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 NetClientInfo net_vhost_user_info = { 202 .type = NET_CLIENT_DRIVER_VHOST_USER, 203 .size = sizeof(NetVhostUserState), 204 .receive = vhost_user_receive, 205 .cleanup = net_vhost_user_cleanup, 206 .has_vnet_hdr = vhost_user_has_vnet_hdr, 207 .has_ufo = vhost_user_has_ufo, 208 .set_vnet_be = vhost_user_set_vnet_endianness, 209 .set_vnet_le = vhost_user_set_vnet_endianness, 210 }; 211 212 static gboolean net_vhost_user_watch(void *do_not_use, GIOCondition cond, 213 void *opaque) 214 { 215 NetVhostUserState *s = opaque; 216 217 qemu_chr_fe_disconnect(&s->chr); 218 219 return TRUE; 220 } 221 222 static void net_vhost_user_event(void *opaque, QEMUChrEvent event); 223 224 static void chr_closed_bh(void *opaque) 225 { 226 const char *name = opaque; 227 NetClientState *ncs[MAX_QUEUE_NUM]; 228 NetVhostUserState *s; 229 Error *err = NULL; 230 int queues, i; 231 232 queues = qemu_find_net_clients_except(name, ncs, 233 NET_CLIENT_DRIVER_NIC, 234 MAX_QUEUE_NUM); 235 assert(queues < MAX_QUEUE_NUM); 236 237 s = DO_UPCAST(NetVhostUserState, nc, ncs[0]); 238 239 for (i = queues -1; i >= 0; i--) { 240 s = DO_UPCAST(NetVhostUserState, nc, ncs[i]); 241 242 if (s->vhost_net) { 243 s->acked_features = vhost_net_get_acked_features(s->vhost_net); 244 } 245 } 246 247 qmp_set_link(name, false, &err); 248 249 qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, net_vhost_user_event, 250 NULL, opaque, NULL, true); 251 252 if (err) { 253 error_report_err(err); 254 } 255 } 256 257 static void net_vhost_user_event(void *opaque, QEMUChrEvent event) 258 { 259 const char *name = opaque; 260 NetClientState *ncs[MAX_QUEUE_NUM]; 261 NetVhostUserState *s; 262 Chardev *chr; 263 Error *err = NULL; 264 int queues; 265 266 queues = qemu_find_net_clients_except(name, ncs, 267 NET_CLIENT_DRIVER_NIC, 268 MAX_QUEUE_NUM); 269 assert(queues < MAX_QUEUE_NUM); 270 271 s = DO_UPCAST(NetVhostUserState, nc, ncs[0]); 272 chr = qemu_chr_fe_get_driver(&s->chr); 273 trace_vhost_user_event(chr->label, event); 274 switch (event) { 275 case CHR_EVENT_OPENED: 276 if (vhost_user_start(queues, ncs, s->vhost_user) < 0) { 277 qemu_chr_fe_disconnect(&s->chr); 278 return; 279 } 280 s->watch = qemu_chr_fe_add_watch(&s->chr, G_IO_HUP, 281 net_vhost_user_watch, s); 282 qmp_set_link(name, true, &err); 283 s->started = true; 284 break; 285 case CHR_EVENT_CLOSED: 286 /* a close event may happen during a read/write, but vhost 287 * code assumes the vhost_dev remains setup, so delay the 288 * stop & clear to idle. 289 * FIXME: better handle failure in vhost code, remove bh 290 */ 291 if (s->watch) { 292 AioContext *ctx = qemu_get_current_aio_context(); 293 294 g_source_remove(s->watch); 295 s->watch = 0; 296 qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, NULL, NULL, 297 NULL, NULL, false); 298 299 aio_bh_schedule_oneshot(ctx, chr_closed_bh, opaque); 300 } 301 break; 302 case CHR_EVENT_BREAK: 303 case CHR_EVENT_MUX_IN: 304 case CHR_EVENT_MUX_OUT: 305 /* Ignore */ 306 break; 307 } 308 309 if (err) { 310 error_report_err(err); 311 } 312 } 313 314 static int net_vhost_user_init(NetClientState *peer, const char *device, 315 const char *name, Chardev *chr, 316 int queues) 317 { 318 Error *err = NULL; 319 NetClientState *nc, *nc0 = NULL; 320 NetVhostUserState *s = NULL; 321 VhostUserState *user; 322 int i; 323 324 assert(name); 325 assert(queues > 0); 326 327 user = g_new0(struct VhostUserState, 1); 328 for (i = 0; i < queues; i++) { 329 nc = qemu_new_net_client(&net_vhost_user_info, peer, device, name); 330 snprintf(nc->info_str, sizeof(nc->info_str), "vhost-user%d to %s", 331 i, chr->label); 332 nc->queue_index = i; 333 if (!nc0) { 334 nc0 = nc; 335 s = DO_UPCAST(NetVhostUserState, nc, nc); 336 if (!qemu_chr_fe_init(&s->chr, chr, &err) || 337 !vhost_user_init(user, &s->chr, &err)) { 338 error_report_err(err); 339 goto err; 340 } 341 } 342 s = DO_UPCAST(NetVhostUserState, nc, nc); 343 s->vhost_user = user; 344 } 345 346 s = DO_UPCAST(NetVhostUserState, nc, nc0); 347 do { 348 if (qemu_chr_fe_wait_connected(&s->chr, &err) < 0) { 349 error_report_err(err); 350 goto err; 351 } 352 qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, 353 net_vhost_user_event, NULL, nc0->name, NULL, 354 true); 355 } while (!s->started); 356 357 assert(s->vhost_net); 358 359 return 0; 360 361 err: 362 if (user) { 363 vhost_user_cleanup(user); 364 g_free(user); 365 if (s) { 366 s->vhost_user = NULL; 367 } 368 } 369 if (nc0) { 370 qemu_del_net_client(nc0); 371 } 372 373 return -1; 374 } 375 376 static Chardev *net_vhost_claim_chardev( 377 const NetdevVhostUserOptions *opts, Error **errp) 378 { 379 Chardev *chr = qemu_chr_find(opts->chardev); 380 381 if (chr == NULL) { 382 error_setg(errp, "chardev \"%s\" not found", opts->chardev); 383 return NULL; 384 } 385 386 if (!qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_RECONNECTABLE)) { 387 error_setg(errp, "chardev \"%s\" is not reconnectable", 388 opts->chardev); 389 return NULL; 390 } 391 if (!qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_FD_PASS)) { 392 error_setg(errp, "chardev \"%s\" does not support FD passing", 393 opts->chardev); 394 return NULL; 395 } 396 397 return chr; 398 } 399 400 static int net_vhost_check_net(void *opaque, QemuOpts *opts, Error **errp) 401 { 402 const char *name = opaque; 403 const char *driver, *netdev; 404 405 driver = qemu_opt_get(opts, "driver"); 406 netdev = qemu_opt_get(opts, "netdev"); 407 408 if (!driver || !netdev) { 409 return 0; 410 } 411 412 if (strcmp(netdev, name) == 0 && 413 !g_str_has_prefix(driver, "virtio-net-")) { 414 error_setg(errp, "vhost-user requires frontend driver virtio-net-*"); 415 return -1; 416 } 417 418 return 0; 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 /* verify net frontend */ 437 if (qemu_opts_foreach(qemu_find_opts("device"), net_vhost_check_net, 438 (char *)name, errp)) { 439 return -1; 440 } 441 442 queues = vhost_user_opts->has_queues ? vhost_user_opts->queues : 1; 443 if (queues < 1 || queues > MAX_QUEUE_NUM) { 444 error_setg(errp, 445 "vhost-user number of queues must be in range [1, %d]", 446 MAX_QUEUE_NUM); 447 return -1; 448 } 449 450 return net_vhost_user_init(peer, "vhost_user", name, chr, queues); 451 } 452