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 */ 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 */ 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 error0; 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 error0; 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 goto error1; 170 171 t = wait_for_completion_timeout(&open_info->waitevent, 5*HZ); 172 if (t == 0) { 173 err = -ETIMEDOUT; 174 goto error1; 175 } 176 177 178 if (open_info->response.open_result.status) 179 err = open_info->response.open_result.status; 180 181 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 182 list_del(&open_info->msglistentry); 183 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 184 185 if (err == 0) 186 newchannel->state = CHANNEL_OPENED_STATE; 187 188 kfree(open_info); 189 return err; 190 191 error1: 192 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 193 list_del(&open_info->msglistentry); 194 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 195 196 error0: 197 free_pages((unsigned long)out, 198 get_order(send_ringbuffer_size + recv_ringbuffer_size)); 199 kfree(open_info); 200 return err; 201 } 202 EXPORT_SYMBOL_GPL(vmbus_open); 203 204 /* 205 * create_gpadl_header - Creates a gpadl for the specified buffer 206 */ 207 static int create_gpadl_header(void *kbuffer, u32 size, 208 struct vmbus_channel_msginfo **msginfo, 209 u32 *messagecount) 210 { 211 int i; 212 int pagecount; 213 struct vmbus_channel_gpadl_header *gpadl_header; 214 struct vmbus_channel_gpadl_body *gpadl_body; 215 struct vmbus_channel_msginfo *msgheader; 216 struct vmbus_channel_msginfo *msgbody = NULL; 217 u32 msgsize; 218 219 int pfnsum, pfncount, pfnleft, pfncurr, pfnsize; 220 221 pagecount = size >> PAGE_SHIFT; 222 223 /* do we need a gpadl body msg */ 224 pfnsize = MAX_SIZE_CHANNEL_MESSAGE - 225 sizeof(struct vmbus_channel_gpadl_header) - 226 sizeof(struct gpa_range); 227 pfncount = pfnsize / sizeof(u64); 228 229 if (pagecount > pfncount) { 230 /* we need a gpadl body */ 231 /* fill in the header */ 232 msgsize = sizeof(struct vmbus_channel_msginfo) + 233 sizeof(struct vmbus_channel_gpadl_header) + 234 sizeof(struct gpa_range) + pfncount * sizeof(u64); 235 msgheader = kzalloc(msgsize, GFP_KERNEL); 236 if (!msgheader) 237 goto nomem; 238 239 INIT_LIST_HEAD(&msgheader->submsglist); 240 msgheader->msgsize = msgsize; 241 242 gpadl_header = (struct vmbus_channel_gpadl_header *) 243 msgheader->msg; 244 gpadl_header->rangecount = 1; 245 gpadl_header->range_buflen = sizeof(struct gpa_range) + 246 pagecount * sizeof(u64); 247 gpadl_header->range[0].byte_offset = 0; 248 gpadl_header->range[0].byte_count = size; 249 for (i = 0; i < pfncount; i++) 250 gpadl_header->range[0].pfn_array[i] = slow_virt_to_phys( 251 kbuffer + PAGE_SIZE * i) >> PAGE_SHIFT; 252 *msginfo = msgheader; 253 *messagecount = 1; 254 255 pfnsum = pfncount; 256 pfnleft = pagecount - pfncount; 257 258 /* how many pfns can we fit */ 259 pfnsize = MAX_SIZE_CHANNEL_MESSAGE - 260 sizeof(struct vmbus_channel_gpadl_body); 261 pfncount = pfnsize / sizeof(u64); 262 263 /* fill in the body */ 264 while (pfnleft) { 265 if (pfnleft > pfncount) 266 pfncurr = pfncount; 267 else 268 pfncurr = pfnleft; 269 270 msgsize = sizeof(struct vmbus_channel_msginfo) + 271 sizeof(struct vmbus_channel_gpadl_body) + 272 pfncurr * sizeof(u64); 273 msgbody = kzalloc(msgsize, GFP_KERNEL); 274 275 if (!msgbody) { 276 struct vmbus_channel_msginfo *pos = NULL; 277 struct vmbus_channel_msginfo *tmp = NULL; 278 /* 279 * Free up all the allocated messages. 280 */ 281 list_for_each_entry_safe(pos, tmp, 282 &msgheader->submsglist, 283 msglistentry) { 284 285 list_del(&pos->msglistentry); 286 kfree(pos); 287 } 288 289 goto nomem; 290 } 291 292 msgbody->msgsize = msgsize; 293 (*messagecount)++; 294 gpadl_body = 295 (struct vmbus_channel_gpadl_body *)msgbody->msg; 296 297 /* 298 * Gpadl is u32 and we are using a pointer which could 299 * be 64-bit 300 * This is governed by the guest/host protocol and 301 * so the hypervisor gurantees that this is ok. 302 */ 303 for (i = 0; i < pfncurr; i++) 304 gpadl_body->pfn[i] = slow_virt_to_phys( 305 kbuffer + PAGE_SIZE * (pfnsum + i)) >> 306 PAGE_SHIFT; 307 308 /* add to msg header */ 309 list_add_tail(&msgbody->msglistentry, 310 &msgheader->submsglist); 311 pfnsum += pfncurr; 312 pfnleft -= pfncurr; 313 } 314 } else { 315 /* everything fits in a header */ 316 msgsize = sizeof(struct vmbus_channel_msginfo) + 317 sizeof(struct vmbus_channel_gpadl_header) + 318 sizeof(struct gpa_range) + pagecount * sizeof(u64); 319 msgheader = kzalloc(msgsize, GFP_KERNEL); 320 if (msgheader == NULL) 321 goto nomem; 322 msgheader->msgsize = msgsize; 323 324 gpadl_header = (struct vmbus_channel_gpadl_header *) 325 msgheader->msg; 326 gpadl_header->rangecount = 1; 327 gpadl_header->range_buflen = sizeof(struct gpa_range) + 328 pagecount * sizeof(u64); 329 gpadl_header->range[0].byte_offset = 0; 330 gpadl_header->range[0].byte_count = size; 331 for (i = 0; i < pagecount; i++) 332 gpadl_header->range[0].pfn_array[i] = slow_virt_to_phys( 333 kbuffer + PAGE_SIZE * i) >> PAGE_SHIFT; 334 335 *msginfo = msgheader; 336 *messagecount = 1; 337 } 338 339 return 0; 340 nomem: 341 kfree(msgheader); 342 kfree(msgbody); 343 return -ENOMEM; 344 } 345 346 /* 347 * vmbus_establish_gpadl - Estabish a GPADL for the specified buffer 348 * 349 * @channel: a channel 350 * @kbuffer: from kmalloc or vmalloc 351 * @size: page-size multiple 352 * @gpadl_handle: some funky thing 353 */ 354 int vmbus_establish_gpadl(struct vmbus_channel *channel, void *kbuffer, 355 u32 size, u32 *gpadl_handle) 356 { 357 struct vmbus_channel_gpadl_header *gpadlmsg; 358 struct vmbus_channel_gpadl_body *gpadl_body; 359 struct vmbus_channel_msginfo *msginfo = NULL; 360 struct vmbus_channel_msginfo *submsginfo; 361 u32 msgcount; 362 struct list_head *curr; 363 u32 next_gpadl_handle; 364 unsigned long flags; 365 int ret = 0; 366 int t; 367 368 next_gpadl_handle = atomic_read(&vmbus_connection.next_gpadl_handle); 369 atomic_inc(&vmbus_connection.next_gpadl_handle); 370 371 ret = create_gpadl_header(kbuffer, size, &msginfo, &msgcount); 372 if (ret) 373 return ret; 374 375 init_completion(&msginfo->waitevent); 376 377 gpadlmsg = (struct vmbus_channel_gpadl_header *)msginfo->msg; 378 gpadlmsg->header.msgtype = CHANNELMSG_GPADL_HEADER; 379 gpadlmsg->child_relid = channel->offermsg.child_relid; 380 gpadlmsg->gpadl = next_gpadl_handle; 381 382 383 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 384 list_add_tail(&msginfo->msglistentry, 385 &vmbus_connection.chn_msg_list); 386 387 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 388 389 ret = vmbus_post_msg(gpadlmsg, msginfo->msgsize - 390 sizeof(*msginfo)); 391 if (ret != 0) 392 goto cleanup; 393 394 if (msgcount > 1) { 395 list_for_each(curr, &msginfo->submsglist) { 396 397 submsginfo = (struct vmbus_channel_msginfo *)curr; 398 gpadl_body = 399 (struct vmbus_channel_gpadl_body *)submsginfo->msg; 400 401 gpadl_body->header.msgtype = 402 CHANNELMSG_GPADL_BODY; 403 gpadl_body->gpadl = next_gpadl_handle; 404 405 ret = vmbus_post_msg(gpadl_body, 406 submsginfo->msgsize - 407 sizeof(*submsginfo)); 408 if (ret != 0) 409 goto cleanup; 410 411 } 412 } 413 t = wait_for_completion_timeout(&msginfo->waitevent, 5*HZ); 414 BUG_ON(t == 0); 415 416 417 /* At this point, we received the gpadl created msg */ 418 *gpadl_handle = gpadlmsg->gpadl; 419 420 cleanup: 421 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 422 list_del(&msginfo->msglistentry); 423 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 424 425 kfree(msginfo); 426 return ret; 427 } 428 EXPORT_SYMBOL_GPL(vmbus_establish_gpadl); 429 430 /* 431 * vmbus_teardown_gpadl -Teardown the specified GPADL handle 432 */ 433 int vmbus_teardown_gpadl(struct vmbus_channel *channel, u32 gpadl_handle) 434 { 435 struct vmbus_channel_gpadl_teardown *msg; 436 struct vmbus_channel_msginfo *info; 437 unsigned long flags; 438 int ret, t; 439 440 info = kmalloc(sizeof(*info) + 441 sizeof(struct vmbus_channel_gpadl_teardown), GFP_KERNEL); 442 if (!info) 443 return -ENOMEM; 444 445 init_completion(&info->waitevent); 446 447 msg = (struct vmbus_channel_gpadl_teardown *)info->msg; 448 449 msg->header.msgtype = CHANNELMSG_GPADL_TEARDOWN; 450 msg->child_relid = channel->offermsg.child_relid; 451 msg->gpadl = gpadl_handle; 452 453 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 454 list_add_tail(&info->msglistentry, 455 &vmbus_connection.chn_msg_list); 456 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 457 ret = vmbus_post_msg(msg, 458 sizeof(struct vmbus_channel_gpadl_teardown)); 459 460 BUG_ON(ret != 0); 461 t = wait_for_completion_timeout(&info->waitevent, 5*HZ); 462 BUG_ON(t == 0); 463 464 /* Received a torndown response */ 465 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 466 list_del(&info->msglistentry); 467 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 468 469 kfree(info); 470 return ret; 471 } 472 EXPORT_SYMBOL_GPL(vmbus_teardown_gpadl); 473 474 static void vmbus_close_internal(struct vmbus_channel *channel) 475 { 476 struct vmbus_channel_close_channel *msg; 477 int ret; 478 unsigned long flags; 479 480 channel->state = CHANNEL_OPEN_STATE; 481 channel->sc_creation_callback = NULL; 482 /* Stop callback and cancel the timer asap */ 483 spin_lock_irqsave(&channel->inbound_lock, flags); 484 channel->onchannel_callback = NULL; 485 spin_unlock_irqrestore(&channel->inbound_lock, flags); 486 487 /* Send a closing message */ 488 489 msg = &channel->close_msg.msg; 490 491 msg->header.msgtype = CHANNELMSG_CLOSECHANNEL; 492 msg->child_relid = channel->offermsg.child_relid; 493 494 ret = vmbus_post_msg(msg, sizeof(struct vmbus_channel_close_channel)); 495 496 BUG_ON(ret != 0); 497 /* Tear down the gpadl for the channel's ring buffer */ 498 if (channel->ringbuffer_gpadlhandle) 499 vmbus_teardown_gpadl(channel, 500 channel->ringbuffer_gpadlhandle); 501 502 /* Cleanup the ring buffers for this channel */ 503 hv_ringbuffer_cleanup(&channel->outbound); 504 hv_ringbuffer_cleanup(&channel->inbound); 505 506 free_pages((unsigned long)channel->ringbuffer_pages, 507 get_order(channel->ringbuffer_pagecount * PAGE_SIZE)); 508 509 510 } 511 512 /* 513 * vmbus_close - Close the specified channel 514 */ 515 void vmbus_close(struct vmbus_channel *channel) 516 { 517 struct list_head *cur, *tmp; 518 struct vmbus_channel *cur_channel; 519 520 if (channel->primary_channel != NULL) { 521 /* 522 * We will only close sub-channels when 523 * the primary is closed. 524 */ 525 return; 526 } 527 /* 528 * Close all the sub-channels first and then close the 529 * primary channel. 530 */ 531 list_for_each_safe(cur, tmp, &channel->sc_list) { 532 cur_channel = list_entry(cur, struct vmbus_channel, sc_list); 533 if (cur_channel->state != CHANNEL_OPENED_STATE) 534 continue; 535 vmbus_close_internal(cur_channel); 536 } 537 /* 538 * Now close the primary. 539 */ 540 vmbus_close_internal(channel); 541 } 542 EXPORT_SYMBOL_GPL(vmbus_close); 543 544 /** 545 * vmbus_sendpacket() - Send the specified buffer on the given channel 546 * @channel: Pointer to vmbus_channel structure. 547 * @buffer: Pointer to the buffer you want to receive the data into. 548 * @bufferlen: Maximum size of what the the buffer will hold 549 * @requestid: Identifier of the request 550 * @type: Type of packet that is being send e.g. negotiate, time 551 * packet etc. 552 * 553 * Sends data in @buffer directly to hyper-v via the vmbus 554 * This will send the data unparsed to hyper-v. 555 * 556 * Mainly used by Hyper-V drivers. 557 */ 558 int vmbus_sendpacket(struct vmbus_channel *channel, void *buffer, 559 u32 bufferlen, u64 requestid, 560 enum vmbus_packet_type type, u32 flags) 561 { 562 struct vmpacket_descriptor desc; 563 u32 packetlen = sizeof(struct vmpacket_descriptor) + bufferlen; 564 u32 packetlen_aligned = ALIGN(packetlen, sizeof(u64)); 565 struct kvec bufferlist[3]; 566 u64 aligned_data = 0; 567 int ret; 568 bool signal = false; 569 570 571 /* Setup the descriptor */ 572 desc.type = type; /* VmbusPacketTypeDataInBand; */ 573 desc.flags = flags; /* VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED; */ 574 /* in 8-bytes granularity */ 575 desc.offset8 = sizeof(struct vmpacket_descriptor) >> 3; 576 desc.len8 = (u16)(packetlen_aligned >> 3); 577 desc.trans_id = requestid; 578 579 bufferlist[0].iov_base = &desc; 580 bufferlist[0].iov_len = sizeof(struct vmpacket_descriptor); 581 bufferlist[1].iov_base = buffer; 582 bufferlist[1].iov_len = bufferlen; 583 bufferlist[2].iov_base = &aligned_data; 584 bufferlist[2].iov_len = (packetlen_aligned - packetlen); 585 586 ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal); 587 588 if (ret == 0 && signal) 589 vmbus_setevent(channel); 590 591 return ret; 592 } 593 EXPORT_SYMBOL(vmbus_sendpacket); 594 595 /* 596 * vmbus_sendpacket_pagebuffer - Send a range of single-page buffer 597 * packets using a GPADL Direct packet type. 598 */ 599 int vmbus_sendpacket_pagebuffer(struct vmbus_channel *channel, 600 struct hv_page_buffer pagebuffers[], 601 u32 pagecount, void *buffer, u32 bufferlen, 602 u64 requestid) 603 { 604 int ret; 605 int i; 606 struct vmbus_channel_packet_page_buffer desc; 607 u32 descsize; 608 u32 packetlen; 609 u32 packetlen_aligned; 610 struct kvec bufferlist[3]; 611 u64 aligned_data = 0; 612 bool signal = false; 613 614 if (pagecount > MAX_PAGE_BUFFER_COUNT) 615 return -EINVAL; 616 617 618 /* 619 * Adjust the size down since vmbus_channel_packet_page_buffer is the 620 * largest size we support 621 */ 622 descsize = sizeof(struct vmbus_channel_packet_page_buffer) - 623 ((MAX_PAGE_BUFFER_COUNT - pagecount) * 624 sizeof(struct hv_page_buffer)); 625 packetlen = descsize + bufferlen; 626 packetlen_aligned = ALIGN(packetlen, sizeof(u64)); 627 628 /* Setup the descriptor */ 629 desc.type = VM_PKT_DATA_USING_GPA_DIRECT; 630 desc.flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED; 631 desc.dataoffset8 = descsize >> 3; /* in 8-bytes grandularity */ 632 desc.length8 = (u16)(packetlen_aligned >> 3); 633 desc.transactionid = requestid; 634 desc.rangecount = pagecount; 635 636 for (i = 0; i < pagecount; i++) { 637 desc.range[i].len = pagebuffers[i].len; 638 desc.range[i].offset = pagebuffers[i].offset; 639 desc.range[i].pfn = pagebuffers[i].pfn; 640 } 641 642 bufferlist[0].iov_base = &desc; 643 bufferlist[0].iov_len = descsize; 644 bufferlist[1].iov_base = buffer; 645 bufferlist[1].iov_len = bufferlen; 646 bufferlist[2].iov_base = &aligned_data; 647 bufferlist[2].iov_len = (packetlen_aligned - packetlen); 648 649 ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal); 650 651 if (ret == 0 && signal) 652 vmbus_setevent(channel); 653 654 return ret; 655 } 656 EXPORT_SYMBOL_GPL(vmbus_sendpacket_pagebuffer); 657 658 /* 659 * vmbus_sendpacket_multipagebuffer - Send a multi-page buffer packet 660 * using a GPADL Direct packet type. 661 */ 662 int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel, 663 struct hv_multipage_buffer *multi_pagebuffer, 664 void *buffer, u32 bufferlen, u64 requestid) 665 { 666 int ret; 667 struct vmbus_channel_packet_multipage_buffer desc; 668 u32 descsize; 669 u32 packetlen; 670 u32 packetlen_aligned; 671 struct kvec bufferlist[3]; 672 u64 aligned_data = 0; 673 bool signal = false; 674 u32 pfncount = NUM_PAGES_SPANNED(multi_pagebuffer->offset, 675 multi_pagebuffer->len); 676 677 678 if ((pfncount < 0) || (pfncount > MAX_MULTIPAGE_BUFFER_COUNT)) 679 return -EINVAL; 680 681 /* 682 * Adjust the size down since vmbus_channel_packet_multipage_buffer is 683 * the largest size we support 684 */ 685 descsize = sizeof(struct vmbus_channel_packet_multipage_buffer) - 686 ((MAX_MULTIPAGE_BUFFER_COUNT - pfncount) * 687 sizeof(u64)); 688 packetlen = descsize + bufferlen; 689 packetlen_aligned = ALIGN(packetlen, sizeof(u64)); 690 691 692 /* Setup the descriptor */ 693 desc.type = VM_PKT_DATA_USING_GPA_DIRECT; 694 desc.flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED; 695 desc.dataoffset8 = descsize >> 3; /* in 8-bytes grandularity */ 696 desc.length8 = (u16)(packetlen_aligned >> 3); 697 desc.transactionid = requestid; 698 desc.rangecount = 1; 699 700 desc.range.len = multi_pagebuffer->len; 701 desc.range.offset = multi_pagebuffer->offset; 702 703 memcpy(desc.range.pfn_array, multi_pagebuffer->pfn_array, 704 pfncount * sizeof(u64)); 705 706 bufferlist[0].iov_base = &desc; 707 bufferlist[0].iov_len = descsize; 708 bufferlist[1].iov_base = buffer; 709 bufferlist[1].iov_len = bufferlen; 710 bufferlist[2].iov_base = &aligned_data; 711 bufferlist[2].iov_len = (packetlen_aligned - packetlen); 712 713 ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal); 714 715 if (ret == 0 && signal) 716 vmbus_setevent(channel); 717 718 return ret; 719 } 720 EXPORT_SYMBOL_GPL(vmbus_sendpacket_multipagebuffer); 721 722 /** 723 * vmbus_recvpacket() - Retrieve the user packet on the specified channel 724 * @channel: Pointer to vmbus_channel structure. 725 * @buffer: Pointer to the buffer you want to receive the data into. 726 * @bufferlen: Maximum size of what the the buffer will hold 727 * @buffer_actual_len: The actual size of the data after it was received 728 * @requestid: Identifier of the request 729 * 730 * Receives directly from the hyper-v vmbus and puts the data it received 731 * into Buffer. This will receive the data unparsed from hyper-v. 732 * 733 * Mainly used by Hyper-V drivers. 734 */ 735 int vmbus_recvpacket(struct vmbus_channel *channel, void *buffer, 736 u32 bufferlen, u32 *buffer_actual_len, u64 *requestid) 737 { 738 struct vmpacket_descriptor desc; 739 u32 packetlen; 740 u32 userlen; 741 int ret; 742 bool signal = false; 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), &signal); 770 771 if (signal) 772 vmbus_setevent(channel); 773 774 return 0; 775 } 776 EXPORT_SYMBOL(vmbus_recvpacket); 777 778 /* 779 * vmbus_recvpacket_raw - Retrieve the raw packet on the specified channel 780 */ 781 int vmbus_recvpacket_raw(struct vmbus_channel *channel, void *buffer, 782 u32 bufferlen, u32 *buffer_actual_len, 783 u64 *requestid) 784 { 785 struct vmpacket_descriptor desc; 786 u32 packetlen; 787 int ret; 788 bool signal = false; 789 790 *buffer_actual_len = 0; 791 *requestid = 0; 792 793 794 ret = hv_ringbuffer_peek(&channel->inbound, &desc, 795 sizeof(struct vmpacket_descriptor)); 796 if (ret != 0) 797 return 0; 798 799 800 packetlen = desc.len8 << 3; 801 802 *buffer_actual_len = packetlen; 803 804 if (packetlen > bufferlen) { 805 pr_err("Buffer too small - needed %d bytes but " 806 "got space for only %d bytes\n", 807 packetlen, bufferlen); 808 return -ENOBUFS; 809 } 810 811 *requestid = desc.trans_id; 812 813 /* Copy over the entire packet to the user buffer */ 814 ret = hv_ringbuffer_read(&channel->inbound, buffer, packetlen, 0, 815 &signal); 816 817 if (signal) 818 vmbus_setevent(channel); 819 820 return ret; 821 } 822 EXPORT_SYMBOL_GPL(vmbus_recvpacket_raw); 823