SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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 #include <linux/kernel.h>
  24 #include <linux/mm.h>
  25 #include <linux/vmalloc.h>
  26 #include "osd.h"
  27 #include "logging.h"
  28 #include "VmbusPrivate.h"
  29
  30
  31 struct VMBUS_CONNECTION gVmbusConnection = {
  32         .ConnectState           = Disconnected,
  33         .NextGpadlHandle        = ATOMIC_INIT(0xE1E10),
  34 };
  35
  36 /**
  37  * VmbusConnect - Sends a connect request on the partition service connection
  38  */
  39 int VmbusConnect(void)
  40 {
  41         int ret = 0;
  42         struct vmbus_channel_msginfo *msgInfo = NULL;
  43         struct vmbus_channel_initiate_contact *msg;
  44         unsigned long flags;
  45
  46         DPRINT_ENTER(VMBUS);
  47
  48         /* Make sure we are not connecting or connected */
  49         if (gVmbusConnection.ConnectState != Disconnected)
  50                 return -1;
  51
  52         /* Initialize the vmbus connection */
  53         gVmbusConnection.ConnectState = Connecting;
  54         gVmbusConnection.WorkQueue = create_workqueue("hv_vmbus_con");
  55         if (!gVmbusConnection.WorkQueue) {
  56                 ret = -1;
  57                 goto Cleanup;
  58         }
  59
  60         INITIALIZE_LIST_HEAD(&gVmbusConnection.ChannelMsgList);
  61         spin_lock_init(&gVmbusConnection.channelmsg_lock);
  62
  63         INITIALIZE_LIST_HEAD(&gVmbusConnection.ChannelList);
  64         spin_lock_init(&gVmbusConnection.channel_lock);
  65
  66         /*
  67          * Setup the vmbus event connection for channel interrupt
  68          * abstraction stuff
  69          */
  70         gVmbusConnection.InterruptPage = osd_PageAlloc(1);
  71         if (gVmbusConnection.InterruptPage == NULL) {
  72                 ret = -1;
  73                 goto Cleanup;
  74         }
  75
  76         gVmbusConnection.RecvInterruptPage = gVmbusConnection.InterruptPage;
  77         gVmbusConnection.SendInterruptPage =
  78                 (void *)((unsigned long)gVmbusConnection.InterruptPage +
  79                         (PAGE_SIZE >> 1));
  80
  81         /*
  82          * Setup the monitor notification facility. The 1st page for
  83          * parent->child and the 2nd page for child->parent
  84          */
  85         gVmbusConnection.MonitorPages = osd_PageAlloc(2);
  86         if (gVmbusConnection.MonitorPages == NULL) {
  87                 ret = -1;
  88                 goto Cleanup;
  89         }
  90
  91         msgInfo = kzalloc(sizeof(*msgInfo) +
  92                           sizeof(struct vmbus_channel_initiate_contact),
  93                           GFP_KERNEL);
  94         if (msgInfo == NULL) {
  95                 ret = -1;
  96                 goto Cleanup;
  97         }
  98
  99         msgInfo->WaitEvent = osd_WaitEventCreate();
 100         msg = (struct vmbus_channel_initiate_contact *)msgInfo->Msg;
 101
 102         msg->Header.MessageType = ChannelMessageInitiateContact;
 103         msg->VMBusVersionRequested = VMBUS_REVISION_NUMBER;
 104         msg->InterruptPage = virt_to_phys(gVmbusConnection.InterruptPage);
 105         msg->MonitorPage1 = virt_to_phys(gVmbusConnection.MonitorPages);
 106         msg->MonitorPage2 = virt_to_phys(
 107                         (void *)((unsigned long)gVmbusConnection.MonitorPages +
 108                                  PAGE_SIZE));
 109
 110         /*
 111          * Add to list before we send the request since we may
 112          * receive the response before returning from this routine
 113          */
 114         spin_lock_irqsave(&gVmbusConnection.channelmsg_lock, flags);
 115         INSERT_TAIL_LIST(&gVmbusConnection.ChannelMsgList,
 116                          &msgInfo->MsgListEntry);
 117         spin_unlock_irqrestore(&gVmbusConnection.channelmsg_lock, flags);
 118
 119         DPRINT_DBG(VMBUS, "Vmbus connection - interrupt pfn %llx, "
 120                    "monitor1 pfn %llx,, monitor2 pfn %llx",
 121                    msg->InterruptPage, msg->MonitorPage1, msg->MonitorPage2);
 122
 123         DPRINT_DBG(VMBUS, "Sending channel initiate msg...");
 124         ret = VmbusPostMessage(msg,
 125                                sizeof(struct vmbus_channel_initiate_contact));
 126         if (ret != 0) {
 127                 REMOVE_ENTRY_LIST(&msgInfo->MsgListEntry);
 128                 goto Cleanup;
 129         }
 130
 131         /* Wait for the connection response */
 132         osd_WaitEventWait(msgInfo->WaitEvent);
 133
 134         REMOVE_ENTRY_LIST(&msgInfo->MsgListEntry);
 135
 136         /* Check if successful */
 137         if (msgInfo->Response.VersionResponse.VersionSupported) {
 138                 DPRINT_INFO(VMBUS, "Vmbus connected!!");
 139                 gVmbusConnection.ConnectState = Connected;
 140
 141         } else {
 142                 DPRINT_ERR(VMBUS, "Vmbus connection failed!!..."
 143                            "current version (%d) not supported",
 144                            VMBUS_REVISION_NUMBER);
 145                 ret = -1;
 146                 goto Cleanup;
 147         }
 148
 149         kfree(msgInfo->WaitEvent);
 150         kfree(msgInfo);
 151         DPRINT_EXIT(VMBUS);
 152
 153         return 0;
 154
 155 Cleanup:
 156         gVmbusConnection.ConnectState = Disconnected;
 157
 158         if (gVmbusConnection.WorkQueue)
 159                 destroy_workqueue(gVmbusConnection.WorkQueue);
 160
 161         if (gVmbusConnection.InterruptPage) {
 162                 osd_PageFree(gVmbusConnection.InterruptPage, 1);
 163                 gVmbusConnection.InterruptPage = NULL;
 164         }
 165
 166         if (gVmbusConnection.MonitorPages) {
 167                 osd_PageFree(gVmbusConnection.MonitorPages, 2);
 168                 gVmbusConnection.MonitorPages = NULL;
 169         }
 170
 171         if (msgInfo) {
 172                 kfree(msgInfo->WaitEvent);
 173                 kfree(msgInfo);
 174         }
 175
 176         DPRINT_EXIT(VMBUS);
 177
 178         return ret;
 179 }
 180
 181 /**
 182  * VmbusDisconnect - Sends a disconnect request on the partition service connection
 183  */
 184 int VmbusDisconnect(void)
 185 {
 186         int ret = 0;
 187         struct vmbus_channel_message_header *msg;
 188
 189         DPRINT_ENTER(VMBUS);
 190
 191         /* Make sure we are connected */
 192         if (gVmbusConnection.ConnectState != Connected)
 193                 return -1;
 194
 195         msg = kzalloc(sizeof(struct vmbus_channel_message_header), GFP_KERNEL);
 196
 197         msg->MessageType = ChannelMessageUnload;
 198
 199         ret = VmbusPostMessage(msg,
 200                                sizeof(struct vmbus_channel_message_header));
 201         if (ret != 0)
 202                 goto Cleanup;
 203
 204         osd_PageFree(gVmbusConnection.InterruptPage, 1);
 205
 206         /* TODO: iterate thru the msg list and free up */
 207         destroy_workqueue(gVmbusConnection.WorkQueue);
 208
 209         gVmbusConnection.ConnectState = Disconnected;
 210
 211         DPRINT_INFO(VMBUS, "Vmbus disconnected!!");
 212
 213 Cleanup:
 214         kfree(msg);
 215         DPRINT_EXIT(VMBUS);
 216         return ret;
 217 }
 218
 219 /**
 220  * GetChannelFromRelId - Get the channel object given its child relative id (ie channel id)
 221  */
 222 struct vmbus_channel *GetChannelFromRelId(u32 relId)
 223 {
 224         struct vmbus_channel *channel;
 225         struct vmbus_channel *foundChannel  = NULL;
 226         LIST_ENTRY *anchor;
 227         LIST_ENTRY *curr;
 228         unsigned long flags;
 229
 230         spin_lock_irqsave(&gVmbusConnection.channel_lock, flags);
 231         ITERATE_LIST_ENTRIES(anchor, curr, &gVmbusConnection.ChannelList) {
 232                 channel = CONTAINING_RECORD(curr, struct vmbus_channel,
 233                                             ListEntry);
 234
 235                 if (channel->OfferMsg.ChildRelId == relId) {
 236                         foundChannel = channel;
 237                         break;
 238                 }
 239         }
 240         spin_unlock_irqrestore(&gVmbusConnection.channel_lock, flags);
 241
 242         return foundChannel;
 243 }
 244
 245 /**
 246  * VmbusProcessChannelEvent - Process a channel event notification
 247  */
 248 static void VmbusProcessChannelEvent(void *context)
 249 {
 250         struct vmbus_channel *channel;
 251         u32 relId = (u32)(unsigned long)context;
 252
 253         ASSERT(relId > 0);
 254
 255         /*
 256          * Find the channel based on this relid and invokes the
 257          * channel callback to process the event
 258          */
 259         channel = GetChannelFromRelId(relId);
 260
 261         if (channel) {
 262                 VmbusChannelOnChannelEvent(channel);
 263                 /*
 264                  * WorkQueueQueueWorkItem(channel->dataWorkQueue,
 265                  *                        VmbusChannelOnChannelEvent,
 266                  *                        (void*)channel);
 267                  */
 268         } else {
 269                 DPRINT_ERR(VMBUS, "channel not found for relid - %d.", relId);
 270         }
 271 }
 272
 273 /**
 274  * VmbusOnEvents - Handler for events
 275  */
 276 void VmbusOnEvents(void)
 277 {
 278         int dword;
 279         int maxdword = MAX_NUM_CHANNELS_SUPPORTED >> 5;
 280         int bit;
 281         int relid;
 282         u32 *recvInterruptPage = gVmbusConnection.RecvInterruptPage;
 283
 284         DPRINT_ENTER(VMBUS);
 285
 286         /* Check events */
 287         if (recvInterruptPage) {
 288                 for (dword = 0; dword < maxdword; dword++) {
 289                         if (recvInterruptPage[dword]) {
 290                                 for (bit = 0; bit < 32; bit++) {
 291                                         if (test_and_clear_bit(bit, (unsigned long *)&recvInterruptPage[dword])) {
 292                                                 relid = (dword << 5) + bit;
 293                                                 DPRINT_DBG(VMBUS, "event detected for relid - %d", relid);
 294
 295                                                 if (relid == 0) {
 296                                                         /* special case - vmbus channel protocol msg */
 297                                                         DPRINT_DBG(VMBUS, "invalid relid - %d", relid);
 298                                                         continue;
 299                                                 } else {
 300                                                         /* QueueWorkItem(VmbusProcessEvent, (void*)relid); */
 301                                                         /* ret = WorkQueueQueueWorkItem(gVmbusConnection.workQueue, VmbusProcessChannelEvent, (void*)relid); */
 302                                                         VmbusProcessChannelEvent((void *)(unsigned long)relid);
 303                                                 }
 304                                         }
 305                                 }
 306                         }
 307                  }
 308         }
 309         DPRINT_EXIT(VMBUS);
 310
 311         return;
 312 }
 313
 314 /**
 315  * VmbusPostMessage - Send a msg on the vmbus's message connection
 316  */
 317 int VmbusPostMessage(void *buffer, size_t bufferLen)
 318 {
 319         union hv_connection_id connId;
 320
 321         connId.Asu32 = 0;
 322         connId.u.Id = VMBUS_MESSAGE_CONNECTION_ID;
 323         return HvPostMessage(connId, 1, buffer, bufferLen);
 324 }
 325
 326 /**
 327  * VmbusSetEvent - Send an event notification to the parent
 328  */
 329 int VmbusSetEvent(u32 childRelId)
 330 {
 331         int ret = 0;
 332
 333         DPRINT_ENTER(VMBUS);
 334
 335         /* Each u32 represents 32 channels */
 336         set_bit(childRelId & 31,
 337                 (unsigned long *)gVmbusConnection.SendInterruptPage +
 338                 (childRelId >> 5));
 339
 340         ret = HvSignalEvent();
 341
 342         DPRINT_EXIT(VMBUS);
 343
 344         return ret;
 345 }