Refactor / restructure the RSS code into generic, IPv4 and IPv6 specific

bits.

The motivation here is to eventually teach netisr and potentially
other networking subsystems a bit more about how RSS work queues / buckets
are configured so things have a hope of auto-configuring in the future.

* net/rss_config.[ch] takes care of the generic bits for doing
  configuration, hash function selection, etc;
* topelitz.[ch] is now in net/ rather than netinet/;
* (and would be in libkern if it didn't directly include RSS_KEYSIZE;
  that's a later thing to fix up.)
* netinet/in_rss.[ch] now just contains the IPv4 specific methods;
* and netinet/in6_rss.[ch] now just contains the IPv6 specific methods.

This should have no functional impact on anyone currently using
the RSS support.

Differential Revision:	D1383
Reviewed by:	gnn, jfv (intel driver bits)

1 files changed, 123 insertions, 0 deletions

diff --git a/sys/net/rss_config.h b/sys/net/rss_config.h
new file mode 100644
index 0000000..37d82ae
--- /dev/null
+++ b/sys/net/rss_config.h
@@ -0,0 +1,123 @@
+/*-
+ * Copyright (c) 2010-2011 Juniper Networks, Inc.
+ * All rights reserved.
+ *
+ * This software was developed by Robert N. M. Watson under contract
+ * to Juniper Networks, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _NET_RSS_CONFIG_H_
+#define	_NET_RSS_CONFIG_H_
+
+#include <netinet/in.h>		/* in_addr_t */
+
+/*
+ * Supported RSS hash functions.
+ */
+#define	RSS_HASH_NAIVE		0x00000001	/* Poor but fast hash. */
+#define	RSS_HASH_TOEPLITZ	0x00000002	/* Required by RSS. */
+#define	RSS_HASH_CRC32		0x00000004	/* Future; some NICs do it. */
+
+#define	RSS_HASH_MASK		(RSS_HASH_NAIVE | RSS_HASH_TOEPLITZ)
+
+/*
+ * Instances of struct inpcbinfo declare an RSS hash type indicating what
+ * header fields are covered.
+ */
+#define	RSS_HASHFIELDS_NONE		0
+#define	RSS_HASHFIELDS_4TUPLE		1
+#define	RSS_HASHFIELDS_2TUPLE		2
+
+/*
+ * Define RSS representations of the M_HASHTYPE_* values, representing
+ * which particular bits are supported.  The NICs can then use this to
+ * calculate which hash types to enable and which not to enable.
+ *
+ * The fact that these line up with M_HASHTYPE_* is not to be relied
+ * upon.
+ */
+#define	RSS_HASHTYPE_RSS_IPV4		(1 << 1)	/* IPv4 2-tuple */
+#define	RSS_HASHTYPE_RSS_TCP_IPV4	(1 << 2)	/* TCPv4 4-tuple */
+#define	RSS_HASHTYPE_RSS_IPV6		(1 << 3)	/* IPv6 2-tuple */
+#define	RSS_HASHTYPE_RSS_TCP_IPV6	(1 << 4)	/* TCPv6 4-tuple */
+#define	RSS_HASHTYPE_RSS_IPV6_EX	(1 << 5)	/* IPv6 2-tuple + ext hdrs */
+#define	RSS_HASHTYPE_RSS_TCP_IPV6_EX	(1 << 6)	/* TCPv6 4-tiple + ext hdrs */
+#define	RSS_HASHTYPE_RSS_UDP_IPV4	(1 << 7)	/* IPv4 UDP 4-tuple */
+#define	RSS_HASHTYPE_RSS_UDP_IPV4_EX	(1 << 8)	/* IPv4 UDP 4-tuple + ext hdrs */
+#define	RSS_HASHTYPE_RSS_UDP_IPV6	(1 << 9)	/* IPv6 UDP 4-tuple */
+#define	RSS_HASHTYPE_RSS_UDP_IPV6_EX	(1 << 10)	/* IPv6 UDP 4-tuple + ext hdrs */
+
+/*
+ * Compile-time limits on the size of the indirection table.
+ */
+#define	RSS_MAXBITS	7
+#define	RSS_TABLE_MAXLEN	(1 << RSS_MAXBITS)
+
+/*
+ * Maximum key size used throughout.  It's OK for hardware to use only the
+ * first 16 bytes, which is all that's required for IPv4.
+ */
+#define	RSS_KEYSIZE	40
+
+/*
+ * For RSS hash methods that do a software hash on an mbuf, the packet
+ * direction (ingress / egress) is required.
+ *
+ * The default direction (INGRESS) is the "receive into the NIC" - ie,
+ * what the hardware is hashing on.
+ */
+#define	RSS_HASH_PKT_INGRESS	0
+#define	RSS_HASH_PKT_EGRESS	1
+
+/*
+ * Device driver interfaces to query RSS properties that must be programmed
+ * into hardware.
+ */
+u_int	rss_getbits(void);
+u_int	rss_getbucket(u_int hash);
+u_int	rss_get_indirection_to_bucket(u_int index);
+u_int	rss_getcpu(u_int bucket);
+void	rss_getkey(uint8_t *key);
+u_int	rss_gethashalgo(void);
+u_int	rss_getnumbuckets(void);
+u_int	rss_getnumcpus(void);
+u_int	rss_gethashconfig(void);
+
+/*
+ * Hash calculation functions.
+ */
+uint32_t	rss_hash(u_int datalen, const uint8_t *data);
+
+/*
+ * Network stack interface to query desired CPU affinity of a packet.
+ */
+struct mbuf * rss_m2cpuid(struct mbuf *m, uintptr_t source, u_int *cpuid);
+u_int	rss_hash2cpuid(uint32_t hash_val, uint32_t hash_type);
+int	rss_hash2bucket(uint32_t hash_val, uint32_t hash_type,
+	    uint32_t *bucket_id);
+int	rss_m2bucket(struct mbuf *m, uint32_t *bucket_id);
+
+#endif /* !_NET_RSS_CONFIG_H_ */