ntoskrnl/io/iomgr/iomgr.c

   1 /*
   2  * COPYRIGHT:       See COPYING in the top level directory
   3  * PROJECT:         ReactOS Kernel
   4  * FILE:            ntoskrnl/io/iomgr.c
   5  * PURPOSE:         I/O Manager Initialization and Misc Utility Functions
   6  *
   7  * PROGRAMMERS:     David Welch (welch@mcmail.com)
   8  */
   9
  10 /* INCLUDES ****************************************************************/
  11
  12 #include <ntoskrnl.h>
  13 #define NDEBUG
  14 #include <debug.h>
  15
  16 ULONG IopTraceLevel = 0;
  17 BOOLEAN PnpSystemInit = FALSE;
  18
  19 VOID
  20 NTAPI
  21 IopTimerDispatch(
  22     IN PKDPC Dpc,
  23     IN PVOID DeferredContext,
  24     IN PVOID SystemArgument1,
  25     IN PVOID SystemArgument2
  26 );
  27
  28 /* DATA ********************************************************************/
  29
  30 POBJECT_TYPE IoDeviceObjectType = NULL;
  31 POBJECT_TYPE IoFileObjectType = NULL;
  32 extern POBJECT_TYPE IoControllerObjectType;
  33 extern UNICODE_STRING NtSystemRoot;
  34 BOOLEAN IoCountOperations = TRUE;
  35 ULONG IoReadOperationCount = 0;
  36 LARGE_INTEGER IoReadTransferCount = {{0, 0}};
  37 ULONG IoWriteOperationCount = 0;
  38 LARGE_INTEGER IoWriteTransferCount = {{0, 0}};
  39 ULONG IoOtherOperationCount = 0;
  40 LARGE_INTEGER IoOtherTransferCount = {{0, 0}};
  41 KSPIN_LOCK IoStatisticsLock = 0;
  42 ULONG IopNumTriageDumpDataBlocks;
  43 PVOID IopTriageDumpDataBlocks[64];
  44
  45 GENERIC_MAPPING IopFileMapping = {
  46     FILE_GENERIC_READ,
  47     FILE_GENERIC_WRITE,
  48     FILE_GENERIC_EXECUTE,
  49     FILE_ALL_ACCESS};
  50
  51 extern LIST_ENTRY ShutdownListHead;
  52 extern LIST_ENTRY LastChanceShutdownListHead;
  53 extern KSPIN_LOCK ShutdownListLock;
  54 extern POBJECT_TYPE IoAdapterObjectType;
  55 extern ERESOURCE IopDatabaseResource;
  56 ERESOURCE IopSecurityResource;
  57 extern KGUARDED_MUTEX PnpNotifyListLock;
  58 extern LIST_ENTRY IopDiskFileSystemQueueHead;
  59 extern LIST_ENTRY IopCdRomFileSystemQueueHead;
  60 extern LIST_ENTRY IopTapeFileSystemQueueHead;
  61 extern LIST_ENTRY IopNetworkFileSystemQueueHead;
  62 extern LIST_ENTRY DriverBootReinitListHead;
  63 extern LIST_ENTRY DriverReinitListHead;
  64 extern LIST_ENTRY PnpNotifyListHead;
  65 extern LIST_ENTRY IopFsNotifyChangeQueueHead;
  66 extern LIST_ENTRY IopErrorLogListHead;
  67 extern LIST_ENTRY IopTimerQueueHead;
  68 extern KDPC IopTimerDpc;
  69 extern KTIMER IopTimer;
  70 extern KSPIN_LOCK IoStatisticsLock;
  71 extern KSPIN_LOCK DriverReinitListLock;
  72 extern KSPIN_LOCK DriverBootReinitListLock;
  73 extern KSPIN_LOCK IopLogListLock;
  74 extern KSPIN_LOCK IopTimerLock;
  75
  76 extern PDEVICE_OBJECT IopErrorLogObject;
  77
  78 GENERAL_LOOKASIDE IoLargeIrpLookaside;
  79 GENERAL_LOOKASIDE IoSmallIrpLookaside;
  80 GENERAL_LOOKASIDE IopMdlLookasideList;
  81 extern GENERAL_LOOKASIDE IoCompletionPacketLookaside;
  82
  83 PLOADER_PARAMETER_BLOCK IopLoaderBlock;
  84
  85 #if defined (ALLOC_PRAGMA)
  86 #pragma alloc_text(INIT, IoInitSystem)
  87 #endif
  88
  89 /* INIT FUNCTIONS ************************************************************/
  90
  91 VOID
  92 INIT_FUNCTION
  93 NTAPI
  94 IopInitLookasideLists(VOID)
  95 {
  96     ULONG LargeIrpSize, SmallIrpSize, MdlSize;
  97     LONG i;
  98     PKPRCB Prcb;
  99     PGENERAL_LOOKASIDE CurrentList = NULL;
 100
 101     /* Calculate the sizes */
 102     LargeIrpSize = sizeof(IRP) + (8 * sizeof(IO_STACK_LOCATION));
 103     SmallIrpSize = sizeof(IRP) + sizeof(IO_STACK_LOCATION);
 104     MdlSize = sizeof(MDL) + (23 * sizeof(PFN_NUMBER));
 105
 106     /* Initialize the Lookaside List for I\O Completion */
 107     ExInitializeSystemLookasideList(&IoCompletionPacketLookaside,
 108                                     NonPagedPool,
 109                                     sizeof(IOP_MINI_COMPLETION_PACKET),
 110                                     IOC_TAG1,
 111                                     32,
 112                                     &ExSystemLookasideListHead);
 113
 114     /* Initialize the Lookaside List for Large IRPs */
 115     ExInitializeSystemLookasideList(&IoLargeIrpLookaside,
 116                                     NonPagedPool,
 117                                     LargeIrpSize,
 118                                     IO_LARGEIRP,
 119                                     64,
 120                                     &ExSystemLookasideListHead);
 121
 122
 123     /* Initialize the Lookaside List for Small IRPs */
 124     ExInitializeSystemLookasideList(&IoSmallIrpLookaside,
 125                                     NonPagedPool,
 126                                     SmallIrpSize,
 127                                     IO_SMALLIRP,
 128                                     32,
 129                                     &ExSystemLookasideListHead);
 130
 131     /* Initialize the Lookaside List for MDLs */
 132     ExInitializeSystemLookasideList(&IopMdlLookasideList,
 133                                     NonPagedPool,
 134                                     MdlSize,
 135                                     TAG_MDL,
 136                                     128,
 137                                     &ExSystemLookasideListHead);
 138
 139     /* Allocate the global lookaside list buffer */
 140     CurrentList = ExAllocatePoolWithTag(NonPagedPool,
 141                                         4 * KeNumberProcessors *
 142                                         sizeof(GENERAL_LOOKASIDE),
 143                                         TAG_IO);
 144
 145     /* Loop all processors */
 146     for (i = 0; i < KeNumberProcessors; i++)
 147     {
 148         /* Get the PRCB for this CPU */
 149         Prcb = KiProcessorBlock[i];
 150         DPRINT("Setting up lookaside for CPU: %x, PRCB: %p\n", i, Prcb);
 151
 152         /* Write IRP credit limit */
 153         Prcb->LookasideIrpFloat = 512 / KeNumberProcessors;
 154
 155         /* Set the I/O Completion List */
 156         Prcb->PPLookasideList[LookasideCompletionList].L = &IoCompletionPacketLookaside;
 157         if (CurrentList)
 158         {
 159             /* Initialize the Lookaside List for mini-packets */
 160             ExInitializeSystemLookasideList(CurrentList,
 161                                             NonPagedPool,
 162                                             sizeof(IOP_MINI_COMPLETION_PACKET),
 163                                             IO_SMALLIRP_CPU,
 164                                             32,
 165                                             &ExSystemLookasideListHead);
 166             Prcb->PPLookasideList[LookasideCompletionList].P = CurrentList;
 167             CurrentList++;
 168
 169         }
 170         else
 171         {
 172             Prcb->PPLookasideList[LookasideCompletionList].P = &IoCompletionPacketLookaside;
 173         }
 174
 175         /* Set the Large IRP List */
 176         Prcb->PPLookasideList[LookasideLargeIrpList].L = &IoLargeIrpLookaside;
 177         if (CurrentList)
 178         {
 179             /* Initialize the Lookaside List for Large IRPs */
 180             ExInitializeSystemLookasideList(CurrentList,
 181                                             NonPagedPool,
 182                                             LargeIrpSize,
 183                                             IO_LARGEIRP_CPU,
 184                                             64,
 185                                             &ExSystemLookasideListHead);
 186             Prcb->PPLookasideList[LookasideLargeIrpList].P = CurrentList;
 187             CurrentList++;
 188
 189         }
 190         else
 191         {
 192             Prcb->PPLookasideList[LookasideLargeIrpList].P = &IoLargeIrpLookaside;
 193         }
 194
 195         /* Set the Small IRP List */
 196         Prcb->PPLookasideList[LookasideSmallIrpList].L = &IoSmallIrpLookaside;
 197         if (CurrentList)
 198         {
 199             /* Initialize the Lookaside List for Small IRPs */
 200             ExInitializeSystemLookasideList(CurrentList,
 201                                             NonPagedPool,
 202                                             SmallIrpSize,
 203                                             IO_SMALLIRP_CPU,
 204                                             32,
 205                                             &ExSystemLookasideListHead);
 206             Prcb->PPLookasideList[LookasideSmallIrpList].P = CurrentList;
 207             CurrentList++;
 208
 209         }
 210         else
 211         {
 212             Prcb->PPLookasideList[LookasideSmallIrpList].P = &IoSmallIrpLookaside;
 213         }
 214
 215         /* Set the MDL Completion List */
 216         Prcb->PPLookasideList[LookasideMdlList].L = &IopMdlLookasideList;
 217         if (CurrentList)
 218         {
 219             /* Initialize the Lookaside List for MDLs */
 220             ExInitializeSystemLookasideList(CurrentList,
 221                                             NonPagedPool,
 222                                             SmallIrpSize,
 223                                             TAG_MDL,
 224                                             128,
 225                                             &ExSystemLookasideListHead);
 226
 227             Prcb->PPLookasideList[LookasideMdlList].P = CurrentList;
 228             CurrentList++;
 229
 230         }
 231         else
 232         {
 233             Prcb->PPLookasideList[LookasideMdlList].P = &IopMdlLookasideList;
 234         }
 235     }
 236 }
 237
 238 BOOLEAN
 239 INIT_FUNCTION
 240 NTAPI
 241 IopCreateObjectTypes(VOID)
 242 {
 243     OBJECT_TYPE_INITIALIZER ObjectTypeInitializer;
 244     UNICODE_STRING Name;
 245
 246     /* Initialize default settings */
 247     RtlZeroMemory(&ObjectTypeInitializer, sizeof(ObjectTypeInitializer));
 248     ObjectTypeInitializer.Length = sizeof(ObjectTypeInitializer);
 249     ObjectTypeInitializer.PoolType = NonPagedPool;
 250     ObjectTypeInitializer.InvalidAttributes = OBJ_OPENLINK;
 251     ObjectTypeInitializer.ValidAccessMask = FILE_ALL_ACCESS;
 252     ObjectTypeInitializer.UseDefaultObject = TRUE;
 253     ObjectTypeInitializer.GenericMapping = IopFileMapping;
 254
 255     /* Do the Adapter Type */
 256     RtlInitUnicodeString(&Name, L"Adapter");
 257     if (!NT_SUCCESS(ObCreateObjectType(&Name,
 258                                        &ObjectTypeInitializer,
 259                                        NULL,
 260                                        &IoAdapterObjectType))) return FALSE;
 261
 262     /* Do the Controller Type */
 263     RtlInitUnicodeString(&Name, L"Controller");
 264     ObjectTypeInitializer.DefaultNonPagedPoolCharge = sizeof(CONTROLLER_OBJECT);
 265     if (!NT_SUCCESS(ObCreateObjectType(&Name,
 266                                        &ObjectTypeInitializer,
 267                                        NULL,
 268                                        &IoControllerObjectType))) return FALSE;
 269
 270     /* Do the Device Type */
 271     RtlInitUnicodeString(&Name, L"Device");
 272     ObjectTypeInitializer.DefaultNonPagedPoolCharge = sizeof(DEVICE_OBJECT);
 273     ObjectTypeInitializer.DeleteProcedure = IopDeleteDevice;
 274     ObjectTypeInitializer.ParseProcedure = IopParseDevice;
 275     ObjectTypeInitializer.SecurityProcedure = IopSecurityFile;
 276     if (!NT_SUCCESS(ObCreateObjectType(&Name,
 277                                        &ObjectTypeInitializer,
 278                                        NULL,
 279                                        &IoDeviceObjectType))) return FALSE;
 280
 281     /* Initialize the Driver object type */
 282     RtlInitUnicodeString(&Name, L"Driver");
 283     ObjectTypeInitializer.DefaultNonPagedPoolCharge = sizeof(DRIVER_OBJECT);
 284     ObjectTypeInitializer.DeleteProcedure = IopDeleteDriver;
 285     ObjectTypeInitializer.ParseProcedure = NULL;
 286     ObjectTypeInitializer.SecurityProcedure = NULL;
 287     if (!NT_SUCCESS(ObCreateObjectType(&Name,
 288                                        &ObjectTypeInitializer,
 289                                        NULL,
 290                                        &IoDriverObjectType))) return FALSE;
 291
 292     /* Initialize the I/O Completion object type */
 293     RtlInitUnicodeString(&Name, L"IoCompletion");
 294     ObjectTypeInitializer.DefaultNonPagedPoolCharge = sizeof(KQUEUE);
 295     ObjectTypeInitializer.ValidAccessMask = IO_COMPLETION_ALL_ACCESS;
 296     ObjectTypeInitializer.InvalidAttributes |= OBJ_PERMANENT;
 297     ObjectTypeInitializer.GenericMapping = IopCompletionMapping;
 298     ObjectTypeInitializer.DeleteProcedure = IopDeleteIoCompletion;
 299     if (!NT_SUCCESS(ObCreateObjectType(&Name,
 300                                        &ObjectTypeInitializer,
 301                                        NULL,
 302                                        &IoCompletionType))) return FALSE;
 303
 304     /* Initialize the File object type  */
 305     RtlInitUnicodeString(&Name, L"File");
 306     ObjectTypeInitializer.DefaultNonPagedPoolCharge = sizeof(FILE_OBJECT);
 307     ObjectTypeInitializer.InvalidAttributes |= OBJ_EXCLUSIVE;
 308     ObjectTypeInitializer.MaintainHandleCount = TRUE;
 309     ObjectTypeInitializer.ValidAccessMask = FILE_ALL_ACCESS;
 310     ObjectTypeInitializer.GenericMapping = IopFileMapping;
 311     ObjectTypeInitializer.CloseProcedure = IopCloseFile;
 312     ObjectTypeInitializer.DeleteProcedure = IopDeleteFile;
 313     ObjectTypeInitializer.SecurityProcedure = IopSecurityFile;
 314     ObjectTypeInitializer.QueryNameProcedure = IopQueryNameFile;
 315     ObjectTypeInitializer.ParseProcedure = IopParseFile;
 316     ObjectTypeInitializer.UseDefaultObject = FALSE;
 317     if (!NT_SUCCESS(ObCreateObjectType(&Name,
 318                                        &ObjectTypeInitializer,
 319                                        NULL,
 320                                        &IoFileObjectType))) return FALSE;
 321
 322     /* Success */
 323     return TRUE;
 324 }
 325
 326 BOOLEAN
 327 INIT_FUNCTION
 328 NTAPI
 329 IopCreateRootDirectories()
 330 {
 331     OBJECT_ATTRIBUTES ObjectAttributes;
 332     UNICODE_STRING DirName;
 333     HANDLE Handle;
 334
 335     /* Create the '\Driver' object directory */
 336     RtlInitUnicodeString(&DirName, L"\\Driver");
 337     InitializeObjectAttributes(&ObjectAttributes,
 338                                &DirName,
 339                                OBJ_PERMANENT,
 340                                NULL,
 341                                NULL);
 342     if (!NT_SUCCESS(NtCreateDirectoryObject(&Handle,
 343                                             DIRECTORY_ALL_ACCESS,
 344                                             &ObjectAttributes))) return FALSE;
 345     NtClose(Handle);
 346
 347     /* Create the '\FileSystem' object directory */
 348     RtlInitUnicodeString(&DirName, L"\\FileSystem");
 349     InitializeObjectAttributes(&ObjectAttributes,
 350                                &DirName,
 351                                OBJ_PERMANENT,
 352                                NULL,
 353                                NULL);
 354     if (!NT_SUCCESS(NtCreateDirectoryObject(&Handle,
 355                                             DIRECTORY_ALL_ACCESS,
 356                                             &ObjectAttributes))) return FALSE;
 357     NtClose(Handle);
 358
 359     /* Return success */
 360     return TRUE;
 361 }
 362
 363 BOOLEAN
 364 INIT_FUNCTION
 365 NTAPI
 366 IopMarkBootPartition(IN PLOADER_PARAMETER_BLOCK LoaderBlock)
 367 {
 368     OBJECT_ATTRIBUTES ObjectAttributes;
 369     STRING DeviceString;
 370     CHAR Buffer[256];
 371     UNICODE_STRING DeviceName;
 372     NTSTATUS Status;
 373     HANDLE FileHandle;
 374     IO_STATUS_BLOCK IoStatusBlock;
 375     PFILE_OBJECT FileObject;
 376
 377     /* Build the ARC device name */
 378     sprintf(Buffer, "\\ArcName\\%s", LoaderBlock->ArcBootDeviceName);
 379     RtlInitAnsiString(&DeviceString, Buffer);
 380     Status = RtlAnsiStringToUnicodeString(&DeviceName, &DeviceString, TRUE);
 381     if (!NT_SUCCESS(Status)) return FALSE;
 382
 383     /* Open it */
 384     InitializeObjectAttributes(&ObjectAttributes,
 385                                &DeviceName,
 386                                OBJ_CASE_INSENSITIVE,
 387                                NULL,
 388                                NULL);
 389     Status = ZwOpenFile(&FileHandle,
 390                         FILE_READ_ATTRIBUTES,
 391                         &ObjectAttributes,
 392                         &IoStatusBlock,
 393                         0,
 394                         FILE_NON_DIRECTORY_FILE);
 395     if (!NT_SUCCESS(Status))
 396     {
 397         /* Fail */
 398         KeBugCheckEx(INACCESSIBLE_BOOT_DEVICE,
 399                      (ULONG_PTR)&DeviceName,
 400                      Status,
 401                      0,
 402                      0);
 403     }
 404
 405     /* Get the DO */
 406     Status = ObReferenceObjectByHandle(FileHandle,
 407                                        0,
 408                                        IoFileObjectType,
 409                                        KernelMode,
 410                                        (PVOID *)&FileObject,
 411                                        NULL);
 412     if (!NT_SUCCESS(Status))
 413     {
 414         /* Fail */
 415         RtlFreeUnicodeString(&DeviceName);
 416         return FALSE;
 417     }
 418
 419     /* Mark it as the boot partition */
 420     FileObject->DeviceObject->Flags |= DO_SYSTEM_BOOT_PARTITION;
 421
 422     /* Save a copy of the DO for the I/O Error Logger */
 423     ObReferenceObject(FileObject->DeviceObject);
 424     IopErrorLogObject = FileObject->DeviceObject;
 425
 426     /* Cleanup and return success */
 427     RtlFreeUnicodeString(&DeviceName);
 428     NtClose(FileHandle);
 429     ObDereferenceObject(FileObject);
 430     return TRUE;
 431 }
 432
 433 BOOLEAN
 434 INIT_FUNCTION
 435 NTAPI
 436 IoInitSystem(IN PLOADER_PARAMETER_BLOCK LoaderBlock)
 437 {
 438     LARGE_INTEGER ExpireTime;
 439     NTSTATUS Status;
 440     CHAR Buffer[256];
 441     ANSI_STRING NtBootPath, RootString;
 442
 443     /* Initialize empty NT Boot Path */
 444     RtlInitEmptyAnsiString(&NtBootPath, Buffer, sizeof(Buffer));
 445
 446     /* Initialize the lookaside lists */
 447     IopInitLookasideLists();
 448
 449     /* Initialize all locks and lists */
 450     ExInitializeResource(&IopDatabaseResource);
 451     ExInitializeResource(&IopSecurityResource);
 452     KeInitializeGuardedMutex(&PnpNotifyListLock);
 453     InitializeListHead(&IopDiskFileSystemQueueHead);
 454     InitializeListHead(&IopCdRomFileSystemQueueHead);
 455     InitializeListHead(&IopTapeFileSystemQueueHead);
 456     InitializeListHead(&IopNetworkFileSystemQueueHead);
 457     InitializeListHead(&DriverBootReinitListHead);
 458     InitializeListHead(&DriverReinitListHead);
 459     InitializeListHead(&PnpNotifyListHead);
 460     InitializeListHead(&ShutdownListHead);
 461     InitializeListHead(&LastChanceShutdownListHead);
 462     InitializeListHead(&IopFsNotifyChangeQueueHead);
 463     InitializeListHead(&IopErrorLogListHead);
 464     KeInitializeSpinLock(&IoStatisticsLock);
 465     KeInitializeSpinLock(&DriverReinitListLock);
 466     KeInitializeSpinLock(&DriverBootReinitListLock);
 467     KeInitializeSpinLock(&ShutdownListLock);
 468     KeInitializeSpinLock(&IopLogListLock);
 469
 470     /* Initialize Timer List Lock */
 471     KeInitializeSpinLock(&IopTimerLock);
 472
 473     /* Initialize Timer List */
 474     InitializeListHead(&IopTimerQueueHead);
 475
 476     /* Initialize the DPC/Timer which will call the other Timer Routines */
 477     ExpireTime.QuadPart = -10000000;
 478     KeInitializeDpc(&IopTimerDpc, IopTimerDispatch, NULL);
 479     KeInitializeTimerEx(&IopTimer, SynchronizationTimer);
 480     KeSetTimerEx(&IopTimer, ExpireTime, 1000, &IopTimerDpc);
 481
 482     /* Create Object Types */
 483     if (!IopCreateObjectTypes())
 484     {
 485         DPRINT1("IopCreateObjectTypes failed!\n");
 486         return FALSE;
 487     }
 488
 489     /* Create Object Directories */
 490     if (!IopCreateRootDirectories())
 491     {
 492         DPRINT1("IopCreateRootDirectories failed!\n");
 493         return FALSE;
 494     }
 495
 496     /* Initialize PnP manager */
 497     IopInitializePlugPlayServices();
 498
 499     /* Initialize HAL Root Bus Driver */
 500     HalInitPnpDriver();
 501
 502     /* Make loader block available for the whole kernel */
 503     IopLoaderBlock = LoaderBlock;
 504
 505     /* Load boot start drivers */
 506     IopInitializeBootDrivers();
 507
 508     /* Call back drivers that asked for */
 509     IopReinitializeBootDrivers();
 510
 511     /* Check if this was a ramdisk boot */
 512     if (!_strnicmp(LoaderBlock->ArcBootDeviceName, "ramdisk(0)", 10))
 513     {
 514         /* Initialize the ramdisk driver */
 515         IopStartRamdisk(LoaderBlock);
 516     }
 517
 518     /* No one should need loader block any longer */
 519     IopLoaderBlock = NULL;
 520
 521     /* Create ARC names for boot devices */
 522     Status = IopCreateArcNames(LoaderBlock);
 523     if (!NT_SUCCESS(Status))
 524     {
 525         DPRINT1("IopCreateArcNames failed: %lx\n", Status);
 526         return FALSE;
 527     }
 528
 529     /* Mark the system boot partition */
 530     if (!IopMarkBootPartition(LoaderBlock))
 531     {
 532         DPRINT1("IopMarkBootPartition failed!\n");
 533         return FALSE;
 534     }
 535
 536     /* Initialize PnP root relations */
 537     IopEnumerateDevice(IopRootDeviceNode->PhysicalDeviceObject);
 538
 539 #ifndef _WINKD_
 540     /* Read KDB Data */
 541     KdbInit();
 542
 543     /* I/O is now setup for disk access, so phase 3 */
 544     KdInitSystem(3, LoaderBlock);
 545 #endif
 546
 547     /* Load services for devices found by PnP manager */
 548     IopInitializePnpServices(IopRootDeviceNode);
 549
 550     /* Load system start drivers */
 551     IopInitializeSystemDrivers();
 552     PnpSystemInit = TRUE;
 553
 554     /* Reinitialize drivers that requested it */
 555     IopReinitializeDrivers();
 556
 557     /* Convert SystemRoot from ARC to NT path */
 558     Status = IopReassignSystemRoot(LoaderBlock, &NtBootPath);
 559     if (!NT_SUCCESS(Status))
 560     {
 561         DPRINT1("IopReassignSystemRoot failed: %lx\n", Status);
 562         return FALSE;
 563     }
 564
 565     /* Set the ANSI_STRING for the root path */
 566     RootString.MaximumLength = NtSystemRoot.MaximumLength / sizeof(WCHAR);
 567     RootString.Length = 0;
 568     RootString.Buffer = ExAllocatePoolWithTag(PagedPool,
 569                                               RootString.MaximumLength,
 570                                               TAG_IO);
 571
 572     /* Convert the path into the ANSI_STRING */
 573     Status = RtlUnicodeStringToAnsiString(&RootString, &NtSystemRoot, FALSE);
 574     if (!NT_SUCCESS(Status))
 575     {
 576         DPRINT1("RtlUnicodeStringToAnsiString failed: %lx\n", Status);
 577         return FALSE;
 578     }
 579
 580     /* Assign drive letters */
 581     IoAssignDriveLetters(LoaderBlock,
 582                          &NtBootPath,
 583                          (PUCHAR)RootString.Buffer,
 584                          &RootString);
 585
 586     /* Update system root */
 587     Status = RtlAnsiStringToUnicodeString(&NtSystemRoot, &RootString, FALSE);
 588     if (!NT_SUCCESS(Status))
 589     {
 590         DPRINT1("RtlAnsiStringToUnicodeString failed: %lx\n", Status);
 591         return FALSE;
 592     }
 593
 594     /* Load the System DLL and its Entrypoints */
 595     Status = PsLocateSystemDll();
 596     if (!NT_SUCCESS(Status))
 597     {
 598         DPRINT1("PsLocateSystemDll failed: %lx\n", Status);
 599         return FALSE;
 600     }
 601
 602     /* Return success */
 603     return TRUE;
 604 }
 605
 606 /* EOF */