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