VPCI_WRITE_BLOCK_INPUT structure (vpci.h)

The VPCI_WRITE_BLOCK_INPUT structure is used in an IOCTL_VPCI_WRITE_BLOCK IOCTL request to write data to a specified configuration block for a PCI Express (PCIe) virtual function (VF).

This IOCTL request is issued by the driver of a PCIe VF on a device that supports the single root I/O virtualization (SR-IOV) interface.

Syntax

typedef struct _VPCI_WRITE_BLOCK_INPUT {
  ULONG BlockId;
  ULONG DataLength;
  UCHAR Data[ANYSIZE_ARRAY];
} VPCI_WRITE_BLOCK_INPUT, *PVPCI_WRITE_BLOCK_INPUT;

Members

BlockId

A ULONG value that specifies the VF configuration block to be read. This value is defined by the driver for the PCIe physical function (PF) of the device.

DataLength

The size, in bytes, of the data to be written from the Data member.

Data[ANYSIZE_ARRAY]

A variable-size array that contains the data to be written to the configuration block that is specified by the BlockId member.

Remarks

A VF configuration block is used for backchannel communication between the drivers of the PCIe PF and a VF on a device that supports the SR-IOV interface. Data from a VF configuration block can be exchanged between the following drivers:

• The VF driver, which runs in the guest operating system. This operating system runs within a Hyper-V child partition.
• The PF driver, which runs in the management operating system.

  This operating system runs within the Hyper-V parent partition.

Requirements

See also

IOCTL_VPCI_WRITE_BLOCK