xref: /freebsd/sys/dev/cxgbe/t4_l2t.h (revision b71a5db306ab1ad1e23c7f9e3c949c6218f43455)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2011 Chelsio Communications, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  *
30  */
31 
32 #ifndef __T4_L2T_H
33 #define __T4_L2T_H
34 
35 /* identifies sync vs async L2T_WRITE_REQs */
36 #define S_SYNC_WR    12
37 #define V_SYNC_WR(x) ((x) << S_SYNC_WR)
38 #define F_SYNC_WR    V_SYNC_WR(1)
39 
40 enum { L2T_SIZE = 4096 };     /* # of L2T entries */
41 
42 enum {
43 	L2T_STATE_VALID,	/* entry is up to date */
44 	L2T_STATE_STALE,	/* entry may be used but needs revalidation */
45 	L2T_STATE_RESOLVING,	/* entry needs address resolution */
46 	L2T_STATE_FAILED,	/* failed to resolve */
47 	L2T_STATE_SYNC_WRITE,	/* synchronous write of entry underway */
48 
49 	/* when state is one of the below the entry is not hashed */
50 	L2T_STATE_SWITCHING,	/* entry is being used by a switching filter */
51 	L2T_STATE_UNUSED	/* entry not in use */
52 };
53 
54 /*
55  * Each L2T entry plays multiple roles.  First of all, it keeps state for the
56  * corresponding entry of the HW L2 table and maintains a queue of offload
57  * packets awaiting address resolution.  Second, it is a node of a hash table
58  * chain, where the nodes of the chain are linked together through their next
59  * pointer.  Finally, each node is a bucket of a hash table, pointing to the
60  * first element in its chain through its first pointer.
61  */
62 struct l2t_entry {
63 	uint16_t state;			/* entry state */
64 	uint16_t idx;			/* entry index */
65 	uint32_t addr[4];		/* next hop IP or IPv6 address */
66 	uint32_t iqid;			/* iqid for reply to write_l2e */
67 	struct sge_wrq *wrq;		/* queue to use for write_l2e */
68 	struct ifnet *ifp;		/* outgoing interface */
69 	uint16_t smt_idx;		/* SMT index */
70 	uint16_t vlan;			/* VLAN TCI (id: 0-11, prio: 13-15) */
71 	struct l2t_entry *first;	/* start of hash chain */
72 	struct l2t_entry *next;		/* next l2t_entry on chain */
73 	STAILQ_HEAD(, wrqe) wr_list;	/* list of WRs awaiting resolution */
74 	struct mtx lock;
75 	volatile int refcnt;		/* entry reference count */
76 	uint16_t hash;			/* hash bucket the entry is on */
77 	uint8_t ipv6;			/* entry is for an IPv6 address */
78 	uint8_t lport;			/* associated offload logical port */
79 	uint8_t dmac[ETHER_ADDR_LEN];	/* next hop's MAC address */
80 };
81 
82 struct l2t_data {
83 	struct rwlock lock;
84 	u_int l2t_size;
85 	volatile int nfree;	/* number of free entries */
86 	struct l2t_entry *rover;/* starting point for next allocation */
87 	struct l2t_entry l2tab[];
88 };
89 
90 
91 int t4_init_l2t(struct adapter *, int);
92 int t4_free_l2t(struct l2t_data *);
93 struct l2t_entry *t4_alloc_l2e(struct l2t_data *);
94 struct l2t_entry *t4_l2t_alloc_switching(struct l2t_data *);
95 int t4_l2t_set_switching(struct adapter *, struct l2t_entry *, uint16_t,
96     uint8_t, uint8_t *);
97 int t4_write_l2e(struct l2t_entry *, int);
98 int do_l2t_write_rpl(struct sge_iq *, const struct rss_header *, struct mbuf *);
99 
100 static inline void
101 t4_l2t_release(struct l2t_entry *e)
102 {
103 	struct l2t_data *d = __containerof(e, struct l2t_data, l2tab[e->idx]);
104 
105 	if (atomic_fetchadd_int(&e->refcnt, -1) == 1)
106 		atomic_add_int(&d->nfree, 1);
107 }
108 
109 
110 #ifdef SBUF_DRAIN
111 int sysctl_l2t(SYSCTL_HANDLER_ARGS);
112 #endif
113 
114 #endif  /* __T4_L2T_H */
115