DEVICE_COPY_OFFLOAD_DESCRIPTOR structure (ntddstor.h)
Used in conjunction with the IOCTL_STORAGE_QUERY_PROPERTY request to describe the copy offload capabilities of a storage device.
Syntax
typedef struct _DEVICE_COPY_OFFLOAD_DESCRIPTOR {
ULONG Version;
ULONG Size;
ULONG MaximumTokenLifetime;
ULONG DefaultTokenLifetime;
ULONGLONG MaximumTransferSize;
ULONGLONG OptimalTransferCount;
ULONG MaximumDataDescriptors;
ULONG MaximumTransferLengthPerDescriptor;
ULONG OptimalTransferLengthPerDescriptor;
USHORT OptimalTransferLengthGranularity;
UCHAR Reserved[2];
} DEVICE_COPY_OFFLOAD_DESCRIPTOR, *PDEVICE_COPY_OFFLOAD_DESCRIPTOR;
Members
Version
Contains the size of this structure, in bytes. The value of this member will change as members are added to the structure.
Size
Specifies the total size of the data returned, in bytes. This may include data that follows this structure.
MaximumTokenLifetime
The maximum lifetime of the token, in seconds.
DefaultTokenLifetime
The default lifetime of the token, in seconds.
MaximumTransferSize
The maximum transfer size, in bytes.
OptimalTransferCount
The optimal transfer size, in bytes.
MaximumDataDescriptors
The maximum number of data descriptors.
MaximumTransferLengthPerDescriptor
The maximum transfer length, in blocks, per descriptor.
OptimalTransferLengthPerDescriptor
The optimal transfer length, in blocks, per descriptor.
OptimalTransferLengthGranularity
The granularity of the optimal transfer length, in blocks. Transfer lengths that are not an even multiple of this length may be delayed.
Reserved[2]
Reserved for future use.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 8 |
| Minimum supported server | Windows Server 2012 |
| Header | ntddstor.h (include Ntddstor.h) |