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