xref: /freebsd/sys/netinet/tcp_lro.h (revision 79ac3c12a714bcd3f2354c52d948aed9575c46d6)
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 struct inpcb;
61 
62 union lro_address {
63 	u_long raw[1];
64 	struct {
65 		uint16_t lro_type;	/* internal */
66 #define	LRO_TYPE_NONE     0
67 #define	LRO_TYPE_IPV4_TCP 1
68 #define	LRO_TYPE_IPV6_TCP 2
69 #define	LRO_TYPE_IPV4_UDP 3
70 #define	LRO_TYPE_IPV6_UDP 4
71 		uint16_t vlan_id;	/* VLAN identifier */
72 		uint16_t s_port;	/* source TCP/UDP port */
73 		uint16_t d_port;	/* destination TCP/UDP port */
74 		uint32_t vxlan_vni;	/* VXLAN virtual network identifier */
75 		union {
76 #ifdef INET
77 			struct in_addr v4;
78 #endif
79 #ifdef INET6
80 			struct in6_addr v6;
81 #endif
82 		} s_addr;	/* source IPv4/IPv6 address */
83 		union {
84 #ifdef INET
85 			struct in_addr v4;
86 #endif
87 #ifdef INET6
88 			struct in6_addr v6;
89 #endif
90 		} d_addr;	/* destination IPv4/IPv6 address */
91 	};
92 } __aligned(sizeof(u_long));
93 
94 #define	LRO_RAW_ADDRESS_MAX \
95     (sizeof(union lro_address) / sizeof(u_long))
96 
97 /* Optimize address comparison by comparing one unsigned long at a time: */
98 
99 static inline bool
100 lro_address_compare(const union lro_address *pa, const union lro_address *pb)
101 {
102 	if (pa->lro_type == LRO_TYPE_NONE && pb->lro_type == LRO_TYPE_NONE) {
103 		return (true);
104 	} else for (unsigned i = 0; i < LRO_RAW_ADDRESS_MAX; i++) {
105 		if (pa->raw[i] != pb->raw[i])
106 			return (false);
107 	}
108 	return (true);
109 }
110 
111 struct lro_parser {
112 	union lro_address data;
113 	union {
114 		uint8_t *l3;
115 		struct ip *ip4;
116 		struct ip6_hdr *ip6;
117 	};
118 	union {
119 		uint8_t *l4;
120 		struct tcphdr *tcp;
121 		struct udphdr *udp;
122 	};
123 	uint16_t total_hdr_len;
124 };
125 
126 /* This structure is zeroed frequently, try to keep it small. */
127 struct lro_entry {
128 	LIST_ENTRY(lro_entry)	next;
129 	LIST_ENTRY(lro_entry)	hash_next;
130 	struct mbuf		*m_head;
131 	struct mbuf		*m_tail;
132 	struct mbuf		*m_last_mbuf;
133 	struct lro_parser	outer;
134 	struct lro_parser	inner;
135 	uint32_t		next_seq;	/* tcp_seq */
136 	uint32_t		ack_seq;	/* tcp_seq */
137 	uint32_t		tsval;
138 	uint32_t		tsecr;
139 	uint16_t		compressed;
140 	uint16_t		uncompressed;
141 	uint16_t		window;
142 	uint16_t		timestamp;	/* flag, not a TCP hdr field. */
143 	struct bintime		alloc_time;	/* time when entry was allocated */
144 };
145 
146 LIST_HEAD(lro_head, lro_entry);
147 
148 struct lro_mbuf_sort {
149 	uint64_t seq;
150 	struct mbuf *mb;
151 };
152 
153 /* NB: This is part of driver structs. */
154 struct lro_ctrl {
155 	struct ifnet	*ifp;
156 	struct lro_mbuf_sort *lro_mbuf_data;
157 	struct bintime	lro_last_queue_time;	/* last time data was queued */
158 	uint64_t	lro_queued;
159 	uint64_t	lro_flushed;
160 	uint64_t	lro_bad_csum;
161 	unsigned	lro_cnt;
162 	unsigned	lro_mbuf_count;
163 	unsigned	lro_mbuf_max;
164 	unsigned short	lro_ackcnt_lim;		/* max # of aggregated ACKs */
165 	unsigned 	lro_length_lim;		/* max len of aggregated data */
166 
167 	u_long		lro_hashsz;
168 	struct lro_head	*lro_hash;
169 	struct lro_head	lro_active;
170 	struct lro_head	lro_free;
171 };
172 
173 struct tcp_ackent {
174 	uint64_t timestamp;	/* hardware or sofware timestamp, valid if TSTMP_LRO or TSTMP_HDRW set */
175 	uint32_t seq;		/* th_seq value */
176 	uint32_t ack;		/* th_ack value */
177 	uint32_t ts_value;	/* If ts option value, valid if HAS_TSTMP is set */
178 	uint32_t ts_echo;	/* If ts option echo, valid if HAS_TSTMP is set */
179 	uint16_t win;		/* TCP window */
180 	uint16_t flags;		/* Flags to say if TS is present and type of timestamp and th_flags */
181 	uint8_t  codepoint;	/* IP level codepoint including ECN bits */
182 	uint8_t  ack_val_set;	/* Classification of ack used by the stack */
183 	uint8_t  pad[2];	/* To 32 byte boundary */
184 };
185 
186 /* We use two M_PROTO on the mbuf */
187 #define M_ACKCMP	M_PROTO4   /* Indicates LRO is sending in a  Ack-compression mbuf */
188 #define M_LRO_EHDRSTRP	M_PROTO6   /* Indicates that LRO has stripped the etherenet header */
189 
190 #define	TCP_LRO_LENGTH_MAX	(65535 - 255)	/* safe value with room for outer headers */
191 #define	TCP_LRO_ACKCNT_MAX	65535		/* unlimited */
192 
193 int tcp_lro_init(struct lro_ctrl *);
194 int tcp_lro_init_args(struct lro_ctrl *, struct ifnet *, unsigned, unsigned);
195 void tcp_lro_free(struct lro_ctrl *);
196 void tcp_lro_flush_inactive(struct lro_ctrl *, const struct timeval *);
197 void tcp_lro_flush(struct lro_ctrl *, struct lro_entry *);
198 void tcp_lro_flush_all(struct lro_ctrl *);
199 int tcp_lro_rx(struct lro_ctrl *, struct mbuf *, uint32_t);
200 void tcp_lro_queue_mbuf(struct lro_ctrl *, struct mbuf *);
201 void tcp_lro_reg_mbufq(void);
202 void tcp_lro_dereg_mbufq(void);
203 
204 #define	TCP_LRO_NO_ENTRIES	-2
205 #define	TCP_LRO_CANNOT		-1
206 #define	TCP_LRO_NOT_SUPPORTED	1
207 
208 #endif /* _TCP_LRO_H_ */
209