net/vmw_vsock/virtio_transport_common.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * common code for virtio vsock
   4  *
   5  * Copyright (C) 2013-2015 Red Hat, Inc.
   6  * Author: Asias He <asias@redhat.com>
   7  *         Stefan Hajnoczi <stefanha@redhat.com>
   8  */
   9 #include <linux/spinlock.h>
  10 #include <linux/module.h>
  11 #include <linux/sched/signal.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 #include <uapi/linux/vsockmon.h>
  19
  20 #include <net/sock.h>
  21 #include <net/af_vsock.h>
  22
  23 #define CREATE_TRACE_POINTS
  24 #include <trace/events/vsock_virtio_transport_common.h>
  25
  26 /* How long to wait for graceful shutdown of a connection */
  27 #define VSOCK_CLOSE_TIMEOUT (8 * HZ)
  28
  29 static const struct virtio_transport *virtio_transport_get_ops(void)
  30 {
  31         const struct vsock_transport *t = vsock_core_get_transport();
  32
  33         return container_of(t, struct virtio_transport, transport);
  34 }
  35
  36 static struct virtio_vsock_pkt *
  37 virtio_transport_alloc_pkt(struct virtio_vsock_pkt_info *info,
  38                            size_t len,
  39                            u32 src_cid,
  40                            u32 src_port,
  41                            u32 dst_cid,
  42                            u32 dst_port)
  43 {
  44         struct virtio_vsock_pkt *pkt;
  45         int err;
  46
  47         pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
  48         if (!pkt)
  49                 return NULL;
  50
  51         pkt->hdr.type           = cpu_to_le16(info->type);
  52         pkt->hdr.op             = cpu_to_le16(info->op);
  53         pkt->hdr.src_cid        = cpu_to_le64(src_cid);
  54         pkt->hdr.dst_cid        = cpu_to_le64(dst_cid);
  55         pkt->hdr.src_port       = cpu_to_le32(src_port);
  56         pkt->hdr.dst_port       = cpu_to_le32(dst_port);
  57         pkt->hdr.flags          = cpu_to_le32(info->flags);
  58         pkt->len                = len;
  59         pkt->hdr.len            = cpu_to_le32(len);
  60         pkt->reply              = info->reply;
  61         pkt->vsk                = info->vsk;
  62
  63         if (info->msg && len > 0) {
  64                 pkt->buf = kmalloc(len, GFP_KERNEL);
  65                 if (!pkt->buf)
  66                         goto out_pkt;
  67                 err = memcpy_from_msg(pkt->buf, info->msg, len);
  68                 if (err)
  69                         goto out;
  70         }
  71
  72         trace_virtio_transport_alloc_pkt(src_cid, src_port,
  73                                          dst_cid, dst_port,
  74                                          len,
  75                                          info->type,
  76                                          info->op,
  77                                          info->flags);
  78
  79         return pkt;
  80
  81 out:
  82         kfree(pkt->buf);
  83 out_pkt:
  84         kfree(pkt);
  85         return NULL;
  86 }
  87
  88 /* Packet capture */
  89 static struct sk_buff *virtio_transport_build_skb(void *opaque)
  90 {
  91         struct virtio_vsock_pkt *pkt = opaque;
  92         struct af_vsockmon_hdr *hdr;
  93         struct sk_buff *skb;
  94
  95         skb = alloc_skb(sizeof(*hdr) + sizeof(pkt->hdr) + pkt->len,
  96                         GFP_ATOMIC);
  97         if (!skb)
  98                 return NULL;
  99
 100         hdr = skb_put(skb, sizeof(*hdr));
 101
 102         /* pkt->hdr is little-endian so no need to byteswap here */
 103         hdr->src_cid = pkt->hdr.src_cid;
 104         hdr->src_port = pkt->hdr.src_port;
 105         hdr->dst_cid = pkt->hdr.dst_cid;
 106         hdr->dst_port = pkt->hdr.dst_port;
 107
 108         hdr->transport = cpu_to_le16(AF_VSOCK_TRANSPORT_VIRTIO);
 109         hdr->len = cpu_to_le16(sizeof(pkt->hdr));
 110         memset(hdr->reserved, 0, sizeof(hdr->reserved));
 111
 112         switch (le16_to_cpu(pkt->hdr.op)) {
 113         case VIRTIO_VSOCK_OP_REQUEST:
 114         case VIRTIO_VSOCK_OP_RESPONSE:
 115                 hdr->op = cpu_to_le16(AF_VSOCK_OP_CONNECT);
 116                 break;
 117         case VIRTIO_VSOCK_OP_RST:
 118         case VIRTIO_VSOCK_OP_SHUTDOWN:
 119                 hdr->op = cpu_to_le16(AF_VSOCK_OP_DISCONNECT);
 120                 break;
 121         case VIRTIO_VSOCK_OP_RW:
 122                 hdr->op = cpu_to_le16(AF_VSOCK_OP_PAYLOAD);
 123                 break;
 124         case VIRTIO_VSOCK_OP_CREDIT_UPDATE:
 125         case VIRTIO_VSOCK_OP_CREDIT_REQUEST:
 126                 hdr->op = cpu_to_le16(AF_VSOCK_OP_CONTROL);
 127                 break;
 128         default:
 129                 hdr->op = cpu_to_le16(AF_VSOCK_OP_UNKNOWN);
 130                 break;
 131         }
 132
 133         skb_put_data(skb, &pkt->hdr, sizeof(pkt->hdr));
 134
 135         if (pkt->len) {
 136                 skb_put_data(skb, pkt->buf, pkt->len);
 137         }
 138
 139         return skb;
 140 }
 141
 142 void virtio_transport_deliver_tap_pkt(struct virtio_vsock_pkt *pkt)
 143 {
 144         vsock_deliver_tap(virtio_transport_build_skb, pkt);
 145 }
 146 EXPORT_SYMBOL_GPL(virtio_transport_deliver_tap_pkt);
 147
 148 static int virtio_transport_send_pkt_info(struct vsock_sock *vsk,
 149                                           struct virtio_vsock_pkt_info *info)
 150 {
 151         u32 src_cid, src_port, dst_cid, dst_port;
 152         struct virtio_vsock_sock *vvs;
 153         struct virtio_vsock_pkt *pkt;
 154         u32 pkt_len = info->pkt_len;
 155
 156         src_cid = vm_sockets_get_local_cid();
 157         src_port = vsk->local_addr.svm_port;
 158         if (!info->remote_cid) {
 159                 dst_cid = vsk->remote_addr.svm_cid;
 160                 dst_port = vsk->remote_addr.svm_port;
 161         } else {
 162                 dst_cid = info->remote_cid;
 163                 dst_port = info->remote_port;
 164         }
 165
 166         vvs = vsk->trans;
 167
 168         /* we can send less than pkt_len bytes */
 169         if (pkt_len > VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE)
 170                 pkt_len = VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE;
 171
 172         /* virtio_transport_get_credit might return less than pkt_len credit */
 173         pkt_len = virtio_transport_get_credit(vvs, pkt_len);
 174
 175         /* Do not send zero length OP_RW pkt */
 176         if (pkt_len == 0 && info->op == VIRTIO_VSOCK_OP_RW)
 177                 return pkt_len;
 178
 179         pkt = virtio_transport_alloc_pkt(info, pkt_len,
 180                                          src_cid, src_port,
 181                                          dst_cid, dst_port);
 182         if (!pkt) {
 183                 virtio_transport_put_credit(vvs, pkt_len);
 184                 return -ENOMEM;
 185         }
 186
 187         virtio_transport_inc_tx_pkt(vvs, pkt);
 188
 189         return virtio_transport_get_ops()->send_pkt(pkt);
 190 }
 191
 192 static void virtio_transport_inc_rx_pkt(struct virtio_vsock_sock *vvs,
 193                                         struct virtio_vsock_pkt *pkt)
 194 {
 195         vvs->rx_bytes += pkt->len;
 196 }
 197
 198 static void virtio_transport_dec_rx_pkt(struct virtio_vsock_sock *vvs,
 199                                         struct virtio_vsock_pkt *pkt)
 200 {
 201         vvs->rx_bytes -= pkt->len;
 202         vvs->fwd_cnt += pkt->len;
 203 }
 204
 205 void virtio_transport_inc_tx_pkt(struct virtio_vsock_sock *vvs, struct virtio_vsock_pkt *pkt)
 206 {
 207         spin_lock_bh(&vvs->tx_lock);
 208         pkt->hdr.fwd_cnt = cpu_to_le32(vvs->fwd_cnt);
 209         pkt->hdr.buf_alloc = cpu_to_le32(vvs->buf_alloc);
 210         spin_unlock_bh(&vvs->tx_lock);
 211 }
 212 EXPORT_SYMBOL_GPL(virtio_transport_inc_tx_pkt);
 213
 214 u32 virtio_transport_get_credit(struct virtio_vsock_sock *vvs, u32 credit)
 215 {
 216         u32 ret;
 217
 218         spin_lock_bh(&vvs->tx_lock);
 219         ret = vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt);
 220         if (ret > credit)
 221                 ret = credit;
 222         vvs->tx_cnt += ret;
 223         spin_unlock_bh(&vvs->tx_lock);
 224
 225         return ret;
 226 }
 227 EXPORT_SYMBOL_GPL(virtio_transport_get_credit);
 228
 229 void virtio_transport_put_credit(struct virtio_vsock_sock *vvs, u32 credit)
 230 {
 231         spin_lock_bh(&vvs->tx_lock);
 232         vvs->tx_cnt -= credit;
 233         spin_unlock_bh(&vvs->tx_lock);
 234 }
 235 EXPORT_SYMBOL_GPL(virtio_transport_put_credit);
 236
 237 static int virtio_transport_send_credit_update(struct vsock_sock *vsk,
 238                                                int type,
 239                                                struct virtio_vsock_hdr *hdr)
 240 {
 241         struct virtio_vsock_pkt_info info = {
 242                 .op = VIRTIO_VSOCK_OP_CREDIT_UPDATE,
 243                 .type = type,
 244                 .vsk = vsk,
 245         };
 246
 247         return virtio_transport_send_pkt_info(vsk, &info);
 248 }
 249
 250 static ssize_t
 251 virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
 252                                    struct msghdr *msg,
 253                                    size_t len)
 254 {
 255         struct virtio_vsock_sock *vvs = vsk->trans;
 256         struct virtio_vsock_pkt *pkt;
 257         size_t bytes, total = 0;
 258         int err = -EFAULT;
 259
 260         spin_lock_bh(&vvs->rx_lock);
 261         while (total < len && !list_empty(&vvs->rx_queue)) {
 262                 pkt = list_first_entry(&vvs->rx_queue,
 263                                        struct virtio_vsock_pkt, list);
 264
 265                 bytes = len - total;
 266                 if (bytes > pkt->len - pkt->off)
 267                         bytes = pkt->len - pkt->off;
 268
 269                 /* sk_lock is held by caller so no one else can dequeue.
 270                  * Unlock rx_lock since memcpy_to_msg() may sleep.
 271                  */
 272                 spin_unlock_bh(&vvs->rx_lock);
 273
 274                 err = memcpy_to_msg(msg, pkt->buf + pkt->off, bytes);
 275                 if (err)
 276                         goto out;
 277
 278                 spin_lock_bh(&vvs->rx_lock);
 279
 280                 total += bytes;
 281                 pkt->off += bytes;
 282                 if (pkt->off == pkt->len) {
 283                         virtio_transport_dec_rx_pkt(vvs, pkt);
 284                         list_del(&pkt->list);
 285                         virtio_transport_free_pkt(pkt);
 286                 }
 287         }
 288         spin_unlock_bh(&vvs->rx_lock);
 289
 290         /* Send a credit pkt to peer */
 291         virtio_transport_send_credit_update(vsk, VIRTIO_VSOCK_TYPE_STREAM,
 292                                             NULL);
 293
 294         return total;
 295
 296 out:
 297         if (total)
 298                 err = total;
 299         return err;
 300 }
 301
 302 ssize_t
 303 virtio_transport_stream_dequeue(struct vsock_sock *vsk,
 304                                 struct msghdr *msg,
 305                                 size_t len, int flags)
 306 {
 307         if (flags & MSG_PEEK)
 308                 return -EOPNOTSUPP;
 309
 310         return virtio_transport_stream_do_dequeue(vsk, msg, len);
 311 }
 312 EXPORT_SYMBOL_GPL(virtio_transport_stream_dequeue);
 313
 314 int
 315 virtio_transport_dgram_dequeue(struct vsock_sock *vsk,
 316                                struct msghdr *msg,
 317                                size_t len, int flags)
 318 {
 319         return -EOPNOTSUPP;
 320 }
 321 EXPORT_SYMBOL_GPL(virtio_transport_dgram_dequeue);
 322
 323 s64 virtio_transport_stream_has_data(struct vsock_sock *vsk)
 324 {
 325         struct virtio_vsock_sock *vvs = vsk->trans;
 326         s64 bytes;
 327
 328         spin_lock_bh(&vvs->rx_lock);
 329         bytes = vvs->rx_bytes;
 330         spin_unlock_bh(&vvs->rx_lock);
 331
 332         return bytes;
 333 }
 334 EXPORT_SYMBOL_GPL(virtio_transport_stream_has_data);
 335
 336 static s64 virtio_transport_has_space(struct vsock_sock *vsk)
 337 {
 338         struct virtio_vsock_sock *vvs = vsk->trans;
 339         s64 bytes;
 340
 341         bytes = vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt);
 342         if (bytes < 0)
 343                 bytes = 0;
 344
 345         return bytes;
 346 }
 347
 348 s64 virtio_transport_stream_has_space(struct vsock_sock *vsk)
 349 {
 350         struct virtio_vsock_sock *vvs = vsk->trans;
 351         s64 bytes;
 352
 353         spin_lock_bh(&vvs->tx_lock);
 354         bytes = virtio_transport_has_space(vsk);
 355         spin_unlock_bh(&vvs->tx_lock);
 356
 357         return bytes;
 358 }
 359 EXPORT_SYMBOL_GPL(virtio_transport_stream_has_space);
 360
 361 int virtio_transport_do_socket_init(struct vsock_sock *vsk,
 362                                     struct vsock_sock *psk)
 363 {
 364         struct virtio_vsock_sock *vvs;
 365
 366         vvs = kzalloc(sizeof(*vvs), GFP_KERNEL);
 367         if (!vvs)
 368                 return -ENOMEM;
 369
 370         vsk->trans = vvs;
 371         vvs->vsk = vsk;
 372         if (psk) {
 373                 struct virtio_vsock_sock *ptrans = psk->trans;
 374
 375                 vvs->buf_size   = ptrans->buf_size;
 376                 vvs->buf_size_min = ptrans->buf_size_min;
 377                 vvs->buf_size_max = ptrans->buf_size_max;
 378                 vvs->peer_buf_alloc = ptrans->peer_buf_alloc;
 379         } else {
 380                 vvs->buf_size = VIRTIO_VSOCK_DEFAULT_BUF_SIZE;
 381                 vvs->buf_size_min = VIRTIO_VSOCK_DEFAULT_MIN_BUF_SIZE;
 382                 vvs->buf_size_max = VIRTIO_VSOCK_DEFAULT_MAX_BUF_SIZE;
 383         }
 384
 385         vvs->buf_alloc = vvs->buf_size;
 386
 387         spin_lock_init(&vvs->rx_lock);
 388         spin_lock_init(&vvs->tx_lock);
 389         INIT_LIST_HEAD(&vvs->rx_queue);
 390
 391         return 0;
 392 }
 393 EXPORT_SYMBOL_GPL(virtio_transport_do_socket_init);
 394
 395 u64 virtio_transport_get_buffer_size(struct vsock_sock *vsk)
 396 {
 397         struct virtio_vsock_sock *vvs = vsk->trans;
 398
 399         return vvs->buf_size;
 400 }
 401 EXPORT_SYMBOL_GPL(virtio_transport_get_buffer_size);
 402
 403 u64 virtio_transport_get_min_buffer_size(struct vsock_sock *vsk)
 404 {
 405         struct virtio_vsock_sock *vvs = vsk->trans;
 406
 407         return vvs->buf_size_min;
 408 }
 409 EXPORT_SYMBOL_GPL(virtio_transport_get_min_buffer_size);
 410
 411 u64 virtio_transport_get_max_buffer_size(struct vsock_sock *vsk)
 412 {
 413         struct virtio_vsock_sock *vvs = vsk->trans;
 414
 415         return vvs->buf_size_max;
 416 }
 417 EXPORT_SYMBOL_GPL(virtio_transport_get_max_buffer_size);
 418
 419 void virtio_transport_set_buffer_size(struct vsock_sock *vsk, u64 val)
 420 {
 421         struct virtio_vsock_sock *vvs = vsk->trans;
 422
 423         if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
 424                 val = VIRTIO_VSOCK_MAX_BUF_SIZE;
 425         if (val < vvs->buf_size_min)
 426                 vvs->buf_size_min = val;
 427         if (val > vvs->buf_size_max)
 428                 vvs->buf_size_max = val;
 429         vvs->buf_size = val;
 430         vvs->buf_alloc = val;
 431 }
 432 EXPORT_SYMBOL_GPL(virtio_transport_set_buffer_size);
 433
 434 void virtio_transport_set_min_buffer_size(struct vsock_sock *vsk, u64 val)
 435 {
 436         struct virtio_vsock_sock *vvs = vsk->trans;
 437
 438         if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
 439                 val = VIRTIO_VSOCK_MAX_BUF_SIZE;
 440         if (val > vvs->buf_size)
 441                 vvs->buf_size = val;
 442         vvs->buf_size_min = val;
 443 }
 444 EXPORT_SYMBOL_GPL(virtio_transport_set_min_buffer_size);
 445
 446 void virtio_transport_set_max_buffer_size(struct vsock_sock *vsk, u64 val)
 447 {
 448         struct virtio_vsock_sock *vvs = vsk->trans;
 449
 450         if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
 451                 val = VIRTIO_VSOCK_MAX_BUF_SIZE;
 452         if (val < vvs->buf_size)
 453                 vvs->buf_size = val;
 454         vvs->buf_size_max = val;
 455 }
 456 EXPORT_SYMBOL_GPL(virtio_transport_set_max_buffer_size);
 457
 458 int
 459 virtio_transport_notify_poll_in(struct vsock_sock *vsk,
 460                                 size_t target,
 461                                 bool *data_ready_now)
 462 {
 463         if (vsock_stream_has_data(vsk))
 464                 *data_ready_now = true;
 465         else
 466                 *data_ready_now = false;
 467
 468         return 0;
 469 }
 470 EXPORT_SYMBOL_GPL(virtio_transport_notify_poll_in);
 471
 472 int
 473 virtio_transport_notify_poll_out(struct vsock_sock *vsk,
 474                                  size_t target,
 475                                  bool *space_avail_now)
 476 {
 477         s64 free_space;
 478
 479         free_space = vsock_stream_has_space(vsk);
 480         if (free_space > 0)
 481                 *space_avail_now = true;
 482         else if (free_space == 0)
 483                 *space_avail_now = false;
 484
 485         return 0;
 486 }
 487 EXPORT_SYMBOL_GPL(virtio_transport_notify_poll_out);
 488
 489 int virtio_transport_notify_recv_init(struct vsock_sock *vsk,
 490         size_t target, struct vsock_transport_recv_notify_data *data)
 491 {
 492         return 0;
 493 }
 494 EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_init);
 495
 496 int virtio_transport_notify_recv_pre_block(struct vsock_sock *vsk,
 497         size_t target, struct vsock_transport_recv_notify_data *data)
 498 {
 499         return 0;
 500 }
 501 EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_pre_block);
 502
 503 int virtio_transport_notify_recv_pre_dequeue(struct vsock_sock *vsk,
 504         size_t target, struct vsock_transport_recv_notify_data *data)
 505 {
 506         return 0;
 507 }
 508 EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_pre_dequeue);
 509
 510 int virtio_transport_notify_recv_post_dequeue(struct vsock_sock *vsk,
 511         size_t target, ssize_t copied, bool data_read,
 512         struct vsock_transport_recv_notify_data *data)
 513 {
 514         return 0;
 515 }
 516 EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_post_dequeue);
 517
 518 int virtio_transport_notify_send_init(struct vsock_sock *vsk,
 519         struct vsock_transport_send_notify_data *data)
 520 {
 521         return 0;
 522 }
 523 EXPORT_SYMBOL_GPL(virtio_transport_notify_send_init);
 524
 525 int virtio_transport_notify_send_pre_block(struct vsock_sock *vsk,
 526         struct vsock_transport_send_notify_data *data)
 527 {
 528         return 0;
 529 }
 530 EXPORT_SYMBOL_GPL(virtio_transport_notify_send_pre_block);
 531
 532 int virtio_transport_notify_send_pre_enqueue(struct vsock_sock *vsk,
 533         struct vsock_transport_send_notify_data *data)
 534 {
 535         return 0;
 536 }
 537 EXPORT_SYMBOL_GPL(virtio_transport_notify_send_pre_enqueue);
 538
 539 int virtio_transport_notify_send_post_enqueue(struct vsock_sock *vsk,
 540         ssize_t written, struct vsock_transport_send_notify_data *data)
 541 {
 542         return 0;
 543 }
 544 EXPORT_SYMBOL_GPL(virtio_transport_notify_send_post_enqueue);
 545
 546 u64 virtio_transport_stream_rcvhiwat(struct vsock_sock *vsk)
 547 {
 548         struct virtio_vsock_sock *vvs = vsk->trans;
 549
 550         return vvs->buf_size;
 551 }
 552 EXPORT_SYMBOL_GPL(virtio_transport_stream_rcvhiwat);
 553
 554 bool virtio_transport_stream_is_active(struct vsock_sock *vsk)
 555 {
 556         return true;
 557 }
 558 EXPORT_SYMBOL_GPL(virtio_transport_stream_is_active);
 559
 560 bool virtio_transport_stream_allow(u32 cid, u32 port)
 561 {
 562         return true;
 563 }
 564 EXPORT_SYMBOL_GPL(virtio_transport_stream_allow);
 565
 566 int virtio_transport_dgram_bind(struct vsock_sock *vsk,
 567                                 struct sockaddr_vm *addr)
 568 {
 569         return -EOPNOTSUPP;
 570 }
 571 EXPORT_SYMBOL_GPL(virtio_transport_dgram_bind);
 572
 573 bool virtio_transport_dgram_allow(u32 cid, u32 port)
 574 {
 575         return false;
 576 }
 577 EXPORT_SYMBOL_GPL(virtio_transport_dgram_allow);
 578
 579 int virtio_transport_connect(struct vsock_sock *vsk)
 580 {
 581         struct virtio_vsock_pkt_info info = {
 582                 .op = VIRTIO_VSOCK_OP_REQUEST,
 583                 .type = VIRTIO_VSOCK_TYPE_STREAM,
 584                 .vsk = vsk,
 585         };
 586
 587         return virtio_transport_send_pkt_info(vsk, &info);
 588 }
 589 EXPORT_SYMBOL_GPL(virtio_transport_connect);
 590
 591 int virtio_transport_shutdown(struct vsock_sock *vsk, int mode)
 592 {
 593         struct virtio_vsock_pkt_info info = {
 594                 .op = VIRTIO_VSOCK_OP_SHUTDOWN,
 595                 .type = VIRTIO_VSOCK_TYPE_STREAM,
 596                 .flags = (mode & RCV_SHUTDOWN ?
 597                           VIRTIO_VSOCK_SHUTDOWN_RCV : 0) |
 598                          (mode & SEND_SHUTDOWN ?
 599                           VIRTIO_VSOCK_SHUTDOWN_SEND : 0),
 600                 .vsk = vsk,
 601         };
 602
 603         return virtio_transport_send_pkt_info(vsk, &info);
 604 }
 605 EXPORT_SYMBOL_GPL(virtio_transport_shutdown);
 606
 607 int
 608 virtio_transport_dgram_enqueue(struct vsock_sock *vsk,
 609                                struct sockaddr_vm *remote_addr,
 610                                struct msghdr *msg,
 611                                size_t dgram_len)
 612 {
 613         return -EOPNOTSUPP;
 614 }
 615 EXPORT_SYMBOL_GPL(virtio_transport_dgram_enqueue);
 616
 617 ssize_t
 618 virtio_transport_stream_enqueue(struct vsock_sock *vsk,
 619                                 struct msghdr *msg,
 620                                 size_t len)
 621 {
 622         struct virtio_vsock_pkt_info info = {
 623                 .op = VIRTIO_VSOCK_OP_RW,
 624                 .type = VIRTIO_VSOCK_TYPE_STREAM,
 625                 .msg = msg,
 626                 .pkt_len = len,
 627                 .vsk = vsk,
 628         };
 629
 630         return virtio_transport_send_pkt_info(vsk, &info);
 631 }
 632 EXPORT_SYMBOL_GPL(virtio_transport_stream_enqueue);
 633
 634 void virtio_transport_destruct(struct vsock_sock *vsk)
 635 {
 636         struct virtio_vsock_sock *vvs = vsk->trans;
 637
 638         kfree(vvs);
 639 }
 640 EXPORT_SYMBOL_GPL(virtio_transport_destruct);
 641
 642 static int virtio_transport_reset(struct vsock_sock *vsk,
 643                                   struct virtio_vsock_pkt *pkt)
 644 {
 645         struct virtio_vsock_pkt_info info = {
 646                 .op = VIRTIO_VSOCK_OP_RST,
 647                 .type = VIRTIO_VSOCK_TYPE_STREAM,
 648                 .reply = !!pkt,
 649                 .vsk = vsk,
 650         };
 651
 652         /* Send RST only if the original pkt is not a RST pkt */
 653         if (pkt && le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
 654                 return 0;
 655
 656         return virtio_transport_send_pkt_info(vsk, &info);
 657 }
 658
 659 /* Normally packets are associated with a socket.  There may be no socket if an
 660  * attempt was made to connect to a socket that does not exist.
 661  */
 662 static int virtio_transport_reset_no_sock(struct virtio_vsock_pkt *pkt)
 663 {
 664         const struct virtio_transport *t;
 665         struct virtio_vsock_pkt *reply;
 666         struct virtio_vsock_pkt_info info = {
 667                 .op = VIRTIO_VSOCK_OP_RST,
 668                 .type = le16_to_cpu(pkt->hdr.type),
 669                 .reply = true,
 670         };
 671
 672         /* Send RST only if the original pkt is not a RST pkt */
 673         if (le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
 674                 return 0;
 675
 676         reply = virtio_transport_alloc_pkt(&info, 0,
 677                                            le64_to_cpu(pkt->hdr.dst_cid),
 678                                            le32_to_cpu(pkt->hdr.dst_port),
 679                                            le64_to_cpu(pkt->hdr.src_cid),
 680                                            le32_to_cpu(pkt->hdr.src_port));
 681         if (!reply)
 682                 return -ENOMEM;
 683
 684         t = virtio_transport_get_ops();
 685         if (!t) {
 686                 virtio_transport_free_pkt(reply);
 687                 return -ENOTCONN;
 688         }
 689
 690         return t->send_pkt(reply);
 691 }
 692
 693 static void virtio_transport_wait_close(struct sock *sk, long timeout)
 694 {
 695         if (timeout) {
 696                 DEFINE_WAIT_FUNC(wait, woken_wake_function);
 697
 698                 add_wait_queue(sk_sleep(sk), &wait);
 699
 700                 do {
 701                         if (sk_wait_event(sk, &timeout,
 702                                           sock_flag(sk, SOCK_DONE), &wait))
 703                                 break;
 704                 } while (!signal_pending(current) && timeout);
 705
 706                 remove_wait_queue(sk_sleep(sk), &wait);
 707         }
 708 }
 709
 710 static void virtio_transport_do_close(struct vsock_sock *vsk,
 711                                       bool cancel_timeout)
 712 {
 713         struct sock *sk = sk_vsock(vsk);
 714
 715         sock_set_flag(sk, SOCK_DONE);
 716         vsk->peer_shutdown = SHUTDOWN_MASK;
 717         if (vsock_stream_has_data(vsk) <= 0)
 718                 sk->sk_state = TCP_CLOSING;
 719         sk->sk_state_change(sk);
 720
 721         if (vsk->close_work_scheduled &&
 722             (!cancel_timeout || cancel_delayed_work(&vsk->close_work))) {
 723                 vsk->close_work_scheduled = false;
 724
 725                 vsock_remove_sock(vsk);
 726
 727                 /* Release refcnt obtained when we scheduled the timeout */
 728                 sock_put(sk);
 729         }
 730 }
 731
 732 static void virtio_transport_close_timeout(struct work_struct *work)
 733 {
 734         struct vsock_sock *vsk =
 735                 container_of(work, struct vsock_sock, close_work.work);
 736         struct sock *sk = sk_vsock(vsk);
 737
 738         sock_hold(sk);
 739         lock_sock(sk);
 740
 741         if (!sock_flag(sk, SOCK_DONE)) {
 742                 (void)virtio_transport_reset(vsk, NULL);
 743
 744                 virtio_transport_do_close(vsk, false);
 745         }
 746
 747         vsk->close_work_scheduled = false;
 748
 749         release_sock(sk);
 750         sock_put(sk);
 751 }
 752
 753 /* User context, vsk->sk is locked */
 754 static bool virtio_transport_close(struct vsock_sock *vsk)
 755 {
 756         struct sock *sk = &vsk->sk;
 757
 758         if (!(sk->sk_state == TCP_ESTABLISHED ||
 759               sk->sk_state == TCP_CLOSING))
 760                 return true;
 761
 762         /* Already received SHUTDOWN from peer, reply with RST */
 763         if ((vsk->peer_shutdown & SHUTDOWN_MASK) == SHUTDOWN_MASK) {
 764                 (void)virtio_transport_reset(vsk, NULL);
 765                 return true;
 766         }
 767
 768         if ((sk->sk_shutdown & SHUTDOWN_MASK) != SHUTDOWN_MASK)
 769                 (void)virtio_transport_shutdown(vsk, SHUTDOWN_MASK);
 770
 771         if (sock_flag(sk, SOCK_LINGER) && !(current->flags & PF_EXITING))
 772                 virtio_transport_wait_close(sk, sk->sk_lingertime);
 773
 774         if (sock_flag(sk, SOCK_DONE)) {
 775                 return true;
 776         }
 777
 778         sock_hold(sk);
 779         INIT_DELAYED_WORK(&vsk->close_work,
 780                           virtio_transport_close_timeout);
 781         vsk->close_work_scheduled = true;
 782         schedule_delayed_work(&vsk->close_work, VSOCK_CLOSE_TIMEOUT);
 783         return false;
 784 }
 785
 786 void virtio_transport_release(struct vsock_sock *vsk)
 787 {
 788         struct virtio_vsock_sock *vvs = vsk->trans;
 789         struct virtio_vsock_pkt *pkt, *tmp;
 790         struct sock *sk = &vsk->sk;
 791         bool remove_sock = true;
 792
 793         lock_sock(sk);
 794         if (sk->sk_type == SOCK_STREAM)
 795                 remove_sock = virtio_transport_close(vsk);
 796
 797         list_for_each_entry_safe(pkt, tmp, &vvs->rx_queue, list) {
 798                 list_del(&pkt->list);
 799                 virtio_transport_free_pkt(pkt);
 800         }
 801         release_sock(sk);
 802
 803         if (remove_sock)
 804                 vsock_remove_sock(vsk);
 805 }
 806 EXPORT_SYMBOL_GPL(virtio_transport_release);
 807
 808 static int
 809 virtio_transport_recv_connecting(struct sock *sk,
 810                                  struct virtio_vsock_pkt *pkt)
 811 {
 812         struct vsock_sock *vsk = vsock_sk(sk);
 813         int err;
 814         int skerr;
 815
 816         switch (le16_to_cpu(pkt->hdr.op)) {
 817         case VIRTIO_VSOCK_OP_RESPONSE:
 818                 sk->sk_state = TCP_ESTABLISHED;
 819                 sk->sk_socket->state = SS_CONNECTED;
 820                 vsock_insert_connected(vsk);
 821                 sk->sk_state_change(sk);
 822                 break;
 823         case VIRTIO_VSOCK_OP_INVALID:
 824                 break;
 825         case VIRTIO_VSOCK_OP_RST:
 826                 skerr = ECONNRESET;
 827                 err = 0;
 828                 goto destroy;
 829         default:
 830                 skerr = EPROTO;
 831                 err = -EINVAL;
 832                 goto destroy;
 833         }
 834         return 0;
 835
 836 destroy:
 837         virtio_transport_reset(vsk, pkt);
 838         sk->sk_state = TCP_CLOSE;
 839         sk->sk_err = skerr;
 840         sk->sk_error_report(sk);
 841         return err;
 842 }
 843
 844 static int
 845 virtio_transport_recv_connected(struct sock *sk,
 846                                 struct virtio_vsock_pkt *pkt)
 847 {
 848         struct vsock_sock *vsk = vsock_sk(sk);
 849         struct virtio_vsock_sock *vvs = vsk->trans;
 850         int err = 0;
 851
 852         switch (le16_to_cpu(pkt->hdr.op)) {
 853         case VIRTIO_VSOCK_OP_RW:
 854                 pkt->len = le32_to_cpu(pkt->hdr.len);
 855                 pkt->off = 0;
 856
 857                 spin_lock_bh(&vvs->rx_lock);
 858                 virtio_transport_inc_rx_pkt(vvs, pkt);
 859                 list_add_tail(&pkt->list, &vvs->rx_queue);
 860                 spin_unlock_bh(&vvs->rx_lock);
 861
 862                 sk->sk_data_ready(sk);
 863                 return err;
 864         case VIRTIO_VSOCK_OP_CREDIT_UPDATE:
 865                 sk->sk_write_space(sk);
 866                 break;
 867         case VIRTIO_VSOCK_OP_SHUTDOWN:
 868                 if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SHUTDOWN_RCV)
 869                         vsk->peer_shutdown |= RCV_SHUTDOWN;
 870                 if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SHUTDOWN_SEND)
 871                         vsk->peer_shutdown |= SEND_SHUTDOWN;
 872                 if (vsk->peer_shutdown == SHUTDOWN_MASK &&
 873                     vsock_stream_has_data(vsk) <= 0) {
 874                         sock_set_flag(sk, SOCK_DONE);
 875                         sk->sk_state = TCP_CLOSING;
 876                 }
 877                 if (le32_to_cpu(pkt->hdr.flags))
 878                         sk->sk_state_change(sk);
 879                 break;
 880         case VIRTIO_VSOCK_OP_RST:
 881                 virtio_transport_do_close(vsk, true);
 882                 break;
 883         default:
 884                 err = -EINVAL;
 885                 break;
 886         }
 887
 888         virtio_transport_free_pkt(pkt);
 889         return err;
 890 }
 891
 892 static void
 893 virtio_transport_recv_disconnecting(struct sock *sk,
 894                                     struct virtio_vsock_pkt *pkt)
 895 {
 896         struct vsock_sock *vsk = vsock_sk(sk);
 897
 898         if (le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
 899                 virtio_transport_do_close(vsk, true);
 900 }
 901
 902 static int
 903 virtio_transport_send_response(struct vsock_sock *vsk,
 904                                struct virtio_vsock_pkt *pkt)
 905 {
 906         struct virtio_vsock_pkt_info info = {
 907                 .op = VIRTIO_VSOCK_OP_RESPONSE,
 908                 .type = VIRTIO_VSOCK_TYPE_STREAM,
 909                 .remote_cid = le64_to_cpu(pkt->hdr.src_cid),
 910                 .remote_port = le32_to_cpu(pkt->hdr.src_port),
 911                 .reply = true,
 912                 .vsk = vsk,
 913         };
 914
 915         return virtio_transport_send_pkt_info(vsk, &info);
 916 }
 917
 918 /* Handle server socket */
 919 static int
 920 virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt)
 921 {
 922         struct vsock_sock *vsk = vsock_sk(sk);
 923         struct vsock_sock *vchild;
 924         struct sock *child;
 925
 926         if (le16_to_cpu(pkt->hdr.op) != VIRTIO_VSOCK_OP_REQUEST) {
 927                 virtio_transport_reset(vsk, pkt);
 928                 return -EINVAL;
 929         }
 930
 931         if (sk_acceptq_is_full(sk)) {
 932                 virtio_transport_reset(vsk, pkt);
 933                 return -ENOMEM;
 934         }
 935
 936         child = __vsock_create(sock_net(sk), NULL, sk, GFP_KERNEL,
 937                                sk->sk_type, 0);
 938         if (!child) {
 939                 virtio_transport_reset(vsk, pkt);
 940                 return -ENOMEM;
 941         }
 942
 943         sk->sk_ack_backlog++;
 944
 945         lock_sock_nested(child, SINGLE_DEPTH_NESTING);
 946
 947         child->sk_state = TCP_ESTABLISHED;
 948
 949         vchild = vsock_sk(child);
 950         vsock_addr_init(&vchild->local_addr, le64_to_cpu(pkt->hdr.dst_cid),
 951                         le32_to_cpu(pkt->hdr.dst_port));
 952         vsock_addr_init(&vchild->remote_addr, le64_to_cpu(pkt->hdr.src_cid),
 953                         le32_to_cpu(pkt->hdr.src_port));
 954
 955         vsock_insert_connected(vchild);
 956         vsock_enqueue_accept(sk, child);
 957         virtio_transport_send_response(vchild, pkt);
 958
 959         release_sock(child);
 960
 961         sk->sk_data_ready(sk);
 962         return 0;
 963 }
 964
 965 static bool virtio_transport_space_update(struct sock *sk,
 966                                           struct virtio_vsock_pkt *pkt)
 967 {
 968         struct vsock_sock *vsk = vsock_sk(sk);
 969         struct virtio_vsock_sock *vvs = vsk->trans;
 970         bool space_available;
 971
 972         /* buf_alloc and fwd_cnt is always included in the hdr */
 973         spin_lock_bh(&vvs->tx_lock);
 974         vvs->peer_buf_alloc = le32_to_cpu(pkt->hdr.buf_alloc);
 975         vvs->peer_fwd_cnt = le32_to_cpu(pkt->hdr.fwd_cnt);
 976         space_available = virtio_transport_has_space(vsk);
 977         spin_unlock_bh(&vvs->tx_lock);
 978         return space_available;
 979 }
 980
 981 /* We are under the virtio-vsock's vsock->rx_lock or vhost-vsock's vq->mutex
 982  * lock.
 983  */
 984 void virtio_transport_recv_pkt(struct virtio_vsock_pkt *pkt)
 985 {
 986         struct sockaddr_vm src, dst;
 987         struct vsock_sock *vsk;
 988         struct sock *sk;
 989         bool space_available;
 990
 991         vsock_addr_init(&src, le64_to_cpu(pkt->hdr.src_cid),
 992                         le32_to_cpu(pkt->hdr.src_port));
 993         vsock_addr_init(&dst, le64_to_cpu(pkt->hdr.dst_cid),
 994                         le32_to_cpu(pkt->hdr.dst_port));
 995
 996         trace_virtio_transport_recv_pkt(src.svm_cid, src.svm_port,
 997                                         dst.svm_cid, dst.svm_port,
 998                                         le32_to_cpu(pkt->hdr.len),
 999                                         le16_to_cpu(pkt->hdr.type),
1000                                         le16_to_cpu(pkt->hdr.op),
1001                                         le32_to_cpu(pkt->hdr.flags),
1002                                         le32_to_cpu(pkt->hdr.buf_alloc),
1003                                         le32_to_cpu(pkt->hdr.fwd_cnt));
1004
1005         if (le16_to_cpu(pkt->hdr.type) != VIRTIO_VSOCK_TYPE_STREAM) {
1006                 (void)virtio_transport_reset_no_sock(pkt);
1007                 goto free_pkt;
1008         }
1009
1010         /* The socket must be in connected or bound table
1011          * otherwise send reset back
1012          */
1013         sk = vsock_find_connected_socket(&src, &dst);
1014         if (!sk) {
1015                 sk = vsock_find_bound_socket(&dst);
1016                 if (!sk) {
1017                         (void)virtio_transport_reset_no_sock(pkt);
1018                         goto free_pkt;
1019                 }
1020         }
1021
1022         vsk = vsock_sk(sk);
1023
1024         space_available = virtio_transport_space_update(sk, pkt);
1025
1026         lock_sock(sk);
1027
1028         /* Update CID in case it has changed after a transport reset event */
1029         vsk->local_addr.svm_cid = dst.svm_cid;
1030
1031         if (space_available)
1032                 sk->sk_write_space(sk);
1033
1034         switch (sk->sk_state) {
1035         case TCP_LISTEN:
1036                 virtio_transport_recv_listen(sk, pkt);
1037                 virtio_transport_free_pkt(pkt);
1038                 break;
1039         case TCP_SYN_SENT:
1040                 virtio_transport_recv_connecting(sk, pkt);
1041                 virtio_transport_free_pkt(pkt);
1042                 break;
1043         case TCP_ESTABLISHED:
1044                 virtio_transport_recv_connected(sk, pkt);
1045                 break;
1046         case TCP_CLOSING:
1047                 virtio_transport_recv_disconnecting(sk, pkt);
1048                 virtio_transport_free_pkt(pkt);
1049                 break;
1050         default:
1051                 virtio_transport_free_pkt(pkt);
1052                 break;
1053         }
1054         release_sock(sk);
1055
1056         /* Release refcnt obtained when we fetched this socket out of the
1057          * bound or connected list.
1058          */
1059         sock_put(sk);
1060         return;
1061
1062 free_pkt:
1063         virtio_transport_free_pkt(pkt);
1064 }
1065 EXPORT_SYMBOL_GPL(virtio_transport_recv_pkt);
1066
1067 void virtio_transport_free_pkt(struct virtio_vsock_pkt *pkt)
1068 {
1069         kfree(pkt->buf);
1070         kfree(pkt);
1071 }
1072 EXPORT_SYMBOL_GPL(virtio_transport_free_pkt);
1073
1074 MODULE_LICENSE("GPL v2");
1075 MODULE_AUTHOR("Asias He");
1076 MODULE_DESCRIPTION("common code for virtio vsock");