drivers/staging/hv/Connection.c

   1 /*
   2  *
   3  * Copyright (c) 2009, Microsoft Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  16  * Place - Suite 330, Boston, MA 02111-1307 USA.
  17  *
  18  * Authors:
  19  *   Haiyang Zhang <haiyangz@microsoft.com>
  20  *   Hank Janssen  <hjanssen@microsoft.com>
  21  *
  22  */
  23
  24
  25 #include <linux/kernel.h>
  26 #include <linux/mm.h>
  27 #include <linux/vmalloc.h>
  28 #include "include/logging.h"
  29 #include "VmbusPrivate.h"
  30
  31 /* Globals */
  32
  33
  34 struct VMBUS_CONNECTION gVmbusConnection = {
  35         .ConnectState           = Disconnected,
  36         .NextGpadlHandle        = ATOMIC_INIT(0xE1E10),
  37 };
  38
  39
  40 /*++
  41
  42 Name:
  43         VmbusConnect()
  44
  45 Description:
  46         Sends a connect request on the partition service connection
  47
  48 --*/
  49 int VmbusConnect(void)
  50 {
  51         int ret=0;
  52         struct vmbus_channel_msginfo *msgInfo = NULL;
  53         VMBUS_CHANNEL_INITIATE_CONTACT *msg;
  54         unsigned long flags;
  55
  56         DPRINT_ENTER(VMBUS);
  57
  58         /* Make sure we are not connecting or connected */
  59         if (gVmbusConnection.ConnectState != Disconnected)
  60                 return -1;
  61
  62         /* Initialize the vmbus connection */
  63         gVmbusConnection.ConnectState = Connecting;
  64         gVmbusConnection.WorkQueue = create_workqueue("hv_vmbus_con");
  65         if (!gVmbusConnection.WorkQueue)
  66         {
  67                 ret = -1;
  68                 goto Cleanup;
  69         }
  70
  71         INITIALIZE_LIST_HEAD(&gVmbusConnection.ChannelMsgList);
  72         spin_lock_init(&gVmbusConnection.channelmsg_lock);
  73
  74         INITIALIZE_LIST_HEAD(&gVmbusConnection.ChannelList);
  75         spin_lock_init(&gVmbusConnection.channel_lock);
  76
  77         /*
  78          * Setup the vmbus event connection for channel interrupt
  79          * abstraction stuff
  80          */
  81         gVmbusConnection.InterruptPage = osd_PageAlloc(1);
  82         if (gVmbusConnection.InterruptPage == NULL)
  83         {
  84                 ret = -1;
  85                 goto Cleanup;
  86         }
  87
  88         gVmbusConnection.RecvInterruptPage = gVmbusConnection.InterruptPage;
  89         gVmbusConnection.SendInterruptPage = (void*)((unsigned long)gVmbusConnection.InterruptPage + (PAGE_SIZE >> 1));
  90
  91         /* Setup the monitor
  92          * notification facility. The 1st page for parent->child and
  93          * the 2nd page for child->parent
  94          */
  95         gVmbusConnection.MonitorPages = osd_PageAlloc(2);
  96         if (gVmbusConnection.MonitorPages == NULL)
  97         {
  98                 ret = -1;
  99                 goto Cleanup;
 100         }
 101
 102         msgInfo = kzalloc(sizeof(*msgInfo) + sizeof(VMBUS_CHANNEL_INITIATE_CONTACT), GFP_KERNEL);
 103         if (msgInfo == NULL)
 104         {
 105                 ret = -1;
 106                 goto Cleanup;
 107         }
 108
 109         msgInfo->WaitEvent = osd_WaitEventCreate();
 110         msg = (VMBUS_CHANNEL_INITIATE_CONTACT*)msgInfo->Msg;
 111
 112         msg->Header.MessageType = ChannelMessageInitiateContact;
 113         msg->VMBusVersionRequested = VMBUS_REVISION_NUMBER;
 114         msg->InterruptPage = virt_to_phys(gVmbusConnection.InterruptPage);
 115         msg->MonitorPage1 = virt_to_phys(gVmbusConnection.MonitorPages);
 116         msg->MonitorPage2 = virt_to_phys((void *)((unsigned long)gVmbusConnection.MonitorPages + PAGE_SIZE));
 117
 118         /*
 119          * Add to list before we send the request since we may
 120          * receive the response before returning from this routine
 121          */
 122         spin_lock_irqsave(&gVmbusConnection.channelmsg_lock, flags);
 123         INSERT_TAIL_LIST(&gVmbusConnection.ChannelMsgList, &msgInfo->MsgListEntry);
 124         spin_unlock_irqrestore(&gVmbusConnection.channelmsg_lock, flags);
 125
 126         DPRINT_DBG(VMBUS, "Vmbus connection -  interrupt pfn %llx, monitor1 pfn %llx,, monitor2 pfn %llx",
 127                 msg->InterruptPage, msg->MonitorPage1, msg->MonitorPage2);
 128
 129         DPRINT_DBG(VMBUS, "Sending channel initiate msg...");
 130
 131         ret = VmbusPostMessage(msg, sizeof(VMBUS_CHANNEL_INITIATE_CONTACT));
 132         if (ret != 0)
 133         {
 134                 REMOVE_ENTRY_LIST(&msgInfo->MsgListEntry);
 135                 goto Cleanup;
 136         }
 137
 138         /* Wait for the connection response */
 139         osd_WaitEventWait(msgInfo->WaitEvent);
 140
 141         REMOVE_ENTRY_LIST(&msgInfo->MsgListEntry);
 142
 143         /* Check if successful */
 144         if (msgInfo->Response.VersionResponse.VersionSupported)
 145         {
 146                 DPRINT_INFO(VMBUS, "Vmbus connected!!");
 147                 gVmbusConnection.ConnectState = Connected;
 148
 149         }
 150         else
 151         {
 152                 DPRINT_ERR(VMBUS, "Vmbus connection failed!!...current version (%d) not supported", VMBUS_REVISION_NUMBER);
 153                 ret = -1;
 154
 155                 goto Cleanup;
 156         }
 157
 158
 159         kfree(msgInfo->WaitEvent);
 160         kfree(msgInfo);
 161         DPRINT_EXIT(VMBUS);
 162
 163         return 0;
 164
 165 Cleanup:
 166
 167         gVmbusConnection.ConnectState = Disconnected;
 168
 169         if (gVmbusConnection.WorkQueue)
 170                 destroy_workqueue(gVmbusConnection.WorkQueue);
 171
 172         if (gVmbusConnection.InterruptPage)
 173         {
 174                 osd_PageFree(gVmbusConnection.InterruptPage, 1);
 175                 gVmbusConnection.InterruptPage = NULL;
 176         }
 177
 178         if (gVmbusConnection.MonitorPages)
 179         {
 180                 osd_PageFree(gVmbusConnection.MonitorPages, 2);
 181                 gVmbusConnection.MonitorPages = NULL;
 182         }
 183
 184         if (msgInfo)
 185         {
 186                 if (msgInfo->WaitEvent)
 187                         kfree(msgInfo->WaitEvent);
 188
 189                 kfree(msgInfo);
 190         }
 191
 192         DPRINT_EXIT(VMBUS);
 193
 194         return ret;
 195 }
 196
 197
 198 /*++
 199
 200 Name:
 201         VmbusDisconnect()
 202
 203 Description:
 204         Sends a disconnect request on the partition service connection
 205
 206 --*/
 207 int VmbusDisconnect(void)
 208 {
 209         int ret=0;
 210         VMBUS_CHANNEL_UNLOAD *msg;
 211
 212         DPRINT_ENTER(VMBUS);
 213
 214         /* Make sure we are connected */
 215         if (gVmbusConnection.ConnectState != Connected)
 216                 return -1;
 217
 218         msg = kzalloc(sizeof(VMBUS_CHANNEL_UNLOAD), GFP_KERNEL);
 219
 220         msg->MessageType = ChannelMessageUnload;
 221
 222         ret = VmbusPostMessage(msg, sizeof(VMBUS_CHANNEL_UNLOAD));
 223
 224         if (ret != 0)
 225         {
 226                 goto Cleanup;
 227         }
 228
 229         osd_PageFree(gVmbusConnection.InterruptPage, 1);
 230
 231         /* TODO: iterate thru the msg list and free up */
 232
 233         destroy_workqueue(gVmbusConnection.WorkQueue);
 234
 235         gVmbusConnection.ConnectState = Disconnected;
 236
 237         DPRINT_INFO(VMBUS, "Vmbus disconnected!!");
 238
 239 Cleanup:
 240         if (msg)
 241         {
 242                 kfree(msg);
 243         }
 244
 245         DPRINT_EXIT(VMBUS);
 246
 247         return ret;
 248 }
 249
 250
 251 /*++
 252
 253 Name:
 254         GetChannelFromRelId()
 255
 256 Description:
 257         Get the channel object given its child relative id (ie channel id)
 258
 259 --*/
 260 struct vmbus_channel *GetChannelFromRelId(u32 relId)
 261 {
 262         struct vmbus_channel *channel;
 263         struct vmbus_channel *foundChannel  = NULL;
 264         LIST_ENTRY* anchor;
 265         LIST_ENTRY* curr;
 266         unsigned long flags;
 267
 268         spin_lock_irqsave(&gVmbusConnection.channel_lock, flags);
 269         ITERATE_LIST_ENTRIES(anchor, curr, &gVmbusConnection.ChannelList)
 270         {
 271                 channel = CONTAINING_RECORD(curr, struct vmbus_channel, ListEntry);
 272
 273                 if (channel->OfferMsg.ChildRelId == relId)
 274                 {
 275                         foundChannel = channel;
 276                         break;
 277                 }
 278         }
 279         spin_unlock_irqrestore(&gVmbusConnection.channel_lock, flags);
 280
 281         return foundChannel;
 282 }
 283
 284
 285
 286 /*++
 287
 288 Name:
 289         VmbusProcessChannelEvent()
 290
 291 Description:
 292         Process a channel event notification
 293
 294 --*/
 295 static void
 296 VmbusProcessChannelEvent(
 297         void * context
 298         )
 299 {
 300         struct vmbus_channel *channel;
 301         u32 relId = (u32)(unsigned long)context;
 302
 303         ASSERT(relId > 0);
 304
 305         /*
 306          * Find the channel based on this relid and invokes the
 307          * channel callback to process the event
 308          */
 309         channel = GetChannelFromRelId(relId);
 310
 311         if (channel)
 312         {
 313                 VmbusChannelOnChannelEvent(channel);
 314                 /* WorkQueueQueueWorkItem(channel->dataWorkQueue, VmbusChannelOnChannelEvent, (void*)channel); */
 315         }
 316         else
 317         {
 318         DPRINT_ERR(VMBUS, "channel not found for relid - %d.", relId);
 319         }
 320 }
 321
 322
 323 /*++
 324
 325 Name:
 326         VmbusOnEvents()
 327
 328 Description:
 329         Handler for events
 330
 331 --*/
 332 void VmbusOnEvents(void)
 333 {
 334         int dword;
 335         /* int maxdword = PAGE_SIZE >> 3; // receive size is 1/2 page and divide that by 4 bytes */
 336         int maxdword = MAX_NUM_CHANNELS_SUPPORTED >> 5;
 337         int bit;
 338         int relid;
 339         u32* recvInterruptPage = gVmbusConnection.RecvInterruptPage;
 340         /* VMBUS_CHANNEL_MESSAGE* receiveMsg; */
 341
 342         DPRINT_ENTER(VMBUS);
 343
 344         /* Check events */
 345         if (recvInterruptPage)
 346         {
 347                 for (dword = 0; dword < maxdword; dword++)
 348                 {
 349                         if (recvInterruptPage[dword])
 350                         {
 351                                 for (bit = 0; bit < 32; bit++)
 352                                 {
 353                                         if (test_and_clear_bit(bit, (unsigned long *) &recvInterruptPage[dword]))
 354                                         {
 355                                                 relid = (dword << 5) + bit;
 356
 357                                                 DPRINT_DBG(VMBUS, "event detected for relid - %d", relid);
 358
 359                                                 if (relid == 0) /* special case - vmbus channel protocol msg */
 360                                                 {
 361                                                         DPRINT_DBG(VMBUS, "invalid relid - %d", relid);
 362
 363                                                         continue;                                               }
 364                                                 else
 365                                                 {
 366                                                         /* QueueWorkItem(VmbusProcessEvent, (void*)relid); */
 367                                                         /* ret = WorkQueueQueueWorkItem(gVmbusConnection.workQueue, VmbusProcessChannelEvent, (void*)relid); */
 368                                                         VmbusProcessChannelEvent((void*)(unsigned long)relid);
 369                                                 }
 370                                         }
 371                                 }
 372                         }
 373                  }
 374         }
 375         DPRINT_EXIT(VMBUS);
 376
 377         return;
 378 }
 379
 380 /*++
 381
 382 Name:
 383         VmbusPostMessage()
 384
 385 Description:
 386         Send a msg on the vmbus's message connection
 387
 388 --*/
 389 int VmbusPostMessage(void *buffer, size_t bufferLen)
 390 {
 391         int ret=0;
 392         HV_CONNECTION_ID connId;
 393
 394
 395         connId.Asu32 =0;
 396         connId.u.Id = VMBUS_MESSAGE_CONNECTION_ID;
 397         ret = HvPostMessage(
 398                         connId,
 399                         1,
 400                         buffer,
 401                         bufferLen);
 402
 403         return  ret;
 404 }
 405
 406 /*++
 407
 408 Name:
 409         VmbusSetEvent()
 410
 411 Description:
 412         Send an event notification to the parent
 413
 414 --*/
 415 int VmbusSetEvent(u32 childRelId)
 416 {
 417         int ret=0;
 418
 419         DPRINT_ENTER(VMBUS);
 420
 421         /* Each u32 represents 32 channels */
 422         set_bit(childRelId & 31,
 423                 (unsigned long *) gVmbusConnection.SendInterruptPage + (childRelId >> 5));
 424
 425         ret = HvSignalEvent();
 426
 427         DPRINT_EXIT(VMBUS);
 428
 429         return ret;
 430 }
 431
 432 /* EOF */