net/vmw_vsock/virtio_transport_common.c

   1 /*
   2  * common code for virtio 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/spinlock.h>
  11 #include <linux/module.h>
  12 #include <linux/ctype.h>
  13 #include <linux/list.h>
  14 #include <linux/virtio.h>
  15 #include <linux/virtio_ids.h>
  16 #include <linux/virtio_config.h>
  17 #include <linux/virtio_vsock.h>
  18
  19 #include <net/sock.h>
  20 #include <net/af_vsock.h>
  21
  22 #define CREATE_TRACE_POINTS
  23 #include <trace/events/vsock_virtio_transport_common.h>
  24
  25 /* How long to wait for graceful shutdown of a connection */
  26 #define VSOCK_CLOSE_TIMEOUT (8 * HZ)
  27
  28 static const struct virtio_transport *virtio_transport_get_ops(void)
  29 {
  30         const struct vsock_transport *t = vsock_core_get_transport();
  31
  32         return container_of(t, struct virtio_transport, transport);
  33 }
  34
  35 static struct virtio_vsock_pkt *
  36 virtio_transport_alloc_pkt(struct virtio_vsock_pkt_info *info,
  37                            size_t len,
  38                            u32 src_cid,
  39                            u32 src_port,
  40                            u32 dst_cid,
  41                            u32 dst_port)
  42 {
  43         struct virtio_vsock_pkt *pkt;
  44         int err;
  45
  46         pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
  47         if (!pkt)
  48                 return NULL;
  49
  50         pkt->hdr.type           = cpu_to_le16(info->type);
  51         pkt->hdr.op             = cpu_to_le16(info->op);
  52         pkt->hdr.src_cid        = cpu_to_le64(src_cid);
  53         pkt->hdr.dst_cid        = cpu_to_le64(dst_cid);
  54         pkt->hdr.src_port       = cpu_to_le32(src_port);
  55         pkt->hdr.dst_port       = cpu_to_le32(dst_port);
  56         pkt->hdr.flags          = cpu_to_le32(info->flags);
  57         pkt->len                = len;
  58         pkt->hdr.len            = cpu_to_le32(len);
  59         pkt->reply              = info->reply;
  60
  61         if (info->msg && len > 0) {
  62                 pkt->buf = kmalloc(len, GFP_KERNEL);
  63                 if (!pkt->buf)
  64                         goto out_pkt;
  65                 err = memcpy_from_msg(pkt->buf, info->msg, len);
  66                 if (err)
  67                         goto out;
  68         }
  69
  70         trace_virtio_transport_alloc_pkt(src_cid, src_port,
  71                                          dst_cid, dst_port,
  72                                          len,
  73                                          info->type,
  74                                          info->op,
  75                                          info->flags);
  76
  77         return pkt;
  78
  79 out:
  80         kfree(pkt->buf);
  81 out_pkt:
  82         kfree(pkt);
  83         return NULL;
  84 }
  85
  86 static int virtio_transport_send_pkt_info(struct vsock_sock *vsk,
  87                                           struct virtio_vsock_pkt_info *info)
  88 {
  89         u32 src_cid, src_port, dst_cid, dst_port;
  90         struct virtio_vsock_sock *vvs;
  91         struct virtio_vsock_pkt *pkt;
  92         u32 pkt_len = info->pkt_len;
  93
  94         src_cid = vm_sockets_get_local_cid();
  95         src_port = vsk->local_addr.svm_port;
  96         if (!info->remote_cid) {
  97                 dst_cid = vsk->remote_addr.svm_cid;
  98                 dst_port = vsk->remote_addr.svm_port;
  99         } else {
 100                 dst_cid = info->remote_cid;
 101                 dst_port = info->remote_port;
 102         }
 103
 104         vvs = vsk->trans;
 105
 106         /* we can send less than pkt_len bytes */
 107         if (pkt_len > VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE)
 108                 pkt_len = VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE;
 109
 110         /* virtio_transport_get_credit might return less than pkt_len credit */
 111         pkt_len = virtio_transport_get_credit(vvs, pkt_len);
 112
 113         /* Do not send zero length OP_RW pkt */
 114         if (pkt_len == 0 && info->op == VIRTIO_VSOCK_OP_RW)
 115                 return pkt_len;
 116
 117         pkt = virtio_transport_alloc_pkt(info, pkt_len,
 118                                          src_cid, src_port,
 119                                          dst_cid, dst_port);
 120         if (!pkt) {
 121                 virtio_transport_put_credit(vvs, pkt_len);
 122                 return -ENOMEM;
 123         }
 124
 125         virtio_transport_inc_tx_pkt(vvs, pkt);
 126
 127         return virtio_transport_get_ops()->send_pkt(pkt);
 128 }
 129
 130 static void virtio_transport_inc_rx_pkt(struct virtio_vsock_sock *vvs,
 131                                         struct virtio_vsock_pkt *pkt)
 132 {
 133         vvs->rx_bytes += pkt->len;
 134 }
 135
 136 static void virtio_transport_dec_rx_pkt(struct virtio_vsock_sock *vvs,
 137                                         struct virtio_vsock_pkt *pkt)
 138 {
 139         vvs->rx_bytes -= pkt->len;
 140         vvs->fwd_cnt += pkt->len;
 141 }
 142
 143 void virtio_transport_inc_tx_pkt(struct virtio_vsock_sock *vvs, struct virtio_vsock_pkt *pkt)
 144 {
 145         spin_lock_bh(&vvs->tx_lock);
 146         pkt->hdr.fwd_cnt = cpu_to_le32(vvs->fwd_cnt);
 147         pkt->hdr.buf_alloc = cpu_to_le32(vvs->buf_alloc);
 148         spin_unlock_bh(&vvs->tx_lock);
 149 }
 150 EXPORT_SYMBOL_GPL(virtio_transport_inc_tx_pkt);
 151
 152 u32 virtio_transport_get_credit(struct virtio_vsock_sock *vvs, u32 credit)
 153 {
 154         u32 ret;
 155
 156         spin_lock_bh(&vvs->tx_lock);
 157         ret = vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt);
 158         if (ret > credit)
 159                 ret = credit;
 160         vvs->tx_cnt += ret;
 161         spin_unlock_bh(&vvs->tx_lock);
 162
 163         return ret;
 164 }
 165 EXPORT_SYMBOL_GPL(virtio_transport_get_credit);
 166
 167 void virtio_transport_put_credit(struct virtio_vsock_sock *vvs, u32 credit)
 168 {
 169         spin_lock_bh(&vvs->tx_lock);
 170         vvs->tx_cnt -= credit;
 171         spin_unlock_bh(&vvs->tx_lock);
 172 }
 173 EXPORT_SYMBOL_GPL(virtio_transport_put_credit);
 174
 175 static int virtio_transport_send_credit_update(struct vsock_sock *vsk,
 176                                                int type,
 177                                                struct virtio_vsock_hdr *hdr)
 178 {
 179         struct virtio_vsock_pkt_info info = {
 180                 .op = VIRTIO_VSOCK_OP_CREDIT_UPDATE,
 181                 .type = type,
 182         };
 183
 184         return virtio_transport_send_pkt_info(vsk, &info);
 185 }
 186
 187 static ssize_t
 188 virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
 189                                    struct msghdr *msg,
 190                                    size_t len)
 191 {
 192         struct virtio_vsock_sock *vvs = vsk->trans;
 193         struct virtio_vsock_pkt *pkt;
 194         size_t bytes, total = 0;
 195         int err = -EFAULT;
 196
 197         spin_lock_bh(&vvs->rx_lock);
 198         while (total < len && !list_empty(&vvs->rx_queue)) {
 199                 pkt = list_first_entry(&vvs->rx_queue,
 200                                        struct virtio_vsock_pkt, list);
 201
 202                 bytes = len - total;
 203                 if (bytes > pkt->len - pkt->off)
 204                         bytes = pkt->len - pkt->off;
 205
 206                 /* sk_lock is held by caller so no one else can dequeue.
 207                  * Unlock rx_lock since memcpy_to_msg() may sleep.
 208                  */
 209                 spin_unlock_bh(&vvs->rx_lock);
 210
 211                 err = memcpy_to_msg(msg, pkt->buf + pkt->off, bytes);
 212                 if (err)
 213                         goto out;
 214
 215                 spin_lock_bh(&vvs->rx_lock);
 216
 217                 total += bytes;
 218                 pkt->off += bytes;
 219                 if (pkt->off == pkt->len) {
 220                         virtio_transport_dec_rx_pkt(vvs, pkt);
 221                         list_del(&pkt->list);
 222                         virtio_transport_free_pkt(pkt);
 223                 }
 224         }
 225         spin_unlock_bh(&vvs->rx_lock);
 226
 227         /* Send a credit pkt to peer */
 228         virtio_transport_send_credit_update(vsk, VIRTIO_VSOCK_TYPE_STREAM,
 229                                             NULL);
 230
 231         return total;
 232
 233 out:
 234         if (total)
 235                 err = total;
 236         return err;
 237 }
 238
 239 ssize_t
 240 virtio_transport_stream_dequeue(struct vsock_sock *vsk,
 241                                 struct msghdr *msg,
 242                                 size_t len, int flags)
 243 {
 244         if (flags & MSG_PEEK)
 245                 return -EOPNOTSUPP;
 246
 247         return virtio_transport_stream_do_dequeue(vsk, msg, len);
 248 }
 249 EXPORT_SYMBOL_GPL(virtio_transport_stream_dequeue);
 250
 251 int
 252 virtio_transport_dgram_dequeue(struct vsock_sock *vsk,
 253                                struct msghdr *msg,
 254                                size_t len, int flags)
 255 {
 256         return -EOPNOTSUPP;
 257 }
 258 EXPORT_SYMBOL_GPL(virtio_transport_dgram_dequeue);
 259
 260 s64 virtio_transport_stream_has_data(struct vsock_sock *vsk)
 261 {
 262         struct virtio_vsock_sock *vvs = vsk->trans;
 263         s64 bytes;
 264
 265         spin_lock_bh(&vvs->rx_lock);
 266         bytes = vvs->rx_bytes;
 267         spin_unlock_bh(&vvs->rx_lock);
 268
 269         return bytes;
 270 }
 271 EXPORT_SYMBOL_GPL(virtio_transport_stream_has_data);
 272
 273 static s64 virtio_transport_has_space(struct vsock_sock *vsk)
 274 {
 275         struct virtio_vsock_sock *vvs = vsk->trans;
 276         s64 bytes;
 277
 278         bytes = vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt);
 279         if (bytes < 0)
 280                 bytes = 0;
 281
 282         return bytes;
 283 }
 284
 285 s64 virtio_transport_stream_has_space(struct vsock_sock *vsk)
 286 {
 287         struct virtio_vsock_sock *vvs = vsk->trans;
 288         s64 bytes;
 289
 290         spin_lock_bh(&vvs->tx_lock);
 291         bytes = virtio_transport_has_space(vsk);
 292         spin_unlock_bh(&vvs->tx_lock);
 293
 294         return bytes;
 295 }
 296 EXPORT_SYMBOL_GPL(virtio_transport_stream_has_space);
 297
 298 int virtio_transport_do_socket_init(struct vsock_sock *vsk,
 299                                     struct vsock_sock *psk)
 300 {
 301         struct virtio_vsock_sock *vvs;
 302
 303         vvs = kzalloc(sizeof(*vvs), GFP_KERNEL);
 304         if (!vvs)
 305                 return -ENOMEM;
 306
 307         vsk->trans = vvs;
 308         vvs->vsk = vsk;
 309         if (psk) {
 310                 struct virtio_vsock_sock *ptrans = psk->trans;
 311
 312                 vvs->buf_size   = ptrans->buf_size;
 313                 vvs->buf_size_min = ptrans->buf_size_min;
 314                 vvs->buf_size_max = ptrans->buf_size_max;
 315                 vvs->peer_buf_alloc = ptrans->peer_buf_alloc;
 316         } else {
 317                 vvs->buf_size = VIRTIO_VSOCK_DEFAULT_BUF_SIZE;
 318                 vvs->buf_size_min = VIRTIO_VSOCK_DEFAULT_MIN_BUF_SIZE;
 319                 vvs->buf_size_max = VIRTIO_VSOCK_DEFAULT_MAX_BUF_SIZE;
 320         }
 321
 322         vvs->buf_alloc = vvs->buf_size;
 323
 324         spin_lock_init(&vvs->rx_lock);
 325         spin_lock_init(&vvs->tx_lock);
 326         INIT_LIST_HEAD(&vvs->rx_queue);
 327
 328         return 0;
 329 }
 330 EXPORT_SYMBOL_GPL(virtio_transport_do_socket_init);
 331
 332 u64 virtio_transport_get_buffer_size(struct vsock_sock *vsk)
 333 {
 334         struct virtio_vsock_sock *vvs = vsk->trans;
 335
 336         return vvs->buf_size;
 337 }
 338 EXPORT_SYMBOL_GPL(virtio_transport_get_buffer_size);
 339
 340 u64 virtio_transport_get_min_buffer_size(struct vsock_sock *vsk)
 341 {
 342         struct virtio_vsock_sock *vvs = vsk->trans;
 343
 344         return vvs->buf_size_min;
 345 }
 346 EXPORT_SYMBOL_GPL(virtio_transport_get_min_buffer_size);
 347
 348 u64 virtio_transport_get_max_buffer_size(struct vsock_sock *vsk)
 349 {
 350         struct virtio_vsock_sock *vvs = vsk->trans;
 351
 352         return vvs->buf_size_max;
 353 }
 354 EXPORT_SYMBOL_GPL(virtio_transport_get_max_buffer_size);
 355
 356 void virtio_transport_set_buffer_size(struct vsock_sock *vsk, u64 val)
 357 {
 358         struct virtio_vsock_sock *vvs = vsk->trans;
 359
 360         if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
 361                 val = VIRTIO_VSOCK_MAX_BUF_SIZE;
 362         if (val < vvs->buf_size_min)
 363                 vvs->buf_size_min = val;
 364         if (val > vvs->buf_size_max)
 365                 vvs->buf_size_max = val;
 366         vvs->buf_size = val;
 367         vvs->buf_alloc = val;
 368 }
 369 EXPORT_SYMBOL_GPL(virtio_transport_set_buffer_size);
 370
 371 void virtio_transport_set_min_buffer_size(struct vsock_sock *vsk, u64 val)
 372 {
 373         struct virtio_vsock_sock *vvs = vsk->trans;
 374
 375         if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
 376                 val = VIRTIO_VSOCK_MAX_BUF_SIZE;
 377         if (val > vvs->buf_size)
 378                 vvs->buf_size = val;
 379         vvs->buf_size_min = val;
 380 }
 381 EXPORT_SYMBOL_GPL(virtio_transport_set_min_buffer_size);
 382
 383 void virtio_transport_set_max_buffer_size(struct vsock_sock *vsk, u64 val)
 384 {
 385         struct virtio_vsock_sock *vvs = vsk->trans;
 386
 387         if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
 388                 val = VIRTIO_VSOCK_MAX_BUF_SIZE;
 389         if (val < vvs->buf_size)
 390                 vvs->buf_size = val;
 391         vvs->buf_size_max = val;
 392 }
 393 EXPORT_SYMBOL_GPL(virtio_transport_set_max_buffer_size);
 394
 395 int
 396 virtio_transport_notify_poll_in(struct vsock_sock *vsk,
 397                                 size_t target,
 398                                 bool *data_ready_now)
 399 {
 400         if (vsock_stream_has_data(vsk))
 401                 *data_ready_now = true;
 402         else
 403                 *data_ready_now = false;
 404
 405         return 0;
 406 }
 407 EXPORT_SYMBOL_GPL(virtio_transport_notify_poll_in);
 408
 409 int
 410 virtio_transport_notify_poll_out(struct vsock_sock *vsk,
 411                                  size_t target,
 412                                  bool *space_avail_now)
 413 {
 414         s64 free_space;
 415
 416         free_space = vsock_stream_has_space(vsk);
 417         if (free_space > 0)
 418                 *space_avail_now = true;
 419         else if (free_space == 0)
 420                 *space_avail_now = false;
 421
 422         return 0;
 423 }
 424 EXPORT_SYMBOL_GPL(virtio_transport_notify_poll_out);
 425
 426 int virtio_transport_notify_recv_init(struct vsock_sock *vsk,
 427         size_t target, struct vsock_transport_recv_notify_data *data)
 428 {
 429         return 0;
 430 }
 431 EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_init);
 432
 433 int virtio_transport_notify_recv_pre_block(struct vsock_sock *vsk,
 434         size_t target, struct vsock_transport_recv_notify_data *data)
 435 {
 436         return 0;
 437 }
 438 EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_pre_block);
 439
 440 int virtio_transport_notify_recv_pre_dequeue(struct vsock_sock *vsk,
 441         size_t target, struct vsock_transport_recv_notify_data *data)
 442 {
 443         return 0;
 444 }
 445 EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_pre_dequeue);
 446
 447 int virtio_transport_notify_recv_post_dequeue(struct vsock_sock *vsk,
 448         size_t target, ssize_t copied, bool data_read,
 449         struct vsock_transport_recv_notify_data *data)
 450 {
 451         return 0;
 452 }
 453 EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_post_dequeue);
 454
 455 int virtio_transport_notify_send_init(struct vsock_sock *vsk,
 456         struct vsock_transport_send_notify_data *data)
 457 {
 458         return 0;
 459 }
 460 EXPORT_SYMBOL_GPL(virtio_transport_notify_send_init);
 461
 462 int virtio_transport_notify_send_pre_block(struct vsock_sock *vsk,
 463         struct vsock_transport_send_notify_data *data)
 464 {
 465         return 0;
 466 }
 467 EXPORT_SYMBOL_GPL(virtio_transport_notify_send_pre_block);
 468
 469 int virtio_transport_notify_send_pre_enqueue(struct vsock_sock *vsk,
 470         struct vsock_transport_send_notify_data *data)
 471 {
 472         return 0;
 473 }
 474 EXPORT_SYMBOL_GPL(virtio_transport_notify_send_pre_enqueue);
 475
 476 int virtio_transport_notify_send_post_enqueue(struct vsock_sock *vsk,
 477         ssize_t written, struct vsock_transport_send_notify_data *data)
 478 {
 479         return 0;
 480 }
 481 EXPORT_SYMBOL_GPL(virtio_transport_notify_send_post_enqueue);
 482
 483 u64 virtio_transport_stream_rcvhiwat(struct vsock_sock *vsk)
 484 {
 485         struct virtio_vsock_sock *vvs = vsk->trans;
 486
 487         return vvs->buf_size;
 488 }
 489 EXPORT_SYMBOL_GPL(virtio_transport_stream_rcvhiwat);
 490
 491 bool virtio_transport_stream_is_active(struct vsock_sock *vsk)
 492 {
 493         return true;
 494 }
 495 EXPORT_SYMBOL_GPL(virtio_transport_stream_is_active);
 496
 497 bool virtio_transport_stream_allow(u32 cid, u32 port)
 498 {
 499         return true;
 500 }
 501 EXPORT_SYMBOL_GPL(virtio_transport_stream_allow);
 502
 503 int virtio_transport_dgram_bind(struct vsock_sock *vsk,
 504                                 struct sockaddr_vm *addr)
 505 {
 506         return -EOPNOTSUPP;
 507 }
 508 EXPORT_SYMBOL_GPL(virtio_transport_dgram_bind);
 509
 510 bool virtio_transport_dgram_allow(u32 cid, u32 port)
 511 {
 512         return false;
 513 }
 514 EXPORT_SYMBOL_GPL(virtio_transport_dgram_allow);
 515
 516 int virtio_transport_connect(struct vsock_sock *vsk)
 517 {
 518         struct virtio_vsock_pkt_info info = {
 519                 .op = VIRTIO_VSOCK_OP_REQUEST,
 520                 .type = VIRTIO_VSOCK_TYPE_STREAM,
 521         };
 522
 523         return virtio_transport_send_pkt_info(vsk, &info);
 524 }
 525 EXPORT_SYMBOL_GPL(virtio_transport_connect);
 526
 527 int virtio_transport_shutdown(struct vsock_sock *vsk, int mode)
 528 {
 529         struct virtio_vsock_pkt_info info = {
 530                 .op = VIRTIO_VSOCK_OP_SHUTDOWN,
 531                 .type = VIRTIO_VSOCK_TYPE_STREAM,
 532                 .flags = (mode & RCV_SHUTDOWN ?
 533                           VIRTIO_VSOCK_SHUTDOWN_RCV : 0) |
 534                          (mode & SEND_SHUTDOWN ?
 535                           VIRTIO_VSOCK_SHUTDOWN_SEND : 0),
 536         };
 537
 538         return virtio_transport_send_pkt_info(vsk, &info);
 539 }
 540 EXPORT_SYMBOL_GPL(virtio_transport_shutdown);
 541
 542 int
 543 virtio_transport_dgram_enqueue(struct vsock_sock *vsk,
 544                                struct sockaddr_vm *remote_addr,
 545                                struct msghdr *msg,
 546                                size_t dgram_len)
 547 {
 548         return -EOPNOTSUPP;
 549 }
 550 EXPORT_SYMBOL_GPL(virtio_transport_dgram_enqueue);
 551
 552 ssize_t
 553 virtio_transport_stream_enqueue(struct vsock_sock *vsk,
 554                                 struct msghdr *msg,
 555                                 size_t len)
 556 {
 557         struct virtio_vsock_pkt_info info = {
 558                 .op = VIRTIO_VSOCK_OP_RW,
 559                 .type = VIRTIO_VSOCK_TYPE_STREAM,
 560                 .msg = msg,
 561                 .pkt_len = len,
 562         };
 563
 564         return virtio_transport_send_pkt_info(vsk, &info);
 565 }
 566 EXPORT_SYMBOL_GPL(virtio_transport_stream_enqueue);
 567
 568 void virtio_transport_destruct(struct vsock_sock *vsk)
 569 {
 570         struct virtio_vsock_sock *vvs = vsk->trans;
 571
 572         kfree(vvs);
 573 }
 574 EXPORT_SYMBOL_GPL(virtio_transport_destruct);
 575
 576 static int virtio_transport_reset(struct vsock_sock *vsk,
 577                                   struct virtio_vsock_pkt *pkt)
 578 {
 579         struct virtio_vsock_pkt_info info = {
 580                 .op = VIRTIO_VSOCK_OP_RST,
 581                 .type = VIRTIO_VSOCK_TYPE_STREAM,
 582                 .reply = !!pkt,
 583         };
 584
 585         /* Send RST only if the original pkt is not a RST pkt */
 586         if (pkt && le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
 587                 return 0;
 588
 589         return virtio_transport_send_pkt_info(vsk, &info);
 590 }
 591
 592 /* Normally packets are associated with a socket.  There may be no socket if an
 593  * attempt was made to connect to a socket that does not exist.
 594  */
 595 static int virtio_transport_reset_no_sock(struct virtio_vsock_pkt *pkt)
 596 {
 597         struct virtio_vsock_pkt_info info = {
 598                 .op = VIRTIO_VSOCK_OP_RST,
 599                 .type = le16_to_cpu(pkt->hdr.type),
 600                 .reply = true,
 601         };
 602
 603         /* Send RST only if the original pkt is not a RST pkt */
 604         if (le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
 605                 return 0;
 606
 607         pkt = virtio_transport_alloc_pkt(&info, 0,
 608                                          le64_to_cpu(pkt->hdr.dst_cid),
 609                                          le32_to_cpu(pkt->hdr.dst_port),
 610                                          le64_to_cpu(pkt->hdr.src_cid),
 611                                          le32_to_cpu(pkt->hdr.src_port));
 612         if (!pkt)
 613                 return -ENOMEM;
 614
 615         return virtio_transport_get_ops()->send_pkt(pkt);
 616 }
 617
 618 static void virtio_transport_wait_close(struct sock *sk, long timeout)
 619 {
 620         if (timeout) {
 621                 DEFINE_WAIT_FUNC(wait, woken_wake_function);
 622
 623                 add_wait_queue(sk_sleep(sk), &wait);
 624
 625                 do {
 626                         if (sk_wait_event(sk, &timeout,
 627                                           sock_flag(sk, SOCK_DONE), &wait))
 628                                 break;
 629                 } while (!signal_pending(current) && timeout);
 630
 631                 remove_wait_queue(sk_sleep(sk), &wait);
 632         }
 633 }
 634
 635 static void virtio_transport_do_close(struct vsock_sock *vsk,
 636                                       bool cancel_timeout)
 637 {
 638         struct sock *sk = sk_vsock(vsk);
 639
 640         sock_set_flag(sk, SOCK_DONE);
 641         vsk->peer_shutdown = SHUTDOWN_MASK;
 642         if (vsock_stream_has_data(vsk) <= 0)
 643                 sk->sk_state = SS_DISCONNECTING;
 644         sk->sk_state_change(sk);
 645
 646         if (vsk->close_work_scheduled &&
 647             (!cancel_timeout || cancel_delayed_work(&vsk->close_work))) {
 648                 vsk->close_work_scheduled = false;
 649
 650                 vsock_remove_sock(vsk);
 651
 652                 /* Release refcnt obtained when we scheduled the timeout */
 653                 sock_put(sk);
 654         }
 655 }
 656
 657 static void virtio_transport_close_timeout(struct work_struct *work)
 658 {
 659         struct vsock_sock *vsk =
 660                 container_of(work, struct vsock_sock, close_work.work);
 661         struct sock *sk = sk_vsock(vsk);
 662
 663         sock_hold(sk);
 664         lock_sock(sk);
 665
 666         if (!sock_flag(sk, SOCK_DONE)) {
 667                 (void)virtio_transport_reset(vsk, NULL);
 668
 669                 virtio_transport_do_close(vsk, false);
 670         }
 671
 672         vsk->close_work_scheduled = false;
 673
 674         release_sock(sk);
 675         sock_put(sk);
 676 }
 677
 678 /* User context, vsk->sk is locked */
 679 static bool virtio_transport_close(struct vsock_sock *vsk)
 680 {
 681         struct sock *sk = &vsk->sk;
 682
 683         if (!(sk->sk_state == SS_CONNECTED ||
 684               sk->sk_state == SS_DISCONNECTING))
 685                 return true;
 686
 687         /* Already received SHUTDOWN from peer, reply with RST */
 688         if ((vsk->peer_shutdown & SHUTDOWN_MASK) == SHUTDOWN_MASK) {
 689                 (void)virtio_transport_reset(vsk, NULL);
 690                 return true;
 691         }
 692
 693         if ((sk->sk_shutdown & SHUTDOWN_MASK) != SHUTDOWN_MASK)
 694                 (void)virtio_transport_shutdown(vsk, SHUTDOWN_MASK);
 695
 696         if (sock_flag(sk, SOCK_LINGER) && !(current->flags & PF_EXITING))
 697                 virtio_transport_wait_close(sk, sk->sk_lingertime);
 698
 699         if (sock_flag(sk, SOCK_DONE)) {
 700                 return true;
 701         }
 702
 703         sock_hold(sk);
 704         INIT_DELAYED_WORK(&vsk->close_work,
 705                           virtio_transport_close_timeout);
 706         vsk->close_work_scheduled = true;
 707         schedule_delayed_work(&vsk->close_work, VSOCK_CLOSE_TIMEOUT);
 708         return false;
 709 }
 710
 711 void virtio_transport_release(struct vsock_sock *vsk)
 712 {
 713         struct sock *sk = &vsk->sk;
 714         bool remove_sock = true;
 715
 716         lock_sock(sk);
 717         if (sk->sk_type == SOCK_STREAM)
 718                 remove_sock = virtio_transport_close(vsk);
 719         release_sock(sk);
 720
 721         if (remove_sock)
 722                 vsock_remove_sock(vsk);
 723 }
 724 EXPORT_SYMBOL_GPL(virtio_transport_release);
 725
 726 static int
 727 virtio_transport_recv_connecting(struct sock *sk,
 728                                  struct virtio_vsock_pkt *pkt)
 729 {
 730         struct vsock_sock *vsk = vsock_sk(sk);
 731         int err;
 732         int skerr;
 733
 734         switch (le16_to_cpu(pkt->hdr.op)) {
 735         case VIRTIO_VSOCK_OP_RESPONSE:
 736                 sk->sk_state = SS_CONNECTED;
 737                 sk->sk_socket->state = SS_CONNECTED;
 738                 vsock_insert_connected(vsk);
 739                 sk->sk_state_change(sk);
 740                 break;
 741         case VIRTIO_VSOCK_OP_INVALID:
 742                 break;
 743         case VIRTIO_VSOCK_OP_RST:
 744                 skerr = ECONNRESET;
 745                 err = 0;
 746                 goto destroy;
 747         default:
 748                 skerr = EPROTO;
 749                 err = -EINVAL;
 750                 goto destroy;
 751         }
 752         return 0;
 753
 754 destroy:
 755         virtio_transport_reset(vsk, pkt);
 756         sk->sk_state = SS_UNCONNECTED;
 757         sk->sk_err = skerr;
 758         sk->sk_error_report(sk);
 759         return err;
 760 }
 761
 762 static int
 763 virtio_transport_recv_connected(struct sock *sk,
 764                                 struct virtio_vsock_pkt *pkt)
 765 {
 766         struct vsock_sock *vsk = vsock_sk(sk);
 767         struct virtio_vsock_sock *vvs = vsk->trans;
 768         int err = 0;
 769
 770         switch (le16_to_cpu(pkt->hdr.op)) {
 771         case VIRTIO_VSOCK_OP_RW:
 772                 pkt->len = le32_to_cpu(pkt->hdr.len);
 773                 pkt->off = 0;
 774
 775                 spin_lock_bh(&vvs->rx_lock);
 776                 virtio_transport_inc_rx_pkt(vvs, pkt);
 777                 list_add_tail(&pkt->list, &vvs->rx_queue);
 778                 spin_unlock_bh(&vvs->rx_lock);
 779
 780                 sk->sk_data_ready(sk);
 781                 return err;
 782         case VIRTIO_VSOCK_OP_CREDIT_UPDATE:
 783                 sk->sk_write_space(sk);
 784                 break;
 785         case VIRTIO_VSOCK_OP_SHUTDOWN:
 786                 if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SHUTDOWN_RCV)
 787                         vsk->peer_shutdown |= RCV_SHUTDOWN;
 788                 if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SHUTDOWN_SEND)
 789                         vsk->peer_shutdown |= SEND_SHUTDOWN;
 790                 if (vsk->peer_shutdown == SHUTDOWN_MASK &&
 791                     vsock_stream_has_data(vsk) <= 0)
 792                         sk->sk_state = SS_DISCONNECTING;
 793                 if (le32_to_cpu(pkt->hdr.flags))
 794                         sk->sk_state_change(sk);
 795                 break;
 796         case VIRTIO_VSOCK_OP_RST:
 797                 virtio_transport_do_close(vsk, true);
 798                 break;
 799         default:
 800                 err = -EINVAL;
 801                 break;
 802         }
 803
 804         virtio_transport_free_pkt(pkt);
 805         return err;
 806 }
 807
 808 static void
 809 virtio_transport_recv_disconnecting(struct sock *sk,
 810                                     struct virtio_vsock_pkt *pkt)
 811 {
 812         struct vsock_sock *vsk = vsock_sk(sk);
 813
 814         if (le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
 815                 virtio_transport_do_close(vsk, true);
 816 }
 817
 818 static int
 819 virtio_transport_send_response(struct vsock_sock *vsk,
 820                                struct virtio_vsock_pkt *pkt)
 821 {
 822         struct virtio_vsock_pkt_info info = {
 823                 .op = VIRTIO_VSOCK_OP_RESPONSE,
 824                 .type = VIRTIO_VSOCK_TYPE_STREAM,
 825                 .remote_cid = le64_to_cpu(pkt->hdr.src_cid),
 826                 .remote_port = le32_to_cpu(pkt->hdr.src_port),
 827                 .reply = true,
 828         };
 829
 830         return virtio_transport_send_pkt_info(vsk, &info);
 831 }
 832
 833 /* Handle server socket */
 834 static int
 835 virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt)
 836 {
 837         struct vsock_sock *vsk = vsock_sk(sk);
 838         struct vsock_sock *vchild;
 839         struct sock *child;
 840
 841         if (le16_to_cpu(pkt->hdr.op) != VIRTIO_VSOCK_OP_REQUEST) {
 842                 virtio_transport_reset(vsk, pkt);
 843                 return -EINVAL;
 844         }
 845
 846         if (sk_acceptq_is_full(sk)) {
 847                 virtio_transport_reset(vsk, pkt);
 848                 return -ENOMEM;
 849         }
 850
 851         child = __vsock_create(sock_net(sk), NULL, sk, GFP_KERNEL,
 852                                sk->sk_type, 0);
 853         if (!child) {
 854                 virtio_transport_reset(vsk, pkt);
 855                 return -ENOMEM;
 856         }
 857
 858         sk->sk_ack_backlog++;
 859
 860         lock_sock_nested(child, SINGLE_DEPTH_NESTING);
 861
 862         child->sk_state = SS_CONNECTED;
 863
 864         vchild = vsock_sk(child);
 865         vsock_addr_init(&vchild->local_addr, le64_to_cpu(pkt->hdr.dst_cid),
 866                         le32_to_cpu(pkt->hdr.dst_port));
 867         vsock_addr_init(&vchild->remote_addr, le64_to_cpu(pkt->hdr.src_cid),
 868                         le32_to_cpu(pkt->hdr.src_port));
 869
 870         vsock_insert_connected(vchild);
 871         vsock_enqueue_accept(sk, child);
 872         virtio_transport_send_response(vchild, pkt);
 873
 874         release_sock(child);
 875
 876         sk->sk_data_ready(sk);
 877         return 0;
 878 }
 879
 880 static bool virtio_transport_space_update(struct sock *sk,
 881                                           struct virtio_vsock_pkt *pkt)
 882 {
 883         struct vsock_sock *vsk = vsock_sk(sk);
 884         struct virtio_vsock_sock *vvs = vsk->trans;
 885         bool space_available;
 886
 887         /* buf_alloc and fwd_cnt is always included in the hdr */
 888         spin_lock_bh(&vvs->tx_lock);
 889         vvs->peer_buf_alloc = le32_to_cpu(pkt->hdr.buf_alloc);
 890         vvs->peer_fwd_cnt = le32_to_cpu(pkt->hdr.fwd_cnt);
 891         space_available = virtio_transport_has_space(vsk);
 892         spin_unlock_bh(&vvs->tx_lock);
 893         return space_available;
 894 }
 895
 896 /* We are under the virtio-vsock's vsock->rx_lock or vhost-vsock's vq->mutex
 897  * lock.
 898  */
 899 void virtio_transport_recv_pkt(struct virtio_vsock_pkt *pkt)
 900 {
 901         struct sockaddr_vm src, dst;
 902         struct vsock_sock *vsk;
 903         struct sock *sk;
 904         bool space_available;
 905
 906         vsock_addr_init(&src, le64_to_cpu(pkt->hdr.src_cid),
 907                         le32_to_cpu(pkt->hdr.src_port));
 908         vsock_addr_init(&dst, le64_to_cpu(pkt->hdr.dst_cid),
 909                         le32_to_cpu(pkt->hdr.dst_port));
 910
 911         trace_virtio_transport_recv_pkt(src.svm_cid, src.svm_port,
 912                                         dst.svm_cid, dst.svm_port,
 913                                         le32_to_cpu(pkt->hdr.len),
 914                                         le16_to_cpu(pkt->hdr.type),
 915                                         le16_to_cpu(pkt->hdr.op),
 916                                         le32_to_cpu(pkt->hdr.flags),
 917                                         le32_to_cpu(pkt->hdr.buf_alloc),
 918                                         le32_to_cpu(pkt->hdr.fwd_cnt));
 919
 920         if (le16_to_cpu(pkt->hdr.type) != VIRTIO_VSOCK_TYPE_STREAM) {
 921                 (void)virtio_transport_reset_no_sock(pkt);
 922                 goto free_pkt;
 923         }
 924
 925         /* The socket must be in connected or bound table
 926          * otherwise send reset back
 927          */
 928         sk = vsock_find_connected_socket(&src, &dst);
 929         if (!sk) {
 930                 sk = vsock_find_bound_socket(&dst);
 931                 if (!sk) {
 932                         (void)virtio_transport_reset_no_sock(pkt);
 933                         goto free_pkt;
 934                 }
 935         }
 936
 937         vsk = vsock_sk(sk);
 938
 939         space_available = virtio_transport_space_update(sk, pkt);
 940
 941         lock_sock(sk);
 942
 943         /* Update CID in case it has changed after a transport reset event */
 944         vsk->local_addr.svm_cid = dst.svm_cid;
 945
 946         if (space_available)
 947                 sk->sk_write_space(sk);
 948
 949         switch (sk->sk_state) {
 950         case VSOCK_SS_LISTEN:
 951                 virtio_transport_recv_listen(sk, pkt);
 952                 virtio_transport_free_pkt(pkt);
 953                 break;
 954         case SS_CONNECTING:
 955                 virtio_transport_recv_connecting(sk, pkt);
 956                 virtio_transport_free_pkt(pkt);
 957                 break;
 958         case SS_CONNECTED:
 959                 virtio_transport_recv_connected(sk, pkt);
 960                 break;
 961         case SS_DISCONNECTING:
 962                 virtio_transport_recv_disconnecting(sk, pkt);
 963                 virtio_transport_free_pkt(pkt);
 964                 break;
 965         default:
 966                 virtio_transport_free_pkt(pkt);
 967                 break;
 968         }
 969         release_sock(sk);
 970
 971         /* Release refcnt obtained when we fetched this socket out of the
 972          * bound or connected list.
 973          */
 974         sock_put(sk);
 975         return;
 976
 977 free_pkt:
 978         virtio_transport_free_pkt(pkt);
 979 }
 980 EXPORT_SYMBOL_GPL(virtio_transport_recv_pkt);
 981
 982 void virtio_transport_free_pkt(struct virtio_vsock_pkt *pkt)
 983 {
 984         kfree(pkt->buf);
 985         kfree(pkt);
 986 }
 987 EXPORT_SYMBOL_GPL(virtio_transport_free_pkt);
 988
 989 MODULE_LICENSE("GPL v2");
 990 MODULE_AUTHOR("Asias He");
 991 MODULE_DESCRIPTION("common code for virtio vsock");