if_virt.c revision 1.35
1 /* $NetBSD: if_virt.c,v 1.35 2013/07/03 20:17:07 pooka Exp $ */ 2 3 /* 4 * Copyright (c) 2008, 2013 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 1.35 2013/07/03 20:17:07 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. Uses hypercalls to shovel packets back 60 * and forth. The exact method for shoveling depends on the 61 * hypercall implementation. 62 */ 63 64 #ifndef VIRTIF_BASE 65 #define VIRTIF_BASE "virt" 66 #endif 67 68 static int virtif_init(struct ifnet *); 69 static int virtif_ioctl(struct ifnet *, u_long, void *); 70 static void virtif_start(struct ifnet *); 71 static void virtif_stop(struct ifnet *, int); 72 73 struct virtif_sc { 74 struct ethercom sc_ec; 75 struct virtif_user *sc_viu; 76 bool sc_dying; 77 struct lwp *sc_l_snd, *sc_l_rcv; 78 kmutex_t sc_mtx; 79 kcondvar_t sc_cv; 80 }; 81 82 static void virtif_receiver(void *); 83 static void virtif_sender(void *); 84 static int virtif_clone(struct if_clone *, int); 85 static int virtif_unclone(struct ifnet *); 86 87 struct if_clone virtif_cloner = 88 IF_CLONE_INITIALIZER(VIRTIF_BASE, virtif_clone, virtif_unclone); 89 90 static int 91 virtif_clone(struct if_clone *ifc, int num) 92 { 93 struct virtif_sc *sc; 94 struct virtif_user *viu; 95 struct ifnet *ifp; 96 uint8_t enaddr[ETHER_ADDR_LEN] = { 0xb2, 0x0a, 0x00, 0x0b, 0x0e, 0x01 }; 97 int error = 0; 98 99 if (num >= 0x100) 100 return E2BIG; 101 102 if ((error = rumpcomp_virtif_create(num, &viu)) != 0) 103 return error; 104 105 enaddr[2] = cprng_fast32() & 0xff; 106 enaddr[5] = num; 107 108 sc = kmem_zalloc(sizeof(*sc), KM_SLEEP); 109 sc->sc_dying = false; 110 sc->sc_viu = viu; 111 112 mutex_init(&sc->sc_mtx, MUTEX_DEFAULT, IPL_NONE); 113 cv_init(&sc->sc_cv, VIRTIF_BASE "snd"); 114 ifp = &sc->sc_ec.ec_if; 115 sprintf(ifp->if_xname, "%s%d", VIRTIF_BASE, num); 116 ifp->if_softc = sc; 117 118 if (rump_threads) { 119 if ((error = kthread_create(PRI_NONE, KTHREAD_MUSTJOIN, NULL, 120 virtif_receiver, ifp, &sc->sc_l_rcv, 121 VIRTIF_BASE "ifr")) != 0) 122 goto out; 123 124 if ((error = kthread_create(PRI_NONE, 125 KTHREAD_MUSTJOIN | KTHREAD_MPSAFE, NULL, 126 virtif_sender, ifp, &sc->sc_l_snd, VIRTIF_BASE "ifs")) != 0) 127 goto out; 128 } else { 129 printf("WARNING: threads not enabled, receive NOT working\n"); 130 } 131 132 ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; 133 ifp->if_init = virtif_init; 134 ifp->if_ioctl = virtif_ioctl; 135 ifp->if_start = virtif_start; 136 ifp->if_stop = virtif_stop; 137 IFQ_SET_READY(&ifp->if_snd); 138 139 if_attach(ifp); 140 ether_ifattach(ifp, enaddr); 141 142 out: 143 if (error) { 144 virtif_unclone(ifp); 145 } 146 147 return error; 148 } 149 150 static int 151 virtif_unclone(struct ifnet *ifp) 152 { 153 struct virtif_sc *sc = ifp->if_softc; 154 155 mutex_enter(&sc->sc_mtx); 156 if (sc->sc_dying) { 157 mutex_exit(&sc->sc_mtx); 158 return EINPROGRESS; 159 } 160 sc->sc_dying = true; 161 cv_broadcast(&sc->sc_cv); 162 mutex_exit(&sc->sc_mtx); 163 164 rumpcomp_virtif_dying(sc->sc_viu); 165 166 virtif_stop(ifp, 1); 167 if_down(ifp); 168 169 if (sc->sc_l_snd) { 170 kthread_join(sc->sc_l_snd); 171 sc->sc_l_snd = NULL; 172 } 173 if (sc->sc_l_rcv) { 174 kthread_join(sc->sc_l_rcv); 175 sc->sc_l_rcv = NULL; 176 } 177 178 rumpcomp_virtif_destroy(sc->sc_viu); 179 180 mutex_destroy(&sc->sc_mtx); 181 cv_destroy(&sc->sc_cv); 182 kmem_free(sc, sizeof(*sc)); 183 184 ether_ifdetach(ifp); 185 if_detach(ifp); 186 187 return 0; 188 } 189 190 static int 191 virtif_init(struct ifnet *ifp) 192 { 193 struct virtif_sc *sc = ifp->if_softc; 194 195 ifp->if_flags |= IFF_RUNNING; 196 197 mutex_enter(&sc->sc_mtx); 198 cv_broadcast(&sc->sc_cv); 199 mutex_exit(&sc->sc_mtx); 200 201 return 0; 202 } 203 204 static int 205 virtif_ioctl(struct ifnet *ifp, u_long cmd, void *data) 206 { 207 int s, rv; 208 209 s = splnet(); 210 rv = ether_ioctl(ifp, cmd, data); 211 if (rv == ENETRESET) 212 rv = 0; 213 splx(s); 214 215 return rv; 216 } 217 218 static void 219 virtif_start(struct ifnet *ifp) 220 { 221 struct virtif_sc *sc = ifp->if_softc; 222 223 mutex_enter(&sc->sc_mtx); 224 ifp->if_flags |= IFF_OACTIVE; 225 cv_broadcast(&sc->sc_cv); 226 mutex_exit(&sc->sc_mtx); 227 } 228 229 static void 230 virtif_stop(struct ifnet *ifp, int disable) 231 { 232 struct virtif_sc *sc = ifp->if_softc; 233 234 ifp->if_flags &= ~IFF_RUNNING; 235 236 mutex_enter(&sc->sc_mtx); 237 cv_broadcast(&sc->sc_cv); 238 mutex_exit(&sc->sc_mtx); 239 } 240 241 #define POLLTIMO_MS 1 242 static void 243 virtif_receiver(void *arg) 244 { 245 struct ifnet *ifp = arg; 246 struct virtif_sc *sc = ifp->if_softc; 247 struct mbuf *m; 248 size_t plen = ETHER_MAX_LEN_JUMBO+1; 249 size_t n; 250 int error; 251 252 for (;;) { 253 m = m_gethdr(M_WAIT, MT_DATA); 254 MEXTMALLOC(m, plen, M_WAIT); 255 256 again: 257 if (sc->sc_dying) { 258 m_freem(m); 259 break; 260 } 261 262 error = rumpcomp_virtif_recv(sc->sc_viu, 263 mtod(m, void *), plen, &n); 264 if (error) { 265 printf("%s: read hypercall failed %d. host if down?\n", 266 ifp->if_xname, error); 267 mutex_enter(&sc->sc_mtx); 268 /* could check if need go, done soon anyway */ 269 cv_timedwait(&sc->sc_cv, &sc->sc_mtx, hz); 270 mutex_exit(&sc->sc_mtx); 271 goto again; 272 } 273 274 /* tap sometimes returns EOF. don't sweat it and plow on */ 275 if (__predict_false(n == 0)) 276 goto again; 277 278 /* discard if we're not up */ 279 if ((ifp->if_flags & IFF_RUNNING) == 0) 280 goto again; 281 282 m->m_len = m->m_pkthdr.len = n; 283 m->m_pkthdr.rcvif = ifp; 284 bpf_mtap(ifp, m); 285 ether_input(ifp, m); 286 } 287 288 kthread_exit(0); 289 } 290 291 /* lazy bum stetson-harrison magic value */ 292 #define LB_SH 32 293 static void 294 virtif_sender(void *arg) 295 { 296 struct ifnet *ifp = arg; 297 struct virtif_sc *sc = ifp->if_softc; 298 struct mbuf *m, *m0; 299 struct iovec io[LB_SH]; 300 int i; 301 302 mutex_enter(&sc->sc_mtx); 303 KERNEL_LOCK(1, NULL); 304 while (!sc->sc_dying) { 305 if (!(ifp->if_flags & IFF_RUNNING)) { 306 cv_wait(&sc->sc_cv, &sc->sc_mtx); 307 continue; 308 } 309 IF_DEQUEUE(&ifp->if_snd, m0); 310 if (!m0) { 311 ifp->if_flags &= ~IFF_OACTIVE; 312 cv_wait(&sc->sc_cv, &sc->sc_mtx); 313 continue; 314 } 315 mutex_exit(&sc->sc_mtx); 316 317 m = m0; 318 for (i = 0; i < LB_SH && m; i++) { 319 io[i].iov_base = mtod(m, void *); 320 io[i].iov_len = m->m_len; 321 m = m->m_next; 322 } 323 if (i == LB_SH) 324 panic("lazy bum"); 325 bpf_mtap(ifp, m0); 326 327 rumpcomp_virtif_send(sc->sc_viu, io, i); 328 329 m_freem(m0); 330 mutex_enter(&sc->sc_mtx); 331 } 332 KERNEL_UNLOCK_LAST(curlwp); 333 334 mutex_exit(&sc->sc_mtx); 335 336 kthread_exit(0); 337 } 338
Indexes created Thu Sep 25 16:09:42 GMT 2025