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 #include "hv_api.h"
  32 #include "logging.h"
  33 #include "vmbus_private.h"
  34 #include "utils.h"
  35
  36 struct vmbus_channel_message_table_entry {
  37         enum vmbus_channel_message_type messageType;
  38         void (*messageHandler)(struct vmbus_channel_message_header *msg);
  39 };
  40
  41 #define MAX_MSG_TYPES                    4
  42 #define MAX_NUM_DEVICE_CLASSES_SUPPORTED 8
  43
  44 static const struct hv_guid
  45         gSupportedDeviceClasses[MAX_NUM_DEVICE_CLASSES_SUPPORTED] = {
  46         /* {ba6163d9-04a1-4d29-b605-72e2ffb1dc7f} */
  47         /* Storage - SCSI */
  48         {
  49                 .data  = {
  50                         0xd9, 0x63, 0x61, 0xba, 0xa1, 0x04, 0x29, 0x4d,
  51                         0xb6, 0x05, 0x72, 0xe2, 0xff, 0xb1, 0xdc, 0x7f
  52                 }
  53         },
  54
  55         /* {F8615163-DF3E-46c5-913F-F2D2F965ED0E} */
  56         /* Network */
  57         {
  58                 .data = {
  59                         0x63, 0x51, 0x61, 0xF8, 0x3E, 0xDF, 0xc5, 0x46,
  60                         0x91, 0x3F, 0xF2, 0xD2, 0xF9, 0x65, 0xED, 0x0E
  61                 }
  62         },
  63
  64         /* {CFA8B69E-5B4A-4cc0-B98B-8BA1A1F3F95A} */
  65         /* Input */
  66         {
  67                 .data = {
  68                         0x9E, 0xB6, 0xA8, 0xCF, 0x4A, 0x5B, 0xc0, 0x4c,
  69                         0xB9, 0x8B, 0x8B, 0xA1, 0xA1, 0xF3, 0xF9, 0x5A
  70                 }
  71         },
  72
  73         /* {32412632-86cb-44a2-9b5c-50d1417354f5} */
  74         /* IDE */
  75         {
  76                 .data = {
  77                         0x32, 0x26, 0x41, 0x32, 0xcb, 0x86, 0xa2, 0x44,
  78                         0x9b, 0x5c, 0x50, 0xd1, 0x41, 0x73, 0x54, 0xf5
  79                 }
  80         },
  81         /* 0E0B6031-5213-4934-818B-38D90CED39DB */
  82         /* Shutdown */
  83         {
  84                 .data = {
  85                         0x31, 0x60, 0x0B, 0X0E, 0x13, 0x52, 0x34, 0x49,
  86                         0x81, 0x8B, 0x38, 0XD9, 0x0C, 0xED, 0x39, 0xDB
  87                 }
  88         },
  89         /* {9527E630-D0AE-497b-ADCE-E80AB0175CAF} */
  90         /* TimeSync */
  91         {
  92                 .data = {
  93                         0x30, 0xe6, 0x27, 0x95, 0xae, 0xd0, 0x7b, 0x49,
  94                         0xad, 0xce, 0xe8, 0x0a, 0xb0, 0x17, 0x5c, 0xaf
  95                 }
  96         },
  97         /* {57164f39-9115-4e78-ab55-382f3bd5422d} */
  98         /* Heartbeat */
  99         {
 100                 .data = {
 101                         0x39, 0x4f, 0x16, 0x57, 0x15, 0x91, 0x78, 0x4e,
 102                         0xab, 0x55, 0x38, 0x2f, 0x3b, 0xd5, 0x42, 0x2d
 103                 }
 104         },
 105         /* {A9A0F4E7-5A45-4d96-B827-8A841E8C03E6} */
 106         /* KVP */
 107         {
 108                 .data = {
 109                         0xe7, 0xf4, 0xa0, 0xa9, 0x45, 0x5a, 0x96, 0x4d,
 110                         0xb8, 0x27, 0x8a, 0x84, 0x1e, 0x8c, 0x3,  0xe6
 111         }
 112         },
 113
 114 };
 115
 116
 117 /**
 118  * prep_negotiate_resp() - Create default response for Hyper-V Negotiate message
 119  * @icmsghdrp: Pointer to msg header structure
 120  * @icmsg_negotiate: Pointer to negotiate message structure
 121  * @buf: Raw buffer channel data
 122  *
 123  * @icmsghdrp is of type &struct icmsg_hdr.
 124  * @negop is of type &struct icmsg_negotiate.
 125  * Set up and fill in default negotiate response message. This response can
 126  * come from both the vmbus driver and the hv_utils driver. The current api
 127  * will respond properly to both Windows 2008 and Windows 2008-R2 operating
 128  * systems.
 129  *
 130  * Mainly used by Hyper-V drivers.
 131  */
 132 void prep_negotiate_resp(struct icmsg_hdr *icmsghdrp,
 133                              struct icmsg_negotiate *negop,
 134                              u8 *buf)
 135 {
 136         if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 137                 icmsghdrp->icmsgsize = 0x10;
 138
 139                 negop = (struct icmsg_negotiate *)&buf[
 140                         sizeof(struct vmbuspipe_hdr) +
 141                         sizeof(struct icmsg_hdr)];
 142
 143                 if (negop->icframe_vercnt == 2 &&
 144                    negop->icversion_data[1].major == 3) {
 145                         negop->icversion_data[0].major = 3;
 146                         negop->icversion_data[0].minor = 0;
 147                         negop->icversion_data[1].major = 3;
 148                         negop->icversion_data[1].minor = 0;
 149                 } else {
 150                         negop->icversion_data[0].major = 1;
 151                         negop->icversion_data[0].minor = 0;
 152                         negop->icversion_data[1].major = 1;
 153                         negop->icversion_data[1].minor = 0;
 154                 }
 155
 156                 negop->icframe_vercnt = 1;
 157                 negop->icmsg_vercnt = 1;
 158         }
 159 }
 160 EXPORT_SYMBOL(prep_negotiate_resp);
 161
 162 /**
 163  * chn_cb_negotiate() - Default handler for non IDE/SCSI/NETWORK
 164  * Hyper-V requests
 165  * @context: Pointer to argument structure.
 166  *
 167  * Set up the default handler for non device driver specific requests
 168  * from Hyper-V. This stub responds to the default negotiate messages
 169  * that come in for every non IDE/SCSI/Network request.
 170  * This behavior is normally overwritten in the hv_utils driver. That
 171  * driver handles requests like gracefull shutdown, heartbeats etc.
 172  *
 173  * Mainly used by Hyper-V drivers.
 174  */
 175 void chn_cb_negotiate(void *context)
 176 {
 177         struct vmbus_channel *channel = context;
 178         u8 *buf;
 179         u32 buflen, recvlen;
 180         u64 requestid;
 181
 182         struct icmsg_hdr *icmsghdrp;
 183         struct icmsg_negotiate *negop = NULL;
 184
 185         buflen = PAGE_SIZE;
 186         buf = kmalloc(buflen, GFP_ATOMIC);
 187
 188         vmbus_recvpacket(channel, buf, buflen, &recvlen, &requestid);
 189
 190         if (recvlen > 0) {
 191                 icmsghdrp = (struct icmsg_hdr *)&buf[
 192                         sizeof(struct vmbuspipe_hdr)];
 193
 194                 prep_negotiate_resp(icmsghdrp, negop, buf);
 195
 196                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 197                         | ICMSGHDRFLAG_RESPONSE;
 198
 199                 vmbus_sendpacket(channel, buf,
 200                                        recvlen, requestid,
 201                                        VM_PKT_DATA_INBAND, 0);
 202         }
 203
 204         kfree(buf);
 205 }
 206 EXPORT_SYMBOL(chn_cb_negotiate);
 207
 208 /*
 209  * Function table used for message responses for non IDE/SCSI/Network type
 210  * messages. (Such as KVP/Shutdown etc)
 211  */
 212 struct hyperv_service_callback hv_cb_utils[MAX_MSG_TYPES] = {
 213         /* 0E0B6031-5213-4934-818B-38D90CED39DB */
 214         /* Shutdown */
 215         {
 216                 .msg_type = HV_SHUTDOWN_MSG,
 217                 .data = {
 218                         0x31, 0x60, 0x0B, 0X0E, 0x13, 0x52, 0x34, 0x49,
 219                         0x81, 0x8B, 0x38, 0XD9, 0x0C, 0xED, 0x39, 0xDB
 220                 },
 221                 .callback = chn_cb_negotiate,
 222                 .log_msg = "Shutdown channel functionality initialized"
 223         },
 224
 225         /* {9527E630-D0AE-497b-ADCE-E80AB0175CAF} */
 226         /* TimeSync */
 227         {
 228                 .msg_type = HV_TIMESYNC_MSG,
 229                 .data = {
 230                         0x30, 0xe6, 0x27, 0x95, 0xae, 0xd0, 0x7b, 0x49,
 231                         0xad, 0xce, 0xe8, 0x0a, 0xb0, 0x17, 0x5c, 0xaf
 232                 },
 233                 .callback = chn_cb_negotiate,
 234                 .log_msg = "Timesync channel functionality initialized"
 235         },
 236         /* {57164f39-9115-4e78-ab55-382f3bd5422d} */
 237         /* Heartbeat */
 238         {
 239                 .msg_type = HV_HEARTBEAT_MSG,
 240                 .data = {
 241                         0x39, 0x4f, 0x16, 0x57, 0x15, 0x91, 0x78, 0x4e,
 242                         0xab, 0x55, 0x38, 0x2f, 0x3b, 0xd5, 0x42, 0x2d
 243                 },
 244                 .callback = chn_cb_negotiate,
 245                 .log_msg = "Heartbeat channel functionality initialized"
 246         },
 247         /* {A9A0F4E7-5A45-4d96-B827-8A841E8C03E6} */
 248         /* KVP */
 249         {
 250                 .data = {
 251                         0xe7, 0xf4, 0xa0, 0xa9, 0x45, 0x5a, 0x96, 0x4d,
 252                         0xb8, 0x27, 0x8a, 0x84, 0x1e, 0x8c, 0x3,  0xe6
 253                 },
 254                 .callback = chn_cb_negotiate,
 255                 .log_msg = "KVP channel functionality initialized"
 256         },
 257 };
 258 EXPORT_SYMBOL(hv_cb_utils);
 259
 260 /*
 261  * alloc_channel - Allocate and initialize a vmbus channel object
 262  */
 263 static struct vmbus_channel *alloc_channel(void)
 264 {
 265         struct vmbus_channel *channel;
 266
 267         channel = kzalloc(sizeof(*channel), GFP_ATOMIC);
 268         if (!channel)
 269                 return NULL;
 270
 271         spin_lock_init(&channel->inbound_lock);
 272
 273         init_timer(&channel->poll_timer);
 274         channel->poll_timer.data = (unsigned long)channel;
 275         channel->poll_timer.function = vmbus_ontimer;
 276
 277         channel->controlwq = create_workqueue("hv_vmbus_ctl");
 278         if (!channel->controlwq) {
 279                 kfree(channel);
 280                 return NULL;
 281         }
 282
 283         return channel;
 284 }
 285
 286 /*
 287  * release_hannel - Release the vmbus channel object itself
 288  */
 289 static void release_channel(struct work_struct *work)
 290 {
 291         struct vmbus_channel *channel = container_of(work,
 292                                                      struct vmbus_channel,
 293                                                      work);
 294
 295         destroy_workqueue(channel->controlwq);
 296
 297         kfree(channel);
 298 }
 299
 300 /*
 301  * free_channel - Release the resources used by the vmbus channel object
 302  */
 303 void free_channel(struct vmbus_channel *channel)
 304 {
 305         del_timer_sync(&channel->poll_timer);
 306
 307         /*
 308          * We have to release the channel's workqueue/thread in the vmbus's
 309          * workqueue/thread context
 310          * ie we can't destroy ourselves.
 311          */
 312         INIT_WORK(&channel->work, release_channel);
 313         queue_work(vmbus_connection.work_queue, &channel->work);
 314 }
 315
 316
 317 DECLARE_COMPLETION(hv_channel_ready);
 318
 319 /*
 320  * Count initialized channels, and ensure all channels are ready when hv_vmbus
 321  * module loading completes.
 322  */
 323 static void count_hv_channel(void)
 324 {
 325         static int counter;
 326         unsigned long flags;
 327
 328         spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
 329         if (++counter == MAX_MSG_TYPES)
 330                 complete(&hv_channel_ready);
 331         spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
 332 }
 333
 334 /*
 335  * vmbus_process_rescind_offer -
 336  * Rescind the offer by initiating a device removal
 337  */
 338 static void vmbus_process_rescind_offer(struct work_struct *work)
 339 {
 340         struct vmbus_channel *channel = container_of(work,
 341                                                      struct vmbus_channel,
 342                                                      work);
 343
 344         vmbus_child_device_unregister(channel->device_obj);
 345 }
 346
 347 /*
 348  * vmbus_process_offer - Process the offer by creating a channel/device
 349  * associated with this offer
 350  */
 351 static void vmbus_process_offer(struct work_struct *work)
 352 {
 353         struct vmbus_channel *newchannel = container_of(work,
 354                                                         struct vmbus_channel,
 355                                                         work);
 356         struct vmbus_channel *channel;
 357         bool fnew = true;
 358         int ret;
 359         int cnt;
 360         unsigned long flags;
 361
 362         /* The next possible work is rescind handling */
 363         INIT_WORK(&newchannel->work, vmbus_process_rescind_offer);
 364
 365         /* Make sure this is a new offer */
 366         spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
 367
 368         list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
 369                 if (!memcmp(&channel->offermsg.offer.if_type,
 370                             &newchannel->offermsg.offer.if_type,
 371                             sizeof(struct hv_guid)) &&
 372                     !memcmp(&channel->offermsg.offer.if_instance,
 373                             &newchannel->offermsg.offer.if_instance,
 374                             sizeof(struct hv_guid))) {
 375                         fnew = false;
 376                         break;
 377                 }
 378         }
 379
 380         if (fnew)
 381                 list_add_tail(&newchannel->listentry,
 382                               &vmbus_connection.chn_list);
 383
 384         spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
 385
 386         if (!fnew) {
 387                 free_channel(newchannel);
 388                 return;
 389         }
 390
 391         /*
 392          * Start the process of binding this offer to the driver
 393          * We need to set the DeviceObject field before calling
 394          * vmbus_child_dev_add()
 395          */
 396         newchannel->device_obj = vmbus_child_device_create(
 397                 &newchannel->offermsg.offer.if_type,
 398                 &newchannel->offermsg.offer.if_instance,
 399                 newchannel);
 400
 401         /*
 402          * Add the new device to the bus. This will kick off device-driver
 403          * binding which eventually invokes the device driver's AddDevice()
 404          * method.
 405          */
 406         ret = vmbus_child_device_register(newchannel->device_obj);
 407         if (ret != 0) {
 408                 pr_err("unable to add child device object (relid %d)\n",
 409                            newchannel->offermsg.child_relid);
 410
 411                 spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
 412                 list_del(&newchannel->listentry);
 413                 spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
 414
 415                 free_channel(newchannel);
 416         } else {
 417                 /*
 418                  * This state is used to indicate a successful open
 419                  * so that when we do close the channel normally, we
 420                  * can cleanup properly
 421                  */
 422                 newchannel->state = CHANNEL_OPEN_STATE;
 423
 424                 /* Open IC channels */
 425                 for (cnt = 0; cnt < MAX_MSG_TYPES; cnt++) {
 426                         if (memcmp(&newchannel->offermsg.offer.if_type,
 427                                    &hv_cb_utils[cnt].data,
 428                                    sizeof(struct hv_guid)) == 0 &&
 429                                 vmbus_open(newchannel, 2 * PAGE_SIZE,
 430                                                  2 * PAGE_SIZE, NULL, 0,
 431                                                  hv_cb_utils[cnt].callback,
 432                                                  newchannel) == 0) {
 433                                 hv_cb_utils[cnt].channel = newchannel;
 434
 435                                 pr_info("%s\n", hv_cb_utils[cnt].log_msg);
 436
 437                                 count_hv_channel();
 438                         }
 439                 }
 440         }
 441 }
 442
 443 /*
 444  * vmbus_onoffer - Handler for channel offers from vmbus in parent partition.
 445  *
 446  * We ignore all offers except network and storage offers. For each network and
 447  * storage offers, we create a channel object and queue a work item to the
 448  * channel object to process the offer synchronously
 449  */
 450 static void vmbus_onoffer(struct vmbus_channel_message_header *hdr)
 451 {
 452         struct vmbus_channel_offer_channel *offer;
 453         struct vmbus_channel *newchannel;
 454         struct hv_guid *guidtype;
 455         struct hv_guid *guidinstance;
 456         int i;
 457         int fsupported = 0;
 458
 459         offer = (struct vmbus_channel_offer_channel *)hdr;
 460         for (i = 0; i < MAX_NUM_DEVICE_CLASSES_SUPPORTED; i++) {
 461                 if (memcmp(&offer->offer.if_type,
 462                     &gSupportedDeviceClasses[i], sizeof(struct hv_guid)) == 0) {
 463                         fsupported = 1;
 464                         break;
 465                 }
 466         }
 467
 468         if (!fsupported)
 469                 return;
 470
 471         guidtype = &offer->offer.if_type;
 472         guidinstance = &offer->offer.if_instance;
 473
 474         /* Allocate the channel object and save this offer. */
 475         newchannel = alloc_channel();
 476         if (!newchannel) {
 477                 pr_err("Unable to allocate channel object\n");
 478                 return;
 479         }
 480
 481         memcpy(&newchannel->offermsg, offer,
 482                sizeof(struct vmbus_channel_offer_channel));
 483         newchannel->monitor_grp = (u8)offer->monitorid / 32;
 484         newchannel->monitor_bit = (u8)offer->monitorid % 32;
 485
 486         /* TODO: Make sure the offer comes from our parent partition */
 487         INIT_WORK(&newchannel->work, vmbus_process_offer);
 488         queue_work(newchannel->controlwq, &newchannel->work);
 489 }
 490
 491 /*
 492  * vmbus_onoffer_rescind - Rescind offer handler.
 493  *
 494  * We queue a work item to process this offer synchronously
 495  */
 496 static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
 497 {
 498         struct vmbus_channel_rescind_offer *rescind;
 499         struct vmbus_channel *channel;
 500
 501         rescind = (struct vmbus_channel_rescind_offer *)hdr;
 502         channel = relid2channel(rescind->child_relid);
 503
 504         if (channel == NULL)
 505                 /* Just return here, no channel found */
 506                 return;
 507
 508         /* work is initialized for vmbus_process_rescind_offer() from
 509          * vmbus_process_offer() where the channel got created */
 510         queue_work(channel->controlwq, &channel->work);
 511 }
 512
 513 /*
 514  * vmbus_onoffers_delivered -
 515  * This is invoked when all offers have been delivered.
 516  *
 517  * Nothing to do here.
 518  */
 519 static void vmbus_onoffers_delivered(
 520                         struct vmbus_channel_message_header *hdr)
 521 {
 522 }
 523
 524 /*
 525  * vmbus_onopen_result - Open result handler.
 526  *
 527  * This is invoked when we received a response to our channel open request.
 528  * Find the matching request, copy the response and signal the requesting
 529  * thread.
 530  */
 531 static void vmbus_onopen_result(struct vmbus_channel_message_header *hdr)
 532 {
 533         struct vmbus_channel_open_result *result;
 534         struct vmbus_channel_msginfo *msginfo;
 535         struct vmbus_channel_message_header *requestheader;
 536         struct vmbus_channel_open_channel *openmsg;
 537         unsigned long flags;
 538
 539         result = (struct vmbus_channel_open_result *)hdr;
 540
 541         /*
 542          * Find the open msg, copy the result and signal/unblock the wait event
 543          */
 544         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 545
 546         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 547                                 msglistentry) {
 548                 requestheader =
 549                         (struct vmbus_channel_message_header *)msginfo->msg;
 550
 551                 if (requestheader->msgtype == CHANNELMSG_OPENCHANNEL) {
 552                         openmsg =
 553                         (struct vmbus_channel_open_channel *)msginfo->msg;
 554                         if (openmsg->child_relid == result->child_relid &&
 555                             openmsg->openid == result->openid) {
 556                                 memcpy(&msginfo->response.open_result,
 557                                        result,
 558                                        sizeof(struct vmbus_channel_open_result));
 559                                 msginfo->wait_condition = 1;
 560                                 wake_up(&msginfo->waitevent);
 561                                 break;
 562                         }
 563                 }
 564         }
 565         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 566 }
 567
 568 /*
 569  * vmbus_ongpadl_created - GPADL created handler.
 570  *
 571  * This is invoked when we received a response to our gpadl create request.
 572  * Find the matching request, copy the response and signal the requesting
 573  * thread.
 574  */
 575 static void vmbus_ongpadl_created(struct vmbus_channel_message_header *hdr)
 576 {
 577         struct vmbus_channel_gpadl_created *gpadlcreated;
 578         struct vmbus_channel_msginfo *msginfo;
 579         struct vmbus_channel_message_header *requestheader;
 580         struct vmbus_channel_gpadl_header *gpadlheader;
 581         unsigned long flags;
 582
 583         gpadlcreated = (struct vmbus_channel_gpadl_created *)hdr;
 584
 585         /*
 586          * Find the establish msg, copy the result and signal/unblock the wait
 587          * event
 588          */
 589         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 590
 591         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 592                                 msglistentry) {
 593                 requestheader =
 594                         (struct vmbus_channel_message_header *)msginfo->msg;
 595
 596                 if (requestheader->msgtype == CHANNELMSG_GPADL_HEADER) {
 597                         gpadlheader =
 598                         (struct vmbus_channel_gpadl_header *)requestheader;
 599
 600                         if ((gpadlcreated->child_relid ==
 601                              gpadlheader->child_relid) &&
 602                             (gpadlcreated->gpadl == gpadlheader->gpadl)) {
 603                                 memcpy(&msginfo->response.gpadl_created,
 604                                        gpadlcreated,
 605                                        sizeof(struct vmbus_channel_gpadl_created));
 606                                 msginfo->wait_condition = 1;
 607                                 wake_up(&msginfo->waitevent);
 608                                 break;
 609                         }
 610                 }
 611         }
 612         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 613 }
 614
 615 /*
 616  * vmbus_ongpadl_torndown - GPADL torndown handler.
 617  *
 618  * This is invoked when we received a response to our gpadl teardown request.
 619  * Find the matching request, copy the response and signal the requesting
 620  * thread.
 621  */
 622 static void vmbus_ongpadl_torndown(
 623                         struct vmbus_channel_message_header *hdr)
 624 {
 625         struct vmbus_channel_gpadl_torndown *gpadl_torndown;
 626         struct vmbus_channel_msginfo *msginfo;
 627         struct vmbus_channel_message_header *requestheader;
 628         struct vmbus_channel_gpadl_teardown *gpadl_teardown;
 629         unsigned long flags;
 630
 631         gpadl_torndown = (struct vmbus_channel_gpadl_torndown *)hdr;
 632
 633         /*
 634          * Find the open msg, copy the result and signal/unblock the wait event
 635          */
 636         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 637
 638         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 639                                 msglistentry) {
 640                 requestheader =
 641                         (struct vmbus_channel_message_header *)msginfo->msg;
 642
 643                 if (requestheader->msgtype == CHANNELMSG_GPADL_TEARDOWN) {
 644                         gpadl_teardown =
 645                         (struct vmbus_channel_gpadl_teardown *)requestheader;
 646
 647                         if (gpadl_torndown->gpadl == gpadl_teardown->gpadl) {
 648                                 memcpy(&msginfo->response.gpadl_torndown,
 649                                        gpadl_torndown,
 650                                        sizeof(struct vmbus_channel_gpadl_torndown));
 651                                 msginfo->wait_condition = 1;
 652                                 wake_up(&msginfo->waitevent);
 653                                 break;
 654                         }
 655                 }
 656         }
 657         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 658 }
 659
 660 /*
 661  * vmbus_onversion_response - Version response handler
 662  *
 663  * This is invoked when we received a response to our initiate contact request.
 664  * Find the matching request, copy the response and signal the requesting
 665  * thread.
 666  */
 667 static void vmbus_onversion_response(
 668                 struct vmbus_channel_message_header *hdr)
 669 {
 670         struct vmbus_channel_msginfo *msginfo;
 671         struct vmbus_channel_message_header *requestheader;
 672         struct vmbus_channel_initiate_contact *initiate;
 673         struct vmbus_channel_version_response *version_response;
 674         unsigned long flags;
 675
 676         version_response = (struct vmbus_channel_version_response *)hdr;
 677         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 678
 679         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 680                                 msglistentry) {
 681                 requestheader =
 682                         (struct vmbus_channel_message_header *)msginfo->msg;
 683
 684                 if (requestheader->msgtype ==
 685                     CHANNELMSG_INITIATE_CONTACT) {
 686                         initiate =
 687                         (struct vmbus_channel_initiate_contact *)requestheader;
 688                         memcpy(&msginfo->response.version_response,
 689                               version_response,
 690                               sizeof(struct vmbus_channel_version_response));
 691                         msginfo->wait_condition = 1;
 692                         wake_up(&msginfo->waitevent);
 693                 }
 694         }
 695         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 696 }
 697
 698 /* Channel message dispatch table */
 699 static struct vmbus_channel_message_table_entry
 700         gChannelMessageTable[CHANNELMSG_COUNT] = {
 701         {CHANNELMSG_INVALID,                    NULL},
 702         {CHANNELMSG_OFFERCHANNEL,               vmbus_onoffer},
 703         {CHANNELMSG_RESCIND_CHANNELOFFER,       vmbus_onoffer_rescind},
 704         {CHANNELMSG_REQUESTOFFERS,              NULL},
 705         {CHANNELMSG_ALLOFFERS_DELIVERED,        vmbus_onoffers_delivered},
 706         {CHANNELMSG_OPENCHANNEL,                NULL},
 707         {CHANNELMSG_OPENCHANNEL_RESULT, vmbus_onopen_result},
 708         {CHANNELMSG_CLOSECHANNEL,               NULL},
 709         {CHANNELMSG_GPADL_HEADER,               NULL},
 710         {CHANNELMSG_GPADL_BODY,         NULL},
 711         {CHANNELMSG_GPADL_CREATED,              vmbus_ongpadl_created},
 712         {CHANNELMSG_GPADL_TEARDOWN,             NULL},
 713         {CHANNELMSG_GPADL_TORNDOWN,             vmbus_ongpadl_torndown},
 714         {CHANNELMSG_RELID_RELEASED,             NULL},
 715         {CHANNELMSG_INITIATE_CONTACT,           NULL},
 716         {CHANNELMSG_VERSION_RESPONSE,           vmbus_onversion_response},
 717         {CHANNELMSG_UNLOAD,                     NULL},
 718 };
 719
 720 /*
 721  * vmbus_onmessage - Handler for channel protocol messages.
 722  *
 723  * This is invoked in the vmbus worker thread context.
 724  */
 725 void vmbus_onmessage(void *context)
 726 {
 727         struct hv_message *msg = context;
 728         struct vmbus_channel_message_header *hdr;
 729         int size;
 730
 731         hdr = (struct vmbus_channel_message_header *)msg->u.payload;
 732         size = msg->header.payload_size;
 733
 734         if (hdr->msgtype >= CHANNELMSG_COUNT) {
 735                 pr_err("Received invalid channel message type %d size %d\n",
 736                            hdr->msgtype, size);
 737                 print_hex_dump_bytes("", DUMP_PREFIX_NONE,
 738                                      (unsigned char *)msg->u.payload, size);
 739                 return;
 740         }
 741
 742         if (gChannelMessageTable[hdr->msgtype].messageHandler)
 743                 gChannelMessageTable[hdr->msgtype].messageHandler(hdr);
 744         else
 745                 pr_err("Unhandled channel message type %d\n", hdr->msgtype);
 746 }
 747
 748 /*
 749  * vmbus_request_offers - Send a request to get all our pending offers.
 750  */
 751 int vmbus_request_offers(void)
 752 {
 753         struct vmbus_channel_message_header *msg;
 754         struct vmbus_channel_msginfo *msginfo;
 755         int ret;
 756
 757         msginfo = kmalloc(sizeof(*msginfo) +
 758                           sizeof(struct vmbus_channel_message_header),
 759                           GFP_KERNEL);
 760         if (!msginfo)
 761                 return -ENOMEM;
 762
 763         init_waitqueue_head(&msginfo->waitevent);
 764
 765         msg = (struct vmbus_channel_message_header *)msginfo->msg;
 766
 767         msg->msgtype = CHANNELMSG_REQUESTOFFERS;
 768
 769
 770         ret = vmbus_post_msg(msg,
 771                                sizeof(struct vmbus_channel_message_header));
 772         if (ret != 0) {
 773                 pr_err("Unable to request offers - %d\n", ret);
 774
 775                 goto cleanup;
 776         }
 777
 778         msginfo->wait_condition = 0;
 779         wait_event_timeout(msginfo->waitevent, msginfo->wait_condition,
 780                         msecs_to_jiffies(1000));
 781         if (msginfo->wait_condition == 0) {
 782                 ret = -ETIMEDOUT;
 783                 goto cleanup;
 784         }
 785
 786
 787
 788 cleanup:
 789         kfree(msginfo);
 790
 791         return ret;
 792 }
 793
 794 /*
 795  * vmbus_release_unattached_channels - Release channels that are
 796  * unattached/unconnected ie (no drivers associated)
 797  */
 798 void vmbus_release_unattached_channels(void)
 799 {
 800         struct vmbus_channel *channel, *pos;
 801         struct vmbus_channel *start = NULL;
 802         unsigned long flags;
 803
 804         spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
 805
 806         list_for_each_entry_safe(channel, pos, &vmbus_connection.chn_list,
 807                                  listentry) {
 808                 if (channel == start)
 809                         break;
 810
 811                 if (!channel->device_obj->drv) {
 812                         list_del(&channel->listentry);
 813
 814                         pr_err("Releasing unattached device object\n");
 815
 816                         vmbus_child_device_unregister(channel->device_obj);
 817                         free_channel(channel);
 818                 } else {
 819                         if (!start)
 820                                 start = channel;
 821                 }
 822         }
 823
 824         spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
 825 }
 826
 827 /* eof */