xref: /openbmc/qemu/hw/net/vhost_net.c (revision c00506aa)
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 "qemu/error-report.h"
26 #include "qemu/main-loop.h"
27 
28 #include <sys/socket.h>
29 #include <net/if.h>
30 #include <netinet/in.h>
31 
32 
33 #include "standard-headers/linux/virtio_ring.h"
34 #include "hw/virtio/vhost.h"
35 #include "hw/virtio/virtio-bus.h"
36 
37 
38 /* Features supported by host kernel. */
39 static const int kernel_feature_bits[] = {
40     VIRTIO_F_NOTIFY_ON_EMPTY,
41     VIRTIO_RING_F_INDIRECT_DESC,
42     VIRTIO_RING_F_EVENT_IDX,
43     VIRTIO_NET_F_MRG_RXBUF,
44     VIRTIO_F_VERSION_1,
45     VIRTIO_NET_F_MTU,
46     VIRTIO_F_IOMMU_PLATFORM,
47     VIRTIO_F_RING_PACKED,
48     VHOST_INVALID_FEATURE_BIT
49 };
50 
51 /* Features supported by others. */
52 static const int user_feature_bits[] = {
53     VIRTIO_F_NOTIFY_ON_EMPTY,
54     VIRTIO_RING_F_INDIRECT_DESC,
55     VIRTIO_RING_F_EVENT_IDX,
56 
57     VIRTIO_F_ANY_LAYOUT,
58     VIRTIO_F_VERSION_1,
59     VIRTIO_NET_F_CSUM,
60     VIRTIO_NET_F_GUEST_CSUM,
61     VIRTIO_NET_F_GSO,
62     VIRTIO_NET_F_GUEST_TSO4,
63     VIRTIO_NET_F_GUEST_TSO6,
64     VIRTIO_NET_F_GUEST_ECN,
65     VIRTIO_NET_F_GUEST_UFO,
66     VIRTIO_NET_F_HOST_TSO4,
67     VIRTIO_NET_F_HOST_TSO6,
68     VIRTIO_NET_F_HOST_ECN,
69     VIRTIO_NET_F_HOST_UFO,
70     VIRTIO_NET_F_MRG_RXBUF,
71     VIRTIO_NET_F_MTU,
72     VIRTIO_F_IOMMU_PLATFORM,
73     VIRTIO_F_RING_PACKED,
74 
75     /* This bit implies RARP isn't sent by QEMU out of band */
76     VIRTIO_NET_F_GUEST_ANNOUNCE,
77 
78     VIRTIO_NET_F_MQ,
79 
80     VHOST_INVALID_FEATURE_BIT
81 };
82 
83 static const int *vhost_net_get_feature_bits(struct vhost_net *net)
84 {
85     const int *feature_bits = 0;
86 
87     switch (net->nc->info->type) {
88     case NET_CLIENT_DRIVER_TAP:
89         feature_bits = kernel_feature_bits;
90         break;
91     case NET_CLIENT_DRIVER_VHOST_USER:
92         feature_bits = user_feature_bits;
93         break;
94 #ifdef CONFIG_VHOST_NET_VDPA
95     case NET_CLIENT_DRIVER_VHOST_VDPA:
96         feature_bits = vdpa_feature_bits;
97         break;
98 #endif
99     default:
100         error_report("Feature bits not defined for this type: %d",
101                 net->nc->info->type);
102         break;
103     }
104 
105     return feature_bits;
106 }
107 
108 uint64_t vhost_net_get_features(struct vhost_net *net, uint64_t features)
109 {
110     return vhost_get_features(&net->dev, vhost_net_get_feature_bits(net),
111             features);
112 }
113 int vhost_net_get_config(struct vhost_net *net,  uint8_t *config,
114                          uint32_t config_len)
115 {
116     return vhost_dev_get_config(&net->dev, config, config_len);
117 }
118 int vhost_net_set_config(struct vhost_net *net, const uint8_t *data,
119                          uint32_t offset, uint32_t size, uint32_t flags)
120 {
121     return vhost_dev_set_config(&net->dev, data, offset, size, flags);
122 }
123 
124 void vhost_net_ack_features(struct vhost_net *net, uint64_t features)
125 {
126     net->dev.acked_features = net->dev.backend_features;
127     vhost_ack_features(&net->dev, vhost_net_get_feature_bits(net), features);
128 }
129 
130 uint64_t vhost_net_get_max_queues(VHostNetState *net)
131 {
132     return net->dev.max_queues;
133 }
134 
135 uint64_t vhost_net_get_acked_features(VHostNetState *net)
136 {
137     return net->dev.acked_features;
138 }
139 
140 static int vhost_net_get_fd(NetClientState *backend)
141 {
142     switch (backend->info->type) {
143     case NET_CLIENT_DRIVER_TAP:
144         return tap_get_fd(backend);
145     default:
146         fprintf(stderr, "vhost-net requires tap backend\n");
147         return -ENOSYS;
148     }
149 }
150 
151 struct vhost_net *vhost_net_init(VhostNetOptions *options)
152 {
153     int r;
154     bool backend_kernel = options->backend_type == VHOST_BACKEND_TYPE_KERNEL;
155     struct vhost_net *net = g_new0(struct vhost_net, 1);
156     uint64_t features = 0;
157 
158     if (!options->net_backend) {
159         fprintf(stderr, "vhost-net requires net backend to be setup\n");
160         goto fail;
161     }
162     net->nc = options->net_backend;
163 
164     net->dev.max_queues = 1;
165     net->dev.nvqs = 2;
166     net->dev.vqs = net->vqs;
167 
168     if (backend_kernel) {
169         r = vhost_net_get_fd(options->net_backend);
170         if (r < 0) {
171             goto fail;
172         }
173         net->dev.backend_features = qemu_has_vnet_hdr(options->net_backend)
174             ? 0 : (1ULL << VHOST_NET_F_VIRTIO_NET_HDR);
175         net->backend = r;
176         net->dev.protocol_features = 0;
177     } else {
178         net->dev.backend_features = 0;
179         net->dev.protocol_features = 0;
180         net->backend = -1;
181 
182         /* vhost-user needs vq_index to initiate a specific queue pair */
183         net->dev.vq_index = net->nc->queue_index * net->dev.nvqs;
184     }
185 
186     r = vhost_dev_init(&net->dev, options->opaque,
187                        options->backend_type, options->busyloop_timeout);
188     if (r < 0) {
189         goto fail;
190     }
191     if (backend_kernel) {
192         if (!qemu_has_vnet_hdr_len(options->net_backend,
193                                sizeof(struct virtio_net_hdr_mrg_rxbuf))) {
194             net->dev.features &= ~(1ULL << VIRTIO_NET_F_MRG_RXBUF);
195         }
196         if (~net->dev.features & net->dev.backend_features) {
197             fprintf(stderr, "vhost lacks feature mask %" PRIu64
198                    " for backend\n",
199                    (uint64_t)(~net->dev.features & net->dev.backend_features));
200             goto fail;
201         }
202     }
203 
204     /* Set sane init value. Override when guest acks. */
205 #ifdef CONFIG_VHOST_NET_USER
206     if (net->nc->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
207         features = vhost_user_get_acked_features(net->nc);
208         if (~net->dev.features & features) {
209             fprintf(stderr, "vhost lacks feature mask %" PRIu64
210                     " for backend\n",
211                     (uint64_t)(~net->dev.features & features));
212             goto fail;
213         }
214     }
215 #endif
216 
217     vhost_net_ack_features(net, features);
218 
219     return net;
220 
221 fail:
222     vhost_dev_cleanup(&net->dev);
223     g_free(net);
224     return NULL;
225 }
226 
227 static void vhost_net_set_vq_index(struct vhost_net *net, int vq_index)
228 {
229     net->dev.vq_index = vq_index;
230 }
231 
232 static int vhost_net_start_one(struct vhost_net *net,
233                                VirtIODevice *dev)
234 {
235     struct vhost_vring_file file = { };
236     int r;
237 
238     net->dev.nvqs = 2;
239     net->dev.vqs = net->vqs;
240 
241     r = vhost_dev_enable_notifiers(&net->dev, dev);
242     if (r < 0) {
243         goto fail_notifiers;
244     }
245 
246     r = vhost_dev_start(&net->dev, dev);
247     if (r < 0) {
248         goto fail_start;
249     }
250 
251     if (net->nc->info->poll) {
252         net->nc->info->poll(net->nc, false);
253     }
254 
255     if (net->nc->info->type == NET_CLIENT_DRIVER_TAP) {
256         qemu_set_fd_handler(net->backend, NULL, NULL, NULL);
257         file.fd = net->backend;
258         for (file.index = 0; file.index < net->dev.nvqs; ++file.index) {
259             if (!virtio_queue_enabled(dev, net->dev.vq_index +
260                                       file.index)) {
261                 /* Queue might not be ready for start */
262                 continue;
263             }
264             r = vhost_net_set_backend(&net->dev, &file);
265             if (r < 0) {
266                 r = -errno;
267                 goto fail;
268             }
269         }
270     }
271     return 0;
272 fail:
273     file.fd = -1;
274     if (net->nc->info->type == NET_CLIENT_DRIVER_TAP) {
275         while (file.index-- > 0) {
276             if (!virtio_queue_enabled(dev, net->dev.vq_index +
277                                       file.index)) {
278                 /* Queue might not be ready for start */
279                 continue;
280             }
281             int r = vhost_net_set_backend(&net->dev, &file);
282             assert(r >= 0);
283         }
284     }
285     if (net->nc->info->poll) {
286         net->nc->info->poll(net->nc, true);
287     }
288     vhost_dev_stop(&net->dev, dev);
289 fail_start:
290     vhost_dev_disable_notifiers(&net->dev, dev);
291 fail_notifiers:
292     return r;
293 }
294 
295 static void vhost_net_stop_one(struct vhost_net *net,
296                                VirtIODevice *dev)
297 {
298     struct vhost_vring_file file = { .fd = -1 };
299 
300     if (net->nc->info->type == NET_CLIENT_DRIVER_TAP) {
301         for (file.index = 0; file.index < net->dev.nvqs; ++file.index) {
302             int r = vhost_net_set_backend(&net->dev, &file);
303             assert(r >= 0);
304         }
305     }
306     if (net->nc->info->poll) {
307         net->nc->info->poll(net->nc, true);
308     }
309     vhost_dev_stop(&net->dev, dev);
310     vhost_dev_disable_notifiers(&net->dev, dev);
311 }
312 
313 int vhost_net_start(VirtIODevice *dev, NetClientState *ncs,
314                     int total_queues)
315 {
316     BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(dev)));
317     VirtioBusState *vbus = VIRTIO_BUS(qbus);
318     VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus);
319     struct vhost_net *net;
320     int r, e, i;
321     NetClientState *peer;
322 
323     if (!k->set_guest_notifiers) {
324         error_report("binding does not support guest notifiers");
325         return -ENOSYS;
326     }
327 
328     for (i = 0; i < total_queues; i++) {
329 
330         peer = qemu_get_peer(ncs, i);
331         net = get_vhost_net(peer);
332         vhost_net_set_vq_index(net, i * 2);
333 
334         /* Suppress the masking guest notifiers on vhost user
335          * because vhost user doesn't interrupt masking/unmasking
336          * properly.
337          */
338         if (net->nc->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
339             dev->use_guest_notifier_mask = false;
340         }
341      }
342 
343     r = k->set_guest_notifiers(qbus->parent, total_queues * 2, true);
344     if (r < 0) {
345         error_report("Error binding guest notifier: %d", -r);
346         goto err;
347     }
348 
349     for (i = 0; i < total_queues; i++) {
350         peer = qemu_get_peer(ncs, i);
351         r = vhost_net_start_one(get_vhost_net(peer), dev);
352 
353         if (r < 0) {
354             goto err_start;
355         }
356 
357         if (peer->vring_enable) {
358             /* restore vring enable state */
359             r = vhost_set_vring_enable(peer, peer->vring_enable);
360 
361             if (r < 0) {
362                 goto err_start;
363             }
364         }
365     }
366 
367     return 0;
368 
369 err_start:
370     while (--i >= 0) {
371         peer = qemu_get_peer(ncs , i);
372         vhost_net_stop_one(get_vhost_net(peer), dev);
373     }
374     e = k->set_guest_notifiers(qbus->parent, total_queues * 2, false);
375     if (e < 0) {
376         fprintf(stderr, "vhost guest notifier cleanup failed: %d\n", e);
377         fflush(stderr);
378     }
379 err:
380     return r;
381 }
382 
383 void vhost_net_stop(VirtIODevice *dev, NetClientState *ncs,
384                     int total_queues)
385 {
386     BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(dev)));
387     VirtioBusState *vbus = VIRTIO_BUS(qbus);
388     VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus);
389     int i, r;
390 
391     for (i = 0; i < total_queues; i++) {
392         vhost_net_stop_one(get_vhost_net(ncs[i].peer), dev);
393     }
394 
395     r = k->set_guest_notifiers(qbus->parent, total_queues * 2, false);
396     if (r < 0) {
397         fprintf(stderr, "vhost guest notifier cleanup failed: %d\n", r);
398         fflush(stderr);
399     }
400     assert(r >= 0);
401 }
402 
403 void vhost_net_cleanup(struct vhost_net *net)
404 {
405     vhost_dev_cleanup(&net->dev);
406 }
407 
408 int vhost_net_notify_migration_done(struct vhost_net *net, char* mac_addr)
409 {
410     const VhostOps *vhost_ops = net->dev.vhost_ops;
411 
412     assert(vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
413     assert(vhost_ops->vhost_migration_done);
414 
415     return vhost_ops->vhost_migration_done(&net->dev, mac_addr);
416 }
417 
418 bool vhost_net_virtqueue_pending(VHostNetState *net, int idx)
419 {
420     return vhost_virtqueue_pending(&net->dev, idx);
421 }
422 
423 void vhost_net_virtqueue_mask(VHostNetState *net, VirtIODevice *dev,
424                               int idx, bool mask)
425 {
426     vhost_virtqueue_mask(&net->dev, dev, idx, mask);
427 }
428 
429 VHostNetState *get_vhost_net(NetClientState *nc)
430 {
431     VHostNetState *vhost_net = 0;
432 
433     if (!nc) {
434         return 0;
435     }
436 
437     switch (nc->info->type) {
438     case NET_CLIENT_DRIVER_TAP:
439         vhost_net = tap_get_vhost_net(nc);
440         break;
441 #ifdef CONFIG_VHOST_NET_USER
442     case NET_CLIENT_DRIVER_VHOST_USER:
443         vhost_net = vhost_user_get_vhost_net(nc);
444         assert(vhost_net);
445         break;
446 #endif
447 #ifdef CONFIG_VHOST_NET_VDPA
448     case NET_CLIENT_DRIVER_VHOST_VDPA:
449         vhost_net = vhost_vdpa_get_vhost_net(nc);
450         assert(vhost_net);
451         break;
452 #endif
453     default:
454         break;
455     }
456 
457     return vhost_net;
458 }
459 
460 int vhost_set_vring_enable(NetClientState *nc, int enable)
461 {
462     VHostNetState *net = get_vhost_net(nc);
463     const VhostOps *vhost_ops = net->dev.vhost_ops;
464 
465     nc->vring_enable = enable;
466 
467     if (vhost_ops && vhost_ops->vhost_set_vring_enable) {
468         return vhost_ops->vhost_set_vring_enable(&net->dev, enable);
469     }
470 
471     return 0;
472 }
473 
474 int vhost_net_set_mtu(struct vhost_net *net, uint16_t mtu)
475 {
476     const VhostOps *vhost_ops = net->dev.vhost_ops;
477 
478     if (!vhost_ops->vhost_net_set_mtu) {
479         return 0;
480     }
481 
482     return vhost_ops->vhost_net_set_mtu(&net->dev, mtu);
483 }
484