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20
21#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22
23#include <linux/kernel.h>
24#include <linux/sched.h>
25#include <linux/wait.h>
26#include <linux/mm.h>
27#include <linux/slab.h>
28#include <linux/module.h>
29#include <linux/hyperv.h>
30
31#include "hyperv_vmbus.h"
32
33#define NUM_PAGES_SPANNED(addr, len) \
34((PAGE_ALIGN(addr + len) >> PAGE_SHIFT) - (addr >> PAGE_SHIFT))
35
36
37
38
39
40static void vmbus_setevent(struct vmbus_channel *channel)
41{
42 struct hv_monitor_page *monitorpage;
43
44 if (channel->offermsg.monitor_allocated) {
45
46 sync_set_bit(channel->offermsg.child_relid & 31,
47 (unsigned long *) vmbus_connection.send_int_page +
48 (channel->offermsg.child_relid >> 5));
49
50 monitorpage = vmbus_connection.monitor_pages;
51 monitorpage++;
52
53 sync_set_bit(channel->monitor_bit,
54 (unsigned long *)&monitorpage->trigger_group
55 [channel->monitor_grp].pending);
56
57 } else {
58 vmbus_set_event(channel);
59 }
60}
61
62
63
64
65void vmbus_get_debug_info(struct vmbus_channel *channel,
66 struct vmbus_channel_debug_info *debuginfo)
67{
68 struct hv_monitor_page *monitorpage;
69 u8 monitor_group = (u8)channel->offermsg.monitorid / 32;
70 u8 monitor_offset = (u8)channel->offermsg.monitorid % 32;
71
72 debuginfo->relid = channel->offermsg.child_relid;
73 debuginfo->state = channel->state;
74 memcpy(&debuginfo->interfacetype,
75 &channel->offermsg.offer.if_type, sizeof(uuid_le));
76 memcpy(&debuginfo->interface_instance,
77 &channel->offermsg.offer.if_instance,
78 sizeof(uuid_le));
79
80 monitorpage = (struct hv_monitor_page *)vmbus_connection.monitor_pages;
81
82 debuginfo->monitorid = channel->offermsg.monitorid;
83
84 debuginfo->servermonitor_pending =
85 monitorpage->trigger_group[monitor_group].pending;
86 debuginfo->servermonitor_latency =
87 monitorpage->latency[monitor_group][monitor_offset];
88 debuginfo->servermonitor_connectionid =
89 monitorpage->parameter[monitor_group]
90 [monitor_offset].connectionid.u.id;
91
92 monitorpage++;
93
94 debuginfo->clientmonitor_pending =
95 monitorpage->trigger_group[monitor_group].pending;
96 debuginfo->clientmonitor_latency =
97 monitorpage->latency[monitor_group][monitor_offset];
98 debuginfo->clientmonitor_connectionid =
99 monitorpage->parameter[monitor_group]
100 [monitor_offset].connectionid.u.id;
101
102 hv_ringbuffer_get_debuginfo(&channel->inbound, &debuginfo->inbound);
103 hv_ringbuffer_get_debuginfo(&channel->outbound, &debuginfo->outbound);
104}
105
106
107
108
109int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size,
110 u32 recv_ringbuffer_size, void *userdata, u32 userdatalen,
111 void (*onchannelcallback)(void *context), void *context)
112{
113 struct vmbus_channel_open_channel *open_msg;
114 struct vmbus_channel_msginfo *open_info = NULL;
115 void *in, *out;
116 unsigned long flags;
117 int ret, t, err = 0;
118
119 spin_lock_irqsave(&newchannel->sc_lock, flags);
120 if (newchannel->state == CHANNEL_OPEN_STATE) {
121 newchannel->state = CHANNEL_OPENING_STATE;
122 } else {
123 spin_unlock_irqrestore(&newchannel->sc_lock, flags);
124 return -EINVAL;
125 }
126 spin_unlock_irqrestore(&newchannel->sc_lock, flags);
127
128 newchannel->onchannel_callback = onchannelcallback;
129 newchannel->channel_callback_context = context;
130
131
132 out = (void *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
133 get_order(send_ringbuffer_size + recv_ringbuffer_size));
134
135 if (!out)
136 return -ENOMEM;
137
138
139 in = (void *)((unsigned long)out + send_ringbuffer_size);
140
141 newchannel->ringbuffer_pages = out;
142 newchannel->ringbuffer_pagecount = (send_ringbuffer_size +
143 recv_ringbuffer_size) >> PAGE_SHIFT;
144
145 ret = hv_ringbuffer_init(
146 &newchannel->outbound, out, send_ringbuffer_size);
147
148 if (ret != 0) {
149 err = ret;
150 goto error0;
151 }
152
153 ret = hv_ringbuffer_init(
154 &newchannel->inbound, in, recv_ringbuffer_size);
155 if (ret != 0) {
156 err = ret;
157 goto error0;
158 }
159
160
161
162 newchannel->ringbuffer_gpadlhandle = 0;
163
164 ret = vmbus_establish_gpadl(newchannel,
165 newchannel->outbound.ring_buffer,
166 send_ringbuffer_size +
167 recv_ringbuffer_size,
168 &newchannel->ringbuffer_gpadlhandle);
169
170 if (ret != 0) {
171 err = ret;
172 goto error0;
173 }
174
175
176 open_info = kmalloc(sizeof(*open_info) +
177 sizeof(struct vmbus_channel_open_channel),
178 GFP_KERNEL);
179 if (!open_info) {
180 err = -ENOMEM;
181 goto error0;
182 }
183
184 init_completion(&open_info->waitevent);
185
186 open_msg = (struct vmbus_channel_open_channel *)open_info->msg;
187 open_msg->header.msgtype = CHANNELMSG_OPENCHANNEL;
188 open_msg->openid = newchannel->offermsg.child_relid;
189 open_msg->child_relid = newchannel->offermsg.child_relid;
190 open_msg->ringbuffer_gpadlhandle = newchannel->ringbuffer_gpadlhandle;
191 open_msg->downstream_ringbuffer_pageoffset = send_ringbuffer_size >>
192 PAGE_SHIFT;
193 open_msg->target_vp = newchannel->target_vp;
194
195 if (userdatalen > MAX_USER_DEFINED_BYTES) {
196 err = -EINVAL;
197 goto error0;
198 }
199
200 if (userdatalen)
201 memcpy(open_msg->userdata, userdata, userdatalen);
202
203 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
204 list_add_tail(&open_info->msglistentry,
205 &vmbus_connection.chn_msg_list);
206 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
207
208 ret = vmbus_post_msg(open_msg,
209 sizeof(struct vmbus_channel_open_channel));
210
211 if (ret != 0)
212 goto error1;
213
214 t = wait_for_completion_timeout(&open_info->waitevent, 5*HZ);
215 if (t == 0) {
216 err = -ETIMEDOUT;
217 goto error1;
218 }
219
220
221 if (open_info->response.open_result.status)
222 err = open_info->response.open_result.status;
223
224 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
225 list_del(&open_info->msglistentry);
226 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
227
228 if (err == 0)
229 newchannel->state = CHANNEL_OPENED_STATE;
230
231 kfree(open_info);
232 return err;
233
234error1:
235 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
236 list_del(&open_info->msglistentry);
237 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
238
239error0:
240 free_pages((unsigned long)out,
241 get_order(send_ringbuffer_size + recv_ringbuffer_size));
242 kfree(open_info);
243 return err;
244}
245EXPORT_SYMBOL_GPL(vmbus_open);
246
247
248
249
250static int create_gpadl_header(void *kbuffer, u32 size,
251 struct vmbus_channel_msginfo **msginfo,
252 u32 *messagecount)
253{
254 int i;
255 int pagecount;
256 unsigned long long pfn;
257 struct vmbus_channel_gpadl_header *gpadl_header;
258 struct vmbus_channel_gpadl_body *gpadl_body;
259 struct vmbus_channel_msginfo *msgheader;
260 struct vmbus_channel_msginfo *msgbody = NULL;
261 u32 msgsize;
262
263 int pfnsum, pfncount, pfnleft, pfncurr, pfnsize;
264
265 pagecount = size >> PAGE_SHIFT;
266 pfn = virt_to_phys(kbuffer) >> PAGE_SHIFT;
267
268
269 pfnsize = MAX_SIZE_CHANNEL_MESSAGE -
270 sizeof(struct vmbus_channel_gpadl_header) -
271 sizeof(struct gpa_range);
272 pfncount = pfnsize / sizeof(u64);
273
274 if (pagecount > pfncount) {
275
276
277 msgsize = sizeof(struct vmbus_channel_msginfo) +
278 sizeof(struct vmbus_channel_gpadl_header) +
279 sizeof(struct gpa_range) + pfncount * sizeof(u64);
280 msgheader = kzalloc(msgsize, GFP_KERNEL);
281 if (!msgheader)
282 goto nomem;
283
284 INIT_LIST_HEAD(&msgheader->submsglist);
285 msgheader->msgsize = msgsize;
286
287 gpadl_header = (struct vmbus_channel_gpadl_header *)
288 msgheader->msg;
289 gpadl_header->rangecount = 1;
290 gpadl_header->range_buflen = sizeof(struct gpa_range) +
291 pagecount * sizeof(u64);
292 gpadl_header->range[0].byte_offset = 0;
293 gpadl_header->range[0].byte_count = size;
294 for (i = 0; i < pfncount; i++)
295 gpadl_header->range[0].pfn_array[i] = pfn+i;
296 *msginfo = msgheader;
297 *messagecount = 1;
298
299 pfnsum = pfncount;
300 pfnleft = pagecount - pfncount;
301
302
303 pfnsize = MAX_SIZE_CHANNEL_MESSAGE -
304 sizeof(struct vmbus_channel_gpadl_body);
305 pfncount = pfnsize / sizeof(u64);
306
307
308 while (pfnleft) {
309 if (pfnleft > pfncount)
310 pfncurr = pfncount;
311 else
312 pfncurr = pfnleft;
313
314 msgsize = sizeof(struct vmbus_channel_msginfo) +
315 sizeof(struct vmbus_channel_gpadl_body) +
316 pfncurr * sizeof(u64);
317 msgbody = kzalloc(msgsize, GFP_KERNEL);
318
319 if (!msgbody) {
320 struct vmbus_channel_msginfo *pos = NULL;
321 struct vmbus_channel_msginfo *tmp = NULL;
322
323
324
325 list_for_each_entry_safe(pos, tmp,
326 &msgheader->submsglist,
327 msglistentry) {
328
329 list_del(&pos->msglistentry);
330 kfree(pos);
331 }
332
333 goto nomem;
334 }
335
336 msgbody->msgsize = msgsize;
337 (*messagecount)++;
338 gpadl_body =
339 (struct vmbus_channel_gpadl_body *)msgbody->msg;
340
341
342
343
344
345
346
347 for (i = 0; i < pfncurr; i++)
348 gpadl_body->pfn[i] = pfn + pfnsum + i;
349
350
351 list_add_tail(&msgbody->msglistentry,
352 &msgheader->submsglist);
353 pfnsum += pfncurr;
354 pfnleft -= pfncurr;
355 }
356 } else {
357
358 msgsize = sizeof(struct vmbus_channel_msginfo) +
359 sizeof(struct vmbus_channel_gpadl_header) +
360 sizeof(struct gpa_range) + pagecount * sizeof(u64);
361 msgheader = kzalloc(msgsize, GFP_KERNEL);
362 if (msgheader == NULL)
363 goto nomem;
364 msgheader->msgsize = msgsize;
365
366 gpadl_header = (struct vmbus_channel_gpadl_header *)
367 msgheader->msg;
368 gpadl_header->rangecount = 1;
369 gpadl_header->range_buflen = sizeof(struct gpa_range) +
370 pagecount * sizeof(u64);
371 gpadl_header->range[0].byte_offset = 0;
372 gpadl_header->range[0].byte_count = size;
373 for (i = 0; i < pagecount; i++)
374 gpadl_header->range[0].pfn_array[i] = pfn+i;
375
376 *msginfo = msgheader;
377 *messagecount = 1;
378 }
379
380 return 0;
381nomem:
382 kfree(msgheader);
383 kfree(msgbody);
384 return -ENOMEM;
385}
386
387
388
389
390
391
392
393
394
395int vmbus_establish_gpadl(struct vmbus_channel *channel, void *kbuffer,
396 u32 size, u32 *gpadl_handle)
397{
398 struct vmbus_channel_gpadl_header *gpadlmsg;
399 struct vmbus_channel_gpadl_body *gpadl_body;
400 struct vmbus_channel_msginfo *msginfo = NULL;
401 struct vmbus_channel_msginfo *submsginfo;
402 u32 msgcount;
403 struct list_head *curr;
404 u32 next_gpadl_handle;
405 unsigned long flags;
406 int ret = 0;
407 int t;
408
409 next_gpadl_handle = atomic_read(&vmbus_connection.next_gpadl_handle);
410 atomic_inc(&vmbus_connection.next_gpadl_handle);
411
412 ret = create_gpadl_header(kbuffer, size, &msginfo, &msgcount);
413 if (ret)
414 return ret;
415
416 init_completion(&msginfo->waitevent);
417
418 gpadlmsg = (struct vmbus_channel_gpadl_header *)msginfo->msg;
419 gpadlmsg->header.msgtype = CHANNELMSG_GPADL_HEADER;
420 gpadlmsg->child_relid = channel->offermsg.child_relid;
421 gpadlmsg->gpadl = next_gpadl_handle;
422
423
424 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
425 list_add_tail(&msginfo->msglistentry,
426 &vmbus_connection.chn_msg_list);
427
428 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
429
430 ret = vmbus_post_msg(gpadlmsg, msginfo->msgsize -
431 sizeof(*msginfo));
432 if (ret != 0)
433 goto cleanup;
434
435 if (msgcount > 1) {
436 list_for_each(curr, &msginfo->submsglist) {
437
438 submsginfo = (struct vmbus_channel_msginfo *)curr;
439 gpadl_body =
440 (struct vmbus_channel_gpadl_body *)submsginfo->msg;
441
442 gpadl_body->header.msgtype =
443 CHANNELMSG_GPADL_BODY;
444 gpadl_body->gpadl = next_gpadl_handle;
445
446 ret = vmbus_post_msg(gpadl_body,
447 submsginfo->msgsize -
448 sizeof(*submsginfo));
449 if (ret != 0)
450 goto cleanup;
451
452 }
453 }
454 t = wait_for_completion_timeout(&msginfo->waitevent, 5*HZ);
455 BUG_ON(t == 0);
456
457
458
459 *gpadl_handle = gpadlmsg->gpadl;
460
461cleanup:
462 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
463 list_del(&msginfo->msglistentry);
464 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
465
466 kfree(msginfo);
467 return ret;
468}
469EXPORT_SYMBOL_GPL(vmbus_establish_gpadl);
470
471
472
473
474int vmbus_teardown_gpadl(struct vmbus_channel *channel, u32 gpadl_handle)
475{
476 struct vmbus_channel_gpadl_teardown *msg;
477 struct vmbus_channel_msginfo *info;
478 unsigned long flags;
479 int ret, t;
480
481 info = kmalloc(sizeof(*info) +
482 sizeof(struct vmbus_channel_gpadl_teardown), GFP_KERNEL);
483 if (!info)
484 return -ENOMEM;
485
486 init_completion(&info->waitevent);
487
488 msg = (struct vmbus_channel_gpadl_teardown *)info->msg;
489
490 msg->header.msgtype = CHANNELMSG_GPADL_TEARDOWN;
491 msg->child_relid = channel->offermsg.child_relid;
492 msg->gpadl = gpadl_handle;
493
494 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
495 list_add_tail(&info->msglistentry,
496 &vmbus_connection.chn_msg_list);
497 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
498 ret = vmbus_post_msg(msg,
499 sizeof(struct vmbus_channel_gpadl_teardown));
500
501 BUG_ON(ret != 0);
502 t = wait_for_completion_timeout(&info->waitevent, 5*HZ);
503 BUG_ON(t == 0);
504
505
506 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
507 list_del(&info->msglistentry);
508 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
509
510 kfree(info);
511 return ret;
512}
513EXPORT_SYMBOL_GPL(vmbus_teardown_gpadl);
514
515static void vmbus_close_internal(struct vmbus_channel *channel)
516{
517 struct vmbus_channel_close_channel *msg;
518 int ret;
519 unsigned long flags;
520
521 channel->state = CHANNEL_OPEN_STATE;
522 channel->sc_creation_callback = NULL;
523
524 spin_lock_irqsave(&channel->inbound_lock, flags);
525 channel->onchannel_callback = NULL;
526 spin_unlock_irqrestore(&channel->inbound_lock, flags);
527
528
529
530 msg = &channel->close_msg.msg;
531
532 msg->header.msgtype = CHANNELMSG_CLOSECHANNEL;
533 msg->child_relid = channel->offermsg.child_relid;
534
535 ret = vmbus_post_msg(msg, sizeof(struct vmbus_channel_close_channel));
536
537 BUG_ON(ret != 0);
538
539 if (channel->ringbuffer_gpadlhandle)
540 vmbus_teardown_gpadl(channel,
541 channel->ringbuffer_gpadlhandle);
542
543
544 hv_ringbuffer_cleanup(&channel->outbound);
545 hv_ringbuffer_cleanup(&channel->inbound);
546
547 free_pages((unsigned long)channel->ringbuffer_pages,
548 get_order(channel->ringbuffer_pagecount * PAGE_SIZE));
549
550
551}
552
553
554
555
556void vmbus_close(struct vmbus_channel *channel)
557{
558 struct list_head *cur, *tmp;
559 struct vmbus_channel *cur_channel;
560
561 if (channel->primary_channel != NULL) {
562
563
564
565
566 return;
567 }
568
569
570
571
572 list_for_each_safe(cur, tmp, &channel->sc_list) {
573 cur_channel = list_entry(cur, struct vmbus_channel, sc_list);
574 if (cur_channel->state != CHANNEL_OPENED_STATE)
575 continue;
576 vmbus_close_internal(cur_channel);
577 }
578
579
580
581 vmbus_close_internal(channel);
582}
583EXPORT_SYMBOL_GPL(vmbus_close);
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596
597
598
599int vmbus_sendpacket(struct vmbus_channel *channel, const void *buffer,
600 u32 bufferlen, u64 requestid,
601 enum vmbus_packet_type type, u32 flags)
602{
603 struct vmpacket_descriptor desc;
604 u32 packetlen = sizeof(struct vmpacket_descriptor) + bufferlen;
605 u32 packetlen_aligned = ALIGN(packetlen, sizeof(u64));
606 struct scatterlist bufferlist[3];
607 u64 aligned_data = 0;
608 int ret;
609 bool signal = false;
610
611
612
613 desc.type = type;
614 desc.flags = flags;
615
616 desc.offset8 = sizeof(struct vmpacket_descriptor) >> 3;
617 desc.len8 = (u16)(packetlen_aligned >> 3);
618 desc.trans_id = requestid;
619
620 sg_init_table(bufferlist, 3);
621 sg_set_buf(&bufferlist[0], &desc, sizeof(struct vmpacket_descriptor));
622 sg_set_buf(&bufferlist[1], buffer, bufferlen);
623 sg_set_buf(&bufferlist[2], &aligned_data,
624 packetlen_aligned - packetlen);
625
626 ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
627
628 if (ret == 0 && signal)
629 vmbus_setevent(channel);
630
631 return ret;
632}
633EXPORT_SYMBOL(vmbus_sendpacket);
634
635
636
637
638
639int vmbus_sendpacket_pagebuffer(struct vmbus_channel *channel,
640 struct hv_page_buffer pagebuffers[],
641 u32 pagecount, void *buffer, u32 bufferlen,
642 u64 requestid)
643{
644 int ret;
645 int i;
646 struct vmbus_channel_packet_page_buffer desc;
647 u32 descsize;
648 u32 packetlen;
649 u32 packetlen_aligned;
650 struct scatterlist bufferlist[3];
651 u64 aligned_data = 0;
652 bool signal = false;
653
654 if (pagecount > MAX_PAGE_BUFFER_COUNT)
655 return -EINVAL;
656
657
658
659
660
661
662 descsize = sizeof(struct vmbus_channel_packet_page_buffer) -
663 ((MAX_PAGE_BUFFER_COUNT - pagecount) *
664 sizeof(struct hv_page_buffer));
665 packetlen = descsize + bufferlen;
666 packetlen_aligned = ALIGN(packetlen, sizeof(u64));
667
668
669 desc.type = VM_PKT_DATA_USING_GPA_DIRECT;
670 desc.flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
671 desc.dataoffset8 = descsize >> 3;
672 desc.length8 = (u16)(packetlen_aligned >> 3);
673 desc.transactionid = requestid;
674 desc.rangecount = pagecount;
675
676 for (i = 0; i < pagecount; i++) {
677 desc.range[i].len = pagebuffers[i].len;
678 desc.range[i].offset = pagebuffers[i].offset;
679 desc.range[i].pfn = pagebuffers[i].pfn;
680 }
681
682 sg_init_table(bufferlist, 3);
683 sg_set_buf(&bufferlist[0], &desc, descsize);
684 sg_set_buf(&bufferlist[1], buffer, bufferlen);
685 sg_set_buf(&bufferlist[2], &aligned_data,
686 packetlen_aligned - packetlen);
687
688 ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
689
690 if (ret == 0 && signal)
691 vmbus_setevent(channel);
692
693 return ret;
694}
695EXPORT_SYMBOL_GPL(vmbus_sendpacket_pagebuffer);
696
697
698
699
700
701int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel,
702 struct hv_multipage_buffer *multi_pagebuffer,
703 void *buffer, u32 bufferlen, u64 requestid)
704{
705 int ret;
706 struct vmbus_channel_packet_multipage_buffer desc;
707 u32 descsize;
708 u32 packetlen;
709 u32 packetlen_aligned;
710 struct scatterlist bufferlist[3];
711 u64 aligned_data = 0;
712 bool signal = false;
713 u32 pfncount = NUM_PAGES_SPANNED(multi_pagebuffer->offset,
714 multi_pagebuffer->len);
715
716
717 if ((pfncount < 0) || (pfncount > MAX_MULTIPAGE_BUFFER_COUNT))
718 return -EINVAL;
719
720
721
722
723
724 descsize = sizeof(struct vmbus_channel_packet_multipage_buffer) -
725 ((MAX_MULTIPAGE_BUFFER_COUNT - pfncount) *
726 sizeof(u64));
727 packetlen = descsize + bufferlen;
728 packetlen_aligned = ALIGN(packetlen, sizeof(u64));
729
730
731
732 desc.type = VM_PKT_DATA_USING_GPA_DIRECT;
733 desc.flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
734 desc.dataoffset8 = descsize >> 3;
735 desc.length8 = (u16)(packetlen_aligned >> 3);
736 desc.transactionid = requestid;
737 desc.rangecount = 1;
738
739 desc.range.len = multi_pagebuffer->len;
740 desc.range.offset = multi_pagebuffer->offset;
741
742 memcpy(desc.range.pfn_array, multi_pagebuffer->pfn_array,
743 pfncount * sizeof(u64));
744
745 sg_init_table(bufferlist, 3);
746 sg_set_buf(&bufferlist[0], &desc, descsize);
747 sg_set_buf(&bufferlist[1], buffer, bufferlen);
748 sg_set_buf(&bufferlist[2], &aligned_data,
749 packetlen_aligned - packetlen);
750
751 ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
752
753 if (ret == 0 && signal)
754 vmbus_setevent(channel);
755
756 return ret;
757}
758EXPORT_SYMBOL_GPL(vmbus_sendpacket_multipagebuffer);
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773int vmbus_recvpacket(struct vmbus_channel *channel, void *buffer,
774 u32 bufferlen, u32 *buffer_actual_len, u64 *requestid)
775{
776 struct vmpacket_descriptor desc;
777 u32 packetlen;
778 u32 userlen;
779 int ret;
780 bool signal = false;
781
782 *buffer_actual_len = 0;
783 *requestid = 0;
784
785
786 ret = hv_ringbuffer_peek(&channel->inbound, &desc,
787 sizeof(struct vmpacket_descriptor));
788 if (ret != 0)
789 return 0;
790
791 packetlen = desc.len8 << 3;
792 userlen = packetlen - (desc.offset8 << 3);
793
794 *buffer_actual_len = userlen;
795
796 if (userlen > bufferlen) {
797
798 pr_err("Buffer too small - got %d needs %d\n",
799 bufferlen, userlen);
800 return -ETOOSMALL;
801 }
802
803 *requestid = desc.trans_id;
804
805
806 ret = hv_ringbuffer_read(&channel->inbound, buffer, userlen,
807 (desc.offset8 << 3), &signal);
808
809 if (signal)
810 vmbus_setevent(channel);
811
812 return 0;
813}
814EXPORT_SYMBOL(vmbus_recvpacket);
815
816
817
818
819int vmbus_recvpacket_raw(struct vmbus_channel *channel, void *buffer,
820 u32 bufferlen, u32 *buffer_actual_len,
821 u64 *requestid)
822{
823 struct vmpacket_descriptor desc;
824 u32 packetlen;
825 int ret;
826 bool signal = false;
827
828 *buffer_actual_len = 0;
829 *requestid = 0;
830
831
832 ret = hv_ringbuffer_peek(&channel->inbound, &desc,
833 sizeof(struct vmpacket_descriptor));
834 if (ret != 0)
835 return 0;
836
837
838 packetlen = desc.len8 << 3;
839
840 *buffer_actual_len = packetlen;
841
842 if (packetlen > bufferlen) {
843 pr_err("Buffer too small - needed %d bytes but "
844 "got space for only %d bytes\n",
845 packetlen, bufferlen);
846 return -ENOBUFS;
847 }
848
849 *requestid = desc.trans_id;
850
851
852 ret = hv_ringbuffer_read(&channel->inbound, buffer, packetlen, 0,
853 &signal);
854
855 if (signal)
856 vmbus_setevent(channel);
857
858 return 0;
859}
860EXPORT_SYMBOL_GPL(vmbus_recvpacket_raw);
861