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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>
8
 *
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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 "iov.h"
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#include "virtio.h"
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#include "net.h"
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#include "net/checksum.h"
18
#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"
23

    
24
#define VIRTIO_NET_VM_VERSION    11
25

    
26
#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
    int tx_timer_active;
40
    uint32_t has_vnet_hdr;
41
    uint8_t has_ufo;
42
    struct {
43
        VirtQueueElement elem;
44
        ssize_t len;
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    } async_tx;
46
    int mergeable_rx_bufs;
47
    uint8_t promisc;
48
    uint8_t allmulti;
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    uint8_t alluni;
50
    uint8_t nomulti;
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    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;
57
        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;
64

    
65
/* TODO
66
 * - we could suppress RX interrupt if we were so inclined.
67
 */
68

    
69
static VirtIONet *to_virtio_net(VirtIODevice *vdev)
70
{
71
    return (VirtIONet *)vdev;
72
}
73

    
74
static void virtio_net_get_config(VirtIODevice *vdev, uint8_t *config)
75
{
76
    VirtIONet *n = to_virtio_net(vdev);
77
    struct virtio_net_config netcfg;
78

    
79
    netcfg.status = n->status;
80
    memcpy(netcfg.mac, n->mac, ETH_ALEN);
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    memcpy(config, &netcfg, sizeof(netcfg));
82
}
83

    
84
static void virtio_net_set_config(VirtIODevice *vdev, const uint8_t *config)
85
{
86
    VirtIONet *n = to_virtio_net(vdev);
87
    struct virtio_net_config netcfg;
88

    
89
    memcpy(&netcfg, config, sizeof(netcfg));
90

    
91
    if (memcmp(netcfg.mac, n->mac, ETH_ALEN)) {
92
        memcpy(n->mac, netcfg.mac, ETH_ALEN);
93
        qemu_format_nic_info_str(&n->nic->nc, n->mac);
94
    }
95
}
96

    
97
static void virtio_net_set_link_status(VLANClientState *nc)
98
{
99
    VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
100
    uint16_t old_status = n->status;
101

    
102
    if (nc->link_down)
103
        n->status &= ~VIRTIO_NET_S_LINK_UP;
104
    else
105
        n->status |= VIRTIO_NET_S_LINK_UP;
106

    
107
    if (n->status != old_status)
108
        virtio_notify_config(&n->vdev);
109
}
110

    
111
static void virtio_net_reset(VirtIODevice *vdev)
112
{
113
    VirtIONet *n = to_virtio_net(vdev);
114

    
115
    /* Reset back to compatibility mode */
116
    n->promisc = 1;
117
    n->allmulti = 0;
118
    n->alluni = 0;
119
    n->nomulti = 0;
120
    n->nouni = 0;
121
    n->nobcast = 0;
122
    if (n->vhost_started) {
123
        vhost_net_stop(tap_get_vhost_net(n->nic->nc.peer), vdev);
124
        n->vhost_started = 0;
125
    }
126

    
127
    /* Flush any MAC and VLAN filter table state */
128
    n->mac_table.in_use = 0;
129
    n->mac_table.first_multi = 0;
130
    n->mac_table.multi_overflow = 0;
131
    n->mac_table.uni_overflow = 0;
132
    memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
133
    memset(n->vlans, 0, MAX_VLAN >> 3);
134
}
135

    
136
static int peer_has_vnet_hdr(VirtIONet *n)
137
{
138
    if (!n->nic->nc.peer)
139
        return 0;
140

    
141
    if (n->nic->nc.peer->info->type != NET_CLIENT_TYPE_TAP)
142
        return 0;
143

    
144
    n->has_vnet_hdr = tap_has_vnet_hdr(n->nic->nc.peer);
145

    
146
    return n->has_vnet_hdr;
147
}
148

    
149
static int peer_has_ufo(VirtIONet *n)
150
{
151
    if (!peer_has_vnet_hdr(n))
152
        return 0;
153

    
154
    n->has_ufo = tap_has_ufo(n->nic->nc.peer);
155

    
156
    return n->has_ufo;
157
}
158

    
159
static uint32_t virtio_net_get_features(VirtIODevice *vdev, uint32_t features)
160
{
161
    VirtIONet *n = to_virtio_net(vdev);
162

    
163
    features |= (1 << VIRTIO_NET_F_MAC);
164

    
165
    if (peer_has_vnet_hdr(n)) {
166
        tap_using_vnet_hdr(n->nic->nc.peer, 1);
167
    } else {
168
        features &= ~(0x1 << VIRTIO_NET_F_CSUM);
169
        features &= ~(0x1 << VIRTIO_NET_F_HOST_TSO4);
170
        features &= ~(0x1 << VIRTIO_NET_F_HOST_TSO6);
171
        features &= ~(0x1 << VIRTIO_NET_F_HOST_ECN);
172

    
173
        features &= ~(0x1 << VIRTIO_NET_F_GUEST_CSUM);
174
        features &= ~(0x1 << VIRTIO_NET_F_GUEST_TSO4);
175
        features &= ~(0x1 << VIRTIO_NET_F_GUEST_TSO6);
176
        features &= ~(0x1 << VIRTIO_NET_F_GUEST_ECN);
177
    }
178

    
179
    if (!peer_has_vnet_hdr(n) || !peer_has_ufo(n)) {
180
        features &= ~(0x1 << VIRTIO_NET_F_GUEST_UFO);
181
        features &= ~(0x1 << VIRTIO_NET_F_HOST_UFO);
182
    }
183

    
184
    if (!n->nic->nc.peer ||
185
        n->nic->nc.peer->info->type != NET_CLIENT_TYPE_TAP) {
186
        return features;
187
    }
188
    if (!tap_get_vhost_net(n->nic->nc.peer)) {
189
        return features;
190
    }
191
    return vhost_net_get_features(tap_get_vhost_net(n->nic->nc.peer), features);
192
}
193

    
194
static uint32_t virtio_net_bad_features(VirtIODevice *vdev)
195
{
196
    uint32_t features = 0;
197

    
198
    /* Linux kernel 2.6.25.  It understood MAC (as everyone must),
199
     * but also these: */
200
    features |= (1 << VIRTIO_NET_F_MAC);
201
    features |= (1 << VIRTIO_NET_F_CSUM);
202
    features |= (1 << VIRTIO_NET_F_HOST_TSO4);
203
    features |= (1 << VIRTIO_NET_F_HOST_TSO6);
204
    features |= (1 << VIRTIO_NET_F_HOST_ECN);
205

    
206
    return features;
207
}
208

    
209
static void virtio_net_set_features(VirtIODevice *vdev, uint32_t features)
210
{
211
    VirtIONet *n = to_virtio_net(vdev);
212

    
213
    n->mergeable_rx_bufs = !!(features & (1 << VIRTIO_NET_F_MRG_RXBUF));
214

    
215
    if (n->has_vnet_hdr) {
216
        tap_set_offload(n->nic->nc.peer,
217
                        (features >> VIRTIO_NET_F_GUEST_CSUM) & 1,
218
                        (features >> VIRTIO_NET_F_GUEST_TSO4) & 1,
219
                        (features >> VIRTIO_NET_F_GUEST_TSO6) & 1,
220
                        (features >> VIRTIO_NET_F_GUEST_ECN)  & 1,
221
                        (features >> VIRTIO_NET_F_GUEST_UFO)  & 1);
222
    }
223
    if (!n->nic->nc.peer ||
224
        n->nic->nc.peer->info->type != NET_CLIENT_TYPE_TAP) {
225
        return;
226
    }
227
    if (!tap_get_vhost_net(n->nic->nc.peer)) {
228
        return;
229
    }
230
    vhost_net_ack_features(tap_get_vhost_net(n->nic->nc.peer), features);
231
}
232

    
233
static int virtio_net_handle_rx_mode(VirtIONet *n, uint8_t cmd,
234
                                     VirtQueueElement *elem)
235
{
236
    uint8_t on;
237

    
238
    if (elem->out_num != 2 || elem->out_sg[1].iov_len != sizeof(on)) {
239
        fprintf(stderr, "virtio-net ctrl invalid rx mode command\n");
240
        exit(1);
241
    }
242

    
243
    on = ldub_p(elem->out_sg[1].iov_base);
244

    
245
    if (cmd == VIRTIO_NET_CTRL_RX_MODE_PROMISC)
246
        n->promisc = on;
247
    else if (cmd == VIRTIO_NET_CTRL_RX_MODE_ALLMULTI)
248
        n->allmulti = on;
249
    else if (cmd == VIRTIO_NET_CTRL_RX_MODE_ALLUNI)
250
        n->alluni = on;
251
    else if (cmd == VIRTIO_NET_CTRL_RX_MODE_NOMULTI)
252
        n->nomulti = on;
253
    else if (cmd == VIRTIO_NET_CTRL_RX_MODE_NOUNI)
254
        n->nouni = on;
255
    else if (cmd == VIRTIO_NET_CTRL_RX_MODE_NOBCAST)
256
        n->nobcast = on;
257
    else
258
        return VIRTIO_NET_ERR;
259

    
260
    return VIRTIO_NET_OK;
261
}
262

    
263
static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd,
264
                                 VirtQueueElement *elem)
265
{
266
    struct virtio_net_ctrl_mac mac_data;
267

    
268
    if (cmd != VIRTIO_NET_CTRL_MAC_TABLE_SET || elem->out_num != 3 ||
269
        elem->out_sg[1].iov_len < sizeof(mac_data) ||
270
        elem->out_sg[2].iov_len < sizeof(mac_data))
271
        return VIRTIO_NET_ERR;
272

    
273
    n->mac_table.in_use = 0;
274
    n->mac_table.first_multi = 0;
275
    n->mac_table.uni_overflow = 0;
276
    n->mac_table.multi_overflow = 0;
277
    memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
278

    
279
    mac_data.entries = ldl_le_p(elem->out_sg[1].iov_base);
280

    
281
    if (sizeof(mac_data.entries) +
282
        (mac_data.entries * ETH_ALEN) > elem->out_sg[1].iov_len)
283
        return VIRTIO_NET_ERR;
284

    
285
    if (mac_data.entries <= MAC_TABLE_ENTRIES) {
286
        memcpy(n->mac_table.macs, elem->out_sg[1].iov_base + sizeof(mac_data),
287
               mac_data.entries * ETH_ALEN);
288
        n->mac_table.in_use += mac_data.entries;
289
    } else {
290
        n->mac_table.uni_overflow = 1;
291
    }
292

    
293
    n->mac_table.first_multi = n->mac_table.in_use;
294

    
295
    mac_data.entries = ldl_le_p(elem->out_sg[2].iov_base);
296

    
297
    if (sizeof(mac_data.entries) +
298
        (mac_data.entries * ETH_ALEN) > elem->out_sg[2].iov_len)
299
        return VIRTIO_NET_ERR;
300

    
301
    if (mac_data.entries) {
302
        if (n->mac_table.in_use + mac_data.entries <= MAC_TABLE_ENTRIES) {
303
            memcpy(n->mac_table.macs + (n->mac_table.in_use * ETH_ALEN),
304
                   elem->out_sg[2].iov_base + sizeof(mac_data),
305
                   mac_data.entries * ETH_ALEN);
306
            n->mac_table.in_use += mac_data.entries;
307
        } else {
308
            n->mac_table.multi_overflow = 1;
309
        }
310
    }
311

    
312
    return VIRTIO_NET_OK;
313
}
314

    
315
static int virtio_net_handle_vlan_table(VirtIONet *n, uint8_t cmd,
316
                                        VirtQueueElement *elem)
317
{
318
    uint16_t vid;
319

    
320
    if (elem->out_num != 2 || elem->out_sg[1].iov_len != sizeof(vid)) {
321
        fprintf(stderr, "virtio-net ctrl invalid vlan command\n");
322
        return VIRTIO_NET_ERR;
323
    }
324

    
325
    vid = lduw_le_p(elem->out_sg[1].iov_base);
326

    
327
    if (vid >= MAX_VLAN)
328
        return VIRTIO_NET_ERR;
329

    
330
    if (cmd == VIRTIO_NET_CTRL_VLAN_ADD)
331
        n->vlans[vid >> 5] |= (1U << (vid & 0x1f));
332
    else if (cmd == VIRTIO_NET_CTRL_VLAN_DEL)
333
        n->vlans[vid >> 5] &= ~(1U << (vid & 0x1f));
334
    else
335
        return VIRTIO_NET_ERR;
336

    
337
    return VIRTIO_NET_OK;
338
}
339

    
340
static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
341
{
342
    VirtIONet *n = to_virtio_net(vdev);
343
    struct virtio_net_ctrl_hdr ctrl;
344
    virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
345
    VirtQueueElement elem;
346

    
347
    while (virtqueue_pop(vq, &elem)) {
348
        if ((elem.in_num < 1) || (elem.out_num < 1)) {
349
            fprintf(stderr, "virtio-net ctrl missing headers\n");
350
            exit(1);
351
        }
352

    
353
        if (elem.out_sg[0].iov_len < sizeof(ctrl) ||
354
            elem.in_sg[elem.in_num - 1].iov_len < sizeof(status)) {
355
            fprintf(stderr, "virtio-net ctrl header not in correct element\n");
356
            exit(1);
357
        }
358

    
359
        ctrl.class = ldub_p(elem.out_sg[0].iov_base);
360
        ctrl.cmd = ldub_p(elem.out_sg[0].iov_base + sizeof(ctrl.class));
361

    
362
        if (ctrl.class == VIRTIO_NET_CTRL_RX_MODE)
363
            status = virtio_net_handle_rx_mode(n, ctrl.cmd, &elem);
364
        else if (ctrl.class == VIRTIO_NET_CTRL_MAC)
365
            status = virtio_net_handle_mac(n, ctrl.cmd, &elem);
366
        else if (ctrl.class == VIRTIO_NET_CTRL_VLAN)
367
            status = virtio_net_handle_vlan_table(n, ctrl.cmd, &elem);
368

    
369
        stb_p(elem.in_sg[elem.in_num - 1].iov_base, status);
370

    
371
        virtqueue_push(vq, &elem, sizeof(status));
372
        virtio_notify(vdev, vq);
373
    }
374
}
375

    
376
/* RX */
377

    
378
static void virtio_net_handle_rx(VirtIODevice *vdev, VirtQueue *vq)
379
{
380
    VirtIONet *n = to_virtio_net(vdev);
381

    
382
    qemu_flush_queued_packets(&n->nic->nc);
383

    
384
    /* We now have RX buffers, signal to the IO thread to break out of the
385
     * select to re-poll the tap file descriptor */
386
    qemu_notify_event();
387
}
388

    
389
static int virtio_net_can_receive(VLANClientState *nc)
390
{
391
    VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
392

    
393
    if (!virtio_queue_ready(n->rx_vq) ||
394
        !(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
395
        return 0;
396

    
397
    return 1;
398
}
399

    
400
static int virtio_net_has_buffers(VirtIONet *n, int bufsize)
401
{
402
    if (virtio_queue_empty(n->rx_vq) ||
403
        (n->mergeable_rx_bufs &&
404
         !virtqueue_avail_bytes(n->rx_vq, bufsize, 0))) {
405
        virtio_queue_set_notification(n->rx_vq, 1);
406

    
407
        /* To avoid a race condition where the guest has made some buffers
408
         * available after the above check but before notification was
409
         * enabled, check for available buffers again.
410
         */
411
        if (virtio_queue_empty(n->rx_vq) ||
412
            (n->mergeable_rx_bufs &&
413
             !virtqueue_avail_bytes(n->rx_vq, bufsize, 0)))
414
            return 0;
415
    }
416

    
417
    virtio_queue_set_notification(n->rx_vq, 0);
418
    return 1;
419
}
420

    
421
/* dhclient uses AF_PACKET but doesn't pass auxdata to the kernel so
422
 * it never finds out that the packets don't have valid checksums.  This
423
 * causes dhclient to get upset.  Fedora's carried a patch for ages to
424
 * fix this with Xen but it hasn't appeared in an upstream release of
425
 * dhclient yet.
426
 *
427
 * To avoid breaking existing guests, we catch udp packets and add
428
 * checksums.  This is terrible but it's better than hacking the guest
429
 * kernels.
430
 *
431
 * N.B. if we introduce a zero-copy API, this operation is no longer free so
432
 * we should provide a mechanism to disable it to avoid polluting the host
433
 * cache.
434
 */
435
static void work_around_broken_dhclient(struct virtio_net_hdr *hdr,
436
                                        const uint8_t *buf, size_t size)
437
{
438
    if ((hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && /* missing csum */
439
        (size > 27 && size < 1500) && /* normal sized MTU */
440
        (buf[12] == 0x08 && buf[13] == 0x00) && /* ethertype == IPv4 */
441
        (buf[23] == 17) && /* ip.protocol == UDP */
442
        (buf[34] == 0 && buf[35] == 67)) { /* udp.srcport == bootps */
443
        /* FIXME this cast is evil */
444
        net_checksum_calculate((uint8_t *)buf, size);
445
        hdr->flags &= ~VIRTIO_NET_HDR_F_NEEDS_CSUM;
446
    }
447
}
448

    
449
static int receive_header(VirtIONet *n, struct iovec *iov, int iovcnt,
450
                          const void *buf, size_t size, size_t hdr_len)
451
{
452
    struct virtio_net_hdr *hdr = (struct virtio_net_hdr *)iov[0].iov_base;
453
    int offset = 0;
454

    
455
    hdr->flags = 0;
456
    hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
457

    
458
    if (n->has_vnet_hdr) {
459
        memcpy(hdr, buf, sizeof(*hdr));
460
        offset = sizeof(*hdr);
461
        work_around_broken_dhclient(hdr, buf + offset, size - offset);
462
    }
463

    
464
    /* We only ever receive a struct virtio_net_hdr from the tapfd,
465
     * but we may be passing along a larger header to the guest.
466
     */
467
    iov[0].iov_base += hdr_len;
468
    iov[0].iov_len  -= hdr_len;
469

    
470
    return offset;
471
}
472

    
473
static int receive_filter(VirtIONet *n, const uint8_t *buf, int size)
474
{
475
    static const uint8_t bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
476
    static const uint8_t vlan[] = {0x81, 0x00};
477
    uint8_t *ptr = (uint8_t *)buf;
478
    int i;
479

    
480
    if (n->promisc)
481
        return 1;
482

    
483
    if (n->has_vnet_hdr) {
484
        ptr += sizeof(struct virtio_net_hdr);
485
    }
486

    
487
    if (!memcmp(&ptr[12], vlan, sizeof(vlan))) {
488
        int vid = be16_to_cpup((uint16_t *)(ptr + 14)) & 0xfff;
489
        if (!(n->vlans[vid >> 5] & (1U << (vid & 0x1f))))
490
            return 0;
491
    }
492

    
493
    if (ptr[0] & 1) { // multicast
494
        if (!memcmp(ptr, bcast, sizeof(bcast))) {
495
            return !n->nobcast;
496
        } else if (n->nomulti) {
497
            return 0;
498
        } else if (n->allmulti || n->mac_table.multi_overflow) {
499
            return 1;
500
        }
501

    
502
        for (i = n->mac_table.first_multi; i < n->mac_table.in_use; i++) {
503
            if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN)) {
504
                return 1;
505
            }
506
        }
507
    } else { // unicast
508
        if (n->nouni) {
509
            return 0;
510
        } else if (n->alluni || n->mac_table.uni_overflow) {
511
            return 1;
512
        } else if (!memcmp(ptr, n->mac, ETH_ALEN)) {
513
            return 1;
514
        }
515

    
516
        for (i = 0; i < n->mac_table.first_multi; i++) {
517
            if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN)) {
518
                return 1;
519
            }
520
        }
521
    }
522

    
523
    return 0;
524
}
525

    
526
static ssize_t virtio_net_receive(VLANClientState *nc, const uint8_t *buf, size_t size)
527
{
528
    VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
529
    struct virtio_net_hdr_mrg_rxbuf *mhdr = NULL;
530
    size_t hdr_len, offset, i;
531

    
532
    if (!virtio_net_can_receive(&n->nic->nc))
533
        return -1;
534

    
535
    /* hdr_len refers to the header we supply to the guest */
536
    hdr_len = n->mergeable_rx_bufs ?
537
        sizeof(struct virtio_net_hdr_mrg_rxbuf) : sizeof(struct virtio_net_hdr);
538

    
539

    
540
    if (!virtio_net_has_buffers(n, size + hdr_len))
541
        return 0;
542

    
543
    if (!receive_filter(n, buf, size))
544
        return size;
545

    
546
    offset = i = 0;
547

    
548
    while (offset < size) {
549
        VirtQueueElement elem;
550
        int len, total;
551
        struct iovec sg[VIRTQUEUE_MAX_SIZE];
552

    
553
        total = 0;
554

    
555
        if ((i != 0 && !n->mergeable_rx_bufs) ||
556
            virtqueue_pop(n->rx_vq, &elem) == 0) {
557
            if (i == 0)
558
                return -1;
559
            fprintf(stderr, "virtio-net truncating packet: "
560
                    "offset %zd, size %zd, hdr_len %zd\n",
561
                    offset, size, hdr_len);
562
            exit(1);
563
        }
564

    
565
        if (elem.in_num < 1) {
566
            fprintf(stderr, "virtio-net receive queue contains no in buffers\n");
567
            exit(1);
568
        }
569

    
570
        if (!n->mergeable_rx_bufs && elem.in_sg[0].iov_len != hdr_len) {
571
            fprintf(stderr, "virtio-net header not in first element\n");
572
            exit(1);
573
        }
574

    
575
        memcpy(&sg, &elem.in_sg[0], sizeof(sg[0]) * elem.in_num);
576

    
577
        if (i == 0) {
578
            if (n->mergeable_rx_bufs)
579
                mhdr = (struct virtio_net_hdr_mrg_rxbuf *)sg[0].iov_base;
580

    
581
            offset += receive_header(n, sg, elem.in_num,
582
                                     buf + offset, size - offset, hdr_len);
583
            total += hdr_len;
584
        }
585

    
586
        /* copy in packet.  ugh */
587
        len = iov_from_buf(sg, elem.in_num,
588
                           buf + offset, size - offset);
589
        total += len;
590

    
591
        /* signal other side */
592
        virtqueue_fill(n->rx_vq, &elem, total, i++);
593

    
594
        offset += len;
595
    }
596

    
597
    if (mhdr)
598
        mhdr->num_buffers = i;
599

    
600
    virtqueue_flush(n->rx_vq, i);
601
    virtio_notify(&n->vdev, n->rx_vq);
602

    
603
    return size;
604
}
605

    
606
static void virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq);
607

    
608
static void virtio_net_tx_complete(VLANClientState *nc, ssize_t len)
609
{
610
    VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
611

    
612
    virtqueue_push(n->tx_vq, &n->async_tx.elem, n->async_tx.len);
613
    virtio_notify(&n->vdev, n->tx_vq);
614

    
615
    n->async_tx.elem.out_num = n->async_tx.len = 0;
616

    
617
    virtio_queue_set_notification(n->tx_vq, 1);
618
    virtio_net_flush_tx(n, n->tx_vq);
619
}
620

    
621
/* TX */
622
static void virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq)
623
{
624
    VirtQueueElement elem;
625

    
626
    if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
627
        return;
628

    
629
    if (n->async_tx.elem.out_num) {
630
        virtio_queue_set_notification(n->tx_vq, 0);
631
        return;
632
    }
633

    
634
    while (virtqueue_pop(vq, &elem)) {
635
        ssize_t ret, len = 0;
636
        unsigned int out_num = elem.out_num;
637
        struct iovec *out_sg = &elem.out_sg[0];
638
        unsigned hdr_len;
639

    
640
        /* hdr_len refers to the header received from the guest */
641
        hdr_len = n->mergeable_rx_bufs ?
642
            sizeof(struct virtio_net_hdr_mrg_rxbuf) :
643
            sizeof(struct virtio_net_hdr);
644

    
645
        if (out_num < 1 || out_sg->iov_len != hdr_len) {
646
            fprintf(stderr, "virtio-net header not in first element\n");
647
            exit(1);
648
        }
649

    
650
        /* ignore the header if GSO is not supported */
651
        if (!n->has_vnet_hdr) {
652
            out_num--;
653
            out_sg++;
654
            len += hdr_len;
655
        } else if (n->mergeable_rx_bufs) {
656
            /* tapfd expects a struct virtio_net_hdr */
657
            hdr_len -= sizeof(struct virtio_net_hdr);
658
            out_sg->iov_len -= hdr_len;
659
            len += hdr_len;
660
        }
661

    
662
        ret = qemu_sendv_packet_async(&n->nic->nc, out_sg, out_num,
663
                                      virtio_net_tx_complete);
664
        if (ret == 0) {
665
            virtio_queue_set_notification(n->tx_vq, 0);
666
            n->async_tx.elem = elem;
667
            n->async_tx.len  = len;
668
            return;
669
        }
670

    
671
        len += ret;
672

    
673
        virtqueue_push(vq, &elem, len);
674
        virtio_notify(&n->vdev, vq);
675
    }
676
}
677

    
678
static void virtio_net_handle_tx(VirtIODevice *vdev, VirtQueue *vq)
679
{
680
    VirtIONet *n = to_virtio_net(vdev);
681

    
682
    if (n->tx_timer_active) {
683
        virtio_queue_set_notification(vq, 1);
684
        qemu_del_timer(n->tx_timer);
685
        n->tx_timer_active = 0;
686
        virtio_net_flush_tx(n, vq);
687
    } else {
688
        qemu_mod_timer(n->tx_timer,
689
                       qemu_get_clock(vm_clock) + TX_TIMER_INTERVAL);
690
        n->tx_timer_active = 1;
691
        virtio_queue_set_notification(vq, 0);
692
    }
693
}
694

    
695
static void virtio_net_tx_timer(void *opaque)
696
{
697
    VirtIONet *n = opaque;
698

    
699
    n->tx_timer_active = 0;
700

    
701
    /* Just in case the driver is not ready on more */
702
    if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
703
        return;
704

    
705
    virtio_queue_set_notification(n->tx_vq, 1);
706
    virtio_net_flush_tx(n, n->tx_vq);
707
}
708

    
709
static void virtio_net_save(QEMUFile *f, void *opaque)
710
{
711
    VirtIONet *n = opaque;
712

    
713
    if (n->vhost_started) {
714
        /* TODO: should we really stop the backend?
715
         * If we don't, it might keep writing to memory. */
716
        vhost_net_stop(tap_get_vhost_net(n->nic->nc.peer), &n->vdev);
717
        n->vhost_started = 0;
718
    }
719
    virtio_save(&n->vdev, f);
720

    
721
    qemu_put_buffer(f, n->mac, ETH_ALEN);
722
    qemu_put_be32(f, n->tx_timer_active);
723
    qemu_put_be32(f, n->mergeable_rx_bufs);
724
    qemu_put_be16(f, n->status);
725
    qemu_put_byte(f, n->promisc);
726
    qemu_put_byte(f, n->allmulti);
727
    qemu_put_be32(f, n->mac_table.in_use);
728
    qemu_put_buffer(f, n->mac_table.macs, n->mac_table.in_use * ETH_ALEN);
729
    qemu_put_buffer(f, (uint8_t *)n->vlans, MAX_VLAN >> 3);
730
    qemu_put_be32(f, n->has_vnet_hdr);
731
    qemu_put_byte(f, n->mac_table.multi_overflow);
732
    qemu_put_byte(f, n->mac_table.uni_overflow);
733
    qemu_put_byte(f, n->alluni);
734
    qemu_put_byte(f, n->nomulti);
735
    qemu_put_byte(f, n->nouni);
736
    qemu_put_byte(f, n->nobcast);
737
    qemu_put_byte(f, n->has_ufo);
738
}
739

    
740
static int virtio_net_load(QEMUFile *f, void *opaque, int version_id)
741
{
742
    VirtIONet *n = opaque;
743
    int i;
744

    
745
    if (version_id < 2 || version_id > VIRTIO_NET_VM_VERSION)
746
        return -EINVAL;
747

    
748
    virtio_load(&n->vdev, f);
749

    
750
    qemu_get_buffer(f, n->mac, ETH_ALEN);
751
    n->tx_timer_active = qemu_get_be32(f);
752
    n->mergeable_rx_bufs = qemu_get_be32(f);
753

    
754
    if (version_id >= 3)
755
        n->status = qemu_get_be16(f);
756

    
757
    if (version_id >= 4) {
758
        if (version_id < 8) {
759
            n->promisc = qemu_get_be32(f);
760
            n->allmulti = qemu_get_be32(f);
761
        } else {
762
            n->promisc = qemu_get_byte(f);
763
            n->allmulti = qemu_get_byte(f);
764
        }
765
    }
766

    
767
    if (version_id >= 5) {
768
        n->mac_table.in_use = qemu_get_be32(f);
769
        /* MAC_TABLE_ENTRIES may be different from the saved image */
770
        if (n->mac_table.in_use <= MAC_TABLE_ENTRIES) {
771
            qemu_get_buffer(f, n->mac_table.macs,
772
                            n->mac_table.in_use * ETH_ALEN);
773
        } else if (n->mac_table.in_use) {
774
            qemu_fseek(f, n->mac_table.in_use * ETH_ALEN, SEEK_CUR);
775
            n->mac_table.multi_overflow = n->mac_table.uni_overflow = 1;
776
            n->mac_table.in_use = 0;
777
        }
778
    }
779
 
780
    if (version_id >= 6)
781
        qemu_get_buffer(f, (uint8_t *)n->vlans, MAX_VLAN >> 3);
782

    
783
    if (version_id >= 7) {
784
        if (qemu_get_be32(f) && !peer_has_vnet_hdr(n)) {
785
            error_report("virtio-net: saved image requires vnet_hdr=on");
786
            return -1;
787
        }
788

    
789
        if (n->has_vnet_hdr) {
790
            tap_using_vnet_hdr(n->nic->nc.peer, 1);
791
            tap_set_offload(n->nic->nc.peer,
792
                    (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_CSUM) & 1,
793
                    (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_TSO4) & 1,
794
                    (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_TSO6) & 1,
795
                    (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_ECN)  & 1,
796
                    (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_UFO)  & 1);
797
        }
798
    }
799

    
800
    if (version_id >= 9) {
801
        n->mac_table.multi_overflow = qemu_get_byte(f);
802
        n->mac_table.uni_overflow = qemu_get_byte(f);
803
    }
804

    
805
    if (version_id >= 10) {
806
        n->alluni = qemu_get_byte(f);
807
        n->nomulti = qemu_get_byte(f);
808
        n->nouni = qemu_get_byte(f);
809
        n->nobcast = qemu_get_byte(f);
810
    }
811

    
812
    if (version_id >= 11) {
813
        if (qemu_get_byte(f) && !peer_has_ufo(n)) {
814
            error_report("virtio-net: saved image requires TUN_F_UFO support");
815
            return -1;
816
        }
817
    }
818

    
819
    /* Find the first multicast entry in the saved MAC filter */
820
    for (i = 0; i < n->mac_table.in_use; i++) {
821
        if (n->mac_table.macs[i * ETH_ALEN] & 1) {
822
            break;
823
        }
824
    }
825
    n->mac_table.first_multi = i;
826

    
827
    if (n->tx_timer_active) {
828
        qemu_mod_timer(n->tx_timer,
829
                       qemu_get_clock(vm_clock) + TX_TIMER_INTERVAL);
830
    }
831
    return 0;
832
}
833

    
834
static void virtio_net_cleanup(VLANClientState *nc)
835
{
836
    VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
837

    
838
    n->nic = NULL;
839
}
840

    
841
static NetClientInfo net_virtio_info = {
842
    .type = NET_CLIENT_TYPE_NIC,
843
    .size = sizeof(NICState),
844
    .can_receive = virtio_net_can_receive,
845
    .receive = virtio_net_receive,
846
        .cleanup = virtio_net_cleanup,
847
    .link_status_changed = virtio_net_set_link_status,
848
};
849

    
850
static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status)
851
{
852
    VirtIONet *n = to_virtio_net(vdev);
853
    if (!n->nic->nc.peer) {
854
        return;
855
    }
856
    if (n->nic->nc.peer->info->type != NET_CLIENT_TYPE_TAP) {
857
        return;
858
    }
859

    
860
    if (!tap_get_vhost_net(n->nic->nc.peer)) {
861
        return;
862
    }
863
    if (!!n->vhost_started == !!(status & VIRTIO_CONFIG_S_DRIVER_OK)) {
864
        return;
865
    }
866
    if (status & VIRTIO_CONFIG_S_DRIVER_OK) {
867
        int r = vhost_net_start(tap_get_vhost_net(n->nic->nc.peer), vdev);
868
        if (r < 0) {
869
            fprintf(stderr, "unable to start vhost net: %d: "
870
                    "falling back on userspace virtio\n", -r);
871
        } else {
872
            n->vhost_started = 1;
873
        }
874
    } else {
875
        vhost_net_stop(tap_get_vhost_net(n->nic->nc.peer), vdev);
876
        n->vhost_started = 0;
877
    }
878
}
879

    
880
static void virtio_net_vmstate_change(void *opaque, int running, int reason)
881
{
882
    VirtIONet *n = opaque;
883
    uint8_t status = running ? VIRTIO_CONFIG_S_DRIVER_OK : 0;
884
    /* This is called when vm is started/stopped,
885
     * it will start/stop vhost backend if * appropriate
886
     * e.g. after migration. */
887
    virtio_net_set_status(&n->vdev, n->vdev.status & status);
888
}
889

    
890
VirtIODevice *virtio_net_init(DeviceState *dev, NICConf *conf)
891
{
892
    VirtIONet *n;
893
    static int virtio_net_id;
894

    
895
    n = (VirtIONet *)virtio_common_init("virtio-net", VIRTIO_ID_NET,
896
                                        sizeof(struct virtio_net_config),
897
                                        sizeof(VirtIONet));
898

    
899
    n->vdev.get_config = virtio_net_get_config;
900
    n->vdev.set_config = virtio_net_set_config;
901
    n->vdev.get_features = virtio_net_get_features;
902
    n->vdev.set_features = virtio_net_set_features;
903
    n->vdev.bad_features = virtio_net_bad_features;
904
    n->vdev.reset = virtio_net_reset;
905
    n->vdev.set_status = virtio_net_set_status;
906
    n->rx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_rx);
907
    n->tx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_tx);
908
    n->ctrl_vq = virtio_add_queue(&n->vdev, 64, virtio_net_handle_ctrl);
909
    qemu_macaddr_default_if_unset(&conf->macaddr);
910
    memcpy(&n->mac[0], &conf->macaddr, sizeof(n->mac));
911
    n->status = VIRTIO_NET_S_LINK_UP;
912

    
913
    n->nic = qemu_new_nic(&net_virtio_info, conf, dev->info->name, dev->id, n);
914

    
915
    qemu_format_nic_info_str(&n->nic->nc, conf->macaddr.a);
916

    
917
    n->tx_timer = qemu_new_timer(vm_clock, virtio_net_tx_timer, n);
918
    n->tx_timer_active = 0;
919
    n->mergeable_rx_bufs = 0;
920
    n->promisc = 1; /* for compatibility */
921

    
922
    n->mac_table.macs = qemu_mallocz(MAC_TABLE_ENTRIES * ETH_ALEN);
923

    
924
    n->vlans = qemu_mallocz(MAX_VLAN >> 3);
925

    
926
    register_savevm(NULL, "virtio-net", virtio_net_id++, VIRTIO_NET_VM_VERSION,
927
                    virtio_net_save, virtio_net_load, n);
928
    n->vmstate = qemu_add_vm_change_state_handler(virtio_net_vmstate_change, n);
929

    
930
    return &n->vdev;
931
}
932

    
933
void virtio_net_exit(VirtIODevice *vdev)
934
{
935
    VirtIONet *n = DO_UPCAST(VirtIONet, vdev, vdev);
936
    qemu_del_vm_change_state_handler(n->vmstate);
937

    
938
    if (n->vhost_started) {
939
        vhost_net_stop(tap_get_vhost_net(n->nic->nc.peer), vdev);
940
    }
941

    
942
    qemu_purge_queued_packets(&n->nic->nc);
943

    
944
    unregister_savevm(NULL, "virtio-net", n);
945

    
946
    qemu_free(n->mac_table.macs);
947
    qemu_free(n->vlans);
948

    
949
    qemu_del_timer(n->tx_timer);
950
    qemu_free_timer(n->tx_timer);
951

    
952
    virtio_cleanup(&n->vdev);
953
    qemu_del_vlan_client(&n->nic->nc);
954
}