xref: /openbmc/qemu/hw/net/virtio-net.c (revision 719f0f60)
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/main-loop.h"
18 #include "qemu/module.h"
19 #include "hw/virtio/virtio.h"
20 #include "net/net.h"
21 #include "net/checksum.h"
22 #include "net/tap.h"
23 #include "qemu/error-report.h"
24 #include "qemu/timer.h"
25 #include "qemu/option.h"
26 #include "qemu/option_int.h"
27 #include "qemu/config-file.h"
28 #include "qapi/qmp/qdict.h"
29 #include "hw/virtio/virtio-net.h"
30 #include "net/vhost_net.h"
31 #include "net/announce.h"
32 #include "hw/virtio/virtio-bus.h"
33 #include "qapi/error.h"
34 #include "qapi/qapi-events-net.h"
35 #include "hw/qdev-properties.h"
36 #include "qapi/qapi-types-migration.h"
37 #include "qapi/qapi-events-migration.h"
38 #include "hw/virtio/virtio-access.h"
39 #include "migration/misc.h"
40 #include "standard-headers/linux/ethtool.h"
41 #include "sysemu/sysemu.h"
42 #include "trace.h"
43 #include "monitor/qdev.h"
44 #include "hw/pci/pci.h"
45 #include "net_rx_pkt.h"
46 #include "hw/virtio/vhost.h"
47 
48 #define VIRTIO_NET_VM_VERSION    11
49 
50 #define MAC_TABLE_ENTRIES    64
51 #define MAX_VLAN    (1 << 12)   /* Per 802.1Q definition */
52 
53 /* previously fixed value */
54 #define VIRTIO_NET_RX_QUEUE_DEFAULT_SIZE 256
55 #define VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE 256
56 
57 /* for now, only allow larger queues; with virtio-1, guest can downsize */
58 #define VIRTIO_NET_RX_QUEUE_MIN_SIZE VIRTIO_NET_RX_QUEUE_DEFAULT_SIZE
59 #define VIRTIO_NET_TX_QUEUE_MIN_SIZE VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE
60 
61 #define VIRTIO_NET_IP4_ADDR_SIZE   8        /* ipv4 saddr + daddr */
62 
63 #define VIRTIO_NET_TCP_FLAG         0x3F
64 #define VIRTIO_NET_TCP_HDR_LENGTH   0xF000
65 
66 /* IPv4 max payload, 16 bits in the header */
67 #define VIRTIO_NET_MAX_IP4_PAYLOAD (65535 - sizeof(struct ip_header))
68 #define VIRTIO_NET_MAX_TCP_PAYLOAD 65535
69 
70 /* header length value in ip header without option */
71 #define VIRTIO_NET_IP4_HEADER_LENGTH 5
72 
73 #define VIRTIO_NET_IP6_ADDR_SIZE   32      /* ipv6 saddr + daddr */
74 #define VIRTIO_NET_MAX_IP6_PAYLOAD VIRTIO_NET_MAX_TCP_PAYLOAD
75 
76 /* Purge coalesced packets timer interval, This value affects the performance
77    a lot, and should be tuned carefully, '300000'(300us) is the recommended
78    value to pass the WHQL test, '50000' can gain 2x netperf throughput with
79    tso/gso/gro 'off'. */
80 #define VIRTIO_NET_RSC_DEFAULT_INTERVAL 300000
81 
82 #define VIRTIO_NET_RSS_SUPPORTED_HASHES (VIRTIO_NET_RSS_HASH_TYPE_IPv4 | \
83                                          VIRTIO_NET_RSS_HASH_TYPE_TCPv4 | \
84                                          VIRTIO_NET_RSS_HASH_TYPE_UDPv4 | \
85                                          VIRTIO_NET_RSS_HASH_TYPE_IPv6 | \
86                                          VIRTIO_NET_RSS_HASH_TYPE_TCPv6 | \
87                                          VIRTIO_NET_RSS_HASH_TYPE_UDPv6 | \
88                                          VIRTIO_NET_RSS_HASH_TYPE_IP_EX | \
89                                          VIRTIO_NET_RSS_HASH_TYPE_TCP_EX | \
90                                          VIRTIO_NET_RSS_HASH_TYPE_UDP_EX)
91 
92 static const VirtIOFeature feature_sizes[] = {
93     {.flags = 1ULL << VIRTIO_NET_F_MAC,
94      .end = endof(struct virtio_net_config, mac)},
95     {.flags = 1ULL << VIRTIO_NET_F_STATUS,
96      .end = endof(struct virtio_net_config, status)},
97     {.flags = 1ULL << VIRTIO_NET_F_MQ,
98      .end = endof(struct virtio_net_config, max_virtqueue_pairs)},
99     {.flags = 1ULL << VIRTIO_NET_F_MTU,
100      .end = endof(struct virtio_net_config, mtu)},
101     {.flags = 1ULL << VIRTIO_NET_F_SPEED_DUPLEX,
102      .end = endof(struct virtio_net_config, duplex)},
103     {.flags = (1ULL << VIRTIO_NET_F_RSS) | (1ULL << VIRTIO_NET_F_HASH_REPORT),
104      .end = endof(struct virtio_net_config, supported_hash_types)},
105     {}
106 };
107 
108 static VirtIONetQueue *virtio_net_get_subqueue(NetClientState *nc)
109 {
110     VirtIONet *n = qemu_get_nic_opaque(nc);
111 
112     return &n->vqs[nc->queue_index];
113 }
114 
115 static int vq2q(int queue_index)
116 {
117     return queue_index / 2;
118 }
119 
120 /* TODO
121  * - we could suppress RX interrupt if we were so inclined.
122  */
123 
124 static void virtio_net_get_config(VirtIODevice *vdev, uint8_t *config)
125 {
126     VirtIONet *n = VIRTIO_NET(vdev);
127     struct virtio_net_config netcfg;
128     NetClientState *nc = qemu_get_queue(n->nic);
129     static const MACAddr zero = { .a = { 0, 0, 0, 0, 0, 0 } };
130 
131     int ret = 0;
132     memset(&netcfg, 0 , sizeof(struct virtio_net_config));
133     virtio_stw_p(vdev, &netcfg.status, n->status);
134     virtio_stw_p(vdev, &netcfg.max_virtqueue_pairs, n->max_queues);
135     virtio_stw_p(vdev, &netcfg.mtu, n->net_conf.mtu);
136     memcpy(netcfg.mac, n->mac, ETH_ALEN);
137     virtio_stl_p(vdev, &netcfg.speed, n->net_conf.speed);
138     netcfg.duplex = n->net_conf.duplex;
139     netcfg.rss_max_key_size = VIRTIO_NET_RSS_MAX_KEY_SIZE;
140     virtio_stw_p(vdev, &netcfg.rss_max_indirection_table_length,
141                  virtio_host_has_feature(vdev, VIRTIO_NET_F_RSS) ?
142                  VIRTIO_NET_RSS_MAX_TABLE_LEN : 1);
143     virtio_stl_p(vdev, &netcfg.supported_hash_types,
144                  VIRTIO_NET_RSS_SUPPORTED_HASHES);
145     memcpy(config, &netcfg, n->config_size);
146 
147     /*
148      * Is this VDPA? No peer means not VDPA: there's no way to
149      * disconnect/reconnect a VDPA peer.
150      */
151     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_VDPA) {
152         ret = vhost_net_get_config(get_vhost_net(nc->peer), (uint8_t *)&netcfg,
153                                    n->config_size);
154         if (ret != -1) {
155             /*
156              * Some NIC/kernel combinations present 0 as the mac address.  As
157              * that is not a legal address, try to proceed with the
158              * address from the QEMU command line in the hope that the
159              * address has been configured correctly elsewhere - just not
160              * reported by the device.
161              */
162             if (memcmp(&netcfg.mac, &zero, sizeof(zero)) == 0) {
163                 info_report("Zero hardware mac address detected. Ignoring.");
164                 memcpy(netcfg.mac, n->mac, ETH_ALEN);
165             }
166             memcpy(config, &netcfg, n->config_size);
167         }
168     }
169 }
170 
171 static void virtio_net_set_config(VirtIODevice *vdev, const uint8_t *config)
172 {
173     VirtIONet *n = VIRTIO_NET(vdev);
174     struct virtio_net_config netcfg = {};
175     NetClientState *nc = qemu_get_queue(n->nic);
176 
177     memcpy(&netcfg, config, n->config_size);
178 
179     if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR) &&
180         !virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1) &&
181         memcmp(netcfg.mac, n->mac, ETH_ALEN)) {
182         memcpy(n->mac, netcfg.mac, ETH_ALEN);
183         qemu_format_nic_info_str(qemu_get_queue(n->nic), n->mac);
184     }
185 
186     /*
187      * Is this VDPA? No peer means not VDPA: there's no way to
188      * disconnect/reconnect a VDPA peer.
189      */
190     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_VDPA) {
191         vhost_net_set_config(get_vhost_net(nc->peer),
192                              (uint8_t *)&netcfg, 0, n->config_size,
193                              VHOST_SET_CONFIG_TYPE_MASTER);
194       }
195 }
196 
197 static bool virtio_net_started(VirtIONet *n, uint8_t status)
198 {
199     VirtIODevice *vdev = VIRTIO_DEVICE(n);
200     return (status & VIRTIO_CONFIG_S_DRIVER_OK) &&
201         (n->status & VIRTIO_NET_S_LINK_UP) && vdev->vm_running;
202 }
203 
204 static void virtio_net_announce_notify(VirtIONet *net)
205 {
206     VirtIODevice *vdev = VIRTIO_DEVICE(net);
207     trace_virtio_net_announce_notify();
208 
209     net->status |= VIRTIO_NET_S_ANNOUNCE;
210     virtio_notify_config(vdev);
211 }
212 
213 static void virtio_net_announce_timer(void *opaque)
214 {
215     VirtIONet *n = opaque;
216     trace_virtio_net_announce_timer(n->announce_timer.round);
217 
218     n->announce_timer.round--;
219     virtio_net_announce_notify(n);
220 }
221 
222 static void virtio_net_announce(NetClientState *nc)
223 {
224     VirtIONet *n = qemu_get_nic_opaque(nc);
225     VirtIODevice *vdev = VIRTIO_DEVICE(n);
226 
227     /*
228      * Make sure the virtio migration announcement timer isn't running
229      * If it is, let it trigger announcement so that we do not cause
230      * confusion.
231      */
232     if (n->announce_timer.round) {
233         return;
234     }
235 
236     if (virtio_vdev_has_feature(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE) &&
237         virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) {
238             virtio_net_announce_notify(n);
239     }
240 }
241 
242 static void virtio_net_vhost_status(VirtIONet *n, uint8_t status)
243 {
244     VirtIODevice *vdev = VIRTIO_DEVICE(n);
245     NetClientState *nc = qemu_get_queue(n->nic);
246     int queues = n->multiqueue ? n->max_queues : 1;
247 
248     if (!get_vhost_net(nc->peer)) {
249         return;
250     }
251 
252     if ((virtio_net_started(n, status) && !nc->peer->link_down) ==
253         !!n->vhost_started) {
254         return;
255     }
256     if (!n->vhost_started) {
257         int r, i;
258 
259         if (n->needs_vnet_hdr_swap) {
260             error_report("backend does not support %s vnet headers; "
261                          "falling back on userspace virtio",
262                          virtio_is_big_endian(vdev) ? "BE" : "LE");
263             return;
264         }
265 
266         /* Any packets outstanding? Purge them to avoid touching rings
267          * when vhost is running.
268          */
269         for (i = 0;  i < queues; i++) {
270             NetClientState *qnc = qemu_get_subqueue(n->nic, i);
271 
272             /* Purge both directions: TX and RX. */
273             qemu_net_queue_purge(qnc->peer->incoming_queue, qnc);
274             qemu_net_queue_purge(qnc->incoming_queue, qnc->peer);
275         }
276 
277         if (virtio_has_feature(vdev->guest_features, VIRTIO_NET_F_MTU)) {
278             r = vhost_net_set_mtu(get_vhost_net(nc->peer), n->net_conf.mtu);
279             if (r < 0) {
280                 error_report("%uBytes MTU not supported by the backend",
281                              n->net_conf.mtu);
282 
283                 return;
284             }
285         }
286 
287         n->vhost_started = 1;
288         r = vhost_net_start(vdev, n->nic->ncs, queues);
289         if (r < 0) {
290             error_report("unable to start vhost net: %d: "
291                          "falling back on userspace virtio", -r);
292             n->vhost_started = 0;
293         }
294     } else {
295         vhost_net_stop(vdev, n->nic->ncs, queues);
296         n->vhost_started = 0;
297     }
298 }
299 
300 static int virtio_net_set_vnet_endian_one(VirtIODevice *vdev,
301                                           NetClientState *peer,
302                                           bool enable)
303 {
304     if (virtio_is_big_endian(vdev)) {
305         return qemu_set_vnet_be(peer, enable);
306     } else {
307         return qemu_set_vnet_le(peer, enable);
308     }
309 }
310 
311 static bool virtio_net_set_vnet_endian(VirtIODevice *vdev, NetClientState *ncs,
312                                        int queues, bool enable)
313 {
314     int i;
315 
316     for (i = 0; i < queues; i++) {
317         if (virtio_net_set_vnet_endian_one(vdev, ncs[i].peer, enable) < 0 &&
318             enable) {
319             while (--i >= 0) {
320                 virtio_net_set_vnet_endian_one(vdev, ncs[i].peer, false);
321             }
322 
323             return true;
324         }
325     }
326 
327     return false;
328 }
329 
330 static void virtio_net_vnet_endian_status(VirtIONet *n, uint8_t status)
331 {
332     VirtIODevice *vdev = VIRTIO_DEVICE(n);
333     int queues = n->multiqueue ? n->max_queues : 1;
334 
335     if (virtio_net_started(n, status)) {
336         /* Before using the device, we tell the network backend about the
337          * endianness to use when parsing vnet headers. If the backend
338          * can't do it, we fallback onto fixing the headers in the core
339          * virtio-net code.
340          */
341         n->needs_vnet_hdr_swap = virtio_net_set_vnet_endian(vdev, n->nic->ncs,
342                                                             queues, true);
343     } else if (virtio_net_started(n, vdev->status)) {
344         /* After using the device, we need to reset the network backend to
345          * the default (guest native endianness), otherwise the guest may
346          * lose network connectivity if it is rebooted into a different
347          * endianness.
348          */
349         virtio_net_set_vnet_endian(vdev, n->nic->ncs, queues, false);
350     }
351 }
352 
353 static void virtio_net_drop_tx_queue_data(VirtIODevice *vdev, VirtQueue *vq)
354 {
355     unsigned int dropped = virtqueue_drop_all(vq);
356     if (dropped) {
357         virtio_notify(vdev, vq);
358     }
359 }
360 
361 static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status)
362 {
363     VirtIONet *n = VIRTIO_NET(vdev);
364     VirtIONetQueue *q;
365     int i;
366     uint8_t queue_status;
367 
368     virtio_net_vnet_endian_status(n, status);
369     virtio_net_vhost_status(n, status);
370 
371     for (i = 0; i < n->max_queues; i++) {
372         NetClientState *ncs = qemu_get_subqueue(n->nic, i);
373         bool queue_started;
374         q = &n->vqs[i];
375 
376         if ((!n->multiqueue && i != 0) || i >= n->curr_queues) {
377             queue_status = 0;
378         } else {
379             queue_status = status;
380         }
381         queue_started =
382             virtio_net_started(n, queue_status) && !n->vhost_started;
383 
384         if (queue_started) {
385             qemu_flush_queued_packets(ncs);
386         }
387 
388         if (!q->tx_waiting) {
389             continue;
390         }
391 
392         if (queue_started) {
393             if (q->tx_timer) {
394                 timer_mod(q->tx_timer,
395                                qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + n->tx_timeout);
396             } else {
397                 qemu_bh_schedule(q->tx_bh);
398             }
399         } else {
400             if (q->tx_timer) {
401                 timer_del(q->tx_timer);
402             } else {
403                 qemu_bh_cancel(q->tx_bh);
404             }
405             if ((n->status & VIRTIO_NET_S_LINK_UP) == 0 &&
406                 (queue_status & VIRTIO_CONFIG_S_DRIVER_OK) &&
407                 vdev->vm_running) {
408                 /* if tx is waiting we are likely have some packets in tx queue
409                  * and disabled notification */
410                 q->tx_waiting = 0;
411                 virtio_queue_set_notification(q->tx_vq, 1);
412                 virtio_net_drop_tx_queue_data(vdev, q->tx_vq);
413             }
414         }
415     }
416 }
417 
418 static void virtio_net_set_link_status(NetClientState *nc)
419 {
420     VirtIONet *n = qemu_get_nic_opaque(nc);
421     VirtIODevice *vdev = VIRTIO_DEVICE(n);
422     uint16_t old_status = n->status;
423 
424     if (nc->link_down)
425         n->status &= ~VIRTIO_NET_S_LINK_UP;
426     else
427         n->status |= VIRTIO_NET_S_LINK_UP;
428 
429     if (n->status != old_status)
430         virtio_notify_config(vdev);
431 
432     virtio_net_set_status(vdev, vdev->status);
433 }
434 
435 static void rxfilter_notify(NetClientState *nc)
436 {
437     VirtIONet *n = qemu_get_nic_opaque(nc);
438 
439     if (nc->rxfilter_notify_enabled) {
440         char *path = object_get_canonical_path(OBJECT(n->qdev));
441         qapi_event_send_nic_rx_filter_changed(!!n->netclient_name,
442                                               n->netclient_name, path);
443         g_free(path);
444 
445         /* disable event notification to avoid events flooding */
446         nc->rxfilter_notify_enabled = 0;
447     }
448 }
449 
450 static intList *get_vlan_table(VirtIONet *n)
451 {
452     intList *list;
453     int i, j;
454 
455     list = NULL;
456     for (i = 0; i < MAX_VLAN >> 5; i++) {
457         for (j = 0; n->vlans[i] && j <= 0x1f; j++) {
458             if (n->vlans[i] & (1U << j)) {
459                 QAPI_LIST_PREPEND(list, (i << 5) + j);
460             }
461         }
462     }
463 
464     return list;
465 }
466 
467 static RxFilterInfo *virtio_net_query_rxfilter(NetClientState *nc)
468 {
469     VirtIONet *n = qemu_get_nic_opaque(nc);
470     VirtIODevice *vdev = VIRTIO_DEVICE(n);
471     RxFilterInfo *info;
472     strList *str_list;
473     int i;
474 
475     info = g_malloc0(sizeof(*info));
476     info->name = g_strdup(nc->name);
477     info->promiscuous = n->promisc;
478 
479     if (n->nouni) {
480         info->unicast = RX_STATE_NONE;
481     } else if (n->alluni) {
482         info->unicast = RX_STATE_ALL;
483     } else {
484         info->unicast = RX_STATE_NORMAL;
485     }
486 
487     if (n->nomulti) {
488         info->multicast = RX_STATE_NONE;
489     } else if (n->allmulti) {
490         info->multicast = RX_STATE_ALL;
491     } else {
492         info->multicast = RX_STATE_NORMAL;
493     }
494 
495     info->broadcast_allowed = n->nobcast;
496     info->multicast_overflow = n->mac_table.multi_overflow;
497     info->unicast_overflow = n->mac_table.uni_overflow;
498 
499     info->main_mac = qemu_mac_strdup_printf(n->mac);
500 
501     str_list = NULL;
502     for (i = 0; i < n->mac_table.first_multi; i++) {
503         QAPI_LIST_PREPEND(str_list,
504                       qemu_mac_strdup_printf(n->mac_table.macs + i * ETH_ALEN));
505     }
506     info->unicast_table = str_list;
507 
508     str_list = NULL;
509     for (i = n->mac_table.first_multi; i < n->mac_table.in_use; i++) {
510         QAPI_LIST_PREPEND(str_list,
511                       qemu_mac_strdup_printf(n->mac_table.macs + i * ETH_ALEN));
512     }
513     info->multicast_table = str_list;
514     info->vlan_table = get_vlan_table(n);
515 
516     if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_VLAN)) {
517         info->vlan = RX_STATE_ALL;
518     } else if (!info->vlan_table) {
519         info->vlan = RX_STATE_NONE;
520     } else {
521         info->vlan = RX_STATE_NORMAL;
522     }
523 
524     /* enable event notification after query */
525     nc->rxfilter_notify_enabled = 1;
526 
527     return info;
528 }
529 
530 static void virtio_net_reset(VirtIODevice *vdev)
531 {
532     VirtIONet *n = VIRTIO_NET(vdev);
533     int i;
534 
535     /* Reset back to compatibility mode */
536     n->promisc = 1;
537     n->allmulti = 0;
538     n->alluni = 0;
539     n->nomulti = 0;
540     n->nouni = 0;
541     n->nobcast = 0;
542     /* multiqueue is disabled by default */
543     n->curr_queues = 1;
544     timer_del(n->announce_timer.tm);
545     n->announce_timer.round = 0;
546     n->status &= ~VIRTIO_NET_S_ANNOUNCE;
547 
548     /* Flush any MAC and VLAN filter table state */
549     n->mac_table.in_use = 0;
550     n->mac_table.first_multi = 0;
551     n->mac_table.multi_overflow = 0;
552     n->mac_table.uni_overflow = 0;
553     memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
554     memcpy(&n->mac[0], &n->nic->conf->macaddr, sizeof(n->mac));
555     qemu_format_nic_info_str(qemu_get_queue(n->nic), n->mac);
556     memset(n->vlans, 0, MAX_VLAN >> 3);
557 
558     /* Flush any async TX */
559     for (i = 0;  i < n->max_queues; i++) {
560         NetClientState *nc = qemu_get_subqueue(n->nic, i);
561 
562         if (nc->peer) {
563             qemu_flush_or_purge_queued_packets(nc->peer, true);
564             assert(!virtio_net_get_subqueue(nc)->async_tx.elem);
565         }
566     }
567 }
568 
569 static void peer_test_vnet_hdr(VirtIONet *n)
570 {
571     NetClientState *nc = qemu_get_queue(n->nic);
572     if (!nc->peer) {
573         return;
574     }
575 
576     n->has_vnet_hdr = qemu_has_vnet_hdr(nc->peer);
577 }
578 
579 static int peer_has_vnet_hdr(VirtIONet *n)
580 {
581     return n->has_vnet_hdr;
582 }
583 
584 static int peer_has_ufo(VirtIONet *n)
585 {
586     if (!peer_has_vnet_hdr(n))
587         return 0;
588 
589     n->has_ufo = qemu_has_ufo(qemu_get_queue(n->nic)->peer);
590 
591     return n->has_ufo;
592 }
593 
594 static void virtio_net_set_mrg_rx_bufs(VirtIONet *n, int mergeable_rx_bufs,
595                                        int version_1, int hash_report)
596 {
597     int i;
598     NetClientState *nc;
599 
600     n->mergeable_rx_bufs = mergeable_rx_bufs;
601 
602     if (version_1) {
603         n->guest_hdr_len = hash_report ?
604             sizeof(struct virtio_net_hdr_v1_hash) :
605             sizeof(struct virtio_net_hdr_mrg_rxbuf);
606         n->rss_data.populate_hash = !!hash_report;
607     } else {
608         n->guest_hdr_len = n->mergeable_rx_bufs ?
609             sizeof(struct virtio_net_hdr_mrg_rxbuf) :
610             sizeof(struct virtio_net_hdr);
611     }
612 
613     for (i = 0; i < n->max_queues; i++) {
614         nc = qemu_get_subqueue(n->nic, i);
615 
616         if (peer_has_vnet_hdr(n) &&
617             qemu_has_vnet_hdr_len(nc->peer, n->guest_hdr_len)) {
618             qemu_set_vnet_hdr_len(nc->peer, n->guest_hdr_len);
619             n->host_hdr_len = n->guest_hdr_len;
620         }
621     }
622 }
623 
624 static int virtio_net_max_tx_queue_size(VirtIONet *n)
625 {
626     NetClientState *peer = n->nic_conf.peers.ncs[0];
627 
628     /*
629      * Backends other than vhost-user don't support max queue size.
630      */
631     if (!peer) {
632         return VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE;
633     }
634 
635     if (peer->info->type != NET_CLIENT_DRIVER_VHOST_USER) {
636         return VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE;
637     }
638 
639     return VIRTQUEUE_MAX_SIZE;
640 }
641 
642 static int peer_attach(VirtIONet *n, int index)
643 {
644     NetClientState *nc = qemu_get_subqueue(n->nic, index);
645 
646     if (!nc->peer) {
647         return 0;
648     }
649 
650     if (nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
651         vhost_set_vring_enable(nc->peer, 1);
652     }
653 
654     if (nc->peer->info->type != NET_CLIENT_DRIVER_TAP) {
655         return 0;
656     }
657 
658     if (n->max_queues == 1) {
659         return 0;
660     }
661 
662     return tap_enable(nc->peer);
663 }
664 
665 static int peer_detach(VirtIONet *n, int index)
666 {
667     NetClientState *nc = qemu_get_subqueue(n->nic, index);
668 
669     if (!nc->peer) {
670         return 0;
671     }
672 
673     if (nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
674         vhost_set_vring_enable(nc->peer, 0);
675     }
676 
677     if (nc->peer->info->type !=  NET_CLIENT_DRIVER_TAP) {
678         return 0;
679     }
680 
681     return tap_disable(nc->peer);
682 }
683 
684 static void virtio_net_set_queues(VirtIONet *n)
685 {
686     int i;
687     int r;
688 
689     if (n->nic->peer_deleted) {
690         return;
691     }
692 
693     for (i = 0; i < n->max_queues; i++) {
694         if (i < n->curr_queues) {
695             r = peer_attach(n, i);
696             assert(!r);
697         } else {
698             r = peer_detach(n, i);
699             assert(!r);
700         }
701     }
702 }
703 
704 static void virtio_net_set_multiqueue(VirtIONet *n, int multiqueue);
705 
706 static uint64_t virtio_net_get_features(VirtIODevice *vdev, uint64_t features,
707                                         Error **errp)
708 {
709     VirtIONet *n = VIRTIO_NET(vdev);
710     NetClientState *nc = qemu_get_queue(n->nic);
711 
712     /* Firstly sync all virtio-net possible supported features */
713     features |= n->host_features;
714 
715     virtio_add_feature(&features, VIRTIO_NET_F_MAC);
716 
717     if (!peer_has_vnet_hdr(n)) {
718         virtio_clear_feature(&features, VIRTIO_NET_F_CSUM);
719         virtio_clear_feature(&features, VIRTIO_NET_F_HOST_TSO4);
720         virtio_clear_feature(&features, VIRTIO_NET_F_HOST_TSO6);
721         virtio_clear_feature(&features, VIRTIO_NET_F_HOST_ECN);
722 
723         virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_CSUM);
724         virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_TSO4);
725         virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_TSO6);
726         virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_ECN);
727 
728         virtio_clear_feature(&features, VIRTIO_NET_F_HASH_REPORT);
729     }
730 
731     if (!peer_has_vnet_hdr(n) || !peer_has_ufo(n)) {
732         virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_UFO);
733         virtio_clear_feature(&features, VIRTIO_NET_F_HOST_UFO);
734     }
735 
736     if (!get_vhost_net(nc->peer)) {
737         return features;
738     }
739 
740     if (!ebpf_rss_is_loaded(&n->ebpf_rss)) {
741         virtio_clear_feature(&features, VIRTIO_NET_F_RSS);
742     }
743     features = vhost_net_get_features(get_vhost_net(nc->peer), features);
744     vdev->backend_features = features;
745 
746     if (n->mtu_bypass_backend &&
747             (n->host_features & 1ULL << VIRTIO_NET_F_MTU)) {
748         features |= (1ULL << VIRTIO_NET_F_MTU);
749     }
750 
751     return features;
752 }
753 
754 static uint64_t virtio_net_bad_features(VirtIODevice *vdev)
755 {
756     uint64_t features = 0;
757 
758     /* Linux kernel 2.6.25.  It understood MAC (as everyone must),
759      * but also these: */
760     virtio_add_feature(&features, VIRTIO_NET_F_MAC);
761     virtio_add_feature(&features, VIRTIO_NET_F_CSUM);
762     virtio_add_feature(&features, VIRTIO_NET_F_HOST_TSO4);
763     virtio_add_feature(&features, VIRTIO_NET_F_HOST_TSO6);
764     virtio_add_feature(&features, VIRTIO_NET_F_HOST_ECN);
765 
766     return features;
767 }
768 
769 static void virtio_net_apply_guest_offloads(VirtIONet *n)
770 {
771     qemu_set_offload(qemu_get_queue(n->nic)->peer,
772             !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_CSUM)),
773             !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_TSO4)),
774             !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_TSO6)),
775             !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_ECN)),
776             !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_UFO)));
777 }
778 
779 static uint64_t virtio_net_guest_offloads_by_features(uint32_t features)
780 {
781     static const uint64_t guest_offloads_mask =
782         (1ULL << VIRTIO_NET_F_GUEST_CSUM) |
783         (1ULL << VIRTIO_NET_F_GUEST_TSO4) |
784         (1ULL << VIRTIO_NET_F_GUEST_TSO6) |
785         (1ULL << VIRTIO_NET_F_GUEST_ECN)  |
786         (1ULL << VIRTIO_NET_F_GUEST_UFO);
787 
788     return guest_offloads_mask & features;
789 }
790 
791 static inline uint64_t virtio_net_supported_guest_offloads(VirtIONet *n)
792 {
793     VirtIODevice *vdev = VIRTIO_DEVICE(n);
794     return virtio_net_guest_offloads_by_features(vdev->guest_features);
795 }
796 
797 typedef struct {
798     VirtIONet *n;
799     char *id;
800 } FailoverId;
801 
802 /**
803  * Set the id of the failover primary device
804  *
805  * @opaque: FailoverId to setup
806  * @opts: opts for device we are handling
807  * @errp: returns an error if this function fails
808  */
809 static int failover_set_primary(void *opaque, QemuOpts *opts, Error **errp)
810 {
811     FailoverId *fid = opaque;
812     const char *standby_id = qemu_opt_get(opts, "failover_pair_id");
813 
814     if (g_strcmp0(standby_id, fid->n->netclient_name) == 0) {
815         fid->id = g_strdup(opts->id);
816         return 1;
817     }
818 
819     return 0;
820 }
821 
822 /**
823  * Find the primary device id for this failover virtio-net
824  *
825  * @n: VirtIONet device
826  * @errp: returns an error if this function fails
827  */
828 static char *failover_find_primary_device_id(VirtIONet *n)
829 {
830     Error *err = NULL;
831     FailoverId fid;
832 
833     fid.n = n;
834     if (!qemu_opts_foreach(qemu_find_opts("device"),
835                            failover_set_primary, &fid, &err)) {
836         return NULL;
837     }
838     return fid.id;
839 }
840 
841 /**
842  * Find the primary device for this failover virtio-net
843  *
844  * @n: VirtIONet device
845  * @errp: returns an error if this function fails
846  */
847 static DeviceState *failover_find_primary_device(VirtIONet *n)
848 {
849     char *id = failover_find_primary_device_id(n);
850 
851     if (!id) {
852         return NULL;
853     }
854 
855     return qdev_find_recursive(sysbus_get_default(), id);
856 }
857 
858 static void failover_add_primary(VirtIONet *n, Error **errp)
859 {
860     Error *err = NULL;
861     QemuOpts *opts;
862     char *id;
863     DeviceState *dev = failover_find_primary_device(n);
864 
865     if (dev) {
866         return;
867     }
868 
869     id = failover_find_primary_device_id(n);
870     if (!id) {
871         error_setg(errp, "Primary device not found");
872         error_append_hint(errp, "Virtio-net failover will not work. Make "
873                           "sure primary device has parameter"
874                           " failover_pair_id=%s\n", n->netclient_name);
875         return;
876     }
877     opts = qemu_opts_find(qemu_find_opts("device"), id);
878     g_assert(opts); /* cannot be NULL because id was found using opts list */
879     dev = qdev_device_add(opts, &err);
880     if (err) {
881         qemu_opts_del(opts);
882     } else {
883         object_unref(OBJECT(dev));
884     }
885     error_propagate(errp, err);
886 }
887 
888 static void virtio_net_set_features(VirtIODevice *vdev, uint64_t features)
889 {
890     VirtIONet *n = VIRTIO_NET(vdev);
891     Error *err = NULL;
892     int i;
893 
894     if (n->mtu_bypass_backend &&
895             !virtio_has_feature(vdev->backend_features, VIRTIO_NET_F_MTU)) {
896         features &= ~(1ULL << VIRTIO_NET_F_MTU);
897     }
898 
899     virtio_net_set_multiqueue(n,
900                               virtio_has_feature(features, VIRTIO_NET_F_RSS) ||
901                               virtio_has_feature(features, VIRTIO_NET_F_MQ));
902 
903     virtio_net_set_mrg_rx_bufs(n,
904                                virtio_has_feature(features,
905                                                   VIRTIO_NET_F_MRG_RXBUF),
906                                virtio_has_feature(features,
907                                                   VIRTIO_F_VERSION_1),
908                                virtio_has_feature(features,
909                                                   VIRTIO_NET_F_HASH_REPORT));
910 
911     n->rsc4_enabled = virtio_has_feature(features, VIRTIO_NET_F_RSC_EXT) &&
912         virtio_has_feature(features, VIRTIO_NET_F_GUEST_TSO4);
913     n->rsc6_enabled = virtio_has_feature(features, VIRTIO_NET_F_RSC_EXT) &&
914         virtio_has_feature(features, VIRTIO_NET_F_GUEST_TSO6);
915     n->rss_data.redirect = virtio_has_feature(features, VIRTIO_NET_F_RSS);
916 
917     if (n->has_vnet_hdr) {
918         n->curr_guest_offloads =
919             virtio_net_guest_offloads_by_features(features);
920         virtio_net_apply_guest_offloads(n);
921     }
922 
923     for (i = 0;  i < n->max_queues; i++) {
924         NetClientState *nc = qemu_get_subqueue(n->nic, i);
925 
926         if (!get_vhost_net(nc->peer)) {
927             continue;
928         }
929         vhost_net_ack_features(get_vhost_net(nc->peer), features);
930     }
931 
932     if (virtio_has_feature(features, VIRTIO_NET_F_CTRL_VLAN)) {
933         memset(n->vlans, 0, MAX_VLAN >> 3);
934     } else {
935         memset(n->vlans, 0xff, MAX_VLAN >> 3);
936     }
937 
938     if (virtio_has_feature(features, VIRTIO_NET_F_STANDBY)) {
939         qapi_event_send_failover_negotiated(n->netclient_name);
940         qatomic_set(&n->failover_primary_hidden, false);
941         failover_add_primary(n, &err);
942         if (err) {
943             warn_report_err(err);
944         }
945     }
946 }
947 
948 static int virtio_net_handle_rx_mode(VirtIONet *n, uint8_t cmd,
949                                      struct iovec *iov, unsigned int iov_cnt)
950 {
951     uint8_t on;
952     size_t s;
953     NetClientState *nc = qemu_get_queue(n->nic);
954 
955     s = iov_to_buf(iov, iov_cnt, 0, &on, sizeof(on));
956     if (s != sizeof(on)) {
957         return VIRTIO_NET_ERR;
958     }
959 
960     if (cmd == VIRTIO_NET_CTRL_RX_PROMISC) {
961         n->promisc = on;
962     } else if (cmd == VIRTIO_NET_CTRL_RX_ALLMULTI) {
963         n->allmulti = on;
964     } else if (cmd == VIRTIO_NET_CTRL_RX_ALLUNI) {
965         n->alluni = on;
966     } else if (cmd == VIRTIO_NET_CTRL_RX_NOMULTI) {
967         n->nomulti = on;
968     } else if (cmd == VIRTIO_NET_CTRL_RX_NOUNI) {
969         n->nouni = on;
970     } else if (cmd == VIRTIO_NET_CTRL_RX_NOBCAST) {
971         n->nobcast = on;
972     } else {
973         return VIRTIO_NET_ERR;
974     }
975 
976     rxfilter_notify(nc);
977 
978     return VIRTIO_NET_OK;
979 }
980 
981 static int virtio_net_handle_offloads(VirtIONet *n, uint8_t cmd,
982                                      struct iovec *iov, unsigned int iov_cnt)
983 {
984     VirtIODevice *vdev = VIRTIO_DEVICE(n);
985     uint64_t offloads;
986     size_t s;
987 
988     if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)) {
989         return VIRTIO_NET_ERR;
990     }
991 
992     s = iov_to_buf(iov, iov_cnt, 0, &offloads, sizeof(offloads));
993     if (s != sizeof(offloads)) {
994         return VIRTIO_NET_ERR;
995     }
996 
997     if (cmd == VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET) {
998         uint64_t supported_offloads;
999 
1000         offloads = virtio_ldq_p(vdev, &offloads);
1001 
1002         if (!n->has_vnet_hdr) {
1003             return VIRTIO_NET_ERR;
1004         }
1005 
1006         n->rsc4_enabled = virtio_has_feature(offloads, VIRTIO_NET_F_RSC_EXT) &&
1007             virtio_has_feature(offloads, VIRTIO_NET_F_GUEST_TSO4);
1008         n->rsc6_enabled = virtio_has_feature(offloads, VIRTIO_NET_F_RSC_EXT) &&
1009             virtio_has_feature(offloads, VIRTIO_NET_F_GUEST_TSO6);
1010         virtio_clear_feature(&offloads, VIRTIO_NET_F_RSC_EXT);
1011 
1012         supported_offloads = virtio_net_supported_guest_offloads(n);
1013         if (offloads & ~supported_offloads) {
1014             return VIRTIO_NET_ERR;
1015         }
1016 
1017         n->curr_guest_offloads = offloads;
1018         virtio_net_apply_guest_offloads(n);
1019 
1020         return VIRTIO_NET_OK;
1021     } else {
1022         return VIRTIO_NET_ERR;
1023     }
1024 }
1025 
1026 static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd,
1027                                  struct iovec *iov, unsigned int iov_cnt)
1028 {
1029     VirtIODevice *vdev = VIRTIO_DEVICE(n);
1030     struct virtio_net_ctrl_mac mac_data;
1031     size_t s;
1032     NetClientState *nc = qemu_get_queue(n->nic);
1033 
1034     if (cmd == VIRTIO_NET_CTRL_MAC_ADDR_SET) {
1035         if (iov_size(iov, iov_cnt) != sizeof(n->mac)) {
1036             return VIRTIO_NET_ERR;
1037         }
1038         s = iov_to_buf(iov, iov_cnt, 0, &n->mac, sizeof(n->mac));
1039         assert(s == sizeof(n->mac));
1040         qemu_format_nic_info_str(qemu_get_queue(n->nic), n->mac);
1041         rxfilter_notify(nc);
1042 
1043         return VIRTIO_NET_OK;
1044     }
1045 
1046     if (cmd != VIRTIO_NET_CTRL_MAC_TABLE_SET) {
1047         return VIRTIO_NET_ERR;
1048     }
1049 
1050     int in_use = 0;
1051     int first_multi = 0;
1052     uint8_t uni_overflow = 0;
1053     uint8_t multi_overflow = 0;
1054     uint8_t *macs = g_malloc0(MAC_TABLE_ENTRIES * ETH_ALEN);
1055 
1056     s = iov_to_buf(iov, iov_cnt, 0, &mac_data.entries,
1057                    sizeof(mac_data.entries));
1058     mac_data.entries = virtio_ldl_p(vdev, &mac_data.entries);
1059     if (s != sizeof(mac_data.entries)) {
1060         goto error;
1061     }
1062     iov_discard_front(&iov, &iov_cnt, s);
1063 
1064     if (mac_data.entries * ETH_ALEN > iov_size(iov, iov_cnt)) {
1065         goto error;
1066     }
1067 
1068     if (mac_data.entries <= MAC_TABLE_ENTRIES) {
1069         s = iov_to_buf(iov, iov_cnt, 0, macs,
1070                        mac_data.entries * ETH_ALEN);
1071         if (s != mac_data.entries * ETH_ALEN) {
1072             goto error;
1073         }
1074         in_use += mac_data.entries;
1075     } else {
1076         uni_overflow = 1;
1077     }
1078 
1079     iov_discard_front(&iov, &iov_cnt, mac_data.entries * ETH_ALEN);
1080 
1081     first_multi = in_use;
1082 
1083     s = iov_to_buf(iov, iov_cnt, 0, &mac_data.entries,
1084                    sizeof(mac_data.entries));
1085     mac_data.entries = virtio_ldl_p(vdev, &mac_data.entries);
1086     if (s != sizeof(mac_data.entries)) {
1087         goto error;
1088     }
1089 
1090     iov_discard_front(&iov, &iov_cnt, s);
1091 
1092     if (mac_data.entries * ETH_ALEN != iov_size(iov, iov_cnt)) {
1093         goto error;
1094     }
1095 
1096     if (mac_data.entries <= MAC_TABLE_ENTRIES - in_use) {
1097         s = iov_to_buf(iov, iov_cnt, 0, &macs[in_use * ETH_ALEN],
1098                        mac_data.entries * ETH_ALEN);
1099         if (s != mac_data.entries * ETH_ALEN) {
1100             goto error;
1101         }
1102         in_use += mac_data.entries;
1103     } else {
1104         multi_overflow = 1;
1105     }
1106 
1107     n->mac_table.in_use = in_use;
1108     n->mac_table.first_multi = first_multi;
1109     n->mac_table.uni_overflow = uni_overflow;
1110     n->mac_table.multi_overflow = multi_overflow;
1111     memcpy(n->mac_table.macs, macs, MAC_TABLE_ENTRIES * ETH_ALEN);
1112     g_free(macs);
1113     rxfilter_notify(nc);
1114 
1115     return VIRTIO_NET_OK;
1116 
1117 error:
1118     g_free(macs);
1119     return VIRTIO_NET_ERR;
1120 }
1121 
1122 static int virtio_net_handle_vlan_table(VirtIONet *n, uint8_t cmd,
1123                                         struct iovec *iov, unsigned int iov_cnt)
1124 {
1125     VirtIODevice *vdev = VIRTIO_DEVICE(n);
1126     uint16_t vid;
1127     size_t s;
1128     NetClientState *nc = qemu_get_queue(n->nic);
1129 
1130     s = iov_to_buf(iov, iov_cnt, 0, &vid, sizeof(vid));
1131     vid = virtio_lduw_p(vdev, &vid);
1132     if (s != sizeof(vid)) {
1133         return VIRTIO_NET_ERR;
1134     }
1135 
1136     if (vid >= MAX_VLAN)
1137         return VIRTIO_NET_ERR;
1138 
1139     if (cmd == VIRTIO_NET_CTRL_VLAN_ADD)
1140         n->vlans[vid >> 5] |= (1U << (vid & 0x1f));
1141     else if (cmd == VIRTIO_NET_CTRL_VLAN_DEL)
1142         n->vlans[vid >> 5] &= ~(1U << (vid & 0x1f));
1143     else
1144         return VIRTIO_NET_ERR;
1145 
1146     rxfilter_notify(nc);
1147 
1148     return VIRTIO_NET_OK;
1149 }
1150 
1151 static int virtio_net_handle_announce(VirtIONet *n, uint8_t cmd,
1152                                       struct iovec *iov, unsigned int iov_cnt)
1153 {
1154     trace_virtio_net_handle_announce(n->announce_timer.round);
1155     if (cmd == VIRTIO_NET_CTRL_ANNOUNCE_ACK &&
1156         n->status & VIRTIO_NET_S_ANNOUNCE) {
1157         n->status &= ~VIRTIO_NET_S_ANNOUNCE;
1158         if (n->announce_timer.round) {
1159             qemu_announce_timer_step(&n->announce_timer);
1160         }
1161         return VIRTIO_NET_OK;
1162     } else {
1163         return VIRTIO_NET_ERR;
1164     }
1165 }
1166 
1167 static void virtio_net_detach_epbf_rss(VirtIONet *n);
1168 
1169 static void virtio_net_disable_rss(VirtIONet *n)
1170 {
1171     if (n->rss_data.enabled) {
1172         trace_virtio_net_rss_disable();
1173     }
1174     n->rss_data.enabled = false;
1175 
1176     virtio_net_detach_epbf_rss(n);
1177 }
1178 
1179 static bool virtio_net_attach_ebpf_to_backend(NICState *nic, int prog_fd)
1180 {
1181     NetClientState *nc = qemu_get_peer(qemu_get_queue(nic), 0);
1182     if (nc == NULL || nc->info->set_steering_ebpf == NULL) {
1183         return false;
1184     }
1185 
1186     return nc->info->set_steering_ebpf(nc, prog_fd);
1187 }
1188 
1189 static void rss_data_to_rss_config(struct VirtioNetRssData *data,
1190                                    struct EBPFRSSConfig *config)
1191 {
1192     config->redirect = data->redirect;
1193     config->populate_hash = data->populate_hash;
1194     config->hash_types = data->hash_types;
1195     config->indirections_len = data->indirections_len;
1196     config->default_queue = data->default_queue;
1197 }
1198 
1199 static bool virtio_net_attach_epbf_rss(VirtIONet *n)
1200 {
1201     struct EBPFRSSConfig config = {};
1202 
1203     if (!ebpf_rss_is_loaded(&n->ebpf_rss)) {
1204         return false;
1205     }
1206 
1207     rss_data_to_rss_config(&n->rss_data, &config);
1208 
1209     if (!ebpf_rss_set_all(&n->ebpf_rss, &config,
1210                           n->rss_data.indirections_table, n->rss_data.key)) {
1211         return false;
1212     }
1213 
1214     if (!virtio_net_attach_ebpf_to_backend(n->nic, n->ebpf_rss.program_fd)) {
1215         return false;
1216     }
1217 
1218     return true;
1219 }
1220 
1221 static void virtio_net_detach_epbf_rss(VirtIONet *n)
1222 {
1223     virtio_net_attach_ebpf_to_backend(n->nic, -1);
1224 }
1225 
1226 static bool virtio_net_load_ebpf(VirtIONet *n)
1227 {
1228     if (!virtio_net_attach_ebpf_to_backend(n->nic, -1)) {
1229         /* backend does't support steering ebpf */
1230         return false;
1231     }
1232 
1233     return ebpf_rss_load(&n->ebpf_rss);
1234 }
1235 
1236 static void virtio_net_unload_ebpf(VirtIONet *n)
1237 {
1238     virtio_net_attach_ebpf_to_backend(n->nic, -1);
1239     ebpf_rss_unload(&n->ebpf_rss);
1240 }
1241 
1242 static uint16_t virtio_net_handle_rss(VirtIONet *n,
1243                                       struct iovec *iov,
1244                                       unsigned int iov_cnt,
1245                                       bool do_rss)
1246 {
1247     VirtIODevice *vdev = VIRTIO_DEVICE(n);
1248     struct virtio_net_rss_config cfg;
1249     size_t s, offset = 0, size_get;
1250     uint16_t queues, i;
1251     struct {
1252         uint16_t us;
1253         uint8_t b;
1254     } QEMU_PACKED temp;
1255     const char *err_msg = "";
1256     uint32_t err_value = 0;
1257 
1258     if (do_rss && !virtio_vdev_has_feature(vdev, VIRTIO_NET_F_RSS)) {
1259         err_msg = "RSS is not negotiated";
1260         goto error;
1261     }
1262     if (!do_rss && !virtio_vdev_has_feature(vdev, VIRTIO_NET_F_HASH_REPORT)) {
1263         err_msg = "Hash report is not negotiated";
1264         goto error;
1265     }
1266     size_get = offsetof(struct virtio_net_rss_config, indirection_table);
1267     s = iov_to_buf(iov, iov_cnt, offset, &cfg, size_get);
1268     if (s != size_get) {
1269         err_msg = "Short command buffer";
1270         err_value = (uint32_t)s;
1271         goto error;
1272     }
1273     n->rss_data.hash_types = virtio_ldl_p(vdev, &cfg.hash_types);
1274     n->rss_data.indirections_len =
1275         virtio_lduw_p(vdev, &cfg.indirection_table_mask);
1276     n->rss_data.indirections_len++;
1277     if (!do_rss) {
1278         n->rss_data.indirections_len = 1;
1279     }
1280     if (!is_power_of_2(n->rss_data.indirections_len)) {
1281         err_msg = "Invalid size of indirection table";
1282         err_value = n->rss_data.indirections_len;
1283         goto error;
1284     }
1285     if (n->rss_data.indirections_len > VIRTIO_NET_RSS_MAX_TABLE_LEN) {
1286         err_msg = "Too large indirection table";
1287         err_value = n->rss_data.indirections_len;
1288         goto error;
1289     }
1290     n->rss_data.default_queue = do_rss ?
1291         virtio_lduw_p(vdev, &cfg.unclassified_queue) : 0;
1292     if (n->rss_data.default_queue >= n->max_queues) {
1293         err_msg = "Invalid default queue";
1294         err_value = n->rss_data.default_queue;
1295         goto error;
1296     }
1297     offset += size_get;
1298     size_get = sizeof(uint16_t) * n->rss_data.indirections_len;
1299     g_free(n->rss_data.indirections_table);
1300     n->rss_data.indirections_table = g_malloc(size_get);
1301     if (!n->rss_data.indirections_table) {
1302         err_msg = "Can't allocate indirections table";
1303         err_value = n->rss_data.indirections_len;
1304         goto error;
1305     }
1306     s = iov_to_buf(iov, iov_cnt, offset,
1307                    n->rss_data.indirections_table, size_get);
1308     if (s != size_get) {
1309         err_msg = "Short indirection table buffer";
1310         err_value = (uint32_t)s;
1311         goto error;
1312     }
1313     for (i = 0; i < n->rss_data.indirections_len; ++i) {
1314         uint16_t val = n->rss_data.indirections_table[i];
1315         n->rss_data.indirections_table[i] = virtio_lduw_p(vdev, &val);
1316     }
1317     offset += size_get;
1318     size_get = sizeof(temp);
1319     s = iov_to_buf(iov, iov_cnt, offset, &temp, size_get);
1320     if (s != size_get) {
1321         err_msg = "Can't get queues";
1322         err_value = (uint32_t)s;
1323         goto error;
1324     }
1325     queues = do_rss ? virtio_lduw_p(vdev, &temp.us) : n->curr_queues;
1326     if (queues == 0 || queues > n->max_queues) {
1327         err_msg = "Invalid number of queues";
1328         err_value = queues;
1329         goto error;
1330     }
1331     if (temp.b > VIRTIO_NET_RSS_MAX_KEY_SIZE) {
1332         err_msg = "Invalid key size";
1333         err_value = temp.b;
1334         goto error;
1335     }
1336     if (!temp.b && n->rss_data.hash_types) {
1337         err_msg = "No key provided";
1338         err_value = 0;
1339         goto error;
1340     }
1341     if (!temp.b && !n->rss_data.hash_types) {
1342         virtio_net_disable_rss(n);
1343         return queues;
1344     }
1345     offset += size_get;
1346     size_get = temp.b;
1347     s = iov_to_buf(iov, iov_cnt, offset, n->rss_data.key, size_get);
1348     if (s != size_get) {
1349         err_msg = "Can get key buffer";
1350         err_value = (uint32_t)s;
1351         goto error;
1352     }
1353     n->rss_data.enabled = true;
1354 
1355     if (!n->rss_data.populate_hash) {
1356         if (!virtio_net_attach_epbf_rss(n)) {
1357             /* EBPF must be loaded for vhost */
1358             if (get_vhost_net(qemu_get_queue(n->nic)->peer)) {
1359                 warn_report("Can't load eBPF RSS for vhost");
1360                 goto error;
1361             }
1362             /* fallback to software RSS */
1363             warn_report("Can't load eBPF RSS - fallback to software RSS");
1364             n->rss_data.enabled_software_rss = true;
1365         }
1366     } else {
1367         /* use software RSS for hash populating */
1368         /* and detach eBPF if was loaded before */
1369         virtio_net_detach_epbf_rss(n);
1370         n->rss_data.enabled_software_rss = true;
1371     }
1372 
1373     trace_virtio_net_rss_enable(n->rss_data.hash_types,
1374                                 n->rss_data.indirections_len,
1375                                 temp.b);
1376     return queues;
1377 error:
1378     trace_virtio_net_rss_error(err_msg, err_value);
1379     virtio_net_disable_rss(n);
1380     return 0;
1381 }
1382 
1383 static int virtio_net_handle_mq(VirtIONet *n, uint8_t cmd,
1384                                 struct iovec *iov, unsigned int iov_cnt)
1385 {
1386     VirtIODevice *vdev = VIRTIO_DEVICE(n);
1387     uint16_t queues;
1388 
1389     virtio_net_disable_rss(n);
1390     if (cmd == VIRTIO_NET_CTRL_MQ_HASH_CONFIG) {
1391         queues = virtio_net_handle_rss(n, iov, iov_cnt, false);
1392         return queues ? VIRTIO_NET_OK : VIRTIO_NET_ERR;
1393     }
1394     if (cmd == VIRTIO_NET_CTRL_MQ_RSS_CONFIG) {
1395         queues = virtio_net_handle_rss(n, iov, iov_cnt, true);
1396     } else if (cmd == VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET) {
1397         struct virtio_net_ctrl_mq mq;
1398         size_t s;
1399         if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_MQ)) {
1400             return VIRTIO_NET_ERR;
1401         }
1402         s = iov_to_buf(iov, iov_cnt, 0, &mq, sizeof(mq));
1403         if (s != sizeof(mq)) {
1404             return VIRTIO_NET_ERR;
1405         }
1406         queues = virtio_lduw_p(vdev, &mq.virtqueue_pairs);
1407 
1408     } else {
1409         return VIRTIO_NET_ERR;
1410     }
1411 
1412     if (queues < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
1413         queues > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
1414         queues > n->max_queues ||
1415         !n->multiqueue) {
1416         return VIRTIO_NET_ERR;
1417     }
1418 
1419     n->curr_queues = queues;
1420     /* stop the backend before changing the number of queues to avoid handling a
1421      * disabled queue */
1422     virtio_net_set_status(vdev, vdev->status);
1423     virtio_net_set_queues(n);
1424 
1425     return VIRTIO_NET_OK;
1426 }
1427 
1428 static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
1429 {
1430     VirtIONet *n = VIRTIO_NET(vdev);
1431     struct virtio_net_ctrl_hdr ctrl;
1432     virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
1433     VirtQueueElement *elem;
1434     size_t s;
1435     struct iovec *iov, *iov2;
1436     unsigned int iov_cnt;
1437 
1438     for (;;) {
1439         elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
1440         if (!elem) {
1441             break;
1442         }
1443         if (iov_size(elem->in_sg, elem->in_num) < sizeof(status) ||
1444             iov_size(elem->out_sg, elem->out_num) < sizeof(ctrl)) {
1445             virtio_error(vdev, "virtio-net ctrl missing headers");
1446             virtqueue_detach_element(vq, elem, 0);
1447             g_free(elem);
1448             break;
1449         }
1450 
1451         iov_cnt = elem->out_num;
1452         iov2 = iov = g_memdup(elem->out_sg, sizeof(struct iovec) * elem->out_num);
1453         s = iov_to_buf(iov, iov_cnt, 0, &ctrl, sizeof(ctrl));
1454         iov_discard_front(&iov, &iov_cnt, sizeof(ctrl));
1455         if (s != sizeof(ctrl)) {
1456             status = VIRTIO_NET_ERR;
1457         } else if (ctrl.class == VIRTIO_NET_CTRL_RX) {
1458             status = virtio_net_handle_rx_mode(n, ctrl.cmd, iov, iov_cnt);
1459         } else if (ctrl.class == VIRTIO_NET_CTRL_MAC) {
1460             status = virtio_net_handle_mac(n, ctrl.cmd, iov, iov_cnt);
1461         } else if (ctrl.class == VIRTIO_NET_CTRL_VLAN) {
1462             status = virtio_net_handle_vlan_table(n, ctrl.cmd, iov, iov_cnt);
1463         } else if (ctrl.class == VIRTIO_NET_CTRL_ANNOUNCE) {
1464             status = virtio_net_handle_announce(n, ctrl.cmd, iov, iov_cnt);
1465         } else if (ctrl.class == VIRTIO_NET_CTRL_MQ) {
1466             status = virtio_net_handle_mq(n, ctrl.cmd, iov, iov_cnt);
1467         } else if (ctrl.class == VIRTIO_NET_CTRL_GUEST_OFFLOADS) {
1468             status = virtio_net_handle_offloads(n, ctrl.cmd, iov, iov_cnt);
1469         }
1470 
1471         s = iov_from_buf(elem->in_sg, elem->in_num, 0, &status, sizeof(status));
1472         assert(s == sizeof(status));
1473 
1474         virtqueue_push(vq, elem, sizeof(status));
1475         virtio_notify(vdev, vq);
1476         g_free(iov2);
1477         g_free(elem);
1478     }
1479 }
1480 
1481 /* RX */
1482 
1483 static void virtio_net_handle_rx(VirtIODevice *vdev, VirtQueue *vq)
1484 {
1485     VirtIONet *n = VIRTIO_NET(vdev);
1486     int queue_index = vq2q(virtio_get_queue_index(vq));
1487 
1488     qemu_flush_queued_packets(qemu_get_subqueue(n->nic, queue_index));
1489 }
1490 
1491 static bool virtio_net_can_receive(NetClientState *nc)
1492 {
1493     VirtIONet *n = qemu_get_nic_opaque(nc);
1494     VirtIODevice *vdev = VIRTIO_DEVICE(n);
1495     VirtIONetQueue *q = virtio_net_get_subqueue(nc);
1496 
1497     if (!vdev->vm_running) {
1498         return false;
1499     }
1500 
1501     if (nc->queue_index >= n->curr_queues) {
1502         return false;
1503     }
1504 
1505     if (!virtio_queue_ready(q->rx_vq) ||
1506         !(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
1507         return false;
1508     }
1509 
1510     return true;
1511 }
1512 
1513 static int virtio_net_has_buffers(VirtIONetQueue *q, int bufsize)
1514 {
1515     VirtIONet *n = q->n;
1516     if (virtio_queue_empty(q->rx_vq) ||
1517         (n->mergeable_rx_bufs &&
1518          !virtqueue_avail_bytes(q->rx_vq, bufsize, 0))) {
1519         virtio_queue_set_notification(q->rx_vq, 1);
1520 
1521         /* To avoid a race condition where the guest has made some buffers
1522          * available after the above check but before notification was
1523          * enabled, check for available buffers again.
1524          */
1525         if (virtio_queue_empty(q->rx_vq) ||
1526             (n->mergeable_rx_bufs &&
1527              !virtqueue_avail_bytes(q->rx_vq, bufsize, 0))) {
1528             return 0;
1529         }
1530     }
1531 
1532     virtio_queue_set_notification(q->rx_vq, 0);
1533     return 1;
1534 }
1535 
1536 static void virtio_net_hdr_swap(VirtIODevice *vdev, struct virtio_net_hdr *hdr)
1537 {
1538     virtio_tswap16s(vdev, &hdr->hdr_len);
1539     virtio_tswap16s(vdev, &hdr->gso_size);
1540     virtio_tswap16s(vdev, &hdr->csum_start);
1541     virtio_tswap16s(vdev, &hdr->csum_offset);
1542 }
1543 
1544 /* dhclient uses AF_PACKET but doesn't pass auxdata to the kernel so
1545  * it never finds out that the packets don't have valid checksums.  This
1546  * causes dhclient to get upset.  Fedora's carried a patch for ages to
1547  * fix this with Xen but it hasn't appeared in an upstream release of
1548  * dhclient yet.
1549  *
1550  * To avoid breaking existing guests, we catch udp packets and add
1551  * checksums.  This is terrible but it's better than hacking the guest
1552  * kernels.
1553  *
1554  * N.B. if we introduce a zero-copy API, this operation is no longer free so
1555  * we should provide a mechanism to disable it to avoid polluting the host
1556  * cache.
1557  */
1558 static void work_around_broken_dhclient(struct virtio_net_hdr *hdr,
1559                                         uint8_t *buf, size_t size)
1560 {
1561     if ((hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && /* missing csum */
1562         (size > 27 && size < 1500) && /* normal sized MTU */
1563         (buf[12] == 0x08 && buf[13] == 0x00) && /* ethertype == IPv4 */
1564         (buf[23] == 17) && /* ip.protocol == UDP */
1565         (buf[34] == 0 && buf[35] == 67)) { /* udp.srcport == bootps */
1566         net_checksum_calculate(buf, size, CSUM_UDP);
1567         hdr->flags &= ~VIRTIO_NET_HDR_F_NEEDS_CSUM;
1568     }
1569 }
1570 
1571 static void receive_header(VirtIONet *n, const struct iovec *iov, int iov_cnt,
1572                            const void *buf, size_t size)
1573 {
1574     if (n->has_vnet_hdr) {
1575         /* FIXME this cast is evil */
1576         void *wbuf = (void *)buf;
1577         work_around_broken_dhclient(wbuf, wbuf + n->host_hdr_len,
1578                                     size - n->host_hdr_len);
1579 
1580         if (n->needs_vnet_hdr_swap) {
1581             virtio_net_hdr_swap(VIRTIO_DEVICE(n), wbuf);
1582         }
1583         iov_from_buf(iov, iov_cnt, 0, buf, sizeof(struct virtio_net_hdr));
1584     } else {
1585         struct virtio_net_hdr hdr = {
1586             .flags = 0,
1587             .gso_type = VIRTIO_NET_HDR_GSO_NONE
1588         };
1589         iov_from_buf(iov, iov_cnt, 0, &hdr, sizeof hdr);
1590     }
1591 }
1592 
1593 static int receive_filter(VirtIONet *n, const uint8_t *buf, int size)
1594 {
1595     static const uint8_t bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
1596     static const uint8_t vlan[] = {0x81, 0x00};
1597     uint8_t *ptr = (uint8_t *)buf;
1598     int i;
1599 
1600     if (n->promisc)
1601         return 1;
1602 
1603     ptr += n->host_hdr_len;
1604 
1605     if (!memcmp(&ptr[12], vlan, sizeof(vlan))) {
1606         int vid = lduw_be_p(ptr + 14) & 0xfff;
1607         if (!(n->vlans[vid >> 5] & (1U << (vid & 0x1f))))
1608             return 0;
1609     }
1610 
1611     if (ptr[0] & 1) { // multicast
1612         if (!memcmp(ptr, bcast, sizeof(bcast))) {
1613             return !n->nobcast;
1614         } else if (n->nomulti) {
1615             return 0;
1616         } else if (n->allmulti || n->mac_table.multi_overflow) {
1617             return 1;
1618         }
1619 
1620         for (i = n->mac_table.first_multi; i < n->mac_table.in_use; i++) {
1621             if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN)) {
1622                 return 1;
1623             }
1624         }
1625     } else { // unicast
1626         if (n->nouni) {
1627             return 0;
1628         } else if (n->alluni || n->mac_table.uni_overflow) {
1629             return 1;
1630         } else if (!memcmp(ptr, n->mac, ETH_ALEN)) {
1631             return 1;
1632         }
1633 
1634         for (i = 0; i < n->mac_table.first_multi; i++) {
1635             if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN)) {
1636                 return 1;
1637             }
1638         }
1639     }
1640 
1641     return 0;
1642 }
1643 
1644 static uint8_t virtio_net_get_hash_type(bool isip4,
1645                                         bool isip6,
1646                                         bool isudp,
1647                                         bool istcp,
1648                                         uint32_t types)
1649 {
1650     if (isip4) {
1651         if (istcp && (types & VIRTIO_NET_RSS_HASH_TYPE_TCPv4)) {
1652             return NetPktRssIpV4Tcp;
1653         }
1654         if (isudp && (types & VIRTIO_NET_RSS_HASH_TYPE_UDPv4)) {
1655             return NetPktRssIpV4Udp;
1656         }
1657         if (types & VIRTIO_NET_RSS_HASH_TYPE_IPv4) {
1658             return NetPktRssIpV4;
1659         }
1660     } else if (isip6) {
1661         uint32_t mask = VIRTIO_NET_RSS_HASH_TYPE_TCP_EX |
1662                         VIRTIO_NET_RSS_HASH_TYPE_TCPv6;
1663 
1664         if (istcp && (types & mask)) {
1665             return (types & VIRTIO_NET_RSS_HASH_TYPE_TCP_EX) ?
1666                 NetPktRssIpV6TcpEx : NetPktRssIpV6Tcp;
1667         }
1668         mask = VIRTIO_NET_RSS_HASH_TYPE_UDP_EX | VIRTIO_NET_RSS_HASH_TYPE_UDPv6;
1669         if (isudp && (types & mask)) {
1670             return (types & VIRTIO_NET_RSS_HASH_TYPE_UDP_EX) ?
1671                 NetPktRssIpV6UdpEx : NetPktRssIpV6Udp;
1672         }
1673         mask = VIRTIO_NET_RSS_HASH_TYPE_IP_EX | VIRTIO_NET_RSS_HASH_TYPE_IPv6;
1674         if (types & mask) {
1675             return (types & VIRTIO_NET_RSS_HASH_TYPE_IP_EX) ?
1676                 NetPktRssIpV6Ex : NetPktRssIpV6;
1677         }
1678     }
1679     return 0xff;
1680 }
1681 
1682 static void virtio_set_packet_hash(const uint8_t *buf, uint8_t report,
1683                                    uint32_t hash)
1684 {
1685     struct virtio_net_hdr_v1_hash *hdr = (void *)buf;
1686     hdr->hash_value = hash;
1687     hdr->hash_report = report;
1688 }
1689 
1690 static int virtio_net_process_rss(NetClientState *nc, const uint8_t *buf,
1691                                   size_t size)
1692 {
1693     VirtIONet *n = qemu_get_nic_opaque(nc);
1694     unsigned int index = nc->queue_index, new_index = index;
1695     struct NetRxPkt *pkt = n->rx_pkt;
1696     uint8_t net_hash_type;
1697     uint32_t hash;
1698     bool isip4, isip6, isudp, istcp;
1699     static const uint8_t reports[NetPktRssIpV6UdpEx + 1] = {
1700         VIRTIO_NET_HASH_REPORT_IPv4,
1701         VIRTIO_NET_HASH_REPORT_TCPv4,
1702         VIRTIO_NET_HASH_REPORT_TCPv6,
1703         VIRTIO_NET_HASH_REPORT_IPv6,
1704         VIRTIO_NET_HASH_REPORT_IPv6_EX,
1705         VIRTIO_NET_HASH_REPORT_TCPv6_EX,
1706         VIRTIO_NET_HASH_REPORT_UDPv4,
1707         VIRTIO_NET_HASH_REPORT_UDPv6,
1708         VIRTIO_NET_HASH_REPORT_UDPv6_EX
1709     };
1710 
1711     net_rx_pkt_set_protocols(pkt, buf + n->host_hdr_len,
1712                              size - n->host_hdr_len);
1713     net_rx_pkt_get_protocols(pkt, &isip4, &isip6, &isudp, &istcp);
1714     if (isip4 && (net_rx_pkt_get_ip4_info(pkt)->fragment)) {
1715         istcp = isudp = false;
1716     }
1717     if (isip6 && (net_rx_pkt_get_ip6_info(pkt)->fragment)) {
1718         istcp = isudp = false;
1719     }
1720     net_hash_type = virtio_net_get_hash_type(isip4, isip6, isudp, istcp,
1721                                              n->rss_data.hash_types);
1722     if (net_hash_type > NetPktRssIpV6UdpEx) {
1723         if (n->rss_data.populate_hash) {
1724             virtio_set_packet_hash(buf, VIRTIO_NET_HASH_REPORT_NONE, 0);
1725         }
1726         return n->rss_data.redirect ? n->rss_data.default_queue : -1;
1727     }
1728 
1729     hash = net_rx_pkt_calc_rss_hash(pkt, net_hash_type, n->rss_data.key);
1730 
1731     if (n->rss_data.populate_hash) {
1732         virtio_set_packet_hash(buf, reports[net_hash_type], hash);
1733     }
1734 
1735     if (n->rss_data.redirect) {
1736         new_index = hash & (n->rss_data.indirections_len - 1);
1737         new_index = n->rss_data.indirections_table[new_index];
1738     }
1739 
1740     return (index == new_index) ? -1 : new_index;
1741 }
1742 
1743 static ssize_t virtio_net_receive_rcu(NetClientState *nc, const uint8_t *buf,
1744                                       size_t size, bool no_rss)
1745 {
1746     VirtIONet *n = qemu_get_nic_opaque(nc);
1747     VirtIONetQueue *q = virtio_net_get_subqueue(nc);
1748     VirtIODevice *vdev = VIRTIO_DEVICE(n);
1749     struct iovec mhdr_sg[VIRTQUEUE_MAX_SIZE];
1750     struct virtio_net_hdr_mrg_rxbuf mhdr;
1751     unsigned mhdr_cnt = 0;
1752     size_t offset, i, guest_offset;
1753 
1754     if (!virtio_net_can_receive(nc)) {
1755         return -1;
1756     }
1757 
1758     if (!no_rss && n->rss_data.enabled && n->rss_data.enabled_software_rss) {
1759         int index = virtio_net_process_rss(nc, buf, size);
1760         if (index >= 0) {
1761             NetClientState *nc2 = qemu_get_subqueue(n->nic, index);
1762             return virtio_net_receive_rcu(nc2, buf, size, true);
1763         }
1764     }
1765 
1766     /* hdr_len refers to the header we supply to the guest */
1767     if (!virtio_net_has_buffers(q, size + n->guest_hdr_len - n->host_hdr_len)) {
1768         return 0;
1769     }
1770 
1771     if (!receive_filter(n, buf, size))
1772         return size;
1773 
1774     offset = i = 0;
1775 
1776     while (offset < size) {
1777         VirtQueueElement *elem;
1778         int len, total;
1779         const struct iovec *sg;
1780 
1781         total = 0;
1782 
1783         elem = virtqueue_pop(q->rx_vq, sizeof(VirtQueueElement));
1784         if (!elem) {
1785             if (i) {
1786                 virtio_error(vdev, "virtio-net unexpected empty queue: "
1787                              "i %zd mergeable %d offset %zd, size %zd, "
1788                              "guest hdr len %zd, host hdr len %zd "
1789                              "guest features 0x%" PRIx64,
1790                              i, n->mergeable_rx_bufs, offset, size,
1791                              n->guest_hdr_len, n->host_hdr_len,
1792                              vdev->guest_features);
1793             }
1794             return -1;
1795         }
1796 
1797         if (elem->in_num < 1) {
1798             virtio_error(vdev,
1799                          "virtio-net receive queue contains no in buffers");
1800             virtqueue_detach_element(q->rx_vq, elem, 0);
1801             g_free(elem);
1802             return -1;
1803         }
1804 
1805         sg = elem->in_sg;
1806         if (i == 0) {
1807             assert(offset == 0);
1808             if (n->mergeable_rx_bufs) {
1809                 mhdr_cnt = iov_copy(mhdr_sg, ARRAY_SIZE(mhdr_sg),
1810                                     sg, elem->in_num,
1811                                     offsetof(typeof(mhdr), num_buffers),
1812                                     sizeof(mhdr.num_buffers));
1813             }
1814 
1815             receive_header(n, sg, elem->in_num, buf, size);
1816             if (n->rss_data.populate_hash) {
1817                 offset = sizeof(mhdr);
1818                 iov_from_buf(sg, elem->in_num, offset,
1819                              buf + offset, n->host_hdr_len - sizeof(mhdr));
1820             }
1821             offset = n->host_hdr_len;
1822             total += n->guest_hdr_len;
1823             guest_offset = n->guest_hdr_len;
1824         } else {
1825             guest_offset = 0;
1826         }
1827 
1828         /* copy in packet.  ugh */
1829         len = iov_from_buf(sg, elem->in_num, guest_offset,
1830                            buf + offset, size - offset);
1831         total += len;
1832         offset += len;
1833         /* If buffers can't be merged, at this point we
1834          * must have consumed the complete packet.
1835          * Otherwise, drop it. */
1836         if (!n->mergeable_rx_bufs && offset < size) {
1837             virtqueue_unpop(q->rx_vq, elem, total);
1838             g_free(elem);
1839             return size;
1840         }
1841 
1842         /* signal other side */
1843         virtqueue_fill(q->rx_vq, elem, total, i++);
1844         g_free(elem);
1845     }
1846 
1847     if (mhdr_cnt) {
1848         virtio_stw_p(vdev, &mhdr.num_buffers, i);
1849         iov_from_buf(mhdr_sg, mhdr_cnt,
1850                      0,
1851                      &mhdr.num_buffers, sizeof mhdr.num_buffers);
1852     }
1853 
1854     virtqueue_flush(q->rx_vq, i);
1855     virtio_notify(vdev, q->rx_vq);
1856 
1857     return size;
1858 }
1859 
1860 static ssize_t virtio_net_do_receive(NetClientState *nc, const uint8_t *buf,
1861                                   size_t size)
1862 {
1863     RCU_READ_LOCK_GUARD();
1864 
1865     return virtio_net_receive_rcu(nc, buf, size, false);
1866 }
1867 
1868 static void virtio_net_rsc_extract_unit4(VirtioNetRscChain *chain,
1869                                          const uint8_t *buf,
1870                                          VirtioNetRscUnit *unit)
1871 {
1872     uint16_t ip_hdrlen;
1873     struct ip_header *ip;
1874 
1875     ip = (struct ip_header *)(buf + chain->n->guest_hdr_len
1876                               + sizeof(struct eth_header));
1877     unit->ip = (void *)ip;
1878     ip_hdrlen = (ip->ip_ver_len & 0xF) << 2;
1879     unit->ip_plen = &ip->ip_len;
1880     unit->tcp = (struct tcp_header *)(((uint8_t *)unit->ip) + ip_hdrlen);
1881     unit->tcp_hdrlen = (htons(unit->tcp->th_offset_flags) & 0xF000) >> 10;
1882     unit->payload = htons(*unit->ip_plen) - ip_hdrlen - unit->tcp_hdrlen;
1883 }
1884 
1885 static void virtio_net_rsc_extract_unit6(VirtioNetRscChain *chain,
1886                                          const uint8_t *buf,
1887                                          VirtioNetRscUnit *unit)
1888 {
1889     struct ip6_header *ip6;
1890 
1891     ip6 = (struct ip6_header *)(buf + chain->n->guest_hdr_len
1892                                  + sizeof(struct eth_header));
1893     unit->ip = ip6;
1894     unit->ip_plen = &(ip6->ip6_ctlun.ip6_un1.ip6_un1_plen);
1895     unit->tcp = (struct tcp_header *)(((uint8_t *)unit->ip)
1896                                         + sizeof(struct ip6_header));
1897     unit->tcp_hdrlen = (htons(unit->tcp->th_offset_flags) & 0xF000) >> 10;
1898 
1899     /* There is a difference between payload lenght in ipv4 and v6,
1900        ip header is excluded in ipv6 */
1901     unit->payload = htons(*unit->ip_plen) - unit->tcp_hdrlen;
1902 }
1903 
1904 static size_t virtio_net_rsc_drain_seg(VirtioNetRscChain *chain,
1905                                        VirtioNetRscSeg *seg)
1906 {
1907     int ret;
1908     struct virtio_net_hdr_v1 *h;
1909 
1910     h = (struct virtio_net_hdr_v1 *)seg->buf;
1911     h->flags = 0;
1912     h->gso_type = VIRTIO_NET_HDR_GSO_NONE;
1913 
1914     if (seg->is_coalesced) {
1915         h->rsc.segments = seg->packets;
1916         h->rsc.dup_acks = seg->dup_ack;
1917         h->flags = VIRTIO_NET_HDR_F_RSC_INFO;
1918         if (chain->proto == ETH_P_IP) {
1919             h->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
1920         } else {
1921             h->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
1922         }
1923     }
1924 
1925     ret = virtio_net_do_receive(seg->nc, seg->buf, seg->size);
1926     QTAILQ_REMOVE(&chain->buffers, seg, next);
1927     g_free(seg->buf);
1928     g_free(seg);
1929 
1930     return ret;
1931 }
1932 
1933 static void virtio_net_rsc_purge(void *opq)
1934 {
1935     VirtioNetRscSeg *seg, *rn;
1936     VirtioNetRscChain *chain = (VirtioNetRscChain *)opq;
1937 
1938     QTAILQ_FOREACH_SAFE(seg, &chain->buffers, next, rn) {
1939         if (virtio_net_rsc_drain_seg(chain, seg) == 0) {
1940             chain->stat.purge_failed++;
1941             continue;
1942         }
1943     }
1944 
1945     chain->stat.timer++;
1946     if (!QTAILQ_EMPTY(&chain->buffers)) {
1947         timer_mod(chain->drain_timer,
1948               qemu_clock_get_ns(QEMU_CLOCK_HOST) + chain->n->rsc_timeout);
1949     }
1950 }
1951 
1952 static void virtio_net_rsc_cleanup(VirtIONet *n)
1953 {
1954     VirtioNetRscChain *chain, *rn_chain;
1955     VirtioNetRscSeg *seg, *rn_seg;
1956 
1957     QTAILQ_FOREACH_SAFE(chain, &n->rsc_chains, next, rn_chain) {
1958         QTAILQ_FOREACH_SAFE(seg, &chain->buffers, next, rn_seg) {
1959             QTAILQ_REMOVE(&chain->buffers, seg, next);
1960             g_free(seg->buf);
1961             g_free(seg);
1962         }
1963 
1964         timer_free(chain->drain_timer);
1965         QTAILQ_REMOVE(&n->rsc_chains, chain, next);
1966         g_free(chain);
1967     }
1968 }
1969 
1970 static void virtio_net_rsc_cache_buf(VirtioNetRscChain *chain,
1971                                      NetClientState *nc,
1972                                      const uint8_t *buf, size_t size)
1973 {
1974     uint16_t hdr_len;
1975     VirtioNetRscSeg *seg;
1976 
1977     hdr_len = chain->n->guest_hdr_len;
1978     seg = g_malloc(sizeof(VirtioNetRscSeg));
1979     seg->buf = g_malloc(hdr_len + sizeof(struct eth_header)
1980         + sizeof(struct ip6_header) + VIRTIO_NET_MAX_TCP_PAYLOAD);
1981     memcpy(seg->buf, buf, size);
1982     seg->size = size;
1983     seg->packets = 1;
1984     seg->dup_ack = 0;
1985     seg->is_coalesced = 0;
1986     seg->nc = nc;
1987 
1988     QTAILQ_INSERT_TAIL(&chain->buffers, seg, next);
1989     chain->stat.cache++;
1990 
1991     switch (chain->proto) {
1992     case ETH_P_IP:
1993         virtio_net_rsc_extract_unit4(chain, seg->buf, &seg->unit);
1994         break;
1995     case ETH_P_IPV6:
1996         virtio_net_rsc_extract_unit6(chain, seg->buf, &seg->unit);
1997         break;
1998     default:
1999         g_assert_not_reached();
2000     }
2001 }
2002 
2003 static int32_t virtio_net_rsc_handle_ack(VirtioNetRscChain *chain,
2004                                          VirtioNetRscSeg *seg,
2005                                          const uint8_t *buf,
2006                                          struct tcp_header *n_tcp,
2007                                          struct tcp_header *o_tcp)
2008 {
2009     uint32_t nack, oack;
2010     uint16_t nwin, owin;
2011 
2012     nack = htonl(n_tcp->th_ack);
2013     nwin = htons(n_tcp->th_win);
2014     oack = htonl(o_tcp->th_ack);
2015     owin = htons(o_tcp->th_win);
2016 
2017     if ((nack - oack) >= VIRTIO_NET_MAX_TCP_PAYLOAD) {
2018         chain->stat.ack_out_of_win++;
2019         return RSC_FINAL;
2020     } else if (nack == oack) {
2021         /* duplicated ack or window probe */
2022         if (nwin == owin) {
2023             /* duplicated ack, add dup ack count due to whql test up to 1 */
2024             chain->stat.dup_ack++;
2025             return RSC_FINAL;
2026         } else {
2027             /* Coalesce window update */
2028             o_tcp->th_win = n_tcp->th_win;
2029             chain->stat.win_update++;
2030             return RSC_COALESCE;
2031         }
2032     } else {
2033         /* pure ack, go to 'C', finalize*/
2034         chain->stat.pure_ack++;
2035         return RSC_FINAL;
2036     }
2037 }
2038 
2039 static int32_t virtio_net_rsc_coalesce_data(VirtioNetRscChain *chain,
2040                                             VirtioNetRscSeg *seg,
2041                                             const uint8_t *buf,
2042                                             VirtioNetRscUnit *n_unit)
2043 {
2044     void *data;
2045     uint16_t o_ip_len;
2046     uint32_t nseq, oseq;
2047     VirtioNetRscUnit *o_unit;
2048 
2049     o_unit = &seg->unit;
2050     o_ip_len = htons(*o_unit->ip_plen);
2051     nseq = htonl(n_unit->tcp->th_seq);
2052     oseq = htonl(o_unit->tcp->th_seq);
2053 
2054     /* out of order or retransmitted. */
2055     if ((nseq - oseq) > VIRTIO_NET_MAX_TCP_PAYLOAD) {
2056         chain->stat.data_out_of_win++;
2057         return RSC_FINAL;
2058     }
2059 
2060     data = ((uint8_t *)n_unit->tcp) + n_unit->tcp_hdrlen;
2061     if (nseq == oseq) {
2062         if ((o_unit->payload == 0) && n_unit->payload) {
2063             /* From no payload to payload, normal case, not a dup ack or etc */
2064             chain->stat.data_after_pure_ack++;
2065             goto coalesce;
2066         } else {
2067             return virtio_net_rsc_handle_ack(chain, seg, buf,
2068                                              n_unit->tcp, o_unit->tcp);
2069         }
2070     } else if ((nseq - oseq) != o_unit->payload) {
2071         /* Not a consistent packet, out of order */
2072         chain->stat.data_out_of_order++;
2073         return RSC_FINAL;
2074     } else {
2075 coalesce:
2076         if ((o_ip_len + n_unit->payload) > chain->max_payload) {
2077             chain->stat.over_size++;
2078             return RSC_FINAL;
2079         }
2080 
2081         /* Here comes the right data, the payload length in v4/v6 is different,
2082            so use the field value to update and record the new data len */
2083         o_unit->payload += n_unit->payload; /* update new data len */
2084 
2085         /* update field in ip header */
2086         *o_unit->ip_plen = htons(o_ip_len + n_unit->payload);
2087 
2088         /* Bring 'PUSH' big, the whql test guide says 'PUSH' can be coalesced
2089            for windows guest, while this may change the behavior for linux
2090            guest (only if it uses RSC feature). */
2091         o_unit->tcp->th_offset_flags = n_unit->tcp->th_offset_flags;
2092 
2093         o_unit->tcp->th_ack = n_unit->tcp->th_ack;
2094         o_unit->tcp->th_win = n_unit->tcp->th_win;
2095 
2096         memmove(seg->buf + seg->size, data, n_unit->payload);
2097         seg->size += n_unit->payload;
2098         seg->packets++;
2099         chain->stat.coalesced++;
2100         return RSC_COALESCE;
2101     }
2102 }
2103 
2104 static int32_t virtio_net_rsc_coalesce4(VirtioNetRscChain *chain,
2105                                         VirtioNetRscSeg *seg,
2106                                         const uint8_t *buf, size_t size,
2107                                         VirtioNetRscUnit *unit)
2108 {
2109     struct ip_header *ip1, *ip2;
2110 
2111     ip1 = (struct ip_header *)(unit->ip);
2112     ip2 = (struct ip_header *)(seg->unit.ip);
2113     if ((ip1->ip_src ^ ip2->ip_src) || (ip1->ip_dst ^ ip2->ip_dst)
2114         || (unit->tcp->th_sport ^ seg->unit.tcp->th_sport)
2115         || (unit->tcp->th_dport ^ seg->unit.tcp->th_dport)) {
2116         chain->stat.no_match++;
2117         return RSC_NO_MATCH;
2118     }
2119 
2120     return virtio_net_rsc_coalesce_data(chain, seg, buf, unit);
2121 }
2122 
2123 static int32_t virtio_net_rsc_coalesce6(VirtioNetRscChain *chain,
2124                                         VirtioNetRscSeg *seg,
2125                                         const uint8_t *buf, size_t size,
2126                                         VirtioNetRscUnit *unit)
2127 {
2128     struct ip6_header *ip1, *ip2;
2129 
2130     ip1 = (struct ip6_header *)(unit->ip);
2131     ip2 = (struct ip6_header *)(seg->unit.ip);
2132     if (memcmp(&ip1->ip6_src, &ip2->ip6_src, sizeof(struct in6_address))
2133         || memcmp(&ip1->ip6_dst, &ip2->ip6_dst, sizeof(struct in6_address))
2134         || (unit->tcp->th_sport ^ seg->unit.tcp->th_sport)
2135         || (unit->tcp->th_dport ^ seg->unit.tcp->th_dport)) {
2136             chain->stat.no_match++;
2137             return RSC_NO_MATCH;
2138     }
2139 
2140     return virtio_net_rsc_coalesce_data(chain, seg, buf, unit);
2141 }
2142 
2143 /* Packets with 'SYN' should bypass, other flag should be sent after drain
2144  * to prevent out of order */
2145 static int virtio_net_rsc_tcp_ctrl_check(VirtioNetRscChain *chain,
2146                                          struct tcp_header *tcp)
2147 {
2148     uint16_t tcp_hdr;
2149     uint16_t tcp_flag;
2150 
2151     tcp_flag = htons(tcp->th_offset_flags);
2152     tcp_hdr = (tcp_flag & VIRTIO_NET_TCP_HDR_LENGTH) >> 10;
2153     tcp_flag &= VIRTIO_NET_TCP_FLAG;
2154     if (tcp_flag & TH_SYN) {
2155         chain->stat.tcp_syn++;
2156         return RSC_BYPASS;
2157     }
2158 
2159     if (tcp_flag & (TH_FIN | TH_URG | TH_RST | TH_ECE | TH_CWR)) {
2160         chain->stat.tcp_ctrl_drain++;
2161         return RSC_FINAL;
2162     }
2163 
2164     if (tcp_hdr > sizeof(struct tcp_header)) {
2165         chain->stat.tcp_all_opt++;
2166         return RSC_FINAL;
2167     }
2168 
2169     return RSC_CANDIDATE;
2170 }
2171 
2172 static size_t virtio_net_rsc_do_coalesce(VirtioNetRscChain *chain,
2173                                          NetClientState *nc,
2174                                          const uint8_t *buf, size_t size,
2175                                          VirtioNetRscUnit *unit)
2176 {
2177     int ret;
2178     VirtioNetRscSeg *seg, *nseg;
2179 
2180     if (QTAILQ_EMPTY(&chain->buffers)) {
2181         chain->stat.empty_cache++;
2182         virtio_net_rsc_cache_buf(chain, nc, buf, size);
2183         timer_mod(chain->drain_timer,
2184               qemu_clock_get_ns(QEMU_CLOCK_HOST) + chain->n->rsc_timeout);
2185         return size;
2186     }
2187 
2188     QTAILQ_FOREACH_SAFE(seg, &chain->buffers, next, nseg) {
2189         if (chain->proto == ETH_P_IP) {
2190             ret = virtio_net_rsc_coalesce4(chain, seg, buf, size, unit);
2191         } else {
2192             ret = virtio_net_rsc_coalesce6(chain, seg, buf, size, unit);
2193         }
2194 
2195         if (ret == RSC_FINAL) {
2196             if (virtio_net_rsc_drain_seg(chain, seg) == 0) {
2197                 /* Send failed */
2198                 chain->stat.final_failed++;
2199                 return 0;
2200             }
2201 
2202             /* Send current packet */
2203             return virtio_net_do_receive(nc, buf, size);
2204         } else if (ret == RSC_NO_MATCH) {
2205             continue;
2206         } else {
2207             /* Coalesced, mark coalesced flag to tell calc cksum for ipv4 */
2208             seg->is_coalesced = 1;
2209             return size;
2210         }
2211     }
2212 
2213     chain->stat.no_match_cache++;
2214     virtio_net_rsc_cache_buf(chain, nc, buf, size);
2215     return size;
2216 }
2217 
2218 /* Drain a connection data, this is to avoid out of order segments */
2219 static size_t virtio_net_rsc_drain_flow(VirtioNetRscChain *chain,
2220                                         NetClientState *nc,
2221                                         const uint8_t *buf, size_t size,
2222                                         uint16_t ip_start, uint16_t ip_size,
2223                                         uint16_t tcp_port)
2224 {
2225     VirtioNetRscSeg *seg, *nseg;
2226     uint32_t ppair1, ppair2;
2227 
2228     ppair1 = *(uint32_t *)(buf + tcp_port);
2229     QTAILQ_FOREACH_SAFE(seg, &chain->buffers, next, nseg) {
2230         ppair2 = *(uint32_t *)(seg->buf + tcp_port);
2231         if (memcmp(buf + ip_start, seg->buf + ip_start, ip_size)
2232             || (ppair1 != ppair2)) {
2233             continue;
2234         }
2235         if (virtio_net_rsc_drain_seg(chain, seg) == 0) {
2236             chain->stat.drain_failed++;
2237         }
2238 
2239         break;
2240     }
2241 
2242     return virtio_net_do_receive(nc, buf, size);
2243 }
2244 
2245 static int32_t virtio_net_rsc_sanity_check4(VirtioNetRscChain *chain,
2246                                             struct ip_header *ip,
2247                                             const uint8_t *buf, size_t size)
2248 {
2249     uint16_t ip_len;
2250 
2251     /* Not an ipv4 packet */
2252     if (((ip->ip_ver_len & 0xF0) >> 4) != IP_HEADER_VERSION_4) {
2253         chain->stat.ip_option++;
2254         return RSC_BYPASS;
2255     }
2256 
2257     /* Don't handle packets with ip option */
2258     if ((ip->ip_ver_len & 0xF) != VIRTIO_NET_IP4_HEADER_LENGTH) {
2259         chain->stat.ip_option++;
2260         return RSC_BYPASS;
2261     }
2262 
2263     if (ip->ip_p != IPPROTO_TCP) {
2264         chain->stat.bypass_not_tcp++;
2265         return RSC_BYPASS;
2266     }
2267 
2268     /* Don't handle packets with ip fragment */
2269     if (!(htons(ip->ip_off) & IP_DF)) {
2270         chain->stat.ip_frag++;
2271         return RSC_BYPASS;
2272     }
2273 
2274     /* Don't handle packets with ecn flag */
2275     if (IPTOS_ECN(ip->ip_tos)) {
2276         chain->stat.ip_ecn++;
2277         return RSC_BYPASS;
2278     }
2279 
2280     ip_len = htons(ip->ip_len);
2281     if (ip_len < (sizeof(struct ip_header) + sizeof(struct tcp_header))
2282         || ip_len > (size - chain->n->guest_hdr_len -
2283                      sizeof(struct eth_header))) {
2284         chain->stat.ip_hacked++;
2285         return RSC_BYPASS;
2286     }
2287 
2288     return RSC_CANDIDATE;
2289 }
2290 
2291 static size_t virtio_net_rsc_receive4(VirtioNetRscChain *chain,
2292                                       NetClientState *nc,
2293                                       const uint8_t *buf, size_t size)
2294 {
2295     int32_t ret;
2296     uint16_t hdr_len;
2297     VirtioNetRscUnit unit;
2298 
2299     hdr_len = ((VirtIONet *)(chain->n))->guest_hdr_len;
2300 
2301     if (size < (hdr_len + sizeof(struct eth_header) + sizeof(struct ip_header)
2302         + sizeof(struct tcp_header))) {
2303         chain->stat.bypass_not_tcp++;
2304         return virtio_net_do_receive(nc, buf, size);
2305     }
2306 
2307     virtio_net_rsc_extract_unit4(chain, buf, &unit);
2308     if (virtio_net_rsc_sanity_check4(chain, unit.ip, buf, size)
2309         != RSC_CANDIDATE) {
2310         return virtio_net_do_receive(nc, buf, size);
2311     }
2312 
2313     ret = virtio_net_rsc_tcp_ctrl_check(chain, unit.tcp);
2314     if (ret == RSC_BYPASS) {
2315         return virtio_net_do_receive(nc, buf, size);
2316     } else if (ret == RSC_FINAL) {
2317         return virtio_net_rsc_drain_flow(chain, nc, buf, size,
2318                 ((hdr_len + sizeof(struct eth_header)) + 12),
2319                 VIRTIO_NET_IP4_ADDR_SIZE,
2320                 hdr_len + sizeof(struct eth_header) + sizeof(struct ip_header));
2321     }
2322 
2323     return virtio_net_rsc_do_coalesce(chain, nc, buf, size, &unit);
2324 }
2325 
2326 static int32_t virtio_net_rsc_sanity_check6(VirtioNetRscChain *chain,
2327                                             struct ip6_header *ip6,
2328                                             const uint8_t *buf, size_t size)
2329 {
2330     uint16_t ip_len;
2331 
2332     if (((ip6->ip6_ctlun.ip6_un1.ip6_un1_flow & 0xF0) >> 4)
2333         != IP_HEADER_VERSION_6) {
2334         return RSC_BYPASS;
2335     }
2336 
2337     /* Both option and protocol is checked in this */
2338     if (ip6->ip6_ctlun.ip6_un1.ip6_un1_nxt != IPPROTO_TCP) {
2339         chain->stat.bypass_not_tcp++;
2340         return RSC_BYPASS;
2341     }
2342 
2343     ip_len = htons(ip6->ip6_ctlun.ip6_un1.ip6_un1_plen);
2344     if (ip_len < sizeof(struct tcp_header) ||
2345         ip_len > (size - chain->n->guest_hdr_len - sizeof(struct eth_header)
2346                   - sizeof(struct ip6_header))) {
2347         chain->stat.ip_hacked++;
2348         return RSC_BYPASS;
2349     }
2350 
2351     /* Don't handle packets with ecn flag */
2352     if (IP6_ECN(ip6->ip6_ctlun.ip6_un3.ip6_un3_ecn)) {
2353         chain->stat.ip_ecn++;
2354         return RSC_BYPASS;
2355     }
2356 
2357     return RSC_CANDIDATE;
2358 }
2359 
2360 static size_t virtio_net_rsc_receive6(void *opq, NetClientState *nc,
2361                                       const uint8_t *buf, size_t size)
2362 {
2363     int32_t ret;
2364     uint16_t hdr_len;
2365     VirtioNetRscChain *chain;
2366     VirtioNetRscUnit unit;
2367 
2368     chain = (VirtioNetRscChain *)opq;
2369     hdr_len = ((VirtIONet *)(chain->n))->guest_hdr_len;
2370 
2371     if (size < (hdr_len + sizeof(struct eth_header) + sizeof(struct ip6_header)
2372         + sizeof(tcp_header))) {
2373         return virtio_net_do_receive(nc, buf, size);
2374     }
2375 
2376     virtio_net_rsc_extract_unit6(chain, buf, &unit);
2377     if (RSC_CANDIDATE != virtio_net_rsc_sanity_check6(chain,
2378                                                  unit.ip, buf, size)) {
2379         return virtio_net_do_receive(nc, buf, size);
2380     }
2381 
2382     ret = virtio_net_rsc_tcp_ctrl_check(chain, unit.tcp);
2383     if (ret == RSC_BYPASS) {
2384         return virtio_net_do_receive(nc, buf, size);
2385     } else if (ret == RSC_FINAL) {
2386         return virtio_net_rsc_drain_flow(chain, nc, buf, size,
2387                 ((hdr_len + sizeof(struct eth_header)) + 8),
2388                 VIRTIO_NET_IP6_ADDR_SIZE,
2389                 hdr_len + sizeof(struct eth_header)
2390                 + sizeof(struct ip6_header));
2391     }
2392 
2393     return virtio_net_rsc_do_coalesce(chain, nc, buf, size, &unit);
2394 }
2395 
2396 static VirtioNetRscChain *virtio_net_rsc_lookup_chain(VirtIONet *n,
2397                                                       NetClientState *nc,
2398                                                       uint16_t proto)
2399 {
2400     VirtioNetRscChain *chain;
2401 
2402     if ((proto != (uint16_t)ETH_P_IP) && (proto != (uint16_t)ETH_P_IPV6)) {
2403         return NULL;
2404     }
2405 
2406     QTAILQ_FOREACH(chain, &n->rsc_chains, next) {
2407         if (chain->proto == proto) {
2408             return chain;
2409         }
2410     }
2411 
2412     chain = g_malloc(sizeof(*chain));
2413     chain->n = n;
2414     chain->proto = proto;
2415     if (proto == (uint16_t)ETH_P_IP) {
2416         chain->max_payload = VIRTIO_NET_MAX_IP4_PAYLOAD;
2417         chain->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
2418     } else {
2419         chain->max_payload = VIRTIO_NET_MAX_IP6_PAYLOAD;
2420         chain->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
2421     }
2422     chain->drain_timer = timer_new_ns(QEMU_CLOCK_HOST,
2423                                       virtio_net_rsc_purge, chain);
2424     memset(&chain->stat, 0, sizeof(chain->stat));
2425 
2426     QTAILQ_INIT(&chain->buffers);
2427     QTAILQ_INSERT_TAIL(&n->rsc_chains, chain, next);
2428 
2429     return chain;
2430 }
2431 
2432 static ssize_t virtio_net_rsc_receive(NetClientState *nc,
2433                                       const uint8_t *buf,
2434                                       size_t size)
2435 {
2436     uint16_t proto;
2437     VirtioNetRscChain *chain;
2438     struct eth_header *eth;
2439     VirtIONet *n;
2440 
2441     n = qemu_get_nic_opaque(nc);
2442     if (size < (n->host_hdr_len + sizeof(struct eth_header))) {
2443         return virtio_net_do_receive(nc, buf, size);
2444     }
2445 
2446     eth = (struct eth_header *)(buf + n->guest_hdr_len);
2447     proto = htons(eth->h_proto);
2448 
2449     chain = virtio_net_rsc_lookup_chain(n, nc, proto);
2450     if (chain) {
2451         chain->stat.received++;
2452         if (proto == (uint16_t)ETH_P_IP && n->rsc4_enabled) {
2453             return virtio_net_rsc_receive4(chain, nc, buf, size);
2454         } else if (proto == (uint16_t)ETH_P_IPV6 && n->rsc6_enabled) {
2455             return virtio_net_rsc_receive6(chain, nc, buf, size);
2456         }
2457     }
2458     return virtio_net_do_receive(nc, buf, size);
2459 }
2460 
2461 static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf,
2462                                   size_t size)
2463 {
2464     VirtIONet *n = qemu_get_nic_opaque(nc);
2465     if ((n->rsc4_enabled || n->rsc6_enabled)) {
2466         return virtio_net_rsc_receive(nc, buf, size);
2467     } else {
2468         return virtio_net_do_receive(nc, buf, size);
2469     }
2470 }
2471 
2472 static int32_t virtio_net_flush_tx(VirtIONetQueue *q);
2473 
2474 static void virtio_net_tx_complete(NetClientState *nc, ssize_t len)
2475 {
2476     VirtIONet *n = qemu_get_nic_opaque(nc);
2477     VirtIONetQueue *q = virtio_net_get_subqueue(nc);
2478     VirtIODevice *vdev = VIRTIO_DEVICE(n);
2479 
2480     virtqueue_push(q->tx_vq, q->async_tx.elem, 0);
2481     virtio_notify(vdev, q->tx_vq);
2482 
2483     g_free(q->async_tx.elem);
2484     q->async_tx.elem = NULL;
2485 
2486     virtio_queue_set_notification(q->tx_vq, 1);
2487     virtio_net_flush_tx(q);
2488 }
2489 
2490 /* TX */
2491 static int32_t virtio_net_flush_tx(VirtIONetQueue *q)
2492 {
2493     VirtIONet *n = q->n;
2494     VirtIODevice *vdev = VIRTIO_DEVICE(n);
2495     VirtQueueElement *elem;
2496     int32_t num_packets = 0;
2497     int queue_index = vq2q(virtio_get_queue_index(q->tx_vq));
2498     if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
2499         return num_packets;
2500     }
2501 
2502     if (q->async_tx.elem) {
2503         virtio_queue_set_notification(q->tx_vq, 0);
2504         return num_packets;
2505     }
2506 
2507     for (;;) {
2508         ssize_t ret;
2509         unsigned int out_num;
2510         struct iovec sg[VIRTQUEUE_MAX_SIZE], sg2[VIRTQUEUE_MAX_SIZE + 1], *out_sg;
2511         struct virtio_net_hdr_mrg_rxbuf mhdr;
2512 
2513         elem = virtqueue_pop(q->tx_vq, sizeof(VirtQueueElement));
2514         if (!elem) {
2515             break;
2516         }
2517 
2518         out_num = elem->out_num;
2519         out_sg = elem->out_sg;
2520         if (out_num < 1) {
2521             virtio_error(vdev, "virtio-net header not in first element");
2522             virtqueue_detach_element(q->tx_vq, elem, 0);
2523             g_free(elem);
2524             return -EINVAL;
2525         }
2526 
2527         if (n->has_vnet_hdr) {
2528             if (iov_to_buf(out_sg, out_num, 0, &mhdr, n->guest_hdr_len) <
2529                 n->guest_hdr_len) {
2530                 virtio_error(vdev, "virtio-net header incorrect");
2531                 virtqueue_detach_element(q->tx_vq, elem, 0);
2532                 g_free(elem);
2533                 return -EINVAL;
2534             }
2535             if (n->needs_vnet_hdr_swap) {
2536                 virtio_net_hdr_swap(vdev, (void *) &mhdr);
2537                 sg2[0].iov_base = &mhdr;
2538                 sg2[0].iov_len = n->guest_hdr_len;
2539                 out_num = iov_copy(&sg2[1], ARRAY_SIZE(sg2) - 1,
2540                                    out_sg, out_num,
2541                                    n->guest_hdr_len, -1);
2542                 if (out_num == VIRTQUEUE_MAX_SIZE) {
2543                     goto drop;
2544                 }
2545                 out_num += 1;
2546                 out_sg = sg2;
2547             }
2548         }
2549         /*
2550          * If host wants to see the guest header as is, we can
2551          * pass it on unchanged. Otherwise, copy just the parts
2552          * that host is interested in.
2553          */
2554         assert(n->host_hdr_len <= n->guest_hdr_len);
2555         if (n->host_hdr_len != n->guest_hdr_len) {
2556             unsigned sg_num = iov_copy(sg, ARRAY_SIZE(sg),
2557                                        out_sg, out_num,
2558                                        0, n->host_hdr_len);
2559             sg_num += iov_copy(sg + sg_num, ARRAY_SIZE(sg) - sg_num,
2560                              out_sg, out_num,
2561                              n->guest_hdr_len, -1);
2562             out_num = sg_num;
2563             out_sg = sg;
2564         }
2565 
2566         ret = qemu_sendv_packet_async(qemu_get_subqueue(n->nic, queue_index),
2567                                       out_sg, out_num, virtio_net_tx_complete);
2568         if (ret == 0) {
2569             virtio_queue_set_notification(q->tx_vq, 0);
2570             q->async_tx.elem = elem;
2571             return -EBUSY;
2572         }
2573 
2574 drop:
2575         virtqueue_push(q->tx_vq, elem, 0);
2576         virtio_notify(vdev, q->tx_vq);
2577         g_free(elem);
2578 
2579         if (++num_packets >= n->tx_burst) {
2580             break;
2581         }
2582     }
2583     return num_packets;
2584 }
2585 
2586 static void virtio_net_handle_tx_timer(VirtIODevice *vdev, VirtQueue *vq)
2587 {
2588     VirtIONet *n = VIRTIO_NET(vdev);
2589     VirtIONetQueue *q = &n->vqs[vq2q(virtio_get_queue_index(vq))];
2590 
2591     if (unlikely((n->status & VIRTIO_NET_S_LINK_UP) == 0)) {
2592         virtio_net_drop_tx_queue_data(vdev, vq);
2593         return;
2594     }
2595 
2596     /* This happens when device was stopped but VCPU wasn't. */
2597     if (!vdev->vm_running) {
2598         q->tx_waiting = 1;
2599         return;
2600     }
2601 
2602     if (q->tx_waiting) {
2603         virtio_queue_set_notification(vq, 1);
2604         timer_del(q->tx_timer);
2605         q->tx_waiting = 0;
2606         if (virtio_net_flush_tx(q) == -EINVAL) {
2607             return;
2608         }
2609     } else {
2610         timer_mod(q->tx_timer,
2611                        qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + n->tx_timeout);
2612         q->tx_waiting = 1;
2613         virtio_queue_set_notification(vq, 0);
2614     }
2615 }
2616 
2617 static void virtio_net_handle_tx_bh(VirtIODevice *vdev, VirtQueue *vq)
2618 {
2619     VirtIONet *n = VIRTIO_NET(vdev);
2620     VirtIONetQueue *q = &n->vqs[vq2q(virtio_get_queue_index(vq))];
2621 
2622     if (unlikely((n->status & VIRTIO_NET_S_LINK_UP) == 0)) {
2623         virtio_net_drop_tx_queue_data(vdev, vq);
2624         return;
2625     }
2626 
2627     if (unlikely(q->tx_waiting)) {
2628         return;
2629     }
2630     q->tx_waiting = 1;
2631     /* This happens when device was stopped but VCPU wasn't. */
2632     if (!vdev->vm_running) {
2633         return;
2634     }
2635     virtio_queue_set_notification(vq, 0);
2636     qemu_bh_schedule(q->tx_bh);
2637 }
2638 
2639 static void virtio_net_tx_timer(void *opaque)
2640 {
2641     VirtIONetQueue *q = opaque;
2642     VirtIONet *n = q->n;
2643     VirtIODevice *vdev = VIRTIO_DEVICE(n);
2644     /* This happens when device was stopped but BH wasn't. */
2645     if (!vdev->vm_running) {
2646         /* Make sure tx waiting is set, so we'll run when restarted. */
2647         assert(q->tx_waiting);
2648         return;
2649     }
2650 
2651     q->tx_waiting = 0;
2652 
2653     /* Just in case the driver is not ready on more */
2654     if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
2655         return;
2656     }
2657 
2658     virtio_queue_set_notification(q->tx_vq, 1);
2659     virtio_net_flush_tx(q);
2660 }
2661 
2662 static void virtio_net_tx_bh(void *opaque)
2663 {
2664     VirtIONetQueue *q = opaque;
2665     VirtIONet *n = q->n;
2666     VirtIODevice *vdev = VIRTIO_DEVICE(n);
2667     int32_t ret;
2668 
2669     /* This happens when device was stopped but BH wasn't. */
2670     if (!vdev->vm_running) {
2671         /* Make sure tx waiting is set, so we'll run when restarted. */
2672         assert(q->tx_waiting);
2673         return;
2674     }
2675 
2676     q->tx_waiting = 0;
2677 
2678     /* Just in case the driver is not ready on more */
2679     if (unlikely(!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK))) {
2680         return;
2681     }
2682 
2683     ret = virtio_net_flush_tx(q);
2684     if (ret == -EBUSY || ret == -EINVAL) {
2685         return; /* Notification re-enable handled by tx_complete or device
2686                  * broken */
2687     }
2688 
2689     /* If we flush a full burst of packets, assume there are
2690      * more coming and immediately reschedule */
2691     if (ret >= n->tx_burst) {
2692         qemu_bh_schedule(q->tx_bh);
2693         q->tx_waiting = 1;
2694         return;
2695     }
2696 
2697     /* If less than a full burst, re-enable notification and flush
2698      * anything that may have come in while we weren't looking.  If
2699      * we find something, assume the guest is still active and reschedule */
2700     virtio_queue_set_notification(q->tx_vq, 1);
2701     ret = virtio_net_flush_tx(q);
2702     if (ret == -EINVAL) {
2703         return;
2704     } else if (ret > 0) {
2705         virtio_queue_set_notification(q->tx_vq, 0);
2706         qemu_bh_schedule(q->tx_bh);
2707         q->tx_waiting = 1;
2708     }
2709 }
2710 
2711 static void virtio_net_add_queue(VirtIONet *n, int index)
2712 {
2713     VirtIODevice *vdev = VIRTIO_DEVICE(n);
2714 
2715     n->vqs[index].rx_vq = virtio_add_queue(vdev, n->net_conf.rx_queue_size,
2716                                            virtio_net_handle_rx);
2717 
2718     if (n->net_conf.tx && !strcmp(n->net_conf.tx, "timer")) {
2719         n->vqs[index].tx_vq =
2720             virtio_add_queue(vdev, n->net_conf.tx_queue_size,
2721                              virtio_net_handle_tx_timer);
2722         n->vqs[index].tx_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
2723                                               virtio_net_tx_timer,
2724                                               &n->vqs[index]);
2725     } else {
2726         n->vqs[index].tx_vq =
2727             virtio_add_queue(vdev, n->net_conf.tx_queue_size,
2728                              virtio_net_handle_tx_bh);
2729         n->vqs[index].tx_bh = qemu_bh_new(virtio_net_tx_bh, &n->vqs[index]);
2730     }
2731 
2732     n->vqs[index].tx_waiting = 0;
2733     n->vqs[index].n = n;
2734 }
2735 
2736 static void virtio_net_del_queue(VirtIONet *n, int index)
2737 {
2738     VirtIODevice *vdev = VIRTIO_DEVICE(n);
2739     VirtIONetQueue *q = &n->vqs[index];
2740     NetClientState *nc = qemu_get_subqueue(n->nic, index);
2741 
2742     qemu_purge_queued_packets(nc);
2743 
2744     virtio_del_queue(vdev, index * 2);
2745     if (q->tx_timer) {
2746         timer_free(q->tx_timer);
2747         q->tx_timer = NULL;
2748     } else {
2749         qemu_bh_delete(q->tx_bh);
2750         q->tx_bh = NULL;
2751     }
2752     q->tx_waiting = 0;
2753     virtio_del_queue(vdev, index * 2 + 1);
2754 }
2755 
2756 static void virtio_net_change_num_queues(VirtIONet *n, int new_max_queues)
2757 {
2758     VirtIODevice *vdev = VIRTIO_DEVICE(n);
2759     int old_num_queues = virtio_get_num_queues(vdev);
2760     int new_num_queues = new_max_queues * 2 + 1;
2761     int i;
2762 
2763     assert(old_num_queues >= 3);
2764     assert(old_num_queues % 2 == 1);
2765 
2766     if (old_num_queues == new_num_queues) {
2767         return;
2768     }
2769 
2770     /*
2771      * We always need to remove and add ctrl vq if
2772      * old_num_queues != new_num_queues. Remove ctrl_vq first,
2773      * and then we only enter one of the following two loops.
2774      */
2775     virtio_del_queue(vdev, old_num_queues - 1);
2776 
2777     for (i = new_num_queues - 1; i < old_num_queues - 1; i += 2) {
2778         /* new_num_queues < old_num_queues */
2779         virtio_net_del_queue(n, i / 2);
2780     }
2781 
2782     for (i = old_num_queues - 1; i < new_num_queues - 1; i += 2) {
2783         /* new_num_queues > old_num_queues */
2784         virtio_net_add_queue(n, i / 2);
2785     }
2786 
2787     /* add ctrl_vq last */
2788     n->ctrl_vq = virtio_add_queue(vdev, 64, virtio_net_handle_ctrl);
2789 }
2790 
2791 static void virtio_net_set_multiqueue(VirtIONet *n, int multiqueue)
2792 {
2793     int max = multiqueue ? n->max_queues : 1;
2794 
2795     n->multiqueue = multiqueue;
2796     virtio_net_change_num_queues(n, max);
2797 
2798     virtio_net_set_queues(n);
2799 }
2800 
2801 static int virtio_net_post_load_device(void *opaque, int version_id)
2802 {
2803     VirtIONet *n = opaque;
2804     VirtIODevice *vdev = VIRTIO_DEVICE(n);
2805     int i, link_down;
2806 
2807     trace_virtio_net_post_load_device();
2808     virtio_net_set_mrg_rx_bufs(n, n->mergeable_rx_bufs,
2809                                virtio_vdev_has_feature(vdev,
2810                                                        VIRTIO_F_VERSION_1),
2811                                virtio_vdev_has_feature(vdev,
2812                                                        VIRTIO_NET_F_HASH_REPORT));
2813 
2814     /* MAC_TABLE_ENTRIES may be different from the saved image */
2815     if (n->mac_table.in_use > MAC_TABLE_ENTRIES) {
2816         n->mac_table.in_use = 0;
2817     }
2818 
2819     if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)) {
2820         n->curr_guest_offloads = virtio_net_supported_guest_offloads(n);
2821     }
2822 
2823     /*
2824      * curr_guest_offloads will be later overwritten by the
2825      * virtio_set_features_nocheck call done from the virtio_load.
2826      * Here we make sure it is preserved and restored accordingly
2827      * in the virtio_net_post_load_virtio callback.
2828      */
2829     n->saved_guest_offloads = n->curr_guest_offloads;
2830 
2831     virtio_net_set_queues(n);
2832 
2833     /* Find the first multicast entry in the saved MAC filter */
2834     for (i = 0; i < n->mac_table.in_use; i++) {
2835         if (n->mac_table.macs[i * ETH_ALEN] & 1) {
2836             break;
2837         }
2838     }
2839     n->mac_table.first_multi = i;
2840 
2841     /* nc.link_down can't be migrated, so infer link_down according
2842      * to link status bit in n->status */
2843     link_down = (n->status & VIRTIO_NET_S_LINK_UP) == 0;
2844     for (i = 0; i < n->max_queues; i++) {
2845         qemu_get_subqueue(n->nic, i)->link_down = link_down;
2846     }
2847 
2848     if (virtio_vdev_has_feature(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE) &&
2849         virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) {
2850         qemu_announce_timer_reset(&n->announce_timer, migrate_announce_params(),
2851                                   QEMU_CLOCK_VIRTUAL,
2852                                   virtio_net_announce_timer, n);
2853         if (n->announce_timer.round) {
2854             timer_mod(n->announce_timer.tm,
2855                       qemu_clock_get_ms(n->announce_timer.type));
2856         } else {
2857             qemu_announce_timer_del(&n->announce_timer, false);
2858         }
2859     }
2860 
2861     if (n->rss_data.enabled) {
2862         n->rss_data.enabled_software_rss = n->rss_data.populate_hash;
2863         if (!n->rss_data.populate_hash) {
2864             if (!virtio_net_attach_epbf_rss(n)) {
2865                 if (get_vhost_net(qemu_get_queue(n->nic)->peer)) {
2866                     warn_report("Can't post-load eBPF RSS for vhost");
2867                 } else {
2868                     warn_report("Can't post-load eBPF RSS - "
2869                                 "fallback to software RSS");
2870                     n->rss_data.enabled_software_rss = true;
2871                 }
2872             }
2873         }
2874 
2875         trace_virtio_net_rss_enable(n->rss_data.hash_types,
2876                                     n->rss_data.indirections_len,
2877                                     sizeof(n->rss_data.key));
2878     } else {
2879         trace_virtio_net_rss_disable();
2880     }
2881     return 0;
2882 }
2883 
2884 static int virtio_net_post_load_virtio(VirtIODevice *vdev)
2885 {
2886     VirtIONet *n = VIRTIO_NET(vdev);
2887     /*
2888      * The actual needed state is now in saved_guest_offloads,
2889      * see virtio_net_post_load_device for detail.
2890      * Restore it back and apply the desired offloads.
2891      */
2892     n->curr_guest_offloads = n->saved_guest_offloads;
2893     if (peer_has_vnet_hdr(n)) {
2894         virtio_net_apply_guest_offloads(n);
2895     }
2896 
2897     return 0;
2898 }
2899 
2900 /* tx_waiting field of a VirtIONetQueue */
2901 static const VMStateDescription vmstate_virtio_net_queue_tx_waiting = {
2902     .name = "virtio-net-queue-tx_waiting",
2903     .fields = (VMStateField[]) {
2904         VMSTATE_UINT32(tx_waiting, VirtIONetQueue),
2905         VMSTATE_END_OF_LIST()
2906    },
2907 };
2908 
2909 static bool max_queues_gt_1(void *opaque, int version_id)
2910 {
2911     return VIRTIO_NET(opaque)->max_queues > 1;
2912 }
2913 
2914 static bool has_ctrl_guest_offloads(void *opaque, int version_id)
2915 {
2916     return virtio_vdev_has_feature(VIRTIO_DEVICE(opaque),
2917                                    VIRTIO_NET_F_CTRL_GUEST_OFFLOADS);
2918 }
2919 
2920 static bool mac_table_fits(void *opaque, int version_id)
2921 {
2922     return VIRTIO_NET(opaque)->mac_table.in_use <= MAC_TABLE_ENTRIES;
2923 }
2924 
2925 static bool mac_table_doesnt_fit(void *opaque, int version_id)
2926 {
2927     return !mac_table_fits(opaque, version_id);
2928 }
2929 
2930 /* This temporary type is shared by all the WITH_TMP methods
2931  * although only some fields are used by each.
2932  */
2933 struct VirtIONetMigTmp {
2934     VirtIONet      *parent;
2935     VirtIONetQueue *vqs_1;
2936     uint16_t        curr_queues_1;
2937     uint8_t         has_ufo;
2938     uint32_t        has_vnet_hdr;
2939 };
2940 
2941 /* The 2nd and subsequent tx_waiting flags are loaded later than
2942  * the 1st entry in the queues and only if there's more than one
2943  * entry.  We use the tmp mechanism to calculate a temporary
2944  * pointer and count and also validate the count.
2945  */
2946 
2947 static int virtio_net_tx_waiting_pre_save(void *opaque)
2948 {
2949     struct VirtIONetMigTmp *tmp = opaque;
2950 
2951     tmp->vqs_1 = tmp->parent->vqs + 1;
2952     tmp->curr_queues_1 = tmp->parent->curr_queues - 1;
2953     if (tmp->parent->curr_queues == 0) {
2954         tmp->curr_queues_1 = 0;
2955     }
2956 
2957     return 0;
2958 }
2959 
2960 static int virtio_net_tx_waiting_pre_load(void *opaque)
2961 {
2962     struct VirtIONetMigTmp *tmp = opaque;
2963 
2964     /* Reuse the pointer setup from save */
2965     virtio_net_tx_waiting_pre_save(opaque);
2966 
2967     if (tmp->parent->curr_queues > tmp->parent->max_queues) {
2968         error_report("virtio-net: curr_queues %x > max_queues %x",
2969             tmp->parent->curr_queues, tmp->parent->max_queues);
2970 
2971         return -EINVAL;
2972     }
2973 
2974     return 0; /* all good */
2975 }
2976 
2977 static const VMStateDescription vmstate_virtio_net_tx_waiting = {
2978     .name      = "virtio-net-tx_waiting",
2979     .pre_load  = virtio_net_tx_waiting_pre_load,
2980     .pre_save  = virtio_net_tx_waiting_pre_save,
2981     .fields    = (VMStateField[]) {
2982         VMSTATE_STRUCT_VARRAY_POINTER_UINT16(vqs_1, struct VirtIONetMigTmp,
2983                                      curr_queues_1,
2984                                      vmstate_virtio_net_queue_tx_waiting,
2985                                      struct VirtIONetQueue),
2986         VMSTATE_END_OF_LIST()
2987     },
2988 };
2989 
2990 /* the 'has_ufo' flag is just tested; if the incoming stream has the
2991  * flag set we need to check that we have it
2992  */
2993 static int virtio_net_ufo_post_load(void *opaque, int version_id)
2994 {
2995     struct VirtIONetMigTmp *tmp = opaque;
2996 
2997     if (tmp->has_ufo && !peer_has_ufo(tmp->parent)) {
2998         error_report("virtio-net: saved image requires TUN_F_UFO support");
2999         return -EINVAL;
3000     }
3001 
3002     return 0;
3003 }
3004 
3005 static int virtio_net_ufo_pre_save(void *opaque)
3006 {
3007     struct VirtIONetMigTmp *tmp = opaque;
3008 
3009     tmp->has_ufo = tmp->parent->has_ufo;
3010 
3011     return 0;
3012 }
3013 
3014 static const VMStateDescription vmstate_virtio_net_has_ufo = {
3015     .name      = "virtio-net-ufo",
3016     .post_load = virtio_net_ufo_post_load,
3017     .pre_save  = virtio_net_ufo_pre_save,
3018     .fields    = (VMStateField[]) {
3019         VMSTATE_UINT8(has_ufo, struct VirtIONetMigTmp),
3020         VMSTATE_END_OF_LIST()
3021     },
3022 };
3023 
3024 /* the 'has_vnet_hdr' flag is just tested; if the incoming stream has the
3025  * flag set we need to check that we have it
3026  */
3027 static int virtio_net_vnet_post_load(void *opaque, int version_id)
3028 {
3029     struct VirtIONetMigTmp *tmp = opaque;
3030 
3031     if (tmp->has_vnet_hdr && !peer_has_vnet_hdr(tmp->parent)) {
3032         error_report("virtio-net: saved image requires vnet_hdr=on");
3033         return -EINVAL;
3034     }
3035 
3036     return 0;
3037 }
3038 
3039 static int virtio_net_vnet_pre_save(void *opaque)
3040 {
3041     struct VirtIONetMigTmp *tmp = opaque;
3042 
3043     tmp->has_vnet_hdr = tmp->parent->has_vnet_hdr;
3044 
3045     return 0;
3046 }
3047 
3048 static const VMStateDescription vmstate_virtio_net_has_vnet = {
3049     .name      = "virtio-net-vnet",
3050     .post_load = virtio_net_vnet_post_load,
3051     .pre_save  = virtio_net_vnet_pre_save,
3052     .fields    = (VMStateField[]) {
3053         VMSTATE_UINT32(has_vnet_hdr, struct VirtIONetMigTmp),
3054         VMSTATE_END_OF_LIST()
3055     },
3056 };
3057 
3058 static bool virtio_net_rss_needed(void *opaque)
3059 {
3060     return VIRTIO_NET(opaque)->rss_data.enabled;
3061 }
3062 
3063 static const VMStateDescription vmstate_virtio_net_rss = {
3064     .name      = "virtio-net-device/rss",
3065     .version_id = 1,
3066     .minimum_version_id = 1,
3067     .needed = virtio_net_rss_needed,
3068     .fields = (VMStateField[]) {
3069         VMSTATE_BOOL(rss_data.enabled, VirtIONet),
3070         VMSTATE_BOOL(rss_data.redirect, VirtIONet),
3071         VMSTATE_BOOL(rss_data.populate_hash, VirtIONet),
3072         VMSTATE_UINT32(rss_data.hash_types, VirtIONet),
3073         VMSTATE_UINT16(rss_data.indirections_len, VirtIONet),
3074         VMSTATE_UINT16(rss_data.default_queue, VirtIONet),
3075         VMSTATE_UINT8_ARRAY(rss_data.key, VirtIONet,
3076                             VIRTIO_NET_RSS_MAX_KEY_SIZE),
3077         VMSTATE_VARRAY_UINT16_ALLOC(rss_data.indirections_table, VirtIONet,
3078                                     rss_data.indirections_len, 0,
3079                                     vmstate_info_uint16, uint16_t),
3080         VMSTATE_END_OF_LIST()
3081     },
3082 };
3083 
3084 static const VMStateDescription vmstate_virtio_net_device = {
3085     .name = "virtio-net-device",
3086     .version_id = VIRTIO_NET_VM_VERSION,
3087     .minimum_version_id = VIRTIO_NET_VM_VERSION,
3088     .post_load = virtio_net_post_load_device,
3089     .fields = (VMStateField[]) {
3090         VMSTATE_UINT8_ARRAY(mac, VirtIONet, ETH_ALEN),
3091         VMSTATE_STRUCT_POINTER(vqs, VirtIONet,
3092                                vmstate_virtio_net_queue_tx_waiting,
3093                                VirtIONetQueue),
3094         VMSTATE_UINT32(mergeable_rx_bufs, VirtIONet),
3095         VMSTATE_UINT16(status, VirtIONet),
3096         VMSTATE_UINT8(promisc, VirtIONet),
3097         VMSTATE_UINT8(allmulti, VirtIONet),
3098         VMSTATE_UINT32(mac_table.in_use, VirtIONet),
3099 
3100         /* Guarded pair: If it fits we load it, else we throw it away
3101          * - can happen if source has a larger MAC table.; post-load
3102          *  sets flags in this case.
3103          */
3104         VMSTATE_VBUFFER_MULTIPLY(mac_table.macs, VirtIONet,
3105                                 0, mac_table_fits, mac_table.in_use,
3106                                  ETH_ALEN),
3107         VMSTATE_UNUSED_VARRAY_UINT32(VirtIONet, mac_table_doesnt_fit, 0,
3108                                      mac_table.in_use, ETH_ALEN),
3109 
3110         /* Note: This is an array of uint32's that's always been saved as a
3111          * buffer; hold onto your endiannesses; it's actually used as a bitmap
3112          * but based on the uint.
3113          */
3114         VMSTATE_BUFFER_POINTER_UNSAFE(vlans, VirtIONet, 0, MAX_VLAN >> 3),
3115         VMSTATE_WITH_TMP(VirtIONet, struct VirtIONetMigTmp,
3116                          vmstate_virtio_net_has_vnet),
3117         VMSTATE_UINT8(mac_table.multi_overflow, VirtIONet),
3118         VMSTATE_UINT8(mac_table.uni_overflow, VirtIONet),
3119         VMSTATE_UINT8(alluni, VirtIONet),
3120         VMSTATE_UINT8(nomulti, VirtIONet),
3121         VMSTATE_UINT8(nouni, VirtIONet),
3122         VMSTATE_UINT8(nobcast, VirtIONet),
3123         VMSTATE_WITH_TMP(VirtIONet, struct VirtIONetMigTmp,
3124                          vmstate_virtio_net_has_ufo),
3125         VMSTATE_SINGLE_TEST(max_queues, VirtIONet, max_queues_gt_1, 0,
3126                             vmstate_info_uint16_equal, uint16_t),
3127         VMSTATE_UINT16_TEST(curr_queues, VirtIONet, max_queues_gt_1),
3128         VMSTATE_WITH_TMP(VirtIONet, struct VirtIONetMigTmp,
3129                          vmstate_virtio_net_tx_waiting),
3130         VMSTATE_UINT64_TEST(curr_guest_offloads, VirtIONet,
3131                             has_ctrl_guest_offloads),
3132         VMSTATE_END_OF_LIST()
3133    },
3134     .subsections = (const VMStateDescription * []) {
3135         &vmstate_virtio_net_rss,
3136         NULL
3137     }
3138 };
3139 
3140 static NetClientInfo net_virtio_info = {
3141     .type = NET_CLIENT_DRIVER_NIC,
3142     .size = sizeof(NICState),
3143     .can_receive = virtio_net_can_receive,
3144     .receive = virtio_net_receive,
3145     .link_status_changed = virtio_net_set_link_status,
3146     .query_rx_filter = virtio_net_query_rxfilter,
3147     .announce = virtio_net_announce,
3148 };
3149 
3150 static bool virtio_net_guest_notifier_pending(VirtIODevice *vdev, int idx)
3151 {
3152     VirtIONet *n = VIRTIO_NET(vdev);
3153     NetClientState *nc = qemu_get_subqueue(n->nic, vq2q(idx));
3154     assert(n->vhost_started);
3155     return vhost_net_virtqueue_pending(get_vhost_net(nc->peer), idx);
3156 }
3157 
3158 static void virtio_net_guest_notifier_mask(VirtIODevice *vdev, int idx,
3159                                            bool mask)
3160 {
3161     VirtIONet *n = VIRTIO_NET(vdev);
3162     NetClientState *nc = qemu_get_subqueue(n->nic, vq2q(idx));
3163     assert(n->vhost_started);
3164     vhost_net_virtqueue_mask(get_vhost_net(nc->peer),
3165                              vdev, idx, mask);
3166 }
3167 
3168 static void virtio_net_set_config_size(VirtIONet *n, uint64_t host_features)
3169 {
3170     virtio_add_feature(&host_features, VIRTIO_NET_F_MAC);
3171 
3172     n->config_size = virtio_feature_get_config_size(feature_sizes,
3173                                                     host_features);
3174 }
3175 
3176 void virtio_net_set_netclient_name(VirtIONet *n, const char *name,
3177                                    const char *type)
3178 {
3179     /*
3180      * The name can be NULL, the netclient name will be type.x.
3181      */
3182     assert(type != NULL);
3183 
3184     g_free(n->netclient_name);
3185     g_free(n->netclient_type);
3186     n->netclient_name = g_strdup(name);
3187     n->netclient_type = g_strdup(type);
3188 }
3189 
3190 static bool failover_unplug_primary(VirtIONet *n, DeviceState *dev)
3191 {
3192     HotplugHandler *hotplug_ctrl;
3193     PCIDevice *pci_dev;
3194     Error *err = NULL;
3195 
3196     hotplug_ctrl = qdev_get_hotplug_handler(dev);
3197     if (hotplug_ctrl) {
3198         pci_dev = PCI_DEVICE(dev);
3199         pci_dev->partially_hotplugged = true;
3200         hotplug_handler_unplug_request(hotplug_ctrl, dev, &err);
3201         if (err) {
3202             error_report_err(err);
3203             return false;
3204         }
3205     } else {
3206         return false;
3207     }
3208     return true;
3209 }
3210 
3211 static bool failover_replug_primary(VirtIONet *n, DeviceState *dev,
3212                                     Error **errp)
3213 {
3214     Error *err = NULL;
3215     HotplugHandler *hotplug_ctrl;
3216     PCIDevice *pdev = PCI_DEVICE(dev);
3217     BusState *primary_bus;
3218 
3219     if (!pdev->partially_hotplugged) {
3220         return true;
3221     }
3222     primary_bus = dev->parent_bus;
3223     if (!primary_bus) {
3224         error_setg(errp, "virtio_net: couldn't find primary bus");
3225         return false;
3226     }
3227     qdev_set_parent_bus(dev, primary_bus, &error_abort);
3228     qatomic_set(&n->failover_primary_hidden, false);
3229     hotplug_ctrl = qdev_get_hotplug_handler(dev);
3230     if (hotplug_ctrl) {
3231         hotplug_handler_pre_plug(hotplug_ctrl, dev, &err);
3232         if (err) {
3233             goto out;
3234         }
3235         hotplug_handler_plug(hotplug_ctrl, dev, &err);
3236     }
3237 
3238 out:
3239     error_propagate(errp, err);
3240     return !err;
3241 }
3242 
3243 static void virtio_net_handle_migration_primary(VirtIONet *n, MigrationState *s)
3244 {
3245     bool should_be_hidden;
3246     Error *err = NULL;
3247     DeviceState *dev = failover_find_primary_device(n);
3248 
3249     if (!dev) {
3250         return;
3251     }
3252 
3253     should_be_hidden = qatomic_read(&n->failover_primary_hidden);
3254 
3255     if (migration_in_setup(s) && !should_be_hidden) {
3256         if (failover_unplug_primary(n, dev)) {
3257             vmstate_unregister(VMSTATE_IF(dev), qdev_get_vmsd(dev), dev);
3258             qapi_event_send_unplug_primary(dev->id);
3259             qatomic_set(&n->failover_primary_hidden, true);
3260         } else {
3261             warn_report("couldn't unplug primary device");
3262         }
3263     } else if (migration_has_failed(s)) {
3264         /* We already unplugged the device let's plug it back */
3265         if (!failover_replug_primary(n, dev, &err)) {
3266             if (err) {
3267                 error_report_err(err);
3268             }
3269         }
3270     }
3271 }
3272 
3273 static void virtio_net_migration_state_notifier(Notifier *notifier, void *data)
3274 {
3275     MigrationState *s = data;
3276     VirtIONet *n = container_of(notifier, VirtIONet, migration_state);
3277     virtio_net_handle_migration_primary(n, s);
3278 }
3279 
3280 static bool failover_hide_primary_device(DeviceListener *listener,
3281                                          QemuOpts *device_opts)
3282 {
3283     VirtIONet *n = container_of(listener, VirtIONet, primary_listener);
3284     const char *standby_id;
3285 
3286     if (!device_opts) {
3287         return false;
3288     }
3289     standby_id = qemu_opt_get(device_opts, "failover_pair_id");
3290     if (g_strcmp0(standby_id, n->netclient_name) != 0) {
3291         return false;
3292     }
3293 
3294     /* failover_primary_hidden is set during feature negotiation */
3295     return qatomic_read(&n->failover_primary_hidden);
3296 }
3297 
3298 static void virtio_net_device_realize(DeviceState *dev, Error **errp)
3299 {
3300     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
3301     VirtIONet *n = VIRTIO_NET(dev);
3302     NetClientState *nc;
3303     int i;
3304 
3305     if (n->net_conf.mtu) {
3306         n->host_features |= (1ULL << VIRTIO_NET_F_MTU);
3307     }
3308 
3309     if (n->net_conf.duplex_str) {
3310         if (strncmp(n->net_conf.duplex_str, "half", 5) == 0) {
3311             n->net_conf.duplex = DUPLEX_HALF;
3312         } else if (strncmp(n->net_conf.duplex_str, "full", 5) == 0) {
3313             n->net_conf.duplex = DUPLEX_FULL;
3314         } else {
3315             error_setg(errp, "'duplex' must be 'half' or 'full'");
3316             return;
3317         }
3318         n->host_features |= (1ULL << VIRTIO_NET_F_SPEED_DUPLEX);
3319     } else {
3320         n->net_conf.duplex = DUPLEX_UNKNOWN;
3321     }
3322 
3323     if (n->net_conf.speed < SPEED_UNKNOWN) {
3324         error_setg(errp, "'speed' must be between 0 and INT_MAX");
3325         return;
3326     }
3327     if (n->net_conf.speed >= 0) {
3328         n->host_features |= (1ULL << VIRTIO_NET_F_SPEED_DUPLEX);
3329     }
3330 
3331     if (n->failover) {
3332         n->primary_listener.hide_device = failover_hide_primary_device;
3333         qatomic_set(&n->failover_primary_hidden, true);
3334         device_listener_register(&n->primary_listener);
3335         n->migration_state.notify = virtio_net_migration_state_notifier;
3336         add_migration_state_change_notifier(&n->migration_state);
3337         n->host_features |= (1ULL << VIRTIO_NET_F_STANDBY);
3338     }
3339 
3340     virtio_net_set_config_size(n, n->host_features);
3341     virtio_init(vdev, "virtio-net", VIRTIO_ID_NET, n->config_size);
3342 
3343     /*
3344      * We set a lower limit on RX queue size to what it always was.
3345      * Guests that want a smaller ring can always resize it without
3346      * help from us (using virtio 1 and up).
3347      */
3348     if (n->net_conf.rx_queue_size < VIRTIO_NET_RX_QUEUE_MIN_SIZE ||
3349         n->net_conf.rx_queue_size > VIRTQUEUE_MAX_SIZE ||
3350         !is_power_of_2(n->net_conf.rx_queue_size)) {
3351         error_setg(errp, "Invalid rx_queue_size (= %" PRIu16 "), "
3352                    "must be a power of 2 between %d and %d.",
3353                    n->net_conf.rx_queue_size, VIRTIO_NET_RX_QUEUE_MIN_SIZE,
3354                    VIRTQUEUE_MAX_SIZE);
3355         virtio_cleanup(vdev);
3356         return;
3357     }
3358 
3359     if (n->net_conf.tx_queue_size < VIRTIO_NET_TX_QUEUE_MIN_SIZE ||
3360         n->net_conf.tx_queue_size > VIRTQUEUE_MAX_SIZE ||
3361         !is_power_of_2(n->net_conf.tx_queue_size)) {
3362         error_setg(errp, "Invalid tx_queue_size (= %" PRIu16 "), "
3363                    "must be a power of 2 between %d and %d",
3364                    n->net_conf.tx_queue_size, VIRTIO_NET_TX_QUEUE_MIN_SIZE,
3365                    VIRTQUEUE_MAX_SIZE);
3366         virtio_cleanup(vdev);
3367         return;
3368     }
3369 
3370     n->max_queues = MAX(n->nic_conf.peers.queues, 1);
3371     if (n->max_queues * 2 + 1 > VIRTIO_QUEUE_MAX) {
3372         error_setg(errp, "Invalid number of queues (= %" PRIu32 "), "
3373                    "must be a positive integer less than %d.",
3374                    n->max_queues, (VIRTIO_QUEUE_MAX - 1) / 2);
3375         virtio_cleanup(vdev);
3376         return;
3377     }
3378     n->vqs = g_malloc0(sizeof(VirtIONetQueue) * n->max_queues);
3379     n->curr_queues = 1;
3380     n->tx_timeout = n->net_conf.txtimer;
3381 
3382     if (n->net_conf.tx && strcmp(n->net_conf.tx, "timer")
3383                        && strcmp(n->net_conf.tx, "bh")) {
3384         warn_report("virtio-net: "
3385                     "Unknown option tx=%s, valid options: \"timer\" \"bh\"",
3386                     n->net_conf.tx);
3387         error_printf("Defaulting to \"bh\"");
3388     }
3389 
3390     n->net_conf.tx_queue_size = MIN(virtio_net_max_tx_queue_size(n),
3391                                     n->net_conf.tx_queue_size);
3392 
3393     for (i = 0; i < n->max_queues; i++) {
3394         virtio_net_add_queue(n, i);
3395     }
3396 
3397     n->ctrl_vq = virtio_add_queue(vdev, 64, virtio_net_handle_ctrl);
3398     qemu_macaddr_default_if_unset(&n->nic_conf.macaddr);
3399     memcpy(&n->mac[0], &n->nic_conf.macaddr, sizeof(n->mac));
3400     n->status = VIRTIO_NET_S_LINK_UP;
3401     qemu_announce_timer_reset(&n->announce_timer, migrate_announce_params(),
3402                               QEMU_CLOCK_VIRTUAL,
3403                               virtio_net_announce_timer, n);
3404     n->announce_timer.round = 0;
3405 
3406     if (n->netclient_type) {
3407         /*
3408          * Happen when virtio_net_set_netclient_name has been called.
3409          */
3410         n->nic = qemu_new_nic(&net_virtio_info, &n->nic_conf,
3411                               n->netclient_type, n->netclient_name, n);
3412     } else {
3413         n->nic = qemu_new_nic(&net_virtio_info, &n->nic_conf,
3414                               object_get_typename(OBJECT(dev)), dev->id, n);
3415     }
3416 
3417     for (i = 0; i < n->max_queues; i++) {
3418         n->nic->ncs[i].do_not_pad = true;
3419     }
3420 
3421     peer_test_vnet_hdr(n);
3422     if (peer_has_vnet_hdr(n)) {
3423         for (i = 0; i < n->max_queues; i++) {
3424             qemu_using_vnet_hdr(qemu_get_subqueue(n->nic, i)->peer, true);
3425         }
3426         n->host_hdr_len = sizeof(struct virtio_net_hdr);
3427     } else {
3428         n->host_hdr_len = 0;
3429     }
3430 
3431     qemu_format_nic_info_str(qemu_get_queue(n->nic), n->nic_conf.macaddr.a);
3432 
3433     n->vqs[0].tx_waiting = 0;
3434     n->tx_burst = n->net_conf.txburst;
3435     virtio_net_set_mrg_rx_bufs(n, 0, 0, 0);
3436     n->promisc = 1; /* for compatibility */
3437 
3438     n->mac_table.macs = g_malloc0(MAC_TABLE_ENTRIES * ETH_ALEN);
3439 
3440     n->vlans = g_malloc0(MAX_VLAN >> 3);
3441 
3442     nc = qemu_get_queue(n->nic);
3443     nc->rxfilter_notify_enabled = 1;
3444 
3445    if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_VDPA) {
3446         struct virtio_net_config netcfg = {};
3447         memcpy(&netcfg.mac, &n->nic_conf.macaddr, ETH_ALEN);
3448         vhost_net_set_config(get_vhost_net(nc->peer),
3449             (uint8_t *)&netcfg, 0, ETH_ALEN, VHOST_SET_CONFIG_TYPE_MASTER);
3450     }
3451     QTAILQ_INIT(&n->rsc_chains);
3452     n->qdev = dev;
3453 
3454     net_rx_pkt_init(&n->rx_pkt, false);
3455 
3456     if (virtio_has_feature(n->host_features, VIRTIO_NET_F_RSS)) {
3457         virtio_net_load_ebpf(n);
3458     }
3459 }
3460 
3461 static void virtio_net_device_unrealize(DeviceState *dev)
3462 {
3463     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
3464     VirtIONet *n = VIRTIO_NET(dev);
3465     int i, max_queues;
3466 
3467     if (virtio_has_feature(n->host_features, VIRTIO_NET_F_RSS)) {
3468         virtio_net_unload_ebpf(n);
3469     }
3470 
3471     /* This will stop vhost backend if appropriate. */
3472     virtio_net_set_status(vdev, 0);
3473 
3474     g_free(n->netclient_name);
3475     n->netclient_name = NULL;
3476     g_free(n->netclient_type);
3477     n->netclient_type = NULL;
3478 
3479     g_free(n->mac_table.macs);
3480     g_free(n->vlans);
3481 
3482     if (n->failover) {
3483         device_listener_unregister(&n->primary_listener);
3484         remove_migration_state_change_notifier(&n->migration_state);
3485     }
3486 
3487     max_queues = n->multiqueue ? n->max_queues : 1;
3488     for (i = 0; i < max_queues; i++) {
3489         virtio_net_del_queue(n, i);
3490     }
3491     /* delete also control vq */
3492     virtio_del_queue(vdev, max_queues * 2);
3493     qemu_announce_timer_del(&n->announce_timer, false);
3494     g_free(n->vqs);
3495     qemu_del_nic(n->nic);
3496     virtio_net_rsc_cleanup(n);
3497     g_free(n->rss_data.indirections_table);
3498     net_rx_pkt_uninit(n->rx_pkt);
3499     virtio_cleanup(vdev);
3500 }
3501 
3502 static void virtio_net_instance_init(Object *obj)
3503 {
3504     VirtIONet *n = VIRTIO_NET(obj);
3505 
3506     /*
3507      * The default config_size is sizeof(struct virtio_net_config).
3508      * Can be overriden with virtio_net_set_config_size.
3509      */
3510     n->config_size = sizeof(struct virtio_net_config);
3511     device_add_bootindex_property(obj, &n->nic_conf.bootindex,
3512                                   "bootindex", "/ethernet-phy@0",
3513                                   DEVICE(n));
3514 
3515     ebpf_rss_init(&n->ebpf_rss);
3516 }
3517 
3518 static int virtio_net_pre_save(void *opaque)
3519 {
3520     VirtIONet *n = opaque;
3521 
3522     /* At this point, backend must be stopped, otherwise
3523      * it might keep writing to memory. */
3524     assert(!n->vhost_started);
3525 
3526     return 0;
3527 }
3528 
3529 static bool primary_unplug_pending(void *opaque)
3530 {
3531     DeviceState *dev = opaque;
3532     DeviceState *primary;
3533     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
3534     VirtIONet *n = VIRTIO_NET(vdev);
3535 
3536     if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_STANDBY)) {
3537         return false;
3538     }
3539     primary = failover_find_primary_device(n);
3540     return primary ? primary->pending_deleted_event : false;
3541 }
3542 
3543 static bool dev_unplug_pending(void *opaque)
3544 {
3545     DeviceState *dev = opaque;
3546     VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(dev);
3547 
3548     return vdc->primary_unplug_pending(dev);
3549 }
3550 
3551 static const VMStateDescription vmstate_virtio_net = {
3552     .name = "virtio-net",
3553     .minimum_version_id = VIRTIO_NET_VM_VERSION,
3554     .version_id = VIRTIO_NET_VM_VERSION,
3555     .fields = (VMStateField[]) {
3556         VMSTATE_VIRTIO_DEVICE,
3557         VMSTATE_END_OF_LIST()
3558     },
3559     .pre_save = virtio_net_pre_save,
3560     .dev_unplug_pending = dev_unplug_pending,
3561 };
3562 
3563 static Property virtio_net_properties[] = {
3564     DEFINE_PROP_BIT64("csum", VirtIONet, host_features,
3565                     VIRTIO_NET_F_CSUM, true),
3566     DEFINE_PROP_BIT64("guest_csum", VirtIONet, host_features,
3567                     VIRTIO_NET_F_GUEST_CSUM, true),
3568     DEFINE_PROP_BIT64("gso", VirtIONet, host_features, VIRTIO_NET_F_GSO, true),
3569     DEFINE_PROP_BIT64("guest_tso4", VirtIONet, host_features,
3570                     VIRTIO_NET_F_GUEST_TSO4, true),
3571     DEFINE_PROP_BIT64("guest_tso6", VirtIONet, host_features,
3572                     VIRTIO_NET_F_GUEST_TSO6, true),
3573     DEFINE_PROP_BIT64("guest_ecn", VirtIONet, host_features,
3574                     VIRTIO_NET_F_GUEST_ECN, true),
3575     DEFINE_PROP_BIT64("guest_ufo", VirtIONet, host_features,
3576                     VIRTIO_NET_F_GUEST_UFO, true),
3577     DEFINE_PROP_BIT64("guest_announce", VirtIONet, host_features,
3578                     VIRTIO_NET_F_GUEST_ANNOUNCE, true),
3579     DEFINE_PROP_BIT64("host_tso4", VirtIONet, host_features,
3580                     VIRTIO_NET_F_HOST_TSO4, true),
3581     DEFINE_PROP_BIT64("host_tso6", VirtIONet, host_features,
3582                     VIRTIO_NET_F_HOST_TSO6, true),
3583     DEFINE_PROP_BIT64("host_ecn", VirtIONet, host_features,
3584                     VIRTIO_NET_F_HOST_ECN, true),
3585     DEFINE_PROP_BIT64("host_ufo", VirtIONet, host_features,
3586                     VIRTIO_NET_F_HOST_UFO, true),
3587     DEFINE_PROP_BIT64("mrg_rxbuf", VirtIONet, host_features,
3588                     VIRTIO_NET_F_MRG_RXBUF, true),
3589     DEFINE_PROP_BIT64("status", VirtIONet, host_features,
3590                     VIRTIO_NET_F_STATUS, true),
3591     DEFINE_PROP_BIT64("ctrl_vq", VirtIONet, host_features,
3592                     VIRTIO_NET_F_CTRL_VQ, true),
3593     DEFINE_PROP_BIT64("ctrl_rx", VirtIONet, host_features,
3594                     VIRTIO_NET_F_CTRL_RX, true),
3595     DEFINE_PROP_BIT64("ctrl_vlan", VirtIONet, host_features,
3596                     VIRTIO_NET_F_CTRL_VLAN, true),
3597     DEFINE_PROP_BIT64("ctrl_rx_extra", VirtIONet, host_features,
3598                     VIRTIO_NET_F_CTRL_RX_EXTRA, true),
3599     DEFINE_PROP_BIT64("ctrl_mac_addr", VirtIONet, host_features,
3600                     VIRTIO_NET_F_CTRL_MAC_ADDR, true),
3601     DEFINE_PROP_BIT64("ctrl_guest_offloads", VirtIONet, host_features,
3602                     VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, true),
3603     DEFINE_PROP_BIT64("mq", VirtIONet, host_features, VIRTIO_NET_F_MQ, false),
3604     DEFINE_PROP_BIT64("rss", VirtIONet, host_features,
3605                     VIRTIO_NET_F_RSS, false),
3606     DEFINE_PROP_BIT64("hash", VirtIONet, host_features,
3607                     VIRTIO_NET_F_HASH_REPORT, false),
3608     DEFINE_PROP_BIT64("guest_rsc_ext", VirtIONet, host_features,
3609                     VIRTIO_NET_F_RSC_EXT, false),
3610     DEFINE_PROP_UINT32("rsc_interval", VirtIONet, rsc_timeout,
3611                        VIRTIO_NET_RSC_DEFAULT_INTERVAL),
3612     DEFINE_NIC_PROPERTIES(VirtIONet, nic_conf),
3613     DEFINE_PROP_UINT32("x-txtimer", VirtIONet, net_conf.txtimer,
3614                        TX_TIMER_INTERVAL),
3615     DEFINE_PROP_INT32("x-txburst", VirtIONet, net_conf.txburst, TX_BURST),
3616     DEFINE_PROP_STRING("tx", VirtIONet, net_conf.tx),
3617     DEFINE_PROP_UINT16("rx_queue_size", VirtIONet, net_conf.rx_queue_size,
3618                        VIRTIO_NET_RX_QUEUE_DEFAULT_SIZE),
3619     DEFINE_PROP_UINT16("tx_queue_size", VirtIONet, net_conf.tx_queue_size,
3620                        VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE),
3621     DEFINE_PROP_UINT16("host_mtu", VirtIONet, net_conf.mtu, 0),
3622     DEFINE_PROP_BOOL("x-mtu-bypass-backend", VirtIONet, mtu_bypass_backend,
3623                      true),
3624     DEFINE_PROP_INT32("speed", VirtIONet, net_conf.speed, SPEED_UNKNOWN),
3625     DEFINE_PROP_STRING("duplex", VirtIONet, net_conf.duplex_str),
3626     DEFINE_PROP_BOOL("failover", VirtIONet, failover, false),
3627     DEFINE_PROP_END_OF_LIST(),
3628 };
3629 
3630 static void virtio_net_class_init(ObjectClass *klass, void *data)
3631 {
3632     DeviceClass *dc = DEVICE_CLASS(klass);
3633     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
3634 
3635     device_class_set_props(dc, virtio_net_properties);
3636     dc->vmsd = &vmstate_virtio_net;
3637     set_bit(DEVICE_CATEGORY_NETWORK, dc->categories);
3638     vdc->realize = virtio_net_device_realize;
3639     vdc->unrealize = virtio_net_device_unrealize;
3640     vdc->get_config = virtio_net_get_config;
3641     vdc->set_config = virtio_net_set_config;
3642     vdc->get_features = virtio_net_get_features;
3643     vdc->set_features = virtio_net_set_features;
3644     vdc->bad_features = virtio_net_bad_features;
3645     vdc->reset = virtio_net_reset;
3646     vdc->set_status = virtio_net_set_status;
3647     vdc->guest_notifier_mask = virtio_net_guest_notifier_mask;
3648     vdc->guest_notifier_pending = virtio_net_guest_notifier_pending;
3649     vdc->legacy_features |= (0x1 << VIRTIO_NET_F_GSO);
3650     vdc->post_load = virtio_net_post_load_virtio;
3651     vdc->vmsd = &vmstate_virtio_net_device;
3652     vdc->primary_unplug_pending = primary_unplug_pending;
3653 }
3654 
3655 static const TypeInfo virtio_net_info = {
3656     .name = TYPE_VIRTIO_NET,
3657     .parent = TYPE_VIRTIO_DEVICE,
3658     .instance_size = sizeof(VirtIONet),
3659     .instance_init = virtio_net_instance_init,
3660     .class_init = virtio_net_class_init,
3661 };
3662 
3663 static void virtio_register_types(void)
3664 {
3665     type_register_static(&virtio_net_info);
3666 }
3667 
3668 type_init(virtio_register_types)
3669