if_virt.c revision 1.31
1 /* $NetBSD: if_virt.c,v 1.31 2013/04/30 00:03:54 pooka Exp $ */ 2 3 /* 4 * Copyright (c) 2008 Antti Kantee. 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 THE AUTHOR ``AS IS'' AND ANY EXPRESS 16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 18 * DISCLAIMED. IN NO EVENT SHALL THE 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 OR 21 * 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 28 #include <sys/cdefs.h> 29 __KERNEL_RCSID(0, "$NetBSD: if_virt.c,v 1.31 2013/04/30 00:03:54 pooka Exp $"); 30 31 #include <sys/param.h> 32 #include <sys/condvar.h> 33 #include <sys/fcntl.h> 34 #include <sys/kernel.h> 35 #include <sys/kmem.h> 36 #include <sys/kthread.h> 37 #include <sys/mutex.h> 38 #include <sys/poll.h> 39 #include <sys/sockio.h> 40 #include <sys/socketvar.h> 41 #include <sys/cprng.h> 42 43 #include <net/bpf.h> 44 #include <net/if.h> 45 #include <net/if_ether.h> 46 #include <net/if_tap.h> 47 48 #include <netinet/in.h> 49 #include <netinet/in_var.h> 50 51 #include <rump/rump.h> 52 53 #include "rump_private.h" 54 #include "rump_net_private.h" 55 56 #include "rumpcomp_user.h" 57 58 /* 59 * Virtual interface for userspace purposes. Uses tap(4) to 60 * interface with the kernel and just simply shovels data 61 * to/from /dev/tap. 62 */ 63 64 #define VIRTIF_BASE "virt" 65 66 static int virtif_init(struct ifnet *); 67 static int virtif_ioctl(struct ifnet *, u_long, void *); 68 static void virtif_start(struct ifnet *); 69 static void virtif_stop(struct ifnet *, int); 70 71 struct virtif_sc { 72 struct ethercom sc_ec; 73 struct virtif_user *sc_viu; 74 bool sc_dying; 75 struct lwp *sc_l_snd, *sc_l_rcv; 76 kmutex_t sc_mtx; 77 kcondvar_t sc_cv; 78 }; 79 80 static void virtif_receiver(void *); 81 static void virtif_sender(void *); 82 static int virtif_clone(struct if_clone *, int); 83 static int virtif_unclone(struct ifnet *); 84 85 struct if_clone virtif_cloner = 86 IF_CLONE_INITIALIZER(VIRTIF_BASE, virtif_clone, virtif_unclone); 87 88 int 89 rump_virtif_create(int num) 90 { 91 struct virtif_sc *sc; 92 struct virtif_user *viu; 93 struct ifnet *ifp; 94 uint8_t enaddr[ETHER_ADDR_LEN] = { 0xb2, 0x0a, 0x00, 0x0b, 0x0e, 0x01 }; 95 int error = 0; 96 97 if (num >= 0x100) 98 return E2BIG; 99 100 if ((error = rumpcomp_virtif_create(num, &viu)) != 0) 101 return error; 102 103 enaddr[2] = cprng_fast32() & 0xff; 104 enaddr[5] = num; 105 106 sc = kmem_zalloc(sizeof(*sc), KM_SLEEP); 107 sc->sc_dying = false; 108 sc->sc_viu = viu; 109 110 mutex_init(&sc->sc_mtx, MUTEX_DEFAULT, IPL_NONE); 111 cv_init(&sc->sc_cv, "virtsnd"); 112 ifp = &sc->sc_ec.ec_if; 113 sprintf(ifp->if_xname, "%s%d", VIRTIF_BASE, num); 114 ifp->if_softc = sc; 115 116 if (rump_threads) { 117 if ((error = kthread_create(PRI_NONE, KTHREAD_MUSTJOIN, NULL, 118 virtif_receiver, ifp, &sc->sc_l_rcv, "virtifr")) != 0) 119 goto out; 120 121 if ((error = kthread_create(PRI_NONE, 122 KTHREAD_MUSTJOIN | KTHREAD_MPSAFE, NULL, 123 virtif_sender, ifp, &sc->sc_l_snd, "virtifs")) != 0) 124 goto out; 125 } else { 126 printf("WARNING: threads not enabled, receive NOT working\n"); 127 } 128 129 ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; 130 ifp->if_init = virtif_init; 131 ifp->if_ioctl = virtif_ioctl; 132 ifp->if_start = virtif_start; 133 ifp->if_stop = virtif_stop; 134 IFQ_SET_READY(&ifp->if_snd); 135 136 if_attach(ifp); 137 ether_ifattach(ifp, enaddr); 138 139 out: 140 if (error) { 141 virtif_unclone(ifp); 142 } 143 144 return error; 145 } 146 147 static int 148 virtif_clone(struct if_clone *ifc, int unit) 149 { 150 151 return rump_virtif_create(unit); 152 } 153 154 static int 155 virtif_unclone(struct ifnet *ifp) 156 { 157 struct virtif_sc *sc = ifp->if_softc; 158 159 mutex_enter(&sc->sc_mtx); 160 if (sc->sc_dying) { 161 mutex_exit(&sc->sc_mtx); 162 return EINPROGRESS; 163 } 164 sc->sc_dying = true; 165 cv_broadcast(&sc->sc_cv); 166 mutex_exit(&sc->sc_mtx); 167 168 rumpcomp_virtif_dying(sc->sc_viu); 169 170 virtif_stop(ifp, 1); 171 if_down(ifp); 172 173 if (sc->sc_l_snd) { 174 kthread_join(sc->sc_l_snd); 175 sc->sc_l_snd = NULL; 176 } 177 if (sc->sc_l_rcv) { 178 kthread_join(sc->sc_l_rcv); 179 sc->sc_l_rcv = NULL; 180 } 181 182 rumpcomp_virtif_destroy(sc->sc_viu); 183 184 mutex_destroy(&sc->sc_mtx); 185 cv_destroy(&sc->sc_cv); 186 kmem_free(sc, sizeof(*sc)); 187 188 ether_ifdetach(ifp); 189 if_detach(ifp); 190 191 return 0; 192 } 193 194 static int 195 virtif_init(struct ifnet *ifp) 196 { 197 struct virtif_sc *sc = ifp->if_softc; 198 199 ifp->if_flags |= IFF_RUNNING; 200 201 mutex_enter(&sc->sc_mtx); 202 cv_broadcast(&sc->sc_cv); 203 mutex_exit(&sc->sc_mtx); 204 205 return 0; 206 } 207 208 static int 209 virtif_ioctl(struct ifnet *ifp, u_long cmd, void *data) 210 { 211 int s, rv; 212 213 s = splnet(); 214 rv = ether_ioctl(ifp, cmd, data); 215 if (rv == ENETRESET) 216 rv = 0; 217 splx(s); 218 219 return rv; 220 } 221 222 static void 223 virtif_start(struct ifnet *ifp) 224 { 225 struct virtif_sc *sc = ifp->if_softc; 226 227 mutex_enter(&sc->sc_mtx); 228 ifp->if_flags |= IFF_OACTIVE; 229 cv_broadcast(&sc->sc_cv); 230 mutex_exit(&sc->sc_mtx); 231 } 232 233 static void 234 virtif_stop(struct ifnet *ifp, int disable) 235 { 236 struct virtif_sc *sc = ifp->if_softc; 237 238 ifp->if_flags &= ~IFF_RUNNING; 239 240 mutex_enter(&sc->sc_mtx); 241 cv_broadcast(&sc->sc_cv); 242 mutex_exit(&sc->sc_mtx); 243 } 244 245 #define POLLTIMO_MS 1 246 static void 247 virtif_receiver(void *arg) 248 { 249 struct ifnet *ifp = arg; 250 struct virtif_sc *sc = ifp->if_softc; 251 struct mbuf *m; 252 size_t plen = ETHER_MAX_LEN_JUMBO+1; 253 size_t n; 254 int error; 255 256 for (;;) { 257 m = m_gethdr(M_WAIT, MT_DATA); 258 MEXTMALLOC(m, plen, M_WAIT); 259 260 again: 261 if (sc->sc_dying) { 262 m_freem(m); 263 break; 264 } 265 266 error = rumpcomp_virtif_recv(sc->sc_viu, 267 mtod(m, void *), plen, &n); 268 if (error) { 269 printf("%s: read hypercall failed %d. host if down?\n", 270 ifp->if_xname, error); 271 mutex_enter(&sc->sc_mtx); 272 /* could check if need go, done soon anyway */ 273 cv_timedwait(&sc->sc_cv, &sc->sc_mtx, hz); 274 mutex_exit(&sc->sc_mtx); 275 goto again; 276 } 277 278 /* tap sometimes returns EOF. don't sweat it and plow on */ 279 if (__predict_false(n == 0)) 280 goto again; 281 282 /* discard if we're not up */ 283 if ((ifp->if_flags & IFF_RUNNING) == 0) 284 goto again; 285 286 m->m_len = m->m_pkthdr.len = n; 287 m->m_pkthdr.rcvif = ifp; 288 bpf_mtap(ifp, m); 289 ether_input(ifp, m); 290 } 291 292 kthread_exit(0); 293 } 294 295 /* lazy bum stetson-harrison magic value */ 296 #define LB_SH 32 297 static void 298 virtif_sender(void *arg) 299 { 300 struct ifnet *ifp = arg; 301 struct virtif_sc *sc = ifp->if_softc; 302 struct mbuf *m, *m0; 303 struct iovec io[LB_SH]; 304 int i; 305 306 mutex_enter(&sc->sc_mtx); 307 KERNEL_LOCK(1, NULL); 308 while (!sc->sc_dying) { 309 if (!(ifp->if_flags & IFF_RUNNING)) { 310 cv_wait(&sc->sc_cv, &sc->sc_mtx); 311 continue; 312 } 313 IF_DEQUEUE(&ifp->if_snd, m0); 314 if (!m0) { 315 ifp->if_flags &= ~IFF_OACTIVE; 316 cv_wait(&sc->sc_cv, &sc->sc_mtx); 317 continue; 318 } 319 mutex_exit(&sc->sc_mtx); 320 321 m = m0; 322 for (i = 0; i < LB_SH && m; i++) { 323 io[i].iov_base = mtod(m, void *); 324 io[i].iov_len = m->m_len; 325 m = m->m_next; 326 } 327 if (i == LB_SH) 328 panic("lazy bum"); 329 bpf_mtap(ifp, m0); 330 331 rumpcomp_virtif_send(sc->sc_viu, io, i); 332 333 m_freem(m0); 334 mutex_enter(&sc->sc_mtx); 335 } 336 KERNEL_UNLOCK_LAST(curlwp); 337 338 mutex_exit(&sc->sc_mtx); 339 340 kthread_exit(0); 341 } 342 343 /* 344 * dummyif is a nada-interface. 345 * As it requires nothing external, it can be used for testing 346 * interface configuration. 347 */ 348 static int dummyif_init(struct ifnet *); 349 static void dummyif_start(struct ifnet *); 350 351 void 352 rump_dummyif_create() 353 { 354 struct ifnet *ifp; 355 struct ethercom *ec; 356 uint8_t enaddr[ETHER_ADDR_LEN] = { 0xb2, 0x0a, 0x00, 0x0b, 0x0e, 0x01 }; 357 358 enaddr[2] = cprng_fast32() & 0xff; 359 enaddr[5] = cprng_fast32() & 0xff; 360 361 ec = kmem_zalloc(sizeof(*ec), KM_SLEEP); 362 363 ifp = &ec->ec_if; 364 strlcpy(ifp->if_xname, "dummy0", sizeof(ifp->if_xname)); 365 ifp->if_softc = ifp; 366 ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; 367 ifp->if_init = dummyif_init; 368 ifp->if_ioctl = virtif_ioctl; 369 ifp->if_start = dummyif_start; 370 371 if_attach(ifp); 372 ether_ifattach(ifp, enaddr); 373 } 374 375 static int 376 dummyif_init(struct ifnet *ifp) 377 { 378 379 ifp->if_flags |= IFF_RUNNING; 380 return 0; 381 } 382 383 static void 384 dummyif_start(struct ifnet *ifp) 385 { 386 387 } 388
Indexes created Fri Sep 26 20:09:58 GMT 2025