xref: /freebsd/sys/net/rss_config.h (revision fcb560670601b2a4d87bb31d7531c8dcc37ee71b)
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  * Device driver interfaces to query RSS properties that must be programmed
97  * into hardware.
98  */
99 u_int	rss_getbits(void);
100 u_int	rss_getbucket(u_int hash);
101 u_int	rss_get_indirection_to_bucket(u_int index);
102 u_int	rss_getcpu(u_int bucket);
103 void	rss_getkey(uint8_t *key);
104 u_int	rss_gethashalgo(void);
105 u_int	rss_getnumbuckets(void);
106 u_int	rss_getnumcpus(void);
107 u_int	rss_gethashconfig(void);
108 
109 /*
110  * Hash calculation functions.
111  */
112 uint32_t	rss_hash(u_int datalen, const uint8_t *data);
113 
114 /*
115  * Network stack interface to query desired CPU affinity of a packet.
116  */
117 struct mbuf * rss_m2cpuid(struct mbuf *m, uintptr_t source, u_int *cpuid);
118 u_int	rss_hash2cpuid(uint32_t hash_val, uint32_t hash_type);
119 int	rss_hash2bucket(uint32_t hash_val, uint32_t hash_type,
120 	    uint32_t *bucket_id);
121 int	rss_m2bucket(struct mbuf *m, uint32_t *bucket_id);
122 
123 #endif /* !_NET_RSS_CONFIG_H_ */
124