drivers/staging/hv/channel_mgmt.c

   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
  32 #include "hyperv.h"
  33 #include "hyperv_vmbus.h"
  34
  35 struct vmbus_channel_message_table_entry {
  36         enum vmbus_channel_message_type message_type;
  37         void (*message_handler)(struct vmbus_channel_message_header *msg);
  38 };
  39
  40 #define MAX_MSG_TYPES                    4
  41 #define MAX_NUM_DEVICE_CLASSES_SUPPORTED 8
  42
  43 static const struct hv_guid
  44         supported_device_classes[MAX_NUM_DEVICE_CLASSES_SUPPORTED] = {
  45         /* {ba6163d9-04a1-4d29-b605-72e2ffb1dc7f} */
  46         /* Storage - SCSI */
  47         {
  48                 .data  = {
  49                         0xd9, 0x63, 0x61, 0xba, 0xa1, 0x04, 0x29, 0x4d,
  50                         0xb6, 0x05, 0x72, 0xe2, 0xff, 0xb1, 0xdc, 0x7f
  51                 }
  52         },
  53
  54         /* {F8615163-DF3E-46c5-913F-F2D2F965ED0E} */
  55         /* Network */
  56         {
  57                 .data = {
  58                         0x63, 0x51, 0x61, 0xF8, 0x3E, 0xDF, 0xc5, 0x46,
  59                         0x91, 0x3F, 0xF2, 0xD2, 0xF9, 0x65, 0xED, 0x0E
  60                 }
  61         },
  62
  63         /* {CFA8B69E-5B4A-4cc0-B98B-8BA1A1F3F95A} */
  64         /* Input */
  65         {
  66                 .data = {
  67                         0x9E, 0xB6, 0xA8, 0xCF, 0x4A, 0x5B, 0xc0, 0x4c,
  68                         0xB9, 0x8B, 0x8B, 0xA1, 0xA1, 0xF3, 0xF9, 0x5A
  69                 }
  70         },
  71
  72         /* {32412632-86cb-44a2-9b5c-50d1417354f5} */
  73         /* IDE */
  74         {
  75                 .data = {
  76                         0x32, 0x26, 0x41, 0x32, 0xcb, 0x86, 0xa2, 0x44,
  77                         0x9b, 0x5c, 0x50, 0xd1, 0x41, 0x73, 0x54, 0xf5
  78                 }
  79         },
  80         /* 0E0B6031-5213-4934-818B-38D90CED39DB */
  81         /* Shutdown */
  82         {
  83                 .data = {
  84                         0x31, 0x60, 0x0B, 0X0E, 0x13, 0x52, 0x34, 0x49,
  85                         0x81, 0x8B, 0x38, 0XD9, 0x0C, 0xED, 0x39, 0xDB
  86                 }
  87         },
  88         /* {9527E630-D0AE-497b-ADCE-E80AB0175CAF} */
  89         /* TimeSync */
  90         {
  91                 .data = {
  92                         0x30, 0xe6, 0x27, 0x95, 0xae, 0xd0, 0x7b, 0x49,
  93                         0xad, 0xce, 0xe8, 0x0a, 0xb0, 0x17, 0x5c, 0xaf
  94                 }
  95         },
  96         /* {57164f39-9115-4e78-ab55-382f3bd5422d} */
  97         /* Heartbeat */
  98         {
  99                 .data = {
 100                         0x39, 0x4f, 0x16, 0x57, 0x15, 0x91, 0x78, 0x4e,
 101                         0xab, 0x55, 0x38, 0x2f, 0x3b, 0xd5, 0x42, 0x2d
 102                 }
 103         },
 104         /* {A9A0F4E7-5A45-4d96-B827-8A841E8C03E6} */
 105         /* KVP */
 106         {
 107                 .data = {
 108                         0xe7, 0xf4, 0xa0, 0xa9, 0x45, 0x5a, 0x96, 0x4d,
 109                         0xb8, 0x27, 0x8a, 0x84, 0x1e, 0x8c, 0x3,  0xe6
 110         }
 111         },
 112
 113 };
 114
 115
 116 /**
 117  * prep_negotiate_resp() - Create default response for Hyper-V Negotiate message
 118  * @icmsghdrp: Pointer to msg header structure
 119  * @icmsg_negotiate: Pointer to negotiate message structure
 120  * @buf: Raw buffer channel data
 121  *
 122  * @icmsghdrp is of type &struct icmsg_hdr.
 123  * @negop is of type &struct icmsg_negotiate.
 124  * Set up and fill in default negotiate response message. This response can
 125  * come from both the vmbus driver and the hv_utils driver. The current api
 126  * will respond properly to both Windows 2008 and Windows 2008-R2 operating
 127  * systems.
 128  *
 129  * Mainly used by Hyper-V drivers.
 130  */
 131 void prep_negotiate_resp(struct icmsg_hdr *icmsghdrp,
 132                              struct icmsg_negotiate *negop,
 133                              u8 *buf)
 134 {
 135         if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 136                 icmsghdrp->icmsgsize = 0x10;
 137
 138                 negop = (struct icmsg_negotiate *)&buf[
 139                         sizeof(struct vmbuspipe_hdr) +
 140                         sizeof(struct icmsg_hdr)];
 141
 142                 if (negop->icframe_vercnt == 2 &&
 143                    negop->icversion_data[1].major == 3) {
 144                         negop->icversion_data[0].major = 3;
 145                         negop->icversion_data[0].minor = 0;
 146                         negop->icversion_data[1].major = 3;
 147                         negop->icversion_data[1].minor = 0;
 148                 } else {
 149                         negop->icversion_data[0].major = 1;
 150                         negop->icversion_data[0].minor = 0;
 151                         negop->icversion_data[1].major = 1;
 152                         negop->icversion_data[1].minor = 0;
 153                 }
 154
 155                 negop->icframe_vercnt = 1;
 156                 negop->icmsg_vercnt = 1;
 157         }
 158 }
 159 EXPORT_SYMBOL(prep_negotiate_resp);
 160
 161 /**
 162  * chn_cb_negotiate() - Default handler for non IDE/SCSI/NETWORK
 163  * Hyper-V requests
 164  * @context: Pointer to argument structure.
 165  *
 166  * Set up the default handler for non device driver specific requests
 167  * from Hyper-V. This stub responds to the default negotiate messages
 168  * that come in for every non IDE/SCSI/Network request.
 169  * This behavior is normally overwritten in the hv_utils driver. That
 170  * driver handles requests like graceful shutdown, heartbeats etc.
 171  *
 172  * Mainly used by Hyper-V drivers.
 173  */
 174 void chn_cb_negotiate(void *context)
 175 {
 176         struct vmbus_channel *channel = context;
 177         u8 *buf;
 178         u32 buflen, recvlen;
 179         u64 requestid;
 180
 181         struct icmsg_hdr *icmsghdrp;
 182         struct icmsg_negotiate *negop = NULL;
 183
 184         if (channel->util_index >= 0) {
 185                 /*
 186                  * This is a properly initialized util channel.
 187                  * Route this callback appropriately and setup state
 188                  * so that we don't need to reroute again.
 189                  */
 190                 if (hv_cb_utils[channel->util_index].callback != NULL) {
 191                         /*
 192                          * The util driver has established a handler for
 193                          * this service; do the magic.
 194                          */
 195                         channel->onchannel_callback =
 196                         hv_cb_utils[channel->util_index].callback;
 197                         (hv_cb_utils[channel->util_index].callback)(channel);
 198                         return;
 199                 }
 200         }
 201
 202         buflen = PAGE_SIZE;
 203         buf = kmalloc(buflen, GFP_ATOMIC);
 204
 205         vmbus_recvpacket(channel, buf, buflen, &recvlen, &requestid);
 206
 207         if (recvlen > 0) {
 208                 icmsghdrp = (struct icmsg_hdr *)&buf[
 209                         sizeof(struct vmbuspipe_hdr)];
 210
 211                 prep_negotiate_resp(icmsghdrp, negop, buf);
 212
 213                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 214                         | ICMSGHDRFLAG_RESPONSE;
 215
 216                 vmbus_sendpacket(channel, buf,
 217                                        recvlen, requestid,
 218                                        VM_PKT_DATA_INBAND, 0);
 219         }
 220
 221         kfree(buf);
 222 }
 223 EXPORT_SYMBOL(chn_cb_negotiate);
 224
 225 /*
 226  * Function table used for message responses for non IDE/SCSI/Network type
 227  * messages. (Such as KVP/Shutdown etc)
 228  */
 229 struct hyperv_service_callback hv_cb_utils[MAX_MSG_TYPES] = {
 230         /* 0E0B6031-5213-4934-818B-38D90CED39DB */
 231         /* Shutdown */
 232         {
 233                 .msg_type = HV_SHUTDOWN_MSG,
 234                 .data = {
 235                         0x31, 0x60, 0x0B, 0X0E, 0x13, 0x52, 0x34, 0x49,
 236                         0x81, 0x8B, 0x38, 0XD9, 0x0C, 0xED, 0x39, 0xDB
 237                 },
 238                 .log_msg = "Shutdown channel functionality initialized"
 239         },
 240
 241         /* {9527E630-D0AE-497b-ADCE-E80AB0175CAF} */
 242         /* TimeSync */
 243         {
 244                 .msg_type = HV_TIMESYNC_MSG,
 245                 .data = {
 246                         0x30, 0xe6, 0x27, 0x95, 0xae, 0xd0, 0x7b, 0x49,
 247                         0xad, 0xce, 0xe8, 0x0a, 0xb0, 0x17, 0x5c, 0xaf
 248                 },
 249                 .log_msg = "Timesync channel functionality initialized"
 250         },
 251         /* {57164f39-9115-4e78-ab55-382f3bd5422d} */
 252         /* Heartbeat */
 253         {
 254                 .msg_type = HV_HEARTBEAT_MSG,
 255                 .data = {
 256                         0x39, 0x4f, 0x16, 0x57, 0x15, 0x91, 0x78, 0x4e,
 257                         0xab, 0x55, 0x38, 0x2f, 0x3b, 0xd5, 0x42, 0x2d
 258                 },
 259                 .log_msg = "Heartbeat channel functionality initialized"
 260         },
 261         /* {A9A0F4E7-5A45-4d96-B827-8A841E8C03E6} */
 262         /* KVP */
 263         {
 264                 .data = {
 265                         0xe7, 0xf4, 0xa0, 0xa9, 0x45, 0x5a, 0x96, 0x4d,
 266                         0xb8, 0x27, 0x8a, 0x84, 0x1e, 0x8c, 0x3,  0xe6
 267                 },
 268                 .log_msg = "KVP channel functionality initialized"
 269         },
 270 };
 271 EXPORT_SYMBOL(hv_cb_utils);
 272
 273 /*
 274  * alloc_channel - Allocate and initialize a vmbus channel object
 275  */
 276 static struct vmbus_channel *alloc_channel(void)
 277 {
 278         struct vmbus_channel *channel;
 279
 280         channel = kzalloc(sizeof(*channel), GFP_ATOMIC);
 281         if (!channel)
 282                 return NULL;
 283
 284         spin_lock_init(&channel->inbound_lock);
 285
 286         channel->controlwq = create_workqueue("hv_vmbus_ctl");
 287         if (!channel->controlwq) {
 288                 kfree(channel);
 289                 return NULL;
 290         }
 291
 292         return channel;
 293 }
 294
 295 /*
 296  * release_hannel - Release the vmbus channel object itself
 297  */
 298 static void release_channel(struct work_struct *work)
 299 {
 300         struct vmbus_channel *channel = container_of(work,
 301                                                      struct vmbus_channel,
 302                                                      work);
 303
 304         destroy_workqueue(channel->controlwq);
 305
 306         kfree(channel);
 307 }
 308
 309 /*
 310  * free_channel - Release the resources used by the vmbus channel object
 311  */
 312 void free_channel(struct vmbus_channel *channel)
 313 {
 314
 315         /*
 316          * We have to release the channel's workqueue/thread in the vmbus's
 317          * workqueue/thread context
 318          * ie we can't destroy ourselves.
 319          */
 320         INIT_WORK(&channel->work, release_channel);
 321         queue_work(vmbus_connection.work_queue, &channel->work);
 322 }
 323
 324
 325
 326 /*
 327  * vmbus_process_rescind_offer -
 328  * Rescind the offer by initiating a device removal
 329  */
 330 static void vmbus_process_rescind_offer(struct work_struct *work)
 331 {
 332         struct vmbus_channel *channel = container_of(work,
 333                                                      struct vmbus_channel,
 334                                                      work);
 335
 336         vmbus_child_device_unregister(channel->device_obj);
 337 }
 338
 339 /*
 340  * vmbus_process_offer - Process the offer by creating a channel/device
 341  * associated with this offer
 342  */
 343 static void vmbus_process_offer(struct work_struct *work)
 344 {
 345         struct vmbus_channel *newchannel = container_of(work,
 346                                                         struct vmbus_channel,
 347                                                         work);
 348         struct vmbus_channel *channel;
 349         bool fnew = true;
 350         int ret;
 351         int cnt;
 352         unsigned long flags;
 353
 354         /* The next possible work is rescind handling */
 355         INIT_WORK(&newchannel->work, vmbus_process_rescind_offer);
 356
 357         /* Make sure this is a new offer */
 358         spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
 359
 360         list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
 361                 if (!memcmp(&channel->offermsg.offer.if_type,
 362                             &newchannel->offermsg.offer.if_type,
 363                             sizeof(struct hv_guid)) &&
 364                     !memcmp(&channel->offermsg.offer.if_instance,
 365                             &newchannel->offermsg.offer.if_instance,
 366                             sizeof(struct hv_guid))) {
 367                         fnew = false;
 368                         break;
 369                 }
 370         }
 371
 372         if (fnew)
 373                 list_add_tail(&newchannel->listentry,
 374                               &vmbus_connection.chn_list);
 375
 376         spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
 377
 378         if (!fnew) {
 379                 free_channel(newchannel);
 380                 return;
 381         }
 382
 383         /*
 384          * Start the process of binding this offer to the driver
 385          * We need to set the DeviceObject field before calling
 386          * vmbus_child_dev_add()
 387          */
 388         newchannel->device_obj = vmbus_child_device_create(
 389                 &newchannel->offermsg.offer.if_type,
 390                 &newchannel->offermsg.offer.if_instance,
 391                 newchannel);
 392
 393         /*
 394          * Add the new device to the bus. This will kick off device-driver
 395          * binding which eventually invokes the device driver's AddDevice()
 396          * method.
 397          */
 398         ret = vmbus_child_device_register(newchannel->device_obj);
 399         if (ret != 0) {
 400                 pr_err("unable to add child device object (relid %d)\n",
 401                            newchannel->offermsg.child_relid);
 402
 403                 spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
 404                 list_del(&newchannel->listentry);
 405                 spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
 406
 407                 free_channel(newchannel);
 408         } else {
 409                 /*
 410                  * This state is used to indicate a successful open
 411                  * so that when we do close the channel normally, we
 412                  * can cleanup properly
 413                  */
 414                 newchannel->state = CHANNEL_OPEN_STATE;
 415                 newchannel->util_index = -1; /* Invalid index */
 416
 417                 /* Open IC channels */
 418                 for (cnt = 0; cnt < MAX_MSG_TYPES; cnt++) {
 419                         if (memcmp(&newchannel->offermsg.offer.if_type,
 420                                    &hv_cb_utils[cnt].data,
 421                                    sizeof(struct hv_guid)) == 0 &&
 422                                 vmbus_open(newchannel, 2 * PAGE_SIZE,
 423                                                  2 * PAGE_SIZE, NULL, 0,
 424                                                  chn_cb_negotiate,
 425                                                  newchannel) == 0) {
 426                                 hv_cb_utils[cnt].channel = newchannel;
 427                                 newchannel->util_index = cnt;
 428
 429                                 pr_info("%s\n", hv_cb_utils[cnt].log_msg);
 430
 431                         }
 432                 }
 433         }
 434 }
 435
 436 /*
 437  * vmbus_onoffer - Handler for channel offers from vmbus in parent partition.
 438  *
 439  * We ignore all offers except network and storage offers. For each network and
 440  * storage offers, we create a channel object and queue a work item to the
 441  * channel object to process the offer synchronously
 442  */
 443 static void vmbus_onoffer(struct vmbus_channel_message_header *hdr)
 444 {
 445         struct vmbus_channel_offer_channel *offer;
 446         struct vmbus_channel *newchannel;
 447         struct hv_guid *guidtype;
 448         struct hv_guid *guidinstance;
 449         int i;
 450         int fsupported = 0;
 451
 452         offer = (struct vmbus_channel_offer_channel *)hdr;
 453         for (i = 0; i < MAX_NUM_DEVICE_CLASSES_SUPPORTED; i++) {
 454                 if (memcmp(&offer->offer.if_type,
 455                         &supported_device_classes[i],
 456                         sizeof(struct hv_guid)) == 0) {
 457                         fsupported = 1;
 458                         break;
 459                 }
 460         }
 461
 462         if (!fsupported)
 463                 return;
 464
 465         guidtype = &offer->offer.if_type;
 466         guidinstance = &offer->offer.if_instance;
 467
 468         /* Allocate the channel object and save this offer. */
 469         newchannel = alloc_channel();
 470         if (!newchannel) {
 471                 pr_err("Unable to allocate channel object\n");
 472                 return;
 473         }
 474
 475         memcpy(&newchannel->offermsg, offer,
 476                sizeof(struct vmbus_channel_offer_channel));
 477         newchannel->monitor_grp = (u8)offer->monitorid / 32;
 478         newchannel->monitor_bit = (u8)offer->monitorid % 32;
 479
 480         INIT_WORK(&newchannel->work, vmbus_process_offer);
 481         queue_work(newchannel->controlwq, &newchannel->work);
 482 }
 483
 484 /*
 485  * vmbus_onoffer_rescind - Rescind offer handler.
 486  *
 487  * We queue a work item to process this offer synchronously
 488  */
 489 static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
 490 {
 491         struct vmbus_channel_rescind_offer *rescind;
 492         struct vmbus_channel *channel;
 493
 494         rescind = (struct vmbus_channel_rescind_offer *)hdr;
 495         channel = relid2channel(rescind->child_relid);
 496
 497         if (channel == NULL)
 498                 /* Just return here, no channel found */
 499                 return;
 500
 501         /* work is initialized for vmbus_process_rescind_offer() from
 502          * vmbus_process_offer() where the channel got created */
 503         queue_work(channel->controlwq, &channel->work);
 504 }
 505
 506 /*
 507  * vmbus_onoffers_delivered -
 508  * This is invoked when all offers have been delivered.
 509  *
 510  * Nothing to do here.
 511  */
 512 static void vmbus_onoffers_delivered(
 513                         struct vmbus_channel_message_header *hdr)
 514 {
 515 }
 516
 517 /*
 518  * vmbus_onopen_result - Open result handler.
 519  *
 520  * This is invoked when we received a response to our channel open request.
 521  * Find the matching request, copy the response and signal the requesting
 522  * thread.
 523  */
 524 static void vmbus_onopen_result(struct vmbus_channel_message_header *hdr)
 525 {
 526         struct vmbus_channel_open_result *result;
 527         struct vmbus_channel_msginfo *msginfo;
 528         struct vmbus_channel_message_header *requestheader;
 529         struct vmbus_channel_open_channel *openmsg;
 530         unsigned long flags;
 531
 532         result = (struct vmbus_channel_open_result *)hdr;
 533
 534         /*
 535          * Find the open msg, copy the result and signal/unblock the wait event
 536          */
 537         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 538
 539         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 540                                 msglistentry) {
 541                 requestheader =
 542                         (struct vmbus_channel_message_header *)msginfo->msg;
 543
 544                 if (requestheader->msgtype == CHANNELMSG_OPENCHANNEL) {
 545                         openmsg =
 546                         (struct vmbus_channel_open_channel *)msginfo->msg;
 547                         if (openmsg->child_relid == result->child_relid &&
 548                             openmsg->openid == result->openid) {
 549                                 memcpy(&msginfo->response.open_result,
 550                                        result,
 551                                        sizeof(
 552                                         struct vmbus_channel_open_result));
 553                                 complete(&msginfo->waitevent);
 554                                 break;
 555                         }
 556                 }
 557         }
 558         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 559 }
 560
 561 /*
 562  * vmbus_ongpadl_created - GPADL created handler.
 563  *
 564  * This is invoked when we received a response to our gpadl create request.
 565  * Find the matching request, copy the response and signal the requesting
 566  * thread.
 567  */
 568 static void vmbus_ongpadl_created(struct vmbus_channel_message_header *hdr)
 569 {
 570         struct vmbus_channel_gpadl_created *gpadlcreated;
 571         struct vmbus_channel_msginfo *msginfo;
 572         struct vmbus_channel_message_header *requestheader;
 573         struct vmbus_channel_gpadl_header *gpadlheader;
 574         unsigned long flags;
 575
 576         gpadlcreated = (struct vmbus_channel_gpadl_created *)hdr;
 577
 578         /*
 579          * Find the establish msg, copy the result and signal/unblock the wait
 580          * event
 581          */
 582         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 583
 584         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 585                                 msglistentry) {
 586                 requestheader =
 587                         (struct vmbus_channel_message_header *)msginfo->msg;
 588
 589                 if (requestheader->msgtype == CHANNELMSG_GPADL_HEADER) {
 590                         gpadlheader =
 591                         (struct vmbus_channel_gpadl_header *)requestheader;
 592
 593                         if ((gpadlcreated->child_relid ==
 594                              gpadlheader->child_relid) &&
 595                             (gpadlcreated->gpadl == gpadlheader->gpadl)) {
 596                                 memcpy(&msginfo->response.gpadl_created,
 597                                        gpadlcreated,
 598                                        sizeof(
 599                                         struct vmbus_channel_gpadl_created));
 600                                 complete(&msginfo->waitevent);
 601                                 break;
 602                         }
 603                 }
 604         }
 605         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 606 }
 607
 608 /*
 609  * vmbus_ongpadl_torndown - GPADL torndown handler.
 610  *
 611  * This is invoked when we received a response to our gpadl teardown request.
 612  * Find the matching request, copy the response and signal the requesting
 613  * thread.
 614  */
 615 static void vmbus_ongpadl_torndown(
 616                         struct vmbus_channel_message_header *hdr)
 617 {
 618         struct vmbus_channel_gpadl_torndown *gpadl_torndown;
 619         struct vmbus_channel_msginfo *msginfo;
 620         struct vmbus_channel_message_header *requestheader;
 621         struct vmbus_channel_gpadl_teardown *gpadl_teardown;
 622         unsigned long flags;
 623
 624         gpadl_torndown = (struct vmbus_channel_gpadl_torndown *)hdr;
 625
 626         /*
 627          * Find the open msg, copy the result and signal/unblock the wait event
 628          */
 629         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 630
 631         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 632                                 msglistentry) {
 633                 requestheader =
 634                         (struct vmbus_channel_message_header *)msginfo->msg;
 635
 636                 if (requestheader->msgtype == CHANNELMSG_GPADL_TEARDOWN) {
 637                         gpadl_teardown =
 638                         (struct vmbus_channel_gpadl_teardown *)requestheader;
 639
 640                         if (gpadl_torndown->gpadl == gpadl_teardown->gpadl) {
 641                                 memcpy(&msginfo->response.gpadl_torndown,
 642                                        gpadl_torndown,
 643                                        sizeof(
 644                                         struct vmbus_channel_gpadl_torndown));
 645                                 complete(&msginfo->waitevent);
 646                                 break;
 647                         }
 648                 }
 649         }
 650         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 651 }
 652
 653 /*
 654  * vmbus_onversion_response - Version response handler
 655  *
 656  * This is invoked when we received a response to our initiate contact request.
 657  * Find the matching request, copy the response and signal the requesting
 658  * thread.
 659  */
 660 static void vmbus_onversion_response(
 661                 struct vmbus_channel_message_header *hdr)
 662 {
 663         struct vmbus_channel_msginfo *msginfo;
 664         struct vmbus_channel_message_header *requestheader;
 665         struct vmbus_channel_initiate_contact *initiate;
 666         struct vmbus_channel_version_response *version_response;
 667         unsigned long flags;
 668
 669         version_response = (struct vmbus_channel_version_response *)hdr;
 670         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 671
 672         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 673                                 msglistentry) {
 674                 requestheader =
 675                         (struct vmbus_channel_message_header *)msginfo->msg;
 676
 677                 if (requestheader->msgtype ==
 678                     CHANNELMSG_INITIATE_CONTACT) {
 679                         initiate =
 680                         (struct vmbus_channel_initiate_contact *)requestheader;
 681                         memcpy(&msginfo->response.version_response,
 682                               version_response,
 683                               sizeof(struct vmbus_channel_version_response));
 684                         complete(&msginfo->waitevent);
 685                 }
 686         }
 687         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 688 }
 689
 690 /* Channel message dispatch table */
 691 static struct vmbus_channel_message_table_entry
 692         channel_message_table[CHANNELMSG_COUNT] = {
 693         {CHANNELMSG_INVALID,                    NULL},
 694         {CHANNELMSG_OFFERCHANNEL,               vmbus_onoffer},
 695         {CHANNELMSG_RESCIND_CHANNELOFFER,       vmbus_onoffer_rescind},
 696         {CHANNELMSG_REQUESTOFFERS,              NULL},
 697         {CHANNELMSG_ALLOFFERS_DELIVERED,        vmbus_onoffers_delivered},
 698         {CHANNELMSG_OPENCHANNEL,                NULL},
 699         {CHANNELMSG_OPENCHANNEL_RESULT, vmbus_onopen_result},
 700         {CHANNELMSG_CLOSECHANNEL,               NULL},
 701         {CHANNELMSG_GPADL_HEADER,               NULL},
 702         {CHANNELMSG_GPADL_BODY,         NULL},
 703         {CHANNELMSG_GPADL_CREATED,              vmbus_ongpadl_created},
 704         {CHANNELMSG_GPADL_TEARDOWN,             NULL},
 705         {CHANNELMSG_GPADL_TORNDOWN,             vmbus_ongpadl_torndown},
 706         {CHANNELMSG_RELID_RELEASED,             NULL},
 707         {CHANNELMSG_INITIATE_CONTACT,           NULL},
 708         {CHANNELMSG_VERSION_RESPONSE,           vmbus_onversion_response},
 709         {CHANNELMSG_UNLOAD,                     NULL},
 710 };
 711
 712 /*
 713  * vmbus_onmessage - Handler for channel protocol messages.
 714  *
 715  * This is invoked in the vmbus worker thread context.
 716  */
 717 void vmbus_onmessage(void *context)
 718 {
 719         struct hv_message *msg = context;
 720         struct vmbus_channel_message_header *hdr;
 721         int size;
 722
 723         hdr = (struct vmbus_channel_message_header *)msg->u.payload;
 724         size = msg->header.payload_size;
 725
 726         if (hdr->msgtype >= CHANNELMSG_COUNT) {
 727                 pr_err("Received invalid channel message type %d size %d\n",
 728                            hdr->msgtype, size);
 729                 print_hex_dump_bytes("", DUMP_PREFIX_NONE,
 730                                      (unsigned char *)msg->u.payload, size);
 731                 return;
 732         }
 733
 734         if (channel_message_table[hdr->msgtype].message_handler)
 735                 channel_message_table[hdr->msgtype].message_handler(hdr);
 736         else
 737                 pr_err("Unhandled channel message type %d\n", hdr->msgtype);
 738 }
 739
 740 /*
 741  * vmbus_request_offers - Send a request to get all our pending offers.
 742  */
 743 int vmbus_request_offers(void)
 744 {
 745         struct vmbus_channel_message_header *msg;
 746         struct vmbus_channel_msginfo *msginfo;
 747         int ret, t;
 748
 749         msginfo = kmalloc(sizeof(*msginfo) +
 750                           sizeof(struct vmbus_channel_message_header),
 751                           GFP_KERNEL);
 752         if (!msginfo)
 753                 return -ENOMEM;
 754
 755         init_completion(&msginfo->waitevent);
 756
 757         msg = (struct vmbus_channel_message_header *)msginfo->msg;
 758
 759         msg->msgtype = CHANNELMSG_REQUESTOFFERS;
 760
 761
 762         ret = vmbus_post_msg(msg,
 763                                sizeof(struct vmbus_channel_message_header));
 764         if (ret != 0) {
 765                 pr_err("Unable to request offers - %d\n", ret);
 766
 767                 goto cleanup;
 768         }
 769
 770         t = wait_for_completion_timeout(&msginfo->waitevent, 5*HZ);
 771         if (t == 0) {
 772                 ret = -ETIMEDOUT;
 773                 goto cleanup;
 774         }
 775
 776
 777
 778 cleanup:
 779         kfree(msginfo);
 780
 781         return ret;
 782 }
 783
 784 /* eof */