MmGetSystemAddressForMdl macro (wdm.h)
The MmGetSystemAddressForMdl routine is obsolete. Use MmGetSystemAddressForMdlSafe instead.
MmGetSystemAddressForMdl is a macro that returns a nonpaged system-space virtual address for the buffer described by the MDL. It maps the physical pages described by a given MDL into system space, if they are not already mapped to system space.
Syntax
PVOID MmGetSystemAddressForMdl(
MDL
);
Parameters
[in] MDL
Pointer to a buffer whose corresponding base virtual address is to be mapped.
Return value
None
Remarks
MmGetSystemAddressForMdl returns the base system-space virtual address that maps the physical pages described by the given MDL.
Drivers of PIO devices call this routine to translate a virtual address range, described by the MDL at Irp->MdlAddress, for a user buffer to a system-space address range.
The MDL must describe nonpageable memory. In other words, the input MDL must describe an already locked-down user-space buffer returned by MmProbeAndLockPages, a locked-down buffer returned by MmBuildMdlForNonPagedPool, or system-space memory allocated from nonpaged pool, contiguous memory, or non-cached memory.
The returned base address has the same offset as the virtual address in the MDL.
Window issues a bug check if the attempt to map to system space fails. Therefore, you should use MmGetSystemAddressForMdlSafe instead).
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Obsolete. Use MmGetSystemAddressForMdlSafe instead. |
| Target Platform | Desktop |
| Header | wdm.h (include Wdm.h, Ntddk.h, Ntifs.h) |
| IRQL | IRQL <= DISPATCH_LEVEL |