xref: /openbmc/qemu/hw/net/vhost_net.c (revision c576d8bf)
1 /*
2  * vhost-net support
3  *
4  * Copyright Red Hat, Inc. 2010
5  *
6  * Authors:
7  *  Michael S. Tsirkin <mst@redhat.com>
8  *
9  * This work is licensed under the terms of the GNU GPL, version 2.  See
10  * the COPYING file in the top-level directory.
11  *
12  * Contributions after 2012-01-13 are licensed under the terms of the
13  * GNU GPL, version 2 or (at your option) any later version.
14  */
15 
16 #include "qemu/osdep.h"
17 #include "net/net.h"
18 #include "net/tap.h"
19 #include "net/vhost-user.h"
20 #include "net/vhost-vdpa.h"
21 
22 #include "standard-headers/linux/vhost_types.h"
23 #include "hw/virtio/virtio-net.h"
24 #include "net/vhost_net.h"
25 #include "qapi/error.h"
26 #include "qemu/error-report.h"
27 #include "qemu/main-loop.h"
28 
29 #include <sys/socket.h>
30 #include <net/if.h>
31 #include <netinet/in.h>
32 
33 
34 #include "standard-headers/linux/virtio_ring.h"
35 #include "hw/virtio/vhost.h"
36 #include "hw/virtio/virtio-bus.h"
37 #include "linux-headers/linux/vhost.h"
38 
39 
40 /* Features supported by host kernel. */
41 static const int kernel_feature_bits[] = {
42     VIRTIO_F_NOTIFY_ON_EMPTY,
43     VIRTIO_RING_F_INDIRECT_DESC,
44     VIRTIO_RING_F_EVENT_IDX,
45     VIRTIO_NET_F_MRG_RXBUF,
46     VIRTIO_F_VERSION_1,
47     VIRTIO_NET_F_MTU,
48     VIRTIO_F_IOMMU_PLATFORM,
49     VIRTIO_F_RING_PACKED,
50     VIRTIO_F_RING_RESET,
51     VIRTIO_NET_F_HASH_REPORT,
52     VHOST_INVALID_FEATURE_BIT
53 };
54 
55 /* Features supported by others. */
56 static const int user_feature_bits[] = {
57     VIRTIO_F_NOTIFY_ON_EMPTY,
58     VIRTIO_RING_F_INDIRECT_DESC,
59     VIRTIO_RING_F_EVENT_IDX,
60 
61     VIRTIO_F_ANY_LAYOUT,
62     VIRTIO_F_VERSION_1,
63     VIRTIO_NET_F_CSUM,
64     VIRTIO_NET_F_GUEST_CSUM,
65     VIRTIO_NET_F_GSO,
66     VIRTIO_NET_F_GUEST_TSO4,
67     VIRTIO_NET_F_GUEST_TSO6,
68     VIRTIO_NET_F_GUEST_ECN,
69     VIRTIO_NET_F_GUEST_UFO,
70     VIRTIO_NET_F_HOST_TSO4,
71     VIRTIO_NET_F_HOST_TSO6,
72     VIRTIO_NET_F_HOST_ECN,
73     VIRTIO_NET_F_HOST_UFO,
74     VIRTIO_NET_F_MRG_RXBUF,
75     VIRTIO_NET_F_MTU,
76     VIRTIO_F_IOMMU_PLATFORM,
77     VIRTIO_F_RING_PACKED,
78     VIRTIO_F_RING_RESET,
79     VIRTIO_NET_F_RSS,
80     VIRTIO_NET_F_HASH_REPORT,
81     VIRTIO_NET_F_GUEST_USO4,
82     VIRTIO_NET_F_GUEST_USO6,
83     VIRTIO_NET_F_HOST_USO,
84 
85     /* This bit implies RARP isn't sent by QEMU out of band */
86     VIRTIO_NET_F_GUEST_ANNOUNCE,
87 
88     VIRTIO_NET_F_MQ,
89 
90     VHOST_INVALID_FEATURE_BIT
91 };
92 
93 static const int *vhost_net_get_feature_bits(struct vhost_net *net)
94 {
95     const int *feature_bits = 0;
96 
97     switch (net->nc->info->type) {
98     case NET_CLIENT_DRIVER_TAP:
99         feature_bits = kernel_feature_bits;
100         break;
101     case NET_CLIENT_DRIVER_VHOST_USER:
102         feature_bits = user_feature_bits;
103         break;
104 #ifdef CONFIG_VHOST_NET_VDPA
105     case NET_CLIENT_DRIVER_VHOST_VDPA:
106         feature_bits = vdpa_feature_bits;
107         break;
108 #endif
109     default:
110         error_report("Feature bits not defined for this type: %d",
111                 net->nc->info->type);
112         break;
113     }
114 
115     return feature_bits;
116 }
117 
118 uint64_t vhost_net_get_features(struct vhost_net *net, uint64_t features)
119 {
120     return vhost_get_features(&net->dev, vhost_net_get_feature_bits(net),
121             features);
122 }
123 int vhost_net_get_config(struct vhost_net *net,  uint8_t *config,
124                          uint32_t config_len)
125 {
126     return vhost_dev_get_config(&net->dev, config, config_len, NULL);
127 }
128 int vhost_net_set_config(struct vhost_net *net, const uint8_t *data,
129                          uint32_t offset, uint32_t size, uint32_t flags)
130 {
131     return vhost_dev_set_config(&net->dev, data, offset, size, flags);
132 }
133 
134 void vhost_net_ack_features(struct vhost_net *net, uint64_t features)
135 {
136     net->dev.acked_features = net->dev.backend_features;
137     vhost_ack_features(&net->dev, vhost_net_get_feature_bits(net), features);
138 }
139 
140 uint64_t vhost_net_get_max_queues(VHostNetState *net)
141 {
142     return net->dev.max_queues;
143 }
144 
145 uint64_t vhost_net_get_acked_features(VHostNetState *net)
146 {
147     return net->dev.acked_features;
148 }
149 
150 void vhost_net_save_acked_features(NetClientState *nc)
151 {
152 #ifdef CONFIG_VHOST_NET_USER
153     if (nc->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
154         vhost_user_save_acked_features(nc);
155     }
156 #endif
157 }
158 
159 static int vhost_net_get_fd(NetClientState *backend)
160 {
161     switch (backend->info->type) {
162     case NET_CLIENT_DRIVER_TAP:
163         return tap_get_fd(backend);
164     default:
165         fprintf(stderr, "vhost-net requires tap backend\n");
166         return -ENOSYS;
167     }
168 }
169 
170 struct vhost_net *vhost_net_init(VhostNetOptions *options)
171 {
172     int r;
173     bool backend_kernel = options->backend_type == VHOST_BACKEND_TYPE_KERNEL;
174     struct vhost_net *net = g_new0(struct vhost_net, 1);
175     uint64_t features = 0;
176     Error *local_err = NULL;
177 
178     if (!options->net_backend) {
179         fprintf(stderr, "vhost-net requires net backend to be setup\n");
180         goto fail;
181     }
182     net->nc = options->net_backend;
183     net->dev.nvqs = options->nvqs;
184 
185     net->dev.max_queues = 1;
186     net->dev.vqs = net->vqs;
187 
188     if (backend_kernel) {
189         r = vhost_net_get_fd(options->net_backend);
190         if (r < 0) {
191             goto fail;
192         }
193         net->dev.backend_features = qemu_has_vnet_hdr(options->net_backend)
194             ? 0 : (1ULL << VHOST_NET_F_VIRTIO_NET_HDR);
195         net->backend = r;
196         net->dev.protocol_features = 0;
197     } else {
198         net->dev.backend_features = 0;
199         net->dev.protocol_features = 0;
200         net->backend = -1;
201 
202         /* vhost-user needs vq_index to initiate a specific queue pair */
203         net->dev.vq_index = net->nc->queue_index * net->dev.nvqs;
204     }
205 
206     r = vhost_dev_init(&net->dev, options->opaque,
207                        options->backend_type, options->busyloop_timeout,
208                        &local_err);
209     if (r < 0) {
210         error_report_err(local_err);
211         goto fail;
212     }
213     if (backend_kernel) {
214         if (!qemu_has_vnet_hdr_len(options->net_backend,
215                                sizeof(struct virtio_net_hdr_mrg_rxbuf))) {
216             net->dev.features &= ~(1ULL << VIRTIO_NET_F_MRG_RXBUF);
217         }
218         if (~net->dev.features & net->dev.backend_features) {
219             fprintf(stderr, "vhost lacks feature mask 0x%" PRIx64
220                    " for backend\n",
221                    (uint64_t)(~net->dev.features & net->dev.backend_features));
222             goto fail;
223         }
224     }
225 
226     /* Set sane init value. Override when guest acks. */
227 #ifdef CONFIG_VHOST_NET_USER
228     if (net->nc->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
229         features = vhost_user_get_acked_features(net->nc);
230         if (~net->dev.features & features) {
231             fprintf(stderr, "vhost lacks feature mask 0x%" PRIx64
232                     " for backend\n",
233                     (uint64_t)(~net->dev.features & features));
234             goto fail;
235         }
236     }
237 #endif
238 
239     vhost_net_ack_features(net, features);
240 
241     return net;
242 
243 fail:
244     vhost_dev_cleanup(&net->dev);
245     g_free(net);
246     return NULL;
247 }
248 
249 static void vhost_net_set_vq_index(struct vhost_net *net, int vq_index,
250                                    int vq_index_end)
251 {
252     net->dev.vq_index = vq_index;
253     net->dev.vq_index_end = vq_index_end;
254 }
255 
256 static int vhost_net_start_one(struct vhost_net *net,
257                                VirtIODevice *dev)
258 {
259     struct vhost_vring_file file = { };
260     int r;
261 
262     if (net->nc->info->start) {
263         r = net->nc->info->start(net->nc);
264         if (r < 0) {
265             return r;
266         }
267     }
268 
269     r = vhost_dev_enable_notifiers(&net->dev, dev);
270     if (r < 0) {
271         goto fail_notifiers;
272     }
273 
274     r = vhost_dev_start(&net->dev, dev, false);
275     if (r < 0) {
276         goto fail_start;
277     }
278 
279     if (net->nc->info->poll) {
280         net->nc->info->poll(net->nc, false);
281     }
282 
283     if (net->nc->info->type == NET_CLIENT_DRIVER_TAP) {
284         qemu_set_fd_handler(net->backend, NULL, NULL, NULL);
285         file.fd = net->backend;
286         for (file.index = 0; file.index < net->dev.nvqs; ++file.index) {
287             if (!virtio_queue_enabled(dev, net->dev.vq_index +
288                                       file.index)) {
289                 /* Queue might not be ready for start */
290                 continue;
291             }
292             r = vhost_net_set_backend(&net->dev, &file);
293             if (r < 0) {
294                 r = -errno;
295                 goto fail;
296             }
297         }
298     }
299 
300     if (net->nc->info->load) {
301         r = net->nc->info->load(net->nc);
302         if (r < 0) {
303             goto fail;
304         }
305     }
306     return 0;
307 fail:
308     file.fd = -1;
309     if (net->nc->info->type == NET_CLIENT_DRIVER_TAP) {
310         while (file.index-- > 0) {
311             if (!virtio_queue_enabled(dev, net->dev.vq_index +
312                                       file.index)) {
313                 /* Queue might not be ready for start */
314                 continue;
315             }
316             int r = vhost_net_set_backend(&net->dev, &file);
317             assert(r >= 0);
318         }
319     }
320     if (net->nc->info->poll) {
321         net->nc->info->poll(net->nc, true);
322     }
323     vhost_dev_stop(&net->dev, dev, false);
324 fail_start:
325     vhost_dev_disable_notifiers(&net->dev, dev);
326 fail_notifiers:
327     return r;
328 }
329 
330 static void vhost_net_stop_one(struct vhost_net *net,
331                                VirtIODevice *dev)
332 {
333     struct vhost_vring_file file = { .fd = -1 };
334 
335     if (net->nc->info->type == NET_CLIENT_DRIVER_TAP) {
336         for (file.index = 0; file.index < net->dev.nvqs; ++file.index) {
337             int r = vhost_net_set_backend(&net->dev, &file);
338             assert(r >= 0);
339         }
340     }
341     if (net->nc->info->poll) {
342         net->nc->info->poll(net->nc, true);
343     }
344     vhost_dev_stop(&net->dev, dev, false);
345     if (net->nc->info->stop) {
346         net->nc->info->stop(net->nc);
347     }
348     vhost_dev_disable_notifiers(&net->dev, dev);
349 }
350 
351 int vhost_net_start(VirtIODevice *dev, NetClientState *ncs,
352                     int data_queue_pairs, int cvq)
353 {
354     BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(dev)));
355     VirtioBusState *vbus = VIRTIO_BUS(qbus);
356     VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus);
357     int total_notifiers = data_queue_pairs * 2 + cvq;
358     VirtIONet *n = VIRTIO_NET(dev);
359     int nvhosts = data_queue_pairs + cvq;
360     struct vhost_net *net;
361     int r, e, i, index_end = data_queue_pairs * 2;
362     NetClientState *peer;
363 
364     if (cvq) {
365         index_end += 1;
366     }
367 
368     if (!k->set_guest_notifiers) {
369         error_report("binding does not support guest notifiers");
370         return -ENOSYS;
371     }
372 
373     for (i = 0; i < nvhosts; i++) {
374 
375         if (i < data_queue_pairs) {
376             peer = qemu_get_peer(ncs, i);
377         } else { /* Control Virtqueue */
378             peer = qemu_get_peer(ncs, n->max_queue_pairs);
379         }
380 
381         net = get_vhost_net(peer);
382         vhost_net_set_vq_index(net, i * 2, index_end);
383 
384         /* Suppress the masking guest notifiers on vhost user
385          * because vhost user doesn't interrupt masking/unmasking
386          * properly.
387          */
388         if (net->nc->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
389             dev->use_guest_notifier_mask = false;
390         }
391      }
392 
393     r = k->set_guest_notifiers(qbus->parent, total_notifiers, true);
394     if (r < 0) {
395         error_report("Error binding guest notifier: %d", -r);
396         goto err;
397     }
398 
399     for (i = 0; i < nvhosts; i++) {
400         if (i < data_queue_pairs) {
401             peer = qemu_get_peer(ncs, i);
402         } else {
403             peer = qemu_get_peer(ncs, n->max_queue_pairs);
404         }
405 
406         if (peer->vring_enable) {
407             /* restore vring enable state */
408             r = vhost_set_vring_enable(peer, peer->vring_enable);
409 
410             if (r < 0) {
411                 goto err_start;
412             }
413         }
414 
415         r = vhost_net_start_one(get_vhost_net(peer), dev);
416         if (r < 0) {
417             goto err_start;
418         }
419     }
420 
421     return 0;
422 
423 err_start:
424     while (--i >= 0) {
425         peer = qemu_get_peer(ncs, i < data_queue_pairs ?
426                                   i : n->max_queue_pairs);
427         vhost_net_stop_one(get_vhost_net(peer), dev);
428     }
429     e = k->set_guest_notifiers(qbus->parent, total_notifiers, false);
430     if (e < 0) {
431         fprintf(stderr, "vhost guest notifier cleanup failed: %d\n", e);
432         fflush(stderr);
433     }
434 err:
435     return r;
436 }
437 
438 void vhost_net_stop(VirtIODevice *dev, NetClientState *ncs,
439                     int data_queue_pairs, int cvq)
440 {
441     BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(dev)));
442     VirtioBusState *vbus = VIRTIO_BUS(qbus);
443     VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus);
444     VirtIONet *n = VIRTIO_NET(dev);
445     NetClientState *peer;
446     int total_notifiers = data_queue_pairs * 2 + cvq;
447     int nvhosts = data_queue_pairs + cvq;
448     int i, r;
449 
450     for (i = 0; i < nvhosts; i++) {
451         if (i < data_queue_pairs) {
452             peer = qemu_get_peer(ncs, i);
453         } else {
454             peer = qemu_get_peer(ncs, n->max_queue_pairs);
455         }
456         vhost_net_stop_one(get_vhost_net(peer), dev);
457     }
458 
459     r = k->set_guest_notifiers(qbus->parent, total_notifiers, false);
460     if (r < 0) {
461         fprintf(stderr, "vhost guest notifier cleanup failed: %d\n", r);
462         fflush(stderr);
463     }
464     assert(r >= 0);
465 }
466 
467 void vhost_net_cleanup(struct vhost_net *net)
468 {
469     vhost_dev_cleanup(&net->dev);
470 }
471 
472 int vhost_net_notify_migration_done(struct vhost_net *net, char* mac_addr)
473 {
474     const VhostOps *vhost_ops = net->dev.vhost_ops;
475 
476     assert(vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
477     assert(vhost_ops->vhost_migration_done);
478 
479     return vhost_ops->vhost_migration_done(&net->dev, mac_addr);
480 }
481 
482 bool vhost_net_virtqueue_pending(VHostNetState *net, int idx)
483 {
484     return vhost_virtqueue_pending(&net->dev, idx);
485 }
486 
487 void vhost_net_virtqueue_mask(VHostNetState *net, VirtIODevice *dev,
488                               int idx, bool mask)
489 {
490     vhost_virtqueue_mask(&net->dev, dev, idx, mask);
491 }
492 
493 bool vhost_net_config_pending(VHostNetState *net)
494 {
495     return vhost_config_pending(&net->dev);
496 }
497 
498 void vhost_net_config_mask(VHostNetState *net, VirtIODevice *dev, bool mask)
499 {
500     vhost_config_mask(&net->dev, dev, mask);
501 }
502 VHostNetState *get_vhost_net(NetClientState *nc)
503 {
504     VHostNetState *vhost_net = 0;
505 
506     if (!nc) {
507         return 0;
508     }
509 
510     switch (nc->info->type) {
511     case NET_CLIENT_DRIVER_TAP:
512         vhost_net = tap_get_vhost_net(nc);
513         /*
514          * tap_get_vhost_net() can return NULL if a tap net-device backend is
515          * created with 'vhost=off' option, 'vhostforce=off' or no vhost or
516          * vhostforce or vhostfd options at all. Please see net_init_tap_one().
517          * Hence, we omit the assertion here.
518          */
519         break;
520 #ifdef CONFIG_VHOST_NET_USER
521     case NET_CLIENT_DRIVER_VHOST_USER:
522         vhost_net = vhost_user_get_vhost_net(nc);
523         assert(vhost_net);
524         break;
525 #endif
526 #ifdef CONFIG_VHOST_NET_VDPA
527     case NET_CLIENT_DRIVER_VHOST_VDPA:
528         vhost_net = vhost_vdpa_get_vhost_net(nc);
529         assert(vhost_net);
530         break;
531 #endif
532     default:
533         break;
534     }
535 
536     return vhost_net;
537 }
538 
539 int vhost_set_vring_enable(NetClientState *nc, int enable)
540 {
541     VHostNetState *net = get_vhost_net(nc);
542     const VhostOps *vhost_ops = net->dev.vhost_ops;
543 
544     nc->vring_enable = enable;
545 
546     if (vhost_ops && vhost_ops->vhost_set_vring_enable) {
547         return vhost_ops->vhost_set_vring_enable(&net->dev, enable);
548     }
549 
550     return 0;
551 }
552 
553 int vhost_net_set_mtu(struct vhost_net *net, uint16_t mtu)
554 {
555     const VhostOps *vhost_ops = net->dev.vhost_ops;
556 
557     if (!vhost_ops->vhost_net_set_mtu) {
558         return 0;
559     }
560 
561     return vhost_ops->vhost_net_set_mtu(&net->dev, mtu);
562 }
563 
564 void vhost_net_virtqueue_reset(VirtIODevice *vdev, NetClientState *nc,
565                                int vq_index)
566 {
567     VHostNetState *net = get_vhost_net(nc->peer);
568     const VhostOps *vhost_ops = net->dev.vhost_ops;
569     struct vhost_vring_file file = { .fd = -1 };
570     int idx;
571 
572     /* should only be called after backend is connected */
573     assert(vhost_ops);
574 
575     idx = vhost_ops->vhost_get_vq_index(&net->dev, vq_index);
576 
577     if (net->nc->info->type == NET_CLIENT_DRIVER_TAP) {
578         file.index = idx;
579         int r = vhost_net_set_backend(&net->dev, &file);
580         assert(r >= 0);
581     }
582 
583     vhost_virtqueue_stop(&net->dev,
584                          vdev,
585                          net->dev.vqs + idx,
586                          net->dev.vq_index + idx);
587 }
588 
589 int vhost_net_virtqueue_restart(VirtIODevice *vdev, NetClientState *nc,
590                                 int vq_index)
591 {
592     VHostNetState *net = get_vhost_net(nc->peer);
593     const VhostOps *vhost_ops = net->dev.vhost_ops;
594     struct vhost_vring_file file = { };
595     int idx, r;
596 
597     if (!net->dev.started) {
598         return -EBUSY;
599     }
600 
601     /* should only be called after backend is connected */
602     assert(vhost_ops);
603 
604     idx = vhost_ops->vhost_get_vq_index(&net->dev, vq_index);
605 
606     r = vhost_virtqueue_start(&net->dev,
607                               vdev,
608                               net->dev.vqs + idx,
609                               net->dev.vq_index + idx);
610     if (r < 0) {
611         goto err_start;
612     }
613 
614     if (net->nc->info->type == NET_CLIENT_DRIVER_TAP) {
615         file.index = idx;
616         file.fd = net->backend;
617         r = vhost_net_set_backend(&net->dev, &file);
618         if (r < 0) {
619             r = -errno;
620             goto err_start;
621         }
622     }
623 
624     return 0;
625 
626 err_start:
627     error_report("Error when restarting the queue.");
628 
629     if (net->nc->info->type == NET_CLIENT_DRIVER_TAP) {
630         file.fd = VHOST_FILE_UNBIND;
631         file.index = idx;
632         int r = vhost_net_set_backend(&net->dev, &file);
633         assert(r >= 0);
634     }
635 
636     vhost_dev_stop(&net->dev, vdev, false);
637 
638     return r;
639 }
640