blockdevice

type BlockQueueStats struct {
	// AddRandom is the status of a disk entropy (1 is on, 0 is off).
	AddRandom uint64
	// Dax indicates whether the device supports Direct Access (DAX) (1 is on, 0 is off).
	DAX uint64
	// DiscardGranularity is the size of internal allocation of the device in bytes, 0 means device
	// does not support the discard functionality.
	DiscardGranularity uint64
	// DiscardMaxHWBytes is the hardware maximum number of bytes that can be discarded in a single operation,
	// 0 means device does not support the discard functionality.
	DiscardMaxHWBytes uint64
	// DiscardMaxBytes is the software maximum number of bytes that can be discarded in a single operation.
	DiscardMaxBytes uint64
	// HWSectorSize is the sector size of the device, in bytes.
	HWSectorSize uint64
	// IOPoll indicates if polling is enabled (1 is on, 0 is off).
	IOPoll uint64
	// IOPollDelay indicates how polling will be performed, -1 for classic polling, 0 for hybrid polling,
	// with greater than 0 the kernel will put process issuing IO to sleep for this amount of time in
	// microseconds before entering classic polling.
	IOPollDelay int64
	// IOTimeout is the request timeout in milliseconds.
	IOTimeout uint64
	// IOStats indicates if iostats accounting is used for the disk (1 is on, 0 is off).
	IOStats uint64
	// LogicalBlockSize is the logical block size of the device, in bytes.
	LogicalBlockSize uint64
	// MaxHWSectorsKB is the maximum number of kilobytes supported in a single data transfer.
	MaxHWSectorsKB uint64
	// MaxIntegritySegments is the max limit of integrity segments as set by block layer which a hardware controller
	// can handle.
	MaxIntegritySegments uint64
	// MaxSectorsKB is the maximum number of kilobytes that the block layer will allow for a filesystem request.
	MaxSectorsKB uint64
	// MaxSegments is the number of segments on the device.
	MaxSegments uint64
	// MaxSegmentsSize is the maximum segment size of the device.
	MaxSegmentSize uint64
	// MinimumIOSize is the smallest preferred IO size reported by the device.
	MinimumIOSize uint64
	// NoMerges shows the lookup logic involved with IO merging requests in the block layer. 0 all merges are
	// enabled, 1 only simple one hit merges are tried, 2 no merge algorithms will be tried.
	NoMerges uint64
	// NRRequests is the number of how many requests may be allocated in the block layer for read or write requests.
	NRRequests uint64
	// OptimalIOSize is the optimal IO size reported by the device.
	OptimalIOSize uint64
	// PhysicalBlockSize is the physical block size of device, in bytes.
	PhysicalBlockSize uint64
	// ReadAHeadKB is the maximum number of kilobytes to read-ahead for filesystems on this block device.
	ReadAHeadKB uint64
	// Rotational indicates if the device is of rotational type or non-rotational type.
	Rotational uint64
	// RQAffinity indicates affinity policy of device, if 1 the block layer will migrate request completions to the
	// cpu “group” that originally submitted the request, if 2 forces the completion to run on the requesting cpu.
	RQAffinity uint64
	// SchedulerList contains list of available schedulers for this block device.
	SchedulerList []string
	// SchedulerCurrent is the current scheduler for this block device.
	SchedulerCurrent string
	// WriteCache shows the type of cache for block device, "write back" or "write through".
	WriteCache string
	// WriteSameMaxBytes is the number of bytes the device can write in a single write-same command.
	// A value of ‘0’ means write-same is not supported by this device.
	WriteSameMaxBytes uint64
	// WBTLatUSec is the target minimum read latency, 0 means feature is disables.
	WBTLatUSec int64
	// ThrottleSampleTime is the time window that blk-throttle samples data, in millisecond. Optional
	// exists only if CONFIG_BLK_DEV_THROTTLING_LOW is enabled.
	ThrottleSampleTime *uint64
	// Zoned indicates if the device is a zoned block device and the zone model of the device if it is indeed zoned.
	// Possible values are: none, host-aware, host-managed for zoned block devices.
	Zoned string
	// NRZones indicates the total number of zones of the device, always zero for regular block devices.
	NRZones uint64
	// ChunksSectors for RAID is the size in 512B sectors of the RAID volume stripe segment,
	// for zoned host device is the size in 512B sectors.
	ChunkSectors uint64
	// FUA indicates whether the device supports Force Unit Access for write requests.
	FUA uint64
	// MaxDiscardSegments is the maximum number of DMA entries in a discard request.
	MaxDiscardSegments uint64
	// WriteZeroesMaxBytes the maximum number of bytes that can be zeroed at once.
	// The value 0 means that REQ_OP_WRITE_ZEROES is not supported.
	WriteZeroesMaxBytes uint64
}

type DeviceMapperInfo struct {
	// Name is the string containing mapped device name.
	Name string
	// RqBasedSeqIOMergeDeadline determines how long (in microseconds) a request that is a reasonable merge
	// candidate can be queued on the request queue.
	RqBasedSeqIOMergeDeadline uint64
	// Suspended indicates if the device is suspended (1 is on, 0 is off).
	Suspended uint64
	// UseBlkMQ indicates if the device is using the request-based blk-mq I/O path mode (1 is on, 0 is off).
	UseBlkMQ uint64
	// UUID is the DM-UUID string or empty string if DM-UUID is not set.
	UUID string
}

type Diskstats struct {
	Info
	IOStats
	// IoStatsCount contains the number of io stats read. For kernel versions 5.5+,
	// there should be 20 fields read. For kernel versions 4.18+,
	// there should be 18 fields read. For earlier kernel versions this
	// will be 14 because the discard values are not available.
	IoStatsCount int
}

type FS struct {
	// contains filtered or unexported fields
}

type IOStats struct {
	// ReadIOs is the number of reads completed successfully.
	ReadIOs uint64
	// ReadMerges is the number of reads merged.  Reads and writes
	// which are adjacent to each other may be merged for efficiency.
	ReadMerges uint64
	// ReadSectors is the total number of sectors read successfully.
	ReadSectors uint64
	// ReadTicks is the total number of milliseconds spent by all reads.
	ReadTicks uint64
	// WriteIOs is the total number of writes completed successfully.
	WriteIOs uint64
	// WriteMerges is the number of reads merged.
	WriteMerges uint64
	// WriteSectors is the total number of sectors written successfully.
	WriteSectors uint64
	// WriteTicks is the total number of milliseconds spent by all writes.
	WriteTicks uint64
	// IOsInProgress is number of I/Os currently in progress.
	IOsInProgress uint64
	// IOsTotalTicks is the number of milliseconds spent doing I/Os.
	// This field increases so long as IosInProgress is nonzero.
	IOsTotalTicks uint64
	// WeightedIOTicks is the weighted number of milliseconds spent doing I/Os.
	// This can also be used to estimate average queue wait time for requests.
	WeightedIOTicks uint64
	// DiscardIOs is the total number of discards completed successfully.
	DiscardIOs uint64
	// DiscardMerges is the number of discards merged.
	DiscardMerges uint64
	// DiscardSectors is the total number of sectors discarded successfully.
	DiscardSectors uint64
	// DiscardTicks is the total number of milliseconds spent by all discards.
	DiscardTicks uint64
	// FlushRequestsCompleted is the total number of flush request completed successfully.
	FlushRequestsCompleted uint64
	// TimeSpentFlushing is the total number of milliseconds spent flushing.
	TimeSpentFlushing uint64
}

type Info struct {
	MajorNumber uint32
	MinorNumber uint32
	DeviceName  string
}

type UnderlyingDeviceInfo struct {
	// DeviceNames is the list of devices names
	DeviceNames []string
}