xref: /freebsd/sys/dev/cxgbe/t4_l2t.h (revision 724b4bfdf1306e4f2c451b6d146fe0fe0353b2c8)
1 /*-
2  * Copyright (c) 2011 Chelsio Communications, Inc.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  *
28  */
29 
30 #ifndef __T4_L2T_H
31 #define __T4_L2T_H
32 
33 /* identifies sync vs async L2T_WRITE_REQs */
34 #define S_SYNC_WR    12
35 #define V_SYNC_WR(x) ((x) << S_SYNC_WR)
36 #define F_SYNC_WR    V_SYNC_WR(1)
37 
38 enum { L2T_SIZE = 4096 };     /* # of L2T entries */
39 
40 enum {
41 	L2T_STATE_VALID,	/* entry is up to date */
42 	L2T_STATE_STALE,	/* entry may be used but needs revalidation */
43 	L2T_STATE_RESOLVING,	/* entry needs address resolution */
44 	L2T_STATE_FAILED,	/* failed to resolve */
45 	L2T_STATE_SYNC_WRITE,	/* synchronous write of entry underway */
46 
47 	/* when state is one of the below the entry is not hashed */
48 	L2T_STATE_SWITCHING,	/* entry is being used by a switching filter */
49 	L2T_STATE_UNUSED	/* entry not in use */
50 };
51 
52 /*
53  * Each L2T entry plays multiple roles.  First of all, it keeps state for the
54  * corresponding entry of the HW L2 table and maintains a queue of offload
55  * packets awaiting address resolution.  Second, it is a node of a hash table
56  * chain, where the nodes of the chain are linked together through their next
57  * pointer.  Finally, each node is a bucket of a hash table, pointing to the
58  * first element in its chain through its first pointer.
59  */
60 struct l2t_entry {
61 	uint16_t state;			/* entry state */
62 	uint16_t idx;			/* entry index */
63 	uint32_t addr;			/* next hop IP address */
64 	struct ifnet *ifp;		/* outgoing interface */
65 	uint16_t smt_idx;		/* SMT index */
66 	uint16_t vlan;			/* VLAN TCI (id: 0-11, prio: 13-15) */
67 	struct l2t_entry *first;	/* start of hash chain */
68 	struct l2t_entry *next;		/* next l2t_entry on chain */
69 	STAILQ_HEAD(, wrqe) wr_list;	/* list of WRs awaiting resolution */
70 	struct mtx lock;
71 	volatile int refcnt;		/* entry reference count */
72 	uint16_t hash;			/* hash bucket the entry is on */
73 	uint8_t lport;			/* associated offload logical port */
74 	uint8_t dmac[ETHER_ADDR_LEN];	/* next hop's MAC address */
75 };
76 
77 struct l2t_data {
78 	struct rwlock lock;
79 	volatile int nfree;	/* number of free entries */
80 	struct l2t_entry *rover;/* starting point for next allocation */
81 	struct l2t_entry l2tab[L2T_SIZE];
82 };
83 
84 
85 int t4_init_l2t(struct adapter *, int);
86 int t4_free_l2t(struct l2t_data *);
87 struct l2t_entry *t4_alloc_l2e(struct l2t_data *);
88 struct l2t_entry *t4_l2t_alloc_switching(struct l2t_data *);
89 int t4_l2t_set_switching(struct adapter *, struct l2t_entry *, uint16_t,
90     uint8_t, uint8_t *);
91 int t4_write_l2e(struct adapter *, struct l2t_entry *, int);
92 int do_l2t_write_rpl(struct sge_iq *, const struct rss_header *, struct mbuf *);
93 
94 static inline void
95 t4_l2t_release(struct l2t_entry *e)
96 {
97 	struct l2t_data *d = __containerof(e, struct l2t_data, l2tab[e->idx]);
98 
99 	if (atomic_fetchadd_int(&e->refcnt, -1) == 1)
100 		atomic_add_int(&d->nfree, 1);
101 }
102 
103 
104 #ifdef SBUF_DRAIN
105 int sysctl_l2t(SYSCTL_HANDLER_ARGS);
106 #endif
107 
108 #endif  /* __T4_L2T_H */
109