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
105extern int rss_debug;
106
107/*
108 * Device driver interfaces to query RSS properties that must be programmed
109 * into hardware.
110 */
111u_int rss_getbits(void);
112u_int rss_getbucket(u_int hash);
113u_int rss_get_indirection_to_bucket(u_int index);
114u_int rss_getcpu(u_int bucket);
115void rss_getkey(uint8_t *key);
116u_int rss_gethashalgo(void);
117u_int rss_getnumbuckets(void);
118u_int rss_getnumcpus(void);
119u_int rss_gethashconfig(void);
120
121/*
122 * Hash calculation functions.
123 */
124uint32_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 */
129struct mbuf * rss_m2cpuid(struct mbuf *m, uintptr_t source, u_int *cpuid);
130u_int rss_hash2cpuid(uint32_t hash_val, uint32_t hash_type);
131int rss_hash2bucket(uint32_t hash_val, uint32_t hash_type,
132 uint32_t *bucket_id);
133int rss_m2bucket(struct mbuf *m, uint32_t *bucket_id);
134
135#endif /* !_NET_RSS_CONFIG_H_ */