ZwUnmapViewOfSection function (wdm.h)
The ZwUnmapViewOfSection routine unmaps a view of a section from the virtual address space of a subject process.
Syntax
NTSYSAPI NTSTATUS ZwUnmapViewOfSection(
[in] HANDLE ProcessHandle,
[in, optional] PVOID BaseAddress
);
Parameters
[in] ProcessHandle
Handle to a process object that was previously passed to ZwMapViewOfSection.
[in, optional] BaseAddress
Pointer to the base virtual address of the view to unmap. This value can be any virtual address within the view.
Return value
ZwUnmapViewOfSection returns an NTSTATUS value. Possible return values include:
Return code | Description |
---|---|
STATUS_SUCCESS | The routine successfully performed the requested operation. |
STATUS_ACCESS_DENIED | The caller does not have access rights to the process object or to the base virtual address of the view. |
Remarks
This routine unmaps the entire view of the section that contains BaseAddress from the virtual address space of the specified process—even if BaseAddress does not point to the beginning of the view.
On return from ZwUnmapViewOfSection, the virtual-address region occupied by the view is no longer reserved and is available to map other views or private pages. If the view was also the last reference to the underlying section, all committed pages in the section are decommitted, and the section is deleted.
If the call to this function occurs in user mode, you should use the name "NtUnmapViewOfSection" instead of "ZwUnmapViewOfSection".
For calls from kernel-mode drivers, the NtXxx and ZwXxx versions of a Windows Native System Services routine can behave differently in the way that they handle and interpret input parameters. For more information about the relationship between the NtXxx and ZwXxx versions of a routine, see Using Nt and Zw Versions of the Native System Services Routines.
Requirements
Requirement | Value |
---|---|
Target Platform | Universal |
Header | wdm.h (include Wdm.h, Ntddk.h, Ntifs.h) |
Library | NtosKrnl.lib |
DLL | NtosKrnl.exe |
IRQL | PASSIVE_LEVEL |
DDI compliance rules | HwStorPortProhibitedDDIs(storport), PowerIrpDDis(wdm) |
See also
Using Nt and Zw Versions of the Native System Services Routines