MmGetSystemAddressForMdl

PVOID
    MmGetSystemAddressForMdl(
        IN PMDL  Mdl
        );

MmGetSystemAddressForMdl 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.

Parameters

Mdl

Points to a buffer whose corresponding base virtual address is to be mapped.

Return Value

MmGetSystemAddressForMdl returns the base system-space virtual address that maps the physical pages described by the given MDL.

Comments

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.

A caller running at IRQL DISPATCH_LEVEL must supply an MDL that maps nonpageable virtual addresses. 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, noncached memory, or a zone buffer.

The returned base address has the same offset as the virtual address in the MDL.

Callers of MmGetSystemAddressForMdl must be running at IRQL <= DISPATCH_LEVEL.

See Also

MmBuildMdlForNonPagedPool, MmProbeAndLockPages