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