1 // SPDX-License-Identifier: GPL-2.0-only
3 * vhost transport for vsock
5 * Copyright (C) 2013-2015 Red Hat, Inc.
6 * Author: Asias He <asias@redhat.com>
7 * Stefan Hajnoczi <stefanha@redhat.com>
9 #include <linux/miscdevice.h>
10 #include <linux/atomic.h>
11 #include <linux/module.h>
12 #include <linux/mutex.h>
13 #include <linux/vmalloc.h>
15 #include <linux/virtio_vsock.h>
16 #include <linux/vhost.h>
17 #include <linux/hashtable.h>
19 #include <net/af_vsock.h>
22 #define VHOST_VSOCK_DEFAULT_HOST_CID 2
23 /* Max number of bytes transferred before requeueing the job.
24 * Using this limit prevents one virtqueue from starving others. */
25 #define VHOST_VSOCK_WEIGHT 0x80000
26 /* Max number of packets transferred before requeueing the job.
27 * Using this limit prevents one virtqueue from starving others with
30 #define VHOST_VSOCK_PKT_WEIGHT 256
33 VHOST_VSOCK_FEATURES = VHOST_FEATURES |
34 (1ULL << VIRTIO_F_ACCESS_PLATFORM) |
35 (1ULL << VIRTIO_VSOCK_F_SEQPACKET)
39 VHOST_VSOCK_BACKEND_FEATURES = (1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2)
42 /* Used to track all the vhost_vsock instances on the system. */
43 static DEFINE_MUTEX(vhost_vsock_mutex);
44 static DEFINE_READ_MOSTLY_HASHTABLE(vhost_vsock_hash, 8);
48 struct vhost_virtqueue vqs[2];
50 /* Link to global vhost_vsock_hash, writes use vhost_vsock_mutex */
51 struct hlist_node hash;
53 struct vhost_work send_pkt_work;
54 struct sk_buff_head send_pkt_queue; /* host->guest pending packets */
56 atomic_t queued_replies;
62 static u32 vhost_transport_get_local_cid(void)
64 return VHOST_VSOCK_DEFAULT_HOST_CID;
67 /* Callers that dereference the return value must hold vhost_vsock_mutex or the
70 static struct vhost_vsock *vhost_vsock_get(u32 guest_cid)
72 struct vhost_vsock *vsock;
74 hash_for_each_possible_rcu(vhost_vsock_hash, vsock, hash, guest_cid) {
75 u32 other_cid = vsock->guest_cid;
77 /* Skip instances that have no CID yet */
81 if (other_cid == guest_cid)
90 vhost_transport_do_send_pkt(struct vhost_vsock *vsock,
91 struct vhost_virtqueue *vq)
93 struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX];
94 int pkts = 0, total_len = 0;
96 bool restart_tx = false;
98 mutex_lock(&vq->mutex);
100 if (!vhost_vq_get_backend(vq))
103 if (!vq_meta_prefetch(vq))
106 /* Avoid further vmexits, we're already processing the virtqueue */
107 vhost_disable_notify(&vsock->dev, vq);
110 struct virtio_vsock_hdr *hdr;
111 size_t iov_len, payload_len;
112 struct iov_iter iov_iter;
113 u32 flags_to_restore = 0;
119 skb = virtio_vsock_skb_dequeue(&vsock->send_pkt_queue);
122 vhost_enable_notify(&vsock->dev, vq);
126 head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov),
127 &out, &in, NULL, NULL);
129 virtio_vsock_skb_queue_head(&vsock->send_pkt_queue, skb);
133 if (head == vq->num) {
134 virtio_vsock_skb_queue_head(&vsock->send_pkt_queue, skb);
135 /* We cannot finish yet if more buffers snuck in while
136 * re-enabling notify.
138 if (unlikely(vhost_enable_notify(&vsock->dev, vq))) {
139 vhost_disable_notify(&vsock->dev, vq);
147 vq_err(vq, "Expected 0 output buffers, got %u\n", out);
151 iov_len = iov_length(&vq->iov[out], in);
152 if (iov_len < sizeof(*hdr)) {
154 vq_err(vq, "Buffer len [%zu] too small\n", iov_len);
158 iov_iter_init(&iov_iter, ITER_DEST, &vq->iov[out], in, iov_len);
159 payload_len = skb->len;
160 hdr = virtio_vsock_hdr(skb);
162 /* If the packet is greater than the space available in the
163 * buffer, we split it using multiple buffers.
165 if (payload_len > iov_len - sizeof(*hdr)) {
166 payload_len = iov_len - sizeof(*hdr);
168 /* As we are copying pieces of large packet's buffer to
169 * small rx buffers, headers of packets in rx queue are
170 * created dynamically and are initialized with header
171 * of current packet(except length). But in case of
172 * SOCK_SEQPACKET, we also must clear message delimeter
173 * bit (VIRTIO_VSOCK_SEQ_EOM) and MSG_EOR bit
174 * (VIRTIO_VSOCK_SEQ_EOR) if set. Otherwise,
175 * there will be sequence of packets with these
176 * bits set. After initialized header will be copied to
177 * rx buffer, these required bits will be restored.
179 if (le32_to_cpu(hdr->flags) & VIRTIO_VSOCK_SEQ_EOM) {
180 hdr->flags &= ~cpu_to_le32(VIRTIO_VSOCK_SEQ_EOM);
181 flags_to_restore |= VIRTIO_VSOCK_SEQ_EOM;
183 if (le32_to_cpu(hdr->flags) & VIRTIO_VSOCK_SEQ_EOR) {
184 hdr->flags &= ~cpu_to_le32(VIRTIO_VSOCK_SEQ_EOR);
185 flags_to_restore |= VIRTIO_VSOCK_SEQ_EOR;
190 /* Set the correct length in the header */
191 hdr->len = cpu_to_le32(payload_len);
193 nbytes = copy_to_iter(hdr, sizeof(*hdr), &iov_iter);
194 if (nbytes != sizeof(*hdr)) {
196 vq_err(vq, "Faulted on copying pkt hdr\n");
200 nbytes = copy_to_iter(skb->data, payload_len, &iov_iter);
201 if (nbytes != payload_len) {
203 vq_err(vq, "Faulted on copying pkt buf\n");
207 /* Deliver to monitoring devices all packets that we
210 virtio_transport_deliver_tap_pkt(skb);
212 vhost_add_used(vq, head, sizeof(*hdr) + payload_len);
215 skb_pull(skb, payload_len);
216 total_len += payload_len;
218 /* If we didn't send all the payload we can requeue the packet
219 * to send it with the next available buffer.
222 hdr->flags |= cpu_to_le32(flags_to_restore);
224 /* We are queueing the same skb to handle
225 * the remaining bytes, and we want to deliver it
226 * to monitoring devices in the next iteration.
228 virtio_vsock_skb_clear_tap_delivered(skb);
229 virtio_vsock_skb_queue_head(&vsock->send_pkt_queue, skb);
231 if (virtio_vsock_skb_reply(skb)) {
234 val = atomic_dec_return(&vsock->queued_replies);
236 /* Do we have resources to resume tx
239 if (val + 1 == tx_vq->num)
245 } while(likely(!vhost_exceeds_weight(vq, ++pkts, total_len)));
247 vhost_signal(&vsock->dev, vq);
250 mutex_unlock(&vq->mutex);
253 vhost_poll_queue(&tx_vq->poll);
256 static void vhost_transport_send_pkt_work(struct vhost_work *work)
258 struct vhost_virtqueue *vq;
259 struct vhost_vsock *vsock;
261 vsock = container_of(work, struct vhost_vsock, send_pkt_work);
262 vq = &vsock->vqs[VSOCK_VQ_RX];
264 vhost_transport_do_send_pkt(vsock, vq);
268 vhost_transport_send_pkt(struct sk_buff *skb)
270 struct virtio_vsock_hdr *hdr = virtio_vsock_hdr(skb);
271 struct vhost_vsock *vsock;
276 /* Find the vhost_vsock according to guest context id */
277 vsock = vhost_vsock_get(le64_to_cpu(hdr->dst_cid));
284 if (virtio_vsock_skb_reply(skb))
285 atomic_inc(&vsock->queued_replies);
287 virtio_vsock_skb_queue_tail(&vsock->send_pkt_queue, skb);
288 vhost_work_queue(&vsock->dev, &vsock->send_pkt_work);
295 vhost_transport_cancel_pkt(struct vsock_sock *vsk)
297 struct vhost_vsock *vsock;
303 /* Find the vhost_vsock according to guest context id */
304 vsock = vhost_vsock_get(vsk->remote_addr.svm_cid);
308 cnt = virtio_transport_purge_skbs(vsk, &vsock->send_pkt_queue);
311 struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX];
314 new_cnt = atomic_sub_return(cnt, &vsock->queued_replies);
315 if (new_cnt + cnt >= tx_vq->num && new_cnt < tx_vq->num)
316 vhost_poll_queue(&tx_vq->poll);
325 static struct sk_buff *
326 vhost_vsock_alloc_skb(struct vhost_virtqueue *vq,
327 unsigned int out, unsigned int in)
329 struct virtio_vsock_hdr *hdr;
330 struct iov_iter iov_iter;
337 vq_err(vq, "Expected 0 input buffers, got %u\n", in);
341 len = iov_length(vq->iov, out);
343 /* len contains both payload and hdr */
344 skb = virtio_vsock_alloc_skb(len, GFP_KERNEL);
348 iov_iter_init(&iov_iter, ITER_SOURCE, vq->iov, out, len);
350 hdr = virtio_vsock_hdr(skb);
351 nbytes = copy_from_iter(hdr, sizeof(*hdr), &iov_iter);
352 if (nbytes != sizeof(*hdr)) {
353 vq_err(vq, "Expected %zu bytes for pkt->hdr, got %zu bytes\n",
354 sizeof(*hdr), nbytes);
359 payload_len = le32_to_cpu(hdr->len);
365 /* The pkt is too big or the length in the header is invalid */
366 if (payload_len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE ||
367 payload_len + sizeof(*hdr) > len) {
372 virtio_vsock_skb_rx_put(skb);
374 nbytes = copy_from_iter(skb->data, payload_len, &iov_iter);
375 if (nbytes != payload_len) {
376 vq_err(vq, "Expected %zu byte payload, got %zu bytes\n",
377 payload_len, nbytes);
385 /* Is there space left for replies to rx packets? */
386 static bool vhost_vsock_more_replies(struct vhost_vsock *vsock)
388 struct vhost_virtqueue *vq = &vsock->vqs[VSOCK_VQ_TX];
391 smp_rmb(); /* paired with atomic_inc() and atomic_dec_return() */
392 val = atomic_read(&vsock->queued_replies);
394 return val < vq->num;
397 static bool vhost_transport_seqpacket_allow(u32 remote_cid);
399 static struct virtio_transport vhost_transport = {
401 .module = THIS_MODULE,
403 .get_local_cid = vhost_transport_get_local_cid,
405 .init = virtio_transport_do_socket_init,
406 .destruct = virtio_transport_destruct,
407 .release = virtio_transport_release,
408 .connect = virtio_transport_connect,
409 .shutdown = virtio_transport_shutdown,
410 .cancel_pkt = vhost_transport_cancel_pkt,
412 .dgram_enqueue = virtio_transport_dgram_enqueue,
413 .dgram_dequeue = virtio_transport_dgram_dequeue,
414 .dgram_bind = virtio_transport_dgram_bind,
415 .dgram_allow = virtio_transport_dgram_allow,
417 .stream_enqueue = virtio_transport_stream_enqueue,
418 .stream_dequeue = virtio_transport_stream_dequeue,
419 .stream_has_data = virtio_transport_stream_has_data,
420 .stream_has_space = virtio_transport_stream_has_space,
421 .stream_rcvhiwat = virtio_transport_stream_rcvhiwat,
422 .stream_is_active = virtio_transport_stream_is_active,
423 .stream_allow = virtio_transport_stream_allow,
425 .seqpacket_dequeue = virtio_transport_seqpacket_dequeue,
426 .seqpacket_enqueue = virtio_transport_seqpacket_enqueue,
427 .seqpacket_allow = vhost_transport_seqpacket_allow,
428 .seqpacket_has_data = virtio_transport_seqpacket_has_data,
430 .notify_poll_in = virtio_transport_notify_poll_in,
431 .notify_poll_out = virtio_transport_notify_poll_out,
432 .notify_recv_init = virtio_transport_notify_recv_init,
433 .notify_recv_pre_block = virtio_transport_notify_recv_pre_block,
434 .notify_recv_pre_dequeue = virtio_transport_notify_recv_pre_dequeue,
435 .notify_recv_post_dequeue = virtio_transport_notify_recv_post_dequeue,
436 .notify_send_init = virtio_transport_notify_send_init,
437 .notify_send_pre_block = virtio_transport_notify_send_pre_block,
438 .notify_send_pre_enqueue = virtio_transport_notify_send_pre_enqueue,
439 .notify_send_post_enqueue = virtio_transport_notify_send_post_enqueue,
440 .notify_buffer_size = virtio_transport_notify_buffer_size,
444 .send_pkt = vhost_transport_send_pkt,
447 static bool vhost_transport_seqpacket_allow(u32 remote_cid)
449 struct vhost_vsock *vsock;
450 bool seqpacket_allow = false;
453 vsock = vhost_vsock_get(remote_cid);
456 seqpacket_allow = vsock->seqpacket_allow;
460 return seqpacket_allow;
463 static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
465 struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
467 struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock,
469 int head, pkts = 0, total_len = 0;
470 unsigned int out, in;
474 mutex_lock(&vq->mutex);
476 if (!vhost_vq_get_backend(vq))
479 if (!vq_meta_prefetch(vq))
482 vhost_disable_notify(&vsock->dev, vq);
484 struct virtio_vsock_hdr *hdr;
486 if (!vhost_vsock_more_replies(vsock)) {
487 /* Stop tx until the device processes already
488 * pending replies. Leave tx virtqueue
489 * callbacks disabled.
491 goto no_more_replies;
494 head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov),
495 &out, &in, NULL, NULL);
499 if (head == vq->num) {
500 if (unlikely(vhost_enable_notify(&vsock->dev, vq))) {
501 vhost_disable_notify(&vsock->dev, vq);
507 skb = vhost_vsock_alloc_skb(vq, out, in);
509 vq_err(vq, "Faulted on pkt\n");
513 total_len += sizeof(*hdr) + skb->len;
515 /* Deliver to monitoring devices all received packets */
516 virtio_transport_deliver_tap_pkt(skb);
518 hdr = virtio_vsock_hdr(skb);
520 /* Only accept correctly addressed packets */
521 if (le64_to_cpu(hdr->src_cid) == vsock->guest_cid &&
522 le64_to_cpu(hdr->dst_cid) ==
523 vhost_transport_get_local_cid())
524 virtio_transport_recv_pkt(&vhost_transport, skb);
528 vhost_add_used(vq, head, 0);
530 } while(likely(!vhost_exceeds_weight(vq, ++pkts, total_len)));
534 vhost_signal(&vsock->dev, vq);
537 mutex_unlock(&vq->mutex);
540 static void vhost_vsock_handle_rx_kick(struct vhost_work *work)
542 struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
544 struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock,
547 vhost_transport_do_send_pkt(vsock, vq);
550 static int vhost_vsock_start(struct vhost_vsock *vsock)
552 struct vhost_virtqueue *vq;
556 mutex_lock(&vsock->dev.mutex);
558 ret = vhost_dev_check_owner(&vsock->dev);
562 for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
565 mutex_lock(&vq->mutex);
567 if (!vhost_vq_access_ok(vq)) {
572 if (!vhost_vq_get_backend(vq)) {
573 vhost_vq_set_backend(vq, vsock);
574 ret = vhost_vq_init_access(vq);
579 mutex_unlock(&vq->mutex);
582 /* Some packets may have been queued before the device was started,
583 * let's kick the send worker to send them.
585 vhost_work_queue(&vsock->dev, &vsock->send_pkt_work);
587 mutex_unlock(&vsock->dev.mutex);
591 vhost_vq_set_backend(vq, NULL);
592 mutex_unlock(&vq->mutex);
594 for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
597 mutex_lock(&vq->mutex);
598 vhost_vq_set_backend(vq, NULL);
599 mutex_unlock(&vq->mutex);
602 mutex_unlock(&vsock->dev.mutex);
606 static int vhost_vsock_stop(struct vhost_vsock *vsock, bool check_owner)
611 mutex_lock(&vsock->dev.mutex);
614 ret = vhost_dev_check_owner(&vsock->dev);
619 for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
620 struct vhost_virtqueue *vq = &vsock->vqs[i];
622 mutex_lock(&vq->mutex);
623 vhost_vq_set_backend(vq, NULL);
624 mutex_unlock(&vq->mutex);
628 mutex_unlock(&vsock->dev.mutex);
632 static void vhost_vsock_free(struct vhost_vsock *vsock)
637 static int vhost_vsock_dev_open(struct inode *inode, struct file *file)
639 struct vhost_virtqueue **vqs;
640 struct vhost_vsock *vsock;
643 /* This struct is large and allocation could fail, fall back to vmalloc
644 * if there is no other way.
646 vsock = kvmalloc(sizeof(*vsock), GFP_KERNEL | __GFP_RETRY_MAYFAIL);
650 vqs = kmalloc_array(ARRAY_SIZE(vsock->vqs), sizeof(*vqs), GFP_KERNEL);
656 vsock->guest_cid = 0; /* no CID assigned yet */
658 atomic_set(&vsock->queued_replies, 0);
660 vqs[VSOCK_VQ_TX] = &vsock->vqs[VSOCK_VQ_TX];
661 vqs[VSOCK_VQ_RX] = &vsock->vqs[VSOCK_VQ_RX];
662 vsock->vqs[VSOCK_VQ_TX].handle_kick = vhost_vsock_handle_tx_kick;
663 vsock->vqs[VSOCK_VQ_RX].handle_kick = vhost_vsock_handle_rx_kick;
665 vhost_dev_init(&vsock->dev, vqs, ARRAY_SIZE(vsock->vqs),
666 UIO_MAXIOV, VHOST_VSOCK_PKT_WEIGHT,
667 VHOST_VSOCK_WEIGHT, true, NULL);
669 file->private_data = vsock;
670 skb_queue_head_init(&vsock->send_pkt_queue);
671 vhost_work_init(&vsock->send_pkt_work, vhost_transport_send_pkt_work);
675 vhost_vsock_free(vsock);
679 static void vhost_vsock_flush(struct vhost_vsock *vsock)
681 vhost_dev_flush(&vsock->dev);
684 static void vhost_vsock_reset_orphans(struct sock *sk)
686 struct vsock_sock *vsk = vsock_sk(sk);
688 /* vmci_transport.c doesn't take sk_lock here either. At least we're
689 * under vsock_table_lock so the sock cannot disappear while we're
693 /* If the peer is still valid, no need to reset connection */
694 if (vhost_vsock_get(vsk->remote_addr.svm_cid))
697 /* If the close timeout is pending, let it expire. This avoids races
698 * with the timeout callback.
700 if (vsk->close_work_scheduled)
703 sock_set_flag(sk, SOCK_DONE);
704 vsk->peer_shutdown = SHUTDOWN_MASK;
705 sk->sk_state = SS_UNCONNECTED;
706 sk->sk_err = ECONNRESET;
710 static int vhost_vsock_dev_release(struct inode *inode, struct file *file)
712 struct vhost_vsock *vsock = file->private_data;
714 mutex_lock(&vhost_vsock_mutex);
715 if (vsock->guest_cid)
716 hash_del_rcu(&vsock->hash);
717 mutex_unlock(&vhost_vsock_mutex);
719 /* Wait for other CPUs to finish using vsock */
722 /* Iterating over all connections for all CIDs to find orphans is
723 * inefficient. Room for improvement here. */
724 vsock_for_each_connected_socket(&vhost_transport.transport,
725 vhost_vsock_reset_orphans);
727 /* Don't check the owner, because we are in the release path, so we
728 * need to stop the vsock device in any case.
729 * vhost_vsock_stop() can not fail in this case, so we don't need to
730 * check the return code.
732 vhost_vsock_stop(vsock, false);
733 vhost_vsock_flush(vsock);
734 vhost_dev_stop(&vsock->dev);
736 virtio_vsock_skb_queue_purge(&vsock->send_pkt_queue);
738 vhost_dev_cleanup(&vsock->dev);
739 kfree(vsock->dev.vqs);
740 vhost_vsock_free(vsock);
744 static int vhost_vsock_set_cid(struct vhost_vsock *vsock, u64 guest_cid)
746 struct vhost_vsock *other;
748 /* Refuse reserved CIDs */
749 if (guest_cid <= VMADDR_CID_HOST ||
750 guest_cid == U32_MAX)
753 /* 64-bit CIDs are not yet supported */
754 if (guest_cid > U32_MAX)
757 /* Refuse if CID is assigned to the guest->host transport (i.e. nested
758 * VM), to make the loopback work.
760 if (vsock_find_cid(guest_cid))
763 /* Refuse if CID is already in use */
764 mutex_lock(&vhost_vsock_mutex);
765 other = vhost_vsock_get(guest_cid);
766 if (other && other != vsock) {
767 mutex_unlock(&vhost_vsock_mutex);
771 if (vsock->guest_cid)
772 hash_del_rcu(&vsock->hash);
774 vsock->guest_cid = guest_cid;
775 hash_add_rcu(vhost_vsock_hash, &vsock->hash, vsock->guest_cid);
776 mutex_unlock(&vhost_vsock_mutex);
781 static int vhost_vsock_set_features(struct vhost_vsock *vsock, u64 features)
783 struct vhost_virtqueue *vq;
786 if (features & ~VHOST_VSOCK_FEATURES)
789 mutex_lock(&vsock->dev.mutex);
790 if ((features & (1 << VHOST_F_LOG_ALL)) &&
791 !vhost_log_access_ok(&vsock->dev)) {
795 if ((features & (1ULL << VIRTIO_F_ACCESS_PLATFORM))) {
796 if (vhost_init_device_iotlb(&vsock->dev))
800 if (features & (1ULL << VIRTIO_VSOCK_F_SEQPACKET))
801 vsock->seqpacket_allow = true;
803 for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
805 mutex_lock(&vq->mutex);
806 vq->acked_features = features;
807 mutex_unlock(&vq->mutex);
809 mutex_unlock(&vsock->dev.mutex);
813 mutex_unlock(&vsock->dev.mutex);
817 static long vhost_vsock_dev_ioctl(struct file *f, unsigned int ioctl,
820 struct vhost_vsock *vsock = f->private_data;
821 void __user *argp = (void __user *)arg;
828 case VHOST_VSOCK_SET_GUEST_CID:
829 if (copy_from_user(&guest_cid, argp, sizeof(guest_cid)))
831 return vhost_vsock_set_cid(vsock, guest_cid);
832 case VHOST_VSOCK_SET_RUNNING:
833 if (copy_from_user(&start, argp, sizeof(start)))
836 return vhost_vsock_start(vsock);
838 return vhost_vsock_stop(vsock, true);
839 case VHOST_GET_FEATURES:
840 features = VHOST_VSOCK_FEATURES;
841 if (copy_to_user(argp, &features, sizeof(features)))
844 case VHOST_SET_FEATURES:
845 if (copy_from_user(&features, argp, sizeof(features)))
847 return vhost_vsock_set_features(vsock, features);
848 case VHOST_GET_BACKEND_FEATURES:
849 features = VHOST_VSOCK_BACKEND_FEATURES;
850 if (copy_to_user(argp, &features, sizeof(features)))
853 case VHOST_SET_BACKEND_FEATURES:
854 if (copy_from_user(&features, argp, sizeof(features)))
856 if (features & ~VHOST_VSOCK_BACKEND_FEATURES)
858 vhost_set_backend_features(&vsock->dev, features);
861 mutex_lock(&vsock->dev.mutex);
862 r = vhost_dev_ioctl(&vsock->dev, ioctl, argp);
863 if (r == -ENOIOCTLCMD)
864 r = vhost_vring_ioctl(&vsock->dev, ioctl, argp);
866 vhost_vsock_flush(vsock);
867 mutex_unlock(&vsock->dev.mutex);
872 static ssize_t vhost_vsock_chr_read_iter(struct kiocb *iocb, struct iov_iter *to)
874 struct file *file = iocb->ki_filp;
875 struct vhost_vsock *vsock = file->private_data;
876 struct vhost_dev *dev = &vsock->dev;
877 int noblock = file->f_flags & O_NONBLOCK;
879 return vhost_chr_read_iter(dev, to, noblock);
882 static ssize_t vhost_vsock_chr_write_iter(struct kiocb *iocb,
883 struct iov_iter *from)
885 struct file *file = iocb->ki_filp;
886 struct vhost_vsock *vsock = file->private_data;
887 struct vhost_dev *dev = &vsock->dev;
889 return vhost_chr_write_iter(dev, from);
892 static __poll_t vhost_vsock_chr_poll(struct file *file, poll_table *wait)
894 struct vhost_vsock *vsock = file->private_data;
895 struct vhost_dev *dev = &vsock->dev;
897 return vhost_chr_poll(file, dev, wait);
900 static const struct file_operations vhost_vsock_fops = {
901 .owner = THIS_MODULE,
902 .open = vhost_vsock_dev_open,
903 .release = vhost_vsock_dev_release,
904 .llseek = noop_llseek,
905 .unlocked_ioctl = vhost_vsock_dev_ioctl,
906 .compat_ioctl = compat_ptr_ioctl,
907 .read_iter = vhost_vsock_chr_read_iter,
908 .write_iter = vhost_vsock_chr_write_iter,
909 .poll = vhost_vsock_chr_poll,
912 static struct miscdevice vhost_vsock_misc = {
913 .minor = VHOST_VSOCK_MINOR,
914 .name = "vhost-vsock",
915 .fops = &vhost_vsock_fops,
918 static int __init vhost_vsock_init(void)
922 ret = vsock_core_register(&vhost_transport.transport,
923 VSOCK_TRANSPORT_F_H2G);
927 ret = misc_register(&vhost_vsock_misc);
929 vsock_core_unregister(&vhost_transport.transport);
936 static void __exit vhost_vsock_exit(void)
938 misc_deregister(&vhost_vsock_misc);
939 vsock_core_unregister(&vhost_transport.transport);
942 module_init(vhost_vsock_init);
943 module_exit(vhost_vsock_exit);
944 MODULE_LICENSE("GPL v2");
945 MODULE_AUTHOR("Asias He");
946 MODULE_DESCRIPTION("vhost transport for vsock ");
947 MODULE_ALIAS_MISCDEV(VHOST_VSOCK_MINOR);
948 MODULE_ALIAS("devname:vhost-vsock");