xref: /linux/include/net/pkt_sched.h (revision f055268e3946555deb9bb80b2c8c9798c64dbc47)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __NET_PKT_SCHED_H
3 #define __NET_PKT_SCHED_H
4 
5 #include <linux/jiffies.h>
6 #include <linux/ktime.h>
7 #include <linux/if_vlan.h>
8 #include <linux/netdevice.h>
9 #include <net/sch_generic.h>
10 #include <net/net_namespace.h>
11 #include <uapi/linux/pkt_sched.h>
12 
13 #define DEFAULT_TX_QUEUE_LEN	1000
14 #define STAB_SIZE_LOG_MAX	30
15 
16 struct qdisc_walker {
17 	int	stop;
18 	int	skip;
19 	int	count;
20 	int	(*fn)(struct Qdisc *, unsigned long cl, struct qdisc_walker *);
21 };
22 
23 static inline void *qdisc_priv(struct Qdisc *q)
24 {
25 	return &q->privdata;
26 }
27 
28 static inline struct Qdisc *qdisc_from_priv(void *priv)
29 {
30 	return container_of(priv, struct Qdisc, privdata);
31 }
32 
33 /*
34    Timer resolution MUST BE < 10% of min_schedulable_packet_size/bandwidth
35 
36    Normal IP packet size ~ 512byte, hence:
37 
38    0.5Kbyte/1Mbyte/sec = 0.5msec, so that we need 50usec timer for
39    10Mbit ethernet.
40 
41    10msec resolution -> <50Kbit/sec.
42 
43    The result: [34]86 is not good choice for QoS router :-(
44 
45    The things are not so bad, because we may use artificial
46    clock evaluated by integration of network data flow
47    in the most critical places.
48  */
49 
50 typedef u64	psched_time_t;
51 typedef long	psched_tdiff_t;
52 
53 /* Avoid doing 64 bit divide */
54 #define PSCHED_SHIFT			6
55 #define PSCHED_TICKS2NS(x)		((s64)(x) << PSCHED_SHIFT)
56 #define PSCHED_NS2TICKS(x)		((x) >> PSCHED_SHIFT)
57 
58 #define PSCHED_TICKS_PER_SEC		PSCHED_NS2TICKS(NSEC_PER_SEC)
59 #define PSCHED_PASTPERFECT		0
60 
61 static inline psched_time_t psched_get_time(void)
62 {
63 	return PSCHED_NS2TICKS(ktime_get_ns());
64 }
65 
66 struct qdisc_watchdog {
67 	u64		last_expires;
68 	struct hrtimer	timer;
69 	struct Qdisc	*qdisc;
70 };
71 
72 void qdisc_watchdog_init_clockid(struct qdisc_watchdog *wd, struct Qdisc *qdisc,
73 				 clockid_t clockid);
74 void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc);
75 
76 void qdisc_watchdog_schedule_range_ns(struct qdisc_watchdog *wd, u64 expires,
77 				      u64 delta_ns);
78 
79 static inline void qdisc_watchdog_schedule_ns(struct qdisc_watchdog *wd,
80 					      u64 expires)
81 {
82 	return qdisc_watchdog_schedule_range_ns(wd, expires, 0ULL);
83 }
84 
85 static inline void qdisc_watchdog_schedule(struct qdisc_watchdog *wd,
86 					   psched_time_t expires)
87 {
88 	qdisc_watchdog_schedule_ns(wd, PSCHED_TICKS2NS(expires));
89 }
90 
91 void qdisc_watchdog_cancel(struct qdisc_watchdog *wd);
92 
93 extern struct Qdisc_ops pfifo_qdisc_ops;
94 extern struct Qdisc_ops bfifo_qdisc_ops;
95 extern struct Qdisc_ops pfifo_head_drop_qdisc_ops;
96 
97 int fifo_set_limit(struct Qdisc *q, unsigned int limit);
98 struct Qdisc *fifo_create_dflt(struct Qdisc *sch, struct Qdisc_ops *ops,
99 			       unsigned int limit,
100 			       struct netlink_ext_ack *extack);
101 
102 int register_qdisc(struct Qdisc_ops *qops);
103 int unregister_qdisc(struct Qdisc_ops *qops);
104 void qdisc_get_default(char *id, size_t len);
105 int qdisc_set_default(const char *id);
106 
107 void qdisc_hash_add(struct Qdisc *q, bool invisible);
108 void qdisc_hash_del(struct Qdisc *q);
109 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle);
110 struct Qdisc *qdisc_lookup_rcu(struct net_device *dev, u32 handle);
111 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
112 					struct nlattr *tab,
113 					struct netlink_ext_ack *extack);
114 void qdisc_put_rtab(struct qdisc_rate_table *tab);
115 void qdisc_put_stab(struct qdisc_size_table *tab);
116 void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc);
117 bool sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
118 		     struct net_device *dev, struct netdev_queue *txq,
119 		     spinlock_t *root_lock, bool validate);
120 
121 void __qdisc_run(struct Qdisc *q);
122 
123 static inline void qdisc_run(struct Qdisc *q)
124 {
125 	if (qdisc_run_begin(q)) {
126 		__qdisc_run(q);
127 		qdisc_run_end(q);
128 	}
129 }
130 
131 /* Calculate maximal size of packet seen by hard_start_xmit
132    routine of this device.
133  */
134 static inline unsigned int psched_mtu(const struct net_device *dev)
135 {
136 	return dev->mtu + dev->hard_header_len;
137 }
138 
139 static inline struct net *qdisc_net(struct Qdisc *q)
140 {
141 	return dev_net(q->dev_queue->dev);
142 }
143 
144 struct tc_cbs_qopt_offload {
145 	u8 enable;
146 	s32 queue;
147 	s32 hicredit;
148 	s32 locredit;
149 	s32 idleslope;
150 	s32 sendslope;
151 };
152 
153 struct tc_etf_qopt_offload {
154 	u8 enable;
155 	s32 queue;
156 };
157 
158 struct tc_taprio_sched_entry {
159 	u8 command; /* TC_TAPRIO_CMD_* */
160 
161 	/* The gate_mask in the offloading side refers to traffic classes */
162 	u32 gate_mask;
163 	u32 interval;
164 };
165 
166 struct tc_taprio_qopt_offload {
167 	u8 enable;
168 	ktime_t base_time;
169 	u64 cycle_time;
170 	u64 cycle_time_extension;
171 
172 	size_t num_entries;
173 	struct tc_taprio_sched_entry entries[];
174 };
175 
176 #if IS_ENABLED(CONFIG_NET_SCH_TAPRIO)
177 
178 /* Reference counting */
179 struct tc_taprio_qopt_offload *taprio_offload_get(struct tc_taprio_qopt_offload
180 						  *offload);
181 void taprio_offload_free(struct tc_taprio_qopt_offload *offload);
182 
183 #else
184 
185 /* Reference counting */
186 static inline struct tc_taprio_qopt_offload *
187 taprio_offload_get(struct tc_taprio_qopt_offload *offload)
188 {
189 	return NULL;
190 }
191 
192 static inline void taprio_offload_free(struct tc_taprio_qopt_offload *offload)
193 {
194 }
195 
196 #endif
197 
198 /* Ensure skb_mstamp_ns, which might have been populated with the txtime, is
199  * not mistaken for a software timestamp, because this will otherwise prevent
200  * the dispatch of hardware timestamps to the socket.
201  */
202 static inline void skb_txtime_consumed(struct sk_buff *skb)
203 {
204 	skb->tstamp = ktime_set(0, 0);
205 }
206 
207 struct tc_skb_cb {
208 	struct qdisc_skb_cb qdisc_cb;
209 
210 	u16 mru;
211 	u8 post_ct:1;
212 	u8 post_ct_snat:1;
213 	u8 post_ct_dnat:1;
214 	u16 zone; /* Only valid if post_ct = true */
215 };
216 
217 static inline struct tc_skb_cb *tc_skb_cb(const struct sk_buff *skb)
218 {
219 	struct tc_skb_cb *cb = (struct tc_skb_cb *)skb->cb;
220 
221 	BUILD_BUG_ON(sizeof(*cb) > sizeof_field(struct sk_buff, cb));
222 	return cb;
223 }
224 
225 #endif
226