1 /* 2 * virtio 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 * Some of the code is take from Gerd Hoffmann <kraxel@redhat.com>'s 9 * early virtio-vsock proof-of-concept bits. 10 * 11 * This work is licensed under the terms of the GNU GPL, version 2. 12 */ 13 #include <linux/spinlock.h> 14 #include <linux/module.h> 15 #include <linux/list.h> 16 #include <linux/atomic.h> 17 #include <linux/virtio.h> 18 #include <linux/virtio_ids.h> 19 #include <linux/virtio_config.h> 20 #include <linux/virtio_vsock.h> 21 #include <net/sock.h> 22 #include <linux/mutex.h> 23 #include <net/af_vsock.h> 24 25 static struct workqueue_struct *virtio_vsock_workqueue; 26 static struct virtio_vsock *the_virtio_vsock; 27 static DEFINE_MUTEX(the_virtio_vsock_mutex); /* protects the_virtio_vsock */ 28 29 struct virtio_vsock { 30 struct virtio_device *vdev; 31 struct virtqueue *vqs[VSOCK_VQ_MAX]; 32 33 /* Virtqueue processing is deferred to a workqueue */ 34 struct work_struct tx_work; 35 struct work_struct rx_work; 36 struct work_struct event_work; 37 38 /* The following fields are protected by tx_lock. vqs[VSOCK_VQ_TX] 39 * must be accessed with tx_lock held. 40 */ 41 struct mutex tx_lock; 42 43 struct work_struct send_pkt_work; 44 spinlock_t send_pkt_list_lock; 45 struct list_head send_pkt_list; 46 47 struct work_struct loopback_work; 48 spinlock_t loopback_list_lock; /* protects loopback_list */ 49 struct list_head loopback_list; 50 51 atomic_t queued_replies; 52 53 /* The following fields are protected by rx_lock. vqs[VSOCK_VQ_RX] 54 * must be accessed with rx_lock held. 55 */ 56 struct mutex rx_lock; 57 int rx_buf_nr; 58 int rx_buf_max_nr; 59 60 /* The following fields are protected by event_lock. 61 * vqs[VSOCK_VQ_EVENT] must be accessed with event_lock held. 62 */ 63 struct mutex event_lock; 64 struct virtio_vsock_event event_list[8]; 65 66 u32 guest_cid; 67 }; 68 69 static struct virtio_vsock *virtio_vsock_get(void) 70 { 71 return the_virtio_vsock; 72 } 73 74 static u32 virtio_transport_get_local_cid(void) 75 { 76 struct virtio_vsock *vsock = virtio_vsock_get(); 77 78 return vsock->guest_cid; 79 } 80 81 static void virtio_transport_loopback_work(struct work_struct *work) 82 { 83 struct virtio_vsock *vsock = 84 container_of(work, struct virtio_vsock, loopback_work); 85 LIST_HEAD(pkts); 86 87 spin_lock_bh(&vsock->loopback_list_lock); 88 list_splice_init(&vsock->loopback_list, &pkts); 89 spin_unlock_bh(&vsock->loopback_list_lock); 90 91 mutex_lock(&vsock->rx_lock); 92 while (!list_empty(&pkts)) { 93 struct virtio_vsock_pkt *pkt; 94 95 pkt = list_first_entry(&pkts, struct virtio_vsock_pkt, list); 96 list_del_init(&pkt->list); 97 98 virtio_transport_recv_pkt(pkt); 99 } 100 mutex_unlock(&vsock->rx_lock); 101 } 102 103 static int virtio_transport_send_pkt_loopback(struct virtio_vsock *vsock, 104 struct virtio_vsock_pkt *pkt) 105 { 106 int len = pkt->len; 107 108 spin_lock_bh(&vsock->loopback_list_lock); 109 list_add_tail(&pkt->list, &vsock->loopback_list); 110 spin_unlock_bh(&vsock->loopback_list_lock); 111 112 queue_work(virtio_vsock_workqueue, &vsock->loopback_work); 113 114 return len; 115 } 116 117 static void 118 virtio_transport_send_pkt_work(struct work_struct *work) 119 { 120 struct virtio_vsock *vsock = 121 container_of(work, struct virtio_vsock, send_pkt_work); 122 struct virtqueue *vq; 123 bool added = false; 124 bool restart_rx = false; 125 126 mutex_lock(&vsock->tx_lock); 127 128 vq = vsock->vqs[VSOCK_VQ_TX]; 129 130 for (;;) { 131 struct virtio_vsock_pkt *pkt; 132 struct scatterlist hdr, buf, *sgs[2]; 133 int ret, in_sg = 0, out_sg = 0; 134 bool reply; 135 136 spin_lock_bh(&vsock->send_pkt_list_lock); 137 if (list_empty(&vsock->send_pkt_list)) { 138 spin_unlock_bh(&vsock->send_pkt_list_lock); 139 break; 140 } 141 142 pkt = list_first_entry(&vsock->send_pkt_list, 143 struct virtio_vsock_pkt, list); 144 list_del_init(&pkt->list); 145 spin_unlock_bh(&vsock->send_pkt_list_lock); 146 147 reply = pkt->reply; 148 149 sg_init_one(&hdr, &pkt->hdr, sizeof(pkt->hdr)); 150 sgs[out_sg++] = &hdr; 151 if (pkt->buf) { 152 sg_init_one(&buf, pkt->buf, pkt->len); 153 sgs[out_sg++] = &buf; 154 } 155 156 ret = virtqueue_add_sgs(vq, sgs, out_sg, in_sg, pkt, GFP_KERNEL); 157 /* Usually this means that there is no more space available in 158 * the vq 159 */ 160 if (ret < 0) { 161 spin_lock_bh(&vsock->send_pkt_list_lock); 162 list_add(&pkt->list, &vsock->send_pkt_list); 163 spin_unlock_bh(&vsock->send_pkt_list_lock); 164 break; 165 } 166 167 if (reply) { 168 struct virtqueue *rx_vq = vsock->vqs[VSOCK_VQ_RX]; 169 int val; 170 171 val = atomic_dec_return(&vsock->queued_replies); 172 173 /* Do we now have resources to resume rx processing? */ 174 if (val + 1 == virtqueue_get_vring_size(rx_vq)) 175 restart_rx = true; 176 } 177 178 added = true; 179 } 180 181 if (added) 182 virtqueue_kick(vq); 183 184 mutex_unlock(&vsock->tx_lock); 185 186 if (restart_rx) 187 queue_work(virtio_vsock_workqueue, &vsock->rx_work); 188 } 189 190 static int 191 virtio_transport_send_pkt(struct virtio_vsock_pkt *pkt) 192 { 193 struct virtio_vsock *vsock; 194 int len = pkt->len; 195 196 vsock = virtio_vsock_get(); 197 if (!vsock) { 198 virtio_transport_free_pkt(pkt); 199 return -ENODEV; 200 } 201 202 if (le32_to_cpu(pkt->hdr.dst_cid) == vsock->guest_cid) 203 return virtio_transport_send_pkt_loopback(vsock, pkt); 204 205 if (pkt->reply) 206 atomic_inc(&vsock->queued_replies); 207 208 spin_lock_bh(&vsock->send_pkt_list_lock); 209 list_add_tail(&pkt->list, &vsock->send_pkt_list); 210 spin_unlock_bh(&vsock->send_pkt_list_lock); 211 212 queue_work(virtio_vsock_workqueue, &vsock->send_pkt_work); 213 return len; 214 } 215 216 static int 217 virtio_transport_cancel_pkt(struct vsock_sock *vsk) 218 { 219 struct virtio_vsock *vsock; 220 struct virtio_vsock_pkt *pkt, *n; 221 int cnt = 0; 222 LIST_HEAD(freeme); 223 224 vsock = virtio_vsock_get(); 225 if (!vsock) { 226 return -ENODEV; 227 } 228 229 spin_lock_bh(&vsock->send_pkt_list_lock); 230 list_for_each_entry_safe(pkt, n, &vsock->send_pkt_list, list) { 231 if (pkt->vsk != vsk) 232 continue; 233 list_move(&pkt->list, &freeme); 234 } 235 spin_unlock_bh(&vsock->send_pkt_list_lock); 236 237 list_for_each_entry_safe(pkt, n, &freeme, list) { 238 if (pkt->reply) 239 cnt++; 240 list_del(&pkt->list); 241 virtio_transport_free_pkt(pkt); 242 } 243 244 if (cnt) { 245 struct virtqueue *rx_vq = vsock->vqs[VSOCK_VQ_RX]; 246 int new_cnt; 247 248 new_cnt = atomic_sub_return(cnt, &vsock->queued_replies); 249 if (new_cnt + cnt >= virtqueue_get_vring_size(rx_vq) && 250 new_cnt < virtqueue_get_vring_size(rx_vq)) 251 queue_work(virtio_vsock_workqueue, &vsock->rx_work); 252 } 253 254 return 0; 255 } 256 257 static void virtio_vsock_rx_fill(struct virtio_vsock *vsock) 258 { 259 int buf_len = VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE; 260 struct virtio_vsock_pkt *pkt; 261 struct scatterlist hdr, buf, *sgs[2]; 262 struct virtqueue *vq; 263 int ret; 264 265 vq = vsock->vqs[VSOCK_VQ_RX]; 266 267 do { 268 pkt = kzalloc(sizeof(*pkt), GFP_KERNEL); 269 if (!pkt) 270 break; 271 272 pkt->buf = kmalloc(buf_len, GFP_KERNEL); 273 if (!pkt->buf) { 274 virtio_transport_free_pkt(pkt); 275 break; 276 } 277 278 pkt->len = buf_len; 279 280 sg_init_one(&hdr, &pkt->hdr, sizeof(pkt->hdr)); 281 sgs[0] = &hdr; 282 283 sg_init_one(&buf, pkt->buf, buf_len); 284 sgs[1] = &buf; 285 ret = virtqueue_add_sgs(vq, sgs, 0, 2, pkt, GFP_KERNEL); 286 if (ret) { 287 virtio_transport_free_pkt(pkt); 288 break; 289 } 290 vsock->rx_buf_nr++; 291 } while (vq->num_free); 292 if (vsock->rx_buf_nr > vsock->rx_buf_max_nr) 293 vsock->rx_buf_max_nr = vsock->rx_buf_nr; 294 virtqueue_kick(vq); 295 } 296 297 static void virtio_transport_tx_work(struct work_struct *work) 298 { 299 struct virtio_vsock *vsock = 300 container_of(work, struct virtio_vsock, tx_work); 301 struct virtqueue *vq; 302 bool added = false; 303 304 vq = vsock->vqs[VSOCK_VQ_TX]; 305 mutex_lock(&vsock->tx_lock); 306 do { 307 struct virtio_vsock_pkt *pkt; 308 unsigned int len; 309 310 virtqueue_disable_cb(vq); 311 while ((pkt = virtqueue_get_buf(vq, &len)) != NULL) { 312 virtio_transport_free_pkt(pkt); 313 added = true; 314 } 315 } while (!virtqueue_enable_cb(vq)); 316 mutex_unlock(&vsock->tx_lock); 317 318 if (added) 319 queue_work(virtio_vsock_workqueue, &vsock->send_pkt_work); 320 } 321 322 /* Is there space left for replies to rx packets? */ 323 static bool virtio_transport_more_replies(struct virtio_vsock *vsock) 324 { 325 struct virtqueue *vq = vsock->vqs[VSOCK_VQ_RX]; 326 int val; 327 328 smp_rmb(); /* paired with atomic_inc() and atomic_dec_return() */ 329 val = atomic_read(&vsock->queued_replies); 330 331 return val < virtqueue_get_vring_size(vq); 332 } 333 334 static void virtio_transport_rx_work(struct work_struct *work) 335 { 336 struct virtio_vsock *vsock = 337 container_of(work, struct virtio_vsock, rx_work); 338 struct virtqueue *vq; 339 340 vq = vsock->vqs[VSOCK_VQ_RX]; 341 342 mutex_lock(&vsock->rx_lock); 343 344 do { 345 virtqueue_disable_cb(vq); 346 for (;;) { 347 struct virtio_vsock_pkt *pkt; 348 unsigned int len; 349 350 if (!virtio_transport_more_replies(vsock)) { 351 /* Stop rx until the device processes already 352 * pending replies. Leave rx virtqueue 353 * callbacks disabled. 354 */ 355 goto out; 356 } 357 358 pkt = virtqueue_get_buf(vq, &len); 359 if (!pkt) { 360 break; 361 } 362 363 vsock->rx_buf_nr--; 364 365 /* Drop short/long packets */ 366 if (unlikely(len < sizeof(pkt->hdr) || 367 len > sizeof(pkt->hdr) + pkt->len)) { 368 virtio_transport_free_pkt(pkt); 369 continue; 370 } 371 372 pkt->len = len - sizeof(pkt->hdr); 373 virtio_transport_recv_pkt(pkt); 374 } 375 } while (!virtqueue_enable_cb(vq)); 376 377 out: 378 if (vsock->rx_buf_nr < vsock->rx_buf_max_nr / 2) 379 virtio_vsock_rx_fill(vsock); 380 mutex_unlock(&vsock->rx_lock); 381 } 382 383 /* event_lock must be held */ 384 static int virtio_vsock_event_fill_one(struct virtio_vsock *vsock, 385 struct virtio_vsock_event *event) 386 { 387 struct scatterlist sg; 388 struct virtqueue *vq; 389 390 vq = vsock->vqs[VSOCK_VQ_EVENT]; 391 392 sg_init_one(&sg, event, sizeof(*event)); 393 394 return virtqueue_add_inbuf(vq, &sg, 1, event, GFP_KERNEL); 395 } 396 397 /* event_lock must be held */ 398 static void virtio_vsock_event_fill(struct virtio_vsock *vsock) 399 { 400 size_t i; 401 402 for (i = 0; i < ARRAY_SIZE(vsock->event_list); i++) { 403 struct virtio_vsock_event *event = &vsock->event_list[i]; 404 405 virtio_vsock_event_fill_one(vsock, event); 406 } 407 408 virtqueue_kick(vsock->vqs[VSOCK_VQ_EVENT]); 409 } 410 411 static void virtio_vsock_reset_sock(struct sock *sk) 412 { 413 lock_sock(sk); 414 sk->sk_state = SS_UNCONNECTED; 415 sk->sk_err = ECONNRESET; 416 sk->sk_error_report(sk); 417 release_sock(sk); 418 } 419 420 static void virtio_vsock_update_guest_cid(struct virtio_vsock *vsock) 421 { 422 struct virtio_device *vdev = vsock->vdev; 423 __le64 guest_cid; 424 425 vdev->config->get(vdev, offsetof(struct virtio_vsock_config, guest_cid), 426 &guest_cid, sizeof(guest_cid)); 427 vsock->guest_cid = le64_to_cpu(guest_cid); 428 } 429 430 /* event_lock must be held */ 431 static void virtio_vsock_event_handle(struct virtio_vsock *vsock, 432 struct virtio_vsock_event *event) 433 { 434 switch (le32_to_cpu(event->id)) { 435 case VIRTIO_VSOCK_EVENT_TRANSPORT_RESET: 436 virtio_vsock_update_guest_cid(vsock); 437 vsock_for_each_connected_socket(virtio_vsock_reset_sock); 438 break; 439 } 440 } 441 442 static void virtio_transport_event_work(struct work_struct *work) 443 { 444 struct virtio_vsock *vsock = 445 container_of(work, struct virtio_vsock, event_work); 446 struct virtqueue *vq; 447 448 vq = vsock->vqs[VSOCK_VQ_EVENT]; 449 450 mutex_lock(&vsock->event_lock); 451 452 do { 453 struct virtio_vsock_event *event; 454 unsigned int len; 455 456 virtqueue_disable_cb(vq); 457 while ((event = virtqueue_get_buf(vq, &len)) != NULL) { 458 if (len == sizeof(*event)) 459 virtio_vsock_event_handle(vsock, event); 460 461 virtio_vsock_event_fill_one(vsock, event); 462 } 463 } while (!virtqueue_enable_cb(vq)); 464 465 virtqueue_kick(vsock->vqs[VSOCK_VQ_EVENT]); 466 467 mutex_unlock(&vsock->event_lock); 468 } 469 470 static void virtio_vsock_event_done(struct virtqueue *vq) 471 { 472 struct virtio_vsock *vsock = vq->vdev->priv; 473 474 if (!vsock) 475 return; 476 queue_work(virtio_vsock_workqueue, &vsock->event_work); 477 } 478 479 static void virtio_vsock_tx_done(struct virtqueue *vq) 480 { 481 struct virtio_vsock *vsock = vq->vdev->priv; 482 483 if (!vsock) 484 return; 485 queue_work(virtio_vsock_workqueue, &vsock->tx_work); 486 } 487 488 static void virtio_vsock_rx_done(struct virtqueue *vq) 489 { 490 struct virtio_vsock *vsock = vq->vdev->priv; 491 492 if (!vsock) 493 return; 494 queue_work(virtio_vsock_workqueue, &vsock->rx_work); 495 } 496 497 static struct virtio_transport virtio_transport = { 498 .transport = { 499 .get_local_cid = virtio_transport_get_local_cid, 500 501 .init = virtio_transport_do_socket_init, 502 .destruct = virtio_transport_destruct, 503 .release = virtio_transport_release, 504 .connect = virtio_transport_connect, 505 .shutdown = virtio_transport_shutdown, 506 .cancel_pkt = virtio_transport_cancel_pkt, 507 508 .dgram_bind = virtio_transport_dgram_bind, 509 .dgram_dequeue = virtio_transport_dgram_dequeue, 510 .dgram_enqueue = virtio_transport_dgram_enqueue, 511 .dgram_allow = virtio_transport_dgram_allow, 512 513 .stream_dequeue = virtio_transport_stream_dequeue, 514 .stream_enqueue = virtio_transport_stream_enqueue, 515 .stream_has_data = virtio_transport_stream_has_data, 516 .stream_has_space = virtio_transport_stream_has_space, 517 .stream_rcvhiwat = virtio_transport_stream_rcvhiwat, 518 .stream_is_active = virtio_transport_stream_is_active, 519 .stream_allow = virtio_transport_stream_allow, 520 521 .notify_poll_in = virtio_transport_notify_poll_in, 522 .notify_poll_out = virtio_transport_notify_poll_out, 523 .notify_recv_init = virtio_transport_notify_recv_init, 524 .notify_recv_pre_block = virtio_transport_notify_recv_pre_block, 525 .notify_recv_pre_dequeue = virtio_transport_notify_recv_pre_dequeue, 526 .notify_recv_post_dequeue = virtio_transport_notify_recv_post_dequeue, 527 .notify_send_init = virtio_transport_notify_send_init, 528 .notify_send_pre_block = virtio_transport_notify_send_pre_block, 529 .notify_send_pre_enqueue = virtio_transport_notify_send_pre_enqueue, 530 .notify_send_post_enqueue = virtio_transport_notify_send_post_enqueue, 531 532 .set_buffer_size = virtio_transport_set_buffer_size, 533 .set_min_buffer_size = virtio_transport_set_min_buffer_size, 534 .set_max_buffer_size = virtio_transport_set_max_buffer_size, 535 .get_buffer_size = virtio_transport_get_buffer_size, 536 .get_min_buffer_size = virtio_transport_get_min_buffer_size, 537 .get_max_buffer_size = virtio_transport_get_max_buffer_size, 538 }, 539 540 .send_pkt = virtio_transport_send_pkt, 541 }; 542 543 static int virtio_vsock_probe(struct virtio_device *vdev) 544 { 545 vq_callback_t *callbacks[] = { 546 virtio_vsock_rx_done, 547 virtio_vsock_tx_done, 548 virtio_vsock_event_done, 549 }; 550 static const char * const names[] = { 551 "rx", 552 "tx", 553 "event", 554 }; 555 struct virtio_vsock *vsock = NULL; 556 int ret; 557 558 ret = mutex_lock_interruptible(&the_virtio_vsock_mutex); 559 if (ret) 560 return ret; 561 562 /* Only one virtio-vsock device per guest is supported */ 563 if (the_virtio_vsock) { 564 ret = -EBUSY; 565 goto out; 566 } 567 568 vsock = kzalloc(sizeof(*vsock), GFP_KERNEL); 569 if (!vsock) { 570 ret = -ENOMEM; 571 goto out; 572 } 573 574 vsock->vdev = vdev; 575 576 ret = vsock->vdev->config->find_vqs(vsock->vdev, VSOCK_VQ_MAX, 577 vsock->vqs, callbacks, names, 578 NULL); 579 if (ret < 0) 580 goto out; 581 582 virtio_vsock_update_guest_cid(vsock); 583 584 ret = vsock_core_init(&virtio_transport.transport); 585 if (ret < 0) 586 goto out_vqs; 587 588 vsock->rx_buf_nr = 0; 589 vsock->rx_buf_max_nr = 0; 590 atomic_set(&vsock->queued_replies, 0); 591 592 vdev->priv = vsock; 593 the_virtio_vsock = vsock; 594 mutex_init(&vsock->tx_lock); 595 mutex_init(&vsock->rx_lock); 596 mutex_init(&vsock->event_lock); 597 spin_lock_init(&vsock->send_pkt_list_lock); 598 INIT_LIST_HEAD(&vsock->send_pkt_list); 599 spin_lock_init(&vsock->loopback_list_lock); 600 INIT_LIST_HEAD(&vsock->loopback_list); 601 INIT_WORK(&vsock->rx_work, virtio_transport_rx_work); 602 INIT_WORK(&vsock->tx_work, virtio_transport_tx_work); 603 INIT_WORK(&vsock->event_work, virtio_transport_event_work); 604 INIT_WORK(&vsock->send_pkt_work, virtio_transport_send_pkt_work); 605 INIT_WORK(&vsock->loopback_work, virtio_transport_loopback_work); 606 607 mutex_lock(&vsock->rx_lock); 608 virtio_vsock_rx_fill(vsock); 609 mutex_unlock(&vsock->rx_lock); 610 611 mutex_lock(&vsock->event_lock); 612 virtio_vsock_event_fill(vsock); 613 mutex_unlock(&vsock->event_lock); 614 615 mutex_unlock(&the_virtio_vsock_mutex); 616 return 0; 617 618 out_vqs: 619 vsock->vdev->config->del_vqs(vsock->vdev); 620 out: 621 kfree(vsock); 622 mutex_unlock(&the_virtio_vsock_mutex); 623 return ret; 624 } 625 626 static void virtio_vsock_remove(struct virtio_device *vdev) 627 { 628 struct virtio_vsock *vsock = vdev->priv; 629 struct virtio_vsock_pkt *pkt; 630 631 flush_work(&vsock->loopback_work); 632 flush_work(&vsock->rx_work); 633 flush_work(&vsock->tx_work); 634 flush_work(&vsock->event_work); 635 flush_work(&vsock->send_pkt_work); 636 637 vdev->config->reset(vdev); 638 639 mutex_lock(&vsock->rx_lock); 640 while ((pkt = virtqueue_detach_unused_buf(vsock->vqs[VSOCK_VQ_RX]))) 641 virtio_transport_free_pkt(pkt); 642 mutex_unlock(&vsock->rx_lock); 643 644 mutex_lock(&vsock->tx_lock); 645 while ((pkt = virtqueue_detach_unused_buf(vsock->vqs[VSOCK_VQ_TX]))) 646 virtio_transport_free_pkt(pkt); 647 mutex_unlock(&vsock->tx_lock); 648 649 spin_lock_bh(&vsock->send_pkt_list_lock); 650 while (!list_empty(&vsock->send_pkt_list)) { 651 pkt = list_first_entry(&vsock->send_pkt_list, 652 struct virtio_vsock_pkt, list); 653 list_del(&pkt->list); 654 virtio_transport_free_pkt(pkt); 655 } 656 spin_unlock_bh(&vsock->send_pkt_list_lock); 657 658 spin_lock_bh(&vsock->loopback_list_lock); 659 while (!list_empty(&vsock->loopback_list)) { 660 pkt = list_first_entry(&vsock->loopback_list, 661 struct virtio_vsock_pkt, list); 662 list_del(&pkt->list); 663 virtio_transport_free_pkt(pkt); 664 } 665 spin_unlock_bh(&vsock->loopback_list_lock); 666 667 mutex_lock(&the_virtio_vsock_mutex); 668 the_virtio_vsock = NULL; 669 vsock_core_exit(); 670 mutex_unlock(&the_virtio_vsock_mutex); 671 672 vdev->config->del_vqs(vdev); 673 674 kfree(vsock); 675 } 676 677 static struct virtio_device_id id_table[] = { 678 { VIRTIO_ID_VSOCK, VIRTIO_DEV_ANY_ID }, 679 { 0 }, 680 }; 681 682 static unsigned int features[] = { 683 }; 684 685 static struct virtio_driver virtio_vsock_driver = { 686 .feature_table = features, 687 .feature_table_size = ARRAY_SIZE(features), 688 .driver.name = KBUILD_MODNAME, 689 .driver.owner = THIS_MODULE, 690 .id_table = id_table, 691 .probe = virtio_vsock_probe, 692 .remove = virtio_vsock_remove, 693 }; 694 695 static int __init virtio_vsock_init(void) 696 { 697 int ret; 698 699 virtio_vsock_workqueue = alloc_workqueue("virtio_vsock", 0, 0); 700 if (!virtio_vsock_workqueue) 701 return -ENOMEM; 702 ret = register_virtio_driver(&virtio_vsock_driver); 703 if (ret) 704 destroy_workqueue(virtio_vsock_workqueue); 705 return ret; 706 } 707 708 static void __exit virtio_vsock_exit(void) 709 { 710 unregister_virtio_driver(&virtio_vsock_driver); 711 destroy_workqueue(virtio_vsock_workqueue); 712 } 713 714 module_init(virtio_vsock_init); 715 module_exit(virtio_vsock_exit); 716 MODULE_LICENSE("GPL v2"); 717 MODULE_AUTHOR("Asias He"); 718 MODULE_DESCRIPTION("virtio transport for vsock"); 719 MODULE_DEVICE_TABLE(virtio, id_table); 720