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 "RndisFilter.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         ASSERT(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_ENTER(NETVSC);
 178
 179         DPRINT_DBG(NETVSC, "sizeof(struct hv_netvsc_packet)=%zd, "
 180                    "sizeof(struct nvsp_message)=%zd, "
 181                    "sizeof(struct vmtransfer_page_packet_header)=%zd",
 182                    sizeof(struct hv_netvsc_packet),
 183                    sizeof(struct nvsp_message),
 184                    sizeof(struct vmtransfer_page_packet_header));
 185
 186         /* Make sure we are at least 2 pages since 1 page is used for control */
 187         ASSERT(driver->RingBufferSize >= (PAGE_SIZE << 1));
 188
 189         drv->name = gDriverName;
 190         memcpy(&drv->deviceType, &gNetVscDeviceType, sizeof(struct hv_guid));
 191
 192         /* Make sure it is set by the caller */
 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
 205         DPRINT_EXIT(NETVSC);
 206
 207         return 0;
 208 }
 209
 210 static int NetVscInitializeReceiveBufferWithNetVsp(struct hv_device *Device)
 211 {
 212         int ret = 0;
 213         struct netvsc_device *netDevice;
 214         struct nvsp_message *initPacket;
 215
 216         DPRINT_ENTER(NETVSC);
 217
 218         netDevice = GetOutboundNetDevice(Device);
 219         if (!netDevice) {
 220                 DPRINT_ERR(NETVSC, "unable to get net device..."
 221                            "device being destroyed?");
 222                 DPRINT_EXIT(NETVSC);
 223                 return -1;
 224         }
 225         ASSERT(netDevice->ReceiveBufferSize > 0);
 226         /* page-size grandularity */
 227         ASSERT((netDevice->ReceiveBufferSize & (PAGE_SIZE - 1)) == 0);
 228
 229         netDevice->ReceiveBuffer =
 230                 osd_PageAlloc(netDevice->ReceiveBufferSize >> PAGE_SHIFT);
 231         if (!netDevice->ReceiveBuffer) {
 232                 DPRINT_ERR(NETVSC,
 233                            "unable to allocate receive buffer of size %d",
 234                            netDevice->ReceiveBufferSize);
 235                 ret = -1;
 236                 goto Cleanup;
 237         }
 238         /* page-aligned buffer */
 239         ASSERT(((unsigned long)netDevice->ReceiveBuffer & (PAGE_SIZE - 1)) ==
 240                 0);
 241
 242         DPRINT_INFO(NETVSC, "Establishing receive buffer's GPADL...");
 243
 244         /*
 245          * Establish the gpadl handle for this buffer on this
 246          * channel.  Note: This call uses the vmbus connection rather
 247          * than the channel to establish the gpadl handle.
 248          */
 249         ret = Device->Driver->VmbusChannelInterface.EstablishGpadl(Device,
 250                                         netDevice->ReceiveBuffer,
 251                                         netDevice->ReceiveBufferSize,
 252                                         &netDevice->ReceiveBufferGpadlHandle);
 253         if (ret != 0) {
 254                 DPRINT_ERR(NETVSC,
 255                            "unable to establish receive buffer's gpadl");
 256                 goto Cleanup;
 257         }
 258
 259         /* osd_WaitEventWait(ext->ChannelInitEvent); */
 260
 261         /* Notify the NetVsp of the gpadl handle */
 262         DPRINT_INFO(NETVSC, "Sending NvspMessage1TypeSendReceiveBuffer...");
 263
 264         initPacket = &netDevice->ChannelInitPacket;
 265
 266         memset(initPacket, 0, sizeof(struct nvsp_message));
 267
 268         initPacket->Header.MessageType = NvspMessage1TypeSendReceiveBuffer;
 269         initPacket->Messages.Version1Messages.SendReceiveBuffer.GpadlHandle = netDevice->ReceiveBufferGpadlHandle;
 270         initPacket->Messages.Version1Messages.SendReceiveBuffer.Id = NETVSC_RECEIVE_BUFFER_ID;
 271
 272         /* Send the gpadl notification request */
 273         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 274                                 initPacket,
 275                                 sizeof(struct nvsp_message),
 276                                 (unsigned long)initPacket,
 277                                 VmbusPacketTypeDataInBand,
 278                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 279         if (ret != 0) {
 280                 DPRINT_ERR(NETVSC,
 281                            "unable to send receive buffer's gpadl to netvsp");
 282                 goto Cleanup;
 283         }
 284
 285         osd_WaitEventWait(netDevice->ChannelInitEvent);
 286
 287         /* Check the response */
 288         if (initPacket->Messages.Version1Messages.SendReceiveBufferComplete.Status != NvspStatusSuccess) {
 289                 DPRINT_ERR(NETVSC, "Unable to complete receive buffer "
 290                            "initialzation with NetVsp - status %d",
 291                            initPacket->Messages.Version1Messages.SendReceiveBufferComplete.Status);
 292                 ret = -1;
 293                 goto Cleanup;
 294         }
 295
 296         /* Parse the response */
 297         ASSERT(netDevice->ReceiveSectionCount == 0);
 298         ASSERT(netDevice->ReceiveSections == NULL);
 299
 300         netDevice->ReceiveSectionCount = initPacket->Messages.Version1Messages.SendReceiveBufferComplete.NumSections;
 301
 302         netDevice->ReceiveSections = kmalloc(netDevice->ReceiveSectionCount * sizeof(struct nvsp_1_receive_buffer_section), GFP_KERNEL);
 303         if (netDevice->ReceiveSections == NULL) {
 304                 ret = -1;
 305                 goto Cleanup;
 306         }
 307
 308         memcpy(netDevice->ReceiveSections,
 309                 initPacket->Messages.Version1Messages.SendReceiveBufferComplete.Sections,
 310                 netDevice->ReceiveSectionCount * sizeof(struct nvsp_1_receive_buffer_section));
 311
 312         DPRINT_INFO(NETVSC, "Receive sections info (count %d, offset %d, "
 313                     "endoffset %d, suballoc size %d, num suballocs %d)",
 314                     netDevice->ReceiveSectionCount,
 315                     netDevice->ReceiveSections[0].Offset,
 316                     netDevice->ReceiveSections[0].EndOffset,
 317                     netDevice->ReceiveSections[0].SubAllocationSize,
 318                     netDevice->ReceiveSections[0].NumSubAllocations);
 319
 320         /*
 321          * For 1st release, there should only be 1 section that represents the
 322          * entire receive buffer
 323          */
 324         if (netDevice->ReceiveSectionCount != 1 ||
 325             netDevice->ReceiveSections->Offset != 0) {
 326                 ret = -1;
 327                 goto Cleanup;
 328         }
 329
 330         goto Exit;
 331
 332 Cleanup:
 333         NetVscDestroyReceiveBuffer(netDevice);
 334
 335 Exit:
 336         PutNetDevice(Device);
 337         DPRINT_EXIT(NETVSC);
 338         return ret;
 339 }
 340
 341 static int NetVscInitializeSendBufferWithNetVsp(struct hv_device *Device)
 342 {
 343         int ret = 0;
 344         struct netvsc_device *netDevice;
 345         struct nvsp_message *initPacket;
 346
 347         DPRINT_ENTER(NETVSC);
 348
 349         netDevice = GetOutboundNetDevice(Device);
 350         if (!netDevice) {
 351                 DPRINT_ERR(NETVSC, "unable to get net device..."
 352                            "device being destroyed?");
 353                 DPRINT_EXIT(NETVSC);
 354                 return -1;
 355         }
 356         ASSERT(netDevice->SendBufferSize > 0);
 357         /* page-size grandularity */
 358         ASSERT((netDevice->SendBufferSize & (PAGE_SIZE - 1)) == 0);
 359
 360         netDevice->SendBuffer =
 361                 osd_PageAlloc(netDevice->SendBufferSize >> PAGE_SHIFT);
 362         if (!netDevice->SendBuffer) {
 363                 DPRINT_ERR(NETVSC, "unable to allocate send buffer of size %d",
 364                            netDevice->SendBufferSize);
 365                 ret = -1;
 366                 goto Cleanup;
 367         }
 368         /* page-aligned buffer */
 369         ASSERT(((unsigned long)netDevice->SendBuffer & (PAGE_SIZE - 1)) == 0);
 370
 371         DPRINT_INFO(NETVSC, "Establishing send buffer's GPADL...");
 372
 373         /*
 374          * Establish the gpadl handle for this buffer on this
 375          * channel.  Note: This call uses the vmbus connection rather
 376          * than the channel to establish the gpadl handle.
 377          */
 378         ret = Device->Driver->VmbusChannelInterface.EstablishGpadl(Device,
 379                                         netDevice->SendBuffer,
 380                                         netDevice->SendBufferSize,
 381                                         &netDevice->SendBufferGpadlHandle);
 382         if (ret != 0) {
 383                 DPRINT_ERR(NETVSC, "unable to establish send buffer's gpadl");
 384                 goto Cleanup;
 385         }
 386
 387         /* osd_WaitEventWait(ext->ChannelInitEvent); */
 388
 389         /* Notify the NetVsp of the gpadl handle */
 390         DPRINT_INFO(NETVSC, "Sending NvspMessage1TypeSendSendBuffer...");
 391
 392         initPacket = &netDevice->ChannelInitPacket;
 393
 394         memset(initPacket, 0, sizeof(struct nvsp_message));
 395
 396         initPacket->Header.MessageType = NvspMessage1TypeSendSendBuffer;
 397         initPacket->Messages.Version1Messages.SendReceiveBuffer.GpadlHandle = netDevice->SendBufferGpadlHandle;
 398         initPacket->Messages.Version1Messages.SendReceiveBuffer.Id = NETVSC_SEND_BUFFER_ID;
 399
 400         /* Send the gpadl notification request */
 401         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 402                                 initPacket, sizeof(struct nvsp_message),
 403                                 (unsigned long)initPacket,
 404                                 VmbusPacketTypeDataInBand,
 405                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 406         if (ret != 0) {
 407                 DPRINT_ERR(NETVSC,
 408                            "unable to send receive buffer's gpadl to netvsp");
 409                 goto Cleanup;
 410         }
 411
 412         osd_WaitEventWait(netDevice->ChannelInitEvent);
 413
 414         /* Check the response */
 415         if (initPacket->Messages.Version1Messages.SendSendBufferComplete.Status != NvspStatusSuccess) {
 416                 DPRINT_ERR(NETVSC, "Unable to complete send buffer "
 417                            "initialzation with NetVsp - status %d",
 418                            initPacket->Messages.Version1Messages.SendSendBufferComplete.Status);
 419                 ret = -1;
 420                 goto Cleanup;
 421         }
 422
 423         netDevice->SendSectionSize = initPacket->Messages.Version1Messages.SendSendBufferComplete.SectionSize;
 424
 425         goto Exit;
 426
 427 Cleanup:
 428         NetVscDestroySendBuffer(netDevice);
 429
 430 Exit:
 431         PutNetDevice(Device);
 432         DPRINT_EXIT(NETVSC);
 433         return ret;
 434 }
 435
 436 static int NetVscDestroyReceiveBuffer(struct netvsc_device *NetDevice)
 437 {
 438         struct nvsp_message *revokePacket;
 439         int ret = 0;
 440
 441         DPRINT_ENTER(NETVSC);
 442
 443         /*
 444          * If we got a section count, it means we received a
 445          * SendReceiveBufferComplete msg (ie sent
 446          * NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
 447          * to send a revoke msg here
 448          */
 449         if (NetDevice->ReceiveSectionCount) {
 450                 DPRINT_INFO(NETVSC,
 451                             "Sending NvspMessage1TypeRevokeReceiveBuffer...");
 452
 453                 /* Send the revoke receive buffer */
 454                 revokePacket = &NetDevice->RevokePacket;
 455                 memset(revokePacket, 0, sizeof(struct nvsp_message));
 456
 457                 revokePacket->Header.MessageType = NvspMessage1TypeRevokeReceiveBuffer;
 458                 revokePacket->Messages.Version1Messages.RevokeReceiveBuffer.Id = NETVSC_RECEIVE_BUFFER_ID;
 459
 460                 ret = NetDevice->Device->Driver->VmbusChannelInterface.SendPacket(
 461                                                 NetDevice->Device,
 462                                                 revokePacket,
 463                                                 sizeof(struct nvsp_message),
 464                                                 (unsigned long)revokePacket,
 465                                                 VmbusPacketTypeDataInBand, 0);
 466                 /*
 467                  * If we failed here, we might as well return and
 468                  * have a leak rather than continue and a bugchk
 469                  */
 470                 if (ret != 0) {
 471                         DPRINT_ERR(NETVSC, "unable to send revoke receive "
 472                                    "buffer to netvsp");
 473                         DPRINT_EXIT(NETVSC);
 474                         return -1;
 475                 }
 476         }
 477
 478         /* Teardown the gpadl on the vsp end */
 479         if (NetDevice->ReceiveBufferGpadlHandle) {
 480                 DPRINT_INFO(NETVSC, "Tearing down receive buffer's GPADL...");
 481
 482                 ret = NetDevice->Device->Driver->VmbusChannelInterface.TeardownGpadl(
 483                                         NetDevice->Device,
 484                                         NetDevice->ReceiveBufferGpadlHandle);
 485
 486                 /* If we failed here, we might as well return and have a leak rather than continue and a bugchk */
 487                 if (ret != 0) {
 488                         DPRINT_ERR(NETVSC,
 489                                    "unable to teardown receive buffer's gpadl");
 490                         DPRINT_EXIT(NETVSC);
 491                         return -1;
 492                 }
 493                 NetDevice->ReceiveBufferGpadlHandle = 0;
 494         }
 495
 496         if (NetDevice->ReceiveBuffer) {
 497                 DPRINT_INFO(NETVSC, "Freeing up receive buffer...");
 498
 499                 /* Free up the receive buffer */
 500                 osd_PageFree(NetDevice->ReceiveBuffer,
 501                              NetDevice->ReceiveBufferSize >> PAGE_SHIFT);
 502                 NetDevice->ReceiveBuffer = NULL;
 503         }
 504
 505         if (NetDevice->ReceiveSections) {
 506                 NetDevice->ReceiveSectionCount = 0;
 507                 kfree(NetDevice->ReceiveSections);
 508                 NetDevice->ReceiveSections = NULL;
 509         }
 510
 511         DPRINT_EXIT(NETVSC);
 512
 513         return ret;
 514 }
 515
 516 static int NetVscDestroySendBuffer(struct netvsc_device *NetDevice)
 517 {
 518         struct nvsp_message *revokePacket;
 519         int ret = 0;
 520
 521         DPRINT_ENTER(NETVSC);
 522
 523         /*
 524          * If we got a section count, it means we received a
 525          *  SendReceiveBufferComplete msg (ie sent
 526          *  NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
 527          *  to send a revoke msg here
 528          */
 529         if (NetDevice->SendSectionSize) {
 530                 DPRINT_INFO(NETVSC,
 531                             "Sending NvspMessage1TypeRevokeSendBuffer...");
 532
 533                 /* Send the revoke send buffer */
 534                 revokePacket = &NetDevice->RevokePacket;
 535                 memset(revokePacket, 0, sizeof(struct nvsp_message));
 536
 537                 revokePacket->Header.MessageType = NvspMessage1TypeRevokeSendBuffer;
 538                 revokePacket->Messages.Version1Messages.RevokeSendBuffer.Id = NETVSC_SEND_BUFFER_ID;
 539
 540                 ret = NetDevice->Device->Driver->VmbusChannelInterface.SendPacket(NetDevice->Device,
 541                                         revokePacket,
 542                                         sizeof(struct nvsp_message),
 543                                         (unsigned long)revokePacket,
 544                                         VmbusPacketTypeDataInBand, 0);
 545                 /*
 546                  * If we failed here, we might as well return and have a leak
 547                  * rather than continue and a bugchk
 548                  */
 549                 if (ret != 0) {
 550                         DPRINT_ERR(NETVSC, "unable to send revoke send buffer "
 551                                    "to netvsp");
 552                         DPRINT_EXIT(NETVSC);
 553                         return -1;
 554                 }
 555         }
 556
 557         /* Teardown the gpadl on the vsp end */
 558         if (NetDevice->SendBufferGpadlHandle) {
 559                 DPRINT_INFO(NETVSC, "Tearing down send buffer's GPADL...");
 560
 561                 ret = NetDevice->Device->Driver->VmbusChannelInterface.TeardownGpadl(NetDevice->Device, NetDevice->SendBufferGpadlHandle);
 562
 563                 /*
 564                  * If we failed here, we might as well return and have a leak
 565                  * rather than continue and a bugchk
 566                  */
 567                 if (ret != 0) {
 568                         DPRINT_ERR(NETVSC, "unable to teardown send buffer's "
 569                                    "gpadl");
 570                         DPRINT_EXIT(NETVSC);
 571                         return -1;
 572                 }
 573                 NetDevice->SendBufferGpadlHandle = 0;
 574         }
 575
 576         if (NetDevice->SendBuffer) {
 577                 DPRINT_INFO(NETVSC, "Freeing up send buffer...");
 578
 579                 /* Free up the receive buffer */
 580                 osd_PageFree(NetDevice->SendBuffer,
 581                              NetDevice->SendBufferSize >> PAGE_SHIFT);
 582                 NetDevice->SendBuffer = NULL;
 583         }
 584
 585         DPRINT_EXIT(NETVSC);
 586
 587         return ret;
 588 }
 589
 590
 591 static int NetVscConnectToVsp(struct hv_device *Device)
 592 {
 593         int ret;
 594         struct netvsc_device *netDevice;
 595         struct nvsp_message *initPacket;
 596         int ndisVersion;
 597
 598         DPRINT_ENTER(NETVSC);
 599
 600         netDevice = GetOutboundNetDevice(Device);
 601         if (!netDevice) {
 602                 DPRINT_ERR(NETVSC, "unable to get net device..."
 603                            "device being destroyed?");
 604                 DPRINT_EXIT(NETVSC);
 605                 return -1;
 606         }
 607
 608         initPacket = &netDevice->ChannelInitPacket;
 609
 610         memset(initPacket, 0, sizeof(struct nvsp_message));
 611         initPacket->Header.MessageType = NvspMessageTypeInit;
 612         initPacket->Messages.InitMessages.Init.MinProtocolVersion = NVSP_MIN_PROTOCOL_VERSION;
 613         initPacket->Messages.InitMessages.Init.MaxProtocolVersion = NVSP_MAX_PROTOCOL_VERSION;
 614
 615         DPRINT_INFO(NETVSC, "Sending NvspMessageTypeInit...");
 616
 617         /* Send the init request */
 618         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 619                                 initPacket,
 620                                 sizeof(struct nvsp_message),
 621                                 (unsigned long)initPacket,
 622                                 VmbusPacketTypeDataInBand,
 623                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 624
 625         if (ret != 0) {
 626                 DPRINT_ERR(NETVSC, "unable to send NvspMessageTypeInit");
 627                 goto Cleanup;
 628         }
 629
 630         osd_WaitEventWait(netDevice->ChannelInitEvent);
 631
 632         /* Now, check the response */
 633         /* ASSERT(initPacket->Messages.InitMessages.InitComplete.MaximumMdlChainLength <= MAX_MULTIPAGE_BUFFER_COUNT); */
 634         DPRINT_INFO(NETVSC, "NvspMessageTypeInit status(%d) max mdl chain (%d)",
 635                 initPacket->Messages.InitMessages.InitComplete.Status,
 636                 initPacket->Messages.InitMessages.InitComplete.MaximumMdlChainLength);
 637
 638         if (initPacket->Messages.InitMessages.InitComplete.Status !=
 639             NvspStatusSuccess) {
 640                 DPRINT_ERR(NETVSC,
 641                         "unable to initialize with netvsp (status 0x%x)",
 642                         initPacket->Messages.InitMessages.InitComplete.Status);
 643                 ret = -1;
 644                 goto Cleanup;
 645         }
 646
 647         if (initPacket->Messages.InitMessages.InitComplete.NegotiatedProtocolVersion != NVSP_PROTOCOL_VERSION_1) {
 648                 DPRINT_ERR(NETVSC, "unable to initialize with netvsp "
 649                            "(version expected 1 got %d)",
 650                            initPacket->Messages.InitMessages.InitComplete.NegotiatedProtocolVersion);
 651                 ret = -1;
 652                 goto Cleanup;
 653         }
 654         DPRINT_INFO(NETVSC, "Sending NvspMessage1TypeSendNdisVersion...");
 655
 656         /* Send the ndis version */
 657         memset(initPacket, 0, sizeof(struct nvsp_message));
 658
 659         ndisVersion = 0x00050000;
 660
 661         initPacket->Header.MessageType = NvspMessage1TypeSendNdisVersion;
 662         initPacket->Messages.Version1Messages.SendNdisVersion.NdisMajorVersion =
 663                                 (ndisVersion & 0xFFFF0000) >> 16;
 664         initPacket->Messages.Version1Messages.SendNdisVersion.NdisMinorVersion =
 665                                 ndisVersion & 0xFFFF;
 666
 667         /* Send the init request */
 668         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 669                                         initPacket,
 670                                         sizeof(struct nvsp_message),
 671                                         (unsigned long)initPacket,
 672                                         VmbusPacketTypeDataInBand, 0);
 673         if (ret != 0) {
 674                 DPRINT_ERR(NETVSC,
 675                            "unable to send NvspMessage1TypeSendNdisVersion");
 676                 ret = -1;
 677                 goto Cleanup;
 678         }
 679         /*
 680          * BUGBUG - We have to wait for the above msg since the
 681          * netvsp uses KMCL which acknowledges packet (completion
 682          * packet) since our Vmbus always set the
 683          * VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED flag
 684          */
 685          /* osd_WaitEventWait(NetVscChannel->ChannelInitEvent); */
 686
 687         /* Post the big receive buffer to NetVSP */
 688         ret = NetVscInitializeReceiveBufferWithNetVsp(Device);
 689         if (ret == 0)
 690                 ret = NetVscInitializeSendBufferWithNetVsp(Device);
 691
 692 Cleanup:
 693         PutNetDevice(Device);
 694         DPRINT_EXIT(NETVSC);
 695         return ret;
 696 }
 697
 698 static void NetVscDisconnectFromVsp(struct netvsc_device *NetDevice)
 699 {
 700         DPRINT_ENTER(NETVSC);
 701
 702         NetVscDestroyReceiveBuffer(NetDevice);
 703         NetVscDestroySendBuffer(NetDevice);
 704
 705         DPRINT_EXIT(NETVSC);
 706 }
 707
 708 /**
 709  * NetVscOnDeviceAdd - Callback when the device belonging to this driver is added
 710  */
 711 static int NetVscOnDeviceAdd(struct hv_device *Device, void *AdditionalInfo)
 712 {
 713         int ret = 0;
 714         int i;
 715         struct netvsc_device *netDevice;
 716         struct hv_netvsc_packet *packet, *pos;
 717         struct netvsc_driver *netDriver =
 718                                 (struct netvsc_driver *)Device->Driver;
 719
 720         DPRINT_ENTER(NETVSC);
 721
 722         netDevice = AllocNetDevice(Device);
 723         if (!netDevice) {
 724                 ret = -1;
 725                 goto Cleanup;
 726         }
 727
 728         DPRINT_DBG(NETVSC, "netvsc channel object allocated - %p", netDevice);
 729
 730         /* Initialize the NetVSC channel extension */
 731         netDevice->ReceiveBufferSize = NETVSC_RECEIVE_BUFFER_SIZE;
 732         spin_lock_init(&netDevice->receive_packet_list_lock);
 733
 734         netDevice->SendBufferSize = NETVSC_SEND_BUFFER_SIZE;
 735
 736         INIT_LIST_HEAD(&netDevice->ReceivePacketList);
 737
 738         for (i = 0; i < NETVSC_RECEIVE_PACKETLIST_COUNT; i++) {
 739                 packet = kzalloc(sizeof(struct hv_netvsc_packet) +
 740                                  (NETVSC_RECEIVE_SG_COUNT *
 741                                   sizeof(struct hv_page_buffer)), GFP_KERNEL);
 742                 if (!packet) {
 743                         DPRINT_DBG(NETVSC, "unable to allocate netvsc pkts "
 744                                    "for receive pool (wanted %d got %d)",
 745                                    NETVSC_RECEIVE_PACKETLIST_COUNT, i);
 746                         break;
 747                 }
 748                 list_add_tail(&packet->ListEntry,
 749                               &netDevice->ReceivePacketList);
 750         }
 751         netDevice->ChannelInitEvent = osd_WaitEventCreate();
 752
 753         /* Open the channel */
 754         ret = Device->Driver->VmbusChannelInterface.Open(Device,
 755                                                 netDriver->RingBufferSize,
 756                                                 netDriver->RingBufferSize,
 757                                                 NULL, 0,
 758                                                 NetVscOnChannelCallback,
 759                                                 Device);
 760
 761         if (ret != 0) {
 762                 DPRINT_ERR(NETVSC, "unable to open channel: %d", ret);
 763                 ret = -1;
 764                 goto Cleanup;
 765         }
 766
 767         /* Channel is opened */
 768         DPRINT_INFO(NETVSC, "*** NetVSC channel opened successfully! ***");
 769
 770         /* Connect with the NetVsp */
 771         ret = NetVscConnectToVsp(Device);
 772         if (ret != 0) {
 773                 DPRINT_ERR(NETVSC, "unable to connect to NetVSP - %d", ret);
 774                 ret = -1;
 775                 goto Close;
 776         }
 777
 778         DPRINT_INFO(NETVSC, "*** NetVSC channel handshake result - %d ***",
 779                     ret);
 780
 781         DPRINT_EXIT(NETVSC);
 782         return ret;
 783
 784 Close:
 785         /* Now, we can close the channel safely */
 786         Device->Driver->VmbusChannelInterface.Close(Device);
 787
 788 Cleanup:
 789
 790         if (netDevice) {
 791                 kfree(netDevice->ChannelInitEvent);
 792
 793                 list_for_each_entry_safe(packet, pos,
 794                                          &netDevice->ReceivePacketList,
 795                                          ListEntry) {
 796                         list_del(&packet->ListEntry);
 797                         kfree(packet);
 798                 }
 799
 800                 ReleaseOutboundNetDevice(Device);
 801                 ReleaseInboundNetDevice(Device);
 802
 803                 FreeNetDevice(netDevice);
 804         }
 805
 806         DPRINT_EXIT(NETVSC);
 807         return ret;
 808 }
 809
 810 /**
 811  * NetVscOnDeviceRemove - Callback when the root bus device is removed
 812  */
 813 static int NetVscOnDeviceRemove(struct hv_device *Device)
 814 {
 815         struct netvsc_device *netDevice;
 816         struct hv_netvsc_packet *netvscPacket, *pos;
 817
 818         DPRINT_ENTER(NETVSC);
 819
 820         DPRINT_INFO(NETVSC, "Disabling outbound traffic on net device (%p)...",
 821                     Device->Extension);
 822
 823         /* Stop outbound traffic ie sends and receives completions */
 824         netDevice = ReleaseOutboundNetDevice(Device);
 825         if (!netDevice) {
 826                 DPRINT_ERR(NETVSC, "No net device present!!");
 827                 return -1;
 828         }
 829
 830         /* Wait for all send completions */
 831         while (atomic_read(&netDevice->NumOutstandingSends)) {
 832                 DPRINT_INFO(NETVSC, "waiting for %d requests to complete...",
 833                             atomic_read(&netDevice->NumOutstandingSends));
 834                 udelay(100);
 835         }
 836
 837         DPRINT_INFO(NETVSC, "Disconnecting from netvsp...");
 838
 839         NetVscDisconnectFromVsp(netDevice);
 840
 841         DPRINT_INFO(NETVSC, "Disabling inbound traffic on net device (%p)...",
 842                     Device->Extension);
 843
 844         /* Stop inbound traffic ie receives and sends completions */
 845         netDevice = ReleaseInboundNetDevice(Device);
 846
 847         /* At this point, no one should be accessing netDevice except in here */
 848         DPRINT_INFO(NETVSC, "net device (%p) safe to remove", netDevice);
 849
 850         /* Now, we can close the channel safely */
 851         Device->Driver->VmbusChannelInterface.Close(Device);
 852
 853         /* Release all resources */
 854         list_for_each_entry_safe(netvscPacket, pos,
 855                                  &netDevice->ReceivePacketList, ListEntry) {
 856                 list_del(&netvscPacket->ListEntry);
 857                 kfree(netvscPacket);
 858         }
 859
 860         kfree(netDevice->ChannelInitEvent);
 861         FreeNetDevice(netDevice);
 862
 863         DPRINT_EXIT(NETVSC);
 864         return 0;
 865 }
 866
 867 /**
 868  * NetVscOnCleanup - Perform any cleanup when the driver is removed
 869  */
 870 static void NetVscOnCleanup(struct hv_driver *drv)
 871 {
 872         DPRINT_ENTER(NETVSC);
 873         DPRINT_EXIT(NETVSC);
 874 }
 875
 876 static void NetVscOnSendCompletion(struct hv_device *Device,
 877                                    struct vmpacket_descriptor *Packet)
 878 {
 879         struct netvsc_device *netDevice;
 880         struct nvsp_message *nvspPacket;
 881         struct hv_netvsc_packet *nvscPacket;
 882
 883         DPRINT_ENTER(NETVSC);
 884
 885         netDevice = GetInboundNetDevice(Device);
 886         if (!netDevice) {
 887                 DPRINT_ERR(NETVSC, "unable to get net device..."
 888                            "device being destroyed?");
 889                 DPRINT_EXIT(NETVSC);
 890                 return;
 891         }
 892
 893         nvspPacket = (struct nvsp_message *)((unsigned long)Packet + (Packet->DataOffset8 << 3));
 894
 895         DPRINT_DBG(NETVSC, "send completion packet - type %d",
 896                    nvspPacket->Header.MessageType);
 897
 898         if ((nvspPacket->Header.MessageType == NvspMessageTypeInitComplete) ||
 899             (nvspPacket->Header.MessageType ==
 900              NvspMessage1TypeSendReceiveBufferComplete) ||
 901             (nvspPacket->Header.MessageType ==
 902              NvspMessage1TypeSendSendBufferComplete)) {
 903                 /* Copy the response back */
 904                 memcpy(&netDevice->ChannelInitPacket, nvspPacket,
 905                        sizeof(struct nvsp_message));
 906                 osd_WaitEventSet(netDevice->ChannelInitEvent);
 907         } else if (nvspPacket->Header.MessageType ==
 908                    NvspMessage1TypeSendRNDISPacketComplete) {
 909                 /* Get the send context */
 910                 nvscPacket = (struct hv_netvsc_packet *)(unsigned long)Packet->TransactionId;
 911                 ASSERT(nvscPacket);
 912
 913                 /* Notify the layer above us */
 914                 nvscPacket->Completion.Send.OnSendCompletion(nvscPacket->Completion.Send.SendCompletionContext);
 915
 916                 atomic_dec(&netDevice->NumOutstandingSends);
 917         } else {
 918                 DPRINT_ERR(NETVSC, "Unknown send completion packet type - "
 919                            "%d received!!", nvspPacket->Header.MessageType);
 920         }
 921
 922         PutNetDevice(Device);
 923         DPRINT_EXIT(NETVSC);
 924 }
 925
 926 static int NetVscOnSend(struct hv_device *Device,
 927                         struct hv_netvsc_packet *Packet)
 928 {
 929         struct netvsc_device *netDevice;
 930         int ret = 0;
 931
 932         struct nvsp_message sendMessage;
 933
 934         DPRINT_ENTER(NETVSC);
 935
 936         netDevice = GetOutboundNetDevice(Device);
 937         if (!netDevice) {
 938                 DPRINT_ERR(NETVSC, "net device (%p) shutting down..."
 939                            "ignoring outbound packets", netDevice);
 940                 DPRINT_EXIT(NETVSC);
 941                 return -2;
 942         }
 943
 944         sendMessage.Header.MessageType = NvspMessage1TypeSendRNDISPacket;
 945         if (Packet->IsDataPacket) {
 946                 /* 0 is RMC_DATA; */
 947                 sendMessage.Messages.Version1Messages.SendRNDISPacket.ChannelType = 0;
 948         } else {
 949                 /* 1 is RMC_CONTROL; */
 950                 sendMessage.Messages.Version1Messages.SendRNDISPacket.ChannelType = 1;
 951         }
 952
 953         /* Not using send buffer section */
 954         sendMessage.Messages.Version1Messages.SendRNDISPacket.SendBufferSectionIndex = 0xFFFFFFFF;
 955         sendMessage.Messages.Version1Messages.SendRNDISPacket.SendBufferSectionSize = 0;
 956
 957         if (Packet->PageBufferCount) {
 958                 ret = Device->Driver->VmbusChannelInterface.SendPacketPageBuffer(
 959                                         Device, Packet->PageBuffers,
 960                                         Packet->PageBufferCount,
 961                                         &sendMessage,
 962                                         sizeof(struct nvsp_message),
 963                                         (unsigned long)Packet);
 964         } else {
 965                 ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 966                                 &sendMessage,
 967                                 sizeof(struct nvsp_message),
 968                                 (unsigned long)Packet,
 969                                 VmbusPacketTypeDataInBand,
 970                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 971
 972         }
 973
 974         if (ret != 0)
 975                 DPRINT_ERR(NETVSC, "Unable to send packet %p ret %d",
 976                            Packet, ret);
 977
 978         atomic_inc(&netDevice->NumOutstandingSends);
 979         PutNetDevice(Device);
 980
 981         DPRINT_EXIT(NETVSC);
 982         return ret;
 983 }
 984
 985 static void NetVscOnReceive(struct hv_device *Device,
 986                             struct vmpacket_descriptor *Packet)
 987 {
 988         struct netvsc_device *netDevice;
 989         struct vmtransfer_page_packet_header *vmxferpagePacket;
 990         struct nvsp_message *nvspPacket;
 991         struct hv_netvsc_packet *netvscPacket = NULL;
 992         unsigned long start;
 993         unsigned long end, endVirtual;
 994         /* struct netvsc_driver *netvscDriver; */
 995         struct xferpage_packet *xferpagePacket = NULL;
 996         int i, j;
 997         int count = 0, bytesRemain = 0;
 998         unsigned long flags;
 999         LIST_HEAD(listHead);
1000
1001         DPRINT_ENTER(NETVSC);
1002
1003         netDevice = GetInboundNetDevice(Device);
1004         if (!netDevice) {
1005                 DPRINT_ERR(NETVSC, "unable to get net device..."
1006                            "device being destroyed?");
1007                 DPRINT_EXIT(NETVSC);
1008                 return;
1009         }
1010
1011         /*
1012          * All inbound packets other than send completion should be xfer page
1013          * packet
1014          */
1015         if (Packet->Type != VmbusPacketTypeDataUsingTransferPages) {
1016                 DPRINT_ERR(NETVSC, "Unknown packet type received - %d",
1017                            Packet->Type);
1018                 PutNetDevice(Device);
1019                 return;
1020         }
1021
1022         nvspPacket = (struct nvsp_message *)((unsigned long)Packet +
1023                         (Packet->DataOffset8 << 3));
1024
1025         /* Make sure this is a valid nvsp packet */
1026         if (nvspPacket->Header.MessageType != NvspMessage1TypeSendRNDISPacket) {
1027                 DPRINT_ERR(NETVSC, "Unknown nvsp packet type received - %d",
1028                            nvspPacket->Header.MessageType);
1029                 PutNetDevice(Device);
1030                 return;
1031         }
1032
1033         DPRINT_DBG(NETVSC, "NVSP packet received - type %d",
1034                    nvspPacket->Header.MessageType);
1035
1036         vmxferpagePacket = (struct vmtransfer_page_packet_header *)Packet;
1037
1038         if (vmxferpagePacket->TransferPageSetId != NETVSC_RECEIVE_BUFFER_ID) {
1039                 DPRINT_ERR(NETVSC, "Invalid xfer page set id - "
1040                            "expecting %x got %x", NETVSC_RECEIVE_BUFFER_ID,
1041                            vmxferpagePacket->TransferPageSetId);
1042                 PutNetDevice(Device);
1043                 return;
1044         }
1045
1046         DPRINT_DBG(NETVSC, "xfer page - range count %d",
1047                    vmxferpagePacket->RangeCount);
1048
1049         /*
1050          * Grab free packets (range count + 1) to represent this xfer
1051          * page packet. +1 to represent the xfer page packet itself.
1052          * We grab it here so that we know exactly how many we can
1053          * fulfil
1054          */
1055         spin_lock_irqsave(&netDevice->receive_packet_list_lock, flags);
1056         while (!list_empty(&netDevice->ReceivePacketList)) {
1057                 list_move_tail(netDevice->ReceivePacketList.next, &listHead);
1058                 if (++count == vmxferpagePacket->RangeCount + 1)
1059                         break;
1060         }
1061         spin_unlock_irqrestore(&netDevice->receive_packet_list_lock, flags);
1062
1063         /*
1064          * We need at least 2 netvsc pkts (1 to represent the xfer
1065          * page and at least 1 for the range) i.e. we can handled
1066          * some of the xfer page packet ranges...
1067          */
1068         if (count < 2) {
1069                 DPRINT_ERR(NETVSC, "Got only %d netvsc pkt...needed %d pkts. "
1070                            "Dropping this xfer page packet completely!",
1071                            count, vmxferpagePacket->RangeCount + 1);
1072
1073                 /* Return it to the freelist */
1074                 spin_lock_irqsave(&netDevice->receive_packet_list_lock, flags);
1075                 for (i = count; i != 0; i--) {
1076                         list_move_tail(listHead.next,
1077                                        &netDevice->ReceivePacketList);
1078                 }
1079                 spin_unlock_irqrestore(&netDevice->receive_packet_list_lock,
1080                                        flags);
1081
1082                 NetVscSendReceiveCompletion(Device,
1083                                             vmxferpagePacket->d.TransactionId);
1084
1085                 PutNetDevice(Device);
1086                 return;
1087         }
1088
1089         /* Remove the 1st packet to represent the xfer page packet itself */
1090         xferpagePacket = (struct xferpage_packet*)listHead.next;
1091         list_del(&xferpagePacket->ListEntry);
1092
1093         /* This is how much we can satisfy */
1094         xferpagePacket->Count = count - 1;
1095         ASSERT(xferpagePacket->Count > 0 && xferpagePacket->Count <=
1096                 vmxferpagePacket->RangeCount);
1097
1098         if (xferpagePacket->Count != vmxferpagePacket->RangeCount) {
1099                 DPRINT_INFO(NETVSC, "Needed %d netvsc pkts to satisy this xfer "
1100                             "page...got %d", vmxferpagePacket->RangeCount,
1101                             xferpagePacket->Count);
1102         }
1103
1104         /* Each range represents 1 RNDIS pkt that contains 1 ethernet frame */
1105         for (i = 0; i < (count - 1); i++) {
1106                 netvscPacket = (struct hv_netvsc_packet*)listHead.next;
1107                 list_del(&netvscPacket->ListEntry);
1108
1109                 /* Initialize the netvsc packet */
1110                 netvscPacket->XferPagePacket = xferpagePacket;
1111                 netvscPacket->Completion.Recv.OnReceiveCompletion =
1112                                         NetVscOnReceiveCompletion;
1113                 netvscPacket->Completion.Recv.ReceiveCompletionContext =
1114                                         netvscPacket;
1115                 netvscPacket->Device = Device;
1116                 /* Save this so that we can send it back */
1117                 netvscPacket->Completion.Recv.ReceiveCompletionTid =
1118                                         vmxferpagePacket->d.TransactionId;
1119
1120                 netvscPacket->TotalDataBufferLength =
1121                                         vmxferpagePacket->Ranges[i].ByteCount;
1122                 netvscPacket->PageBufferCount = 1;
1123
1124                 ASSERT(vmxferpagePacket->Ranges[i].ByteOffset +
1125                         vmxferpagePacket->Ranges[i].ByteCount <
1126                         netDevice->ReceiveBufferSize);
1127
1128                 netvscPacket->PageBuffers[0].Length =
1129                                         vmxferpagePacket->Ranges[i].ByteCount;
1130
1131                 start = virt_to_phys((void *)((unsigned long)netDevice->ReceiveBuffer + vmxferpagePacket->Ranges[i].ByteOffset));
1132
1133                 netvscPacket->PageBuffers[0].Pfn = start >> PAGE_SHIFT;
1134                 endVirtual = (unsigned long)netDevice->ReceiveBuffer
1135                     + vmxferpagePacket->Ranges[i].ByteOffset
1136                     + vmxferpagePacket->Ranges[i].ByteCount - 1;
1137                 end = virt_to_phys((void *)endVirtual);
1138
1139                 /* Calculate the page relative offset */
1140                 netvscPacket->PageBuffers[0].Offset =
1141                         vmxferpagePacket->Ranges[i].ByteOffset & (PAGE_SIZE - 1);
1142                 if ((end >> PAGE_SHIFT) != (start >> PAGE_SHIFT)) {
1143                         /* Handle frame across multiple pages: */
1144                         netvscPacket->PageBuffers[0].Length =
1145                                 (netvscPacket->PageBuffers[0].Pfn << PAGE_SHIFT)
1146                                 + PAGE_SIZE - start;
1147                         bytesRemain = netvscPacket->TotalDataBufferLength -
1148                                         netvscPacket->PageBuffers[0].Length;
1149                         for (j = 1; j < NETVSC_PACKET_MAXPAGE; j++) {
1150                                 netvscPacket->PageBuffers[j].Offset = 0;
1151                                 if (bytesRemain <= PAGE_SIZE) {
1152                                         netvscPacket->PageBuffers[j].Length = bytesRemain;
1153                                         bytesRemain = 0;
1154                                 } else {
1155                                         netvscPacket->PageBuffers[j].Length = PAGE_SIZE;
1156                                         bytesRemain -= PAGE_SIZE;
1157                                 }
1158                                 netvscPacket->PageBuffers[j].Pfn =
1159                                     virt_to_phys((void *)(endVirtual - bytesRemain)) >> PAGE_SHIFT;
1160                                 netvscPacket->PageBufferCount++;
1161                                 if (bytesRemain == 0)
1162                                         break;
1163                         }
1164                         ASSERT(bytesRemain == 0);
1165                 }
1166                 DPRINT_DBG(NETVSC, "[%d] - (abs offset %u len %u) => "
1167                            "(pfn %llx, offset %u, len %u)", i,
1168                            vmxferpagePacket->Ranges[i].ByteOffset,
1169                            vmxferpagePacket->Ranges[i].ByteCount,
1170                            netvscPacket->PageBuffers[0].Pfn,
1171                            netvscPacket->PageBuffers[0].Offset,
1172                            netvscPacket->PageBuffers[0].Length);
1173
1174                 /* Pass it to the upper layer */
1175                 ((struct netvsc_driver *)Device->Driver)->OnReceiveCallback(Device, netvscPacket);
1176
1177                 NetVscOnReceiveCompletion(netvscPacket->Completion.Recv.ReceiveCompletionContext);
1178         }
1179
1180         ASSERT(list_empty(&listHead));
1181
1182         PutNetDevice(Device);
1183         DPRINT_EXIT(NETVSC);
1184 }
1185
1186 static void NetVscSendReceiveCompletion(struct hv_device *Device,
1187                                         u64 TransactionId)
1188 {
1189         struct nvsp_message recvcompMessage;
1190         int retries = 0;
1191         int ret;
1192
1193         DPRINT_DBG(NETVSC, "Sending receive completion pkt - %llx",
1194                    TransactionId);
1195
1196         recvcompMessage.Header.MessageType =
1197                                 NvspMessage1TypeSendRNDISPacketComplete;
1198
1199         /* FIXME: Pass in the status */
1200         recvcompMessage.Messages.Version1Messages.SendRNDISPacketComplete.Status = NvspStatusSuccess;
1201
1202 retry_send_cmplt:
1203         /* Send the completion */
1204         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
1205                                         &recvcompMessage,
1206                                         sizeof(struct nvsp_message),
1207                                         TransactionId,
1208                                         VmbusPacketTypeCompletion, 0);
1209         if (ret == 0) {
1210                 /* success */
1211                 /* no-op */
1212         } else if (ret == -1) {
1213                 /* no more room...wait a bit and attempt to retry 3 times */
1214                 retries++;
1215                 DPRINT_ERR(NETVSC, "unable to send receive completion pkt "
1216                            "(tid %llx)...retrying %d", TransactionId, retries);
1217
1218                 if (retries < 4) {
1219                         udelay(100);
1220                         goto retry_send_cmplt;
1221                 } else {
1222                         DPRINT_ERR(NETVSC, "unable to send receive completion "
1223                                   "pkt (tid %llx)...give up retrying",
1224                                   TransactionId);
1225                 }
1226         } else {
1227                 DPRINT_ERR(NETVSC, "unable to send receive completion pkt - "
1228                            "%llx", TransactionId);
1229         }
1230 }
1231
1232 /* Send a receive completion packet to RNDIS device (ie NetVsp) */
1233 static void NetVscOnReceiveCompletion(void *Context)
1234 {
1235         struct hv_netvsc_packet *packet = Context;
1236         struct hv_device *device = (struct hv_device *)packet->Device;
1237         struct netvsc_device *netDevice;
1238         u64 transactionId = 0;
1239         bool fSendReceiveComp = false;
1240         unsigned long flags;
1241
1242         DPRINT_ENTER(NETVSC);
1243
1244         ASSERT(packet->XferPagePacket);
1245
1246         /*
1247          * Even though it seems logical to do a GetOutboundNetDevice() here to
1248          * send out receive completion, we are using GetInboundNetDevice()
1249          * since we may have disable outbound traffic already.
1250          */
1251         netDevice = GetInboundNetDevice(device);
1252         if (!netDevice) {
1253                 DPRINT_ERR(NETVSC, "unable to get net device..."
1254                            "device being destroyed?");
1255                 DPRINT_EXIT(NETVSC);
1256                 return;
1257         }
1258
1259         /* Overloading use of the lock. */
1260         spin_lock_irqsave(&netDevice->receive_packet_list_lock, flags);
1261
1262         ASSERT(packet->XferPagePacket->Count > 0);
1263         packet->XferPagePacket->Count--;
1264
1265         /*
1266          * Last one in the line that represent 1 xfer page packet.
1267          * Return the xfer page packet itself to the freelist
1268          */
1269         if (packet->XferPagePacket->Count == 0) {
1270                 fSendReceiveComp = true;
1271                 transactionId = packet->Completion.Recv.ReceiveCompletionTid;
1272                 list_add_tail(&packet->XferPagePacket->ListEntry,
1273                               &netDevice->ReceivePacketList);
1274
1275         }
1276
1277         /* Put the packet back */
1278         list_add_tail(&packet->ListEntry, &netDevice->ReceivePacketList);
1279         spin_unlock_irqrestore(&netDevice->receive_packet_list_lock, flags);
1280
1281         /* Send a receive completion for the xfer page packet */
1282         if (fSendReceiveComp)
1283                 NetVscSendReceiveCompletion(device, transactionId);
1284
1285         PutNetDevice(device);
1286         DPRINT_EXIT(NETVSC);
1287 }
1288
1289 void NetVscOnChannelCallback(void *Context)
1290 {
1291         const int netPacketSize = 2048;
1292         int ret;
1293         struct hv_device *device = Context;
1294         struct netvsc_device *netDevice;
1295         u32 bytesRecvd;
1296         u64 requestId;
1297         unsigned char packet[netPacketSize];
1298         struct vmpacket_descriptor *desc;
1299         unsigned char *buffer = packet;
1300         int bufferlen = netPacketSize;
1301
1302
1303         DPRINT_ENTER(NETVSC);
1304
1305         ASSERT(device);
1306
1307         netDevice = GetInboundNetDevice(device);
1308         if (!netDevice) {
1309                 DPRINT_ERR(NETVSC, "net device (%p) shutting down..."
1310                            "ignoring inbound packets", netDevice);
1311                 DPRINT_EXIT(NETVSC);
1312                 return;
1313         }
1314
1315         do {
1316                 ret = device->Driver->VmbusChannelInterface.RecvPacketRaw(
1317                                                 device, buffer, bufferlen,
1318                                                 &bytesRecvd, &requestId);
1319                 if (ret == 0) {
1320                         if (bytesRecvd > 0) {
1321                                 DPRINT_DBG(NETVSC, "receive %d bytes, tid %llx",
1322                                            bytesRecvd, requestId);
1323
1324                                 desc = (struct vmpacket_descriptor *)buffer;
1325                                 switch (desc->Type) {
1326                                 case VmbusPacketTypeCompletion:
1327                                         NetVscOnSendCompletion(device, desc);
1328                                         break;
1329
1330                                 case VmbusPacketTypeDataUsingTransferPages:
1331                                         NetVscOnReceive(device, desc);
1332                                         break;
1333
1334                                 default:
1335                                         DPRINT_ERR(NETVSC,
1336                                                    "unhandled packet type %d, "
1337                                                    "tid %llx len %d\n",
1338                                                    desc->Type, requestId,
1339                                                    bytesRecvd);
1340                                         break;
1341                                 }
1342
1343                                 /* reset */
1344                                 if (bufferlen > netPacketSize) {
1345                                         kfree(buffer);
1346                                         buffer = packet;
1347                                         bufferlen = netPacketSize;
1348                                 }
1349                         } else {
1350                                 /* reset */
1351                                 if (bufferlen > netPacketSize) {
1352                                         kfree(buffer);
1353                                         buffer = packet;
1354                                         bufferlen = netPacketSize;
1355                                 }
1356
1357                                 break;
1358                         }
1359                 } else if (ret == -2) {
1360                         /* Handle large packet */
1361                         buffer = kmalloc(bytesRecvd, GFP_ATOMIC);
1362                         if (buffer == NULL) {
1363                                 /* Try again next time around */
1364                                 DPRINT_ERR(NETVSC,
1365                                            "unable to allocate buffer of size "
1366                                            "(%d)!!", bytesRecvd);
1367                                 break;
1368                         }
1369
1370                         bufferlen = bytesRecvd;
1371                 } else {
1372                         ASSERT(0);
1373                 }
1374         } while (1);
1375
1376         PutNetDevice(device);
1377         DPRINT_EXIT(NETVSC);
1378         return;
1379 }