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/list.h> 29 #include <linux/module.h> 30 #include <linux/completion.h> 31 #include <linux/hyperv.h> 32 33 #include "hyperv_vmbus.h" 34 35 static void init_vp_index(struct vmbus_channel *channel, 36 const uuid_le *type_guid); 37 38 /** 39 * vmbus_prep_negotiate_resp() - Create default response for Hyper-V Negotiate message 40 * @icmsghdrp: Pointer to msg header structure 41 * @icmsg_negotiate: Pointer to negotiate message structure 42 * @buf: Raw buffer channel data 43 * 44 * @icmsghdrp is of type &struct icmsg_hdr. 45 * @negop is of type &struct icmsg_negotiate. 46 * Set up and fill in default negotiate response message. 47 * 48 * The fw_version specifies the framework version that 49 * we can support and srv_version specifies the service 50 * version we can support. 51 * 52 * Mainly used by Hyper-V drivers. 53 */ 54 bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp, 55 struct icmsg_negotiate *negop, u8 *buf, 56 int fw_version, int srv_version) 57 { 58 int icframe_major, icframe_minor; 59 int icmsg_major, icmsg_minor; 60 int fw_major, fw_minor; 61 int srv_major, srv_minor; 62 int i; 63 bool found_match = false; 64 65 icmsghdrp->icmsgsize = 0x10; 66 fw_major = (fw_version >> 16); 67 fw_minor = (fw_version & 0xFFFF); 68 69 srv_major = (srv_version >> 16); 70 srv_minor = (srv_version & 0xFFFF); 71 72 negop = (struct icmsg_negotiate *)&buf[ 73 sizeof(struct vmbuspipe_hdr) + 74 sizeof(struct icmsg_hdr)]; 75 76 icframe_major = negop->icframe_vercnt; 77 icframe_minor = 0; 78 79 icmsg_major = negop->icmsg_vercnt; 80 icmsg_minor = 0; 81 82 /* 83 * Select the framework version number we will 84 * support. 85 */ 86 87 for (i = 0; i < negop->icframe_vercnt; i++) { 88 if ((negop->icversion_data[i].major == fw_major) && 89 (negop->icversion_data[i].minor == fw_minor)) { 90 icframe_major = negop->icversion_data[i].major; 91 icframe_minor = negop->icversion_data[i].minor; 92 found_match = true; 93 } 94 } 95 96 if (!found_match) 97 goto fw_error; 98 99 found_match = false; 100 101 for (i = negop->icframe_vercnt; 102 (i < negop->icframe_vercnt + negop->icmsg_vercnt); i++) { 103 if ((negop->icversion_data[i].major == srv_major) && 104 (negop->icversion_data[i].minor == srv_minor)) { 105 icmsg_major = negop->icversion_data[i].major; 106 icmsg_minor = negop->icversion_data[i].minor; 107 found_match = true; 108 } 109 } 110 111 /* 112 * Respond with the framework and service 113 * version numbers we can support. 114 */ 115 116 fw_error: 117 if (!found_match) { 118 negop->icframe_vercnt = 0; 119 negop->icmsg_vercnt = 0; 120 } else { 121 negop->icframe_vercnt = 1; 122 negop->icmsg_vercnt = 1; 123 } 124 125 negop->icversion_data[0].major = icframe_major; 126 negop->icversion_data[0].minor = icframe_minor; 127 negop->icversion_data[1].major = icmsg_major; 128 negop->icversion_data[1].minor = icmsg_minor; 129 return found_match; 130 } 131 132 EXPORT_SYMBOL_GPL(vmbus_prep_negotiate_resp); 133 134 /* 135 * alloc_channel - Allocate and initialize a vmbus channel object 136 */ 137 static struct vmbus_channel *alloc_channel(void) 138 { 139 static atomic_t chan_num = ATOMIC_INIT(0); 140 struct vmbus_channel *channel; 141 142 channel = kzalloc(sizeof(*channel), GFP_ATOMIC); 143 if (!channel) 144 return NULL; 145 146 channel->id = atomic_inc_return(&chan_num); 147 spin_lock_init(&channel->inbound_lock); 148 spin_lock_init(&channel->lock); 149 150 INIT_LIST_HEAD(&channel->sc_list); 151 INIT_LIST_HEAD(&channel->percpu_list); 152 153 return channel; 154 } 155 156 /* 157 * free_channel - Release the resources used by the vmbus channel object 158 */ 159 static void free_channel(struct vmbus_channel *channel) 160 { 161 kfree(channel); 162 } 163 164 static void percpu_channel_enq(void *arg) 165 { 166 struct vmbus_channel *channel = arg; 167 int cpu = smp_processor_id(); 168 169 list_add_tail(&channel->percpu_list, &hv_context.percpu_list[cpu]); 170 } 171 172 static void percpu_channel_deq(void *arg) 173 { 174 struct vmbus_channel *channel = arg; 175 176 list_del(&channel->percpu_list); 177 } 178 179 180 void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid) 181 { 182 struct vmbus_channel_relid_released msg; 183 unsigned long flags; 184 struct vmbus_channel *primary_channel; 185 186 memset(&msg, 0, sizeof(struct vmbus_channel_relid_released)); 187 msg.child_relid = relid; 188 msg.header.msgtype = CHANNELMSG_RELID_RELEASED; 189 vmbus_post_msg(&msg, sizeof(struct vmbus_channel_relid_released)); 190 191 if (channel == NULL) 192 return; 193 194 if (channel->target_cpu != get_cpu()) { 195 put_cpu(); 196 smp_call_function_single(channel->target_cpu, 197 percpu_channel_deq, channel, true); 198 } else { 199 percpu_channel_deq(channel); 200 put_cpu(); 201 } 202 203 if (channel->primary_channel == NULL) { 204 spin_lock_irqsave(&vmbus_connection.channel_lock, flags); 205 list_del(&channel->listentry); 206 spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags); 207 208 primary_channel = channel; 209 } else { 210 primary_channel = channel->primary_channel; 211 spin_lock_irqsave(&primary_channel->lock, flags); 212 list_del(&channel->sc_list); 213 primary_channel->num_sc--; 214 spin_unlock_irqrestore(&primary_channel->lock, flags); 215 } 216 217 /* 218 * We need to free the bit for init_vp_index() to work in the case 219 * of sub-channel, when we reload drivers like hv_netvsc. 220 */ 221 cpumask_clear_cpu(channel->target_cpu, 222 &primary_channel->alloced_cpus_in_node); 223 224 free_channel(channel); 225 } 226 227 void vmbus_free_channels(void) 228 { 229 struct vmbus_channel *channel, *tmp; 230 231 list_for_each_entry_safe(channel, tmp, &vmbus_connection.chn_list, 232 listentry) { 233 /* if we don't set rescind to true, vmbus_close_internal() 234 * won't invoke hv_process_channel_removal(). 235 */ 236 channel->rescind = true; 237 238 vmbus_device_unregister(channel->device_obj); 239 } 240 } 241 242 /* 243 * vmbus_process_offer - Process the offer by creating a channel/device 244 * associated with this offer 245 */ 246 static void vmbus_process_offer(struct vmbus_channel *newchannel) 247 { 248 struct vmbus_channel *channel; 249 bool fnew = true; 250 unsigned long flags; 251 252 /* Make sure this is a new offer */ 253 spin_lock_irqsave(&vmbus_connection.channel_lock, flags); 254 255 list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) { 256 if (!uuid_le_cmp(channel->offermsg.offer.if_type, 257 newchannel->offermsg.offer.if_type) && 258 !uuid_le_cmp(channel->offermsg.offer.if_instance, 259 newchannel->offermsg.offer.if_instance)) { 260 fnew = false; 261 break; 262 } 263 } 264 265 if (fnew) 266 list_add_tail(&newchannel->listentry, 267 &vmbus_connection.chn_list); 268 269 spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags); 270 271 if (!fnew) { 272 /* 273 * Check to see if this is a sub-channel. 274 */ 275 if (newchannel->offermsg.offer.sub_channel_index != 0) { 276 /* 277 * Process the sub-channel. 278 */ 279 newchannel->primary_channel = channel; 280 spin_lock_irqsave(&channel->lock, flags); 281 list_add_tail(&newchannel->sc_list, &channel->sc_list); 282 channel->num_sc++; 283 spin_unlock_irqrestore(&channel->lock, flags); 284 } else 285 goto err_free_chan; 286 } 287 288 init_vp_index(newchannel, &newchannel->offermsg.offer.if_type); 289 290 if (newchannel->target_cpu != get_cpu()) { 291 put_cpu(); 292 smp_call_function_single(newchannel->target_cpu, 293 percpu_channel_enq, 294 newchannel, true); 295 } else { 296 percpu_channel_enq(newchannel); 297 put_cpu(); 298 } 299 300 /* 301 * This state is used to indicate a successful open 302 * so that when we do close the channel normally, we 303 * can cleanup properly 304 */ 305 newchannel->state = CHANNEL_OPEN_STATE; 306 307 if (!fnew) { 308 if (channel->sc_creation_callback != NULL) 309 channel->sc_creation_callback(newchannel); 310 return; 311 } 312 313 /* 314 * Start the process of binding this offer to the driver 315 * We need to set the DeviceObject field before calling 316 * vmbus_child_dev_add() 317 */ 318 newchannel->device_obj = vmbus_device_create( 319 &newchannel->offermsg.offer.if_type, 320 &newchannel->offermsg.offer.if_instance, 321 newchannel); 322 if (!newchannel->device_obj) 323 goto err_deq_chan; 324 325 /* 326 * Add the new device to the bus. This will kick off device-driver 327 * binding which eventually invokes the device driver's AddDevice() 328 * method. 329 */ 330 if (vmbus_device_register(newchannel->device_obj) != 0) { 331 pr_err("unable to add child device object (relid %d)\n", 332 newchannel->offermsg.child_relid); 333 kfree(newchannel->device_obj); 334 goto err_deq_chan; 335 } 336 return; 337 338 err_deq_chan: 339 spin_lock_irqsave(&vmbus_connection.channel_lock, flags); 340 list_del(&newchannel->listentry); 341 spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags); 342 343 if (newchannel->target_cpu != get_cpu()) { 344 put_cpu(); 345 smp_call_function_single(newchannel->target_cpu, 346 percpu_channel_deq, newchannel, true); 347 } else { 348 percpu_channel_deq(newchannel); 349 put_cpu(); 350 } 351 352 err_free_chan: 353 free_channel(newchannel); 354 } 355 356 enum { 357 IDE = 0, 358 SCSI, 359 NIC, 360 ND_NIC, 361 PCIE, 362 MAX_PERF_CHN, 363 }; 364 365 /* 366 * This is an array of device_ids (device types) that are performance critical. 367 * We attempt to distribute the interrupt load for these devices across 368 * all available CPUs. 369 */ 370 static const struct hv_vmbus_device_id hp_devs[] = { 371 /* IDE */ 372 { HV_IDE_GUID, }, 373 /* Storage - SCSI */ 374 { HV_SCSI_GUID, }, 375 /* Network */ 376 { HV_NIC_GUID, }, 377 /* NetworkDirect Guest RDMA */ 378 { HV_ND_GUID, }, 379 /* PCI Express Pass Through */ 380 { HV_PCIE_GUID, }, 381 }; 382 383 384 /* 385 * We use this state to statically distribute the channel interrupt load. 386 */ 387 static int next_numa_node_id; 388 389 /* 390 * Starting with Win8, we can statically distribute the incoming 391 * channel interrupt load by binding a channel to VCPU. 392 * We do this in a hierarchical fashion: 393 * First distribute the primary channels across available NUMA nodes 394 * and then distribute the subchannels amongst the CPUs in the NUMA 395 * node assigned to the primary channel. 396 * 397 * For pre-win8 hosts or non-performance critical channels we assign the 398 * first CPU in the first NUMA node. 399 */ 400 static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_guid) 401 { 402 u32 cur_cpu; 403 int i; 404 bool perf_chn = false; 405 struct vmbus_channel *primary = channel->primary_channel; 406 int next_node; 407 struct cpumask available_mask; 408 struct cpumask *alloced_mask; 409 410 for (i = IDE; i < MAX_PERF_CHN; i++) { 411 if (!uuid_le_cmp(*type_guid, hp_devs[i].guid)) { 412 perf_chn = true; 413 break; 414 } 415 } 416 if ((vmbus_proto_version == VERSION_WS2008) || 417 (vmbus_proto_version == VERSION_WIN7) || (!perf_chn)) { 418 /* 419 * Prior to win8, all channel interrupts are 420 * delivered on cpu 0. 421 * Also if the channel is not a performance critical 422 * channel, bind it to cpu 0. 423 */ 424 channel->numa_node = 0; 425 channel->target_cpu = 0; 426 channel->target_vp = hv_context.vp_index[0]; 427 return; 428 } 429 430 /* 431 * We distribute primary channels evenly across all the available 432 * NUMA nodes and within the assigned NUMA node we will assign the 433 * first available CPU to the primary channel. 434 * The sub-channels will be assigned to the CPUs available in the 435 * NUMA node evenly. 436 */ 437 if (!primary) { 438 while (true) { 439 next_node = next_numa_node_id++; 440 if (next_node == nr_node_ids) 441 next_node = next_numa_node_id = 0; 442 if (cpumask_empty(cpumask_of_node(next_node))) 443 continue; 444 break; 445 } 446 channel->numa_node = next_node; 447 primary = channel; 448 } 449 alloced_mask = &hv_context.hv_numa_map[primary->numa_node]; 450 451 if (cpumask_weight(alloced_mask) == 452 cpumask_weight(cpumask_of_node(primary->numa_node))) { 453 /* 454 * We have cycled through all the CPUs in the node; 455 * reset the alloced map. 456 */ 457 cpumask_clear(alloced_mask); 458 } 459 460 cpumask_xor(&available_mask, alloced_mask, 461 cpumask_of_node(primary->numa_node)); 462 463 cur_cpu = -1; 464 while (true) { 465 cur_cpu = cpumask_next(cur_cpu, &available_mask); 466 if (cur_cpu >= nr_cpu_ids) { 467 cur_cpu = -1; 468 cpumask_copy(&available_mask, 469 cpumask_of_node(primary->numa_node)); 470 continue; 471 } 472 473 /* 474 * NOTE: in the case of sub-channel, we clear the sub-channel 475 * related bit(s) in primary->alloced_cpus_in_node in 476 * hv_process_channel_removal(), so when we reload drivers 477 * like hv_netvsc in SMP guest, here we're able to re-allocate 478 * bit from primary->alloced_cpus_in_node. 479 */ 480 if (!cpumask_test_cpu(cur_cpu, 481 &primary->alloced_cpus_in_node)) { 482 cpumask_set_cpu(cur_cpu, 483 &primary->alloced_cpus_in_node); 484 cpumask_set_cpu(cur_cpu, alloced_mask); 485 break; 486 } 487 } 488 489 channel->target_cpu = cur_cpu; 490 channel->target_vp = hv_context.vp_index[cur_cpu]; 491 } 492 493 /* 494 * vmbus_unload_response - Handler for the unload response. 495 */ 496 static void vmbus_unload_response(struct vmbus_channel_message_header *hdr) 497 { 498 /* 499 * This is a global event; just wakeup the waiting thread. 500 * Once we successfully unload, we can cleanup the monitor state. 501 */ 502 complete(&vmbus_connection.unload_event); 503 } 504 505 void vmbus_initiate_unload(void) 506 { 507 struct vmbus_channel_message_header hdr; 508 509 /* Pre-Win2012R2 hosts don't support reconnect */ 510 if (vmbus_proto_version < VERSION_WIN8_1) 511 return; 512 513 init_completion(&vmbus_connection.unload_event); 514 memset(&hdr, 0, sizeof(struct vmbus_channel_message_header)); 515 hdr.msgtype = CHANNELMSG_UNLOAD; 516 vmbus_post_msg(&hdr, sizeof(struct vmbus_channel_message_header)); 517 518 wait_for_completion(&vmbus_connection.unload_event); 519 } 520 521 /* 522 * vmbus_onoffer - Handler for channel offers from vmbus in parent partition. 523 * 524 */ 525 static void vmbus_onoffer(struct vmbus_channel_message_header *hdr) 526 { 527 struct vmbus_channel_offer_channel *offer; 528 struct vmbus_channel *newchannel; 529 530 offer = (struct vmbus_channel_offer_channel *)hdr; 531 532 /* Allocate the channel object and save this offer. */ 533 newchannel = alloc_channel(); 534 if (!newchannel) { 535 pr_err("Unable to allocate channel object\n"); 536 return; 537 } 538 539 /* 540 * By default we setup state to enable batched 541 * reading. A specific service can choose to 542 * disable this prior to opening the channel. 543 */ 544 newchannel->batched_reading = true; 545 546 /* 547 * Setup state for signalling the host. 548 */ 549 newchannel->sig_event = (struct hv_input_signal_event *) 550 (ALIGN((unsigned long) 551 &newchannel->sig_buf, 552 HV_HYPERCALL_PARAM_ALIGN)); 553 554 newchannel->sig_event->connectionid.asu32 = 0; 555 newchannel->sig_event->connectionid.u.id = VMBUS_EVENT_CONNECTION_ID; 556 newchannel->sig_event->flag_number = 0; 557 newchannel->sig_event->rsvdz = 0; 558 559 if (vmbus_proto_version != VERSION_WS2008) { 560 newchannel->is_dedicated_interrupt = 561 (offer->is_dedicated_interrupt != 0); 562 newchannel->sig_event->connectionid.u.id = 563 offer->connection_id; 564 } 565 566 memcpy(&newchannel->offermsg, offer, 567 sizeof(struct vmbus_channel_offer_channel)); 568 newchannel->monitor_grp = (u8)offer->monitorid / 32; 569 newchannel->monitor_bit = (u8)offer->monitorid % 32; 570 571 vmbus_process_offer(newchannel); 572 } 573 574 /* 575 * vmbus_onoffer_rescind - Rescind offer handler. 576 * 577 * We queue a work item to process this offer synchronously 578 */ 579 static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) 580 { 581 struct vmbus_channel_rescind_offer *rescind; 582 struct vmbus_channel *channel; 583 unsigned long flags; 584 struct device *dev; 585 586 rescind = (struct vmbus_channel_rescind_offer *)hdr; 587 channel = relid2channel(rescind->child_relid); 588 589 if (channel == NULL) { 590 hv_process_channel_removal(NULL, rescind->child_relid); 591 return; 592 } 593 594 spin_lock_irqsave(&channel->lock, flags); 595 channel->rescind = true; 596 spin_unlock_irqrestore(&channel->lock, flags); 597 598 if (channel->device_obj) { 599 /* 600 * We will have to unregister this device from the 601 * driver core. 602 */ 603 dev = get_device(&channel->device_obj->device); 604 if (dev) { 605 vmbus_device_unregister(channel->device_obj); 606 put_device(dev); 607 } 608 } else { 609 hv_process_channel_removal(channel, 610 channel->offermsg.child_relid); 611 } 612 } 613 614 /* 615 * vmbus_onoffers_delivered - 616 * This is invoked when all offers have been delivered. 617 * 618 * Nothing to do here. 619 */ 620 static void vmbus_onoffers_delivered( 621 struct vmbus_channel_message_header *hdr) 622 { 623 } 624 625 /* 626 * vmbus_onopen_result - Open result handler. 627 * 628 * This is invoked when we received a response to our channel open request. 629 * Find the matching request, copy the response and signal the requesting 630 * thread. 631 */ 632 static void vmbus_onopen_result(struct vmbus_channel_message_header *hdr) 633 { 634 struct vmbus_channel_open_result *result; 635 struct vmbus_channel_msginfo *msginfo; 636 struct vmbus_channel_message_header *requestheader; 637 struct vmbus_channel_open_channel *openmsg; 638 unsigned long flags; 639 640 result = (struct vmbus_channel_open_result *)hdr; 641 642 /* 643 * Find the open msg, copy the result and signal/unblock the wait event 644 */ 645 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 646 647 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, 648 msglistentry) { 649 requestheader = 650 (struct vmbus_channel_message_header *)msginfo->msg; 651 652 if (requestheader->msgtype == CHANNELMSG_OPENCHANNEL) { 653 openmsg = 654 (struct vmbus_channel_open_channel *)msginfo->msg; 655 if (openmsg->child_relid == result->child_relid && 656 openmsg->openid == result->openid) { 657 memcpy(&msginfo->response.open_result, 658 result, 659 sizeof( 660 struct vmbus_channel_open_result)); 661 complete(&msginfo->waitevent); 662 break; 663 } 664 } 665 } 666 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 667 } 668 669 /* 670 * vmbus_ongpadl_created - GPADL created handler. 671 * 672 * This is invoked when we received a response to our gpadl create request. 673 * Find the matching request, copy the response and signal the requesting 674 * thread. 675 */ 676 static void vmbus_ongpadl_created(struct vmbus_channel_message_header *hdr) 677 { 678 struct vmbus_channel_gpadl_created *gpadlcreated; 679 struct vmbus_channel_msginfo *msginfo; 680 struct vmbus_channel_message_header *requestheader; 681 struct vmbus_channel_gpadl_header *gpadlheader; 682 unsigned long flags; 683 684 gpadlcreated = (struct vmbus_channel_gpadl_created *)hdr; 685 686 /* 687 * Find the establish msg, copy the result and signal/unblock the wait 688 * event 689 */ 690 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 691 692 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, 693 msglistentry) { 694 requestheader = 695 (struct vmbus_channel_message_header *)msginfo->msg; 696 697 if (requestheader->msgtype == CHANNELMSG_GPADL_HEADER) { 698 gpadlheader = 699 (struct vmbus_channel_gpadl_header *)requestheader; 700 701 if ((gpadlcreated->child_relid == 702 gpadlheader->child_relid) && 703 (gpadlcreated->gpadl == gpadlheader->gpadl)) { 704 memcpy(&msginfo->response.gpadl_created, 705 gpadlcreated, 706 sizeof( 707 struct vmbus_channel_gpadl_created)); 708 complete(&msginfo->waitevent); 709 break; 710 } 711 } 712 } 713 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 714 } 715 716 /* 717 * vmbus_ongpadl_torndown - GPADL torndown handler. 718 * 719 * This is invoked when we received a response to our gpadl teardown request. 720 * Find the matching request, copy the response and signal the requesting 721 * thread. 722 */ 723 static void vmbus_ongpadl_torndown( 724 struct vmbus_channel_message_header *hdr) 725 { 726 struct vmbus_channel_gpadl_torndown *gpadl_torndown; 727 struct vmbus_channel_msginfo *msginfo; 728 struct vmbus_channel_message_header *requestheader; 729 struct vmbus_channel_gpadl_teardown *gpadl_teardown; 730 unsigned long flags; 731 732 gpadl_torndown = (struct vmbus_channel_gpadl_torndown *)hdr; 733 734 /* 735 * Find the open msg, copy the result and signal/unblock the wait event 736 */ 737 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 738 739 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, 740 msglistentry) { 741 requestheader = 742 (struct vmbus_channel_message_header *)msginfo->msg; 743 744 if (requestheader->msgtype == CHANNELMSG_GPADL_TEARDOWN) { 745 gpadl_teardown = 746 (struct vmbus_channel_gpadl_teardown *)requestheader; 747 748 if (gpadl_torndown->gpadl == gpadl_teardown->gpadl) { 749 memcpy(&msginfo->response.gpadl_torndown, 750 gpadl_torndown, 751 sizeof( 752 struct vmbus_channel_gpadl_torndown)); 753 complete(&msginfo->waitevent); 754 break; 755 } 756 } 757 } 758 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 759 } 760 761 /* 762 * vmbus_onversion_response - Version response handler 763 * 764 * This is invoked when we received a response to our initiate contact request. 765 * Find the matching request, copy the response and signal the requesting 766 * thread. 767 */ 768 static void vmbus_onversion_response( 769 struct vmbus_channel_message_header *hdr) 770 { 771 struct vmbus_channel_msginfo *msginfo; 772 struct vmbus_channel_message_header *requestheader; 773 struct vmbus_channel_version_response *version_response; 774 unsigned long flags; 775 776 version_response = (struct vmbus_channel_version_response *)hdr; 777 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 778 779 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, 780 msglistentry) { 781 requestheader = 782 (struct vmbus_channel_message_header *)msginfo->msg; 783 784 if (requestheader->msgtype == 785 CHANNELMSG_INITIATE_CONTACT) { 786 memcpy(&msginfo->response.version_response, 787 version_response, 788 sizeof(struct vmbus_channel_version_response)); 789 complete(&msginfo->waitevent); 790 } 791 } 792 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 793 } 794 795 /* Channel message dispatch table */ 796 struct vmbus_channel_message_table_entry 797 channel_message_table[CHANNELMSG_COUNT] = { 798 {CHANNELMSG_INVALID, 0, NULL}, 799 {CHANNELMSG_OFFERCHANNEL, 0, vmbus_onoffer}, 800 {CHANNELMSG_RESCIND_CHANNELOFFER, 0, vmbus_onoffer_rescind}, 801 {CHANNELMSG_REQUESTOFFERS, 0, NULL}, 802 {CHANNELMSG_ALLOFFERS_DELIVERED, 1, vmbus_onoffers_delivered}, 803 {CHANNELMSG_OPENCHANNEL, 0, NULL}, 804 {CHANNELMSG_OPENCHANNEL_RESULT, 1, vmbus_onopen_result}, 805 {CHANNELMSG_CLOSECHANNEL, 0, NULL}, 806 {CHANNELMSG_GPADL_HEADER, 0, NULL}, 807 {CHANNELMSG_GPADL_BODY, 0, NULL}, 808 {CHANNELMSG_GPADL_CREATED, 1, vmbus_ongpadl_created}, 809 {CHANNELMSG_GPADL_TEARDOWN, 0, NULL}, 810 {CHANNELMSG_GPADL_TORNDOWN, 1, vmbus_ongpadl_torndown}, 811 {CHANNELMSG_RELID_RELEASED, 0, NULL}, 812 {CHANNELMSG_INITIATE_CONTACT, 0, NULL}, 813 {CHANNELMSG_VERSION_RESPONSE, 1, vmbus_onversion_response}, 814 {CHANNELMSG_UNLOAD, 0, NULL}, 815 {CHANNELMSG_UNLOAD_RESPONSE, 1, vmbus_unload_response}, 816 }; 817 818 /* 819 * vmbus_onmessage - Handler for channel protocol messages. 820 * 821 * This is invoked in the vmbus worker thread context. 822 */ 823 void vmbus_onmessage(void *context) 824 { 825 struct hv_message *msg = context; 826 struct vmbus_channel_message_header *hdr; 827 int size; 828 829 hdr = (struct vmbus_channel_message_header *)msg->u.payload; 830 size = msg->header.payload_size; 831 832 if (hdr->msgtype >= CHANNELMSG_COUNT) { 833 pr_err("Received invalid channel message type %d size %d\n", 834 hdr->msgtype, size); 835 print_hex_dump_bytes("", DUMP_PREFIX_NONE, 836 (unsigned char *)msg->u.payload, size); 837 return; 838 } 839 840 if (channel_message_table[hdr->msgtype].message_handler) 841 channel_message_table[hdr->msgtype].message_handler(hdr); 842 else 843 pr_err("Unhandled channel message type %d\n", hdr->msgtype); 844 } 845 846 /* 847 * vmbus_request_offers - Send a request to get all our pending offers. 848 */ 849 int vmbus_request_offers(void) 850 { 851 struct vmbus_channel_message_header *msg; 852 struct vmbus_channel_msginfo *msginfo; 853 int ret; 854 855 msginfo = kmalloc(sizeof(*msginfo) + 856 sizeof(struct vmbus_channel_message_header), 857 GFP_KERNEL); 858 if (!msginfo) 859 return -ENOMEM; 860 861 msg = (struct vmbus_channel_message_header *)msginfo->msg; 862 863 msg->msgtype = CHANNELMSG_REQUESTOFFERS; 864 865 866 ret = vmbus_post_msg(msg, 867 sizeof(struct vmbus_channel_message_header)); 868 if (ret != 0) { 869 pr_err("Unable to request offers - %d\n", ret); 870 871 goto cleanup; 872 } 873 874 cleanup: 875 kfree(msginfo); 876 877 return ret; 878 } 879 880 /* 881 * Retrieve the (sub) channel on which to send an outgoing request. 882 * When a primary channel has multiple sub-channels, we try to 883 * distribute the load equally amongst all available channels. 884 */ 885 struct vmbus_channel *vmbus_get_outgoing_channel(struct vmbus_channel *primary) 886 { 887 struct list_head *cur, *tmp; 888 int cur_cpu; 889 struct vmbus_channel *cur_channel; 890 struct vmbus_channel *outgoing_channel = primary; 891 int next_channel; 892 int i = 1; 893 894 if (list_empty(&primary->sc_list)) 895 return outgoing_channel; 896 897 next_channel = primary->next_oc++; 898 899 if (next_channel > (primary->num_sc)) { 900 primary->next_oc = 0; 901 return outgoing_channel; 902 } 903 904 cur_cpu = hv_context.vp_index[get_cpu()]; 905 put_cpu(); 906 list_for_each_safe(cur, tmp, &primary->sc_list) { 907 cur_channel = list_entry(cur, struct vmbus_channel, sc_list); 908 if (cur_channel->state != CHANNEL_OPENED_STATE) 909 continue; 910 911 if (cur_channel->target_vp == cur_cpu) 912 return cur_channel; 913 914 if (i == next_channel) 915 return cur_channel; 916 917 i++; 918 } 919 920 return outgoing_channel; 921 } 922 EXPORT_SYMBOL_GPL(vmbus_get_outgoing_channel); 923 924 static void invoke_sc_cb(struct vmbus_channel *primary_channel) 925 { 926 struct list_head *cur, *tmp; 927 struct vmbus_channel *cur_channel; 928 929 if (primary_channel->sc_creation_callback == NULL) 930 return; 931 932 list_for_each_safe(cur, tmp, &primary_channel->sc_list) { 933 cur_channel = list_entry(cur, struct vmbus_channel, sc_list); 934 935 primary_channel->sc_creation_callback(cur_channel); 936 } 937 } 938 939 void vmbus_set_sc_create_callback(struct vmbus_channel *primary_channel, 940 void (*sc_cr_cb)(struct vmbus_channel *new_sc)) 941 { 942 primary_channel->sc_creation_callback = sc_cr_cb; 943 } 944 EXPORT_SYMBOL_GPL(vmbus_set_sc_create_callback); 945 946 bool vmbus_are_subchannels_present(struct vmbus_channel *primary) 947 { 948 bool ret; 949 950 ret = !list_empty(&primary->sc_list); 951 952 if (ret) { 953 /* 954 * Invoke the callback on sub-channel creation. 955 * This will present a uniform interface to the 956 * clients. 957 */ 958 invoke_sc_cb(primary); 959 } 960 961 return ret; 962 } 963 EXPORT_SYMBOL_GPL(vmbus_are_subchannels_present); 964