1/*	$NetBSD: if_vlanvar.h,v 1.17 2022/06/20 08:02:25 yamaguchi Exp $	*/
  2
  3/*
  4 * Copyright (c) 2000 The NetBSD Foundation, Inc.
  5 * All rights reserved.
  6 *
  7 * This code is derived from software contributed to The NetBSD Foundation
  8 * by Andrew Doran.
  9 *
 10 * Redistribution and use in source and binary forms, with or without
 11 * modification, are permitted provided that the following conditions
 12 * are met:
 13 * 1. Redistributions of source code must retain the above copyright
 14 *    notice, this list of conditions and the following disclaimer.
 15 * 2. Redistributions in binary form must reproduce the above copyright
 16 *    notice, this list of conditions and the following disclaimer in the
 17 *    documentation and/or other materials provided with the distribution.
 18 *
 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 29 * POSSIBILITY OF SUCH DAMAGE.
 30 */
 31
 32/*
 33 * Copyright 1998 Massachusetts Institute of Technology
 34 *
 35 * Permission to use, copy, modify, and distribute this software and
 36 * its documentation for any purpose and without fee is hereby
 37 * granted, provided that both the above copyright notice and this
 38 * permission notice appear in all copies, that both the above
 39 * copyright notice and this permission notice appear in all
 40 * supporting documentation, and that the name of M.I.T. not be used
 41 * in advertising or publicity pertaining to distribution of the
 42 * software without specific, written prior permission.  M.I.T. makes
 43 * no representations about the suitability of this software for any
 44 * purpose.  It is provided "as is" without express or implied
 45 * warranty.
 46 *
 47 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
 48 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
 49 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 50 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
 51 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 52 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 53 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 54 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 55 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 56 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 57 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 58 * SUCH DAMAGE.
 59 *
 60 * from FreeBSD: if_vlan_var.h,v 1.3 1999/08/28 00:48:24 peter Exp
 61 */
 62
 63#ifndef _NET_IF_VLANVAR_H_
 64#define	_NET_IF_VLANVAR_H_
 65
 66struct ether_vlan_header {
 67	uint8_t		evl_dhost[ETHER_ADDR_LEN];
 68	uint8_t		evl_shost[ETHER_ADDR_LEN];
 69	uint16_t	evl_encap_proto;
 70	uint16_t	evl_tag;
 71	uint16_t	evl_proto;
 72} __packed;
 73
 74/* Configuration structure for SIOCSETVLAN and SIOCGETVLAN ioctls. */
 75struct vlanreq {
 76	char		vlr_parent[IFNAMSIZ];
 77	uint16_t	vlr_tag;
 78};
 79
 80#define	SIOCSETVLAN	SIOCSIFGENERIC
 81#define	SIOCGETVLAN	SIOCGIFGENERIC
 82
 83#ifdef _KERNEL
 84struct mbuf *	vlan_input(struct ifnet *, struct mbuf *);
 85
 86/*
 87 * Locking notes:
 88 * + ifv_list.list is protected by ifv_list.lock (an adaptive mutex)
 89 *     ifv_list.list is list of all ifvlans, and it is used to avoid
 90 *     unload while busy.
 91 * + ifv_hash.lists is protected by
 92 *   - ifv_hash.lock (an adaptive mutex) for writer
 93 *   - pserialize for reader
 94 *     ifv_hash.lists is hashed list of all configured
 95 *     vlan interface, and it is used to avoid unload while busy.
 96 * + ifvlan->ifv_linkmib is protected by
 97 *   - ifvlan->ifv_lock (an adaptive mutex) for writer
 98 *   - ifv_linkmib->ifvm_psref for reader
 99 *     ifvlan->ifv_linkmib is used for variant values while tagging
100 *     and untagging
101 *
102 * Locking order:
103 *     - ifv_list.lock => struct ifvlan->ifv_lock
104 *     - struct ifvlan->ifv_lock => ifv_hash.lock
105 * Other mutexes must not hold simultaneously
106 *
107 *   NOTICE
108 *     - ifvlan must not have a variant value while tagging and
109 *       untagging. Such variant values must be in ifvlan->ifv_mib
110 *     - ifvlan->ifv_mib is modified like read-copy-update.
111 *       So, once we dereference ifvlan->ifv_mib,
112 *       we must keep the pointer during the same context. If we
113 *       re-dereference ifvlan->ifv_mib, the ifv_mib may be other
114 *       one because of concurrent writer processing.
115 */
116#endif	/* _KERNEL */
117
118#endif	/* !_NET_IF_VLANVAR_H_ */