MmFreeContiguousMemory function (ntddk.h)
The MmFreeContiguousMemory routine releases a range of physically contiguous memory that was allocated by an MmAllocateContiguousMemoryXxx routine.
void MmFreeContiguousMemory( PVOID BaseAddress );
[in] Pointer to the virtual address of the memory to be freed.
The MmFreeContiguousMemory routine frees a block of physically contiguous memory that was allocated by a previous call to the MmAllocateContiguousMemory, MmAllocateContiguousMemorySpecifyCache, or MmAllocateContiguousMemorySpecifyCacheNode routine. The BaseAddress parameter must be the base address that was obtained from the previous call to the MmAllocateContiguousMemoryXxx routine.
A device driver that must use contiguous memory should allocate only what it needs during driver initialization because physical memory is likely to become fragmented as the system runs. Such a driver must deallocate the memory when the driver is done using the memory.
Callers of MmFreeContiguousMemory must be running at IRQL = APC_LEVEL. For Windows Server 2008 and later versions of the Windows operating system, you can also call MmFreeContiguousMemory with IRQL <= DISPATCH_LEVEL. However, you can improve driver performance by calling at APC_LEVEL or below.
|Minimum supported client||Available starting with Windows 2000.|
|Header||ntddk.h (include Wdm.h, Ntddk.h)|
|IRQL||See Remarks section.|
|DDI compliance rules||IrqlMmDispatch, HwStorPortProhibitedDDIs|