From ec624fe740b416fb68d536b37fb8eef46f90b5c2 Mon Sep 17 00:00:00 2001 From: Paul Blakey Date: Tue, 14 Dec 2021 19:24:33 +0200 Subject: [PATCH] net/sched: Extend qdisc control block with tc control block BPF layer extends the qdisc control block via struct bpf_skb_data_end and because of that there is no more room to add variables to the qdisc layer control block without going over the skb->cb size. Extend the qdisc control block with a tc control block, and move all tc related variables to there as a pre-step for extending the tc control block with additional members. Signed-off-by: Paul Blakey Signed-off-by: Jakub Kicinski --- include/net/pkt_sched.h | 15 +++++++++++++++ include/net/sch_generic.h | 2 -- net/core/dev.c | 8 ++++---- net/sched/act_ct.c | 14 +++++++------- net/sched/cls_api.c | 6 ++++-- net/sched/cls_flower.c | 3 ++- net/sched/sch_frag.c | 3 ++- 7 files changed, 34 insertions(+), 17 deletions(-) diff --git a/include/net/pkt_sched.h b/include/net/pkt_sched.h index bf79f3a890af..05f18e81f3e8 100644 --- a/include/net/pkt_sched.h +++ b/include/net/pkt_sched.h @@ -193,4 +193,19 @@ static inline void skb_txtime_consumed(struct sk_buff *skb) skb->tstamp = ktime_set(0, 0); } +struct tc_skb_cb { + struct qdisc_skb_cb qdisc_cb; + + u16 mru; + bool post_ct; +}; + +static inline struct tc_skb_cb *tc_skb_cb(const struct sk_buff *skb) +{ + struct tc_skb_cb *cb = (struct tc_skb_cb *)skb->cb; + + BUILD_BUG_ON(sizeof(*cb) > sizeof_field(struct sk_buff, cb)); + return cb; +} + #endif diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index 22179b2fda72..c70e6d2b2fdd 100644 --- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -447,8 +447,6 @@ struct qdisc_skb_cb { }; #define QDISC_CB_PRIV_LEN 20 unsigned char data[QDISC_CB_PRIV_LEN]; - u16 mru; - bool post_ct; }; typedef void tcf_chain_head_change_t(struct tcf_proto *tp_head, void *priv); diff --git a/net/core/dev.c b/net/core/dev.c index 2a352e668d10..c4708e2487fb 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3941,8 +3941,8 @@ sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev) return skb; /* qdisc_skb_cb(skb)->pkt_len was already set by the caller. */ - qdisc_skb_cb(skb)->mru = 0; - qdisc_skb_cb(skb)->post_ct = false; + tc_skb_cb(skb)->mru = 0; + tc_skb_cb(skb)->post_ct = false; mini_qdisc_bstats_cpu_update(miniq, skb); switch (tcf_classify(skb, miniq->block, miniq->filter_list, &cl_res, false)) { @@ -5103,8 +5103,8 @@ sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, } qdisc_skb_cb(skb)->pkt_len = skb->len; - qdisc_skb_cb(skb)->mru = 0; - qdisc_skb_cb(skb)->post_ct = false; + tc_skb_cb(skb)->mru = 0; + tc_skb_cb(skb)->post_ct = false; skb->tc_at_ingress = 1; mini_qdisc_bstats_cpu_update(miniq, skb); diff --git a/net/sched/act_ct.c b/net/sched/act_ct.c index 90866ae45573..98e248b9c0b1 100644 --- a/net/sched/act_ct.c +++ b/net/sched/act_ct.c @@ -690,10 +690,10 @@ static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, u8 family, u16 zone, bool *defrag) { enum ip_conntrack_info ctinfo; - struct qdisc_skb_cb cb; struct nf_conn *ct; int err = 0; bool frag; + u16 mru; /* Previously seen (loopback)? Ignore. */ ct = nf_ct_get(skb, &ctinfo); @@ -708,7 +708,7 @@ static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, return err; skb_get(skb); - cb = *qdisc_skb_cb(skb); + mru = tc_skb_cb(skb)->mru; if (family == NFPROTO_IPV4) { enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone; @@ -722,7 +722,7 @@ static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, if (!err) { *defrag = true; - cb.mru = IPCB(skb)->frag_max_size; + mru = IPCB(skb)->frag_max_size; } } else { /* NFPROTO_IPV6 */ #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) @@ -735,7 +735,7 @@ static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, if (!err) { *defrag = true; - cb.mru = IP6CB(skb)->frag_max_size; + mru = IP6CB(skb)->frag_max_size; } #else err = -EOPNOTSUPP; @@ -744,7 +744,7 @@ static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, } if (err != -EINPROGRESS) - *qdisc_skb_cb(skb) = cb; + tc_skb_cb(skb)->mru = mru; skb_clear_hash(skb); skb->ignore_df = 1; return err; @@ -963,7 +963,7 @@ static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a, tcf_action_update_bstats(&c->common, skb); if (clear) { - qdisc_skb_cb(skb)->post_ct = false; + tc_skb_cb(skb)->post_ct = false; ct = nf_ct_get(skb, &ctinfo); if (ct) { nf_conntrack_put(&ct->ct_general); @@ -1048,7 +1048,7 @@ static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a, out_push: skb_push_rcsum(skb, nh_ofs); - qdisc_skb_cb(skb)->post_ct = true; + tc_skb_cb(skb)->post_ct = true; out_clear: if (defrag) qdisc_skb_cb(skb)->pkt_len = skb->len; diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c index e54f0a42270c..ff8a9383bf1c 100644 --- a/net/sched/cls_api.c +++ b/net/sched/cls_api.c @@ -1617,12 +1617,14 @@ int tcf_classify(struct sk_buff *skb, /* If we missed on some chain */ if (ret == TC_ACT_UNSPEC && last_executed_chain) { + struct tc_skb_cb *cb = tc_skb_cb(skb); + ext = tc_skb_ext_alloc(skb); if (WARN_ON_ONCE(!ext)) return TC_ACT_SHOT; ext->chain = last_executed_chain; - ext->mru = qdisc_skb_cb(skb)->mru; - ext->post_ct = qdisc_skb_cb(skb)->post_ct; + ext->mru = cb->mru; + ext->post_ct = cb->post_ct; } return ret; diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index aab13ba11767..9782b93db1b3 100644 --- a/net/sched/cls_flower.c +++ b/net/sched/cls_flower.c @@ -19,6 +19,7 @@ #include #include +#include #include #include #include @@ -309,7 +310,7 @@ static int fl_classify(struct sk_buff *skb, const struct tcf_proto *tp, struct tcf_result *res) { struct cls_fl_head *head = rcu_dereference_bh(tp->root); - bool post_ct = qdisc_skb_cb(skb)->post_ct; + bool post_ct = tc_skb_cb(skb)->post_ct; struct fl_flow_key skb_key; struct fl_flow_mask *mask; struct cls_fl_filter *f; diff --git a/net/sched/sch_frag.c b/net/sched/sch_frag.c index 8c06381391d6..5ded4c8672a6 100644 --- a/net/sched/sch_frag.c +++ b/net/sched/sch_frag.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB #include #include +#include #include #include #include @@ -137,7 +138,7 @@ static int sch_fragment(struct net *net, struct sk_buff *skb, int sch_frag_xmit_hook(struct sk_buff *skb, int (*xmit)(struct sk_buff *skb)) { - u16 mru = qdisc_skb_cb(skb)->mru; + u16 mru = tc_skb_cb(skb)->mru; int err; if (mru && skb->len > mru + skb->dev->hard_header_len)