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
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 /* Internal routines */
37 static int create_gpadl_header(
38 void *kbuffer, /* must be phys and virt contiguous */
39 u32 size, /* page-size multiple */
40 struct vmbus_channel_msginfo **msginfo,
41 u32 *messagecount);
42 static void vmbus_setevent(struct vmbus_channel *channel);
43
44 /*
45 * vmbus_setevent- Trigger an event notification on the specified
46 * channel.
47 */
vmbus_setevent(struct vmbus_channel * channel)48 static void vmbus_setevent(struct vmbus_channel *channel)
49 {
50 struct hv_monitor_page *monitorpage;
51
52 if (channel->offermsg.monitor_allocated) {
53 /* Each u32 represents 32 channels */
54 sync_set_bit(channel->offermsg.child_relid & 31,
55 (unsigned long *) vmbus_connection.send_int_page +
56 (channel->offermsg.child_relid >> 5));
57
58 monitorpage = vmbus_connection.monitor_pages;
59 monitorpage++; /* Get the child to parent monitor page */
60
61 sync_set_bit(channel->monitor_bit,
62 (unsigned long *)&monitorpage->trigger_group
63 [channel->monitor_grp].pending);
64
65 } else {
66 vmbus_set_event(channel->offermsg.child_relid);
67 }
68 }
69
70 /*
71 * vmbus_get_debug_info -Retrieve various channel debug info
72 */
vmbus_get_debug_info(struct vmbus_channel * channel,struct vmbus_channel_debug_info * debuginfo)73 void vmbus_get_debug_info(struct vmbus_channel *channel,
74 struct vmbus_channel_debug_info *debuginfo)
75 {
76 struct hv_monitor_page *monitorpage;
77 u8 monitor_group = (u8)channel->offermsg.monitorid / 32;
78 u8 monitor_offset = (u8)channel->offermsg.monitorid % 32;
79
80 debuginfo->relid = channel->offermsg.child_relid;
81 debuginfo->state = channel->state;
82 memcpy(&debuginfo->interfacetype,
83 &channel->offermsg.offer.if_type, sizeof(uuid_le));
84 memcpy(&debuginfo->interface_instance,
85 &channel->offermsg.offer.if_instance,
86 sizeof(uuid_le));
87
88 monitorpage = (struct hv_monitor_page *)vmbus_connection.monitor_pages;
89
90 debuginfo->monitorid = channel->offermsg.monitorid;
91
92 debuginfo->servermonitor_pending =
93 monitorpage->trigger_group[monitor_group].pending;
94 debuginfo->servermonitor_latency =
95 monitorpage->latency[monitor_group][monitor_offset];
96 debuginfo->servermonitor_connectionid =
97 monitorpage->parameter[monitor_group]
98 [monitor_offset].connectionid.u.id;
99
100 monitorpage++;
101
102 debuginfo->clientmonitor_pending =
103 monitorpage->trigger_group[monitor_group].pending;
104 debuginfo->clientmonitor_latency =
105 monitorpage->latency[monitor_group][monitor_offset];
106 debuginfo->clientmonitor_connectionid =
107 monitorpage->parameter[monitor_group]
108 [monitor_offset].connectionid.u.id;
109
110 hv_ringbuffer_get_debuginfo(&channel->inbound, &debuginfo->inbound);
111 hv_ringbuffer_get_debuginfo(&channel->outbound, &debuginfo->outbound);
112 }
113
114 /*
115 * vmbus_open - Open the specified channel.
116 */
vmbus_open(struct vmbus_channel * newchannel,u32 send_ringbuffer_size,u32 recv_ringbuffer_size,void * userdata,u32 userdatalen,void (* onchannelcallback)(void * context),void * context)117 int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size,
118 u32 recv_ringbuffer_size, void *userdata, u32 userdatalen,
119 void (*onchannelcallback)(void *context), void *context)
120 {
121 struct vmbus_channel_open_channel *open_msg;
122 struct vmbus_channel_msginfo *open_info = NULL;
123 void *in, *out;
124 unsigned long flags;
125 int ret, t, err = 0;
126
127 newchannel->onchannel_callback = onchannelcallback;
128 newchannel->channel_callback_context = context;
129
130 /* Allocate the ring buffer */
131 out = (void *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
132 get_order(send_ringbuffer_size + recv_ringbuffer_size));
133
134 if (!out)
135 return -ENOMEM;
136
137
138 in = (void *)((unsigned long)out + send_ringbuffer_size);
139
140 newchannel->ringbuffer_pages = out;
141 newchannel->ringbuffer_pagecount = (send_ringbuffer_size +
142 recv_ringbuffer_size) >> PAGE_SHIFT;
143
144 ret = hv_ringbuffer_init(
145 &newchannel->outbound, out, send_ringbuffer_size);
146
147 if (ret != 0) {
148 err = ret;
149 goto error0;
150 }
151
152 ret = hv_ringbuffer_init(
153 &newchannel->inbound, in, recv_ringbuffer_size);
154 if (ret != 0) {
155 err = ret;
156 goto error0;
157 }
158
159
160 /* Establish the gpadl for the ring buffer */
161 newchannel->ringbuffer_gpadlhandle = 0;
162
163 ret = vmbus_establish_gpadl(newchannel,
164 newchannel->outbound.ring_buffer,
165 send_ringbuffer_size +
166 recv_ringbuffer_size,
167 &newchannel->ringbuffer_gpadlhandle);
168
169 if (ret != 0) {
170 err = ret;
171 goto error0;
172 }
173
174 /* Create and init the channel open message */
175 open_info = kmalloc(sizeof(*open_info) +
176 sizeof(struct vmbus_channel_open_channel),
177 GFP_KERNEL);
178 if (!open_info) {
179 err = -ENOMEM;
180 goto error0;
181 }
182
183 init_completion(&open_info->waitevent);
184
185 open_msg = (struct vmbus_channel_open_channel *)open_info->msg;
186 open_msg->header.msgtype = CHANNELMSG_OPENCHANNEL;
187 open_msg->openid = newchannel->offermsg.child_relid;
188 open_msg->child_relid = newchannel->offermsg.child_relid;
189 open_msg->ringbuffer_gpadlhandle = newchannel->ringbuffer_gpadlhandle;
190 open_msg->downstream_ringbuffer_pageoffset = send_ringbuffer_size >>
191 PAGE_SHIFT;
192 open_msg->server_contextarea_gpadlhandle = 0;
193
194 if (userdatalen > MAX_USER_DEFINED_BYTES) {
195 err = -EINVAL;
196 goto error0;
197 }
198
199 if (userdatalen)
200 memcpy(open_msg->userdata, userdata, userdatalen);
201
202 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
203 list_add_tail(&open_info->msglistentry,
204 &vmbus_connection.chn_msg_list);
205 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
206
207 ret = vmbus_post_msg(open_msg,
208 sizeof(struct vmbus_channel_open_channel));
209
210 if (ret != 0)
211 goto error1;
212
213 t = wait_for_completion_timeout(&open_info->waitevent, 5*HZ);
214 if (t == 0) {
215 err = -ETIMEDOUT;
216 goto error1;
217 }
218
219
220 if (open_info->response.open_result.status)
221 err = open_info->response.open_result.status;
222
223 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
224 list_del(&open_info->msglistentry);
225 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
226
227 kfree(open_info);
228 return err;
229
230 error1:
231 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
232 list_del(&open_info->msglistentry);
233 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
234
235 error0:
236 free_pages((unsigned long)out,
237 get_order(send_ringbuffer_size + recv_ringbuffer_size));
238 kfree(open_info);
239 return err;
240 }
241 EXPORT_SYMBOL_GPL(vmbus_open);
242
243 /*
244 * create_gpadl_header - Creates a gpadl for the specified buffer
245 */
create_gpadl_header(void * kbuffer,u32 size,struct vmbus_channel_msginfo ** msginfo,u32 * messagecount)246 static int create_gpadl_header(void *kbuffer, u32 size,
247 struct vmbus_channel_msginfo **msginfo,
248 u32 *messagecount)
249 {
250 int i;
251 int pagecount;
252 unsigned long long pfn;
253 struct vmbus_channel_gpadl_header *gpadl_header;
254 struct vmbus_channel_gpadl_body *gpadl_body;
255 struct vmbus_channel_msginfo *msgheader;
256 struct vmbus_channel_msginfo *msgbody = NULL;
257 u32 msgsize;
258
259 int pfnsum, pfncount, pfnleft, pfncurr, pfnsize;
260
261 pagecount = size >> PAGE_SHIFT;
262 pfn = virt_to_phys(kbuffer) >> PAGE_SHIFT;
263
264 /* do we need a gpadl body msg */
265 pfnsize = MAX_SIZE_CHANNEL_MESSAGE -
266 sizeof(struct vmbus_channel_gpadl_header) -
267 sizeof(struct gpa_range);
268 pfncount = pfnsize / sizeof(u64);
269
270 if (pagecount > pfncount) {
271 /* we need a gpadl body */
272 /* fill in the header */
273 msgsize = sizeof(struct vmbus_channel_msginfo) +
274 sizeof(struct vmbus_channel_gpadl_header) +
275 sizeof(struct gpa_range) + pfncount * sizeof(u64);
276 msgheader = kzalloc(msgsize, GFP_KERNEL);
277 if (!msgheader)
278 goto nomem;
279
280 INIT_LIST_HEAD(&msgheader->submsglist);
281 msgheader->msgsize = msgsize;
282
283 gpadl_header = (struct vmbus_channel_gpadl_header *)
284 msgheader->msg;
285 gpadl_header->rangecount = 1;
286 gpadl_header->range_buflen = sizeof(struct gpa_range) +
287 pagecount * sizeof(u64);
288 gpadl_header->range[0].byte_offset = 0;
289 gpadl_header->range[0].byte_count = size;
290 for (i = 0; i < pfncount; i++)
291 gpadl_header->range[0].pfn_array[i] = pfn+i;
292 *msginfo = msgheader;
293 *messagecount = 1;
294
295 pfnsum = pfncount;
296 pfnleft = pagecount - pfncount;
297
298 /* how many pfns can we fit */
299 pfnsize = MAX_SIZE_CHANNEL_MESSAGE -
300 sizeof(struct vmbus_channel_gpadl_body);
301 pfncount = pfnsize / sizeof(u64);
302
303 /* fill in the body */
304 while (pfnleft) {
305 if (pfnleft > pfncount)
306 pfncurr = pfncount;
307 else
308 pfncurr = pfnleft;
309
310 msgsize = sizeof(struct vmbus_channel_msginfo) +
311 sizeof(struct vmbus_channel_gpadl_body) +
312 pfncurr * sizeof(u64);
313 msgbody = kzalloc(msgsize, GFP_KERNEL);
314
315 if (!msgbody) {
316 struct vmbus_channel_msginfo *pos = NULL;
317 struct vmbus_channel_msginfo *tmp = NULL;
318 /*
319 * Free up all the allocated messages.
320 */
321 list_for_each_entry_safe(pos, tmp,
322 &msgheader->submsglist,
323 msglistentry) {
324
325 list_del(&pos->msglistentry);
326 kfree(pos);
327 }
328
329 goto nomem;
330 }
331
332 msgbody->msgsize = msgsize;
333 (*messagecount)++;
334 gpadl_body =
335 (struct vmbus_channel_gpadl_body *)msgbody->msg;
336
337 /*
338 * Gpadl is u32 and we are using a pointer which could
339 * be 64-bit
340 * This is governed by the guest/host protocol and
341 * so the hypervisor gurantees that this is ok.
342 */
343 for (i = 0; i < pfncurr; i++)
344 gpadl_body->pfn[i] = pfn + pfnsum + i;
345
346 /* add to msg header */
347 list_add_tail(&msgbody->msglistentry,
348 &msgheader->submsglist);
349 pfnsum += pfncurr;
350 pfnleft -= pfncurr;
351 }
352 } else {
353 /* everything fits in a header */
354 msgsize = sizeof(struct vmbus_channel_msginfo) +
355 sizeof(struct vmbus_channel_gpadl_header) +
356 sizeof(struct gpa_range) + pagecount * sizeof(u64);
357 msgheader = kzalloc(msgsize, GFP_KERNEL);
358 if (msgheader == NULL)
359 goto nomem;
360 msgheader->msgsize = msgsize;
361
362 gpadl_header = (struct vmbus_channel_gpadl_header *)
363 msgheader->msg;
364 gpadl_header->rangecount = 1;
365 gpadl_header->range_buflen = sizeof(struct gpa_range) +
366 pagecount * sizeof(u64);
367 gpadl_header->range[0].byte_offset = 0;
368 gpadl_header->range[0].byte_count = size;
369 for (i = 0; i < pagecount; i++)
370 gpadl_header->range[0].pfn_array[i] = pfn+i;
371
372 *msginfo = msgheader;
373 *messagecount = 1;
374 }
375
376 return 0;
377 nomem:
378 kfree(msgheader);
379 kfree(msgbody);
380 return -ENOMEM;
381 }
382
383 /*
384 * vmbus_establish_gpadl - Estabish a GPADL for the specified buffer
385 *
386 * @channel: a channel
387 * @kbuffer: from kmalloc
388 * @size: page-size multiple
389 * @gpadl_handle: some funky thing
390 */
vmbus_establish_gpadl(struct vmbus_channel * channel,void * kbuffer,u32 size,u32 * gpadl_handle)391 int vmbus_establish_gpadl(struct vmbus_channel *channel, void *kbuffer,
392 u32 size, u32 *gpadl_handle)
393 {
394 struct vmbus_channel_gpadl_header *gpadlmsg;
395 struct vmbus_channel_gpadl_body *gpadl_body;
396 struct vmbus_channel_msginfo *msginfo = NULL;
397 struct vmbus_channel_msginfo *submsginfo;
398 u32 msgcount;
399 struct list_head *curr;
400 u32 next_gpadl_handle;
401 unsigned long flags;
402 int ret = 0;
403 int t;
404
405 next_gpadl_handle = atomic_read(&vmbus_connection.next_gpadl_handle);
406 atomic_inc(&vmbus_connection.next_gpadl_handle);
407
408 ret = create_gpadl_header(kbuffer, size, &msginfo, &msgcount);
409 if (ret)
410 return ret;
411
412 init_completion(&msginfo->waitevent);
413
414 gpadlmsg = (struct vmbus_channel_gpadl_header *)msginfo->msg;
415 gpadlmsg->header.msgtype = CHANNELMSG_GPADL_HEADER;
416 gpadlmsg->child_relid = channel->offermsg.child_relid;
417 gpadlmsg->gpadl = next_gpadl_handle;
418
419
420 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
421 list_add_tail(&msginfo->msglistentry,
422 &vmbus_connection.chn_msg_list);
423
424 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
425
426 ret = vmbus_post_msg(gpadlmsg, msginfo->msgsize -
427 sizeof(*msginfo));
428 if (ret != 0)
429 goto cleanup;
430
431 if (msgcount > 1) {
432 list_for_each(curr, &msginfo->submsglist) {
433
434 submsginfo = (struct vmbus_channel_msginfo *)curr;
435 gpadl_body =
436 (struct vmbus_channel_gpadl_body *)submsginfo->msg;
437
438 gpadl_body->header.msgtype =
439 CHANNELMSG_GPADL_BODY;
440 gpadl_body->gpadl = next_gpadl_handle;
441
442 ret = vmbus_post_msg(gpadl_body,
443 submsginfo->msgsize -
444 sizeof(*submsginfo));
445 if (ret != 0)
446 goto cleanup;
447
448 }
449 }
450 t = wait_for_completion_timeout(&msginfo->waitevent, 5*HZ);
451 BUG_ON(t == 0);
452
453
454 /* At this point, we received the gpadl created msg */
455 *gpadl_handle = gpadlmsg->gpadl;
456
457 cleanup:
458 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
459 list_del(&msginfo->msglistentry);
460 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
461
462 kfree(msginfo);
463 return ret;
464 }
465 EXPORT_SYMBOL_GPL(vmbus_establish_gpadl);
466
467 /*
468 * vmbus_teardown_gpadl -Teardown the specified GPADL handle
469 */
vmbus_teardown_gpadl(struct vmbus_channel * channel,u32 gpadl_handle)470 int vmbus_teardown_gpadl(struct vmbus_channel *channel, u32 gpadl_handle)
471 {
472 struct vmbus_channel_gpadl_teardown *msg;
473 struct vmbus_channel_msginfo *info;
474 unsigned long flags;
475 int ret, t;
476
477 info = kmalloc(sizeof(*info) +
478 sizeof(struct vmbus_channel_gpadl_teardown), GFP_KERNEL);
479 if (!info)
480 return -ENOMEM;
481
482 init_completion(&info->waitevent);
483
484 msg = (struct vmbus_channel_gpadl_teardown *)info->msg;
485
486 msg->header.msgtype = CHANNELMSG_GPADL_TEARDOWN;
487 msg->child_relid = channel->offermsg.child_relid;
488 msg->gpadl = gpadl_handle;
489
490 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
491 list_add_tail(&info->msglistentry,
492 &vmbus_connection.chn_msg_list);
493 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
494 ret = vmbus_post_msg(msg,
495 sizeof(struct vmbus_channel_gpadl_teardown));
496
497 BUG_ON(ret != 0);
498 t = wait_for_completion_timeout(&info->waitevent, 5*HZ);
499 BUG_ON(t == 0);
500
501 /* Received a torndown response */
502 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
503 list_del(&info->msglistentry);
504 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
505
506 kfree(info);
507 return ret;
508 }
509 EXPORT_SYMBOL_GPL(vmbus_teardown_gpadl);
510
511 /*
512 * vmbus_close - Close the specified channel
513 */
vmbus_close(struct vmbus_channel * channel)514 void vmbus_close(struct vmbus_channel *channel)
515 {
516 struct vmbus_channel_close_channel *msg;
517 int ret;
518 unsigned long flags;
519
520 /* Stop callback and cancel the timer asap */
521 spin_lock_irqsave(&channel->inbound_lock, flags);
522 channel->onchannel_callback = NULL;
523 spin_unlock_irqrestore(&channel->inbound_lock, flags);
524
525 /* Send a closing message */
526
527 msg = &channel->close_msg.msg;
528
529 msg->header.msgtype = CHANNELMSG_CLOSECHANNEL;
530 msg->child_relid = channel->offermsg.child_relid;
531
532 ret = vmbus_post_msg(msg, sizeof(struct vmbus_channel_close_channel));
533
534 BUG_ON(ret != 0);
535 /* Tear down the gpadl for the channel's ring buffer */
536 if (channel->ringbuffer_gpadlhandle)
537 vmbus_teardown_gpadl(channel,
538 channel->ringbuffer_gpadlhandle);
539
540 /* Cleanup the ring buffers for this channel */
541 hv_ringbuffer_cleanup(&channel->outbound);
542 hv_ringbuffer_cleanup(&channel->inbound);
543
544 free_pages((unsigned long)channel->ringbuffer_pages,
545 get_order(channel->ringbuffer_pagecount * PAGE_SIZE));
546
547
548 }
549 EXPORT_SYMBOL_GPL(vmbus_close);
550
551 /**
552 * vmbus_sendpacket() - Send the specified buffer on the given channel
553 * @channel: Pointer to vmbus_channel structure.
554 * @buffer: Pointer to the buffer you want to receive the data into.
555 * @bufferlen: Maximum size of what the the buffer will hold
556 * @requestid: Identifier of the request
557 * @type: Type of packet that is being send e.g. negotiate, time
558 * packet etc.
559 *
560 * Sends data in @buffer directly to hyper-v via the vmbus
561 * This will send the data unparsed to hyper-v.
562 *
563 * Mainly used by Hyper-V drivers.
564 */
vmbus_sendpacket(struct vmbus_channel * channel,const void * buffer,u32 bufferlen,u64 requestid,enum vmbus_packet_type type,u32 flags)565 int vmbus_sendpacket(struct vmbus_channel *channel, const void *buffer,
566 u32 bufferlen, u64 requestid,
567 enum vmbus_packet_type type, u32 flags)
568 {
569 struct vmpacket_descriptor desc;
570 u32 packetlen = sizeof(struct vmpacket_descriptor) + bufferlen;
571 u32 packetlen_aligned = ALIGN(packetlen, sizeof(u64));
572 struct scatterlist bufferlist[3];
573 u64 aligned_data = 0;
574 int ret;
575
576
577 /* Setup the descriptor */
578 desc.type = type; /* VmbusPacketTypeDataInBand; */
579 desc.flags = flags; /* VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED; */
580 /* in 8-bytes granularity */
581 desc.offset8 = sizeof(struct vmpacket_descriptor) >> 3;
582 desc.len8 = (u16)(packetlen_aligned >> 3);
583 desc.trans_id = requestid;
584
585 sg_init_table(bufferlist, 3);
586 sg_set_buf(&bufferlist[0], &desc, sizeof(struct vmpacket_descriptor));
587 sg_set_buf(&bufferlist[1], buffer, bufferlen);
588 sg_set_buf(&bufferlist[2], &aligned_data,
589 packetlen_aligned - packetlen);
590
591 ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3);
592
593 if (ret == 0 && !hv_get_ringbuffer_interrupt_mask(&channel->outbound))
594 vmbus_setevent(channel);
595
596 return ret;
597 }
598 EXPORT_SYMBOL(vmbus_sendpacket);
599
600 /*
601 * vmbus_sendpacket_pagebuffer - Send a range of single-page buffer
602 * packets using a GPADL Direct packet type.
603 */
vmbus_sendpacket_pagebuffer(struct vmbus_channel * channel,struct hv_page_buffer pagebuffers[],u32 pagecount,void * buffer,u32 bufferlen,u64 requestid)604 int vmbus_sendpacket_pagebuffer(struct vmbus_channel *channel,
605 struct hv_page_buffer pagebuffers[],
606 u32 pagecount, void *buffer, u32 bufferlen,
607 u64 requestid)
608 {
609 int ret;
610 int i;
611 struct vmbus_channel_packet_page_buffer desc;
612 u32 descsize;
613 u32 packetlen;
614 u32 packetlen_aligned;
615 struct scatterlist bufferlist[3];
616 u64 aligned_data = 0;
617
618 if (pagecount > MAX_PAGE_BUFFER_COUNT)
619 return -EINVAL;
620
621
622 /*
623 * Adjust the size down since vmbus_channel_packet_page_buffer is the
624 * largest size we support
625 */
626 descsize = sizeof(struct vmbus_channel_packet_page_buffer) -
627 ((MAX_PAGE_BUFFER_COUNT - pagecount) *
628 sizeof(struct hv_page_buffer));
629 packetlen = descsize + bufferlen;
630 packetlen_aligned = ALIGN(packetlen, sizeof(u64));
631
632 /* Setup the descriptor */
633 desc.type = VM_PKT_DATA_USING_GPA_DIRECT;
634 desc.flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
635 desc.dataoffset8 = descsize >> 3; /* in 8-bytes grandularity */
636 desc.length8 = (u16)(packetlen_aligned >> 3);
637 desc.transactionid = requestid;
638 desc.rangecount = pagecount;
639
640 for (i = 0; i < pagecount; i++) {
641 desc.range[i].len = pagebuffers[i].len;
642 desc.range[i].offset = pagebuffers[i].offset;
643 desc.range[i].pfn = pagebuffers[i].pfn;
644 }
645
646 sg_init_table(bufferlist, 3);
647 sg_set_buf(&bufferlist[0], &desc, descsize);
648 sg_set_buf(&bufferlist[1], buffer, bufferlen);
649 sg_set_buf(&bufferlist[2], &aligned_data,
650 packetlen_aligned - packetlen);
651
652 ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3);
653
654 if (ret == 0 && !hv_get_ringbuffer_interrupt_mask(&channel->outbound))
655 vmbus_setevent(channel);
656
657 return ret;
658 }
659 EXPORT_SYMBOL_GPL(vmbus_sendpacket_pagebuffer);
660
661 /*
662 * vmbus_sendpacket_multipagebuffer - Send a multi-page buffer packet
663 * using a GPADL Direct packet type.
664 */
vmbus_sendpacket_multipagebuffer(struct vmbus_channel * channel,struct hv_multipage_buffer * multi_pagebuffer,void * buffer,u32 bufferlen,u64 requestid)665 int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel,
666 struct hv_multipage_buffer *multi_pagebuffer,
667 void *buffer, u32 bufferlen, u64 requestid)
668 {
669 int ret;
670 struct vmbus_channel_packet_multipage_buffer desc;
671 u32 descsize;
672 u32 packetlen;
673 u32 packetlen_aligned;
674 struct scatterlist bufferlist[3];
675 u64 aligned_data = 0;
676 u32 pfncount = NUM_PAGES_SPANNED(multi_pagebuffer->offset,
677 multi_pagebuffer->len);
678
679
680 if ((pfncount < 0) || (pfncount > MAX_MULTIPAGE_BUFFER_COUNT))
681 return -EINVAL;
682
683 /*
684 * Adjust the size down since vmbus_channel_packet_multipage_buffer is
685 * the largest size we support
686 */
687 descsize = sizeof(struct vmbus_channel_packet_multipage_buffer) -
688 ((MAX_MULTIPAGE_BUFFER_COUNT - pfncount) *
689 sizeof(u64));
690 packetlen = descsize + bufferlen;
691 packetlen_aligned = ALIGN(packetlen, sizeof(u64));
692
693
694 /* Setup the descriptor */
695 desc.type = VM_PKT_DATA_USING_GPA_DIRECT;
696 desc.flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
697 desc.dataoffset8 = descsize >> 3; /* in 8-bytes grandularity */
698 desc.length8 = (u16)(packetlen_aligned >> 3);
699 desc.transactionid = requestid;
700 desc.rangecount = 1;
701
702 desc.range.len = multi_pagebuffer->len;
703 desc.range.offset = multi_pagebuffer->offset;
704
705 memcpy(desc.range.pfn_array, multi_pagebuffer->pfn_array,
706 pfncount * sizeof(u64));
707
708 sg_init_table(bufferlist, 3);
709 sg_set_buf(&bufferlist[0], &desc, descsize);
710 sg_set_buf(&bufferlist[1], buffer, bufferlen);
711 sg_set_buf(&bufferlist[2], &aligned_data,
712 packetlen_aligned - packetlen);
713
714 ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3);
715
716 if (ret == 0 && !hv_get_ringbuffer_interrupt_mask(&channel->outbound))
717 vmbus_setevent(channel);
718
719 return ret;
720 }
721 EXPORT_SYMBOL_GPL(vmbus_sendpacket_multipagebuffer);
722
723 /**
724 * vmbus_recvpacket() - Retrieve the user packet on the specified channel
725 * @channel: Pointer to vmbus_channel structure.
726 * @buffer: Pointer to the buffer you want to receive the data into.
727 * @bufferlen: Maximum size of what the the buffer will hold
728 * @buffer_actual_len: The actual size of the data after it was received
729 * @requestid: Identifier of the request
730 *
731 * Receives directly from the hyper-v vmbus and puts the data it received
732 * into Buffer. This will receive the data unparsed from hyper-v.
733 *
734 * Mainly used by Hyper-V drivers.
735 */
vmbus_recvpacket(struct vmbus_channel * channel,void * buffer,u32 bufferlen,u32 * buffer_actual_len,u64 * requestid)736 int vmbus_recvpacket(struct vmbus_channel *channel, void *buffer,
737 u32 bufferlen, u32 *buffer_actual_len, u64 *requestid)
738 {
739 struct vmpacket_descriptor desc;
740 u32 packetlen;
741 u32 userlen;
742 int ret;
743
744 *buffer_actual_len = 0;
745 *requestid = 0;
746
747
748 ret = hv_ringbuffer_peek(&channel->inbound, &desc,
749 sizeof(struct vmpacket_descriptor));
750 if (ret != 0)
751 return 0;
752
753 packetlen = desc.len8 << 3;
754 userlen = packetlen - (desc.offset8 << 3);
755
756 *buffer_actual_len = userlen;
757
758 if (userlen > bufferlen) {
759
760 pr_err("Buffer too small - got %d needs %d\n",
761 bufferlen, userlen);
762 return -ETOOSMALL;
763 }
764
765 *requestid = desc.trans_id;
766
767 /* Copy over the packet to the user buffer */
768 ret = hv_ringbuffer_read(&channel->inbound, buffer, userlen,
769 (desc.offset8 << 3));
770
771
772 return 0;
773 }
774 EXPORT_SYMBOL(vmbus_recvpacket);
775
776 /*
777 * vmbus_recvpacket_raw - Retrieve the raw packet on the specified channel
778 */
vmbus_recvpacket_raw(struct vmbus_channel * channel,void * buffer,u32 bufferlen,u32 * buffer_actual_len,u64 * requestid)779 int vmbus_recvpacket_raw(struct vmbus_channel *channel, void *buffer,
780 u32 bufferlen, u32 *buffer_actual_len,
781 u64 *requestid)
782 {
783 struct vmpacket_descriptor desc;
784 u32 packetlen;
785 u32 userlen;
786 int ret;
787
788 *buffer_actual_len = 0;
789 *requestid = 0;
790
791
792 ret = hv_ringbuffer_peek(&channel->inbound, &desc,
793 sizeof(struct vmpacket_descriptor));
794 if (ret != 0)
795 return 0;
796
797
798 packetlen = desc.len8 << 3;
799 userlen = packetlen - (desc.offset8 << 3);
800
801 *buffer_actual_len = packetlen;
802
803 if (packetlen > bufferlen) {
804 pr_err("Buffer too small - needed %d bytes but "
805 "got space for only %d bytes\n",
806 packetlen, bufferlen);
807 return -ENOBUFS;
808 }
809
810 *requestid = desc.trans_id;
811
812 /* Copy over the entire packet to the user buffer */
813 ret = hv_ringbuffer_read(&channel->inbound, buffer, packetlen, 0);
814
815 return 0;
816 }
817 EXPORT_SYMBOL_GPL(vmbus_recvpacket_raw);
818