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>
20 #include <net/net_namespace.h>
21 #include <net/rtnetlink.h>
23 #include <linux/virtio_net.h>
26 * A macvtap queue is the central object of this driver, it connects
27 * an open character device to a macvlan interface. There can be
28 * multiple queues on one interface, which map back to queues
29 * implemented in hardware on the underlying device.
31 * macvtap_proto is used to allocate queues through the sock allocation
34 * TODO: multiqueue support is currently not implemented, even though
35 * macvtap is basically prepared for that. We will need to add this
36 * here as well as in virtio-net and qemu to get line rate on 10gbit
37 * adapters from a guest.
39 struct macvtap_queue {
44 struct macvlan_dev __rcu *vlan;
50 static struct proto macvtap_proto = {
53 .obj_size = sizeof (struct macvtap_queue),
57 * Variables for dealing with macvtaps device numbers.
59 static dev_t macvtap_major;
60 #define MACVTAP_NUM_DEVS (1U << MINORBITS)
61 static DEFINE_MUTEX(minor_lock);
62 static DEFINE_IDR(minor_idr);
64 #define GOODCOPY_LEN 128
65 static struct class *macvtap_class;
66 static struct cdev macvtap_cdev;
68 static const struct proto_ops macvtap_socket_ops;
72 * The macvtap_queue and the macvlan_dev are loosely coupled, the
73 * pointers from one to the other can only be read while rcu_read_lock
74 * or macvtap_lock is held.
76 * Both the file and the macvlan_dev hold a reference on the macvtap_queue
77 * through sock_hold(&q->sk). When the macvlan_dev goes away first,
78 * q->vlan becomes inaccessible. When the files gets closed,
79 * macvtap_get_queue() fails.
81 * There may still be references to the struct sock inside of the
82 * queue from outbound SKBs, but these never reference back to the
83 * file or the dev. The data structure is freed through __sk_free
84 * when both our references and any pending SKBs are gone.
86 static DEFINE_SPINLOCK(macvtap_lock);
88 static int macvtap_set_queue(struct net_device *dev, struct file *file,
89 struct macvtap_queue *q)
91 struct macvlan_dev *vlan = netdev_priv(dev);
94 spin_lock(&macvtap_lock);
95 if (vlan->numvtaps == MAX_MACVTAP_QUEUES)
99 rcu_assign_pointer(q->vlan, vlan);
100 rcu_assign_pointer(vlan->taps[vlan->numvtaps], q);
104 q->queue_index = vlan->numvtaps;
105 file->private_data = q;
110 spin_unlock(&macvtap_lock);
115 * The file owning the queue got closed, give up both
116 * the reference that the files holds as well as the
117 * one from the macvlan_dev if that still exists.
119 * Using the spinlock makes sure that we don't get
120 * to the queue again after destroying it.
122 static void macvtap_put_queue(struct macvtap_queue *q)
124 struct macvtap_queue *nq;
125 struct macvlan_dev *vlan;
127 spin_lock(&macvtap_lock);
128 vlan = rcu_dereference_protected(q->vlan,
129 lockdep_is_held(&macvtap_lock));
131 int index = q->queue_index;
132 BUG_ON(index >= vlan->numvtaps);
134 nq = rcu_dereference_protected(vlan->taps[vlan->numvtaps - 1],
135 lockdep_is_held(&macvtap_lock));
136 rcu_assign_pointer(vlan->taps[index], nq);
137 nq->queue_index = index;
139 RCU_INIT_POINTER(vlan->taps[vlan->numvtaps - 1], NULL);
140 RCU_INIT_POINTER(q->vlan, NULL);
145 spin_unlock(&macvtap_lock);
152 * Select a queue based on the rxq of the device on which this packet
153 * arrived. If the incoming device is not mq, calculate a flow hash
154 * to select a queue. If all fails, find the first available queue.
155 * Cache vlan->numvtaps since it can become zero during the execution
158 static struct macvtap_queue *macvtap_get_queue(struct net_device *dev,
161 struct macvlan_dev *vlan = netdev_priv(dev);
162 struct macvtap_queue *tap = NULL;
163 int numvtaps = ACCESS_ONCE(vlan->numvtaps);
169 /* Check if we can use flow to select a queue */
170 rxq = skb_get_rxhash(skb);
172 tap = rcu_dereference(vlan->taps[rxq % numvtaps]);
176 if (likely(skb_rx_queue_recorded(skb))) {
177 rxq = skb_get_rx_queue(skb);
179 while (unlikely(rxq >= numvtaps))
182 tap = rcu_dereference(vlan->taps[rxq]);
186 tap = rcu_dereference(vlan->taps[0]);
192 * The net_device is going away, give up the reference
193 * that it holds on all queues and safely set the pointer
194 * from the queues to NULL.
196 static void macvtap_del_queues(struct net_device *dev)
198 struct macvlan_dev *vlan = netdev_priv(dev);
199 struct macvtap_queue *q, *qlist[MAX_MACVTAP_QUEUES];
202 spin_lock(&macvtap_lock);
203 for (i = 0; i < vlan->numvtaps; i++) {
204 q = rcu_dereference_protected(vlan->taps[i],
205 lockdep_is_held(&macvtap_lock));
208 RCU_INIT_POINTER(vlan->taps[i], NULL);
209 RCU_INIT_POINTER(q->vlan, NULL);
211 /* guarantee that any future macvtap_set_queue will fail */
212 vlan->numvtaps = MAX_MACVTAP_QUEUES;
213 spin_unlock(&macvtap_lock);
217 for (--j; j >= 0; j--)
218 sock_put(&qlist[j]->sk);
222 * Forward happens for data that gets sent from one macvlan
223 * endpoint to another one in bridge mode. We just take
224 * the skb and put it into the receive queue.
226 static int macvtap_forward(struct net_device *dev, struct sk_buff *skb)
228 struct macvtap_queue *q = macvtap_get_queue(dev, skb);
232 if (skb_queue_len(&q->sk.sk_receive_queue) >= dev->tx_queue_len)
235 skb_queue_tail(&q->sk.sk_receive_queue, skb);
236 wake_up_interruptible_poll(sk_sleep(&q->sk), POLLIN | POLLRDNORM | POLLRDBAND);
237 return NET_RX_SUCCESS;
245 * Receive is for data from the external interface (lowerdev),
246 * in case of macvtap, we can treat that the same way as
247 * forward, which macvlan cannot.
249 static int macvtap_receive(struct sk_buff *skb)
251 skb_push(skb, ETH_HLEN);
252 return macvtap_forward(skb->dev, skb);
255 static int macvtap_get_minor(struct macvlan_dev *vlan)
257 int retval = -ENOMEM;
259 mutex_lock(&minor_lock);
260 retval = idr_alloc(&minor_idr, vlan, 1, MACVTAP_NUM_DEVS, GFP_KERNEL);
262 vlan->minor = retval;
263 } else if (retval == -ENOSPC) {
264 printk(KERN_ERR "too many macvtap devices\n");
267 mutex_unlock(&minor_lock);
268 return retval < 0 ? retval : 0;
271 static void macvtap_free_minor(struct macvlan_dev *vlan)
273 mutex_lock(&minor_lock);
275 idr_remove(&minor_idr, vlan->minor);
278 mutex_unlock(&minor_lock);
281 static struct net_device *dev_get_by_macvtap_minor(int minor)
283 struct net_device *dev = NULL;
284 struct macvlan_dev *vlan;
286 mutex_lock(&minor_lock);
287 vlan = idr_find(&minor_idr, minor);
292 mutex_unlock(&minor_lock);
296 static int macvtap_newlink(struct net *src_net,
297 struct net_device *dev,
299 struct nlattr *data[])
301 /* Don't put anything that may fail after macvlan_common_newlink
302 * because we can't undo what it does.
304 return macvlan_common_newlink(src_net, dev, tb, data,
305 macvtap_receive, macvtap_forward);
308 static void macvtap_dellink(struct net_device *dev,
309 struct list_head *head)
311 macvtap_del_queues(dev);
312 macvlan_dellink(dev, head);
315 static void macvtap_setup(struct net_device *dev)
317 macvlan_common_setup(dev);
318 dev->tx_queue_len = TUN_READQ_SIZE;
321 static struct rtnl_link_ops macvtap_link_ops __read_mostly = {
323 .setup = macvtap_setup,
324 .newlink = macvtap_newlink,
325 .dellink = macvtap_dellink,
329 static void macvtap_sock_write_space(struct sock *sk)
331 wait_queue_head_t *wqueue;
333 if (!sock_writeable(sk) ||
334 !test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags))
337 wqueue = sk_sleep(sk);
338 if (wqueue && waitqueue_active(wqueue))
339 wake_up_interruptible_poll(wqueue, POLLOUT | POLLWRNORM | POLLWRBAND);
342 static void macvtap_sock_destruct(struct sock *sk)
344 skb_queue_purge(&sk->sk_receive_queue);
347 static int macvtap_open(struct inode *inode, struct file *file)
349 struct net *net = current->nsproxy->net_ns;
350 struct net_device *dev = dev_get_by_macvtap_minor(iminor(inode));
351 struct macvtap_queue *q;
359 q = (struct macvtap_queue *)sk_alloc(net, AF_UNSPEC, GFP_KERNEL,
365 init_waitqueue_head(&q->wq.wait);
366 q->sock.type = SOCK_RAW;
367 q->sock.state = SS_CONNECTED;
369 q->sock.ops = &macvtap_socket_ops;
370 sock_init_data(&q->sock, &q->sk);
371 q->sk.sk_write_space = macvtap_sock_write_space;
372 q->sk.sk_destruct = macvtap_sock_destruct;
373 q->flags = IFF_VNET_HDR | IFF_NO_PI | IFF_TAP;
374 q->vnet_hdr_sz = sizeof(struct virtio_net_hdr);
377 * so far only KVM virtio_net uses macvtap, enable zero copy between
378 * guest kernel and host kernel when lower device supports zerocopy
380 * The macvlan supports zerocopy iff the lower device supports zero
381 * copy so we don't have to look at the lower device directly.
383 if ((dev->features & NETIF_F_HIGHDMA) && (dev->features & NETIF_F_SG))
384 sock_set_flag(&q->sk, SOCK_ZEROCOPY);
386 err = macvtap_set_queue(dev, file, q);
397 static int macvtap_release(struct inode *inode, struct file *file)
399 struct macvtap_queue *q = file->private_data;
400 macvtap_put_queue(q);
404 static unsigned int macvtap_poll(struct file *file, poll_table * wait)
406 struct macvtap_queue *q = file->private_data;
407 unsigned int mask = POLLERR;
413 poll_wait(file, &q->wq.wait, wait);
415 if (!skb_queue_empty(&q->sk.sk_receive_queue))
416 mask |= POLLIN | POLLRDNORM;
418 if (sock_writeable(&q->sk) ||
419 (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &q->sock.flags) &&
420 sock_writeable(&q->sk)))
421 mask |= POLLOUT | POLLWRNORM;
427 static inline struct sk_buff *macvtap_alloc_skb(struct sock *sk, size_t prepad,
428 size_t len, size_t linear,
429 int noblock, int *err)
433 /* Under a page? Don't bother with paged skb. */
434 if (prepad + len < PAGE_SIZE || !linear)
437 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
442 skb_reserve(skb, prepad);
443 skb_put(skb, linear);
444 skb->data_len = len - linear;
445 skb->len += len - linear;
450 /* set skb frags from iovec, this can move to core network code for reuse */
451 static int zerocopy_sg_from_iovec(struct sk_buff *skb, const struct iovec *from,
452 int offset, size_t count)
454 int len = iov_length(from, count) - offset;
455 int copy = skb_headlen(skb);
456 int size, offset1 = 0;
459 /* Skip over from offset */
460 while (count && (offset >= from->iov_len)) {
461 offset -= from->iov_len;
466 /* copy up to skb headlen */
467 while (count && (copy > 0)) {
468 size = min_t(unsigned int, copy, from->iov_len - offset);
469 if (copy_from_user(skb->data + offset1, from->iov_base + offset,
486 struct page *page[MAX_SKB_FRAGS];
489 unsigned long truesize;
491 len = from->iov_len - offset;
497 base = (unsigned long)from->iov_base + offset;
498 size = ((base & ~PAGE_MASK) + len + ~PAGE_MASK) >> PAGE_SHIFT;
499 if (i + size > MAX_SKB_FRAGS)
501 num_pages = get_user_pages_fast(base, size, 0, &page[i]);
502 if (num_pages != size) {
503 for (i = 0; i < num_pages; i++)
507 truesize = size * PAGE_SIZE;
508 skb->data_len += len;
510 skb->truesize += truesize;
511 atomic_add(truesize, &skb->sk->sk_wmem_alloc);
513 int off = base & ~PAGE_MASK;
514 int size = min_t(int, len, PAGE_SIZE - off);
515 __skb_fill_page_desc(skb, i, page[i], off, size);
516 skb_shinfo(skb)->nr_frags++;
517 /* increase sk_wmem_alloc */
529 * macvtap_skb_from_vnet_hdr and macvtap_skb_to_vnet_hdr should
530 * be shared with the tun/tap driver.
532 static int macvtap_skb_from_vnet_hdr(struct sk_buff *skb,
533 struct virtio_net_hdr *vnet_hdr)
535 unsigned short gso_type = 0;
536 if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
537 switch (vnet_hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
538 case VIRTIO_NET_HDR_GSO_TCPV4:
539 gso_type = SKB_GSO_TCPV4;
541 case VIRTIO_NET_HDR_GSO_TCPV6:
542 gso_type = SKB_GSO_TCPV6;
544 case VIRTIO_NET_HDR_GSO_UDP:
545 gso_type = SKB_GSO_UDP;
551 if (vnet_hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN)
552 gso_type |= SKB_GSO_TCP_ECN;
554 if (vnet_hdr->gso_size == 0)
558 if (vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
559 if (!skb_partial_csum_set(skb, vnet_hdr->csum_start,
560 vnet_hdr->csum_offset))
564 if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
565 skb_shinfo(skb)->gso_size = vnet_hdr->gso_size;
566 skb_shinfo(skb)->gso_type = gso_type;
568 /* Header must be checked, and gso_segs computed. */
569 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
570 skb_shinfo(skb)->gso_segs = 0;
575 static int macvtap_skb_to_vnet_hdr(const struct sk_buff *skb,
576 struct virtio_net_hdr *vnet_hdr)
578 memset(vnet_hdr, 0, sizeof(*vnet_hdr));
580 if (skb_is_gso(skb)) {
581 struct skb_shared_info *sinfo = skb_shinfo(skb);
583 /* This is a hint as to how much should be linear. */
584 vnet_hdr->hdr_len = skb_headlen(skb);
585 vnet_hdr->gso_size = sinfo->gso_size;
586 if (sinfo->gso_type & SKB_GSO_TCPV4)
587 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
588 else if (sinfo->gso_type & SKB_GSO_TCPV6)
589 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
590 else if (sinfo->gso_type & SKB_GSO_UDP)
591 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
594 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
595 vnet_hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
597 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
599 if (skb->ip_summed == CHECKSUM_PARTIAL) {
600 vnet_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
601 vnet_hdr->csum_start = skb_checksum_start_offset(skb);
602 vnet_hdr->csum_offset = skb->csum_offset;
603 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
604 vnet_hdr->flags = VIRTIO_NET_HDR_F_DATA_VALID;
605 } /* else everything is zero */
611 /* Get packet from user space buffer */
612 static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
613 const struct iovec *iv, unsigned long total_len,
614 size_t count, int noblock)
617 struct macvlan_dev *vlan;
618 unsigned long len = total_len;
620 struct virtio_net_hdr vnet_hdr = { 0 };
621 int vnet_hdr_len = 0;
623 bool zerocopy = false;
625 if (q->flags & IFF_VNET_HDR) {
626 vnet_hdr_len = q->vnet_hdr_sz;
629 if (len < vnet_hdr_len)
633 err = memcpy_fromiovecend((void *)&vnet_hdr, iv, 0,
637 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
638 vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
640 vnet_hdr.hdr_len = vnet_hdr.csum_start +
641 vnet_hdr.csum_offset + 2;
643 if (vnet_hdr.hdr_len > len)
648 if (unlikely(len < ETH_HLEN))
652 if (unlikely(count > UIO_MAXIOV))
655 if (m && m->msg_control && sock_flag(&q->sk, SOCK_ZEROCOPY))
659 /* Userspace may produce vectors with count greater than
660 * MAX_SKB_FRAGS, so we need to linearize parts of the skb
661 * to let the rest of data to be fit in the frags.
663 if (count > MAX_SKB_FRAGS) {
664 copylen = iov_length(iv, count - MAX_SKB_FRAGS);
665 if (copylen < vnet_hdr_len)
668 copylen -= vnet_hdr_len;
670 /* There are 256 bytes to be copied in skb, so there is enough
671 * room for skb expand head in case it is used.
672 * The rest buffer is mapped from userspace.
674 if (copylen < vnet_hdr.hdr_len)
675 copylen = vnet_hdr.hdr_len;
677 copylen = GOODCOPY_LEN;
681 skb = macvtap_alloc_skb(&q->sk, NET_IP_ALIGN, copylen,
682 vnet_hdr.hdr_len, noblock, &err);
687 err = zerocopy_sg_from_iovec(skb, iv, vnet_hdr_len, count);
689 err = skb_copy_datagram_from_iovec(skb, 0, iv, vnet_hdr_len,
694 skb_set_network_header(skb, ETH_HLEN);
695 skb_reset_mac_header(skb);
696 skb->protocol = eth_hdr(skb)->h_proto;
699 err = macvtap_skb_from_vnet_hdr(skb, &vnet_hdr);
704 skb_probe_transport_header(skb, ETH_HLEN);
707 vlan = rcu_dereference_bh(q->vlan);
708 /* copy skb_ubuf_info for callback when skb has no error */
710 skb_shinfo(skb)->destructor_arg = m->msg_control;
711 skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY;
712 skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG;
715 macvlan_start_xmit(skb, vlan->dev);
718 rcu_read_unlock_bh();
727 vlan = rcu_dereference_bh(q->vlan);
729 vlan->dev->stats.tx_dropped++;
730 rcu_read_unlock_bh();
735 static ssize_t macvtap_aio_write(struct kiocb *iocb, const struct iovec *iv,
736 unsigned long count, loff_t pos)
738 struct file *file = iocb->ki_filp;
739 ssize_t result = -ENOLINK;
740 struct macvtap_queue *q = file->private_data;
742 result = macvtap_get_user(q, NULL, iv, iov_length(iv, count), count,
743 file->f_flags & O_NONBLOCK);
747 /* Put packet to the user space buffer */
748 static ssize_t macvtap_put_user(struct macvtap_queue *q,
749 const struct sk_buff *skb,
750 const struct iovec *iv, int len)
752 struct macvlan_dev *vlan;
754 int vnet_hdr_len = 0;
758 if (q->flags & IFF_VNET_HDR) {
759 struct virtio_net_hdr vnet_hdr;
760 vnet_hdr_len = q->vnet_hdr_sz;
761 if ((len -= vnet_hdr_len) < 0)
764 ret = macvtap_skb_to_vnet_hdr(skb, &vnet_hdr);
768 if (memcpy_toiovecend(iv, (void *)&vnet_hdr, 0, sizeof(vnet_hdr)))
771 copied = vnet_hdr_len;
773 if (!vlan_tx_tag_present(skb))
774 len = min_t(int, skb->len, len);
781 veth.h_vlan_proto = htons(ETH_P_8021Q);
782 veth.h_vlan_TCI = htons(vlan_tx_tag_get(skb));
784 vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto);
785 len = min_t(int, skb->len + VLAN_HLEN, len);
787 copy = min_t(int, vlan_offset, len);
788 ret = skb_copy_datagram_const_iovec(skb, 0, iv, copied, copy);
794 copy = min_t(int, sizeof(veth), len);
795 ret = memcpy_toiovecend(iv, (void *)&veth, copied, copy);
802 ret = skb_copy_datagram_const_iovec(skb, vlan_offset, iv, copied, len);
807 vlan = rcu_dereference_bh(q->vlan);
809 macvlan_count_rx(vlan, copied - vnet_hdr_len, ret == 0, 0);
810 rcu_read_unlock_bh();
812 return ret ? ret : copied;
815 static ssize_t macvtap_do_read(struct macvtap_queue *q, struct kiocb *iocb,
816 const struct iovec *iv, unsigned long len,
825 prepare_to_wait(sk_sleep(&q->sk), &wait,
828 /* Read frames from the queue */
829 skb = skb_dequeue(&q->sk.sk_receive_queue);
835 if (signal_pending(current)) {
839 /* Nothing to read, let's sleep */
843 ret = macvtap_put_user(q, skb, iv, len);
849 finish_wait(sk_sleep(&q->sk), &wait);
853 static ssize_t macvtap_aio_read(struct kiocb *iocb, const struct iovec *iv,
854 unsigned long count, loff_t pos)
856 struct file *file = iocb->ki_filp;
857 struct macvtap_queue *q = file->private_data;
858 ssize_t len, ret = 0;
860 len = iov_length(iv, count);
866 ret = macvtap_do_read(q, iocb, iv, len, file->f_flags & O_NONBLOCK);
867 ret = min_t(ssize_t, ret, len); /* XXX copied from tun.c. Why? */
872 static struct macvlan_dev *macvtap_get_vlan(struct macvtap_queue *q)
874 struct macvlan_dev *vlan;
877 vlan = rcu_dereference_bh(q->vlan);
880 rcu_read_unlock_bh();
885 static void macvtap_put_vlan(struct macvlan_dev *vlan)
891 * provide compatibility with generic tun/tap interface
893 static long macvtap_ioctl(struct file *file, unsigned int cmd,
896 struct macvtap_queue *q = file->private_data;
897 struct macvlan_dev *vlan;
898 void __user *argp = (void __user *)arg;
899 struct ifreq __user *ifr = argp;
900 unsigned int __user *up = argp;
902 int __user *sp = argp;
908 /* ignore the name, just look at flags */
909 if (get_user(u, &ifr->ifr_flags))
913 if ((u & ~IFF_VNET_HDR) != (IFF_NO_PI | IFF_TAP))
921 vlan = macvtap_get_vlan(q);
926 if (copy_to_user(&ifr->ifr_name, vlan->dev->name, IFNAMSIZ) ||
927 put_user(q->flags, &ifr->ifr_flags))
929 macvtap_put_vlan(vlan);
933 if (put_user(IFF_TAP | IFF_NO_PI | IFF_VNET_HDR, up))
944 case TUNGETVNETHDRSZ:
950 case TUNSETVNETHDRSZ:
953 if (s < (int)sizeof(struct virtio_net_hdr))
960 /* let the user check for future flags */
961 if (arg & ~(TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6 |
962 TUN_F_TSO_ECN | TUN_F_UFO))
965 /* TODO: only accept frames with the features that
966 got enabled for forwarded frames */
967 if (!(q->flags & IFF_VNET_HDR))
977 static long macvtap_compat_ioctl(struct file *file, unsigned int cmd,
980 return macvtap_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
984 static const struct file_operations macvtap_fops = {
985 .owner = THIS_MODULE,
986 .open = macvtap_open,
987 .release = macvtap_release,
988 .aio_read = macvtap_aio_read,
989 .aio_write = macvtap_aio_write,
990 .poll = macvtap_poll,
992 .unlocked_ioctl = macvtap_ioctl,
994 .compat_ioctl = macvtap_compat_ioctl,
998 static int macvtap_sendmsg(struct kiocb *iocb, struct socket *sock,
999 struct msghdr *m, size_t total_len)
1001 struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock);
1002 return macvtap_get_user(q, m, m->msg_iov, total_len, m->msg_iovlen,
1003 m->msg_flags & MSG_DONTWAIT);
1006 static int macvtap_recvmsg(struct kiocb *iocb, struct socket *sock,
1007 struct msghdr *m, size_t total_len,
1010 struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock);
1012 if (flags & ~(MSG_DONTWAIT|MSG_TRUNC))
1014 ret = macvtap_do_read(q, iocb, m->msg_iov, total_len,
1015 flags & MSG_DONTWAIT);
1016 if (ret > total_len) {
1017 m->msg_flags |= MSG_TRUNC;
1018 ret = flags & MSG_TRUNC ? ret : total_len;
1023 /* Ops structure to mimic raw sockets with tun */
1024 static const struct proto_ops macvtap_socket_ops = {
1025 .sendmsg = macvtap_sendmsg,
1026 .recvmsg = macvtap_recvmsg,
1029 /* Get an underlying socket object from tun file. Returns error unless file is
1030 * attached to a device. The returned object works like a packet socket, it
1031 * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for
1032 * holding a reference to the file for as long as the socket is in use. */
1033 struct socket *macvtap_get_socket(struct file *file)
1035 struct macvtap_queue *q;
1036 if (file->f_op != &macvtap_fops)
1037 return ERR_PTR(-EINVAL);
1038 q = file->private_data;
1040 return ERR_PTR(-EBADFD);
1043 EXPORT_SYMBOL_GPL(macvtap_get_socket);
1045 static int macvtap_device_event(struct notifier_block *unused,
1046 unsigned long event, void *ptr)
1048 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1049 struct macvlan_dev *vlan;
1050 struct device *classdev;
1054 if (dev->rtnl_link_ops != &macvtap_link_ops)
1057 vlan = netdev_priv(dev);
1060 case NETDEV_REGISTER:
1061 /* Create the device node here after the network device has
1062 * been registered but before register_netdevice has
1065 err = macvtap_get_minor(vlan);
1067 return notifier_from_errno(err);
1069 devt = MKDEV(MAJOR(macvtap_major), vlan->minor);
1070 classdev = device_create(macvtap_class, &dev->dev, devt,
1071 dev, "tap%d", dev->ifindex);
1072 if (IS_ERR(classdev)) {
1073 macvtap_free_minor(vlan);
1074 return notifier_from_errno(PTR_ERR(classdev));
1077 case NETDEV_UNREGISTER:
1078 devt = MKDEV(MAJOR(macvtap_major), vlan->minor);
1079 device_destroy(macvtap_class, devt);
1080 macvtap_free_minor(vlan);
1087 static struct notifier_block macvtap_notifier_block __read_mostly = {
1088 .notifier_call = macvtap_device_event,
1091 static int macvtap_init(void)
1095 err = alloc_chrdev_region(&macvtap_major, 0,
1096 MACVTAP_NUM_DEVS, "macvtap");
1100 cdev_init(&macvtap_cdev, &macvtap_fops);
1101 err = cdev_add(&macvtap_cdev, macvtap_major, MACVTAP_NUM_DEVS);
1105 macvtap_class = class_create(THIS_MODULE, "macvtap");
1106 if (IS_ERR(macvtap_class)) {
1107 err = PTR_ERR(macvtap_class);
1111 err = register_netdevice_notifier(&macvtap_notifier_block);
1115 err = macvlan_link_register(&macvtap_link_ops);
1122 unregister_netdevice_notifier(&macvtap_notifier_block);
1124 class_unregister(macvtap_class);
1126 cdev_del(&macvtap_cdev);
1128 unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
1132 module_init(macvtap_init);
1134 static void macvtap_exit(void)
1136 rtnl_link_unregister(&macvtap_link_ops);
1137 unregister_netdevice_notifier(&macvtap_notifier_block);
1138 class_unregister(macvtap_class);
1139 cdev_del(&macvtap_cdev);
1140 unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
1142 module_exit(macvtap_exit);
1144 MODULE_ALIAS_RTNL_LINK("macvtap");
1145 MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
1146 MODULE_LICENSE("GPL");