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 "qapi/qapi-events-net.h" 20 #include "qemu/config-file.h" 21 #include "qemu/error-report.h" 22 #include "qemu/option.h" 23 #include "trace.h" 24 25 typedef struct NetVhostUserState { 26 NetClientState nc; 27 CharBackend chr; /* only queue index 0 */ 28 VhostUserState *vhost_user; 29 VHostNetState *vhost_net; 30 guint watch; 31 uint64_t acked_features; 32 bool started; 33 } NetVhostUserState; 34 35 VHostNetState *vhost_user_get_vhost_net(NetClientState *nc) 36 { 37 NetVhostUserState *s = DO_UPCAST(NetVhostUserState, nc, nc); 38 assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER); 39 return s->vhost_net; 40 } 41 42 uint64_t vhost_user_get_acked_features(NetClientState *nc) 43 { 44 NetVhostUserState *s = DO_UPCAST(NetVhostUserState, nc, nc); 45 assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER); 46 return s->acked_features; 47 } 48 49 void vhost_user_save_acked_features(NetClientState *nc) 50 { 51 NetVhostUserState *s; 52 53 s = DO_UPCAST(NetVhostUserState, nc, nc); 54 if (s->vhost_net) { 55 uint64_t features = vhost_net_get_acked_features(s->vhost_net); 56 if (features) { 57 s->acked_features = features; 58 } 59 } 60 } 61 62 static void vhost_user_stop(int queues, NetClientState *ncs[]) 63 { 64 int i; 65 NetVhostUserState *s; 66 67 for (i = 0; i < queues; i++) { 68 assert(ncs[i]->info->type == NET_CLIENT_DRIVER_VHOST_USER); 69 70 s = DO_UPCAST(NetVhostUserState, nc, ncs[i]); 71 72 if (s->vhost_net) { 73 vhost_user_save_acked_features(ncs[i]); 74 vhost_net_cleanup(s->vhost_net); 75 } 76 } 77 } 78 79 static int vhost_user_start(int queues, NetClientState *ncs[], 80 VhostUserState *be) 81 { 82 VhostNetOptions options; 83 struct vhost_net *net = NULL; 84 NetVhostUserState *s; 85 int max_queues; 86 int i; 87 88 options.backend_type = VHOST_BACKEND_TYPE_USER; 89 90 for (i = 0; i < queues; i++) { 91 assert(ncs[i]->info->type == NET_CLIENT_DRIVER_VHOST_USER); 92 93 s = DO_UPCAST(NetVhostUserState, nc, ncs[i]); 94 95 options.net_backend = ncs[i]; 96 options.opaque = be; 97 options.busyloop_timeout = 0; 98 options.nvqs = 2; 99 net = vhost_net_init(&options); 100 if (!net) { 101 error_report("failed to init vhost_net for queue %d", i); 102 goto err; 103 } 104 105 if (i == 0) { 106 max_queues = vhost_net_get_max_queues(net); 107 if (queues > max_queues) { 108 error_report("you are asking more queues than supported: %d", 109 max_queues); 110 goto err; 111 } 112 } 113 114 if (s->vhost_net) { 115 vhost_net_cleanup(s->vhost_net); 116 g_free(s->vhost_net); 117 } 118 s->vhost_net = net; 119 } 120 121 return 0; 122 123 err: 124 if (net) { 125 vhost_net_cleanup(net); 126 g_free(net); 127 } 128 vhost_user_stop(i, ncs); 129 return -1; 130 } 131 132 static ssize_t vhost_user_receive(NetClientState *nc, const uint8_t *buf, 133 size_t size) 134 { 135 /* In case of RARP (message size is 60) notify backup to send a fake RARP. 136 This fake RARP will be sent by backend only for guest 137 without GUEST_ANNOUNCE capability. 138 */ 139 if (size == 60) { 140 NetVhostUserState *s = DO_UPCAST(NetVhostUserState, nc, nc); 141 int r; 142 static int display_rarp_failure = 1; 143 char mac_addr[6]; 144 145 /* extract guest mac address from the RARP message */ 146 memcpy(mac_addr, &buf[6], 6); 147 148 r = vhost_net_notify_migration_done(s->vhost_net, mac_addr); 149 150 if ((r != 0) && (display_rarp_failure)) { 151 fprintf(stderr, 152 "Vhost user backend fails to broadcast fake RARP\n"); 153 fflush(stderr); 154 display_rarp_failure = 0; 155 } 156 } 157 158 return size; 159 } 160 161 static void net_vhost_user_cleanup(NetClientState *nc) 162 { 163 NetVhostUserState *s = DO_UPCAST(NetVhostUserState, nc, nc); 164 165 if (s->vhost_net) { 166 vhost_net_cleanup(s->vhost_net); 167 g_free(s->vhost_net); 168 s->vhost_net = NULL; 169 } 170 if (nc->queue_index == 0) { 171 if (s->watch) { 172 g_source_remove(s->watch); 173 s->watch = 0; 174 } 175 qemu_chr_fe_deinit(&s->chr, true); 176 if (s->vhost_user) { 177 vhost_user_cleanup(s->vhost_user); 178 g_free(s->vhost_user); 179 s->vhost_user = NULL; 180 } 181 } 182 183 qemu_purge_queued_packets(nc); 184 } 185 186 static int vhost_user_set_vnet_endianness(NetClientState *nc, 187 bool enable) 188 { 189 /* Nothing to do. If the server supports 190 * VHOST_USER_PROTOCOL_F_CROSS_ENDIAN, it will get the 191 * vnet header endianness from there. If it doesn't, negotiation 192 * fails. 193 */ 194 return 0; 195 } 196 197 static bool vhost_user_has_vnet_hdr(NetClientState *nc) 198 { 199 assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER); 200 201 return true; 202 } 203 204 static bool vhost_user_has_ufo(NetClientState *nc) 205 { 206 assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER); 207 208 return true; 209 } 210 211 static bool vhost_user_check_peer_type(NetClientState *nc, ObjectClass *oc, 212 Error **errp) 213 { 214 const char *driver = object_class_get_name(oc); 215 216 if (!g_str_has_prefix(driver, "virtio-net-")) { 217 error_setg(errp, "vhost-user requires frontend driver virtio-net-*"); 218 return false; 219 } 220 221 return true; 222 } 223 224 static NetClientInfo net_vhost_user_info = { 225 .type = NET_CLIENT_DRIVER_VHOST_USER, 226 .size = sizeof(NetVhostUserState), 227 .receive = vhost_user_receive, 228 .cleanup = net_vhost_user_cleanup, 229 .has_vnet_hdr = vhost_user_has_vnet_hdr, 230 .has_ufo = vhost_user_has_ufo, 231 .set_vnet_be = vhost_user_set_vnet_endianness, 232 .set_vnet_le = vhost_user_set_vnet_endianness, 233 .check_peer_type = vhost_user_check_peer_type, 234 }; 235 236 static gboolean net_vhost_user_watch(void *do_not_use, GIOCondition cond, 237 void *opaque) 238 { 239 NetVhostUserState *s = opaque; 240 241 qemu_chr_fe_disconnect(&s->chr); 242 243 return G_SOURCE_CONTINUE; 244 } 245 246 static void net_vhost_user_event(void *opaque, QEMUChrEvent event); 247 248 static void chr_closed_bh(void *opaque) 249 { 250 const char *name = opaque; 251 NetClientState *ncs[MAX_QUEUE_NUM]; 252 NetVhostUserState *s; 253 Error *err = NULL; 254 int queues, i; 255 256 queues = qemu_find_net_clients_except(name, ncs, 257 NET_CLIENT_DRIVER_NIC, 258 MAX_QUEUE_NUM); 259 assert(queues < MAX_QUEUE_NUM); 260 261 s = DO_UPCAST(NetVhostUserState, nc, ncs[0]); 262 263 for (i = queues -1; i >= 0; i--) { 264 vhost_user_save_acked_features(ncs[i]); 265 } 266 267 qmp_set_link(name, false, &err); 268 269 qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, net_vhost_user_event, 270 NULL, opaque, NULL, true); 271 272 if (err) { 273 error_report_err(err); 274 } 275 qapi_event_send_netdev_vhost_user_disconnected(name); 276 } 277 278 static void net_vhost_user_event(void *opaque, QEMUChrEvent event) 279 { 280 const char *name = opaque; 281 NetClientState *ncs[MAX_QUEUE_NUM]; 282 NetVhostUserState *s; 283 Chardev *chr; 284 Error *err = NULL; 285 int queues; 286 287 queues = qemu_find_net_clients_except(name, ncs, 288 NET_CLIENT_DRIVER_NIC, 289 MAX_QUEUE_NUM); 290 assert(queues < MAX_QUEUE_NUM); 291 292 s = DO_UPCAST(NetVhostUserState, nc, ncs[0]); 293 chr = qemu_chr_fe_get_driver(&s->chr); 294 trace_vhost_user_event(chr->label, event); 295 switch (event) { 296 case CHR_EVENT_OPENED: 297 if (vhost_user_start(queues, ncs, s->vhost_user) < 0) { 298 qemu_chr_fe_disconnect(&s->chr); 299 return; 300 } 301 s->watch = qemu_chr_fe_add_watch(&s->chr, G_IO_HUP, 302 net_vhost_user_watch, s); 303 qmp_set_link(name, true, &err); 304 s->started = true; 305 qapi_event_send_netdev_vhost_user_connected(name, chr->label); 306 break; 307 case CHR_EVENT_CLOSED: 308 /* a close event may happen during a read/write, but vhost 309 * code assumes the vhost_dev remains setup, so delay the 310 * stop & clear to idle. 311 * FIXME: better handle failure in vhost code, remove bh 312 */ 313 if (s->watch) { 314 AioContext *ctx = qemu_get_current_aio_context(); 315 316 g_source_remove(s->watch); 317 s->watch = 0; 318 qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, NULL, NULL, 319 NULL, NULL, false); 320 321 aio_bh_schedule_oneshot(ctx, chr_closed_bh, opaque); 322 } 323 break; 324 case CHR_EVENT_BREAK: 325 case CHR_EVENT_MUX_IN: 326 case CHR_EVENT_MUX_OUT: 327 /* Ignore */ 328 break; 329 } 330 331 if (err) { 332 error_report_err(err); 333 } 334 } 335 336 static int net_vhost_user_init(NetClientState *peer, const char *device, 337 const char *name, Chardev *chr, 338 int queues) 339 { 340 Error *err = NULL; 341 NetClientState *nc, *nc0 = NULL; 342 NetVhostUserState *s = NULL; 343 VhostUserState *user; 344 int i; 345 346 assert(name); 347 assert(queues > 0); 348 349 user = g_new0(struct VhostUserState, 1); 350 for (i = 0; i < queues; i++) { 351 nc = qemu_new_net_client(&net_vhost_user_info, peer, device, name); 352 qemu_set_info_str(nc, "vhost-user%d to %s", i, chr->label); 353 nc->queue_index = i; 354 if (!nc0) { 355 nc0 = nc; 356 s = DO_UPCAST(NetVhostUserState, nc, nc); 357 if (!qemu_chr_fe_init(&s->chr, chr, &err) || 358 !vhost_user_init(user, &s->chr, &err)) { 359 error_report_err(err); 360 goto err; 361 } 362 } 363 s = DO_UPCAST(NetVhostUserState, nc, nc); 364 s->vhost_user = user; 365 } 366 367 s = DO_UPCAST(NetVhostUserState, nc, nc0); 368 do { 369 if (qemu_chr_fe_wait_connected(&s->chr, &err) < 0) { 370 error_report_err(err); 371 goto err; 372 } 373 qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, 374 net_vhost_user_event, NULL, nc0->name, NULL, 375 true); 376 } while (!s->started); 377 378 assert(s->vhost_net); 379 380 return 0; 381 382 err: 383 if (user) { 384 vhost_user_cleanup(user); 385 g_free(user); 386 if (s) { 387 s->vhost_user = NULL; 388 } 389 } 390 if (nc0) { 391 qemu_del_net_client(nc0); 392 } 393 394 return -1; 395 } 396 397 static Chardev *net_vhost_claim_chardev( 398 const NetdevVhostUserOptions *opts, Error **errp) 399 { 400 Chardev *chr = qemu_chr_find(opts->chardev); 401 402 if (chr == NULL) { 403 error_setg(errp, "chardev \"%s\" not found", opts->chardev); 404 return NULL; 405 } 406 407 if (!qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_RECONNECTABLE)) { 408 error_setg(errp, "chardev \"%s\" is not reconnectable", 409 opts->chardev); 410 return NULL; 411 } 412 if (!qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_FD_PASS)) { 413 error_setg(errp, "chardev \"%s\" does not support FD passing", 414 opts->chardev); 415 return NULL; 416 } 417 418 return chr; 419 } 420 421 int net_init_vhost_user(const Netdev *netdev, const char *name, 422 NetClientState *peer, Error **errp) 423 { 424 int queues; 425 const NetdevVhostUserOptions *vhost_user_opts; 426 Chardev *chr; 427 428 assert(netdev->type == NET_CLIENT_DRIVER_VHOST_USER); 429 vhost_user_opts = &netdev->u.vhost_user; 430 431 chr = net_vhost_claim_chardev(vhost_user_opts, errp); 432 if (!chr) { 433 return -1; 434 } 435 436 queues = vhost_user_opts->has_queues ? vhost_user_opts->queues : 1; 437 if (queues < 1 || queues > MAX_QUEUE_NUM) { 438 error_setg(errp, 439 "vhost-user number of queues must be in range [1, %d]", 440 MAX_QUEUE_NUM); 441 return -1; 442 } 443 444 return net_vhost_user_init(peer, "vhost_user", name, chr, queues); 445 } 446