1 #include <linux/etherdevice.h>
2 #include <linux/if_macvlan.h>
3 #include <linux/interrupt.h>
4 #include <linux/nsproxy.h>
5 #include <linux/compat.h>
6 #include <linux/if_tun.h>
7 #include <linux/module.h>
8 #include <linux/skbuff.h>
9 #include <linux/cache.h>
10 #include <linux/sched.h>
11 #include <linux/types.h>
12 #include <linux/slab.h>
13 #include <linux/init.h>
14 #include <linux/wait.h>
15 #include <linux/cdev.h>
18 #include <net/net_namespace.h>
19 #include <net/rtnetlink.h>
21 #include <linux/virtio_net.h>
24 * A macvtap queue is the central object of this driver, it connects
25 * an open character device to a macvlan interface. There can be
26 * multiple queues on one interface, which map back to queues
27 * implemented in hardware on the underlying device.
29 * macvtap_proto is used to allocate queues through the sock allocation
32 * TODO: multiqueue support is currently not implemented, even though
33 * macvtap is basically prepared for that. We will need to add this
34 * here as well as in virtio-net and qemu to get line rate on 10gbit
35 * adapters from a guest.
37 struct macvtap_queue {
42 struct macvlan_dev __rcu *vlan;
47 static struct proto macvtap_proto = {
50 .obj_size = sizeof (struct macvtap_queue),
54 * Minor number matches netdev->ifindex, so need a potentially
55 * large value. This also makes it possible to split the
56 * tap functionality out again in the future by offering it
57 * from other drivers besides macvtap. As long as every device
58 * only has one tap, the interface numbers assure that the
59 * device nodes are unique.
61 static dev_t macvtap_major;
62 #define MACVTAP_NUM_DEVS 65536
63 #define GOODCOPY_LEN 128
64 static struct class *macvtap_class;
65 static struct cdev macvtap_cdev;
67 static const struct proto_ops macvtap_socket_ops;
71 * The macvtap_queue and the macvlan_dev are loosely coupled, the
72 * pointers from one to the other can only be read while rcu_read_lock
73 * or macvtap_lock is held.
75 * Both the file and the macvlan_dev hold a reference on the macvtap_queue
76 * through sock_hold(&q->sk). When the macvlan_dev goes away first,
77 * q->vlan becomes inaccessible. When the files gets closed,
78 * macvtap_get_queue() fails.
80 * There may still be references to the struct sock inside of the
81 * queue from outbound SKBs, but these never reference back to the
82 * file or the dev. The data structure is freed through __sk_free
83 * when both our references and any pending SKBs are gone.
85 static DEFINE_SPINLOCK(macvtap_lock);
88 * get_slot: return a [unused/occupied] slot in vlan->taps[]:
89 * - if 'q' is NULL, return the first empty slot;
90 * - otherwise, return the slot this pointer occupies.
92 static int get_slot(struct macvlan_dev *vlan, struct macvtap_queue *q)
96 for (i = 0; i < MAX_MACVTAP_QUEUES; i++) {
97 if (rcu_dereference(vlan->taps[i]) == q)
101 /* Should never happen */
105 static int macvtap_set_queue(struct net_device *dev, struct file *file,
106 struct macvtap_queue *q)
108 struct macvlan_dev *vlan = netdev_priv(dev);
112 spin_lock(&macvtap_lock);
113 if (vlan->numvtaps == MAX_MACVTAP_QUEUES)
117 index = get_slot(vlan, NULL);
118 rcu_assign_pointer(q->vlan, vlan);
119 rcu_assign_pointer(vlan->taps[index], q);
123 file->private_data = q;
128 spin_unlock(&macvtap_lock);
133 * The file owning the queue got closed, give up both
134 * the reference that the files holds as well as the
135 * one from the macvlan_dev if that still exists.
137 * Using the spinlock makes sure that we don't get
138 * to the queue again after destroying it.
140 static void macvtap_put_queue(struct macvtap_queue *q)
142 struct macvlan_dev *vlan;
144 spin_lock(&macvtap_lock);
145 vlan = rcu_dereference_protected(q->vlan,
146 lockdep_is_held(&macvtap_lock));
148 int index = get_slot(vlan, q);
150 rcu_assign_pointer(vlan->taps[index], NULL);
151 rcu_assign_pointer(q->vlan, NULL);
156 spin_unlock(&macvtap_lock);
163 * Select a queue based on the rxq of the device on which this packet
164 * arrived. If the incoming device is not mq, calculate a flow hash
165 * to select a queue. If all fails, find the first available queue.
166 * Cache vlan->numvtaps since it can become zero during the execution
169 static struct macvtap_queue *macvtap_get_queue(struct net_device *dev,
172 struct macvlan_dev *vlan = netdev_priv(dev);
173 struct macvtap_queue *tap = NULL;
174 int numvtaps = vlan->numvtaps;
180 if (likely(skb_rx_queue_recorded(skb))) {
181 rxq = skb_get_rx_queue(skb);
183 while (unlikely(rxq >= numvtaps))
186 tap = rcu_dereference(vlan->taps[rxq]);
191 /* Check if we can use flow to select a queue */
192 rxq = skb_get_rxhash(skb);
194 tap = rcu_dereference(vlan->taps[rxq % numvtaps]);
199 /* Everything failed - find first available queue */
200 for (rxq = 0; rxq < MAX_MACVTAP_QUEUES; rxq++) {
201 tap = rcu_dereference(vlan->taps[rxq]);
211 * The net_device is going away, give up the reference
212 * that it holds on all queues and safely set the pointer
213 * from the queues to NULL.
215 static void macvtap_del_queues(struct net_device *dev)
217 struct macvlan_dev *vlan = netdev_priv(dev);
218 struct macvtap_queue *q, *qlist[MAX_MACVTAP_QUEUES];
221 /* macvtap_put_queue can free some slots, so go through all slots */
222 spin_lock(&macvtap_lock);
223 for (i = 0; i < MAX_MACVTAP_QUEUES && vlan->numvtaps; i++) {
224 q = rcu_dereference_protected(vlan->taps[i],
225 lockdep_is_held(&macvtap_lock));
228 rcu_assign_pointer(vlan->taps[i], NULL);
229 rcu_assign_pointer(q->vlan, NULL);
233 BUG_ON(vlan->numvtaps != 0);
234 spin_unlock(&macvtap_lock);
238 for (--j; j >= 0; j--)
239 sock_put(&qlist[j]->sk);
243 * Forward happens for data that gets sent from one macvlan
244 * endpoint to another one in bridge mode. We just take
245 * the skb and put it into the receive queue.
247 static int macvtap_forward(struct net_device *dev, struct sk_buff *skb)
249 struct macvtap_queue *q = macvtap_get_queue(dev, skb);
253 if (skb_queue_len(&q->sk.sk_receive_queue) >= dev->tx_queue_len)
256 skb_queue_tail(&q->sk.sk_receive_queue, skb);
257 wake_up_interruptible_poll(sk_sleep(&q->sk), POLLIN | POLLRDNORM | POLLRDBAND);
258 return NET_RX_SUCCESS;
266 * Receive is for data from the external interface (lowerdev),
267 * in case of macvtap, we can treat that the same way as
268 * forward, which macvlan cannot.
270 static int macvtap_receive(struct sk_buff *skb)
272 skb_push(skb, ETH_HLEN);
273 return macvtap_forward(skb->dev, skb);
276 static int macvtap_newlink(struct net *src_net,
277 struct net_device *dev,
279 struct nlattr *data[])
281 struct device *classdev;
285 err = macvlan_common_newlink(src_net, dev, tb, data,
286 macvtap_receive, macvtap_forward);
290 devt = MKDEV(MAJOR(macvtap_major), dev->ifindex);
292 classdev = device_create(macvtap_class, &dev->dev, devt,
293 dev, "tap%d", dev->ifindex);
294 if (IS_ERR(classdev)) {
295 err = PTR_ERR(classdev);
296 macvtap_del_queues(dev);
303 static void macvtap_dellink(struct net_device *dev,
304 struct list_head *head)
306 device_destroy(macvtap_class,
307 MKDEV(MAJOR(macvtap_major), dev->ifindex));
309 macvtap_del_queues(dev);
310 macvlan_dellink(dev, head);
313 static void macvtap_setup(struct net_device *dev)
315 macvlan_common_setup(dev);
316 dev->tx_queue_len = TUN_READQ_SIZE;
319 static struct rtnl_link_ops macvtap_link_ops __read_mostly = {
321 .setup = macvtap_setup,
322 .newlink = macvtap_newlink,
323 .dellink = macvtap_dellink,
327 static void macvtap_sock_write_space(struct sock *sk)
329 wait_queue_head_t *wqueue;
331 if (!sock_writeable(sk) ||
332 !test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags))
335 wqueue = sk_sleep(sk);
336 if (wqueue && waitqueue_active(wqueue))
337 wake_up_interruptible_poll(wqueue, POLLOUT | POLLWRNORM | POLLWRBAND);
340 static int macvtap_open(struct inode *inode, struct file *file)
342 struct net *net = current->nsproxy->net_ns;
343 struct net_device *dev = dev_get_by_index(net, iminor(inode));
344 struct macvlan_dev *vlan = netdev_priv(dev);
345 struct macvtap_queue *q;
352 /* check if this is a macvtap device */
354 if (dev->rtnl_link_ops != &macvtap_link_ops)
358 q = (struct macvtap_queue *)sk_alloc(net, AF_UNSPEC, GFP_KERNEL,
364 init_waitqueue_head(&q->wq.wait);
365 q->sock.type = SOCK_RAW;
366 q->sock.state = SS_CONNECTED;
368 q->sock.ops = &macvtap_socket_ops;
369 sock_init_data(&q->sock, &q->sk);
370 q->sk.sk_write_space = macvtap_sock_write_space;
371 q->flags = IFF_VNET_HDR | IFF_NO_PI | IFF_TAP;
372 q->vnet_hdr_sz = sizeof(struct virtio_net_hdr);
375 * so far only KVM virtio_net uses macvtap, enable zero copy between
376 * guest kernel and host kernel when lower device supports zerocopy
379 if ((vlan->lowerdev->features & NETIF_F_HIGHDMA) &&
380 (vlan->lowerdev->features & NETIF_F_SG))
381 sock_set_flag(&q->sk, SOCK_ZEROCOPY);
384 err = macvtap_set_queue(dev, file, q);
395 static int macvtap_release(struct inode *inode, struct file *file)
397 struct macvtap_queue *q = file->private_data;
398 macvtap_put_queue(q);
402 static unsigned int macvtap_poll(struct file *file, poll_table * wait)
404 struct macvtap_queue *q = file->private_data;
405 unsigned int mask = POLLERR;
411 poll_wait(file, &q->wq.wait, wait);
413 if (!skb_queue_empty(&q->sk.sk_receive_queue))
414 mask |= POLLIN | POLLRDNORM;
416 if (sock_writeable(&q->sk) ||
417 (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &q->sock.flags) &&
418 sock_writeable(&q->sk)))
419 mask |= POLLOUT | POLLWRNORM;
425 static inline struct sk_buff *macvtap_alloc_skb(struct sock *sk, size_t prepad,
426 size_t len, size_t linear,
427 int noblock, int *err)
431 /* Under a page? Don't bother with paged skb. */
432 if (prepad + len < PAGE_SIZE || !linear)
435 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
440 skb_reserve(skb, prepad);
441 skb_put(skb, linear);
442 skb->data_len = len - linear;
443 skb->len += len - linear;
448 /* set skb frags from iovec, this can move to core network code for reuse */
449 static int zerocopy_sg_from_iovec(struct sk_buff *skb, const struct iovec *from,
450 int offset, size_t count)
452 int len = iov_length(from, count) - offset;
453 int copy = skb_headlen(skb);
454 int size, offset1 = 0;
458 /* Skip over from offset */
459 while (count && (offset >= from->iov_len)) {
460 offset -= from->iov_len;
465 /* copy up to skb headlen */
466 while (count && (copy > 0)) {
467 size = min_t(unsigned int, copy, from->iov_len - offset);
468 if (copy_from_user(skb->data + offset1, from->iov_base + offset,
484 struct page *page[MAX_SKB_FRAGS];
488 len = from->iov_len - offset1;
494 base = (unsigned long)from->iov_base + offset1;
495 size = ((base & ~PAGE_MASK) + len + ~PAGE_MASK) >> PAGE_SHIFT;
496 num_pages = get_user_pages_fast(base, size, 0, &page[i]);
497 if ((num_pages != size) ||
498 (num_pages > MAX_SKB_FRAGS - skb_shinfo(skb)->nr_frags))
499 /* put_page is in skb free */
501 skb->data_len += len;
503 skb->truesize += len;
504 atomic_add(len, &skb->sk->sk_wmem_alloc);
506 f = &skb_shinfo(skb)->frags[i];
508 f->page_offset = base & ~PAGE_MASK;
509 f->size = min_t(int, len, PAGE_SIZE - f->page_offset);
510 skb_shinfo(skb)->nr_frags++;
511 /* increase sk_wmem_alloc */
523 * macvtap_skb_from_vnet_hdr and macvtap_skb_to_vnet_hdr should
524 * be shared with the tun/tap driver.
526 static int macvtap_skb_from_vnet_hdr(struct sk_buff *skb,
527 struct virtio_net_hdr *vnet_hdr)
529 unsigned short gso_type = 0;
530 if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
531 switch (vnet_hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
532 case VIRTIO_NET_HDR_GSO_TCPV4:
533 gso_type = SKB_GSO_TCPV4;
535 case VIRTIO_NET_HDR_GSO_TCPV6:
536 gso_type = SKB_GSO_TCPV6;
538 case VIRTIO_NET_HDR_GSO_UDP:
539 gso_type = SKB_GSO_UDP;
545 if (vnet_hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN)
546 gso_type |= SKB_GSO_TCP_ECN;
548 if (vnet_hdr->gso_size == 0)
552 if (vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
553 if (!skb_partial_csum_set(skb, vnet_hdr->csum_start,
554 vnet_hdr->csum_offset))
558 if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
559 skb_shinfo(skb)->gso_size = vnet_hdr->gso_size;
560 skb_shinfo(skb)->gso_type = gso_type;
562 /* Header must be checked, and gso_segs computed. */
563 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
564 skb_shinfo(skb)->gso_segs = 0;
569 static int macvtap_skb_to_vnet_hdr(const struct sk_buff *skb,
570 struct virtio_net_hdr *vnet_hdr)
572 memset(vnet_hdr, 0, sizeof(*vnet_hdr));
574 if (skb_is_gso(skb)) {
575 struct skb_shared_info *sinfo = skb_shinfo(skb);
577 /* This is a hint as to how much should be linear. */
578 vnet_hdr->hdr_len = skb_headlen(skb);
579 vnet_hdr->gso_size = sinfo->gso_size;
580 if (sinfo->gso_type & SKB_GSO_TCPV4)
581 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
582 else if (sinfo->gso_type & SKB_GSO_TCPV6)
583 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
584 else if (sinfo->gso_type & SKB_GSO_UDP)
585 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
588 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
589 vnet_hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
591 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
593 if (skb->ip_summed == CHECKSUM_PARTIAL) {
594 vnet_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
595 vnet_hdr->csum_start = skb_checksum_start_offset(skb);
596 vnet_hdr->csum_offset = skb->csum_offset;
597 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
598 vnet_hdr->flags = VIRTIO_NET_HDR_F_DATA_VALID;
599 } /* else everything is zero */
605 /* Get packet from user space buffer */
606 static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
607 const struct iovec *iv, unsigned long total_len,
608 size_t count, int noblock)
611 struct macvlan_dev *vlan;
612 unsigned long len = total_len;
614 struct virtio_net_hdr vnet_hdr = { 0 };
615 int vnet_hdr_len = 0;
617 bool zerocopy = false;
619 if (q->flags & IFF_VNET_HDR) {
620 vnet_hdr_len = q->vnet_hdr_sz;
623 if (len < vnet_hdr_len)
627 err = memcpy_fromiovecend((void *)&vnet_hdr, iv, 0,
631 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
632 vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
634 vnet_hdr.hdr_len = vnet_hdr.csum_start +
635 vnet_hdr.csum_offset + 2;
637 if (vnet_hdr.hdr_len > len)
642 if (unlikely(len < ETH_HLEN))
645 if (m && m->msg_control && sock_flag(&q->sk, SOCK_ZEROCOPY))
649 /* There are 256 bytes to be copied in skb, so there is enough
650 * room for skb expand head in case it is used.
651 * The rest buffer is mapped from userspace.
653 copylen = vnet_hdr.hdr_len;
655 copylen = GOODCOPY_LEN;
659 skb = macvtap_alloc_skb(&q->sk, NET_IP_ALIGN, copylen,
660 vnet_hdr.hdr_len, noblock, &err);
665 err = zerocopy_sg_from_iovec(skb, iv, vnet_hdr_len, count);
666 skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY;
668 err = skb_copy_datagram_from_iovec(skb, 0, iv, vnet_hdr_len,
673 skb_set_network_header(skb, ETH_HLEN);
674 skb_reset_mac_header(skb);
675 skb->protocol = eth_hdr(skb)->h_proto;
678 err = macvtap_skb_from_vnet_hdr(skb, &vnet_hdr);
684 vlan = rcu_dereference_bh(q->vlan);
685 /* copy skb_ubuf_info for callback when skb has no error */
687 skb_shinfo(skb)->destructor_arg = m->msg_control;
689 macvlan_start_xmit(skb, vlan->dev);
692 rcu_read_unlock_bh();
701 vlan = rcu_dereference_bh(q->vlan);
703 vlan->dev->stats.tx_dropped++;
704 rcu_read_unlock_bh();
709 static ssize_t macvtap_aio_write(struct kiocb *iocb, const struct iovec *iv,
710 unsigned long count, loff_t pos)
712 struct file *file = iocb->ki_filp;
713 ssize_t result = -ENOLINK;
714 struct macvtap_queue *q = file->private_data;
716 result = macvtap_get_user(q, NULL, iv, iov_length(iv, count), count,
717 file->f_flags & O_NONBLOCK);
721 /* Put packet to the user space buffer */
722 static ssize_t macvtap_put_user(struct macvtap_queue *q,
723 const struct sk_buff *skb,
724 const struct iovec *iv, int len)
726 struct macvlan_dev *vlan;
728 int vnet_hdr_len = 0;
730 if (q->flags & IFF_VNET_HDR) {
731 struct virtio_net_hdr vnet_hdr;
732 vnet_hdr_len = q->vnet_hdr_sz;
733 if ((len -= vnet_hdr_len) < 0)
736 ret = macvtap_skb_to_vnet_hdr(skb, &vnet_hdr);
740 if (memcpy_toiovecend(iv, (void *)&vnet_hdr, 0, sizeof(vnet_hdr)))
744 len = min_t(int, skb->len, len);
746 ret = skb_copy_datagram_const_iovec(skb, 0, iv, vnet_hdr_len, len);
749 vlan = rcu_dereference_bh(q->vlan);
751 macvlan_count_rx(vlan, len, ret == 0, 0);
752 rcu_read_unlock_bh();
754 return ret ? ret : (len + vnet_hdr_len);
757 static ssize_t macvtap_do_read(struct macvtap_queue *q, struct kiocb *iocb,
758 const struct iovec *iv, unsigned long len,
761 DECLARE_WAITQUEUE(wait, current);
765 add_wait_queue(sk_sleep(&q->sk), &wait);
767 current->state = TASK_INTERRUPTIBLE;
769 /* Read frames from the queue */
770 skb = skb_dequeue(&q->sk.sk_receive_queue);
776 if (signal_pending(current)) {
780 /* Nothing to read, let's sleep */
784 ret = macvtap_put_user(q, skb, iv, len);
789 current->state = TASK_RUNNING;
790 remove_wait_queue(sk_sleep(&q->sk), &wait);
794 static ssize_t macvtap_aio_read(struct kiocb *iocb, const struct iovec *iv,
795 unsigned long count, loff_t pos)
797 struct file *file = iocb->ki_filp;
798 struct macvtap_queue *q = file->private_data;
799 ssize_t len, ret = 0;
801 len = iov_length(iv, count);
807 ret = macvtap_do_read(q, iocb, iv, len, file->f_flags & O_NONBLOCK);
808 ret = min_t(ssize_t, ret, len); /* XXX copied from tun.c. Why? */
814 * provide compatibility with generic tun/tap interface
816 static long macvtap_ioctl(struct file *file, unsigned int cmd,
819 struct macvtap_queue *q = file->private_data;
820 struct macvlan_dev *vlan;
821 void __user *argp = (void __user *)arg;
822 struct ifreq __user *ifr = argp;
823 unsigned int __user *up = argp;
825 int __user *sp = argp;
831 /* ignore the name, just look at flags */
832 if (get_user(u, &ifr->ifr_flags))
836 if ((u & ~IFF_VNET_HDR) != (IFF_NO_PI | IFF_TAP))
845 vlan = rcu_dereference_bh(q->vlan);
848 rcu_read_unlock_bh();
854 if (copy_to_user(&ifr->ifr_name, vlan->dev->name, IFNAMSIZ) ||
855 put_user(q->flags, &ifr->ifr_flags))
861 if (put_user(IFF_TAP | IFF_NO_PI | IFF_VNET_HDR, up))
872 case TUNGETVNETHDRSZ:
878 case TUNSETVNETHDRSZ:
881 if (s < (int)sizeof(struct virtio_net_hdr))
888 /* let the user check for future flags */
889 if (arg & ~(TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6 |
890 TUN_F_TSO_ECN | TUN_F_UFO))
893 /* TODO: only accept frames with the features that
894 got enabled for forwarded frames */
895 if (!(q->flags & IFF_VNET_HDR))
905 static long macvtap_compat_ioctl(struct file *file, unsigned int cmd,
908 return macvtap_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
912 static const struct file_operations macvtap_fops = {
913 .owner = THIS_MODULE,
914 .open = macvtap_open,
915 .release = macvtap_release,
916 .aio_read = macvtap_aio_read,
917 .aio_write = macvtap_aio_write,
918 .poll = macvtap_poll,
920 .unlocked_ioctl = macvtap_ioctl,
922 .compat_ioctl = macvtap_compat_ioctl,
926 static int macvtap_sendmsg(struct kiocb *iocb, struct socket *sock,
927 struct msghdr *m, size_t total_len)
929 struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock);
930 return macvtap_get_user(q, m, m->msg_iov, total_len, m->msg_iovlen,
931 m->msg_flags & MSG_DONTWAIT);
934 static int macvtap_recvmsg(struct kiocb *iocb, struct socket *sock,
935 struct msghdr *m, size_t total_len,
938 struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock);
940 if (flags & ~(MSG_DONTWAIT|MSG_TRUNC))
942 ret = macvtap_do_read(q, iocb, m->msg_iov, total_len,
943 flags & MSG_DONTWAIT);
944 if (ret > total_len) {
945 m->msg_flags |= MSG_TRUNC;
946 ret = flags & MSG_TRUNC ? ret : total_len;
951 /* Ops structure to mimic raw sockets with tun */
952 static const struct proto_ops macvtap_socket_ops = {
953 .sendmsg = macvtap_sendmsg,
954 .recvmsg = macvtap_recvmsg,
957 /* Get an underlying socket object from tun file. Returns error unless file is
958 * attached to a device. The returned object works like a packet socket, it
959 * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for
960 * holding a reference to the file for as long as the socket is in use. */
961 struct socket *macvtap_get_socket(struct file *file)
963 struct macvtap_queue *q;
964 if (file->f_op != &macvtap_fops)
965 return ERR_PTR(-EINVAL);
966 q = file->private_data;
968 return ERR_PTR(-EBADFD);
971 EXPORT_SYMBOL_GPL(macvtap_get_socket);
973 static int macvtap_init(void)
977 err = alloc_chrdev_region(&macvtap_major, 0,
978 MACVTAP_NUM_DEVS, "macvtap");
982 cdev_init(&macvtap_cdev, &macvtap_fops);
983 err = cdev_add(&macvtap_cdev, macvtap_major, MACVTAP_NUM_DEVS);
987 macvtap_class = class_create(THIS_MODULE, "macvtap");
988 if (IS_ERR(macvtap_class)) {
989 err = PTR_ERR(macvtap_class);
993 err = macvlan_link_register(&macvtap_link_ops);
1000 class_unregister(macvtap_class);
1002 cdev_del(&macvtap_cdev);
1004 unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
1008 module_init(macvtap_init);
1010 static void macvtap_exit(void)
1012 rtnl_link_unregister(&macvtap_link_ops);
1013 class_unregister(macvtap_class);
1014 cdev_del(&macvtap_cdev);
1015 unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
1017 module_exit(macvtap_exit);
1019 MODULE_ALIAS_RTNL_LINK("macvtap");
1020 MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
1021 MODULE_LICENSE("GPL");