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1
/*
2
 * Virtio Network Device
3
 *
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 * Copyright IBM, Corp. 2007
5
 *
6
 * Authors:
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 *  Anthony Liguori   <aliguori@us.ibm.com>
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 *
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 * This work is licensed under the terms of the GNU GPL, version 2.  See
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 * the COPYING file in the top-level directory.
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 *
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 */
13

    
14
#include "qemu/iov.h"
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#include "virtio.h"
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#include "net/net.h"
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#include "net/checksum.h"
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#include "net/tap.h"
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#include "qemu/error-report.h"
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#include "qemu/timer.h"
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#include "virtio-net.h"
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#include "vhost_net.h"
23

    
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#define VIRTIO_NET_VM_VERSION    11
25

    
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#define MAC_TABLE_ENTRIES    64
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#define MAX_VLAN    (1 << 12)   /* Per 802.1Q definition */
28

    
29
typedef struct VirtIONet
30
{
31
    VirtIODevice vdev;
32
    uint8_t mac[ETH_ALEN];
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    uint16_t status;
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    VirtQueue *rx_vq;
35
    VirtQueue *tx_vq;
36
    VirtQueue *ctrl_vq;
37
    NICState *nic;
38
    QEMUTimer *tx_timer;
39
    QEMUBH *tx_bh;
40
    uint32_t tx_timeout;
41
    int32_t tx_burst;
42
    int tx_waiting;
43
    uint32_t has_vnet_hdr;
44
    size_t host_hdr_len;
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    size_t guest_hdr_len;
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    uint8_t has_ufo;
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    struct {
48
        VirtQueueElement elem;
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        ssize_t len;
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    } async_tx;
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    int mergeable_rx_bufs;
52
    uint8_t promisc;
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    uint8_t allmulti;
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    uint8_t alluni;
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    uint8_t nomulti;
56
    uint8_t nouni;
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    uint8_t nobcast;
58
    uint8_t vhost_started;
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    struct {
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        int in_use;
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        int first_multi;
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        uint8_t multi_overflow;
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        uint8_t uni_overflow;
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        uint8_t *macs;
65
    } mac_table;
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    uint32_t *vlans;
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    DeviceState *qdev;
68
} VirtIONet;
69

    
70
/* TODO
71
 * - we could suppress RX interrupt if we were so inclined.
72
 */
73

    
74
static VirtIONet *to_virtio_net(VirtIODevice *vdev)
75
{
76
    return (VirtIONet *)vdev;
77
}
78

    
79
static void virtio_net_get_config(VirtIODevice *vdev, uint8_t *config)
80
{
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    VirtIONet *n = to_virtio_net(vdev);
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    struct virtio_net_config netcfg;
83

    
84
    stw_p(&netcfg.status, n->status);
85
    memcpy(netcfg.mac, n->mac, ETH_ALEN);
86
    memcpy(config, &netcfg, sizeof(netcfg));
87
}
88

    
89
static void virtio_net_set_config(VirtIODevice *vdev, const uint8_t *config)
90
{
91
    VirtIONet *n = to_virtio_net(vdev);
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    struct virtio_net_config netcfg;
93

    
94
    memcpy(&netcfg, config, sizeof(netcfg));
95

    
96
    if (!(n->vdev.guest_features >> VIRTIO_NET_F_CTRL_MAC_ADDR & 1) &&
97
        memcmp(netcfg.mac, n->mac, ETH_ALEN)) {
98
        memcpy(n->mac, netcfg.mac, ETH_ALEN);
99
        qemu_format_nic_info_str(qemu_get_queue(n->nic), n->mac);
100
    }
101
}
102

    
103
static bool virtio_net_started(VirtIONet *n, uint8_t status)
104
{
105
    return (status & VIRTIO_CONFIG_S_DRIVER_OK) &&
106
        (n->status & VIRTIO_NET_S_LINK_UP) && n->vdev.vm_running;
107
}
108

    
109
static void virtio_net_vhost_status(VirtIONet *n, uint8_t status)
110
{
111
    NetClientState *nc = qemu_get_queue(n->nic);
112

    
113
    if (!nc->peer) {
114
        return;
115
    }
116
    if (nc->peer->info->type != NET_CLIENT_OPTIONS_KIND_TAP) {
117
        return;
118
    }
119

    
120
    if (!tap_get_vhost_net(nc->peer)) {
121
        return;
122
    }
123
    if (!!n->vhost_started == virtio_net_started(n, status) &&
124
                              !nc->peer->link_down) {
125
        return;
126
    }
127
    if (!n->vhost_started) {
128
        int r;
129
        if (!vhost_net_query(tap_get_vhost_net(nc->peer), &n->vdev)) {
130
            return;
131
        }
132
        n->vhost_started = 1;
133
        r = vhost_net_start(tap_get_vhost_net(nc->peer), &n->vdev);
134
        if (r < 0) {
135
            error_report("unable to start vhost net: %d: "
136
                         "falling back on userspace virtio", -r);
137
            n->vhost_started = 0;
138
        }
139
    } else {
140
        vhost_net_stop(tap_get_vhost_net(nc->peer), &n->vdev);
141
        n->vhost_started = 0;
142
    }
143
}
144

    
145
static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status)
146
{
147
    VirtIONet *n = to_virtio_net(vdev);
148

    
149
    virtio_net_vhost_status(n, status);
150

    
151
    if (!n->tx_waiting) {
152
        return;
153
    }
154

    
155
    if (virtio_net_started(n, status) && !n->vhost_started) {
156
        if (n->tx_timer) {
157
            qemu_mod_timer(n->tx_timer,
158
                           qemu_get_clock_ns(vm_clock) + n->tx_timeout);
159
        } else {
160
            qemu_bh_schedule(n->tx_bh);
161
        }
162
    } else {
163
        if (n->tx_timer) {
164
            qemu_del_timer(n->tx_timer);
165
        } else {
166
            qemu_bh_cancel(n->tx_bh);
167
        }
168
    }
169
}
170

    
171
static void virtio_net_set_link_status(NetClientState *nc)
172
{
173
    VirtIONet *n = qemu_get_nic_opaque(nc);
174
    uint16_t old_status = n->status;
175

    
176
    if (nc->link_down)
177
        n->status &= ~VIRTIO_NET_S_LINK_UP;
178
    else
179
        n->status |= VIRTIO_NET_S_LINK_UP;
180

    
181
    if (n->status != old_status)
182
        virtio_notify_config(&n->vdev);
183

    
184
    virtio_net_set_status(&n->vdev, n->vdev.status);
185
}
186

    
187
static void virtio_net_reset(VirtIODevice *vdev)
188
{
189
    VirtIONet *n = to_virtio_net(vdev);
190

    
191
    /* Reset back to compatibility mode */
192
    n->promisc = 1;
193
    n->allmulti = 0;
194
    n->alluni = 0;
195
    n->nomulti = 0;
196
    n->nouni = 0;
197
    n->nobcast = 0;
198

    
199
    /* Flush any MAC and VLAN filter table state */
200
    n->mac_table.in_use = 0;
201
    n->mac_table.first_multi = 0;
202
    n->mac_table.multi_overflow = 0;
203
    n->mac_table.uni_overflow = 0;
204
    memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
205
    memcpy(&n->mac[0], &n->nic->conf->macaddr, sizeof(n->mac));
206
    memset(n->vlans, 0, MAX_VLAN >> 3);
207
}
208

    
209
static void peer_test_vnet_hdr(VirtIONet *n)
210
{
211
    NetClientState *nc = qemu_get_queue(n->nic);
212
    if (!nc->peer) {
213
        return;
214
    }
215

    
216
    if (nc->peer->info->type != NET_CLIENT_OPTIONS_KIND_TAP) {
217
        return;
218
    }
219

    
220
    n->has_vnet_hdr = tap_has_vnet_hdr(nc->peer);
221
}
222

    
223
static int peer_has_vnet_hdr(VirtIONet *n)
224
{
225
    return n->has_vnet_hdr;
226
}
227

    
228
static int peer_has_ufo(VirtIONet *n)
229
{
230
    if (!peer_has_vnet_hdr(n))
231
        return 0;
232

    
233
    n->has_ufo = tap_has_ufo(qemu_get_queue(n->nic)->peer);
234

    
235
    return n->has_ufo;
236
}
237

    
238
static void virtio_net_set_mrg_rx_bufs(VirtIONet *n, int mergeable_rx_bufs)
239
{
240
    n->mergeable_rx_bufs = mergeable_rx_bufs;
241

    
242
    n->guest_hdr_len = n->mergeable_rx_bufs ?
243
        sizeof(struct virtio_net_hdr_mrg_rxbuf) : sizeof(struct virtio_net_hdr);
244

    
245
    if (peer_has_vnet_hdr(n) &&
246
        tap_has_vnet_hdr_len(qemu_get_queue(n->nic)->peer, n->guest_hdr_len)) {
247
        tap_set_vnet_hdr_len(qemu_get_queue(n->nic)->peer, n->guest_hdr_len);
248
        n->host_hdr_len = n->guest_hdr_len;
249
    }
250
}
251

    
252
static uint32_t virtio_net_get_features(VirtIODevice *vdev, uint32_t features)
253
{
254
    VirtIONet *n = to_virtio_net(vdev);
255
    NetClientState *nc = qemu_get_queue(n->nic);
256

    
257
    features |= (1 << VIRTIO_NET_F_MAC);
258

    
259
    if (!peer_has_vnet_hdr(n)) {
260
        features &= ~(0x1 << VIRTIO_NET_F_CSUM);
261
        features &= ~(0x1 << VIRTIO_NET_F_HOST_TSO4);
262
        features &= ~(0x1 << VIRTIO_NET_F_HOST_TSO6);
263
        features &= ~(0x1 << VIRTIO_NET_F_HOST_ECN);
264

    
265
        features &= ~(0x1 << VIRTIO_NET_F_GUEST_CSUM);
266
        features &= ~(0x1 << VIRTIO_NET_F_GUEST_TSO4);
267
        features &= ~(0x1 << VIRTIO_NET_F_GUEST_TSO6);
268
        features &= ~(0x1 << VIRTIO_NET_F_GUEST_ECN);
269
    }
270

    
271
    if (!peer_has_vnet_hdr(n) || !peer_has_ufo(n)) {
272
        features &= ~(0x1 << VIRTIO_NET_F_GUEST_UFO);
273
        features &= ~(0x1 << VIRTIO_NET_F_HOST_UFO);
274
    }
275

    
276
    if (!nc->peer || nc->peer->info->type != NET_CLIENT_OPTIONS_KIND_TAP) {
277
        return features;
278
    }
279
    if (!tap_get_vhost_net(nc->peer)) {
280
        return features;
281
    }
282
    return vhost_net_get_features(tap_get_vhost_net(nc->peer), features);
283
}
284

    
285
static uint32_t virtio_net_bad_features(VirtIODevice *vdev)
286
{
287
    uint32_t features = 0;
288

    
289
    /* Linux kernel 2.6.25.  It understood MAC (as everyone must),
290
     * but also these: */
291
    features |= (1 << VIRTIO_NET_F_MAC);
292
    features |= (1 << VIRTIO_NET_F_CSUM);
293
    features |= (1 << VIRTIO_NET_F_HOST_TSO4);
294
    features |= (1 << VIRTIO_NET_F_HOST_TSO6);
295
    features |= (1 << VIRTIO_NET_F_HOST_ECN);
296

    
297
    return features;
298
}
299

    
300
static void virtio_net_set_features(VirtIODevice *vdev, uint32_t features)
301
{
302
    VirtIONet *n = to_virtio_net(vdev);
303
    NetClientState *nc = qemu_get_queue(n->nic);
304

    
305
    virtio_net_set_mrg_rx_bufs(n, !!(features & (1 << VIRTIO_NET_F_MRG_RXBUF)));
306

    
307
    if (n->has_vnet_hdr) {
308
        tap_set_offload(nc->peer,
309
                        (features >> VIRTIO_NET_F_GUEST_CSUM) & 1,
310
                        (features >> VIRTIO_NET_F_GUEST_TSO4) & 1,
311
                        (features >> VIRTIO_NET_F_GUEST_TSO6) & 1,
312
                        (features >> VIRTIO_NET_F_GUEST_ECN)  & 1,
313
                        (features >> VIRTIO_NET_F_GUEST_UFO)  & 1);
314
    }
315
    if (!nc->peer || nc->peer->info->type != NET_CLIENT_OPTIONS_KIND_TAP) {
316
        return;
317
    }
318
    if (!tap_get_vhost_net(nc->peer)) {
319
        return;
320
    }
321
    vhost_net_ack_features(tap_get_vhost_net(nc->peer), features);
322
}
323

    
324
static int virtio_net_handle_rx_mode(VirtIONet *n, uint8_t cmd,
325
                                     struct iovec *iov, unsigned int iov_cnt)
326
{
327
    uint8_t on;
328
    size_t s;
329

    
330
    s = iov_to_buf(iov, iov_cnt, 0, &on, sizeof(on));
331
    if (s != sizeof(on)) {
332
        return VIRTIO_NET_ERR;
333
    }
334

    
335
    if (cmd == VIRTIO_NET_CTRL_RX_PROMISC) {
336
        n->promisc = on;
337
    } else if (cmd == VIRTIO_NET_CTRL_RX_ALLMULTI) {
338
        n->allmulti = on;
339
    } else if (cmd == VIRTIO_NET_CTRL_RX_ALLUNI) {
340
        n->alluni = on;
341
    } else if (cmd == VIRTIO_NET_CTRL_RX_NOMULTI) {
342
        n->nomulti = on;
343
    } else if (cmd == VIRTIO_NET_CTRL_RX_NOUNI) {
344
        n->nouni = on;
345
    } else if (cmd == VIRTIO_NET_CTRL_RX_NOBCAST) {
346
        n->nobcast = on;
347
    } else {
348
        return VIRTIO_NET_ERR;
349
    }
350

    
351
    return VIRTIO_NET_OK;
352
}
353

    
354
static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd,
355
                                 struct iovec *iov, unsigned int iov_cnt)
356
{
357
    struct virtio_net_ctrl_mac mac_data;
358
    size_t s;
359

    
360
    if (cmd == VIRTIO_NET_CTRL_MAC_ADDR_SET) {
361
        if (iov_size(iov, iov_cnt) != sizeof(n->mac)) {
362
            return VIRTIO_NET_ERR;
363
        }
364
        s = iov_to_buf(iov, iov_cnt, 0, &n->mac, sizeof(n->mac));
365
        assert(s == sizeof(n->mac));
366
        qemu_format_nic_info_str(qemu_get_queue(n->nic), n->mac);
367
        return VIRTIO_NET_OK;
368
    }
369

    
370
    if (cmd != VIRTIO_NET_CTRL_MAC_TABLE_SET) {
371
        return VIRTIO_NET_ERR;
372
    }
373

    
374
    n->mac_table.in_use = 0;
375
    n->mac_table.first_multi = 0;
376
    n->mac_table.uni_overflow = 0;
377
    n->mac_table.multi_overflow = 0;
378
    memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
379

    
380
    s = iov_to_buf(iov, iov_cnt, 0, &mac_data.entries,
381
                   sizeof(mac_data.entries));
382
    mac_data.entries = ldl_p(&mac_data.entries);
383
    if (s != sizeof(mac_data.entries)) {
384
        return VIRTIO_NET_ERR;
385
    }
386
    iov_discard_front(&iov, &iov_cnt, s);
387

    
388
    if (mac_data.entries * ETH_ALEN > iov_size(iov, iov_cnt)) {
389
        return VIRTIO_NET_ERR;
390
    }
391

    
392
    if (mac_data.entries <= MAC_TABLE_ENTRIES) {
393
        s = iov_to_buf(iov, iov_cnt, 0, n->mac_table.macs,
394
                       mac_data.entries * ETH_ALEN);
395
        if (s != mac_data.entries * ETH_ALEN) {
396
            return VIRTIO_NET_ERR;
397
        }
398
        n->mac_table.in_use += mac_data.entries;
399
    } else {
400
        n->mac_table.uni_overflow = 1;
401
    }
402

    
403
    iov_discard_front(&iov, &iov_cnt, mac_data.entries * ETH_ALEN);
404

    
405
    n->mac_table.first_multi = n->mac_table.in_use;
406

    
407
    s = iov_to_buf(iov, iov_cnt, 0, &mac_data.entries,
408
                   sizeof(mac_data.entries));
409
    mac_data.entries = ldl_p(&mac_data.entries);
410
    if (s != sizeof(mac_data.entries)) {
411
        return VIRTIO_NET_ERR;
412
    }
413

    
414
    iov_discard_front(&iov, &iov_cnt, s);
415

    
416
    if (mac_data.entries * ETH_ALEN != iov_size(iov, iov_cnt)) {
417
        return VIRTIO_NET_ERR;
418
    }
419

    
420
    if (n->mac_table.in_use + mac_data.entries <= MAC_TABLE_ENTRIES) {
421
        s = iov_to_buf(iov, iov_cnt, 0, n->mac_table.macs,
422
                       mac_data.entries * ETH_ALEN);
423
        if (s != mac_data.entries * ETH_ALEN) {
424
            return VIRTIO_NET_ERR;
425
        }
426
        n->mac_table.in_use += mac_data.entries;
427
    } else {
428
        n->mac_table.multi_overflow = 1;
429
    }
430

    
431
    return VIRTIO_NET_OK;
432
}
433

    
434
static int virtio_net_handle_vlan_table(VirtIONet *n, uint8_t cmd,
435
                                        struct iovec *iov, unsigned int iov_cnt)
436
{
437
    uint16_t vid;
438
    size_t s;
439

    
440
    s = iov_to_buf(iov, iov_cnt, 0, &vid, sizeof(vid));
441
    vid = lduw_p(&vid);
442
    if (s != sizeof(vid)) {
443
        return VIRTIO_NET_ERR;
444
    }
445

    
446
    if (vid >= MAX_VLAN)
447
        return VIRTIO_NET_ERR;
448

    
449
    if (cmd == VIRTIO_NET_CTRL_VLAN_ADD)
450
        n->vlans[vid >> 5] |= (1U << (vid & 0x1f));
451
    else if (cmd == VIRTIO_NET_CTRL_VLAN_DEL)
452
        n->vlans[vid >> 5] &= ~(1U << (vid & 0x1f));
453
    else
454
        return VIRTIO_NET_ERR;
455

    
456
    return VIRTIO_NET_OK;
457
}
458

    
459
static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
460
{
461
    VirtIONet *n = to_virtio_net(vdev);
462
    struct virtio_net_ctrl_hdr ctrl;
463
    virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
464
    VirtQueueElement elem;
465
    size_t s;
466
    struct iovec *iov;
467
    unsigned int iov_cnt;
468

    
469
    while (virtqueue_pop(vq, &elem)) {
470
        if (iov_size(elem.in_sg, elem.in_num) < sizeof(status) ||
471
            iov_size(elem.out_sg, elem.out_num) < sizeof(ctrl)) {
472
            error_report("virtio-net ctrl missing headers");
473
            exit(1);
474
        }
475

    
476
        iov = elem.out_sg;
477
        iov_cnt = elem.out_num;
478
        s = iov_to_buf(iov, iov_cnt, 0, &ctrl, sizeof(ctrl));
479
        iov_discard_front(&iov, &iov_cnt, sizeof(ctrl));
480
        if (s != sizeof(ctrl)) {
481
            status = VIRTIO_NET_ERR;
482
        } else if (ctrl.class == VIRTIO_NET_CTRL_RX) {
483
            status = virtio_net_handle_rx_mode(n, ctrl.cmd, iov, iov_cnt);
484
        } else if (ctrl.class == VIRTIO_NET_CTRL_MAC) {
485
            status = virtio_net_handle_mac(n, ctrl.cmd, iov, iov_cnt);
486
        } else if (ctrl.class == VIRTIO_NET_CTRL_VLAN) {
487
            status = virtio_net_handle_vlan_table(n, ctrl.cmd, iov, iov_cnt);
488
        }
489

    
490
        s = iov_from_buf(elem.in_sg, elem.in_num, 0, &status, sizeof(status));
491
        assert(s == sizeof(status));
492

    
493
        virtqueue_push(vq, &elem, sizeof(status));
494
        virtio_notify(vdev, vq);
495
    }
496
}
497

    
498
/* RX */
499

    
500
static void virtio_net_handle_rx(VirtIODevice *vdev, VirtQueue *vq)
501
{
502
    VirtIONet *n = to_virtio_net(vdev);
503

    
504
    qemu_flush_queued_packets(qemu_get_queue(n->nic));
505
}
506

    
507
static int virtio_net_can_receive(NetClientState *nc)
508
{
509
    VirtIONet *n = qemu_get_nic_opaque(nc);
510
    if (!n->vdev.vm_running) {
511
        return 0;
512
    }
513

    
514
    if (!virtio_queue_ready(n->rx_vq) ||
515
        !(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
516
        return 0;
517

    
518
    return 1;
519
}
520

    
521
static int virtio_net_has_buffers(VirtIONet *n, int bufsize)
522
{
523
    if (virtio_queue_empty(n->rx_vq) ||
524
        (n->mergeable_rx_bufs &&
525
         !virtqueue_avail_bytes(n->rx_vq, bufsize, 0))) {
526
        virtio_queue_set_notification(n->rx_vq, 1);
527

    
528
        /* To avoid a race condition where the guest has made some buffers
529
         * available after the above check but before notification was
530
         * enabled, check for available buffers again.
531
         */
532
        if (virtio_queue_empty(n->rx_vq) ||
533
            (n->mergeable_rx_bufs &&
534
             !virtqueue_avail_bytes(n->rx_vq, bufsize, 0)))
535
            return 0;
536
    }
537

    
538
    virtio_queue_set_notification(n->rx_vq, 0);
539
    return 1;
540
}
541

    
542
/* dhclient uses AF_PACKET but doesn't pass auxdata to the kernel so
543
 * it never finds out that the packets don't have valid checksums.  This
544
 * causes dhclient to get upset.  Fedora's carried a patch for ages to
545
 * fix this with Xen but it hasn't appeared in an upstream release of
546
 * dhclient yet.
547
 *
548
 * To avoid breaking existing guests, we catch udp packets and add
549
 * checksums.  This is terrible but it's better than hacking the guest
550
 * kernels.
551
 *
552
 * N.B. if we introduce a zero-copy API, this operation is no longer free so
553
 * we should provide a mechanism to disable it to avoid polluting the host
554
 * cache.
555
 */
556
static void work_around_broken_dhclient(struct virtio_net_hdr *hdr,
557
                                        uint8_t *buf, size_t size)
558
{
559
    if ((hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && /* missing csum */
560
        (size > 27 && size < 1500) && /* normal sized MTU */
561
        (buf[12] == 0x08 && buf[13] == 0x00) && /* ethertype == IPv4 */
562
        (buf[23] == 17) && /* ip.protocol == UDP */
563
        (buf[34] == 0 && buf[35] == 67)) { /* udp.srcport == bootps */
564
        net_checksum_calculate(buf, size);
565
        hdr->flags &= ~VIRTIO_NET_HDR_F_NEEDS_CSUM;
566
    }
567
}
568

    
569
static void receive_header(VirtIONet *n, const struct iovec *iov, int iov_cnt,
570
                           const void *buf, size_t size)
571
{
572
    if (n->has_vnet_hdr) {
573
        /* FIXME this cast is evil */
574
        void *wbuf = (void *)buf;
575
        work_around_broken_dhclient(wbuf, wbuf + n->host_hdr_len,
576
                                    size - n->host_hdr_len);
577
        iov_from_buf(iov, iov_cnt, 0, buf, sizeof(struct virtio_net_hdr));
578
    } else {
579
        struct virtio_net_hdr hdr = {
580
            .flags = 0,
581
            .gso_type = VIRTIO_NET_HDR_GSO_NONE
582
        };
583
        iov_from_buf(iov, iov_cnt, 0, &hdr, sizeof hdr);
584
    }
585
}
586

    
587
static int receive_filter(VirtIONet *n, const uint8_t *buf, int size)
588
{
589
    static const uint8_t bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
590
    static const uint8_t vlan[] = {0x81, 0x00};
591
    uint8_t *ptr = (uint8_t *)buf;
592
    int i;
593

    
594
    if (n->promisc)
595
        return 1;
596

    
597
    ptr += n->host_hdr_len;
598

    
599
    if (!memcmp(&ptr[12], vlan, sizeof(vlan))) {
600
        int vid = be16_to_cpup((uint16_t *)(ptr + 14)) & 0xfff;
601
        if (!(n->vlans[vid >> 5] & (1U << (vid & 0x1f))))
602
            return 0;
603
    }
604

    
605
    if (ptr[0] & 1) { // multicast
606
        if (!memcmp(ptr, bcast, sizeof(bcast))) {
607
            return !n->nobcast;
608
        } else if (n->nomulti) {
609
            return 0;
610
        } else if (n->allmulti || n->mac_table.multi_overflow) {
611
            return 1;
612
        }
613

    
614
        for (i = n->mac_table.first_multi; i < n->mac_table.in_use; i++) {
615
            if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN)) {
616
                return 1;
617
            }
618
        }
619
    } else { // unicast
620
        if (n->nouni) {
621
            return 0;
622
        } else if (n->alluni || n->mac_table.uni_overflow) {
623
            return 1;
624
        } else if (!memcmp(ptr, n->mac, ETH_ALEN)) {
625
            return 1;
626
        }
627

    
628
        for (i = 0; i < n->mac_table.first_multi; i++) {
629
            if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN)) {
630
                return 1;
631
            }
632
        }
633
    }
634

    
635
    return 0;
636
}
637

    
638
static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf, size_t size)
639
{
640
    VirtIONet *n = qemu_get_nic_opaque(nc);
641
    struct iovec mhdr_sg[VIRTQUEUE_MAX_SIZE];
642
    struct virtio_net_hdr_mrg_rxbuf mhdr;
643
    unsigned mhdr_cnt = 0;
644
    size_t offset, i, guest_offset;
645

    
646
    if (!virtio_net_can_receive(qemu_get_queue(n->nic))) {
647
        return -1;
648
    }
649

    
650
    /* hdr_len refers to the header we supply to the guest */
651
    if (!virtio_net_has_buffers(n, size + n->guest_hdr_len - n->host_hdr_len))
652
        return 0;
653

    
654
    if (!receive_filter(n, buf, size))
655
        return size;
656

    
657
    offset = i = 0;
658

    
659
    while (offset < size) {
660
        VirtQueueElement elem;
661
        int len, total;
662
        const struct iovec *sg = elem.in_sg;
663

    
664
        total = 0;
665

    
666
        if (virtqueue_pop(n->rx_vq, &elem) == 0) {
667
            if (i == 0)
668
                return -1;
669
            error_report("virtio-net unexpected empty queue: "
670
                    "i %zd mergeable %d offset %zd, size %zd, "
671
                    "guest hdr len %zd, host hdr len %zd guest features 0x%x",
672
                    i, n->mergeable_rx_bufs, offset, size,
673
                    n->guest_hdr_len, n->host_hdr_len, n->vdev.guest_features);
674
            exit(1);
675
        }
676

    
677
        if (elem.in_num < 1) {
678
            error_report("virtio-net receive queue contains no in buffers");
679
            exit(1);
680
        }
681

    
682
        if (i == 0) {
683
            assert(offset == 0);
684
            if (n->mergeable_rx_bufs) {
685
                mhdr_cnt = iov_copy(mhdr_sg, ARRAY_SIZE(mhdr_sg),
686
                                    sg, elem.in_num,
687
                                    offsetof(typeof(mhdr), num_buffers),
688
                                    sizeof(mhdr.num_buffers));
689
            }
690

    
691
            receive_header(n, sg, elem.in_num, buf, size);
692
            offset = n->host_hdr_len;
693
            total += n->guest_hdr_len;
694
            guest_offset = n->guest_hdr_len;
695
        } else {
696
            guest_offset = 0;
697
        }
698

    
699
        /* copy in packet.  ugh */
700
        len = iov_from_buf(sg, elem.in_num, guest_offset,
701
                           buf + offset, size - offset);
702
        total += len;
703
        offset += len;
704
        /* If buffers can't be merged, at this point we
705
         * must have consumed the complete packet.
706
         * Otherwise, drop it. */
707
        if (!n->mergeable_rx_bufs && offset < size) {
708
#if 0
709
            error_report("virtio-net truncated non-mergeable packet: "
710
                         "i %zd mergeable %d offset %zd, size %zd, "
711
                         "guest hdr len %zd, host hdr len %zd",
712
                         i, n->mergeable_rx_bufs,
713
                         offset, size, n->guest_hdr_len, n->host_hdr_len);
714
#endif
715
            return size;
716
        }
717

    
718
        /* signal other side */
719
        virtqueue_fill(n->rx_vq, &elem, total, i++);
720
    }
721

    
722
    if (mhdr_cnt) {
723
        stw_p(&mhdr.num_buffers, i);
724
        iov_from_buf(mhdr_sg, mhdr_cnt,
725
                     0,
726
                     &mhdr.num_buffers, sizeof mhdr.num_buffers);
727
    }
728

    
729
    virtqueue_flush(n->rx_vq, i);
730
    virtio_notify(&n->vdev, n->rx_vq);
731

    
732
    return size;
733
}
734

    
735
static int32_t virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq);
736

    
737
static void virtio_net_tx_complete(NetClientState *nc, ssize_t len)
738
{
739
    VirtIONet *n = qemu_get_nic_opaque(nc);
740

    
741
    virtqueue_push(n->tx_vq, &n->async_tx.elem, 0);
742
    virtio_notify(&n->vdev, n->tx_vq);
743

    
744
    n->async_tx.elem.out_num = n->async_tx.len = 0;
745

    
746
    virtio_queue_set_notification(n->tx_vq, 1);
747
    virtio_net_flush_tx(n, n->tx_vq);
748
}
749

    
750
/* TX */
751
static int32_t virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq)
752
{
753
    VirtQueueElement elem;
754
    int32_t num_packets = 0;
755
    if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK)) {
756
        return num_packets;
757
    }
758

    
759
    assert(n->vdev.vm_running);
760

    
761
    if (n->async_tx.elem.out_num) {
762
        virtio_queue_set_notification(n->tx_vq, 0);
763
        return num_packets;
764
    }
765

    
766
    while (virtqueue_pop(vq, &elem)) {
767
        ssize_t ret, len;
768
        unsigned int out_num = elem.out_num;
769
        struct iovec *out_sg = &elem.out_sg[0];
770
        struct iovec sg[VIRTQUEUE_MAX_SIZE];
771

    
772
        if (out_num < 1) {
773
            error_report("virtio-net header not in first element");
774
            exit(1);
775
        }
776

    
777
        /*
778
         * If host wants to see the guest header as is, we can
779
         * pass it on unchanged. Otherwise, copy just the parts
780
         * that host is interested in.
781
         */
782
        assert(n->host_hdr_len <= n->guest_hdr_len);
783
        if (n->host_hdr_len != n->guest_hdr_len) {
784
            unsigned sg_num = iov_copy(sg, ARRAY_SIZE(sg),
785
                                       out_sg, out_num,
786
                                       0, n->host_hdr_len);
787
            sg_num += iov_copy(sg + sg_num, ARRAY_SIZE(sg) - sg_num,
788
                             out_sg, out_num,
789
                             n->guest_hdr_len, -1);
790
            out_num = sg_num;
791
            out_sg = sg;
792
        }
793

    
794
        len = n->guest_hdr_len;
795

    
796
        ret = qemu_sendv_packet_async(qemu_get_queue(n->nic), out_sg, out_num,
797
                                      virtio_net_tx_complete);
798
        if (ret == 0) {
799
            virtio_queue_set_notification(n->tx_vq, 0);
800
            n->async_tx.elem = elem;
801
            n->async_tx.len  = len;
802
            return -EBUSY;
803
        }
804

    
805
        len += ret;
806

    
807
        virtqueue_push(vq, &elem, 0);
808
        virtio_notify(&n->vdev, vq);
809

    
810
        if (++num_packets >= n->tx_burst) {
811
            break;
812
        }
813
    }
814
    return num_packets;
815
}
816

    
817
static void virtio_net_handle_tx_timer(VirtIODevice *vdev, VirtQueue *vq)
818
{
819
    VirtIONet *n = to_virtio_net(vdev);
820

    
821
    /* This happens when device was stopped but VCPU wasn't. */
822
    if (!n->vdev.vm_running) {
823
        n->tx_waiting = 1;
824
        return;
825
    }
826

    
827
    if (n->tx_waiting) {
828
        virtio_queue_set_notification(vq, 1);
829
        qemu_del_timer(n->tx_timer);
830
        n->tx_waiting = 0;
831
        virtio_net_flush_tx(n, vq);
832
    } else {
833
        qemu_mod_timer(n->tx_timer,
834
                       qemu_get_clock_ns(vm_clock) + n->tx_timeout);
835
        n->tx_waiting = 1;
836
        virtio_queue_set_notification(vq, 0);
837
    }
838
}
839

    
840
static void virtio_net_handle_tx_bh(VirtIODevice *vdev, VirtQueue *vq)
841
{
842
    VirtIONet *n = to_virtio_net(vdev);
843

    
844
    if (unlikely(n->tx_waiting)) {
845
        return;
846
    }
847
    n->tx_waiting = 1;
848
    /* This happens when device was stopped but VCPU wasn't. */
849
    if (!n->vdev.vm_running) {
850
        return;
851
    }
852
    virtio_queue_set_notification(vq, 0);
853
    qemu_bh_schedule(n->tx_bh);
854
}
855

    
856
static void virtio_net_tx_timer(void *opaque)
857
{
858
    VirtIONet *n = opaque;
859
    assert(n->vdev.vm_running);
860

    
861
    n->tx_waiting = 0;
862

    
863
    /* Just in case the driver is not ready on more */
864
    if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
865
        return;
866

    
867
    virtio_queue_set_notification(n->tx_vq, 1);
868
    virtio_net_flush_tx(n, n->tx_vq);
869
}
870

    
871
static void virtio_net_tx_bh(void *opaque)
872
{
873
    VirtIONet *n = opaque;
874
    int32_t ret;
875

    
876
    assert(n->vdev.vm_running);
877

    
878
    n->tx_waiting = 0;
879

    
880
    /* Just in case the driver is not ready on more */
881
    if (unlikely(!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK)))
882
        return;
883

    
884
    ret = virtio_net_flush_tx(n, n->tx_vq);
885
    if (ret == -EBUSY) {
886
        return; /* Notification re-enable handled by tx_complete */
887
    }
888

    
889
    /* If we flush a full burst of packets, assume there are
890
     * more coming and immediately reschedule */
891
    if (ret >= n->tx_burst) {
892
        qemu_bh_schedule(n->tx_bh);
893
        n->tx_waiting = 1;
894
        return;
895
    }
896

    
897
    /* If less than a full burst, re-enable notification and flush
898
     * anything that may have come in while we weren't looking.  If
899
     * we find something, assume the guest is still active and reschedule */
900
    virtio_queue_set_notification(n->tx_vq, 1);
901
    if (virtio_net_flush_tx(n, n->tx_vq) > 0) {
902
        virtio_queue_set_notification(n->tx_vq, 0);
903
        qemu_bh_schedule(n->tx_bh);
904
        n->tx_waiting = 1;
905
    }
906
}
907

    
908
static void virtio_net_save(QEMUFile *f, void *opaque)
909
{
910
    VirtIONet *n = opaque;
911

    
912
    /* At this point, backend must be stopped, otherwise
913
     * it might keep writing to memory. */
914
    assert(!n->vhost_started);
915
    virtio_save(&n->vdev, f);
916

    
917
    qemu_put_buffer(f, n->mac, ETH_ALEN);
918
    qemu_put_be32(f, n->tx_waiting);
919
    qemu_put_be32(f, n->mergeable_rx_bufs);
920
    qemu_put_be16(f, n->status);
921
    qemu_put_byte(f, n->promisc);
922
    qemu_put_byte(f, n->allmulti);
923
    qemu_put_be32(f, n->mac_table.in_use);
924
    qemu_put_buffer(f, n->mac_table.macs, n->mac_table.in_use * ETH_ALEN);
925
    qemu_put_buffer(f, (uint8_t *)n->vlans, MAX_VLAN >> 3);
926
    qemu_put_be32(f, n->has_vnet_hdr);
927
    qemu_put_byte(f, n->mac_table.multi_overflow);
928
    qemu_put_byte(f, n->mac_table.uni_overflow);
929
    qemu_put_byte(f, n->alluni);
930
    qemu_put_byte(f, n->nomulti);
931
    qemu_put_byte(f, n->nouni);
932
    qemu_put_byte(f, n->nobcast);
933
    qemu_put_byte(f, n->has_ufo);
934
}
935

    
936
static int virtio_net_load(QEMUFile *f, void *opaque, int version_id)
937
{
938
    VirtIONet *n = opaque;
939
    int i;
940
    int ret;
941

    
942
    if (version_id < 2 || version_id > VIRTIO_NET_VM_VERSION)
943
        return -EINVAL;
944

    
945
    ret = virtio_load(&n->vdev, f);
946
    if (ret) {
947
        return ret;
948
    }
949

    
950
    qemu_get_buffer(f, n->mac, ETH_ALEN);
951
    n->tx_waiting = qemu_get_be32(f);
952

    
953
    virtio_net_set_mrg_rx_bufs(n, qemu_get_be32(f));
954

    
955
    if (version_id >= 3)
956
        n->status = qemu_get_be16(f);
957

    
958
    if (version_id >= 4) {
959
        if (version_id < 8) {
960
            n->promisc = qemu_get_be32(f);
961
            n->allmulti = qemu_get_be32(f);
962
        } else {
963
            n->promisc = qemu_get_byte(f);
964
            n->allmulti = qemu_get_byte(f);
965
        }
966
    }
967

    
968
    if (version_id >= 5) {
969
        n->mac_table.in_use = qemu_get_be32(f);
970
        /* MAC_TABLE_ENTRIES may be different from the saved image */
971
        if (n->mac_table.in_use <= MAC_TABLE_ENTRIES) {
972
            qemu_get_buffer(f, n->mac_table.macs,
973
                            n->mac_table.in_use * ETH_ALEN);
974
        } else if (n->mac_table.in_use) {
975
            uint8_t *buf = g_malloc0(n->mac_table.in_use);
976
            qemu_get_buffer(f, buf, n->mac_table.in_use * ETH_ALEN);
977
            g_free(buf);
978
            n->mac_table.multi_overflow = n->mac_table.uni_overflow = 1;
979
            n->mac_table.in_use = 0;
980
        }
981
    }
982
 
983
    if (version_id >= 6)
984
        qemu_get_buffer(f, (uint8_t *)n->vlans, MAX_VLAN >> 3);
985

    
986
    if (version_id >= 7) {
987
        if (qemu_get_be32(f) && !peer_has_vnet_hdr(n)) {
988
            error_report("virtio-net: saved image requires vnet_hdr=on");
989
            return -1;
990
        }
991

    
992
        if (n->has_vnet_hdr) {
993
            tap_set_offload(qemu_get_queue(n->nic)->peer,
994
                    (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_CSUM) & 1,
995
                    (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_TSO4) & 1,
996
                    (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_TSO6) & 1,
997
                    (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_ECN)  & 1,
998
                    (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_UFO)  & 1);
999
        }
1000
    }
1001

    
1002
    if (version_id >= 9) {
1003
        n->mac_table.multi_overflow = qemu_get_byte(f);
1004
        n->mac_table.uni_overflow = qemu_get_byte(f);
1005
    }
1006

    
1007
    if (version_id >= 10) {
1008
        n->alluni = qemu_get_byte(f);
1009
        n->nomulti = qemu_get_byte(f);
1010
        n->nouni = qemu_get_byte(f);
1011
        n->nobcast = qemu_get_byte(f);
1012
    }
1013

    
1014
    if (version_id >= 11) {
1015
        if (qemu_get_byte(f) && !peer_has_ufo(n)) {
1016
            error_report("virtio-net: saved image requires TUN_F_UFO support");
1017
            return -1;
1018
        }
1019
    }
1020

    
1021
    /* Find the first multicast entry in the saved MAC filter */
1022
    for (i = 0; i < n->mac_table.in_use; i++) {
1023
        if (n->mac_table.macs[i * ETH_ALEN] & 1) {
1024
            break;
1025
        }
1026
    }
1027
    n->mac_table.first_multi = i;
1028

    
1029
    /* nc.link_down can't be migrated, so infer link_down according
1030
     * to link status bit in n->status */
1031
    qemu_get_queue(n->nic)->link_down = (n->status & VIRTIO_NET_S_LINK_UP) == 0;
1032

    
1033
    return 0;
1034
}
1035

    
1036
static void virtio_net_cleanup(NetClientState *nc)
1037
{
1038
    VirtIONet *n = qemu_get_nic_opaque(nc);
1039

    
1040
    n->nic = NULL;
1041
}
1042

    
1043
static NetClientInfo net_virtio_info = {
1044
    .type = NET_CLIENT_OPTIONS_KIND_NIC,
1045
    .size = sizeof(NICState),
1046
    .can_receive = virtio_net_can_receive,
1047
    .receive = virtio_net_receive,
1048
        .cleanup = virtio_net_cleanup,
1049
    .link_status_changed = virtio_net_set_link_status,
1050
};
1051

    
1052
static bool virtio_net_guest_notifier_pending(VirtIODevice *vdev, int idx)
1053
{
1054
    VirtIONet *n = to_virtio_net(vdev);
1055
    NetClientState *nc = qemu_get_queue(n->nic);
1056
    assert(n->vhost_started);
1057
    return vhost_net_virtqueue_pending(tap_get_vhost_net(nc->peer), idx);
1058
}
1059

    
1060
static void virtio_net_guest_notifier_mask(VirtIODevice *vdev, int idx,
1061
                                           bool mask)
1062
{
1063
    VirtIONet *n = to_virtio_net(vdev);
1064
    NetClientState *nc = qemu_get_queue(n->nic);
1065
    assert(n->vhost_started);
1066
    vhost_net_virtqueue_mask(tap_get_vhost_net(nc->peer),
1067
                             vdev, idx, mask);
1068
}
1069

    
1070
VirtIODevice *virtio_net_init(DeviceState *dev, NICConf *conf,
1071
                              virtio_net_conf *net)
1072
{
1073
    VirtIONet *n;
1074

    
1075
    n = (VirtIONet *)virtio_common_init("virtio-net", VIRTIO_ID_NET,
1076
                                        sizeof(struct virtio_net_config),
1077
                                        sizeof(VirtIONet));
1078

    
1079
    n->vdev.get_config = virtio_net_get_config;
1080
    n->vdev.set_config = virtio_net_set_config;
1081
    n->vdev.get_features = virtio_net_get_features;
1082
    n->vdev.set_features = virtio_net_set_features;
1083
    n->vdev.bad_features = virtio_net_bad_features;
1084
    n->vdev.reset = virtio_net_reset;
1085
    n->vdev.set_status = virtio_net_set_status;
1086
    n->vdev.guest_notifier_mask = virtio_net_guest_notifier_mask;
1087
    n->vdev.guest_notifier_pending = virtio_net_guest_notifier_pending;
1088
    n->rx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_rx);
1089

    
1090
    if (net->tx && strcmp(net->tx, "timer") && strcmp(net->tx, "bh")) {
1091
        error_report("virtio-net: "
1092
                     "Unknown option tx=%s, valid options: \"timer\" \"bh\"",
1093
                     net->tx);
1094
        error_report("Defaulting to \"bh\"");
1095
    }
1096

    
1097
    if (net->tx && !strcmp(net->tx, "timer")) {
1098
        n->tx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_tx_timer);
1099
        n->tx_timer = qemu_new_timer_ns(vm_clock, virtio_net_tx_timer, n);
1100
        n->tx_timeout = net->txtimer;
1101
    } else {
1102
        n->tx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_tx_bh);
1103
        n->tx_bh = qemu_bh_new(virtio_net_tx_bh, n);
1104
    }
1105
    n->ctrl_vq = virtio_add_queue(&n->vdev, 64, virtio_net_handle_ctrl);
1106
    qemu_macaddr_default_if_unset(&conf->macaddr);
1107
    memcpy(&n->mac[0], &conf->macaddr, sizeof(n->mac));
1108
    n->status = VIRTIO_NET_S_LINK_UP;
1109

    
1110
    n->nic = qemu_new_nic(&net_virtio_info, conf, object_get_typename(OBJECT(dev)), dev->id, n);
1111
    peer_test_vnet_hdr(n);
1112
    if (peer_has_vnet_hdr(n)) {
1113
        tap_using_vnet_hdr(qemu_get_queue(n->nic)->peer, true);
1114
        n->host_hdr_len = sizeof(struct virtio_net_hdr);
1115
    } else {
1116
        n->host_hdr_len = 0;
1117
    }
1118

    
1119
    qemu_format_nic_info_str(qemu_get_queue(n->nic), conf->macaddr.a);
1120

    
1121
    n->tx_waiting = 0;
1122
    n->tx_burst = net->txburst;
1123
    virtio_net_set_mrg_rx_bufs(n, 0);
1124
    n->promisc = 1; /* for compatibility */
1125

    
1126
    n->mac_table.macs = g_malloc0(MAC_TABLE_ENTRIES * ETH_ALEN);
1127

    
1128
    n->vlans = g_malloc0(MAX_VLAN >> 3);
1129

    
1130
    n->qdev = dev;
1131
    register_savevm(dev, "virtio-net", -1, VIRTIO_NET_VM_VERSION,
1132
                    virtio_net_save, virtio_net_load, n);
1133

    
1134
    add_boot_device_path(conf->bootindex, dev, "/ethernet-phy@0");
1135

    
1136
    return &n->vdev;
1137
}
1138

    
1139
void virtio_net_exit(VirtIODevice *vdev)
1140
{
1141
    VirtIONet *n = DO_UPCAST(VirtIONet, vdev, vdev);
1142

    
1143
    /* This will stop vhost backend if appropriate. */
1144
    virtio_net_set_status(vdev, 0);
1145

    
1146
    qemu_purge_queued_packets(qemu_get_queue(n->nic));
1147

    
1148
    unregister_savevm(n->qdev, "virtio-net", n);
1149

    
1150
    g_free(n->mac_table.macs);
1151
    g_free(n->vlans);
1152

    
1153
    if (n->tx_timer) {
1154
        qemu_del_timer(n->tx_timer);
1155
        qemu_free_timer(n->tx_timer);
1156
    } else {
1157
        qemu_bh_delete(n->tx_bh);
1158
    }
1159

    
1160
    qemu_del_nic(n->nic);
1161
    virtio_cleanup(&n->vdev);
1162
}