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 static void vmbus_release_relid(u32 relid) 181 { 182 struct vmbus_channel_relid_released msg; 183 184 memset(&msg, 0, sizeof(struct vmbus_channel_relid_released)); 185 msg.child_relid = relid; 186 msg.header.msgtype = CHANNELMSG_RELID_RELEASED; 187 vmbus_post_msg(&msg, sizeof(struct vmbus_channel_relid_released)); 188 } 189 190 void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid) 191 { 192 unsigned long flags; 193 struct vmbus_channel *primary_channel; 194 195 vmbus_release_relid(relid); 196 197 BUG_ON(!channel->rescind); 198 199 if (channel->target_cpu != get_cpu()) { 200 put_cpu(); 201 smp_call_function_single(channel->target_cpu, 202 percpu_channel_deq, channel, true); 203 } else { 204 percpu_channel_deq(channel); 205 put_cpu(); 206 } 207 208 if (channel->primary_channel == NULL) { 209 spin_lock_irqsave(&vmbus_connection.channel_lock, flags); 210 list_del(&channel->listentry); 211 spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags); 212 213 primary_channel = channel; 214 } else { 215 primary_channel = channel->primary_channel; 216 spin_lock_irqsave(&primary_channel->lock, flags); 217 list_del(&channel->sc_list); 218 primary_channel->num_sc--; 219 spin_unlock_irqrestore(&primary_channel->lock, flags); 220 } 221 222 /* 223 * We need to free the bit for init_vp_index() to work in the case 224 * of sub-channel, when we reload drivers like hv_netvsc. 225 */ 226 cpumask_clear_cpu(channel->target_cpu, 227 &primary_channel->alloced_cpus_in_node); 228 229 free_channel(channel); 230 } 231 232 void vmbus_free_channels(void) 233 { 234 struct vmbus_channel *channel, *tmp; 235 236 list_for_each_entry_safe(channel, tmp, &vmbus_connection.chn_list, 237 listentry) { 238 /* hv_process_channel_removal() needs this */ 239 channel->rescind = true; 240 241 vmbus_device_unregister(channel->device_obj); 242 } 243 } 244 245 /* 246 * vmbus_process_offer - Process the offer by creating a channel/device 247 * associated with this offer 248 */ 249 static void vmbus_process_offer(struct vmbus_channel *newchannel) 250 { 251 struct vmbus_channel *channel; 252 bool fnew = true; 253 unsigned long flags; 254 255 /* Make sure this is a new offer */ 256 spin_lock_irqsave(&vmbus_connection.channel_lock, flags); 257 258 list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) { 259 if (!uuid_le_cmp(channel->offermsg.offer.if_type, 260 newchannel->offermsg.offer.if_type) && 261 !uuid_le_cmp(channel->offermsg.offer.if_instance, 262 newchannel->offermsg.offer.if_instance)) { 263 fnew = false; 264 break; 265 } 266 } 267 268 if (fnew) 269 list_add_tail(&newchannel->listentry, 270 &vmbus_connection.chn_list); 271 272 spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags); 273 274 if (!fnew) { 275 /* 276 * Check to see if this is a sub-channel. 277 */ 278 if (newchannel->offermsg.offer.sub_channel_index != 0) { 279 /* 280 * Process the sub-channel. 281 */ 282 newchannel->primary_channel = channel; 283 spin_lock_irqsave(&channel->lock, flags); 284 list_add_tail(&newchannel->sc_list, &channel->sc_list); 285 channel->num_sc++; 286 spin_unlock_irqrestore(&channel->lock, flags); 287 } else 288 goto err_free_chan; 289 } 290 291 init_vp_index(newchannel, &newchannel->offermsg.offer.if_type); 292 293 if (newchannel->target_cpu != get_cpu()) { 294 put_cpu(); 295 smp_call_function_single(newchannel->target_cpu, 296 percpu_channel_enq, 297 newchannel, true); 298 } else { 299 percpu_channel_enq(newchannel); 300 put_cpu(); 301 } 302 303 /* 304 * This state is used to indicate a successful open 305 * so that when we do close the channel normally, we 306 * can cleanup properly 307 */ 308 newchannel->state = CHANNEL_OPEN_STATE; 309 310 if (!fnew) { 311 if (channel->sc_creation_callback != NULL) 312 channel->sc_creation_callback(newchannel); 313 return; 314 } 315 316 /* 317 * Start the process of binding this offer to the driver 318 * We need to set the DeviceObject field before calling 319 * vmbus_child_dev_add() 320 */ 321 newchannel->device_obj = vmbus_device_create( 322 &newchannel->offermsg.offer.if_type, 323 &newchannel->offermsg.offer.if_instance, 324 newchannel); 325 if (!newchannel->device_obj) 326 goto err_deq_chan; 327 328 /* 329 * Add the new device to the bus. This will kick off device-driver 330 * binding which eventually invokes the device driver's AddDevice() 331 * method. 332 */ 333 if (vmbus_device_register(newchannel->device_obj) != 0) { 334 pr_err("unable to add child device object (relid %d)\n", 335 newchannel->offermsg.child_relid); 336 kfree(newchannel->device_obj); 337 goto err_deq_chan; 338 } 339 return; 340 341 err_deq_chan: 342 vmbus_release_relid(newchannel->offermsg.child_relid); 343 344 spin_lock_irqsave(&vmbus_connection.channel_lock, flags); 345 list_del(&newchannel->listentry); 346 spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags); 347 348 if (newchannel->target_cpu != get_cpu()) { 349 put_cpu(); 350 smp_call_function_single(newchannel->target_cpu, 351 percpu_channel_deq, newchannel, true); 352 } else { 353 percpu_channel_deq(newchannel); 354 put_cpu(); 355 } 356 357 err_free_chan: 358 free_channel(newchannel); 359 } 360 361 enum { 362 IDE = 0, 363 SCSI, 364 NIC, 365 ND_NIC, 366 PCIE, 367 MAX_PERF_CHN, 368 }; 369 370 /* 371 * This is an array of device_ids (device types) that are performance critical. 372 * We attempt to distribute the interrupt load for these devices across 373 * all available CPUs. 374 */ 375 static const struct hv_vmbus_device_id hp_devs[] = { 376 /* IDE */ 377 { HV_IDE_GUID, }, 378 /* Storage - SCSI */ 379 { HV_SCSI_GUID, }, 380 /* Network */ 381 { HV_NIC_GUID, }, 382 /* NetworkDirect Guest RDMA */ 383 { HV_ND_GUID, }, 384 /* PCI Express Pass Through */ 385 { HV_PCIE_GUID, }, 386 }; 387 388 389 /* 390 * We use this state to statically distribute the channel interrupt load. 391 */ 392 static int next_numa_node_id; 393 394 /* 395 * Starting with Win8, we can statically distribute the incoming 396 * channel interrupt load by binding a channel to VCPU. 397 * We do this in a hierarchical fashion: 398 * First distribute the primary channels across available NUMA nodes 399 * and then distribute the subchannels amongst the CPUs in the NUMA 400 * node assigned to the primary channel. 401 * 402 * For pre-win8 hosts or non-performance critical channels we assign the 403 * first CPU in the first NUMA node. 404 */ 405 static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_guid) 406 { 407 u32 cur_cpu; 408 int i; 409 bool perf_chn = false; 410 struct vmbus_channel *primary = channel->primary_channel; 411 int next_node; 412 struct cpumask available_mask; 413 struct cpumask *alloced_mask; 414 415 for (i = IDE; i < MAX_PERF_CHN; i++) { 416 if (!uuid_le_cmp(*type_guid, hp_devs[i].guid)) { 417 perf_chn = true; 418 break; 419 } 420 } 421 if ((vmbus_proto_version == VERSION_WS2008) || 422 (vmbus_proto_version == VERSION_WIN7) || (!perf_chn)) { 423 /* 424 * Prior to win8, all channel interrupts are 425 * delivered on cpu 0. 426 * Also if the channel is not a performance critical 427 * channel, bind it to cpu 0. 428 */ 429 channel->numa_node = 0; 430 channel->target_cpu = 0; 431 channel->target_vp = hv_context.vp_index[0]; 432 return; 433 } 434 435 /* 436 * We distribute primary channels evenly across all the available 437 * NUMA nodes and within the assigned NUMA node we will assign the 438 * first available CPU to the primary channel. 439 * The sub-channels will be assigned to the CPUs available in the 440 * NUMA node evenly. 441 */ 442 if (!primary) { 443 while (true) { 444 next_node = next_numa_node_id++; 445 if (next_node == nr_node_ids) 446 next_node = next_numa_node_id = 0; 447 if (cpumask_empty(cpumask_of_node(next_node))) 448 continue; 449 break; 450 } 451 channel->numa_node = next_node; 452 primary = channel; 453 } 454 alloced_mask = &hv_context.hv_numa_map[primary->numa_node]; 455 456 if (cpumask_weight(alloced_mask) == 457 cpumask_weight(cpumask_of_node(primary->numa_node))) { 458 /* 459 * We have cycled through all the CPUs in the node; 460 * reset the alloced map. 461 */ 462 cpumask_clear(alloced_mask); 463 } 464 465 cpumask_xor(&available_mask, alloced_mask, 466 cpumask_of_node(primary->numa_node)); 467 468 cur_cpu = -1; 469 while (true) { 470 cur_cpu = cpumask_next(cur_cpu, &available_mask); 471 if (cur_cpu >= nr_cpu_ids) { 472 cur_cpu = -1; 473 cpumask_copy(&available_mask, 474 cpumask_of_node(primary->numa_node)); 475 continue; 476 } 477 478 /* 479 * NOTE: in the case of sub-channel, we clear the sub-channel 480 * related bit(s) in primary->alloced_cpus_in_node in 481 * hv_process_channel_removal(), so when we reload drivers 482 * like hv_netvsc in SMP guest, here we're able to re-allocate 483 * bit from primary->alloced_cpus_in_node. 484 */ 485 if (!cpumask_test_cpu(cur_cpu, 486 &primary->alloced_cpus_in_node)) { 487 cpumask_set_cpu(cur_cpu, 488 &primary->alloced_cpus_in_node); 489 cpumask_set_cpu(cur_cpu, alloced_mask); 490 break; 491 } 492 } 493 494 channel->target_cpu = cur_cpu; 495 channel->target_vp = hv_context.vp_index[cur_cpu]; 496 } 497 498 /* 499 * vmbus_unload_response - Handler for the unload response. 500 */ 501 static void vmbus_unload_response(struct vmbus_channel_message_header *hdr) 502 { 503 /* 504 * This is a global event; just wakeup the waiting thread. 505 * Once we successfully unload, we can cleanup the monitor state. 506 */ 507 complete(&vmbus_connection.unload_event); 508 } 509 510 void vmbus_initiate_unload(void) 511 { 512 struct vmbus_channel_message_header hdr; 513 514 /* Pre-Win2012R2 hosts don't support reconnect */ 515 if (vmbus_proto_version < VERSION_WIN8_1) 516 return; 517 518 init_completion(&vmbus_connection.unload_event); 519 memset(&hdr, 0, sizeof(struct vmbus_channel_message_header)); 520 hdr.msgtype = CHANNELMSG_UNLOAD; 521 vmbus_post_msg(&hdr, sizeof(struct vmbus_channel_message_header)); 522 523 wait_for_completion(&vmbus_connection.unload_event); 524 } 525 526 /* 527 * vmbus_onoffer - Handler for channel offers from vmbus in parent partition. 528 * 529 */ 530 static void vmbus_onoffer(struct vmbus_channel_message_header *hdr) 531 { 532 struct vmbus_channel_offer_channel *offer; 533 struct vmbus_channel *newchannel; 534 535 offer = (struct vmbus_channel_offer_channel *)hdr; 536 537 /* Allocate the channel object and save this offer. */ 538 newchannel = alloc_channel(); 539 if (!newchannel) { 540 pr_err("Unable to allocate channel object\n"); 541 return; 542 } 543 544 /* 545 * By default we setup state to enable batched 546 * reading. A specific service can choose to 547 * disable this prior to opening the channel. 548 */ 549 newchannel->batched_reading = true; 550 551 /* 552 * Setup state for signalling the host. 553 */ 554 newchannel->sig_event = (struct hv_input_signal_event *) 555 (ALIGN((unsigned long) 556 &newchannel->sig_buf, 557 HV_HYPERCALL_PARAM_ALIGN)); 558 559 newchannel->sig_event->connectionid.asu32 = 0; 560 newchannel->sig_event->connectionid.u.id = VMBUS_EVENT_CONNECTION_ID; 561 newchannel->sig_event->flag_number = 0; 562 newchannel->sig_event->rsvdz = 0; 563 564 if (vmbus_proto_version != VERSION_WS2008) { 565 newchannel->is_dedicated_interrupt = 566 (offer->is_dedicated_interrupt != 0); 567 newchannel->sig_event->connectionid.u.id = 568 offer->connection_id; 569 } 570 571 memcpy(&newchannel->offermsg, offer, 572 sizeof(struct vmbus_channel_offer_channel)); 573 newchannel->monitor_grp = (u8)offer->monitorid / 32; 574 newchannel->monitor_bit = (u8)offer->monitorid % 32; 575 576 vmbus_process_offer(newchannel); 577 } 578 579 /* 580 * vmbus_onoffer_rescind - Rescind offer handler. 581 * 582 * We queue a work item to process this offer synchronously 583 */ 584 static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) 585 { 586 struct vmbus_channel_rescind_offer *rescind; 587 struct vmbus_channel *channel; 588 unsigned long flags; 589 struct device *dev; 590 591 rescind = (struct vmbus_channel_rescind_offer *)hdr; 592 channel = relid2channel(rescind->child_relid); 593 594 if (channel == NULL) { 595 /* 596 * This is very impossible, because in 597 * vmbus_process_offer(), we have already invoked 598 * vmbus_release_relid() on error. 599 */ 600 return; 601 } 602 603 spin_lock_irqsave(&channel->lock, flags); 604 channel->rescind = true; 605 spin_unlock_irqrestore(&channel->lock, flags); 606 607 if (channel->device_obj) { 608 /* 609 * We will have to unregister this device from the 610 * driver core. 611 */ 612 dev = get_device(&channel->device_obj->device); 613 if (dev) { 614 vmbus_device_unregister(channel->device_obj); 615 put_device(dev); 616 } 617 } else { 618 hv_process_channel_removal(channel, 619 channel->offermsg.child_relid); 620 } 621 } 622 623 /* 624 * vmbus_onoffers_delivered - 625 * This is invoked when all offers have been delivered. 626 * 627 * Nothing to do here. 628 */ 629 static void vmbus_onoffers_delivered( 630 struct vmbus_channel_message_header *hdr) 631 { 632 } 633 634 /* 635 * vmbus_onopen_result - Open result handler. 636 * 637 * This is invoked when we received a response to our channel open request. 638 * Find the matching request, copy the response and signal the requesting 639 * thread. 640 */ 641 static void vmbus_onopen_result(struct vmbus_channel_message_header *hdr) 642 { 643 struct vmbus_channel_open_result *result; 644 struct vmbus_channel_msginfo *msginfo; 645 struct vmbus_channel_message_header *requestheader; 646 struct vmbus_channel_open_channel *openmsg; 647 unsigned long flags; 648 649 result = (struct vmbus_channel_open_result *)hdr; 650 651 /* 652 * Find the open msg, copy the result and signal/unblock the wait event 653 */ 654 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 655 656 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, 657 msglistentry) { 658 requestheader = 659 (struct vmbus_channel_message_header *)msginfo->msg; 660 661 if (requestheader->msgtype == CHANNELMSG_OPENCHANNEL) { 662 openmsg = 663 (struct vmbus_channel_open_channel *)msginfo->msg; 664 if (openmsg->child_relid == result->child_relid && 665 openmsg->openid == result->openid) { 666 memcpy(&msginfo->response.open_result, 667 result, 668 sizeof( 669 struct vmbus_channel_open_result)); 670 complete(&msginfo->waitevent); 671 break; 672 } 673 } 674 } 675 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 676 } 677 678 /* 679 * vmbus_ongpadl_created - GPADL created handler. 680 * 681 * This is invoked when we received a response to our gpadl create request. 682 * Find the matching request, copy the response and signal the requesting 683 * thread. 684 */ 685 static void vmbus_ongpadl_created(struct vmbus_channel_message_header *hdr) 686 { 687 struct vmbus_channel_gpadl_created *gpadlcreated; 688 struct vmbus_channel_msginfo *msginfo; 689 struct vmbus_channel_message_header *requestheader; 690 struct vmbus_channel_gpadl_header *gpadlheader; 691 unsigned long flags; 692 693 gpadlcreated = (struct vmbus_channel_gpadl_created *)hdr; 694 695 /* 696 * Find the establish msg, copy the result and signal/unblock the wait 697 * event 698 */ 699 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 700 701 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, 702 msglistentry) { 703 requestheader = 704 (struct vmbus_channel_message_header *)msginfo->msg; 705 706 if (requestheader->msgtype == CHANNELMSG_GPADL_HEADER) { 707 gpadlheader = 708 (struct vmbus_channel_gpadl_header *)requestheader; 709 710 if ((gpadlcreated->child_relid == 711 gpadlheader->child_relid) && 712 (gpadlcreated->gpadl == gpadlheader->gpadl)) { 713 memcpy(&msginfo->response.gpadl_created, 714 gpadlcreated, 715 sizeof( 716 struct vmbus_channel_gpadl_created)); 717 complete(&msginfo->waitevent); 718 break; 719 } 720 } 721 } 722 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 723 } 724 725 /* 726 * vmbus_ongpadl_torndown - GPADL torndown handler. 727 * 728 * This is invoked when we received a response to our gpadl teardown request. 729 * Find the matching request, copy the response and signal the requesting 730 * thread. 731 */ 732 static void vmbus_ongpadl_torndown( 733 struct vmbus_channel_message_header *hdr) 734 { 735 struct vmbus_channel_gpadl_torndown *gpadl_torndown; 736 struct vmbus_channel_msginfo *msginfo; 737 struct vmbus_channel_message_header *requestheader; 738 struct vmbus_channel_gpadl_teardown *gpadl_teardown; 739 unsigned long flags; 740 741 gpadl_torndown = (struct vmbus_channel_gpadl_torndown *)hdr; 742 743 /* 744 * Find the open msg, copy the result and signal/unblock the wait event 745 */ 746 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 747 748 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, 749 msglistentry) { 750 requestheader = 751 (struct vmbus_channel_message_header *)msginfo->msg; 752 753 if (requestheader->msgtype == CHANNELMSG_GPADL_TEARDOWN) { 754 gpadl_teardown = 755 (struct vmbus_channel_gpadl_teardown *)requestheader; 756 757 if (gpadl_torndown->gpadl == gpadl_teardown->gpadl) { 758 memcpy(&msginfo->response.gpadl_torndown, 759 gpadl_torndown, 760 sizeof( 761 struct vmbus_channel_gpadl_torndown)); 762 complete(&msginfo->waitevent); 763 break; 764 } 765 } 766 } 767 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 768 } 769 770 /* 771 * vmbus_onversion_response - Version response handler 772 * 773 * This is invoked when we received a response to our initiate contact request. 774 * Find the matching request, copy the response and signal the requesting 775 * thread. 776 */ 777 static void vmbus_onversion_response( 778 struct vmbus_channel_message_header *hdr) 779 { 780 struct vmbus_channel_msginfo *msginfo; 781 struct vmbus_channel_message_header *requestheader; 782 struct vmbus_channel_version_response *version_response; 783 unsigned long flags; 784 785 version_response = (struct vmbus_channel_version_response *)hdr; 786 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 787 788 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, 789 msglistentry) { 790 requestheader = 791 (struct vmbus_channel_message_header *)msginfo->msg; 792 793 if (requestheader->msgtype == 794 CHANNELMSG_INITIATE_CONTACT) { 795 memcpy(&msginfo->response.version_response, 796 version_response, 797 sizeof(struct vmbus_channel_version_response)); 798 complete(&msginfo->waitevent); 799 } 800 } 801 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 802 } 803 804 /* Channel message dispatch table */ 805 struct vmbus_channel_message_table_entry 806 channel_message_table[CHANNELMSG_COUNT] = { 807 {CHANNELMSG_INVALID, 0, NULL}, 808 {CHANNELMSG_OFFERCHANNEL, 0, vmbus_onoffer}, 809 {CHANNELMSG_RESCIND_CHANNELOFFER, 0, vmbus_onoffer_rescind}, 810 {CHANNELMSG_REQUESTOFFERS, 0, NULL}, 811 {CHANNELMSG_ALLOFFERS_DELIVERED, 1, vmbus_onoffers_delivered}, 812 {CHANNELMSG_OPENCHANNEL, 0, NULL}, 813 {CHANNELMSG_OPENCHANNEL_RESULT, 1, vmbus_onopen_result}, 814 {CHANNELMSG_CLOSECHANNEL, 0, NULL}, 815 {CHANNELMSG_GPADL_HEADER, 0, NULL}, 816 {CHANNELMSG_GPADL_BODY, 0, NULL}, 817 {CHANNELMSG_GPADL_CREATED, 1, vmbus_ongpadl_created}, 818 {CHANNELMSG_GPADL_TEARDOWN, 0, NULL}, 819 {CHANNELMSG_GPADL_TORNDOWN, 1, vmbus_ongpadl_torndown}, 820 {CHANNELMSG_RELID_RELEASED, 0, NULL}, 821 {CHANNELMSG_INITIATE_CONTACT, 0, NULL}, 822 {CHANNELMSG_VERSION_RESPONSE, 1, vmbus_onversion_response}, 823 {CHANNELMSG_UNLOAD, 0, NULL}, 824 {CHANNELMSG_UNLOAD_RESPONSE, 1, vmbus_unload_response}, 825 }; 826 827 /* 828 * vmbus_onmessage - Handler for channel protocol messages. 829 * 830 * This is invoked in the vmbus worker thread context. 831 */ 832 void vmbus_onmessage(void *context) 833 { 834 struct hv_message *msg = context; 835 struct vmbus_channel_message_header *hdr; 836 int size; 837 838 hdr = (struct vmbus_channel_message_header *)msg->u.payload; 839 size = msg->header.payload_size; 840 841 if (hdr->msgtype >= CHANNELMSG_COUNT) { 842 pr_err("Received invalid channel message type %d size %d\n", 843 hdr->msgtype, size); 844 print_hex_dump_bytes("", DUMP_PREFIX_NONE, 845 (unsigned char *)msg->u.payload, size); 846 return; 847 } 848 849 if (channel_message_table[hdr->msgtype].message_handler) 850 channel_message_table[hdr->msgtype].message_handler(hdr); 851 else 852 pr_err("Unhandled channel message type %d\n", hdr->msgtype); 853 } 854 855 /* 856 * vmbus_request_offers - Send a request to get all our pending offers. 857 */ 858 int vmbus_request_offers(void) 859 { 860 struct vmbus_channel_message_header *msg; 861 struct vmbus_channel_msginfo *msginfo; 862 int ret; 863 864 msginfo = kmalloc(sizeof(*msginfo) + 865 sizeof(struct vmbus_channel_message_header), 866 GFP_KERNEL); 867 if (!msginfo) 868 return -ENOMEM; 869 870 msg = (struct vmbus_channel_message_header *)msginfo->msg; 871 872 msg->msgtype = CHANNELMSG_REQUESTOFFERS; 873 874 875 ret = vmbus_post_msg(msg, 876 sizeof(struct vmbus_channel_message_header)); 877 if (ret != 0) { 878 pr_err("Unable to request offers - %d\n", ret); 879 880 goto cleanup; 881 } 882 883 cleanup: 884 kfree(msginfo); 885 886 return ret; 887 } 888 889 /* 890 * Retrieve the (sub) channel on which to send an outgoing request. 891 * When a primary channel has multiple sub-channels, we try to 892 * distribute the load equally amongst all available channels. 893 */ 894 struct vmbus_channel *vmbus_get_outgoing_channel(struct vmbus_channel *primary) 895 { 896 struct list_head *cur, *tmp; 897 int cur_cpu; 898 struct vmbus_channel *cur_channel; 899 struct vmbus_channel *outgoing_channel = primary; 900 int next_channel; 901 int i = 1; 902 903 if (list_empty(&primary->sc_list)) 904 return outgoing_channel; 905 906 next_channel = primary->next_oc++; 907 908 if (next_channel > (primary->num_sc)) { 909 primary->next_oc = 0; 910 return outgoing_channel; 911 } 912 913 cur_cpu = hv_context.vp_index[get_cpu()]; 914 put_cpu(); 915 list_for_each_safe(cur, tmp, &primary->sc_list) { 916 cur_channel = list_entry(cur, struct vmbus_channel, sc_list); 917 if (cur_channel->state != CHANNEL_OPENED_STATE) 918 continue; 919 920 if (cur_channel->target_vp == cur_cpu) 921 return cur_channel; 922 923 if (i == next_channel) 924 return cur_channel; 925 926 i++; 927 } 928 929 return outgoing_channel; 930 } 931 EXPORT_SYMBOL_GPL(vmbus_get_outgoing_channel); 932 933 static void invoke_sc_cb(struct vmbus_channel *primary_channel) 934 { 935 struct list_head *cur, *tmp; 936 struct vmbus_channel *cur_channel; 937 938 if (primary_channel->sc_creation_callback == NULL) 939 return; 940 941 list_for_each_safe(cur, tmp, &primary_channel->sc_list) { 942 cur_channel = list_entry(cur, struct vmbus_channel, sc_list); 943 944 primary_channel->sc_creation_callback(cur_channel); 945 } 946 } 947 948 void vmbus_set_sc_create_callback(struct vmbus_channel *primary_channel, 949 void (*sc_cr_cb)(struct vmbus_channel *new_sc)) 950 { 951 primary_channel->sc_creation_callback = sc_cr_cb; 952 } 953 EXPORT_SYMBOL_GPL(vmbus_set_sc_create_callback); 954 955 bool vmbus_are_subchannels_present(struct vmbus_channel *primary) 956 { 957 bool ret; 958 959 ret = !list_empty(&primary->sc_list); 960 961 if (ret) { 962 /* 963 * Invoke the callback on sub-channel creation. 964 * This will present a uniform interface to the 965 * clients. 966 */ 967 invoke_sc_cb(primary); 968 } 969 970 return ret; 971 } 972 EXPORT_SYMBOL_GPL(vmbus_are_subchannels_present); 973