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