enum nvme_status_type - type encoding for NVMe return values, when represented
as an int.
enum nvme_status_type {
NVME_STATUS_TYPE_SHIFT ,
NVME_STATUS_TYPE_MASK ,
NVME_STATUS_TYPE_NVME ,
NVME_STATUS_TYPE_MI
};
- NVME_STATUS_TYPE_SHIFT
- shift value for status bits
- NVME_STATUS_TYPE_MASK
- mask value for status bits
- NVME_STATUS_TYPE_NVME
- NVMe command status value, typically from CDW3
- NVME_STATUS_TYPE_MI
- NVMe-MI header status
The nvme_* api returns an int, with negative values indicating an internal or
syscall error, zero signifying success, positive values representing the NVMe
status.
That latter case (the NVMe status) may represent status values from different
parts of the transport/controller/etc, and are at most 16 bits of data. So, we
use the most-significant 3 bits of the signed int to indicate which type of
status this is.