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         /* FIXME: These probably should still be tested in some way */
 192         /* ASSERT(driver->OnReceiveCallback); */
 193         /* ASSERT(driver->OnLinkStatusChanged); */
 194
 195         /* Setup the dispatch table */
 196         driver->Base.OnDeviceAdd        = NetVscOnDeviceAdd;
 197         driver->Base.OnDeviceRemove     = NetVscOnDeviceRemove;
 198         driver->Base.OnCleanup          = NetVscOnCleanup;
 199
 200         driver->OnSend                  = NetVscOnSend;
 201
 202         RndisFilterInit(driver);
 203         return 0;
 204 }
 205
 206 static int NetVscInitializeReceiveBufferWithNetVsp(struct hv_device *Device)
 207 {
 208         int ret = 0;
 209         struct netvsc_device *netDevice;
 210         struct nvsp_message *initPacket;
 211
 212         netDevice = GetOutboundNetDevice(Device);
 213         if (!netDevice) {
 214                 DPRINT_ERR(NETVSC, "unable to get net device..."
 215                            "device being destroyed?");
 216                 return -1;
 217         }
 218         /* ASSERT(netDevice->ReceiveBufferSize > 0); */
 219         /* page-size grandularity */
 220         /* ASSERT((netDevice->ReceiveBufferSize & (PAGE_SIZE - 1)) == 0); */
 221
 222         netDevice->ReceiveBuffer =
 223                 osd_PageAlloc(netDevice->ReceiveBufferSize >> PAGE_SHIFT);
 224         if (!netDevice->ReceiveBuffer) {
 225                 DPRINT_ERR(NETVSC,
 226                            "unable to allocate receive buffer of size %d",
 227                            netDevice->ReceiveBufferSize);
 228                 ret = -1;
 229                 goto Cleanup;
 230         }
 231         /* page-aligned buffer */
 232         /* ASSERT(((unsigned long)netDevice->ReceiveBuffer & (PAGE_SIZE - 1)) == */
 233         /*      0); */
 234
 235         DPRINT_INFO(NETVSC, "Establishing receive buffer's GPADL...");
 236
 237         /*
 238          * Establish the gpadl handle for this buffer on this
 239          * channel.  Note: This call uses the vmbus connection rather
 240          * than the channel to establish the gpadl handle.
 241          */
 242         ret = Device->Driver->VmbusChannelInterface.EstablishGpadl(Device,
 243                                         netDevice->ReceiveBuffer,
 244                                         netDevice->ReceiveBufferSize,
 245                                         &netDevice->ReceiveBufferGpadlHandle);
 246         if (ret != 0) {
 247                 DPRINT_ERR(NETVSC,
 248                            "unable to establish receive buffer's gpadl");
 249                 goto Cleanup;
 250         }
 251
 252         /* osd_WaitEventWait(ext->ChannelInitEvent); */
 253
 254         /* Notify the NetVsp of the gpadl handle */
 255         DPRINT_INFO(NETVSC, "Sending NvspMessage1TypeSendReceiveBuffer...");
 256
 257         initPacket = &netDevice->ChannelInitPacket;
 258
 259         memset(initPacket, 0, sizeof(struct nvsp_message));
 260
 261         initPacket->Header.MessageType = NvspMessage1TypeSendReceiveBuffer;
 262         initPacket->Messages.Version1Messages.SendReceiveBuffer.GpadlHandle = netDevice->ReceiveBufferGpadlHandle;
 263         initPacket->Messages.Version1Messages.SendReceiveBuffer.Id = NETVSC_RECEIVE_BUFFER_ID;
 264
 265         /* Send the gpadl notification request */
 266         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 267                                 initPacket,
 268                                 sizeof(struct nvsp_message),
 269                                 (unsigned long)initPacket,
 270                                 VmbusPacketTypeDataInBand,
 271                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 272         if (ret != 0) {
 273                 DPRINT_ERR(NETVSC,
 274                            "unable to send receive buffer's gpadl to netvsp");
 275                 goto Cleanup;
 276         }
 277
 278         osd_WaitEventWait(netDevice->ChannelInitEvent);
 279
 280         /* Check the response */
 281         if (initPacket->Messages.Version1Messages.SendReceiveBufferComplete.Status != NvspStatusSuccess) {
 282                 DPRINT_ERR(NETVSC, "Unable to complete receive buffer "
 283                            "initialzation with NetVsp - status %d",
 284                            initPacket->Messages.Version1Messages.SendReceiveBufferComplete.Status);
 285                 ret = -1;
 286                 goto Cleanup;
 287         }
 288
 289         /* Parse the response */
 290         /* ASSERT(netDevice->ReceiveSectionCount == 0); */
 291         /* ASSERT(netDevice->ReceiveSections == NULL); */
 292
 293         netDevice->ReceiveSectionCount = initPacket->Messages.Version1Messages.SendReceiveBufferComplete.NumSections;
 294
 295         netDevice->ReceiveSections = kmalloc(netDevice->ReceiveSectionCount * sizeof(struct nvsp_1_receive_buffer_section), GFP_KERNEL);
 296         if (netDevice->ReceiveSections == NULL) {
 297                 ret = -1;
 298                 goto Cleanup;
 299         }
 300
 301         memcpy(netDevice->ReceiveSections,
 302                 initPacket->Messages.Version1Messages.SendReceiveBufferComplete.Sections,
 303                 netDevice->ReceiveSectionCount * sizeof(struct nvsp_1_receive_buffer_section));
 304
 305         DPRINT_INFO(NETVSC, "Receive sections info (count %d, offset %d, "
 306                     "endoffset %d, suballoc size %d, num suballocs %d)",
 307                     netDevice->ReceiveSectionCount,
 308                     netDevice->ReceiveSections[0].Offset,
 309                     netDevice->ReceiveSections[0].EndOffset,
 310                     netDevice->ReceiveSections[0].SubAllocationSize,
 311                     netDevice->ReceiveSections[0].NumSubAllocations);
 312
 313         /*
 314          * For 1st release, there should only be 1 section that represents the
 315          * entire receive buffer
 316          */
 317         if (netDevice->ReceiveSectionCount != 1 ||
 318             netDevice->ReceiveSections->Offset != 0) {
 319                 ret = -1;
 320                 goto Cleanup;
 321         }
 322
 323         goto Exit;
 324
 325 Cleanup:
 326         NetVscDestroyReceiveBuffer(netDevice);
 327
 328 Exit:
 329         PutNetDevice(Device);
 330         return ret;
 331 }
 332
 333 static int NetVscInitializeSendBufferWithNetVsp(struct hv_device *Device)
 334 {
 335         int ret = 0;
 336         struct netvsc_device *netDevice;
 337         struct nvsp_message *initPacket;
 338
 339         netDevice = GetOutboundNetDevice(Device);
 340         if (!netDevice) {
 341                 DPRINT_ERR(NETVSC, "unable to get net device..."
 342                            "device being destroyed?");
 343                 return -1;
 344         }
 345         if (netDevice->SendBufferSize <= 0) {
 346                 ret = -EINVAL;
 347                 goto Cleanup;
 348         }
 349
 350         /* page-size grandularity */
 351         /* ASSERT((netDevice->SendBufferSize & (PAGE_SIZE - 1)) == 0); */
 352
 353         netDevice->SendBuffer =
 354                 osd_PageAlloc(netDevice->SendBufferSize >> PAGE_SHIFT);
 355         if (!netDevice->SendBuffer) {
 356                 DPRINT_ERR(NETVSC, "unable to allocate send buffer of size %d",
 357                            netDevice->SendBufferSize);
 358                 ret = -1;
 359                 goto Cleanup;
 360         }
 361         /* page-aligned buffer */
 362         /* ASSERT(((unsigned long)netDevice->SendBuffer & (PAGE_SIZE - 1)) == 0); */
 363
 364         DPRINT_INFO(NETVSC, "Establishing send buffer's GPADL...");
 365
 366         /*
 367          * Establish the gpadl handle for this buffer on this
 368          * channel.  Note: This call uses the vmbus connection rather
 369          * than the channel to establish the gpadl handle.
 370          */
 371         ret = Device->Driver->VmbusChannelInterface.EstablishGpadl(Device,
 372                                         netDevice->SendBuffer,
 373                                         netDevice->SendBufferSize,
 374                                         &netDevice->SendBufferGpadlHandle);
 375         if (ret != 0) {
 376                 DPRINT_ERR(NETVSC, "unable to establish send buffer's gpadl");
 377                 goto Cleanup;
 378         }
 379
 380         /* osd_WaitEventWait(ext->ChannelInitEvent); */
 381
 382         /* Notify the NetVsp of the gpadl handle */
 383         DPRINT_INFO(NETVSC, "Sending NvspMessage1TypeSendSendBuffer...");
 384
 385         initPacket = &netDevice->ChannelInitPacket;
 386
 387         memset(initPacket, 0, sizeof(struct nvsp_message));
 388
 389         initPacket->Header.MessageType = NvspMessage1TypeSendSendBuffer;
 390         initPacket->Messages.Version1Messages.SendReceiveBuffer.GpadlHandle = netDevice->SendBufferGpadlHandle;
 391         initPacket->Messages.Version1Messages.SendReceiveBuffer.Id = NETVSC_SEND_BUFFER_ID;
 392
 393         /* Send the gpadl notification request */
 394         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 395                                 initPacket, sizeof(struct nvsp_message),
 396                                 (unsigned long)initPacket,
 397                                 VmbusPacketTypeDataInBand,
 398                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 399         if (ret != 0) {
 400                 DPRINT_ERR(NETVSC,
 401                            "unable to send receive buffer's gpadl to netvsp");
 402                 goto Cleanup;
 403         }
 404
 405         osd_WaitEventWait(netDevice->ChannelInitEvent);
 406
 407         /* Check the response */
 408         if (initPacket->Messages.Version1Messages.SendSendBufferComplete.Status != NvspStatusSuccess) {
 409                 DPRINT_ERR(NETVSC, "Unable to complete send buffer "
 410                            "initialzation with NetVsp - status %d",
 411                            initPacket->Messages.Version1Messages.SendSendBufferComplete.Status);
 412                 ret = -1;
 413                 goto Cleanup;
 414         }
 415
 416         netDevice->SendSectionSize = initPacket->Messages.Version1Messages.SendSendBufferComplete.SectionSize;
 417
 418         goto Exit;
 419
 420 Cleanup:
 421         NetVscDestroySendBuffer(netDevice);
 422
 423 Exit:
 424         PutNetDevice(Device);
 425         return ret;
 426 }
 427
 428 static int NetVscDestroyReceiveBuffer(struct netvsc_device *NetDevice)
 429 {
 430         struct nvsp_message *revokePacket;
 431         int ret = 0;
 432
 433         /*
 434          * If we got a section count, it means we received a
 435          * SendReceiveBufferComplete msg (ie sent
 436          * NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
 437          * to send a revoke msg here
 438          */
 439         if (NetDevice->ReceiveSectionCount) {
 440                 DPRINT_INFO(NETVSC,
 441                             "Sending NvspMessage1TypeRevokeReceiveBuffer...");
 442
 443                 /* Send the revoke receive buffer */
 444                 revokePacket = &NetDevice->RevokePacket;
 445                 memset(revokePacket, 0, sizeof(struct nvsp_message));
 446
 447                 revokePacket->Header.MessageType = NvspMessage1TypeRevokeReceiveBuffer;
 448                 revokePacket->Messages.Version1Messages.RevokeReceiveBuffer.Id = NETVSC_RECEIVE_BUFFER_ID;
 449
 450                 ret = NetDevice->Device->Driver->VmbusChannelInterface.SendPacket(
 451                                                 NetDevice->Device,
 452                                                 revokePacket,
 453                                                 sizeof(struct nvsp_message),
 454                                                 (unsigned long)revokePacket,
 455                                                 VmbusPacketTypeDataInBand, 0);
 456                 /*
 457                  * If we failed here, we might as well return and
 458                  * have a leak rather than continue and a bugchk
 459                  */
 460                 if (ret != 0) {
 461                         DPRINT_ERR(NETVSC, "unable to send revoke receive "
 462                                    "buffer to netvsp");
 463                         return -1;
 464                 }
 465         }
 466
 467         /* Teardown the gpadl on the vsp end */
 468         if (NetDevice->ReceiveBufferGpadlHandle) {
 469                 DPRINT_INFO(NETVSC, "Tearing down receive buffer's GPADL...");
 470
 471                 ret = NetDevice->Device->Driver->VmbusChannelInterface.TeardownGpadl(
 472                                         NetDevice->Device,
 473                                         NetDevice->ReceiveBufferGpadlHandle);
 474
 475                 /* If we failed here, we might as well return and have a leak rather than continue and a bugchk */
 476                 if (ret != 0) {
 477                         DPRINT_ERR(NETVSC,
 478                                    "unable to teardown receive buffer's gpadl");
 479                         return -1;
 480                 }
 481                 NetDevice->ReceiveBufferGpadlHandle = 0;
 482         }
 483
 484         if (NetDevice->ReceiveBuffer) {
 485                 DPRINT_INFO(NETVSC, "Freeing up receive buffer...");
 486
 487                 /* Free up the receive buffer */
 488                 osd_PageFree(NetDevice->ReceiveBuffer,
 489                              NetDevice->ReceiveBufferSize >> PAGE_SHIFT);
 490                 NetDevice->ReceiveBuffer = NULL;
 491         }
 492
 493         if (NetDevice->ReceiveSections) {
 494                 NetDevice->ReceiveSectionCount = 0;
 495                 kfree(NetDevice->ReceiveSections);
 496                 NetDevice->ReceiveSections = NULL;
 497         }
 498
 499         return ret;
 500 }
 501
 502 static int NetVscDestroySendBuffer(struct netvsc_device *NetDevice)
 503 {
 504         struct nvsp_message *revokePacket;
 505         int ret = 0;
 506
 507         /*
 508          * If we got a section count, it means we received a
 509          *  SendReceiveBufferComplete msg (ie sent
 510          *  NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
 511          *  to send a revoke msg here
 512          */
 513         if (NetDevice->SendSectionSize) {
 514                 DPRINT_INFO(NETVSC,
 515                             "Sending NvspMessage1TypeRevokeSendBuffer...");
 516
 517                 /* Send the revoke send buffer */
 518                 revokePacket = &NetDevice->RevokePacket;
 519                 memset(revokePacket, 0, sizeof(struct nvsp_message));
 520
 521                 revokePacket->Header.MessageType = NvspMessage1TypeRevokeSendBuffer;
 522                 revokePacket->Messages.Version1Messages.RevokeSendBuffer.Id = NETVSC_SEND_BUFFER_ID;
 523
 524                 ret = NetDevice->Device->Driver->VmbusChannelInterface.SendPacket(NetDevice->Device,
 525                                         revokePacket,
 526                                         sizeof(struct nvsp_message),
 527                                         (unsigned long)revokePacket,
 528                                         VmbusPacketTypeDataInBand, 0);
 529                 /*
 530                  * If we failed here, we might as well return and have a leak
 531                  * rather than continue and a bugchk
 532                  */
 533                 if (ret != 0) {
 534                         DPRINT_ERR(NETVSC, "unable to send revoke send buffer "
 535                                    "to netvsp");
 536                         return -1;
 537                 }
 538         }
 539
 540         /* Teardown the gpadl on the vsp end */
 541         if (NetDevice->SendBufferGpadlHandle) {
 542                 DPRINT_INFO(NETVSC, "Tearing down send buffer's GPADL...");
 543
 544                 ret = NetDevice->Device->Driver->VmbusChannelInterface.TeardownGpadl(NetDevice->Device, NetDevice->SendBufferGpadlHandle);
 545
 546                 /*
 547                  * If we failed here, we might as well return and have a leak
 548                  * rather than continue and a bugchk
 549                  */
 550                 if (ret != 0) {
 551                         DPRINT_ERR(NETVSC, "unable to teardown send buffer's "
 552                                    "gpadl");
 553                         return -1;
 554                 }
 555                 NetDevice->SendBufferGpadlHandle = 0;
 556         }
 557
 558         if (NetDevice->SendBuffer) {
 559                 DPRINT_INFO(NETVSC, "Freeing up send buffer...");
 560
 561                 /* Free up the receive buffer */
 562                 osd_PageFree(NetDevice->SendBuffer,
 563                              NetDevice->SendBufferSize >> PAGE_SHIFT);
 564                 NetDevice->SendBuffer = NULL;
 565         }
 566
 567         return ret;
 568 }
 569
 570
 571 static int NetVscConnectToVsp(struct hv_device *Device)
 572 {
 573         int ret;
 574         struct netvsc_device *netDevice;
 575         struct nvsp_message *initPacket;
 576         int ndisVersion;
 577
 578         netDevice = GetOutboundNetDevice(Device);
 579         if (!netDevice) {
 580                 DPRINT_ERR(NETVSC, "unable to get net device..."
 581                            "device being destroyed?");
 582                 return -1;
 583         }
 584
 585         initPacket = &netDevice->ChannelInitPacket;
 586
 587         memset(initPacket, 0, sizeof(struct nvsp_message));
 588         initPacket->Header.MessageType = NvspMessageTypeInit;
 589         initPacket->Messages.InitMessages.Init.MinProtocolVersion = NVSP_MIN_PROTOCOL_VERSION;
 590         initPacket->Messages.InitMessages.Init.MaxProtocolVersion = NVSP_MAX_PROTOCOL_VERSION;
 591
 592         DPRINT_INFO(NETVSC, "Sending NvspMessageTypeInit...");
 593
 594         /* Send the init request */
 595         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 596                                 initPacket,
 597                                 sizeof(struct nvsp_message),
 598                                 (unsigned long)initPacket,
 599                                 VmbusPacketTypeDataInBand,
 600                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 601
 602         if (ret != 0) {
 603                 DPRINT_ERR(NETVSC, "unable to send NvspMessageTypeInit");
 604                 goto Cleanup;
 605         }
 606
 607         osd_WaitEventWait(netDevice->ChannelInitEvent);
 608
 609         /* Now, check the response */
 610         /* ASSERT(initPacket->Messages.InitMessages.InitComplete.MaximumMdlChainLength <= MAX_MULTIPAGE_BUFFER_COUNT); */
 611         DPRINT_INFO(NETVSC, "NvspMessageTypeInit status(%d) max mdl chain (%d)",
 612                 initPacket->Messages.InitMessages.InitComplete.Status,
 613                 initPacket->Messages.InitMessages.InitComplete.MaximumMdlChainLength);
 614
 615         if (initPacket->Messages.InitMessages.InitComplete.Status !=
 616             NvspStatusSuccess) {
 617                 DPRINT_ERR(NETVSC,
 618                         "unable to initialize with netvsp (status 0x%x)",
 619                         initPacket->Messages.InitMessages.InitComplete.Status);
 620                 ret = -1;
 621                 goto Cleanup;
 622         }
 623
 624         if (initPacket->Messages.InitMessages.InitComplete.NegotiatedProtocolVersion != NVSP_PROTOCOL_VERSION_1) {
 625                 DPRINT_ERR(NETVSC, "unable to initialize with netvsp "
 626                            "(version expected 1 got %d)",
 627                            initPacket->Messages.InitMessages.InitComplete.NegotiatedProtocolVersion);
 628                 ret = -1;
 629                 goto Cleanup;
 630         }
 631         DPRINT_INFO(NETVSC, "Sending NvspMessage1TypeSendNdisVersion...");
 632
 633         /* Send the ndis version */
 634         memset(initPacket, 0, sizeof(struct nvsp_message));
 635
 636         ndisVersion = 0x00050000;
 637
 638         initPacket->Header.MessageType = NvspMessage1TypeSendNdisVersion;
 639         initPacket->Messages.Version1Messages.SendNdisVersion.NdisMajorVersion =
 640                                 (ndisVersion & 0xFFFF0000) >> 16;
 641         initPacket->Messages.Version1Messages.SendNdisVersion.NdisMinorVersion =
 642                                 ndisVersion & 0xFFFF;
 643
 644         /* Send the init request */
 645         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 646                                         initPacket,
 647                                         sizeof(struct nvsp_message),
 648                                         (unsigned long)initPacket,
 649                                         VmbusPacketTypeDataInBand, 0);
 650         if (ret != 0) {
 651                 DPRINT_ERR(NETVSC,
 652                            "unable to send NvspMessage1TypeSendNdisVersion");
 653                 ret = -1;
 654                 goto Cleanup;
 655         }
 656         /*
 657          * BUGBUG - We have to wait for the above msg since the
 658          * netvsp uses KMCL which acknowledges packet (completion
 659          * packet) since our Vmbus always set the
 660          * VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED flag
 661          */
 662          /* osd_WaitEventWait(NetVscChannel->ChannelInitEvent); */
 663
 664         /* Post the big receive buffer to NetVSP */
 665         ret = NetVscInitializeReceiveBufferWithNetVsp(Device);
 666         if (ret == 0)
 667                 ret = NetVscInitializeSendBufferWithNetVsp(Device);
 668
 669 Cleanup:
 670         PutNetDevice(Device);
 671         return ret;
 672 }
 673
 674 static void NetVscDisconnectFromVsp(struct netvsc_device *NetDevice)
 675 {
 676         NetVscDestroyReceiveBuffer(NetDevice);
 677         NetVscDestroySendBuffer(NetDevice);
 678 }
 679
 680 /*
 681  * NetVscOnDeviceAdd - Callback when the device belonging to this driver is added
 682  */
 683 static int NetVscOnDeviceAdd(struct hv_device *Device, void *AdditionalInfo)
 684 {
 685         int ret = 0;
 686         int i;
 687         struct netvsc_device *netDevice;
 688         struct hv_netvsc_packet *packet, *pos;
 689         struct netvsc_driver *netDriver =
 690                                 (struct netvsc_driver *)Device->Driver;
 691
 692         netDevice = AllocNetDevice(Device);
 693         if (!netDevice) {
 694                 ret = -1;
 695                 goto Cleanup;
 696         }
 697
 698         DPRINT_DBG(NETVSC, "netvsc channel object allocated - %p", netDevice);
 699
 700         /* Initialize the NetVSC channel extension */
 701         netDevice->ReceiveBufferSize = NETVSC_RECEIVE_BUFFER_SIZE;
 702         spin_lock_init(&netDevice->receive_packet_list_lock);
 703
 704         netDevice->SendBufferSize = NETVSC_SEND_BUFFER_SIZE;
 705
 706         INIT_LIST_HEAD(&netDevice->ReceivePacketList);
 707
 708         for (i = 0; i < NETVSC_RECEIVE_PACKETLIST_COUNT; i++) {
 709                 packet = kzalloc(sizeof(struct hv_netvsc_packet) +
 710                                  (NETVSC_RECEIVE_SG_COUNT *
 711                                   sizeof(struct hv_page_buffer)), GFP_KERNEL);
 712                 if (!packet) {
 713                         DPRINT_DBG(NETVSC, "unable to allocate netvsc pkts "
 714                                    "for receive pool (wanted %d got %d)",
 715                                    NETVSC_RECEIVE_PACKETLIST_COUNT, i);
 716                         break;
 717                 }
 718                 list_add_tail(&packet->ListEntry,
 719                               &netDevice->ReceivePacketList);
 720         }
 721         netDevice->ChannelInitEvent = osd_WaitEventCreate();
 722         if (!netDevice->ChannelInitEvent) {
 723                 ret = -ENOMEM;
 724                 goto Cleanup;
 725         }
 726
 727         /* Open the channel */
 728         ret = Device->Driver->VmbusChannelInterface.Open(Device,
 729                                                 netDriver->RingBufferSize,
 730                                                 netDriver->RingBufferSize,
 731                                                 NULL, 0,
 732                                                 NetVscOnChannelCallback,
 733                                                 Device);
 734
 735         if (ret != 0) {
 736                 DPRINT_ERR(NETVSC, "unable to open channel: %d", ret);
 737                 ret = -1;
 738                 goto Cleanup;
 739         }
 740
 741         /* Channel is opened */
 742         DPRINT_INFO(NETVSC, "*** NetVSC channel opened successfully! ***");
 743
 744         /* Connect with the NetVsp */
 745         ret = NetVscConnectToVsp(Device);
 746         if (ret != 0) {
 747                 DPRINT_ERR(NETVSC, "unable to connect to NetVSP - %d", ret);
 748                 ret = -1;
 749                 goto Close;
 750         }
 751
 752         DPRINT_INFO(NETVSC, "*** NetVSC channel handshake result - %d ***",
 753                     ret);
 754
 755         return ret;
 756
 757 Close:
 758         /* Now, we can close the channel safely */
 759         Device->Driver->VmbusChannelInterface.Close(Device);
 760
 761 Cleanup:
 762
 763         if (netDevice) {
 764                 kfree(netDevice->ChannelInitEvent);
 765
 766                 list_for_each_entry_safe(packet, pos,
 767                                          &netDevice->ReceivePacketList,
 768                                          ListEntry) {
 769                         list_del(&packet->ListEntry);
 770                         kfree(packet);
 771                 }
 772
 773                 ReleaseOutboundNetDevice(Device);
 774                 ReleaseInboundNetDevice(Device);
 775
 776                 FreeNetDevice(netDevice);
 777         }
 778
 779         return ret;
 780 }
 781
 782 /*
 783  * NetVscOnDeviceRemove - Callback when the root bus device is removed
 784  */
 785 static int NetVscOnDeviceRemove(struct hv_device *Device)
 786 {
 787         struct netvsc_device *netDevice;
 788         struct hv_netvsc_packet *netvscPacket, *pos;
 789
 790         DPRINT_INFO(NETVSC, "Disabling outbound traffic on net device (%p)...",
 791                     Device->Extension);
 792
 793         /* Stop outbound traffic ie sends and receives completions */
 794         netDevice = ReleaseOutboundNetDevice(Device);
 795         if (!netDevice) {
 796                 DPRINT_ERR(NETVSC, "No net device present!!");
 797                 return -1;
 798         }
 799
 800         /* Wait for all send completions */
 801         while (atomic_read(&netDevice->NumOutstandingSends)) {
 802                 DPRINT_INFO(NETVSC, "waiting for %d requests to complete...",
 803                             atomic_read(&netDevice->NumOutstandingSends));
 804                 udelay(100);
 805         }
 806
 807         DPRINT_INFO(NETVSC, "Disconnecting from netvsp...");
 808
 809         NetVscDisconnectFromVsp(netDevice);
 810
 811         DPRINT_INFO(NETVSC, "Disabling inbound traffic on net device (%p)...",
 812                     Device->Extension);
 813
 814         /* Stop inbound traffic ie receives and sends completions */
 815         netDevice = ReleaseInboundNetDevice(Device);
 816
 817         /* At this point, no one should be accessing netDevice except in here */
 818         DPRINT_INFO(NETVSC, "net device (%p) safe to remove", netDevice);
 819
 820         /* Now, we can close the channel safely */
 821         Device->Driver->VmbusChannelInterface.Close(Device);
 822
 823         /* Release all resources */
 824         list_for_each_entry_safe(netvscPacket, pos,
 825                                  &netDevice->ReceivePacketList, ListEntry) {
 826                 list_del(&netvscPacket->ListEntry);
 827                 kfree(netvscPacket);
 828         }
 829
 830         kfree(netDevice->ChannelInitEvent);
 831         FreeNetDevice(netDevice);
 832         return 0;
 833 }
 834
 835 /*
 836  * NetVscOnCleanup - Perform any cleanup when the driver is removed
 837  */
 838 static void NetVscOnCleanup(struct hv_driver *drv)
 839 {
 840 }
 841
 842 static void NetVscOnSendCompletion(struct hv_device *Device,
 843                                    struct vmpacket_descriptor *Packet)
 844 {
 845         struct netvsc_device *netDevice;
 846         struct nvsp_message *nvspPacket;
 847         struct hv_netvsc_packet *nvscPacket;
 848
 849         netDevice = GetInboundNetDevice(Device);
 850         if (!netDevice) {
 851                 DPRINT_ERR(NETVSC, "unable to get net device..."
 852                            "device being destroyed?");
 853                 return;
 854         }
 855
 856         nvspPacket = (struct nvsp_message *)((unsigned long)Packet + (Packet->DataOffset8 << 3));
 857
 858         DPRINT_DBG(NETVSC, "send completion packet - type %d",
 859                    nvspPacket->Header.MessageType);
 860
 861         if ((nvspPacket->Header.MessageType == NvspMessageTypeInitComplete) ||
 862             (nvspPacket->Header.MessageType ==
 863              NvspMessage1TypeSendReceiveBufferComplete) ||
 864             (nvspPacket->Header.MessageType ==
 865              NvspMessage1TypeSendSendBufferComplete)) {
 866                 /* Copy the response back */
 867                 memcpy(&netDevice->ChannelInitPacket, nvspPacket,
 868                        sizeof(struct nvsp_message));
 869                 osd_WaitEventSet(netDevice->ChannelInitEvent);
 870         } else if (nvspPacket->Header.MessageType ==
 871                    NvspMessage1TypeSendRNDISPacketComplete) {
 872                 /* Get the send context */
 873                 nvscPacket = (struct hv_netvsc_packet *)(unsigned long)Packet->TransactionId;
 874                 /* ASSERT(nvscPacket); */
 875
 876                 /* Notify the layer above us */
 877                 nvscPacket->Completion.Send.OnSendCompletion(nvscPacket->Completion.Send.SendCompletionContext);
 878
 879                 atomic_dec(&netDevice->NumOutstandingSends);
 880         } else {
 881                 DPRINT_ERR(NETVSC, "Unknown send completion packet type - "
 882                            "%d received!!", nvspPacket->Header.MessageType);
 883         }
 884
 885         PutNetDevice(Device);
 886 }
 887
 888 static int NetVscOnSend(struct hv_device *Device,
 889                         struct hv_netvsc_packet *Packet)
 890 {
 891         struct netvsc_device *netDevice;
 892         int ret = 0;
 893
 894         struct nvsp_message sendMessage;
 895
 896         netDevice = GetOutboundNetDevice(Device);
 897         if (!netDevice) {
 898                 DPRINT_ERR(NETVSC, "net device (%p) shutting down..."
 899                            "ignoring outbound packets", netDevice);
 900                 return -2;
 901         }
 902
 903         sendMessage.Header.MessageType = NvspMessage1TypeSendRNDISPacket;
 904         if (Packet->IsDataPacket) {
 905                 /* 0 is RMC_DATA; */
 906                 sendMessage.Messages.Version1Messages.SendRNDISPacket.ChannelType = 0;
 907         } else {
 908                 /* 1 is RMC_CONTROL; */
 909                 sendMessage.Messages.Version1Messages.SendRNDISPacket.ChannelType = 1;
 910         }
 911
 912         /* Not using send buffer section */
 913         sendMessage.Messages.Version1Messages.SendRNDISPacket.SendBufferSectionIndex = 0xFFFFFFFF;
 914         sendMessage.Messages.Version1Messages.SendRNDISPacket.SendBufferSectionSize = 0;
 915
 916         if (Packet->PageBufferCount) {
 917                 ret = Device->Driver->VmbusChannelInterface.SendPacketPageBuffer(
 918                                         Device, Packet->PageBuffers,
 919                                         Packet->PageBufferCount,
 920                                         &sendMessage,
 921                                         sizeof(struct nvsp_message),
 922                                         (unsigned long)Packet);
 923         } else {
 924                 ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 925                                 &sendMessage,
 926                                 sizeof(struct nvsp_message),
 927                                 (unsigned long)Packet,
 928                                 VmbusPacketTypeDataInBand,
 929                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 930
 931         }
 932
 933         if (ret != 0)
 934                 DPRINT_ERR(NETVSC, "Unable to send packet %p ret %d",
 935                            Packet, ret);
 936
 937         atomic_inc(&netDevice->NumOutstandingSends);
 938         PutNetDevice(Device);
 939         return ret;
 940 }
 941
 942 static void NetVscOnReceive(struct hv_device *Device,
 943                             struct vmpacket_descriptor *Packet)
 944 {
 945         struct netvsc_device *netDevice;
 946         struct vmtransfer_page_packet_header *vmxferpagePacket;
 947         struct nvsp_message *nvspPacket;
 948         struct hv_netvsc_packet *netvscPacket = NULL;
 949         unsigned long start;
 950         unsigned long end, endVirtual;
 951         /* struct netvsc_driver *netvscDriver; */
 952         struct xferpage_packet *xferpagePacket = NULL;
 953         int i, j;
 954         int count = 0, bytesRemain = 0;
 955         unsigned long flags;
 956         LIST_HEAD(listHead);
 957
 958         netDevice = GetInboundNetDevice(Device);
 959         if (!netDevice) {
 960                 DPRINT_ERR(NETVSC, "unable to get net device..."
 961                            "device being destroyed?");
 962                 return;
 963         }
 964
 965         /*
 966          * All inbound packets other than send completion should be xfer page
 967          * packet
 968          */
 969         if (Packet->Type != VmbusPacketTypeDataUsingTransferPages) {
 970                 DPRINT_ERR(NETVSC, "Unknown packet type received - %d",
 971                            Packet->Type);
 972                 PutNetDevice(Device);
 973                 return;
 974         }
 975
 976         nvspPacket = (struct nvsp_message *)((unsigned long)Packet +
 977                         (Packet->DataOffset8 << 3));
 978
 979         /* Make sure this is a valid nvsp packet */
 980         if (nvspPacket->Header.MessageType != NvspMessage1TypeSendRNDISPacket) {
 981                 DPRINT_ERR(NETVSC, "Unknown nvsp packet type received - %d",
 982                            nvspPacket->Header.MessageType);
 983                 PutNetDevice(Device);
 984                 return;
 985         }
 986
 987         DPRINT_DBG(NETVSC, "NVSP packet received - type %d",
 988                    nvspPacket->Header.MessageType);
 989
 990         vmxferpagePacket = (struct vmtransfer_page_packet_header *)Packet;
 991
 992         if (vmxferpagePacket->TransferPageSetId != NETVSC_RECEIVE_BUFFER_ID) {
 993                 DPRINT_ERR(NETVSC, "Invalid xfer page set id - "
 994                            "expecting %x got %x", NETVSC_RECEIVE_BUFFER_ID,
 995                            vmxferpagePacket->TransferPageSetId);
 996                 PutNetDevice(Device);
 997                 return;
 998         }
 999
1000         DPRINT_DBG(NETVSC, "xfer page - range count %d",
1001                    vmxferpagePacket->RangeCount);
1002
1003         /*
1004          * Grab free packets (range count + 1) to represent this xfer
1005          * page packet. +1 to represent the xfer page packet itself.
1006          * We grab it here so that we know exactly how many we can
1007          * fulfil
1008          */
1009         spin_lock_irqsave(&netDevice->receive_packet_list_lock, flags);
1010         while (!list_empty(&netDevice->ReceivePacketList)) {
1011                 list_move_tail(netDevice->ReceivePacketList.next, &listHead);
1012                 if (++count == vmxferpagePacket->RangeCount + 1)
1013                         break;
1014         }
1015         spin_unlock_irqrestore(&netDevice->receive_packet_list_lock, flags);
1016
1017         /*
1018          * We need at least 2 netvsc pkts (1 to represent the xfer
1019          * page and at least 1 for the range) i.e. we can handled
1020          * some of the xfer page packet ranges...
1021          */
1022         if (count < 2) {
1023                 DPRINT_ERR(NETVSC, "Got only %d netvsc pkt...needed %d pkts. "
1024                            "Dropping this xfer page packet completely!",
1025                            count, vmxferpagePacket->RangeCount + 1);
1026
1027                 /* Return it to the freelist */
1028                 spin_lock_irqsave(&netDevice->receive_packet_list_lock, flags);
1029                 for (i = count; i != 0; i--) {
1030                         list_move_tail(listHead.next,
1031                                        &netDevice->ReceivePacketList);
1032                 }
1033                 spin_unlock_irqrestore(&netDevice->receive_packet_list_lock,
1034                                        flags);
1035
1036                 NetVscSendReceiveCompletion(Device,
1037                                             vmxferpagePacket->d.TransactionId);
1038
1039                 PutNetDevice(Device);
1040                 return;
1041         }
1042
1043         /* Remove the 1st packet to represent the xfer page packet itself */
1044         xferpagePacket = (struct xferpage_packet *)listHead.next;
1045         list_del(&xferpagePacket->ListEntry);
1046
1047         /* This is how much we can satisfy */
1048         xferpagePacket->Count = count - 1;
1049         /* ASSERT(xferpagePacket->Count > 0 && xferpagePacket->Count <= */
1050         /*      vmxferpagePacket->RangeCount); */
1051
1052         if (xferpagePacket->Count != vmxferpagePacket->RangeCount) {
1053                 DPRINT_INFO(NETVSC, "Needed %d netvsc pkts to satisy this xfer "
1054                             "page...got %d", vmxferpagePacket->RangeCount,
1055                             xferpagePacket->Count);
1056         }
1057
1058         /* Each range represents 1 RNDIS pkt that contains 1 ethernet frame */
1059         for (i = 0; i < (count - 1); i++) {
1060                 netvscPacket = (struct hv_netvsc_packet *)listHead.next;
1061                 list_del(&netvscPacket->ListEntry);
1062
1063                 /* Initialize the netvsc packet */
1064                 netvscPacket->XferPagePacket = xferpagePacket;
1065                 netvscPacket->Completion.Recv.OnReceiveCompletion =
1066                                         NetVscOnReceiveCompletion;
1067                 netvscPacket->Completion.Recv.ReceiveCompletionContext =
1068                                         netvscPacket;
1069                 netvscPacket->Device = Device;
1070                 /* Save this so that we can send it back */
1071                 netvscPacket->Completion.Recv.ReceiveCompletionTid =
1072                                         vmxferpagePacket->d.TransactionId;
1073
1074                 netvscPacket->TotalDataBufferLength =
1075                                         vmxferpagePacket->Ranges[i].ByteCount;
1076                 netvscPacket->PageBufferCount = 1;
1077
1078                 /* ASSERT(vmxferpagePacket->Ranges[i].ByteOffset + */
1079                 /*      vmxferpagePacket->Ranges[i].ByteCount < */
1080                 /*      netDevice->ReceiveBufferSize); */
1081
1082                 netvscPacket->PageBuffers[0].Length =
1083                                         vmxferpagePacket->Ranges[i].ByteCount;
1084
1085                 start = virt_to_phys((void *)((unsigned long)netDevice->ReceiveBuffer + vmxferpagePacket->Ranges[i].ByteOffset));
1086
1087                 netvscPacket->PageBuffers[0].Pfn = start >> PAGE_SHIFT;
1088                 endVirtual = (unsigned long)netDevice->ReceiveBuffer
1089                     + vmxferpagePacket->Ranges[i].ByteOffset
1090                     + vmxferpagePacket->Ranges[i].ByteCount - 1;
1091                 end = virt_to_phys((void *)endVirtual);
1092
1093                 /* Calculate the page relative offset */
1094                 netvscPacket->PageBuffers[0].Offset =
1095                         vmxferpagePacket->Ranges[i].ByteOffset & (PAGE_SIZE - 1);
1096                 if ((end >> PAGE_SHIFT) != (start >> PAGE_SHIFT)) {
1097                         /* Handle frame across multiple pages: */
1098                         netvscPacket->PageBuffers[0].Length =
1099                                 (netvscPacket->PageBuffers[0].Pfn << PAGE_SHIFT)
1100                                 + PAGE_SIZE - start;
1101                         bytesRemain = netvscPacket->TotalDataBufferLength -
1102                                         netvscPacket->PageBuffers[0].Length;
1103                         for (j = 1; j < NETVSC_PACKET_MAXPAGE; j++) {
1104                                 netvscPacket->PageBuffers[j].Offset = 0;
1105                                 if (bytesRemain <= PAGE_SIZE) {
1106                                         netvscPacket->PageBuffers[j].Length = bytesRemain;
1107                                         bytesRemain = 0;
1108                                 } else {
1109                                         netvscPacket->PageBuffers[j].Length = PAGE_SIZE;
1110                                         bytesRemain -= PAGE_SIZE;
1111                                 }
1112                                 netvscPacket->PageBuffers[j].Pfn =
1113                                     virt_to_phys((void *)(endVirtual - bytesRemain)) >> PAGE_SHIFT;
1114                                 netvscPacket->PageBufferCount++;
1115                                 if (bytesRemain == 0)
1116                                         break;
1117                         }
1118                         /* ASSERT(bytesRemain == 0); */
1119                 }
1120                 DPRINT_DBG(NETVSC, "[%d] - (abs offset %u len %u) => "
1121                            "(pfn %llx, offset %u, len %u)", i,
1122                            vmxferpagePacket->Ranges[i].ByteOffset,
1123                            vmxferpagePacket->Ranges[i].ByteCount,
1124                            netvscPacket->PageBuffers[0].Pfn,
1125                            netvscPacket->PageBuffers[0].Offset,
1126                            netvscPacket->PageBuffers[0].Length);
1127
1128                 /* Pass it to the upper layer */
1129                 ((struct netvsc_driver *)Device->Driver)->OnReceiveCallback(Device, netvscPacket);
1130
1131                 NetVscOnReceiveCompletion(netvscPacket->Completion.Recv.ReceiveCompletionContext);
1132         }
1133
1134         /* ASSERT(list_empty(&listHead)); */
1135
1136         PutNetDevice(Device);
1137 }
1138
1139 static void NetVscSendReceiveCompletion(struct hv_device *Device,
1140                                         u64 TransactionId)
1141 {
1142         struct nvsp_message recvcompMessage;
1143         int retries = 0;
1144         int ret;
1145
1146         DPRINT_DBG(NETVSC, "Sending receive completion pkt - %llx",
1147                    TransactionId);
1148
1149         recvcompMessage.Header.MessageType =
1150                                 NvspMessage1TypeSendRNDISPacketComplete;
1151
1152         /* FIXME: Pass in the status */
1153         recvcompMessage.Messages.Version1Messages.SendRNDISPacketComplete.Status = NvspStatusSuccess;
1154
1155 retry_send_cmplt:
1156         /* Send the completion */
1157         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
1158                                         &recvcompMessage,
1159                                         sizeof(struct nvsp_message),
1160                                         TransactionId,
1161                                         VmbusPacketTypeCompletion, 0);
1162         if (ret == 0) {
1163                 /* success */
1164                 /* no-op */
1165         } else if (ret == -1) {
1166                 /* no more room...wait a bit and attempt to retry 3 times */
1167                 retries++;
1168                 DPRINT_ERR(NETVSC, "unable to send receive completion pkt "
1169                            "(tid %llx)...retrying %d", TransactionId, retries);
1170
1171                 if (retries < 4) {
1172                         udelay(100);
1173                         goto retry_send_cmplt;
1174                 } else {
1175                         DPRINT_ERR(NETVSC, "unable to send receive completion "
1176                                   "pkt (tid %llx)...give up retrying",
1177                                   TransactionId);
1178                 }
1179         } else {
1180                 DPRINT_ERR(NETVSC, "unable to send receive completion pkt - "
1181                            "%llx", TransactionId);
1182         }
1183 }
1184
1185 /* Send a receive completion packet to RNDIS device (ie NetVsp) */
1186 static void NetVscOnReceiveCompletion(void *Context)
1187 {
1188         struct hv_netvsc_packet *packet = Context;
1189         struct hv_device *device = (struct hv_device *)packet->Device;
1190         struct netvsc_device *netDevice;
1191         u64 transactionId = 0;
1192         bool fSendReceiveComp = false;
1193         unsigned long flags;
1194
1195         /* ASSERT(packet->XferPagePacket); */
1196
1197         /*
1198          * Even though it seems logical to do a GetOutboundNetDevice() here to
1199          * send out receive completion, we are using GetInboundNetDevice()
1200          * since we may have disable outbound traffic already.
1201          */
1202         netDevice = GetInboundNetDevice(device);
1203         if (!netDevice) {
1204                 DPRINT_ERR(NETVSC, "unable to get net device..."
1205                            "device being destroyed?");
1206                 return;
1207         }
1208
1209         /* Overloading use of the lock. */
1210         spin_lock_irqsave(&netDevice->receive_packet_list_lock, flags);
1211
1212         /* ASSERT(packet->XferPagePacket->Count > 0); */
1213         packet->XferPagePacket->Count--;
1214
1215         /*
1216          * Last one in the line that represent 1 xfer page packet.
1217          * Return the xfer page packet itself to the freelist
1218          */
1219         if (packet->XferPagePacket->Count == 0) {
1220                 fSendReceiveComp = true;
1221                 transactionId = packet->Completion.Recv.ReceiveCompletionTid;
1222                 list_add_tail(&packet->XferPagePacket->ListEntry,
1223                               &netDevice->ReceivePacketList);
1224
1225         }
1226
1227         /* Put the packet back */
1228         list_add_tail(&packet->ListEntry, &netDevice->ReceivePacketList);
1229         spin_unlock_irqrestore(&netDevice->receive_packet_list_lock, flags);
1230
1231         /* Send a receive completion for the xfer page packet */
1232         if (fSendReceiveComp)
1233                 NetVscSendReceiveCompletion(device, transactionId);
1234
1235         PutNetDevice(device);
1236 }
1237
1238 static void NetVscOnChannelCallback(void *Context)
1239 {
1240         int ret;
1241         struct hv_device *device = Context;
1242         struct netvsc_device *netDevice;
1243         u32 bytesRecvd;
1244         u64 requestId;
1245         unsigned char *packet;
1246         struct vmpacket_descriptor *desc;
1247         unsigned char *buffer;
1248         int bufferlen = NETVSC_PACKET_SIZE;
1249
1250         /* ASSERT(device); */
1251
1252         packet = kzalloc(NETVSC_PACKET_SIZE * sizeof(unsigned char),
1253                          GFP_KERNEL);
1254         if (!packet)
1255                 return;
1256         buffer = packet;
1257
1258         netDevice = GetInboundNetDevice(device);
1259         if (!netDevice) {
1260                 DPRINT_ERR(NETVSC, "net device (%p) shutting down..."
1261                            "ignoring inbound packets", netDevice);
1262                 goto out;
1263         }
1264
1265         do {
1266                 ret = device->Driver->VmbusChannelInterface.RecvPacketRaw(
1267                                                 device, buffer, bufferlen,
1268                                                 &bytesRecvd, &requestId);
1269                 if (ret == 0) {
1270                         if (bytesRecvd > 0) {
1271                                 DPRINT_DBG(NETVSC, "receive %d bytes, tid %llx",
1272                                            bytesRecvd, requestId);
1273
1274                                 desc = (struct vmpacket_descriptor *)buffer;
1275                                 switch (desc->Type) {
1276                                 case VmbusPacketTypeCompletion:
1277                                         NetVscOnSendCompletion(device, desc);
1278                                         break;
1279
1280                                 case VmbusPacketTypeDataUsingTransferPages:
1281                                         NetVscOnReceive(device, desc);
1282                                         break;
1283
1284                                 default:
1285                                         DPRINT_ERR(NETVSC,
1286                                                    "unhandled packet type %d, "
1287                                                    "tid %llx len %d\n",
1288                                                    desc->Type, requestId,
1289                                                    bytesRecvd);
1290                                         break;
1291                                 }
1292
1293                                 /* reset */
1294                                 if (bufferlen > NETVSC_PACKET_SIZE) {
1295                                         kfree(buffer);
1296                                         buffer = packet;
1297                                         bufferlen = NETVSC_PACKET_SIZE;
1298                                 }
1299                         } else {
1300                                 /* reset */
1301                                 if (bufferlen > NETVSC_PACKET_SIZE) {
1302                                         kfree(buffer);
1303                                         buffer = packet;
1304                                         bufferlen = NETVSC_PACKET_SIZE;
1305                                 }
1306
1307                                 break;
1308                         }
1309                 } else if (ret == -2) {
1310                         /* Handle large packet */
1311                         buffer = kmalloc(bytesRecvd, GFP_ATOMIC);
1312                         if (buffer == NULL) {
1313                                 /* Try again next time around */
1314                                 DPRINT_ERR(NETVSC,
1315                                            "unable to allocate buffer of size "
1316                                            "(%d)!!", bytesRecvd);
1317                                 break;
1318                         }
1319
1320                         bufferlen = bytesRecvd;
1321                 }
1322         } while (1);
1323
1324         PutNetDevice(device);
1325 out:
1326         kfree(buffer);
1327         return;
1328 }