Commit | Line | Data |
---|---|---|
09c434b8 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
20d29d7a | 2 | #include <linux/etherdevice.h> |
6fe3faf8 | 3 | #include <linux/if_tap.h> |
f09e2249 | 4 | #include <linux/if_vlan.h> |
20d29d7a AB |
5 | #include <linux/interrupt.h> |
6 | #include <linux/nsproxy.h> | |
7 | #include <linux/compat.h> | |
8 | #include <linux/if_tun.h> | |
9 | #include <linux/module.h> | |
10 | #include <linux/skbuff.h> | |
11 | #include <linux/cache.h> | |
c3edc401 | 12 | #include <linux/sched/signal.h> |
20d29d7a | 13 | #include <linux/types.h> |
5a0e3ad6 | 14 | #include <linux/slab.h> |
20d29d7a AB |
15 | #include <linux/wait.h> |
16 | #include <linux/cdev.h> | |
40401530 | 17 | #include <linux/idr.h> |
20d29d7a | 18 | #include <linux/fs.h> |
6c36d2e2 | 19 | #include <linux/uio.h> |
20d29d7a AB |
20 | |
21 | #include <net/net_namespace.h> | |
22 | #include <net/rtnetlink.h> | |
23 | #include <net/sock.h> | |
b9fb9ee0 | 24 | #include <linux/virtio_net.h> |
362899b8 | 25 | #include <linux/skb_array.h> |
20d29d7a | 26 | |
635b8c8e | 27 | #define TAP_IFFEATURES (IFF_VNET_HDR | IFF_MULTI_QUEUE) |
01b07fb3 | 28 | |
635b8c8e SG |
29 | #define TAP_VNET_LE 0x80000000 |
30 | #define TAP_VNET_BE 0x40000000 | |
8b8e658b GK |
31 | |
32 | #ifdef CONFIG_TUN_VNET_CROSS_LE | |
635b8c8e | 33 | static inline bool tap_legacy_is_little_endian(struct tap_queue *q) |
8b8e658b | 34 | { |
635b8c8e | 35 | return q->flags & TAP_VNET_BE ? false : |
8b8e658b GK |
36 | virtio_legacy_is_little_endian(); |
37 | } | |
38 | ||
635b8c8e | 39 | static long tap_get_vnet_be(struct tap_queue *q, int __user *sp) |
8b8e658b | 40 | { |
635b8c8e | 41 | int s = !!(q->flags & TAP_VNET_BE); |
8b8e658b GK |
42 | |
43 | if (put_user(s, sp)) | |
44 | return -EFAULT; | |
45 | ||
46 | return 0; | |
47 | } | |
48 | ||
635b8c8e | 49 | static long tap_set_vnet_be(struct tap_queue *q, int __user *sp) |
8b8e658b GK |
50 | { |
51 | int s; | |
52 | ||
53 | if (get_user(s, sp)) | |
54 | return -EFAULT; | |
55 | ||
56 | if (s) | |
635b8c8e | 57 | q->flags |= TAP_VNET_BE; |
8b8e658b | 58 | else |
635b8c8e | 59 | q->flags &= ~TAP_VNET_BE; |
8b8e658b GK |
60 | |
61 | return 0; | |
62 | } | |
63 | #else | |
635b8c8e | 64 | static inline bool tap_legacy_is_little_endian(struct tap_queue *q) |
8b8e658b GK |
65 | { |
66 | return virtio_legacy_is_little_endian(); | |
67 | } | |
68 | ||
635b8c8e | 69 | static long tap_get_vnet_be(struct tap_queue *q, int __user *argp) |
8b8e658b GK |
70 | { |
71 | return -EINVAL; | |
72 | } | |
73 | ||
635b8c8e | 74 | static long tap_set_vnet_be(struct tap_queue *q, int __user *argp) |
8b8e658b GK |
75 | { |
76 | return -EINVAL; | |
77 | } | |
78 | #endif /* CONFIG_TUN_VNET_CROSS_LE */ | |
6ae7feb3 | 79 | |
635b8c8e | 80 | static inline bool tap_is_little_endian(struct tap_queue *q) |
5b11e15f | 81 | { |
635b8c8e SG |
82 | return q->flags & TAP_VNET_LE || |
83 | tap_legacy_is_little_endian(q); | |
5b11e15f | 84 | } |
6ae7feb3 | 85 | |
635b8c8e | 86 | static inline u16 tap16_to_cpu(struct tap_queue *q, __virtio16 val) |
6ae7feb3 | 87 | { |
635b8c8e | 88 | return __virtio16_to_cpu(tap_is_little_endian(q), val); |
6ae7feb3 MT |
89 | } |
90 | ||
635b8c8e | 91 | static inline __virtio16 cpu_to_tap16(struct tap_queue *q, u16 val) |
6ae7feb3 | 92 | { |
635b8c8e | 93 | return __cpu_to_virtio16(tap_is_little_endian(q), val); |
6ae7feb3 MT |
94 | } |
95 | ||
635b8c8e SG |
96 | static struct proto tap_proto = { |
97 | .name = "tap", | |
20d29d7a | 98 | .owner = THIS_MODULE, |
635b8c8e | 99 | .obj_size = sizeof(struct tap_queue), |
20d29d7a AB |
100 | }; |
101 | ||
635b8c8e | 102 | #define TAP_NUM_DEVS (1U << MINORBITS) |
d9f1f61c SG |
103 | |
104 | static LIST_HEAD(major_list); | |
105 | ||
ebc05ba7 | 106 | struct major_info { |
d9f1f61c | 107 | struct rcu_head rcu; |
ebc05ba7 SG |
108 | dev_t major; |
109 | struct idr minor_idr; | |
ffa423fb | 110 | spinlock_t minor_lock; |
ebc05ba7 | 111 | const char *device_name; |
d9f1f61c SG |
112 | struct list_head next; |
113 | }; | |
e09eff7f | 114 | |
97bc3633 | 115 | #define GOODCOPY_LEN 128 |
20d29d7a | 116 | |
635b8c8e | 117 | static const struct proto_ops tap_socket_ops; |
501c774c | 118 | |
2be5c767 | 119 | #define RX_OFFLOADS (NETIF_F_GRO | NETIF_F_LRO) |
f23d538b | 120 | #define TAP_FEATURES (NETIF_F_GSO | NETIF_F_SG | NETIF_F_FRAGLIST) |
a567dd62 | 121 | |
6fe3faf8 | 122 | static struct tap_dev *tap_dev_get_rcu(const struct net_device *dev) |
6acf54f1 VY |
123 | { |
124 | return rcu_dereference(dev->rx_handler_data); | |
125 | } | |
126 | ||
20d29d7a AB |
127 | /* |
128 | * RCU usage: | |
635b8c8e | 129 | * The tap_queue and the macvlan_dev are loosely coupled, the |
02df55d2 | 130 | * pointers from one to the other can only be read while rcu_read_lock |
441ac0fc | 131 | * or rtnl is held. |
20d29d7a | 132 | * |
635b8c8e | 133 | * Both the file and the macvlan_dev hold a reference on the tap_queue |
02df55d2 AB |
134 | * through sock_hold(&q->sk). When the macvlan_dev goes away first, |
135 | * q->vlan becomes inaccessible. When the files gets closed, | |
635b8c8e | 136 | * tap_get_queue() fails. |
20d29d7a | 137 | * |
02df55d2 AB |
138 | * There may still be references to the struct sock inside of the |
139 | * queue from outbound SKBs, but these never reference back to the | |
140 | * file or the dev. The data structure is freed through __sk_free | |
141 | * when both our references and any pending SKBs are gone. | |
20d29d7a | 142 | */ |
20d29d7a | 143 | |
6fe3faf8 | 144 | static int tap_enable_queue(struct tap_dev *tap, struct file *file, |
635b8c8e | 145 | struct tap_queue *q) |
815f236d | 146 | { |
815f236d JW |
147 | int err = -EINVAL; |
148 | ||
441ac0fc | 149 | ASSERT_RTNL(); |
815f236d JW |
150 | |
151 | if (q->enabled) | |
152 | goto out; | |
153 | ||
154 | err = 0; | |
6fe3faf8 SG |
155 | rcu_assign_pointer(tap->taps[tap->numvtaps], q); |
156 | q->queue_index = tap->numvtaps; | |
815f236d JW |
157 | q->enabled = true; |
158 | ||
6fe3faf8 | 159 | tap->numvtaps++; |
815f236d | 160 | out: |
815f236d JW |
161 | return err; |
162 | } | |
163 | ||
40b8fe45 | 164 | /* Requires RTNL */ |
6fe3faf8 | 165 | static int tap_set_queue(struct tap_dev *tap, struct file *file, |
635b8c8e | 166 | struct tap_queue *q) |
20d29d7a | 167 | { |
6fe3faf8 | 168 | if (tap->numqueues == MAX_TAP_QUEUES) |
40b8fe45 | 169 | return -EBUSY; |
20d29d7a | 170 | |
6fe3faf8 SG |
171 | rcu_assign_pointer(q->tap, tap); |
172 | rcu_assign_pointer(tap->taps[tap->numvtaps], q); | |
02df55d2 | 173 | sock_hold(&q->sk); |
20d29d7a AB |
174 | |
175 | q->file = file; | |
6fe3faf8 | 176 | q->queue_index = tap->numvtaps; |
815f236d | 177 | q->enabled = true; |
02df55d2 | 178 | file->private_data = q; |
6fe3faf8 | 179 | list_add_tail(&q->next, &tap->queue_list); |
20d29d7a | 180 | |
6fe3faf8 SG |
181 | tap->numvtaps++; |
182 | tap->numqueues++; | |
1565c7c1 | 183 | |
40b8fe45 | 184 | return 0; |
20d29d7a AB |
185 | } |
186 | ||
635b8c8e | 187 | static int tap_disable_queue(struct tap_queue *q) |
815f236d | 188 | { |
6fe3faf8 | 189 | struct tap_dev *tap; |
635b8c8e | 190 | struct tap_queue *nq; |
815f236d | 191 | |
441ac0fc | 192 | ASSERT_RTNL(); |
815f236d JW |
193 | if (!q->enabled) |
194 | return -EINVAL; | |
195 | ||
6fe3faf8 | 196 | tap = rtnl_dereference(q->tap); |
441ac0fc | 197 | |
6fe3faf8 | 198 | if (tap) { |
815f236d | 199 | int index = q->queue_index; |
6fe3faf8 SG |
200 | BUG_ON(index >= tap->numvtaps); |
201 | nq = rtnl_dereference(tap->taps[tap->numvtaps - 1]); | |
815f236d JW |
202 | nq->queue_index = index; |
203 | ||
6fe3faf8 SG |
204 | rcu_assign_pointer(tap->taps[index], nq); |
205 | RCU_INIT_POINTER(tap->taps[tap->numvtaps - 1], NULL); | |
815f236d JW |
206 | q->enabled = false; |
207 | ||
6fe3faf8 | 208 | tap->numvtaps--; |
815f236d JW |
209 | } |
210 | ||
211 | return 0; | |
212 | } | |
213 | ||
20d29d7a | 214 | /* |
02df55d2 AB |
215 | * The file owning the queue got closed, give up both |
216 | * the reference that the files holds as well as the | |
217 | * one from the macvlan_dev if that still exists. | |
20d29d7a AB |
218 | * |
219 | * Using the spinlock makes sure that we don't get | |
220 | * to the queue again after destroying it. | |
20d29d7a | 221 | */ |
635b8c8e | 222 | static void tap_put_queue(struct tap_queue *q) |
20d29d7a | 223 | { |
6fe3faf8 | 224 | struct tap_dev *tap; |
20d29d7a | 225 | |
441ac0fc | 226 | rtnl_lock(); |
6fe3faf8 | 227 | tap = rtnl_dereference(q->tap); |
441ac0fc | 228 | |
6fe3faf8 | 229 | if (tap) { |
815f236d | 230 | if (q->enabled) |
635b8c8e | 231 | BUG_ON(tap_disable_queue(q)); |
376b1aab | 232 | |
6fe3faf8 SG |
233 | tap->numqueues--; |
234 | RCU_INIT_POINTER(q->tap, NULL); | |
02df55d2 | 235 | sock_put(&q->sk); |
815f236d | 236 | list_del_init(&q->next); |
20d29d7a AB |
237 | } |
238 | ||
441ac0fc | 239 | rtnl_unlock(); |
20d29d7a AB |
240 | |
241 | synchronize_rcu(); | |
242 | sock_put(&q->sk); | |
243 | } | |
244 | ||
245 | /* | |
1565c7c1 KK |
246 | * Select a queue based on the rxq of the device on which this packet |
247 | * arrived. If the incoming device is not mq, calculate a flow hash | |
248 | * to select a queue. If all fails, find the first available queue. | |
249 | * Cache vlan->numvtaps since it can become zero during the execution | |
250 | * of this function. | |
20d29d7a | 251 | */ |
6fe3faf8 | 252 | static struct tap_queue *tap_get_queue(struct tap_dev *tap, |
635b8c8e | 253 | struct sk_buff *skb) |
20d29d7a | 254 | { |
6fe3faf8 | 255 | struct tap_queue *queue = NULL; |
815f236d JW |
256 | /* Access to taps array is protected by rcu, but access to numvtaps |
257 | * isn't. Below we use it to lookup a queue, but treat it as a hint | |
258 | * and validate that the result isn't NULL - in case we are | |
259 | * racing against queue removal. | |
260 | */ | |
6aa7de05 | 261 | int numvtaps = READ_ONCE(tap->numvtaps); |
1565c7c1 KK |
262 | __u32 rxq; |
263 | ||
264 | if (!numvtaps) | |
265 | goto out; | |
266 | ||
1b16bf42 JW |
267 | if (numvtaps == 1) |
268 | goto single; | |
269 | ||
ef0002b5 | 270 | /* Check if we can use flow to select a queue */ |
3958afa1 | 271 | rxq = skb_get_hash(skb); |
ef0002b5 | 272 | if (rxq) { |
6fe3faf8 | 273 | queue = rcu_dereference(tap->taps[rxq % numvtaps]); |
376b1aab | 274 | goto out; |
ef0002b5 KK |
275 | } |
276 | ||
1565c7c1 KK |
277 | if (likely(skb_rx_queue_recorded(skb))) { |
278 | rxq = skb_get_rx_queue(skb); | |
20d29d7a | 279 | |
1565c7c1 KK |
280 | while (unlikely(rxq >= numvtaps)) |
281 | rxq -= numvtaps; | |
282 | ||
6fe3faf8 | 283 | queue = rcu_dereference(tap->taps[rxq]); |
376b1aab | 284 | goto out; |
1565c7c1 KK |
285 | } |
286 | ||
1b16bf42 | 287 | single: |
6fe3faf8 | 288 | queue = rcu_dereference(tap->taps[0]); |
1565c7c1 | 289 | out: |
6fe3faf8 | 290 | return queue; |
20d29d7a AB |
291 | } |
292 | ||
02df55d2 AB |
293 | /* |
294 | * The net_device is going away, give up the reference | |
1565c7c1 KK |
295 | * that it holds on all queues and safely set the pointer |
296 | * from the queues to NULL. | |
02df55d2 | 297 | */ |
6fe3faf8 | 298 | void tap_del_queues(struct tap_dev *tap) |
20d29d7a | 299 | { |
635b8c8e | 300 | struct tap_queue *q, *tmp; |
02df55d2 | 301 | |
441ac0fc | 302 | ASSERT_RTNL(); |
6fe3faf8 | 303 | list_for_each_entry_safe(q, tmp, &tap->queue_list, next) { |
815f236d | 304 | list_del_init(&q->next); |
6fe3faf8 | 305 | RCU_INIT_POINTER(q->tap, NULL); |
815f236d | 306 | if (q->enabled) |
6fe3faf8 SG |
307 | tap->numvtaps--; |
308 | tap->numqueues--; | |
dfe816c5 | 309 | sock_put(&q->sk); |
564517e8 | 310 | } |
6fe3faf8 SG |
311 | BUG_ON(tap->numvtaps); |
312 | BUG_ON(tap->numqueues); | |
635b8c8e | 313 | /* guarantee that any future tap_set_queue will fail */ |
6fe3faf8 | 314 | tap->numvtaps = MAX_TAP_QUEUES; |
20d29d7a | 315 | } |
9a393b5d | 316 | EXPORT_SYMBOL_GPL(tap_del_queues); |
20d29d7a | 317 | |
635b8c8e | 318 | rx_handler_result_t tap_handle_frame(struct sk_buff **pskb) |
20d29d7a | 319 | { |
6acf54f1 VY |
320 | struct sk_buff *skb = *pskb; |
321 | struct net_device *dev = skb->dev; | |
6fe3faf8 | 322 | struct tap_dev *tap; |
635b8c8e | 323 | struct tap_queue *q; |
a567dd62 VY |
324 | netdev_features_t features = TAP_FEATURES; |
325 | ||
6fe3faf8 SG |
326 | tap = tap_dev_get_rcu(dev); |
327 | if (!tap) | |
6acf54f1 VY |
328 | return RX_HANDLER_PASS; |
329 | ||
6fe3faf8 | 330 | q = tap_get_queue(tap, skb); |
20d29d7a | 331 | if (!q) |
6acf54f1 | 332 | return RX_HANDLER_PASS; |
8a35747a | 333 | |
6acf54f1 VY |
334 | skb_push(skb, ETH_HLEN); |
335 | ||
3e4f8b78 | 336 | /* Apply the forward feature mask so that we perform segmentation |
e5733321 VY |
337 | * according to users wishes. This only works if VNET_HDR is |
338 | * enabled. | |
3e4f8b78 | 339 | */ |
e5733321 | 340 | if (q->flags & IFF_VNET_HDR) |
6fe3faf8 | 341 | features |= tap->tap_features; |
8b86a61d | 342 | if (netif_needs_gso(skb, features)) { |
3e4f8b78 | 343 | struct sk_buff *segs = __skb_gso_segment(skb, features, false); |
5643a552 | 344 | struct sk_buff *next; |
3e4f8b78 VY |
345 | |
346 | if (IS_ERR(segs)) | |
347 | goto drop; | |
348 | ||
349 | if (!segs) { | |
5990a305 | 350 | if (ptr_ring_produce(&q->ring, skb)) |
362899b8 | 351 | goto drop; |
3e4f8b78 VY |
352 | goto wake_up; |
353 | } | |
354 | ||
be0bd316 | 355 | consume_skb(skb); |
5643a552 JD |
356 | skb_list_walk_safe(segs, skb, next) { |
357 | skb_mark_not_on_list(skb); | |
358 | if (ptr_ring_produce(&q->ring, skb)) { | |
359 | kfree_skb(skb); | |
360 | kfree_skb_list(next); | |
362899b8 JW |
361 | break; |
362 | } | |
3e4f8b78 VY |
363 | } |
364 | } else { | |
cbdb0427 VY |
365 | /* If we receive a partial checksum and the tap side |
366 | * doesn't support checksum offload, compute the checksum. | |
367 | * Note: it doesn't matter which checksum feature to | |
a8e04698 | 368 | * check, we either support them all or none. |
cbdb0427 VY |
369 | */ |
370 | if (skb->ip_summed == CHECKSUM_PARTIAL && | |
a188222b | 371 | !(features & NETIF_F_CSUM_MASK) && |
cbdb0427 VY |
372 | skb_checksum_help(skb)) |
373 | goto drop; | |
5990a305 | 374 | if (ptr_ring_produce(&q->ring, skb)) |
362899b8 | 375 | goto drop; |
3e4f8b78 VY |
376 | } |
377 | ||
378 | wake_up: | |
a9a08845 | 379 | wake_up_interruptible_poll(sk_sleep(&q->sk), EPOLLIN | EPOLLRDNORM | EPOLLRDBAND); |
6acf54f1 | 380 | return RX_HANDLER_CONSUMED; |
8a35747a HX |
381 | |
382 | drop: | |
6acf54f1 | 383 | /* Count errors/drops only here, thus don't care about args. */ |
6fe3faf8 SG |
384 | if (tap->count_rx_dropped) |
385 | tap->count_rx_dropped(tap); | |
8a35747a | 386 | kfree_skb(skb); |
6acf54f1 | 387 | return RX_HANDLER_CONSUMED; |
20d29d7a | 388 | } |
9a393b5d | 389 | EXPORT_SYMBOL_GPL(tap_handle_frame); |
20d29d7a | 390 | |
d9f1f61c SG |
391 | static struct major_info *tap_get_major(int major) |
392 | { | |
393 | struct major_info *tap_major; | |
394 | ||
395 | list_for_each_entry_rcu(tap_major, &major_list, next) { | |
396 | if (tap_major->major == major) | |
397 | return tap_major; | |
398 | } | |
399 | ||
400 | return NULL; | |
401 | } | |
402 | ||
403 | int tap_get_minor(dev_t major, struct tap_dev *tap) | |
e09eff7f EB |
404 | { |
405 | int retval = -ENOMEM; | |
d9f1f61c SG |
406 | struct major_info *tap_major; |
407 | ||
408 | rcu_read_lock(); | |
409 | tap_major = tap_get_major(MAJOR(major)); | |
410 | if (!tap_major) { | |
411 | retval = -EINVAL; | |
412 | goto unlock; | |
413 | } | |
e09eff7f | 414 | |
ffa423fb WC |
415 | spin_lock(&tap_major->minor_lock); |
416 | retval = idr_alloc(&tap_major->minor_idr, tap, 1, TAP_NUM_DEVS, GFP_ATOMIC); | |
ec09ebc1 | 417 | if (retval >= 0) { |
6fe3faf8 | 418 | tap->minor = retval; |
ec09ebc1 | 419 | } else if (retval == -ENOSPC) { |
6fe3faf8 | 420 | netdev_err(tap->dev, "Too many tap devices\n"); |
e09eff7f | 421 | retval = -EINVAL; |
e09eff7f | 422 | } |
ffa423fb | 423 | spin_unlock(&tap_major->minor_lock); |
d9f1f61c SG |
424 | |
425 | unlock: | |
426 | rcu_read_unlock(); | |
ec09ebc1 | 427 | return retval < 0 ? retval : 0; |
e09eff7f | 428 | } |
9a393b5d | 429 | EXPORT_SYMBOL_GPL(tap_get_minor); |
e09eff7f | 430 | |
d9f1f61c | 431 | void tap_free_minor(dev_t major, struct tap_dev *tap) |
e09eff7f | 432 | { |
d9f1f61c SG |
433 | struct major_info *tap_major; |
434 | ||
435 | rcu_read_lock(); | |
436 | tap_major = tap_get_major(MAJOR(major)); | |
437 | if (!tap_major) { | |
438 | goto unlock; | |
439 | } | |
440 | ||
ffa423fb | 441 | spin_lock(&tap_major->minor_lock); |
6fe3faf8 | 442 | if (tap->minor) { |
d9f1f61c | 443 | idr_remove(&tap_major->minor_idr, tap->minor); |
6fe3faf8 | 444 | tap->minor = 0; |
e09eff7f | 445 | } |
ffa423fb | 446 | spin_unlock(&tap_major->minor_lock); |
d9f1f61c SG |
447 | |
448 | unlock: | |
449 | rcu_read_unlock(); | |
e09eff7f | 450 | } |
9a393b5d | 451 | EXPORT_SYMBOL_GPL(tap_free_minor); |
e09eff7f | 452 | |
d9f1f61c | 453 | static struct tap_dev *dev_get_by_tap_file(int major, int minor) |
e09eff7f EB |
454 | { |
455 | struct net_device *dev = NULL; | |
6fe3faf8 | 456 | struct tap_dev *tap; |
d9f1f61c | 457 | struct major_info *tap_major; |
e09eff7f | 458 | |
d9f1f61c SG |
459 | rcu_read_lock(); |
460 | tap_major = tap_get_major(major); | |
461 | if (!tap_major) { | |
462 | tap = NULL; | |
463 | goto unlock; | |
464 | } | |
465 | ||
ffa423fb | 466 | spin_lock(&tap_major->minor_lock); |
d9f1f61c | 467 | tap = idr_find(&tap_major->minor_idr, minor); |
6fe3faf8 SG |
468 | if (tap) { |
469 | dev = tap->dev; | |
e09eff7f EB |
470 | dev_hold(dev); |
471 | } | |
ffa423fb | 472 | spin_unlock(&tap_major->minor_lock); |
d9f1f61c SG |
473 | |
474 | unlock: | |
475 | rcu_read_unlock(); | |
6fe3faf8 | 476 | return tap; |
e09eff7f EB |
477 | } |
478 | ||
635b8c8e | 479 | static void tap_sock_write_space(struct sock *sk) |
20d29d7a | 480 | { |
43815482 ED |
481 | wait_queue_head_t *wqueue; |
482 | ||
20d29d7a | 483 | if (!sock_writeable(sk) || |
9cd3e072 | 484 | !test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &sk->sk_socket->flags)) |
20d29d7a AB |
485 | return; |
486 | ||
43815482 ED |
487 | wqueue = sk_sleep(sk); |
488 | if (wqueue && waitqueue_active(wqueue)) | |
a9a08845 | 489 | wake_up_interruptible_poll(wqueue, EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND); |
20d29d7a AB |
490 | } |
491 | ||
635b8c8e | 492 | static void tap_sock_destruct(struct sock *sk) |
2259fef0 | 493 | { |
635b8c8e | 494 | struct tap_queue *q = container_of(sk, struct tap_queue, sk); |
362899b8 | 495 | |
5990a305 | 496 | ptr_ring_cleanup(&q->ring, __skb_array_destroy_skb); |
2259fef0 EB |
497 | } |
498 | ||
635b8c8e | 499 | static int tap_open(struct inode *inode, struct file *file) |
20d29d7a AB |
500 | { |
501 | struct net *net = current->nsproxy->net_ns; | |
6fe3faf8 | 502 | struct tap_dev *tap; |
635b8c8e | 503 | struct tap_queue *q; |
40b8fe45 | 504 | int err = -ENODEV; |
20d29d7a | 505 | |
40b8fe45 | 506 | rtnl_lock(); |
d9f1f61c | 507 | tap = dev_get_by_tap_file(imajor(inode), iminor(inode)); |
6fe3faf8 | 508 | if (!tap) |
362899b8 | 509 | goto err; |
20d29d7a | 510 | |
20d29d7a | 511 | err = -ENOMEM; |
635b8c8e SG |
512 | q = (struct tap_queue *)sk_alloc(net, AF_UNSPEC, GFP_KERNEL, |
513 | &tap_proto, 0); | |
20d29d7a | 514 | if (!q) |
362899b8 | 515 | goto err; |
5990a305 | 516 | if (ptr_ring_init(&q->ring, tap->dev->tx_queue_len, GFP_KERNEL)) { |
78e0ea67 GM |
517 | sk_free(&q->sk); |
518 | goto err; | |
519 | } | |
20d29d7a | 520 | |
333f7909 | 521 | init_waitqueue_head(&q->sock.wq.wait); |
20d29d7a AB |
522 | q->sock.type = SOCK_RAW; |
523 | q->sock.state = SS_CONNECTED; | |
501c774c | 524 | q->sock.file = file; |
635b8c8e | 525 | q->sock.ops = &tap_socket_ops; |
20d29d7a | 526 | sock_init_data(&q->sock, &q->sk); |
635b8c8e SG |
527 | q->sk.sk_write_space = tap_sock_write_space; |
528 | q->sk.sk_destruct = tap_sock_destruct; | |
b9fb9ee0 | 529 | q->flags = IFF_VNET_HDR | IFF_NO_PI | IFF_TAP; |
55afbd08 | 530 | q->vnet_hdr_sz = sizeof(struct virtio_net_hdr); |
20d29d7a | 531 | |
97bc3633 | 532 | /* |
635b8c8e | 533 | * so far only KVM virtio_net uses tap, enable zero copy between |
97bc3633 | 534 | * guest kernel and host kernel when lower device supports zerocopy |
047af9cf EB |
535 | * |
536 | * The macvlan supports zerocopy iff the lower device supports zero | |
537 | * copy so we don't have to look at the lower device directly. | |
97bc3633 | 538 | */ |
6fe3faf8 | 539 | if ((tap->dev->features & NETIF_F_HIGHDMA) && (tap->dev->features & NETIF_F_SG)) |
047af9cf | 540 | sock_set_flag(&q->sk, SOCK_ZEROCOPY); |
97bc3633 | 541 | |
6fe3faf8 | 542 | err = tap_set_queue(tap, file, q); |
78e0ea67 | 543 | if (err) { |
5990a305 | 544 | /* tap_sock_destruct() will take care of freeing ptr_ring */ |
78e0ea67 GM |
545 | goto err_put; |
546 | } | |
20d29d7a | 547 | |
6fe3faf8 | 548 | dev_put(tap->dev); |
362899b8 JW |
549 | |
550 | rtnl_unlock(); | |
551 | return err; | |
552 | ||
78e0ea67 | 553 | err_put: |
362899b8 JW |
554 | sock_put(&q->sk); |
555 | err: | |
6fe3faf8 SG |
556 | if (tap) |
557 | dev_put(tap->dev); | |
20d29d7a | 558 | |
40b8fe45 | 559 | rtnl_unlock(); |
20d29d7a AB |
560 | return err; |
561 | } | |
562 | ||
635b8c8e | 563 | static int tap_release(struct inode *inode, struct file *file) |
20d29d7a | 564 | { |
635b8c8e SG |
565 | struct tap_queue *q = file->private_data; |
566 | tap_put_queue(q); | |
20d29d7a AB |
567 | return 0; |
568 | } | |
569 | ||
afc9a42b | 570 | static __poll_t tap_poll(struct file *file, poll_table *wait) |
20d29d7a | 571 | { |
635b8c8e | 572 | struct tap_queue *q = file->private_data; |
a9a08845 | 573 | __poll_t mask = EPOLLERR; |
20d29d7a AB |
574 | |
575 | if (!q) | |
576 | goto out; | |
577 | ||
578 | mask = 0; | |
333f7909 | 579 | poll_wait(file, &q->sock.wq.wait, wait); |
20d29d7a | 580 | |
5990a305 | 581 | if (!ptr_ring_empty(&q->ring)) |
a9a08845 | 582 | mask |= EPOLLIN | EPOLLRDNORM; |
20d29d7a AB |
583 | |
584 | if (sock_writeable(&q->sk) || | |
9cd3e072 | 585 | (!test_and_set_bit(SOCKWQ_ASYNC_NOSPACE, &q->sock.flags) && |
20d29d7a | 586 | sock_writeable(&q->sk))) |
a9a08845 | 587 | mask |= EPOLLOUT | EPOLLWRNORM; |
20d29d7a AB |
588 | |
589 | out: | |
20d29d7a AB |
590 | return mask; |
591 | } | |
592 | ||
635b8c8e SG |
593 | static inline struct sk_buff *tap_alloc_skb(struct sock *sk, size_t prepad, |
594 | size_t len, size_t linear, | |
b9fb9ee0 AB |
595 | int noblock, int *err) |
596 | { | |
597 | struct sk_buff *skb; | |
598 | ||
599 | /* Under a page? Don't bother with paged skb. */ | |
600 | if (prepad + len < PAGE_SIZE || !linear) | |
601 | linear = len; | |
602 | ||
603 | skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock, | |
28d64271 | 604 | err, 0); |
b9fb9ee0 AB |
605 | if (!skb) |
606 | return NULL; | |
607 | ||
608 | skb_reserve(skb, prepad); | |
609 | skb_put(skb, linear); | |
610 | skb->data_len = len - linear; | |
611 | skb->len += len - linear; | |
612 | ||
613 | return skb; | |
614 | } | |
615 | ||
2f1d8b9e | 616 | /* Neighbour code has some assumptions on HH_DATA_MOD alignment */ |
635b8c8e | 617 | #define TAP_RESERVE HH_DATA_OFF(ETH_HLEN) |
2f1d8b9e | 618 | |
20d29d7a | 619 | /* Get packet from user space buffer */ |
fe8dd45b | 620 | static ssize_t tap_get_user(struct tap_queue *q, void *msg_control, |
635b8c8e | 621 | struct iov_iter *from, int noblock) |
20d29d7a | 622 | { |
635b8c8e | 623 | int good_linear = SKB_MAX_HEAD(TAP_RESERVE); |
20d29d7a | 624 | struct sk_buff *skb; |
6fe3faf8 | 625 | struct tap_dev *tap; |
f5ff53b4 | 626 | unsigned long total_len = iov_iter_count(from); |
97bc3633 | 627 | unsigned long len = total_len; |
20d29d7a | 628 | int err; |
b9fb9ee0 AB |
629 | struct virtio_net_hdr vnet_hdr = { 0 }; |
630 | int vnet_hdr_len = 0; | |
b92946e2 | 631 | int copylen = 0; |
c5c62f1b | 632 | int depth; |
97bc3633 | 633 | bool zerocopy = false; |
61d46bf9 | 634 | size_t linear; |
b9fb9ee0 AB |
635 | |
636 | if (q->flags & IFF_VNET_HDR) { | |
837585a5 | 637 | vnet_hdr_len = READ_ONCE(q->vnet_hdr_sz); |
b9fb9ee0 AB |
638 | |
639 | err = -EINVAL; | |
ce3c8692 | 640 | if (len < vnet_hdr_len) |
b9fb9ee0 | 641 | goto err; |
ce3c8692 | 642 | len -= vnet_hdr_len; |
b9fb9ee0 | 643 | |
f5ff53b4 | 644 | err = -EFAULT; |
cbbd26b8 | 645 | if (!copy_from_iter_full(&vnet_hdr, sizeof(vnet_hdr), from)) |
b9fb9ee0 | 646 | goto err; |
f5ff53b4 | 647 | iov_iter_advance(from, vnet_hdr_len - sizeof(vnet_hdr)); |
b9fb9ee0 | 648 | if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && |
635b8c8e SG |
649 | tap16_to_cpu(q, vnet_hdr.csum_start) + |
650 | tap16_to_cpu(q, vnet_hdr.csum_offset) + 2 > | |
651 | tap16_to_cpu(q, vnet_hdr.hdr_len)) | |
652 | vnet_hdr.hdr_len = cpu_to_tap16(q, | |
653 | tap16_to_cpu(q, vnet_hdr.csum_start) + | |
654 | tap16_to_cpu(q, vnet_hdr.csum_offset) + 2); | |
b9fb9ee0 | 655 | err = -EINVAL; |
635b8c8e | 656 | if (tap16_to_cpu(q, vnet_hdr.hdr_len) > len) |
b9fb9ee0 AB |
657 | goto err; |
658 | } | |
20d29d7a | 659 | |
b9fb9ee0 | 660 | err = -EINVAL; |
20d29d7a | 661 | if (unlikely(len < ETH_HLEN)) |
b9fb9ee0 | 662 | goto err; |
20d29d7a | 663 | |
fe8dd45b | 664 | if (msg_control && sock_flag(&q->sk, SOCK_ZEROCOPY)) { |
f5ff53b4 AV |
665 | struct iov_iter i; |
666 | ||
6ae7feb3 | 667 | copylen = vnet_hdr.hdr_len ? |
635b8c8e | 668 | tap16_to_cpu(q, vnet_hdr.hdr_len) : GOODCOPY_LEN; |
16a3fa28 JW |
669 | if (copylen > good_linear) |
670 | copylen = good_linear; | |
8e2ad411 WB |
671 | else if (copylen < ETH_HLEN) |
672 | copylen = ETH_HLEN; | |
61d46bf9 | 673 | linear = copylen; |
f5ff53b4 AV |
674 | i = *from; |
675 | iov_iter_advance(&i, copylen); | |
676 | if (iov_iter_npages(&i, INT_MAX) <= MAX_SKB_FRAGS) | |
ece793fc JW |
677 | zerocopy = true; |
678 | } | |
679 | ||
680 | if (!zerocopy) { | |
97bc3633 | 681 | copylen = len; |
635b8c8e | 682 | linear = tap16_to_cpu(q, vnet_hdr.hdr_len); |
8e2ad411 | 683 | if (linear > good_linear) |
16a3fa28 | 684 | linear = good_linear; |
8e2ad411 WB |
685 | else if (linear < ETH_HLEN) |
686 | linear = ETH_HLEN; | |
61d46bf9 | 687 | } |
97bc3633 | 688 | |
635b8c8e SG |
689 | skb = tap_alloc_skb(&q->sk, TAP_RESERVE, copylen, |
690 | linear, noblock, &err); | |
02df55d2 AB |
691 | if (!skb) |
692 | goto err; | |
20d29d7a | 693 | |
01d6657b | 694 | if (zerocopy) |
f5ff53b4 | 695 | err = zerocopy_sg_from_iter(skb, from); |
aa196eed | 696 | else |
f5ff53b4 | 697 | err = skb_copy_datagram_from_iter(skb, 0, from, len); |
ece793fc | 698 | |
02df55d2 | 699 | if (err) |
b9fb9ee0 | 700 | goto err_kfree; |
20d29d7a AB |
701 | |
702 | skb_set_network_header(skb, ETH_HLEN); | |
b9fb9ee0 AB |
703 | skb_reset_mac_header(skb); |
704 | skb->protocol = eth_hdr(skb)->h_proto; | |
705 | ||
706 | if (vnet_hdr_len) { | |
fd88d68b | 707 | err = virtio_net_hdr_to_skb(skb, &vnet_hdr, |
635b8c8e | 708 | tap_is_little_endian(q)); |
b9fb9ee0 AB |
709 | if (err) |
710 | goto err_kfree; | |
711 | } | |
712 | ||
d2aa125d | 713 | skb_probe_transport_header(skb); |
9b4d669b | 714 | |
c5c62f1b IV |
715 | /* Move network header to the right position for VLAN tagged packets */ |
716 | if ((skb->protocol == htons(ETH_P_8021Q) || | |
717 | skb->protocol == htons(ETH_P_8021AD)) && | |
718 | __vlan_get_protocol(skb, skb->protocol, &depth) != 0) | |
719 | skb_set_network_header(skb, depth); | |
720 | ||
ac4e4af1 | 721 | rcu_read_lock(); |
6fe3faf8 | 722 | tap = rcu_dereference(q->tap); |
97bc3633 | 723 | /* copy skb_ubuf_info for callback when skb has no error */ |
01d6657b | 724 | if (zerocopy) { |
fe8dd45b | 725 | skb_shinfo(skb)->destructor_arg = msg_control; |
01d6657b | 726 | skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY; |
c9af6db4 | 727 | skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG; |
fe8dd45b JW |
728 | } else if (msg_control) { |
729 | struct ubuf_info *uarg = msg_control; | |
aa196eed | 730 | uarg->callback(uarg, false); |
01d6657b | 731 | } |
aa196eed | 732 | |
6fe3faf8 SG |
733 | if (tap) { |
734 | skb->dev = tap->dev; | |
6acf54f1 | 735 | dev_queue_xmit(skb); |
29d79196 | 736 | } else { |
02df55d2 | 737 | kfree_skb(skb); |
29d79196 | 738 | } |
ac4e4af1 | 739 | rcu_read_unlock(); |
20d29d7a | 740 | |
97bc3633 | 741 | return total_len; |
02df55d2 | 742 | |
b9fb9ee0 AB |
743 | err_kfree: |
744 | kfree_skb(skb); | |
745 | ||
02df55d2 | 746 | err: |
ac4e4af1 | 747 | rcu_read_lock(); |
6fe3faf8 SG |
748 | tap = rcu_dereference(q->tap); |
749 | if (tap && tap->count_tx_dropped) | |
750 | tap->count_tx_dropped(tap); | |
ac4e4af1 | 751 | rcu_read_unlock(); |
02df55d2 | 752 | |
02df55d2 | 753 | return err; |
20d29d7a AB |
754 | } |
755 | ||
635b8c8e | 756 | static ssize_t tap_write_iter(struct kiocb *iocb, struct iov_iter *from) |
20d29d7a AB |
757 | { |
758 | struct file *file = iocb->ki_filp; | |
635b8c8e | 759 | struct tap_queue *q = file->private_data; |
20d29d7a | 760 | |
635b8c8e | 761 | return tap_get_user(q, NULL, from, file->f_flags & O_NONBLOCK); |
20d29d7a AB |
762 | } |
763 | ||
764 | /* Put packet to the user space buffer */ | |
635b8c8e SG |
765 | static ssize_t tap_put_user(struct tap_queue *q, |
766 | const struct sk_buff *skb, | |
767 | struct iov_iter *iter) | |
20d29d7a | 768 | { |
20d29d7a | 769 | int ret; |
b9fb9ee0 | 770 | int vnet_hdr_len = 0; |
f09e2249 | 771 | int vlan_offset = 0; |
6c36d2e2 | 772 | int total; |
b9fb9ee0 AB |
773 | |
774 | if (q->flags & IFF_VNET_HDR) { | |
fd3a8862 | 775 | int vlan_hlen = skb_vlan_tag_present(skb) ? VLAN_HLEN : 0; |
b9fb9ee0 | 776 | struct virtio_net_hdr vnet_hdr; |
fd3a8862 | 777 | |
837585a5 | 778 | vnet_hdr_len = READ_ONCE(q->vnet_hdr_sz); |
6c36d2e2 | 779 | if (iov_iter_count(iter) < vnet_hdr_len) |
b9fb9ee0 AB |
780 | return -EINVAL; |
781 | ||
3e9e40e7 | 782 | if (virtio_net_hdr_from_skb(skb, &vnet_hdr, |
fd3a8862 WB |
783 | tap_is_little_endian(q), true, |
784 | vlan_hlen)) | |
fd88d68b | 785 | BUG(); |
b9fb9ee0 | 786 | |
6c36d2e2 HX |
787 | if (copy_to_iter(&vnet_hdr, sizeof(vnet_hdr), iter) != |
788 | sizeof(vnet_hdr)) | |
b9fb9ee0 | 789 | return -EFAULT; |
7cc76f51 JW |
790 | |
791 | iov_iter_advance(iter, vnet_hdr_len - sizeof(vnet_hdr)); | |
b9fb9ee0 | 792 | } |
6c36d2e2 | 793 | total = vnet_hdr_len; |
ce232ce0 | 794 | total += skb->len; |
f09e2249 | 795 | |
df8a39de | 796 | if (skb_vlan_tag_present(skb)) { |
f09e2249 BG |
797 | struct { |
798 | __be16 h_vlan_proto; | |
799 | __be16 h_vlan_TCI; | |
800 | } veth; | |
0fbe0d47 | 801 | veth.h_vlan_proto = skb->vlan_proto; |
df8a39de | 802 | veth.h_vlan_TCI = htons(skb_vlan_tag_get(skb)); |
f09e2249 BG |
803 | |
804 | vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto); | |
ce232ce0 | 805 | total += VLAN_HLEN; |
f09e2249 | 806 | |
6c36d2e2 HX |
807 | ret = skb_copy_datagram_iter(skb, 0, iter, vlan_offset); |
808 | if (ret || !iov_iter_count(iter)) | |
f09e2249 BG |
809 | goto done; |
810 | ||
6c36d2e2 HX |
811 | ret = copy_to_iter(&veth, sizeof(veth), iter); |
812 | if (ret != sizeof(veth) || !iov_iter_count(iter)) | |
f09e2249 BG |
813 | goto done; |
814 | } | |
20d29d7a | 815 | |
6c36d2e2 HX |
816 | ret = skb_copy_datagram_iter(skb, vlan_offset, iter, |
817 | skb->len - vlan_offset); | |
20d29d7a | 818 | |
f09e2249 | 819 | done: |
ce232ce0 | 820 | return ret ? ret : total; |
20d29d7a AB |
821 | } |
822 | ||
635b8c8e SG |
823 | static ssize_t tap_do_read(struct tap_queue *q, |
824 | struct iov_iter *to, | |
3b4ba04a | 825 | int noblock, struct sk_buff *skb) |
20d29d7a | 826 | { |
ccf7e72b | 827 | DEFINE_WAIT(wait); |
501c774c | 828 | ssize_t ret = 0; |
20d29d7a | 829 | |
61d78537 | 830 | if (!iov_iter_count(to)) { |
144a6adf | 831 | kfree_skb(skb); |
3af0bfe5 | 832 | return 0; |
61d78537 | 833 | } |
3af0bfe5 | 834 | |
3b4ba04a JW |
835 | if (skb) |
836 | goto put; | |
837 | ||
3af0bfe5 | 838 | while (1) { |
89cee917 JW |
839 | if (!noblock) |
840 | prepare_to_wait(sk_sleep(&q->sk), &wait, | |
841 | TASK_INTERRUPTIBLE); | |
20d29d7a AB |
842 | |
843 | /* Read frames from the queue */ | |
5990a305 | 844 | skb = ptr_ring_consume(&q->ring); |
3af0bfe5 AV |
845 | if (skb) |
846 | break; | |
847 | if (noblock) { | |
848 | ret = -EAGAIN; | |
849 | break; | |
20d29d7a | 850 | } |
3af0bfe5 AV |
851 | if (signal_pending(current)) { |
852 | ret = -ERESTARTSYS; | |
853 | break; | |
854 | } | |
855 | /* Nothing to read, let's sleep */ | |
856 | schedule(); | |
857 | } | |
a499a2e9 VY |
858 | if (!noblock) |
859 | finish_wait(sk_sleep(&q->sk), &wait); | |
860 | ||
3b4ba04a | 861 | put: |
3af0bfe5 | 862 | if (skb) { |
635b8c8e | 863 | ret = tap_put_user(q, skb, to); |
f51a5e82 JW |
864 | if (unlikely(ret < 0)) |
865 | kfree_skb(skb); | |
866 | else | |
867 | consume_skb(skb); | |
20d29d7a | 868 | } |
501c774c AB |
869 | return ret; |
870 | } | |
871 | ||
635b8c8e | 872 | static ssize_t tap_read_iter(struct kiocb *iocb, struct iov_iter *to) |
501c774c AB |
873 | { |
874 | struct file *file = iocb->ki_filp; | |
635b8c8e | 875 | struct tap_queue *q = file->private_data; |
3af0bfe5 | 876 | ssize_t len = iov_iter_count(to), ret; |
20d29d7a | 877 | |
3b4ba04a | 878 | ret = tap_do_read(q, to, file->f_flags & O_NONBLOCK, NULL); |
ce232ce0 | 879 | ret = min_t(ssize_t, ret, len); |
e6ebc7f1 ZYW |
880 | if (ret > 0) |
881 | iocb->ki_pos = ret; | |
20d29d7a AB |
882 | return ret; |
883 | } | |
884 | ||
6fe3faf8 | 885 | static struct tap_dev *tap_get_tap_dev(struct tap_queue *q) |
8f475a31 | 886 | { |
6fe3faf8 | 887 | struct tap_dev *tap; |
8f475a31 | 888 | |
441ac0fc | 889 | ASSERT_RTNL(); |
6fe3faf8 SG |
890 | tap = rtnl_dereference(q->tap); |
891 | if (tap) | |
892 | dev_hold(tap->dev); | |
8f475a31 | 893 | |
6fe3faf8 | 894 | return tap; |
8f475a31 JW |
895 | } |
896 | ||
6fe3faf8 | 897 | static void tap_put_tap_dev(struct tap_dev *tap) |
8f475a31 | 898 | { |
6fe3faf8 | 899 | dev_put(tap->dev); |
8f475a31 JW |
900 | } |
901 | ||
635b8c8e | 902 | static int tap_ioctl_set_queue(struct file *file, unsigned int flags) |
815f236d | 903 | { |
635b8c8e | 904 | struct tap_queue *q = file->private_data; |
6fe3faf8 | 905 | struct tap_dev *tap; |
815f236d JW |
906 | int ret; |
907 | ||
6fe3faf8 SG |
908 | tap = tap_get_tap_dev(q); |
909 | if (!tap) | |
815f236d JW |
910 | return -EINVAL; |
911 | ||
912 | if (flags & IFF_ATTACH_QUEUE) | |
6fe3faf8 | 913 | ret = tap_enable_queue(tap, file, q); |
815f236d | 914 | else if (flags & IFF_DETACH_QUEUE) |
635b8c8e | 915 | ret = tap_disable_queue(q); |
f57855a5 JW |
916 | else |
917 | ret = -EINVAL; | |
815f236d | 918 | |
6fe3faf8 | 919 | tap_put_tap_dev(tap); |
815f236d JW |
920 | return ret; |
921 | } | |
922 | ||
635b8c8e | 923 | static int set_offload(struct tap_queue *q, unsigned long arg) |
2be5c767 | 924 | { |
6fe3faf8 | 925 | struct tap_dev *tap; |
2be5c767 VY |
926 | netdev_features_t features; |
927 | netdev_features_t feature_mask = 0; | |
928 | ||
6fe3faf8 SG |
929 | tap = rtnl_dereference(q->tap); |
930 | if (!tap) | |
2be5c767 VY |
931 | return -ENOLINK; |
932 | ||
6fe3faf8 | 933 | features = tap->dev->features; |
2be5c767 VY |
934 | |
935 | if (arg & TUN_F_CSUM) { | |
936 | feature_mask = NETIF_F_HW_CSUM; | |
937 | ||
938 | if (arg & (TUN_F_TSO4 | TUN_F_TSO6)) { | |
939 | if (arg & TUN_F_TSO_ECN) | |
940 | feature_mask |= NETIF_F_TSO_ECN; | |
941 | if (arg & TUN_F_TSO4) | |
942 | feature_mask |= NETIF_F_TSO; | |
943 | if (arg & TUN_F_TSO6) | |
944 | feature_mask |= NETIF_F_TSO6; | |
945 | } | |
2be5c767 VY |
946 | } |
947 | ||
948 | /* tun/tap driver inverts the usage for TSO offloads, where | |
949 | * setting the TSO bit means that the userspace wants to | |
950 | * accept TSO frames and turning it off means that user space | |
951 | * does not support TSO. | |
635b8c8e | 952 | * For tap, we have to invert it to mean the same thing. |
2be5c767 VY |
953 | * When user space turns off TSO, we turn off GSO/LRO so that |
954 | * user-space will not receive TSO frames. | |
955 | */ | |
d591a1f3 | 956 | if (feature_mask & (NETIF_F_TSO | NETIF_F_TSO6)) |
2be5c767 VY |
957 | features |= RX_OFFLOADS; |
958 | else | |
959 | features &= ~RX_OFFLOADS; | |
960 | ||
961 | /* tap_features are the same as features on tun/tap and | |
962 | * reflect user expectations. | |
963 | */ | |
6fe3faf8 SG |
964 | tap->tap_features = feature_mask; |
965 | if (tap->update_features) | |
966 | tap->update_features(tap, features); | |
2be5c767 VY |
967 | |
968 | return 0; | |
969 | } | |
970 | ||
20d29d7a AB |
971 | /* |
972 | * provide compatibility with generic tun/tap interface | |
973 | */ | |
635b8c8e SG |
974 | static long tap_ioctl(struct file *file, unsigned int cmd, |
975 | unsigned long arg) | |
20d29d7a | 976 | { |
635b8c8e | 977 | struct tap_queue *q = file->private_data; |
6fe3faf8 | 978 | struct tap_dev *tap; |
20d29d7a AB |
979 | void __user *argp = (void __user *)arg; |
980 | struct ifreq __user *ifr = argp; | |
981 | unsigned int __user *up = argp; | |
39ec7de7 | 982 | unsigned short u; |
55afbd08 | 983 | int __user *sp = argp; |
7f460d30 | 984 | struct sockaddr sa; |
55afbd08 | 985 | int s; |
02df55d2 | 986 | int ret; |
20d29d7a AB |
987 | |
988 | switch (cmd) { | |
989 | case TUNSETIFF: | |
990 | /* ignore the name, just look at flags */ | |
991 | if (get_user(u, &ifr->ifr_flags)) | |
992 | return -EFAULT; | |
b9fb9ee0 AB |
993 | |
994 | ret = 0; | |
635b8c8e | 995 | if ((u & ~TAP_IFFEATURES) != (IFF_NO_PI | IFF_TAP)) |
b9fb9ee0 AB |
996 | ret = -EINVAL; |
997 | else | |
635b8c8e | 998 | q->flags = (q->flags & ~TAP_IFFEATURES) | u; |
b9fb9ee0 AB |
999 | |
1000 | return ret; | |
20d29d7a AB |
1001 | |
1002 | case TUNGETIFF: | |
441ac0fc | 1003 | rtnl_lock(); |
6fe3faf8 SG |
1004 | tap = tap_get_tap_dev(q); |
1005 | if (!tap) { | |
441ac0fc | 1006 | rtnl_unlock(); |
20d29d7a | 1007 | return -ENOLINK; |
441ac0fc | 1008 | } |
20d29d7a | 1009 | |
02df55d2 | 1010 | ret = 0; |
39ec7de7 | 1011 | u = q->flags; |
6fe3faf8 | 1012 | if (copy_to_user(&ifr->ifr_name, tap->dev->name, IFNAMSIZ) || |
39ec7de7 | 1013 | put_user(u, &ifr->ifr_flags)) |
02df55d2 | 1014 | ret = -EFAULT; |
6fe3faf8 | 1015 | tap_put_tap_dev(tap); |
441ac0fc | 1016 | rtnl_unlock(); |
02df55d2 | 1017 | return ret; |
20d29d7a | 1018 | |
815f236d JW |
1019 | case TUNSETQUEUE: |
1020 | if (get_user(u, &ifr->ifr_flags)) | |
1021 | return -EFAULT; | |
441ac0fc | 1022 | rtnl_lock(); |
635b8c8e | 1023 | ret = tap_ioctl_set_queue(file, u); |
441ac0fc | 1024 | rtnl_unlock(); |
82a19eb8 | 1025 | return ret; |
815f236d | 1026 | |
20d29d7a | 1027 | case TUNGETFEATURES: |
635b8c8e | 1028 | if (put_user(IFF_TAP | IFF_NO_PI | TAP_IFFEATURES, up)) |
20d29d7a AB |
1029 | return -EFAULT; |
1030 | return 0; | |
1031 | ||
1032 | case TUNSETSNDBUF: | |
3ea79249 | 1033 | if (get_user(s, sp)) |
20d29d7a | 1034 | return -EFAULT; |
93161922 CG |
1035 | if (s <= 0) |
1036 | return -EINVAL; | |
20d29d7a | 1037 | |
3ea79249 | 1038 | q->sk.sk_sndbuf = s; |
20d29d7a AB |
1039 | return 0; |
1040 | ||
55afbd08 MT |
1041 | case TUNGETVNETHDRSZ: |
1042 | s = q->vnet_hdr_sz; | |
1043 | if (put_user(s, sp)) | |
1044 | return -EFAULT; | |
1045 | return 0; | |
1046 | ||
1047 | case TUNSETVNETHDRSZ: | |
1048 | if (get_user(s, sp)) | |
1049 | return -EFAULT; | |
1050 | if (s < (int)sizeof(struct virtio_net_hdr)) | |
1051 | return -EINVAL; | |
1052 | ||
1053 | q->vnet_hdr_sz = s; | |
1054 | return 0; | |
1055 | ||
01b07fb3 | 1056 | case TUNGETVNETLE: |
635b8c8e | 1057 | s = !!(q->flags & TAP_VNET_LE); |
01b07fb3 MT |
1058 | if (put_user(s, sp)) |
1059 | return -EFAULT; | |
1060 | return 0; | |
1061 | ||
1062 | case TUNSETVNETLE: | |
1063 | if (get_user(s, sp)) | |
1064 | return -EFAULT; | |
1065 | if (s) | |
635b8c8e | 1066 | q->flags |= TAP_VNET_LE; |
01b07fb3 | 1067 | else |
635b8c8e | 1068 | q->flags &= ~TAP_VNET_LE; |
01b07fb3 MT |
1069 | return 0; |
1070 | ||
8b8e658b | 1071 | case TUNGETVNETBE: |
635b8c8e | 1072 | return tap_get_vnet_be(q, sp); |
8b8e658b GK |
1073 | |
1074 | case TUNSETVNETBE: | |
635b8c8e | 1075 | return tap_set_vnet_be(q, sp); |
8b8e658b | 1076 | |
20d29d7a AB |
1077 | case TUNSETOFFLOAD: |
1078 | /* let the user check for future flags */ | |
1079 | if (arg & ~(TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6 | | |
0c19f846 | 1080 | TUN_F_TSO_ECN | TUN_F_UFO)) |
20d29d7a AB |
1081 | return -EINVAL; |
1082 | ||
2be5c767 VY |
1083 | rtnl_lock(); |
1084 | ret = set_offload(q, arg); | |
1085 | rtnl_unlock(); | |
1086 | return ret; | |
20d29d7a | 1087 | |
b5082083 JC |
1088 | case SIOCGIFHWADDR: |
1089 | rtnl_lock(); | |
6fe3faf8 SG |
1090 | tap = tap_get_tap_dev(q); |
1091 | if (!tap) { | |
b5082083 JC |
1092 | rtnl_unlock(); |
1093 | return -ENOLINK; | |
1094 | } | |
1095 | ret = 0; | |
6fe3faf8 SG |
1096 | u = tap->dev->type; |
1097 | if (copy_to_user(&ifr->ifr_name, tap->dev->name, IFNAMSIZ) || | |
1098 | copy_to_user(&ifr->ifr_hwaddr.sa_data, tap->dev->dev_addr, ETH_ALEN) || | |
b5082083 JC |
1099 | put_user(u, &ifr->ifr_hwaddr.sa_family)) |
1100 | ret = -EFAULT; | |
6fe3faf8 | 1101 | tap_put_tap_dev(tap); |
b5082083 JC |
1102 | rtnl_unlock(); |
1103 | return ret; | |
1104 | ||
1105 | case SIOCSIFHWADDR: | |
7f460d30 JC |
1106 | if (copy_from_user(&sa, &ifr->ifr_hwaddr, sizeof(sa))) |
1107 | return -EFAULT; | |
b5082083 | 1108 | rtnl_lock(); |
6fe3faf8 SG |
1109 | tap = tap_get_tap_dev(q); |
1110 | if (!tap) { | |
b5082083 JC |
1111 | rtnl_unlock(); |
1112 | return -ENOLINK; | |
1113 | } | |
3a37a963 | 1114 | ret = dev_set_mac_address(tap->dev, &sa, NULL); |
6fe3faf8 | 1115 | tap_put_tap_dev(tap); |
b5082083 JC |
1116 | rtnl_unlock(); |
1117 | return ret; | |
1118 | ||
20d29d7a AB |
1119 | default: |
1120 | return -EINVAL; | |
1121 | } | |
1122 | } | |
1123 | ||
d17eb73b | 1124 | static const struct file_operations tap_fops = { |
20d29d7a | 1125 | .owner = THIS_MODULE, |
635b8c8e SG |
1126 | .open = tap_open, |
1127 | .release = tap_release, | |
1128 | .read_iter = tap_read_iter, | |
1129 | .write_iter = tap_write_iter, | |
1130 | .poll = tap_poll, | |
20d29d7a | 1131 | .llseek = no_llseek, |
635b8c8e | 1132 | .unlocked_ioctl = tap_ioctl, |
407e9ef7 | 1133 | .compat_ioctl = compat_ptr_ioctl, |
20d29d7a AB |
1134 | }; |
1135 | ||
0efac277 JW |
1136 | static int tap_get_user_xdp(struct tap_queue *q, struct xdp_buff *xdp) |
1137 | { | |
1138 | struct tun_xdp_hdr *hdr = xdp->data_hard_start; | |
1139 | struct virtio_net_hdr *gso = &hdr->gso; | |
1140 | int buflen = hdr->buflen; | |
1141 | int vnet_hdr_len = 0; | |
1142 | struct tap_dev *tap; | |
1143 | struct sk_buff *skb; | |
1144 | int err, depth; | |
1145 | ||
1146 | if (q->flags & IFF_VNET_HDR) | |
1147 | vnet_hdr_len = READ_ONCE(q->vnet_hdr_sz); | |
1148 | ||
1149 | skb = build_skb(xdp->data_hard_start, buflen); | |
1150 | if (!skb) { | |
1151 | err = -ENOMEM; | |
1152 | goto err; | |
1153 | } | |
1154 | ||
1155 | skb_reserve(skb, xdp->data - xdp->data_hard_start); | |
1156 | skb_put(skb, xdp->data_end - xdp->data); | |
1157 | ||
1158 | skb_set_network_header(skb, ETH_HLEN); | |
1159 | skb_reset_mac_header(skb); | |
1160 | skb->protocol = eth_hdr(skb)->h_proto; | |
1161 | ||
1162 | if (vnet_hdr_len) { | |
1163 | err = virtio_net_hdr_to_skb(skb, gso, tap_is_little_endian(q)); | |
1164 | if (err) | |
1165 | goto err_kfree; | |
1166 | } | |
1167 | ||
0efac277 JW |
1168 | /* Move network header to the right position for VLAN tagged packets */ |
1169 | if ((skb->protocol == htons(ETH_P_8021Q) || | |
1170 | skb->protocol == htons(ETH_P_8021AD)) && | |
1171 | __vlan_get_protocol(skb, skb->protocol, &depth) != 0) | |
1172 | skb_set_network_header(skb, depth); | |
1173 | ||
1174 | rcu_read_lock(); | |
1175 | tap = rcu_dereference(q->tap); | |
1176 | if (tap) { | |
1177 | skb->dev = tap->dev; | |
d2aa125d | 1178 | skb_probe_transport_header(skb); |
0efac277 JW |
1179 | dev_queue_xmit(skb); |
1180 | } else { | |
1181 | kfree_skb(skb); | |
1182 | } | |
1183 | rcu_read_unlock(); | |
1184 | ||
1185 | return 0; | |
1186 | ||
1187 | err_kfree: | |
1188 | kfree_skb(skb); | |
1189 | err: | |
1190 | rcu_read_lock(); | |
faeacb6d | 1191 | tap = rcu_dereference(q->tap); |
0efac277 JW |
1192 | if (tap && tap->count_tx_dropped) |
1193 | tap->count_tx_dropped(tap); | |
1194 | rcu_read_unlock(); | |
1195 | return err; | |
1196 | } | |
1197 | ||
635b8c8e SG |
1198 | static int tap_sendmsg(struct socket *sock, struct msghdr *m, |
1199 | size_t total_len) | |
501c774c | 1200 | { |
635b8c8e | 1201 | struct tap_queue *q = container_of(sock, struct tap_queue, sock); |
fe8dd45b | 1202 | struct tun_msg_ctl *ctl = m->msg_control; |
0efac277 JW |
1203 | struct xdp_buff *xdp; |
1204 | int i; | |
fe8dd45b | 1205 | |
0efac277 JW |
1206 | if (ctl && (ctl->type == TUN_MSG_PTR)) { |
1207 | for (i = 0; i < ctl->num; i++) { | |
1208 | xdp = &((struct xdp_buff *)ctl->ptr)[i]; | |
1209 | tap_get_user_xdp(q, xdp); | |
1210 | } | |
1211 | return 0; | |
1212 | } | |
fe8dd45b JW |
1213 | |
1214 | return tap_get_user(q, ctl ? ctl->ptr : NULL, &m->msg_iter, | |
1215 | m->msg_flags & MSG_DONTWAIT); | |
501c774c AB |
1216 | } |
1217 | ||
635b8c8e SG |
1218 | static int tap_recvmsg(struct socket *sock, struct msghdr *m, |
1219 | size_t total_len, int flags) | |
501c774c | 1220 | { |
635b8c8e | 1221 | struct tap_queue *q = container_of(sock, struct tap_queue, sock); |
61d78537 | 1222 | struct sk_buff *skb = m->msg_control; |
501c774c | 1223 | int ret; |
61d78537 | 1224 | if (flags & ~(MSG_DONTWAIT|MSG_TRUNC)) { |
144a6adf | 1225 | kfree_skb(skb); |
501c774c | 1226 | return -EINVAL; |
61d78537 WX |
1227 | } |
1228 | ret = tap_do_read(q, &m->msg_iter, flags & MSG_DONTWAIT, skb); | |
de2aa476 DM |
1229 | if (ret > total_len) { |
1230 | m->msg_flags |= MSG_TRUNC; | |
1231 | ret = flags & MSG_TRUNC ? ret : total_len; | |
1232 | } | |
501c774c AB |
1233 | return ret; |
1234 | } | |
1235 | ||
635b8c8e | 1236 | static int tap_peek_len(struct socket *sock) |
362899b8 | 1237 | { |
635b8c8e | 1238 | struct tap_queue *q = container_of(sock, struct tap_queue, |
362899b8 | 1239 | sock); |
5990a305 | 1240 | return PTR_RING_PEEK_CALL(&q->ring, __skb_array_len_with_tag); |
362899b8 JW |
1241 | } |
1242 | ||
501c774c | 1243 | /* Ops structure to mimic raw sockets with tun */ |
635b8c8e SG |
1244 | static const struct proto_ops tap_socket_ops = { |
1245 | .sendmsg = tap_sendmsg, | |
1246 | .recvmsg = tap_recvmsg, | |
1247 | .peek_len = tap_peek_len, | |
501c774c AB |
1248 | }; |
1249 | ||
1250 | /* Get an underlying socket object from tun file. Returns error unless file is | |
1251 | * attached to a device. The returned object works like a packet socket, it | |
1252 | * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for | |
1253 | * holding a reference to the file for as long as the socket is in use. */ | |
635b8c8e | 1254 | struct socket *tap_get_socket(struct file *file) |
501c774c | 1255 | { |
635b8c8e SG |
1256 | struct tap_queue *q; |
1257 | if (file->f_op != &tap_fops) | |
501c774c AB |
1258 | return ERR_PTR(-EINVAL); |
1259 | q = file->private_data; | |
1260 | if (!q) | |
1261 | return ERR_PTR(-EBADFD); | |
1262 | return &q->sock; | |
1263 | } | |
635b8c8e | 1264 | EXPORT_SYMBOL_GPL(tap_get_socket); |
501c774c | 1265 | |
5990a305 | 1266 | struct ptr_ring *tap_get_ptr_ring(struct file *file) |
49f96fd0 JW |
1267 | { |
1268 | struct tap_queue *q; | |
1269 | ||
1270 | if (file->f_op != &tap_fops) | |
1271 | return ERR_PTR(-EINVAL); | |
1272 | q = file->private_data; | |
1273 | if (!q) | |
1274 | return ERR_PTR(-EBADFD); | |
5990a305 | 1275 | return &q->ring; |
49f96fd0 | 1276 | } |
5990a305 | 1277 | EXPORT_SYMBOL_GPL(tap_get_ptr_ring); |
49f96fd0 | 1278 | |
6fe3faf8 | 1279 | int tap_queue_resize(struct tap_dev *tap) |
362899b8 | 1280 | { |
6fe3faf8 | 1281 | struct net_device *dev = tap->dev; |
635b8c8e | 1282 | struct tap_queue *q; |
5990a305 | 1283 | struct ptr_ring **rings; |
6fe3faf8 | 1284 | int n = tap->numqueues; |
362899b8 JW |
1285 | int ret, i = 0; |
1286 | ||
5990a305 JW |
1287 | rings = kmalloc_array(n, sizeof(*rings), GFP_KERNEL); |
1288 | if (!rings) | |
362899b8 JW |
1289 | return -ENOMEM; |
1290 | ||
6fe3faf8 | 1291 | list_for_each_entry(q, &tap->queue_list, next) |
5990a305 | 1292 | rings[i++] = &q->ring; |
362899b8 | 1293 | |
5990a305 JW |
1294 | ret = ptr_ring_resize_multiple(rings, n, |
1295 | dev->tx_queue_len, GFP_KERNEL, | |
1296 | __skb_array_destroy_skb); | |
362899b8 | 1297 | |
5990a305 | 1298 | kfree(rings); |
362899b8 JW |
1299 | return ret; |
1300 | } | |
9a393b5d | 1301 | EXPORT_SYMBOL_GPL(tap_queue_resize); |
ebc05ba7 | 1302 | |
d9f1f61c SG |
1303 | static int tap_list_add(dev_t major, const char *device_name) |
1304 | { | |
1305 | struct major_info *tap_major; | |
1306 | ||
1307 | tap_major = kzalloc(sizeof(*tap_major), GFP_ATOMIC); | |
1308 | if (!tap_major) | |
1309 | return -ENOMEM; | |
1310 | ||
1311 | tap_major->major = MAJOR(major); | |
1312 | ||
1313 | idr_init(&tap_major->minor_idr); | |
ffa423fb | 1314 | spin_lock_init(&tap_major->minor_lock); |
d9f1f61c SG |
1315 | |
1316 | tap_major->device_name = device_name; | |
1317 | ||
1318 | list_add_tail_rcu(&tap_major->next, &major_list); | |
1319 | return 0; | |
1320 | } | |
1321 | ||
dea6e19f GM |
1322 | int tap_create_cdev(struct cdev *tap_cdev, dev_t *tap_major, |
1323 | const char *device_name, struct module *module) | |
ebc05ba7 SG |
1324 | { |
1325 | int err; | |
1326 | ||
1327 | err = alloc_chrdev_region(tap_major, 0, TAP_NUM_DEVS, device_name); | |
1328 | if (err) | |
1329 | goto out1; | |
1330 | ||
1331 | cdev_init(tap_cdev, &tap_fops); | |
dea6e19f | 1332 | tap_cdev->owner = module; |
ebc05ba7 SG |
1333 | err = cdev_add(tap_cdev, *tap_major, TAP_NUM_DEVS); |
1334 | if (err) | |
1335 | goto out2; | |
1336 | ||
d9f1f61c SG |
1337 | err = tap_list_add(*tap_major, device_name); |
1338 | if (err) | |
1339 | goto out3; | |
ebc05ba7 SG |
1340 | |
1341 | return 0; | |
1342 | ||
d9f1f61c SG |
1343 | out3: |
1344 | cdev_del(tap_cdev); | |
ebc05ba7 SG |
1345 | out2: |
1346 | unregister_chrdev_region(*tap_major, TAP_NUM_DEVS); | |
1347 | out1: | |
1348 | return err; | |
1349 | } | |
9a393b5d | 1350 | EXPORT_SYMBOL_GPL(tap_create_cdev); |
ebc05ba7 SG |
1351 | |
1352 | void tap_destroy_cdev(dev_t major, struct cdev *tap_cdev) | |
1353 | { | |
d9f1f61c SG |
1354 | struct major_info *tap_major, *tmp; |
1355 | ||
ebc05ba7 SG |
1356 | cdev_del(tap_cdev); |
1357 | unregister_chrdev_region(major, TAP_NUM_DEVS); | |
d9f1f61c SG |
1358 | list_for_each_entry_safe(tap_major, tmp, &major_list, next) { |
1359 | if (tap_major->major == MAJOR(major)) { | |
1360 | idr_destroy(&tap_major->minor_idr); | |
1361 | list_del_rcu(&tap_major->next); | |
1362 | kfree_rcu(tap_major, rcu); | |
1363 | } | |
1364 | } | |
ebc05ba7 | 1365 | } |
9a393b5d SG |
1366 | EXPORT_SYMBOL_GPL(tap_destroy_cdev); |
1367 | ||
1368 | MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>"); | |
1369 | MODULE_AUTHOR("Sainath Grandhi <sainath.grandhi@intel.com>"); | |
1370 | MODULE_LICENSE("GPL"); |