xref: /freebsd/sys/netinet/tcp_lro.h (revision f7c32ed617858bcd22f8d1b03199099d50125721)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2006, Myricom Inc.
5  * Copyright (c) 2008, Intel Corporation.
6  * Copyright (c) 2016-2021 Mellanox Technologies.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  * $FreeBSD$
31  */
32 
33 #ifndef _TCP_LRO_H_
34 #define _TCP_LRO_H_
35 
36 #include <sys/time.h>
37 
38 #ifndef TCP_LRO_ENTRIES
39 /* Define default number of LRO entries per RX queue */
40 #define	TCP_LRO_ENTRIES	8
41 #endif
42 
43 /*
44  * Flags for ACK entry for compression
45  * the bottom 8 bits has the th_flags.
46  * LRO itself adds only the TSTMP flags
47  * to indicate if either of the types
48  * of timestamps are filled and the
49  * HAS_TSTMP option to indicate if the
50  * TCP timestamp option is valid.
51  *
52  * The other 5 flag bits are for processing
53  * by a stack.
54  *
55  */
56 #define TSTMP_LRO		0x0100
57 #define TSTMP_HDWR		0x0200
58 #define HAS_TSTMP		0x0400
59 /*
60  * Default number of interrupts on the same cpu in a row
61  * that will cause us to declare a "affinity cpu".
62  */
63 #define TCP_LRO_CPU_DECLARATION_THRESH 50
64 
65 struct inpcb;
66 
67 union lro_address {
68 	u_long raw[1];
69 	struct {
70 		uint8_t lro_type;	/* internal */
71 #define	LRO_TYPE_NONE     0
72 #define	LRO_TYPE_IPV4_TCP 1
73 #define	LRO_TYPE_IPV6_TCP 2
74 #define	LRO_TYPE_IPV4_UDP 3
75 #define	LRO_TYPE_IPV6_UDP 4
76 		uint8_t lro_flags;
77 #define	LRO_FLAG_DECRYPTED 1
78 		uint16_t vlan_id;	/* VLAN identifier */
79 		uint16_t s_port;	/* source TCP/UDP port */
80 		uint16_t d_port;	/* destination TCP/UDP port */
81 		uint32_t vxlan_vni;	/* VXLAN virtual network identifier */
82 		union {
83 #ifdef INET
84 			struct in_addr v4;
85 #endif
86 #ifdef INET6
87 			struct in6_addr v6;
88 #endif
89 		} s_addr;	/* source IPv4/IPv6 address */
90 		union {
91 #ifdef INET
92 			struct in_addr v4;
93 #endif
94 #ifdef INET6
95 			struct in6_addr v6;
96 #endif
97 		} d_addr;	/* destination IPv4/IPv6 address */
98 	};
99 } __aligned(sizeof(u_long));
100 
101 #define	LRO_RAW_ADDRESS_MAX \
102     (sizeof(union lro_address) / sizeof(u_long))
103 
104 /* Optimize address comparison by comparing one unsigned long at a time: */
105 
106 static inline bool
107 lro_address_compare(const union lro_address *pa, const union lro_address *pb)
108 {
109 	if (pa->lro_type == LRO_TYPE_NONE && pb->lro_type == LRO_TYPE_NONE) {
110 		return (true);
111 	} else for (unsigned i = 0; i < LRO_RAW_ADDRESS_MAX; i++) {
112 		if (pa->raw[i] != pb->raw[i])
113 			return (false);
114 	}
115 	return (true);
116 }
117 
118 struct lro_parser {
119 	union lro_address data;
120 	union {
121 		uint8_t *l3;
122 		struct ip *ip4;
123 		struct ip6_hdr *ip6;
124 	};
125 	union {
126 		uint8_t *l4;
127 		struct tcphdr *tcp;
128 		struct udphdr *udp;
129 	};
130 	uint16_t total_hdr_len;
131 };
132 
133 /* This structure is zeroed frequently, try to keep it small. */
134 struct lro_entry {
135 	LIST_ENTRY(lro_entry)	next;
136 	LIST_ENTRY(lro_entry)	hash_next;
137 	struct mbuf		*m_head;
138 	struct mbuf		*m_tail;
139 	struct mbuf		*m_last_mbuf;
140 	struct lro_parser	outer;
141 	struct lro_parser	inner;
142 	uint32_t		next_seq;	/* tcp_seq */
143 	uint32_t		ack_seq;	/* tcp_seq */
144 	uint32_t		tsval;
145 	uint32_t		tsecr;
146 	uint16_t		compressed;
147 	uint16_t		uncompressed;
148 	uint16_t		window;
149 	uint16_t		timestamp;	/* flag, not a TCP hdr field. */
150 	struct bintime		alloc_time;	/* time when entry was allocated */
151 };
152 
153 LIST_HEAD(lro_head, lro_entry);
154 
155 struct lro_mbuf_sort {
156 	uint64_t seq;
157 	struct mbuf *mb;
158 };
159 
160 /* NB: This is part of driver structs. */
161 struct lro_ctrl {
162 	struct ifnet	*ifp;
163 	struct lro_mbuf_sort *lro_mbuf_data;
164 	struct bintime	lro_last_queue_time;	/* last time data was queued */
165 	uint64_t	lro_queued;
166 	uint64_t	lro_flushed;
167 	uint64_t	lro_bad_csum;
168 	unsigned	lro_cnt;
169 	unsigned	lro_mbuf_count;
170 	unsigned	lro_mbuf_max;
171 	unsigned short	lro_ackcnt_lim;		/* max # of aggregated ACKs */
172 	unsigned short	lro_cpu;		/* Guess at the cpu we have affinity too */
173 	unsigned 	lro_length_lim;		/* max len of aggregated data */
174 	u_long		lro_hashsz;
175 	uint32_t	lro_last_cpu;
176 	uint32_t 	lro_cnt_of_same_cpu;
177 	struct lro_head	*lro_hash;
178 	struct lro_head	lro_active;
179 	struct lro_head	lro_free;
180 	uint8_t		lro_cpu_is_set;		/* Flag to say its ok to set the CPU on the inp */
181 };
182 
183 struct tcp_ackent {
184 	uint64_t timestamp;	/* hardware or sofware timestamp, valid if TSTMP_LRO or TSTMP_HDRW set */
185 	uint32_t seq;		/* th_seq value */
186 	uint32_t ack;		/* th_ack value */
187 	uint32_t ts_value;	/* If ts option value, valid if HAS_TSTMP is set */
188 	uint32_t ts_echo;	/* If ts option echo, valid if HAS_TSTMP is set */
189 	uint16_t win;		/* TCP window */
190 	uint16_t flags;		/* Flags to say if TS is present and type of timestamp and th_flags */
191 	uint8_t  codepoint;	/* IP level codepoint including ECN bits */
192 	uint8_t  ack_val_set;	/* Classification of ack used by the stack */
193 	uint8_t  pad[2];	/* To 32 byte boundary */
194 };
195 
196 /* We use two M_PROTO on the mbuf */
197 #define M_ACKCMP	M_PROTO4   /* Indicates LRO is sending in a  Ack-compression mbuf */
198 #define M_LRO_EHDRSTRP	M_PROTO6   /* Indicates that LRO has stripped the etherenet header */
199 
200 #define	TCP_LRO_LENGTH_MAX	(65535 - 255)	/* safe value with room for outer headers */
201 #define	TCP_LRO_ACKCNT_MAX	65535		/* unlimited */
202 
203 int tcp_lro_init(struct lro_ctrl *);
204 int tcp_lro_init_args(struct lro_ctrl *, struct ifnet *, unsigned, unsigned);
205 void tcp_lro_free(struct lro_ctrl *);
206 void tcp_lro_flush_inactive(struct lro_ctrl *, const struct timeval *);
207 void tcp_lro_flush(struct lro_ctrl *, struct lro_entry *);
208 void tcp_lro_flush_all(struct lro_ctrl *);
209 int tcp_lro_rx(struct lro_ctrl *, struct mbuf *, uint32_t);
210 void tcp_lro_queue_mbuf(struct lro_ctrl *, struct mbuf *);
211 void tcp_lro_reg_mbufq(void);
212 void tcp_lro_dereg_mbufq(void);
213 
214 #define	TCP_LRO_NO_ENTRIES	-2
215 #define	TCP_LRO_CANNOT		-1
216 #define	TCP_LRO_NOT_SUPPORTED	1
217 
218 #endif /* _TCP_LRO_H_ */
219