1#include <linux/etherdevice.h>
2#include <linux/if_macvlan.h>
3#include <linux/if_vlan.h>
4#include <linux/interrupt.h>
5#include <linux/nsproxy.h>
6#include <linux/compat.h>
7#include <linux/if_tun.h>
8#include <linux/module.h>
9#include <linux/skbuff.h>
10#include <linux/cache.h>
11#include <linux/sched.h>
12#include <linux/types.h>
13#include <linux/slab.h>
14#include <linux/init.h>
15#include <linux/wait.h>
16#include <linux/cdev.h>
17#include <linux/idr.h>
18#include <linux/fs.h>
19
20#include <net/net_namespace.h>
21#include <net/rtnetlink.h>
22#include <net/sock.h>
23#include <linux/virtio_net.h>
24
25
26
27
28
29
30
31
32
33
34
35struct macvtap_queue {
36 struct sock sk;
37 struct socket sock;
38 struct socket_wq wq;
39 int vnet_hdr_sz;
40 struct macvlan_dev __rcu *vlan;
41 struct file *file;
42 unsigned int flags;
43 u16 queue_index;
44 bool enabled;
45 struct list_head next;
46};
47
48static struct proto macvtap_proto = {
49 .name = "macvtap",
50 .owner = THIS_MODULE,
51 .obj_size = sizeof (struct macvtap_queue),
52};
53
54
55
56
57static dev_t macvtap_major;
58#define MACVTAP_NUM_DEVS (1U << MINORBITS)
59static DEFINE_MUTEX(minor_lock);
60static DEFINE_IDR(minor_idr);
61
62#define GOODCOPY_LEN 128
63static struct class *macvtap_class;
64static struct cdev macvtap_cdev;
65
66static const struct proto_ops macvtap_socket_ops;
67
68#define TUN_OFFLOADS (NETIF_F_HW_CSUM | NETIF_F_TSO_ECN | NETIF_F_TSO | \
69 NETIF_F_TSO6 | NETIF_F_UFO)
70#define RX_OFFLOADS (NETIF_F_GRO | NETIF_F_LRO)
71#define TAP_FEATURES (NETIF_F_GSO | NETIF_F_SG)
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90static int macvtap_enable_queue(struct net_device *dev, struct file *file,
91 struct macvtap_queue *q)
92{
93 struct macvlan_dev *vlan = netdev_priv(dev);
94 int err = -EINVAL;
95
96 ASSERT_RTNL();
97
98 if (q->enabled)
99 goto out;
100
101 err = 0;
102 rcu_assign_pointer(vlan->taps[vlan->numvtaps], q);
103 q->queue_index = vlan->numvtaps;
104 q->enabled = true;
105
106 vlan->numvtaps++;
107out:
108 return err;
109}
110
111static int macvtap_set_queue(struct net_device *dev, struct file *file,
112 struct macvtap_queue *q)
113{
114 struct macvlan_dev *vlan = netdev_priv(dev);
115 int err = -EBUSY;
116
117 rtnl_lock();
118 if (vlan->numqueues == MAX_MACVTAP_QUEUES)
119 goto out;
120
121 err = 0;
122 rcu_assign_pointer(q->vlan, vlan);
123 rcu_assign_pointer(vlan->taps[vlan->numvtaps], q);
124 sock_hold(&q->sk);
125
126 q->file = file;
127 q->queue_index = vlan->numvtaps;
128 q->enabled = true;
129 file->private_data = q;
130 list_add_tail(&q->next, &vlan->queue_list);
131
132 vlan->numvtaps++;
133 vlan->numqueues++;
134
135out:
136 rtnl_unlock();
137 return err;
138}
139
140static int macvtap_disable_queue(struct macvtap_queue *q)
141{
142 struct macvlan_dev *vlan;
143 struct macvtap_queue *nq;
144
145 ASSERT_RTNL();
146 if (!q->enabled)
147 return -EINVAL;
148
149 vlan = rtnl_dereference(q->vlan);
150
151 if (vlan) {
152 int index = q->queue_index;
153 BUG_ON(index >= vlan->numvtaps);
154 nq = rtnl_dereference(vlan->taps[vlan->numvtaps - 1]);
155 nq->queue_index = index;
156
157 rcu_assign_pointer(vlan->taps[index], nq);
158 RCU_INIT_POINTER(vlan->taps[vlan->numvtaps - 1], NULL);
159 q->enabled = false;
160
161 vlan->numvtaps--;
162 }
163
164 return 0;
165}
166
167
168
169
170
171
172
173
174
175static void macvtap_put_queue(struct macvtap_queue *q)
176{
177 struct macvlan_dev *vlan;
178
179 rtnl_lock();
180 vlan = rtnl_dereference(q->vlan);
181
182 if (vlan) {
183 if (q->enabled)
184 BUG_ON(macvtap_disable_queue(q));
185
186 vlan->numqueues--;
187 RCU_INIT_POINTER(q->vlan, NULL);
188 sock_put(&q->sk);
189 list_del_init(&q->next);
190 }
191
192 rtnl_unlock();
193
194 synchronize_rcu();
195 sock_put(&q->sk);
196}
197
198
199
200
201
202
203
204
205static struct macvtap_queue *macvtap_get_queue(struct net_device *dev,
206 struct sk_buff *skb)
207{
208 struct macvlan_dev *vlan = netdev_priv(dev);
209 struct macvtap_queue *tap = NULL;
210
211
212
213
214
215 int numvtaps = ACCESS_ONCE(vlan->numvtaps);
216 __u32 rxq;
217
218 if (!numvtaps)
219 goto out;
220
221
222 rxq = skb_get_rxhash(skb);
223 if (rxq) {
224 tap = rcu_dereference(vlan->taps[rxq % numvtaps]);
225 goto out;
226 }
227
228 if (likely(skb_rx_queue_recorded(skb))) {
229 rxq = skb_get_rx_queue(skb);
230
231 while (unlikely(rxq >= numvtaps))
232 rxq -= numvtaps;
233
234 tap = rcu_dereference(vlan->taps[rxq]);
235 goto out;
236 }
237
238 tap = rcu_dereference(vlan->taps[0]);
239out:
240 return tap;
241}
242
243
244
245
246
247
248static void macvtap_del_queues(struct net_device *dev)
249{
250 struct macvlan_dev *vlan = netdev_priv(dev);
251 struct macvtap_queue *q, *tmp, *qlist[MAX_MACVTAP_QUEUES];
252 int i, j = 0;
253
254 ASSERT_RTNL();
255 list_for_each_entry_safe(q, tmp, &vlan->queue_list, next) {
256 list_del_init(&q->next);
257 qlist[j++] = q;
258 RCU_INIT_POINTER(q->vlan, NULL);
259 if (q->enabled)
260 vlan->numvtaps--;
261 vlan->numqueues--;
262 }
263 for (i = 0; i < vlan->numvtaps; i++)
264 RCU_INIT_POINTER(vlan->taps[i], NULL);
265 BUG_ON(vlan->numvtaps);
266 BUG_ON(vlan->numqueues);
267
268 vlan->numvtaps = MAX_MACVTAP_QUEUES;
269
270 for (--j; j >= 0; j--)
271 sock_put(&qlist[j]->sk);
272}
273
274
275
276
277
278
279static int macvtap_forward(struct net_device *dev, struct sk_buff *skb)
280{
281 struct macvlan_dev *vlan = netdev_priv(dev);
282 struct macvtap_queue *q = macvtap_get_queue(dev, skb);
283 netdev_features_t features = TAP_FEATURES;
284
285 if (!q)
286 goto drop;
287
288 if (skb_queue_len(&q->sk.sk_receive_queue) >= dev->tx_queue_len)
289 goto drop;
290
291 skb->dev = dev;
292
293
294
295
296 if (q->flags & IFF_VNET_HDR)
297 features |= vlan->tap_features;
298 if (netif_needs_gso(skb, features)) {
299 struct sk_buff *segs = __skb_gso_segment(skb, features, false);
300
301 if (IS_ERR(segs))
302 goto drop;
303
304 if (!segs) {
305 skb_queue_tail(&q->sk.sk_receive_queue, skb);
306 goto wake_up;
307 }
308
309 kfree_skb(skb);
310 while (segs) {
311 struct sk_buff *nskb = segs->next;
312
313 segs->next = NULL;
314 skb_queue_tail(&q->sk.sk_receive_queue, segs);
315 segs = nskb;
316 }
317 } else {
318 skb_queue_tail(&q->sk.sk_receive_queue, skb);
319 }
320
321wake_up:
322 wake_up_interruptible_poll(sk_sleep(&q->sk), POLLIN | POLLRDNORM | POLLRDBAND);
323 return NET_RX_SUCCESS;
324
325drop:
326 kfree_skb(skb);
327 return NET_RX_DROP;
328}
329
330
331
332
333
334
335static int macvtap_receive(struct sk_buff *skb)
336{
337 skb_push(skb, ETH_HLEN);
338 return macvtap_forward(skb->dev, skb);
339}
340
341static int macvtap_get_minor(struct macvlan_dev *vlan)
342{
343 int retval = -ENOMEM;
344
345 mutex_lock(&minor_lock);
346 retval = idr_alloc(&minor_idr, vlan, 1, MACVTAP_NUM_DEVS, GFP_KERNEL);
347 if (retval >= 0) {
348 vlan->minor = retval;
349 } else if (retval == -ENOSPC) {
350 printk(KERN_ERR "too many macvtap devices\n");
351 retval = -EINVAL;
352 }
353 mutex_unlock(&minor_lock);
354 return retval < 0 ? retval : 0;
355}
356
357static void macvtap_free_minor(struct macvlan_dev *vlan)
358{
359 mutex_lock(&minor_lock);
360 if (vlan->minor) {
361 idr_remove(&minor_idr, vlan->minor);
362 vlan->minor = 0;
363 }
364 mutex_unlock(&minor_lock);
365}
366
367static struct net_device *dev_get_by_macvtap_minor(int minor)
368{
369 struct net_device *dev = NULL;
370 struct macvlan_dev *vlan;
371
372 mutex_lock(&minor_lock);
373 vlan = idr_find(&minor_idr, minor);
374 if (vlan) {
375 dev = vlan->dev;
376 dev_hold(dev);
377 }
378 mutex_unlock(&minor_lock);
379 return dev;
380}
381
382static int macvtap_newlink(struct net *src_net,
383 struct net_device *dev,
384 struct nlattr *tb[],
385 struct nlattr *data[])
386{
387 struct macvlan_dev *vlan = netdev_priv(dev);
388 INIT_LIST_HEAD(&vlan->queue_list);
389
390
391
392
393 vlan->tap_features = TUN_OFFLOADS;
394
395
396
397
398 return macvlan_common_newlink(src_net, dev, tb, data,
399 macvtap_receive, macvtap_forward);
400}
401
402static void macvtap_dellink(struct net_device *dev,
403 struct list_head *head)
404{
405 macvtap_del_queues(dev);
406 macvlan_dellink(dev, head);
407}
408
409static void macvtap_setup(struct net_device *dev)
410{
411 macvlan_common_setup(dev);
412 dev->tx_queue_len = TUN_READQ_SIZE;
413}
414
415static struct rtnl_link_ops macvtap_link_ops __read_mostly = {
416 .kind = "macvtap",
417 .setup = macvtap_setup,
418 .newlink = macvtap_newlink,
419 .dellink = macvtap_dellink,
420};
421
422
423static void macvtap_sock_write_space(struct sock *sk)
424{
425 wait_queue_head_t *wqueue;
426
427 if (!sock_writeable(sk) ||
428 !test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags))
429 return;
430
431 wqueue = sk_sleep(sk);
432 if (wqueue && waitqueue_active(wqueue))
433 wake_up_interruptible_poll(wqueue, POLLOUT | POLLWRNORM | POLLWRBAND);
434}
435
436static void macvtap_sock_destruct(struct sock *sk)
437{
438 skb_queue_purge(&sk->sk_receive_queue);
439}
440
441static int macvtap_open(struct inode *inode, struct file *file)
442{
443 struct net *net = current->nsproxy->net_ns;
444 struct net_device *dev = dev_get_by_macvtap_minor(iminor(inode));
445 struct macvtap_queue *q;
446 int err;
447
448 err = -ENODEV;
449 if (!dev)
450 goto out;
451
452 err = -ENOMEM;
453 q = (struct macvtap_queue *)sk_alloc(net, AF_UNSPEC, GFP_KERNEL,
454 &macvtap_proto);
455 if (!q)
456 goto out;
457
458 RCU_INIT_POINTER(q->sock.wq, &q->wq);
459 init_waitqueue_head(&q->wq.wait);
460 q->sock.type = SOCK_RAW;
461 q->sock.state = SS_CONNECTED;
462 q->sock.file = file;
463 q->sock.ops = &macvtap_socket_ops;
464 sock_init_data(&q->sock, &q->sk);
465 q->sk.sk_write_space = macvtap_sock_write_space;
466 q->sk.sk_destruct = macvtap_sock_destruct;
467 q->flags = IFF_VNET_HDR | IFF_NO_PI | IFF_TAP;
468 q->vnet_hdr_sz = sizeof(struct virtio_net_hdr);
469
470
471
472
473
474
475
476
477 if ((dev->features & NETIF_F_HIGHDMA) && (dev->features & NETIF_F_SG))
478 sock_set_flag(&q->sk, SOCK_ZEROCOPY);
479
480 err = macvtap_set_queue(dev, file, q);
481 if (err)
482 sock_put(&q->sk);
483
484out:
485 if (dev)
486 dev_put(dev);
487
488 return err;
489}
490
491static int macvtap_release(struct inode *inode, struct file *file)
492{
493 struct macvtap_queue *q = file->private_data;
494 macvtap_put_queue(q);
495 return 0;
496}
497
498static unsigned int macvtap_poll(struct file *file, poll_table * wait)
499{
500 struct macvtap_queue *q = file->private_data;
501 unsigned int mask = POLLERR;
502
503 if (!q)
504 goto out;
505
506 mask = 0;
507 poll_wait(file, &q->wq.wait, wait);
508
509 if (!skb_queue_empty(&q->sk.sk_receive_queue))
510 mask |= POLLIN | POLLRDNORM;
511
512 if (sock_writeable(&q->sk) ||
513 (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &q->sock.flags) &&
514 sock_writeable(&q->sk)))
515 mask |= POLLOUT | POLLWRNORM;
516
517out:
518 return mask;
519}
520
521static inline struct sk_buff *macvtap_alloc_skb(struct sock *sk, size_t prepad,
522 size_t len, size_t linear,
523 int noblock, int *err)
524{
525 struct sk_buff *skb;
526
527
528 if (prepad + len < PAGE_SIZE || !linear)
529 linear = len;
530
531 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
532 err, 0);
533 if (!skb)
534 return NULL;
535
536 skb_reserve(skb, prepad);
537 skb_put(skb, linear);
538 skb->data_len = len - linear;
539 skb->len += len - linear;
540
541 return skb;
542}
543
544
545
546
547
548static int macvtap_skb_from_vnet_hdr(struct sk_buff *skb,
549 struct virtio_net_hdr *vnet_hdr)
550{
551 unsigned short gso_type = 0;
552 if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
553 switch (vnet_hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
554 case VIRTIO_NET_HDR_GSO_TCPV4:
555 gso_type = SKB_GSO_TCPV4;
556 break;
557 case VIRTIO_NET_HDR_GSO_TCPV6:
558 gso_type = SKB_GSO_TCPV6;
559 break;
560 case VIRTIO_NET_HDR_GSO_UDP:
561 gso_type = SKB_GSO_UDP;
562 break;
563 default:
564 return -EINVAL;
565 }
566
567 if (vnet_hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN)
568 gso_type |= SKB_GSO_TCP_ECN;
569
570 if (vnet_hdr->gso_size == 0)
571 return -EINVAL;
572 }
573
574 if (vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
575 if (!skb_partial_csum_set(skb, vnet_hdr->csum_start,
576 vnet_hdr->csum_offset))
577 return -EINVAL;
578 }
579
580 if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
581 skb_shinfo(skb)->gso_size = vnet_hdr->gso_size;
582 skb_shinfo(skb)->gso_type = gso_type;
583
584
585 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
586 skb_shinfo(skb)->gso_segs = 0;
587 }
588 return 0;
589}
590
591static int macvtap_skb_to_vnet_hdr(const struct sk_buff *skb,
592 struct virtio_net_hdr *vnet_hdr)
593{
594 memset(vnet_hdr, 0, sizeof(*vnet_hdr));
595
596 if (skb_is_gso(skb)) {
597 struct skb_shared_info *sinfo = skb_shinfo(skb);
598
599
600 vnet_hdr->hdr_len = skb_headlen(skb);
601 vnet_hdr->gso_size = sinfo->gso_size;
602 if (sinfo->gso_type & SKB_GSO_TCPV4)
603 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
604 else if (sinfo->gso_type & SKB_GSO_TCPV6)
605 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
606 else if (sinfo->gso_type & SKB_GSO_UDP)
607 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
608 else
609 BUG();
610 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
611 vnet_hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
612 } else
613 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
614
615 if (skb->ip_summed == CHECKSUM_PARTIAL) {
616 vnet_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
617 vnet_hdr->csum_start = skb_checksum_start_offset(skb);
618 vnet_hdr->csum_offset = skb->csum_offset;
619 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
620 vnet_hdr->flags = VIRTIO_NET_HDR_F_DATA_VALID;
621 }
622
623 return 0;
624}
625
626
627static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
628 const struct iovec *iv, unsigned long total_len,
629 size_t count, int noblock)
630{
631 struct sk_buff *skb;
632 struct macvlan_dev *vlan;
633 unsigned long len = total_len;
634 int err;
635 struct virtio_net_hdr vnet_hdr = { 0 };
636 int vnet_hdr_len = 0;
637 int copylen = 0;
638 bool zerocopy = false;
639 size_t linear;
640
641 if (q->flags & IFF_VNET_HDR) {
642 vnet_hdr_len = q->vnet_hdr_sz;
643
644 err = -EINVAL;
645 if (len < vnet_hdr_len)
646 goto err;
647 len -= vnet_hdr_len;
648
649 err = memcpy_fromiovecend((void *)&vnet_hdr, iv, 0,
650 sizeof(vnet_hdr));
651 if (err < 0)
652 goto err;
653 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
654 vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
655 vnet_hdr.hdr_len)
656 vnet_hdr.hdr_len = vnet_hdr.csum_start +
657 vnet_hdr.csum_offset + 2;
658 err = -EINVAL;
659 if (vnet_hdr.hdr_len > len)
660 goto err;
661 }
662
663 err = -EINVAL;
664 if (unlikely(len < ETH_HLEN))
665 goto err;
666
667 err = -EMSGSIZE;
668 if (unlikely(count > UIO_MAXIOV))
669 goto err;
670
671 if (m && m->msg_control && sock_flag(&q->sk, SOCK_ZEROCOPY)) {
672 copylen = vnet_hdr.hdr_len ? vnet_hdr.hdr_len : GOODCOPY_LEN;
673 linear = copylen;
674 if (iov_pages(iv, vnet_hdr_len + copylen, count)
675 <= MAX_SKB_FRAGS)
676 zerocopy = true;
677 }
678
679 if (!zerocopy) {
680 copylen = len;
681 linear = vnet_hdr.hdr_len;
682 }
683
684 skb = macvtap_alloc_skb(&q->sk, NET_IP_ALIGN, copylen,
685 linear, noblock, &err);
686 if (!skb)
687 goto err;
688
689 if (zerocopy)
690 err = zerocopy_sg_from_iovec(skb, iv, vnet_hdr_len, count);
691 else {
692 err = skb_copy_datagram_from_iovec(skb, 0, iv, vnet_hdr_len,
693 len);
694 if (!err && m && m->msg_control) {
695 struct ubuf_info *uarg = m->msg_control;
696 uarg->callback(uarg, false);
697 }
698 }
699
700 if (err)
701 goto err_kfree;
702
703 skb_set_network_header(skb, ETH_HLEN);
704 skb_reset_mac_header(skb);
705 skb->protocol = eth_hdr(skb)->h_proto;
706
707 if (vnet_hdr_len) {
708 err = macvtap_skb_from_vnet_hdr(skb, &vnet_hdr);
709 if (err)
710 goto err_kfree;
711 }
712
713 skb_probe_transport_header(skb, ETH_HLEN);
714
715 rcu_read_lock();
716 vlan = rcu_dereference(q->vlan);
717
718 if (zerocopy) {
719 skb_shinfo(skb)->destructor_arg = m->msg_control;
720 skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY;
721 skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG;
722 }
723 if (vlan) {
724 local_bh_disable();
725 macvlan_start_xmit(skb, vlan->dev);
726 local_bh_enable();
727 } else {
728 kfree_skb(skb);
729 }
730 rcu_read_unlock();
731
732 return total_len;
733
734err_kfree:
735 kfree_skb(skb);
736
737err:
738 rcu_read_lock();
739 vlan = rcu_dereference(q->vlan);
740 if (vlan)
741 vlan->dev->stats.tx_dropped++;
742 rcu_read_unlock();
743
744 return err;
745}
746
747static ssize_t macvtap_aio_write(struct kiocb *iocb, const struct iovec *iv,
748 unsigned long count, loff_t pos)
749{
750 struct file *file = iocb->ki_filp;
751 ssize_t result = -ENOLINK;
752 struct macvtap_queue *q = file->private_data;
753
754 result = macvtap_get_user(q, NULL, iv, iov_length(iv, count), count,
755 file->f_flags & O_NONBLOCK);
756 return result;
757}
758
759
760static ssize_t macvtap_put_user(struct macvtap_queue *q,
761 const struct sk_buff *skb,
762 const struct iovec *iv, int len)
763{
764 struct macvlan_dev *vlan;
765 int ret;
766 int vnet_hdr_len = 0;
767 int vlan_offset = 0;
768 int copied;
769
770 if (q->flags & IFF_VNET_HDR) {
771 struct virtio_net_hdr vnet_hdr;
772 vnet_hdr_len = q->vnet_hdr_sz;
773 if ((len -= vnet_hdr_len) < 0)
774 return -EINVAL;
775
776 ret = macvtap_skb_to_vnet_hdr(skb, &vnet_hdr);
777 if (ret)
778 return ret;
779
780 if (memcpy_toiovecend(iv, (void *)&vnet_hdr, 0, sizeof(vnet_hdr)))
781 return -EFAULT;
782 }
783 copied = vnet_hdr_len;
784
785 if (!vlan_tx_tag_present(skb))
786 len = min_t(int, skb->len, len);
787 else {
788 int copy;
789 struct {
790 __be16 h_vlan_proto;
791 __be16 h_vlan_TCI;
792 } veth;
793 veth.h_vlan_proto = skb->vlan_proto;
794 veth.h_vlan_TCI = htons(vlan_tx_tag_get(skb));
795
796 vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto);
797 len = min_t(int, skb->len + VLAN_HLEN, len);
798
799 copy = min_t(int, vlan_offset, len);
800 ret = skb_copy_datagram_const_iovec(skb, 0, iv, copied, copy);
801 len -= copy;
802 copied += copy;
803 if (ret || !len)
804 goto done;
805
806 copy = min_t(int, sizeof(veth), len);
807 ret = memcpy_toiovecend(iv, (void *)&veth, copied, copy);
808 len -= copy;
809 copied += copy;
810 if (ret || !len)
811 goto done;
812 }
813
814 ret = skb_copy_datagram_const_iovec(skb, vlan_offset, iv, copied, len);
815 copied += len;
816
817done:
818 rcu_read_lock();
819 vlan = rcu_dereference(q->vlan);
820 if (vlan) {
821 preempt_disable();
822 macvlan_count_rx(vlan, copied - vnet_hdr_len, ret == 0, 0);
823 preempt_enable();
824 }
825 rcu_read_unlock();
826
827 return ret ? ret : copied;
828}
829
830static ssize_t macvtap_do_read(struct macvtap_queue *q, struct kiocb *iocb,
831 const struct iovec *iv, unsigned long len,
832 int noblock)
833{
834 DEFINE_WAIT(wait);
835 struct sk_buff *skb;
836 ssize_t ret = 0;
837
838 while (len) {
839 if (!noblock)
840 prepare_to_wait(sk_sleep(&q->sk), &wait,
841 TASK_INTERRUPTIBLE);
842
843
844 skb = skb_dequeue(&q->sk.sk_receive_queue);
845 if (!skb) {
846 if (noblock) {
847 ret = -EAGAIN;
848 break;
849 }
850 if (signal_pending(current)) {
851 ret = -ERESTARTSYS;
852 break;
853 }
854
855 schedule();
856 continue;
857 }
858 ret = macvtap_put_user(q, skb, iv, len);
859 kfree_skb(skb);
860 break;
861 }
862
863 if (!noblock)
864 finish_wait(sk_sleep(&q->sk), &wait);
865 return ret;
866}
867
868static ssize_t macvtap_aio_read(struct kiocb *iocb, const struct iovec *iv,
869 unsigned long count, loff_t pos)
870{
871 struct file *file = iocb->ki_filp;
872 struct macvtap_queue *q = file->private_data;
873 ssize_t len, ret = 0;
874
875 len = iov_length(iv, count);
876 if (len < 0) {
877 ret = -EINVAL;
878 goto out;
879 }
880
881 ret = macvtap_do_read(q, iocb, iv, len, file->f_flags & O_NONBLOCK);
882 ret = min_t(ssize_t, ret, len);
883out:
884 return ret;
885}
886
887static struct macvlan_dev *macvtap_get_vlan(struct macvtap_queue *q)
888{
889 struct macvlan_dev *vlan;
890
891 ASSERT_RTNL();
892 vlan = rtnl_dereference(q->vlan);
893 if (vlan)
894 dev_hold(vlan->dev);
895
896 return vlan;
897}
898
899static void macvtap_put_vlan(struct macvlan_dev *vlan)
900{
901 dev_put(vlan->dev);
902}
903
904static int macvtap_ioctl_set_queue(struct file *file, unsigned int flags)
905{
906 struct macvtap_queue *q = file->private_data;
907 struct macvlan_dev *vlan;
908 int ret;
909
910 vlan = macvtap_get_vlan(q);
911 if (!vlan)
912 return -EINVAL;
913
914 if (flags & IFF_ATTACH_QUEUE)
915 ret = macvtap_enable_queue(vlan->dev, file, q);
916 else if (flags & IFF_DETACH_QUEUE)
917 ret = macvtap_disable_queue(q);
918 else
919 ret = -EINVAL;
920
921 macvtap_put_vlan(vlan);
922 return ret;
923}
924
925static int set_offload(struct macvtap_queue *q, unsigned long arg)
926{
927 struct macvlan_dev *vlan;
928 netdev_features_t features;
929 netdev_features_t feature_mask = 0;
930
931 vlan = rtnl_dereference(q->vlan);
932 if (!vlan)
933 return -ENOLINK;
934
935 features = vlan->dev->features;
936
937 if (arg & TUN_F_CSUM) {
938 feature_mask = NETIF_F_HW_CSUM;
939
940 if (arg & (TUN_F_TSO4 | TUN_F_TSO6)) {
941 if (arg & TUN_F_TSO_ECN)
942 feature_mask |= NETIF_F_TSO_ECN;
943 if (arg & TUN_F_TSO4)
944 feature_mask |= NETIF_F_TSO;
945 if (arg & TUN_F_TSO6)
946 feature_mask |= NETIF_F_TSO6;
947 }
948
949 if (arg & TUN_F_UFO)
950 feature_mask |= NETIF_F_UFO;
951 }
952
953
954
955
956
957
958
959
960
961 if (feature_mask & (NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_UFO))
962 features |= RX_OFFLOADS;
963 else
964 features &= ~RX_OFFLOADS;
965
966
967
968
969 vlan->tap_features = feature_mask;
970 vlan->set_features = features;
971 netdev_update_features(vlan->dev);
972
973 return 0;
974}
975
976
977
978
979static long macvtap_ioctl(struct file *file, unsigned int cmd,
980 unsigned long arg)
981{
982 struct macvtap_queue *q = file->private_data;
983 struct macvlan_dev *vlan;
984 void __user *argp = (void __user *)arg;
985 struct ifreq __user *ifr = argp;
986 unsigned int __user *up = argp;
987 unsigned int u;
988 int __user *sp = argp;
989 int s;
990 int ret;
991
992 switch (cmd) {
993 case TUNSETIFF:
994
995 if (get_user(u, &ifr->ifr_flags))
996 return -EFAULT;
997
998 ret = 0;
999 if ((u & ~(IFF_VNET_HDR | IFF_MULTI_QUEUE)) !=
1000 (IFF_NO_PI | IFF_TAP))
1001 ret = -EINVAL;
1002 else
1003 q->flags = u;
1004
1005 return ret;
1006
1007 case TUNGETIFF:
1008 rtnl_lock();
1009 vlan = macvtap_get_vlan(q);
1010 if (!vlan) {
1011 rtnl_unlock();
1012 return -ENOLINK;
1013 }
1014
1015 ret = 0;
1016 if (copy_to_user(&ifr->ifr_name, vlan->dev->name, IFNAMSIZ) ||
1017 put_user(q->flags, &ifr->ifr_flags))
1018 ret = -EFAULT;
1019 macvtap_put_vlan(vlan);
1020 rtnl_unlock();
1021 return ret;
1022
1023 case TUNSETQUEUE:
1024 if (get_user(u, &ifr->ifr_flags))
1025 return -EFAULT;
1026 rtnl_lock();
1027 ret = macvtap_ioctl_set_queue(file, u);
1028 rtnl_unlock();
1029 return ret;
1030
1031 case TUNGETFEATURES:
1032 if (put_user(IFF_TAP | IFF_NO_PI | IFF_VNET_HDR |
1033 IFF_MULTI_QUEUE, up))
1034 return -EFAULT;
1035 return 0;
1036
1037 case TUNSETSNDBUF:
1038 if (get_user(u, up))
1039 return -EFAULT;
1040
1041 q->sk.sk_sndbuf = u;
1042 return 0;
1043
1044 case TUNGETVNETHDRSZ:
1045 s = q->vnet_hdr_sz;
1046 if (put_user(s, sp))
1047 return -EFAULT;
1048 return 0;
1049
1050 case TUNSETVNETHDRSZ:
1051 if (get_user(s, sp))
1052 return -EFAULT;
1053 if (s < (int)sizeof(struct virtio_net_hdr))
1054 return -EINVAL;
1055
1056 q->vnet_hdr_sz = s;
1057 return 0;
1058
1059 case TUNSETOFFLOAD:
1060
1061 if (arg & ~(TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6 |
1062 TUN_F_TSO_ECN | TUN_F_UFO))
1063 return -EINVAL;
1064
1065 rtnl_lock();
1066 ret = set_offload(q, arg);
1067 rtnl_unlock();
1068 return ret;
1069
1070 default:
1071 return -EINVAL;
1072 }
1073}
1074
1075#ifdef CONFIG_COMPAT
1076static long macvtap_compat_ioctl(struct file *file, unsigned int cmd,
1077 unsigned long arg)
1078{
1079 return macvtap_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
1080}
1081#endif
1082
1083static const struct file_operations macvtap_fops = {
1084 .owner = THIS_MODULE,
1085 .open = macvtap_open,
1086 .release = macvtap_release,
1087 .aio_read = macvtap_aio_read,
1088 .aio_write = macvtap_aio_write,
1089 .poll = macvtap_poll,
1090 .llseek = no_llseek,
1091 .unlocked_ioctl = macvtap_ioctl,
1092#ifdef CONFIG_COMPAT
1093 .compat_ioctl = macvtap_compat_ioctl,
1094#endif
1095};
1096
1097static int macvtap_sendmsg(struct kiocb *iocb, struct socket *sock,
1098 struct msghdr *m, size_t total_len)
1099{
1100 struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock);
1101 return macvtap_get_user(q, m, m->msg_iov, total_len, m->msg_iovlen,
1102 m->msg_flags & MSG_DONTWAIT);
1103}
1104
1105static int macvtap_recvmsg(struct kiocb *iocb, struct socket *sock,
1106 struct msghdr *m, size_t total_len,
1107 int flags)
1108{
1109 struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock);
1110 int ret;
1111 if (flags & ~(MSG_DONTWAIT|MSG_TRUNC))
1112 return -EINVAL;
1113 ret = macvtap_do_read(q, iocb, m->msg_iov, total_len,
1114 flags & MSG_DONTWAIT);
1115 if (ret > total_len) {
1116 m->msg_flags |= MSG_TRUNC;
1117 ret = flags & MSG_TRUNC ? ret : total_len;
1118 }
1119 return ret;
1120}
1121
1122
1123static const struct proto_ops macvtap_socket_ops = {
1124 .sendmsg = macvtap_sendmsg,
1125 .recvmsg = macvtap_recvmsg,
1126};
1127
1128
1129
1130
1131
1132struct socket *macvtap_get_socket(struct file *file)
1133{
1134 struct macvtap_queue *q;
1135 if (file->f_op != &macvtap_fops)
1136 return ERR_PTR(-EINVAL);
1137 q = file->private_data;
1138 if (!q)
1139 return ERR_PTR(-EBADFD);
1140 return &q->sock;
1141}
1142EXPORT_SYMBOL_GPL(macvtap_get_socket);
1143
1144static int macvtap_device_event(struct notifier_block *unused,
1145 unsigned long event, void *ptr)
1146{
1147 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1148 struct macvlan_dev *vlan;
1149 struct device *classdev;
1150 dev_t devt;
1151 int err;
1152
1153 if (dev->rtnl_link_ops != &macvtap_link_ops)
1154 return NOTIFY_DONE;
1155
1156 vlan = netdev_priv(dev);
1157
1158 switch (event) {
1159 case NETDEV_REGISTER:
1160
1161
1162
1163
1164 err = macvtap_get_minor(vlan);
1165 if (err)
1166 return notifier_from_errno(err);
1167
1168 devt = MKDEV(MAJOR(macvtap_major), vlan->minor);
1169 classdev = device_create(macvtap_class, &dev->dev, devt,
1170 dev, "tap%d", dev->ifindex);
1171 if (IS_ERR(classdev)) {
1172 macvtap_free_minor(vlan);
1173 return notifier_from_errno(PTR_ERR(classdev));
1174 }
1175 break;
1176 case NETDEV_UNREGISTER:
1177 devt = MKDEV(MAJOR(macvtap_major), vlan->minor);
1178 device_destroy(macvtap_class, devt);
1179 macvtap_free_minor(vlan);
1180 break;
1181 }
1182
1183 return NOTIFY_DONE;
1184}
1185
1186static struct notifier_block macvtap_notifier_block __read_mostly = {
1187 .notifier_call = macvtap_device_event,
1188};
1189
1190static int macvtap_init(void)
1191{
1192 int err;
1193
1194 err = alloc_chrdev_region(&macvtap_major, 0,
1195 MACVTAP_NUM_DEVS, "macvtap");
1196 if (err)
1197 goto out1;
1198
1199 cdev_init(&macvtap_cdev, &macvtap_fops);
1200 err = cdev_add(&macvtap_cdev, macvtap_major, MACVTAP_NUM_DEVS);
1201 if (err)
1202 goto out2;
1203
1204 macvtap_class = class_create(THIS_MODULE, "macvtap");
1205 if (IS_ERR(macvtap_class)) {
1206 err = PTR_ERR(macvtap_class);
1207 goto out3;
1208 }
1209
1210 err = register_netdevice_notifier(&macvtap_notifier_block);
1211 if (err)
1212 goto out4;
1213
1214 err = macvlan_link_register(&macvtap_link_ops);
1215 if (err)
1216 goto out5;
1217
1218 return 0;
1219
1220out5:
1221 unregister_netdevice_notifier(&macvtap_notifier_block);
1222out4:
1223 class_unregister(macvtap_class);
1224out3:
1225 cdev_del(&macvtap_cdev);
1226out2:
1227 unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
1228out1:
1229 return err;
1230}
1231module_init(macvtap_init);
1232
1233static void macvtap_exit(void)
1234{
1235 rtnl_link_unregister(&macvtap_link_ops);
1236 unregister_netdevice_notifier(&macvtap_notifier_block);
1237 class_unregister(macvtap_class);
1238 cdev_del(&macvtap_cdev);
1239 unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
1240}
1241module_exit(macvtap_exit);
1242
1243MODULE_ALIAS_RTNL_LINK("macvtap");
1244MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
1245MODULE_LICENSE("GPL");
1246