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 <paulb@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Paul Blakey 2021-12-14 19:24:33 +02:00 committed by Jakub Kicinski
parent 8ca4090fec
commit ec624fe740
7 changed files with 34 additions and 17 deletions

View File

@ -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

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@ -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);

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@ -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);

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@ -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 @@ do_nat:
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;

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@ -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;

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@ -19,6 +19,7 @@
#include <net/sch_generic.h>
#include <net/pkt_cls.h>
#include <net/pkt_sched.h>
#include <net/ip.h>
#include <net/flow_dissector.h>
#include <net/geneve.h>
@ -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;

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@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
#include <net/netlink.h>
#include <net/sch_generic.h>
#include <net/pkt_sched.h>
#include <net/dst.h>
#include <net/ip.h>
#include <net/ip6_fib.h>
@ -137,7 +138,7 @@ err:
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)