xref: /freebsd/sys/net/if_llatbl.h (revision 641a6cfb86023499caafe26a4d821a0b885cf00b)
1 /*
2  * Copyright (c) 2004 Luigi Rizzo, Alessandro Cerri. All rights reserved.
3  * Copyright (c) 2004-2008 Qing Li. All rights reserved.
4  * Copyright (c) 2008 Kip Macy. All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #ifndef	_NET_IF_LLATBL_H_
31 #define	_NET_IF_LLATBL_H_
32 
33 #include "opt_ofed.h"
34 
35 #include <sys/_rwlock.h>
36 #include <netinet/in.h>
37 
38 struct ifnet;
39 struct sysctl_req;
40 struct rt_msghdr;
41 struct rt_addrinfo;
42 
43 struct llentry;
44 LIST_HEAD(llentries, llentry);
45 
46 extern struct rwlock lltable_rwlock;
47 #define	LLTABLE_RLOCK()		rw_rlock(&lltable_rwlock)
48 #define	LLTABLE_RUNLOCK()	rw_runlock(&lltable_rwlock)
49 #define	LLTABLE_WLOCK()		rw_wlock(&lltable_rwlock)
50 #define	LLTABLE_WUNLOCK()	rw_wunlock(&lltable_rwlock)
51 #define	LLTABLE_LOCK_ASSERT()	rw_assert(&lltable_rwlock, RA_LOCKED)
52 
53 /*
54  * Code referencing llentry must at least hold
55  * a shared lock
56  */
57 struct llentry {
58 	LIST_ENTRY(llentry)	 lle_next;
59 	struct rwlock		 lle_lock;
60 	struct lltable		 *lle_tbl;
61 	struct llentries	 *lle_head;
62 	void			(*lle_free)(struct lltable *, struct llentry *);
63 	struct mbuf		 *la_hold;
64 	int     		 la_numheld;  /* # of packets currently held */
65 	time_t			 la_expire;
66 	uint16_t		 la_flags;
67 	uint16_t		 la_asked;
68 	uint16_t		 la_preempt;
69 	uint16_t		 ln_byhint;
70 	int16_t			 ln_state;	/* IPv6 has ND6_LLINFO_NOSTATE == -2 */
71 	uint16_t		 ln_router;
72 	time_t			 ln_ntick;
73 	int			 lle_refcnt;
74 
75 	union {
76 		uint64_t	mac_aligned;
77 		uint16_t	mac16[3];
78 #ifdef OFED
79 		uint8_t		mac8[20];	/* IB needs 20 bytes. */
80 #endif
81 	} ll_addr;
82 
83 	/* XXX af-private? */
84 	union {
85 		struct callout	ln_timer_ch;
86 		struct callout  la_timer;
87 	} lle_timer;
88 	/* NB: struct sockaddr must immediately follow */
89 };
90 
91 #define	LLE_WLOCK(lle)		rw_wlock(&(lle)->lle_lock)
92 #define	LLE_RLOCK(lle)		rw_rlock(&(lle)->lle_lock)
93 #define	LLE_WUNLOCK(lle)	rw_wunlock(&(lle)->lle_lock)
94 #define	LLE_RUNLOCK(lle)	rw_runlock(&(lle)->lle_lock)
95 #define	LLE_DOWNGRADE(lle)	rw_downgrade(&(lle)->lle_lock)
96 #define	LLE_TRY_UPGRADE(lle)	rw_try_upgrade(&(lle)->lle_lock)
97 #define	LLE_LOCK_INIT(lle)	rw_init_flags(&(lle)->lle_lock, "lle", RW_DUPOK)
98 #define	LLE_LOCK_DESTROY(lle)	rw_destroy(&(lle)->lle_lock)
99 #define	LLE_WLOCK_ASSERT(lle)	rw_assert(&(lle)->lle_lock, RA_WLOCKED)
100 
101 #define LLE_IS_VALID(lle)	(((lle) != NULL) && ((lle) != (void *)-1))
102 
103 #define	LLE_ADDREF(lle) do {					\
104 	LLE_WLOCK_ASSERT(lle);					\
105 	KASSERT((lle)->lle_refcnt >= 0,				\
106 		("negative refcnt %d", (lle)->lle_refcnt));	\
107 	(lle)->lle_refcnt++;					\
108 } while (0)
109 #define	LLE_REMREF(lle)	do {					\
110 	LLE_WLOCK_ASSERT(lle);					\
111 	KASSERT((lle)->lle_refcnt > 1,				\
112 		("bogus refcnt %d", (lle)->lle_refcnt));	\
113 	(lle)->lle_refcnt--;					\
114 } while (0)
115 
116 #define	LLE_FREE_LOCKED(lle) do {				\
117 	if ((lle)->lle_refcnt <= 1)				\
118 		(lle)->lle_free((lle)->lle_tbl, (lle));\
119 	else {							\
120 		(lle)->lle_refcnt--;				\
121 		LLE_WUNLOCK(lle);				\
122 	}							\
123 	/* guard against invalid refs */			\
124 	lle = NULL;						\
125 } while (0)
126 
127 #define	LLE_FREE(lle) do {					\
128 	LLE_WLOCK(lle);						\
129 	LLE_FREE_LOCKED(lle);					\
130 } while (0)
131 
132 
133 #define	ln_timer_ch	lle_timer.ln_timer_ch
134 #define	la_timer	lle_timer.la_timer
135 
136 /* XXX bad name */
137 #define	L3_ADDR(lle)	((struct sockaddr *)(&lle[1]))
138 #define	L3_ADDR_LEN(lle)	(((struct sockaddr *)(&lle[1]))->sa_len)
139 
140 #ifndef LLTBL_HASHTBL_SIZE
141 #define	LLTBL_HASHTBL_SIZE	32	/* default 32 ? */
142 #endif
143 
144 #ifndef LLTBL_HASHMASK
145 #define	LLTBL_HASHMASK	(LLTBL_HASHTBL_SIZE - 1)
146 #endif
147 
148 struct lltable {
149 	SLIST_ENTRY(lltable)	llt_link;
150 	struct llentries	lle_head[LLTBL_HASHTBL_SIZE];
151 	int			llt_af;
152 	struct ifnet		*llt_ifp;
153 
154 	void			(*llt_prefix_free)(struct lltable *,
155 				    const struct sockaddr *prefix,
156 				    const struct sockaddr *mask,
157 				    u_int flags);
158 	struct llentry *	(*llt_lookup)(struct lltable *, u_int flags,
159 				    const struct sockaddr *l3addr);
160 	int			(*llt_dump)(struct lltable *,
161 				     struct sysctl_req *);
162 };
163 MALLOC_DECLARE(M_LLTABLE);
164 
165 /*
166  * flags to be passed to arplookup.
167  */
168 #define	LLE_DELETED	0x0001	/* entry must be deleted */
169 #define	LLE_STATIC	0x0002	/* entry is static */
170 #define	LLE_IFADDR	0x0004	/* entry is interface addr */
171 #define	LLE_VALID	0x0008	/* ll_addr is valid */
172 #define	LLE_PROXY	0x0010	/* proxy entry ??? */
173 #define	LLE_PUB		0x0020	/* publish entry ??? */
174 #define	LLE_DELETE	0x4000	/* delete on a lookup - match LLE_IFADDR */
175 #define	LLE_CREATE	0x8000	/* create on a lookup miss */
176 #define	LLE_EXCLUSIVE	0x2000	/* return lle xlocked  */
177 
178 #define LLATBL_HASH(key, mask) \
179 	(((((((key >> 8) ^ key) >> 8) ^ key) >> 8) ^ key) & mask)
180 
181 struct lltable *lltable_init(struct ifnet *, int);
182 void		lltable_free(struct lltable *);
183 void		lltable_prefix_free(int, struct sockaddr *,
184                        struct sockaddr *, u_int);
185 #if 0
186 void		lltable_drain(int);
187 #endif
188 int		lltable_sysctl_dumparp(int, struct sysctl_req *);
189 
190 size_t		llentry_free(struct llentry *);
191 int		llentry_update(struct llentry **, struct lltable *,
192                        struct sockaddr_storage *, struct ifnet *);
193 
194 /*
195  * Generic link layer address lookup function.
196  */
197 static __inline struct llentry *
198 lla_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
199 {
200 	return llt->llt_lookup(llt, flags, l3addr);
201 }
202 
203 int		lla_rt_output(struct rt_msghdr *, struct rt_addrinfo *);
204 #endif  /* _NET_IF_LLATBL_H_ */
205