1 /*
2 * Copyright (c) 2009, Microsoft Corporation.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
11 * more details.
12 *
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
15 * Place - Suite 330, Boston, MA 02111-1307 USA.
16 *
17 * Authors:
18 * Haiyang Zhang <haiyangz@microsoft.com>
19 * Hank Janssen <hjanssen@microsoft.com>
20 */
21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22
23 #include <linux/kernel.h>
24 #include <linux/sched.h>
25 #include <linux/wait.h>
26 #include <linux/mm.h>
27 #include <linux/slab.h>
28 #include <linux/module.h>
29 #include <linux/hyperv.h>
30 #include <linux/uio.h>
31
32 #include "hyperv_vmbus.h"
33
34 #define NUM_PAGES_SPANNED(addr, len) \
35 ((PAGE_ALIGN(addr + len) >> PAGE_SHIFT) - (addr >> PAGE_SHIFT))
36
37 /*
38 * vmbus_setevent- Trigger an event notification on the specified
39 * channel.
40 */
vmbus_setevent(struct vmbus_channel * channel)41 static void vmbus_setevent(struct vmbus_channel *channel)
42 {
43 struct hv_monitor_page *monitorpage;
44
45 if (channel->offermsg.monitor_allocated) {
46 /* Each u32 represents 32 channels */
47 sync_set_bit(channel->offermsg.child_relid & 31,
48 (unsigned long *) vmbus_connection.send_int_page +
49 (channel->offermsg.child_relid >> 5));
50
51 /* Get the child to parent monitor page */
52 monitorpage = vmbus_connection.monitor_pages[1];
53
54 sync_set_bit(channel->monitor_bit,
55 (unsigned long *)&monitorpage->trigger_group
56 [channel->monitor_grp].pending);
57
58 } else {
59 vmbus_set_event(channel);
60 }
61 }
62
63 /*
64 * vmbus_open - Open the specified channel.
65 */
vmbus_open(struct vmbus_channel * newchannel,u32 send_ringbuffer_size,u32 recv_ringbuffer_size,void * userdata,u32 userdatalen,void (* onchannelcallback)(void * context),void * context)66 int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size,
67 u32 recv_ringbuffer_size, void *userdata, u32 userdatalen,
68 void (*onchannelcallback)(void *context), void *context)
69 {
70 struct vmbus_channel_open_channel *open_msg;
71 struct vmbus_channel_msginfo *open_info = NULL;
72 void *in, *out;
73 unsigned long flags;
74 int ret, t, err = 0;
75
76 spin_lock_irqsave(&newchannel->sc_lock, flags);
77 if (newchannel->state == CHANNEL_OPEN_STATE) {
78 newchannel->state = CHANNEL_OPENING_STATE;
79 } else {
80 spin_unlock_irqrestore(&newchannel->sc_lock, flags);
81 return -EINVAL;
82 }
83 spin_unlock_irqrestore(&newchannel->sc_lock, flags);
84
85 newchannel->onchannel_callback = onchannelcallback;
86 newchannel->channel_callback_context = context;
87
88 /* Allocate the ring buffer */
89 out = (void *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
90 get_order(send_ringbuffer_size + recv_ringbuffer_size));
91
92 if (!out)
93 return -ENOMEM;
94
95
96 in = (void *)((unsigned long)out + send_ringbuffer_size);
97
98 newchannel->ringbuffer_pages = out;
99 newchannel->ringbuffer_pagecount = (send_ringbuffer_size +
100 recv_ringbuffer_size) >> PAGE_SHIFT;
101
102 ret = hv_ringbuffer_init(
103 &newchannel->outbound, out, send_ringbuffer_size);
104
105 if (ret != 0) {
106 err = ret;
107 goto error0;
108 }
109
110 ret = hv_ringbuffer_init(
111 &newchannel->inbound, in, recv_ringbuffer_size);
112 if (ret != 0) {
113 err = ret;
114 goto error0;
115 }
116
117
118 /* Establish the gpadl for the ring buffer */
119 newchannel->ringbuffer_gpadlhandle = 0;
120
121 ret = vmbus_establish_gpadl(newchannel,
122 newchannel->outbound.ring_buffer,
123 send_ringbuffer_size +
124 recv_ringbuffer_size,
125 &newchannel->ringbuffer_gpadlhandle);
126
127 if (ret != 0) {
128 err = ret;
129 goto error0;
130 }
131
132 /* Create and init the channel open message */
133 open_info = kmalloc(sizeof(*open_info) +
134 sizeof(struct vmbus_channel_open_channel),
135 GFP_KERNEL);
136 if (!open_info) {
137 err = -ENOMEM;
138 goto error_gpadl;
139 }
140
141 init_completion(&open_info->waitevent);
142
143 open_msg = (struct vmbus_channel_open_channel *)open_info->msg;
144 open_msg->header.msgtype = CHANNELMSG_OPENCHANNEL;
145 open_msg->openid = newchannel->offermsg.child_relid;
146 open_msg->child_relid = newchannel->offermsg.child_relid;
147 open_msg->ringbuffer_gpadlhandle = newchannel->ringbuffer_gpadlhandle;
148 open_msg->downstream_ringbuffer_pageoffset = send_ringbuffer_size >>
149 PAGE_SHIFT;
150 open_msg->target_vp = newchannel->target_vp;
151
152 if (userdatalen > MAX_USER_DEFINED_BYTES) {
153 err = -EINVAL;
154 goto error_gpadl;
155 }
156
157 if (userdatalen)
158 memcpy(open_msg->userdata, userdata, userdatalen);
159
160 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
161 list_add_tail(&open_info->msglistentry,
162 &vmbus_connection.chn_msg_list);
163 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
164
165 ret = vmbus_post_msg(open_msg,
166 sizeof(struct vmbus_channel_open_channel));
167
168 if (ret != 0) {
169 err = ret;
170 goto error1;
171 }
172
173 t = wait_for_completion_timeout(&open_info->waitevent, 5*HZ);
174 if (t == 0) {
175 err = -ETIMEDOUT;
176 goto error1;
177 }
178
179
180 if (open_info->response.open_result.status)
181 err = open_info->response.open_result.status;
182
183 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
184 list_del(&open_info->msglistentry);
185 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
186
187 if (err == 0)
188 newchannel->state = CHANNEL_OPENED_STATE;
189
190 kfree(open_info);
191 return err;
192
193 error1:
194 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
195 list_del(&open_info->msglistentry);
196 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
197
198 error_gpadl:
199 vmbus_teardown_gpadl(newchannel, newchannel->ringbuffer_gpadlhandle);
200
201 error0:
202 free_pages((unsigned long)out,
203 get_order(send_ringbuffer_size + recv_ringbuffer_size));
204 kfree(open_info);
205 return err;
206 }
207 EXPORT_SYMBOL_GPL(vmbus_open);
208
209 /*
210 * create_gpadl_header - Creates a gpadl for the specified buffer
211 */
create_gpadl_header(void * kbuffer,u32 size,struct vmbus_channel_msginfo ** msginfo,u32 * messagecount)212 static int create_gpadl_header(void *kbuffer, u32 size,
213 struct vmbus_channel_msginfo **msginfo,
214 u32 *messagecount)
215 {
216 int i;
217 int pagecount;
218 struct vmbus_channel_gpadl_header *gpadl_header;
219 struct vmbus_channel_gpadl_body *gpadl_body;
220 struct vmbus_channel_msginfo *msgheader;
221 struct vmbus_channel_msginfo *msgbody = NULL;
222 u32 msgsize;
223
224 int pfnsum, pfncount, pfnleft, pfncurr, pfnsize;
225
226 pagecount = size >> PAGE_SHIFT;
227
228 /* do we need a gpadl body msg */
229 pfnsize = MAX_SIZE_CHANNEL_MESSAGE -
230 sizeof(struct vmbus_channel_gpadl_header) -
231 sizeof(struct gpa_range);
232 pfncount = pfnsize / sizeof(u64);
233
234 if (pagecount > pfncount) {
235 /* we need a gpadl body */
236 /* fill in the header */
237 msgsize = sizeof(struct vmbus_channel_msginfo) +
238 sizeof(struct vmbus_channel_gpadl_header) +
239 sizeof(struct gpa_range) + pfncount * sizeof(u64);
240 msgheader = kzalloc(msgsize, GFP_KERNEL);
241 if (!msgheader)
242 goto nomem;
243
244 INIT_LIST_HEAD(&msgheader->submsglist);
245 msgheader->msgsize = msgsize;
246
247 gpadl_header = (struct vmbus_channel_gpadl_header *)
248 msgheader->msg;
249 gpadl_header->rangecount = 1;
250 gpadl_header->range_buflen = sizeof(struct gpa_range) +
251 pagecount * sizeof(u64);
252 gpadl_header->range[0].byte_offset = 0;
253 gpadl_header->range[0].byte_count = size;
254 for (i = 0; i < pfncount; i++)
255 gpadl_header->range[0].pfn_array[i] = slow_virt_to_phys(
256 kbuffer + PAGE_SIZE * i) >> PAGE_SHIFT;
257 *msginfo = msgheader;
258 *messagecount = 1;
259
260 pfnsum = pfncount;
261 pfnleft = pagecount - pfncount;
262
263 /* how many pfns can we fit */
264 pfnsize = MAX_SIZE_CHANNEL_MESSAGE -
265 sizeof(struct vmbus_channel_gpadl_body);
266 pfncount = pfnsize / sizeof(u64);
267
268 /* fill in the body */
269 while (pfnleft) {
270 if (pfnleft > pfncount)
271 pfncurr = pfncount;
272 else
273 pfncurr = pfnleft;
274
275 msgsize = sizeof(struct vmbus_channel_msginfo) +
276 sizeof(struct vmbus_channel_gpadl_body) +
277 pfncurr * sizeof(u64);
278 msgbody = kzalloc(msgsize, GFP_KERNEL);
279
280 if (!msgbody) {
281 struct vmbus_channel_msginfo *pos = NULL;
282 struct vmbus_channel_msginfo *tmp = NULL;
283 /*
284 * Free up all the allocated messages.
285 */
286 list_for_each_entry_safe(pos, tmp,
287 &msgheader->submsglist,
288 msglistentry) {
289
290 list_del(&pos->msglistentry);
291 kfree(pos);
292 }
293
294 goto nomem;
295 }
296
297 msgbody->msgsize = msgsize;
298 (*messagecount)++;
299 gpadl_body =
300 (struct vmbus_channel_gpadl_body *)msgbody->msg;
301
302 /*
303 * Gpadl is u32 and we are using a pointer which could
304 * be 64-bit
305 * This is governed by the guest/host protocol and
306 * so the hypervisor gurantees that this is ok.
307 */
308 for (i = 0; i < pfncurr; i++)
309 gpadl_body->pfn[i] = slow_virt_to_phys(
310 kbuffer + PAGE_SIZE * (pfnsum + i)) >>
311 PAGE_SHIFT;
312
313 /* add to msg header */
314 list_add_tail(&msgbody->msglistentry,
315 &msgheader->submsglist);
316 pfnsum += pfncurr;
317 pfnleft -= pfncurr;
318 }
319 } else {
320 /* everything fits in a header */
321 msgsize = sizeof(struct vmbus_channel_msginfo) +
322 sizeof(struct vmbus_channel_gpadl_header) +
323 sizeof(struct gpa_range) + pagecount * sizeof(u64);
324 msgheader = kzalloc(msgsize, GFP_KERNEL);
325 if (msgheader == NULL)
326 goto nomem;
327 msgheader->msgsize = msgsize;
328
329 gpadl_header = (struct vmbus_channel_gpadl_header *)
330 msgheader->msg;
331 gpadl_header->rangecount = 1;
332 gpadl_header->range_buflen = sizeof(struct gpa_range) +
333 pagecount * sizeof(u64);
334 gpadl_header->range[0].byte_offset = 0;
335 gpadl_header->range[0].byte_count = size;
336 for (i = 0; i < pagecount; i++)
337 gpadl_header->range[0].pfn_array[i] = slow_virt_to_phys(
338 kbuffer + PAGE_SIZE * i) >> PAGE_SHIFT;
339
340 *msginfo = msgheader;
341 *messagecount = 1;
342 }
343
344 return 0;
345 nomem:
346 kfree(msgheader);
347 kfree(msgbody);
348 return -ENOMEM;
349 }
350
351 /*
352 * vmbus_establish_gpadl - Estabish a GPADL for the specified buffer
353 *
354 * @channel: a channel
355 * @kbuffer: from kmalloc or vmalloc
356 * @size: page-size multiple
357 * @gpadl_handle: some funky thing
358 */
vmbus_establish_gpadl(struct vmbus_channel * channel,void * kbuffer,u32 size,u32 * gpadl_handle)359 int vmbus_establish_gpadl(struct vmbus_channel *channel, void *kbuffer,
360 u32 size, u32 *gpadl_handle)
361 {
362 struct vmbus_channel_gpadl_header *gpadlmsg;
363 struct vmbus_channel_gpadl_body *gpadl_body;
364 struct vmbus_channel_msginfo *msginfo = NULL;
365 struct vmbus_channel_msginfo *submsginfo;
366 u32 msgcount;
367 struct list_head *curr;
368 u32 next_gpadl_handle;
369 unsigned long flags;
370 int ret = 0;
371
372 next_gpadl_handle = atomic_read(&vmbus_connection.next_gpadl_handle);
373 atomic_inc(&vmbus_connection.next_gpadl_handle);
374
375 ret = create_gpadl_header(kbuffer, size, &msginfo, &msgcount);
376 if (ret)
377 return ret;
378
379 init_completion(&msginfo->waitevent);
380
381 gpadlmsg = (struct vmbus_channel_gpadl_header *)msginfo->msg;
382 gpadlmsg->header.msgtype = CHANNELMSG_GPADL_HEADER;
383 gpadlmsg->child_relid = channel->offermsg.child_relid;
384 gpadlmsg->gpadl = next_gpadl_handle;
385
386
387 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
388 list_add_tail(&msginfo->msglistentry,
389 &vmbus_connection.chn_msg_list);
390
391 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
392
393 ret = vmbus_post_msg(gpadlmsg, msginfo->msgsize -
394 sizeof(*msginfo));
395 if (ret != 0)
396 goto cleanup;
397
398 if (msgcount > 1) {
399 list_for_each(curr, &msginfo->submsglist) {
400
401 submsginfo = (struct vmbus_channel_msginfo *)curr;
402 gpadl_body =
403 (struct vmbus_channel_gpadl_body *)submsginfo->msg;
404
405 gpadl_body->header.msgtype =
406 CHANNELMSG_GPADL_BODY;
407 gpadl_body->gpadl = next_gpadl_handle;
408
409 ret = vmbus_post_msg(gpadl_body,
410 submsginfo->msgsize -
411 sizeof(*submsginfo));
412 if (ret != 0)
413 goto cleanup;
414
415 }
416 }
417 wait_for_completion(&msginfo->waitevent);
418
419 /* At this point, we received the gpadl created msg */
420 *gpadl_handle = gpadlmsg->gpadl;
421
422 cleanup:
423 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
424 list_del(&msginfo->msglistentry);
425 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
426
427 kfree(msginfo);
428 return ret;
429 }
430 EXPORT_SYMBOL_GPL(vmbus_establish_gpadl);
431
432 /*
433 * vmbus_teardown_gpadl -Teardown the specified GPADL handle
434 */
vmbus_teardown_gpadl(struct vmbus_channel * channel,u32 gpadl_handle)435 int vmbus_teardown_gpadl(struct vmbus_channel *channel, u32 gpadl_handle)
436 {
437 struct vmbus_channel_gpadl_teardown *msg;
438 struct vmbus_channel_msginfo *info;
439 unsigned long flags;
440 int ret;
441
442 info = kmalloc(sizeof(*info) +
443 sizeof(struct vmbus_channel_gpadl_teardown), GFP_KERNEL);
444 if (!info)
445 return -ENOMEM;
446
447 init_completion(&info->waitevent);
448
449 msg = (struct vmbus_channel_gpadl_teardown *)info->msg;
450
451 msg->header.msgtype = CHANNELMSG_GPADL_TEARDOWN;
452 msg->child_relid = channel->offermsg.child_relid;
453 msg->gpadl = gpadl_handle;
454
455 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
456 list_add_tail(&info->msglistentry,
457 &vmbus_connection.chn_msg_list);
458 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
459 ret = vmbus_post_msg(msg,
460 sizeof(struct vmbus_channel_gpadl_teardown));
461
462 if (ret)
463 goto post_msg_err;
464
465 wait_for_completion(&info->waitevent);
466
467 post_msg_err:
468 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
469 list_del(&info->msglistentry);
470 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
471
472 kfree(info);
473 return ret;
474 }
475 EXPORT_SYMBOL_GPL(vmbus_teardown_gpadl);
476
reset_channel_cb(void * arg)477 static void reset_channel_cb(void *arg)
478 {
479 struct vmbus_channel *channel = arg;
480
481 channel->onchannel_callback = NULL;
482 }
483
vmbus_close_internal(struct vmbus_channel * channel)484 static int vmbus_close_internal(struct vmbus_channel *channel)
485 {
486 struct vmbus_channel_close_channel *msg;
487 int ret;
488
489 channel->state = CHANNEL_OPEN_STATE;
490 channel->sc_creation_callback = NULL;
491 /* Stop callback and cancel the timer asap */
492 if (channel->target_cpu != get_cpu()) {
493 put_cpu();
494 smp_call_function_single(channel->target_cpu, reset_channel_cb,
495 channel, true);
496 } else {
497 reset_channel_cb(channel);
498 put_cpu();
499 }
500
501 /* Send a closing message */
502
503 msg = &channel->close_msg.msg;
504
505 msg->header.msgtype = CHANNELMSG_CLOSECHANNEL;
506 msg->child_relid = channel->offermsg.child_relid;
507
508 ret = vmbus_post_msg(msg, sizeof(struct vmbus_channel_close_channel));
509
510 if (ret) {
511 pr_err("Close failed: close post msg return is %d\n", ret);
512 /*
513 * If we failed to post the close msg,
514 * it is perhaps better to leak memory.
515 */
516 return ret;
517 }
518
519 /* Tear down the gpadl for the channel's ring buffer */
520 if (channel->ringbuffer_gpadlhandle) {
521 ret = vmbus_teardown_gpadl(channel,
522 channel->ringbuffer_gpadlhandle);
523 if (ret) {
524 pr_err("Close failed: teardown gpadl return %d\n", ret);
525 /*
526 * If we failed to teardown gpadl,
527 * it is perhaps better to leak memory.
528 */
529 return ret;
530 }
531 }
532
533 /* Cleanup the ring buffers for this channel */
534 hv_ringbuffer_cleanup(&channel->outbound);
535 hv_ringbuffer_cleanup(&channel->inbound);
536
537 free_pages((unsigned long)channel->ringbuffer_pages,
538 get_order(channel->ringbuffer_pagecount * PAGE_SIZE));
539
540 return ret;
541 }
542
543 /*
544 * vmbus_close - Close the specified channel
545 */
vmbus_close(struct vmbus_channel * channel)546 void vmbus_close(struct vmbus_channel *channel)
547 {
548 struct list_head *cur, *tmp;
549 struct vmbus_channel *cur_channel;
550
551 if (channel->primary_channel != NULL) {
552 /*
553 * We will only close sub-channels when
554 * the primary is closed.
555 */
556 return;
557 }
558 /*
559 * Close all the sub-channels first and then close the
560 * primary channel.
561 */
562 list_for_each_safe(cur, tmp, &channel->sc_list) {
563 cur_channel = list_entry(cur, struct vmbus_channel, sc_list);
564 if (cur_channel->state != CHANNEL_OPENED_STATE)
565 continue;
566 vmbus_close_internal(cur_channel);
567 }
568 /*
569 * Now close the primary.
570 */
571 vmbus_close_internal(channel);
572 }
573 EXPORT_SYMBOL_GPL(vmbus_close);
574
575 /**
576 * vmbus_sendpacket() - Send the specified buffer on the given channel
577 * @channel: Pointer to vmbus_channel structure.
578 * @buffer: Pointer to the buffer you want to receive the data into.
579 * @bufferlen: Maximum size of what the the buffer will hold
580 * @requestid: Identifier of the request
581 * @type: Type of packet that is being send e.g. negotiate, time
582 * packet etc.
583 *
584 * Sends data in @buffer directly to hyper-v via the vmbus
585 * This will send the data unparsed to hyper-v.
586 *
587 * Mainly used by Hyper-V drivers.
588 */
vmbus_sendpacket(struct vmbus_channel * channel,void * buffer,u32 bufferlen,u64 requestid,enum vmbus_packet_type type,u32 flags)589 int vmbus_sendpacket(struct vmbus_channel *channel, void *buffer,
590 u32 bufferlen, u64 requestid,
591 enum vmbus_packet_type type, u32 flags)
592 {
593 struct vmpacket_descriptor desc;
594 u32 packetlen = sizeof(struct vmpacket_descriptor) + bufferlen;
595 u32 packetlen_aligned = ALIGN(packetlen, sizeof(u64));
596 struct kvec bufferlist[3];
597 u64 aligned_data = 0;
598 int ret;
599 bool signal = false;
600
601
602 /* Setup the descriptor */
603 desc.type = type; /* VmbusPacketTypeDataInBand; */
604 desc.flags = flags; /* VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED; */
605 /* in 8-bytes granularity */
606 desc.offset8 = sizeof(struct vmpacket_descriptor) >> 3;
607 desc.len8 = (u16)(packetlen_aligned >> 3);
608 desc.trans_id = requestid;
609
610 bufferlist[0].iov_base = &desc;
611 bufferlist[0].iov_len = sizeof(struct vmpacket_descriptor);
612 bufferlist[1].iov_base = buffer;
613 bufferlist[1].iov_len = bufferlen;
614 bufferlist[2].iov_base = &aligned_data;
615 bufferlist[2].iov_len = (packetlen_aligned - packetlen);
616
617 ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
618
619 if (ret == 0 && signal)
620 vmbus_setevent(channel);
621
622 return ret;
623 }
624 EXPORT_SYMBOL(vmbus_sendpacket);
625
626 /*
627 * vmbus_sendpacket_pagebuffer - Send a range of single-page buffer
628 * packets using a GPADL Direct packet type.
629 */
vmbus_sendpacket_pagebuffer(struct vmbus_channel * channel,struct hv_page_buffer pagebuffers[],u32 pagecount,void * buffer,u32 bufferlen,u64 requestid)630 int vmbus_sendpacket_pagebuffer(struct vmbus_channel *channel,
631 struct hv_page_buffer pagebuffers[],
632 u32 pagecount, void *buffer, u32 bufferlen,
633 u64 requestid)
634 {
635 int ret;
636 int i;
637 struct vmbus_channel_packet_page_buffer desc;
638 u32 descsize;
639 u32 packetlen;
640 u32 packetlen_aligned;
641 struct kvec bufferlist[3];
642 u64 aligned_data = 0;
643 bool signal = false;
644
645 if (pagecount > MAX_PAGE_BUFFER_COUNT)
646 return -EINVAL;
647
648
649 /*
650 * Adjust the size down since vmbus_channel_packet_page_buffer is the
651 * largest size we support
652 */
653 descsize = sizeof(struct vmbus_channel_packet_page_buffer) -
654 ((MAX_PAGE_BUFFER_COUNT - pagecount) *
655 sizeof(struct hv_page_buffer));
656 packetlen = descsize + bufferlen;
657 packetlen_aligned = ALIGN(packetlen, sizeof(u64));
658
659 /* Setup the descriptor */
660 desc.type = VM_PKT_DATA_USING_GPA_DIRECT;
661 desc.flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
662 desc.dataoffset8 = descsize >> 3; /* in 8-bytes grandularity */
663 desc.length8 = (u16)(packetlen_aligned >> 3);
664 desc.transactionid = requestid;
665 desc.rangecount = pagecount;
666
667 for (i = 0; i < pagecount; i++) {
668 desc.range[i].len = pagebuffers[i].len;
669 desc.range[i].offset = pagebuffers[i].offset;
670 desc.range[i].pfn = pagebuffers[i].pfn;
671 }
672
673 bufferlist[0].iov_base = &desc;
674 bufferlist[0].iov_len = descsize;
675 bufferlist[1].iov_base = buffer;
676 bufferlist[1].iov_len = bufferlen;
677 bufferlist[2].iov_base = &aligned_data;
678 bufferlist[2].iov_len = (packetlen_aligned - packetlen);
679
680 ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
681
682 if (ret == 0 && signal)
683 vmbus_setevent(channel);
684
685 return ret;
686 }
687 EXPORT_SYMBOL_GPL(vmbus_sendpacket_pagebuffer);
688
689 /*
690 * vmbus_sendpacket_multipagebuffer - Send a multi-page buffer packet
691 * using a GPADL Direct packet type.
692 */
vmbus_sendpacket_multipagebuffer(struct vmbus_channel * channel,struct hv_multipage_buffer * multi_pagebuffer,void * buffer,u32 bufferlen,u64 requestid)693 int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel,
694 struct hv_multipage_buffer *multi_pagebuffer,
695 void *buffer, u32 bufferlen, u64 requestid)
696 {
697 int ret;
698 struct vmbus_channel_packet_multipage_buffer desc;
699 u32 descsize;
700 u32 packetlen;
701 u32 packetlen_aligned;
702 struct kvec bufferlist[3];
703 u64 aligned_data = 0;
704 bool signal = false;
705 u32 pfncount = NUM_PAGES_SPANNED(multi_pagebuffer->offset,
706 multi_pagebuffer->len);
707
708 if (pfncount > MAX_MULTIPAGE_BUFFER_COUNT)
709 return -EINVAL;
710
711 /*
712 * Adjust the size down since vmbus_channel_packet_multipage_buffer is
713 * the largest size we support
714 */
715 descsize = sizeof(struct vmbus_channel_packet_multipage_buffer) -
716 ((MAX_MULTIPAGE_BUFFER_COUNT - pfncount) *
717 sizeof(u64));
718 packetlen = descsize + bufferlen;
719 packetlen_aligned = ALIGN(packetlen, sizeof(u64));
720
721
722 /* Setup the descriptor */
723 desc.type = VM_PKT_DATA_USING_GPA_DIRECT;
724 desc.flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
725 desc.dataoffset8 = descsize >> 3; /* in 8-bytes grandularity */
726 desc.length8 = (u16)(packetlen_aligned >> 3);
727 desc.transactionid = requestid;
728 desc.rangecount = 1;
729
730 desc.range.len = multi_pagebuffer->len;
731 desc.range.offset = multi_pagebuffer->offset;
732
733 memcpy(desc.range.pfn_array, multi_pagebuffer->pfn_array,
734 pfncount * sizeof(u64));
735
736 bufferlist[0].iov_base = &desc;
737 bufferlist[0].iov_len = descsize;
738 bufferlist[1].iov_base = buffer;
739 bufferlist[1].iov_len = bufferlen;
740 bufferlist[2].iov_base = &aligned_data;
741 bufferlist[2].iov_len = (packetlen_aligned - packetlen);
742
743 ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
744
745 if (ret == 0 && signal)
746 vmbus_setevent(channel);
747
748 return ret;
749 }
750 EXPORT_SYMBOL_GPL(vmbus_sendpacket_multipagebuffer);
751
752 /**
753 * vmbus_recvpacket() - Retrieve the user packet on the specified channel
754 * @channel: Pointer to vmbus_channel structure.
755 * @buffer: Pointer to the buffer you want to receive the data into.
756 * @bufferlen: Maximum size of what the the buffer will hold
757 * @buffer_actual_len: The actual size of the data after it was received
758 * @requestid: Identifier of the request
759 *
760 * Receives directly from the hyper-v vmbus and puts the data it received
761 * into Buffer. This will receive the data unparsed from hyper-v.
762 *
763 * Mainly used by Hyper-V drivers.
764 */
vmbus_recvpacket(struct vmbus_channel * channel,void * buffer,u32 bufferlen,u32 * buffer_actual_len,u64 * requestid)765 int vmbus_recvpacket(struct vmbus_channel *channel, void *buffer,
766 u32 bufferlen, u32 *buffer_actual_len, u64 *requestid)
767 {
768 struct vmpacket_descriptor desc;
769 u32 packetlen;
770 u32 userlen;
771 int ret;
772 bool signal = false;
773
774 *buffer_actual_len = 0;
775 *requestid = 0;
776
777
778 ret = hv_ringbuffer_peek(&channel->inbound, &desc,
779 sizeof(struct vmpacket_descriptor));
780 if (ret != 0)
781 return 0;
782
783 packetlen = desc.len8 << 3;
784 userlen = packetlen - (desc.offset8 << 3);
785
786 *buffer_actual_len = userlen;
787
788 if (userlen > bufferlen) {
789
790 pr_err("Buffer too small - got %d needs %d\n",
791 bufferlen, userlen);
792 return -ETOOSMALL;
793 }
794
795 *requestid = desc.trans_id;
796
797 /* Copy over the packet to the user buffer */
798 ret = hv_ringbuffer_read(&channel->inbound, buffer, userlen,
799 (desc.offset8 << 3), &signal);
800
801 if (signal)
802 vmbus_setevent(channel);
803
804 return 0;
805 }
806 EXPORT_SYMBOL(vmbus_recvpacket);
807
808 /*
809 * vmbus_recvpacket_raw - Retrieve the raw packet on the specified channel
810 */
vmbus_recvpacket_raw(struct vmbus_channel * channel,void * buffer,u32 bufferlen,u32 * buffer_actual_len,u64 * requestid)811 int vmbus_recvpacket_raw(struct vmbus_channel *channel, void *buffer,
812 u32 bufferlen, u32 *buffer_actual_len,
813 u64 *requestid)
814 {
815 struct vmpacket_descriptor desc;
816 u32 packetlen;
817 int ret;
818 bool signal = false;
819
820 *buffer_actual_len = 0;
821 *requestid = 0;
822
823
824 ret = hv_ringbuffer_peek(&channel->inbound, &desc,
825 sizeof(struct vmpacket_descriptor));
826 if (ret != 0)
827 return 0;
828
829
830 packetlen = desc.len8 << 3;
831
832 *buffer_actual_len = packetlen;
833
834 if (packetlen > bufferlen)
835 return -ENOBUFS;
836
837 *requestid = desc.trans_id;
838
839 /* Copy over the entire packet to the user buffer */
840 ret = hv_ringbuffer_read(&channel->inbound, buffer, packetlen, 0,
841 &signal);
842
843 if (signal)
844 vmbus_setevent(channel);
845
846 return ret;
847 }
848 EXPORT_SYMBOL_GPL(vmbus_recvpacket_raw);
849