1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* Copyright (c) 2023 Isovalent */
3 #ifndef __NET_TCX_H
4 #define __NET_TCX_H
5
6 #include <linux/bpf.h>
7 #include <linux/bpf_mprog.h>
8
9 #include <net/sch_generic.h>
10
11 struct mini_Qdisc;
12
13 struct tcx_entry {
14 struct mini_Qdisc __rcu *miniq;
15 struct bpf_mprog_bundle bundle;
16 bool miniq_active;
17 struct rcu_head rcu;
18 };
19
20 struct tcx_link {
21 struct bpf_link link;
22 struct net_device *dev;
23 u32 location;
24 };
25
tcx_set_ingress(struct sk_buff * skb,bool ingress)26 static inline void tcx_set_ingress(struct sk_buff *skb, bool ingress)
27 {
28 #ifdef CONFIG_NET_XGRESS
29 skb->tc_at_ingress = ingress;
30 #endif
31 }
32
33 #ifdef CONFIG_NET_XGRESS
tcx_entry(struct bpf_mprog_entry * entry)34 static inline struct tcx_entry *tcx_entry(struct bpf_mprog_entry *entry)
35 {
36 struct bpf_mprog_bundle *bundle = entry->parent;
37
38 return container_of(bundle, struct tcx_entry, bundle);
39 }
40
tcx_link(const struct bpf_link * link)41 static inline struct tcx_link *tcx_link(const struct bpf_link *link)
42 {
43 return container_of(link, struct tcx_link, link);
44 }
45
46 void tcx_inc(void);
47 void tcx_dec(void);
48
tcx_entry_sync(void)49 static inline void tcx_entry_sync(void)
50 {
51 /* bpf_mprog_entry got a/b swapped, therefore ensure that
52 * there are no inflight users on the old one anymore.
53 */
54 synchronize_rcu();
55 }
56
57 static inline void
tcx_entry_update(struct net_device * dev,struct bpf_mprog_entry * entry,bool ingress)58 tcx_entry_update(struct net_device *dev, struct bpf_mprog_entry *entry,
59 bool ingress)
60 {
61 ASSERT_RTNL();
62 if (ingress)
63 rcu_assign_pointer(dev->tcx_ingress, entry);
64 else
65 rcu_assign_pointer(dev->tcx_egress, entry);
66 }
67
68 static inline struct bpf_mprog_entry *
tcx_entry_fetch(struct net_device * dev,bool ingress)69 tcx_entry_fetch(struct net_device *dev, bool ingress)
70 {
71 ASSERT_RTNL();
72 if (ingress)
73 return rcu_dereference_rtnl(dev->tcx_ingress);
74 else
75 return rcu_dereference_rtnl(dev->tcx_egress);
76 }
77
tcx_entry_create(void)78 static inline struct bpf_mprog_entry *tcx_entry_create(void)
79 {
80 struct tcx_entry *tcx = kzalloc(sizeof(*tcx), GFP_KERNEL);
81
82 if (tcx) {
83 bpf_mprog_bundle_init(&tcx->bundle);
84 return &tcx->bundle.a;
85 }
86 return NULL;
87 }
88
tcx_entry_free(struct bpf_mprog_entry * entry)89 static inline void tcx_entry_free(struct bpf_mprog_entry *entry)
90 {
91 kfree_rcu(tcx_entry(entry), rcu);
92 }
93
94 static inline struct bpf_mprog_entry *
tcx_entry_fetch_or_create(struct net_device * dev,bool ingress,bool * created)95 tcx_entry_fetch_or_create(struct net_device *dev, bool ingress, bool *created)
96 {
97 struct bpf_mprog_entry *entry = tcx_entry_fetch(dev, ingress);
98
99 *created = false;
100 if (!entry) {
101 entry = tcx_entry_create();
102 if (!entry)
103 return NULL;
104 *created = true;
105 }
106 return entry;
107 }
108
tcx_skeys_inc(bool ingress)109 static inline void tcx_skeys_inc(bool ingress)
110 {
111 tcx_inc();
112 if (ingress)
113 net_inc_ingress_queue();
114 else
115 net_inc_egress_queue();
116 }
117
tcx_skeys_dec(bool ingress)118 static inline void tcx_skeys_dec(bool ingress)
119 {
120 if (ingress)
121 net_dec_ingress_queue();
122 else
123 net_dec_egress_queue();
124 tcx_dec();
125 }
126
tcx_miniq_set_active(struct bpf_mprog_entry * entry,const bool active)127 static inline void tcx_miniq_set_active(struct bpf_mprog_entry *entry,
128 const bool active)
129 {
130 ASSERT_RTNL();
131 tcx_entry(entry)->miniq_active = active;
132 }
133
tcx_entry_is_active(struct bpf_mprog_entry * entry)134 static inline bool tcx_entry_is_active(struct bpf_mprog_entry *entry)
135 {
136 ASSERT_RTNL();
137 return bpf_mprog_total(entry) || tcx_entry(entry)->miniq_active;
138 }
139
tcx_action_code(struct sk_buff * skb,int code)140 static inline enum tcx_action_base tcx_action_code(struct sk_buff *skb,
141 int code)
142 {
143 switch (code) {
144 case TCX_PASS:
145 skb->tc_index = qdisc_skb_cb(skb)->tc_classid;
146 fallthrough;
147 case TCX_DROP:
148 case TCX_REDIRECT:
149 return code;
150 case TCX_NEXT:
151 default:
152 return TCX_NEXT;
153 }
154 }
155 #endif /* CONFIG_NET_XGRESS */
156
157 #if defined(CONFIG_NET_XGRESS) && defined(CONFIG_BPF_SYSCALL)
158 int tcx_prog_attach(const union bpf_attr *attr, struct bpf_prog *prog);
159 int tcx_link_attach(const union bpf_attr *attr, struct bpf_prog *prog);
160 int tcx_prog_detach(const union bpf_attr *attr, struct bpf_prog *prog);
161 void tcx_uninstall(struct net_device *dev, bool ingress);
162
163 int tcx_prog_query(const union bpf_attr *attr,
164 union bpf_attr __user *uattr);
165
dev_tcx_uninstall(struct net_device * dev)166 static inline void dev_tcx_uninstall(struct net_device *dev)
167 {
168 ASSERT_RTNL();
169 tcx_uninstall(dev, true);
170 tcx_uninstall(dev, false);
171 }
172 #else
tcx_prog_attach(const union bpf_attr * attr,struct bpf_prog * prog)173 static inline int tcx_prog_attach(const union bpf_attr *attr,
174 struct bpf_prog *prog)
175 {
176 return -EINVAL;
177 }
178
tcx_link_attach(const union bpf_attr * attr,struct bpf_prog * prog)179 static inline int tcx_link_attach(const union bpf_attr *attr,
180 struct bpf_prog *prog)
181 {
182 return -EINVAL;
183 }
184
tcx_prog_detach(const union bpf_attr * attr,struct bpf_prog * prog)185 static inline int tcx_prog_detach(const union bpf_attr *attr,
186 struct bpf_prog *prog)
187 {
188 return -EINVAL;
189 }
190
tcx_prog_query(const union bpf_attr * attr,union bpf_attr __user * uattr)191 static inline int tcx_prog_query(const union bpf_attr *attr,
192 union bpf_attr __user *uattr)
193 {
194 return -EINVAL;
195 }
196
dev_tcx_uninstall(struct net_device * dev)197 static inline void dev_tcx_uninstall(struct net_device *dev)
198 {
199 }
200 #endif /* CONFIG_NET_XGRESS && CONFIG_BPF_SYSCALL */
201 #endif /* __NET_TCX_H */
202