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/delay.h> 32 #include <linux/hyperv.h> 33 34 #include "hyperv_vmbus.h" 35 36 static void init_vp_index(struct vmbus_channel *channel, u16 dev_type); 37 38 static const struct vmbus_device vmbus_devs[] = { 39 /* IDE */ 40 { .dev_type = HV_IDE, 41 HV_IDE_GUID, 42 .perf_device = true, 43 }, 44 45 /* SCSI */ 46 { .dev_type = HV_SCSI, 47 HV_SCSI_GUID, 48 .perf_device = true, 49 }, 50 51 /* Fibre Channel */ 52 { .dev_type = HV_FC, 53 HV_SYNTHFC_GUID, 54 .perf_device = true, 55 }, 56 57 /* Synthetic NIC */ 58 { .dev_type = HV_NIC, 59 HV_NIC_GUID, 60 .perf_device = true, 61 }, 62 63 /* Network Direct */ 64 { .dev_type = HV_ND, 65 HV_ND_GUID, 66 .perf_device = true, 67 }, 68 69 /* PCIE */ 70 { .dev_type = HV_PCIE, 71 HV_PCIE_GUID, 72 .perf_device = true, 73 }, 74 75 /* Synthetic Frame Buffer */ 76 { .dev_type = HV_FB, 77 HV_SYNTHVID_GUID, 78 .perf_device = false, 79 }, 80 81 /* Synthetic Keyboard */ 82 { .dev_type = HV_KBD, 83 HV_KBD_GUID, 84 .perf_device = false, 85 }, 86 87 /* Synthetic MOUSE */ 88 { .dev_type = HV_MOUSE, 89 HV_MOUSE_GUID, 90 .perf_device = false, 91 }, 92 93 /* KVP */ 94 { .dev_type = HV_KVP, 95 HV_KVP_GUID, 96 .perf_device = false, 97 }, 98 99 /* Time Synch */ 100 { .dev_type = HV_TS, 101 HV_TS_GUID, 102 .perf_device = false, 103 }, 104 105 /* Heartbeat */ 106 { .dev_type = HV_HB, 107 HV_HEART_BEAT_GUID, 108 .perf_device = false, 109 }, 110 111 /* Shutdown */ 112 { .dev_type = HV_SHUTDOWN, 113 HV_SHUTDOWN_GUID, 114 .perf_device = false, 115 }, 116 117 /* File copy */ 118 { .dev_type = HV_FCOPY, 119 HV_FCOPY_GUID, 120 .perf_device = false, 121 }, 122 123 /* Backup */ 124 { .dev_type = HV_BACKUP, 125 HV_VSS_GUID, 126 .perf_device = false, 127 }, 128 129 /* Dynamic Memory */ 130 { .dev_type = HV_DM, 131 HV_DM_GUID, 132 .perf_device = false, 133 }, 134 135 /* Unknown GUID */ 136 { .dev_type = HV_UNKOWN, 137 .perf_device = false, 138 }, 139 }; 140 141 static u16 hv_get_dev_type(const uuid_le *guid) 142 { 143 u16 i; 144 145 for (i = HV_IDE; i < HV_UNKOWN; i++) { 146 if (!uuid_le_cmp(*guid, vmbus_devs[i].guid)) 147 return i; 148 } 149 pr_info("Unknown GUID: %pUl\n", guid); 150 return i; 151 } 152 153 /** 154 * vmbus_prep_negotiate_resp() - Create default response for Hyper-V Negotiate message 155 * @icmsghdrp: Pointer to msg header structure 156 * @icmsg_negotiate: Pointer to negotiate message structure 157 * @buf: Raw buffer channel data 158 * 159 * @icmsghdrp is of type &struct icmsg_hdr. 160 * @negop is of type &struct icmsg_negotiate. 161 * Set up and fill in default negotiate response message. 162 * 163 * The fw_version specifies the framework version that 164 * we can support and srv_version specifies the service 165 * version we can support. 166 * 167 * Mainly used by Hyper-V drivers. 168 */ 169 bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp, 170 struct icmsg_negotiate *negop, u8 *buf, 171 int fw_version, int srv_version) 172 { 173 int icframe_major, icframe_minor; 174 int icmsg_major, icmsg_minor; 175 int fw_major, fw_minor; 176 int srv_major, srv_minor; 177 int i; 178 bool found_match = false; 179 180 icmsghdrp->icmsgsize = 0x10; 181 fw_major = (fw_version >> 16); 182 fw_minor = (fw_version & 0xFFFF); 183 184 srv_major = (srv_version >> 16); 185 srv_minor = (srv_version & 0xFFFF); 186 187 negop = (struct icmsg_negotiate *)&buf[ 188 sizeof(struct vmbuspipe_hdr) + 189 sizeof(struct icmsg_hdr)]; 190 191 icframe_major = negop->icframe_vercnt; 192 icframe_minor = 0; 193 194 icmsg_major = negop->icmsg_vercnt; 195 icmsg_minor = 0; 196 197 /* 198 * Select the framework version number we will 199 * support. 200 */ 201 202 for (i = 0; i < negop->icframe_vercnt; i++) { 203 if ((negop->icversion_data[i].major == fw_major) && 204 (negop->icversion_data[i].minor == fw_minor)) { 205 icframe_major = negop->icversion_data[i].major; 206 icframe_minor = negop->icversion_data[i].minor; 207 found_match = true; 208 } 209 } 210 211 if (!found_match) 212 goto fw_error; 213 214 found_match = false; 215 216 for (i = negop->icframe_vercnt; 217 (i < negop->icframe_vercnt + negop->icmsg_vercnt); i++) { 218 if ((negop->icversion_data[i].major == srv_major) && 219 (negop->icversion_data[i].minor == srv_minor)) { 220 icmsg_major = negop->icversion_data[i].major; 221 icmsg_minor = negop->icversion_data[i].minor; 222 found_match = true; 223 } 224 } 225 226 /* 227 * Respond with the framework and service 228 * version numbers we can support. 229 */ 230 231 fw_error: 232 if (!found_match) { 233 negop->icframe_vercnt = 0; 234 negop->icmsg_vercnt = 0; 235 } else { 236 negop->icframe_vercnt = 1; 237 negop->icmsg_vercnt = 1; 238 } 239 240 negop->icversion_data[0].major = icframe_major; 241 negop->icversion_data[0].minor = icframe_minor; 242 negop->icversion_data[1].major = icmsg_major; 243 negop->icversion_data[1].minor = icmsg_minor; 244 return found_match; 245 } 246 247 EXPORT_SYMBOL_GPL(vmbus_prep_negotiate_resp); 248 249 /* 250 * alloc_channel - Allocate and initialize a vmbus channel object 251 */ 252 static struct vmbus_channel *alloc_channel(void) 253 { 254 static atomic_t chan_num = ATOMIC_INIT(0); 255 struct vmbus_channel *channel; 256 257 channel = kzalloc(sizeof(*channel), GFP_ATOMIC); 258 if (!channel) 259 return NULL; 260 261 channel->id = atomic_inc_return(&chan_num); 262 spin_lock_init(&channel->inbound_lock); 263 spin_lock_init(&channel->lock); 264 265 INIT_LIST_HEAD(&channel->sc_list); 266 INIT_LIST_HEAD(&channel->percpu_list); 267 268 return channel; 269 } 270 271 /* 272 * free_channel - Release the resources used by the vmbus channel object 273 */ 274 static void free_channel(struct vmbus_channel *channel) 275 { 276 kfree(channel); 277 } 278 279 static void percpu_channel_enq(void *arg) 280 { 281 struct vmbus_channel *channel = arg; 282 int cpu = smp_processor_id(); 283 284 list_add_tail(&channel->percpu_list, &hv_context.percpu_list[cpu]); 285 } 286 287 static void percpu_channel_deq(void *arg) 288 { 289 struct vmbus_channel *channel = arg; 290 291 list_del(&channel->percpu_list); 292 } 293 294 295 static void vmbus_release_relid(u32 relid) 296 { 297 struct vmbus_channel_relid_released msg; 298 299 memset(&msg, 0, sizeof(struct vmbus_channel_relid_released)); 300 msg.child_relid = relid; 301 msg.header.msgtype = CHANNELMSG_RELID_RELEASED; 302 vmbus_post_msg(&msg, sizeof(struct vmbus_channel_relid_released)); 303 } 304 305 void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid) 306 { 307 unsigned long flags; 308 struct vmbus_channel *primary_channel; 309 310 vmbus_release_relid(relid); 311 312 BUG_ON(!channel->rescind); 313 314 if (channel->target_cpu != get_cpu()) { 315 put_cpu(); 316 smp_call_function_single(channel->target_cpu, 317 percpu_channel_deq, channel, true); 318 } else { 319 percpu_channel_deq(channel); 320 put_cpu(); 321 } 322 323 if (channel->primary_channel == NULL) { 324 mutex_lock(&vmbus_connection.channel_mutex); 325 list_del(&channel->listentry); 326 mutex_unlock(&vmbus_connection.channel_mutex); 327 328 primary_channel = channel; 329 } else { 330 primary_channel = channel->primary_channel; 331 spin_lock_irqsave(&primary_channel->lock, flags); 332 list_del(&channel->sc_list); 333 primary_channel->num_sc--; 334 spin_unlock_irqrestore(&primary_channel->lock, flags); 335 } 336 337 /* 338 * We need to free the bit for init_vp_index() to work in the case 339 * of sub-channel, when we reload drivers like hv_netvsc. 340 */ 341 cpumask_clear_cpu(channel->target_cpu, 342 &primary_channel->alloced_cpus_in_node); 343 344 free_channel(channel); 345 } 346 347 void vmbus_free_channels(void) 348 { 349 struct vmbus_channel *channel, *tmp; 350 351 list_for_each_entry_safe(channel, tmp, &vmbus_connection.chn_list, 352 listentry) { 353 /* hv_process_channel_removal() needs this */ 354 channel->rescind = true; 355 356 vmbus_device_unregister(channel->device_obj); 357 } 358 } 359 360 /* 361 * vmbus_process_offer - Process the offer by creating a channel/device 362 * associated with this offer 363 */ 364 static void vmbus_process_offer(struct vmbus_channel *newchannel) 365 { 366 struct vmbus_channel *channel; 367 bool fnew = true; 368 unsigned long flags; 369 u16 dev_type; 370 371 /* Make sure this is a new offer */ 372 mutex_lock(&vmbus_connection.channel_mutex); 373 374 list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) { 375 if (!uuid_le_cmp(channel->offermsg.offer.if_type, 376 newchannel->offermsg.offer.if_type) && 377 !uuid_le_cmp(channel->offermsg.offer.if_instance, 378 newchannel->offermsg.offer.if_instance)) { 379 fnew = false; 380 break; 381 } 382 } 383 384 if (fnew) 385 list_add_tail(&newchannel->listentry, 386 &vmbus_connection.chn_list); 387 388 mutex_unlock(&vmbus_connection.channel_mutex); 389 390 if (!fnew) { 391 /* 392 * Check to see if this is a sub-channel. 393 */ 394 if (newchannel->offermsg.offer.sub_channel_index != 0) { 395 /* 396 * Process the sub-channel. 397 */ 398 newchannel->primary_channel = channel; 399 spin_lock_irqsave(&channel->lock, flags); 400 list_add_tail(&newchannel->sc_list, &channel->sc_list); 401 channel->num_sc++; 402 spin_unlock_irqrestore(&channel->lock, flags); 403 } else 404 goto err_free_chan; 405 } 406 407 dev_type = hv_get_dev_type(&newchannel->offermsg.offer.if_type); 408 409 init_vp_index(newchannel, dev_type); 410 411 if (newchannel->target_cpu != get_cpu()) { 412 put_cpu(); 413 smp_call_function_single(newchannel->target_cpu, 414 percpu_channel_enq, 415 newchannel, true); 416 } else { 417 percpu_channel_enq(newchannel); 418 put_cpu(); 419 } 420 421 /* 422 * This state is used to indicate a successful open 423 * so that when we do close the channel normally, we 424 * can cleanup properly 425 */ 426 newchannel->state = CHANNEL_OPEN_STATE; 427 428 if (!fnew) { 429 if (channel->sc_creation_callback != NULL) 430 channel->sc_creation_callback(newchannel); 431 return; 432 } 433 434 /* 435 * Start the process of binding this offer to the driver 436 * We need to set the DeviceObject field before calling 437 * vmbus_child_dev_add() 438 */ 439 newchannel->device_obj = vmbus_device_create( 440 &newchannel->offermsg.offer.if_type, 441 &newchannel->offermsg.offer.if_instance, 442 newchannel); 443 if (!newchannel->device_obj) 444 goto err_deq_chan; 445 446 newchannel->device_obj->device_id = dev_type; 447 /* 448 * Add the new device to the bus. This will kick off device-driver 449 * binding which eventually invokes the device driver's AddDevice() 450 * method. 451 */ 452 if (vmbus_device_register(newchannel->device_obj) != 0) { 453 pr_err("unable to add child device object (relid %d)\n", 454 newchannel->offermsg.child_relid); 455 kfree(newchannel->device_obj); 456 goto err_deq_chan; 457 } 458 return; 459 460 err_deq_chan: 461 vmbus_release_relid(newchannel->offermsg.child_relid); 462 463 mutex_lock(&vmbus_connection.channel_mutex); 464 list_del(&newchannel->listentry); 465 mutex_unlock(&vmbus_connection.channel_mutex); 466 467 if (newchannel->target_cpu != get_cpu()) { 468 put_cpu(); 469 smp_call_function_single(newchannel->target_cpu, 470 percpu_channel_deq, newchannel, true); 471 } else { 472 percpu_channel_deq(newchannel); 473 put_cpu(); 474 } 475 476 err_free_chan: 477 free_channel(newchannel); 478 } 479 480 /* 481 * We use this state to statically distribute the channel interrupt load. 482 */ 483 static int next_numa_node_id; 484 485 /* 486 * Starting with Win8, we can statically distribute the incoming 487 * channel interrupt load by binding a channel to VCPU. 488 * We do this in a hierarchical fashion: 489 * First distribute the primary channels across available NUMA nodes 490 * and then distribute the subchannels amongst the CPUs in the NUMA 491 * node assigned to the primary channel. 492 * 493 * For pre-win8 hosts or non-performance critical channels we assign the 494 * first CPU in the first NUMA node. 495 */ 496 static void init_vp_index(struct vmbus_channel *channel, u16 dev_type) 497 { 498 u32 cur_cpu; 499 bool perf_chn = vmbus_devs[dev_type].perf_device; 500 struct vmbus_channel *primary = channel->primary_channel; 501 int next_node; 502 struct cpumask available_mask; 503 struct cpumask *alloced_mask; 504 505 if ((vmbus_proto_version == VERSION_WS2008) || 506 (vmbus_proto_version == VERSION_WIN7) || (!perf_chn)) { 507 /* 508 * Prior to win8, all channel interrupts are 509 * delivered on cpu 0. 510 * Also if the channel is not a performance critical 511 * channel, bind it to cpu 0. 512 */ 513 channel->numa_node = 0; 514 channel->target_cpu = 0; 515 channel->target_vp = hv_context.vp_index[0]; 516 return; 517 } 518 519 /* 520 * We distribute primary channels evenly across all the available 521 * NUMA nodes and within the assigned NUMA node we will assign the 522 * first available CPU to the primary channel. 523 * The sub-channels will be assigned to the CPUs available in the 524 * NUMA node evenly. 525 */ 526 if (!primary) { 527 while (true) { 528 next_node = next_numa_node_id++; 529 if (next_node == nr_node_ids) 530 next_node = next_numa_node_id = 0; 531 if (cpumask_empty(cpumask_of_node(next_node))) 532 continue; 533 break; 534 } 535 channel->numa_node = next_node; 536 primary = channel; 537 } 538 alloced_mask = &hv_context.hv_numa_map[primary->numa_node]; 539 540 if (cpumask_weight(alloced_mask) == 541 cpumask_weight(cpumask_of_node(primary->numa_node))) { 542 /* 543 * We have cycled through all the CPUs in the node; 544 * reset the alloced map. 545 */ 546 cpumask_clear(alloced_mask); 547 } 548 549 cpumask_xor(&available_mask, alloced_mask, 550 cpumask_of_node(primary->numa_node)); 551 552 cur_cpu = -1; 553 554 /* 555 * Normally Hyper-V host doesn't create more subchannels than there 556 * are VCPUs on the node but it is possible when not all present VCPUs 557 * on the node are initialized by guest. Clear the alloced_cpus_in_node 558 * to start over. 559 */ 560 if (cpumask_equal(&primary->alloced_cpus_in_node, 561 cpumask_of_node(primary->numa_node))) 562 cpumask_clear(&primary->alloced_cpus_in_node); 563 564 while (true) { 565 cur_cpu = cpumask_next(cur_cpu, &available_mask); 566 if (cur_cpu >= nr_cpu_ids) { 567 cur_cpu = -1; 568 cpumask_copy(&available_mask, 569 cpumask_of_node(primary->numa_node)); 570 continue; 571 } 572 573 /* 574 * NOTE: in the case of sub-channel, we clear the sub-channel 575 * related bit(s) in primary->alloced_cpus_in_node in 576 * hv_process_channel_removal(), so when we reload drivers 577 * like hv_netvsc in SMP guest, here we're able to re-allocate 578 * bit from primary->alloced_cpus_in_node. 579 */ 580 if (!cpumask_test_cpu(cur_cpu, 581 &primary->alloced_cpus_in_node)) { 582 cpumask_set_cpu(cur_cpu, 583 &primary->alloced_cpus_in_node); 584 cpumask_set_cpu(cur_cpu, alloced_mask); 585 break; 586 } 587 } 588 589 channel->target_cpu = cur_cpu; 590 channel->target_vp = hv_context.vp_index[cur_cpu]; 591 } 592 593 static void vmbus_wait_for_unload(void) 594 { 595 int cpu = smp_processor_id(); 596 void *page_addr = hv_context.synic_message_page[cpu]; 597 struct hv_message *msg = (struct hv_message *)page_addr + 598 VMBUS_MESSAGE_SINT; 599 struct vmbus_channel_message_header *hdr; 600 bool unloaded = false; 601 602 while (1) { 603 if (msg->header.message_type == HVMSG_NONE) { 604 mdelay(10); 605 continue; 606 } 607 608 hdr = (struct vmbus_channel_message_header *)msg->u.payload; 609 if (hdr->msgtype == CHANNELMSG_UNLOAD_RESPONSE) 610 unloaded = true; 611 612 msg->header.message_type = HVMSG_NONE; 613 /* 614 * header.message_type needs to be written before we do 615 * wrmsrl() below. 616 */ 617 mb(); 618 619 if (msg->header.message_flags.msg_pending) 620 wrmsrl(HV_X64_MSR_EOM, 0); 621 622 if (unloaded) 623 break; 624 } 625 } 626 627 /* 628 * vmbus_unload_response - Handler for the unload response. 629 */ 630 static void vmbus_unload_response(struct vmbus_channel_message_header *hdr) 631 { 632 /* 633 * This is a global event; just wakeup the waiting thread. 634 * Once we successfully unload, we can cleanup the monitor state. 635 */ 636 complete(&vmbus_connection.unload_event); 637 } 638 639 void vmbus_initiate_unload(void) 640 { 641 struct vmbus_channel_message_header hdr; 642 643 /* Pre-Win2012R2 hosts don't support reconnect */ 644 if (vmbus_proto_version < VERSION_WIN8_1) 645 return; 646 647 init_completion(&vmbus_connection.unload_event); 648 memset(&hdr, 0, sizeof(struct vmbus_channel_message_header)); 649 hdr.msgtype = CHANNELMSG_UNLOAD; 650 vmbus_post_msg(&hdr, sizeof(struct vmbus_channel_message_header)); 651 652 /* 653 * vmbus_initiate_unload() is also called on crash and the crash can be 654 * happening in an interrupt context, where scheduling is impossible. 655 */ 656 if (!in_interrupt()) 657 wait_for_completion(&vmbus_connection.unload_event); 658 else 659 vmbus_wait_for_unload(); 660 } 661 662 /* 663 * vmbus_onoffer - Handler for channel offers from vmbus in parent partition. 664 * 665 */ 666 static void vmbus_onoffer(struct vmbus_channel_message_header *hdr) 667 { 668 struct vmbus_channel_offer_channel *offer; 669 struct vmbus_channel *newchannel; 670 671 offer = (struct vmbus_channel_offer_channel *)hdr; 672 673 /* Allocate the channel object and save this offer. */ 674 newchannel = alloc_channel(); 675 if (!newchannel) { 676 pr_err("Unable to allocate channel object\n"); 677 return; 678 } 679 680 /* 681 * By default we setup state to enable batched 682 * reading. A specific service can choose to 683 * disable this prior to opening the channel. 684 */ 685 newchannel->batched_reading = true; 686 687 /* 688 * Setup state for signalling the host. 689 */ 690 newchannel->sig_event = (struct hv_input_signal_event *) 691 (ALIGN((unsigned long) 692 &newchannel->sig_buf, 693 HV_HYPERCALL_PARAM_ALIGN)); 694 695 newchannel->sig_event->connectionid.asu32 = 0; 696 newchannel->sig_event->connectionid.u.id = VMBUS_EVENT_CONNECTION_ID; 697 newchannel->sig_event->flag_number = 0; 698 newchannel->sig_event->rsvdz = 0; 699 700 if (vmbus_proto_version != VERSION_WS2008) { 701 newchannel->is_dedicated_interrupt = 702 (offer->is_dedicated_interrupt != 0); 703 newchannel->sig_event->connectionid.u.id = 704 offer->connection_id; 705 } 706 707 memcpy(&newchannel->offermsg, offer, 708 sizeof(struct vmbus_channel_offer_channel)); 709 newchannel->monitor_grp = (u8)offer->monitorid / 32; 710 newchannel->monitor_bit = (u8)offer->monitorid % 32; 711 712 vmbus_process_offer(newchannel); 713 } 714 715 /* 716 * vmbus_onoffer_rescind - Rescind offer handler. 717 * 718 * We queue a work item to process this offer synchronously 719 */ 720 static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) 721 { 722 struct vmbus_channel_rescind_offer *rescind; 723 struct vmbus_channel *channel; 724 unsigned long flags; 725 struct device *dev; 726 727 rescind = (struct vmbus_channel_rescind_offer *)hdr; 728 channel = relid2channel(rescind->child_relid); 729 730 if (channel == NULL) { 731 /* 732 * This is very impossible, because in 733 * vmbus_process_offer(), we have already invoked 734 * vmbus_release_relid() on error. 735 */ 736 return; 737 } 738 739 spin_lock_irqsave(&channel->lock, flags); 740 channel->rescind = true; 741 spin_unlock_irqrestore(&channel->lock, flags); 742 743 if (channel->device_obj) { 744 /* 745 * We will have to unregister this device from the 746 * driver core. 747 */ 748 dev = get_device(&channel->device_obj->device); 749 if (dev) { 750 vmbus_device_unregister(channel->device_obj); 751 put_device(dev); 752 } 753 } else { 754 hv_process_channel_removal(channel, 755 channel->offermsg.child_relid); 756 } 757 } 758 759 /* 760 * vmbus_onoffers_delivered - 761 * This is invoked when all offers have been delivered. 762 * 763 * Nothing to do here. 764 */ 765 static void vmbus_onoffers_delivered( 766 struct vmbus_channel_message_header *hdr) 767 { 768 } 769 770 /* 771 * vmbus_onopen_result - Open result handler. 772 * 773 * This is invoked when we received a response to our channel open request. 774 * Find the matching request, copy the response and signal the requesting 775 * thread. 776 */ 777 static void vmbus_onopen_result(struct vmbus_channel_message_header *hdr) 778 { 779 struct vmbus_channel_open_result *result; 780 struct vmbus_channel_msginfo *msginfo; 781 struct vmbus_channel_message_header *requestheader; 782 struct vmbus_channel_open_channel *openmsg; 783 unsigned long flags; 784 785 result = (struct vmbus_channel_open_result *)hdr; 786 787 /* 788 * Find the open msg, copy the result and signal/unblock the wait event 789 */ 790 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 791 792 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, 793 msglistentry) { 794 requestheader = 795 (struct vmbus_channel_message_header *)msginfo->msg; 796 797 if (requestheader->msgtype == CHANNELMSG_OPENCHANNEL) { 798 openmsg = 799 (struct vmbus_channel_open_channel *)msginfo->msg; 800 if (openmsg->child_relid == result->child_relid && 801 openmsg->openid == result->openid) { 802 memcpy(&msginfo->response.open_result, 803 result, 804 sizeof( 805 struct vmbus_channel_open_result)); 806 complete(&msginfo->waitevent); 807 break; 808 } 809 } 810 } 811 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 812 } 813 814 /* 815 * vmbus_ongpadl_created - GPADL created handler. 816 * 817 * This is invoked when we received a response to our gpadl create request. 818 * Find the matching request, copy the response and signal the requesting 819 * thread. 820 */ 821 static void vmbus_ongpadl_created(struct vmbus_channel_message_header *hdr) 822 { 823 struct vmbus_channel_gpadl_created *gpadlcreated; 824 struct vmbus_channel_msginfo *msginfo; 825 struct vmbus_channel_message_header *requestheader; 826 struct vmbus_channel_gpadl_header *gpadlheader; 827 unsigned long flags; 828 829 gpadlcreated = (struct vmbus_channel_gpadl_created *)hdr; 830 831 /* 832 * Find the establish msg, copy the result and signal/unblock the wait 833 * event 834 */ 835 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 836 837 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, 838 msglistentry) { 839 requestheader = 840 (struct vmbus_channel_message_header *)msginfo->msg; 841 842 if (requestheader->msgtype == CHANNELMSG_GPADL_HEADER) { 843 gpadlheader = 844 (struct vmbus_channel_gpadl_header *)requestheader; 845 846 if ((gpadlcreated->child_relid == 847 gpadlheader->child_relid) && 848 (gpadlcreated->gpadl == gpadlheader->gpadl)) { 849 memcpy(&msginfo->response.gpadl_created, 850 gpadlcreated, 851 sizeof( 852 struct vmbus_channel_gpadl_created)); 853 complete(&msginfo->waitevent); 854 break; 855 } 856 } 857 } 858 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 859 } 860 861 /* 862 * vmbus_ongpadl_torndown - GPADL torndown handler. 863 * 864 * This is invoked when we received a response to our gpadl teardown request. 865 * Find the matching request, copy the response and signal the requesting 866 * thread. 867 */ 868 static void vmbus_ongpadl_torndown( 869 struct vmbus_channel_message_header *hdr) 870 { 871 struct vmbus_channel_gpadl_torndown *gpadl_torndown; 872 struct vmbus_channel_msginfo *msginfo; 873 struct vmbus_channel_message_header *requestheader; 874 struct vmbus_channel_gpadl_teardown *gpadl_teardown; 875 unsigned long flags; 876 877 gpadl_torndown = (struct vmbus_channel_gpadl_torndown *)hdr; 878 879 /* 880 * Find the open msg, copy the result and signal/unblock the wait event 881 */ 882 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 883 884 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, 885 msglistentry) { 886 requestheader = 887 (struct vmbus_channel_message_header *)msginfo->msg; 888 889 if (requestheader->msgtype == CHANNELMSG_GPADL_TEARDOWN) { 890 gpadl_teardown = 891 (struct vmbus_channel_gpadl_teardown *)requestheader; 892 893 if (gpadl_torndown->gpadl == gpadl_teardown->gpadl) { 894 memcpy(&msginfo->response.gpadl_torndown, 895 gpadl_torndown, 896 sizeof( 897 struct vmbus_channel_gpadl_torndown)); 898 complete(&msginfo->waitevent); 899 break; 900 } 901 } 902 } 903 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 904 } 905 906 /* 907 * vmbus_onversion_response - Version response handler 908 * 909 * This is invoked when we received a response to our initiate contact request. 910 * Find the matching request, copy the response and signal the requesting 911 * thread. 912 */ 913 static void vmbus_onversion_response( 914 struct vmbus_channel_message_header *hdr) 915 { 916 struct vmbus_channel_msginfo *msginfo; 917 struct vmbus_channel_message_header *requestheader; 918 struct vmbus_channel_version_response *version_response; 919 unsigned long flags; 920 921 version_response = (struct vmbus_channel_version_response *)hdr; 922 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 923 924 list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, 925 msglistentry) { 926 requestheader = 927 (struct vmbus_channel_message_header *)msginfo->msg; 928 929 if (requestheader->msgtype == 930 CHANNELMSG_INITIATE_CONTACT) { 931 memcpy(&msginfo->response.version_response, 932 version_response, 933 sizeof(struct vmbus_channel_version_response)); 934 complete(&msginfo->waitevent); 935 } 936 } 937 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 938 } 939 940 /* Channel message dispatch table */ 941 struct vmbus_channel_message_table_entry 942 channel_message_table[CHANNELMSG_COUNT] = { 943 {CHANNELMSG_INVALID, 0, NULL}, 944 {CHANNELMSG_OFFERCHANNEL, 0, vmbus_onoffer}, 945 {CHANNELMSG_RESCIND_CHANNELOFFER, 0, vmbus_onoffer_rescind}, 946 {CHANNELMSG_REQUESTOFFERS, 0, NULL}, 947 {CHANNELMSG_ALLOFFERS_DELIVERED, 1, vmbus_onoffers_delivered}, 948 {CHANNELMSG_OPENCHANNEL, 0, NULL}, 949 {CHANNELMSG_OPENCHANNEL_RESULT, 1, vmbus_onopen_result}, 950 {CHANNELMSG_CLOSECHANNEL, 0, NULL}, 951 {CHANNELMSG_GPADL_HEADER, 0, NULL}, 952 {CHANNELMSG_GPADL_BODY, 0, NULL}, 953 {CHANNELMSG_GPADL_CREATED, 1, vmbus_ongpadl_created}, 954 {CHANNELMSG_GPADL_TEARDOWN, 0, NULL}, 955 {CHANNELMSG_GPADL_TORNDOWN, 1, vmbus_ongpadl_torndown}, 956 {CHANNELMSG_RELID_RELEASED, 0, NULL}, 957 {CHANNELMSG_INITIATE_CONTACT, 0, NULL}, 958 {CHANNELMSG_VERSION_RESPONSE, 1, vmbus_onversion_response}, 959 {CHANNELMSG_UNLOAD, 0, NULL}, 960 {CHANNELMSG_UNLOAD_RESPONSE, 1, vmbus_unload_response}, 961 }; 962 963 /* 964 * vmbus_onmessage - Handler for channel protocol messages. 965 * 966 * This is invoked in the vmbus worker thread context. 967 */ 968 void vmbus_onmessage(void *context) 969 { 970 struct hv_message *msg = context; 971 struct vmbus_channel_message_header *hdr; 972 int size; 973 974 hdr = (struct vmbus_channel_message_header *)msg->u.payload; 975 size = msg->header.payload_size; 976 977 if (hdr->msgtype >= CHANNELMSG_COUNT) { 978 pr_err("Received invalid channel message type %d size %d\n", 979 hdr->msgtype, size); 980 print_hex_dump_bytes("", DUMP_PREFIX_NONE, 981 (unsigned char *)msg->u.payload, size); 982 return; 983 } 984 985 if (channel_message_table[hdr->msgtype].message_handler) 986 channel_message_table[hdr->msgtype].message_handler(hdr); 987 else 988 pr_err("Unhandled channel message type %d\n", hdr->msgtype); 989 } 990 991 /* 992 * vmbus_request_offers - Send a request to get all our pending offers. 993 */ 994 int vmbus_request_offers(void) 995 { 996 struct vmbus_channel_message_header *msg; 997 struct vmbus_channel_msginfo *msginfo; 998 int ret; 999 1000 msginfo = kmalloc(sizeof(*msginfo) + 1001 sizeof(struct vmbus_channel_message_header), 1002 GFP_KERNEL); 1003 if (!msginfo) 1004 return -ENOMEM; 1005 1006 msg = (struct vmbus_channel_message_header *)msginfo->msg; 1007 1008 msg->msgtype = CHANNELMSG_REQUESTOFFERS; 1009 1010 1011 ret = vmbus_post_msg(msg, 1012 sizeof(struct vmbus_channel_message_header)); 1013 if (ret != 0) { 1014 pr_err("Unable to request offers - %d\n", ret); 1015 1016 goto cleanup; 1017 } 1018 1019 cleanup: 1020 kfree(msginfo); 1021 1022 return ret; 1023 } 1024 1025 /* 1026 * Retrieve the (sub) channel on which to send an outgoing request. 1027 * When a primary channel has multiple sub-channels, we try to 1028 * distribute the load equally amongst all available channels. 1029 */ 1030 struct vmbus_channel *vmbus_get_outgoing_channel(struct vmbus_channel *primary) 1031 { 1032 struct list_head *cur, *tmp; 1033 int cur_cpu; 1034 struct vmbus_channel *cur_channel; 1035 struct vmbus_channel *outgoing_channel = primary; 1036 int next_channel; 1037 int i = 1; 1038 1039 if (list_empty(&primary->sc_list)) 1040 return outgoing_channel; 1041 1042 next_channel = primary->next_oc++; 1043 1044 if (next_channel > (primary->num_sc)) { 1045 primary->next_oc = 0; 1046 return outgoing_channel; 1047 } 1048 1049 cur_cpu = hv_context.vp_index[get_cpu()]; 1050 put_cpu(); 1051 list_for_each_safe(cur, tmp, &primary->sc_list) { 1052 cur_channel = list_entry(cur, struct vmbus_channel, sc_list); 1053 if (cur_channel->state != CHANNEL_OPENED_STATE) 1054 continue; 1055 1056 if (cur_channel->target_vp == cur_cpu) 1057 return cur_channel; 1058 1059 if (i == next_channel) 1060 return cur_channel; 1061 1062 i++; 1063 } 1064 1065 return outgoing_channel; 1066 } 1067 EXPORT_SYMBOL_GPL(vmbus_get_outgoing_channel); 1068 1069 static void invoke_sc_cb(struct vmbus_channel *primary_channel) 1070 { 1071 struct list_head *cur, *tmp; 1072 struct vmbus_channel *cur_channel; 1073 1074 if (primary_channel->sc_creation_callback == NULL) 1075 return; 1076 1077 list_for_each_safe(cur, tmp, &primary_channel->sc_list) { 1078 cur_channel = list_entry(cur, struct vmbus_channel, sc_list); 1079 1080 primary_channel->sc_creation_callback(cur_channel); 1081 } 1082 } 1083 1084 void vmbus_set_sc_create_callback(struct vmbus_channel *primary_channel, 1085 void (*sc_cr_cb)(struct vmbus_channel *new_sc)) 1086 { 1087 primary_channel->sc_creation_callback = sc_cr_cb; 1088 } 1089 EXPORT_SYMBOL_GPL(vmbus_set_sc_create_callback); 1090 1091 bool vmbus_are_subchannels_present(struct vmbus_channel *primary) 1092 { 1093 bool ret; 1094 1095 ret = !list_empty(&primary->sc_list); 1096 1097 if (ret) { 1098 /* 1099 * Invoke the callback on sub-channel creation. 1100 * This will present a uniform interface to the 1101 * clients. 1102 */ 1103 invoke_sc_cb(primary); 1104 } 1105 1106 return ret; 1107 } 1108 EXPORT_SYMBOL_GPL(vmbus_are_subchannels_present); 1109