1 /* 2 * Hub net client 3 * 4 * Copyright IBM, Corp. 2012 5 * 6 * Authors: 7 * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> 8 * Zhi Yong Wu <wuzhy@linux.vnet.ibm.com> 9 * 10 * This work is licensed under the terms of the GNU LGPL, version 2 or later. 11 * See the COPYING.LIB file in the top-level directory. 12 * 13 */ 14 15 #include "qemu/osdep.h" 16 #include "monitor/monitor.h" 17 #include "net/net.h" 18 #include "clients.h" 19 #include "hub.h" 20 #include "qemu/iov.h" 21 22 /* 23 * A hub broadcasts incoming packets to all its ports except the source port. 24 * Hubs can be used to provide independent network segments, also confusingly 25 * named the QEMU 'vlan' feature. 26 */ 27 28 typedef struct NetHub NetHub; 29 30 typedef struct NetHubPort { 31 NetClientState nc; 32 QLIST_ENTRY(NetHubPort) next; 33 NetHub *hub; 34 int id; 35 } NetHubPort; 36 37 struct NetHub { 38 int id; 39 QLIST_ENTRY(NetHub) next; 40 int num_ports; 41 QLIST_HEAD(, NetHubPort) ports; 42 }; 43 44 static QLIST_HEAD(, NetHub) hubs = QLIST_HEAD_INITIALIZER(&hubs); 45 46 static ssize_t net_hub_receive(NetHub *hub, NetHubPort *source_port, 47 const uint8_t *buf, size_t len) 48 { 49 NetHubPort *port; 50 51 QLIST_FOREACH(port, &hub->ports, next) { 52 if (port == source_port) { 53 continue; 54 } 55 56 qemu_send_packet(&port->nc, buf, len); 57 } 58 return len; 59 } 60 61 static ssize_t net_hub_receive_iov(NetHub *hub, NetHubPort *source_port, 62 const struct iovec *iov, int iovcnt) 63 { 64 NetHubPort *port; 65 ssize_t len = iov_size(iov, iovcnt); 66 67 QLIST_FOREACH(port, &hub->ports, next) { 68 if (port == source_port) { 69 continue; 70 } 71 72 qemu_sendv_packet(&port->nc, iov, iovcnt); 73 } 74 return len; 75 } 76 77 static NetHub *net_hub_new(int id) 78 { 79 NetHub *hub; 80 81 hub = g_malloc(sizeof(*hub)); 82 hub->id = id; 83 hub->num_ports = 0; 84 QLIST_INIT(&hub->ports); 85 86 QLIST_INSERT_HEAD(&hubs, hub, next); 87 88 return hub; 89 } 90 91 static int net_hub_port_can_receive(NetClientState *nc) 92 { 93 NetHubPort *port; 94 NetHubPort *src_port = DO_UPCAST(NetHubPort, nc, nc); 95 NetHub *hub = src_port->hub; 96 97 QLIST_FOREACH(port, &hub->ports, next) { 98 if (port == src_port) { 99 continue; 100 } 101 102 if (qemu_can_send_packet(&port->nc)) { 103 return 1; 104 } 105 } 106 107 return 0; 108 } 109 110 static ssize_t net_hub_port_receive(NetClientState *nc, 111 const uint8_t *buf, size_t len) 112 { 113 NetHubPort *port = DO_UPCAST(NetHubPort, nc, nc); 114 115 return net_hub_receive(port->hub, port, buf, len); 116 } 117 118 static ssize_t net_hub_port_receive_iov(NetClientState *nc, 119 const struct iovec *iov, int iovcnt) 120 { 121 NetHubPort *port = DO_UPCAST(NetHubPort, nc, nc); 122 123 return net_hub_receive_iov(port->hub, port, iov, iovcnt); 124 } 125 126 static void net_hub_port_cleanup(NetClientState *nc) 127 { 128 NetHubPort *port = DO_UPCAST(NetHubPort, nc, nc); 129 130 QLIST_REMOVE(port, next); 131 } 132 133 static NetClientInfo net_hub_port_info = { 134 .type = NET_CLIENT_DRIVER_HUBPORT, 135 .size = sizeof(NetHubPort), 136 .can_receive = net_hub_port_can_receive, 137 .receive = net_hub_port_receive, 138 .receive_iov = net_hub_port_receive_iov, 139 .cleanup = net_hub_port_cleanup, 140 }; 141 142 static NetHubPort *net_hub_port_new(NetHub *hub, const char *name) 143 { 144 NetClientState *nc; 145 NetHubPort *port; 146 int id = hub->num_ports++; 147 char default_name[128]; 148 149 if (!name) { 150 snprintf(default_name, sizeof(default_name), 151 "hub%dport%d", hub->id, id); 152 name = default_name; 153 } 154 155 nc = qemu_new_net_client(&net_hub_port_info, NULL, "hub", name); 156 port = DO_UPCAST(NetHubPort, nc, nc); 157 port->id = id; 158 port->hub = hub; 159 160 QLIST_INSERT_HEAD(&hub->ports, port, next); 161 162 return port; 163 } 164 165 /** 166 * Create a port on a given hub 167 * @name: Net client name or NULL for default name. 168 * 169 * If there is no existing hub with the given id then a new hub is created. 170 */ 171 NetClientState *net_hub_add_port(int hub_id, const char *name) 172 { 173 NetHub *hub; 174 NetHubPort *port; 175 176 QLIST_FOREACH(hub, &hubs, next) { 177 if (hub->id == hub_id) { 178 break; 179 } 180 } 181 182 if (!hub) { 183 hub = net_hub_new(hub_id); 184 } 185 186 port = net_hub_port_new(hub, name); 187 return &port->nc; 188 } 189 190 /** 191 * Find a specific client on a hub 192 */ 193 NetClientState *net_hub_find_client_by_name(int hub_id, const char *name) 194 { 195 NetHub *hub; 196 NetHubPort *port; 197 NetClientState *peer; 198 199 QLIST_FOREACH(hub, &hubs, next) { 200 if (hub->id == hub_id) { 201 QLIST_FOREACH(port, &hub->ports, next) { 202 peer = port->nc.peer; 203 204 if (peer && strcmp(peer->name, name) == 0) { 205 return peer; 206 } 207 } 208 } 209 } 210 return NULL; 211 } 212 213 /** 214 * Find a available port on a hub; otherwise create one new port 215 */ 216 NetClientState *net_hub_port_find(int hub_id) 217 { 218 NetHub *hub; 219 NetHubPort *port; 220 NetClientState *nc; 221 222 QLIST_FOREACH(hub, &hubs, next) { 223 if (hub->id == hub_id) { 224 QLIST_FOREACH(port, &hub->ports, next) { 225 nc = port->nc.peer; 226 if (!nc) { 227 return &(port->nc); 228 } 229 } 230 break; 231 } 232 } 233 234 nc = net_hub_add_port(hub_id, NULL); 235 return nc; 236 } 237 238 /** 239 * Print hub configuration 240 */ 241 void net_hub_info(Monitor *mon) 242 { 243 NetHub *hub; 244 NetHubPort *port; 245 246 QLIST_FOREACH(hub, &hubs, next) { 247 monitor_printf(mon, "hub %d\n", hub->id); 248 QLIST_FOREACH(port, &hub->ports, next) { 249 monitor_printf(mon, " \\ %s", port->nc.name); 250 if (port->nc.peer) { 251 monitor_printf(mon, ": "); 252 print_net_client(mon, port->nc.peer); 253 } else { 254 monitor_printf(mon, "\n"); 255 } 256 } 257 } 258 } 259 260 /** 261 * Get the hub id that a client is connected to 262 * 263 * @id: Pointer for hub id output, may be NULL 264 */ 265 int net_hub_id_for_client(NetClientState *nc, int *id) 266 { 267 NetHubPort *port; 268 269 if (nc->info->type == NET_CLIENT_DRIVER_HUBPORT) { 270 port = DO_UPCAST(NetHubPort, nc, nc); 271 } else if (nc->peer != NULL && nc->peer->info->type == 272 NET_CLIENT_DRIVER_HUBPORT) { 273 port = DO_UPCAST(NetHubPort, nc, nc->peer); 274 } else { 275 return -ENOENT; 276 } 277 278 if (id) { 279 *id = port->hub->id; 280 } 281 return 0; 282 } 283 284 int net_init_hubport(const Netdev *netdev, const char *name, 285 NetClientState *peer, Error **errp) 286 { 287 const NetdevHubPortOptions *hubport; 288 289 assert(netdev->type == NET_CLIENT_DRIVER_HUBPORT); 290 assert(!peer); 291 hubport = &netdev->u.hubport; 292 293 net_hub_add_port(hubport->hubid, name); 294 return 0; 295 } 296 297 /** 298 * Warn if hub configurations are likely wrong 299 */ 300 void net_hub_check_clients(void) 301 { 302 NetHub *hub; 303 NetHubPort *port; 304 NetClientState *peer; 305 306 QLIST_FOREACH(hub, &hubs, next) { 307 int has_nic = 0, has_host_dev = 0; 308 309 QLIST_FOREACH(port, &hub->ports, next) { 310 peer = port->nc.peer; 311 if (!peer) { 312 fprintf(stderr, "Warning: hub port %s has no peer\n", 313 port->nc.name); 314 continue; 315 } 316 317 switch (peer->info->type) { 318 case NET_CLIENT_DRIVER_NIC: 319 has_nic = 1; 320 break; 321 case NET_CLIENT_DRIVER_USER: 322 case NET_CLIENT_DRIVER_TAP: 323 case NET_CLIENT_DRIVER_SOCKET: 324 case NET_CLIENT_DRIVER_VDE: 325 case NET_CLIENT_DRIVER_VHOST_USER: 326 has_host_dev = 1; 327 break; 328 default: 329 break; 330 } 331 } 332 if (has_host_dev && !has_nic) { 333 fprintf(stderr, "Warning: vlan %d with no nics\n", hub->id); 334 } 335 if (has_nic && !has_host_dev) { 336 fprintf(stderr, 337 "Warning: vlan %d is not connected to host network\n", 338 hub->id); 339 } 340 } 341 } 342 343 bool net_hub_flush(NetClientState *nc) 344 { 345 NetHubPort *port; 346 NetHubPort *source_port = DO_UPCAST(NetHubPort, nc, nc); 347 int ret = 0; 348 349 QLIST_FOREACH(port, &source_port->hub->ports, next) { 350 if (port != source_port) { 351 ret += qemu_net_queue_flush(port->nc.incoming_queue); 352 } 353 } 354 return ret ? true : false; 355 } 356