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
35 struct macvtap_queue
{
40 struct macvlan_dev __rcu
*vlan
;
45 struct list_head next
;
48 static struct proto macvtap_proto
= {
51 .obj_size
= sizeof (struct macvtap_queue
),
55 * Variables for dealing with macvtaps device numbers.
57 static dev_t macvtap_major
;
58 #define MACVTAP_NUM_DEVS (1U << MINORBITS)
59 static DEFINE_MUTEX(minor_lock
);
60 static DEFINE_IDR(minor_idr
);
62 #define GOODCOPY_LEN 128
63 static struct class *macvtap_class
;
64 static struct cdev macvtap_cdev
;
66 static const struct proto_ops macvtap_socket_ops
;
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)
75 * The macvtap_queue and the macvlan_dev are loosely coupled, the
76 * pointers from one to the other can only be read while rcu_read_lock
79 * Both the file and the macvlan_dev hold a reference on the macvtap_queue
80 * through sock_hold(&q->sk). When the macvlan_dev goes away first,
81 * q->vlan becomes inaccessible. When the files gets closed,
82 * macvtap_get_queue() fails.
84 * There may still be references to the struct sock inside of the
85 * queue from outbound SKBs, but these never reference back to the
86 * file or the dev. The data structure is freed through __sk_free
87 * when both our references and any pending SKBs are gone.
90 static int macvtap_enable_queue(struct net_device
*dev
, struct file
*file
,
91 struct macvtap_queue
*q
)
93 struct macvlan_dev
*vlan
= netdev_priv(dev
);
102 rcu_assign_pointer(vlan
->taps
[vlan
->numvtaps
], q
);
103 q
->queue_index
= vlan
->numvtaps
;
111 static int macvtap_set_queue(struct net_device
*dev
, struct file
*file
,
112 struct macvtap_queue
*q
)
114 struct macvlan_dev
*vlan
= netdev_priv(dev
);
118 if (vlan
->numqueues
== MAX_MACVTAP_QUEUES
)
122 rcu_assign_pointer(q
->vlan
, vlan
);
123 rcu_assign_pointer(vlan
->taps
[vlan
->numvtaps
], q
);
127 q
->queue_index
= vlan
->numvtaps
;
129 file
->private_data
= q
;
130 list_add_tail(&q
->next
, &vlan
->queue_list
);
140 static int macvtap_disable_queue(struct macvtap_queue
*q
)
142 struct macvlan_dev
*vlan
;
143 struct macvtap_queue
*nq
;
149 vlan
= rtnl_dereference(q
->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
;
157 rcu_assign_pointer(vlan
->taps
[index
], nq
);
158 RCU_INIT_POINTER(vlan
->taps
[vlan
->numvtaps
- 1], NULL
);
168 * The file owning the queue got closed, give up both
169 * the reference that the files holds as well as the
170 * one from the macvlan_dev if that still exists.
172 * Using the spinlock makes sure that we don't get
173 * to the queue again after destroying it.
175 static void macvtap_put_queue(struct macvtap_queue
*q
)
177 struct macvlan_dev
*vlan
;
180 vlan
= rtnl_dereference(q
->vlan
);
184 BUG_ON(macvtap_disable_queue(q
));
187 RCU_INIT_POINTER(q
->vlan
, NULL
);
189 list_del_init(&q
->next
);
199 * Select a queue based on the rxq of the device on which this packet
200 * arrived. If the incoming device is not mq, calculate a flow hash
201 * to select a queue. If all fails, find the first available queue.
202 * Cache vlan->numvtaps since it can become zero during the execution
205 static struct macvtap_queue
*macvtap_get_queue(struct net_device
*dev
,
208 struct macvlan_dev
*vlan
= netdev_priv(dev
);
209 struct macvtap_queue
*tap
= NULL
;
210 /* Access to taps array is protected by rcu, but access to numvtaps
211 * isn't. Below we use it to lookup a queue, but treat it as a hint
212 * and validate that the result isn't NULL - in case we are
213 * racing against queue removal.
215 int numvtaps
= ACCESS_ONCE(vlan
->numvtaps
);
221 /* Check if we can use flow to select a queue */
222 rxq
= skb_get_rxhash(skb
);
224 tap
= rcu_dereference(vlan
->taps
[rxq
% numvtaps
]);
228 if (likely(skb_rx_queue_recorded(skb
))) {
229 rxq
= skb_get_rx_queue(skb
);
231 while (unlikely(rxq
>= numvtaps
))
234 tap
= rcu_dereference(vlan
->taps
[rxq
]);
238 tap
= rcu_dereference(vlan
->taps
[0]);
244 * The net_device is going away, give up the reference
245 * that it holds on all queues and safely set the pointer
246 * from the queues to NULL.
248 static void macvtap_del_queues(struct net_device
*dev
)
250 struct macvlan_dev
*vlan
= netdev_priv(dev
);
251 struct macvtap_queue
*q
, *tmp
, *qlist
[MAX_MACVTAP_QUEUES
];
255 list_for_each_entry_safe(q
, tmp
, &vlan
->queue_list
, next
) {
256 list_del_init(&q
->next
);
258 RCU_INIT_POINTER(q
->vlan
, NULL
);
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 /* guarantee that any future macvtap_set_queue will fail */
268 vlan
->numvtaps
= MAX_MACVTAP_QUEUES
;
270 for (--j
; j
>= 0; j
--)
271 sock_put(&qlist
[j
]->sk
);
275 * Forward happens for data that gets sent from one macvlan
276 * endpoint to another one in bridge mode. We just take
277 * the skb and put it into the receive queue.
279 static int macvtap_forward(struct net_device
*dev
, struct sk_buff
*skb
)
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
;
288 if (skb_queue_len(&q
->sk
.sk_receive_queue
) >= dev
->tx_queue_len
)
292 /* Apply the forward feature mask so that we perform segmentation
293 * according to users wishes. This only works if VNET_HDR is
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);
305 skb_queue_tail(&q
->sk
.sk_receive_queue
, skb
);
311 struct sk_buff
*nskb
= segs
->next
;
314 skb_queue_tail(&q
->sk
.sk_receive_queue
, segs
);
318 skb_queue_tail(&q
->sk
.sk_receive_queue
, skb
);
322 wake_up_interruptible_poll(sk_sleep(&q
->sk
), POLLIN
| POLLRDNORM
| POLLRDBAND
);
323 return NET_RX_SUCCESS
;
331 * Receive is for data from the external interface (lowerdev),
332 * in case of macvtap, we can treat that the same way as
333 * forward, which macvlan cannot.
335 static int macvtap_receive(struct sk_buff
*skb
)
337 skb_push(skb
, ETH_HLEN
);
338 return macvtap_forward(skb
->dev
, skb
);
341 static int macvtap_get_minor(struct macvlan_dev
*vlan
)
343 int retval
= -ENOMEM
;
345 mutex_lock(&minor_lock
);
346 retval
= idr_alloc(&minor_idr
, vlan
, 1, MACVTAP_NUM_DEVS
, GFP_KERNEL
);
348 vlan
->minor
= retval
;
349 } else if (retval
== -ENOSPC
) {
350 printk(KERN_ERR
"too many macvtap devices\n");
353 mutex_unlock(&minor_lock
);
354 return retval
< 0 ? retval
: 0;
357 static void macvtap_free_minor(struct macvlan_dev
*vlan
)
359 mutex_lock(&minor_lock
);
361 idr_remove(&minor_idr
, vlan
->minor
);
364 mutex_unlock(&minor_lock
);
367 static struct net_device
*dev_get_by_macvtap_minor(int minor
)
369 struct net_device
*dev
= NULL
;
370 struct macvlan_dev
*vlan
;
372 mutex_lock(&minor_lock
);
373 vlan
= idr_find(&minor_idr
, minor
);
378 mutex_unlock(&minor_lock
);
382 static int macvtap_newlink(struct net
*src_net
,
383 struct net_device
*dev
,
385 struct nlattr
*data
[])
387 struct macvlan_dev
*vlan
= netdev_priv(dev
);
388 INIT_LIST_HEAD(&vlan
->queue_list
);
390 /* Since macvlan supports all offloads by default, make
391 * tap support all offloads also.
393 vlan
->tap_features
= TUN_OFFLOADS
;
395 /* Don't put anything that may fail after macvlan_common_newlink
396 * because we can't undo what it does.
398 return macvlan_common_newlink(src_net
, dev
, tb
, data
,
399 macvtap_receive
, macvtap_forward
);
402 static void macvtap_dellink(struct net_device
*dev
,
403 struct list_head
*head
)
405 macvtap_del_queues(dev
);
406 macvlan_dellink(dev
, head
);
409 static void macvtap_setup(struct net_device
*dev
)
411 macvlan_common_setup(dev
);
412 dev
->tx_queue_len
= TUN_READQ_SIZE
;
415 static struct rtnl_link_ops macvtap_link_ops __read_mostly
= {
417 .setup
= macvtap_setup
,
418 .newlink
= macvtap_newlink
,
419 .dellink
= macvtap_dellink
,
423 static void macvtap_sock_write_space(struct sock
*sk
)
425 wait_queue_head_t
*wqueue
;
427 if (!sock_writeable(sk
) ||
428 !test_and_clear_bit(SOCK_ASYNC_NOSPACE
, &sk
->sk_socket
->flags
))
431 wqueue
= sk_sleep(sk
);
432 if (wqueue
&& waitqueue_active(wqueue
))
433 wake_up_interruptible_poll(wqueue
, POLLOUT
| POLLWRNORM
| POLLWRBAND
);
436 static void macvtap_sock_destruct(struct sock
*sk
)
438 skb_queue_purge(&sk
->sk_receive_queue
);
441 static int macvtap_open(struct inode
*inode
, struct file
*file
)
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
;
453 q
= (struct macvtap_queue
*)sk_alloc(net
, AF_UNSPEC
, GFP_KERNEL
,
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
;
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
);
471 * so far only KVM virtio_net uses macvtap, enable zero copy between
472 * guest kernel and host kernel when lower device supports zerocopy
474 * The macvlan supports zerocopy iff the lower device supports zero
475 * copy so we don't have to look at the lower device directly.
477 if ((dev
->features
& NETIF_F_HIGHDMA
) && (dev
->features
& NETIF_F_SG
))
478 sock_set_flag(&q
->sk
, SOCK_ZEROCOPY
);
480 err
= macvtap_set_queue(dev
, file
, q
);
491 static int macvtap_release(struct inode
*inode
, struct file
*file
)
493 struct macvtap_queue
*q
= file
->private_data
;
494 macvtap_put_queue(q
);
498 static unsigned int macvtap_poll(struct file
*file
, poll_table
* wait
)
500 struct macvtap_queue
*q
= file
->private_data
;
501 unsigned int mask
= POLLERR
;
507 poll_wait(file
, &q
->wq
.wait
, wait
);
509 if (!skb_queue_empty(&q
->sk
.sk_receive_queue
))
510 mask
|= POLLIN
| POLLRDNORM
;
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
;
521 static 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
)
527 /* Under a page? Don't bother with paged skb. */
528 if (prepad
+ len
< PAGE_SIZE
|| !linear
)
531 skb
= sock_alloc_send_pskb(sk
, prepad
+ linear
, len
- linear
, noblock
,
536 skb_reserve(skb
, prepad
);
537 skb_put(skb
, linear
);
538 skb
->data_len
= len
- linear
;
539 skb
->len
+= len
- linear
;
545 * macvtap_skb_from_vnet_hdr and macvtap_skb_to_vnet_hdr should
546 * be shared with the tun/tap driver.
548 static int macvtap_skb_from_vnet_hdr(struct sk_buff
*skb
,
549 struct virtio_net_hdr
*vnet_hdr
)
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
;
557 case VIRTIO_NET_HDR_GSO_TCPV6
:
558 gso_type
= SKB_GSO_TCPV6
;
560 case VIRTIO_NET_HDR_GSO_UDP
:
561 gso_type
= SKB_GSO_UDP
;
567 if (vnet_hdr
->gso_type
& VIRTIO_NET_HDR_GSO_ECN
)
568 gso_type
|= SKB_GSO_TCP_ECN
;
570 if (vnet_hdr
->gso_size
== 0)
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
))
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
;
584 /* Header must be checked, and gso_segs computed. */
585 skb_shinfo(skb
)->gso_type
|= SKB_GSO_DODGY
;
586 skb_shinfo(skb
)->gso_segs
= 0;
591 static void macvtap_skb_to_vnet_hdr(const struct sk_buff
*skb
,
592 struct virtio_net_hdr
*vnet_hdr
)
594 memset(vnet_hdr
, 0, sizeof(*vnet_hdr
));
596 if (skb_is_gso(skb
)) {
597 struct skb_shared_info
*sinfo
= skb_shinfo(skb
);
599 /* This is a hint as to how much should be linear. */
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
;
610 if (sinfo
->gso_type
& SKB_GSO_TCP_ECN
)
611 vnet_hdr
->gso_type
|= VIRTIO_NET_HDR_GSO_ECN
;
613 vnet_hdr
->gso_type
= VIRTIO_NET_HDR_GSO_NONE
;
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 } /* else everything is zero */
624 /* Get packet from user space buffer */
625 static ssize_t
macvtap_get_user(struct macvtap_queue
*q
, struct msghdr
*m
,
626 const struct iovec
*iv
, unsigned long total_len
,
627 size_t count
, int noblock
)
629 int good_linear
= SKB_MAX_HEAD(NET_IP_ALIGN
);
631 struct macvlan_dev
*vlan
;
632 unsigned long len
= total_len
;
634 struct virtio_net_hdr vnet_hdr
= { 0 };
635 int vnet_hdr_len
= 0;
637 bool zerocopy
= false;
640 if (q
->flags
& IFF_VNET_HDR
) {
641 vnet_hdr_len
= q
->vnet_hdr_sz
;
644 if (len
< vnet_hdr_len
)
648 err
= memcpy_fromiovecend((void *)&vnet_hdr
, iv
, 0,
652 if ((vnet_hdr
.flags
& VIRTIO_NET_HDR_F_NEEDS_CSUM
) &&
653 vnet_hdr
.csum_start
+ vnet_hdr
.csum_offset
+ 2 >
655 vnet_hdr
.hdr_len
= vnet_hdr
.csum_start
+
656 vnet_hdr
.csum_offset
+ 2;
658 if (vnet_hdr
.hdr_len
> len
)
663 if (unlikely(len
< ETH_HLEN
))
667 if (unlikely(count
> UIO_MAXIOV
))
670 if (m
&& m
->msg_control
&& sock_flag(&q
->sk
, SOCK_ZEROCOPY
)) {
671 copylen
= vnet_hdr
.hdr_len
? vnet_hdr
.hdr_len
: GOODCOPY_LEN
;
672 if (copylen
> good_linear
)
673 copylen
= good_linear
;
675 if (iov_pages(iv
, vnet_hdr_len
+ copylen
, count
)
682 if (vnet_hdr
.hdr_len
> good_linear
)
683 linear
= good_linear
;
685 linear
= vnet_hdr
.hdr_len
;
688 skb
= macvtap_alloc_skb(&q
->sk
, NET_IP_ALIGN
, copylen
,
689 linear
, noblock
, &err
);
694 err
= zerocopy_sg_from_iovec(skb
, iv
, vnet_hdr_len
, count
);
696 err
= skb_copy_datagram_from_iovec(skb
, 0, iv
, vnet_hdr_len
,
698 if (!err
&& m
&& m
->msg_control
) {
699 struct ubuf_info
*uarg
= m
->msg_control
;
700 uarg
->callback(uarg
, false);
707 skb_set_network_header(skb
, ETH_HLEN
);
708 skb_reset_mac_header(skb
);
709 skb
->protocol
= eth_hdr(skb
)->h_proto
;
712 err
= macvtap_skb_from_vnet_hdr(skb
, &vnet_hdr
);
717 skb_probe_transport_header(skb
, ETH_HLEN
);
720 vlan
= rcu_dereference(q
->vlan
);
721 /* copy skb_ubuf_info for callback when skb has no error */
723 skb_shinfo(skb
)->destructor_arg
= m
->msg_control
;
724 skb_shinfo(skb
)->tx_flags
|= SKBTX_DEV_ZEROCOPY
;
725 skb_shinfo(skb
)->tx_flags
|= SKBTX_SHARED_FRAG
;
729 macvlan_start_xmit(skb
, vlan
->dev
);
743 vlan
= rcu_dereference(q
->vlan
);
745 this_cpu_inc(vlan
->pcpu_stats
->tx_dropped
);
751 static ssize_t
macvtap_aio_write(struct kiocb
*iocb
, const struct iovec
*iv
,
752 unsigned long count
, loff_t pos
)
754 struct file
*file
= iocb
->ki_filp
;
755 ssize_t result
= -ENOLINK
;
756 struct macvtap_queue
*q
= file
->private_data
;
758 result
= macvtap_get_user(q
, NULL
, iv
, iov_length(iv
, count
), count
,
759 file
->f_flags
& O_NONBLOCK
);
763 /* Put packet to the user space buffer */
764 static ssize_t
macvtap_put_user(struct macvtap_queue
*q
,
765 const struct sk_buff
*skb
,
766 const struct iovec
*iv
, int len
)
769 int vnet_hdr_len
= 0;
773 if (q
->flags
& IFF_VNET_HDR
) {
774 struct virtio_net_hdr vnet_hdr
;
775 vnet_hdr_len
= q
->vnet_hdr_sz
;
776 if ((len
-= vnet_hdr_len
) < 0)
779 macvtap_skb_to_vnet_hdr(skb
, &vnet_hdr
);
781 if (memcpy_toiovecend(iv
, (void *)&vnet_hdr
, 0, sizeof(vnet_hdr
)))
784 copied
= vnet_hdr_len
;
786 if (!vlan_tx_tag_present(skb
))
787 len
= min_t(int, skb
->len
, len
);
794 veth
.h_vlan_proto
= skb
->vlan_proto
;
795 veth
.h_vlan_TCI
= htons(vlan_tx_tag_get(skb
));
797 vlan_offset
= offsetof(struct vlan_ethhdr
, h_vlan_proto
);
798 len
= min_t(int, skb
->len
+ VLAN_HLEN
, len
);
800 copy
= min_t(int, vlan_offset
, len
);
801 ret
= skb_copy_datagram_const_iovec(skb
, 0, iv
, copied
, copy
);
807 copy
= min_t(int, sizeof(veth
), len
);
808 ret
= memcpy_toiovecend(iv
, (void *)&veth
, copied
, copy
);
815 ret
= skb_copy_datagram_const_iovec(skb
, vlan_offset
, iv
, copied
, len
);
819 return ret
? ret
: copied
;
822 static ssize_t
macvtap_do_read(struct macvtap_queue
*q
,
823 const struct iovec
*iv
, unsigned long len
,
832 prepare_to_wait(sk_sleep(&q
->sk
), &wait
,
835 /* Read frames from the queue */
836 skb
= skb_dequeue(&q
->sk
.sk_receive_queue
);
842 if (signal_pending(current
)) {
846 /* Nothing to read, let's sleep */
850 ret
= macvtap_put_user(q
, skb
, iv
, len
);
856 finish_wait(sk_sleep(&q
->sk
), &wait
);
860 static ssize_t
macvtap_aio_read(struct kiocb
*iocb
, const struct iovec
*iv
,
861 unsigned long count
, loff_t pos
)
863 struct file
*file
= iocb
->ki_filp
;
864 struct macvtap_queue
*q
= file
->private_data
;
865 ssize_t len
, ret
= 0;
867 len
= iov_length(iv
, count
);
873 ret
= macvtap_do_read(q
, iv
, len
, file
->f_flags
& O_NONBLOCK
);
880 static struct macvlan_dev
*macvtap_get_vlan(struct macvtap_queue
*q
)
882 struct macvlan_dev
*vlan
;
885 vlan
= rtnl_dereference(q
->vlan
);
892 static void macvtap_put_vlan(struct macvlan_dev
*vlan
)
897 static int macvtap_ioctl_set_queue(struct file
*file
, unsigned int flags
)
899 struct macvtap_queue
*q
= file
->private_data
;
900 struct macvlan_dev
*vlan
;
903 vlan
= macvtap_get_vlan(q
);
907 if (flags
& IFF_ATTACH_QUEUE
)
908 ret
= macvtap_enable_queue(vlan
->dev
, file
, q
);
909 else if (flags
& IFF_DETACH_QUEUE
)
910 ret
= macvtap_disable_queue(q
);
914 macvtap_put_vlan(vlan
);
918 static int set_offload(struct macvtap_queue
*q
, unsigned long arg
)
920 struct macvlan_dev
*vlan
;
921 netdev_features_t features
;
922 netdev_features_t feature_mask
= 0;
924 vlan
= rtnl_dereference(q
->vlan
);
928 features
= vlan
->dev
->features
;
930 if (arg
& TUN_F_CSUM
) {
931 feature_mask
= NETIF_F_HW_CSUM
;
933 if (arg
& (TUN_F_TSO4
| TUN_F_TSO6
)) {
934 if (arg
& TUN_F_TSO_ECN
)
935 feature_mask
|= NETIF_F_TSO_ECN
;
936 if (arg
& TUN_F_TSO4
)
937 feature_mask
|= NETIF_F_TSO
;
938 if (arg
& TUN_F_TSO6
)
939 feature_mask
|= NETIF_F_TSO6
;
943 feature_mask
|= NETIF_F_UFO
;
946 /* tun/tap driver inverts the usage for TSO offloads, where
947 * setting the TSO bit means that the userspace wants to
948 * accept TSO frames and turning it off means that user space
949 * does not support TSO.
950 * For macvtap, we have to invert it to mean the same thing.
951 * When user space turns off TSO, we turn off GSO/LRO so that
952 * user-space will not receive TSO frames.
954 if (feature_mask
& (NETIF_F_TSO
| NETIF_F_TSO6
| NETIF_F_UFO
))
955 features
|= RX_OFFLOADS
;
957 features
&= ~RX_OFFLOADS
;
959 /* tap_features are the same as features on tun/tap and
960 * reflect user expectations.
962 vlan
->tap_features
= feature_mask
;
963 vlan
->set_features
= features
;
964 netdev_update_features(vlan
->dev
);
970 * provide compatibility with generic tun/tap interface
972 static long macvtap_ioctl(struct file
*file
, unsigned int cmd
,
975 struct macvtap_queue
*q
= file
->private_data
;
976 struct macvlan_dev
*vlan
;
977 void __user
*argp
= (void __user
*)arg
;
978 struct ifreq __user
*ifr
= argp
;
979 unsigned int __user
*up
= argp
;
981 int __user
*sp
= argp
;
987 /* ignore the name, just look at flags */
988 if (get_user(u
, &ifr
->ifr_flags
))
992 if ((u
& ~(IFF_VNET_HDR
| IFF_MULTI_QUEUE
)) !=
993 (IFF_NO_PI
| IFF_TAP
))
1002 vlan
= macvtap_get_vlan(q
);
1009 if (copy_to_user(&ifr
->ifr_name
, vlan
->dev
->name
, IFNAMSIZ
) ||
1010 put_user(q
->flags
, &ifr
->ifr_flags
))
1012 macvtap_put_vlan(vlan
);
1017 if (get_user(u
, &ifr
->ifr_flags
))
1020 ret
= macvtap_ioctl_set_queue(file
, u
);
1024 case TUNGETFEATURES
:
1025 if (put_user(IFF_TAP
| IFF_NO_PI
| IFF_VNET_HDR
|
1026 IFF_MULTI_QUEUE
, up
))
1031 if (get_user(u
, up
))
1034 q
->sk
.sk_sndbuf
= u
;
1037 case TUNGETVNETHDRSZ
:
1039 if (put_user(s
, sp
))
1043 case TUNSETVNETHDRSZ
:
1044 if (get_user(s
, sp
))
1046 if (s
< (int)sizeof(struct virtio_net_hdr
))
1053 /* let the user check for future flags */
1054 if (arg
& ~(TUN_F_CSUM
| TUN_F_TSO4
| TUN_F_TSO6
|
1055 TUN_F_TSO_ECN
| TUN_F_UFO
))
1059 ret
= set_offload(q
, arg
);
1068 #ifdef CONFIG_COMPAT
1069 static long macvtap_compat_ioctl(struct file
*file
, unsigned int cmd
,
1072 return macvtap_ioctl(file
, cmd
, (unsigned long)compat_ptr(arg
));
1076 static const struct file_operations macvtap_fops
= {
1077 .owner
= THIS_MODULE
,
1078 .open
= macvtap_open
,
1079 .release
= macvtap_release
,
1080 .aio_read
= macvtap_aio_read
,
1081 .aio_write
= macvtap_aio_write
,
1082 .poll
= macvtap_poll
,
1083 .llseek
= no_llseek
,
1084 .unlocked_ioctl
= macvtap_ioctl
,
1085 #ifdef CONFIG_COMPAT
1086 .compat_ioctl
= macvtap_compat_ioctl
,
1090 static int macvtap_sendmsg(struct kiocb
*iocb
, struct socket
*sock
,
1091 struct msghdr
*m
, size_t total_len
)
1093 struct macvtap_queue
*q
= container_of(sock
, struct macvtap_queue
, sock
);
1094 return macvtap_get_user(q
, m
, m
->msg_iov
, total_len
, m
->msg_iovlen
,
1095 m
->msg_flags
& MSG_DONTWAIT
);
1098 static int macvtap_recvmsg(struct kiocb
*iocb
, struct socket
*sock
,
1099 struct msghdr
*m
, size_t total_len
,
1102 struct macvtap_queue
*q
= container_of(sock
, struct macvtap_queue
, sock
);
1104 if (flags
& ~(MSG_DONTWAIT
|MSG_TRUNC
))
1106 ret
= macvtap_do_read(q
, m
->msg_iov
, total_len
,
1107 flags
& MSG_DONTWAIT
);
1111 /* Ops structure to mimic raw sockets with tun */
1112 static const struct proto_ops macvtap_socket_ops
= {
1113 .sendmsg
= macvtap_sendmsg
,
1114 .recvmsg
= macvtap_recvmsg
,
1117 /* Get an underlying socket object from tun file. Returns error unless file is
1118 * attached to a device. The returned object works like a packet socket, it
1119 * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for
1120 * holding a reference to the file for as long as the socket is in use. */
1121 struct socket
*macvtap_get_socket(struct file
*file
)
1123 struct macvtap_queue
*q
;
1124 if (file
->f_op
!= &macvtap_fops
)
1125 return ERR_PTR(-EINVAL
);
1126 q
= file
->private_data
;
1128 return ERR_PTR(-EBADFD
);
1131 EXPORT_SYMBOL_GPL(macvtap_get_socket
);
1133 static int macvtap_device_event(struct notifier_block
*unused
,
1134 unsigned long event
, void *ptr
)
1136 struct net_device
*dev
= netdev_notifier_info_to_dev(ptr
);
1137 struct macvlan_dev
*vlan
;
1138 struct device
*classdev
;
1142 if (dev
->rtnl_link_ops
!= &macvtap_link_ops
)
1145 vlan
= netdev_priv(dev
);
1148 case NETDEV_REGISTER
:
1149 /* Create the device node here after the network device has
1150 * been registered but before register_netdevice has
1153 err
= macvtap_get_minor(vlan
);
1155 return notifier_from_errno(err
);
1157 devt
= MKDEV(MAJOR(macvtap_major
), vlan
->minor
);
1158 classdev
= device_create(macvtap_class
, &dev
->dev
, devt
,
1159 dev
, "tap%d", dev
->ifindex
);
1160 if (IS_ERR(classdev
)) {
1161 macvtap_free_minor(vlan
);
1162 return notifier_from_errno(PTR_ERR(classdev
));
1165 case NETDEV_UNREGISTER
:
1166 devt
= MKDEV(MAJOR(macvtap_major
), vlan
->minor
);
1167 device_destroy(macvtap_class
, devt
);
1168 macvtap_free_minor(vlan
);
1175 static struct notifier_block macvtap_notifier_block __read_mostly
= {
1176 .notifier_call
= macvtap_device_event
,
1179 static int macvtap_init(void)
1183 err
= alloc_chrdev_region(&macvtap_major
, 0,
1184 MACVTAP_NUM_DEVS
, "macvtap");
1188 cdev_init(&macvtap_cdev
, &macvtap_fops
);
1189 err
= cdev_add(&macvtap_cdev
, macvtap_major
, MACVTAP_NUM_DEVS
);
1193 macvtap_class
= class_create(THIS_MODULE
, "macvtap");
1194 if (IS_ERR(macvtap_class
)) {
1195 err
= PTR_ERR(macvtap_class
);
1199 err
= register_netdevice_notifier(&macvtap_notifier_block
);
1203 err
= macvlan_link_register(&macvtap_link_ops
);
1210 unregister_netdevice_notifier(&macvtap_notifier_block
);
1212 class_unregister(macvtap_class
);
1214 cdev_del(&macvtap_cdev
);
1216 unregister_chrdev_region(macvtap_major
, MACVTAP_NUM_DEVS
);
1220 module_init(macvtap_init
);
1222 static void macvtap_exit(void)
1224 rtnl_link_unregister(&macvtap_link_ops
);
1225 unregister_netdevice_notifier(&macvtap_notifier_block
);
1226 class_unregister(macvtap_class
);
1227 cdev_del(&macvtap_cdev
);
1228 unregister_chrdev_region(macvtap_major
, MACVTAP_NUM_DEVS
);
1230 module_exit(macvtap_exit
);
1232 MODULE_ALIAS_RTNL_LINK("macvtap");
1233 MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
1234 MODULE_LICENSE("GPL");