xref: /freebsd/sys/net/rss_config.h (revision 95ee2897e98f5d444f26ed2334cc7c439f9c16c6)
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 
30 #ifndef _NET_RSS_CONFIG_H_
31 #define	_NET_RSS_CONFIG_H_
32 
33 #include <netinet/in.h>		/* in_addr_t */
34 
35 /*
36  * Supported RSS hash functions.
37  */
38 #define	RSS_HASH_NAIVE		0x00000001	/* Poor but fast hash. */
39 #define	RSS_HASH_TOEPLITZ	0x00000002	/* Required by RSS. */
40 #define	RSS_HASH_CRC32		0x00000004	/* Future; some NICs do it. */
41 
42 #define	RSS_HASH_MASK		(RSS_HASH_NAIVE | RSS_HASH_TOEPLITZ)
43 
44 /*
45  * Instances of struct inpcbinfo declare an RSS hash type indicating what
46  * header fields are covered.
47  */
48 #define	RSS_HASHFIELDS_NONE		0
49 #define	RSS_HASHFIELDS_4TUPLE		1
50 #define	RSS_HASHFIELDS_2TUPLE		2
51 
52 /*
53  * Define RSS representations of the M_HASHTYPE_* values, representing
54  * which particular bits are supported.  The NICs can then use this to
55  * calculate which hash types to enable and which not to enable.
56  *
57  * The fact that these line up with M_HASHTYPE_* is not to be relied
58  * upon.
59  */
60 #define	RSS_HASHTYPE_RSS_IPV4		(1 << 1)	/* IPv4 2-tuple */
61 #define	RSS_HASHTYPE_RSS_TCP_IPV4	(1 << 2)	/* TCPv4 4-tuple */
62 #define	RSS_HASHTYPE_RSS_IPV6		(1 << 3)	/* IPv6 2-tuple */
63 #define	RSS_HASHTYPE_RSS_TCP_IPV6	(1 << 4)	/* TCPv6 4-tuple */
64 #define	RSS_HASHTYPE_RSS_IPV6_EX	(1 << 5)	/* IPv6 2-tuple + ext hdrs */
65 #define	RSS_HASHTYPE_RSS_TCP_IPV6_EX	(1 << 6)	/* TCPv6 4-tiple + ext hdrs */
66 #define	RSS_HASHTYPE_RSS_UDP_IPV4	(1 << 7)	/* IPv4 UDP 4-tuple */
67 #define	RSS_HASHTYPE_RSS_UDP_IPV6	(1 << 9)	/* IPv6 UDP 4-tuple */
68 #define	RSS_HASHTYPE_RSS_UDP_IPV6_EX	(1 << 10)	/* IPv6 UDP 4-tuple + ext hdrs */
69 
70 /*
71  * Compile-time limits on the size of the indirection table.
72  */
73 #define	RSS_MAXBITS	7
74 #define	RSS_TABLE_MAXLEN	(1 << RSS_MAXBITS)
75 
76 /*
77  * Maximum key size used throughout.  It's OK for hardware to use only the
78  * first 16 bytes, which is all that's required for IPv4.
79  */
80 #define	RSS_KEYSIZE	40
81 
82 /*
83  * For RSS hash methods that do a software hash on an mbuf, the packet
84  * direction (ingress / egress) is required.
85  *
86  * The default direction (INGRESS) is the "receive into the NIC" - ie,
87  * what the hardware is hashing on.
88  */
89 #define	RSS_HASH_PKT_INGRESS	0
90 #define	RSS_HASH_PKT_EGRESS	1
91 
92 /*
93  * Rate limited debugging routines.
94  */
95 #define	RSS_DEBUG(format, ...)	do {					\
96 	if (rss_debug) {						\
97 		static struct timeval lastfail;				\
98 		static int curfail;					\
99 		if (ppsratecheck(&lastfail, &curfail, 5))		\
100 			printf("RSS (%s:%u): " format, __func__, __LINE__,\
101 			    ##__VA_ARGS__);				\
102 	}								\
103 } while (0)
104 
105 extern int	rss_debug;
106 
107 /*
108  * Device driver interfaces to query RSS properties that must be programmed
109  * into hardware.
110  */
111 u_int	rss_getbits(void);
112 u_int	rss_getbucket(u_int hash);
113 u_int	rss_get_indirection_to_bucket(u_int index);
114 u_int	rss_getcpu(u_int bucket);
115 void	rss_getkey(uint8_t *key);
116 u_int	rss_gethashalgo(void);
117 u_int	rss_getnumbuckets(void);
118 u_int	rss_getnumcpus(void);
119 u_int	rss_gethashconfig(void);
120 
121 /*
122  * Hash calculation functions.
123  */
124 uint32_t	rss_hash(u_int datalen, const uint8_t *data);
125 
126 /*
127  * Network stack interface to query desired CPU affinity of a packet.
128  */
129 struct mbuf * rss_m2cpuid(struct mbuf *m, uintptr_t source, u_int *cpuid);
130 u_int	rss_hash2cpuid(uint32_t hash_val, uint32_t hash_type);
131 int	rss_hash2bucket(uint32_t hash_val, uint32_t hash_type,
132 	    uint32_t *bucket_id);
133 int	rss_m2bucket(struct mbuf *m, uint32_t *bucket_id);
134 
135 #endif /* !_NET_RSS_CONFIG_H_ */
136