drivers/staging/hv/StorVsc.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/string.h>
  23 #include <linux/slab.h>
  24 #include <linux/mm.h>
  25 #include <linux/delay.h>
  26 #include "osd.h"
  27 #include "logging.h"
  28 #include "StorVscApi.h"
  29 #include "VmbusPacketFormat.h"
  30 #include "vstorage.h"
  31
  32
  33 struct storvsc_request_extension {
  34         /* LIST_ENTRY ListEntry; */
  35
  36         struct hv_storvsc_request *Request;
  37         struct hv_device *Device;
  38
  39         /* Synchronize the request/response if needed */
  40         struct osd_waitevent *WaitEvent;
  41
  42         struct vstor_packet VStorPacket;
  43 };
  44
  45 /* A storvsc device is a device object that contains a vmbus channel */
  46 struct storvsc_device {
  47         struct hv_device *Device;
  48
  49         /* 0 indicates the device is being destroyed */
  50         atomic_t RefCount;
  51
  52         atomic_t NumOutstandingRequests;
  53
  54         /*
  55          * Each unique Port/Path/Target represents 1 channel ie scsi
  56          * controller. In reality, the pathid, targetid is always 0
  57          * and the port is set by us
  58          */
  59         unsigned int PortNumber;
  60         unsigned char PathId;
  61         unsigned char TargetId;
  62
  63         /* LIST_ENTRY OutstandingRequestList; */
  64         /* HANDLE OutstandingRequestLock; */
  65
  66         /* Used for vsc/vsp channel reset process */
  67         struct storvsc_request_extension InitRequest;
  68         struct storvsc_request_extension ResetRequest;
  69 };
  70
  71
  72 static const char *gDriverName = "storvsc";
  73
  74 /* {ba6163d9-04a1-4d29-b605-72e2ffb1dc7f} */
  75 static const struct hv_guid gStorVscDeviceType = {
  76         .data = {
  77                 0xd9, 0x63, 0x61, 0xba, 0xa1, 0x04, 0x29, 0x4d,
  78                 0xb6, 0x05, 0x72, 0xe2, 0xff, 0xb1, 0xdc, 0x7f
  79         }
  80 };
  81
  82
  83 static inline struct storvsc_device *AllocStorDevice(struct hv_device *Device)
  84 {
  85         struct storvsc_device *storDevice;
  86
  87         storDevice = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
  88         if (!storDevice)
  89                 return NULL;
  90
  91         /* Set to 2 to allow both inbound and outbound traffics */
  92         /* (ie GetStorDevice() and MustGetStorDevice()) to proceed. */
  93         atomic_cmpxchg(&storDevice->RefCount, 0, 2);
  94
  95         storDevice->Device = Device;
  96         Device->Extension = storDevice;
  97
  98         return storDevice;
  99 }
 100
 101 static inline void FreeStorDevice(struct storvsc_device *Device)
 102 {
 103         ASSERT(atomic_read(&Device->RefCount) == 0);
 104         kfree(Device);
 105 }
 106
 107 /* Get the stordevice object iff exists and its refcount > 1 */
 108 static inline struct storvsc_device *GetStorDevice(struct hv_device *Device)
 109 {
 110         struct storvsc_device *storDevice;
 111
 112         storDevice = (struct storvsc_device *)Device->Extension;
 113         if (storDevice && atomic_read(&storDevice->RefCount) > 1)
 114                 atomic_inc(&storDevice->RefCount);
 115         else
 116                 storDevice = NULL;
 117
 118         return storDevice;
 119 }
 120
 121 /* Get the stordevice object iff exists and its refcount > 0 */
 122 static inline struct storvsc_device *MustGetStorDevice(struct hv_device *Device)
 123 {
 124         struct storvsc_device *storDevice;
 125
 126         storDevice = (struct storvsc_device *)Device->Extension;
 127         if (storDevice && atomic_read(&storDevice->RefCount))
 128                 atomic_inc(&storDevice->RefCount);
 129         else
 130                 storDevice = NULL;
 131
 132         return storDevice;
 133 }
 134
 135 static inline void PutStorDevice(struct hv_device *Device)
 136 {
 137         struct storvsc_device *storDevice;
 138
 139         storDevice = (struct storvsc_device *)Device->Extension;
 140         ASSERT(storDevice);
 141
 142         atomic_dec(&storDevice->RefCount);
 143         ASSERT(atomic_read(&storDevice->RefCount));
 144 }
 145
 146 /* Drop ref count to 1 to effectively disable GetStorDevice() */
 147 static inline struct storvsc_device *ReleaseStorDevice(struct hv_device *Device)
 148 {
 149         struct storvsc_device *storDevice;
 150
 151         storDevice = (struct storvsc_device *)Device->Extension;
 152         ASSERT(storDevice);
 153
 154         /* Busy wait until the ref drop to 2, then set it to 1 */
 155         while (atomic_cmpxchg(&storDevice->RefCount, 2, 1) != 2)
 156                 udelay(100);
 157
 158         return storDevice;
 159 }
 160
 161 /* Drop ref count to 0. No one can use StorDevice object. */
 162 static inline struct storvsc_device *FinalReleaseStorDevice(
 163                         struct hv_device *Device)
 164 {
 165         struct storvsc_device *storDevice;
 166
 167         storDevice = (struct storvsc_device *)Device->Extension;
 168         ASSERT(storDevice);
 169
 170         /* Busy wait until the ref drop to 1, then set it to 0 */
 171         while (atomic_cmpxchg(&storDevice->RefCount, 1, 0) != 1)
 172                 udelay(100);
 173
 174         Device->Extension = NULL;
 175         return storDevice;
 176 }
 177
 178 static int StorVscChannelInit(struct hv_device *Device)
 179 {
 180         struct storvsc_device *storDevice;
 181         struct storvsc_request_extension *request;
 182         struct vstor_packet *vstorPacket;
 183         int ret;
 184
 185         storDevice = GetStorDevice(Device);
 186         if (!storDevice) {
 187                 DPRINT_ERR(STORVSC, "unable to get stor device..."
 188                            "device being destroyed?");
 189                 DPRINT_EXIT(STORVSC);
 190                 return -1;
 191         }
 192
 193         request = &storDevice->InitRequest;
 194         vstorPacket = &request->VStorPacket;
 195
 196         /*
 197          * Now, initiate the vsc/vsp initialization protocol on the open
 198          * channel
 199          */
 200         memset(request, 0, sizeof(struct storvsc_request_extension));
 201         request->WaitEvent = osd_WaitEventCreate();
 202
 203         vstorPacket->Operation = VStorOperationBeginInitialization;
 204         vstorPacket->Flags = REQUEST_COMPLETION_FLAG;
 205
 206         /*SpinlockAcquire(gDriverExt.packetListLock);
 207         INSERT_TAIL_LIST(&gDriverExt.packetList, &packet->listEntry.entry);
 208         SpinlockRelease(gDriverExt.packetListLock);*/
 209
 210         DPRINT_INFO(STORVSC, "BEGIN_INITIALIZATION_OPERATION...");
 211
 212         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 213                                 vstorPacket,
 214                                 sizeof(struct vstor_packet),
 215                                 (unsigned long)request,
 216                                 VmbusPacketTypeDataInBand,
 217                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 218         if (ret != 0) {
 219                 DPRINT_ERR(STORVSC,
 220                            "unable to send BEGIN_INITIALIZATION_OPERATION");
 221                 goto Cleanup;
 222         }
 223
 224         osd_WaitEventWait(request->WaitEvent);
 225
 226         if (vstorPacket->Operation != VStorOperationCompleteIo ||
 227             vstorPacket->Status != 0) {
 228                 DPRINT_ERR(STORVSC, "BEGIN_INITIALIZATION_OPERATION failed "
 229                            "(op %d status 0x%x)",
 230                            vstorPacket->Operation, vstorPacket->Status);
 231                 goto Cleanup;
 232         }
 233
 234         DPRINT_INFO(STORVSC, "QUERY_PROTOCOL_VERSION_OPERATION...");
 235
 236         /* reuse the packet for version range supported */
 237         memset(vstorPacket, 0, sizeof(struct vstor_packet));
 238         vstorPacket->Operation = VStorOperationQueryProtocolVersion;
 239         vstorPacket->Flags = REQUEST_COMPLETION_FLAG;
 240
 241         vstorPacket->Version.MajorMinor = VMSTOR_PROTOCOL_VERSION_CURRENT;
 242         FILL_VMSTOR_REVISION(vstorPacket->Version.Revision);
 243
 244         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 245                                 vstorPacket,
 246                                 sizeof(struct vstor_packet),
 247                                 (unsigned long)request,
 248                                 VmbusPacketTypeDataInBand,
 249                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 250         if (ret != 0) {
 251                 DPRINT_ERR(STORVSC,
 252                            "unable to send BEGIN_INITIALIZATION_OPERATION");
 253                 goto Cleanup;
 254         }
 255
 256         osd_WaitEventWait(request->WaitEvent);
 257
 258         /* TODO: Check returned version */
 259         if (vstorPacket->Operation != VStorOperationCompleteIo ||
 260             vstorPacket->Status != 0) {
 261                 DPRINT_ERR(STORVSC, "QUERY_PROTOCOL_VERSION_OPERATION failed "
 262                            "(op %d status 0x%x)",
 263                            vstorPacket->Operation, vstorPacket->Status);
 264                 goto Cleanup;
 265         }
 266
 267         /* Query channel properties */
 268         DPRINT_INFO(STORVSC, "QUERY_PROPERTIES_OPERATION...");
 269
 270         memset(vstorPacket, 0, sizeof(struct vstor_packet));
 271         vstorPacket->Operation = VStorOperationQueryProperties;
 272         vstorPacket->Flags = REQUEST_COMPLETION_FLAG;
 273         vstorPacket->StorageChannelProperties.PortNumber =
 274                                         storDevice->PortNumber;
 275
 276         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 277                                 vstorPacket,
 278                                 sizeof(struct vstor_packet),
 279                                 (unsigned long)request,
 280                                 VmbusPacketTypeDataInBand,
 281                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 282
 283         if (ret != 0) {
 284                 DPRINT_ERR(STORVSC,
 285                            "unable to send QUERY_PROPERTIES_OPERATION");
 286                 goto Cleanup;
 287         }
 288
 289         osd_WaitEventWait(request->WaitEvent);
 290
 291         /* TODO: Check returned version */
 292         if (vstorPacket->Operation != VStorOperationCompleteIo ||
 293             vstorPacket->Status != 0) {
 294                 DPRINT_ERR(STORVSC, "QUERY_PROPERTIES_OPERATION failed "
 295                            "(op %d status 0x%x)",
 296                            vstorPacket->Operation, vstorPacket->Status);
 297                 goto Cleanup;
 298         }
 299
 300         storDevice->PathId = vstorPacket->StorageChannelProperties.PathId;
 301         storDevice->TargetId = vstorPacket->StorageChannelProperties.TargetId;
 302
 303         DPRINT_DBG(STORVSC, "channel flag 0x%x, max xfer len 0x%x",
 304                    vstorPacket->StorageChannelProperties.Flags,
 305                    vstorPacket->StorageChannelProperties.MaxTransferBytes);
 306
 307         DPRINT_INFO(STORVSC, "END_INITIALIZATION_OPERATION...");
 308
 309         memset(vstorPacket, 0, sizeof(struct vstor_packet));
 310         vstorPacket->Operation = VStorOperationEndInitialization;
 311         vstorPacket->Flags = REQUEST_COMPLETION_FLAG;
 312
 313         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 314                                 vstorPacket,
 315                                 sizeof(struct vstor_packet),
 316                                 (unsigned long)request,
 317                                 VmbusPacketTypeDataInBand,
 318                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 319
 320         if (ret != 0) {
 321                 DPRINT_ERR(STORVSC,
 322                            "unable to send END_INITIALIZATION_OPERATION");
 323                 goto Cleanup;
 324         }
 325
 326         osd_WaitEventWait(request->WaitEvent);
 327
 328         if (vstorPacket->Operation != VStorOperationCompleteIo ||
 329             vstorPacket->Status != 0) {
 330                 DPRINT_ERR(STORVSC, "END_INITIALIZATION_OPERATION failed "
 331                            "(op %d status 0x%x)",
 332                            vstorPacket->Operation, vstorPacket->Status);
 333                 goto Cleanup;
 334         }
 335
 336         DPRINT_INFO(STORVSC, "**** storage channel up and running!! ****");
 337
 338 Cleanup:
 339         kfree(request->WaitEvent);
 340         request->WaitEvent = NULL;
 341
 342         PutStorDevice(Device);
 343
 344         DPRINT_EXIT(STORVSC);
 345         return ret;
 346 }
 347
 348 static void StorVscOnIOCompletion(struct hv_device *Device,
 349                                   struct vstor_packet *VStorPacket,
 350                                   struct storvsc_request_extension *RequestExt)
 351 {
 352         struct hv_storvsc_request *request;
 353         struct storvsc_device *storDevice;
 354
 355         DPRINT_ENTER(STORVSC);
 356
 357         storDevice = MustGetStorDevice(Device);
 358         if (!storDevice) {
 359                 DPRINT_ERR(STORVSC, "unable to get stor device..."
 360                            "device being destroyed?");
 361                 DPRINT_EXIT(STORVSC);
 362                 return;
 363         }
 364
 365         DPRINT_DBG(STORVSC, "IO_COMPLETE_OPERATION - request extension %p "
 366                    "completed bytes xfer %u", RequestExt,
 367                    VStorPacket->VmSrb.DataTransferLength);
 368
 369         ASSERT(RequestExt != NULL);
 370         ASSERT(RequestExt->Request != NULL);
 371
 372         request = RequestExt->Request;
 373
 374         ASSERT(request->OnIOCompletion != NULL);
 375
 376         /* Copy over the status...etc */
 377         request->Status = VStorPacket->VmSrb.ScsiStatus;
 378
 379         if (request->Status != 0 || VStorPacket->VmSrb.SrbStatus != 1) {
 380                 DPRINT_WARN(STORVSC,
 381                             "cmd 0x%x scsi status 0x%x srb status 0x%x\n",
 382                             request->Cdb[0], VStorPacket->VmSrb.ScsiStatus,
 383                             VStorPacket->VmSrb.SrbStatus);
 384         }
 385
 386         if ((request->Status & 0xFF) == 0x02) {
 387                 /* CHECK_CONDITION */
 388                 if (VStorPacket->VmSrb.SrbStatus & 0x80) {
 389                         /* autosense data available */
 390                         DPRINT_WARN(STORVSC, "storvsc pkt %p autosense data "
 391                                     "valid - len %d\n", RequestExt,
 392                                     VStorPacket->VmSrb.SenseInfoLength);
 393
 394                         ASSERT(VStorPacket->VmSrb.SenseInfoLength <=
 395                                 request->SenseBufferSize);
 396                         memcpy(request->SenseBuffer,
 397                                VStorPacket->VmSrb.SenseData,
 398                                VStorPacket->VmSrb.SenseInfoLength);
 399
 400                         request->SenseBufferSize =
 401                                         VStorPacket->VmSrb.SenseInfoLength;
 402                 }
 403         }
 404
 405         /* TODO: */
 406         request->BytesXfer = VStorPacket->VmSrb.DataTransferLength;
 407
 408         request->OnIOCompletion(request);
 409
 410         atomic_dec(&storDevice->NumOutstandingRequests);
 411
 412         PutStorDevice(Device);
 413
 414         DPRINT_EXIT(STORVSC);
 415 }
 416
 417 static void StorVscOnReceive(struct hv_device *Device,
 418                              struct vstor_packet *VStorPacket,
 419                              struct storvsc_request_extension *RequestExt)
 420 {
 421         switch (VStorPacket->Operation) {
 422         case VStorOperationCompleteIo:
 423                 DPRINT_DBG(STORVSC, "IO_COMPLETE_OPERATION");
 424                 StorVscOnIOCompletion(Device, VStorPacket, RequestExt);
 425                 break;
 426         case VStorOperationRemoveDevice:
 427                 DPRINT_INFO(STORVSC, "REMOVE_DEVICE_OPERATION");
 428                 /* TODO: */
 429                 break;
 430
 431         default:
 432                 DPRINT_INFO(STORVSC, "Unknown operation received - %d",
 433                             VStorPacket->Operation);
 434                 break;
 435         }
 436 }
 437
 438 static void StorVscOnChannelCallback(void *context)
 439 {
 440         struct hv_device *device = (struct hv_device *)context;
 441         struct storvsc_device *storDevice;
 442         u32 bytesRecvd;
 443         u64 requestId;
 444         unsigned char packet[ALIGN_UP(sizeof(struct vstor_packet), 8)];
 445         struct storvsc_request_extension *request;
 446         int ret;
 447
 448         DPRINT_ENTER(STORVSC);
 449
 450         ASSERT(device);
 451
 452         storDevice = MustGetStorDevice(device);
 453         if (!storDevice) {
 454                 DPRINT_ERR(STORVSC, "unable to get stor device..."
 455                            "device being destroyed?");
 456                 DPRINT_EXIT(STORVSC);
 457                 return;
 458         }
 459
 460         do {
 461                 ret = device->Driver->VmbusChannelInterface.RecvPacket(device,
 462                                 packet,
 463                                 ALIGN_UP(sizeof(struct vstor_packet), 8),
 464                                 &bytesRecvd, &requestId);
 465                 if (ret == 0 && bytesRecvd > 0) {
 466                         DPRINT_DBG(STORVSC, "receive %d bytes - tid %llx",
 467                                    bytesRecvd, requestId);
 468
 469                         /* ASSERT(bytesRecvd == sizeof(struct vstor_packet)); */
 470
 471                         request = (struct storvsc_request_extension *)
 472                                         (unsigned long)requestId;
 473                         ASSERT(request);
 474
 475                         /* if (vstorPacket.Flags & SYNTHETIC_FLAG) */
 476                         if ((request == &storDevice->InitRequest) ||
 477                             (request == &storDevice->ResetRequest)) {
 478                                 /* DPRINT_INFO(STORVSC,
 479                                  *             "reset completion - operation "
 480                                  *             "%u status %u",
 481                                  *             vstorPacket.Operation,
 482                                  *             vstorPacket.Status); */
 483
 484                                 memcpy(&request->VStorPacket, packet,
 485                                        sizeof(struct vstor_packet));
 486
 487                                 osd_WaitEventSet(request->WaitEvent);
 488                         } else {
 489                                 StorVscOnReceive(device,
 490                                                 (struct vstor_packet *)packet,
 491                                                 request);
 492                         }
 493                 } else {
 494                         /* DPRINT_DBG(STORVSC, "nothing else to read..."); */
 495                         break;
 496                 }
 497         } while (1);
 498
 499         PutStorDevice(device);
 500
 501         DPRINT_EXIT(STORVSC);
 502         return;
 503 }
 504
 505 static int StorVscConnectToVsp(struct hv_device *Device)
 506 {
 507         struct vmstorage_channel_properties props;
 508         struct storvsc_driver_object *storDriver;
 509         int ret;
 510
 511         storDriver = (struct storvsc_driver_object *)Device->Driver;
 512         memset(&props, 0, sizeof(struct vmstorage_channel_properties));
 513
 514         /* Open the channel */
 515         ret = Device->Driver->VmbusChannelInterface.Open(Device,
 516                         storDriver->RingBufferSize,
 517                         storDriver->RingBufferSize,
 518                         (void *)&props,
 519                         sizeof(struct vmstorage_channel_properties),
 520                         StorVscOnChannelCallback,
 521                         Device);
 522
 523         DPRINT_DBG(STORVSC, "storage props: path id %d, tgt id %d, max xfer %d",
 524                    props.PathId, props.TargetId, props.MaxTransferBytes);
 525
 526         if (ret != 0) {
 527                 DPRINT_ERR(STORVSC, "unable to open channel: %d", ret);
 528                 return -1;
 529         }
 530
 531         ret = StorVscChannelInit(Device);
 532
 533         return ret;
 534 }
 535
 536 /**
 537  * StorVscOnDeviceAdd - Callback when the device belonging to this driver is added
 538  */
 539 static int StorVscOnDeviceAdd(struct hv_device *Device, void *AdditionalInfo)
 540 {
 541         struct storvsc_device *storDevice;
 542         /* struct vmstorage_channel_properties *props; */
 543         struct storvsc_device_info *deviceInfo;
 544         int ret = 0;
 545
 546         DPRINT_ENTER(STORVSC);
 547
 548         deviceInfo = (struct storvsc_device_info *)AdditionalInfo;
 549         storDevice = AllocStorDevice(Device);
 550         if (!storDevice) {
 551                 ret = -1;
 552                 goto Cleanup;
 553         }
 554
 555         /* Save the channel properties to our storvsc channel */
 556         /* props = (struct vmstorage_channel_properties *)
 557          *              channel->offerMsg.Offer.u.Standard.UserDefined; */
 558
 559         /* FIXME: */
 560         /*
 561          * If we support more than 1 scsi channel, we need to set the
 562          * port number here to the scsi channel but how do we get the
 563          * scsi channel prior to the bus scan
 564          */
 565
 566         /* storChannel->PortNumber = 0;
 567         storChannel->PathId = props->PathId;
 568         storChannel->TargetId = props->TargetId; */
 569
 570         storDevice->PortNumber = deviceInfo->PortNumber;
 571         /* Send it back up */
 572         ret = StorVscConnectToVsp(Device);
 573
 574         /* deviceInfo->PortNumber = storDevice->PortNumber; */
 575         deviceInfo->PathId = storDevice->PathId;
 576         deviceInfo->TargetId = storDevice->TargetId;
 577
 578         DPRINT_DBG(STORVSC, "assigned port %u, path %u target %u\n",
 579                    storDevice->PortNumber, storDevice->PathId,
 580                    storDevice->TargetId);
 581
 582 Cleanup:
 583         DPRINT_EXIT(STORVSC);
 584
 585         return ret;
 586 }
 587
 588 /**
 589  * StorVscOnDeviceRemove - Callback when the our device is being removed
 590  */
 591 static int StorVscOnDeviceRemove(struct hv_device *Device)
 592 {
 593         struct storvsc_device *storDevice;
 594
 595         DPRINT_ENTER(STORVSC);
 596
 597         DPRINT_INFO(STORVSC, "disabling storage device (%p)...",
 598                     Device->Extension);
 599
 600         storDevice = ReleaseStorDevice(Device);
 601
 602         /*
 603          * At this point, all outbound traffic should be disable. We
 604          * only allow inbound traffic (responses) to proceed so that
 605          * outstanding requests can be completed.
 606          */
 607         while (atomic_read(&storDevice->NumOutstandingRequests)) {
 608                 DPRINT_INFO(STORVSC, "waiting for %d requests to complete...",
 609                             atomic_read(&storDevice->NumOutstandingRequests));
 610                 udelay(100);
 611         }
 612
 613         DPRINT_INFO(STORVSC, "removing storage device (%p)...",
 614                     Device->Extension);
 615
 616         storDevice = FinalReleaseStorDevice(Device);
 617
 618         DPRINT_INFO(STORVSC, "storage device (%p) safe to remove", storDevice);
 619
 620         /* Close the channel */
 621         Device->Driver->VmbusChannelInterface.Close(Device);
 622
 623         FreeStorDevice(storDevice);
 624
 625         DPRINT_EXIT(STORVSC);
 626         return 0;
 627 }
 628
 629 int StorVscOnHostReset(struct hv_device *Device)
 630 {
 631         struct storvsc_device *storDevice;
 632         struct storvsc_request_extension *request;
 633         struct vstor_packet *vstorPacket;
 634         int ret;
 635
 636         DPRINT_ENTER(STORVSC);
 637
 638         DPRINT_INFO(STORVSC, "resetting host adapter...");
 639
 640         storDevice = GetStorDevice(Device);
 641         if (!storDevice) {
 642                 DPRINT_ERR(STORVSC, "unable to get stor device..."
 643                            "device being destroyed?");
 644                 DPRINT_EXIT(STORVSC);
 645                 return -1;
 646         }
 647
 648         request = &storDevice->ResetRequest;
 649         vstorPacket = &request->VStorPacket;
 650
 651         request->WaitEvent = osd_WaitEventCreate();
 652
 653         vstorPacket->Operation = VStorOperationResetBus;
 654         vstorPacket->Flags = REQUEST_COMPLETION_FLAG;
 655         vstorPacket->VmSrb.PathId = storDevice->PathId;
 656
 657         ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 658                                 vstorPacket,
 659                                 sizeof(struct vstor_packet),
 660                                 (unsigned long)&storDevice->ResetRequest,
 661                                 VmbusPacketTypeDataInBand,
 662                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 663         if (ret != 0) {
 664                 DPRINT_ERR(STORVSC, "Unable to send reset packet %p ret %d",
 665                            vstorPacket, ret);
 666                 goto Cleanup;
 667         }
 668
 669         /* FIXME: Add a timeout */
 670         osd_WaitEventWait(request->WaitEvent);
 671
 672         kfree(request->WaitEvent);
 673         DPRINT_INFO(STORVSC, "host adapter reset completed");
 674
 675         /*
 676          * At this point, all outstanding requests in the adapter
 677          * should have been flushed out and return to us
 678          */
 679
 680 Cleanup:
 681         PutStorDevice(Device);
 682         DPRINT_EXIT(STORVSC);
 683         return ret;
 684 }
 685
 686 /**
 687  * StorVscOnIORequest - Callback to initiate an I/O request
 688  */
 689 static int StorVscOnIORequest(struct hv_device *Device,
 690                               struct hv_storvsc_request *Request)
 691 {
 692         struct storvsc_device *storDevice;
 693         struct storvsc_request_extension *requestExtension;
 694         struct vstor_packet *vstorPacket;
 695         int ret = 0;
 696
 697         DPRINT_ENTER(STORVSC);
 698
 699         requestExtension =
 700                 (struct storvsc_request_extension *)Request->Extension;
 701         vstorPacket = &requestExtension->VStorPacket;
 702         storDevice = GetStorDevice(Device);
 703
 704         DPRINT_DBG(STORVSC, "enter - Device %p, DeviceExt %p, Request %p, "
 705                    "Extension %p", Device, storDevice, Request,
 706                    requestExtension);
 707
 708         DPRINT_DBG(STORVSC, "req %p len %d bus %d, target %d, lun %d cdblen %d",
 709                    Request, Request->DataBuffer.Length, Request->Bus,
 710                    Request->TargetId, Request->LunId, Request->CdbLen);
 711
 712         if (!storDevice) {
 713                 DPRINT_ERR(STORVSC, "unable to get stor device..."
 714                            "device being destroyed?");
 715                 DPRINT_EXIT(STORVSC);
 716                 return -2;
 717         }
 718
 719         /* print_hex_dump_bytes("", DUMP_PREFIX_NONE, Request->Cdb,
 720          *                      Request->CdbLen); */
 721
 722         requestExtension->Request = Request;
 723         requestExtension->Device  = Device;
 724
 725         memset(vstorPacket, 0 , sizeof(struct vstor_packet));
 726
 727         vstorPacket->Flags |= REQUEST_COMPLETION_FLAG;
 728
 729         vstorPacket->VmSrb.Length = sizeof(struct vmscsi_request);
 730
 731         vstorPacket->VmSrb.PortNumber = Request->Host;
 732         vstorPacket->VmSrb.PathId = Request->Bus;
 733         vstorPacket->VmSrb.TargetId = Request->TargetId;
 734         vstorPacket->VmSrb.Lun = Request->LunId;
 735
 736         vstorPacket->VmSrb.SenseInfoLength = SENSE_BUFFER_SIZE;
 737
 738         /* Copy over the scsi command descriptor block */
 739         vstorPacket->VmSrb.CdbLength = Request->CdbLen;
 740         memcpy(&vstorPacket->VmSrb.Cdb, Request->Cdb, Request->CdbLen);
 741
 742         vstorPacket->VmSrb.DataIn = Request->Type;
 743         vstorPacket->VmSrb.DataTransferLength = Request->DataBuffer.Length;
 744
 745         vstorPacket->Operation = VStorOperationExecuteSRB;
 746
 747         DPRINT_DBG(STORVSC, "srb - len %d port %d, path %d, target %d, "
 748                    "lun %d senselen %d cdblen %d",
 749                    vstorPacket->VmSrb.Length,
 750                    vstorPacket->VmSrb.PortNumber,
 751                    vstorPacket->VmSrb.PathId,
 752                    vstorPacket->VmSrb.TargetId,
 753                    vstorPacket->VmSrb.Lun,
 754                    vstorPacket->VmSrb.SenseInfoLength,
 755                    vstorPacket->VmSrb.CdbLength);
 756
 757         if (requestExtension->Request->DataBuffer.Length) {
 758                 ret = Device->Driver->VmbusChannelInterface.
 759                         SendPacketMultiPageBuffer(Device,
 760                                 &requestExtension->Request->DataBuffer,
 761                                 vstorPacket,
 762                                 sizeof(struct vstor_packet),
 763                                 (unsigned long)requestExtension);
 764         } else {
 765                 ret = Device->Driver->VmbusChannelInterface.SendPacket(Device,
 766                                 vstorPacket,
 767                                 sizeof(struct vstor_packet),
 768                                 (unsigned long)requestExtension,
 769                                 VmbusPacketTypeDataInBand,
 770                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 771         }
 772
 773         if (ret != 0) {
 774                 DPRINT_DBG(STORVSC, "Unable to send packet %p ret %d",
 775                            vstorPacket, ret);
 776         }
 777
 778         atomic_inc(&storDevice->NumOutstandingRequests);
 779
 780         PutStorDevice(Device);
 781
 782         DPRINT_EXIT(STORVSC);
 783         return ret;
 784 }
 785
 786 /**
 787  * StorVscOnCleanup - Perform any cleanup when the driver is removed
 788  */
 789 static void StorVscOnCleanup(struct hv_driver *Driver)
 790 {
 791         DPRINT_ENTER(STORVSC);
 792         DPRINT_EXIT(STORVSC);
 793 }
 794
 795 /**
 796  * StorVscInitialize - Main entry point
 797  */
 798 int StorVscInitialize(struct hv_driver *Driver)
 799 {
 800         struct storvsc_driver_object *storDriver;
 801
 802         DPRINT_ENTER(STORVSC);
 803
 804         storDriver = (struct storvsc_driver_object *)Driver;
 805
 806         DPRINT_DBG(STORVSC, "sizeof(STORVSC_REQUEST)=%zd "
 807                    "sizeof(struct storvsc_request_extension)=%zd "
 808                    "sizeof(struct vstor_packet)=%zd, "
 809                    "sizeof(struct vmscsi_request)=%zd",
 810                    sizeof(struct hv_storvsc_request),
 811                    sizeof(struct storvsc_request_extension),
 812                    sizeof(struct vstor_packet),
 813                    sizeof(struct vmscsi_request));
 814
 815         /* Make sure we are at least 2 pages since 1 page is used for control */
 816         ASSERT(storDriver->RingBufferSize >= (PAGE_SIZE << 1));
 817
 818         Driver->name = gDriverName;
 819         memcpy(&Driver->deviceType, &gStorVscDeviceType,
 820                sizeof(struct hv_guid));
 821
 822         storDriver->RequestExtSize = sizeof(struct storvsc_request_extension);
 823
 824         /*
 825          * Divide the ring buffer data size (which is 1 page less
 826          * than the ring buffer size since that page is reserved for
 827          * the ring buffer indices) by the max request size (which is
 828          * VMBUS_CHANNEL_PACKET_MULITPAGE_BUFFER + struct vstor_packet + u64)
 829          */
 830         storDriver->MaxOutstandingRequestsPerChannel =
 831                 ((storDriver->RingBufferSize - PAGE_SIZE) /
 832                   ALIGN_UP(MAX_MULTIPAGE_BUFFER_PACKET +
 833                            sizeof(struct vstor_packet) + sizeof(u64),
 834                            sizeof(u64)));
 835
 836         DPRINT_INFO(STORVSC, "max io %u, currently %u\n",
 837                     storDriver->MaxOutstandingRequestsPerChannel,
 838                     STORVSC_MAX_IO_REQUESTS);
 839
 840         /* Setup the dispatch table */
 841         storDriver->Base.OnDeviceAdd    = StorVscOnDeviceAdd;
 842         storDriver->Base.OnDeviceRemove = StorVscOnDeviceRemove;
 843         storDriver->Base.OnCleanup      = StorVscOnCleanup;
 844
 845         storDriver->OnIORequest         = StorVscOnIORequest;
 846
 847         DPRINT_EXIT(STORVSC);
 848
 849         return 0;
 850 }