drivers/vhost/vsock.c

   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         struct vhost_virtqueue *vq;
 199         int len = pkt->len;
 200
 201         /* Find the vhost_vsock according to guest context id  */
 202         vsock = vhost_vsock_get(le64_to_cpu(pkt->hdr.dst_cid));
 203         if (!vsock) {
 204                 virtio_transport_free_pkt(pkt);
 205                 return -ENODEV;
 206         }
 207
 208         vq = &vsock->vqs[VSOCK_VQ_RX];
 209
 210         if (pkt->reply)
 211                 atomic_inc(&vsock->queued_replies);
 212
 213         spin_lock_bh(&vsock->send_pkt_list_lock);
 214         list_add_tail(&pkt->list, &vsock->send_pkt_list);
 215         spin_unlock_bh(&vsock->send_pkt_list_lock);
 216
 217         vhost_work_queue(&vsock->dev, &vsock->send_pkt_work);
 218         return len;
 219 }
 220
 221 static int
 222 vhost_transport_cancel_pkt(struct vsock_sock *vsk)
 223 {
 224         struct vhost_vsock *vsock;
 225         struct virtio_vsock_pkt *pkt, *n;
 226         int cnt = 0;
 227         LIST_HEAD(freeme);
 228
 229         /* Find the vhost_vsock according to guest context id  */
 230         vsock = vhost_vsock_get(vsk->remote_addr.svm_cid);
 231         if (!vsock)
 232                 return -ENODEV;
 233
 234         spin_lock_bh(&vsock->send_pkt_list_lock);
 235         list_for_each_entry_safe(pkt, n, &vsock->send_pkt_list, list) {
 236                 if (pkt->vsk != vsk)
 237                         continue;
 238                 list_move(&pkt->list, &freeme);
 239         }
 240         spin_unlock_bh(&vsock->send_pkt_list_lock);
 241
 242         list_for_each_entry_safe(pkt, n, &freeme, list) {
 243                 if (pkt->reply)
 244                         cnt++;
 245                 list_del(&pkt->list);
 246                 virtio_transport_free_pkt(pkt);
 247         }
 248
 249         if (cnt) {
 250                 struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX];
 251                 int new_cnt;
 252
 253                 new_cnt = atomic_sub_return(cnt, &vsock->queued_replies);
 254                 if (new_cnt + cnt >= tx_vq->num && new_cnt < tx_vq->num)
 255                         vhost_poll_queue(&tx_vq->poll);
 256         }
 257
 258         return 0;
 259 }
 260
 261 static struct virtio_vsock_pkt *
 262 vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq,
 263                       unsigned int out, unsigned int in)
 264 {
 265         struct virtio_vsock_pkt *pkt;
 266         struct iov_iter iov_iter;
 267         size_t nbytes;
 268         size_t len;
 269
 270         if (in != 0) {
 271                 vq_err(vq, "Expected 0 input buffers, got %u\n", in);
 272                 return NULL;
 273         }
 274
 275         pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
 276         if (!pkt)
 277                 return NULL;
 278
 279         len = iov_length(vq->iov, out);
 280         iov_iter_init(&iov_iter, WRITE, vq->iov, out, len);
 281
 282         nbytes = copy_from_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter);
 283         if (nbytes != sizeof(pkt->hdr)) {
 284                 vq_err(vq, "Expected %zu bytes for pkt->hdr, got %zu bytes\n",
 285                        sizeof(pkt->hdr), nbytes);
 286                 kfree(pkt);
 287                 return NULL;
 288         }
 289
 290         if (le16_to_cpu(pkt->hdr.type) == VIRTIO_VSOCK_TYPE_STREAM)
 291                 pkt->len = le32_to_cpu(pkt->hdr.len);
 292
 293         /* No payload */
 294         if (!pkt->len)
 295                 return pkt;
 296
 297         /* The pkt is too big */
 298         if (pkt->len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE) {
 299                 kfree(pkt);
 300                 return NULL;
 301         }
 302
 303         pkt->buf = kmalloc(pkt->len, GFP_KERNEL);
 304         if (!pkt->buf) {
 305                 kfree(pkt);
 306                 return NULL;
 307         }
 308
 309         nbytes = copy_from_iter(pkt->buf, pkt->len, &iov_iter);
 310         if (nbytes != pkt->len) {
 311                 vq_err(vq, "Expected %u byte payload, got %zu bytes\n",
 312                        pkt->len, nbytes);
 313                 virtio_transport_free_pkt(pkt);
 314                 return NULL;
 315         }
 316
 317         return pkt;
 318 }
 319
 320 /* Is there space left for replies to rx packets? */
 321 static bool vhost_vsock_more_replies(struct vhost_vsock *vsock)
 322 {
 323         struct vhost_virtqueue *vq = &vsock->vqs[VSOCK_VQ_TX];
 324         int val;
 325
 326         smp_rmb(); /* paired with atomic_inc() and atomic_dec_return() */
 327         val = atomic_read(&vsock->queued_replies);
 328
 329         return val < vq->num;
 330 }
 331
 332 static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
 333 {
 334         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
 335                                                   poll.work);
 336         struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock,
 337                                                  dev);
 338         struct virtio_vsock_pkt *pkt;
 339         int head;
 340         unsigned int out, in;
 341         bool added = false;
 342
 343         mutex_lock(&vq->mutex);
 344
 345         if (!vq->private_data)
 346                 goto out;
 347
 348         vhost_disable_notify(&vsock->dev, vq);
 349         for (;;) {
 350                 u32 len;
 351
 352                 if (!vhost_vsock_more_replies(vsock)) {
 353                         /* Stop tx until the device processes already
 354                          * pending replies.  Leave tx virtqueue
 355                          * callbacks disabled.
 356                          */
 357                         goto no_more_replies;
 358                 }
 359
 360                 head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov),
 361                                          &out, &in, NULL, NULL);
 362                 if (head < 0)
 363                         break;
 364
 365                 if (head == vq->num) {
 366                         if (unlikely(vhost_enable_notify(&vsock->dev, vq))) {
 367                                 vhost_disable_notify(&vsock->dev, vq);
 368                                 continue;
 369                         }
 370                         break;
 371                 }
 372
 373                 pkt = vhost_vsock_alloc_pkt(vq, out, in);
 374                 if (!pkt) {
 375                         vq_err(vq, "Faulted on pkt\n");
 376                         continue;
 377                 }
 378
 379                 len = pkt->len;
 380
 381                 /* Only accept correctly addressed packets */
 382                 if (le64_to_cpu(pkt->hdr.src_cid) == vsock->guest_cid)
 383                         virtio_transport_recv_pkt(pkt);
 384                 else
 385                         virtio_transport_free_pkt(pkt);
 386
 387                 vhost_add_used(vq, head, sizeof(pkt->hdr) + len);
 388                 added = true;
 389         }
 390
 391 no_more_replies:
 392         if (added)
 393                 vhost_signal(&vsock->dev, vq);
 394
 395 out:
 396         mutex_unlock(&vq->mutex);
 397 }
 398
 399 static void vhost_vsock_handle_rx_kick(struct vhost_work *work)
 400 {
 401         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
 402                                                 poll.work);
 403         struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock,
 404                                                  dev);
 405
 406         vhost_transport_do_send_pkt(vsock, vq);
 407 }
 408
 409 static int vhost_vsock_start(struct vhost_vsock *vsock)
 410 {
 411         struct vhost_virtqueue *vq;
 412         size_t i;
 413         int ret;
 414
 415         mutex_lock(&vsock->dev.mutex);
 416
 417         ret = vhost_dev_check_owner(&vsock->dev);
 418         if (ret)
 419                 goto err;
 420
 421         for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
 422                 vq = &vsock->vqs[i];
 423
 424                 mutex_lock(&vq->mutex);
 425
 426                 if (!vhost_vq_access_ok(vq)) {
 427                         ret = -EFAULT;
 428                         goto err_vq;
 429                 }
 430
 431                 if (!vq->private_data) {
 432                         vq->private_data = vsock;
 433                         ret = vhost_vq_init_access(vq);
 434                         if (ret)
 435                                 goto err_vq;
 436                 }
 437
 438                 mutex_unlock(&vq->mutex);
 439         }
 440
 441         mutex_unlock(&vsock->dev.mutex);
 442         return 0;
 443
 444 err_vq:
 445         vq->private_data = NULL;
 446         mutex_unlock(&vq->mutex);
 447
 448         for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
 449                 vq = &vsock->vqs[i];
 450
 451                 mutex_lock(&vq->mutex);
 452                 vq->private_data = NULL;
 453                 mutex_unlock(&vq->mutex);
 454         }
 455 err:
 456         mutex_unlock(&vsock->dev.mutex);
 457         return ret;
 458 }
 459
 460 static int vhost_vsock_stop(struct vhost_vsock *vsock)
 461 {
 462         size_t i;
 463         int ret;
 464
 465         mutex_lock(&vsock->dev.mutex);
 466
 467         ret = vhost_dev_check_owner(&vsock->dev);
 468         if (ret)
 469                 goto err;
 470
 471         for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
 472                 struct vhost_virtqueue *vq = &vsock->vqs[i];
 473
 474                 mutex_lock(&vq->mutex);
 475                 vq->private_data = NULL;
 476                 mutex_unlock(&vq->mutex);
 477         }
 478
 479 err:
 480         mutex_unlock(&vsock->dev.mutex);
 481         return ret;
 482 }
 483
 484 static void vhost_vsock_free(struct vhost_vsock *vsock)
 485 {
 486         kvfree(vsock);
 487 }
 488
 489 static int vhost_vsock_dev_open(struct inode *inode, struct file *file)
 490 {
 491         struct vhost_virtqueue **vqs;
 492         struct vhost_vsock *vsock;
 493         int ret;
 494
 495         /* This struct is large and allocation could fail, fall back to vmalloc
 496          * if there is no other way.
 497          */
 498         vsock = kzalloc(sizeof(*vsock), GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
 499         if (!vsock) {
 500                 vsock = vmalloc(sizeof(*vsock));
 501                 if (!vsock)
 502                         return -ENOMEM;
 503         }
 504
 505         vqs = kmalloc_array(ARRAY_SIZE(vsock->vqs), sizeof(*vqs), GFP_KERNEL);
 506         if (!vqs) {
 507                 ret = -ENOMEM;
 508                 goto out;
 509         }
 510
 511         atomic_set(&vsock->queued_replies, 0);
 512
 513         vqs[VSOCK_VQ_TX] = &vsock->vqs[VSOCK_VQ_TX];
 514         vqs[VSOCK_VQ_RX] = &vsock->vqs[VSOCK_VQ_RX];
 515         vsock->vqs[VSOCK_VQ_TX].handle_kick = vhost_vsock_handle_tx_kick;
 516         vsock->vqs[VSOCK_VQ_RX].handle_kick = vhost_vsock_handle_rx_kick;
 517
 518         vhost_dev_init(&vsock->dev, vqs, ARRAY_SIZE(vsock->vqs));
 519
 520         file->private_data = vsock;
 521         spin_lock_init(&vsock->send_pkt_list_lock);
 522         INIT_LIST_HEAD(&vsock->send_pkt_list);
 523         vhost_work_init(&vsock->send_pkt_work, vhost_transport_send_pkt_work);
 524
 525         spin_lock_bh(&vhost_vsock_lock);
 526         list_add_tail(&vsock->list, &vhost_vsock_list);
 527         spin_unlock_bh(&vhost_vsock_lock);
 528         return 0;
 529
 530 out:
 531         vhost_vsock_free(vsock);
 532         return ret;
 533 }
 534
 535 static void vhost_vsock_flush(struct vhost_vsock *vsock)
 536 {
 537         int i;
 538
 539         for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++)
 540                 if (vsock->vqs[i].handle_kick)
 541                         vhost_poll_flush(&vsock->vqs[i].poll);
 542         vhost_work_flush(&vsock->dev, &vsock->send_pkt_work);
 543 }
 544
 545 static void vhost_vsock_reset_orphans(struct sock *sk)
 546 {
 547         struct vsock_sock *vsk = vsock_sk(sk);
 548
 549         /* vmci_transport.c doesn't take sk_lock here either.  At least we're
 550          * under vsock_table_lock so the sock cannot disappear while we're
 551          * executing.
 552          */
 553
 554         if (!vhost_vsock_get(vsk->remote_addr.svm_cid)) {
 555                 sock_set_flag(sk, SOCK_DONE);
 556                 vsk->peer_shutdown = SHUTDOWN_MASK;
 557                 sk->sk_state = SS_UNCONNECTED;
 558                 sk->sk_err = ECONNRESET;
 559                 sk->sk_error_report(sk);
 560         }
 561 }
 562
 563 static int vhost_vsock_dev_release(struct inode *inode, struct file *file)
 564 {
 565         struct vhost_vsock *vsock = file->private_data;
 566
 567         spin_lock_bh(&vhost_vsock_lock);
 568         list_del(&vsock->list);
 569         spin_unlock_bh(&vhost_vsock_lock);
 570
 571         /* Iterating over all connections for all CIDs to find orphans is
 572          * inefficient.  Room for improvement here. */
 573         vsock_for_each_connected_socket(vhost_vsock_reset_orphans);
 574
 575         vhost_vsock_stop(vsock);
 576         vhost_vsock_flush(vsock);
 577         vhost_dev_stop(&vsock->dev);
 578
 579         spin_lock_bh(&vsock->send_pkt_list_lock);
 580         while (!list_empty(&vsock->send_pkt_list)) {
 581                 struct virtio_vsock_pkt *pkt;
 582
 583                 pkt = list_first_entry(&vsock->send_pkt_list,
 584                                 struct virtio_vsock_pkt, list);
 585                 list_del_init(&pkt->list);
 586                 virtio_transport_free_pkt(pkt);
 587         }
 588         spin_unlock_bh(&vsock->send_pkt_list_lock);
 589
 590         vhost_dev_cleanup(&vsock->dev, false);
 591         kfree(vsock->dev.vqs);
 592         vhost_vsock_free(vsock);
 593         return 0;
 594 }
 595
 596 static int vhost_vsock_set_cid(struct vhost_vsock *vsock, u64 guest_cid)
 597 {
 598         struct vhost_vsock *other;
 599
 600         /* Refuse reserved CIDs */
 601         if (guest_cid <= VMADDR_CID_HOST ||
 602             guest_cid == U32_MAX)
 603                 return -EINVAL;
 604
 605         /* 64-bit CIDs are not yet supported */
 606         if (guest_cid > U32_MAX)
 607                 return -EINVAL;
 608
 609         /* Refuse if CID is already in use */
 610         other = vhost_vsock_get(guest_cid);
 611         if (other && other != vsock)
 612                 return -EADDRINUSE;
 613
 614         spin_lock_bh(&vhost_vsock_lock);
 615         vsock->guest_cid = guest_cid;
 616         spin_unlock_bh(&vhost_vsock_lock);
 617
 618         return 0;
 619 }
 620
 621 static int vhost_vsock_set_features(struct vhost_vsock *vsock, u64 features)
 622 {
 623         struct vhost_virtqueue *vq;
 624         int i;
 625
 626         if (features & ~VHOST_VSOCK_FEATURES)
 627                 return -EOPNOTSUPP;
 628
 629         mutex_lock(&vsock->dev.mutex);
 630         if ((features & (1 << VHOST_F_LOG_ALL)) &&
 631             !vhost_log_access_ok(&vsock->dev)) {
 632                 mutex_unlock(&vsock->dev.mutex);
 633                 return -EFAULT;
 634         }
 635
 636         for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
 637                 vq = &vsock->vqs[i];
 638                 mutex_lock(&vq->mutex);
 639                 vq->acked_features = features;
 640                 mutex_unlock(&vq->mutex);
 641         }
 642         mutex_unlock(&vsock->dev.mutex);
 643         return 0;
 644 }
 645
 646 static long vhost_vsock_dev_ioctl(struct file *f, unsigned int ioctl,
 647                                   unsigned long arg)
 648 {
 649         struct vhost_vsock *vsock = f->private_data;
 650         void __user *argp = (void __user *)arg;
 651         u64 guest_cid;
 652         u64 features;
 653         int start;
 654         int r;
 655
 656         switch (ioctl) {
 657         case VHOST_VSOCK_SET_GUEST_CID:
 658                 if (copy_from_user(&guest_cid, argp, sizeof(guest_cid)))
 659                         return -EFAULT;
 660                 return vhost_vsock_set_cid(vsock, guest_cid);
 661         case VHOST_VSOCK_SET_RUNNING:
 662                 if (copy_from_user(&start, argp, sizeof(start)))
 663                         return -EFAULT;
 664                 if (start)
 665                         return vhost_vsock_start(vsock);
 666                 else
 667                         return vhost_vsock_stop(vsock);
 668         case VHOST_GET_FEATURES:
 669                 features = VHOST_VSOCK_FEATURES;
 670                 if (copy_to_user(argp, &features, sizeof(features)))
 671                         return -EFAULT;
 672                 return 0;
 673         case VHOST_SET_FEATURES:
 674                 if (copy_from_user(&features, argp, sizeof(features)))
 675                         return -EFAULT;
 676                 return vhost_vsock_set_features(vsock, features);
 677         default:
 678                 mutex_lock(&vsock->dev.mutex);
 679                 r = vhost_dev_ioctl(&vsock->dev, ioctl, argp);
 680                 if (r == -ENOIOCTLCMD)
 681                         r = vhost_vring_ioctl(&vsock->dev, ioctl, argp);
 682                 else
 683                         vhost_vsock_flush(vsock);
 684                 mutex_unlock(&vsock->dev.mutex);
 685                 return r;
 686         }
 687 }
 688
 689 static const struct file_operations vhost_vsock_fops = {
 690         .owner          = THIS_MODULE,
 691         .open           = vhost_vsock_dev_open,
 692         .release        = vhost_vsock_dev_release,
 693         .llseek         = noop_llseek,
 694         .unlocked_ioctl = vhost_vsock_dev_ioctl,
 695 };
 696
 697 static struct miscdevice vhost_vsock_misc = {
 698         .minor = MISC_DYNAMIC_MINOR,
 699         .name = "vhost-vsock",
 700         .fops = &vhost_vsock_fops,
 701 };
 702
 703 static struct virtio_transport vhost_transport = {
 704         .transport = {
 705                 .get_local_cid            = vhost_transport_get_local_cid,
 706
 707                 .init                     = virtio_transport_do_socket_init,
 708                 .destruct                 = virtio_transport_destruct,
 709                 .release                  = virtio_transport_release,
 710                 .connect                  = virtio_transport_connect,
 711                 .shutdown                 = virtio_transport_shutdown,
 712                 .cancel_pkt               = vhost_transport_cancel_pkt,
 713
 714                 .dgram_enqueue            = virtio_transport_dgram_enqueue,
 715                 .dgram_dequeue            = virtio_transport_dgram_dequeue,
 716                 .dgram_bind               = virtio_transport_dgram_bind,
 717                 .dgram_allow              = virtio_transport_dgram_allow,
 718
 719                 .stream_enqueue           = virtio_transport_stream_enqueue,
 720                 .stream_dequeue           = virtio_transport_stream_dequeue,
 721                 .stream_has_data          = virtio_transport_stream_has_data,
 722                 .stream_has_space         = virtio_transport_stream_has_space,
 723                 .stream_rcvhiwat          = virtio_transport_stream_rcvhiwat,
 724                 .stream_is_active         = virtio_transport_stream_is_active,
 725                 .stream_allow             = virtio_transport_stream_allow,
 726
 727                 .notify_poll_in           = virtio_transport_notify_poll_in,
 728                 .notify_poll_out          = virtio_transport_notify_poll_out,
 729                 .notify_recv_init         = virtio_transport_notify_recv_init,
 730                 .notify_recv_pre_block    = virtio_transport_notify_recv_pre_block,
 731                 .notify_recv_pre_dequeue  = virtio_transport_notify_recv_pre_dequeue,
 732                 .notify_recv_post_dequeue = virtio_transport_notify_recv_post_dequeue,
 733                 .notify_send_init         = virtio_transport_notify_send_init,
 734                 .notify_send_pre_block    = virtio_transport_notify_send_pre_block,
 735                 .notify_send_pre_enqueue  = virtio_transport_notify_send_pre_enqueue,
 736                 .notify_send_post_enqueue = virtio_transport_notify_send_post_enqueue,
 737
 738                 .set_buffer_size          = virtio_transport_set_buffer_size,
 739                 .set_min_buffer_size      = virtio_transport_set_min_buffer_size,
 740                 .set_max_buffer_size      = virtio_transport_set_max_buffer_size,
 741                 .get_buffer_size          = virtio_transport_get_buffer_size,
 742                 .get_min_buffer_size      = virtio_transport_get_min_buffer_size,
 743                 .get_max_buffer_size      = virtio_transport_get_max_buffer_size,
 744         },
 745
 746         .send_pkt = vhost_transport_send_pkt,
 747 };
 748
 749 static int __init vhost_vsock_init(void)
 750 {
 751         int ret;
 752
 753         ret = vsock_core_init(&vhost_transport.transport);
 754         if (ret < 0)
 755                 return ret;
 756         return misc_register(&vhost_vsock_misc);
 757 };
 758
 759 static void __exit vhost_vsock_exit(void)
 760 {
 761         misc_deregister(&vhost_vsock_misc);
 762         vsock_core_exit();
 763 };
 764
 765 module_init(vhost_vsock_init);
 766 module_exit(vhost_vsock_exit);
 767 MODULE_LICENSE("GPL v2");
 768 MODULE_AUTHOR("Asias He");
 769 MODULE_DESCRIPTION("vhost transport for vsock ");