// Copyright (C) 2022-2023  Luke Shumaker <lukeshu@lukeshu.com>
//
// SPDX-License-Identifier: GPL-2.0-or-later

package btrfsitem

import (
	"git.lukeshu.com/btrfs-progs-ng/lib/binstruct"
	"git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfsprim"
	"git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfsvol"
)

// A Dev describes a physical volume that is part of the filesystem.
//
// Key:
//
//	key.objectid = BTRFS_DEV_ITEMS_OBJECTID
//	key.offset   = device_id (starting at 1)
type Dev struct { // trivial DEV_ITEM=216
	DevID btrfsvol.DeviceID `bin:"off=0x0,    siz=0x8"`

	NumBytes     uint64 `bin:"off=0x8,    siz=0x8"`
	NumBytesUsed uint64 `bin:"off=0x10,   siz=0x8"`

	IOOptimalAlign uint32 `bin:"off=0x18,   siz=0x4"`
	IOOptimalWidth uint32 `bin:"off=0x1c,   siz=0x4"`
	IOMinSize      uint32 `bin:"off=0x20,   siz=0x4"` // sector size

	Type        uint64               `bin:"off=0x24,   siz=0x8"`
	Generation  btrfsprim.Generation `bin:"off=0x2c,   siz=0x8"`
	StartOffset uint64               `bin:"off=0x34,   siz=0x8"`
	DevGroup    uint32               `bin:"off=0x3c,   siz=0x4"`
	SeekSpeed   uint8                `bin:"off=0x40,   siz=0x1"`
	Bandwidth   uint8                `bin:"off=0x41,   siz=0x1"`

	DevUUID btrfsprim.UUID `bin:"off=0x42,   siz=0x10"`
	FSUUID  btrfsprim.UUID `bin:"off=0x52,   siz=0x10"`

	binstruct.End `bin:"off=0x62"`
}