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