Asias He | 0ea9e1d | 2016-07-28 15:36:33 +0100 | [diff] [blame] | 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 | atomic_t queued_replies; |
| 48 | |
| 49 | /* The following fields are protected by rx_lock. vqs[VSOCK_VQ_RX] |
| 50 | * must be accessed with rx_lock held. |
| 51 | */ |
| 52 | struct mutex rx_lock; |
| 53 | int rx_buf_nr; |
| 54 | int rx_buf_max_nr; |
| 55 | |
| 56 | /* The following fields are protected by event_lock. |
| 57 | * vqs[VSOCK_VQ_EVENT] must be accessed with event_lock held. |
| 58 | */ |
| 59 | struct mutex event_lock; |
| 60 | struct virtio_vsock_event event_list[8]; |
| 61 | |
| 62 | u32 guest_cid; |
| 63 | }; |
| 64 | |
| 65 | static struct virtio_vsock *virtio_vsock_get(void) |
| 66 | { |
| 67 | return the_virtio_vsock; |
| 68 | } |
| 69 | |
| 70 | static u32 virtio_transport_get_local_cid(void) |
| 71 | { |
| 72 | struct virtio_vsock *vsock = virtio_vsock_get(); |
| 73 | |
| 74 | return vsock->guest_cid; |
| 75 | } |
| 76 | |
| 77 | static void |
| 78 | virtio_transport_send_pkt_work(struct work_struct *work) |
| 79 | { |
| 80 | struct virtio_vsock *vsock = |
| 81 | container_of(work, struct virtio_vsock, send_pkt_work); |
| 82 | struct virtqueue *vq; |
| 83 | bool added = false; |
| 84 | bool restart_rx = false; |
| 85 | |
| 86 | mutex_lock(&vsock->tx_lock); |
| 87 | |
| 88 | vq = vsock->vqs[VSOCK_VQ_TX]; |
| 89 | |
| 90 | /* Avoid unnecessary interrupts while we're processing the ring */ |
| 91 | virtqueue_disable_cb(vq); |
| 92 | |
| 93 | for (;;) { |
| 94 | struct virtio_vsock_pkt *pkt; |
| 95 | struct scatterlist hdr, buf, *sgs[2]; |
| 96 | int ret, in_sg = 0, out_sg = 0; |
| 97 | bool reply; |
| 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 | virtqueue_enable_cb(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 | reply = pkt->reply; |
| 112 | |
| 113 | sg_init_one(&hdr, &pkt->hdr, sizeof(pkt->hdr)); |
| 114 | sgs[out_sg++] = &hdr; |
| 115 | if (pkt->buf) { |
| 116 | sg_init_one(&buf, pkt->buf, pkt->len); |
| 117 | sgs[out_sg++] = &buf; |
| 118 | } |
| 119 | |
| 120 | ret = virtqueue_add_sgs(vq, sgs, out_sg, in_sg, pkt, GFP_KERNEL); |
| 121 | if (ret < 0) { |
| 122 | spin_lock_bh(&vsock->send_pkt_list_lock); |
| 123 | list_add(&pkt->list, &vsock->send_pkt_list); |
| 124 | spin_unlock_bh(&vsock->send_pkt_list_lock); |
| 125 | |
| 126 | if (!virtqueue_enable_cb(vq) && ret == -ENOSPC) |
| 127 | continue; /* retry now that we have more space */ |
| 128 | break; |
| 129 | } |
| 130 | |
| 131 | if (reply) { |
| 132 | struct virtqueue *rx_vq = vsock->vqs[VSOCK_VQ_RX]; |
| 133 | int val; |
| 134 | |
| 135 | val = atomic_dec_return(&vsock->queued_replies); |
| 136 | |
| 137 | /* Do we now have resources to resume rx processing? */ |
| 138 | if (val + 1 == virtqueue_get_vring_size(rx_vq)) |
| 139 | restart_rx = true; |
| 140 | } |
| 141 | |
| 142 | added = true; |
| 143 | } |
| 144 | |
| 145 | if (added) |
| 146 | virtqueue_kick(vq); |
| 147 | |
| 148 | mutex_unlock(&vsock->tx_lock); |
| 149 | |
| 150 | if (restart_rx) |
| 151 | queue_work(virtio_vsock_workqueue, &vsock->rx_work); |
| 152 | } |
| 153 | |
| 154 | static int |
| 155 | virtio_transport_send_pkt(struct virtio_vsock_pkt *pkt) |
| 156 | { |
| 157 | struct virtio_vsock *vsock; |
| 158 | int len = pkt->len; |
| 159 | |
| 160 | vsock = virtio_vsock_get(); |
| 161 | if (!vsock) { |
| 162 | virtio_transport_free_pkt(pkt); |
| 163 | return -ENODEV; |
| 164 | } |
| 165 | |
| 166 | if (pkt->reply) |
| 167 | atomic_inc(&vsock->queued_replies); |
| 168 | |
| 169 | spin_lock_bh(&vsock->send_pkt_list_lock); |
| 170 | list_add_tail(&pkt->list, &vsock->send_pkt_list); |
| 171 | spin_unlock_bh(&vsock->send_pkt_list_lock); |
| 172 | |
| 173 | queue_work(virtio_vsock_workqueue, &vsock->send_pkt_work); |
| 174 | return len; |
| 175 | } |
| 176 | |
| 177 | static void virtio_vsock_rx_fill(struct virtio_vsock *vsock) |
| 178 | { |
| 179 | int buf_len = VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE; |
| 180 | struct virtio_vsock_pkt *pkt; |
| 181 | struct scatterlist hdr, buf, *sgs[2]; |
| 182 | struct virtqueue *vq; |
| 183 | int ret; |
| 184 | |
| 185 | vq = vsock->vqs[VSOCK_VQ_RX]; |
| 186 | |
| 187 | do { |
| 188 | pkt = kzalloc(sizeof(*pkt), GFP_KERNEL); |
| 189 | if (!pkt) |
| 190 | break; |
| 191 | |
| 192 | pkt->buf = kmalloc(buf_len, GFP_KERNEL); |
| 193 | if (!pkt->buf) { |
| 194 | virtio_transport_free_pkt(pkt); |
| 195 | break; |
| 196 | } |
| 197 | |
| 198 | pkt->len = buf_len; |
| 199 | |
| 200 | sg_init_one(&hdr, &pkt->hdr, sizeof(pkt->hdr)); |
| 201 | sgs[0] = &hdr; |
| 202 | |
| 203 | sg_init_one(&buf, pkt->buf, buf_len); |
| 204 | sgs[1] = &buf; |
| 205 | ret = virtqueue_add_sgs(vq, sgs, 0, 2, pkt, GFP_KERNEL); |
| 206 | if (ret) { |
| 207 | virtio_transport_free_pkt(pkt); |
| 208 | break; |
| 209 | } |
| 210 | vsock->rx_buf_nr++; |
| 211 | } while (vq->num_free); |
| 212 | if (vsock->rx_buf_nr > vsock->rx_buf_max_nr) |
| 213 | vsock->rx_buf_max_nr = vsock->rx_buf_nr; |
| 214 | virtqueue_kick(vq); |
| 215 | } |
| 216 | |
| 217 | static void virtio_transport_tx_work(struct work_struct *work) |
| 218 | { |
| 219 | struct virtio_vsock *vsock = |
| 220 | container_of(work, struct virtio_vsock, tx_work); |
| 221 | struct virtqueue *vq; |
| 222 | bool added = false; |
| 223 | |
| 224 | vq = vsock->vqs[VSOCK_VQ_TX]; |
| 225 | mutex_lock(&vsock->tx_lock); |
| 226 | do { |
| 227 | struct virtio_vsock_pkt *pkt; |
| 228 | unsigned int len; |
| 229 | |
| 230 | virtqueue_disable_cb(vq); |
| 231 | while ((pkt = virtqueue_get_buf(vq, &len)) != NULL) { |
| 232 | virtio_transport_free_pkt(pkt); |
| 233 | added = true; |
| 234 | } |
| 235 | } while (!virtqueue_enable_cb(vq)); |
| 236 | mutex_unlock(&vsock->tx_lock); |
| 237 | |
| 238 | if (added) |
| 239 | queue_work(virtio_vsock_workqueue, &vsock->send_pkt_work); |
| 240 | } |
| 241 | |
| 242 | /* Is there space left for replies to rx packets? */ |
| 243 | static bool virtio_transport_more_replies(struct virtio_vsock *vsock) |
| 244 | { |
| 245 | struct virtqueue *vq = vsock->vqs[VSOCK_VQ_RX]; |
| 246 | int val; |
| 247 | |
| 248 | smp_rmb(); /* paired with atomic_inc() and atomic_dec_return() */ |
| 249 | val = atomic_read(&vsock->queued_replies); |
| 250 | |
| 251 | return val < virtqueue_get_vring_size(vq); |
| 252 | } |
| 253 | |
| 254 | static void virtio_transport_rx_work(struct work_struct *work) |
| 255 | { |
| 256 | struct virtio_vsock *vsock = |
| 257 | container_of(work, struct virtio_vsock, rx_work); |
| 258 | struct virtqueue *vq; |
| 259 | |
| 260 | vq = vsock->vqs[VSOCK_VQ_RX]; |
| 261 | |
| 262 | mutex_lock(&vsock->rx_lock); |
| 263 | |
| 264 | do { |
| 265 | virtqueue_disable_cb(vq); |
| 266 | for (;;) { |
| 267 | struct virtio_vsock_pkt *pkt; |
| 268 | unsigned int len; |
| 269 | |
| 270 | if (!virtio_transport_more_replies(vsock)) { |
| 271 | /* Stop rx until the device processes already |
| 272 | * pending replies. Leave rx virtqueue |
| 273 | * callbacks disabled. |
| 274 | */ |
| 275 | goto out; |
| 276 | } |
| 277 | |
| 278 | pkt = virtqueue_get_buf(vq, &len); |
| 279 | if (!pkt) { |
| 280 | break; |
| 281 | } |
| 282 | |
| 283 | vsock->rx_buf_nr--; |
| 284 | |
| 285 | /* Drop short/long packets */ |
| 286 | if (unlikely(len < sizeof(pkt->hdr) || |
| 287 | len > sizeof(pkt->hdr) + pkt->len)) { |
| 288 | virtio_transport_free_pkt(pkt); |
| 289 | continue; |
| 290 | } |
| 291 | |
| 292 | pkt->len = len - sizeof(pkt->hdr); |
| 293 | virtio_transport_recv_pkt(pkt); |
| 294 | } |
| 295 | } while (!virtqueue_enable_cb(vq)); |
| 296 | |
| 297 | out: |
| 298 | if (vsock->rx_buf_nr < vsock->rx_buf_max_nr / 2) |
| 299 | virtio_vsock_rx_fill(vsock); |
| 300 | mutex_unlock(&vsock->rx_lock); |
| 301 | } |
| 302 | |
| 303 | /* event_lock must be held */ |
| 304 | static int virtio_vsock_event_fill_one(struct virtio_vsock *vsock, |
| 305 | struct virtio_vsock_event *event) |
| 306 | { |
| 307 | struct scatterlist sg; |
| 308 | struct virtqueue *vq; |
| 309 | |
| 310 | vq = vsock->vqs[VSOCK_VQ_EVENT]; |
| 311 | |
| 312 | sg_init_one(&sg, event, sizeof(*event)); |
| 313 | |
| 314 | return virtqueue_add_inbuf(vq, &sg, 1, event, GFP_KERNEL); |
| 315 | } |
| 316 | |
| 317 | /* event_lock must be held */ |
| 318 | static void virtio_vsock_event_fill(struct virtio_vsock *vsock) |
| 319 | { |
| 320 | size_t i; |
| 321 | |
| 322 | for (i = 0; i < ARRAY_SIZE(vsock->event_list); i++) { |
| 323 | struct virtio_vsock_event *event = &vsock->event_list[i]; |
| 324 | |
| 325 | virtio_vsock_event_fill_one(vsock, event); |
| 326 | } |
| 327 | |
| 328 | virtqueue_kick(vsock->vqs[VSOCK_VQ_EVENT]); |
| 329 | } |
| 330 | |
| 331 | static void virtio_vsock_reset_sock(struct sock *sk) |
| 332 | { |
| 333 | lock_sock(sk); |
| 334 | sk->sk_state = SS_UNCONNECTED; |
| 335 | sk->sk_err = ECONNRESET; |
| 336 | sk->sk_error_report(sk); |
| 337 | release_sock(sk); |
| 338 | } |
| 339 | |
| 340 | static void virtio_vsock_update_guest_cid(struct virtio_vsock *vsock) |
| 341 | { |
| 342 | struct virtio_device *vdev = vsock->vdev; |
| 343 | u64 guest_cid; |
| 344 | |
| 345 | vdev->config->get(vdev, offsetof(struct virtio_vsock_config, guest_cid), |
| 346 | &guest_cid, sizeof(guest_cid)); |
| 347 | vsock->guest_cid = le64_to_cpu(guest_cid); |
| 348 | } |
| 349 | |
| 350 | /* event_lock must be held */ |
| 351 | static void virtio_vsock_event_handle(struct virtio_vsock *vsock, |
| 352 | struct virtio_vsock_event *event) |
| 353 | { |
| 354 | switch (le32_to_cpu(event->id)) { |
| 355 | case VIRTIO_VSOCK_EVENT_TRANSPORT_RESET: |
| 356 | virtio_vsock_update_guest_cid(vsock); |
| 357 | vsock_for_each_connected_socket(virtio_vsock_reset_sock); |
| 358 | break; |
| 359 | } |
| 360 | } |
| 361 | |
| 362 | static void virtio_transport_event_work(struct work_struct *work) |
| 363 | { |
| 364 | struct virtio_vsock *vsock = |
| 365 | container_of(work, struct virtio_vsock, event_work); |
| 366 | struct virtqueue *vq; |
| 367 | |
| 368 | vq = vsock->vqs[VSOCK_VQ_EVENT]; |
| 369 | |
| 370 | mutex_lock(&vsock->event_lock); |
| 371 | |
| 372 | do { |
| 373 | struct virtio_vsock_event *event; |
| 374 | unsigned int len; |
| 375 | |
| 376 | virtqueue_disable_cb(vq); |
| 377 | while ((event = virtqueue_get_buf(vq, &len)) != NULL) { |
| 378 | if (len == sizeof(*event)) |
| 379 | virtio_vsock_event_handle(vsock, event); |
| 380 | |
| 381 | virtio_vsock_event_fill_one(vsock, event); |
| 382 | } |
| 383 | } while (!virtqueue_enable_cb(vq)); |
| 384 | |
| 385 | virtqueue_kick(vsock->vqs[VSOCK_VQ_EVENT]); |
| 386 | |
| 387 | mutex_unlock(&vsock->event_lock); |
| 388 | } |
| 389 | |
| 390 | static void virtio_vsock_event_done(struct virtqueue *vq) |
| 391 | { |
| 392 | struct virtio_vsock *vsock = vq->vdev->priv; |
| 393 | |
| 394 | if (!vsock) |
| 395 | return; |
| 396 | queue_work(virtio_vsock_workqueue, &vsock->event_work); |
| 397 | } |
| 398 | |
| 399 | static void virtio_vsock_tx_done(struct virtqueue *vq) |
| 400 | { |
| 401 | struct virtio_vsock *vsock = vq->vdev->priv; |
| 402 | |
| 403 | if (!vsock) |
| 404 | return; |
| 405 | queue_work(virtio_vsock_workqueue, &vsock->tx_work); |
| 406 | } |
| 407 | |
| 408 | static void virtio_vsock_rx_done(struct virtqueue *vq) |
| 409 | { |
| 410 | struct virtio_vsock *vsock = vq->vdev->priv; |
| 411 | |
| 412 | if (!vsock) |
| 413 | return; |
| 414 | queue_work(virtio_vsock_workqueue, &vsock->rx_work); |
| 415 | } |
| 416 | |
| 417 | static struct virtio_transport virtio_transport = { |
| 418 | .transport = { |
| 419 | .get_local_cid = virtio_transport_get_local_cid, |
| 420 | |
| 421 | .init = virtio_transport_do_socket_init, |
| 422 | .destruct = virtio_transport_destruct, |
| 423 | .release = virtio_transport_release, |
| 424 | .connect = virtio_transport_connect, |
| 425 | .shutdown = virtio_transport_shutdown, |
| 426 | |
| 427 | .dgram_bind = virtio_transport_dgram_bind, |
| 428 | .dgram_dequeue = virtio_transport_dgram_dequeue, |
| 429 | .dgram_enqueue = virtio_transport_dgram_enqueue, |
| 430 | .dgram_allow = virtio_transport_dgram_allow, |
| 431 | |
| 432 | .stream_dequeue = virtio_transport_stream_dequeue, |
| 433 | .stream_enqueue = virtio_transport_stream_enqueue, |
| 434 | .stream_has_data = virtio_transport_stream_has_data, |
| 435 | .stream_has_space = virtio_transport_stream_has_space, |
| 436 | .stream_rcvhiwat = virtio_transport_stream_rcvhiwat, |
| 437 | .stream_is_active = virtio_transport_stream_is_active, |
| 438 | .stream_allow = virtio_transport_stream_allow, |
| 439 | |
| 440 | .notify_poll_in = virtio_transport_notify_poll_in, |
| 441 | .notify_poll_out = virtio_transport_notify_poll_out, |
| 442 | .notify_recv_init = virtio_transport_notify_recv_init, |
| 443 | .notify_recv_pre_block = virtio_transport_notify_recv_pre_block, |
| 444 | .notify_recv_pre_dequeue = virtio_transport_notify_recv_pre_dequeue, |
| 445 | .notify_recv_post_dequeue = virtio_transport_notify_recv_post_dequeue, |
| 446 | .notify_send_init = virtio_transport_notify_send_init, |
| 447 | .notify_send_pre_block = virtio_transport_notify_send_pre_block, |
| 448 | .notify_send_pre_enqueue = virtio_transport_notify_send_pre_enqueue, |
| 449 | .notify_send_post_enqueue = virtio_transport_notify_send_post_enqueue, |
| 450 | |
| 451 | .set_buffer_size = virtio_transport_set_buffer_size, |
| 452 | .set_min_buffer_size = virtio_transport_set_min_buffer_size, |
| 453 | .set_max_buffer_size = virtio_transport_set_max_buffer_size, |
| 454 | .get_buffer_size = virtio_transport_get_buffer_size, |
| 455 | .get_min_buffer_size = virtio_transport_get_min_buffer_size, |
| 456 | .get_max_buffer_size = virtio_transport_get_max_buffer_size, |
| 457 | }, |
| 458 | |
| 459 | .send_pkt = virtio_transport_send_pkt, |
| 460 | }; |
| 461 | |
| 462 | static int virtio_vsock_probe(struct virtio_device *vdev) |
| 463 | { |
| 464 | vq_callback_t *callbacks[] = { |
| 465 | virtio_vsock_rx_done, |
| 466 | virtio_vsock_tx_done, |
| 467 | virtio_vsock_event_done, |
| 468 | }; |
| 469 | static const char * const names[] = { |
| 470 | "rx", |
| 471 | "tx", |
| 472 | "event", |
| 473 | }; |
| 474 | struct virtio_vsock *vsock = NULL; |
| 475 | int ret; |
| 476 | |
| 477 | ret = mutex_lock_interruptible(&the_virtio_vsock_mutex); |
| 478 | if (ret) |
| 479 | return ret; |
| 480 | |
| 481 | /* Only one virtio-vsock device per guest is supported */ |
| 482 | if (the_virtio_vsock) { |
| 483 | ret = -EBUSY; |
| 484 | goto out; |
| 485 | } |
| 486 | |
| 487 | vsock = kzalloc(sizeof(*vsock), GFP_KERNEL); |
| 488 | if (!vsock) { |
| 489 | ret = -ENOMEM; |
| 490 | goto out; |
| 491 | } |
| 492 | |
| 493 | vsock->vdev = vdev; |
| 494 | |
| 495 | ret = vsock->vdev->config->find_vqs(vsock->vdev, VSOCK_VQ_MAX, |
| 496 | vsock->vqs, callbacks, names); |
| 497 | if (ret < 0) |
| 498 | goto out; |
| 499 | |
| 500 | virtio_vsock_update_guest_cid(vsock); |
| 501 | |
| 502 | ret = vsock_core_init(&virtio_transport.transport); |
| 503 | if (ret < 0) |
| 504 | goto out_vqs; |
| 505 | |
| 506 | vsock->rx_buf_nr = 0; |
| 507 | vsock->rx_buf_max_nr = 0; |
| 508 | atomic_set(&vsock->queued_replies, 0); |
| 509 | |
| 510 | vdev->priv = vsock; |
| 511 | the_virtio_vsock = vsock; |
| 512 | mutex_init(&vsock->tx_lock); |
| 513 | mutex_init(&vsock->rx_lock); |
| 514 | mutex_init(&vsock->event_lock); |
| 515 | spin_lock_init(&vsock->send_pkt_list_lock); |
| 516 | INIT_LIST_HEAD(&vsock->send_pkt_list); |
| 517 | INIT_WORK(&vsock->rx_work, virtio_transport_rx_work); |
| 518 | INIT_WORK(&vsock->tx_work, virtio_transport_tx_work); |
| 519 | INIT_WORK(&vsock->event_work, virtio_transport_event_work); |
| 520 | INIT_WORK(&vsock->send_pkt_work, virtio_transport_send_pkt_work); |
| 521 | |
| 522 | mutex_lock(&vsock->rx_lock); |
| 523 | virtio_vsock_rx_fill(vsock); |
| 524 | mutex_unlock(&vsock->rx_lock); |
| 525 | |
| 526 | mutex_lock(&vsock->event_lock); |
| 527 | virtio_vsock_event_fill(vsock); |
| 528 | mutex_unlock(&vsock->event_lock); |
| 529 | |
| 530 | mutex_unlock(&the_virtio_vsock_mutex); |
| 531 | return 0; |
| 532 | |
| 533 | out_vqs: |
| 534 | vsock->vdev->config->del_vqs(vsock->vdev); |
| 535 | out: |
| 536 | kfree(vsock); |
| 537 | mutex_unlock(&the_virtio_vsock_mutex); |
| 538 | return ret; |
| 539 | } |
| 540 | |
| 541 | static void virtio_vsock_remove(struct virtio_device *vdev) |
| 542 | { |
| 543 | struct virtio_vsock *vsock = vdev->priv; |
| 544 | struct virtio_vsock_pkt *pkt; |
| 545 | |
| 546 | flush_work(&vsock->rx_work); |
| 547 | flush_work(&vsock->tx_work); |
| 548 | flush_work(&vsock->event_work); |
| 549 | flush_work(&vsock->send_pkt_work); |
| 550 | |
| 551 | vdev->config->reset(vdev); |
| 552 | |
| 553 | mutex_lock(&vsock->rx_lock); |
| 554 | while ((pkt = virtqueue_detach_unused_buf(vsock->vqs[VSOCK_VQ_RX]))) |
| 555 | virtio_transport_free_pkt(pkt); |
| 556 | mutex_unlock(&vsock->rx_lock); |
| 557 | |
| 558 | mutex_lock(&vsock->tx_lock); |
| 559 | while ((pkt = virtqueue_detach_unused_buf(vsock->vqs[VSOCK_VQ_TX]))) |
| 560 | virtio_transport_free_pkt(pkt); |
| 561 | mutex_unlock(&vsock->tx_lock); |
| 562 | |
| 563 | spin_lock_bh(&vsock->send_pkt_list_lock); |
| 564 | while (!list_empty(&vsock->send_pkt_list)) { |
| 565 | pkt = list_first_entry(&vsock->send_pkt_list, |
| 566 | struct virtio_vsock_pkt, list); |
| 567 | list_del(&pkt->list); |
| 568 | virtio_transport_free_pkt(pkt); |
| 569 | } |
| 570 | spin_unlock_bh(&vsock->send_pkt_list_lock); |
| 571 | |
| 572 | mutex_lock(&the_virtio_vsock_mutex); |
| 573 | the_virtio_vsock = NULL; |
| 574 | vsock_core_exit(); |
| 575 | mutex_unlock(&the_virtio_vsock_mutex); |
| 576 | |
| 577 | vdev->config->del_vqs(vdev); |
| 578 | |
| 579 | kfree(vsock); |
| 580 | } |
| 581 | |
| 582 | static struct virtio_device_id id_table[] = { |
| 583 | { VIRTIO_ID_VSOCK, VIRTIO_DEV_ANY_ID }, |
| 584 | { 0 }, |
| 585 | }; |
| 586 | |
| 587 | static unsigned int features[] = { |
| 588 | }; |
| 589 | |
| 590 | static struct virtio_driver virtio_vsock_driver = { |
| 591 | .feature_table = features, |
| 592 | .feature_table_size = ARRAY_SIZE(features), |
| 593 | .driver.name = KBUILD_MODNAME, |
| 594 | .driver.owner = THIS_MODULE, |
| 595 | .id_table = id_table, |
| 596 | .probe = virtio_vsock_probe, |
| 597 | .remove = virtio_vsock_remove, |
| 598 | }; |
| 599 | |
| 600 | static int __init virtio_vsock_init(void) |
| 601 | { |
| 602 | int ret; |
| 603 | |
| 604 | virtio_vsock_workqueue = alloc_workqueue("virtio_vsock", 0, 0); |
| 605 | if (!virtio_vsock_workqueue) |
| 606 | return -ENOMEM; |
| 607 | ret = register_virtio_driver(&virtio_vsock_driver); |
| 608 | if (ret) |
| 609 | destroy_workqueue(virtio_vsock_workqueue); |
| 610 | return ret; |
| 611 | } |
| 612 | |
| 613 | static void __exit virtio_vsock_exit(void) |
| 614 | { |
| 615 | unregister_virtio_driver(&virtio_vsock_driver); |
| 616 | destroy_workqueue(virtio_vsock_workqueue); |
| 617 | } |
| 618 | |
| 619 | module_init(virtio_vsock_init); |
| 620 | module_exit(virtio_vsock_exit); |
| 621 | MODULE_LICENSE("GPL v2"); |
| 622 | MODULE_AUTHOR("Asias He"); |
| 623 | MODULE_DESCRIPTION("virtio transport for vsock"); |
| 624 | MODULE_DEVICE_TABLE(virtio, id_table); |