vmbus_chan.c revision 300102
1/*-
2 * Copyright (c) 2009-2012,2016 Microsoft Corp.
3 * Copyright (c) 2012 NetApp Inc.
4 * Copyright (c) 2012 Citrix Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice unmodified, this list of conditions, and the following
12 *    disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD: head/sys/dev/hyperv/vmbus/hv_channel.c 300102 2016-05-18 03:19:53Z sephe $");
31
32#include <sys/param.h>
33#include <sys/kernel.h>
34#include <sys/malloc.h>
35#include <sys/systm.h>
36#include <sys/mbuf.h>
37#include <sys/lock.h>
38#include <sys/mutex.h>
39#include <sys/sysctl.h>
40#include <machine/bus.h>
41#include <vm/vm.h>
42#include <vm/vm_param.h>
43#include <vm/pmap.h>
44
45#include <dev/hyperv/vmbus/hv_vmbus_priv.h>
46#include <dev/hyperv/vmbus/vmbus_var.h>
47
48static int 	vmbus_channel_create_gpadl_header(
49			/* must be phys and virt contiguous*/
50			void*				contig_buffer,
51			/* page-size multiple */
52			uint32_t 			size,
53			hv_vmbus_channel_msg_info**	msg_info,
54			uint32_t*			message_count);
55
56static void 	vmbus_channel_set_event(hv_vmbus_channel* channel);
57static void	VmbusProcessChannelEvent(void* channel, int pending);
58
59/**
60 *  @brief Trigger an event notification on the specified channel
61 */
62static void
63vmbus_channel_set_event(hv_vmbus_channel *channel)
64{
65	hv_vmbus_monitor_page *monitor_page;
66
67	if (channel->offer_msg.monitor_allocated) {
68		/* Each uint32_t represents 32 channels */
69		synch_set_bit((channel->offer_msg.child_rel_id & 31),
70			((uint32_t *)hv_vmbus_g_connection.send_interrupt_page
71				+ ((channel->offer_msg.child_rel_id >> 5))));
72
73		monitor_page = (hv_vmbus_monitor_page *)
74			hv_vmbus_g_connection.monitor_page_2;
75
76		synch_set_bit(channel->monitor_bit,
77			(uint32_t *)&monitor_page->
78				trigger_group[channel->monitor_group].u.pending);
79	} else {
80		hv_vmbus_set_event(channel);
81	}
82
83}
84
85static int
86vmbus_channel_sysctl_monalloc(SYSCTL_HANDLER_ARGS)
87{
88	struct hv_vmbus_channel *chan = arg1;
89	int alloc = 0;
90
91	if (chan->offer_msg.monitor_allocated)
92		alloc = 1;
93	return sysctl_handle_int(oidp, &alloc, 0, req);
94}
95
96static void
97vmbus_channel_sysctl_create(hv_vmbus_channel* channel)
98{
99	device_t dev;
100	struct sysctl_oid *devch_sysctl;
101	struct sysctl_oid *devch_id_sysctl, *devch_sub_sysctl;
102	struct sysctl_oid *devch_id_in_sysctl, *devch_id_out_sysctl;
103	struct sysctl_ctx_list *ctx;
104	uint32_t ch_id;
105	uint16_t sub_ch_id;
106	char name[16];
107
108	hv_vmbus_channel* primary_ch = channel->primary_channel;
109
110	if (primary_ch == NULL) {
111		dev = channel->device->device;
112		ch_id = channel->offer_msg.child_rel_id;
113	} else {
114		dev = primary_ch->device->device;
115		ch_id = primary_ch->offer_msg.child_rel_id;
116		sub_ch_id = channel->offer_msg.offer.sub_channel_index;
117	}
118	ctx = device_get_sysctl_ctx(dev);
119	/* This creates dev.DEVNAME.DEVUNIT.channel tree */
120	devch_sysctl = SYSCTL_ADD_NODE(ctx,
121		    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
122		    OID_AUTO, "channel", CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "");
123	/* This creates dev.DEVNAME.DEVUNIT.channel.CHANID tree */
124	snprintf(name, sizeof(name), "%d", ch_id);
125	devch_id_sysctl = SYSCTL_ADD_NODE(ctx,
126	    	    SYSCTL_CHILDREN(devch_sysctl),
127	    	    OID_AUTO, name, CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "");
128
129	if (primary_ch != NULL) {
130		devch_sub_sysctl = SYSCTL_ADD_NODE(ctx,
131			SYSCTL_CHILDREN(devch_id_sysctl),
132			OID_AUTO, "sub", CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "");
133		snprintf(name, sizeof(name), "%d", sub_ch_id);
134		devch_id_sysctl = SYSCTL_ADD_NODE(ctx,
135			SYSCTL_CHILDREN(devch_sub_sysctl),
136			OID_AUTO, name, CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "");
137
138		SYSCTL_ADD_UINT(ctx, SYSCTL_CHILDREN(devch_id_sysctl),
139		    OID_AUTO, "chanid", CTLFLAG_RD,
140		    &channel->offer_msg.child_rel_id, 0, "channel id");
141	}
142	SYSCTL_ADD_UINT(ctx, SYSCTL_CHILDREN(devch_id_sysctl), OID_AUTO,
143	    "cpu", CTLFLAG_RD, &channel->target_cpu, 0, "owner CPU id");
144	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(devch_id_sysctl), OID_AUTO,
145	    "monitor_allocated", CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE,
146	    channel, 0, vmbus_channel_sysctl_monalloc, "I",
147	    "is monitor allocated to this channel");
148
149	devch_id_in_sysctl = SYSCTL_ADD_NODE(ctx,
150                    SYSCTL_CHILDREN(devch_id_sysctl),
151                    OID_AUTO,
152		    "in",
153		    CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "");
154	devch_id_out_sysctl = SYSCTL_ADD_NODE(ctx,
155                    SYSCTL_CHILDREN(devch_id_sysctl),
156                    OID_AUTO,
157		    "out",
158		    CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "");
159	hv_ring_buffer_stat(ctx,
160		SYSCTL_CHILDREN(devch_id_in_sysctl),
161		&(channel->inbound),
162		"inbound ring buffer stats");
163	hv_ring_buffer_stat(ctx,
164		SYSCTL_CHILDREN(devch_id_out_sysctl),
165		&(channel->outbound),
166		"outbound ring buffer stats");
167}
168
169/**
170 * @brief Open the specified channel
171 */
172int
173hv_vmbus_channel_open(
174	hv_vmbus_channel*		new_channel,
175	uint32_t			send_ring_buffer_size,
176	uint32_t			recv_ring_buffer_size,
177	void*				user_data,
178	uint32_t			user_data_len,
179	hv_vmbus_pfn_channel_callback	pfn_on_channel_callback,
180	void* 				context)
181{
182
183	int ret = 0;
184	void *in, *out;
185	hv_vmbus_channel_open_channel*	open_msg;
186	hv_vmbus_channel_msg_info* 	open_info;
187
188	mtx_lock(&new_channel->sc_lock);
189	if (new_channel->state == HV_CHANNEL_OPEN_STATE) {
190	    new_channel->state = HV_CHANNEL_OPENING_STATE;
191	} else {
192	    mtx_unlock(&new_channel->sc_lock);
193	    if(bootverbose)
194		printf("VMBUS: Trying to open channel <%p> which in "
195		    "%d state.\n", new_channel, new_channel->state);
196	    return (EINVAL);
197	}
198	mtx_unlock(&new_channel->sc_lock);
199
200	new_channel->on_channel_callback = pfn_on_channel_callback;
201	new_channel->channel_callback_context = context;
202
203	vmbus_on_channel_open(new_channel);
204
205	new_channel->rxq = hv_vmbus_g_context.hv_event_queue[new_channel->target_cpu];
206	TASK_INIT(&new_channel->channel_task, 0, VmbusProcessChannelEvent, new_channel);
207
208	/* Allocate the ring buffer */
209	out = contigmalloc((send_ring_buffer_size + recv_ring_buffer_size),
210	    M_DEVBUF, M_ZERO, 0UL, BUS_SPACE_MAXADDR, PAGE_SIZE, 0);
211	KASSERT(out != NULL,
212	    ("Error VMBUS: contigmalloc failed to allocate Ring Buffer!"));
213	if (out == NULL)
214		return (ENOMEM);
215
216	in = ((uint8_t *) out + send_ring_buffer_size);
217
218	new_channel->ring_buffer_pages = out;
219	new_channel->ring_buffer_page_count = (send_ring_buffer_size +
220	    recv_ring_buffer_size) >> PAGE_SHIFT;
221	new_channel->ring_buffer_size = send_ring_buffer_size +
222	    recv_ring_buffer_size;
223
224	hv_vmbus_ring_buffer_init(
225		&new_channel->outbound,
226		out,
227		send_ring_buffer_size);
228
229	hv_vmbus_ring_buffer_init(
230		&new_channel->inbound,
231		in,
232		recv_ring_buffer_size);
233
234	/* Create sysctl tree for this channel */
235	vmbus_channel_sysctl_create(new_channel);
236
237	/**
238	 * Establish the gpadl for the ring buffer
239	 */
240	new_channel->ring_buffer_gpadl_handle = 0;
241
242	ret = hv_vmbus_channel_establish_gpadl(new_channel,
243		new_channel->outbound.ring_buffer,
244		send_ring_buffer_size + recv_ring_buffer_size,
245		&new_channel->ring_buffer_gpadl_handle);
246
247	/**
248	 * Create and init the channel open message
249	 */
250	open_info = (hv_vmbus_channel_msg_info*) malloc(
251		sizeof(hv_vmbus_channel_msg_info) +
252			sizeof(hv_vmbus_channel_open_channel),
253		M_DEVBUF,
254		M_NOWAIT);
255	KASSERT(open_info != NULL,
256	    ("Error VMBUS: malloc failed to allocate Open Channel message!"));
257
258	if (open_info == NULL)
259		return (ENOMEM);
260
261	sema_init(&open_info->wait_sema, 0, "Open Info Sema");
262
263	open_msg = (hv_vmbus_channel_open_channel*) open_info->msg;
264	open_msg->header.message_type = HV_CHANNEL_MESSAGE_OPEN_CHANNEL;
265	open_msg->open_id = new_channel->offer_msg.child_rel_id;
266	open_msg->child_rel_id = new_channel->offer_msg.child_rel_id;
267	open_msg->ring_buffer_gpadl_handle =
268		new_channel->ring_buffer_gpadl_handle;
269	open_msg->downstream_ring_buffer_page_offset = send_ring_buffer_size
270		>> PAGE_SHIFT;
271	open_msg->target_vcpu = new_channel->target_vcpu;
272
273	if (user_data_len)
274		memcpy(open_msg->user_data, user_data, user_data_len);
275
276	mtx_lock(&hv_vmbus_g_connection.channel_msg_lock);
277	TAILQ_INSERT_TAIL(
278		&hv_vmbus_g_connection.channel_msg_anchor,
279		open_info,
280		msg_list_entry);
281	mtx_unlock(&hv_vmbus_g_connection.channel_msg_lock);
282
283	ret = hv_vmbus_post_message(
284		open_msg, sizeof(hv_vmbus_channel_open_channel));
285
286	if (ret != 0)
287	    goto cleanup;
288
289	ret = sema_timedwait(&open_info->wait_sema, 5 * hz); /* KYS 5 seconds */
290
291	if (ret) {
292	    if(bootverbose)
293		printf("VMBUS: channel <%p> open timeout.\n", new_channel);
294	    goto cleanup;
295	}
296
297	if (open_info->response.open_result.status == 0) {
298	    new_channel->state = HV_CHANNEL_OPENED_STATE;
299	    if(bootverbose)
300		printf("VMBUS: channel <%p> open success.\n", new_channel);
301	} else {
302	    if(bootverbose)
303		printf("Error VMBUS: channel <%p> open failed - %d!\n",
304			new_channel, open_info->response.open_result.status);
305	}
306
307	cleanup:
308	mtx_lock(&hv_vmbus_g_connection.channel_msg_lock);
309	TAILQ_REMOVE(
310		&hv_vmbus_g_connection.channel_msg_anchor,
311		open_info,
312		msg_list_entry);
313	mtx_unlock(&hv_vmbus_g_connection.channel_msg_lock);
314	sema_destroy(&open_info->wait_sema);
315	free(open_info, M_DEVBUF);
316
317	return (ret);
318}
319
320/**
321 * @brief Create a gpadl for the specified buffer
322 */
323static int
324vmbus_channel_create_gpadl_header(
325	void*				contig_buffer,
326	uint32_t			size,	/* page-size multiple */
327	hv_vmbus_channel_msg_info**	msg_info,
328	uint32_t*			message_count)
329{
330	int				i;
331	int				page_count;
332	unsigned long long 		pfn;
333	uint32_t			msg_size;
334	hv_vmbus_channel_gpadl_header*	gpa_header;
335	hv_vmbus_channel_gpadl_body*	gpadl_body;
336	hv_vmbus_channel_msg_info*	msg_header;
337	hv_vmbus_channel_msg_info*	msg_body;
338
339	int pfnSum, pfnCount, pfnLeft, pfnCurr, pfnSize;
340
341	page_count = size >> PAGE_SHIFT;
342	pfn = hv_get_phys_addr(contig_buffer) >> PAGE_SHIFT;
343
344	/*do we need a gpadl body msg */
345	pfnSize = HV_MAX_SIZE_CHANNEL_MESSAGE
346	    - sizeof(hv_vmbus_channel_gpadl_header)
347	    - sizeof(hv_gpa_range);
348	pfnCount = pfnSize / sizeof(uint64_t);
349
350	if (page_count > pfnCount) { /* if(we need a gpadl body)	*/
351	    /* fill in the header		*/
352	    msg_size = sizeof(hv_vmbus_channel_msg_info)
353		+ sizeof(hv_vmbus_channel_gpadl_header)
354		+ sizeof(hv_gpa_range)
355		+ pfnCount * sizeof(uint64_t);
356	    msg_header = malloc(msg_size, M_DEVBUF, M_NOWAIT | M_ZERO);
357	    KASSERT(
358		msg_header != NULL,
359		("Error VMBUS: malloc failed to allocate Gpadl Message!"));
360	    if (msg_header == NULL)
361		return (ENOMEM);
362
363	    TAILQ_INIT(&msg_header->sub_msg_list_anchor);
364	    msg_header->message_size = msg_size;
365
366	    gpa_header = (hv_vmbus_channel_gpadl_header*) msg_header->msg;
367	    gpa_header->range_count = 1;
368	    gpa_header->range_buf_len = sizeof(hv_gpa_range)
369		+ page_count * sizeof(uint64_t);
370	    gpa_header->range[0].byte_offset = 0;
371	    gpa_header->range[0].byte_count = size;
372	    for (i = 0; i < pfnCount; i++) {
373		gpa_header->range[0].pfn_array[i] = pfn + i;
374	    }
375	    *msg_info = msg_header;
376	    *message_count = 1;
377
378	    pfnSum = pfnCount;
379	    pfnLeft = page_count - pfnCount;
380
381	    /*
382	     *  figure out how many pfns we can fit
383	     */
384	    pfnSize = HV_MAX_SIZE_CHANNEL_MESSAGE
385		- sizeof(hv_vmbus_channel_gpadl_body);
386	    pfnCount = pfnSize / sizeof(uint64_t);
387
388	    /*
389	     * fill in the body
390	     */
391	    while (pfnLeft) {
392		if (pfnLeft > pfnCount) {
393		    pfnCurr = pfnCount;
394		} else {
395		    pfnCurr = pfnLeft;
396		}
397
398		msg_size = sizeof(hv_vmbus_channel_msg_info) +
399		    sizeof(hv_vmbus_channel_gpadl_body) +
400		    pfnCurr * sizeof(uint64_t);
401		msg_body = malloc(msg_size, M_DEVBUF, M_NOWAIT | M_ZERO);
402		KASSERT(
403		    msg_body != NULL,
404		    ("Error VMBUS: malloc failed to allocate Gpadl msg_body!"));
405		if (msg_body == NULL)
406		    return (ENOMEM);
407
408		msg_body->message_size = msg_size;
409		(*message_count)++;
410		gpadl_body =
411		    (hv_vmbus_channel_gpadl_body*) msg_body->msg;
412		/*
413		 * gpadl_body->gpadl = kbuffer;
414		 */
415		for (i = 0; i < pfnCurr; i++) {
416		    gpadl_body->pfn[i] = pfn + pfnSum + i;
417		}
418
419		TAILQ_INSERT_TAIL(
420		    &msg_header->sub_msg_list_anchor,
421		    msg_body,
422		    msg_list_entry);
423		pfnSum += pfnCurr;
424		pfnLeft -= pfnCurr;
425	    }
426	} else { /* else everything fits in a header */
427
428	    msg_size = sizeof(hv_vmbus_channel_msg_info) +
429		sizeof(hv_vmbus_channel_gpadl_header) +
430		sizeof(hv_gpa_range) +
431		page_count * sizeof(uint64_t);
432	    msg_header = malloc(msg_size, M_DEVBUF, M_NOWAIT | M_ZERO);
433	    KASSERT(
434		msg_header != NULL,
435		("Error VMBUS: malloc failed to allocate Gpadl Message!"));
436	    if (msg_header == NULL)
437		return (ENOMEM);
438
439	    msg_header->message_size = msg_size;
440
441	    gpa_header = (hv_vmbus_channel_gpadl_header*) msg_header->msg;
442	    gpa_header->range_count = 1;
443	    gpa_header->range_buf_len = sizeof(hv_gpa_range) +
444		page_count * sizeof(uint64_t);
445	    gpa_header->range[0].byte_offset = 0;
446	    gpa_header->range[0].byte_count = size;
447	    for (i = 0; i < page_count; i++) {
448		gpa_header->range[0].pfn_array[i] = pfn + i;
449	    }
450
451	    *msg_info = msg_header;
452	    *message_count = 1;
453	}
454
455	return (0);
456}
457
458/**
459 * @brief Establish a GPADL for the specified buffer
460 */
461int
462hv_vmbus_channel_establish_gpadl(
463	hv_vmbus_channel*	channel,
464	void*			contig_buffer,
465	uint32_t		size, /* page-size multiple */
466	uint32_t*		gpadl_handle)
467
468{
469	int ret = 0;
470	hv_vmbus_channel_gpadl_header*	gpadl_msg;
471	hv_vmbus_channel_gpadl_body*	gpadl_body;
472	hv_vmbus_channel_msg_info*	msg_info;
473	hv_vmbus_channel_msg_info*	sub_msg_info;
474	uint32_t			msg_count;
475	hv_vmbus_channel_msg_info*	curr;
476	uint32_t			next_gpadl_handle;
477
478	next_gpadl_handle = atomic_fetchadd_int(
479	    &hv_vmbus_g_connection.next_gpadl_handle, 1);
480
481	ret = vmbus_channel_create_gpadl_header(
482		contig_buffer, size, &msg_info, &msg_count);
483
484	if(ret != 0) {
485		/*
486		 * XXX
487		 * We can _not_ even revert the above incremental,
488		 * if multiple GPADL establishments are running
489		 * parallelly, decrement the global next_gpadl_handle
490		 * is calling for _big_ trouble.  A better solution
491		 * is to have a 0-based GPADL id bitmap ...
492		 */
493		return ret;
494	}
495
496	sema_init(&msg_info->wait_sema, 0, "Open Info Sema");
497	gpadl_msg = (hv_vmbus_channel_gpadl_header*) msg_info->msg;
498	gpadl_msg->header.message_type = HV_CHANNEL_MESSAGEL_GPADL_HEADER;
499	gpadl_msg->child_rel_id = channel->offer_msg.child_rel_id;
500	gpadl_msg->gpadl = next_gpadl_handle;
501
502	mtx_lock(&hv_vmbus_g_connection.channel_msg_lock);
503	TAILQ_INSERT_TAIL(
504		&hv_vmbus_g_connection.channel_msg_anchor,
505		msg_info,
506		msg_list_entry);
507
508	mtx_unlock(&hv_vmbus_g_connection.channel_msg_lock);
509
510	ret = hv_vmbus_post_message(
511		gpadl_msg,
512		msg_info->message_size -
513		    (uint32_t) sizeof(hv_vmbus_channel_msg_info));
514
515	if (ret != 0)
516	    goto cleanup;
517
518	if (msg_count > 1) {
519	    TAILQ_FOREACH(curr,
520		    &msg_info->sub_msg_list_anchor, msg_list_entry) {
521		sub_msg_info = curr;
522		gpadl_body =
523		    (hv_vmbus_channel_gpadl_body*) sub_msg_info->msg;
524
525		gpadl_body->header.message_type =
526		    HV_CHANNEL_MESSAGE_GPADL_BODY;
527		gpadl_body->gpadl = next_gpadl_handle;
528
529		ret = hv_vmbus_post_message(
530			gpadl_body,
531			sub_msg_info->message_size
532			    - (uint32_t) sizeof(hv_vmbus_channel_msg_info));
533		 /* if (the post message failed) give up and clean up */
534		if(ret != 0)
535		    goto cleanup;
536	    }
537	}
538
539	ret = sema_timedwait(&msg_info->wait_sema, 5 * hz); /* KYS 5 seconds*/
540	if (ret != 0)
541	    goto cleanup;
542
543	*gpadl_handle = gpadl_msg->gpadl;
544
545cleanup:
546
547	mtx_lock(&hv_vmbus_g_connection.channel_msg_lock);
548	TAILQ_REMOVE(&hv_vmbus_g_connection.channel_msg_anchor,
549		msg_info, msg_list_entry);
550	mtx_unlock(&hv_vmbus_g_connection.channel_msg_lock);
551
552	sema_destroy(&msg_info->wait_sema);
553	free(msg_info, M_DEVBUF);
554
555	return (ret);
556}
557
558/**
559 * @brief Teardown the specified GPADL handle
560 */
561int
562hv_vmbus_channel_teardown_gpdal(
563	hv_vmbus_channel*	channel,
564	uint32_t		gpadl_handle)
565{
566	int					ret = 0;
567	hv_vmbus_channel_gpadl_teardown*	msg;
568	hv_vmbus_channel_msg_info*		info;
569
570	info = (hv_vmbus_channel_msg_info *)
571		malloc(	sizeof(hv_vmbus_channel_msg_info) +
572			sizeof(hv_vmbus_channel_gpadl_teardown),
573				M_DEVBUF, M_NOWAIT);
574	KASSERT(info != NULL,
575	    ("Error VMBUS: malloc failed to allocate Gpadl Teardown Msg!"));
576	if (info == NULL) {
577	    ret = ENOMEM;
578	    goto cleanup;
579	}
580
581	sema_init(&info->wait_sema, 0, "Open Info Sema");
582
583	msg = (hv_vmbus_channel_gpadl_teardown*) info->msg;
584
585	msg->header.message_type = HV_CHANNEL_MESSAGE_GPADL_TEARDOWN;
586	msg->child_rel_id = channel->offer_msg.child_rel_id;
587	msg->gpadl = gpadl_handle;
588
589	mtx_lock(&hv_vmbus_g_connection.channel_msg_lock);
590	TAILQ_INSERT_TAIL(&hv_vmbus_g_connection.channel_msg_anchor,
591			info, msg_list_entry);
592	mtx_unlock(&hv_vmbus_g_connection.channel_msg_lock);
593
594	ret = hv_vmbus_post_message(msg,
595			sizeof(hv_vmbus_channel_gpadl_teardown));
596	if (ret != 0)
597	    goto cleanup;
598
599	ret = sema_timedwait(&info->wait_sema, 5 * hz); /* KYS 5 seconds */
600
601cleanup:
602	/*
603	 * Received a torndown response
604	 */
605	mtx_lock(&hv_vmbus_g_connection.channel_msg_lock);
606	TAILQ_REMOVE(&hv_vmbus_g_connection.channel_msg_anchor,
607			info, msg_list_entry);
608	mtx_unlock(&hv_vmbus_g_connection.channel_msg_lock);
609	sema_destroy(&info->wait_sema);
610	free(info, M_DEVBUF);
611
612	return (ret);
613}
614
615static void
616hv_vmbus_channel_close_internal(hv_vmbus_channel *channel)
617{
618	int ret = 0;
619	struct taskqueue *rxq = channel->rxq;
620	hv_vmbus_channel_close_channel* msg;
621	hv_vmbus_channel_msg_info* info;
622
623	channel->state = HV_CHANNEL_OPEN_STATE;
624
625	/*
626	 * set rxq to NULL to avoid more requests be scheduled
627	 */
628	channel->rxq = NULL;
629	taskqueue_drain(rxq, &channel->channel_task);
630	channel->on_channel_callback = NULL;
631
632	/**
633	 * Send a closing message
634	 */
635	info = (hv_vmbus_channel_msg_info *)
636		malloc(	sizeof(hv_vmbus_channel_msg_info) +
637			sizeof(hv_vmbus_channel_close_channel),
638				M_DEVBUF, M_NOWAIT);
639	KASSERT(info != NULL, ("VMBUS: malloc failed hv_vmbus_channel_close!"));
640	if(info == NULL)
641	    return;
642
643	msg = (hv_vmbus_channel_close_channel*) info->msg;
644	msg->header.message_type = HV_CHANNEL_MESSAGE_CLOSE_CHANNEL;
645	msg->child_rel_id = channel->offer_msg.child_rel_id;
646
647	ret = hv_vmbus_post_message(
648		msg, sizeof(hv_vmbus_channel_close_channel));
649
650	/* Tear down the gpadl for the channel's ring buffer */
651	if (channel->ring_buffer_gpadl_handle) {
652		hv_vmbus_channel_teardown_gpdal(channel,
653			channel->ring_buffer_gpadl_handle);
654	}
655
656	/* TODO: Send a msg to release the childRelId */
657
658	/* cleanup the ring buffers for this channel */
659	hv_ring_buffer_cleanup(&channel->outbound);
660	hv_ring_buffer_cleanup(&channel->inbound);
661
662	contigfree(channel->ring_buffer_pages, channel->ring_buffer_size,
663	    M_DEVBUF);
664
665	free(info, M_DEVBUF);
666}
667
668/**
669 * @brief Close the specified channel
670 */
671void
672hv_vmbus_channel_close(hv_vmbus_channel *channel)
673{
674	hv_vmbus_channel*	sub_channel;
675
676	if (channel->primary_channel != NULL) {
677		/*
678		 * We only close multi-channels when the primary is
679		 * closed.
680		 */
681		return;
682	}
683
684	/*
685	 * Close all multi-channels first.
686	 */
687	TAILQ_FOREACH(sub_channel, &channel->sc_list_anchor,
688	    sc_list_entry) {
689		if (sub_channel->state != HV_CHANNEL_OPENED_STATE)
690			continue;
691		hv_vmbus_channel_close_internal(sub_channel);
692	}
693	/*
694	 * Then close the primary channel.
695	 */
696	hv_vmbus_channel_close_internal(channel);
697}
698
699/**
700 * @brief Send the specified buffer on the given channel
701 */
702int
703hv_vmbus_channel_send_packet(
704	hv_vmbus_channel*	channel,
705	void*			buffer,
706	uint32_t		buffer_len,
707	uint64_t		request_id,
708	hv_vmbus_packet_type	type,
709	uint32_t		flags)
710{
711	int			ret = 0;
712	hv_vm_packet_descriptor	desc;
713	uint32_t		packet_len;
714	uint64_t		aligned_data;
715	uint32_t		packet_len_aligned;
716	boolean_t		need_sig;
717	hv_vmbus_sg_buffer_list	buffer_list[3];
718
719	packet_len = sizeof(hv_vm_packet_descriptor) + buffer_len;
720	packet_len_aligned = HV_ALIGN_UP(packet_len, sizeof(uint64_t));
721	aligned_data = 0;
722
723	/* Setup the descriptor */
724	desc.type = type;   /* HV_VMBUS_PACKET_TYPE_DATA_IN_BAND;             */
725	desc.flags = flags; /* HV_VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED */
726			    /* in 8-bytes granularity */
727	desc.data_offset8 = sizeof(hv_vm_packet_descriptor) >> 3;
728	desc.length8 = (uint16_t) (packet_len_aligned >> 3);
729	desc.transaction_id = request_id;
730
731	buffer_list[0].data = &desc;
732	buffer_list[0].length = sizeof(hv_vm_packet_descriptor);
733
734	buffer_list[1].data = buffer;
735	buffer_list[1].length = buffer_len;
736
737	buffer_list[2].data = &aligned_data;
738	buffer_list[2].length = packet_len_aligned - packet_len;
739
740	ret = hv_ring_buffer_write(&channel->outbound, buffer_list, 3,
741	    &need_sig);
742
743	/* TODO: We should determine if this is optional */
744	if (ret == 0 && need_sig) {
745		vmbus_channel_set_event(channel);
746	}
747
748	return (ret);
749}
750
751/**
752 * @brief Send a range of single-page buffer packets using
753 * a GPADL Direct packet type
754 */
755int
756hv_vmbus_channel_send_packet_pagebuffer(
757	hv_vmbus_channel*	channel,
758	hv_vmbus_page_buffer	page_buffers[],
759	uint32_t		page_count,
760	void*			buffer,
761	uint32_t		buffer_len,
762	uint64_t		request_id)
763{
764
765	int					ret = 0;
766	boolean_t				need_sig;
767	uint32_t				packet_len;
768	uint32_t				page_buflen;
769	uint32_t				packetLen_aligned;
770	hv_vmbus_sg_buffer_list			buffer_list[4];
771	hv_vmbus_channel_packet_page_buffer	desc;
772	uint32_t				descSize;
773	uint64_t				alignedData = 0;
774
775	if (page_count > HV_MAX_PAGE_BUFFER_COUNT)
776		return (EINVAL);
777
778	/*
779	 * Adjust the size down since hv_vmbus_channel_packet_page_buffer
780	 *  is the largest size we support
781	 */
782	descSize = __offsetof(hv_vmbus_channel_packet_page_buffer, range);
783	page_buflen = sizeof(hv_vmbus_page_buffer) * page_count;
784	packet_len = descSize + page_buflen + buffer_len;
785	packetLen_aligned = HV_ALIGN_UP(packet_len, sizeof(uint64_t));
786
787	/* Setup the descriptor */
788	desc.type = HV_VMBUS_PACKET_TYPE_DATA_USING_GPA_DIRECT;
789	desc.flags = HV_VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
790	/* in 8-bytes granularity */
791	desc.data_offset8 = (descSize + page_buflen) >> 3;
792	desc.length8 = (uint16_t) (packetLen_aligned >> 3);
793	desc.transaction_id = request_id;
794	desc.range_count = page_count;
795
796	buffer_list[0].data = &desc;
797	buffer_list[0].length = descSize;
798
799	buffer_list[1].data = page_buffers;
800	buffer_list[1].length = page_buflen;
801
802	buffer_list[2].data = buffer;
803	buffer_list[2].length = buffer_len;
804
805	buffer_list[3].data = &alignedData;
806	buffer_list[3].length = packetLen_aligned - packet_len;
807
808	ret = hv_ring_buffer_write(&channel->outbound, buffer_list, 4,
809	    &need_sig);
810
811	/* TODO: We should determine if this is optional */
812	if (ret == 0 && need_sig) {
813		vmbus_channel_set_event(channel);
814	}
815
816	return (ret);
817}
818
819/**
820 * @brief Send a multi-page buffer packet using a GPADL Direct packet type
821 */
822int
823hv_vmbus_channel_send_packet_multipagebuffer(
824	hv_vmbus_channel*		channel,
825	hv_vmbus_multipage_buffer*	multi_page_buffer,
826	void*				buffer,
827	uint32_t			buffer_len,
828	uint64_t			request_id)
829{
830
831	int			ret = 0;
832	uint32_t		desc_size;
833	boolean_t		need_sig;
834	uint32_t		packet_len;
835	uint32_t		packet_len_aligned;
836	uint32_t		pfn_count;
837	uint64_t		aligned_data = 0;
838	hv_vmbus_sg_buffer_list	buffer_list[3];
839	hv_vmbus_channel_packet_multipage_buffer desc;
840
841	pfn_count =
842	    HV_NUM_PAGES_SPANNED(
843		    multi_page_buffer->offset,
844		    multi_page_buffer->length);
845
846	if ((pfn_count == 0) || (pfn_count > HV_MAX_MULTIPAGE_BUFFER_COUNT))
847	    return (EINVAL);
848	/*
849	 * Adjust the size down since hv_vmbus_channel_packet_multipage_buffer
850	 * is the largest size we support
851	 */
852	desc_size =
853	    sizeof(hv_vmbus_channel_packet_multipage_buffer) -
854		    ((HV_MAX_MULTIPAGE_BUFFER_COUNT - pfn_count) *
855			sizeof(uint64_t));
856	packet_len = desc_size + buffer_len;
857	packet_len_aligned = HV_ALIGN_UP(packet_len, sizeof(uint64_t));
858
859	/*
860	 * Setup the descriptor
861	 */
862	desc.type = HV_VMBUS_PACKET_TYPE_DATA_USING_GPA_DIRECT;
863	desc.flags = HV_VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
864	desc.data_offset8 = desc_size >> 3; /* in 8-bytes granularity */
865	desc.length8 = (uint16_t) (packet_len_aligned >> 3);
866	desc.transaction_id = request_id;
867	desc.range_count = 1;
868
869	desc.range.length = multi_page_buffer->length;
870	desc.range.offset = multi_page_buffer->offset;
871
872	memcpy(desc.range.pfn_array, multi_page_buffer->pfn_array,
873		pfn_count * sizeof(uint64_t));
874
875	buffer_list[0].data = &desc;
876	buffer_list[0].length = desc_size;
877
878	buffer_list[1].data = buffer;
879	buffer_list[1].length = buffer_len;
880
881	buffer_list[2].data = &aligned_data;
882	buffer_list[2].length = packet_len_aligned - packet_len;
883
884	ret = hv_ring_buffer_write(&channel->outbound, buffer_list, 3,
885	    &need_sig);
886
887	/* TODO: We should determine if this is optional */
888	if (ret == 0 && need_sig) {
889	    vmbus_channel_set_event(channel);
890	}
891
892	return (ret);
893}
894
895/**
896 * @brief Retrieve the user packet on the specified channel
897 */
898int
899hv_vmbus_channel_recv_packet(
900	hv_vmbus_channel*	channel,
901	void*			Buffer,
902	uint32_t		buffer_len,
903	uint32_t*		buffer_actual_len,
904	uint64_t*		request_id)
905{
906	int			ret;
907	uint32_t		user_len;
908	uint32_t		packet_len;
909	hv_vm_packet_descriptor	desc;
910
911	*buffer_actual_len = 0;
912	*request_id = 0;
913
914	ret = hv_ring_buffer_peek(&channel->inbound, &desc,
915		sizeof(hv_vm_packet_descriptor));
916	if (ret != 0)
917		return (0);
918
919	packet_len = desc.length8 << 3;
920	user_len = packet_len - (desc.data_offset8 << 3);
921
922	*buffer_actual_len = user_len;
923
924	if (user_len > buffer_len)
925		return (EINVAL);
926
927	*request_id = desc.transaction_id;
928
929	/* Copy over the packet to the user buffer */
930	ret = hv_ring_buffer_read(&channel->inbound, Buffer, user_len,
931		(desc.data_offset8 << 3));
932
933	return (0);
934}
935
936/**
937 * @brief Retrieve the raw packet on the specified channel
938 */
939int
940hv_vmbus_channel_recv_packet_raw(
941	hv_vmbus_channel*	channel,
942	void*			buffer,
943	uint32_t		buffer_len,
944	uint32_t*		buffer_actual_len,
945	uint64_t*		request_id)
946{
947	int		ret;
948	uint32_t	packetLen;
949	hv_vm_packet_descriptor	desc;
950
951	*buffer_actual_len = 0;
952	*request_id = 0;
953
954	ret = hv_ring_buffer_peek(
955		&channel->inbound, &desc,
956		sizeof(hv_vm_packet_descriptor));
957
958	if (ret != 0)
959	    return (0);
960
961	packetLen = desc.length8 << 3;
962	*buffer_actual_len = packetLen;
963
964	if (packetLen > buffer_len)
965	    return (ENOBUFS);
966
967	*request_id = desc.transaction_id;
968
969	/* Copy over the entire packet to the user buffer */
970	ret = hv_ring_buffer_read(&channel->inbound, buffer, packetLen, 0);
971
972	return (0);
973}
974
975
976/**
977 * Process a channel event notification
978 */
979static void
980VmbusProcessChannelEvent(void* context, int pending)
981{
982	void* arg;
983	uint32_t bytes_to_read;
984	hv_vmbus_channel* channel = (hv_vmbus_channel*)context;
985	boolean_t is_batched_reading;
986
987	/**
988	 * Find the channel based on this relid and invokes
989	 * the channel callback to process the event
990	 */
991
992	if (channel == NULL) {
993		return;
994	}
995	/**
996	 * To deal with the race condition where we might
997	 * receive a packet while the relevant driver is
998	 * being unloaded, dispatch the callback while
999	 * holding the channel lock. The unloading driver
1000	 * will acquire the same channel lock to set the
1001	 * callback to NULL. This closes the window.
1002	 */
1003
1004	if (channel->on_channel_callback != NULL) {
1005		arg = channel->channel_callback_context;
1006		is_batched_reading = channel->batched_reading;
1007		/*
1008		 * Optimize host to guest signaling by ensuring:
1009		 * 1. While reading the channel, we disable interrupts from
1010		 *    host.
1011		 * 2. Ensure that we process all posted messages from the host
1012		 *    before returning from this callback.
1013		 * 3. Once we return, enable signaling from the host. Once this
1014		 *    state is set we check to see if additional packets are
1015		 *    available to read. In this case we repeat the process.
1016		 */
1017		do {
1018			if (is_batched_reading)
1019				hv_ring_buffer_read_begin(&channel->inbound);
1020
1021			channel->on_channel_callback(arg);
1022
1023			if (is_batched_reading)
1024				bytes_to_read =
1025				    hv_ring_buffer_read_end(&channel->inbound);
1026			else
1027				bytes_to_read = 0;
1028		} while (is_batched_reading && (bytes_to_read != 0));
1029	}
1030}
1031