drivers/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 <linux/hyperv.h>
  32
  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
  41 /**
  42  * vmbus_prep_negotiate_resp() - Create default response for Hyper-V Negotiate message
  43  * @icmsghdrp: Pointer to msg header structure
  44  * @icmsg_negotiate: Pointer to negotiate message structure
  45  * @buf: Raw buffer channel data
  46  *
  47  * @icmsghdrp is of type &struct icmsg_hdr.
  48  * @negop is of type &struct icmsg_negotiate.
  49  * Set up and fill in default negotiate response message. This response can
  50  * come from both the vmbus driver and the hv_utils driver. The current api
  51  * will respond properly to both Windows 2008 and Windows 2008-R2 operating
  52  * systems.
  53  *
  54  * Mainly used by Hyper-V drivers.
  55  */
  56 void vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp,
  57                                struct icmsg_negotiate *negop, u8 *buf)
  58 {
  59         if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
  60                 icmsghdrp->icmsgsize = 0x10;
  61
  62                 negop = (struct icmsg_negotiate *)&buf[
  63                         sizeof(struct vmbuspipe_hdr) +
  64                         sizeof(struct icmsg_hdr)];
  65
  66                 if (negop->icframe_vercnt == 2 &&
  67                    negop->icversion_data[1].major == 3) {
  68                         negop->icversion_data[0].major = 3;
  69                         negop->icversion_data[0].minor = 0;
  70                         negop->icversion_data[1].major = 3;
  71                         negop->icversion_data[1].minor = 0;
  72                 } else {
  73                         negop->icversion_data[0].major = 1;
  74                         negop->icversion_data[0].minor = 0;
  75                         negop->icversion_data[1].major = 1;
  76                         negop->icversion_data[1].minor = 0;
  77                 }
  78
  79                 negop->icframe_vercnt = 1;
  80                 negop->icmsg_vercnt = 1;
  81         }
  82 }
  83 EXPORT_SYMBOL_GPL(vmbus_prep_negotiate_resp);
  84
  85 /*
  86  * alloc_channel - Allocate and initialize a vmbus channel object
  87  */
  88 static struct vmbus_channel *alloc_channel(void)
  89 {
  90         struct vmbus_channel *channel;
  91
  92         channel = kzalloc(sizeof(*channel), GFP_ATOMIC);
  93         if (!channel)
  94                 return NULL;
  95
  96         spin_lock_init(&channel->inbound_lock);
  97
  98         channel->controlwq = create_workqueue("hv_vmbus_ctl");
  99         if (!channel->controlwq) {
 100                 kfree(channel);
 101                 return NULL;
 102         }
 103
 104         return channel;
 105 }
 106
 107 /*
 108  * release_hannel - Release the vmbus channel object itself
 109  */
 110 static void release_channel(struct work_struct *work)
 111 {
 112         struct vmbus_channel *channel = container_of(work,
 113                                                      struct vmbus_channel,
 114                                                      work);
 115
 116         destroy_workqueue(channel->controlwq);
 117
 118         kfree(channel);
 119 }
 120
 121 /*
 122  * free_channel - Release the resources used by the vmbus channel object
 123  */
 124 static void free_channel(struct vmbus_channel *channel)
 125 {
 126
 127         /*
 128          * We have to release the channel's workqueue/thread in the vmbus's
 129          * workqueue/thread context
 130          * ie we can't destroy ourselves.
 131          */
 132         INIT_WORK(&channel->work, release_channel);
 133         queue_work(vmbus_connection.work_queue, &channel->work);
 134 }
 135
 136
 137
 138 /*
 139  * vmbus_process_rescind_offer -
 140  * Rescind the offer by initiating a device removal
 141  */
 142 static void vmbus_process_rescind_offer(struct work_struct *work)
 143 {
 144         struct vmbus_channel *channel = container_of(work,
 145                                                      struct vmbus_channel,
 146                                                      work);
 147
 148         vmbus_device_unregister(channel->device_obj);
 149 }
 150
 151 void vmbus_free_channels(void)
 152 {
 153         struct vmbus_channel *channel;
 154
 155         list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
 156                 vmbus_device_unregister(channel->device_obj);
 157                 kfree(channel->device_obj);
 158                 free_channel(channel);
 159         }
 160 }
 161
 162 /*
 163  * vmbus_process_offer - Process the offer by creating a channel/device
 164  * associated with this offer
 165  */
 166 static void vmbus_process_offer(struct work_struct *work)
 167 {
 168         struct vmbus_channel *newchannel = container_of(work,
 169                                                         struct vmbus_channel,
 170                                                         work);
 171         struct vmbus_channel *channel;
 172         bool fnew = true;
 173         int ret;
 174         unsigned long flags;
 175
 176         /* The next possible work is rescind handling */
 177         INIT_WORK(&newchannel->work, vmbus_process_rescind_offer);
 178
 179         /* Make sure this is a new offer */
 180         spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
 181
 182         list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
 183                 if (!uuid_le_cmp(channel->offermsg.offer.if_type,
 184                         newchannel->offermsg.offer.if_type) &&
 185                         !uuid_le_cmp(channel->offermsg.offer.if_instance,
 186                                 newchannel->offermsg.offer.if_instance)) {
 187                         fnew = false;
 188                         break;
 189                 }
 190         }
 191
 192         if (fnew)
 193                 list_add_tail(&newchannel->listentry,
 194                               &vmbus_connection.chn_list);
 195
 196         spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
 197
 198         if (!fnew) {
 199                 free_channel(newchannel);
 200                 return;
 201         }
 202
 203         /*
 204          * Start the process of binding this offer to the driver
 205          * We need to set the DeviceObject field before calling
 206          * vmbus_child_dev_add()
 207          */
 208         newchannel->device_obj = vmbus_device_create(
 209                 &newchannel->offermsg.offer.if_type,
 210                 &newchannel->offermsg.offer.if_instance,
 211                 newchannel);
 212
 213         /*
 214          * Add the new device to the bus. This will kick off device-driver
 215          * binding which eventually invokes the device driver's AddDevice()
 216          * method.
 217          */
 218         ret = vmbus_device_register(newchannel->device_obj);
 219         if (ret != 0) {
 220                 pr_err("unable to add child device object (relid %d)\n",
 221                            newchannel->offermsg.child_relid);
 222
 223                 spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
 224                 list_del(&newchannel->listentry);
 225                 spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
 226                 kfree(newchannel->device_obj);
 227
 228                 free_channel(newchannel);
 229         } else {
 230                 /*
 231                  * This state is used to indicate a successful open
 232                  * so that when we do close the channel normally, we
 233                  * can cleanup properly
 234                  */
 235                 newchannel->state = CHANNEL_OPEN_STATE;
 236         }
 237 }
 238
 239 /*
 240  * vmbus_onoffer - Handler for channel offers from vmbus in parent partition.
 241  *
 242  */
 243 static void vmbus_onoffer(struct vmbus_channel_message_header *hdr)
 244 {
 245         struct vmbus_channel_offer_channel *offer;
 246         struct vmbus_channel *newchannel;
 247         uuid_le *guidtype;
 248         uuid_le *guidinstance;
 249
 250         offer = (struct vmbus_channel_offer_channel *)hdr;
 251
 252         guidtype = &offer->offer.if_type;
 253         guidinstance = &offer->offer.if_instance;
 254
 255         /* Allocate the channel object and save this offer. */
 256         newchannel = alloc_channel();
 257         if (!newchannel) {
 258                 pr_err("Unable to allocate channel object\n");
 259                 return;
 260         }
 261
 262         memcpy(&newchannel->offermsg, offer,
 263                sizeof(struct vmbus_channel_offer_channel));
 264         newchannel->monitor_grp = (u8)offer->monitorid / 32;
 265         newchannel->monitor_bit = (u8)offer->monitorid % 32;
 266
 267         INIT_WORK(&newchannel->work, vmbus_process_offer);
 268         queue_work(newchannel->controlwq, &newchannel->work);
 269 }
 270
 271 /*
 272  * vmbus_onoffer_rescind - Rescind offer handler.
 273  *
 274  * We queue a work item to process this offer synchronously
 275  */
 276 static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
 277 {
 278         struct vmbus_channel_rescind_offer *rescind;
 279         struct vmbus_channel *channel;
 280
 281         rescind = (struct vmbus_channel_rescind_offer *)hdr;
 282         channel = relid2channel(rescind->child_relid);
 283
 284         if (channel == NULL)
 285                 /* Just return here, no channel found */
 286                 return;
 287
 288         /* work is initialized for vmbus_process_rescind_offer() from
 289          * vmbus_process_offer() where the channel got created */
 290         queue_work(channel->controlwq, &channel->work);
 291 }
 292
 293 /*
 294  * vmbus_onoffers_delivered -
 295  * This is invoked when all offers have been delivered.
 296  *
 297  * Nothing to do here.
 298  */
 299 static void vmbus_onoffers_delivered(
 300                         struct vmbus_channel_message_header *hdr)
 301 {
 302 }
 303
 304 /*
 305  * vmbus_onopen_result - Open result handler.
 306  *
 307  * This is invoked when we received a response to our channel open request.
 308  * Find the matching request, copy the response and signal the requesting
 309  * thread.
 310  */
 311 static void vmbus_onopen_result(struct vmbus_channel_message_header *hdr)
 312 {
 313         struct vmbus_channel_open_result *result;
 314         struct vmbus_channel_msginfo *msginfo;
 315         struct vmbus_channel_message_header *requestheader;
 316         struct vmbus_channel_open_channel *openmsg;
 317         unsigned long flags;
 318
 319         result = (struct vmbus_channel_open_result *)hdr;
 320
 321         /*
 322          * Find the open msg, copy the result and signal/unblock the wait event
 323          */
 324         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 325
 326         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 327                                 msglistentry) {
 328                 requestheader =
 329                         (struct vmbus_channel_message_header *)msginfo->msg;
 330
 331                 if (requestheader->msgtype == CHANNELMSG_OPENCHANNEL) {
 332                         openmsg =
 333                         (struct vmbus_channel_open_channel *)msginfo->msg;
 334                         if (openmsg->child_relid == result->child_relid &&
 335                             openmsg->openid == result->openid) {
 336                                 memcpy(&msginfo->response.open_result,
 337                                        result,
 338                                        sizeof(
 339                                         struct vmbus_channel_open_result));
 340                                 complete(&msginfo->waitevent);
 341                                 break;
 342                         }
 343                 }
 344         }
 345         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 346 }
 347
 348 /*
 349  * vmbus_ongpadl_created - GPADL created handler.
 350  *
 351  * This is invoked when we received a response to our gpadl create request.
 352  * Find the matching request, copy the response and signal the requesting
 353  * thread.
 354  */
 355 static void vmbus_ongpadl_created(struct vmbus_channel_message_header *hdr)
 356 {
 357         struct vmbus_channel_gpadl_created *gpadlcreated;
 358         struct vmbus_channel_msginfo *msginfo;
 359         struct vmbus_channel_message_header *requestheader;
 360         struct vmbus_channel_gpadl_header *gpadlheader;
 361         unsigned long flags;
 362
 363         gpadlcreated = (struct vmbus_channel_gpadl_created *)hdr;
 364
 365         /*
 366          * Find the establish msg, copy the result and signal/unblock the wait
 367          * event
 368          */
 369         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 370
 371         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 372                                 msglistentry) {
 373                 requestheader =
 374                         (struct vmbus_channel_message_header *)msginfo->msg;
 375
 376                 if (requestheader->msgtype == CHANNELMSG_GPADL_HEADER) {
 377                         gpadlheader =
 378                         (struct vmbus_channel_gpadl_header *)requestheader;
 379
 380                         if ((gpadlcreated->child_relid ==
 381                              gpadlheader->child_relid) &&
 382                             (gpadlcreated->gpadl == gpadlheader->gpadl)) {
 383                                 memcpy(&msginfo->response.gpadl_created,
 384                                        gpadlcreated,
 385                                        sizeof(
 386                                         struct vmbus_channel_gpadl_created));
 387                                 complete(&msginfo->waitevent);
 388                                 break;
 389                         }
 390                 }
 391         }
 392         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 393 }
 394
 395 /*
 396  * vmbus_ongpadl_torndown - GPADL torndown handler.
 397  *
 398  * This is invoked when we received a response to our gpadl teardown request.
 399  * Find the matching request, copy the response and signal the requesting
 400  * thread.
 401  */
 402 static void vmbus_ongpadl_torndown(
 403                         struct vmbus_channel_message_header *hdr)
 404 {
 405         struct vmbus_channel_gpadl_torndown *gpadl_torndown;
 406         struct vmbus_channel_msginfo *msginfo;
 407         struct vmbus_channel_message_header *requestheader;
 408         struct vmbus_channel_gpadl_teardown *gpadl_teardown;
 409         unsigned long flags;
 410
 411         gpadl_torndown = (struct vmbus_channel_gpadl_torndown *)hdr;
 412
 413         /*
 414          * Find the open msg, copy the result and signal/unblock the wait event
 415          */
 416         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 417
 418         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 419                                 msglistentry) {
 420                 requestheader =
 421                         (struct vmbus_channel_message_header *)msginfo->msg;
 422
 423                 if (requestheader->msgtype == CHANNELMSG_GPADL_TEARDOWN) {
 424                         gpadl_teardown =
 425                         (struct vmbus_channel_gpadl_teardown *)requestheader;
 426
 427                         if (gpadl_torndown->gpadl == gpadl_teardown->gpadl) {
 428                                 memcpy(&msginfo->response.gpadl_torndown,
 429                                        gpadl_torndown,
 430                                        sizeof(
 431                                         struct vmbus_channel_gpadl_torndown));
 432                                 complete(&msginfo->waitevent);
 433                                 break;
 434                         }
 435                 }
 436         }
 437         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 438 }
 439
 440 /*
 441  * vmbus_onversion_response - Version response handler
 442  *
 443  * This is invoked when we received a response to our initiate contact request.
 444  * Find the matching request, copy the response and signal the requesting
 445  * thread.
 446  */
 447 static void vmbus_onversion_response(
 448                 struct vmbus_channel_message_header *hdr)
 449 {
 450         struct vmbus_channel_msginfo *msginfo;
 451         struct vmbus_channel_message_header *requestheader;
 452         struct vmbus_channel_initiate_contact *initiate;
 453         struct vmbus_channel_version_response *version_response;
 454         unsigned long flags;
 455
 456         version_response = (struct vmbus_channel_version_response *)hdr;
 457         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 458
 459         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 460                                 msglistentry) {
 461                 requestheader =
 462                         (struct vmbus_channel_message_header *)msginfo->msg;
 463
 464                 if (requestheader->msgtype ==
 465                     CHANNELMSG_INITIATE_CONTACT) {
 466                         initiate =
 467                         (struct vmbus_channel_initiate_contact *)requestheader;
 468                         memcpy(&msginfo->response.version_response,
 469                               version_response,
 470                               sizeof(struct vmbus_channel_version_response));
 471                         complete(&msginfo->waitevent);
 472                 }
 473         }
 474         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 475 }
 476
 477 /* Channel message dispatch table */
 478 static struct vmbus_channel_message_table_entry
 479         channel_message_table[CHANNELMSG_COUNT] = {
 480         {CHANNELMSG_INVALID,                    NULL},
 481         {CHANNELMSG_OFFERCHANNEL,               vmbus_onoffer},
 482         {CHANNELMSG_RESCIND_CHANNELOFFER,       vmbus_onoffer_rescind},
 483         {CHANNELMSG_REQUESTOFFERS,              NULL},
 484         {CHANNELMSG_ALLOFFERS_DELIVERED,        vmbus_onoffers_delivered},
 485         {CHANNELMSG_OPENCHANNEL,                NULL},
 486         {CHANNELMSG_OPENCHANNEL_RESULT, vmbus_onopen_result},
 487         {CHANNELMSG_CLOSECHANNEL,               NULL},
 488         {CHANNELMSG_GPADL_HEADER,               NULL},
 489         {CHANNELMSG_GPADL_BODY,         NULL},
 490         {CHANNELMSG_GPADL_CREATED,              vmbus_ongpadl_created},
 491         {CHANNELMSG_GPADL_TEARDOWN,             NULL},
 492         {CHANNELMSG_GPADL_TORNDOWN,             vmbus_ongpadl_torndown},
 493         {CHANNELMSG_RELID_RELEASED,             NULL},
 494         {CHANNELMSG_INITIATE_CONTACT,           NULL},
 495         {CHANNELMSG_VERSION_RESPONSE,           vmbus_onversion_response},
 496         {CHANNELMSG_UNLOAD,                     NULL},
 497 };
 498
 499 /*
 500  * vmbus_onmessage - Handler for channel protocol messages.
 501  *
 502  * This is invoked in the vmbus worker thread context.
 503  */
 504 void vmbus_onmessage(void *context)
 505 {
 506         struct hv_message *msg = context;
 507         struct vmbus_channel_message_header *hdr;
 508         int size;
 509
 510         hdr = (struct vmbus_channel_message_header *)msg->u.payload;
 511         size = msg->header.payload_size;
 512
 513         if (hdr->msgtype >= CHANNELMSG_COUNT) {
 514                 pr_err("Received invalid channel message type %d size %d\n",
 515                            hdr->msgtype, size);
 516                 print_hex_dump_bytes("", DUMP_PREFIX_NONE,
 517                                      (unsigned char *)msg->u.payload, size);
 518                 return;
 519         }
 520
 521         if (channel_message_table[hdr->msgtype].message_handler)
 522                 channel_message_table[hdr->msgtype].message_handler(hdr);
 523         else
 524                 pr_err("Unhandled channel message type %d\n", hdr->msgtype);
 525 }
 526
 527 /*
 528  * vmbus_request_offers - Send a request to get all our pending offers.
 529  */
 530 int vmbus_request_offers(void)
 531 {
 532         struct vmbus_channel_message_header *msg;
 533         struct vmbus_channel_msginfo *msginfo;
 534         int ret, t;
 535
 536         msginfo = kmalloc(sizeof(*msginfo) +
 537                           sizeof(struct vmbus_channel_message_header),
 538                           GFP_KERNEL);
 539         if (!msginfo)
 540                 return -ENOMEM;
 541
 542         init_completion(&msginfo->waitevent);
 543
 544         msg = (struct vmbus_channel_message_header *)msginfo->msg;
 545
 546         msg->msgtype = CHANNELMSG_REQUESTOFFERS;
 547
 548
 549         ret = vmbus_post_msg(msg,
 550                                sizeof(struct vmbus_channel_message_header));
 551         if (ret != 0) {
 552                 pr_err("Unable to request offers - %d\n", ret);
 553
 554                 goto cleanup;
 555         }
 556
 557         t = wait_for_completion_timeout(&msginfo->waitevent, 5*HZ);
 558         if (t == 0) {
 559                 ret = -ETIMEDOUT;
 560                 goto cleanup;
 561         }
 562
 563
 564
 565 cleanup:
 566         kfree(msginfo);
 567
 568         return ret;
 569 }
 570
 571 /* eof */