xref: /openbmc/linux/drivers/vhost/vsock.c (revision 1440a3a1)
1 /*
2  * vhost transport for vsock
3  *
4  * Copyright (C) 2013-2015 Red Hat, Inc.
5  * Author: Asias He <asias@redhat.com>
6  *         Stefan Hajnoczi <stefanha@redhat.com>
7  *
8  * This work is licensed under the terms of the GNU GPL, version 2.
9  */
10 #include <linux/miscdevice.h>
11 #include <linux/atomic.h>
12 #include <linux/module.h>
13 #include <linux/mutex.h>
14 #include <linux/vmalloc.h>
15 #include <net/sock.h>
16 #include <linux/virtio_vsock.h>
17 #include <linux/vhost.h>
18 
19 #include <net/af_vsock.h>
20 #include "vhost.h"
21 
22 #define VHOST_VSOCK_DEFAULT_HOST_CID	2
23 
24 enum {
25 	VHOST_VSOCK_FEATURES = VHOST_FEATURES,
26 };
27 
28 /* Used to track all the vhost_vsock instances on the system. */
29 static DEFINE_SPINLOCK(vhost_vsock_lock);
30 static LIST_HEAD(vhost_vsock_list);
31 
32 struct vhost_vsock {
33 	struct vhost_dev dev;
34 	struct vhost_virtqueue vqs[2];
35 
36 	/* Link to global vhost_vsock_list, protected by vhost_vsock_lock */
37 	struct list_head list;
38 
39 	struct vhost_work send_pkt_work;
40 	spinlock_t send_pkt_list_lock;
41 	struct list_head send_pkt_list;	/* host->guest pending packets */
42 
43 	atomic_t queued_replies;
44 
45 	u32 guest_cid;
46 };
47 
48 static u32 vhost_transport_get_local_cid(void)
49 {
50 	return VHOST_VSOCK_DEFAULT_HOST_CID;
51 }
52 
53 static struct vhost_vsock *vhost_vsock_get(u32 guest_cid)
54 {
55 	struct vhost_vsock *vsock;
56 
57 	spin_lock_bh(&vhost_vsock_lock);
58 	list_for_each_entry(vsock, &vhost_vsock_list, list) {
59 		u32 other_cid = vsock->guest_cid;
60 
61 		/* Skip instances that have no CID yet */
62 		if (other_cid == 0)
63 			continue;
64 
65 		if (other_cid == guest_cid) {
66 			spin_unlock_bh(&vhost_vsock_lock);
67 			return vsock;
68 		}
69 	}
70 	spin_unlock_bh(&vhost_vsock_lock);
71 
72 	return NULL;
73 }
74 
75 static void
76 vhost_transport_do_send_pkt(struct vhost_vsock *vsock,
77 			    struct vhost_virtqueue *vq)
78 {
79 	struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX];
80 	bool added = false;
81 	bool restart_tx = false;
82 
83 	mutex_lock(&vq->mutex);
84 
85 	if (!vq->private_data)
86 		goto out;
87 
88 	/* Avoid further vmexits, we're already processing the virtqueue */
89 	vhost_disable_notify(&vsock->dev, vq);
90 
91 	for (;;) {
92 		struct virtio_vsock_pkt *pkt;
93 		struct iov_iter iov_iter;
94 		unsigned out, in;
95 		size_t nbytes;
96 		size_t len;
97 		int head;
98 
99 		spin_lock_bh(&vsock->send_pkt_list_lock);
100 		if (list_empty(&vsock->send_pkt_list)) {
101 			spin_unlock_bh(&vsock->send_pkt_list_lock);
102 			vhost_enable_notify(&vsock->dev, vq);
103 			break;
104 		}
105 
106 		pkt = list_first_entry(&vsock->send_pkt_list,
107 				       struct virtio_vsock_pkt, list);
108 		list_del_init(&pkt->list);
109 		spin_unlock_bh(&vsock->send_pkt_list_lock);
110 
111 		head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov),
112 					 &out, &in, NULL, NULL);
113 		if (head < 0) {
114 			spin_lock_bh(&vsock->send_pkt_list_lock);
115 			list_add(&pkt->list, &vsock->send_pkt_list);
116 			spin_unlock_bh(&vsock->send_pkt_list_lock);
117 			break;
118 		}
119 
120 		if (head == vq->num) {
121 			spin_lock_bh(&vsock->send_pkt_list_lock);
122 			list_add(&pkt->list, &vsock->send_pkt_list);
123 			spin_unlock_bh(&vsock->send_pkt_list_lock);
124 
125 			/* We cannot finish yet if more buffers snuck in while
126 			 * re-enabling notify.
127 			 */
128 			if (unlikely(vhost_enable_notify(&vsock->dev, vq))) {
129 				vhost_disable_notify(&vsock->dev, vq);
130 				continue;
131 			}
132 			break;
133 		}
134 
135 		if (out) {
136 			virtio_transport_free_pkt(pkt);
137 			vq_err(vq, "Expected 0 output buffers, got %u\n", out);
138 			break;
139 		}
140 
141 		len = iov_length(&vq->iov[out], in);
142 		iov_iter_init(&iov_iter, READ, &vq->iov[out], in, len);
143 
144 		nbytes = copy_to_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter);
145 		if (nbytes != sizeof(pkt->hdr)) {
146 			virtio_transport_free_pkt(pkt);
147 			vq_err(vq, "Faulted on copying pkt hdr\n");
148 			break;
149 		}
150 
151 		nbytes = copy_to_iter(pkt->buf, pkt->len, &iov_iter);
152 		if (nbytes != pkt->len) {
153 			virtio_transport_free_pkt(pkt);
154 			vq_err(vq, "Faulted on copying pkt buf\n");
155 			break;
156 		}
157 
158 		vhost_add_used(vq, head, sizeof(pkt->hdr) + pkt->len);
159 		added = true;
160 
161 		if (pkt->reply) {
162 			int val;
163 
164 			val = atomic_dec_return(&vsock->queued_replies);
165 
166 			/* Do we have resources to resume tx processing? */
167 			if (val + 1 == tx_vq->num)
168 				restart_tx = true;
169 		}
170 
171 		virtio_transport_free_pkt(pkt);
172 	}
173 	if (added)
174 		vhost_signal(&vsock->dev, vq);
175 
176 out:
177 	mutex_unlock(&vq->mutex);
178 
179 	if (restart_tx)
180 		vhost_poll_queue(&tx_vq->poll);
181 }
182 
183 static void vhost_transport_send_pkt_work(struct vhost_work *work)
184 {
185 	struct vhost_virtqueue *vq;
186 	struct vhost_vsock *vsock;
187 
188 	vsock = container_of(work, struct vhost_vsock, send_pkt_work);
189 	vq = &vsock->vqs[VSOCK_VQ_RX];
190 
191 	vhost_transport_do_send_pkt(vsock, vq);
192 }
193 
194 static int
195 vhost_transport_send_pkt(struct virtio_vsock_pkt *pkt)
196 {
197 	struct vhost_vsock *vsock;
198 	int len = pkt->len;
199 
200 	/* Find the vhost_vsock according to guest context id  */
201 	vsock = vhost_vsock_get(le64_to_cpu(pkt->hdr.dst_cid));
202 	if (!vsock) {
203 		virtio_transport_free_pkt(pkt);
204 		return -ENODEV;
205 	}
206 
207 	if (pkt->reply)
208 		atomic_inc(&vsock->queued_replies);
209 
210 	spin_lock_bh(&vsock->send_pkt_list_lock);
211 	list_add_tail(&pkt->list, &vsock->send_pkt_list);
212 	spin_unlock_bh(&vsock->send_pkt_list_lock);
213 
214 	vhost_work_queue(&vsock->dev, &vsock->send_pkt_work);
215 	return len;
216 }
217 
218 static struct virtio_vsock_pkt *
219 vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq,
220 		      unsigned int out, unsigned int in)
221 {
222 	struct virtio_vsock_pkt *pkt;
223 	struct iov_iter iov_iter;
224 	size_t nbytes;
225 	size_t len;
226 
227 	if (in != 0) {
228 		vq_err(vq, "Expected 0 input buffers, got %u\n", in);
229 		return NULL;
230 	}
231 
232 	pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
233 	if (!pkt)
234 		return NULL;
235 
236 	len = iov_length(vq->iov, out);
237 	iov_iter_init(&iov_iter, WRITE, vq->iov, out, len);
238 
239 	nbytes = copy_from_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter);
240 	if (nbytes != sizeof(pkt->hdr)) {
241 		vq_err(vq, "Expected %zu bytes for pkt->hdr, got %zu bytes\n",
242 		       sizeof(pkt->hdr), nbytes);
243 		kfree(pkt);
244 		return NULL;
245 	}
246 
247 	if (le16_to_cpu(pkt->hdr.type) == VIRTIO_VSOCK_TYPE_STREAM)
248 		pkt->len = le32_to_cpu(pkt->hdr.len);
249 
250 	/* No payload */
251 	if (!pkt->len)
252 		return pkt;
253 
254 	/* The pkt is too big */
255 	if (pkt->len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE) {
256 		kfree(pkt);
257 		return NULL;
258 	}
259 
260 	pkt->buf = kmalloc(pkt->len, GFP_KERNEL);
261 	if (!pkt->buf) {
262 		kfree(pkt);
263 		return NULL;
264 	}
265 
266 	nbytes = copy_from_iter(pkt->buf, pkt->len, &iov_iter);
267 	if (nbytes != pkt->len) {
268 		vq_err(vq, "Expected %u byte payload, got %zu bytes\n",
269 		       pkt->len, nbytes);
270 		virtio_transport_free_pkt(pkt);
271 		return NULL;
272 	}
273 
274 	return pkt;
275 }
276 
277 /* Is there space left for replies to rx packets? */
278 static bool vhost_vsock_more_replies(struct vhost_vsock *vsock)
279 {
280 	struct vhost_virtqueue *vq = &vsock->vqs[VSOCK_VQ_TX];
281 	int val;
282 
283 	smp_rmb(); /* paired with atomic_inc() and atomic_dec_return() */
284 	val = atomic_read(&vsock->queued_replies);
285 
286 	return val < vq->num;
287 }
288 
289 static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
290 {
291 	struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
292 						  poll.work);
293 	struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock,
294 						 dev);
295 	struct virtio_vsock_pkt *pkt;
296 	int head;
297 	unsigned int out, in;
298 	bool added = false;
299 
300 	mutex_lock(&vq->mutex);
301 
302 	if (!vq->private_data)
303 		goto out;
304 
305 	vhost_disable_notify(&vsock->dev, vq);
306 	for (;;) {
307 		u32 len;
308 
309 		if (!vhost_vsock_more_replies(vsock)) {
310 			/* Stop tx until the device processes already
311 			 * pending replies.  Leave tx virtqueue
312 			 * callbacks disabled.
313 			 */
314 			goto no_more_replies;
315 		}
316 
317 		head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov),
318 					 &out, &in, NULL, NULL);
319 		if (head < 0)
320 			break;
321 
322 		if (head == vq->num) {
323 			if (unlikely(vhost_enable_notify(&vsock->dev, vq))) {
324 				vhost_disable_notify(&vsock->dev, vq);
325 				continue;
326 			}
327 			break;
328 		}
329 
330 		pkt = vhost_vsock_alloc_pkt(vq, out, in);
331 		if (!pkt) {
332 			vq_err(vq, "Faulted on pkt\n");
333 			continue;
334 		}
335 
336 		len = pkt->len;
337 
338 		/* Only accept correctly addressed packets */
339 		if (le64_to_cpu(pkt->hdr.src_cid) == vsock->guest_cid)
340 			virtio_transport_recv_pkt(pkt);
341 		else
342 			virtio_transport_free_pkt(pkt);
343 
344 		vhost_add_used(vq, head, sizeof(pkt->hdr) + len);
345 		added = true;
346 	}
347 
348 no_more_replies:
349 	if (added)
350 		vhost_signal(&vsock->dev, vq);
351 
352 out:
353 	mutex_unlock(&vq->mutex);
354 }
355 
356 static void vhost_vsock_handle_rx_kick(struct vhost_work *work)
357 {
358 	struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
359 						poll.work);
360 	struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock,
361 						 dev);
362 
363 	vhost_transport_do_send_pkt(vsock, vq);
364 }
365 
366 static int vhost_vsock_start(struct vhost_vsock *vsock)
367 {
368 	size_t i;
369 	int ret;
370 
371 	mutex_lock(&vsock->dev.mutex);
372 
373 	ret = vhost_dev_check_owner(&vsock->dev);
374 	if (ret)
375 		goto err;
376 
377 	for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
378 		struct vhost_virtqueue *vq = &vsock->vqs[i];
379 
380 		mutex_lock(&vq->mutex);
381 
382 		if (!vhost_vq_access_ok(vq)) {
383 			ret = -EFAULT;
384 			mutex_unlock(&vq->mutex);
385 			goto err_vq;
386 		}
387 
388 		if (!vq->private_data) {
389 			vq->private_data = vsock;
390 			vhost_vq_init_access(vq);
391 		}
392 
393 		mutex_unlock(&vq->mutex);
394 	}
395 
396 	mutex_unlock(&vsock->dev.mutex);
397 	return 0;
398 
399 err_vq:
400 	for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
401 		struct vhost_virtqueue *vq = &vsock->vqs[i];
402 
403 		mutex_lock(&vq->mutex);
404 		vq->private_data = NULL;
405 		mutex_unlock(&vq->mutex);
406 	}
407 err:
408 	mutex_unlock(&vsock->dev.mutex);
409 	return ret;
410 }
411 
412 static int vhost_vsock_stop(struct vhost_vsock *vsock)
413 {
414 	size_t i;
415 	int ret;
416 
417 	mutex_lock(&vsock->dev.mutex);
418 
419 	ret = vhost_dev_check_owner(&vsock->dev);
420 	if (ret)
421 		goto err;
422 
423 	for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
424 		struct vhost_virtqueue *vq = &vsock->vqs[i];
425 
426 		mutex_lock(&vq->mutex);
427 		vq->private_data = NULL;
428 		mutex_unlock(&vq->mutex);
429 	}
430 
431 err:
432 	mutex_unlock(&vsock->dev.mutex);
433 	return ret;
434 }
435 
436 static void vhost_vsock_free(struct vhost_vsock *vsock)
437 {
438 	kvfree(vsock);
439 }
440 
441 static int vhost_vsock_dev_open(struct inode *inode, struct file *file)
442 {
443 	struct vhost_virtqueue **vqs;
444 	struct vhost_vsock *vsock;
445 	int ret;
446 
447 	/* This struct is large and allocation could fail, fall back to vmalloc
448 	 * if there is no other way.
449 	 */
450 	vsock = kzalloc(sizeof(*vsock), GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
451 	if (!vsock) {
452 		vsock = vmalloc(sizeof(*vsock));
453 		if (!vsock)
454 			return -ENOMEM;
455 	}
456 
457 	vqs = kmalloc_array(ARRAY_SIZE(vsock->vqs), sizeof(*vqs), GFP_KERNEL);
458 	if (!vqs) {
459 		ret = -ENOMEM;
460 		goto out;
461 	}
462 
463 	atomic_set(&vsock->queued_replies, 0);
464 
465 	vqs[VSOCK_VQ_TX] = &vsock->vqs[VSOCK_VQ_TX];
466 	vqs[VSOCK_VQ_RX] = &vsock->vqs[VSOCK_VQ_RX];
467 	vsock->vqs[VSOCK_VQ_TX].handle_kick = vhost_vsock_handle_tx_kick;
468 	vsock->vqs[VSOCK_VQ_RX].handle_kick = vhost_vsock_handle_rx_kick;
469 
470 	vhost_dev_init(&vsock->dev, vqs, ARRAY_SIZE(vsock->vqs));
471 
472 	file->private_data = vsock;
473 	spin_lock_init(&vsock->send_pkt_list_lock);
474 	INIT_LIST_HEAD(&vsock->send_pkt_list);
475 	vhost_work_init(&vsock->send_pkt_work, vhost_transport_send_pkt_work);
476 
477 	spin_lock_bh(&vhost_vsock_lock);
478 	list_add_tail(&vsock->list, &vhost_vsock_list);
479 	spin_unlock_bh(&vhost_vsock_lock);
480 	return 0;
481 
482 out:
483 	vhost_vsock_free(vsock);
484 	return ret;
485 }
486 
487 static void vhost_vsock_flush(struct vhost_vsock *vsock)
488 {
489 	int i;
490 
491 	for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++)
492 		if (vsock->vqs[i].handle_kick)
493 			vhost_poll_flush(&vsock->vqs[i].poll);
494 	vhost_work_flush(&vsock->dev, &vsock->send_pkt_work);
495 }
496 
497 static void vhost_vsock_reset_orphans(struct sock *sk)
498 {
499 	struct vsock_sock *vsk = vsock_sk(sk);
500 
501 	/* vmci_transport.c doesn't take sk_lock here either.  At least we're
502 	 * under vsock_table_lock so the sock cannot disappear while we're
503 	 * executing.
504 	 */
505 
506 	if (!vhost_vsock_get(vsk->local_addr.svm_cid)) {
507 		sock_set_flag(sk, SOCK_DONE);
508 		vsk->peer_shutdown = SHUTDOWN_MASK;
509 		sk->sk_state = SS_UNCONNECTED;
510 		sk->sk_err = ECONNRESET;
511 		sk->sk_error_report(sk);
512 	}
513 }
514 
515 static int vhost_vsock_dev_release(struct inode *inode, struct file *file)
516 {
517 	struct vhost_vsock *vsock = file->private_data;
518 
519 	spin_lock_bh(&vhost_vsock_lock);
520 	list_del(&vsock->list);
521 	spin_unlock_bh(&vhost_vsock_lock);
522 
523 	/* Iterating over all connections for all CIDs to find orphans is
524 	 * inefficient.  Room for improvement here. */
525 	vsock_for_each_connected_socket(vhost_vsock_reset_orphans);
526 
527 	vhost_vsock_stop(vsock);
528 	vhost_vsock_flush(vsock);
529 	vhost_dev_stop(&vsock->dev);
530 
531 	spin_lock_bh(&vsock->send_pkt_list_lock);
532 	while (!list_empty(&vsock->send_pkt_list)) {
533 		struct virtio_vsock_pkt *pkt;
534 
535 		pkt = list_first_entry(&vsock->send_pkt_list,
536 				struct virtio_vsock_pkt, list);
537 		list_del_init(&pkt->list);
538 		virtio_transport_free_pkt(pkt);
539 	}
540 	spin_unlock_bh(&vsock->send_pkt_list_lock);
541 
542 	vhost_dev_cleanup(&vsock->dev, false);
543 	kfree(vsock->dev.vqs);
544 	vhost_vsock_free(vsock);
545 	return 0;
546 }
547 
548 static int vhost_vsock_set_cid(struct vhost_vsock *vsock, u64 guest_cid)
549 {
550 	struct vhost_vsock *other;
551 
552 	/* Refuse reserved CIDs */
553 	if (guest_cid <= VMADDR_CID_HOST ||
554 	    guest_cid == U32_MAX)
555 		return -EINVAL;
556 
557 	/* 64-bit CIDs are not yet supported */
558 	if (guest_cid > U32_MAX)
559 		return -EINVAL;
560 
561 	/* Refuse if CID is already in use */
562 	other = vhost_vsock_get(guest_cid);
563 	if (other && other != vsock)
564 		return -EADDRINUSE;
565 
566 	spin_lock_bh(&vhost_vsock_lock);
567 	vsock->guest_cid = guest_cid;
568 	spin_unlock_bh(&vhost_vsock_lock);
569 
570 	return 0;
571 }
572 
573 static int vhost_vsock_set_features(struct vhost_vsock *vsock, u64 features)
574 {
575 	struct vhost_virtqueue *vq;
576 	int i;
577 
578 	if (features & ~VHOST_VSOCK_FEATURES)
579 		return -EOPNOTSUPP;
580 
581 	mutex_lock(&vsock->dev.mutex);
582 	if ((features & (1 << VHOST_F_LOG_ALL)) &&
583 	    !vhost_log_access_ok(&vsock->dev)) {
584 		mutex_unlock(&vsock->dev.mutex);
585 		return -EFAULT;
586 	}
587 
588 	for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
589 		vq = &vsock->vqs[i];
590 		mutex_lock(&vq->mutex);
591 		vq->acked_features = features;
592 		mutex_unlock(&vq->mutex);
593 	}
594 	mutex_unlock(&vsock->dev.mutex);
595 	return 0;
596 }
597 
598 static long vhost_vsock_dev_ioctl(struct file *f, unsigned int ioctl,
599 				  unsigned long arg)
600 {
601 	struct vhost_vsock *vsock = f->private_data;
602 	void __user *argp = (void __user *)arg;
603 	u64 guest_cid;
604 	u64 features;
605 	int start;
606 	int r;
607 
608 	switch (ioctl) {
609 	case VHOST_VSOCK_SET_GUEST_CID:
610 		if (copy_from_user(&guest_cid, argp, sizeof(guest_cid)))
611 			return -EFAULT;
612 		return vhost_vsock_set_cid(vsock, guest_cid);
613 	case VHOST_VSOCK_SET_RUNNING:
614 		if (copy_from_user(&start, argp, sizeof(start)))
615 			return -EFAULT;
616 		if (start)
617 			return vhost_vsock_start(vsock);
618 		else
619 			return vhost_vsock_stop(vsock);
620 	case VHOST_GET_FEATURES:
621 		features = VHOST_VSOCK_FEATURES;
622 		if (copy_to_user(argp, &features, sizeof(features)))
623 			return -EFAULT;
624 		return 0;
625 	case VHOST_SET_FEATURES:
626 		if (copy_from_user(&features, argp, sizeof(features)))
627 			return -EFAULT;
628 		return vhost_vsock_set_features(vsock, features);
629 	default:
630 		mutex_lock(&vsock->dev.mutex);
631 		r = vhost_dev_ioctl(&vsock->dev, ioctl, argp);
632 		if (r == -ENOIOCTLCMD)
633 			r = vhost_vring_ioctl(&vsock->dev, ioctl, argp);
634 		else
635 			vhost_vsock_flush(vsock);
636 		mutex_unlock(&vsock->dev.mutex);
637 		return r;
638 	}
639 }
640 
641 static const struct file_operations vhost_vsock_fops = {
642 	.owner          = THIS_MODULE,
643 	.open           = vhost_vsock_dev_open,
644 	.release        = vhost_vsock_dev_release,
645 	.llseek		= noop_llseek,
646 	.unlocked_ioctl = vhost_vsock_dev_ioctl,
647 };
648 
649 static struct miscdevice vhost_vsock_misc = {
650 	.minor = MISC_DYNAMIC_MINOR,
651 	.name = "vhost-vsock",
652 	.fops = &vhost_vsock_fops,
653 };
654 
655 static struct virtio_transport vhost_transport = {
656 	.transport = {
657 		.get_local_cid            = vhost_transport_get_local_cid,
658 
659 		.init                     = virtio_transport_do_socket_init,
660 		.destruct                 = virtio_transport_destruct,
661 		.release                  = virtio_transport_release,
662 		.connect                  = virtio_transport_connect,
663 		.shutdown                 = virtio_transport_shutdown,
664 
665 		.dgram_enqueue            = virtio_transport_dgram_enqueue,
666 		.dgram_dequeue            = virtio_transport_dgram_dequeue,
667 		.dgram_bind               = virtio_transport_dgram_bind,
668 		.dgram_allow              = virtio_transport_dgram_allow,
669 
670 		.stream_enqueue           = virtio_transport_stream_enqueue,
671 		.stream_dequeue           = virtio_transport_stream_dequeue,
672 		.stream_has_data          = virtio_transport_stream_has_data,
673 		.stream_has_space         = virtio_transport_stream_has_space,
674 		.stream_rcvhiwat          = virtio_transport_stream_rcvhiwat,
675 		.stream_is_active         = virtio_transport_stream_is_active,
676 		.stream_allow             = virtio_transport_stream_allow,
677 
678 		.notify_poll_in           = virtio_transport_notify_poll_in,
679 		.notify_poll_out          = virtio_transport_notify_poll_out,
680 		.notify_recv_init         = virtio_transport_notify_recv_init,
681 		.notify_recv_pre_block    = virtio_transport_notify_recv_pre_block,
682 		.notify_recv_pre_dequeue  = virtio_transport_notify_recv_pre_dequeue,
683 		.notify_recv_post_dequeue = virtio_transport_notify_recv_post_dequeue,
684 		.notify_send_init         = virtio_transport_notify_send_init,
685 		.notify_send_pre_block    = virtio_transport_notify_send_pre_block,
686 		.notify_send_pre_enqueue  = virtio_transport_notify_send_pre_enqueue,
687 		.notify_send_post_enqueue = virtio_transport_notify_send_post_enqueue,
688 
689 		.set_buffer_size          = virtio_transport_set_buffer_size,
690 		.set_min_buffer_size      = virtio_transport_set_min_buffer_size,
691 		.set_max_buffer_size      = virtio_transport_set_max_buffer_size,
692 		.get_buffer_size          = virtio_transport_get_buffer_size,
693 		.get_min_buffer_size      = virtio_transport_get_min_buffer_size,
694 		.get_max_buffer_size      = virtio_transport_get_max_buffer_size,
695 	},
696 
697 	.send_pkt = vhost_transport_send_pkt,
698 };
699 
700 static int __init vhost_vsock_init(void)
701 {
702 	int ret;
703 
704 	ret = vsock_core_init(&vhost_transport.transport);
705 	if (ret < 0)
706 		return ret;
707 	return misc_register(&vhost_vsock_misc);
708 };
709 
710 static void __exit vhost_vsock_exit(void)
711 {
712 	misc_deregister(&vhost_vsock_misc);
713 	vsock_core_exit();
714 };
715 
716 module_init(vhost_vsock_init);
717 module_exit(vhost_vsock_exit);
718 MODULE_LICENSE("GPL v2");
719 MODULE_AUTHOR("Asias He");
720 MODULE_DESCRIPTION("vhost transport for vsock ");
721