PfLockSharedTryAcquire

INT64 __fastcall PfLockSharedTryAcquire(UINT64 Lock){
  _ETHREAD *CurrentThread; 
  _ETHREAD *v3; 
  __int64 v4; 
  char v5; 
  __int64 v6; 
  int SessionId; 
  bool v8; 
  unsigned int v10; 
  CurrentThread = (_ETHREAD *)KeGetCurrentThread();
  --*((_WORD *)CurrentThread + 242);
  v10 = 0;
  v3 = (_ETHREAD *)KeGetCurrentThread();
  --*((_WORD *)v3 + 243);
  if( ++*((_BYTE *)v3 + 794) != 1 )
  {
    v6 = 0i64;
    goto LABEL_9;
  }
  LOBYTE(v4) = *((_BYTE *)v3 + 792);
  if( !(_BYTE)v4 )
  {
    if( !*((_BYTE *)v3 + 870) )
    {
      v6 = 0i64;
      goto LABEL_9;
    }
    v4 = *((unsigned __int8 *)v3 + 870);
    *((_BYTE *)v3 + 870) = 0;
    LOBYTE(v4) = *((_BYTE *)v3 + 792) | v4;
  }
  v5 = v4;
  _BitScanForward((unsigned int *)&v4, (unsigned __int8)v4);
  *((_BYTE *)v3 + 792) = v5 & ~(1 << v4);
  v6 = *((_QWORD *)v3 + 100) + 96 * v4;
  if( !v6 )
  {
LABEL_9:
    _interlockedbittestandset((volatile signed __int32 *)v3 + 30, 0x10u);
    goto LABEL_10;
  }
  if( Lock >= 0xFFFF800000000000ui64 && *((_BYTE *)&antNameB + ((Lock >> 39) & 0x1FF) - 256) == 1 )
    SessionId = MmGetSessionIdEx(*((_QWORD *)v3 + 23));
  else
    SessionId = -1;
  *(_DWORD *)(v6 + 40) = SessionId;
  *(_QWORD *)(v6 + 32) = Lock & 0x7FFFFFFFFFFFFFFCi64;
LABEL_10:
  --*((_BYTE *)v3 + 794);
  KiAbThreadRemoveBoosts((ULONG_PTR)v3, Lock, &v10);
  v8 = (*((_WORD *)v3 + 243))++ == 0xFFFF;
  if( v8 && *((_ETHREAD **)v3 + 19) != (_ETHREAD *)((char *)v3 + 152) )
    KiCheckForKernelApcDelivery();
  if( !_InterlockedCompareExchange64((volatile signed __int64 *)Lock, 17i64, 0i64)
    || ExfTryAcquirePushLockShared((UINT64 *)Lock) )
  {
    if( v6 )
      *(_BYTE *)(v6 + 26) |= 1u;
    return 1i64;
  }
  else
  {
    if( v6 )
      KeAbPostReleaseEx((PVOID)Lock, (PVOID)v6);
    KeLeaveCriticalRegion();
    return 0i64;
  }
}

Referenced by: