xref: /openbmc/qemu/hw/net/virtio-net.c (revision 7d87775f)
1 /*
2  * Virtio Network Device
3  *
4  * Copyright IBM, Corp. 2007
5  *
6  * Authors:
7  *  Anthony Liguori   <aliguori@us.ibm.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  */
13 
14 #include "qemu/osdep.h"
15 #include "qemu/atomic.h"
16 #include "qemu/iov.h"
17 #include "qemu/log.h"
18 #include "qemu/main-loop.h"
19 #include "qemu/module.h"
20 #include "hw/virtio/virtio.h"
21 #include "net/net.h"
22 #include "net/checksum.h"
23 #include "net/tap.h"
24 #include "qemu/error-report.h"
25 #include "qemu/timer.h"
26 #include "qemu/option.h"
27 #include "qemu/option_int.h"
28 #include "qemu/config-file.h"
29 #include "qapi/qmp/qdict.h"
30 #include "hw/virtio/virtio-net.h"
31 #include "net/vhost_net.h"
32 #include "net/announce.h"
33 #include "hw/virtio/virtio-bus.h"
34 #include "qapi/error.h"
35 #include "qapi/qapi-events-net.h"
36 #include "hw/qdev-properties.h"
37 #include "qapi/qapi-types-migration.h"
38 #include "qapi/qapi-events-migration.h"
39 #include "hw/virtio/virtio-access.h"
40 #include "migration/misc.h"
41 #include "standard-headers/linux/ethtool.h"
42 #include "sysemu/sysemu.h"
43 #include "sysemu/replay.h"
44 #include "trace.h"
45 #include "monitor/qdev.h"
46 #include "monitor/monitor.h"
47 #include "hw/pci/pci_device.h"
48 #include "net_rx_pkt.h"
49 #include "hw/virtio/vhost.h"
50 #include "sysemu/qtest.h"
51 
52 #define VIRTIO_NET_VM_VERSION    11
53 
54 /* previously fixed value */
55 #define VIRTIO_NET_RX_QUEUE_DEFAULT_SIZE 256
56 #define VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE 256
57 
58 /* for now, only allow larger queue_pairs; with virtio-1, guest can downsize */
59 #define VIRTIO_NET_RX_QUEUE_MIN_SIZE VIRTIO_NET_RX_QUEUE_DEFAULT_SIZE
60 #define VIRTIO_NET_TX_QUEUE_MIN_SIZE VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE
61 
62 #define VIRTIO_NET_IP4_ADDR_SIZE   8        /* ipv4 saddr + daddr */
63 
64 #define VIRTIO_NET_TCP_FLAG         0x3F
65 #define VIRTIO_NET_TCP_HDR_LENGTH   0xF000
66 
67 /* IPv4 max payload, 16 bits in the header */
68 #define VIRTIO_NET_MAX_IP4_PAYLOAD (65535 - sizeof(struct ip_header))
69 #define VIRTIO_NET_MAX_TCP_PAYLOAD 65535
70 
71 /* header length value in ip header without option */
72 #define VIRTIO_NET_IP4_HEADER_LENGTH 5
73 
74 #define VIRTIO_NET_IP6_ADDR_SIZE   32      /* ipv6 saddr + daddr */
75 #define VIRTIO_NET_MAX_IP6_PAYLOAD VIRTIO_NET_MAX_TCP_PAYLOAD
76 
77 /* Purge coalesced packets timer interval, This value affects the performance
78    a lot, and should be tuned carefully, '300000'(300us) is the recommended
79    value to pass the WHQL test, '50000' can gain 2x netperf throughput with
80    tso/gso/gro 'off'. */
81 #define VIRTIO_NET_RSC_DEFAULT_INTERVAL 300000
82 
83 #define VIRTIO_NET_RSS_SUPPORTED_HASHES (VIRTIO_NET_RSS_HASH_TYPE_IPv4 | \
84                                          VIRTIO_NET_RSS_HASH_TYPE_TCPv4 | \
85                                          VIRTIO_NET_RSS_HASH_TYPE_UDPv4 | \
86                                          VIRTIO_NET_RSS_HASH_TYPE_IPv6 | \
87                                          VIRTIO_NET_RSS_HASH_TYPE_TCPv6 | \
88                                          VIRTIO_NET_RSS_HASH_TYPE_UDPv6 | \
89                                          VIRTIO_NET_RSS_HASH_TYPE_IP_EX | \
90                                          VIRTIO_NET_RSS_HASH_TYPE_TCP_EX | \
91                                          VIRTIO_NET_RSS_HASH_TYPE_UDP_EX)
92 
93 static const VirtIOFeature feature_sizes[] = {
94     {.flags = 1ULL << VIRTIO_NET_F_MAC,
95      .end = endof(struct virtio_net_config, mac)},
96     {.flags = 1ULL << VIRTIO_NET_F_STATUS,
97      .end = endof(struct virtio_net_config, status)},
98     {.flags = 1ULL << VIRTIO_NET_F_MQ,
99      .end = endof(struct virtio_net_config, max_virtqueue_pairs)},
100     {.flags = 1ULL << VIRTIO_NET_F_MTU,
101      .end = endof(struct virtio_net_config, mtu)},
102     {.flags = 1ULL << VIRTIO_NET_F_SPEED_DUPLEX,
103      .end = endof(struct virtio_net_config, duplex)},
104     {.flags = (1ULL << VIRTIO_NET_F_RSS) | (1ULL << VIRTIO_NET_F_HASH_REPORT),
105      .end = endof(struct virtio_net_config, supported_hash_types)},
106     {}
107 };
108 
109 static const VirtIOConfigSizeParams cfg_size_params = {
110     .min_size = endof(struct virtio_net_config, mac),
111     .max_size = sizeof(struct virtio_net_config),
112     .feature_sizes = feature_sizes
113 };
114 
115 static VirtIONetQueue *virtio_net_get_subqueue(NetClientState *nc)
116 {
117     VirtIONet *n = qemu_get_nic_opaque(nc);
118 
119     return &n->vqs[nc->queue_index];
120 }
121 
122 static int vq2q(int queue_index)
123 {
124     return queue_index / 2;
125 }
126 
127 static void flush_or_purge_queued_packets(NetClientState *nc)
128 {
129     if (!nc->peer) {
130         return;
131     }
132 
133     qemu_flush_or_purge_queued_packets(nc->peer, true);
134     assert(!virtio_net_get_subqueue(nc)->async_tx.elem);
135 }
136 
137 /* TODO
138  * - we could suppress RX interrupt if we were so inclined.
139  */
140 
141 static void virtio_net_get_config(VirtIODevice *vdev, uint8_t *config)
142 {
143     VirtIONet *n = VIRTIO_NET(vdev);
144     struct virtio_net_config netcfg;
145     NetClientState *nc = qemu_get_queue(n->nic);
146     static const MACAddr zero = { .a = { 0, 0, 0, 0, 0, 0 } };
147 
148     int ret = 0;
149     memset(&netcfg, 0 , sizeof(struct virtio_net_config));
150     virtio_stw_p(vdev, &netcfg.status, n->status);
151     virtio_stw_p(vdev, &netcfg.max_virtqueue_pairs, n->max_queue_pairs);
152     virtio_stw_p(vdev, &netcfg.mtu, n->net_conf.mtu);
153     memcpy(netcfg.mac, n->mac, ETH_ALEN);
154     virtio_stl_p(vdev, &netcfg.speed, n->net_conf.speed);
155     netcfg.duplex = n->net_conf.duplex;
156     netcfg.rss_max_key_size = VIRTIO_NET_RSS_MAX_KEY_SIZE;
157     virtio_stw_p(vdev, &netcfg.rss_max_indirection_table_length,
158                  virtio_host_has_feature(vdev, VIRTIO_NET_F_RSS) ?
159                  VIRTIO_NET_RSS_MAX_TABLE_LEN : 1);
160     virtio_stl_p(vdev, &netcfg.supported_hash_types,
161                  VIRTIO_NET_RSS_SUPPORTED_HASHES);
162     memcpy(config, &netcfg, n->config_size);
163 
164     /*
165      * Is this VDPA? No peer means not VDPA: there's no way to
166      * disconnect/reconnect a VDPA peer.
167      */
168     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_VDPA) {
169         ret = vhost_net_get_config(get_vhost_net(nc->peer), (uint8_t *)&netcfg,
170                                    n->config_size);
171         if (ret == -1) {
172             return;
173         }
174 
175         /*
176          * Some NIC/kernel combinations present 0 as the mac address.  As that
177          * is not a legal address, try to proceed with the address from the
178          * QEMU command line in the hope that the address has been configured
179          * correctly elsewhere - just not reported by the device.
180          */
181         if (memcmp(&netcfg.mac, &zero, sizeof(zero)) == 0) {
182             info_report("Zero hardware mac address detected. Ignoring.");
183             memcpy(netcfg.mac, n->mac, ETH_ALEN);
184         }
185 
186         netcfg.status |= virtio_tswap16(vdev,
187                                         n->status & VIRTIO_NET_S_ANNOUNCE);
188         memcpy(config, &netcfg, n->config_size);
189     }
190 }
191 
192 static void virtio_net_set_config(VirtIODevice *vdev, const uint8_t *config)
193 {
194     VirtIONet *n = VIRTIO_NET(vdev);
195     struct virtio_net_config netcfg = {};
196     NetClientState *nc = qemu_get_queue(n->nic);
197 
198     memcpy(&netcfg, config, n->config_size);
199 
200     if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR) &&
201         !virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1) &&
202         memcmp(netcfg.mac, n->mac, ETH_ALEN)) {
203         memcpy(n->mac, netcfg.mac, ETH_ALEN);
204         qemu_format_nic_info_str(qemu_get_queue(n->nic), n->mac);
205     }
206 
207     /*
208      * Is this VDPA? No peer means not VDPA: there's no way to
209      * disconnect/reconnect a VDPA peer.
210      */
211     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_VDPA) {
212         vhost_net_set_config(get_vhost_net(nc->peer),
213                              (uint8_t *)&netcfg, 0, n->config_size,
214                              VHOST_SET_CONFIG_TYPE_FRONTEND);
215       }
216 }
217 
218 static bool virtio_net_started(VirtIONet *n, uint8_t status)
219 {
220     VirtIODevice *vdev = VIRTIO_DEVICE(n);
221     return (status & VIRTIO_CONFIG_S_DRIVER_OK) &&
222         (n->status & VIRTIO_NET_S_LINK_UP) && vdev->vm_running;
223 }
224 
225 static void virtio_net_announce_notify(VirtIONet *net)
226 {
227     VirtIODevice *vdev = VIRTIO_DEVICE(net);
228     trace_virtio_net_announce_notify();
229 
230     net->status |= VIRTIO_NET_S_ANNOUNCE;
231     virtio_notify_config(vdev);
232 }
233 
234 static void virtio_net_announce_timer(void *opaque)
235 {
236     VirtIONet *n = opaque;
237     trace_virtio_net_announce_timer(n->announce_timer.round);
238 
239     n->announce_timer.round--;
240     virtio_net_announce_notify(n);
241 }
242 
243 static void virtio_net_announce(NetClientState *nc)
244 {
245     VirtIONet *n = qemu_get_nic_opaque(nc);
246     VirtIODevice *vdev = VIRTIO_DEVICE(n);
247 
248     /*
249      * Make sure the virtio migration announcement timer isn't running
250      * If it is, let it trigger announcement so that we do not cause
251      * confusion.
252      */
253     if (n->announce_timer.round) {
254         return;
255     }
256 
257     if (virtio_vdev_has_feature(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE) &&
258         virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) {
259             virtio_net_announce_notify(n);
260     }
261 }
262 
263 static void virtio_net_vhost_status(VirtIONet *n, uint8_t status)
264 {
265     VirtIODevice *vdev = VIRTIO_DEVICE(n);
266     NetClientState *nc = qemu_get_queue(n->nic);
267     int queue_pairs = n->multiqueue ? n->max_queue_pairs : 1;
268     int cvq = virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) ?
269               n->max_ncs - n->max_queue_pairs : 0;
270 
271     if (!get_vhost_net(nc->peer)) {
272         return;
273     }
274 
275     if ((virtio_net_started(n, status) && !nc->peer->link_down) ==
276         !!n->vhost_started) {
277         return;
278     }
279     if (!n->vhost_started) {
280         int r, i;
281 
282         if (n->needs_vnet_hdr_swap) {
283             error_report("backend does not support %s vnet headers; "
284                          "falling back on userspace virtio",
285                          virtio_is_big_endian(vdev) ? "BE" : "LE");
286             return;
287         }
288 
289         /* Any packets outstanding? Purge them to avoid touching rings
290          * when vhost is running.
291          */
292         for (i = 0;  i < queue_pairs; i++) {
293             NetClientState *qnc = qemu_get_subqueue(n->nic, i);
294 
295             /* Purge both directions: TX and RX. */
296             qemu_net_queue_purge(qnc->peer->incoming_queue, qnc);
297             qemu_net_queue_purge(qnc->incoming_queue, qnc->peer);
298         }
299 
300         if (virtio_has_feature(vdev->guest_features, VIRTIO_NET_F_MTU)) {
301             r = vhost_net_set_mtu(get_vhost_net(nc->peer), n->net_conf.mtu);
302             if (r < 0) {
303                 error_report("%uBytes MTU not supported by the backend",
304                              n->net_conf.mtu);
305 
306                 return;
307             }
308         }
309 
310         n->vhost_started = 1;
311         r = vhost_net_start(vdev, n->nic->ncs, queue_pairs, cvq);
312         if (r < 0) {
313             error_report("unable to start vhost net: %d: "
314                          "falling back on userspace virtio", -r);
315             n->vhost_started = 0;
316         }
317     } else {
318         vhost_net_stop(vdev, n->nic->ncs, queue_pairs, cvq);
319         n->vhost_started = 0;
320     }
321 }
322 
323 static int virtio_net_set_vnet_endian_one(VirtIODevice *vdev,
324                                           NetClientState *peer,
325                                           bool enable)
326 {
327     if (virtio_is_big_endian(vdev)) {
328         return qemu_set_vnet_be(peer, enable);
329     } else {
330         return qemu_set_vnet_le(peer, enable);
331     }
332 }
333 
334 static bool virtio_net_set_vnet_endian(VirtIODevice *vdev, NetClientState *ncs,
335                                        int queue_pairs, bool enable)
336 {
337     int i;
338 
339     for (i = 0; i < queue_pairs; i++) {
340         if (virtio_net_set_vnet_endian_one(vdev, ncs[i].peer, enable) < 0 &&
341             enable) {
342             while (--i >= 0) {
343                 virtio_net_set_vnet_endian_one(vdev, ncs[i].peer, false);
344             }
345 
346             return true;
347         }
348     }
349 
350     return false;
351 }
352 
353 static void virtio_net_vnet_endian_status(VirtIONet *n, uint8_t status)
354 {
355     VirtIODevice *vdev = VIRTIO_DEVICE(n);
356     int queue_pairs = n->multiqueue ? n->max_queue_pairs : 1;
357 
358     if (virtio_net_started(n, status)) {
359         /* Before using the device, we tell the network backend about the
360          * endianness to use when parsing vnet headers. If the backend
361          * can't do it, we fallback onto fixing the headers in the core
362          * virtio-net code.
363          */
364         n->needs_vnet_hdr_swap = n->has_vnet_hdr &&
365                                  virtio_net_set_vnet_endian(vdev, n->nic->ncs,
366                                                             queue_pairs, true);
367     } else if (virtio_net_started(n, vdev->status)) {
368         /* After using the device, we need to reset the network backend to
369          * the default (guest native endianness), otherwise the guest may
370          * lose network connectivity if it is rebooted into a different
371          * endianness.
372          */
373         virtio_net_set_vnet_endian(vdev, n->nic->ncs, queue_pairs, false);
374     }
375 }
376 
377 static void virtio_net_drop_tx_queue_data(VirtIODevice *vdev, VirtQueue *vq)
378 {
379     unsigned int dropped = virtqueue_drop_all(vq);
380     if (dropped) {
381         virtio_notify(vdev, vq);
382     }
383 }
384 
385 static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status)
386 {
387     VirtIONet *n = VIRTIO_NET(vdev);
388     VirtIONetQueue *q;
389     int i;
390     uint8_t queue_status;
391 
392     virtio_net_vnet_endian_status(n, status);
393     virtio_net_vhost_status(n, status);
394 
395     for (i = 0; i < n->max_queue_pairs; i++) {
396         NetClientState *ncs = qemu_get_subqueue(n->nic, i);
397         bool queue_started;
398         q = &n->vqs[i];
399 
400         if ((!n->multiqueue && i != 0) || i >= n->curr_queue_pairs) {
401             queue_status = 0;
402         } else {
403             queue_status = status;
404         }
405         queue_started =
406             virtio_net_started(n, queue_status) && !n->vhost_started;
407 
408         if (queue_started) {
409             qemu_flush_queued_packets(ncs);
410         }
411 
412         if (!q->tx_waiting) {
413             continue;
414         }
415 
416         if (queue_started) {
417             if (q->tx_timer) {
418                 timer_mod(q->tx_timer,
419                                qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + n->tx_timeout);
420             } else {
421                 replay_bh_schedule_event(q->tx_bh);
422             }
423         } else {
424             if (q->tx_timer) {
425                 timer_del(q->tx_timer);
426             } else {
427                 qemu_bh_cancel(q->tx_bh);
428             }
429             if ((n->status & VIRTIO_NET_S_LINK_UP) == 0 &&
430                 (queue_status & VIRTIO_CONFIG_S_DRIVER_OK) &&
431                 vdev->vm_running) {
432                 /* if tx is waiting we are likely have some packets in tx queue
433                  * and disabled notification */
434                 q->tx_waiting = 0;
435                 virtio_queue_set_notification(q->tx_vq, 1);
436                 virtio_net_drop_tx_queue_data(vdev, q->tx_vq);
437             }
438         }
439     }
440 }
441 
442 static void virtio_net_set_link_status(NetClientState *nc)
443 {
444     VirtIONet *n = qemu_get_nic_opaque(nc);
445     VirtIODevice *vdev = VIRTIO_DEVICE(n);
446     uint16_t old_status = n->status;
447 
448     if (nc->link_down)
449         n->status &= ~VIRTIO_NET_S_LINK_UP;
450     else
451         n->status |= VIRTIO_NET_S_LINK_UP;
452 
453     if (n->status != old_status)
454         virtio_notify_config(vdev);
455 
456     virtio_net_set_status(vdev, vdev->status);
457 }
458 
459 static void rxfilter_notify(NetClientState *nc)
460 {
461     VirtIONet *n = qemu_get_nic_opaque(nc);
462 
463     if (nc->rxfilter_notify_enabled) {
464         char *path = object_get_canonical_path(OBJECT(n->qdev));
465         qapi_event_send_nic_rx_filter_changed(n->netclient_name, path);
466         g_free(path);
467 
468         /* disable event notification to avoid events flooding */
469         nc->rxfilter_notify_enabled = 0;
470     }
471 }
472 
473 static intList *get_vlan_table(VirtIONet *n)
474 {
475     intList *list;
476     int i, j;
477 
478     list = NULL;
479     for (i = 0; i < MAX_VLAN >> 5; i++) {
480         for (j = 0; n->vlans[i] && j <= 0x1f; j++) {
481             if (n->vlans[i] & (1U << j)) {
482                 QAPI_LIST_PREPEND(list, (i << 5) + j);
483             }
484         }
485     }
486 
487     return list;
488 }
489 
490 static RxFilterInfo *virtio_net_query_rxfilter(NetClientState *nc)
491 {
492     VirtIONet *n = qemu_get_nic_opaque(nc);
493     VirtIODevice *vdev = VIRTIO_DEVICE(n);
494     RxFilterInfo *info;
495     strList *str_list;
496     int i;
497 
498     info = g_malloc0(sizeof(*info));
499     info->name = g_strdup(nc->name);
500     info->promiscuous = n->promisc;
501 
502     if (n->nouni) {
503         info->unicast = RX_STATE_NONE;
504     } else if (n->alluni) {
505         info->unicast = RX_STATE_ALL;
506     } else {
507         info->unicast = RX_STATE_NORMAL;
508     }
509 
510     if (n->nomulti) {
511         info->multicast = RX_STATE_NONE;
512     } else if (n->allmulti) {
513         info->multicast = RX_STATE_ALL;
514     } else {
515         info->multicast = RX_STATE_NORMAL;
516     }
517 
518     info->broadcast_allowed = n->nobcast;
519     info->multicast_overflow = n->mac_table.multi_overflow;
520     info->unicast_overflow = n->mac_table.uni_overflow;
521 
522     info->main_mac = qemu_mac_strdup_printf(n->mac);
523 
524     str_list = NULL;
525     for (i = 0; i < n->mac_table.first_multi; i++) {
526         QAPI_LIST_PREPEND(str_list,
527                       qemu_mac_strdup_printf(n->mac_table.macs + i * ETH_ALEN));
528     }
529     info->unicast_table = str_list;
530 
531     str_list = NULL;
532     for (i = n->mac_table.first_multi; i < n->mac_table.in_use; i++) {
533         QAPI_LIST_PREPEND(str_list,
534                       qemu_mac_strdup_printf(n->mac_table.macs + i * ETH_ALEN));
535     }
536     info->multicast_table = str_list;
537     info->vlan_table = get_vlan_table(n);
538 
539     if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_VLAN)) {
540         info->vlan = RX_STATE_ALL;
541     } else if (!info->vlan_table) {
542         info->vlan = RX_STATE_NONE;
543     } else {
544         info->vlan = RX_STATE_NORMAL;
545     }
546 
547     /* enable event notification after query */
548     nc->rxfilter_notify_enabled = 1;
549 
550     return info;
551 }
552 
553 static void virtio_net_queue_reset(VirtIODevice *vdev, uint32_t queue_index)
554 {
555     VirtIONet *n = VIRTIO_NET(vdev);
556     NetClientState *nc;
557 
558     /* validate queue_index and skip for cvq */
559     if (queue_index >= n->max_queue_pairs * 2) {
560         return;
561     }
562 
563     nc = qemu_get_subqueue(n->nic, vq2q(queue_index));
564 
565     if (!nc->peer) {
566         return;
567     }
568 
569     if (get_vhost_net(nc->peer) &&
570         nc->peer->info->type == NET_CLIENT_DRIVER_TAP) {
571         vhost_net_virtqueue_reset(vdev, nc, queue_index);
572     }
573 
574     flush_or_purge_queued_packets(nc);
575 }
576 
577 static void virtio_net_queue_enable(VirtIODevice *vdev, uint32_t queue_index)
578 {
579     VirtIONet *n = VIRTIO_NET(vdev);
580     NetClientState *nc;
581     int r;
582 
583     /* validate queue_index and skip for cvq */
584     if (queue_index >= n->max_queue_pairs * 2) {
585         return;
586     }
587 
588     nc = qemu_get_subqueue(n->nic, vq2q(queue_index));
589 
590     if (!nc->peer || !vdev->vhost_started) {
591         return;
592     }
593 
594     if (get_vhost_net(nc->peer) &&
595         nc->peer->info->type == NET_CLIENT_DRIVER_TAP) {
596         r = vhost_net_virtqueue_restart(vdev, nc, queue_index);
597         if (r < 0) {
598             error_report("unable to restart vhost net virtqueue: %d, "
599                             "when resetting the queue", queue_index);
600         }
601     }
602 }
603 
604 static void peer_test_vnet_hdr(VirtIONet *n)
605 {
606     NetClientState *nc = qemu_get_queue(n->nic);
607     if (!nc->peer) {
608         return;
609     }
610 
611     n->has_vnet_hdr = qemu_has_vnet_hdr(nc->peer);
612 }
613 
614 static int peer_has_vnet_hdr(VirtIONet *n)
615 {
616     return n->has_vnet_hdr;
617 }
618 
619 static int peer_has_ufo(VirtIONet *n)
620 {
621     if (!peer_has_vnet_hdr(n))
622         return 0;
623 
624     n->has_ufo = qemu_has_ufo(qemu_get_queue(n->nic)->peer);
625 
626     return n->has_ufo;
627 }
628 
629 static int peer_has_uso(VirtIONet *n)
630 {
631     if (!peer_has_vnet_hdr(n)) {
632         return 0;
633     }
634 
635     return qemu_has_uso(qemu_get_queue(n->nic)->peer);
636 }
637 
638 static void virtio_net_set_mrg_rx_bufs(VirtIONet *n, int mergeable_rx_bufs,
639                                        int version_1, int hash_report)
640 {
641     int i;
642     NetClientState *nc;
643 
644     n->mergeable_rx_bufs = mergeable_rx_bufs;
645 
646     if (version_1) {
647         n->guest_hdr_len = hash_report ?
648             sizeof(struct virtio_net_hdr_v1_hash) :
649             sizeof(struct virtio_net_hdr_mrg_rxbuf);
650         n->rss_data.populate_hash = !!hash_report;
651     } else {
652         n->guest_hdr_len = n->mergeable_rx_bufs ?
653             sizeof(struct virtio_net_hdr_mrg_rxbuf) :
654             sizeof(struct virtio_net_hdr);
655         n->rss_data.populate_hash = false;
656     }
657 
658     for (i = 0; i < n->max_queue_pairs; i++) {
659         nc = qemu_get_subqueue(n->nic, i);
660 
661         if (peer_has_vnet_hdr(n) &&
662             qemu_has_vnet_hdr_len(nc->peer, n->guest_hdr_len)) {
663             qemu_set_vnet_hdr_len(nc->peer, n->guest_hdr_len);
664             n->host_hdr_len = n->guest_hdr_len;
665         }
666     }
667 }
668 
669 static int virtio_net_max_tx_queue_size(VirtIONet *n)
670 {
671     NetClientState *peer = n->nic_conf.peers.ncs[0];
672 
673     /*
674      * Backends other than vhost-user or vhost-vdpa don't support max queue
675      * size.
676      */
677     if (!peer) {
678         return VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE;
679     }
680 
681     switch(peer->info->type) {
682     case NET_CLIENT_DRIVER_VHOST_USER:
683     case NET_CLIENT_DRIVER_VHOST_VDPA:
684         return VIRTQUEUE_MAX_SIZE;
685     default:
686         return VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE;
687     };
688 }
689 
690 static int peer_attach(VirtIONet *n, int index)
691 {
692     NetClientState *nc = qemu_get_subqueue(n->nic, index);
693 
694     if (!nc->peer) {
695         return 0;
696     }
697 
698     if (nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
699         vhost_set_vring_enable(nc->peer, 1);
700     }
701 
702     if (nc->peer->info->type != NET_CLIENT_DRIVER_TAP) {
703         return 0;
704     }
705 
706     if (n->max_queue_pairs == 1) {
707         return 0;
708     }
709 
710     return tap_enable(nc->peer);
711 }
712 
713 static int peer_detach(VirtIONet *n, int index)
714 {
715     NetClientState *nc = qemu_get_subqueue(n->nic, index);
716 
717     if (!nc->peer) {
718         return 0;
719     }
720 
721     if (nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
722         vhost_set_vring_enable(nc->peer, 0);
723     }
724 
725     if (nc->peer->info->type !=  NET_CLIENT_DRIVER_TAP) {
726         return 0;
727     }
728 
729     return tap_disable(nc->peer);
730 }
731 
732 static void virtio_net_set_queue_pairs(VirtIONet *n)
733 {
734     int i;
735     int r;
736 
737     if (n->nic->peer_deleted) {
738         return;
739     }
740 
741     for (i = 0; i < n->max_queue_pairs; i++) {
742         if (i < n->curr_queue_pairs) {
743             r = peer_attach(n, i);
744             assert(!r);
745         } else {
746             r = peer_detach(n, i);
747             assert(!r);
748         }
749     }
750 }
751 
752 static void virtio_net_set_multiqueue(VirtIONet *n, int multiqueue);
753 
754 static uint64_t virtio_net_get_features(VirtIODevice *vdev, uint64_t features,
755                                         Error **errp)
756 {
757     VirtIONet *n = VIRTIO_NET(vdev);
758     NetClientState *nc = qemu_get_queue(n->nic);
759 
760     /* Firstly sync all virtio-net possible supported features */
761     features |= n->host_features;
762 
763     virtio_add_feature(&features, VIRTIO_NET_F_MAC);
764 
765     if (!peer_has_vnet_hdr(n)) {
766         virtio_clear_feature(&features, VIRTIO_NET_F_CSUM);
767         virtio_clear_feature(&features, VIRTIO_NET_F_HOST_TSO4);
768         virtio_clear_feature(&features, VIRTIO_NET_F_HOST_TSO6);
769         virtio_clear_feature(&features, VIRTIO_NET_F_HOST_ECN);
770 
771         virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_CSUM);
772         virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_TSO4);
773         virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_TSO6);
774         virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_ECN);
775 
776         virtio_clear_feature(&features, VIRTIO_NET_F_HOST_USO);
777         virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_USO4);
778         virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_USO6);
779 
780         virtio_clear_feature(&features, VIRTIO_NET_F_HASH_REPORT);
781     }
782 
783     if (!peer_has_vnet_hdr(n) || !peer_has_ufo(n)) {
784         virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_UFO);
785         virtio_clear_feature(&features, VIRTIO_NET_F_HOST_UFO);
786     }
787 
788     if (!peer_has_uso(n)) {
789         virtio_clear_feature(&features, VIRTIO_NET_F_HOST_USO);
790         virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_USO4);
791         virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_USO6);
792     }
793 
794     if (!get_vhost_net(nc->peer)) {
795         return features;
796     }
797 
798     if (!ebpf_rss_is_loaded(&n->ebpf_rss)) {
799         virtio_clear_feature(&features, VIRTIO_NET_F_RSS);
800     }
801     features = vhost_net_get_features(get_vhost_net(nc->peer), features);
802     vdev->backend_features = features;
803 
804     if (n->mtu_bypass_backend &&
805             (n->host_features & 1ULL << VIRTIO_NET_F_MTU)) {
806         features |= (1ULL << VIRTIO_NET_F_MTU);
807     }
808 
809     /*
810      * Since GUEST_ANNOUNCE is emulated the feature bit could be set without
811      * enabled. This happens in the vDPA case.
812      *
813      * Make sure the feature set is not incoherent, as the driver could refuse
814      * to start.
815      *
816      * TODO: QEMU is able to emulate a CVQ just for guest_announce purposes,
817      * helping guest to notify the new location with vDPA devices that does not
818      * support it.
819      */
820     if (!virtio_has_feature(vdev->backend_features, VIRTIO_NET_F_CTRL_VQ)) {
821         virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_ANNOUNCE);
822     }
823 
824     return features;
825 }
826 
827 static uint64_t virtio_net_bad_features(VirtIODevice *vdev)
828 {
829     uint64_t features = 0;
830 
831     /* Linux kernel 2.6.25.  It understood MAC (as everyone must),
832      * but also these: */
833     virtio_add_feature(&features, VIRTIO_NET_F_MAC);
834     virtio_add_feature(&features, VIRTIO_NET_F_CSUM);
835     virtio_add_feature(&features, VIRTIO_NET_F_HOST_TSO4);
836     virtio_add_feature(&features, VIRTIO_NET_F_HOST_TSO6);
837     virtio_add_feature(&features, VIRTIO_NET_F_HOST_ECN);
838 
839     return features;
840 }
841 
842 static void virtio_net_apply_guest_offloads(VirtIONet *n)
843 {
844     qemu_set_offload(qemu_get_queue(n->nic)->peer,
845             !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_CSUM)),
846             !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_TSO4)),
847             !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_TSO6)),
848             !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_ECN)),
849             !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_UFO)),
850             !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_USO4)),
851             !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_USO6)));
852 }
853 
854 static uint64_t virtio_net_guest_offloads_by_features(uint64_t features)
855 {
856     static const uint64_t guest_offloads_mask =
857         (1ULL << VIRTIO_NET_F_GUEST_CSUM) |
858         (1ULL << VIRTIO_NET_F_GUEST_TSO4) |
859         (1ULL << VIRTIO_NET_F_GUEST_TSO6) |
860         (1ULL << VIRTIO_NET_F_GUEST_ECN)  |
861         (1ULL << VIRTIO_NET_F_GUEST_UFO)  |
862         (1ULL << VIRTIO_NET_F_GUEST_USO4) |
863         (1ULL << VIRTIO_NET_F_GUEST_USO6);
864 
865     return guest_offloads_mask & features;
866 }
867 
868 uint64_t virtio_net_supported_guest_offloads(const VirtIONet *n)
869 {
870     VirtIODevice *vdev = VIRTIO_DEVICE(n);
871     return virtio_net_guest_offloads_by_features(vdev->guest_features);
872 }
873 
874 typedef struct {
875     VirtIONet *n;
876     DeviceState *dev;
877 } FailoverDevice;
878 
879 /**
880  * Set the failover primary device
881  *
882  * @opaque: FailoverId to setup
883  * @opts: opts for device we are handling
884  * @errp: returns an error if this function fails
885  */
886 static int failover_set_primary(DeviceState *dev, void *opaque)
887 {
888     FailoverDevice *fdev = opaque;
889     PCIDevice *pci_dev = (PCIDevice *)
890         object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE);
891 
892     if (!pci_dev) {
893         return 0;
894     }
895 
896     if (!g_strcmp0(pci_dev->failover_pair_id, fdev->n->netclient_name)) {
897         fdev->dev = dev;
898         return 1;
899     }
900 
901     return 0;
902 }
903 
904 /**
905  * Find the primary device for this failover virtio-net
906  *
907  * @n: VirtIONet device
908  * @errp: returns an error if this function fails
909  */
910 static DeviceState *failover_find_primary_device(VirtIONet *n)
911 {
912     FailoverDevice fdev = {
913         .n = n,
914     };
915 
916     qbus_walk_children(sysbus_get_default(), failover_set_primary, NULL,
917                        NULL, NULL, &fdev);
918     return fdev.dev;
919 }
920 
921 static void failover_add_primary(VirtIONet *n, Error **errp)
922 {
923     Error *err = NULL;
924     DeviceState *dev = failover_find_primary_device(n);
925 
926     if (dev) {
927         return;
928     }
929 
930     if (!n->primary_opts) {
931         error_setg(errp, "Primary device not found");
932         error_append_hint(errp, "Virtio-net failover will not work. Make "
933                           "sure primary device has parameter"
934                           " failover_pair_id=%s\n", n->netclient_name);
935         return;
936     }
937 
938     dev = qdev_device_add_from_qdict(n->primary_opts,
939                                      n->primary_opts_from_json,
940                                      &err);
941     if (err) {
942         qobject_unref(n->primary_opts);
943         n->primary_opts = NULL;
944     } else {
945         object_unref(OBJECT(dev));
946     }
947     error_propagate(errp, err);
948 }
949 
950 static void virtio_net_set_features(VirtIODevice *vdev, uint64_t features)
951 {
952     VirtIONet *n = VIRTIO_NET(vdev);
953     Error *err = NULL;
954     int i;
955 
956     if (n->mtu_bypass_backend &&
957             !virtio_has_feature(vdev->backend_features, VIRTIO_NET_F_MTU)) {
958         features &= ~(1ULL << VIRTIO_NET_F_MTU);
959     }
960 
961     virtio_net_set_multiqueue(n,
962                               virtio_has_feature(features, VIRTIO_NET_F_RSS) ||
963                               virtio_has_feature(features, VIRTIO_NET_F_MQ));
964 
965     virtio_net_set_mrg_rx_bufs(n,
966                                virtio_has_feature(features,
967                                                   VIRTIO_NET_F_MRG_RXBUF),
968                                virtio_has_feature(features,
969                                                   VIRTIO_F_VERSION_1),
970                                virtio_has_feature(features,
971                                                   VIRTIO_NET_F_HASH_REPORT));
972 
973     n->rsc4_enabled = virtio_has_feature(features, VIRTIO_NET_F_RSC_EXT) &&
974         virtio_has_feature(features, VIRTIO_NET_F_GUEST_TSO4);
975     n->rsc6_enabled = virtio_has_feature(features, VIRTIO_NET_F_RSC_EXT) &&
976         virtio_has_feature(features, VIRTIO_NET_F_GUEST_TSO6);
977     n->rss_data.redirect = virtio_has_feature(features, VIRTIO_NET_F_RSS);
978 
979     if (n->has_vnet_hdr) {
980         n->curr_guest_offloads =
981             virtio_net_guest_offloads_by_features(features);
982         virtio_net_apply_guest_offloads(n);
983     }
984 
985     for (i = 0;  i < n->max_queue_pairs; i++) {
986         NetClientState *nc = qemu_get_subqueue(n->nic, i);
987 
988         if (!get_vhost_net(nc->peer)) {
989             continue;
990         }
991         vhost_net_ack_features(get_vhost_net(nc->peer), features);
992 
993         /*
994          * keep acked_features in NetVhostUserState up-to-date so it
995          * can't miss any features configured by guest virtio driver.
996          */
997         vhost_net_save_acked_features(nc->peer);
998     }
999 
1000     if (!virtio_has_feature(features, VIRTIO_NET_F_CTRL_VLAN)) {
1001         memset(n->vlans, 0xff, MAX_VLAN >> 3);
1002     }
1003 
1004     if (virtio_has_feature(features, VIRTIO_NET_F_STANDBY)) {
1005         qapi_event_send_failover_negotiated(n->netclient_name);
1006         qatomic_set(&n->failover_primary_hidden, false);
1007         failover_add_primary(n, &err);
1008         if (err) {
1009             if (!qtest_enabled()) {
1010                 warn_report_err(err);
1011             } else {
1012                 error_free(err);
1013             }
1014         }
1015     }
1016 }
1017 
1018 static int virtio_net_handle_rx_mode(VirtIONet *n, uint8_t cmd,
1019                                      struct iovec *iov, unsigned int iov_cnt)
1020 {
1021     uint8_t on;
1022     size_t s;
1023     NetClientState *nc = qemu_get_queue(n->nic);
1024 
1025     s = iov_to_buf(iov, iov_cnt, 0, &on, sizeof(on));
1026     if (s != sizeof(on)) {
1027         return VIRTIO_NET_ERR;
1028     }
1029 
1030     if (cmd == VIRTIO_NET_CTRL_RX_PROMISC) {
1031         n->promisc = on;
1032     } else if (cmd == VIRTIO_NET_CTRL_RX_ALLMULTI) {
1033         n->allmulti = on;
1034     } else if (cmd == VIRTIO_NET_CTRL_RX_ALLUNI) {
1035         n->alluni = on;
1036     } else if (cmd == VIRTIO_NET_CTRL_RX_NOMULTI) {
1037         n->nomulti = on;
1038     } else if (cmd == VIRTIO_NET_CTRL_RX_NOUNI) {
1039         n->nouni = on;
1040     } else if (cmd == VIRTIO_NET_CTRL_RX_NOBCAST) {
1041         n->nobcast = on;
1042     } else {
1043         return VIRTIO_NET_ERR;
1044     }
1045 
1046     rxfilter_notify(nc);
1047 
1048     return VIRTIO_NET_OK;
1049 }
1050 
1051 static int virtio_net_handle_offloads(VirtIONet *n, uint8_t cmd,
1052                                      struct iovec *iov, unsigned int iov_cnt)
1053 {
1054     VirtIODevice *vdev = VIRTIO_DEVICE(n);
1055     uint64_t offloads;
1056     size_t s;
1057 
1058     if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)) {
1059         return VIRTIO_NET_ERR;
1060     }
1061 
1062     s = iov_to_buf(iov, iov_cnt, 0, &offloads, sizeof(offloads));
1063     if (s != sizeof(offloads)) {
1064         return VIRTIO_NET_ERR;
1065     }
1066 
1067     if (cmd == VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET) {
1068         uint64_t supported_offloads;
1069 
1070         offloads = virtio_ldq_p(vdev, &offloads);
1071 
1072         if (!n->has_vnet_hdr) {
1073             return VIRTIO_NET_ERR;
1074         }
1075 
1076         n->rsc4_enabled = virtio_has_feature(offloads, VIRTIO_NET_F_RSC_EXT) &&
1077             virtio_has_feature(offloads, VIRTIO_NET_F_GUEST_TSO4);
1078         n->rsc6_enabled = virtio_has_feature(offloads, VIRTIO_NET_F_RSC_EXT) &&
1079             virtio_has_feature(offloads, VIRTIO_NET_F_GUEST_TSO6);
1080         virtio_clear_feature(&offloads, VIRTIO_NET_F_RSC_EXT);
1081 
1082         supported_offloads = virtio_net_supported_guest_offloads(n);
1083         if (offloads & ~supported_offloads) {
1084             return VIRTIO_NET_ERR;
1085         }
1086 
1087         n->curr_guest_offloads = offloads;
1088         virtio_net_apply_guest_offloads(n);
1089 
1090         return VIRTIO_NET_OK;
1091     } else {
1092         return VIRTIO_NET_ERR;
1093     }
1094 }
1095 
1096 static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd,
1097                                  struct iovec *iov, unsigned int iov_cnt)
1098 {
1099     VirtIODevice *vdev = VIRTIO_DEVICE(n);
1100     struct virtio_net_ctrl_mac mac_data;
1101     size_t s;
1102     NetClientState *nc = qemu_get_queue(n->nic);
1103 
1104     if (cmd == VIRTIO_NET_CTRL_MAC_ADDR_SET) {
1105         if (iov_size(iov, iov_cnt) != sizeof(n->mac)) {
1106             return VIRTIO_NET_ERR;
1107         }
1108         s = iov_to_buf(iov, iov_cnt, 0, &n->mac, sizeof(n->mac));
1109         assert(s == sizeof(n->mac));
1110         qemu_format_nic_info_str(qemu_get_queue(n->nic), n->mac);
1111         rxfilter_notify(nc);
1112 
1113         return VIRTIO_NET_OK;
1114     }
1115 
1116     if (cmd != VIRTIO_NET_CTRL_MAC_TABLE_SET) {
1117         return VIRTIO_NET_ERR;
1118     }
1119 
1120     int in_use = 0;
1121     int first_multi = 0;
1122     uint8_t uni_overflow = 0;
1123     uint8_t multi_overflow = 0;
1124     uint8_t *macs = g_malloc0(MAC_TABLE_ENTRIES * ETH_ALEN);
1125 
1126     s = iov_to_buf(iov, iov_cnt, 0, &mac_data.entries,
1127                    sizeof(mac_data.entries));
1128     mac_data.entries = virtio_ldl_p(vdev, &mac_data.entries);
1129     if (s != sizeof(mac_data.entries)) {
1130         goto error;
1131     }
1132     iov_discard_front(&iov, &iov_cnt, s);
1133 
1134     if (mac_data.entries * ETH_ALEN > iov_size(iov, iov_cnt)) {
1135         goto error;
1136     }
1137 
1138     if (mac_data.entries <= MAC_TABLE_ENTRIES) {
1139         s = iov_to_buf(iov, iov_cnt, 0, macs,
1140                        mac_data.entries * ETH_ALEN);
1141         if (s != mac_data.entries * ETH_ALEN) {
1142             goto error;
1143         }
1144         in_use += mac_data.entries;
1145     } else {
1146         uni_overflow = 1;
1147     }
1148 
1149     iov_discard_front(&iov, &iov_cnt, mac_data.entries * ETH_ALEN);
1150 
1151     first_multi = in_use;
1152 
1153     s = iov_to_buf(iov, iov_cnt, 0, &mac_data.entries,
1154                    sizeof(mac_data.entries));
1155     mac_data.entries = virtio_ldl_p(vdev, &mac_data.entries);
1156     if (s != sizeof(mac_data.entries)) {
1157         goto error;
1158     }
1159 
1160     iov_discard_front(&iov, &iov_cnt, s);
1161 
1162     if (mac_data.entries * ETH_ALEN != iov_size(iov, iov_cnt)) {
1163         goto error;
1164     }
1165 
1166     if (mac_data.entries <= MAC_TABLE_ENTRIES - in_use) {
1167         s = iov_to_buf(iov, iov_cnt, 0, &macs[in_use * ETH_ALEN],
1168                        mac_data.entries * ETH_ALEN);
1169         if (s != mac_data.entries * ETH_ALEN) {
1170             goto error;
1171         }
1172         in_use += mac_data.entries;
1173     } else {
1174         multi_overflow = 1;
1175     }
1176 
1177     n->mac_table.in_use = in_use;
1178     n->mac_table.first_multi = first_multi;
1179     n->mac_table.uni_overflow = uni_overflow;
1180     n->mac_table.multi_overflow = multi_overflow;
1181     memcpy(n->mac_table.macs, macs, MAC_TABLE_ENTRIES * ETH_ALEN);
1182     g_free(macs);
1183     rxfilter_notify(nc);
1184 
1185     return VIRTIO_NET_OK;
1186 
1187 error:
1188     g_free(macs);
1189     return VIRTIO_NET_ERR;
1190 }
1191 
1192 static int virtio_net_handle_vlan_table(VirtIONet *n, uint8_t cmd,
1193                                         struct iovec *iov, unsigned int iov_cnt)
1194 {
1195     VirtIODevice *vdev = VIRTIO_DEVICE(n);
1196     uint16_t vid;
1197     size_t s;
1198     NetClientState *nc = qemu_get_queue(n->nic);
1199 
1200     s = iov_to_buf(iov, iov_cnt, 0, &vid, sizeof(vid));
1201     vid = virtio_lduw_p(vdev, &vid);
1202     if (s != sizeof(vid)) {
1203         return VIRTIO_NET_ERR;
1204     }
1205 
1206     if (vid >= MAX_VLAN)
1207         return VIRTIO_NET_ERR;
1208 
1209     if (cmd == VIRTIO_NET_CTRL_VLAN_ADD)
1210         n->vlans[vid >> 5] |= (1U << (vid & 0x1f));
1211     else if (cmd == VIRTIO_NET_CTRL_VLAN_DEL)
1212         n->vlans[vid >> 5] &= ~(1U << (vid & 0x1f));
1213     else
1214         return VIRTIO_NET_ERR;
1215 
1216     rxfilter_notify(nc);
1217 
1218     return VIRTIO_NET_OK;
1219 }
1220 
1221 static int virtio_net_handle_announce(VirtIONet *n, uint8_t cmd,
1222                                       struct iovec *iov, unsigned int iov_cnt)
1223 {
1224     trace_virtio_net_handle_announce(n->announce_timer.round);
1225     if (cmd == VIRTIO_NET_CTRL_ANNOUNCE_ACK &&
1226         n->status & VIRTIO_NET_S_ANNOUNCE) {
1227         n->status &= ~VIRTIO_NET_S_ANNOUNCE;
1228         if (n->announce_timer.round) {
1229             qemu_announce_timer_step(&n->announce_timer);
1230         }
1231         return VIRTIO_NET_OK;
1232     } else {
1233         return VIRTIO_NET_ERR;
1234     }
1235 }
1236 
1237 static bool virtio_net_attach_ebpf_to_backend(NICState *nic, int prog_fd)
1238 {
1239     NetClientState *nc = qemu_get_peer(qemu_get_queue(nic), 0);
1240     if (nc == NULL || nc->info->set_steering_ebpf == NULL) {
1241         return false;
1242     }
1243 
1244     trace_virtio_net_rss_attach_ebpf(nic, prog_fd);
1245     return nc->info->set_steering_ebpf(nc, prog_fd);
1246 }
1247 
1248 static void rss_data_to_rss_config(struct VirtioNetRssData *data,
1249                                    struct EBPFRSSConfig *config)
1250 {
1251     config->redirect = data->redirect;
1252     config->populate_hash = data->populate_hash;
1253     config->hash_types = data->hash_types;
1254     config->indirections_len = data->indirections_len;
1255     config->default_queue = data->default_queue;
1256 }
1257 
1258 static bool virtio_net_attach_ebpf_rss(VirtIONet *n)
1259 {
1260     struct EBPFRSSConfig config = {};
1261 
1262     if (!ebpf_rss_is_loaded(&n->ebpf_rss)) {
1263         return false;
1264     }
1265 
1266     rss_data_to_rss_config(&n->rss_data, &config);
1267 
1268     if (!ebpf_rss_set_all(&n->ebpf_rss, &config,
1269                           n->rss_data.indirections_table, n->rss_data.key,
1270                           NULL)) {
1271         return false;
1272     }
1273 
1274     if (!virtio_net_attach_ebpf_to_backend(n->nic, n->ebpf_rss.program_fd)) {
1275         return false;
1276     }
1277 
1278     return true;
1279 }
1280 
1281 static void virtio_net_detach_ebpf_rss(VirtIONet *n)
1282 {
1283     virtio_net_attach_ebpf_to_backend(n->nic, -1);
1284 }
1285 
1286 static void virtio_net_commit_rss_config(VirtIONet *n)
1287 {
1288     if (n->rss_data.enabled) {
1289         n->rss_data.enabled_software_rss = n->rss_data.populate_hash;
1290         if (n->rss_data.populate_hash) {
1291             virtio_net_detach_ebpf_rss(n);
1292         } else if (!virtio_net_attach_ebpf_rss(n)) {
1293             if (get_vhost_net(qemu_get_queue(n->nic)->peer)) {
1294                 warn_report("Can't load eBPF RSS for vhost");
1295             } else {
1296                 warn_report("Can't load eBPF RSS - fallback to software RSS");
1297                 n->rss_data.enabled_software_rss = true;
1298             }
1299         }
1300 
1301         trace_virtio_net_rss_enable(n,
1302                                     n->rss_data.hash_types,
1303                                     n->rss_data.indirections_len,
1304                                     sizeof(n->rss_data.key));
1305     } else {
1306         virtio_net_detach_ebpf_rss(n);
1307         trace_virtio_net_rss_disable(n);
1308     }
1309 }
1310 
1311 static void virtio_net_disable_rss(VirtIONet *n)
1312 {
1313     if (!n->rss_data.enabled) {
1314         return;
1315     }
1316 
1317     n->rss_data.enabled = false;
1318     virtio_net_commit_rss_config(n);
1319 }
1320 
1321 static bool virtio_net_load_ebpf_fds(VirtIONet *n, Error **errp)
1322 {
1323     int fds[EBPF_RSS_MAX_FDS] = { [0 ... EBPF_RSS_MAX_FDS - 1] = -1};
1324     int ret = true;
1325     int i = 0;
1326 
1327     if (n->nr_ebpf_rss_fds != EBPF_RSS_MAX_FDS) {
1328         error_setg(errp, "Expected %d file descriptors but got %d",
1329                    EBPF_RSS_MAX_FDS, n->nr_ebpf_rss_fds);
1330         return false;
1331     }
1332 
1333     for (i = 0; i < n->nr_ebpf_rss_fds; i++) {
1334         fds[i] = monitor_fd_param(monitor_cur(), n->ebpf_rss_fds[i], errp);
1335         if (fds[i] < 0) {
1336             ret = false;
1337             goto exit;
1338         }
1339     }
1340 
1341     ret = ebpf_rss_load_fds(&n->ebpf_rss, fds[0], fds[1], fds[2], fds[3], errp);
1342 
1343 exit:
1344     if (!ret) {
1345         for (i = 0; i < n->nr_ebpf_rss_fds && fds[i] != -1; i++) {
1346             close(fds[i]);
1347         }
1348     }
1349 
1350     return ret;
1351 }
1352 
1353 static bool virtio_net_load_ebpf(VirtIONet *n, Error **errp)
1354 {
1355     bool ret = false;
1356 
1357     if (virtio_net_attach_ebpf_to_backend(n->nic, -1)) {
1358         trace_virtio_net_rss_load(n, n->nr_ebpf_rss_fds, n->ebpf_rss_fds);
1359         if (n->ebpf_rss_fds) {
1360             ret = virtio_net_load_ebpf_fds(n, errp);
1361         } else {
1362             ret = ebpf_rss_load(&n->ebpf_rss, errp);
1363         }
1364     }
1365 
1366     return ret;
1367 }
1368 
1369 static void virtio_net_unload_ebpf(VirtIONet *n)
1370 {
1371     virtio_net_attach_ebpf_to_backend(n->nic, -1);
1372     ebpf_rss_unload(&n->ebpf_rss);
1373 }
1374 
1375 static uint16_t virtio_net_handle_rss(VirtIONet *n,
1376                                       struct iovec *iov,
1377                                       unsigned int iov_cnt,
1378                                       bool do_rss)
1379 {
1380     VirtIODevice *vdev = VIRTIO_DEVICE(n);
1381     struct virtio_net_rss_config cfg;
1382     size_t s, offset = 0, size_get;
1383     uint16_t queue_pairs, i;
1384     struct {
1385         uint16_t us;
1386         uint8_t b;
1387     } QEMU_PACKED temp;
1388     const char *err_msg = "";
1389     uint32_t err_value = 0;
1390 
1391     if (do_rss && !virtio_vdev_has_feature(vdev, VIRTIO_NET_F_RSS)) {
1392         err_msg = "RSS is not negotiated";
1393         goto error;
1394     }
1395     if (!do_rss && !virtio_vdev_has_feature(vdev, VIRTIO_NET_F_HASH_REPORT)) {
1396         err_msg = "Hash report is not negotiated";
1397         goto error;
1398     }
1399     size_get = offsetof(struct virtio_net_rss_config, indirection_table);
1400     s = iov_to_buf(iov, iov_cnt, offset, &cfg, size_get);
1401     if (s != size_get) {
1402         err_msg = "Short command buffer";
1403         err_value = (uint32_t)s;
1404         goto error;
1405     }
1406     n->rss_data.hash_types = virtio_ldl_p(vdev, &cfg.hash_types);
1407     n->rss_data.indirections_len =
1408         virtio_lduw_p(vdev, &cfg.indirection_table_mask);
1409     if (!do_rss) {
1410         n->rss_data.indirections_len = 0;
1411     }
1412     if (n->rss_data.indirections_len >= VIRTIO_NET_RSS_MAX_TABLE_LEN) {
1413         err_msg = "Too large indirection table";
1414         err_value = n->rss_data.indirections_len;
1415         goto error;
1416     }
1417     n->rss_data.indirections_len++;
1418     if (!is_power_of_2(n->rss_data.indirections_len)) {
1419         err_msg = "Invalid size of indirection table";
1420         err_value = n->rss_data.indirections_len;
1421         goto error;
1422     }
1423     n->rss_data.default_queue = do_rss ?
1424         virtio_lduw_p(vdev, &cfg.unclassified_queue) : 0;
1425     if (n->rss_data.default_queue >= n->max_queue_pairs) {
1426         err_msg = "Invalid default queue";
1427         err_value = n->rss_data.default_queue;
1428         goto error;
1429     }
1430     offset += size_get;
1431     size_get = sizeof(uint16_t) * n->rss_data.indirections_len;
1432     g_free(n->rss_data.indirections_table);
1433     n->rss_data.indirections_table = g_malloc(size_get);
1434     if (!n->rss_data.indirections_table) {
1435         err_msg = "Can't allocate indirections table";
1436         err_value = n->rss_data.indirections_len;
1437         goto error;
1438     }
1439     s = iov_to_buf(iov, iov_cnt, offset,
1440                    n->rss_data.indirections_table, size_get);
1441     if (s != size_get) {
1442         err_msg = "Short indirection table buffer";
1443         err_value = (uint32_t)s;
1444         goto error;
1445     }
1446     for (i = 0; i < n->rss_data.indirections_len; ++i) {
1447         uint16_t val = n->rss_data.indirections_table[i];
1448         n->rss_data.indirections_table[i] = virtio_lduw_p(vdev, &val);
1449     }
1450     offset += size_get;
1451     size_get = sizeof(temp);
1452     s = iov_to_buf(iov, iov_cnt, offset, &temp, size_get);
1453     if (s != size_get) {
1454         err_msg = "Can't get queue_pairs";
1455         err_value = (uint32_t)s;
1456         goto error;
1457     }
1458     queue_pairs = do_rss ? virtio_lduw_p(vdev, &temp.us) : n->curr_queue_pairs;
1459     if (queue_pairs == 0 || queue_pairs > n->max_queue_pairs) {
1460         err_msg = "Invalid number of queue_pairs";
1461         err_value = queue_pairs;
1462         goto error;
1463     }
1464     if (temp.b > VIRTIO_NET_RSS_MAX_KEY_SIZE) {
1465         err_msg = "Invalid key size";
1466         err_value = temp.b;
1467         goto error;
1468     }
1469     if (!temp.b && n->rss_data.hash_types) {
1470         err_msg = "No key provided";
1471         err_value = 0;
1472         goto error;
1473     }
1474     if (!temp.b && !n->rss_data.hash_types) {
1475         virtio_net_disable_rss(n);
1476         return queue_pairs;
1477     }
1478     offset += size_get;
1479     size_get = temp.b;
1480     s = iov_to_buf(iov, iov_cnt, offset, n->rss_data.key, size_get);
1481     if (s != size_get) {
1482         err_msg = "Can get key buffer";
1483         err_value = (uint32_t)s;
1484         goto error;
1485     }
1486     n->rss_data.enabled = true;
1487     virtio_net_commit_rss_config(n);
1488     return queue_pairs;
1489 error:
1490     trace_virtio_net_rss_error(n, err_msg, err_value);
1491     virtio_net_disable_rss(n);
1492     return 0;
1493 }
1494 
1495 static int virtio_net_handle_mq(VirtIONet *n, uint8_t cmd,
1496                                 struct iovec *iov, unsigned int iov_cnt)
1497 {
1498     VirtIODevice *vdev = VIRTIO_DEVICE(n);
1499     uint16_t queue_pairs;
1500     NetClientState *nc = qemu_get_queue(n->nic);
1501 
1502     virtio_net_disable_rss(n);
1503     if (cmd == VIRTIO_NET_CTRL_MQ_HASH_CONFIG) {
1504         queue_pairs = virtio_net_handle_rss(n, iov, iov_cnt, false);
1505         return queue_pairs ? VIRTIO_NET_OK : VIRTIO_NET_ERR;
1506     }
1507     if (cmd == VIRTIO_NET_CTRL_MQ_RSS_CONFIG) {
1508         queue_pairs = virtio_net_handle_rss(n, iov, iov_cnt, true);
1509     } else if (cmd == VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET) {
1510         struct virtio_net_ctrl_mq mq;
1511         size_t s;
1512         if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_MQ)) {
1513             return VIRTIO_NET_ERR;
1514         }
1515         s = iov_to_buf(iov, iov_cnt, 0, &mq, sizeof(mq));
1516         if (s != sizeof(mq)) {
1517             return VIRTIO_NET_ERR;
1518         }
1519         queue_pairs = virtio_lduw_p(vdev, &mq.virtqueue_pairs);
1520 
1521     } else {
1522         return VIRTIO_NET_ERR;
1523     }
1524 
1525     if (queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
1526         queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
1527         queue_pairs > n->max_queue_pairs ||
1528         !n->multiqueue) {
1529         return VIRTIO_NET_ERR;
1530     }
1531 
1532     n->curr_queue_pairs = queue_pairs;
1533     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_VDPA) {
1534         /*
1535          * Avoid updating the backend for a vdpa device: We're only interested
1536          * in updating the device model queues.
1537          */
1538         return VIRTIO_NET_OK;
1539     }
1540     /* stop the backend before changing the number of queue_pairs to avoid handling a
1541      * disabled queue */
1542     virtio_net_set_status(vdev, vdev->status);
1543     virtio_net_set_queue_pairs(n);
1544 
1545     return VIRTIO_NET_OK;
1546 }
1547 
1548 size_t virtio_net_handle_ctrl_iov(VirtIODevice *vdev,
1549                                   const struct iovec *in_sg, unsigned in_num,
1550                                   const struct iovec *out_sg,
1551                                   unsigned out_num)
1552 {
1553     VirtIONet *n = VIRTIO_NET(vdev);
1554     struct virtio_net_ctrl_hdr ctrl;
1555     virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
1556     size_t s;
1557     struct iovec *iov, *iov2;
1558 
1559     if (iov_size(in_sg, in_num) < sizeof(status) ||
1560         iov_size(out_sg, out_num) < sizeof(ctrl)) {
1561         virtio_error(vdev, "virtio-net ctrl missing headers");
1562         return 0;
1563     }
1564 
1565     iov2 = iov = g_memdup2(out_sg, sizeof(struct iovec) * out_num);
1566     s = iov_to_buf(iov, out_num, 0, &ctrl, sizeof(ctrl));
1567     iov_discard_front(&iov, &out_num, sizeof(ctrl));
1568     if (s != sizeof(ctrl)) {
1569         status = VIRTIO_NET_ERR;
1570     } else if (ctrl.class == VIRTIO_NET_CTRL_RX) {
1571         status = virtio_net_handle_rx_mode(n, ctrl.cmd, iov, out_num);
1572     } else if (ctrl.class == VIRTIO_NET_CTRL_MAC) {
1573         status = virtio_net_handle_mac(n, ctrl.cmd, iov, out_num);
1574     } else if (ctrl.class == VIRTIO_NET_CTRL_VLAN) {
1575         status = virtio_net_handle_vlan_table(n, ctrl.cmd, iov, out_num);
1576     } else if (ctrl.class == VIRTIO_NET_CTRL_ANNOUNCE) {
1577         status = virtio_net_handle_announce(n, ctrl.cmd, iov, out_num);
1578     } else if (ctrl.class == VIRTIO_NET_CTRL_MQ) {
1579         status = virtio_net_handle_mq(n, ctrl.cmd, iov, out_num);
1580     } else if (ctrl.class == VIRTIO_NET_CTRL_GUEST_OFFLOADS) {
1581         status = virtio_net_handle_offloads(n, ctrl.cmd, iov, out_num);
1582     }
1583 
1584     s = iov_from_buf(in_sg, in_num, 0, &status, sizeof(status));
1585     assert(s == sizeof(status));
1586 
1587     g_free(iov2);
1588     return sizeof(status);
1589 }
1590 
1591 static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
1592 {
1593     VirtQueueElement *elem;
1594 
1595     for (;;) {
1596         size_t written;
1597         elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
1598         if (!elem) {
1599             break;
1600         }
1601 
1602         written = virtio_net_handle_ctrl_iov(vdev, elem->in_sg, elem->in_num,
1603                                              elem->out_sg, elem->out_num);
1604         if (written > 0) {
1605             virtqueue_push(vq, elem, written);
1606             virtio_notify(vdev, vq);
1607             g_free(elem);
1608         } else {
1609             virtqueue_detach_element(vq, elem, 0);
1610             g_free(elem);
1611             break;
1612         }
1613     }
1614 }
1615 
1616 /* RX */
1617 
1618 static void virtio_net_handle_rx(VirtIODevice *vdev, VirtQueue *vq)
1619 {
1620     VirtIONet *n = VIRTIO_NET(vdev);
1621     int queue_index = vq2q(virtio_get_queue_index(vq));
1622 
1623     qemu_flush_queued_packets(qemu_get_subqueue(n->nic, queue_index));
1624 }
1625 
1626 static bool virtio_net_can_receive(NetClientState *nc)
1627 {
1628     VirtIONet *n = qemu_get_nic_opaque(nc);
1629     VirtIODevice *vdev = VIRTIO_DEVICE(n);
1630     VirtIONetQueue *q = virtio_net_get_subqueue(nc);
1631 
1632     if (!vdev->vm_running) {
1633         return false;
1634     }
1635 
1636     if (nc->queue_index >= n->curr_queue_pairs) {
1637         return false;
1638     }
1639 
1640     if (!virtio_queue_ready(q->rx_vq) ||
1641         !(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
1642         return false;
1643     }
1644 
1645     return true;
1646 }
1647 
1648 static int virtio_net_has_buffers(VirtIONetQueue *q, int bufsize)
1649 {
1650     int opaque;
1651     unsigned int in_bytes;
1652     VirtIONet *n = q->n;
1653 
1654     while (virtio_queue_empty(q->rx_vq) || n->mergeable_rx_bufs) {
1655         opaque = virtqueue_get_avail_bytes(q->rx_vq, &in_bytes, NULL,
1656                                            bufsize, 0);
1657         /* Buffer is enough, disable notifiaction */
1658         if (bufsize <= in_bytes) {
1659             break;
1660         }
1661 
1662         if (virtio_queue_enable_notification_and_check(q->rx_vq, opaque)) {
1663             /* Guest has added some buffers, try again */
1664             continue;
1665         } else {
1666             return 0;
1667         }
1668     }
1669 
1670     virtio_queue_set_notification(q->rx_vq, 0);
1671 
1672     return 1;
1673 }
1674 
1675 static void virtio_net_hdr_swap(VirtIODevice *vdev, struct virtio_net_hdr *hdr)
1676 {
1677     virtio_tswap16s(vdev, &hdr->hdr_len);
1678     virtio_tswap16s(vdev, &hdr->gso_size);
1679     virtio_tswap16s(vdev, &hdr->csum_start);
1680     virtio_tswap16s(vdev, &hdr->csum_offset);
1681 }
1682 
1683 /* dhclient uses AF_PACKET but doesn't pass auxdata to the kernel so
1684  * it never finds out that the packets don't have valid checksums.  This
1685  * causes dhclient to get upset.  Fedora's carried a patch for ages to
1686  * fix this with Xen but it hasn't appeared in an upstream release of
1687  * dhclient yet.
1688  *
1689  * To avoid breaking existing guests, we catch udp packets and add
1690  * checksums.  This is terrible but it's better than hacking the guest
1691  * kernels.
1692  *
1693  * N.B. if we introduce a zero-copy API, this operation is no longer free so
1694  * we should provide a mechanism to disable it to avoid polluting the host
1695  * cache.
1696  */
1697 static void work_around_broken_dhclient(struct virtio_net_hdr *hdr,
1698                                         size_t *hdr_len, const uint8_t *buf,
1699                                         size_t buf_size, size_t *buf_offset)
1700 {
1701     size_t csum_size = ETH_HLEN + sizeof(struct ip_header) +
1702                        sizeof(struct udp_header);
1703 
1704     buf += *buf_offset;
1705     buf_size -= *buf_offset;
1706 
1707     if ((hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && /* missing csum */
1708         (buf_size >= csum_size && buf_size < 1500) && /* normal sized MTU */
1709         (buf[12] == 0x08 && buf[13] == 0x00) && /* ethertype == IPv4 */
1710         (buf[23] == 17) && /* ip.protocol == UDP */
1711         (buf[34] == 0 && buf[35] == 67)) { /* udp.srcport == bootps */
1712         memcpy((uint8_t *)hdr + *hdr_len, buf, csum_size);
1713         net_checksum_calculate((uint8_t *)hdr + *hdr_len, csum_size, CSUM_UDP);
1714         hdr->flags &= ~VIRTIO_NET_HDR_F_NEEDS_CSUM;
1715         *hdr_len += csum_size;
1716         *buf_offset += csum_size;
1717     }
1718 }
1719 
1720 static size_t receive_header(VirtIONet *n, struct virtio_net_hdr *hdr,
1721                              const void *buf, size_t buf_size,
1722                              size_t *buf_offset)
1723 {
1724     size_t hdr_len = n->guest_hdr_len;
1725 
1726     memcpy(hdr, buf, sizeof(struct virtio_net_hdr));
1727 
1728     *buf_offset = n->host_hdr_len;
1729     work_around_broken_dhclient(hdr, &hdr_len, buf, buf_size, buf_offset);
1730 
1731     if (n->needs_vnet_hdr_swap) {
1732         virtio_net_hdr_swap(VIRTIO_DEVICE(n), hdr);
1733     }
1734 
1735     return hdr_len;
1736 }
1737 
1738 static int receive_filter(VirtIONet *n, const uint8_t *buf, int size)
1739 {
1740     static const uint8_t bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
1741     static const uint8_t vlan[] = {0x81, 0x00};
1742     uint8_t *ptr = (uint8_t *)buf;
1743     int i;
1744 
1745     if (n->promisc)
1746         return 1;
1747 
1748     ptr += n->host_hdr_len;
1749 
1750     if (!memcmp(&ptr[12], vlan, sizeof(vlan))) {
1751         int vid = lduw_be_p(ptr + 14) & 0xfff;
1752         if (!(n->vlans[vid >> 5] & (1U << (vid & 0x1f))))
1753             return 0;
1754     }
1755 
1756     if (ptr[0] & 1) { // multicast
1757         if (!memcmp(ptr, bcast, sizeof(bcast))) {
1758             return !n->nobcast;
1759         } else if (n->nomulti) {
1760             return 0;
1761         } else if (n->allmulti || n->mac_table.multi_overflow) {
1762             return 1;
1763         }
1764 
1765         for (i = n->mac_table.first_multi; i < n->mac_table.in_use; i++) {
1766             if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN)) {
1767                 return 1;
1768             }
1769         }
1770     } else { // unicast
1771         if (n->nouni) {
1772             return 0;
1773         } else if (n->alluni || n->mac_table.uni_overflow) {
1774             return 1;
1775         } else if (!memcmp(ptr, n->mac, ETH_ALEN)) {
1776             return 1;
1777         }
1778 
1779         for (i = 0; i < n->mac_table.first_multi; i++) {
1780             if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN)) {
1781                 return 1;
1782             }
1783         }
1784     }
1785 
1786     return 0;
1787 }
1788 
1789 static uint8_t virtio_net_get_hash_type(bool hasip4,
1790                                         bool hasip6,
1791                                         EthL4HdrProto l4hdr_proto,
1792                                         uint32_t types)
1793 {
1794     if (hasip4) {
1795         switch (l4hdr_proto) {
1796         case ETH_L4_HDR_PROTO_TCP:
1797             if (types & VIRTIO_NET_RSS_HASH_TYPE_TCPv4) {
1798                 return NetPktRssIpV4Tcp;
1799             }
1800             break;
1801 
1802         case ETH_L4_HDR_PROTO_UDP:
1803             if (types & VIRTIO_NET_RSS_HASH_TYPE_UDPv4) {
1804                 return NetPktRssIpV4Udp;
1805             }
1806             break;
1807 
1808         default:
1809             break;
1810         }
1811 
1812         if (types & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
1813             return NetPktRssIpV4;
1814         }
1815     } else if (hasip6) {
1816         switch (l4hdr_proto) {
1817         case ETH_L4_HDR_PROTO_TCP:
1818             if (types & VIRTIO_NET_RSS_HASH_TYPE_TCP_EX) {
1819                 return NetPktRssIpV6TcpEx;
1820             }
1821             if (types & VIRTIO_NET_RSS_HASH_TYPE_TCPv6) {
1822                 return NetPktRssIpV6Tcp;
1823             }
1824             break;
1825 
1826         case ETH_L4_HDR_PROTO_UDP:
1827             if (types & VIRTIO_NET_RSS_HASH_TYPE_UDP_EX) {
1828                 return NetPktRssIpV6UdpEx;
1829             }
1830             if (types & VIRTIO_NET_RSS_HASH_TYPE_UDPv6) {
1831                 return NetPktRssIpV6Udp;
1832             }
1833             break;
1834 
1835         default:
1836             break;
1837         }
1838 
1839         if (types & VIRTIO_NET_RSS_HASH_TYPE_IP_EX) {
1840             return NetPktRssIpV6Ex;
1841         }
1842         if (types & VIRTIO_NET_RSS_HASH_TYPE_IPv6) {
1843             return NetPktRssIpV6;
1844         }
1845     }
1846     return 0xff;
1847 }
1848 
1849 static int virtio_net_process_rss(NetClientState *nc, const uint8_t *buf,
1850                                   size_t size,
1851                                   struct virtio_net_hdr_v1_hash *hdr)
1852 {
1853     VirtIONet *n = qemu_get_nic_opaque(nc);
1854     unsigned int index = nc->queue_index, new_index = index;
1855     struct NetRxPkt *pkt = n->rx_pkt;
1856     uint8_t net_hash_type;
1857     uint32_t hash;
1858     bool hasip4, hasip6;
1859     EthL4HdrProto l4hdr_proto;
1860     static const uint8_t reports[NetPktRssIpV6UdpEx + 1] = {
1861         VIRTIO_NET_HASH_REPORT_IPv4,
1862         VIRTIO_NET_HASH_REPORT_TCPv4,
1863         VIRTIO_NET_HASH_REPORT_TCPv6,
1864         VIRTIO_NET_HASH_REPORT_IPv6,
1865         VIRTIO_NET_HASH_REPORT_IPv6_EX,
1866         VIRTIO_NET_HASH_REPORT_TCPv6_EX,
1867         VIRTIO_NET_HASH_REPORT_UDPv4,
1868         VIRTIO_NET_HASH_REPORT_UDPv6,
1869         VIRTIO_NET_HASH_REPORT_UDPv6_EX
1870     };
1871     struct iovec iov = {
1872         .iov_base = (void *)buf,
1873         .iov_len = size
1874     };
1875 
1876     net_rx_pkt_set_protocols(pkt, &iov, 1, n->host_hdr_len);
1877     net_rx_pkt_get_protocols(pkt, &hasip4, &hasip6, &l4hdr_proto);
1878     net_hash_type = virtio_net_get_hash_type(hasip4, hasip6, l4hdr_proto,
1879                                              n->rss_data.hash_types);
1880     if (net_hash_type > NetPktRssIpV6UdpEx) {
1881         if (n->rss_data.populate_hash) {
1882             hdr->hash_value = VIRTIO_NET_HASH_REPORT_NONE;
1883             hdr->hash_report = 0;
1884         }
1885         return n->rss_data.redirect ? n->rss_data.default_queue : -1;
1886     }
1887 
1888     hash = net_rx_pkt_calc_rss_hash(pkt, net_hash_type, n->rss_data.key);
1889 
1890     if (n->rss_data.populate_hash) {
1891         hdr->hash_value = hash;
1892         hdr->hash_report = reports[net_hash_type];
1893     }
1894 
1895     if (n->rss_data.redirect) {
1896         new_index = hash & (n->rss_data.indirections_len - 1);
1897         new_index = n->rss_data.indirections_table[new_index];
1898     }
1899 
1900     return (index == new_index) ? -1 : new_index;
1901 }
1902 
1903 typedef struct Header {
1904     struct virtio_net_hdr_v1_hash virtio_net;
1905     struct eth_header eth;
1906     struct ip_header ip;
1907     struct udp_header udp;
1908 } Header;
1909 
1910 static ssize_t virtio_net_receive_rcu(NetClientState *nc, const uint8_t *buf,
1911                                       size_t size)
1912 {
1913     VirtIONet *n = qemu_get_nic_opaque(nc);
1914     VirtIONetQueue *q;
1915     VirtIODevice *vdev = VIRTIO_DEVICE(n);
1916     VirtQueueElement *elems[VIRTQUEUE_MAX_SIZE];
1917     size_t lens[VIRTQUEUE_MAX_SIZE];
1918     struct iovec mhdr_sg[VIRTQUEUE_MAX_SIZE];
1919     Header hdr;
1920     unsigned mhdr_cnt = 0;
1921     size_t offset, i, guest_offset, j;
1922     ssize_t err;
1923 
1924     memset(&hdr.virtio_net, 0, sizeof(hdr.virtio_net));
1925 
1926     if (n->rss_data.enabled && n->rss_data.enabled_software_rss) {
1927         int index = virtio_net_process_rss(nc, buf, size, &hdr.virtio_net);
1928         if (index >= 0) {
1929             nc = qemu_get_subqueue(n->nic, index % n->curr_queue_pairs);
1930         }
1931     }
1932 
1933     if (!virtio_net_can_receive(nc)) {
1934         return -1;
1935     }
1936 
1937     q = virtio_net_get_subqueue(nc);
1938 
1939     /* hdr_len refers to the header we supply to the guest */
1940     if (!virtio_net_has_buffers(q, size + n->guest_hdr_len - n->host_hdr_len)) {
1941         return 0;
1942     }
1943 
1944     if (!receive_filter(n, buf, size))
1945         return size;
1946 
1947     offset = i = 0;
1948 
1949     while (offset < size) {
1950         VirtQueueElement *elem;
1951         int len, total;
1952         const struct iovec *sg;
1953 
1954         total = 0;
1955 
1956         if (i == VIRTQUEUE_MAX_SIZE) {
1957             virtio_error(vdev, "virtio-net unexpected long buffer chain");
1958             err = size;
1959             goto err;
1960         }
1961 
1962         elem = virtqueue_pop(q->rx_vq, sizeof(VirtQueueElement));
1963         if (!elem) {
1964             if (i) {
1965                 virtio_error(vdev, "virtio-net unexpected empty queue: "
1966                              "i %zd mergeable %d offset %zd, size %zd, "
1967                              "guest hdr len %zd, host hdr len %zd "
1968                              "guest features 0x%" PRIx64,
1969                              i, n->mergeable_rx_bufs, offset, size,
1970                              n->guest_hdr_len, n->host_hdr_len,
1971                              vdev->guest_features);
1972             }
1973             err = -1;
1974             goto err;
1975         }
1976 
1977         if (elem->in_num < 1) {
1978             virtio_error(vdev,
1979                          "virtio-net receive queue contains no in buffers");
1980             virtqueue_detach_element(q->rx_vq, elem, 0);
1981             g_free(elem);
1982             err = -1;
1983             goto err;
1984         }
1985 
1986         sg = elem->in_sg;
1987         if (i == 0) {
1988             assert(offset == 0);
1989             if (n->mergeable_rx_bufs) {
1990                 mhdr_cnt = iov_copy(mhdr_sg, ARRAY_SIZE(mhdr_sg),
1991                                     sg, elem->in_num,
1992                                     offsetof(typeof(hdr),
1993                                              virtio_net.hdr.num_buffers),
1994                                     sizeof(hdr.virtio_net.hdr.num_buffers));
1995             }
1996 
1997             guest_offset = n->has_vnet_hdr ?
1998                            receive_header(n, (struct virtio_net_hdr *)&hdr,
1999                                           buf, size, &offset) :
2000                            n->guest_hdr_len;
2001 
2002             iov_from_buf(sg, elem->in_num, 0, &hdr, guest_offset);
2003             total += guest_offset;
2004         } else {
2005             guest_offset = 0;
2006         }
2007 
2008         /* copy in packet.  ugh */
2009         len = iov_from_buf(sg, elem->in_num, guest_offset,
2010                            buf + offset, size - offset);
2011         total += len;
2012         offset += len;
2013         /* If buffers can't be merged, at this point we
2014          * must have consumed the complete packet.
2015          * Otherwise, drop it. */
2016         if (!n->mergeable_rx_bufs && offset < size) {
2017             virtqueue_unpop(q->rx_vq, elem, total);
2018             g_free(elem);
2019             err = size;
2020             goto err;
2021         }
2022 
2023         elems[i] = elem;
2024         lens[i] = total;
2025         i++;
2026     }
2027 
2028     if (mhdr_cnt) {
2029         virtio_stw_p(vdev, &hdr.virtio_net.hdr.num_buffers, i);
2030         iov_from_buf(mhdr_sg, mhdr_cnt,
2031                      0,
2032                      &hdr.virtio_net.hdr.num_buffers,
2033                      sizeof hdr.virtio_net.hdr.num_buffers);
2034     }
2035 
2036     for (j = 0; j < i; j++) {
2037         /* signal other side */
2038         virtqueue_fill(q->rx_vq, elems[j], lens[j], j);
2039         g_free(elems[j]);
2040     }
2041 
2042     virtqueue_flush(q->rx_vq, i);
2043     virtio_notify(vdev, q->rx_vq);
2044 
2045     return size;
2046 
2047 err:
2048     for (j = 0; j < i; j++) {
2049         virtqueue_detach_element(q->rx_vq, elems[j], lens[j]);
2050         g_free(elems[j]);
2051     }
2052 
2053     return err;
2054 }
2055 
2056 static ssize_t virtio_net_do_receive(NetClientState *nc, const uint8_t *buf,
2057                                   size_t size)
2058 {
2059     RCU_READ_LOCK_GUARD();
2060 
2061     return virtio_net_receive_rcu(nc, buf, size);
2062 }
2063 
2064 /*
2065  * Accessors to read and write the IP packet data length field. This
2066  * is a potentially unaligned network-byte-order 16 bit unsigned integer
2067  * pointed to by unit->ip_len.
2068  */
2069 static uint16_t read_unit_ip_len(VirtioNetRscUnit *unit)
2070 {
2071     return lduw_be_p(unit->ip_plen);
2072 }
2073 
2074 static void write_unit_ip_len(VirtioNetRscUnit *unit, uint16_t l)
2075 {
2076     stw_be_p(unit->ip_plen, l);
2077 }
2078 
2079 static void virtio_net_rsc_extract_unit4(VirtioNetRscChain *chain,
2080                                          const uint8_t *buf,
2081                                          VirtioNetRscUnit *unit)
2082 {
2083     uint16_t ip_hdrlen;
2084     struct ip_header *ip;
2085 
2086     ip = (struct ip_header *)(buf + chain->n->guest_hdr_len
2087                               + sizeof(struct eth_header));
2088     unit->ip = (void *)ip;
2089     ip_hdrlen = (ip->ip_ver_len & 0xF) << 2;
2090     unit->ip_plen = &ip->ip_len;
2091     unit->tcp = (struct tcp_header *)(((uint8_t *)unit->ip) + ip_hdrlen);
2092     unit->tcp_hdrlen = (htons(unit->tcp->th_offset_flags) & 0xF000) >> 10;
2093     unit->payload = read_unit_ip_len(unit) - ip_hdrlen - unit->tcp_hdrlen;
2094 }
2095 
2096 static void virtio_net_rsc_extract_unit6(VirtioNetRscChain *chain,
2097                                          const uint8_t *buf,
2098                                          VirtioNetRscUnit *unit)
2099 {
2100     struct ip6_header *ip6;
2101 
2102     ip6 = (struct ip6_header *)(buf + chain->n->guest_hdr_len
2103                                  + sizeof(struct eth_header));
2104     unit->ip = ip6;
2105     unit->ip_plen = &(ip6->ip6_ctlun.ip6_un1.ip6_un1_plen);
2106     unit->tcp = (struct tcp_header *)(((uint8_t *)unit->ip)
2107                                         + sizeof(struct ip6_header));
2108     unit->tcp_hdrlen = (htons(unit->tcp->th_offset_flags) & 0xF000) >> 10;
2109 
2110     /* There is a difference between payload length in ipv4 and v6,
2111        ip header is excluded in ipv6 */
2112     unit->payload = read_unit_ip_len(unit) - unit->tcp_hdrlen;
2113 }
2114 
2115 static size_t virtio_net_rsc_drain_seg(VirtioNetRscChain *chain,
2116                                        VirtioNetRscSeg *seg)
2117 {
2118     int ret;
2119     struct virtio_net_hdr_v1 *h;
2120 
2121     h = (struct virtio_net_hdr_v1 *)seg->buf;
2122     h->flags = 0;
2123     h->gso_type = VIRTIO_NET_HDR_GSO_NONE;
2124 
2125     if (seg->is_coalesced) {
2126         h->rsc.segments = seg->packets;
2127         h->rsc.dup_acks = seg->dup_ack;
2128         h->flags = VIRTIO_NET_HDR_F_RSC_INFO;
2129         if (chain->proto == ETH_P_IP) {
2130             h->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
2131         } else {
2132             h->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
2133         }
2134     }
2135 
2136     ret = virtio_net_do_receive(seg->nc, seg->buf, seg->size);
2137     QTAILQ_REMOVE(&chain->buffers, seg, next);
2138     g_free(seg->buf);
2139     g_free(seg);
2140 
2141     return ret;
2142 }
2143 
2144 static void virtio_net_rsc_purge(void *opq)
2145 {
2146     VirtioNetRscSeg *seg, *rn;
2147     VirtioNetRscChain *chain = (VirtioNetRscChain *)opq;
2148 
2149     QTAILQ_FOREACH_SAFE(seg, &chain->buffers, next, rn) {
2150         if (virtio_net_rsc_drain_seg(chain, seg) == 0) {
2151             chain->stat.purge_failed++;
2152             continue;
2153         }
2154     }
2155 
2156     chain->stat.timer++;
2157     if (!QTAILQ_EMPTY(&chain->buffers)) {
2158         timer_mod(chain->drain_timer,
2159               qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + chain->n->rsc_timeout);
2160     }
2161 }
2162 
2163 static void virtio_net_rsc_cleanup(VirtIONet *n)
2164 {
2165     VirtioNetRscChain *chain, *rn_chain;
2166     VirtioNetRscSeg *seg, *rn_seg;
2167 
2168     QTAILQ_FOREACH_SAFE(chain, &n->rsc_chains, next, rn_chain) {
2169         QTAILQ_FOREACH_SAFE(seg, &chain->buffers, next, rn_seg) {
2170             QTAILQ_REMOVE(&chain->buffers, seg, next);
2171             g_free(seg->buf);
2172             g_free(seg);
2173         }
2174 
2175         timer_free(chain->drain_timer);
2176         QTAILQ_REMOVE(&n->rsc_chains, chain, next);
2177         g_free(chain);
2178     }
2179 }
2180 
2181 static void virtio_net_rsc_cache_buf(VirtioNetRscChain *chain,
2182                                      NetClientState *nc,
2183                                      const uint8_t *buf, size_t size)
2184 {
2185     uint16_t hdr_len;
2186     VirtioNetRscSeg *seg;
2187 
2188     hdr_len = chain->n->guest_hdr_len;
2189     seg = g_new(VirtioNetRscSeg, 1);
2190     seg->buf = g_malloc(hdr_len + sizeof(struct eth_header)
2191         + sizeof(struct ip6_header) + VIRTIO_NET_MAX_TCP_PAYLOAD);
2192     memcpy(seg->buf, buf, size);
2193     seg->size = size;
2194     seg->packets = 1;
2195     seg->dup_ack = 0;
2196     seg->is_coalesced = 0;
2197     seg->nc = nc;
2198 
2199     QTAILQ_INSERT_TAIL(&chain->buffers, seg, next);
2200     chain->stat.cache++;
2201 
2202     switch (chain->proto) {
2203     case ETH_P_IP:
2204         virtio_net_rsc_extract_unit4(chain, seg->buf, &seg->unit);
2205         break;
2206     case ETH_P_IPV6:
2207         virtio_net_rsc_extract_unit6(chain, seg->buf, &seg->unit);
2208         break;
2209     default:
2210         g_assert_not_reached();
2211     }
2212 }
2213 
2214 static int32_t virtio_net_rsc_handle_ack(VirtioNetRscChain *chain,
2215                                          VirtioNetRscSeg *seg,
2216                                          const uint8_t *buf,
2217                                          struct tcp_header *n_tcp,
2218                                          struct tcp_header *o_tcp)
2219 {
2220     uint32_t nack, oack;
2221     uint16_t nwin, owin;
2222 
2223     nack = htonl(n_tcp->th_ack);
2224     nwin = htons(n_tcp->th_win);
2225     oack = htonl(o_tcp->th_ack);
2226     owin = htons(o_tcp->th_win);
2227 
2228     if ((nack - oack) >= VIRTIO_NET_MAX_TCP_PAYLOAD) {
2229         chain->stat.ack_out_of_win++;
2230         return RSC_FINAL;
2231     } else if (nack == oack) {
2232         /* duplicated ack or window probe */
2233         if (nwin == owin) {
2234             /* duplicated ack, add dup ack count due to whql test up to 1 */
2235             chain->stat.dup_ack++;
2236             return RSC_FINAL;
2237         } else {
2238             /* Coalesce window update */
2239             o_tcp->th_win = n_tcp->th_win;
2240             chain->stat.win_update++;
2241             return RSC_COALESCE;
2242         }
2243     } else {
2244         /* pure ack, go to 'C', finalize*/
2245         chain->stat.pure_ack++;
2246         return RSC_FINAL;
2247     }
2248 }
2249 
2250 static int32_t virtio_net_rsc_coalesce_data(VirtioNetRscChain *chain,
2251                                             VirtioNetRscSeg *seg,
2252                                             const uint8_t *buf,
2253                                             VirtioNetRscUnit *n_unit)
2254 {
2255     void *data;
2256     uint16_t o_ip_len;
2257     uint32_t nseq, oseq;
2258     VirtioNetRscUnit *o_unit;
2259 
2260     o_unit = &seg->unit;
2261     o_ip_len = read_unit_ip_len(o_unit);
2262     nseq = htonl(n_unit->tcp->th_seq);
2263     oseq = htonl(o_unit->tcp->th_seq);
2264 
2265     /* out of order or retransmitted. */
2266     if ((nseq - oseq) > VIRTIO_NET_MAX_TCP_PAYLOAD) {
2267         chain->stat.data_out_of_win++;
2268         return RSC_FINAL;
2269     }
2270 
2271     data = ((uint8_t *)n_unit->tcp) + n_unit->tcp_hdrlen;
2272     if (nseq == oseq) {
2273         if ((o_unit->payload == 0) && n_unit->payload) {
2274             /* From no payload to payload, normal case, not a dup ack or etc */
2275             chain->stat.data_after_pure_ack++;
2276             goto coalesce;
2277         } else {
2278             return virtio_net_rsc_handle_ack(chain, seg, buf,
2279                                              n_unit->tcp, o_unit->tcp);
2280         }
2281     } else if ((nseq - oseq) != o_unit->payload) {
2282         /* Not a consistent packet, out of order */
2283         chain->stat.data_out_of_order++;
2284         return RSC_FINAL;
2285     } else {
2286 coalesce:
2287         if ((o_ip_len + n_unit->payload) > chain->max_payload) {
2288             chain->stat.over_size++;
2289             return RSC_FINAL;
2290         }
2291 
2292         /* Here comes the right data, the payload length in v4/v6 is different,
2293            so use the field value to update and record the new data len */
2294         o_unit->payload += n_unit->payload; /* update new data len */
2295 
2296         /* update field in ip header */
2297         write_unit_ip_len(o_unit, o_ip_len + n_unit->payload);
2298 
2299         /* Bring 'PUSH' big, the whql test guide says 'PUSH' can be coalesced
2300            for windows guest, while this may change the behavior for linux
2301            guest (only if it uses RSC feature). */
2302         o_unit->tcp->th_offset_flags = n_unit->tcp->th_offset_flags;
2303 
2304         o_unit->tcp->th_ack = n_unit->tcp->th_ack;
2305         o_unit->tcp->th_win = n_unit->tcp->th_win;
2306 
2307         memmove(seg->buf + seg->size, data, n_unit->payload);
2308         seg->size += n_unit->payload;
2309         seg->packets++;
2310         chain->stat.coalesced++;
2311         return RSC_COALESCE;
2312     }
2313 }
2314 
2315 static int32_t virtio_net_rsc_coalesce4(VirtioNetRscChain *chain,
2316                                         VirtioNetRscSeg *seg,
2317                                         const uint8_t *buf, size_t size,
2318                                         VirtioNetRscUnit *unit)
2319 {
2320     struct ip_header *ip1, *ip2;
2321 
2322     ip1 = (struct ip_header *)(unit->ip);
2323     ip2 = (struct ip_header *)(seg->unit.ip);
2324     if ((ip1->ip_src ^ ip2->ip_src) || (ip1->ip_dst ^ ip2->ip_dst)
2325         || (unit->tcp->th_sport ^ seg->unit.tcp->th_sport)
2326         || (unit->tcp->th_dport ^ seg->unit.tcp->th_dport)) {
2327         chain->stat.no_match++;
2328         return RSC_NO_MATCH;
2329     }
2330 
2331     return virtio_net_rsc_coalesce_data(chain, seg, buf, unit);
2332 }
2333 
2334 static int32_t virtio_net_rsc_coalesce6(VirtioNetRscChain *chain,
2335                                         VirtioNetRscSeg *seg,
2336                                         const uint8_t *buf, size_t size,
2337                                         VirtioNetRscUnit *unit)
2338 {
2339     struct ip6_header *ip1, *ip2;
2340 
2341     ip1 = (struct ip6_header *)(unit->ip);
2342     ip2 = (struct ip6_header *)(seg->unit.ip);
2343     if (memcmp(&ip1->ip6_src, &ip2->ip6_src, sizeof(struct in6_address))
2344         || memcmp(&ip1->ip6_dst, &ip2->ip6_dst, sizeof(struct in6_address))
2345         || (unit->tcp->th_sport ^ seg->unit.tcp->th_sport)
2346         || (unit->tcp->th_dport ^ seg->unit.tcp->th_dport)) {
2347             chain->stat.no_match++;
2348             return RSC_NO_MATCH;
2349     }
2350 
2351     return virtio_net_rsc_coalesce_data(chain, seg, buf, unit);
2352 }
2353 
2354 /* Packets with 'SYN' should bypass, other flag should be sent after drain
2355  * to prevent out of order */
2356 static int virtio_net_rsc_tcp_ctrl_check(VirtioNetRscChain *chain,
2357                                          struct tcp_header *tcp)
2358 {
2359     uint16_t tcp_hdr;
2360     uint16_t tcp_flag;
2361 
2362     tcp_flag = htons(tcp->th_offset_flags);
2363     tcp_hdr = (tcp_flag & VIRTIO_NET_TCP_HDR_LENGTH) >> 10;
2364     tcp_flag &= VIRTIO_NET_TCP_FLAG;
2365     if (tcp_flag & TH_SYN) {
2366         chain->stat.tcp_syn++;
2367         return RSC_BYPASS;
2368     }
2369 
2370     if (tcp_flag & (TH_FIN | TH_URG | TH_RST | TH_ECE | TH_CWR)) {
2371         chain->stat.tcp_ctrl_drain++;
2372         return RSC_FINAL;
2373     }
2374 
2375     if (tcp_hdr > sizeof(struct tcp_header)) {
2376         chain->stat.tcp_all_opt++;
2377         return RSC_FINAL;
2378     }
2379 
2380     return RSC_CANDIDATE;
2381 }
2382 
2383 static size_t virtio_net_rsc_do_coalesce(VirtioNetRscChain *chain,
2384                                          NetClientState *nc,
2385                                          const uint8_t *buf, size_t size,
2386                                          VirtioNetRscUnit *unit)
2387 {
2388     int ret;
2389     VirtioNetRscSeg *seg, *nseg;
2390 
2391     if (QTAILQ_EMPTY(&chain->buffers)) {
2392         chain->stat.empty_cache++;
2393         virtio_net_rsc_cache_buf(chain, nc, buf, size);
2394         timer_mod(chain->drain_timer,
2395               qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + chain->n->rsc_timeout);
2396         return size;
2397     }
2398 
2399     QTAILQ_FOREACH_SAFE(seg, &chain->buffers, next, nseg) {
2400         if (chain->proto == ETH_P_IP) {
2401             ret = virtio_net_rsc_coalesce4(chain, seg, buf, size, unit);
2402         } else {
2403             ret = virtio_net_rsc_coalesce6(chain, seg, buf, size, unit);
2404         }
2405 
2406         if (ret == RSC_FINAL) {
2407             if (virtio_net_rsc_drain_seg(chain, seg) == 0) {
2408                 /* Send failed */
2409                 chain->stat.final_failed++;
2410                 return 0;
2411             }
2412 
2413             /* Send current packet */
2414             return virtio_net_do_receive(nc, buf, size);
2415         } else if (ret == RSC_NO_MATCH) {
2416             continue;
2417         } else {
2418             /* Coalesced, mark coalesced flag to tell calc cksum for ipv4 */
2419             seg->is_coalesced = 1;
2420             return size;
2421         }
2422     }
2423 
2424     chain->stat.no_match_cache++;
2425     virtio_net_rsc_cache_buf(chain, nc, buf, size);
2426     return size;
2427 }
2428 
2429 /* Drain a connection data, this is to avoid out of order segments */
2430 static size_t virtio_net_rsc_drain_flow(VirtioNetRscChain *chain,
2431                                         NetClientState *nc,
2432                                         const uint8_t *buf, size_t size,
2433                                         uint16_t ip_start, uint16_t ip_size,
2434                                         uint16_t tcp_port)
2435 {
2436     VirtioNetRscSeg *seg, *nseg;
2437     uint32_t ppair1, ppair2;
2438 
2439     ppair1 = *(uint32_t *)(buf + tcp_port);
2440     QTAILQ_FOREACH_SAFE(seg, &chain->buffers, next, nseg) {
2441         ppair2 = *(uint32_t *)(seg->buf + tcp_port);
2442         if (memcmp(buf + ip_start, seg->buf + ip_start, ip_size)
2443             || (ppair1 != ppair2)) {
2444             continue;
2445         }
2446         if (virtio_net_rsc_drain_seg(chain, seg) == 0) {
2447             chain->stat.drain_failed++;
2448         }
2449 
2450         break;
2451     }
2452 
2453     return virtio_net_do_receive(nc, buf, size);
2454 }
2455 
2456 static int32_t virtio_net_rsc_sanity_check4(VirtioNetRscChain *chain,
2457                                             struct ip_header *ip,
2458                                             const uint8_t *buf, size_t size)
2459 {
2460     uint16_t ip_len;
2461 
2462     /* Not an ipv4 packet */
2463     if (((ip->ip_ver_len & 0xF0) >> 4) != IP_HEADER_VERSION_4) {
2464         chain->stat.ip_option++;
2465         return RSC_BYPASS;
2466     }
2467 
2468     /* Don't handle packets with ip option */
2469     if ((ip->ip_ver_len & 0xF) != VIRTIO_NET_IP4_HEADER_LENGTH) {
2470         chain->stat.ip_option++;
2471         return RSC_BYPASS;
2472     }
2473 
2474     if (ip->ip_p != IPPROTO_TCP) {
2475         chain->stat.bypass_not_tcp++;
2476         return RSC_BYPASS;
2477     }
2478 
2479     /* Don't handle packets with ip fragment */
2480     if (!(htons(ip->ip_off) & IP_DF)) {
2481         chain->stat.ip_frag++;
2482         return RSC_BYPASS;
2483     }
2484 
2485     /* Don't handle packets with ecn flag */
2486     if (IPTOS_ECN(ip->ip_tos)) {
2487         chain->stat.ip_ecn++;
2488         return RSC_BYPASS;
2489     }
2490 
2491     ip_len = htons(ip->ip_len);
2492     if (ip_len < (sizeof(struct ip_header) + sizeof(struct tcp_header))
2493         || ip_len > (size - chain->n->guest_hdr_len -
2494                      sizeof(struct eth_header))) {
2495         chain->stat.ip_hacked++;
2496         return RSC_BYPASS;
2497     }
2498 
2499     return RSC_CANDIDATE;
2500 }
2501 
2502 static size_t virtio_net_rsc_receive4(VirtioNetRscChain *chain,
2503                                       NetClientState *nc,
2504                                       const uint8_t *buf, size_t size)
2505 {
2506     int32_t ret;
2507     uint16_t hdr_len;
2508     VirtioNetRscUnit unit;
2509 
2510     hdr_len = ((VirtIONet *)(chain->n))->guest_hdr_len;
2511 
2512     if (size < (hdr_len + sizeof(struct eth_header) + sizeof(struct ip_header)
2513         + sizeof(struct tcp_header))) {
2514         chain->stat.bypass_not_tcp++;
2515         return virtio_net_do_receive(nc, buf, size);
2516     }
2517 
2518     virtio_net_rsc_extract_unit4(chain, buf, &unit);
2519     if (virtio_net_rsc_sanity_check4(chain, unit.ip, buf, size)
2520         != RSC_CANDIDATE) {
2521         return virtio_net_do_receive(nc, buf, size);
2522     }
2523 
2524     ret = virtio_net_rsc_tcp_ctrl_check(chain, unit.tcp);
2525     if (ret == RSC_BYPASS) {
2526         return virtio_net_do_receive(nc, buf, size);
2527     } else if (ret == RSC_FINAL) {
2528         return virtio_net_rsc_drain_flow(chain, nc, buf, size,
2529                 ((hdr_len + sizeof(struct eth_header)) + 12),
2530                 VIRTIO_NET_IP4_ADDR_SIZE,
2531                 hdr_len + sizeof(struct eth_header) + sizeof(struct ip_header));
2532     }
2533 
2534     return virtio_net_rsc_do_coalesce(chain, nc, buf, size, &unit);
2535 }
2536 
2537 static int32_t virtio_net_rsc_sanity_check6(VirtioNetRscChain *chain,
2538                                             struct ip6_header *ip6,
2539                                             const uint8_t *buf, size_t size)
2540 {
2541     uint16_t ip_len;
2542 
2543     if (((ip6->ip6_ctlun.ip6_un1.ip6_un1_flow & 0xF0) >> 4)
2544         != IP_HEADER_VERSION_6) {
2545         return RSC_BYPASS;
2546     }
2547 
2548     /* Both option and protocol is checked in this */
2549     if (ip6->ip6_ctlun.ip6_un1.ip6_un1_nxt != IPPROTO_TCP) {
2550         chain->stat.bypass_not_tcp++;
2551         return RSC_BYPASS;
2552     }
2553 
2554     ip_len = htons(ip6->ip6_ctlun.ip6_un1.ip6_un1_plen);
2555     if (ip_len < sizeof(struct tcp_header) ||
2556         ip_len > (size - chain->n->guest_hdr_len - sizeof(struct eth_header)
2557                   - sizeof(struct ip6_header))) {
2558         chain->stat.ip_hacked++;
2559         return RSC_BYPASS;
2560     }
2561 
2562     /* Don't handle packets with ecn flag */
2563     if (IP6_ECN(ip6->ip6_ctlun.ip6_un3.ip6_un3_ecn)) {
2564         chain->stat.ip_ecn++;
2565         return RSC_BYPASS;
2566     }
2567 
2568     return RSC_CANDIDATE;
2569 }
2570 
2571 static size_t virtio_net_rsc_receive6(void *opq, NetClientState *nc,
2572                                       const uint8_t *buf, size_t size)
2573 {
2574     int32_t ret;
2575     uint16_t hdr_len;
2576     VirtioNetRscChain *chain;
2577     VirtioNetRscUnit unit;
2578 
2579     chain = opq;
2580     hdr_len = ((VirtIONet *)(chain->n))->guest_hdr_len;
2581 
2582     if (size < (hdr_len + sizeof(struct eth_header) + sizeof(struct ip6_header)
2583         + sizeof(tcp_header))) {
2584         return virtio_net_do_receive(nc, buf, size);
2585     }
2586 
2587     virtio_net_rsc_extract_unit6(chain, buf, &unit);
2588     if (RSC_CANDIDATE != virtio_net_rsc_sanity_check6(chain,
2589                                                  unit.ip, buf, size)) {
2590         return virtio_net_do_receive(nc, buf, size);
2591     }
2592 
2593     ret = virtio_net_rsc_tcp_ctrl_check(chain, unit.tcp);
2594     if (ret == RSC_BYPASS) {
2595         return virtio_net_do_receive(nc, buf, size);
2596     } else if (ret == RSC_FINAL) {
2597         return virtio_net_rsc_drain_flow(chain, nc, buf, size,
2598                 ((hdr_len + sizeof(struct eth_header)) + 8),
2599                 VIRTIO_NET_IP6_ADDR_SIZE,
2600                 hdr_len + sizeof(struct eth_header)
2601                 + sizeof(struct ip6_header));
2602     }
2603 
2604     return virtio_net_rsc_do_coalesce(chain, nc, buf, size, &unit);
2605 }
2606 
2607 static VirtioNetRscChain *virtio_net_rsc_lookup_chain(VirtIONet *n,
2608                                                       NetClientState *nc,
2609                                                       uint16_t proto)
2610 {
2611     VirtioNetRscChain *chain;
2612 
2613     if ((proto != (uint16_t)ETH_P_IP) && (proto != (uint16_t)ETH_P_IPV6)) {
2614         return NULL;
2615     }
2616 
2617     QTAILQ_FOREACH(chain, &n->rsc_chains, next) {
2618         if (chain->proto == proto) {
2619             return chain;
2620         }
2621     }
2622 
2623     chain = g_malloc(sizeof(*chain));
2624     chain->n = n;
2625     chain->proto = proto;
2626     if (proto == (uint16_t)ETH_P_IP) {
2627         chain->max_payload = VIRTIO_NET_MAX_IP4_PAYLOAD;
2628         chain->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
2629     } else {
2630         chain->max_payload = VIRTIO_NET_MAX_IP6_PAYLOAD;
2631         chain->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
2632     }
2633     chain->drain_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
2634                                       virtio_net_rsc_purge, chain);
2635     memset(&chain->stat, 0, sizeof(chain->stat));
2636 
2637     QTAILQ_INIT(&chain->buffers);
2638     QTAILQ_INSERT_TAIL(&n->rsc_chains, chain, next);
2639 
2640     return chain;
2641 }
2642 
2643 static ssize_t virtio_net_rsc_receive(NetClientState *nc,
2644                                       const uint8_t *buf,
2645                                       size_t size)
2646 {
2647     uint16_t proto;
2648     VirtioNetRscChain *chain;
2649     struct eth_header *eth;
2650     VirtIONet *n;
2651 
2652     n = qemu_get_nic_opaque(nc);
2653     if (size < (n->host_hdr_len + sizeof(struct eth_header))) {
2654         return virtio_net_do_receive(nc, buf, size);
2655     }
2656 
2657     eth = (struct eth_header *)(buf + n->guest_hdr_len);
2658     proto = htons(eth->h_proto);
2659 
2660     chain = virtio_net_rsc_lookup_chain(n, nc, proto);
2661     if (chain) {
2662         chain->stat.received++;
2663         if (proto == (uint16_t)ETH_P_IP && n->rsc4_enabled) {
2664             return virtio_net_rsc_receive4(chain, nc, buf, size);
2665         } else if (proto == (uint16_t)ETH_P_IPV6 && n->rsc6_enabled) {
2666             return virtio_net_rsc_receive6(chain, nc, buf, size);
2667         }
2668     }
2669     return virtio_net_do_receive(nc, buf, size);
2670 }
2671 
2672 static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf,
2673                                   size_t size)
2674 {
2675     VirtIONet *n = qemu_get_nic_opaque(nc);
2676     if ((n->rsc4_enabled || n->rsc6_enabled)) {
2677         return virtio_net_rsc_receive(nc, buf, size);
2678     } else {
2679         return virtio_net_do_receive(nc, buf, size);
2680     }
2681 }
2682 
2683 static int32_t virtio_net_flush_tx(VirtIONetQueue *q);
2684 
2685 static void virtio_net_tx_complete(NetClientState *nc, ssize_t len)
2686 {
2687     VirtIONet *n = qemu_get_nic_opaque(nc);
2688     VirtIONetQueue *q = virtio_net_get_subqueue(nc);
2689     VirtIODevice *vdev = VIRTIO_DEVICE(n);
2690     int ret;
2691 
2692     virtqueue_push(q->tx_vq, q->async_tx.elem, 0);
2693     virtio_notify(vdev, q->tx_vq);
2694 
2695     g_free(q->async_tx.elem);
2696     q->async_tx.elem = NULL;
2697 
2698     virtio_queue_set_notification(q->tx_vq, 1);
2699     ret = virtio_net_flush_tx(q);
2700     if (ret >= n->tx_burst) {
2701         /*
2702          * the flush has been stopped by tx_burst
2703          * we will not receive notification for the
2704          * remainining part, so re-schedule
2705          */
2706         virtio_queue_set_notification(q->tx_vq, 0);
2707         if (q->tx_bh) {
2708             replay_bh_schedule_event(q->tx_bh);
2709         } else {
2710             timer_mod(q->tx_timer,
2711                       qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + n->tx_timeout);
2712         }
2713         q->tx_waiting = 1;
2714     }
2715 }
2716 
2717 /* TX */
2718 static int32_t virtio_net_flush_tx(VirtIONetQueue *q)
2719 {
2720     VirtIONet *n = q->n;
2721     VirtIODevice *vdev = VIRTIO_DEVICE(n);
2722     VirtQueueElement *elem;
2723     int32_t num_packets = 0;
2724     int queue_index = vq2q(virtio_get_queue_index(q->tx_vq));
2725     if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
2726         return num_packets;
2727     }
2728 
2729     if (q->async_tx.elem) {
2730         virtio_queue_set_notification(q->tx_vq, 0);
2731         return num_packets;
2732     }
2733 
2734     for (;;) {
2735         ssize_t ret;
2736         unsigned int out_num;
2737         struct iovec sg[VIRTQUEUE_MAX_SIZE], sg2[VIRTQUEUE_MAX_SIZE + 1], *out_sg;
2738         struct virtio_net_hdr vhdr;
2739 
2740         elem = virtqueue_pop(q->tx_vq, sizeof(VirtQueueElement));
2741         if (!elem) {
2742             break;
2743         }
2744 
2745         out_num = elem->out_num;
2746         out_sg = elem->out_sg;
2747         if (out_num < 1) {
2748             virtio_error(vdev, "virtio-net header not in first element");
2749             goto detach;
2750         }
2751 
2752         if (n->needs_vnet_hdr_swap) {
2753             if (iov_to_buf(out_sg, out_num, 0, &vhdr, sizeof(vhdr)) <
2754                 sizeof(vhdr)) {
2755                 virtio_error(vdev, "virtio-net header incorrect");
2756                 goto detach;
2757             }
2758             virtio_net_hdr_swap(vdev, &vhdr);
2759             sg2[0].iov_base = &vhdr;
2760             sg2[0].iov_len = sizeof(vhdr);
2761             out_num = iov_copy(&sg2[1], ARRAY_SIZE(sg2) - 1, out_sg, out_num,
2762                                sizeof(vhdr), -1);
2763             if (out_num == VIRTQUEUE_MAX_SIZE) {
2764                 goto drop;
2765             }
2766             out_num += 1;
2767             out_sg = sg2;
2768         }
2769         /*
2770          * If host wants to see the guest header as is, we can
2771          * pass it on unchanged. Otherwise, copy just the parts
2772          * that host is interested in.
2773          */
2774         assert(n->host_hdr_len <= n->guest_hdr_len);
2775         if (n->host_hdr_len != n->guest_hdr_len) {
2776             if (iov_size(out_sg, out_num) < n->guest_hdr_len) {
2777                 virtio_error(vdev, "virtio-net header is invalid");
2778                 goto detach;
2779             }
2780             unsigned sg_num = iov_copy(sg, ARRAY_SIZE(sg),
2781                                        out_sg, out_num,
2782                                        0, n->host_hdr_len);
2783             sg_num += iov_copy(sg + sg_num, ARRAY_SIZE(sg) - sg_num,
2784                              out_sg, out_num,
2785                              n->guest_hdr_len, -1);
2786             out_num = sg_num;
2787             out_sg = sg;
2788 
2789             if (out_num < 1) {
2790                 virtio_error(vdev, "virtio-net nothing to send");
2791                 goto detach;
2792             }
2793         }
2794 
2795         ret = qemu_sendv_packet_async(qemu_get_subqueue(n->nic, queue_index),
2796                                       out_sg, out_num, virtio_net_tx_complete);
2797         if (ret == 0) {
2798             virtio_queue_set_notification(q->tx_vq, 0);
2799             q->async_tx.elem = elem;
2800             return -EBUSY;
2801         }
2802 
2803 drop:
2804         virtqueue_push(q->tx_vq, elem, 0);
2805         virtio_notify(vdev, q->tx_vq);
2806         g_free(elem);
2807 
2808         if (++num_packets >= n->tx_burst) {
2809             break;
2810         }
2811     }
2812     return num_packets;
2813 
2814 detach:
2815     virtqueue_detach_element(q->tx_vq, elem, 0);
2816     g_free(elem);
2817     return -EINVAL;
2818 }
2819 
2820 static void virtio_net_tx_timer(void *opaque);
2821 
2822 static void virtio_net_handle_tx_timer(VirtIODevice *vdev, VirtQueue *vq)
2823 {
2824     VirtIONet *n = VIRTIO_NET(vdev);
2825     VirtIONetQueue *q = &n->vqs[vq2q(virtio_get_queue_index(vq))];
2826 
2827     if (unlikely((n->status & VIRTIO_NET_S_LINK_UP) == 0)) {
2828         virtio_net_drop_tx_queue_data(vdev, vq);
2829         return;
2830     }
2831 
2832     /* This happens when device was stopped but VCPU wasn't. */
2833     if (!vdev->vm_running) {
2834         q->tx_waiting = 1;
2835         return;
2836     }
2837 
2838     if (q->tx_waiting) {
2839         /* We already have queued packets, immediately flush */
2840         timer_del(q->tx_timer);
2841         virtio_net_tx_timer(q);
2842     } else {
2843         /* re-arm timer to flush it (and more) on next tick */
2844         timer_mod(q->tx_timer,
2845                   qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + n->tx_timeout);
2846         q->tx_waiting = 1;
2847         virtio_queue_set_notification(vq, 0);
2848     }
2849 }
2850 
2851 static void virtio_net_handle_tx_bh(VirtIODevice *vdev, VirtQueue *vq)
2852 {
2853     VirtIONet *n = VIRTIO_NET(vdev);
2854     VirtIONetQueue *q = &n->vqs[vq2q(virtio_get_queue_index(vq))];
2855 
2856     if (unlikely(n->vhost_started)) {
2857         return;
2858     }
2859 
2860     if (unlikely((n->status & VIRTIO_NET_S_LINK_UP) == 0)) {
2861         virtio_net_drop_tx_queue_data(vdev, vq);
2862         return;
2863     }
2864 
2865     if (unlikely(q->tx_waiting)) {
2866         return;
2867     }
2868     q->tx_waiting = 1;
2869     /* This happens when device was stopped but VCPU wasn't. */
2870     if (!vdev->vm_running) {
2871         return;
2872     }
2873     virtio_queue_set_notification(vq, 0);
2874     replay_bh_schedule_event(q->tx_bh);
2875 }
2876 
2877 static void virtio_net_tx_timer(void *opaque)
2878 {
2879     VirtIONetQueue *q = opaque;
2880     VirtIONet *n = q->n;
2881     VirtIODevice *vdev = VIRTIO_DEVICE(n);
2882     int ret;
2883 
2884     /* This happens when device was stopped but BH wasn't. */
2885     if (!vdev->vm_running) {
2886         /* Make sure tx waiting is set, so we'll run when restarted. */
2887         assert(q->tx_waiting);
2888         return;
2889     }
2890 
2891     q->tx_waiting = 0;
2892 
2893     /* Just in case the driver is not ready on more */
2894     if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
2895         return;
2896     }
2897 
2898     ret = virtio_net_flush_tx(q);
2899     if (ret == -EBUSY || ret == -EINVAL) {
2900         return;
2901     }
2902     /*
2903      * If we flush a full burst of packets, assume there are
2904      * more coming and immediately rearm
2905      */
2906     if (ret >= n->tx_burst) {
2907         q->tx_waiting = 1;
2908         timer_mod(q->tx_timer,
2909                   qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + n->tx_timeout);
2910         return;
2911     }
2912     /*
2913      * If less than a full burst, re-enable notification and flush
2914      * anything that may have come in while we weren't looking.  If
2915      * we find something, assume the guest is still active and rearm
2916      */
2917     virtio_queue_set_notification(q->tx_vq, 1);
2918     ret = virtio_net_flush_tx(q);
2919     if (ret > 0) {
2920         virtio_queue_set_notification(q->tx_vq, 0);
2921         q->tx_waiting = 1;
2922         timer_mod(q->tx_timer,
2923                   qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + n->tx_timeout);
2924     }
2925 }
2926 
2927 static void virtio_net_tx_bh(void *opaque)
2928 {
2929     VirtIONetQueue *q = opaque;
2930     VirtIONet *n = q->n;
2931     VirtIODevice *vdev = VIRTIO_DEVICE(n);
2932     int32_t ret;
2933 
2934     /* This happens when device was stopped but BH wasn't. */
2935     if (!vdev->vm_running) {
2936         /* Make sure tx waiting is set, so we'll run when restarted. */
2937         assert(q->tx_waiting);
2938         return;
2939     }
2940 
2941     q->tx_waiting = 0;
2942 
2943     /* Just in case the driver is not ready on more */
2944     if (unlikely(!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK))) {
2945         return;
2946     }
2947 
2948     ret = virtio_net_flush_tx(q);
2949     if (ret == -EBUSY || ret == -EINVAL) {
2950         return; /* Notification re-enable handled by tx_complete or device
2951                  * broken */
2952     }
2953 
2954     /* If we flush a full burst of packets, assume there are
2955      * more coming and immediately reschedule */
2956     if (ret >= n->tx_burst) {
2957         replay_bh_schedule_event(q->tx_bh);
2958         q->tx_waiting = 1;
2959         return;
2960     }
2961 
2962     /* If less than a full burst, re-enable notification and flush
2963      * anything that may have come in while we weren't looking.  If
2964      * we find something, assume the guest is still active and reschedule */
2965     virtio_queue_set_notification(q->tx_vq, 1);
2966     ret = virtio_net_flush_tx(q);
2967     if (ret == -EINVAL) {
2968         return;
2969     } else if (ret > 0) {
2970         virtio_queue_set_notification(q->tx_vq, 0);
2971         replay_bh_schedule_event(q->tx_bh);
2972         q->tx_waiting = 1;
2973     }
2974 }
2975 
2976 static void virtio_net_add_queue(VirtIONet *n, int index)
2977 {
2978     VirtIODevice *vdev = VIRTIO_DEVICE(n);
2979 
2980     n->vqs[index].rx_vq = virtio_add_queue(vdev, n->net_conf.rx_queue_size,
2981                                            virtio_net_handle_rx);
2982 
2983     if (n->net_conf.tx && !strcmp(n->net_conf.tx, "timer")) {
2984         n->vqs[index].tx_vq =
2985             virtio_add_queue(vdev, n->net_conf.tx_queue_size,
2986                              virtio_net_handle_tx_timer);
2987         n->vqs[index].tx_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
2988                                               virtio_net_tx_timer,
2989                                               &n->vqs[index]);
2990     } else {
2991         n->vqs[index].tx_vq =
2992             virtio_add_queue(vdev, n->net_conf.tx_queue_size,
2993                              virtio_net_handle_tx_bh);
2994         n->vqs[index].tx_bh = qemu_bh_new_guarded(virtio_net_tx_bh, &n->vqs[index],
2995                                                   &DEVICE(vdev)->mem_reentrancy_guard);
2996     }
2997 
2998     n->vqs[index].tx_waiting = 0;
2999     n->vqs[index].n = n;
3000 }
3001 
3002 static void virtio_net_del_queue(VirtIONet *n, int index)
3003 {
3004     VirtIODevice *vdev = VIRTIO_DEVICE(n);
3005     VirtIONetQueue *q = &n->vqs[index];
3006     NetClientState *nc = qemu_get_subqueue(n->nic, index);
3007 
3008     qemu_purge_queued_packets(nc);
3009 
3010     virtio_del_queue(vdev, index * 2);
3011     if (q->tx_timer) {
3012         timer_free(q->tx_timer);
3013         q->tx_timer = NULL;
3014     } else {
3015         qemu_bh_delete(q->tx_bh);
3016         q->tx_bh = NULL;
3017     }
3018     q->tx_waiting = 0;
3019     virtio_del_queue(vdev, index * 2 + 1);
3020 }
3021 
3022 static void virtio_net_change_num_queue_pairs(VirtIONet *n, int new_max_queue_pairs)
3023 {
3024     VirtIODevice *vdev = VIRTIO_DEVICE(n);
3025     int old_num_queues = virtio_get_num_queues(vdev);
3026     int new_num_queues = new_max_queue_pairs * 2 + 1;
3027     int i;
3028 
3029     assert(old_num_queues >= 3);
3030     assert(old_num_queues % 2 == 1);
3031 
3032     if (old_num_queues == new_num_queues) {
3033         return;
3034     }
3035 
3036     /*
3037      * We always need to remove and add ctrl vq if
3038      * old_num_queues != new_num_queues. Remove ctrl_vq first,
3039      * and then we only enter one of the following two loops.
3040      */
3041     virtio_del_queue(vdev, old_num_queues - 1);
3042 
3043     for (i = new_num_queues - 1; i < old_num_queues - 1; i += 2) {
3044         /* new_num_queues < old_num_queues */
3045         virtio_net_del_queue(n, i / 2);
3046     }
3047 
3048     for (i = old_num_queues - 1; i < new_num_queues - 1; i += 2) {
3049         /* new_num_queues > old_num_queues */
3050         virtio_net_add_queue(n, i / 2);
3051     }
3052 
3053     /* add ctrl_vq last */
3054     n->ctrl_vq = virtio_add_queue(vdev, 64, virtio_net_handle_ctrl);
3055 }
3056 
3057 static void virtio_net_set_multiqueue(VirtIONet *n, int multiqueue)
3058 {
3059     int max = multiqueue ? n->max_queue_pairs : 1;
3060 
3061     n->multiqueue = multiqueue;
3062     virtio_net_change_num_queue_pairs(n, max);
3063 
3064     virtio_net_set_queue_pairs(n);
3065 }
3066 
3067 static int virtio_net_pre_load_queues(VirtIODevice *vdev)
3068 {
3069     virtio_net_set_multiqueue(VIRTIO_NET(vdev),
3070                               virtio_has_feature(vdev->guest_features, VIRTIO_NET_F_RSS) ||
3071                               virtio_has_feature(vdev->guest_features, VIRTIO_NET_F_MQ));
3072 
3073     return 0;
3074 }
3075 
3076 static int virtio_net_post_load_device(void *opaque, int version_id)
3077 {
3078     VirtIONet *n = opaque;
3079     VirtIODevice *vdev = VIRTIO_DEVICE(n);
3080     int i, link_down;
3081 
3082     trace_virtio_net_post_load_device();
3083     virtio_net_set_mrg_rx_bufs(n, n->mergeable_rx_bufs,
3084                                virtio_vdev_has_feature(vdev,
3085                                                        VIRTIO_F_VERSION_1),
3086                                virtio_vdev_has_feature(vdev,
3087                                                        VIRTIO_NET_F_HASH_REPORT));
3088 
3089     /* MAC_TABLE_ENTRIES may be different from the saved image */
3090     if (n->mac_table.in_use > MAC_TABLE_ENTRIES) {
3091         n->mac_table.in_use = 0;
3092     }
3093 
3094     if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)) {
3095         n->curr_guest_offloads = virtio_net_supported_guest_offloads(n);
3096     }
3097 
3098     /*
3099      * curr_guest_offloads will be later overwritten by the
3100      * virtio_set_features_nocheck call done from the virtio_load.
3101      * Here we make sure it is preserved and restored accordingly
3102      * in the virtio_net_post_load_virtio callback.
3103      */
3104     n->saved_guest_offloads = n->curr_guest_offloads;
3105 
3106     virtio_net_set_queue_pairs(n);
3107 
3108     /* Find the first multicast entry in the saved MAC filter */
3109     for (i = 0; i < n->mac_table.in_use; i++) {
3110         if (n->mac_table.macs[i * ETH_ALEN] & 1) {
3111             break;
3112         }
3113     }
3114     n->mac_table.first_multi = i;
3115 
3116     /* nc.link_down can't be migrated, so infer link_down according
3117      * to link status bit in n->status */
3118     link_down = (n->status & VIRTIO_NET_S_LINK_UP) == 0;
3119     for (i = 0; i < n->max_queue_pairs; i++) {
3120         qemu_get_subqueue(n->nic, i)->link_down = link_down;
3121     }
3122 
3123     if (virtio_vdev_has_feature(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE) &&
3124         virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) {
3125         qemu_announce_timer_reset(&n->announce_timer, migrate_announce_params(),
3126                                   QEMU_CLOCK_VIRTUAL,
3127                                   virtio_net_announce_timer, n);
3128         if (n->announce_timer.round) {
3129             timer_mod(n->announce_timer.tm,
3130                       qemu_clock_get_ms(n->announce_timer.type));
3131         } else {
3132             qemu_announce_timer_del(&n->announce_timer, false);
3133         }
3134     }
3135 
3136     virtio_net_commit_rss_config(n);
3137     return 0;
3138 }
3139 
3140 static int virtio_net_post_load_virtio(VirtIODevice *vdev)
3141 {
3142     VirtIONet *n = VIRTIO_NET(vdev);
3143     /*
3144      * The actual needed state is now in saved_guest_offloads,
3145      * see virtio_net_post_load_device for detail.
3146      * Restore it back and apply the desired offloads.
3147      */
3148     n->curr_guest_offloads = n->saved_guest_offloads;
3149     if (peer_has_vnet_hdr(n)) {
3150         virtio_net_apply_guest_offloads(n);
3151     }
3152 
3153     return 0;
3154 }
3155 
3156 /* tx_waiting field of a VirtIONetQueue */
3157 static const VMStateDescription vmstate_virtio_net_queue_tx_waiting = {
3158     .name = "virtio-net-queue-tx_waiting",
3159     .fields = (const VMStateField[]) {
3160         VMSTATE_UINT32(tx_waiting, VirtIONetQueue),
3161         VMSTATE_END_OF_LIST()
3162    },
3163 };
3164 
3165 static bool max_queue_pairs_gt_1(void *opaque, int version_id)
3166 {
3167     return VIRTIO_NET(opaque)->max_queue_pairs > 1;
3168 }
3169 
3170 static bool has_ctrl_guest_offloads(void *opaque, int version_id)
3171 {
3172     return virtio_vdev_has_feature(VIRTIO_DEVICE(opaque),
3173                                    VIRTIO_NET_F_CTRL_GUEST_OFFLOADS);
3174 }
3175 
3176 static bool mac_table_fits(void *opaque, int version_id)
3177 {
3178     return VIRTIO_NET(opaque)->mac_table.in_use <= MAC_TABLE_ENTRIES;
3179 }
3180 
3181 static bool mac_table_doesnt_fit(void *opaque, int version_id)
3182 {
3183     return !mac_table_fits(opaque, version_id);
3184 }
3185 
3186 /* This temporary type is shared by all the WITH_TMP methods
3187  * although only some fields are used by each.
3188  */
3189 struct VirtIONetMigTmp {
3190     VirtIONet      *parent;
3191     VirtIONetQueue *vqs_1;
3192     uint16_t        curr_queue_pairs_1;
3193     uint8_t         has_ufo;
3194     uint32_t        has_vnet_hdr;
3195 };
3196 
3197 /* The 2nd and subsequent tx_waiting flags are loaded later than
3198  * the 1st entry in the queue_pairs and only if there's more than one
3199  * entry.  We use the tmp mechanism to calculate a temporary
3200  * pointer and count and also validate the count.
3201  */
3202 
3203 static int virtio_net_tx_waiting_pre_save(void *opaque)
3204 {
3205     struct VirtIONetMigTmp *tmp = opaque;
3206 
3207     tmp->vqs_1 = tmp->parent->vqs + 1;
3208     tmp->curr_queue_pairs_1 = tmp->parent->curr_queue_pairs - 1;
3209     if (tmp->parent->curr_queue_pairs == 0) {
3210         tmp->curr_queue_pairs_1 = 0;
3211     }
3212 
3213     return 0;
3214 }
3215 
3216 static int virtio_net_tx_waiting_pre_load(void *opaque)
3217 {
3218     struct VirtIONetMigTmp *tmp = opaque;
3219 
3220     /* Reuse the pointer setup from save */
3221     virtio_net_tx_waiting_pre_save(opaque);
3222 
3223     if (tmp->parent->curr_queue_pairs > tmp->parent->max_queue_pairs) {
3224         error_report("virtio-net: curr_queue_pairs %x > max_queue_pairs %x",
3225             tmp->parent->curr_queue_pairs, tmp->parent->max_queue_pairs);
3226 
3227         return -EINVAL;
3228     }
3229 
3230     return 0; /* all good */
3231 }
3232 
3233 static const VMStateDescription vmstate_virtio_net_tx_waiting = {
3234     .name      = "virtio-net-tx_waiting",
3235     .pre_load  = virtio_net_tx_waiting_pre_load,
3236     .pre_save  = virtio_net_tx_waiting_pre_save,
3237     .fields    = (const VMStateField[]) {
3238         VMSTATE_STRUCT_VARRAY_POINTER_UINT16(vqs_1, struct VirtIONetMigTmp,
3239                                      curr_queue_pairs_1,
3240                                      vmstate_virtio_net_queue_tx_waiting,
3241                                      struct VirtIONetQueue),
3242         VMSTATE_END_OF_LIST()
3243     },
3244 };
3245 
3246 /* the 'has_ufo' flag is just tested; if the incoming stream has the
3247  * flag set we need to check that we have it
3248  */
3249 static int virtio_net_ufo_post_load(void *opaque, int version_id)
3250 {
3251     struct VirtIONetMigTmp *tmp = opaque;
3252 
3253     if (tmp->has_ufo && !peer_has_ufo(tmp->parent)) {
3254         error_report("virtio-net: saved image requires TUN_F_UFO support");
3255         return -EINVAL;
3256     }
3257 
3258     return 0;
3259 }
3260 
3261 static int virtio_net_ufo_pre_save(void *opaque)
3262 {
3263     struct VirtIONetMigTmp *tmp = opaque;
3264 
3265     tmp->has_ufo = tmp->parent->has_ufo;
3266 
3267     return 0;
3268 }
3269 
3270 static const VMStateDescription vmstate_virtio_net_has_ufo = {
3271     .name      = "virtio-net-ufo",
3272     .post_load = virtio_net_ufo_post_load,
3273     .pre_save  = virtio_net_ufo_pre_save,
3274     .fields    = (const VMStateField[]) {
3275         VMSTATE_UINT8(has_ufo, struct VirtIONetMigTmp),
3276         VMSTATE_END_OF_LIST()
3277     },
3278 };
3279 
3280 /* the 'has_vnet_hdr' flag is just tested; if the incoming stream has the
3281  * flag set we need to check that we have it
3282  */
3283 static int virtio_net_vnet_post_load(void *opaque, int version_id)
3284 {
3285     struct VirtIONetMigTmp *tmp = opaque;
3286 
3287     if (tmp->has_vnet_hdr && !peer_has_vnet_hdr(tmp->parent)) {
3288         error_report("virtio-net: saved image requires vnet_hdr=on");
3289         return -EINVAL;
3290     }
3291 
3292     return 0;
3293 }
3294 
3295 static int virtio_net_vnet_pre_save(void *opaque)
3296 {
3297     struct VirtIONetMigTmp *tmp = opaque;
3298 
3299     tmp->has_vnet_hdr = tmp->parent->has_vnet_hdr;
3300 
3301     return 0;
3302 }
3303 
3304 static const VMStateDescription vmstate_virtio_net_has_vnet = {
3305     .name      = "virtio-net-vnet",
3306     .post_load = virtio_net_vnet_post_load,
3307     .pre_save  = virtio_net_vnet_pre_save,
3308     .fields    = (const VMStateField[]) {
3309         VMSTATE_UINT32(has_vnet_hdr, struct VirtIONetMigTmp),
3310         VMSTATE_END_OF_LIST()
3311     },
3312 };
3313 
3314 static bool virtio_net_rss_needed(void *opaque)
3315 {
3316     return VIRTIO_NET(opaque)->rss_data.enabled;
3317 }
3318 
3319 static const VMStateDescription vmstate_virtio_net_rss = {
3320     .name      = "virtio-net-device/rss",
3321     .version_id = 1,
3322     .minimum_version_id = 1,
3323     .needed = virtio_net_rss_needed,
3324     .fields = (const VMStateField[]) {
3325         VMSTATE_BOOL(rss_data.enabled, VirtIONet),
3326         VMSTATE_BOOL(rss_data.redirect, VirtIONet),
3327         VMSTATE_BOOL(rss_data.populate_hash, VirtIONet),
3328         VMSTATE_UINT32(rss_data.hash_types, VirtIONet),
3329         VMSTATE_UINT16(rss_data.indirections_len, VirtIONet),
3330         VMSTATE_UINT16(rss_data.default_queue, VirtIONet),
3331         VMSTATE_UINT8_ARRAY(rss_data.key, VirtIONet,
3332                             VIRTIO_NET_RSS_MAX_KEY_SIZE),
3333         VMSTATE_VARRAY_UINT16_ALLOC(rss_data.indirections_table, VirtIONet,
3334                                     rss_data.indirections_len, 0,
3335                                     vmstate_info_uint16, uint16_t),
3336         VMSTATE_END_OF_LIST()
3337     },
3338 };
3339 
3340 static const VMStateDescription vmstate_virtio_net_device = {
3341     .name = "virtio-net-device",
3342     .version_id = VIRTIO_NET_VM_VERSION,
3343     .minimum_version_id = VIRTIO_NET_VM_VERSION,
3344     .post_load = virtio_net_post_load_device,
3345     .fields = (const VMStateField[]) {
3346         VMSTATE_UINT8_ARRAY(mac, VirtIONet, ETH_ALEN),
3347         VMSTATE_STRUCT_POINTER(vqs, VirtIONet,
3348                                vmstate_virtio_net_queue_tx_waiting,
3349                                VirtIONetQueue),
3350         VMSTATE_UINT32(mergeable_rx_bufs, VirtIONet),
3351         VMSTATE_UINT16(status, VirtIONet),
3352         VMSTATE_UINT8(promisc, VirtIONet),
3353         VMSTATE_UINT8(allmulti, VirtIONet),
3354         VMSTATE_UINT32(mac_table.in_use, VirtIONet),
3355 
3356         /* Guarded pair: If it fits we load it, else we throw it away
3357          * - can happen if source has a larger MAC table.; post-load
3358          *  sets flags in this case.
3359          */
3360         VMSTATE_VBUFFER_MULTIPLY(mac_table.macs, VirtIONet,
3361                                 0, mac_table_fits, mac_table.in_use,
3362                                  ETH_ALEN),
3363         VMSTATE_UNUSED_VARRAY_UINT32(VirtIONet, mac_table_doesnt_fit, 0,
3364                                      mac_table.in_use, ETH_ALEN),
3365 
3366         /* Note: This is an array of uint32's that's always been saved as a
3367          * buffer; hold onto your endiannesses; it's actually used as a bitmap
3368          * but based on the uint.
3369          */
3370         VMSTATE_BUFFER_POINTER_UNSAFE(vlans, VirtIONet, 0, MAX_VLAN >> 3),
3371         VMSTATE_WITH_TMP(VirtIONet, struct VirtIONetMigTmp,
3372                          vmstate_virtio_net_has_vnet),
3373         VMSTATE_UINT8(mac_table.multi_overflow, VirtIONet),
3374         VMSTATE_UINT8(mac_table.uni_overflow, VirtIONet),
3375         VMSTATE_UINT8(alluni, VirtIONet),
3376         VMSTATE_UINT8(nomulti, VirtIONet),
3377         VMSTATE_UINT8(nouni, VirtIONet),
3378         VMSTATE_UINT8(nobcast, VirtIONet),
3379         VMSTATE_WITH_TMP(VirtIONet, struct VirtIONetMigTmp,
3380                          vmstate_virtio_net_has_ufo),
3381         VMSTATE_SINGLE_TEST(max_queue_pairs, VirtIONet, max_queue_pairs_gt_1, 0,
3382                             vmstate_info_uint16_equal, uint16_t),
3383         VMSTATE_UINT16_TEST(curr_queue_pairs, VirtIONet, max_queue_pairs_gt_1),
3384         VMSTATE_WITH_TMP(VirtIONet, struct VirtIONetMigTmp,
3385                          vmstate_virtio_net_tx_waiting),
3386         VMSTATE_UINT64_TEST(curr_guest_offloads, VirtIONet,
3387                             has_ctrl_guest_offloads),
3388         VMSTATE_END_OF_LIST()
3389     },
3390     .subsections = (const VMStateDescription * const []) {
3391         &vmstate_virtio_net_rss,
3392         NULL
3393     }
3394 };
3395 
3396 static NetClientInfo net_virtio_info = {
3397     .type = NET_CLIENT_DRIVER_NIC,
3398     .size = sizeof(NICState),
3399     .can_receive = virtio_net_can_receive,
3400     .receive = virtio_net_receive,
3401     .link_status_changed = virtio_net_set_link_status,
3402     .query_rx_filter = virtio_net_query_rxfilter,
3403     .announce = virtio_net_announce,
3404 };
3405 
3406 static bool virtio_net_guest_notifier_pending(VirtIODevice *vdev, int idx)
3407 {
3408     VirtIONet *n = VIRTIO_NET(vdev);
3409     NetClientState *nc;
3410     assert(n->vhost_started);
3411     if (!n->multiqueue && idx == 2) {
3412         /* Must guard against invalid features and bogus queue index
3413          * from being set by malicious guest, or penetrated through
3414          * buggy migration stream.
3415          */
3416         if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) {
3417             qemu_log_mask(LOG_GUEST_ERROR,
3418                           "%s: bogus vq index ignored\n", __func__);
3419             return false;
3420         }
3421         nc = qemu_get_subqueue(n->nic, n->max_queue_pairs);
3422     } else {
3423         nc = qemu_get_subqueue(n->nic, vq2q(idx));
3424     }
3425     /*
3426      * Add the check for configure interrupt, Use VIRTIO_CONFIG_IRQ_IDX -1
3427      * as the macro of configure interrupt's IDX, If this driver does not
3428      * support, the function will return false
3429      */
3430 
3431     if (idx == VIRTIO_CONFIG_IRQ_IDX) {
3432         return vhost_net_config_pending(get_vhost_net(nc->peer));
3433     }
3434     return vhost_net_virtqueue_pending(get_vhost_net(nc->peer), idx);
3435 }
3436 
3437 static void virtio_net_guest_notifier_mask(VirtIODevice *vdev, int idx,
3438                                            bool mask)
3439 {
3440     VirtIONet *n = VIRTIO_NET(vdev);
3441     NetClientState *nc;
3442     assert(n->vhost_started);
3443     if (!n->multiqueue && idx == 2) {
3444         /* Must guard against invalid features and bogus queue index
3445          * from being set by malicious guest, or penetrated through
3446          * buggy migration stream.
3447          */
3448         if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) {
3449             qemu_log_mask(LOG_GUEST_ERROR,
3450                           "%s: bogus vq index ignored\n", __func__);
3451             return;
3452         }
3453         nc = qemu_get_subqueue(n->nic, n->max_queue_pairs);
3454     } else {
3455         nc = qemu_get_subqueue(n->nic, vq2q(idx));
3456     }
3457     /*
3458      *Add the check for configure interrupt, Use VIRTIO_CONFIG_IRQ_IDX -1
3459      * as the macro of configure interrupt's IDX, If this driver does not
3460      * support, the function will return
3461      */
3462 
3463     if (idx == VIRTIO_CONFIG_IRQ_IDX) {
3464         vhost_net_config_mask(get_vhost_net(nc->peer), vdev, mask);
3465         return;
3466     }
3467     vhost_net_virtqueue_mask(get_vhost_net(nc->peer), vdev, idx, mask);
3468 }
3469 
3470 static void virtio_net_set_config_size(VirtIONet *n, uint64_t host_features)
3471 {
3472     virtio_add_feature(&host_features, VIRTIO_NET_F_MAC);
3473 
3474     n->config_size = virtio_get_config_size(&cfg_size_params, host_features);
3475 }
3476 
3477 void virtio_net_set_netclient_name(VirtIONet *n, const char *name,
3478                                    const char *type)
3479 {
3480     /*
3481      * The name can be NULL, the netclient name will be type.x.
3482      */
3483     assert(type != NULL);
3484 
3485     g_free(n->netclient_name);
3486     g_free(n->netclient_type);
3487     n->netclient_name = g_strdup(name);
3488     n->netclient_type = g_strdup(type);
3489 }
3490 
3491 static bool failover_unplug_primary(VirtIONet *n, DeviceState *dev)
3492 {
3493     HotplugHandler *hotplug_ctrl;
3494     PCIDevice *pci_dev;
3495     Error *err = NULL;
3496 
3497     hotplug_ctrl = qdev_get_hotplug_handler(dev);
3498     if (hotplug_ctrl) {
3499         pci_dev = PCI_DEVICE(dev);
3500         pci_dev->partially_hotplugged = true;
3501         hotplug_handler_unplug_request(hotplug_ctrl, dev, &err);
3502         if (err) {
3503             error_report_err(err);
3504             return false;
3505         }
3506     } else {
3507         return false;
3508     }
3509     return true;
3510 }
3511 
3512 static bool failover_replug_primary(VirtIONet *n, DeviceState *dev,
3513                                     Error **errp)
3514 {
3515     Error *err = NULL;
3516     HotplugHandler *hotplug_ctrl;
3517     PCIDevice *pdev = PCI_DEVICE(dev);
3518     BusState *primary_bus;
3519 
3520     if (!pdev->partially_hotplugged) {
3521         return true;
3522     }
3523     primary_bus = dev->parent_bus;
3524     if (!primary_bus) {
3525         error_setg(errp, "virtio_net: couldn't find primary bus");
3526         return false;
3527     }
3528     qdev_set_parent_bus(dev, primary_bus, &error_abort);
3529     qatomic_set(&n->failover_primary_hidden, false);
3530     hotplug_ctrl = qdev_get_hotplug_handler(dev);
3531     if (hotplug_ctrl) {
3532         hotplug_handler_pre_plug(hotplug_ctrl, dev, &err);
3533         if (err) {
3534             goto out;
3535         }
3536         hotplug_handler_plug(hotplug_ctrl, dev, &err);
3537     }
3538     pdev->partially_hotplugged = false;
3539 
3540 out:
3541     error_propagate(errp, err);
3542     return !err;
3543 }
3544 
3545 static void virtio_net_handle_migration_primary(VirtIONet *n, MigrationEvent *e)
3546 {
3547     bool should_be_hidden;
3548     Error *err = NULL;
3549     DeviceState *dev = failover_find_primary_device(n);
3550 
3551     if (!dev) {
3552         return;
3553     }
3554 
3555     should_be_hidden = qatomic_read(&n->failover_primary_hidden);
3556 
3557     if (e->type == MIG_EVENT_PRECOPY_SETUP && !should_be_hidden) {
3558         if (failover_unplug_primary(n, dev)) {
3559             vmstate_unregister(VMSTATE_IF(dev), qdev_get_vmsd(dev), dev);
3560             qapi_event_send_unplug_primary(dev->id);
3561             qatomic_set(&n->failover_primary_hidden, true);
3562         } else {
3563             warn_report("couldn't unplug primary device");
3564         }
3565     } else if (e->type == MIG_EVENT_PRECOPY_FAILED) {
3566         /* We already unplugged the device let's plug it back */
3567         if (!failover_replug_primary(n, dev, &err)) {
3568             if (err) {
3569                 error_report_err(err);
3570             }
3571         }
3572     }
3573 }
3574 
3575 static int virtio_net_migration_state_notifier(NotifierWithReturn *notifier,
3576                                                MigrationEvent *e, Error **errp)
3577 {
3578     VirtIONet *n = container_of(notifier, VirtIONet, migration_state);
3579     virtio_net_handle_migration_primary(n, e);
3580     return 0;
3581 }
3582 
3583 static bool failover_hide_primary_device(DeviceListener *listener,
3584                                          const QDict *device_opts,
3585                                          bool from_json,
3586                                          Error **errp)
3587 {
3588     VirtIONet *n = container_of(listener, VirtIONet, primary_listener);
3589     const char *standby_id;
3590 
3591     if (!device_opts) {
3592         return false;
3593     }
3594 
3595     if (!qdict_haskey(device_opts, "failover_pair_id")) {
3596         return false;
3597     }
3598 
3599     if (!qdict_haskey(device_opts, "id")) {
3600         error_setg(errp, "Device with failover_pair_id needs to have id");
3601         return false;
3602     }
3603 
3604     standby_id = qdict_get_str(device_opts, "failover_pair_id");
3605     if (g_strcmp0(standby_id, n->netclient_name) != 0) {
3606         return false;
3607     }
3608 
3609     /*
3610      * The hide helper can be called several times for a given device.
3611      * Check there is only one primary for a virtio-net device but
3612      * don't duplicate the qdict several times if it's called for the same
3613      * device.
3614      */
3615     if (n->primary_opts) {
3616         const char *old, *new;
3617         /* devices with failover_pair_id always have an id */
3618         old = qdict_get_str(n->primary_opts, "id");
3619         new = qdict_get_str(device_opts, "id");
3620         if (strcmp(old, new) != 0) {
3621             error_setg(errp, "Cannot attach more than one primary device to "
3622                        "'%s': '%s' and '%s'", n->netclient_name, old, new);
3623             return false;
3624         }
3625     } else {
3626         n->primary_opts = qdict_clone_shallow(device_opts);
3627         n->primary_opts_from_json = from_json;
3628     }
3629 
3630     /* failover_primary_hidden is set during feature negotiation */
3631     return qatomic_read(&n->failover_primary_hidden);
3632 }
3633 
3634 static void virtio_net_device_realize(DeviceState *dev, Error **errp)
3635 {
3636     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
3637     VirtIONet *n = VIRTIO_NET(dev);
3638     NetClientState *nc;
3639     int i;
3640 
3641     if (n->net_conf.mtu) {
3642         n->host_features |= (1ULL << VIRTIO_NET_F_MTU);
3643     }
3644 
3645     if (n->net_conf.duplex_str) {
3646         if (strncmp(n->net_conf.duplex_str, "half", 5) == 0) {
3647             n->net_conf.duplex = DUPLEX_HALF;
3648         } else if (strncmp(n->net_conf.duplex_str, "full", 5) == 0) {
3649             n->net_conf.duplex = DUPLEX_FULL;
3650         } else {
3651             error_setg(errp, "'duplex' must be 'half' or 'full'");
3652             return;
3653         }
3654         n->host_features |= (1ULL << VIRTIO_NET_F_SPEED_DUPLEX);
3655     } else {
3656         n->net_conf.duplex = DUPLEX_UNKNOWN;
3657     }
3658 
3659     if (n->net_conf.speed < SPEED_UNKNOWN) {
3660         error_setg(errp, "'speed' must be between 0 and INT_MAX");
3661         return;
3662     }
3663     if (n->net_conf.speed >= 0) {
3664         n->host_features |= (1ULL << VIRTIO_NET_F_SPEED_DUPLEX);
3665     }
3666 
3667     if (n->failover) {
3668         n->primary_listener.hide_device = failover_hide_primary_device;
3669         qatomic_set(&n->failover_primary_hidden, true);
3670         device_listener_register(&n->primary_listener);
3671         migration_add_notifier(&n->migration_state,
3672                                virtio_net_migration_state_notifier);
3673         n->host_features |= (1ULL << VIRTIO_NET_F_STANDBY);
3674     }
3675 
3676     virtio_net_set_config_size(n, n->host_features);
3677     virtio_init(vdev, VIRTIO_ID_NET, n->config_size);
3678 
3679     /*
3680      * We set a lower limit on RX queue size to what it always was.
3681      * Guests that want a smaller ring can always resize it without
3682      * help from us (using virtio 1 and up).
3683      */
3684     if (n->net_conf.rx_queue_size < VIRTIO_NET_RX_QUEUE_MIN_SIZE ||
3685         n->net_conf.rx_queue_size > VIRTQUEUE_MAX_SIZE ||
3686         !is_power_of_2(n->net_conf.rx_queue_size)) {
3687         error_setg(errp, "Invalid rx_queue_size (= %" PRIu16 "), "
3688                    "must be a power of 2 between %d and %d.",
3689                    n->net_conf.rx_queue_size, VIRTIO_NET_RX_QUEUE_MIN_SIZE,
3690                    VIRTQUEUE_MAX_SIZE);
3691         virtio_cleanup(vdev);
3692         return;
3693     }
3694 
3695     if (n->net_conf.tx_queue_size < VIRTIO_NET_TX_QUEUE_MIN_SIZE ||
3696         n->net_conf.tx_queue_size > virtio_net_max_tx_queue_size(n) ||
3697         !is_power_of_2(n->net_conf.tx_queue_size)) {
3698         error_setg(errp, "Invalid tx_queue_size (= %" PRIu16 "), "
3699                    "must be a power of 2 between %d and %d",
3700                    n->net_conf.tx_queue_size, VIRTIO_NET_TX_QUEUE_MIN_SIZE,
3701                    virtio_net_max_tx_queue_size(n));
3702         virtio_cleanup(vdev);
3703         return;
3704     }
3705 
3706     n->max_ncs = MAX(n->nic_conf.peers.queues, 1);
3707 
3708     /*
3709      * Figure out the datapath queue pairs since the backend could
3710      * provide control queue via peers as well.
3711      */
3712     if (n->nic_conf.peers.queues) {
3713         for (i = 0; i < n->max_ncs; i++) {
3714             if (n->nic_conf.peers.ncs[i]->is_datapath) {
3715                 ++n->max_queue_pairs;
3716             }
3717         }
3718     }
3719     n->max_queue_pairs = MAX(n->max_queue_pairs, 1);
3720 
3721     if (n->max_queue_pairs * 2 + 1 > VIRTIO_QUEUE_MAX) {
3722         error_setg(errp, "Invalid number of queue pairs (= %" PRIu32 "), "
3723                    "must be a positive integer less than %d.",
3724                    n->max_queue_pairs, (VIRTIO_QUEUE_MAX - 1) / 2);
3725         virtio_cleanup(vdev);
3726         return;
3727     }
3728     n->vqs = g_new0(VirtIONetQueue, n->max_queue_pairs);
3729     n->curr_queue_pairs = 1;
3730     n->tx_timeout = n->net_conf.txtimer;
3731 
3732     if (n->net_conf.tx && strcmp(n->net_conf.tx, "timer")
3733                        && strcmp(n->net_conf.tx, "bh")) {
3734         warn_report("virtio-net: "
3735                     "Unknown option tx=%s, valid options: \"timer\" \"bh\"",
3736                     n->net_conf.tx);
3737         error_printf("Defaulting to \"bh\"");
3738     }
3739 
3740     n->net_conf.tx_queue_size = MIN(virtio_net_max_tx_queue_size(n),
3741                                     n->net_conf.tx_queue_size);
3742 
3743     virtio_net_add_queue(n, 0);
3744 
3745     n->ctrl_vq = virtio_add_queue(vdev, 64, virtio_net_handle_ctrl);
3746     qemu_macaddr_default_if_unset(&n->nic_conf.macaddr);
3747     memcpy(&n->mac[0], &n->nic_conf.macaddr, sizeof(n->mac));
3748     n->status = VIRTIO_NET_S_LINK_UP;
3749     qemu_announce_timer_reset(&n->announce_timer, migrate_announce_params(),
3750                               QEMU_CLOCK_VIRTUAL,
3751                               virtio_net_announce_timer, n);
3752     n->announce_timer.round = 0;
3753 
3754     if (n->netclient_type) {
3755         /*
3756          * Happen when virtio_net_set_netclient_name has been called.
3757          */
3758         n->nic = qemu_new_nic(&net_virtio_info, &n->nic_conf,
3759                               n->netclient_type, n->netclient_name,
3760                               &dev->mem_reentrancy_guard, n);
3761     } else {
3762         n->nic = qemu_new_nic(&net_virtio_info, &n->nic_conf,
3763                               object_get_typename(OBJECT(dev)), dev->id,
3764                               &dev->mem_reentrancy_guard, n);
3765     }
3766 
3767     for (i = 0; i < n->max_queue_pairs; i++) {
3768         n->nic->ncs[i].do_not_pad = true;
3769     }
3770 
3771     peer_test_vnet_hdr(n);
3772     if (peer_has_vnet_hdr(n)) {
3773         n->host_hdr_len = sizeof(struct virtio_net_hdr);
3774     } else {
3775         n->host_hdr_len = 0;
3776     }
3777 
3778     qemu_format_nic_info_str(qemu_get_queue(n->nic), n->nic_conf.macaddr.a);
3779 
3780     n->vqs[0].tx_waiting = 0;
3781     n->tx_burst = n->net_conf.txburst;
3782     virtio_net_set_mrg_rx_bufs(n, 0, 0, 0);
3783     n->promisc = 1; /* for compatibility */
3784 
3785     n->mac_table.macs = g_malloc0(MAC_TABLE_ENTRIES * ETH_ALEN);
3786 
3787     n->vlans = g_malloc0(MAX_VLAN >> 3);
3788 
3789     nc = qemu_get_queue(n->nic);
3790     nc->rxfilter_notify_enabled = 1;
3791 
3792    if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_VDPA) {
3793         struct virtio_net_config netcfg = {};
3794         memcpy(&netcfg.mac, &n->nic_conf.macaddr, ETH_ALEN);
3795         vhost_net_set_config(get_vhost_net(nc->peer),
3796             (uint8_t *)&netcfg, 0, ETH_ALEN, VHOST_SET_CONFIG_TYPE_FRONTEND);
3797     }
3798     QTAILQ_INIT(&n->rsc_chains);
3799     n->qdev = dev;
3800 
3801     net_rx_pkt_init(&n->rx_pkt);
3802 
3803     if (virtio_has_feature(n->host_features, VIRTIO_NET_F_RSS)) {
3804         Error *err = NULL;
3805         if (!virtio_net_load_ebpf(n, &err)) {
3806             /*
3807              * If user explicitly gave QEMU RSS FDs to use, then
3808              * failing to use them must be considered a fatal
3809              * error. If no RSS FDs were provided, QEMU is trying
3810              * eBPF on a "best effort" basis only, so report a
3811              * warning and allow fallback to software RSS.
3812              */
3813             if (n->ebpf_rss_fds) {
3814                 error_propagate(errp, err);
3815             } else {
3816                 warn_report("unable to load eBPF RSS: %s",
3817                             error_get_pretty(err));
3818                 error_free(err);
3819             }
3820         }
3821     }
3822 }
3823 
3824 static void virtio_net_device_unrealize(DeviceState *dev)
3825 {
3826     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
3827     VirtIONet *n = VIRTIO_NET(dev);
3828     int i, max_queue_pairs;
3829 
3830     if (virtio_has_feature(n->host_features, VIRTIO_NET_F_RSS)) {
3831         virtio_net_unload_ebpf(n);
3832     }
3833 
3834     /* This will stop vhost backend if appropriate. */
3835     virtio_net_set_status(vdev, 0);
3836 
3837     g_free(n->netclient_name);
3838     n->netclient_name = NULL;
3839     g_free(n->netclient_type);
3840     n->netclient_type = NULL;
3841 
3842     g_free(n->mac_table.macs);
3843     g_free(n->vlans);
3844 
3845     if (n->failover) {
3846         qobject_unref(n->primary_opts);
3847         device_listener_unregister(&n->primary_listener);
3848         migration_remove_notifier(&n->migration_state);
3849     } else {
3850         assert(n->primary_opts == NULL);
3851     }
3852 
3853     max_queue_pairs = n->multiqueue ? n->max_queue_pairs : 1;
3854     for (i = 0; i < max_queue_pairs; i++) {
3855         virtio_net_del_queue(n, i);
3856     }
3857     /* delete also control vq */
3858     virtio_del_queue(vdev, max_queue_pairs * 2);
3859     qemu_announce_timer_del(&n->announce_timer, false);
3860     g_free(n->vqs);
3861     qemu_del_nic(n->nic);
3862     virtio_net_rsc_cleanup(n);
3863     g_free(n->rss_data.indirections_table);
3864     net_rx_pkt_uninit(n->rx_pkt);
3865     virtio_cleanup(vdev);
3866 }
3867 
3868 static void virtio_net_reset(VirtIODevice *vdev)
3869 {
3870     VirtIONet *n = VIRTIO_NET(vdev);
3871     int i;
3872 
3873     /* Reset back to compatibility mode */
3874     n->promisc = 1;
3875     n->allmulti = 0;
3876     n->alluni = 0;
3877     n->nomulti = 0;
3878     n->nouni = 0;
3879     n->nobcast = 0;
3880     /* multiqueue is disabled by default */
3881     n->curr_queue_pairs = 1;
3882     timer_del(n->announce_timer.tm);
3883     n->announce_timer.round = 0;
3884     n->status &= ~VIRTIO_NET_S_ANNOUNCE;
3885 
3886     /* Flush any MAC and VLAN filter table state */
3887     n->mac_table.in_use = 0;
3888     n->mac_table.first_multi = 0;
3889     n->mac_table.multi_overflow = 0;
3890     n->mac_table.uni_overflow = 0;
3891     memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
3892     memcpy(&n->mac[0], &n->nic->conf->macaddr, sizeof(n->mac));
3893     qemu_format_nic_info_str(qemu_get_queue(n->nic), n->mac);
3894     memset(n->vlans, 0, MAX_VLAN >> 3);
3895 
3896     /* Flush any async TX */
3897     for (i = 0;  i < n->max_queue_pairs; i++) {
3898         flush_or_purge_queued_packets(qemu_get_subqueue(n->nic, i));
3899     }
3900 
3901     virtio_net_disable_rss(n);
3902 }
3903 
3904 static void virtio_net_instance_init(Object *obj)
3905 {
3906     VirtIONet *n = VIRTIO_NET(obj);
3907 
3908     /*
3909      * The default config_size is sizeof(struct virtio_net_config).
3910      * Can be overridden with virtio_net_set_config_size.
3911      */
3912     n->config_size = sizeof(struct virtio_net_config);
3913     device_add_bootindex_property(obj, &n->nic_conf.bootindex,
3914                                   "bootindex", "/ethernet-phy@0",
3915                                   DEVICE(n));
3916 
3917     ebpf_rss_init(&n->ebpf_rss);
3918 }
3919 
3920 static int virtio_net_pre_save(void *opaque)
3921 {
3922     VirtIONet *n = opaque;
3923 
3924     /* At this point, backend must be stopped, otherwise
3925      * it might keep writing to memory. */
3926     assert(!n->vhost_started);
3927 
3928     return 0;
3929 }
3930 
3931 static bool primary_unplug_pending(void *opaque)
3932 {
3933     DeviceState *dev = opaque;
3934     DeviceState *primary;
3935     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
3936     VirtIONet *n = VIRTIO_NET(vdev);
3937 
3938     if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_STANDBY)) {
3939         return false;
3940     }
3941     primary = failover_find_primary_device(n);
3942     return primary ? primary->pending_deleted_event : false;
3943 }
3944 
3945 static bool dev_unplug_pending(void *opaque)
3946 {
3947     DeviceState *dev = opaque;
3948     VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(dev);
3949 
3950     return vdc->primary_unplug_pending(dev);
3951 }
3952 
3953 static struct vhost_dev *virtio_net_get_vhost(VirtIODevice *vdev)
3954 {
3955     VirtIONet *n = VIRTIO_NET(vdev);
3956     NetClientState *nc;
3957     struct vhost_net *net;
3958 
3959     if (!n->nic) {
3960         return NULL;
3961     }
3962 
3963     nc = qemu_get_queue(n->nic);
3964     if (!nc) {
3965         return NULL;
3966     }
3967 
3968     net = get_vhost_net(nc->peer);
3969     if (!net) {
3970         return NULL;
3971     }
3972 
3973     return &net->dev;
3974 }
3975 
3976 static const VMStateDescription vmstate_virtio_net = {
3977     .name = "virtio-net",
3978     .minimum_version_id = VIRTIO_NET_VM_VERSION,
3979     .version_id = VIRTIO_NET_VM_VERSION,
3980     .fields = (const VMStateField[]) {
3981         VMSTATE_VIRTIO_DEVICE,
3982         VMSTATE_END_OF_LIST()
3983     },
3984     .pre_save = virtio_net_pre_save,
3985     .dev_unplug_pending = dev_unplug_pending,
3986 };
3987 
3988 static Property virtio_net_properties[] = {
3989     DEFINE_PROP_BIT64("csum", VirtIONet, host_features,
3990                     VIRTIO_NET_F_CSUM, true),
3991     DEFINE_PROP_BIT64("guest_csum", VirtIONet, host_features,
3992                     VIRTIO_NET_F_GUEST_CSUM, true),
3993     DEFINE_PROP_BIT64("gso", VirtIONet, host_features, VIRTIO_NET_F_GSO, true),
3994     DEFINE_PROP_BIT64("guest_tso4", VirtIONet, host_features,
3995                     VIRTIO_NET_F_GUEST_TSO4, true),
3996     DEFINE_PROP_BIT64("guest_tso6", VirtIONet, host_features,
3997                     VIRTIO_NET_F_GUEST_TSO6, true),
3998     DEFINE_PROP_BIT64("guest_ecn", VirtIONet, host_features,
3999                     VIRTIO_NET_F_GUEST_ECN, true),
4000     DEFINE_PROP_BIT64("guest_ufo", VirtIONet, host_features,
4001                     VIRTIO_NET_F_GUEST_UFO, true),
4002     DEFINE_PROP_BIT64("guest_announce", VirtIONet, host_features,
4003                     VIRTIO_NET_F_GUEST_ANNOUNCE, true),
4004     DEFINE_PROP_BIT64("host_tso4", VirtIONet, host_features,
4005                     VIRTIO_NET_F_HOST_TSO4, true),
4006     DEFINE_PROP_BIT64("host_tso6", VirtIONet, host_features,
4007                     VIRTIO_NET_F_HOST_TSO6, true),
4008     DEFINE_PROP_BIT64("host_ecn", VirtIONet, host_features,
4009                     VIRTIO_NET_F_HOST_ECN, true),
4010     DEFINE_PROP_BIT64("host_ufo", VirtIONet, host_features,
4011                     VIRTIO_NET_F_HOST_UFO, true),
4012     DEFINE_PROP_BIT64("mrg_rxbuf", VirtIONet, host_features,
4013                     VIRTIO_NET_F_MRG_RXBUF, true),
4014     DEFINE_PROP_BIT64("status", VirtIONet, host_features,
4015                     VIRTIO_NET_F_STATUS, true),
4016     DEFINE_PROP_BIT64("ctrl_vq", VirtIONet, host_features,
4017                     VIRTIO_NET_F_CTRL_VQ, true),
4018     DEFINE_PROP_BIT64("ctrl_rx", VirtIONet, host_features,
4019                     VIRTIO_NET_F_CTRL_RX, true),
4020     DEFINE_PROP_BIT64("ctrl_vlan", VirtIONet, host_features,
4021                     VIRTIO_NET_F_CTRL_VLAN, true),
4022     DEFINE_PROP_BIT64("ctrl_rx_extra", VirtIONet, host_features,
4023                     VIRTIO_NET_F_CTRL_RX_EXTRA, true),
4024     DEFINE_PROP_BIT64("ctrl_mac_addr", VirtIONet, host_features,
4025                     VIRTIO_NET_F_CTRL_MAC_ADDR, true),
4026     DEFINE_PROP_BIT64("ctrl_guest_offloads", VirtIONet, host_features,
4027                     VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, true),
4028     DEFINE_PROP_BIT64("mq", VirtIONet, host_features, VIRTIO_NET_F_MQ, false),
4029     DEFINE_PROP_BIT64("rss", VirtIONet, host_features,
4030                     VIRTIO_NET_F_RSS, false),
4031     DEFINE_PROP_BIT64("hash", VirtIONet, host_features,
4032                     VIRTIO_NET_F_HASH_REPORT, false),
4033     DEFINE_PROP_ARRAY("ebpf-rss-fds", VirtIONet, nr_ebpf_rss_fds,
4034                       ebpf_rss_fds, qdev_prop_string, char*),
4035     DEFINE_PROP_BIT64("guest_rsc_ext", VirtIONet, host_features,
4036                     VIRTIO_NET_F_RSC_EXT, false),
4037     DEFINE_PROP_UINT32("rsc_interval", VirtIONet, rsc_timeout,
4038                        VIRTIO_NET_RSC_DEFAULT_INTERVAL),
4039     DEFINE_NIC_PROPERTIES(VirtIONet, nic_conf),
4040     DEFINE_PROP_UINT32("x-txtimer", VirtIONet, net_conf.txtimer,
4041                        TX_TIMER_INTERVAL),
4042     DEFINE_PROP_INT32("x-txburst", VirtIONet, net_conf.txburst, TX_BURST),
4043     DEFINE_PROP_STRING("tx", VirtIONet, net_conf.tx),
4044     DEFINE_PROP_UINT16("rx_queue_size", VirtIONet, net_conf.rx_queue_size,
4045                        VIRTIO_NET_RX_QUEUE_DEFAULT_SIZE),
4046     DEFINE_PROP_UINT16("tx_queue_size", VirtIONet, net_conf.tx_queue_size,
4047                        VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE),
4048     DEFINE_PROP_UINT16("host_mtu", VirtIONet, net_conf.mtu, 0),
4049     DEFINE_PROP_BOOL("x-mtu-bypass-backend", VirtIONet, mtu_bypass_backend,
4050                      true),
4051     DEFINE_PROP_INT32("speed", VirtIONet, net_conf.speed, SPEED_UNKNOWN),
4052     DEFINE_PROP_STRING("duplex", VirtIONet, net_conf.duplex_str),
4053     DEFINE_PROP_BOOL("failover", VirtIONet, failover, false),
4054     DEFINE_PROP_BIT64("guest_uso4", VirtIONet, host_features,
4055                       VIRTIO_NET_F_GUEST_USO4, true),
4056     DEFINE_PROP_BIT64("guest_uso6", VirtIONet, host_features,
4057                       VIRTIO_NET_F_GUEST_USO6, true),
4058     DEFINE_PROP_BIT64("host_uso", VirtIONet, host_features,
4059                       VIRTIO_NET_F_HOST_USO, true),
4060     DEFINE_PROP_END_OF_LIST(),
4061 };
4062 
4063 static void virtio_net_class_init(ObjectClass *klass, void *data)
4064 {
4065     DeviceClass *dc = DEVICE_CLASS(klass);
4066     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
4067 
4068     device_class_set_props(dc, virtio_net_properties);
4069     dc->vmsd = &vmstate_virtio_net;
4070     set_bit(DEVICE_CATEGORY_NETWORK, dc->categories);
4071     vdc->realize = virtio_net_device_realize;
4072     vdc->unrealize = virtio_net_device_unrealize;
4073     vdc->get_config = virtio_net_get_config;
4074     vdc->set_config = virtio_net_set_config;
4075     vdc->get_features = virtio_net_get_features;
4076     vdc->set_features = virtio_net_set_features;
4077     vdc->bad_features = virtio_net_bad_features;
4078     vdc->reset = virtio_net_reset;
4079     vdc->queue_reset = virtio_net_queue_reset;
4080     vdc->queue_enable = virtio_net_queue_enable;
4081     vdc->set_status = virtio_net_set_status;
4082     vdc->guest_notifier_mask = virtio_net_guest_notifier_mask;
4083     vdc->guest_notifier_pending = virtio_net_guest_notifier_pending;
4084     vdc->legacy_features |= (0x1 << VIRTIO_NET_F_GSO);
4085     vdc->pre_load_queues = virtio_net_pre_load_queues;
4086     vdc->post_load = virtio_net_post_load_virtio;
4087     vdc->vmsd = &vmstate_virtio_net_device;
4088     vdc->primary_unplug_pending = primary_unplug_pending;
4089     vdc->get_vhost = virtio_net_get_vhost;
4090     vdc->toggle_device_iotlb = vhost_toggle_device_iotlb;
4091 }
4092 
4093 static const TypeInfo virtio_net_info = {
4094     .name = TYPE_VIRTIO_NET,
4095     .parent = TYPE_VIRTIO_DEVICE,
4096     .instance_size = sizeof(VirtIONet),
4097     .instance_init = virtio_net_instance_init,
4098     .class_init = virtio_net_class_init,
4099 };
4100 
4101 static void virtio_register_types(void)
4102 {
4103     type_register_static(&virtio_net_info);
4104 }
4105 
4106 type_init(virtio_register_types)
4107