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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
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 * the COPYING file in the top-level directory.
11
 *
12
 */
13

    
14
#include "virtio.h"
15
#include "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.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"
22

    
23
#define VIRTIO_NET_VM_VERSION    11
24

    
25
#define MAC_TABLE_ENTRIES    64
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#define MAX_VLAN    (1 << 12)   /* Per 802.1Q definition */
27

    
28
typedef struct VirtIONet
29
{
30
    VirtIODevice vdev;
31
    uint8_t mac[ETH_ALEN];
32
    uint16_t status;
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    VirtQueue *rx_vq;
34
    VirtQueue *tx_vq;
35
    VirtQueue *ctrl_vq;
36
    NICState *nic;
37
    QEMUTimer *tx_timer;
38
    int tx_timer_active;
39
    uint32_t has_vnet_hdr;
40
    uint8_t has_ufo;
41
    struct {
42
        VirtQueueElement elem;
43
        ssize_t len;
44
    } async_tx;
45
    int mergeable_rx_bufs;
46
    uint8_t promisc;
47
    uint8_t allmulti;
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    uint8_t alluni;
49
    uint8_t nomulti;
50
    uint8_t nouni;
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    uint8_t nobcast;
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    uint8_t vhost_started;
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    VMChangeStateEntry *vmstate;
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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;
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    } mac_table;
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    uint32_t *vlans;
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} VirtIONet;
63

    
64
/* TODO
65
 * - we could suppress RX interrupt if we were so inclined.
66
 */
67

    
68
static VirtIONet *to_virtio_net(VirtIODevice *vdev)
69
{
70
    return (VirtIONet *)vdev;
71
}
72

    
73
static void virtio_net_get_config(VirtIODevice *vdev, uint8_t *config)
74
{
75
    VirtIONet *n = to_virtio_net(vdev);
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    struct virtio_net_config netcfg;
77

    
78
    netcfg.status = n->status;
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    memcpy(netcfg.mac, n->mac, ETH_ALEN);
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    memcpy(config, &netcfg, sizeof(netcfg));
81
}
82

    
83
static void virtio_net_set_config(VirtIODevice *vdev, const uint8_t *config)
84
{
85
    VirtIONet *n = to_virtio_net(vdev);
86
    struct virtio_net_config netcfg;
87

    
88
    memcpy(&netcfg, config, sizeof(netcfg));
89

    
90
    if (memcmp(netcfg.mac, n->mac, ETH_ALEN)) {
91
        memcpy(n->mac, netcfg.mac, ETH_ALEN);
92
        qemu_format_nic_info_str(&n->nic->nc, n->mac);
93
    }
94
}
95

    
96
static void virtio_net_set_link_status(VLANClientState *nc)
97
{
98
    VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
99
    uint16_t old_status = n->status;
100

    
101
    if (nc->link_down)
102
        n->status &= ~VIRTIO_NET_S_LINK_UP;
103
    else
104
        n->status |= VIRTIO_NET_S_LINK_UP;
105

    
106
    if (n->status != old_status)
107
        virtio_notify_config(&n->vdev);
108
}
109

    
110
static void virtio_net_reset(VirtIODevice *vdev)
111
{
112
    VirtIONet *n = to_virtio_net(vdev);
113

    
114
    /* Reset back to compatibility mode */
115
    n->promisc = 1;
116
    n->allmulti = 0;
117
    n->alluni = 0;
118
    n->nomulti = 0;
119
    n->nouni = 0;
120
    n->nobcast = 0;
121
    if (n->vhost_started) {
122
        vhost_net_stop(tap_get_vhost_net(n->nic->nc.peer), vdev);
123
        n->vhost_started = 0;
124
    }
125

    
126
    /* Flush any MAC and VLAN filter table state */
127
    n->mac_table.in_use = 0;
128
    n->mac_table.first_multi = 0;
129
    n->mac_table.multi_overflow = 0;
130
    n->mac_table.uni_overflow = 0;
131
    memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
132
    memset(n->vlans, 0, MAX_VLAN >> 3);
133
}
134

    
135
static int peer_has_vnet_hdr(VirtIONet *n)
136
{
137
    if (!n->nic->nc.peer)
138
        return 0;
139

    
140
    if (n->nic->nc.peer->info->type != NET_CLIENT_TYPE_TAP)
141
        return 0;
142

    
143
    n->has_vnet_hdr = tap_has_vnet_hdr(n->nic->nc.peer);
144

    
145
    return n->has_vnet_hdr;
146
}
147

    
148
static int peer_has_ufo(VirtIONet *n)
149
{
150
    if (!peer_has_vnet_hdr(n))
151
        return 0;
152

    
153
    n->has_ufo = tap_has_ufo(n->nic->nc.peer);
154

    
155
    return n->has_ufo;
156
}
157

    
158
static uint32_t virtio_net_get_features(VirtIODevice *vdev, uint32_t features)
159
{
160
    VirtIONet *n = to_virtio_net(vdev);
161

    
162
    features |= (1 << VIRTIO_NET_F_MAC);
163

    
164
    if (peer_has_vnet_hdr(n)) {
165
        tap_using_vnet_hdr(n->nic->nc.peer, 1);
166
    } else {
167
        features &= ~(0x1 << VIRTIO_NET_F_CSUM);
168
        features &= ~(0x1 << VIRTIO_NET_F_HOST_TSO4);
169
        features &= ~(0x1 << VIRTIO_NET_F_HOST_TSO6);
170
        features &= ~(0x1 << VIRTIO_NET_F_HOST_ECN);
171

    
172
        features &= ~(0x1 << VIRTIO_NET_F_GUEST_CSUM);
173
        features &= ~(0x1 << VIRTIO_NET_F_GUEST_TSO4);
174
        features &= ~(0x1 << VIRTIO_NET_F_GUEST_TSO6);
175
        features &= ~(0x1 << VIRTIO_NET_F_GUEST_ECN);
176
    }
177

    
178
    if (!peer_has_vnet_hdr(n) || !peer_has_ufo(n)) {
179
        features &= ~(0x1 << VIRTIO_NET_F_GUEST_UFO);
180
        features &= ~(0x1 << VIRTIO_NET_F_HOST_UFO);
181
    }
182

    
183
    if (!n->nic->nc.peer ||
184
        n->nic->nc.peer->info->type != NET_CLIENT_TYPE_TAP) {
185
        return features;
186
    }
187
    if (!tap_get_vhost_net(n->nic->nc.peer)) {
188
        return features;
189
    }
190
    return vhost_net_get_features(tap_get_vhost_net(n->nic->nc.peer), features);
191
}
192

    
193
static uint32_t virtio_net_bad_features(VirtIODevice *vdev)
194
{
195
    uint32_t features = 0;
196

    
197
    /* Linux kernel 2.6.25.  It understood MAC (as everyone must),
198
     * but also these: */
199
    features |= (1 << VIRTIO_NET_F_MAC);
200
    features |= (1 << VIRTIO_NET_F_CSUM);
201
    features |= (1 << VIRTIO_NET_F_HOST_TSO4);
202
    features |= (1 << VIRTIO_NET_F_HOST_TSO6);
203
    features |= (1 << VIRTIO_NET_F_HOST_ECN);
204

    
205
    return features;
206
}
207

    
208
static void virtio_net_set_features(VirtIODevice *vdev, uint32_t features)
209
{
210
    VirtIONet *n = to_virtio_net(vdev);
211

    
212
    n->mergeable_rx_bufs = !!(features & (1 << VIRTIO_NET_F_MRG_RXBUF));
213

    
214
    if (n->has_vnet_hdr) {
215
        tap_set_offload(n->nic->nc.peer,
216
                        (features >> VIRTIO_NET_F_GUEST_CSUM) & 1,
217
                        (features >> VIRTIO_NET_F_GUEST_TSO4) & 1,
218
                        (features >> VIRTIO_NET_F_GUEST_TSO6) & 1,
219
                        (features >> VIRTIO_NET_F_GUEST_ECN)  & 1,
220
                        (features >> VIRTIO_NET_F_GUEST_UFO)  & 1);
221
    }
222
}
223

    
224
static int virtio_net_handle_rx_mode(VirtIONet *n, uint8_t cmd,
225
                                     VirtQueueElement *elem)
226
{
227
    uint8_t on;
228

    
229
    if (elem->out_num != 2 || elem->out_sg[1].iov_len != sizeof(on)) {
230
        fprintf(stderr, "virtio-net ctrl invalid rx mode command\n");
231
        exit(1);
232
    }
233

    
234
    on = ldub_p(elem->out_sg[1].iov_base);
235

    
236
    if (cmd == VIRTIO_NET_CTRL_RX_MODE_PROMISC)
237
        n->promisc = on;
238
    else if (cmd == VIRTIO_NET_CTRL_RX_MODE_ALLMULTI)
239
        n->allmulti = on;
240
    else if (cmd == VIRTIO_NET_CTRL_RX_MODE_ALLUNI)
241
        n->alluni = on;
242
    else if (cmd == VIRTIO_NET_CTRL_RX_MODE_NOMULTI)
243
        n->nomulti = on;
244
    else if (cmd == VIRTIO_NET_CTRL_RX_MODE_NOUNI)
245
        n->nouni = on;
246
    else if (cmd == VIRTIO_NET_CTRL_RX_MODE_NOBCAST)
247
        n->nobcast = on;
248
    else
249
        return VIRTIO_NET_ERR;
250

    
251
    return VIRTIO_NET_OK;
252
}
253

    
254
static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd,
255
                                 VirtQueueElement *elem)
256
{
257
    struct virtio_net_ctrl_mac mac_data;
258

    
259
    if (cmd != VIRTIO_NET_CTRL_MAC_TABLE_SET || elem->out_num != 3 ||
260
        elem->out_sg[1].iov_len < sizeof(mac_data) ||
261
        elem->out_sg[2].iov_len < sizeof(mac_data))
262
        return VIRTIO_NET_ERR;
263

    
264
    n->mac_table.in_use = 0;
265
    n->mac_table.first_multi = 0;
266
    n->mac_table.uni_overflow = 0;
267
    n->mac_table.multi_overflow = 0;
268
    memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
269

    
270
    mac_data.entries = ldl_le_p(elem->out_sg[1].iov_base);
271

    
272
    if (sizeof(mac_data.entries) +
273
        (mac_data.entries * ETH_ALEN) > elem->out_sg[1].iov_len)
274
        return VIRTIO_NET_ERR;
275

    
276
    if (mac_data.entries <= MAC_TABLE_ENTRIES) {
277
        memcpy(n->mac_table.macs, elem->out_sg[1].iov_base + sizeof(mac_data),
278
               mac_data.entries * ETH_ALEN);
279
        n->mac_table.in_use += mac_data.entries;
280
    } else {
281
        n->mac_table.uni_overflow = 1;
282
    }
283

    
284
    n->mac_table.first_multi = n->mac_table.in_use;
285

    
286
    mac_data.entries = ldl_le_p(elem->out_sg[2].iov_base);
287

    
288
    if (sizeof(mac_data.entries) +
289
        (mac_data.entries * ETH_ALEN) > elem->out_sg[2].iov_len)
290
        return VIRTIO_NET_ERR;
291

    
292
    if (mac_data.entries) {
293
        if (n->mac_table.in_use + mac_data.entries <= MAC_TABLE_ENTRIES) {
294
            memcpy(n->mac_table.macs + (n->mac_table.in_use * ETH_ALEN),
295
                   elem->out_sg[2].iov_base + sizeof(mac_data),
296
                   mac_data.entries * ETH_ALEN);
297
            n->mac_table.in_use += mac_data.entries;
298
        } else {
299
            n->mac_table.multi_overflow = 1;
300
        }
301
    }
302

    
303
    return VIRTIO_NET_OK;
304
}
305

    
306
static int virtio_net_handle_vlan_table(VirtIONet *n, uint8_t cmd,
307
                                        VirtQueueElement *elem)
308
{
309
    uint16_t vid;
310

    
311
    if (elem->out_num != 2 || elem->out_sg[1].iov_len != sizeof(vid)) {
312
        fprintf(stderr, "virtio-net ctrl invalid vlan command\n");
313
        return VIRTIO_NET_ERR;
314
    }
315

    
316
    vid = lduw_le_p(elem->out_sg[1].iov_base);
317

    
318
    if (vid >= MAX_VLAN)
319
        return VIRTIO_NET_ERR;
320

    
321
    if (cmd == VIRTIO_NET_CTRL_VLAN_ADD)
322
        n->vlans[vid >> 5] |= (1U << (vid & 0x1f));
323
    else if (cmd == VIRTIO_NET_CTRL_VLAN_DEL)
324
        n->vlans[vid >> 5] &= ~(1U << (vid & 0x1f));
325
    else
326
        return VIRTIO_NET_ERR;
327

    
328
    return VIRTIO_NET_OK;
329
}
330

    
331
static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
332
{
333
    VirtIONet *n = to_virtio_net(vdev);
334
    struct virtio_net_ctrl_hdr ctrl;
335
    virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
336
    VirtQueueElement elem;
337

    
338
    while (virtqueue_pop(vq, &elem)) {
339
        if ((elem.in_num < 1) || (elem.out_num < 1)) {
340
            fprintf(stderr, "virtio-net ctrl missing headers\n");
341
            exit(1);
342
        }
343

    
344
        if (elem.out_sg[0].iov_len < sizeof(ctrl) ||
345
            elem.in_sg[elem.in_num - 1].iov_len < sizeof(status)) {
346
            fprintf(stderr, "virtio-net ctrl header not in correct element\n");
347
            exit(1);
348
        }
349

    
350
        ctrl.class = ldub_p(elem.out_sg[0].iov_base);
351
        ctrl.cmd = ldub_p(elem.out_sg[0].iov_base + sizeof(ctrl.class));
352

    
353
        if (ctrl.class == VIRTIO_NET_CTRL_RX_MODE)
354
            status = virtio_net_handle_rx_mode(n, ctrl.cmd, &elem);
355
        else if (ctrl.class == VIRTIO_NET_CTRL_MAC)
356
            status = virtio_net_handle_mac(n, ctrl.cmd, &elem);
357
        else if (ctrl.class == VIRTIO_NET_CTRL_VLAN)
358
            status = virtio_net_handle_vlan_table(n, ctrl.cmd, &elem);
359

    
360
        stb_p(elem.in_sg[elem.in_num - 1].iov_base, status);
361

    
362
        virtqueue_push(vq, &elem, sizeof(status));
363
        virtio_notify(vdev, vq);
364
    }
365
}
366

    
367
/* RX */
368

    
369
static void virtio_net_handle_rx(VirtIODevice *vdev, VirtQueue *vq)
370
{
371
    VirtIONet *n = to_virtio_net(vdev);
372

    
373
    qemu_flush_queued_packets(&n->nic->nc);
374

    
375
    /* We now have RX buffers, signal to the IO thread to break out of the
376
     * select to re-poll the tap file descriptor */
377
    qemu_notify_event();
378
}
379

    
380
static int virtio_net_can_receive(VLANClientState *nc)
381
{
382
    VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
383

    
384
    if (!virtio_queue_ready(n->rx_vq) ||
385
        !(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
386
        return 0;
387

    
388
    return 1;
389
}
390

    
391
static int virtio_net_has_buffers(VirtIONet *n, int bufsize)
392
{
393
    if (virtio_queue_empty(n->rx_vq) ||
394
        (n->mergeable_rx_bufs &&
395
         !virtqueue_avail_bytes(n->rx_vq, bufsize, 0))) {
396
        virtio_queue_set_notification(n->rx_vq, 1);
397

    
398
        /* To avoid a race condition where the guest has made some buffers
399
         * available after the above check but before notification was
400
         * enabled, check for available buffers again.
401
         */
402
        if (virtio_queue_empty(n->rx_vq) ||
403
            (n->mergeable_rx_bufs &&
404
             !virtqueue_avail_bytes(n->rx_vq, bufsize, 0)))
405
            return 0;
406
    }
407

    
408
    virtio_queue_set_notification(n->rx_vq, 0);
409
    return 1;
410
}
411

    
412
/* dhclient uses AF_PACKET but doesn't pass auxdata to the kernel so
413
 * it never finds out that the packets don't have valid checksums.  This
414
 * causes dhclient to get upset.  Fedora's carried a patch for ages to
415
 * fix this with Xen but it hasn't appeared in an upstream release of
416
 * dhclient yet.
417
 *
418
 * To avoid breaking existing guests, we catch udp packets and add
419
 * checksums.  This is terrible but it's better than hacking the guest
420
 * kernels.
421
 *
422
 * N.B. if we introduce a zero-copy API, this operation is no longer free so
423
 * we should provide a mechanism to disable it to avoid polluting the host
424
 * cache.
425
 */
426
static void work_around_broken_dhclient(struct virtio_net_hdr *hdr,
427
                                        const uint8_t *buf, size_t size)
428
{
429
    if ((hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && /* missing csum */
430
        (size > 27 && size < 1500) && /* normal sized MTU */
431
        (buf[12] == 0x08 && buf[13] == 0x00) && /* ethertype == IPv4 */
432
        (buf[23] == 17) && /* ip.protocol == UDP */
433
        (buf[34] == 0 && buf[35] == 67)) { /* udp.srcport == bootps */
434
        /* FIXME this cast is evil */
435
        net_checksum_calculate((uint8_t *)buf, size);
436
        hdr->flags &= ~VIRTIO_NET_HDR_F_NEEDS_CSUM;
437
    }
438
}
439

    
440
static int iov_fill(struct iovec *iov, int iovcnt, const void *buf, int count)
441
{
442
    int offset, i;
443

    
444
    offset = i = 0;
445
    while (offset < count && i < iovcnt) {
446
        int len = MIN(iov[i].iov_len, count - offset);
447
        memcpy(iov[i].iov_base, buf + offset, len);
448
        offset += len;
449
        i++;
450
    }
451

    
452
    return offset;
453
}
454

    
455
static int receive_header(VirtIONet *n, struct iovec *iov, int iovcnt,
456
                          const void *buf, size_t size, size_t hdr_len)
457
{
458
    struct virtio_net_hdr *hdr = (struct virtio_net_hdr *)iov[0].iov_base;
459
    int offset = 0;
460

    
461
    hdr->flags = 0;
462
    hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
463

    
464
    if (n->has_vnet_hdr) {
465
        memcpy(hdr, buf, sizeof(*hdr));
466
        offset = sizeof(*hdr);
467
        work_around_broken_dhclient(hdr, buf + offset, size - offset);
468
    }
469

    
470
    /* We only ever receive a struct virtio_net_hdr from the tapfd,
471
     * but we may be passing along a larger header to the guest.
472
     */
473
    iov[0].iov_base += hdr_len;
474
    iov[0].iov_len  -= hdr_len;
475

    
476
    return offset;
477
}
478

    
479
static int receive_filter(VirtIONet *n, const uint8_t *buf, int size)
480
{
481
    static const uint8_t bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
482
    static const uint8_t vlan[] = {0x81, 0x00};
483
    uint8_t *ptr = (uint8_t *)buf;
484
    int i;
485

    
486
    if (n->promisc)
487
        return 1;
488

    
489
    if (n->has_vnet_hdr) {
490
        ptr += sizeof(struct virtio_net_hdr);
491
    }
492

    
493
    if (!memcmp(&ptr[12], vlan, sizeof(vlan))) {
494
        int vid = be16_to_cpup((uint16_t *)(ptr + 14)) & 0xfff;
495
        if (!(n->vlans[vid >> 5] & (1U << (vid & 0x1f))))
496
            return 0;
497
    }
498

    
499
    if (ptr[0] & 1) { // multicast
500
        if (!memcmp(ptr, bcast, sizeof(bcast))) {
501
            return !n->nobcast;
502
        } else if (n->nomulti) {
503
            return 0;
504
        } else if (n->allmulti || n->mac_table.multi_overflow) {
505
            return 1;
506
        }
507

    
508
        for (i = n->mac_table.first_multi; i < n->mac_table.in_use; i++) {
509
            if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN)) {
510
                return 1;
511
            }
512
        }
513
    } else { // unicast
514
        if (n->nouni) {
515
            return 0;
516
        } else if (n->alluni || n->mac_table.uni_overflow) {
517
            return 1;
518
        } else if (!memcmp(ptr, n->mac, ETH_ALEN)) {
519
            return 1;
520
        }
521

    
522
        for (i = 0; i < n->mac_table.first_multi; i++) {
523
            if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN)) {
524
                return 1;
525
            }
526
        }
527
    }
528

    
529
    return 0;
530
}
531

    
532
static ssize_t virtio_net_receive(VLANClientState *nc, const uint8_t *buf, size_t size)
533
{
534
    VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
535
    struct virtio_net_hdr_mrg_rxbuf *mhdr = NULL;
536
    size_t hdr_len, offset, i;
537

    
538
    if (!virtio_net_can_receive(&n->nic->nc))
539
        return -1;
540

    
541
    if (!virtio_net_has_buffers(n, size))
542
        return 0;
543

    
544
    if (!receive_filter(n, buf, size))
545
        return size;
546

    
547
    /* hdr_len refers to the header we supply to the guest */
548
    hdr_len = n->mergeable_rx_bufs ?
549
        sizeof(struct virtio_net_hdr_mrg_rxbuf) : sizeof(struct virtio_net_hdr);
550

    
551
    offset = i = 0;
552

    
553
    while (offset < size) {
554
        VirtQueueElement elem;
555
        int len, total;
556
        struct iovec sg[VIRTQUEUE_MAX_SIZE];
557

    
558
        total = 0;
559

    
560
        if ((i != 0 && !n->mergeable_rx_bufs) ||
561
            virtqueue_pop(n->rx_vq, &elem) == 0) {
562
            if (i == 0)
563
                return -1;
564
            fprintf(stderr, "virtio-net truncating packet\n");
565
            exit(1);
566
        }
567

    
568
        if (elem.in_num < 1) {
569
            fprintf(stderr, "virtio-net receive queue contains no in buffers\n");
570
            exit(1);
571
        }
572

    
573
        if (!n->mergeable_rx_bufs && elem.in_sg[0].iov_len != hdr_len) {
574
            fprintf(stderr, "virtio-net header not in first element\n");
575
            exit(1);
576
        }
577

    
578
        memcpy(&sg, &elem.in_sg[0], sizeof(sg[0]) * elem.in_num);
579

    
580
        if (i == 0) {
581
            if (n->mergeable_rx_bufs)
582
                mhdr = (struct virtio_net_hdr_mrg_rxbuf *)sg[0].iov_base;
583

    
584
            offset += receive_header(n, sg, elem.in_num,
585
                                     buf + offset, size - offset, hdr_len);
586
            total += hdr_len;
587
        }
588

    
589
        /* copy in packet.  ugh */
590
        len = iov_fill(sg, elem.in_num,
591
                       buf + offset, size - offset);
592
        total += len;
593

    
594
        /* signal other side */
595
        virtqueue_fill(n->rx_vq, &elem, total, i++);
596

    
597
        offset += len;
598
    }
599

    
600
    if (mhdr)
601
        mhdr->num_buffers = i;
602

    
603
    virtqueue_flush(n->rx_vq, i);
604
    virtio_notify(&n->vdev, n->rx_vq);
605

    
606
    return size;
607
}
608

    
609
static void virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq);
610

    
611
static void virtio_net_tx_complete(VLANClientState *nc, ssize_t len)
612
{
613
    VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
614

    
615
    virtqueue_push(n->tx_vq, &n->async_tx.elem, n->async_tx.len);
616
    virtio_notify(&n->vdev, n->tx_vq);
617

    
618
    n->async_tx.elem.out_num = n->async_tx.len = 0;
619

    
620
    virtio_queue_set_notification(n->tx_vq, 1);
621
    virtio_net_flush_tx(n, n->tx_vq);
622
}
623

    
624
/* TX */
625
static void virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq)
626
{
627
    VirtQueueElement elem;
628

    
629
    if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
630
        return;
631

    
632
    if (n->async_tx.elem.out_num) {
633
        virtio_queue_set_notification(n->tx_vq, 0);
634
        return;
635
    }
636

    
637
    while (virtqueue_pop(vq, &elem)) {
638
        ssize_t ret, len = 0;
639
        unsigned int out_num = elem.out_num;
640
        struct iovec *out_sg = &elem.out_sg[0];
641
        unsigned hdr_len;
642

    
643
        /* hdr_len refers to the header received from the guest */
644
        hdr_len = n->mergeable_rx_bufs ?
645
            sizeof(struct virtio_net_hdr_mrg_rxbuf) :
646
            sizeof(struct virtio_net_hdr);
647

    
648
        if (out_num < 1 || out_sg->iov_len != hdr_len) {
649
            fprintf(stderr, "virtio-net header not in first element\n");
650
            exit(1);
651
        }
652

    
653
        /* ignore the header if GSO is not supported */
654
        if (!n->has_vnet_hdr) {
655
            out_num--;
656
            out_sg++;
657
            len += hdr_len;
658
        } else if (n->mergeable_rx_bufs) {
659
            /* tapfd expects a struct virtio_net_hdr */
660
            hdr_len -= sizeof(struct virtio_net_hdr);
661
            out_sg->iov_len -= hdr_len;
662
            len += hdr_len;
663
        }
664

    
665
        ret = qemu_sendv_packet_async(&n->nic->nc, out_sg, out_num,
666
                                      virtio_net_tx_complete);
667
        if (ret == 0) {
668
            virtio_queue_set_notification(n->tx_vq, 0);
669
            n->async_tx.elem = elem;
670
            n->async_tx.len  = len;
671
            return;
672
        }
673

    
674
        len += ret;
675

    
676
        virtqueue_push(vq, &elem, len);
677
        virtio_notify(&n->vdev, vq);
678
    }
679
}
680

    
681
static void virtio_net_handle_tx(VirtIODevice *vdev, VirtQueue *vq)
682
{
683
    VirtIONet *n = to_virtio_net(vdev);
684

    
685
    if (n->tx_timer_active) {
686
        virtio_queue_set_notification(vq, 1);
687
        qemu_del_timer(n->tx_timer);
688
        n->tx_timer_active = 0;
689
        virtio_net_flush_tx(n, vq);
690
    } else {
691
        qemu_mod_timer(n->tx_timer,
692
                       qemu_get_clock(vm_clock) + TX_TIMER_INTERVAL);
693
        n->tx_timer_active = 1;
694
        virtio_queue_set_notification(vq, 0);
695
    }
696
}
697

    
698
static void virtio_net_tx_timer(void *opaque)
699
{
700
    VirtIONet *n = opaque;
701

    
702
    n->tx_timer_active = 0;
703

    
704
    /* Just in case the driver is not ready on more */
705
    if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
706
        return;
707

    
708
    virtio_queue_set_notification(n->tx_vq, 1);
709
    virtio_net_flush_tx(n, n->tx_vq);
710
}
711

    
712
static void virtio_net_save(QEMUFile *f, void *opaque)
713
{
714
    VirtIONet *n = opaque;
715

    
716
    if (n->vhost_started) {
717
        /* TODO: should we really stop the backend?
718
         * If we don't, it might keep writing to memory. */
719
        vhost_net_stop(tap_get_vhost_net(n->nic->nc.peer), &n->vdev);
720
        n->vhost_started = 0;
721
    }
722
    virtio_save(&n->vdev, f);
723

    
724
    qemu_put_buffer(f, n->mac, ETH_ALEN);
725
    qemu_put_be32(f, n->tx_timer_active);
726
    qemu_put_be32(f, n->mergeable_rx_bufs);
727
    qemu_put_be16(f, n->status);
728
    qemu_put_byte(f, n->promisc);
729
    qemu_put_byte(f, n->allmulti);
730
    qemu_put_be32(f, n->mac_table.in_use);
731
    qemu_put_buffer(f, n->mac_table.macs, n->mac_table.in_use * ETH_ALEN);
732
    qemu_put_buffer(f, (uint8_t *)n->vlans, MAX_VLAN >> 3);
733
    qemu_put_be32(f, n->has_vnet_hdr);
734
    qemu_put_byte(f, n->mac_table.multi_overflow);
735
    qemu_put_byte(f, n->mac_table.uni_overflow);
736
    qemu_put_byte(f, n->alluni);
737
    qemu_put_byte(f, n->nomulti);
738
    qemu_put_byte(f, n->nouni);
739
    qemu_put_byte(f, n->nobcast);
740
    qemu_put_byte(f, n->has_ufo);
741
}
742

    
743
static int virtio_net_load(QEMUFile *f, void *opaque, int version_id)
744
{
745
    VirtIONet *n = opaque;
746
    int i;
747

    
748
    if (version_id < 2 || version_id > VIRTIO_NET_VM_VERSION)
749
        return -EINVAL;
750

    
751
    virtio_load(&n->vdev, f);
752

    
753
    qemu_get_buffer(f, n->mac, ETH_ALEN);
754
    n->tx_timer_active = qemu_get_be32(f);
755
    n->mergeable_rx_bufs = qemu_get_be32(f);
756

    
757
    if (version_id >= 3)
758
        n->status = qemu_get_be16(f);
759

    
760
    if (version_id >= 4) {
761
        if (version_id < 8) {
762
            n->promisc = qemu_get_be32(f);
763
            n->allmulti = qemu_get_be32(f);
764
        } else {
765
            n->promisc = qemu_get_byte(f);
766
            n->allmulti = qemu_get_byte(f);
767
        }
768
    }
769

    
770
    if (version_id >= 5) {
771
        n->mac_table.in_use = qemu_get_be32(f);
772
        /* MAC_TABLE_ENTRIES may be different from the saved image */
773
        if (n->mac_table.in_use <= MAC_TABLE_ENTRIES) {
774
            qemu_get_buffer(f, n->mac_table.macs,
775
                            n->mac_table.in_use * ETH_ALEN);
776
        } else if (n->mac_table.in_use) {
777
            qemu_fseek(f, n->mac_table.in_use * ETH_ALEN, SEEK_CUR);
778
            n->mac_table.multi_overflow = n->mac_table.uni_overflow = 1;
779
            n->mac_table.in_use = 0;
780
        }
781
    }
782
 
783
    if (version_id >= 6)
784
        qemu_get_buffer(f, (uint8_t *)n->vlans, MAX_VLAN >> 3);
785

    
786
    if (version_id >= 7) {
787
        if (qemu_get_be32(f) && !peer_has_vnet_hdr(n)) {
788
            error_report("virtio-net: saved image requires vnet_hdr=on");
789
            return -1;
790
        }
791

    
792
        if (n->has_vnet_hdr) {
793
            tap_using_vnet_hdr(n->nic->nc.peer, 1);
794
            tap_set_offload(n->nic->nc.peer,
795
                    (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_CSUM) & 1,
796
                    (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_TSO4) & 1,
797
                    (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_TSO6) & 1,
798
                    (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_ECN)  & 1,
799
                    (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_UFO)  & 1);
800
        }
801
    }
802

    
803
    if (version_id >= 9) {
804
        n->mac_table.multi_overflow = qemu_get_byte(f);
805
        n->mac_table.uni_overflow = qemu_get_byte(f);
806
    }
807

    
808
    if (version_id >= 10) {
809
        n->alluni = qemu_get_byte(f);
810
        n->nomulti = qemu_get_byte(f);
811
        n->nouni = qemu_get_byte(f);
812
        n->nobcast = qemu_get_byte(f);
813
    }
814

    
815
    if (version_id >= 11) {
816
        if (qemu_get_byte(f) && !peer_has_ufo(n)) {
817
            error_report("virtio-net: saved image requires TUN_F_UFO support");
818
            return -1;
819
        }
820
    }
821

    
822
    /* Find the first multicast entry in the saved MAC filter */
823
    for (i = 0; i < n->mac_table.in_use; i++) {
824
        if (n->mac_table.macs[i * ETH_ALEN] & 1) {
825
            break;
826
        }
827
    }
828
    n->mac_table.first_multi = i;
829

    
830
    if (n->tx_timer_active) {
831
        qemu_mod_timer(n->tx_timer,
832
                       qemu_get_clock(vm_clock) + TX_TIMER_INTERVAL);
833
    }
834
    return 0;
835
}
836

    
837
static void virtio_net_cleanup(VLANClientState *nc)
838
{
839
    VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
840

    
841
    n->nic = NULL;
842
}
843

    
844
static NetClientInfo net_virtio_info = {
845
    .type = NET_CLIENT_TYPE_NIC,
846
    .size = sizeof(NICState),
847
    .can_receive = virtio_net_can_receive,
848
    .receive = virtio_net_receive,
849
        .cleanup = virtio_net_cleanup,
850
    .link_status_changed = virtio_net_set_link_status,
851
};
852

    
853
static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status)
854
{
855
    VirtIONet *n = to_virtio_net(vdev);
856
    if (!n->nic->nc.peer) {
857
        return;
858
    }
859
    if (n->nic->nc.peer->info->type != NET_CLIENT_TYPE_TAP) {
860
        return;
861
    }
862

    
863
    if (!tap_get_vhost_net(n->nic->nc.peer)) {
864
        return;
865
    }
866
    if (!!n->vhost_started == !!(status & VIRTIO_CONFIG_S_DRIVER_OK)) {
867
        return;
868
    }
869
    if (status & VIRTIO_CONFIG_S_DRIVER_OK) {
870
        int r = vhost_net_start(tap_get_vhost_net(n->nic->nc.peer), vdev);
871
        if (r < 0) {
872
            fprintf(stderr, "unable to start vhost net: %d: "
873
                    "falling back on userspace virtio\n", -r);
874
        } else {
875
            n->vhost_started = 1;
876
        }
877
    } else {
878
        vhost_net_stop(tap_get_vhost_net(n->nic->nc.peer), vdev);
879
        n->vhost_started = 0;
880
    }
881
}
882

    
883
static void virtio_net_vmstate_change(void *opaque, int running, int reason)
884
{
885
    VirtIONet *n = opaque;
886
    if (!running) {
887
        return;
888
    }
889
    /* This is called when vm is started, it will start vhost backend if
890
     * appropriate e.g. after migration. */
891
    virtio_net_set_status(&n->vdev, n->vdev.status);
892
}
893

    
894
VirtIODevice *virtio_net_init(DeviceState *dev, NICConf *conf)
895
{
896
    VirtIONet *n;
897
    static int virtio_net_id;
898

    
899
    n = (VirtIONet *)virtio_common_init("virtio-net", VIRTIO_ID_NET,
900
                                        sizeof(struct virtio_net_config),
901
                                        sizeof(VirtIONet));
902

    
903
    n->vdev.get_config = virtio_net_get_config;
904
    n->vdev.set_config = virtio_net_set_config;
905
    n->vdev.get_features = virtio_net_get_features;
906
    n->vdev.set_features = virtio_net_set_features;
907
    n->vdev.bad_features = virtio_net_bad_features;
908
    n->vdev.reset = virtio_net_reset;
909
    n->vdev.set_status = virtio_net_set_status;
910
    n->rx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_rx);
911
    n->tx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_tx);
912
    n->ctrl_vq = virtio_add_queue(&n->vdev, 64, virtio_net_handle_ctrl);
913
    qemu_macaddr_default_if_unset(&conf->macaddr);
914
    memcpy(&n->mac[0], &conf->macaddr, sizeof(n->mac));
915
    n->status = VIRTIO_NET_S_LINK_UP;
916

    
917
    n->nic = qemu_new_nic(&net_virtio_info, conf, dev->info->name, dev->id, n);
918

    
919
    qemu_format_nic_info_str(&n->nic->nc, conf->macaddr.a);
920

    
921
    n->tx_timer = qemu_new_timer(vm_clock, virtio_net_tx_timer, n);
922
    n->tx_timer_active = 0;
923
    n->mergeable_rx_bufs = 0;
924
    n->promisc = 1; /* for compatibility */
925

    
926
    n->mac_table.macs = qemu_mallocz(MAC_TABLE_ENTRIES * ETH_ALEN);
927

    
928
    n->vlans = qemu_mallocz(MAX_VLAN >> 3);
929

    
930
    register_savevm("virtio-net", virtio_net_id++, VIRTIO_NET_VM_VERSION,
931
                    virtio_net_save, virtio_net_load, n);
932
    n->vmstate = qemu_add_vm_change_state_handler(virtio_net_vmstate_change, n);
933

    
934
    return &n->vdev;
935
}
936

    
937
void virtio_net_exit(VirtIODevice *vdev)
938
{
939
    VirtIONet *n = DO_UPCAST(VirtIONet, vdev, vdev);
940
    qemu_del_vm_change_state_handler(n->vmstate);
941

    
942
    if (n->vhost_started) {
943
        vhost_net_stop(tap_get_vhost_net(n->nic->nc.peer), vdev);
944
    }
945

    
946
    qemu_purge_queued_packets(&n->nic->nc);
947

    
948
    unregister_savevm("virtio-net", n);
949

    
950
    qemu_free(n->mac_table.macs);
951
    qemu_free(n->vlans);
952

    
953
    qemu_del_timer(n->tx_timer);
954
    qemu_free_timer(n->tx_timer);
955

    
956
    virtio_cleanup(&n->vdev);
957
    qemu_del_vlan_client(&n->nic->nc);
958
}