1 /* $NetBSD: if_gif.h,v 1.31 2018/04/27 09:55:27 knakahara Exp $ */ 2 /* $KAME: if_gif.h,v 1.23 2001/07/27 09:21:42 itojun Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * if_gif.h 35 */ 36 37 #ifndef _NET_IF_GIF_H_ 38 #define _NET_IF_GIF_H_ 39 40 #include <sys/queue.h> 41 #include <sys/percpu.h> 42 #ifdef _KERNEL 43 #include <sys/psref.h> 44 #endif 45 46 #ifdef _KERNEL_OPT 47 #include "opt_inet.h" 48 #endif 49 50 #include <netinet/in.h> 51 /* xxx sigh, why route have struct route instead of pointer? */ 52 53 extern struct psref_class *gv_psref_class; 54 55 struct encaptab; 56 57 struct gif_ro { 58 struct route gr_ro; 59 kmutex_t *gr_lock; 60 }; 61 62 struct gif_variant { 63 struct gif_softc *gv_softc; 64 struct sockaddr *gv_psrc; /* Physical src addr */ 65 struct sockaddr *gv_pdst; /* Physical dst addr */ 66 const struct encaptab *gv_encap_cookie4; 67 const struct encaptab *gv_encap_cookie6; 68 int (*gv_output)(struct gif_variant *, int, struct mbuf *); 69 70 struct psref_target gv_psref; 71 }; 72 73 struct gif_softc { 74 struct ifnet gif_if; /* common area - must be at the top */ 75 percpu_t *gif_ro_percpu; /* struct gif_ro */ 76 struct gif_variant *gif_var; /* 77 * reader must use gif_getref_variant() 78 * instead of direct dereference. 79 */ 80 kmutex_t gif_lock; /* writer lock for gif_var */ 81 82 LIST_ENTRY(gif_softc) gif_list; /* list of all gifs */ 83 }; 84 #define GIF_ROUTE_TTL 10 85 86 #define GIF_MTU (1280) /* Default MTU */ 87 #define GIF_MTU_MIN (1280) /* Minimum MTU */ 88 #define GIF_MTU_MAX (8192) /* Maximum MTU */ 89 90 /* 91 * Get gif_variant from gif_softc. 92 * 93 * Never return NULL by contract. 94 * gif_variant itself is protected not to be freed by gv_psref. 95 * Once a reader dereference sc->sc_var by this API, the reader must not 96 * re-dereference form sc->sc_var. 97 */ 98 static __inline struct gif_variant * 99 gif_getref_variant(struct gif_softc *sc, struct psref *psref) 100 { 101 struct gif_variant *var; 102 int s; 103 104 s = pserialize_read_enter(); 105 var = sc->gif_var; 106 KASSERT(var != NULL); 107 membar_datadep_consumer(); 108 psref_acquire(psref, &var->gv_psref, gv_psref_class); 109 pserialize_read_exit(s); 110 111 return var; 112 } 113 114 static __inline void 115 gif_putref_variant(struct gif_variant *var, struct psref *psref) 116 { 117 118 KASSERT(var != NULL); 119 psref_release(psref, &var->gv_psref, gv_psref_class); 120 } 121 122 static __inline bool 123 gif_heldref_variant(struct gif_variant *var) 124 { 125 126 return psref_held(&var->gv_psref, gv_psref_class); 127 } 128 129 /* Prototypes */ 130 void gif_input(struct mbuf *, int, struct ifnet *); 131 132 void gif_rtcache_free_pc(void *, void *, struct cpu_info *); 133 134 #ifdef GIF_ENCAPCHECK 135 int gif_encapcheck(struct mbuf *, int, int, void *); 136 #endif 137 138 /* 139 * Locking notes: 140 * + gif_softc_list is protected by gif_softcs.lock (an adaptive mutex) 141 * gif_softc_list is list of all gif_softcs. It is used by ioctl 142 * context only. 143 * + gif_softc->gif_var is protected by 144 * - gif_softc->gif_lock (an adaptive mutex) for writer 145 * - gif_var->gv_psref for reader 146 * gif_softc->gif_var is used for variant values while the gif tunnel 147 * exists. 148 * + Each CPU's gif_ro.gr_ro of gif_ro_percpu are protected by 149 * percpu'ed gif_ro.gr_lock. 150 * 151 * Locking order: 152 * - encap_lock => gif_softc->gif_lock => gif_softcs.lock 153 */ 154 #endif /* !_NET_IF_GIF_H_ */ 155