MiPurgeSubsection

UINT64 __stdcall MiPurgeSubsection(_MSUBSECTION *MappedSubsection){
  UINT64 v1; 
  unsigned __int64 v2; 
  __int64 v4; 
  __int64 v5; 
  UINT8 v6; 
  unsigned int v7; 
  _MMPFN *v8; 
  _MMPFN *v9; 
  ULONG_PTR BugCheckParameter4; 
  UINT64 v11; 
  unsigned __int64 v12; 
  __int64 v13; 
  unsigned __int64 v14; 
  UINT64 v16; 
  UINT8 PageIrql; 
  UINT64 SpinCount; 
  __int64 v19; 
  unsigned __int64 v20; 
  v2 = *((_QWORD *)MappedSubsection + 1);
  v4 = *((unsigned int *)MappedSubsection + 11);
  v5 = *(_QWORD *)MappedSubsection;
  v6 = 17;
  v19 = *(_QWORD *)MappedSubsection;
  v7 = 1;
  PageIrql = 17;
  v8 = 0i64;
  v20 = v2 + 8 * v4;
  if( v2 >= v20 )
    return v7;
  while( (v2 & 0xFFF) == 0 || v6 == 17 )
  {
    if( v6 != 17 )
    {
      LOBYTE(v1) = v6;
      MiUnlockProtoPoolPage(v8, v1);
    }
    v8 = MiCheckProtoPtePageState((_MMPTE *)v2, &PageIrql);
    if( v8 )
    {
      ExAcquireSpinLockExclusiveAtDpcLevel((INT64 *)(v5 + 72));
      if( *((_QWORD *)MappedSubsection + 12) != 1i64 || (*((_BYTE *)MappedSubsection + 32) & 1) != 0 )
      {
        ExReleaseSpinLockExclusiveFromDpcLevel((INT64 *)(v5 + 72));
        LOBYTE(v16) = PageIrql;
        MiUnlockProtoPoolPage(v8, v16);
        return 0i64;
      }
      ExReleaseSpinLockExclusiveFromDpcLevel((INT64 *)(v5 + 72));
      v6 = PageIrql;
      break;
    }
    v2 = (v2 & 0xFFFFFFFFFFFFF000ui64) + 4096;
LABEL_26:
    v6 = PageIrql;
LABEL_27:
    if( v2 >= v20 )
      goto LABEL_31;
  }
  v9 = MiLockLeafPage((_MMPTE *)v2, 0i64);
  BugCheckParameter4 = MI_READ_PTE_LOCK_FREE(v2);
  v12 = BugCheckParameter4;
  if( !v9 )
  {
    if( (BugCheckParameter4 & 0xC00) == 0 && BugCheckParameter4 )
      KeBugCheckEx(0xDEu, 4ui64, (ULONG_PTR)MappedSubsection, v2, BugCheckParameter4);
    v2 += 8i64;
    goto LABEL_27;
  }
  if( (BugCheckParameter4 & 1) == 0 )
  {
    if( qword_140C4DC80 )
    {
      if( (BugCheckParameter4 & 0x10) != 0 )
        v12 = BugCheckParameter4 & 0xFFFFFFFFFFFFFFEFui64;
      else
        v12 = ~qword_140C4DC80 & BugCheckParameter4;
    }
    v13 = (v12 >> 12) & 0xFFFFFFFFFi64;
    v9 = (_MMPFN *)((char *)MmGetPfnDb() + 48 * v13);
    if( (*((_BYTE *)v9 + 34) & 0x10) == 0 && !*((_WORD *)v9 + 16) )
    {
      MiDereferenceControlAreaPfnList((_CONTROL_AREA *)v5, (_SUBSECTION *)MappedSubsection, v11, 2ui64);
      *(_QWORD *)v2 = *((_QWORD *)v9 + 2);
      MiUnlinkPageFromList(v9, 0i64);
      MiInsertPageInFreeOrZeroedList(v13, 2ui64);
      _InterlockedAnd64((volatile signed __int64 *)v9 + 3, 0x7FFFFFFFFFFFFFFFui64);
      LODWORD(SpinCount) = 0;
      while( _interlockedbittestandset64((volatile signed __int32 *)v8 + 6, 0x3Fui64) )
      {
        do
          KeYieldProcessorEx(&SpinCount);
        while( *((__int64 *)v8 + 3) < 0 );
      }
      MiDecrementShareCount((UINT64)v8);
      _InterlockedAnd64((volatile signed __int64 *)v8 + 3, 0x7FFFFFFFFFFFFFFFui64);
      v5 = v19;
      v2 += 8i64;
      goto LABEL_26;
    }
  }
  _InterlockedAnd64((volatile signed __int64 *)v9 + 3, 0x7FFFFFFFFFFFFFFFui64);
  v6 = PageIrql;
  v7 = 0;
LABEL_31:
  if( v6 != 17 )
  {
    LOBYTE(v1) = v6;
    MiUnlockProtoPoolPage(v8, v1);
  }
  if( !v7 )
  {
    v14 = ExAcquireSpinLockExclusive((PEX_SPIN_LOCK)(v5 + 72));
    *((_WORD *)MappedSubsection + 16) |= 1u;
    ExReleaseSpinLockExclusiveFromDpcLevel((INT64 *)(v5 + 72));
    __writecr8(v14);
  }
  return v7;
}

Referenced by: