1 /*
2 * Copyright (c) 2009, Microsoft Corporation.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
11 * more details.
12 *
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
15 * Place - Suite 330, Boston, MA 02111-1307 USA.
16 *
17 * Authors:
18 * Haiyang Zhang <haiyangz@microsoft.com>
19 * Hank Janssen <hjanssen@microsoft.com>
20 */
21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22
23 #include <linux/kernel.h>
24 #include <linux/sched.h>
25 #include <linux/wait.h>
26 #include <linux/mm.h>
27 #include <linux/slab.h>
28 #include <linux/list.h>
29 #include <linux/module.h>
30 #include <linux/completion.h>
31 #include <linux/hyperv.h>
32
33 #include "hyperv_vmbus.h"
34
35 struct vmbus_channel_message_table_entry {
36 enum vmbus_channel_message_type message_type;
37 void (*message_handler)(struct vmbus_channel_message_header *msg);
38 };
39
40
41 /**
42 * vmbus_prep_negotiate_resp() - Create default response for Hyper-V Negotiate message
43 * @icmsghdrp: Pointer to msg header structure
44 * @icmsg_negotiate: Pointer to negotiate message structure
45 * @buf: Raw buffer channel data
46 *
47 * @icmsghdrp is of type &struct icmsg_hdr.
48 * @negop is of type &struct icmsg_negotiate.
49 * Set up and fill in default negotiate response message. This response can
50 * come from both the vmbus driver and the hv_utils driver. The current api
51 * will respond properly to both Windows 2008 and Windows 2008-R2 operating
52 * systems.
53 *
54 * Mainly used by Hyper-V drivers.
55 */
vmbus_prep_negotiate_resp(struct icmsg_hdr * icmsghdrp,struct icmsg_negotiate * negop,u8 * buf)56 void vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp,
57 struct icmsg_negotiate *negop, u8 *buf)
58 {
59 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
60 icmsghdrp->icmsgsize = 0x10;
61
62 negop = (struct icmsg_negotiate *)&buf[
63 sizeof(struct vmbuspipe_hdr) +
64 sizeof(struct icmsg_hdr)];
65
66 if (negop->icframe_vercnt == 2 &&
67 negop->icversion_data[1].major == 3) {
68 negop->icversion_data[0].major = 3;
69 negop->icversion_data[0].minor = 0;
70 negop->icversion_data[1].major = 3;
71 negop->icversion_data[1].minor = 0;
72 } else {
73 negop->icversion_data[0].major = 1;
74 negop->icversion_data[0].minor = 0;
75 negop->icversion_data[1].major = 1;
76 negop->icversion_data[1].minor = 0;
77 }
78
79 negop->icframe_vercnt = 1;
80 negop->icmsg_vercnt = 1;
81 }
82 }
83 EXPORT_SYMBOL_GPL(vmbus_prep_negotiate_resp);
84
85 /*
86 * alloc_channel - Allocate and initialize a vmbus channel object
87 */
alloc_channel(void)88 static struct vmbus_channel *alloc_channel(void)
89 {
90 struct vmbus_channel *channel;
91
92 channel = kzalloc(sizeof(*channel), GFP_ATOMIC);
93 if (!channel)
94 return NULL;
95
96 spin_lock_init(&channel->inbound_lock);
97
98 channel->controlwq = create_workqueue("hv_vmbus_ctl");
99 if (!channel->controlwq) {
100 kfree(channel);
101 return NULL;
102 }
103
104 return channel;
105 }
106
107 /*
108 * release_hannel - Release the vmbus channel object itself
109 */
release_channel(struct work_struct * work)110 static void release_channel(struct work_struct *work)
111 {
112 struct vmbus_channel *channel = container_of(work,
113 struct vmbus_channel,
114 work);
115
116 destroy_workqueue(channel->controlwq);
117
118 kfree(channel);
119 }
120
121 /*
122 * free_channel - Release the resources used by the vmbus channel object
123 */
free_channel(struct vmbus_channel * channel)124 static void free_channel(struct vmbus_channel *channel)
125 {
126
127 /*
128 * We have to release the channel's workqueue/thread in the vmbus's
129 * workqueue/thread context
130 * ie we can't destroy ourselves.
131 */
132 INIT_WORK(&channel->work, release_channel);
133 queue_work(vmbus_connection.work_queue, &channel->work);
134 }
135
136
137
138 /*
139 * vmbus_process_rescind_offer -
140 * Rescind the offer by initiating a device removal
141 */
vmbus_process_rescind_offer(struct work_struct * work)142 static void vmbus_process_rescind_offer(struct work_struct *work)
143 {
144 struct vmbus_channel *channel = container_of(work,
145 struct vmbus_channel,
146 work);
147
148 vmbus_device_unregister(channel->device_obj);
149 }
150
vmbus_free_channels(void)151 void vmbus_free_channels(void)
152 {
153 struct vmbus_channel *channel;
154
155 list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
156 vmbus_device_unregister(channel->device_obj);
157 kfree(channel->device_obj);
158 free_channel(channel);
159 }
160 }
161
162 /*
163 * vmbus_process_offer - Process the offer by creating a channel/device
164 * associated with this offer
165 */
vmbus_process_offer(struct work_struct * work)166 static void vmbus_process_offer(struct work_struct *work)
167 {
168 struct vmbus_channel *newchannel = container_of(work,
169 struct vmbus_channel,
170 work);
171 struct vmbus_channel *channel;
172 bool fnew = true;
173 int ret;
174 unsigned long flags;
175
176 /* The next possible work is rescind handling */
177 INIT_WORK(&newchannel->work, vmbus_process_rescind_offer);
178
179 /* Make sure this is a new offer */
180 spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
181
182 list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
183 if (!uuid_le_cmp(channel->offermsg.offer.if_type,
184 newchannel->offermsg.offer.if_type) &&
185 !uuid_le_cmp(channel->offermsg.offer.if_instance,
186 newchannel->offermsg.offer.if_instance)) {
187 fnew = false;
188 break;
189 }
190 }
191
192 if (fnew)
193 list_add_tail(&newchannel->listentry,
194 &vmbus_connection.chn_list);
195
196 spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
197
198 if (!fnew) {
199 free_channel(newchannel);
200 return;
201 }
202
203 /*
204 * Start the process of binding this offer to the driver
205 * We need to set the DeviceObject field before calling
206 * vmbus_child_dev_add()
207 */
208 newchannel->device_obj = vmbus_device_create(
209 &newchannel->offermsg.offer.if_type,
210 &newchannel->offermsg.offer.if_instance,
211 newchannel);
212
213 /*
214 * Add the new device to the bus. This will kick off device-driver
215 * binding which eventually invokes the device driver's AddDevice()
216 * method.
217 */
218 ret = vmbus_device_register(newchannel->device_obj);
219 if (ret != 0) {
220 pr_err("unable to add child device object (relid %d)\n",
221 newchannel->offermsg.child_relid);
222
223 spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
224 list_del(&newchannel->listentry);
225 spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
226 kfree(newchannel->device_obj);
227
228 free_channel(newchannel);
229 } else {
230 /*
231 * This state is used to indicate a successful open
232 * so that when we do close the channel normally, we
233 * can cleanup properly
234 */
235 newchannel->state = CHANNEL_OPEN_STATE;
236 }
237 }
238
239 /*
240 * vmbus_onoffer - Handler for channel offers from vmbus in parent partition.
241 *
242 */
vmbus_onoffer(struct vmbus_channel_message_header * hdr)243 static void vmbus_onoffer(struct vmbus_channel_message_header *hdr)
244 {
245 struct vmbus_channel_offer_channel *offer;
246 struct vmbus_channel *newchannel;
247 uuid_le *guidtype;
248 uuid_le *guidinstance;
249
250 offer = (struct vmbus_channel_offer_channel *)hdr;
251
252 guidtype = &offer->offer.if_type;
253 guidinstance = &offer->offer.if_instance;
254
255 /* Allocate the channel object and save this offer. */
256 newchannel = alloc_channel();
257 if (!newchannel) {
258 pr_err("Unable to allocate channel object\n");
259 return;
260 }
261
262 memcpy(&newchannel->offermsg, offer,
263 sizeof(struct vmbus_channel_offer_channel));
264 newchannel->monitor_grp = (u8)offer->monitorid / 32;
265 newchannel->monitor_bit = (u8)offer->monitorid % 32;
266
267 INIT_WORK(&newchannel->work, vmbus_process_offer);
268 queue_work(newchannel->controlwq, &newchannel->work);
269 }
270
271 /*
272 * vmbus_onoffer_rescind - Rescind offer handler.
273 *
274 * We queue a work item to process this offer synchronously
275 */
vmbus_onoffer_rescind(struct vmbus_channel_message_header * hdr)276 static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
277 {
278 struct vmbus_channel_rescind_offer *rescind;
279 struct vmbus_channel *channel;
280
281 rescind = (struct vmbus_channel_rescind_offer *)hdr;
282 channel = relid2channel(rescind->child_relid);
283
284 if (channel == NULL)
285 /* Just return here, no channel found */
286 return;
287
288 /* work is initialized for vmbus_process_rescind_offer() from
289 * vmbus_process_offer() where the channel got created */
290 queue_work(channel->controlwq, &channel->work);
291 }
292
293 /*
294 * vmbus_onoffers_delivered -
295 * This is invoked when all offers have been delivered.
296 *
297 * Nothing to do here.
298 */
vmbus_onoffers_delivered(struct vmbus_channel_message_header * hdr)299 static void vmbus_onoffers_delivered(
300 struct vmbus_channel_message_header *hdr)
301 {
302 }
303
304 /*
305 * vmbus_onopen_result - Open result handler.
306 *
307 * This is invoked when we received a response to our channel open request.
308 * Find the matching request, copy the response and signal the requesting
309 * thread.
310 */
vmbus_onopen_result(struct vmbus_channel_message_header * hdr)311 static void vmbus_onopen_result(struct vmbus_channel_message_header *hdr)
312 {
313 struct vmbus_channel_open_result *result;
314 struct vmbus_channel_msginfo *msginfo;
315 struct vmbus_channel_message_header *requestheader;
316 struct vmbus_channel_open_channel *openmsg;
317 unsigned long flags;
318
319 result = (struct vmbus_channel_open_result *)hdr;
320
321 /*
322 * Find the open msg, copy the result and signal/unblock the wait event
323 */
324 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
325
326 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
327 msglistentry) {
328 requestheader =
329 (struct vmbus_channel_message_header *)msginfo->msg;
330
331 if (requestheader->msgtype == CHANNELMSG_OPENCHANNEL) {
332 openmsg =
333 (struct vmbus_channel_open_channel *)msginfo->msg;
334 if (openmsg->child_relid == result->child_relid &&
335 openmsg->openid == result->openid) {
336 memcpy(&msginfo->response.open_result,
337 result,
338 sizeof(
339 struct vmbus_channel_open_result));
340 complete(&msginfo->waitevent);
341 break;
342 }
343 }
344 }
345 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
346 }
347
348 /*
349 * vmbus_ongpadl_created - GPADL created handler.
350 *
351 * This is invoked when we received a response to our gpadl create request.
352 * Find the matching request, copy the response and signal the requesting
353 * thread.
354 */
vmbus_ongpadl_created(struct vmbus_channel_message_header * hdr)355 static void vmbus_ongpadl_created(struct vmbus_channel_message_header *hdr)
356 {
357 struct vmbus_channel_gpadl_created *gpadlcreated;
358 struct vmbus_channel_msginfo *msginfo;
359 struct vmbus_channel_message_header *requestheader;
360 struct vmbus_channel_gpadl_header *gpadlheader;
361 unsigned long flags;
362
363 gpadlcreated = (struct vmbus_channel_gpadl_created *)hdr;
364
365 /*
366 * Find the establish msg, copy the result and signal/unblock the wait
367 * event
368 */
369 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
370
371 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
372 msglistentry) {
373 requestheader =
374 (struct vmbus_channel_message_header *)msginfo->msg;
375
376 if (requestheader->msgtype == CHANNELMSG_GPADL_HEADER) {
377 gpadlheader =
378 (struct vmbus_channel_gpadl_header *)requestheader;
379
380 if ((gpadlcreated->child_relid ==
381 gpadlheader->child_relid) &&
382 (gpadlcreated->gpadl == gpadlheader->gpadl)) {
383 memcpy(&msginfo->response.gpadl_created,
384 gpadlcreated,
385 sizeof(
386 struct vmbus_channel_gpadl_created));
387 complete(&msginfo->waitevent);
388 break;
389 }
390 }
391 }
392 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
393 }
394
395 /*
396 * vmbus_ongpadl_torndown - GPADL torndown handler.
397 *
398 * This is invoked when we received a response to our gpadl teardown request.
399 * Find the matching request, copy the response and signal the requesting
400 * thread.
401 */
vmbus_ongpadl_torndown(struct vmbus_channel_message_header * hdr)402 static void vmbus_ongpadl_torndown(
403 struct vmbus_channel_message_header *hdr)
404 {
405 struct vmbus_channel_gpadl_torndown *gpadl_torndown;
406 struct vmbus_channel_msginfo *msginfo;
407 struct vmbus_channel_message_header *requestheader;
408 struct vmbus_channel_gpadl_teardown *gpadl_teardown;
409 unsigned long flags;
410
411 gpadl_torndown = (struct vmbus_channel_gpadl_torndown *)hdr;
412
413 /*
414 * Find the open msg, copy the result and signal/unblock the wait event
415 */
416 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
417
418 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
419 msglistentry) {
420 requestheader =
421 (struct vmbus_channel_message_header *)msginfo->msg;
422
423 if (requestheader->msgtype == CHANNELMSG_GPADL_TEARDOWN) {
424 gpadl_teardown =
425 (struct vmbus_channel_gpadl_teardown *)requestheader;
426
427 if (gpadl_torndown->gpadl == gpadl_teardown->gpadl) {
428 memcpy(&msginfo->response.gpadl_torndown,
429 gpadl_torndown,
430 sizeof(
431 struct vmbus_channel_gpadl_torndown));
432 complete(&msginfo->waitevent);
433 break;
434 }
435 }
436 }
437 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
438 }
439
440 /*
441 * vmbus_onversion_response - Version response handler
442 *
443 * This is invoked when we received a response to our initiate contact request.
444 * Find the matching request, copy the response and signal the requesting
445 * thread.
446 */
vmbus_onversion_response(struct vmbus_channel_message_header * hdr)447 static void vmbus_onversion_response(
448 struct vmbus_channel_message_header *hdr)
449 {
450 struct vmbus_channel_msginfo *msginfo;
451 struct vmbus_channel_message_header *requestheader;
452 struct vmbus_channel_initiate_contact *initiate;
453 struct vmbus_channel_version_response *version_response;
454 unsigned long flags;
455
456 version_response = (struct vmbus_channel_version_response *)hdr;
457 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
458
459 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
460 msglistentry) {
461 requestheader =
462 (struct vmbus_channel_message_header *)msginfo->msg;
463
464 if (requestheader->msgtype ==
465 CHANNELMSG_INITIATE_CONTACT) {
466 initiate =
467 (struct vmbus_channel_initiate_contact *)requestheader;
468 memcpy(&msginfo->response.version_response,
469 version_response,
470 sizeof(struct vmbus_channel_version_response));
471 complete(&msginfo->waitevent);
472 }
473 }
474 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
475 }
476
477 /* Channel message dispatch table */
478 static struct vmbus_channel_message_table_entry
479 channel_message_table[CHANNELMSG_COUNT] = {
480 {CHANNELMSG_INVALID, NULL},
481 {CHANNELMSG_OFFERCHANNEL, vmbus_onoffer},
482 {CHANNELMSG_RESCIND_CHANNELOFFER, vmbus_onoffer_rescind},
483 {CHANNELMSG_REQUESTOFFERS, NULL},
484 {CHANNELMSG_ALLOFFERS_DELIVERED, vmbus_onoffers_delivered},
485 {CHANNELMSG_OPENCHANNEL, NULL},
486 {CHANNELMSG_OPENCHANNEL_RESULT, vmbus_onopen_result},
487 {CHANNELMSG_CLOSECHANNEL, NULL},
488 {CHANNELMSG_GPADL_HEADER, NULL},
489 {CHANNELMSG_GPADL_BODY, NULL},
490 {CHANNELMSG_GPADL_CREATED, vmbus_ongpadl_created},
491 {CHANNELMSG_GPADL_TEARDOWN, NULL},
492 {CHANNELMSG_GPADL_TORNDOWN, vmbus_ongpadl_torndown},
493 {CHANNELMSG_RELID_RELEASED, NULL},
494 {CHANNELMSG_INITIATE_CONTACT, NULL},
495 {CHANNELMSG_VERSION_RESPONSE, vmbus_onversion_response},
496 {CHANNELMSG_UNLOAD, NULL},
497 };
498
499 /*
500 * vmbus_onmessage - Handler for channel protocol messages.
501 *
502 * This is invoked in the vmbus worker thread context.
503 */
vmbus_onmessage(void * context)504 void vmbus_onmessage(void *context)
505 {
506 struct hv_message *msg = context;
507 struct vmbus_channel_message_header *hdr;
508 int size;
509
510 hdr = (struct vmbus_channel_message_header *)msg->u.payload;
511 size = msg->header.payload_size;
512
513 if (hdr->msgtype >= CHANNELMSG_COUNT) {
514 pr_err("Received invalid channel message type %d size %d\n",
515 hdr->msgtype, size);
516 print_hex_dump_bytes("", DUMP_PREFIX_NONE,
517 (unsigned char *)msg->u.payload, size);
518 return;
519 }
520
521 if (channel_message_table[hdr->msgtype].message_handler)
522 channel_message_table[hdr->msgtype].message_handler(hdr);
523 else
524 pr_err("Unhandled channel message type %d\n", hdr->msgtype);
525 }
526
527 /*
528 * vmbus_request_offers - Send a request to get all our pending offers.
529 */
vmbus_request_offers(void)530 int vmbus_request_offers(void)
531 {
532 struct vmbus_channel_message_header *msg;
533 struct vmbus_channel_msginfo *msginfo;
534 int ret, t;
535
536 msginfo = kmalloc(sizeof(*msginfo) +
537 sizeof(struct vmbus_channel_message_header),
538 GFP_KERNEL);
539 if (!msginfo)
540 return -ENOMEM;
541
542 init_completion(&msginfo->waitevent);
543
544 msg = (struct vmbus_channel_message_header *)msginfo->msg;
545
546 msg->msgtype = CHANNELMSG_REQUESTOFFERS;
547
548
549 ret = vmbus_post_msg(msg,
550 sizeof(struct vmbus_channel_message_header));
551 if (ret != 0) {
552 pr_err("Unable to request offers - %d\n", ret);
553
554 goto cleanup;
555 }
556
557 t = wait_for_completion_timeout(&msginfo->waitevent, 5*HZ);
558 if (t == 0) {
559 ret = -ETIMEDOUT;
560 goto cleanup;
561 }
562
563
564
565 cleanup:
566 kfree(msginfo);
567
568 return ret;
569 }
570
571 /* eof */
572