1/*-
2 * Copyright (c) 2010-2011 Juniper Networks, Inc.
3 * All rights reserved.
4 *
5 * This software was developed by Robert N. M. Watson under contract
6 * to Juniper Networks, 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 AUTHOR 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 AUTHOR 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 *
29 * $FreeBSD$
30 */
31
32#ifndef _NET_RSS_CONFIG_H_
33#define	_NET_RSS_CONFIG_H_
34
35#include <netinet/in.h>		/* in_addr_t */
36
37/*
38 * Supported RSS hash functions.
39 */
40#define	RSS_HASH_NAIVE		0x00000001	/* Poor but fast hash. */
41#define	RSS_HASH_TOEPLITZ	0x00000002	/* Required by RSS. */
42#define	RSS_HASH_CRC32		0x00000004	/* Future; some NICs do it. */
43
44#define	RSS_HASH_MASK		(RSS_HASH_NAIVE | RSS_HASH_TOEPLITZ)
45
46/*
47 * Instances of struct inpcbinfo declare an RSS hash type indicating what
48 * header fields are covered.
49 */
50#define	RSS_HASHFIELDS_NONE		0
51#define	RSS_HASHFIELDS_4TUPLE		1
52#define	RSS_HASHFIELDS_2TUPLE		2
53
54/*
55 * Define RSS representations of the M_HASHTYPE_* values, representing
56 * which particular bits are supported.  The NICs can then use this to
57 * calculate which hash types to enable and which not to enable.
58 *
59 * The fact that these line up with M_HASHTYPE_* is not to be relied
60 * upon.
61 */
62#define	RSS_HASHTYPE_RSS_IPV4		(1 << 1)	/* IPv4 2-tuple */
63#define	RSS_HASHTYPE_RSS_TCP_IPV4	(1 << 2)	/* TCPv4 4-tuple */
64#define	RSS_HASHTYPE_RSS_IPV6		(1 << 3)	/* IPv6 2-tuple */
65#define	RSS_HASHTYPE_RSS_TCP_IPV6	(1 << 4)	/* TCPv6 4-tuple */
66#define	RSS_HASHTYPE_RSS_IPV6_EX	(1 << 5)	/* IPv6 2-tuple + ext hdrs */
67#define	RSS_HASHTYPE_RSS_TCP_IPV6_EX	(1 << 6)	/* TCPv6 4-tiple + ext hdrs */
68#define	RSS_HASHTYPE_RSS_UDP_IPV4	(1 << 7)	/* IPv4 UDP 4-tuple */
69#define	RSS_HASHTYPE_RSS_UDP_IPV4_EX	(1 << 8)	/* IPv4 UDP 4-tuple + ext hdrs */
70#define	RSS_HASHTYPE_RSS_UDP_IPV6	(1 << 9)	/* IPv6 UDP 4-tuple */
71#define	RSS_HASHTYPE_RSS_UDP_IPV6_EX	(1 << 10)	/* IPv6 UDP 4-tuple + ext hdrs */
72
73/*
74 * Compile-time limits on the size of the indirection table.
75 */
76#define	RSS_MAXBITS	7
77#define	RSS_TABLE_MAXLEN	(1 << RSS_MAXBITS)
78
79/*
80 * Maximum key size used throughout.  It's OK for hardware to use only the
81 * first 16 bytes, which is all that's required for IPv4.
82 */
83#define	RSS_KEYSIZE	40
84
85/*
86 * For RSS hash methods that do a software hash on an mbuf, the packet
87 * direction (ingress / egress) is required.
88 *
89 * The default direction (INGRESS) is the "receive into the NIC" - ie,
90 * what the hardware is hashing on.
91 */
92#define	RSS_HASH_PKT_INGRESS	0
93#define	RSS_HASH_PKT_EGRESS	1
94
95/*
96 * Rate limited debugging routines.
97 */
98#define	RSS_DEBUG(format, ...)	do {					\
99	if (rss_debug) {						\
100		static struct timeval lastfail;				\
101		static int curfail;					\
102		if (ppsratecheck(&lastfail, &curfail, 5))		\
103			printf("RSS (%s:%u): " format, __func__, __LINE__,\
104			    ##__VA_ARGS__);				\
105	}								\
106} while (0)
107
108extern int	rss_debug;
109
110/*
111 * Device driver interfaces to query RSS properties that must be programmed
112 * into hardware.
113 */
114u_int	rss_getbits(void);
115u_int	rss_getbucket(u_int hash);
116u_int	rss_get_indirection_to_bucket(u_int index);
117u_int	rss_getcpu(u_int bucket);
118void	rss_getkey(uint8_t *key);
119u_int	rss_gethashalgo(void);
120u_int	rss_getnumbuckets(void);
121u_int	rss_getnumcpus(void);
122u_int	rss_gethashconfig(void);
123
124/*
125 * Hash calculation functions.
126 */
127uint32_t	rss_hash(u_int datalen, const uint8_t *data);
128
129/*
130 * Network stack interface to query desired CPU affinity of a packet.
131 */
132struct mbuf * rss_m2cpuid(struct mbuf *m, uintptr_t source, u_int *cpuid);
133u_int	rss_hash2cpuid(uint32_t hash_val, uint32_t hash_type);
134int	rss_hash2bucket(uint32_t hash_val, uint32_t hash_type,
135	    uint32_t *bucket_id);
136int	rss_m2bucket(struct mbuf *m, uint32_t *bucket_id);
137
138#endif /* !_NET_RSS_CONFIG_H_ */
139