mei: mask interrupt set bit on clean reset bit
[linux-2.6-block.git] / drivers / net / macvtap.c
CommitLineData
20d29d7a
AB
1#include <linux/etherdevice.h>
2#include <linux/if_macvlan.h>
f09e2249 3#include <linux/if_vlan.h>
20d29d7a
AB
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>
5a0e3ad6 13#include <linux/slab.h>
20d29d7a
AB
14#include <linux/wait.h>
15#include <linux/cdev.h>
40401530 16#include <linux/idr.h>
20d29d7a 17#include <linux/fs.h>
6c36d2e2 18#include <linux/uio.h>
20d29d7a 19
5188cd44 20#include <net/ipv6.h>
20d29d7a
AB
21#include <net/net_namespace.h>
22#include <net/rtnetlink.h>
23#include <net/sock.h>
b9fb9ee0 24#include <linux/virtio_net.h>
20d29d7a
AB
25
26/*
27 * A macvtap queue is the central object of this driver, it connects
28 * an open character device to a macvlan interface. There can be
29 * multiple queues on one interface, which map back to queues
30 * implemented in hardware on the underlying device.
31 *
32 * macvtap_proto is used to allocate queues through the sock allocation
33 * mechanism.
34 *
20d29d7a
AB
35 */
36struct macvtap_queue {
37 struct sock sk;
38 struct socket sock;
43815482 39 struct socket_wq wq;
55afbd08 40 int vnet_hdr_sz;
13707f9e 41 struct macvlan_dev __rcu *vlan;
20d29d7a 42 struct file *file;
b9fb9ee0 43 unsigned int flags;
376b1aab 44 u16 queue_index;
815f236d
JW
45 bool enabled;
46 struct list_head next;
20d29d7a
AB
47};
48
01b07fb3
MT
49#define MACVTAP_FEATURES (IFF_VNET_HDR | IFF_MULTI_QUEUE)
50
51#define MACVTAP_VNET_LE 0x80000000
6ae7feb3
MT
52
53static inline u16 macvtap16_to_cpu(struct macvtap_queue *q, __virtio16 val)
54{
01b07fb3 55 return __virtio16_to_cpu(q->flags & MACVTAP_VNET_LE, val);
6ae7feb3
MT
56}
57
58static inline __virtio16 cpu_to_macvtap16(struct macvtap_queue *q, u16 val)
59{
01b07fb3 60 return __cpu_to_virtio16(q->flags & MACVTAP_VNET_LE, val);
6ae7feb3
MT
61}
62
20d29d7a
AB
63static struct proto macvtap_proto = {
64 .name = "macvtap",
65 .owner = THIS_MODULE,
66 .obj_size = sizeof (struct macvtap_queue),
67};
68
69/*
e09eff7f 70 * Variables for dealing with macvtaps device numbers.
20d29d7a 71 */
1ebed71a 72static dev_t macvtap_major;
e09eff7f
EB
73#define MACVTAP_NUM_DEVS (1U << MINORBITS)
74static DEFINE_MUTEX(minor_lock);
75static DEFINE_IDR(minor_idr);
76
97bc3633 77#define GOODCOPY_LEN 128
20d29d7a
AB
78static struct class *macvtap_class;
79static struct cdev macvtap_cdev;
80
501c774c
AB
81static const struct proto_ops macvtap_socket_ops;
82
2be5c767 83#define TUN_OFFLOADS (NETIF_F_HW_CSUM | NETIF_F_TSO_ECN | NETIF_F_TSO | \
3d0ad094 84 NETIF_F_TSO6)
2be5c767 85#define RX_OFFLOADS (NETIF_F_GRO | NETIF_F_LRO)
a567dd62
VY
86#define TAP_FEATURES (NETIF_F_GSO | NETIF_F_SG)
87
6acf54f1
VY
88static struct macvlan_dev *macvtap_get_vlan_rcu(const struct net_device *dev)
89{
90 return rcu_dereference(dev->rx_handler_data);
91}
92
20d29d7a
AB
93/*
94 * RCU usage:
02df55d2
AB
95 * The macvtap_queue and the macvlan_dev are loosely coupled, the
96 * pointers from one to the other can only be read while rcu_read_lock
441ac0fc 97 * or rtnl is held.
20d29d7a 98 *
02df55d2
AB
99 * Both the file and the macvlan_dev hold a reference on the macvtap_queue
100 * through sock_hold(&q->sk). When the macvlan_dev goes away first,
101 * q->vlan becomes inaccessible. When the files gets closed,
102 * macvtap_get_queue() fails.
20d29d7a 103 *
02df55d2
AB
104 * There may still be references to the struct sock inside of the
105 * queue from outbound SKBs, but these never reference back to the
106 * file or the dev. The data structure is freed through __sk_free
107 * when both our references and any pending SKBs are gone.
20d29d7a 108 */
20d29d7a 109
815f236d 110static int macvtap_enable_queue(struct net_device *dev, struct file *file,
20d29d7a 111 struct macvtap_queue *q)
815f236d
JW
112{
113 struct macvlan_dev *vlan = netdev_priv(dev);
114 int err = -EINVAL;
115
441ac0fc 116 ASSERT_RTNL();
815f236d
JW
117
118 if (q->enabled)
119 goto out;
120
121 err = 0;
122 rcu_assign_pointer(vlan->taps[vlan->numvtaps], q);
123 q->queue_index = vlan->numvtaps;
124 q->enabled = true;
125
126 vlan->numvtaps++;
127out:
815f236d
JW
128 return err;
129}
130
40b8fe45 131/* Requires RTNL */
815f236d
JW
132static int macvtap_set_queue(struct net_device *dev, struct file *file,
133 struct macvtap_queue *q)
20d29d7a
AB
134{
135 struct macvlan_dev *vlan = netdev_priv(dev);
20d29d7a 136
815f236d 137 if (vlan->numqueues == MAX_MACVTAP_QUEUES)
40b8fe45 138 return -EBUSY;
20d29d7a 139
02df55d2 140 rcu_assign_pointer(q->vlan, vlan);
376b1aab 141 rcu_assign_pointer(vlan->taps[vlan->numvtaps], q);
02df55d2 142 sock_hold(&q->sk);
20d29d7a
AB
143
144 q->file = file;
376b1aab 145 q->queue_index = vlan->numvtaps;
815f236d 146 q->enabled = true;
02df55d2 147 file->private_data = q;
815f236d 148 list_add_tail(&q->next, &vlan->queue_list);
20d29d7a 149
1565c7c1 150 vlan->numvtaps++;
815f236d 151 vlan->numqueues++;
1565c7c1 152
40b8fe45 153 return 0;
20d29d7a
AB
154}
155
441ac0fc 156static int macvtap_disable_queue(struct macvtap_queue *q)
815f236d
JW
157{
158 struct macvlan_dev *vlan;
159 struct macvtap_queue *nq;
160
441ac0fc 161 ASSERT_RTNL();
815f236d
JW
162 if (!q->enabled)
163 return -EINVAL;
164
441ac0fc
VY
165 vlan = rtnl_dereference(q->vlan);
166
815f236d
JW
167 if (vlan) {
168 int index = q->queue_index;
169 BUG_ON(index >= vlan->numvtaps);
441ac0fc 170 nq = rtnl_dereference(vlan->taps[vlan->numvtaps - 1]);
815f236d
JW
171 nq->queue_index = index;
172
173 rcu_assign_pointer(vlan->taps[index], nq);
174 RCU_INIT_POINTER(vlan->taps[vlan->numvtaps - 1], NULL);
175 q->enabled = false;
176
177 vlan->numvtaps--;
178 }
179
180 return 0;
181}
182
20d29d7a 183/*
02df55d2
AB
184 * The file owning the queue got closed, give up both
185 * the reference that the files holds as well as the
186 * one from the macvlan_dev if that still exists.
20d29d7a
AB
187 *
188 * Using the spinlock makes sure that we don't get
189 * to the queue again after destroying it.
20d29d7a 190 */
02df55d2 191static void macvtap_put_queue(struct macvtap_queue *q)
20d29d7a 192{
02df55d2 193 struct macvlan_dev *vlan;
20d29d7a 194
441ac0fc
VY
195 rtnl_lock();
196 vlan = rtnl_dereference(q->vlan);
197
02df55d2 198 if (vlan) {
815f236d 199 if (q->enabled)
441ac0fc 200 BUG_ON(macvtap_disable_queue(q));
376b1aab 201
815f236d 202 vlan->numqueues--;
2cfa5a04 203 RCU_INIT_POINTER(q->vlan, NULL);
02df55d2 204 sock_put(&q->sk);
815f236d 205 list_del_init(&q->next);
20d29d7a
AB
206 }
207
441ac0fc 208 rtnl_unlock();
20d29d7a
AB
209
210 synchronize_rcu();
211 sock_put(&q->sk);
212}
213
214/*
1565c7c1
KK
215 * Select a queue based on the rxq of the device on which this packet
216 * arrived. If the incoming device is not mq, calculate a flow hash
217 * to select a queue. If all fails, find the first available queue.
218 * Cache vlan->numvtaps since it can become zero during the execution
219 * of this function.
20d29d7a
AB
220 */
221static struct macvtap_queue *macvtap_get_queue(struct net_device *dev,
222 struct sk_buff *skb)
223{
224 struct macvlan_dev *vlan = netdev_priv(dev);
1565c7c1 225 struct macvtap_queue *tap = NULL;
815f236d
JW
226 /* Access to taps array is protected by rcu, but access to numvtaps
227 * isn't. Below we use it to lookup a queue, but treat it as a hint
228 * and validate that the result isn't NULL - in case we are
229 * racing against queue removal.
230 */
ed0483fa 231 int numvtaps = ACCESS_ONCE(vlan->numvtaps);
1565c7c1
KK
232 __u32 rxq;
233
234 if (!numvtaps)
235 goto out;
236
ef0002b5 237 /* Check if we can use flow to select a queue */
3958afa1 238 rxq = skb_get_hash(skb);
ef0002b5
KK
239 if (rxq) {
240 tap = rcu_dereference(vlan->taps[rxq % numvtaps]);
376b1aab 241 goto out;
ef0002b5
KK
242 }
243
1565c7c1
KK
244 if (likely(skb_rx_queue_recorded(skb))) {
245 rxq = skb_get_rx_queue(skb);
20d29d7a 246
1565c7c1
KK
247 while (unlikely(rxq >= numvtaps))
248 rxq -= numvtaps;
249
250 tap = rcu_dereference(vlan->taps[rxq]);
376b1aab 251 goto out;
1565c7c1
KK
252 }
253
376b1aab 254 tap = rcu_dereference(vlan->taps[0]);
1565c7c1
KK
255out:
256 return tap;
20d29d7a
AB
257}
258
02df55d2
AB
259/*
260 * The net_device is going away, give up the reference
1565c7c1
KK
261 * that it holds on all queues and safely set the pointer
262 * from the queues to NULL.
02df55d2 263 */
20d29d7a
AB
264static void macvtap_del_queues(struct net_device *dev)
265{
266 struct macvlan_dev *vlan = netdev_priv(dev);
815f236d 267 struct macvtap_queue *q, *tmp, *qlist[MAX_MACVTAP_QUEUES];
1565c7c1 268 int i, j = 0;
02df55d2 269
441ac0fc 270 ASSERT_RTNL();
815f236d
JW
271 list_for_each_entry_safe(q, tmp, &vlan->queue_list, next) {
272 list_del_init(&q->next);
376b1aab 273 qlist[j++] = q;
376b1aab 274 RCU_INIT_POINTER(q->vlan, NULL);
815f236d
JW
275 if (q->enabled)
276 vlan->numvtaps--;
277 vlan->numqueues--;
564517e8 278 }
815f236d
JW
279 for (i = 0; i < vlan->numvtaps; i++)
280 RCU_INIT_POINTER(vlan->taps[i], NULL);
281 BUG_ON(vlan->numvtaps);
282 BUG_ON(vlan->numqueues);
99f34b38
EB
283 /* guarantee that any future macvtap_set_queue will fail */
284 vlan->numvtaps = MAX_MACVTAP_QUEUES;
1565c7c1
KK
285
286 for (--j; j >= 0; j--)
287 sock_put(&qlist[j]->sk);
20d29d7a
AB
288}
289
6acf54f1 290static rx_handler_result_t macvtap_handle_frame(struct sk_buff **pskb)
20d29d7a 291{
6acf54f1
VY
292 struct sk_buff *skb = *pskb;
293 struct net_device *dev = skb->dev;
294 struct macvlan_dev *vlan;
295 struct macvtap_queue *q;
a567dd62
VY
296 netdev_features_t features = TAP_FEATURES;
297
6acf54f1
VY
298 vlan = macvtap_get_vlan_rcu(dev);
299 if (!vlan)
300 return RX_HANDLER_PASS;
301
302 q = macvtap_get_queue(dev, skb);
20d29d7a 303 if (!q)
6acf54f1 304 return RX_HANDLER_PASS;
8a35747a
HX
305
306 if (skb_queue_len(&q->sk.sk_receive_queue) >= dev->tx_queue_len)
307 goto drop;
20d29d7a 308
6acf54f1
VY
309 skb_push(skb, ETH_HLEN);
310
3e4f8b78 311 /* Apply the forward feature mask so that we perform segmentation
e5733321
VY
312 * according to users wishes. This only works if VNET_HDR is
313 * enabled.
3e4f8b78 314 */
e5733321
VY
315 if (q->flags & IFF_VNET_HDR)
316 features |= vlan->tap_features;
04ffcb25 317 if (netif_needs_gso(dev, skb, features)) {
3e4f8b78
VY
318 struct sk_buff *segs = __skb_gso_segment(skb, features, false);
319
320 if (IS_ERR(segs))
321 goto drop;
322
323 if (!segs) {
324 skb_queue_tail(&q->sk.sk_receive_queue, skb);
325 goto wake_up;
326 }
327
328 kfree_skb(skb);
329 while (segs) {
330 struct sk_buff *nskb = segs->next;
331
332 segs->next = NULL;
333 skb_queue_tail(&q->sk.sk_receive_queue, segs);
334 segs = nskb;
335 }
336 } else {
cbdb0427
VY
337 /* If we receive a partial checksum and the tap side
338 * doesn't support checksum offload, compute the checksum.
339 * Note: it doesn't matter which checksum feature to
340 * check, we either support them all or none.
341 */
342 if (skb->ip_summed == CHECKSUM_PARTIAL &&
343 !(features & NETIF_F_ALL_CSUM) &&
344 skb_checksum_help(skb))
345 goto drop;
3e4f8b78
VY
346 skb_queue_tail(&q->sk.sk_receive_queue, skb);
347 }
348
349wake_up:
4a4771a5 350 wake_up_interruptible_poll(sk_sleep(&q->sk), POLLIN | POLLRDNORM | POLLRDBAND);
6acf54f1 351 return RX_HANDLER_CONSUMED;
8a35747a
HX
352
353drop:
6acf54f1
VY
354 /* Count errors/drops only here, thus don't care about args. */
355 macvlan_count_rx(vlan, 0, 0, 0);
8a35747a 356 kfree_skb(skb);
6acf54f1 357 return RX_HANDLER_CONSUMED;
20d29d7a
AB
358}
359
e09eff7f
EB
360static int macvtap_get_minor(struct macvlan_dev *vlan)
361{
362 int retval = -ENOMEM;
e09eff7f
EB
363
364 mutex_lock(&minor_lock);
ec09ebc1
TH
365 retval = idr_alloc(&minor_idr, vlan, 1, MACVTAP_NUM_DEVS, GFP_KERNEL);
366 if (retval >= 0) {
367 vlan->minor = retval;
368 } else if (retval == -ENOSPC) {
e09eff7f
EB
369 printk(KERN_ERR "too many macvtap devices\n");
370 retval = -EINVAL;
e09eff7f 371 }
e09eff7f 372 mutex_unlock(&minor_lock);
ec09ebc1 373 return retval < 0 ? retval : 0;
e09eff7f
EB
374}
375
376static void macvtap_free_minor(struct macvlan_dev *vlan)
377{
378 mutex_lock(&minor_lock);
379 if (vlan->minor) {
380 idr_remove(&minor_idr, vlan->minor);
381 vlan->minor = 0;
382 }
383 mutex_unlock(&minor_lock);
384}
385
386static struct net_device *dev_get_by_macvtap_minor(int minor)
387{
388 struct net_device *dev = NULL;
389 struct macvlan_dev *vlan;
390
391 mutex_lock(&minor_lock);
392 vlan = idr_find(&minor_idr, minor);
393 if (vlan) {
394 dev = vlan->dev;
395 dev_hold(dev);
396 }
397 mutex_unlock(&minor_lock);
398 return dev;
399}
400
20d29d7a
AB
401static int macvtap_newlink(struct net *src_net,
402 struct net_device *dev,
403 struct nlattr *tb[],
404 struct nlattr *data[])
405{
815f236d 406 struct macvlan_dev *vlan = netdev_priv(dev);
6acf54f1
VY
407 int err;
408
815f236d
JW
409 INIT_LIST_HEAD(&vlan->queue_list);
410
2be5c767
VY
411 /* Since macvlan supports all offloads by default, make
412 * tap support all offloads also.
413 */
414 vlan->tap_features = TUN_OFFLOADS;
415
6acf54f1
VY
416 err = netdev_rx_handler_register(dev, macvtap_handle_frame, vlan);
417 if (err)
418 return err;
419
9bf1907f
EB
420 /* Don't put anything that may fail after macvlan_common_newlink
421 * because we can't undo what it does.
422 */
2f6a1b66 423 return macvlan_common_newlink(src_net, dev, tb, data);
20d29d7a
AB
424}
425
426static void macvtap_dellink(struct net_device *dev,
427 struct list_head *head)
428{
6acf54f1 429 netdev_rx_handler_unregister(dev);
20d29d7a
AB
430 macvtap_del_queues(dev);
431 macvlan_dellink(dev, head);
432}
433
8a35747a
HX
434static void macvtap_setup(struct net_device *dev)
435{
436 macvlan_common_setup(dev);
437 dev->tx_queue_len = TUN_READQ_SIZE;
438}
439
20d29d7a
AB
440static struct rtnl_link_ops macvtap_link_ops __read_mostly = {
441 .kind = "macvtap",
8a35747a 442 .setup = macvtap_setup,
20d29d7a
AB
443 .newlink = macvtap_newlink,
444 .dellink = macvtap_dellink,
445};
446
447
448static void macvtap_sock_write_space(struct sock *sk)
449{
43815482
ED
450 wait_queue_head_t *wqueue;
451
20d29d7a
AB
452 if (!sock_writeable(sk) ||
453 !test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags))
454 return;
455
43815482
ED
456 wqueue = sk_sleep(sk);
457 if (wqueue && waitqueue_active(wqueue))
458 wake_up_interruptible_poll(wqueue, POLLOUT | POLLWRNORM | POLLWRBAND);
20d29d7a
AB
459}
460
2259fef0
EB
461static void macvtap_sock_destruct(struct sock *sk)
462{
463 skb_queue_purge(&sk->sk_receive_queue);
464}
465
20d29d7a
AB
466static int macvtap_open(struct inode *inode, struct file *file)
467{
468 struct net *net = current->nsproxy->net_ns;
40b8fe45 469 struct net_device *dev;
20d29d7a 470 struct macvtap_queue *q;
40b8fe45 471 int err = -ENODEV;
20d29d7a 472
40b8fe45
VY
473 rtnl_lock();
474 dev = dev_get_by_macvtap_minor(iminor(inode));
20d29d7a
AB
475 if (!dev)
476 goto out;
477
20d29d7a
AB
478 err = -ENOMEM;
479 q = (struct macvtap_queue *)sk_alloc(net, AF_UNSPEC, GFP_KERNEL,
480 &macvtap_proto);
481 if (!q)
482 goto out;
483
d9a90a31 484 RCU_INIT_POINTER(q->sock.wq, &q->wq);
43815482 485 init_waitqueue_head(&q->wq.wait);
20d29d7a
AB
486 q->sock.type = SOCK_RAW;
487 q->sock.state = SS_CONNECTED;
501c774c
AB
488 q->sock.file = file;
489 q->sock.ops = &macvtap_socket_ops;
20d29d7a 490 sock_init_data(&q->sock, &q->sk);
20d29d7a 491 q->sk.sk_write_space = macvtap_sock_write_space;
2259fef0 492 q->sk.sk_destruct = macvtap_sock_destruct;
b9fb9ee0 493 q->flags = IFF_VNET_HDR | IFF_NO_PI | IFF_TAP;
55afbd08 494 q->vnet_hdr_sz = sizeof(struct virtio_net_hdr);
20d29d7a 495
97bc3633
SM
496 /*
497 * so far only KVM virtio_net uses macvtap, enable zero copy between
498 * guest kernel and host kernel when lower device supports zerocopy
047af9cf
EB
499 *
500 * The macvlan supports zerocopy iff the lower device supports zero
501 * copy so we don't have to look at the lower device directly.
97bc3633 502 */
047af9cf
EB
503 if ((dev->features & NETIF_F_HIGHDMA) && (dev->features & NETIF_F_SG))
504 sock_set_flag(&q->sk, SOCK_ZEROCOPY);
97bc3633 505
20d29d7a
AB
506 err = macvtap_set_queue(dev, file, q);
507 if (err)
508 sock_put(&q->sk);
509
510out:
511 if (dev)
512 dev_put(dev);
513
40b8fe45 514 rtnl_unlock();
20d29d7a
AB
515 return err;
516}
517
518static int macvtap_release(struct inode *inode, struct file *file)
519{
02df55d2
AB
520 struct macvtap_queue *q = file->private_data;
521 macvtap_put_queue(q);
20d29d7a
AB
522 return 0;
523}
524
525static unsigned int macvtap_poll(struct file *file, poll_table * wait)
526{
02df55d2 527 struct macvtap_queue *q = file->private_data;
20d29d7a
AB
528 unsigned int mask = POLLERR;
529
530 if (!q)
531 goto out;
532
533 mask = 0;
43815482 534 poll_wait(file, &q->wq.wait, wait);
20d29d7a
AB
535
536 if (!skb_queue_empty(&q->sk.sk_receive_queue))
537 mask |= POLLIN | POLLRDNORM;
538
539 if (sock_writeable(&q->sk) ||
540 (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &q->sock.flags) &&
541 sock_writeable(&q->sk)))
542 mask |= POLLOUT | POLLWRNORM;
543
544out:
20d29d7a
AB
545 return mask;
546}
547
b9fb9ee0
AB
548static inline struct sk_buff *macvtap_alloc_skb(struct sock *sk, size_t prepad,
549 size_t len, size_t linear,
550 int noblock, int *err)
551{
552 struct sk_buff *skb;
553
554 /* Under a page? Don't bother with paged skb. */
555 if (prepad + len < PAGE_SIZE || !linear)
556 linear = len;
557
558 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
28d64271 559 err, 0);
b9fb9ee0
AB
560 if (!skb)
561 return NULL;
562
563 skb_reserve(skb, prepad);
564 skb_put(skb, linear);
565 skb->data_len = len - linear;
566 skb->len += len - linear;
567
568 return skb;
569}
570
571/*
572 * macvtap_skb_from_vnet_hdr and macvtap_skb_to_vnet_hdr should
573 * be shared with the tun/tap driver.
574 */
6ae7feb3
MT
575static int macvtap_skb_from_vnet_hdr(struct macvtap_queue *q,
576 struct sk_buff *skb,
b9fb9ee0
AB
577 struct virtio_net_hdr *vnet_hdr)
578{
579 unsigned short gso_type = 0;
580 if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
581 switch (vnet_hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
582 case VIRTIO_NET_HDR_GSO_TCPV4:
583 gso_type = SKB_GSO_TCPV4;
584 break;
585 case VIRTIO_NET_HDR_GSO_TCPV6:
586 gso_type = SKB_GSO_TCPV6;
587 break;
588 case VIRTIO_NET_HDR_GSO_UDP:
3d0ad094
BH
589 pr_warn_once("macvtap: %s: using disabled UFO feature; please fix this program\n",
590 current->comm);
b9fb9ee0 591 gso_type = SKB_GSO_UDP;
5188cd44
BH
592 if (skb->protocol == htons(ETH_P_IPV6))
593 ipv6_proxy_select_ident(skb);
b9fb9ee0
AB
594 break;
595 default:
596 return -EINVAL;
597 }
598
599 if (vnet_hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN)
600 gso_type |= SKB_GSO_TCP_ECN;
601
602 if (vnet_hdr->gso_size == 0)
603 return -EINVAL;
604 }
605
606 if (vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
6ae7feb3
MT
607 if (!skb_partial_csum_set(skb, macvtap16_to_cpu(q, vnet_hdr->csum_start),
608 macvtap16_to_cpu(q, vnet_hdr->csum_offset)))
b9fb9ee0
AB
609 return -EINVAL;
610 }
611
612 if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
6ae7feb3 613 skb_shinfo(skb)->gso_size = macvtap16_to_cpu(q, vnet_hdr->gso_size);
c9af6db4 614 skb_shinfo(skb)->gso_type = gso_type;
b9fb9ee0
AB
615
616 /* Header must be checked, and gso_segs computed. */
617 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
618 skb_shinfo(skb)->gso_segs = 0;
619 }
620 return 0;
621}
622
6ae7feb3
MT
623static void macvtap_skb_to_vnet_hdr(struct macvtap_queue *q,
624 const struct sk_buff *skb,
625 struct virtio_net_hdr *vnet_hdr)
b9fb9ee0
AB
626{
627 memset(vnet_hdr, 0, sizeof(*vnet_hdr));
628
629 if (skb_is_gso(skb)) {
630 struct skb_shared_info *sinfo = skb_shinfo(skb);
631
632 /* This is a hint as to how much should be linear. */
6ae7feb3
MT
633 vnet_hdr->hdr_len = cpu_to_macvtap16(q, skb_headlen(skb));
634 vnet_hdr->gso_size = cpu_to_macvtap16(q, sinfo->gso_size);
b9fb9ee0
AB
635 if (sinfo->gso_type & SKB_GSO_TCPV4)
636 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
637 else if (sinfo->gso_type & SKB_GSO_TCPV6)
638 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
b9fb9ee0
AB
639 else
640 BUG();
641 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
642 vnet_hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
643 } else
644 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
645
646 if (skb->ip_summed == CHECKSUM_PARTIAL) {
647 vnet_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
3ce9b20f 648 if (vlan_tx_tag_present(skb))
6ae7feb3
MT
649 vnet_hdr->csum_start = cpu_to_macvtap16(q,
650 skb_checksum_start_offset(skb) + VLAN_HLEN);
651 else
652 vnet_hdr->csum_start = cpu_to_macvtap16(q,
653 skb_checksum_start_offset(skb));
654 vnet_hdr->csum_offset = cpu_to_macvtap16(q, skb->csum_offset);
10a8d94a
JW
655 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
656 vnet_hdr->flags = VIRTIO_NET_HDR_F_DATA_VALID;
b9fb9ee0 657 } /* else everything is zero */
b9fb9ee0
AB
658}
659
20d29d7a 660/* Get packet from user space buffer */
97bc3633 661static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
f5ff53b4 662 struct iov_iter *from, int noblock)
20d29d7a 663{
16a3fa28 664 int good_linear = SKB_MAX_HEAD(NET_IP_ALIGN);
20d29d7a 665 struct sk_buff *skb;
02df55d2 666 struct macvlan_dev *vlan;
f5ff53b4 667 unsigned long total_len = iov_iter_count(from);
97bc3633 668 unsigned long len = total_len;
20d29d7a 669 int err;
b9fb9ee0
AB
670 struct virtio_net_hdr vnet_hdr = { 0 };
671 int vnet_hdr_len = 0;
b92946e2 672 int copylen = 0;
97bc3633 673 bool zerocopy = false;
61d46bf9 674 size_t linear;
f5ff53b4 675 ssize_t n;
b9fb9ee0
AB
676
677 if (q->flags & IFF_VNET_HDR) {
55afbd08 678 vnet_hdr_len = q->vnet_hdr_sz;
b9fb9ee0
AB
679
680 err = -EINVAL;
ce3c8692 681 if (len < vnet_hdr_len)
b9fb9ee0 682 goto err;
ce3c8692 683 len -= vnet_hdr_len;
b9fb9ee0 684
f5ff53b4
AV
685 err = -EFAULT;
686 n = copy_from_iter(&vnet_hdr, sizeof(vnet_hdr), from);
687 if (n != sizeof(vnet_hdr))
b9fb9ee0 688 goto err;
f5ff53b4 689 iov_iter_advance(from, vnet_hdr_len - sizeof(vnet_hdr));
b9fb9ee0 690 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
6ae7feb3
MT
691 macvtap16_to_cpu(q, vnet_hdr.csum_start) +
692 macvtap16_to_cpu(q, vnet_hdr.csum_offset) + 2 >
693 macvtap16_to_cpu(q, vnet_hdr.hdr_len))
694 vnet_hdr.hdr_len = cpu_to_macvtap16(q,
695 macvtap16_to_cpu(q, vnet_hdr.csum_start) +
696 macvtap16_to_cpu(q, vnet_hdr.csum_offset) + 2);
b9fb9ee0 697 err = -EINVAL;
6ae7feb3 698 if (macvtap16_to_cpu(q, vnet_hdr.hdr_len) > len)
b9fb9ee0
AB
699 goto err;
700 }
20d29d7a 701
b9fb9ee0 702 err = -EINVAL;
20d29d7a 703 if (unlikely(len < ETH_HLEN))
b9fb9ee0 704 goto err;
20d29d7a 705
ece793fc 706 if (m && m->msg_control && sock_flag(&q->sk, SOCK_ZEROCOPY)) {
f5ff53b4
AV
707 struct iov_iter i;
708
6ae7feb3
MT
709 copylen = vnet_hdr.hdr_len ?
710 macvtap16_to_cpu(q, vnet_hdr.hdr_len) : GOODCOPY_LEN;
16a3fa28
JW
711 if (copylen > good_linear)
712 copylen = good_linear;
61d46bf9 713 linear = copylen;
f5ff53b4
AV
714 i = *from;
715 iov_iter_advance(&i, copylen);
716 if (iov_iter_npages(&i, INT_MAX) <= MAX_SKB_FRAGS)
ece793fc
JW
717 zerocopy = true;
718 }
719
720 if (!zerocopy) {
97bc3633 721 copylen = len;
6ae7feb3 722 if (macvtap16_to_cpu(q, vnet_hdr.hdr_len) > good_linear)
16a3fa28
JW
723 linear = good_linear;
724 else
6ae7feb3 725 linear = macvtap16_to_cpu(q, vnet_hdr.hdr_len);
61d46bf9 726 }
97bc3633
SM
727
728 skb = macvtap_alloc_skb(&q->sk, NET_IP_ALIGN, copylen,
61d46bf9 729 linear, noblock, &err);
02df55d2
AB
730 if (!skb)
731 goto err;
20d29d7a 732
01d6657b 733 if (zerocopy)
f5ff53b4 734 err = zerocopy_sg_from_iter(skb, from);
ece793fc 735 else {
f5ff53b4 736 err = skb_copy_datagram_from_iter(skb, 0, from, len);
ece793fc
JW
737 if (!err && m && m->msg_control) {
738 struct ubuf_info *uarg = m->msg_control;
739 uarg->callback(uarg, false);
740 }
741 }
742
02df55d2 743 if (err)
b9fb9ee0 744 goto err_kfree;
20d29d7a
AB
745
746 skb_set_network_header(skb, ETH_HLEN);
b9fb9ee0
AB
747 skb_reset_mac_header(skb);
748 skb->protocol = eth_hdr(skb)->h_proto;
749
750 if (vnet_hdr_len) {
6ae7feb3 751 err = macvtap_skb_from_vnet_hdr(q, skb, &vnet_hdr);
b9fb9ee0
AB
752 if (err)
753 goto err_kfree;
754 }
755
40893fd0 756 skb_probe_transport_header(skb, ETH_HLEN);
9b4d669b 757
ac4e4af1
VY
758 rcu_read_lock();
759 vlan = rcu_dereference(q->vlan);
97bc3633 760 /* copy skb_ubuf_info for callback when skb has no error */
01d6657b 761 if (zerocopy) {
97bc3633 762 skb_shinfo(skb)->destructor_arg = m->msg_control;
01d6657b 763 skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY;
c9af6db4 764 skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG;
01d6657b 765 }
29d79196 766 if (vlan) {
6acf54f1
VY
767 skb->dev = vlan->dev;
768 dev_queue_xmit(skb);
29d79196 769 } else {
02df55d2 770 kfree_skb(skb);
29d79196 771 }
ac4e4af1 772 rcu_read_unlock();
20d29d7a 773
97bc3633 774 return total_len;
02df55d2 775
b9fb9ee0
AB
776err_kfree:
777 kfree_skb(skb);
778
02df55d2 779err:
ac4e4af1
VY
780 rcu_read_lock();
781 vlan = rcu_dereference(q->vlan);
02df55d2 782 if (vlan)
cd3e22b7 783 this_cpu_inc(vlan->pcpu_stats->tx_dropped);
ac4e4af1 784 rcu_read_unlock();
02df55d2 785
02df55d2 786 return err;
20d29d7a
AB
787}
788
f5ff53b4 789static ssize_t macvtap_write_iter(struct kiocb *iocb, struct iov_iter *from)
20d29d7a
AB
790{
791 struct file *file = iocb->ki_filp;
02df55d2 792 struct macvtap_queue *q = file->private_data;
20d29d7a 793
f5ff53b4 794 return macvtap_get_user(q, NULL, from, file->f_flags & O_NONBLOCK);
20d29d7a
AB
795}
796
797/* Put packet to the user space buffer */
798static ssize_t macvtap_put_user(struct macvtap_queue *q,
799 const struct sk_buff *skb,
6c36d2e2 800 struct iov_iter *iter)
20d29d7a 801{
20d29d7a 802 int ret;
b9fb9ee0 803 int vnet_hdr_len = 0;
f09e2249 804 int vlan_offset = 0;
6c36d2e2 805 int total;
b9fb9ee0
AB
806
807 if (q->flags & IFF_VNET_HDR) {
808 struct virtio_net_hdr vnet_hdr;
55afbd08 809 vnet_hdr_len = q->vnet_hdr_sz;
6c36d2e2 810 if (iov_iter_count(iter) < vnet_hdr_len)
b9fb9ee0
AB
811 return -EINVAL;
812
6ae7feb3 813 macvtap_skb_to_vnet_hdr(q, skb, &vnet_hdr);
b9fb9ee0 814
6c36d2e2
HX
815 if (copy_to_iter(&vnet_hdr, sizeof(vnet_hdr), iter) !=
816 sizeof(vnet_hdr))
b9fb9ee0 817 return -EFAULT;
7cc76f51
JW
818
819 iov_iter_advance(iter, vnet_hdr_len - sizeof(vnet_hdr));
b9fb9ee0 820 }
6c36d2e2 821 total = vnet_hdr_len;
ce232ce0 822 total += skb->len;
f09e2249 823
6c36d2e2 824 if (vlan_tx_tag_present(skb)) {
f09e2249
BG
825 struct {
826 __be16 h_vlan_proto;
827 __be16 h_vlan_TCI;
828 } veth;
0fbe0d47 829 veth.h_vlan_proto = skb->vlan_proto;
f09e2249
BG
830 veth.h_vlan_TCI = htons(vlan_tx_tag_get(skb));
831
832 vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto);
ce232ce0 833 total += VLAN_HLEN;
f09e2249 834
6c36d2e2
HX
835 ret = skb_copy_datagram_iter(skb, 0, iter, vlan_offset);
836 if (ret || !iov_iter_count(iter))
f09e2249
BG
837 goto done;
838
6c36d2e2
HX
839 ret = copy_to_iter(&veth, sizeof(veth), iter);
840 if (ret != sizeof(veth) || !iov_iter_count(iter))
f09e2249
BG
841 goto done;
842 }
20d29d7a 843
6c36d2e2
HX
844 ret = skb_copy_datagram_iter(skb, vlan_offset, iter,
845 skb->len - vlan_offset);
20d29d7a 846
f09e2249 847done:
ce232ce0 848 return ret ? ret : total;
20d29d7a
AB
849}
850
55ec8e25 851static ssize_t macvtap_do_read(struct macvtap_queue *q,
3af0bfe5 852 struct iov_iter *to,
501c774c 853 int noblock)
20d29d7a 854{
ccf7e72b 855 DEFINE_WAIT(wait);
20d29d7a 856 struct sk_buff *skb;
501c774c 857 ssize_t ret = 0;
20d29d7a 858
3af0bfe5
AV
859 if (!iov_iter_count(to))
860 return 0;
861
862 while (1) {
89cee917
JW
863 if (!noblock)
864 prepare_to_wait(sk_sleep(&q->sk), &wait,
865 TASK_INTERRUPTIBLE);
20d29d7a
AB
866
867 /* Read frames from the queue */
868 skb = skb_dequeue(&q->sk.sk_receive_queue);
3af0bfe5
AV
869 if (skb)
870 break;
871 if (noblock) {
872 ret = -EAGAIN;
873 break;
20d29d7a 874 }
3af0bfe5
AV
875 if (signal_pending(current)) {
876 ret = -ERESTARTSYS;
877 break;
878 }
879 /* Nothing to read, let's sleep */
880 schedule();
881 }
882 if (skb) {
883 ret = macvtap_put_user(q, skb, to);
f51a5e82
JW
884 if (unlikely(ret < 0))
885 kfree_skb(skb);
886 else
887 consume_skb(skb);
20d29d7a 888 }
89cee917
JW
889 if (!noblock)
890 finish_wait(sk_sleep(&q->sk), &wait);
501c774c
AB
891 return ret;
892}
893
3af0bfe5 894static ssize_t macvtap_read_iter(struct kiocb *iocb, struct iov_iter *to)
501c774c
AB
895{
896 struct file *file = iocb->ki_filp;
897 struct macvtap_queue *q = file->private_data;
3af0bfe5 898 ssize_t len = iov_iter_count(to), ret;
20d29d7a 899
3af0bfe5 900 ret = macvtap_do_read(q, to, file->f_flags & O_NONBLOCK);
ce232ce0 901 ret = min_t(ssize_t, ret, len);
e6ebc7f1
ZYW
902 if (ret > 0)
903 iocb->ki_pos = ret;
20d29d7a
AB
904 return ret;
905}
906
8f475a31
JW
907static struct macvlan_dev *macvtap_get_vlan(struct macvtap_queue *q)
908{
909 struct macvlan_dev *vlan;
910
441ac0fc
VY
911 ASSERT_RTNL();
912 vlan = rtnl_dereference(q->vlan);
8f475a31
JW
913 if (vlan)
914 dev_hold(vlan->dev);
8f475a31
JW
915
916 return vlan;
917}
918
919static void macvtap_put_vlan(struct macvlan_dev *vlan)
920{
921 dev_put(vlan->dev);
922}
923
815f236d
JW
924static int macvtap_ioctl_set_queue(struct file *file, unsigned int flags)
925{
926 struct macvtap_queue *q = file->private_data;
927 struct macvlan_dev *vlan;
928 int ret;
929
930 vlan = macvtap_get_vlan(q);
931 if (!vlan)
932 return -EINVAL;
933
934 if (flags & IFF_ATTACH_QUEUE)
935 ret = macvtap_enable_queue(vlan->dev, file, q);
936 else if (flags & IFF_DETACH_QUEUE)
937 ret = macvtap_disable_queue(q);
f57855a5
JW
938 else
939 ret = -EINVAL;
815f236d
JW
940
941 macvtap_put_vlan(vlan);
942 return ret;
943}
944
2be5c767
VY
945static int set_offload(struct macvtap_queue *q, unsigned long arg)
946{
947 struct macvlan_dev *vlan;
948 netdev_features_t features;
949 netdev_features_t feature_mask = 0;
950
951 vlan = rtnl_dereference(q->vlan);
952 if (!vlan)
953 return -ENOLINK;
954
955 features = vlan->dev->features;
956
957 if (arg & TUN_F_CSUM) {
958 feature_mask = NETIF_F_HW_CSUM;
959
960 if (arg & (TUN_F_TSO4 | TUN_F_TSO6)) {
961 if (arg & TUN_F_TSO_ECN)
962 feature_mask |= NETIF_F_TSO_ECN;
963 if (arg & TUN_F_TSO4)
964 feature_mask |= NETIF_F_TSO;
965 if (arg & TUN_F_TSO6)
966 feature_mask |= NETIF_F_TSO6;
967 }
2be5c767
VY
968 }
969
970 /* tun/tap driver inverts the usage for TSO offloads, where
971 * setting the TSO bit means that the userspace wants to
972 * accept TSO frames and turning it off means that user space
973 * does not support TSO.
974 * For macvtap, we have to invert it to mean the same thing.
975 * When user space turns off TSO, we turn off GSO/LRO so that
976 * user-space will not receive TSO frames.
977 */
3d0ad094 978 if (feature_mask & (NETIF_F_TSO | NETIF_F_TSO6))
2be5c767
VY
979 features |= RX_OFFLOADS;
980 else
981 features &= ~RX_OFFLOADS;
982
983 /* tap_features are the same as features on tun/tap and
984 * reflect user expectations.
985 */
a567dd62 986 vlan->tap_features = feature_mask;
2be5c767
VY
987 vlan->set_features = features;
988 netdev_update_features(vlan->dev);
989
990 return 0;
991}
992
20d29d7a
AB
993/*
994 * provide compatibility with generic tun/tap interface
995 */
996static long macvtap_ioctl(struct file *file, unsigned int cmd,
997 unsigned long arg)
998{
02df55d2
AB
999 struct macvtap_queue *q = file->private_data;
1000 struct macvlan_dev *vlan;
20d29d7a
AB
1001 void __user *argp = (void __user *)arg;
1002 struct ifreq __user *ifr = argp;
1003 unsigned int __user *up = argp;
39ec7de7 1004 unsigned short u;
55afbd08
MT
1005 int __user *sp = argp;
1006 int s;
02df55d2 1007 int ret;
20d29d7a
AB
1008
1009 switch (cmd) {
1010 case TUNSETIFF:
1011 /* ignore the name, just look at flags */
1012 if (get_user(u, &ifr->ifr_flags))
1013 return -EFAULT;
b9fb9ee0
AB
1014
1015 ret = 0;
6ae7feb3 1016 if ((u & ~MACVTAP_FEATURES) != (IFF_NO_PI | IFF_TAP))
b9fb9ee0
AB
1017 ret = -EINVAL;
1018 else
39ec7de7 1019 q->flags = (q->flags & ~MACVTAP_FEATURES) | u;
b9fb9ee0
AB
1020
1021 return ret;
20d29d7a
AB
1022
1023 case TUNGETIFF:
441ac0fc 1024 rtnl_lock();
8f475a31 1025 vlan = macvtap_get_vlan(q);
441ac0fc
VY
1026 if (!vlan) {
1027 rtnl_unlock();
20d29d7a 1028 return -ENOLINK;
441ac0fc 1029 }
20d29d7a 1030
02df55d2 1031 ret = 0;
39ec7de7 1032 u = q->flags;
13707f9e 1033 if (copy_to_user(&ifr->ifr_name, vlan->dev->name, IFNAMSIZ) ||
39ec7de7 1034 put_user(u, &ifr->ifr_flags))
02df55d2 1035 ret = -EFAULT;
8f475a31 1036 macvtap_put_vlan(vlan);
441ac0fc 1037 rtnl_unlock();
02df55d2 1038 return ret;
20d29d7a 1039
815f236d
JW
1040 case TUNSETQUEUE:
1041 if (get_user(u, &ifr->ifr_flags))
1042 return -EFAULT;
441ac0fc
VY
1043 rtnl_lock();
1044 ret = macvtap_ioctl_set_queue(file, u);
1045 rtnl_unlock();
82a19eb8 1046 return ret;
815f236d 1047
20d29d7a 1048 case TUNGETFEATURES:
6ae7feb3 1049 if (put_user(IFF_TAP | IFF_NO_PI | MACVTAP_FEATURES, up))
20d29d7a
AB
1050 return -EFAULT;
1051 return 0;
1052
1053 case TUNSETSNDBUF:
1054 if (get_user(u, up))
1055 return -EFAULT;
1056
20d29d7a 1057 q->sk.sk_sndbuf = u;
20d29d7a
AB
1058 return 0;
1059
55afbd08
MT
1060 case TUNGETVNETHDRSZ:
1061 s = q->vnet_hdr_sz;
1062 if (put_user(s, sp))
1063 return -EFAULT;
1064 return 0;
1065
1066 case TUNSETVNETHDRSZ:
1067 if (get_user(s, sp))
1068 return -EFAULT;
1069 if (s < (int)sizeof(struct virtio_net_hdr))
1070 return -EINVAL;
1071
1072 q->vnet_hdr_sz = s;
1073 return 0;
1074
01b07fb3
MT
1075 case TUNGETVNETLE:
1076 s = !!(q->flags & MACVTAP_VNET_LE);
1077 if (put_user(s, sp))
1078 return -EFAULT;
1079 return 0;
1080
1081 case TUNSETVNETLE:
1082 if (get_user(s, sp))
1083 return -EFAULT;
1084 if (s)
1085 q->flags |= MACVTAP_VNET_LE;
1086 else
1087 q->flags &= ~MACVTAP_VNET_LE;
1088 return 0;
1089
20d29d7a
AB
1090 case TUNSETOFFLOAD:
1091 /* let the user check for future flags */
1092 if (arg & ~(TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6 |
3d0ad094 1093 TUN_F_TSO_ECN))
20d29d7a
AB
1094 return -EINVAL;
1095
2be5c767
VY
1096 rtnl_lock();
1097 ret = set_offload(q, arg);
1098 rtnl_unlock();
1099 return ret;
20d29d7a
AB
1100
1101 default:
1102 return -EINVAL;
1103 }
1104}
1105
1106#ifdef CONFIG_COMPAT
1107static long macvtap_compat_ioctl(struct file *file, unsigned int cmd,
1108 unsigned long arg)
1109{
1110 return macvtap_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
1111}
1112#endif
1113
1114static const struct file_operations macvtap_fops = {
1115 .owner = THIS_MODULE,
1116 .open = macvtap_open,
1117 .release = macvtap_release,
3af0bfe5 1118 .read = new_sync_read,
f5ff53b4 1119 .write = new_sync_write,
3af0bfe5 1120 .read_iter = macvtap_read_iter,
f5ff53b4 1121 .write_iter = macvtap_write_iter,
20d29d7a
AB
1122 .poll = macvtap_poll,
1123 .llseek = no_llseek,
1124 .unlocked_ioctl = macvtap_ioctl,
1125#ifdef CONFIG_COMPAT
1126 .compat_ioctl = macvtap_compat_ioctl,
1127#endif
1128};
1129
501c774c
AB
1130static int macvtap_sendmsg(struct kiocb *iocb, struct socket *sock,
1131 struct msghdr *m, size_t total_len)
1132{
1133 struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock);
c0371da6 1134 return macvtap_get_user(q, m, &m->msg_iter, m->msg_flags & MSG_DONTWAIT);
501c774c
AB
1135}
1136
1137static int macvtap_recvmsg(struct kiocb *iocb, struct socket *sock,
1138 struct msghdr *m, size_t total_len,
1139 int flags)
1140{
1141 struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock);
1142 int ret;
1143 if (flags & ~(MSG_DONTWAIT|MSG_TRUNC))
1144 return -EINVAL;
c0371da6 1145 ret = macvtap_do_read(q, &m->msg_iter, flags & MSG_DONTWAIT);
de2aa476
DM
1146 if (ret > total_len) {
1147 m->msg_flags |= MSG_TRUNC;
1148 ret = flags & MSG_TRUNC ? ret : total_len;
1149 }
501c774c
AB
1150 return ret;
1151}
1152
1153/* Ops structure to mimic raw sockets with tun */
1154static const struct proto_ops macvtap_socket_ops = {
1155 .sendmsg = macvtap_sendmsg,
1156 .recvmsg = macvtap_recvmsg,
1157};
1158
1159/* Get an underlying socket object from tun file. Returns error unless file is
1160 * attached to a device. The returned object works like a packet socket, it
1161 * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for
1162 * holding a reference to the file for as long as the socket is in use. */
1163struct socket *macvtap_get_socket(struct file *file)
1164{
1165 struct macvtap_queue *q;
1166 if (file->f_op != &macvtap_fops)
1167 return ERR_PTR(-EINVAL);
1168 q = file->private_data;
1169 if (!q)
1170 return ERR_PTR(-EBADFD);
1171 return &q->sock;
1172}
1173EXPORT_SYMBOL_GPL(macvtap_get_socket);
1174
9bf1907f
EB
1175static int macvtap_device_event(struct notifier_block *unused,
1176 unsigned long event, void *ptr)
1177{
351638e7 1178 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
e09eff7f 1179 struct macvlan_dev *vlan;
9bf1907f
EB
1180 struct device *classdev;
1181 dev_t devt;
e09eff7f 1182 int err;
9bf1907f
EB
1183
1184 if (dev->rtnl_link_ops != &macvtap_link_ops)
1185 return NOTIFY_DONE;
1186
e09eff7f 1187 vlan = netdev_priv(dev);
9bf1907f
EB
1188
1189 switch (event) {
1190 case NETDEV_REGISTER:
1191 /* Create the device node here after the network device has
1192 * been registered but before register_netdevice has
1193 * finished running.
1194 */
e09eff7f
EB
1195 err = macvtap_get_minor(vlan);
1196 if (err)
1197 return notifier_from_errno(err);
1198
1199 devt = MKDEV(MAJOR(macvtap_major), vlan->minor);
9bf1907f
EB
1200 classdev = device_create(macvtap_class, &dev->dev, devt,
1201 dev, "tap%d", dev->ifindex);
e09eff7f
EB
1202 if (IS_ERR(classdev)) {
1203 macvtap_free_minor(vlan);
9bf1907f 1204 return notifier_from_errno(PTR_ERR(classdev));
e09eff7f 1205 }
9bf1907f
EB
1206 break;
1207 case NETDEV_UNREGISTER:
e09eff7f 1208 devt = MKDEV(MAJOR(macvtap_major), vlan->minor);
9bf1907f 1209 device_destroy(macvtap_class, devt);
e09eff7f 1210 macvtap_free_minor(vlan);
9bf1907f
EB
1211 break;
1212 }
1213
1214 return NOTIFY_DONE;
1215}
1216
1217static struct notifier_block macvtap_notifier_block __read_mostly = {
1218 .notifier_call = macvtap_device_event,
1219};
1220
20d29d7a
AB
1221static int macvtap_init(void)
1222{
1223 int err;
1224
1225 err = alloc_chrdev_region(&macvtap_major, 0,
1226 MACVTAP_NUM_DEVS, "macvtap");
1227 if (err)
1228 goto out1;
1229
1230 cdev_init(&macvtap_cdev, &macvtap_fops);
1231 err = cdev_add(&macvtap_cdev, macvtap_major, MACVTAP_NUM_DEVS);
1232 if (err)
1233 goto out2;
1234
1235 macvtap_class = class_create(THIS_MODULE, "macvtap");
1236 if (IS_ERR(macvtap_class)) {
1237 err = PTR_ERR(macvtap_class);
1238 goto out3;
1239 }
1240
9bf1907f 1241 err = register_netdevice_notifier(&macvtap_notifier_block);
20d29d7a
AB
1242 if (err)
1243 goto out4;
1244
9bf1907f
EB
1245 err = macvlan_link_register(&macvtap_link_ops);
1246 if (err)
1247 goto out5;
1248
20d29d7a
AB
1249 return 0;
1250
9bf1907f
EB
1251out5:
1252 unregister_netdevice_notifier(&macvtap_notifier_block);
20d29d7a
AB
1253out4:
1254 class_unregister(macvtap_class);
1255out3:
1256 cdev_del(&macvtap_cdev);
1257out2:
1258 unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
1259out1:
1260 return err;
1261}
1262module_init(macvtap_init);
1263
1264static void macvtap_exit(void)
1265{
1266 rtnl_link_unregister(&macvtap_link_ops);
9bf1907f 1267 unregister_netdevice_notifier(&macvtap_notifier_block);
20d29d7a
AB
1268 class_unregister(macvtap_class);
1269 cdev_del(&macvtap_cdev);
1270 unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
1271}
1272module_exit(macvtap_exit);
1273
1274MODULE_ALIAS_RTNL_LINK("macvtap");
1275MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
1276MODULE_LICENSE("GPL");