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[FreeBSD/stable/10.git] / sys / dev / hyperv / vmbus / hv_channel.c
1 /*-
2  * Copyright (c) 2009-2012 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("$FreeBSD$");
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 <machine/bus.h>
40 #include <vm/vm.h>
41 #include <vm/vm_param.h>
42 #include <vm/pmap.h>
43
44 #include "hv_vmbus_priv.h"
45
46 static int      vmbus_channel_create_gpadl_header(
47                         /* must be phys and virt contiguous*/
48                         void*                           contig_buffer,
49                         /* page-size multiple */
50                         uint32_t                        size,
51                         hv_vmbus_channel_msg_info**     msg_info,
52                         uint32_t*                       message_count);
53
54 static void     vmbus_channel_set_event(hv_vmbus_channel* channel);
55 static void     VmbusProcessChannelEvent(void* channel, int pending);
56
57 /**
58  *  @brief Trigger an event notification on the specified channel
59  */
60 static void
61 vmbus_channel_set_event(hv_vmbus_channel *channel)
62 {
63         hv_vmbus_monitor_page *monitor_page;
64
65         if (channel->offer_msg.monitor_allocated) {
66                 /* Each uint32_t represents 32 channels */
67                 synch_set_bit((channel->offer_msg.child_rel_id & 31),
68                         ((uint32_t *)hv_vmbus_g_connection.send_interrupt_page
69                                 + ((channel->offer_msg.child_rel_id >> 5))));
70
71                 monitor_page = (hv_vmbus_monitor_page *)
72                         hv_vmbus_g_connection.monitor_page_2;
73
74                 synch_set_bit(channel->monitor_bit,
75                         (uint32_t *)&monitor_page->
76                                 trigger_group[channel->monitor_group].u.pending);
77         } else {
78                 hv_vmbus_set_event(channel);
79         }
80
81 }
82
83 /**
84  * @brief Open the specified channel
85  */
86 int
87 hv_vmbus_channel_open(
88         hv_vmbus_channel*               new_channel,
89         uint32_t                        send_ring_buffer_size,
90         uint32_t                        recv_ring_buffer_size,
91         void*                           user_data,
92         uint32_t                        user_data_len,
93         hv_vmbus_pfn_channel_callback   pfn_on_channel_callback,
94         void*                           context)
95 {
96
97         int ret = 0;
98         void *in, *out;
99         hv_vmbus_channel_open_channel*  open_msg;
100         hv_vmbus_channel_msg_info*      open_info;
101
102         mtx_lock(&new_channel->sc_lock);
103         if (new_channel->state == HV_CHANNEL_OPEN_STATE) {
104             new_channel->state = HV_CHANNEL_OPENING_STATE;
105         } else {
106             mtx_unlock(&new_channel->sc_lock);
107             if(bootverbose)
108                 printf("VMBUS: Trying to open channel <%p> which in "
109                     "%d state.\n", new_channel, new_channel->state);
110             return (EINVAL);
111         }
112         mtx_unlock(&new_channel->sc_lock);
113
114         new_channel->on_channel_callback = pfn_on_channel_callback;
115         new_channel->channel_callback_context = context;
116
117         new_channel->rxq = hv_vmbus_g_context.hv_event_queue[new_channel->target_cpu];
118         TASK_INIT(&new_channel->channel_task, 0, VmbusProcessChannelEvent, new_channel);
119
120         /* Allocate the ring buffer */
121         out = contigmalloc((send_ring_buffer_size + recv_ring_buffer_size),
122             M_DEVBUF, M_ZERO, 0UL, BUS_SPACE_MAXADDR, PAGE_SIZE, 0);
123         KASSERT(out != NULL,
124             ("Error VMBUS: contigmalloc failed to allocate Ring Buffer!"));
125         if (out == NULL)
126                 return (ENOMEM);
127
128         in = ((uint8_t *) out + send_ring_buffer_size);
129
130         new_channel->ring_buffer_pages = out;
131         new_channel->ring_buffer_page_count = (send_ring_buffer_size +
132             recv_ring_buffer_size) >> PAGE_SHIFT;
133         new_channel->ring_buffer_size = send_ring_buffer_size +
134             recv_ring_buffer_size;
135
136         hv_vmbus_ring_buffer_init(
137                 &new_channel->outbound,
138                 out,
139                 send_ring_buffer_size);
140
141         hv_vmbus_ring_buffer_init(
142                 &new_channel->inbound,
143                 in,
144                 recv_ring_buffer_size);
145
146         /**
147          * Establish the gpadl for the ring buffer
148          */
149         new_channel->ring_buffer_gpadl_handle = 0;
150
151         ret = hv_vmbus_channel_establish_gpadl(new_channel,
152                 new_channel->outbound.ring_buffer,
153                 send_ring_buffer_size + recv_ring_buffer_size,
154                 &new_channel->ring_buffer_gpadl_handle);
155
156         /**
157          * Create and init the channel open message
158          */
159         open_info = (hv_vmbus_channel_msg_info*) malloc(
160                 sizeof(hv_vmbus_channel_msg_info) +
161                         sizeof(hv_vmbus_channel_open_channel),
162                 M_DEVBUF,
163                 M_NOWAIT);
164         KASSERT(open_info != NULL,
165             ("Error VMBUS: malloc failed to allocate Open Channel message!"));
166
167         if (open_info == NULL)
168                 return (ENOMEM);
169
170         sema_init(&open_info->wait_sema, 0, "Open Info Sema");
171
172         open_msg = (hv_vmbus_channel_open_channel*) open_info->msg;
173         open_msg->header.message_type = HV_CHANNEL_MESSAGE_OPEN_CHANNEL;
174         open_msg->open_id = new_channel->offer_msg.child_rel_id;
175         open_msg->child_rel_id = new_channel->offer_msg.child_rel_id;
176         open_msg->ring_buffer_gpadl_handle =
177                 new_channel->ring_buffer_gpadl_handle;
178         open_msg->downstream_ring_buffer_page_offset = send_ring_buffer_size
179                 >> PAGE_SHIFT;
180         open_msg->target_vcpu = new_channel->target_vcpu;
181
182         if (user_data_len)
183                 memcpy(open_msg->user_data, user_data, user_data_len);
184
185         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
186         TAILQ_INSERT_TAIL(
187                 &hv_vmbus_g_connection.channel_msg_anchor,
188                 open_info,
189                 msg_list_entry);
190         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
191
192         ret = hv_vmbus_post_message(
193                 open_msg, sizeof(hv_vmbus_channel_open_channel));
194
195         if (ret != 0)
196             goto cleanup;
197
198         ret = sema_timedwait(&open_info->wait_sema, 5 * hz); /* KYS 5 seconds */
199
200         if (ret) {
201             if(bootverbose)
202                 printf("VMBUS: channel <%p> open timeout.\n", new_channel);
203             goto cleanup;
204         }
205
206         if (open_info->response.open_result.status == 0) {
207             new_channel->state = HV_CHANNEL_OPENED_STATE;
208             if(bootverbose)
209                 printf("VMBUS: channel <%p> open success.\n", new_channel);
210         } else {
211             if(bootverbose)
212                 printf("Error VMBUS: channel <%p> open failed - %d!\n",
213                         new_channel, open_info->response.open_result.status);
214         }
215
216         cleanup:
217         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
218         TAILQ_REMOVE(
219                 &hv_vmbus_g_connection.channel_msg_anchor,
220                 open_info,
221                 msg_list_entry);
222         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
223         sema_destroy(&open_info->wait_sema);
224         free(open_info, M_DEVBUF);
225
226         return (ret);
227 }
228
229 /**
230  * @brief Create a gpadl for the specified buffer
231  */
232 static int
233 vmbus_channel_create_gpadl_header(
234         void*                           contig_buffer,
235         uint32_t                        size,   /* page-size multiple */
236         hv_vmbus_channel_msg_info**     msg_info,
237         uint32_t*                       message_count)
238 {
239         int                             i;
240         int                             page_count;
241         unsigned long long              pfn;
242         uint32_t                        msg_size;
243         hv_vmbus_channel_gpadl_header*  gpa_header;
244         hv_vmbus_channel_gpadl_body*    gpadl_body;
245         hv_vmbus_channel_msg_info*      msg_header;
246         hv_vmbus_channel_msg_info*      msg_body;
247
248         int pfnSum, pfnCount, pfnLeft, pfnCurr, pfnSize;
249
250         page_count = size >> PAGE_SHIFT;
251         pfn = hv_get_phys_addr(contig_buffer) >> PAGE_SHIFT;
252
253         /*do we need a gpadl body msg */
254         pfnSize = HV_MAX_SIZE_CHANNEL_MESSAGE
255             - sizeof(hv_vmbus_channel_gpadl_header)
256             - sizeof(hv_gpa_range);
257         pfnCount = pfnSize / sizeof(uint64_t);
258
259         if (page_count > pfnCount) { /* if(we need a gpadl body)        */
260             /* fill in the header               */
261             msg_size = sizeof(hv_vmbus_channel_msg_info)
262                 + sizeof(hv_vmbus_channel_gpadl_header)
263                 + sizeof(hv_gpa_range)
264                 + pfnCount * sizeof(uint64_t);
265             msg_header = malloc(msg_size, M_DEVBUF, M_NOWAIT | M_ZERO);
266             KASSERT(
267                 msg_header != NULL,
268                 ("Error VMBUS: malloc failed to allocate Gpadl Message!"));
269             if (msg_header == NULL)
270                 return (ENOMEM);
271
272             TAILQ_INIT(&msg_header->sub_msg_list_anchor);
273             msg_header->message_size = msg_size;
274
275             gpa_header = (hv_vmbus_channel_gpadl_header*) msg_header->msg;
276             gpa_header->range_count = 1;
277             gpa_header->range_buf_len = sizeof(hv_gpa_range)
278                 + page_count * sizeof(uint64_t);
279             gpa_header->range[0].byte_offset = 0;
280             gpa_header->range[0].byte_count = size;
281             for (i = 0; i < pfnCount; i++) {
282                 gpa_header->range[0].pfn_array[i] = pfn + i;
283             }
284             *msg_info = msg_header;
285             *message_count = 1;
286
287             pfnSum = pfnCount;
288             pfnLeft = page_count - pfnCount;
289
290             /*
291              *  figure out how many pfns we can fit
292              */
293             pfnSize = HV_MAX_SIZE_CHANNEL_MESSAGE
294                 - sizeof(hv_vmbus_channel_gpadl_body);
295             pfnCount = pfnSize / sizeof(uint64_t);
296
297             /*
298              * fill in the body
299              */
300             while (pfnLeft) {
301                 if (pfnLeft > pfnCount) {
302                     pfnCurr = pfnCount;
303                 } else {
304                     pfnCurr = pfnLeft;
305                 }
306
307                 msg_size = sizeof(hv_vmbus_channel_msg_info) +
308                     sizeof(hv_vmbus_channel_gpadl_body) +
309                     pfnCurr * sizeof(uint64_t);
310                 msg_body = malloc(msg_size, M_DEVBUF, M_NOWAIT | M_ZERO);
311                 KASSERT(
312                     msg_body != NULL,
313                     ("Error VMBUS: malloc failed to allocate Gpadl msg_body!"));
314                 if (msg_body == NULL)
315                     return (ENOMEM);
316
317                 msg_body->message_size = msg_size;
318                 (*message_count)++;
319                 gpadl_body =
320                     (hv_vmbus_channel_gpadl_body*) msg_body->msg;
321                 /*
322                  * gpadl_body->gpadl = kbuffer;
323                  */
324                 for (i = 0; i < pfnCurr; i++) {
325                     gpadl_body->pfn[i] = pfn + pfnSum + i;
326                 }
327
328                 TAILQ_INSERT_TAIL(
329                     &msg_header->sub_msg_list_anchor,
330                     msg_body,
331                     msg_list_entry);
332                 pfnSum += pfnCurr;
333                 pfnLeft -= pfnCurr;
334             }
335         } else { /* else everything fits in a header */
336
337             msg_size = sizeof(hv_vmbus_channel_msg_info) +
338                 sizeof(hv_vmbus_channel_gpadl_header) +
339                 sizeof(hv_gpa_range) +
340                 page_count * sizeof(uint64_t);
341             msg_header = malloc(msg_size, M_DEVBUF, M_NOWAIT | M_ZERO);
342             KASSERT(
343                 msg_header != NULL,
344                 ("Error VMBUS: malloc failed to allocate Gpadl Message!"));
345             if (msg_header == NULL)
346                 return (ENOMEM);
347
348             msg_header->message_size = msg_size;
349
350             gpa_header = (hv_vmbus_channel_gpadl_header*) msg_header->msg;
351             gpa_header->range_count = 1;
352             gpa_header->range_buf_len = sizeof(hv_gpa_range) +
353                 page_count * sizeof(uint64_t);
354             gpa_header->range[0].byte_offset = 0;
355             gpa_header->range[0].byte_count = size;
356             for (i = 0; i < page_count; i++) {
357                 gpa_header->range[0].pfn_array[i] = pfn + i;
358             }
359
360             *msg_info = msg_header;
361             *message_count = 1;
362         }
363
364         return (0);
365 }
366
367 /**
368  * @brief Establish a GPADL for the specified buffer
369  */
370 int
371 hv_vmbus_channel_establish_gpadl(
372         hv_vmbus_channel*       channel,
373         void*                   contig_buffer,
374         uint32_t                size, /* page-size multiple */
375         uint32_t*               gpadl_handle)
376
377 {
378         int ret = 0;
379         hv_vmbus_channel_gpadl_header*  gpadl_msg;
380         hv_vmbus_channel_gpadl_body*    gpadl_body;
381         hv_vmbus_channel_msg_info*      msg_info;
382         hv_vmbus_channel_msg_info*      sub_msg_info;
383         uint32_t                        msg_count;
384         hv_vmbus_channel_msg_info*      curr;
385         uint32_t                        next_gpadl_handle;
386
387         next_gpadl_handle = hv_vmbus_g_connection.next_gpadl_handle;
388         atomic_add_int((int*) &hv_vmbus_g_connection.next_gpadl_handle, 1);
389
390         ret = vmbus_channel_create_gpadl_header(
391                 contig_buffer, size, &msg_info, &msg_count);
392
393         if(ret != 0) { /* if(allocation failed) return immediately */
394             /* reverse atomic_add_int above */
395             atomic_subtract_int((int*)
396                     &hv_vmbus_g_connection.next_gpadl_handle, 1);
397             return ret;
398         }
399
400         sema_init(&msg_info->wait_sema, 0, "Open Info Sema");
401         gpadl_msg = (hv_vmbus_channel_gpadl_header*) msg_info->msg;
402         gpadl_msg->header.message_type = HV_CHANNEL_MESSAGEL_GPADL_HEADER;
403         gpadl_msg->child_rel_id = channel->offer_msg.child_rel_id;
404         gpadl_msg->gpadl = next_gpadl_handle;
405
406         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
407         TAILQ_INSERT_TAIL(
408                 &hv_vmbus_g_connection.channel_msg_anchor,
409                 msg_info,
410                 msg_list_entry);
411
412         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
413
414         ret = hv_vmbus_post_message(
415                 gpadl_msg,
416                 msg_info->message_size -
417                     (uint32_t) sizeof(hv_vmbus_channel_msg_info));
418
419         if (ret != 0)
420             goto cleanup;
421
422         if (msg_count > 1) {
423             TAILQ_FOREACH(curr,
424                     &msg_info->sub_msg_list_anchor, msg_list_entry) {
425                 sub_msg_info = curr;
426                 gpadl_body =
427                     (hv_vmbus_channel_gpadl_body*) sub_msg_info->msg;
428
429                 gpadl_body->header.message_type =
430                     HV_CHANNEL_MESSAGE_GPADL_BODY;
431                 gpadl_body->gpadl = next_gpadl_handle;
432
433                 ret = hv_vmbus_post_message(
434                         gpadl_body,
435                         sub_msg_info->message_size
436                             - (uint32_t) sizeof(hv_vmbus_channel_msg_info));
437                  /* if (the post message failed) give up and clean up */
438                 if(ret != 0)
439                     goto cleanup;
440             }
441         }
442
443         ret = sema_timedwait(&msg_info->wait_sema, 5 * hz); /* KYS 5 seconds*/
444         if (ret != 0)
445             goto cleanup;
446
447         *gpadl_handle = gpadl_msg->gpadl;
448
449 cleanup:
450
451         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
452         TAILQ_REMOVE(&hv_vmbus_g_connection.channel_msg_anchor,
453                 msg_info, msg_list_entry);
454         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
455
456         sema_destroy(&msg_info->wait_sema);
457         free(msg_info, M_DEVBUF);
458
459         return (ret);
460 }
461
462 /**
463  * @brief Teardown the specified GPADL handle
464  */
465 int
466 hv_vmbus_channel_teardown_gpdal(
467         hv_vmbus_channel*       channel,
468         uint32_t                gpadl_handle)
469 {
470         int                                     ret = 0;
471         hv_vmbus_channel_gpadl_teardown*        msg;
472         hv_vmbus_channel_msg_info*              info;
473
474         info = (hv_vmbus_channel_msg_info *)
475                 malloc( sizeof(hv_vmbus_channel_msg_info) +
476                         sizeof(hv_vmbus_channel_gpadl_teardown),
477                                 M_DEVBUF, M_NOWAIT);
478         KASSERT(info != NULL,
479             ("Error VMBUS: malloc failed to allocate Gpadl Teardown Msg!"));
480         if (info == NULL) {
481             ret = ENOMEM;
482             goto cleanup;
483         }
484
485         sema_init(&info->wait_sema, 0, "Open Info Sema");
486
487         msg = (hv_vmbus_channel_gpadl_teardown*) info->msg;
488
489         msg->header.message_type = HV_CHANNEL_MESSAGE_GPADL_TEARDOWN;
490         msg->child_rel_id = channel->offer_msg.child_rel_id;
491         msg->gpadl = gpadl_handle;
492
493         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
494         TAILQ_INSERT_TAIL(&hv_vmbus_g_connection.channel_msg_anchor,
495                         info, msg_list_entry);
496         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
497
498         ret = hv_vmbus_post_message(msg,
499                         sizeof(hv_vmbus_channel_gpadl_teardown));
500         if (ret != 0) 
501             goto cleanup;
502         
503         ret = sema_timedwait(&info->wait_sema, 5 * hz); /* KYS 5 seconds */
504
505 cleanup:
506         /*
507          * Received a torndown response
508          */
509         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
510         TAILQ_REMOVE(&hv_vmbus_g_connection.channel_msg_anchor,
511                         info, msg_list_entry);
512         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
513         sema_destroy(&info->wait_sema);
514         free(info, M_DEVBUF);
515
516         return (ret);
517 }
518
519 static void
520 hv_vmbus_channel_close_internal(hv_vmbus_channel *channel)
521 {
522         int ret = 0;
523         struct taskqueue *rxq = channel->rxq;
524         hv_vmbus_channel_close_channel* msg;
525         hv_vmbus_channel_msg_info* info;
526
527         channel->state = HV_CHANNEL_OPEN_STATE;
528         channel->sc_creation_callback = NULL;
529
530         /*
531          * set rxq to NULL to avoid more requests be scheduled
532          */
533         channel->rxq = NULL;
534         taskqueue_drain(rxq, &channel->channel_task);
535         /*
536          * Grab the lock to prevent race condition when a packet received
537          * and unloading driver is in the process.
538          */
539         mtx_lock(&channel->inbound_lock);
540         channel->on_channel_callback = NULL;
541         mtx_unlock(&channel->inbound_lock);
542
543         /**
544          * Send a closing message
545          */
546         info = (hv_vmbus_channel_msg_info *)
547                 malloc( sizeof(hv_vmbus_channel_msg_info) +
548                         sizeof(hv_vmbus_channel_close_channel),
549                                 M_DEVBUF, M_NOWAIT);
550         KASSERT(info != NULL, ("VMBUS: malloc failed hv_vmbus_channel_close!"));
551         if(info == NULL)
552             return;
553
554         msg = (hv_vmbus_channel_close_channel*) info->msg;
555         msg->header.message_type = HV_CHANNEL_MESSAGE_CLOSE_CHANNEL;
556         msg->child_rel_id = channel->offer_msg.child_rel_id;
557
558         ret = hv_vmbus_post_message(
559                 msg, sizeof(hv_vmbus_channel_close_channel));
560
561         /* Tear down the gpadl for the channel's ring buffer */
562         if (channel->ring_buffer_gpadl_handle) {
563                 hv_vmbus_channel_teardown_gpdal(channel,
564                         channel->ring_buffer_gpadl_handle);
565         }
566
567         /* TODO: Send a msg to release the childRelId */
568
569         /* cleanup the ring buffers for this channel */
570         hv_ring_buffer_cleanup(&channel->outbound);
571         hv_ring_buffer_cleanup(&channel->inbound);
572
573         contigfree(channel->ring_buffer_pages, channel->ring_buffer_size,
574             M_DEVBUF);
575
576         free(info, M_DEVBUF);
577 }
578
579 /**
580  * @brief Close the specified channel
581  */
582 void
583 hv_vmbus_channel_close(hv_vmbus_channel *channel)
584 {
585         hv_vmbus_channel*       sub_channel;
586
587         if (channel->primary_channel != NULL) {
588                 /*
589                  * We only close multi-channels when the primary is
590                  * closed.
591                  */
592                 return;
593         }
594
595         /*
596          * Close all multi-channels first.
597          */
598         TAILQ_FOREACH(sub_channel, &channel->sc_list_anchor,
599             sc_list_entry) {
600                 if (sub_channel->state != HV_CHANNEL_OPENED_STATE)
601                         continue;
602                 hv_vmbus_channel_close_internal(sub_channel);
603         }
604         /*
605          * Then close the primary channel.
606          */
607         hv_vmbus_channel_close_internal(channel);
608 }
609
610 /**
611  * @brief Send the specified buffer on the given channel
612  */
613 int
614 hv_vmbus_channel_send_packet(
615         hv_vmbus_channel*       channel,
616         void*                   buffer,
617         uint32_t                buffer_len,
618         uint64_t                request_id,
619         hv_vmbus_packet_type    type,
620         uint32_t                flags)
621 {
622         int                     ret = 0;
623         hv_vm_packet_descriptor desc;
624         uint32_t                packet_len;
625         uint64_t                aligned_data;
626         uint32_t                packet_len_aligned;
627         boolean_t               need_sig;
628         hv_vmbus_sg_buffer_list buffer_list[3];
629
630         packet_len = sizeof(hv_vm_packet_descriptor) + buffer_len;
631         packet_len_aligned = HV_ALIGN_UP(packet_len, sizeof(uint64_t));
632         aligned_data = 0;
633
634         /* Setup the descriptor */
635         desc.type = type;   /* HV_VMBUS_PACKET_TYPE_DATA_IN_BAND;             */
636         desc.flags = flags; /* HV_VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED */
637                             /* in 8-bytes granularity */
638         desc.data_offset8 = sizeof(hv_vm_packet_descriptor) >> 3;
639         desc.length8 = (uint16_t) (packet_len_aligned >> 3);
640         desc.transaction_id = request_id;
641
642         buffer_list[0].data = &desc;
643         buffer_list[0].length = sizeof(hv_vm_packet_descriptor);
644
645         buffer_list[1].data = buffer;
646         buffer_list[1].length = buffer_len;
647
648         buffer_list[2].data = &aligned_data;
649         buffer_list[2].length = packet_len_aligned - packet_len;
650
651         ret = hv_ring_buffer_write(&channel->outbound, buffer_list, 3,
652             &need_sig);
653
654         /* TODO: We should determine if this is optional */
655         if (ret == 0 && need_sig) {
656                 vmbus_channel_set_event(channel);
657         }
658
659         return (ret);
660 }
661
662 /**
663  * @brief Send a range of single-page buffer packets using
664  * a GPADL Direct packet type
665  */
666 int
667 hv_vmbus_channel_send_packet_pagebuffer(
668         hv_vmbus_channel*       channel,
669         hv_vmbus_page_buffer    page_buffers[],
670         uint32_t                page_count,
671         void*                   buffer,
672         uint32_t                buffer_len,
673         uint64_t                request_id)
674 {
675
676         int                                     ret = 0;
677         boolean_t                               need_sig;
678         uint32_t                                packet_len;
679         uint32_t                                page_buflen;
680         uint32_t                                packetLen_aligned;
681         hv_vmbus_sg_buffer_list                 buffer_list[4];
682         hv_vmbus_channel_packet_page_buffer     desc;
683         uint32_t                                descSize;
684         uint64_t                                alignedData = 0;
685
686         if (page_count > HV_MAX_PAGE_BUFFER_COUNT)
687                 return (EINVAL);
688
689         /*
690          * Adjust the size down since hv_vmbus_channel_packet_page_buffer
691          *  is the largest size we support
692          */
693         descSize = __offsetof(hv_vmbus_channel_packet_page_buffer, range);
694         page_buflen = sizeof(hv_vmbus_page_buffer) * page_count;
695         packet_len = descSize + page_buflen + buffer_len;
696         packetLen_aligned = HV_ALIGN_UP(packet_len, sizeof(uint64_t));
697
698         /* Setup the descriptor */
699         desc.type = HV_VMBUS_PACKET_TYPE_DATA_USING_GPA_DIRECT;
700         desc.flags = HV_VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
701         /* in 8-bytes granularity */
702         desc.data_offset8 = (descSize + page_buflen) >> 3;
703         desc.length8 = (uint16_t) (packetLen_aligned >> 3);
704         desc.transaction_id = request_id;
705         desc.range_count = page_count;
706
707         buffer_list[0].data = &desc;
708         buffer_list[0].length = descSize;
709
710         buffer_list[1].data = page_buffers;
711         buffer_list[1].length = page_buflen;
712
713         buffer_list[2].data = buffer;
714         buffer_list[2].length = buffer_len;
715
716         buffer_list[3].data = &alignedData;
717         buffer_list[3].length = packetLen_aligned - packet_len;
718
719         ret = hv_ring_buffer_write(&channel->outbound, buffer_list, 4,
720             &need_sig);
721
722         /* TODO: We should determine if this is optional */
723         if (ret == 0 && need_sig) {
724                 vmbus_channel_set_event(channel);
725         }
726
727         return (ret);
728 }
729
730 /**
731  * @brief Send a multi-page buffer packet using a GPADL Direct packet type
732  */
733 int
734 hv_vmbus_channel_send_packet_multipagebuffer(
735         hv_vmbus_channel*               channel,
736         hv_vmbus_multipage_buffer*      multi_page_buffer,
737         void*                           buffer,
738         uint32_t                        buffer_len,
739         uint64_t                        request_id)
740 {
741
742         int                     ret = 0;
743         uint32_t                desc_size;
744         boolean_t               need_sig;
745         uint32_t                packet_len;
746         uint32_t                packet_len_aligned;
747         uint32_t                pfn_count;
748         uint64_t                aligned_data = 0;
749         hv_vmbus_sg_buffer_list buffer_list[3];
750         hv_vmbus_channel_packet_multipage_buffer desc;
751
752         pfn_count =
753             HV_NUM_PAGES_SPANNED(
754                     multi_page_buffer->offset,
755                     multi_page_buffer->length);
756
757         if ((pfn_count == 0) || (pfn_count > HV_MAX_MULTIPAGE_BUFFER_COUNT))
758             return (EINVAL);
759         /*
760          * Adjust the size down since hv_vmbus_channel_packet_multipage_buffer
761          * is the largest size we support
762          */
763         desc_size =
764             sizeof(hv_vmbus_channel_packet_multipage_buffer) -
765                     ((HV_MAX_MULTIPAGE_BUFFER_COUNT - pfn_count) *
766                         sizeof(uint64_t));
767         packet_len = desc_size + buffer_len;
768         packet_len_aligned = HV_ALIGN_UP(packet_len, sizeof(uint64_t));
769
770         /*
771          * Setup the descriptor
772          */
773         desc.type = HV_VMBUS_PACKET_TYPE_DATA_USING_GPA_DIRECT;
774         desc.flags = HV_VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
775         desc.data_offset8 = desc_size >> 3; /* in 8-bytes granularity */
776         desc.length8 = (uint16_t) (packet_len_aligned >> 3);
777         desc.transaction_id = request_id;
778         desc.range_count = 1;
779
780         desc.range.length = multi_page_buffer->length;
781         desc.range.offset = multi_page_buffer->offset;
782
783         memcpy(desc.range.pfn_array, multi_page_buffer->pfn_array,
784                 pfn_count * sizeof(uint64_t));
785
786         buffer_list[0].data = &desc;
787         buffer_list[0].length = desc_size;
788
789         buffer_list[1].data = buffer;
790         buffer_list[1].length = buffer_len;
791
792         buffer_list[2].data = &aligned_data;
793         buffer_list[2].length = packet_len_aligned - packet_len;
794
795         ret = hv_ring_buffer_write(&channel->outbound, buffer_list, 3,
796             &need_sig);
797
798         /* TODO: We should determine if this is optional */
799         if (ret == 0 && need_sig) {
800             vmbus_channel_set_event(channel);
801         }
802
803         return (ret);
804 }
805
806 /**
807  * @brief Retrieve the user packet on the specified channel
808  */
809 int
810 hv_vmbus_channel_recv_packet(
811         hv_vmbus_channel*       channel,
812         void*                   Buffer,
813         uint32_t                buffer_len,
814         uint32_t*               buffer_actual_len,
815         uint64_t*               request_id)
816 {
817         int                     ret;
818         uint32_t                user_len;
819         uint32_t                packet_len;
820         hv_vm_packet_descriptor desc;
821
822         *buffer_actual_len = 0;
823         *request_id = 0;
824
825         ret = hv_ring_buffer_peek(&channel->inbound, &desc,
826                 sizeof(hv_vm_packet_descriptor));
827         if (ret != 0)
828                 return (0);
829
830         packet_len = desc.length8 << 3;
831         user_len = packet_len - (desc.data_offset8 << 3);
832
833         *buffer_actual_len = user_len;
834
835         if (user_len > buffer_len)
836                 return (EINVAL);
837
838         *request_id = desc.transaction_id;
839
840         /* Copy over the packet to the user buffer */
841         ret = hv_ring_buffer_read(&channel->inbound, Buffer, user_len,
842                 (desc.data_offset8 << 3));
843
844         return (0);
845 }
846
847 /**
848  * @brief Retrieve the raw packet on the specified channel
849  */
850 int
851 hv_vmbus_channel_recv_packet_raw(
852         hv_vmbus_channel*       channel,
853         void*                   buffer,
854         uint32_t                buffer_len,
855         uint32_t*               buffer_actual_len,
856         uint64_t*               request_id)
857 {
858         int             ret;
859         uint32_t        packetLen;
860         uint32_t        userLen;
861         hv_vm_packet_descriptor desc;
862
863         *buffer_actual_len = 0;
864         *request_id = 0;
865
866         ret = hv_ring_buffer_peek(
867                 &channel->inbound, &desc,
868                 sizeof(hv_vm_packet_descriptor));
869
870         if (ret != 0)
871             return (0);
872
873         packetLen = desc.length8 << 3;
874         userLen = packetLen - (desc.data_offset8 << 3);
875
876         *buffer_actual_len = packetLen;
877
878         if (packetLen > buffer_len)
879             return (ENOBUFS);
880
881         *request_id = desc.transaction_id;
882
883         /* Copy over the entire packet to the user buffer */
884         ret = hv_ring_buffer_read(&channel->inbound, buffer, packetLen, 0);
885
886         return (0);
887 }
888
889
890 /**
891  * Process a channel event notification
892  */
893 static void
894 VmbusProcessChannelEvent(void* context, int pending)
895 {
896         void* arg;
897         uint32_t bytes_to_read;
898         hv_vmbus_channel* channel = (hv_vmbus_channel*)context;
899         boolean_t is_batched_reading;
900
901         /**
902          * Find the channel based on this relid and invokes
903          * the channel callback to process the event
904          */
905
906         if (channel == NULL) {
907                 return;
908         }
909         /**
910          * To deal with the race condition where we might
911          * receive a packet while the relevant driver is
912          * being unloaded, dispatch the callback while
913          * holding the channel lock. The unloading driver
914          * will acquire the same channel lock to set the
915          * callback to NULL. This closes the window.
916          */
917
918         /*
919          * Disable the lock due to newly added WITNESS check in r277723.
920          * Will seek other way to avoid race condition.
921          * -- whu
922          */
923         // mtx_lock(&channel->inbound_lock);
924         if (channel->on_channel_callback != NULL) {
925                 arg = channel->channel_callback_context;
926                 is_batched_reading = channel->batched_reading;
927                 /*
928                  * Optimize host to guest signaling by ensuring:
929                  * 1. While reading the channel, we disable interrupts from
930                  *    host.
931                  * 2. Ensure that we process all posted messages from the host
932                  *    before returning from this callback.
933                  * 3. Once we return, enable signaling from the host. Once this
934                  *    state is set we check to see if additional packets are
935                  *    available to read. In this case we repeat the process.
936                  */
937                 do {
938                         if (is_batched_reading)
939                                 hv_ring_buffer_read_begin(&channel->inbound);
940
941                         channel->on_channel_callback(arg);
942
943                         if (is_batched_reading)
944                                 bytes_to_read =
945                                     hv_ring_buffer_read_end(&channel->inbound);
946                         else
947                                 bytes_to_read = 0;
948                 } while (is_batched_reading && (bytes_to_read != 0));
949         }
950         // mtx_unlock(&channel->inbound_lock);
951 }