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1
/*
2
 * Virtio Network Device
3
 *
4
 * 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 "virtio.h"
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#include "net.h"
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#include "qemu-timer.h"
17
#include "virtio-net.h"
18

    
19
#define VIRTIO_NET_VM_VERSION    6
20

    
21
#define MAC_TABLE_ENTRIES    32
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#define MAX_VLAN    (1 << 12)   /* Per 802.1Q definition */
23

    
24
typedef struct VirtIONet
25
{
26
    VirtIODevice vdev;
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    uint8_t mac[ETH_ALEN];
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    uint16_t status;
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    VirtQueue *rx_vq;
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    VirtQueue *tx_vq;
31
    VirtQueue *ctrl_vq;
32
    VLANClientState *vc;
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    QEMUTimer *tx_timer;
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    int tx_timer_active;
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    int mergeable_rx_bufs;
36
    int promisc;
37
    int allmulti;
38
    struct {
39
        int in_use;
40
        uint8_t *macs;
41
    } mac_table;
42
    uint32_t *vlans;
43
} VirtIONet;
44

    
45
/* TODO
46
 * - we could suppress RX interrupt if we were so inclined.
47
 */
48

    
49
static VirtIONet *to_virtio_net(VirtIODevice *vdev)
50
{
51
    return (VirtIONet *)vdev;
52
}
53

    
54
static void virtio_net_get_config(VirtIODevice *vdev, uint8_t *config)
55
{
56
    VirtIONet *n = to_virtio_net(vdev);
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    struct virtio_net_config netcfg;
58

    
59
    netcfg.status = n->status;
60
    memcpy(netcfg.mac, n->mac, ETH_ALEN);
61
    memcpy(config, &netcfg, sizeof(netcfg));
62
}
63

    
64
static void virtio_net_set_config(VirtIODevice *vdev, const uint8_t *config)
65
{
66
    VirtIONet *n = to_virtio_net(vdev);
67
    struct virtio_net_config netcfg;
68

    
69
    memcpy(&netcfg, config, sizeof(netcfg));
70

    
71
    if (memcmp(netcfg.mac, n->mac, ETH_ALEN)) {
72
        memcpy(n->mac, netcfg.mac, ETH_ALEN);
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        qemu_format_nic_info_str(n->vc, n->mac);
74
    }
75
}
76

    
77
static void virtio_net_set_link_status(VLANClientState *vc)
78
{
79
    VirtIONet *n = vc->opaque;
80
    uint16_t old_status = n->status;
81

    
82
    if (vc->link_down)
83
        n->status &= ~VIRTIO_NET_S_LINK_UP;
84
    else
85
        n->status |= VIRTIO_NET_S_LINK_UP;
86

    
87
    if (n->status != old_status)
88
        virtio_notify_config(&n->vdev);
89
}
90

    
91
static void virtio_net_reset(VirtIODevice *vdev)
92
{
93
    VirtIONet *n = to_virtio_net(vdev);
94

    
95
    /* Reset back to compatibility mode */
96
    n->promisc = 1;
97
    n->allmulti = 0;
98

    
99
    /* Flush any MAC and VLAN filter table state */
100
    n->mac_table.in_use = 0;
101
    memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
102
    memset(n->vlans, 0, MAX_VLAN >> 3);
103
}
104

    
105
static uint32_t virtio_net_get_features(VirtIODevice *vdev)
106
{
107
    uint32_t features = (1 << VIRTIO_NET_F_MAC) |
108
                        (1 << VIRTIO_NET_F_STATUS) |
109
                        (1 << VIRTIO_NET_F_CTRL_VQ) |
110
                        (1 << VIRTIO_NET_F_CTRL_RX) |
111
                        (1 << VIRTIO_NET_F_CTRL_VLAN);
112

    
113
    return features;
114
}
115

    
116
static uint32_t virtio_net_bad_features(VirtIODevice *vdev)
117
{
118
    uint32_t features = 0;
119

    
120
    /* Linux kernel 2.6.25.  It understood MAC (as everyone must),
121
     * but also these: */
122
    features |= (1 << VIRTIO_NET_F_MAC);
123
    features |= (1 << VIRTIO_NET_F_GUEST_CSUM);
124
    features |= (1 << VIRTIO_NET_F_GUEST_TSO4);
125
    features |= (1 << VIRTIO_NET_F_GUEST_TSO6);
126
    features |= (1 << VIRTIO_NET_F_GUEST_ECN);
127

    
128
    return features & virtio_net_get_features(vdev);
129
}
130

    
131
static void virtio_net_set_features(VirtIODevice *vdev, uint32_t features)
132
{
133
    VirtIONet *n = to_virtio_net(vdev);
134

    
135
    n->mergeable_rx_bufs = !!(features & (1 << VIRTIO_NET_F_MRG_RXBUF));
136
}
137

    
138
static int virtio_net_handle_rx_mode(VirtIONet *n, uint8_t cmd,
139
                                     VirtQueueElement *elem)
140
{
141
    uint8_t on;
142

    
143
    if (elem->out_num != 2 || elem->out_sg[1].iov_len != sizeof(on)) {
144
        fprintf(stderr, "virtio-net ctrl invalid rx mode command\n");
145
        exit(1);
146
    }
147

    
148
    on = ldub_p(elem->out_sg[1].iov_base);
149

    
150
    if (cmd == VIRTIO_NET_CTRL_RX_MODE_PROMISC)
151
        n->promisc = on;
152
    else if (cmd == VIRTIO_NET_CTRL_RX_MODE_ALLMULTI)
153
        n->allmulti = on;
154
    else
155
        return VIRTIO_NET_ERR;
156

    
157
    return VIRTIO_NET_OK;
158
}
159

    
160
static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd,
161
                                 VirtQueueElement *elem)
162
{
163
    struct virtio_net_ctrl_mac mac_data;
164

    
165
    if (cmd != VIRTIO_NET_CTRL_MAC_TABLE_SET || elem->out_num != 3 ||
166
        elem->out_sg[1].iov_len < sizeof(mac_data) ||
167
        elem->out_sg[2].iov_len < sizeof(mac_data))
168
        return VIRTIO_NET_ERR;
169

    
170
    n->mac_table.in_use = 0;
171
    memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
172

    
173
    mac_data.entries = ldl_le_p(elem->out_sg[1].iov_base);
174

    
175
    if (sizeof(mac_data.entries) +
176
        (mac_data.entries * ETH_ALEN) > elem->out_sg[1].iov_len)
177
        return VIRTIO_NET_ERR;
178

    
179
    if (mac_data.entries <= MAC_TABLE_ENTRIES) {
180
        memcpy(n->mac_table.macs, elem->out_sg[1].iov_base + sizeof(mac_data),
181
               mac_data.entries * ETH_ALEN);
182
        n->mac_table.in_use += mac_data.entries;
183
    } else {
184
        n->promisc = 1;
185
        return VIRTIO_NET_OK;
186
    }
187

    
188
    mac_data.entries = ldl_le_p(elem->out_sg[2].iov_base);
189

    
190
    if (sizeof(mac_data.entries) +
191
        (mac_data.entries * ETH_ALEN) > elem->out_sg[2].iov_len)
192
        return VIRTIO_NET_ERR;
193

    
194
    if (mac_data.entries) {
195
        if (n->mac_table.in_use + mac_data.entries <= MAC_TABLE_ENTRIES) {
196
            memcpy(n->mac_table.macs + (n->mac_table.in_use * ETH_ALEN),
197
                   elem->out_sg[2].iov_base + sizeof(mac_data),
198
                   mac_data.entries * ETH_ALEN);
199
            n->mac_table.in_use += mac_data.entries;
200
        } else
201
            n->allmulti = 1;
202
    }
203

    
204
    return VIRTIO_NET_OK;
205
}
206

    
207
static int virtio_net_handle_vlan_table(VirtIONet *n, uint8_t cmd,
208
                                        VirtQueueElement *elem)
209
{
210
    uint16_t vid;
211

    
212
    if (elem->out_num != 2 || elem->out_sg[1].iov_len != sizeof(vid)) {
213
        fprintf(stderr, "virtio-net ctrl invalid vlan command\n");
214
        return VIRTIO_NET_ERR;
215
    }
216

    
217
    vid = lduw_le_p(elem->out_sg[1].iov_base);
218

    
219
    if (vid >= MAX_VLAN)
220
        return VIRTIO_NET_ERR;
221

    
222
    if (cmd == VIRTIO_NET_CTRL_VLAN_ADD)
223
        n->vlans[vid >> 5] |= (1U << (vid & 0x1f));
224
    else if (cmd == VIRTIO_NET_CTRL_VLAN_DEL)
225
        n->vlans[vid >> 5] &= ~(1U << (vid & 0x1f));
226
    else
227
        return VIRTIO_NET_ERR;
228

    
229
    return VIRTIO_NET_OK;
230
}
231

    
232
static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
233
{
234
    VirtIONet *n = to_virtio_net(vdev);
235
    struct virtio_net_ctrl_hdr ctrl;
236
    virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
237
    VirtQueueElement elem;
238

    
239
    while (virtqueue_pop(vq, &elem)) {
240
        if ((elem.in_num < 1) || (elem.out_num < 1)) {
241
            fprintf(stderr, "virtio-net ctrl missing headers\n");
242
            exit(1);
243
        }
244

    
245
        if (elem.out_sg[0].iov_len < sizeof(ctrl) ||
246
            elem.in_sg[elem.in_num - 1].iov_len < sizeof(status)) {
247
            fprintf(stderr, "virtio-net ctrl header not in correct element\n");
248
            exit(1);
249
        }
250

    
251
        ctrl.class = ldub_p(elem.out_sg[0].iov_base);
252
        ctrl.cmd = ldub_p(elem.out_sg[0].iov_base + sizeof(ctrl.class));
253

    
254
        if (ctrl.class == VIRTIO_NET_CTRL_RX_MODE)
255
            status = virtio_net_handle_rx_mode(n, ctrl.cmd, &elem);
256
        else if (ctrl.class == VIRTIO_NET_CTRL_MAC)
257
            status = virtio_net_handle_mac(n, ctrl.cmd, &elem);
258
        else if (ctrl.class == VIRTIO_NET_CTRL_VLAN)
259
            status = virtio_net_handle_vlan_table(n, ctrl.cmd, &elem);
260

    
261
        stb_p(elem.in_sg[elem.in_num - 1].iov_base, status);
262

    
263
        virtqueue_push(vq, &elem, sizeof(status));
264
        virtio_notify(vdev, vq);
265
    }
266
}
267

    
268
/* RX */
269

    
270
static void virtio_net_handle_rx(VirtIODevice *vdev, VirtQueue *vq)
271
{
272
}
273

    
274
static int do_virtio_net_can_receive(VirtIONet *n, int bufsize)
275
{
276
    if (!virtio_queue_ready(n->rx_vq) ||
277
        !(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
278
        return 0;
279

    
280
    if (virtio_queue_empty(n->rx_vq) ||
281
        (n->mergeable_rx_bufs &&
282
         !virtqueue_avail_bytes(n->rx_vq, bufsize, 0))) {
283
        virtio_queue_set_notification(n->rx_vq, 1);
284
        return 0;
285
    }
286

    
287
    virtio_queue_set_notification(n->rx_vq, 0);
288
    return 1;
289
}
290

    
291
static int virtio_net_can_receive(void *opaque)
292
{
293
    VirtIONet *n = opaque;
294

    
295
    return do_virtio_net_can_receive(n, VIRTIO_NET_MAX_BUFSIZE);
296
}
297

    
298
static int iov_fill(struct iovec *iov, int iovcnt, const void *buf, int count)
299
{
300
    int offset, i;
301

    
302
    offset = i = 0;
303
    while (offset < count && i < iovcnt) {
304
        int len = MIN(iov[i].iov_len, count - offset);
305
        memcpy(iov[i].iov_base, buf + offset, len);
306
        offset += len;
307
        i++;
308
    }
309

    
310
    return offset;
311
}
312

    
313
static int receive_header(VirtIONet *n, struct iovec *iov, int iovcnt,
314
                          const void *buf, size_t size, size_t hdr_len)
315
{
316
    struct virtio_net_hdr *hdr = (struct virtio_net_hdr *)iov[0].iov_base;
317
    int offset = 0;
318

    
319
    hdr->flags = 0;
320
    hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
321

    
322
    /* We only ever receive a struct virtio_net_hdr from the tapfd,
323
     * but we may be passing along a larger header to the guest.
324
     */
325
    iov[0].iov_base += hdr_len;
326
    iov[0].iov_len  -= hdr_len;
327

    
328
    return offset;
329
}
330

    
331
static int receive_filter(VirtIONet *n, const uint8_t *buf, int size)
332
{
333
    static const uint8_t bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
334
    static const uint8_t vlan[] = {0x81, 0x00};
335
    uint8_t *ptr = (uint8_t *)buf;
336
    int i;
337

    
338
    if (n->promisc)
339
        return 1;
340

    
341
    if (!memcmp(&ptr[12], vlan, sizeof(vlan))) {
342
        int vid = be16_to_cpup((uint16_t *)(ptr + 14)) & 0xfff;
343
        if (!(n->vlans[vid >> 5] & (1U << (vid & 0x1f))))
344
            return 0;
345
    }
346

    
347
    if ((ptr[0] & 1) && n->allmulti)
348
        return 1;
349

    
350
    if (!memcmp(ptr, bcast, sizeof(bcast)))
351
        return 1;
352

    
353
    if (!memcmp(ptr, n->mac, ETH_ALEN))
354
        return 1;
355

    
356
    for (i = 0; i < n->mac_table.in_use; i++) {
357
        if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN))
358
            return 1;
359
    }
360

    
361
    return 0;
362
}
363

    
364
static void virtio_net_receive(void *opaque, const uint8_t *buf, size_t size)
365
{
366
    VirtIONet *n = opaque;
367
    struct virtio_net_hdr_mrg_rxbuf *mhdr = NULL;
368
    size_t hdr_len, offset, i;
369

    
370
    if (!do_virtio_net_can_receive(n, size))
371
        return;
372

    
373
    if (!receive_filter(n, buf, size))
374
        return;
375

    
376
    /* hdr_len refers to the header we supply to the guest */
377
    hdr_len = n->mergeable_rx_bufs ?
378
        sizeof(struct virtio_net_hdr_mrg_rxbuf) : sizeof(struct virtio_net_hdr);
379

    
380
    offset = i = 0;
381

    
382
    while (offset < size) {
383
        VirtQueueElement elem;
384
        int len, total;
385
        struct iovec sg[VIRTQUEUE_MAX_SIZE];
386

    
387
        len = total = 0;
388

    
389
        if ((i != 0 && !n->mergeable_rx_bufs) ||
390
            virtqueue_pop(n->rx_vq, &elem) == 0) {
391
            if (i == 0)
392
                return;
393
            fprintf(stderr, "virtio-net truncating packet\n");
394
            exit(1);
395
        }
396

    
397
        if (elem.in_num < 1) {
398
            fprintf(stderr, "virtio-net receive queue contains no in buffers\n");
399
            exit(1);
400
        }
401

    
402
        if (!n->mergeable_rx_bufs && elem.in_sg[0].iov_len != hdr_len) {
403
            fprintf(stderr, "virtio-net header not in first element\n");
404
            exit(1);
405
        }
406

    
407
        memcpy(&sg, &elem.in_sg[0], sizeof(sg[0]) * elem.in_num);
408

    
409
        if (i == 0) {
410
            if (n->mergeable_rx_bufs)
411
                mhdr = (struct virtio_net_hdr_mrg_rxbuf *)sg[0].iov_base;
412

    
413
            offset += receive_header(n, sg, elem.in_num,
414
                                     buf + offset, size - offset, hdr_len);
415
            total += hdr_len;
416
        }
417

    
418
        /* copy in packet.  ugh */
419
        len = iov_fill(sg, elem.in_num,
420
                       buf + offset, size - offset);
421
        total += len;
422

    
423
        /* signal other side */
424
        virtqueue_fill(n->rx_vq, &elem, total, i++);
425

    
426
        offset += len;
427
    }
428

    
429
    if (mhdr)
430
        mhdr->num_buffers = i;
431

    
432
    virtqueue_flush(n->rx_vq, i);
433
    virtio_notify(&n->vdev, n->rx_vq);
434
}
435

    
436
/* TX */
437
static void virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq)
438
{
439
    VirtQueueElement elem;
440
    int has_vnet_hdr = 0;
441

    
442
    if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
443
        return;
444

    
445
    while (virtqueue_pop(vq, &elem)) {
446
        ssize_t len = 0;
447
        unsigned int out_num = elem.out_num;
448
        struct iovec *out_sg = &elem.out_sg[0];
449
        unsigned hdr_len;
450

    
451
        /* hdr_len refers to the header received from the guest */
452
        hdr_len = n->mergeable_rx_bufs ?
453
            sizeof(struct virtio_net_hdr_mrg_rxbuf) :
454
            sizeof(struct virtio_net_hdr);
455

    
456
        if (out_num < 1 || out_sg->iov_len != hdr_len) {
457
            fprintf(stderr, "virtio-net header not in first element\n");
458
            exit(1);
459
        }
460

    
461
        /* ignore the header if GSO is not supported */
462
        if (!has_vnet_hdr) {
463
            out_num--;
464
            out_sg++;
465
            len += hdr_len;
466
        } else if (n->mergeable_rx_bufs) {
467
            /* tapfd expects a struct virtio_net_hdr */
468
            hdr_len -= sizeof(struct virtio_net_hdr);
469
            out_sg->iov_len -= hdr_len;
470
            len += hdr_len;
471
        }
472

    
473
        len += qemu_sendv_packet(n->vc, out_sg, out_num);
474

    
475
        virtqueue_push(vq, &elem, len);
476
        virtio_notify(&n->vdev, vq);
477
    }
478
}
479

    
480
static void virtio_net_handle_tx(VirtIODevice *vdev, VirtQueue *vq)
481
{
482
    VirtIONet *n = to_virtio_net(vdev);
483

    
484
    if (n->tx_timer_active) {
485
        virtio_queue_set_notification(vq, 1);
486
        qemu_del_timer(n->tx_timer);
487
        n->tx_timer_active = 0;
488
        virtio_net_flush_tx(n, vq);
489
    } else {
490
        qemu_mod_timer(n->tx_timer,
491
                       qemu_get_clock(vm_clock) + TX_TIMER_INTERVAL);
492
        n->tx_timer_active = 1;
493
        virtio_queue_set_notification(vq, 0);
494
    }
495
}
496

    
497
static void virtio_net_tx_timer(void *opaque)
498
{
499
    VirtIONet *n = opaque;
500

    
501
    n->tx_timer_active = 0;
502

    
503
    /* Just in case the driver is not ready on more */
504
    if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
505
        return;
506

    
507
    virtio_queue_set_notification(n->tx_vq, 1);
508
    virtio_net_flush_tx(n, n->tx_vq);
509
}
510

    
511
static void virtio_net_save(QEMUFile *f, void *opaque)
512
{
513
    VirtIONet *n = opaque;
514

    
515
    virtio_save(&n->vdev, f);
516

    
517
    qemu_put_buffer(f, n->mac, ETH_ALEN);
518
    qemu_put_be32(f, n->tx_timer_active);
519
    qemu_put_be32(f, n->mergeable_rx_bufs);
520
    qemu_put_be16(f, n->status);
521
    qemu_put_be32(f, n->promisc);
522
    qemu_put_be32(f, n->allmulti);
523
    qemu_put_be32(f, n->mac_table.in_use);
524
    qemu_put_buffer(f, n->mac_table.macs, n->mac_table.in_use * ETH_ALEN);
525
    qemu_put_buffer(f, (uint8_t *)n->vlans, MAX_VLAN >> 3);
526
}
527

    
528
static int virtio_net_load(QEMUFile *f, void *opaque, int version_id)
529
{
530
    VirtIONet *n = opaque;
531

    
532
    if (version_id < 2 || version_id > VIRTIO_NET_VM_VERSION)
533
        return -EINVAL;
534

    
535
    virtio_load(&n->vdev, f);
536

    
537
    qemu_get_buffer(f, n->mac, ETH_ALEN);
538
    n->tx_timer_active = qemu_get_be32(f);
539
    n->mergeable_rx_bufs = qemu_get_be32(f);
540

    
541
    if (version_id >= 3)
542
        n->status = qemu_get_be16(f);
543

    
544
    if (version_id >= 4) {
545
        n->promisc = qemu_get_be32(f);
546
        n->allmulti = qemu_get_be32(f);
547
    }
548

    
549
    if (version_id >= 5) {
550
        n->mac_table.in_use = qemu_get_be32(f);
551
        /* MAC_TABLE_ENTRIES may be different from the saved image */
552
        if (n->mac_table.in_use <= MAC_TABLE_ENTRIES) {
553
            qemu_get_buffer(f, n->mac_table.macs,
554
                            n->mac_table.in_use * ETH_ALEN);
555
        } else if (n->mac_table.in_use) {
556
            qemu_fseek(f, n->mac_table.in_use * ETH_ALEN, SEEK_CUR);
557
            n->promisc = 1;
558
            n->mac_table.in_use = 0;
559
        }
560
    }
561
 
562
    if (version_id >= 6)
563
        qemu_get_buffer(f, (uint8_t *)n->vlans, MAX_VLAN >> 3);
564

    
565
    if (n->tx_timer_active) {
566
        qemu_mod_timer(n->tx_timer,
567
                       qemu_get_clock(vm_clock) + TX_TIMER_INTERVAL);
568
    }
569

    
570
    return 0;
571
}
572

    
573
static void virtio_net_cleanup(VLANClientState *vc)
574
{
575
    VirtIONet *n = vc->opaque;
576

    
577
    unregister_savevm("virtio-net", n);
578

    
579
    qemu_free(n->mac_table.macs);
580
    qemu_free(n->vlans);
581

    
582
    qemu_del_timer(n->tx_timer);
583
    qemu_free_timer(n->tx_timer);
584

    
585
    virtio_cleanup(&n->vdev);
586
}
587

    
588
VirtIODevice *virtio_net_init(DeviceState *dev)
589
{
590
    VirtIONet *n;
591
    static int virtio_net_id;
592

    
593
    n = (VirtIONet *)virtio_common_init("virtio-net", VIRTIO_ID_NET,
594
                                        sizeof(struct virtio_net_config),
595
                                        sizeof(VirtIONet));
596

    
597
    n->vdev.get_config = virtio_net_get_config;
598
    n->vdev.set_config = virtio_net_set_config;
599
    n->vdev.get_features = virtio_net_get_features;
600
    n->vdev.set_features = virtio_net_set_features;
601
    n->vdev.bad_features = virtio_net_bad_features;
602
    n->vdev.reset = virtio_net_reset;
603
    n->rx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_rx);
604
    n->tx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_tx);
605
    n->ctrl_vq = virtio_add_queue(&n->vdev, 16, virtio_net_handle_ctrl);
606
    qdev_get_macaddr(dev, n->mac);
607
    n->status = VIRTIO_NET_S_LINK_UP;
608
    n->vc = qdev_get_vlan_client(dev,
609
                                 virtio_net_can_receive,
610
                                 virtio_net_receive, NULL,
611
                                 virtio_net_cleanup, n);
612
    n->vc->link_status_changed = virtio_net_set_link_status;
613

    
614
    qemu_format_nic_info_str(n->vc, n->mac);
615

    
616
    n->tx_timer = qemu_new_timer(vm_clock, virtio_net_tx_timer, n);
617
    n->tx_timer_active = 0;
618
    n->mergeable_rx_bufs = 0;
619
    n->promisc = 1; /* for compatibility */
620

    
621
    n->mac_table.macs = qemu_mallocz(MAC_TABLE_ENTRIES * ETH_ALEN);
622

    
623
    n->vlans = qemu_mallocz(MAX_VLAN >> 3);
624

    
625
    register_savevm("virtio-net", virtio_net_id++, VIRTIO_NET_VM_VERSION,
626
                    virtio_net_save, virtio_net_load, n);
627

    
628
    return &n->vdev;
629
}