Commit | Line | Data |
---|---|---|
20d29d7a AB |
1 | #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> | |
5a0e3ad6 | 12 | #include <linux/slab.h> |
20d29d7a AB |
13 | #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> | |
b9fb9ee0 | 21 | #include <linux/virtio_net.h> |
20d29d7a AB |
22 | |
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 | */ | |
37 | struct macvtap_queue { | |
38 | struct sock sk; | |
39 | struct socket sock; | |
43815482 | 40 | struct socket_wq wq; |
55afbd08 | 41 | int vnet_hdr_sz; |
20d29d7a AB |
42 | struct macvlan_dev *vlan; |
43 | struct file *file; | |
b9fb9ee0 | 44 | unsigned int flags; |
20d29d7a AB |
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 | * Minor number matches netdev->ifindex, so need a potentially | |
55 | * large value. This also makes it possible to split the | |
56 | * tap functionality out again in the future by offering it | |
57 | * from other drivers besides macvtap. As long as every device | |
58 | * only has one tap, the interface numbers assure that the | |
59 | * device nodes are unique. | |
60 | */ | |
1ebed71a | 61 | static dev_t macvtap_major; |
20d29d7a AB |
62 | #define MACVTAP_NUM_DEVS 65536 |
63 | static struct class *macvtap_class; | |
64 | static struct cdev macvtap_cdev; | |
65 | ||
501c774c AB |
66 | static const struct proto_ops macvtap_socket_ops; |
67 | ||
20d29d7a AB |
68 | /* |
69 | * RCU usage: | |
02df55d2 AB |
70 | * The macvtap_queue and the macvlan_dev are loosely coupled, the |
71 | * pointers from one to the other can only be read while rcu_read_lock | |
72 | * or macvtap_lock is held. | |
20d29d7a | 73 | * |
02df55d2 AB |
74 | * Both the file and the macvlan_dev hold a reference on the macvtap_queue |
75 | * through sock_hold(&q->sk). When the macvlan_dev goes away first, | |
76 | * q->vlan becomes inaccessible. When the files gets closed, | |
77 | * macvtap_get_queue() fails. | |
20d29d7a | 78 | * |
02df55d2 AB |
79 | * There may still be references to the struct sock inside of the |
80 | * queue from outbound SKBs, but these never reference back to the | |
81 | * file or the dev. The data structure is freed through __sk_free | |
82 | * when both our references and any pending SKBs are gone. | |
20d29d7a AB |
83 | */ |
84 | static DEFINE_SPINLOCK(macvtap_lock); | |
85 | ||
86 | /* | |
1565c7c1 KK |
87 | * get_slot: return a [unused/occupied] slot in vlan->taps[]: |
88 | * - if 'q' is NULL, return the first empty slot; | |
89 | * - otherwise, return the slot this pointer occupies. | |
20d29d7a | 90 | */ |
1565c7c1 KK |
91 | static int get_slot(struct macvlan_dev *vlan, struct macvtap_queue *q) |
92 | { | |
93 | int i; | |
94 | ||
95 | for (i = 0; i < MAX_MACVTAP_QUEUES; i++) { | |
96 | if (rcu_dereference(vlan->taps[i]) == q) | |
97 | return i; | |
98 | } | |
99 | ||
100 | /* Should never happen */ | |
101 | BUG_ON(1); | |
102 | } | |
103 | ||
20d29d7a AB |
104 | static int macvtap_set_queue(struct net_device *dev, struct file *file, |
105 | struct macvtap_queue *q) | |
106 | { | |
107 | struct macvlan_dev *vlan = netdev_priv(dev); | |
1565c7c1 | 108 | int index; |
20d29d7a AB |
109 | int err = -EBUSY; |
110 | ||
111 | spin_lock(&macvtap_lock); | |
1565c7c1 | 112 | if (vlan->numvtaps == MAX_MACVTAP_QUEUES) |
20d29d7a AB |
113 | goto out; |
114 | ||
115 | err = 0; | |
1565c7c1 | 116 | index = get_slot(vlan, NULL); |
02df55d2 | 117 | rcu_assign_pointer(q->vlan, vlan); |
1565c7c1 | 118 | rcu_assign_pointer(vlan->taps[index], q); |
02df55d2 | 119 | sock_hold(&q->sk); |
20d29d7a AB |
120 | |
121 | q->file = file; | |
02df55d2 | 122 | file->private_data = q; |
20d29d7a | 123 | |
1565c7c1 KK |
124 | vlan->numvtaps++; |
125 | ||
20d29d7a AB |
126 | out: |
127 | spin_unlock(&macvtap_lock); | |
128 | return err; | |
129 | } | |
130 | ||
131 | /* | |
02df55d2 AB |
132 | * The file owning the queue got closed, give up both |
133 | * the reference that the files holds as well as the | |
134 | * one from the macvlan_dev if that still exists. | |
20d29d7a AB |
135 | * |
136 | * Using the spinlock makes sure that we don't get | |
137 | * to the queue again after destroying it. | |
20d29d7a | 138 | */ |
02df55d2 | 139 | static void macvtap_put_queue(struct macvtap_queue *q) |
20d29d7a | 140 | { |
02df55d2 | 141 | struct macvlan_dev *vlan; |
20d29d7a AB |
142 | |
143 | spin_lock(&macvtap_lock); | |
02df55d2 AB |
144 | vlan = rcu_dereference(q->vlan); |
145 | if (vlan) { | |
1565c7c1 KK |
146 | int index = get_slot(vlan, q); |
147 | ||
148 | rcu_assign_pointer(vlan->taps[index], NULL); | |
02df55d2 AB |
149 | rcu_assign_pointer(q->vlan, NULL); |
150 | sock_put(&q->sk); | |
1565c7c1 | 151 | --vlan->numvtaps; |
20d29d7a AB |
152 | } |
153 | ||
20d29d7a AB |
154 | spin_unlock(&macvtap_lock); |
155 | ||
156 | synchronize_rcu(); | |
157 | sock_put(&q->sk); | |
158 | } | |
159 | ||
160 | /* | |
1565c7c1 KK |
161 | * 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. | |
20d29d7a AB |
166 | */ |
167 | static struct macvtap_queue *macvtap_get_queue(struct net_device *dev, | |
168 | struct sk_buff *skb) | |
169 | { | |
170 | struct macvlan_dev *vlan = netdev_priv(dev); | |
1565c7c1 KK |
171 | struct macvtap_queue *tap = NULL; |
172 | int numvtaps = vlan->numvtaps; | |
173 | __u32 rxq; | |
174 | ||
175 | if (!numvtaps) | |
176 | goto out; | |
177 | ||
178 | if (likely(skb_rx_queue_recorded(skb))) { | |
179 | rxq = skb_get_rx_queue(skb); | |
20d29d7a | 180 | |
1565c7c1 KK |
181 | while (unlikely(rxq >= numvtaps)) |
182 | rxq -= numvtaps; | |
183 | ||
184 | tap = rcu_dereference(vlan->taps[rxq]); | |
185 | if (tap) | |
186 | goto out; | |
187 | } | |
188 | ||
189 | /* Check if we can use flow to select a queue */ | |
190 | rxq = skb_get_rxhash(skb); | |
191 | if (rxq) { | |
192 | tap = rcu_dereference(vlan->taps[rxq % numvtaps]); | |
193 | if (tap) | |
194 | goto out; | |
195 | } | |
196 | ||
197 | /* 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 | ||
204 | out: | |
205 | return tap; | |
20d29d7a AB |
206 | } |
207 | ||
02df55d2 AB |
208 | /* |
209 | * The net_device is going away, give up the reference | |
1565c7c1 KK |
210 | * that it holds on all queues and safely set the pointer |
211 | * from the queues to NULL. | |
02df55d2 | 212 | */ |
20d29d7a AB |
213 | static void macvtap_del_queues(struct net_device *dev) |
214 | { | |
215 | struct macvlan_dev *vlan = netdev_priv(dev); | |
1565c7c1 KK |
216 | struct macvtap_queue *q, *qlist[MAX_MACVTAP_QUEUES]; |
217 | int i, j = 0; | |
02df55d2 | 218 | |
1565c7c1 | 219 | /* macvtap_put_queue can free some slots, so go through all slots */ |
02df55d2 | 220 | spin_lock(&macvtap_lock); |
1565c7c1 KK |
221 | for (i = 0; i < MAX_MACVTAP_QUEUES && vlan->numvtaps; i++) { |
222 | q = rcu_dereference(vlan->taps[i]); | |
223 | if (q) { | |
224 | qlist[j++] = q; | |
225 | rcu_assign_pointer(vlan->taps[i], NULL); | |
226 | rcu_assign_pointer(q->vlan, NULL); | |
227 | vlan->numvtaps--; | |
228 | } | |
564517e8 | 229 | } |
1565c7c1 | 230 | BUG_ON(vlan->numvtaps != 0); |
02df55d2 AB |
231 | spin_unlock(&macvtap_lock); |
232 | ||
233 | synchronize_rcu(); | |
1565c7c1 KK |
234 | |
235 | for (--j; j >= 0; j--) | |
236 | sock_put(&qlist[j]->sk); | |
20d29d7a AB |
237 | } |
238 | ||
239 | /* | |
240 | * Forward happens for data that gets sent from one macvlan | |
241 | * endpoint to another one in bridge mode. We just take | |
242 | * the skb and put it into the receive queue. | |
243 | */ | |
244 | static int macvtap_forward(struct net_device *dev, struct sk_buff *skb) | |
245 | { | |
246 | struct macvtap_queue *q = macvtap_get_queue(dev, skb); | |
247 | if (!q) | |
8a35747a HX |
248 | goto drop; |
249 | ||
250 | if (skb_queue_len(&q->sk.sk_receive_queue) >= dev->tx_queue_len) | |
251 | goto drop; | |
20d29d7a AB |
252 | |
253 | skb_queue_tail(&q->sk.sk_receive_queue, skb); | |
4a4771a5 | 254 | wake_up_interruptible_poll(sk_sleep(&q->sk), POLLIN | POLLRDNORM | POLLRDBAND); |
8a35747a HX |
255 | return NET_RX_SUCCESS; |
256 | ||
257 | drop: | |
258 | kfree_skb(skb); | |
259 | return NET_RX_DROP; | |
20d29d7a AB |
260 | } |
261 | ||
262 | /* | |
263 | * Receive is for data from the external interface (lowerdev), | |
264 | * in case of macvtap, we can treat that the same way as | |
265 | * forward, which macvlan cannot. | |
266 | */ | |
267 | static int macvtap_receive(struct sk_buff *skb) | |
268 | { | |
269 | skb_push(skb, ETH_HLEN); | |
270 | return macvtap_forward(skb->dev, skb); | |
271 | } | |
272 | ||
273 | static int macvtap_newlink(struct net *src_net, | |
274 | struct net_device *dev, | |
275 | struct nlattr *tb[], | |
276 | struct nlattr *data[]) | |
277 | { | |
278 | struct device *classdev; | |
279 | dev_t devt; | |
280 | int err; | |
281 | ||
282 | err = macvlan_common_newlink(src_net, dev, tb, data, | |
283 | macvtap_receive, macvtap_forward); | |
284 | if (err) | |
285 | goto out; | |
286 | ||
287 | devt = MKDEV(MAJOR(macvtap_major), dev->ifindex); | |
288 | ||
289 | classdev = device_create(macvtap_class, &dev->dev, devt, | |
290 | dev, "tap%d", dev->ifindex); | |
291 | if (IS_ERR(classdev)) { | |
292 | err = PTR_ERR(classdev); | |
293 | macvtap_del_queues(dev); | |
294 | } | |
295 | ||
296 | out: | |
297 | return err; | |
298 | } | |
299 | ||
300 | static void macvtap_dellink(struct net_device *dev, | |
301 | struct list_head *head) | |
302 | { | |
303 | device_destroy(macvtap_class, | |
304 | MKDEV(MAJOR(macvtap_major), dev->ifindex)); | |
305 | ||
306 | macvtap_del_queues(dev); | |
307 | macvlan_dellink(dev, head); | |
308 | } | |
309 | ||
8a35747a HX |
310 | static void macvtap_setup(struct net_device *dev) |
311 | { | |
312 | macvlan_common_setup(dev); | |
313 | dev->tx_queue_len = TUN_READQ_SIZE; | |
314 | } | |
315 | ||
20d29d7a AB |
316 | static struct rtnl_link_ops macvtap_link_ops __read_mostly = { |
317 | .kind = "macvtap", | |
8a35747a | 318 | .setup = macvtap_setup, |
20d29d7a AB |
319 | .newlink = macvtap_newlink, |
320 | .dellink = macvtap_dellink, | |
321 | }; | |
322 | ||
323 | ||
324 | static void macvtap_sock_write_space(struct sock *sk) | |
325 | { | |
43815482 ED |
326 | wait_queue_head_t *wqueue; |
327 | ||
20d29d7a AB |
328 | if (!sock_writeable(sk) || |
329 | !test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags)) | |
330 | return; | |
331 | ||
43815482 ED |
332 | wqueue = sk_sleep(sk); |
333 | if (wqueue && waitqueue_active(wqueue)) | |
334 | wake_up_interruptible_poll(wqueue, POLLOUT | POLLWRNORM | POLLWRBAND); | |
20d29d7a AB |
335 | } |
336 | ||
337 | static int macvtap_open(struct inode *inode, struct file *file) | |
338 | { | |
339 | struct net *net = current->nsproxy->net_ns; | |
340 | struct net_device *dev = dev_get_by_index(net, iminor(inode)); | |
341 | struct macvtap_queue *q; | |
342 | int err; | |
343 | ||
344 | err = -ENODEV; | |
345 | if (!dev) | |
346 | goto out; | |
347 | ||
348 | /* check if this is a macvtap device */ | |
349 | err = -EINVAL; | |
350 | if (dev->rtnl_link_ops != &macvtap_link_ops) | |
351 | goto out; | |
352 | ||
353 | err = -ENOMEM; | |
354 | q = (struct macvtap_queue *)sk_alloc(net, AF_UNSPEC, GFP_KERNEL, | |
355 | &macvtap_proto); | |
356 | if (!q) | |
357 | goto out; | |
358 | ||
43815482 ED |
359 | q->sock.wq = &q->wq; |
360 | init_waitqueue_head(&q->wq.wait); | |
20d29d7a AB |
361 | q->sock.type = SOCK_RAW; |
362 | q->sock.state = SS_CONNECTED; | |
501c774c AB |
363 | q->sock.file = file; |
364 | q->sock.ops = &macvtap_socket_ops; | |
20d29d7a | 365 | sock_init_data(&q->sock, &q->sk); |
20d29d7a | 366 | q->sk.sk_write_space = macvtap_sock_write_space; |
b9fb9ee0 | 367 | q->flags = IFF_VNET_HDR | IFF_NO_PI | IFF_TAP; |
55afbd08 | 368 | q->vnet_hdr_sz = sizeof(struct virtio_net_hdr); |
20d29d7a AB |
369 | |
370 | err = macvtap_set_queue(dev, file, q); | |
371 | if (err) | |
372 | sock_put(&q->sk); | |
373 | ||
374 | out: | |
375 | if (dev) | |
376 | dev_put(dev); | |
377 | ||
378 | return err; | |
379 | } | |
380 | ||
381 | static int macvtap_release(struct inode *inode, struct file *file) | |
382 | { | |
02df55d2 AB |
383 | struct macvtap_queue *q = file->private_data; |
384 | macvtap_put_queue(q); | |
20d29d7a AB |
385 | return 0; |
386 | } | |
387 | ||
388 | static unsigned int macvtap_poll(struct file *file, poll_table * wait) | |
389 | { | |
02df55d2 | 390 | struct macvtap_queue *q = file->private_data; |
20d29d7a AB |
391 | unsigned int mask = POLLERR; |
392 | ||
393 | if (!q) | |
394 | goto out; | |
395 | ||
396 | mask = 0; | |
43815482 | 397 | poll_wait(file, &q->wq.wait, wait); |
20d29d7a AB |
398 | |
399 | if (!skb_queue_empty(&q->sk.sk_receive_queue)) | |
400 | mask |= POLLIN | POLLRDNORM; | |
401 | ||
402 | if (sock_writeable(&q->sk) || | |
403 | (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &q->sock.flags) && | |
404 | sock_writeable(&q->sk))) | |
405 | mask |= POLLOUT | POLLWRNORM; | |
406 | ||
407 | out: | |
20d29d7a AB |
408 | return mask; |
409 | } | |
410 | ||
b9fb9ee0 AB |
411 | static inline struct sk_buff *macvtap_alloc_skb(struct sock *sk, size_t prepad, |
412 | size_t len, size_t linear, | |
413 | int noblock, int *err) | |
414 | { | |
415 | struct sk_buff *skb; | |
416 | ||
417 | /* Under a page? Don't bother with paged skb. */ | |
418 | if (prepad + len < PAGE_SIZE || !linear) | |
419 | linear = len; | |
420 | ||
421 | skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock, | |
422 | err); | |
423 | if (!skb) | |
424 | return NULL; | |
425 | ||
426 | skb_reserve(skb, prepad); | |
427 | skb_put(skb, linear); | |
428 | skb->data_len = len - linear; | |
429 | skb->len += len - linear; | |
430 | ||
431 | return skb; | |
432 | } | |
433 | ||
434 | /* | |
435 | * macvtap_skb_from_vnet_hdr and macvtap_skb_to_vnet_hdr should | |
436 | * be shared with the tun/tap driver. | |
437 | */ | |
438 | static int macvtap_skb_from_vnet_hdr(struct sk_buff *skb, | |
439 | struct virtio_net_hdr *vnet_hdr) | |
440 | { | |
441 | unsigned short gso_type = 0; | |
442 | if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) { | |
443 | switch (vnet_hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { | |
444 | case VIRTIO_NET_HDR_GSO_TCPV4: | |
445 | gso_type = SKB_GSO_TCPV4; | |
446 | break; | |
447 | case VIRTIO_NET_HDR_GSO_TCPV6: | |
448 | gso_type = SKB_GSO_TCPV6; | |
449 | break; | |
450 | case VIRTIO_NET_HDR_GSO_UDP: | |
451 | gso_type = SKB_GSO_UDP; | |
452 | break; | |
453 | default: | |
454 | return -EINVAL; | |
455 | } | |
456 | ||
457 | if (vnet_hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN) | |
458 | gso_type |= SKB_GSO_TCP_ECN; | |
459 | ||
460 | if (vnet_hdr->gso_size == 0) | |
461 | return -EINVAL; | |
462 | } | |
463 | ||
464 | if (vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { | |
465 | if (!skb_partial_csum_set(skb, vnet_hdr->csum_start, | |
466 | vnet_hdr->csum_offset)) | |
467 | return -EINVAL; | |
468 | } | |
469 | ||
470 | if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) { | |
471 | skb_shinfo(skb)->gso_size = vnet_hdr->gso_size; | |
472 | skb_shinfo(skb)->gso_type = gso_type; | |
473 | ||
474 | /* Header must be checked, and gso_segs computed. */ | |
475 | skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; | |
476 | skb_shinfo(skb)->gso_segs = 0; | |
477 | } | |
478 | return 0; | |
479 | } | |
480 | ||
481 | static int macvtap_skb_to_vnet_hdr(const struct sk_buff *skb, | |
482 | struct virtio_net_hdr *vnet_hdr) | |
483 | { | |
484 | memset(vnet_hdr, 0, sizeof(*vnet_hdr)); | |
485 | ||
486 | if (skb_is_gso(skb)) { | |
487 | struct skb_shared_info *sinfo = skb_shinfo(skb); | |
488 | ||
489 | /* This is a hint as to how much should be linear. */ | |
490 | vnet_hdr->hdr_len = skb_headlen(skb); | |
491 | vnet_hdr->gso_size = sinfo->gso_size; | |
492 | if (sinfo->gso_type & SKB_GSO_TCPV4) | |
493 | vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4; | |
494 | else if (sinfo->gso_type & SKB_GSO_TCPV6) | |
495 | vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6; | |
496 | else if (sinfo->gso_type & SKB_GSO_UDP) | |
497 | vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP; | |
498 | else | |
499 | BUG(); | |
500 | if (sinfo->gso_type & SKB_GSO_TCP_ECN) | |
501 | vnet_hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN; | |
502 | } else | |
503 | vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE; | |
504 | ||
505 | if (skb->ip_summed == CHECKSUM_PARTIAL) { | |
506 | vnet_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; | |
55508d60 | 507 | vnet_hdr->csum_start = skb_checksum_start_offset(skb); |
b9fb9ee0 AB |
508 | vnet_hdr->csum_offset = skb->csum_offset; |
509 | } /* else everything is zero */ | |
510 | ||
511 | return 0; | |
512 | } | |
513 | ||
514 | ||
20d29d7a AB |
515 | /* Get packet from user space buffer */ |
516 | static ssize_t macvtap_get_user(struct macvtap_queue *q, | |
517 | const struct iovec *iv, size_t count, | |
518 | int noblock) | |
519 | { | |
520 | struct sk_buff *skb; | |
02df55d2 | 521 | struct macvlan_dev *vlan; |
20d29d7a AB |
522 | size_t len = count; |
523 | int err; | |
b9fb9ee0 AB |
524 | struct virtio_net_hdr vnet_hdr = { 0 }; |
525 | int vnet_hdr_len = 0; | |
526 | ||
527 | if (q->flags & IFF_VNET_HDR) { | |
55afbd08 | 528 | vnet_hdr_len = q->vnet_hdr_sz; |
b9fb9ee0 AB |
529 | |
530 | err = -EINVAL; | |
531 | if ((len -= vnet_hdr_len) < 0) | |
532 | goto err; | |
533 | ||
534 | err = memcpy_fromiovecend((void *)&vnet_hdr, iv, 0, | |
55afbd08 | 535 | sizeof(vnet_hdr)); |
b9fb9ee0 AB |
536 | if (err < 0) |
537 | goto err; | |
538 | if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && | |
539 | vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 > | |
540 | vnet_hdr.hdr_len) | |
541 | vnet_hdr.hdr_len = vnet_hdr.csum_start + | |
542 | vnet_hdr.csum_offset + 2; | |
543 | err = -EINVAL; | |
544 | if (vnet_hdr.hdr_len > len) | |
545 | goto err; | |
546 | } | |
20d29d7a | 547 | |
b9fb9ee0 | 548 | err = -EINVAL; |
20d29d7a | 549 | if (unlikely(len < ETH_HLEN)) |
b9fb9ee0 | 550 | goto err; |
20d29d7a | 551 | |
b9fb9ee0 AB |
552 | skb = macvtap_alloc_skb(&q->sk, NET_IP_ALIGN, len, vnet_hdr.hdr_len, |
553 | noblock, &err); | |
02df55d2 AB |
554 | if (!skb) |
555 | goto err; | |
20d29d7a | 556 | |
b9fb9ee0 | 557 | err = skb_copy_datagram_from_iovec(skb, 0, iv, vnet_hdr_len, len); |
02df55d2 | 558 | if (err) |
b9fb9ee0 | 559 | goto err_kfree; |
20d29d7a AB |
560 | |
561 | skb_set_network_header(skb, ETH_HLEN); | |
b9fb9ee0 AB |
562 | skb_reset_mac_header(skb); |
563 | skb->protocol = eth_hdr(skb)->h_proto; | |
564 | ||
565 | if (vnet_hdr_len) { | |
566 | err = macvtap_skb_from_vnet_hdr(skb, &vnet_hdr); | |
567 | if (err) | |
568 | goto err_kfree; | |
569 | } | |
570 | ||
02df55d2 AB |
571 | rcu_read_lock_bh(); |
572 | vlan = rcu_dereference(q->vlan); | |
573 | if (vlan) | |
574 | macvlan_start_xmit(skb, vlan->dev); | |
575 | else | |
576 | kfree_skb(skb); | |
577 | rcu_read_unlock_bh(); | |
20d29d7a AB |
578 | |
579 | return count; | |
02df55d2 | 580 | |
b9fb9ee0 AB |
581 | err_kfree: |
582 | kfree_skb(skb); | |
583 | ||
02df55d2 AB |
584 | err: |
585 | rcu_read_lock_bh(); | |
586 | vlan = rcu_dereference(q->vlan); | |
587 | if (vlan) | |
b9fb9ee0 | 588 | netdev_get_tx_queue(vlan->dev, 0)->tx_dropped++; |
02df55d2 AB |
589 | rcu_read_unlock_bh(); |
590 | ||
02df55d2 | 591 | return err; |
20d29d7a AB |
592 | } |
593 | ||
594 | static ssize_t macvtap_aio_write(struct kiocb *iocb, const struct iovec *iv, | |
595 | unsigned long count, loff_t pos) | |
596 | { | |
597 | struct file *file = iocb->ki_filp; | |
598 | ssize_t result = -ENOLINK; | |
02df55d2 | 599 | struct macvtap_queue *q = file->private_data; |
20d29d7a AB |
600 | |
601 | result = macvtap_get_user(q, iv, iov_length(iv, count), | |
602 | file->f_flags & O_NONBLOCK); | |
20d29d7a AB |
603 | return result; |
604 | } | |
605 | ||
606 | /* Put packet to the user space buffer */ | |
607 | static ssize_t macvtap_put_user(struct macvtap_queue *q, | |
608 | const struct sk_buff *skb, | |
609 | const struct iovec *iv, int len) | |
610 | { | |
02df55d2 | 611 | struct macvlan_dev *vlan; |
20d29d7a | 612 | int ret; |
b9fb9ee0 AB |
613 | int vnet_hdr_len = 0; |
614 | ||
615 | if (q->flags & IFF_VNET_HDR) { | |
616 | struct virtio_net_hdr vnet_hdr; | |
55afbd08 | 617 | vnet_hdr_len = q->vnet_hdr_sz; |
b9fb9ee0 AB |
618 | if ((len -= vnet_hdr_len) < 0) |
619 | return -EINVAL; | |
620 | ||
621 | ret = macvtap_skb_to_vnet_hdr(skb, &vnet_hdr); | |
622 | if (ret) | |
623 | return ret; | |
624 | ||
55afbd08 | 625 | if (memcpy_toiovecend(iv, (void *)&vnet_hdr, 0, sizeof(vnet_hdr))) |
b9fb9ee0 AB |
626 | return -EFAULT; |
627 | } | |
20d29d7a AB |
628 | |
629 | len = min_t(int, skb->len, len); | |
630 | ||
b9fb9ee0 | 631 | ret = skb_copy_datagram_const_iovec(skb, 0, iv, vnet_hdr_len, len); |
20d29d7a | 632 | |
02df55d2 AB |
633 | rcu_read_lock_bh(); |
634 | vlan = rcu_dereference(q->vlan); | |
501c774c AB |
635 | if (vlan) |
636 | macvlan_count_rx(vlan, len, ret == 0, 0); | |
02df55d2 | 637 | rcu_read_unlock_bh(); |
20d29d7a | 638 | |
b9fb9ee0 | 639 | return ret ? ret : (len + vnet_hdr_len); |
20d29d7a AB |
640 | } |
641 | ||
501c774c AB |
642 | static ssize_t macvtap_do_read(struct macvtap_queue *q, struct kiocb *iocb, |
643 | const struct iovec *iv, unsigned long len, | |
644 | int noblock) | |
20d29d7a | 645 | { |
20d29d7a AB |
646 | DECLARE_WAITQUEUE(wait, current); |
647 | struct sk_buff *skb; | |
501c774c | 648 | ssize_t ret = 0; |
20d29d7a | 649 | |
4a4771a5 | 650 | add_wait_queue(sk_sleep(&q->sk), &wait); |
20d29d7a AB |
651 | while (len) { |
652 | current->state = TASK_INTERRUPTIBLE; | |
653 | ||
654 | /* Read frames from the queue */ | |
655 | skb = skb_dequeue(&q->sk.sk_receive_queue); | |
656 | if (!skb) { | |
501c774c | 657 | if (noblock) { |
20d29d7a AB |
658 | ret = -EAGAIN; |
659 | break; | |
660 | } | |
661 | if (signal_pending(current)) { | |
662 | ret = -ERESTARTSYS; | |
663 | break; | |
664 | } | |
665 | /* Nothing to read, let's sleep */ | |
666 | schedule(); | |
667 | continue; | |
668 | } | |
669 | ret = macvtap_put_user(q, skb, iv, len); | |
670 | kfree_skb(skb); | |
671 | break; | |
672 | } | |
673 | ||
674 | current->state = TASK_RUNNING; | |
4a4771a5 | 675 | remove_wait_queue(sk_sleep(&q->sk), &wait); |
501c774c AB |
676 | return ret; |
677 | } | |
678 | ||
679 | static ssize_t macvtap_aio_read(struct kiocb *iocb, const struct iovec *iv, | |
680 | unsigned long count, loff_t pos) | |
681 | { | |
682 | struct file *file = iocb->ki_filp; | |
683 | struct macvtap_queue *q = file->private_data; | |
684 | ssize_t len, ret = 0; | |
20d29d7a | 685 | |
501c774c AB |
686 | len = iov_length(iv, count); |
687 | if (len < 0) { | |
688 | ret = -EINVAL; | |
689 | goto out; | |
690 | } | |
691 | ||
692 | ret = macvtap_do_read(q, iocb, iv, len, file->f_flags & O_NONBLOCK); | |
693 | ret = min_t(ssize_t, ret, len); /* XXX copied from tun.c. Why? */ | |
20d29d7a | 694 | out: |
20d29d7a AB |
695 | return ret; |
696 | } | |
697 | ||
698 | /* | |
699 | * provide compatibility with generic tun/tap interface | |
700 | */ | |
701 | static long macvtap_ioctl(struct file *file, unsigned int cmd, | |
702 | unsigned long arg) | |
703 | { | |
02df55d2 AB |
704 | struct macvtap_queue *q = file->private_data; |
705 | struct macvlan_dev *vlan; | |
20d29d7a AB |
706 | void __user *argp = (void __user *)arg; |
707 | struct ifreq __user *ifr = argp; | |
708 | unsigned int __user *up = argp; | |
709 | unsigned int u; | |
55afbd08 MT |
710 | int __user *sp = argp; |
711 | int s; | |
02df55d2 | 712 | int ret; |
20d29d7a AB |
713 | |
714 | switch (cmd) { | |
715 | case TUNSETIFF: | |
716 | /* ignore the name, just look at flags */ | |
717 | if (get_user(u, &ifr->ifr_flags)) | |
718 | return -EFAULT; | |
b9fb9ee0 AB |
719 | |
720 | ret = 0; | |
721 | if ((u & ~IFF_VNET_HDR) != (IFF_NO_PI | IFF_TAP)) | |
722 | ret = -EINVAL; | |
723 | else | |
724 | q->flags = u; | |
725 | ||
726 | return ret; | |
20d29d7a AB |
727 | |
728 | case TUNGETIFF: | |
02df55d2 AB |
729 | rcu_read_lock_bh(); |
730 | vlan = rcu_dereference(q->vlan); | |
731 | if (vlan) | |
732 | dev_hold(vlan->dev); | |
733 | rcu_read_unlock_bh(); | |
734 | ||
735 | if (!vlan) | |
20d29d7a | 736 | return -ENOLINK; |
20d29d7a | 737 | |
02df55d2 | 738 | ret = 0; |
20d29d7a | 739 | if (copy_to_user(&ifr->ifr_name, q->vlan->dev->name, IFNAMSIZ) || |
b9fb9ee0 | 740 | put_user(q->flags, &ifr->ifr_flags)) |
02df55d2 AB |
741 | ret = -EFAULT; |
742 | dev_put(vlan->dev); | |
743 | return ret; | |
20d29d7a AB |
744 | |
745 | case TUNGETFEATURES: | |
b9fb9ee0 | 746 | if (put_user(IFF_TAP | IFF_NO_PI | IFF_VNET_HDR, up)) |
20d29d7a AB |
747 | return -EFAULT; |
748 | return 0; | |
749 | ||
750 | case TUNSETSNDBUF: | |
751 | if (get_user(u, up)) | |
752 | return -EFAULT; | |
753 | ||
20d29d7a | 754 | q->sk.sk_sndbuf = u; |
20d29d7a AB |
755 | return 0; |
756 | ||
55afbd08 MT |
757 | case TUNGETVNETHDRSZ: |
758 | s = q->vnet_hdr_sz; | |
759 | if (put_user(s, sp)) | |
760 | return -EFAULT; | |
761 | return 0; | |
762 | ||
763 | case TUNSETVNETHDRSZ: | |
764 | if (get_user(s, sp)) | |
765 | return -EFAULT; | |
766 | if (s < (int)sizeof(struct virtio_net_hdr)) | |
767 | return -EINVAL; | |
768 | ||
769 | q->vnet_hdr_sz = s; | |
770 | return 0; | |
771 | ||
20d29d7a AB |
772 | case TUNSETOFFLOAD: |
773 | /* let the user check for future flags */ | |
774 | if (arg & ~(TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6 | | |
b9fb9ee0 | 775 | TUN_F_TSO_ECN | TUN_F_UFO)) |
20d29d7a AB |
776 | return -EINVAL; |
777 | ||
b9fb9ee0 AB |
778 | /* TODO: only accept frames with the features that |
779 | got enabled for forwarded frames */ | |
780 | if (!(q->flags & IFF_VNET_HDR)) | |
781 | return -EINVAL; | |
20d29d7a AB |
782 | return 0; |
783 | ||
784 | default: | |
785 | return -EINVAL; | |
786 | } | |
787 | } | |
788 | ||
789 | #ifdef CONFIG_COMPAT | |
790 | static long macvtap_compat_ioctl(struct file *file, unsigned int cmd, | |
791 | unsigned long arg) | |
792 | { | |
793 | return macvtap_ioctl(file, cmd, (unsigned long)compat_ptr(arg)); | |
794 | } | |
795 | #endif | |
796 | ||
797 | static const struct file_operations macvtap_fops = { | |
798 | .owner = THIS_MODULE, | |
799 | .open = macvtap_open, | |
800 | .release = macvtap_release, | |
801 | .aio_read = macvtap_aio_read, | |
802 | .aio_write = macvtap_aio_write, | |
803 | .poll = macvtap_poll, | |
804 | .llseek = no_llseek, | |
805 | .unlocked_ioctl = macvtap_ioctl, | |
806 | #ifdef CONFIG_COMPAT | |
807 | .compat_ioctl = macvtap_compat_ioctl, | |
808 | #endif | |
809 | }; | |
810 | ||
501c774c AB |
811 | static int macvtap_sendmsg(struct kiocb *iocb, struct socket *sock, |
812 | struct msghdr *m, size_t total_len) | |
813 | { | |
814 | struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock); | |
815 | return macvtap_get_user(q, m->msg_iov, total_len, | |
816 | m->msg_flags & MSG_DONTWAIT); | |
817 | } | |
818 | ||
819 | static int macvtap_recvmsg(struct kiocb *iocb, struct socket *sock, | |
820 | struct msghdr *m, size_t total_len, | |
821 | int flags) | |
822 | { | |
823 | struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock); | |
824 | int ret; | |
825 | if (flags & ~(MSG_DONTWAIT|MSG_TRUNC)) | |
826 | return -EINVAL; | |
827 | ret = macvtap_do_read(q, iocb, m->msg_iov, total_len, | |
828 | flags & MSG_DONTWAIT); | |
829 | if (ret > total_len) { | |
830 | m->msg_flags |= MSG_TRUNC; | |
831 | ret = flags & MSG_TRUNC ? ret : total_len; | |
832 | } | |
833 | return ret; | |
834 | } | |
835 | ||
836 | /* Ops structure to mimic raw sockets with tun */ | |
837 | static const struct proto_ops macvtap_socket_ops = { | |
838 | .sendmsg = macvtap_sendmsg, | |
839 | .recvmsg = macvtap_recvmsg, | |
840 | }; | |
841 | ||
842 | /* Get an underlying socket object from tun file. Returns error unless file is | |
843 | * attached to a device. The returned object works like a packet socket, it | |
844 | * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for | |
845 | * holding a reference to the file for as long as the socket is in use. */ | |
846 | struct socket *macvtap_get_socket(struct file *file) | |
847 | { | |
848 | struct macvtap_queue *q; | |
849 | if (file->f_op != &macvtap_fops) | |
850 | return ERR_PTR(-EINVAL); | |
851 | q = file->private_data; | |
852 | if (!q) | |
853 | return ERR_PTR(-EBADFD); | |
854 | return &q->sock; | |
855 | } | |
856 | EXPORT_SYMBOL_GPL(macvtap_get_socket); | |
857 | ||
20d29d7a AB |
858 | static int macvtap_init(void) |
859 | { | |
860 | int err; | |
861 | ||
862 | err = alloc_chrdev_region(&macvtap_major, 0, | |
863 | MACVTAP_NUM_DEVS, "macvtap"); | |
864 | if (err) | |
865 | goto out1; | |
866 | ||
867 | cdev_init(&macvtap_cdev, &macvtap_fops); | |
868 | err = cdev_add(&macvtap_cdev, macvtap_major, MACVTAP_NUM_DEVS); | |
869 | if (err) | |
870 | goto out2; | |
871 | ||
872 | macvtap_class = class_create(THIS_MODULE, "macvtap"); | |
873 | if (IS_ERR(macvtap_class)) { | |
874 | err = PTR_ERR(macvtap_class); | |
875 | goto out3; | |
876 | } | |
877 | ||
878 | err = macvlan_link_register(&macvtap_link_ops); | |
879 | if (err) | |
880 | goto out4; | |
881 | ||
882 | return 0; | |
883 | ||
884 | out4: | |
885 | class_unregister(macvtap_class); | |
886 | out3: | |
887 | cdev_del(&macvtap_cdev); | |
888 | out2: | |
889 | unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS); | |
890 | out1: | |
891 | return err; | |
892 | } | |
893 | module_init(macvtap_init); | |
894 | ||
895 | static void macvtap_exit(void) | |
896 | { | |
897 | rtnl_link_unregister(&macvtap_link_ops); | |
898 | class_unregister(macvtap_class); | |
899 | cdev_del(&macvtap_cdev); | |
900 | unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS); | |
901 | } | |
902 | module_exit(macvtap_exit); | |
903 | ||
904 | MODULE_ALIAS_RTNL_LINK("macvtap"); | |
905 | MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>"); | |
906 | MODULE_LICENSE("GPL"); |