DXGKARGCB_CREATE_PHYSICAL_MEMORY_OBJECT structure (d3dkmddi.h)
The DXGKARGCB_CREATE_PHYSICAL_MEMORY_OBJECT structure contains the information used by the DXGKCB_CREATEPHYSICALMEMORYOBJECT callback function to create physical memory.
Syntax
typedef struct _DXGKARGCB_CREATE_PHYSICAL_MEMORY_OBJECT {
HANDLE hAdapter;
SIZE_T Size;
ULONG_PTR Context;
DXGK_PHYSICAL_MEMORY_TYPE Type;
DXGK_MEMORY_CACHING_TYPE CacheType;
union {
struct {
PHYSICAL_ADDRESS LowAddress;
PHYSICAL_ADDRESS HighAddress;
PHYSICAL_ADDRESS SkipBytes;
UINT Flags;
} Mdl;
struct {
PHYSICAL_ADDRESS LowestAcceptableAddress;
PHYSICAL_ADDRESS HighestAcceptableAddress;
PHYSICAL_ADDRESS BoundaryAddressMultiple;
} ContiguousMemory;
struct {
ACCESS_MASK DesiredAccess;
POBJECT_ATTRIBUTES ObjectAttributes;
ULONG PageProtection;
ULONG AllocationAttributes;
} Section;
struct {
PHYSICAL_ADDRESS BaseAddress;
} IOSpace;
};
HANDLE hPhysicalMemoryObject;
HANDLE hAdapterMemoryObject;
} DXGKARGCB_CREATE_PHYSICAL_MEMORY_OBJECT;
Members
hAdapter
The adapter for which this physical memory will be associated. This parameter is optional and can be NULL. If it is NULL, the driver must call DXGKCB_OPENPHYSICALMEMORYOBJECT before creating an address descriptor list (ADL). See Remarks for more information.
Size
The size, in bytes, of the physical memory being requested. If Type is DXGK_PHYSICAL_MEMORY_TYPE_IO_SPACE, Size refers to the size of the IO space region provided by the driver.
Context
A pointer-size piece of context data that Dxgkrnl will store alongside the physical memory object for debugging purposes. This value is never directly used or dereferenced by Dxgkrnl in any way. This may be any value of the driver's choosing, such as the memory address to a driver-owned object that owns this physical memory object.
Type
A DXGK_PHYSICAL_MEMORY_TYPE value that specifies the type of physical memory to create. If Type is DXGK_PHYSICAL_MEMORY_TYPE_SECTION, then the allocation attributes of the section object are always SEC_COMMIT (PF-mapped section), and the cache type is determines by CacheType.
CacheType
The cache type of the pages. If Type is DXGK_PHYSICAL_MEMORY_TYPE_SECTION, CacheType must be either cached, or write-combined.
Mdl
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_MDL.
Mdl.LowAddress
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_MDL. See MmAllocatePagesForMdlEx for details.
Mdl.HighAddress
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_MDL. See MmAllocatePagesForMdlEx for details.
Mdl.SkipBytes
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_MDL. See MmAllocatePagesForMdlEx for details.
Mdl.Flags
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_MDL. See MmAllocatePagesForMdlEx for details.
ContiguousMemory
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_CONTIGUOUS_MEMORY.
ContiguousMemory.LowestAcceptableAddress
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_CONTIGUOUS_MEMORY. See MmAllocateContiguousMemorySpecifyCache for details.
ContiguousMemory.HighestAcceptableAddress
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_CONTIGUOUS_MEMORY. See MmAllocateContiguousMemorySpecifyCache for details.
ContiguousMemory.BoundaryAddressMultiple
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_CONTIGUOUS_MEMORY. See MmAllocateContiguousMemorySpecifyCache for details.
Section
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_SECTION.
Section.DesiredAccess
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_SECTION. See ZwCreateSection for details.
Section.ObjectAttributes
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_SECTION. See ZwCreateSection for details.
Section.PageProtection
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_SECTION. This value should be one of the following values: PAGE_READONLY, PAGE_READWRITE, PAGE_EXECUTE, or PAGE_WRITECOPY. Do not specify cache attributes (e.g. SEC_WRITECOMBINED) in this field. The allocated attributes of the section object are always SEC_COMMIT (PF-mapped section), and the cache type is determines by CacheType. See ZwCreateSection for details.
Section.AllocationAttributes
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_SECTION. See ZwCreateSection for details.
IOSpace
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_IO_SPACE.
IOSpace.BaseAddress
Used only when Type is DXGK_PHYSICAL_MEMORY_TYPE_IO_SPACE. Specifies the starting physical address of the IO space region. This value must be aligned to a multiple of PAGE_SIZE.
hPhysicalMemoryObject
On a successful call to DXGKCB_CREATEPHYSICALMEMORYOBJECT, this is an opaque handle back to a Dxgkrnl-managed physical memory object. The physical memory object can be provided to other documented memory management functions to map a virtual address for CPU access. This handle can be closed by calling DXGKCB_DESTROYPHYSICALMEMORYOBJECT.
hAdapterMemoryObject
On a successful call to DXGKCB_CREATEPHYSICALMEMORYOBJECT, this is an opaque handle back to a Dxgkrnl-managed adapter memory object. The adapter memory object can be provided to other documented memory management functions to generate an ADL for GPU access. If hAdapter is NULL, this value will be NULL and the driver must call DXGKCB_OPENPHYSICALMEMORYOBJECT to create this handle. This handle can be closed by calling DXGKCB_CLOSEPHYSICALMEMORYOBJECT, or may be provided to DXGKCB_DESTROYPHYSICALMEMORYOBJECT (but not both).
Remarks
The hAdapter field is optional when creating a physical memory object, but that object must be opened against an adapter in a call to DXGKCB_OPENPHYSICALMEMORYOBJECT before an ADL can be created. This is because an ADL represents logical memory, and each logical adapter has a unique domain. It does not matter which physical adapter the memory is created against. It will be opened by the logical adapter that the physical adapter belongs to and will be mapped to all linked physical adapters.
See IOMMU DMA remapping for more information.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported server | Windows Server 2022 (WDDM 2.9) |
| Header | d3dkmddi.h |
See also
DXGKCB_CLOSEPHYSICALMEMORYOBJECT
DXGKCB_CREATEPHYSICALMEMORYOBJECT
DXGKCB_DESTROYPHYSICALMEMORYOBJECT
DXGKCB_OPENPHYSICALMEMORYOBJECT
Feedback
Coming soon: Throughout 2024 we will be phasing out GitHub Issues as the feedback mechanism for content and replacing it with a new feedback system. For more information see: https://aka.ms/ContentUserFeedback.
Submit and view feedback for