1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2009, Citrix Systems, Inc. 4 * Copyright (c) 2010, Microsoft Corporation. 5 * Copyright (c) 2011, Novell Inc. 6 */ 7 #include <linux/init.h> 8 #include <linux/module.h> 9 #include <linux/device.h> 10 #include <linux/completion.h> 11 #include <linux/input.h> 12 #include <linux/hid.h> 13 #include <linux/hiddev.h> 14 #include <linux/hyperv.h> 15 16 17 struct hv_input_dev_info { 18 unsigned int size; 19 unsigned short vendor; 20 unsigned short product; 21 unsigned short version; 22 unsigned short reserved[11]; 23 }; 24 25 /* The maximum size of a synthetic input message. */ 26 #define SYNTHHID_MAX_INPUT_REPORT_SIZE 16 27 28 /* 29 * Current version 30 * 31 * History: 32 * Beta, RC < 2008/1/22 1,0 33 * RC > 2008/1/22 2,0 34 */ 35 #define SYNTHHID_INPUT_VERSION_MAJOR 2 36 #define SYNTHHID_INPUT_VERSION_MINOR 0 37 #define SYNTHHID_INPUT_VERSION (SYNTHHID_INPUT_VERSION_MINOR | \ 38 (SYNTHHID_INPUT_VERSION_MAJOR << 16)) 39 40 41 #pragma pack(push, 1) 42 /* 43 * Message types in the synthetic input protocol 44 */ 45 enum synthhid_msg_type { 46 SYNTH_HID_PROTOCOL_REQUEST, 47 SYNTH_HID_PROTOCOL_RESPONSE, 48 SYNTH_HID_INITIAL_DEVICE_INFO, 49 SYNTH_HID_INITIAL_DEVICE_INFO_ACK, 50 SYNTH_HID_INPUT_REPORT, 51 SYNTH_HID_MAX 52 }; 53 54 /* 55 * Basic message structures. 56 */ 57 struct synthhid_msg_hdr { 58 enum synthhid_msg_type type; 59 u32 size; 60 }; 61 62 struct synthhid_msg { 63 struct synthhid_msg_hdr header; 64 char data[1]; /* Enclosed message */ 65 }; 66 67 union synthhid_version { 68 struct { 69 u16 minor_version; 70 u16 major_version; 71 }; 72 u32 version; 73 }; 74 75 /* 76 * Protocol messages 77 */ 78 struct synthhid_protocol_request { 79 struct synthhid_msg_hdr header; 80 union synthhid_version version_requested; 81 }; 82 83 struct synthhid_protocol_response { 84 struct synthhid_msg_hdr header; 85 union synthhid_version version_requested; 86 unsigned char approved; 87 }; 88 89 struct synthhid_device_info { 90 struct synthhid_msg_hdr header; 91 struct hv_input_dev_info hid_dev_info; 92 struct hid_descriptor hid_descriptor; 93 }; 94 95 struct synthhid_device_info_ack { 96 struct synthhid_msg_hdr header; 97 unsigned char reserved; 98 }; 99 100 struct synthhid_input_report { 101 struct synthhid_msg_hdr header; 102 char buffer[1]; 103 }; 104 105 #pragma pack(pop) 106 107 #define INPUTVSC_SEND_RING_BUFFER_SIZE (10*PAGE_SIZE) 108 #define INPUTVSC_RECV_RING_BUFFER_SIZE (10*PAGE_SIZE) 109 110 111 enum pipe_prot_msg_type { 112 PIPE_MESSAGE_INVALID, 113 PIPE_MESSAGE_DATA, 114 PIPE_MESSAGE_MAXIMUM 115 }; 116 117 118 struct pipe_prt_msg { 119 enum pipe_prot_msg_type type; 120 u32 size; 121 char data[1]; 122 }; 123 124 struct mousevsc_prt_msg { 125 enum pipe_prot_msg_type type; 126 u32 size; 127 union { 128 struct synthhid_protocol_request request; 129 struct synthhid_protocol_response response; 130 struct synthhid_device_info_ack ack; 131 }; 132 }; 133 134 /* 135 * Represents an mousevsc device 136 */ 137 struct mousevsc_dev { 138 struct hv_device *device; 139 bool init_complete; 140 bool connected; 141 struct mousevsc_prt_msg protocol_req; 142 struct mousevsc_prt_msg protocol_resp; 143 /* Synchronize the request/response if needed */ 144 struct completion wait_event; 145 int dev_info_status; 146 147 struct hid_descriptor *hid_desc; 148 unsigned char *report_desc; 149 u32 report_desc_size; 150 struct hv_input_dev_info hid_dev_info; 151 struct hid_device *hid_device; 152 u8 input_buf[HID_MAX_BUFFER_SIZE]; 153 }; 154 155 156 static struct mousevsc_dev *mousevsc_alloc_device(struct hv_device *device) 157 { 158 struct mousevsc_dev *input_dev; 159 160 input_dev = kzalloc(sizeof(struct mousevsc_dev), GFP_KERNEL); 161 162 if (!input_dev) 163 return NULL; 164 165 input_dev->device = device; 166 hv_set_drvdata(device, input_dev); 167 init_completion(&input_dev->wait_event); 168 input_dev->init_complete = false; 169 170 return input_dev; 171 } 172 173 static void mousevsc_free_device(struct mousevsc_dev *device) 174 { 175 kfree(device->hid_desc); 176 kfree(device->report_desc); 177 hv_set_drvdata(device->device, NULL); 178 kfree(device); 179 } 180 181 static void mousevsc_on_receive_device_info(struct mousevsc_dev *input_device, 182 struct synthhid_device_info *device_info) 183 { 184 int ret = 0; 185 struct hid_descriptor *desc; 186 struct mousevsc_prt_msg ack; 187 188 input_device->dev_info_status = -ENOMEM; 189 190 input_device->hid_dev_info = device_info->hid_dev_info; 191 desc = &device_info->hid_descriptor; 192 if (desc->bLength == 0) 193 goto cleanup; 194 195 input_device->hid_desc = kmemdup(desc, desc->bLength, GFP_ATOMIC); 196 197 if (!input_device->hid_desc) 198 goto cleanup; 199 200 input_device->report_desc_size = desc->desc[0].wDescriptorLength; 201 if (input_device->report_desc_size == 0) { 202 input_device->dev_info_status = -EINVAL; 203 goto cleanup; 204 } 205 206 input_device->report_desc = kzalloc(input_device->report_desc_size, 207 GFP_ATOMIC); 208 209 if (!input_device->report_desc) { 210 input_device->dev_info_status = -ENOMEM; 211 goto cleanup; 212 } 213 214 memcpy(input_device->report_desc, 215 ((unsigned char *)desc) + desc->bLength, 216 desc->desc[0].wDescriptorLength); 217 218 /* Send the ack */ 219 memset(&ack, 0, sizeof(struct mousevsc_prt_msg)); 220 221 ack.type = PIPE_MESSAGE_DATA; 222 ack.size = sizeof(struct synthhid_device_info_ack); 223 224 ack.ack.header.type = SYNTH_HID_INITIAL_DEVICE_INFO_ACK; 225 ack.ack.header.size = 1; 226 ack.ack.reserved = 0; 227 228 ret = vmbus_sendpacket(input_device->device->channel, 229 &ack, 230 sizeof(struct pipe_prt_msg) - sizeof(unsigned char) + 231 sizeof(struct synthhid_device_info_ack), 232 (unsigned long)&ack, 233 VM_PKT_DATA_INBAND, 234 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); 235 236 if (!ret) 237 input_device->dev_info_status = 0; 238 239 cleanup: 240 complete(&input_device->wait_event); 241 242 return; 243 } 244 245 static void mousevsc_on_receive(struct hv_device *device, 246 struct vmpacket_descriptor *packet) 247 { 248 struct pipe_prt_msg *pipe_msg; 249 struct synthhid_msg *hid_msg; 250 struct mousevsc_dev *input_dev = hv_get_drvdata(device); 251 struct synthhid_input_report *input_report; 252 size_t len; 253 254 pipe_msg = (struct pipe_prt_msg *)((unsigned long)packet + 255 (packet->offset8 << 3)); 256 257 if (pipe_msg->type != PIPE_MESSAGE_DATA) 258 return; 259 260 hid_msg = (struct synthhid_msg *)pipe_msg->data; 261 262 switch (hid_msg->header.type) { 263 case SYNTH_HID_PROTOCOL_RESPONSE: 264 /* 265 * While it will be impossible for us to protect against 266 * malicious/buggy hypervisor/host, add a check here to 267 * ensure we don't corrupt memory. 268 */ 269 if ((pipe_msg->size + sizeof(struct pipe_prt_msg) 270 - sizeof(unsigned char)) 271 > sizeof(struct mousevsc_prt_msg)) { 272 WARN_ON(1); 273 break; 274 } 275 276 memcpy(&input_dev->protocol_resp, pipe_msg, 277 pipe_msg->size + sizeof(struct pipe_prt_msg) - 278 sizeof(unsigned char)); 279 complete(&input_dev->wait_event); 280 break; 281 282 case SYNTH_HID_INITIAL_DEVICE_INFO: 283 WARN_ON(pipe_msg->size < sizeof(struct hv_input_dev_info)); 284 285 /* 286 * Parse out the device info into device attr, 287 * hid desc and report desc 288 */ 289 mousevsc_on_receive_device_info(input_dev, 290 (struct synthhid_device_info *)pipe_msg->data); 291 break; 292 case SYNTH_HID_INPUT_REPORT: 293 input_report = 294 (struct synthhid_input_report *)pipe_msg->data; 295 if (!input_dev->init_complete) 296 break; 297 298 len = min(input_report->header.size, 299 (u32)sizeof(input_dev->input_buf)); 300 memcpy(input_dev->input_buf, input_report->buffer, len); 301 hid_input_report(input_dev->hid_device, HID_INPUT_REPORT, 302 input_dev->input_buf, len, 1); 303 304 pm_wakeup_hard_event(&input_dev->device->device); 305 306 break; 307 default: 308 pr_err("unsupported hid msg type - type %d len %d\n", 309 hid_msg->header.type, hid_msg->header.size); 310 break; 311 } 312 313 } 314 315 static void mousevsc_on_channel_callback(void *context) 316 { 317 const int packet_size = 0x100; 318 int ret; 319 struct hv_device *device = context; 320 u32 bytes_recvd; 321 u64 req_id; 322 struct vmpacket_descriptor *desc; 323 unsigned char *buffer; 324 int bufferlen = packet_size; 325 326 buffer = kmalloc(bufferlen, GFP_ATOMIC); 327 if (!buffer) 328 return; 329 330 do { 331 ret = vmbus_recvpacket_raw(device->channel, buffer, 332 bufferlen, &bytes_recvd, &req_id); 333 334 switch (ret) { 335 case 0: 336 if (bytes_recvd <= 0) { 337 kfree(buffer); 338 return; 339 } 340 desc = (struct vmpacket_descriptor *)buffer; 341 342 switch (desc->type) { 343 case VM_PKT_COMP: 344 break; 345 346 case VM_PKT_DATA_INBAND: 347 mousevsc_on_receive(device, desc); 348 break; 349 350 default: 351 pr_err("unhandled packet type %d, tid %llx len %d\n", 352 desc->type, req_id, bytes_recvd); 353 break; 354 } 355 356 break; 357 358 case -ENOBUFS: 359 kfree(buffer); 360 /* Handle large packet */ 361 bufferlen = bytes_recvd; 362 buffer = kmalloc(bytes_recvd, GFP_ATOMIC); 363 364 if (!buffer) 365 return; 366 367 break; 368 } 369 } while (1); 370 371 } 372 373 static int mousevsc_connect_to_vsp(struct hv_device *device) 374 { 375 int ret = 0; 376 unsigned long t; 377 struct mousevsc_dev *input_dev = hv_get_drvdata(device); 378 struct mousevsc_prt_msg *request; 379 struct mousevsc_prt_msg *response; 380 381 request = &input_dev->protocol_req; 382 memset(request, 0, sizeof(struct mousevsc_prt_msg)); 383 384 request->type = PIPE_MESSAGE_DATA; 385 request->size = sizeof(struct synthhid_protocol_request); 386 request->request.header.type = SYNTH_HID_PROTOCOL_REQUEST; 387 request->request.header.size = sizeof(unsigned int); 388 request->request.version_requested.version = SYNTHHID_INPUT_VERSION; 389 390 ret = vmbus_sendpacket(device->channel, request, 391 sizeof(struct pipe_prt_msg) - 392 sizeof(unsigned char) + 393 sizeof(struct synthhid_protocol_request), 394 (unsigned long)request, 395 VM_PKT_DATA_INBAND, 396 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); 397 if (ret) 398 goto cleanup; 399 400 t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ); 401 if (!t) { 402 ret = -ETIMEDOUT; 403 goto cleanup; 404 } 405 406 response = &input_dev->protocol_resp; 407 408 if (!response->response.approved) { 409 pr_err("synthhid protocol request failed (version %d)\n", 410 SYNTHHID_INPUT_VERSION); 411 ret = -ENODEV; 412 goto cleanup; 413 } 414 415 t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ); 416 if (!t) { 417 ret = -ETIMEDOUT; 418 goto cleanup; 419 } 420 421 /* 422 * We should have gotten the device attr, hid desc and report 423 * desc at this point 424 */ 425 ret = input_dev->dev_info_status; 426 427 cleanup: 428 return ret; 429 } 430 431 static int mousevsc_hid_parse(struct hid_device *hid) 432 { 433 struct hv_device *dev = hid_get_drvdata(hid); 434 struct mousevsc_dev *input_dev = hv_get_drvdata(dev); 435 436 return hid_parse_report(hid, input_dev->report_desc, 437 input_dev->report_desc_size); 438 } 439 440 static int mousevsc_hid_open(struct hid_device *hid) 441 { 442 return 0; 443 } 444 445 static int mousevsc_hid_start(struct hid_device *hid) 446 { 447 return 0; 448 } 449 450 static void mousevsc_hid_close(struct hid_device *hid) 451 { 452 } 453 454 static void mousevsc_hid_stop(struct hid_device *hid) 455 { 456 } 457 458 static int mousevsc_hid_raw_request(struct hid_device *hid, 459 unsigned char report_num, 460 __u8 *buf, size_t len, 461 unsigned char rtype, 462 int reqtype) 463 { 464 return 0; 465 } 466 467 static struct hid_ll_driver mousevsc_ll_driver = { 468 .parse = mousevsc_hid_parse, 469 .open = mousevsc_hid_open, 470 .close = mousevsc_hid_close, 471 .start = mousevsc_hid_start, 472 .stop = mousevsc_hid_stop, 473 .raw_request = mousevsc_hid_raw_request, 474 }; 475 476 static struct hid_driver mousevsc_hid_driver; 477 478 static int mousevsc_probe(struct hv_device *device, 479 const struct hv_vmbus_device_id *dev_id) 480 { 481 int ret; 482 struct mousevsc_dev *input_dev; 483 struct hid_device *hid_dev; 484 485 input_dev = mousevsc_alloc_device(device); 486 487 if (!input_dev) 488 return -ENOMEM; 489 490 ret = vmbus_open(device->channel, 491 INPUTVSC_SEND_RING_BUFFER_SIZE, 492 INPUTVSC_RECV_RING_BUFFER_SIZE, 493 NULL, 494 0, 495 mousevsc_on_channel_callback, 496 device 497 ); 498 499 if (ret) 500 goto probe_err0; 501 502 ret = mousevsc_connect_to_vsp(device); 503 504 if (ret) 505 goto probe_err1; 506 507 /* workaround SA-167 */ 508 if (input_dev->report_desc[14] == 0x25) 509 input_dev->report_desc[14] = 0x29; 510 511 hid_dev = hid_allocate_device(); 512 if (IS_ERR(hid_dev)) { 513 ret = PTR_ERR(hid_dev); 514 goto probe_err1; 515 } 516 517 hid_dev->ll_driver = &mousevsc_ll_driver; 518 hid_dev->driver = &mousevsc_hid_driver; 519 hid_dev->bus = BUS_VIRTUAL; 520 hid_dev->vendor = input_dev->hid_dev_info.vendor; 521 hid_dev->product = input_dev->hid_dev_info.product; 522 hid_dev->version = input_dev->hid_dev_info.version; 523 input_dev->hid_device = hid_dev; 524 525 sprintf(hid_dev->name, "%s", "Microsoft Vmbus HID-compliant Mouse"); 526 527 hid_set_drvdata(hid_dev, device); 528 529 ret = hid_add_device(hid_dev); 530 if (ret) 531 goto probe_err1; 532 533 534 ret = hid_parse(hid_dev); 535 if (ret) { 536 hid_err(hid_dev, "parse failed\n"); 537 goto probe_err2; 538 } 539 540 ret = hid_hw_start(hid_dev, HID_CONNECT_HIDINPUT | HID_CONNECT_HIDDEV); 541 542 if (ret) { 543 hid_err(hid_dev, "hw start failed\n"); 544 goto probe_err2; 545 } 546 547 device_init_wakeup(&device->device, true); 548 549 input_dev->connected = true; 550 input_dev->init_complete = true; 551 552 return ret; 553 554 probe_err2: 555 hid_destroy_device(hid_dev); 556 557 probe_err1: 558 vmbus_close(device->channel); 559 560 probe_err0: 561 mousevsc_free_device(input_dev); 562 563 return ret; 564 } 565 566 567 static int mousevsc_remove(struct hv_device *dev) 568 { 569 struct mousevsc_dev *input_dev = hv_get_drvdata(dev); 570 571 device_init_wakeup(&dev->device, false); 572 vmbus_close(dev->channel); 573 hid_hw_stop(input_dev->hid_device); 574 hid_destroy_device(input_dev->hid_device); 575 mousevsc_free_device(input_dev); 576 577 return 0; 578 } 579 580 static const struct hv_vmbus_device_id id_table[] = { 581 /* Mouse guid */ 582 { HV_MOUSE_GUID, }, 583 { }, 584 }; 585 586 MODULE_DEVICE_TABLE(vmbus, id_table); 587 588 static struct hv_driver mousevsc_drv = { 589 .name = KBUILD_MODNAME, 590 .id_table = id_table, 591 .probe = mousevsc_probe, 592 .remove = mousevsc_remove, 593 .driver = { 594 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 595 }, 596 }; 597 598 static int __init mousevsc_init(void) 599 { 600 return vmbus_driver_register(&mousevsc_drv); 601 } 602 603 static void __exit mousevsc_exit(void) 604 { 605 vmbus_driver_unregister(&mousevsc_drv); 606 } 607 608 MODULE_LICENSE("GPL"); 609 MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic HID Driver"); 610 611 module_init(mousevsc_init); 612 module_exit(mousevsc_exit); 613