xref: /freebsd/sys/net/if_var.h (revision 9bd497b8354567454e075076d40c996e21bd6095)
1 /*-
2  * Copyright (c) 1982, 1986, 1989, 1993
3  *	The Regents of the University of California.  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  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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  *	From: @(#)if.h	8.1 (Berkeley) 6/10/93
30  * $FreeBSD$
31  */
32 
33 #ifndef	_NET_IF_VAR_H_
34 #define	_NET_IF_VAR_H_
35 
36 /*
37  * Structures defining a network interface, providing a packet
38  * transport mechanism (ala level 0 of the PUP protocols).
39  *
40  * Each interface accepts output datagrams of a specified maximum
41  * length, and provides higher level routines with input datagrams
42  * received from its medium.
43  *
44  * Output occurs when the routine if_output is called, with three parameters:
45  *	(*ifp->if_output)(ifp, m, dst, rt)
46  * Here m is the mbuf chain to be sent and dst is the destination address.
47  * The output routine encapsulates the supplied datagram if necessary,
48  * and then transmits it on its medium.
49  *
50  * On input, each interface unwraps the data received by it, and either
51  * places it on the input queue of an internetwork datagram routine
52  * and posts the associated software interrupt, or passes the datagram to a raw
53  * packet input routine.
54  *
55  * Routines exist for locating interfaces by their addresses
56  * or for locating an interface on a certain network, as well as more general
57  * routing and gateway routines maintaining information used to locate
58  * interfaces.  These routines live in the files if.c and route.c
59  */
60 
61 #ifdef __STDC__
62 /*
63  * Forward structure declarations for function prototypes [sic].
64  */
65 struct	mbuf;
66 struct	thread;
67 struct	rtentry;
68 struct	rt_addrinfo;
69 struct	socket;
70 struct	ether_header;
71 struct	carp_if;
72 struct  ifvlantrunk;
73 struct	route;
74 struct	vnet;
75 #endif
76 
77 #include <sys/queue.h>		/* get TAILQ macros */
78 
79 #ifdef _KERNEL
80 #include <sys/mbuf.h>
81 #include <sys/eventhandler.h>
82 #include <sys/buf_ring.h>
83 #include <net/vnet.h>
84 #endif /* _KERNEL */
85 #include <sys/lock.h>		/* XXX */
86 #include <sys/mutex.h>		/* XXX */
87 #include <sys/rwlock.h>		/* XXX */
88 #include <sys/sx.h>		/* XXX */
89 #include <sys/event.h>		/* XXX */
90 #include <sys/_task.h>
91 
92 #define	IF_DUNIT_NONE	-1
93 
94 #include <altq/if_altq.h>
95 
96 TAILQ_HEAD(ifnethead, ifnet);	/* we use TAILQs so that the order of */
97 TAILQ_HEAD(ifaddrhead, ifaddr);	/* instantiation is preserved in the list */
98 TAILQ_HEAD(ifprefixhead, ifprefix);
99 TAILQ_HEAD(ifmultihead, ifmultiaddr);
100 TAILQ_HEAD(ifgrouphead, ifg_group);
101 
102 /*
103  * Structure defining a queue for a network interface.
104  */
105 struct	ifqueue {
106 	struct	mbuf *ifq_head;
107 	struct	mbuf *ifq_tail;
108 	int	ifq_len;
109 	int	ifq_maxlen;
110 	int	ifq_drops;
111 	struct	mtx ifq_mtx;
112 };
113 
114 /*
115  * Structure defining a network interface.
116  *
117  * (Would like to call this struct ``if'', but C isn't PL/1.)
118  */
119 
120 struct ifnet {
121 	void	*if_softc;		/* pointer to driver state */
122 	void	*if_l2com;		/* pointer to protocol bits */
123 	struct vnet *if_vnet;		/* pointer to network stack instance */
124 	TAILQ_ENTRY(ifnet) if_link; 	/* all struct ifnets are chained */
125 	char	if_xname[IFNAMSIZ];	/* external name (name + unit) */
126 	const char *if_dname;		/* driver name */
127 	int	if_dunit;		/* unit or IF_DUNIT_NONE */
128 	u_int	if_refcount;		/* reference count */
129 	struct	ifaddrhead if_addrhead;	/* linked list of addresses per if */
130 		/*
131 		 * if_addrhead is the list of all addresses associated to
132 		 * an interface.
133 		 * Some code in the kernel assumes that first element
134 		 * of the list has type AF_LINK, and contains sockaddr_dl
135 		 * addresses which store the link-level address and the name
136 		 * of the interface.
137 		 * However, access to the AF_LINK address through this
138 		 * field is deprecated. Use if_addr or ifaddr_byindex() instead.
139 		 */
140 	int	if_pcount;		/* number of promiscuous listeners */
141 	struct	carp_if *if_carp;	/* carp interface structure */
142 	struct	bpf_if *if_bpf;		/* packet filter structure */
143 	u_short	if_index;		/* numeric abbreviation for this if  */
144 	short	if_index_reserved;	/* spare space to grow if_index */
145 	struct  ifvlantrunk *if_vlantrunk; /* pointer to 802.1q data */
146 	int	if_flags;		/* up/down, broadcast, etc. */
147 	int	if_capabilities;	/* interface features & capabilities */
148 	int	if_capenable;		/* enabled features & capabilities */
149 	void	*if_linkmib;		/* link-type-specific MIB data */
150 	size_t	if_linkmiblen;		/* length of above data */
151 	struct	if_data if_data;
152 	struct	ifmultihead if_multiaddrs; /* multicast addresses configured */
153 	int	if_amcount;		/* number of all-multicast requests */
154 /* procedure handles */
155 	int	(*if_output)		/* output routine (enqueue) */
156 		(struct ifnet *, struct mbuf *, struct sockaddr *,
157 		     struct route *);
158 	void	(*if_input)		/* input routine (from h/w driver) */
159 		(struct ifnet *, struct mbuf *);
160 	void	(*if_start)		/* initiate output routine */
161 		(struct ifnet *);
162 	int	(*if_ioctl)		/* ioctl routine */
163 		(struct ifnet *, u_long, caddr_t);
164 	void	(*if_init)		/* Init routine */
165 		(void *);
166 	int	(*if_resolvemulti)	/* validate/resolve multicast */
167 		(struct ifnet *, struct sockaddr **, struct sockaddr *);
168 	void	(*if_qflush)		/* flush any queues */
169 		(struct ifnet *);
170 	int	(*if_transmit)		/* initiate output routine */
171 		(struct ifnet *, struct mbuf *);
172 	void	(*if_reassign)		/* reassign to vnet routine */
173 		(struct ifnet *, struct vnet *, char *);
174 	struct	vnet *if_home_vnet;	/* where this ifnet originates from */
175 	struct	ifaddr	*if_addr;	/* pointer to link-level address */
176 	void	*if_llsoftc;		/* link layer softc */
177 	int	if_drv_flags;		/* driver-managed status flags */
178 	struct  ifaltq if_snd;		/* output queue (includes altq) */
179 	const u_int8_t *if_broadcastaddr; /* linklevel broadcast bytestring */
180 
181 	void	*if_bridge;		/* bridge glue */
182 
183 	struct	label *if_label;	/* interface MAC label */
184 
185 	/* these are only used by IPv6 */
186 	struct	ifprefixhead if_prefixhead; /* list of prefixes per if */
187 	void	*if_afdata[AF_MAX];
188 	int	if_afdata_initialized;
189 	struct	rwlock if_afdata_lock;
190 	struct	task if_linktask;	/* task for link change events */
191 	struct	mtx if_addr_mtx;	/* mutex to protect address lists */
192 
193 	LIST_ENTRY(ifnet) if_clones;	/* interfaces of a cloner */
194 	TAILQ_HEAD(, ifg_list) if_groups; /* linked list of groups per if */
195 					/* protected by if_addr_mtx */
196 	void	*if_pf_kif;
197 	void	*if_lagg;		/* lagg glue */
198 	u_char	 if_alloctype;		/* if_type at time of allocation */
199 
200 	/*
201 	 * Spare fields are added so that we can modify sensitive data
202 	 * structures without changing the kernel binary interface, and must
203 	 * be used with care where binary compatibility is required.
204 	 */
205 	char	 if_cspare[3];
206 	void	*if_pspare[8];
207 	int	if_ispare[4];
208 };
209 
210 typedef void if_init_f_t(void *);
211 
212 /*
213  * XXX These aliases are terribly dangerous because they could apply
214  * to anything.
215  */
216 #define	if_mtu		if_data.ifi_mtu
217 #define	if_type		if_data.ifi_type
218 #define if_physical	if_data.ifi_physical
219 #define	if_addrlen	if_data.ifi_addrlen
220 #define	if_hdrlen	if_data.ifi_hdrlen
221 #define	if_metric	if_data.ifi_metric
222 #define	if_link_state	if_data.ifi_link_state
223 #define	if_baudrate	if_data.ifi_baudrate
224 #define	if_hwassist	if_data.ifi_hwassist
225 #define	if_ipackets	if_data.ifi_ipackets
226 #define	if_ierrors	if_data.ifi_ierrors
227 #define	if_opackets	if_data.ifi_opackets
228 #define	if_oerrors	if_data.ifi_oerrors
229 #define	if_collisions	if_data.ifi_collisions
230 #define	if_ibytes	if_data.ifi_ibytes
231 #define	if_obytes	if_data.ifi_obytes
232 #define	if_imcasts	if_data.ifi_imcasts
233 #define	if_omcasts	if_data.ifi_omcasts
234 #define	if_iqdrops	if_data.ifi_iqdrops
235 #define	if_noproto	if_data.ifi_noproto
236 #define	if_lastchange	if_data.ifi_lastchange
237 
238 /* for compatibility with other BSDs */
239 #define	if_addrlist	if_addrhead
240 #define	if_list		if_link
241 #define	if_name(ifp)	((ifp)->if_xname)
242 
243 /*
244  * Locks for address lists on the network interface.
245  */
246 #define	IF_ADDR_LOCK_INIT(if)	mtx_init(&(if)->if_addr_mtx,		\
247 				    "if_addr_mtx", NULL, MTX_DEF)
248 #define	IF_ADDR_LOCK_DESTROY(if)	mtx_destroy(&(if)->if_addr_mtx)
249 #define	IF_ADDR_LOCK(if)	mtx_lock(&(if)->if_addr_mtx)
250 #define	IF_ADDR_UNLOCK(if)	mtx_unlock(&(if)->if_addr_mtx)
251 #define	IF_ADDR_LOCK_ASSERT(if)	mtx_assert(&(if)->if_addr_mtx, MA_OWNED)
252 
253 /*
254  * Function variations on locking macros intended to be used by loadable
255  * kernel modules in order to divorce them from the internals of address list
256  * locking.
257  */
258 void	if_addr_rlock(struct ifnet *ifp);	/* if_addrhead */
259 void	if_addr_runlock(struct ifnet *ifp);	/* if_addrhead */
260 void	if_maddr_rlock(struct ifnet *ifp);	/* if_multiaddrs */
261 void	if_maddr_runlock(struct ifnet *ifp);	/* if_multiaddrs */
262 
263 /*
264  * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
265  * are queues of messages stored on ifqueue structures
266  * (defined above).  Entries are added to and deleted from these structures
267  * by these macros, which should be called with ipl raised to splimp().
268  */
269 #define IF_LOCK(ifq)		mtx_lock(&(ifq)->ifq_mtx)
270 #define IF_UNLOCK(ifq)		mtx_unlock(&(ifq)->ifq_mtx)
271 #define	IF_LOCK_ASSERT(ifq)	mtx_assert(&(ifq)->ifq_mtx, MA_OWNED)
272 #define	_IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
273 #define	_IF_DROP(ifq)		((ifq)->ifq_drops++)
274 #define	_IF_QLEN(ifq)		((ifq)->ifq_len)
275 
276 #define	_IF_ENQUEUE(ifq, m) do { 				\
277 	(m)->m_nextpkt = NULL;					\
278 	if ((ifq)->ifq_tail == NULL) 				\
279 		(ifq)->ifq_head = m; 				\
280 	else 							\
281 		(ifq)->ifq_tail->m_nextpkt = m; 		\
282 	(ifq)->ifq_tail = m; 					\
283 	(ifq)->ifq_len++; 					\
284 } while (0)
285 
286 #define IF_ENQUEUE(ifq, m) do {					\
287 	IF_LOCK(ifq); 						\
288 	_IF_ENQUEUE(ifq, m); 					\
289 	IF_UNLOCK(ifq); 					\
290 } while (0)
291 
292 #define	_IF_PREPEND(ifq, m) do {				\
293 	(m)->m_nextpkt = (ifq)->ifq_head; 			\
294 	if ((ifq)->ifq_tail == NULL) 				\
295 		(ifq)->ifq_tail = (m); 				\
296 	(ifq)->ifq_head = (m); 					\
297 	(ifq)->ifq_len++; 					\
298 } while (0)
299 
300 #define IF_PREPEND(ifq, m) do {		 			\
301 	IF_LOCK(ifq); 						\
302 	_IF_PREPEND(ifq, m); 					\
303 	IF_UNLOCK(ifq); 					\
304 } while (0)
305 
306 #define	_IF_DEQUEUE(ifq, m) do { 				\
307 	(m) = (ifq)->ifq_head; 					\
308 	if (m) { 						\
309 		if (((ifq)->ifq_head = (m)->m_nextpkt) == NULL)	\
310 			(ifq)->ifq_tail = NULL; 		\
311 		(m)->m_nextpkt = NULL; 				\
312 		(ifq)->ifq_len--; 				\
313 	} 							\
314 } while (0)
315 
316 #define IF_DEQUEUE(ifq, m) do { 				\
317 	IF_LOCK(ifq); 						\
318 	_IF_DEQUEUE(ifq, m); 					\
319 	IF_UNLOCK(ifq); 					\
320 } while (0)
321 
322 #define	_IF_POLL(ifq, m)	((m) = (ifq)->ifq_head)
323 #define	IF_POLL(ifq, m)		_IF_POLL(ifq, m)
324 
325 #define _IF_DRAIN(ifq) do { 					\
326 	struct mbuf *m; 					\
327 	for (;;) { 						\
328 		_IF_DEQUEUE(ifq, m); 				\
329 		if (m == NULL) 					\
330 			break; 					\
331 		m_freem(m); 					\
332 	} 							\
333 } while (0)
334 
335 #define IF_DRAIN(ifq) do {					\
336 	IF_LOCK(ifq);						\
337 	_IF_DRAIN(ifq);						\
338 	IF_UNLOCK(ifq);						\
339 } while(0)
340 
341 #ifdef _KERNEL
342 /* interface link layer address change event */
343 typedef void (*iflladdr_event_handler_t)(void *, struct ifnet *);
344 EVENTHANDLER_DECLARE(iflladdr_event, iflladdr_event_handler_t);
345 /* interface address change event */
346 typedef void (*ifaddr_event_handler_t)(void *, struct ifnet *);
347 EVENTHANDLER_DECLARE(ifaddr_event, ifaddr_event_handler_t);
348 /* new interface arrival event */
349 typedef void (*ifnet_arrival_event_handler_t)(void *, struct ifnet *);
350 EVENTHANDLER_DECLARE(ifnet_arrival_event, ifnet_arrival_event_handler_t);
351 /* interface departure event */
352 typedef void (*ifnet_departure_event_handler_t)(void *, struct ifnet *);
353 EVENTHANDLER_DECLARE(ifnet_departure_event, ifnet_departure_event_handler_t);
354 
355 /*
356  * interface groups
357  */
358 struct ifg_group {
359 	char				 ifg_group[IFNAMSIZ];
360 	u_int				 ifg_refcnt;
361 	void				*ifg_pf_kif;
362 	TAILQ_HEAD(, ifg_member)	 ifg_members;
363 	TAILQ_ENTRY(ifg_group)		 ifg_next;
364 };
365 
366 struct ifg_member {
367 	TAILQ_ENTRY(ifg_member)	 ifgm_next;
368 	struct ifnet		*ifgm_ifp;
369 };
370 
371 struct ifg_list {
372 	struct ifg_group	*ifgl_group;
373 	TAILQ_ENTRY(ifg_list)	 ifgl_next;
374 };
375 
376 /* group attach event */
377 typedef void (*group_attach_event_handler_t)(void *, struct ifg_group *);
378 EVENTHANDLER_DECLARE(group_attach_event, group_attach_event_handler_t);
379 /* group detach event */
380 typedef void (*group_detach_event_handler_t)(void *, struct ifg_group *);
381 EVENTHANDLER_DECLARE(group_detach_event, group_detach_event_handler_t);
382 /* group change event */
383 typedef void (*group_change_event_handler_t)(void *, const char *);
384 EVENTHANDLER_DECLARE(group_change_event, group_change_event_handler_t);
385 
386 #define	IF_AFDATA_LOCK_INIT(ifp)	\
387 	rw_init(&(ifp)->if_afdata_lock, "if_afdata")
388 
389 #define	IF_AFDATA_WLOCK(ifp)	rw_wlock(&(ifp)->if_afdata_lock)
390 #define	IF_AFDATA_RLOCK(ifp)	rw_rlock(&(ifp)->if_afdata_lock)
391 #define	IF_AFDATA_WUNLOCK(ifp)	rw_wunlock(&(ifp)->if_afdata_lock)
392 #define	IF_AFDATA_RUNLOCK(ifp)	rw_runlock(&(ifp)->if_afdata_lock)
393 #define	IF_AFDATA_LOCK(ifp)	IF_AFDATA_WLOCK(ifp)
394 #define	IF_AFDATA_UNLOCK(ifp)	IF_AFDATA_WUNLOCK(ifp)
395 #define	IF_AFDATA_TRYLOCK(ifp)	rw_try_wlock(&(ifp)->if_afdata_lock)
396 #define	IF_AFDATA_DESTROY(ifp)	rw_destroy(&(ifp)->if_afdata_lock)
397 
398 #define	IF_AFDATA_LOCK_ASSERT(ifp)	rw_assert(&(ifp)->if_afdata_lock, RA_LOCKED)
399 #define	IF_AFDATA_UNLOCK_ASSERT(ifp)	rw_assert(&(ifp)->if_afdata_lock, RA_UNLOCKED)
400 
401 int	if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp,
402 	    int adjust);
403 #define	IF_HANDOFF(ifq, m, ifp)			\
404 	if_handoff((struct ifqueue *)ifq, m, ifp, 0)
405 #define	IF_HANDOFF_ADJ(ifq, m, ifp, adj)	\
406 	if_handoff((struct ifqueue *)ifq, m, ifp, adj)
407 
408 void	if_start(struct ifnet *);
409 
410 #define	IFQ_ENQUEUE(ifq, m, err)					\
411 do {									\
412 	IF_LOCK(ifq);							\
413 	if (ALTQ_IS_ENABLED(ifq))					\
414 		ALTQ_ENQUEUE(ifq, m, NULL, err);			\
415 	else {								\
416 		if (_IF_QFULL(ifq)) {					\
417 			m_freem(m);					\
418 			(err) = ENOBUFS;				\
419 		} else {						\
420 			_IF_ENQUEUE(ifq, m);				\
421 			(err) = 0;					\
422 		}							\
423 	}								\
424 	if (err)							\
425 		(ifq)->ifq_drops++;					\
426 	IF_UNLOCK(ifq);							\
427 } while (0)
428 
429 #define	IFQ_DEQUEUE_NOLOCK(ifq, m)					\
430 do {									\
431 	if (TBR_IS_ENABLED(ifq))					\
432 		(m) = tbr_dequeue_ptr(ifq, ALTDQ_REMOVE);		\
433 	else if (ALTQ_IS_ENABLED(ifq))					\
434 		ALTQ_DEQUEUE(ifq, m);					\
435 	else								\
436 		_IF_DEQUEUE(ifq, m);					\
437 } while (0)
438 
439 #define	IFQ_DEQUEUE(ifq, m)						\
440 do {									\
441 	IF_LOCK(ifq);							\
442 	IFQ_DEQUEUE_NOLOCK(ifq, m);					\
443 	IF_UNLOCK(ifq);							\
444 } while (0)
445 
446 #define	IFQ_POLL_NOLOCK(ifq, m)						\
447 do {									\
448 	if (TBR_IS_ENABLED(ifq))					\
449 		(m) = tbr_dequeue_ptr(ifq, ALTDQ_POLL);			\
450 	else if (ALTQ_IS_ENABLED(ifq))					\
451 		ALTQ_POLL(ifq, m);					\
452 	else								\
453 		_IF_POLL(ifq, m);					\
454 } while (0)
455 
456 #define	IFQ_POLL(ifq, m)						\
457 do {									\
458 	IF_LOCK(ifq);							\
459 	IFQ_POLL_NOLOCK(ifq, m);					\
460 	IF_UNLOCK(ifq);							\
461 } while (0)
462 
463 #define	IFQ_PURGE_NOLOCK(ifq)						\
464 do {									\
465 	if (ALTQ_IS_ENABLED(ifq)) {					\
466 		ALTQ_PURGE(ifq);					\
467 	} else								\
468 		_IF_DRAIN(ifq);						\
469 } while (0)
470 
471 #define	IFQ_PURGE(ifq)							\
472 do {									\
473 	IF_LOCK(ifq);							\
474 	IFQ_PURGE_NOLOCK(ifq);						\
475 	IF_UNLOCK(ifq);							\
476 } while (0)
477 
478 #define	IFQ_SET_READY(ifq)						\
479 	do { ((ifq)->altq_flags |= ALTQF_READY); } while (0)
480 
481 #define	IFQ_LOCK(ifq)			IF_LOCK(ifq)
482 #define	IFQ_UNLOCK(ifq)			IF_UNLOCK(ifq)
483 #define	IFQ_LOCK_ASSERT(ifq)		IF_LOCK_ASSERT(ifq)
484 #define	IFQ_IS_EMPTY(ifq)		((ifq)->ifq_len == 0)
485 #define	IFQ_INC_LEN(ifq)		((ifq)->ifq_len++)
486 #define	IFQ_DEC_LEN(ifq)		(--(ifq)->ifq_len)
487 #define	IFQ_INC_DROPS(ifq)		((ifq)->ifq_drops++)
488 #define	IFQ_SET_MAXLEN(ifq, len)	((ifq)->ifq_maxlen = (len))
489 
490 /*
491  * The IFF_DRV_OACTIVE test should really occur in the device driver, not in
492  * the handoff logic, as that flag is locked by the device driver.
493  */
494 #define	IFQ_HANDOFF_ADJ(ifp, m, adj, err)				\
495 do {									\
496 	int len;							\
497 	short mflags;							\
498 									\
499 	len = (m)->m_pkthdr.len;					\
500 	mflags = (m)->m_flags;						\
501 	IFQ_ENQUEUE(&(ifp)->if_snd, m, err);				\
502 	if ((err) == 0) {						\
503 		(ifp)->if_obytes += len + (adj);			\
504 		if (mflags & M_MCAST)					\
505 			(ifp)->if_omcasts++;				\
506 		if (((ifp)->if_drv_flags & IFF_DRV_OACTIVE) == 0)	\
507 			if_start(ifp);					\
508 	}								\
509 } while (0)
510 
511 #define	IFQ_HANDOFF(ifp, m, err)					\
512 	IFQ_HANDOFF_ADJ(ifp, m, 0, err)
513 
514 #define	IFQ_DRV_DEQUEUE(ifq, m)						\
515 do {									\
516 	(m) = (ifq)->ifq_drv_head;					\
517 	if (m) {							\
518 		if (((ifq)->ifq_drv_head = (m)->m_nextpkt) == NULL)	\
519 			(ifq)->ifq_drv_tail = NULL;			\
520 		(m)->m_nextpkt = NULL;					\
521 		(ifq)->ifq_drv_len--;					\
522 	} else {							\
523 		IFQ_LOCK(ifq);						\
524 		IFQ_DEQUEUE_NOLOCK(ifq, m);				\
525 		while ((ifq)->ifq_drv_len < (ifq)->ifq_drv_maxlen) {	\
526 			struct mbuf *m0;				\
527 			IFQ_DEQUEUE_NOLOCK(ifq, m0);			\
528 			if (m0 == NULL)					\
529 				break;					\
530 			m0->m_nextpkt = NULL;				\
531 			if ((ifq)->ifq_drv_tail == NULL)		\
532 				(ifq)->ifq_drv_head = m0;		\
533 			else						\
534 				(ifq)->ifq_drv_tail->m_nextpkt = m0;	\
535 			(ifq)->ifq_drv_tail = m0;			\
536 			(ifq)->ifq_drv_len++;				\
537 		}							\
538 		IFQ_UNLOCK(ifq);					\
539 	}								\
540 } while (0)
541 
542 #define	IFQ_DRV_PREPEND(ifq, m)						\
543 do {									\
544 	(m)->m_nextpkt = (ifq)->ifq_drv_head;				\
545 	if ((ifq)->ifq_drv_tail == NULL)				\
546 		(ifq)->ifq_drv_tail = (m);				\
547 	(ifq)->ifq_drv_head = (m);					\
548 	(ifq)->ifq_drv_len++;						\
549 } while (0)
550 
551 #define	IFQ_DRV_IS_EMPTY(ifq)						\
552 	(((ifq)->ifq_drv_len == 0) && ((ifq)->ifq_len == 0))
553 
554 #define	IFQ_DRV_PURGE(ifq)						\
555 do {									\
556 	struct mbuf *m, *n = (ifq)->ifq_drv_head;			\
557 	while((m = n) != NULL) {					\
558 		n = m->m_nextpkt;					\
559 		m_freem(m);						\
560 	}								\
561 	(ifq)->ifq_drv_head = (ifq)->ifq_drv_tail = NULL;		\
562 	(ifq)->ifq_drv_len = 0;						\
563 	IFQ_PURGE(ifq);							\
564 } while (0)
565 
566 #ifdef _KERNEL
567 static __inline void
568 drbr_stats_update(struct ifnet *ifp, int len, int mflags)
569 {
570 #ifndef NO_SLOW_STATS
571 	ifp->if_obytes += len;
572 	if (mflags & M_MCAST)
573 		ifp->if_omcasts++;
574 #endif
575 }
576 
577 static __inline int
578 drbr_enqueue(struct ifnet *ifp, struct buf_ring *br, struct mbuf *m)
579 {
580 	int error = 0;
581 	int len = m->m_pkthdr.len;
582 	int mflags = m->m_flags;
583 
584 #ifdef ALTQ
585 	if (ALTQ_IS_ENABLED(&ifp->if_snd)) {
586 		IFQ_ENQUEUE(&ifp->if_snd, m, error);
587 		return (error);
588 	}
589 #endif
590 	if ((error = buf_ring_enqueue_bytes(br, m, len)) == ENOBUFS) {
591 		br->br_drops++;
592 		m_freem(m);
593 	} else
594 		drbr_stats_update(ifp, len, mflags);
595 
596 	return (error);
597 }
598 
599 static __inline void
600 drbr_flush(struct ifnet *ifp, struct buf_ring *br)
601 {
602 	struct mbuf *m;
603 
604 #ifdef ALTQ
605 	if (ifp != NULL && ALTQ_IS_ENABLED(&ifp->if_snd)) {
606 		while (!IFQ_IS_EMPTY(&ifp->if_snd)) {
607 			IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
608 			m_freem(m);
609 		}
610 	}
611 #endif
612 	while ((m = buf_ring_dequeue_sc(br)) != NULL)
613 		m_freem(m);
614 }
615 
616 static __inline void
617 drbr_free(struct buf_ring *br, struct malloc_type *type)
618 {
619 
620 	drbr_flush(NULL, br);
621 	buf_ring_free(br, type);
622 }
623 
624 static __inline struct mbuf *
625 drbr_dequeue(struct ifnet *ifp, struct buf_ring *br)
626 {
627 #ifdef ALTQ
628 	struct mbuf *m;
629 
630 	if (ALTQ_IS_ENABLED(&ifp->if_snd)) {
631 		IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
632 		return (m);
633 	}
634 #endif
635 	return (buf_ring_dequeue_sc(br));
636 }
637 
638 static __inline struct mbuf *
639 drbr_dequeue_cond(struct ifnet *ifp, struct buf_ring *br,
640     int (*func) (struct mbuf *, void *), void *arg)
641 {
642 	struct mbuf *m;
643 #ifdef ALTQ
644 	/*
645 	 * XXX need to evaluate / requeue
646 	 */
647 	if (ALTQ_IS_ENABLED(&ifp->if_snd)) {
648 		IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
649 		return (m);
650 	}
651 #endif
652 	m = buf_ring_peek(br);
653 	if (m == NULL || func(m, arg) == 0)
654 		return (NULL);
655 
656 	return (buf_ring_dequeue_sc(br));
657 }
658 
659 static __inline int
660 drbr_empty(struct ifnet *ifp, struct buf_ring *br)
661 {
662 #ifdef ALTQ
663 	if (ALTQ_IS_ENABLED(&ifp->if_snd))
664 		return (IFQ_DRV_IS_EMPTY(&ifp->if_snd));
665 #endif
666 	return (buf_ring_empty(br));
667 }
668 
669 static __inline int
670 drbr_inuse(struct ifnet *ifp, struct buf_ring *br)
671 {
672 #ifdef ALTQ
673 	if (ALTQ_IS_ENABLED(&ifp->if_snd))
674 		return (ifp->if_snd.ifq_len);
675 #endif
676 	return (buf_ring_count(br));
677 }
678 #endif
679 /*
680  * 72 was chosen below because it is the size of a TCP/IP
681  * header (40) + the minimum mss (32).
682  */
683 #define	IF_MINMTU	72
684 #define	IF_MAXMTU	65535
685 
686 #endif /* _KERNEL */
687 
688 /*
689  * The ifaddr structure contains information about one address
690  * of an interface.  They are maintained by the different address families,
691  * are allocated and attached when an address is set, and are linked
692  * together so all addresses for an interface can be located.
693  *
694  * NOTE: a 'struct ifaddr' is always at the beginning of a larger
695  * chunk of malloc'ed memory, where we store the three addresses
696  * (ifa_addr, ifa_dstaddr and ifa_netmask) referenced here.
697  */
698 struct ifaddr {
699 	struct	sockaddr *ifa_addr;	/* address of interface */
700 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
701 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
702 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
703 	struct	if_data if_data;	/* not all members are meaningful */
704 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
705 	TAILQ_ENTRY(ifaddr) ifa_link;	/* queue macro glue */
706 	void	(*ifa_rtrequest)	/* check or clean routes (+ or -)'d */
707 		(int, struct rtentry *, struct rt_addrinfo *);
708 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
709 	u_int	ifa_refcnt;		/* references to this structure */
710 	int	ifa_metric;		/* cost of going out this interface */
711 	int (*ifa_claim_addr)		/* check if an addr goes to this if */
712 		(struct ifaddr *, struct sockaddr *);
713 	struct mtx ifa_mtx;
714 };
715 #define	IFA_ROUTE	RTF_UP		/* route installed */
716 #define IFA_RTSELF	RTF_HOST	/* loopback route to self installed */
717 
718 /* for compatibility with other BSDs */
719 #define	ifa_list	ifa_link
720 
721 #ifdef _KERNEL
722 #define	IFA_LOCK(ifa)		mtx_lock(&(ifa)->ifa_mtx)
723 #define	IFA_UNLOCK(ifa)		mtx_unlock(&(ifa)->ifa_mtx)
724 
725 void	ifa_free(struct ifaddr *ifa);
726 void	ifa_init(struct ifaddr *ifa);
727 void	ifa_ref(struct ifaddr *ifa);
728 #endif
729 
730 /*
731  * The prefix structure contains information about one prefix
732  * of an interface.  They are maintained by the different address families,
733  * are allocated and attached when a prefix or an address is set,
734  * and are linked together so all prefixes for an interface can be located.
735  */
736 struct ifprefix {
737 	struct	sockaddr *ifpr_prefix;	/* prefix of interface */
738 	struct	ifnet *ifpr_ifp;	/* back-pointer to interface */
739 	TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
740 	u_char	ifpr_plen;		/* prefix length in bits */
741 	u_char	ifpr_type;		/* protocol dependent prefix type */
742 };
743 
744 /*
745  * Multicast address structure.  This is analogous to the ifaddr
746  * structure except that it keeps track of multicast addresses.
747  */
748 struct ifmultiaddr {
749 	TAILQ_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
750 	struct	sockaddr *ifma_addr; 	/* address this membership is for */
751 	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
752 	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
753 	u_int	ifma_refcount;		/* reference count */
754 	void	*ifma_protospec;	/* protocol-specific state, if any */
755 	struct	ifmultiaddr *ifma_llifma; /* pointer to ifma for ifma_lladdr */
756 };
757 
758 #ifdef _KERNEL
759 
760 extern	struct rwlock ifnet_rwlock;
761 extern	struct sx ifnet_sxlock;
762 
763 #define	IFNET_LOCK_INIT() do {						\
764 	rw_init_flags(&ifnet_rwlock, "ifnet_rw",  RW_RECURSE);		\
765 	sx_init_flags(&ifnet_sxlock, "ifnet_sx",  SX_RECURSE);		\
766 } while(0)
767 
768 #define	IFNET_WLOCK() do {						\
769 	sx_xlock(&ifnet_sxlock);					\
770 	rw_wlock(&ifnet_rwlock);					\
771 } while (0)
772 
773 #define	IFNET_WUNLOCK() do {						\
774 	rw_wunlock(&ifnet_rwlock);					\
775 	sx_xunlock(&ifnet_sxlock);					\
776 } while (0)
777 
778 /*
779  * To assert the ifnet lock, you must know not only whether it's for read or
780  * write, but also whether it was acquired with sleep support or not.
781  */
782 #define	IFNET_RLOCK_ASSERT()		sx_assert(&ifnet_sxlock, SA_SLOCKED)
783 #define	IFNET_RLOCK_NOSLEEP_ASSERT()	rw_assert(&ifnet_rwlock, RA_RLOCKED)
784 #define	IFNET_WLOCK_ASSERT() do {					\
785 	sx_assert(&ifnet_sxlock, SA_XLOCKED);				\
786 	rw_assert(&ifnet_rwlock, RA_WLOCKED);				\
787 } while (0)
788 
789 #define	IFNET_RLOCK()		sx_slock(&ifnet_sxlock)
790 #define	IFNET_RLOCK_NOSLEEP()	rw_rlock(&ifnet_rwlock)
791 #define	IFNET_RUNLOCK()		sx_sunlock(&ifnet_sxlock)
792 #define	IFNET_RUNLOCK_NOSLEEP()	rw_runlock(&ifnet_rwlock)
793 
794 /*
795  * Look up an ifnet given its index; the _ref variant also acquires a
796  * reference that must be freed using if_rele().  It is almost always a bug
797  * to call ifnet_byindex() instead if ifnet_byindex_ref().
798  */
799 struct ifnet	*ifnet_byindex(u_short idx);
800 struct ifnet	*ifnet_byindex_locked(u_short idx);
801 struct ifnet	*ifnet_byindex_ref(u_short idx);
802 
803 /*
804  * Given the index, ifaddr_byindex() returns the one and only
805  * link-level ifaddr for the interface. You are not supposed to use
806  * it to traverse the list of addresses associated to the interface.
807  */
808 struct ifaddr	*ifaddr_byindex(u_short idx);
809 
810 VNET_DECLARE(struct ifnethead, ifnet);
811 VNET_DECLARE(struct ifgrouphead, ifg_head);
812 VNET_DECLARE(int, if_index);
813 VNET_DECLARE(struct ifnet *, loif);	/* first loopback interface */
814 VNET_DECLARE(int, useloopback);
815 
816 #define	V_ifnet		VNET(ifnet)
817 #define	V_ifg_head	VNET(ifg_head)
818 #define	V_if_index	VNET(if_index)
819 #define	V_loif		VNET(loif)
820 #define	V_useloopback	VNET(useloopback)
821 
822 extern	int ifqmaxlen;
823 
824 int	if_addgroup(struct ifnet *, const char *);
825 int	if_delgroup(struct ifnet *, const char *);
826 int	if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
827 int	if_allmulti(struct ifnet *, int);
828 struct	ifnet* if_alloc(u_char);
829 void	if_attach(struct ifnet *);
830 void	if_dead(struct ifnet *);
831 int	if_delmulti(struct ifnet *, struct sockaddr *);
832 void	if_delmulti_ifma(struct ifmultiaddr *);
833 void	if_detach(struct ifnet *);
834 void	if_vmove(struct ifnet *, struct vnet *);
835 void	if_purgeaddrs(struct ifnet *);
836 void	if_delallmulti(struct ifnet *);
837 void	if_down(struct ifnet *);
838 struct ifmultiaddr *
839 	if_findmulti(struct ifnet *, struct sockaddr *);
840 void	if_free(struct ifnet *);
841 void	if_free_type(struct ifnet *, u_char);
842 void	if_initname(struct ifnet *, const char *, int);
843 void	if_link_state_change(struct ifnet *, int);
844 int	if_printf(struct ifnet *, const char *, ...) __printflike(2, 3);
845 void	if_qflush(struct ifnet *);
846 void	if_ref(struct ifnet *);
847 void	if_rele(struct ifnet *);
848 int	if_setlladdr(struct ifnet *, const u_char *, int);
849 void	if_up(struct ifnet *);
850 int	ifioctl(struct socket *, u_long, caddr_t, struct thread *);
851 int	ifpromisc(struct ifnet *, int);
852 struct	ifnet *ifunit(const char *);
853 struct	ifnet *ifunit_ref(const char *);
854 
855 void	ifq_init(struct ifaltq *, struct ifnet *ifp);
856 void	ifq_delete(struct ifaltq *);
857 
858 int	ifa_add_loopback_route(struct ifaddr *, struct sockaddr *);
859 int	ifa_del_loopback_route(struct ifaddr *, struct sockaddr *);
860 
861 struct	ifaddr *ifa_ifwithaddr(struct sockaddr *);
862 int		ifa_ifwithaddr_check(struct sockaddr *);
863 struct	ifaddr *ifa_ifwithbroadaddr(struct sockaddr *);
864 struct	ifaddr *ifa_ifwithdstaddr(struct sockaddr *);
865 struct	ifaddr *ifa_ifwithnet(struct sockaddr *);
866 struct	ifaddr *ifa_ifwithroute(int, struct sockaddr *, struct sockaddr *);
867 struct	ifaddr *ifa_ifwithroute_fib(int, struct sockaddr *, struct sockaddr *, u_int);
868 
869 struct	ifaddr *ifaof_ifpforaddr(struct sockaddr *, struct ifnet *);
870 
871 int	if_simloop(struct ifnet *ifp, struct mbuf *m, int af, int hlen);
872 
873 typedef	void *if_com_alloc_t(u_char type, struct ifnet *ifp);
874 typedef	void if_com_free_t(void *com, u_char type);
875 void	if_register_com_alloc(u_char type, if_com_alloc_t *a, if_com_free_t *f);
876 void	if_deregister_com_alloc(u_char type);
877 
878 #define IF_LLADDR(ifp)							\
879     LLADDR((struct sockaddr_dl *)((ifp)->if_addr->ifa_addr))
880 
881 #ifdef DEVICE_POLLING
882 enum poll_cmd {	POLL_ONLY, POLL_AND_CHECK_STATUS };
883 
884 typedef	int poll_handler_t(struct ifnet *ifp, enum poll_cmd cmd, int count);
885 int    ether_poll_register(poll_handler_t *h, struct ifnet *ifp);
886 int    ether_poll_deregister(struct ifnet *ifp);
887 #endif /* DEVICE_POLLING */
888 
889 #endif /* _KERNEL */
890 
891 #endif /* !_NET_IF_VAR_H_ */
892