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