pnpres.c

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/*
 * PROJECT:         ReactOS Kernel
 * COPYRIGHT:       GPL - See COPYING in the top level directory
 * FILE:            ntoskrnl/io/pnpmgr/pnpres.c
 * PURPOSE:         Resource handling code
 * PROGRAMMERS:     Cameron Gutman (cameron.gutman@reactos.org)
 *                  ReactOS Portable Systems Group
 */

#include <ntoskrnl.h>

#define NDEBUG
#include <debug.h>

static
BOOLEAN
IopCheckDescriptorForConflict(PCM_PARTIAL_RESOURCE_DESCRIPTOR CmDesc, OPTIONAL PCM_PARTIAL_RESOURCE_DESCRIPTOR ConflictingDescriptor)
{
   CM_RESOURCE_LIST CmList;
   NTSTATUS Status;

   CmList.Count = 1;
   CmList.List[0].InterfaceType = InterfaceTypeUndefined;
   CmList.List[0].BusNumber = 0;
   CmList.List[0].PartialResourceList.Version = 1;
   CmList.List[0].PartialResourceList.Revision = 1;
   CmList.List[0].PartialResourceList.Count = 1;
   CmList.List[0].PartialResourceList.PartialDescriptors[0] = *CmDesc;

   Status = IopDetectResourceConflict(&CmList, TRUE, ConflictingDescriptor);
   if (Status == STATUS_CONFLICTING_ADDRESSES)
       return TRUE;

   return FALSE;
}

static
BOOLEAN
IopFindBusNumberResource(
   IN PIO_RESOURCE_DESCRIPTOR IoDesc,
   OUT PCM_PARTIAL_RESOURCE_DESCRIPTOR CmDesc)
{
   ULONG Start;
   CM_PARTIAL_RESOURCE_DESCRIPTOR ConflictingDesc;

   ASSERT(IoDesc->Type == CmDesc->Type);
   ASSERT(IoDesc->Type == CmResourceTypeBusNumber);

   for (Start = IoDesc->u.BusNumber.MinBusNumber;
        Start <= IoDesc->u.BusNumber.MaxBusNumber - IoDesc->u.BusNumber.Length + 1;
        Start++)
   {
        CmDesc->u.BusNumber.Length = IoDesc->u.BusNumber.Length;
        CmDesc->u.BusNumber.Start = Start;

        if (IopCheckDescriptorForConflict(CmDesc, &ConflictingDesc))
        {
            Start += ConflictingDesc.u.BusNumber.Start + ConflictingDesc.u.BusNumber.Length;
        }
        else
        {
            DPRINT1("Satisfying bus number requirement with 0x%x (length: 0x%x)\n", Start, CmDesc->u.BusNumber.Length);
            return TRUE;
        }
   }

   return FALSE;
}

static
BOOLEAN
IopFindMemoryResource(
   IN PIO_RESOURCE_DESCRIPTOR IoDesc,
   OUT PCM_PARTIAL_RESOURCE_DESCRIPTOR CmDesc)
{
   ULONGLONG Start;
   CM_PARTIAL_RESOURCE_DESCRIPTOR ConflictingDesc;

   ASSERT(IoDesc->Type == CmDesc->Type);
   ASSERT(IoDesc->Type == CmResourceTypeMemory);

   /* HACK */
   if (IoDesc->u.Memory.Alignment == 0) IoDesc->u.Memory.Alignment = 1;

   for (Start = (ULONGLONG)IoDesc->u.Memory.MinimumAddress.QuadPart;
        Start <= (ULONGLONG)IoDesc->u.Memory.MaximumAddress.QuadPart - IoDesc->u.Memory.Length + 1;
        Start += IoDesc->u.Memory.Alignment)
   {
        CmDesc->u.Memory.Length = IoDesc->u.Memory.Length;
        CmDesc->u.Memory.Start.QuadPart = (LONGLONG)Start;

        if (IopCheckDescriptorForConflict(CmDesc, &ConflictingDesc))
        {
            Start += (ULONGLONG)ConflictingDesc.u.Memory.Start.QuadPart +
                     ConflictingDesc.u.Memory.Length;
        }
        else
        {
            DPRINT1("Satisfying memory requirement with 0x%I64x (length: 0x%x)\n", Start, CmDesc->u.Memory.Length);
            return TRUE;
        }
   }

   return FALSE;
}

static
BOOLEAN
IopFindPortResource(
   IN PIO_RESOURCE_DESCRIPTOR IoDesc,
   OUT PCM_PARTIAL_RESOURCE_DESCRIPTOR CmDesc)
{
   ULONGLONG Start;
   CM_PARTIAL_RESOURCE_DESCRIPTOR ConflictingDesc;

   ASSERT(IoDesc->Type == CmDesc->Type);
   ASSERT(IoDesc->Type == CmResourceTypePort);

   /* HACK */
   if (IoDesc->u.Port.Alignment == 0) IoDesc->u.Port.Alignment = 1;

   for (Start = (ULONGLONG)IoDesc->u.Port.MinimumAddress.QuadPart;
       Start <= (ULONGLONG)IoDesc->u.Port.MaximumAddress.QuadPart - IoDesc->u.Port.Length + 1;
        Start += IoDesc->u.Port.Alignment)
   {
        CmDesc->u.Port.Length = IoDesc->u.Port.Length;
        CmDesc->u.Port.Start.QuadPart = (LONGLONG)Start;

        if (IopCheckDescriptorForConflict(CmDesc, &ConflictingDesc))
        {
            Start += (ULONGLONG)ConflictingDesc.u.Port.Start.QuadPart + ConflictingDesc.u.Port.Length;
        }
        else
        {
            DPRINT("Satisfying port requirement with 0x%I64x (length: 0x%x)\n", Start, CmDesc->u.Port.Length);
            return TRUE;
        }
   }

   DPRINT1("IopFindPortResource failed!\n");
   return FALSE;
}

static
BOOLEAN
IopFindDmaResource(
   IN PIO_RESOURCE_DESCRIPTOR IoDesc,
   OUT PCM_PARTIAL_RESOURCE_DESCRIPTOR CmDesc)
{
   ULONG Channel;

   ASSERT(IoDesc->Type == CmDesc->Type);
   ASSERT(IoDesc->Type == CmResourceTypeDma);

   for (Channel = IoDesc->u.Dma.MinimumChannel;
        Channel <= IoDesc->u.Dma.MaximumChannel;
        Channel++)
   {
        CmDesc->u.Dma.Channel = Channel;
        CmDesc->u.Dma.Port = 0;

        if (!IopCheckDescriptorForConflict(CmDesc, NULL))
        {
            DPRINT1("Satisfying DMA requirement with channel 0x%x\n", Channel);
            return TRUE;
        }
   }

   return FALSE;
}

static
BOOLEAN
IopFindInterruptResource(
   IN PIO_RESOURCE_DESCRIPTOR IoDesc,
   OUT PCM_PARTIAL_RESOURCE_DESCRIPTOR CmDesc)
{
   ULONG Vector;

   ASSERT(IoDesc->Type == CmDesc->Type);
   ASSERT(IoDesc->Type == CmResourceTypeInterrupt);

   for (Vector = IoDesc->u.Interrupt.MinimumVector;
        Vector <= IoDesc->u.Interrupt.MaximumVector;
        Vector++)
   {
        CmDesc->u.Interrupt.Vector = Vector;
        CmDesc->u.Interrupt.Level = Vector;
        CmDesc->u.Interrupt.Affinity = (KAFFINITY)-1;

        if (!IopCheckDescriptorForConflict(CmDesc, NULL))
        {
            DPRINT1("Satisfying interrupt requirement with IRQ 0x%x\n", Vector);
            return TRUE;
        }
   }

   return FALSE;
}

NTSTATUS NTAPI
IopFixupResourceListWithRequirements(
   IN PIO_RESOURCE_REQUIREMENTS_LIST RequirementsList,
   OUT PCM_RESOURCE_LIST *ResourceList)
{
    ULONG i, OldCount;
    BOOLEAN AlternateRequired = FALSE;

    /* Save the initial resource count when we got here so we can restore if an alternate fails */
    if (*ResourceList != NULL)
        OldCount = (*ResourceList)->List[0].PartialResourceList.Count;
    else
        OldCount = 0;

    for (i = 0; i < RequirementsList->AlternativeLists; i++)
    {
        ULONG ii;
        PIO_RESOURCE_LIST ResList = &RequirementsList->List[i];

        /* We need to get back to where we were before processing the last alternative list */
        if (OldCount == 0 && *ResourceList != NULL)
        {
            /* Just free it and kill the pointer */
            ExFreePool(*ResourceList);
            *ResourceList = NULL;
        }
        else if (OldCount != 0)
        {
            PCM_RESOURCE_LIST NewList;

            /* Let's resize it */
            (*ResourceList)->List[0].PartialResourceList.Count = OldCount;

            /* Allocate the new smaller list */
            NewList = ExAllocatePool(PagedPool, PnpDetermineResourceListSize(*ResourceList));
            if (!NewList)
                return STATUS_NO_MEMORY;

            /* Copy the old stuff back */
            RtlCopyMemory(NewList, *ResourceList, PnpDetermineResourceListSize(*ResourceList));

            /* Free the old one */
            ExFreePool(*ResourceList);

            /* Store the pointer to the new one */
            *ResourceList = NewList;
        }

        for (ii = 0; ii < ResList->Count; ii++)
        {
            ULONG iii;
            PCM_PARTIAL_RESOURCE_LIST PartialList = (*ResourceList) ? &(*ResourceList)->List[0].PartialResourceList : NULL;
            PIO_RESOURCE_DESCRIPTOR IoDesc = &ResList->Descriptors[ii];
            BOOLEAN Matched = FALSE;

            /* Skip alternates if we don't need one */
            if (!AlternateRequired && (IoDesc->Option & IO_RESOURCE_ALTERNATIVE))
            {
                DPRINT("Skipping unneeded alternate\n");
                continue;
            }

            /* Check if we couldn't satsify a requirement or its alternates */
            if (AlternateRequired && !(IoDesc->Option & IO_RESOURCE_ALTERNATIVE))
            {
                DPRINT1("Unable to satisfy preferred resource or alternates in list %lu\n", i);

                /* Break out of this loop and try the next list */
                break;
            }

            for (iii = 0; PartialList && iii < PartialList->Count && !Matched; iii++)
            {
                PCM_PARTIAL_RESOURCE_DESCRIPTOR CmDesc = &PartialList->PartialDescriptors[iii];

                /* First check types */
                if (IoDesc->Type != CmDesc->Type)
                    continue;

                switch (IoDesc->Type)
                {
                    case CmResourceTypeInterrupt:
                        /* Make sure it satisfies our vector range */
                        if (CmDesc->u.Interrupt.Vector >= IoDesc->u.Interrupt.MinimumVector &&
                            CmDesc->u.Interrupt.Vector <= IoDesc->u.Interrupt.MaximumVector)
                        {
                            /* Found it */
                            Matched = TRUE;
                        }
                        else
                        {
                            DPRINT("Interrupt - Not a match! 0x%x not inside 0x%x to 0x%x\n",
                                   CmDesc->u.Interrupt.Vector,
                                   IoDesc->u.Interrupt.MinimumVector,
                                   IoDesc->u.Interrupt.MaximumVector);
                        }
                        break;

                    case CmResourceTypeMemory:
                    case CmResourceTypePort:
                        /* Make sure the length matches and it satisfies our address range */
                        if (CmDesc->u.Memory.Length == IoDesc->u.Memory.Length &&
                            (ULONGLONG)CmDesc->u.Memory.Start.QuadPart >= (ULONGLONG)IoDesc->u.Memory.MinimumAddress.QuadPart &&
                            (ULONGLONG)CmDesc->u.Memory.Start.QuadPart + CmDesc->u.Memory.Length - 1 <= (ULONGLONG)IoDesc->u.Memory.MaximumAddress.QuadPart)
                        {
                            /* Found it */
                            Matched = TRUE;
                        }
                        else
                        {
                            DPRINT("Memory/Port - Not a match! 0x%I64x with length 0x%x not inside 0x%I64x to 0x%I64x with length 0x%x\n",
                                   CmDesc->u.Memory.Start.QuadPart,
                                   CmDesc->u.Memory.Length,
                                   IoDesc->u.Memory.MinimumAddress.QuadPart,
                                   IoDesc->u.Memory.MaximumAddress.QuadPart,
                                   IoDesc->u.Memory.Length);
                        }
                        break;

                    case CmResourceTypeBusNumber:
                        /* Make sure the length matches and it satisfies our bus number range */
                        if (CmDesc->u.BusNumber.Length == IoDesc->u.BusNumber.Length &&
                            CmDesc->u.BusNumber.Start >= IoDesc->u.BusNumber.MinBusNumber &&
                            CmDesc->u.BusNumber.Start + CmDesc->u.BusNumber.Length - 1 <= IoDesc->u.BusNumber.MaxBusNumber)
                        {
                            /* Found it */
                            Matched = TRUE;
                        }
                        else
                        {
                            DPRINT("Bus Number - Not a match! 0x%x with length 0x%x not inside 0x%x to 0x%x with length 0x%x\n",
                                   CmDesc->u.BusNumber.Start,
                                   CmDesc->u.BusNumber.Length,
                                   IoDesc->u.BusNumber.MinBusNumber,
                                   IoDesc->u.BusNumber.MaxBusNumber,
                                   IoDesc->u.BusNumber.Length);
                        }
                        break;

                    case CmResourceTypeDma:
                        /* Make sure it fits in our channel range */
                        if (CmDesc->u.Dma.Channel >= IoDesc->u.Dma.MinimumChannel &&
                            CmDesc->u.Dma.Channel <= IoDesc->u.Dma.MaximumChannel)
                        {
                            /* Found it */
                            Matched = TRUE;
                        }
                        else
                        {
                            DPRINT("DMA - Not a match! 0x%x not inside 0x%x to 0x%x\n",
                                   CmDesc->u.Dma.Channel,
                                   IoDesc->u.Dma.MinimumChannel,
                                   IoDesc->u.Dma.MaximumChannel);
                        }
                        break;

                    default:
                        /* Other stuff is fine */
                        Matched = TRUE;
                        break;
                }
            }

            /* Check if we found a matching descriptor */
            if (!Matched)
            {
                PCM_RESOURCE_LIST NewList;
                CM_PARTIAL_RESOURCE_DESCRIPTOR NewDesc;
                PCM_PARTIAL_RESOURCE_DESCRIPTOR DescPtr;
                BOOLEAN FoundResource = TRUE;

                /* Setup the new CM descriptor */
                NewDesc.Type = IoDesc->Type;
                NewDesc.Flags = IoDesc->Flags;
                NewDesc.ShareDisposition = IoDesc->ShareDisposition;

                /* Let'se see if we can find a resource to satisfy this */
                switch (IoDesc->Type)
                {
                    case CmResourceTypeInterrupt:
                        /* Find an available interrupt */
                        if (!IopFindInterruptResource(IoDesc, &NewDesc))
                        {
                            DPRINT1("Failed to find an available interrupt resource (0x%x to 0x%x)\n",
                                    IoDesc->u.Interrupt.MinimumVector, IoDesc->u.Interrupt.MaximumVector);

                            FoundResource = FALSE;
                        }
                        break;

                    case CmResourceTypePort:
                        /* Find an available port range */
                        if (!IopFindPortResource(IoDesc, &NewDesc))
                        {
                            DPRINT1("Failed to find an available port resource (0x%I64x to 0x%I64x length: 0x%x)\n",
                                    IoDesc->u.Port.MinimumAddress.QuadPart, IoDesc->u.Port.MaximumAddress.QuadPart,
                                    IoDesc->u.Port.Length);

                            FoundResource = FALSE;
                        }
                        break;

                    case CmResourceTypeMemory:
                        /* Find an available memory range */
                        if (!IopFindMemoryResource(IoDesc, &NewDesc))
                        {
                            DPRINT1("Failed to find an available memory resource (0x%I64x to 0x%I64x length: 0x%x)\n",
                                    IoDesc->u.Memory.MinimumAddress.QuadPart, IoDesc->u.Memory.MaximumAddress.QuadPart,
                                    IoDesc->u.Memory.Length);

                            FoundResource = FALSE;
                        }
                        break;

                    case CmResourceTypeBusNumber:
                        /* Find an available bus address range */
                        if (!IopFindBusNumberResource(IoDesc, &NewDesc))
                        {
                            DPRINT1("Failed to find an available bus number resource (0x%x to 0x%x length: 0x%x)\n",
                                    IoDesc->u.BusNumber.MinBusNumber, IoDesc->u.BusNumber.MaxBusNumber,
                                    IoDesc->u.BusNumber.Length);

                            FoundResource = FALSE;
                        }
                        break;

                    case CmResourceTypeDma:
                        /* Find an available DMA channel */
                        if (!IopFindDmaResource(IoDesc, &NewDesc))
                        {
                            DPRINT1("Failed to find an available dma resource (0x%x to 0x%x)\n",
                                    IoDesc->u.Dma.MinimumChannel, IoDesc->u.Dma.MaximumChannel);

                            FoundResource = FALSE;
                        }
                        break;

                    default:
                        DPRINT1("Unsupported resource type: %x\n", IoDesc->Type);
                        FoundResource = FALSE;
                        break;
                }

                /* Check if it's missing and required */
                if (!FoundResource && IoDesc->Option == 0)
                {
                    /* Break out of this loop and try the next list */
                    DPRINT1("Unable to satisfy required resource in list %lu\n", i);
                    break;
                }
                else if (!FoundResource)
                {
                    /* Try an alternate for this preferred descriptor */
                    AlternateRequired = TRUE;
                    continue;
                }
                else
                {
                    /* Move on to the next preferred or required descriptor after this one */
                    AlternateRequired = FALSE;
                }

                /* Figure out what we need */
                if (PartialList == NULL)
                {
                    /* We need a new list */
                    NewList = ExAllocatePool(PagedPool, sizeof(CM_RESOURCE_LIST));
                    if (!NewList)
                        return STATUS_NO_MEMORY;

                    /* Set it up */
                    NewList->Count = 1;
                    NewList->List[0].InterfaceType = RequirementsList->InterfaceType;
                    NewList->List[0].BusNumber = RequirementsList->BusNumber;
                    NewList->List[0].PartialResourceList.Version = 1;
                    NewList->List[0].PartialResourceList.Revision = 1;
                    NewList->List[0].PartialResourceList.Count = 1;

                    /* Set our pointer */
                    DescPtr = &NewList->List[0].PartialResourceList.PartialDescriptors[0];
                }
                else
                {
                    /* Allocate the new larger list */
                    NewList = ExAllocatePool(PagedPool, PnpDetermineResourceListSize(*ResourceList) + sizeof(CM_PARTIAL_RESOURCE_DESCRIPTOR));
                    if (!NewList)
                        return STATUS_NO_MEMORY;

                    /* Copy the old stuff back */
                    RtlCopyMemory(NewList, *ResourceList, PnpDetermineResourceListSize(*ResourceList));

                    /* Set our pointer */
                    DescPtr = &NewList->List[0].PartialResourceList.PartialDescriptors[NewList->List[0].PartialResourceList.Count];

                    /* Increment the descriptor count */
                    NewList->List[0].PartialResourceList.Count++;

                    /* Free the old list */
                    ExFreePool(*ResourceList);
                }

                /* Copy the descriptor in */
                *DescPtr = NewDesc;

                /* Store the new list */
                *ResourceList = NewList;
            }
        }

        /* Check if we need an alternate with no resources left */
        if (AlternateRequired)
        {
            DPRINT1("Unable to satisfy preferred resource or alternates in list %lu\n", i);

            /* Try the next alternate list */
            continue;
        }

        /* We're done because we satisfied one of the alternate lists */
        return STATUS_SUCCESS;
    }

    /* We ran out of alternates */
    DPRINT1("Out of alternate lists!\n");

    /* Free the list */
    if (*ResourceList)
    {
        ExFreePool(*ResourceList);
        *ResourceList = NULL;
    }

    /* Fail */
    return STATUS_CONFLICTING_ADDRESSES;
}

static
BOOLEAN
IopCheckResourceDescriptor(
   IN PCM_PARTIAL_RESOURCE_DESCRIPTOR ResDesc,
   IN PCM_RESOURCE_LIST ResourceList,
   IN BOOLEAN Silent,
   OUT OPTIONAL PCM_PARTIAL_RESOURCE_DESCRIPTOR ConflictingDescriptor)
{
   ULONG i, ii;
   BOOLEAN Result = FALSE;

   for (i = 0; i < ResourceList->Count; i++)
   {
      PCM_PARTIAL_RESOURCE_LIST ResList = &ResourceList->List[i].PartialResourceList;
      for (ii = 0; ii < ResList->Count; ii++)
      {
         PCM_PARTIAL_RESOURCE_DESCRIPTOR ResDesc2 = &ResList->PartialDescriptors[ii];

         /* We don't care about shared resources */
         if (ResDesc->ShareDisposition == CmResourceShareShared &&
             ResDesc2->ShareDisposition == CmResourceShareShared)
             continue;

         /* Make sure we're comparing the same types */
         if (ResDesc->Type != ResDesc2->Type)
             continue;

         switch (ResDesc->Type)
         {
             case CmResourceTypeMemory:
                 if (((ULONGLONG)ResDesc->u.Memory.Start.QuadPart < (ULONGLONG)ResDesc2->u.Memory.Start.QuadPart &&
                      (ULONGLONG)ResDesc->u.Memory.Start.QuadPart + ResDesc->u.Memory.Length >
                      (ULONGLONG)ResDesc2->u.Memory.Start.QuadPart) || ((ULONGLONG)ResDesc2->u.Memory.Start.QuadPart <
                      (ULONGLONG)ResDesc->u.Memory.Start.QuadPart && (ULONGLONG)ResDesc2->u.Memory.Start.QuadPart +
                      ResDesc2->u.Memory.Length > (ULONGLONG)ResDesc->u.Memory.Start.QuadPart))
                 {
                      if (!Silent)
                      {
                          DPRINT1("Resource conflict: Memory (0x%I64x to 0x%I64x vs. 0x%I64x to 0x%I64x)\n",
                                  ResDesc->u.Memory.Start.QuadPart, ResDesc->u.Memory.Start.QuadPart +
                                  ResDesc->u.Memory.Length, ResDesc2->u.Memory.Start.QuadPart,
                                  ResDesc2->u.Memory.Start.QuadPart + ResDesc2->u.Memory.Length);
                      }

                      Result = TRUE;

                      goto ByeBye;
                 }
                 break;

             case CmResourceTypePort:
                 if (((ULONGLONG)ResDesc->u.Port.Start.QuadPart < (ULONGLONG)ResDesc2->u.Port.Start.QuadPart &&
                      (ULONGLONG)ResDesc->u.Port.Start.QuadPart + ResDesc->u.Port.Length >
                      (ULONGLONG)ResDesc2->u.Port.Start.QuadPart) || ((ULONGLONG)ResDesc2->u.Port.Start.QuadPart <
                      (ULONGLONG)ResDesc->u.Port.Start.QuadPart && (ULONGLONG)ResDesc2->u.Port.Start.QuadPart +
                      ResDesc2->u.Port.Length > (ULONGLONG)ResDesc->u.Port.Start.QuadPart))
                 {
                      if (!Silent)
                      {
                          DPRINT1("Resource conflict: Port (0x%I64x to 0x%I64x vs. 0x%I64x to 0x%I64x)\n",
                                  ResDesc->u.Port.Start.QuadPart, ResDesc->u.Port.Start.QuadPart +
                                  ResDesc->u.Port.Length, ResDesc2->u.Port.Start.QuadPart,
                                  ResDesc2->u.Port.Start.QuadPart + ResDesc2->u.Port.Length);
                      }

                      Result = TRUE;

                      goto ByeBye;
                 }
                 break;

             case CmResourceTypeInterrupt:
                 if (ResDesc->u.Interrupt.Vector == ResDesc2->u.Interrupt.Vector)
                 {
                      if (!Silent)
                      {
                          DPRINT1("Resource conflict: IRQ (0x%x 0x%x vs. 0x%x 0x%x)\n",
                                  ResDesc->u.Interrupt.Vector, ResDesc->u.Interrupt.Level,
                                  ResDesc2->u.Interrupt.Vector, ResDesc2->u.Interrupt.Level);
                      }

                      Result = TRUE;

                      goto ByeBye;
                 }
                 break;

             case CmResourceTypeBusNumber:
                 if ((ResDesc->u.BusNumber.Start < ResDesc2->u.BusNumber.Start &&
                      ResDesc->u.BusNumber.Start + ResDesc->u.BusNumber.Length >
                      ResDesc2->u.BusNumber.Start) || (ResDesc2->u.BusNumber.Start <
                      ResDesc->u.BusNumber.Start && ResDesc2->u.BusNumber.Start +
                      ResDesc2->u.BusNumber.Length > ResDesc->u.BusNumber.Start))
                 {
                      if (!Silent)
                      {
                          DPRINT1("Resource conflict: Bus number (0x%x to 0x%x vs. 0x%x to 0x%x)\n",
                                  ResDesc->u.BusNumber.Start, ResDesc->u.BusNumber.Start +
                                  ResDesc->u.BusNumber.Length, ResDesc2->u.BusNumber.Start,
                                  ResDesc2->u.BusNumber.Start + ResDesc2->u.BusNumber.Length);
                      }

                      Result = TRUE;

                      goto ByeBye;
                 }
                 break;

             case CmResourceTypeDma:
                 if (ResDesc->u.Dma.Channel == ResDesc2->u.Dma.Channel)
                 {
                     if (!Silent)
                     {
                         DPRINT1("Resource conflict: Dma (0x%x 0x%x vs. 0x%x 0x%x)\n",
                                 ResDesc->u.Dma.Channel, ResDesc->u.Dma.Port,
                                 ResDesc2->u.Dma.Channel, ResDesc2->u.Dma.Port);
                     }

                     Result = TRUE;

                     goto ByeBye;
                 }
                 break;
         }
      }
   }

ByeBye:

   if (Result && ConflictingDescriptor)
   {
       RtlCopyMemory(ConflictingDescriptor,
                     ResDesc,
                     sizeof(CM_PARTIAL_RESOURCE_DESCRIPTOR));
   }

   return Result;
}

static
NTSTATUS
IopUpdateControlKeyWithResources(IN PDEVICE_NODE DeviceNode)
{
   UNICODE_STRING EnumRoot = RTL_CONSTANT_STRING(ENUM_ROOT);
   UNICODE_STRING Control = RTL_CONSTANT_STRING(L"Control");
   UNICODE_STRING ValueName = RTL_CONSTANT_STRING(L"AllocConfig");
   HANDLE EnumKey, InstanceKey, ControlKey;
   NTSTATUS Status;
   OBJECT_ATTRIBUTES ObjectAttributes;

   /* Open the Enum key */
   Status = IopOpenRegistryKeyEx(&EnumKey, NULL, &EnumRoot, KEY_ENUMERATE_SUB_KEYS);
   if (!NT_SUCCESS(Status))
       return Status;

   /* Open the instance key (eg. Root\PNP0A03) */
   Status = IopOpenRegistryKeyEx(&InstanceKey, EnumKey, &DeviceNode->InstancePath, KEY_ENUMERATE_SUB_KEYS);
   ZwClose(EnumKey);

   if (!NT_SUCCESS(Status))
       return Status;

   /* Create/Open the Control key */
   InitializeObjectAttributes(&ObjectAttributes,
                              &Control,
                              OBJ_CASE_INSENSITIVE | OBJ_KERNEL_HANDLE,
                              InstanceKey,
                              NULL);
   Status = ZwCreateKey(&ControlKey,
                        KEY_SET_VALUE,
                        &ObjectAttributes,
                        0,
                        NULL,
                        REG_OPTION_VOLATILE,
                        NULL);
   ZwClose(InstanceKey);

   if (!NT_SUCCESS(Status))
       return Status;

   /* Write the resource list */
   Status = ZwSetValueKey(ControlKey,
                          &ValueName,
                          0,
                          REG_RESOURCE_LIST,
                          DeviceNode->ResourceList,
                          PnpDetermineResourceListSize(DeviceNode->ResourceList));
   ZwClose(ControlKey);

   if (!NT_SUCCESS(Status))
       return Status;

   return STATUS_SUCCESS;
}

static
NTSTATUS
IopFilterResourceRequirements(IN PDEVICE_NODE DeviceNode)
{
   IO_STACK_LOCATION Stack;
   IO_STATUS_BLOCK IoStatusBlock;
   NTSTATUS Status;

   DPRINT("Sending IRP_MN_FILTER_RESOURCE_REQUIREMENTS to device stack\n");

   Stack.Parameters.FilterResourceRequirements.IoResourceRequirementList = DeviceNode->ResourceRequirements;
   Status = IopInitiatePnpIrp(
      DeviceNode->PhysicalDeviceObject,
      &IoStatusBlock,
      IRP_MN_FILTER_RESOURCE_REQUIREMENTS,
      &Stack);
   if (!NT_SUCCESS(Status) && Status != STATUS_NOT_SUPPORTED)
   {
      DPRINT1("IopInitiatePnpIrp(IRP_MN_FILTER_RESOURCE_REQUIREMENTS) failed\n");
      return Status;
   }
   else if (NT_SUCCESS(Status) && IoStatusBlock.Information)
   {
      DeviceNode->ResourceRequirements = (PIO_RESOURCE_REQUIREMENTS_LIST)IoStatusBlock.Information;
   }

   return STATUS_SUCCESS;
}


NTSTATUS
IopUpdateResourceMap(IN PDEVICE_NODE DeviceNode, PWCHAR Level1Key, PWCHAR Level2Key)
{
  NTSTATUS Status;
  ULONG Disposition;
  HANDLE PnpMgrLevel1, PnpMgrLevel2, ResourceMapKey;
  UNICODE_STRING KeyName;
  OBJECT_ATTRIBUTES ObjectAttributes;

  RtlInitUnicodeString(&KeyName,
               L"\\Registry\\Machine\\HARDWARE\\RESOURCEMAP");
  InitializeObjectAttributes(&ObjectAttributes,
                 &KeyName,
                 OBJ_CASE_INSENSITIVE | OBJ_OPENIF | OBJ_KERNEL_HANDLE,
                 NULL,
                 NULL);
  Status = ZwCreateKey(&ResourceMapKey,
               KEY_ALL_ACCESS,
               &ObjectAttributes,
               0,
               NULL,
               REG_OPTION_VOLATILE,
               &Disposition);
  if (!NT_SUCCESS(Status))
      return Status;

  RtlInitUnicodeString(&KeyName, Level1Key);
  InitializeObjectAttributes(&ObjectAttributes,
                 &KeyName,
                 OBJ_CASE_INSENSITIVE | OBJ_OPENIF | OBJ_KERNEL_HANDLE,
                 ResourceMapKey,
                 NULL);
  Status = ZwCreateKey(&PnpMgrLevel1,
                       KEY_ALL_ACCESS,
                       &ObjectAttributes,
                       0,
                       NULL,
                       REG_OPTION_VOLATILE,
                       &Disposition);
  ZwClose(ResourceMapKey);
  if (!NT_SUCCESS(Status))
      return Status;

  RtlInitUnicodeString(&KeyName, Level2Key);
  InitializeObjectAttributes(&ObjectAttributes,
                 &KeyName,
                 OBJ_CASE_INSENSITIVE | OBJ_OPENIF | OBJ_KERNEL_HANDLE,
                 PnpMgrLevel1,
                 NULL);
  Status = ZwCreateKey(&PnpMgrLevel2,
                       KEY_ALL_ACCESS,
                       &ObjectAttributes,
                       0,
                       NULL,
                       REG_OPTION_VOLATILE,
                       &Disposition);
  ZwClose(PnpMgrLevel1);
  if (!NT_SUCCESS(Status))
      return Status;

  if (DeviceNode->ResourceList)
  {
      UNICODE_STRING NameU;
      UNICODE_STRING RawSuffix, TranslatedSuffix;
      ULONG OldLength = 0;

      ASSERT(DeviceNode->ResourceListTranslated);

      RtlInitUnicodeString(&TranslatedSuffix, L".Translated");
      RtlInitUnicodeString(&RawSuffix, L".Raw");

      Status = IoGetDeviceProperty(DeviceNode->PhysicalDeviceObject,
                                   DevicePropertyPhysicalDeviceObjectName,
                                   0,
                                   NULL,
                                   &OldLength);
      if (Status == STATUS_BUFFER_OVERFLOW || Status == STATUS_BUFFER_TOO_SMALL)
      {
          ASSERT(OldLength);

          NameU.Buffer = ExAllocatePool(PagedPool, OldLength + TranslatedSuffix.Length);
          if (!NameU.Buffer)
          {
              ZwClose(PnpMgrLevel2);
              return STATUS_INSUFFICIENT_RESOURCES;
          }

          NameU.Length = 0;
          NameU.MaximumLength = (USHORT)OldLength + TranslatedSuffix.Length;

          Status = IoGetDeviceProperty(DeviceNode->PhysicalDeviceObject,
                                       DevicePropertyPhysicalDeviceObjectName,
                                       NameU.MaximumLength,
                                       NameU.Buffer,
                                       &OldLength);
          if (!NT_SUCCESS(Status))
          {
              ZwClose(PnpMgrLevel2);
              ExFreePool(NameU.Buffer);
              return Status;
          }
      }
      else if (!NT_SUCCESS(Status))
      {
          /* Some failure */
          ZwClose(PnpMgrLevel2);
          return Status;
      }
      else
      {
          /* This should never happen */
          ASSERT(FALSE);
      }

      NameU.Length = (USHORT)OldLength;

      RtlAppendUnicodeStringToString(&NameU, &RawSuffix);

      Status = ZwSetValueKey(PnpMgrLevel2,
                             &NameU,
                             0,
                             REG_RESOURCE_LIST,
                             DeviceNode->ResourceList,
                             PnpDetermineResourceListSize(DeviceNode->ResourceList));
      if (!NT_SUCCESS(Status))
      {
          ZwClose(PnpMgrLevel2);
          ExFreePool(NameU.Buffer);
          return Status;
      }

      /* "Remove" the suffix by setting the length back to what it used to be */
      NameU.Length = (USHORT)OldLength;

      RtlAppendUnicodeStringToString(&NameU, &TranslatedSuffix);

      Status = ZwSetValueKey(PnpMgrLevel2,
                             &NameU,
                             0,
                             REG_RESOURCE_LIST,
                             DeviceNode->ResourceListTranslated,
                             PnpDetermineResourceListSize(DeviceNode->ResourceListTranslated));
      ZwClose(PnpMgrLevel2);
      ExFreePool(NameU.Buffer);

      if (!NT_SUCCESS(Status))
          return Status;
  }
  else
  {
      ZwClose(PnpMgrLevel2);
  }

  return STATUS_SUCCESS;
}

NTSTATUS
IopUpdateResourceMapForPnPDevice(IN PDEVICE_NODE DeviceNode)
{
  return IopUpdateResourceMap(DeviceNode, L"PnP Manager", L"PnpManager");
}

static
NTSTATUS
IopTranslateDeviceResources(
   IN PDEVICE_NODE DeviceNode)
{
   PCM_PARTIAL_RESOURCE_LIST pPartialResourceList;
   PCM_PARTIAL_RESOURCE_DESCRIPTOR DescriptorRaw, DescriptorTranslated;
   ULONG i, j, ListSize;
   NTSTATUS Status;

   if (!DeviceNode->ResourceList)
   {
      DeviceNode->ResourceListTranslated = NULL;
      return STATUS_SUCCESS;
   }

   /* That's easy to translate a resource list. Just copy the
    * untranslated one and change few fields in the copy
    */
   ListSize = PnpDetermineResourceListSize(DeviceNode->ResourceList);

   DeviceNode->ResourceListTranslated = ExAllocatePool(PagedPool, ListSize);
   if (!DeviceNode->ResourceListTranslated)
   {
      Status = STATUS_NO_MEMORY;
      goto cleanup;
   }
   RtlCopyMemory(DeviceNode->ResourceListTranslated, DeviceNode->ResourceList, ListSize);

   for (i = 0; i < DeviceNode->ResourceList->Count; i++)
   {
      pPartialResourceList = &DeviceNode->ResourceList->List[i].PartialResourceList;
      for (j = 0; j < pPartialResourceList->Count; j++)
      {
         DescriptorRaw = &pPartialResourceList->PartialDescriptors[j];
         DescriptorTranslated = &DeviceNode->ResourceListTranslated->List[i].PartialResourceList.PartialDescriptors[j];
         switch (DescriptorRaw->Type)
         {
            case CmResourceTypePort:
            {
               ULONG AddressSpace = 1; /* IO space */
               if (!HalTranslateBusAddress(
                  DeviceNode->ResourceList->List[i].InterfaceType,
                  DeviceNode->ResourceList->List[i].BusNumber,
                  DescriptorRaw->u.Port.Start,
                  &AddressSpace,
                  &DescriptorTranslated->u.Port.Start))
               {
                  Status = STATUS_UNSUCCESSFUL;
                  DPRINT1("Failed to translate port resource (Start: 0x%I64x)\n", DescriptorRaw->u.Port.Start.QuadPart);
                  goto cleanup;
               }

               if (AddressSpace == 0)
               {
                   DPRINT1("Guessed incorrect address space: 1 -> 0\n");

                   /* FIXME: I think all other CM_RESOURCE_PORT_XXX flags are
                    * invalid for this state but I'm not 100% sure */
                   DescriptorRaw->Flags =
                   DescriptorTranslated->Flags = CM_RESOURCE_PORT_MEMORY;
               }
               break;
            }
            case CmResourceTypeInterrupt:
            {
               DescriptorTranslated->u.Interrupt.Vector = HalGetInterruptVector(
                  DeviceNode->ResourceList->List[i].InterfaceType,
                  DeviceNode->ResourceList->List[i].BusNumber,
                  DescriptorRaw->u.Interrupt.Level,
                  DescriptorRaw->u.Interrupt.Vector,
                  (PKIRQL)&DescriptorTranslated->u.Interrupt.Level,
                  &DescriptorTranslated->u.Interrupt.Affinity);

               if (!DescriptorTranslated->u.Interrupt.Vector)
               {
                   Status = STATUS_UNSUCCESSFUL;
                   DPRINT1("Failed to translate interrupt resource (Vector: 0x%x | Level: 0x%x)\n", DescriptorRaw->u.Interrupt.Vector,
                                                                                                   DescriptorRaw->u.Interrupt.Level);
                   goto cleanup;
               }
               break;
            }
            case CmResourceTypeMemory:
            {
               ULONG AddressSpace = 0; /* Memory space */
               if (!HalTranslateBusAddress(
                  DeviceNode->ResourceList->List[i].InterfaceType,
                  DeviceNode->ResourceList->List[i].BusNumber,
                  DescriptorRaw->u.Memory.Start,
                  &AddressSpace,
                  &DescriptorTranslated->u.Memory.Start))
               {
                  Status = STATUS_UNSUCCESSFUL;
                  DPRINT1("Failed to translate memory resource (Start: 0x%I64x)\n", DescriptorRaw->u.Memory.Start.QuadPart);
                  goto cleanup;
               }

               if (AddressSpace != 0)
               {
                   DPRINT1("Guessed incorrect address space: 0 -> 1\n");

                   /* This should never happen for memory space */
                   ASSERT(FALSE);
               }
            }

            case CmResourceTypeDma:
            case CmResourceTypeBusNumber:
            case CmResourceTypeDeviceSpecific:
               /* Nothing to do */
               break;
            default:
               DPRINT1("Unknown resource descriptor type 0x%x\n", DescriptorRaw->Type);
               Status = STATUS_NOT_IMPLEMENTED;
               goto cleanup;
         }
      }
   }
   return STATUS_SUCCESS;

cleanup:
   /* Yes! Also delete ResourceList because ResourceList and
    * ResourceListTranslated should be a pair! */
   ExFreePool(DeviceNode->ResourceList);
   DeviceNode->ResourceList = NULL;
   if (DeviceNode->ResourceListTranslated)
   {
      ExFreePool(DeviceNode->ResourceListTranslated);
      DeviceNode->ResourceList = NULL;
   }
   return Status;
}

NTSTATUS
NTAPI
IopAssignDeviceResources(
   IN PDEVICE_NODE DeviceNode)
{
   NTSTATUS Status;
   ULONG ListSize;

   IopDeviceNodeSetFlag(DeviceNode, DNF_ASSIGNING_RESOURCES);

   Status = IopFilterResourceRequirements(DeviceNode);
   if (!NT_SUCCESS(Status))
       goto ByeBye;

   if (!DeviceNode->BootResources && !DeviceNode->ResourceRequirements)
   {
      DeviceNode->Flags |= DNF_NO_RESOURCE_REQUIRED;
      DeviceNode->Flags &= ~DNF_ASSIGNING_RESOURCES;

      /* No resource needed for this device */
      DeviceNode->ResourceList = NULL;
      DeviceNode->ResourceListTranslated = NULL;

      return STATUS_SUCCESS;
   }

   if (DeviceNode->BootResources)
   {
       ListSize = PnpDetermineResourceListSize(DeviceNode->BootResources);

       DeviceNode->ResourceList = ExAllocatePool(PagedPool, ListSize);
       if (!DeviceNode->ResourceList)
       {
           Status = STATUS_NO_MEMORY;
           goto ByeBye;
       }

       RtlCopyMemory(DeviceNode->ResourceList, DeviceNode->BootResources, ListSize);

       Status = IopDetectResourceConflict(DeviceNode->ResourceList, FALSE, NULL);
       if (!NT_SUCCESS(Status))
       {
           DPRINT1("Boot resources for %wZ cause a resource conflict!\n", &DeviceNode->InstancePath);
           ExFreePool(DeviceNode->ResourceList);
           DeviceNode->ResourceList = NULL;
       }
   }
   else
   {
       /* We'll make this from the requirements */
       DeviceNode->ResourceList = NULL;
   }

   /* No resources requirements */
   if (!DeviceNode->ResourceRequirements)
       goto Finish;

   /* Call HAL to fixup our resource requirements list */
   HalAdjustResourceList(&DeviceNode->ResourceRequirements);

   /* Add resource requirements that aren't in the list we already got */
   Status = IopFixupResourceListWithRequirements(DeviceNode->ResourceRequirements,
                                                 &DeviceNode->ResourceList);
   if (!NT_SUCCESS(Status))
   {
       DPRINT1("Failed to fixup a resource list from supplied resources for %wZ\n", &DeviceNode->InstancePath);
       DeviceNode->Problem = CM_PROB_NORMAL_CONFLICT;
       goto ByeBye;
   }

   /* IopFixupResourceListWithRequirements should NEVER give us a conflicting list */
   ASSERT(IopDetectResourceConflict(DeviceNode->ResourceList, FALSE, NULL) != STATUS_CONFLICTING_ADDRESSES);

Finish:
   Status = IopTranslateDeviceResources(DeviceNode);
   if (!NT_SUCCESS(Status))
   {
       DeviceNode->Problem = CM_PROB_TRANSLATION_FAILED;
       DPRINT1("Failed to translate resources for %wZ\n", &DeviceNode->InstancePath);
       goto ByeBye;
   }

   Status = IopUpdateResourceMapForPnPDevice(DeviceNode);
   if (!NT_SUCCESS(Status))
       goto ByeBye;

   Status = IopUpdateControlKeyWithResources(DeviceNode);
   if (!NT_SUCCESS(Status))
       goto ByeBye;

   IopDeviceNodeSetFlag(DeviceNode, DNF_RESOURCE_ASSIGNED);

   IopDeviceNodeClearFlag(DeviceNode, DNF_ASSIGNING_RESOURCES);

   return STATUS_SUCCESS;

ByeBye:
   if (DeviceNode->ResourceList)
   {
      ExFreePool(DeviceNode->ResourceList);
      DeviceNode->ResourceList = NULL;
   }

   DeviceNode->ResourceListTranslated = NULL;

   IopDeviceNodeClearFlag(DeviceNode, DNF_ASSIGNING_RESOURCES);

   return Status;
}

static
BOOLEAN
IopCheckForResourceConflict(
   IN PCM_RESOURCE_LIST ResourceList1,
   IN PCM_RESOURCE_LIST ResourceList2,
   IN BOOLEAN Silent,
   OUT OPTIONAL PCM_PARTIAL_RESOURCE_DESCRIPTOR ConflictingDescriptor)
{
   ULONG i, ii;
   BOOLEAN Result = FALSE;

   for (i = 0; i < ResourceList1->Count; i++)
   {
      PCM_PARTIAL_RESOURCE_LIST ResList = &ResourceList1->List[i].PartialResourceList;
      for (ii = 0; ii < ResList->Count; ii++)
      {
         PCM_PARTIAL_RESOURCE_DESCRIPTOR ResDesc = &ResList->PartialDescriptors[ii];

         Result = IopCheckResourceDescriptor(ResDesc,
                                             ResourceList2,
                                             Silent,
                                             ConflictingDescriptor);
         if (Result) goto ByeBye;
      }
   }

ByeBye:

   return Result;
}

NTSTATUS NTAPI
IopDetectResourceConflict(
   IN PCM_RESOURCE_LIST ResourceList,
   IN BOOLEAN Silent,
   OUT OPTIONAL PCM_PARTIAL_RESOURCE_DESCRIPTOR ConflictingDescriptor)
{
   OBJECT_ATTRIBUTES ObjectAttributes;
   UNICODE_STRING KeyName;
   HANDLE ResourceMapKey = NULL, ChildKey2 = NULL, ChildKey3 = NULL;
   ULONG KeyInformationLength, RequiredLength, KeyValueInformationLength, KeyNameInformationLength;
   PKEY_BASIC_INFORMATION KeyInformation;
   PKEY_VALUE_PARTIAL_INFORMATION KeyValueInformation;
   PKEY_VALUE_BASIC_INFORMATION KeyNameInformation;
   ULONG ChildKeyIndex1 = 0, ChildKeyIndex2 = 0, ChildKeyIndex3 = 0;
   NTSTATUS Status;

   RtlInitUnicodeString(&KeyName, L"\\Registry\\Machine\\HARDWARE\\RESOURCEMAP");
   InitializeObjectAttributes(&ObjectAttributes,
                              &KeyName,
                              OBJ_CASE_INSENSITIVE | OBJ_KERNEL_HANDLE,
                              NULL,
                              NULL);
   Status = ZwOpenKey(&ResourceMapKey, KEY_ENUMERATE_SUB_KEYS | KEY_QUERY_VALUE, &ObjectAttributes);
   if (!NT_SUCCESS(Status))
   {
      /* The key is missing which means we are the first device */
      return STATUS_SUCCESS;
   }

   while (TRUE)
   {
      Status = ZwEnumerateKey(ResourceMapKey,
                              ChildKeyIndex1,
                              KeyBasicInformation,
                              NULL,
                              0,
                              &RequiredLength);
      if (Status == STATUS_NO_MORE_ENTRIES)
          break;
      else if (Status == STATUS_BUFFER_OVERFLOW || Status == STATUS_BUFFER_TOO_SMALL)
      {
          KeyInformationLength = RequiredLength;
          KeyInformation = ExAllocatePoolWithTag(PagedPool,
                                                 KeyInformationLength,
                                                 TAG_IO);
          if (!KeyInformation)
          {
              Status = STATUS_INSUFFICIENT_RESOURCES;
              goto cleanup;
          }

          Status = ZwEnumerateKey(ResourceMapKey,
                                  ChildKeyIndex1,
                                  KeyBasicInformation,
                                  KeyInformation,
                                  KeyInformationLength,
                                  &RequiredLength);
      }
      else
         goto cleanup;
      ChildKeyIndex1++;
      if (!NT_SUCCESS(Status))
      {
          ExFreePoolWithTag(KeyInformation, TAG_IO);
          goto cleanup;
      }

      KeyName.Buffer = KeyInformation->Name;
      KeyName.MaximumLength = KeyName.Length = (USHORT)KeyInformation->NameLength;
      InitializeObjectAttributes(&ObjectAttributes,
                                 &KeyName,
                                 OBJ_CASE_INSENSITIVE | OBJ_KERNEL_HANDLE,
                                 ResourceMapKey,
                                 NULL);
      Status = ZwOpenKey(&ChildKey2,
                         KEY_ENUMERATE_SUB_KEYS | KEY_QUERY_VALUE,
                         &ObjectAttributes);
      ExFreePoolWithTag(KeyInformation, TAG_IO);
      if (!NT_SUCCESS(Status))
          goto cleanup;

      while (TRUE)
      {
          Status = ZwEnumerateKey(ChildKey2,
                                  ChildKeyIndex2,
                                  KeyBasicInformation,
                                  NULL,
                                  0,
                                  &RequiredLength);
          if (Status == STATUS_NO_MORE_ENTRIES)
              break;
          else if (Status == STATUS_BUFFER_TOO_SMALL)
          {
              KeyInformationLength = RequiredLength;
              KeyInformation = ExAllocatePoolWithTag(PagedPool,
                                                     KeyInformationLength,
                                                     TAG_IO);
              if (!KeyInformation)
              {
                  Status = STATUS_INSUFFICIENT_RESOURCES;
                  goto cleanup;
              }

              Status = ZwEnumerateKey(ChildKey2,
                                      ChildKeyIndex2,
                                      KeyBasicInformation,
                                      KeyInformation,
                                      KeyInformationLength,
                                      &RequiredLength);
          }
          else
              goto cleanup;
          ChildKeyIndex2++;
          if (!NT_SUCCESS(Status))
          {
              ExFreePoolWithTag(KeyInformation, TAG_IO);
              goto cleanup;
          }

          KeyName.Buffer = KeyInformation->Name;
          KeyName.MaximumLength = KeyName.Length = (USHORT)KeyInformation->NameLength;
          InitializeObjectAttributes(&ObjectAttributes,
                                     &KeyName,
                                     OBJ_CASE_INSENSITIVE | OBJ_KERNEL_HANDLE,
                                     ChildKey2,
                                     NULL);
          Status = ZwOpenKey(&ChildKey3, KEY_QUERY_VALUE, &ObjectAttributes);
          ExFreePoolWithTag(KeyInformation, TAG_IO);
          if (!NT_SUCCESS(Status))
              goto cleanup;

          while (TRUE)
          {
              Status = ZwEnumerateValueKey(ChildKey3,
                                           ChildKeyIndex3,
                                           KeyValuePartialInformation,
                                           NULL,
                                           0,
                                           &RequiredLength);
              if (Status == STATUS_NO_MORE_ENTRIES)
                  break;
              else if (Status == STATUS_BUFFER_TOO_SMALL)
              {
                  KeyValueInformationLength = RequiredLength;
                  KeyValueInformation = ExAllocatePoolWithTag(PagedPool,
                                                              KeyValueInformationLength,
                                                              TAG_IO);
                  if (!KeyValueInformation)
                  {
                      Status = STATUS_INSUFFICIENT_RESOURCES;
                      goto cleanup;
                  }

                  Status = ZwEnumerateValueKey(ChildKey3,
                                               ChildKeyIndex3,
                                               KeyValuePartialInformation,
                                               KeyValueInformation,
                                               KeyValueInformationLength,
                                               &RequiredLength);
              }
              else
                  goto cleanup;
              if (!NT_SUCCESS(Status))
              {
                  ExFreePoolWithTag(KeyValueInformation, TAG_IO);
                  goto cleanup;
              }

              Status = ZwEnumerateValueKey(ChildKey3,
                                           ChildKeyIndex3,
                                           KeyValueBasicInformation,
                                           NULL,
                                           0,
                                           &RequiredLength);
              if (Status == STATUS_BUFFER_TOO_SMALL)
              {
                  KeyNameInformationLength = RequiredLength;
                  KeyNameInformation = ExAllocatePoolWithTag(PagedPool,
                                                             KeyNameInformationLength + sizeof(WCHAR),
                                                             TAG_IO);
                  if (!KeyNameInformation)
                  {
                      Status = STATUS_INSUFFICIENT_RESOURCES;
                      goto cleanup;
                  }

                  Status = ZwEnumerateValueKey(ChildKey3,
                                               ChildKeyIndex3,
                                               KeyValueBasicInformation,
                                               KeyNameInformation,
                                               KeyNameInformationLength,
                                               &RequiredLength);
              }
              else
                  goto cleanup;
              ChildKeyIndex3++;
              if (!NT_SUCCESS(Status))
              {
                  ExFreePoolWithTag(KeyNameInformation, TAG_IO);
                  goto cleanup;
              }

              KeyNameInformation->Name[KeyNameInformation->NameLength / sizeof(WCHAR)] = UNICODE_NULL;

              /* Skip translated entries */
              if (wcsstr(KeyNameInformation->Name, L".Translated"))
              {
                  ExFreePoolWithTag(KeyNameInformation, TAG_IO);
                  ExFreePoolWithTag(KeyValueInformation, TAG_IO);
                  continue;
              }

              ExFreePoolWithTag(KeyNameInformation, TAG_IO);

              if (IopCheckForResourceConflict(ResourceList,
                                              (PCM_RESOURCE_LIST)KeyValueInformation->Data,
                                              Silent,
                                              ConflictingDescriptor))
              {
                  ExFreePoolWithTag(KeyValueInformation, TAG_IO);
                  Status = STATUS_CONFLICTING_ADDRESSES;
                  goto cleanup;
              }

              ExFreePoolWithTag(KeyValueInformation, TAG_IO);
          }
      }
   }

cleanup:
   if (ResourceMapKey != NULL)
       ObCloseHandle(ResourceMapKey, KernelMode);
   if (ChildKey2 != NULL)
       ObCloseHandle(ChildKey2, KernelMode);
   if (ChildKey3 != NULL)
       ObCloseHandle(ChildKey3, KernelMode);

   if (Status == STATUS_NO_MORE_ENTRIES)
       Status = STATUS_SUCCESS;

   return Status;
}