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