1 /* 2 * vhost-user.c 3 * 4 * Copyright (c) 2013 Virtual Open Systems Sarl. 5 * 6 * This work is licensed under the terms of the GNU GPL, version 2 or later. 7 * See the COPYING file in the top-level directory. 8 * 9 */ 10 11 #include "qemu/osdep.h" 12 #include "clients.h" 13 #include "net/vhost_net.h" 14 #include "net/vhost-user.h" 15 #include "hw/virtio/vhost-user.h" 16 #include "chardev/char-fe.h" 17 #include "qapi/error.h" 18 #include "qapi/qapi-commands-net.h" 19 #include "qemu/config-file.h" 20 #include "qemu/error-report.h" 21 #include "qemu/option.h" 22 #include "trace.h" 23 24 typedef struct NetVhostUserState { 25 NetClientState nc; 26 CharBackend chr; /* only queue index 0 */ 27 VhostUserState *vhost_user; 28 VHostNetState *vhost_net; 29 guint watch; 30 uint64_t acked_features; 31 bool started; 32 } NetVhostUserState; 33 34 VHostNetState *vhost_user_get_vhost_net(NetClientState *nc) 35 { 36 NetVhostUserState *s = DO_UPCAST(NetVhostUserState, nc, nc); 37 assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER); 38 return s->vhost_net; 39 } 40 41 uint64_t vhost_user_get_acked_features(NetClientState *nc) 42 { 43 NetVhostUserState *s = DO_UPCAST(NetVhostUserState, nc, nc); 44 assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER); 45 return s->acked_features; 46 } 47 48 static void vhost_user_stop(int queues, NetClientState *ncs[]) 49 { 50 NetVhostUserState *s; 51 int i; 52 53 for (i = 0; i < queues; i++) { 54 assert(ncs[i]->info->type == NET_CLIENT_DRIVER_VHOST_USER); 55 56 s = DO_UPCAST(NetVhostUserState, nc, ncs[i]); 57 58 if (s->vhost_net) { 59 /* save acked features */ 60 uint64_t features = vhost_net_get_acked_features(s->vhost_net); 61 if (features) { 62 s->acked_features = features; 63 } 64 vhost_net_cleanup(s->vhost_net); 65 } 66 } 67 } 68 69 static int vhost_user_start(int queues, NetClientState *ncs[], 70 VhostUserState *be) 71 { 72 VhostNetOptions options; 73 struct vhost_net *net = NULL; 74 NetVhostUserState *s; 75 int max_queues; 76 int i; 77 78 options.backend_type = VHOST_BACKEND_TYPE_USER; 79 80 for (i = 0; i < queues; i++) { 81 assert(ncs[i]->info->type == NET_CLIENT_DRIVER_VHOST_USER); 82 83 s = DO_UPCAST(NetVhostUserState, nc, ncs[i]); 84 85 options.net_backend = ncs[i]; 86 options.opaque = be; 87 options.busyloop_timeout = 0; 88 net = vhost_net_init(&options); 89 if (!net) { 90 error_report("failed to init vhost_net for queue %d", i); 91 goto err; 92 } 93 94 if (i == 0) { 95 max_queues = vhost_net_get_max_queues(net); 96 if (queues > max_queues) { 97 error_report("you are asking more queues than supported: %d", 98 max_queues); 99 goto err; 100 } 101 } 102 103 if (s->vhost_net) { 104 vhost_net_cleanup(s->vhost_net); 105 g_free(s->vhost_net); 106 } 107 s->vhost_net = net; 108 } 109 110 return 0; 111 112 err: 113 if (net) { 114 vhost_net_cleanup(net); 115 g_free(net); 116 } 117 vhost_user_stop(i, ncs); 118 return -1; 119 } 120 121 static ssize_t vhost_user_receive(NetClientState *nc, const uint8_t *buf, 122 size_t size) 123 { 124 /* In case of RARP (message size is 60) notify backup to send a fake RARP. 125 This fake RARP will be sent by backend only for guest 126 without GUEST_ANNOUNCE capability. 127 */ 128 if (size == 60) { 129 NetVhostUserState *s = DO_UPCAST(NetVhostUserState, nc, nc); 130 int r; 131 static int display_rarp_failure = 1; 132 char mac_addr[6]; 133 134 /* extract guest mac address from the RARP message */ 135 memcpy(mac_addr, &buf[6], 6); 136 137 r = vhost_net_notify_migration_done(s->vhost_net, mac_addr); 138 139 if ((r != 0) && (display_rarp_failure)) { 140 fprintf(stderr, 141 "Vhost user backend fails to broadcast fake RARP\n"); 142 fflush(stderr); 143 display_rarp_failure = 0; 144 } 145 } 146 147 return size; 148 } 149 150 static void net_vhost_user_cleanup(NetClientState *nc) 151 { 152 NetVhostUserState *s = DO_UPCAST(NetVhostUserState, nc, nc); 153 154 if (s->vhost_net) { 155 vhost_net_cleanup(s->vhost_net); 156 g_free(s->vhost_net); 157 s->vhost_net = NULL; 158 } 159 if (nc->queue_index == 0) { 160 if (s->watch) { 161 g_source_remove(s->watch); 162 s->watch = 0; 163 } 164 qemu_chr_fe_deinit(&s->chr, true); 165 if (s->vhost_user) { 166 vhost_user_cleanup(s->vhost_user); 167 g_free(s->vhost_user); 168 s->vhost_user = NULL; 169 } 170 } 171 172 qemu_purge_queued_packets(nc); 173 } 174 175 static bool vhost_user_has_vnet_hdr(NetClientState *nc) 176 { 177 assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER); 178 179 return true; 180 } 181 182 static bool vhost_user_has_ufo(NetClientState *nc) 183 { 184 assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER); 185 186 return true; 187 } 188 189 static NetClientInfo net_vhost_user_info = { 190 .type = NET_CLIENT_DRIVER_VHOST_USER, 191 .size = sizeof(NetVhostUserState), 192 .receive = vhost_user_receive, 193 .cleanup = net_vhost_user_cleanup, 194 .has_vnet_hdr = vhost_user_has_vnet_hdr, 195 .has_ufo = vhost_user_has_ufo, 196 }; 197 198 static gboolean net_vhost_user_watch(GIOChannel *chan, GIOCondition cond, 199 void *opaque) 200 { 201 NetVhostUserState *s = opaque; 202 203 qemu_chr_fe_disconnect(&s->chr); 204 205 return TRUE; 206 } 207 208 static void net_vhost_user_event(void *opaque, int event); 209 210 static void chr_closed_bh(void *opaque) 211 { 212 const char *name = opaque; 213 NetClientState *ncs[MAX_QUEUE_NUM]; 214 NetVhostUserState *s; 215 Error *err = NULL; 216 int queues; 217 218 queues = qemu_find_net_clients_except(name, ncs, 219 NET_CLIENT_DRIVER_NIC, 220 MAX_QUEUE_NUM); 221 assert(queues < MAX_QUEUE_NUM); 222 223 s = DO_UPCAST(NetVhostUserState, nc, ncs[0]); 224 225 qmp_set_link(name, false, &err); 226 vhost_user_stop(queues, ncs); 227 228 qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, net_vhost_user_event, 229 NULL, opaque, NULL, true); 230 231 if (err) { 232 error_report_err(err); 233 } 234 } 235 236 static void net_vhost_user_event(void *opaque, int event) 237 { 238 const char *name = opaque; 239 NetClientState *ncs[MAX_QUEUE_NUM]; 240 NetVhostUserState *s; 241 Chardev *chr; 242 Error *err = NULL; 243 int queues; 244 245 queues = qemu_find_net_clients_except(name, ncs, 246 NET_CLIENT_DRIVER_NIC, 247 MAX_QUEUE_NUM); 248 assert(queues < MAX_QUEUE_NUM); 249 250 s = DO_UPCAST(NetVhostUserState, nc, ncs[0]); 251 chr = qemu_chr_fe_get_driver(&s->chr); 252 trace_vhost_user_event(chr->label, event); 253 switch (event) { 254 case CHR_EVENT_OPENED: 255 if (vhost_user_start(queues, ncs, s->vhost_user) < 0) { 256 qemu_chr_fe_disconnect(&s->chr); 257 return; 258 } 259 s->watch = qemu_chr_fe_add_watch(&s->chr, G_IO_HUP, 260 net_vhost_user_watch, s); 261 qmp_set_link(name, true, &err); 262 s->started = true; 263 break; 264 case CHR_EVENT_CLOSED: 265 /* a close event may happen during a read/write, but vhost 266 * code assumes the vhost_dev remains setup, so delay the 267 * stop & clear to idle. 268 * FIXME: better handle failure in vhost code, remove bh 269 */ 270 if (s->watch) { 271 AioContext *ctx = qemu_get_current_aio_context(); 272 273 g_source_remove(s->watch); 274 s->watch = 0; 275 qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, NULL, NULL, 276 NULL, NULL, false); 277 278 aio_bh_schedule_oneshot(ctx, chr_closed_bh, opaque); 279 } 280 break; 281 } 282 283 if (err) { 284 error_report_err(err); 285 } 286 } 287 288 static int net_vhost_user_init(NetClientState *peer, const char *device, 289 const char *name, Chardev *chr, 290 int queues) 291 { 292 Error *err = NULL; 293 NetClientState *nc, *nc0 = NULL; 294 VhostUserState *user = NULL; 295 NetVhostUserState *s = NULL; 296 int i; 297 298 assert(name); 299 assert(queues > 0); 300 301 user = vhost_user_init(); 302 if (!user) { 303 error_report("failed to init vhost_user"); 304 goto err; 305 } 306 307 for (i = 0; i < queues; i++) { 308 nc = qemu_new_net_client(&net_vhost_user_info, peer, device, name); 309 snprintf(nc->info_str, sizeof(nc->info_str), "vhost-user%d to %s", 310 i, chr->label); 311 nc->queue_index = i; 312 if (!nc0) { 313 nc0 = nc; 314 s = DO_UPCAST(NetVhostUserState, nc, nc); 315 if (!qemu_chr_fe_init(&s->chr, chr, &err)) { 316 error_report_err(err); 317 goto err; 318 } 319 user->chr = &s->chr; 320 } 321 s = DO_UPCAST(NetVhostUserState, nc, nc); 322 s->vhost_user = user; 323 } 324 325 s = DO_UPCAST(NetVhostUserState, nc, nc0); 326 do { 327 if (qemu_chr_fe_wait_connected(&s->chr, &err) < 0) { 328 error_report_err(err); 329 goto err; 330 } 331 qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, 332 net_vhost_user_event, NULL, nc0->name, NULL, 333 true); 334 } while (!s->started); 335 336 assert(s->vhost_net); 337 338 return 0; 339 340 err: 341 if (user) { 342 vhost_user_cleanup(user); 343 g_free(user); 344 if (s) { 345 s->vhost_user = NULL; 346 } 347 } 348 if (nc0) { 349 qemu_del_net_client(nc0); 350 } 351 352 return -1; 353 } 354 355 static Chardev *net_vhost_claim_chardev( 356 const NetdevVhostUserOptions *opts, Error **errp) 357 { 358 Chardev *chr = qemu_chr_find(opts->chardev); 359 360 if (chr == NULL) { 361 error_setg(errp, "chardev \"%s\" not found", opts->chardev); 362 return NULL; 363 } 364 365 if (!qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_RECONNECTABLE)) { 366 error_setg(errp, "chardev \"%s\" is not reconnectable", 367 opts->chardev); 368 return NULL; 369 } 370 if (!qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_FD_PASS)) { 371 error_setg(errp, "chardev \"%s\" does not support FD passing", 372 opts->chardev); 373 return NULL; 374 } 375 376 return chr; 377 } 378 379 static int net_vhost_check_net(void *opaque, QemuOpts *opts, Error **errp) 380 { 381 const char *name = opaque; 382 const char *driver, *netdev; 383 384 driver = qemu_opt_get(opts, "driver"); 385 netdev = qemu_opt_get(opts, "netdev"); 386 387 if (!driver || !netdev) { 388 return 0; 389 } 390 391 if (strcmp(netdev, name) == 0 && 392 !g_str_has_prefix(driver, "virtio-net-")) { 393 error_setg(errp, "vhost-user requires frontend driver virtio-net-*"); 394 return -1; 395 } 396 397 return 0; 398 } 399 400 int net_init_vhost_user(const Netdev *netdev, const char *name, 401 NetClientState *peer, Error **errp) 402 { 403 int queues; 404 const NetdevVhostUserOptions *vhost_user_opts; 405 Chardev *chr; 406 407 assert(netdev->type == NET_CLIENT_DRIVER_VHOST_USER); 408 vhost_user_opts = &netdev->u.vhost_user; 409 410 chr = net_vhost_claim_chardev(vhost_user_opts, errp); 411 if (!chr) { 412 return -1; 413 } 414 415 /* verify net frontend */ 416 if (qemu_opts_foreach(qemu_find_opts("device"), net_vhost_check_net, 417 (char *)name, errp)) { 418 return -1; 419 } 420 421 queues = vhost_user_opts->has_queues ? vhost_user_opts->queues : 1; 422 if (queues < 1 || queues > MAX_QUEUE_NUM) { 423 error_setg(errp, 424 "vhost-user number of queues must be in range [1, %d]", 425 MAX_QUEUE_NUM); 426 return -1; 427 } 428 429 return net_vhost_user_init(peer, "vhost_user", name, chr, queues); 430 } 431