release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/staging/hv/netvsc.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 #include <linux/kernel.h>
  22 #include <linux/mm.h>
  23 #include <linux/delay.h>
  24 #include <linux/io.h>
  25 #include <linux/slab.h>
  26 #include "osd.h"
  27 #include "logging.h"
  28 #include "netvsc.h"
  29 #include "rndis_filter.h"
  30
  31
  32 /* Globals */
  33 static const char *gDriverName = "netvsc";
  34
  35 /* {F8615163-DF3E-46c5-913F-F2D2F965ED0E} */
  36 static const struct hv_guid gNetVscDeviceType = {
  37         .data = {
  38                 0x63, 0x51, 0x61, 0xF8, 0x3E, 0xDF, 0xc5, 0x46,
  39                 0x91, 0x3F, 0xF2, 0xD2, 0xF9, 0x65, 0xED, 0x0E
  40         }
  41 };
  42
  43 static int NetVscOnDeviceAdd(struct hv_device *Device, void *AdditionalInfo);
  44
  45 static int NetVscOnDeviceRemove(struct hv_device *Device);
  46
  47 static void NetVscOnCleanup(struct hv_driver *Driver);
  48
  49 static void NetVscOnChannelCallback(void *context);
  50
  51 static int NetVscInitializeSendBufferWithNetVsp(struct hv_device *Device);
  52
  53 static int NetVscInitializeReceiveBufferWithNetVsp(struct hv_device *Device);
  54
  55 static int NetVscDestroySendBuffer(struct netvsc_device *NetDevice);
  56
  57 static int NetVscDestroyReceiveBuffer(struct netvsc_device *NetDevice);
  58
  59 static int NetVscConnectToVsp(struct hv_device *Device);
  60
  61 static void NetVscOnSendCompletion(struct hv_device *Device,
  62                                    struct vmpacket_descriptor *Packet);
  63
  64 static int NetVscOnSend(struct hv_device *Device,
  65                         struct hv_netvsc_packet *Packet);
  66
  67 static void NetVscOnReceive(struct hv_device *Device,
  68                             struct vmpacket_descriptor *Packet);
  69
  70 static void NetVscOnReceiveCompletion(void *Context);
  71
  72 static void NetVscSendReceiveCompletion(struct hv_device *Device,
  73                                         u64 TransactionId);
  74
  75
  76 static struct netvsc_device *AllocNetDevice(struct hv_device *Device)
  77 {
  78         struct netvsc_device *netDevice;
  79
  80         netDevice = kzalloc(sizeof(struct netvsc_device), GFP_KERNEL);
  81         if (!netDevice)
  82                 return NULL;
  83
  84         /* Set to 2 to allow both inbound and outbound traffic */
  85         atomic_cmpxchg(&netDevice->RefCount, 0, 2);
  86
  87         netDevice->Device = Device;
  88         Device->Extension = netDevice;
  89
  90         return netDevice;
  91 }
  92
  93 static void FreeNetDevice(struct netvsc_device *Device)
  94 {
  95         WARN_ON(atomic_read(&Device->RefCount) == 0);
  96         Device->Device->Extension = NULL;
  97         kfree(Device);
  98 }
  99
 100
 101 /* Get the net device object iff exists and its refcount > 1 */
 102 static struct netvsc_device *GetOutboundNetDevice(struct hv_device *Device)
 103 {
 104         struct netvsc_device *netDevice;
 105
 106         netDevice = Device->Extension;
 107         if (netDevice && atomic_read(&netDevice->RefCount) > 1)
 108                 atomic_inc(&netDevice->RefCount);
 109         else
 110                 netDevice = NULL;
 111
 112         return netDevice;
 113 }
 114
 115 /* Get the net device object iff exists and its refcount > 0 */
 116 static struct netvsc_device *GetInboundNetDevice(struct hv_device *Device)
 117 {
 118         struct netvsc_device *netDevice;
 119
 120         netDevice = Device->Extension;
 121         if (netDevice && atomic_read(&netDevice->RefCount))
 122                 atomic_inc(&netDevice->RefCount);
 123         else
 124                 netDevice = NULL;
 125
 126         return netDevice;
 127 }
 128
 129 static void PutNetDevice(struct hv_device *Device)
 130 {
 131         struct netvsc_device *netDevice;
 132
 133         netDevice = Device->Extension;
 134         /* ASSERT(netDevice); */
 135
 136         atomic_dec(&netDevice->RefCount);
 137 }
 138
 139 static struct netvsc_device *ReleaseOutboundNetDevice(struct hv_device *Device)
 140 {
 141         struct netvsc_device *netDevice;
 142
 143         netDevice = Device->Extension;
 144         if (netDevice == NULL)
 145                 return NULL;
 146
 147         /* Busy wait until the ref drop to 2, then set it to 1 */
 148         while (atomic_cmpxchg(&netDevice->RefCount, 2, 1) != 2)
 149                 udelay(100);
 150
 151         return netDevice;
 152 }
 153
 154 static struct netvsc_device *ReleaseInboundNetDevice(struct hv_device *Device)
 155 {
 156         struct netvsc_device *netDevice;
 157
 158         netDevice = Device->Extension;
 159         if (netDevice == NULL)
 160                 return NULL;
 161
 162         /* Busy wait until the ref drop to 1, then set it to 0 */
 163         while (atomic_cmpxchg(&netDevice->RefCount, 1, 0) != 1)
 164                 udelay(100);
 165
 166         Device->Extension = NULL;
 167         return netDevice;
 168 }
 169
 170 /*
 171  * NetVscInitialize - Main entry point
 172  */
 173 int NetVscInitialize(struct hv_driver *drv)
 174 {
 175         struct netvsc_driver *driver = (struct netvsc_driver *)drv;
 176
 177         DPRINT_DBG(NETVSC, "sizeof(struct hv_netvsc_packet)=%zd, "
 178                    "sizeof(struct nvsp_message)=%zd, "
 179                    "sizeof(struct vmtransfer_page_packet_header)=%zd",
 180                    sizeof(struct hv_netvsc_packet),
 181                    sizeof(struct nvsp_message),
 182                    sizeof(struct vmtransfer_page_packet_header));
 183
 184         /* Make sure we are at least 2 pages since 1 page is used for control */
 185         /* ASSERT(driver->RingBufferSize >= (PAGE_SIZE << 1)); */
 186
 187         drv->name = gDriverName;
 188         memcpy(&drv->deviceType, &gNetVscDeviceType, sizeof(struct hv_guid));
 189
 190         /* Make sure it is set by the caller */
 191         /* ASSERT(driver->OnReceiveCallback); */
 192         /* ASSERT(driver->OnLinkStatusChanged); */
 193
 194         /* Setup the dispatch table */
 195         driver->Base.OnDeviceAdd        = NetVscOnDeviceAdd;
 196         driver->Base.OnDeviceRemove     = NetVscOnDeviceRemove;
 197         driver->Base.OnCleanup          = NetVscOnCleanup;
 198
 199         driver->OnSend                  = NetVscOnSend;
 200
 201         RndisFilterInit(driver);
 202         return 0;
 203 }
 204
 205 static int NetVscInitializeReceiveBufferWithNetVsp(struct hv_device *Device)
 206 {
 207         int ret = 0;
 208         struct netvsc_device *netDevice;
 209         struct nvsp_message *initPacket;
 210
 211         netDevice = GetOutboundNetDevice(Device);
 212         if (!netDevice) {
 213                 DPRINT_ERR(NETVSC, "unable to get net device..."
 214                            "device being destroyed?");
 215                 return -1;
 216         }
 217         /* ASSERT(netDevice->ReceiveBufferSize > 0); */
 218         /* page-size grandularity */
 219         /* ASSERT((netDevice->ReceiveBufferSize & (PAGE_SIZE - 1)) == 0); */
 220
 221         netDevice->ReceiveBuffer =
 222                 osd_PageAlloc(netDevice->ReceiveBufferSize >> PAGE_SHIFT);
 223         if (!netDevice->ReceiveBuffer) {
 224                 DPRINT_ERR(NETVSC,
 225                            "unable to allocate receive buffer of size %d",
 226                            netDevice->ReceiveBufferSize);
 227                 ret = -1;
 228                 goto Cleanup;
 229         }
 230         /* page-aligned buffer */
 231         /* ASSERT(((unsigned long)netDevice->ReceiveBuffer & (PAGE_SIZE - 1)) == */
 232         /*      0); */
 233
 234         DPRINT_INFO(NETVSC, "Establishing receive buffer's GPADL...");
 235
 236         /*
 237          * Establish the gpadl handle for this buffer on this
 238          * channel.  Note: This call uses the vmbus connection rather
 239          * than the channel to establish the gpadl handle.
 240          */
 241         ret = Device->Driver->VmbusChannelInterface.EstablishGpadl(Device,
 242                                         netDevice->ReceiveBuffer,
 243                                         netDevice->ReceiveBufferSize,
 244                                         &netDevice->ReceiveBufferGpadlHandle);
 245         if (ret != 0) {
 246                 DPRINT_ERR(NETVSC,
 247                            "unable to establish receive buffer's gpadl");
 248                 goto Cleanup;
 249         }
 250
 251         /* osd_WaitEventWait(ext->ChannelInitEvent); */
 252
 253         /* Notify the NetVsp of the gpadl handle */
 254         DPRINT_INFO(NETVSC, "Sending NvspMessage1TypeSendReceiveBuffer...");
 255
 256         initPacket = &netDevice->ChannelInitPacket;
 257
 258         memset(initPacket, 0, sizeof(struct nvsp_message));
 259
 260         initPacket->Header.MessageType = NvspMessage1TypeSendReceiveBuffer;
 261         initPacket->Messages.Version1Messages.SendReceiveBuffer.GpadlHandle = netDevice->ReceiveBufferGpadlHandle;
 262         initPacket->Messages.Version1Messages.SendReceiveBuffer.Id = NETVSC_RECEIVE_BUFFER_ID;
 263
 264         /* Send the gpadl notification request */
 265         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 266                                 initPacket,
 267                                 sizeof(struct nvsp_message),
 268                                 (unsigned long)initPacket,
 269                                 VmbusPacketTypeDataInBand,
 270                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 271         if (ret != 0) {
 272                 DPRINT_ERR(NETVSC,
 273                            "unable to send receive buffer's gpadl to netvsp");
 274                 goto Cleanup;
 275         }
 276
 277         osd_WaitEventWait(netDevice->ChannelInitEvent);
 278
 279         /* Check the response */
 280         if (initPacket->Messages.Version1Messages.SendReceiveBufferComplete.Status != NvspStatusSuccess) {
 281                 DPRINT_ERR(NETVSC, "Unable to complete receive buffer "
 282                            "initialzation with NetVsp - status %d",
 283                            initPacket->Messages.Version1Messages.SendReceiveBufferComplete.Status);
 284                 ret = -1;
 285                 goto Cleanup;
 286         }
 287
 288         /* Parse the response */
 289         /* ASSERT(netDevice->ReceiveSectionCount == 0); */
 290         /* ASSERT(netDevice->ReceiveSections == NULL); */
 291
 292         netDevice->ReceiveSectionCount = initPacket->Messages.Version1Messages.SendReceiveBufferComplete.NumSections;
 293
 294         netDevice->ReceiveSections = kmalloc(netDevice->ReceiveSectionCount * sizeof(struct nvsp_1_receive_buffer_section), GFP_KERNEL);
 295         if (netDevice->ReceiveSections == NULL) {
 296                 ret = -1;
 297                 goto Cleanup;
 298         }
 299
 300         memcpy(netDevice->ReceiveSections,
 301                 initPacket->Messages.Version1Messages.SendReceiveBufferComplete.Sections,
 302                 netDevice->ReceiveSectionCount * sizeof(struct nvsp_1_receive_buffer_section));
 303
 304         DPRINT_INFO(NETVSC, "Receive sections info (count %d, offset %d, "
 305                     "endoffset %d, suballoc size %d, num suballocs %d)",
 306                     netDevice->ReceiveSectionCount,
 307                     netDevice->ReceiveSections[0].Offset,
 308                     netDevice->ReceiveSections[0].EndOffset,
 309                     netDevice->ReceiveSections[0].SubAllocationSize,
 310                     netDevice->ReceiveSections[0].NumSubAllocations);
 311
 312         /*
 313          * For 1st release, there should only be 1 section that represents the
 314          * entire receive buffer
 315          */
 316         if (netDevice->ReceiveSectionCount != 1 ||
 317             netDevice->ReceiveSections->Offset != 0) {
 318                 ret = -1;
 319                 goto Cleanup;
 320         }
 321
 322         goto Exit;
 323
 324 Cleanup:
 325         NetVscDestroyReceiveBuffer(netDevice);
 326
 327 Exit:
 328         PutNetDevice(Device);
 329         return ret;
 330 }
 331
 332 static int NetVscInitializeSendBufferWithNetVsp(struct hv_device *Device)
 333 {
 334         int ret = 0;
 335         struct netvsc_device *netDevice;
 336         struct nvsp_message *initPacket;
 337
 338         netDevice = GetOutboundNetDevice(Device);
 339         if (!netDevice) {
 340                 DPRINT_ERR(NETVSC, "unable to get net device..."
 341                            "device being destroyed?");
 342                 return -1;
 343         }
 344         if (netDevice->SendBufferSize <= 0) {
 345                 ret = -EINVAL;
 346                 goto Cleanup;
 347         }
 348
 349         /* page-size grandularity */
 350         /* ASSERT((netDevice->SendBufferSize & (PAGE_SIZE - 1)) == 0); */
 351
 352         netDevice->SendBuffer =
 353                 osd_PageAlloc(netDevice->SendBufferSize >> PAGE_SHIFT);
 354         if (!netDevice->SendBuffer) {
 355                 DPRINT_ERR(NETVSC, "unable to allocate send buffer of size %d",
 356                            netDevice->SendBufferSize);
 357                 ret = -1;
 358                 goto Cleanup;
 359         }
 360         /* page-aligned buffer */
 361         /* ASSERT(((unsigned long)netDevice->SendBuffer & (PAGE_SIZE - 1)) == 0); */
 362
 363         DPRINT_INFO(NETVSC, "Establishing send buffer's GPADL...");
 364
 365         /*
 366          * Establish the gpadl handle for this buffer on this
 367          * channel.  Note: This call uses the vmbus connection rather
 368          * than the channel to establish the gpadl handle.
 369          */
 370         ret = Device->Driver->VmbusChannelInterface.EstablishGpadl(Device,
 371                                         netDevice->SendBuffer,
 372                                         netDevice->SendBufferSize,
 373                                         &netDevice->SendBufferGpadlHandle);
 374         if (ret != 0) {
 375                 DPRINT_ERR(NETVSC, "unable to establish send buffer's gpadl");
 376                 goto Cleanup;
 377         }
 378
 379         /* osd_WaitEventWait(ext->ChannelInitEvent); */
 380
 381         /* Notify the NetVsp of the gpadl handle */
 382         DPRINT_INFO(NETVSC, "Sending NvspMessage1TypeSendSendBuffer...");
 383
 384         initPacket = &netDevice->ChannelInitPacket;
 385
 386         memset(initPacket, 0, sizeof(struct nvsp_message));
 387
 388         initPacket->Header.MessageType = NvspMessage1TypeSendSendBuffer;
 389         initPacket->Messages.Version1Messages.SendReceiveBuffer.GpadlHandle = netDevice->SendBufferGpadlHandle;
 390         initPacket->Messages.Version1Messages.SendReceiveBuffer.Id = NETVSC_SEND_BUFFER_ID;
 391
 392         /* Send the gpadl notification request */
 393         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 394                                 initPacket, sizeof(struct nvsp_message),
 395                                 (unsigned long)initPacket,
 396                                 VmbusPacketTypeDataInBand,
 397                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 398         if (ret != 0) {
 399                 DPRINT_ERR(NETVSC,
 400                            "unable to send receive buffer's gpadl to netvsp");
 401                 goto Cleanup;
 402         }
 403
 404         osd_WaitEventWait(netDevice->ChannelInitEvent);
 405
 406         /* Check the response */
 407         if (initPacket->Messages.Version1Messages.SendSendBufferComplete.Status != NvspStatusSuccess) {
 408                 DPRINT_ERR(NETVSC, "Unable to complete send buffer "
 409                            "initialzation with NetVsp - status %d",
 410                            initPacket->Messages.Version1Messages.SendSendBufferComplete.Status);
 411                 ret = -1;
 412                 goto Cleanup;
 413         }
 414
 415         netDevice->SendSectionSize = initPacket->Messages.Version1Messages.SendSendBufferComplete.SectionSize;
 416
 417         goto Exit;
 418
 419 Cleanup:
 420         NetVscDestroySendBuffer(netDevice);
 421
 422 Exit:
 423         PutNetDevice(Device);
 424         return ret;
 425 }
 426
 427 static int NetVscDestroyReceiveBuffer(struct netvsc_device *NetDevice)
 428 {
 429         struct nvsp_message *revokePacket;
 430         int ret = 0;
 431
 432         /*
 433          * If we got a section count, it means we received a
 434          * SendReceiveBufferComplete msg (ie sent
 435          * NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
 436          * to send a revoke msg here
 437          */
 438         if (NetDevice->ReceiveSectionCount) {
 439                 DPRINT_INFO(NETVSC,
 440                             "Sending NvspMessage1TypeRevokeReceiveBuffer...");
 441
 442                 /* Send the revoke receive buffer */
 443                 revokePacket = &NetDevice->RevokePacket;
 444                 memset(revokePacket, 0, sizeof(struct nvsp_message));
 445
 446                 revokePacket->Header.MessageType = NvspMessage1TypeRevokeReceiveBuffer;
 447                 revokePacket->Messages.Version1Messages.RevokeReceiveBuffer.Id = NETVSC_RECEIVE_BUFFER_ID;
 448
 449                 ret = NetDevice->Device->Driver->VmbusChannelInterface.SendPacket(
 450                                                 NetDevice->Device,
 451                                                 revokePacket,
 452                                                 sizeof(struct nvsp_message),
 453                                                 (unsigned long)revokePacket,
 454                                                 VmbusPacketTypeDataInBand, 0);
 455                 /*
 456                  * If we failed here, we might as well return and
 457                  * have a leak rather than continue and a bugchk
 458                  */
 459                 if (ret != 0) {
 460                         DPRINT_ERR(NETVSC, "unable to send revoke receive "
 461                                    "buffer to netvsp");
 462                         return -1;
 463                 }
 464         }
 465
 466         /* Teardown the gpadl on the vsp end */
 467         if (NetDevice->ReceiveBufferGpadlHandle) {
 468                 DPRINT_INFO(NETVSC, "Tearing down receive buffer's GPADL...");
 469
 470                 ret = NetDevice->Device->Driver->VmbusChannelInterface.TeardownGpadl(
 471                                         NetDevice->Device,
 472                                         NetDevice->ReceiveBufferGpadlHandle);
 473
 474                 /* If we failed here, we might as well return and have a leak rather than continue and a bugchk */
 475                 if (ret != 0) {
 476                         DPRINT_ERR(NETVSC,
 477                                    "unable to teardown receive buffer's gpadl");
 478                         return -1;
 479                 }
 480                 NetDevice->ReceiveBufferGpadlHandle = 0;
 481         }
 482
 483         if (NetDevice->ReceiveBuffer) {
 484                 DPRINT_INFO(NETVSC, "Freeing up receive buffer...");
 485
 486                 /* Free up the receive buffer */
 487                 osd_PageFree(NetDevice->ReceiveBuffer,
 488                              NetDevice->ReceiveBufferSize >> PAGE_SHIFT);
 489                 NetDevice->ReceiveBuffer = NULL;
 490         }
 491
 492         if (NetDevice->ReceiveSections) {
 493                 NetDevice->ReceiveSectionCount = 0;
 494                 kfree(NetDevice->ReceiveSections);
 495                 NetDevice->ReceiveSections = NULL;
 496         }
 497
 498         return ret;
 499 }
 500
 501 static int NetVscDestroySendBuffer(struct netvsc_device *NetDevice)
 502 {
 503         struct nvsp_message *revokePacket;
 504         int ret = 0;
 505
 506         /*
 507          * If we got a section count, it means we received a
 508          *  SendReceiveBufferComplete msg (ie sent
 509          *  NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
 510          *  to send a revoke msg here
 511          */
 512         if (NetDevice->SendSectionSize) {
 513                 DPRINT_INFO(NETVSC,
 514                             "Sending NvspMessage1TypeRevokeSendBuffer...");
 515
 516                 /* Send the revoke send buffer */
 517                 revokePacket = &NetDevice->RevokePacket;
 518                 memset(revokePacket, 0, sizeof(struct nvsp_message));
 519
 520                 revokePacket->Header.MessageType = NvspMessage1TypeRevokeSendBuffer;
 521                 revokePacket->Messages.Version1Messages.RevokeSendBuffer.Id = NETVSC_SEND_BUFFER_ID;
 522
 523                 ret = NetDevice->Device->Driver->VmbusChannelInterface.SendPacket(NetDevice->Device,
 524                                         revokePacket,
 525                                         sizeof(struct nvsp_message),
 526                                         (unsigned long)revokePacket,
 527                                         VmbusPacketTypeDataInBand, 0);
 528                 /*
 529                  * If we failed here, we might as well return and have a leak
 530                  * rather than continue and a bugchk
 531                  */
 532                 if (ret != 0) {
 533                         DPRINT_ERR(NETVSC, "unable to send revoke send buffer "
 534                                    "to netvsp");
 535                         return -1;
 536                 }
 537         }
 538
 539         /* Teardown the gpadl on the vsp end */
 540         if (NetDevice->SendBufferGpadlHandle) {
 541                 DPRINT_INFO(NETVSC, "Tearing down send buffer's GPADL...");
 542
 543                 ret = NetDevice->Device->Driver->VmbusChannelInterface.TeardownGpadl(NetDevice->Device, NetDevice->SendBufferGpadlHandle);
 544
 545                 /*
 546                  * If we failed here, we might as well return and have a leak
 547                  * rather than continue and a bugchk
 548                  */
 549                 if (ret != 0) {
 550                         DPRINT_ERR(NETVSC, "unable to teardown send buffer's "
 551                                    "gpadl");
 552                         return -1;
 553                 }
 554                 NetDevice->SendBufferGpadlHandle = 0;
 555         }
 556
 557         if (NetDevice->SendBuffer) {
 558                 DPRINT_INFO(NETVSC, "Freeing up send buffer...");
 559
 560                 /* Free up the receive buffer */
 561                 osd_PageFree(NetDevice->SendBuffer,
 562                              NetDevice->SendBufferSize >> PAGE_SHIFT);
 563                 NetDevice->SendBuffer = NULL;
 564         }
 565
 566         return ret;
 567 }
 568
 569
 570 static int NetVscConnectToVsp(struct hv_device *Device)
 571 {
 572         int ret;
 573         struct netvsc_device *netDevice;
 574         struct nvsp_message *initPacket;
 575         int ndisVersion;
 576
 577         netDevice = GetOutboundNetDevice(Device);
 578         if (!netDevice) {
 579                 DPRINT_ERR(NETVSC, "unable to get net device..."
 580                            "device being destroyed?");
 581                 return -1;
 582         }
 583
 584         initPacket = &netDevice->ChannelInitPacket;
 585
 586         memset(initPacket, 0, sizeof(struct nvsp_message));
 587         initPacket->Header.MessageType = NvspMessageTypeInit;
 588         initPacket->Messages.InitMessages.Init.MinProtocolVersion = NVSP_MIN_PROTOCOL_VERSION;
 589         initPacket->Messages.InitMessages.Init.MaxProtocolVersion = NVSP_MAX_PROTOCOL_VERSION;
 590
 591         DPRINT_INFO(NETVSC, "Sending NvspMessageTypeInit...");
 592
 593         /* Send the init request */
 594         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 595                                 initPacket,
 596                                 sizeof(struct nvsp_message),
 597                                 (unsigned long)initPacket,
 598                                 VmbusPacketTypeDataInBand,
 599                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 600
 601         if (ret != 0) {
 602                 DPRINT_ERR(NETVSC, "unable to send NvspMessageTypeInit");
 603                 goto Cleanup;
 604         }
 605
 606         osd_WaitEventWait(netDevice->ChannelInitEvent);
 607
 608         /* Now, check the response */
 609         /* ASSERT(initPacket->Messages.InitMessages.InitComplete.MaximumMdlChainLength <= MAX_MULTIPAGE_BUFFER_COUNT); */
 610         DPRINT_INFO(NETVSC, "NvspMessageTypeInit status(%d) max mdl chain (%d)",
 611                 initPacket->Messages.InitMessages.InitComplete.Status,
 612                 initPacket->Messages.InitMessages.InitComplete.MaximumMdlChainLength);
 613
 614         if (initPacket->Messages.InitMessages.InitComplete.Status !=
 615             NvspStatusSuccess) {
 616                 DPRINT_ERR(NETVSC,
 617                         "unable to initialize with netvsp (status 0x%x)",
 618                         initPacket->Messages.InitMessages.InitComplete.Status);
 619                 ret = -1;
 620                 goto Cleanup;
 621         }
 622
 623         if (initPacket->Messages.InitMessages.InitComplete.NegotiatedProtocolVersion != NVSP_PROTOCOL_VERSION_1) {
 624                 DPRINT_ERR(NETVSC, "unable to initialize with netvsp "
 625                            "(version expected 1 got %d)",
 626                            initPacket->Messages.InitMessages.InitComplete.NegotiatedProtocolVersion);
 627                 ret = -1;
 628                 goto Cleanup;
 629         }
 630         DPRINT_INFO(NETVSC, "Sending NvspMessage1TypeSendNdisVersion...");
 631
 632         /* Send the ndis version */
 633         memset(initPacket, 0, sizeof(struct nvsp_message));
 634
 635         ndisVersion = 0x00050000;
 636
 637         initPacket->Header.MessageType = NvspMessage1TypeSendNdisVersion;
 638         initPacket->Messages.Version1Messages.SendNdisVersion.NdisMajorVersion =
 639                                 (ndisVersion & 0xFFFF0000) >> 16;
 640         initPacket->Messages.Version1Messages.SendNdisVersion.NdisMinorVersion =
 641                                 ndisVersion & 0xFFFF;
 642
 643         /* Send the init request */
 644         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 645                                         initPacket,
 646                                         sizeof(struct nvsp_message),
 647                                         (unsigned long)initPacket,
 648                                         VmbusPacketTypeDataInBand, 0);
 649         if (ret != 0) {
 650                 DPRINT_ERR(NETVSC,
 651                            "unable to send NvspMessage1TypeSendNdisVersion");
 652                 ret = -1;
 653                 goto Cleanup;
 654         }
 655         /*
 656          * BUGBUG - We have to wait for the above msg since the
 657          * netvsp uses KMCL which acknowledges packet (completion
 658          * packet) since our Vmbus always set the
 659          * VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED flag
 660          */
 661          /* osd_WaitEventWait(NetVscChannel->ChannelInitEvent); */
 662
 663         /* Post the big receive buffer to NetVSP */
 664         ret = NetVscInitializeReceiveBufferWithNetVsp(Device);
 665         if (ret == 0)
 666                 ret = NetVscInitializeSendBufferWithNetVsp(Device);
 667
 668 Cleanup:
 669         PutNetDevice(Device);
 670         return ret;
 671 }
 672
 673 static void NetVscDisconnectFromVsp(struct netvsc_device *NetDevice)
 674 {
 675         NetVscDestroyReceiveBuffer(NetDevice);
 676         NetVscDestroySendBuffer(NetDevice);
 677 }
 678
 679 /*
 680  * NetVscOnDeviceAdd - Callback when the device belonging to this driver is added
 681  */
 682 static int NetVscOnDeviceAdd(struct hv_device *Device, void *AdditionalInfo)
 683 {
 684         int ret = 0;
 685         int i;
 686         struct netvsc_device *netDevice;
 687         struct hv_netvsc_packet *packet, *pos;
 688         struct netvsc_driver *netDriver =
 689                                 (struct netvsc_driver *)Device->Driver;
 690
 691         netDevice = AllocNetDevice(Device);
 692         if (!netDevice) {
 693                 ret = -1;
 694                 goto Cleanup;
 695         }
 696
 697         DPRINT_DBG(NETVSC, "netvsc channel object allocated - %p", netDevice);
 698
 699         /* Initialize the NetVSC channel extension */
 700         netDevice->ReceiveBufferSize = NETVSC_RECEIVE_BUFFER_SIZE;
 701         spin_lock_init(&netDevice->receive_packet_list_lock);
 702
 703         netDevice->SendBufferSize = NETVSC_SEND_BUFFER_SIZE;
 704
 705         INIT_LIST_HEAD(&netDevice->ReceivePacketList);
 706
 707         for (i = 0; i < NETVSC_RECEIVE_PACKETLIST_COUNT; i++) {
 708                 packet = kzalloc(sizeof(struct hv_netvsc_packet) +
 709                                  (NETVSC_RECEIVE_SG_COUNT *
 710                                   sizeof(struct hv_page_buffer)), GFP_KERNEL);
 711                 if (!packet) {
 712                         DPRINT_DBG(NETVSC, "unable to allocate netvsc pkts "
 713                                    "for receive pool (wanted %d got %d)",
 714                                    NETVSC_RECEIVE_PACKETLIST_COUNT, i);
 715                         break;
 716                 }
 717                 list_add_tail(&packet->ListEntry,
 718                               &netDevice->ReceivePacketList);
 719         }
 720         netDevice->ChannelInitEvent = osd_WaitEventCreate();
 721         if (!netDevice->ChannelInitEvent) {
 722                 ret = -ENOMEM;
 723                 goto Cleanup;
 724         }
 725
 726         /* Open the channel */
 727         ret = Device->Driver->VmbusChannelInterface.Open(Device,
 728                                                 netDriver->RingBufferSize,
 729                                                 netDriver->RingBufferSize,
 730                                                 NULL, 0,
 731                                                 NetVscOnChannelCallback,
 732                                                 Device);
 733
 734         if (ret != 0) {
 735                 DPRINT_ERR(NETVSC, "unable to open channel: %d", ret);
 736                 ret = -1;
 737                 goto Cleanup;
 738         }
 739
 740         /* Channel is opened */
 741         DPRINT_INFO(NETVSC, "*** NetVSC channel opened successfully! ***");
 742
 743         /* Connect with the NetVsp */
 744         ret = NetVscConnectToVsp(Device);
 745         if (ret != 0) {
 746                 DPRINT_ERR(NETVSC, "unable to connect to NetVSP - %d", ret);
 747                 ret = -1;
 748                 goto Close;
 749         }
 750
 751         DPRINT_INFO(NETVSC, "*** NetVSC channel handshake result - %d ***",
 752                     ret);
 753
 754         return ret;
 755
 756 Close:
 757         /* Now, we can close the channel safely */
 758         Device->Driver->VmbusChannelInterface.Close(Device);
 759
 760 Cleanup:
 761
 762         if (netDevice) {
 763                 kfree(netDevice->ChannelInitEvent);
 764
 765                 list_for_each_entry_safe(packet, pos,
 766                                          &netDevice->ReceivePacketList,
 767                                          ListEntry) {
 768                         list_del(&packet->ListEntry);
 769                         kfree(packet);
 770                 }
 771
 772                 ReleaseOutboundNetDevice(Device);
 773                 ReleaseInboundNetDevice(Device);
 774
 775                 FreeNetDevice(netDevice);
 776         }
 777
 778         return ret;
 779 }
 780
 781 /*
 782  * NetVscOnDeviceRemove - Callback when the root bus device is removed
 783  */
 784 static int NetVscOnDeviceRemove(struct hv_device *Device)
 785 {
 786         struct netvsc_device *netDevice;
 787         struct hv_netvsc_packet *netvscPacket, *pos;
 788
 789         DPRINT_INFO(NETVSC, "Disabling outbound traffic on net device (%p)...",
 790                     Device->Extension);
 791
 792         /* Stop outbound traffic ie sends and receives completions */
 793         netDevice = ReleaseOutboundNetDevice(Device);
 794         if (!netDevice) {
 795                 DPRINT_ERR(NETVSC, "No net device present!!");
 796                 return -1;
 797         }
 798
 799         /* Wait for all send completions */
 800         while (atomic_read(&netDevice->NumOutstandingSends)) {
 801                 DPRINT_INFO(NETVSC, "waiting for %d requests to complete...",
 802                             atomic_read(&netDevice->NumOutstandingSends));
 803                 udelay(100);
 804         }
 805
 806         DPRINT_INFO(NETVSC, "Disconnecting from netvsp...");
 807
 808         NetVscDisconnectFromVsp(netDevice);
 809
 810         DPRINT_INFO(NETVSC, "Disabling inbound traffic on net device (%p)...",
 811                     Device->Extension);
 812
 813         /* Stop inbound traffic ie receives and sends completions */
 814         netDevice = ReleaseInboundNetDevice(Device);
 815
 816         /* At this point, no one should be accessing netDevice except in here */
 817         DPRINT_INFO(NETVSC, "net device (%p) safe to remove", netDevice);
 818
 819         /* Now, we can close the channel safely */
 820         Device->Driver->VmbusChannelInterface.Close(Device);
 821
 822         /* Release all resources */
 823         list_for_each_entry_safe(netvscPacket, pos,
 824                                  &netDevice->ReceivePacketList, ListEntry) {
 825                 list_del(&netvscPacket->ListEntry);
 826                 kfree(netvscPacket);
 827         }
 828
 829         kfree(netDevice->ChannelInitEvent);
 830         FreeNetDevice(netDevice);
 831         return 0;
 832 }
 833
 834 /*
 835  * NetVscOnCleanup - Perform any cleanup when the driver is removed
 836  */
 837 static void NetVscOnCleanup(struct hv_driver *drv)
 838 {
 839 }
 840
 841 static void NetVscOnSendCompletion(struct hv_device *Device,
 842                                    struct vmpacket_descriptor *Packet)
 843 {
 844         struct netvsc_device *netDevice;
 845         struct nvsp_message *nvspPacket;
 846         struct hv_netvsc_packet *nvscPacket;
 847
 848         netDevice = GetInboundNetDevice(Device);
 849         if (!netDevice) {
 850                 DPRINT_ERR(NETVSC, "unable to get net device..."
 851                            "device being destroyed?");
 852                 return;
 853         }
 854
 855         nvspPacket = (struct nvsp_message *)((unsigned long)Packet + (Packet->DataOffset8 << 3));
 856
 857         DPRINT_DBG(NETVSC, "send completion packet - type %d",
 858                    nvspPacket->Header.MessageType);
 859
 860         if ((nvspPacket->Header.MessageType == NvspMessageTypeInitComplete) ||
 861             (nvspPacket->Header.MessageType ==
 862              NvspMessage1TypeSendReceiveBufferComplete) ||
 863             (nvspPacket->Header.MessageType ==
 864              NvspMessage1TypeSendSendBufferComplete)) {
 865                 /* Copy the response back */
 866                 memcpy(&netDevice->ChannelInitPacket, nvspPacket,
 867                        sizeof(struct nvsp_message));
 868                 osd_WaitEventSet(netDevice->ChannelInitEvent);
 869         } else if (nvspPacket->Header.MessageType ==
 870                    NvspMessage1TypeSendRNDISPacketComplete) {
 871                 /* Get the send context */
 872                 nvscPacket = (struct hv_netvsc_packet *)(unsigned long)Packet->TransactionId;
 873                 /* ASSERT(nvscPacket); */
 874
 875                 /* Notify the layer above us */
 876                 nvscPacket->Completion.Send.OnSendCompletion(nvscPacket->Completion.Send.SendCompletionContext);
 877
 878                 atomic_dec(&netDevice->NumOutstandingSends);
 879         } else {
 880                 DPRINT_ERR(NETVSC, "Unknown send completion packet type - "
 881                            "%d received!!", nvspPacket->Header.MessageType);
 882         }
 883
 884         PutNetDevice(Device);
 885 }
 886
 887 static int NetVscOnSend(struct hv_device *Device,
 888                         struct hv_netvsc_packet *Packet)
 889 {
 890         struct netvsc_device *netDevice;
 891         int ret = 0;
 892
 893         struct nvsp_message sendMessage;
 894
 895         netDevice = GetOutboundNetDevice(Device);
 896         if (!netDevice) {
 897                 DPRINT_ERR(NETVSC, "net device (%p) shutting down..."
 898                            "ignoring outbound packets", netDevice);
 899                 return -2;
 900         }
 901
 902         sendMessage.Header.MessageType = NvspMessage1TypeSendRNDISPacket;
 903         if (Packet->IsDataPacket) {
 904                 /* 0 is RMC_DATA; */
 905                 sendMessage.Messages.Version1Messages.SendRNDISPacket.ChannelType = 0;
 906         } else {
 907                 /* 1 is RMC_CONTROL; */
 908                 sendMessage.Messages.Version1Messages.SendRNDISPacket.ChannelType = 1;
 909         }
 910
 911         /* Not using send buffer section */
 912         sendMessage.Messages.Version1Messages.SendRNDISPacket.SendBufferSectionIndex = 0xFFFFFFFF;
 913         sendMessage.Messages.Version1Messages.SendRNDISPacket.SendBufferSectionSize = 0;
 914
 915         if (Packet->PageBufferCount) {
 916                 ret = Device->Driver->VmbusChannelInterface.SendPacketPageBuffer(
 917                                         Device, Packet->PageBuffers,
 918                                         Packet->PageBufferCount,
 919                                         &sendMessage,
 920                                         sizeof(struct nvsp_message),
 921                                         (unsigned long)Packet);
 922         } else {
 923                 ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 924                                 &sendMessage,
 925                                 sizeof(struct nvsp_message),
 926                                 (unsigned long)Packet,
 927                                 VmbusPacketTypeDataInBand,
 928                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 929
 930         }
 931
 932         if (ret != 0)
 933                 DPRINT_ERR(NETVSC, "Unable to send packet %p ret %d",
 934                            Packet, ret);
 935
 936         atomic_inc(&netDevice->NumOutstandingSends);
 937         PutNetDevice(Device);
 938         return ret;
 939 }
 940
 941 static void NetVscOnReceive(struct hv_device *Device,
 942                             struct vmpacket_descriptor *Packet)
 943 {
 944         struct netvsc_device *netDevice;
 945         struct vmtransfer_page_packet_header *vmxferpagePacket;
 946         struct nvsp_message *nvspPacket;
 947         struct hv_netvsc_packet *netvscPacket = NULL;
 948         unsigned long start;
 949         unsigned long end, endVirtual;
 950         /* struct netvsc_driver *netvscDriver; */
 951         struct xferpage_packet *xferpagePacket = NULL;
 952         int i, j;
 953         int count = 0, bytesRemain = 0;
 954         unsigned long flags;
 955         LIST_HEAD(listHead);
 956
 957         netDevice = GetInboundNetDevice(Device);
 958         if (!netDevice) {
 959                 DPRINT_ERR(NETVSC, "unable to get net device..."
 960                            "device being destroyed?");
 961                 return;
 962         }
 963
 964         /*
 965          * All inbound packets other than send completion should be xfer page
 966          * packet
 967          */
 968         if (Packet->Type != VmbusPacketTypeDataUsingTransferPages) {
 969                 DPRINT_ERR(NETVSC, "Unknown packet type received - %d",
 970                            Packet->Type);
 971                 PutNetDevice(Device);
 972                 return;
 973         }
 974
 975         nvspPacket = (struct nvsp_message *)((unsigned long)Packet +
 976                         (Packet->DataOffset8 << 3));
 977
 978         /* Make sure this is a valid nvsp packet */
 979         if (nvspPacket->Header.MessageType != NvspMessage1TypeSendRNDISPacket) {
 980                 DPRINT_ERR(NETVSC, "Unknown nvsp packet type received - %d",
 981                            nvspPacket->Header.MessageType);
 982                 PutNetDevice(Device);
 983                 return;
 984         }
 985
 986         DPRINT_DBG(NETVSC, "NVSP packet received - type %d",
 987                    nvspPacket->Header.MessageType);
 988
 989         vmxferpagePacket = (struct vmtransfer_page_packet_header *)Packet;
 990
 991         if (vmxferpagePacket->TransferPageSetId != NETVSC_RECEIVE_BUFFER_ID) {
 992                 DPRINT_ERR(NETVSC, "Invalid xfer page set id - "
 993                            "expecting %x got %x", NETVSC_RECEIVE_BUFFER_ID,
 994                            vmxferpagePacket->TransferPageSetId);
 995                 PutNetDevice(Device);
 996                 return;
 997         }
 998
 999         DPRINT_DBG(NETVSC, "xfer page - range count %d",
1000                    vmxferpagePacket->RangeCount);
1001
1002         /*
1003          * Grab free packets (range count + 1) to represent this xfer
1004          * page packet. +1 to represent the xfer page packet itself.
1005          * We grab it here so that we know exactly how many we can
1006          * fulfil
1007          */
1008         spin_lock_irqsave(&netDevice->receive_packet_list_lock, flags);
1009         while (!list_empty(&netDevice->ReceivePacketList)) {
1010                 list_move_tail(netDevice->ReceivePacketList.next, &listHead);
1011                 if (++count == vmxferpagePacket->RangeCount + 1)
1012                         break;
1013         }
1014         spin_unlock_irqrestore(&netDevice->receive_packet_list_lock, flags);
1015
1016         /*
1017          * We need at least 2 netvsc pkts (1 to represent the xfer
1018          * page and at least 1 for the range) i.e. we can handled
1019          * some of the xfer page packet ranges...
1020          */
1021         if (count < 2) {
1022                 DPRINT_ERR(NETVSC, "Got only %d netvsc pkt...needed %d pkts. "
1023                            "Dropping this xfer page packet completely!",
1024                            count, vmxferpagePacket->RangeCount + 1);
1025
1026                 /* Return it to the freelist */
1027                 spin_lock_irqsave(&netDevice->receive_packet_list_lock, flags);
1028                 for (i = count; i != 0; i--) {
1029                         list_move_tail(listHead.next,
1030                                        &netDevice->ReceivePacketList);
1031                 }
1032                 spin_unlock_irqrestore(&netDevice->receive_packet_list_lock,
1033                                        flags);
1034
1035                 NetVscSendReceiveCompletion(Device,
1036                                             vmxferpagePacket->d.TransactionId);
1037
1038                 PutNetDevice(Device);
1039                 return;
1040         }
1041
1042         /* Remove the 1st packet to represent the xfer page packet itself */
1043         xferpagePacket = (struct xferpage_packet *)listHead.next;
1044         list_del(&xferpagePacket->ListEntry);
1045
1046         /* This is how much we can satisfy */
1047         xferpagePacket->Count = count - 1;
1048         /* ASSERT(xferpagePacket->Count > 0 && xferpagePacket->Count <= */
1049         /*      vmxferpagePacket->RangeCount); */
1050
1051         if (xferpagePacket->Count != vmxferpagePacket->RangeCount) {
1052                 DPRINT_INFO(NETVSC, "Needed %d netvsc pkts to satisy this xfer "
1053                             "page...got %d", vmxferpagePacket->RangeCount,
1054                             xferpagePacket->Count);
1055         }
1056
1057         /* Each range represents 1 RNDIS pkt that contains 1 ethernet frame */
1058         for (i = 0; i < (count - 1); i++) {
1059                 netvscPacket = (struct hv_netvsc_packet *)listHead.next;
1060                 list_del(&netvscPacket->ListEntry);
1061
1062                 /* Initialize the netvsc packet */
1063                 netvscPacket->XferPagePacket = xferpagePacket;
1064                 netvscPacket->Completion.Recv.OnReceiveCompletion =
1065                                         NetVscOnReceiveCompletion;
1066                 netvscPacket->Completion.Recv.ReceiveCompletionContext =
1067                                         netvscPacket;
1068                 netvscPacket->Device = Device;
1069                 /* Save this so that we can send it back */
1070                 netvscPacket->Completion.Recv.ReceiveCompletionTid =
1071                                         vmxferpagePacket->d.TransactionId;
1072
1073                 netvscPacket->TotalDataBufferLength =
1074                                         vmxferpagePacket->Ranges[i].ByteCount;
1075                 netvscPacket->PageBufferCount = 1;
1076
1077                 /* ASSERT(vmxferpagePacket->Ranges[i].ByteOffset + */
1078                 /*      vmxferpagePacket->Ranges[i].ByteCount < */
1079                 /*      netDevice->ReceiveBufferSize); */
1080
1081                 netvscPacket->PageBuffers[0].Length =
1082                                         vmxferpagePacket->Ranges[i].ByteCount;
1083
1084                 start = virt_to_phys((void *)((unsigned long)netDevice->ReceiveBuffer + vmxferpagePacket->Ranges[i].ByteOffset));
1085
1086                 netvscPacket->PageBuffers[0].Pfn = start >> PAGE_SHIFT;
1087                 endVirtual = (unsigned long)netDevice->ReceiveBuffer
1088                     + vmxferpagePacket->Ranges[i].ByteOffset
1089                     + vmxferpagePacket->Ranges[i].ByteCount - 1;
1090                 end = virt_to_phys((void *)endVirtual);
1091
1092                 /* Calculate the page relative offset */
1093                 netvscPacket->PageBuffers[0].Offset =
1094                         vmxferpagePacket->Ranges[i].ByteOffset & (PAGE_SIZE - 1);
1095                 if ((end >> PAGE_SHIFT) != (start >> PAGE_SHIFT)) {
1096                         /* Handle frame across multiple pages: */
1097                         netvscPacket->PageBuffers[0].Length =
1098                                 (netvscPacket->PageBuffers[0].Pfn << PAGE_SHIFT)
1099                                 + PAGE_SIZE - start;
1100                         bytesRemain = netvscPacket->TotalDataBufferLength -
1101                                         netvscPacket->PageBuffers[0].Length;
1102                         for (j = 1; j < NETVSC_PACKET_MAXPAGE; j++) {
1103                                 netvscPacket->PageBuffers[j].Offset = 0;
1104                                 if (bytesRemain <= PAGE_SIZE) {
1105                                         netvscPacket->PageBuffers[j].Length = bytesRemain;
1106                                         bytesRemain = 0;
1107                                 } else {
1108                                         netvscPacket->PageBuffers[j].Length = PAGE_SIZE;
1109                                         bytesRemain -= PAGE_SIZE;
1110                                 }
1111                                 netvscPacket->PageBuffers[j].Pfn =
1112                                     virt_to_phys((void *)(endVirtual - bytesRemain)) >> PAGE_SHIFT;
1113                                 netvscPacket->PageBufferCount++;
1114                                 if (bytesRemain == 0)
1115                                         break;
1116                         }
1117                         /* ASSERT(bytesRemain == 0); */
1118                 }
1119                 DPRINT_DBG(NETVSC, "[%d] - (abs offset %u len %u) => "
1120                            "(pfn %llx, offset %u, len %u)", i,
1121                            vmxferpagePacket->Ranges[i].ByteOffset,
1122                            vmxferpagePacket->Ranges[i].ByteCount,
1123                            netvscPacket->PageBuffers[0].Pfn,
1124                            netvscPacket->PageBuffers[0].Offset,
1125                            netvscPacket->PageBuffers[0].Length);
1126
1127                 /* Pass it to the upper layer */
1128                 ((struct netvsc_driver *)Device->Driver)->OnReceiveCallback(Device, netvscPacket);
1129
1130                 NetVscOnReceiveCompletion(netvscPacket->Completion.Recv.ReceiveCompletionContext);
1131         }
1132
1133         /* ASSERT(list_empty(&listHead)); */
1134
1135         PutNetDevice(Device);
1136 }
1137
1138 static void NetVscSendReceiveCompletion(struct hv_device *Device,
1139                                         u64 TransactionId)
1140 {
1141         struct nvsp_message recvcompMessage;
1142         int retries = 0;
1143         int ret;
1144
1145         DPRINT_DBG(NETVSC, "Sending receive completion pkt - %llx",
1146                    TransactionId);
1147
1148         recvcompMessage.Header.MessageType =
1149                                 NvspMessage1TypeSendRNDISPacketComplete;
1150
1151         recvcompMessage.Messages.Version1Messages.SendRNDISPacketComplete.Status = NvspStatusSuccess;
1152
1153 retry_send_cmplt:
1154         /* Send the completion */
1155         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
1156                                         &recvcompMessage,
1157                                         sizeof(struct nvsp_message),
1158                                         TransactionId,
1159                                         VmbusPacketTypeCompletion, 0);
1160         if (ret == 0) {
1161                 /* success */
1162                 /* no-op */
1163         } else if (ret == -1) {
1164                 /* no more room...wait a bit and attempt to retry 3 times */
1165                 retries++;
1166                 DPRINT_ERR(NETVSC, "unable to send receive completion pkt "
1167                            "(tid %llx)...retrying %d", TransactionId, retries);
1168
1169                 if (retries < 4) {
1170                         udelay(100);
1171                         goto retry_send_cmplt;
1172                 } else {
1173                         DPRINT_ERR(NETVSC, "unable to send receive completion "
1174                                   "pkt (tid %llx)...give up retrying",
1175                                   TransactionId);
1176                 }
1177         } else {
1178                 DPRINT_ERR(NETVSC, "unable to send receive completion pkt - "
1179                            "%llx", TransactionId);
1180         }
1181 }
1182
1183 /* Send a receive completion packet to RNDIS device (ie NetVsp) */
1184 static void NetVscOnReceiveCompletion(void *Context)
1185 {
1186         struct hv_netvsc_packet *packet = Context;
1187         struct hv_device *device = (struct hv_device *)packet->Device;
1188         struct netvsc_device *netDevice;
1189         u64 transactionId = 0;
1190         bool fSendReceiveComp = false;
1191         unsigned long flags;
1192
1193         /* ASSERT(packet->XferPagePacket); */
1194
1195         /*
1196          * Even though it seems logical to do a GetOutboundNetDevice() here to
1197          * send out receive completion, we are using GetInboundNetDevice()
1198          * since we may have disable outbound traffic already.
1199          */
1200         netDevice = GetInboundNetDevice(device);
1201         if (!netDevice) {
1202                 DPRINT_ERR(NETVSC, "unable to get net device..."
1203                            "device being destroyed?");
1204                 return;
1205         }
1206
1207         /* Overloading use of the lock. */
1208         spin_lock_irqsave(&netDevice->receive_packet_list_lock, flags);
1209
1210         /* ASSERT(packet->XferPagePacket->Count > 0); */
1211         packet->XferPagePacket->Count--;
1212
1213         /*
1214          * Last one in the line that represent 1 xfer page packet.
1215          * Return the xfer page packet itself to the freelist
1216          */
1217         if (packet->XferPagePacket->Count == 0) {
1218                 fSendReceiveComp = true;
1219                 transactionId = packet->Completion.Recv.ReceiveCompletionTid;
1220                 list_add_tail(&packet->XferPagePacket->ListEntry,
1221                               &netDevice->ReceivePacketList);
1222
1223         }
1224
1225         /* Put the packet back */
1226         list_add_tail(&packet->ListEntry, &netDevice->ReceivePacketList);
1227         spin_unlock_irqrestore(&netDevice->receive_packet_list_lock, flags);
1228
1229         /* Send a receive completion for the xfer page packet */
1230         if (fSendReceiveComp)
1231                 NetVscSendReceiveCompletion(device, transactionId);
1232
1233         PutNetDevice(device);
1234 }
1235
1236 static void NetVscOnChannelCallback(void *Context)
1237 {
1238         int ret;
1239         struct hv_device *device = Context;
1240         struct netvsc_device *netDevice;
1241         u32 bytesRecvd;
1242         u64 requestId;
1243         unsigned char *packet;
1244         struct vmpacket_descriptor *desc;
1245         unsigned char *buffer;
1246         int bufferlen = NETVSC_PACKET_SIZE;
1247
1248         /* ASSERT(device); */
1249
1250         packet = kzalloc(NETVSC_PACKET_SIZE * sizeof(unsigned char),
1251                          GFP_ATOMIC);
1252         if (!packet)
1253                 return;
1254         buffer = packet;
1255
1256         netDevice = GetInboundNetDevice(device);
1257         if (!netDevice) {
1258                 DPRINT_ERR(NETVSC, "net device (%p) shutting down..."
1259                            "ignoring inbound packets", netDevice);
1260                 goto out;
1261         }
1262
1263         do {
1264                 ret = device->Driver->VmbusChannelInterface.RecvPacketRaw(
1265                                                 device, buffer, bufferlen,
1266                                                 &bytesRecvd, &requestId);
1267                 if (ret == 0) {
1268                         if (bytesRecvd > 0) {
1269                                 DPRINT_DBG(NETVSC, "receive %d bytes, tid %llx",
1270                                            bytesRecvd, requestId);
1271
1272                                 desc = (struct vmpacket_descriptor *)buffer;
1273                                 switch (desc->Type) {
1274                                 case VmbusPacketTypeCompletion:
1275                                         NetVscOnSendCompletion(device, desc);
1276                                         break;
1277
1278                                 case VmbusPacketTypeDataUsingTransferPages:
1279                                         NetVscOnReceive(device, desc);
1280                                         break;
1281
1282                                 default:
1283                                         DPRINT_ERR(NETVSC,
1284                                                    "unhandled packet type %d, "
1285                                                    "tid %llx len %d\n",
1286                                                    desc->Type, requestId,
1287                                                    bytesRecvd);
1288                                         break;
1289                                 }
1290
1291                                 /* reset */
1292                                 if (bufferlen > NETVSC_PACKET_SIZE) {
1293                                         kfree(buffer);
1294                                         buffer = packet;
1295                                         bufferlen = NETVSC_PACKET_SIZE;
1296                                 }
1297                         } else {
1298                                 /* reset */
1299                                 if (bufferlen > NETVSC_PACKET_SIZE) {
1300                                         kfree(buffer);
1301                                         buffer = packet;
1302                                         bufferlen = NETVSC_PACKET_SIZE;
1303                                 }
1304
1305                                 break;
1306                         }
1307                 } else if (ret == -2) {
1308                         /* Handle large packet */
1309                         buffer = kmalloc(bytesRecvd, GFP_ATOMIC);
1310                         if (buffer == NULL) {
1311                                 /* Try again next time around */
1312                                 DPRINT_ERR(NETVSC,
1313                                            "unable to allocate buffer of size "
1314                                            "(%d)!!", bytesRecvd);
1315                                 break;
1316                         }
1317
1318                         bufferlen = bytesRecvd;
1319                 }
1320         } while (1);
1321
1322         PutNetDevice(device);
1323 out:
1324         kfree(buffer);
1325         return;
1326 }