1/*-
2 *
3 * SPDX-License-Identifier: BSD-3-Clause
4 *
5 * Copyright (c) 2018-2020
6 *	Netflix Inc.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 * __FBSDID("$FreeBSD$");
29 *
30 */
31/**
32 * Author: Randall Stewart <rrs@netflix.com>
33 */
34#ifndef __tcp_ratelimit_h__
35#define __tcp_ratelimit_h__
36
37struct m_snd_tag;
38
39/* Flags on an individual rate */
40#define HDWRPACE_INITED 	0x0001
41#define HDWRPACE_TAGPRESENT	0x0002
42#define HDWRPACE_IFPDEPARTED	0x0004
43struct tcp_hwrate_limit_table {
44	const struct tcp_rate_set *ptbl;	/* Pointer to parent table */
45	struct m_snd_tag *tag;	/* Send tag if needed (chelsio) */
46	long	 rate;		/* Rate we get in Bytes per second (Bps) */
47	long	 using;		/* How many flows are using this hdwr rate. */
48	long	 rs_num_enobufs;
49	uint32_t time_between;	/* Time-Gap between packets at this rate */
50	uint32_t flags;
51};
52
53/* Rateset flags */
54#define RS_IS_DEFF      0x0001	/* Its a lagg, do a double lookup */
55#define RS_IS_INTF      0x0002	/* Its a plain interface */
56#define RS_NO_PRE       0x0004	/* The interfacd has set rates */
57#define RS_INT_TBL      0x0010	/*
58				 * The table is the internal version
59				 * which has special setup requirements.
60				 */
61#define RS_IS_DEAD      0x0020	/* The RS is dead list */
62#define RS_FUNERAL_SCHD 0x0040  /* Is a epoch call scheduled to bury this guy?*/
63#define RS_INTF_NO_SUP  0x0100 	/* The interface does not support the ratelimiting */
64
65struct tcp_rate_set {
66	struct sysctl_ctx_list sysctl_ctx;
67	CK_LIST_ENTRY(tcp_rate_set) next;
68	struct ifnet *rs_ifp;
69	struct tcp_hwrate_limit_table *rs_rlt;
70	uint64_t rs_flows_using;
71	uint64_t rs_flow_limit;
72	uint32_t rs_if_dunit;
73	int rs_rate_cnt;
74	int rs_min_seg;
75	int rs_highest_valid;
76	int rs_lowest_valid;
77	int rs_disable;
78	int rs_flags;
79	struct epoch_context rs_epoch_ctx;
80};
81
82CK_LIST_HEAD(head_tcp_rate_set, tcp_rate_set);
83
84/* Request flags */
85#define RS_PACING_EXACT_MATCH	0x0001	/* Need an exact match for rate */
86#define RS_PACING_GT		0x0002	/* Greater than requested */
87#define RS_PACING_GEQ		0x0004	/* Greater than or equal too */
88#define RS_PACING_LT		0x0008	/* Less than requested rate */
89#define RS_PACING_SUB_OK	0x0010	/* If a rate can't be found get the
90					 * next best rate (highest or lowest). */
91#ifdef _KERNEL
92#ifndef ETHERNET_SEGMENT_SIZE
93#define ETHERNET_SEGMENT_SIZE 1514
94#endif
95#ifdef RATELIMIT
96#define DETAILED_RATELIMIT_SYSCTL 1	/*
97					 * Undefine this if you don't want
98					 * detailed rates to appear in
99					 * net.inet.tcp.rl.
100					 * With the defintion each rate
101					 * shows up in your sysctl tree
102					 * this can be big.
103					 */
104uint64_t inline
105tcp_hw_highest_rate(const struct tcp_hwrate_limit_table *rle)
106{
107	return (rle->ptbl->rs_rlt[rle->ptbl->rs_highest_valid].rate);
108}
109
110uint64_t
111tcp_hw_highest_rate_ifp(struct ifnet *ifp, struct inpcb *inp);
112
113const struct tcp_hwrate_limit_table *
114tcp_set_pacing_rate(struct tcpcb *tp, struct ifnet *ifp,
115    uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate);
116
117const struct tcp_hwrate_limit_table *
118tcp_chg_pacing_rate(const struct tcp_hwrate_limit_table *crte,
119    struct tcpcb *tp, struct ifnet *ifp,
120    uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate);
121void
122tcp_rel_pacing_rate(const struct tcp_hwrate_limit_table *crte,
123    struct tcpcb *tp);
124#else
125static inline const struct tcp_hwrate_limit_table *
126tcp_set_pacing_rate(struct tcpcb *tp, struct ifnet *ifp,
127    uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate)
128{
129	if (error)
130		*error = EOPNOTSUPP;
131	return (NULL);
132}
133
134static inline const struct tcp_hwrate_limit_table *
135tcp_chg_pacing_rate(const struct tcp_hwrate_limit_table *crte,
136    struct tcpcb *tp, struct ifnet *ifp,
137    uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate)
138{
139	if (error)
140		*error = EOPNOTSUPP;
141	return (NULL);
142}
143
144static inline void
145tcp_rel_pacing_rate(const struct tcp_hwrate_limit_table *crte,
146    struct tcpcb *tp)
147{
148	return;
149}
150
151static uint64_t inline
152tcp_hw_highest_rate(const struct tcp_hwrate_limit_table *rle)
153{
154	return (0);
155}
156
157static uint64_t inline
158tcp_hw_highest_rate_ifp(struct ifnet *ifp, struct inpcb *inp)
159{
160	return (0);
161}
162
163
164#endif
165/*
166 * Given a b/w and a segsiz, and optional hardware
167 * rate limit, return the ideal size to burst
168 * out at once. Note the parameter can_use_1mss
169 * dictates if the transport will tolerate a 1mss
170 * limit, if not it will bottom out at 2mss (think
171 * delayed ack).
172 */
173uint32_t
174tcp_get_pacing_burst_size(struct tcpcb *tp, uint64_t bw, uint32_t segsiz, int can_use_1mss,
175   const struct tcp_hwrate_limit_table *te, int *err);
176
177
178void
179tcp_rl_log_enobuf(const struct tcp_hwrate_limit_table *rte);
180
181#endif
182#endif
183