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 sk->sk_state = SS_UNCONNECTED; 314 sock_set_flag(sk, SOCK_DONE); 315 vsk->peer_shutdown |= SEND_SHUTDOWN | RCV_SHUTDOWN; 316 317 sk->sk_state_change(sk); 318 } 319 320 static void hvs_open_connection(struct vmbus_channel *chan) 321 { 322 uuid_le *if_instance, *if_type; 323 unsigned char conn_from_host; 324 325 struct sockaddr_vm addr; 326 struct sock *sk, *new = NULL; 327 struct vsock_sock *vnew; 328 struct hvsock *hvs, *hvs_new; 329 int ret; 330 331 if_type = &chan->offermsg.offer.if_type; 332 if_instance = &chan->offermsg.offer.if_instance; 333 conn_from_host = chan->offermsg.offer.u.pipe.user_def[0]; 334 335 /* The host or the VM should only listen on a port in 336 * [0, MAX_LISTEN_PORT] 337 */ 338 if (!is_valid_srv_id(if_type) || 339 get_port_by_srv_id(if_type) > MAX_LISTEN_PORT) 340 return; 341 342 hvs_addr_init(&addr, conn_from_host ? if_type : if_instance); 343 sk = vsock_find_bound_socket(&addr); 344 if (!sk) 345 return; 346 347 if ((conn_from_host && sk->sk_state != VSOCK_SS_LISTEN) || 348 (!conn_from_host && sk->sk_state != SS_CONNECTING)) 349 goto out; 350 351 if (conn_from_host) { 352 if (sk->sk_ack_backlog >= sk->sk_max_ack_backlog) 353 goto out; 354 355 new = __vsock_create(sock_net(sk), NULL, sk, GFP_KERNEL, 356 sk->sk_type, 0); 357 if (!new) 358 goto out; 359 360 new->sk_state = SS_CONNECTING; 361 vnew = vsock_sk(new); 362 hvs_new = vnew->trans; 363 hvs_new->chan = chan; 364 } else { 365 hvs = vsock_sk(sk)->trans; 366 hvs->chan = chan; 367 } 368 369 set_channel_read_mode(chan, HV_CALL_DIRECT); 370 ret = vmbus_open(chan, RINGBUFFER_HVS_SND_SIZE, 371 RINGBUFFER_HVS_RCV_SIZE, NULL, 0, 372 hvs_channel_cb, conn_from_host ? new : sk); 373 if (ret != 0) { 374 if (conn_from_host) { 375 hvs_new->chan = NULL; 376 sock_put(new); 377 } else { 378 hvs->chan = NULL; 379 } 380 goto out; 381 } 382 383 set_per_channel_state(chan, conn_from_host ? new : sk); 384 vmbus_set_chn_rescind_callback(chan, hvs_close_connection); 385 386 if (conn_from_host) { 387 new->sk_state = SS_CONNECTED; 388 sk->sk_ack_backlog++; 389 390 hvs_addr_init(&vnew->local_addr, if_type); 391 hvs_remote_addr_init(&vnew->remote_addr, &vnew->local_addr); 392 393 hvs_new->vm_srv_id = *if_type; 394 hvs_new->host_srv_id = *if_instance; 395 396 vsock_insert_connected(vnew); 397 398 lock_sock(sk); 399 vsock_enqueue_accept(sk, new); 400 release_sock(sk); 401 } else { 402 sk->sk_state = SS_CONNECTED; 403 sk->sk_socket->state = SS_CONNECTED; 404 405 vsock_insert_connected(vsock_sk(sk)); 406 } 407 408 sk->sk_state_change(sk); 409 410 out: 411 /* Release refcnt obtained when we called vsock_find_bound_socket() */ 412 sock_put(sk); 413 } 414 415 static u32 hvs_get_local_cid(void) 416 { 417 return VMADDR_CID_ANY; 418 } 419 420 static int hvs_sock_init(struct vsock_sock *vsk, struct vsock_sock *psk) 421 { 422 struct hvsock *hvs; 423 424 hvs = kzalloc(sizeof(*hvs), GFP_KERNEL); 425 if (!hvs) 426 return -ENOMEM; 427 428 vsk->trans = hvs; 429 hvs->vsk = vsk; 430 431 return 0; 432 } 433 434 static int hvs_connect(struct vsock_sock *vsk) 435 { 436 union hvs_service_id vm, host; 437 struct hvsock *h = vsk->trans; 438 439 vm.srv_id = srv_id_template; 440 vm.svm_port = vsk->local_addr.svm_port; 441 h->vm_srv_id = vm.srv_id; 442 443 host.srv_id = srv_id_template; 444 host.svm_port = vsk->remote_addr.svm_port; 445 h->host_srv_id = host.srv_id; 446 447 return vmbus_send_tl_connect_request(&h->vm_srv_id, &h->host_srv_id); 448 } 449 450 static int hvs_shutdown(struct vsock_sock *vsk, int mode) 451 { 452 struct sock *sk = sk_vsock(vsk); 453 struct vmpipe_proto_header hdr; 454 struct hvs_send_buf *send_buf; 455 struct hvsock *hvs; 456 457 if (!(mode & SEND_SHUTDOWN)) 458 return 0; 459 460 lock_sock(sk); 461 462 hvs = vsk->trans; 463 if (hvs->fin_sent) 464 goto out; 465 466 send_buf = (struct hvs_send_buf *)&hdr; 467 468 /* It can't fail: see hvs_channel_writable_bytes(). */ 469 (void)hvs_send_data(hvs->chan, send_buf, 0); 470 471 hvs->fin_sent = true; 472 out: 473 release_sock(sk); 474 return 0; 475 } 476 477 static void hvs_release(struct vsock_sock *vsk) 478 { 479 struct hvsock *hvs = vsk->trans; 480 struct vmbus_channel *chan = hvs->chan; 481 482 if (chan) 483 hvs_shutdown(vsk, RCV_SHUTDOWN | SEND_SHUTDOWN); 484 485 vsock_remove_sock(vsk); 486 } 487 488 static void hvs_destruct(struct vsock_sock *vsk) 489 { 490 struct hvsock *hvs = vsk->trans; 491 struct vmbus_channel *chan = hvs->chan; 492 493 if (chan) 494 vmbus_hvsock_device_unregister(chan); 495 496 kfree(hvs); 497 } 498 499 static int hvs_dgram_bind(struct vsock_sock *vsk, struct sockaddr_vm *addr) 500 { 501 return -EOPNOTSUPP; 502 } 503 504 static int hvs_dgram_dequeue(struct vsock_sock *vsk, struct msghdr *msg, 505 size_t len, int flags) 506 { 507 return -EOPNOTSUPP; 508 } 509 510 static int hvs_dgram_enqueue(struct vsock_sock *vsk, 511 struct sockaddr_vm *remote, struct msghdr *msg, 512 size_t dgram_len) 513 { 514 return -EOPNOTSUPP; 515 } 516 517 static bool hvs_dgram_allow(u32 cid, u32 port) 518 { 519 return false; 520 } 521 522 static int hvs_update_recv_data(struct hvsock *hvs) 523 { 524 struct hvs_recv_buf *recv_buf; 525 u32 payload_len; 526 527 recv_buf = (struct hvs_recv_buf *)(hvs->recv_desc + 1); 528 payload_len = recv_buf->hdr.data_size; 529 530 if (payload_len > HVS_MTU_SIZE) 531 return -EIO; 532 533 if (payload_len == 0) 534 hvs->vsk->peer_shutdown |= SEND_SHUTDOWN; 535 536 hvs->recv_data_len = payload_len; 537 hvs->recv_data_off = 0; 538 539 return 0; 540 } 541 542 static ssize_t hvs_stream_dequeue(struct vsock_sock *vsk, struct msghdr *msg, 543 size_t len, int flags) 544 { 545 struct hvsock *hvs = vsk->trans; 546 bool need_refill = !hvs->recv_desc; 547 struct hvs_recv_buf *recv_buf; 548 u32 to_read; 549 int ret; 550 551 if (flags & MSG_PEEK) 552 return -EOPNOTSUPP; 553 554 if (need_refill) { 555 hvs->recv_desc = hv_pkt_iter_first(hvs->chan); 556 ret = hvs_update_recv_data(hvs); 557 if (ret) 558 return ret; 559 } 560 561 recv_buf = (struct hvs_recv_buf *)(hvs->recv_desc + 1); 562 to_read = min_t(u32, len, hvs->recv_data_len); 563 ret = memcpy_to_msg(msg, recv_buf->data + hvs->recv_data_off, to_read); 564 if (ret != 0) 565 return ret; 566 567 hvs->recv_data_len -= to_read; 568 if (hvs->recv_data_len == 0) { 569 hvs->recv_desc = hv_pkt_iter_next(hvs->chan, hvs->recv_desc); 570 if (hvs->recv_desc) { 571 ret = hvs_update_recv_data(hvs); 572 if (ret) 573 return ret; 574 } 575 } else { 576 hvs->recv_data_off += to_read; 577 } 578 579 return to_read; 580 } 581 582 static ssize_t hvs_stream_enqueue(struct vsock_sock *vsk, struct msghdr *msg, 583 size_t len) 584 { 585 struct hvsock *hvs = vsk->trans; 586 struct vmbus_channel *chan = hvs->chan; 587 struct hvs_send_buf *send_buf; 588 ssize_t to_write, max_writable, ret; 589 590 BUILD_BUG_ON(sizeof(*send_buf) != PAGE_SIZE_4K); 591 592 send_buf = kmalloc(sizeof(*send_buf), GFP_KERNEL); 593 if (!send_buf) 594 return -ENOMEM; 595 596 max_writable = hvs_channel_writable_bytes(chan); 597 to_write = min_t(ssize_t, len, max_writable); 598 to_write = min_t(ssize_t, to_write, HVS_SEND_BUF_SIZE); 599 600 ret = memcpy_from_msg(send_buf->data, msg, to_write); 601 if (ret < 0) 602 goto out; 603 604 ret = hvs_send_data(hvs->chan, send_buf, to_write); 605 if (ret < 0) 606 goto out; 607 608 ret = to_write; 609 out: 610 kfree(send_buf); 611 return ret; 612 } 613 614 static s64 hvs_stream_has_data(struct vsock_sock *vsk) 615 { 616 struct hvsock *hvs = vsk->trans; 617 s64 ret; 618 619 if (hvs->recv_data_len > 0) 620 return 1; 621 622 switch (hvs_channel_readable_payload(hvs->chan)) { 623 case 1: 624 ret = 1; 625 break; 626 case 0: 627 vsk->peer_shutdown |= SEND_SHUTDOWN; 628 ret = 0; 629 break; 630 default: /* -1 */ 631 ret = 0; 632 break; 633 } 634 635 return ret; 636 } 637 638 static s64 hvs_stream_has_space(struct vsock_sock *vsk) 639 { 640 struct hvsock *hvs = vsk->trans; 641 struct vmbus_channel *chan = hvs->chan; 642 s64 ret; 643 644 ret = hvs_channel_writable_bytes(chan); 645 if (ret > 0) { 646 hvs_clear_channel_pending_send_size(chan); 647 } else { 648 /* See hvs_channel_cb() */ 649 hvs_set_channel_pending_send_size(chan); 650 651 /* Re-check the writable bytes to avoid race */ 652 ret = hvs_channel_writable_bytes(chan); 653 if (ret > 0) 654 hvs_clear_channel_pending_send_size(chan); 655 } 656 657 return ret; 658 } 659 660 static u64 hvs_stream_rcvhiwat(struct vsock_sock *vsk) 661 { 662 return HVS_MTU_SIZE + 1; 663 } 664 665 static bool hvs_stream_is_active(struct vsock_sock *vsk) 666 { 667 struct hvsock *hvs = vsk->trans; 668 669 return hvs->chan != NULL; 670 } 671 672 static bool hvs_stream_allow(u32 cid, u32 port) 673 { 674 /* The host's port range [MIN_HOST_EPHEMERAL_PORT, 0xFFFFFFFF) is 675 * reserved as ephemeral ports, which are used as the host's ports 676 * when the host initiates connections. 677 * 678 * Perform this check in the guest so an immediate error is produced 679 * instead of a timeout. 680 */ 681 if (port > MAX_HOST_LISTEN_PORT) 682 return false; 683 684 if (cid == VMADDR_CID_HOST) 685 return true; 686 687 return false; 688 } 689 690 static 691 int hvs_notify_poll_in(struct vsock_sock *vsk, size_t target, bool *readable) 692 { 693 struct hvsock *hvs = vsk->trans; 694 695 *readable = hvs_channel_readable(hvs->chan); 696 return 0; 697 } 698 699 static 700 int hvs_notify_poll_out(struct vsock_sock *vsk, size_t target, bool *writable) 701 { 702 *writable = hvs_stream_has_space(vsk) > 0; 703 704 return 0; 705 } 706 707 static 708 int hvs_notify_recv_init(struct vsock_sock *vsk, size_t target, 709 struct vsock_transport_recv_notify_data *d) 710 { 711 return 0; 712 } 713 714 static 715 int hvs_notify_recv_pre_block(struct vsock_sock *vsk, size_t target, 716 struct vsock_transport_recv_notify_data *d) 717 { 718 return 0; 719 } 720 721 static 722 int hvs_notify_recv_pre_dequeue(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_post_dequeue(struct vsock_sock *vsk, size_t target, 730 ssize_t copied, bool data_read, 731 struct vsock_transport_recv_notify_data *d) 732 { 733 return 0; 734 } 735 736 static 737 int hvs_notify_send_init(struct vsock_sock *vsk, 738 struct vsock_transport_send_notify_data *d) 739 { 740 return 0; 741 } 742 743 static 744 int hvs_notify_send_pre_block(struct vsock_sock *vsk, 745 struct vsock_transport_send_notify_data *d) 746 { 747 return 0; 748 } 749 750 static 751 int hvs_notify_send_pre_enqueue(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_post_enqueue(struct vsock_sock *vsk, ssize_t written, 759 struct vsock_transport_send_notify_data *d) 760 { 761 return 0; 762 } 763 764 static void hvs_set_buffer_size(struct vsock_sock *vsk, u64 val) 765 { 766 /* Ignored. */ 767 } 768 769 static void hvs_set_min_buffer_size(struct vsock_sock *vsk, u64 val) 770 { 771 /* Ignored. */ 772 } 773 774 static void hvs_set_max_buffer_size(struct vsock_sock *vsk, u64 val) 775 { 776 /* Ignored. */ 777 } 778 779 static u64 hvs_get_buffer_size(struct vsock_sock *vsk) 780 { 781 return -ENOPROTOOPT; 782 } 783 784 static u64 hvs_get_min_buffer_size(struct vsock_sock *vsk) 785 { 786 return -ENOPROTOOPT; 787 } 788 789 static u64 hvs_get_max_buffer_size(struct vsock_sock *vsk) 790 { 791 return -ENOPROTOOPT; 792 } 793 794 static struct vsock_transport hvs_transport = { 795 .get_local_cid = hvs_get_local_cid, 796 797 .init = hvs_sock_init, 798 .destruct = hvs_destruct, 799 .release = hvs_release, 800 .connect = hvs_connect, 801 .shutdown = hvs_shutdown, 802 803 .dgram_bind = hvs_dgram_bind, 804 .dgram_dequeue = hvs_dgram_dequeue, 805 .dgram_enqueue = hvs_dgram_enqueue, 806 .dgram_allow = hvs_dgram_allow, 807 808 .stream_dequeue = hvs_stream_dequeue, 809 .stream_enqueue = hvs_stream_enqueue, 810 .stream_has_data = hvs_stream_has_data, 811 .stream_has_space = hvs_stream_has_space, 812 .stream_rcvhiwat = hvs_stream_rcvhiwat, 813 .stream_is_active = hvs_stream_is_active, 814 .stream_allow = hvs_stream_allow, 815 816 .notify_poll_in = hvs_notify_poll_in, 817 .notify_poll_out = hvs_notify_poll_out, 818 .notify_recv_init = hvs_notify_recv_init, 819 .notify_recv_pre_block = hvs_notify_recv_pre_block, 820 .notify_recv_pre_dequeue = hvs_notify_recv_pre_dequeue, 821 .notify_recv_post_dequeue = hvs_notify_recv_post_dequeue, 822 .notify_send_init = hvs_notify_send_init, 823 .notify_send_pre_block = hvs_notify_send_pre_block, 824 .notify_send_pre_enqueue = hvs_notify_send_pre_enqueue, 825 .notify_send_post_enqueue = hvs_notify_send_post_enqueue, 826 827 .set_buffer_size = hvs_set_buffer_size, 828 .set_min_buffer_size = hvs_set_min_buffer_size, 829 .set_max_buffer_size = hvs_set_max_buffer_size, 830 .get_buffer_size = hvs_get_buffer_size, 831 .get_min_buffer_size = hvs_get_min_buffer_size, 832 .get_max_buffer_size = hvs_get_max_buffer_size, 833 }; 834 835 static int hvs_probe(struct hv_device *hdev, 836 const struct hv_vmbus_device_id *dev_id) 837 { 838 struct vmbus_channel *chan = hdev->channel; 839 840 hvs_open_connection(chan); 841 842 /* Always return success to suppress the unnecessary error message 843 * in vmbus_probe(): on error the host will rescind the device in 844 * 30 seconds and we can do cleanup at that time in 845 * vmbus_onoffer_rescind(). 846 */ 847 return 0; 848 } 849 850 static int hvs_remove(struct hv_device *hdev) 851 { 852 struct vmbus_channel *chan = hdev->channel; 853 854 vmbus_close(chan); 855 856 return 0; 857 } 858 859 /* This isn't really used. See vmbus_match() and vmbus_probe() */ 860 static const struct hv_vmbus_device_id id_table[] = { 861 {}, 862 }; 863 864 static struct hv_driver hvs_drv = { 865 .name = "hv_sock", 866 .hvsock = true, 867 .id_table = id_table, 868 .probe = hvs_probe, 869 .remove = hvs_remove, 870 }; 871 872 static int __init hvs_init(void) 873 { 874 int ret; 875 876 if (vmbus_proto_version < VERSION_WIN10) 877 return -ENODEV; 878 879 ret = vmbus_driver_register(&hvs_drv); 880 if (ret != 0) 881 return ret; 882 883 ret = vsock_core_init(&hvs_transport); 884 if (ret) { 885 vmbus_driver_unregister(&hvs_drv); 886 return ret; 887 } 888 889 return 0; 890 } 891 892 static void __exit hvs_exit(void) 893 { 894 vsock_core_exit(); 895 vmbus_driver_unregister(&hvs_drv); 896 } 897 898 module_init(hvs_init); 899 module_exit(hvs_exit); 900 901 MODULE_DESCRIPTION("Hyper-V Sockets"); 902 MODULE_VERSION("1.0.0"); 903 MODULE_LICENSE("GPL"); 904 MODULE_ALIAS_NETPROTO(PF_VSOCK); 905