ACT_PIPE) + printk("(%d)Failed to send to dev\t%d: %s\n", err, + dev->ifindex, dev->name); + } + +act_done: + if (action == TC_ACT_SHOT) + tcf_action_inc_drop_qstats(&p->common); + return action; +} + +static const struct nla_policy blockcast_policy[TCA_DEF_MAX + 1] = { + [TCA_DEF_PARMS] = { .len = sizeof(struct tc_defact) }, +}; + +static int tcf_blockcast_init(struct net *net, struct nlattr *nla, + struct nlattr *est, struct tc_action **a, + struct tcf_proto *tp, u32 flags, + struct netlink_ext_ack *extack) +{ + struct tc_action_net *tn = net_generic(net, act_blockcast_ops.net_id); + struct tcf_blockcast_act *p = to_blockcast_act(a); + bool bind = flags & TCA_ACT_FLAGS_BIND; + struct nlattr *tb[TCA_DEF_MAX + 1]; + struct tcf_chain *goto_ch = NULL; + struct tc_defact *parm; + bool exists = false; + int ret = 0, err; + u32 index; + + if (!nla) + return -EINVAL; + + err = nla_parse_nested_deprecated(tb, TCA_DEF_MAX, nla, + blockcast_policy, NULL); + if (err < 0) + return err; + + if (!tb[TCA_DEF_PARMS]) + return -EINVAL; + + parm = nla_data(tb[TCA_DEF_PARMS]); + index = parm->index; + + err = tcf_idr_check_alloc(tn, &index, a, bind); + if (err < 0) + return err; + + exists = err; + if (exists && bind) + return 0; + + if (!exists) { + ret = tcf_idr_create_from_flags(tn, index, est, a, + &act_blockcast_ops, bind, flags); + if (ret) { + tcf_idr_cleanup(tn, index); + return ret; + } + + ret = ACT_P_CREATED; + } else { + if (!(flags & TCA_ACT_FLAGS_REPLACE)) { + err = -EEXIST; + goto release_idr; + } + } + + err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack); + if (err < 0) + goto release_idr; + + if (exists) + spin_lock_bh(&p->tcf_lock); + goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); + if (exists) + spin_unlock_bh(&p->tcf_lock); + + if (goto_ch) + tcf_chain_put_by_act(goto_ch); + + return ret; +release_idr: + tcf_idr_release(*a, bind); + return err; +} + +static int tcf_blockcast_dump(struct sk_buff *skb, struct tc_action *a, + int bind, int ref) +{ + unsigned char *b = skb_tail_pointer(skb); + struct tcf_blockcast_act *p = to_blockcast_act(a); + struct tc_defact opt = { + .index = p->tcf_index, + .refcnt = refcount_read(&p->tcf_refcnt) - ref, + .bindcnt = atomic_read(&p->tcf_bindcnt) - bind, + }; + struct tcf_t t; + + spin_lock_bh(&p->tcf_lock); + opt.action = p->tcf_action; + if (nla_put(skb, TCA_DEF_PARMS, sizeof(opt), &opt)) + goto nla_put_failure; + + tcf_tm_dump(&t, &p->tcf_tm); + if (nla_put_64bit(skb, TCA_DEF_TM, sizeof(t), &t, TCA_DEF_PAD)) + goto nla_put_failure; + spin_unlock_bh(&p->tcf_lock); + + return skb->len; + +nla_put_failure: + spin_unlock_bh(&p->tcf_lock); + nlmsg_trim(skb, b); + return -1; +} + +static struct tc_action_ops act_blockcast_ops = { + .kind = "blockcast", + .id = TCA_ID_BLOCKCAST, + .owner = THIS_MODULE, + .act = tcf_blockcast_run, + .dump = tcf_blockcast_dump, + .init = tcf_blockcast_init, + .size = sizeof(struct tcf_blockcast_act), +}; + +static __net_init int blockcast_init_net(struct net *net) +{ + struct tc_action_net *tn = net_generic(net, act_blockcast_ops.net_id); + + return tc_action_net_init(net, tn, &act_blockcast_ops); +} + +static void __net_exit blockcast_exit_net(struct list_head *net_list) +{ + tc_action_net_exit(net_list, act_blockcast_ops.net_id); +} + +static struct pernet_operations blockcast_net_ops = { + .init = blockcast_init_net, + .exit_batch = blockcast_exit_net, + .id = &act_blockcast_ops.net_id, + .size = sizeof(struct tc_action_net), +}; + +MODULE_AUTHOR("Mojatatu Networks, Inc"); +MODULE_LICENSE("GPL"); + +static int __init blockcast_init_module(void) +{ + int ret = tcf_register_action(&act_blockcast_ops, &blockcast_net_ops); + + if (!ret) + pr_info("blockcast TC action Loaded\n"); + return ret; +} + +static void __exit blockcast_cleanup_module(void) +{ + tcf_unregister_action(&act_blockcast_ops, &blockcast_net_ops); +} +