MiFreeUnusedPfnPages

VOID __stdcall MiFreeUnusedPfnPages(PVOID Context){
  ULONG_PTR *v1; 
  unsigned int SessionId; 
  _ETHREAD *CurrentThread; 
  ULONG_PTR v5; 
  _ETHREAD *v6; 
  char v7; 
  int v8; 
  bool v9; 
  __int64 v10; 
  unsigned __int64 v11; 
  __int64 v12; 
  _ETHREAD *v13; 
  unsigned int v14; 
  char v15; 
  int v16; 
  __int64 v17; 
  unsigned __int64 v18; 
  __int64 v19; 
  char v20; 
  int v21; 
  __int64 v22; 
  unsigned __int64 v23; 
  __int64 v24; 
  int v25; 
  _ETHREAD *v26; 
  __int64 Contexta[2]; 
  int v28; 
  int v29; 
  __int128 PcValue[6]; 
  int v31; 
  int v32; 
  int v33; 
  int v34; 
  v29 = 0;
  v1 = &MiSystemPartition;
  v28 = 0;
  Contexta[0] = (__int64)Context;
  Contexta[1] = (__int64)PcValue;
  if( Context )
    v1 = (ULONG_PTR *)Context;
  memset(PcValue, 0, 32);
  SessionId = -1;
  CurrentThread = (_ETHREAD *)KeGetCurrentThread();
  v26 = CurrentThread;
  v5 = (ULONG_PTR)(v1 + 24);
  while( 1 )
  {
    --*((_WORD *)CurrentThread + 243);
    ExAcquirePushLockExclusiveEx((UINT64)(v1 + 24), 0i64);
    if( !Context && *((_BYTE *)v1 + 204) == 1 )
    {
      if( (_InterlockedExchangeAdd64((volatile signed __int64 *)v5, 0xFFFFFFFFFFFFFFFFui64) & 6) == 2 )
        ExfTryToWakePushLock((volatile INT64 *)v1 + 24);
      v34 = 0;
      v6 = (_ETHREAD *)KeGetCurrentThread();
      if( (unsigned int)MiGetSystemRegionType((UINT64)(v1 + 24)) == 1 )
        SessionId = MmGetSessionIdEx(*((_QWORD *)v6 + 23));
      --*((_WORD *)v6 + 243);
      v20 = ++*((_BYTE *)v6 + 794);
      v21 = (*((char *)v6 + 792) | *((char *)v6 + 870)) ^ 0x3F;
      while( 1 )
      {
        v9 = !_BitScanReverse((unsigned int *)&v22, v21);
        v33 = v22;
        if( v9 )
          break;
        v23 = *((_QWORD *)v6 + 100) + 96 * v22;
        v21 &= ~(1 << v22);
        if( (*(_BYTE *)(v23 + 26) & 1) != 0
          && (*(_DWORD *)(v23 + 32) & 1) == 0
          && (*(_QWORD *)(v23 + 32) & 0x7FFFFFFFFFFFFFFCi64) == (v5 & 0x7FFFFFFFFFFFFFFCi64)
          && *(_DWORD *)(v23 + 40) == SessionId )
        {
          *(_BYTE *)(v23 + 26) &= ~1u;
          if( *(_QWORD *)(v23 + 32) )
          {
            if( v23 )
            {
              *(_BYTE *)(v23 + 32) |= 2u;
              if( *(__int64 *)(v23 + 32) < 0 )
                KiAbEntryRemoveFromTree(v23);
              v34 = *(_DWORD *)(v23 + 88) & 0x1FFFF;
              *(_DWORD *)(v23 + 88) &= 0xFFFE0000;
              *(_BYTE *)(v23 + 25) &= ~1u;
              *(_QWORD *)(v23 + 32) = 0i64;
              v24 = (__int64)(v23 - *((_QWORD *)v6 + 100)) / 96;
              if( v20 == 1 )
                *((_BYTE *)v6 + 792) |= 1 << v24;
              else
                _InterlockedOr8((volatile signed __int8 *)v6 + 870, 1 << v24);
              goto LABEL_74;
            }
            break;
          }
        }
      }
      if( (*((_DWORD *)v6 + 30) & 0x10000) == 0 )
        KeBugCheckEx(0x162u, (ULONG_PTR)v6, v5, SessionId, 0i64);
LABEL_74:
      --*((_BYTE *)v6 + 794);
      KiAbThreadRemoveBoosts((ULONG_PTR)v6, v5, (unsigned int *)&v34);
      v9 = (*((_WORD *)v6 + 243))++ == 0xFFFF;
      if( !v9 )
        goto LABEL_25;
LABEL_27:
      if( *((_ETHREAD **)v6 + 19) != (_ETHREAD *)((char *)v6 + 152) )
        KiCheckForKernelApcDelivery();
      goto LABEL_25;
    }
    KeGenericCallDpc((PKDEFERRED_ROUTINE)MiFreeUnusedPfnPagesDpc, Contexta);
    if( v28 != 259 )
      break;
    if( (_InterlockedExchangeAdd64((volatile signed __int64 *)v5, 0xFFFFFFFFFFFFFFFFui64) & 6) == 2 )
      ExfTryToWakePushLock((volatile INT64 *)v1 + 24);
    v31 = 0;
    v13 = (_ETHREAD *)KeGetCurrentThread();
    if( (unsigned int)MiGetSystemRegionType((UINT64)(v1 + 24)) == 1 )
      v14 = MmGetSessionIdEx(*((_QWORD *)v13 + 23));
    else
      v14 = -1;
    --*((_WORD *)v13 + 243);
    v15 = ++*((_BYTE *)v13 + 794);
    v16 = (*((char *)v13 + 792) | *((char *)v13 + 870)) ^ 0x3F;
    while( 1 )
    {
      v9 = !_BitScanReverse((unsigned int *)&v17, v16);
      v32 = v17;
      if( v9 )
        break;
      v18 = *((_QWORD *)v13 + 100) + 96 * v17;
      v16 &= ~(1 << v17);
      if( (*(_BYTE *)(v18 + 26) & 1) != 0
        && (*(_DWORD *)(v18 + 32) & 1) == 0
        && (*(_QWORD *)(v18 + 32) & 0x7FFFFFFFFFFFFFFCi64) == (v5 & 0x7FFFFFFFFFFFFFFCi64)
        && *(_DWORD *)(v18 + 40) == v14 )
      {
        *(_BYTE *)(v18 + 26) &= ~1u;
        if( *(_QWORD *)(v18 + 32) )
        {
          if( v18 )
          {
            *(_BYTE *)(v18 + 32) |= 2u;
            if( *(__int64 *)(v18 + 32) < 0 )
              KiAbEntryRemoveFromTree(v18);
            v31 = 0;
            v31 = *(_DWORD *)(v18 + 88) & 0x1FFFF;
            *(_DWORD *)(v18 + 88) &= 0xFFFE0000;
            *(_BYTE *)(v18 + 25) &= ~1u;
            *(_QWORD *)(v18 + 32) = 0i64;
            v19 = (__int64)(v18 - *((_QWORD *)v13 + 100)) / 96;
            if( v15 == 1 )
              *((_BYTE *)v13 + 792) |= 1 << v19;
            else
              _InterlockedOr8((volatile signed __int8 *)v13 + 870, 1 << v19);
            goto LABEL_49;
          }
          break;
        }
      }
    }
    if( (*((_DWORD *)v13 + 30) & 0x10000) == 0 )
      KeBugCheckEx(0x162u, (ULONG_PTR)v13, (ULONG_PTR)(v1 + 24), v14, 0i64);
LABEL_49:
    --*((_BYTE *)v13 + 794);
    KiAbThreadRemoveBoosts((ULONG_PTR)v13, (__int64)(v1 + 24), (unsigned int *)&v31);
    v9 = (*((_WORD *)v13 + 243))++ == 0xFFFF;
    if( v9 && *((_ETHREAD **)v13 + 19) != (_ETHREAD *)((char *)v13 + 152) )
      KiCheckForKernelApcDelivery();
    CurrentThread = v26;
    KiLeaveGuardedRegionUnsafe((__int64)v26);
    if( !Contexta[0] )
      return;
    KeWaitForGate((char *)PcValue + 8, 18);
  }
  v1[10] = 0i64;
  *((_BYTE *)v1 + 204) = 0;
  if( (_InterlockedExchangeAdd64((volatile signed __int64 *)v5, 0xFFFFFFFFFFFFFFFFui64) & 6) == 2 )
    ExfTryToWakePushLock((volatile INT64 *)v1 + 24);
  v25 = 0;
  v6 = (_ETHREAD *)KeGetCurrentThread();
  if( (unsigned int)MiGetSystemRegionType((UINT64)(v1 + 24)) == 1 )
    SessionId = MmGetSessionIdEx(*((_QWORD *)v6 + 23));
  --*((_WORD *)v6 + 243);
  v7 = ++*((_BYTE *)v6 + 794);
  v8 = (*((char *)v6 + 792) | *((char *)v6 + 870)) ^ 0x3F;
  while( 1 )
  {
    v9 = !_BitScanReverse((unsigned int *)&v10, v8);
    if( v9 )
      break;
    v11 = *((_QWORD *)v6 + 100) + 96 * v10;
    v8 &= ~(1 << v10);
    if( (*(_BYTE *)(v11 + 26) & 1) != 0
      && (*(_DWORD *)(v11 + 32) & 1) == 0
      && (*(_QWORD *)(v11 + 32) & 0x7FFFFFFFFFFFFFFCi64) == (v5 & 0x7FFFFFFFFFFFFFFCi64)
      && *(_DWORD *)(v11 + 40) == SessionId )
    {
      *(_BYTE *)(v11 + 26) &= ~1u;
      if( *(_QWORD *)(v11 + 32) )
      {
        if( v11 )
        {
          *(_BYTE *)(v11 + 32) |= 2u;
          if( *(__int64 *)(v11 + 32) < 0 )
            KiAbEntryRemoveFromTree(v11);
          v25 = *(_DWORD *)(v11 + 88) & 0x1FFFF;
          *(_DWORD *)(v11 + 88) &= 0xFFFE0000;
          *(_BYTE *)(v11 + 25) &= ~1u;
          *(_QWORD *)(v11 + 32) = 0i64;
          v12 = (__int64)(v11 - *((_QWORD *)v6 + 100)) / 96;
          if( v7 == 1 )
            *((_BYTE *)v6 + 792) |= 1 << v12;
          else
            _InterlockedOr8((volatile signed __int8 *)v6 + 870, 1 << v12);
          goto LABEL_24;
        }
        break;
      }
    }
  }
  if( (*((_DWORD *)v6 + 30) & 0x10000) == 0 )
    KeBugCheckEx(0x162u, (ULONG_PTR)v6, v5, SessionId, 0i64);
LABEL_24:
  --*((_BYTE *)v6 + 794);
  KiAbThreadRemoveBoosts((ULONG_PTR)v6, v5, (unsigned int *)&v25);
  v9 = (*((_WORD *)v6 + 243))++ == 0xFFFF;
  if( v9 )
    goto LABEL_27;
LABEL_25:
  KiLeaveGuardedRegionUnsafe((__int64)CurrentThread);
}

Referenced by:

MiInitNucleus