1 /* 2 * Hyper-V transport for vsock 3 * 4 * Hyper-V Sockets supplies a byte-stream based communication mechanism 5 * between the host and the VM. This driver implements the necessary 6 * support in the VM by introducing the new vsock transport. 7 * 8 * Copyright (c) 2017, Microsoft Corporation. 9 * 10 * This program is free software; you can redistribute it and/or modify it 11 * under the terms and conditions of the GNU General Public License, 12 * version 2, as published by the Free Software Foundation. 13 * 14 * This program is distributed in the hope it will be useful, but WITHOUT 15 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 16 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 17 * more details. 18 * 19 */ 20 #include <linux/module.h> 21 #include <linux/vmalloc.h> 22 #include <linux/hyperv.h> 23 #include <net/sock.h> 24 #include <net/af_vsock.h> 25 26 /* The host side's design of the feature requires 6 exact 4KB pages for 27 * recv/send rings respectively -- this is suboptimal considering memory 28 * consumption, however unluckily we have to live with it, before the 29 * host comes up with a better design in the future. 30 */ 31 #define PAGE_SIZE_4K 4096 32 #define RINGBUFFER_HVS_RCV_SIZE (PAGE_SIZE_4K * 6) 33 #define RINGBUFFER_HVS_SND_SIZE (PAGE_SIZE_4K * 6) 34 35 /* The MTU is 16KB per the host side's design */ 36 #define HVS_MTU_SIZE (1024 * 16) 37 38 struct vmpipe_proto_header { 39 u32 pkt_type; 40 u32 data_size; 41 }; 42 43 /* For recv, we use the VMBus in-place packet iterator APIs to directly copy 44 * data from the ringbuffer into the userspace buffer. 45 */ 46 struct hvs_recv_buf { 47 /* The header before the payload data */ 48 struct vmpipe_proto_header hdr; 49 50 /* The payload */ 51 u8 data[HVS_MTU_SIZE]; 52 }; 53 54 /* We can send up to HVS_MTU_SIZE bytes of payload to the host, but let's use 55 * a small size, i.e. HVS_SEND_BUF_SIZE, to minimize the dynamically-allocated 56 * buffer, because tests show there is no significant performance difference. 57 * 58 * Note: the buffer can be eliminated in the future when we add new VMBus 59 * ringbuffer APIs that allow us to directly copy data from userspace buffer 60 * to VMBus ringbuffer. 61 */ 62 #define HVS_SEND_BUF_SIZE (PAGE_SIZE_4K - sizeof(struct vmpipe_proto_header)) 63 64 struct hvs_send_buf { 65 /* The header before the payload data */ 66 struct vmpipe_proto_header hdr; 67 68 /* The payload */ 69 u8 data[HVS_SEND_BUF_SIZE]; 70 }; 71 72 #define HVS_HEADER_LEN (sizeof(struct vmpacket_descriptor) + \ 73 sizeof(struct vmpipe_proto_header)) 74 75 /* See 'prev_indices' in hv_ringbuffer_read(), hv_ringbuffer_write(), and 76 * __hv_pkt_iter_next(). 77 */ 78 #define VMBUS_PKT_TRAILER_SIZE (sizeof(u64)) 79 80 #define HVS_PKT_LEN(payload_len) (HVS_HEADER_LEN + \ 81 ALIGN((payload_len), 8) + \ 82 VMBUS_PKT_TRAILER_SIZE) 83 84 union hvs_service_id { 85 uuid_le srv_id; 86 87 struct { 88 unsigned int svm_port; 89 unsigned char b[sizeof(uuid_le) - sizeof(unsigned int)]; 90 }; 91 }; 92 93 /* Per-socket state (accessed via vsk->trans) */ 94 struct hvsock { 95 struct vsock_sock *vsk; 96 97 uuid_le vm_srv_id; 98 uuid_le host_srv_id; 99 100 struct vmbus_channel *chan; 101 struct vmpacket_descriptor *recv_desc; 102 103 /* The length of the payload not delivered to userland yet */ 104 u32 recv_data_len; 105 /* The offset of the payload */ 106 u32 recv_data_off; 107 108 /* Have we sent the zero-length packet (FIN)? */ 109 bool fin_sent; 110 }; 111 112 /* In the VM, we support Hyper-V Sockets with AF_VSOCK, and the endpoint is 113 * <cid, port> (see struct sockaddr_vm). Note: cid is not really used here: 114 * when we write apps to connect to the host, we can only use VMADDR_CID_ANY 115 * or VMADDR_CID_HOST (both are equivalent) as the remote cid, and when we 116 * write apps to bind() & listen() in the VM, we can only use VMADDR_CID_ANY 117 * as the local cid. 118 * 119 * On the host, Hyper-V Sockets are supported by Winsock AF_HYPERV: 120 * https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/user- 121 * guide/make-integration-service, and the endpoint is <VmID, ServiceId> with 122 * the below sockaddr: 123 * 124 * struct SOCKADDR_HV 125 * { 126 * ADDRESS_FAMILY Family; 127 * USHORT Reserved; 128 * GUID VmId; 129 * GUID ServiceId; 130 * }; 131 * Note: VmID is not used by Linux VM and actually it isn't transmitted via 132 * VMBus, because here it's obvious the host and the VM can easily identify 133 * each other. Though the VmID is useful on the host, especially in the case 134 * of Windows container, Linux VM doesn't need it at all. 135 * 136 * To make use of the AF_VSOCK infrastructure in Linux VM, we have to limit 137 * the available GUID space of SOCKADDR_HV so that we can create a mapping 138 * between AF_VSOCK port and SOCKADDR_HV Service GUID. The rule of writing 139 * Hyper-V Sockets apps on the host and in Linux VM is: 140 * 141 **************************************************************************** 142 * The only valid Service GUIDs, from the perspectives of both the host and * 143 * Linux VM, that can be connected by the other end, must conform to this * 144 * format: <port>-facb-11e6-bd58-64006a7986d3, and the "port" must be in * 145 * this range [0, 0x7FFFFFFF]. * 146 **************************************************************************** 147 * 148 * When we write apps on the host to connect(), the GUID ServiceID is used. 149 * When we write apps in Linux VM to connect(), we only need to specify the 150 * port and the driver will form the GUID and use that to request the host. 151 * 152 * From the perspective of Linux VM: 153 * 1. the local ephemeral port (i.e. the local auto-bound port when we call 154 * connect() without explicit bind()) is generated by __vsock_bind_stream(), 155 * and the range is [1024, 0xFFFFFFFF). 156 * 2. the remote ephemeral port (i.e. the auto-generated remote port for 157 * a connect request initiated by the host's connect()) is generated by 158 * hvs_remote_addr_init() and the range is [0x80000000, 0xFFFFFFFF). 159 */ 160 161 #define MAX_LISTEN_PORT ((u32)0x7FFFFFFF) 162 #define MAX_VM_LISTEN_PORT MAX_LISTEN_PORT 163 #define MAX_HOST_LISTEN_PORT MAX_LISTEN_PORT 164 #define MIN_HOST_EPHEMERAL_PORT (MAX_HOST_LISTEN_PORT + 1) 165 166 /* 00000000-facb-11e6-bd58-64006a7986d3 */ 167 static const uuid_le srv_id_template = 168 UUID_LE(0x00000000, 0xfacb, 0x11e6, 0xbd, 0x58, 169 0x64, 0x00, 0x6a, 0x79, 0x86, 0xd3); 170 171 static bool is_valid_srv_id(const uuid_le *id) 172 { 173 return !memcmp(&id->b[4], &srv_id_template.b[4], sizeof(uuid_le) - 4); 174 } 175 176 static unsigned int get_port_by_srv_id(const uuid_le *svr_id) 177 { 178 return *((unsigned int *)svr_id); 179 } 180 181 static void hvs_addr_init(struct sockaddr_vm *addr, const uuid_le *svr_id) 182 { 183 unsigned int port = get_port_by_srv_id(svr_id); 184 185 vsock_addr_init(addr, VMADDR_CID_ANY, port); 186 } 187 188 static void hvs_remote_addr_init(struct sockaddr_vm *remote, 189 struct sockaddr_vm *local) 190 { 191 static u32 host_ephemeral_port = MIN_HOST_EPHEMERAL_PORT; 192 struct sock *sk; 193 194 vsock_addr_init(remote, VMADDR_CID_ANY, VMADDR_PORT_ANY); 195 196 while (1) { 197 /* Wrap around ? */ 198 if (host_ephemeral_port < MIN_HOST_EPHEMERAL_PORT || 199 host_ephemeral_port == VMADDR_PORT_ANY) 200 host_ephemeral_port = MIN_HOST_EPHEMERAL_PORT; 201 202 remote->svm_port = host_ephemeral_port++; 203 204 sk = vsock_find_connected_socket(remote, local); 205 if (!sk) { 206 /* Found an available ephemeral port */ 207 return; 208 } 209 210 /* Release refcnt got in vsock_find_connected_socket */ 211 sock_put(sk); 212 } 213 } 214 215 static void hvs_set_channel_pending_send_size(struct vmbus_channel *chan) 216 { 217 set_channel_pending_send_size(chan, 218 HVS_PKT_LEN(HVS_SEND_BUF_SIZE)); 219 220 /* See hvs_stream_has_space(): we must make sure the host has seen 221 * the new pending send size, before we can re-check the writable 222 * bytes. 223 */ 224 virt_mb(); 225 } 226 227 static void hvs_clear_channel_pending_send_size(struct vmbus_channel *chan) 228 { 229 set_channel_pending_send_size(chan, 0); 230 231 /* Ditto */ 232 virt_mb(); 233 } 234 235 static bool hvs_channel_readable(struct vmbus_channel *chan) 236 { 237 u32 readable = hv_get_bytes_to_read(&chan->inbound); 238 239 /* 0-size payload means FIN */ 240 return readable >= HVS_PKT_LEN(0); 241 } 242 243 static int hvs_channel_readable_payload(struct vmbus_channel *chan) 244 { 245 u32 readable = hv_get_bytes_to_read(&chan->inbound); 246 247 if (readable > HVS_PKT_LEN(0)) { 248 /* At least we have 1 byte to read. We don't need to return 249 * the exact readable bytes: see vsock_stream_recvmsg() -> 250 * vsock_stream_has_data(). 251 */ 252 return 1; 253 } 254 255 if (readable == HVS_PKT_LEN(0)) { 256 /* 0-size payload means FIN */ 257 return 0; 258 } 259 260 /* No payload or FIN */ 261 return -1; 262 } 263 264 static size_t hvs_channel_writable_bytes(struct vmbus_channel *chan) 265 { 266 u32 writeable = hv_get_bytes_to_write(&chan->outbound); 267 size_t ret; 268 269 /* The ringbuffer mustn't be 100% full, and we should reserve a 270 * zero-length-payload packet for the FIN: see hv_ringbuffer_write() 271 * and hvs_shutdown(). 272 */ 273 if (writeable <= HVS_PKT_LEN(1) + HVS_PKT_LEN(0)) 274 return 0; 275 276 ret = writeable - HVS_PKT_LEN(1) - HVS_PKT_LEN(0); 277 278 return round_down(ret, 8); 279 } 280 281 static int hvs_send_data(struct vmbus_channel *chan, 282 struct hvs_send_buf *send_buf, size_t to_write) 283 { 284 send_buf->hdr.pkt_type = 1; 285 send_buf->hdr.data_size = to_write; 286 return vmbus_sendpacket(chan, &send_buf->hdr, 287 sizeof(send_buf->hdr) + to_write, 288 0, VM_PKT_DATA_INBAND, 0); 289 } 290 291 static void hvs_channel_cb(void *ctx) 292 { 293 struct sock *sk = (struct sock *)ctx; 294 struct vsock_sock *vsk = vsock_sk(sk); 295 struct hvsock *hvs = vsk->trans; 296 struct vmbus_channel *chan = hvs->chan; 297 298 if (hvs_channel_readable(chan)) 299 sk->sk_data_ready(sk); 300 301 /* See hvs_stream_has_space(): when we reach here, the writable bytes 302 * may be already less than HVS_PKT_LEN(HVS_SEND_BUF_SIZE). 303 */ 304 if (hv_get_bytes_to_write(&chan->outbound) > 0) 305 sk->sk_write_space(sk); 306 } 307 308 static void hvs_close_connection(struct vmbus_channel *chan) 309 { 310 struct sock *sk = get_per_channel_state(chan); 311 struct vsock_sock *vsk = vsock_sk(sk); 312 313 lock_sock(sk); 314 315 sk->sk_state = SS_UNCONNECTED; 316 sock_set_flag(sk, SOCK_DONE); 317 vsk->peer_shutdown |= SEND_SHUTDOWN | RCV_SHUTDOWN; 318 319 sk->sk_state_change(sk); 320 321 release_sock(sk); 322 } 323 324 static void hvs_open_connection(struct vmbus_channel *chan) 325 { 326 uuid_le *if_instance, *if_type; 327 unsigned char conn_from_host; 328 329 struct sockaddr_vm addr; 330 struct sock *sk, *new = NULL; 331 struct vsock_sock *vnew; 332 struct hvsock *hvs, *hvs_new; 333 int ret; 334 335 if_type = &chan->offermsg.offer.if_type; 336 if_instance = &chan->offermsg.offer.if_instance; 337 conn_from_host = chan->offermsg.offer.u.pipe.user_def[0]; 338 339 /* The host or the VM should only listen on a port in 340 * [0, MAX_LISTEN_PORT] 341 */ 342 if (!is_valid_srv_id(if_type) || 343 get_port_by_srv_id(if_type) > MAX_LISTEN_PORT) 344 return; 345 346 hvs_addr_init(&addr, conn_from_host ? if_type : if_instance); 347 sk = vsock_find_bound_socket(&addr); 348 if (!sk) 349 return; 350 351 lock_sock(sk); 352 353 if ((conn_from_host && sk->sk_state != VSOCK_SS_LISTEN) || 354 (!conn_from_host && sk->sk_state != SS_CONNECTING)) 355 goto out; 356 357 if (conn_from_host) { 358 if (sk->sk_ack_backlog >= sk->sk_max_ack_backlog) 359 goto out; 360 361 new = __vsock_create(sock_net(sk), NULL, sk, GFP_KERNEL, 362 sk->sk_type, 0); 363 if (!new) 364 goto out; 365 366 new->sk_state = SS_CONNECTING; 367 vnew = vsock_sk(new); 368 hvs_new = vnew->trans; 369 hvs_new->chan = chan; 370 } else { 371 hvs = vsock_sk(sk)->trans; 372 hvs->chan = chan; 373 } 374 375 set_channel_read_mode(chan, HV_CALL_DIRECT); 376 ret = vmbus_open(chan, RINGBUFFER_HVS_SND_SIZE, 377 RINGBUFFER_HVS_RCV_SIZE, NULL, 0, 378 hvs_channel_cb, conn_from_host ? new : sk); 379 if (ret != 0) { 380 if (conn_from_host) { 381 hvs_new->chan = NULL; 382 sock_put(new); 383 } else { 384 hvs->chan = NULL; 385 } 386 goto out; 387 } 388 389 set_per_channel_state(chan, conn_from_host ? new : sk); 390 vmbus_set_chn_rescind_callback(chan, hvs_close_connection); 391 392 if (conn_from_host) { 393 new->sk_state = SS_CONNECTED; 394 sk->sk_ack_backlog++; 395 396 hvs_addr_init(&vnew->local_addr, if_type); 397 hvs_remote_addr_init(&vnew->remote_addr, &vnew->local_addr); 398 399 hvs_new->vm_srv_id = *if_type; 400 hvs_new->host_srv_id = *if_instance; 401 402 vsock_insert_connected(vnew); 403 404 vsock_enqueue_accept(sk, new); 405 } else { 406 sk->sk_state = SS_CONNECTED; 407 sk->sk_socket->state = SS_CONNECTED; 408 409 vsock_insert_connected(vsock_sk(sk)); 410 } 411 412 sk->sk_state_change(sk); 413 414 out: 415 /* Release refcnt obtained when we called vsock_find_bound_socket() */ 416 sock_put(sk); 417 418 release_sock(sk); 419 } 420 421 static u32 hvs_get_local_cid(void) 422 { 423 return VMADDR_CID_ANY; 424 } 425 426 static int hvs_sock_init(struct vsock_sock *vsk, struct vsock_sock *psk) 427 { 428 struct hvsock *hvs; 429 430 hvs = kzalloc(sizeof(*hvs), GFP_KERNEL); 431 if (!hvs) 432 return -ENOMEM; 433 434 vsk->trans = hvs; 435 hvs->vsk = vsk; 436 437 return 0; 438 } 439 440 static int hvs_connect(struct vsock_sock *vsk) 441 { 442 union hvs_service_id vm, host; 443 struct hvsock *h = vsk->trans; 444 445 vm.srv_id = srv_id_template; 446 vm.svm_port = vsk->local_addr.svm_port; 447 h->vm_srv_id = vm.srv_id; 448 449 host.srv_id = srv_id_template; 450 host.svm_port = vsk->remote_addr.svm_port; 451 h->host_srv_id = host.srv_id; 452 453 return vmbus_send_tl_connect_request(&h->vm_srv_id, &h->host_srv_id); 454 } 455 456 static int hvs_shutdown(struct vsock_sock *vsk, int mode) 457 { 458 struct sock *sk = sk_vsock(vsk); 459 struct vmpipe_proto_header hdr; 460 struct hvs_send_buf *send_buf; 461 struct hvsock *hvs; 462 463 if (!(mode & SEND_SHUTDOWN)) 464 return 0; 465 466 lock_sock(sk); 467 468 hvs = vsk->trans; 469 if (hvs->fin_sent) 470 goto out; 471 472 send_buf = (struct hvs_send_buf *)&hdr; 473 474 /* It can't fail: see hvs_channel_writable_bytes(). */ 475 (void)hvs_send_data(hvs->chan, send_buf, 0); 476 477 hvs->fin_sent = true; 478 out: 479 release_sock(sk); 480 return 0; 481 } 482 483 static void hvs_release(struct vsock_sock *vsk) 484 { 485 struct sock *sk = sk_vsock(vsk); 486 struct hvsock *hvs = vsk->trans; 487 struct vmbus_channel *chan; 488 489 lock_sock(sk); 490 491 sk->sk_state = SS_DISCONNECTING; 492 vsock_remove_sock(vsk); 493 494 release_sock(sk); 495 496 chan = hvs->chan; 497 if (chan) 498 hvs_shutdown(vsk, RCV_SHUTDOWN | SEND_SHUTDOWN); 499 500 } 501 502 static void hvs_destruct(struct vsock_sock *vsk) 503 { 504 struct hvsock *hvs = vsk->trans; 505 struct vmbus_channel *chan = hvs->chan; 506 507 if (chan) 508 vmbus_hvsock_device_unregister(chan); 509 510 kfree(hvs); 511 } 512 513 static int hvs_dgram_bind(struct vsock_sock *vsk, struct sockaddr_vm *addr) 514 { 515 return -EOPNOTSUPP; 516 } 517 518 static int hvs_dgram_dequeue(struct vsock_sock *vsk, struct msghdr *msg, 519 size_t len, int flags) 520 { 521 return -EOPNOTSUPP; 522 } 523 524 static int hvs_dgram_enqueue(struct vsock_sock *vsk, 525 struct sockaddr_vm *remote, struct msghdr *msg, 526 size_t dgram_len) 527 { 528 return -EOPNOTSUPP; 529 } 530 531 static bool hvs_dgram_allow(u32 cid, u32 port) 532 { 533 return false; 534 } 535 536 static int hvs_update_recv_data(struct hvsock *hvs) 537 { 538 struct hvs_recv_buf *recv_buf; 539 u32 payload_len; 540 541 recv_buf = (struct hvs_recv_buf *)(hvs->recv_desc + 1); 542 payload_len = recv_buf->hdr.data_size; 543 544 if (payload_len > HVS_MTU_SIZE) 545 return -EIO; 546 547 if (payload_len == 0) 548 hvs->vsk->peer_shutdown |= SEND_SHUTDOWN; 549 550 hvs->recv_data_len = payload_len; 551 hvs->recv_data_off = 0; 552 553 return 0; 554 } 555 556 static ssize_t hvs_stream_dequeue(struct vsock_sock *vsk, struct msghdr *msg, 557 size_t len, int flags) 558 { 559 struct hvsock *hvs = vsk->trans; 560 bool need_refill = !hvs->recv_desc; 561 struct hvs_recv_buf *recv_buf; 562 u32 to_read; 563 int ret; 564 565 if (flags & MSG_PEEK) 566 return -EOPNOTSUPP; 567 568 if (need_refill) { 569 hvs->recv_desc = hv_pkt_iter_first(hvs->chan); 570 ret = hvs_update_recv_data(hvs); 571 if (ret) 572 return ret; 573 } 574 575 recv_buf = (struct hvs_recv_buf *)(hvs->recv_desc + 1); 576 to_read = min_t(u32, len, hvs->recv_data_len); 577 ret = memcpy_to_msg(msg, recv_buf->data + hvs->recv_data_off, to_read); 578 if (ret != 0) 579 return ret; 580 581 hvs->recv_data_len -= to_read; 582 if (hvs->recv_data_len == 0) { 583 hvs->recv_desc = hv_pkt_iter_next(hvs->chan, hvs->recv_desc); 584 if (hvs->recv_desc) { 585 ret = hvs_update_recv_data(hvs); 586 if (ret) 587 return ret; 588 } 589 } else { 590 hvs->recv_data_off += to_read; 591 } 592 593 return to_read; 594 } 595 596 static ssize_t hvs_stream_enqueue(struct vsock_sock *vsk, struct msghdr *msg, 597 size_t len) 598 { 599 struct hvsock *hvs = vsk->trans; 600 struct vmbus_channel *chan = hvs->chan; 601 struct hvs_send_buf *send_buf; 602 ssize_t to_write, max_writable, ret; 603 604 BUILD_BUG_ON(sizeof(*send_buf) != PAGE_SIZE_4K); 605 606 send_buf = kmalloc(sizeof(*send_buf), GFP_KERNEL); 607 if (!send_buf) 608 return -ENOMEM; 609 610 max_writable = hvs_channel_writable_bytes(chan); 611 to_write = min_t(ssize_t, len, max_writable); 612 to_write = min_t(ssize_t, to_write, HVS_SEND_BUF_SIZE); 613 614 ret = memcpy_from_msg(send_buf->data, msg, to_write); 615 if (ret < 0) 616 goto out; 617 618 ret = hvs_send_data(hvs->chan, send_buf, to_write); 619 if (ret < 0) 620 goto out; 621 622 ret = to_write; 623 out: 624 kfree(send_buf); 625 return ret; 626 } 627 628 static s64 hvs_stream_has_data(struct vsock_sock *vsk) 629 { 630 struct hvsock *hvs = vsk->trans; 631 s64 ret; 632 633 if (hvs->recv_data_len > 0) 634 return 1; 635 636 switch (hvs_channel_readable_payload(hvs->chan)) { 637 case 1: 638 ret = 1; 639 break; 640 case 0: 641 vsk->peer_shutdown |= SEND_SHUTDOWN; 642 ret = 0; 643 break; 644 default: /* -1 */ 645 ret = 0; 646 break; 647 } 648 649 return ret; 650 } 651 652 static s64 hvs_stream_has_space(struct vsock_sock *vsk) 653 { 654 struct hvsock *hvs = vsk->trans; 655 struct vmbus_channel *chan = hvs->chan; 656 s64 ret; 657 658 ret = hvs_channel_writable_bytes(chan); 659 if (ret > 0) { 660 hvs_clear_channel_pending_send_size(chan); 661 } else { 662 /* See hvs_channel_cb() */ 663 hvs_set_channel_pending_send_size(chan); 664 665 /* Re-check the writable bytes to avoid race */ 666 ret = hvs_channel_writable_bytes(chan); 667 if (ret > 0) 668 hvs_clear_channel_pending_send_size(chan); 669 } 670 671 return ret; 672 } 673 674 static u64 hvs_stream_rcvhiwat(struct vsock_sock *vsk) 675 { 676 return HVS_MTU_SIZE + 1; 677 } 678 679 static bool hvs_stream_is_active(struct vsock_sock *vsk) 680 { 681 struct hvsock *hvs = vsk->trans; 682 683 return hvs->chan != NULL; 684 } 685 686 static bool hvs_stream_allow(u32 cid, u32 port) 687 { 688 /* The host's port range [MIN_HOST_EPHEMERAL_PORT, 0xFFFFFFFF) is 689 * reserved as ephemeral ports, which are used as the host's ports 690 * when the host initiates connections. 691 * 692 * Perform this check in the guest so an immediate error is produced 693 * instead of a timeout. 694 */ 695 if (port > MAX_HOST_LISTEN_PORT) 696 return false; 697 698 if (cid == VMADDR_CID_HOST) 699 return true; 700 701 return false; 702 } 703 704 static 705 int hvs_notify_poll_in(struct vsock_sock *vsk, size_t target, bool *readable) 706 { 707 struct hvsock *hvs = vsk->trans; 708 709 *readable = hvs_channel_readable(hvs->chan); 710 return 0; 711 } 712 713 static 714 int hvs_notify_poll_out(struct vsock_sock *vsk, size_t target, bool *writable) 715 { 716 *writable = hvs_stream_has_space(vsk) > 0; 717 718 return 0; 719 } 720 721 static 722 int hvs_notify_recv_init(struct vsock_sock *vsk, size_t target, 723 struct vsock_transport_recv_notify_data *d) 724 { 725 return 0; 726 } 727 728 static 729 int hvs_notify_recv_pre_block(struct vsock_sock *vsk, size_t target, 730 struct vsock_transport_recv_notify_data *d) 731 { 732 return 0; 733 } 734 735 static 736 int hvs_notify_recv_pre_dequeue(struct vsock_sock *vsk, size_t target, 737 struct vsock_transport_recv_notify_data *d) 738 { 739 return 0; 740 } 741 742 static 743 int hvs_notify_recv_post_dequeue(struct vsock_sock *vsk, size_t target, 744 ssize_t copied, bool data_read, 745 struct vsock_transport_recv_notify_data *d) 746 { 747 return 0; 748 } 749 750 static 751 int hvs_notify_send_init(struct vsock_sock *vsk, 752 struct vsock_transport_send_notify_data *d) 753 { 754 return 0; 755 } 756 757 static 758 int hvs_notify_send_pre_block(struct vsock_sock *vsk, 759 struct vsock_transport_send_notify_data *d) 760 { 761 return 0; 762 } 763 764 static 765 int hvs_notify_send_pre_enqueue(struct vsock_sock *vsk, 766 struct vsock_transport_send_notify_data *d) 767 { 768 return 0; 769 } 770 771 static 772 int hvs_notify_send_post_enqueue(struct vsock_sock *vsk, ssize_t written, 773 struct vsock_transport_send_notify_data *d) 774 { 775 return 0; 776 } 777 778 static void hvs_set_buffer_size(struct vsock_sock *vsk, u64 val) 779 { 780 /* Ignored. */ 781 } 782 783 static void hvs_set_min_buffer_size(struct vsock_sock *vsk, u64 val) 784 { 785 /* Ignored. */ 786 } 787 788 static void hvs_set_max_buffer_size(struct vsock_sock *vsk, u64 val) 789 { 790 /* Ignored. */ 791 } 792 793 static u64 hvs_get_buffer_size(struct vsock_sock *vsk) 794 { 795 return -ENOPROTOOPT; 796 } 797 798 static u64 hvs_get_min_buffer_size(struct vsock_sock *vsk) 799 { 800 return -ENOPROTOOPT; 801 } 802 803 static u64 hvs_get_max_buffer_size(struct vsock_sock *vsk) 804 { 805 return -ENOPROTOOPT; 806 } 807 808 static struct vsock_transport hvs_transport = { 809 .get_local_cid = hvs_get_local_cid, 810 811 .init = hvs_sock_init, 812 .destruct = hvs_destruct, 813 .release = hvs_release, 814 .connect = hvs_connect, 815 .shutdown = hvs_shutdown, 816 817 .dgram_bind = hvs_dgram_bind, 818 .dgram_dequeue = hvs_dgram_dequeue, 819 .dgram_enqueue = hvs_dgram_enqueue, 820 .dgram_allow = hvs_dgram_allow, 821 822 .stream_dequeue = hvs_stream_dequeue, 823 .stream_enqueue = hvs_stream_enqueue, 824 .stream_has_data = hvs_stream_has_data, 825 .stream_has_space = hvs_stream_has_space, 826 .stream_rcvhiwat = hvs_stream_rcvhiwat, 827 .stream_is_active = hvs_stream_is_active, 828 .stream_allow = hvs_stream_allow, 829 830 .notify_poll_in = hvs_notify_poll_in, 831 .notify_poll_out = hvs_notify_poll_out, 832 .notify_recv_init = hvs_notify_recv_init, 833 .notify_recv_pre_block = hvs_notify_recv_pre_block, 834 .notify_recv_pre_dequeue = hvs_notify_recv_pre_dequeue, 835 .notify_recv_post_dequeue = hvs_notify_recv_post_dequeue, 836 .notify_send_init = hvs_notify_send_init, 837 .notify_send_pre_block = hvs_notify_send_pre_block, 838 .notify_send_pre_enqueue = hvs_notify_send_pre_enqueue, 839 .notify_send_post_enqueue = hvs_notify_send_post_enqueue, 840 841 .set_buffer_size = hvs_set_buffer_size, 842 .set_min_buffer_size = hvs_set_min_buffer_size, 843 .set_max_buffer_size = hvs_set_max_buffer_size, 844 .get_buffer_size = hvs_get_buffer_size, 845 .get_min_buffer_size = hvs_get_min_buffer_size, 846 .get_max_buffer_size = hvs_get_max_buffer_size, 847 }; 848 849 static int hvs_probe(struct hv_device *hdev, 850 const struct hv_vmbus_device_id *dev_id) 851 { 852 struct vmbus_channel *chan = hdev->channel; 853 854 hvs_open_connection(chan); 855 856 /* Always return success to suppress the unnecessary error message 857 * in vmbus_probe(): on error the host will rescind the device in 858 * 30 seconds and we can do cleanup at that time in 859 * vmbus_onoffer_rescind(). 860 */ 861 return 0; 862 } 863 864 static int hvs_remove(struct hv_device *hdev) 865 { 866 struct vmbus_channel *chan = hdev->channel; 867 868 vmbus_close(chan); 869 870 return 0; 871 } 872 873 /* This isn't really used. See vmbus_match() and vmbus_probe() */ 874 static const struct hv_vmbus_device_id id_table[] = { 875 {}, 876 }; 877 878 static struct hv_driver hvs_drv = { 879 .name = "hv_sock", 880 .hvsock = true, 881 .id_table = id_table, 882 .probe = hvs_probe, 883 .remove = hvs_remove, 884 }; 885 886 static int __init hvs_init(void) 887 { 888 int ret; 889 890 if (vmbus_proto_version < VERSION_WIN10) 891 return -ENODEV; 892 893 ret = vmbus_driver_register(&hvs_drv); 894 if (ret != 0) 895 return ret; 896 897 ret = vsock_core_init(&hvs_transport); 898 if (ret) { 899 vmbus_driver_unregister(&hvs_drv); 900 return ret; 901 } 902 903 return 0; 904 } 905 906 static void __exit hvs_exit(void) 907 { 908 vsock_core_exit(); 909 vmbus_driver_unregister(&hvs_drv); 910 } 911 912 module_init(hvs_init); 913 module_exit(hvs_exit); 914 915 MODULE_DESCRIPTION("Hyper-V Sockets"); 916 MODULE_VERSION("1.0.0"); 917 MODULE_LICENSE("GPL"); 918 MODULE_ALIAS_NETPROTO(PF_VSOCK); 919