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 int vhost_user_set_vnet_endianness(NetClientState *nc, 176 bool enable) 177 { 178 /* Nothing to do. If the server supports 179 * VHOST_USER_PROTOCOL_F_CROSS_ENDIAN, it will get the 180 * vnet header endianness from there. If it doesn't, negotiation 181 * fails. 182 */ 183 return 0; 184 } 185 186 static bool vhost_user_has_vnet_hdr(NetClientState *nc) 187 { 188 assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER); 189 190 return true; 191 } 192 193 static bool vhost_user_has_ufo(NetClientState *nc) 194 { 195 assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER); 196 197 return true; 198 } 199 200 static NetClientInfo net_vhost_user_info = { 201 .type = NET_CLIENT_DRIVER_VHOST_USER, 202 .size = sizeof(NetVhostUserState), 203 .receive = vhost_user_receive, 204 .cleanup = net_vhost_user_cleanup, 205 .has_vnet_hdr = vhost_user_has_vnet_hdr, 206 .has_ufo = vhost_user_has_ufo, 207 .set_vnet_be = vhost_user_set_vnet_endianness, 208 .set_vnet_le = vhost_user_set_vnet_endianness, 209 }; 210 211 static gboolean net_vhost_user_watch(void *do_not_use, GIOCondition cond, 212 void *opaque) 213 { 214 NetVhostUserState *s = opaque; 215 216 qemu_chr_fe_disconnect(&s->chr); 217 218 return TRUE; 219 } 220 221 static void net_vhost_user_event(void *opaque, QEMUChrEvent event); 222 223 static void chr_closed_bh(void *opaque) 224 { 225 const char *name = opaque; 226 NetClientState *ncs[MAX_QUEUE_NUM]; 227 NetVhostUserState *s; 228 Error *err = NULL; 229 int queues, i; 230 231 queues = qemu_find_net_clients_except(name, ncs, 232 NET_CLIENT_DRIVER_NIC, 233 MAX_QUEUE_NUM); 234 assert(queues < MAX_QUEUE_NUM); 235 236 s = DO_UPCAST(NetVhostUserState, nc, ncs[0]); 237 238 for (i = queues -1; i >= 0; i--) { 239 s = DO_UPCAST(NetVhostUserState, nc, ncs[i]); 240 241 if (s->vhost_net) { 242 s->acked_features = vhost_net_get_acked_features(s->vhost_net); 243 } 244 } 245 246 qmp_set_link(name, false, &err); 247 248 qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, net_vhost_user_event, 249 NULL, opaque, NULL, true); 250 251 if (err) { 252 error_report_err(err); 253 } 254 } 255 256 static void net_vhost_user_event(void *opaque, QEMUChrEvent event) 257 { 258 const char *name = opaque; 259 NetClientState *ncs[MAX_QUEUE_NUM]; 260 NetVhostUserState *s; 261 Chardev *chr; 262 Error *err = NULL; 263 int queues; 264 265 queues = qemu_find_net_clients_except(name, ncs, 266 NET_CLIENT_DRIVER_NIC, 267 MAX_QUEUE_NUM); 268 assert(queues < MAX_QUEUE_NUM); 269 270 s = DO_UPCAST(NetVhostUserState, nc, ncs[0]); 271 chr = qemu_chr_fe_get_driver(&s->chr); 272 trace_vhost_user_event(chr->label, event); 273 switch (event) { 274 case CHR_EVENT_OPENED: 275 if (vhost_user_start(queues, ncs, s->vhost_user) < 0) { 276 qemu_chr_fe_disconnect(&s->chr); 277 return; 278 } 279 s->watch = qemu_chr_fe_add_watch(&s->chr, G_IO_HUP, 280 net_vhost_user_watch, s); 281 qmp_set_link(name, true, &err); 282 s->started = true; 283 break; 284 case CHR_EVENT_CLOSED: 285 /* a close event may happen during a read/write, but vhost 286 * code assumes the vhost_dev remains setup, so delay the 287 * stop & clear to idle. 288 * FIXME: better handle failure in vhost code, remove bh 289 */ 290 if (s->watch) { 291 AioContext *ctx = qemu_get_current_aio_context(); 292 293 g_source_remove(s->watch); 294 s->watch = 0; 295 qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, NULL, NULL, 296 NULL, NULL, false); 297 298 aio_bh_schedule_oneshot(ctx, chr_closed_bh, opaque); 299 } 300 break; 301 case CHR_EVENT_BREAK: 302 case CHR_EVENT_MUX_IN: 303 case CHR_EVENT_MUX_OUT: 304 /* Ignore */ 305 break; 306 } 307 308 if (err) { 309 error_report_err(err); 310 } 311 } 312 313 static int net_vhost_user_init(NetClientState *peer, const char *device, 314 const char *name, Chardev *chr, 315 int queues) 316 { 317 Error *err = NULL; 318 NetClientState *nc, *nc0 = NULL; 319 NetVhostUserState *s = NULL; 320 VhostUserState *user; 321 int i; 322 323 assert(name); 324 assert(queues > 0); 325 326 user = g_new0(struct VhostUserState, 1); 327 for (i = 0; i < queues; i++) { 328 nc = qemu_new_net_client(&net_vhost_user_info, peer, device, name); 329 snprintf(nc->info_str, sizeof(nc->info_str), "vhost-user%d to %s", 330 i, chr->label); 331 nc->queue_index = i; 332 if (!nc0) { 333 nc0 = nc; 334 s = DO_UPCAST(NetVhostUserState, nc, nc); 335 if (!qemu_chr_fe_init(&s->chr, chr, &err) || 336 !vhost_user_init(user, &s->chr, &err)) { 337 error_report_err(err); 338 goto err; 339 } 340 } 341 s = DO_UPCAST(NetVhostUserState, nc, nc); 342 s->vhost_user = user; 343 } 344 345 s = DO_UPCAST(NetVhostUserState, nc, nc0); 346 do { 347 if (qemu_chr_fe_wait_connected(&s->chr, &err) < 0) { 348 error_report_err(err); 349 goto err; 350 } 351 qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, 352 net_vhost_user_event, NULL, nc0->name, NULL, 353 true); 354 } while (!s->started); 355 356 assert(s->vhost_net); 357 358 return 0; 359 360 err: 361 if (user) { 362 vhost_user_cleanup(user); 363 g_free(user); 364 if (s) { 365 s->vhost_user = NULL; 366 } 367 } 368 if (nc0) { 369 qemu_del_net_client(nc0); 370 } 371 372 return -1; 373 } 374 375 static Chardev *net_vhost_claim_chardev( 376 const NetdevVhostUserOptions *opts, Error **errp) 377 { 378 Chardev *chr = qemu_chr_find(opts->chardev); 379 380 if (chr == NULL) { 381 error_setg(errp, "chardev \"%s\" not found", opts->chardev); 382 return NULL; 383 } 384 385 if (!qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_RECONNECTABLE)) { 386 error_setg(errp, "chardev \"%s\" is not reconnectable", 387 opts->chardev); 388 return NULL; 389 } 390 if (!qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_FD_PASS)) { 391 error_setg(errp, "chardev \"%s\" does not support FD passing", 392 opts->chardev); 393 return NULL; 394 } 395 396 return chr; 397 } 398 399 static int net_vhost_check_net(void *opaque, QemuOpts *opts, Error **errp) 400 { 401 const char *name = opaque; 402 const char *driver, *netdev; 403 404 driver = qemu_opt_get(opts, "driver"); 405 netdev = qemu_opt_get(opts, "netdev"); 406 407 if (!driver || !netdev) { 408 return 0; 409 } 410 411 if (strcmp(netdev, name) == 0 && 412 !g_str_has_prefix(driver, "virtio-net-")) { 413 error_setg(errp, "vhost-user requires frontend driver virtio-net-*"); 414 return -1; 415 } 416 417 return 0; 418 } 419 420 int net_init_vhost_user(const Netdev *netdev, const char *name, 421 NetClientState *peer, Error **errp) 422 { 423 int queues; 424 const NetdevVhostUserOptions *vhost_user_opts; 425 Chardev *chr; 426 427 assert(netdev->type == NET_CLIENT_DRIVER_VHOST_USER); 428 vhost_user_opts = &netdev->u.vhost_user; 429 430 chr = net_vhost_claim_chardev(vhost_user_opts, errp); 431 if (!chr) { 432 return -1; 433 } 434 435 /* verify net frontend */ 436 if (qemu_opts_foreach(qemu_find_opts("device"), net_vhost_check_net, 437 (char *)name, errp)) { 438 return -1; 439 } 440 441 queues = vhost_user_opts->has_queues ? vhost_user_opts->queues : 1; 442 if (queues < 1 || queues > MAX_QUEUE_NUM) { 443 error_setg(errp, 444 "vhost-user number of queues must be in range [1, %d]", 445 MAX_QUEUE_NUM); 446 return -1; 447 } 448 449 return net_vhost_user_init(peer, "vhost_user", name, chr, queues); 450 } 451