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 #include <linux/kernel.h>
22 #include <linux/sched.h>
23 #include <linux/wait.h>
24 #include <linux/mm.h>
25 #include <linux/slab.h>
26 #include <linux/module.h>
27 #include "hv_api.h"
28 #include "logging.h"
29 #include "vmbus_private.h"
30 
31 #define NUM_PAGES_SPANNED(addr, len) \
32 ((PAGE_ALIGN(addr + len) >> PAGE_SHIFT) - (addr >> PAGE_SHIFT))
33 
34 /* Internal routines */
35 static int create_gpadl_header(
36 	void *kbuffer,	/* must be phys and virt contiguous */
37 	u32 size,	/* page-size multiple */
38 	struct vmbus_channel_msginfo **msginfo,
39 	u32 *messagecount);
40 static void dump_vmbus_channel(struct vmbus_channel *channel);
41 static void vmbus_setevent(struct vmbus_channel *channel);
42 
43 
44 #if 0
45 static void DumpMonitorPage(struct hv_monitor_page *MonitorPage)
46 {
47 	int i = 0;
48 	int j = 0;
49 
50 	DPRINT_DBG(VMBUS, "monitorPage - %p, trigger state - %d",
51 		   MonitorPage, MonitorPage->trigger_state);
52 
53 	for (i = 0; i < 4; i++)
54 		DPRINT_DBG(VMBUS, "trigger group (%d) - %llx", i,
55 			   MonitorPage->trigger_group[i].as_uint64);
56 
57 	for (i = 0; i < 4; i++) {
58 		for (j = 0; j < 32; j++) {
59 			DPRINT_DBG(VMBUS, "latency (%d)(%d) - %llx", i, j,
60 				   MonitorPage->latency[i][j]);
61 		}
62 	}
63 	for (i = 0; i < 4; i++) {
64 		for (j = 0; j < 32; j++) {
65 			DPRINT_DBG(VMBUS, "param-conn id (%d)(%d) - %d", i, j,
66 			       MonitorPage->parameter[i][j].connectionid.asu32);
67 			DPRINT_DBG(VMBUS, "param-flag (%d)(%d) - %d", i, j,
68 				MonitorPage->parameter[i][j].flag_number);
69 		}
70 	}
71 }
72 #endif
73 
74 /*
75  * vmbus_setevent- Trigger an event notification on the specified
76  * channel.
77  */
vmbus_setevent(struct vmbus_channel * channel)78 static void vmbus_setevent(struct vmbus_channel *channel)
79 {
80 	struct hv_monitor_page *monitorpage;
81 
82 	if (channel->offermsg.monitor_allocated) {
83 		/* Each u32 represents 32 channels */
84 		sync_set_bit(channel->offermsg.child_relid & 31,
85 			(unsigned long *) vmbus_connection.send_int_page +
86 			(channel->offermsg.child_relid >> 5));
87 
88 		monitorpage = vmbus_connection.monitor_pages;
89 		monitorpage++; /* Get the child to parent monitor page */
90 
91 		sync_set_bit(channel->monitor_bit,
92 			(unsigned long *)&monitorpage->trigger_group
93 					[channel->monitor_grp].pending);
94 
95 	} else {
96 		vmbus_set_event(channel->offermsg.child_relid);
97 	}
98 }
99 
100 #if 0
101 static void VmbusChannelClearEvent(struct vmbus_channel *channel)
102 {
103 	struct hv_monitor_page *monitorPage;
104 
105 	if (Channel->offermsg.monitor_allocated) {
106 		/* Each u32 represents 32 channels */
107 		sync_clear_bit(Channel->offermsg.child_relid & 31,
108 			  (unsigned long *)vmbus_connection.send_int_page +
109 			  (Channel->offermsg.child_relid >> 5));
110 
111 		monitorPage = (struct hv_monitor_page *)
112 			vmbus_connection.monitor_pages;
113 		monitorPage++; /* Get the child to parent monitor page */
114 
115 		sync_clear_bit(Channel->monitor_bit,
116 			  (unsigned long *)&monitorPage->trigger_group
117 					[Channel->monitor_grp].Pending);
118 	}
119 }
120 
121 #endif
122 /*
123  * vmbus_get_debug_info -Retrieve various channel debug info
124  */
vmbus_get_debug_info(struct vmbus_channel * channel,struct vmbus_channel_debug_info * debuginfo)125 void vmbus_get_debug_info(struct vmbus_channel *channel,
126 			      struct vmbus_channel_debug_info *debuginfo)
127 {
128 	struct hv_monitor_page *monitorpage;
129 	u8 monitor_group = (u8)channel->offermsg.monitorid / 32;
130 	u8 monitor_offset = (u8)channel->offermsg.monitorid % 32;
131 	/* u32 monitorBit	= 1 << monitorOffset; */
132 
133 	debuginfo->relid = channel->offermsg.child_relid;
134 	debuginfo->state = channel->state;
135 	memcpy(&debuginfo->interfacetype,
136 	       &channel->offermsg.offer.if_type, sizeof(struct hv_guid));
137 	memcpy(&debuginfo->interface_instance,
138 	       &channel->offermsg.offer.if_instance,
139 	       sizeof(struct hv_guid));
140 
141 	monitorpage = (struct hv_monitor_page *)vmbus_connection.monitor_pages;
142 
143 	debuginfo->monitorid = channel->offermsg.monitorid;
144 
145 	debuginfo->servermonitor_pending =
146 			monitorpage->trigger_group[monitor_group].pending;
147 	debuginfo->servermonitor_latency =
148 			monitorpage->latency[monitor_group][monitor_offset];
149 	debuginfo->servermonitor_connectionid =
150 			monitorpage->parameter[monitor_group]
151 					[monitor_offset].connectionid.u.id;
152 
153 	monitorpage++;
154 
155 	debuginfo->clientmonitor_pending =
156 			monitorpage->trigger_group[monitor_group].pending;
157 	debuginfo->clientmonitor_latency =
158 			monitorpage->latency[monitor_group][monitor_offset];
159 	debuginfo->clientmonitor_connectionid =
160 			monitorpage->parameter[monitor_group]
161 					[monitor_offset].connectionid.u.id;
162 
163 	ringbuffer_get_debuginfo(&channel->inbound, &debuginfo->inbound);
164 	ringbuffer_get_debuginfo(&channel->outbound, &debuginfo->outbound);
165 }
166 
167 /*
168  * vmbus_open - Open the specified channel.
169  */
vmbus_open(struct vmbus_channel * newchannel,u32 send_ringbuffer_size,u32 recv_ringbuffer_size,void * userdata,u32 userdatalen,void (* onchannelcallback)(void * context),void * context)170 int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size,
171 		     u32 recv_ringbuffer_size, void *userdata, u32 userdatalen,
172 		     void (*onchannelcallback)(void *context), void *context)
173 {
174 	struct vmbus_channel_open_channel *openMsg;
175 	struct vmbus_channel_msginfo *openInfo = NULL;
176 	void *in, *out;
177 	unsigned long flags;
178 	int ret, err = 0;
179 
180 	/* Aligned to page size */
181 	/* ASSERT(!(SendRingBufferSize & (PAGE_SIZE - 1))); */
182 	/* ASSERT(!(RecvRingBufferSize & (PAGE_SIZE - 1))); */
183 
184 	newchannel->onchannel_callback = onchannelcallback;
185 	newchannel->channel_callback_context = context;
186 
187 	/* Allocate the ring buffer */
188 	out = (void *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
189 		get_order(send_ringbuffer_size + recv_ringbuffer_size));
190 
191 	if (!out)
192 		return -ENOMEM;
193 
194 	/* ASSERT(((unsigned long)out & (PAGE_SIZE-1)) == 0); */
195 
196 	in = (void *)((unsigned long)out + send_ringbuffer_size);
197 
198 	newchannel->ringbuffer_pages = out;
199 	newchannel->ringbuffer_pagecount = (send_ringbuffer_size +
200 					   recv_ringbuffer_size) >> PAGE_SHIFT;
201 
202 	ret = ringbuffer_init(&newchannel->outbound, out, send_ringbuffer_size);
203 	if (ret != 0) {
204 		err = ret;
205 		goto errorout;
206 	}
207 
208 	ret = ringbuffer_init(&newchannel->inbound, in, recv_ringbuffer_size);
209 	if (ret != 0) {
210 		err = ret;
211 		goto errorout;
212 	}
213 
214 
215 	/* Establish the gpadl for the ring buffer */
216 	DPRINT_DBG(VMBUS, "Establishing ring buffer's gpadl for channel %p...",
217 		   newchannel);
218 
219 	newchannel->ringbuffer_gpadlhandle = 0;
220 
221 	ret = vmbus_establish_gpadl(newchannel,
222 					 newchannel->outbound.ring_buffer,
223 					 send_ringbuffer_size +
224 					 recv_ringbuffer_size,
225 					 &newchannel->ringbuffer_gpadlhandle);
226 
227 	if (ret != 0) {
228 		err = ret;
229 		goto errorout;
230 	}
231 
232 	DPRINT_DBG(VMBUS, "channel %p <relid %d gpadl 0x%x send ring %p "
233 		   "size %d recv ring %p size %d, downstreamoffset %d>",
234 		   newchannel, newchannel->offermsg.child_relid,
235 		   newchannel->ringbuffer_gpadlhandle,
236 		   newchannel->outbound.ring_buffer,
237 		   newchannel->outbound.ring_size,
238 		   newchannel->inbound.ring_buffer,
239 		   newchannel->inbound.ring_size,
240 		   send_ringbuffer_size);
241 
242 	/* Create and init the channel open message */
243 	openInfo = kmalloc(sizeof(*openInfo) +
244 			   sizeof(struct vmbus_channel_open_channel),
245 			   GFP_KERNEL);
246 	if (!openInfo) {
247 		err = -ENOMEM;
248 		goto errorout;
249 	}
250 
251 	init_waitqueue_head(&openInfo->waitevent);
252 
253 	openMsg = (struct vmbus_channel_open_channel *)openInfo->msg;
254 	openMsg->header.msgtype = CHANNELMSG_OPENCHANNEL;
255 	openMsg->openid = newchannel->offermsg.child_relid; /* FIXME */
256 	openMsg->child_relid = newchannel->offermsg.child_relid;
257 	openMsg->ringbuffer_gpadlhandle = newchannel->ringbuffer_gpadlhandle;
258 	openMsg->downstream_ringbuffer_pageoffset = send_ringbuffer_size >>
259 						  PAGE_SHIFT;
260 	openMsg->server_contextarea_gpadlhandle = 0; /* TODO */
261 
262 	if (userdatalen > MAX_USER_DEFINED_BYTES) {
263 		err = -EINVAL;
264 		goto errorout;
265 	}
266 
267 	if (userdatalen)
268 		memcpy(openMsg->userdata, userdata, userdatalen);
269 
270 	spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
271 	list_add_tail(&openInfo->msglistentry,
272 		      &vmbus_connection.chn_msg_list);
273 	spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
274 
275 	DPRINT_DBG(VMBUS, "Sending channel open msg...");
276 
277 	ret = vmbus_post_msg(openMsg,
278 			       sizeof(struct vmbus_channel_open_channel));
279 	if (ret != 0) {
280 		DPRINT_ERR(VMBUS, "unable to open channel - %d", ret);
281 		goto Cleanup;
282 	}
283 
284 	openInfo->wait_condition = 0;
285 	wait_event_timeout(openInfo->waitevent,
286 			openInfo->wait_condition,
287 			msecs_to_jiffies(1000));
288 	if (openInfo->wait_condition == 0) {
289 		err = -ETIMEDOUT;
290 		goto errorout;
291 	}
292 
293 
294 	if (openInfo->response.open_result.status == 0)
295 		DPRINT_INFO(VMBUS, "channel <%p> open success!!", newchannel);
296 	else
297 		DPRINT_INFO(VMBUS, "channel <%p> open failed - %d!!",
298 			    newchannel, openInfo->response.open_result.status);
299 
300 Cleanup:
301 	spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
302 	list_del(&openInfo->msglistentry);
303 	spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
304 
305 	kfree(openInfo);
306 	return 0;
307 
308 errorout:
309 	ringbuffer_cleanup(&newchannel->outbound);
310 	ringbuffer_cleanup(&newchannel->inbound);
311 	free_pages((unsigned long)out,
312 		get_order(send_ringbuffer_size + recv_ringbuffer_size));
313 	kfree(openInfo);
314 	return err;
315 }
316 EXPORT_SYMBOL_GPL(vmbus_open);
317 
318 /*
319  * dump_gpadl_body - Dump the gpadl body message to the console for
320  * debugging purposes.
321  */
dump_gpadl_body(struct vmbus_channel_gpadl_body * gpadl,u32 len)322 static void dump_gpadl_body(struct vmbus_channel_gpadl_body *gpadl, u32 len)
323 {
324 	int i;
325 	int pfncount;
326 
327 	pfncount = (len - sizeof(struct vmbus_channel_gpadl_body)) /
328 		   sizeof(u64);
329 	DPRINT_DBG(VMBUS, "gpadl body - len %d pfn count %d", len, pfncount);
330 
331 	for (i = 0; i < pfncount; i++)
332 		DPRINT_DBG(VMBUS, "gpadl body  - %d) pfn %llu",
333 			   i, gpadl->pfn[i]);
334 }
335 
336 /*
337  * dump_gpadl_header - Dump the gpadl header message to the console for
338  * debugging purposes.
339  */
dump_gpadl_header(struct vmbus_channel_gpadl_header * gpadl)340 static void dump_gpadl_header(struct vmbus_channel_gpadl_header *gpadl)
341 {
342 	int i, j;
343 	int pagecount;
344 
345 	DPRINT_DBG(VMBUS,
346 		   "gpadl header - relid %d, range count %d, range buflen %d",
347 		   gpadl->child_relid, gpadl->rangecount, gpadl->range_buflen);
348 	for (i = 0; i < gpadl->rangecount; i++) {
349 		pagecount = gpadl->range[i].byte_count >> PAGE_SHIFT;
350 		pagecount = (pagecount > 26) ? 26 : pagecount;
351 
352 		DPRINT_DBG(VMBUS, "gpadl range %d - len %d offset %d "
353 			   "page count %d", i, gpadl->range[i].byte_count,
354 			   gpadl->range[i].byte_offset, pagecount);
355 
356 		for (j = 0; j < pagecount; j++)
357 			DPRINT_DBG(VMBUS, "%d) pfn %llu", j,
358 				   gpadl->range[i].pfn_array[j]);
359 	}
360 }
361 
362 /*
363  * create_gpadl_header - Creates a gpadl for the specified buffer
364  */
create_gpadl_header(void * kbuffer,u32 size,struct vmbus_channel_msginfo ** msginfo,u32 * messagecount)365 static int create_gpadl_header(void *kbuffer, u32 size,
366 					 struct vmbus_channel_msginfo **msginfo,
367 					 u32 *messagecount)
368 {
369 	int i;
370 	int pagecount;
371 	unsigned long long pfn;
372 	struct vmbus_channel_gpadl_header *gpadl_header;
373 	struct vmbus_channel_gpadl_body *gpadl_body;
374 	struct vmbus_channel_msginfo *msgheader;
375 	struct vmbus_channel_msginfo *msgbody = NULL;
376 	u32 msgsize;
377 
378 	int pfnsum, pfncount, pfnleft, pfncurr, pfnsize;
379 
380 	/* ASSERT((kbuffer & (PAGE_SIZE-1)) == 0); */
381 	/* ASSERT((Size & (PAGE_SIZE-1)) == 0); */
382 
383 	pagecount = size >> PAGE_SHIFT;
384 	pfn = virt_to_phys(kbuffer) >> PAGE_SHIFT;
385 
386 	/* do we need a gpadl body msg */
387 	pfnsize = MAX_SIZE_CHANNEL_MESSAGE -
388 		  sizeof(struct vmbus_channel_gpadl_header) -
389 		  sizeof(struct gpa_range);
390 	pfncount = pfnsize / sizeof(u64);
391 
392 	if (pagecount > pfncount) {
393 		/* we need a gpadl body */
394 		/* fill in the header */
395 		msgsize = sizeof(struct vmbus_channel_msginfo) +
396 			  sizeof(struct vmbus_channel_gpadl_header) +
397 			  sizeof(struct gpa_range) + pfncount * sizeof(u64);
398 		msgheader =  kzalloc(msgsize, GFP_KERNEL);
399 		if (!msgheader)
400 			goto nomem;
401 
402 		INIT_LIST_HEAD(&msgheader->submsglist);
403 		msgheader->msgsize = msgsize;
404 
405 		gpadl_header = (struct vmbus_channel_gpadl_header *)
406 			msgheader->msg;
407 		gpadl_header->rangecount = 1;
408 		gpadl_header->range_buflen = sizeof(struct gpa_range) +
409 					 pagecount * sizeof(u64);
410 		gpadl_header->range[0].byte_offset = 0;
411 		gpadl_header->range[0].byte_count = size;
412 		for (i = 0; i < pfncount; i++)
413 			gpadl_header->range[0].pfn_array[i] = pfn+i;
414 		*msginfo = msgheader;
415 		*messagecount = 1;
416 
417 		pfnsum = pfncount;
418 		pfnleft = pagecount - pfncount;
419 
420 		/* how many pfns can we fit */
421 		pfnsize = MAX_SIZE_CHANNEL_MESSAGE -
422 			  sizeof(struct vmbus_channel_gpadl_body);
423 		pfncount = pfnsize / sizeof(u64);
424 
425 		/* fill in the body */
426 		while (pfnleft) {
427 			if (pfnleft > pfncount)
428 				pfncurr = pfncount;
429 			else
430 				pfncurr = pfnleft;
431 
432 			msgsize = sizeof(struct vmbus_channel_msginfo) +
433 				  sizeof(struct vmbus_channel_gpadl_body) +
434 				  pfncurr * sizeof(u64);
435 			msgbody = kzalloc(msgsize, GFP_KERNEL);
436 			/* FIXME: we probably need to more if this fails */
437 			if (!msgbody)
438 				goto nomem;
439 			msgbody->msgsize = msgsize;
440 			(*messagecount)++;
441 			gpadl_body =
442 				(struct vmbus_channel_gpadl_body *)msgbody->msg;
443 
444 			/*
445 			 * FIXME:
446 			 * Gpadl is u32 and we are using a pointer which could
447 			 * be 64-bit
448 			 */
449 			/* gpadl_body->Gpadl = kbuffer; */
450 			for (i = 0; i < pfncurr; i++)
451 				gpadl_body->pfn[i] = pfn + pfnsum + i;
452 
453 			/* add to msg header */
454 			list_add_tail(&msgbody->msglistentry,
455 				      &msgheader->submsglist);
456 			pfnsum += pfncurr;
457 			pfnleft -= pfncurr;
458 		}
459 	} else {
460 		/* everything fits in a header */
461 		msgsize = sizeof(struct vmbus_channel_msginfo) +
462 			  sizeof(struct vmbus_channel_gpadl_header) +
463 			  sizeof(struct gpa_range) + pagecount * sizeof(u64);
464 		msgheader = kzalloc(msgsize, GFP_KERNEL);
465 		if (msgheader == NULL)
466 			goto nomem;
467 		msgheader->msgsize = msgsize;
468 
469 		gpadl_header = (struct vmbus_channel_gpadl_header *)
470 			msgheader->msg;
471 		gpadl_header->rangecount = 1;
472 		gpadl_header->range_buflen = sizeof(struct gpa_range) +
473 					 pagecount * sizeof(u64);
474 		gpadl_header->range[0].byte_offset = 0;
475 		gpadl_header->range[0].byte_count = size;
476 		for (i = 0; i < pagecount; i++)
477 			gpadl_header->range[0].pfn_array[i] = pfn+i;
478 
479 		*msginfo = msgheader;
480 		*messagecount = 1;
481 	}
482 
483 	return 0;
484 nomem:
485 	kfree(msgheader);
486 	kfree(msgbody);
487 	return -ENOMEM;
488 }
489 
490 /*
491  * vmbus_establish_gpadl - Estabish a GPADL for the specified buffer
492  *
493  * @channel: a channel
494  * @kbuffer: from kmalloc
495  * @size: page-size multiple
496  * @gpadl_handle: some funky thing
497  */
vmbus_establish_gpadl(struct vmbus_channel * channel,void * kbuffer,u32 size,u32 * gpadl_handle)498 int vmbus_establish_gpadl(struct vmbus_channel *channel, void *kbuffer,
499 			       u32 size, u32 *gpadl_handle)
500 {
501 	struct vmbus_channel_gpadl_header *gpadlmsg;
502 	struct vmbus_channel_gpadl_body *gpadl_body;
503 	/* struct vmbus_channel_gpadl_created *gpadlCreated; */
504 	struct vmbus_channel_msginfo *msginfo = NULL;
505 	struct vmbus_channel_msginfo *submsginfo;
506 	u32 msgcount;
507 	struct list_head *curr;
508 	u32 next_gpadl_handle;
509 	unsigned long flags;
510 	int ret = 0;
511 
512 	next_gpadl_handle = atomic_read(&vmbus_connection.next_gpadl_handle);
513 	atomic_inc(&vmbus_connection.next_gpadl_handle);
514 
515 	ret = create_gpadl_header(kbuffer, size, &msginfo, &msgcount);
516 	if (ret)
517 		return ret;
518 
519 	init_waitqueue_head(&msginfo->waitevent);
520 
521 	gpadlmsg = (struct vmbus_channel_gpadl_header *)msginfo->msg;
522 	gpadlmsg->header.msgtype = CHANNELMSG_GPADL_HEADER;
523 	gpadlmsg->child_relid = channel->offermsg.child_relid;
524 	gpadlmsg->gpadl = next_gpadl_handle;
525 
526 	dump_gpadl_header(gpadlmsg);
527 
528 	spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
529 	list_add_tail(&msginfo->msglistentry,
530 		      &vmbus_connection.chn_msg_list);
531 
532 	spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
533 	DPRINT_DBG(VMBUS, "buffer %p, size %d msg cnt %d",
534 		   kbuffer, size, msgcount);
535 
536 	DPRINT_DBG(VMBUS, "Sending GPADL Header - len %zd",
537 		   msginfo->msgsize - sizeof(*msginfo));
538 
539 	msginfo->wait_condition = 0;
540 	ret = vmbus_post_msg(gpadlmsg, msginfo->msgsize -
541 			       sizeof(*msginfo));
542 	if (ret != 0) {
543 		DPRINT_ERR(VMBUS, "Unable to open channel - %d", ret);
544 		goto Cleanup;
545 	}
546 
547 	if (msgcount > 1) {
548 		list_for_each(curr, &msginfo->submsglist) {
549 
550 			/* FIXME: should this use list_entry() instead ? */
551 			submsginfo = (struct vmbus_channel_msginfo *)curr;
552 			gpadl_body =
553 			     (struct vmbus_channel_gpadl_body *)submsginfo->msg;
554 
555 			gpadl_body->header.msgtype =
556 				CHANNELMSG_GPADL_BODY;
557 			gpadl_body->gpadl = next_gpadl_handle;
558 
559 			DPRINT_DBG(VMBUS, "Sending GPADL Body - len %zd",
560 				   submsginfo->msgsize -
561 				   sizeof(*submsginfo));
562 
563 			dump_gpadl_body(gpadl_body, submsginfo->msgsize -
564 				      sizeof(*submsginfo));
565 			ret = vmbus_post_msg(gpadl_body,
566 					       submsginfo->msgsize -
567 					       sizeof(*submsginfo));
568 			if (ret != 0)
569 				goto Cleanup;
570 
571 		}
572 	}
573 	wait_event_timeout(msginfo->waitevent,
574 				msginfo->wait_condition,
575 				msecs_to_jiffies(1000));
576 	BUG_ON(msginfo->wait_condition == 0);
577 
578 
579 	/* At this point, we received the gpadl created msg */
580 	DPRINT_DBG(VMBUS, "Received GPADL created "
581 		   "(relid %d, status %d handle %x)",
582 		   channel->offermsg.child_relid,
583 		   msginfo->response.gpadl_created.creation_status,
584 		   gpadlmsg->gpadl);
585 
586 	*gpadl_handle = gpadlmsg->gpadl;
587 
588 Cleanup:
589 	spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
590 	list_del(&msginfo->msglistentry);
591 	spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
592 
593 	kfree(msginfo);
594 	return ret;
595 }
596 EXPORT_SYMBOL_GPL(vmbus_establish_gpadl);
597 
598 /*
599  * vmbus_teardown_gpadl -Teardown the specified GPADL handle
600  */
vmbus_teardown_gpadl(struct vmbus_channel * channel,u32 gpadl_handle)601 int vmbus_teardown_gpadl(struct vmbus_channel *channel, u32 gpadl_handle)
602 {
603 	struct vmbus_channel_gpadl_teardown *msg;
604 	struct vmbus_channel_msginfo *info;
605 	unsigned long flags;
606 	int ret;
607 
608 	/* ASSERT(gpadl_handle != 0); */
609 
610 	info = kmalloc(sizeof(*info) +
611 		       sizeof(struct vmbus_channel_gpadl_teardown), GFP_KERNEL);
612 	if (!info)
613 		return -ENOMEM;
614 
615 	init_waitqueue_head(&info->waitevent);
616 
617 	msg = (struct vmbus_channel_gpadl_teardown *)info->msg;
618 
619 	msg->header.msgtype = CHANNELMSG_GPADL_TEARDOWN;
620 	msg->child_relid = channel->offermsg.child_relid;
621 	msg->gpadl = gpadl_handle;
622 
623 	spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
624 	list_add_tail(&info->msglistentry,
625 		      &vmbus_connection.chn_msg_list);
626 	spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
627 	info->wait_condition = 0;
628 	ret = vmbus_post_msg(msg,
629 			       sizeof(struct vmbus_channel_gpadl_teardown));
630 
631 	BUG_ON(ret != 0);
632 	wait_event_timeout(info->waitevent,
633 			info->wait_condition, msecs_to_jiffies(1000));
634 	BUG_ON(info->wait_condition == 0);
635 
636 	/* Received a torndown response */
637 	spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
638 	list_del(&info->msglistentry);
639 	spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
640 
641 	kfree(info);
642 	return ret;
643 }
644 EXPORT_SYMBOL_GPL(vmbus_teardown_gpadl);
645 
646 /*
647  * vmbus_close - Close the specified channel
648  */
vmbus_close(struct vmbus_channel * channel)649 void vmbus_close(struct vmbus_channel *channel)
650 {
651 	struct vmbus_channel_close_channel *msg;
652 	struct vmbus_channel_msginfo *info;
653 	unsigned long flags;
654 	int ret;
655 
656 	/* Stop callback and cancel the timer asap */
657 	channel->onchannel_callback = NULL;
658 	del_timer_sync(&channel->poll_timer);
659 
660 	/* Send a closing message */
661 	info = kmalloc(sizeof(*info) +
662 		       sizeof(struct vmbus_channel_close_channel), GFP_KERNEL);
663         /* FIXME: can't do anything other than return here because the
664 	 *        function is void */
665 	if (!info)
666 		return;
667 
668 
669 	msg = (struct vmbus_channel_close_channel *)info->msg;
670 	msg->header.msgtype = CHANNELMSG_CLOSECHANNEL;
671 	msg->child_relid = channel->offermsg.child_relid;
672 
673 	ret = vmbus_post_msg(msg, sizeof(struct vmbus_channel_close_channel));
674 
675 	BUG_ON(ret != 0);
676 	/* Tear down the gpadl for the channel's ring buffer */
677 	if (channel->ringbuffer_gpadlhandle)
678 		vmbus_teardown_gpadl(channel,
679 					  channel->ringbuffer_gpadlhandle);
680 
681 	/* TODO: Send a msg to release the childRelId */
682 
683 	/* Cleanup the ring buffers for this channel */
684 	ringbuffer_cleanup(&channel->outbound);
685 	ringbuffer_cleanup(&channel->inbound);
686 
687 	free_pages((unsigned long)channel->ringbuffer_pages,
688 		get_order(channel->ringbuffer_pagecount * PAGE_SIZE));
689 
690 	kfree(info);
691 
692 	/*
693 	 * If we are closing the channel during an error path in
694 	 * opening the channel, don't free the channel since the
695 	 * caller will free the channel
696 	 */
697 
698 	if (channel->state == CHANNEL_OPEN_STATE) {
699 		spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
700 		list_del(&channel->listentry);
701 		spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
702 
703 		free_channel(channel);
704 	}
705 }
706 EXPORT_SYMBOL_GPL(vmbus_close);
707 
708 /**
709  * vmbus_sendpacket() - Send the specified buffer on the given channel
710  * @channel: Pointer to vmbus_channel structure.
711  * @buffer: Pointer to the buffer you want to receive the data into.
712  * @bufferlen: Maximum size of what the the buffer will hold
713  * @requestid: Identifier of the request
714  * @type: Type of packet that is being send e.g. negotiate, time
715  * packet etc.
716  *
717  * Sends data in @buffer directly to hyper-v via the vmbus
718  * This will send the data unparsed to hyper-v.
719  *
720  * Mainly used by Hyper-V drivers.
721  */
vmbus_sendpacket(struct vmbus_channel * channel,const void * buffer,u32 bufferlen,u64 requestid,enum vmbus_packet_type type,u32 flags)722 int vmbus_sendpacket(struct vmbus_channel *channel, const void *buffer,
723 			   u32 bufferlen, u64 requestid,
724 			   enum vmbus_packet_type type, u32 flags)
725 {
726 	struct vmpacket_descriptor desc;
727 	u32 packetlen = sizeof(struct vmpacket_descriptor) + bufferlen;
728 	u32 packetlen_aligned = ALIGN(packetlen, sizeof(u64));
729 	struct scatterlist bufferlist[3];
730 	u64 aligned_data = 0;
731 	int ret;
732 
733 	DPRINT_DBG(VMBUS, "channel %p buffer %p len %d",
734 		   channel, buffer, bufferlen);
735 
736 	dump_vmbus_channel(channel);
737 
738 	/* ASSERT((packetLenAligned - packetLen) < sizeof(u64)); */
739 
740 	/* Setup the descriptor */
741 	desc.type = type; /* VmbusPacketTypeDataInBand; */
742 	desc.flags = flags; /* VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED; */
743 	/* in 8-bytes granularity */
744 	desc.offset8 = sizeof(struct vmpacket_descriptor) >> 3;
745 	desc.len8 = (u16)(packetlen_aligned >> 3);
746 	desc.trans_id = requestid;
747 
748 	sg_init_table(bufferlist, 3);
749 	sg_set_buf(&bufferlist[0], &desc, sizeof(struct vmpacket_descriptor));
750 	sg_set_buf(&bufferlist[1], buffer, bufferlen);
751 	sg_set_buf(&bufferlist[2], &aligned_data,
752 		   packetlen_aligned - packetlen);
753 
754 	ret = ringbuffer_write(&channel->outbound, bufferlist, 3);
755 
756 	/* TODO: We should determine if this is optional */
757 	if (ret == 0 && !get_ringbuffer_interrupt_mask(&channel->outbound))
758 		vmbus_setevent(channel);
759 
760 	return ret;
761 }
762 EXPORT_SYMBOL(vmbus_sendpacket);
763 
764 /*
765  * vmbus_sendpacket_pagebuffer - Send a range of single-page buffer
766  * packets using a GPADL Direct packet type.
767  */
vmbus_sendpacket_pagebuffer(struct vmbus_channel * channel,struct hv_page_buffer pagebuffers[],u32 pagecount,void * buffer,u32 bufferlen,u64 requestid)768 int vmbus_sendpacket_pagebuffer(struct vmbus_channel *channel,
769 				     struct hv_page_buffer pagebuffers[],
770 				     u32 pagecount, void *buffer, u32 bufferlen,
771 				     u64 requestid)
772 {
773 	int ret;
774 	int i;
775 	struct vmbus_channel_packet_page_buffer desc;
776 	u32 descsize;
777 	u32 packetlen;
778 	u32 packetlen_aligned;
779 	struct scatterlist bufferlist[3];
780 	u64 aligned_data = 0;
781 
782 	if (pagecount > MAX_PAGE_BUFFER_COUNT)
783 		return -EINVAL;
784 
785 	dump_vmbus_channel(channel);
786 
787 	/*
788 	 * Adjust the size down since vmbus_channel_packet_page_buffer is the
789 	 * largest size we support
790 	 */
791 	descsize = sizeof(struct vmbus_channel_packet_page_buffer) -
792 			  ((MAX_PAGE_BUFFER_COUNT - pagecount) *
793 			  sizeof(struct hv_page_buffer));
794 	packetlen = descsize + bufferlen;
795 	packetlen_aligned = ALIGN(packetlen, sizeof(u64));
796 
797 	/* ASSERT((packetLenAligned - packetLen) < sizeof(u64)); */
798 
799 	/* Setup the descriptor */
800 	desc.type = VM_PKT_DATA_USING_GPA_DIRECT;
801 	desc.flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
802 	desc.dataoffset8 = descsize >> 3; /* in 8-bytes grandularity */
803 	desc.length8 = (u16)(packetlen_aligned >> 3);
804 	desc.transactionid = requestid;
805 	desc.rangecount = pagecount;
806 
807 	for (i = 0; i < pagecount; i++) {
808 		desc.range[i].len = pagebuffers[i].len;
809 		desc.range[i].offset = pagebuffers[i].offset;
810 		desc.range[i].pfn	 = pagebuffers[i].pfn;
811 	}
812 
813 	sg_init_table(bufferlist, 3);
814 	sg_set_buf(&bufferlist[0], &desc, descsize);
815 	sg_set_buf(&bufferlist[1], buffer, bufferlen);
816 	sg_set_buf(&bufferlist[2], &aligned_data,
817 		packetlen_aligned - packetlen);
818 
819 	ret = ringbuffer_write(&channel->outbound, bufferlist, 3);
820 
821 	/* TODO: We should determine if this is optional */
822 	if (ret == 0 && !get_ringbuffer_interrupt_mask(&channel->outbound))
823 		vmbus_setevent(channel);
824 
825 	return ret;
826 }
827 EXPORT_SYMBOL_GPL(vmbus_sendpacket_pagebuffer);
828 
829 /*
830  * vmbus_sendpacket_multipagebuffer - Send a multi-page buffer packet
831  * using a GPADL Direct packet type.
832  */
vmbus_sendpacket_multipagebuffer(struct vmbus_channel * channel,struct hv_multipage_buffer * multi_pagebuffer,void * buffer,u32 bufferlen,u64 requestid)833 int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel,
834 				struct hv_multipage_buffer *multi_pagebuffer,
835 				void *buffer, u32 bufferlen, u64 requestid)
836 {
837 	int ret;
838 	struct vmbus_channel_packet_multipage_buffer desc;
839 	u32 descsize;
840 	u32 packetlen;
841 	u32 packetlen_aligned;
842 	struct scatterlist bufferlist[3];
843 	u64 aligned_data = 0;
844 	u32 pfncount = NUM_PAGES_SPANNED(multi_pagebuffer->offset,
845 					 multi_pagebuffer->len);
846 
847 	dump_vmbus_channel(channel);
848 
849 	DPRINT_DBG(VMBUS, "data buffer - offset %u len %u pfn count %u",
850 		multi_pagebuffer->offset,
851 		multi_pagebuffer->len, pfncount);
852 
853 	if ((pfncount < 0) || (pfncount > MAX_MULTIPAGE_BUFFER_COUNT))
854 		return -EINVAL;
855 
856 	/*
857 	 * Adjust the size down since vmbus_channel_packet_multipage_buffer is
858 	 * the largest size we support
859 	 */
860 	descsize = sizeof(struct vmbus_channel_packet_multipage_buffer) -
861 			  ((MAX_MULTIPAGE_BUFFER_COUNT - pfncount) *
862 			  sizeof(u64));
863 	packetlen = descsize + bufferlen;
864 	packetlen_aligned = ALIGN(packetlen, sizeof(u64));
865 
866 	/* ASSERT((packetLenAligned - packetLen) < sizeof(u64)); */
867 
868 	/* Setup the descriptor */
869 	desc.type = VM_PKT_DATA_USING_GPA_DIRECT;
870 	desc.flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
871 	desc.dataoffset8 = descsize >> 3; /* in 8-bytes grandularity */
872 	desc.length8 = (u16)(packetlen_aligned >> 3);
873 	desc.transactionid = requestid;
874 	desc.rangecount = 1;
875 
876 	desc.range.len = multi_pagebuffer->len;
877 	desc.range.offset = multi_pagebuffer->offset;
878 
879 	memcpy(desc.range.pfn_array, multi_pagebuffer->pfn_array,
880 	       pfncount * sizeof(u64));
881 
882 	sg_init_table(bufferlist, 3);
883 	sg_set_buf(&bufferlist[0], &desc, descsize);
884 	sg_set_buf(&bufferlist[1], buffer, bufferlen);
885 	sg_set_buf(&bufferlist[2], &aligned_data,
886 		packetlen_aligned - packetlen);
887 
888 	ret = ringbuffer_write(&channel->outbound, bufferlist, 3);
889 
890 	/* TODO: We should determine if this is optional */
891 	if (ret == 0 && !get_ringbuffer_interrupt_mask(&channel->outbound))
892 		vmbus_setevent(channel);
893 
894 	return ret;
895 }
896 EXPORT_SYMBOL_GPL(vmbus_sendpacket_multipagebuffer);
897 
898 /**
899  * vmbus_recvpacket() - Retrieve the user packet on the specified channel
900  * @channel: Pointer to vmbus_channel structure.
901  * @buffer: Pointer to the buffer you want to receive the data into.
902  * @bufferlen: Maximum size of what the the buffer will hold
903  * @buffer_actual_len: The actual size of the data after it was received
904  * @requestid: Identifier of the request
905  *
906  * Receives directly from the hyper-v vmbus and puts the data it received
907  * into Buffer. This will receive the data unparsed from hyper-v.
908  *
909  * Mainly used by Hyper-V drivers.
910  */
vmbus_recvpacket(struct vmbus_channel * channel,void * buffer,u32 bufferlen,u32 * buffer_actual_len,u64 * requestid)911 int vmbus_recvpacket(struct vmbus_channel *channel, void *buffer,
912 			u32 bufferlen, u32 *buffer_actual_len, u64 *requestid)
913 {
914 	struct vmpacket_descriptor desc;
915 	u32 packetlen;
916 	u32 userlen;
917 	int ret;
918 	unsigned long flags;
919 
920 	*buffer_actual_len = 0;
921 	*requestid = 0;
922 
923 	spin_lock_irqsave(&channel->inbound_lock, flags);
924 
925 	ret = ringbuffer_peek(&channel->inbound, &desc,
926 			     sizeof(struct vmpacket_descriptor));
927 	if (ret != 0) {
928 		spin_unlock_irqrestore(&channel->inbound_lock, flags);
929 
930 		/* DPRINT_DBG(VMBUS, "nothing to read!!"); */
931 		return 0;
932 	}
933 
934 	/* VmbusChannelClearEvent(Channel); */
935 
936 	packetlen = desc.len8 << 3;
937 	userlen = packetlen - (desc.offset8 << 3);
938 	/* ASSERT(userLen > 0); */
939 
940 	DPRINT_DBG(VMBUS, "packet received on channel %p relid %d <type %d "
941 		   "flag %d tid %llx pktlen %d datalen %d> ",
942 		   channel, channel->offermsg.child_relid, desc.type,
943 		   desc.flags, desc.trans_id, packetlen, userlen);
944 
945 	*buffer_actual_len = userlen;
946 
947 	if (userlen > bufferlen) {
948 		spin_unlock_irqrestore(&channel->inbound_lock, flags);
949 
950 		DPRINT_ERR(VMBUS, "buffer too small - got %d needs %d",
951 			   bufferlen, userlen);
952 		return -1;
953 	}
954 
955 	*requestid = desc.trans_id;
956 
957 	/* Copy over the packet to the user buffer */
958 	ret = ringbuffer_read(&channel->inbound, buffer, userlen,
959 			     (desc.offset8 << 3));
960 
961 	spin_unlock_irqrestore(&channel->inbound_lock, flags);
962 
963 	return 0;
964 }
965 EXPORT_SYMBOL(vmbus_recvpacket);
966 
967 /*
968  * vmbus_recvpacket_raw - Retrieve the raw packet on the specified channel
969  */
vmbus_recvpacket_raw(struct vmbus_channel * channel,void * buffer,u32 bufferlen,u32 * buffer_actual_len,u64 * requestid)970 int vmbus_recvpacket_raw(struct vmbus_channel *channel, void *buffer,
971 			      u32 bufferlen, u32 *buffer_actual_len,
972 			      u64 *requestid)
973 {
974 	struct vmpacket_descriptor desc;
975 	u32 packetlen;
976 	u32 userlen;
977 	int ret;
978 	unsigned long flags;
979 
980 	*buffer_actual_len = 0;
981 	*requestid = 0;
982 
983 	spin_lock_irqsave(&channel->inbound_lock, flags);
984 
985 	ret = ringbuffer_peek(&channel->inbound, &desc,
986 			     sizeof(struct vmpacket_descriptor));
987 	if (ret != 0) {
988 		spin_unlock_irqrestore(&channel->inbound_lock, flags);
989 
990 		/* DPRINT_DBG(VMBUS, "nothing to read!!"); */
991 		return 0;
992 	}
993 
994 	/* VmbusChannelClearEvent(Channel); */
995 
996 	packetlen = desc.len8 << 3;
997 	userlen = packetlen - (desc.offset8 << 3);
998 
999 	DPRINT_DBG(VMBUS, "packet received on channel %p relid %d <type %d "
1000 		   "flag %d tid %llx pktlen %d datalen %d> ",
1001 		   channel, channel->offermsg.child_relid, desc.type,
1002 		   desc.flags, desc.trans_id, packetlen, userlen);
1003 
1004 	*buffer_actual_len = packetlen;
1005 
1006 	if (packetlen > bufferlen) {
1007 		spin_unlock_irqrestore(&channel->inbound_lock, flags);
1008 
1009 		DPRINT_ERR(VMBUS, "buffer too small - needed %d bytes but "
1010 			   "got space for only %d bytes", packetlen, bufferlen);
1011 		return -2;
1012 	}
1013 
1014 	*requestid = desc.trans_id;
1015 
1016 	/* Copy over the entire packet to the user buffer */
1017 	ret = ringbuffer_read(&channel->inbound, buffer, packetlen, 0);
1018 
1019 	spin_unlock_irqrestore(&channel->inbound_lock, flags);
1020 	return 0;
1021 }
1022 EXPORT_SYMBOL_GPL(vmbus_recvpacket_raw);
1023 
1024 /*
1025  * vmbus_onchannel_event - Channel event callback
1026  */
vmbus_onchannel_event(struct vmbus_channel * channel)1027 void vmbus_onchannel_event(struct vmbus_channel *channel)
1028 {
1029 	dump_vmbus_channel(channel);
1030 	/* ASSERT(Channel->OnChannelCallback); */
1031 
1032 	channel->onchannel_callback(channel->channel_callback_context);
1033 
1034 	mod_timer(&channel->poll_timer, jiffies + usecs_to_jiffies(100));
1035 }
1036 
1037 /*
1038  * vmbus_ontimer - Timer event callback
1039  */
vmbus_ontimer(unsigned long data)1040 void vmbus_ontimer(unsigned long data)
1041 {
1042 	struct vmbus_channel *channel = (struct vmbus_channel *)data;
1043 
1044 	if (channel->onchannel_callback)
1045 		channel->onchannel_callback(channel->channel_callback_context);
1046 }
1047 
1048 /*
1049  * dump_vmbus_channel- Dump vmbus channel info to the console
1050  */
dump_vmbus_channel(struct vmbus_channel * channel)1051 static void dump_vmbus_channel(struct vmbus_channel *channel)
1052 {
1053 	DPRINT_DBG(VMBUS, "Channel (%d)", channel->offermsg.child_relid);
1054 	dump_ring_info(&channel->outbound, "Outbound ");
1055 	dump_ring_info(&channel->inbound, "Inbound ");
1056 }
1057