blob: 58dc117a8d781b93ba91a258fe87de1e3bf5a7c8 [file] [log] [blame]
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001#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>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090012#include <linux/slab.h>
Arnd Bergmann20d29d72010-01-30 12:24:26 +000013#include <linux/init.h>
14#include <linux/wait.h>
15#include <linux/cdev.h>
16#include <linux/fs.h>
17
18#include <net/net_namespace.h>
19#include <net/rtnetlink.h>
20#include <net/sock.h>
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +000021#include <linux/virtio_net.h>
Arnd Bergmann20d29d72010-01-30 12:24:26 +000022
23/*
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.
28 *
29 * macvtap_proto is used to allocate queues through the sock allocation
30 * mechanism.
31 *
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.
36 */
37struct macvtap_queue {
38 struct sock sk;
39 struct socket sock;
Eric Dumazet43815482010-04-29 11:01:49 +000040 struct socket_wq wq;
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +030041 int vnet_hdr_sz;
Eric Dumazet13707f92011-01-26 19:28:23 +000042 struct macvlan_dev __rcu *vlan;
Arnd Bergmann20d29d72010-01-30 12:24:26 +000043 struct file *file;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +000044 unsigned int flags;
Arnd Bergmann20d29d72010-01-30 12:24:26 +000045};
46
47static struct proto macvtap_proto = {
48 .name = "macvtap",
49 .owner = THIS_MODULE,
50 .obj_size = sizeof (struct macvtap_queue),
51};
52
53/*
Eric W. Biedermane09eff72011-10-20 04:29:24 +000054 * Variables for dealing with macvtaps device numbers.
Arnd Bergmann20d29d72010-01-30 12:24:26 +000055 */
David S. Miller1ebed712010-07-10 19:25:50 -070056static dev_t macvtap_major;
Eric W. Biedermane09eff72011-10-20 04:29:24 +000057#define MACVTAP_NUM_DEVS (1U << MINORBITS)
58static DEFINE_MUTEX(minor_lock);
59static DEFINE_IDR(minor_idr);
60
Shirley Ma97bc3632011-07-06 12:26:11 +000061#define GOODCOPY_LEN 128
Arnd Bergmann20d29d72010-01-30 12:24:26 +000062static struct class *macvtap_class;
63static struct cdev macvtap_cdev;
64
Arnd Bergmann501c7742010-02-18 05:46:50 +000065static const struct proto_ops macvtap_socket_ops;
66
Arnd Bergmann20d29d72010-01-30 12:24:26 +000067/*
68 * RCU usage:
Arnd Bergmann02df55d2010-02-18 05:45:36 +000069 * The macvtap_queue and the macvlan_dev are loosely coupled, the
70 * pointers from one to the other can only be read while rcu_read_lock
71 * or macvtap_lock is held.
Arnd Bergmann20d29d72010-01-30 12:24:26 +000072 *
Arnd Bergmann02df55d2010-02-18 05:45:36 +000073 * Both the file and the macvlan_dev hold a reference on the macvtap_queue
74 * through sock_hold(&q->sk). When the macvlan_dev goes away first,
75 * q->vlan becomes inaccessible. When the files gets closed,
76 * macvtap_get_queue() fails.
Arnd Bergmann20d29d72010-01-30 12:24:26 +000077 *
Arnd Bergmann02df55d2010-02-18 05:45:36 +000078 * There may still be references to the struct sock inside of the
79 * queue from outbound SKBs, but these never reference back to the
80 * file or the dev. The data structure is freed through __sk_free
81 * when both our references and any pending SKBs are gone.
Arnd Bergmann20d29d72010-01-30 12:24:26 +000082 */
83static DEFINE_SPINLOCK(macvtap_lock);
84
85/*
Krishna Kumar1565c7c2010-08-04 06:15:59 +000086 * get_slot: return a [unused/occupied] slot in vlan->taps[]:
87 * - if 'q' is NULL, return the first empty slot;
88 * - otherwise, return the slot this pointer occupies.
Arnd Bergmann20d29d72010-01-30 12:24:26 +000089 */
Krishna Kumar1565c7c2010-08-04 06:15:59 +000090static int get_slot(struct macvlan_dev *vlan, struct macvtap_queue *q)
91{
92 int i;
93
94 for (i = 0; i < MAX_MACVTAP_QUEUES; i++) {
95 if (rcu_dereference(vlan->taps[i]) == q)
96 return i;
97 }
98
99 /* Should never happen */
100 BUG_ON(1);
101}
102
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000103static int macvtap_set_queue(struct net_device *dev, struct file *file,
104 struct macvtap_queue *q)
105{
106 struct macvlan_dev *vlan = netdev_priv(dev);
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000107 int index;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000108 int err = -EBUSY;
109
110 spin_lock(&macvtap_lock);
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000111 if (vlan->numvtaps == MAX_MACVTAP_QUEUES)
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000112 goto out;
113
114 err = 0;
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000115 index = get_slot(vlan, NULL);
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000116 rcu_assign_pointer(q->vlan, vlan);
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000117 rcu_assign_pointer(vlan->taps[index], q);
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000118 sock_hold(&q->sk);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000119
120 q->file = file;
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000121 file->private_data = q;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000122
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000123 vlan->numvtaps++;
124
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000125out:
126 spin_unlock(&macvtap_lock);
127 return err;
128}
129
130/*
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000131 * The file owning the queue got closed, give up both
132 * the reference that the files holds as well as the
133 * one from the macvlan_dev if that still exists.
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000134 *
135 * Using the spinlock makes sure that we don't get
136 * to the queue again after destroying it.
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000137 */
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000138static void macvtap_put_queue(struct macvtap_queue *q)
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000139{
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000140 struct macvlan_dev *vlan;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000141
142 spin_lock(&macvtap_lock);
Eric Dumazet13707f92011-01-26 19:28:23 +0000143 vlan = rcu_dereference_protected(q->vlan,
144 lockdep_is_held(&macvtap_lock));
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000145 if (vlan) {
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000146 int index = get_slot(vlan, q);
147
Eric Dumazet2cfa5a02011-11-23 07:09:32 +0000148 RCU_INIT_POINTER(vlan->taps[index], NULL);
149 RCU_INIT_POINTER(q->vlan, NULL);
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000150 sock_put(&q->sk);
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000151 --vlan->numvtaps;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000152 }
153
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000154 spin_unlock(&macvtap_lock);
155
156 synchronize_rcu();
157 sock_put(&q->sk);
158}
159
160/*
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000161 * Select a queue based on the rxq of the device on which this packet
162 * arrived. If the incoming device is not mq, calculate a flow hash
163 * to select a queue. If all fails, find the first available queue.
164 * Cache vlan->numvtaps since it can become zero during the execution
165 * of this function.
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000166 */
167static struct macvtap_queue *macvtap_get_queue(struct net_device *dev,
168 struct sk_buff *skb)
169{
170 struct macvlan_dev *vlan = netdev_priv(dev);
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000171 struct macvtap_queue *tap = NULL;
172 int numvtaps = vlan->numvtaps;
173 __u32 rxq;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000174
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000175 if (!numvtaps)
176 goto out;
177
Krishna Kumaref0002b2011-11-23 22:17:14 +0000178 /* Check if we can use flow to select a queue */
179 rxq = skb_get_rxhash(skb);
180 if (rxq) {
181 tap = rcu_dereference(vlan->taps[rxq % numvtaps]);
182 if (tap)
183 goto out;
184 }
185
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000186 if (likely(skb_rx_queue_recorded(skb))) {
187 rxq = skb_get_rx_queue(skb);
188
189 while (unlikely(rxq >= numvtaps))
190 rxq -= numvtaps;
191
192 tap = rcu_dereference(vlan->taps[rxq]);
193 if (tap)
194 goto out;
195 }
196
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000197 /* Everything failed - find first available queue */
198 for (rxq = 0; rxq < MAX_MACVTAP_QUEUES; rxq++) {
199 tap = rcu_dereference(vlan->taps[rxq]);
200 if (tap)
201 break;
202 }
203
204out:
205 return tap;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000206}
207
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000208/*
209 * The net_device is going away, give up the reference
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000210 * that it holds on all queues and safely set the pointer
211 * from the queues to NULL.
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000212 */
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000213static void macvtap_del_queues(struct net_device *dev)
214{
215 struct macvlan_dev *vlan = netdev_priv(dev);
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000216 struct macvtap_queue *q, *qlist[MAX_MACVTAP_QUEUES];
217 int i, j = 0;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000218
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000219 /* macvtap_put_queue can free some slots, so go through all slots */
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000220 spin_lock(&macvtap_lock);
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000221 for (i = 0; i < MAX_MACVTAP_QUEUES && vlan->numvtaps; i++) {
Eric Dumazet13707f92011-01-26 19:28:23 +0000222 q = rcu_dereference_protected(vlan->taps[i],
223 lockdep_is_held(&macvtap_lock));
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000224 if (q) {
225 qlist[j++] = q;
Eric Dumazet2cfa5a02011-11-23 07:09:32 +0000226 RCU_INIT_POINTER(vlan->taps[i], NULL);
227 RCU_INIT_POINTER(q->vlan, NULL);
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000228 vlan->numvtaps--;
229 }
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000230 }
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000231 BUG_ON(vlan->numvtaps != 0);
Eric W. Biederman99f34b32011-10-20 04:26:01 +0000232 /* guarantee that any future macvtap_set_queue will fail */
233 vlan->numvtaps = MAX_MACVTAP_QUEUES;
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000234 spin_unlock(&macvtap_lock);
235
236 synchronize_rcu();
Krishna Kumar1565c7c2010-08-04 06:15:59 +0000237
238 for (--j; j >= 0; j--)
239 sock_put(&qlist[j]->sk);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000240}
241
242/*
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.
246 */
247static int macvtap_forward(struct net_device *dev, struct sk_buff *skb)
248{
249 struct macvtap_queue *q = macvtap_get_queue(dev, skb);
250 if (!q)
Herbert Xu8a357472010-07-21 21:44:31 +0000251 goto drop;
252
253 if (skb_queue_len(&q->sk.sk_receive_queue) >= dev->tx_queue_len)
254 goto drop;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000255
256 skb_queue_tail(&q->sk.sk_receive_queue, skb);
Eric Dumazet4a4771a2010-04-25 22:20:06 +0000257 wake_up_interruptible_poll(sk_sleep(&q->sk), POLLIN | POLLRDNORM | POLLRDBAND);
Herbert Xu8a357472010-07-21 21:44:31 +0000258 return NET_RX_SUCCESS;
259
260drop:
261 kfree_skb(skb);
262 return NET_RX_DROP;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000263}
264
265/*
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.
269 */
270static int macvtap_receive(struct sk_buff *skb)
271{
272 skb_push(skb, ETH_HLEN);
273 return macvtap_forward(skb->dev, skb);
274}
275
Eric W. Biedermane09eff72011-10-20 04:29:24 +0000276static int macvtap_get_minor(struct macvlan_dev *vlan)
277{
278 int retval = -ENOMEM;
279 int id;
280
281 mutex_lock(&minor_lock);
282 if (idr_pre_get(&minor_idr, GFP_KERNEL) == 0)
283 goto exit;
284
285 retval = idr_get_new_above(&minor_idr, vlan, 1, &id);
286 if (retval < 0) {
287 if (retval == -EAGAIN)
288 retval = -ENOMEM;
289 goto exit;
290 }
291 if (id < MACVTAP_NUM_DEVS) {
292 vlan->minor = id;
293 } else {
294 printk(KERN_ERR "too many macvtap devices\n");
295 retval = -EINVAL;
296 idr_remove(&minor_idr, id);
297 }
298exit:
299 mutex_unlock(&minor_lock);
300 return retval;
301}
302
303static void macvtap_free_minor(struct macvlan_dev *vlan)
304{
305 mutex_lock(&minor_lock);
306 if (vlan->minor) {
307 idr_remove(&minor_idr, vlan->minor);
308 vlan->minor = 0;
309 }
310 mutex_unlock(&minor_lock);
311}
312
313static struct net_device *dev_get_by_macvtap_minor(int minor)
314{
315 struct net_device *dev = NULL;
316 struct macvlan_dev *vlan;
317
318 mutex_lock(&minor_lock);
319 vlan = idr_find(&minor_idr, minor);
320 if (vlan) {
321 dev = vlan->dev;
322 dev_hold(dev);
323 }
324 mutex_unlock(&minor_lock);
325 return dev;
326}
327
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000328static int macvtap_newlink(struct net *src_net,
329 struct net_device *dev,
330 struct nlattr *tb[],
331 struct nlattr *data[])
332{
Eric W. Biederman9bf19072011-10-20 04:28:46 +0000333 /* Don't put anything that may fail after macvlan_common_newlink
334 * because we can't undo what it does.
335 */
336 return macvlan_common_newlink(src_net, dev, tb, data,
337 macvtap_receive, macvtap_forward);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000338}
339
340static void macvtap_dellink(struct net_device *dev,
341 struct list_head *head)
342{
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000343 macvtap_del_queues(dev);
344 macvlan_dellink(dev, head);
345}
346
Herbert Xu8a357472010-07-21 21:44:31 +0000347static void macvtap_setup(struct net_device *dev)
348{
349 macvlan_common_setup(dev);
350 dev->tx_queue_len = TUN_READQ_SIZE;
351}
352
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000353static struct rtnl_link_ops macvtap_link_ops __read_mostly = {
354 .kind = "macvtap",
Herbert Xu8a357472010-07-21 21:44:31 +0000355 .setup = macvtap_setup,
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000356 .newlink = macvtap_newlink,
357 .dellink = macvtap_dellink,
358};
359
360
361static void macvtap_sock_write_space(struct sock *sk)
362{
Eric Dumazet43815482010-04-29 11:01:49 +0000363 wait_queue_head_t *wqueue;
364
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000365 if (!sock_writeable(sk) ||
366 !test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags))
367 return;
368
Eric Dumazet43815482010-04-29 11:01:49 +0000369 wqueue = sk_sleep(sk);
370 if (wqueue && waitqueue_active(wqueue))
371 wake_up_interruptible_poll(wqueue, POLLOUT | POLLWRNORM | POLLWRBAND);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000372}
373
Eric W. Biederman2259fef2011-10-20 04:27:24 +0000374static void macvtap_sock_destruct(struct sock *sk)
375{
376 skb_queue_purge(&sk->sk_receive_queue);
377}
378
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000379static int macvtap_open(struct inode *inode, struct file *file)
380{
381 struct net *net = current->nsproxy->net_ns;
Eric W. Biedermane09eff72011-10-20 04:29:24 +0000382 struct net_device *dev = dev_get_by_macvtap_minor(iminor(inode));
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000383 struct macvtap_queue *q;
384 int err;
385
386 err = -ENODEV;
387 if (!dev)
388 goto out;
389
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000390 err = -ENOMEM;
391 q = (struct macvtap_queue *)sk_alloc(net, AF_UNSPEC, GFP_KERNEL,
392 &macvtap_proto);
393 if (!q)
394 goto out;
395
Eric Dumazet43815482010-04-29 11:01:49 +0000396 q->sock.wq = &q->wq;
397 init_waitqueue_head(&q->wq.wait);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000398 q->sock.type = SOCK_RAW;
399 q->sock.state = SS_CONNECTED;
Arnd Bergmann501c7742010-02-18 05:46:50 +0000400 q->sock.file = file;
401 q->sock.ops = &macvtap_socket_ops;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000402 sock_init_data(&q->sock, &q->sk);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000403 q->sk.sk_write_space = macvtap_sock_write_space;
Eric W. Biederman2259fef2011-10-20 04:27:24 +0000404 q->sk.sk_destruct = macvtap_sock_destruct;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000405 q->flags = IFF_VNET_HDR | IFF_NO_PI | IFF_TAP;
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +0300406 q->vnet_hdr_sz = sizeof(struct virtio_net_hdr);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000407
Shirley Ma97bc3632011-07-06 12:26:11 +0000408 /*
409 * so far only KVM virtio_net uses macvtap, enable zero copy between
410 * guest kernel and host kernel when lower device supports zerocopy
Eric W. Biederman047af9cf2011-10-20 04:26:39 +0000411 *
412 * The macvlan supports zerocopy iff the lower device supports zero
413 * copy so we don't have to look at the lower device directly.
Shirley Ma97bc3632011-07-06 12:26:11 +0000414 */
Eric W. Biederman047af9cf2011-10-20 04:26:39 +0000415 if ((dev->features & NETIF_F_HIGHDMA) && (dev->features & NETIF_F_SG))
416 sock_set_flag(&q->sk, SOCK_ZEROCOPY);
Shirley Ma97bc3632011-07-06 12:26:11 +0000417
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000418 err = macvtap_set_queue(dev, file, q);
419 if (err)
420 sock_put(&q->sk);
421
422out:
423 if (dev)
424 dev_put(dev);
425
426 return err;
427}
428
429static int macvtap_release(struct inode *inode, struct file *file)
430{
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000431 struct macvtap_queue *q = file->private_data;
432 macvtap_put_queue(q);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000433 return 0;
434}
435
436static unsigned int macvtap_poll(struct file *file, poll_table * wait)
437{
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000438 struct macvtap_queue *q = file->private_data;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000439 unsigned int mask = POLLERR;
440
441 if (!q)
442 goto out;
443
444 mask = 0;
Eric Dumazet43815482010-04-29 11:01:49 +0000445 poll_wait(file, &q->wq.wait, wait);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000446
447 if (!skb_queue_empty(&q->sk.sk_receive_queue))
448 mask |= POLLIN | POLLRDNORM;
449
450 if (sock_writeable(&q->sk) ||
451 (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &q->sock.flags) &&
452 sock_writeable(&q->sk)))
453 mask |= POLLOUT | POLLWRNORM;
454
455out:
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000456 return mask;
457}
458
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000459static inline struct sk_buff *macvtap_alloc_skb(struct sock *sk, size_t prepad,
460 size_t len, size_t linear,
461 int noblock, int *err)
462{
463 struct sk_buff *skb;
464
465 /* Under a page? Don't bother with paged skb. */
466 if (prepad + len < PAGE_SIZE || !linear)
467 linear = len;
468
469 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
470 err);
471 if (!skb)
472 return NULL;
473
474 skb_reserve(skb, prepad);
475 skb_put(skb, linear);
476 skb->data_len = len - linear;
477 skb->len += len - linear;
478
479 return skb;
480}
481
Shirley Ma97bc3632011-07-06 12:26:11 +0000482/* set skb frags from iovec, this can move to core network code for reuse */
483static int zerocopy_sg_from_iovec(struct sk_buff *skb, const struct iovec *from,
484 int offset, size_t count)
485{
486 int len = iov_length(from, count) - offset;
487 int copy = skb_headlen(skb);
488 int size, offset1 = 0;
489 int i = 0;
Shirley Ma97bc3632011-07-06 12:26:11 +0000490
491 /* Skip over from offset */
492 while (count && (offset >= from->iov_len)) {
493 offset -= from->iov_len;
494 ++from;
495 --count;
496 }
497
498 /* copy up to skb headlen */
499 while (count && (copy > 0)) {
500 size = min_t(unsigned int, copy, from->iov_len - offset);
501 if (copy_from_user(skb->data + offset1, from->iov_base + offset,
502 size))
503 return -EFAULT;
504 if (copy > size) {
505 ++from;
506 --count;
507 }
508 copy -= size;
509 offset1 += size;
510 offset = 0;
511 }
512
513 if (len == offset1)
514 return 0;
515
516 while (count--) {
517 struct page *page[MAX_SKB_FRAGS];
518 int num_pages;
519 unsigned long base;
520
521 len = from->iov_len - offset1;
522 if (!len) {
523 offset1 = 0;
524 ++from;
525 continue;
526 }
527 base = (unsigned long)from->iov_base + offset1;
528 size = ((base & ~PAGE_MASK) + len + ~PAGE_MASK) >> PAGE_SHIFT;
529 num_pages = get_user_pages_fast(base, size, 0, &page[i]);
530 if ((num_pages != size) ||
531 (num_pages > MAX_SKB_FRAGS - skb_shinfo(skb)->nr_frags))
532 /* put_page is in skb free */
533 return -EFAULT;
534 skb->data_len += len;
535 skb->len += len;
536 skb->truesize += len;
537 atomic_add(len, &skb->sk->sk_wmem_alloc);
538 while (len) {
Jason Wang653fc912011-09-18 23:48:31 +0000539 int off = base & ~PAGE_MASK;
540 int size = min_t(int, len, PAGE_SIZE - off);
541 __skb_fill_page_desc(skb, i, page[i], off, size);
Shirley Ma97bc3632011-07-06 12:26:11 +0000542 skb_shinfo(skb)->nr_frags++;
543 /* increase sk_wmem_alloc */
Jason Wang653fc912011-09-18 23:48:31 +0000544 base += size;
545 len -= size;
Shirley Ma97bc3632011-07-06 12:26:11 +0000546 i++;
547 }
548 offset1 = 0;
549 ++from;
550 }
551 return 0;
552}
553
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000554/*
555 * macvtap_skb_from_vnet_hdr and macvtap_skb_to_vnet_hdr should
556 * be shared with the tun/tap driver.
557 */
558static int macvtap_skb_from_vnet_hdr(struct sk_buff *skb,
559 struct virtio_net_hdr *vnet_hdr)
560{
561 unsigned short gso_type = 0;
562 if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
563 switch (vnet_hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
564 case VIRTIO_NET_HDR_GSO_TCPV4:
565 gso_type = SKB_GSO_TCPV4;
566 break;
567 case VIRTIO_NET_HDR_GSO_TCPV6:
568 gso_type = SKB_GSO_TCPV6;
569 break;
570 case VIRTIO_NET_HDR_GSO_UDP:
571 gso_type = SKB_GSO_UDP;
572 break;
573 default:
574 return -EINVAL;
575 }
576
577 if (vnet_hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN)
578 gso_type |= SKB_GSO_TCP_ECN;
579
580 if (vnet_hdr->gso_size == 0)
581 return -EINVAL;
582 }
583
584 if (vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
585 if (!skb_partial_csum_set(skb, vnet_hdr->csum_start,
586 vnet_hdr->csum_offset))
587 return -EINVAL;
588 }
589
590 if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
591 skb_shinfo(skb)->gso_size = vnet_hdr->gso_size;
592 skb_shinfo(skb)->gso_type = gso_type;
593
594 /* Header must be checked, and gso_segs computed. */
595 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
596 skb_shinfo(skb)->gso_segs = 0;
597 }
598 return 0;
599}
600
601static int macvtap_skb_to_vnet_hdr(const struct sk_buff *skb,
602 struct virtio_net_hdr *vnet_hdr)
603{
604 memset(vnet_hdr, 0, sizeof(*vnet_hdr));
605
606 if (skb_is_gso(skb)) {
607 struct skb_shared_info *sinfo = skb_shinfo(skb);
608
609 /* This is a hint as to how much should be linear. */
610 vnet_hdr->hdr_len = skb_headlen(skb);
611 vnet_hdr->gso_size = sinfo->gso_size;
612 if (sinfo->gso_type & SKB_GSO_TCPV4)
613 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
614 else if (sinfo->gso_type & SKB_GSO_TCPV6)
615 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
616 else if (sinfo->gso_type & SKB_GSO_UDP)
617 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
618 else
619 BUG();
620 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
621 vnet_hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
622 } else
623 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
624
625 if (skb->ip_summed == CHECKSUM_PARTIAL) {
626 vnet_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
Michał Mirosław55508d62010-12-14 15:24:08 +0000627 vnet_hdr->csum_start = skb_checksum_start_offset(skb);
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000628 vnet_hdr->csum_offset = skb->csum_offset;
Jason Wang10a8d942011-06-10 00:56:17 +0000629 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
630 vnet_hdr->flags = VIRTIO_NET_HDR_F_DATA_VALID;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000631 } /* else everything is zero */
632
633 return 0;
634}
635
636
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000637/* Get packet from user space buffer */
Shirley Ma97bc3632011-07-06 12:26:11 +0000638static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
639 const struct iovec *iv, unsigned long total_len,
640 size_t count, int noblock)
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000641{
642 struct sk_buff *skb;
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000643 struct macvlan_dev *vlan;
Shirley Ma97bc3632011-07-06 12:26:11 +0000644 unsigned long len = total_len;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000645 int err;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000646 struct virtio_net_hdr vnet_hdr = { 0 };
647 int vnet_hdr_len = 0;
Shirley Ma97bc3632011-07-06 12:26:11 +0000648 int copylen;
649 bool zerocopy = false;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000650
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000651 if (q->flags & IFF_VNET_HDR) {
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +0300652 vnet_hdr_len = q->vnet_hdr_sz;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000653
654 err = -EINVAL;
Nicolas Kaiserce3c8692011-03-04 13:49:41 +0000655 if (len < vnet_hdr_len)
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000656 goto err;
Nicolas Kaiserce3c8692011-03-04 13:49:41 +0000657 len -= vnet_hdr_len;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000658
659 err = memcpy_fromiovecend((void *)&vnet_hdr, iv, 0,
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +0300660 sizeof(vnet_hdr));
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000661 if (err < 0)
662 goto err;
663 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
664 vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
665 vnet_hdr.hdr_len)
666 vnet_hdr.hdr_len = vnet_hdr.csum_start +
667 vnet_hdr.csum_offset + 2;
668 err = -EINVAL;
669 if (vnet_hdr.hdr_len > len)
670 goto err;
671 }
672
673 err = -EINVAL;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000674 if (unlikely(len < ETH_HLEN))
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000675 goto err;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000676
Shirley Ma97bc3632011-07-06 12:26:11 +0000677 if (m && m->msg_control && sock_flag(&q->sk, SOCK_ZEROCOPY))
678 zerocopy = true;
679
680 if (zerocopy) {
681 /* There are 256 bytes to be copied in skb, so there is enough
682 * room for skb expand head in case it is used.
683 * The rest buffer is mapped from userspace.
684 */
685 copylen = vnet_hdr.hdr_len;
686 if (!copylen)
687 copylen = GOODCOPY_LEN;
688 } else
689 copylen = len;
690
691 skb = macvtap_alloc_skb(&q->sk, NET_IP_ALIGN, copylen,
692 vnet_hdr.hdr_len, noblock, &err);
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000693 if (!skb)
694 goto err;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000695
Shirley Ma97bc3632011-07-06 12:26:11 +0000696 if (zerocopy) {
697 err = zerocopy_sg_from_iovec(skb, iv, vnet_hdr_len, count);
698 skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY;
699 } else
700 err = skb_copy_datagram_from_iovec(skb, 0, iv, vnet_hdr_len,
701 len);
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000702 if (err)
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000703 goto err_kfree;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000704
705 skb_set_network_header(skb, ETH_HLEN);
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000706 skb_reset_mac_header(skb);
707 skb->protocol = eth_hdr(skb)->h_proto;
708
709 if (vnet_hdr_len) {
710 err = macvtap_skb_from_vnet_hdr(skb, &vnet_hdr);
711 if (err)
712 goto err_kfree;
713 }
714
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000715 rcu_read_lock_bh();
Eric Dumazet13707f92011-01-26 19:28:23 +0000716 vlan = rcu_dereference_bh(q->vlan);
Shirley Ma97bc3632011-07-06 12:26:11 +0000717 /* copy skb_ubuf_info for callback when skb has no error */
718 if (zerocopy)
719 skb_shinfo(skb)->destructor_arg = m->msg_control;
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000720 if (vlan)
721 macvlan_start_xmit(skb, vlan->dev);
722 else
723 kfree_skb(skb);
724 rcu_read_unlock_bh();
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000725
Shirley Ma97bc3632011-07-06 12:26:11 +0000726 return total_len;
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000727
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000728err_kfree:
729 kfree_skb(skb);
730
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000731err:
732 rcu_read_lock_bh();
Eric Dumazet13707f92011-01-26 19:28:23 +0000733 vlan = rcu_dereference_bh(q->vlan);
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000734 if (vlan)
Eric Dumazet1ac9ad12011-01-12 12:13:14 +0000735 vlan->dev->stats.tx_dropped++;
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000736 rcu_read_unlock_bh();
737
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000738 return err;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000739}
740
741static ssize_t macvtap_aio_write(struct kiocb *iocb, const struct iovec *iv,
742 unsigned long count, loff_t pos)
743{
744 struct file *file = iocb->ki_filp;
745 ssize_t result = -ENOLINK;
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000746 struct macvtap_queue *q = file->private_data;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000747
Shirley Ma97bc3632011-07-06 12:26:11 +0000748 result = macvtap_get_user(q, NULL, iv, iov_length(iv, count), count,
749 file->f_flags & O_NONBLOCK);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000750 return result;
751}
752
753/* Put packet to the user space buffer */
754static ssize_t macvtap_put_user(struct macvtap_queue *q,
755 const struct sk_buff *skb,
756 const struct iovec *iv, int len)
757{
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000758 struct macvlan_dev *vlan;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000759 int ret;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000760 int vnet_hdr_len = 0;
761
762 if (q->flags & IFF_VNET_HDR) {
763 struct virtio_net_hdr vnet_hdr;
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +0300764 vnet_hdr_len = q->vnet_hdr_sz;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000765 if ((len -= vnet_hdr_len) < 0)
766 return -EINVAL;
767
768 ret = macvtap_skb_to_vnet_hdr(skb, &vnet_hdr);
769 if (ret)
770 return ret;
771
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +0300772 if (memcpy_toiovecend(iv, (void *)&vnet_hdr, 0, sizeof(vnet_hdr)))
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000773 return -EFAULT;
774 }
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000775
776 len = min_t(int, skb->len, len);
777
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000778 ret = skb_copy_datagram_const_iovec(skb, 0, iv, vnet_hdr_len, len);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000779
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000780 rcu_read_lock_bh();
Eric Dumazet13707f92011-01-26 19:28:23 +0000781 vlan = rcu_dereference_bh(q->vlan);
Arnd Bergmann501c7742010-02-18 05:46:50 +0000782 if (vlan)
783 macvlan_count_rx(vlan, len, ret == 0, 0);
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000784 rcu_read_unlock_bh();
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000785
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000786 return ret ? ret : (len + vnet_hdr_len);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000787}
788
Arnd Bergmann501c7742010-02-18 05:46:50 +0000789static ssize_t macvtap_do_read(struct macvtap_queue *q, struct kiocb *iocb,
790 const struct iovec *iv, unsigned long len,
791 int noblock)
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000792{
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000793 DECLARE_WAITQUEUE(wait, current);
794 struct sk_buff *skb;
Arnd Bergmann501c7742010-02-18 05:46:50 +0000795 ssize_t ret = 0;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000796
Eric Dumazet4a4771a2010-04-25 22:20:06 +0000797 add_wait_queue(sk_sleep(&q->sk), &wait);
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000798 while (len) {
799 current->state = TASK_INTERRUPTIBLE;
800
801 /* Read frames from the queue */
802 skb = skb_dequeue(&q->sk.sk_receive_queue);
803 if (!skb) {
Arnd Bergmann501c7742010-02-18 05:46:50 +0000804 if (noblock) {
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000805 ret = -EAGAIN;
806 break;
807 }
808 if (signal_pending(current)) {
809 ret = -ERESTARTSYS;
810 break;
811 }
812 /* Nothing to read, let's sleep */
813 schedule();
814 continue;
815 }
816 ret = macvtap_put_user(q, skb, iv, len);
817 kfree_skb(skb);
818 break;
819 }
820
821 current->state = TASK_RUNNING;
Eric Dumazet4a4771a2010-04-25 22:20:06 +0000822 remove_wait_queue(sk_sleep(&q->sk), &wait);
Arnd Bergmann501c7742010-02-18 05:46:50 +0000823 return ret;
824}
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000825
Arnd Bergmann501c7742010-02-18 05:46:50 +0000826static ssize_t macvtap_aio_read(struct kiocb *iocb, const struct iovec *iv,
827 unsigned long count, loff_t pos)
828{
829 struct file *file = iocb->ki_filp;
830 struct macvtap_queue *q = file->private_data;
831 ssize_t len, ret = 0;
832
833 len = iov_length(iv, count);
834 if (len < 0) {
835 ret = -EINVAL;
836 goto out;
837 }
838
839 ret = macvtap_do_read(q, iocb, iv, len, file->f_flags & O_NONBLOCK);
840 ret = min_t(ssize_t, ret, len); /* XXX copied from tun.c. Why? */
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000841out:
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000842 return ret;
843}
844
845/*
846 * provide compatibility with generic tun/tap interface
847 */
848static long macvtap_ioctl(struct file *file, unsigned int cmd,
849 unsigned long arg)
850{
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000851 struct macvtap_queue *q = file->private_data;
852 struct macvlan_dev *vlan;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000853 void __user *argp = (void __user *)arg;
854 struct ifreq __user *ifr = argp;
855 unsigned int __user *up = argp;
856 unsigned int u;
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +0300857 int __user *sp = argp;
858 int s;
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000859 int ret;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000860
861 switch (cmd) {
862 case TUNSETIFF:
863 /* ignore the name, just look at flags */
864 if (get_user(u, &ifr->ifr_flags))
865 return -EFAULT;
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000866
867 ret = 0;
868 if ((u & ~IFF_VNET_HDR) != (IFF_NO_PI | IFF_TAP))
869 ret = -EINVAL;
870 else
871 q->flags = u;
872
873 return ret;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000874
875 case TUNGETIFF:
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000876 rcu_read_lock_bh();
Eric Dumazet13707f92011-01-26 19:28:23 +0000877 vlan = rcu_dereference_bh(q->vlan);
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000878 if (vlan)
879 dev_hold(vlan->dev);
880 rcu_read_unlock_bh();
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000881
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000882 if (!vlan)
883 return -ENOLINK;
884
885 ret = 0;
Eric Dumazet13707f92011-01-26 19:28:23 +0000886 if (copy_to_user(&ifr->ifr_name, vlan->dev->name, IFNAMSIZ) ||
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000887 put_user(q->flags, &ifr->ifr_flags))
Arnd Bergmann02df55d2010-02-18 05:45:36 +0000888 ret = -EFAULT;
889 dev_put(vlan->dev);
890 return ret;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000891
892 case TUNGETFEATURES:
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000893 if (put_user(IFF_TAP | IFF_NO_PI | IFF_VNET_HDR, up))
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000894 return -EFAULT;
895 return 0;
896
897 case TUNSETSNDBUF:
898 if (get_user(u, up))
899 return -EFAULT;
900
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000901 q->sk.sk_sndbuf = u;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000902 return 0;
903
Michael S. Tsirkin55afbd02010-04-29 13:50:48 +0300904 case TUNGETVNETHDRSZ:
905 s = q->vnet_hdr_sz;
906 if (put_user(s, sp))
907 return -EFAULT;
908 return 0;
909
910 case TUNSETVNETHDRSZ:
911 if (get_user(s, sp))
912 return -EFAULT;
913 if (s < (int)sizeof(struct virtio_net_hdr))
914 return -EINVAL;
915
916 q->vnet_hdr_sz = s;
917 return 0;
918
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000919 case TUNSETOFFLOAD:
920 /* let the user check for future flags */
921 if (arg & ~(TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6 |
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000922 TUN_F_TSO_ECN | TUN_F_UFO))
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000923 return -EINVAL;
924
Arnd Bergmannb9fb9ee2010-02-18 05:48:17 +0000925 /* TODO: only accept frames with the features that
926 got enabled for forwarded frames */
927 if (!(q->flags & IFF_VNET_HDR))
928 return -EINVAL;
Arnd Bergmann20d29d72010-01-30 12:24:26 +0000929 return 0;
930
931 default:
932 return -EINVAL;
933 }
934}
935
936#ifdef CONFIG_COMPAT
937static long macvtap_compat_ioctl(struct file *file, unsigned int cmd,
938 unsigned long arg)
939{
940 return macvtap_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
941}
942#endif
943
944static const struct file_operations macvtap_fops = {
945 .owner = THIS_MODULE,
946 .open = macvtap_open,
947 .release = macvtap_release,
948 .aio_read = macvtap_aio_read,
949 .aio_write = macvtap_aio_write,
950 .poll = macvtap_poll,
951 .llseek = no_llseek,
952 .unlocked_ioctl = macvtap_ioctl,
953#ifdef CONFIG_COMPAT
954 .compat_ioctl = macvtap_compat_ioctl,
955#endif
956};
957
Arnd Bergmann501c7742010-02-18 05:46:50 +0000958static int macvtap_sendmsg(struct kiocb *iocb, struct socket *sock,
959 struct msghdr *m, size_t total_len)
960{
961 struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock);
Shirley Ma97bc3632011-07-06 12:26:11 +0000962 return macvtap_get_user(q, m, m->msg_iov, total_len, m->msg_iovlen,
Arnd Bergmann501c7742010-02-18 05:46:50 +0000963 m->msg_flags & MSG_DONTWAIT);
964}
965
966static int macvtap_recvmsg(struct kiocb *iocb, struct socket *sock,
967 struct msghdr *m, size_t total_len,
968 int flags)
969{
970 struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock);
971 int ret;
972 if (flags & ~(MSG_DONTWAIT|MSG_TRUNC))
973 return -EINVAL;
974 ret = macvtap_do_read(q, iocb, m->msg_iov, total_len,
975 flags & MSG_DONTWAIT);
976 if (ret > total_len) {
977 m->msg_flags |= MSG_TRUNC;
978 ret = flags & MSG_TRUNC ? ret : total_len;
979 }
980 return ret;
981}
982
983/* Ops structure to mimic raw sockets with tun */
984static const struct proto_ops macvtap_socket_ops = {
985 .sendmsg = macvtap_sendmsg,
986 .recvmsg = macvtap_recvmsg,
987};
988
989/* Get an underlying socket object from tun file. Returns error unless file is
990 * attached to a device. The returned object works like a packet socket, it
991 * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for
992 * holding a reference to the file for as long as the socket is in use. */
993struct socket *macvtap_get_socket(struct file *file)
994{
995 struct macvtap_queue *q;
996 if (file->f_op != &macvtap_fops)
997 return ERR_PTR(-EINVAL);
998 q = file->private_data;
999 if (!q)
1000 return ERR_PTR(-EBADFD);
1001 return &q->sock;
1002}
1003EXPORT_SYMBOL_GPL(macvtap_get_socket);
1004
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001005static int macvtap_device_event(struct notifier_block *unused,
1006 unsigned long event, void *ptr)
1007{
1008 struct net_device *dev = ptr;
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001009 struct macvlan_dev *vlan;
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001010 struct device *classdev;
1011 dev_t devt;
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001012 int err;
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001013
1014 if (dev->rtnl_link_ops != &macvtap_link_ops)
1015 return NOTIFY_DONE;
1016
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001017 vlan = netdev_priv(dev);
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001018
1019 switch (event) {
1020 case NETDEV_REGISTER:
1021 /* Create the device node here after the network device has
1022 * been registered but before register_netdevice has
1023 * finished running.
1024 */
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001025 err = macvtap_get_minor(vlan);
1026 if (err)
1027 return notifier_from_errno(err);
1028
1029 devt = MKDEV(MAJOR(macvtap_major), vlan->minor);
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001030 classdev = device_create(macvtap_class, &dev->dev, devt,
1031 dev, "tap%d", dev->ifindex);
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001032 if (IS_ERR(classdev)) {
1033 macvtap_free_minor(vlan);
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001034 return notifier_from_errno(PTR_ERR(classdev));
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001035 }
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001036 break;
1037 case NETDEV_UNREGISTER:
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001038 devt = MKDEV(MAJOR(macvtap_major), vlan->minor);
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001039 device_destroy(macvtap_class, devt);
Eric W. Biedermane09eff72011-10-20 04:29:24 +00001040 macvtap_free_minor(vlan);
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001041 break;
1042 }
1043
1044 return NOTIFY_DONE;
1045}
1046
1047static struct notifier_block macvtap_notifier_block __read_mostly = {
1048 .notifier_call = macvtap_device_event,
1049};
1050
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001051static int macvtap_init(void)
1052{
1053 int err;
1054
1055 err = alloc_chrdev_region(&macvtap_major, 0,
1056 MACVTAP_NUM_DEVS, "macvtap");
1057 if (err)
1058 goto out1;
1059
1060 cdev_init(&macvtap_cdev, &macvtap_fops);
1061 err = cdev_add(&macvtap_cdev, macvtap_major, MACVTAP_NUM_DEVS);
1062 if (err)
1063 goto out2;
1064
1065 macvtap_class = class_create(THIS_MODULE, "macvtap");
1066 if (IS_ERR(macvtap_class)) {
1067 err = PTR_ERR(macvtap_class);
1068 goto out3;
1069 }
1070
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001071 err = register_netdevice_notifier(&macvtap_notifier_block);
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001072 if (err)
1073 goto out4;
1074
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001075 err = macvlan_link_register(&macvtap_link_ops);
1076 if (err)
1077 goto out5;
1078
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001079 return 0;
1080
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001081out5:
1082 unregister_netdevice_notifier(&macvtap_notifier_block);
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001083out4:
1084 class_unregister(macvtap_class);
1085out3:
1086 cdev_del(&macvtap_cdev);
1087out2:
1088 unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
1089out1:
1090 return err;
1091}
1092module_init(macvtap_init);
1093
1094static void macvtap_exit(void)
1095{
1096 rtnl_link_unregister(&macvtap_link_ops);
Eric W. Biederman9bf19072011-10-20 04:28:46 +00001097 unregister_netdevice_notifier(&macvtap_notifier_block);
Arnd Bergmann20d29d72010-01-30 12:24:26 +00001098 class_unregister(macvtap_class);
1099 cdev_del(&macvtap_cdev);
1100 unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
1101}
1102module_exit(macvtap_exit);
1103
1104MODULE_ALIAS_RTNL_LINK("macvtap");
1105MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
1106MODULE_LICENSE("GPL");