Merge remote-tracking branch 'remotes/bonzini-gitlab/tags/for-upstream' into staging
[qemu.git] / net / vhost-user.c
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(GIOChannel *chan, 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 }