NVME_COMMAND_DWORD0 union (nvme.h)

Contains parameters that are common for all Admin commands and NVM commands.

This structure is used in the CDW0 field of the NVME_COMMAND structure.

Syntax

typedef union {
  struct {
    ULONG OPC : 8;
    ULONG FUSE : 2;
    ULONG Reserved0 : 5;
    ULONG PSDT : 1;
    ULONG CID : 16;
  } DUMMYSTRUCTNAME;
  ULONG  AsUlong;
} NVME_COMMAND_DWORD0, *PNVME_COMMAND_DWORD0;

Members

DUMMYSTRUCTNAME

DUMMYSTRUCTNAME.OPC

Specifies the Opcode (OPC) of the command to be executed.

DUMMYSTRUCTNAME.FUSE

An NVME_FUSED_OPERATION_CODES value that specifies whether this command is part of a fused operation and if so, which command it is in the sequence.

In a fused operation, a complex command is created by fusing together two simpler commands.

DUMMYSTRUCTNAME.Reserved0

DUMMYSTRUCTNAME.PSDT

Specifies whether Physical Region Pages (PRPs) or Scatter Gather Lists (SGLs) are used for any data transfer associated with the command. PRPs are used for all Admin commands.

This field uses the following values:

Value	Definition
00b	PRPs are used for this transfer.
01b	SGLs are used for this transfer.
10b	SGLs are used for this transfer.
11b	Reserved

If there is metadata that is not interleaved with the logical block data, as specified in the Format NVM command, then the Metadata Pointer (MPTR) field in the NVME_COMMAND structure is used to point to the metadata. The definition of the MPTR field is dependent on the setting in this field.

DUMMYSTRUCTNAME.CID

Specifies a unique identifier for the command when combined with the Submission Queue identifier (SQID) in the command completion entry.

AsUlong

Requirements

Requirement	Value
Minimum supported client	Windows 10
Header	nvme.h